Science.gov

Sample records for 4-h livestock projects

  1. The Impact of Raising and Exhibiting Selected 4-H Livestock Projects on the Development of Life and Project Skills.

    ERIC Educational Resources Information Center

    Rusk, Clinton P.; Summerlot-Early, Jill M.; Machtmes, Krisanna L.; Talbert, B. Allen; Balschweid, Mark A.

    2003-01-01

    Responses from 176 of 420 4-H members involved in livestock projects showed they were able to accomplish skills in sportsmanship, safety, and animal grooming and selection but were less confident about animal health care. The sense of responsibility acquired from these projects was applied to homework, punctuality, and care for younger siblings.…

  2. Development and Evaluation of an On-Line Educational Module for Volunteer Leaders on Bio-Security in Washington State 4-H Livestock Projects

    ERIC Educational Resources Information Center

    Stevenson, Jill L.; Moore, Dale A.; Newman, Jerry; Schmidt, Janet L.; Smith, Sarah M.; Smith, Jean; Kerr, Susan; Wallace, Michael; BoyEs, Pat

    2011-01-01

    An on-line module on disease prevention was created for 4-H volunteer leaders who work with livestock projects in Washington to better prepare them to teach youth about bio-security and its importance in 4-H livestock projects. Evaluation of the module and usage statistics since the module's debut were collected and evaluated. The module increases…

  3. Development and Evaluation of an On-Line Educational Module for Volunteer Leaders on Bio-Security in Washington State 4-H Livestock Projects

    ERIC Educational Resources Information Center

    Stevenson, Jill L.; Moore, Dale A.; Newman, Jerry; Schmidt, Janet L.; Smith, Sarah M.; Smith, Jean; Kerr, Susan; Wallace, Michael; BoyEs, Pat

    2011-01-01

    A module on disease prevention was created for 4-H volunteer leaders who work with livestock projects in Washington to better prepare them to teach youth about bio-security and its importance in 4-H livestock projects. Evaluation of the module and usage statistics since the module's debut were collected and evaluated. The module increases…

  4. Assessing the Need for an On-Line Educational Module for Volunteer Leaders on Bio-Security in Washington State 4-H Livestock Projects

    ERIC Educational Resources Information Center

    Stevenson, Jill L.; Moore, Dale A.; Newman, Jerry; Schmidt, Janet L.; Smith, Sarah M.; Smith, Jean; Kerr, Susan; Wallace, Michael; BoyEs, Pat

    2011-01-01

    4-H livestock projects present disease transmission risks that can be reduced by the use of bio-security practices. The responsibility of teaching bio-security to youth belongs primarily to volunteer leaders, who may not be aware of the importance of these practices. A needs assessment for an online educational module about bio-security revealed…

  5. Perceptions of Texas 4-H Livestock Ambassadors on Career Development, Higher Education, and Leadership Development

    ERIC Educational Resources Information Center

    Zanolini, William F.; Rayfield, John; Ripley, Jeff

    2013-01-01

    Selected 4-H youth participated in the Texas 4-H Livestock Ambassador program. Forty-five youth participated in the 3-day program delivered by university professors and staff, Texas AgriLife Extension faculty and industry representatives. An instrument was developed and administered to the Texas 4-H Livestock Ambassadors at the end of their first…

  6. 4-H Textile Science Textile Arts Projects.

    ERIC Educational Resources Information Center

    Scholl, Jan

    This packet contains three 4-H textile arts projects for students in the textile sciences area. The projects cover weaving, knitting, and crocheting. Each project provides an overview of what the student will learn, what materials are needed, and suggested projects for the area. Projects can be adapted for beginning, intermediate, or advanced…

  7. Separates. 4-H Textile Science Advanced Project.

    ERIC Educational Resources Information Center

    Scholl, Jan F.

    This booklet, which was developed for use by 4-H club members in Pennsylvania, contains the information required to sew a two-piece nontailored outfit and/or a one-or two-piece dress. The following are among the topics covered: the difference between a fiber and a fabric; properties of different fibers and fabrics; common jacket, neckline, sleeve,…

  8. The Big E (Energy). 4-H Energy Project. 4-H Member's E-Book, Unit 1.

    ERIC Educational Resources Information Center

    Caldwell, William; And Others

    This activity and record book is designed for unit 1 (ages 9-11) of the Nebraska 4-H Energy Project. In this project, members are required to: (1) use energy wisely by closing doors and turning off lights; (2) inspecting homes for energy use at least once; (3) judging the best use of lighting in a home; (4) sharing ideas about energy use in a…

  9. Starting and Maintaining a Marine Aquarium: 4-H Members Guide [and] 4-H Member's Project Record Book.

    ERIC Educational Resources Information Center

    Crenshaw, Neil

    The guide and the project record book included in this document are designed for 4-H members who would like to start a salt-water aquarium project. The guide includes the following topics: (1) general requirements for salt-water aquariums; (2) directions for making an aquarium; (3) suggestions for where to locate it; (4) pros and cons of using…

  10. Implementing Livestock Anaerobic Digestion Projects

    EPA Pesticide Factsheets

    Page provides information to help make an informed decision about installing an anaerobic digester. Is it a good match for a farm’s organic waste, project financing, development guidelines and permit requirements?

  11. New Jersey 4-H Marine Science Project. Leaders Guide.

    ERIC Educational Resources Information Center

    Jesuncosky, Betty Jean, Comp.

    This guide contains a collection of activities which are designed to provide opportunities for 4-H voluteers and youth in New Jersey to get involved in learning about the marine environment. The guide is divided into five sections which deal with habitats, organisms, career exploration, community involvement, and additional marine activities. Each…

  12. The 4-H Debate Project: Getting Adults and Children Involved in Communication.

    ERIC Educational Resources Information Center

    Atwater, Deborah F.

    Intended to enhance adult leadership skills, the 4-H Debate Project, developed by the 4-H Communication Committee of Delaware County (Pennsylvania), was designed to (1) increase the members' knowledge of library skills through research, (2) make them aware of current issues, (3) help them to become better public speakers and communicators, (4)…

  13. New Jersey 4-H Goat Extravaganza: Efficiently Meeting the Educational Needs of 4-H Goat Project Members, Volunteers, and Parents

    ERIC Educational Resources Information Center

    Ripberger, Chad

    2014-01-01

    The 4-H Goat Extravaganza maximizes limited resources to help youth and adults develop knowledge and skills in goat care and management. It capitalizes on the talents and interests of volunteers to efficiently combine a goat-themed art show, team presentation contest, quiz bowl, skillathon, and adult workshop into 1 day. This article outlines the…

  14. 4-H Horticulture Project Activity Guides. Leader's Guide and Units 1-3.

    ERIC Educational Resources Information Center

    Illinois Univ., Urbana. Cooperative Extension Service.

    This document, concerning the 4-H horticulture project, includes a leader's guide and three youth activity guides. The leader's guide can be used to plan group project meetings that are both fun and educational. Activities can be adapted to various age groups. The leader's guide includes basic information for growing plants indoors and outdoors,…

  15. Bio-Security Proficiencies Project for Beginning Producers in 4-H

    ERIC Educational Resources Information Center

    Smith, Martin H.; Meehan, Cheryl L.; Borba, John A.

    2014-01-01

    Improving bio-security practices among 4-H members who raise and show project animals is important. Bio-security measures can reduce the risk of disease spread and mitigate potential health and economic risks of disease outbreaks involving animal and zoonotic pathogens. Survey data provided statistical evidence that the Bio-Security Proficiencies…

  16. Children and their 4-H animal projects: How children use science in agricultural activity

    NASA Astrophysics Data System (ADS)

    Emo, Kenneth Roy

    Many children are introduced to science through informal educational programs. 4-H, an educational youth program, has a history of introducing scientific practices into agriculture. The purpose of this ethnographically-driven case study is to examine how science informs the actions of children raising market animals in a 4-H project. For two years the researcher collected data on 4-H children with market animal projects. Observations, interviews, and artifacts gathered are interpreted using the framework of activity theory. This study provides evidence for how the context of an activity system influences individual actions. Rules developed by the organization guide the actions of children to incorporate physical and psychological tools of science into their project to achieve the object: producing animals of proper weight and quality to be competitive in the county fair. Children learn the necessary actions from a community of practitioners through which expertise is distributed. Children's learning is demonstrated by the way their participation in their project changes with time, from receiving assistance from others to developing expertise in which they provide assistance to others. The strength of this educational experience is how children apply specific tools of science in ways that provide meaning and relevancy to their 4-H activity.

  17. [Nebraska 4-H Wheat Science School Enrichment Project, Teacher/Leader Guides 213-222 and 227.

    ERIC Educational Resources Information Center

    Nebraska Univ., Lincoln. Inst. of Agriculture and Natural Resources.

    Through the 4-H Wheat Science project, students learn the importance of wheat from the complete process of growing wheat to the final product of bread. The curriculum is designed to include hands-on experiences in science, consumer education, nutrition, production economics, vocabulary, and applied mathematics. Teachers can select those units out…

  18. Influence of 4-H Horse Project Involvement on Development of Life Skills

    ERIC Educational Resources Information Center

    Anderson, K. P.; Karr-Lilienthal, L.

    2011-01-01

    Four-H horse project members who competed in non-riding horse contests were surveyed to evaluate the influence of their horse project participation on life-skill development. Contests in which youth competed included Horse Bowl, Demonstrations, Public Speaking, and Art. Youth indicated a positive influence on both life-skill development and horse…

  19. A Manual of Mosquito Control Projects and Committee Assignments for 4-H and Scouts Biology Class Projects, Organized Community Service Programs, and Individuals Interested in Environmental Management.

    ERIC Educational Resources Information Center

    Hart, Richard A.

    The mosquito control projects presented in this manual were prepared from an educational viewpoint and are intended for use by students in 4-H and Scouts and as a supplement to high school and college biology course work. The major emphasis of the projects is on integrated pest management, an approach utilizing cost-effective control methods which…

  20. Dog Helper's Guide: Dog Project Group Activities Grades 3-12. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08169

    ERIC Educational Resources Information Center

    National 4-H Council, 2005

    2005-01-01

    This final guide in the series is designed to assist in one's role of helper for youth interested in the dog project. These learn-by-doing activities can be adapted for families, classrooms, dog project meetings, after school programs, camps or other settings. In this Helper's Guide, one will find helpful information about characteristics of…

  1. SOIL AND WATER CONSERVATION PROJECTS AND ACTIVITIES, A GUIDE FOR 4-H CLUB LEADERS.

    ERIC Educational Resources Information Center

    FOSTER, ALBERT B.; FOX, ADRIAN C.

    THIS PUBLICATION WAS PREPARED BY THE SOIL CONSERVATION SERVICE FOR USE WITH YOUTH GROUPS. VARIOUS ACTIVITIES AND PROJECTS ARE PRESENTED WHICH CAN BE USED TO DEVELOP CONCEPTS ABOUT SOIL AND WATER CONSERVATION. IN ORDER TO SIMPLIFY THE PROCESS OF DEMONSTRATING THESE ACTIVITIES, MANY OF THE CONCEPTS ARE PICTORIALLY ILLUSTRATED. THE ACTIVITIES…

  2. Environmentally Sound Small-Scale Livestock Projects. Guidelines for Planning Series Number 5.

    ERIC Educational Resources Information Center

    Jacobs, Linda

    This document was developed in response to the need for simplified technical information for planning environmentally sound small-scale projects in third world countries. It is aimed specifically at those who are planning or managing small-scale livestock projects in less-developed areas of the tropics and sub-tropics. The guidelines included in…

  3. Engaging Library Partners in 4-H Programming

    ERIC Educational Resources Information Center

    Fields, Nia Imani; Rafferty, Elizabeth

    2012-01-01

    When most people think about 4-H, they remember county fairs, livestock programs, and agricultural education. While these programs are still prominent, 4-H has grown in order to meet the growing demands of today's youth. The organization has expanded services and programs to serve rural, suburban, and urban youth in every state in the U.S. 4-H is…

  4. Discover 4-H Clubs: The Essential Resource for 4-H

    ERIC Educational Resources Information Center

    MacArthur, Stacey; Nelson, Cindy; Brower, Naomi; Memmott, Margie; Peterson, Gaelynn

    2016-01-01

    Obstacles facing new 4-H volunteers include time constraints and difficulty finding project-specific information, resources, and opportunities available for club members. As a solution to these obstacles and an aid for assisting volunteers in becoming confident in delivering information to youth, content experts produced Discover 4-H Clubs, a…

  5. 4-H and Iowa.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This issue focuses on Iowa's role in the historical development of the 4-H youth program. "Roots in Iowa" and "Jessie Field Shambaugh: The Mother of 4-H" (J. Friedel) describes the rural Iowan roots of the 4-H program, which today is located in 80 different countries, and give the story of its founder. Jessie Shambaugh, a rural…

  6. Livestock Judging. A Unit for Teachers of Vocational Agriculture. Production Agriculture Curriculum Materials Project.

    ERIC Educational Resources Information Center

    Smith, Anthony

    Designed to provide instructional materials for use by vocational agriculture teachers, this unit on livestock judging contains materials based on five competencies needed to be a livestock producer. The following competencies are covered: general preparation for livestock judging, selection, and evaluation; judging, selection, and evaluation of…

  7. 4-H Club Goat Guide.

    ERIC Educational Resources Information Center

    Brown, R. Kipp

    This guide provides information for 4-H Club members who have decided on a club goat project. Topics include general information in the following areas: show rules; facilities and equipment (barns/sheds, fences, feeders, water containers, and equipment); selection (structural correctness, muscle, volume and capacity, style and balance, and growth…

  8. Feeding Livestock. A Unit for Teachers of Vocational Agriculture. Production Agriculture Curriculum Materials Project.

    ERIC Educational Resources Information Center

    Johnson, Boyd C.

    Designed to provide instructional materials for use by vocational agriculture teachers, this unit on feeding livestock contains nine lessons based upon competencies needed to be a livestock producer. The lessons in this unit cover the importance of good feeding practices, the identification of nutritional needs and the composition of feeds for…

  9. Breeding Livestock. A Unit for Teachers of Vocational Agriculture. Production Agriculture Curriculum Materials Project.

    ERIC Educational Resources Information Center

    O'Bryan, Robert C.

    Designed to provide instructional materials for use by vocational agriculture teachers, this unit on breeding livestock contains materials for use in teaching the importance of breeding, the physiology of livestock breeding, reproductive processes, sire selection, and breeding systems. Lessons on each of these competencies contain the following:…

  10. Strengthening 4-H Program Communication through Technology

    ERIC Educational Resources Information Center

    Robideau, Kari; Santl, Karyn

    2011-01-01

    Advances in technology are transforming how youth and parents interact with programs. The Strengthening 4-H Communication through Technology project was implemented in eight county 4-H programs in Northwest Minnesota. This article outlines the intentional process used to effectively implement technology in program planning. The project includes:…

  11. Final report for the Iowa Livestock Industry Waste Characterization and Methane Recovery Information Dissemination Project

    SciTech Connect

    Garrison, M.V.; Richard, Thomas L

    2001-11-13

    This report summarizes analytical methods, characterizes Iowa livestock wastes, determines fossil fuel displacement by methane use, assesses the market potential, and offers recommendations for the implementation of methane recovery technologies.

  12. Rift Valley fever dynamics in Senegal: a project for pro-active adaptation and improvement of livestock raising management.

    PubMed

    Lafaye, Murielle; Sall, Baba; Ndiaye, Youssou; Vignolles, Cecile; Tourre, Yves M; Borchi, Franc Ois; Soubeyroux, Jean-Michel; Diallo, Mawlouth; Dia, Ibrahima; Ba, Yamar; Faye, Abdoulaye; Ba, Taibou; Ka, Alioune; Ndione, Jacques-André; Gauthier, Hélène; Lacaux, Jean-Pierre

    2013-11-01

    The multi-disciplinary French project "Adaptation à la Fiévre de la Vallée du Rift" (AdaptFVR) has concluded a 10-year constructive interaction between many scientists/partners involved with the Rift Valley fever (RVF) dynamics in Senegal. The three targeted objectives reached were (i) to produce--in near real-time--validated risk maps for parked livestock exposed to RVF mosquitoes/vectors bites; (ii) to assess the impacts on RVF vectors from climate variability at different time-scales including climate change; and (iii) to isolate processes improving local livestock management and animal health. Based on these results, concrete, pro-active adaptive actions were taken on site, which led to the establishment of a RVF early warning system (RVFews). Bulletins were released in a timely fashion during the project, tested and validated in close collaboration with the local populations, i.e. the primary users. Among the strategic, adaptive methods developed, conducted and evaluated in terms of cost/benefit analyses are the larvicide campaigns and the coupled bio-mathematical (hydrological and entomological) model technologies, which are being transferred to the staff of the "Centre de Suivi Ecologique" (CSE) in Dakar during 2013. Based on the results from the AdaptFVR project, other projects with similar conceptual and modelling approaches are currently being implemented, e.g. for urban and rural malaria and dengue in the French Antilles.

  13. Trends and Projected Estimates of GHG Emissions from Indian Livestock in Comparisons with GHG Emissions from World and Developing Countries.

    PubMed

    Patra, Amlan Kumar

    2014-04-01

    This study presents trends and projected estimates of methane and nitrous oxide emissions from livestock of India vis-à-vis world and developing countries over the period 1961 to 2010 estimated based on IPCC guidelines. World enteric methane emission (EME) increased by 54.3% (61.5 to 94.9 ×10(9) kg annually) from the year 1961 to 2010, and the highest annual growth rate (AGR) was noted for goat (2.0%), followed by buffalo (1.57%) and swine (1.53%). Global EME is projected to increase to 120×10(9) kg by 2050. The percentage increase in EME by Indian livestock was greater than world livestock (70.6% vs 54.3%) between the years 1961 to 2010, and AGR was highest for goat (1.91%), followed by buffalo (1.55%), swine (1.28%), sheep (1.25%) and cattle (0.70%). In India, total EME was projected to grow by 18.8×10(9) kg in 2050. Global methane emission from manure (MEM) increased from 6.81 ×10(9) kg in 1961 to 11.4×10(9) kg in 2010 (an increase of 67.6%), and is projected to grow to 15×10(9) kg by 2050. In India, the annual MEM increased from 0.52×10(9) kg to 1.1×10(9) kg (with an AGR of 1.57%) in this period, which could increase to 1.54×10(9) kg in 2050. Nitrous oxide emission from manure in India could be 21.4×10(6) kg in 2050 from 15.3×10(6) kg in 2010. The AGR of global GHG emissions changed a small extent (only 0.11%) from developed countries, but increased drastically (1.23%) for developing countries between the periods of 1961 to 2010. Major contributions to world GHG came from cattle (79.3%), swine (9.57%) and sheep (7.40%), and for developing countries from cattle (68.3%), buffalo (13.7%) and goat (5.4%). The increase of GHG emissions by Indian livestock was less (74% vs 82% over the period of 1961 to 2010) than the developing countries. With this trend, world GHG emissions could reach 3,520×10(9) kg CO2-eq by 2050 due to animal population growth driven by increased demands for meat and dairy products in the world.

  14. Livestock Anaerobic Digester Database

    EPA Pesticide Factsheets

    The Anaerobic Digester Database provides basic information about anaerobic digesters on livestock farms in the United States, organized in Excel spreadsheets. It includes projects that are under construction, operating, or shut down.

  15. Minnesota 4-H Science of Agriculture Challenge: Infusing Agricultural Science and Engineering Concepts into 4-H Youth Development

    ERIC Educational Resources Information Center

    Rice, Joshua E.; Rugg, Bradley; Davis, Sharon

    2016-01-01

    Youth involved in 4-H projects have been engaged in science-related endeavors for years. Since 2006, 4-H has invested considerable resources in the advancement of science learning. The new Minnesota 4-H Science of Agriculture Challenge program challenges 4-H youth to work together to identify agriculture-related issues in their communities and to…

  16. Engaging Latino Youth in Community-Based Programs: Findings from the First Ten Years of the Oregon 4-H Latino Outreach Project

    ERIC Educational Resources Information Center

    Hobbs, Beverly B.; Sawer, Barbara

    2009-01-01

    Community-based educational programs play a significant role in the education and positive development of youth. Over the last decade, the Oregon 4-H Youth Development program has made special efforts to reach and engage Latino youth and families in non-formal educational programs. Latino families most often do not access community-based…

  17. Future Projections from the Effects of Heat Stress on Livestock: for the US and New England Region

    NASA Astrophysics Data System (ADS)

    McCabe, E.; Buzan, J. R.; Huber, M.; Krishnan, S.

    2015-12-01

    Future climate change will result in variations in heat stress experienced by livestock, which will consequently impact health, well-being, and yield. In this study, we estimate future yield changes for livestock due to heat stress in New England. We use the Community Land Model version 4.5 (CLM4.5), a component of the Community Earth System Model (CESM) that is developed by the National Center for Atmospheric Research (NCAR). The simulation uses RCP8.5 boundary conditions, and is driven by CCSM4 atmospheric forcing from the CMIP5 archive, that conducts simulations of the past and next century. Heat stress metrics are calculated using the HumanIndexMod in CLM4.5 for the early and late 21st century. For example, the humidity index for comfort and physiology, wet bulb temperature and swamp cooler efficiency. Results indicate that in the New England Region, temperatures will increase by 4 °C and in New Hampshire specifically by 3 °C. Temperature humidity index for comfort and physiology, swamp cooler efficiency and wet bulb are all projected to rise by the end of the century. While it is obvious that these elevations in temperature will have a negative effect on animals inhibiting their performance and output, our analysis also emphasizes the role of changes in humidity in heat stress. We show that heat stress caused by temperature and humidity increases, will decrease overall production yield for dairy and beef cattle, sows, finishing hogs and poultry, as a result of heat stress and other major climatic factors. We estimate and discuss resulting economic losses for the livestock industries and the impact in the United States and New England Region.

  18. Livestock Marketing.

    ERIC Educational Resources Information Center

    Futrell, Gene; And Others

    This marketing unit focuses on the seasonal and cyclical patterns of livestock markets. Cash marketing, forward contracting, hedging in the futures markets, and the options markets are examined. Examples illustrate how each marketing tool may be useful in gaining a profit on livestock and cutting risk exposure. The unit is organized in the…

  19. Orbivirus of livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Arthropod Borne Animal Diseases Unit (ABADRU) mission is to solve major endemic, emerging, and exotic arthropod-borne disease problems in livestock. The ABADRU has four 5-year project plans under two ARS National Research Programs; Animal Health NP103 and Veterinary, Medical, and Urban Entomolog...

  20. Projected Cropping Patterns, Livestock Enterprises, Processing Activities, Capital Requirements, Employment, Income, and Training Needs for Alternative Farm Organizational Structures for the Navajo Indian Irrigation Project. A Special Report to the Four Corners Regional Commission.

    ERIC Educational Resources Information Center

    Gorman, William D.; And Others

    Information on the expected cropping patterns, livestock enterprises, processing and related activities, income and employment opportunities, capital needs, and training requirements for alternative farm organizational structures that could be selected for development of the Navajo Indian Irrigation Project is presented in this report. The major…

  1. Sewing Skills Progress Chart. 4-H Textile Science.

    ERIC Educational Resources Information Center

    Scholl, Jan F.

    This document, which was developed for use by Pennsylvania 4-H Club leaders and members, is a chart that can be used to help club members determine and document those sewing skills they already have and those they need to learn as they complete one or more 4-H Club sewing projects. The document begins with a note to club leaders and parents that…

  2. Textile Science Leader's Guide. 4-H Textile Science.

    ERIC Educational Resources Information Center

    Scholl, Jan

    This instructor's guide provides an overview of 4-H student project modules in the textile sciences area. The guide includes short notes explaining how to use the project modules, a flowchart chart showing how the project areas are sequenced, a synopsis of the design and content of the modules, and some program planning tips. For each of the…

  3. Developing a Mobile Extension Course for Youth Livestock Producers

    ERIC Educational Resources Information Center

    Weitzenkamp, Deborah; Dam, Karna; Chichester, Lindsay

    2015-01-01

    The 4-H Livestock Quality Assurance course is a mobile Extension course for youth and youth leaders. In 3 years of implementation, over 6,600 participants from 16 states have learned about good production practices for animal agriculture through the innovative online Nebraska Livestock Quality Assurance course. By evaluating the needs of our youth…

  4. Adult 4-H Volunteer Empowerment in 4-H Youth Development Settings

    ERIC Educational Resources Information Center

    Olsen, Pamela

    2009-01-01

    The primary purpose of this study was to determine which factors related to adult 4-H volunteer empowerment in 4-H youth development settings. This study examined the relationship of adult 4-H volunteers' perceived leadership styles of Oregon 4-H Youth Development Educators (YDE) to the adult 4-H volunteer sense of empowerment. In addition,…

  5. Strengthening 4-H by Analyzing Enrollment Data

    ERIC Educational Resources Information Center

    Hamilton, Stephen F.; Northern, Angela; Neff, Robert

    2014-01-01

    The study reported here used data from the ACCESS 4-H Enrollment System to gain insight into strengthening New York State's 4-H programming. Member enrollment lists from 2009 to 2012 were analyzed using Microsoft Excel to determine trends and dropout rates. The descriptive data indicate declining 4-H enrollment in recent years and peak enrollment…

  6. Curtiss JN-4H Towing Model Wing

    NASA Technical Reports Server (NTRS)

    1921-01-01

    In 1919 the NACA Langley laboratory received its first three research aircraft which were Curtiss JN-4Hs borrowed from the US Army Air Service at Langley Field. One of the first research projects of the laboratory initiated that year was a flight investigation of the lift and drag characteristics of the JN-4H. One of the objectives of the flight tests was to obtain data for correlation with wind-tunnel test results measured at MIT and to aid in the derivation of techniques for extrapolation of model results to full-scale conditions. In a pioneering aeronautical effort in 1920, pressure orifices were installed in the horizontal tail of one of the Jennies and connected to glass manometers for pressure measurements that could be photographed in flight. The NACA also used the aircraft in some of the earliest experiments on maneuverability in 1921. In addition to serving as test subjects, the aircraft were used for measurements of aerodynamic behavior of aircraft components. In this photograph made in 1921, one of the JN- 4Hs is towing a model of an aircraft wing to obtain lift and drag information for comparison to tunnel results. All three Jenny aircraft departed Langley in 1923. Reference: 'Flying the Frontiers: NACA and NASA Experimental Aircraft' by Arthur Pearcy. Naval Institute Press, 1993. ISBN 1-55750-258-7

  7. National 4-H School Enrichment Survey.

    ERIC Educational Resources Information Center

    Diem, Keith G.

    2001-01-01

    A survey of 4-H school enrichment programs (813 responses) found that they reach large numbers of diverse youth and develop credibility with community and schools. Long-term programs such as 4-H clubs have proven effective in helping youth develop life skills, but Extension must carefully consider the purpose and consequences of diverting…

  8. Holding on to 4-H Leaders.

    ERIC Educational Resources Information Center

    Hass, Glen

    1979-01-01

    Data from a survey of 4-H Club leaders in Saskatchewan, Canada, were used to determine the effect of attendance at leadership training events on leaders' decisions to re-enroll or discontinue. It was found that involvement in 4-H activities, supported by leadership training, increased leaders' satisfaction and likelihood of re-enrolling. (MF)

  9. Community Development: A 4-H Intern Report.

    ERIC Educational Resources Information Center

    Scheneman, C. Stephen

    State progress reports on the 4-H/Community Development program, a 1973 nationwide Federally sponsored program facilitating youth in community decision-making processes, indicate that the program appears to be evolving into a viable and integral part of the total 4-H program. Although the report describes unique program features of various States,…

  10. The Big E (Energy). 4-H Member Guide, Unit 3.

    ERIC Educational Resources Information Center

    Caldwell, William; And Others

    This activity and record book is designed for unit 3 (ages 15-19) of the Nebraska 4-H Energy Project. Aims, energy attitudes to be developed, and instructions are provided for each activity. Activities include: (1) determining ways to reduce energy waste with hot water heaters; (2) making personal choices about using appliances; (3) conducting a…

  11. The Big E (Energy). 4-H Member Guide, Unit 2.

    ERIC Educational Resources Information Center

    Caldwell, William; And Others

    This activity and record book is designed for unit 2 (ages 12-14) of the Nebraska 4-H Energy Project. Aims, energy attitudes to be developed, and instructions are provided for each activity. Activities include: (1) a word search of energy-related words (with definitions provided); (2) determining fuel waste; (3) reading electric/gas meters and…

  12. Relationships between 4-H Volunteer Leader Competencies and Skills Youth Learn in 4-H Programs

    ERIC Educational Resources Information Center

    Radhakrishna, Rama; Ewing, John C.

    2011-01-01

    This article examined the relationships between 4-H volunteer leader competencies and skills youth learn in 4-H. Using a descriptive-correlational research, the study reported found significant relationships between leadership competencies and skills youth learn in 4-H. Regression analysis revealed that two variables--skills and…

  13. Livestock Judges Training Provides Hands-On Experience

    ERIC Educational Resources Information Center

    Nash, Scott; Harrison, Steve; Packham, Joel; Sanchez, Dawn; Jensen, Jim; Kaysen, Brett; King, Marc

    2016-01-01

    The judging of a market animal at a fair is the highlight of a youth-owned livestock project. Livestock judges are hired to evaluate youth projects at fairs. They are critical ambassadors for agriculture and influence countless youths and adults. Judges must be knowledgeable about current animal evaluation methods that support youth development.…

  14. 4-H Science Inquiry Video Series

    ERIC Educational Resources Information Center

    Green, Jeremy W.; Black, Lynette; Willis, Patrick

    2013-01-01

    Studies support science inquiry as a positive method and approach for 4-H professionals and volunteers to use for teaching science-based practices to youth. The development of a science inquiry video series has yielded positive results as it relates to youth development education and science. The video series highlights how to conduct science-rich…

  15. Seniors and Youth: Learning and Sharing. An Intergenerational Project Created and Conducted with the Tama County Iowa 4-H Clubs, Mesquaki Indian Settlement School, and the Cedar Falls Public Schools (1983-88).

    ERIC Educational Resources Information Center

    Matters, Lorine

    This document describes the intergenerational project conducted in the Cedar Falls Public School System (Iowa) that involved senior citizens and youths in a learning and sharing process. The county-based extension service supported by faculty at Iowa State University assisted in the recruitment and training of senior citizen volunteers.…

  16. Effectiveness of the 4-H Program as Perceived by Parents of 4-H Participants

    ERIC Educational Resources Information Center

    Radhakrishna, Rama; Foley, Caitlin; Ingram, Patreese; Ewing, John C.

    2013-01-01

    The study reported here examined the effectiveness of 4-H program as perceived by parents of program participants. Descriptive-correlational design was employed, with data collected using a mail survey. Parents perceived 4-H as an effective organization in teaching life skills to youth. Significant relationships were found between parents' skills…

  17. National 4-H Common Measures: Initial Evaluation from California 4-H

    ERIC Educational Resources Information Center

    Lewis, Kendra M.; Horrillo, Shannon J.; Widaman, Keith; Worker, Steven M.; Trzesniewski, Kali

    2015-01-01

    Evaluation is a key component to learning about the effectiveness of a program. This article provides descriptive statistics of the newly developed National 4-H Common Measures (science, healthy living, citizenship, and youth development) based on data from 721 California 4-H youth. The measures were evaluated for their reliability and validity of…

  18. Design and descriptive epidemiology of the Infectious Diseases of East African Livestock (IDEAL) project, a longitudinal calf cohort study in western Kenya

    PubMed Central

    2013-01-01

    Background There is a widely recognised lack of baseline epidemiological data on the dynamics and impacts of infectious cattle diseases in east Africa. The Infectious Diseases of East African Livestock (IDEAL) project is an epidemiological study of cattle health in western Kenya with the aim of providing baseline epidemiological data, investigating the impact of different infections on key responses such as growth, mortality and morbidity, the additive and/or multiplicative effects of co-infections, and the influence of management and genetic factors. A longitudinal cohort study of newborn calves was conducted in western Kenya between 2007-2009. Calves were randomly selected from all those reported in a 2 stage clustered sampling strategy. Calves were recruited between 3 and 7 days old. A team of veterinarians and animal health assistants carried out 5-weekly, clinical and postmortem visits. Blood and tissue samples were collected in association with all visits and screened using a range of laboratory based diagnostic methods for over 100 different pathogens or infectious exposures. Results The study followed the 548 calves over the first 51 weeks of life or until death and when they were reported clinically ill. The cohort experienced a high all cause mortality rate of 16% with at least 13% of these due to infectious diseases. Only 307 (6%) of routine visits were classified as clinical episodes, with a further 216 reported by farmers. 54% of calves reached one year without a reported clinical episode. Mortality was mainly to east coast fever, haemonchosis, and heartwater. Over 50 pathogens were detected in this population with exposure to a further 6 viruses and bacteria. Conclusion The IDEAL study has demonstrated that it is possible to mount population based longitudinal animal studies. The results quantify for the first time in an animal population the high diversity of pathogens a population may have to deal with and the levels of co-infections with key

  19. VIBRATIONALLY EXCITED C{sub 4}H

    SciTech Connect

    Cooksy, Andrew L.; Gottlieb, C. A.; Thaddeus, P.; Patel, Nimesh A.; Young, Ken H.; McCarthy, M. C.; Killian, T. C.

    2015-02-01

    Rotational spectra in four new excited vibrational levels of the linear carbon chain radical C{sub 4}H were observed in the millimeter band between 69 and 364 GHz in a low pressure glow discharge, and two of these were observed in a supersonic molecular beam between 19 and 38 GHz. All have rotational constants within 0.4% of the X{sup 2}Σ{sup +} ground vibrational state of C{sub 4}H and were assigned to new bending vibrational levels, two each with {sup 2}Σ and {sup 2}Π vibrational symmetry. The new levels are tentatively assigned to the 1ν{sub 6} and 1ν{sub 5} bending vibrational modes (both with {sup 2}Π symmetry), and the 1ν{sub 6}+1ν{sub 7} and 1ν{sub 5}+1ν{sub 6} combination levels ({sup 2}Σ symmetry) on the basis of the derived spectroscopic constants, relative intensities in our discharge source, and published laser spectroscopic and quantum calculations. Prior spectroscopic constants in the 1ν{sub 7} and 2ν{sub 7} levels were refined. Also presented are interferometric maps of the ground state and the 1ν{sub 7} level obtained with the Submillimeter Array (SMA) near 257 GHz which show that C{sub 4}H is present near the central star in IRC+10216. We found no evidence with the SMA for the new vibrationally excited levels of C{sub 4}H at a peak flux density averaged over a 3{sup ′′} synthesized beam of ⩾0.15 Jy/beam in the 294–296 and 304–306 GHz range, but it is anticipated that rotational lines in the new levels might be observed in IRC+10216 when ALMA attains its full design capability.

  20. What have we learned from the current state of genomics in livestock?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Livestock genomics is leveraging the genomic information, methods, and technology spawned from the human genome sequencing project. This conference has addressed the following critical areas of research in livestock: genome evolution, genomic variation, epigenomics, food security, and sequencing a...

  1. Climate change mitigation through livestock system transitions

    PubMed Central

    Havlík, Petr; Valin, Hugo; Herrero, Mario; Obersteiner, Michael; Schmid, Erwin; Rufino, Mariana C.; Mosnier, Aline; Thornton, Philip K.; Böttcher, Hannes; Conant, Richard T.; Frank, Stefan; Fritz, Steffen; Fuss, Sabine; Kraxner, Florian; Notenbaert, An

    2014-01-01

    Livestock are responsible for 12% of anthropogenic greenhouse gas emissions. Sustainable intensification of livestock production systems might become a key climate mitigation technology. However, livestock production systems vary substantially, making the implementation of climate mitigation policies a formidable challenge. Here, we provide results from an economic model using a detailed and high-resolution representation of livestock production systems. We project that by 2030 autonomous transitions toward more efficient systems would decrease emissions by 736 million metric tons of carbon dioxide equivalent per year (MtCO2e⋅y−1), mainly through avoided emissions from the conversion of 162 Mha of natural land. A moderate mitigation policy targeting emissions from both the agricultural and land-use change sectors with a carbon price of US$10 per tCO2e could lead to an abatement of 3,223 MtCO2e⋅y−1. Livestock system transitions would contribute 21% of the total abatement, intra- and interregional relocation of livestock production another 40%, and all other mechanisms would add 39%. A comparable abatement of 3,068 MtCO2e⋅y−1 could be achieved also with a policy targeting only emissions from land-use change. Stringent climate policies might lead to reductions in food availability of up to 200 kcal per capita per day globally. We find that mitigation policies targeting emissions from land-use change are 5 to 10 times more efficient—measured in “total abatement calorie cost”—than policies targeting emissions from livestock only. Thus, fostering transitions toward more productive livestock production systems in combination with climate policies targeting the land-use change appears to be the most efficient lever to deliver desirable climate and food availability outcomes. PMID:24567375

  2. Matching Livestock Production Systems and Environment

    NASA Astrophysics Data System (ADS)

    Becchetti, T.; Stackhouse, J.; Snell, L.; Lile, D.; George, H.; Harper, J. M.; Larson, S.; Mashiri, F.; Doran, M.; Barry, S.

    2015-12-01

    Livestock production systems vary greatly over the world. Producers try to match the resources they have with the demands of production, this can vary by species, class of animal, number of animals, and production goals, etc. Using California's diversity in production systems as an example, we explored how livestock producers best utilize the forage and feed found in different ecosystems and available in different parts of the state. Livestock grazing, the predominant land use in California and in much of the world, makes efficient use of the natural vegetation produced without additional water (irrigation), minimal inputs such as fertilizer while often supporting a variety of conservation objectives including vegetation management, fire fuels management, and habitat and open space conservation. The numerous by-products produced by other sectors of California's agriculture as well as food industries, such as brewer's grain, cottonseeds, and almond hulls are utilized as a feed source for livestock. These by-products are not only an important feed source especially in drought years but are diverted from our waste stream when utilized by livestock. The concept of matching available resources to livestock needs throughout the world is often overlooked and production systems are often over simplified in projects conducting a life cycle analysis or developing carbon foot prints for livestock production systems. This paper provides details on the various production systems found in California, the ecosystem they have adapted to, and how the producers use science and ecological knowledge to match the biological requirements of the livestock and conservation objectives to feed and forage resources.

  3. Climate change mitigation through livestock system transitions.

    PubMed

    Havlík, Petr; Valin, Hugo; Herrero, Mario; Obersteiner, Michael; Schmid, Erwin; Rufino, Mariana C; Mosnier, Aline; Thornton, Philip K; Böttcher, Hannes; Conant, Richard T; Frank, Stefan; Fritz, Steffen; Fuss, Sabine; Kraxner, Florian; Notenbaert, An

    2014-03-11

    Livestock are responsible for 12% of anthropogenic greenhouse gas emissions. Sustainable intensification of livestock production systems might become a key climate mitigation technology. However, livestock production systems vary substantially, making the implementation of climate mitigation policies a formidable challenge. Here, we provide results from an economic model using a detailed and high-resolution representation of livestock production systems. We project that by 2030 autonomous transitions toward more efficient systems would decrease emissions by 736 million metric tons of carbon dioxide equivalent per year (MtCO2e⋅y(-1)), mainly through avoided emissions from the conversion of 162 Mha of natural land. A moderate mitigation policy targeting emissions from both the agricultural and land-use change sectors with a carbon price of US$10 per tCO2e could lead to an abatement of 3,223 MtCO2e⋅y(-1). Livestock system transitions would contribute 21% of the total abatement, intra- and interregional relocation of livestock production another 40%, and all other mechanisms would add 39%. A comparable abatement of 3,068 MtCO2e⋅y(-1) could be achieved also with a policy targeting only emissions from land-use change. Stringent climate policies might lead to reductions in food availability of up to 200 kcal per capita per day globally. We find that mitigation policies targeting emissions from land-use change are 5 to 10 times more efficient--measured in "total abatement calorie cost"--than policies targeting emissions from livestock only. Thus, fostering transitions toward more productive livestock production systems in combination with climate policies targeting the land-use change appears to be the most efficient lever to deliver desirable climate and food availability outcomes.

  4. Learnings and Recommendations to Advance 4-H Science Readiness

    ERIC Educational Resources Information Center

    Schmitt-McQuitty, Lynn; Carlos, Ramona; Smith, Martin H.

    2014-01-01

    The case study investigation reported here assessed California 4-H professionals' understanding of the essential components of effective 4-H Science programming as established by the National 4-H Science Mission Mandate. Using the 4-H Science Checklist as the basis for defining 4-H Science Readiness, academic and program staff were surveyed and…

  5. 4-H and Tech Ed Partnership Gets Students Geeked about STEM

    ERIC Educational Resources Information Center

    Ivey, Debra; Quam, Greg

    2009-01-01

    This article discusses the 4-H Gateway Academies specifically designed to enhance science, technology, engineering, and math (STEM) skills and knowledge in middle school youth. The innovative summer day camps partnered Project Lead the Way--trained teachers with county 4-H staff from University of Wisconsin-Extension (UW-Extension) Cooperative…

  6. Fitting the Framework: The STEM Institute and the 4-H Essential Elements

    ERIC Educational Resources Information Center

    Sallee, Jeff; Peek, Gina G.

    2014-01-01

    Extension and 4-H youth development programs are addressing a shortage of scientists, engineers, and other related professionals by promoting science, technology, engineering, and math (STEM). This case study illustrates how the Oklahoma 4-H Youth Development program trained youth-adult teams to design and implement STEM projects. The STEM…

  7. Wiggles and Wags: Dog 1--Fun Activities for You and Your Dog. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08166

    ERIC Educational Resources Information Center

    National 4-H Council, 2005

    2005-01-01

    These guides are activity guides. Several fact-filled books about dogs are listed as resources on this guide. The activities are active, hands-on, and engaging and are guided by the 4-H motto: Learning by Doing. As youth explore a dog project topic of interest to them, they also practice essential life skills. Although a few dog project youth will…

  8. Revised spatially distributed global livestock emissions

    NASA Astrophysics Data System (ADS)

    Asrar, G.; Wolf, J.; West, T. O.

    2015-12-01

    Livestock play an important role in agricultural carbon cycling through consumption of biomass and emissions of methane. Quantification and spatial distribution of methane and carbon dioxide produced by livestock is needed to develop bottom-up estimates for carbon monitoring. These estimates serve as stand-alone international emissions estimates, as input to global emissions modeling, and as comparisons or constraints to flux estimates from atmospheric inversion models. Recent results for the US suggest that the 2006 IPCC default coefficients may underestimate livestock methane emissions. In this project, revised coefficients were calculated for cattle and swine in all global regions, based on reported changes in body mass, quality and quantity of feed, milk production, and management of living animals and manure for these regions. New estimates of livestock methane and carbon dioxide emissions were calculated using the revised coefficients and global livestock population data. Spatial distribution of population data and associated fluxes was conducted using the MODIS Land Cover Type 5, version 5.1 (i.e. MCD12Q1 data product), and a previously published downscaling algorithm for reconciling inventory and satellite-based land cover data at 0.05 degree resolution. Preliminary results for 2013 indicate greater emissions than those calculated using the IPCC 2006 coefficients. Global total enteric fermentation methane increased by 6%, while manure management methane increased by 38%, with variation among species and regions resulting in improved spatial distributions of livestock emissions. These new estimates of total livestock methane are comparable to other recently reported studies for the entire US and the State of California. These new regional/global estimates will improve the ability to reconcile top-down and bottom-up estimates of methane production as well as provide updated global estimates for use in development and evaluation of Earth system models.

  9. Agriculture. Beef Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for beef livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

  10. Livestock. Student Learning Guides.

    ERIC Educational Resources Information Center

    Ridge Vocational-Technical Center, Winter Haven, FL.

    These 25 learning guides are self-instructional packets for 25 tasks identified as essential for performance on an entry-level job in livestock production. Each guide is based on a terminal performance objective (task) and 1-4 enabling objectives. For each enabling objective, some or all of these materials may be presented: learning steps (outline…

  11. Agriculture. Dairy Livestock.

    ERIC Educational Resources Information Center

    Michigan State Univ., East Lansing. Coll. of Agriculture and Natural Resources Education Inst.

    This task-based curriculum guide for agricultural production, specifically for dairy livestock, is intended to help the teacher develop a classroom management system where students learn by doing. Introductory materials include a Dictionary of Occupational Titles job code and title sheet, a task sheet for developing leadership skills, and a task…

  12. Brucellosis vaccines for livestock.

    PubMed

    Goodwin, Zakia I; Pascual, David W

    2016-11-15

    Brucellosis is a livestock disease responsible for fetal loss due to abortions. Worldwide, this disease has profound economic and social impact by reducing the ability of livestock producers to provide an adequate supply of disease-free meat and dairy products. In addition to its presence in domesticated animals, brucellosis is harbored in a number of wildlife species creating new disease reservoirs, which adds to the difficulty of eradicating this disease. Broad and consistent use of the available vaccines would contribute in reducing the incidence of brucellosis. Unfortunately, this practice is not common. In addition, the current brucellosis vaccines cannot provide sterilizing immunity, and in certain circumstances, vaccinated livestock are not protected against co-mingling Brucella-infected wildlife. Given that these vaccines are inadequate for conferring complete protection for some vaccinated livestock, alternatives are being sought, and these include genetic modifications of current vaccines or their reformulations. Alternatively, many groups have sought to develop new vaccines. Subunit vaccines, delivered as a combination of soluble vaccine plus adjuvant or the heterologous expression of Brucella epitopes by different vaccine vectors are currently being tested. New live attenuated Brucella vaccines are also being developed and tested in their natural hosts. Yet, what is rarely considered is the route of vaccination which could improve vaccine efficacy. Since Brucella infections are mostly transmitted mucosally, mucosal delivery of a vaccine has the potential of eliciting a more robust protective immune response for improved efficacy. Hence, this review will examine these questions and provide the status of new vaccines for livestock brucellosis.

  13. Diversity Inclusion in 4-H Youth Programs: Examining the Perceptions among West Virginia 4-H Youth Professionals

    ERIC Educational Resources Information Center

    LaVergne, Douglas D.

    2013-01-01

    The study reported here sought to examine the perceptions of 4-H youth professionals towards diversity inclusion in 4-H youth programs. A majority of professionals positively reported that there are benefits for youth of color and youth with disabilities in 4-H youth programs. Respondents indicated that the lack of information about 4-H youth…

  14. Livestock models in translational medicine.

    PubMed

    Roth, James A; Tuggle, Christopher K

    2015-01-01

    This issue of the ILAR Journal focuses on livestock models in translational medicine. Livestock models of selected human diseases present important advantages as compared with rodent models for translating fundamental breakthroughs in biology to useful preventatives and therapeutics for humans. Livestock reflect the complexity of applying medical advances in an outbred species. In many cases, the pathogenesis of infectious, metabolic, genetic, and neoplastic diseases in livestock species more closely resembles that in humans than does the pathogenesis of rodent models. Livestock models also provide the advantage of similar organ size and function and the ability to serially sample an animal throughout the study period. Research using livestock models for human disease often benefits not only human health but animal health and food production as well. This issue of the ILAR Journal presents information on translational research using livestock models in two broad areas: microbiology and infectious disease (transmissible spongiform encephalopathies, mycobacterial infections, influenza A virus infection, vaccine development and testing, the human microbiota) and metabolic, neoplastic, and genetic disorders (stem cell therapy, male germ line cell biology, pulmonary adenocarcinoma, muscular dystrophy, wound healing). In addition, there is a manuscript devoted to Institutional Animal Care and Use Committees' responsibilities for reviewing research using livestock models. Conducting translational research using livestock models requires special facilities and researchers with expertise in livestock. There are many institutions in the world with experienced researchers and facilities designed for livestock research; primarily associated with colleges of agriculture and veterinary medicine or government laboratories.

  15. Promoting the Essential Elements of 4-H Youth Development through an Experiential Learning Model

    ERIC Educational Resources Information Center

    Meyer, Shelley; Jones, Kenneth R.

    2015-01-01

    The purpose of the project reported here was to apply Experiential Learning Theory to a context involving middle and high school aged youth while assessing the four concepts (belonging, mastery, independence, and generosity) in relation to the 4-H youth development essential elements. The conclusions of the project's evaluation suggest…

  16. A Partnership Model for Training Episodic Environmental Stewardship 4-H Volunteers

    ERIC Educational Resources Information Center

    Young, Jane Chin; Alexander, Janice; Smith, Martin H.

    2013-01-01

    The Marin Environmental Stewardship pilot project demonstrates the potential for a partnership model that brings together external and internal collaborators to recruit and train episodic 4-H volunteers to meet environmental education needs within a community. The clientele served by the volunteers trained through the project was at-risk, urban…

  17. The Big E (Energy). 4-H Leader's Guide [for Unit 1].

    ERIC Educational Resources Information Center

    Caldwell, William; And Others

    This guide is designed for leaders of the Nebraska 4-H Energy Project. The goals of the project are to: (1) help young people understand energy problems related to life styles; (2) use energy resources carefully; (3) guide members in choosing their own energy alternatives; and (4) enjoy together the challenges and creativity of finding energy…

  18. The Big E (Energy). 4-H Leader's Guide for Units 2 & 3.

    ERIC Educational Resources Information Center

    Caldwell, William; And Others

    This leader's guide is designed for units 2 and 3 of the Nebraska 4-H Energy Project. The goals of the project are to: (1) help young people understand energy problems related to life styles; (2) use energy resources carefully; (3) guide members in choosing their own energy alternatives; and (4) to enjoy together the challenges and creativity of…

  19. Using Digital Classrooms to Conduct 4-H Club Meetings

    ERIC Educational Resources Information Center

    West, Patricia; Fuhrman, Nicholas E.; Morgan, A. Christian; Duncan, Dennis W.

    2012-01-01

    Using computer technology and digital classrooms to conduct 4-H Club meetings is an efficient way to continue delivering quality 4-H programming during times of limited resources and staff. Nineteen Junior and Senior 4-H'ers participated in seven digital classroom workshops using the Wimba Classroom application. These digital classroom sessions…

  20. Hamsters?! What Does 4-H Stand for, Anyway?

    ERIC Educational Resources Information Center

    Grundeen, Brenda

    This paper briefly traces the history of 4-H youth development programs, explains what youth development is, and shows how the experiential learning model is used in 4-H. Begun over 75 years ago as a means of extending the learning of the land-grant university to rural youth, 4-H is part of the Cooperative Extension Service. The curriculum…

  1. The 4-H Club Meeting: An Essential Youth Development Strategy

    ERIC Educational Resources Information Center

    Cassels, Alicia; Post, Liz; Nestor, Patrick I.

    2015-01-01

    The club meeting has served as a key delivery method for 4-H programming across the United States throughout its history. A survey of WV 4-H community club members reinforces the body of evidence that the 4-H club meeting is an effective vehicle for delivering positive youth learning opportunities within the umbrella of the Essential Elements of…

  2. Factors Affecting Teen Involvement in Pennsylvania 4-H Programming

    ERIC Educational Resources Information Center

    Gill, Bart E.; Ewing, John C.; Bruce, Jacklyn A.

    2010-01-01

    The study reported here determined the factors that affect teen involvement in 4-H programming. The design of the study was descriptive and correlational in nature. Using a purposive sampling procedure, a survey questionnaire was distributed to all (N=214) 4-H members attending the 4-H State Leadership Conference. The major findings of the study…

  3. Streamlined Livestock Trailer

    NASA Astrophysics Data System (ADS)

    1980-01-01

    Bull Nose livestock trailer, manufactured by American Trailer, Inc. is one of a line of highway transport vehicles manufactured by American Trailers, Inc. The slant side front end is a streamlining feature based on a NASA Research Program which investigated the aerodynamic characteristics of trailer/tractor combinations and suggested ways of reducing air resistance. Application of NASA's aerodynamic research technology to the bull nose design resulted in a 10 percent reduction in air drag, which translates into annual fuel savings of several hundred dollars.

  4. Detecting livestock production zones.

    PubMed

    Grisi-Filho, J H H; Amaku, M; Ferreira, F; Dias, R A; Neto, J S Ferreira; Negreiros, R L; Ossada, R

    2013-07-01

    Communities are sets of nodes that are related in an important way, most likely sharing common properties and/or playing similar roles within a network. Unraveling a network structure, and hence the trade preferences and pathways, could be useful to a researcher or a decision maker. We implemented a community detection algorithm to find livestock communities, which is consistent with the definition of a livestock production zone, assuming that a community is a group of farm premises in which an animal is more likely to stay during its lifetime than expected by chance. We applied this algorithm to the network of animal movements within the state of Mato Grosso for 2007. This database holds information concerning 87,899 premises and 521,431 movements throughout the year, totaling 15,844,779 animals moved. The community detection algorithm achieved a network partition that shows a clear geographical and commercial pattern, two crucial features for preventive veterinary medicine applications; this algorithm provides also a meaningful interpretation to trade networks where links emerge based on trader node choices.

  5. Twenty-first century learning after school: the case of 4-H.

    PubMed

    Kress, Cathann

    2006-01-01

    Founded in the early 1900s, the 4-H Youth Development program can serve as a model for out-of-school programs of the twenty-first century. The 4-H pledge, repeated by its members--over 7 million, ranging in age from five to twenty--articulates its core values: "I pledge: My head to clearer thinking, My heart to greater loyalty, My hands to larger service, and My health to better living for my club, my community, my country, and my world." The 4-H Development movement was created to provide opportunities for rural children, to help them become constructive adults. Through an emphasis on "learning by doing," 4-H teaches children the habits of lifelong learning. Historically, 4-H has tapped into university-level advancements, extending such knowledge to youth and thereby giving them early access to scientific discoveries and technological progress. Members apply this learning in their communities through hands-on projects crossing a wide-range of pertinent topics. Research shows that 4-H members are more successful in school than other children and develop a wide range of skills essential in the twenty-first century. Thus, the author makes the case that the foundation of 4-H is exceptionally relevant in today's complex world, perhaps even more so than a century ago. 4-H is a leader in youth development, making it a natural model for twenty-first century after-school programs. Expanding on the 4-H pledge, the author outlines the principles a successful youth development program would have: an emphasis on leadership skills, a feeling of connection and belonging, a forum for exploring career opportunities, and a component of meaningful community service.

  6. Unexpected Stability of Al4H6: a Borane Analog?

    NASA Astrophysics Data System (ADS)

    Xi, Li; Grubisic, Andrej; Stokes, Sarah; Gantefor, Gerd; Bowen, Kit; Boggavarapu, Kiran; Willis, Mary; Jena, Puru; Burgert, Ralph; Schnockel, Hans; Cordes, James

    2007-03-01

    While boron has many hydrides, aluminum has been thought to exhibit relatively few. A combined anion photoelectron and density functional theory computational study of the Al4H6^- anion, and its corresponding neutral, Al4H6, showed that Al4H6 can be understood in terms of the Wade-Mingos rules for electron counting, suggesting that it may be a borane analog. The data support an Al4H6 structure with a distorted tetrahedral aluminum atom framework, four terminal Al-H bonds, and two sets of counter-positioned Al-H-Al bridging bonds. The large HOMO-LUMO gap found for Al4H6 together with its exceptionally high heat of combustion further suggests that Al4H6 may be an important energetic material, if it can be prepared in bulk. This report announces the opening of a new chapter in aluminum-hydrogen chemistry.

  7. The Effectiveness of Videotape Programs as a Communication Tool in the Small-Scale Livestock for Rural Farming Women Project, Honduras.

    ERIC Educational Resources Information Center

    Johnson-Dean, Lynn

    This study examines economic development in Third World countries and the use of portable video systems in development projects. The study, conducted in 1985, attempts to measure the level of effectiveness of videotape programs as a communication tool for training rural subsistence women in Honduras in technical aspects of pig-keeping. Classical…

  8. The Oneida County 4-H Conservation Field Days Conflict.

    ERIC Educational Resources Information Center

    Brown, Stephen C.; Vonhof, Sarah; Kelley, Alicia

    2003-01-01

    Examines the various perspectives held by the three major organizations involved (an environmental citizens group, a local sportsmen's club, and the cooperative extension service) regarding a conflict over a 4-H program involving hunting and wildlife management. Discusses why the 4-H program's attempt to build consensus among the organizations was…

  9. Camping with a Purpose...A 4-H Handbook.

    ERIC Educational Resources Information Center

    Heller, John H.; And Others

    The 4-H handbook focuses on factors to consider and things to be done when developing a camping program. Since the emphasis, structure, and administration of 4-H camping varies, the booklet is flexible enough to be adapted to different state, district, and county situations. Major topics are camping's importance to extension education,…

  10. Council of Presidents: A Multifaceted Idea for 4-H

    ERIC Educational Resources Information Center

    Torretta, Alayne

    2015-01-01

    Communication between 4-H professionals and the youth they work with is an important part of a successful 4-H program. By creating a Council of Presidents comprised of officers of all the clubs in your county, you can increase communication while assuring your program addresses all four essential elements. The Council is also as a vehicle for…

  11. Community Pride: An Oregon 4-H Activity Relating to Beautification and Conservation.

    ERIC Educational Resources Information Center

    Oregon State Univ., Corvallis. Cooperative Extension Service.

    The Community Pride program is a 4-H activity in conservation and beautification. Instructions for selecting and carrying out a Community Pride activity are presented: planning, organizing, and doing the project. Suggestions for possible activities are offered, and instructions for reporting the activity to the county extension office are given.…

  12. 4-H Shooting Sports Hits the Mark with Youth-at-Risk.

    ERIC Educational Resources Information Center

    Sabo, Kenneth E.; Hamilton, Wendy V.

    1997-01-01

    A 4-H program in a public housing project in New Mexico involved at-risk youth in activities such as archery and other shooting sports. These activities were found to promote motivation, cognitive development, self-esteem, and responsibility. (SK)

  13. Stabilization of 4H hexagonal phase in gold nanoribbons

    PubMed Central

    Fan, Zhanxi; Bosman, Michel; Huang, Xiao; Huang, Ding; Yu, Yi; Ong, Khuong P.; Akimov, Yuriy A.; Wu, Lin; Li, Bing; Wu, Jumiati; Huang, Ying; Liu, Qing; Eng Png, Ching; Lip Gan, Chee; Yang, Peidong; Zhang, Hua

    2015-01-01

    Gold, silver, platinum and palladium typically crystallize with the face-centred cubic structure. Here we report the high-yield solution synthesis of gold nanoribbons in the 4H hexagonal polytype, a previously unreported metastable phase of gold. These gold nanoribbons undergo a phase transition from the original 4H hexagonal to face-centred cubic structure on ligand exchange under ambient conditions. Using monochromated electron energy-loss spectroscopy, the strong infrared plasmon absorption of single 4H gold nanoribbons is observed. Furthermore, the 4H hexagonal phases of silver, palladium and platinum can be readily stabilized through direct epitaxial growth of these metals on the 4H gold nanoribbon surface. Our findings may open up new strategies for the crystal phase-controlled synthesis of advanced noble metal nanomaterials. PMID:26216712

  14. Adult volunteerism in Pennsylvania 4-H natural resources programs for youth

    NASA Astrophysics Data System (ADS)

    Smith, Sanford Sherrick

    2001-07-01

    Pennsylvania's 4-H Youth Development Program relies on adult volunteers to reach youth with educational information and opportunities. Finding adults willing to do this volunteer work is challenging. This study looks at the current status of adult volunteerism with natural resources 4-H projects, and seeks to understand potential volunteers. The literature has much to offer in regards to general volunteer trends, management, motivations, and task preferences; however, few studies focus on volunteers in natural resources or environmental education. A telephone survey conducted with county 4-H agents revealed that only 3.2% of Pennsylvania's 4-H volunteers work with natural resources projects in 56 out of 67 counties, and that very few volunteers have any formal background in natural resources. Semi-structured interviews with 41 adult volunteers currently working with natural resources projects explored volunteer demographics, history, program design preferences, and ideas for seeking more volunteers. Findings from the telephone survey and the semi-structured interviews were used to generate a mail survey with large, random samples from three population groups: (1) 4-H Volunteers, (2) 4-H Parents, and (3) Natural Resources Professionals. Confidence with youth and subject matter, and adult willingness to volunteer was explored for each of the groups in relation to background, demographic characteristics, motivational needs, past and present volunteer activity, personal interests, and program design importance. Natural resources subject matter confidence was shown to be the most significant variable determining willingness to volunteer for all three groups. The variables that contributed to subject matter and youth confidence varied for each population. Key variables effecting willingness to volunteer included outdoor activity level, personal interest in natural resources, the need to fulfill feelings of social responsibility, and confidence with youth. Program design

  15. Texas 4-H Agents' Perceptions of Selected Competencies in the 4-H Professional Research, Knowledge, and Competencies Model

    ERIC Educational Resources Information Center

    Harder, Amy; Wingenbach, Gary J.

    2008-01-01

    There are many competencies necessary for success as a 4-H agent. The 4-H Professional Research, Knowledge, and Competencies (PRKC) Model organizes competencies into six domains: (a) Youth Development, (b) Youth Program Development, (c) Volunteerism, (d) Partnerships, (e) Organizational Systems, and (f) Equity, Access and Opportunity (National 4-H…

  16. Determination of the contribution of livestock water ingestion to dose from the cow-milk pathway. Hanford Environmental Dose Reconstruction Project: Dose code recovery activities, Calculation 002

    SciTech Connect

    Ikenberry, T.A.

    1992-12-01

    As part of the Hanford Environmental Dose Reconstruction (HEDR) Project, a series of calculations has been undertaken to evaluate the absolute and relative contribution of different exposure pathways to thyroid doses that may have been received by individuals living in the vicinity of the Hanford Site. These evaluations include some pathways that were included in the Phase I air-pathway dose evaluations (HEDR staff 1991, page xx), as well as other potential exposure pathways being evaluated for possible inclusion in the future HEDR modeling efforts. This calculation (002) examined the possible doses that may have been received by individuals who drank milk from cows that drank from sources of water (stock tanks and farm ponds) exposed to iodine-131 in the atmosphere during 1945.

  17. 25 CFR 700.725 - Livestock trespass.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Grazing § 700.725 Livestock trespass. The following acts are prohibited: (a) The grazing of livestock upon, or driving of livestock across, any of the New Lands without a current approved grazing or crossing permit. (b) The grazing of livestock upon an area specifically rested from the grazing of...

  18. 25 CFR 168.14 - Livestock trespass.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Livestock trespass. 168.14 Section 168.14 Indians BUREAU... PARTITIONED LANDS AREA § 168.14 Livestock trespass. The owner of any livestock grazing in trespass on the Hopi... Hopi Partitioned Lands of any livestock without an approved grazing or crossing permit; (b)...

  19. 36 CFR 261.7 - Livestock.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Livestock. 261.7 Section 261... Prohibitions § 261.7 Livestock. The following are prohibited: (a) Placing or allowing unauthorized livestock to... unauthorized livestock from the National Forest System or other lands under Forest Service control...

  20. Sodium diffusion in 4H-SiC

    SciTech Connect

    Linnarsson, M. K. Hallén, A.

    2014-09-01

    Sodium diffusion has been studied in p-type 4H-SiC. Heat treatments have been performed from 1200 °C to 1800 °C for 1 min to 4 h. Secondary ion mass spectrometry has been used to measure the sodium distribution. We show that sodium has a considerable mobility at 1200 °C in p-type 4H-SiC. On the other hand for sodium atoms trapped at suitable sites the mobility is limited up to 1800 °C. Trap limited diffusion kinetics is suggested and an effective diffusivity has been extracted with an activation energy of 4 eV for sodium diffusion in p-type 4H-SiC.

  1. A Science, Engineering and Technology (SET) Approach Improves Science Process Skills in 4-H Animal Science Participants

    ERIC Educational Resources Information Center

    Clarke, Katie C.

    2010-01-01

    A new Science, Engineering and Technology (SET) approach was designed for youth who participated in the Minnesota State Fair Livestock interview process. The project and evaluation were designed to determine if the new SET approach increased content knowledge and science process skills in participants. Results revealed that youth participants not…

  2. Draft Genome Sequences of Campylobacter jejuni Strains That Cause Abortion in Livestock

    PubMed Central

    Weis, Allison M.; Clothier, Kristin A.; Huang, Bihua C.; Kong, Nguyet

    2016-01-01

    Campylobacter jejuni is an intestinal bacterium that can cause abortion in livestock. This publication announces the public release of 15 Campylobacter jejuni genome sequences from isolates linked to abortion in livestock. These isolates are part of the 100K Pathogen Genome Project and are from clinical cases at the University of California (UC) Davis. PMID:27908990

  3. Foodborne illness associated with Cryptosporidium and Giardia from livestock.

    PubMed

    Budu-Amoako, Ebo; Greenwood, Spencer J; Dixon, Brent R; Barkema, Herman W; McClure, J T

    2011-11-01

    Waterborne outbreaks caused by Cryptosporidium and Giardia are well documented, while the public health implications for foodborne illness from these parasites have not been adequately considered. Cryptosporidium and Giardia are common in domestic livestock, where young animals can have a high prevalence of infection, shedding large numbers of oocysts and cysts. Molecular epidemiological studies have advanced our knowledge on the distribution of Cryptosporidium and Giardia species and genotypes in specific livestock. This has enabled better source tracking of contaminated foods. Livestock generate large volumes of fecal waste, which can contaminate the environment with (oo)cysts. Evidence suggests that livestock, particularly cattle, play a significant role in food contamination, leading to outbreaks of cryptosporidiosis. However, foodborne giardiasis seems to originate primarily from anthroponotic sources. Foodborne cryptosporidiosis and giardiasis are underreported because of the limited knowledge of the zoonotic potential and public health implications. Methods more sensitive and cheaper are needed to detect the often-low numbers of (oo)cysts in contaminated food and water. As the environmental burden of Cryptosporidium oocysts and Giardia cysts from livestock waste increases with the projected increase in animal agriculture, public health is further compromised. Contamination of food by livestock feces containing Cryptosporidium oocysts and Giardia cysts could occur via routes that span the entire food production continuum. Intervention strategies aimed at preventing food contamination with Cryptosporidium and Giardia will require an integrated approach based on knowledge of the potential points of entry for these parasites into the food chain. This review examines the potential for foodborne illness from Cryptosporidium and Giardia from livestock sources and discusses possible mechanisms for prevention and control.

  4. Wetlands Are Wonderlands. Leader/Teacher Guide and Member/Youth Guide. 4-H Marine Education Series-1.

    ERIC Educational Resources Information Center

    Meenen, Kimberly, Ed.; Goettel, Robin G., Ed.

    This guide, for a 4-H wetlands project, is designed for sixth to eighth grade youth and their leaders interested in learning and doing aquatic science activities that can help the environment. The project provides basic wetland information with one or more activities for each of six sections: (1) What is a wetland?; (2) value of wetlands; (3)…

  5. "Ohio 4-H CARTEENS": Peer Intervention Safety Program.

    ERIC Educational Resources Information Center

    Cropper, Rebecca J.

    1999-01-01

    Ohio 4-H's CARTEENS seeks to reduce juvenile traffic violations in a program designed and presented by teen peer educators with guidance and technical assistance from the state highway patrol. Teens examined court data to determine content, which includes defensive driving, rural road safety, and dealing with peer pressure. (SK)

  6. Minnesota 4-H Youth Program Quality Improvement Model

    ERIC Educational Resources Information Center

    Herman, Margo; Grant, Samantha

    2015-01-01

    The University of Minnesota Extension Center for Youth Development made an organizational decision in 2011 to invest in a system-wide approach to implement youth program quality into the 4-H program using the Youth Program Quality Assessment (YPQA) tool. This article describes the four key components to the Minnesota Youth Program Quality…

  7. Keys To The Kansas Environment. 4-H School Enrichment Program.

    ERIC Educational Resources Information Center

    Kansas State Univ., Manhattan. Extension Service.

    The 4-H Club packet for preschool and elementary school children contains nine "keys", or short learning exercises, designed to enrich science and environmental education both in and out of the classroom. Each "key" includes the purpose of the activity, the intended audience, the best time of the year for the activity,…

  8. Effectiveness of the Indiana 4-H Tractor Program: Alumni Perceptions.

    ERIC Educational Resources Information Center

    Carrabba, James J., Jr.; Talbert, B. Allen; Field, William E.; Tormoehlen, Roger

    2001-01-01

    Responses from Indiana 4-H tractor driving contestants 1982-197 (n=139) showed that 74% were employed on farms; most felt the contests effectively taught tractor safety and made them generally aware of safety. However, many still engaged in risky behaviors such as not wearing seatbelts in tractors with rollover protective structures or allowing…

  9. Implementing and Assessing 4-H Educational Activity Kits for Children

    ERIC Educational Resources Information Center

    Scheer, Scott D.; Yeske, Janine; Zimmer, Bruce

    2011-01-01

    Educational activity kits were developed and implemented through a statewide effort for 4-H Youth Development Extension programs serving 5-8 year-old children. The purpose of the kits was to promote life skills in children and assess the learning environment. Data was collected based on the observations of 577 children across 22 counties. Findings…

  10. South Carolina's Model for Initiating Hispanic 4-H Clubs

    ERIC Educational Resources Information Center

    Lippert, Robert; Rembert, Kellye

    2012-01-01

    Over the past 5 years, through the initiative of several county Extension agents, South Carolina 4-H has established a successful model for bringing Hispanic youth into our program. We have found the most effective method is to initiate contact and establish partnerships with the principals and ESOL instructors in the local schools. Through this…

  11. CONSERVING OUR NATURAL RESOURCES, A 4-H LEADER'S GUIDE.

    ERIC Educational Resources Information Center

    AMICK, W. ROBERT; AND OTHERS

    AN EFFECTIVE 4-H CONSERVATION PROGRAM IS DEVELOPED AROUND THE FOLLOWING BASIC CONCEPTS--(1) MAN IS A PART OF THE NATURAL WORLD, IN WHICH THERE ARE MANY VALUABLE MATERIALS, (2) MAN HAS LEARNED TO USE MANY OF THOSE MATERIALS FOR HUMAN SUSTENANCE AND BETTERMENT, AND (3) MAN'S ECONOMIC, SOCIAL, AND GENERAL WELFARE IS LARGELY DEPENDENT UPON THE MANNER…

  12. A Phenomenological Look at 4-H Volunteer Motives for Service

    ERIC Educational Resources Information Center

    Schrock, Jessalyn; Kelsey, Kathleen D.

    2013-01-01

    Volunteers play a vital role in 4-H programs. Without their service, many programs would not be possible. Understanding volunteer motives provides Extension educators with tools for finding high-quality volunteers. The research reported here used McClelland's (1985) framework for motivation (affiliation, achievement, and power) and…

  13. Fashion Revue. 4-H Textile Science Activity Guide.

    ERIC Educational Resources Information Center

    Scholl, Jan

    This publication was developed to help students participating in Fashion Review, a 4-H event in which students model a clothing outfit and accessories and are judged on their modeling ability, their presentation, and how well the clothing and accessory choices complement the students' skin tones, hair color, figure or physique, personality, and…

  14. Livestock waste: a renewable resource

    SciTech Connect

    Not Available

    1981-01-01

    The 118 papers presented at this conference provide guidelines for the design of livestock waste management systems. Topics discussed include waste collection, economics, lagoons, land application, methane generation, odor control, refeeding, runoff and storage, and waste treatment for stabilization. Twenty papers, dealing mostly with methane production, have been abstracted separately. 1166 references, 321 figures, 320 tables.

  15. Antibiotic use in livestock production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Antibiotic usage is a useful and commonly implemented practice in livestock and production agriculture that has progressively gained attention in recent years from consumers of animal products due to concerns about human and environmental health. Sub-therapeutic usage of antibiotics has led to a con...

  16. 25 CFR 167.15 - Control of livestock disease and introduction of livestock.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Control of livestock disease and introduction of livestock... NAVAJO GRAZING REGULATIONS § 167.15 Control of livestock disease and introduction of livestock. (a) The... contagious or infectious disease in the economic interest of the Navajo stock owners. Upon the...

  17. 9 CFR 309.11 - Vaccine livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Vaccine livestock. 309.11 Section 309.11 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION ANTE-MORTEM INSPECTION § 309.11 Vaccine livestock. Vaccine livestock with unhealed lesions...

  18. 9 CFR 309.11 - Vaccine livestock.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Vaccine livestock. 309.11 Section 309.11 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION ANTE-MORTEM INSPECTION § 309.11 Vaccine livestock. Vaccine livestock with unhealed lesions...

  19. 9 CFR 309.11 - Vaccine livestock.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Vaccine livestock. 309.11 Section 309.11 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION ANTE-MORTEM INSPECTION § 309.11 Vaccine livestock. Vaccine livestock with unhealed lesions...

  20. 9 CFR 309.11 - Vaccine livestock.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Vaccine livestock. 309.11 Section 309.11 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION ANTE-MORTEM INSPECTION § 309.11 Vaccine livestock. Vaccine livestock with unhealed lesions...

  1. 9 CFR 309.11 - Vaccine livestock.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Vaccine livestock. 309.11 Section 309.11 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION ANTE-MORTEM INSPECTION § 309.11 Vaccine livestock. Vaccine livestock with unhealed lesions...

  2. 25 CFR 700.77 - Livestock.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 2 2010-04-01 2010-04-01 false Livestock. 700.77 Section 700.77 Indians THE OFFICE OF NAVAJO AND HOPI INDIAN RELOCATION COMMISSION OPERATIONS AND RELOCATION PROCEDURES General Policies and Instructions Definitions § 700.77 Livestock. The term livestock shall mean all domesticated animals of...

  3. 7 CFR 205.237 - Livestock feed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.237 Livestock feed. (a) The producer of an organic livestock operation must provide livestock with a total feed...

  4. YA4-H! Youth Advocates for Health: Impact of a 4-H Teens-as-Teachers Program

    ERIC Educational Resources Information Center

    Arnold, Mary E.; Flesch, Jeffrey M.; Ashton, Carolyn; Black, Lynette; Brody, Barbara; Hosty, Maureen; Northway, Shanna

    2016-01-01

    This article reports the results of an evaluation of the YA4-H! Youth Advocates for Health--Teens as Teachers program. Consistent with previous research on the impact of teen teaching, the teens participating in the program gained confidence and skill with regard to teaching younger youths. The program also affected the teens' understanding that…

  5. Water Worlds. 4-H Member's Guide M-5-18; 4-H Leaders Guide L-5-18.

    ERIC Educational Resources Information Center

    Hawkes, Janet E.; And Others

    This pocket folder of materials is designed to provide children aged 9 to 12 with an opportunity to explore and observe aquatic environments. The package includes a 4-H Leader's guide, member's guide, and supplementary materials. The leader's guide contains safety considerations, tips and techniques, and additional activities for getting started…

  6. Litter Control Achievement - Ohio 4-H Club Score Sheet [and] Activity Guides 1 through 7. 4-H Pilot Program 918.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Cooperative Extension Service.

    Seven activity guides, evaluation sheet, and club scoresheet have been prepared for Ohio 4-H clubs' litter education program. Topics of the seven activity guides include: (1) general guidelines and types of activities; (2) little known facts about waste/litter; (3) guidelines for a walking tour; (4) fact sheet (questionnaire) related to garbage;…

  7. A Perfect Fit: 4-H Involvement for Youth with Disabilities. A Leader's Guide.

    ERIC Educational Resources Information Center

    Schnepf, Greg W.; And Others

    This guide for 4-H leaders and volunteers offers information to help integrate youth with disabilities into various 4-H programs. After an introduction, a section on 4-H and mainstreaming reviews the mission of 4-H; considers what 4-H has to offer youth; defines mainstreaming; notes the benefits of mainstreaming; and distinguishes among the terms…

  8. Climate change and broadacre livestock production across southern Australia. 1. Impacts of climate change on pasture and livestock productivity, and on sustainable levels of profitability.

    PubMed

    Moore, Andrew D; Ghahramani, Afshin

    2013-05-01

    Broadacre livestock production is a major but highly diverse component of agriculture in Australia that will be significantly exposed to predicted changes in climate over coming decades. We used the GRAZPLAN simulation models to assess the impacts of climate change under the SRES A2 scenario across southern Australia. Climate change impacts were examined across space (25 representative locations) and time (1970-99, 2030, 2050 and 2070 climate) for each of five livestock enterprises. Climate projection uncertainty was considered by analysing projections from four global circulation models (GCMs). Livestock production scenarios were compared at their profit-maximizing stocking rate, constrained to ensure that risks of soil erosion were acceptable. Impacts on net primary productivity (ANPP) varied widely between GCM projections; the average declines from historical climate were 9% in 2030, 7% in 2050 and 14% in 2070. Declines in ANPP were larger at lower-rainfall locations. Sensitivity of ANPP to changes in rainfall ranged from 0.4 to 1.7, to temperature increase from -0.15 to +0.07 °C(-1) and to CO2 increase from 0.11 to 0.32. At most locations the dry summer period lengthened, exacerbating the greater erosion risk due to lower ANPP. Transpiration efficiency of pastures increased by 6-25%, but the proportion of ANPP that could safely be consumed by livestock fell sharply so that operating profit (at constant prices) fell by an average of 27% in 2030, 32% in 2050 and 48% in 2070. This amplification of ANPP reductions into larger profitability declines is likely to generalize to other extensive livestock systems. Profit declines were most marked at drier locations, with operating losses expected at 9 of the 25 locations by 2070. Differences between livestock enterprises were smaller than differences between locations and dates. Future research into climate change impacts on Australian livestock production needs to emphasise the dry margin of the cereal-livestock zone.

  9. The changing role of shrubs in rangeland-based livestock production systems: Can shrubs increase our forage supply?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Projected global increases in ruminant numbers and loss of native grasslands will present a number of challenges for livestock agriculture. Escalated demand for livestock products may stimulate interest in using shrubs on western rangelands. A paradigm shift is needed to change the role of shrubs in...

  10. Eight challenges in modelling infectious livestock diseases.

    PubMed

    Brooks-Pollock, E; de Jong, M C M; Keeling, M J; Klinkenberg, D; Wood, J L N

    2015-03-01

    The transmission of infectious diseases of livestock does not differ in principle from disease transmission in any other animals, apart from that the aim of control is ultimately economic, with the influence of social, political and welfare constraints often poorly defined. Modelling of livestock diseases suffers simultaneously from a wealth and a lack of data. On the one hand, the ability to conduct transmission experiments, detailed within-host studies and track individual animals between geocoded locations make livestock diseases a particularly rich potential source of realistic data for illuminating biological mechanisms of transmission and conducting explicit analyses of contact networks. On the other hand, scarcity of funding, as compared to human diseases, often results in incomplete and partial data for many livestock diseases and regions of the world. In this overview of challenges in livestock disease modelling, we highlight eight areas unique to livestock that, if addressed, would mark major progress in the area.

  11. Leakage currents in 4H-SiC JBS diodes

    SciTech Connect

    Ivanov, P. A. Grekhov, I. V.; Potapov, A. S.; Kon'kov, O. I.; Il'inskaya, N. D.; Samsonova, T. P.; Korol'kov, O.; Sleptsuk, N.

    2012-03-15

    Leakage currents in high-voltage 4H-SiC diodes, which have an integrated (p-n) Schottky structure (Junction Barrier Schottky, JBS), have been studied using commercial diodes and specially fabricated (based on a commercial epitaxial material) test Schottky diodes with and without the JBS structure. It is shown that (i) the main role in reverse charge transport is played by SiC crystal structure defects, most probably, by threading dislocations (density {approx}10{sup 4} cm{sup -2}), and (ii) the JBS structure, formed by the implantation of boron, partially suppresses the leakage currents (by up to a factor of 10 at optimal separation, 8 {mu}m between local p-type regions).

  12. Extended defects in 4H-silicon carbide homoepitaxial layers

    NASA Astrophysics Data System (ADS)

    Zhang, Xuan

    The purpose of this thesis is to study the structure of extended defects in 4H-SIC homoepitaxial layers, and to identify their nucleation mechanisms. Characteristics of basal plane dislocations in 4H-SiC epilayers were investigated in a comprehensive manner, including their morphologies, Burgers' vectors, positions, and correlation with the extended defects propagating from the substrate. Plan-view transmission x-ray topography was the major characterization technique used in this study. Complementary data was obtained by KOH etching and optical microscopy. Trace of glide was detected on every basal plane dislocation in the entire 3-inch epilayer. In the center area of the epi-wafer, the glide can extend to macroscopic distance and form edge-type dislocations at the epilayer/surface interface. During the motion, dislocation half loop arrays were found to nucleate at the growth front. The magnitude of the resolved shear stress was estimated based on the radius of curvature of the dislocation lines. It surpassed the critical resolved shear stress at the epitaxial growth temperature. The stress was identified to be compressive in the epilayer. Its origin was studied. Nitrogen-doping-difference-induced misfit strain was excluded as the source of the stress. The structures of two morphological defects, 'carrots' and 'arrows', were studied. Cross-section x-ray topography was used to image the structure of carrot defect in whole. The defect was found to nucleate at the epilayer/substrate interface on a threading screw dislocation propagating from the substrate. Its structure was mainly composed of a prismatic stacking fault and a Frank-type basal plane stacking fault. The arrow defect was found to be produced by a spheroid shape inclusion in the volume of the epilayer. Zone axis diffraction pattern under transmission electron microscope identified the nature of the inclusion as 3C-SIC. It was determined to nucleate at the substrate surface contaminations.

  13. 25 CFR 167.15 - Control of livestock disease and introduction of livestock.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Control of livestock disease and introduction of... NAVAJO GRAZING REGULATIONS § 167.15 Control of livestock disease and introduction of livestock. (a) The... contagious or infectious disease in the economic interest of the Navajo stock owners. Upon the...

  14. 25 CFR 167.15 - Control of livestock disease and introduction of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Control of livestock disease and introduction of... NAVAJO GRAZING REGULATIONS § 167.15 Control of livestock disease and introduction of livestock. (a) The... contagious or infectious disease in the economic interest of the Navajo stock owners. Upon the...

  15. 25 CFR 167.15 - Control of livestock disease and introduction of livestock.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Control of livestock disease and introduction of... NAVAJO GRAZING REGULATIONS § 167.15 Control of livestock disease and introduction of livestock. (a) The... contagious or infectious disease in the economic interest of the Navajo stock owners. Upon the...

  16. 25 CFR 167.15 - Control of livestock disease and introduction of livestock.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Control of livestock disease and introduction of... NAVAJO GRAZING REGULATIONS § 167.15 Control of livestock disease and introduction of livestock. (a) The... contagious or infectious disease in the economic interest of the Navajo stock owners. Upon the...

  17. Effects of Wolf Mortality on Livestock Depredations

    PubMed Central

    Wielgus, Robert B.; Peebles, Kaylie A.

    2014-01-01

    Predator control and sport hunting are often used to reduce predator populations and livestock depredations, – but the efficacy of lethal control has rarely been tested. We assessed the effects of wolf mortality on reducing livestock depredations in Idaho, Montana and Wyoming from 1987–2012 using a 25 year time series. The number of livestock depredated, livestock populations, wolf population estimates, number of breeding pairs, and wolves killed were calculated for the wolf-occupied area of each state for each year. The data were then analyzed using a negative binomial generalized linear model to test for the expected negative relationship between the number of livestock depredated in the current year and the number of wolves controlled the previous year. We found that the number of livestock depredated was positively associated with the number of livestock and the number of breeding pairs. However, we also found that the number of livestock depredated the following year was positively, not negatively, associated with the number of wolves killed the previous year. The odds of livestock depredations increased 4% for sheep and 5–6% for cattle with increased wolf control - up until wolf mortality exceeded the mean intrinsic growth rate of wolves at 25%. Possible reasons for the increased livestock depredations at ≤25% mortality may be compensatory increased breeding pairs and numbers of wolves following increased mortality. After mortality exceeded 25%, the total number of breeding pairs, wolves, and livestock depredations declined. However, mortality rates exceeding 25% are unsustainable over the long term. Lethal control of individual depredating wolves may sometimes necessary to stop depredations in the near-term, but we recommend that non-lethal alternatives also be considered. PMID:25470821

  18. Mapping the Global Distribution of Livestock

    PubMed Central

    Robinson, Timothy P.; Wint, G. R. William; Conchedda, Giulia; Van Boeckel, Thomas P.; Ercoli, Valentina; Palamara, Elisa; Cinardi, Giuseppina; D'Aietti, Laura; Hay, Simon I.; Gilbert, Marius

    2014-01-01

    Livestock contributes directly to the livelihoods and food security of almost a billion people and affects the diet and health of many more. With estimated standing populations of 1.43 billion cattle, 1.87 billion sheep and goats, 0.98 billion pigs, and 19.60 billion chickens, reliable and accessible information on the distribution and abundance of livestock is needed for a many reasons. These include analyses of the social and economic aspects of the livestock sector; the environmental impacts of livestock such as the production and management of waste, greenhouse gas emissions and livestock-related land-use change; and large-scale public health and epidemiological investigations. The Gridded Livestock of the World (GLW) database, produced in 2007, provided modelled livestock densities of the world, adjusted to match official (FAOSTAT) national estimates for the reference year 2005, at a spatial resolution of 3 minutes of arc (about 5×5 km at the equator). Recent methodological improvements have significantly enhanced these distributions: more up-to date and detailed sub-national livestock statistics have been collected; a new, higher resolution set of predictor variables is used; and the analytical procedure has been revised and extended to include a more systematic assessment of model accuracy and the representation of uncertainties associated with the predictions. This paper describes the current approach in detail and presents new global distribution maps at 1 km resolution for cattle, pigs and chickens, and a partial distribution map for ducks. These digital layers are made publically available via the Livestock Geo-Wiki (http://www.livestock.geo-wiki.org), as will be the maps of other livestock types as they are produced. PMID:24875496

  19. Chloride-based fast homoepitaxial growth of 4H-SiC films in a vertical hot-wall CVD

    NASA Astrophysics Data System (ADS)

    Guoguo, Yan; Feng, Zhang; Yingxi, Niu; Fei, Yang; Xingfang, Liu; Lei, Wang; Wanshun, Zhao; Guosheng, Sun; Yiping, Zeng

    2016-06-01

    Chloride-based fast homoepitaxial growth of 4H-SiC epilayers was performed on 4° off-axis 4H-SiC substrates in a home-made vertical hot-wall chemical vapor deposition (CVD) system using H2-SiH4-C2H4-HCl. The effect of the SiH4/H2 ratio and reactor pressure on the growth rate of 4H-SiC epilayers has been studied successively. The growth rate increase in proportion to the SiH4/H2 ratio and the influence mechanism of chlorine has been investigated. With the reactor pressure increasing from 40 to 100 Torr, the growth rate increased to 52 μm/hand then decreased to 47 μm/h, which is due to the joint effect of H2 and HCl etching as well as the formation of Si clusters at higher reactor pressure. The surface root mean square (RMS) roughness keeps around 1 nm with the growth rate increasing to 49 μm/h. The scanning electron microscope (SEM), Raman spectroscopy and X-ray diffraction (XRD) demonstrate that 96.7 μm thick 4H-SiC layers of good uniformity in thickness and doping with high crystal quality can be achieved. These results prove that chloride-based fast epitaxy is an advanced growth technique for 4H-SiC homoepitaxy. Project supported by the National High Technology R&D Program of China (No. 2014AA041402), the National Natural Science Foundation of China (Nos. 61474113, 61274007, 61574140), the Beijing Natural Science Foundation of China (Nos. 4132076, 4132074), the Program of State Grid Smart Grid Research Institute (No. SGRI-WD-71-14-004), and the Youth Innovation Promotion Association of CAS.

  20. 7 CFR 760.304 - Covered livestock.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., sheep, or swine; (2) Be livestock that would normally have been grazing the eligible grazing land or pastureland in the county: (i) During the normal grazing period for the specific type of grazing land or... using the managed rangeland for grazing due to a fire; (3) Be livestock that the eligible...

  1. 7 CFR 760.304 - Covered livestock.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., sheep, or swine; (2) Be livestock that would normally have been grazing the eligible grazing land or pastureland in the county: (i) During the normal grazing period for the specific type of grazing land or... using the managed rangeland for grazing due to a fire; (3) Be livestock that the eligible...

  2. 7 CFR 760.304 - Covered livestock.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., sheep, or swine; (2) Be livestock that would normally have been grazing the eligible grazing land or pastureland in the county: (i) During the normal grazing period for the specific type of grazing land or... using the managed rangeland for grazing due to a fire; (3) Be livestock that the eligible...

  3. 7 CFR 760.304 - Covered livestock.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., sheep, or swine; (2) Be livestock that would normally have been grazing the eligible grazing land or pastureland in the county: (i) During the normal grazing period for the specific type of grazing land or... using the managed rangeland for grazing due to a fire; (3) Be livestock that the eligible...

  4. Chapter 2: Livestock and Grazed Lands Emissions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A total of 342 MMT CO2 eq. of greenhouse gasses (GHGs) were emitted from livestock, managed livestock waste, and grazed land in 2013. This represents about 66% of total emissions from the agricultural sector, which totaled 516 MMT CO2 eq. Compared to the base line year (1990), emissions from livesto...

  5. 50 CFR 35.9 - Livestock grazing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Livestock grazing. 35.9 Section 35.9 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE... grazing. (a) The grazing of livestock, where established prior to the date of legislation which...

  6. 50 CFR 35.9 - Livestock grazing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Livestock grazing. 35.9 Section 35.9 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR (CONTINUED) THE... grazing. (a) The grazing of livestock, where established prior to the date of legislation which...

  7. Livestock waste-to-energy opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of animal manure and other organic-based livestock wastes as feedstocks for waste-to-energy production has the potential to convert the livestock waste treatment from a liability into a profit center that can generate annual revenues and diversify farm income. This presentation introduces tw...

  8. Anaerobic digestion of livestock manures: A current opportunities casebook

    SciTech Connect

    Lusk, P.D.

    1995-08-01

    Growth and concentration of the livestock industry creates new opportunities for proper disposal of the large quantities of manures generated at dairy, swine, and poultry farms. One manure management system provides not only pollution prevention but also converts a problem into a new profit center. Economic evaluations and case studies of operating systems indicate that the anaerobic digestion of livestock manures is a commercially-available bioconversion technology with considerable potential for providing profitable co-products, including a renewable fuel. An introduction to the engineering economies of these technologies is provided, based on estimates of digesters that generate electricity from the recovered methane. Regression models used to estimate digester cost and internal rate of return are developed from the evaluations. Case studies of operating digesters, including project and maintenance histories, and the operator`s {open_quotes}lessons learned{close_quotes}, are provided as a reality check.

  9. Stable Relationships: Horse Care Activities. Level 3. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08055

    ERIC Educational Resources Information Center

    Neiberger-Miller, Ami

    2004-01-01

    This is the third in a series of five horse project activity guides for youth. Levels 1-3 focus on "horse-less" activities, while Levels 4 and 5 zero in on riding and horsemanship. Each guide has an achievement program to encourage youth to learn and develop life skills. The assistance of a horse project helper in completing the achievement…

  10. 7 CFR 205.239 - Livestock living conditions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.239 Livestock living conditions. (a) The producer of an organic livestock operation must establish and maintain livestock...

  11. Agent Based Model of Livestock Movements

    NASA Astrophysics Data System (ADS)

    Miron, D. J.; Emelyanova, I. V.; Donald, G. E.; Garner, G. M.

    The modelling of livestock movements within Australia is of national importance for the purposes of the management and control of exotic disease spread, infrastructure development and the economic forecasting of livestock markets. In this paper an agent based model for the forecasting of livestock movements is presented. This models livestock movements from farm to farm through a saleyard. The decision of farmers to sell or buy cattle is often complex and involves many factors such as climate forecast, commodity prices, the type of farm enterprise, the number of animals available and associated off-shore effects. In this model the farm agent's intelligence is implemented using a fuzzy decision tree that utilises two of these factors. These two factors are the livestock price fetched at the last sale and the number of stock on the farm. On each iteration of the model farms choose either to buy, sell or abstain from the market thus creating an artificial supply and demand. The buyers and sellers then congregate at the saleyard where livestock are auctioned using a second price sealed bid. The price time series output by the model exhibits properties similar to those found in real livestock markets.

  12. Livestock production: recent trends, future prospects

    PubMed Central

    Thornton, Philip K.

    2010-01-01

    The livestock sector globally is highly dynamic. In developing countries, it is evolving in response to rapidly increasing demand for livestock products. In developed countries, demand for livestock products is stagnating, while many production systems are increasing their efficiency and environmental sustainability. Historical changes in the demand for livestock products have been largely driven by human population growth, income growth and urbanization and the production response in different livestock systems has been associated with science and technology as well as increases in animal numbers. In the future, production will increasingly be affected by competition for natural resources, particularly land and water, competition between food and feed and by the need to operate in a carbon-constrained economy. Developments in breeding, nutrition and animal health will continue to contribute to increasing potential production and further efficiency and genetic gains. Livestock production is likely to be increasingly affected by carbon constraints and environmental and animal welfare legislation. Demand for livestock products in the future could be heavily moderated by socio-economic factors such as human health concerns and changing socio-cultural values. There is considerable uncertainty as to how these factors will play out in different regions of the world in the coming decades. PMID:20713389

  13. A New Vision--4-H Work with Disadvantaged Youth.

    ERIC Educational Resources Information Center

    Purdue Univ., Lafayette, IN. Cooperative Extension Service.

    Extension low income programs in Indiana, part of the nation-wide Expanded Food and Nutrition Program, are described. The programs were carried out in 11 areas of the State. The types of programs varied from community, ranging from day camps, camping, arts and crafts, hikes, gardening, and health and nutrition projects. Youngsters from 5 to 15…

  14. Composting: Wastes to Resources. 4-H Leader's/Teacher's Guide.

    ERIC Educational Resources Information Center

    Bonhotal, Jean F.; Krasny, Marianne E.

    This guide is designed for adult volunteer leaders, camp counselors, and teachers who want to set up composting projects with youth. Five sections explore: (1) an introduction to composting with illustrated instructions for making compost; (2) different methods of composting and structures needed for various composting systems; (3) how to identify…

  15. Towards sustainability in the extensive and intensive livestock sectors.

    PubMed

    Niamir-Fuller, M

    2016-11-01

    An increase in both human population and economic growth has been accompanied by rising per capita demand for animal products. The livestock industry is under pressure to meet this demand, but its current patterns of production are not environmentally sustainable, causing negative health impacts on humans and raising welfare concerns for animals. With little regulation of the intensive livestock sector in most countries, animal products are available at cheaper prices on consumer markets, undercutting more sustainable production systems, such as those used by pastoralists and organic farmers. Other beneficial aspects of sustainable intensification and sustainable pastoralism should also be taken into account. However, it is unclear whether moving towards sustainable animal husbandry (both intensive and extensive) will meet the projected demand from nine billion people in 2030, unless attention is also paid to fairer and more responsible consumption. This paper proposes a conceptual framework to transform the livestock sector, using principles of sustainable consumption and production, environmental stewardship, inclusive prosperity, and healthy lifestyles. It also highlights several areas where additional research and modelling are required.

  16. ZC4H2, an XLID gene, is required for the generation of a specific subset of CNS interneurons

    PubMed Central

    May, Melanie; Hwang, Kyu-Seok; Miles, Judith; Williams, Charlie; Niranjan, Tejasvi; Kahler, Stephen G.; Chiurazzi, Pietro; Steindl, Katharina; Van Der Spek, Peter J.; Swagemakers, Sigrid; Mueller, Jennifer; Stefl, Shannon; Alexov, Emil; Ryu, Jeong-Im; Choi, Jung-Hwa; Kim, Hyun-Taek; Tarpey, Patrick; Neri, Giovanni; Holloway, Lynda; Skinner, Cindy; Stevenson, Roger E.; Dorsky, Richard I.; Wang, Tao; Schwartz, Charles E.; Kim, Cheol-Hee

    2015-01-01

    Miles–Carpenter syndrome (MCS) was described in 1991 as an XLID syndrome with fingertip arches and contractures and mapped to proximal Xq. Patients had microcephaly, short stature, mild spasticity, thoracic scoliosis, hyperextendable MCP joints, rocker-bottom feet, hyperextended elbows and knees. A mutation, p.L66H, in ZC4H2, was identified in a XLID re-sequencing project. Additional screening of linked families and next generation sequencing of XLID families identified three ZC4H2 mutations: p.R18K, p.R213W and p.V75in15aa. The families shared some relevant clinical features. In silico modeling of the mutant proteins indicated all alterations would destabilize the protein. Knockout mutations in zc4h2 were created in zebrafish and homozygous mutant larvae exhibited abnormal swimming, increased twitching, defective eye movement and pectoral fin contractures. Because several of the behavioral defects were consistent with hyperactivity, we examined the underlying neuronal defects and found that sensory neurons and motoneurons appeared normal. However, we observed a striking reduction in GABAergic interneurons. Analysis of cell-type-specific markers showed a specific loss of V2 interneurons in the brain and spinal cord, likely arising from mis-specification of neural progenitors. Injected human wt ZC4H2 rescued the mutant phenotype. Mutant zebrafish injected with human p.L66H or p.R213W mRNA failed to be rescued, while the p.R18K mRNA was able to rescue the interneuron defect. Our findings clearly support ZC4H2 as a novel XLID gene with a required function in interneuron development. Loss of function of ZC4H2 thus likely results in altered connectivity of many brain and spinal circuits. PMID:26056227

  17. ZC4H2, an XLID gene, is required for the generation of a specific subset of CNS interneurons.

    PubMed

    May, Melanie; Hwang, Kyu-Seok; Miles, Judith; Williams, Charlie; Niranjan, Tejasvi; Kahler, Stephen G; Chiurazzi, Pietro; Steindl, Katharina; Van Der Spek, Peter J; Swagemakers, Sigrid; Mueller, Jennifer; Stefl, Shannon; Alexov, Emil; Ryu, Jeong-Im; Choi, Jung-Hwa; Kim, Hyun-Taek; Tarpey, Patrick; Neri, Giovanni; Holloway, Lynda; Skinner, Cindy; Stevenson, Roger E; Dorsky, Richard I; Wang, Tao; Schwartz, Charles E; Kim, Cheol-Hee

    2015-09-01

    Miles-Carpenter syndrome (MCS) was described in 1991 as an XLID syndrome with fingertip arches and contractures and mapped to proximal Xq. Patients had microcephaly, short stature, mild spasticity, thoracic scoliosis, hyperextendable MCP joints, rocker-bottom feet, hyperextended elbows and knees. A mutation, p.L66H, in ZC4H2, was identified in a XLID re-sequencing project. Additional screening of linked families and next generation sequencing of XLID families identified three ZC4H2 mutations: p.R18K, p.R213W and p.V75in15aa. The families shared some relevant clinical features. In silico modeling of the mutant proteins indicated all alterations would destabilize the protein. Knockout mutations in zc4h2 were created in zebrafish and homozygous mutant larvae exhibited abnormal swimming, increased twitching, defective eye movement and pectoral fin contractures. Because several of the behavioral defects were consistent with hyperactivity, we examined the underlying neuronal defects and found that sensory neurons and motoneurons appeared normal. However, we observed a striking reduction in GABAergic interneurons. Analysis of cell-type-specific markers showed a specific loss of V2 interneurons in the brain and spinal cord, likely arising from mis-specification of neural progenitors. Injected human wt ZC4H2 rescued the mutant phenotype. Mutant zebrafish injected with human p.L66H or p.R213W mRNA failed to be rescued, while the p.R18K mRNA was able to rescue the interneuron defect. Our findings clearly support ZC4H2 as a novel XLID gene with a required function in interneuron development. Loss of function of ZC4H2 thus likely results in altered connectivity of many brain and spinal circuits.

  18. High current gain 4H-SiC bipolar junction transistor

    NASA Astrophysics Data System (ADS)

    Yourun, Zhang; Jinfei, Shi; Ying, Liu; Chengchun, Sun; Fei, Guo; Bo, Zhang

    2016-04-01

    A novel 4H-SiC BJT of high current gain with a suppressing surface traps effect has been proposed. It is effective to improve the current gain due to the lower electrons density in the surface region by extending the emitter metal to overlap the passivation layer on the extrinsic base surface. The electrons trapped in the extrinsic base surface induce the degeneration of SiC BJTs device performance. By modulating the electron recombination rate, the novel structure can increase the current gain to 63.2% compared with conventional ones with the compatible process technology. Optimized sizes are an overlapped metal length of 4 μm, as well as an oxide layer thickness of 50 nm. Project supported by the National Natural Science Foundation of China (Nos. 61306093, 61401075).

  19. Exposure Assessment of Livestock Carcass Management ...

    EPA Pesticide Factsheets

    Report This report describes relative exposures and hazards for different livestock carcass management options in the event of a natural disaster. A quantitative exposure assessment by which livestock carcass management options are ranked relative to one another for a hypothetical site setting, a standardized set of environmental conditions (e.g., meteorology), and following a single set of assumptions about how the carcass management options are designed and implemented. These settings, conditions, and assumptions are not necessarily representative of site-specific carcass management efforts. Therefore, the exposure assessment should not be interpreted as estimating levels of chemical and microbial exposure that can be expected to result from the management options evaluated. The intent of the relative rankings is to support scientifically-based livestock carcass management decisions that consider potential hazards to human health, livestock, and the environment. This exposure assessment also provides information to support choices about mitigation measures to minimize or eliminate specific exposure pathways.

  20. Adapting livestock behaviour to achieve management goals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using livestock to efficiently achieve management goals requires melding animal behavior with mechanical and electronic equipment. Practices such as autonomously obtaining individual animal liveweight when combined with individual animal electronic identification can produce numerous cost saving ad...

  1. The ultraviolet photochemistry of diacetylene - Direct detection of primary products of the metastable C4H2* + C4H2 reaction

    NASA Technical Reports Server (NTRS)

    Bandy, Ralph E.; Lakshminarayan, Chitra; Frost, Rex K.; Zwier, Timothy S.

    1993-01-01

    The products of diacetylene's ultraviolet photochemistry over the 245-220 nm region were directly determined in experiments where C4H2 was excited within a small reaction tube attached to a pulsed nozzle. The products formed in the collisions of C4H2* with C4H2 were subsequently ionized by vacuum UV radiation (at 118 nm) in the ion source of a time-of-flight mass spectrometer. It was found that the reaction of C4H2* with C4H2 produces C6H2 (+C2H2), C8H2 (+2H,H2), and C8H3 (+H), confirming the results of Glicker and Okabe (1987). Under certain conditions, secondary products were observed. Mechanisms for the observed reactions are proposed.

  2. Perceptions of Missouri 4-H Youth Development Personnel Regarding Interorganizational Cooperative Behavior

    ERIC Educational Resources Information Center

    McKim, Billy R.; Torres, Robert M.

    2011-01-01

    Perceptions of 4-H youth development personnel regarding interorganizational cooperation were studied between the perceived and desired levels of cooperative activities between 4-H youth development personnel and secondary agriculture teachers. Results indicated that 4-H youth development personnel wanted higher levels of coordinated efforts…

  3. Using the Delphi Technique to Assess Educational Needs Related to Extension's 4-H Beef Program.

    ERIC Educational Resources Information Center

    Shih, Ching-Chun; Gamon, Julia A.

    1997-01-01

    Delphi panels completing questionnaires included 32 parents of 4-H students, 16 extension beef specialists, 21 4-H field specialists, and 21 industry representatives. They identified 31 subject-matter and 30 life-skill topics useful for 4-H manuals. Emerging topics included consumer and environmental concerns. (SK)

  4. Examination of Attitude and Interest Measures for 4-H Science Evaluation

    ERIC Educational Resources Information Center

    Lewis, Kendra M.; Worker, Steven M.

    2015-01-01

    Science education research has demonstrated the influence of affect on learning. The National 4-H Science Logic Model outlines outcomes from youth participation in 4-H science programs, which includes attitude and interest outcomes. The associated measure, the National 4-H Science Common Measure, assesses these attitude constructs and not other…

  5. Expression analysis of kenaf cinnamate 4-hydroxylase (C4H) ortholog during developmental and stress responses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to clone and analyze the expression pattern of a C4H gene encoding cinnamate 4-hydroxylase from kenaf (Hibiscus cannabinus L.). A full-length C4H ortholog was cloned using degenerate primers and the RACE (rapid amplification of cDNA ends) method. The full-length C4H ortholog...

  6. Understanding the Knowledge and Use of Experiential Learning within Pennsylvania 4-H Clubs

    ERIC Educational Resources Information Center

    Bechtel, Robyn; Ewing, John C.; Threeton, Mark; Mincemoyer, Claudia

    2013-01-01

    Experiential learning is incorporated into the National 4-H curriculum. However, the state 4-H staff in Pennsylvania is unsure of the current knowledge and use of experiential learning within the local 4-H clubs. An online survey was distributed to Extension educators and volunteer leaders within Pennsylvania to assess the current knowledge and…

  7. Stewardship as a Means to Create Organizational Reform: A View into Minnesota 4-H Youth Development

    ERIC Educational Resources Information Center

    Skuza, Jennifer A.; Freeman, Dorothy M.; Bremseth, Tamara J.; Doering, Shirley A.; Quinlan, Robert B.; Morreim, Patricia A.; Deidrick, James C.

    2010-01-01

    Minnesota 4-H Youth Development (MN 4-H) used stewardship as a means to create organizational reform to address the public use of the 4-H name and emblem in terms of risk management, real estate and equipment, and finances. A task force implemented a participatory process with colleagues and stakeholders to build and implement the reform effort.…

  8. Livestock policy and trade issues in SADC.

    PubMed

    Hulman, B

    2009-03-01

    As from 2001, the Southern African Development Community (SADC) has embarked on a course to deepen regional integration through restructuring. Under the new structure SADC has centralised the coordination of its activities to the Secretariat in Gaborone. The former Sector Coordinating Units have been merged into four directorates, one of which is the Food, Agriculture and Natural Resources (FANR) Directorate, which comprises, amongst others, the Livestock Development Unit (LDU). The LDU, under the aegis of the FANR, formulates policies for regional livestock development in order to respond to the objectives of the Regional Indicative Strategic Development Plan (RISDP), and which are mainly to: Contribute to improved food security, Promote wealth creation, Enhance rural livelihood, Enhance livestock as a tradable and consumable commodity. Following the launch of the SADC Economic Partnership Agreement (EPA) negotiations, the eight SADC EPA member states identified sanitary and phytosanitary and technical barriers to trade to be major trade barriers for access to international markets, especially the EU market where standards are normally set beyond international standards. SADC has already brought some of the issues related to beef exports to the OIE Regional Commission for Africa as SADC member states feel that a few of the present requirements do not have a scientific basis. The paper discusses the process that the LDU follows in the formulation of policies and strategies in regional livestock development with the objective of bolstering intra and extra regional trade in livestock and livestock products.

  9. 36 CFR 293.7 - Grazing of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 2 2010-07-01 2010-07-01 false Grazing of livestock. 293.7...-PRIMITIVE AREAS § 293.7 Grazing of livestock. (a) The grazing of livestock, where such use was established..., shall be permitted to continue under the general regulations covering grazing of livestock on...

  10. 36 CFR 293.7 - Grazing of livestock.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 2 2011-07-01 2011-07-01 false Grazing of livestock. 293.7...-PRIMITIVE AREAS § 293.7 Grazing of livestock. (a) The grazing of livestock, where such use was established..., shall be permitted to continue under the general regulations covering grazing of livestock on...

  11. 9 CFR 313.2 - Handling of livestock.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Handling of livestock. 313.2 Section 313.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.2 Handling of livestock. (a) Driving of livestock from...

  12. 9 CFR 313.2 - Handling of livestock.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Handling of livestock. 313.2 Section 313.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.2 Handling of livestock. (a) Driving of livestock from...

  13. 9 CFR 313.2 - Handling of livestock.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Handling of livestock. 313.2 Section 313.2 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.2 Handling of livestock. (a) Driving of livestock from...

  14. 29 CFR 780.615 - Raising of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Raising of livestock. 780.615 Section 780.615 Labor... Agriculture and Livestock Auction Operations Under the Section 13(b)(13) Exemption Requirements for Exemption § 780.615 Raising of livestock. Livestock auction operations are within the 13(b)(13) exemption...

  15. 29 CFR 780.616 - Operations included in raising livestock.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Operations included in raising livestock. 780.616 Section... Employment in Agriculture and Livestock Auction Operations Under the Section 13(b)(13) Exemption Requirements for Exemption § 780.616 Operations included in raising livestock. Raising livestock includes...

  16. 9 CFR 85.4 - Interstate movement of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Interstate movement of livestock. 85.4... Interstate movement of livestock. (a) Livestock showing clinical evidence of pseudorabies shall not be moved interstate. (b) Livestock that have been exposed to an animal showing clinical evidence of pseudorabies...

  17. 29 CFR 780.617 - Adjunct livestock auction operations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Adjunct livestock auction operations. 780.617 Section 780... Employment in Agriculture and Livestock Auction Operations Under the Section 13(b)(13) Exemption Requirements for Exemption § 780.617 Adjunct livestock auction operations. The livestock auction...

  18. Towards a sustainable livestock production in developing countries and the importance of animal health strategy therein.

    PubMed

    Kaasschieter, G A; de Jong, R; Schiere, J B; Zwart, D

    1992-04-01

    Livestock and animal health development projects have not always led to substantial increases in animal productivity or in farmers' welfare. Some have even resulted in unsustainable systems, when they were not based on an understanding of (livestock) production systems. The multipurpose functions of livestock and complex relationships between the biological, technical and social components require a systems approach, whereby nutrition, animal health, breeding, biotechnology knowhow, inputs and technologies are used to optimise resource use. The challenge for developed and developing countries is to reverse the current degradation of the environment, and arrive at sustainable increases in crop and livestock production to secure present and future food supplies. For rural development, governments should show long term commitment and political will to support the rural population in development programmes, because smallholders (including women and landless livestock keepers) represent a large labour force in developing countries. Different systems need different approaches. Pastoral systems must focus on effective management of grazing pressure of the rangelands. Communal rangelands management involves not only the development and application of technologies (e.g. feedlots, vaccination campaigns), but also land tenure policies, institutional development, economic return and a reduction in the number of people depending upon livestock. Smallholder mixed farms must aim at intensification of the total production system, in which external inputs are indispensable, but with the emphasis on optimum input-output relationships by reducing resource losses due to poor management. Resource-poor farming systems must aim at the improved management of the various livestock species in backyards and very small farms, and proper packages for cattle, buffaloes, sheep, goats, rabbits and poultry should be developed. Specialised commercial livestock farming systems (poultry, pigs, dairy

  19. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  20. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  1. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  2. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  3. 9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Livestock affected with anthrax... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways. (a) Any livestock found on ante-mortem inspection to be affected with anthrax shall be...

  4. Volunteer Educators' Influence on Youth Participation and Learning in 4-H STEM Learning by Design Programs

    NASA Astrophysics Data System (ADS)

    Worker, Steven Michael

    The purpose of this study was to describe the co-construction of three 4-H STEM (science, technology, engineering, and mathematics) learning by design programs by volunteer educators and youth participants in the 4-H Youth Development Program. The programs advanced STEM learning through design, a pedagogical approach to support youth in planning, designing, and making shareable artifacts. This pedagogical approach is a special case of project-based learning, related to the practices found in the science learning through design literature as well as the making and tinkering movements. Specifically, I explored adult volunteer educators' roles and pedagogical strategies implementing the 4-H Junk Drawer Robotics curriculum (Mahacek, Worker, and Mahacek, 2011) and how that, in turn, afforded and constrained opportunities for youth to display or report engagement in design practices; learning of STEM content; strengthening tool competencies; dispositions of resilience, reciprocity, and playfulness; and psychological ownership. The curriculum targeted middle school youth with a sequence of science inquiry activities and engineering design challenges. This study employed naturalist and multiple-case study methodology relying on participant observations and video, interviews with educators, and focus groups with youth within three 4-H educational robotics programs organized by adult 4-H volunteer educators. Data collection took place in 2014 and 2015 at Santa Clara with an educator and seven youth; Solano with three educators and eight youth; and Alameda with an educator and seven youth. Data analysis revealed six discrete categories of pedagogy and interactions that I labeled as participation structures that included lecture, demonstration, learning activity, group sharing, scripted build, and design & build. These participation structures were related to the observed pedagogical practices employed by the educators. There was evidence of youth engagement in design

  5. Quantifying Livestock Heat Stress Impacts in the Sahel

    NASA Astrophysics Data System (ADS)

    Broman, D.; Rajagopalan, B.; Hopson, T. M.

    2014-12-01

    Livestock heat stress, especially in regions of the developing world with limited adaptive capacity, has a largely unquantified impact on food supply. Though dominated by ambient air temperature, relative humidity, wind speed, and solar radiation all affect heat stress, which can decrease livestock growth, milk production, reproduction rates, and mortality. Indices like the thermal-humidity index (THI) are used to quantify the heat stress experienced from climate variables. Livestock experience differing impacts at different index critical thresholds that are empirically determined and specific to species and breed. This lack of understanding has been highlighted in several studies with a limited knowledge of the critical thresholds of heat stress in native livestock breeds, as well as the current and future impact of heat stress,. As adaptation and mitigation strategies to climate change depend on a solid quantitative foundation, this knowledge gap has limited such efforts. To address the lack of study, we have investigated heat stress impacts in the pastoral system of Sub-Saharan West Africa. We used a stochastic weather generator to quantify both the historic and future variability of heat stress. This approach models temperature, relative humidity, and precipitation, the climate variables controlling heat stress. Incorporating large-scale climate as covariates into this framework provides a better historical fit and allows us to include future CMIP5 GCM projections to examine the climate change impacts on heat stress. Health and production data allow us to examine the influence of this variability on livestock directly, and are considered in conjunction with the confounding impacts of fodder and water access. This understanding provides useful information to decision makers looking to mitigate the impacts of climate change and can provide useful seasonal forecasts of heat stress risk. A comparison of the current and future heat stress conditions based on

  6. The reinvestigation of the kinetics of the metathesis reactions t-C4H9• + HBr (HI) → i-C4H10 + Br• (I•) and of the t-C4H9• free radical thermochemistry.

    PubMed

    Leplat, N; Rossi, M J

    2014-07-17

    A reinvestigation of the absolute rate constant of the metathesis reactions t-C4H9• + HBr → i-C4H10 + Br• (1) and t-C4H9• + HI → i-C4H10 + I• (2) was performed thanks to a recently developed apparatus consisting of a Knudsen reactor coupled to detection based on single-photon (VUV) photoionization mass spectrometry (SPIMS). It enables the generation of thermalized hydrocarbon free radicals owing to a source upstream of and external to the Knudsen reactor. The following Arrhenius expressions were obtained: k1 = 5.6(±1.4) × 10(–12) exp(−6.76(±0.94)/(RT)) and k2 = 2.0(±0.6) × 10(–11) exp(−8.48(±0.94)/(RT)) with R = 8.314 J mol(–1) K(–1) over the range 293 to 623 K. The mass balance of the reaction system based on closed shell product detection (CSPD) was checked in order to ensure the accuracy of the used reaction mechanism and as an independent check of k1 and k2. The wall-loss rate constants of the t-butyl free radical, kw(C4H9), were measured and found to be low compared with the corresponding escape rate constant, ke(C4H9), for effusion of t-C4H9• out of the Knudsen reactor. On the basis of the present results, the free radical standard heat of formation ΔfH298°(t-C4H9•) = 44.3 ± 1.7 kJ mol(–1) was obtained when combined with the kinetics of the inverse halogenation reaction taken from the literature and using S298°(t-C4H9•) = 322.2 J K(–1) mol(–1) following a “Third Law” evaluation method. The standard enthalpy for t-butyl free radical is consistent for both the bromination and iodination reactions within the stated uncertainties.

  7. Dzuds, droughts, and livestock mortality in Mongolia

    NASA Astrophysics Data System (ADS)

    Palat Rao, Mukund; Davi, Nicole K.; D'Arrigo, Rosanne D.; Skees, Jerry; Nachin, Baatarbileg; Leland, Caroline; Lyon, Bradfield; Wang, Shih-Yu; Byambasuren, Oyunsanaa

    2015-07-01

    Recent incidences of mass livestock mortality, known as dzud, have called into question the sustainability of pastoral nomadic herding, the cornerstone of Mongolian culture. A total of 20 million head of livestock perished in the mortality events of 2000-2002, and 2009-2010. To mitigate the effects of such events on the lives of herders, international agencies such as the World Bank are taking increasing interest in developing tailored market-based solutions like index-insurance. Their ultimate success depends on understanding the historical context and underlying causes of mortality. In this paper we examine mortality in 21 Mongolian aimags (provinces) between 1955 and 2013 in order to explain its density independent cause(s) related to climate variability. We show that livestock mortality is most strongly linked to winter (November-February) temperatures, with incidences of mass mortality being most likely to occur because of an anomalously cold winter. Additionally, we find prior summer (July-September) drought and precipitation deficit to be important triggers for mortality that intensifies the effect of upcoming winter temperatures on livestock. Our density independent mortality model based on winter temperature, summer drought, summer precipitation, and summer potential evaporanspiration explains 48.4% of the total variability in the mortality dataset. The Mongolian index based livestock insurance program uses a threshold of 6% mortality to trigger payouts. We find that on average for Mongolia, the probability of exceedance of 6% mortality in any given year is 26% over the 59 year period between 1955 and 2013.

  8. Vulnerabilities and adaptive capacities of southwest rangeland livestock production to climate change

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The rangeland livestock industry across the southwestern US (California, Nevada, Arizona, Utah and New Mexico) consists of highly diverse production operations in these arid and semi-arid environments with low primary productivity. The vulnerabilities of this industry with projected increasing arid...

  9. Materials Data on Cr4H67C20(NO)16 (SG:1) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. Materials Data on KCa2P4H9O17 (SG:14) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-04-22

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  11. Materials Data on Si4H2O9 (SG:1) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  12. Materials Data on Si4H2O9 (SG:15) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  13. Materials Data on Si4H2O9 (SG:43) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  14. Materials Data on Li4H5Rh (SG:63) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on Th4H15 (SG:220) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-10

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Appreciating Your Great Lakes. A Guide for Developing Educational Projects. 4-H Marine Education Series - 2.

    ERIC Educational Resources Information Center

    Pennisi, Christine; Goettel, Robin, Ed.

    The Great Lakes are the largest series of fresh water bodies in the world. They are used for a wide variety of purposes by the 37 million citizens of the United States and Canada who live near the lakes and share this resource. This guide is intended to guide youth in acquiring training and field experience related to the Great Lakes in areas such…

  17. Materials Data on Na2B4H20O17 (SG:15) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  18. Materials Data on Cu4H3C2N5 (SG:186) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  19. Synthesis of 4H/fcc-Au@Metal Sulfide Core-Shell Nanoribbons.

    PubMed

    Fan, Zhanxi; Zhang, Xiao; Yang, Jian; Wu, Xue-Jun; Liu, Zhengdong; Huang, Wei; Zhang, Hua

    2015-09-02

    Although great advances on the synthesis of Au-semiconductor heteronanostructures have been achieved, the crystal structure of Au components is limited to the common face-centered cubic (fcc) phase. Herein, we report the synthesis of 4H/fcc-Au@Ag2S core-shell nanoribbon (NRB) heterostructures from the 4H/fcc Au@Ag NRBs via the sulfurization of Ag. Remarkably, the obtained 4H/fcc-Au@Ag2S NRBs can be further converted to a novel class of 4H/fcc-Au@metal sulfide core-shell NRB heterostructures, referred to as 4H/fcc-Au@MS (M = Cd, Pb or Zn), through the cation exchange. We believe that these novel 4H/fcc-Au@metal sulfide NRB heteronanostructures may show some promising applications in catalysis, surface enhanced Raman scattering, solar cells, photothermal therapy, etc.

  20. Seasonality constraints to livestock grazing intensity.

    PubMed

    Fetzel, Tamara; Havlik, Petr; Herrero, Mario; Erb, Karl-Heinz

    2017-04-01

    Increasing food production is essential to meet the future food demand of a growing world population. In light of pressing sustainability challenges such as climate change and the importance of the global livestock system for food security as well as GHG emissions, finding ways to increasing food production sustainably and without increasing competition for food crops is essential. Yet, many unknowns relate to livestock grazing, in particular grazing intensity, an essential variable to assess the sustainability of livestock systems. Here, we explore ecological limits to grazing intensity (GI; i.e. the fraction of net primary production consumed by grazing animals) by analysing the role of seasonality in natural grasslands. We estimate seasonal limitations to GI by combining monthly net primary production data and a map of global livestock distribution with assumptions on the length of nonfavourable periods that can be bridged by livestock (e.g. by browsing dead standing biomass, storage systems or biomass conservation). This allows us to derive a seasonality-limited potential GI, which we compare with the GI prevailing in 2000. We find that GI in 2000 lies below its potential on 39% of the total global natural grasslands, which has a potential for increasing biomass extraction of up to 181 MtC/yr. In contrast, on 61% of the area GI exceeds the potential, made possible by management. Mobilizing this potential could increase milk production by 5%, meat production by 4% or contribute to free up to 2.8 Mio km² of grassland area at the global scale if the numerous socio-ecological constraints can be overcome. We discuss socio-ecological trade-offs, which may reduce the estimated potential considerably and require the establishment of sound monitoring systems and an improved understanding of livestock system's role in the Earth system.

  1. 7 CFR 8.9 - Use in 4-H fund raising.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Food and Agriculture, United States Department of Agriculture, or a designee, if the fund-raising... 7 Agriculture 1 2014-01-01 2014-01-01 false Use in 4-H fund raising. 8.9 Section 8.9 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.9 Use in 4-H fund raising. (a)...

  2. 7 CFR 8.9 - Use in 4-H fund raising.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Food and Agriculture, United States Department of Agriculture, or a designee, if the fund-raising... 7 Agriculture 1 2012-01-01 2012-01-01 false Use in 4-H fund raising. 8.9 Section 8.9 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.9 Use in 4-H fund raising. (a)...

  3. 7 CFR 8.9 - Use in 4-H fund raising.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Food and Agriculture, United States Department of Agriculture, or a designee, if the fund-raising... 7 Agriculture 1 2013-01-01 2013-01-01 false Use in 4-H fund raising. 8.9 Section 8.9 Agriculture Office of the Secretary of Agriculture 4-H CLUB NAME AND EMBLEM § 8.9 Use in 4-H fund raising. (a)...

  4. 4-H PetPALS Juvenile Diversion Program Supports At-Risk Youth and Seniors

    ERIC Educational Resources Information Center

    Goble, Connie L.; Miller, Lucinda B.

    2014-01-01

    The 4-H PetPALS Juvenile Diversion Program provides a partnership opportunity with Extension and the juvenile court system to positively impact lives of at-risk youth. At-risk youth are taught by 4-H PetPALS adult volunteer leaders and 4-H PetPALS members to value and respect the human-animal bond, as well as to understand and empathize with…

  5. Energy potential from livestock and poultry wastes in the South. Agricultural Economic Report

    SciTech Connect

    Jones, H.B.; Ogden, E.A.

    1984-11-01

    Livestock and poultry wastes could produce significant amounts of biomass energy if conventional energy prices continue to rise. This study estimates the economically recoverable energy available through anaerobic digestion or direct burning of animal wastes in the South for the base year 1980 with projections for 1985 and 1990. Potential thermal energy from livestock and poultry wastes in 1990 could total more than 79.5 trillion Btu, or about 30 percent of the energy from such sources nationwide. The total potential farm value of biomass energy from livestock and poultry enterprises in the South could range from $344 million to $1.08 billion in 1990 depending upon the types of conventional energy displaced. Energy products from these wastes attained their highest value when substituted for LP gas.

  6. AB INITIO CHARACTERIZATION OF C{sup -}{sub 4}, C{sub 4}H, AND C{sub 4}H{sup -}

    SciTech Connect

    Senent, M. L.

    2010-01-10

    Using state-of-the-art theoretical methods, we investigate the stable isomers of C{sup -}{sub 4}, C{sub 4}H and C{sub 4}H{sup -}. Three of them are relevant for astrophysics and astrochemistry. These computations are performed using highly correlated ab initio methods and the aug-cc-pVXZ (X = T,Q) basis sets. In addition to the linear isomers, we predict the existence of several cyclic and branched forms for these molecules. For all the molecular species of interest here, sets of spectroscopic parameters are determined with perturbation theory, which compare quite well with experiment. For l - C{sub 4}H{sup -}(X {sup 1}SIGMA{sup +}), the quartic force field is computed at the coupled cluster level of theory. This force field is derived from full nine-dimensional potential energy surface generated close to the equilibrium geometry of this anion. Finally, we treat the thermochemistry of the hydrogen attachment and the electron attachment reactions that may lead to the formation of the C{sub 4}H{sup -} from either C{sup -}{sub 4} or C{sub 4}H.

  7. 7 CFR 760.304 - Covered livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., sheep, or swine; (2) Be livestock that would normally have been grazing the eligible grazing land or pastureland on the beginning date: (i) Of the qualifying drought during the normal grazing period for the specific type of grazing land or pastureland for the county or (ii) When the Federal agency prohibited...

  8. Biological control of livestock pests : Parasitoids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    House flies, Musca domestica L., and stable flies, Stomoxys calcitrans (L.), are common pests on livestock, poultry, and equine facilities. Biological control of filth flies with pupal parasitoids can be used in conjunction with other control methods as part of an integrated fly management program. ...

  9. 7 CFR 1416.203 - Eligible livestock.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... eligible county in accordance with 7 CFR 760.101, must meet all the following: (i) Be catfish or crawfish... meet all the following: (i) Be adult or non-adult dairy cattle, beef cattle, buffalo, beefalo, catfish... and any other Federal program for the same loss. Except catfish and crawfish, livestock that died...

  10. Baccharis Pteronioides Toxicity in Livestock and Hamsters.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since the early 1900’s, Baccharis pteronioides DC has been intermittently associated with livestock poisoning in the southwestern United States. In 2004, nearly 100 free ranging cows were reported poisoned by B. pteronioides in southern New Mexico. Initial field studies and post mortem examination...

  11. Is Continued Genetic Improvement of Livestock Sustainable?

    PubMed

    Hill, William G

    2016-03-01

    Large genetic improvements in the quantitative traits of growth, production, and efficiency of farmed livestock have been made over recent decades, and by introduction of genomic technology these are being enhanced. Such continued improvement requires that there be available variation to utilize. The evidence is that little variation has been lost and such rates are indeed sustainable in the future.

  12. Advanced Livestock Production: A Course of Study.

    ERIC Educational Resources Information Center

    Miller, Larry E.

    With the introduction of specialized courses of study in the third and fourth year of high school, it has become necessary to do more specialized work in the area of livestock production. The course is designed to provide a guideline to encourage intensified studies in this area, and outlines materials and methods, time allotment, and the use of…

  13. Monofluoroacetate-containing plants that are potentially toxic to livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many plants worldwide contain monofluoroacetate and cause sudden death in livestock. These plants are primarily found in the southern continents of Africa, Australia and South America where they negatively impact livestock production. This review highlights past and current research investigating: ...

  14. 7 CFR 205.239 - Livestock living conditions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.239 Livestock living conditions. (a) The producer of an organic livestock operation must establish and maintain...

  15. 7 CFR 205.239 - Livestock living conditions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.239 Livestock living conditions. (a) The producer of an organic livestock operation must establish and maintain...

  16. 7 CFR 205.239 - Livestock living conditions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.239 Livestock living conditions. (a) The producer of an organic livestock operation must establish and maintain...

  17. 7 CFR 205.239 - Livestock living conditions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.239 Livestock living conditions. (a) The producer of an organic livestock operation must establish and maintain...

  18. Livestock GRACEnet: A workgroup dedicated to evaluating and mitigating emissions from livestock production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ammonia, greenhouse gases, and other emissions (e.g., particulate matter, volatile organic compounds, hydrogen sulfide) from livestock production systems are being increasingly scrutinized by regulatory agencies. These pollutants, which are also generated by energy, industrial, and transportation se...

  19. 4-H and Forestry Afterschool Clubs: A Collaboration to Foster Stewardship Attitudes and Behaviors in Youth

    ERIC Educational Resources Information Center

    Gupta, Angela S.; Grant, Samantha; Strauss, Andrea Lorek

    2012-01-01

    The University of Minnesota Extension's 4-H and Forestry Afterschool program combined the 4-H structure and various forestry curricula to foster positive attitudes towards the environment and stewardship-related behaviors as these may serve as precursors to later choices that benefit the environment. Evaluation of third through fifth grade club…

  20. 4-H Youth Development: The Past, the Present, and the Future

    ERIC Educational Resources Information Center

    Borden, Lynne M.; Perkins, Daniel F.; Hawkey, Kyle

    2014-01-01

    The 4-H Program within Cooperative Extension is more than 100 years old. As we celebrate 100 years of Cooperative Extension, the foundation built by the 4-H Program serves as grounds to meet the needs of today's youth. The diversity of the youth who participate continues to grow, families continue to become less traditional, potential…

  1. Cinnamate 4-Hydroxylase (C4H) genes from Leucaena leucocephala: a pulp yielding leguminous tree.

    PubMed

    Kumar, Santosh; Omer, Sumita; Patel, Krunal; Khan, Bashir M

    2013-02-01

    Leucaena leucocephala is a leguminous tree species accounting for one-fourth of raw material supplied to paper and pulp industry in India. Cinnamate 4-Hydroxylase (C4H, EC 1.14.13.11) is the second gene of phenylpropanoid pathway and a member of cytochrome P450 family. There is currently intense interest to alter or modify lignin content of L. leucocephala. Three highly similar C4H alleles of LlC4H1 gene were isolated and characterized. The alleles shared more than 98 % sequence identity at amino acid level to each other. Binding of partial promoter of another C4H gene LlC4H2, to varying amounts of crude nuclear proteins isolated from leaf and stem tissues of L. leucocephala formed two loose and one strong complex, respectively, suggesting that the abundance of proteins that bind with the partial C4H promoter is higher in stem tissue than in leaf tissue. Quantitative Real Time PCR study suggested that among tissues of same age, root tissues had highest level of C4H transcripts. Maximum transcript level was observed in 30 day old root tissue. Among the tissues investigated, C4H activity was highest in 60 day old root tissues. Tissue specific quantitative comparison of lignin from developing seedling stage to 1 year old tree stage indicated that Klason lignin increased in tissues with age.

  2. Food Challenge: Serving Up 4-H to Non-Traditional Audiences

    ERIC Educational Resources Information Center

    Dodd, Sara; Follmer-Reece, Holly E.; Kostina-Ritchey, Erin; Reyna, Roxanna

    2015-01-01

    This article describes a novel approach for introducing 4-H to non-traditional/diverse audiences using 4-H Food Challenge. Set in a low SES and minority-serving rural school, Food Challenge was presented during the school day to all 7th grade students, with almost half voluntarily participating in an after-school club component. Program design…

  3. Characteristics and Perceptions of 4-H Participants: Gender and Age Differences across Adolescence

    ERIC Educational Resources Information Center

    Bartoszuk, Karin; Randall, Brandy A.

    2011-01-01

    The study reported here examined 367 adolescent 4-H participants in terms of demographic, psychological, behavioral, and relational characteristics, as well as their perceptions and experiences in 4-H. Overall, participants scored high on all outcome variables except having a diverse population in their club. Older participants were more…

  4. Birds in Your Backyard. 4-H Leaders Guide. L-5-17.

    ERIC Educational Resources Information Center

    Hawkes, Janet E.; Held Phillips, Diane

    This pocket folder of instructional materials is designed to introduce youth aged 9 to 12 to ornithology, the study of birds. The package includes a 4-H member's guide and a Leader's guide. The illustrated 4-H member's guide contains information about attracting and feeding birds. It also includes activities for cooking for birds, making bird…

  5. The Effects of Age, Gender, and 4-H Involvement on Life Skill Development

    ERIC Educational Resources Information Center

    Haas, Bruce E.; Mincemoyer, Claudia C.; Perkins, Daniel F.

    2015-01-01

    The study reported here examined the effects of age, gender, and 4-H involvement in clubs on life skill development of youth ages eight to 18 over a 12-month period. Regression analyses found age, gender, and 4-H involvement significantly influenced life skill development. Results found that females have higher levels of competencies in life…

  6. 4-H Healthy Living Programs with Impact: A National Environmental Scan

    ERIC Educational Resources Information Center

    Downey, Laura H.; Peterson, Donna J.; LeMenestrel, Suzanne; Leatherman, JoAnne; Lang, James

    2014-01-01

    The 4-H youth development program of the nation's 109 land-grant universities and the Cooperative Extension System is one of the largest youth development organization in the United States serving approximately six million youth. The 4-H Healthy Living initiative began in 2008 to promote achievement of optimal physical, social, and emotional…

  7. Acquisition, Custody, and Storage of Firearms Used in 4-H Shooting Sports Programs

    ERIC Educational Resources Information Center

    White, David J.; Smith, Jedediah D.

    2014-01-01

    Shooting sports has been a 4-H program offering since the 1930's. Tragic events related to the use of firearms as weapons have caused public and private entities to evaluate and consider the appropriateness of youth access to and usage of firearms. 4-H educators have the primary responsibility for managing the risk associated with shooting sports…

  8. An Examination of 4-H Youths' Needs and Interests, and Implications for State Conference.

    ERIC Educational Resources Information Center

    Rude, Tarri Lou

    A study was conducted to determine the needs and interests of teens in 4-H and whether the Washington State Conference is meeting those needs and interests. A mail survey was developed and sent to 557 teen 4-H members in Washington who were randomly selected from the 1985 state enrollment list. Three hundred and sixty questionnaires were returned…

  9. 7 CFR 8.9 - Use in 4-H fund raising.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...-raising programs using the 4-H Name or Emblem may be carried out for specific educational purposes. Such... Research, Education, and Extension Service, United States Department of Agriculture, or a designee, if the fund-raising program is multi-State or Nationwide. (b) When used to promote 4-H educational...

  10. Bringing Carnaval Drum and Dance Traditions into 4-H Programming for Latino Youth

    ERIC Educational Resources Information Center

    Conklin-Ginop, Evelyn; Braverman, Marc T.; Caruso, Robyn; Bone, Dennis

    2011-01-01

    4-H Bloco Drum and Dance is an afterschool program that teaches adolescents drumming, dancing, and theater arts in the rich traditions of Brazilian Carnaval. Teens learn to express themselves in a variety of modalities and perform at community events. The program was developed by a community coalition that included 4-H, other youth programs, and…

  11. Factors Related to the Developmental Experiences of Youth Serving as 4-H Camp Counselors

    ERIC Educational Resources Information Center

    Carter, David N.; Kotrlik, Joe W.

    2008-01-01

    The purpose of this study was to investigate the developmental experiences of high-school-aged 4-H youth volunteering as counselors at Louisiana 4-H summer camps. A total of 288 counselors from 10 different camping sessions participated in the study. The Youth Experiences Survey 2.0 and the Developmental Experience Survey measured the personal…

  12. Wolf depredation on livestock in Minnesota

    USGS Publications Warehouse

    Fritts, S.H.

    1982-01-01

    Depredation by wolves (Canis lupus) on cattle, sheep, and other livestock in Minnesota currently is a minor problem except to a few individual farmers. Indices to the seriousness of the problem are available only from recent years, so historical trends cannot be detected. From 1976 through 1980 the number of farms in the wolf range suffering verified losses to wolves ranged from 9 to 19 (mean of x = 13) per year out of about 12,230. From 1977 through 1980, the highest cattle losses claimed by farmers were 0.45 per 1,000 cattle available in 1979; the highest sheep losses claimed were 1.18 per 1,000 available in 1980. Many claims of losses (especially of calves) are based on missing animals, and few wolves are involved in the verified losses. Most losses occur in summer when livestock are released to graze in open and wooded pasture. Herd management practices, such as calving in forested or brushy pastures and disposal of carcasses in or near pastures, are responsible for many instances of wolf depredation. Failure to distinguish wolves from coyotes (Canis latrans) has contributed to an exaggerated view of the importance of wolves as livestock predators. Recently the number of wolves killed in depredation control has declined, whereas the number of livestock killed has remained fairly stable. Results of the U.S. Fish and Wildlife Service's depredation- control program in 1979 and 1980 suggest that highly restricted trapping, coupled with other management methods, has potential for reducing both livestock losses and the number of wolves that need to be killed.

  13. Livestock and feed water productivity in the mixed crop-livestock system.

    PubMed

    Bekele, M; Mengistu, A; Tamir, B

    2017-02-22

    Recently with limited information from intensified grain-based farming systems in developed countries, livestock production is challenged as being huge consumer of freshwater. The smallholder mixed crop-livestock (MCL) system which is predominant in developing countries like Ethiopia, is maintained with considerable contributions of crop residues (CR) to livestock feeding. Inclusion of CR is expected to reduce the water requirement for feed production resulting improvement in livestock water productivity (LWP). This study was conducted to determine feed water productivity (FWP) and LWP in the MCL system. A multistage sampling procedure was followed to select farmers from different wealth status. Wealth status dictated by ownership of key farm resources such as size of cropland and livestock influenced the magnitude of livestock outputs, FWP and LWP. Significant difference in feed collected, freshwater evapotranspired, livestock outputs and water productivity (WP) were observed between wealth groups, where wealthier are relatively more advantaged. Water productivity of CR and grazing land (GL) analyzed separately showed contrasting differences where better-off gained more on CR, whereas vice versa on GL. These counterbalancing of variations may justify the non-significant difference in total FWP between wealth groups. Despite observed differences, low WP on GL indicates the need of interventions at all levels. The variation in WP of CR is attributed to availability of production factors which restrained the capacity of poor farmers most. A linear relationship between the proportion of CR in livestock feed and FWP was evident, but the relationship with LWP was not likely linear. As CR are inherently low in digestibility and nutritive values which have an effect on feed conversion into valuable livestock products and services, increasing share of CR beyond an optimum level is not a viable option to bring improvements in livestock productivity as expressed in terms of

  14. Unusual reaction paths of SN2 nucleophile substitution reactions CH4 + H- → CH4 + H- and CH4 + F- → CH3F + H-: Quantum chemical calculations

    NASA Astrophysics Data System (ADS)

    Minyaev, Ruslan M.; Quapp, Wolfgang; Schmidt, Benjamin; Getmanskii, Ilya V.; Koval, Vitaliy V.

    2013-11-01

    Quantum chemical (CCSD(full)/6-311++G(3df,3pd), CCSD(T)(full)/6-311++G(3df,3pd)) and density function theory (B3LYP/6-311++G(3df,3pd)) calculations were performed for the SN2 nucleophile substitution reactions CH4 + H- → CH4 + H- and CH4 + F- → CH3F + H-. The calculated gradient reaction pathways for both reactions have an unusual behavior. An unusual stationary point of index 2 lies on the gradient reaction path. Using Newton trajectories for the reaction path, we can detect VRI point at which the reaction path branches.

  15. Volumetric Properties of the Mixture Oxolan-2-one C4H6O2 + C4H10O Butan-1-ol (VMSD1511, LB4906_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Oxolan-2-one C4H6O2 + C4H10O Butan-1-ol (VMSD1511, LB4906_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  16. Structural analysis of the 3C|4H boundaries formed on prismatic planes in 4H-SiC epitaxial films

    NASA Astrophysics Data System (ADS)

    Yamashita, T.; Matsuhata, H.; Naijo, T.; Momose, K.; Osawa, H.

    2016-12-01

    The boundaries between 3C and 4H-SiC domains on the prismatic planes of hexagonal lattices formed in a 4H-SiC epitaxial film were investigated using both transmission and scanning transmission electron microscopy. These observations determined that the boundaries have a periodic structure, in which each unit cell consists of 12 basal planes of the hexagonal lattice. Six Shockley partial dislocations are situated in each unit cell of the boundary structure. Burgers vectors and core structures of these partial dislocations are discussed.

  17. Genotype by environment interaction and breeding for robustness in livestock

    PubMed Central

    Rauw, Wendy M.; Gomez-Raya, Luis

    2015-01-01

    The increasing size of the human population is projected to result in an increase in meat consumption. However, at the same time, the dominant position of meat as the center of meals is on the decline. Modern objections to the consumption of meat include public concerns with animal welfare in livestock production systems. Animal breeding practices have become part of the debate since it became recognized that animals in a population that have been selected for high production efficiency are more at risk for behavioral, physiological and immunological problems. As a solution, animal breeding practices need to include selection for robustness traits, which can be implemented through the use of reaction norms analysis, or though the direct inclusion of robustness traits in the breeding objective and in the selection index. This review gives an overview of genotype × environment interactions (the influence of the environment, reaction norms, phenotypic plasticity, canalization, and genetic homeostasis), reaction norms analysis in livestock production, options for selection for increased levels of production and against environmental sensitivity, and direct inclusion of robustness traits in the selection index. Ethical considerations of breeding for improved animal welfare are discussed. The discussion on animal breeding practices has been initiated and is very alive today. This positive trend is part of the sustainable food production movement that aims at feeding 9.15 billion people not just in the near future but also beyond. PMID:26539207

  18. 43 CFR 4710.5 - Closure to livestock grazing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Closure to livestock grazing. 4710.5... FREE-ROAMING HORSES AND BURROS Management Considerations § 4710.5 Closure to livestock grazing. (a) If... grazing use by all or a particular kind of livestock. (b) All public lands inhabited by wild horses...

  19. 29 CFR 780.327 - Production of livestock.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Production of livestock. 780.327 Section 780.327 Labor...) Statutory Provisions § 780.327 Production of livestock. For an employee to be engaged in the production of... inspecting and repairing fences, wells, and windmills would be considered as the production of livestock....

  20. 9 CFR 313.1 - Livestock pens, driveways and ramps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Livestock pens, driveways and ramps. 313.1 Section 313.1 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.1 Livestock pens, driveways and ramps....

  1. 9 CFR 313.1 - Livestock pens, driveways and ramps.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Livestock pens, driveways and ramps. 313.1 Section 313.1 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.1 Livestock pens, driveways and ramps....

  2. 9 CFR 313.1 - Livestock pens, driveways and ramps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Livestock pens, driveways and ramps. 313.1 Section 313.1 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.1 Livestock pens, driveways and ramps....

  3. 76 FR 62313 - Traceability for Livestock Moving Interstate

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-07

    ... Livestock Moving Interstate AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Proposed rule... livestock moving interstate. This action will allow interested persons additional time to prepare and submit... requirements for the traceability of livestock moving interstate. Comments on the proposed rule were...

  4. 9 CFR 309.13 - Disposition of condemned livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Disposition of condemned livestock... INSPECTION AND CERTIFICATION ANTE-MORTEM INSPECTION § 309.13 Disposition of condemned livestock. (a) Except as otherwise provided in this part, livestock identified as U.S. Condemned shall be killed by...

  5. 7 CFR 53.15 - Accessibility to livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Accessibility to livestock. 53.15 Section 53.15... AGRICULTURAL MARKETING ACT OF 1946 AND THE EGG PRODUCTS INSPECTION ACT (CONTINUED) LIVESTOCK (GRADING, CERTIFICATION, AND STANDARDS) Regulations Service § 53.15 Accessibility to livestock. (a) The applicant...

  6. 25 CFR 167.14 - Movement of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Movement of livestock. 167.14 Section 167.14 Indians... Movement of livestock. Annually, prior to the normal lamb buying season, the Central Grazing Committee... and the procedures and methods to be used in moving livestock to market. All movements of...

  7. 9 CFR 71.20 - Approval of livestock facilities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... livestock that are known to be infected, exposed, high-risk and scrapie-positive or suspect, or that show... reactor, suspect, exposed, high-risk, or scrapie positive livestock shall be held in quarantined pens apart from all other livestock at the facility. This requirement shall not apply to...

  8. The Effect of Poisonous Range Plants on Abortions in Livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Natural toxins from plants and fungi, in addition to man-made toxicants, have been implicated with abortion, embryonic death, or neonatal loss in livestock. Plants causing reproductive problems for livestock can be found on most, if not all rangelands worldwide, thus exposing livestock at various t...

  9. 9 CFR 309.17 - Livestock used for research.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Livestock used for research. 309.17... INSPECTION AND CERTIFICATION ANTE-MORTEM INSPECTION § 309.17 Livestock used for research. (a) No livestock used in any research investigation involving an experimental biological product, drug, or...

  10. 9 CFR 309.17 - Livestock used for research.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Livestock used for research. 309.17... INSPECTION AND CERTIFICATION ANTE-MORTEM INSPECTION § 309.17 Livestock used for research. (a) No livestock used in any research investigation involving an experimental biological product, drug, or...

  11. Sustainable livestock production on rangelands: Emerging trends in the USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A recent review of statistics published by the United Nations Food and Agriculture Organization showed that global livestock numbers have increased steadily over the past 30 years. By 2030, livestock numbers in the developing world are expected to reach record highs that will surpass livestock popu...

  12. Ultra high voltage MOS controlled 4H-SiC power switching devices

    NASA Astrophysics Data System (ADS)

    Ryu, S.; Capell, C.; Van Brunt, E.; Jonas, C.; O'Loughlin, M.; Clayton, J.; Lam, K.; Pala, V.; Hull, B.; Lemma, Y.; Lichtenwalner, D.; Zhang, Q. J.; Richmond, J.; Butler, P.; Grider, D.; Casady, J.; Allen, S.; Palmour, J.; Hinojosa, M.; Tipton, C. W.; Scozzie, C.

    2015-08-01

    Ultra high voltage (UHV, >15 kV) 4H-silicon carbide (SiC) power devices have the potential to significantly improve the system performance, reliability, and cost of energy conversion systems by providing reduced part count, simplified circuit topology, and reduced switching losses. In this paper, we compare the two MOS based UHV 4H-SiC power switching devices; 15 kV 4H-SiC MOSFETs and 15 kV 4H-SiC n-IGBTs. The 15 kV 4H-SiC MOSFET shows a specific on-resistance of 204 mΩ cm2 at 25 °C, which increased to 570 mΩ cm2 at 150 °C. The 15 kV 4H-SiC MOSFET provides low, temperature-independent, switching losses which makes the device more attractive for applications that require higher switching frequencies. The 15 kV 4H-SiC n-IGBT shows a significantly lower forward voltage drop (VF), along with reasonable switching performance, which make it a very attractive device for high voltage applications with lower switching frequency requirements. An electrothermal analysis showed that the 15 kV 4H-SiC n-IGBT outperforms the 15 kV 4H-SiC MOSFET for applications with switching frequencies of less than 5 kHz. It was also shown that the use of a carrier storage layer (CSL) can significantly improve the conduction performance of the 15 kV 4H-SiC n-IGBTs.

  13. HIF-P4H-2 deficiency protects against skeletal muscle ischemia-reperfusion injury.

    PubMed

    Karsikas, Sara; Myllymäki, Mikko; Heikkilä, Minna; Sormunen, Raija; Kivirikko, Kari I; Myllyharju, Johanna; Serpi, Raisa; Koivunen, Peppi

    2016-03-01

    We show here that mice hypomorphic for hypoxia-inducible factor prolyl 4-hydroxylase-2 (HIF-P4H-2) (Hif-p4h-2 (gt/gt)), the main regulator of the stability of the HIFα subunits, have normoxic stabilization of HIF-1α and HIF-2α in their skeletal muscles. The size of the capillaries, but not their number, was increased in the skeletal muscles of the Hif-p4h-2 (gt/gt) mice, whereas the amount of glycogen was reduced. The expression levels of genes for glycolytic enzymes, glycogen branching enzyme 1 and monocarboxylate transporter 4, were increased in the Hif-p4h-2 (gt/gt) skeletal muscles, whereas no significant increases were detected in the levels of any vasculature-influencing factor studied. Serum lactate levels of the Hif-p4h-2 (gt/gt) mice recovered faster than those of the wild type following exercise. The Hif-p4h-2 (gt/gt) mice had elevated hepatic phosphoenolpyruvate carboxykinase activity, which may have contributed to the faster clearance of lactate. The Hif-p4h-2 (gt/gt) mice had smaller infarct size following limb ischemia-reperfusion injury. The increased capillary size correlated with the reduced infarct size. Following ischemia-reperfusion, glycogen content and ATP/ADP and CrP/Cr levels of the skeletal muscle of the Hif-p4h-2 (gt/gt) mice were higher than in the wild type. The higher glycogen content correlated with increased expression of phosphofructokinase messenger RNA (mRNA) and the increased ATP/ADP and CrP/Cr levels with reduced apoptosis, suggesting that HIF-P4H-2 deficiency supported energy metabolism during ischemia-reperfusion and protection against injury. Key messages: HIF-P4H-2 deficiency protects skeletal muscle from ischemia-reperfusion injury. The mechanisms involved are mediated via normoxic HIF-1α and HIF-2α stabilization. HIF-P4H-2 deficiency increases capillary size but not number. HIF-P4H-2 deficiency maintains energy metabolism during ischemia-reperfusion.

  14. Application of Prebiotics and Probiotics in Livestock

    NASA Astrophysics Data System (ADS)

    Collins, James W.; La Ragione, Roberto M.; Woodward, Martin J.; Searle, Laura E. J.

    The advent of antibiotics and their use for treatment of clinical manifestations of infections has had a profound impact on animal health and welfare. In addition to direct application in the control of infection, low concentrations of antibiotics given in animal feed has been shown to correlate with higher health status and improved performance in terms of feed conversion (productive weight gain). Thus it is that antibiotics have been used as “growth promoters” in feed for livestock since the 1940s (Cromwell, 2001). Since the inception of this growth promotion concept there has been a debate on precisely how low level antibiotics mediate their action and whether or not this contributes to the acquisition of resistance in the bacterial flora of livestock.

  15. Livestock and microbiological risk (a review).

    PubMed

    Zicari, Giuseppe; Soardo, Vincenzo; Rivetti, Daniela; Cerrato, Elena; Russo, Domenico

    2013-01-01

    The presence of pathogens in animal manure depends on several factors such as, for example, the species, age, type of power supply, state of health, methods and times of storage, treatments administered. Currently there are no specific requirements for the minimum sanitary standards of livestock manure to be used in agriculture, or even of the digestate resulting from anaerobic digestion, such as cattle slurry and plant matrices (e.g. maize). While there are some indications for products fermented aerobically (compost deriving also from manure) and the sludge resulting from wastewater treatment and intended for use as fertilizers. In this paper we sum up the information given in the scientific literature on the viability of some microorganisms and on the effects of the anaerobic digestion of livestock manure and plant matter, such as maize, on the microbial concentrations.

  16. Livestock in a changing climate: production system transitions as an adaptation strategy for agriculture

    NASA Astrophysics Data System (ADS)

    Weindl, Isabelle; Lotze-Campen, Hermann; Popp, Alexander; Müller, Christoph; Havlík, Petr; Herrero, Mario; Schmitz, Christoph; Rolinski, Susanne

    2015-09-01

    Livestock farming is the world’s largest land use sector and utilizes around 60% of the global biomass harvest. Over the coming decades, climate change will affect the natural resource base of livestock production, especially the productivity of rangeland and feed crops. Based on a comprehensive impact modeling chain, we assess implications of different climate projections for agricultural production costs and land use change and explore the effectiveness of livestock system transitions as an adaptation strategy. Simulated climate impacts on crop yields and rangeland productivity generate adaptation costs amounting to 3% of total agricultural production costs in 2045 (i.e. 145 billion US). Shifts in livestock production towards mixed crop-livestock systems represent a resource- and cost-efficient adaptation option, reducing agricultural adaptation costs to 0.3% of total production costs and simultaneously abating deforestation by about 76 million ha globally. The relatively positive climate impacts on grass yields compared with crop yields favor grazing systems inter alia in South Asia and North America. Incomplete transitions in production systems already have a strong adaptive and cost reducing effect: a 50% shift to mixed systems lowers agricultural adaptation costs to 0.8%. General responses of production costs to system transitions are robust across different global climate and crop models as well as regarding assumptions on CO2 fertilization, but simulated values show a large variation. In the face of these uncertainties, public policy support for transforming livestock production systems provides an important lever to improve agricultural resource management and lower adaptation costs, possibly even contributing to emission reduction.

  17. Grazing livestock are exposed to terrestrial cyanobacteria.

    PubMed

    McGorum, Bruce C; Pirie, R Scott; Glendinning, Laura; McLachlan, Gerry; Metcalf, James S; Banack, Sandra A; Cox, Paul A; Codd, Geoffrey A

    2015-02-25

    While toxins from aquatic cyanobacteria are a well-recognised cause of disease in birds and animals, exposure of grazing livestock to terrestrial cyanobacteria has not been described. This study identified terrestrial cyanobacteria, predominantly Phormidium spp., in the biofilm of plants from most livestock fields investigated. Lower numbers of other cyanobacteria, microalgae and fungi were present on many plants. Cyanobacterial 16S rDNA, predominantly from Phormidium spp., was detected in all samples tested, including 6 plant washings, 1 soil sample and ileal contents from 2 grazing horses. Further work was performed to test the hypothesis that ingestion of cyanotoxins contributes to the pathogenesis of some currently unexplained diseases of grazing horses, including equine grass sickness (EGS), equine motor neuron disease (EMND) and hepatopathy. Phormidium population density was significantly higher on EGS fields than on control fields. The cyanobacterial neurotoxic amino acid 2,4-diaminobutyric acid (DAB) was detected in plant washings from EGS fields, but worst case scenario estimations suggested the dose would be insufficient to cause disease. Neither DAB nor the cyanobacterial neurotoxins β-N-methylamino-L-alanine and N-(2-aminoethyl) glycine were detected in neural tissue from 6 EGS horses, 2 EMND horses and 7 control horses. Phormidium was present in low numbers on plants where horses had unexplained hepatopathy. This study did not yield evidence linking known cyanotoxins with disease in grazing horses. However, further study is warranted to identify and quantify toxins produced by cyanobacteria on livestock fields, and determine whether, under appropriate conditions, known or unknown cyanotoxins contribute to currently unexplained diseases in grazing livestock.

  18. Domestic livestock resources of Turkey: water buffalo.

    PubMed

    Yilmaz, Orhan; Ertugrul, Mehmet; Wilson, Richard Trevor

    2012-04-01

    Water buffalo are an ancient component of Turkey's domestic livestock resources. Commonly referred to as the Anatolian buffalo the animal is part of the Mediterranean group which includes Syrian, Egyptian and Southeast European animals. Once quite numerous, there have been drastic reductions in their numbers since the 1970s due to intensification of dairy activities, agricultural mechanization and changing consumer preferences. The main areas of distribution are in northwest Turkey in the Marmara and Black Sea Regions. Buffalo are kept in small herds by livestock and mixed crop-livestock farmers. Milk is the main product, meat is largely a by-product of the dairy function and provision of the once-important draught power is now a minor output. Buffalo milk is used to prepare a variety of speciality products but output of both milk and meat is very low in comparison to cattle. Conditions of welfare and health status are not optimal. Internal parasites are a constraint on productivity. Some buffalo are being used for conservation grazing in the Black Sea area to maintain optimal conditions for bird life in a nature reserve. Long neglected by government there are recent activities to establish conservation herds, set up in vitro banks and undertake molecular characterization. More effort is needed by government to promote buffalo production and to engage the general public in conservation of their national heritage.

  19. Identification of selection signatures in livestock species.

    PubMed

    de Simoni Gouveia, João José; da Silva, Marcos Vinicius Gualberto Barbosa; Paiva, Samuel Rezende; de Oliveira, Sônia Maria Pinheiro

    2014-06-01

    The identification of regions that have undergone selection is one of the principal goals of theoretical and applied evolutionary genetics. Such studies can also provide information about the evolutionary processes involved in shaping genomes, as well as physical and functional information about genes/genomic regions. Domestication followed by breed formation and selection schemes has allowed the formation of very diverse livestock breeds adapted to a wide variety of environments and with special characteristics. The advances in genomics in the last five years have enabled the development of several methods to detect selection signatures and have resulted in the publication of a considerable number of studies involving livestock species. The aims of this review are to describe the principal effects of natural/artificial selection on livestock genomes, to present the main methods used to detect selection signatures and to discuss some recent results in this area. This review should be useful also to research scientists working with wild animals/non-domesticated species and plant biologists working with breeding and evolutionary biology.

  20. Identification of selection signatures in livestock species

    PubMed Central

    de Simoni Gouveia, João José; da Silva, Marcos Vinicius Gualberto Barbosa; Paiva, Samuel Rezende; de Oliveira, Sônia Maria Pinheiro

    2014-01-01

    The identification of regions that have undergone selection is one of the principal goals of theoretical and applied evolutionary genetics. Such studies can also provide information about the evolutionary processes involved in shaping genomes, as well as physical and functional information about genes/genomic regions. Domestication followed by breed formation and selection schemes has allowed the formation of very diverse livestock breeds adapted to a wide variety of environments and with special characteristics. The advances in genomics in the last five years have enabled the development of several methods to detect selection signatures and have resulted in the publication of a considerable number of studies involving livestock species. The aims of this review are to describe the principal effects of natural/artificial selection on livestock genomes, to present the main methods used to detect selection signatures and to discuss some recent results in this area. This review should be useful also to research scientists working with wild animals/non-domesticated species and plant biologists working with breeding and evolutionary biology. PMID:25071397

  1. Livestock waste-to-bioenergy generation opportunities.

    PubMed

    Cantrell, Keri B; Ducey, Thomas; Ro, Kyoung S; Hunt, Patrick G

    2008-11-01

    The use of biological and thermochemical conversion (TCC) technologies in livestock waste-to-bioenergy treatments can provide livestock operators with multiple value-added, renewable energy products. These products can meet heating and power needs or serve as transportation fuels. The primary objective of this work is to present established and emerging energy conversion opportunities that can transform the treatment of livestock waste from a liability to a profit center. While biological production of methanol and hydrogen are in early research stages, anaerobic digestion is an established method of generating between 0.1 to 1.3m3m(-3)d(-1) of methane-rich biogas. The TCC processes of pyrolysis, direct liquefaction, and gasification can convert waste into gaseous fuels, combustible oils, and charcoal. Integration of biological and thermal-based conversion technologies in a farm-scale hybrid design by combining an algal CO2-fixation treatment requiring less than 27,000m2 of treatment area with the energy recovery component of wet gasification can drastically reduce CO2 emissions and efficiently recycle nutrients. These designs have the potential to make future large scale confined animal feeding operations sustainable and environmentally benign while generating on-farm renewable energy.

  2. Reducing uncertainty in nitrogen budgets for African livestock systems

    NASA Astrophysics Data System (ADS)

    Rufino, M. C.; Brandt, P.; Herrero, M.; Butterbach-Bahl, K.

    2014-10-01

    Livestock is poorly represented in N budgets for the African continent although some studies have examined livestock-related N flows at different levels. Livestock plays an important role in N cycling and therefore on N budgets including livestock-related flows. This study reviews the literature on N budgets for Africa to identify factors contributing to uncertainties. Livestock densities are usually modelled because of the lack of observational spatial data. Even though feed availability and quality varies across seasons, most studies use constant livestock excretion rates, and excreta are usually assumed to be uniformly distributed onto the land. Major uncertainties originate in the fraction of manure managed, and emission factors which may not reflect the situation of Africa. N budgets use coarse assumptions on production, availability, and use of crop residues as livestock feed. No flows between croplands-livestock and rangelands reflect the lack of data. Joint efforts are needed for spatial data collection of livestock data, crowdsourcing appears to be a promising option. The focus of the assessment of N budgets must go beyond croplands to include livestock and crop-livestock flows. We propose a nested systems definition of livestock systems to link local, regional level, and continental level and to increase the usefulness of point measurements of N losses. Scientists working at all levels should generate data to calibrate process-based models. Measurements in the field should not only concentrate on greenhouse gas emissions, but need to include crop and livestock production measurements, soil stock changes and other N loss pathways such as leaching, run-off and volatilization to assess management practices and trade-offs. Compared to the research done in other continents on N flows in livestock systems, there are few data for Africa, and therefore concerted effort will be needed to generate sufficient data for modelling.

  3. Epigenetic marks: regulators of livestock phenotypes and conceivable sources of missing variation in livestock improvement programs.

    PubMed

    Ibeagha-Awemu, Eveline M; Zhao, Xin

    2015-01-01

    Improvement in animal productivity has been achieved over the years through careful breeding and selection programs. Today, variations in the genome are gaining increasing importance in livestock improvement strategies. Genomic information alone, however, explains only a part of the phenotypic variance in traits. It is likely that a portion of the unaccounted variance is embedded in the epigenome. The epigenome encompasses epigenetic marks such as DNA methylation, histone tail modifications, chromatin remodeling, and other molecules that can transmit epigenetic information such as non-coding RNA species. Epigenetic factors respond to external or internal environmental cues such as nutrition, pathogens, and climate, and have the ability to change gene expression leading to emergence of specific phenotypes. Accumulating evidence shows that epigenetic marks influence gene expression and phenotypic outcome in livestock species. This review examines available evidence of the influence of epigenetic marks on livestock (cattle, sheep, goat, and pig) traits and discusses the potential for consideration of epigenetic markers in livestock improvement programs. However, epigenetic research activities on farm animal species are currently limited partly due to lack of recognition, funding and a global network of researchers. Therefore, considerable less attention has been given to epigenetic research in livestock species in comparison to extensive work in humans and model organisms. Elucidating therefore the epigenetic determinants of animal diseases and complex traits may represent one of the principal challenges to use epigenetic markers for further improvement of animal productivity.

  4. Livestock GRACEnet: A Workgroup Dedicated to Evaluating and Mitigating Emissions from Livestock Production.

    PubMed

    Leytem, April B; Dungan, Robert S

    2014-07-01

    Ammonia, greenhouse gases, and particulate emissions from livestock operations can potentially affect air quality at local, regional, and even global scales. These pollutants, many of which are generated through various anthropogenic activities, are being increasingly scrutinized by regulatory authorities. Regulation of emissions from livestock production systems will ultimately increase on farm costs, which will then be passed onto consumers. Therefore, it is essential that scientifically based emission factors are developed for on-farm emissions of air quality constituents to improve inventories and assign appropriate reduction targets. To generate a larger database of on-farm emissions, the USDA-ARS created the workgroup Livestock GRACEnet (Greenhouse gas Reduction through Agricultural Carbon Enhancement Network). This introduction for the special section of papers highlights some of the research presently being conducted by members of Livestock GRACEnet with the intent of drawing attention to critical information gaps, such as (i) improving emissions measurements; (ii) developing emissions factors; (iii) developing and validating tools for estimating emissions; and (iv) mitigating emissions. We also provide a synthesis of the literature with respect to key research areas related to livestock emissions, including feeding strategies, animal housing, manure management, and manure land application, and discuss future research priorities and directions.

  5. Epigenetic marks: regulators of livestock phenotypes and conceivable sources of missing variation in livestock improvement programs

    PubMed Central

    Ibeagha-Awemu, Eveline M.; Zhao, Xin

    2015-01-01

    Improvement in animal productivity has been achieved over the years through careful breeding and selection programs. Today, variations in the genome are gaining increasing importance in livestock improvement strategies. Genomic information alone, however, explains only a part of the phenotypic variance in traits. It is likely that a portion of the unaccounted variance is embedded in the epigenome. The epigenome encompasses epigenetic marks such as DNA methylation, histone tail modifications, chromatin remodeling, and other molecules that can transmit epigenetic information such as non-coding RNA species. Epigenetic factors respond to external or internal environmental cues such as nutrition, pathogens, and climate, and have the ability to change gene expression leading to emergence of specific phenotypes. Accumulating evidence shows that epigenetic marks influence gene expression and phenotypic outcome in livestock species. This review examines available evidence of the influence of epigenetic marks on livestock (cattle, sheep, goat, and pig) traits and discusses the potential for consideration of epigenetic markers in livestock improvement programs. However, epigenetic research activities on farm animal species are currently limited partly due to lack of recognition, funding and a global network of researchers. Therefore, considerable less attention has been given to epigenetic research in livestock species in comparison to extensive work in humans and model organisms. Elucidating therefore the epigenetic determinants of animal diseases and complex traits may represent one of the principal challenges to use epigenetic markers for further improvement of animal productivity. PMID:26442116

  6. Al4H7(-) is a resilient building block for aluminum hydrogen cluster materials.

    PubMed

    Roach, P J; Reber, A C; Woodward, W H; Khanna, S N; Castleman, A W

    2007-09-11

    The formation and oxygen etching of Al(n)H(m)(-) clusters are characterized in a flow reactor experiment with first-principles theoretical investigations to demonstrate the exceptional stability of Al(4)H(7)(-). The origin of the preponderance of Al(4)H(7)(-) in the mass spectra of hydrogenated aluminum anions and its resistance to O(2) etching are discussed. Al(4)H(7)(-) is shown to have the ability to bond with ionic partners to form stable hydrides through addition of an alkali atom [XAl(4)H(7) (X = Li-Cs)]. An intuitive model that can predict the existence of stable hydrogenated cluster species is proposed. The potential synthetic utility of the superatom assemblies built on these units is addressed.

  7. Prismatic Slip in PVT-Grown 4H-SiC Crystals

    NASA Astrophysics Data System (ADS)

    Guo, Jianqiu; Yang, Yu; Raghothamachar, Balaji; Kim, Jungyu; Dudley, Michael; Chung, Gilyong; Sanchez, Edward; Quast, Jeffrey; Manning, Ian

    2017-04-01

    Basal plane slip is the most frequently observed deformation mechanism in 4H-type silicon carbon (4H-SiC) single crystals grown by the physical vapor transport (PVT) method. However, it was recently reported that dislocations in such crystals can also glide in prismatic slip systems. In this study, we observed nonuniform distributions of three sets of prismatic dislocations in a commercial 4H-SiC substrate wafer. The nonuniformity is a result of the distribution of resolved shear stress on each prismatic slip system caused by radial thermal gradients in the growing crystal boule. A radial thermal model has been developed to estimate the thermal stress across the entire area of the crystal boule during PVT growth. The model results show excellent agreement with the observations, confirming that radial thermal gradients play a key role in activating prismatic slip in 4H-SiC during bulk growth.

  8. Prismatic Slip in PVT-Grown 4H-SiC Crystals

    NASA Astrophysics Data System (ADS)

    Guo, Jianqiu; Yang, Yu; Raghothamachar, Balaji; Kim, Jungyu; Dudley, Michael; Chung, Gilyong; Sanchez, Edward; Quast, Jeffrey; Manning, Ian

    2016-11-01

    Basal plane slip is the most frequently observed deformation mechanism in 4H-type silicon carbon (4H-SiC) single crystals grown by the physical vapor transport (PVT) method. However, it was recently reported that dislocations in such crystals can also glide in prismatic slip systems. In this study, we observed nonuniform distributions of three sets of prismatic dislocations in a commercial 4H-SiC substrate wafer. The nonuniformity is a result of the distribution of resolved shear stress on each prismatic slip system caused by radial thermal gradients in the growing crystal boule. A radial thermal model has been developed to estimate the thermal stress across the entire area of the crystal boule during PVT growth. The model results show excellent agreement with the observations, confirming that radial thermal gradients play a key role in activating prismatic slip in 4H-SiC during bulk growth.

  9. Quantum chemical study of ternary mixtures of: HNO3:H2SO4:H2O

    NASA Astrophysics Data System (ADS)

    Verdes, M. A.; Gómez, P. C.; Gálvez, O.

    2009-04-01

    Water, nitric acid and sulfuric acid are important atmospheric species as individual species and as hydrogen-bonded aggregates involved in many physical-chemical processes both superficial and bulk. The importance of heterogeneous chemical reactions taking place on ice surfaces, either solid water or solid water plus nitric or sulfuric acid, is well established now in relation to the ozone-depleting mechanisms. Also the importance of liquid droplets formed by HNO3.H2SO4.H2O as components of PSC was soon recognized [1-3]. Finally the physical properties of finely divided aqueous systems is an interesting and active field of research in which theoretical information on the microphysical domain systems may help to understand and rationalize the wealth of experimental information. This can also be the initial step in the study of more complex mixtures with higher amounts of water or variable proportions of their constituents. This kind of calculations have been successfully performed in the past[4]. We present here our results on the structure and spectroscopic and thermodynamic properties of the energy-lowest lying structures among those thermodynamically stable formed by linking the acids plus water. The calculations have been carried out by means of DFT methods (in particular the successful B3LYP) using different basis sets that contain appropriate sets of polarization and diffuse functions up to quadruple-Z quality (Dunninǵs aug-cc-pVQZ). Careful assessment of the dependability of the methodology used has been carried out. This work has been supported by the Spanish Ministry of Education, Projects FIS2007-61686 and CTQ2008-02578/BQU References: [1] Carslaw, K. S. et al.: Geophys. Res. Lett. 21, 2479-2482, 1994 [2] Drdla, K. Et al. :Geophys. Res. Lett. 21, 2473-2478, 1994 [3] Tabazadeh, A. et al.: Geophys. Res. Lett 21, 1619-1622, 1994 [4] Escribano, R et al.: J. J. Chem. Phys A 2003, 107, 652.

  10. Enantioselective one-pot synthesis of 2-amino-4-(indol-3-yl)-4H-chromenes.

    PubMed

    Chen, Weiliang; Cai, Yunfei; Fu, Xuan; Liu, Xiaohua; Lin, Lili; Feng, Xiaoming

    2011-09-16

    An enantioselective one-pot synthesis of 2-amino-4-(indol-3-yl)-4H-chromenes via a Knoevenagel/Pinner/Friedel-Crafts reaction of salicylaldehyde, malononitrile, and indole is presented. Moderate to good yields (up to 89%) and high enantioselectivities (up to 90% ee) were obtained with an N,N'-dioxide-Zn(II) complex as the catalyst. This strategy provides an efficient and convenient method to access enantiomerically enriched 2-amino-4H-chromene derivatives.

  11. Phosphorus doping of 4H SiC by liquid immersion excimer laser irradiation

    SciTech Connect

    Ikeda, Akihiro; Nishi, Koji; Ikenoue, Hiroshi; Asano, Tanemasa

    2013-02-04

    Phosphorus doping of 4H SiC is performed by KrF excimer laser irradiation of 4H SiC immersed in phosphoric acid. Phosphorus is incorporated to a depth of a few tens of nanometers at a concentration of over 10{sup 20}/cm{sup 3} without generating significant crystal defects. Formation of a pn junction diode with an ideality factor of 1.06 is demonstrated.

  12. Ferromagnetism in proton irradiated 4H-SiC single crystal

    SciTech Connect

    Zhou, Ren-Wei; Wang, Hua-Jie; Chen, Wei-Bin; Li, Fei; Liu, Xue-Chao Zhuo, Shi-Yi; Shi, Er-Wei

    2015-04-15

    Room-temperature ferromagnetism is observed in proton irradiated 4H-SiC single crystal. An initial increase in proton dose leads to pronounced ferromagnetism, accompanying with obvious increase in vacancy concentration. Further increase in irradiation dose lowers the saturation magnetization with the decrease in total vacancy defects due to the defects recombination. It is found that divacancies are the mainly defects in proton irradiated 4H-SiC and responsible for the observed ferromagnetism.

  13. Matching Social and Biophysical Scales in Extensive Livestock Production as a Basis for Adaptation to Global Change

    NASA Astrophysics Data System (ADS)

    Sayre, N. F.; Bestelmeyer, B.

    2015-12-01

    Global livestock production is heterogeneous, and its benefits and costs vary widely across global contexts. Extensive grazing lands (or rangelands) constitute the vast majority of the land dedicated to livestock production globally, but they are relatively minor contributors to livestock-related environmental impacts. Indeed, the greatest potential for environmental damage in these lands lies in their potential for conversion to other uses, including agriculture, mining, energy production and urban development. Managing such conversion requires improving the sustainability of livestock production in the face of fragmentation, ecological and economic marginality and climate change. We present research from Mongolia and the United States demonstrating methods of improving outcomes on rangelands by improving the fit between the scales of social and biophysical processes. Especially in arid and semi-arid settings, rangelands exhibit highly variable productivity over space and time and non-linear or threshold dynamics in vegetation; climate change is projected to exacerbate these challenges and, in some cases, diminish overall productivity. Policy and governance frameworks that enable landscape-scale management and administration enable range livestock producers to adapt to these conditions. Similarly, livestock breeds that have evolved to withstand climate and vegetation change improve producers' prospects in the face of increasing variability and declining productivity. A focus on the relationships among primary production, animal production, spatial connectivity, and scale must underpin adaptation strategies in rangelands.

  14. The development of novel LTA4H modulators to selectively target LTB4 generation

    PubMed Central

    Low, Caroline M.; Akthar, Samia; Patel, Dhiren F.; Löser, Stephan; Wong, Chi-Tung; Jackson, Patricia L.; Blalock, J. Edwin; Hare, Stephen A.; Lloyd, Clare M.; Snelgrove, Robert J.

    2017-01-01

    The pro-inflammatory mediator leukotriene B4 (LTB4) is implicated in the pathologies of an array of diseases and thus represents an attractive therapeutic target. The enzyme leukotriene A4 hydrolase (LTA4H) catalyses the distal step in LTB4 synthesis and hence inhibitors of this enzyme have been actively pursued. Despite potent LTA4H inhibitors entering clinical trials all have failed to show efficacy. We recently identified a secondary anti-inflammatory role for LTA4H in degrading the neutrophil chemoattractant Pro-Gly-Pro (PGP) and rationalized that the failure of conventional LTA4H inhibitors may be that they inadvertently prevented PGP degradation. We demonstrate that these inhibitors do indeed fail to discriminate between the dual activities of LTA4H, and enable PGP accumulation in mice. Accordingly, we have developed novel compounds that potently inhibit LTB4 generation whilst leaving PGP degradation unperturbed. These novel compounds could represent a safer and superior class of LTA4H inhibitors for translation into the clinic. PMID:28303931

  15. Key contribution of eIF4H-mediated translational control in tumor promotion

    PubMed Central

    Vaysse, Charlotte; Philippe, Céline; Martineau, Yvan; Quelen, Cathy; Hieblot, Corinne; Renaud, Claire; Nicaise, Yvan; Desquesnes, Aurore; Pannese, Maria; Filleron, Thomas; Escourrou, Ghislaine; Lawson, Malcolm; Rintoul, Robert C.; Delisle, Marie Bernadette; Pyronnet, Stéphane; Brousset, Pierre; Prats, Hervé; Touriol, Christian

    2015-01-01

    Dysregulated expression of translation initiation factors has been associated with carcinogenesis, but underlying mechanisms remains to be fully understood. Here we show that eIF4H (eukaryotic translation initiation factor 4H), an activator of the RNA helicase eIF4A, is overexpressed in lung carcinomas and predictive of response to chemotherapy. In lung cancer cells, depletion of eIF4H enhances sensitization to chemotherapy, decreases cell migration and inhibits tumor growth in vivo, in association with reduced translation of mRNA encoding cell-proliferation (c-Myc, cyclin D1) angiogenic (FGF-2) and anti-apoptotic factors (CIAP-1, BCL-xL). Conversely, each isoform of eIF4H acts as an oncogene in NIH3T3 cells by stimulating transformation, invasion, tumor growth and resistance to drug-induced apoptosis together with increased translation of IRES-containing or structured 5′UTR mRNAs. These results demonstrate that eIF4H plays a crucial role in translational control and can promote cellular transformation by preferentially regulating the translation of potent growth and survival factor mRNAs, indicating that eIF4H is a promising new molecular target for cancer therapy. PMID:26498689

  16. Synthesis of 4H/fcc Noble Multimetallic Nanoribbons for Electrocatalytic Hydrogen Evolution Reaction.

    PubMed

    Fan, Zhanxi; Luo, Zhimin; Huang, Xiao; Li, Bing; Chen, Ye; Wang, Jie; Hu, Yanling; Zhang, Hua

    2016-02-03

    Noble multimetallic nanomaterials, if only consisting of Au, Ag, Pt, and Pd, typically adopt the high-symmetry face-centered cubic (fcc) structure. Here for the first time, by using the 4H/fcc Au@Ag nanoribbons (NRBs) as seeds, we report the synthesis of 4H/fcc trimetallic Au@PdAg core-shell NRBs via the galvanic reaction method under ambient conditions. Moreover, this strategy can also be used to synthesize 4H/fcc trimetallic Au@PtAg and quatermetallic Au@PtPdAg core-shell NRBs. Impressively, for the first time, these alloy shells, i.e., PdAg, PtAg, and PtPdAg, epitaxially grown on the 4H/fcc Au core with novel 4H hexagonal phase were successfully synthesized. Remarkably, the obtained 4H/fcc Au@PdAg NRBs exhibit excellent electrocatalytic activity toward the hydrogen evolution reaction, which is even quite close to that of the commercial Pt black. We believe that our findings here may provide a novel strategy for the crystal-structure-controlled synthesis of advanced functional noble multimetallic nanomaterials with various promising applications.

  17. The development of novel LTA4H modulators to selectively target LTB4 generation

    NASA Astrophysics Data System (ADS)

    Low, Caroline M.; Akthar, Samia; Patel, Dhiren F.; Löser, Stephan; Wong, Chi-Tung; Jackson, Patricia L.; Blalock, J. Edwin; Hare, Stephen A.; Lloyd, Clare M.; Snelgrove, Robert J.

    2017-03-01

    The pro-inflammatory mediator leukotriene B4 (LTB4) is implicated in the pathologies of an array of diseases and thus represents an attractive therapeutic target. The enzyme leukotriene A4 hydrolase (LTA4H) catalyses the distal step in LTB4 synthesis and hence inhibitors of this enzyme have been actively pursued. Despite potent LTA4H inhibitors entering clinical trials all have failed to show efficacy. We recently identified a secondary anti-inflammatory role for LTA4H in degrading the neutrophil chemoattractant Pro-Gly-Pro (PGP) and rationalized that the failure of conventional LTA4H inhibitors may be that they inadvertently prevented PGP degradation. We demonstrate that these inhibitors do indeed fail to discriminate between the dual activities of LTA4H, and enable PGP accumulation in mice. Accordingly, we have developed novel compounds that potently inhibit LTB4 generation whilst leaving PGP degradation unperturbed. These novel compounds could represent a safer and superior class of LTA4H inhibitors for translation into the clinic.

  18. Climate change and livestock system in mountain: Understanding from Gandaki River basin of Nepal Himalaya.

    NASA Astrophysics Data System (ADS)

    Dahal, P.; Shrestha, N. S.; Krakauer, N.; Lakhankar, T.; Panthi, J., Sr.; Pradhanang, S.; Jha, A. K.; Shrestha, M.; Sharma, M.

    2015-12-01

    In recent years climate change has emerged as a source of vulnerability for agro-livestock smallholders in Nepal where people are mostly dependent on rain-fed agriculture and livestock farming for their livelihoods. There is a need to understand and predict the potential impacts of climate change on agro-livestock farmer to develop effective mitigation and adaptation strategies. To understand dynamics of this vulnerability, we assess the farmers' perceptions of climate change, analysis of historical and future projections of climatic parameters and try to understand impact of climate change on livestock system in Gandaki River Basin of Central Nepal. During the period of 1981-2012, as reported by the mountain communities, the most serious hazards for livestock system and agriculture are the increasing trend of temperature, erratic rainfall patterns and increase in drought. Poor households without irrigated land are facing greater risks and stresses than well-off people. Analysis of historical climate data also supports the farmer perception. Result shows that there is increasing trend of temperature but no consistent trend in precipitation but a notable finding is that wet areas are getting wetter and dry areas getting drier. Besides that, there is increase in percentage of warm days and nights with decrease in the cool nights and days. The magnitude of the trend is found to be higher in high altitude. Trend of wet days has found to be increasing with decreasing in rainy days. Most areas are characterized by increases in both severity and frequency of drought and are more evident in recent years. The summers of 2004/05/06/09 and winters of 2006/08/09 were the worst widespread droughts and have a serious impact on livestock since 1981. Future projected change in temperature and precipitation obtained from downscaling the data global model by regional climate model shows that precipitation in central Nepal will change by -8% to 12% and temperature will change by 1

  19. Cost benefit analysis of tuberculosis control in wildlife-livestock interface areas of Southern Zambia.

    PubMed

    Mwacalimba, K K; Mumba, C; Munyeme, M

    2013-06-01

    This paper presents the results of an economic simulation model evaluating the costs and benefits of bovine tuberculosis (bTB) control in a wildlife-livestock interface area of Southern Zambia over a 10 year period, using test and slaughter in livestock and promotion of milk pasteurization amongst livestock keeping communities to reduce the zoonotic transmission of bTB through milk. Expected benefits included increased productivity and health in village resident and transhumant cattle, and averted human bTB treatment costs after the fourth year of the project. In monetary terms, at different bTB prevalence estimates in cattle, the simulation outcome showed that the costs of control never exceeded the few benefits considered over the simulated period. However, the benefits are likely to outweigh the costs if wider implications of bTB in humans (infirmity-related productivity losses), livestock and wildlife (reduced productivity and herd value in cattle and diminished tourism potential from bTB-related wildlife mortalities) are taken into account.

  20. Predictors of performance in a 4-h mountain-bike race.

    PubMed

    Novak, Andrew R; Bennett, Kyle J M; Fransen, Job; Dascombe, Ben J

    2017-04-13

    This study aimed to cross validate previously developed predictive models of mountain biking performance in a new cohort of mountain bikers during a 4-h event (XC4H). Eight amateur XC4H cyclists completed a multidimensional assessment battery including a power profile assessment that consisted of maximal efforts between 6 and 600 s, maximal hand grip strength assessments, a video-based decision-making test as well as a XC4H race. A multiple linear regression model was found to predict XC4H performance with good accuracy (R(2) = 0.99; P < 0.01). This model consisted of [Formula: see text] relative to total cycling mass (body mass including competition clothing and bicycle mass), maximum power output sustained over 60 s relative to total cycling mass, peak left hand grip strength and two-line decision-making score. Previous models for Olympic distance MTB performance demonstrated merit (R(2) = 0.93; P > 0.05) although subtle changes improved the fit, significance and normal distribution of residuals within the model (R(2) = 0.99; P < 0.01), highlighting differences between the disciplines. The high level of predictive accuracy of the new XC4H model further supports the use of a multidimensional approach in predicting MTB performance. The difference between the new, XC4H and previous Olympic MTB predictive models demonstrates subtle differences in physiological requirements and performance predictors between the two MTB disciplines.

  1. Identifying STEM Concepts Associated with Junior Livestock Projects

    ERIC Educational Resources Information Center

    Wooten, Kate; Rayfield, John; Moore, Lori L.

    2013-01-01

    Science, technology, engineering, and mathematics (STEM) education is intended to provide students with a cross-subject, contextual learning experience. To more fully prepare our nation's students to enter the globally competitive workforce, STEM integration allows students to make connections between the abstract concepts learned in core subject…

  2. The welfare of livestock transported by ship.

    PubMed

    Phillips, Clive J C; Santurtun, Eduardo

    2013-06-01

    The transport of livestock by ship is growing in importance, but there are concerns about the welfare impact on the animals. Short sea journeys are usually completed in the vehicles that are used to transport the animals by road, and injury and stress can result. Long sea journeys require offloading of the animals into pens, where they are mixed and provided with feed, water and sometimes artificial ventilation. In addition, animals are often exposed to high stocking densities, elevated temperature and ammonia concentration, as well as noise and changes in photoperiod and light intensity. Mortality rate is the main measure of welfare used by the Australian live export industry for long distance shipments, and the rate is higher at sea compared to the same period of transport on land. Heat stress often challenges livestock when they are transported from cold to hot regions at high stocking densities with no diurnal temperature fluctuation. Sheep cope with heat stress better than cattle, but can still develop respiratory alkalosis if hyperventilation ensues. Bos taurus cattle cope less well with heat stress than Bos indicus breeds. High ammonia concentrations may accumulate on long voyages, causing mucosal irritation and pulmonary inflammation. Some sheep and goats do not adapt to the pellets provided after extensive grazing in Australia, resulting in inanition, often in combination with salmonellosis, which together are the main cause of high mortality rates. Long distance transport may also result in disease transmission to the recipient country and high standards of biosecurity are necessary. It is concluded that there are significant risks to the welfare of livestock caused by transporting them in ships, especially over long distances.

  3. Seroepidemiology of leptospirosis in livestock in Trinidad.

    PubMed

    Suepaul, Sharianne M; Carrington, Christine V; Campbell, Mervyn; Borde, Gustave; Adesiyun, Abiodun Adewale

    2011-02-01

    A study was conducted to determine the seroprevalence of leptospirosis and infecting serovars across livestock (cattle, sheep, goats, and pigs) in Trinidad using the microscopic agglutination test with an international panel of 23 serovars. Of a total of 590 cattle tested, 21.5% were seropositive with agglutinations to 13 of the 23 antigens used in the panel. Icterohaemorrhagiae (9.3%), Sejroe (4.1%), Ballum (4.1%), and Autumnalis (1.9%) were the predominant serogroups detected in the cattle sampled (n = 590). Of 222 sheep tested, 5.0% were seropositive with agglutinations to five serovars belonging to two serogroups. These serogroups were Autumnalis at 2.7%, and Icterohaemorrhagiae at 2.3% of all sheep tested (n = 222). Of a total of 180 goats tested, 3.3% were seropositive, all agglutinating to the Icterohaemorrhagiae serogroup, 1.7% to serovar Copenhageni, 1.1% to serovar Mankarso, and 0.6% to serovar Icterohaemorrhagiae. Among pigs (n = 200), 5.0% were seropositive for five serovars belonging to three serogroups. These serogroups were Icterohaemorrhagiae at 2.5%, Australis at 2%, and Ballum at 0.5%. Overall, age and sex of animals were not significantly associated with leptospirosis with the exception of cattle where age was a significant factor for seropositivity. It was concluded that for livestock, leptospirosis may be an important zoonotic and economic disease, particularly in the case of cattle. It is imperative that the impact of leptospirosis on abortion, stillbirths, and decreased milk production in livestock in the country be assessed.

  4. The roles of livestock in developing countries.

    PubMed

    Herrero, M; Grace, D; Njuki, J; Johnson, N; Enahoro, D; Silvestri, S; Rufino, M C

    2013-03-01

    Livestock play a significant role in rural livelihoods and the economies of developing countries. They are providers of income and employment for producers and others working in, sometimes complex, value chains. They are a crucial asset and safety net for the poor, especially for women and pastoralist groups, and they provide an important source of nourishment for billions of rural and urban households. These socio-economic roles and others are increasing in importance as the sector grows because of increasing human populations, incomes and urbanisation rates. To provide these benefits, the sector uses a significant amount of land, water, biomass and other resources and emits a considerable quantity of greenhouse gases. There is concern on how to manage the sector's growth, so that these benefits can be attained at a lower environmental cost. Livestock and environment interactions in developing countries can be both positive and negative. On the one hand, manures from ruminant systems can be a valuable source of nutrients for smallholder crops, whereas in more industrial systems, or where there are large concentrations of animals, they can pollute water sources. On the other hand, ruminant systems in developing countries can be considered relatively resource-use inefficient. Because of the high yield gaps in most of these production systems, increasing the efficiency of the livestock sector through sustainable intensification practices presents a real opportunity where research and development can contribute to provide more sustainable solutions. In order to achieve this, it is necessary that production systems become market-orientated, better regulated in cases, and socially acceptable so that the right mix of incentives exists for the systems to intensify. Managing the required intensification and the shifts to new value chains is also essential to avoid a potential increase in zoonotic, food-borne and other diseases. New diversification options and improved

  5. Impact of BSE on livestock production system.

    PubMed

    Nardone, A

    2003-09-01

    The small number of BSE cases diagnosed in Italy from January 2001 to 12 September 2001 (a total of 28, one every 9000 head) does not allow for a statistical analysis of the relationship between this disease and the livestock systems. However, some indications can be noted: (a) only dairy cattle, which represent three-quarters of the cattle raised in Italy, are involved; (b) 58% of the cases belong to medium-large farms that breed 27% of all head; (c) 13 out of 28 cases are 5-year-old animals and 26 out of 28 are between 5 and 7 years of age; (d) 15 of 28 cases come from Lombardia, where 27% of Italian dairy cattle are raised. The following factors may have affected the livestock system: (1) trends of beef meat consumption; (2) changes in livestock management; (3) changes in animal feeding; (4) possible effects on selection. A strong decline in beef meat consumption (4 kg/year) has been observed in the UK and other European countries since 1996 (the year of the discovery of the relationship between BSE and nvCJD). In Italy, from January 2001 the consumption of beef meat has declined as well as slaughter: a drop of 31% in the total slaughtered head in the period January-February, a drop of 14% in January-May. A fall in the price of calves has promoted, in some dairy farms, the start of the production of light beef less than one year old (advantages in the marketing of meat favour this initiative), a phenomenon which is not yet well established. Traceability and certification of meat have improved, thanks to breeders' associations and interprofessional agreements. The breeders associations have also started insurance initiatives against BSE risks. In Italy the employment of plant protein meals would increase the total feedstuff consumption by about 7%. Direct effects of BSE could slow down the genetic progress (GP) of cattle populations within breed and country. Indirect effects on GP may also happen as a consequence of an increase in the replacement rate (rr). This

  6. Effect of neutron irradiation on charge collection efficiency in 4H-SiC Schottky diode

    NASA Astrophysics Data System (ADS)

    Wu, Jian; Jiang, Yong; Lei, Jiarong; Fan, Xiaoqiang; Chen, Yu; Li, Meng; Zou, Dehui; Liu, Bo

    2014-01-01

    The charge collection efficiency (CCE) in 4H-SiC Schottky diode is studied as a function of neutron fluence. The 4H-SiC diode was irradiated with fast neutrons of a critical assembly in Nuclear Physics and Chemistry Institute and CCE for 3.5 MeV alpha particles was then measured as a function of the applied reverse bias. It was found from our experiment that an increase of neutron fluence led to a decrease of CCE. In particular, CCE of the diode was less than 1.3% at zero bias after an irradiation at 8.26×1014 n/cm2. A generalized Hecht's equation was employed to analyze CCE in neutron irradiated 4H-SiC diode. The calculations nicely fit the CCE of 4H-SiC diode irradiated at different neutron fluences. According to the calculated results, the extracted electron μτ product (μτ)e and hole μτ product (μτ)h of the irradiated 4H-SiC diode are found to decrease by increasing the neutron fluence.

  7. On the Origin of C4H and CH3OH in Protostellar Envelopes

    NASA Astrophysics Data System (ADS)

    Lindberg, Johan E.; Charnley, Steven B.; Cordiner, Martin A.

    2016-12-01

    The formation pathways of different types of organic molecules in protostellar envelopes and other regions of star formation are subjects of intense current interest. We present here observations of C4H and CH3OH, tracing two distinct groups of interstellar organic molecules, toward 16 protostars in the Ophiuchus and Corona Australis molecular clouds. Together with observations in the literature, we present C4H and CH3OH data from single-dish observations of 40 embedded protostars. We find no correlation between the C4H and CH3OH column densities in this large sample. Based on this lack of correlation, a difference in line profiles between C4H and CH3OH, and previous interferometric observations of similar sources, we propose that the emission from these two molecules is spatially separated, with the CH3OH tracing gas that has been transiently heated to high (˜70-100 K) temperatures and the C4H tracing the cooler large-scale envelope where CH4 molecules have been liberated from ices. These results provide insight in the differentiation between hot corino and warm carbon-chain chemistry in embedded protostars. Based on observations with the Kitt Peak 12 m telescope telescope and the Atacama Pathfinder EXperiment (APEX) telescope. The Kitt Peak 12 m telescope is operated by the Arizona Radio Observatory (ARO), Steward Observatory, University of Arizona. APEX is a collaboration between the Max Planck Institute for Radio Astronomy, the European Southern Observatory, and the Onsala Space Observatory.

  8. CFD Growth of 3C-SiC on 4H/6H Mesas

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Trunek, Andrew J.; Spry, David J.; Powell, J. Anthony; Du, Hui; Skowronski, Marek; Huang, XianRong; Dudley, Michael

    2006-01-01

    This article describes growth and characterization of the highest quality reproducible 3C-SiC heteroepitaxial films ever reported. By properly nucleating 3C-SiC growth on top of perfectly on-axis (0001) 4H-SiC mesa surfaces completely free of atomic scale steps and extended defects, growth of 3C-SiC mesa heterofilms completely free of extended crystal defects can be achieved. In contrast, nucleation and growth of 3C-SiC mesa heterofilms on top of 4H-SiC mesas with atomic-scale steps always results in numerous observable dislocations threading through the 3C-SiC epilayer. High-resolution X-ray diffraction and transmission electron microscopy measurements indicate non-trivial in-plane lattice mismatch between the 3C and 4H layers. This mismatch is somewhat relieved in the step-free mesa case via misfit dislocations confined to the 3C/4H interfacial region without dislocations threading into the overlying 3C-SiC layer. These results indicate that the presence or absence of steps at the 3C/4H heteroepitaxial interface critically impacts the quality, defect structure, and relaxation mechanisms of single-crystal heteroepitaxial 3C-SiC films.

  9. Precision livestock farming technologies for welfare management in intensive livestock systems.

    PubMed

    Berckmans, D

    2014-04-01

    The worldwide demand for meat and animal products is expected to increase by at least 40% in the next 15 years. The first question is how to achieve high-quality, sustainable and safe meat production that can meet this demand. At the same time, livestock production is currently facing serious problems. Concerns about animal health in relation to food safety and human health are increasing. The European Union wants improved animal welfare and has made a significant investment in it. At the same time, the environmental impact of the livestock sector is a major issue. Finally, it is necessary to ask how the farmer, who is the central figure in this process, will make a living from more sustainable livestock production systems. One tool that might provide real opportunities is precision livestock farming (PLF). In contrast to previous approaches, PLF systems aim to offer a real-time monitoring and management system that focuses on improving the life of the animals by warning when problems arise so that the farmer may take immediate action. Continuous, fully automatic monitoring and improvement of animal health and welfare, product yields and environmental impacts should become possible. This paper presents examples of systems that have already been developed in order to demonstrate the potential benefits of this technology.

  10. Synthesis, antifungal activity and docking study of 2-amino-4H-benzochromene-3-carbonitrile derivatives

    NASA Astrophysics Data System (ADS)

    Mirjalili, BiBi Fatemeh; Zamani, Leila; Zomorodian, Kamiar; Khabnadideh, Soghra; Haghighijoo, Zahra; Malakotikhah, Zahra; Ayatollahi Mousavi, Seyyed Amin; Khojasteh, Shaghayegh

    2016-07-01

    Pathogenic fungi are associated with diseases ranging from simple dermatosis to life-threatening infections, particularly in immunocompromised patients. During the past two decades, resistance to established antifungal drugs has increased dramatically and has made it crucial to identify novel antimicrobial compounds. Here, we selected 12 new compounds of 2-amino-4H-benzochromene-3-carbonitrile drivetives (C1-C12) for synthesis by using nano-TiCl4.SiO2 as efficient and green catalyst, then nine of synthetic compounds were evaluated against different species of fungi, positive gram and negative gram of bacteria. Standard and clinical strains of antibiotics sensitive and resistant fungi and bacteria were cultured in appropriate media. Biological activity of the 2-amino-4H-benzochromene-3-carbonitrile derivatives against fungi and bacteries were estimated by the broth micro-dilution method as recommended by clinical and laboratory standard institute (CLSI). In addition minimal fangicidal and bactericial concenteration of the compounds were also determined. Considering our results showed that compound 2-amino-4-(4-methyl benzoate)-4H-benzo[f]chromen-3-carbonitrile (C9) had the most antifungal activity against Aspergillus clavatus, Candida glabarata, Candida dubliniensis, Candida albicans and Candida tropicalis at concentrations ranging from 8 to ≤128 μg/mL. Also compounds 2-amino-4-(3,4-dimethoxyphenyl)-4H-benzo[f]chromen-3-carbonitrile (C4) and 2-amino-4-(4-isopropylphenyl)-4H-benzo[f]chromen-3-carbonitrile (C3) had significant inhibitory activities against Epidermophyton floccosum following 2-amino-4-(4-methylbenzoate)-4H-benzo[f]chromen-3-carbonitrile (C9), respectively. Docking simulation was performed to insert compounds C3, C4 and C9 in to CYP51 active site to determine the probable binding model.

  11. Importance of vector-borne infections in different production systems: bovine trypanosomosis and the innovation dynamics of livestock producers in Senegal.

    PubMed

    Bouyer, F; Bouyer, J; Seck, M T; Sall, B; Dicko, A H; Lancelot, R; Chia, E

    2015-04-01

    In Senegal, a project has been undertaken to eradicate a population of tsetse flies (Glossina palpalis gambiensis) from a prime area for intensifying livestock production--the coastal region of Niayes. The project is intended to remove the constraint of trypanosomosis and allow the ecological intensification of cattle production. A cross-sectional analysis of ten case studies was the inductive phase of an assessment to gauge the impact of removing trypanosomosis on livestock production strategies. The methodology used was comprehensive analysis, with participatory epidemiology tools to understand farmers' rationales. The authors analysed the strategies of three main types of livestock producer (agro-pastoralists, mixed crop/livestock farmers and intensive dairy farmers). The strategies were in line with the farmers' goals and their ability to mobilise the socio-technical network. The risk management of trypanosomosis has been incorporated into livestock management practices through the use of trypanotolerant breeds, medical prophylaxis or placing livestock in low-risk areas. Removing the risk of disease would therefore have a major impact on decisions about the composition and strategic direction of herds. This change in the animal health environment would steer livestock production along different routes of intensification in a highly competitive environment. The indicators of innovation capacity revealed by this study will be used to quantitatively monitor various change scenarios, taking livestock producers' reasoning into account, in order to assess the socio-economic impact of eradicating the tsetse fly population in this area. The methodology presented in the study can be used to understand the impact of controlling other vector-borne infections on the innovation dynamics of livestock producers.

  12. Cathodoluminescence Study of the Properties of Stacking Faults in 4H-SiC Homoepitaxial Layers

    DTIC Science & Technology

    2009-01-01

    Cathodoluminescence study of the properties of stacking faults in 4H- SiC homoepitaxial layers Serguei I. Maximenko,1,a Jaime A. Freitas, Jr.,1 Paul...2009 In-grown stacking faults in n-type 4H- SiC epitaxial layers have been investigated by real-color cathodoluminescence imaging and spectroscopy...carried out at room and liquid helium temperatures. Stacking faults with 8H stacking order were observed, as well as double layer and multilayer 3C- SiC

  13. Transition metal swift heavy ion implantation on 4H-SiC

    NASA Astrophysics Data System (ADS)

    Ali, A. Ashraf; Kumar, J.; Ramakrishnan, V.; Asokan, K.

    2016-03-01

    This work reports on the realization of Quantum Ring (QR) and Quantum Dot (QD) like structures on 4H-SiC through SHI implantation and on their Raman studies. 4H-SiC is SHI implanted with Transition Metal (TM) Ni ion at different fluences. It is observed that a vibrational mode emerges as the result of Ni ion implantation. The E2 (TO) and the A1 (LO) are suppressed as the fluence increases. In this paper Raman and AFM studies have been performed at room temperature and the queer anomalies are addressed so new devices can be fabricated.

  14. Electrical properties of extended defects in 4H-SiC investigated by photoinduced current measurements

    NASA Astrophysics Data System (ADS)

    Privitera, Stefania M. S.; Litrico, Grazia; Camarda, Massimo; Piluso, Nicolò; La Via, Francesco

    2017-03-01

    We study the correlation between crystal quality and electrical transport in 4H-SiC by micro-photoluminescence and laser-beam-induced photocurrent measurements. A focused HeCd laser at 325 nm has been employed to simultaneously measure, with a spatial resolution of a few microns, both the photoluminescence and current–voltage characteristics of 4H-SiC Schottky diodes. We found that the laser-induced photocurrent acquired along a defect can give information on its spatial distribution in depth and that the local minority carrier lifetime and generation depend on the type of stacking fault, both decreasing for defects with deeper intragap levels.

  15. Connecting Kids to the Universe: Partnering with 4--H Youth Development to Pilot Afterschool Universe in New York

    NASA Astrophysics Data System (ADS)

    Schaff, N.

    2008-11-01

    To offer effective astrophysics outreach education, developmentally appropriate hands-on activities that develop conceptual understanding and create excitement about science and careers are needed. The new NASA Afterschool Universe Program is ideal to enhance astronomy and astrophysics outreach. Afterschool Universe is a comprehensive project that builds a strong conceptual understanding of the Universe beyond the solar system for out-of-school groups at the middle school level. Students at this age are fascinated by mysteries (to them) of the universe, but are introduced primarily to the Solar System in school. We determined that access to materials and training would be essential to successful implementation of Afterschool Universe. Therefore, we secured funding from the Chandra EPO program to develop kits and implement five regional workshops in collaboration with 4--H Youth Development in New York State during 2008, in preparation for the International Year of Astronomy.

  16. 36 CFR 262.10 - Impoundment and disposal of unauthorized livestock.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... unauthorized livestock. 262.10 Section 262.10 Parks, Forests, and Public Property FOREST SERVICE, DEPARTMENT OF... unauthorized livestock. Unauthorized livestock or livestock in excess of those authorized by a grazing permit... officer determines that such livestock use is occurring, has definite knowledge of the kind of...

  17. Effects of livestock wastes on small illinois streams: Lower Kaskaskia river basin and upper little wabash river basins, summer 1991

    SciTech Connect

    Hite, R.L.; Bickers, C.A.; King, M.M.; Brockamp, D.W.

    1992-07-01

    In early 1991, the Illinois Environmental Protection Agency (IEPA) initiated an investigation to evaluate livestock waste runoff in southern Illinois. The primary objectives of this survey were to document stream quality impairments caused by livestock waste runoff, and ultimately, the need for better waste management practices, waste management systems, and funding for such systems. Information provided by Soil Conservation Service (SCS) and IEPA Agricultural staff identified an area in Clinton and Bond Counties in the Kaskaskia River basin and several upper Little Wabash River basin tributaries in Effingham and Cumberland Counties as candidate project areas.

  18. Maine 4-H Afterschool Academy--A Professional Development Opportunity for Out-of-School-Time Providers

    ERIC Educational Resources Information Center

    Lobley, Jennifer; Ouellette, Kristy L.

    2013-01-01

    The Maine 4-H Afterschool Academy trained 369 after-school and out of school time providers in 2011. This easy-to-adapt professional development opportunity used blended learning, a combination of in-person and Web-based opportunities. Providers successfully learned concepts and practical knowledge regarding 4-H, specifically 4-H Science. In…

  19. Microstructures of InN film on 4H-SiC (0001) substrate grown by RF-MBE

    NASA Astrophysics Data System (ADS)

    Jantawongrit, P.; Sanorpim, S.; Yaguchi, H.; Orihara, M.; Limsuwan, P.

    2015-08-01

    InN film was grown on 4H-SiC (0001) substrate by RF plasma-assisted molecular beam epitaxy (RF-MBE). Prior to the growth of InN film, an InN buffer layer with a thickness of ∼5.5 nm was grown on the substrate. Surface morphology, microstructure and structural quality of InN film were investigated. Micro-structural defects, such as stacking faults and anti-phase domain in InN film were carefully investigated using transmission electron microscopy (TEM). The results show that a high density of line contrasts, parallel to the growth direction (c-axis), was clearly observed in the grown InN film. Dark field TEM images recorded with diffraction vectors g=11\\bar{2}0 and g = 0002 revealed that such line contrasts evolved from a coalescence of the adjacent misoriented islands during the initial stage of the InN nucleation on the substrate surface. This InN nucleation also led to a generation of anti-phase domains. Project supported by the Thailand Center of Excellence in Physics (ThEP) and the King Mongkut's University of Technology Thonburi under The National Research University Project. One of the authors (S. Sanorpim) was supported by the National Research Council of Thailand (NRCT) and the Thai Government Stimulus Package 2 (TKK2555), under the Project for Establishment of Comprehensive Center for Innovative Food, Health Products and Agriculture.

  20. 4-H Tractor Operator Program Teaches Employability Skills and Safety to Youth

    ERIC Educational Resources Information Center

    Barrett, Debra K.

    2013-01-01

    For Michigan State University Extension, the Berrien County 4-H Tractor Operator Program has provided tractor safety education to teens for over 30 years. The certification training satisfies current requirements for operation of a 20 PTO HP or greater agricultural tractor by 14- and 15-year-old youth employed on property "not" owned,…

  1. Possession, Transportation, and Use of Firearms by Older Youth in 4-H Shooting Sports Programs

    ERIC Educational Resources Information Center

    White, David J.; Williver, S. Todd

    2014-01-01

    Thirty years ago we would think nothing of driving to school with a jackknife in our pocket or rifle in the gun rack. Since then, the practices of possessing, transporting, and using firearms have been limited by laws, rules, and public perception. Despite restrictions on youth, the Youth Handgun Safety Act does afford 4-H shooting sports members…

  2. An Evaluation of the 4-H "Health Rocks" Program: Implications for Program Improvement

    ERIC Educational Resources Information Center

    Self, Carlton; Morgan, A. Christian; Fuhrman, Nicholas E.; Navarro, Maria

    2013-01-01

    The National 4-H Council developed the Health Rocks substance abuse educational program to prevent youth from engaging in risky behaviors. The program was presented in 2010 to more than 8,000 middle school youth in Georgia. A post-then-pre evaluation was conducted with youth who completed 10 hours of instruction to determine if changes in youth…

  3. A Beach and Dune Community. 4-H Marine Science. Member's Guide. Activity I. MSp 1.

    ERIC Educational Resources Information Center

    Auburn Univ., AL. Cooperative Extension Service.

    The investigation in this booklet is designed to provide 4-H members with opportunities to identify common plants and animals found on beaches and sand dunes and to determine the role of the plants and animals in this community. Learners are provided with a picture of a hypothetical beach and sand dune and a list of organisms (included in the…

  4. Factors Related to Motivating Adult Somalis with Refugee Status to Volunteer for 4-H

    ERIC Educational Resources Information Center

    Mason, Mitchell D.; Ouellette, Kristy L.

    2016-01-01

    Focus group interviews were held with adult Somali immigrants to assess their likelihood of volunteering for 4-H in Maine. This qualitative study was undertaken to identify best practices for engaging the growing Somali-Mainer population as a volunteer base. Results of the study demonstrate that Somali immigrant adults are willing to volunteer for…

  5. A novel synthesis of 4H-chromen-4-ones via intramolecular wittig reaction

    PubMed

    Kumar; Bodas

    2000-11-30

    The acylphosphoranes formed in a sequential manner from the reaction of the silyl ester of O-acyl(aroyl)salicylic acids and (trimethylsilyl)methylenetriphenylphosphorane undergo intramolecular Wittig cyclization on the ester carbonyl to afford the 4H-chromen-4-ones in good to excellent yields.

  6. N-[4-(Dimethyl-amino)-benzyl-idene]-4H-1,2,4-triazol-4-amine.

    PubMed

    Zhou, Hui-Liang; Zhang, Xiao-Min

    2012-05-01

    The title compound, C(11)H(13)N(5), is a Schiff base synthesized by the reaction of 4-amino-4H-1,2,4-triazole and 4-(dimethyl-amino)-benzaldehyde. The dihedral angle between the benzene and triazole rings is 43.09 (11)°. The crystal structure displays weak C-H⋯N inter-actions.

  7. Temperature Dependence of Attenuation of Coplanar Waveguide on 4H High Resistivity SIC Through 540C

    NASA Technical Reports Server (NTRS)

    Ponchak, G. E.; Schwartz, Z.; Alterovitz, S. A.; Downey, A. N.; Freeman, J. C.

    2003-01-01

    For the first time, the temperature and frequency dependence of the attenuation of a Coplanar Waveguide (CPW) on 4H, High Resistivity Sic substrate is reported. The low frequency attenuation increases by 2 dB/cm at 500 C and the high frequency attenuation increases by 3.3 dB/cm at 500 C compared to room temperature.

  8. 4-H Chickquest: Connecting Agri-Science with STEM Standards in Urban Schools

    ERIC Educational Resources Information Center

    Horton, Robert L.; Krieger, Jackie; Halasa, Katrina

    2013-01-01

    While young students are more capable of scientific inquiry than previously believed, elementary school teachers are often inexperienced in and lack confidence with teaching science. ChickQuest is a 4-H-created embryology curriculum for third-graders that meets Ohio state science standards, teaches STEM skills, and promotes ongoing interaction…

  9. Diastereoselectivity in prebiotically relevant 5(4H)-oxazolone-mediated peptide couplings.

    PubMed

    Beaufils, Damien; Danger, Grégoire; Boiteau, Laurent; Rossi, Jean-Christophe; Pascal, Robert

    2014-03-21

    A stereochemical study of a potentially prebiotic peptide-forming reaction was carried out as the first part of a systems chemistry investigation of potential paths for symmetry breaking. Substantial diastereomeric excesses result from a fast epimerization of the 5(4H)-oxazolone intermediate in aqueous solution.

  10. Formation of low-temperature cirrus from H2SO4/H2O aerosol droplets.

    PubMed

    Bogdan, A; Molina, M J; Sassen, K; Kulmala, M

    2006-11-23

    We present experimental results obtained with a differential scanning calorimeter (DSC) that indicate the small ice particles in low-temperature cirrus clouds are not completely solid but rather coated with an unfrozen H2SO4/H2O overlayer. Our results provide a new look on the formation, development, and microphysical properties of low-temperature cirrus clouds.

  11. Pennsylvania Youth in Action: 4-H Community Development. Adult Leader's Guide.

    ERIC Educational Resources Information Center

    Pennsylvania State Univ., University Park. Dept. of Agricultural and Extension Education.

    Designed to assist leaders in their roles as catalysts, advisors, and resource persons for the Pennsylvania Youth in Action 4-H Community Development program, the guide provides complementary educational, craft, and recreation suggestions to enhance student workbooks for three community development activity units. The first section focuses on the…

  12. Louisiana 4-H Seeds of Service School Gardens: A Descriptive View

    ERIC Educational Resources Information Center

    Cater, Melissa; Fox, Janet; Fletcher, Bobby Jr.

    2012-01-01

    Louisiana 4-H Seeds of Service School Gardens, a K-12 Learn and Serve Grant program, provides a descriptive view of how school gardens along with classroom instruction link curriculum to outdoor classrooms. The purpose of the process evaluation was to describe curriculum implementation fidelity, reach of the gardening program to participants, use…

  13. A Historical Review of Leadership Development in the FFA and 4-H

    ERIC Educational Resources Information Center

    Hoover, Tracy S.; Scholl, Jan F.; Dunigan, Anne H.; Mamontova, Nadezhda

    2007-01-01

    FFA and 4-H are two youth-based organizations that cite leadership development as a key foundational component. The purpose of this study was to review and document the historical development of leadership events and activities in both programs. Evidence can be found of leadership development in schools, conferences, and camps. Leadership-related…

  14. Bufexamac ameliorates LPS-induced acute lung injury in mice by targeting LTA4H

    PubMed Central

    Xiao, Qiang; Dong, Ningning; Yao, Xue; Wu, Dang; Lu, Yanli; Mao, Fei; Zhu, Jin; Li, Jian; Huang, Jin; Chen, Aifang; Huang, Lu; Wang, Xuehai; Yang, Guangxiao; He, Guangyuan; Xu, Yong; Lu, Weiqiang

    2016-01-01

    Neutrophils play an important role in the occurrence and development of acute lung injury (ALI). Leukotriene B4 (LTB4), a hydrolysis product of epoxide leukotriene A4 (LTA4) catalyzed by LTA4 hydrolase (LTA4H), is one of the most potent chemoattractants for neutrophil. Bufexamac is a drug widely used as an anti-inflammatory agent on the skin, however, the mechanism of action is still not fully understood. In this study, we found bufexamac was capable of specifically inhibiting LTA4H enzymatic activity and revealed the mode of interaction of bufexamac and LTA4H using X-ray crystallography. Moreover, bufexamac significantly prevented the production of LTB4 in neutrophil and inhibited the fMLP-induced neutrophil migration through inhibition of LTA4H. Finally, bufexamac significantly attenuated lung inflammation as reflected by reduced LTB4 levels and weakened neutrophil infiltration in bronchoalveolar lavage fluid from a lipopolysaccharide-induced ALI mouse model. In summary, our study indicates that bufexamac acts as an inhibitor of LTB4 biosynthesis and may have potential clinical applications for the treatment of ALI. PMID:27126280

  15. An Occupational Analysis Comparing 4-H Youth Development Agents Serving Traditional and Non-Traditional Clientele.

    ERIC Educational Resources Information Center

    Borden, Lynne M.; Harris, William

    1998-01-01

    Six 4-H agents working with traditional clients and six with nontraditional clients participated in a DACUM (Developing a Curriculum) analysis of job tasks. They performed similar duties but the nontraditional group spent more time assessing individual members; the traditional group focused more on program management. (SK)

  16. The Value of 4-H Judging Teams--Missouri Dairy Judging Alumni Survey

    ERIC Educational Resources Information Center

    Deaver, Karla; Probert, Ted

    2016-01-01

    Former Missouri 4-H Dairy Judging Team members responded to a survey about life skills development and the value of the judging team experience. Results of the survey indicate that judging team experience was highly influential in the development of communication, public speaking, and presentation skills. Respondents also indicated that judging…

  17. Participant Comfort with and Application of Inquiry-Based Learning: Results from 4-H Volunteer Training

    ERIC Educational Resources Information Center

    Haugen, Heidi; Stevenson, Anne; Meyer, Rebecca L.

    2016-01-01

    This article explores how a one-time training designed to support learning transfer affected 4-H volunteers' comfort levels with the training content and how comfort levels, in turn, affected the volunteers' application of tools and techniques learned during the training. Results of a follow-up survey suggest that the training participants…

  18. Performance statistics of the FORTRAN 4 /H/ library for the IBM system/360

    NASA Technical Reports Server (NTRS)

    Clark, N. A.; Cody, W. J., Jr.; Hillstrom, K. E.; Thieleker, E. A.

    1969-01-01

    Test procedures and results for accuracy and timing tests of the basic IBM 360/50 FORTRAN 4 /H/ subroutine library are reported. The testing was undertaken to verify performance capability and as a prelude to providing some replacement routines of improved performance.

  19. National Invitational Training Conference on Working with Youth with Special Needs Through 4-H.

    ERIC Educational Resources Information Center

    Worden, Phyllis, Comp.

    A conference set up to exchange and disseminate ideas and information on the mentally retarded is presented. Specific purposes of the conference are: (1) to promote appreciation and understanding of handicapped youth--mentally retarded, and physically and visually handicapped youth, (2) to promote knowledge of on-going programs through 4-H with…

  20. Diffusion of Social Media among County 4-H Programs in Tennessee

    ERIC Educational Resources Information Center

    Bowen, Rebekah D.; Stephens, Carrie A.; Childers, Courtney C.; Avery, Elizabeth J.; Stripling, Christopher T.

    2013-01-01

    Over the past decade, Cooperative Extension and 4-H professionals have been faced with the decision of whether to adopt new communication technologies such as social media. Research on social media and Cooperative Extension has identified risks and barriers to adoption; however, many Cooperative Extension professionals believe that social media…

  1. High-quality permanent draft genome sequence of Ensifer meliloti strain 4H41, an effective salt- and drought-tolerant microsymbiont of Phaseolus vulgaris

    DOE PAGES

    Mhamdi, Ridha; Ardley, Julie; Tian, Rui; ...

    2015-07-02

    We report that Ensifer meliloti 4H41 is an aerobic, motile, Gram-negative, non-spore-forming rod that can exist as a soil saprophyte or as a legume microsymbiont of common bean (Phaseolus vulgaris). Strain 4H41 was isolated in 2002 from root nodules of P. vulgaris grown in South Tunisia from the oasis of Rjim-Maatoug. Strain 4H41 is salt- and drought-tolerant and highly effective at fixing nitrogen with P. vulgaris. Here we describe the features of E. meliloti 4H41, together with genome sequence information and its annotation. The 6,795,637 bp high-quality permanent draft genome is arranged into 47 scaffolds of 47 contigs containing 6,350more » protein-coding genes and 72 RNA-only encoding genes, and is one of the rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project proposal.« less

  2. High-quality permanent draft genome sequence of Ensifer meliloti strain 4H41, an effective salt- and drought-tolerant microsymbiont of Phaseolus vulgaris

    SciTech Connect

    Mhamdi, Ridha; Ardley, Julie; Tian, Rui; Seshadri, Rekha; Reddy, T. B. K.; Pati, Amrita; Woyke, Tanja; Markowitz, Victor; Ivanova, Natalia; Kyrpides, Nikos; Reeve, Wayne

    2015-07-02

    We report that Ensifer meliloti 4H41 is an aerobic, motile, Gram-negative, non-spore-forming rod that can exist as a soil saprophyte or as a legume microsymbiont of common bean (Phaseolus vulgaris). Strain 4H41 was isolated in 2002 from root nodules of P. vulgaris grown in South Tunisia from the oasis of Rjim-Maatoug. Strain 4H41 is salt- and drought-tolerant and highly effective at fixing nitrogen with P. vulgaris. Here we describe the features of E. meliloti 4H41, together with genome sequence information and its annotation. The 6,795,637 bp high-quality permanent draft genome is arranged into 47 scaffolds of 47 contigs containing 6,350 protein-coding genes and 72 RNA-only encoding genes, and is one of the rhizobial genomes sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project proposal.

  3. Wolf-livestock interactions in the northern Rocky Mountains

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Since reintroduction in 1995, gray wolf populations in the northern Rocky Mountains have increased dramatically. Although rough tallies of livestock death/injury losses resulting from wolf predation are made each year, we know almost nothing about the indirect effects of wolf-livestock interactions...

  4. 9 CFR 313.1 - Livestock pens, driveways and ramps.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... animal may be injured shall be repaired. (b) Floors of livestock pens, ramps, and driveways shall be constructed and maintained so as to provide good footing for livestock. Slip resistant or waffled floor... the opinion of the inspector, to protect them from the adverse climatic conditions of the locale...

  5. 36 CFR 2.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Livestock use and agriculture. 2.60 Section 2.60 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.60 Livestock use and agriculture. (a)...

  6. 36 CFR 1002.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Livestock use and agriculture. 1002.60 Section 1002.60 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.60 Livestock use and agriculture. (a) The running-at-large, herding,...

  7. 36 CFR 1002.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 3 2010-07-01 2010-07-01 false Livestock use and agriculture. 1002.60 Section 1002.60 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.60 Livestock use and agriculture. (a) The running-at-large, herding,...

  8. 36 CFR 2.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Livestock use and agriculture. 2.60 Section 2.60 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.60 Livestock use and agriculture. (a)...

  9. 36 CFR 1002.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Livestock use and agriculture. 1002.60 Section 1002.60 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.60 Livestock use and agriculture. (a) The running-at-large, herding,...

  10. 36 CFR 2.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Livestock use and agriculture. 2.60 Section 2.60 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.60 Livestock use and agriculture. (a)...

  11. 36 CFR 1002.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Livestock use and agriculture. 1002.60 Section 1002.60 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.60 Livestock use and agriculture. (a) The running-at-large, herding,...

  12. 36 CFR 2.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Livestock use and agriculture. 2.60 Section 2.60 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.60 Livestock use and agriculture. (a)...

  13. 36 CFR 1002.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Livestock use and agriculture. 1002.60 Section 1002.60 Parks, Forests, and Public Property PRESIDIO TRUST RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 1002.60 Livestock use and agriculture. (a) The running-at-large, herding,...

  14. 36 CFR 2.60 - Livestock use and agriculture.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Livestock use and agriculture. 2.60 Section 2.60 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR RESOURCE PROTECTION, PUBLIC USE AND RECREATION § 2.60 Livestock use and agriculture. (a)...

  15. The effect of multiple plant toxins on livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When livestock are poisoned by plants in a range setting, there is normally more than one poisonous plant in that area. Additionally, many plants contain more than one compound that is toxic to livestock. Frequently, much is known regarding the toxicity of the individual plants and their individual ...

  16. 7 CFR 760.209 - Livestock payment calculations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... livestock organizations and the Cooperative Extension Service for the State. (3) National payment rates to....209 Agriculture Regulations of the Department of Agriculture (Continued) FARM SERVICE AGENCY... eligible adverse weather or eligible loss condition, as provided in § 760.203(d)(1); (2) Livestock...

  17. Agricultural Development Workers Training Manual. Volume IV. Livestock.

    ERIC Educational Resources Information Center

    Bacon, Neil; And Others

    This training manual, the last volume in a four-volume series for use in training Peace Corps workers, deals with livestock. The first chapter provides suggested guidelines for setting up and carrying out the livestock component of the agricultural development worker training course. Included in the second chapter are lesson plans covering the…

  18. 19 CFR 4.71 - Inspection of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Inspection of livestock. 4.71 Section 4.71 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Foreign Clearances § 4.71 Inspection of livestock. A proper...

  19. 25 CFR 168.7 - Kind of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Kind of livestock. 168.7 Section 168.7 Indians BUREAU OF... LANDS AREA § 168.7 Kind of livestock. Unless determined otherwise by the Area Director for conservation purposes, the Hopi Tribe may determine, subject to the authorized carrying capacity, the kind of...

  20. Radiation effects on livestock: physiological effects, dose response

    SciTech Connect

    Bell, M.C.

    1985-06-01

    Farm livestock show no measurable effects from being exposed to ionizing radiation unless the level is greatly in excess of the natural background radiation. Possible sources of ionizing radiation which might affect livestock or contribute to radioactivity in the food chain to humans are reactor accidents, fuel reprocessing plant accidents and thermonuclear explosions. Most data on ionizing radiation effects on livestock are from whole body gamma doses near the LD 50/60 level. However, grazing livestock would be subjected to added beta exposure from ingested and skin retained radioactive particles. Results of attempts to simulate exposure of the Hereford cattle at Alamogardo, NM show that cattle are more sensitive to ingested fallout radiation than other species. Poultry LD 50/60 for gamma exposure is about twice the level for mammals, and swine appear to have the most efficient repair system being able to withstand the most chronic gamma exposure. Productivity of most livestock surviving an LD 50/60 exposure is temporarily reduced and longterm effects are small. Livestock are good screeners against undesirables in our diet and with the exception of radiosotopes of iodine in milk, very little fission product radioactivity would be expected to be transferred through the food chain in livestock products for humans. Feeding of stored feed or moving livestock to uncontaminated pastures would be the best protective action to follow. 29 references.

  1. 7 CFR 760.303 - Eligible livestock producer.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE SPECIAL PROGRAMS INDEMNITY PAYMENT PROGRAMS Livestock Forage Disaster Program § 760.303 Eligible... must: (1) During the 60 days prior to the beginning date of a qualifying drought or fire, own, cash or... Federal agency from grazing the normal permitted livestock due to a qualifying fire. (b) The...

  2. Virtual herding for flexible livestock management - a review

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Free-ranging livestock play a pivotal role globally in the conversion of plant tissue into products and services that support man’s many and changing lifestyles. With domestication came the task of providing livestock with an adequate plane of nutrition while simultaneously managing vegetation for s...

  3. 7 CFR 205.236 - Origin of livestock.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.236 Origin of livestock. (a) Livestock products that are to be sold, labeled, or represented as organic must be...

  4. 7 CFR 205.236 - Origin of livestock.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.236 Origin of livestock. (a) Livestock products that are to be sold, labeled, or represented as organic must be...

  5. 7 CFR 205.236 - Origin of livestock.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.236 Origin of livestock. (a) Livestock products that are to be sold, labeled, or represented as organic must be...

  6. 7 CFR 205.236 - Origin of livestock.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.236 Origin of livestock. (a) Livestock products that are to be sold, labeled, or represented as organic must be...

  7. 7 CFR 205.236 - Origin of livestock.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) ORGANIC FOODS PRODUCTION ACT PROVISIONS NATIONAL ORGANIC PROGRAM Organic Production and Handling Requirements § 205.236 Origin of livestock. (a) Livestock products that are to be sold, labeled, or represented as organic must be...

  8. Experimental Durability Testing of 4H SiC JFET Integrated Circuit Technology at 727 C

    NASA Technical Reports Server (NTRS)

    Spry, David; Neudeck, Phil; Chen, Liangyu; Chang, Carl; Lukco, Dorothy; Beheim, Glenn M

    2016-01-01

    We have reported SiC integrated circuits (IC's) with two levels of metal interconnect that have demonstrated prolonged operation for thousands of hours at their intended peak ambient operational temperature of 500 C [1, 2]. However, it is recognized that testing of semiconductor microelectronics at temperatures above their designed operating envelope is vital to qualification. Towards this end, we previously reported operation of a 4H-SiC JFET IC ring oscillator on an initial fast thermal ramp test through 727 C [3]. However, this thermal ramp was not ended until a peak temperature of 880 C (well beyond failure) was attained. Further experiments are necessary to better understand failure mechanisms and upper temperature limit of this extreme-temperature capable 4H-SiC IC technology. Here we report on additional experimental testing of custom-packaged 4H-SiC JFET IC devices at temperatures above 500 C. In one test, the temperature was ramped and then held at 727 C, and the devices were periodically measured until electrical failure was observed. A 4H-SiC JFET on this chip electrically functioned with little change for around 25 hours at 727 C before rapid increases in device resistance caused failure. In a second test, devices from our next generation 4H-SiC JFET ICs were ramped up and then held at 700 C (which is below the maximum deposition temperature of the dielectrics). Three ring oscillators functioned for 8 hours at this temperature before degradation. In a third experiment, an alternative die attach of gold paste and package lid was used, and logic circuit operation was demonstrated for 143.5 hours at 700 C.

  9. High efficiency 4H-SiC betavoltaic power sources using tritium radioisotopes

    SciTech Connect

    Thomas, Christopher; Portnoff, Samuel; Spencer, M. G.

    2016-01-04

    Realization of an 18.6% efficient 4H-silicon carbide (4H-SiC) large area betavoltaic power source using the radioisotope tritium is reported. A 200 nm 4H-SiC P{sup +}N junction is used to collect high-energy electrons. The electron source is a titanium tritide (TiH{sup 3}{sub x}) foil, or an integrated titanium tritide region formed by the diffusion of tritium into titanium. The specific activity of the source is directly measured. Dark current measured under short circuit conditions was less than 6.1 pA/cm{sup 2}. Samples measured with an external tritium foil produced an open circuit voltage of 2.09 V, short circuit current of 75.47 nA/cm{sup 2}, fill factor of 0.86, and power efficiency of 18.6%. Samples measured with an integrated source produced power efficiencies of 12%. Simulations were done to determine the beta spectrum (modified by self absorption) exiting the source and the electron hole pair generation function in the 4H-SiC. The electron-hole pair generation function in 4H-SiC was modeled as a Gaussian distribution, and a closed form solution of the continuity equation was used to analyze the cell performance. The effective surface recombination velocity in our samples was found to be 10{sup 5}–10{sup 6 }cm/s. Our analysis demonstrated that the surface recombination dominates the performance of a tritium betavoltaic device but that using a thin P{sup +}N junction structure can mitigate some of the negative effects.

  10. Anaerobic digestion of livestock manures in the US: A current opportunities casebook

    SciTech Connect

    Lusk, P.D.

    1995-10-01

    Growth and concentration of the livestock industry creates new opportunities for proper disposal of the large quantities of manures generated at dairy, swine, and poultry farms. One manure management system provides not only pollution prevention but also converts a problem into a new profit center. Economic evaluations and case studies of operating systems indicate that the anaerobic digestion of livestock manures is a commercially-available bioconversion technology with considerable potential for providing profitable co-products, including a renewable fuel. An introduction to the engineering economies of these technologies is provided, based on estimates of digesters that generate electricity from the recovered methane. Regression models used to estimate digester cost and internal rate of return are developed from the evaluations. Case studies of operating digesters, including project and maintenance histories, and the operator`s ``lessons learned``, are provided as a reality check.

  11. Groundwater pollution by nitrates from livestock wastes.

    PubMed

    Goldberg, V M

    1989-11-01

    Utilization of wastes from livestock complexes for irrigation involves the danger of groundwater pollution by nitrates. In order to prevent and minimize pollution, it is necessary to apply geological-hydrogeological evidence and concepts to the situation of wastewater irrigation for the purposes of studying natural groundwater protectiveness and predicting changes in groundwater quality as a result of infiltrating wastes. The procedure of protectiveness evaluation and quality prediction is described. With groundwater pollution by nitrate nitrogen, the concentration of ammonium nitrogen noticeably increases. One of the reasons for this change is the process of denitrification due to changes in the hydrogeochemical conditions in a layer. At representative field sites, it is necessary to collect systematic stationary observations of the concentrations of nitrogenous compounds in groundwater and changes in redox conditions and temperature.

  12. Groundwater pollution by nitrates from livestock wastes

    SciTech Connect

    Goldberg, V.M. )

    1989-11-01

    Utilization of wastes from livestock complexes for irrigation involves the danger of groundwater pollution by nitrates. In order to prevent and minimize pollution, it is necessary to apply geological-hydrogeological evidence and concepts to the situation of wastewater irrigation for the purposes of studying natural groundwater protectiveness and predicting changes in groundwater quality as a result of infiltrating wastes. The procedure of protectiveness evaluation and quality prediction is described. With groundwater pollution by nitrate nitrogen, the concentration of ammonium nitrogen noticeably increases. One of the reasons for this change is the process of denitrification due to changes in the hydrogeochemical conditions in a layer. At representative field sites, it is necessary to collect systematic stationary observations of the concentrations of nitrogenous compounds in groundwater and changes in redox conditions and temperature.

  13. Prebiotics in Companion and Livestock Animal Nutrition

    NASA Astrophysics Data System (ADS)

    Barry, Kathleen A.; Vester, Brittany M.; Fahey, George C.

    Prebiotic supplementation of animal diets began in an attempt to increase concentrations of beneficial intestinal microbiota. It was understood that prebiotics inhibited growth of intestinal pathogens and decreased concentrations of stool odor-causing metabolites. Since the use of prebiotics began, several countries have banned the use of antimicrobials in livestock animal feeds, and several more have placed restrictions on the quantity of antimicrobials that can be used. Prebiotic supplementation has become increasingly popular as the body of evidence supporting its use continues to grow. As this literature expands, the number of potential prebiotic substances has grown beyond those that are naturally occurring, such as those found in chicory and yeast products, to include a large number of synthetic or chemically/enzymatically manufactured prebiotics.

  14. Human pharmacology of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) after repeated doses taken 4 h apart Human pharmacology of MDMA after repeated doses taken 4 h apart.

    PubMed

    Farré, Magí; Tomillero, Angels; Pérez-Mañá, Clara; Yubero, Samanta; Papaseit, Esther; Roset, Pere-Nolasc; Pujadas, Mitona; Torrens, Marta; Camí, Jordi; de la Torre, Rafael

    2015-10-01

    3,4-Methylenedioxymethamphetamine (MDMA, ecstasy) is a popular psychostimulant, frequently associated with multiple administrations over a short period of time. Repeated administration of MDMA in experimental settings induces tolerance and metabolic inhibition. The aim is to determine the acute pharmacological effects and pharmacokinetics resulting from two consecutive 100mg doses of MDMA separated by 4h. Ten male volunteers participated in a randomized, double-blind, crossover, placebo-controlled trial. The four conditions were placebo plus placebo, placebo plus MDMA, MDMA plus placebo, and MDMA plus MDMA. Outcome variables included pharmacological effects and pharmacokinetic parameters. After a second dose of MDMA, most effects were similar to those after a single dose, despite a doubling of MDMA concentrations (except for systolic blood pressure and reaction time). After repeated MDMA administration, a 2-fold increase was observed in MDMA plasma concentrations. For a simple dose accumulation MDMA and MDA concentrations were higher (+23.1% Cmax and +17.1% AUC for MDMA and +14.2% Cmax and +10.3% AUC for MDA) and HMMA and HMA concentrations lower (-43.3% Cmax and -39.9% AUC for HMMA and -33.2% Cmax and -35.1% AUC for HMA) than expected, probably related to MDMA metabolic autoinhibition. Although MDMA concentrations doubled after the second dose, most pharmacological effects were similar or slightly higher in comparison to the single administration, except for systolic blood pressure and reaction time which were greater than predicted. The pharmacokinetic-effects relationship suggests that when MDMA is administered at a 4h interval there exists a phenomenon of acute tolerance to its effects.

  15. Effects of ionizing radiation on struvite crystallization of livestock wastewater

    NASA Astrophysics Data System (ADS)

    Kim, Tak-Hyun; Nam, Yun-Ku; Joo Lim, Seung

    2014-04-01

    Livestock wastewater is generally very difficult to be treated by conventional wastewater treatment techniques because it contains high-strength organics (COD), ammonium (NH4+), phosphate (PO43-) and suspended solids. Struvite crystallization has been recently studied for the simultaneous removal of NH4+ and PO43-. In this study, gamma ray irradiation was carried out prior to struvite crystallization of the anaerobically digested livestock wastewater. The effects of gamma ray irradiation on the struvite crystallization of livestock wastewater were investigated. As a result, gamma ray irradiation can decrease the concentration of COD, NH4+ and PO43- contained in the livestock wastewater. This results in not only an enhancement of the struvite crystallization efficiency but also a decrease in the chemical demands for the struvite crystallization of livestock wastewater.

  16. Clinical assessment of selenium status of livestock.

    PubMed

    Stowe, H D; Herdt, T H

    1992-12-01

    Assessment of the selenium status of livestock is an important aspect of production medicine, but variations in reported values between laboratories and between methods may be > 30%. Reliable interpretations require considerable experience with an assay and an extensive database from field and research case samples of a variety of species. The Michigan State University Animal Health Diagnostic Laboratory (MSU-ADHL) has offered Se analyses by acid-digestion and fluorometric detection since 1982. This laboratory expects serum Se values (nanograms per milliliter) of livestock to increase gradually with age from starting ranges for neonates of 50 to 80 for calves and sheep and 70 to 90 for foals and pigs. Expected or "normal" values for the adults are in the ranges of 70 to 100 for cattle, 120 to 150 for sheep, 130 to 160 for horses, and 180 to 220 for swine. Normal liver Se concentrations are considered to range between 1.2 and 2.0 micrograms/g on a dry weight basis, regardless of the species or age. Based on samples submitted to MSU-AHDL between September 1990 and August 1991, contemporary feeding practices in the Michigan area resulted in mean serum Se values (nanograms per milliliter) of 75 +/- 19 for adult Holsteins, 170 +/- 27 for adult swine (mixed breeds), and 137 +/- 30 for adult race horses. Within that period of time, two field cases of Se toxicity were diagnosed. One involved feeder pigs with a recorded high serum Se value of 1,525 ng/mL due to a commercial premix manufacturing error.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. Jumping to New Heights: Horsemanship Activities. Level 5. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08057

    ERIC Educational Resources Information Center

    Neiberger-Miller, Ami

    2004-01-01

    This is the fifth in a series of five horse project activity guides for youth. Levels 1-3 focus on "horse-less" activities, while Levels 4 and 5 zero in on riding and horsemanship. Each guide has an achievement program to encourage youth to learn and develop life skills. The assistance of a horse project helper in completing the achievement…

  18. Riding the Range: Horse Riding Activities. Level 4. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08056

    ERIC Educational Resources Information Center

    Neiberger-Miller, Ami

    2004-01-01

    This is the fourth in a series of five horse project activity guides for youth. Levels 1-3 focus on "horse-less" activities, while Levels 4 and 5 zero in on riding and horsemanship. Each guide has an achievement program to encourage youth to learn and develop life skills. The assistance of a horse project helper in completing the achievement…

  19. Head, Heart, & Hooves: Horse Raising Activities. Level 2. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08054

    ERIC Educational Resources Information Center

    Neiberger-Miller, Ami

    2004-01-01

    This is the second in a series of five horse project activity guides for youth. Levels 1-3 focus on "horse-less" activities, while Levels 4 and 5 zero in on riding and horsemanship. Each guide has an achievement program to encourage youth to learn and develop life skills. The assistance of a horse project helper in completing the achievement…

  20. Building bridges using livestock as ecosystem engineers in semi-arid rangelands: Addressing conservation and livestock production goals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic livestock have the potential to function as ecosystem engineers in semi-arid rangelands, but their utility has been compromised by management practices that emphasize livestock production, homogeneous use of vegetation and removal/control of interacting disturbances of fire and prairie dogs...

  1. 25 CFR 166.309 - Who determines livestock class and livestock ownership requirements on permitted Indian land?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Who determines livestock class and livestock ownership requirements on permitted Indian land? 166.309 Section 166.309 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAND AND WATER GRAZING PERMITS Land and Operations Management § 166.309 Who...

  2. A new model for in situ nitrogen incorporation into 4H-SiC during epitaxy

    PubMed Central

    Ferro, Gabriel; Chaussende, Didier

    2017-01-01

    Nitrogen doping of 4H-SiC during vapor phase epitaxy is still lacking of a general model explaining the apparently contradictory trends obtained by different teams. In this paper, the evolutions of nitrogen incorporation (on both polar Si and C faces) as a function of the main growth parameters (C/Si ratio, temperature, pressure and growth rate) are reviewed and explained using a model based on surface exchanges between the gas phase and the uppermost 4H-SiC atomic layers. In this model, N incorporation is driven mainly by the transient formation of C vacancies, due to H2 etching, at the surface or near the surface. It is shown that all the growth parameters are influencing the probability of C vacancies formation in a similar manner as they do for N incorporation. The surface exchange model proposes a new framework for explaining the experimental results even beyond the commonly accepted reactor type dependency. PMID:28211528

  3. Nanocrystalline diamond films as UV-semitransparent Schottky contacts to 4H-SiC

    NASA Astrophysics Data System (ADS)

    Tadjer, Marko J.; Hobart, Karl D.; Caldwell, Joshua D.; Butler, James E.; Liu, Kendrick X.; Eddy, Charles R.; Gaskill, D. Kurt; Lew, K. K.; VanMil, Brenda L.; Myers-Ward, Rachael L.; Ancona, Mario G.; Kub, Fritz J.; Feygelson, Tatyana I.

    2007-10-01

    A heterojunction between thin films of nanocrystalline diamond (NCD) and 4H-SiC has been developed. Undoped and B-doped NCDs were deposited on both n- and p- SiC epilayers. I-V measurements on p + NCD /n- SiC indicated Schottky rectifying behavior with a turn-on voltage of around 0.2V. The current increased over eight orders of magnitude with an ideality factor of 1.17 at 30°C. Ideal energy-band diagrams suggested a possible conduction mechanism for electron transport from the SiC conduction band to either the valence band or acceptor level of the NCD film. Applications as an UV semitransparent electrical contact to 4H-SiC are discussed.

  4. A 4H Silicon Carbide Gate Buffer for Integrated Power Systems

    SciTech Connect

    Ericson, N; Frank, S; Britton, C; Marlino, L; Ryu, SH; Grider, D; Mantooth, A; Francis, M; Lamichhane, R; Mudholkar, M; Shepherd, P; Glover, M; Valle-Mayorga, J; McNutt, T; Barkley, A; Whitaker, B; Cole, Z; Passmore, B; Lostetter, A

    2014-02-01

    A gate buffer fabricated in a 2-mu m 4H silicon carbide (SiC) process is presented. The circuit is composed of an input buffer stage with a push-pull output stage, and is fabricated using enhancement mode N-channel FETs in a process optimized for SiC power switching devices. Simulation and measurement results of the fabricated gate buffer are presented and compared for operation at various voltage supply levels, with a capacitive load of 2 nF. Details of the design including layout specifics, simulation results, and directions for future improvement of this buffer are presented. In addition, plans for its incorporation into an isolated high-side/low-side gate-driver architecture, fully integrated with power switching devices in a SiC process, are briefly discussed. This letter represents the first reported MOSFET-based gate buffer fabricated in 4H SiC.

  5. Thermodynamic calculations in the system CH4-H2O and methane hydrate phase equilibria.

    PubMed

    Circone, Susan; Kirby, Stephen H; Stern, Laura A

    2006-04-27

    Using the Gibbs function of reaction, equilibrium pressure, temperature conditions for the formation of methane clathrate hydrate have been calculated from the thermodynamic properties of phases in the system CH4-H2O. The thermodynamic model accurately reproduces the published phase-equilibria data to within +/-2 K of the observed equilibrium boundaries in the range 0.08-117 MPa and 190-307 K. The model also provides an estimate of the third-law entropy of methane hydrate at 273.15 K, 0.1 MPa of 56.2 J mol(-1) K(-1) for 1/nCH4.H2O, where n is the hydrate number. Agreement between the calculated and published phase-equilibria data is optimized when the hydrate composition is fixed and independent of the pressure and temperature for the conditions modeled.

  6. A new model for in situ nitrogen incorporation into 4H-SiC during epitaxy

    NASA Astrophysics Data System (ADS)

    Ferro, Gabriel; Chaussende, Didier

    2017-02-01

    Nitrogen doping of 4H-SiC during vapor phase epitaxy is still lacking of a general model explaining the apparently contradictory trends obtained by different teams. In this paper, the evolutions of nitrogen incorporation (on both polar Si and C faces) as a function of the main growth parameters (C/Si ratio, temperature, pressure and growth rate) are reviewed and explained using a model based on surface exchanges between the gas phase and the uppermost 4H-SiC atomic layers. In this model, N incorporation is driven mainly by the transient formation of C vacancies, due to H2 etching, at the surface or near the surface. It is shown that all the growth parameters are influencing the probability of C vacancies formation in a similar manner as they do for N incorporation. The surface exchange model proposes a new framework for explaining the experimental results even beyond the commonly accepted reactor type dependency.

  7. Thermodynamic calculations in the system CH4-H2O and methane hydrate phase equilibria

    USGS Publications Warehouse

    Circone, S.; Kirby, S.H.; Stern, L.A.

    2006-01-01

    Using the Gibbs function of reaction, equilibrium pressure, temperature conditions for the formation of methane clathrate hydrate have been calculated from the thermodynamic properties of phases in the system CH4-H 2O. The thermodynamic model accurately reproduces the published phase-equilibria data to within ??2 K of the observed equilibrium boundaries in the range 0.08-117 MPa and 190-307 K. The model also provides an estimate of the third-law entropy of methane hydrate at 273.15 K, 0.1 MPa of 56.2 J mol-1 K-1 for 1/n CH4??H 2O, where n is the hydrate number. Agreement between the calculated and published phase-equilibria data is optimized when the hydrate composition is fixed and independent of the pressure and temperature for the conditions modeled. ?? 2006 American Chemical Society.

  8. Monte Carlo Simulation of Electron Transport in 4H- and 6H-SiC

    SciTech Connect

    Sun, C. C.; You, A. H.; Wong, E. K.

    2010-07-07

    The Monte Carlo (MC) simulation of electron transport properties at high electric field region in 4H- and 6H-SiC are presented. This MC model includes two non-parabolic conduction bands. Based on the material parameters, the electron scattering rates included polar optical phonon scattering, optical phonon scattering and acoustic phonon scattering are evaluated. The electron drift velocity, energy and free flight time are simulated as a function of applied electric field at an impurity concentration of 1x10{sup 18} cm{sup 3} in room temperature. The simulated drift velocity with electric field dependencies is in a good agreement with experimental results found in literature. The saturation velocities for both polytypes are close, but the scattering rates are much more pronounced for 6H-SiC. Our simulation model clearly shows complete electron transport properties in 4H- and 6H-SiC.

  9. Characteristics and analysis of 4H-SiC PiN diodes with a carbon-implanted drift layer

    NASA Astrophysics Data System (ADS)

    Jiangmei, Feng; Huajun, Shen; Xiaohua, Ma; Yun, Bai; Jia, Wu; Chengzhan, Li; Kean, Liu; Xinyu, Liu

    2016-04-01

    The characteristics of 4H-SiC PiN diodes with a carbon-implanted drift layer was investigated and the reason of characteristics improvement was analyzed. The forward voltage drops of the diodes with carbon-implanted drift layer were around 3.3 V, which is lower than that of devices without carbon implantation, the specific-on resistance was decreased from 9.35 to 4.38 mΩ·cm2 at 100 A/cm2, and the reverse leakage current was also decreased. The influence of carbon incorporation in the SiC crystalline grids was studied by using deep-level transient spectroscopy (DLTS). The DLTS spectra revealed that the Z 1/2 traps, which were regarded as the main lifetime limiting defects, were dramatically reduced. It is proposed that the reduction of Z 1/2 traps can achieve longer carrier lifetime in the drift layer, which is beneficial to the performance of bipolar devices. Project supported by the Opening Project of Key Laboratory of Microelectronics Devices & Integrated Technology, Institute of Microelectronics, Chinese Academy of Sciences.

  10. 4H-silicon carbide-dielectric interface recombination analysis using free carrier absorption

    NASA Astrophysics Data System (ADS)

    Suvanam, S. S.; Gulbinas, K.; Usman, M.; Linnarson, M. K.; Martin, D. M.; Linnros, J.; Grivickas, V.; Hallén, A.

    2015-03-01

    In this paper, an alternative method to characterize the interface between 4H polytype of Silicon Carbide (4H-SiC) and passivating dielectric layers is established. The studies are made on dielectric-semiconductor test structures using Al2O3 as dielectric on 4H-SiC n-type epitaxial layers. Samples with different pre- and post-dielectric deposition preparations have been fabricated on epilayers of varying thicknesses. Effective lifetimes (τeff) of all the samples were measured by an optical pump-probe method utilizing free carrier absorption (FCA) to analyse the influence of the 4H-SiC/dielectric interface on charge carrier recombination. The relative contribution to τeff from the surfaces increases with decreasing epilayer thickness, and by analysing the data in combination with numerical modelling, it is possible to extract values of the surface recombination velocities (SRVs) for interfaces prepared in different ways. For instance, it is found that SRV for a standard cleaning procedure is 2 × 106 cm/s compared to a more elaborate RCA process, yielding a more than 50 times lower value of 3.5 × 104 cm/s. Furthermore, the density of interface traps (Dit) is extracted from capacitance-voltage (CV) measurements using the Terman method and a comparison is made between the SRV extracted from FCA measurements and Dits extracted from CV measurements on the same structures fabricated with metal contacts. It is observed that the SRV increase scales linearly with the increase in Dit. The strong qualitative correlation between FCA and CV data shows that FCA is a useful characterization technique, which can also yield more quantitative information about the charge carrier dynamics at the interface.

  11. 4-[4-(Diethyl-amino)benzyl-ideneamino]-4H-1,2,4-triazole.

    PubMed

    Pan, Jian Xin; Zhang, Ju Zhou; Chen, Qian Wang

    2008-05-03

    The title compound, C(13)H(17)N(5), is a Schiff base synthesized by the reaction of 4-amino-4H-1,2,4-triazole and 4-(diethyl-amino)benzaldehyde. The triazole ring forms a dihedral angle of 5.77 (16)° with the benzene ring. The crystal structure is stabilized by an inter-molecular C-H⋯N hydrogen bond.

  12. I-V characteristics simulation of silicon carbide Ti/4H-SiC Schottky diode

    NASA Astrophysics Data System (ADS)

    Panchenko, P.; Rybalka, S.; Malakhanov, A.; Krayushkina, E.; Radkov, A.

    2016-12-01

    The simulation of current-voltage characteristics for 4H-SiC Schottky diode with Ti Schottky contact has been carried out with used of TCAD program. Obtained current-voltage characteristics has been analyzed and compared with theoretical and experimental results. It is established that the Schottky diode parameters (forward current, ideality coefficient, Schottky barrier height, breakdown voltage) obtained in proposed model are good agreement with data for such type diodes.

  13. High Resolution Topography Analysis on Threading Edge Dislocations in 4H-SiC Epilayers

    SciTech Connect

    Kamata, I.; Nagano, M; Tsuchida, H; Chen, Y; Dudley, M

    2009-01-01

    Threading edge dislocations (TEDs) in a 4H-SiC epitaxial layer are investigated using high-resolution synchrotron topography. Six types of TED image are confirmed to correspond to the Burgers vector directions by a comparison of computer simulated images and observed topography images in crystal boundaries. Using a mapping method, a wide spatial distribution of the six types of TED is examined in a quarter section of a 2-inch wafer.

  14. Resistance of 4H-SiC Schottky barriers at high forward-current densities

    SciTech Connect

    Ivanov, P. A. Samsonova, T. P.; Il’inskaya, N. D.; Serebrennikova, O. Yu.; Kon’kov, O. I.; Potapov, A. S.

    2015-07-15

    The resistance of Schottky barriers based on 4H-SiC is experimentally determined at high forward-current densities. The measured resistance is found to be significantly higher than the resistance predicted by classical mechanisms of electron transport in Schottky contacts. An assumption concerning the crucial contribution of the tunnel-transparent intermediate oxide layer between the metal and semiconductor to the barrier resistance is proposed and partially justified.

  15. Greenhouse gas mitigation potentials in the livestock sector

    NASA Astrophysics Data System (ADS)

    Herrero, Mario; Henderson, Benjamin; Havlík, Petr; Thornton, Philip K.; Conant, Richard T.; Smith, Pete; Wirsenius, Stefan; Hristov, Alexander N.; Gerber, Pierre; Gill, Margaret; Butterbach-Bahl, Klaus; Valin, Hugo; Garnett, Tara; Stehfest, Elke

    2016-05-01

    The livestock sector supports about 1.3 billion producers and retailers, and contributes 40-50% of agricultural GDP. We estimated that between 1995 and 2005, the livestock sector was responsible for greenhouse gas emissions of 5.6-7.5 GtCO2e yr-1. Livestock accounts for up to half of the technical mitigation potential of the agriculture, forestry and land-use sectors, through management options that sustainably intensify livestock production, promote carbon sequestration in rangelands and reduce emissions from manures, and through reductions in the demand for livestock products. The economic potential of these management alternatives is less than 10% of what is technically possible because of adoption constraints, costs and numerous trade-offs. The mitigation potential of reductions in livestock product consumption is large, but their economic potential is unknown at present. More research and investment are needed to increase the affordability and adoption of mitigation practices, to moderate consumption of livestock products where appropriate, and to avoid negative impacts on livelihoods, economic activities and the environment.

  16. Links between livestock production, the environment and sustainable development.

    PubMed

    Pradbre, J-P

    2014-12-01

    This study examines the prospects for strong growth in the supply and demand for animal products worldwide, especially in developing countries, where 80% of the world's population lives. Based on scientific publications, statistics and field observations, it reviews greenhouse gas emission levels from livestock, the ability of ruminant livestock systems to sequester carbon and the capacity of the livestock industry to meet the challenge of sustainable development and to share its benefits while minimising impacts to climate change. Special attention is paid to the situation of the 800 million livestock farmers in the world living at the extreme end of poverty. The study underlines the importance of improving livestock productivity and the interdependence of the economic, environmental and social components of sustainable development. It highlights how, in the least developed countries and most lower-middle-income countries, the pressure exerted by animal diseases hampers efforts to improve livestock productivity. Poor livestock farmers have not sufficiently benefited from development policies and need support to adopt technological advances to meet the challenges of sustainable development and poverty reduction.

  17. Photophysics of a ruthenium 4H-imidazole panchromatic dye in interaction with titanium dioxide.

    PubMed

    Schindler, Julian; Kupfer, Stephan; Wächtler, Maria; Guthmuller, Julien; Rau, Sven; Dietzek, Benjamin

    2015-04-07

    The photophysics of bis(4,4'-di-tert-butyl-2,2'-bipyridine-κ(2)N,N')[2-(4-carboxyphenyl)-4,5-bis(p-tolylimino-κN)imidazolato]ruthenium(II) hexafluorophosphate is investigated, both in solution and attached to a nanocrystalline TiO2 film. The studied substitution pattern of the 4H-imidazole ligand is observed to block a photoinduced structural reorganization pathway within the 4H-imidazole ligand that has been previously investigated. Protonation at the 4H-imidazole ring decreases the excited-state lifetime in solution. When the unprotonated dye is anchored to TiO2, photoinduced electron injection occurs from thermally nonrelaxed triplet metal-to-ligand charge transfer ((3)MLCT) states with a characteristic time constant of 0.5 ps and an injection efficiency of roughly 25%. Electron injection from the subsequently populated thermalized (3)MLCT state of the dye does not take place. The energy of this state seems to be lower than the conduction band edge of TiO2.

  18. Laboratory detection of the C3N an C4H free radicals

    NASA Technical Reports Server (NTRS)

    Gottlieb, C. A.; Gottlieb, E. W.; Thaddeus, P.; Kawamura, H.

    1983-01-01

    The millimeter-wave spectra of the linear carbon chain free radicals C3N and C4H, first identified in IRC + 10216 and hitherto observed only in a few astronomical sources, have been detected with a Zeeman-modulated spectrometer in laboratory glow discharges through low pressure flowing mixtures of N2 + HC3N and He + HCCH, respectively. Four successive rotational transitions between 168 and 198 GHz have been measured for C3N, and five rotational transitions between 143 and 200 GHz for C4H; each is a well-resolved spin doublet owing to the unpaired electron present in both species. Precise values for the rotational, centrifugal distortion, and spin doubling constants have been obtained, which, with hyperfine constants derived from observations of the lower rotational transitions in the astronomical source TMC 1, allow all the rotational transitions of C3N and C4H at frequencies less than 300 GHz to be calculated to an absolute accuracy exceeding 1 ppm.

  19. Combustion of CH4/H2/air mixtures in catalytic microreactors.

    PubMed

    Specchia, Stefania; Vella, Luigi D; Burelli, Sara; Saracco, Guido; Specchia, Vito

    2009-03-23

    The combustion of CH(4)/H(2)/HC mixtures in a very small space represents an alternative, innovative way to produce thermal/electrical energy. Pd/NiCrO(4) catalysts are lined on SiC monoliths via in situ solution combustion synthesis (SCS), and the monoliths are then tested by feeding CH(4), H(2), and lean CH(4)/H(2) mixtures into a lab-scale test rig at an output thermal power of 7.6 MW(th) m(-3). In all cases, the combustion temperature shifts to values lower than those observed in non-catalytic combustion. When the power density is kept constant (by adding H(2) to the gas mixture), the value of CH(4)-T(50) (the half-conversion temperature of CH(4)) decreases relative to that of pure CH(4), and the slope of the conversion curve becomes steeper. The higher the H(2) concentration is, the higher the reactivity of the mixture towards CH(4) oxidation-probably due to a higher production of H(2) reactive radicals (OH).

  20. Computational Study of Anisotropic Epitaxial Recrystallization in 4H-SiC

    SciTech Connect

    Gao, Fei; Zhang, Yanwen; Posselt, Matthias; Weber, William J.

    2008-03-26

    Two nano-sized amorphous layers were employed within a crystalline cell to study anisotropic expitaxial recrystallization using molecular dynamics (MD) methods in 4H-SiC. Both amorphous layers were created with the normal of the amorphous-crystalline (a-c) interfaces along the [0001] direction, but one with a microscopic extension long the [0001] direction, i.e. the dimension along the [-12-10] direction is much larger than that along the [-12-10] direction (Ix model), and another with a microscopic extension long the [-1010] direction (Iy model). The amorphous layer within the Ix model can be completely recrystallized at 2000 K within achievable simulation time, and the recrystallization is driven by a step-regrowth mechanism. On the other hand, the nucleation and growth of secondary ordered phases are observed at high temperatures in the Iy model. The temperature for recrystallization of the amorphous layer into high quality 4H-SiC is estimated to be below 1500 K. As compared with other models, it is found that the regrowth rates and recrystallization mechanisms strongly depend on the orientation of 4H-SiC, whereas the activation energy spectra for recrystallization processes are independent on a specific polytypic structure, with activation energies ranging from 0.8 to 1.7 eV.

  1. Demonstration of the First 4H-SiC EUV Detector with Large Detection Area

    NASA Technical Reports Server (NTRS)

    Xin, Xiaobin; Yan, Feng; Koeth, Timothy W.; Hu, Jun; Zhao, Jian H.

    2005-01-01

    Ultraviolet (UV) and Extreme Ultraviolet (EUV) detectors are very attractive in astronomy, photolithography and biochemical applications. For EUV applications, most of the semiconductor detectors based on PN or PIN structures suffer from the very short penetration depth. Most of the carries are absorbed at the surface and recombined there due to the high surface recombination before reach the depletion region, resulting very low quantum efficiency. On the other hand, for Schottky structures, the active region starts from the surface and carriers generated from the surface can be efficiently collected. 4H-Sic has a bandgap of 3.26eV and is immune to visible light background noise. Also, 4H-Sic detectors usually have very good radiation hardness and very low noise, which is very important for space applications where the signal is very weak. The E W photodiodes presented in this paper are based on Schottky structures. Platinum (Pt) and Nickel (Ni) are selected as the Schottky contact metals, which have the highest electron work functions (5.65eV and 5.15eV, respectively) among all the known metals on 4H-Sic.

  2. Incipient plasticity in 4H-SiC during quasistatic nanoindentation.

    PubMed

    Goel, Saurav; Yan, Jiwang; Luo, Xichun; Agrawal, Anupam

    2014-06-01

    Silicon carbide (SiC) is an important orthopedic material due to its inert nature and superior mechanical and tribological properties. Some of the potential applications of silicon carbide include coating for stents to enhance hemocompatibility, coating for prosthetic-bearing surfaces and uncemented joint prosthetics. This study is the first to explore nanomechanical response of single crystal 4H-SiC through quasistatic nanoindentation. Displacement controlled quasistatic nanoindentation experiments were performed on a single crystal 4H-SiC specimen using a blunt Berkovich indenter (300nm tip radius) at extremely fine indentation depths of 5nm, 10nm, 12nm, 25nm, 30nm and 50nm. Load-displacement curve obtained from the indentation experiments showed yielding or incipient plasticity in 4H-SiC typically at a shear stress of about 21GPa (~an indentation depth of 33.8nm) through a pop-in event. An interesting observation was that the residual depth of indent showed three distinct patterns: (i) positive depth hysteresis above 33nm, (ii) no depth hysteresis at 12nm, and (iii) negative depth hysteresis below 12nm. This contrasting depth hysteresis phenomenon is hypothesized to originate due to the existence of compressive residual stresses (upto 143MPa) induced in the specimen by the polishing process prior to the nanoindentation.

  3. Water requirements for livestock production: a global perspective.

    PubMed

    Schlink, A C; Nguyen, M L; Viljoen, G J

    2010-12-01

    Water is a vital but poorly studied component of livestock production. It is estimated that livestock industries consume 8% of the global water supply, with most of that water being used for intensive, feed-based production. This study takes a broad perspective of livestock production as a component of the human food chain, and considers the efficiency of its water use. Global models are in the early stages of development and do not distinguish between developing and developed countries, or the production systems within them. However, preliminary indications are that, when protein production is adjusted for biological value in the human diet, no plant protein is significantly more efficient at using water than protein produced from eggs, and only soybean is more water efficient than milk and goat and chicken meat. In some regions, especially developing countries, animals are not used solely for food production but also provide draught power, fibre and fertiliser for crops. In addition, animals make use of crop by-products that would otherwise go to waste. The livestock sector is the fastest-growing agricultural sector, which has led to increasing industrialisation and, in some cases, reduced environmental constraints. In emerging economies, increasing involvement in livestock is related to improving rural wealth and increasing consumption of animal protein. Water usage for livestock production should be considered an integral part of agricultural water resource management, taking into account the type of production system (e.g. grain-fed or mixed crop-livestock) and scale (intensive or extensive), the species and breeds of livestock, and the social and cultural aspects of livestock farming in various countries.

  4. Nitrogen incorporation and interface trap reduction in silicon dioxide/4H-silicon carbide

    NASA Astrophysics Data System (ADS)

    McDonald, Kyle

    2001-07-01

    Silicon carbide is a wide band gap semiconductor whose properties make it an ideal material for high power applications. Silicon carbide thermally oxidizes to form SiO2, which is used as a gate insulator in MOSFETs; however, MOSFETs produced from the 4H-SiC polytype exhibit much lower channel mobilities than expected. A large density of interface traps produced by carbon clusters and located near the conduction band has been proposed as the source of the poor mobility. The nitridation of the SiO2/4H-SiC interface using NO and NH3 has been shown to reduce this interface trap density and improve the channel mobility. In this work, the kinetics of nitrogen incorporation using NO and NH3 are compared, and the relationship between nitrogen content and interface trap density are discussed. The nitridation of SiO2/4H-SiC in NO at temperatures from 1050--1175°C incorporates ˜1014 cm-2 of nitrogen at the interface. Oxygen formed during the thermal decomposition of NO oxidizes the substrate and removes carbon and nitrogen from the interface. When the nitridation and oxidation reactions reach equilibrium, the nitrogen content saturates independently of temperature. The nitridation of SiO 2/4H-SiC in NH; at temperatures from 1050--1175°C incorporates ˜10 16 cm-2 uniformly throughout the oxide bulk. During nitridation, oxygen is removed from the oxide, and the stoichiometry of the film is changed significantly. The nitridation of SiO2/4H-SiC in NO reduces the interface trap density near the conduction band by a factor of 10, but the trap density remains high. The complete passivation of these particular traps occurs at a nitrogen content of ≈2.5 x 1014 cm-2 , regardless of the annealing conditions. The data are consistent with a model of the interface in which the traps near the conduction band are produced by large carbon clusters with a near-continuum of energy levels. The passivation of these traps with nitrogen then proceeds by the dissolution of these carbon clusters

  5. Viral diagnosis in Indian livestock using customized microarray chips

    PubMed Central

    Yadav, Brijesh S; Pokhriyal, Mayank; Ratta, Barkha; Kumar, Ajay; Saxena, Meeta; Sharma, Bhaskar

    2015-01-01

    Viral diagnosis in Indian livestock using customized microarray chips is gaining momentum in recent years. Hence, it is possible to design customized microarray chip for viruses infecting livestock in India. Customized microarray chips identified Bovine herpes virus-1 (BHV-1), Canine Adeno Virus-1 (CAV-1), and Canine Parvo Virus-2 (CPV-2) in clinical samples. Microarray identified specific probes were further confirmed using RT-PCR in all clinical and known samples. Therefore, the application of microarray chips during viral disease outbreaks in Indian livestock is possible where conventional methods are unsuitable. It should be noted that customized application requires a detailed cost efficiency calculation. PMID:26912948

  6. Viral diagnosis in Indian livestock using customized microarray chips.

    PubMed

    Yadav, Brijesh S; Pokhriyal, Mayank; Ratta, Barkha; Kumar, Ajay; Saxena, Meeta; Sharma, Bhaskar

    2015-01-01

    Viral diagnosis in Indian livestock using customized microarray chips is gaining momentum in recent years. Hence, it is possible to design customized microarray chip for viruses infecting livestock in India. Customized microarray chips identified Bovine herpes virus-1 (BHV-1), Canine Adeno Virus-1 (CAV-1), and Canine Parvo Virus-2 (CPV-2) in clinical samples. Microarray identified specific probes were further confirmed using RT-PCR in all clinical and known samples. Therefore, the application of microarray chips during viral disease outbreaks in Indian livestock is possible where conventional methods are unsuitable. It should be noted that customized application requires a detailed cost efficiency calculation.

  7. Livestock Helminths in a Changing Climate: Approaches and Restrictions to Meaningful Predictions.

    PubMed

    Fox, Naomi J; Marion, Glenn; Davidson, Ross S; White, Piran C L; Hutchings, Michael R

    2012-03-06

    Climate change is a driving force for livestock parasite risk. This is especially true for helminths including the nematodes Haemonchus contortus, Teladorsagia circumcincta, Nematodirus battus, and the trematode Fasciola hepatica, since survival and development of free-living stages is chiefly affected by temperature and moisture. The paucity of long term predictions of helminth risk under climate change has driven us to explore optimal modelling approaches and identify current bottlenecks to generating meaningful predictions. We classify approaches as correlative or mechanistic, exploring their strengths and limitations. Climate is one aspect of a complex system and, at the farm level, husbandry has a dominant influence on helminth transmission. Continuing environmental change will necessitate the adoption of mitigation and adaptation strategies in husbandry. Long term predictive models need to have the architecture to incorporate these changes. Ultimately, an optimal modelling approach is likely to combine mechanistic processes and physiological thresholds with correlative bioclimatic modelling, incorporating changes in livestock husbandry and disease control. Irrespective of approach, the principal limitation to parasite predictions is the availability of active surveillance data and empirical data on physiological responses to climate variables. By combining improved empirical data and refined models with a broad view of the livestock system, robust projections of helminth risk can be developed.

  8. Anaerobic digestion of livestock manures in the USA: A current opportunities casebook

    SciTech Connect

    Lusk, P.D.

    1994-12-31

    Growth and concentration of the livestock industry creates opportunities for the proper disposal of the large quantities of manures generated at dairy, swine and poultry farms. One manure management system provides not only pollution prevention but also converts a manure management problem into a new profit center. Economic evaluations and case studies of operating systems indicate that the anaerobic digestion of livestock manures is a commercially-available bioconversion technology with considerable potential for providing profitable co-products including a cost-effective alternative fuel for livestock production operations. This Casebook examines some of the current opportunities for the recovery of methane from the anaerobic digestion of animal manures. An introduction to the engineering economies of these technologies is provided and possible end-use applications for methane gas generated by the digestion process are discussed. The economic evaluations are based on engineering studies of digesters that generate electricity from the recovered methane. Regression models, which can be used to estimate digester cost and internal rate of return, are developed from the evaluations. Case studies of operating digesters, including project and maintenance histories, and the operator`s {open_quotes}lessons learned{close_quotes}, are provided as a reality check.

  9. A theoretical study on the reaction mechanism of O2 with C4H9• radical.

    PubMed

    Du, Hong-chen; Gong, Xue-dong

    2012-05-01

    Ab initio calculations have been performed using the complete basis set model (CBS-QB3) to study the reaction mechanism of butane radical (C(4)H(9)•) with oxygen (O(2)). On the calculated potential energy surface, the addition of O(2) to C(4)H(9)• forms three intermediates barrierlessly, which can undergo subsequent isomerization or decomposition reaction leading to various products: HOO• + C(4)H(8), C(2)H(5)• + CH(2)CHOOH, OH• + C(3)H(7)CHO, OH• + cycle-C(4)H(8)O, CH(3)• + CH(3)CHCHOOH, CH(2)OOH• + C(3)H(6). Five pathways are supposed in this study. After taking into account the reaction barrier and enthalpy, the most possible reaction pathway is C(4)H(9)• + O(2) → IM1 → TS5 → IM3 → TS6 → IM4 → TS7 → OH• + cycle-C(4)H(8)O.

  10. Cryptosporidium parvum Infection Following Contact with Livestock

    PubMed Central

    Suler, Denis; Mullins, David; Rudge, Travis; Ashurst, John

    2016-01-01

    Context: Scours, or calf diarrhea, is an infectious gastrointestinal disease commonly found in the calves of dairy farms. It primarily presents with diarrhea that can be life threatening to the animal and is also contagious and threatening to the other livestock. Cryptosporidium is one of the major causes of scours and can be transmitted to humans via fecal-oral route, resulting in diarrheal illnesses. Cryptosporidiosis infection usually occurs as a waterborne outbreak with the potential to affect many people at once. Case Report: We report a case of a 24-year-old female farmer who presented to the emergency department with diarrhea after taking care of ill cattle with similar symptoms. Fecal cultures were positive for Cryptosporidium parvum. Given the patient was immunocompetent, no further treatment was warranted. Conclusion: Confirmed cases should be reported, however, treatment is only recommended in children and immunocompromised adults. Clinicians should educate patients on the importance of proper hygiene and handling techniques in order to decrease transmission and recurrence of the protozoan infection. PMID:27583243

  11. The anterior pituitary gland: lessons from livestock.

    PubMed

    Scanes, C G; Jeftinija, S; Glavaski-Joksimovic, A; Proudman, J; Arámburo, C; Anderson, L L

    2005-07-01

    There has been extensive research of the anterior pituitary gland of livestock and poultry due to the economic (agricultural) importance of physiological processes controlled by it including reproduction, growth, lactation and stress. Moreover, farm animals can be biomedical models or useful in evolutionary/ecological research. There are for multiple sites of control of the secretion of anterior pituitary hormones. These include the potential for independent control of proliferation, differentiation, de-differentiation and/or inter-conversion cell death, expression and translation, post-translational modification (potentially generating multiple isoforms with potentially different biological activities), release with or without a specific binding protein and intra-cellular catabolism (proteolysis) of pituitary hormones. Multiple hypothalamic hypophysiotropic peptides (which may also be produced peripherally, e.g. ghrelin) influence the secretion of the anterior pituitary hormones. There is also feedback for hormones from the target endocrine glands. These control mechanisms show broadly a consistency across species and life stages; however, there are some marked differences. Examples from growth hormone, prolactin, follicle stimulating hormone and luteinizing hormone will be considered. In addition, attention will be focused on areas that have been neglected including the role of stellate cells, multiple sub-types of the major adenohypophyseal cells, functional zonation within the anterior pituitary and the role of multiple secretagogues for single hormones.

  12. Livestock rabies outbreaks in Shanxi province, China.

    PubMed

    Feng, Ye; Shi, Yanyan; Yu, Mingyang; Xu, Weidi; Gong, Wenjie; Tu, Zhongzhong; Ding, Laixi; He, Biao; Guo, Huancheng; Tu, Changchun

    2016-10-01

    Dogs play an important role in rabies transmission throughout the world. In addition to the severe human rabies situation in China, spillover of rabies virus from dogs in recent years has caused rabies outbreaks in sheep, cattle and pigs, showing that there is an increasing threat to other domestic animals. Two livestock rabies outbreaks were caused by dogs in Shanxi province, China from April to October in 2015, resulting in the deaths of 60 sheep, 10 cattle and one donkey. Brain samples from one infected bovine and the donkey were determined to be rabies virus (RABV) positive by fluorescent antibody test (FAT) and reverse transcription polymerase chain reaction (RT-PCR). The complete RABV N genes of the two field strains, together with those of two previously confirmed Shanxi dog strains, were amplified, sequenced and compared phylogenetically with published sequences of the N gene of RABV strains from Shanxi and surrounding provinces. All of the strains from Shanxi province grouped closely, sharing 99.6 %-100 % sequence identity, indicating the wide distribution and transmission of dog-mediated rabies in these areas. This is the first description of donkey rabies symptoms with phylogenetic analysis of RABVs in Shanxi province and surrounding regions. The result emphasizes the need for mandatory dog rabies vaccination and improved public education to eradicate dog rabies transmission.

  13. Livestock Waste Management in a Quality Environment. Circular 1074.

    ERIC Educational Resources Information Center

    Jedele, D. G., Ed.

    This circular provides information to assist in assessing the pollution potential of livestock operations. It discusses a systematic approach to resolving problems through feedlot runoff control, liquid manure handling, hauling and lagooning, and ditching. (CS)

  14. 1. General view of stockyards from livestock exchange building showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. General view of stockyards from livestock exchange building showing (l-r) cattle pens and Buckingham Road, which terminates at "L" Street. View to north. - South Omaha Union Stock Yards, 2900 "O" Plaza, Omaha, Douglas County, NE

  15. 7 CFR 760.209 - Livestock payment calculations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... losses due to wildfires on non-Federal land, will be calculated based on 60 percent of the lesser of: (1...) Payments for an eligible livestock producer for grazing losses due to a wildfire on non-Federal land...

  16. 7 CFR 760.209 - Livestock payment calculations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... losses due to wildfires on non-Federal land, will be calculated based on 60 percent of the lesser of: (1...) Payments for an eligible livestock producer for grazing losses due to a wildfire on non-Federal land...

  17. 7 CFR 760.209 - Livestock payment calculations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... losses due to wildfires on non-Federal land, will be calculated based on 60 percent of the lesser of: (1...) Payments for an eligible livestock producer for grazing losses due to a wildfire on non-Federal land...

  18. 7 CFR 760.209 - Livestock payment calculations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... losses due to wildfires on non-Federal land, will be calculated based on 60 percent of the lesser of: (1...) Payments for an eligible livestock producer for grazing losses due to a wildfire on non-Federal land...

  19. Human anthrax outbreak associated with livestock exposure: Georgia, 2012.

    PubMed

    Navdarashvili, A; Doker, T J; Geleishvili, M; Haberling, D L; Kharod, G A; Rush, T H; Maes, E; Zakhashvili, K; Imnadze, P; Bower, W A; Walke, H T; Shadomy, S V

    2016-01-01

    Human anthrax cases reported in the country of Georgia increased 75% from 2011 (n = 81) to 2012 (n = 142). This increase prompted a case-control investigation using 67 culture- or PCR-confirmed cases and 134 controls matched by residence and gender to investigate risk factor(s) for infection during the month before case onset. Independent predictors most strongly associated with disease in the multivariable modelling were slaughtering animals [odds ratio (OR) 7·3, 95% confidence interval (CI) 2·9-18·1, P 1 km; 15 (12%) of 125 had sick livestock; and 11 (9%) of 128 respondents reported finding dead livestock. We recommend joint public health and veterinary anthrax case investigations to identify areas of increased risk for livestock anthrax outbreaks, annual anthrax vaccination of livestock in those areas, and public awareness education.

  20. Local breeds, livelihoods and livestock keepers' rights in South Asia.

    PubMed

    Köhler-Rollefson, Ilse; Rathore, H S; Mathias, E

    2009-10-01

    In South Asia, and throughout the developing world, the predominant official approach to livestock development has been improvement of production by means of upgrading local breeds via cross-breeding with exotic animals. This strategy has led to the replacement and dilution of locally adapted breeds with non-native ones. This has resulted in an alarming loss that has been estimated by the Food and Agriculture Organization of the United Nations to amount to one breed every two weeks. Based on selected case studies this paper argues that development strategies using locally adapted breeds and species are much more likely to benefit livestock keepers whilst also maintaining domestic animal diversity and bearing a smaller ecological footprint. It also analyses the rationale for "Livestock Keepers' Rights", a principle that grew out of the struggle of traditional livestock keepers to retain control over their production resources, such as grazing areas and breeding stock, in the face of unfavourable policy environments.

  1. 7 CFR 1416.102 - Eligible livestock and producers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) To be considered eligible, livestock must meet all the following conditions: (1) Be adult or non-adult dairy cattle, beef cattle, buffalo, beefalo, equine, poultry, elk, reindeer, sheep, goats,...

  2. 7 CFR 1416.102 - Eligible livestock and producers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...) To be considered eligible, livestock must meet all the following conditions: (1) Be adult or non-adult dairy cattle, beef cattle, buffalo, beefalo, equine, poultry, elk, reindeer, sheep, goats,...

  3. Nutritive value of bamboo as browse for livestock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Small farms in Appalachia need management options that diversify income opportunities; are adaptable to new livestock management strategies; and help maintain environmental integrity. Plantings of temperate bamboo (Poaceae), including species native to West Virginia, were established to determine p...

  4. Ultra-High Voltage 4H-SiC Bi-Directional Insulated Gate Bipolar Transistors

    NASA Astrophysics Data System (ADS)

    Chowdhury, Sauvik

    4H- Silicon Carbide (4H-SiC) is an attractive material for power semiconductor devices due to its large bandgap, high critical electric field and high thermal conductivity compared to Silicon (Si). For ultra-high voltage applications (BV > 10 kV), 4H-SiC Insulated Gate Bipolar Transistors (IGBTs) are favored over unipolar transistors due to lower conduction losses. With improvements in SiC materials and processing technology, promising results have been demonstrated in the area of conventional unidirectional 4H-SiC IGBTs, with breakdown voltage ratings up to 27 kV. This research presents the experimental demonstration of the world's first high voltage bi-directional power transistors in 4H-SiC. Traditionally, four (two IGBTs and two diodes) or two (two reverse blocking IGBTs) semiconductor devices are necessary to yield a bidirectional switch. With a monolithically integrated bidirectional switch as presented here, the number of semiconductor devices is reduced to only one, which results in increased reliability and reduced cost of the overall system. Additionally, by using the unique dual gate operation of BD-IGBTs, switching losses can be reduced to a small fraction of that in conventional IGBTs, resulting in increased efficiency. First, the performance limits of SiC IGBTs are calculated by using analytical methods. The performance benefits of SiC IGBTs over SiC unipolar devices and Si IGBTs are quantified. Numerical simulations are used to optimize the unit cell and edge termination structures for a 15 kV SiC BD-IGBT. The effect of different device parameters on BD-IGBT static and switching performance are quantified. Second, the process technology necessary for the fabrication of high voltage SiC BD-IGBTs is optimized. The effect of different process steps on parameters such as breakdown voltage, carrier lifetime, gate oxide reliability, SiO2-SiC interface charge density is quantified. A carrier lifetime enhancement process has been optimized for lightly doped

  5. Giddy up & Go: Discovering Horses Activities. Level 1. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08053

    ERIC Educational Resources Information Center

    Neiberger-Miller, Ami

    2004-01-01

    This is the first in a series of five horse project activity guides for youth. Levels 1-3 focus on "horse-less" activities, while Levels 4 and 5 zero in on riding and horsemanship. Each guide has an achievement program to encourage youth to learn and develop life skills. This guide focuses on the introductory basics and familiarizes youth with…

  6. Canine Connection: Dog 2--Fun Activities for You and Your Dog. 4-H Skills for Life Animal Series. National 4-H Curriculum. BU-08167

    ERIC Educational Resources Information Center

    National 4-H Council, 2005

    2005-01-01

    Youth explore more about dog health, nutrition, and care, genetic problems, population control, showmanship, training, ethics and budgeting. Youth who engage in this curriculum will develop essential dog project skills such as selecting a dog; investigating breeds; appreciating dogs' places and roles in society; practicing grooming, fitting,…

  7. Carnivore-caused livestock mortality in Trans-Himalaya.

    PubMed

    Namgail, Tsewang; Fox, Joseph L; Bhatnagar, Yash Veer

    2007-04-01

    The loss of livestock to wild predators is an important livelihood concern among Trans-Himalayan pastoralists. Because of the remoteness and inaccessibility of the region, few studies have been carried out to quantify livestock depredation by wild predators. In the present study, we assessed the intensity of livestock depredation by snow leopard Uncia uncia, Tibetan wolf Canis lupus chanku, and Eurasian lynx Lynx l. isabellina in three villages, namely Gya, Rumtse, and Sasoma, within the proposed Gya-Miru Wildlife Sanctuary in Ladakh, India. The three villages reported losses of 295 animals to these carnivores during a period of 2.5 years ending in early 2003, which represents an annual loss rate of 2.9% of their livestock holdings. The Tibetan wolf was the most important predator, accounting for 60% of the total livestock loss because of predation, followed by snow leopard (38%) and lynx (2%). Domestic goat was the major victim (32%), followed by sheep (30%), yak (15%), and horse (13%). Wolves killed horses significantly more and goats less than would be expected from their relative abundance. Snow leopards also killed horses significantly more than expected, whereas they killed other livestock types in proportion to their abundance. The three villages combined incurred an estimated annual monetary loss of approximately $USD 12,120 amounting to approximately $USD 190/household/y. This relatively high total annual loss occurred primarily because of depredation of the most valuable livestock types such as yak and horse. Conservation actions should initially attempt to target decrease of predation on these large and valuable livestock species.

  8. 4H-SiC JFET Multilayer Integrated Circuit Technologies Tested Up to 1000 K

    NASA Technical Reports Server (NTRS)

    Spry, D. J.; Neudeck, P. G.; Chen, L.; Chang, C. W.; Lukco, D.; Beheim, G. M.

    2015-01-01

    Testing of semiconductor electronics at temperatures above their designed operating envelope is recognized as vital to qualification and lifetime prediction of circuits. This work describes the high temperature electrical testing of prototype 4H silicon carbide (SiC) junction field effect transistor (JFET) integrated circuits (ICs) technology implemented with multilayer interconnects; these ICs are intended for prolonged operation at temperatures up to 773K (500 C). A 50 mm diameter sapphire wafer was used in place of the standard NASA packaging for this experiment. Testing was carried out between 300K (27 C) and 1150K (877 C) with successful electrical operation of all devices observed up to 1000K (727 C).

  9. Insight into metal-enhanced oxidation using barium on 4H-SiC surfaces

    NASA Astrophysics Data System (ADS)

    Chanthaphan, Atthawut; Katsu, Yoshihito; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji

    2016-12-01

    Metal-enhanced oxidation (MEO) using ultrathin Ba layers on 4H-SiC surfaces was investigated by physical and electrical characterizations. We found that while comparable oxidation rates were enhanced for Si- and C-face surfaces even at a low temperature, significant surface and interface roughness were induced by initial MEO termed the incubation period. Depth profiling revealed that although most Ba atoms aggregated on the oxide surface, a tiny amount (˜1014 cm-2) remaining at the oxide interface was responsible for the following stable MEO reaction and the reduced interface state density with the drawbacks of degraded leakage current and breakdown characteristics of SiC-MOS devices.

  10. Compensation Mechanism in High Purity Semi-Insulating 4H-SiC

    DTIC Science & Technology

    2007-01-01

    online 15 March 2007 A study of deep levels in high purity semi-insulating 4H-SiC has been made using temperature dependent Hall effect TDH , thermal and...optical admittance spectroscopies, and secondary ion mass spectrometry SIMS. Thermal activation energies from TDH varied from a low of 0.55 eV to a...high of 1.65 eV. All samples studied showed n-type conduction with the Fermi level in the upper half of the band gap. Fits of the TDH data to

  11. C4H2, HC3N and C2N2 in Titan's atmosphere

    NASA Astrophysics Data System (ADS)

    Kunde, V. G.; Aikin, A. C.; Hanel, R. A.; Jennings, D. E.; Maguire, W. C.; Samuelson, R. E.

    1981-08-01

    Voyager 1 took IR measurements of the atmosphere of Titan, and obtained an average of 346 spectra, mostly from the center of the disk. The compounds C4H2, HC3N, and C2N2 were detected in the atmosphere of Titan. The identification of two compounds containing nitrogen, in addition to HCN, provides further evidence for the abundance of free N2 on Titan. The organic compounds observed in the atmosphere of Titan are summarized in a table, which also indicates the approximate mole fraction for each compound identified previously. The observed compounds originate by reactions of methane and nitrogen radicals in a predominantly nitrogen atmosphere.

  12. Transient collector modulation of 4H-SiC BJTs during switch-on process

    NASA Astrophysics Data System (ADS)

    Yuferev, Valentin S.; Levinshtein, Michael E.; Ivanov, Pavel A.; Zhang, Jon Q.; Palmour, John W.

    2016-09-01

    Main physical features of the collector resistance modulation processes have been studied via a one-dimensional simulation for n+-p-n0-n+ 4H-SiC bipolar junction transistor. The motion dynamics of minority carriers (holes) across the n0 collector layer during the switch-on process is traced. It is demonstrated that the effective modulation of the collector resistance is only possible in the case of a rather fast transistor switch-on. A necessary condition for the fast switch-on is the large amplitude and short leading edge of the base current pulse.

  13. Orientation of the water moiety in CF4-H2O

    NASA Astrophysics Data System (ADS)

    Evangelisti, Luca; Feng, Gang; Gou, Qian; Guidetti, Gloria; Caminati, Walther

    2012-12-01

    The rotational spectrum of CF4-H217O has been investigated by pulsed jet Fourier transform microwave spectroscopy. A symmetric top effective rotational spectrum has been observed, similarly to the case of the parent species (W. Caminati, A. Maris, A. Dell'Erba, P.G. Favero, Angew. Chem. Int. Ed. 45 (2006) 6711). The experimental value of the 17O χaa quadrupole coupling constant, 0.54(1) MHz, allows to determine the average value of the angle between the C2 axis of H2O and the C⋯O line, β = 24°.

  14. Atomic oxidation of large area epitaxial graphene on 4H-SiC(0001)

    SciTech Connect

    Velez-Fort, E.; Ouerghi, A.; Silly, M. G.; Sirtti, F.; Eddrief, M.; Marangolo, M.; Shukla, A.

    2014-03-03

    Structural and electronic properties of epitaxial graphene on 4H-SiC were studied before and after an atomic oxidation process. X-ray photoemission spectroscopy indicates that oxygen penetrates into the substrate and decouples a part of the interface layer. Raman spectroscopy demonstrates the increase of defects due to the presence of oxygen. Interestingly, we observed on the near edge x-ray absorption fine structure spectra a splitting of the π* peak into two distinct resonances centered at 284.7 and 285.2 eV. This double structure smears out after the oxidation process and permits to probe the interface architecture between graphene and the substrate.

  15. Livestock First Reached Southern Africa in Two Separate Events

    PubMed Central

    Sadr, Karim

    2015-01-01

    After several decades of research on the subject, we now know when the first livestock reached southern Africa but the question of how they got there remains a contentious topic. Debate centres on whether they were brought with a large migration of Khoe-speakers who originated from East Africa; or whether the livestock were traded down-the-line among hunter-gatherer communities; or indeed whether there was a long history of diverse small scale population movements in this part of the world, one or more of which ‘infiltrated’ livestock into southern Africa. A new analysis of the distribution of stone toolkits from a sizeable sample of sub-equatorial African Later Stone Age sites, coupled with existing knowledge of the distribution of the earliest livestock remains and ceramics vessels, has allowed us to isolate two separate infiltration events that brought the first livestock into southern Africa just over 2000 years ago; one infiltration was along the Atlantic seaboard and another entered the middle reaches of the Limpopo River Basin. These findings agree well with the latest results of genetic research which together indicate that multiple, small-scale infiltrations probably were responsible for bringing the first livestock into southern Africa. PMID:26295347

  16. Estimate of livestock water use in Nebraska during 1980

    USGS Publications Warehouse

    Steele, E.K.

    1986-01-01

    The estimated volume of 148,120 acre-ft of water used by livestock in Nebraska during 1980 is the second largest (after Texas) volume used for livestock production in the fifty Sates. Although water used by livestock is a small percentage of the total water used in Nebraska, this use has a major impact on the farm economy of the State, as livestock sales accounted for 59% of the total farm market cash receipts in 1980. About 16%, or 23 ,590 acre-ft, of this use is estimated to be from surface water sources, with the remaining 124,530 acre-ft pumped from the State 's groundwater supply. The estimated livestock water use in Nebraska 's 93 counties during 1980 ranged from 340 acre-ft in Hooker County to 6,770 acre-ft in Cherry County. Livestock water use by Hydrologic Units ranged from 20 acre-ft in the Hat Creek basin 10120106) to 10,370 acre-ft in the Elkhorn River basin, and the Natural Resources Districts ' use ranged from 1 ,880 acre-ft in the South Platte NRD to 17,830 acre-ft in the Lower Elkhorn NRD. (Author 's abstract)

  17. Biotechnology developments in the livestock sector in developing countries.

    PubMed

    Onteru, Suneel; Ampaire, Agatha; Rothschild, Max

    2010-01-01

    Global meat and milk consumption is exponentially increasing due to population growth, urbanization and changes in lifestyle in the developing world. This is an excellent opportunity for developing countries to improve the livestock sector by using technological advances. Biotechnology is one of the avenues for improved production in the "Livestock revolution". Biotechnology developments applied to livestock health, nutrition, breeding and reproduction are improving with a reasonable pace in developing countries. Simple bio-techniques such as artificial insemination have been well implemented in many parts of the developing world. However, advanced technologies including transgenic plant vaccines, marker assisted selection, solid state fermentation for the production of fibrolytic enzymes, transgenic fodders, embryo transfer and animal cloning are confined largely to research organizations. Some developing countries such as Taiwan, China and Brazil have considered the commercialization of biotechnology in the livestock sector. Organized livestock production systems, proper record management, capacity building, objective oriented research to improve farmer's income, collaborations with the developed world, knowledge of the sociology of an area and research on new methods to educate farmers and policy makers need to be improved for the creation and implementation of biotechnology advances in the livestock sector in the developing world.

  18. 25 CFR 161.707 - When will BIA impound unauthorized livestock or other property?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false When will BIA impound unauthorized livestock or other... unauthorized livestock or other property? BIA will impound unauthorized livestock or other property under the... livestock or other property refuses to accept delivery of a written notice of trespass and the...

  19. 9 CFR 201.200 - Sale of livestock to a packer on credit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Sale of livestock to a packer on... STOCKYARDS ACT Poultry-Packers and Live Poultry Dealers § 201.200 Sale of livestock to a packer on credit. (a) No packer whose average annual purchases of livestock exceed $500,000 shall purchase livestock...

  20. International trade in livestock and livestock products: the need for a commodity-based approach.

    PubMed

    Thomson, G R; Tambi, E N; Hargreaves, S K; Leyland, T J; Catley, A P; van 't Klooster, G G M; Penrith, M L

    2004-10-02

    International animal health standards designed to facilitate safe trade in livestock and livestock products are set by the Office International des Epizooties (OIE) under the Sanitary and Phytosanitary Agreement of the World Trade Organization (WTO) and documented in the OIE's Terrestrial Animal Health Code. A core principle of the Code is the need for countries to eradicate important transboundary animal diseases (TADs) to reduce the risk of exporting disease to trading partners. International food safety standards are set by the Codex Alimentarius Commission, administered jointly by the World Health Organization and the Food and Agriculture Organization of the United Nations. The goal of global eradication of most TADs is unachievable for the foreseeable future, other than in the case of rinderpest, and this prevents many countries, especially developing nations, from engaging in international trade under WTO rules. This paper proposes an alternative, commodity-based approach to the formulation of international animal health and food safety standards, based on the fact that different commodities pose very different risks when it comes to the spread of human and animal pathogens. Therefore, the risk mitigation strategies required are equally commodity-dependent. The authors conclude that more focused commodity standards would improve access to international markets for all countries, especially those in the developing world. For this objective to be realised, credible and independent certification is required.

  1. Diagnosis of Brucellosis in Livestock and Wildlife

    PubMed Central

    Godfroid, Jacques; Nielsen, Klaus; Saegerman, Claude

    2010-01-01

    Aim To describe and discuss the merits of various direct and indirect methods applied in vitro (mainly on blood or milk) or in vivo (allergic test) for the diagnosis of brucellosis in animals. Methods The recent literature on brucellosis diagnostic tests was reviewed. These diagnostic tests are applied with different goals, such as national screening, confirmatory diagnosis, certification, and international trade. The validation of such diagnostic tests is still an issue, particularly in wildlife. The choice of the testing strategy depends on the prevailing brucellosis epidemiological situation and the goal of testing. Results Measuring the kinetics of antibody production after Brucella spp. infection is essential for analyzing serological results correctly and may help to predict abortion. Indirect ELISAs help to discriminate 1) between false positive serological reactions and true brucellosis and 2) between vaccination and infection. Biotyping of Brucella spp. provides valuable epidemiological information that allows tracing an infection back to the sources in instances where several biotypes of a given Brucella species are circulating. Polymerase chain reaction and new molecular methods are likely to be used as routine typing and fingerprinting methods in the coming years. Conclusion The diagnosis of brucellosis in livestock and wildlife is complex and serological results need to be carefully analyzed. The B. abortus S19 and B. melitensis Rev. 1 vaccines are the cornerstones of control programs in cattle and small ruminants, respectively. There is no vaccine available for pigs or for wildlife. In the absence of a human brucellosis vaccine, prevention of human brucellosis depends on the control of the disease in animals. PMID:20718082

  2. Theoretical study on the reaction of C4H (X˜2Σ+) with CH3OH

    NASA Astrophysics Data System (ADS)

    Huo, Ruiping; Zhang, Xiang; Zhang, Caifeng

    2015-01-01

    The reaction mechanism of linear butadiynyl radical C4H (C1C2C3C4H) with methanol (CH3OH) was studied at the CCSD(T)/aug-cc-pVTZ//BB1K/6-311+G(2d,2p) level. Six different hydrogen abstraction channels were considered, and methyl-H and hydroxyl-H of CH3OH abstractions by C1 atom (M1 and M2) are the two predominant and competitive channels. Further analysis indicated that M1 is a hydrogen atom transfer (HAT) channel while M2 is a proton-coupled electron transfer (PCET) channel. For M1 and M2, the high-pressure rate constants in the temperature range of 100-1400 K were calculated by ICVT/SCT and TST/W methods and the changes of branching ratios with temperature under four pressures (0.1, 1.0, 10 and 100 atm) were also considered by Master equation approach.

  3. Defect Characterization of 4H-SiC Wafers for Power Electronic Device Applications.

    NASA Astrophysics Data System (ADS)

    Cicero, G.; Ferrero, S.; Cocuzza, M.; Giorgis, F.; Mandracci, P.; Ricciardi, C.; Scaltrito, L.; Pirri, C. F.; Richieri, G.; Sgorlon, C.

    2002-03-01

    Silicon carbide is a wide band gap semiconductor, interesting for its physical properties such as high breakdown field, high saturated drift velocity and high thermal conductivity, which has been intensively studied in the last years. Although the high potentiality of this material, the SiC technology shows at the moment some limitations and requires further study in order to obtain electronic devices with the same quality standards of the Si technology. Indeed, the reliability of SiC-based devices is strictly correlated to the defects present in the crystalline structure. We have focused our investigation on 4H-SiC wafers and on 4H epitaxial layers in order to determine in both the situations the different type of defects. A preliminary investigation has been performed by optical microscopy and Scanning Electron Microscopy with the aim to evidence the defect morphology on large scale. A deeper insight on the defects typology has been obtained by Atomic Force Microscopy, Profilometer technique, Micro-Raman and Micro-Photoluminescence spectroscopies. Different types of defects such as micropipes, comets, super dislocations, etch pits and so on, have been characterized finding particular physical finger-prints. This investigation is aimed at correlating the defects and the electrical properties of SiC for power electronic device applications.

  4. Microwave photoconductivity decay characterization of high-purity 4H-SiC substrates

    NASA Astrophysics Data System (ADS)

    Kumar, R. J.; Borrego, J. M.; Gutmann, R. J.; Jenny, J. R.; Malta, D. P.; Hobgood, H. McD.; Carter, C. H.

    2007-07-01

    A microwave photoconductivity decay (MPCD) technique, which probes conductivity change in wafers in response to either an above-band-gap or below-band-gap laser pulse, has been used to characterize recombination lifetime in high-purity 4H-SiC substrates produced with three different anneal processes. The above-band-gap (266nm) decay times vary from ˜10ns to tens of microseconds in the 4H-SiC substrates depending on the wafer growth parameters. Wafers produced using the three processes A (as-grown), B (annealed at 2000°C), and C (annealed at 2600°C) have decay times of 10-20ns, 50-500ns, and tens of microseconds, respectively. The differences in decay times are attributed to low, medium, and high densities of recombination centers in process C, B, and A wafers, respectively. The MPCD results correlate with other characterization results such as deep level transient spectroscopy, which also showed that the 2600°C anneal process significantly reduces defect densities, resulting in the enhanced recombination lifetimes. Modeling and one-dimensional simulations indicate a trapping center closer to the conduction band results in a longer MPCD decay transient, but such a trapping based model for the enhanced lifetimes is not compatible with the wide range of experimental characterization results described in this work, which indicate an annealing out of recombination centers at 2600°C.

  5. Schottky barrier detection devices having a 4H-SiC n-type epitaxial layer

    SciTech Connect

    Mandal, Krishna C.; Terry, J. Russell

    2016-12-06

    A detection device, along with methods of its manufacture and use, is provided. The detection device can include: a SiC substrate defining a substrate surface cut from planar to about 12.degree.; a buffer epitaxial layer on the substrate surface; a n-type epitaxial layer on the buffer epitaxial layer; and a top contact on the n-type epitaxial layer. The buffer epitaxial layer can include a n-type 4H--SiC epitaxial layer doped at a concentration of about 1.times.10.sup.15 cm.sup.-3 to about 5.times.10.sup.18 cm.sup.-3 with nitrogen, boron, aluminum, or a mixture thereof. The n-type epitaxial layer can include a n-type 4H--SiC epitaxial layer doped at a concentration of about 1.times.10.sup.13 cm.sup.-3 to about 5.times.10.sup.15 cm.sup.-3 with nitrogen. The top contact can have a thickness of about 8 nm to about 15 nm.

  6. n-ZnO/p-4H-SiC diode: Structural, electrical, and photoresponse characteristics

    SciTech Connect

    Guziewicz, M. Jung, W.

    2015-09-07

    Epitaxial n-type ZnO film has been grown, on a commercial 5 μm thick p-type 4H-SiC(00.1) Al doped epilayer, by atomic layer deposition. A full width at half maximum of the ZnO 00.2 diffraction peak rocking curve of 0.34°{sup  }± 0.02° has been measured. Diodes formed on the n-ZnO/p-4H-SiC heterostructure show rectifying behavior with a forward to reverse current ratio at the level of 10{sup 9} at ±4 V, a leakage current density of ∼6 × 10{sup −8} A/cm{sup 2}, and a low ideality factor equal to 1.17 ± 0.04. In addition, the diodes exhibit selective photoresponse with a maximum at 367 nm, and with a current increase of ∼10{sup 3} under illuminations with respect to the dark value, which makes such devices prospective candidates for ultraviolet light sensors.

  7. Exploration of Defects in 4H-SiC MOSFETs via Spin Dependent Charge Pumping

    NASA Astrophysics Data System (ADS)

    Anders, Mark; Lenahan, Patrick; Lelis, Aivars

    4H-SiC MOSFETs have great promise for use in high temperature and high voltage applications. Unfortunately, defects at the SiC/SiO2 interface reduce the performance of these devices. Previously, our group utilized electrically detected magnetic resonance (EDMR) detected via spin dependent recombination (SDR) to identify such SiC/SiO2 interface defects utilizing the bipolar amplification (BAE) biasing scheme; we observed SiC silicon vacancies, E-prime centers, and hydrogen complexed E-prime centers. All of these defects must have levels around the middle of the SiC band gap because they are effective recombination centers. We expanded our studies to include EDMR detection via spin dependent charge pumping (SDCP) at low field, X band, and K band, allowing EDMR exploration of nearly the entire 4H-SiC band gap. Perhaps the most important finding of the (nearly) full band gap measurements is the absence of the carbon dangling bond spectrum in the SDCP. Additionally, in nMOSFETs, we observe an SDCP EDMR spectrum dominated by a silicon vacancy, whereas in pMOSFETs, we also observe a strong, nearly isotropic single line spectrum with g = 2.00244 and 2.00248 when the c-axis is nearly parallel and perpendicular to the magnetic field, respectively. The results suggest that silicon vacancy centers dominate nMOSFET interfaces whereas additional defects clearly play important roles in pMOSFETs.

  8. Characterization of V-shaped defects in 4H-SiC homoepitaxial layers

    SciTech Connect

    Zhang, Lihua; Su, Dong; Kisslinger, Kim; Stach, Eric; Chung, Gil; Zhang, Jie; Thomas, Bernd; Sanchez, Edward K; Mueller, Stephan G.; Hansen, Darren; Loboda, Mark J.; Wu, Fangzhen; Wang, Huanhuan; Raghothamachar, Balaji; Dudley, Michael

    2014-12-04

    Synchrotron white beam x-ray topography images show that faint needle-like surface morphological features observed on the Si-face of 4H-SiC homoepitaxial layers using Nomarski optical microscopy are associated with V shaped stacking faults in the epilayer. KOH etching of the V shaped defect reveals small oval pits connected by a shallow line which corresponding to the surface intersections of two partial dislocations and the stacking fault connecting them. Transmission electron microscopy (TEM) specimens from regions containing the V shaped defects were prepared using focused ion beam milling, and stacking sequences of (85), (50) and (63) are observed at the faulted region with high resolution TEM. In order to study the formation mechanism of V shaped defect, low dislocation density 4H-SiC substrates were chosen for epitaxial growth, and the corresponding regions before and after epitaxy growth are compared in SWBXT images. It is found that no defects in the substrate are directly associated with the formation of the V shaped defect. Simulation results of the contrast from the two partial dislocations associated with V shaped defect in synchrotron monochromatic beam x-ray topography reveals the opposite sign nature of their Burgers vectors. Therefore, a mechanism of 2D nucleation during epitaxy growth is postulated for the formation of the V shaped defect, which requires elimination of non-sequential 1/4[0001] bilayers from the original structure to create the observed faulted stacking sequence.

  9. Characterization of V-shaped defects in 4H-SiC homoepitaxial layers

    DOE PAGES

    Zhang, Lihua; Su, Dong; Kisslinger, Kim; ...

    2014-12-04

    Synchrotron white beam x-ray topography images show that faint needle-like surface morphological features observed on the Si-face of 4H-SiC homoepitaxial layers using Nomarski optical microscopy are associated with V shaped stacking faults in the epilayer. KOH etching of the V shaped defect reveals small oval pits connected by a shallow line which corresponding to the surface intersections of two partial dislocations and the stacking fault connecting them. Transmission electron microscopy (TEM) specimens from regions containing the V shaped defects were prepared using focused ion beam milling, and stacking sequences of (85), (50) and (63) are observed at the faulted regionmore » with high resolution TEM. In order to study the formation mechanism of V shaped defect, low dislocation density 4H-SiC substrates were chosen for epitaxial growth, and the corresponding regions before and after epitaxy growth are compared in SWBXT images. It is found that no defects in the substrate are directly associated with the formation of the V shaped defect. Simulation results of the contrast from the two partial dislocations associated with V shaped defect in synchrotron monochromatic beam x-ray topography reveals the opposite sign nature of their Burgers vectors. Therefore, a mechanism of 2D nucleation during epitaxy growth is postulated for the formation of the V shaped defect, which requires elimination of non-sequential 1/4[0001] bilayers from the original structure to create the observed faulted stacking sequence.« less

  10. High-purity semi-insulating 4H-SiC for microwave device applications

    NASA Astrophysics Data System (ADS)

    Jenny, J. R.; Malta, D. P.; Müller, St G.; Powell, A. R.; Tsvetkov, V. F.; Hobgood, H. Mcd; Glass, R. C.; Carter, C. H., Jr.

    2003-05-01

    High-purity, semi-insulating (HPSI) 4H-SiC crystals with diameters up to 75 mm have been grown by the seeded sublimation technique without the intentional introduction of elemental deep-level dopants, such as vanadium. Wafers cut from these crystals exhibit homogeneous activation energies near mid gap and thermally stable semi-insulating (SI) behavior (>109 ohm-cm) throughout device processing. Secondary ion mass spectroscopy, deep-level transient spectroscopy, optical admittance spectroscopy, and electron paramagnetic resonance data suggest that the SI behavior originates from several deep levels associated with intrinsic point defects. Micropipe densities in HPSI substrates have been demonstrated to be as low as 10 cm-2 in 2-in. substrates, and the room-temperature thermal conductivity of this material is near the theoretical maximum of 5 W/cm·K for 4H-SiC. Devices fabricated on these HPSI wafers do not exhibit any substrate related back-gating effects and have power densities as high as 5.2 W/mm with 63% power added efficiency.

  11. Defect studies of Vanadium doped 4H-SiC using optical admittance spectroscopy

    NASA Astrophysics Data System (ADS)

    Lee, Wonwoo

    2005-03-01

    Semi-insulating SiC is an excellent candidate for a variety of applications, including microwave FET's and other devices for high power and high temperature applications. Vanadium acts as an amphoteric impurity in 4H-SiC with a V^3+/4+ acceptor level thought to be within 1 eV of the conduction band edge and a V^4+/5+ donor level known to be 1.6 eV below the conduction band edge. Vanadium is an efficient carrier trap and recombination center. We have studied vanadium doped 4H-SiC with the optical admittance spectroscopy (OAS) at room temperature. After taking into account phonon-assisted optical transitions, the estimated threshold energies can be compared with defect levels measured using thermal techniques. Compared with data reported in the literature, our results show that the defect level Ec -1.5 eV is close to the vanadium donor level and the other level Ec -0.67 eV is within the range of the value attributed to the vanadium acceptor level.

  12. Experimental characterization of a 4H SiC high voltage current limiting device

    NASA Astrophysics Data System (ADS)

    Nallet, F.; Planson, D.; Godignon, P.; Locatelli, M. L.; Lazar, M.; Chante, J. P.

    2001-12-01

    The aim of this paper is to show the first experimental results of a 600 V 4H-SiC current limiting device. This device limits the current which flows through it as the bias voltage between its two contacts increases. The static curves obtained from the first process run (T=300 K) show a current limitation capability with a saturation voltage ranging from 10 to 15 V. The device electrical characterization shows a R ON≈150 mΩ cm 2 and a current density of 150 A cm -2 under 50 V. The forward conduction is ensured by an N type implanted channel (doping species: nitrogen) on top of an P + implanted layer (doping species: aluminum). The post-implantation annealing of 1700 °C/30 min leads to a good electrical activation (80%) of the N channel/P + layer (analyzed by C(V) and SIMS methods) and a good channel mobility (100 cm 2 V -1 s -1 for a 2×10 17 cm-3 N compensated doping concentration). The prototypes of the second process run reach a saturation current density of 900 A cm -2 with a specific on-resistance of 13 mΩ cm 2. The 4H-SiC current limiting devices of the second run belong to the best set of Accu-MOSFETs devices reported in the literature.

  13. High-voltage 4H-SiC PiN diodes with the etched implant junction termination extension

    NASA Astrophysics Data System (ADS)

    Li, Juntao; Xiao, Chengquan; Xu, Xingliang; Dai, Gang; Zhang, Lin; Zhou, Yang; Xiang, An; Yang, Yingkun; Zhang, Jian

    2017-02-01

    This paper presents the design and fabrication of an etched implant junction termination extension (JTE) for high-voltage 4H-SiC PiN diodes. Unlike the conventional JTE structure, the proposed structure utilizes multiple etching steps to achieve the optimum JTE concentration range. The simulation results show that the etched implant JTE method can improve the blocking voltage of SiC PiN diodes and also provides broad process latitude for parameter variations, such as implantation dose and activation annealing condition. The fabricated SiC PiN diodes with the etched implant JTE exhibit a highest blocking voltage of 4.5 kV and the forward on-state voltage of 4.6 V at room temperature. These results are of interest for understanding the etched implant method in the fabrication of high-voltage power devices. Project supported by the Science and Technology Development Foundation of China Academy of Engineering Physics (No. 2014A05011) and the Special Foundation of President of China Academy of Engineering Physics (No. 2014-1-100).

  14. Influences of ICP etching damages on the electronic properties of metal field plate 4H-SiC Schottky diodes

    NASA Astrophysics Data System (ADS)

    Hui, Wang; Yingxi, Niu; Fei, Yang; Yong, Cai; Zehong, Zhang; Zhongming, Zeng; Minrui, Wang; Chunhong, Zeng; Baoshun, Zhang

    2015-10-01

    Inductively coupled plasma (ICP) etching of 4H-SiC using SF6/O2 gas mixture was studied systematically and the effect of etching was examined by metal field plate SiC Schottky diodes (SBDs). It was found that the etch rate as well as SiC surface morphology were related with ICP power, RF power, pressure, the flow of SF6 and O2. Etching damages (the cone-in-pits and pits) generated at high chuck self-bias were observed, and they were thought to be caused by SiC defects. The degradation of both the reverse and forward I-V performances of SiC SBDs was ascribed to the cone-in-pits and pits. Moreover, the absolute value of forward current is even less than the reverse counterpart in the absolute value voltage range of 0-50 V for SiC SBDs with etching damages. Project supported by the Suzhou Research Fund (No. BY2011129) and the State Grid Corporation of China Research Fund (No. 525500140003).

  15. Understanding Life Skills Gained from and Reasons for Youth Participation in the Tennessee 4-H Sheep Skillathon

    ERIC Educational Resources Information Center

    Davis, Terra Kimes; Stripling, Christopher T.; Stephens, Carrie A.; Loveday, H. Dwight

    2016-01-01

    The high number of U.S. youth exhibiting at-risk behavior points to a lack of life skills development. We determined the effects of participating in one state's 4-H sheep skillathon on youths' life skills development and the youths' reasons for participating. The target population was 2014 Tennessee 4-H Sheep Skillathon participants (N = 153), and…

  16. Family Diversity in a Youth Organization: Involvement of Single-Parent Families and Stepfamilies in 4-H.

    ERIC Educational Resources Information Center

    Ganong, Lawrence H.

    1993-01-01

    Evaluated involvement of children from single-parent and stepparent households in 4-H clubs. Used case study approach, with data collected via written materials; interviews with 4-H staff; and mailed questionnaires from professional staff, paraprofessionals, and parents. Children from single-parent households were found to be underrepresented, as…

  17. Characterization of the Minimum Energy Paths for the Ring Closure Reactions of C4H3 with Acetylene

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.

    1995-01-01

    The ring closure reaction of C4H3 with acetylene to give phenyl radical is one proposed mechanism for the formation of the first aromatic ring in hydrocarbon combustion. There are two low-lying isomers of C4H3; 1-dehydro-buta-l-ene-3-yne (n-C4H3) and 2-dehydro-buta-l-ene-3-yne (iso-C4H3). It has been proposed that only n-C4H3 reacts with acetylene to give phenyl radical, and since iso-C4H3 is more stable than n-C4H3, formation of phenyl radical by this mechanism is unlikely. We report restricted Hartree-Fock (RHF) plus singles and doubles configuration interaction calculations with a Davidson's correction (RHF+1+2+Q) using the Dunning correlation consistent polarized valence double zeta basis set (cc-pVDZ) for stationary point structures along the reaction pathway for the reactions of n-C4H3 and iso-C4H3 with acetylene. n-C4H3 plus acetylene (9.4) has a small entrance channel barrier (17.7) (all energetics in parentheses are in kcal/mol with respect to iso-C4H3 plus acetylene) and the subsequent closure steps leading to phenyl radical (-91.9) are downhill with respect to the entrance channel barrier. Iso-C4H3 Plus acetylene also has an entrance channel barrier (14.9) and there is a downhill pathway to 1-dehydro-fulvene (-55.0). 1-dehydro-fulvene can rearrange to 6-dehydro-fulvene (-60.3) by a 1,3-hydrogen shift over a barrier (4.0), which is still below the entrance channel barrier, from which rearrangement to phenyl radical can occur by a downhill pathway. Thus, both n-C4H3 and iso-C4H3 can react with acetylene to give phenyl radical with small barriers.

  18. Fabrication and characterization of the normally-off N-channel lateral 4H-SiC metal-oxide-semiconductor field-effect transistors

    NASA Astrophysics Data System (ADS)

    Qing-Wen, Song; Xiao-Yan, Tang; Yan-Jing, He; Guan-Nan, Tang; Yue-Hu, Wang; Yi-Meng, Zhang; Hui, Guo; Ren-Xu, Jia; Hong-Liang, Lv; Yi-Men, Zhang; Yu-Ming, Zhang

    2016-03-01

    In this paper, the normally-off N-channel lateral 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFFETs) have been fabricated and characterized. A sandwich- (nitridation-oxidation-nitridation) type process was used to grow the gate dielectric film to obtain high channel mobility. The interface properties of 4H-SiC/SiO2 were examined by the measurement of HF I-V, G-V, and C-V over a range of frequencies. The ideal C-V curve with little hysteresis and the frequency dispersion were observed. As a result, the interface state density near the conduction band edge of 4H-SiC was reduced to 2 × 1011 eV-1·cm-2, the breakdown field of the grown oxides was about 9.8 MV/cm, the median peak field-effect mobility is about 32.5 cm2·V-1·s-1, and the maximum peak field-effect mobility of 38 cm2·V-1·s-1 was achieved in fabricated lateral 4H-SiC MOSFFETs. Projcet supported by the National Natural Science Foundation of China (Grant Nos. 61404098, 61176070, and 61274079), the Doctoral Fund of Ministry of Education of China (Grant Nos. 20110203110010 and 20130203120017), the National Key Basic Research Program of China (Grant No. 2015CB759600), and the Key Specific Projects of Ministry of Education of China (Grant No. 625010101).

  19. Direct and indirect impacts of crop-livestock organization on mixed crop-livestock systems sustainability: a model-based study.

    PubMed

    Sneessens, I; Veysset, P; Benoit, M; Lamadon, A; Brunschwig, G

    2016-11-01

    Crop-livestock production is claimed more sustainable than specialized production systems. However, the presence of controversial studies suggests that there must be conditions of mixing crop and livestock productions to allow for higher sustainable performances. Whereas previous studies focused on the impact of crop-livestock interactions on performances, we posit here that crop-livestock organization is a key determinant of farming system sustainability. Crop-livestock organization refers to the percentage of the agricultural area that is dedicated to each production. Our objective is to investigate if crop-livestock organization has both a direct and an indirect impact on mixed crop-livestock (MC-L) sustainability. In that objective, we build a whole-farm model parametrized on representative French sheep and crop farming systems in plain areas (Vienne, France). This model permits simulating contrasted MC-L systems and their subsequent sustainability through the following indicators of performance: farm income, production, N balance, greenhouse gas (GHG) emissions (/kg product) and MJ consumption (/kg product). Two MC-L systems were simulated with contrasted crop-livestock organizations (MC20-L80: 20% of crops; MC80-L20: 80% of crops). A first scenario - constraining no crop-livestock interactions in both MC-L systems - permits highlighting that crop-livestock organization has a significant direct impact on performances that implies trade-offs between objectives of sustainability. Indeed, the MC80-L20 system is showing higher performances for farm income (+44%), livestock production (+18%) and crop GHG emissions (-14%) whereas the MC20-L80 system has a better N balance (-53%) and a lower livestock MJ consumption (-9%). A second scenario - allowing for crop-livestock interactions in both MC20-L80 and MC80-L20 systems - stated that crop-livestock organization has a significant indirect impact on performances. Indeed, even if crop-livestock interactions permit

  20. Steady-state balance model to calculate the indoor climate of livestock buildings, demonstrated for finishing pigs

    NASA Astrophysics Data System (ADS)

    Schauberger, G.; Piringer, M.; Petz, E.

    The indoor climate of livestock buildings is of importance for the well-being and health of animals and their production performance (daily weight gain, milk yield etc). By using a steady-state model for the sensible and latent heat fluxes and the CO2 and odour mass flows, the indoor climate of mechanically ventilated livestock buildings can be calculated. These equations depend on the livestock (number of animals and how they are kept), the insulation of the building and the characteristics of the ventilation system (ventilation rate). Since the model can only be applied to animal houses where the ventilation systems are mechanically controlled (this is the case for a majority of finishing pig units), the calculations were done for an example of a finishing pig unit with 1000 animal places. The model presented used 30 min values of the outdoor parameters temperature and humidity, collected over a 2-year period, as input. The projected environment inside the livestock building was compared with recommended values. The duration of condensation on the inside surfaces was also calculated.

  1. Diversity in livestock resources in pastoral systems in Africa.

    PubMed

    Kaufmann, B A; Lelea, M A; Hulsebusch, C G

    2016-11-01

    Pastoral systems are important producers and repositories of livestock diversity. Pastoralists use variability in their livestock resources to manage high levels of environmental variability in economically advantageous ways. In pastoral systems, human-animal-environment interactions are the basis of production and the key to higher productivity and efficiency. In other words, pastoralists manage a production system that exploits variability and keeps production costs low. When differentiating, characterising and evaluating pastoral breeds, this context-specific, functional dimension of diversity in livestock resources needs to be considered. The interaction of animals with their environment is determined not only by morphological and physiological traits but also by experience and socially learned behaviour. This high proportion of non-genetic components determining the performance of livestock means that current models for analysing livestock diversity and performance, which are based on genetic inheritance, have limited ability to describe pastoral performance. There is a need for methodological innovations to evaluate pastoral breeds and animals, since comparisons based on performance 'under optimal conditions' are irrelevant within this production system. Such innovations must acknowledge that livestock or breed performance is governed by complex human-animal-environment interactions, and varies through time and space due to the mobile and seasonal nature of the pastoral system. Pastoralists' breeding concepts and selection strategies seem to be geared towards improving their animals' capability to exploit variability, by - among other things - enhancing within-breed diversity. In-depth studies of these concepts and strategies could contribute considerably towards developing methodological innovations for the characterisation and evaluation of pastoral livestock resources.

  2. Linking human health and livestock health: a “one-health” platform for integrated analysis of human health, livestock health, and economic welfare in livestock dependent communitities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    For most rural households in sub-Saharan Africa, healthy livestock play a key role in minimizing the burden associated with zoonotic diseases, and in meeting household nutritional and socio-economic needs. Although these relationships are recognized, they are complex and there is limited data on the...

  3. Micronutrients in Soils, Crops, and Livestock

    NASA Astrophysics Data System (ADS)

    Gupta, Umesh C.; Wu, Kening; Liang, Siyuan

    in forages, which are sufficient for optimum crop yields, are not adequate to meet the needs of livestock. Selenium is a trace mineral, which is not required by plants, and maximum forage yields can be obtained on soils with very low amounts of soil Se. However, if animals are fed feed crops and forages with low Se, they could suffer from serious muscular disorders and other diseases. White muscle disease caused by Se deficiency is the most common disorder and is found in calves and lambs. Sufficiency levels of micronutrients for crops have been discussed in relation to the animal requirement.

  4. Scenario-neutral Food Security Risk Assessment: A livestock Heat Stress Case Study

    NASA Astrophysics Data System (ADS)

    Broman, D.; Rajagopalan, B.; Hopson, T. M.

    2015-12-01

    Food security risk assessments can provide decision-makers with actionable information to identify critical system limitations, and alternatives to mitigate the impacts of future conditions. The majority of current risk assessments have been scenario-led and results are limited by the scenarios - selected future states of the world's climate system and socioeconomic factors. A generic scenario-neutral framework for food security risk assessments is presented here that uses plausible states of the world without initially assigning likelihoods. Measures of system vulnerabilities are identified and system risk is assessed for these states. This framework has benefited greatly by research in the water and natural resource fields to adapt their planning to provide better risk assessments. To illustrate the utility of this framework we develop a case study using livestock heat stress risk within the pastoral system of West Africa. Heat stress can have a major impact not only on livestock owners, but on the greater food production system, decreasing livestock growth, milk production, and reproduction, and in severe cases, death. A heat stress index calculated from daily weather is used as a vulnerability measure and is computed from historic daily weather data at several locations in the study region. To generate plausible states, a stochastic weather generator is developed to generate synthetic weather sequences at each location, consistent with the seasonal climate. A spatial model of monthly and seasonal heat stress provide projections of current and future livestock heat stress measures across the study region, and can incorporate in seasonal climate and other external covariates. These models, when linked with empirical thresholds of heat stress risk for specific breeds offer decision-makers with actionable information for use in near-term warning systems as well as for future planning. Future assessment can indicate under which states livestock are at greatest risk

  5. Materials Data on ZnP4H16(NO8)2 (SG:2) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  6. Materials Data on CoP4H16(NO8)2 (SG:2) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  7. Materials Data on CuAs4(H5O8)2 (SG:2) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  8. Materials Data on MgB4(H9O8)2 (SG:2) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  9. Materials Data on K4H4WC8(N4O)2 (SG:62) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-05-26

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  10. Materials Data on KErP4(H2O9)2 (SG:15) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-11

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  11. Materials Data on K3Mo4H6O16F (SG:2) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-04

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  12. Materials Data on Na2TiSi4H4O13 (SG:14) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-04

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  13. Materials Data on As4H24C8S7N2 (SG:14) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-11

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  14. Materials Data on Sb4H8C2S7N (SG:64) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-04

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on MnGe4H24C8(S5N)2 (SG:82) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-11

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Materials Data on Ca4MgB4H6(CO9)2 (SG:12) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. Materials Data on NaGdRe4(H2O5)4 (SG:118) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-04

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  18. Materials Data on Cu4H24C13N7Cl (SG:9) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-04

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  19. Materials Data on Al4P4H11C3NO18 (SG:2) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-05-31

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  20. Materials Data on Zn8B4H3O15F (SG:4) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-04

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  1. Materials Data on Al6ZnP4(H4O7)4 (SG:2) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  2. Materials Data on YbKP4(H4O9)2 (SG:15) by Materials Project

    SciTech Connect

    Kristin Persson

    2016-02-11

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  3. Characterization and Modeling of 4H-SiC Lateral MOSFETs for Integrated Circuit Design

    SciTech Connect

    Mudholkar, M; Mantooth, HA

    2013-06-01

    A new process in 4H-SiC is developed that features n-type buried and inversion channel lateral MOSFETs that are fabricated with several different channel lengths (2-8 mu m) and widths (8-32 mu m) and characterized over a wide temperature range (25 degrees C-225 degrees C). It is shown that the on-resistance of enhancement-mode SiC MOSFETs reduces with temperature despite a reduction in inversion mobility because of the interaction of interface states with temperature. To enable integrated circuit development using the developed MOSFETs, their electrical characteristics are modeled over geometry and temperature using the industry standard PSP MOSFET model. A new mathematical formulation to describe the presence of the interface states is also developed and implemented in the PSP model, and excellent agreement is shown between measurement and simulation using the modified PSP model.

  4. 2-Amino-4-(nitroalkyl)-4H-chromene-3-carbonitriles as New Cytotoxic Agents

    PubMed Central

    Zonouzi, Afsaneh; Mirzazadeh, Roghieh; Safavi, Maliheh; Kabudanian Ardestani, Sussan; Emami, Saeed; Foroumadi, Alireza

    2013-01-01

    A series of 2-amino-4-(nitroalkyl)-4H-chromene-3-carbonitriles were synthesized by an efficient multicomponent reaction in aqueous media using DBU as a catalyst at room temperature. Mild condition, environment friendly procedure and excellent yields are the main advantages of this procedure. The cytotoxic activity of target compounds were evaluated against three cancer cell lines MDA-MB-231, MCF-7 and T47D in comparison with etoposide as reference drug. Generally, all compounds showed good cell growth inhibitory activity with IC50 values less than 30 μg/mL. Their activities were comparable or more potent than standard drug etoposide. The 6-bromo- derivatives 7e and 7f showed promising cytotoxic activity with IC50 values in the range of 3.46–18.76 μg/mL, being more potent than etoposide against all tested cell lines. PMID:24523747

  5. Synthesis of a new class of pyrrolo[3,4-h]quinazolines with antimitotic activity.

    PubMed

    Spanò, Virginia; Montalbano, Alessandra; Carbone, Anna; Parrino, Barbara; Diana, Patrizia; Cirrincione, Girolamo; Castagliuolo, Ignazio; Brun, Paola; Issinger, Olaf-Georg; Tisi, Silvia; Primac, Irina; Vedaldi, Daniela; Salvador, Alessia; Barraja, Paola

    2014-03-03

    A new series of pyrrolo[3,4-h]quinazolines was conveniently prepared with a broad substitution pattern. A large number of derivatives was obtained and the cellular cytotoxicity was evaluated in vitro against 5 different human tumor cell lines with GI₅₀ values reaching the low micromolar level (1.3-19.8 μM). These compounds were able to induce cell death mainly by apoptosis through a mitochondrial dependent pathway. Selected compounds showed antimitotic activity and a reduction of tubulin polymerization in a concentration-dependent manner. Moreover, they showed anti-angiogenic properties since reduced in vitro endothelial cell migration and disrupted HUVEC capillary-like tube network in Matrigel.

  6. Pyrazolo[3,4-h]quinolines promising photosensitizing agents in the treatment of cancer.

    PubMed

    Spanò, Virginia; Parrino, Barbara; Carbone, Anna; Montalbano, Alessandra; Salvador, Alessia; Brun, Paola; Vedaldi, Daniela; Diana, Patrizia; Cirrincione, Girolamo; Barraja, Paola

    2015-09-18

    A new series of pyrazolo[3,4-h]quinolines, heteroanalogues of angelicin was conveniently prepared with a broad substitution pattern. A large number of derivatives was obtained and the cellular photocytotoxicity was evaluated in vitro against 5 different human tumor cell lines with GI50 values reaching the nanomolar level (14.52-0.04 μM). Selected compounds were able to photoinduce a massive cell death with the involvement of mitochondria. Their photodamage cellular targets were proteins and lipids and they did not cause any kind of DNA photodamage. This latter event is of considerable importance in the modulation of long term side effects, generally associated with the use of classical furocoumarins.

  7. 4H-SiC UV Photo Detector with Large Area and Very High Specific Detectivity

    NASA Technical Reports Server (NTRS)

    Yan, Feng; Shahid, Aslam; Franz, David; Xin, Xiaobin; Zhao, Jian H.; Zhao, Yuegang; Winer, Maurice

    2004-01-01

    Pt/4H-SiC Schottky photodiodes have been fabricated with the device areas up to 1 sq cm. The I-V characteristics and photo-response spectra have been measured and analyzed. For a 5 mm x 5 mm area device leakage current of 1 x 10(exp 15)A at zero bias and 1.2 x 10(exp 14)A at -IV have been established. The quantum efficiency is over 30% from 240nm to 320nm. The specific detectivity, D(sup *), has been calculated from the directly measured leakage current and quantum efficiency data and are shown to be higher than 10(exp 15) cmHz(sup 1/2)/W from 210nm to 350nm with a peak D(sup *) of 3.6 x 10(exp 15)cmH(sup 1/2)/W at 300nm.

  8. An Integrated Gate Driver in 4H-SiC for Power Converter Applications

    SciTech Connect

    Ericson, Milton Nance; Frank, Steven Shane; Britton, Charles; Janke, Devon D; Ezell, N Dianne Bull; Ryu, Sei_Hyung; Mantooth, Alan; Francis, Dr. Matt; Lanmichhane, Dr. Ranjan; Shepherd, Dr. Paul; Glover, Dr. Michael; Whitaker, Mr. Bret; Cole, Mr. Zach; Passmore, Mr. Brandon; Mcnutt, Tyler

    2014-01-01

    A gate driver fabricated in a 2-um 4H silicon carbide (SiC) process is presented. This process was optimized for vertical power MOSFET fabrication but accommodated integration of a few low-voltage device types including N-channel MOSFETs, resistors, and capacitors. The gate driver topology employed incorporates an input level translator, variable power connections, and separate power supply connectivity allowing selection of the output signal drive amplitude. The output stage utilizes a source follower pull-up device that is both overdriven and body source connected to improve rise time behavior. Full characterization of this design driving a SiC power MOSFET is presented including rise and fall times, propagation delays, and power consumption. All parameters were measured to elevated temperatures exceeding 300 C. Details of the custom test system hardware and software utilized for gate driver testing are also provided.

  9. 4H-SiC trench IGBT with lower on-state voltage drop

    NASA Astrophysics Data System (ADS)

    Liu, Yan-juan; Wang, Ying; Yu, Cheng-hao; Fei-Cao

    2017-03-01

    In this paper, a new 4H-SiC trench-gate IGBT structure incorporated a P+ shielding region in the emitter side is proposed in order to reduce the on-state voltage drop. Through the 2-D ATLAS simulation, the characteristics of the proposed structure are investigated and compared with the conventional structure. The simulation results indicate that the proposed structure exhibits an improvement in the following. Firstly, the on-state voltage drop is reduced by 32.75%. Secondly, the differential specific on-resistance is reduced by 42.33%. Finally, under the same on-state voltage drop, the turn-off energy is reduced more than 50.00%. At the end of the paper, it is explored that what effects the physical parameter of the P+ shielding region in the proposed structure have on the steady state performances.

  10. Low-energy electron scattering from C{sub 4}H{sub 9}OH isomers

    SciTech Connect

    Bettega, M. H. F.; Winstead, C.; McKoy, V.

    2010-12-15

    We present differential, integral, and momentum-transfer cross sections for elastic scattering of low-energy electrons by three butanol isomers, isobutanol, t-butanol, and 2-butanol. Our results were calculated with the Schwinger multichannel method in the static-exchange plus polarization approximation for collision energies from 1 to 50 eV. The present results are compared with previous calculations and measurements for the remaining C{sub 4}H{sub 9}OH isomer, n-butanol [Khakoo et al., Phys. Rev. A 78, 062714 (2008)]. Distinctive behavior is observed in the differential cross sections at collision energies between 5 and 10 eV. In particular, whereas n-butanol exhibits an f-wave scattering pattern, the other isomers exhibit d-wave behavior. A similar pattern is found in the related alkanes when comparing straight-chain versus branched isomers. We discuss the possible connection of this behavior to shape resonances that influence the scattering.

  11. 4H-SiC surface energy tuning by nitrogen up-take

    NASA Astrophysics Data System (ADS)

    Pitthan, E.; Amarasinghe, V. P.; Xu, C.; Gustafsson, T.; Stedile, F. C.; Feldman, L. C.

    2017-04-01

    Surface energy modification and surface wettability of 4H silicon carbide (0001) as a function of nitrogen adsorption is reported. The surface wettability is shown to go from primarily hydrophilic to hydrophobic and the surface energy was significantly reduced with increasing nitrogen incorporation. These changes are investigated by x-ray photoelectron spectroscopy and contact angle measurements. The surface energy was quantitatively determined by the Fowkes model and interpreted primarily in terms of the variation of the surface chemistry with nitrogen coverage. Variable control of SiC surface energies with a simple and controllable atomic additive such as nitrogen that is inert to etching, stable against time, and also effective in electrical passivation, can provide new opportunities for SiC biomedical applications, where surface wetting plays an important role in the interaction with the biological interfaces.

  12. High resolution alpha particle detectors based on 4H-SiC epitaxial layer

    NASA Astrophysics Data System (ADS)

    Zat'ko, B.; Dubecký, F.; Šagátová, A.; Sedlačová, K.; Ryć, L.

    2015-04-01

    We fabricated and characterized 4H-SiC Schottky diodes as a spectrometric detector of alpha particles. A thin blocking contact of Ni/Au (15 nm) was used to minimize the influence on alpha particles energy. Current-voltage characteristics of the detector were measured and a low current density below 0.3 nAcm-2 was observed at room temperature. 239Pu241Am244Cm was used as a source of alpha particles within the energy range between 5.1 MeV and 5.8 MeV for detector testing. The charge collection efficiency close to 100 % at reverse bias exceeding 50 V was determined. The best spectrometric performance shows a pulse height spectrum at a reverse bias of 200 V giving an energy resolution of 0.25 % in the full width and half maximum for 5.486 MeV of 241Am.

  13. Optical properties of mesoporous 4H-SiC prepared by anodic electrochemical etching

    NASA Astrophysics Data System (ADS)

    Rashid, Marzaini; Horrocks, B. R.; Healy, N.; Goss, J. P.; Horsfall, A. B.

    2016-11-01

    Porous silicon carbide was fabricated from n-type 4H-SiC substrates via anodic electrochemical etching in HF/ethanol solution and suspended in ethanol after ultrasonication. We observed three photoluminescence bands: two at wavelengths of 303 nm and 345 nm were above the bulk bandgap and one at 455 nm was below the bulk bandgap. These blue-shifted and red-shifted emission processes reveal the interplay between quantum confinement, surface states, and band edge related optical transitions. We propose a model to explain the frequently observed deviation from the quantum confinement in the photoluminesence trends for SiC-derived nanoparticles suspended in solvents. The quantum confined properties of the SiC structures provide a route for optical tunability in the UV-blue spectrum for use in novel photonic and biomedical applications.

  14. NaBH4/H2O2 Fuel Cells for Lunar and Mars Exploration

    NASA Astrophysics Data System (ADS)

    Luo, Nie; Miley, George H.; Mather, Joseph; Burton, Rodney; Hawkins, Glenn; Gimlin, Richard; Rusek, John; Valdez, Tom I.; Narayanan, Sekharipuram R.

    2006-01-01

    The properties of direct hydrogen peroxide (H2O2) fuel cells are studied in this research. Different catalysts and diffusion electrodes are tested to optimize the cell performance. Initial results indicate: 1) conversion efficiency over 60% at a practical current density of 250mA/cm2; 2) power density over 0.6 W/cm2, at room temperature and ambient pressure, better than that of any traditional fuel cell. Further, the unique combination of NaBH4 and H2O2, both of which are in an aqueous form, paves the way for a convenient unitized regeneration, which is inherently compact compared to other cells that use gas phase reactants, such as the conventional H2 and O2. These excellent properties make the NaBH4/H2O2 fuel cell a very promising candidate for future space power systems. A conceptual design to power Lunar and Mars missions is discussed.

  15. Evidence for near-infrared photoluminescence of nitrogen vacancy centers in 4 H -SiC

    NASA Astrophysics Data System (ADS)

    Zargaleh, S. A.; Eble, B.; Hameau, S.; Cantin, J.-L.; Legrand, L.; Bernard, M.; Margaillan, F.; Lauret, J.-S.; Roch, J.-F.; von Bardeleben, H. J.; Rauls, E.; Gerstmann, U.; Treussart, F.

    2016-08-01

    We present evidence of near-infrared photoluminescence (PL) signature of nitrogen vacancy centers (NCVSi) - in silicon carbide (SiC). This center exhibits an S =1 ground state spin similar to the NV- center in diamond. We have performed photoluminescence excitation measurements at cryogenic temperature and demonstrated efficient photoexcitation of distinct photoluminescence from (NCVSi)- in 4 H -SiC. Furthermore, by correlating the energies of measured zero phonon lines (ZPLs) with theoretical values derived from hybrid density functional theory each of the ZPLs has been associated to the respective occupation of hexagonal (h ) and quasicubic (k ) lattice sites in close analogy to neutral divacancy centers (VCVSi) 0 in the same material. Finally, with the appropriate choice of excitation energy we demonstrated the selective excitation of (NCVSi) - PL with no contamination by (VCVSi) 0 PL, thereby opening the way towards the optical detection of (NCVSi) - electron spin resonance.

  16. Nitrogen-related point defect in 4H and 6H SiC

    NASA Astrophysics Data System (ADS)

    Zvanut, M. E.; van Tol, J.

    2007-12-01

    A nitrogen-related pair defect is studied as a function of doping density in 4H and 6H SiC. Electron paramagnetic resonance measurements verify that one nucleus in the pair is nitrogen, but the second part of the pair remains uncertain. The pair concentration varies monotonically with nitrogen concentration in samples with doping density 10 18-10 16 cm -3 and the boron concentration is an order of magnitude less than that of nitrogen. The pair center is not observed in the dark or under ultraviolet illumination when the nitrogen and boron concentrations are similar. We conclude that the pair is generated in all nitrogen-doped samples, but like the isolated nitrogen impurity, may be compensated by boron.

  17. Observations of deep levels in 4H-SiC using optoelectronic modulation spectroscopy

    NASA Astrophysics Data System (ADS)

    Chiu, Chi-Hsin; Parmiter, P. J. M.; Hilton, K.; Uren, M. J.; Swanson, J. G.

    2001-10-01

    Optoelectronic modulation spectroscopy (OEMS) has been used to reveal defect states in 4H-SiC. Pairs of magnitude and phase spectra have been used to infer whether they were electron or hole traps. Eleven discrete trap responses have been observed, eight were assigned as electron traps and three as hole traps. Five of these had been observed previously using optical admittance spectroscopy (OAS). An electron trap at 1.20 eV gave the most prominent response with a distinctive signature indicating that these traps were spatially delocalized with an extent of at least 1.35 nm, possibly associated with an extended defect structure. An unresolved continuum of be the superimposed response of an electron and hole trap at closely similar energies. Cosistency has been demonstrated with previous work using DLOS and OAS.

  18. Irradiation of 4H-SiC UV detectors with heavy ions

    SciTech Connect

    Kalinina, E. V. Lebedev, A. A.; Bogdanova, E.; Berenquier, B.; Ottaviani, L.; Violina, G. N.; Skuratov, V. A.

    2015-04-15

    Ultraviolet (UV) photodetectors based on Schottky barriers to 4H-SiC are formed on lightly doped n-type epitaxial layers grown by the chemical vapor deposition method on commercial substrates. The diode structures are irradiated at 25°C by 167-MeV Xe ions with a mass of 131 amu at a fluence of 6 × 10{sup 9} cm{sup −2}. Comparative studies of the optical and electrical properties of as-grown and irradiated structures with Schottky barriers are carried out in the temperature range 23–180°C. The specific features of changes in the photosensitivity and electrical characteristics of the detector structures are accounted for by the capture of photogenerated carriers into traps formed due to fluctuations of the conduction-band bottom and valence-band top, with subsequent thermal dissociation.

  19. Livestock-Associated MRSA Carriage in Patients without Direct Contact with Livestock

    PubMed Central

    van Rijen, Miranda M. L.; Bosch, Thijs; Verkade, Erwin J. M.; Schouls, Leo; Kluytmans, Jan A. J. W.

    2014-01-01

    Background Livestock-associated MRSA (MC398) has emerged and is related to an extensive reservoir in pigs and veal calves. Individuals with direct contact with these animals and their family members are known to have high MC398 carriage rates. Until now it was assumed that MC398 does not spread to individuals in the community without pig or veal calf exposure. To test this, we identified the proportion of MC398 in MRSA positive individuals without contact with pigs/veal calves or other known risk factors (MRSA of unknown origin; MUO). Methods In 17 participating hospitals, we determined during two years the occurrence of MC398 in individuals without direct contact with livestock and no other known risk factor (n = 271) and tested in a post analysis the hypothesis whether hospitals in pig-dense areas have higher proportions of MC398 of all MUO. Results Fifty-six individuals (20.7%) without animal contact carried MC398. In hospitals with high pig-densities in the adherence area, the proportion of MC398 of all MUO was higher than this proportion in hospitals without pigs in the surroundings. Conclusions One fifth of the individuals carrying MUO carried MC398. So, MC398 is found in individuals without contact to pigs or veal calves. The way of transmission from the animal reservoir to these individuals is unclear, probably by human-to-human transmission or by exposure to the surroundings of the stables. Further research is needed to investigate the way of transmission. PMID:25000521

  20. Mass spectrum of the butadiynyl radical (C4H; X2[summation operator]+)

    NASA Astrophysics Data System (ADS)

    Gu, Xibin; Guo, Ying; Kaiser, Ralf I.

    2005-11-01

    We utilized the crossed molecular beams method to synthesize the butadiynyl radical, C4H(X2[summation operator]+), via the reaction of dicarbon molecules with acetylene, under single collision conditions. Time-of-flight spectra of the radical were recorded at the center-of-mass angle (31°) of the parent ion (m/z = 49; C4H+) and of the fragments at m/z = 48 (C4+), m/z = 37 (C3H+), and m/z = 36 (C3+) This yields relative intensity ratios of I(m/z = 49):I(m/z = 48):I(m/z = 37):I(m/z = 36):I(m/z = 25):I(m/z = 24) = 1.0:0.67 +/- 0.07:0.47 +/- 0.06:0.2 +/- 0.02:0.08 +/- 0.02:0.04 +/- 0.02 at 70 eV electron impact energy. Signal at m/z = 13 (CH+) and 12 (C+) contribute less than 0.04 relative to the parent peak; the intensity of the 13C isotopic peak of the butadiynyl radical at m/z = 50 (13C12C3H+) depicts an intensity of 0.04 +/- 0.01 relative to m/z = 49. Employing linear scaling methods, the absolute ionization cross section of the butadiynyl radical was computed to be 8.8 +/- 1.8 × 10-16 cm2. These data can be employed in future space missions to detect the butadiynyl radical in oxygen-poor combustion flames and in the atmospheres of planets (Jupiter, Saturn, Uranus, Neptune and Pluto) and their moons (Titan, Triton and Oberon) in situ via matrix interval arithmetic assisted mass spectrometry.

  1. Picosecond pulsed laser ablation and micromachining of 4H-SiC wafers

    NASA Astrophysics Data System (ADS)

    Molian, Pal; Pecholt, Ben; Gupta, Saurabh

    2009-02-01

    Ultra-short pulsed laser ablation and micromachining of n-type, 4H-SiC wafer was performed using a 1552 nm wavelength, 2 ps pulse, 5 μJ pulse energy erbium-doped fiber laser with an objective of rapid etching of diaphragms for pressure sensors. Ablation rate, studied as a function of energy fluence, reached a maximum of 20 nm per pulse at 10 mJ/cm 2, which is much higher than that achievable by the femtosecond laser for the equivalent energy fluence. Ablation threshold was determined as 2 mJ/cm 2. Scanning electron microscope images supported the Coulomb explosion (CE) mechanism by revealing very fine particulates, smooth surfaces and absence of thermal effects including melt layer formation. It is hypothesized that defect-activated absorption and multiphoton absorption mechanisms gave rise to a charge density in the surface layers required for CE and enabled material expulsion in the form of nanoparticles. Trenches and holes micromachined by the picosecond laser exhibited clean and smooth edges and non-thermal ablation mode for pulse repetition rates less than 250 kHz. However carbonaceous material and recast layer were noted in the machined region when the pulse repetition rate was increased 500 kHz that could be attributed to the interaction between air plasma and micro/nanoparticles. A comparison with femtosecond pulsed lasers shows the promise that picosecond lasers are more efficient and cost effective tools for creating sensor diaphragms and via holes in 4H-SiC.

  2. Electrical and optical characterization of 4H-SiC diodes for particle detection

    NASA Astrophysics Data System (ADS)

    Schifano, Ramón; Vinattieri, Anna; Bruzzi, Mara; Miglio, Stefania; Lagomarsino, Stefano; Sciortino, Silvio; Nava, Filippo

    2005-05-01

    The electronic and optical properties of several (medium to high quality) 4H-SiC epitaxial sensors for particle detection have been studied. The samples are n-doped Schottky diodes with different nitrogen concentrations (6×1013cm-3-5×1015cm-3) and thicknesses (20-40μm). A full electrical and optical characterization has been performed by capacitance versus voltage measurements and near-band-edge low-temperature photoluminescence. The effective doping along the epilayer and the depletion width have been determined and data are consistent with the charge collection efficiency characterization performed with a minimum ionizing β-source. All the investigated samples exhibit a 100% collection efficiency. In particular, the best samples yield a highly reproducible signal, well separated from the pedestal. Photoluminescence results show a linear relationship between the effective doping and the ratio of nitrogen-bound excitonic emission (Q0) and free excitonic line (I76), in agreement with a previous work on 4H-SiC with a higher doping concentration [I. G. Ivanov, C. Hallin, A. Henry, O. Kordina, and E. Janzén, J. Appl. Phys. 80, 3504 (1996)]. Moreover we show that the dependence of the major spectral features as a function of the penetration depth of the exciting laser beam can quantitatively provide information on substrate contribution to the photoluminescence. In conclusion, we bring evidence that a detailed characterization of SiC-based detectors, by all optical techniques, yields an accurate value for the net doping and gives a qualitative information on the epilayer thickness prior to any electrical wafer tests.

  3. Electrical and optical characterization of 4H-SiC diodes for particle detection

    SciTech Connect

    Schifano, Ramon; Vinattieri, Anna; Bruzzi, Mara; Miglio, Stefania; Lagomarsino, Stefano; Sciortino, Silvio; Nava, Filippo

    2005-05-15

    The electronic and optical properties of several (medium to high quality) 4H-SiC epitaxial sensors for particle detection have been studied. The samples are n-doped Schottky diodes with different nitrogen concentrations (6x10{sup 13} cm{sup -3}-5x10{sup 15} cm{sup -3}) and thicknesses (20-40 {mu}m). A full electrical and optical characterization has been performed by capacitance versus voltage measurements and near-band-edge low-temperature photoluminescence. The effective doping along the epilayer and the depletion width have been determined and data are consistent with the charge collection efficiency characterization performed with a minimum ionizing {beta}-source. All the investigated samples exhibit a 100% collection efficiency. In particular, the best samples yield a highly reproducible signal, well separated from the pedestal. Photoluminescence results show a linear relationship between the effective doping and the ratio of nitrogen-bound excitonic emission (Q{sub 0}) and free excitonic line (I{sub 76}), in agreement with a previous work on 4H-SiC with a higher doping concentration [I. G. Ivanov, C. Hallin, A. Henry, O. Kordina, and E. Janzen, J. Appl. Phys. 80, 3504 (1996)]. Moreover we show that the dependence of the major spectral features as a function of the penetration depth of the exciting laser beam can quantitatively provide information on substrate contribution to the photoluminescence. In conclusion, we bring evidence that a detailed characterization of SiC-based detectors, by all optical techniques, yields an accurate value for the net doping and gives a qualitative information on the epilayer thickness prior to any electrical wafer tests.

  4. Hydride CVD Hetero-epitaxy of B12P2 on 4H-SiC

    NASA Astrophysics Data System (ADS)

    Frye, C. D.; Saw, C. K.; Padavala, Balabalaji; Nikolić, R. J.; Edgar, J. H.

    2017-02-01

    Icosahedral boron phosphide (B12P2) is a wide bandgap semiconductor (3.35 eV) that has been reported to "self-heal" from high-energy electron bombardment, making it attractive for potential use in radioisotope batteries, radiation detection, or in electronics in high radiation environments. This study focused on improving B12P2 hetero-epitaxial films by growing on 4H-SiC substrates over the temperature range of 1250-1450 °C using B2H6 and PH3 precursors in a H2 carrier gas. XRD scans and Laue transmission photographs revealed that the epitaxial relationship was (0001)< 11 2 bar 0 > B12P2 ∥ (0001)< 11 2 bar 0 > 4 H - SiC . The film morphology and crystallinity were investigated as a function of growth temperature and growth time. At 1250 °C, films tended to form rough, polycrystalline layers, but at 1300 and 1350 °C, films were continuous and comparatively smooth (RRMS ≤ 7 nm). At 1400 or 1450 °C, the films grew in islands that coalesced as the films became thicker. Using XRD rocking curves to evaluate the crystal quality, 1300 °C was the optimum growth temperature tested. At 1300 °C, the rocking curve FWHM decreased with increasing film thickness from 1494 arcsec for a 1.1 μm thick film to 954 arcsec for a 2.7 μm thick film, suggesting a reduction in defects with thickness.

  5. Device design assessment of 4H-SiC n-IGBT - A simulation study

    NASA Astrophysics Data System (ADS)

    Usman, Muhammad; Nawaz, Muhammad

    2014-02-01

    A theoretical design assessment is presented using two dimensional numerical computer aided design (TCAD) tool for 15-20 kV 4H-SiC IGBTs. Physical parameters of the layer structures such as drift layer thickness, doping in the drift layer, JFET region width and interface charges underneath the gate region are varied to predict the device performance. Performance is further assessed at different temperatures and with different carrier lifetime in the drift layer. Using identical set of physical device parameters (doping, thicknesses), simulated structure was first calibrated with the experimental data. Simulations show that a minority carrier lifetime in the drift layer of 1.0-1.6 μs produces a close match with the experimental device. An on-resistance first decays with temperature (i.e., increased in ionization level, and increase in minority carrier lifetime), stays nearly constant with further increase in the temperature (may be all carriers are now fully ionized and increase in carrier lifetime is compensated with decrease in the carrier mobility) and finally increases linearly with temperature (>450 K) due to decrease in the carrier mobility. A significant increase in the forward voltage drop is observed with the presence of interface trap charges. Increasing JFET region width slightly decreases the forward on-state voltage. A drift layer of at least 175 μm thick with a doping concentration of < 2.0 × 1014 cm-3 is required to get a blocking voltage of 20 kV for 4H-SiC IGBTs assuming a minority carrier lifetime of 1 μs in the drift layer.

  6. Mitigating climate change: the role of domestic livestock.

    PubMed

    Gill, M; Smith, P; Wilkinson, J M

    2010-03-01

    Livestock contribute directly (i.e. as methane and nitrous oxide (N2O)) to about 9% of global anthropogenic greenhouse gas (GHG) emissions and around 3% of UK emissions. If all parts of the livestock production lifecycle are included (fossil fuels used to produce mineral fertilizers used in feed production and N2O emissions from fertilizer use; methane release from the breakdown of fertilizers and from animal manure; land-use changes for feed production and for grazing; land degradation; fossil fuel use during feed and animal production; fossil fuel use in production and transport of processed and refrigerated animal products), livestock are estimated to account for 18% of global anthropogenic emissions, but less than 8% in the UK. In terms of GHG emissions per unit of livestock product, monogastric livestock are more efficient than ruminants; thus in the UK, while sheep and cattle accounted for 32% of meat production in 2006, they accounted for 48% of GHG emissions associated with meat production. More efficient management of grazing lands and of manure can have a direct impact in decreasing emissions. Improving efficiency of livestock production through better breeding, health interventions or improving fertility can also decrease GHG emissions through decreasing the number of livestock required per unit product. Increasing the energy density of the diet has a dual effect, decreasing both direct emissions and the numbers of livestock per unit product, but, as the demands for food increase in response to increasing human population and a better diet in some developing countries, there is increasing competition for land for food v. energy-dense feed crops. Recalculating efficiencies of energy and protein production on the basis of human-edible food produced per unit of human-edible feed consumed gave higher efficiencies for ruminants than for monogastric animals. The policy community thus have difficult decisions to make in balancing the negative contribution of

  7. Charcot-Marie-Tooth Disease Type 4H Resulting from Compound Heterozygous Mutations in FGD4 from Nonconsanguineous Korean Families.

    PubMed

    Hyun, Young Se; Lee, Jinho; Kim, Hye Jin; Hong, Young Bin; Koo, Heasoo; Smith, Alec S T; Kim, Deok-Ho; Choi, Byung-Ok; Chung, Ki Wha

    2015-11-01

    Charcot-Marie-Tooth disease type 4H (CMT4H) is an autosomal recessive demyelinating subtype of peripheral enuropathies caused by mutations in the FGD4 gene. Most CMT4H patients are in consanguineous Mediterranean families characterized by early onset and slow progression. We identified two CMT4H patients from a Korean CMT cohort, and performed a detailed genetic and clinical analysis in both cases. Both patients from nonconsanguineous families showed characteristic clinical manifestations of CMT4H including early onset, scoliosis, areflexia, and slow disease progression. Exome sequencing revealed novel compound heterozygous mutations in FGD4 as the underlying cause in both families (p.Arg468Gln and c.1512-2A>C in FC73, p.Met345Thr and c.2043+1G>A (p.Trp663Trpfs*30) in FC646). The missense mutations were located in highly conserved RhoGEF and PH domains which were predicted to be pathogenic in nature by in silico modeling. The CMT4H occurrence frequency was calculated to 0.7% in the Korean demyelinating CMT patients. This study is the first report of CMT4H in Korea. FGD4 assay could be considered as a means of molecular diagnosis for sporadic cases of demyelinating CMT with slow progression.

  8. Measurement of Optical, Mechanical and Transport properties of the hexagonal closed packed 4H polytype of metallic silver

    NASA Astrophysics Data System (ADS)

    Chakraborty, Indrani; Shirodkar, Sharmila N.; Gohil, Smita; Waghmare, Umesh; Ayyub, Pushan

    2013-03-01

    Optical, mechanical and transport property measurements were done on the hexagonal closed packed (hcp) 4H polytype of Ag with stacking sequence ABCBABCB.. grown as bulk films on Al2O3 substrates. Diffused reflectance measurements done on the 4H films showed a general loss of reflectivity amounting to a decrease of 35% as compared to normal fcc (3C) Ag near 500 nm with a blueshift of 5nm in the bulk plasmon frequency, possibly due to the modified electronic structure of the hcp form. Raman spectroscopic measurements showed the appearance of a peak at 64.3 cm-1 at 4K which underwent ``Mode softening,'' that is shifted to lower wave numbers with increase of temperature and disappeared above 350K. Low temperature transport measurements done on 4H films gave the in-plane resistivity value to be 39 times higher than that of a similarly synthesized fcc Ag film at 295 K. Vicker's microhardness measurements done on the 4H films showed that the 4H samples to be almost 5 times harder than the 3C Ag. Density functional theory simulations were done to obtain the phonon dispersion, band structure and nature of Fermi surface for the 4H Ag which corroborated with the experimental observations. The 4H form appears to be a much less metallic, darker and harder form of Ag.

  9. A plan for the handling of externally contaminated livestock.

    PubMed

    McMillan, Dayton; Johnson, Thomas; Guo, Yuanqing; Brandl, Alexander

    2011-11-01

    Nuclear accidents and access to radiological weapons for terrorist organizations and countries with hostile intentions towards the United States are realistic scenarios in the current global landscape. A dispersion of radionuclides can result from a nuclear weapon detonation or from a nuclear accident occurring in facilities handling or using radioactive material, such as nuclear power reactors. Any target of a radiological dispersal device (RDD) or an attack with a nuclear weapon and the surrounding area of a reactor accident could be subject to a significant amount of fallout and radioactive contamination. Therefore, a nuclear event in close proximity to agricultural areas will cause significant concern regarding the contamination of food products. In order to respond quickly and effectively to a large amount of contaminated agricultural products, such as livestock, a prepared and effective plan for handling and processing of these products is necessary. A protocol outlining the evaluation of and procedures for handling and processing radioactively contaminated livestock is proposed, to ensure safe animal food production and economic stability in the livestock industry in the wake of such a nuclear or radiological event. An evaluation of the salvageability of the contaminated livestock is performed based on the degree of exposure, the cost of decontamination, expected demand for food products, and economic impact to the owner/producer. Important factors that impact the salvageability of affected livestock are listed and analyzed to support the decision process for handling contaminated animals.

  10. Prevalence of hydatid cysts in livestock animals in Xinjiang, China.

    PubMed

    Qingling, Meng; Guanglei, Wang; Jun, Qiao; Xinquan, Zhu; Tianli, Liu; Xuemei, Song; Jinsheng, Zhang; Huisheng, Wang; Kuojun, Cai; Chuangfu, Chen

    2014-06-01

    Hydatid worms, hosted by humans and animals, impose serious human health risk and cause significant livestock production loss. To better understand the disease infection status in Xinjiang, China, we investigated the disease epidemics in 4 livestock animals, i.e., cattle, sheep (both sheep and goat), camels, and horses, slaughtered at the abattoirs in Urumqi, Yining, Tacheng, and Altay areas. The results showed that the animals were infected at different rates, in the order of sheep (9.8%), cattle (8.4%), camels (6.8%), and horses (4.3%). The infection rates were found to be different between the abattoirs in various regions even for the same animals. For sheep, the rates increased significantly as the animals grew older. It was 1.9% before 1 year of age and increased to 8.2% in the age of 1-2 years, and further increased to 12.3% when the animals were 3-4 years old, and reached 17.2% when they were 5-6 year old. Sheep older than 6 years had an infection rate of 19.5%. This study demonstrates that the 4 livestock animals in the pastoral areas in Xinjiang were infected by the parasites to various extend. This study is the first systematic investigation of the hydatid worms in various livestock animals in Xinjiang, China, which provides epidemiological information about the infection of hydatid worms in livestock, and is valuable in developing strategies for prevention and control of the hydatid disease.

  11. Organic livestock production in Uganda: potentials, challenges and prospects.

    PubMed

    Nalubwama, Sylvia Muwanga; Mugisha, Anthony; Vaarst, Mette

    2011-04-01

    Development in organic farming has been stimulated by farmers and consumers becoming interested in healthy food products and sustainable environment. Organic agriculture is a holistic production management system which is based on the principles of health, ecology, care, and fairness. Organic development in Uganda has focused more on the crop sector than livestock sector and has primarily involved the private sector, like organic products export companies and non-governmental organizations. Agriculture in Uganda and many African countries is predominantly traditional, less mechanized, and is usually associated with minimum use of chemical fertilizers, pesticides, and drugs. This low external input agriculture also referred to as "organic by default" can create basis for organic farming where agroecological methods are introduced and present an alternative in terms of intensification to the current low-input/low-output systems. Traditional farming should not be confused with organic farming because in some cases, the existing traditional practices have consequences like overstocking and less attention to soil improvement as well as to animal health and welfare, which is contrary to organic principles of ecology, fairness, health, and care. Challenges of implementing sustainable organic practices in the Ugandan livestock sector threaten its future development, such as vectors and vector-borne diseases, organic feed insufficiency, limited education, research, and support to organic livestock production. The prospects of organic livestock development in Uganda can be enhanced with more scientific research in organic livestock production under local conditions and strengthening institutional support.

  12. Ischaemic heart disease among livestock and agricultural workers

    PubMed Central

    Sjogren, B; Weiner, J; Larsson, K

    2003-01-01

    Aims: To compare the occurrence of ischaemic heart disease (IHD) among male and female livestock and agricultural workers with gainfully employed men and women in Sweden. Methods: Male and female livestock and agricultural workers were identified in the Swedish National Censuses of 1970 and 1990 and were followed until the end of 1995. The IHD mortality among the livestock and agricultural workers was compared with that of gainfully employed men and women. Information of smoking habits was gathered from a previous national survey. Results: Male as well as female livestock workers had slightly higher standardised mortality ratios (SMR) regarding IHD compared with all gainfully employed men and women in Sweden. The SMR for male workers was 1.06 (95% CI 0.95 to 1.18). The SMR for female workers was 1.10 (95% CI 0.98 to 1.23). Agricultural workers had lower SMRs. Adjustments for smoking habits would further increase the SMRs by about 9% in male workers and about 5% in female workers. Conclusion: The present data suggest a slightly increased risk for IHD among both male and female livestock workers, which may be the result of organic dust exposure. PMID:12883028

  13. Electronic spectrum and photodissociation chemistry of the linear methyl propargyl cation H2C4H3+

    NASA Astrophysics Data System (ADS)

    Catani, Katherine J.; Muller, Giel; da Silva, Gabriel; Bieske, Evan J.

    2017-01-01

    The electronic spectrum of the methyl propargyl cation (2-butyn-1-yl cation, H2C4H3+) is measured over the 230-270 nm range by photodissociating the bare cation and its Ar and N2 tagged complexes in a tandem mass spectrometer. The observed '1A←'1A band system has an origin at 37 753 cm-1 for H2C4H3+ , 37738 cm-1 for H2C4H3+ - Ar, and 37 658 cm-1 for H2C4H3+ - N2. The methyl propargyl cation photodissociates to produce either C2H3++C2H2 (protonated acetylene + acetylene) or H2C4H+ +H2 (protonated diacetylene + dihydrogen). Photodissociation spectra of H2C4H3+ , H2C4H3+ - Ar, and H2C4H3+ - N2 exhibit similar vibronic structure, with a strong progression of spacing 630 cm-1 corresponding to excitation of the C—C stretch mode. Interpretation of the spectra is aided by ground and excited state calculations using time dependent density functional theory at the ωB97X-D/aug-cc-pVDZ level of theory. Ab initio calculations and master equation simulations were used to interpret the dissociation of H2C4H3+ on the ground state manifold. These calculations support the experimentally observed product branching ratios in which acetylene elimination dominates and also suggests that channel switching occurs at higher energies to favor H2 elimination.

  14. Connecting Kids To The Universe: Partnering With 4-H Youth Development To Pilot 'Afterschool Universe' In New York

    NASA Astrophysics Data System (ADS)

    Schaff, Nancy

    2008-05-01

    4-H Youth Development - as the youth program of the Cooperative Extension system associated with the land grant university in every state - is an ideal partner for statewide dissemination of EPO programs. With funding from a Chandra Cycle 9 EPO grant we are piloting `Afterschool Universe’ in five urban locations in New York State. `Afterschool Universe’ is an education/outreach effort sponsored by NASA's Beyond Einstein program and was developed in partnership with the Imagine the Universe EPO program. The program is targeted at middle school students in out-of-school-time settings and explores basic astronomy concepts focused on the Universe beyond the solar system. Consisting of 12 sessions of engaging hands-on activities, the flexibly structured program can be used in a variety of settings, including astronomy days, youth groups, summer camps, and afterschool programs. Partnering with 4-H Youth Development helps us reach large numbers of underserved and underrepresented minority youth and girls in widely dispersed areas of New York and fits ideally with the current national 4-H SET (science, engineering, and technology) initiative and emphasis on 4-H afterschool programming. The pilot program provides teaching kits and workshops for program leaders. Our 4-H county partners recruit afterschool program staff, science center staff, 4-H volunteers, 4-H teens, and other youth group leaders as workshop participants. The 4-H program will house and loan the kit to trained leaders. By providing kits and training in 2008, we are gearing up for International Year of Astronomy programs in 2009 in out-of-school settings. Based on pilot results, we will seek additional funding to expand the program. The poster will discuss kit development, 4-H partnership, workshops, participating organizations, target audiences, successes, and challenges.

  15. Long-term soil microbial community and enzyme activity responses to an integrated cropping-livestock system in a semi-arid region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water availability is a significant factor limiting agriculture in many semiarid or arid regions of the world. This study is part of a larger project to develop and evaluate integrated crop and livestock systems that reduce dependence on underground water while optimizing cotton (Gossypium hirsutum)...

  16. Long-term soil microbial community and enzyme activity responses to an integrated cropping-livestock system in a semi-arid region

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study is part of a larger long-term project to develop and evaluate integrated crop and livestock systems in order to reduce dependence on underground water sources by optimizing cotton (Gossypium hirsutum) production in the Texas High Plains of U.S. Microbial communities and activities were e...

  17. Implantation-Free 4H-SiC Bipolar Junction Transistors with Double Base Epi-layers

    DTIC Science & Technology

    2007-05-14

    gain 4H-SiC NPN power bipolar junction transistor ,” IEEE Electron Device Letters, vol. 24, pp. 327-329, May 2003. [3] C.-F. Huang and J. A. Cooper...Jr., “High current gain 4H-SiC NPN Bipolar Junction Transistors ,” IEEE Electron Device Letters, vol. 24, pp. 396-398, Jun. 2003. [4] Sumi...Implantation-Free 4H-SiC Bipolar Junction Transistors with Double Base Epi-layers Jianhui Zhang, member, IEEE, Xueqing, Li, Petre Alexandrov

  18. The Impact of Stakeholders’ Roles within the Livestock Industry on Their Attitudes to Livestock Welfare in Southeast and East Asia

    PubMed Central

    Sinclair, Michelle; Zito, Sarah; Phillips, Clive J. C.

    2017-01-01

    Simple Summary Improving stakeholder attitudes to livestock welfare may help to facilitate the better welfare that is increasingly demanded by the public for livestock. Knowledge of the existing attitudes towards the welfare of livestock during transport and slaughter provides a starting point that may help to target efforts. We compared the attitudes of different stakeholders within the livestock industries in east (E) and southeast (SE) Asia. Farmers were more motivated to improve animal welfare during transport and slaughter by peer pressure, business owners by monetary gain, and business managers by what is prescribed by their company. Veterinarians showed the most support for improving animal welfare. The results suggest that the role that stakeholders play in their sector of the livestock industry must be considered when attempting to change attitudes towards animal welfare during transport and slaughter. Abstract Stakeholders in the livestock industry are in a position to make critical choices that directly impact on animal welfare during slaughter and transport. Understanding the attitudes of stakeholders in livestock-importing countries, including factors that motivate the stakeholders to improve animal welfare, can lead to improved trade relations with exporting developed countries and improved animal welfare initiatives in the importing countries. Improving stakeholder attitudes to livestock welfare may help to facilitate the better welfare that is increasingly demanded by the public for livestock. Knowledge of the existing attitudes towards the welfare of livestock during transport and slaughter provides a starting point that may help to target efforts. This study aimed to investigate the animal welfare attitudes of livestock stakeholders (farmers, team leaders, veterinarians, business owners, business managers, and those working directly with animals) in selected countries in E and SE Asia (China, Thailand, Viet Nam, and Malaysia). The factors that

  19. Improving animal health and livestock productivity to reduce poverty.

    PubMed

    Pradère, J-P

    2014-12-01

    This study is based on scientific publications, statistics and field observations. It shows the importance of livestock in the economy and in the risk management strategies implemented by poor farming households. A comparison of livestock performance trends with the evolution of rural poverty in developing countries indicates that growth in livestock production alone is not enough to reduce rural poverty. To help reduce poverty, sustainable production should be based on productivity gains. Prerequisites for improving productivity include better public policies, enhanced research and the reduction of animal disease risk. The study draws attention to the economic, social and environmental consequences of inadequate support for animal health and production in the least developed countries, especially those of sub-Saharan Africa.

  20. Wildfire: It's Economic Impact on Grazing Livestock in Northern Nevada

    NASA Astrophysics Data System (ADS)

    Honeycutt, S.

    2015-12-01

    As the climate changes and Nevada experiences long severe drought, a key understanding of the economic impacts of wildfire on grazing livestock is essential in the assurance of livestock production in future management of Nevada's rangeland. The focus of this research is to determine the economic impact in the reduction of rangeland available for livestock grazing due to wildfires. The datasets utilized in this research are from 2007 & 2012 and include Bureau of Land Management wildfire, grazing allotments and herd management area geospatial data along with USDA Census of Agriculture, Inventory & Sales Information for cattle & calves, sheep & lambs, and goats. Presented in the results will be the direct, indirect, and induced economic effects of wildfires on rangeland production.