Summary Recently, it has been shown that Charcot-Marie-Tooth disease type 1a (CMT1a) is linked with a duplication of a DNA segment that is detected by probe VAW409R3, and that is located on chromosome 17p11.2. Here, we show that this duplication also contains VAW412R3a, but not A10-41 and EW503. Accounting for the duplication in recombination analysis, we found recombinants between CMT1a and EW301 and EW502, but not with A10-41, VAW409R3, and VAW412R3. Using pulsed-field gel electrophoresis analysis, we estimated the minimal size of the duplicated region in CMT1a patients to be 1100 kb. 相似文献
Very small angle neutron scattering studies have been made on intact nuclei under a variety of solution conditions. Scattering maxima are observed at 30 to 40 nm and at 18 nm in most environments. Although the spacing, intensity and presence of the maximum near 40 nm varies considerably with environment the 18 nm is rather constant. The 30 to 40 nm maximum appears to be best interpreted by the presence of 35 to 50 nm diameter fibers in nuclei. An important result is that no scattering maximum was observed near 11 nm, suggesting that a tightly super coiled nucleofilament with such a pitch is not present. 相似文献
Despite its central place in animal ecology no general mechanistic movement model with an emergent home-range pattern has yet been proposed. Random walk models, which are commonly used to model animal movement, show diffusion instead of a bounded home range and therefore require special modifications. Current approaches for mechanistic modeling of home ranges apply only to a limited set of taxa, namely territorial animals and/or central place foragers. In this paper we present a more general mechanistic movement model based on a biased correlated random walk, which shows the potential for home-range behavior. The model is based on an animal tracking a dynamic resource landscape, using a biologically plausible two-part memory system, i.e. a reference- and a working-memory. Our results show that by adding these memory processes the random walker produces home-range behavior as it gains experience, which also leads to more efficient resource use. Interestingly, home-range patterns, which we assessed based on home-range overlap and increase in area covered with time, require the combined action of both memory components to emerge. Our model has the potential to predict home-range size and can be used for comparative analysis of the mechanisms shaping home-range patterns. 相似文献
Ecological and evolutionary processes in temporary rock pools operate within constraints imposed by their hydrologic regimes.
These shallow pools flood when seasonal rains accumulate on impermeable substrates. Despite the ecological importance of hydrologic
conditions for these ecosystems, we typically lack tools and empirical data required to understand the implications of hydrologic
variability and climate change for biotic populations and communities in these habitats. In this study, we developed a hydrologic
model to simulate rock pool hydrologic regimes based on rainfall, evapotranspiration, and basin geometry. The model was used
to investigate long-term patterns of seasonal and inter-annual variation in hydroregime. In addition, hydrologic conditions
associated with potential climate change scenarios were simulated and evaluated with respect to the biological requirements
of the anostracan Branchipodopsis wolfi. The model’s output for daily inundation matched with field observations with an overall accuracy of 85% and correctly estimated
complete hydroperiods with an overall accuracy of 70%. Simulations indicate large variation in individual hydroperiods (76–115%)
as well as in the number of hydroperiods per year (19–23%). Furthermore, this study suggests that climate change may significantly
alter the rock pool hydroregime. These findings confirm the hydrologic sensitivity of these ephemeral habitats to precipitation
patterns, and their potential sensitivity to future climate change. Modelling indicates that the suitability of average inundation
conditions for B. wolfi deteriorates significantly under future climate predictions. High levels of spatial and temporal variation in hydrologic
conditions are dominant features of these habitats and an essential consideration for understanding population and community-level
ecological processes. 相似文献
RNA viruses are a leading cause of human infectious diseases and the prediction of where new RNA viruses are likely to be discovered is a significant public health concern. Here, we geocoded the first peer-reviewed reports of 223 human RNA viruses. Using a boosted regression tree model, we matched these virus data with 33 explanatory factors related to natural virus distribution and research effort to predict the probability of virus discovery across the globe in 2010–2019. Stratified analyses by virus transmissibility and transmission mode were also performed. The historical discovery of human RNA viruses has been concentrated in eastern North America, Europe, central Africa, eastern Australia, and north-eastern South America. The virus discovery can be predicted by a combination of socio-economic, land use, climate, and biodiversity variables. Remarkably, vector-borne viruses and strictly zoonotic viruses are more associated with climate and biodiversity whereas non-vector-borne viruses and human transmissible viruses are more associated with GDP and urbanization. The areas with the highest predicted probability for 2010–2019 include three new regions including East and Southeast Asia, India, and Central America, which likely reflect both increasing surveillance and diversity of their virome. Our findings can inform priority regions for investment in surveillance systems for new human RNA viruses. 相似文献
The compliance of the proximal aortic wall is a major determinant of cardiac afterload. Aortic compliance is often estimated based on cross-sectional area changes over the pulse pressure, under the assumption of a negligible longitudinal stretch during the pulse. However, the proximal aorta is subjected to significant axial stretch during cardiac contraction. In the present study, we sought to evaluate the importance of axial stretch on compliance estimation by undertaking both an in silico and an in vivo approach. In the computational analysis, we developed a 3-D finite element model of the proximal aorta and investigated the discrepancy between the actual wall compliance to the value estimated after neglecting the longitudinal stretch of the aorta. A parameter sensitivity analysis was further conducted to show how increased material stiffness and increased aortic root motion might amplify the estimation errors (discrepancies between actual and estimated distensibility ranging from − 20 to − 62%). Axial and circumferential aortic deformation during ventricular contraction was also evaluated in vivo based on MR images of the aorta of 3 healthy young volunteers. The in vivo results were in good qualitative agreement with the computational analysis (underestimation errors ranging from − 26 to − 44%, with increased errors reflecting higher aortic root displacement). Both the in silico and in vivo findings suggest that neglecting the longitudinal strain during contraction might lead to severe underestimation of local aortic compliance, particularly in the case of women who tend to have higher aortic root motion or in subjects with stiff aortas.
Nazi eugenics is one of the main historical events influencing current popular as well as scholarly discussions of reproductive genetics. This influence, however, is open to different interpretations and social constructions. Based on 44 open interviews with Israeli and German genetic counselors, conducted in 2000–2003, our findings suggest that while the majority of German counselors reflected on Nazi eugenics as setting moral limits for contemporary repro-genetics, many Israeli counselors detached their contemporary practice from the wrongdoings of the past. Correspondingly, German counselors were far more sensitive towards the disability critique of repro-genetics than their Israeli counterparts. We conclude with a discussion of these two opposite positions, suggesting that the comparison of German and Israeli professionals reveals a profound complexity and involvedness in coming to terms with the “eugenic” lessons of the Holocaust, on both sides. In Germany, potential benefits of repro-genetics might be rejected due to an emphasis on a more universalistic lesson of the Holocaust regarding the value of human life and dignity. In Israel, a more particularistic lesson of the Holocaust regarding national Jewish survival, combined with a lack of public debate regarding medicalization and geneticization, might have promoted the advent of unregulated commercially and consumer-driven repro-genetics. 相似文献
The relative importance of deterministic and stochastic processes driving patterns of human settlement remains controversial. A main reason for this is that disentangling the drivers of distributions and geographic clustering at different spatial scales is not straightforward and powerful analytical toolboxes able to deal with this type of data are largely deficient. Here we use a multivariate statistical framework originally developed in community ecology, to infer the relative importance of spatial and environmental drivers of human settlement. Using Moran’s eigenvector maps and a dataset of spatial variation in a set of relevant environmental variables we applied a variation partitioning procedure based on redundancy analysis models to assess the relative importance of spatial and environmental processes explaining settlement patterns. We applied this method on an archaeological dataset covering a 15 km2 area in SW Turkey spanning a time period of 8000 years from the Late Neolithic/Early Chalcolithic up to the Byzantine period. Variation partitioning revealed both significant unique and commonly explained effects of environmental and spatial variables. Land cover and water availability were the dominant environmental determinants of human settlement throughout the study period, supporting the theory of the presence of farming communities. Spatial clustering was mainly restricted to small spatial scales. Significant spatial clustering independent of environmental gradients was also detected which can be indicative of expansion into unsuitable areas or an unexpected absence in suitable areas which could be caused by dispersal limitation. Integrating historic settlement patterns as additional predictor variables resulted in more explained variation reflecting temporal autocorrelation in settlement locations. 相似文献