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The nano-punching characteristics of single-crystalline aluminum are investigated using the quasi-continuum (QC) method. Four variables (i.e., crystal orientation, workpiece thickness, clearance between the punch and the substrate, and the taper angle of punch) are used to explore their effect during the nano-punching process. The shear stress distribution is used to express the punching effect on the punch and on both sides of the substrates. Besides, fracture strength, residual flash, and the atomic displacement vector are observed and discussed regarding the behaviors of the nano-punching process under various conditions. Based on the results, the Al workpiece with the X[111]Y[-110] orientation presents less lattice resistance during the punching process. Besides, the thickness of the workpiece has a significant effect on the punching quality. Workpieces with thickness values of 5 and 10 Å are more suitable for punching, due to stable loading and unloading stress-displacement curves and less residual flash on the cutting surfaces of these workpieces. In contrast, the effect of clearance has less impact on the punching behaviors of thinner workpieces. However, for thicker workpieces (i.e., 15 and 20 Å), a larger clearance will likely cause more residual flash. Furthermore, the taper angle of the punch should not be larger than 10°, otherwise, it might damage the workpiece and the substrate.
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In the present study, the characteristics of graphene/polycrystalline copper nanolaminated (GPCuNL) composites under shear loading are investigated by molecular dynamics simulations. The effects of different temperatures, graphene chirality, repeat layer spacing, and grain size on the mechanical properties, such as failure mechanism, dislocation, and shear modulus, are observed. The results indicate that as the temperature increases, the content of Shockley dislocations will increase and the maximum shear stress of the zigzag and armchair directions also decreases. The mechanical strength of the zigzag direction is more dependent on the temperature than that of the armchair direction. Moreover, self-healing occurs in the armchair direction, which causes the shear stress to increase after failure. Furthermore, the maximum shear stress and the shear strength of the composites decrease with an increase of the repeat layer spacing. Also, the shear modulus increases by increasing the grain size of copper.
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Heart failure (HF) is a common presentation in patients with type 2 diabetes mellitus (T2DM). Previous studies revealed that the HbA1c level is significantly associated with HF. However, little is known about the association between HbA1c variability and HF. We aimed to evaluate the association of mean and variability of HbA1c with HF in patients with T2DM. Using Diabetes Share Care Program data, patients with T2DM who had mean HbA1c (HbA1c-Mean), and HbA1c variability (tertiles of HbA1c-SD and HbA1c-adjSD) within 12-24 months during 2001-2008 were included. The cutoffs of HbA1c-Mean were set at <7%, 7-7.9%, and ≥8%. Hazard ratios (HRs) for HF during 2008-2018 were estimated using Cox proportional hazard models. A total of 3824 patients were included, of whom 315 patients developed HF during the observation period of 11.72 years. The associated risk of HF increased with tertiles of HbA1c variability and cutoffs of HbA1c-Mean. In mutually adjusted models, HbA1c-Mean showed a consistent dose-response association with HF, while the association of HbA1c variability with HF disappeared. Among patients with HbA1c-Mean <7%, the associated risk of HF in patients with HbA1c variability in tertile 3 was comparable to patients with HbA1c-Mean ≥8%. In conclusion, mean HbA1c was an independent predictor of HF and not explained by HbA1c variability. In addition to absolute HbA1c level, targeting on stability of HbA1c in patients with good glycemic control was also important for the development of HF in patients with T2DM.
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AIMS: To test the reliability and validity of the Chinese version of the Insulin Treatment Appraisal Scale (ITAS) questionnaire in patients with type 2 diabetes mellitus (T2DM). METHODS: A total of 200 patients with T2DM were consecutively recruited from the outpatient clinic in Taiwan. The World Health Organization guideline was followed to translate the questionnaire. The internal consistency was assessed by Cronbach's α coefficient and item-total correlations. The construct validity was evaluated by using confirmatory factor analysis, convergent validity, and discriminate validity. RESULTS: The Cronbach's α coefficient for estimates of internal consistency of the total scale was 0.72, and ranged from 0.76 to 0.77 for the subscales. A value of ≥0.40 was considered being substantial. The item-total correlation values were 14 out of 20 items having substantial correlations (4 out of 4 items on the positive appraisal scale and 10 out of 16 items on the negative appraisal scale). The confirmatory factor analysis confirmed both positive and negative factors with total explained variance 33.9% (12.2% for positive subscale and 21.7% for negative subscale). The success rate, calculated from the item-total correlation values, was 70% for the convergent validity (100% for positive subscale and 63% for negative subscale) and 90% for discriminate validity (100% for positive subscale and 88% for negative subscale), respectively. Both the ceiling effect and floor effect were 0%. CONCLUSIONS: The Chinese version of the ITAS questionnaire is a valid and reliable instrument for measuring the perceptions of insulin injection in patients with T2DM.
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Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/psicologia , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Inquéritos e Questionários/normas , Idoso , Instituições de Assistência Ambulatorial , Povo Asiático , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/normas , Reprodutibilidade dos Testes , Taiwan , Tradução , Organização Mundial da SaúdeRESUMO
BACKGROUND: Bullous pemphigoid (BP) is an autoimmune blistering skin disorder with unknown etiology. Evidence revealed that dipeptidyl peptidase IV inhibitors (DPP4i) may increase the associated risk. This study aimed to evaluate the relationship of BP with the administration of DPP4i and other risk factors in patients with type 2 diabetes mellitus (T2DM). METHODS: Using the Taiwan National Health Insurance Database (NHIRD) from 2009 to 2013, we identified patients with T2DM and the use of DPP4i 12â¯weeks or greater as a DPP4i cohort and patients with T2DM who never use DPP4i as a control cohort. They were frequency matched on gender and age within 5â¯years at a ratio of 1:2. The Cox proportional hazard regression model was used to estimate the hazard ratios (HRs) and confidence intervals (CIs) for the cohorts. RESULTS: A total of 14,187 individuals taking DPP4i and 28,374 matched cohorts without taking DPP4i were included. The incidence rate of BP was higher in DPP4i cohort than in control cohort (1.41 vs. 0.59 per 1000 person-years; adjusted HR 2.14, 95% CIâ¯=â¯1.02-4.50). The cumulative event rate of BP in DPP4i cohort was higher than in control cohort (log-rank test, pâ¯=â¯.01). Patients with dementia and taking spironolactone had a higher associated risk to develop BP; lower associated risk in patients taking metformin. CONCLUSIONS: In patients with T2DM, subjects taking DPP4i, having dementia, and taking spironolactone were associated with an increased risk for the development of BP.
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Diabetes Mellitus Tipo 2 , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Penfigoide Bolhoso/epidemiologia , Penfigoide Bolhoso/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Estudos de Coortes , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Penfigoide Bolhoso/induzido quimicamente , Estudos Retrospectivos , Fatores de Risco , Taiwan/epidemiologiaRESUMO
The incidence of heart failure hospitalization (HHF) after taking sitagliptin in type 2 diabetes (T2DM) patients with end stage renal disease (ESRD) on dialysis is unclear. In this population-based cohort study, we identified individuals with T2DM and ESRD on dialysis who were treated with sitagliptin between 2009 and 2011 and randomly selected a control cohort matched by age, sex, duration of T2DM, hypertension medications, use of statin and aspirin, sulfonylureas, glinides, and insulin usage, atherosclerotic heart disease, congestive heart failure and chronic obstructive pulmonary disease at a 1:4 ratio. Multivariable Cox proportional hazards regression analysis was used to evaluate HHF risk. The overall incidence of HHF was higher in the sitagliptin cohort than in the control cohort (1130 vs. 754 per 10000 person-years; adjusted hazard ratio (HR): 1.52, 95% CI = 1.21-1.90). There was a significant trend towards increased HHF risk associated with increased sitagliptin dose (p for trend < 0.01). Subjects at greater risk of HHF after taking sitagliptin were those without severe hypoglycemia, without ACE inhibitors treatment, with history of heart failure or receiving hemodialysis rather than peritoneal dialysis. In conclusion, use of sitagliptin was associated with an increased risk of HHF in patients with T2DM on dialysis.
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Diabetes Mellitus Tipo 2/complicações , Insuficiência Cardíaca/induzido quimicamente , Insuficiência Cardíaca/complicações , Hospitalização , Diálise Renal , Fosfato de Sitagliptina/efeitos adversos , Idoso , Estudos de Coortes , Relação Dose-Resposta a Droga , Feminino , Insuficiência Cardíaca/epidemiologia , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Placebos , Fatores de RiscoRESUMO
AIMS: This study aimed to assess the risk of non-fatal cardiovascular events among patients with type 2 diabetes mellitus (T2DM) who are taking metformin, glimepiride or glyburide. MATERIALS AND METHODS: Using the National Health Insurance Research database in Taiwan, this retrospective cohort study identified 1159 patients with newly diagnosed T2DM from 1998 to 2007, 30 years and older and without a history of cardiovascular disease at baseline. Patients with cancer, liver cirrhosis or chronic kidney disease were excluded. On the basis of prescription, patients were grouped into three medication subcohorts: metformin (N = 595), glimepiride (N = 234) or glyburide (N = 330) monotherapy for 100% of the follow-up period without any oral anti-diabetic agents added or changed, by the end of 2009. Incidence and hazard ratios of non-fatal cardiovascular events including coronary artery disease, peripheral artery disease, stroke and heart failure among these three subcohorts were compared. RESULTS: The overall incidence of non-fatal cardiovascular events was the highest for patients taking glyburide (169.1 per 1000 person-years), followed by for those taking glimepiride and metformin (95.2 and 49.1 per 1000 person-years, respectively). Compared with the adjusted hazard ratio for patients taking glyburide, the adjusted hazard ratio for those taking glimepiride was 0.52 (95% CI 0.40-0.69) and for those taking metformin was 0.31 (95% CI 0.24-0.40). CONCLUSIONS: T2DM patients taking metformin and glimepiride are at lower risk of non-fatal cardiovascular events than those taking glyburide.
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Doenças Cardiovasculares/epidemiologia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Hipoglicemiantes/uso terapêutico , Administração Oral , Adulto , Idoso , Estudos de Coortes , Comorbidade , Doença das Coronárias , Dislipidemias/epidemiologia , Feminino , Glibureto/uso terapêutico , Humanos , Hipertensão/epidemiologia , Incidência , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Estudos Retrospectivos , Compostos de Sulfonilureia/uso terapêutico , Taiwan/epidemiologiaRESUMO
Alcohol has both adverse and protective effects on the individual components of metabolic syndrome (MS). We hypothesize that alcohol consumption increases the risk of developing MS and that the consumption of different types of alcoholic beverages has different effects on the development of MS and its individual components. We enrolled 2358 men for this cross-sectional study. The data were collected from self-reported nutrition and lifestyle questionnaires. Individuals who drank at least once per week for 6 consecutive months were classified as current drinkers. Current drinkers were at a higher risk of developing MS, abdominal obesity, and high triglyceride levels, but they were at a lower risk of developing low levels of high-density lipoprotein cholesterol (HDL-C). The increased risk of developing MS, high triglyceride, and high fasting glucose levels was dose dependent, whereas low HDL-C levels demonstrated a reverse relationship. The dose needed to reduce the risk of having low HDL-C levels was â§50 g/d. This dose, however, resulted in an increased risk of developing high fasting glucose and high triglyceride levels. Consuming mixed types of alcohol increased the risk of developing MS and abdominal obesity. Meanwhile, those who drank liquor or wine had a greater risk of developing high triglyceride or high fasting glucose levels, respectively. In conclusion, alcohol consumption dose-dependently increased the risk of developing MS and some of its individual components while dose-dependently decreasing the risk of developing low HDL-C levels. The type of alcoholic beverage had different effects on the development of the individual components of MS.