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This analysis of the frequency, intensity, and duration of thermal inversions is based on daily minimum (tn) and maximum (tx) temperatures recorded over 3 years at 16 pairs of data loggers located under forest cover in the Jura Mountains of France. Each pair consists of a logger located at the bottom of a depression and another located higher up either nearby (local site) or more than 40 km away (regional site). The daily frequency of inversions is maximum at local sites for tn (50%) and minimum for tx at regional sites (4%). The maximum intensity of the inversions reaches 15.1 °C for tn and 16.2 °C for tx. The average intensity is about 2 °C: 1.5 °C for tx at local sites and 2.4 °C at regional sites. The duration of inversions is generally short: 60% of them last less than a day. Of the inversions that last for more than 1 day, 15% exceed 3 days and the maximum duration observed is 22 days. The relationship between the diurnal amplitude of temperature and the frequency, intensity, and duration of inversions indicates that mesoscale atmospheric conditions directly influence inversions. [ABSTRACT FROM AUTHOR]

This review presents the main class of organophosphorus compounds (triaryl phosphines, phosphazenes, phospholes, phosphetes and diphosphacyclobutanes), which have been used in electronic devices (organic light-emitting diodes (OLEDs), organic photovoltaic cells (OPV cells), dye-sensitized solar cells (DSSCs), organic field-effect transistors (OFETs), and electrochromic cells). [ABSTRACT FROM AUTHOR]

Continued and accelerating change in the thermal environment places an ever-greater priority on understanding how organisms are going to respond. The paradigm of 'move, adapt or die', regarding ways in which organisms can respond to environmental stressors, stimulates intense efforts to predict the future of biodiversity. Assuming that extinction is an unpalatable outcome, researchers have focussed attention on how organisms can shift in their distribution to stay in the same thermal conditions or can stay in the same place by adapting to a changing thermal environment. How likely these respective outcomes might be depends on the answer to a fundamental evolutionary question, namely what genetic changes underpin adaptation to the thermal environment. The increasing access to and decreasing costs of next-generation sequencing (NGS) technologies, which can be applied to both model and non-model systems, provide a much-needed tool for understanding thermal adaptation. Here we consider broadly what is already known from non-NGS studies about thermal adaptation, then discuss the benefits and challenges of different NGS methodologies to add to this knowledge base. We then review published NGS genomics and transcriptomics studies of thermal adaptation to heat stress in metazoans and compare these results with previous non-NGS patterns. We conclude by summarising emerging patterns of genetic response and discussing future directions using these increasingly common techniques. [ABSTRACT FROM AUTHOR]

This paper focuses on the tribological characterization of new martensitic stainless steels by two different tribological methods (scratch and dry wear tests) and their comparison to the austenitic standard stainless steel AISI 316L. The scratch test allows obtaining critical loads, scratch friction coefficients, scratch hardness and specific scratch wear rate, and the dry wear test to quantify wear volumes. The damage has been studied by ex situ scanning electron microscopy. Wear resistance was related to the hardness and the microstructure of the studied materials, where martensitic stainless steels exhibit higher scratch wear resistance than the austenitic one, but higher hardness of the martensitic alloys did not give better scratch resistance when comparing with themselves. It has been proved it is possible to evaluate the scratch wear resistance of bulk stainless steels using scratch test. The austenitic material presented lower wear volume than the martensitic ones after the dry wear test due to phase transformation and the hardening during sliding. [ABSTRACT FROM AUTHOR]

Aim. To understand glucose lowering therapeutic strategies of French general practitioners (GPs) in the management of type 2 diabetes mellitus (T2DM) patients with chronic kidney disease (CKD). Methods. Amulticenter cross-sectional study was conducted from March to June 2011 among a sample of French GPs who contribute to the IMS Lifelink Disease Analyzer database. Eligible patients were those with T2DM and moderate-to-severe CKD who visited their GPs at least once during the study period. Data were collected through electronic medical records and an additional questionnaire. Results. 116GPs included 297 patients: 86 with stage 3a (Group 1, GFR = 45-60 mL/min/1.73m2) and 211 with stages 3b, 4, or 5 (Group 2, GFR < 45 mL/min/1.73m2). Patients' mean age was approximately 75 years. Insulin was used in 19% of patients, and was predominant in those with severe CKD. More than two-thirds of patients were treated with glucose lowering agents which were either contraindicated or not recommended for CKD. Conclusion Physicians most commonly considered the severity of diabetes and not CKD in their therapeutic decision making, exposing patients to potential iatrogenic risks. The recent patient oriented approach and individualization of glycemic objectives according to patient profile rather than standard HbA1c would improve this situation. [ABSTRACT FROM AUTHOR]

In France, haemorrhagic fever with renal syndrome (HFRS) is endemic along the Belgian border. However, this rodent-borne zoonosis caused by the Puumala virus has recently spread south to the Franche-Comté region. We investigated the space–time distribution of HFRS and evaluated the influence of environmental factors that drive the hantavirus reservoir abundance and/or the disease transmission in this area. A scan test clearly indicated space–time clustering, highlighting a single-year (2005) epidemic in the southern part of the region, preceded by a heat-wave 2 years earlier. A Bayesian regression approach showed an association between a variable reflecting biomass (normalized difference vegetation index) and HFRS incidence. The reasons why HFRS cases recently emerged remain largely unknown, and climate parameters alone do not reliably predict outbreaks. Concerted efforts that combine reservoir monitoring, surveillance, and investigation of human cases are warranted to better understand the epidemiological patterns of HFRS in this area. [ABSTRACT FROM PUBLISHER]

Objective: To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in the early detection of residual tumour after radiofrequency ablation (RFA) of renal tumours.Methods: Patients referred to our institution for RFA of renal tumours prospectively underwent CEUS and computed tomography (CT) or magnetic resonance imaging (MRI) before, within 1 day and 6 weeks after treatment. Identification of residual tumour was assessed by three blinded radiologists. Reference standard was CT/MRI performed at least 1 year after RFA.Results: A total of 66 renal tumours in 43 patients (median age 62 years; range 44-71.5) were studied. Inter-reader agreement (kappa value) was 0.84 for CEUS. Prevalence of residual disease was 19%. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), respectively, were as follows: 64% [confidence interval (CI) 39-84], 98% [CI 91-100], 82% [CI 52-95] and 92% [CI 83-97] on 24-h CEUS; 79% [CI 52-92], 100% [CI 94-100], 100% [CI 74-100] and 95% [CI 87-100] on 6-week CEUS; 79% [CI 52-92], 95% [CI 86-98], 79% [CI 52-92] and 95% [CI 86-98] on 24-h CT/MRI; and 100% [CI 72-100], 98% [CI 90-100], 91% [CI 62-98] and 100% [CI 93-100] on 6-week CT/MRI.Conclusion: CEUS has high specificity for the early diagnosis of residual tumour after renal RFA. [ABSTRACT FROM AUTHOR]

In this chapter the fundamental question of how does protein–DNA or protein–RNA interaction affect the structures and dynamics of DNA, RNA and protein is addressed. Models for calf-thymus DNA and transfer RNA interactions with human serum albumin (HSA), ribonuclease A (RNase A) and deoxyribonuclease I (DNase I) are presented here, using Fourier Transform Infrared (FTIR) spectroscopy in conjunction with UV-visible and CD spectroscopic methods. In the models considered, the binding sites, stability and structural aspects of protein–DNA and protein–RNA are discussed and the effects of protein interaction on the secondary structures of DNA, RNA and protein were determined. [ABSTRACT FROM AUTHOR]

Enzyme replacement therapy (ERT) has been used to treat Fabry disease – a progressive lysosomal storage disorder – since 2001. Two preparations of the enzyme α-galactosidase A are available in Europe: agalsidase alpha, produced in a human cell line, and agalsidase beta, produced in Chinese hamster ovary cells. To review critically the published evidence for the clinical efficacy of these two enzyme preparations. A systematic literature search was undertaken to identify open or randomised controlled trials published on Fabry disease since 2001. Eleven trials fulfilled the criteria for inclusion in this review, of a total of 586 references on Fabry disease. To date, no direct comparisons exists between the two available enzyme preparations. Significant clinical benefits compared with placebo, however, have been demonstrated with ERT, with positive effects on the heart, kidneys, nervous system and quality of life. The quality of most of these publications was less than optimal. Further prospective studies are required to confirm the long-term clinical benefits of ERT. More studies are also needed on the effects of ERT in women and on the use of ERT early in the course of Fabry disease, to prevent organ damage. Large national and international outcomes databases will also be invaluable in evaluating treatment effects and safety. [ABSTRACT FROM AUTHOR]

The thermal range for viability is quite variable among Drosophila species and it has long been known that these variations are correlated with geographic distribution: temperate species are on average more cold tolerant but more heat sensitive than tropical species. At both ends of their viability range, sterile males have been observed in all species investigated so far. This symmetrical phenomenon restricts the temperature limits within which permanent cultures can be kept in the laboratory. Thermal heat sterility thresholds are very variable across species from 23 °C in heat sensitive species up to 31 °C in heat tolerant species. In Drosophila melanogaster, genetic variations are observed among geographic populations. Tropical populations are more tolerant to heat induced sterility and recover more rapidly than temperate ones. A genetic analysis revealed that about 50% of the difference observed between natural populations was due to the Y chromosome. Natural populations have not reached a selection limit, however: thermal tolerance was still increased by keeping strains at a high temperature, close to the sterility threshold. On the low temperature side, a symmetrical reverse phenomenon seems to exist: temperate populations are more tolerant to cold than tropical ones. Compared to Mammals, drosophilids exhibit two major differences: first, male sterility occurs not only at high temperature, but also at a low temperature; second, sterility thresholds are not evolutionarily constrained, but highly variable. Altogether, significant and sometimes major genetic variations have been observed between species, between geographic races of the same species, and even between strains kept in the laboratory under different thermal regimes. In each case, it is easily argued that the observed variations correspond to adaptations to climatic conditions, and that male sterility is a significant component of fitness and a target of natural selection. [ABSTRACT FROM AUTHOR]

Sperm competition theory predicts that males should produce many, similar sperm. However, in some species of animals and plants, males exhibit a heteromorphism that results in the production of at least two different types of sperm or pollen grains. In animals, sperm heteromorphism typically corresponds to the production of one fertile morph and one (or more) sterile morph(s), whereas in plants two or more pollen morphs (one of which can be either sterile or fertile) are produced in all flowers but sometimes in different anthers. Heteromorphism has arisen independently several times across phyla and at different phylogenetic levels. Here, we compare and contrast sperm and pollen heteromorphism and discuss the evolutionary hypotheses suggested to explain heteromorphism in these taxa. These hypotheses include facilitation, nutritive contribution, blocking, cheap filler, sperm flushing or killing for animals; outcrossing and precise cross-pollen transfer or bet-hedging strategy for plants; cryptic female choice for both. We conclude that heteromorphism in the two phyla is most likely linked to a general evolutionary response to sexual selection, either to increase one male's sperm or pollen success in competition with other males, or mediate male/female interactions. Therefore, although sperm and pollen are not homologous, we suggest that heteromorphism represents an example of convergence across kingdoms. [ABSTRACT FROM AUTHOR]

The aim of the present study was to determine whether the effects of sex-ratio segregation distorters on the fertility of male Drosophila simulans can explain the contrasting success of these X-linked meiotic drivers in different populations of the species. We compared the fertility of sex-ratio and wild-type males under different mating conditions. Both types were found to be equally fertile when mating was allowed, with two females per male, during the whole period of egg laying. By contrast sex-ratio males suffered a strong fertility disadvantage when they were offered multiple mates for a limited time, or in sperm competition conditions. In the latter case only, the toll on male fertility exceeded the segregation advantage of the distorters. These results indicate that sex-ratio distorters can either spread or disappear from populations, depending on the mating rate. Population density is therefore expected to play a major role in the evolution of sex-ratio distorters in this Drosophila species. [ABSTRACT FROM AUTHOR]

The dibenzofuran usnic acid is an important secondary lichen metabolite, having many postulated biological roles, but evidence from field surveys is scanty. Trends in usnic acid concentrations and lobe width in the arctic lichen Flavocetraria nivalis were analysed along local longitudinal and altitudinal gradients in the Kongsfjorden area, northwestern Spitsbergen. Temperature was measured along the same gradients during 1 year. Other environmental variables were also estimated. The model that best explains the variability in usnic-acid levels includes the parameters effective temperature sum, frost sum and temperature range. Temperature range indicates a relationship between high usnic acid levels and humidity, whereas the two first parameters indicate a relationship with low temperatures, which could be direct or indirect. Much of the variability in usnic acid levels and lobe width could not be explained by the selected models. Thus, the secondary metabolism and lobe growth in this lichen is a complex matter, involving numerous environmental and possibly also intrinsic factors. [ABSTRACT FROM AUTHOR]

In the Arctic, plant species are at their physiological tolerance limit. Anthropogenic induced climate changes may thus have fundamental consequences on arctic plant life in the near future. Summer temperatures are by far the most important factor determining the general distribution of plants over large areas. According to different meteorological stations, mean July temperature on Svalbard is in the range 2-6°C. Nevertheless, there are large local gradients in the Svalbard landscape. A method has been developed that uses the plants as climate indicators. This index of thermophily uses the whole species diversity, with increasing values based on increasing concentrations of plants requiring higher temperatures within the temperature range cited from Svalbard above. This index can be useful for predicting scenarios about development of arctic vegetation due to the global change effects if we can determine the environmental factors controlling its spatial variation. The function of these environmental variables is analysed according to a regional and a local scale. At each scale, modelling index of thermophily values distribution is done within a GIS, using different variables as predictors. At the regional scale, covering the Brøggerhalvøya peninsula, spatial distribution of index values is correlated with latitude and longitude and shows a continentality effect. At the local scale, other predictors like topography (gradient, aspect, altitude) and satellite data (NDVI, temperature from TM6, classification results) are tested. Finally, a combination of the models for the different scales enables us to map the distribution of index of thermophily. [ABSTRACT FROM AUTHOR]

Many diverse traits are involved in gamete systems, and several models have analysed sperm length variation in terms of the intensity of sperm competition. This study investigates mating, sperm transfer and oviposition patterns in Drosophila bifurca, which possesses the longest sperm in the animal kingdom (about 6 cm). The prediction is that sperm gigantism should prevent male–male interaction. In this study, we examine how sperm transfer varies as males mate with a series of females, and how female receptivity changes with time after mating. As predicted, we found an extremely limited overlap of ejaculates owing to (1) reduced sperm transfer to females that had already mated, and (2) female remating depended both on the amount of sperm transferred and the modes of egg laying. The amount of sperm transferred to the female is discussed in relation to the peculiar morphology of the male reproductive tract and to sexual dimorphism and ecological hypotheses. [ABSTRACT FROM AUTHOR]

Renal dysfunction is a major complication in hemizygous males with Fabry disease. This often results in end-stage renal failure (ESRF), requiring dialysis or transplantation, on average 10 years after the start of renal impairment. ESRF usually occurs between 40 and 50 years of age, but may occur much earlier. Although progression of renal disease can be rapid, it is variable and may depend on whether there is residual α-galactosidase enzyme activity and on environmental or genetic factors. Significant renal disease is much less common in women carriers of the disease. However, renal changes do occur, which may progress to ESRF as in male patients. [ABSTRACT FROM AUTHOR]

The article discusses the life expectancy and treatment of Fabry disease (FD). It mentions that FD is a rare genetic lysosomal storage disease, inherited in an X-linked manner. It notes the cause of death of males and females with FD and the long-term outcome of enzyme replacement therapy (ERT) in advanced FD.

Vegetation and environmental data were collected at 266 sampling points distributed in a regular manner along transects covering the Broggerhalvoya peninsula, on the north-western coast of Spitsbergen. Transects with sampling points were drawn in advance on aerial photographs. The analysis of releves and collection of ground data along transects represent an efficient, representative and precise way of sampling. The vegetation data were classified and 19 plant communities distinguished. The plant communities were subjected to detrended correspondence analysis (DCA). Among the recorded variables, moisture is the one with the highest correlation along axes one and two, and reflects a coincidental moisture and vegetation cover gradient. The vegetation component responsible for this positive correlation is the bryophytes. Likewise, the TWINSPAN classification confirms this gradient in a dendrogram reflecting the hierarchical structure of the plant communities. Plant communities constitute the base of a statistical model that links the communities and the SPOT satellite data. The model then classifies and maps plant communities by means of satellite data, covering the entire Broggerhalvoya peninsula. Satellite data and environmental data were analysed regarding their ability to distinguish the plant communities in a discriminant function analysis (DFA). The results of the DFA indicate that it may be reasonable to include all the information from the different satellite channels when using satellite data for vegetation classification purposes. Among the satellite data the panchromatic channel is the one adding the most unique information to the power of the model in separating plant communities. The classification of satellite data using the probability model indicates that plant communities with less than 30% vegetation cover could be classified with the same degree of confidence or better, as compared with plant communities with more than 30% vegetation cover. The overall percentage of correctly classified releves increased by 13% when using probability level two instead of level one (57.8 to 71.1%). The probability classification model makes it possible to experiment with different probability levels to improve the fit between the vegetation and satellite data classification. [ABSTRACT FROM AUTHOR]

Abstract The vegetation of a 5km2 area in front of the Midtre Lovenbreen glacier, Northwest Spitsbergen, Svalbard, was mapped on the scale 1 10000. The main aim of the study was to develop a new method of vegetation classification based on a probability model, and apply the method on a digitized aerial colour infrared (CIR) photograph with a better ground resolution than provided by the Landsat and SPOT satellites. Large-scale data from different sources such as the CIR-aerial photograph, information layers derived from a digital elevation model (DEM) and vegetation sampling in the field have been integrated in a GIS. Probability models build the links between GIS data layers and plant communities resulting from classification of field data. Eight plant communities were defined by means of vegetation data and mapped automatically by classification of the CIR-photograph. Based on the probability model, maps were produced showing the actual and potential distribution of plant communities. The accuracy of the vegetation map was improved by including additional information from the DEM. [ABSTRACT FROM AUTHOR]

The sex-ratio trait, known in several Drosophila species, results from X-linked meiotic drive that affects Y-bearing sperm and causes males to produce female-biased progeny. We describe spermiogenesis in three types of D. simulans males: wild-type, sex-ratio, and males that bear driver X chromosomes but do not express the sex-ratio trait because of autosomal and Y-linked suppression. Sex-ratio males show numerous spermatid nuclei in abnormal positions throughout their cysts, which occurs rarely, if ever, in the two other types. The degree of the spermiogenic failure in sex-ratio males is correlated with the bias towards females in their progeny. This proves that the trait is a case of meiotic drive and strongly suggests that the abnormal spermatids are Y-bearing ones. The number of cysts per testis, hence the production of X-bearing sperm, is not increased in sex-ratio males. Implications for the spread of the sex-ratio trait in natural populations of D. simulans are discussed. [ABSTRACT FROM AUTHOR]

Recent studies have shown that several compounds known to act as competitive or non-competitive antagonists of NMDA receptors can disrupt learning in rodents. The present study was carried out to investigate the effects of a range of NMDA antagonists, acting at several sites in the NMDA receptor complex, on the acquisition of learned fear in mice. Dose-related disruptions of learning were produced by the non-competitive antagonists phencyclidine, dizocilpine, dextromethorphan and (+) and (−)N-allylnormetazocine. The (+) enantiomer of N-allylnormetazocine was approximately twice as potent as the (−) enantiomer. The competitive NMDA receptor antagonist, CGS 19755, also blocked the acquisition of learned fear as did the non-specific glutamate antagonist riluzole. In contrast, the antiischaemic drugs ifenprodil and SL 82.0715, which probably act as NMDA antagonists through an effect on the polyamine site, had no effect on learning up to doses which substantially reduced locomotion. The sigma receptor ligand DTG was also inactive. These results confirm that both competitive and non-competitive NMDA antagonists disrupt learning but indicate that the extent to which such an effect is observed may depend on the site at which the compounds act within the receptor complex. Activity at sigma receptors is unrelated to the effect on learning. [ABSTRACT FROM AUTHOR]

Benzodiazepines and other compounds which act at benzodiazepine binding sites have been shown previously to attenuate the acquisition of conditioned fear in rodents when administered before the acquisition session, an effect which may parallel the disruption of human memory produced by anxiolytics and sedatives. Such an action is usually, but not invariably, produced by doses which have direct behavioural depressant effects. The present study was carried out to extend previous work by investigating the effects of the hypnotic benzodiazepine triazolam and the nonbenzodiazepines zolpidem and CL 218,872 on the acquisition of learned fear in mice. All these drugs reduced locomotor activity shortly after injection. They also produced disruptions of the acquisition of learned fear. Triazolam exerted behavioural effects similar to those found previously with other benzodiazepines, the doses which disrupted the acquisition of conditioned fear being similar to, or lower than, the doses which depressed locomotion. In contrast, the results indicated that zolpidem was more potent at reducing locomotion than at interfering with fear conditioning, a result which may reflect the preferential sedative action of zolpidem. [ABSTRACT FROM AUTHOR]

Previous studies have shown that, in rodents, chlordiazepoxide and other benzodiazepines can interfere with learning in passive avoidance or conditioned suppression procedures. The most consistent effects are observed when the drugs are administered before the acquisition trial and subjects are re-tested in the non-drugged state. It is not clear, however, whether this effect on learning is associated with the behavioural depressant actions of these drugs. In the present study mice were injected with chlordiazepoxide, diazepam, zopiclone, or CGS 9896 and locomotor activity measured in a two-compartment box. The animals were then enclosed in one of the compartments and received a series of footshocks. On a second trial, 24 h after the first, the mice were returned to the box without injection and locomotion and time spent in each compartment were measured. During trial 1 chlordiazepoxide, diazepam, and zopiclone produced dose-related decreases in locomotor activity. The same doses disrupted fear conditioning. CGS 9896 also interfered with the conditioning of fear but did not reduce exploratory activity during the first trial at any of a wide range of doses, showing that learning can be affected without direct behavioural depressant activity. In a further experiment, chlordiazepoxide and CGS 9896 disrupted fear conditioning when injected before trial 1 but not when injected immediately after this trial. Mice drugged with chlordiazepoxide or CGS 9896 before both trials 1 and 2 also showed disrupted conditioning, demonstrating that the drug effects cannot be interpreted in terms of state dependent learning. [ABSTRACT FROM AUTHOR]

We reviewed 11 cases of intramedullary cavernous haemangiomas (IMCH) studied by MRI, to assess its diagnostic value in these lesions. Follow-up MRI was obtained in five patients 7 days-2 years following the initial study. In one case a postoperative examination was obtained. The diagnosis was pathologically proven in ten cases, and supported in the last by a family and personal history of cavernous haemangiomas. A reticulate appearance with areas of mixed signal intensity in both T1-and T2-weighted images was the most common finding. Homogeneous high, low or intermediate signal intensity was each found in one case, Two small lesions gave low signal. A rim of low signal was less common than in cerebral cavernous haemangiomas. In one case, the brain showed more than 20 lesions with the MRI appearances of cavernous haemangiomas. In two of five patients, serial preoperative MRI showed progressive disappearance of high-signal areas on both T1-and T2-weighted images. To find a haemorrhagic intramedullary lesion on MRI is not rare. Although the appearances are not pathognomonic, an IMCH can be suggested. We suggest that the following characteristics may help: (1) a personal and/or family history of cavernous haemangiomas; (2) typical MRI appearances of mixed acute, subacute and chronic haemorrhage; (3) a tendency for signal intensity to decrease on follow-up; (4) normal spinal angiography; and (5) associated brain lesions. [ABSTRACT FROM AUTHOR]

Technical advances in the field of ultrasound have resulted in the development of a high resolution real-time B-mode imaging system that permits direct Doppler analysis of hemodynamic abnormalities. This system combines both anatomic information and physiological information which permits detailed analysis of the entire spectrum of disease occurring at the carotid bifurcation. Future developments will permit improved management of patients at risk for stroke from carotid vascular disease. [ABSTRACT FROM AUTHOR]

It is well established that benzodiazepines can produce anterograde amnesia in humans and interfere with the acquisition of passive avoidance and spatial responses in rodents. However, the extent to which the disruption of learning is a secondary effect of the sedation produced by these drugs has not been clearly established. In order to investigate this question, the effects of several BZ (ω) receptor partial agonists were studied on the acquisition of conditioned fear (passive avoidance learning) in mice. As these drugs have been shown to produce anticonvulsant and anxiolytic-like effects without sedation or depression of motor activity, it was of interest to see whether they could disrupt learning. Clear effects on the acquisition of conditioned fear were produced by imidazenil (0.01-1.0 mg/kg), divaplon (1-60 mg/kg), ZK 91296 (3-60 mg/kg), and Ro 17-1812 (0.1-10 mg/kg). However, bretazenil (0.1-10 mg/kg) did not produce statistically significant effects. Only the high dose of imidazenil (1.0 mg/kg) decreased levels of exploratory behaviour. These results show that BZ (ω) receptor partial agonists without apparent sedative actions can disrupt fear learning, indicating that the effects of this class of drugs on passive avoidance learning can be dissociated from sedation. The reasons for the observed differences between the different compounds studied are unclear at present and may be related to differences in intrinsic activity or receptor subtype selectivity. [ABSTRACT FROM AUTHOR]

In order to test the validity of the prediction of the mating pattern of females from the sperm length distribution in males, three species of Drosophila were analysed. Males in the three species are equally polygynous but females differ in the level of polyandry. A 'low recurrence polyandry' is observed in the sperm dimorphic species D. affinis while a 'high recurrence polyandry' is observed in the sperm monomorphic species D. latifasciaeformis and D. littoralis. These results are consistent with the hypothesis proposed previously that sperm dimorphism in males can only be maintained by a selective alternative in females (i.e. facultative female polygamy), whereas a stricter mating system (e.g., 'obligatory' polyandry) should only result in sperm monomorphism irrespective of the absolute value of sperm length. [ABSTRACT FROM AUTHOR]

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When Drosophila simulans females from the Seychelles are crossed with D. mauritiana males the number of hybrids produced decreases with an increase in, both density of flies and male/female proportion. The patterns are consistent in the reciprocal cross although the number of progeny is reduced. The asymmetry of mating success affects not only mating preference and the outcome of the cross, but also the progeny numbers. [ABSTRACT FROM AUTHOR]

An introduction is presented in which the editor discusses various reports within the issue on topics including the structure functioning of bacterial populations in different environments, the genes and single nuceleotide polymorphisms under selection, and the characterization of adaptive genes.

Through the examination of key issues and regional studies this book argues that asylum regimes throughout the world display convergent trends. It links human rights and asylum and explodes the myth of international protection. It analyses temporary protection based on the European model. The author draws lessons from international protection in Kosovo and evaluates European Union harmonization initiatives. This study stresses the role of refugees as social actors and develops the complexity of gender and refugee women’s issues. It maps out theoretical and policy issues relating to return in Africa and explores the relationship between asylum law and liberal governance; and it demonstrates the changing role of human rights organizations. [ABSTRACT FROM AUTHOR]

Through the examination of key issues and regional studies this book states that asylum regimes throughout the world display convergent trends. It links human rights and asylum, and analyzes temporary protection based on the European model. It also draws lessons from international protection in Kosovo and evaluates European Union harmonization initiatives. This study stresses the role of refugees as social actors, develops the complexity of gender and refugee women’s issues and maps out theoretical and policy issues relating to return in Africa. Finally, it explores the relationships between asylum law and liberal government and demonstrates the changing role of human rights organizations. [ABSTRACT FROM AUTHOR]