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Virus-infected cells are eliminated by cytotoxic T lymphocytes, which recognize viral epitopes displayed on major histocompatibility complex class I molecules at the cell surface. Herpesviruses have evolved sophisticated strategies to escape this immune surveillance. During the lytic phase of EBV infection, the viral factor BNLF2a interferes with antigen processing by preventing peptide loading of major histocompatibility complex class I molecules. Here we reveal details of the inhibition mechanism of this EBV protein. We demonstrate that BNLF2a acts as a tail-anchored protein, exploiting the mammalian Asna-1/WRB (Get3/Get1) machinery for posttranslational insertion into the endoplasmic reticulum membrane, where it subsequently blocks antigen translocation by the transporter associated with antigen processing (TAP). BNLF2a binds directly to the core TAP complex arresting the ATP-binding cassette transporter in a transport-incompetent conformation. The inhibition mechanism of EBV BNLF2a is distinct and mutually exclusive of other viral TAP inhibitors.
The E3 ubiquitin ligase MYCBP2 negatively regulates neuronal growth, synaptogenesis, and synaptic strength. More recently it was shown that MYCBP2 is also involved in receptor and ion channel internalization. We found that mice with a MYCBP2-deficiency in peripheral sensory neurons show prolonged thermal hyperalgesia. Loss of MYCBP2 constitutively activated p38 MAPK and increased expression of several proteins involved in receptor trafficking. Surprisingly, loss of MYCBP2 inhibited internalization of transient receptor potential vanilloid receptor 1 (TRPV1) and prevented desensitization of capsaicin-induced calcium increases. Lack of desensitization, TRPV internalization and prolonged hyperalgesia were reversed by inhibition of p38 MAPK. The effects were TRPV-specific, since neither mustard oil-induced desensitization nor behavioral responses to mechanical stimuli were affected. In summary, we show here for the first time that p38 MAPK activation can inhibit activity-induced ion channel internalization and that MYCBP2 regulates internalization of TRPV1 in peripheral sensory neurons as well as duration of thermal hyperalgesia through p38 MAPK.
Host cell invasion by the facultative intracellular pathogen Listeria monocytogenes requires the invasion protein InlB in many cell types. InlB consists of an N-terminal internalin domain that binds the host cell receptor tyrosine kinase Met and C-terminal GW domains that bind to glycosaminoglycans (GAGs). Met binding and activation is required for host cell invasion, while the interaction between GW domains and GAGs enhances this effect. Soluble InlB elicits the same cellular phenotypes as the natural Met ligand hepatocyte growth factor/scatter factor (HGF/SF), e.g. cell scatter. So far, little is known about the central part of InlB, the B-repeat. Here we present a structural and functional characterization of the InlB B-repeat. The crystal structure reveals a variation of the β-grasp fold that is most similar to small ubiquitin-like modifiers (SUMOs). However, structural similarity also suggests a potential evolutionary relation to bacterial mucin-binding proteins. The B-repeat defines the prototype structure of a hitherto uncharacterized domain present in over a thousand bacterial proteins. Generally, this domain probably acts as a spacer or a receptor-binding domain in extracellular multi-domain proteins. In cellular assays the B-repeat acts synergistically with the internalin domain conferring to it the ability to stimulate cell motility. Thus, the B-repeat probably binds a further host cell receptor and thereby enhances signaling downstream of Met.
This paper compares the shareholder-value-maximizing capital structure and pricing policy of insurance groups against that of stand-alone insurers. Groups can utilise intra-group risk diversification by means of capital and risk transfer instruments. We show that using these instruments enables the group to offer insurance with less default risk and at lower premiums than is optimal for standalone insurers. We also take into account that shareholders of groups could find it more difficult to prevent inefficient overinvestment or cross-subsidisation, which we model by higher dead-weight costs of carrying capital. The tradeoff between risk diversification on the one hand and higher dead-weight costs on the other can result in group building being beneficial for shareholders but detrimental for policyholders.
Depending on the point of time and location, insurance companies are subject to different forms of solvency regulation. In modern regulation regimes, such as the future standard Solvency II in the EU, insurance pricing is liberalized and risk-based capital requirements will be introduced. In many economies in Asia and Latin America, on the other hand, supervisors require the prior approval of policy conditions and insurance premiums, but do not conduct risk-based capital regulation. This paper compares the outcome of insurance rate regulation and risk-based capital requirements by deriving stock insurers’ best responses. It turns out that binding price floors affect insurers’ optimal capital structures and induce them to choose higher safety levels. Risk-based capital requirements are a more efficient instrument of solvency regulation and allow for lower insurance premiums, but may come at the cost of investment efforts into adequate risk monitoring systems. The paper derives threshold values for regulator’s investments into risk-based capital regulation and provides starting points for designing a welfare-enhancing insurance regulation scheme.
Background: Patients with cancer have an increased risk of VTE. We compared VTE rates and bleeding complications in 1) cancer patients receiving LMWH or UFH and 2) patients with or without cancer.
Patients with cancer have an increased risk of VTE. We compared VTE rates and bleeding complications in 1) cancer patients receiving LMWH or UFH and 2) patients with or without cancer.
Methods: Acutely-ill, non-surgical patients ≥70 years with (n = 274) or without cancer (n = 2,965) received certoparin 3,000 UaXa o.d. or UFH 5,000 IU t.i.d. for 8-20 days.
Results: 1) Thromboembolic events in cancer patients (proximal DVT, symptomatic non-fatal PE and VTE-related death) occurred at 4.50% with certoparin and 6.03% with UFH (OR 0.73; 95% CI 0.23-2.39). Major bleeding was comparable and minor bleedings (0.75 vs. 5.67%) were nominally less frequent. 7.5% of certoparin and 12.8% of UFH treated patients experienced serious adverse events. 2) Thromboembolic event rates were comparable in patients with or without cancer (5.29 vs. 4.13%) as were bleeding complications. All cause death was increased in cancer (OR 2.68; 95%CI 1.22-5.86). 10.2% of patients with and 5.81% of those without cancer experienced serious adverse events (OR 1.85; 95% CI 1.21-2.81).
Conclusions: Certoparin 3,000 UaXa o.d. and 5,000 IU UFH t.i.d. were equally effective and safe with respect to bleeding complications in patients with cancer. There were no statistically significant differences in the risk of thromboembolic events in patients with or without cancer receiving adequate anticoagulation.
Trial Registration: clinicaltrials.gov, NCT00451412
Depending on the point of time and location, insurance companies are subject to different forms of solvency regulation. In modern regulation regimes, such as the future standard Solvency II in the EU, insurance pricing is liberalized and risk-based capital requirements will be introduced. In many economies in Asia and Latin America, on the other hand, supervisors require the prior approval of policy conditions and insurance premiums, but do not conduct risk-based capital regulation. This paper compares the outcome of insurance rate regulation and riskbased capital requirements by deriving stock insurers’ best responses. It turns out that binding price floors affect insurers’ optimal capital structures and induce them to choose higher safety levels. Risk-based capital requirements are a more efficient instrument of solvency regulation and allow for lower insurance premiums, but may come at the cost of investment efforts into adequate risk monitoring systems. The paper derives threshold values for regulator’s investments into risk-based capital regulation and provides starting points for designing a welfare-enhancing insurance regulation scheme.
Solving the problem of consciousness remains one of the biggest challenges in modern science. One key step towards understanding consciousness is to empirically narrow down neural processes associated with the subjective experience of a particular content. To unravel these neural correlates of consciousness (NCC) a common scientific strategy is to compare perceptual conditions in which consciousness of a particular content is present with those in which it is absent, and to determine differences in measures of brain activity (the so called "contrastive analysis"). However, this comparison appears not to reveal exclusively the NCC, as the NCC proper can be confounded with prerequisites for and consequences of conscious processing of the particular content. This implies that previous results cannot be unequivocally interpreted as reflecting the neural correlates of conscious experience. Here we review evidence supporting this conjecture and suggest experimental strategies to untangle the NCC from the prerequisites and consequences of conscious experience in order to further develop the otherwise valid and valuable contrastive methodology.
RcsF, a proposed auxiliary regulator of the regulation of capsule synthesis (rcs) phosphorelay system, is a key element for understanding the RcsC-D-A/B signaling cascade, which is responsible for the regulation of more than 100 genes and is involved in cell division, motility, biofilm formation, and virulence. The RcsC-D-A/B system is one of the most complex bacterial signal transduction pathways, consisting of several membrane-bound and soluble proteins. RcsF is a lipoprotein attached to the outer membrane and plays an important role in activating the RcsC-d-A/B pathway. The exact mechanism of activation of the rcs phosphorelay by RcsF, however, remains unknown. We have analyzed the sequence of RcsF and identified three structural elements: 1) an N-terminal membrane-anchored helix (residues 3-13), 2) a loop (residues 14-48), and 3) a C-terminal folded domain (residues 49-134). We have determined the structure of this C-terminal domain and started to investigate its interaction with potential partners. Important features of its structure are two disulfide bridges between Cys-74 and Cys-118 and between Cys-109 and Cys-124. To evaluate the importance of this RcsF disulfide bridge network in vivo, we have examined the ability of the full-length protein and of specific Cys mutants to initiate the rcs signaling cascade. The results indicate that the Cys-74/Cys-118 and the Cys-109/Cys-124 residues correlate pairwise with the activity of RcsF. Interaction studies showed a weak interaction with an RNA hairpin. However, no interaction could be detected with reagents that are believed to activate the rcs phosphorelay, such as lysozyme, glucose, or Zn(2+) ions.
Secretins are a family of large bacterial outer membrane protein complexes mediating the transport of complex structures, such as type IV pili, DNA and filamentous phage, or various proteins, such as extracellular enzymes and pathogenicity determinants. PilQ of the thermophilic bacterium Thermus thermophilus HB27 is a member of the secretin family required for natural transformation. Here we report the isolation, structural, and functional analyses of a unique PilQ from T. thermophilus. Native PAGE, gel filtration chromatography, and electrophoretic mobility shift analyses indicated that PilQ forms a macromolecular homopolymeric complex that binds dsDNA. Electron microscopy showed that the PilQ complex is 15 nm wide and 34 nm long and consists of an extraordinary stable "cone" and "cup" structure and five ring structures with a large central channel. Moreover, the electron microscopic images together with secondary structure analyses combined with structural data of type II protein secretion system and type III protein secretion system secretins suggest that the individual rings are formed by conserved domains of alternating α-helices and β-sheets. The unprecedented length of the PilQ complex correlated well with the distance between the inner and outer membrane of T. thermophilus. Indeed, PilQ was found immunologically in both membranes, indicating that the PilQ complex spans the entire cell periphery of T. thermophilus. This is consistent with the hypothesis that PilQ accommodates a PilA4 comprising pseudopilus mediating DNA transport across the outer membrane and periplasmic space in a single-step process.
The transporter associated with antigen processing (TAP) plays a key role in adaptive immunity by translocating proteasomal degradation products from the cytosol into the endoplasmic reticulum lumen for subsequent loading onto major histocompatibility (MHC) class I molecules. For functional and structural analysis of this ATP-binding cassette complex, we established the overexpression of TAP in the methylotrophic yeast Pichia pastoris. Screening of optimal solubilization and purification conditions allowed the isolation of the heterodimeric transport complex, yielding 30 mg of TAP/liter of culture. Detailed analysis of TAP function in the membrane, solubilized, purified, and reconstituted states revealed a direct influence of the native lipid environment on activity. TAP-associated phospholipids, essential for function, were profiled by liquid chromatography Fourier transform mass spectrometry. The antigen translocation activity is stimulated by phosphatidylinositol and -ethanolamine, whereas cholesterol has a negative effect on TAP activity.
Dichlorido(3-phenylindenylidene)bis(triphenylphosphane)ruthenium(II) tetrahydrofuran disolvate
(2011)
The RuII atom in the title compound, [RuCl2(C15H10)(C18H15P)2]·2C4H8O, has a distorted square-pyramidal conformation. The P and Cl atoms are at the base of the pyramid and the Ru-Cindenylidene bond is in the axial position. The two Cl ligands and the two phosphane ligands are in trans positions. The Cl-Ru-Cl and P-Ru-P angles are 157.71 (2) and 166.83 (2)°, respectively. The two independent tetrahydrofuran (THF) solvent molecules are disordered. One THF molecule was refined using a split-atom model. The second THF molecule was accounted for by using program PLATON/SQUEEZE [Spek (2009). Acta Cryst. D65, 148-155]. The molecular conformation shows three intramolecular C-H...Cl contacts and two C-H...[pi] interactions while the crystal packing features an intermolecular C-H...Cl contact and two very weak intermolecular C-H...[pi] contacts.
The title compound, C30H16N4O4, reveals \overline1 crystallographic and molecular symmetry and accordingly the asymmetric unit comprises one half-molecule. The dihedral angle between the planes of the two geminal benzoxazole rings is 74.39 (5)°. The packing features weak C-H...N and [pi]-[pi] interactions [centroid-centroid distance = 3.652 (1) Å].
The avian magnetic compass was analyzed by testing migratory birds, using their orientation as an indicator. These tests revealed some remarkable properties of the avian magnetic compass: (1) It is an inclination compass’, (2) it is light-dependent, with (3) receptors located in the right eye. These characteristics are in agreement with the Radical Pair model proposed by Ritz et al. (2000). Using the same experimental set-up, we tested the model by behavioral spectroscopy’, exposing migratory birds to radiofrequency fields of different frequencies and intensities. Such fields affected the orientation only when applied at an angle to the field lines. Tests with different frequencies led to an estimate of the life time of the crucial radical pair between 2-10 μs. We also could identify an extremely sensitive resonance at the Larmor frequency, which implies specific properties of the radical pair. Cryptochromes, a blue-light absorbing photopigment, has been proposed to be the receptor-molecule; it has been found to be present in the retina of birds.
ATP-binding cassette (ABC) systems translocate a wide range of solutes across cellular membranes. The thermophilic Gram-negative eubacterium Thermus thermophilus, a model organism for structural genomics and systems biology, discloses ∼46 ABC proteins, which are largely uncharacterized. Here, we functionally analyzed the first two and only ABC half-transporters of the hyperthermophilic bacterium, TmrA and TmrB. The ABC system mediates uptake of the drug Hoechst 33342 in inside-out oriented vesicles that is inhibited by verapamil. TmrA and TmrB form a stable heterodimeric complex hydrolyzing ATP with a Km of 0.9 mm and kcat of 9 s−1 at 68 °C. Two nucleotides can be trapped in the heterodimeric ABC complex either by vanadate or by mutation inhibiting ATP hydrolysis. Nucleotide trapping requires permissive temperatures, at which a conformational ATP switch is possible. We further demonstrate that the canonic glutamate 523 of TmrA is essential for rapid conversion of the ATP/ATP-bound complex into its ADP/ATP state, whereas the corresponding aspartate in TmrB (Asp-500) has only a regulatory role. Notably, exchange of this single noncanonic residue into a catalytic glutamate cannot rescue the function of the E523Q/D500E complex, implicating a built-in asymmetry of the complex. However, slow ATP hydrolysis in the newly generated canonic site (D500E) strictly depends on the formation of a posthydrolysis state in the consensus site, indicating an allosteric coupling of both active sites.
The anaerobic acetogenic bacterium Acetobacterium woodii employs a novel type of Na+-motive anaerobic respiration, caffeate respiration. However, this respiration is at the thermodynamic limit of energy conservation, and even worse, in the first step, caffeate is activated by caffeyl-CoA synthetase, which hydrolyzes ATP to AMP and pyrophosphate. Here, we have addressed whether or not the energy stored in the anhydride bond of pyrophosphate is conserved by A. woodii. Inverted membrane vesicles of A. woodii have a membrane-bound pyrophosphatase that catalyzes pyrophosphate hydrolysis at a rate of 70–120 milliunits/mg of protein. Pyrophosphatase activity was dependent on the divalent cation Mg2+. In addition, activity was strictly dependent on Na+ with a Km of 1.1 mm. Hydrolysis of pyrophosphate was accompanied by 22Na+ transport into the lumen of the inverted membrane vesicles. Inhibitor studies revealed that 22Na+ transport was primary and electrogenic. Next to the Na+-motive ferredoxin:NAD+ oxidoreductase (Fno or Rnf), the Na+-pyrophosphatase is the second primary Na+-translocating enzyme in A. woodii.
Pattern recognition approaches, such as the Support Vector Machine (SVM), have been successfully used to classify groups of individuals based on their patterns of brain activity or structure. However these approaches focus on finding group differences and are not applicable to situations where one is interested in accessing deviations from a specific class or population. In the present work we propose an application of the one-class SVM (OC-SVM) to investigate if patterns of fMRI response to sad facial expressions in depressed patients would be classified as outliers in relation to patterns of healthy control subjects. We defined features based on whole brain voxels and anatomical regions. In both cases we found a significant correlation between the OC-SVM predictions and the patients' Hamilton Rating Scale for Depression (HRSD), i.e. the more depressed the patients were the more of an outlier they were. In addition the OC-SVM split the patient groups into two subgroups whose membership was associated with future response to treatment. When applied to region-based features the OC-SVM classified 52% of patients as outliers. However among the patients classified as outliers 70% did not respond to treatment and among those classified as non-outliers 89% responded to treatment. In addition 89% of the healthy controls were classified as non-outliers.
Event-related potentials (ERPs) are widely used in basic neuroscience and in clinical diagnostic procedures. In contrast, neurophysiological insights from ERPs have been limited, as several different mechanisms lead to ERPs. Apart from stereotypically repeated responses (additive evoked responses), these mechanisms are asymmetric amplitude modulations and phase-resetting of ongoing oscillatory activity. Therefore, a method is needed that differentiates between these mechanisms and moreover quantifies the stability of a response. We propose a constrained subspace independent component analysis that exploits the multivariate information present in the all-to-all relationship of recordings over trials. Our method identifies additive evoked activity and quantifies its stability over trials. We evaluate identification performance for biologically plausible simulation data and two neurophysiological test cases: Local field potential (LFP) recordings from a visuo-motor-integration task in the awake behaving macaque and magnetoencephalography (MEG) recordings of steady-state visual evoked fields (SSVEFs). In the LFPs we find additive evoked response contributions in visual areas V2/4 but not in primary motor cortex A4, although visually triggered ERPs were also observed in area A4. MEG-SSVEFs were mainly created by additive evoked response contributions. Our results demonstrate that the identification of additive evoked response contributions is possible both in invasive and in non-invasive electrophysiological recordings.
IL-22 is an immunoregulatory cytokine displaying pathological functions in models of autoimmunity like experimental psoriasis. Understanding molecular mechanisms driving IL-22, together with knowledge on the capacity of current immunosuppressive drugs to target this process, may open an avenue to novel therapeutic options. Here, we sought to characterize regulation of human IL22 gene expression with focus on the established model of Jurkat T cells. Moreover, effects of the prototypic immunosuppressant cyclosporin A (CsA) were investigated. We report that IL-22 induction by TPA/A23187 (T/A) or αCD3 is inhibited by CsA or related FK506. Similar data were obtained with peripheral blood mononuclear cells or purified CD3(+) T cells. IL22 promoter analysis (-1074 to +156 bp) revealed a role of an NF-AT (-95/-91 nt) and a CREB (-194/-190 nt) binding site for gene induction. Indeed, binding of CREB and NF-ATc2, but not c-Rel, under the influence of T/A to those elements could be proven by ChIP. Because CsA has the capability to impair IκB kinase (IKK) complex activation, the IKKα/β inhibitor IKKVII was evaluated. IKKVII likewise reduced IL-22 induction in Jurkat cells and peripheral blood mononuclear cells. Interestingly, transfection of Jurkat cells with siRNA directed against IKKα impaired IL22 gene expression. Data presented suggest that NF-AT, CREB, and IKKα contribute to rapid IL22 gene induction. In particular the crucial role of NF-AT detected herein may form the basis of direct action of CsA on IL-22 expression by T cells, which may contribute to therapeutic efficacy of the drug in autoimmunity.
Recent genome-wide association studies (GWAS) have identified genetic variations near the IL28B gene which are strongly associated with spontaneous and treatment-induced clearance of hepatitis C virus (HCV) infection. Protective IL28B variations are strongly associated with on-treatment viral kinetics and approximately 2-fold increased sustained virologic response (SVR) rates in HCV genotype 1 and 4 patients. In HCV genotype 1 patients, IL28B variations were shown to be the strongest pre-treatment predictor of virologic response. In the treatment of HCV genotype 2 and 3 infected patients, IL28B variations play only a minor role. Preliminary data indicate that IL28B variations are also associated with treatment outcome of regimens, including directly acting antiviral (DAA) agents, though their impact seems to be attenuated compared to standard treatment. Here, we review these important findings and discuss possible implications for clinical decision making in the treatment of HCV infection.
Nosocomial infectious diseases (e.g. influenza, pertussis) are a threat particularly for immunocompromised and vulnerable patients. Although vaccination of healthcare workers (HCWs) constitutes the most convenient and effective means to prevent nosocomial transmissions, vaccine uptake among HCWs remains unacceptably low. Worldwide, numerous studies have demonstrated that nurses have lower vaccination rates than physicians and that there is a relationship between receipt of vaccination by HCWs and knowledge. Measures to improve vaccination rates need to be profession-sensitive as well as specific in their approach in order to achieve sustained success.
Herb induced liver injury (HILI) is a particular challenge that also applies to purported cases presumably caused by black cohosh (BC), an herb commonly used to treat menopausal symptoms. We analyzed and reviewed all published case reports and spontaneous reports of initially alleged BC hepatotoxicity regarding quality of case details and causality assessments. Shortcomings of data quality were more evident in spontaneous reports of regulatory agencies compared to published case reports, but assessments with the scale of CIOMS (Council for the International Organizations of Sciences) or its updated version revealed lack of causality for BC in all cases. The applied causality methods are structured, quantitative, and liver specific with clear preference over an ad hoc causality method or the liver unspecific Naranjo scale. Reviewing the case data and the reports dealing with quality specifications of herbal BC products, there is general lack of analysis with respect to authentication of BC in the BC products used by the patients. However, in one single regulatory study, there was a problem of BC authentication in the analysed BC products, and other reports addressed the question of impurities and adulterants in a few BC products. It is concluded that the use of BC may not exert an overt hepatotoxicity risk, but quality problems in a few BC products were evident that require additional regulatory quality specifications.
Rapidity and transverse momentum dependence of inclusive J/ψ production in pp collisions at √s=7 TeV
(2011)
The ALICE experiment at the LHC has studied inclusive J/ψ production at central and forward rapidities in pp collisions at √s=7 TeV. In this Letter, we report on the first results obtained detecting the J/ψ through the dilepton decay into e+e− and μ+μ− pairs in the rapidity ranges |y|<0.9 and 2.5<y<4, respectively, and with acceptance down to zero pT. In the dielectron channel the analysis was carried out on a data sample corresponding to an integrated luminosity Lint=5.6 nb−1 and the number of signal events is NJ/ψ=352±32(stat.)±28(syst.); the corresponding figures in the dimuon channel are Lint=15.6 nb−1 and NJ/ψ=1924±77(stat.)±144(syst.). The measured production cross sections are σJ/ψ(|y|<0.9)=10.7±1.0(stat.)±1.6(syst.)−2.3+1.6(syst.pol.)μb and σJ/ψ(2.5<y<4)=6.31±0.25(stat.)±0.76(syst.)−1.96+0.95(syst.pol.)μb. The differential cross sections, in transverse momentum and rapidity, of the J/ψ were also measured.
Fragment mass distributions for fission after full momentum transfer were measured in the reactions of 30Si,34,36 S,31P,40Ar + 238U at bombarding energies around the Coulomb barrier. Mass distributions change significantly as a function of incident beam energy. The asymmetric fission probability increases at sub-barrier energy. The phenomenon is interpreted as an enhanced quasifission probability owing to orientation effects on fusion and/or quasifission. The evaporation residue (ER) cross sections were measured in the reactions of 30Si + 238U and 34S + 238U to obtain information on fusion. In the latter reaction, significant suppression of fusion was implied. This suggests that fission events different from compound nucleus are included in the masssymmetric fragments. The results are supported by a model calculation based on a dynamical calculation using Langevin equation, in which the mass distribution for fusion-fission and quasifission fragments are separately determined.
We give a brief overview of recent work examining the presence of α-clusters in light nuclei within the Skyrme-force Hartree-Fock model. Of special signif cance are investigations into α-chain structures in carbon isotopes and 16O. Their stability and possible role in fusion reactions are examined in static and time-dependent Hartree-Fock calculations. We f nd a new type of shape transition in collisions and a centrifugal stabilization of the 4α chain state in a limited range of angular momenta. No stabilization is found for the 3α chain.
The present limits of the upper part of the nuclear map are rather close to the beta stability line while the unexplored area of heavy neutron rich nuclides (also those located along the neutron closed shell N = 126 to the right hand side of the stability line) is extremely important for nuclear astrophysics investigations and, in particular, for the understanding of the r-process of astrophysical nucleogenesis. For elements with Z > 100 only neutron deficient isotopes (located to the left of the stability line) have been synthesized so far. The “north-east” area of the nuclear map can be reached neither in fusion–fission reactions nor in fragmentation processes widely used nowadays for the production of new nuclei. Multi-nucleon transfer processes in near barrier collisions of heavy ions seem to be the only reaction mechanism allowing us to produce and explore neutron rich heavy nuclei including those located at the superheavy island of stability. Neutron capture process can be also considered as an alternative method for the production of long-lived neutron rich superheavy nuclei. Strong neutron fluxes might be provided by nuclear reactors and nuclear explosions in laboratory frame and by supernova explosions in nature.
We found that a true ternary fission with formation of a heavy third fragment (a new kind of radioactivity) is quite possible for superheavy nuclei due to the strong shell effects leading to a three-body clusterization with the two doubly magic tin-like cores. The three-body quasifission process could be even more pronounced for giant nuclear systems formed in collisions of heavy actinide nuclei. In this case a three-body clusterization might be proved experimentally by detection of two coincident lead-like fragments in low-energy U+U collisions.
When taking into consideration the demographic and socio-economic trends in most European countries, the demand for domestic services will be increasing in the next decades. This development could be used for creating formal employment opportunities in private households for unskilled and low-skilled labour. However, it is not an easy task since it entails devising a strategy for reducing the high share of informal labour in as well as overcoming the current fragmentation of the domestic services sector. Both on the national and EU level there is a need for policy advice on how to best integrate the diverse but yet interrelated needs and interests of the households, the employees and the firms as providers of domestic services into one coherent strategy. So far, such a comprehensive strategy can be found only in France where the BorlooPlan systematically integrated measures and tools from all relevant fields of politics. Thus it led to a significant growth of the domestic services sector and a substantial increase of formal employment. This brochure presents the Generalised Model, a tool for devising a similarly comprehensive and coherent strategy. It was constructed by drawing on the successful French strategy of creating more formal employment relationships through the systematic development of the domestic services sector. The brochure demonstrates how other countries can learn from the French experience by analysing their current situation and using the Generalised Model to create a strategy fitting their specific circumstances. By studying the situations in Germany, Austria, Italy and Poland and considering how to create strategies fitting the different national settings in these countries it is shown how the Generalised Model can put into practice. These case studies were conducted in the EU Project “Labour Market Instruments for Reducing Illegal Employment in Private Households of the Elderly”, supported by DG Employment, Social Affairs and Inclusion. The brochure intends to initiate and stimulate discourses on fostering the creation of formal employment in EU Member States. Therefore, it addresses different stakeholders such as policymakers on the national, regional and EU level, representatives of local administrations, providers of domestic services, domestic workers, trade unions or welfare associations, labour administration, placement services as well as providers of education and training.
This rich conversational auto-biography tells the story of the political life of Ndeh Ntumazah who was born in Mankon in 1926, spent the best part of his life suffering and sacrificing for the freedom of Cameroon, and died in London on January 21, 2010, at the age of 83, as President of the Union of the Populations of Cameroon (UPC). Ntumazah was a political activist for nearly 60 years. He joined the UPC around 1950 and remained a militant of the party until his demise. When the UPC was banned in French Cameroon in 1955, he was advised by his comrades to create another party in the Southern Cameroons, which would be the UPC in disguise. The party was called 'One Kamerun Movement - OK', with Ndeh Ntumazah as its President. Following its banning, the UPC started a war of liberation in French Cameoon, so Ntumazah from the safety of Southern Cameroons, liaised with his comrades in French Cameroon to carry out their underground operations. Ndeh Ntumazah left Cameroon to seek political asylum abroad in 1962. He stayed in Ghana, Guinea, Algeria and finally in Britain where he spent most of his time sensitising the world about the plight of Cameroon using various avenues like writing, conferences and deputations. Ntumazah is dead, but he lives on because his life stands out as a point of focus.
There is a general agreement that piracy; counterfeiting and passing off are unfair. However, there is often surreptitious - or even open - sympathy for, say, those who purchase counterfeit designer fashions or the latest technical gadgets. The pirate is even sometimes represented as a daring evil hero. In this book, Prof. Dora Nkem Akunyili, Director General of Nigeria's National Agency for Food and Drug Administration and Control, presents a unique study of a global phenomenon in which law-breaking and profiteering prevail at the cost of human health and life - and of the ways in which this can be fought by appropriate legislation, regulation and enforcement.
Tanzania has been independent in 2011 for 50 years. While most neighbouring states have gone through violent conflicts, Tanzania has managed to implement extensive reforms without armed political conflicts, Hence, Tanzania is an interesting case for Peace and Development research. This dissertation analyses the political development in Tanzania since the introduction of the multiparty system in 1992, with a focus on the challenges for the democratisation process in connection with the 2000 and 2005 elections. The question of to what extent Tanzania had moved towards a consolidation of democracy, is analysed by looking at nine different institutions of importance for democratisation grouped in four spheres: the state, the political, civil and economic society. Focus is on the development of the political society, and the role of the opposition in particular. The analysis is based on secondary and primary material collected between September 2000 to April 2010. The main conclusion is that even if the institutions of liberal democracy have gradually developed, in practice single-party rule has continued, manifested in the 2005 election when the CCM won 92% of seats. Despite impressive economic growth, poverty remains deep and has not been substantially reduced. On a theoretical level this brings the old debate between liberal and substantive democracy back to the fore. Neither the economic nor the political reforms have brought about a transformation of the political and economic system resulting in the poor majority gaining substantially more political influence and improved economic conditions. Hence, it is argued that the interface between the economic, political and administrative reforms has not been sufficiently considered in the liberal democratic tradition. Liberal democracy is necessary for a democratic development, but not sufficient for democracy to be consolidated. For that a substantive democratic development is necessary.
Migration in the Service of African Development : Essays in honour of Professor Aderanti Adepoju
(2011)
Fifteen chapters are included here in this compendium in honour of the Nigerian migration scholar Professor Aderanti Adepoju. Though the authors come from diverse disciplinary backgrounds: geography, demography, sociology and law they all work within the fields of internal and international migration in Africa. Chapters on Uganda, Kenya, Botswana, Nigeria and Mali are devoted to aspects of internal migration, while those on African emigration to Mexico and migration between Burkina Faso and Côte d'Ivoire address various aspects of international migration. Migration issues in relation to women, students and climate change are also discussed.
President Juliys Kambarge Nyerere was the first President of the United Republic of Tanzania and Founder of the Nation. He came into power through the ballot - a democratic process held in 1961, and remained in power for more than two decades. Mwalimu Nyerere was a gifted and morally upright man. He was a true son of Africa - a Pan-Africanist, a nationalist, charismatic orator, steadfast thinker, diplomat and above all a teacher. He chose to be called simply Mwalimu-Teacher. Throughout his term of office he gave hundreds of speeches; some were prepared in advance others given extemporaneously. The Mwalimu Nyerere Foundation (founded by Mwalimu Nyerere himself in 1996) has assembled and put his speeches and writings into books. The Quotations in this book are only those picked from the books in Freedom Series and his University Lectures. They are presented and arranged under the following themes: Philosophy of life, Equality of Man, Colonialism, Tanzania's Revolution, Democracy, Self-reliance, Rural Development, Non-alignment, African Unity, the United Nations, Leadership and Education.
UNICEF estimates that Tanzania has over three million orphans. The Bethsaida Orphan Girls Secondary School seeks to help the ?most vulnerable of Tanzania?s children. Founded by Mrs. Anna Machary in 2005 under the auspices of the non-governmental organization, the Olof Palme Orphans Education Center, the school currently enrolls over 130 orphan girls from all over the country, providing them with free housing, meals, psychological support and a quality secondary education. This book features short stories by thirteen students and has the dual purpose of being a fundraiser for the school and giving the girls a voice. It is a unique and enthralling work of fiction, Their Voices: Their Stories ranges from magical realism to fable, from historical fiction to bildungsroman. Under the professional and passionate editorial guidance of Maryland professor Julie Wakeman-Linn, this collection sings of the fears, anxieties and dreams of young Tanzanian women, who pray their education will be the golden ticket out of lives filled with poverty and abuse.
Older people in Tanzania are disadvantaged and marginalized in many ways. They lack adequate formal social protection. They also suffer from diminishing family and community support. They face a series of multi-faceted problems and care for most AIDS-orphans, yet they are a much neglected target group in national social policy and international development programs. This book provides a theoretical discussion of ageing issues and their linkage to social protection. It depicts various policy frameworks at international, Pan-African and national level. And it provides extensive empirical findings on older people's living conditions.
Never Too Late
(2011)
Images of loneliness, seduction, unfulfilled dreams and torn lives emerge on the pages of this anthology to challenge readers to search for answers for a better life. The authors use The Role of Christianity as the running theme for most of the stories. This is a unique and interesting collection of stories about the life of teenagers. The stories, set in Uganda, offer rare insights into the emotional turbulence and social crises that usually remain unrecognisable and invisible to adults.
How can a black people, who do not even profess to Islam, claim to have originated from Egypt, which is such an Arabic and Islamic geographical setting? But the Kalenjiin people of Kenya have held on fast to a tradition that their ancestors in antiquity were part of ancient Pharaonic Egypt, which they variously call Tto and Misiri. As unlikely as it may sound, the persistence in keeping this oral tradition alive does not seem to be dying with time and distance from the claimed place of origin. The Misiri Legend Explored: A Linguistic Inquiry into the Kalenjiin People's Oral Tradition of Ancient Egyptian Origin establishes the Kalenjin oral tradition of Misirian origin on the basis of linguistic evidence - a genuine tool which Egyptology scholars and researchers need to have relied on much more to bring greater and more final results to their investigations. Students of ancient Egypt willing to accept that there is an irrational prejudice against the concept of ancient black African ingenuity will upgrade their stock of knowledge regarding ancient Egypt with the numerous discoveries laid out here. They will discover a powerful new tool for their trade in the form of the African languages and cultures that now lie South of the Sahara.
In Our Own Tongues gives poetic voice to three generations of African-American women. It celebrates how Black women speak and do in the ways best known to them. This powerful and healing collection of poetry touches on a variety of experiences in the United States regarding emotional abuse, physical and sexual assaults, racism, lynchings, political issues as well as the permeating smell of magnolias.
Justice Mary Ang'awa holds LL.B. and LL.M. degrees from the University of Nairobi. She is an advocate of the High Court of Kenya and a Puisne Judge. She is a fellow of the Chartered Institute of Arbitrators. She has taught the law of succession to judicial officers and advocates of the High Court of Kenya.
Whilst the establishment of the African human rights system was a good gesture that signalled the recognition of the value and essence of international human rights in the continent, a continuous study of the system has become necessary. This is particularly in light of the fact that the continent is in desperate need of well established and effective regional human rights enforcement mechanisms. At the moment, the regional human rights system is stuck between prospects and pitfalls because of the gap that exists between the promise of human rights and their actual realisation. By all means, this trend needs to be reversed. The main objective and purpose of this book is to underscore the challenges besetting the effective enforcement of international human rights law in Africa and the prospects and promises of an effective regional human rights system.
The book is divided into three parts, the first of which deals with Constitutionalism generally. The second part is dedicated to civil liberties and economic rights, namely, fundamental human rights, land and taxation. The last part of the book is dedicated to the Judiciary and its performance as the guardian of the Constitution. A synoptic table of the 1967 Constitution and the DC is included for purposes of general structural comparison.
Disability, Society and Theology: Voices from Africa is the result of a workshop which brought together African theologians, persons with disabilities and disability expertise in the Region to prepare resource materials to enrich the disability study process in the context of the Africa region. The book is in six parts and includes contributions from scholars across the continent. The parts are: Disability Theology: Issue to Debate; The Able Disabled and the Disabled Church: The Church's Response to Disability; Disability and Society; Disability Theology: Some Interfaces; Disability and Caregiving; and Disability in the African Experience.
Cultural memory and narrative theology are well-known hallmarks of postmodern constructivist thought. The author's research into a century of Anglican history in the Mount Kenya region has helped to establish the little known village of Mutira on the world map of the history of Christianity in Africa. This book, a composition of African biographies and mission history, chronicles how the Anglican Church has carried out its work in Mutira area in the past 100 years.
Prison-reformation has been a controversial and politically charged issue in Kenya. In the past it has elicited such legendary and emotional responses as 'What reforms? Prisons are not supposed to be five star hotels!' Recently, however, there has been a greater consensus between the public sector and the civic society in Kenya - than has ever in the past - of the need to revisit the human rights of inmates in various Kenyan prisons. Since 2003 a number of ground breaking reforms have been introduced in Kenyan prisons and more reforms seem to be on the way. Jacqueline Korir in this book takes a serious and despassionate look into a single variable: the quality of catering in Kenyan prisons. Her findings were both shocking and challenging. The food was lacking in both nutritive value as well aesthetic appeal. The site of food samples was only reminiscent of a grotesque meaning of the famous Council in Church History - The Diet of Worms! This book, grounded, in empirical data analysis by hard statistics and backed by rare photographs from inside Kenyan prisons serves as an eye-opener to both the prison-reformists as well as students and teachers of African sociology and institutional catering all over the world.
The Constitution of Kenya: Contemporary Reading, provides an in-depth assessment of the interface between constitutionalism and Kenya's new Constitution. Focusing on the historical trajectory on the search for a new Constitution, Chapter One lays the groundwork upon which the fault line between constitutionalism and the issue areas are articulated in the other chapters in relation to the new Constitution. The superb chapters on the carefully selected issue areas, make this edited volume an essential reading. The book makes an important contribution to the evolving constitutionalism and policy clarification on Kenya's new Constitution. It is a welcome and timely intervention by legal scholars and practitioners on the new constitution and the challenges facing Kenya in its implementation. The book is an excellent teaching and reading manual for students in law, history, politics, diplomacy, and international relations as well as for the practitioners.