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Ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF6) as a new and environmentally friendly diluent was introduced to prepare poly(vinylidene fluoride) (PVDF) membranes via thermally induced phase separation (TIPS). Phase diagram of PVDF/[BMIM]PF6 was measured. The effects of polymer concentration and quenching temperature on the morphologies, properties, and performances of the PVDF membranes were investigated. When the polymer concentration was 15 wt%, the pure water flux of the fabricated membrane was up to nearly 2000 L·m−2·h−1, along with adequate mechanical strength. With the increasing of PVDF concentration and quenching temperature, mean pore size and water permeability of the membrane decreased. SEM results showed that PVDF membranes manufactured by ionic liquid (BMImPF6) presented spherulite structure. And the PVDF membranes were represented as β phase by XRD and FTIR characterization. It provides a new way to prepare PVDF membranes with piezoelectric properties.

A series of Pt/Cr1.3Fe0.7O3 catalysts were tested for CO oxidation, and the activities are improved by the presence of H2O. Such improvement is more significant on the single atom 0.2Pt/Cr1.3Fe0.7O3 than on the 2Pt/Cr1.3Fe0.7O3 containing Pt nanoparticles, with turnover frequencies of 0.396 and 0.094 s−1 at 60 °C under 1% CO + 1% O2 + 10% CO2 + 10% H2O, respectively. In-situ diffuse reflectance infrared Fourier transform spectroscopic study on these catalysts suggests that the promoting effect of H2O is due to the facile reaction between adsorbed CO and surface hydroxyl groups via H2O dissociation. Kinetic investigation reveals that the 0.2Pt/Cr1.3Fe0.7O3 gives a higher intrinsic rate constant than the 2Pt/Cr1.3Fe0.7O3 (9.23 × 10−5 versus 4.50 × 10−5 mol g−1 s−1 at 60 °C) for the formation of formate intermediate due to its weaker CO adsorption strength, which explains the more significant H2O promotion on the single atom Pt catalyst.

The d , d -dipeptidase enzyme VanX is the main cause of vancomycin resistance in gram-positive bacteria because of hydrolysis of the D-Ala-D-Ala dipeptide used in cell-wall biosynthesis. Continuous assay of VanX has proven challenging due to lack of a chromophoric substrate. Here, we report a direct approach for continuous assay of VanX in vitro and in vivo from hydrolysis of D-Ala-D-Ala, based on the heat-rate changes measured with isothermal titration calorimetry (ITC). With the ITC approach, determination of kinetic parameters of VanX hydrolyzing D-Ala-D-Ala and the inhibition constant of d -cysteine inhibitor yielded KM of 0.10 mM, kcat of 11.5 s−1, and Ki of 18.8 μM, which are consistent with the data from ninhydrin/Cd(II) assays. Cell-based ITC studies demonstrated that the VanX expressed in E. coli and in clinical strain VRE was inhibited by d -cysteine with IC50 values of 29.8 and 28.6 μM, respectively. Also, the total heat from D-Ala-D-Ala (4 mM) hydrolysis decreases strongly (in absolute value) from 1.26 mJ for VRE to 0.031 mJ for E. faecalis, which is consistent with the large MIC value of vancomycin of 512 μg/mL for VRE and the much smaller value of 4 μg/mL for E. faecalis. The ITC approach proposed here could be applied to screen and evaluate small molecule inhibitors of VanX or to identify drug resistant bacteria.

Pt catalysts supported on a series of CrxFe2-xO3 composite oxides with different Cr/Fe molar ratios were prepared and tested for CO oxidation. The Pt/Cr1.3Fe0.7O3 catalyst possesses the best performance (with a turnover frequency of ca. 0.2 s −1 at 80 °C under 1% CO + 1% O2 condition), due to its best reducibility which was related to the solid solution structure of the support. The catalyst also shows good stability in the presence of both 10% CO2 and 10% H2O. Detailed kinetic results and staged reaction indicate that CO2 and H2O play opposite roles in the reaction. The inhibiting role of CO2 is due to competitive adsorption of CO2 with CO and the formation of carbonate species. However, the addition of H2O could effectively decompose the carbonate and sustain the catalyst stability. Moreover, the promoting role of H2O could be mainly attributed to the weakened strength of CO adsorption and the fast interfacial reaction between CO and the surface hydroxyl groups formed via H2O dissociation, as revealed by the X-ray photoelectron spectroscopy, CO temperature-programmed desorption and the kinetic results.

Catalytic propane combustion was performed on a series of supported Pt/AlF3 catalysts. These catalysts are very active and stable in the reaction, and the 0.2Pt/AlF3 catalyst gives the highest specific reaction rate of 207.3 μmol gPt−1 s−1 at 220 °C. The 1Pt/AlF3 is much more active than the reference Pt/Al2O3 catalyst, due to its higher content of metallic Pt species than that in the Pt/Al2O3. Furthermore, turnover frequency (TOF) based on Pt dispersion increases with the surface concentration of metallic Pt0 in the catalyst, suggesting these species might be the active sites. Furthermore, synergistic roles of metallic and oxidized Pt species are found, as the TOFs calculated based on surface Pt0 concentration reaches a maximum at the Pt0/Pt2+ molar ratio of about 1. Such optimal Pt0/Pt2+ ratio implies the requirement of Pt0 Pt2+ pair in the reaction, probably due to the activation and cleavage of C H bond on metallic Pt atom and the sequential oxidation on the oxidized Pt atoms.

A series of C-AlF3 composite catalysts were prepared using a sol-gel method and different aluminum precursors (i.e. aluminum isopropoxide (Al(OiPr)3) and aluminum diacetate hydroxide (C4H7AlO5)). These catalysts were very active in gas-phase dehydrofluorination of 1, 1, 1, 3, 3-pentafluoropane. For example, a catalyst calcined at 400 °C with aluminum isopropoxide as the precursor (denoted as C-AlF3-AIP-400) gave a reaction rate of 8.30 μmol s−1 gcat-1 and a selectivity to 1, 3, 3, 3-tetrafluoropropene (HFO-1234ze) of above 99% at 340 °C. More importantly, the C-AlF3 catalysts showed excellent stability during 100 h reaction, while the pure AlF3 catalyst suffered severe deactivation owing to the coke deposition on the surface. In contrast, pre-deposited carbonaceous species formed in the catalyst due to the incomplete decomposition of organic precursors during the preparation procedure, which blocked strong acidic sites in the AlF3 and thus maintained the catalyst stability. Therefore, these findings provide useful information on the development of efficient catalyst for this reaction, particularly on the maintainance of catalyst stability.

Objectives The primary aim of this study was to determine if computed tomographic (CT) texture analysis measurements of the tumor are independently associated with progression-free survival (PFS) and overall survival (OS) in patients with unresectable pancreatic ductal adenocarcinoma (PDAC), including both unresectable locally advanced and metastatic PDAC, who were treated with chemotherapy. Methods After an institutional review board waiver was obtained, contrast material-enhanced CT studies in 41 patients with unresectable PDAC who underwent contrast-enhanced CT before chemotherapy between 2014 and 2017 were analyzed in terms of tumor texture, with quantification of mean gray-level intensity (Mean), entropy, mean of positive pixels (MPP), kurtosis, standard deviation (SD), and skewness for fine to coarse textures (spatial scaling factor (SSF) 0–6, respectively). The association between pretreatment and posttreatment texture parameters, as well as Δ value (difference between posttreatment and pretreatment texture parameters), and survival time was assessed by using Cox proportional hazards models and Kaplan-Meier analysis. Results Findings from the multivariate Cox model indicated that tumor size, tumor SD (HR, 0.942; 95% CI: 0.898, 0.988) and skewness (HR, 0.407; 95% CI: 0.172, 0.962) measurements with SSF = 3, and tumor SD (HR, 0.958; 95% CI: 0.92, 0.997) measurements with SSF = 4 were significantly and independently associated with PFS, while tumor size and tumor SD (HR, 0.928; 95% CI: 0.882, 0.976) measurements with SSF = 3 were significantly and independently associated with OS. None of the post-therapy texture parameters or Δ value had a significant association with OS or PFS in multivariate Cox regression models. Medium SD (SSF = 3) of more than 38.38 and coarse SD (SSF = 4) of more than 40.67 were associated with longer PFS after chemotherapy (for SSF = 3, median PFS was 10.0 vs 6.0 months [P = 0.024], and for SSF = 4, median PFS was 12.0 vs 6.0 months [P = 0.003]). SD of 38.38 or greater (SSF = 3) as a dichotomized variable was a significant positive prognostic factor for OS (median OS, 20.0 vs 9.0 months [P = 0.04]). Survival models that included a combination of pretreatment SD (SSF = 3) with tumor size, had the potential to perform better than SD alone, while having no statistical significance in this study (area under the ROC curve, 0.756 vs 0.715 [P = 0.066]). Conclusions Pretreatment CT quantitative imaging biomarkers from texture analysis are associated with PFS and OS in patients with unresectable PDAC who were treated with chemotherapy, and the combination of pretreatment texture parameters and tumor size have the potential to perform better in survival models than imaging biomarker alone.

The superbug infection caused by New Delhi metallo-β-lactamase (NDM-1) has grown into an emerging threat, labelling and inhibition of NDM-1 has proven challenging due to its shuttling between pathogenic bacteria. Here, we report a potent covalent scaffold, ebsulfur, for targeting the protein in vitro and in vivo. Enzymatic kinetic study indicated that eighteen ebsulfurs gained except 1a–b and 1f inhibited NDM-1, exhibiting an IC50 value ranging of 0.16–9 μM, and 1g was found to be the best, dose- and time-dependent inhibitor with an IC50 of 0.16 μM. Also, these ebsulfurs effectively restored the antibacterial activity of cefazolin against E. coli expressing NDM-1, and the best effect was observed to be from 1g, 1i and 1n, resulting in an 256-fold reduction in MIC of the antibiotic at a dose of 16 μg/mL. The equilibrium dialysis study implied that the ebsulfur disrupted the coordination of one Zn(II) ion at active site of NDM-1. Labelling of NDM-1 using a constructed fluorescent ebsulfur Ebs-R suggested that the inhibitor covalently bound to the target through SDS-PAGE analysis in vitro. Also, labelling NDM-1 in living E. coli cells with Ebs-R by confocal microscopic imaging showed the real-time distribution change process of intracellular recombinant protein NDM-1. Moreover, the cytotoxicity of these ebsulfurs against L929 mouse fibroblastic cells was tested, and their capability to restore antibacterial activity of antibiotic against clinical strains E. coli EC08 producing NDM-1 was determined. The ebsulfur scaffold proposed here is valuable for development of the covalent irreversible inhibitors of NDM-1, and also for labelling the target in vitro and in vivo.

Poly(vinylidene fluoride) (PVDF) membrane is widely used in water purification and wastewater treatment. In present paper, thermally induced phase separation (TIPS) was employed, and maleic acid dibutyl ester (DBM), a new diluent, was introduced for PVDF membrane preparation. Phase diagram and the effects of polymer concentration and quenching temperature on the structure, morphologies, properties, and performances of PVDF membranes were investigated. During the quenching process of PVDF/DBM system, liquid-liquid phase separation happened, and PVDF membranes with a bi-continuous structure were fabricated. What is interesting is that the liquid-liquid phase separation region was much wider than other PVDF/diluent systems. Thus, it is possible to fabricate PVDF membrane with a bi-continuous structure at high polymer concentrations, without stretching or additives. With the increase in polymer concentration and quenching temperature, mean pore size and pure water flux of the PVDF membrane decreased. Tensile stress of the prepared PVDF membranes reached to 6.18 MPa, because the wide liquid-liquid phase separation region induced a bi-continuous structure when the concentration of the PVDF membrane was at around 30%.

In order to improve the pharmacokinetic and pharmacodynamic properties of recombinant human interleukin-11 mutein (mIL-11) and to reduce the frequency of administration, we examined the feasibility of chemical modification of mIL-11 by methoxy polyethylene glycol succinimidyl carbonate (mPEG-SC). PEG-mIL-11 was prepared by a pH controlled amine specific method. Bioactivity of the protein was determined in a IL-11-dependent in vitro bioassay, its pharmacodynamic and pharmacokinetic properties were investigated by using normal and thrombocytopenic monkey models. N-terminus sequencing and peptide mapping analysis revealed that Lys33 is the PEGylated position for PEG-mIL-11. Bioactivity of PEG-mIL-11 assessed by B9-11 cell proliferation assay was comparable to that of mIL-11. More than 79-fold increase in area-under-the curve (AUC) and 26-fold increase in maximum plasma concentration (Cmax) was observed in pharmacokinetic analysis. Single dose administration of the PEG-mIL-11 induced blood platelets number increase and the effect duration were comparable to that of 7 to 10 consecutive daily administration of mIL-11 to the normal and thrombocytopenic monkey models. PEG-mIL-11 is a promising therapeutic for thrombocytopenia.

We aimed to demonstrate the tolerability and feasibility and the effect of remote ischemic post-conditioning on cognitive functioning in patients with post-stroke cognitive impairment.This was a single-center, randomized, outcome-blinded, placebo-controlled trial, randomized 1:1 to receive 4 cycles of remote ischemic post-conditioning or a sham procedure for 7 days. The primary outcome measure was tolerability and feasibility of remote ischemic post-conditioning. Secondary outcomes to measure the neurological function with national institute of health stroke scale and the cognitive impairment with Montreal Cognitive Assessment scale and Alzheimer's disease assessment scale-cognitive (at baseline, 90 days, 180 days).48 patients (24 RIPC and 24 Control) were recruited. remote ischemic post-conditioning was well tolerated with 90 out of 96 cycles completed in full. 4 patients experienced vascular events in the control group: 3 cerebrovascular and 1 cardiovascular event versus only 2 cerebrovascular events in the RIPC group. We showed the similar result in the neurological function with national institute of health stroke scale score with no statistically significant differences between RIPC and control group at baseline (P = 0.796) and 90 days (P = 0.401) and 180 days (P = 0.695). But compare with baseline, it was significantly difference in the control and RIPC group at 90 days (P 0.05) and 180 days (P 0.05). The comparison of Montreal Cognitive Assessment scale between two groups both showed that P 0.05 at baseline which was no statistical difference, but P 0.05 at 90 days and 180 days which were significant statistical difference. The comparison of Alzheimer's disease assessment scale-cognitive between two groups showed that P 0.05 at baseline (P = 0.955) and 90 days (P = 0.138) was no statistical difference, but P = 0.0050.05 at 180 days was significant statistical difference.The remote ischemic post-conditioning for post-stroke cognitive impairment was well tolerated, safe and feasible. The remote ischemic post-conditioning may improve neurological and cognitive outcomes in patients with post-stroke cognitive impairment. A larger trial is warranted. (Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: ChiCTR1800015231.).

In this article, the hydrogen masers in the NTSC (National Time Service Center) timekeeping laboratory are tested. In order to avoid the impact of larger noise of caesium atomic clocks, TA( k) or UTC( k) is not used as reference, instead, the four hydrogen masers are mutually referred and tested. The frequency stability of hydrogen masers is analyzed using the four-cornered hat method, and the Allan standard deviations of each single hydrogen maser in different sample times are estimated. Then, according to the characteristics of hydrogen masers, by removing the trend term, excluding outliers, and smoothing the data with a mathematical method to separate the Gaussian noises of hydrogen masers, and finally by through the Kolmogorov-Smirnov test, the Gaussian noise of each hydrogen maser is estimated.

Herein, we demonstrated the selective catalytic oxidation of diethylamine to N2 over MnOx/ZSM-5 catalysts. It was found that oxidation activity of diethylamine over MnOx/ZSM-5 catalysts increased when the loading of Mn increased, but the N2 selectivity decreased at 420 °C obviously. MnOx/ZSM-5(360) catalysts showed higher oxidation activity of diethylamine than MnOx/ZSM-5(18) catalysts with equivalent Mn loading, which was ascribed to the presence of MnOx species easily reduced and enriched on ZSM-5(360) support surface. However, MnOx/ZSM-5(18) catalysts containing moderate and strong surface acid centers in addition to the weak acid centers gave significantly higher N2 selectivity than MnOx/ZSM-5(360) catalysts possessing only weak surface acid centers. 20MnOx/ZSM-5(18) catalyst had relatively high oxidation activity of diethylamine and N2 selectivity, of which the lowest reaction temperature for diethylamine conversion at 98% (T98) is 240 °C and the N2 selectivity is exceeding 95.5% at 420 °C. Furthermore, 20MnOx/ZSM-5(18) catalyst showed wider temperature window (ΔT = 180 °C) with N2 selectivity over 95% than 20MnOx/ZSM-5(360) catalyst (ΔT = 80 °C). It can be concluded that the easily reduced and surface enriched MnOx species are favorable for the oxidation of diethylamine, the moderate and strong surface acid centers are beneficial to activation of diethylamine and the generation of N2.

The present study examined the interactive effects of organizational resources on classroom quality of 90 Chinese kindergartens using principal and teacher questionnaires and observational ratings of classroom practices. The results revealed that the average monthly teacher salary, child-teacher ratio and instructional management had significant direct associations with classroom quality, and the three-year average fiscal funding had a significantly positive association with instructional management and significant indirect association with classroom quality via the mediation of instructional management. The findings suggested that the allocation and organization of resources for teachers and instructional management in support of teachers and teaching are important for improving classroom quality, and that kindergarten leaders play a critical role in effectively transforming available resources into quality classroom practices.

Classically activated pro-inflammatory (M1) and alternatively activated anti-inflammatory (M2) macrophages populate the local microenvironment after spinal cord injury (SCI). The former type is neurotoxic while the latter has positive effects on neuroregeneration and is less toxic. In addition, while the M1 macrophage response is rapidly induced and sustained, M2 induction is transient. A promising strategy for the repair of SCI is to increase the fraction of M2 cells and prolong their residence time. This study investigated the effect of M2 macrophages induced from bone marrow-derived macrophages on the local microenvironment and their possible role in neuroprotection after SCI. M2 macrophages produced anti-inflammatory cytokines such as interleukin (IL)-10 and transforming growth factor β and infiltrated into the injured spinal cord, stimulated M2 and helper T (Th)2 cells, and produced high levels of IL-10 and -13 at the site of injury. M2 cell transfer decreased spinal cord lesion volume and resulted in increased myelination of axons and preservation of neurons. This was accompanied by significant locomotor improvement as revealed by Basso, Beattie and Bresnahan locomotor rating scale, grid walk and footprint analyses. These results indicate that M2 adoptive transfer has beneficial effects for the injured spinal cord, in which the increased number of M2 macrophages causes a shift in the immunological response from Th1- to Th2-dominated through the production of anti-inflammatory cytokines, which in turn induces the polarization of local microglia and/or macrophages to the M2 subtype, and creates a local microenvironment that is conducive to the rescue of residual myelin and neurons and preservation of neuronal function.

The synthesis of 2-chloro-3,3,3-trifluoropropene (HCFC-1233xf) from 1,1,2,3-tetrachloropropene was performed over a series of Y2O3-Cr2O3(F) catalysts and the effect of yttrium-doping on the performance of Cr2O3 catalysts was investigated. Various characterization results showed that the addition of yttrium in the Cr2O3 led to the formation of high valent Cr species in the samples, which could be consequently converted to catalytically active CrOxFy species during the pre-fluorination process. Although the Cr2O3 catalyst with or without yttrium-doping showed very high 1,1,2,3-tetrachloropropene conversion in long term reaction, the addition of yttrium in the Cr2O3 helped to maintain the high selectivity to HCFC-1233xf, with the highest selectivity (97%) obtained on a 1 mol% yttrium-doped Cr2O3 after 100 h reaction. X-ray photon spectroscopy results on the spent Cr2O3(F) and 1Y2O3-Cr2O3(F) catalysts indicated that the content of the active CrOxFy species declined after 70 h reaction, which was responsible for the loss of selectivity (from 97% to 88%), while it remained almost unchanged on the spent 1Y2O3-Cr2O3(F) catalyst.

A series of xMOy/Ce0.9M0.1−xO2−δ (M = Cu, Ni, Co, Fe) catalysts (Ce-M) were prepared by a sol–gel method and corresponding Ce0.9M0.1−xO2−δ catalysts (HCe-M) were obtained with an acid treatment. It was found that the Ce-M catalysts contained surface MOy species and Ce0.9M0.1−xO2−δ solid solution, as confirmed by the results of X-ray diffraction and Raman spectra, respectively. While the HCe-M catalysts only contained Ce0.9M0.1−xO2−δ solid solution. CO oxidation over these catalysts revealed that the activities followed an order of Ce-Cu > Ce-Ni > Ce-Co > Ce-Fe, but were remarkably higher than the corresponding HCe-M samples. The activities of the HCe-M catalysts were closely related to their reducibility originated from the oxygen vacancies in these samples. The most active HCe-Cu catalyst had the highest content of oxygen vacancies and thus was the most reducible. For the Ce-M catalysts, the enhanced catalytic performance was due to a synergy between the surface MOy species and the Ce-M-O solid solution, as the former provided sites for CO chemisorption and the latter promoted the activation of oxygen.