All for One and One for All! Disparity Between Overall Crew’s and Individual Rowers’ Pacing Strategies During Rowing

Purpose: This study examined individual contributions to overall pacing strategy during 2- and 5-km rowing trials in a cox-less-4 boat. Methods: A crew of 4 male rowers performed maximal-effort on-water trials over 2 and 5 km, and power output during every individual stroke was measured for each crew member. Mean overall boat and individual rower stroke power were calculated for each 25% epoch (25% of total strokes taken), and power for each individual epoch was calculated as a percentage of mean power maintained over the entire distance. The coefficient of variation was used to determine stroke-to-stroke and epoch-to-epoch variability for individual rowers and the overall boat. Results: In both trials, the overall pacing strategy consisted of a high power output in the initial 25% that decreased in the middle 50% and increased again in the final 25%. However, individual rower data indicate wide variation in individual power profiles that did not always mimic the overall boat profile. Conclusions: This study demonstrates that overall boat power profiles during 2- and 5-km rowing trials are similar to velocity profiles previously reported for individual ergometry and on-water racing events. However, this over-all profile is achieved despite considerable variation in individual rower profiles. Further research is warranted to determine the mechanisms through which individual contributions to overall pacing strategy are regulated and the effectiveness or oth-erwise of seemingly disparate individual strategies on overall performance

Alien Registration- Martin, Ida A. (Van Buren, Aroostook County)

https://digitalmaine.com/alien_docs/32232/thumbnail.jp

A High-Throughput Screening Assay for Pyruvate Carboxylase

Pyruvate carboxylase (PC) catalyzes the conversion of pyruvate to oxaloacetate (OAA), an important metabolic reaction in a wide range of organisms. Small molecules directed against PC would enable detailed studies on the metabolic role of this enzyme and would have the potential to be developed into pharmacological agents. Currently, specific and potentsmall molecule regulators of PC are unavailable. To assist in efforts to find, develop, and characterize small molecule effectors of PC, a novel fixed-time assay has been developed based on the reaction of OAA with the diazonium salt, Fast Violet B (FVB), which produces a colored adduct with an absorbance maximum at 530 nm. This fixed time assay is reproducible, sensitive and responsive to known effectors of Rhizobium etli PC, Staphylococcus aureus PC, and Listeria monocytogenes PC, and is highly amenable to high-throughput screening. The assay was validated using a plate uniformity assessment test and a pilot screen of a library of 1280 compounds. The results indicate that the assay is suitable for screening small molecule libraries to find novel small molecule effectors of PC

Osteopontin: an early innate immune marker of Escherichia coli mastitis harbors genetic polymorphisms with possible links with resistance to mastitis

<p>Abstract</p> <p>Background</p> <p>Mastitis is the most important disease in dairy cows and it causes significant lost of profit to producers. Identification of the genes, and their variants, involved in innate immune responses is essential for the understanding of this inflammatory disease and to identify potential genetic markers for resistance to mastitis. The progeny of dairy cows would benefit from receiving favourable alleles that support greater resistance to infection, thus reducing antibiotic use. This study aims to identify a key gene in the innate immune response to mastitis, led us to evaluate its genetic association with somatic cell score (SCS), which is an indicator of clinical mastitis, and to evaluate its impact on other traits related to milk production.</p> <p>Results</p> <p>The osteopontin transcript (<it>SPP1</it>) was identified in the somatic cells from cows experimentally infected with <it>Escherichia coli</it>. By selecting bulls with extreme estimated breeding values (EBVs) for SCS, which is an indicator of mammary gland health, four DNA polymorphisms in the <it>SPP1 </it>genomic sequence were found. Statistical analysis revealed that the SNP <it>SPP1c.-1301G>A </it>has an impact on EBV for SCS (<it>P </it>< 0.001) Using an allele substitution model, <it>SPP1c.-1251C>T</it>, <it>SPP1c.-430G>A</it>, and <it>SPP1c.*40A>C </it>have an impact on SCS whereas <it>SPP1c.-1301G>A </it>has an effect on the EBVs for milk yield (second and third lactations), fat and protein percentages (all three lactations). Analysis revealed statistically significant differences between haplotype groups at a comparison-wise level with sire EBVS for SCS for the first (<it>P </it>= 0.012), second (<it>P </it>< 0.001), and third (<it>P </it>< 0.001) lactations.</p> <p>Conclusion</p> <p>This study reports the link between DNA polymorphisms of <it>SPP1</it>, the number of milk immune cells and, potentially, the susceptibility to mastitis. These SNPs were identified by <it>in silico </it>search to be located in transcription factor recognition sites which factors are presumably involved in the Th1 immune response and in the Th2 regulation pathway. Indeed, one SNP abolished the SP1 recognition site, whereas another SNP affected the transcription binding factor IKAROS. All together, these findings support the genetic potential of these variants in terms of selection for the improvement of mastitis resistance in dairy cows.</p