Production of chlorine-containing functional group doped graphene powders using Yucel's method as anode materials for Li-ion batteries

In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries. Cl atoms and ClO_x (x = 2, 3 or 4) groups, confirmed by X-ray photoelectron spectroscopy analysis, were covalently doped into the graphene powder network to increase the defect density in the graphene framework and improve the electrochemical performance of Li-ion batteries. The microscopic properties of the Cl-doped graphene powder were investigated by scanning electron microscopy and transmission electron microscopy (TEM) analyses. TEM analysis showed that the one-layer thickness of the graphene was approximately 0.33 nm. Raman spectroscopy analysis was carried out to determine the defect density of the graphene structures. The G peak obtained in the Raman spectra is related to the formation of sp² hybridized carbons in the graphene-based powders. The 2D peak seen in the spectra shows that the synthesized graphene-based powders have optically transparent structures. In addition, the number of sp² hybridized carbon rings was calculated to be 22, 19, and 38 for the Cl-GP1, Cl-GP2, and Cl-GOP samples, respectively. As a result of the charge/discharge tests of the electrodes as anodes in Li-ion batteries, Cl-GP2 exhibits the best electrochemical performance of 493 mA h g⁻¹ at a charge/discharge current density of 50 mA g⁻¹.

In this study, the one-step electrochemical preparation of chlorine doped and chlorine-oxygen containing functional group doped graphene-based powders was carried out by Yucel''s method, with the resultant materials used as anode materials for lithium (Li)-ion batteries.     

Is Endocan a Novel Diagnostic Marker for the Severity of Bronchopulmonary Dysplasia in Very Low Birth Weight Infants?

IntroductionEndocan levels were found to be associated with severity and mortality of the respiratory system diseases.ObjectiveWe aimed to figure out whether endocan was an important marker for the diagnosis, severity and follow-up of bronchopulmonary dysplasia (BPD).Materials and methodsInfants with moderate/severe BPD, and who required hydrocortisone treatment were included in the study group. Infants without BPD were allocated in the control group. Endocan levels were compared between the control group and the study group, and before and after the treatment in the study group.ResultsA total of 148 infants, 74 infants in the control group and 74 infants in the BPD group, were included. The endocan level was higher in the BPD group than in the control group (P = .001). Endocan levels before treatment in the BPD group was found to be higher than endocan level after treatment (P = .021).ConclusionOur study found that endocan levels increased in moderate/severe BPD. Serum endocan levels may be a safe and novel indicator for the follow-up of response to treatment and the prognosis of the severity of the disease.     

The effect of oral and parenteral vitamin D supplementation in the elderly: a prospective, double-blinded, randomized, placebo-controlled study

Hypovitaminosis D in the elderly causes falls and fractures as a result of impaired neuromuscular functions and also may be a reason for nonspecific musculosceletal pain. The aim of this study is to investigate the benefits of a single dose per os or parenterally administrated vitamin D on increasing the quality of life and functional mobility and decreasing the pain in the elderly. The community-dwelling elderly subjects over 65?years age were included in the study. The subjects were given 300.000?IU Vitamin D via per os and parenteral route and assessed after 4?weeks. The serum creatinine, calcium, phosphorous, ALT, ALP, 24-h urine calcium excretion, PTH, and vitamin D levels, as well as VAS (visual analog scale) for pain assessment, functional mobility with TUG (timed up and go test) and quality of life with SF-36 before and after the treatment were evaluated. The serum vitamin D levels were measured by the RIA method. The subjects were divided into four groups each consisting of 30 subjects. The 1st group took i.m. vitamin D, the 2nd group took i.m. placebo, the 3rd group took p.o. vitamin D, and the 4th group took p.o. placebo. The mean age of all the participants was 70.1?±?4.3?years. There was no difference in the age and gender between the groups (P?>?0.05). After treatment, the PTH level of first group was decreased (P?=?0.0001) and the vitamin D level increased (P?=?0.0001) significantly. In the third group, the PTH level of first group was decreased (P?=?0.0001) and the vitamin D level increased (P?=?0.004) and the 24-h calcium excretion in urine (P?=?0.015) increased significantly. When the pain, the functional mobility, and the quality of life were evaluated, in the first group, the TUG (P?=?0.0001) and the VAS (P?=?0.0001) decreased significantly, whereas the SF-36 subtitles: physical functioning (P?=?0.0001), role physical (0.006), bodily pain (P?=?0.0001), general health (P?=?0.007), social functioning (P?=?0.05), and mental health (P?=?0.048) increased significantly. In group two, the VAS (P?=?0.001) decreased, the role physical (P?=?0.009), and role emotional (P?=?0.034) increased significantly; In group three, the TUG (P?=?0.0001) and the VAS (P?=?0.002) decreased, whereas the physical function (P?=?0.0001) and role physical (0.001) increased significantly; In group four, the VAS (P?=?0.007) decreased significantly. The megadose vitamin D administration increases quality of life, decreases pain, and improves functional mobility via po or im route in the elderly.     

Serum leptin and cholesterol levels in patients with bipolar disorder

Low cholesterol levels have been reported in patients with manic episodes. Leptin seems to be strongly associated with lipid metabolism. In the present study, therefore, serum total cholesterol and leptin levels were compared in 16 patients with manic episodes, 16 with bipolar I disorder in full remission and 16 healthy controls. The serum total cholesterol and leptin levels were measured and Young Mania Rating (YMRS) and Hamilton Depression Rating Scales (HAM-D) were administered for each subject. Both the patients with manic episodes and the patients with bipolar I disorder in full remission had markedly low serum cholesterol and leptin levels compared with controls, though the difference was more obvious in patients with manic episodes. In addition, there were negative correlations between YMRS scores and serum cholesterol or leptin levels in the patients with manic episodes. Our results suggest that the patients with manic episodes and those with bipolar I disorder in full remission seem to be associated with decreased serum cholesterol and leptin levels.     

Atypical meningioma and extensive calvarium defects in neurofibromatosis type 1

A 9-year-old girl with neurofibromatosis type 1 (NF1) presented with a massive atypical meningioma and calvarial defect. Skull radiographs and cranial CT showed an extensive lytic bone lesion at the vertex. MRI demonstrated a large mass invading the calvarium and sagittal sinus. The histopathological and immunohistochemical diagnosis of the resected mass was atypical meningioma. To our knowledge, this is the first case of NF1 associated with atypical meningioma and massive calvarial defect in a child.     

Clinical spectrum of acute abdominal pain in Turkish pediatric patients: A prospective study

Abstract Background : The aim of the present study was to determine the prevalence, associated symptoms, and clinical outcomes of children with acute abdominal pain who had been admitted to an emergency department. Methods : Children aged between 2 and 16 years who presented to the emergency department of Cerrahpa?a Medical School, Istanbul University between July 2001 and August 2002 with acute abdominal pain were enrolled in this study. A questionnaire was completed each patient admitted to our pediatric emergency unit for acute abdominal pain. Data collected included presenting signs and symptoms, the hospital follow up for all children who returned within 10 days, test results, and telephone follow up. Results : The number of children referred to the emergency department was 7442, with 399 (5.4%) of these having acute abdominal pain. The mean age of the study population was 6.9 ± 3.5 years, and 201 of the patients were male. The five most prevalent diagnoses were: (i) upper respiratory tract infection and/or complicated with otitis media or sinusitis (23.7%); (ii) abdominal pain with uncertain etiology (15.4%); (iii) gastroenteritis (15.4%); (iv) constipation (9.4%); and (v) urinary tract infection (8%). The most common associated symptoms were decreased appetite, fever and emesis. Because of follow‐up deficiency the progress of 28 patients was not obtained. Eighty‐two children were referred to the department of pediatric surgery, but only 17 of 82 (20.7%) required surgical intervention (15 of these 17 for appendicitis). Eleven patients returned within 10 days for re‐evaluation, but the initial diagnosis was not changed. The complaints of 57 patients with uncertain etiology were resolved within 2 days. Conclusions : An acute complaint of abdominal pain was usually attributed to a self‐limited disease. However, the percentage of surgical etiology is not negligible.     

Matrix metalloproteinase expression in basal cell carcinoma: relationship between enzyme profile and collagen fragmentation pattern

Matrix metalloproteinases (MMPs) with collagenolytic and gelatinolytic activities are up-regulated in basal cell carcinoma. In the present study we demonstrate that the major collagenolytic enzyme detected is MMP-1 (interstitial collagenase) while gelatinolytic enzymes include both MMP-2 (72-kDa gelatinase A) and MMP-9 (92-kDa gelatinase B). Significant fractions of all three enzymes are present as active forms. In spite of the fact that high levels of gelatinolytic enzymes are present, the major fragmentation products resulting from digestion of intact type I collagen are the 1/4 and 3/4 fragments (products of MMP-1-mediated digestion). Thus, it appears that the gelatinolytic enzymes are not capable of degrading the collagen fragments as rapidly as they are produced. Since previous studies have demonstrated that interaction of interstitial fibroblasts with high molecular weight fragments of type I collagen leads to increased MMP production, the present results suggest a mechanism underlying altered function of stromal elements in the connective tissue adjacent to the growing neoplasm.     

Perceptions of first and third year medical students on self-study and reporting processes of problem-based learning

Background  

The objective of this study is to investigate the perceptions of first and third year medical students on self-study and reporting processes of Problem-based Learning (PBL) sessions and their usage of learning resources.