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91.
Glen R. Hood Thomas H. Q. Powell Meredith M. Doellman Sheina B. Sim Mary Glover Wee L. Yee Robert B. Goughnour Monte Mattsson Dietmar Schwarz Jeffrey L. Feder 《Evolution; international journal of organic evolution》2020,74(1):156-168
Ecological speciation via host-shifting is often invoked as a mechanism for insect diversification, but the relative importance of this process is poorly understood. The shift of Rhagoletis pomonella in the 1850s from the native downy hawthorn, Crataegus mollis, to introduced apple, Malus pumila, is a classic example of sympatric host race formation, a hypothesized early stage of ecological speciation. The accidental human-mediated introduction of R. pomonella into the Pacific Northwest (PNW) in the late 1970s allows us to investigate how novel ecological opportunities may trigger divergent adaptation and host race formation on a rapid timescale. Since the introduction, the fly has spread in the PNW, where in addition to apple, it now infests native black hawthorn, Crataegus douglasii, and introduced ornamental hawthorn, Crataegus monogyna. We use this “natural experiment” to test for genetic differentiation among apple, black, and ornamental hawthorn flies co-occurring at three sympatric sites. We report evidence that populations of all three host-associations are genetically differentiated at the local level, indicating that partial reproductive isolation has evolved in this novel habitat. Our results suggest that conditions suitable for initiating host-associated divergence may be common in nature, allowing for the rapid evolution of new host races when ecological opportunity arises. 相似文献
92.
Joseph F. Boland Charles C. Chung David Roberson Jason Mitchell Xijun Zhang Kate M. Im Ji He Stephen J. Chanock Meredith Yeager Michael Dean 《Human genetics》2013,132(10):1153-1163
We assessed the performance of the new Life Technologies Proton sequencer by comparing whole-exome sequence data in a Centre d’Etude du Polymorphisme Humain trio (family 1463) to the Illumina HiSeq instrument. To simulate a typical user’s results, we utilized the standard capture, alignment and variant calling methods specific to each platform. We restricted data analysis to include the capture region common to both methods. The Proton produced high quality data at a comparable average depth and read length, and the Ion Reporter variant caller identified 96 % of single nucleotide polymorphisms (SNPs) detected by the HiSeq and GATK pipeline. However, only 40 % of small insertion and deletion variants (indels) were identified by both methods. Usage of the trio structure and segregation of platform-specific alleles supported this result. Further comparison of the trio data with Complete Genomics sequence data and Illumina SNP microarray genotypes documented high concordance and accurate SNP genotyping of both Proton and Illumina platforms. However, our study underscored the problem of accurate detection of indels for both the Proton and HiSeq platforms. 相似文献
93.
Kevin A. Whitehead 《Ethnic and racial studies》2013,36(7):1248-1265
The anti-apartheid struggle was characterized by tensions between the opposing ideologies of non-racialism (exemplified by the Freedom Charter) and racialism (exemplified by Black Consciousness). These tensions have remained prevalent in public policies and discourse, and in the writings of social scientists, in the post-apartheid period. In this paper I examine some ways in which issues of whether, when, and how race matters become visible in everyday interactions in South Africa, and what insights this may offer with respect to these ongoing tensions. Specifically, I employ an ethnomethodological, conversation analytic approach to examine some ways in which racial categories are treated as resources for action or constraints on action. I conclude by arguing that these findings point to the contingent and situational operation of a practical non-racialism (as well as practical racialism), and thus to the achievement of these ideologies in the moment-by-moment unfolding of interactions. 相似文献
94.
95.
Gregory M. Kohn Andrew P. King Uwe Pott Meredith J. West 《Ethology : formerly Zeitschrift fur Tierpsychologie》2013,119(6):511-521
The ability to engage others in close proximity may be an essential component of social life and shapes the development of social skills. Variation in the willingness to initiate and sustain close interaction with conspecifics is known as sociability. The Brown‐headed Cowbird (Molothrus ater) uses an affiliative display called the head‐down to bring individuals into close proximity. During fall 2009, we manipulated a large flock of cowbirds in a fission–fusion perturbation and recorded the frequency of head‐downs and social approaches. During the fission–fusion perturbation, the rate of head‐downs remained both correlated and repeatable across perturbations. In spring 2010, we separated individuals into three aviaries, a high, intermediate, and low aviary, based on the frequency of head‐down displays they initiated during the previous fall 2009. When breeding, males in the high flock produced a higher number of songs within counter‐singing matches, and females laid more eggs in comparison with the other aviaries. These findings suggest that head‐down displays performed outside the breeding season may contribute to the development and maintenance of reproductive competence by providing intimate social interactions with others. 相似文献
96.
Nicolene Lottering Donna M. MacGregor Matthew Meredith Clair L. Alston Laura S. Gregory 《American journal of physical anthropology》2013,150(3):386-399
Despite the prominent use of the Suchey–Brooks (S–B) method of age estimation in forensic anthropological practice, it is subject to intrinsic limitations, with reports of differential interpopulation error rates between geographical locations. This study assessed the accuracy of the S–B method to a contemporary adult population in Queensland, Australia and provides robust age parameters calibrated for our population. Three‐dimensional surface reconstructions were generated from computed tomography scans of the pubic symphysis of male and female Caucasian individuals aged 15–70 years (n = 195) in Amira® and Rapidform®. Error was analyzed on the basis of bias, inaccuracy and percentage correct classification for left and right symphyseal surfaces. Application of transition analysis and Chi‐square statistics demonstrated 63.9 and 69.7% correct age classification associated with the left symphyseal surface of Australian males and females, respectively, using the S–B method. Using Bayesian statistics, probability density distributions for each S–B phase were calculated, providing refined age parameters for our population. Mean inaccuracies of 6.77 (±2.76) and 8.28 (±4.41) years were reported for the left surfaces of males and females, respectively; with positive biases for younger individuals (<55 years) and negative biases in older individuals. Significant sexual dimorphism in the application of the S–B method was observed; and asymmetry in phase classification of the pubic symphysis was a frequent phenomenon. These results recommend that the S–B method should be applied with caution in medico‐legal death investigations of Queensland skeletal remains and warrant further investigation of reliable age estimation techniques. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
97.
Meredith?L. Carpenter Jason?D. Buenrostro Cristina Valdiosera Hannes Schroeder Morten?E. Allentoft Martin Sikora Morten Rasmussen Simon Gravel Sonia Guillén Georgi Nekhrizov Krasimir Leshtakov Diana Dimitrova Nikola Theodossiev Davide Pettener Donata Luiselli Karla Sandoval Andrés Moreno-Estrada Yingrui Li Jun Wang M.?Thomas?P. Gilbert Eske Willerslev William?J. Greenleaf Carlos?D. Bustamante 《American journal of human genetics》2013,93(5):852-864
Most ancient specimens contain very low levels of endogenous DNA, precluding the shotgun sequencing of many interesting samples because of cost. Ancient DNA (aDNA) libraries often contain <1% endogenous DNA, with the majority of sequencing capacity taken up by environmental DNA. Here we present a capture-based method for enriching the endogenous component of aDNA sequencing libraries. By using biotinylated RNA baits transcribed from genomic DNA libraries, we are able to capture DNA fragments from across the human genome. We demonstrate this method on libraries created from four Iron Age and Bronze Age human teeth from Bulgaria, as well as bone samples from seven Peruvian mummies and a Bronze Age hair sample from Denmark. Prior to capture, shotgun sequencing of these libraries yielded an average of 1.2% of reads mapping to the human genome (including duplicates). After capture, this fraction increased substantially, with up to 59% of reads mapped to human and enrichment ranging from 6- to 159-fold. Furthermore, we maintained coverage of the majority of regions sequenced in the precapture library. Intersection with the 1000 Genomes Project reference panel yielded an average of 50,723 SNPs (range 3,062–147,243) for the postcapture libraries sequenced with 1 million reads, compared with 13,280 SNPs (range 217–73,266) for the precapture libraries, increasing resolution in population genetic analyses. Our whole-genome capture approach makes it less costly to sequence aDNA from specimens containing very low levels of endogenous DNA, enabling the analysis of larger numbers of samples. 相似文献
98.
Ivar M. McDonald Robert A. Mate F. Christopher Zusi Hong Huang Debra J. Post-Munson Meredith A. Ferrante Lizbeth Gallagher Robert L. Bertekap Ronald J. Knox Barbara J. Robertson David G. Harden Daniel G. Morgan Nicholas J. Lodge Steven I. Dworetzky Richard E. Olson John E. Macor 《Bioorganic & medicinal chemistry letters》2013,23(6):1684-1688
High throughput screening led to the identification of a novel series of quinolone α7 nicotinic acetylcholine receptor (nAChR) agonists. Optimization of an HTS hit (1) led to 4-phenyl-1-(quinuclidin-3-ylmethyl)quinolin-2(1H)-one, which was found to be potent and selective. Poor brain penetrance in this series was attributed to transporter-mediated efflux, which was in turn due to high pKa. A novel 4-fluoroquinuclidine significantly lowered the pKa of the quinuclidine moiety, reducing efflux as measured by a Caco-2 assay. 相似文献
99.
David R. Bauman Alan Whitehead Lisa C. Contino Jisong Cui Margarita Garcia-Calvo Xin Gu Nancy Kevin Xiuying Ma Lee-yuh Pai Kashmira Shah Xiaolan Shen Sloan Stribling Hratch J. Zokian Joe Metzger Diane E. Shevell Sherman T. Waddell 《Bioorganic & medicinal chemistry letters》2013,23(12):3650-3653
In an effort to understand the origin of blood-pressure lowering effects observed in recent clinical trials with 11β-HSD1 inhibitors, we examined a set of 11β-HSD1 inhibitors in a series of relevant in vitro and in vivo assays. Select 11β-HSD1 inhibitors reduced blood pressure in our preclinical models but most or all of the blood pressure lowering may be mediated by a 11β-HSD1 independent pathway. 相似文献
100.
Xiaozhou He Yilin Yang Feng Zhi Meredith L. Moore Xuezhi Kang Dongman Chao Rong Wang Gianfranco Balboni Severo Salvadori Dong H. Kim Ying Xia 《PloS one》2013,8(4)
Hypoxic/ischemic injury to kidney is a frequently encountered clinical problem with limited therapeutic options. Since microRNAs are differentially involved in hypoxic/ischemic events and δ-opioid receptor (DOR) activation is known to protect against hypoxic/ischemic injury, we speculated on the involvement of DOR activation in altering the microRNA (miRNA) expression in kidney under hypoxic condition. We selected 31 miRNAs based on microarray data for quantitative PCR analysis. Among them, 14 miRNAs were significantly altered after prolonged hypoxia, DOR activation or a combination of both. We found that 1) DOR activation alters miRNA expression profiles in normoxic conditions; 2) hypoxia differentially alters miRNA expression depending on the duration of hypoxia; and 3) DOR activation can modify hypoxia-induced changes in miRNA expression. For example, 10-day hypoxia reduced the level of miR-212 by over 70%, while DOR activation could mimic such reduction even in normoxic kidney. In contrast, the same stress increased miR-29a by >100%, which was reversed following DOR activation. These first data suggest that hypoxia comprehensively modifies the miRNA profile within the kidney, which can be mimicked or modified by DOR activation. Ascertaining the targeted pathways that regulate the diverse cellular and molecular functions of miRNA may provide new insights into potential therapies for hypoxic/ischemic injury of the kidney. 相似文献