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Full-Text Articles in Life Sciences

Using Sport Science To Improve Coaching: A Case Study Of The American Record Holder In The Women’S Hammer Throw, Iain Hunter, Erin Gilreath, Larry W. Judge Dec 2008

Using Sport Science To Improve Coaching: A Case Study Of The American Record Holder In The Women’S Hammer Throw, Iain Hunter, Erin Gilreath, Larry W. Judge

Faculty Publications

Conclusions from biomechanical data can make a significant difference in the performance of athletes in the hammer throw if properly understood by coaches. By utilizing this scientific approach to the hammer throw event, the throws coach will be able to determine more accurate adjustments and devise training stimuli to better accommodate the athlete. In this case study, we have attempted to bridge the gap between the researcher and the coach in our approach to teaching the hammer throw, by integrating biomechanical analysis. We have employed the use of video analysis as an essential part of our coaching/teaching system. This USATF …


A Simple, Anatomically Based Correction To The Conventional Ankle Joint Center, Dustin A. Bruening, Ashlie N. Crewe, Frank L. Buczek Dec 2008

A Simple, Anatomically Based Correction To The Conventional Ankle Joint Center, Dustin A. Bruening, Ashlie N. Crewe, Frank L. Buczek

Faculty Publications

Background

Conventional motion analysis studies define the ankle joint center as the midpoint between the most medial and lateral aspects of the malleoli, yet research points toward a more distal joint center location. The purpose of this study was to develop and evaluate an anatomically based correction that would move the conventional ankle joint center to a more accurate location.

Methods

Lower extremity radiographs from 30 pediatric patients were analyzed retrospectively. An offset between the conventional and more accurate ankle joint centers was measured and correlated to other common anatomical measures based on conventional skin mounted marker positions. The best …


Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell Nov 2008

Timing Of Supplementation Of Selenium And Isoflavones Determines Prostate Cancer Risk Factor Reduction In Rats, Merrill J. Christensen, Jessica R. Tolman, Edwin D. Lephart, Dennis L. Eggett, Kenneth Setchell

Faculty Publications

High dietary intake of selenium or isoflavones reduces risk factors for prostate cancer. We tested whether combined supplementation of these two dietary components would reduce prostate cancer risk factors in rats more than supplementation of each component individually. Methods Male Noble rat pups were exposed from conception to diets containing an adequate (0.33-0.45 mg/kg diet) or high (3.33-3.45 mg/kg) concentration of selenium as Se-methylselenocysteine and a low (10 mg/kg) or high (600 mg/kg) level of isoflavones in a 2 x 2 factorial design. Pups consumed their respective diets until sacrifice at 35, 100, or 200 days. Male Noble rat breeders, …


Commercial Evaluation Of A Continuous Micronutrient Fortification Process For Nixtamal Tortillas, Michael L. Dunn, Sergio O. Serna-Saldivar, Diana Sanchez-Hernandez, Robert W. Griffin Nov 2008

Commercial Evaluation Of A Continuous Micronutrient Fortification Process For Nixtamal Tortillas, Michael L. Dunn, Sergio O. Serna-Saldivar, Diana Sanchez-Hernandez, Robert W. Griffin

Faculty Publications

The corn tortilla plays an integral role in the Mexican diet and is an ideal vehicle for micronutrient fortification. Approximately 60% of corn tortillas in Mexico are produced from nixtamal, with the remainder prepared from masa flour. A process for continuous fortification of nixtamal tortillas was evaluated in two commercial mills in Mexico. A commercial powder dosifier was used to add micronutrient premix containing iron, zinc, folic acid, niacin, riboflavin, and thiamin to nixtamal (1 g/kg) as it was milled. After training and preliminary sampling, mills produced fortified tortillas unassisted for four weeks. Masa flow rates over a four-day period …


Calculating Expected Dna Remnants From Ancient Founding Events In Human Population Genetics, Nathan C. Sheffield, Keith A. Crandall, Andrew Stacey Oct 2008

Calculating Expected Dna Remnants From Ancient Founding Events In Human Population Genetics, Nathan C. Sheffield, Keith A. Crandall, Andrew Stacey

Faculty Publications

Background- Recent advancements in sequencing and computational technologies have led to rapid generation and analysis of high quality genetic data. Such genetic data have achieved wide acceptance in studies of historic human population origins and admixture. However, in studies relating to small, recent admixture events, genetic factors such as historic population sizes, genetic drift, and mutation can have pronounced effects on data reliability and utility. To address these issues we conducted genetic simulations targeting influential genetic parameters in admixed populations. Results- We performed a series of simulations, adjusting variable values to assess the affect of these genetic parameters on current …


Many Species In One: Dna Barcoding Overestimates The Number Of Species When Nuclear Mitochondrial Pseudogenes Are Coamplified, Michael F. Whiting, Hojun Song, Keith A. Crandall, Jennifer E. Buhay Sep 2008

Many Species In One: Dna Barcoding Overestimates The Number Of Species When Nuclear Mitochondrial Pseudogenes Are Coamplified, Michael F. Whiting, Hojun Song, Keith A. Crandall, Jennifer E. Buhay

Faculty Publications

Nuclear mitochondrial pseudogenes (numts) are nonfunctional copies of mtDNA in the nucleus that have been found in major clades of eukaryotic organisms.


Resulting Shifts In Percentile And Standard Placements After Comparison Of The Bod Pod And Dxa, Timothy Heden, Steve Shepard, John Smith, Kay Covington, James D. Lecheminant Sep 2008

Resulting Shifts In Percentile And Standard Placements After Comparison Of The Bod Pod And Dxa, Timothy Heden, Steve Shepard, John Smith, Kay Covington, James D. Lecheminant

Faculty Publications

Int J Exerc Sci 1(3) : 113-124, 2008. The purpose of this study was to determine the validity of the BOD POD® when compared to the DXA and if placement on a percentile chart and standard table is affected by any differences between the two measures. A total of 244 (27.7 ± 10.8 yrs, 77.3 ± 16.1 kg, 171.4 ± 10.1 cm, 26.31 ± 5.42 BMI) males and females between the ages of 18 and 52 were recruited to participate in this study. The participant’s body fat percentage (%BF) was tested in random order on the BOD POD® and DXA …


Decline In A Dominant Invertebrate Species Contributes To Altered Carbon Cycling In A Low-Diversity Soil Ecosystem, Byron J. Adams, J. E. Barrett, Ross A. Virginia, Diana H. Wall Aug 2008

Decline In A Dominant Invertebrate Species Contributes To Altered Carbon Cycling In A Low-Diversity Soil Ecosystem, Byron J. Adams, J. E. Barrett, Ross A. Virginia, Diana H. Wall

Faculty Publications

Low-diversity ecosystems cover large portions of the Earth's land surface, yet studies of climate change on ecosystem functioning typically focus on temperate ecosystems, where diversity is high and the effects of individual species on ecosystem functioning are difficult to determine. We show that a climate-induced decline of an invertebrate species in a low-diversity ecosystem could contribute to significant changes in carbon © cycling. Recent climate variability in the McMurdo Dry Valleys of Antarctica is associated with changes in hydrology, biological productivity, and community composition of terrestrial and aquatic ecosystems. One of the greatest changes documented in the dry valleys is …


Effect Of Iron Source On Color And Appearance Of Micronutrient-Fortified Corn Flour Tortillas, A. T. Richins, K. E. Burton, Heather F. Pahulu, Laura K. Jefferies, Michael L. Dunn Jul 2008

Effect Of Iron Source On Color And Appearance Of Micronutrient-Fortified Corn Flour Tortillas, A. T. Richins, K. E. Burton, Heather F. Pahulu, Laura K. Jefferies, Michael L. Dunn

Faculty Publications

Iron deficiency anemia is a widespread occurrence. Consequently, iron is commonly added in cereal fortification programs. However, many iron sources cause undesirable sensory changes, especially color changes, in the food being fortified. This study evaluated the effect of different iron sources on CIE L*a*b* color values and sensory color perception in fortified corn tortillas. Corn masa flour was fortified with micronutrient premix containing vitamins, zinc, and one of eight iron compounds. Iron sources included ferrous fumarate (F), ferrous sulfate (S), ferric orthophosphate (OP), ferrous lactate (L), ferrous gluconate (G), ferric pyrophosphate (PP), sodium iron (III)-EDTA, and A-131 electrolytic iron (E), …


The Role Of Upstream Sequences In Selecting The Reading Frame On Tmrna, Allen R. Buskirk, Mickey R. Miller, David W. Healey, Jonathan D. Dewey, Stephen G. Robison Jun 2008

The Role Of Upstream Sequences In Selecting The Reading Frame On Tmrna, Allen R. Buskirk, Mickey R. Miller, David W. Healey, Jonathan D. Dewey, Stephen G. Robison

Faculty Publications

tmRNA acts first as a tRNA and then as an mRNA to rescue stalled ribosomes in eubacteria. Two unanswered questions about tmRNA function remain: how does tmRNA, lacking an anticodon, bypass the decoding machinery and enter the ribosome? Secondly, how does the ribosome choose the proper codon to resume translation on tmRNA? According to the -1 triplet hypothesis, the answer to both questions lies in the unique properties of the three nucleotides upstream of the first tmRNA codon. These nucleotides assume an A-form conformation that mimics the codon-anticodon interaction, leading to recognition by the decoding center and choice of the …


Gender Differences And Biomechanics In The 3000m Steeplechase Water Jump, Kassi R. Andersen, Bryan K. Lindsay, Iain Hunter Jun 2008

Gender Differences And Biomechanics In The 3000m Steeplechase Water Jump, Kassi R. Andersen, Bryan K. Lindsay, Iain Hunter

Faculty Publications

Since 1996, women have been competing in the 3000m steeplechase race internationally. Whenever women and men both compete in similar events with different equipment (the barriers are lower for women) consideration should be given as to how techniques should be coached differently. This study investigated the differences in water-jump technique between men and women after accounting for differences in running speed and which techniques led to maintenance of race pace through the water-jump. Eighteen men and 18 women were filmed at two major track and field meets during the 2004 season. Peak Motus 8.2 was used to digitize all seven …


Long-Distance Interval Training Following Pre-Cooling With An Ice Vest, Ronald L. Hager, Iain Hunter, Gary W. Mack, Andrew R. Tegeder Jun 2008

Long-Distance Interval Training Following Pre-Cooling With An Ice Vest, Ronald L. Hager, Iain Hunter, Gary W. Mack, Andrew R. Tegeder

Faculty Publications

This study evaluated how preparing for an interval workout, while wearing a cooling vest, affects core temperature (Tc), heart rate (HR), and interval time in long-distance runners. Nineteen male collegiate cross-country runners exercised under two different conditions: (a) wearing a Nike PreCool™ ice vest for one hour prior to the workout (30 minutes resting with the vest and 30 minutes while performing their warm-up); and (b) a control condition utilizing a traditional warm-up. Subjects performed 8 x 1000 m intervals. HR and Tc were measured prior to warm-up, immediately before the first interval, and after each interval. Tc measured before …


Comparative Phylogeography Of Codistributed Species Of Chilean Liolaemus (Squamata: Tropiduridae) From The Central-Southern Andean Range, Byron J. Adams, Pedro F. Victoriano, Juan Carlos Ortiz, Edgar Benavides, Jack W. Sites May 2008

Comparative Phylogeography Of Codistributed Species Of Chilean Liolaemus (Squamata: Tropiduridae) From The Central-Southern Andean Range, Byron J. Adams, Pedro F. Victoriano, Juan Carlos Ortiz, Edgar Benavides, Jack W. Sites

Faculty Publications

In this study, we used a recently developed supertrees method to test for shared phylogeographical signal in partially overlapping geographical ranges of lizards of the genus Liolaemus from the Andean Range in south-central Chile. We reconstruct mtDNA gene trees for three partially codistributed species (Liolaemus tenuis, L. lemniscatus and L. pictus), and our sampling effort is sufficient to allow statistical tests of shared signal between the combinations L. tenuis-L. pictus, and L. tenuis-L. lemniscatus. For both combinations, standardized maximum agreement subtrees scores showed statistically significant signal for shared pattern in regions of overlap, as evaluated by randomization tests (P < 0.001 and < 0.05, respectively). The matrix representation with parsimony tree obtained from the combination of the three different gene trees revealed concordant phylogeographical associations of all species, and was consistent with the geographical association of intraspecific haploclades with three Chilean bioclimatic zones. A multidimensional scaling analysis of several climate variables showed highly significant differences among these zones, which further suggests that they may have contributed to similar patterns of intraspecific divergence across all three species. In the mesomorphic zone in Central Chile, the species L. tenuis and L. lemniscatus may have codiverged in response to shared orogenic vicariant events, which likely predominated over climatic events associated with cycles of glacial advance and retreat. In the hygromorphic zone in southern Chile, however, glacial cycles likely predominated in structuring the phylogeographical histories of L. tenuis and L. pictus, although important ecological differences between these two caution against broad generalizations at this point.


Duplicate Gene Expression In Allopolyploid Gossypium Reveals Two Temporally Distinct Phases Of Expression Evolution, Joshua Udall, Lex E. Flagel, Dan Nettleton, Jonathan F. Wendel Apr 2008

Duplicate Gene Expression In Allopolyploid Gossypium Reveals Two Temporally Distinct Phases Of Expression Evolution, Joshua Udall, Lex E. Flagel, Dan Nettleton, Jonathan F. Wendel

Faculty Publications

Polyploidy has played a prominent role in shaping the genomic architecture of the angiosperms. Through allopolyploidization, several modern Gossypium (cotton) species contain two divergent, although largely redundant genomes. Owing to this redundancy, these genomes can play host to an array of evolutionary processes that act on duplicate genes. Results- We compared homoeolog (genes duplicated by polyploidy) contributions to the transcriptome of a natural allopolyploid and a synthetic interspecific F1 hybrid, both derived from a merger between diploid species from the Gossypium A-genome and D-genome groups. Relative levels of A- and D-genome contributions to the petal transcriptome were determined for 1,383 …


Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan Mar 2008

Comment On “Contact Conditions For The Charge In The Theory Of The Electrical Double Layer”, Douglas Henderson, L. B. Bhuiyan

Faculty Publications

Exact results in any field, including statistical mechanics, are both aesthetically pleasing and very valuable in assessing theoretical approximations.


Double-Stranded Rna-Activated Protein Kinase Pkr Of Fishes And Amphibians: Varying The Number Of Double-Stranded Rna Binding Domains And Lineage-Specific Duplications, Loubna Tazi, Stefan Rothenburg, Nikolaus Deigendesch, Madhusudan Dey, Thomas E. Dever Mar 2008

Double-Stranded Rna-Activated Protein Kinase Pkr Of Fishes And Amphibians: Varying The Number Of Double-Stranded Rna Binding Domains And Lineage-Specific Duplications, Loubna Tazi, Stefan Rothenburg, Nikolaus Deigendesch, Madhusudan Dey, Thomas E. Dever

Faculty Publications

Double-stranded (ds) RNA, generated during viral infection, binds and activates the mammalian anti-viral protein kinase PKR, which phosphorylates the translation initiation factor eIF2alpha leading to the general inhibition of protein synthesis. Although PKR-like activity has been described in fish cells, the responsible enzymes eluded molecular characterization until the recent discovery of goldfish and zebrafish PKZ, which contain Z-DNA-binding domains instead of dsRNA-binding domains (dsRBDs). Fish and amphibian PKR genes have not been described so far. Results- Here we report the cloning and identification of 13 PKR genes from 8 teleost fish and amphibian species, including zebrafish, demonstrating the coexistence of …


Enhanced Lipid Stability In Whole Wheat Flour By Lipase Inactivation And Antioxidant Retention, Devin J. Rose, Lynn V. Ogden, Michael L. Dunn, Oscar A. Pike Mar 2008

Enhanced Lipid Stability In Whole Wheat Flour By Lipase Inactivation And Antioxidant Retention, Devin J. Rose, Lynn V. Ogden, Michael L. Dunn, Oscar A. Pike

Faculty Publications

The purpose of this study was to determine the effectiveness of dry heat, steam, and microwave treatments in decreasing lipase activity, while retaining antioxidant activity, to stabilize whole wheat flour against lipid degradation during storage. Bran was heat-treated in 230-g batches using four levels (exposure times) for each of the three treatment methods. Lipase activity and antioxidant activity were quantified for all treatment combinations. None of the treatments significantly decreased antioxidant activity; the levels determined to be optimal, inasmuch as further heating did not significantly decrease lipase activity, were 25 min of dry heat, 60 sec of microwave (1000W), and …


Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy Feb 2008

Quenching Of Highly Vibrationally Excited Pyrimidine By Collisions With Co4, Jeremy A. Johnson, Andrew M. Duffin, Brian J. Hom, Karl E. Jackson, Eric T. Sevy

Faculty Publications

Relaxation of highly vibrationally excited pyrimidine (C4N2H4) by collisions with carbon dioxide has been investigated using diode laser transient absorption spectroscopy. Vibrationally hot pyrimidine (E'=40,635 cm^-1) was prepared by 248-nm excimer laser excitation, followed by rapid radiationless relaxation to the ground electronic state. The nascent rotational population distribution (J=58–80) of the 0000 ground state of CO2 resulting from collisions with hot pyrimidine was probed at short times following the excimer laser pulse. Doppler spectroscopy was used to measure the CO2 recoil velocity distribution for J=58–80 of the 0000 state. Rate constants and probabilities for collisions populating these CO2 rotational states …


Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu Feb 2008

Ozone Exposure In A Mouse Model Induces Airway Hyperreactivity That Requires The Presence Of Natural Killer T Cells And Il-17, Paul B. Savage, Muriel Pichavant, Sho Goya, Everett H. Meyer, Richard A. Johnston, Hye Y. Kim, Ponpan Matangkasombut, Ming Zhu, Yoichiro Iwakura, Rosemarie H. Dekruyff, Stephanie A. Shore, Dale T. Umetsu

Faculty Publications

Exposure to ozone, which is a major component of air pollution, induces a form of asthma that occurs in the absence of adaptive immunity. Although ozone-induced asthma is characterized by airway neutrophilia, and not eosinophilia, it is nevertheless associated with airway hyperreactivity (AHR), which is a cardinal feature of asthma. Because AHR induced by allergens requires the presence of natural killer T (NKT) cells, we asked whether ozone-induced AHR had similar requirements. We found that repeated exposure of wild-type (WT) mice to ozone induced severe AHR associated with an increase in airway NKT cells, neutrophils, and macrophages. Surprisingly, NKT cell-deficient …


Expression And Evolutionary Relationships Of The Chenopodium Quinoa 11s Seed Storage Protein Gene, Mikel Stevens, Peter J. Maughan, Daniel J. Fairbanks, Marie R. B. Balzotti, Jennifer N. Thornton, David A. Mcclellan, Eric N. Jellen, Craig E. Coleman Feb 2008

Expression And Evolutionary Relationships Of The Chenopodium Quinoa 11s Seed Storage Protein Gene, Mikel Stevens, Peter J. Maughan, Daniel J. Fairbanks, Marie R. B. Balzotti, Jennifer N. Thornton, David A. Mcclellan, Eric N. Jellen, Craig E. Coleman

Faculty Publications

Quinoa (Chenopodium quinoa Willd.) is a food crop cultivated by subsistence farmers and commercial growers on the high Andean plateau, primarily in Bolivia, Peru, and Chile. Present interest in quinoa is due to its tolerance of harsh environments and its nutritional value. It is thought that the seed storage proteins of quinoa, particularly the 11S globulins and 2S albumins, are responsible for the relatively high protein content and ideal amino acid balance of the quinoa seed. Here we report the genomic and cDNA sequences for two 11S genes representing two orthologous loci from the quinoa genome. Important features of the …


Effect Of Micronutrient Fortification On Nutritional And Other Properties Of Nixtamal Tortillas, K. E. Burton, Frost M. Steele, Laura K. Jefferies, Oscar A. Pike, Michael L. Dunn Jan 2008

Effect Of Micronutrient Fortification On Nutritional And Other Properties Of Nixtamal Tortillas, K. E. Burton, Frost M. Steele, Laura K. Jefferies, Oscar A. Pike, Michael L. Dunn

Faculty Publications

Nixtamalization is the process of steeping dried corn in hot water with calcium hydroxide (lime) with subsequent removal of all or most of the pericarp through washing. The resulting product is called nixtamal. Approximately 60% of corn tortillas in Mexico are produced from nixtamal, with the remainder prepared from nixtamalized corn flour. Nixtamal was fortified with micronutrient premix containing iron, zinc, folic acid, niacin, riboflavin, and thiamin. Premix composition followed a proposed Mexican regulation for corn flour fortification, adjusted for moisture. Effects of premix on masa adhesiveness, hardness, and pH, as well as tortilla sensory properties, stretchability, rollability, and color …