496 resultados para resistance exercise


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Throughout Australia, regulation of the power of sale is highly inconsistent. In response to the uncertain nature of the mortgagee’s duty at common law, many legislatures have intervened. As a result, there has been a proliferation of statutory formula conferring varying degrees of protection on mortgagors. The differences in approach indicate a lack of consensus as to the best method of regulation. This article exposes the extent of the inconsistency and provides a comparative assessment of the various provisions with reference to the policy concerns that underpin legislative intervention. The article identifies a number of deficiencies associated with existing provisions and concludes that mortgagees and mortgagors alike would benefit from improved clarity and consistency. To that end, the article proposes a model provision that seeks to address the deficiencies identified.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

With ever-increasing share of power electronic loads constant power instability is becoming a significant issue in microgrids, especially when they operate in the islanding mode. Transient conditions like resistive load-shedding or sudden increase of constant power loads (CPL) might destabilize the whole system. Modeling and stability analysis of AC microgrids with CPLs have already been discussed in literature. However, no effective solutions are provided to stabilize this kind of system. Therefore, this paper proposes a virtual resistance based active damping method to eliminate constant power instability in AC microgrids. Advantages and limitations of the proposed method are also discussed in detail. Simulation results are presented to validate the proposed active damping solution.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Introduction Intense exercise induced acidosis occurs from the accumulation of hydrogen ions as by-products of anaerobic metabolism. Oral ingestion of ß-alanine, a limiting precursor of the intracellular physiochemical buffer carnosine in skeletal muscle, may counteract any detrimental effect of acidosis and benefit performance. The aim of this study was to investigate the effect of ß-alanine as an ergogenic aid during high intensity exercise performance in healthy males. Methods Five males ingested either ß-alanine (BAl) (4.8 g.d-1 for 4wk, then 6.4 g.d-1 for 2wk) or placebo (Pl) (CaCO3) in a crossover design with 6 wk washout between. Following supplementation, participants performed two different intense exercise protocols over consecutive days. On the first day a repeated sprint ability (RSA) test of 5 x 6s, with 24s rest periods, was performed. On the second day a cycling capacity test measuring the time to exhaustion (TTE) was performed at 110% of their max workload achieved in a pre supplementation max test (CCT110%). Non-invasive quantification of carnosine, prior to, and following each supplementation, with magnetic resonance spectrometry was performed in the soleus and gastrocnemius. Time to fatigue (CCT110%), peak and mean power (RSA), blood pH, and plasma lactate were measured. Results Muscle carnosine concentration was not different prior to ß-alanine supplementation and increased 18% in the soleus and 26% in the gastrocnemius, respectively with 6 wk supplementation. There was no difference in the measured performance variables during the RSA test (peak and average power output). TTE during the CCT110% was significantly enhanced following the ingestion of BAl (155s ± 19.03) compared to Pl (134s ± 26.16). No changes were observed in blood pH during either exercise protocol and during the recovery from exercise. Plasma lactate in the BAl condition was significantly higher than Pl only from the 15th minute following exercise during the CCT110%. FIG. 1: Changes in carnosine concentration in the gastrocnemius prior and post 6 week chronic supplementation of placebo and β-alanine. Values expressed as mean.* p<0.05 from Pl at 6 weeks, # p<0.05 from pre supplementation. Conclusion/Discussion Greater muscle carnosine content following 6wk supplementation of ß-alanine enhanced the potential for intracellular buffering capacity. However, this only translated into enhanced performance during the CCT110% high intensity cycling exercise protocol, with no change observed during the RSA test. No differences in post exercise and recovery plasma lactates and blood pH, indicates that 6wks ß-alanine supplementation has no effect on anaerobic metabolism during multiple bout high intensity exercise. Changes in plasma lactate during recovery supports that ß-alanine supplementation may affect anaerobic metabolism however during single bout high intensity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Intense exercise induced acidosis occurs after accumulation of hydrogen ions as by-products of anaerobic metabolism. Oral ingestion of ß-alanine, a limiting precursor of the intracellular physiochemical buffer carnosine in skeletal muscle, may counteract detrimental effects of acidosis and benefit performance. This study aimed to investigate the effect of ß-alanine as an ergogenic aid during high intensity exercise performance. Five healthy males ingested either ß-alanine or placebo (Pl) (CaCO3) in a crossover design with 6 wk washout between. Participants performed two different intense exercise protocols over consecutive days. On the first day a repeated sprint ability (RSA) test was performed. On the second day a cycling capacity test measuring the time to exhaustion (TTE) was performed at 110% of maximum workload achieved in a pre supplementation max test (CCT110%). Non-invasive quantification of carnosine, prior to, and following each supplementation, with in vivo magnetic resonance spectrometry was performed in the soleus and gastrocnemius muscle. Time to fatigue (CCT110%), peak and mean power (RSA), blood pH, and plasma lactate were measured. Muscle carnosine concentration was not different prior to ß-alanine supplementation and increased 18% in the soleus and 26% in the gastrocnemius, respectively after supplementation. There was no difference in the measured performance variables during the RSA test (peak and average power output). TTE during the CCT110% was significantly enhanced following the ingestion of BAl (155s ± 19.03) compared to Pl (134s ± 26.16). No changes were observed in blood pH during either exercise protocol and during the recovery from exercise. Plasma lactate after BAI was significantly higher than Pl only from the 15th minute following exercise during the CCT110%. Greater muscle carnosine content following 6wk supplementation of ß-alanine enhanced the potential for intracellular buffering capacity. This translated into enhanced performance during the CCT110% high intensity cycling exercise protocol but not during the RSA test. The lack of change in plasma lactate or blood pH indicates that 6wks ß-alanine supplementation has no effect on anaerobic metabolism during multiple-bout high-intensity exercise. Changes measured in plasma lactate during recovery support the hypothesis that ß-alanine supplementation may affect anaerobic metabolism particularly during single bout high intensity.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Artemisinin (ART) based combination therapy (ACT) is used as the first line treatment of uncomplicated falciparum malaria in over 100 countries and is the cornerstone of malaria control and elimination programs in these areas. However, despite the high potency and rapid parasite killing action of ART derivatives there is a high rate of recrudescence associated with ART monotherapy and recrudescence is not uncommon even when ACT is used. Compounding this problem are reports that some parasites in Cambodia, a known foci of drug resistance, have decreased in vivo sensitivity to ART. This raises serious concerns for the development of ART resistance in the field even though no major phenotypic and genotypic changes have yet been identified in these parasites. In this article we review available data on the characteristics of ART, its effects on Plasmodium falciparum parasites and present a hypothesis to explain the high rate of recrudescence associated with this potent class of drugs and the current enigma surrounding ART resistance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Amplification of the Plasmodium falciparum multidrug resistance 1 gene (pfmdr1) has been implicated in multidrug resistance, including in vitro resistance to artelinic acid (AL). The stability and fitness of having multiple copies of pfmdr1 are important factors due to their potential effects on the resistance phenotype of parasites. These factors were investigated by using an AL-resistant line of P. falciparum (W2AL80) and clones originating from W2AL80. A rapid reduction in pfmdr1 copy number (CN) was observed in the uncloned W2AL80 line; 63% of this population reverted to a CN of <3 without exposure to the drug. Deamplification of the pfmdr1 amplicon was then determined in three clones, each initially containing three copies of pfmdr1. Interestingly, two outcomes were observed during 3 months without drug pressure. In one clone, parasites with fewer than 3 copies of pfmdr1 emerged rapidly. In two other clones, the reversion was significantly delayed. In all subclones, the reduction in pfmdr1 CN involved the deamplification of the entire amplicon (19 genes). Importantly, deamplification of the pfmdr1 amplicon resulted in partial reversal of resistance to AL and increased susceptibility to mefloquine. These results demonstrate that multiple copies of the pfmdr1-containing amplicon in AL-resistant parasites are unstable when drug pressure is withdrawn and have practical implications for the maintenance and spread of parasites resistant to artemisinin derivatives.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Chloroquine-resistant Plasmodium falciparum was highly prevalent in Hainan, China, in the 1970s. Twenty-five years after cessation of chloroquine therapy, the prevalence of P. falciparum wild-type Pfcrt alleles has risen to 36% (95% confidence interval, 22.1 to 52.4%). The diverse origins of wild-type alleles indicate that there was no genetic bottleneck caused by high chloroquine resistance.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Bulk heterojunction organic solar cells based on poly[4,7-bis(3- dodecylthiophene-2-yl) benzothiadiazole-co-benzothiadiazole] and [6,6]-phenyl C71-butyric acid methyl ester are investigated. A prominent kink is observed in the fourth quadrant of the current density-voltage (J-V) response. Annealing the active layer prior to cathode deposition eliminates the kink. The kink is attributed to an extraction barrier. The J-V response in these devices is well described by a power law. This behavior is attributed to an imbalance in charge carrier mobility. An expected photocurrent for the device displaying a kink in the J-V response is determined by fitting to a power law. The difference between the expected and measured photocurrent allows for the determination of a voltage drop within the device. Under simulated 1 sun irradiance, the peak voltage drop and contact resistance at short circuit are 0.14 V and 90 Ω, respectively. © 2012 American Institute of Physics.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

With an ever changing landscape including National Registration, endorsed areas of practice, establishment of Sport and Exercise Psychology coordinators within National Sporting Organisations, changes to the National and State Sporting Insitutions, this forum looks to explore through collegiate discussion the impacts, current and future implications for our profession across training, supervision, research and applied practice in Australia.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose Prior research emphasizes that organizational founders have a good deal of influence in organizational development and, where ICTs are involved, a generic strategy is usually deployed by managers in order to deal with any resistance that might occur. Cognisant of this, we investigated the role played by a Managing Director of an SME consultancy in an ICT project associated with organizational development. Design/methodology/approach This study is based on an ethnography of a ICT related change management initiative which, theoretically, takes into account though from the social shaping of technology – speifically the idea that technologies in their broadest sense are subject to ongoing work beyond the design stage. Findings We argue that Markus’ Interaction Theory of resistance still has relevance today and we extend it by emphasizing the problem of homogenizing users and downplaying their ability to appropriate resistance strategies in situ. Research limitations/implications Our study is based upon one group of individual’s experiences. Further case studies of resistance success are required which further highlight how such this is achieved and why. Practical implications Those engaged with organisational development projects need to be better educated as to the reasons for resistance, particularly positive ones, and the methods by which this might take place. Originality/value This study conceptualises strategies for ‘overcoming’ resistance as managerial technologies. Conceptualising them in this way, shows the deployement of such technologies to be a complicated and active process where the audience for such things are involved in how they are received and appropriated to suite differing agendas.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Road asset managers are seeking analysis of the whole road network to supplement statistical analyses of small subsets of homogeneous roadway. This study outlines the use of data mining capable of analyzing the wide range of situations found on the network, with a focus on the role of skid resistance in the cause of crashes. Results from the analyses show that on non-crash-prone roads with low crash rates, skid resistance contributes only in a minor way, whereas on high-crash roadways, skid resistance often contributes significantly in the calculation of the crash rate. The results provide evidence supporting a causal relationship between skid resistance and crashes and highlight the importance of the role of skid resistance in decision making in road asset management.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Recently, Boots & Begon (1993) described the development of resistance to granulosis virus (GV) (Baculoviridae) infection in the moth Plodia interpunctella, following prolonged exposure to virus in laboratory cultures. Resistant insects exhibited reduced fitness in other respects, namely slower development and reduced egg viability, compared to control insects. These results were interpreted as pleiotropic effects of selection at the loci controlling resistance. Similar results have been described in a previous study: Fuxa & Richter (1989) used artificial selection to increase resistance to nuclear polyhedrasis virus (NPV) (Baculoviridae) infection in the moth Spodoptera frugiperda. The resulting gain in resistance they interpreted as the result of an increase in the frequency of alleles conferring resistance. Again, resistant insects exhibited maladaptive traits compared to controls, including a shorter adult life span, reduced number of eggs and reduced egg viability. In both studies the suggestion is made that selection against maladaptive traits will result in a decline in resistance, once selection for resistance is removed. Boots & Begon (1993) described a decrease in development time (towards that of control insects) within two generations of removing selection for resistance. Fuxa & Richter (1989) describe a decrease in resistance, so that within two generations of relaxing selection, previously resistant lines were not significantly more resistant than control insects. . .

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective Exercise has the potential to offer a range of health benefits in addition to improving healing outcomes for people with venous leg ulcers. However despite evidence based recommendations, most of these individuals do not engage in regular exercise. The aim of this study was to gain an understanding of the perspectives of adults with venous leg ulcers, in relation to exercise. Method This was a qualitative design using semi-structured interviews and discussions. Ten participants with venous leg ulceration volunteered to participate. Recruitment was through a specialist wound clinic. Verbatim data were collected by an experienced moderator using a semi-structured guide. Data saturation was reached after three group discussions and two interviews. A random selection of transcripts was sent back to the participants for verification. Thematic content analysis was used to determine major themes and categories. Two transcripts were independently analysed, categories and themes independently developed, cross checked and found comparable. Remaining transcripts were analysed using developed categories and codes. Results Regardless of their current exercise routine, participants reported exercising prior to venous leg ulceration and expressed an interest in either becoming active or maintaining an active lifestyle. Overall four themes emerged from the findings: i) participant understanding of the relationship between chronic venous insufficiency and exercise patterns, ii) fear of harm impacts upon positive beliefs and attitudes to exercise, iii) perceived factors limit exercise and iv) structured management facilitates exercise. Conclusion The value of exercise in improving outcomes in venous leg ulcers lies in its capacity to promote venous return and reduce the risk of secondary conditions in this population. Despite motivation and interest in being exercise active, people with venous leg ulcers report many obstacles. Further exploration of mechanisms that assist this patient population and promote understanding about management of barriers, coupled with promotion of enabling factors is vital for improving their exercise participation.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

ABL inhibitors have revolutionized the clinical management of chronic myeloid leukemia, but the BCR-ABLT315I mutation confers resistance to currently approved drugs. Chan et al. show, in this issue of Cancer Cell, that " switch-control" inhibitors block BCR-ABLT315I activity by preventing ABL from switching from the inactive to active conformation.