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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

Neuromuscular Adaptations Following Training and Protein Supplementation in a Group of Trained Weightlifters

Taber, Christopher B., Carroll, Kevin, DeWeese, Brad H., Sato, Kimitake, Stuart, Charles, Howell, Mary, Hall, Kenton, Bazyler, Caleb D., Stone, Michael H. 19 April 2018 (has links)
The purpose of this study was to examine the effects of a recovery supplement compared with a placebo on muscle morphology in trained weightlifters. Vastus lateralis and muscle fiber cross sectional area of type I and type II fibers were compared between groups using a series of 2 × 2 (group × time) repeated measure ANOVAs. Both groups on average improved cross-sectional area of the vastus lateralis, type I and type II muscle fibers from pre-to-post but individual response varied within both groups. Greater magnitude of changes in type I and type II muscle fibers were observed for the placebo group but not for vastus lateralis cross sectional area. Additionally, subjects were divided into large and small fiber groups based on combined fiber size at the start of the investigation. These findings indicate that the recovery supplement utilized provided no greater effect compared with a placebo in a 12-week block periodization protocol in trained weightlifters. The primary determinate of fiber size changes in the study was determined to be the initial fiber size of muscle fibers with larger practical changes observed in the small fiber group compared with the large fiber group in type I, II, and ultrasound cross-sectional area (CSA).
252

Efeito da suplementação de fonte inorgânica de ferro no perfil metaloproteômico da geleia real produzida por abelhas Apis mellifera L.

Araújo, Wellington Luiz de Paula January 2018 (has links)
Orientador: Ricardo de Oliveira Orsi / Resumo: O objetivo do presente estudo foi avaliar o efeito de suplementação com fonte de ferro inorgânico na qualidade da geleia real produzida por abelhas A. mellifera, por meio de análises proteômicas. Foram utilizadas 12 colônias de abelhas A. mellifera africanizadas, alimentadas com xarope de açúcar (proporção de 1:1 de água e açúcar cristal) suplementado ou não com sulfato ferroso heptahidratado (contendo 20% de ferro), nas concentrações de 0, 25, 50 e 100 mg L-1. A produção de geleia real foi realizada por meio da técnica de transferência de larvas, colhida, armazenada em vials estéreis e mantidas sob congelamento. Eletroforese bidimensional (2D-PAGE) foi usada para fracionamento das proteínas da geleia real e o ferro quantificado por técnica de espectroscopia de absorção atômica de chama (FAAS), com identificação das proteínas por Espectrometria de massas com ionização por eletrospray (ESI-MS/MS). Os resultados foram avaliados por ANOVA, seguido do teste de Tukey para verificar diferenças entre as médias (P<0,05). Observou-se que a suplementação da dieta com o mineral ferro afetou o teor proteico e o número de spots em quase todos os tratamentos e meses analisados. Observa-se ainda que a dieta contendo 100 mg L-1 de Fe apresentou maior numero de spots contendo este mineral, bem como no abdome das abelhas. As principais proteínas contendo Fe foram classificadas como do grupo MRJPs (Major Royal Jelly Proteins). Os resultados encontrados mostram que o ferro influência na qualidad... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
253

Declining populations in changing environments: adaptive responses, genetic diversity, and conservation

Avril M Harder (9722096) 15 December 2020 (has links)
<p>Many salmonid populations are supported through captive breeding programs in which hatchery production supplies fish for reintroduction or supplementation efforts. In Lake Champlain, Atlantic salmon (Salmo salar) are the subject of a reintroduction effort that is complicated by the occurrence of thiamine (vitamin B1) deficiency in adult salmon returning to spawn. This deficiency results in high offspring mortality rates that must be mitigated by hatchery interventions (reviewed in Chapter 1). I used an experimental transcriptomics approach coupled with survival analyses to assess genetic variation in thiamine deficiency outcomes (i.e., survival at the family level) and identified candidate genes that may comprise a putatively adaptive response to selection imposed by thiamine deficiency (Chapter 2). Using sequence data from this study, I next compared patterns of genetic variation in the Lake Champlain population against two other populations to identify signatures of selection associated with hatchery rearing environment and differences in life history strategies (Chapter 3). Finally, I surveyed salmonid populations for density-dependent effects of adult spawning density on per capita fitness and found that in many cases, hatchery releases can contribute to decreased individual fitness. Using genotype data for returning adults in multiple populations, I also tested for reductions in effective population size (Ne) associated with hatchery supplementation and describe how increasing hatchery contribution to a population decreases Ne (Chapter 4). Together, my results demonstrate the powerful influences of hatchery supplementation on salmonid populations and suggest that specific modifications to hatchery practices can limit negative impacts of captive breeding on population genetic and demographic characteristics.</p>
254

Exogenous ketone supplementations in sports: Metabolic, physical, and cognitive effects

Dubbel, Sofhie January 2020 (has links)
No description available.
255

Iron Deficiency and Iron Deficiency Anemia: Implications and Impact in Pregnancy, Fetal Development, and Early Childhood Parameters

Means, Robert T. 01 February 2020 (has links)
A normal pregnancy consumes 500–800 mg of iron from the mother. Premenopausal women have a high incidence of marginal iron stores or iron deficiency (ID), with or without anemia, particularly in the less developed world. Although pregnancy is associated with a “physiologic” anemia largely related to maternal volume expansion; it is paradoxically associated with an increase in erythrocyte production and erythrocyte mass/kg. ID is a limiting factor for this erythrocyte mass expansion and can contribute to adverse pregnancy outcomes. This review summarizes erythrocyte and iron balance observed in pregnancy; its implications and impact on mother and child; and provides an overview of approaches to the recognition of ID in pregnancy and its management, including clinically relevant questions for further investigation.
256

Can a Model Predictive of Vitamin D Status Be Developed From Common Laboratory Tests and Demographic Parameters?

Peiris, Alan N., Bailey, Beth A., Guha, Bhuvana N., Copeland, Rebecca, Manning, Todd 01 September 2011 (has links)
Objectives: Vitamin D deficiency is highly prevalent and has been linked to increased morbidity and mortality. There has been an increase in testing for vitamin D with a concomitant increase in costs. While individual factors are significantly linked to vitamin D status, prior studies have not yielded a model predictive of vitamin D status or 25(OH)D levels. The purpose of this investigation was to determine if a prediction model of vitamin D could be developed using extensive demographic data and laboratory parameters. Methods: Patient data from 6 Veterans Administration Medical Centers were extracted from medical charts. Results: For the 14,920 available patients, several factors including triglyceride level, race, total cholesterol, body mass index, calcium level, and number of missed appointments were significantly linked to vitamin D status. However, these variables accounted for less than 15% of the variance in vitamin D levels. While the variables correctly classified vitamin D deficiency status for 71% of patients, only 33% of those who were actually deficient were correctly identified as deficient. Conclusion: Given the failure to find a sufficiently predictive model for vitamin D deficiency, we propose that there is no substitute for laboratory testing of 25(OH)D levels. A baseline vitamin D 3 daily replacement of 1000-2000 IU initially with further modification based on biannual testing appears to factor in the wide variation in dose response observed with vitamin D replacement and is especially important in high-risk groups such as ethnic minorities.
257

THE USE OF NUTRITIONAL PROGRAMMING AND DIPEPTIDE SUPPLEMENTATION AS A MEANS OF MITIGATING THE NEGATIVE EFFECTS OF PLANT PROTEIN AND IMPROVING THE GROWTH OF FISH FED WITH PLANT-BASED DIETS

Molinari, Giovanni Settle 01 September 2020 (has links)
Currently aquaculture is the largest growing food sector in the world, however, its future growth is limited by its heavy reliance on fishmeal (FM). Overfishing of wild marine fish stocks used for FM is putting too much pressure on the stocks, making FM unsustainable as a dominant protein source as aquaculture continues to grow. Plant proteins (PP) are an ideal alternative to FM because of their wide availability and relatively low cost. Soybean meal (SBM) is the most commonly used PP in aquaculture, but its inclusion in feeds is limited due to reduced digestibility and the presence of antinutritional factors ultimately leading to a reduced growth performance of fish that are fed with the SBM-based diet. Therefore, the goal of this thesis was to mitigate the negative effects of PP and improve the growth of fish fed with a PP-based diet, utilizing SBM as our PP in feeds. Three feeding trials were conducted to test the efficacy of 3 approaches towards improving the use of PP in fish. The first trial (Chapter 2), tested the effect of nutritional programming (NP) on the utilization of SBM in zebrafish (Danio rerio). NP is the theory that an organism can be ‘programmed’ to better utilize a dietary component by being exposed to that component in its early life stages. This study also tested the effect of NP through the broodstock by exposing the broodstock to SBM for 4 weeks prior to breeding. In addition, a combination of both programming techniques was also tested. The results found that neither of the programming techniques had a significant effect on the growth performance of the zebrafish. Among the two groups from the programmed broodstock, the group that also received early stage NP had a significantly higher expression of PepT1, a di- and tri- peptide transporter. Also, the dual programmed group had the highest length-to-width ratio of the distal villi among groups that were fed SBM, which signifies an increase in surface area for nutrient absorption in the intestine. The findings from this study suggest that early stage NP may increase the absorption of nutrient from PP-based feeds within the intestine. The second feeding trial (Chapter 3), utilized the supplementation of health-promoting dipeptides to improve the use of SBM-based feeds for zebrafish. The three dipeptides used in this study were alanyl-glutamine, carnosine, and anserine. The five groups in this study consisted of three groups receiving an SBM-based diet with one of the dipeptides supplemented into it, a (-) Control group receiving a non-supplemented SBM-based diet, and a (+) Control group receiving a FM-based diet. Both the alanyl-glutamine and carnosine supplemented groups experienced a significantly higher weight gain compared to the (-) Control group. In addition, the alanyl-glutamine supplemented group had a significantly higher length-to-width ratio of the intestinal villi and, had a numerically higher expression of both nutrient absorption genes measured, PepT1 and fabp2, compared to the (-) Control group. This finding suggests that the supplementation of alanyl-glutamine into SBM-based diets may improve the intestinal absorptive capacity of the fish fed with the SBM. The results from this study also support the use of both alanyl-glutamine and carnosine supplementation as a means of improving the growth performance of fish fed with a SBM-based diet. The third feeding trial (Chapter 4), was conducted on largemouth bass (LMB) (Micropterus salmoides). This study also focused on NP as a means of improving the utilization of dietary SBM, similar to Chapter 2. In this study, live feed was used as a vector to program the larval LMB to SBM. The programmed group in this study received Artemia nauplii that were enriched with a SBM solution, during the larval stage. The bass were then fed with a FM-diet for 7 weeks, before being reintroduced to SBM for the final 6 weeks of the study (PP-Challenge). The programmed LMB experienced a significantly higher weight gain compared to the non-programmed fish also undergoing the PP-Challenge, and achieved a weight gain similar to that of the LMB that were being fed with an FM-diet. In addition, the programmed LMB had significantly longer distal villi and a higher length-to-width ratio of the villi, compared to the non-programmed group. The findings from this study support the use of live feed as a vector for NP and improving the growth performance of a carnivorous aquaculture species fed with a SBM-based diet. The overall findings from these studies suggest that both NP and dipeptide supplementation are feasible means of improving the utilization of SBM in fish. The mechanism behind NP seems to lie in the intestine. In both zebrafish and LMB, NP was found to reduce the inflammatory impact on the intestine and increase the surface area for absorption of the intestinal villi. The supplementation of alanyl-glutamine had similar effects on the intestine as NP and improved the growth performance of zebrafish. The observations from these studies seem to point to mitigating the negative effects of SBM on the intestine as the key to improving the growth performance of fish fed with a SBM-based diet.
258

Modulation of the Nutritional Context and Early Experience as New Tools to Increase the Use of Medusahead (Taeniatherum caput-medusae ssp. asperum) by Grazing Sheep

Montes, Juan J. 01 May 2016 (has links)
The success of medusahead (Taeniatherum caput-medusae ssp. asperum) as an invasive exotic grass in the western US is attributed in part to its low palatability. The nutritional context where medusahead grows can be modulated by the use of supplements that increase herbivores’ preference for unpalatable feeds. Additionally, positive experiences early in life (with mother, with supplements) can have long-life influences on preference for unpalatable feeds. To test the influence of the nutritional context on medusahead intake, ewes grazed with their lambs during summer of 2013 on medusahead-infested rangeland with (Treatment) or without (Control) the daily provision of an energy-rich supplement. To test for the effect of experience early in life at grazing medusahead on use of this weed later in life, lambs that grazed with their mothers during 2013 (Experienced) were exposed to medusahead (in pens and during grazing) as yearlings during summer of 2014 along with inexperienced (Control) animals. To better understand the unpalatability of medusahead, the fermentation kinetics of medusahead at different phenological stages and particle sizes was assessed. Ewes grazing with their lambs showed low use of medusahead (5% of the grazing events recorded), even when supplemented. Nevertheless, medusahead use increased across the grazing period and utilization was similar to medusahead abundance in the plant community. Use of medusahead by nursing lambs was correlated with that observed by their mothers and lambs utilized medusahead to the same extent either before or after weaning. Yearlings in pens showed low intake of medusahead and a cyclic pattern of intake across days. However, experienced yearlings displayed a more even intake of medusahead across days and a greater gain-to-feed ratio than Control yearlings. All yearlings showed low to nil use of medusahead during grazing. Medusahead had lower fermentation rates than alfalfa hay and fermentation rates declined with plant maturity. Organic matter digestibility for medusahead declined as particle size of the substrate increased, a relationship that explains the low palatability of the weed. These results provide the foundation for grazing treatments aimed at reducing the abundance of the weed or at preventing its spread in rangelands with different levels of medusahead infestations.
259

Vitamin D Deficiency and Supplemental Use in Pregnancy: A Systematic Review and Meta-Analysis

Rogers-Kelly, Christine 04 May 2018 (has links)
Vitamin D inadequacy is highly prevalent among pregnant women worldwide. Inadequacy or deficiency of vitamin D can lead to adverse outcomes during pregnancy such as pre-eclampsia, gestational diabetes, and caesarian section. A systematic review and meta-analysis were conducted to examine the effectiveness of vitamin D supplementation on serum vitamin D status during pregnancy in randomized controlled trials (RCTs). A search was conducted in PubMed, Scopus, ProQuest, EBSCO, Cochrane CENTRAL Database of Controlled Clinical Trials, PsycINFO, CINAHL, and Google Scholar, in addition to searching reference lists in published reviews. A comprehensive list of RCTs of vitamin D status and supplemental use in pregnancy was compiled. The random effects model was used to determine a summary effect size using pre/post means and standard deviations of serum vitamin D levels from intervention and control groups. Sixteen RCTs indicated a large effect size (d = .849, 95% CI .607 – 1.001, p < .001). Serum vitamin D concentration at delivery was higher with vitamin D supplementation, and thereby the metabolic outlook was favorable for the mother and newborn. Heterogeneity of the meta-analysis was significant (Q = 344.418, p < .001); the I-squared statistic showed moderate heterogeneity (61.89%), which warranted subgroup analysis to identify possible sources of variation among the studies. Moderators for subgroup analysis included vitamin D dosages, use of a placebo, use of multivitamins in addition to vitamin D, duration of interventions, age, low or adequate baseline vitamin D status, trimester when supplementation was started, country where the RCT was conducted (USA/UK/AUS versus other countries), and blinded versus non-blinded RCTs. Subgroup analysis only demonstrated a significant impact on heterogeneity from the trimester moderator (p < .001). Women who began vitamin D supplementation during the first trimester had a higher effect size and improved vitamin D status compared to those who began supplementation in the second or third trimester. Since pregnant women with vitamin D inadequacy or deficiency are more susceptible to complications, routine examination of vitamin D status should be conducted in pregnant women.
260

The Effects of a Combined Supplementation of Creatine and Sodium Bicarbonate on Repeated Sprint Performance

Barber, James Jeremy, Hagobian, Todd, McGaughey, Karen, McDermott, Ann Yelmokas, Olmstead, Jennifer Davis 01 September 2010 (has links) (PDF)
Abstract The Effects of a Combined Supplementation of Creatine and Sodium Bicarbonate on Repeated Sprint Performance James Jeremy Barber There is well-established research that suggests both creatine and sodium bicarbonate are effective ergogenic aids. However, only one published study has examined the combined effects of creatine and sodium bicarbonate. The primary purpose of this study was to determine if a combined supplementation of creatine monohydrate and sodium bicarbonate would further enhance the well-documented effects of creatine supplementation alone on repeated sprint performance. Thirteen healthy and fit males (Mean age = 21.15 ± 0.65 years and mean VO2 max = 66.72 ± 5.78) participated in this experimental study using a double-blinded crossover study design in which each subject was used as his own control. All subjects completed 3 conditions, followed by a 3-week washout period between each condition: 1) Placebo (Pl; 5 g maltodextrin + 0.5 g/kg maltodextrin), 2) Creatine (Cr; 5 g + 0.5 g/kg maltodextrin), and 3) Creatine plus sodium bicarbonate (Cr+Sb; 5g + 0.5 g/kg sodium bicarbonate). Each condition was a 2-day supplementation. In the morning after each supplementation, peak power, RPP, mean power, RMP, fatigue index, and perceptions of fatigue and GI distress were assessed during six 10-second repeated Wingate tests. Blood bicarbonate, pH, and lactate were measured 5 minutes before testing and immediately after the last Wingate sprint. The main findings were; 1) Cr+Sb produced 7% greater relative peak power and 4.6% greater peak power values than placebo, and 2) Cr+Sb demonstrated the greatest attenuation of decline in relative peak power over six repeated sprints. However, in contrast to our hypotheses, no benefits from either supplementation were observed for relative mean power, fatigue index, and perception of fatigue. Considering that this current study found benefits from combining creatine and sodium bicarbonate, it suggests that combining the supplements may improve repeated sprint performance. Future research on a greater sample size, a specific athletic population, various exercise modes, and comparing results with a sodium bicarbonate alone supplementation would be beneficial in determining if this combined supplementation is worthwhile.

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