191 research outputs found
Adaptations to Post-exercise Cold Water Immersion: Friend, Foe, or Futile?
In the last decade, cold water immersion (CWI) has emerged as one of the most popular post-exercise recovery strategies utilized amongst athletes during training and competition. Following earlier research on the effects of CWI on the recovery
of exercise performance and associated mechanisms, the recent focus has been on how CWI might influence adaptations to exercise. This line of enquiry stems from classical work demonstrating improved endurance and mitochondrial development in
rodents exposed to repeated cold exposures. Moreover, there was strong rationale that CWI might enhance adaptations to exercise, given the discovery, and central role of peroxisome proliferator-activated receptor gamma coactivator-1a (PGC-1a) in
both cold- and exercise-induced oxidative adaptations. Research on adaptations to post-exercise CWI have generally indicated a mode-dependant effect, where resistance training adaptations were diminished, whilst aerobic exercise performance seems unaffected but demonstrates premise for enhancement. However, the general suitability of CWI as a recovery modality has been the focus of considerable debate, primarily given the dampening effect on hypertrophy gains. In this mini-review, we highlight the key mechanisms surrounding CWI and endurance exercise adaptations, reiterating the
potential for CWI to enhance endurance performance, with support from classical and contemporary works. This review also discusses the implications and insights (with regards to endurance and strength adaptations) gathered from recent studies examining the longer-term effects of CWI on training performance and recovery. Lastly, a periodized approach to recovery is proposed, where the use of CWI may be incorporated during competition or intensified training, whilst strategically avoiding periods following training focused on improving muscle strength or hypertrophy
Editorial: The use of post-exercise cooling as a recovery strategy: Unraveling the controversies
Post-exercise cooling is a popular recovery strategy utilized by athletes, and of interest to many research groups. Significant body of research have examined the effects of post-exercise cooling on outcomes such as physical performance, regulation of inflammatory biomarkers, and psychophysical indices related to perceived fatigue, recovery and wellbeing. ..
PGC-1α mediated muscle aerobic adaptations to exercise, heat and cold exposure
PGC-1α is regarded as a key regulator of mitochondrial biogenesis due to its central role in regulating the activity of key transcription factors associated with encoding mitochondrial components. Additionally, PGC-1α has shown to mediate adaptations that increase fat metabolism and angiogenesis, contributing to the overall oxidative phenotype of the muscle. While it is well established that exercise is a potent stimulator of PGC-1α, recent evidence indicates that heat and cold exposures may also influence mitochondrial biogenesis through the up-regulation of PGC-1α. This highlights the potential use of these modalities in conjunction with exercise to enhance training adaptations. As such, the purpose of this review is to describe the possible mechanisms and pathways by which exercise, as well as hot and cold exposures may influence mitochondrial biogenesis. It is clear that changes in intracellular calcium, oxidative stress and phosphorylation potential are major up-regulators of PGC-1α during exercise. Moreover, there is evidence implicating calcium signalling, in addition to β-adrenergic activation in cold-induced mitochondrial biogenesis, while PGC-1α during heat exposure is likely triggered by changes in phosphorylation potential and nitric oxide signalling. However, these mechanisms appear to change considerably when cold/heat is administered following exercise, and seem to be dependent on the experimental models used (i.e. in vitrovs. in vivo, rodent vs. human). Understanding the effects heat/cold exposure and its interaction with exercise may lead to the optimisation and development of temperature-related interventions to enhance training adaptations, or aid in the treatment of mitochondrial related diseases
Influence of cupping treatment on high-intensity anaerobic performance
The use of cupping therapy prior to sports events has increased in popularity, with limited evidence to support its efficacy. The purpose of this study was to evaluate the efficacy of dry and wet cupping therapy on subsequent Wingate anaerobic test (WAnT) performance. Twelve trained men participated in this repeated measures randomized crossover study (age 24.9 ± 4.8 years; body mass index 27.6 ± 14.3 kg.m-2). Participants were familiarized with the ergometer and the Wingate anaerobic test on three separate occasions. They then randomly performed three experimental Wingate tests separated by 48-72 h after either dry cupping (DRY), wet cupping (WET), or no treatment (CON). Repeated measures ANOVA and Pearson’s correlation coefficient were used to analyze data and determine the relationships between WAnT and peak lactate and heart rate (HR). Peak power (PP), mean power (MP), and fatigue index (FI) were similar in all treatments (p=.47-.72). Heart rate (HR) and lactate increased similarly at all time points in all treatments (p<.001 for all comparisons). Post-WAnT peak HR was moderately negatively correlated with PP in all treatments and MP in CON only (p<.05 for all correlations). No other significant correlations were detected. The present findings demonstrate no beneficial effects of wet and dry cupping therapy, and hence do not support its use prior to high-intensity anaerobic sports events
An Investigating of the Impact of Bed Flume Discordance on the Weir-Gate Hydraulic Structure
Discordance and concordance play a significant role in the hydraulic response for the flume, open channel, hydraulic structure, and flow field measurement. Bed discordance and bed concordance are regarded as common problems in open channels. Discordance is the dominant one, which could have an effect on the hydraulic structure that is constructed inside the channel. This paper deals with the impact of bed flume discordance on hydraulic flow characteristics at the weir-gate downstream hydraulic regime. Four configurations with different lengths and heights of the bed flume discordance are adopted here to investigate the impact of these configurations on the hydraulic characteristics. In addition, one configuration of the bed flume concordance is adopted to compare with the other four configurations. At downstream, the average water depth becomes dimensionless by dividing by upstream water depth, vertical distance between weir and gate, length of downstream, length of concordance, and length of discordance in order to evaluate the inequality in the distribution of Froude number. On one hand, certain results appear strongly between Reynolds number and Froude number at downstream, actual discharge and flow velocity at downstream, flow area past the gate and Froude number at downstream. On the other hand, there was a complex dramatic relation between the weir-gate discharge coefficient and Froude number at downstream. Overall, the study shows that there is a good relationship between specific energy, water depth, and flow speed. Doi: 10.28991/HIJ-2022-03-03-09 Full Text: PD
Efeito sinérgico da oxitetraciclina em um tratamento combinado com Carboplatina na linhagem de células cancerígenas pulmonares MCF-7
In breast cancer treatment, chemotherapy resistance is a major problem where many receptive tumors rebound and develop resistance. When provided in combination, cancer drugs are most successful, thus reducing the risk of developing resistant cancer cells. However, the evaluation of combination therapies has increased rapidly in recent years. Consequently, by repurposing old treatments, the discovery of additional medicines that may interact synergistically with chemotherapy is considered a current medical aim through discovering a new cancer medication or therapeutic strategy. The purpose of this research is to increase the anti-cancer activity of carboplatin (CP) by increasing the apoptotic effect of breast cancer cells (MCF-7) during in vitro experiments in combination with oxytetracycline. Our results showed a high synergistic effect between oxytetracycline and carboplatin, MCF-7 representative cell treated with carboplatin with/without different concentrations of oxytetracycline (5% and 10% of IC50). Oxytetracycline, which potentiated the action of carboplatin and/or had notable activity was reported as a single agent. This research demonstrated the synergistic relationship between oxytetracycline and carboplatin in viability assays. Surprisingly, our findings suggest that inhibiting treatment strategies can extend carboplatin’s therapeutic window, potentially allowing for cancer therapy.No tratamento do câncer de pulmão a resistência à quimioterapia é o maior problema no qual muitos tumores receptivos apresentam um rebote e desenvolvem a resistência. Quando oferecidas em combinações, as drogas anticancerígenas apresentam maior taxa de sucesso, reduzindo assim o risco de desenvolvimento de células cancerígenas resistentes. Contudo, a avaliação das terapias de combinação tem crescido muito rapidamente. Consequentemente, por reaproveitamento de tratamentos antigos, a descoberta de novos medicamentos adicionais que podem interagir sinergicamente com a quimioterapia que é considerada como auxílio médico na corrente busca à descoberta de novas medicações anticancerígenas ou estratégias terapêuticas. O propósito da presente pesquisa é aumentar a atividade anticancerígena da Carboplatina (CP) pelo incremento do efeito apoptótico de células de câncer pulmonar (MCF-7) em experimentos in vitro pela combinação com oxitetraciclina. Os resultados obtidos confirmaram elevado efeito sinérgico entre oxitetraciclina e Carboplatina em células MCF-7 representativas tratadas com Carboplatina, com e sem diferentes concentrações de oxitetraciclina (5% e 10% de IC50). A oxitetracilina que potencializou a ação da Carboplatina e/ou teve uma notável atividade relatada como um agente isolado. A pesquisa demonstrou a relação sinérgica entre oxitetraxiclina e Carboplatina nos ensaios de viabilidade. Surpreendentemente, os resultados obtidos sugeriram que as estratégias de tratamento inibidor podem aplicar uma janela terapêutica da Carboplatina com potencial para a terapia do câncer
Comparison Study of Environmental Impacts between Mid (CML) and End Point (Eco 95) Methods for Babel Lead Acid Battery Production Processes
In this research, quantitative analysis, comparison of the environmental impacts for Iraqi Babel Lead acid battery (capacity of 135 Amps/hr) throughout the production processes is conducted for 2012 year, according to the ISO (14040-14043) series of standards. Two impact assessment methods employed are; Centre of Environmental Studies (CML–midpoint) and (Eco 95-endpoint). Chain Management Life Cycle Analysis [CMLCA] software is used to process and generate the collected data. In CML (mid-point) method four potential environmental impact categories are; [Global Warming Potential (GWP), Acidification, Eutrophication, and Human toxicity], while Eco 95 (endpoint) method evaluates six categories of environmental impact are; [Global Warming Potential (GWP), Acidification, Eutrophication, Heavy metals, Summer, and Winter Smog]. Results generated according to CML method reveal that formation process as the highest contributor to GWP by (26%), Eco 95 declared contribution to the GWP of the same process by (4%). Through CML (mid-point) the assembly process is identified as having the most significant impact on acidification by (50%), while Eco 95 method quantify acidification for the same process by (4%). Human toxicity is allocated by (60%) contribution in the assembly process by CML method, whereas the same process is identified as the most hazardous process of (93%) contribution heavy metals impact is, and winter smog (3%) according to Eco 95 method. Formation process is the highest contributor to Eutrophication according CML method, while Eutiphication is not of concern, according to (Eco 95) for this process. It is concluded that the environmental impacts of Babel battery spread over the production processes and every process have certain environmental impact category (nerveless the quantifying method). Therefore, it is recommended using both methods to expose all the environmental categories, and to control the environmental aspects of the company, also it is recommended to use new technologies for battery production that have less impact on the environment
Estimation of Testosterone, Estradiol and some Markers in Sera of Iraqi Patients with Benign Prostatic Hyperplasia.
Benign prostatic hyperplasia (BPH) is one of the most common disease and major cause of morbidity in elderly men which may lead to bladder outflow obstruction and lower urinary tract symptoms (LUTS). Although sex steroid hormones play fundamental roles in prostate growth, their clinical significance is not completely clear. In the present study we assessed whether serum hormones levels as markers of prostate disease. This study includes (40) patients with benign prostatic hypertrophy and (40) control group with age rang (41-79) and (42-71) years respectively. The following biochemical investigations have been studied: Testosterone, Estradiol (E2), and Prostatic Specific Antigen (PSA) levels using ELISA method which correlated with the disease. Also body mass index (BMI), the prostate size by digital rectal examination (DRE), flow rate, and American Urology Association Symptoms Index (AUASI), of the patients which correlate hormones levels with age. The testosterone concentrations were significantly lower in patients with BPH than control group (p?0.05), while the Estradiol and PSA concentrations were significantly higher in patients with BPH than control group (p?0.05). The net result is a significant decrease in the T/E2 ratio allowing the imbalance between androgens and estrogen regulation of prostate growth to shift towards estrogen dominance. It has been proposed that increased estrogenic stimulation of the prostate in the aging male may lead to reactivation of growth and subsequent hyperplasia transformatio
LATEST TOURNAISIAN (EARLY CARBONIFEROUS) CONODONTS FROM THE TABAI LIMESTONE, TIRAH, NORTHWESTERN PAKISTAN
A new stratigraphic unit, the Tabai Limestone of the poorly known Tirah area of northwest Pakistan, is one of several Early Carboniferous carbonate units distributed along the North Gondwana margin, some connected with transgressive interludes. The Tabai Limestone has produced latest Tournaisian (Early Carboniferous) conodonts indicative of the middle of the anchoralis-latus Zone
Experimental Study of 3D printing Density Effect on the Mechanical Properties of the Carbon-Fiber and Polylactic Acid Specimens
Two 3D printed materials (Polylactic Acid and Carbon fiber) with variable printing density have been investigated due to their practical uses in the engineering utilization. The effect of printing density composites was studied by the tensile test. The used materials stress-strain curves were analyzed to find modulus of elasticity and ultimate tensile strength of the mentioned materials. The results manifested that the carbon fiber has the highest strength-weight ratio. On the other hand, the carbon fiber showed more ductility than the Polylactic Acid. The results of this paper will be aiding the researchers or engineering students to decide which material is suitable for 3D printing applications
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