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Two hypotheses have been proposed in order to account for velar softening, i.e., a process through which /k/ changes to an affricate. Whereas one hypothesis states that for the process to apply the velar stop has to be realized as an (alveolo) palatal stop (articulation-based hypothesis), the other claims that velar softening is triggered by acoustic similarity between the input and output segments (acoustic equivalence hypothesis). The present paper investigates the acoustic equivalence hypothesis by comparing several acoustic properties of /k/ in various vowel contexts with those of /ts , ts , tc / for three languages differing in stop burst aspiration, i.e., German, Polish and Catalan. Results suggest that the acoustic equivalence hypothesis could account for velar softening in aspirated velar stops but not in unaspirated velar stops. The results also provide an explanation as to why aspirated velar stops are prone to undergo softening more easily when followed by front vocalic segments than in other contexts and positions
In this paper it is argued that several typologically unrelated languages share the tendency to avoid voiced sibilant affricates. This tendency is explained by appealing to the phonetic properties of the sounds, and in particular to their aerodynamic characteristics. On the basis of experimental evidence it is shown that conflicting air pressure requirements for maintaining voicing and frication are responsible for the avoidance of voiced affricates. In particular, the air pressure released from the stop phase of the affricate is too high to maintain voicing which in consequence leads to a devoicing of the frication part.
In this paper it is argued that several typologically unrelated languages share the tendency to avoid voiced sibilant affricates. This tendency is explained by appealing to the phonetic properties of the sounds, and in particular to their aerodynamic characteristics. On the basis of experimental evidence it is shown that conflicting air pressure requirements for maintaining voicing and frication are responsible for the avoidance of voiced affricates. In particular, the air pressure released from the stop phase of the affricate is too high to maintain voicing which in consequence leads to a devoicing of the frication part.
A high-precision pressure probe is described which allows non-invasive online-monitoring of the water relations of intact leaves. Real-time recording of the leaf water status occurred by data transfer to an Internet server. The leaf patch clamp pressure probe measures the attenuated pressure, Pp, of a leaf patch in response to a constant clamp pressure, Pclamp. Pp is sensed by a miniaturized silicone pressure sensor integrated into the device. The magnitude of Pp is dictated by the transfer function of the leaf, Tf, which is a function of leaf patch volume and ultimately of cell turgor pressure, Pc, as shown theoretically. The power function Tf=f(Pc) theoretically derived was experimentally confirmed by concomitant Pp and Pc measurements on intact leaflets of the liana Tetrastigma voinierianum under greenhouse conditions. Simultaneous Pp recordings on leaflets up to 10 m height above ground demonstrated that changes in Tf induced by Pc changes due to changes of microclimate and/or of the irrigation regime were sensitively reflected in corresponding changes of Pp. Analysis of the data show that transpirational water loss during the morning hours was associated with a transient rise in turgor pressure gradients within the leaflets. Subsequent recovery of turgescence during the afternoon was much faster than the preceding transpiration-induced water loss if the plants were well irrigated. Our data show the enormous potential of the leaf patch clamp pressure probe for leaf water studies including unravelling of the hydraulic communication between neighbouring leaves and over long distances within tall plants (trees).
Poster presentation A central problem in neuroscience is to bridge local synaptic plasticity and the global behavior of a system. It has been shown that Hebbian learning of connections in a feedforward network performs PCA on its inputs [1]. In recurrent Hopfield network with binary units, the Hebbian-learnt patterns form the attractors of the network [2]. Starting from a random recurrent network, Hebbian learning reduces system complexity from chaotic to fixed point [3]. In this paper, we investigate the effect of Hebbian plasticity on the attractors of a continuous dynamical system. In a Hopfield network with binary units, it can be shown that Hebbian learning of an attractor stabilizes it with deepened energy landscape and larger basin of attraction. We are interested in how these properties carry over to continuous dynamical systems. Consider system of the form Math(1) where xi is a real variable, and fi a nondecreasing nonlinear function with range [-1,1]. T is the synaptic matrix, which is assumed to have been learned from orthogonal binary ({1,-1}) patterns ξμ, by the Hebbian rule: Math. Similar to the continuous Hopfield network [4], ξμ are no longer attractors, unless the gains gi are big. Assume that the system settles down to an attractor X*, and undergoes Hebbian plasticity: T´ = T + εX*X*T, where ε > 0 is the learning rate. We study how the attractor dynamics change following this plasticity. We show that, in system (1) under certain general conditions, Hebbian plasticity makes the attractor move towards its corner of the hypercube. Linear stability analysis around the attractor shows that the maximum eigenvalue becomes more negative with learning, indicating a deeper landscape. This in a way improves the system´s ability to retrieve the corresponding stored binary pattern, although the attractor itself is no longer stabilized the way it does in binary Hopfield networks.
The lysosomal ABC transporter associated with antigen processing-like (TAPL, ABCB9) acts as an ATP-dependent polypeptide transporter with broad length selectivity. To characterize in detail its substrate specificity, a procedure for functional reconstitution of human TAPL was developed. By intensive screening of detergents, ideal solubilization conditions were evolved with respect to efficiency, long term stability, and functionality of TAPL. TAPL was isolated in a two-step procedure with high purity and, subsequently, reconstituted into proteoliposomes. The peptide transport activity of reconstituted TAPL strongly depends on the lipid composition. With the help of combinatorial peptide libraries, the key positions of the peptides were localized to the N- and C-terminal residues with respect to peptide transport. At both ends, TAPL favors positively charged, aromatic, or hydrophobic residues and disfavors negatively charged residues as well as asparagine and methionine. Besides specific interactions of both terminal residues, electrostatic interactions are important, since peptides with positive net charge are more efficiently transported than negatively charged ones.
Assessment of ecologically relevant hydrological change in China due to water use and reservoirs
(2008)
As China’s economy booms, increasing water use has significantly affected hydro-geomorphic processes and thus the ecology of surface waters. A large variety of hydrological changes arising from human activities such as reservoir construction and management, water abstraction, water diversion and agricultural land expansion have been sustained throughout China. Using the global scale hydrological and water use model WaterGAP, natural and anthropogenically altered flow conditions are calculated, taking into account flow alterations due to human water consumption and 580 large reservoirs. The impacts resulting from water consumption and reservoirs have been analyzed separately. A modified “Indicators of Hydrologic Alteration” approach is used to describe the human pressures on aquatic ecosystems due to anthropogenic alterations in river flow regimes. The changes in long-term average river discharge, average monthly mean discharge and coefficients of variation of monthly river discharges under natural and impacted conditions are compared and analyzed. The indicators show very significant alterations of natural river flow regimes in a large part of northern China and only minor alterations in most of southern China. The detected large alterations in long-term average river discharge, the seasonality of flows and the inter-annual variability in the northern half of China are very likely to have caused significant ecological impacts.
Our study is concerned with the identification of ‘difficult’ structure s in the acquisition of a foreign language, which will shed light on theoretical considerations of L2 processing. We argue that – compared to simple vocabulary items or abstract syntactic patterns – structures that contain lexical material as well as categorial variables are especially difficult to acquire. The difficulty level for particular patterns is shown to depend on surface invariability but not on the syntactic categories within which target patterns are embedded. As an example we study the distribution of certain structures which are underused by L2 German learners.
Lichens are the object of investigation within the framework of the BIOTA Southern Africa project, subproject S04 (http://www.biota-africa.org). This interdisciplinary research project, installed in 2000, focuses on the analysis of biodiversity and its changes along climatic and vegetation gradients (transects) in Namibia and in the Republic of South Africa. In the context of this project, studies on the diversity of lichens are carriedout. Special reference is given to the monitoring of lichens growing on soil, which form the so called biological soil crusts.Lichen diversity is assessed and analysed with respect to its spatial and temporal changes. These are related to various abioticand biotic factors such as climate, soil features and land use. The indicator value of certain terricolouslichen taxaand/or lichen groups (communities) is investigated for the study area, and it is intended to use itin a future long-term monitoring programme in the region. In this brochure, we whish to explain what lichens are, how do they live and where do they grow, and why they are so important as bioindicatorsin arid and semi-arid areas of the world. The activities of the S04 subproject along the BIOTA transect are described, as well as the methods used for monitoring environmental changes in Southern Africa using soil-inhabiting lichens.
A preliminary checklist of Calpini is provided, incorporating corrections and changes to publication dates and nomenclature as presented in the checklists of Poole (1989), Fibiger and Lafontaine (2005), and Holloway (2005). Culasta Moore is removed from synonymy with Calyptra Ochsenheimer. Eudocima talboti (Prout) and Graphigona antica Walker are placed in synonymy with E. cajeta (Cramer) and G. regina (Guenée), respectively. Africalpe Krüger, Ferenta Walker, Gonodonta Hübner, Graphigona Walker, Oraesia Guenée, and Tetrisia Walker, are added to the tribe based on shared characters. The genera Cecharismena Möschler, Goniapteryx Perty, Pharga Walker, Phyprosopus Grote, Psammathodoxa Dyar, and Radara Walker are removed and considered incertae sedis. Hemiceratoides and Phyllodes are not considered to be members of Calpini.
In the title compound, C13H10N2O2, a Schiff base derivative, the dihedral angle between the two aromatic rings is 31.58 (3)°. The C=N double bond is essentially coplanar with the nitrophenyl ring. The torsion angle of the imine double bond is 175.97 (13)°, indicating that the C=N double bond is in a trans configuration. The crystal structure is stabilized by C-H...O contacts and [pi]-[pi] interactions (centroid-centroid distances of 3.807 and 3.808 Å). Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.002 Å; R factor = 0.034; wR factor = 0.093; data-to-parameter ratio = 10.3.
A small-world network has been suggested to be an efficient solution for achieving both modular and global processing-a property highly desirable for brain computations. Here, we investigated functional networks of cortical neurons using correlation analysis to identify functional connectivity. To reconstruct the interaction network, we applied the Ising model based on the principle of maximum entropy. This allowed us to assess the interactions by measuring pairwise correlations and to assess the strength of coupling from the degree of synchrony. Visual responses were recorded in visual cortex of anesthetized cats, simultaneously from up to 24 neurons. First, pairwise correlations captured most of the patterns in the population´s activity and, therefore, provided a reliable basis for the reconstruction of the interaction networks. Second, and most importantly, the resulting networks had small-world properties; the average path lengths were as short as in simulated random networks, but the clustering coefficients were larger. Neurons differed considerably with respect to the number and strength of interactions, suggesting the existence of "hubs" in the network. Notably, there was no evidence for scale-free properties. These results suggest that cortical networks are optimized for the coexistence of local and global computations: feature detection and feature integration or binding.
Transparent free relatives (TFRs) are constituents involving a WH-gap dependency in which the phrase that is predicated of the gap associated with 'what', not the wh-phrase itself, functions as the syntactic and semantic "nucleus." Previous analyses have either treated TFRs as a construction radically different from ordinary FRs, utilizing such mechanisms as parenthetical placement or grafts, or assimilated them to ordinary FRs, relying on abstract/empty head elements and a vague semantic relation holding between the gap and the predicate phrase. In this paper, we investigate how the puzzling properties of English TFRs can be accounted for in HPSG. The paper shows that the transparency effect of TRFs can be handled by feature inheritance from the nucleus predicate phrase, together with a constructional constraint that deals with the exocentric property of TFRs.
This paper analyzes liquidity in an order driven market. We only investigate the best limits in the limit order book, but also take into account the book behind these inside prices. When subsequent prices are close to the best ones and depth at them is substantial, larger orders can be executed without an extensive price impact and without deterring liquidity. We develop and estimate several econometric models, based on depth and prices in the book, as well as on the slopes of the limit order book. The dynamics of different dimensions of liquidity are analyzed: prices, depth at and beyond the best prices, as well as resiliency, i.e. how fast the different liquidity measures recover after a liquidity shock. Our results show a somewhat less favorable image of liquidity than often found in the literature. After a liquidity shock (in the spread or depth or in the book beyond the best limits), several dimension of liquidity deteriorate at the same time. Not only does the inside spread increase, and depth at the best prices decrease, also the difference between subsequent bid and ask prices may become larger and depth provided at them decreases. The impacts are both econometrically and economically significant. Also, our findings point to an interaction between different measures of liquidity, between liquidity at the best prices and beyond in the book, and between ask and bid side of the market.
Conclusion Scale Integration Based on the results of spike-field coherence, the underlying process of shortterm memory seems to involve networks of different sizes within and, most probably, beyond prefrontal cortex. Spikes, which were generated by single neurons, cooperate with local field potentials, which were the slower fluctuations of the environment. Although differences among behavioral conditions appear to be based on rather few instances of phase-locked spikes, the task-related effects on spike-field coherence are highly reliable and cannot be explained by chance, as the comparison of results from experimental and simulated data shows. The differential locking of prefrontal neuron populations with two different frequency bands in their input signals suggests that neuronal activity underlying short-term memory in prefrontal cortex transiently engages cortical circuits on different spatial scales, probably in order to coordinate distributed processes. NeuroXidence method and Synchronizedfiring Based on the results of the calibration datasets, for bi- and multi-variate cases, the extension of NeuroXidence remains its sensitivity and reliability of detecting coordinate firing events for different processes. Based on this extension of NeuroXidence, we demonstrated that in monkey’s prefrontal cortex during short-term memory task, encoding and maintenance of the information rely on the formation of neuronal assemblies characterized by precise and reliable synchronization of spiking activity on a millisecond time scale, which is consistent with the results from spike-spike coherence. The task and performance dependent modulation of synchrony reflects the dynamic formation of group of neurons has large effect on short-term-memory.
In the eastern United States, the genus Cotinis Burmeister previously contained only C. nitida (L.), the common economic pest known as the "Green June Beetle". A new species from the Florida Keys, Cotinis aliena, is here described and illustrated. A checklist is provided for the genus, which includes 27 valid New World species, and 44 synonyms.
The dissertation deals with the general problem of how the brain can establish correspondences between neural patterns stored in different cortical areas. Although an important capability in many cognitive areas like language understanding, abstract reasoning, or motor control, this thesis concentrates on invariant object recognition as application of correspondence finding. One part of the work presents a correspondence-based, neurally plausible system for face recognition. Other parts address the question of visual information routing over several stages by proposing optimal architectures for such routing ('switchyards') and deriving ontogenetic mechanisms for the growth of switchyards. Finally, the idea of multi-stage routing is united with the object recognition system introduced before, making suggestions of how the so far distinct feature-based and correspondence-based approaches to object recognition could be reconciled.
We disassembled monomeric and dimeric yeast ATP synthase under mild conditions to identify labile proteins and transiently stable subcomplexes that had not been observed before. Specific removal of subunits α, β, oligomycin sensitivity conferring protein (OSCP), and h disrupted the ATP synthase at the γ-α3β3 rotor-stator interface. Loss of two F1-parts from dimeric ATP synthase led to the isolation of a dimeric subcomplex containing membrane and peripheral stalk proteins thus identifying the membrane/peripheral stalk sectors immediately as the dimerizing parts of ATP synthase. Almost all subunit a was found associated with a ring of 10 c-subunits in two-dimensional blue native/SDS gels. We therefore postulate that c10a1-complex is a stable structure in resting ATP synthase until the entry of protons induces a breaking of interactions and stepwise rotation of the c-ring relative to the a-subunit in the catalytic mechanism. Dimeric subunit a was identified in SDS gels in association with two c10-rings suggesting that a c10a2c10-complex may constitute an important part of the monomer-monomer interface in dimeric ATP synthase that seems to be further tightened by subunits b, i, e, g, and h. In contrast to the monomer-monomer interface, the interface between dimers in higher oligomeric structures remains largely unknown. However, we could show that the natural inhibitor protein Inh1 is not required for oligomerization.
Varicella zoster virus (VZV) belongs to one of the eight herpes viruses known to infect humans. While primary VZV infection (chickenpox) is generally a disease of childhood, herpes zoster occurs primarily in elderly persons (>50 years). Herpes zoster, also called shingles, is a neurocutaneous disease resulting from reactivation of latent VZV infection within dorsal root ganglia. Severe complications may occur in elderly persons and immunocompromised of any age, including severe complication of the eye, ear, skin and internal organs, and the peripheral and central nervous systems. A progressive decline of VZV-specific cell-mediated immunity and age are associated with an increased incidence and severity of herpes zoster and postherpetic neuralgia (PHN). PHN is the most common complication of herpes zoster causing chronic, debilitating pain. In cases with characteristic signs and symptoms (presence of prodromal pain, eruptions, grouped vesicles, segmental pain), the diagnosis is almost distinctive enough and no laboratory investigations are required. However, for patients lacking no characteristic pathology, a rapid laboratory diagnosis may be helpful to begin antiviral therapy as soon as possible. Antiviral therapy should be initiated immediately within 72 h after rash onset, particularly in older patients. The main aim of treatment is to control and reduce acute zoster pain, shorten virus replication, avoid dissemination of skin lesions and prevent PHN and other severe complications. The aim of the present review is to outline advantages and disadvantages of different herpes zoster laboratory methods (microscopy, direct immunofluorescence assay, detection of viral DNA, virus isolation and serological methods). A live attenuated VZV vaccine has been developed to prevent herpes zoster and PHN in individuals >60 years of age (Shingles Prevention Study). This review summarises the epidemiology, pathogenesis, clinical aspects, complications, therapy and prevention of varicella zoster.
Samples of freshly fallen snow were collected at the high alpine research station Jungfraujoch (Switzerland) in February and March 2006 and 2007, during the Cloud and Aerosol Characterization Experiments (CLACE) 5 and 6. In this study a new technique has been developed and demonstrated for the measurement of organic acids in fresh snow. The melted snow samples were subjected to solid phase extraction and resulting solution analysed for organic acids by HPLC-MS-TOF using negative electrospray ionization. A series of linear dicarboxylic acids from C5 to C13 and phthalic acid, were identified and quantified. In several samples the biogenic acid pinonic acid was also observed. In fresh snow the median concentration of the most abundant acid, adipic acid, was 0.69 µg L−1 in 2006 and 0.70 µg L−1 in 2007. Glutaric acid was the second most abundant dicarboxylic acid found with median values of 0.46 µg L−1 in 2006 and 0.61 µg L−1 in 2007, while the aromatic acid phthalic acid showed a median concentration of 0.34 µg L−1 in 2006 and 0.45 µg L−1 in 2007. The concentrations in the samples from various snowfall events varied significantly, and were found to be dependent on the back trajectory of the air mass arriving at Jungfraujoch. Air masses of marine origin showed the lowest concentrations of acids whereas the highest concentrations were measured when the air mass was strongly influenced by boundary layer air.
Twentieth-century scholars have thought little about the attractions of Descartes’ thinking. Especially in feminist theory, he has a bad press as the ‘instigator’ of the body-mind-split – seen as one of the theoretical bases for the subordination of women in Western culture. Seen from within seventeenth-century discourse it is the dictum that can be inferred from his writings that ‘the mind has no sex’ and which can be seen as an appeal to think about rational capacities in the utopian perspective of a gender neutral discourse. My work analyses this “face” of Cartesianism as it was adapted in favour of English seventeenth-century women. How were the specific tenets of Descartes’ philosophy employed on behalf of English women in the second half of the seventeenth century in England? My focus is on Descartes as a thinker, who – whatever his real or imagined intention might have been – provided women in seventeenth-century England with tools with which to change their status, in other words: with instruments of empowerment. So why were Descartes’ arguments so attractive for women? Descartes had argued for equal rational abilities among individuals in a gender neutral way. He had further critiqued generally accepted truth with his universal doubt. I believe this specific combination of ideas, affirming their rational capabilities, was seen by a number of women as an invitation to become involved in spheres of activity from which they were previously excluded. Moreover, a specific set of Descartes’ arguments provided a number of English women with a strategy to extend female agency. Not only did Descartes’ views legitimate female rationality, they also allowed an acknowledgement that this female intellect was equally connected to “truth” as that of their male contemporaries. As a consequence, women developed an increased self-esteem and inspiration to pursue their own independent study (and in some cases publishing). These ideas eventually helped to bring forward a demand for female education, as girls and women were still excluded from formal education in seventeenth-century England. My general thesis is that Cartesianism, as one of the earliest universalist theories on the nature of human reason, introduced new possibilities into the English debate over the nature and, hence, social position of women. It brought a radical twist to the already existing discussion on women by offering new critical tools which were taken up to argue on behalf of English women. In my work I examine the specific historical conditions of the reception of Descartes’ thought in England, the philosophical appeal of his ideas for women and analyse the writings of two English ‘disciples’ of Descartes: Margaret Cavendish, Duchess of Newcastle and Mary Astell.
This paper introduces adaptive learning and endogenous indexation in the New-Keynesian Phillips curve and studies disinflation under inflation targeting policies. The analysis is motivated by the disinflation performance of many inflation-targeting countries, in particular the gradual Chilean disinflation with temporary annual targets. At the start of the disinflation episode price-setting firms’ expect inflation to be highly persistent and opt for backward-looking indexation. As the central bank acts to bring inflation under control, price-setting firms revise their estimates of the degree of persistence. Such adaptive learning lowers the cost of disinflation. This reduction can be exploited by a gradual approach to disinflation. Firms that choose the rate for indexation also re-assess the likelihood that announced inflation targets determine steady-state inflation and adjust indexation of contracts accordingly. A strategy of announcing and pursuing short-term targets for inflation is found to influence the likelihood that firms switch from backward-looking indexation to the central bank’s targets. As firms abandon backward-looking indexation the costs of disinflation decline further. We show that an inflation targeting strategy that employs temporary targets can benefit from lower disinflation costs due to the reduction in backward-looking indexation.
ALICE (A Large Ion Collider Experiment), is the dedicated heavy-ion experiment at the Large Hadron Collider (LHC) at CERN. It is optimised to reconstruct and identify the particles created in a lead-lead collision with a centre of mass energy of 5.5TeV. The main tracking detector is a large-volume time-projection chamber (TPC). With an active volume of about 88m^3 and a total readout area of 32.5m^2 it is the most challenging TPC ever build. A central electrode divides the 5m long detector into two drift regions. Each readout side is subdivided into 18 inner and 18 outer multi-wire proportional read-out chambers. The readout area is subdivide into 557568 pads, where each pad is read out by and electronics chanin. A complex calibration is needed in order to reach the design position-resolution of the reconstructed particle tracks of about 200um. One part of the calibration lies in understanding the electronic-response. The work at hand presents results of the pedestal and noise behaviour of the front-end electronics (FEE), measurements of the pulse-shaping properties of the FEE using results obtained with a calibration pulser and measurements performed with the laser-calibration system. The data concerned were taken during two phases of the TPC commissioning. First measurements were performed in the clean room where the TPC was built. After the TPC was moved underground and built into the experiment, a second round of commissioning took place. Noise measurements in the clean room revealed a very large fraction of pads with noise values larger than the design specifications. The unexpected high noise values could be explained by the 'ground bounce' effect. Two modifications helped to reduce this effect: A desynchronisation in the the start of the readout of groups of channels and a modification in the grounding scheme of the FEE. Further noise measurements were carried out after the TPC has been moved to the experimental area underground. Here even a larger fraction of channels showed too large noise values. This could be traced back to a common mode current injected by the electronics power supplies. To study the shaping properties of the FEE a calibration pulser was used. To generate signals in the FEE a pulse is injected to the cathode wires of the read-out chambers. Due to manufacturing tolerances slight channel-by-channel variations of the shaping properties are expected. This effects the determination of the arrival time as well as the measured integral signal of the induced charge and has to be corrected. The measured arrival time variations follow a Gaussian distribution with a width (sigma) of 6.2ns. This corresponds to an error of the cluster position of about 170um. The charge variations are on the level of 2.8%. In order to reach the intrinsic resolution on the measurement of the specific energy loss of the particles (6%) those variations have to be taken into account. The photons of the laser-calibration system are energetic enough to emit photo electrons off metallic surfaces. Most interesting for the detector calibration are photo electrons from the central electrode. The laser light is intense enough to get a signal in all readout channels of the TPC. Since the central electrode is a smooth surface, differences in the arrival time between sectors reveal mechanical displacements of the readout sectors and can be used to correct for this effect. In addition the measurements can be used to determine the electron drift velocity in the TPC gas. The drift velocity measurements have shown a vertical as well as a radial gradient. The first can be explained by the temperature gradient, which naturally builds up in the 5m high detector. The second gradient is most probably caused by a relative conical deformation of the readout plane and the central electrode.
The purpose of this study was to reconstruct the depositional environment, the genesis and the composition of Miocene coals in the Kutai Basin, East Kalimantan, Indonesia and to improve our understanding of the factors controlling the organic and inorganic composition, variation of biomarkers, and the peat forming vegetation of the coals. To achieve the aim methods belonging to three different disciplines were applied: 1. Coal petrology (chapter 3) 2. Inorganic geochemistry: sulfur, pyrite and mineral matter distributions (chapter 4) 3. Organic geochemistry of saturated, aromatic hydrocarbon fractions and stable carbon isotopic composition (chapter 5 and 6) Coal petrology Coal developes from peat deposited in mires, mainly in swamps and raised bogs. It is therefore necessary to consider how peat was formed in the past. Coal contains a variety of plant tissues in different degrees of preservation. Tissues of distinct origin are microscopically identifiable and can frequently be related to certain parts of the plant, such as cuticles, woody structures, spores, algal, resin, etc. Together with the particles of less certain origin they are termed macerals which are the petrographic components of coal. During and after deposition of plant remains in sedimentary basins, the organic matter will undergo a sequence of physical, biochemical and chemical changes, which finally results in the formation of coals of increasing rank depending mainly on the temperature influence. The process of coalification begins with practically unaltered plant material and peat, and continues with increasing rank through brown coal, bituminous coal, and finally to anthracite as well as graphite. Coal petrography provides valuable of data of maceral and mineral percentages with reflectance values, which can be used to reconstruct the depositional environment and the coalification processes. In lower rank coals, the material is represented by a group of macerals called huminite, and in bituminous and anthracite coals by a group of macerals called vitrinite. Coal petrography analyses have been carried out on samples from some Miocene coal seams from Kutai Basin. The study has shown that huminite reflectance values of coal samples from ...
Introduction: Healthcare workers (HCWs) are exposed to bloodborne pathogens (e.g., contaminated devices). In the healthcare environment, needlestick injuries (NSI) represent a major risk factor in the transmission of hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV). Medical students are at risk of occupational exposure to bloodborne viruses following needlestick injuries during medical education. Reporting of needlestick injuries is an important step for initiating early prophylaxis or treatment. In the case of a bloodborne infection, pursuant to insure law could result in a claim. The objective of the present study was to describe occupational blood exposure of medical students through needlestick injuries.
Methods: Sixth-year medical students were invited to complete an anonymous questionnaire.
Results: In our study, 58.8% (n=183/311) of medical students recalled at least one needlestick injury during their studies. Overall, 284 needlestick injuries were reported. Only 38.3% of medical students reported all NSI to the appropriate hospital personnel. The main reason (54.0%) for not reporting NSI was being ashamed of having an NSI.
Conclusions: Occupational exposure to blood is a common problem among medical students. Efforts are required to ensure greater awareness among medical students about the risk of bloodborne pathogens. Proper training in procedures and how to act in case of injury should be offered to reduce the number of needlestick injuries.
Background Medical students come into contact with infectious diseases early on their career. Immunity against vaccine-preventable diseases is therefore vital for both medical students and the patients with whom they come into contact. Methods The purpose of this study was to compare the medical history and serological status of selected vaccine-preventable diseases of medical students in Germany. Results The overall correlation between medical history statements and serological findings among the 150 students studied was 86.7 %, 66.7 %, 78 % and 93.3 % for measles, mumps, rubella and varicella, conditional on sufficient immunity being achieved after one vaccination. Conclusions Although 81.2 % of the students medical history data correlated with serological findings, significant gaps in immunity were found. Our findings indicate that medical history alone is not a reliable screening tool for immunity against the vaccine-preventable diseases studied.
The timing of feedback to early visual cortex in the perception of long-range apparent motion
(2008)
When 2 visual stimuli are presented one after another in different locations, they are often perceived as one, but moving object. Feedback from area human motion complex hMT/V5+ to V1 has been hypothesized to play an important role in this illusory perception of motion. We measured event-related responses to illusory motion stimuli of varying apparent motion (AM) content and retinal location using Electroencephalography. Detectable cortical stimulus processing started around 60-ms poststimulus in area V1. This component was insensitive to AM content and sequential stimulus presentation. Sensitivity to AM content was observed starting around 90 ms post the second stimulus of a sequence and most likely originated in area hMT/V5+. This AM sensitive response was insensitive to retinal stimulus position. The stimulus sequence related response started to be sensitive to retinal stimulus position at a longer latency of 110 ms. We interpret our findings as evidence for feedback from area hMT/V5+ or a related motion processing area to early visual cortices (V1, V2, V3).
„Great writers,“ those who constitute our canon (at any given moment, one should add warily, since aesthetic canons fluctuate considerably over time), have invariably been the focus of reception studies, partly because they provide the most fertile ground for research, but partly also because literary scholars (and in particular the aspiring doctoral candidate: I myself graduated with an influence /reception study of this kind) need some justification for their endeavors, and what better ticket into the ivory rower - or onto the book market - than the study of the most seminal and widely accepted authors? James Joyce is just such a „great author.“ And „James Joyce and German Literature,“ the subject of this essay, must inevitably result in some form of reception study. But just what form should it take? Within the limited space of one article, it would be impossible to survey in toto Joyce's influence on German literature; that is, the multiple receptions of Joyce by some four or five generations of authors writing in German.
Poster presentation: Purpose of the study To compare the lipometabolic profiles of three double-boosted protease inhibitor (PI) regimens at standard dose, containing saquinavir and ritonavir in combination with lopinavir (LOPSAQ), atazanavir (ATSAQ) or fosamprenavir (FOSAQ) in HIV-positive patients, treated without reverse transcriptase inhibitors (RTI). ...
Background The inhibitor telaprevir (VX-950) of the hepatitis C virus (HCV) protease NS3-4A has been tested in a recent phase 1b clinical trial in patients infected with HCV genotype 1. This trial revealed residue mutations that confer varying degrees of drug resistance. In particular, two protease positions with the mutations V36A/G/L/M and T54A/S were associated with low to medium levels of drug resistance during viral breakthrough, together with only an intermediate reduction of viral replication fitness. These mutations are located in the protein interior and far away from the ligand binding pocket. Results Based on the available experimental structures of NS3-4A, we analyze the binding mode of different ligands. We also investigate the binding mode of VX-950 by protein-ligand docking. A network of non-covalent interactions between amino acids of the protease structure and the interacting ligands is analyzed to discover possible mechanisms of drug resistance. We describe the potential impact of V36 and T54 mutants on the side chain and backbone conformations and on the non-covalent residue interactions. We propose possible explanations for their effects on the antiviral efficacy of drugs and viral fitness. Molecular dynamics simulations of T54A/S mutants and rotamer analysis of V36A/G/L/M side chains support our interpretations. Experimental data using an HCV V36G replicon assay corroborate our findings. Conclusion T54 mutants are expected to interfere with the catalytic triad and with the ligand binding site of the protease. Thus, the T54 mutants are assumed to affect the viral replication efficacy to a larger degree than V36 mutants. Mutations at V36 and/or T54 result in impaired interaction of the protease residues with the VX-950 cyclopropyl group, which explains the development of viral breakthrough variants.
his study aims at a detailed characterization of an ultra-fine aerosol particle counting system for operation on board the Russian high altitude research aircraft M-55 "Geophysica" (maximum ceiling of 21 km). The COndensation PArticle counting Systems (COPAS) consists of an aerosol inlet and two dual-channel continuous flow Condensation Particle Counters (CPCs).
The aerosol inlet, adapted for COPAS measurements on board the M-55 "Geophysica", is described concerning aspiration, transmission, and transport losses. The counting efficiencies of the CPCs using the chlorofluorocarbon FC-43 as the working fluid are studied experimentally at two pressure conditions, 300 hPa and 70 hPa. Three COPAS channels are operated with different temperature differences between the saturator and the condenser block yielding smallest detectable particle sizes (dp50 – as 50% detection "cut off" diameters) of 6 nm, 11 nm, and 15 nm, respectively, at ambient pressure of 70 hPa. The fourth COPAS channel is operated with an aerosol heating line (250°C) for a determination of the non-volatile number of particles. The heating line is experimentally proven to volatilize pure H2SO4-H2O particles for a particle diameter (dp) range of 11 nm<dp<200 nm.
Additionally this study includes investigation to exclude auto-nucleation of the working fluid inside the CPCs. An instrumental inter-comparison (cross-correlation) has been performed for several measurement flights and mission flights in the Arctic and the Tropics are discussed. Finally, COPAS measurements are used for an aircraft plume crossing analysis.
P-type ATPases are membrane proteins acting as ion pumps that drive an active transport of cations across the membrane against a concentration gradient. The required energy for the ion transport is provided by binding and hydrolysis of ATP. A reaction mechanism of ion transport and energy transduction is assumed to be common for all P-type ATPases and generally described by the Post-Albers cycle. Transient currents and charge translocation of P-type ATPases were extensively investigated by electrical measurements that apply voltage jumps to initiate the reaction cycle. In this study, we simulate an applied voltage across the membrane by an electric field and perform electrostatic calculations in order to verify the experimentally-driven hypothesis that the energy transduction mechanism is regulated by specific structural elements. Side chain conformational and ionization changes induced by the electric field are evaluated for each transmembrane helix and the selectivity in response is qualitatively analyzed for the Ca2+-ATPase as well as for structural models of the Na+/K+-ATPase. Helix M5 responds with more conformer changes as compared to the other transmembrane helices what is even more emphasized when the stalk region is included. Thus our simulations support experimental results and indicate a crucial role for the highly conserved transmembrane helix M5 in the energy transduction mechanism of P-type ATPases.
New histone deacetylase inhibitors as potential therapeutic tools for advanced prostate carcinoma
(2008)
The anti-epileptic drug valproic acid is also under trial as an anti-cancer agent due to its histone deacetylase (HDAC) inhibitory properties. However, the effects of valproic acid (VPA) are limited and concentrations required for exerting anti-neoplastic effects in vitro may not be reached in tumour patients. In this study, we tested in vitro and in vivo effects of two VPA-derivatives (ACS2, ACS33) on pre-clinical prostate cancer models. PC3 and DU-145 prostate tumour cell lines were treated with various concentrations of ACS2 or ACS33 to perform in vitro cell proliferation 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and to evaluate tumour cell adhesion to endothelial cell monolayers. Analysis of acetylated histones H3 and H4 protein expression was performed by western blotting. In vivo tumour growth was conducted in subcutaneous xenograft mouse models. Tumour sections were assessed by immunohistochemistry for histone H3 acetylation and proliferation. ACS2 and ACS33 significantly up-regulated histone H3 and H4 acetylation in prostate cancer cell lines. In micromolar concentrations both compounds exerted growth arrest in PC3 and DU-145 cells and prevented tumour cell attachment to endothelium. In vivo, ACS33 inhibited the growth of PC3 in subcutaneous xenografts. Immunohistochemistry and western blotting confirmed increased histone H3 acetylation and reduced proliferation. ACS2 and ACS33 represent novel VPA derivatives with superior anti-tumoural activities, compared to the mother compound. This investigation lends support to the clinical testing of ACS2 or ACS33 for the treatment of prostate cancer.
Dualist Syntax
(2008)
A dualist syntax has two components: (1) the lexicon, a structured set of formatives ('words'); and (2) rules for combining those formatives into utterances. This paper defends syntactic dualism against three 'monist' challenges. First, evidence for lexical argument structure can be found in deverbal nominalization, which preserves that structure systematically. Second, words represent the smallest units for idiom formation and contextual polysemy effects, which is expected on the dualist view but not if word meanings are composed in the syntax. Third, the count/mass properties of nouns suggest an interleaving of conceptual and grammatical information in semantic composition.
Cytochrome P450 epoxygenases of the 2C family (CYP2C) are highly expressed in the endothelium and metabolize arachidonic acid to different regioisomers of epoxyeicosatrienoic acids (EET). They have a number of roles in the regulation of vascular tone and homeostasis by activating different signal transduction pathways and have recently been reported to be involved in proliferation and angiogenesis. However, the exact mechanisms by which epoxygenases regulate angiogenesis are still unclear. Therefore, the initial aim of the present study was to characterize the relevance of major signalling molecules that are involved in angiogenesis and to investigate possible signalling pathways involved. Initially the effect of CYP2C9 overexpression on expression levels of EphB4, a tyrosine kinase that plays a role in a number of developmental processes, was investigated. EphB4 protein expression was increased in CYP2C9 overexpressing cells without any effects on expression levels of its ligand ephrinB2. To clarify whether EphB4 is a critical determinant of CYP2C9-induced angiogenesis, endothelial cell sprouting was assessed using a collagen gel-based in vitro angiogenesis assay. Following transfection with EphB4 antisense or scrambled oligonucleotides, capillary-like structures were clearly present after 24 hours in cells overexpressing CYP2C9, while EphB4 downregulation abolished CYP2C9-induced sprouting. In addition stimulation of human umbilical vein endothelial cells with VEGF resulted in an increase in CYP2C expression and a subsequent increase of 11,12-EET production; an effect that was abolished by the CYP epoxygenases inhibitor MSPPOH as well as when cells were infected with a dominant negative mutant of AMPK. In vivo 11,12-EET treatment increased EphB4 expression in mesenteric arteries as well as in Matrigel plugs; an effect that was abolished when plugs were impregnated at the same time with small interfering RNA (siRNA) for EphB4. Furthermore, impregnation of Matrigel plugs with VEGF resulted in endothelial cell and smooth muscle cell recruitment into a Matrigel plug and this effect was mediated by CYP2C9-derived EETs as it was prevented by 14,15-EEZE. When infiltration of EET impregnated plugs with endothelial cells and pericytes/smooth muscle cells in vivo was compared to the effects seen in VEGF treated plugs, it was apparent that only EET treatment resulted in the formation of tube like structures that were covered by smooth muscle cells. Therefore, the final aim of the study was to further define the consequences of EET signalling in vivo as well as to characterize its physiological relevance. This hypothesis could be assessed by isolectin injection through the tail-vein where isolectin was taken up only by the EET-impregnated plug. Moreover ultrasound measurements revealed accumulation of contrast agent in EET impregnated plugs compared to control plugs. Taken together our findings emphasize that CYP2C plays a crucial role in the vessel formation process by modulating the effects mediated by two important control elements of the angiogenic response, namely VEGF and EphB4. CYP2C-derived EETs not only participate as second messengers in the angiogenic response, but have the potential to influence much more than angiogenesis by enhancing smooth muscle cell/pericyte recruitment to endothelial cell tubes to promote vascular maturation.
Although Walter Benjamin was never timid when it came to writing, one practice he consistently avoided was that of creating neologisms. It is therefore with all the more reluctance that I find myself compelled to resort to something similar, in order to sum up a motif that has imposed itself over the years in my reading of Benjamin. What is involved is, to be sure, not exactly a neologism, since it does not involve the creation of a new word, but rather the highlighting of a word-part, a suffix (eine Nachsilbe). In English, to be sure, this suffix, when spoken, is indistinguishable from a word: what distinguishes it from a word is not audible, but only legible: a hyphen, marking a separation that is also a joining, a 'Bindestrich' that does not bind it to anything in particular and yet that requires it to be bound to something else. The suffix in question thus sounds deceptively familiar, since it coincides, audibly, with the word "abilities". However, unlike that word, its first letter - which purely by accident happens to be the first letter of the alphabet--is preceded by a dash. When written in isolation, this gives it a somewhat bizarre appearance, to be sure, since suffixes are not usually encountered separately from the words they modify. But this bizarre appearance pales when compared to its German 'original'. If the book of essays to be published in English under the title, "Benjamin’s -abilities," is ever translated into German - "back" into German I was tempted to write, since German here is of course the language in which Benjamin wrote and in which I generally read him - then its title, were it to be entirely faithful to the English, would indeed have to involve the creation of a neologism. For translated back into German, the German title would require its readers to "read, what was never written", namely: "Benjamins -barkeiten" (written, "Bindestrich- b--kleingeschrieben").
Religious conversion has become a dangerous social and individual problem. In Latin America, a traditional Catholic area, Protestant sects are successfully con-verting more and more Catholics into their own communities. Therefore the Pope demands a strict control of these activities. In India e.g., the Catholic hierarchy is critizising the Indian governments which have forbidden conversion on non-spiritual reasons. Hindu organizations have started even very successfully to re-convert Indian Christians particularly of Dalit and tribal background. Buddhists are very successful in indirect and even direct conversion of many Westerners. Wah-habit missionaries spread their Neo-Islam in the Muslim societies and get more and more even non-Muslim converts. We should add the forcible and sometimes ex-tremely cruel conversions the atheistic states had executed since the last century. ...
What is the energy function guiding behavior and learningµ Representationbased approaches like maximum entropy, generative models, sparse coding, or slowness principles can account for unsupervised learning of biologically observed structure in sensory systems from raw sensory data. However, they do not relate to behavior. Behavior-based approaches like reinforcement learning explain animal behavior in well-described situations. However, they rely on high-level representations which they cannot extract from raw sensory data. Combinations of multiple goal functions seems the methodology of choice to understand the complexity of the brain. But what is the set of possible goals. ...
Background This study was carried out to compare the HRQoL of patients in general practice with differing chronic diseases with the HRQoL of patients without chronic conditions, to evaluate the HRQoL of general practice patients in Germany compared with the HRQoL of the general population, and to explore the influence of different chronic diseases on patients HRQoL, independently of the effects of multiple confounding variables. Methods A cross-sectional questionnaire survey including the SF-36, the EQ-5D and demographic questions was conducted in 20 general practices in Germany. 1009 consecutive patients aged 15–89 participated. The SF-36 scale scores of general practice patients with differing chronic diseases were compared with those of patients without chronic conditions. Differences in the SF-36 scale/summary scores and proportions in the EQ-5D dimensions between patients and the general population were analyzed. Independent effects of chronic conditions and demographic variables on the HRQoL were analyzed using multivariable linear regression and polynomial regression models. Results The HRQoL for general practice patients with differing chronic diseases tended to show more physical than mental health impairments compared with the reference group of patients without. Patients in general practice in Germany had considerably lower SF-36 scores than the general population (P < 0.001 for all) and showed significantly higher proportions of problems in all EQ-5D dimensions except for the self-care dimension (P < 0.001 for all). The mean EQ VAS for general practice patients was lower than that for the general population (69.2 versus 77.4, P < 0.001). The HRQoL for general practice patients in Germany seemed to be more strongly affected by diseases like depression, back pain, OA of the knee, and cancer than by hypertension and diabetes. Conclusion General practice patients with differing chronic diseases in Germany had impaired quality of life, especially in terms of physical health. The independent impacts on the HRQoL were different depending on the type of chronic disease. Findings from this study might help health professionals to concern more influential diseases in primary care from the patient´s perspective.
Background: This article reports on the relationship between cultural influences on life style, coping style, and sleep in a sample of female Portuguese immigrants living in Germany. Sleep quality is known to be poorer in women than in men, yet little is known about mediating psychological and sociological variables such as stress and coping with stressful life circumstances. Migration constitutes a particularly difficult life circumstance for women if it involves differing role conceptions in the country of origin and the emigrant country.
Methods: The study investigated sleep quality, coping styles and level of integration in a sample of Portuguese (N = 48) and Moroccan (N = 64) immigrant women who took part in a structured personal interview.
Results: Sleep quality was poor in 54% of Portuguese and 39% of Moroccan women, which strongly exceeds reports of sleep complaints in epidemiologic studies of sleep quality in German women. Reports of poor sleep were associated with the degree of adoption of a German life style. Women who had integrated more into German society slept worse than less integrated women in both samples, suggesting that non-integration serves a protective function. An unusually large proportion of women preferred an information-seeking (monitoring) coping style and adaptive coping. Poor sleep was related to high monitoring in the Portuguese but not the Moroccan sample.
Conclusion: Sleep quality appears to be severely affected in women with a migration background. Our data suggest that non-integration may be less stressful than integration. This result points to possible benefits of non-integration. The high preference for an information-seeking coping style may be related to the process of migration, representing the attempt at regaining control over an uncontrollable and stressful life situation.
This thesis deals with the analysis of “presolar” silicates and oxides by high resolution mass spectrometry and electron microscopy techniques. This “stardust” was identified by its extreme oxygen isotopic anomalies, which point to nucleosynthetic reactions in stellar interiors, in the carbonaceous chondrite Acfer 094. Isotopic, chemical and mineralogical studies on these stardust grains therefore allow the testing of astrophysical questions on Earth, which are otherwise only accessible by spectroscopy and theoretical models. The class of presolar silicates has been identified only six years ago in 2002, although it was known already from spectroscopic observations that silicates represent the most abundant type of dust in the galaxy. The development of the “NanoSIMS” was a crucial step in this respect, because this ion probe with its superior spatial resolution of only 50 nm allowed the detection of the typically 300 nm sized presolar silicates. A total of 142 presolar silicates and 20 presolar oxides were identified within Acfer 094, whose matrix therefore contains 163 ± 14 ppm presolar silicates and 26 ± 6 ppm presolar oxides. This is among the highest amounts reported so far for any primitive solar system material. The majority of detected stardust grains derive from asymptotic giant branch stars of 1 – 2.5 Msun and close-to-solar or slightly lower-than-solar metallicity. However, by measuring the Si isotopic compositions of some enigmatic grains, it could be shown that there is a sub-class of presolar silicates characterized by an extreme enrichment of 17O and a moderate enhancement of 30Si relative to solar, whose origins might be explained by formation in binary stellar systems. About 10% of all grains exhibit an enrichment in 18O and some of them also of 28Si relative to solar, which most likely point to an origin in type II supernova explosions. The Si isotopic measurements also allowed to quantify the effect of the s-process on the Si isotopes in low-mass asymptotic giant branch stars. The results agree well with theoretical predictions. The grains were furthermore characterized by SEM and the chemistries of about half of the grains were determined by Auger electron spectroscopy. The majority of grain morphologies are consistent with what is expected from condensation experiments. However, a lot of grains are altered by Fe-rich minerals, which are either of primary condensation or of secondary ISM or solar nebula origin. Furthermore, complex presolar grains consisting of refractory Al-rich grains attached to silicate material could be identified, which have been predicted by condensation theory and observational evidence. Nine presolar silicates were analyzed by combined NanoSIMS/TEM studies. The majority of grains are Mg-rich and amorphous, which is in contrast to astrophysical evidence, which mainly postulate crystalline Mg-rich and amorphous Fe-rich circumstellar condensates. However, the grains might have been rendered amorphous by secondary processes in the ISM or could have condensed under non-equilibrium, low-temperature conditions in the circumstellar outflow. The grains are more likely characterized by a variable, pyroxene-like chemistry, which could be a result of sputtering in the ISM, which preferentially removes Mg. The detected crystalline presolar silicates in this study and in other work are all olivines, whereas grains with a pyroxene stoichiometry are all amorphous except one. This supports astrophysical models which point to different formation pathways for these two types of grains and therefore different crystallinity. However, the relatively high Fe content of three detected presolar olivines in this study and in other work is in contrast to astrophysical evidence and theoretical considerations, which predict essentially Fe-free crystalline grains. It is therefore possible that the infrared spectra might also be compatible with less Mg-rich olivines. The only crystalline presolar silicate with a pyroxene-like stoichiometry is the unusual grain 1_07: although it is chemically enstatite, the electron diffraction pattern could only be indexed to silicate perovskite, which is stable above ~23 GPa. The discovery of a high-pressure phase of presolar origin shows that dust grains encountering interstellar shocks might not necessarily be completely destroyed. In astrophysical models it is in principle also possible that a fraction of larger grains might survive such a shock wave encounter as a high-pressure modification, which is supported by this discovery.
Motivated by the recent discussion of the declining importance of deposits as banks´ major source of funding we investigate which factors determine funding costs at local banks. Using a panel data set of more than 800 German local savings and cooperative banks for the period from 1998 to 2004 we show that funding costs are not only driven by the relative share of comparatively cheap deposits of bank´s liabilities but among other factors especially by the size of the bank. In our empirical analysis we find strong and robust evidence that, ceteris paribus, smaller banks exhibit lower funding costs than larger banks suggesting that small banks are able to attract deposits more cheaply than their larger counterparts. We argue that this is the case because smaller banks interact more personally with customers, operate in customers´ geographic proximity and have longer and stronger relationships than larger banks and, hence, are able to charge higher prices for their services. Our finding of a strong influence of bank size on funding costs is also in an in- ternational context of great interest as mergers among small local banks - the key driver of bank growth - are a recent phenomenon not only in European banking that is expected to continue in the future. At the same time, net interest income remains by far the most important source of revenue for most local banks, accounting for approximately 70% of total operating revenues in the case of German local banks. The influence of size on funding costs is of strong economic relevance: our results suggest that an increase in size by 50%, for example, from EUR 500 million in total assets to EUR 750 million (exemplary for M&A transactions among local banks) increases funding costs, ceteris paribus, by approximately 18 basis points which relates to approx. 7% of banks´ average net interest margin.
This paper is one of the first to analyse political influence on state-owned savings banks in a developed country with an established financial market: Germany. Combining a large dataset with financial and operating figures of all 457 German savings banks from 1994 to 2006 and information on over 1,250 local elections during this period we investigate the change in business behavior around elections. We find strong indications for political inflence: the probability that savings banks close branches, lay-off employees or engage in merger activities is significantly reduced around elections. At the same time they tend to increase their extraordinary spendings, which include support for social and cultural events in the area, on average by over 15%. Finally, we find that savings banks extend significantly more loans to their corporate and private customers in the run-up to an election. In further analyses, we show that the magnitude of political influence depends on bank specific, economical and political circumstances in the city or county: political influence seems to be facilitated by weak political majorities and profitable banks. Banks in economically weak areas seem to be less prone to political influence.
The relation between reality and language, the instability of language as a signification system, the representation crisis, and the borders of interpretation are the controversial issues that have engaged not only philosophers, but also many authors, translators, and literary critics. Some philosophers like Derrida accuse Western thinking of being obsessed with binary oppositions. In Derrida's view, Western tradition resorts to external references as God, truth, origin, center and reason to stabilize the signification system. Since these concepts lack an internal sense and there is no transcendental signified that can fix these signifiers, language turns to an instable system by means of which no fixed meaning can be created. Many authors like Beckett, Stoppard, and Caryl Churchill also noticed this impossibility of language. While Derrida's deconstructive approach to this crisis has an epistemological nature, these playwrights present an aesthetic solution by turning the deconstructive potential of language against itself in text and performance. This dissertation aims at exploring their performing methods and dramatic texts to demonstrate how their delogocentric strategies work. By analyzing their plays, I will examine if their use of signifiers that have no references in reality, intentional misconceptions, disintegrated subjectivities, decentered narratives, and experimental performances can help them undermine the prevailing logocentrism of Western thought. The examination of the change in aesthetic strategies from Beckett, who belongs to earlier stages of post modernism, to Caryl Churchill, who should perform in a globalized world with increasing dominance of speed and information, is another aim of this research. In my view,Beckett's obsession with unspeakable, absurdity, and disintegration of subjectivity develops to Stoppard's language games, metadrama, and anti-representation and culminates in Churchill's anti-narrative texts and pluralistic performances. The monophony of Beckett's dramatic texts is replaced by the polyphony of Churchill's performances, which are a mixture of theater, dance and music. However, all explored dramatic texts in this dissertation have something in common: they are language games, which have no claim on a faithful representation of reality or transcendental truth.
Poster presentation: Purpose of the study First-line HAART with tenofovir DF (TDF) and FTC in pivotal trials has been associated with high efficacy and good tolerability. However, real-life clinical practice often differs from clinical trials due to co-morbidities, co-infections, and less intensive clinical monitoring. To evaluate efficacy and safety of first-line HAART in a day-to-day setting, this Gilead-sponsored non-interventional cohort was established. Methods Between July 2005 and August 2006, 533 HIV-1 infected antiretroviral-naïve patients from 50 German centres enrolled in this non-interventional cohort. All patients were followed every 3 months for 3 years to monitor efficacy (viral load [VL], CD4), tolerability, renal safety, regimen changes and resistance profile. All patients received TDF+FTC as a single tablet (Truvada, TVD) in combination with either an NNRTI or PI/r as their first antiretroviral regimen. Summary of results As of June 2008, 2 years of therapy have been documented for 330/533 (62%) patients. At treatment initiation, 81% were male; median age was 39 years; clinical AIDS diagnosis was documented in 22%; 47% started therapy with CD4 <200 cells/mm3. TVD was combined with an NNRTI (43%) or a PI/r (57%). After 24 months, in an As-Treated (AT) analysis, 85% patients achieved a VL <50 copies/ml (VL <500 copies/ml: 97%), median CD4 count increased from 217 at baseline to 450 cells/mm3 (IQR: 325–608). Truvada showed a good safety profile; 76 adverse events (AEs) of any grade were reported in 66/533 patients (12%); six of these were judged serious. Fourteen (2.6%) patients discontinued TVD due to AEs. Renal abnormalities of any grade were reported in 10 patients (1.9%). Virological failure was documented in nine patients, of which eight were genotyped; M184V/I was detected in three, K65R in two patients. Conclusion During 2 years of follow-up, the overall safety of TVD was good; renal AEs of any grade were reported in 1.9% of patients. K65R was detected in two patients. First-line HAART with TVD plus an NNRTI or PI/r in clinical practice showed comparable efficacy to that observed in controlled clinical trials.
Predicate complements
(2008)
This paper considers a trading game in which sequentially arriving liquidity traders either opt for a market order or for a limit order. One class of traders is considered to have an extended trading horizon, implying their impatience is linked to their trading orientation. More specifically, sellers are considered to have a trading horizon of two periods, whereas buyers only have a single-period trading scope (the extended buyer-horizon case is completely symmetric). Clearly, as the life span of their submitted limit orders is longer, this setting implies sellers are granted a natural advantage in supplying liquidity. This benefit is hampered, however, by the direct competition arising between consecutively arriving sellers. Closed-form characterizations for the order submission strategies are obtained when solving for the equilibrium of this dynamic game. These allow to examine how these forces affect traders´ order placement decisions. Further, the analysis yields insight into the dynamic process of price formation and into the market clearing process of a non-intermediated, order driven market.
Pidgin English is the chief medium of communication for the great majority of Cameroonians. It sustains a world view, culture and way of life. Pidgin embodies concepts that would at best be partially expressed in formal English. A critical understanding of Pidgin English requires not only a thorough grasp of the socio-cultural matrix from which the words and expressions originate but also an immersion in an Afro-centric worldview. Majunga Tok: Poems in Pidgin English is the poet's attempt at capturing these speech patterns of ordinary Cameroonians in written form. Pidgin English, also called broken English, is a lingua franca spoken not only in Cameroon but also in many West African countries, including Nigeria, Ghana, Sierra Leone and Liberia amonst others. This poetry anthology is inspired by the poet's desire to salvage a language that has been subjected to multiple forms of denigration because it is oral. In Cameroon, for instance, Pidgin English has been the target of myriad attacks from self-styled linguistic purists who claim that Pidgin is a bastardized variant of Standard English and, therefore, should not be allowed to thrive. The controversy and denigration directed at Amos Tutuola and his Pidgin English creative genius are vivid examples. This condescending attitude of speakers of Standard English stems from the fact that Pidgin is often associated with illiteracy.
Green Rape: Poetry for the Environment is an anthology of poems written in strong support of environmental literacy. Each poem is the poet's cry of protest against the rape of natural and built environments. The anthology examines a wide range of issues including the clash of global capitalism with environmental activism. It takes a close look at the major themes in international discourse on environmental degradation, climate change, renewable energy sources, global warming, Gene technology, biodiversity and more. The poet dispels a number of myths, notably the existence of an inexhaustible bank of natural resources at the disposal of Man. He attempts to provide a solution to the abusive and unbalanced utilization of scarce natural resources. In a unique way, the poems contribute to the fostering of environmental awareness that would contribute to the sustainable management of natural resources. The poet invites us to look beyond the doomsday rhetoric about the state of the environment and to commit more of our resources where they will do the most good to lifting the world's population out of poverty. The significance of this anthology to environmental education resides in its contribution to the debate on global sustainable development, especially efforts to protect the environment and eradicate poverty.
No Love Lost
(2008)
No Love Lost is a tale of troubled times in which the storyteller strives to return to wholesomeness a society whose values have jumped the rail. Set in the 'No Man's Land' of Ongola, the novel unravels the corruption and influence-peddling endemic in this African country. Framed around the travails of an unemployed university graduate, the story is the gripping depiction of one man's vendetta against a society at odds with itself. Among others, the novel explores the themes of identity crisis, political gerrymandering, individual and collective greed, love and marriage, and class exploitation to weave an enduring tapestry of great human interest. Written against the backdrop of nascent neo-colonialism No Love Lost combines the traditional and the modern; the private and the public to demonstrate that the quest for truth and justice behooves all and sundry. The author infuses the narrative with oral traditions to capture the reader's attention in a compelling style. This is a refreshing work by a writer whose heart throbs for his people and their plight.
Grassfields Stories from Cameroon is an anthology of short stories. It comprises animal trickster tales, bird survival tales, and human-interest stories. The compendium is a reflection of the mores, cultures, and value systems of the indigenous peoples of the Northwest Province of Cameroon. It is motivated by the author's keen interest in the preservation of Cameroonian oral traditions in written form. These stories deal with the day-to-day life of the sedentary and the globe-trotter. Each story is sufficient onto itself. The author has intentionally avoided chronology in the order of presentation of the stories. Whether you read the stories in the order in which they are presented or dart about as your fancy dictates, you will feel the abundance of richness and entertainment the book contains. The didactic value of this collection of short stories resides in its suitability to readers of all age groups. The uniqueness of the volume lies in its universal appeal. Peter Wuteh Vakunta was born and raised in the village of Bamunka-Ndop in Cameroon where he worked as senior translator at the Presidency of the Republic before immigrating to America. He is an alumnus of Sacred Heart College-Mankon. Vakunta obtained his Bachelor degrees in Cameroon and Nigeria; MA and MSE degrees in Cameroon and the U.S.A. At present, Vakunta and his family live in Madison, U.S.A. He teaches in the Department of French and Italian at the University of Wisconsin-Madison where he is also completing his PhD dissertation titled: Translation in Literature: Indigenization in the Francophone Text. Vakunta is poet, storyteller and essayist. His published works include Better English: Mind Your P's and Q's, Lion Man and Other Stories (short stories), Brainwaves (poems), Pandora's Box (poems). African Time and Pidgin Verses (poems), Square Pegs in Round Holes (essays) and It Takes Guts (essays). Vakunta's literary works have earned him several awards in the U.S.A, U.K and Africa.
Cry My Beloved Africa is a compendium of essays having as locus the continent of Africa. It comprises insightful observations on the politics, governmental systems, political economy, cultural practices, educational systems and natural phenomena that impact on the lives of Africans. True to the tradition of French novelist Stendhal, the author intends this work to serve as a mirror that reflects the day-to-day living of the different peoples that inhabit the fifty-three nation-states in Africa. It is directed to contemporary Africa and to the relationship between Africa and the rest of the globe. The didactic value of the book resides in its suitability to the young and the old. The language is clear and free of sophistry.
A new species, Aiolopus obariensis sp. n., is described and illustrated from Fezzan Province, Libya. Besides other differentiating characters, the new species is characterized by having a conspicuously short and club-shaped left antenna. A description and a key to Libyan species of Aiolopus Fieber is provided. Some additional characters of male and female genitalia have also been incorporated.
Taxonomic, systematic, and biogeography knowledge on the Palaearctic species of Pristaulacus Kieffer 1900 is summarized. Twenty-one valid species are recognized. The most important morphological characters taken into consideration are: shape, cuticular sculpture, and pubescence of head; index length/width of antennomeres; shape, sculpture and cuticular processes of mesosoma, especially of pronotum and mesonotum; number and shape of teeth on claw; shape and sculpture of metasoma; ovipositor length compared with wing and antenna length; and colour pattern (e.g., the dark spots on fore wing, and the colour of hind tarsus). Several characters of the genital capsule of the male were proved to be very useful for species identification, e.g., the shape of the paramere, volsella, cuspis, and digitus. Based on analysis of twenty-five morphological characters, eight species groups are recognized. The critical revision of the chorological data, including many new records, introduced relevant changes of the geographical distribution pattern of most species. Twelve species are restricted to the western part of the Palaearctic Region and eight species are restricted to its eastern part; only one species, P. gibbator, has a wider distribution, including both western and eastern parts of the Palaearctics.
The epithelial absorbing cells of the small intestinal villi, the enterocytes, are the main protagonists for the transport of nutrients from the intestinal lumen to the interstitial fluids. The oriented flow of nutrients is carried out by different and complementary transport systems present in the apical and the basolateral domains of the enterocyte’s plasma membrane. One of the distinctive characteristics of those intestinal cells is the presence of numerous structurally distinct protrusions (referred as microvilli) on the apical surface of the plasma membrane. They confer the brush-like appearance of the microvillus border (commonly referred to as the "brush border") typically observed in the light microscope. Over the years, there has been considerable interest to study the molecular mechanisms driving the transport of molecules across the intestinal brush border membrane (BBM). Defects have been described to cause a variety of pathological conditions, such as disorders in the metabolism of saccharides (glucose and galactose malabsorption, lactose intolerance), amino acids (Hartnup disease, aminoacidurias), ions (sodium and potassium in the case of familiar diarrhea), metals (zinc in acrodermatitis enteropathica) and cholesterol lipids (cardiovascular diseases). In particular, the essential role of the BBM in regulating the delicate balance between cholesterol influx and efflux from the lumen to the enterocyte has been recently highlighted through the genetic analysis of individuals suffering of cholesterol disorders as well as in several clinical studies involving the use of dietary plant sterols (phytostrerols) or specific protein inhibitors blocking essential components of the cholesterol absorption/resorption pathway. ...
This paper proposes a representation for syllable structure in HPSG, building on previous work by Bird and Klein (1994), Höhle (1999), and Crysmann (2002). Instead of mapping segments into a a separate part of the sign where syllables are represented structurally, information about syllabification is encoded directly in the list of segments, the core of the PHONOLOGY value. Higher level prosodic phenomena can operate on a more abstract representation of the sequence of syllables derived from the syllabified segments list. The approach is illustrated with analyses of some word-boundary phenomena conditioned by syllable structure in French.
Three-dimensional structure of the glycine-betaine transporter BetP by cryo electron crystallography
(2008)
The soil bacterium Corynebacterium glutamicum has five secondary transporters for compatible solutes allowing it to cope with osmotic stress. The most abundant of them, the transporter BetP, performs a high affinity uptake of glycine-betain when encountering hyperosmotic stress. BetP belongs to the betaine/carnitine/choline/transporter (BCCT) family, and is predicted to have twelve transmembrane helices with both termini facing the cytoplasm. The goal of this thesis is to facilitate understanding of BetP function by determining a three dimensional (3D) model of its structure. Two-dimensional (2D) crystallization of wild-type (WT) BetP has been successfully performed by reconstitution into a mixture of E. coli lipids and bovine cardiolipin, which resulted in vesicular crystals diffracting to 7.5 Å resolution (Ziegler, Morbach et al. 2004). Diffraction patterns of these crystals however showed unfocused spots, generally due to high mosaicity. Better results were obtained by using the constitutively active mutant BetPdeltaC45 in which the first 45 amino acids of the positively charged C-terminus were removed. BetPdeltaC45 crystals obtained under the same conditions for BetP WT were concluded to be pseudo crystals, based on the inconsistence of symmetry. These crystals had BetPdeltaC45 molecules randomly up/downwards inserted into membrane crystals, and cannot be used for structure determination, even though they diffracted up to 7 Å. The problem of pseudo crystal formation could be solved by changing the lipids used for 2D crystallization to a native lipid extract from C. glutamicum cells. This change of lipids improved the crystals to well-ordered packing with exclusive p121_b symmetry. To understand the role of lipids in crystal packing and order, lipids were extracted at different stages during crystallization, and identified by using multiple precursor ion scanning mass spectrometry. The results show that phosphatidyl glycerol (PG) 16:0-18:1 is the most dominant lipid species in C. glutamicum membranes, and that BetP has a preference for the fatty acid moieties 16:0-18:1. Crystallization with synthetic PG 16:0-18:1 proved that an excess of this lipid prevents pseudo crystal formation, but these crystals did not reach the quality as previously achieved by using the C. glutamicum lipids. Apart from the effect of lipids in crystallinity, the concentration and type of salts influenced crystal growth and morphology. High salt conditions (>400 mM LiCl or KCl) yielded tubular crystals, whereas low salt conditions (<300 mM LiCl, NaCl or KCl) led to formation of up to 10 µm large sheet-like crystals. The intermediate concentration gave a mixture of sheet-like and tubular crystals. In terms of resolution, sheets diffracted better than tubes. The sheet-like crystals used for 3D map reconstruction were obtained from a dialysis buffer containing 200 mM NaCl combined with using C. glutamicum lipids. Electron microscopic images were taken from frozen-hydrated crystals using a helium-cooled JEOL 300 SFF microscope or a liquid nitrogen-cooled FEI Tecnai G2 microscope at 300 kV, which allowed optimal data collection and minimized radiation damage to the sample. More than 1000 images of tilt angles up to 50° were taken and evaluated using optical diffraction of a laser beam. The best 200 images were processed with the MRC image processing software package, and 79 images from different tilt angles were merged to the final data set used for calculation of a 3D map at a planar resolution of 8 Å. The structure shows BetPdeltaC45 as a trimer with each monomer consisting of 12 transmembrane alpha-helices. Protein termini and loop regions could not be determined due to the limited resolution of the map. Six of the twelve helices line a central cavity forming a potential substrate-binding chamber. Each monomer shows a central cavity in different sizes and shapes. Thus, the constitutively active BetPdeltaC45 thus forms an unusual asymmetric homotrimer. BetP most likely reflects three different conformational states of secondary transporters: the cytoplasmically open (C), the occluded (O), and the periplasmically open (P) states. The C and O states are similar to BetP WT projection structure, while the P state is discrepant and highly flexible due to the shape and size of the central cavity as well as the lowest intensity of the density. The observation of the P state corresponds well to the constitutively active property of BetPdeltaC45. For the high resolution structure of the C and O states are available, this work presents the first structural information of the P state of a secondary transporter.
A novel experimental approach for studying exotic transitions in few-electron high-Z ions was developed. In this approach, few-electron ions with selectively produced single K-shell holes are used for the investigation of the transition modes that follow the decay of the excited ions. The feasibility of the developed approach was confirmed by an experimental study of the production of low-lying excited states in He-like uranium, produced by K-shell ionization of initially Li-like species. It was found that K-shell ionization is a very selective process that leads to the production of only two excited states, namely the 1s2s 21S0 and 1s2s 23S1. This high level of selectivity stays undisturbed by the rearrangement processes. These experimental findings can be explained using perturbation theory and an independent-particle model, and are a result of the very different impact parameter dependencies of K-shell ionization and L- intrashell excitation. The L-shell electron can be assumed to stay passive in the collision, whereas the K-shell electron is ionized. It was stressed that the current result might directly be applied to accurate studies of the two-photon decay in He-like ions. Up to now, the experimental challenge in conventional 2E1 experiments has been the photon-photon coincidence technique, which is required to separate the true 2E1 events from the x-ray background associated with single photon transitions. In contrast, by exploiting K-shell ionization, the spectral distribution of the two-photon decay could be obtained simply by a measurement of the photon emission, using only a single x-ray detector in coincidence with projectile ionization. One further particular advantage arises from the fact that the 1s2p 3P0 state is not populated, and does not contribute to the continuum distribution of the two-photon emission. At high Z, this state also undergoes a two-photon E1M1 decay, which would be indistinguishable from the 2E1 decay of the 1s2s 1S0. The first measurement of the two-photon energy distribution from the decay of 1s2s 1S0 level in He-like tin was performed by adopting the technique developed in this thesis. In this technique, excited He-like heavy ions were formed by K-shell ionization of initially Li-like species in collisions with a low-Z gas target, and x-ray spectra following the decay of the He-like ions were measured in coincidence with the up-charged tin ions. The observed intense production of the 2E1 transitions, and a very high level of selectivity, make this process particularly suited for the study of the two-photon continuum, and thus for a detailed investigation of the structure of high-Z He-like systems. The method allowed for a background-free measurement of the distribution of the two-photon decay (21S0 -> 11S0) in He-like tin. The measured distribution could also be discriminated from that of other He-like ions, and confirmed, for the first time, the fully relativistic calculations. In addition, the feasibility of the method was confirmed by studying another exotic transition, namely the two-electron one-photon transition (TEOP) in Li-like high-Z ions. An experimental investigation of the radiative decay modes of the 1s2s2 state in Li-like heavy ions has been started. In the first dedicated beam time at the ESR, selective population of this state via K-shell ionization of initially Be-like species was achieved. The x-rays produced in this process were measured by a multitude of x-ray detectors, each placed under different observation angles with respect to the ion beam direction. The spectra associated with projectile electron loss consist (in all cases) of one single x-ray transition, which was attributed to the TEOP decay to the 1s2 2p1/2 level, possibly contaminated by the M1 decay to the 1s22s. Thus it was proven that, by adopting the developed approach, one can indeed produce the desired initial state. This makes this method perfectly suited for studies of TEOP transitions in high-Z systems. An extension of this study, by the inclusion of an electron spectrometer, would also allow for measurements of the autoionization channel, which would provide complete information on the various decay modes of the 1s2s2 state.
Impact of protected areas and land use on regeneration of Acacia woodland’s in Eastern Burkina Faso
(2008)
Regeneration success, persistence strategies (seedlings vs. coppicing), and population trend of Acacia spp. were tested under two land-use regimes in eastern Burkina Faso: (i) protected areas shielded to livestock grazing pressure, to logging, and using early annual fire as a management system; (ii) areas with high human impact (heavily and extensive livestock grazing, harvesting for wood and for medicinal plants). Generally, a good regeneration rate of Acacia species was observed in protected areas and a poor regeneration rate in areas with high human impact. Nevertheless, some species affiliated to the subgenus Aculeiferum as A. dudgeoni and A. polyacantha showed a good regeneration under both land use regimes. Juvenile plants less than 25 cm height of A. dudgeoni and A. gourmaensis increased by 116 to 50 % in areas with human impact as compared to their populations in protected areas. With SCD slopes varying from –0.40 to -0.70, the protected Acacia woodland displayed a stable population structure due to abundance of recruitment, and coppicing persistence (more common in the subgenus Aculeiferum) favoured by early annual fire. Consequently, the protected areas are favourable for Acacia woodland regeneration. Conversely, SCD slopes are positive or close to zero in areas of anthropogenic regime and showed a declining population, especially more marked with the subgenus Acacia due to permanent seed and seedling removal by livestock grazing. Nevertheless, the number of seedlings of some species was higher in areas under human pressure than in protected areas, especially for the subgenus Aculeiferum, improving the genetic variability and thus the long-term maintenance of the population. Key words: Acacia, early fire, land use, sudano-sahelien zone
We argue that Clustering in heavy ion collisions could be the missing element in resolving the socalled HBT puzzle, and briefly discuss the different physical situations where clustering could be present. We then propose a method by which clustering in heavy ion collisions could be detectedin a model-independent way.
The purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, interindividual, randomized study design, both contrast agents were compared in a total of 471 patients regarding their diagnostic accuracy, sensitivity, and specificity to correctly classify focal lesions of the kidney. To test for noninferiority the diagnostic accuracy rates for both contrast agents were compared with CT results based on a blinded reading. The average diagnostic accuracy across the three blinded readers (‘average reader’) was 83.7% for gadobutrol and 87.3% for gadopentate dimeglumine. The increase in accuracy from precontrast to combined precontrast and postcontrast MRI was 8.0% for gadobutrol and 6.9% for gadopentate dimeglumine. Sensitivity of the average reader was 85.2% for gadobutrol and 88.7% for gadopentate dimeglumine. Specificity of the average reader was 82.1% for gadobutrol and 86.1% for gadopentate dimeglumine. In conclusion, this study documents evidence for the noninferiority of a single i.v. bolus injection of 1.0 M gadobutrol compared with 0.5 M gadopentate dimeglumine in the diagnostic assessment of renal lesions with CE-MRI.
Chemical ozone loss in winter 1991–1992 is recalculated based on observations of the HALOE satellite instrument, Version 19, ER-2 aircraft measurements and balloon data. HALOE satellite observations are shown to be reliable in the lower stratosphere below 400 K, at altitudes where the measurements are most likely disturbed by the enhanced sulfate aerosol loading, as a result of the Mt.~Pinatubo eruption in June 1991. Significant chemical ozone loss (13–17 DU) is observed below 380 K from Kiruna balloon observations and HALOE satellite data between December 1991 and March 1992. For the two winters after the Mt. Pinatubo eruption, HALOE satellite observations show a stronger extent of chemical ozone loss towards lower altitudes compared to other Arctic winters between 1991 and 2003. In spite of already occurring deactivation of chlorine in March 1992, MIPAS-B and LPMA balloon observations indicate that chlorine was still activated at lower altitudes, consistent with observed chemical ozone loss occurring between February and March and April. Large chemical ozone loss of more than 70 DU in the Arctic winter 1991–1992 as calculated in earlier studies is corroborated here.
Background: The hemagglutinin (HA) glycoprotein is the principal target of protective humoral immune responses to influenza virus infections but such antibody responses only provide efficient protection against a narrow spectrum of HA antigenic variants within a given virus subtype. Avian influenza viruses such as H5N1 are currently panzootic and pose a pandemic threat. These viruses are antigenically diverse and protective strategies need to cross protect against diverse viral clades. Furthermore, there are 16 different HA subtypes and no certainty the next pandemic will be caused by an H5 subtype, thus it is important to develop prophylactic and therapeutic interventions that provide heterosubtypic protection. Methods and Findings: Here we describe a panel of 13 monoclonal antibodies (mAbs) recovered from combinatorial display libraries that were constructed from human IgM+ memory B cells of recent (seasonal) influenza vaccinees. The mAbs have broad heterosubtypic neutralizing activity against antigenically diverse H1, H2, H5, H6, H8 and H9 influenza subtypes. Restriction to variable heavy chain gene IGHV1-69 in the high affinity mAb panel was associated with binding to a conserved hydrophobic pocket in the stem domain of HA. The most potent antibody (CR6261) was protective in mice when given before and after lethal H5N1 or H1N1 challenge. Conclusions: The human monoclonal CR6261 described in this study could be developed for use as a broad spectrum agent for prophylaxis or treatment of human or avian influenza infections without prior strain characterization. Moreover, the CR6261 epitope could be applied in targeted vaccine strategies or in the design of novel antivirals. Finally our approach of screening the IgM+ memory repertoire could be applied to identify conserved and functionally relevant targets on other rapidly evolving pathogens.
Australophanus, new genus, is described and illustrated for Cryptamorpha redtenbacheri (Reitter). Platamus Erichson is synonymized under Telephanus Erichson, new synonymy. Euplatamus Sharp, new status, replaces Platamus Erichson as the genus name. Type species are designated for Aplatamus Grouvelle and Euplatamus Sharp. Telephanus velox (Haldeman) is synonymized under Telephanus atricapillus Erichson. A diagnosis of the tribe Telephanini, a key to the described telephanine genera of the world is presented, and a phylogeny of the family Silvanidae is proposed.
A graph theoretical approach to the analysis, comparison, and enumeration of crystal structures
(2008)
As an alternative approach to lattices and space groups, this work explores graph theory as a means to model crystal structures. The approach uses quotient graphs and nets - the graph theoretical equivalent of cells and lattices - to represent crystal structures. After a short review of related work, new classes of cycles in nets are introduced and their ability to distinguish between non-isomorphic nets and their computational complexity are evaluated. Then, two methods to estimate a structure’s density from the corresponding net are proposed. The first uses coordination sequences to estimate the number of nodes in a sphere, whereas the second method determines the maximal volume of a unit cell. Based on the quotient graph only, methods are proposed to determine whether nets consist of islands, chains, planes, or penetrating, disconnected sub-nets. An algorithm for the enumeration of crystal structures is revised and extended to a search for structures possessing certain properties. Particular attention is given to the exclusion of redundant nets and those, which, by the nature of their connectivity, cannot correspond to a crystal structure. Nets with four four-coordinated nodes, corresponding to sp3 hybridised carbon polymorphs with four atoms per unit cell, are completely enumerated in order to demonstrate the approach. In order to render quotient graphs and nets independent from crystal structures, they are reintroduced in a purely graph-theoretical way. Based on this, the issue of iso- and automorphism of nets is reexamined. It is shown that the topology of a net (that is the bonds in a crystal) constrains severely the symmetry of the embedding (that is the crystal), and in the case of connected nets the space group except for the setting. Several examples are studied and conclusions on phases are drawn (pseudo-cubic FeS2 versus pyrite; α- versus β- quartz; marcasite- versus rutile-like phases). As the automorphisms of certain quotient graphs stipulate a translational symmetry higher than an arbitrary embedding of the corresponding net would show, they are examined in more detail and a method to reduce the size of such quotient graphs is proposed. Besides two instructional examples with 2-dimensional graphs, the halite, calcite, magnesite, barytocalcite, and a strontium feldspar structures are discussed. For some of the structures it is shown that the quotient graph which is equivalent to a centred cell is reduced to a quotient graph equivalent to the primitive cell. For the partially disordered strontium feldspar, it is shown that even if it could be annealed to an ordered structure, the unit cell would likely remain unchanged. For the calcite and barytocalcite structures it is shown that the equivalent nets are not isomorphic.
The deposition of the amyloid β-protein (Aβ) is one of the pathological hallmarks of Alzheimer's disease (AD). Aβ-deposits show the morphology of senile plaques and cerebral amyloid angiopathy (CAA). Senile plaques and vascular Aβ-deposits occur first in neocorti-cal areas. Then, they expand hierarchically into further brain regions. The distribution of Aβ plaques throughout the entire brain, thereby correlates with the clinical status of the patients. Imaging techniques for Aβ make use of the hierarchical distribution of Aβ to distinguish AD patients from non-AD patients. However, pathology seen in AD patients represents a late stage of a pathological process starting 10–30 years earlier in cognitively normal individuals. In addition to the fibrillar amyloid of senile plaques, oligomeric and monomeric Aβ is found in the brain. Recent studies revealed that oligomeric Aβ is presumably the most toxic Aβ-aggregate, which interacts with glutamatergic synapses. In doing so, dendrites are presumed to be the primary target for Aβ-toxicity. In addition, vascular Aβ-deposits can lead to capillary occlusion and blood flow disturbances presumably contributing to the alteration of neurons in addition to the direct neurotoxic effects of Aβ. All these findings point to an important role of Aβ and its aggregates in the neurodegenerative process of AD. Since there is already significant neuron loss in AD patients, treatment strategies aimed at reducing the amyloid load will presumably not cure the symptoms of dementia but they may stop disease progression. Therefore, it seems to be necessary to protect the brain from Aβ-toxicity already in stages of the disease with minor neuron loss before the onset of cognitive symptoms.
Ribosome biogenesis in eukaryotes requires the participation of a large number of ribosome assembly factors. The highly conserved eukaryotic nucleolar protein Nep1 has an essential but unknown function in 18S rRNA processing and ribosome biogenesis. In Saccharomyces cerevisiae the malfunction of a temperature-sensitive Nep1 protein (nep1-1ts) was suppressed by the addition of S-adenosylmethionine (SAM). This suggests the participation of Nep1 in a methyltransferase reaction during ribosome biogenesis. In addition, yeast Nep1 binds to a 6-nt RNA-binding motif also found in 18S rRNA and facilitates the incorporation of ribosomal protein Rps19 during the formation of pre-ribosomes. Here, we present the X-ray structure of the Nep1 homolog from the archaebacterium Methanocaldococcus jannaschii in its free form (2.2 Å resolution) and bound to the S-adenosylmethionine analog S-adenosylhomocysteine (SAH, 2.15 Å resolution) and the antibiotic and general methyltransferase inhibitor sinefungin (2.25 Å resolution). The structure reveals a fold which is very similar to the conserved core fold of the SPOUT-class methyltransferases but contains a novel extension of this common core fold. SAH and sinefungin bind to Nep1 at a preformed binding site that is topologically equivalent to the cofactor-binding site in other SPOUT-class methyltransferases. Therefore, our structures together with previous genetic data suggest that Nep1 is a genuine rRNA methyltransferase.
Extracts of Boswellia serrata, also known as Indian frankincense, have been used to treat inflammatory diseases in the Indian ayurvedic medicine or Chinese traditional medicine (TCM) for over 3000 years, but the molecular mechanisms of the anti-inflammatory effects are still not well understood. It is obvious that the boswellic acids, the major compounds in the extracts, are responsible for the efficacy. This work employed a protein fishing technique to identify putative targets of boswellic acids at different stages within the inflammatory cascade. For fishing experiments, boswellic acids were immobilized to sepharose and incubated with cell lysates. After washing and boiling, fished proteins were separated by SDS-PAGE and analysed by MALDI-TOF-MS. CatG, DNA-PK and the protein kinase Akt were identified by protein pulldowns with immobilised BAs and characterised as selective and important targets for BAs with an IC50 in the range of physiologically achievable plasma levels up to 5 microM. In addition, the influence on several signal transductions by BAs was tested. Calcium influx, arachidonic acid release, platelet aggregation and TNFalpha-release were assayed to reveal further pharmacological effects of BAs. Celecoxib is a well-known selective COX-2 inhibitor that is in clinical use. In this work, it is demonstrated that celecoxib is also a highly potent direct 5-LO inhibitor. Celecoxib is used in arthritis and its gastro-intestinal side effects are reduced compared to non-selective NSAIDs. In patients with a familiar disposition to polyp forming, celecoxib reduced polyps and the incidence of colon cancer. Because of lowered leukotriene levels in patients under celecoxib therapy it was plausible to test whether celecoxib interferes with 5-LO. Here it is shown that the activity of 5-LO is inhibited in PMNL and cell-free assays with IC50 of 8 microM in intact cells, 20 microM with supplemented arachidonic acid and 30 microM in cell-free systems. Thus, celecoxib is a dual inhibitor of COX-2 and 5-LO. Since 2006, celecoxib has been approved as an orphan drug for the treatment of familial adenomatous polyposis. Aside from this indication, it could be useful for treatment of asthma and other diseases where 5-LO is implicated.
In the article, a travel sketch of Danish playwright Kaj Munk (1898 – 1944) is analytically considered. The analysis of this text allows drawing at least three conclusions: 1. Explicit motive of seasickness, figuring here as antithetic modification of implicite present free-standing posture motive, symbolizes idea of disintegrating personality. 2. Such a symbolism is deeply rooted in that of Danish identity. 3. From literary styles and trends history point of view, the sketch appears to be typical of that line in expressionism, which continues tradition of symbolism as artistic and literary trend of late 19th century.
The origin and justification of human rights, whether anchored in biological theory, natural law theory, or interests theory, as well as their cultural specificity and actual value as international legal instruments are subject to ongoing lively debates. As theoretical and rhetorical discourses challenge and enrich current understanding of the value of human rights and their relevance to democratic governance, they have found their way into public health in recent decades and play today an increasing role in the shaping of health policies, programs and practice. Human rights define the obligations of states to their people and towards each other, create grounds for governmental accountability and inspire recognition of, and action on, factors influencing people’s attainment of the highest possible standard of health. This article highlights the evolution that has brought health and human rights together in mutually reinforcing ways. It draws from the experience gained in the global response to HIV/AIDS, summarizes key dimensions of public health and of human rights and suggests a manner in which these dimensions intersect in a framework for analysis and action.
Our analysis of pseudopartitives and measure phrases draws on the idea of 'of' as a copula in a pseudopartitive. The copular analysis allows us to avoid the complications caused by treating either the numeral-noun combination before the of-phrase or the of-object as the head of a pseudopartitive on agreement, and hence to account for all the agreement patterns without creating any extra rule. We also outline how we can extend our analysis to handle measure phrases that do not co-occur with of-phrases by treating these measure phrases as anaphoric, an analysis that can adapt to the anaphoric constructions in classifier languages. Such an analysis does not only come closer to the intuition of native speakers but also have an appeal from the perspective of the universality of languages.
The correspondence between the terminology used for querying and the one used in content objects to be retrieved, is a crucial prerequisite for effective retrieval technology. However, as terminology is evolving over time, a growing gap opens up between older documents in (long-term) archives and the active language used for querying such archives. Thus, technologies for detecting and systematically handling terminology evolution are required to ensure "semantic" accessibility of (Web) archive content on the long run. As a starting point for dealing with terminology evolution this paper formalizes the problem and discusses issues, first ideas and relevant technologies.
In this paper, a methodology for the analysis of the structure of the thematic openings of academic journal articles is developed. The methodology is derived from Hyland (2000) and Fredrickson/Swales (1994). After sketching the methodology, it is used to examine a corpus of 14 articles selected from the periodical Beiträge zur Geschichte der deutschen Sprache und Literatur. The conclusion discusses perspective for further studies in this thematic field.
Before the turn of the millenium the investigation of phylogenetic relationships was revolutionized by two major inputs, the use of molecular sequence data for phylogenetic reconstruction, paralleled by the sophistication of computer aided reconstruction methods. The ever growing number of data however did not only result in clarifications of open questions, but brought forth a number of new conflicting phylogenetic hypotheses. Sometimes they are wrongly referred to as conflicts between morphological and molecular approaches, which sporadically even culminated in the rejection of the usefulness of one of the two approaches (e.g. Scotland et al 2003). These scientists overlook the great advantage of having two a priori largely independent data sets (Wägele 2001) which in a synthetic way enable the greatest progress in phylogenetic research. However, solely putting data together will not suffice to choose among conflicting hypotheses. The increasing number of conflicts necessitates approaches that go beyond mere data congruence, but searching for the possible reasons of conflicts. In the present paper, problems in the reconstruction of the phylogenetic origin of Hexapoda, as well as of the early branchings within the Hexapoda, will exemplify approaches of critical re-evaluation and testing of data used in morphological data matrices for phylogenetic analyses. The early cladogenetic events of hexapods are especially suited for such a discussion for several reasons. The hexapods, as the most species-rich group of organisms, look back at a long and multi-faceted history of taxonomic and phylogenetic studies, culminating in a number of conflicting hypotheses. Triggered by incongruences with morphological analyses the reconstruction of the hexapodan roots likewise became a hot-spot of molecular research activities during^the last two decades. Furthermore the phylogenetic positions of the oldest lineages branching off within the hexapodan clade, the Diplura, Protura and Collembola, are in particular very difficult to reconstruct. While at least the latter two are well defined by morphological autapomorphies their phylogenetic position could not be reconstructed unambiguously, since their morphology seems highly derived with respect to the hexapodan ground pattern.
We perform a detailed study of the adjoint static potential in the pseudoparticle approach, which is a model for SU(2) Yang-Mills theory. We find agreement with the Casimir scaling hypothesis and there is clear evidence for string breaking. At the same time the potential in the fundamental representation is linear for large separations. Our results are in qualitative agreement with results from lattice computations.
Ecological and biogeographical observations on Cerambycidae (Coleoptera) from California, USA
(2008)
New ecological and biogeographical observations are presented for the following 32 species of Cerambycidae from California: Atimia confusa dorsalis LeConte, Anelaphus albofasciatus (Linell), Aneflus prolixus prolixus LeConte, Anoplocurius incompletus Linsley, Brothylus conspersus LeConte, Callidiellum virescens Chemsak and Linsley, Calloides lorquini (Buquet), Clytus chemsaki Hovore and Giesbert, Enaphalodes hispicornis (Linnaeus), Methia brevis Fall, Neaneflus fuchsi (Wickham), Neoclytus balteatus LeConte, Plectromerus dentipes (Olivier), Phymatodes decussatus decussatus (LeConte), Phymatodes decussatus australis Chemsak, Purpuricenus dimidiatus LeConte, Rosalia funebris Motschulsky, Schizax senex LeConte, Smodicum pacificum Linsley, Stenaspis solitaria (Say), Tragidion gracilipes Linsley, Brachysomida californica (LeConte), Brachysomida vittigera Linsley and Chemsak, Centrodera osburni Knull, Encyclops californica Van Dyke, Judolia sexspilota (LeConte), Leptalia macilenta (Mannerheim), Leptura hovorei Linsley and Chemsak, Leptura pacifica (Linsley), Necydalis barbarae Rivers, Neobellamira delicata australis Linsley and Chemsak, Pachyta armata LeConte, Stenocorus alteni Giesbert and Hovore.
Electron tomography was used to investigate membrane proteins in a variety of contexts. A high-angle tilt holder, suitable for electron tomography was designed, constructed and characterised. 2D crystals of membrane proteins, NhaA and YidC, were examined as a resolution test, and a method established for determining planarity of crystals. A model for specific gold binding to NhaA crystals was also presented. ATP synthase, a membrane protein complex in mitochondria, were imaged in a frozen hydrated state. They were found to form ribbons of dimers at highly curved regions of the membrane. Dimers from bovine heart and rat liver were excised from the tomographic volumes and averaged. Based on the location of the dimers in the mitochondrion, a model was established whereby ATP synthase, a molecular motor driven by the proton motive force, benefits from the high curvature that it induces in the membrane. Whole yeast mitochondria, imaged by electron cryo-tomography, also contained long ribbons of dimeric ATP synthase. Multiple copies of an unknown membrane protein complex were visualised by electron cryo-tomography, excised and averaged. A general method for the identification of unknown proteins was presented to deal with this inevitable issue, as native tissues and organelles are imaged, and the structures of complexes determined in situ.
5-LO is the key enzyme in the biosynthesis of proinflammatory leukotrienes. It catalyses the conversion of arachidonic acid to the hydroperoxy intermediate 5(S)-hydroperoxy-6- trans-8,11,14-cis-eicosatetraenoic acid (5-HpETE). In a second step 5-LO catalyses a dehydration reaction forming the unstable epoxide intermediate 5(S)-trans-5,6-oxido-7,9- trans-11,14-cis-eicosatetraenoic acid (leukotriene A4 , LTA4). The 5-LO gene is subjected to versatile regulation mechanisms. Apart from regulation by DNA-methylation and histone acetylation / deacetylation 5-LO gene expression can be regulated by the differentiation inducers calcitriol (1,25-dihydroxyvitamin D3) and transforming growth factor beta (TGFβ) 5-LO gene expression. In the myeloid cell lines Mono Mac 6 (MM6) and HL-60, differentiation with both agents caused a prominent upregulation of 5-LO mRNA level, of 5-LO protein expression and of 5-LO activity. Treatment with calcitriol alone already has an impact on 5-LO gene expression which is additionally potentiated by TGFβ treatment. Previous nuclear run-off analysis and reporter gene analysis could not associate the 5-LO promoter with the induction of 5-LO mRNA expression mediated by calcitriol and TGFβ. Inclusion of the 5-LO coding sequence (cds) and inclusion of the 5-LO cds plus the last four introns of the gene (J to M) in the 5-LO promoter construct pN10 led to an enhanced reporter gene activity. The inductions were dependent on vitamin D receptor (VDR) and retinoid x receptor (RXR) cotransfection. Therefore the work was concentrated on identifying elements outside the 5-LO promoter region which contribute to the calcitriol / TGFβ effect on 5-LO mRNA expression. Insertion of the LTA4 hydrolase coding sequence – a coding sequence of similar size - instead of the 5-LO cds led to a loss of the calcitriol / TGFβ effect (pN10LTA4Hcds 1-fold induction). Therewith, it was proven that the presence of the 5-LO cds is crucial for the upregulating effect of calcitriol / TGFβ on 5-LO mRNA level. Cloning of the SV40 promoter instead of pN10 upstream of the 5-LO cds still showed inducibility by treatment with the inducers which argues for a promoter unspecific effect. Insertion of the 5-LO cds in a promoterless basic vector (pGL3cds) displayed same inductions by calcitriol / TGFβ treatment as the 5-LO promoter 5-LO cds construct (pN10cds). Thus, the effect of the inducers is not dependent on the 5-LO promoter under the in vitro conditions of the reporter gene assay. Hence, further cloning was done with promoterless constructs. Through 5-LO cds deletion constructs a positive regulating region in exon 10 to 14 was discovered. To adapt the natural gene context the last four introns (J-M) of the 5-LO gene were inserted in a promoterless construct containing exon 10 to 14 (pGL3cdsΔABInJM). 5end deletion constructs of it revealed putative vitamin D responsive elements (VDREs) in exon 12 and intron M. Mutation of the putative VDREs led to a reduced calcitriol effect –more prominent when the putative VDRE in intron M was mutated (reduction of 40%). Moreover another putative VDRE in exon 10 with an adjacent SMAD binding element (SBE) was detected. SMAD proteins are effector proteins of TGFβ signalling. Gelshift experiments demonstrated in vitro binding of the VDR-RXR heterodimer to those three putative VDREs. By chromatin immunoprecipitation (ChIP) assay in vivo binding of VDR and RXR was shown to the VDRE in the region of exon 10, exon 12 and intron M. 8h and 24h incubation with calcitriol / TGFβ resulted in enhanced expression of VDR in each of the examined regions. The VDR is able to bind to the VDRE without its ligand, whereas this goes along with corepressor recruitment and thus the VDR has a repressive effect on transcription. Histone H4 acetylation was increased when MM6 cells were treated for 8h or 24h with calcitriol or the combination of calcitriol / TGFβ. This finding implies that at that point of time corepressors associated with the VDR are replaced by coactivators. It seems convincing that 5-LO transcription is mainly promoted by calcitriol alone which leads to a more accessible chromatin structure. Previous data indicated that calcitriol and TGFβ upregulate 5-LO RNA maturation and 5- LO transcript elongation. Thus several elongation markers were investigated by ChIP analysis: Histone H3 lysine 36 (H3K36) trimethylation and H4K20 monomethylation were detected in the analysed regions in exon 10, exon 12 and intron M. In region exon 10 the H3K36 trimethylation status was enhanced after 24h calcitriol or calcitriol / TGFβ treatment. An increased H4K20 monomethylation status in all regions was observed when MM6 cells were treated for 24h with calcitriol / TGFβ. 24h treatment with both agents also enhanced the recruitment of the elongation form of RNA polymerase II, which is phosphorylated at serine 2 of the carboxyterminal domain, to the investigated regions. These findings prove the positive regulating role for calcitriol and TGFβ on 5-LO transcript elongation. A putative mechanism of the effect of calcitriol and TGFβ on 5-LO RNA maturation might be the elevated phosphorylation of serine 2 of the RNA Polymerase II which is known to be followed by recruiting polyadenylating factors.
Global distributions of profiles of sulphur hexafluoride (SF6) have been retrieved from limb emission spectra recorded by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) on Envisat covering the period September 2002 to March 2004. Individual SF6 profiles have a precision of 0.5 pptv below 25 km altitude and a vertical resolution of 4–6 km up to 35 km altitude. These data have been validated versus in situ observations obtained during balloon flights of a cryogenic whole-air sampler. For the tropical troposphere a trend of 0.230±0.008 pptv/yr has been derived from the MIPAS data, which is in excellent agreement with the trend from ground-based flask and in situ measurements from the National Oceanic and Atmospheric Administration Earth System Research Laboratory, Global Monitoring Division. For the data set currently available, based on at least three days of data per month, monthly 5° latitude mean values have a 1 o standard error of 1%. From the global SF6 distributions, global daily and monthly distributions of the apparent mean age of air are inferred by application of the tropical tropospheric trend derived from MIPAS data. The inferred mean ages are provided for the full globe up to 90° N/S, and have a 1 o standard error of 0.25 yr. They range between 0 (near the tropical tropopause) and 7 years (except for situations of mesospheric intrusions) and agree well with earlier observations. The seasonal variation of the mean age of stratospheric air indicates episodes of severe intrusion of mesospheric air during each Northern and Southern polar winter observed, long-lasting remnants of old, subsided polar winter air over the spring and summer poles, and a rather short period of mixing with midlatitude air and/or upward transport during fall in October/November (NH) and April/May (SH), respectively, with small latitudinal gradients, immediately before the new polar vortex starts to form. The mean age distributions further confirm that SF6 is destroyed in the mesosphere to a considerable degree. Model calculations with the Karlsruhe simulation model of the middle atmosphere (KASIMA) chemical transport model agree well with observed global distributions of the mean age only if the SF6 sink reactions in the mesosphere are included in the model.
Poster presentation: Purpose of the study The aim of the Rainbow Cohort is to assess the tolerability and efficacy of initiating treatment with, or switching treatment to the saquinavir (SQV) 500 mg film-coated tablet formulation. We present the final 48-week subgroup analysis of PI-experienced, but SQV-naïve patients. ...
We consider two alternatives for memory management in typed-feature-structure-based parsers by identifying structural properties of grammar signatures that may be of some predictive value in determining the consequences of those alternatives. We define these properties, summarize the results of a number of experiments on artificially constructed signatures with respect to the relative rank of their asymptotic cost at parse-time, and experimentally consider how they impact memory management.
Bromotriphenylsilane
(2008)
The title compound, C18H15BrSi, crystallizes with two almost identical molecules (r.m.s. deviation for all non-H atoms = 0.074 Å) in the asymmetric unit. It is isomorphous with chlorotriphenylsilane. Key indicators: single-crystal X-ray study; T = 173 K; mean σ(C–C) = 0.010 Å; R factor = 0.095; wR factor = 0.288; data-to-parameter ratio = 17.0.
Given the simplicity of the method and how it can be applied, as well as proof that it lowers the mortality rate, fecal occult blood testing (FOBT) is currently the most commonly used screening method for colorectal cancer (CRC). However, the test suffers from poor sensitivity, particularly with respect to detecting early stages, as well as low acceptance among the population. Preliminary data on detecting calprotectin and tumour-M2-PK in the stool indicated that a better screening performance could be expected. But these tests also suffer from low sensitivity in detecting early stages and from poor specificity, thus limiting the usefulness of the tests as a result of high follow-up costs. Recently developed immunological tests (I-FOBT) demonstrate significantly increased sensitivity and specificity. I-FOBTs use antibodies specific to human hemoglobin and are therefore not affected by diet and drugs, leading to improved patient partipication. At present, I-FOBTs seem to be the most cost-effective approach for non-invasive screening. The detection of tumour-DNA in the stool opens up a new era in early diagnosis of colorectal cancer. Small trials have pointed to a very high sensitivity of these methods: 62–91% for colorectal cancer and between 26% and 73% for adenomas, with a very high level of specificity (93–100%). The major drawback of this type of testing, compared with other screening tests available today, is its high cost.