Diammonium phosphate-modified ramie fiber reinforced polylactic acid composite and its performances on interfacial, thermal, and mechanical properties

In this study, the properties of molded ramie fibers reinforced with polylactic acid (PLA) biocomposites were investigated. Before preparation of composites, diammonium phosphate (DAP) was applied to the surface of ramie fibers with and without pretreatments to analyze the interfacial adhesion of ramie–PLA composite. Wettability and adhesion behavior of ramie fibers in the PLA resin were characterized by contact angle (CA) measurements. The surface chemical analysis was performed by Fourier transform infrared spectroscopy (FTIR). The thermal properties were recorded using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The wetting analysis results showed that the introduction of DAP treatment to ramie fibers significantly improved the wetting behavior of ramie in the PLA resin. Similarly, the results of TGA indicated that DAP treatment substantially decreased the degradation temperature of the composites. The result of FTIR was also consistent with the results of wettability, TGA, and DSC for the observed changes of peaks in the transmission spectrum

Preparatory mechanism of Ms8.0 Wenchuan earthquake evidenced by crust-deformation data

Some crustal-deformation data related to the Ms8.0 Wenchuan in 2008, was described and a model that is capable of explaining the observed deformation features is presented. The data include: pre-earthquake uplift in an area south of the epicenter obtained by repeated-leveling measurements; pre-earthquake horizontal deformation by GPS observation during two periods in Sichuan-Yunnan area; vertical deformation along a short cross-fault leveling line in the epicenter area; and co-seismic near-field vertical and horizontal crustal-movement data by GPS. The model is basically “elastic-rebound”, but involves a zone between two local faults that was squeezed out at the time of earthquake

Cerium-Doped CoMn₂O₄ Spinels as Highly Efficient Bifunctional Electrocatalysts for ORR/OER Reactions

Low-cost and highly efficient electrocatalysts for oxygen reactions are highly important for oxygen-related energy storage/conversion devices (e.g., solar fuels, fuel cells, and rechargeable metal-air batteries). In this work, a range of compositionally-tuned cerium-doped CoMn2O4 (Ce-CMO-X) spinels were prepared via oxidizing precipitation and subsequent crystallization method and evaluated as electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The Ce modification into the CMO spinels lead to the changes of surface electronic structure. And Ce-CMO-X catalysts display better electrochemical performance than that of pristine CMO spinel. Among them, Ce-CMO-18% shows the best activity. The Ce-CMO-18% processes a higher ratio of Co3+/Co2+, Mn4+/Mn3+, which is beneficial to ORR performance, while the higher content of oxygen vacancies in Ce-CMO-18% make for better OER performance. Thus, the Ce-doped CMO spinels are potential candidates as bifunctional electrocatalysts for both ORR and OER in alkaline environments. Then, the hybrid Ce-CMO-18%/MWCNTs catalyst was also synthesized, which shows further enhanced ORR and OER activities. It displays an ORR onset potential of 0.93 V and potential of 0.84 V at density of 3 mA cm−2 (at 1600 rpm), which is comparable to commercial Pt/C. The OER onset potential and potential at a current density 10 mA cm-2 are 183 mV and 341 mV. The superior electrical conductivity and oxygen functional groups at the surface of MWCNTs can facilitate the interaction between metal oxides and carbon, which promoted the OER and ORR performances significantly

Experimental studies and analyses on axial compressive properties of full iron tailings concrete columns

The structural properties of iron tailings must be verified for them to be used in reinforced concrete structures. In this study, finely ground iron tailings powder was used as an admixture, and iron tailings gravel and iron tailings sand were used as the coarse and fine aggregates, respectively, to prepare full iron tailings concrete (FITC), which was compared to conventional concrete (CC). Eight concrete column specimens comprising different raw materials were cast. Three slender and three short reinforced FITC columns were designed, tested under axial compression, and compared to the experimental results of the CC columns. The load-bearing and deformation capacities of FITC columns were investigated for the first time. The results indicated that the incorporation of iron tailings reduced the strength and modulus of elasticity of FITC by 7.1–8.8 % and 18.2–19.1 %, respectively. The bearing capacity of three FITC slender columns was 4.6–8.7 % less than that of the CC slender column, and the bearing capacity of three FITC short columns was 10.0–16.7 % less than that of the CC short column. The bearing capacity calculations of the FITC columns indicate that they are safe as per existing Chinese and ACI standards. However, their ductility and stiffness are inferior to those of CC columns. A calculation model for the axial compressive load capacity of FITC columns, which agreed with the test results, was selected

Several problems about strain calculation and analysis and correction of related deviation*

There exists many kinds of calculation models of plane and spherical strain fields, but the results of these models are different. The representative models was analyzed, and got some useful conclusions, in which some models are unbiased, some have deviations that can be corrected, some can only be used to compute strain in a uniform medium and can not be extended, and some can be used in the calculation and analysis of continuous strain field as well. Meanwhile, the correction relationship for spherical difference movement (displacement) computed from strain results was given, and the meaning of the non – differential term in spherical strain model was demonstrated

Effects of Rosuvastatin and Atorvastatin on Renal Function

Background: Several clinical trials have reported inconsistent findings for the effects of rosuvastatin (RSV) and atorvastatin (AN) on renal function. The aim of this meta-analysis was to investigate the effects of these 2 statins on glomerular filtration rate (GFR) and proteinuria respectively, and determine which is better. Methods and Results: PubMed, CENTRAL, Web of Knowledge, and ClinicalTrials.gov website were searched for randomized controlled trials. Eligible studies reported GFR and/or proteinuria during treatment with RSV or ATV compared with control (placebo, no statins, or usual care), or RSV compared with AN head to head. Trials that enrolled dialysis participants and teenagers were excluded. Statistical heterogeneity was assessed using the 12 statistic, and pooled results using the random-effects model. The standardized mean differences (SMD) and ratio of means (ROM) were measured, respectively, to analyze GFR and proteinuria. Sixteen trials with a total number of 24,278 participants were identified. Compared with control, changes in the SMD of GFR were 0.04 (95% confidence interval [CI]: 0.01-0.07) and 0.59 (95%CI: 0.12-1.06) for RSV and ATV, respectively. The ROMs of proteinuria were 0.59 (95%CI: 0.46-0.74) for RSV vs. the control group, and 1.23 (95%CI: 1.05-1.43) in the head-to-head comparison. Conclusions: Both RSV and ATV improve GFR, and ATV seems to be more effective in reducing proteinuria. The validity and clinical significance require high-quality intensive studies with composite clinic endpoints of kidney and death. (Circ J 2012; 76: 1259-1266)http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000303369800032&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Cardiac & Cardiovascular SystemsSCI(E)21ARTICLE51259-12667

Association between low serum magnesium level and major adverse cardiac events in patients treated with drug-eluting stents for acute myocardial infarction.

OBJECTIVES: We investigated the association of serum magnesium (Mg) levels and major adverse cardiac events (MACEs) after drug-eluting stent (DES) implantation. BACKGROUND: Mg depletion plays a key role in the pathphysiologic features of diabetes mellitus, hypertension, thrombosis, arrhythmias and coronary artery disease. Whether the depletion is related to the long-term prognosis of DES implantation is not known. METHODS: From 2008 to 2011, we enrolled 414 consecutive patients <50 years old who underwent DES implantation for acute coronary syndrome. Serum Mg level was analyzed and patients were followed up for a median of 24 months (interquartile range 14-32 months) for the occurrence of MACEs defined as death, myocardial infarction, stroke, and any revascularization. RESULTS: For patients with unstable angina, no significant association between serum Mg level and MACEs was found in the multivariate model. For patients with myocardial infarction, after adjusting for age, positive family history, smoking status, hypertension, hypercholesterolemia, and diabetes at baseline, the risk was 8.11-fold higher for patients with quartile 1 than 4 Mg level (95% confidence interval 1.7-38.75; P<0.01). In addition, when tested as a continuous variable, serum magnesium was a significant predictor for MACEs of acute myocardial infarction (HR [per 0.1 mM increase], 0.35 [95% CI, 0.19-0.63], p< 0.01), after adjustment for other confounders. CONCLUSIONS: Low serum level of Mg may be an important predictor of MACEs with DES implantation for acute myocardial infarction. Further research into the effectiveness of Mg supplementation for these patients is warranted

NLRP3 Gene Silencing Ameliorates Diabetic Cardiomyopathy in a Type 2 Diabetes Rat Model

<div><p>Background</p><p>Nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is associated with metabolic disorder and cell death, which are important triggers in diabetic cardiomyopathy (DCM). We aimed to explore whether NLRP3 inflammasome activation contributes to DCM and the mechanism involved.</p><p>Methods</p><p>Type 2 diabetic rat model was induced by high fat diet and low dose streptozotocin. The characteristics of type 2 DCM were evaluated by metabolic tests, echocardiography and histopathology. Gene silencing therapy was used to investigate the role of NLRP3 in the pathogenesis of DCM. High glucose treated H9c2 cardiomyocytes were used to determine the mechanism by which NLRP3 modulated the DCM. The cell death in vitro was detected by TUNEL and EthD-III staining. TXNIP-siRNA and pharmacological inhibitors of ROS and NF-kB were used to explore the mechanism of NLRP3 inflammasome activation.</p><p>Results</p><p>Diabetic rats showed severe metabolic disorder, cardiac inflammation, cell death, disorganized ultrastructure, fibrosis and excessive activation of NLRP3, apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), pro-caspase-1, activated caspase-1 and mature interleukin-1β (IL-1β). Evidence for pyroptosis was found <i>in vivo</i>, and the caspase-1 dependent pyroptosis was found <i>in vitro</i>. Silencing of NLRP3 <i>in vivo</i> did not attenuate systemic metabolic disturbances. However, NLRP3 gene silencing therapy ameliorated cardiac inflammation, pyroptosis, fibrosis and cardiac function. Silencing of NLRP3 in H9c2 cardiomyocytes suppressed pyroptosis under high glucose. ROS inhibition markedly decreased nuclear factor-kB (NF-kB) phosphorylation, thioredoxin interacting/inhibiting protein (TXNIP), NLRP3 inflammasome, and mature IL-1β in high glucose treated H9c2 cells. Inhibition of NF-kB reduced the activation of NLRP3 inflammasome. TXNIP-siRNA decreased the activation of caspase-1 and IL-1β.</p><p>Conclusion</p><p>NLRP3 inflammasome contributed to the development of DCM. NF-κB and TXNIP mediated the ROS-induced caspase-1 and IL-1β activation, which are the effectors of NLRP3 inflammasome. NLRP3 gene silencing may exert a protective effect on DCM.</p></div

First-Principles Study on Stability and HER Activity of Noble Metal Single Atoms on TiO₂: The Effect of Loading Density

The highly dispersed “single-atom (SA)” catalysts on oxide supports significantly alter the catalytic reaction activity and selectivity and meanwhile save the catalyst utilization. However, preparation of SA catalysts remains a challenge up to now. An approach effectively evaluating the stability and activity is required. Herein, density functional theory (DFT)-based first-principles calculations were performed to evaluate the stability and photocatalytic hydrogen evolution reaction (HER) activity of noble metal (NM = Ag, Au, Pd, and Pt) SAs loaded on TiO₂ support. The chemical potential-based thermodynamic model was employed to estimate the stability of SAs; the capability to trap photoelectrons on surface and free energy of hydrogen adsorption were used to estimate the photocatalytic HER activity of SAs. Compared to the (101) surface, the (001) surface is more feasible for preparation of NM SAs due to the “soft” structural character caused by incompletely saturated surface atoms. The stability of SAs on the (001) is getting better with the loading density lowering except for Au SA. After deposition of NM SAs on the (001), the photoelectron was extracted from the subsurface to the surface around the NM sites, facilitating the proton adsorption and reduction process. The calculated free energy of hydrogen adsorption shows that the photocatalytic HER activity of NM SAs on the (001) changes moderately with the loading density but is very different than those for the TiO₂ clean (001) and bulk NM (111). Both stability and activity evaluations dictate that Pd SA on the (001) is the most promising candidate catalyst for photocatalytic HER