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During train operation in a wheel-rail system, the service lives of the wheel and rail materials are heavily influenced by microstructural evolution. This study investigated the relationship between microstructural evolution and the wear properties of U71Mn rail steel under conditions of dry sliding wear using an MRH-5A wear tester. The results demonstrated that tribological white etching layers (T-WELs), which comprise nanocrystalline α-Fe and fine carbide, are formed after a certain number of cycles. The T-WEL thickness increased with the number of cycles; however, more cycles caused T-WEL flaking, which resulted in a reduced T-WEL length. The high microhardness of T-WELs (approximately 950 HV) is mainly attributed to ferrite grain refinement and cementite dissolution. During initial wear, the existence of grinding marks on the surfaces of the samples indicated an obvious increase in the wear loss of the steel. The high microhardness of the T-WELs can enhance wear resistance; thus, as the number of cycles was increased, the wear loss of the steel was reduced. At this point, an adhesive wear mechanism acted on the rail steel. The formation of fatigue cracks at the interface between the T-WEL and the plastic deformation layer induces T-WEL flaking, which increases wear loss. Consequently, after 6000 cycles, wear loss increased as the wear mechanism changed to fatigue wear. It is confirmed that T-WEL flaking is the primary cause of wear failure in U7Mn rail steel.

In actual wheel–rail systems, a nonuniform microstructure of the wheel and rail materials is a serious problem. A double-disk rolling wear test device was used to study the influence of the nonuniform microstructure on the wear properties of wheel materials in the present study. The results show that the microstructure of the sample 1 includes proeutectoid ferrite, pearlite, and upper bainite, which is a nonuniform microstructure. By contrast, the microstructure of sample 2 contains only proeutectoid ferrite and pearlite. During wear tests, with the increasing number of test cycles, the weight loss of the sample 1 is consistently larger than that of the sample 2. A similar trend is observed with respect to deformation of the plastic layer. For the sample 1, fatigue cracks mainly propagate along the interface between the upper bainite and pearlite, leading to rapid wear failure; the main wear mechanism changes from spalling to fatigue with the increasing number of cycles. For the sample 2, the main wear mechanism changes from adhesive wear to fatigue wear with increasing number of cycles.

A fine-grain layer is produced in high-speed train wheels after machining. In this article, the influence of the fine-grain layer on rolling contact fatigue (RCF) is studied using a GPM-30 fatigue ...

In this work, the influence of original microstructure on wear property of ER9 wheel steel is studied by GPM-40 rolling wear tester. The pearlite + proeutectoid ferrite (P+F) sample exhibits the lo...

This work investigates the effect of abnormal microstructure on rolling contact fatigue (RCF) damage of high-speed railway wheels under service and the formation mechanism of abnormal microstructure by optical microscopy, scanning electron microscopy, transmission electron microscopy, nano indentation and laser-induced break down spectroscopy. Results show that there are large amounts of upper bainite in the wheel tread, which destroyed the uniformity of the microstructures of the wheel matrix. The bainite is composed of ferrite with high density of dislocations and short bar-shaped cementite. The bainite exhibited higher hardness and elasticity but lower plasticity than the matrix microstructure. The incongruity of plastic deformation between upper bainite and matrix microstructures will lead to stress concentration at boundary of the microstructures, thus accelerating the RCF crack initiation and propagation. The formation of upper bainite is caused by carbon segregation. Segregation of carbon element will make the continuous cooling transformation (CCT) curve shift to the right significantly, thus increasing the probability of bainite transformation in segregation zone at higher cooling rate. Therefore, large amounts of upper bainite were formed at wheel tread.

A GPM-30 fatigue machine was used to investigate the influence of surface ultrasonic rolling (SURT) on the rolling contact fatigue (RCF) life of D2 wheel steel. The experimental results present that the RCF life of the grinding processing sample is 4.1 &times, 105 cycles. During the RCF process, the flaking of the fine grain layer and high surface roughness of the grinding processing sample cause the production of RCF cracks. When the samples are treated by SURT with 0.2 MPa and 0.4 MPa, the RCF life is 9.2 &times, 105 cycles and 9.6 &times, 105 cycles, respectively. After SURT, the surface roughness of the samples is reduced, and a certain thickness of gradient-plastic-deformation layer and a residual-compressive-stress layer are produced. These factors lead to the improvement of the RCF property. However, when the static pressure increases to 0.6 MPa during SURT, the RCF life of the sample is reduced during RCF testing. The micro-cracks, which are formed during SURT, become the crack source and cause the formation of RCF cracks, decreasing of the RCF life.

Background and Purpose Combination therapy with dipyridamole and clopidogrel in stroke prevention and long-term outcomes in aspirin-intolerant patients with acute myocardial infarction (AMI) and previous stroke are unknown. This nationwide study analyzed the impact of dipyridamole and clopidogrel on secondary stroke prevention and long-term outcomes in aspirin-intolerant stroke patients after AMI. Methods This was a nationwide, case-control study involving 186,112 first AMI patients, 78,607 of whom had a previous history of stroke. In the final analysis, we included 4637 patients taking clopidogrel alone and 208 patients using a combination of clopidogrel and dipyridamole. Results The 12-year survival rate was not different between clopidogrel and clopidogrel–dipyridamole groups (log-rank p = 0.6247). Furthermore, there were no differences in event-free survival after stroke (log-rank p = 0.6842), gastrointestinal (GI) bleeding (log-rank p = 0.9539), or intracerebral hemorrhage (ICH; log-rank p = 0.6191) between the two groups. Dipyridamole did not contribute significantly to AMI survival (hazard ratio 0.98, 95% confidence interval 0.84–1.15), and did not show benefits in any of the subgroups regardless of sex, age (younger or older than 75 years), comorbidities, percutaneous coronary intervention, or medications. Conclusion No differences were observed in the 12-year survival rate between clopidogrel and clopidogrel–dipyridamole groups. The two groups had balanced event-free survival in recurrent stroke, ICH, GI bleeding, and myocardial infarction.

In this paper, the surface microstructure and wear property of D2 wheel steel under sliding wear condition were studied by MRH-30 sliding wear tester. After testing, a transmission electron microscope (TEM), scanning electron microscope (SEM) with electron backscatter diffraction (EBSD), and micro-hardness testers were used to characterize the surface microstructure of samples with different cycles. The results show that the wear losss samples are increased as the increase of cycles, and the wear loss of wheel samples is higher than that of rail samples. The surface hardness and thickness of deformation layer of wheel samples are increased as the cycles increase. After sliding wear, the samples surfaces form the white etching layer with the thickness of several microns. Through the analysis of surface microstructure of sample with 12,000 cycles, the lamellar cementite in pearlite is fragment into cementite particles with the decrease of depth from surface, and the cementite is dissolved at surface to lead to the form of white etching layer. The ferrite grains are refined gradually and the fraction of high angle grain boundary is increased with the decrease of depth from surface. The nanosgrains layer of ferrite grains with 5 μm thickness is formed. According to the result of finite element simulation of contact surface temperature, the formation of surface nanograins and the dissolution of cementite are caused by the severe plastic deformation. The fiber structure of samples is formed after sliding wear, with direction of .

In this work, the relationship between rolling contact fatigue (RCF) failure and the microstructure of D2 wheel steel was studied using a GPM-30 fatigue tester under oil lubrication conditions. The microstructural evolution during the RCF process can be divided into three stages: In the first stage, the misorientation of the proeutectoid ferrite is 2°–10°, the ferrite phase in pearlite is less than 2°, and the dislocation density is low. In the second stage, with the increase in cycles, the misorientation of the proeutectoid ferrite increases to more than 10°, and the ferrite phase in pearlite increases to 2°–10°. In the third stage, the misorientation of the ferrite phase in pearlite increases to more than 10°, the ferrite phase is divided into fine grains, and the dislocation density is high. RCF cracks are formed in the third stage. Crack initiation is ascribed to the refinement of the surface ferrite phase and proeutectoid ferrite and the increase in dislocation density. RCF cracks are initiated and propagate primarily at the interface of pearlite/proeutectoid ferrite and in proeutectoid ferrite.

To investigate the worn-surface microstructure and fatigue cracks in D2 wheel steel under the pure rolling and 0.5% slip ratio conditions, a rolling wear test using a GPM-40 wear machine to simulate the wheel/rail operation was performed. After testing, a transmission electron microscope, a scanning electron microscope with electron backscatter diffraction, and micro-hardness testers were used to characterize the microstructure and fatigue cracks. The surface microstructure and hardness of the pure rolling sample were in a steady state after 8 × 104 cycles; however, the 0.5% slip ratio sample reached a steady state after 7 × 103 cycles. Regardless of whether the test uses the slip ratio, the orientation of lamellar pearlites gradually became parallel to the surface and a portion of lamellar cementites was fragmented and dissolved during the formation of steady-state microstructure. The slip ratio accelerates this process. The hardening mechanism of the samples shows a decrease in the lamellar spacing of pearlite and the refinement of proeutectoid ferrite (PF). As the number of cycles increased, plastic deformation of samples became increasingly severe and the wear mechanism of the samples was fatigue wear in steady state. The sample surfaces formed shallow cracks, which gradually peeled off. The slip ratio accelerated the initiation and propagation of fatigue cracks because of the high friction stress on the contact surface. Most fatigue cracks initiated at the interface of pearlite and PF and in the PF region.

Relationship between radiation-induced skin ulceration (RSU) and variables in percutaneous coronary interventions (PCI) was rarely reported. RSU is a severe complication in PCIs, especially for chronic total occlusion (CTO) lesions. We investigated the RSUs and their risk factors in patients receiving CTO PCIs over a 2-year period. Data were analyzed using chi-square tests, t-tests and receiver operating characteristic (ROC) curve. Of 238 patients, 11 patients (4.6%) had RSUs all at right upper back. RSUs were significantly associated with use of left anterior oblique (LAO) views (100% vs. 47.1%, p 120, 180, or 240 minutes (p

Proton pump inhibitor can effectively prevent recurrent peptic ulcers among atherosclerotic patients receiving clopidogrel monotherapy. However, the interaction between proton pump inhibitors and clopidogrel has raised concerns over the safety of combined use of the two medicines in clinical practice. The aims of this randomized-controlled, double-blind and double-dummy trial were to investigate the efficacy of histamine-2 receptor antagonist (H2RA) in the prevention of recurrent peptic ulcer in patients undergoing thienopyridine monotherapy.From January 2012 to 2016, long-termed thienopyridine users with a peptic ulcer history who did not have peptic ulcers at initial endoscopy were randomly assigned to receive either famotidine (40 mg, before bedtime) or placebo (before bedtime) for 6 months. Follow-up endoscopy was performed at the end of the 6th month and whenever dyspepsia, hematemesis, or melena occurred.The cumulative incidence of recurrent peptic ulcer during the 6-month period was 7.0% in famotidine group (n=114) and 11.4% in the placebo group (n=114). The two patient groups had comparable cumulative incidence of peptic ulcer (difference, 4.4%; 95% confidence interval (CI), -11.7 to 2.9%; P=0.239). Additionally, there was no difference in the cumulative incidence of ulcer bleeding (2.6% vs. 1.8%; difference, 0.8%; 95% CI, -0.6 to 2.4%, P=1.000) between famotidine and placebo groups. However, the former had a lower incidence of gastroduodenal erosion than the latter (21.1% vs. 36.8%; difference, 15.7%; 95% CI, -27.3 to -4.1%; P=0.013).Famotidine cannot decrease the incidence of peptic ulcer or ulcer bleeding in thienopyridine users with atherosclerotic disease and a history of peptic ulcer.

Background Use of statin has been associated with reduced risk of cardiovascular diseases events and mortality. However, in patients with end-stage renal disease (ESRD), the protective effects of statin are controversial. To evaluate the impact of chronic statin use on clinical outcomes of patients with acute myocardial infarction (AMI) with ESRD. Methods We enrolled 8056 patients with ESRD who were initially diagnosed and admitted for first AMI from Taiwan’s National Health Insurance Research Database. Of which, 2134 patients underwent statin therapy. We randomly selected and use age, sex, hypertension, diabetes mellitus (DM), peripheral vascular diseases (PVD), heart failure (HF), cerebrovascular accidents (CVA), chronic obstructive pulmonary disease, matched with the study group as controls (non-stain user). We compared the effects of statin use in term of all-cause death among patients with AMI with ESRD. Results Statin use resulted in a significantly higher survival rate in patients ith AMI with ESRD compared with non-statin users. After adjusted the comorbidities the male patients and patients with DM, PVD, HF and CVA had lower long-term survival rate (all p Conclusion Among patients with ESRD with AMI, statin therapy was associated with reduced all-cause mortality.

To investigate the relationship between surface microstructure and wear mechanism in D2/U71Mn wheel-rail material under different contact stress conditions, rolling wear tests using a GPM-40 wear machine to simulate the wheel-rail operation was performed. After wear tests, an optical microscope (OM), scanning electron microscope (SEM) and micro-hardness testers were used to characterize the microstructure and fatigue wear cracks. The results show that the thickness of the plastic deformation layer and surface hardness is increased with the increase of contact stress. Under high contact stress condition (1200 MPa), the severe plastic deformation layer led to the formation of fatigue wear of wheel-rail samples. Under a contact stress of 700 MPa, the wear mechanism of samples is adhesive wear and wear rate is low. With the increase of contact stress, the fatigue cracks are gradually severe. Under a contact stress of 1200 MPa, the wear mechanism of samples becomes fatigue wear and the fatigue wear cracks cause the increase of wear rate. The fatigue wear can accelerate the wear failure of wheel-rail samples. The fatigue wear cracks of wheel samples are severer than that of rail samples due to both the rate of plastic strain and the content of proeutectoid ferrite.

Pulmonary arterial hypertension (PAH) is characterized by pulmonary arterial proliferation and remodeling, resulting in a specific increase in right ventricle systolic pressure (RVSP) and, ultimately right ventricular failure. Recent studies have demonstrated that caffeic acid phenethyl ester (CAPE) exerts a protective role in NF-&kappa, B-mediated inflammatory diseases. However, the effect of CAPE on PAH remains to be elucidated. In this study, monocrotaline (MCT) was used to establish PAH in rats. Two weeks after the induction of PAH by MCT, CAPE was administrated by intraperitoneal injection once a day for two weeks. Pulmonary hemodynamic measurements and pulmonary artery morphological assessments were examined. Our results showed that administration of CAPE significantly suppressed MCT-induced vascular remodeling by decreasing the HIF-1&alpha, expression and PDGF-BB production, and improved in vivo RV systolic performance in rats. Furthermore, CAPE inhibits hypoxia- and PDGF-BB-induced HIF-1&alpha, expression by decreasing the activation of the AKT/ERK pathway, which results in the inhibition of human pulmonary artery smooth muscle cells (hPASMCs) proliferation and prevention of cells resistant to apoptosis. Overall, our data suggest that HIF-1&alpha, is regarded as an alternative target for CAPE in addition to NF-&kappa, B, and may represent a promising therapeutic agent for the treatment of PAH diseases.

Device-to-device (D2D) communications achieve a considerable proximate gain by means of single hop, which can improve the link spectrum efficiency of cellular networks by reusing the shortage licensed spectrum. However, co-channel interference will become a serious challenge that will influence the performance of both D2D and cellular links if it cannot be processed appropriately. The existing solutions are limited to single radio access technology (RAT), and they all involve tradeoffs between the available terminal density and the link spectrum efficiency. In this paper, we propose the offloading scheme of D2D communications on multi-RATs, which can achieve high link spectrum efficiency without sacrificing the available terminal density. The multi-RATs offloading scheme will achieve maximum link spectrum efficiency with the retention probability as a parameter that is formulated for a non-convex function. Considering the main factor of different scenarios that refer to high and sparse available terminal densities, we propose the dynamic adjustment offloading algorithm and the sparse-density optimization offloading algorithm to solve the non-convex problem. In addition, because we use the closed form of the stochastic geometry, the optimum offloading algorithms possess predictable features that do not break the established D2D links when a new link is applied. Finally, the simulation results show that the performance of the coverage probability and link spectrum efficiency is both greatly improved compared with the traditional D2D communications without exploiting the offloading scheme. More significantly, the spectrum efficiency of cellular links is also improved effectively due to the offloading effect.

Acute cardiomyopathy is a health problem worldwide. Few studies have shown an association between acute cardiomyopathy and low vitamin D status. Paricalcitol, a vitamin D receptor activator, clinically benefits patients with advanced kidney disease. The effect of paricalcitol supplement on cardiac remodeling in cardiomyopathic rats is unknown. This experimental study investigated the effect of paricalcitol in rats with cardiomyopathy induced by isoproterenol.Prospective, randomized, controlled experimental study.Hospital-affiliated animal research institution.Eight-week-old male Wistar-Kyoto rats.Male Wistar-Kyoto rats were first injected intraperitoneally with isoproterenol to create a rat model of acute cardiomyopathy. Then paricalcitol was administered intraperitoneally to isoproterenol-injected rats at a dosage of 200 ng three times a week for 3 weeks. Relevant cardiomyopathy-related variables were measured regularly in three groups of rats, controls, isoproterenol, and isoproterenol plus paricalcitol. Rat hearts were obtained for evaluation of cardiac fibrosis using Masson trichrome staining and commercially available software, and evaluation of cell transition using immunofluorescence staining analysis.Isoproterenol infusions generated significant cardiac fibrosis (p0.001). Subsequent paricalcitol treatment attenuated the isoproterenol-induced cardiac fibrosis (p = 0.006). Fluorescence showed colocalization of endothelial and fibroblast cell markers (cluster differentiation 31 and α-smooth muscle actin, respectively) in the isoproterenol-treated hearts. Paricalcitol injections attenuated the isoproterenol-induced fluorescence intensity of two cell markers (p0.01).Paricalcitol injections may ameliorate isoproterenol-induced cardiac fibrosis possibly through regulating cell transition.

Background The outcomes of drug-eluting stent (DES) versus bare-metal stent (BMS) use in patients with diabetic mellitus (DM) and acute coronary syndrome (ACS) are rarely reported in Taiwan. This study aimed to investigate the 1-year cardiovascular outcomes of DESs versus BMSs implanted in Taiwanese patients with DM and ACS. Methods For this study, we collected and analyzed patient information from the database of the Taiwan ACS Full Spectrum registry regarding characteristics and cardiovascular events in participants with DM and ACS who received implantation of either BMS (BMS group) or DES (DES group) from October 2008 to January 2010. Results We found that several characteristics significantly varied between the groups. Compared with the BMS group ( n = 575), the DES group ( n = 199) had significantly lower rates of in-hospital cardiogenic shock (1.5% vs. 4.9%, p = 0.037) and acute renal failure (0.5% vs. 4.5%, p = 0.008), all-cause mortality (5.0% vs. 8.9%, p = 0.048), and major adverse cardiac events (MACEs) at 1 year (11.1% vs. 18.6%, p = 0.006) with an identical target vessel revascularization (TVR) rate (6.0% vs. 7.3%, p = 0.395). The BMS group had significantly higher risk-adjusted all-cause mortality [hazard ratio (HR) = 2.4, 95% confidence interval (CI) 1.0–5.7; p = 0.048] and MACE (HR = 2.2, 95% CI 1.2–3.9; p = 0.011) at 1 year with identical risks of TVR (HR = 1.3, 95% CI 0.6–2.9; p = 0.505) and nonfatal myocardial infarction (HR = 1.5, 95% CI 0.5–4.4; p = 0.478). Conclusion The results of this study support the use of DES over BMS in Taiwanese patients with DM and ACS, providing the clinical benefits of lower rates of total mortality and MACE, and without increased TVR at 1 year in a real-world setting.

Because nonuniform microstructures may accelerate the wear rate of wheels made from ER8 steel, a wear test was performed on a wheel sample with a nonuniform microstructure, and the wear properties were compared with that of a wheel composed of a uniform microstructure. In addition, the wear mechanism of the wheel with a nonuniform microstructure was analyzed. In addition to the uniform microstructure of pearlite and proeutectoid ferrite, upper bainite was observed in the wheel with a nonuniform microstructure. The upper bainite disrupted the continuity and uniformity of the microstructure. Moreover, owing to the different work hardening mechanisms of upper bainite and pearlite, the plastic deformations of upper bainite and pearlite were incompatible, which induced and promoted the formation of fatigue cracks in the nonuniform microstructure and further accelerated fatigue wear.

In this work, the influence of different original microstructure on the rolling contact fatigue (RCF) property of D2 wheel steel under oil lubrication condition is thoroughly studied by the GPM-30 rolling fatigue tester. Before pre-wear, the RCF life of the tempered sorbite (TS) sample and the lamellar pearlite + proeutectoid ferrite (P + F) sample are 7.2 × 105cycles and 5.4 × 105 cycle, respectively. After pre-wear, the RCF life of the TS sample is 4 times higher than that of the original TS sample. However, the RCF life of the P + F sample is 4 times lower than that of the original P + F sample. After pre-wear, the formation of fatigue wear cracks at the P + F sample surface causes the flaking of hardening layer and acts as a crack initiation site to accelerate the RCF failure. While the hardening layer of the TS sample is not flaked. The formation of hardening layer and the decrease of surface roughness of the TS sample improve the RCF life. During the RCF crack propagation process, the ferrite grains are refined obviously at the edge of cracks due to huge internal stress on the inner wall of the RCF cracks. The thickness of refined ferrite grains of the TS sample at the edge of RCF cracks is higher than that of the P + F sample.

In this work, the effect of pre-wear under air condition on the rolling contact fatigue life (RCF) of D2 wheel steel under oil lubrication was thoroughly studied based on the rolling wear experiment. The results show that dry pre-wear can improve the RCF life of wheel sample under oil lubrication during RCF process before the sample surface forms the fatigue wear cracks during pre-wear process. Dry pre-wear can change largely pre-wear surface, such as increasing surface layer dislocation density, refining ferrite grains, dissolving lamellar cemetite in pearlite, forming fibrous microstructure and reducing surface roughness. These microstructural changes contribute to an improvement of the surface strength and RCF life of samples. However, when fatigue wear occurs on the contact surface during pre-wear process. The fatigue wear crack causes the flaking of hardening layer, and is a RCF crack source to accelerate the formation of the RCF crack. It can lead to reduce the RCF life of the sample.

Objectives: Although the association between systemic infection and cardiovascular events has been identified, uncertainty remains regarding the incidence and prognosis of sepsis in acute myocardial infarction (AMI). The purpose of this research was to assess the impact of sepsis on survival after first AMI. Methods: This was a nationwide cohort study involving the analysis of data from the Taiwan National Health Insurance Research Database for the period 2000–2012, for patients with a primary diagnosis of first AMI. Among the 186 112 prospective patients, sepsis was diagnosed in 13 065 (7.0%). The propensity score matching technique was used to match 13 065 controls to the patients with sepsis and AMI with similar baseline characteristics. Cox proportional hazards regression models, including sepsis, percutaneous coronary intervention (PCI), and comorbidities, were performed to further evaluate the different influences on the mortality risk in patients hospitalized for first AMI. Results: Overall, the 12-year survival rate was lower in AMI patients with sepsis than in those without sepsis (log rank p-value

A number of studies has shown that long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and protein coding genes (PCGs) are involved in various pathophysiological processes and can be used as prognostic biomarkers in cancer patients. The purpose of this study was to find a multidimensional transcriptome signature to predict clinical outcomes in bladder cancer. Using Cox′s proportional hazards regression analysis and the random survival forest algorithm, we mined the expression profile data of 239 bladder cancer patients derived from The Cancer Genome Atlas (TCGA) public database. A signature comprised of two PCGs (ACADS and C1QTNF9B), two lncRNAs (RP11-60L3.1 and CTD-3195I5.3) and two microRNAs (has-miR-3913-1 and has-miR-891a) with highest accuracy prediction (AUC= 0.79 in the training dataset and 0.64 in the test dataset) was selected. The signature had an ability to stratify patients into high- and low-risk groups with significantly different survival rates (median 16.9 vs. 54.9 months, log-rank test Pl0.001) in the training dataset, and its performance was validated for risk stratification in the test dataset (median 18.2 vs. 58.9 months, log-rank test P=0.002). Multivariable Cox regression analysis revealed that the signature was an independent prognostic factor for patients with bladder urothelial carcinoma (BLCA). A comparison of tumour node metastasis (TNM) stage and the signature indicated that the signature had better survival prediction power (AUC(signature)=0.79/0.64 vs. AUC(TNM)= 0.67/0. 60, Pl 0. 05). Functional analyses indicated that these prognostic genes from the signature may be involved in tumourigenesis-related biological processes and pathways. In conclusion, the multidimensional PCG-lncRNA-microRNA signature can be a novel prognostic marker to predict the survival of bladder cancer patients.

β-Blockers are a standard therapy for acute myocardial infarction (AMI) due to their better short-term and long-term outcomes. However, β-blockers are often under-prescribed in chronic obstructive pulmonary disease (COPD) patients with AMI, since they are thought be related to bronchospasm. The aim of this study was to investigate the association between the usage of β-blockers and the risk of mortality in COPD patients after first AMI via a nationwide, population-based cohort study. In this retrospective study, we identified 186,326 patients with AMI diagnosed between January 2000 and December 2012, 23,116 of whom had COPD, from the National Health Insurance Research Database. A total of 7609 patients (32.92%) were prescribed β-blockers, while 15,507 were not. The β-blocker patients were stratified into selective and non-selective β-blocker groups. Multivariate Cox proportional hazards models were used to estimate adjusted hazard ratios (HR) with 95% confidence intervals (95% CI). Selective β-blocker use showed a reduced risk of mortality, as compared with patients without β-blockers (HR 0.93; 95% CI 0.89–0.98; p

In vehicle networks, how to implement V2V (vehicle-to-vehicle) communications is always one hot issue, because of the structure which is similar to D2D communications proposed by cellular networks, we try to achieve an efficient V2V communication model through D2D techniques. In this paper, we propose a double-tiered D2D communication mode with the ratio coefficient of interference distance. The Tier-I of mode accomplishes the pairing among D2D terminals based on Voronoi diagram, and the Tier-II of mode achieves the shared channel selections as many as possible. According to the description of hypergraph geometry structure to the double-tiered D2D pairing algorithm, and the algorithm is split into two sub-problems, which refer to both bipartite graph and Voronoi diagram match under the constraint of SINR. According to the convergence of match between ratio factors introduced in the double-tiered mode, the double-tiered mode can be proved to be an optimal mode of channel reusing. Finally, we perform computer simulations to verify the performance based on the double-tiered D2D communication mode, and results indicate that the proposed mode possesses better performance compared with the spectrum sharing D2D communication mode.

Although the correlation between systemic infection and cardiovascular events has been identified, uncertainty still exists in the incidence and prognosis of sepsis in acute myocardial infarction (AMI). The purpose of our research was to evaluate the impact of sepsis on survival after first AMI.

Patient Initials or Identifier Number 16873191 ### Relevant Clinical History and Physical Exam The patient, a 63-year-old man, has type 2 DM and is a heavy cigarette smoker. He suffered from chest tightness when working with cleaning job. The characteristics of pain were retrosternal, sudden

Complex antagonistic interactions between Selenium (Se) and heavy metals have been reported in previous studies. However, little is known regarding the effects of Se on lead (Pb)-induced toxicity and the ion profile in the muscles of chickens. In this present study, we fed chickens either Se or Pb or both Se and Pb supplement and later analyzed the concentrations of 26 ions in chicken muscle tissues. We determined that a Se- and Pb-containing diets significantly affected microelements in chicken muscle. Treatment with Se increased the content of Se but resulted in a reduced concentration of Cu, As, Cd, Sn, Hg, and Ba. Treatment with Pb increased concentrations of Ni while reducing those of B, V, Cr, Fe, Co, Cu, Zn, and Mo. Moreover, Se also reduced the concentration of Pb, Zn, Co, Fe, V, and Cr, which in contrast were induced by Pb. Additionally, we also found that synergistic and antagonistic interactions existed between Se and Pb supplementation. Our findings suggested that Se can exert a negative effect on Pb in chicken muscle tissues and may be related to changes in ion profiles.

Patient initials or identifier number 4729117 ### Relevant clinical history and physical exam An 82 year-old male has multiple risk factors, including hypertension, diabetes mellitus, dyslipidemia and smoking. He also suffered from stage 5 chronic kidney disease. He suffered from chest

In the hybrid network of Device-to-Device (D2D) and cellular communications, reducing the co-channel interference is always hotpot problem, in which the interference involves either the co-channel among D2D terminals or between cellular and D2D links. Lower co-channel interference can improve the link spectrum efficiency effectively. This paper focus on discussing the D2D communications under the dedicated model, which is defined for no interference existing between cellular and D2D links. We depict a D2D-paring scheme to confront the influence of co-channel interference in D2D communications by introducing the Voronoi diagram. According to the location of D2D terminals, the Voronoi diagram can be constructed and rule the D2D-paring criterion that D2D terminals establish communications link only between adjacent polygons. The interference Management algorithm is proposed, which shows that small communications range causes lower co-channel interference, especially, when the channel inversion principle is considered. More intuitive result is obtained in the simulation part. Compared the D2D-paring scheme with some introduced classic literature, both the coverage probability and link spectrum efficiency can all be enhanced obviously.

Background Previous studies regarding the cardioprotective effects of dipeptidyl peptidase 4 (DPP-4) inhibitors have not provided sufficient evidence of a relationship between DPP-4 inhibition and actual cardiovascular outcomes. This study aimed to evaluate the impact of DPP-4 inhibitors on the survival of diabetic patients after first acute myocardial infarction (AMI). Methods This was a nationwide, propensity score-matched, case–control study of 186,112 first AMI patients, 72,924 of whom had diabetes. A propensity score, one-to-one matching technique was used to match 2672 controls to 2672 patients in the DPP-4 inhibitor group for analysis. Controls were matched based on gender, age, and a history of hypertension, dyslipidemia, diabetes, peripheral vascular disease, heart failure, cerebrovascular accident, end-stage renal disease, chronic obstructive pulmonary disease, and percutaneous coronary intervention. Results DPP-4 inhibitors improve the overall 3-year survival rate (log rank P

Type 2 diabetes are at a high risk of complications related to hypertension, and reports have indicated that insulin levels may be associated with blood pressure (BP). Fructose intake has recently been reported to promote insulin resistance and superoxide formation. The aim of this study is to investigate whether fructose intake can enhance superoxide generation and impair insulin signaling in the NTS and subsequently elevate BP in rats with fructose-induced hypertension. Treatment with fructose for 4 weeks increased the BP, serum fasting insulin, glucose, homeostatic model assessment-insulin resistance, and triglyceride levels and reduced the serum direct high-density lipoprotein level in the fructose group. The Tempol treatment recovered the fructose-induced decrease in nitric oxide production in the NTS. Immunoblotting and immunofluorescence analyses further showed that fructose increased the p38- and fructose-induced phosphorylation of insulin receptor substrate 1 (IRS1S307) and suppressed AktS473 and neuronal nitric oxide synthase phosphorylation. Similarly, fructose was able to impair insulin sensitivity and increase insulin levels in the NTS. Fructose intake also increased the production of superoxide in the NTS. The results of this study suggest that fructose might induce central insulin resistance and elevate BP by enhancing superoxide production and activating p38 phosphorylation in the NTS.

Previous evidence showed any radiation might carry a risk of skin or eye damage, malignant disease, or other hazards, which the U.S. radiation protection standards were also established based on this premise. However, most interventional cardiologists neglected the protection of radiation exposure