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21.
The aim of the present study was to compare cardiac structure as well as global and regional cardiac function in athletes with and without myocardial fibrosis (MF). Cardiac magnetic resonance imaging with late gadolinium enhancement was used to detect MF and global cardiac structure in nine lifelong veteran endurance athletes (58?±?5 years, 43?±?5 years of training). Transthoracic echocardiography using tissue-Doppler and myocardial strain imaging assessed global and regional (18 segments) longitudinal left ventricular function. MF was present in four athletes (range 1–8?g) and not present in five athletes. MF was located near the insertion points of the right ventricular free wall on the left ventricle in three athletes and in the epicardial lateral wall in one athlete. Athletes with MF demonstrated a larger end diastolic volume (205?±?24 vs 173?±?18?ml) and posterior wall thickness (11?±?1 vs 9?±?1?mm) compared to those without MF. The presence of MF did not mediate global tissue velocities or global longitudinal strain and strain rate; however, regional analysis of longitudinal strain demonstrated reduced function in some fibrotic regions. Furthermore, base to apex gradient was affected in three out of four athletes with MF. Lifelong veteran endurance athletes with MF demonstrate larger cardiac dimensions and normal global cardiac function. Fibrotic areas may demonstrate some co-localised regional cardiac dysfunction, evidenced by an affected cardiac strain and base to apex gradient. These data emphasize the heterogeneous phenotype of MF in athletes.  相似文献   
22.
This article describes a classroom tool to teach the impact of supply chain disruptions and mitigation strategies based on information sharing and collaboration. The tool is an adaptation of the Beer Distribution Game, is easy to play, and can be hosted online or on local servers. The game considers several scenarios based on the location of the disruptions (i.e., upstream or downstream) and the information available to supply chain partners. Students play the roles of managers who make ordering decisions in a serial supply chain and experience decision‐making under disruptions.  相似文献   
23.
ABSTRACT

This paper presents results from a small-scale study of third-year Instrumentation and Control Engineering (n?=?37) at the University of Plymouth. The aim of the study was to enhance student learning and increase participation via the use of clickers. Clickers allow for student participation anonymously. The lecture content was modified to embed clicker questions at regular intervals to test knowledge, understanding and cognitive skills. Largely, the students preferred interactive lectures to traditional didactic lectures and using clickers increased student engagement and participation. Interestingly, compared to assessment results from the previous year, the increased level of engagement did seem to lead to an overall improvement in grades of approximately 10% in the subject of Control Engineering. However, in Instrumentation, the average fell by approximately 20%. One possible contributory factor of this drop could be the changed exam format for Instrumentation only. This year, the multiple choice section was removed from the Instrumentation examination paper. Furthermore, an analysis of variance showed that in addition to using clickers in the lectures, attendance plays a key role. Results of this small-scale study show that for a more complex subject like Control, student learning, engagement and attainment can increase by the use of clickers.  相似文献   
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25.
Despite ample sunshine, 50–90% Indian children have Vitamin D deficiency (VDD). This enigma of widespread VDD needs exploration especially among under-fives as physiological variations in Vitamin D Binding Protein (VDBP) levels could be potential confounders in the interpretation of total 25-hydroxyvitamin D [25(OH)D]. However, there is scarce information about relevance of VDBP levels in under-five age group. We therefore, explored association of VDBP levels among 1–5 year old children with VDD. Serum levels of 25(OH)D, VDBP, calcium, parathyroid hormone (PTH) and alkaline phosphatase were estimated in 210 apparently healthy children in the age group of 1–5 years. VDD was defined as serum 25(OH)D levels < 20 ng/ml as per the IOM classification. VDBP levels were classified as low if levels were < 168 μg/ml as per the kit. The prevalence of VDD was 79.5% (n = 167) and VDBP levels were low in 48.6% (n = 102) of children. 25(OH)D levels correlated positively with VDBP (r = 0.298, p = 0.0001). A significant number of children (52.7%) with VDD had low VDBP (p = 0.015). and despite adequate sun exposure, 43% of children showed VDD and 56.6% had low VDPB levels. The low VDBP levels largely explain low 25OHD levels without necessarily implying VDD. It may add a new dimension for better understanding of widespread VDD among under-five children. It thus, points towards the need for redefining cut offs and complete evaluation of vitamin D status among under-fives including VDBP.  相似文献   
26.
Arsenic a metalloid and environmental contaminated has been found to be associated with public health problems in the affected areas. It is naturally occurred in groundwater and its accumulation in plant and animals leads to toxicity in several tissues most notably hepatic organ. Arsenic exposures (3 mg/kg body weight/day for 30 days) in mice exhibited increased arsenic and Zn levels in hepatocytes associated with enhanced oxidative stress in hepatocytes while there were no significantly changes were observed in Cu level. An increase in the lipid peroxidation and decrease in the levels of reduced glutathione and activity of superoxide dismutase, catalase, and glutathione peroxidase were observed in arsenic treated mice as compared to controls. Arsenic exposure in mice also caused a significant change in serum biomarkers in the SGOT, SGPT and creatinine as compared to the controls. There were no significant changes in the serum levels of total protein in these mice. Co-administration of arsenic and fruit extract of amla (500 mg/kg body weight/day for 30 days) caused a significant reduction of arsenic transference associated with significantly decreases hepatic arsenic levels and balanced the antioxidant enzyme and levels of serum hepatic enzymes like SGOT and SGPT. The results of the present study clearly demonstrate the antioxidant property of amla that could be responsible for its protective efficacy in arsenic induced hepatic toxicity.  相似文献   
27.
Type 2 diabetes mellitus consists of dysfunctions characterized by hyperglycemia and resulting from combination of resistance to insulin action and inadequate insulin secretion. Most of diabetic patients report significant gastrointestinal symptoms. Entire GI tract can be affected by diabetes from oral cavity to large bowel and anorectal region. Proteins, carbohydrates, fats, and most fluids are absorbed in small intestine. Malabsorption may occurs when proper absorption of nutrients does not take place due to bacterial overgrowth or altered gut motility. The present study was planned to measure various malabsorption parameters in type 2 diabetic patients. 175 patients and 175 age and sex matched healthy controls attending Endocrinology Clinic in PGI, Chandigarh were enrolled. Lactose intolerance was measured by using non-invasive lactose hydrogen breath test. Urinary d-xylose and fecal fat were estimated using standard methods. Orocecal transit time and small intestinal bacterial overgrowth were measured using non-invasive lactulose and glucose breath test respectively. Out of 175 diabetic patients enrolled, 87 were males while among 175 healthy subjects 88 were males. SIBO was observed in 14.8 % type 2 diabetic patients and in 2.8 % of controls. There was statistically significant increase (p < 0.002) in OCTT in type 2 diabetic patients compared with controls. OCTT was observed to be more delayed (p < 0.003) in patients who were found to have SIBO than in patients without SIBO. Lactose intolerance was observed in 60 % diabetic patients and 39.4 % in controls. Urinary d-xylose levels were also lower in case of diabetic patients but no significant difference was found in 72 h fecal fat excretion among diabetic patients and controls. Urinary d-xylose and lactose intolerance in SIBO positive type 2 diabetic patients was more severe as compared to SIBO negative diabetic patients. From this study we can conclude that delayed OCTT may have led to SIBO which may have instigated the process of malabsorption among type 2 diabetic patients.  相似文献   
28.
Research in physics education indicates that the use of multiple representations in teaching and learning helps students become better problem-solvers. We report on a study to investigate students' difficulties in solving mechanics problems presented in multiple representations. We conducted teaching/learning interviews with 20 students in a first-semester calculus-based physics course which covered introductory classical mechanics. Each student was interviewed four times during the semester, each time after they had completed an exam in the course. During these interviews, students were asked to solve a problem they had seen in the exam, followed by problems that differed in the type of representation from the exam problems. Students were provided verbal hints to solve the new problems. We discuss the common difficulties students encountered when attempting to solve problems in different representations and some common themes in students' performance.  相似文献   
29.
The development of widely applicable point-of-care sensing and diagnostic devices can benefit from simple and inexpensive fabrication techniques that expedite the design, testing, and implementation of lab-on-a-chip devices. In particular, electrodes integrated within microfluidic devices enable the use of electrochemical techniques for the label-free detection of relevant analytes. This work presents a novel, simple, and cost-effective bench-top approach for the integration of high surface area three-dimensional structured electrodes fabricated on polystyrene (PS) within poly(dimethylsiloxane) (PDMS)-based microfluidics. Optimization of PS-PDMS bonding results in integrated devices that perform well under pressure and fluidic flow stress. Furthermore, the fabrication and bonding processes are shown to have no effect on sensing electrode performance. Finally, the on-chip sensing capabilities of a three-electrode electrochemical cell are demonstrated with a model redox compound, where the high surface area structured electrodes exhibit ultra-high sensitivity. We propose that the developed approach can significantly expedite and reduce the cost of fabrication of sensing devices where arrays of functionalized electrodes can be used for point-of-care analysis and diagnostics.  相似文献   
30.
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