195,996 research outputs found
Inheritance of Suri and Huacaya type of fleece in Alpaca
No full textBackground
Genetic improvement of fibre-producing animal species has often induced transition from double coated to single coated fleece, accompanied by dramatic changes in skin follicles and hair composition, likely implying variation at multiple loci. Huacaya, the more common fleece phenotype in alpaca (Vicugna pacos), is characterized by a thick dense coat growing perpendicularly from the body, whereas the alternative rare and more prized single-coated Suri phenotype is distinguished by long silky fiber that
grows parallel to the body and hangs in separate, distinctive pencil locks. A singlelocus genetic model has been proposed for the Suri-Huacaya phenotype, where Huacaya is recessive.
Methods
Two reciprocal experimental test-crosses (Suri x Huacaya) were carried out, involving a total of 17 unrelated males and 149 unrelated females. An additional dataset of 587
offspring of Suri x Suri crosses was analyzed. Segregation ratios, population genotype frequencies, and/or recombination fraction under different genetic models were
estimated by maximum likelihood.
Results
The single locus model for the Suri/Huacaya phenotype is rejected. In addition, we present two unexpected observations: 1) a large proportion (about 3⁄4) of the Suri
animals is hybrid (with at least one Huacaya offspring), even in rearing conditions where the Huacaya trait would have been almost eliminated; 2) a model with two different values of the segregation ratio fit the data significantly better than a model with a single parameter
Motility and recovery of alpaca (Vicugna pacos) spermatozoa after centrifugation in a density gradient solution
No full textBackground: One of the factors limiting successful processing of alpaca (Vicugna pacos) semen is the viscosity of seminal plasma. The viscous nature of the collected ejaculate has hindered sperm cryopreservation as well as artificial insemination (AI) under field conditions. Aims: The objective of this investigation was to evaluate recovery, motility, and plasma membrane integrity of alpaca spermatozoa after centrifugation in one of two different solutions at one of three different combinations of speed and time. Methods: A total of 24 ejaculates was recovered from seven reproductively sound Huacaya males using a modified artificial vagina (AV) after training the animals for semen collection. A 2 × 3 factorial treatment arrangement was utilized for this study. Ejaculates were divided into fractions for centrifugation in one of two solutions (Tris extender or PureSperm®80 density gradient solution) at one of three combinations of speed and time (492 × g for 15 min, 1968 × g for 10 min, or 4448 × g for 7 min). The experiment was replicated eight times. Results: Analysis revealed that centrifugation at 4448 × g for 7 min in PureSperm®80 provided a high recovery rate of spermatozoa with the highest sperm motility and functional integrity of plasma membrane post-centrifugation. Conclusion: Results suggest that adoption of this procedure (centrifugation at 4448 × g for 7 min in PureSperm®80) in the initial processing of alpaca ejaculates may enhance subsequent ability to use semen for AI and other assisted reproductive biotechnologies in this speciesFil: Gómez Quispe, O. E.. Universidad Nacional Agraria La Molina; Perú. Universidad Nacional Micaela Bastidas de Apurímac; PerúFil: Gutiérrez Reynoso, G. A.. Universidad Nacional Agraria La Molina; PerúFil: Gallegos Cardenas, A.. Universidad Nacional Agraria La Molina; PerúFil: Fumuso, Fernanda Gabriela. Universidad de Buenos Aires. Facultad de Ciencias Veterinarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Asparrin, M.. Fundo Mallkini de Michael & Cia S.A.; PerúFil: Asparrin Del Carpio, M.. Fundo Mallkini de Michael & Cia S.A.; PerúFil: Jara, C. W.. Fundo Mallkini de Michael & Cia S.A.; PerúFil: Ponce, D.. Vivanco International SAC; PerúFil: Miguel, M.. Vivanco International SAC; PerúFil: Youngs, C. R.. Iowa State University; Estados UnidosFil: Vivanco, H. W.. Vivanco International SAC; Per
Suri/Huacaya phenotype inheritance in alpaca (Vicugna pacos)
No full textThe Suri/Huacaya phenotype inheritance in alpaca was tested on rwo indipendent Peruvian sources of records: the Registry of Mallkin farm (588 offspring by Suri sire x Suri dam from 62 paternal half sib families, and 2,126 offspring by Huacaya sire x Huacaya dam froom 177 paternal half sib families) and the results of the Quimsachata INIA ILPA Puno experimental trial (two reciprocal experimental test-crosses, involving a total of 17 unrelated males and 149 unrelated females). The data support a genetic model in which two linked loci must simultaneously be homozigous for recessive alleles in order to produce Huacaya phenotype. The estimated recombination rate between these loci was 0.099 (95%C.L. =0.029-0.204). The Birth of 3 Suri offspring from Huacaya x Huacaya mating is explained by a new mutation on some germinal lines of Huacaya animals. The direct mutation can be estimated at 0.001
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
Intern experience at CH���M Hill, Inc.: an internship report
No full textIncludes author's vita"Submitted to the College of Engineering of Texas A&M University in partial
fulfillment of the requirement for the degree of Doctor of Engineering."Includes bibliographical referencesA review of the author's internship experience with CH���M HILL, Inc.
during the period September 1975 through May 1976 is presented. During this nine month
internship the author worked as an Engineer II in the Industrial Processes discipline of this
large consulting engineering firm... The author's prime responsibility was as one of three
lead design engineers on the design of a large wastewater treatment facility for a pulp mill
in Hoquiam, Washington owned by ITT Rayonier Inc. The work generally consisted of the design
of individual treatment units and associated piping and pumping. The purpose of the project
was to provide wastewater treatment capabilities that would satisfy the effluent limitations
(standards) imposed upon the mill by the State of Washington Department of Ecology and the
U.S. Environmental Protection Agency. The author's assignment also entailed necessary
interaction with the project manager and other CH���M HILL design engineers and support staff
members, the client's representatives, and representatives of two other consulting engineering
firms working on the project. Thus, the internship position at CH���M HILL provided considerable
experience coordinating the author's work with the work of other engineers, guiding the design
and administrative efforts of a support staff, and interacting regularly with the client and
other consulting firms. This broad exposure to a variety of engineering and organizational
problems provided a valuable educational experience
Transition to turbulence in a qblique shock-wave/boundary-layer interaction at M=15
No full textDirect numerical simulations are carried out for different forcing techniques to trigger transition during the interaction between an oblique shock-wave and a laminar boundary-layer at M = 1.5. Three forcing methods are used: a) forcing of oblique unstable modes, whose shape and behaviour are determined by the local linear stability theory, b) broadband free-stream acoustic disturbances, and c) a cold plasma flow control device. While the oblique-mode breakdown is dominant for low-amplitude forcing, long streaky structures drive the transition process in a high-amplitude disturbance environment. LES are also performed on the experimental setup by the Institute of Theoretical and Applied Mechanics (ITAM) from Novosibirsk State University with cold plasma actuation. As well as the disturbance type, the effect of Reynolds number and forcing amplitude will be investigated
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