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341.
Sébastien Villotte Dominique Castex Vincent Couallier Olivier Dutour Christopher J. Knüsel Dominique Henry‐Gambier 《American journal of physical anthropology》2010,142(2):224-234
Enthesopathies—that is, “musculo‐skeletal stress markers”—are frequently used to reconstruct past lifestyles and activity patterns. Relatively little attention has been paid in physical anthropology to methodological gaps implicit in this approach: almost all methods previously employed neglect current medical insights into enthesopathies and the distinction between healthy and pathological aspects has been arbitrary. This study presents a new visual method of studying fibrocartilaginous enthesopathies of the upper limb (modified from Villotte: Bull Mém Soc Anthropol Paris n.s. 18 (2006) 65–85), and application of this method to 367 males who died between the 18th and 20th centuries, from four European identified skeletal collections: the Christ Church Spitalfields Collection, the identified skeletal collection of the anthropological museum of the University of Coimbra, and the Sassari and Bologna collections of the museum of Anthropology, University of Bologna. The analysis, using generalized estimating equations to model repeated binary outcome variables, has established a strong link between enthesopathies and physical activity: men with occupations involving heavy manual tasks have significantly (P‐value < 0.001) more lesions of the upper limbs than nonmanual and light manual workers. Probability of the presence of an enthesopathy also increases with age and is higher for the right side compared with the left. Our study failed to distinguish significant differences between the collections when adjusted for the other effects. It appears that enthesopathies can be used to reconstruct past lifestyles of populations if physical anthropologists: 1) pay attention to the choice of entheses in their studies and 2) use appropriate methods. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
342.
Lori A. Biederman Sydney M. Weldon Derek S. Anderson Mark J. Leoschke 《Ecology and evolution》2020,10(17):9532-9537
The western fringed prairie orchid (WFPO) is a rare plant found in mesic to wet tallgrass prairies in the Great Plains and Midwest regions of the United States. The size of WFPO populations varies considerably from year to year, and studies have suggested that population size is dependent on precipitation during critical periods in the plant's annual development. We hypothesized that plant height and reproductive effort would also be controlled by precipitation, either during these periods or over a broader period. We acquired available images of WFPO from 21 herbaria, and of these 141 individual plants had information adequate for analysis, although some population/year combinations were represented multiple times. For each specimen, we measured plant height (cm) and reproductive effort (as measured by total flower and bud count). We used bootstrapped linear regression, randomly selecting one individual from each population/year combination, to compare precipitation models, both during critical periods and the various summaries. We found that precipitation during the phenologically critical periods was a poor predictor of plant height and reproductive effort. Of the broader precipitation variables, accumulated precipitation from January 1 to collection date best described plant height. We also used correlations to detect a relationship among the variables WFPO height, reproductive effort, precipitation, latitude, and year of collection. Year of specimen collection was negatively correlated with WFPO plant height and accumulated precipitation, suggesting that both have declined in more recent years. Negative correlations with latitude also suggest height and precipitation decrease in the northern part of WFPO's range. Reproductive effort was not related to tested precipitation variables; however, it was weakly correlated with plant height. Although the results are limited, this study leverages available data and makes inferences on WFPO biology over broad ranges of time (1894–2012) and latitude (37.5°–49.9°). 相似文献
343.
Movement of Aedes aegypti following a sugar meal and its implication in the development of control strategies in Durán,Ecuador
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Whitney A. Qualls Diana P. Naranjo Miguel Angel Subía Giovanni Ramon Varsovia Cevallos Isabel Grijalva Eduardo Gómez Kristopher L. Arheart Douglas O. Fuller John C. Beier 《Journal of vector ecology》2016,41(2):224-231
We evaluated how the presence of sugar sources impacted the distribution of Aedes aegypti in different habitats in Durán , Ecuador. Land cover and normalized difference vegetation index maps were used to guide a random point sampling routine to select study grids (30 m × 30 m) in low vegetation (LV) and high vegetation (HV). Five individual plants, at one home in the LV and HV grid, were treated with a different colored, non‐attractive, 60% sucrose solution to determine mosquito feeding and movement. Sugar alone is not attractive to mosquitoes, so spraying vegetation with a dyed sugar solution can be used for visual determination of sugar feeding. Outdoor collections using BG sentinel traps and indoor collections using aspirators were conducted at the treatment home and with collection points at 20, 40, and 60 m surrounding the treatment home for three consecutive days. A total of 3,245 mosquitoes in two genera, Aedes and Culex, was collected. The proportion of stained Ae. aegypti females was 56.8% (510/898) and 0% for males. For Culex, 63.9% (248/388) females and 36.1% (140/388) males were collected stained. Aedes aegypti and Culex spp. were found up to 60 m stained in both LV and HV grids. Significantly more stained females Ae. aegypti were found inside homes compared to females and males of Culex spp. in both habitats. This study identifies that outdoor sugar feeding is a common behavior of Ae. aegypti and can be targeted as a control strategy in urban habitats in Latin America. 相似文献
344.
Strengths and weaknesses of museum and national survey data sets for predicting regional species richness: comparative and combined approaches 总被引:1,自引:1,他引:0
We compiled three independent data sets of bird species occurrences in northeastern Colorado to test how predicted species richness compared to a combined analysis using all the data. The first data set was a georeferenced regional museum data set from two major repositories — the Denver Museum of Nature, and the Science and University of Colorado Museum. The two national survey data sets were the Breeding Bird Survey (summer), and the Great Backyard Bird Count (winter). Resulting analyses show that the museum data sets give richness estimates closest to the combined data set while exhibiting a skewed abundance distribution, whereas survey data sets do not accurately estimate overall richness even though they contain far more records. The combined data set allows the strengths of one data set to augment weaknesses in others. It is likely some museum data sets display skewed abundance distributions due to collectors’ potentially self‐selecting under‐represented species over common ones. 相似文献
345.
DNA stabilization and amplification from museum collections of extracts originally intended for allozyme analysis 总被引:1,自引:0,他引:1
Protein extracts originally prepared for isozyme electrophoresis two decades ago contain surviving DNA sequences susceptible to amplification by the polymerase chain reaction (PCR). Amplification was also possible after stabilization of such extracts on filter paper and immersion under mineral oil without refrigeration. 相似文献
346.
Ting Hui Ng Phiraphol Chusongsang Yupa Chusongsang Somsak Panha 《Molluscan research.》2019,39(2):140-147
ABSTRACTFour decades after its publication, Rolf A.M. Brandt’s 1974 monograph on the non-marine molluscs of Thailand remains the main authority on freshwater and estuarine species for Southeast Asia and includes up to 165 new species of snails and bivalves described by Brandt and colleagues in the same book and preceding publications. All the holotypes are lodged at the Forschungsinstitut und Naturmuseum Senckenberg in Germany, and are largely inaccessible to Thai and other Southeast Asian researchers, who rely heavily on the Brandt collection as a key reference. Paratypes were, however, donated to various other collections, including some in Thailand. We present the first catalogue of 45 paratypes of gastropods of the Brandt collection, described from Thailand, Laos and Cambodia, which are lodged at the Faculty of Tropical Medicine, Mahidol University, Thailand. 相似文献
347.
L. M. Hernández‐Triana S. W. Prosser M. A. Rodríguez‐Perez L. G. Chaverri P. D. N. Hebert T. Ryan Gregory 《Molecular ecology resources》2014,14(3):508-518
In this study, we evaluated the efficacy of various primers for the purpose of DNA barcoding old, pinned museum specimens of blackflies (Diptera: Simuliidae). We analysed 271 pinned specimens representing two genera and at least 36 species. Due to the age of our material, we targeted overlapping DNA fragments ranging in size from 94 to 407 bp. We were able to recover valid sequences from 215 specimens, of which 18% had 500‐ to 658‐bp barcodes, 36% had 201‐ to 499‐bp barcodes and 46% had 65‐ to 200‐bp barcodes. Our study demonstrates the importance of choosing suitable primers when dealing with older specimens and shows that even very short sequences can be diagnostically informative provided that an appropriate gene region is used. Our study also highlights the lack of knowledge surrounding blackfly taxonomy, and we briefly discuss the need for further phylogenetic studies in this socioeconomically important family of insects. 相似文献
348.
Auditory exostoses have been included in craniological investigations since the last century and recently comprised among
epigenetic traits. There is general agreement on the importance of environmental and behavioural factors on the expression
of these bony formations, in particular habitual diving and swimming in cold water.
The present study contributes new data to our knowledge of the world frequency of this character. Cranial series from New
Guinea and Melanesia (139 skulls), Australia (36) and, for the first time, South Africa (123, from Bushmen, Hottentots and
other ethnic groups) were analysed. While the character is absent in the African series — possibly due to environmental factors
— the frequency of exostoses varies from 4.0 to 4.7% in the other skull collections, mainly belonging to coastal populations.
When the frequency distribution of this pathology is considered in a world context and subdivided according to frequency classes,
a direct relation between occurrence and environmental factors is confirmed. Nevertheless, the widespread distribution of
low frequencies (0.1–3.0%) cannot be solely attributed to the action of cold water, but appears to be the result of different
kinds of stresses or ear pathologies. 相似文献