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Full-Text Articles in Life Sciences

Who Wants To Be Healthy?, Joyce V. Fetro, David W. Hey Dec 2000

Who Wants To Be Healthy?, Joyce V. Fetro, David W. Hey

Kinesiology

No abstract provided.


Metabolic Heat: A New Way Of Looking At How Controlled Atmospheres Kill Insects, A. Carpenter, C. Downes, L. Hansen, Mark D. Shelton, R. Lill Oct 2000

Metabolic Heat: A New Way Of Looking At How Controlled Atmospheres Kill Insects, A. Carpenter, C. Downes, L. Hansen, Mark D. Shelton, R. Lill

Office of the Dean (CAFES) Scholarship

The use of calorimetry as a tool to understand the effects of controlled atmospheres (CA) on insects is briefly reviewed. A variety of data are presented to illustrate the various types of information that calorimetry can make available to researchers. The use of a calorimeter connected to a mass spectrometer to determine the occurrence of anaerobic respiration is described and reported. We conclude that calorimetry is a useful tool to simplify the experimental options when developing new insecticidal CA treatments. It can also be used for development of other treatments such as fumigants.


An Unusual Pulse In Recruitment Of Two Reef Fishes In The Galápagos Islands Coincident With The 1997–1998 El Niño, Benjamin I. Ruttenberg Sep 2000

An Unusual Pulse In Recruitment Of Two Reef Fishes In The Galápagos Islands Coincident With The 1997–1998 El Niño, Benjamin I. Ruttenberg

Biological Sciences

No abstract provided.


Palatability Of Beef Steaks Marinated With Solutions Of Calcium Chloride, Phosphate, And (Or) Beef-Flavoring, J. A. Scanga, R. J. Delmore Jr., R. P. Ames, K. E. Belk, J. D. Tatum, G. C. Smith Aug 2000

Palatability Of Beef Steaks Marinated With Solutions Of Calcium Chloride, Phosphate, And (Or) Beef-Flavoring, J. A. Scanga, R. J. Delmore Jr., R. P. Ames, K. E. Belk, J. D. Tatum, G. C. Smith

Animal Science

This study evaluated the efficacy of marination for increasing consumer acceptability of beef. Top-sirloin steaks from 28 USDA select steers were randomly assigned to one of six marination treatments: control (CT), 150 mM calcium chloride (CA), 10% solution of beef-flavoring/seasoning mixture (FL), CA and FL (CF), 2.5% sodium phosphate and FL (PF), and tap water (TW). Steaks were marinated in vacuum pouches, aged for 7 days, cooked to 70°C and evaluated by a trained sensory panel. Marination with CA did not affect tenderness ratings, but increased (P


Sequence Analysis Of Bacterial Dna In The Colon And Stomach Of The Tyrolean Iceman, Raul J. Cano, Friedrich Tiefenbrunner, Massimo Ubaldi, Clarissa Del Cueto, Stefania Luciani, Tobe Cox, Paula Orkand, Karl H. Kunzel, Franco Rollo Jul 2000

Sequence Analysis Of Bacterial Dna In The Colon And Stomach Of The Tyrolean Iceman, Raul J. Cano, Friedrich Tiefenbrunner, Massimo Ubaldi, Clarissa Del Cueto, Stefania Luciani, Tobe Cox, Paula Orkand, Karl H. Kunzel, Franco Rollo

Biological Sciences

The male human body found in an Alpine glacier on September 19, 1991 ("Tyrolean Iceman") has, for the first time in history, given scientists a chance to perform detailed anatomical, histological, and molecular investigations on the organs of a person from the Neolithic Age (5350-5100 B.P.). In the present study, tissue samples aseptically taken from the stomach and the colon of the mummy were utilized for DNA extraction, and the DNA was PCR-amplified, using primer pairs designed to bind to fragments of the 16s ribosomal RNA gene (16s rDNA) of a broad range of bacteria. The PCR products were ...


Molecular Aspect Of Leaf Senescence, Edward Himelblau, Betania Quirino, Yoo-Sun Noh, Richard Amasino Jul 2000

Molecular Aspect Of Leaf Senescence, Edward Himelblau, Betania Quirino, Yoo-Sun Noh, Richard Amasino

Biological Sciences

Senescence is the last stage of leaf development and one type of programmed cell death that occurs in plants. The relationships among senescence programs that are induced by a variety of factors have been addressed at a molecular level in recent studies. Furthermore, an overlap between the pathogen-response and senescence programs is beginning to be characterized. The complexity of the senescence program is also evident in studies of senescence-specific gene regulation and the role of photosynthesis and plant hormones in senescence regulation. New molecular-genetic approaches are expected to be useful in unraveling the molecular mechanisms of the leaf senescence program.


Serum Ferritin Concentration And Recurrence Of Colorectal Adenoma, Marilyn Tseng, E. Robert Greenberg, Robert S. Sandler, John A. Baron, Robert W. Haile, Baruch S. Blumberg, Katherine A. Mcglynn Jun 2000

Serum Ferritin Concentration And Recurrence Of Colorectal Adenoma, Marilyn Tseng, E. Robert Greenberg, Robert S. Sandler, John A. Baron, Robert W. Haile, Baruch S. Blumberg, Katherine A. Mcglynn

Kinesiology

Abstract Both body iron stores and dietary iron intake have been reported to increase risk of colorectal neoplasms. We assessed whether serum ferritin concentration was associated with recurrence of colorectal adenomas among 733 individuals with baseline determinations of ferritin as part of a multicenter clinical trial of antioxidant supplements for adenoma prevention. All study participants had at least one adenoma removed within 3 months before enrollment, and 269 of them developed one or more adenomas between follow-up colonoscopies conducted 1 and 4 years after enrollment. Baseline serum ferritin concentrations were analyzed both as a log-transformed continuous variable and as a ...


Energetics Of Larval Swimming And Metamorphosis In Four Species Of Bugula (Bryozoa), Dean E. Wendt Jun 2000

Energetics Of Larval Swimming And Metamorphosis In Four Species Of Bugula (Bryozoa), Dean E. Wendt

Biological Sciences

The amount of energy available to larvae during swimming, location of a suitable recruitment site, and metamorphosis influences the length of time they can spend in the plankton. Energetic parameters such as swimming speed, oxygen consumption during swimming and metamorphosis, and elemental carbon and nitrogen content were measured for larvae of four species of bryozoans, Bugula neritina, B. simplex, B. stolonifera, and B. turrita. The larvae of these species are aplanktotrophic with a short free-swimming phase ranging from less than one hour to a maximum of about 36 hours. There is about a fivefold difference in larval volume among the ...


Delivering Copper Within Plant Cells, Edward Himelblau, Richard M. Amasino Jun 2000

Delivering Copper Within Plant Cells, Edward Himelblau, Richard M. Amasino

Biological Sciences

Two genes recently identified in Arabidopsis thaliana may be involved in sequestering free copper ions in the cytoplasm and delivering copper to post-Golgi vesicles. The genes COPPER CHAPERONE and RESPONSIVE TO ANTAGONIST1 are homologous to copper-trafficking genes from yeast and humans. This plant copper-delivery pathway is required to create functional ethylene receptors. The pathway may also facilitate the transport of copper from senescing leaf tissue. In addition, several other genes have been identified recently that may have a role in copper salvage during senescence.


Protozoan Free Colonies Of Lepidoptera, Kingston L. H. Leong May 2000

Protozoan Free Colonies Of Lepidoptera, Kingston L. H. Leong

Biological Sciences

A method for the establishment and maintenance of colonies of Lepidoptera which are free of contamination with protozoa is provided. The colonies consists of individuals capable of breeding and producing viable, noncontaminated butterflies.


Isolating Pcr-Quality Dna From Human Feces With A Soil Dna Kit, Brian G. Clement, Christopher L. Kitts Apr 2000

Isolating Pcr-Quality Dna From Human Feces With A Soil Dna Kit, Brian G. Clement, Christopher L. Kitts

Biological Sciences

No abstract provided.


Optical Discrimination Of A Phytoplankton Species In Natural Mixed Populations, David F. Millie, Mark A. Moline, Oscar Schofield Mar 2000

Optical Discrimination Of A Phytoplankton Species In Natural Mixed Populations, David F. Millie, Mark A. Moline, Oscar Schofield

Biological Sciences

Developing optical detection techniques for discriminating particular phytoplankon species in mixed assemblages has long been a goal of aquatic scientists. Previously, a processing algorithm for phytoplankton absorption spectra was reported that suggested detection of the red tide dinoflagellate Gymnodinium breve was possible. The algorithm evaluated the fourth derivative of the particulate absorption spectrum of an unknown sample and compared it to a standard fourth derivative spectrum for G. breve using a similarity index. We report here the first-time application of this technique to the detection of G. breve in natural, mixed phytoplankton communities. Pigment and spectral absorption data were collected ...


Type I Nitroreductases In Soil Enterobacteria Reduce Tnt (2,4,6-Trinitrotoluene) And Rdx (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine), Christopher Kitts, Chad E. Green, Rebecca A. Otley, Marc A. Alvarez, Pat J. Unkefer Mar 2000

Type I Nitroreductases In Soil Enterobacteria Reduce Tnt (2,4,6-Trinitrotoluene) And Rdx (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine), Christopher Kitts, Chad E. Green, Rebecca A. Otley, Marc A. Alvarez, Pat J. Unkefer

Biological Sciences

Many enteric bacteria express a type I oxygen-insensitive nitroreductase, which reduces nitro groups on many different nitroaromatic compounds under aerobic conditions. Enzymatic reduction of nitramines was also documented in enteric bacteria under anaerobic conditions. This study indicates that nitramine reduction in enteric bacteria is carried out by the type I, or oxygen-insensitive nitroreductase, rather than a type II enzyme. The enteric bacterium Morganella morganii strain B2 with documented hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) nitroreductase activity, and Enterobacter cloacae strain 96-3 with documented 2,4,6-trinitrotoluene (TNT) nitroreductase activity, were used here to show that the explosives TNT and RDX ...


Estimation Of Base Temperatures For Nine Weed Species, Scott J. Steinmaus, Timothy S. Prather, Jodie S. Holt Feb 2000

Estimation Of Base Temperatures For Nine Weed Species, Scott J. Steinmaus, Timothy S. Prather, Jodie S. Holt

Biological Sciences

Experiments were conducted to test several methods for estimating low temperature thresholds for seed germination. Temperature responses of nine weeds common in annual agroecosystems were assessed in temperature gradient experiments. Species included summer annuals (Amaranthus albus, A. palmeri, Digitaria sanguinalis, Echinochloa crus-galli, Portulaca oleracea, and Setaria glauca), winter annuals (Hirschfeldia incana and Sonchus oleraceus), and Conyza canadensis, which is classified as a summer or winter annual. The temperature below which development ceases (Tbase) was estimated as the x-intercept of four conventional germination rate indices regressed on temperature, by repeated probit analysis, and by a mathematical approach. An overall ...


Fork-Tailed Katydid Studies, David H. Headrick Jan 2000

Fork-Tailed Katydid Studies, David H. Headrick

Horticulture and Crop Science

The fork-tailed katydid, Scudderia furcata Brunner (Orthoptera: Tettigoniidae) was considered a minor pest of citrus in California, but in the last few years has increasingly become a problem due to reduction in organophosphate and carbamate pesticides (Grafton-Cardwell 1999). Our objective is to study the biology and behavior of the fork-tailed katydid as a pest of commercially grown citrus in order to develop ecologically-based control methods for application in commercial citrus production.


Micronesia: Steps In The Right Direction, Aydin Nazmi Jan 2000

Micronesia: Steps In The Right Direction, Aydin Nazmi

Food Science and Nutrition

As I watch the hazy orange sun sink into the still blue sea overlooking Chuuk lagoon, I marked the end of another seemingly ordinary day in the Federated States of Micronesia. But this October day was special—it marked the beginning of a promising new era in Chuuk’s fight against HIV and AIDS. For the past few months, several proceedings had set into motion a cascade of events that would ultimately (hopefully) benefit and educate the people of Chuuk state.


Evaluation Of Commercial Adjuncts For Use In Cheese Ripening: 5. Effect Of Added Freeze-Shocked Adjunct Lactobacilli On Proteolysis And Sensory Quality Of Reduced Fat Cheddar Cheese, S. A. Madkor, P. S. Tong, M. El Soda Jan 2000

Evaluation Of Commercial Adjuncts For Use In Cheese Ripening: 5. Effect Of Added Freeze-Shocked Adjunct Lactobacilli On Proteolysis And Sensory Quality Of Reduced Fat Cheddar Cheese, S. A. Madkor, P. S. Tong, M. El Soda

Dairy Science

No abstract provided.


Evaluation Of Commercial Adjuncts For Use In Cheese Ripening : 4. Comparison Between Attenuated And Not Attenuated Lactobacilli, M. El-Soda, S. A. Madkor, P. S. Tong Jan 2000

Evaluation Of Commercial Adjuncts For Use In Cheese Ripening : 4. Comparison Between Attenuated And Not Attenuated Lactobacilli, M. El-Soda, S. A. Madkor, P. S. Tong

Dairy Science

No abstract provided.


Eating Frequency And Risk Of Colorectal Cancer, Marilyn Tseng, Deborah D. Ingram, Rebecca Darden, Regina G. Ziegler, Matthew P. Longnecker Jan 2000

Eating Frequency And Risk Of Colorectal Cancer, Marilyn Tseng, Deborah D. Ingram, Rebecca Darden, Regina G. Ziegler, Matthew P. Longnecker

Kinesiology

Case-control studies have found elevated risk of colorectal cancer with higher eating frequency. The present analyses, the first to examine this association using prospectively collected information, utilized nationally representative data from the Epidemiologic Follow-Up Study of the First National Health and Nutrition Examination Survey (NHEFS). The study population included 9,978 subjects followed from 1982–84 to 1992. Colorectal cancer cases (n = 141) were identified by self-report, hospital records, and death certificates. Interviews conducted in 1982–84 provided information on meal and snack frequencies and covariates of interest. Relative risk (RR) of colorectal cancer and 95% confidence intervals (CI) were ...


Socialization Of Prospective Physical Education Teachers: The Story Of New Blood, Camille P. O'Bryant, Mary O'Sullivan, Jeanne Raudensky Jan 2000

Socialization Of Prospective Physical Education Teachers: The Story Of New Blood, Camille P. O'Bryant, Mary O'Sullivan, Jeanne Raudensky

Kinesiology

There has been much criticism of how teachers are prepared to teach and physical education has not been immune from this criticism. Despite numerous efforts to improve the content and focus of teacher education programmes there is still a paucity of programme evaluation research on the efficacy of these teacher education programmes (Metzler & Tjeerdsma, 1998). This paper reports on part of a yearlong investigation on the efficacy of a graduate physical education teacher education programme to prepare teachers. The focus of this aspect of the study was to identify what attracted graduate students to pursue a teaching career and what ...


Country Of Birth And Prevalence Of Gallbladder Disease In Mexican Americans, Marilyn Tseng, Robert Millikan, Kurt R. Maurer, Meena Khare, James E. Everhart, Robert S. Sandler Jan 2000

Country Of Birth And Prevalence Of Gallbladder Disease In Mexican Americans, Marilyn Tseng, Robert Millikan, Kurt R. Maurer, Meena Khare, James E. Everhart, Robert S. Sandler

Kinesiology

OBJECTIVES: This research sought to describe the association between country of birth and gallbladder disease (GBD) in Mexican Americans, identify subgroups at especially high risk, and identify risk factors that may mediate a birthplace-GBD association. DESIGN: Cross-sectional. METHODS: Our study population included 4157 Mexican Americans aged 20-74 who participated in the 1988-94 third National Health and Nutrition Examination Survey. GBD was diagnosed by ultrasound. Information on country of birth, education, income, and selected GBD risk factors was obtained from interviews. Prevalence odds ratios (POR) for GBD in Mexico- vs. US-born Mexican Americans were estimated by unconditional logistic regression, along with ...


Energetic Dynamics And Anuran Breeding Phenology: Insights From A Dynamic Game, Shannon J. Mccauley, Sarah S. Bouchard, Brian J. Farina, Kavita Isvaran, Suhel Quader, Daniel W. Wood, Colette M. St. Mary Jan 2000

Energetic Dynamics And Anuran Breeding Phenology: Insights From A Dynamic Game, Shannon J. Mccauley, Sarah S. Bouchard, Brian J. Farina, Kavita Isvaran, Suhel Quader, Daniel W. Wood, Colette M. St. Mary

Biological Sciences

We designed a dynamic optimization model to examine anuran-breeding phenologies. We evaluated the fitness consequences for males adopting one of four alternative strategies: calling, satelliting, foraging, or hiding. Various factors potentially influence male behavior, including energy reserves, predation risk, cost of calling, probability of finding food, distribution of male energy states in the population, and probability of surviving to another breeding season. We manipulated these parameters to determine how strongly each affects breeding phenology and chorus structure. Manipulating parameters related to the energetic costs and benefits of individual decisions, we generated the three basic patterns of anuran breeding phenology: explosive ...


Time Course And Magnitude Of Synthesis Of Heat-Shock Proteins In Congeneric Marine Snails (Genus Tegula) From Different Tidal Heights, Lars Tomanek, George N. Somero Jan 2000

Time Course And Magnitude Of Synthesis Of Heat-Shock Proteins In Congeneric Marine Snails (Genus Tegula) From Different Tidal Heights, Lars Tomanek, George N. Somero

Biological Sciences

The time course and magnitude of the heat-shock response in relation to severity of thermal stress are important, yet poorly understood, aspects of thermotolerance. We examined patterns of protein synthesis in congeneric marine snails (genus Tegula) that occur at different heights along the subtidal to intertidal gradient after a thermal exposure (30°C for 2.5 h, followed by 50 h recovery at 13°C) that induced the heat-shock response. We monitored the kinetics and magnitudes of protein synthesis by quantifying incorporation of 35S-labeled methionine and cysteine into newly synthesized proteins and observed synthesis of putative heat-shock proteins (hsp ...


Optical Fractionation Of Chlorophyll And Primary Production For Coastal Waters Of The Southern Ocean, Mark A. Moline, Barbara B. Prezelin Jan 2000

Optical Fractionation Of Chlorophyll And Primary Production For Coastal Waters Of The Southern Ocean, Mark A. Moline, Barbara B. Prezelin

Biological Sciences

Our objective was to quantify the potential variability in remotely sensed chlorophyll a (Chl a) and primary productivity in coastal waters of the Southern Ocean. From data collected throughout the springs/summers of 1991–1994, we calculated the proportion of water column Chl a and primary productivity within the upper optical attenuation length (K −1 par) and the satellite-weighted depth. The temporal variability was resolved every 2–3 days and was observed to be greater within years than between years. Three-year averages (n=223) revealed that 10.2 ± 3.6% of total Chl a and 14.8 ± 6.5% of ...


Temporal And Spatial Variations In Macrofouling Of Silicone Fouling-Release Coatings, Christina Darkangelo Wood, Kathryn Truby, Judith Stein, Deborah Wiebe, Eric Holm, Dean Wendt, Celia Smith, Christopher Kavanagh, Jean Montemarano, Geoff Swain, Anne Meyer Jan 2000

Temporal And Spatial Variations In Macrofouling Of Silicone Fouling-Release Coatings, Christina Darkangelo Wood, Kathryn Truby, Judith Stein, Deborah Wiebe, Eric Holm, Dean Wendt, Celia Smith, Christopher Kavanagh, Jean Montemarano, Geoff Swain, Anne Meyer

Biological Sciences

Nontoxic, low surface free energy silicone coatings having reduced biofouling adhesion strength have been developed as an alternative to antifouling paints. Silicone coatings permit macrofouling to adhere; however, fouling can be removed easily by water pressure or light scrubbing. One of the current methods used to evaluate the performance of non-toxic silicone fouling-release coatings relies heavily on fouling coverage. The organismal community structure as well as total coverage can affect the ease of fouling removal from these coatings. This paper explores fouling coverage and organismal adhesion over time. Long-term fouling coverage data were collected at four sites (in Massachusetts, Hawaii ...


Evaluation Of The Performance Enhancement Of Silicone Biofouling-Release Coatings By Oil Incorporation, Kathryn Truby, Christina Wood, Judith Stein, James Cella, John Carpenter, Christopher Kavanagh, Geoff Swain, Deborah Wiebe, David Lapota, Anne Meyer, Eric Holm, Dean Wendt, Celia Smith, Jean Montemarano Jan 2000

Evaluation Of The Performance Enhancement Of Silicone Biofouling-Release Coatings By Oil Incorporation, Kathryn Truby, Christina Wood, Judith Stein, James Cella, John Carpenter, Christopher Kavanagh, Geoff Swain, Deborah Wiebe, David Lapota, Anne Meyer, Eric Holm, Dean Wendt, Celia Smith, Jean Montemarano

Biological Sciences

In response to increased evidence of ecosystem damage by toxic antifouling paints, many researchers have developed nontoxic silicone fouling release coatings. The fouling release capability of these Systems may be improved by adding nonbonding silicone oils to the coating matrix. This idea has been tested by comparing the adhesion strength of hard- and soft-fouling organisms on a cured polydimethylsilicone (PDMS) network to that of the same network containing free polydi-methyldiphenylsilicone (PDMDPS) oil at five exposure sites in North America and Hawaii. Fouling coverage is discussed, together with the bioadhesion data, to emphasize that although these coatings foul the fouling is ...