Study purpose. Running speed is an ability soccer players need to build attack and defence. There needs to be more research in football that applies sleds using specific loads to improve the running ...ability of college student soccer players. This study aims to analyze the effect of sled training with a load of 10 kilograms on the running speed of college student soccer players.
Materials and methods. This study uses a quantitative approach with a quasi-experimental design research type, with the research design used being a one-group pretest-posttest design. The sample used in this research was 14 students taken from a population of 95 individuals using random sampling techniques. The study sample used had characteristics of age 18 ± 0.75 years, height 169.42 ± 5.84 cm, weight 58.5 ± 4.21 kg, and BMI 20.44 ± 2.00. Treatment was carried out for six weeks with a frequency of three times a week. The 20-meter sprint speed test was used as an instrument for collecting speed data. The data analysis technique uses a paired samples t-test at a significance level (α) 0.05. The prerequisite test used is the Shapiro-Wilk test.
Results. The research showed increased players’ running speed obtained from the pretest results of 4.48 ± 0.291 and the post-test results of 4.15 ± 0.266 from the 20-meter sprint test.
Conclusions. Based on the results of the paired sample t-test, it can be concluded that there is a significant increase in the running speed of college student soccer players using 10 kg sleds.
The material used for the rocket sleds in this study was 30CrMnSiNi2A. The research focused on examining the wear patterns and elemental distribution of the 30CrMnSiNi2A alloy under high-speed ...(34.56 m/s, 69.12 m/s, 101 m/s) and heavy-load (150–600 N) conditions through both experimental and simulation methods. A conceptual wear model was developed by integrating experimental results with numerical outcomes. At speeds of 34.56 m/s and 69.12 m/s, the friction coefficient and wear rate decreased with increasing applied pressure. At 101 m/s, the friction coefficient was less influenced by pressure, whereas the wear rate increased with increasing pressure. Simulation results show that under a load of 600 N, the von Mises stress consistently increased with increasing speed.
Here are described two sleds, presumed to date to the time of the Clovis (Llano) archaeological culture or approximately 13,500-12,500 years ago, that were discovered at saline springs in New York ...state and Kentucky state. For what purpose these sleds may have been intended and why they were abandoned are addressed by referring to eastern Eurasian ethnography. The proboscidean components used in their construction may have restricted use of these sleds to ritual activities.
Dans cet article, sont décrits deux traîneaux, dont on présume qu’ils datent de l’époque de la culture Clovis (Llano), aux environs de 13500 à 12500 ans. Ces traîneaux ont été découverts au niveau de sources d’eaux salées dans les états de New York et du Kentucky. À quoi ces traîneaux ont pu être destinés et pourquoi ont-ils été abandonnés ? Ce sont les questions abordées ici, en se référant à l’ethnographie eurasienne de l’Est. Les composants proboscidiens utilisés dans leurs constructions pourraient avoir restreint l’utilisation de ces traîneaux aux activités rituelles.
•The penetration depth and hole shape of each jet element into the thick-walled moving target can be accurately calculated by theoretical model.•A disturbance criterion is proposed to judge the ...motion state of the jet element after impacting the side of the thick-walled moving target.•The paper innovatively proposes a rocket sled testing method using a precise detonation control system to achieve the interaction process of a thick-walled moving target and a shaped charge.•To improve the ability of shaped charge warhead to penetrate a high-speed moving target, the velocity and diameter of the jet tip must be increased when designing the shaped charge.
This study proposes a new rocket sled testing method using a precise detonation control system to achieve the interaction process of a thick-walled moving target and a shaped charge. The shaped charge jet's penetration into the thick-walled moving target is divided into two stages by using theoretical methods. The penetration depth and hole shape of each jet element into the moving target can be accurately calculated through a virtual source point method. A disturbance criterion is proposed to judge the motion state of the jet element after impacting the side of the thick-walled moving target. The effect of the target's moving velocity on the hole shapes and the influence of the target's strength on the penetration depth is analyzed.
Competitions involving sled dogs are rapidly growing and body temperature assessment could represent a prompt and non-invasive method of screening for potential pathological conditions during or ...after activity. The aim of this clinical study was to evaluate if thermography is able to monitor the pre- and post-competition ocular and superficial body temperature variations during a sled dog competition. It subsequently compared the data relating to the ocular temperatures in different race types: mid-distance (30 km) and sprint (≤16 km). Results showed a statistically significant increase in post-competition ocular temperature of both eyes, regardless of the length of the race. The relative increase in the temperatures of the other body surfaces was lower than the expected values, probably due to the influence of environmental and subjective factors such as the type of coat of the Siberian Husky or subcutaneous fat. Infrared thermography has therefore proved to be useful method in sled dog competition conditions for screening superficial temperature variations, as the investigation is normally conducted in an external environment and often in demanding work conditions.
The steady operation and extended service lives of rocket sled test systems are impacted by the tribological performances of the rocket sled sliders. In this work, CoCrNi and CoCrFeMnNi alloys were ...considered candidate materials for rocket sled sliders serving under high-speed and heavy-load conditions. The simulation analysis was carried out by ANSYS. The results showed that the stress on the contact surface was uneven, and there were stress gradient changed and stress concentration. Significant wear occurred on the front-end of the slider. The results of this work can serve as a reference for practical engineering applications involving rocket sled sliders.
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•The finite element method is used to analyze and solve the problem.•Computational convergence is realized by acceleration factor.•Significant wear occurred on the front-end of the slider.•CoCrNi material slider has the best wear reduction performance.
The use of dabigatran in patients with non-valvular atrial fibrillation (AF) has widely increased in the last decades, due to its positive effects in terms of safety/efficacy. However, because of the ...risk of major bleeding, a great degree of attention has been suggested in elderly patients with multiple comorbidities. Notably, dabigatran mainly undergoes renal elimination and dose adjustment is recommended in patients with Chronic Kidney Disease (CKD). In this regard, the onset of an abrupt decrease of kidney function may further affect dabigatran pharmacokinetic profile, increasing the risk of acute intoxication. Idarucizumab is the approved antagonist in the case of dabigatran-associated major bleeding or concomitant need of urgent surgery, but its clinical use is limited by the lack of data in patients with Acute Kidney Injury (AKI). Thus, the early start of Extracorporeal Kidney Replacement Therapy (EKRT) could be indicated to remove the drug and to reverse the associated excess anticoagulation. Sustained Low-Efficiency Dialysis (SLED) could represent an effective therapeutic option to reduce the dabigatran plasma levels rapidly while avoiding post-treatment rebound. We present here a case series of three AKI patients with acute dabigatran intoxication, effectively and safely resolved with a single SLED session.