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1991

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Full-Text Articles in Life Sciences

Ua66/6/3/1 Biennial Report, Kentucky Gamma, Alpha Epsilon Delta Dec 1991

Ua66/6/3/1 Biennial Report, Kentucky Gamma, Alpha Epsilon Delta

Student Organizations

Biennial report created by and about the Kentucky Gamma Chapter of Alpha Epsilon Delta premedical honor society sponsored by WKU Biology.


Port Everglades Macroinvertebrate Monitoring: Monitoring Of Benthic Macroinvertebrate Assemblages At The Southport Turning Basin And Adjacent Areas Of John U. Lloyd State Recreation Area: August 1991, Charles G. Messing, Richard E. Dodge, Alan Sosnow Dec 1991

Port Everglades Macroinvertebrate Monitoring: Monitoring Of Benthic Macroinvertebrate Assemblages At The Southport Turning Basin And Adjacent Areas Of John U. Lloyd State Recreation Area: August 1991, Charles G. Messing, Richard E. Dodge, Alan Sosnow

Marine & Environmental Sciences Faculty Reports

This report documents the August 1991 monitoring of benthic macroinvertebrate assemblages in the Port Everglades Southport turning basin vicinity and adjacent areas of John U. Lloyd State Recreation Area. This is the first monitoring effort of the series carried out by Nova University Oceanographic Center. As of this sampling period, the turning basin is complete and in operation; mitigation areas in John U. Lloyd Park exhibit considerable vegetative expansion of cord grass, growth of mangrove seedlings, and natural recruitment of additional mangrove propagules (including black and white mangroves).

Sampling was carried out during the last week of August and extended ...


Microbeam Studies Of The Sensitivity Of Structures Within Living Cells, L. A. Braby Dec 1991

Microbeam Studies Of The Sensitivity Of Structures Within Living Cells, L. A. Braby

Scanning Microscopy

Determining the biological effects of low doses of radiation with high linear energy transfer (LET) is complicated by the stochastic nature of charged-particle interactions. Populations of cells exposed to very low radiation doses contain a few cells which have been hit by a charged particle, while the majority of the cells receive no radiation damage. At somewhat higher doses, a few cells receive two or more events. Because the effects of damage produced by separate events can interact in the cell, we have had to make assumptions about the nature of these interactions in order to interpret the results of ...


The Effect Of Colcemid On The Heat Survival Of Mitotic V79 Chinese Hamster Cells, J. G. Szekely, G. P. Raaphorst, A. U. Lobreau, S. Delaney, E. I. Azzam Dec 1991

The Effect Of Colcemid On The Heat Survival Of Mitotic V79 Chinese Hamster Cells, J. G. Szekely, G. P. Raaphorst, A. U. Lobreau, S. Delaney, E. I. Azzam

Scanning Microscopy

V79 Chinese hamster cells were collected by colcemid addition to study the effect of heat on mitosis. When they were heated at 42°C and 45°C in the presence of 0.06 μg/mL colcemid, cell survival increased over the control samples, which were heated in ordinary medium. Scanning electron microscopy showed that cells heated to 45°C in the presence or absence of colcemid had fewer microvilli on the surface, but they did not have increased bleb formation. Transmission electron microscopy showed that the chromatin was diffuse in the heated cells and the kinetochores were indistinct. The mitochondria ...


Retinoic Acid Glucuronide Preparations For Application To The Skin, Arun B. Barua, Desiree Gunning, James A. Olson Dec 1991

Retinoic Acid Glucuronide Preparations For Application To The Skin, Arun B. Barua, Desiree Gunning, James A. Olson

Iowa State University Patents

A method and preparation are described for treating human skin with retinoic acid glucuronide (RAG) in a topical carrier. For treatment of acne or wrinkled skin, RAG can be applied in an effective amount which is nonirritating to the skin. Retinoid dermatitis, an objectionable side effect of topical application of retinoid compounds, can thereby be avoided.


Apparatus And Method For Transient Thermal Infrared Emission Spectrometry, John F. Mcclelland, Roger W. Jones Dec 1991

Apparatus And Method For Transient Thermal Infrared Emission Spectrometry, John F. Mcclelland, Roger W. Jones

Iowa State University Patents

A method and apparatus for enabling analysis of a solid material (16, 42) by applying energy from an energy source (20, 70) top a surface region of the solid material sufficient to cause transient heating in a thin surface layer portion of the solid material (16, 42) so as to enable transient thermal emission of infrared radiation from the thin surface layer portion, and by detecting with a spectrometer/detector (28, 58) substantially only the transient thermal emission of infrared radiation from the thin surface layer portion of the solid material. The detected transient thermal emission of infrared radiation is ...


The Microvasculature Of Human Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection I. Tongue Papillae, Q. X. Yu, W. Ran, K. M. Pang, H. P. Philipsen, J. Theilade, X. H. Chen, Y. C. Mok Dec 1991

The Microvasculature Of Human Oral Mucosa Using Vascular Corrosion Casts And India Ink Injection I. Tongue Papillae, Q. X. Yu, W. Ran, K. M. Pang, H. P. Philipsen, J. Theilade, X. H. Chen, Y. C. Mok

Scanning Microscopy

The microvasculature of human tongue papillae originating from 9 males and 6 females, aged 0.5 to 2 years was studied by scanning electron microscopy (SEM) of vascular corrosion casts and by light microscopy (LM) of India ink injected specimens. All papillae showed a microvasculature characterized by primary, secondary and tertiary capillary loops. In the filiform papillae the loops were generally arranged in a corolla-like pattern with the tertiary loops demonstrating a hair-pin shape. The fungiform papillae showed basically a similar architectural pattern although the loops were somewhat more compact and complex in structure. A small, shallow depression of the ...


The State Of Interbreed Epds, Jim Gibb Dec 1991

The State Of Interbreed Epds, Jim Gibb

South Dakota Beef Seedstock Symposium, 1991

During the past ten years, the use of Expected Progeny Differences (EPDs) by both seedstock producers and commercial cattlemen has increased markedly. EPDs have proven to be very valuable for discerning within breed sire differences, but are still of no value for comparing sires between breeds. Even though EPDs were never intended for across breed comparisons, many commercial cattlemen find this limitation to be very frustrating.


Current Status Of National Cattle Evaluation Programs For Carcass Traits, Larry Benyshek Dec 1991

Current Status Of National Cattle Evaluation Programs For Carcass Traits, Larry Benyshek

South Dakota Beef Seedstock Symposium, 1991

At present, diet conscious consumers are exerting considerable pressure on the beef industry. Consumers continually indicate they are concerned about, and in fact, will not tolerate fat associated with red meat products (Breidenstein, 1988). This has resulted in many retailers trimming various cuts of beef to 1/8 inch of subcutaneous fat and in some cases a complete trimming of fat. It is probably conservative to estimate the industry produces an excess of 500 million pounds of fat each year from those carcasses with a yield grade above two. This excess fat represents the nutritional energy in more than a ...


Which Cows Are More Efficient, D. M. Marshall Dec 1991

Which Cows Are More Efficient, D. M. Marshall

South Dakota Beef Seedstock Symposium, 1991

On the surface, the topic of cow efficiency may seem to be primarily of importance to commercial cow-calf producers. The topic is also of importance to seedstock producers, because the primary purpose of the seedstock industry is to provide genetic resources for the commercial industry. It is critical that seedstock producers develop a good understanding of the challenges faced by commercial producers in order to provide the best possible services. Feed costs for the cow herd represent the single largest expense in producing retail beef. The proportion of total energy utilized in beef production that is required to support the ...


Calving Difficulty In Beef Cattle: Part I, Harlan D. Ritchie, Peter T. Anderson Dec 1991

Calving Difficulty In Beef Cattle: Part I, Harlan D. Ritchie, Peter T. Anderson

South Dakota Beef Seedstock Symposium, 1991

Calving difficulty (dystocia) can increase calf losses, cow mortality, and veterinary and labor costs, as well as delay return to estrus, and lower conception rates. In two studies at the U.S. Meat Animal Research Center (MARC), Clay Center, Nebraska, calf losses within 24 hours of birth averaged 4 percent for those born with little or no assistance compared to 16 percent for those requiring assistance. Calf mortality increased by a 0.35 percent per pound increase in birth weight. In a Hereford herd at the U.S. Livestock and Range Research Station. Miles City, Montana, 57 percent of all ...


Real-Time Ultrasound To Predict Carcass Traits In Live Cattle, Gene Rouse Dec 1991

Real-Time Ultrasound To Predict Carcass Traits In Live Cattle, Gene Rouse

South Dakota Beef Seedstock Symposium, 1991

Ultrasound technology offers a low-cost alternative to expensive and time-consuming progeny testing of beef sires for carcass merit. Expected progeny differences (EPDs) for carcass traits such as fat cover, ribeye area, and marbling would provide a tremendous tool to the beef 'cattle industry for producing a high quality, uniform end product. With these EPDs, breeders and commercial bull buyers will be able to directionally change the end product through genetic improvement programs. The objective of this report is to relate the accuracy with which fat cover and ribeye area can be measured with ultrasound equipment when compared with carcass measurements ...


Northeast Research Station Watertown, South Dakota Annual Progress Report, 1991, Agricultural Experiment Station, Plant Science Department Dec 1991

Northeast Research Station Watertown, South Dakota Annual Progress Report, 1991, Agricultural Experiment Station, Plant Science Department

Agricultural Experiment Station and Research Farm Annual Reports

This is the 1991 annual progress report for the Northeast Research Station in Watertown, South Dakota. This report is issued by the South Dakota Agricultural Experiment Station and the South Dakota State University Plant Science Department. This report includes information on the 1991 crop season, including precipitation data, grain and crop research, breeding, and variety testing, soybean row space study, weed control studies and cost, crop performance test, 1991 crop yields system productivity from 1985-1991, plant nutrition, soil test and research, profitability comparisons for farming system trials, weed populations.


Computations Associated With National Beef Cattle Evaluation Programs, Larry Benyshek Dec 1991

Computations Associated With National Beef Cattle Evaluation Programs, Larry Benyshek

South Dakota Beef Seedstock Symposium, 1991

In 1971-72 the first U.S. National Sire Summary was published by a beef cattle breed association. At that time the idea of extending beef performance records into a national progeny testing program was indeed revolutionary. Until 1972, truly accurate comparisons of bulls could only be made within a herd-year-season contemporary group. The first and subsequent National Sire Summaries compared bulls across herds and/or generations.


Establishing Genetic Lines For Goal Oriented Buyers, Richard Janssen Dec 1991

Establishing Genetic Lines For Goal Oriented Buyers, Richard Janssen

South Dakota Beef Seedstock Symposium, 1991

No abstract provided.


Calving Difficulty In Beef Cattle: Part Ii, Harlan D. Ritchie, Peter T. Anderson Dec 1991

Calving Difficulty In Beef Cattle: Part Ii, Harlan D. Ritchie, Peter T. Anderson

South Dakota Beef Seedstock Symposium, 1991

Many cattlemen believe reducing dietary energy during late pregnancy will decrease fetal size resulting in improved calving ease, whereas increasing energy will increase fetal size leading to a higher incidence of dystocia. Generally speaking, research has shown that lowering the energy allowance will decrease birth weight but will not significantly reduce dystocia. At MARC, Hereford and Angus 2-year-old heifers were fed three levels of energy (10.8, 13.7 or 17 .0 lb TDN/head/day) for 90 days prior to calving. Increasing the level of dietary energy resulted in increased birth weight but not increased dystocia; in fact, the ...


Impacts Of Types On Feed And Market Requirements, Donald L. Boggs Dec 1991

Impacts Of Types On Feed And Market Requirements, Donald L. Boggs

South Dakota Beef Seedstock Symposium, 1991

So you want to make them bigger! Or, do you want to add some milk to your cow herd? Improvements in these and other traits offer opportunities to increase production through higher weaning weights. However, the increased outputs are accompanied by increased feed and management inputs. Available research indicates that the increased production may or may not outweigh the increased inputs. Mature cow size and level of milk production are typically the factors considered when changes in cattle type are discussed. Numerous research studies have been conducted to evaluate the effects of these factors on biological and economic efficiency. In ...


Beef Cattle National Genetic Evaluation Programs, Larry Benyshek Dec 1991

Beef Cattle National Genetic Evaluation Programs, Larry Benyshek

South Dakota Beef Seedstock Symposium, 1991

Selection alters the frequency of genes in a population (breed) affecting a particular characteristic. Population genetic change is difficult for breeders to understand because they deal with individuals when making selection decisions and in their merchandising programs. Nevertheless, breeds (populations) which practice intense selection for characteristics of economic importance to the cattle industry will change genetically and eventually be the successful populations because they will leave the most progeny in the next generation. The genetic improvement of a population (breed) cannot overlook the individual because the individual, if selected, is the vehicle containing the genes which are to be passed ...


Verbena Brasiliensis Vell., William Mcclain Dec 1991

Verbena Brasiliensis Vell., William Mcclain

Specimens by Name

No abstract provided.


Verbena Neomexicana (A. Gray) Small, William Mcclain Dec 1991

Verbena Neomexicana (A. Gray) Small, William Mcclain

Specimens by Name

No abstract provided.


Phoradendron Tomentosum Oliver, W. E. Mcclain Dec 1991

Phoradendron Tomentosum Oliver, W. E. Mcclain

Specimens by Name

No abstract provided.


1991 South Dakota Beef Seedstock Symposium, December 13-14, 1991, Department Of Animal And Range Sciences, South Dakota State University Dec 1991

1991 South Dakota Beef Seedstock Symposium, December 13-14, 1991, Department Of Animal And Range Sciences, South Dakota State University

South Dakota Beef Seedstock Symposium, 1991

This is the complete publication of presentations from the 1991 South Dakota Seedstock Symposium held on December 13-14, 1991 at South Dakota State University, Brookings.


Ua12/2/1 All Creatures Great & Small, Wku Student Affairs Dec 1991

Ua12/2/1 All Creatures Great & Small, Wku Student Affairs

WKU Archives Records

Special magazine edition of the College Heights Herald:

  • Hadley, Kim. Each Day is Something Extra – Reg Laswell, AIDS, HIV
  • Baldwin, Paul. You Have to Love Animals to Work Here – Bowling Green/Warren County Animal Shelter



New Directions In Scanning Electron Microscopy Cathodoluminescence Microcharacterization, D. B. Holt Dec 1991

New Directions In Scanning Electron Microscopy Cathodoluminescence Microcharacterization, D. B. Holt

Scanning Microscopy

The general principles of the low-temperature spectroscopic cathodoluminescence (LTSCL) technique in the scanning electron microscope (SEM) are outlined. CL microscopy and spectroscopy are now being extended in new directions. Analysis of the intrinsic CL from quantum well materials by LTSCL is proving valuable for microcharacterization and such work can be expected to expand rapidly. The main, early CL results in this exciting field are summarized here. In geology, CL microscopy, without spectroscopy, is widely used via electron-beam attachments to light microscopes and the addition of spectral analysis to these studies is overdue. Much CL from minerals and ceramics comes from ...


Tooth Tissues Of Certain Sharks And Lungfishes, Yasutomo Iwai-Liao, Yoshikage Higashi, Yoshitaka Tamada Dec 1991

Tooth Tissues Of Certain Sharks And Lungfishes, Yasutomo Iwai-Liao, Yoshikage Higashi, Yoshitaka Tamada

Scanning Microscopy

A comparative odontologic study was conducted on teeth and their supporting tissues from extant sharks, fossil sharks, and living lungfishes using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) X-ray microprobe to investigate evolutionary changes in tooth structure of the fishes.

No histological differences between the extant and fossil teeth of lamnoid sharks were observed. The weight percent of calcium in osteodentin of the fossil shark was higher than that in the extant shark. The weight percents of both P and Ca of tooth tissues in the giant extinct shark showed comparatively low values.

Both the upper and lower ...


Health Insurance For Employees, Neil E. Harl Dec 1991

Health Insurance For Employees, Neil E. Harl

Agricultural Law Digest

The rising cost of medical and hospital care and the cost of insurance coverage have led to increased interest in ways to make such costs fully deductible without the benefits being includible in income for the taxpayer. Through 1991 (and the first six months of 1992 if the President signs the bill extending the deduction through June 1992), a 25 percent deduction is allowed for health and accident amounts for self-employed individuals provided — (1) the taxpayer is not eligible to participate in any subsidized health plan maintained by an employer for the taxpayer or the taxpayer's spouse and (2 ...


Cases, Regulations, And Statutes, Robert P. Achenbach Jr. Dec 1991

Cases, Regulations, And Statutes, Robert P. Achenbach Jr.

Agricultural Law Digest

No abstract provided.


Cumulative Index: Vol 1, Nos. 13–24, Agricultural Law Digest Dec 1991

Cumulative Index: Vol 1, Nos. 13–24, Agricultural Law Digest

Agricultural Law Digest

No abstract provided.


Panchromatic And Spectral Characterization Of Cu Contaminated Semi-Insulating Gaas, Thomas E. Zirkle, Stephan Myhajlenko, Nam Soo Kang, Ronald J. Roedel, Dieter K. Schroder Dec 1991

Panchromatic And Spectral Characterization Of Cu Contaminated Semi-Insulating Gaas, Thomas E. Zirkle, Stephan Myhajlenko, Nam Soo Kang, Ronald J. Roedel, Dieter K. Schroder

Scanning Microscopy

Panchromatic (integral) and spectrally resolved cathodoluminescence characterization was used to investigate the near surface gettering properties of Cu in liquid-encapsulated, Czochralski-grown, undoped semi-insulating (SI) GaAs. Samples from two sources were investigated to determine if gettering treatments applied to GaAs result in improvements in uniformity similar to those observed in gettered Si. Before Cu contamination, typical cellular structure is observed for all samples. Experimentally, it is found that the panchromatic CL images change significantly after Cu doping and subsequent gettering processing for all samples. A contrast reversal is generally observed after Cu contamination. After gettering, the image of the samples from ...


A Quality Audit Of The Beef Industry, Gary C. Smith Dec 1991

A Quality Audit Of The Beef Industry, Gary C. Smith

Range Beef Cow Symposium

"Quality," in the context it will be discussed here, includes all of the factors that affect value/desirability of U.S. slaughter cattle (steers/heifers slaughtered at 9 to 42 months of age, immediately following a period of 90 to 300 days of high-concentrate feeding) in terms of the value/desirability of their carcasses and dress-off/offal items.