350 research outputs found

    How Ready Are Your Students for Autonomous Language Learning?

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    Learner autonomy has received attention in the field of language teaching as a result of the trend towards learner-centered approaches in the last decade. However, prior to any intervention to curriculum and materials aiming at increasing autonomy, the level of language learners' readiness for autonomous learning is suggested to be investigated. This study, with this idea in mind, aims to explore 100 English as a Foreign Language (EFL) students' readiness in this specific area through a quantitative approach. Data were gathered by means of Learner Autonomy Readiness Instrument (LARI) (Koçak, 2003). Results showed that participants are not only extrinsically motivated but also intrinsically motivated in some cases. They also apply some metacognitive strategies and their perceptions about taking responsibility depend on the task. Finally, they are willing to engage in outside class activities to learn the language

    Social welfare in one-sided matchings: Random priority and beyond

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    We study the problem of approximate social welfare maximization (without money) in one-sided matching problems when agents have unrestricted cardinal preferences over a finite set of items. Random priority is a very well-known truthful-in-expectation mechanism for the problem. We prove that the approximation ratio of random priority is Theta(n^{-1/2}) while no truthful-in-expectation mechanism can achieve an approximation ratio better than O(n^{-1/2}), where n is the number of agents and items. Furthermore, we prove that the approximation ratio of all ordinal (not necessarily truthful-in-expectation) mechanisms is upper bounded by O(n^{-1/2}), indicating that random priority is asymptotically the best truthful-in-expectation mechanism and the best ordinal mechanism for the problem.Comment: 13 page

    Value of preoperative spirometry to predict postoperative pulmonary complications

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    AbstractIn order to determine the incidence of postoperative pulmonary complications (POPC) and the value of preoperative spirometry to predict pulmonary complications after upper abdominal surgery, 24 women and 36 men (total 60 patients) were studied prospectively (mean age 48·3 years). On the day before the operation and for 15 days after the operation, each patients's respiratory status was assessed by clinical examination, chest radiography, spirometry and blood gas analysis, and patients were monitored for pulmonary complications by a chest physician and a surgeon independently. In this study, postoperative pulmonary complications developed in 21 (35%) patients (pneumonia in 10 patients, bronchitis in nine patients, atelectasis in one patient, pulmonary embolism in one patient). Of 31 patients with abnormal preoperative spirometry, 14 (45·2%) patients showed complications, whereas among 29 patients with normal preoperative spirometry, 7 (24·1%) patients showed complications (P<0·05). The incidence of POPC was higher in patients with advanced age, smoking, preoperative abnormal findings obtained from physical examination of the chest, higher ASA class and longer duration of operation. The sensitivity (0·76) and specificity (0·79) of abnormal preoperative findings obtained from physical examination to predict POPC were higher than abnormal preoperative spirometry (0·67 and 0·56 retrospectively). There was no significant difference between patients with and without pulmonary complications in regard to weight, serum albumin, type of incision, incidence of abnormal preoperative blood gases and duration of postoperative hospital stay. We conclude that POPC is still a serious cause of postoperative morbidity. Multiple risk factors include preoperative abnormal spirometry responsible for development of POPC. If used alone, spirometry has limited clinical value as a screening test to predict POPC after upper abdominal surgery

    Work-related injuries sustained by emergency medical technicians and paramedics in Turkey

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    BACKGROUND: Evaluated in the present study were locations, descriptions, and results of work-related injuries (WRIs) sustained by emergency medical technicians (EMTs) and paramedics in Turkey’s most crowded city, İstanbul. METHODS: After the present study had been accepted by the urban health authority, a questionnaire was emailed to the healthcare personnel of İstanbul’s 195 ambulance stations. RESULTS: Included in the present study were the responses of 901 members of staff (660 EMTs and 241 paramedics), with a mean age of 29.5±6.1 (min: 18; max: 61). The majority of participants (94.9%) had encountered verbal abuse from the public, and 39.8% had encountered physical violence from patients’ relatives. Levels of satisfaction with work in emergency medical services (EMS) was also evaluated, and 510 participants (57.6%) were unhappy. Regarding gender, female employees were more likely to be verbally attacked (p=0.01), while males were more likely to be physically attacked (p=0.001). It was reported that motor vehicle accidents (MVAs) were the most common cause of WRIs (81.4%), followed by needle-stick injuries (52.2%), ocular exposure to blood and other fluids (30.9%), and sharp injuries (22.5%). Only 10.5% (n=95) of WRIs were reported to authorities; 488 (54.2%) of participants just attended to the practice to prevent possible WRIs. CONCLUSION: For paramedics and EMTs, risk of WRI is obviously high. Strategies to decrease and prevent verbal and physical violence should be developed. © 2016 TJTES

    The protective effects of melatonin and vitamin E on antioxidant enzyme activities and epididymal sperm characteristics of homocysteine treated male rats

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    The aims of this study were to investigate the effects of homocysteine (Hcy) on epididymal sperm characteristics, plasma testosterone level and biochemical changes related to oxidative stress and to examine the effects of melatonin (Mlt) or Vitamin E (VE) administration on these parameters in Hcy-treated male rats. In this study, 32 adult male albino rats of Wistar strain were used. The rats were randomly divided into four groups. The first group of rats received only Hcy (0.71 mg/kg/day) intraperitonially (ip) for 6 weeks. The second group of rats was given Hcy along with simultaneous administration of Mlt (1 mg/kg/day) subcutaneously. The third group of rats received Hcy along with simultaneous administration of VE (125 mg/kg/day, ip). The fourth group of rats served as control during 6 weeks and was daily given 0.1mL of physiological saline (NaCl, 0.9%) ip. While the plasma malondialdehyde level significantly (p < 0.05) increased, the plasma superoxide dismutase, glutathione peroxidase and catalase activities significantly (p < 0.05) decreased in Hcy-treated rats when compared to control rats. Furthermore, the epididymal sperm concentration, the percentage of progressive sperm motility and plasma testosterone level were significantly (p < 0.05) lower in Hcy-treated rats than those of the control rats. The simultaneous administration of Mlt or VE to Hcy-treated animals impeded the decrease in the plasma antioxidant enzyme activities, testosterone level, the epididymal sperm concentration and motility. In conclusion, this study indicates that chronic administration of Hcy has the harmful effect on the epididymal sperm characteristics of male rats. The administration of Mlt or VE can prevent adverse effects of Hcy on the plasma antioxidant enzyme activities, testosterone level, epididymal sperm count and motility in male rats

    A delayed diagnosis: stridor secondary to hypocalcemia

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    Hypocalcemia with stridor is a well-known condition in the pediatric age group but has rarely been reported in the elderly. We report an elderly patient who presented with dyspnea and laryngeal stridor attack caused by hypocalcemia. The patient had been suffering from stridor and dyspnea episodes for 2 years, and the etiology had not been determined until the evaluation in our department. The cause of stridor was hypocalcemia secondary to thyroidectomy. Complete resolution of stridor was achieved by calcium replacement therapy

    Lycopene protects against cyclosporine A-induced testicular toxicity in rats

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    Cyclosporine A (CsA)-induced direct failures in hypothalamic–pituitary–gonadal axis and Sertoli cell phagocytic function have been considered for testicular toxicity so far. It has clearly been reported that oxidative stress leads to damage in sperm functions and structure of the testis. Therefore, this study was conducted to demonstrate whether CsA causes testicular and spermatozoal toxicity associated with the oxidative stress, and to investigate the possible protective effect of lycopene against CsA-induced damages in all reproductive organs and sperm characteristics in male rats. While the daily administration of CsA at the dose 15 mg/kg for 21 days significantly decreased the seminal vesicles weight, epididymal sperm concentration, motility, testicular tissue glutathione (GSH), glutathione peroxidase (GSH-Px) and catalase (CAT), diameter of seminiferous tubules and germinal cell thickness, it increased malondialdehyde (MDA) level and abnormal sperm rates along with degeneration, necrosis, desquamative germ cells in testicular tissue. However, the CsA along with simultaneous administration of lycopene at the dose of 10 mg/kg markedly ameliorated the CsA-induced all the negative changes observed in the testicular tissue, sperm parameters and oxidant/antioxidant balance. In conclusion, CsA-induced oxidative stress leads to the structural and functional damages in the testicular tissue and sperm quality of rats and, lycopene has a potential protective effect on these damages

    Attenuation of cyclosporine A-induced testicular and spermatozoal damages associated with oxidative stress by ellagic acid

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    This study was conducted to investigate the possible protective effect of ellagic acid (EA) on cyclosporine A (CsA)-induced testicular and spermatozoal damages associated with oxidative stress in male rats. Forty adult male Sprague–Dawley rats were divided into 4 groups of 10 animals each. Control group was used as placebo. Cyclosporine group received CsA at the dose of 15 mg/kg/day. Ellagic acid group was treated with EA (10 mg/kg/day). Cyclosporine plus ellagic acid group received CsA+EA. Reproductive organs were weighed and epididymal sperm characteristics and histopathological structure of testes were examined along with malondialdehyde (MDA) and glutathione (GSH) levels, glutathione-peroxidase (GSH-Px) and catalase (CAT) activities in testicular tissue. CsA significantly decreased the weights of testes and ventral prostate, epididymal sperm concentration, motility, testicular tissue glutathione (GSH), glutathioneperoxidase (GSH-Px) and catalase (CAT), diameters of seminiferous tubules and germinal cell layer thickness, and it significantly increased malondialdehyde (MDA) level and abnormal sperm rates along with degeneration, necrosis, immature germ cells, congestion and atrophy in testicular tissue. However, the CsA plus EA treatment attenuated all the CsA-induced negative changes observed in the testicular tissue, sperm and oxidant/antioxidant parameters. In conclusion, CsA-induced oxidative stress leads to the structural and functional damages in the testicular tissue and sperm quality of rats, and also EA has a protective effect on these damages

    Attenuating effect of lycopene and ellagic acid on 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced spermiotoxicity and testicular apoptosis

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    This study was conducted to investigate the prophylactic effects of lycopene (LC) and ellagic acid (EA) on 2,3,7,8- tetrachlorodibenzo-p-dioxin (TCDD)-induced testicular and spermatozoal toxicity. These toxicological changes are associated with the oxidative stress and apoptosis in male rats. Forty-eight male rats were allocated to one of six groups of 8 rats each: control, LC, EA, TCDD, TCDD+LC, and TCDD+EA. The control group was treated with 0.5 mL/ rat slightly alkaline solution+0.5 mL/rat corn oil every other day. The LC group was treated with 0.5 mL/rat slightly alkaline solution+0.5 mL/rat corn oil containing 10 mg/kg of LC every other day. The EA group received 0.5 mL/rat corn oil+0.5 mL/rat slightly alkaline solution containing 2 mg/kg of EA every other day. The TCDD group received 0.5 mL/rat corn oil containing 100 ng/kg/day of TCDD+0.5 mL/rat slightly alkaline solution. The TCDD+LC group was treated with 0.5 mL/rat TCDD+0.5 mL/rat LC. The TCDD+EA group was treated with 0.5 mL/rat TCDD+0.5 mL/rat EA. All treatments were made by gavage, and the experimental period was maintained during 8 weeks. Sperm motility, concentration, and abnormal sperm rate in epididymal tissue, testicular tissue lipid peroxidation (LPO), antioxidant enzyme activity, histopathological changes, and apoptosis (i.e., Bax and Bcl-2 proteins) were determined. TCDD exposure resulted in significant decreases in sperm motility, concentration, testicular superoxide dismutase activity, germinal cell-layer thickness, Johnsen’s testicular score, and significant increases in abnormal sperm rate, testicular malondialdehyde, glutathione levels, Bax-positive staining, and Bax-positive apoptotic cell score, along with some testicular histopathological lesions. TCDD treatment did not affect significantly catalase activity. However, combined treatment with LC or EA, in addition to TCDD, prevented the development of TCDD-induced damages in sperm quality, testicular histology, and LPO. Improvements in testicular apoptosis after the administration of LC and EA to TCDD-treated rats were minimal, but not statistically significant. TCDD-induced lipid peroxidation leads to functional and structural damages, as well as apoptosis, in spermatogenic cells of rats. Both LC and EA protected against the development of these effect
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