196,166 research outputs found
Urinary volatile molecules vary in males of the 2 european subspecies of the house mouse and their hybrids
No full textMice recognize other mice by identifying chemicals that confer a molecular signature to urinary marks. Such molecules may be
involved in species recognition, and previous behavioral studies have related divergence of sexual preference between 2 subspecies
of the house mouse (Mus musculus musculus and Mus musculus domesticus) to urinary odors. To characterize the differences
between odors of males of the 2 subspecies and their first-generation offspring, the urinary volatile molecules were examined via
gas chromatography coupled to mass spectrometry. Seven molecules were present in the samples from mice of at least one group.
Their quantity varied among groups: M. m. domesticus showed a quantitatively richer panel of odorants in their urine when
compared with M. m. musculus. The hybrids showed a more complex picture that was not directly related to one or the other
parental subspecies. These quantitative differences may contribute to the specificity of the odorant bouquet of the 2 subspecies
Females of two subspecies of mice differ in their urinary volatile profile
No full textMice recognize other mice by identifying chemicals that confer a molecular signature to urinary marks. Such molecules may be involved in species recognition, and previous behavioral studies have related divergence of sexual preference between 2 subspecies of the house mouse (Mus musculus musculus and Mus musculus domesticus) to urinary odors
Variation in Wolbachia cidB gene, but not cidA, is associated with cytoplasmic incompatibility mod phenotype diversity in Culex pipiens
No full textEndosymbiotic Wolbachia bacteria are, to date, considered the most widespread symbionts in arthropods and are the cornerstone of major biological control strategies. Such a high prevalence is based on the ability of Wolbachia to manipulate their hosts' reproduction. One manipulation called cytoplasmic incompatibility (CI) is based on the death of the embryos generated by crosses between infected males and uninfected females or between individuals infected with incompatible Wolbachia strains. CI can be seen as a modification-rescue system (or mod-resc) in which paternal Wolbachia produce mod factors, inducing embryonic defects, unless the maternal Wolbachia produce compatible resc factors. Transgenic experiments in Drosophila melanogaster and Saccharomyces cerevisiae converged towards a model where the cidB Wolbachia gene is involved in the mod function while cidA is involved in the resc function. However, as cidA expression in Drosophila males was required to observe CI, it has been proposed that cidA could be involved in both resc and mod functions. A recent correlative study in natural Culex pipiens mosquito populations has revealed an association between specific cidA and cidB variations and changes in mod phenotype, also suggesting a role for both these genes in mod diversity. Here, by studying cidA and cidB genomic repertoires of individuals from newly sampled natural C. pipiens populations harbouring wPipIV strains from North Italy, we reinforce the link between cidB variation and mod phenotype variation fostering the involvement of cidB in the mod phenotype diversity. However, no association between any cidA variants or combination of cidA variants and mod phenotype variation was observed. Taken together our results in natural C. pipiens populations do not support the involvement of cidA in mod phenotype variation
The genetic architecture of chemosensory cues involved in species recognition: a behavioral approach in the house mouse.
No full textInternational audienceThe genetics of chemical signals is poorly understood. We addressed this issue in two subspecies of mice, Mus musculus musculus and M. m. domesticus, comparing their odor phenotypes with that of their hybrids. Earlier studies indicated that these subspecies could be discriminated on the basis of their urinary odor. We assessed male odor phenotypes from perception of musculus mice acting as olfactometers. Our results point to a complex genetic determinism. Reciprocal F1 hybrids produced a distinct odor phenotype, with shared characteristics distinguishing them from their parents, and stronger similarity to domesticus than to musculus. These results are consistent with implications of genes with partial dominance and a parent of origin effect. Further, similarities between reciprocal F2 allowed us to reject a direct role of the Y-chromosome in shaping the odor phenotype. However we show that the X-chromosome could be involved in explaining domesticus phenotype, while epistasis between genes on the sex chromosomes and the autosomes might influence musculus phenotype
L’enceinte protohistorique de l’Estey du large. Site archéologique sublacustre du lac de Sanguinet
No full textThe sublacustrian village of l'Estey du large is located 2,5 kilometers from the Eastern extremity of the lake of Sanguinet (Landes), on the left bank of the submerged river-bed of la Gourgue, at an average dephth of 7 m (14 m NGF). A 10% or so gradient permits to go down to the bed of the river.
The site of l'Estey du large is a vast elliptical area of more than 3,000 square metres. Facing the river, an enormous number of tree-trunks are arranged. This wood-work surrounds the wole site and constitutes a solid foundation for the two rows of stakes delimiting the double stockade wich protected the habitat site. The dwellings were integrated into the fortifications.
There is an abundance of ceramic artefacts typical of the end of the Iron Age, whereas metallic artefacts are rare. A dozen spring fibulae have been found as well as two Gaulish coins wich can be dated from the first century B.C.Le village sublacustre de l'Estey du large est situé à 2,500 km de l'extrémité est du lac de Sanguinet (Landes), sur la rive gauche du lit ennoyé de la Gourgue, à une profondeur moyenne de 7 mètres (14 m NGF). Une pente d'environ 10% permet d'atteindre le lit de la rivière en contrebas.
Le site de l'Estey du large se présente comme un vaste espace elliptique de plus de 3000 m². Face à la rivière, on rencontre une importante concentration de troncs ordonnés. Cet ouvrage de bois se poursuit sur toute la périphérie du site, constituant une assise solide pour les deux rangées de pieux marquant le tracé de la double palissade qui protégeait l'habitat. Les habitations étaient intégrées à l'ouvrage de défense.
Le mobilier de céramique caractéristique de la fin de l'âge du fer est abondant. Les objets métalliques sont rares. Une douzaine de fibules à ressort ont été mise au jour ainsi que deux monnaies gauloises datables au milieu du Ier siècle avant Jésus-Christ.Dubos Bernard, Maurin Bernard, Lalanne René. L’enceinte protohistorique de l’Estey du large. Site archéologique sublacustre du lac de Sanguinet. In: Aquitania : une revue inter-régionale d'archéologie, tome 15, 1997. pp. 73-107
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
Simulation of thermal plant optimization and hydraulic aspects of thermal distribution loops for large campuses
No full textFollowing an introduction, the author describes Texas A&M University and its utilities system. After that, the author presents how to construct simulation models for chilled water and heating hot water distribution systems. The simulation model was used in a $2.3 million Ross Street chilled water pipe replacement project at Texas A&M University. A second project conducted at the University of Texas at San Antonio was used as an example to demonstrate how to identify and design an optimal distribution system by using a simulation model. The author found that the minor losses of these closed loop thermal distribution systems are significantly higher than potable water distribution systems. In the second part of the report, the author presents the latest development of software called the Plant Optimization Program, which can simulate cogeneration plant operation, estimate its operation cost and provide optimized operation suggestions. The author also developed detailed simulation models for a gas turbine and heat recovery steam generator and identified significant potential savings. Finally, the author also used a steam turbine as an example to present a multi-regression method on constructing simulation models by using basic statistics and optimization algorithms. This report presents a survey of the author??s working experience at the Energy Systems Laboratory (ESL) at Texas A&M University during the period of January 2002 through March 2004. The purpose of the above work was to allow the author to become familiar with the practice of engineering. The result is that the author knows how to complete a project from start to finish and understands how both technical and nontechnical aspects of a project need to be considered in order to ensure a quality deliverable and bring a project to successful completion. This report concludes that the objectives of the internship were successfully accomplished and that the requirements for the degree of Degree of Engineering have been satisfied
- …
