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1.
Artificial surfaces are now an established alternative to grass (natural) surfaces in rugby union. Little is known, however, about their potential to reduce injury. This study characterises the spinal kinematics of rugby union hookers during scrummaging on third-generation synthetic (3G) and natural pitches. The spine was sectioned into five segments, with inertial sensors providing three-dimensional kinematic data sampled at 40 Hz/sensor. Twenty-two adult, male community club and university-level hookers were recruited. An equal number were analysed whilst scrummaging on natural or synthetic turf. Players scrummaging on synthetic turf demonstrated less angular velocity in the lower thoracic spine for right and left lateral bending and right rotation. The general reduction in the range of motion and velocities, extrapolated over a prolonged playing career, may mean that the synthetic turf could result in fewer degenerative injuries. It should be noted, however, that this conclusion considers only the scrummaging scenario.  相似文献   
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Guggulsterone, a mixture of cis (E) and trans (Z) isomers (7∶3 w/w) was synthesized from 16-DPA. The isomers were separated by column chromatography and evaluated for cardioprotective and antioxidant activities. Myocardial necrosis induced by isoproterenol in rats caused marked increase in serum creatine phosphokinase and glutamate pyruvate transaminase. Simultaneously in ischemic heart, phospholipase, xanthine oxidase and lipid peroxides were enhanced following depletion of glycogen, phospholipids and cholesterol. Treatment with guggulsterone and its both isomers at the dose of 50 mg/kg po., significantly protected cardiac damage as assessed by the reversal of blood and heart biochemical parameters in ischemic rats. The cardioprotective activity of guggulsterone and of both the isomers were compared with that of gemfibrozil at the same doses. Guggulsterone and both the isomers at tested concentrations (5–20mM) inhibited oxidative degradation of lipids in human low-density lipoprotein and rat liver microsomes induced by metal ionsin vitro. The drug counteracted against the generation of superoxide anions (O2) and hydroxyl radicals (OH) in non-enzymic test systems. It is suggested that cardioprotective and antioxidant activities of synthetic guggulsterone and guggulsterone obtained from gum resinCommiphora mukul that contains isomers E & Z in the ratio of 46∶54w/w are the same.  相似文献   
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While the debate rages on the role of social media technologies in the initial days of the Egyptian revolution of 2011, a more relevant research question today is the role of social media within an increasingly contested and turbulent political sphere. This article identifies three key modes by which social media is being exploited to impact political power, and uncovers the salience of each of these through 2 years of multisited ethnographies and interviews. First, I argue that political actors across the political spectrum, from liberals to Muslim Brotherhood (Ikhwan), are using technologies to build wider ranging, heterogeneous, and diverse networks of supporters, expanding their base from a more historically homogeneous core support group. Second, I argue that actors are working to build bridges between older and newer media platforms, recognizing that each platform is increasingly being shaped by the other. Finally, I describe some of the ways that technology is being used by activists to subvert their competition, promoting campaigns of misinformation and hacking at the expense of others.  相似文献   
5.
In this article, we present an experiential perspective on how a big data analytics course was designed and delivered to students at a major Midwestern university. In reference to the MSIS 2006 Model Curriculum, we designed this course as a level 2 course, with prerequisites in databases, computer programming, statistics, and data mining. Students in the class were mostly seniors or at the graduate level, and had a strong technical and quantitative background. We include details of concepts covered in the course, as well as summaries of four major sample course assignments used. Some of the concepts covered include large‐scale data collection and management using the Hadoop ecosystem, stream mining, visual analytics, and social network analytics. Besides Hadoop, the course also introduced various IBM and Teradata big data tools. We show how the course modules align with the intended learning goals and course objectives. A post‐course survey indicated that the structure and organization of the course helped students clearly and concisely assimilate the course content.  相似文献   
6.
The aim was to study the genotoxic effect of high concentration of thyroxine (T4) in vivo in peripheral blood lymphocytes (PBL) of the patients suffering from thyroid disorders. The effect was compared by performing in vitro experiments with addition of increasing concentration of T4 (0.125–1 µM) in whole blood samples from healthy donors. Cytokinesis-blocked micronuclei (CBMN) assay method was used to assess the DNA damage in the PBL. The study included 104 patients which were grouped as control (n = 49), hyperthyroid (n = 31) and hypothyroid (n = 24). A significant increase in micronuclei (MN) frequency was observed in hyperthyroid patients when compared with the hypothyroid and euthyroid group thereby suggesting increased genotoxicity in hyperthyroidism (p < 0.001). A significant increase in MN frequency was observed at T4 concentration of 0.5 µM and above when compared to lower T4 concentrations (0.125 and 0.25 µM) and basal in in vitro experiments (p = 0.000). The results indicate that the T4 in normal concentration does not exhibit the genotoxic effect, as observed in both the in vivo and in vitro experiments. The toxicity of T4 increases at and above 0.5 μM concentration in vitro. Therefore acute T4 overdose should be handled promptly and effectively so as to avoid the possible genotoxic effect of high concentration of T4 in vivo.  相似文献   
7.
Deficiency or excess of certain trace elements has been considered as risk factor for prostate cancer. This study was aimed to detect differential changes and mutual correlations of selected trace elements in prostate cancer tissue versus benign prostatic hyperplasia tissue. Zinc, copper, iron, calcium and selenium were analysed in histologically proven 15 prostate cancer tissues and 15 benign prostatic hyperplasia tissues using atomic absorption spectrophotometer. Unpaired two tailed t test/Mann–Whitney U test and Pearson correlation coefficient were used to compare the level of trace elements, elemental ratios and their interrelations. As compared to benign prostatic tissue, malignant prostatic tissue had significantly lower selenium (p = 0.038) and zinc (p = 0.043) concentrations, a lower zinc/iron ratio (p = 0.04) and positive correlation of selenium with zinc (r = 0.71, p = 0.02) and iron (r = 0.76, p = 0.009). Considerably divergent interrelationship of elements and elemental ratios in prostate cancer versus benign prostatic hyperplasia was noted. Understanding of differential elemental changes and their interdependence may be useful in defining the complex metabolic alterations in prostate carcinogenesis with potential for development of element based newer diagnostic, preventive and therapeutic strategies. Further studies may be needed to elucidate this complex relationship between trace elements and prostate carcinogenesis.  相似文献   
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Ensuring quality of laboratory services is the need of the hour in the field of health care. Keeping in mind the revolution ushered by six sigma concept in corporate world, health care sector may reap the benefits of the same. Six sigma provides a general methodology to describe performance on sigma scale. We aimed to gauge our laboratory performance by sigma metrics. Internal quality control (QC) data was analyzed retrospectively over a period of 6 months from July 2009 to December 2009. Laboratory mean, standard deviation and coefficient of variation were calculated for all the parameters. Sigma was calculated for both the levels of internal QC. Satisfactory sigma values (>6) were elicited for creatinine, triglycerides, SGOT, CPK-Total and Amylase. Blood urea performed poorly on the sigma scale with sigma <3. The findings of our exercise emphasize the need for detailed evaluation and adoption of ameliorative measures in order to effectuate six sigma standards for all the analytical processes.  相似文献   
10.
Gary Ruvkun is a winner of the 2015 Breakthrough Prize in Life Sciences. He is a co-discoverer of microRNAs (with Victor Ambros, University of Massachusetts), regarded as one of the seminal discoveries of 21st century molecular biology. In addition to the Breakthrough Prize, Ruvkun and Ambros have received the Warren Triennial Prize, the Laskar Foundation Award, and numerous other awards and prizes. Professor Ruvkun obtained his PhD from Harvard University, did his postdoctoral research at MIT, and subsequently accepted a faculty position at Harvard, where he is currently Professor of Genetics. His laboratory conducts research on basic cellular processes, using the worm C. elegans as a model system.  相似文献   
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