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2000

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Articles 1891 - 1920 of 2418

Full-Text Articles in Life Sciences

Agro-Socio-Economic Evaluation Of Three Rural Communities In The Colta Canton Of The Chimborazo Province, Ivan Asaquibay Paucar Jan 2000

Agro-Socio-Economic Evaluation Of Three Rural Communities In The Colta Canton Of The Chimborazo Province, Ivan Asaquibay Paucar

Theses and Dissertations

The faculty of natural resources, School of Agricultural Engineering of ESPOCH, with an agreement since 1992 with the Benson Institute of Brigham Young University has been working with the development of small scale production before its diffusion it is necessary to know the real social- economic conditions and the technological levels of the most important harvests of the communities, that when this model is involved in the aspects that affect the production. For this reason this investigation was made necessary in which the following objectives were raised: 1. Evaluate the social-economic conditions of the communities of San Lorenzo of Cahuiña, …


Application Of Dietary Guidelines For Guatemala In Three Rural Communities Of Chiquimula, Sandra Liseth Salazar Donis Jan 2000

Application Of Dietary Guidelines For Guatemala In Three Rural Communities Of Chiquimula, Sandra Liseth Salazar Donis

Theses and Dissertations

In Guatemala, nutritional problems are directly related to the difficulty to purchase food fit for human consumption due to low family incomes as well as low nutritional education. This situation motivated the realization of the present study whose main objective was to apply the dietary guidelines for Guatemala in three rural communities of Chiquimula. All three communities were previously aided by Benson Institute efforts to promote changes in eating behavior. The sample was comprised of mothers from the El Pinalito, El Guayabo, and Maraxco communities of the department of Chiquimula. There were eight mothers, four literate and four illiterate, from …


Knowledge, Attitudes And Practices Concerning Alimentary Customs And Beliefs Of Women With Children Younger Than 5 Years Old, Nursing And Pregnant Mothers, Of The Following Ethnic Groups: Black, Mixed Race And Natives In Three Rural Regions Of The Imbabura Province, 1998-1999, Elva Susana Yacelga Calderon Jan 2000

Knowledge, Attitudes And Practices Concerning Alimentary Customs And Beliefs Of Women With Children Younger Than 5 Years Old, Nursing And Pregnant Mothers, Of The Following Ethnic Groups: Black, Mixed Race And Natives In Three Rural Regions Of The Imbabura Province, 1998-1999, Elva Susana Yacelga Calderon

Theses and Dissertations

Ecuador, a country of multi-ethnic culture, has very acute health problems, especially in rural areas where two out of every three poverty-stricken Ecuadorians live. 77% of the population under 18 years of age is under the poverty level. The greater part of the indigenous population inhabits the rural areas of the Andes and the Amazon. 76% of children in the rural Andes are poor. Little Afro-Ecuadorian boys and girls also face severe disadvantages where, in the rural areas, poverty climbs above 70% of the population under 18 years of age. Academic desertion is another factor that affects especially the young …


An Integrated Science Unit : Ants, Julia Dillehay Jan 2000

An Integrated Science Unit : Ants, Julia Dillehay

Graduate Research Papers

This instructional development project integrated language arts and the science areas. A print-rich environment extended content and offered models of language, thus energizing children to become actively involved in the study. Many literature genres and.related expressive activities provided children with many options for learning experiences. The focus for this science unit for grade two was on ants. A print-rich environment was provided along with computer software and access to information on the internet.


Dietary Phosphorus Effects On Waste Management And Nutrient Balance In The Feedlot, Galen E. Erickson, Terry J. Klopfenstein, Todd Milton, Daniel T. Walters Jan 2000

Dietary Phosphorus Effects On Waste Management And Nutrient Balance In The Feedlot, Galen E. Erickson, Terry J. Klopfenstein, Todd Milton, Daniel T. Walters

Nebraska Beef Cattle Reports

Four experiments were conducted, two with calves in the winter/spring and two with yearlings during the summer, to evaluate the effects of decreasing dietary phosphorus on nutrient balance in the feedlot. The control diets averaged .38% phosphorus, whereas the experimental diets were formulated to not exceed requirements (~.25%). Phosphorus excretion was reduced by feeding the lower phosphorus diet. Phosphorus removed in manure at cleaning was not different. However, when manure was corrected for soil phosphorus, phosphorus removal was decreased by 59% in the summer trials and 38% in the calf trials during the winter/spring by feeding the experimental diet.


Effect Of Increasing Dietary Corn Silage On Performance, Digestibility And Nitrogen Mass Balance In The Feedlot, Galen E. Erickson, Terry J. Klopfenstein, Todd Milton, Ryan Mass Jan 2000

Effect Of Increasing Dietary Corn Silage On Performance, Digestibility And Nitrogen Mass Balance In The Feedlot, Galen E. Erickson, Terry J. Klopfenstein, Todd Milton, Ryan Mass

Nebraska Beef Cattle Reports

Three dietary corn silage levels (15, 30, and 45% of diet DM) were evaluated in corn finishing diets fed to calves through the winter/spring and yearlings during the summer to determine effects on performance and nitrogen mass balance in feedlot. Yearling gains decreased quadratically with increasing corn silage; however, N and OM removed in manure was greatest for the 30% silage treatment. Calf gains decreased linearly as silage increased; however, N and OM removed in manure was greatest for the 45% silage treatment. Increasing dietary corn silage resulted in decreased gains but did influence manure N with no effect on …


Adding Value To Low-Quality Beef Muscles Through Glycolytic Inhibition In Pre-Rigor Muscle, Nancy Jerez, Chris R. Calkins, Jesus Velazco Jan 2000

Adding Value To Low-Quality Beef Muscles Through Glycolytic Inhibition In Pre-Rigor Muscle, Nancy Jerez, Chris R. Calkins, Jesus Velazco

Nebraska Beef Cattle Reports

Pre-rigor Semimembranosus, Triceps brachii and Supraspinatus muscles were removed from 10 steers to determine effects of several glycolysis-inhibiting compounds on pH, tenderness and color. Muscles were injected and tumbled with 10% of sodium citrate, sodium fluoride, sodium acetate, or calcium chloride. Sodium citrate and sodium fluoride increased pH values in Semimembranosus, Triceps brachii and Supraspinatus. Tenderness improved in Triceps brachii and Supraspinatus with calcium chloride, sodium fluoride and sodium citrate when compared with controls. Color values were not different among treatments. Sodium citrate and sodium fluoride were successful in improving beef tenderness by maintaining a high pH in pre-rigor …


Exporting Feedlot Manure To Off-Farm Users, Richard K. Koelsch, Keith Glewen, Tom Trewhitt, Daniel T. Walters Jan 2000

Exporting Feedlot Manure To Off-Farm Users, Richard K. Koelsch, Keith Glewen, Tom Trewhitt, Daniel T. Walters

Nebraska Beef Cattle Reports

A survey of Nebraska feedlots suggests the majority of feedlots do not export manure to off-farm customers despite a common lack of land base (owned or managed by the feedlot) for using the nitrogen and phosphorus in manure. Only a small portion of the feedlots in Nebraska are actively marketing manure as a product with value by packaging agronomic and nuisance avoidance services with the manure in an effort to enhance its value. A separate survey of manure users suggests that the reason users purchase manure was for its crop nutrient value. However, many users were uncomfortable relying on the …


Feed Program Impact On Land Requirements For Managing Manure Nutrients From A Feedlot, Richard K. Koelsch Jan 2000

Feed Program Impact On Land Requirements For Managing Manure Nutrients From A Feedlot, Richard K. Koelsch

Nebraska Beef Cattle Reports

Using data from UNL feeding trials (1998 Nebraska Beef Report, pp. 86- 88) designed to compare the impact of protein and phosphorus intake on nutrient excretion, an estimate is made of the land requirement for manure application. A balanced diet formulated using the 1996 NRC was compared to other typical feed rations. The standard industry ration required an additional 100 and 400 acres of land to manage the additional manure nitrogen and phosphorus excreted, respectively, by a 1,000 head feedlot. A spreadsheet tool is introduced for estimating land requirements for manure produced by alternative feeding programs.


Growth Implants For Heifers, Terry L. Mader Jan 2000

Growth Implants For Heifers, Terry L. Mader

Nebraska Beef Cattle Reports

In a 110-d experiment, feedlot heifers (mean initial weight = 820 lb) that received an estradiol benzoate (EB) + trenbolone acetate (TBA) implant, Synovex® Plus™, gained faster and more efficiently than sham-implanted (control) heifers. Heifers that received only TBA implants had lower intakes and lower quality grades than control heifers, but were more efficient in feed conversion than control and EB implanted heifers. On the basis of improved yield grade and larger ribeye areas, along with no increases in fatness, the combined use of EB and TBA provided for greater quantities of lean meat from higher priced cuts than did …


Supplementing Metabolizable Protein To Yearling Heifers Grazing Winter Range, Trey Patterson, Don C. Adams, Terry J. Klopfenstein, Jacqueline A. Musgrave, Andy Applegarth Jan 2000

Supplementing Metabolizable Protein To Yearling Heifers Grazing Winter Range, Trey Patterson, Don C. Adams, Terry J. Klopfenstein, Jacqueline A. Musgrave, Andy Applegarth

Nebraska Beef Cattle Reports

Two experiments were conducted with pregnant yearling heifers grazing Sandhills winter range to evaluate response of supplementing to meet the metabolizable protein requirement of the heifers versus conventional supplementation based on crude protein. Supplements were fed from October to February (pre-calving) both years. Intake was measured in November, January and February of the first year. Supplementing to meet metabolizable protein requirement improved the heifers’ ability to maintain weight in year one, but not in year two. Heifer intakes ranged from 2.2% of BW in November to 1.5% in February. Feeding hay reduced body weight loss compared to no hay feeding …


Evaluation Of The 1996 Beef Cattle Nrc Model Predictions Of Intake And Gain For Calves Fed Low Or Medium Energy Density Diets, Trey Patterson, Terry J. Klopfenstein, Todd Milton, Dennis R. Brink Jan 2000

Evaluation Of The 1996 Beef Cattle Nrc Model Predictions Of Intake And Gain For Calves Fed Low Or Medium Energy Density Diets, Trey Patterson, Terry J. Klopfenstein, Todd Milton, Dennis R. Brink

Nebraska Beef Cattle Reports

Data from feeding 54 diets in seven previous beef cattle growing studies were used to evaluate the 1996 NRC model for the accuracy of intake and gain predictions. Calf weights and diets were inputs into the model, and actual intakes were used to calculate predicted gain and actual gains were used to calculate predicted intakes. The model over-predicted calf intakes on low quality diets and under-predicted intakes on high quality diets. The model over-predicted gains on high quality diets and under-predicted gains on low quality diets. The NRC model did not accurately predict performance of cattle on low quality roughage …


Humboldt Journal Of Microbiology: Volume 3, Number 1- May 2000, Press Humboldt Jan 2000

Humboldt Journal Of Microbiology: Volume 3, Number 1- May 2000, Press Humboldt

Humboldt Journal of Microbiology

No abstract provided.


Growth Curves Of Four Species Of Commercially Valuable Freshwater Mussels (Bivalva: Unionidae), Alan D. Christian, Chris L. Davidson, William R. Posey Ii, Peter J. Rust, Jerry L. Farris, John L. Harris, George L. Harp Jan 2000

Growth Curves Of Four Species Of Commercially Valuable Freshwater Mussels (Bivalva: Unionidae), Alan D. Christian, Chris L. Davidson, William R. Posey Ii, Peter J. Rust, Jerry L. Farris, John L. Harris, George L. Harp

Journal of the Arkansas Academy of Science

North American freshwater mussels (Bivalvia: Unionidae) have been exploited commercially for over 100 years and have been regulated using shell size limits and/or harvest seasons. Presently, freshwater mussels are considered a threatened faunal group in North America due to the large numbers of endangered, threatened or special concern species. Therefore, management of this fauna should emphasize their long-term sustainability. The objectives of this study were 1) to construct von Bertalanffy growth curves for selected "commercially-most-valuable" species, Fusconaia ebena, Megalonaias nervosa, Amblema plicata and Quadrula quadrula, from five rivers and two reservoirs, 2) to compare species-specific von Bertalanffy growth curves from …


Optical Transmittance Of A Rice Leaf Via Ray Tracing, Stephen Nicoletti, Alois (Al) J. Adams Jan 2000

Optical Transmittance Of A Rice Leaf Via Ray Tracing, Stephen Nicoletti, Alois (Al) J. Adams

Journal of the Arkansas Academy of Science

Optical reflectance from a plant leaf increases in response to stress and disease. Previous studies at the University of Arkansas at Little Rock found that, while the reflectance from a rice leaf increased with increased salinity, reflectance changes could not be used to differentiate one stress or disease from another. The objective of this study is to characterize the angular distribution of optical transmittance for a healthy rice leaf using a ray tracing technique and assuming a three-media optical model. The ultimate goal is to relate this distribution to specific plant pathologies. Three rays are traced through the cross section …


Method To Predict The Potential Regional Long-Term Timber Supply Using Gis And Other Publicly Available Data, Jeffery Earl, Richard A. Kluender, Robert Brewington Jan 2000

Method To Predict The Potential Regional Long-Term Timber Supply Using Gis And Other Publicly Available Data, Jeffery Earl, Richard A. Kluender, Robert Brewington

Journal of the Arkansas Academy of Science

While the global demand for wood products is on the rise, timber production has shifted from the Pacific Northwest to the southeastern United States in recent times. The increase in harvesting makes accurate assessment of the South's wood supply essential. Anew method is proposed for looking at the potential supply of raw woody material. The test area was three southeastern Arkansas counties. A geographic information system (GIS) using ArcView software incorporates two sources of public information. First, Forest Inventory and Analysis (FIA) data from the USDA Forest Service were queried to find land areas and volumes by timber type, as …


New Arkansas Records For Two Nonindigenous Fish Species, With A Summary Of Previous Introductions Of Nonnative Fishes In Arkansas, Thomas M. Buchanan, Jerry Smith, Diana Saul, Jeff Farwick, Tim Burnley, Mark Oliver, Ken Shirley Jan 2000

New Arkansas Records For Two Nonindigenous Fish Species, With A Summary Of Previous Introductions Of Nonnative Fishes In Arkansas, Thomas M. Buchanan, Jerry Smith, Diana Saul, Jeff Farwick, Tim Burnley, Mark Oliver, Ken Shirley

Journal of the Arkansas Academy of Science

No abstract provided.


Curly-Tail Malformity In Hatchlings Of The Alligator Snapping Turtle, Macroclemys Temminckii (Testudines: Chelydridae) In Arkansas, Malcolm L. Mccallum, Stanley E. Trauth Jan 2000

Curly-Tail Malformity In Hatchlings Of The Alligator Snapping Turtle, Macroclemys Temminckii (Testudines: Chelydridae) In Arkansas, Malcolm L. Mccallum, Stanley E. Trauth

Journal of the Arkansas Academy of Science

No abstract provided.


Breeding Mortality In The Wood Frog, Rana Sylvatica (Anura: Ranidae), From Northcentral Arkansas, Stanley E. Trauth, Malcolm L. Mccallum, Michael E. Cartwright Jan 2000

Breeding Mortality In The Wood Frog, Rana Sylvatica (Anura: Ranidae), From Northcentral Arkansas, Stanley E. Trauth, Malcolm L. Mccallum, Michael E. Cartwright

Journal of the Arkansas Academy of Science

No abstract provided.


Home Ranges And Movements Of Adult Deer On Fort Chaffee, Arkansas, Gregory G. Humphreys, Thomas A. Nelson Jan 2000

Home Ranges And Movements Of Adult Deer On Fort Chaffee, Arkansas, Gregory G. Humphreys, Thomas A. Nelson

Journal of the Arkansas Academy of Science

We radio-tracked 27 white-tailed deer (Odocoileus virginianus) weekly for one year on Fort Chaffee, Arkansas, to investigate their seasonal home ranges and movements between hunted areas and refuges on this military base. This work resulted in2,123 separate radiolocations, of which 85% (1,799) were suitable for use in home range analyses. We used the McPAAL computer package to estimate home range using the Harmonic Mean and minimum convex polygon (MCP) methods. Harmonic mean estimates were based on 95% contour lines. Home range size differed between the sexes and methods. Male home ranges were larger than those of females (t= 3.32, P<0.01; harmonic mean) (t=2.07, P<0.05; MCP). Average home range sizes for males and females based on the harmonic mean method were estimated to be 483 ha and 181 ha, respectively, whereas home range estimates for males and females using the MCP method were 636 ha and 289 ha, respectively. The average home range size for all deer was 259 ha (harmonic mean) and 379 ha (MCP). We found no evidence that females restricted their home ranges during the fawning period. However, females' home ranges expanded during the breeding season, perhaps to find mates. Few deer moved to refuge areas that were off-limits to hunters during the hunting season.


Winter Breeding As A Common Occurrence In The Ringed Salamander, Ambystoma Annulatum (Caudata: Ambystomatidae), In The Ozark National Forest Of Northcentral Arkansas, Stanley E. Trauth Jan 2000

Winter Breeding As A Common Occurrence In The Ringed Salamander, Ambystoma Annulatum (Caudata: Ambystomatidae), In The Ozark National Forest Of Northcentral Arkansas, Stanley E. Trauth

Journal of the Arkansas Academy of Science

No abstract provided.


Occurrence Of A Second Subspecies Of Box Turtle (Terrapene Carolina), In Arkansas, C. Renn Tumlison, Anthony Rocconi Jan 2000

Occurrence Of A Second Subspecies Of Box Turtle (Terrapene Carolina), In Arkansas, C. Renn Tumlison, Anthony Rocconi

Journal of the Arkansas Academy of Science

No abstract provided.


Absence Of Insect Juvenile Hormones In The American Dog Tick, Dermacentor Veriabilis (Say) (Acari: Ixodidae), And In Ornithodoros Parkeri Cooley (Acari: Argasidae), P. A. Neese, Daniel E. Sonenshine, V. L. Kallapur, C. S. Apperson, R. M. Roe Jan 2000

Absence Of Insect Juvenile Hormones In The American Dog Tick, Dermacentor Veriabilis (Say) (Acari: Ixodidae), And In Ornithodoros Parkeri Cooley (Acari: Argasidae), P. A. Neese, Daniel E. Sonenshine, V. L. Kallapur, C. S. Apperson, R. M. Roe

Biological Sciences Faculty Publications

Synganglia, salivary gland, midgut, ovary, fat body and muscle alone and in combination from the ixodid tick, Dermacentor variabilis (Say), or the argasid tick, Ornithodoros parkeri Cooley, were incubated in vitro in separate experiments with L-[methyl-3H]methionine and farnesoic acid or with [1-14C]acetate. Life stages examined in D. variabilis were 3 and 72 h old (after ecdysis) unfed nymphs, partially fed nymphs (18 and 72 h after attachment to the host), fully engorged nymphs (2 d after detachment from host), 3 and 72 h old (after eclosion) unfed females, partially fed unmated females (12–168 …


Raised Beds Prevent Waterlogging And Increase Productivity, Greg Hamilton, Derk Bakker, David Houlebrook, Cliff Spann Jan 2000

Raised Beds Prevent Waterlogging And Increase Productivity, Greg Hamilton, Derk Bakker, David Houlebrook, Cliff Spann

Journal of the Department of Agriculture, Western Australia, Series 4

Permanent Raised Beds are proving to be a revolutionary means of preventing waterlogging and a substantially increasing the productivity of wet and poorly productive land in Western Australia. In just three years, a research project has seen significant improvements in yield and reductions in waterlogging.


New Sheep Meat Breeds For Western Australia, Matthew Young Jan 2000

New Sheep Meat Breeds For Western Australia, Matthew Young

Journal of the Department of Agriculture, Western Australia, Series 4

The continuing decline in wool prices and the arrival of several new meat sheep breeds from South Africa are being seen as an opportunity for pastoral wool growers to diversify into sheep meat production, or to add value to their Merino flocks. Since the arrival of the Damara, Dorper and South African Meat Merino, the interest in these breeds has spread not only across the sheep areas of Western Australia, but also to many parts of Australia. Matthew Young reports on a number of demonstrations undertaken in recent years to assess the performance of these new breeds both on the …


Ofda2000 Brings Major Changes For Wool Industry, Andrew Peterson Jan 2000

Ofda2000 Brings Major Changes For Wool Industry, Andrew Peterson

Journal of the Department of Agriculture, Western Australia, Series 4

The classing of any wool clip into lines of uniform quality is a crucial step in optimising the value of the wool. Objective Clip Preparation (OCP) standards and training of wool classers lave led to the Australian wool clip being internationally recognised as the best classed and prepared wool in the world. However, adherence to OCP standards of clip preparation still leads to a substantial range in diameter and crimp frequency of fleeces within the main lines. Therefore, an opportunity has existed to develop improved technology to reduce the variation in quality within any main line, create lines of even …


Western Australia - A Johne's Disease Free Zone, Peter Morcombe Jan 2000

Western Australia - A Johne's Disease Free Zone, Peter Morcombe

Journal of the Department of Agriculture, Western Australia, Series 4

The control of Johne's disease (JD) in Australia is coordinated nationally by Animal Health Australia in conjunction with the livestock industries and the Commonwealth and State "Governments. Zones were established for Australia in July 1999 to control the spread of JD. These zones ensured that surveillance established the prevalence of JD, and that movement restrictions on livestock appropriate to the zone status were implemented. Following many years of surveillance and restrictions on the introduction of livestock, Western Australia has now been declared a Johne's Disease Free Zone - the first in Australia. Johne's Disease State Coordinator Peter Morcombe looks at …


Map-Making Of Plant Biomass And Leaf Area Index For Management Of Protected Areas, Loretta Gratani, Maria Fiore Crescente Jan 2000

Map-Making Of Plant Biomass And Leaf Area Index For Management Of Protected Areas, Loretta Gratani, Maria Fiore Crescente

Aliso: A Journal of Systematic and Floristic Botany

An inventory of the vegetation types of Castelporziano Estate (Rome), including examples of Mediterranean ecosystems in excellent preserved condition, was compiled. Because Leaf Area Index (LAI) changed with forest structure and developmental stages, maximum LAI provided a good estimate of maximum biomass accumulation. Plant biomass estimation, ranging from 61 tons ha-1 to 360 tons ha-1, fitted well into 14 biomass classes; the highest values (from 301 tons ha-1 to 360 tons ha-1) were related to stratified forested vegetation types, including the more mature Pinus pinea plantations, Quercus ilex evergreen forests and broad leaf mixed …


Normalizing Novelty: Regulating Biotechnological Risk At The U.S. Epa, Les Levidow, Susan Carr Jan 2000

Normalizing Novelty: Regulating Biotechnological Risk At The U.S. Epa, Les Levidow, Susan Carr

RISK: Health, Safety & Environment (1990-2002)

Drs. Levidow and Carr examine EPA's regulation of biotechnology in the field of genetically modified organisms.


'Texas Maroon’ Bluebonnet, Wayne A. Mackay, Jerry M. Parsons, Greg Grant, Steve George, Tim D. Davis, Larry Stein Jan 2000

'Texas Maroon’ Bluebonnet, Wayne A. Mackay, Jerry M. Parsons, Greg Grant, Steve George, Tim D. Davis, Larry Stein

SFA Gardens Publications

The Texas state flower, the bluebonnet, encompasses all six of the Lupinus species native to Texas. The most widespread and popular bluebonnet, Lupinus texensis Hook., is a winter annual that produces violet-blue [violet-blue group 96A, Royal Horticultural

Society (RHS), 1982] racemes in early to midspring and is predominately self-pollinating.

The Texas Dept. of Transportation uses this species widely for floral displays along roadsides throughout much of the state (Andrews, 1986). Rare white and even rarer pink variants exist in native populations, and a breeding project was initiated in 1985 to develop bluebonnets with novel flower colors for use as bedding …