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There has been much consideration over whether exogenous ketone bodies have the capacity to enhance exercise performance through altered substrate metabolism. This systematic review aimed to determine the effects of both ketone precursors and monoesters on endurance exercise performance. A systematic search was conducted in PubMed, SPORTDiscus, and CINAHL for randomized controlled trials investigating endurance performance outcomes in response to ingestion of a ketone supplement compared to a nutritive or non-nutritive control in humans. A meta-analysis was performed to determine the standardized mean difference between interventions using a random-effects model. Hedges’ g and 95% confidence intervals (CI) were reported. The search yielded 569 articles, of which 8 were included in this review (80 participants; 77 men, 3 women). When comparing endurance performance amongst all studies, no significant differences were found between ketone and control trials (Hedges g=0.136; 95% CI, -0.195, 0.467; p=0.419). Sub-analyses based on type of endurance tests showed no significant differences in time to exhaustion (Hedges g=-0.002; 95% CI, -0.312, 0.308; p=0.989) or time trial (Hedges g=0.057; 95% CI, -0.282, 0.395; p=0.744) values. Based on these findings, exogenous ketone precursors and monoesters do not significantly improve endurance exercise performance. While all studies reported an increase in blood ketone concentrations after ingestion, ketone monoesters appear to be more effective at raising concentrations than precursors.

Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: A 240-day growth study was conducted to determine the suitability of soybean meal (SBM) as an alternative protein source to fish meal (FM) in the diet of commercially produced South African abalone (Haliotis midae). The suitability of SBM was determined by a close evaluation of the following key factors: feed water stability, morphological impact on the abalone intestine and the effect on the growth performance of abalone. The study was comprised of two phases: a fish meal replacement phase (Phase A) and an enzyme treatment phase (Phase B). Diets used in Phase A consisted of a control fish meal diet (Control=22%FM, 0%SBM), a fish meal-soybean meal diet (FMSBM=20%FM, 15%SBM), a soybean meal-low diet (SBMlow=0%FM, 15%SBM) and a soybean meal diet (SBM=0%FM, SBM30%). In Phase B, the FM diet and SBM diet were used as basal diets (FME0 and SBME0). These diets were then treated with three commercial enzyme products, namely, a β- glucanase (FME1 and SBME1), xylanase (FME2 and SBME2) and α-D-galactosidase (FME3 and SBME3). Subsequently, all three enzymes were combined to make two treatments (FME123 and SBME123). With regard to the gut morphology and growth trials, a thirteenth energy enhanced commercial animal protein-free diet (ECO) was used. In Phase A (fish meal replacement), the findings revealed that water stability did not differ significantly between treatments. In Phase B (enzyme treatment) however, the water stability of β- glucanase treated feeds was significantly lower than that of the control FM diet. It was also observed that in comparison to the control FM diet, soybean meal based diets have a significantly greater effect on intestinal morphology. With reference to Phase A (fish meal replacement), by the end of the 240 day growth trial period, it was evident that animals fed on the commercial (ECO) diet were significantly heavier than those given the control FM diet. With regard to final length in mm, feed conversion ratio (FCR) and specific growth rate (SGR) for mass and length, no differences between the treatments were noted. It was also found that the condition of the ECO fed animals was significantly better in comparison to the other treatment fed animals. No significant differences were observed between the FM and three FMreplaced diets however. With reference to Phase B (enzyme treatment), it was noted that once again, after the 240 day period, abalone fed on the ECO diet were significantly heavier in terms of their final weight when compared to those fed on the other diets. As in Phase A, no differences in FCR and SGR for mass and length were observed. Measurements of the animals’ final length (as observed on day 240) revealed that those fed on the ECO diet were significantly longer than those given the FME1, SBME1 and SBME3 diets. At the end of the trial, abalone fed on the ECO diet were also in significantly better condition than those fed on the SBM, FME3 and FME123 diets. In terms of production performance, no significant difference was found between the SBM diets and FM diets and enzyme supplementation did not significantly increase the production performance either. The results of this study therefore show that SBM has great potential to be used as a FM-replacement diet. The improved performance of the ECO diet was expected due to its energy content. / AFRIKAANSE OPSOMMING: ‘n Groeistudie is gedoen met die perlemoen (Haliotis midae) oor ʼn tydperk van 240 dae om die geskiktheid van sojaboonoliekoek (SBM) as ‘n alternatiewe proteïenbron ter vervanging van vismeel (FM) in die rantsoen te evalueer. Geskiktheid van SBM is getoets aan die hand van waterstabiliteit van voer, morfologie van die spysverteringskanaal en die invloed daarvan op groei van die perlemoen. Die studie het uit twee fases bestaan naamlik ‘n vismeel (FM) vervangingsfase (Fase A) gevolg deur ‘n ensiem behandelingsfase (Fase B). Die diëte wat gebruik was sluit in ’n Kontrole dieet wat slegs vismeel as proteïenbron bevat (Kontrole = 22%FM, 0%SBM), ‘n 2de dieet wat beide vismeel en sojaboonoliekoekmeel bevat (FMSBM =20%FM, 15% SBM), ‘n 3de dieet wat ‘n lae vlak sojaboonoliekoekmeel bevat (SBMlow =0%FM, 15%SBM) en 4de dieet met ʼn hoër sojaboonoliekoek vlak (SBM = 0%FM, 30% SBM). Die basale diëte van Fase B was dieselfde as die FM en SBM diëte van Fase A (FME0 en SBM0) met die verskil dat dit met kommersiële ensieme behandel is. Die onderskeie behandelings was gedoen met β-glukanase (FME1 en SBME1), xylanase (FME2 en SBME2) en α-D-galactosidase (FME3 en SBME3) asook ‘n kombinasie van die drie ensieme (FME123 en SBME123). ‘n Addisionele behandeling bestaande uit ‘n kommersiële diereproteïenvrye dieet (ECO) is as bygevoeg as kontrole vir die histologie gedeelte van die proef. Tydens Fase A is gevind dat waterstabiliteit van die onderskeie diëte nie betekenisvol verskil het nie. Tydens Fase B het ensiembehandeling met β-glukanase egter aanleiding gegee tot betekenisvolle laer waterstabiliteit van FME1 en SBME1 diëte in vergelyking met die FM dieet. Histologiese ontledings het getoon dat die SBM diëte ‘n groter negatiewe effek op die morfologie van die spysverteringkanaal gehad het as die kontrole FM dieet. Fase A het getoon dat die ECO dieet beter groeiresultate opgelewer het as die FM dieet, in terme van liggaamsmassa en kondisiefaktor van die perlemoen. Finale skulplengte (mm), voeromsetverhouding (VOV) en spesifieke groeitempo (SGT) vir massa en lengte was egter nie betekenisvol verskillend vir enige van die behandelings nie. Geen betekenisvolle verskille is ook gevind tussen die FM en enige van die FM vervangingsdiëte nie. Resultate vir Fase B het getoon dat diere wat die ECO dieet gevoer is betekenisvol swaarder was as diere wat ander voere gevoer is. Geen betekenisvolle verskille is waargeneem vir VOV en SGT van massa en lengte nie. Finale lengte van die diere wat ECO gevoer is was langer as die van die FME1, SBME1 en SBME3 diëte. Die ECO diere het ook in betekenisvol beter kondisiefaktor vertoon as diere wat SBM, FME3 en FME123 diëte gevoer is. Geen betekenisvolle verskille in produksie parameters is opgemerk tussen die FM en SBM diëte nie en die toevoeging van ensieme het ook nie ‘n betekenisvolle invloed gehad nie. Die gevolgtrekking is dat sojaboonoliekoekmeel suksesvol aangewend kan word vir die vervanging van vismeel in perlemoen diëte.

Fingernail samples are analyzed in forensic casework to determine the source of the nail and/or to recover a foreign profile from beneath the nail. When extracting from a fingernail sample, it is possible to recover deoxyribonucleic acid (DNA) of the nail donor from within the nail and from the surface of the nail; similarly, foreign DNA may also be present on and recovered from the nail surface. When attempting to recover the latter, fingernail samples present particular problems. Often, the foreign component is masked by the greater mass of donor DNA present within and on the nail sample. This masking effect is exacerbated by the use of proteinase K (PK) in DNA extractions, as PK, with an average of 200 cut sites per keratin molecule, is capable of breaking open the keratin matrix of the nail and exposing the nail DNA intercalated in the matrix. Directly extracting nail clippings, in contrast to swabbing or scraping, would further introduce nail DNA when using proteinase K. The present study explores whether utilizing other proteases (ZyGEM, Acrosolv, and Factor Xa) with fewer cut sites than PK or direct lysis methods (IGEPAL® CA-630 and MAWI iSWABTM-ID) would minimize recovery of nail DNA from within the nail and thus mitigate the masking effect often seen with fingernail samples. The endogenous DNA extraction efficiency of each suggested method was compared with the manufacturer’s standard QIAGEN QIAamp® DNA Investigator extraction protocol for hand-washed and/or laboratory-cleaned nails. The extraction results from the hand-washed nails demonstrate variability both within samples from the same donor and between donors. In contrast to previously published literature, a comparison of the results between the hand-washed and cleaned nails suggests that much of the endogenous DNA recovered from fingernail samples is derived from DNA on the surface rather than from within the nail. QIAamp® extraction with the inclusion of dithiothreitol (DTT) recovered significantly more DNA (0.845 ± 0.651 nanograms of DNA per milligram of nail [ng DNA/mg nail]; p = 0.0045) than the same protocol without DTT (0.278 ± 0.253 ng DNA/mg nail). IGEPAL® recovered the least endogenous DNA (0.005 ± 0.012 ng DNA/mg nail) from the nail. The ZyGEM extraction recovered the second lowest amount (0.163 ± 0.161 ng DNA/mg nail) and both the Acrosolv (0.546 ± 0.607 ng DNA/mg nail) and MAWI’s iSWABTM-ID (0.681 ± 0.780 ng DNA/mg nail) methods recovered more DNA than the QIAamp® protocol without DTT. An assessment of the electropherograms resulting from cleaned fingernails across all extraction methods for one donor showed that both IGEPAL® and MAWI failed to recover a complete profile, whereas the remaining methods were able to recover complete profiles of the nail donor. An assessment of donor variability found variations in terms of endogenous nail DNA recovery. Fingernails were also spiked with blood, saliva, or semen to assess the recovery of foreign DNA. The extractions of the spiked nail samples demonstrate variability across all samples, owing, to some degree, to inconsistencies of sample preparation. IGEPAL®’s inability to recover complete foreign profiles suggests that the method may not be viable for extraction of fingernail samples. Conversely, the ZyGEM, Acrosolv, and MAWI extraction methods demonstrate potential as alternative extraction methods for fingernail samples and would benefit from additional experimentation.

There is a need in the cotton industry for cultivars with enhanced lint yield potential and high-quality fiber properties. Indole-3-acetic acid (IAA) is a phytohormone that is predominantly responsible for cell elongation and required for primary elongation in cotton fiber development. An increase in IAA at specific fiber developmental stages may promote increased lint percent and longer fibers. Objectives of this research project were to determine how exogenous applications in a field environment affect fiber traits and lint yield potential in diverse genotypes. The first study examined application methods to ascertain the optimal placement and timing of IAA. The second study focused on genotype reactions to elevated levels of IAA. Results indicate exogenously applied IAA provided a potential yield increase but did not improve fiber length. Further research needs to be conducted to effectively understand IAA’s role in fiber development and establishing protocols for maximizing IAA potential in a field environment.

archives@tulane.edu / People living through changes in their surroundings react to it unexpectedly. Exogenous political, economic and legal changes impact individual behavior in an unpredictable manner. This dissertation uses three papers to give evidence of exogenous shocks affecting individual behavior. First, I study the impact of an economic change. Using business cycle indicators, I show that a change in the employment status of parents causes them to invest higher time with their children instead of exploring new job opportunities in the early months of unemployment. The short term impact of unemployment is favorable for child development even though literature has shown that long term unemployment is detrimental to child well-being. Second, I explore the impact of a spillover of a policy intended to save energy. The Daylight Savings Time was implemented during the World Wars to conserve energy. Over the decades, its impact on energy conservation has diminished. My research shows that there are clear evidences of serious disruption in daily lives of those subjected to the clock change twice a year, causing higher stress and lower sleep in the early weeks of the time change. Third, I study the legalization of medical marijuana on consumption of marijuana and alcohol patterns, as well as criminal behavior among those subjected to it. The results show that even though there is a slight increase in marijuana and alcohol consumption among adults, there is no evidence to support that it encourages teenagers to explore marijuana consumption. There is also no evidence of any change in criminal behavior. / 1 / Sanjukta Basu

Interactions between non-starch polysaccharide (NSP) level, dietary lipid type, exogenous carbohydrase enzymes and irradiation were investigated. Ten treatment diets were fed to broilers in a performance and digestibility trial. Eight of the diets contained high levels of NSP, achieved by a high barley inclusion of 55% of the diet. Four of the treatments made use of non-irradiated barley, whereas the barley included in the other four diets was irradiated. By adding either 10% soya oil or yellow grease (fat) as the lipid source, sub groups were created which differed in fatty acid profile. Lastly, these treatments were further subdivided by supplementing one of the two diets from each subgroup with a commercially available combination of exogenous carbohydrase enzymes consisting of cellulases, xylanases and â - glucanases (Roxazyme G at 150 g/ton). The two control diets were based on maize (low NSP diets) with either soy oil or yellow grease. The high NSP diets had significantly lower (P<0.05) apparent metabolisable energy (AME) and lipid digestibility values than the low NSP diets. Lipid digestibility and AME values were also significantly lower (P<0.05) for diets containing yellow grease compared to soya oil. The birds that received yellow grease performed worse in terms of growth, feed intake and feed conversion ratio (FCR) than the oil-containing diets. These trends were evident throughout all treatments, although not always significant. The addition of carbohydrase to diets based on barley improved the dietary lipid digestibility and AME values. Significant improvements (P<0.05) in bird performance were noted for the barley diets with the yellow grease. Pre-irradiation of barley significantly increased (P<0.05) the AME value of diets, and improved lipid digestibility of the fat-containing treatment. The simultaneous combination of carbohydrase supplementation and barley irradiation proved to have an additive positive effect on feed quality and bird performance. For all treatments this combination improved the barley based diets to such an extent that it performed equally or significantly better (P<0.05) than its maize based counterpart. The irradiated barley-yellow grease based diets showed a more pronounced benefit with the addition of carbohydrase enzymes to the feed (P<0.05). / Dissertation (MSc(Agric))--University of Pretoria, 2008. / Animal and Wildlife Sciences / unrestricted

We explored the role that exogenous and endogenous competitors for attention play in infants’ abilities to encode and retain information over a 6‐month period. Sixty‐six children visited the laboratory at 15 months, and 32 returned for a second visit at 21 months. Children observed models of conventional‐ relation and enabling‐relation action sequences. Half the children were distracted by a “Mister Monkey” mechanical toy during the conventional‐relation sequence, while the other half was distracted during the enabling‐relation sequence. The Early Childhood Behavior Questionnaire indexed endogenous factors at both ages. Immediate postmodel production of target actions indexed encoding efficiency, and 6‐month production of target actions indexed long‐term recall. The exogenous distracter impacted encoding efficiency (i.e., immediate recall), but not long‐term recall. Endogenous factors (i.e., temperament) were primarily associated with long‐term recall. Of special interest was our finding that endogenous factors, especially surgency, moderated the effect of the exogenous distracter. It appears that when learning conventional‐relation sequences in the presence of exogenous distracters, surgency mobilizes attentional resources toward the learning objective; however, when learning enabling‐relation sequences under the same conditions, surgency either boosts the saliency of the distracters or boosts children’s susceptibility to them.

In the well known SIR endemic model, the infection-free steady state is globally stable for R0 < 1 and unstable for R0 > 1. Hence, we have a forward bifurcation when R0 = 1. When R0 > 1, an asymptotically stable endemic steady state exists. The basic reproduction number R0 is the main threshold bifurcation parameter used to determine the stability of steady states of SIR endemic models. In this thesis we study extensions of the SIR endemic model for which a backward bifurcation may occur at R0 = 1. We investigate the biologically reasonable conditions for the change of stability. We also analyse the impact of di erent factors that lead to a backward bifurcation both numerically and analytically. A backward bifurcation leads to sub-critical endemic steady states and hysteresis. We also provide a general classi cation of such models, using a small amplitude expansion near the bifurcation. Additionally, we present a procedure for projecting three dimensional models onto two dimensional models by applying some linear algebraic techniques. The four extensions examined are: the SIR model with a susceptible recovered class; nonlinear transmission; exogenous infection; and with a carrier class. Numerous writers have mentioned that a nonlinear transmission function in relation to the infective class, can only lead to a system with an unstable endemic steady state. In spite of this we show that in a nonlinear transmission model, we have a function depending on the infectives and satisfying certain biological conditions, and leading to a sub-critical endemic equilibriums.

This dissertation addresses the causes of and policy responses to the 1990s current account crises. The first chapter explores the relative importance of external shocks as key determinants of the significant increase of foreign reserves accumulated in many emerging market economies, and provides a comprehensive framework to assess the adequacy of reserve holdings. Using the case of Mexico, I find that more than two thirds of the increase in international reserves can be replicated by a linear combination of external shocks, without an abrupt regime shift after the Tequila crisis. I also find that Mexico has historically adopted an appropriate reserves policy, with 1994 being an exception. However, under the current reserves policy, there is a positive probability of a current account crisis in the near future. In chapter Two, I investigate the optimal reserves policy. The analysis predicts an optimal level of reserves in Mexico that is considerably higher than the actual level. When I account for the possibility of a bailout by the outside world in case of a crisis, Mexico's current reserves policy is in the range of my model's predictions. The final chapter proposes a new explanation for the existence and nature of sudden stops. In my model, a sudden stop forms a necessary solution to the moral hazard problem in investment and can be rationalized as part of an optimal lending strategy in the face of asymmetric information. / Thesis (Ph.D, Economics) -- Queen's University, 2009-08-13 22:52:26.219