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In this work a novel method is unfolded to modify carbon felts (CF) to substantially improve the performance of the electrodes for vanadium redox flow batteries (VRFBs). The carbon felt, a well-known electrode material for VRFB, is catalytically etched by cobalt oxide to form carbon nanorods on the surface of the fibers comprising the CF. Unlike conventional multistep processes to grow nano-structures on carbon felts, this method simply involves a thermal treatment of catalyst-loaded felt in air to produce well aligned nanorods on its fibers. The surface morphology is optimized by etching temperature, treatment time and catalyst type. The catalytically etched CF shows an improved surface wettability and an enlarged specific surface area about two times compared to pristine CF that lead to an improvement of kinetics towards vanadium redox reactions. When used as electrode in all-vanadium redox flow battery, the nanorod-structured CF shows around 35% higher charge/discharge rate capability at 150 mA cm −2 and 80% retained-capacity compared to 48% in case of un-etched CF as confirmed by a long run test with a hundred cycles of charge/discharge operation at 50 mA cm −2 . [ABSTRACT FROM AUTHOR]

Here, we introduce a layered hollow sphere (LHS) architecture of iridium-decorated carbon electrode. The electrode was prepared by coating of a solution composed of graphene oxide (GO), IrCl 3 , and polystyrene bead followed by subsequent pyrolysis. The morphology of the electrode was investigated according to the composition of solution, and the electrocatalytic properties were characterized. The usage of GO highly enhanced the electrochemical surface area of the electrode (by ∼6 times). The LHS electrode also showed outstanding electrocatalytic properties: a current density of 89.99 mA/cm 2 could be obtained at a potential of 1.6 V. [ABSTRACT FROM AUTHOR]

Optimizing synthesis parameters is crucial in fabricating an ideal cathode material; however, the design space is too vast to be fully explored using an Edisonian approach. Here, by clustering eleven domain-expert-derived-descriptors from literature, we use an inverse design surrogate model to build up the experimental parameters-property relationship. Without struggling with the trial-and-error method, the model enables design variables prediction that serves as an effective strategy for cathode retrosynthesis. More importantly, not only did we overcome the data scarcity problem, but the machine learning model has guided us to achieve cathode with high discharge capacity and Coulombic efficiency of 209.5 mAh/g and 86%, respectively. This work demonstrates an inverse design-to-device pipeline with unprecedented potential to accelerate the discovery of high-energy-density cathodes. [Display omitted] • Inverse-design surrogate model is employed for discharge capacity prediction of lithium-ion batteries cathode materials. • Statistical imputation technique is exploited to solve the missing values and inconsistency in training data. • The proposed method enables the realization of high discharge capacity of 209.5 mAh/g with 86% coulombic efficiency. • We identified eleven descriptors from literature and reverse-engineered the synthesis parameters with high accuracy. [ABSTRACT FROM AUTHOR]

Background The clinical and economic impact of vancomycin-resistant Enterococcus (VRE) colonization remains unclear. Little data are available on factors affecting hospitalization length of stay (LOS) and costs. This study aimed to estimate mortality, LOS, and hospitalization costs for VRE colonized patients compared with a matched hospital population. Methods We performed a retrospective propensity score matched cohort study comparing the outcomes of patients with VRE colonization with those of uncolonized subjects matched at the time they were admitted to the intensive care unit (ICU). Between January 2008 and December 2010, we obtained rectal swab cultures within 24 hours of ICU admission to detect VRE colonization. Results During the study period, 567 (7.2%) of the 7,703 patients were colonized with VRE. There were 199 VRE colonized patients compared with 199 uncolonized patients using the propensity score. VRE colonized patients when compared with uncolonized patients were likely to have a higher case fatality rate (24.6% vs 17.1%; OR, 2.35). Longer total admission days were observed in the VRE colonized patients (28.7 vs 21.4 days; multiplicative effect, 1.25; P = .004). VRE colonization is found to be a significant factor associated with increased ICU cost in the multivariable regression model ($6,065 vs $5,298; multiplicative effect, 1.22; P = .029). Multivariable analysis identified the factors affecting ICU cost as follows: VRE colonization (odds ratio [OR], 1.20; P = .038), ICU length of stay (OR, 1.93; P < .001), ICU type (OR, 1.51; P = .001), valvular heart disease (OR, 2.38; P = .27), hospitalization within 12 months (OR, 1.21; P = .037), and use of invasive devices (OR, 1.28; P = .017). Conclusion Compared with a matched hospital population, VRE colonization was associated with increased mortality, LOS, and costs. Strict infection control programs, including preemptive isolation for a high-risk group, should be helpful. [ABSTRACT FROM AUTHOR]

Abstract: Platinum nanoparticles (Pt NPs) were deposited on a layer-by-layer (LBL) assembled carbon nanotube (CNT) thin film via the spontaneous reduction of H2PtCl6 at the functional defect sites of the CNT surface. This nanostructure was characterized by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The modified electrode can be used for the nonenzymatic detection of cholesterol by chronoamperometry (CA) in neutral PBS. We also studied the optimal number of CNT layer for obtaining high sensitivity. The sensor with 24 bilayer of CNT shows very low detection limit and a wide linear range from 0.005mM to 10mM with a sensitivity of 8.7μAmM−1 cm−2. The result is attributed to the LBL assembled structure and more continuous intercalated pathways for electron transport in LBL assembled CNT film and the fact that the CNT film can provide a larger surface area for Pt NP loading. The sensor has good anti-interferent properties in the presence of glucose, ascorbic acid, and dopamine. [Copyright &y& Elsevier]

Summary: Objective: The purpose of this study was to evaluate clinical features and outcomes of bacteremia in patients with liver cirrhosis (LC) and determine whether underlying LC is an independent risk factor for mortality in a population of patients with different underlying diseases. Methods: From the database of nationwide surveillance studies for bacteremia, data regarding bacteremia in patients with LC were analyzed and compared with those in patients with other diseases. Results: A total of 195 patients with LC were compared with 1659 patients with other underlying diseases. As for the site of infection, intraabdominal infection was more frequent in the LC group (P < 0.001), while pneumonia, urinary tract bacteremia, and primary bacteremia were more prevalent in the other diseases group (all P < 0.05). Patients with LC were more likely to have Klebsiella pneumoniae bacteremia (20.1% vs. 14.3%, P = 0.018), but less likely to have coagulase-negative staphylococcal bacteremia (5.1% vs. 10.4%, P = 0.028). The 30-day mortality rate was significantly higher in the LC group compared to the other disease group (27.2% [53/195] vs. 20.3% [336/1659], P = 0.025). Multivariate analysis revealed underlying LC as a significant predictor for mortality (OR, 2.11; 95% CI, 1.43–3.13; P < 0.001), along with old age, nosocomial acquisition, pneumonia, severe sepsis, and a higher Pitt bacteremia score. Conclusions: The mortality rate of patients with LC was significantly higher than that of patients with other diseases when they developed bacteremia. Underlying LC was found to be one of the independent risk factors for mortality in patients with bacteremia. [ABSTRACT FROM AUTHOR]

Abstract: Polypyrrole (PPy)/carbon nanotube (CNT) composite electrodes are fabricated on ceramic fabrics for electrochemical capacitor applications. The CNTs are grown on the ceramic fabrics by the chemical vapor deposition (CVD) method and PPy is subsequently coated on them by chemical polymerization. The large surface area and high conductivity of the CNTs on the porous ceramic fabrics enhance their energy storage capacity. PPy provides not only additional capacitance as an active material, but also enhances the adhesion between the CNTs and ceramic fabrics. Furthermore, PPy acts as a conducting binder for connecting every individual CNT to increase the capacitance. The morphology of the PPy–CNTs on the ceramic fabrics is confirmed by SEM and TEM, and the electrochemical characteristics are investigated by cyclic voltammetry and galvanostatic charge–discharge tests. [Copyright &y& Elsevier]

Summary: Background: Many procedures have been proposed for the treatment of sacral sores, and bilobed flaps are widely used to reconstruct defects of the lower third of the nose. This retrospective study was conducted to evaluate our experiences of bilobed flaps based on parasacral perforators, for the treatment of sacral sores. Methods: Twelve patients, six males and six females, aged 21–74 years (mean age: 51.08 years), with a sacral sore were treated with a bilobed flap at our institution from February 2007 to November 2009. Sacral sores were treated by en bloc excision and defects were closed using a bilobed flap in each case. Flaps were designed using parasacral perforators after considering pocket locations. The average postoperative follow-up duration was 16 months. Results: Primary wound healing was achieved in all patients. Large defects left after excision were easily closed using bilobed flaps, which provided tensionless wound closure. The postoperative courses were uneventful in all 12 cases, and no patient experienced recurrence. Conclusion: The use of a perforator-based bilobed flap enables regional reconstruction using well-vascularised tissues, and provides satisfactory and aesthetic results in sore patients. Furthermore, rerotation is possible in the event of sore recurrence. Accordingly, we consider the perforator-based bilobed flap to be a useful and additional tool for the treatment of pressure sores. [ABSTRACT FROM AUTHOR]

Summary: Background: The aim of this study was to identify risk factors for development of severe sepsis or septic shock and to evaluate the clinical impact of severe sepsis on outcome in patients with gram-negative bacteremia (GNB). Methods: From the database of a nationwide surveillance for bacteremia, patients with GNB were analyzed. Data of patients with severe sepsis or septic shock were compared with those of patient with sepsis. Results: Of 2286 patients with GNB, 506 (22.1%) fulfilled the criteria of severe sepsis or septic shock. Factors associated with severe sepsis or septic shock in the multivariate analysis included renal disease, indwelling urinary catheter, hematologic malignancy, and neutropenia. The 30-day mortality of patients with severe sepsis or septic shock was significantly higher than that of patients with sepsis (39.5% [172/435] vs. 7.4% [86/1170]; P < 0.001). Multivariable analysis revealed that solid tumor, liver disease, pulmonary disease, pneumonia, and pathogens other than Escherichia coli, which were risk factors of development of severe sepsis or septic shock, were also found to be strong predictors of mortality. Severe sepsis or septic shock was a significant factor associated with mortality (OR, 3.34; 95% CI, 2.35–4.74), after adjustment for other variables predicting poor prognosis. Conclusions: Severe sepsis or septic shock was a common finding in patients with GNB, predicting a higher mortality rate. Renal disease and indwelling urinary catheter were the most important risk factors significantly associated with severe sepsis or septic shock among patients with GNB. [ABSTRACT FROM AUTHOR]

Abstract: The permeabilities of He, H2, N2, O2, CO2, CH4, C2H6, C3H8, and n-C4H10 in poly[1-phenyl-2-[p-(trimethylsilyl)phenyl]acetylene] (PTMSDPA) and poly[diphenylacetylene] (PDPA) are presented and compared to those of poly(1-trimethylsilyl-1-propyne) (PTMSP), poly(1-phenyl-1-propyne) (PPP), and polysulfone. Like PTMSP, PTMSDPA, a disubstituted glassy acetylene-based polymer, exhibits higher permeabilities to organic vapors than to permanent gases due to its rigid polyacetylene backbone and bulky side groups, which provide a relatively high fractional free volume (FFV) value of 0.26. Desilylation was performed on PTMSDPA. The resulting material, PDPA, is totally insoluble in common organic solvents, so it has much higher chemical resistance than PTMSDPA. Additionally, due to its insolubility in polymerization solvents, desilylation provides the only known route to high molar mass PDPA. The FFV of the resulting membrane (PDPA) is reduced by approximately 12% relative to that of PTMSDPA. This leads to a decrease in gas permeability values and selectivity of organic vapors relative to nitrogen. For example, the oxygen permeability is reduced from 1200 to 500 Barrers upon desilylation. The pure gas selectivities decrease from 9 to 3 for n-C4H10/N2 and from 26 to 9 for C3H8/N2. [Copyright &y& Elsevier]

The density functional theory (DFT) has been used to simultaneously investigate physi-/chemi-sorption properties of hydrogen on the (10,0) single-walled carbon nanotube (SWCNT) walls. Physisorption of H2 outside the CNT with a vertical orientation to the tube axis above the center of a hexagon surface is the most stable state of physisorption and its binding energy is very weak, -0.792 kcal/mol. In the chemisorption of two hydrogen atoms the most stable state is above two adjacent carbon atoms of a hexagon with a C–H bond length of 1.10 Å and one C–H bond energy of -45.761 kcal/mol. Based on these results, we have also investigated the transition state and the reaction pathway from physisorption to chemisorption of hydrogen on the CNT. The energy barrier of the reaction from physisorption to chemisorption is about 78.837 kcal/mol and the reaction is not spontaneous at 0 K. Through the calculations of the Gibbs free energy change from physisorption to chemisorption with temperatures, we learned that it is not easy for the reaction to occur, which is a major obstacle for the practical use of the CNT as a hydrogen storage medium. [Copyright &y& Elsevier]

To evaluate the therapeutic efficacy of ceftriaxone+vancomycin+rifampicin (CVR) in the treatment of pneumococcal meningitis caused by a multidrug-resistant strain, single-drug regimens (ceftriaxone 100 mg/kg, rifampicin 15 mg/kg, or vancomycin 20 mg/kg), double-drug regimens (ceftriaxone+vancomycin [CV] and ceftriaxone+rifampicin [CR]) and a triple-drug combination (CVR) with or without dexamethasone were compared in a rabbit meningitis model. Meningitis was induced by a highly penicillin-resistant (MIC 2 mg/l) and ceftriaxone-resistant (MIC 4 mg/l) pneumococcal strain. Final therapeutic efficacy was evaluated by the bacterial concentration at 24 h, and the bacterial killing rate was also evaluated. All combination regimens were superior to ceftriaxone or vancomycin single-drug regimens with regard to sterilisation of CSF and bacterial killing rate. Rifampicin was as effective as combination regimens. Regardless of dexamethasone, therapeutic efficacy of CVR and CR were superior to that of CV. CVR showed comparable therapeutic efficacy to CR. Data suggested that CVR would not have additional therapeutic benefit over CR during the initial 24 h of treatment. [Copyright &y& Elsevier]

By comparing the activation energy for nucleation of individual intermetallic compound (IMC), the IMC phase that forms first is predicted as the one with the smallest activation energy. This methodology has been successfully applied to observations of IMC phases that form during liquid soldering on Cu and Ni plates. [Copyright &y& Elsevier]