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941.
Ernst Rüdin (1874–1952) was the founder of psychiatric genetics and was also a founder of the German racial hygiene movement. Throughout his long career he played a major role in promoting eugenic ideas and policies in Germany, including helping formulate the 1933 Nazi eugenic sterilization law and other governmental policies directed against the alleged carriers of genetic defects. In the 1940s Rüdin supported the killing of children and mental patients under a Nazi program euphemistically called “Euthanasia.” The authors document these crimes and discuss their implications, and also present translations of two publications Rüdin co-authored in 1938 showing his strong support for Hitler and his policies. The authors also document what they see as revisionist historical accounts by leading psychiatric genetic authors. They outline three categories of contemporary psychiatric genetic accounts of Rüdin and his work: (A) those who write about German psychiatric genetics in the Nazi period, but either fail to mention Rüdin at all, or cast him in a favorable light; (B) those who acknowledge that Rüdin helped promote eugenic sterilization and/or may have worked with the Nazis, but generally paint a positive picture of Rüdin’s research and fail to mention his participation in the “euthanasia” killing program; and (C) those who have written that Rüdin committed and supported unspeakable atrocities. The authors conclude by calling on the leaders of psychiatric genetics to produce a detailed and complete account of their field’s history, including all of the documented crimes committed by Rüdin and his associates. 相似文献
942.
Frank Maldarelli Mary Kearney Sarah Palmer Robert Stephens JoAnn Mican Michael A. Polis Richard T. Davey Joseph Kovacs Wei Shao Diane Rock-Kress Julia A. Metcalf Catherine Rehm Sarah E. Greer Daniel L. Lucey Kristen Danley Harvey Alter John W. Mellors John M. Coffin 《Journal of virology》2013,87(18):10313-10323
HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIV pro-pol to assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n = 22) or multiple, longitudinal (n = 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift. 相似文献
943.
Árpád S. Nyári Leo Joseph 《Biological journal of the Linnean Society. Linnean Society of London》2013,109(3):574-598
The world's richest mangrove‐restricted avifauna is in Australia and New Guinea. The history of differentiation of the species involved and their patterns of intraspecific genetic variation remain poorly known. Here, we use sequence data derived from two mitochondrial protein‐coding genes to study the evolutionary history of eight co‐distributed mangrove‐restricted and mangrove‐associated birds from the Australian part of this region. Utilizing a comparative phylogeographical framework, we observed that the study species present concordantly located phylogeographical breaks across their shared geographical distribution, a plausible signature of common mechanisms of vicariance underlying this pattern. Barriers such as the Canning Gap, Bonaparte Gap, and the Carpentarian Gaps all had important but varying degrees of impact on the studied species. The Burdekin Gap along Australia's eastern seaboard probably had only a minor influence as a barrier to gene flow in mangrove birds. Statistical phylogeographical simulations were able to discriminate among alternative scenarios involving six different geographical and temporal population separations. Species exhibiting recent colonizations into mangroves include Rhipidura phasiana, Myiagra ruficollis, and Myzomela erythrocephala. By contrast, Peneoenanthe pulverulenta, Pachycephala melanura, Pachycephala lanioides, Zosterops luteus, and Colluricincla megarhyncha all had deeper histories, reflected as more marked phylogeographical divisions separating populations on the eastern seaboard/Cape York Peninsula from more western regions such as the Arnhem Land, the Pilbara, and the Kimberley. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 109 , 574–598. 相似文献
945.
Richard Atherton Darlene Bhavnani Manuel Calvopi?a Yosselin Vicu?a William Cevallos Joseph Eisenberg 《Memórias do Instituto Oswaldo Cruz》2013,108(4):512-515
The aim of this study was to determine the genetic diversity of
Giardia duodenalis present in a human population living in
a northern Ecuadorian rain forest. All Giardia positive samples
(based on an ELISA assay) were analysed using a semi-nested polymerase chain
reaction-restriction fragment length polymorphism assay that targets the
glutamate dehydrogenase (gdh) gene; those amplified were
subsequently genotyped using NlaIV and RsaI enzymes. The gdh
gene was successfully amplified in 74 of 154 ELISA positive samples; 69 of the
74 samples were subsequently genotyped. Of these 69 samples, 42 (61%) were
classified as assemblage B (26 as BIII and 16 as BIV), 22 (32%) as assemblage A
(3 as AI and 19 as AII) and five (7%) as mixed AII and BIII types. In this study
site we observe similar diversity in genotypes to other regions in Latin
America, though in contrast to some previous studies, we found similar levels of
diarrheal symptoms in those individuals infected with assemblage B compared with
those infected with assemblage A. 相似文献
946.
Donna S. Francy Erin A. Stelzer Joseph W. Duris Amie M. G. Brady John H. Harrison Heather E. Johnson Michael W. Ware 《Applied and environmental microbiology》2013,79(5):1676-1688
Predictive models, based on environmental and water quality variables, have been used to improve the timeliness and accuracy of recreational water quality assessments, but their effectiveness has not been studied in inland waters. Sampling at eight inland recreational lakes in Ohio was done in order to investigate using predictive models for Escherichia coli and to understand the links between E. coli concentrations, predictive variables, and pathogens. Based upon results from 21 beach sites, models were developed for 13 sites, and the most predictive variables were rainfall, wind direction and speed, turbidity, and water temperature. Models were not developed at sites where the E. coli standard was seldom exceeded. Models were validated at nine sites during an independent year. At three sites, the model resulted in increased correct responses, sensitivities, and specificities compared to use of the previous day''s E. coli concentration (the current method). Drought conditions during the validation year precluded being able to adequately assess model performance at most of the other sites. Cryptosporidium, adenovirus, eaeA (E. coli), ipaH (Shigella), and spvC (Salmonella) were found in at least 20% of samples collected for pathogens at five sites. The presence or absence of the three bacterial genes was related to some of the model variables but was not consistently related to E. coli concentrations. Predictive models were not effective at all inland lake sites; however, their use at two lakes with high swimmer densities will provide better estimates of public health risk than current methods and will be a valuable resource for beach managers and the public. 相似文献
947.
Jessica Laskowski Caitlyn Gillespie Lucia Corral Amy Oden Kent Fricke Joseph J. Fontaine 《Science activities》2013,50(4):147-154
We present a hands-on outdoor activity coupled with classroom discussion to teach students about wildlife habitat selection, the process by which animals choose where to live. By selecting locations or habitats with many benefits (e.g., food, shelter, mates) and few costs (e.g., predators), animals improve their ability to survive and reproduce. Biologists track animal movement using radio telemetry technology to study habitat selection so they can better provide species with habitats that promote population growth. We present a curriculum in which students locate “animals” (transmitters) using radio telemetry equipment and apply math skills (use of fractions and percentages) to assess their “animal's” habitat selection by comparing the availability of habitat types with the proportion of “animals” they find in each habitat type. 相似文献
948.
Amir Sherman Ravit Eshed Rotem Harel-Beja Galil Tzuri Vitaly Portnoy Shahar Cohen Mor Rubinstein Arthur A. Schaffer Joseph Burger Nurit Katzir Ron Ophir 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2013,126(2):349-358
The availability of sequence information for many plants has opened the way to advanced genetic analysis in many non-model plants. Nevertheless, exploration of genetic variation on a large scale and its use as a tool for the identification of traits of interest are still rare. In this study, we combined a bulk segregation approach with our own-designed microarrays to map the pH locus that influences fruit pH in melon. Using these technologies, we identified a set of markers that are genetically linked to the pH trait. Further analysis using a set of melon cultivars demonstrated that some of these markers are tightly linked to the pH trait throughout our germplasm collection. These results validate the utility of combining microarray technology with a bulk segregation approach in mapping traits of interest in non-model plants. 相似文献
949.
950.
Chad D. Edwards Joseph C. Beatty Jacqueline B. R. Loiselle Katya A. Vlassov Daniel D. Lefebvre 《Applied microbiology and biotechnology》2013,97(8):3613-3623
Industrial activity over the last two centuries has increased heavy metal contamination worldwide, leading to greater human exposure. Zinc is particularly common in industrial effluents and although an essential nutrient, it is highly toxic at elevated concentrations. Photoautotrophic microbes hold promise for heavy metal bioremediation applications because of their ease of culture and their ability to produce sulfide through metabolic processes that in turn are known to complex with the metal ion, Hg(II). The green alga Chlamydomonas reinhardtii, the red alga Cyanidioschyzon merolae, and the cyanobacterium Synechococcus leopoliensis were all able to synthesize sulfide and form zinc sulfide when exposed to Zn(II). Supplementation of their respective media with sulfite and cysteine had deleterious effects on growth, although ZnS still formed in Cyanidioschyzon cells to the same extent as in unsupplemented cells. The simultaneous addition of sulfate and Zn(II) had similar effects to that of Zn(II) alone in all three species, whereas supplying sulfate prior to exposure to Zn(II) enhanced metal sulfide production. The coupled activities of serine acetyltransferase and O-acetylserine(thiol)lyase (SAT/OASTL) did not increase significantly in response to conditions in which enhanced ZnS formation occurred; sulfate added prior to and simultaneously with Zn(II). However, even low activity could provide sufficient sulfate assimilation over this relatively long-term study. Because the extractable activity of cysteine desulfhydrase was elevated in cells that produced higher amounts of zinc sulfide, cysteine is the probable source of the sulfide in this aerobic process. 相似文献