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In many cases, the dire situation of public finances calls into question the very soundness of sovereigns and prompts corrective actions with far-reaching consequences. In this context, European authorities responded with several measures on different fronts, for instance by passing the "Fiscal Compact", which entered into force on January 1, 2013. Of critical importance in this framework is the assessment of a country’s situation by way of statistical measures, in order to take corrective actions when called for according to the letter of the law. If these statistics are not correct, there is a risk of imposing draconian measures on countries that do not really need it.
The implications of delegating fiscal decision making power to sub-national governments has become an area of significant interest over the past two decades, in the expectation that these reforms will lead to better and more efficient provision of public goods and services. The move towards decentralization has, however, not been homogeneously implemented on the revenue and expenditure side: decentralization has materialized more substantially on the latter than on the former, creating "vertical fiscal imbalances". These imbalances measure the extent to which sub-national governments’ expenditures are financed through their own revenues. This mismatch between own revenues and expenditures may have negative consequences for public finances performance, for example by softening the budget constraint of sub-national governments. Using a large sample of countries covering a long time period from the IMF’s Government Finance Statistics Yearbook, this paper is the first to examine the effects of vertical fiscal imbalances on fiscal performance through the accumulation of government debt. Our findings suggest that vertical fiscal imbalances are indeed relevant in explaining government debt accumulation, and call for a degree of caution when promoting fiscal decentralization.
We show that the correct experiment to evaluate the effects of a fiscal adjustment is the simulation of a multi year fiscal plan rather than of individual fiscal shocks. Simulation of fiscal plans adopted by 16 OECD countries over a 30-year period supports the hypothesis that the effects of consolidations depend on their design. Fiscal adjustments based upon spending cuts are much less costly, in terms of output losses, than tax-based ones and have especially low output costs when they consist of permanent rather than stop and go changes in taxes and spending. The difference between tax-based and spending-based adjustments appears not to be explained by accompanying policies, including monetary policy. It is mainly due to the different response of business confidence and private investment.
We develop a methodology to identify and rank “systemically important financial institutions” (SIFIs). Our approach is consistent with that followed by the Financial Stability Board (FSB) but, unlike the latter, it is free of judgment and it is based entirely on publicly available data, thus filling the gap between the official views of the regulator and those that market participants can form with their own information set. We apply the methodology to annual data on three samples of banks (global, EU and euro area) for the years 2007-2012. We examine the evolution of the SIFIs over time and document the shifs in the relative weights of the major geographic areas. We also discuss the implication of the 2013 update of the identification methodology proposed by the FSB.
pH and Na+ homeostasis in all cells requires Na+/H+ antiporters. The crystal structure, obtained at pH 4, of NhaA, the main antiporter of Escherichia coli, has provided general insights into an antiporter mechanism and its unique pH regulation. Here, we describe a general method to select various NhaA mutants from a library of randomly mutagenized NhaA. The selected mutants, A167P and F267C are described in detail. Both mutants are expressed in Escherichia coli EP432 cells at 70–95% of the wild type but grow on selective medium only at neutral pH, A167P on Li+ (0.1 M) and F267C on Na+ (0.6 M). Surprising for an electrogenic secondary transporter, and opposed to wild type NhaA, the rates of A167P and F267C are almost indifferent to membrane potential. Detailed kinetic analysis reveals that in both mutants the rate limiting step of the cation exchange cycle is changed from an electrogenic to an electroneutral reaction.
The Late Cretaceous is known to be mostly affected by warm periods interrupted temporarily by a number of cooling events. The reconstruction of the paleoclimatic conditions during a period of high concentration of CO2 in the atmosphere is of great importance for the creation of future climate models. We applied the recently developed method reconstructing the SST from the TEX86 (TetraEther indeX of tetraethers consisting of 86 carbon atoms).
The sample material used for the present study was obtained from the tropical Late Cretaceous southern Tethys upwelling system (Negev/Israel), lasting from the Late Santonian to the Early Maastrichtian (~ 85 to 68 Ma). On the core samples from the Shefela basin, representing the outer belt of the upwelling system and the outcrop profile from the open mine Mishor Rotem (Efe Syncline), representing the inner belt, various bulk geochemical and biomarker studies were performed in this thesis.
Derived from TEX86 data, a significant long-term SST cooling trend from 36.0 to 29.3 °C is recognized during the Late Santonian and the Early Campanian in the southern Tethys margin. This is consistent with the opening and deepening of the Equatorial Atlantic Gateway (EAG) and the intrusion of cooler deep water from the southern Atlantic Ocean influencing the global SSTs and also the Tethys Ocean. Furthermore, the cooler near shore SST usually found in modern upwelling systems could be verified in case of the ancient upwelling system investigated in the present study. The calculated mean SST in the inner belt (27.7 °C) represented in the Efe Syncline was 1.5 °C cooler in comparison to the more seaward located outer belt (Shefela basin).
Moreover, geochemical and biomarker analyses were used to identify both the accumulation of high amounts of phosphate in the PM and good preservation of organic matter (OM) in the lower part of the OSM section. Total organic carbon (TOC) contents are highly variable over the whole profile reaching from 0.6 % in the MM, to 24.5 % in the OSM. Total iron (TFe) varies from 0.1 % in the PM to 3.3 % in the OSM and total sulfur (TS) varies between 0.1 % in the MM and 3.4 % in the OSM. Different correlations of TS, TOC and TFe were used to identify the conditions during the deposition of the different facies types. Natural sulfurization was found to play a key role in the preservation of the OM particularly in the lower part of the OSM. Samples from the OSM and the PM were deposited under dysoxic to anoxic conditions and iron limitation lasted during the deposition of the OSM and the PM, which effected the incorporation of sulfur into OM.
Phosphorus is highly accumulated in the sediments of the PM with a mean proportion of 11.5 % total phosphorus (TP), which is drastically reduced to a mean value of 0.9 % in the OSM and the MM. From the correlation of the bulk geochemical parameters TOC/TOCOR ratio and TP a major contribution of sulfate reducing bacteria to the phosphate deposition is concluded. This interrelation has previously been investigated in recent coastal upwelling systems off Peru, Chile, California and Namibia. This was further supported by the analysis of branched and monounsaturated fatty acids indicating the occurrence of sulfate reducing and sulfide oxidizing bacteria during the deposition.
According to the results from the analysis of n-alkanes and C27- to C29-steranes up to 95 % of the OM was of marine origin.
Organic sulfur compounds (OSC) were a major compound class in the aromatic hydrocarbon fraction and n-Alkyl and isoprenoid thiophenes were the most abundant, with highest amounts found for 2-methyl-5-tridecyl-thiophene (28 µg/g TOC). The relatively high abundance of ββ-C35 hopanoid thiophenes and epithiosteranes is equivalent to an incorporation of sulfur during the early stages of diagenesis.
Moreover, the geochemical parameters δ13Corg, δ15Norg, C/N and the pristane/phytane (Pr/Ph) ratio, were studied for reconstruction of seafloor and water column depositional environments. The high C/N ratio along with relatively low values of δ15Norg (4 ‰ to 6 ‰) and δ13Corg (-29 ‰ to -28 ‰) are consistent with a significant preferential loss of nitrogen-rich organic compounds during diagenesis. Oxygen-depleted conditions lasted during the deposition of the PM and the bottom of the OSM, reflected by the low Pr/Ph ratio of 0.11–0.7. In the upper part of the OSM and the MM the conditions changed from anoxic to dysoxic or oxic conditions. This environmental trend is consistent with co-occurring foraminiferal assemblages in the studied succession and implies that the benthic species in the Negev sequence were adapted to persistent minimum oxygen conditions by performing complete denitrification as recently found in many modern benthic foraminifera.
Furthermore, the anammox process could have influenced the nitrogen composition of the sediments. In this anaerobically process nitrite and ammonia are converted to molecular nitrogen.
Xylotrechus rameyi, new species, (Coleoptera: Cerambycidae) is described from southern Utah. Comments on its biology including habitat, host plants and larval history are provided along with photographs of the holotype, allotype, the related species X. insignis LeConte, and the larval galleries and pupal chamber.
Fluctuations of the water level at the edges of temporary water bodies provide favourable living conditions for annual plant communities of the phytosociological class Isoëto-Nanojuncetea. Such communities of periodically flooded ponds within the agricultural landscape of NE Germany are particularly rich in rare plant species of that class. During the past decades drainage, fertilisation and herbicides in the surrounding arable fields have led to a severe decline in diversity of these species. To develop efficient conservation strategies it is essential to understand the factors driving the species composition. Therefore, we studied how varying water regimes, soil properties and agricultural practices affect the diversity and species composition of these temporary ponds. The study was carried out in seven ponds on a conventionally managed farm in NE Brandenburg. At each of these wetlands mixed soil samples were taken to determine the pH, total nitrogen and phosphorus concentration. The plant species were recorded in 177 plots, each covering 1 x 1 m2. For each plot, the water level was recorded in April, July and August 2013, respectively, resulting in five "water level regimes". Total species number and percentages of Isoëto-Nanojuncetea species were determined per plot, to evaluate water level effects on the vegetation. In addition, mean Ellenberg indicator values for light, moisture and nutrients were calculated to assess the environmental conditions.
The subject of this thesis is the experimental investigation of the neutron-capture cross sections of the neutron-rich, short-lived boron isotopes 13B and 14B, as they are thought to influence the rapid neutron-capture process (r process) nucleosynthesis in a neutrino-driven wind scenario.
The 13;14B(n,g)14;15B reactions were studied in inverse kinematics via Coulomb dissociation at the LAND/R3B setup (Reactions with Relativistic Radioactive Beams). A radioactive beam of 14;15B was produced via in-flight fragmentation and directed onto a lead-target at about 500 AMeV. The neutron breakup of the projectile within the electromagnetic field of the target nucleus was investigated in a kinematically complete measurement. All outgoing reaction products were detected and analyzed in order to reconstruct the excitation energy.
The differential Coulomb dissociation cross sections as a function of the excitation energy were obtained and first experimental constraints on the photoabsorption and the neutron-capture cross sections were deduced. The results were compared to theoretical approximations of the cross sections in question. The Coulomb dissociation cross section of 15B into 14B(g.s.) + n was determined to be s(15B;14B(g:s:)+n) CD = 81(8stat)(10syst) mb ; while the Coulomb dissociation cross section of 14B into a neutron and 13B in its ground state was found to be s(14B;13B(g:s:)+n) CD = 281(25stat)(43syst) mb: Furthermore, new information on the nuclear structure of 14B were achieved, as the spectral shape of the differential Coulomb dissociation cross section indicates a halolike structure of the nucleus.
Additionally, the Coulomb dissociation of 11Be was investigated and compared to previous measurements in order to verify the present analysis. The corresponding Coulomb dissociation cross section of 11Be into 10Be(g.s.) + n was found to be 450(40stat)(54syst ) mb, which is in good agreement with the results of Palit et al.
During an entomological survey in Santiago Island, Cape Verde Islands, in November-December 2011 in order to study the bio-ecology and susceptibility to insecticides of Anopheles arabiensis Patton, 1905, Culex tritaeniorhynchus Giles, 1901 was found to be present in the Santa Cruz District. Both adult and immature specimens were collected and a description of both is given. Further confirmation of the taxonomic identity of the specimens was obtained from studying the male genitalia. This is the first known occurrence of Culex tritaeniorhynchus (a primary vector of Japanese encephalitis in eastern and southern Asia and a potential vector of West Nile Virus, Sindbis and Rift Valley Fever Virus) in the Cape Verde Islands.
We compared Chatham Island endemic species Xanthocnemis tuanuii to its congenerics from the New Zealand South Island: X. zealandica (newly collected specimens)and X. sinclairi (type specimens plus newly collected material). Two independent tests were performed –geometric morphometrics and molecular. Both analyses were consistent in supporting the status of X. tuanuiias a good species. Species differed statistically in the following morphological traits: head (dorsal view), male appendages (dorsal, lateral, posterior and ventral views), thorax (dorsal view), and penis (dorsal and lateral view). In addition to the original diagnostic features (mainly shape of the male superior appendages), a new morphological character is suggested here which reliably distinguishes the species based on the shape of the inferior appendages. There was no statistical support for the species status of X. sinclairi. The only feature re-ported as diagnostic (lower lobe of male superior appendages) was found to be variable and insufficient to warrant the previously proposed taxonomic rank for X. sinclairi. Molecular analysis of specimens showing identical appendages to the X. sinclairi holotype grouped them with X. zealandica specimens. Therefore X. sinclairi is synonymised with X. zealandica.
It has become increasingly apparent over the last decades that cooking pottery played a considerable role as a trade commodity in ancient times, yet relatively little research has yet been done on this topic for its own sake. By taking a closer look at the cooking pottery found in Priene, a small city in southern Ionia re-founded in the middle of the 4th century BCE, we want to trace some of the broader developments within the cooking wares that were used over a period of roughly 300 years. The aim is not only to outline the general shapes that were in use over this period of time, but also to register if and how these shapes correlate with the different fabrics observed in Priene so far.
OBJECTIVES: Outcome of aortic valve replacement may be influenced by the choice of bioprosthesis. Pericardial heart valves are described to have a favourable haemodynamic profile compared with porcine valves, although the clinical notability of this finding is still controversially debated. Herein, we compared the long-term results of two commonly implanted bioprosthesis at a single centre.
METHODS: All consecutive patients undergoing isolated aortic valve replacement with either a Carpentier-Edwards Magna pericardial prosthesis or a Medtronic Mosaic porcine prosthesis between 2002 and 2008 were analysed regarding preoperative characteristics, short- and long-term survival, valve-related complications and echocardiographic findings.
RESULTS: The Medtronic Mosaic was implanted in 163 patients and the Carpentier-Edwards Magna in 295 patients. The sizes of implanted valves were 22.4 ± 1.5 mm for the Mosaic and 21.8 ± 1.8 mm for the Magna (P = 0.001). The long-term survival rate was 76 and 56% after 5 and 10 years for the Medtronic Mosaic, which was comparable with the Carpentier-Edwards Magna (77 and 57%; P = 0.92). Overall long-term survival was comparable with an age- and sex-matched Austrian general population for both groups. Valve-related adverse events were similar between groups. The postoperative mean transvalvular gradient was significantly increased in the Mosaic group (24 ± 9 mmHg vs 17 ± 7 mmHg; P < 0.001).
CONCLUSIONS: Both types of aortic bioprostheses offer excellent results after isolated aortic valve replacement. Despite relevant differences in gradients, long-term survival was comparable with the expected normal survival for both bioprostheses. Patients with a porcine heart valve had a higher postoperative transvalvular gradient.
In this concise volume, author and legal scholar Michael Stolleis provides an overview of the development of the modern German welfare state. Stolleis’ analysis focuses on labor law and social policy, while acknowledging the influence of economic, social, and cultural factors thereon. Origins of the German Welfare State does not emphasize a complete understanding of its subject; rather it seeks to provide insight into the development of German social policy in relation to the political/ historical eras in which it finds itself, leading to a deeper understanding of the foundations of social policy. ...
Exit strategies
(2014)
We study alternative scenarios for exiting the post-crisis fiscal and monetary accommodation using a macromodel where banks choose their capital structure and are subject to runs. Under a Taylor rule, the post-crisis interest rate hits the zero lower bound (ZLB) and remains there for several years. In that condition, pre-announced and fast fiscal consolidations dominate - based on output and inflation performance and bank stability - alternative strategies incorporating various degrees of gradualism and surprise. We also examine an alternative monetary strategy in which the interest rate does not reach the ZLB; the benefits from fiscal consolidation persist, but are more nuanced.
Cameroon's Predicaments
(2014)
This book deals with a variety of socio-cultural, economic and political problems facing Cameroon and the rest of Africa, with particular reference to unemployment, corruption, poverty, criminality, violence, insecurity, and moral decadence. It presents a critical analysis of government policies from the colonial era to the present time; arguing that most of these policies have been stalled by an uncommitted leadership. The regime in Cameroon has drifted away from basic managerial and democratic principles in in favour of the ethnicisation of politics, sterile consumption, clientelism and patronage. The book contends that corruption has become the main instrument of governance whereby the political and economic elites control the wealth of the nation at the expense of a majority who wallow in abject poverty and misery. Faced with the difficult economic and political situation, most youth and the intelligentsia have adopted ?official and ?unofficial? means to circumvent all immigration rules to travel to affluent Western countries, the consequences notwithstanding. Brain drain is often the outcome. Further, it examines issues of social exclusion, political representation and marginalization with special focus on the predicament of Anglophone Cameroonians as a socio-cultural community. The inclusion of examples and case studies based on empirical and secondary data from Africa is intended to foreground the importance of comparison, and attract the interest of both academic and non-academic readership.
Blood Lines and other Plays
(2014)
Chris Anyokwu's new creative offerings are snapshots of a the quotidian reality in the playwrights homeland, Nigeria, where polygamy and its associated evils, crass materialism and its classless followers still predominate. Even the ivory towers are not left out as petty rivalry, dirty politics and even fetishism seem to be the name of the game.
We examine the impact of so-called "Crisis Contracts" on bank managers' risk-taking incentives and on the probability of banking crises. Under a Crisis Contract, managers are required to contribute a pre-specified share of their past earnings to finance public rescue funds when a crisis occurs. This can be viewed as a retroactive tax that is levied only when a crisis occurs and that leads to a form of collective liability for bank managers. We develop a game-theoretic model of a banking sector whose shareholders have limited liability, so that society at large will suffer losses if a crisis occurs. Without Crisis Contracts, the managers' and shareholders' interests are aligned, and managers take more than the socially optimal level of risk. We investigate how the introduction of Crisis Contracts changes the equilibrium level of risk-taking and the remuneration of bank managers. We establish conditions under which the introduction of Crisis Contracts will reduce the probability of a banking crisis and improve social welfare. We explore how Crisis Contracts and capital requirements can supplement each other and we show that the efficacy of Crisis Contracts is not undermined by attempts to hedge.
Dendritic cells (DCs) are the cutting edge in innate and adaptive immunity. The major functions of these antigen-presenting cells are the capture, endosomal processing and presentation of antigens, providing them an exclusive ability to provoke adaptive immune responses and to induce and control tolerance. Immature DCs capture and process antigens, migrate towards secondary lymphoid organs where they present antigens to naive T cells in a well-synchronized sequence of procedures referred to as maturation. Indeed, recent research indicated that sphingolipids are modulators of essential steps in DC homeostasis. It has been recognized that sphingolipids not only modulate the development of DC subtypes from precursor cells but also influence functional activities of DCs such as antigen capture, and cytokine profiling. Thus, it is not astonishing that sphingolipids and sphingolipid metabolism play a substantial role in inflammatory diseases that are modulated by DCs. Here we highlight the function of sphingosine 1-phosphate (S1P) on DC homeostasis and the role of S1P and S1P metabolism in inflammatory diseases.
Cognitive flexibility and cognitive stability : neural and behavioral correlates in men and mice
(2014)
The ability to flexibly adjust behavior according to a changing environment is crucial to ensure a species' survival. However, the successful pursuit of goals also requires the stable maintenance of behavior in the face of potential distractors. Thus, cognitive flexibility and cognitive stability are important processes for the cognitive control of behavior. There is a large body of behavioral and neuroimaging research concerning cognitive control in general, but also specifically on cognitive flexibility and cognitive stability, albeit most often assessed in separate task paradigms. Nevertheless, whether cognitive flexibility and cognitive stability depend upon separate or shared neuronal bases is still a matter of debate. Complementing empirical research, computational models have become an important strategy in neuroscientific research, as they have the potential of providing mechanistic explanations of empirical observations, for example by allowing for the direct manipulation of molecular parameters in simulated neural networks. The computational model underlying the so-called Dual-State Theory contains specific hypotheses with respect to cognitive flexibility and cognitive stability. The neural networks simulated by this model exhibit multiple stable firing states, i.e., the neural network can maintain a high firing state also without continuing external input due to a network architecture consisting of recurrently connected neurons. Transitions between such network states, also called attractor states, can be induced by external input, and represent working memory contents or active task rules. Simulations showed that the stability of these attractor states, and thus of task rule representations, depend on the dopamine state of the system and can consequently vary between persons. The Dual-State Theory predicts an antagonistic relationship between cognitive flexibility and cognitive stability, as robust attractor states would facilitate the inhibition of distractors, but impair efficient task switching, while rather unstable attractor states would promote efficient transitions between representations but would also come at the cost of increased distractibility.
Based on the Dual-State Theory, a task paradigm was designed allowing for the simultaneous assessment of cognitive flexibility, in the sense of rule-based task switching, and cognitive stability, in the sense of inhibiting irrelevant distractors. Furthermore, a behavioral measure was developed to assess the individual attractor state stability, named spontaneous switching rate (SSR). In the first study of this work, this paradigm was tested in a sample of healthy human subjects using functional magnetic resonance imaging (fMRI). An overlapping fronto-parietal network was activated for both cognitive flexibility and cognitive stability. Furthermore, behavioral as well as neuroimaging results are in favor of an antagonistic relationship between cognitive flexibility and cognitive stability. A specific prefrontal region, the inferior frontal junction (IFJ), was implied to potentially contain the relevant neural networks mediating the transitions between attractor states, i.e., task rule representations, as its activity was modulated by the SSR such that persons with rather unstable attractor states activated it less during task switching while showing better performance. Most importantly, functional connectivity of the IFJ was antagonistically modulated by the SSR: more flexible persons connected it less to another prefrontal area during task switching, while showing higher functional connectivity during distractor inhibition.
In a second study, a larger human sample was assessed and further hypotheses derived from the Dual-State Theory on variability of neural processing were tested: we hypothesized that persons with high brain signal variability should have less stable network states and thus benefit on tasks requiring cognitive flexibility but suffer from it when the task requires a higher degree of cognitive stability. Furthermore, recent fMRI-research on brain signal variability revealed beneficial effects of higher brain signal variability on cognitive performance in general. Using a novel customized analysis pipeline to measure trial-to-trial fMRI-signal variability, we indeed found differential effects of brain signal variability: higher levels of brain signal variability were found to be beneficial for effectiveness, i.e., performance in terms of error rates, for both cognitive flexibility and stability. However, brain signal variability impaired the efficiency in terms of response times of inhibiting distractors, i.e., cognitive stability.
Due to further predictions of the Dual-State Theory concerning schizophrenia and the dopaminergic system, it was considered valuable to pursue a translational approach and thus allowing for the employment of animal models of psychiatric diseases. Consequently, in a first step the human paradigm was translated for a murine population using an innovative touchscreen approach. Results showed analogous behavioral effects in wildtype mice as before in healthy humans: the antagonistic relation between cognitive flexibility and cognitive stability was replicated and also for mice, a behavioral measure for the individual attractor stability was established and validated, named the individual spontaneous switching score.
To conclude, we established a novel paradigm assessing both cognitive flexibility and stability simultaneously showing an antagonistic relationship between these two cognitive functions on the behavioral level in two different species, which supports predictions from the Dual-State Theory. This was further underlined by evidence on the activation, functional connectivity and signal variability level in the human brain.