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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 ...


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 ...


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.


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 ...


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.


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.


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 ...


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 ...


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 ...


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.


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 ...


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 ...


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

Verbena Neomexicana (A. Gray) Small, William Mcclain

Specimens by Name

No abstract provided.


Verbena Brasiliensis Vell., William Mcclain Dec 1991

Verbena Brasiliensis Vell., 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.


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.


Survey Of Adult Corn Rootworm Populations In Rotated Cornfields And Relationship To Larval Damage To The Subsequent Corn Crop, Jon Tollefson, David Baker, Jim Rouse, James Oleson Dec 1991

Survey Of Adult Corn Rootworm Populations In Rotated Cornfields And Relationship To Larval Damage To The Subsequent Corn Crop, Jon Tollefson, David Baker, Jim Rouse, James Oleson

Proceedings of the Integrated Crop Management Conference

Research by Chiang (1965) and Krysan et al. (1984) has demonstrated that eggs of the northern corn rootworm, Djabrotica barberi, are capable of remaining in diapause for longer than a single winter chill period. Subsequently, researchers in several northern Corn Belt states have used controlled environmental and field experiments to confirm the presence of what has come to be known as "extended diapause." In 1986 Krysan et al. used empirical evidence provided fortuitously by the Payment-In-Kind program to attribute larval damage in rotated field corn to northern corn rootworms with the extended diapause trait. During 1987 the incidence in Iowa ...


Weed Seed Dormancy And Germination, Micheal D. K. Owen Dec 1991

Weed Seed Dormancy And Germination, Micheal D. K. Owen

Proceedings of the Integrated Crop Management Conference

Weeds are consistent problems in agriculture because of seed dormancy. Without dormancy, weed seeds would not survive in the soil for any period of time. Also critical are the factors that influence dormancy. These factors which describe seed dormancy also serve to "determine" when the seed has the greatest potential to germinate successfully, and thus survive to replace the seed bank. Understanding the concepts of seed dormancy and factors that influence the continuation or termination of dormancy thus allowing germination are critical for the development of an effective weed-management program.


Soybean Residual Effects On A Following Corn Crop, Richard M. Shibles, Irvin C. Anderson, Edgar S. Escuro Dec 1991

Soybean Residual Effects On A Following Corn Crop, Richard M. Shibles, Irvin C. Anderson, Edgar S. Escuro

Proceedings of the Integrated Crop Management Conference

The reason for the yield advantage of rotations is still speculative. Differences in soil nutrients, soil moisture, diseases, insects, weeds, and soil physical properties have all been considered to be responsible for this effect. It was not until the late '70s that a non-nitrogen soybean effect on the following corn crop was substantially documented. Corn after soybeans consistently performed better than second-year corn irrespective of nitrogen fertilization. In previous work done with the soybean-corn rotation, there has never been an evaluation of the potentially different effects of soybean varieties on following corn yields. This study aimed to evaluate whether such ...


Soil Compaction Research Summary, Stewart W. Melvin, Donald C. Erbach Dec 1991

Soil Compaction Research Summary, Stewart W. Melvin, Donald C. Erbach

Proceedings of the Integrated Crop Management Conference

Soil compaction has become a major topic of discussion among scientists and crop producers in recent years. Even though some producers consider soil compaction to be a problem on their own farms, they feel resigned to the fact that there is little they can do to control it. Some recent solutions have been offered based on research efforts with soil compaction. There is significant interest in developing crop production systems with controlled traffic to help control the problem of soil compaction. There have also been new machine developments to address the problem of soil compaction, particularly with rubber tracked equipment ...


Aglime For Corn And Soybean Production, Regis Voss Dec 1991

Aglime For Corn And Soybean Production, Regis Voss

Proceedings of the Integrated Crop Management Conference

Liming acid agricultural soils has been a long-time proven practice to maintain/improve crop yields, particularly forage legumes, and to favorably affect soil chemical, biological and physical properties.


A Perspective On The 1991 Iowa Crop, Garren O. Benson Dec 1991

A Perspective On The 1991 Iowa Crop, Garren O. Benson

Proceedings of the Integrated Crop Management Conference

One of the definitions of perspective is "to see clearly". I don't claim such ability, especially in late October when neither the final crop yields nor research results are known. Most would call 1991 an unusual crop year, but I'm reminded of a former colleague who was fond of saying that in the last 30 years he had yet to see a "normal" year. Perhaps the best word to describe the 1991 crop year would be crazy. This is especially true when you consider that the state's corn and soybean yields will end up close to "average".


Soybean Cyst Nematode- Biology And Management, Gregory L. Tylka Dec 1991

Soybean Cyst Nematode- Biology And Management, Gregory L. Tylka

Proceedings of the Integrated Crop Management Conference

The soybean cyst nematode, Heterodera glycines, is a small, unsegmented plant-parasitic roundworm that attacks the roots of soybeans. Although many plant-parasitic nematodes are believed to be endemic or native to the United States, the soybean cyst nematode was apparently introduced from Japan. Soybean cyst nematode was first discovered in the United States in 1954 in North Carolina. It has since spread to 28 additional states in the Southeast and Midwest. It was first discovered in Iowa in Winnebago County in 1978. The presence of soybean cyst nematode has been confirmed in 52 counties within Iowa (Figure 1) and it is ...


Variable Rate Fertilization- Can The Technology Pay For Itself?, Michael Schmitt, Dean Fairchild Dec 1991

Variable Rate Fertilization- Can The Technology Pay For Itself?, Michael Schmitt, Dean Fairchild

Proceedings of the Integrated Crop Management Conference

Soils form a continuum across every farmer's field, constantly changing in both physical and chemical characteristics. Sometimes these changes are visible; sometimes they are completely masked to the eye. Variables such as organic matter, water-holding capacity, pH, and soil nutrient levels differ; combined, they affect crop yields. In either case, these differences should result in different management practices, including fertilizer applications, being recommended for different soils within a field.