There are some features for an approved soccer ball by Fédération Internationale de Football Association (FIFA), such as properties of the material, mass, pressure, stitches, etc. Many of these features up to now have been studied; nevertheless, the mechanical properties of the soccer balls to date have not been well reported. The chief purposes of the current research, hence, were to calculate the mechanical properties of the soccer balls, i.e., linear elastic, nonlinear hyperelastic, and viscoelastic, at two different sizes, including 4 and 5 which are using for football and futsal, respectively. To do this, compressive and stress-relaxation loading were applied to 38 approved soccer balls to quantify the stress–strain as well as reduced relaxation function of the balls. The strain/displacement of the balls was also measured via a high-speed camera using Digital Image Correlation (DIC) technique. The results revealed the mean elastic modulus of 66 and 67 kPa for the football and futsal balls, respectively. In addition, the maximum stresses of the football and futsal balls were 16 and 13 kPa, respectively. The nonlinear mechanical response of the soccer balls were analyzed using hyperelastic material models, i.e., Mooney-Rivlin and Ogden. A Finite Element (FE) model was also developed to verify the hyperelastic data compared to the experimental ones and, remarkably, the numerical data were in consistence with the experimental data. Finally, Prony- series was employed to quantify the viscoelastic properties of the balls. During the game, a soccer ball can reach to a speed of 210 km/h that can damage the human eye; however, the injury detail still has not been studied. 相似文献
Objective Albuminuria is an early marker of renal impairment and a powerful factor of progression of renal disease in type 2 diabetes (T2D). Approximately, one-third of patients with T2D have micro- or macroalbuminuria and these patients have a high risk of progression toward End Stage Renal Disease (ESRD) as well as increased cardiovascular disease. The aim of this study was to determine the prevalence of remission, regression, persistence, and progression of albuminuria, and to evaluate the impact of change in albuminuria on kidney disease and cardiovascular disease in a prospective cohort of patients with T2D. Methods This is a prospective study. The Ethics Committee of Morocco’s Mohammed V University in Rabat approved the study protocol. Inclusion criteria targeted patients who were type 2 diabetics with albuminuria?>30?mg/day, and who had been regularly followed-up in nephrology consultation for at least 36 months. Results Five-hundred twenty-four patients were included. 75.8 and 24.6% of all patients had micro- and macroalbuminuria at enrollment in the study. At the end of the study, 91, 141, 199, and 93 patients had remission, regression, persistence, and progression of albuminuria, respectively. Remission of microalbuminuria to normoalbuminuria was observed in 23.6% of cases. Regression of macroalbuminuria to micro- was observed in 29.9% of cases. Conclusion In our study, the incidence of remission and/or regression of micro- and macroalbuminuria was higher. The incidence of ESRD and the occurrence of cardiac events were greater in the regression, persistence, and progression groups than in the remission of albuminuria group. 相似文献
Mercury (Hg), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) concentrations differ across seafood types. Our aim was to investigate the association of Hg, EPA, and DHA, as well as avid consumption of diverse seafood types, with cardiovascular variables heart rate variability (HRV) and QT interval duration (QTc) in a contemporary population. We measured HRV and QTc by Holter monitor, EPA and DHA in plasma, total Hg in whole blood, and possible confounders in 94 avid seafood consumers from Long Island, NY. Participants had mean Hg of 8.4 mcg/L, mean EPA of 1.2%, and mean DHA of 3.7% of total fatty acids. Adjusted for possible confounders, EPA+DHA, Hg, and total seafood consumption were not associated with HRV or QTc. Associations with consumption of specific seafood types were suggested (eg, tuna steak with QTc and anchovies with HRV) but require verification. 相似文献
Introduction: Despite the significant advances in the pharmacological and interventional management of patients with cardiovascular disease (CVD) over the last decades, cardiovascular mortality remains the leading cause of death. Large randomized clinical trials have investigated the efficacy and safety of different antithrombotic medications in patients with CVD. Although female gender is generally underrepresented in these clinical trials, most analyses clearly indicate that both men and women may accrue therapeutic benefits from antithrombotic management strategies.
Areas covered: This review aims to provide a comprehensive and focused update on gender-related comparative clinical studies of antithrombotic therapies in patients suffering from CVD.
Expert opinion: Current evidence supports the understanding of a similar therapeutic effect between genders with signals of an increased risk of bleeding in women. However, important gaps in evidence exist due to the overall limited percentage of women that have been enrolled in randomized controlled trials. A greater awareness of gender-related issues in antithrombotic therapy should be promoted among physicians and further evidence from large clinical trials looking at the safety and efficacy balance of different antithrombotic strategies in women is warranted. 相似文献
Surgical extraction of third molars is one of the most common of all surgical procedures. The outcome of third molar surgery includes pain, trismus, edema, nausea, infection, and alveolar osteitis. The intent of this article is to provide a literature review and analysis of the various chemotherapeutic agents used to control, minimize, or eliminate these outcomes. Unfortunately, comparison of the published studies represents a tremendous challenge because of the variability in parameters and methods used for each study. A trend does exist among many of the current researchers, who realize that randomized, controlled, evidence-based research rather than personal experience is necessary to develop appropriate guidelines for using chemotherapeutic agents. 相似文献
The unclear bio-safety issue and potential risk of nanoparticles (NPs) on various organelles can be considered as a major challenge. In the present study, we have assessed the green synthesis of ZnO nanoparticles using Hyssop (Hyssopus officinalis) extract and their effects on PC3 cell line and BALB/c mice model. The cytotoxicity of the ZnO-NPs was assessed on PC3 cell line by MTT test after characterisation. Apoptotic effect of ZnO-NPs was determined by in vitro AO/PI staining. The histopathological assessments and determination of LH and FSH levels carried out as in vivo analysis in BALB/c adult male mice. The expression of major genes involved in spermatogenesis and sperm maturation (Adam3, Prm1, Spata19, Tnp2, Gpx5) were also analysed. The obtained result demonstrated that the IC50 for PC3 cell line treated with green-synthesised ZnO-NPs during 24 and 48 hr was reported 8.07 and 5 µg/ml respectively. Meanwhile, the induced apoptosis was recorded 26.6% ± 0.05, 44% ± 0.12 and 80% ± 0.07 of PC3 cells. The results of gene expression analysis revealed that the increase in the concentration of ZnO-NPs significantly (p < .05) down-regulated the Adam3, Prm1, Spata-19, Tnp2 and Gpx5 genes. The overall results of this research elucidated that ZnO-NPs impaired spermatogenesis, sperm maturation process and sperm motility. 相似文献