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Intermetallic Ti-45Al-8Nb-(W, B, Y) (at.%) and Ti-46Al-5Nb alloys are directionally solidified at a constant growth rate of 30 µm·s−1 using a Bridgman type apparatus. The quenched microstructures and lengths of different phase regions were observed and measured after various growing times of 0–30 min. Results show that the phase transformations in different phase regions are mainly depending on the high temperature microstructure and the supercooling degree during quenching process. After isothermal holding, the primary phase grows into the liquid phase, the dendrites change from equiaxed to columnar grains, and the length of the L+β phase region, L+β+α phase region and mushy zone varies, indicating that the entire directional solidification process can be described by a static equilibrium — nonequilibrium — dynamic equilibrium evolution process. In addition, the gap between the original growth interface and front interface shows that the actual crystal growth rate is not equal to the drawing velocity during directional solidification.

The chemical composition variation of the TiAl-4722 alloys was examined in a batch of the industrial scale master ingots, and in the corresponding castings prepared by conventional vacuum arc remelting (VAR) combined with induction skull melting (ISM) and investment casting processes. The content changes of major elements and interstitial elements were evaluated based on the chemical analysis at the top and bottom of the ingots and castings. Results show that the contents of C, N, H, Fe and Si have almost no change in the ingots and castings, suggesting that the chemical analysis on these elements can be based on the batch analysis. The O content keeps almost the same in different ingots, but exhibits relatively large differences in castings, which was probably influenced by the reaction between the shell mold and the molten alloy, and the spalling of face coat of the shell mold during casting. For the major elements of Al, Nb and Cr, the composition difference between the top and the bottom of the ingots is less than that of the castings. But for the O element, the trend is different, especially for the castings, suggesting that the investment casting is a homogenization process for Cr and Nb, but a differentiation process for O. The contents of major elements in castings fluctuate mainly in the same range as that in the ingots, indicating that the contents of the major elements are controllable during investment casting.

Abstract In order to make full use of the impact of internal and external factors on the performance of title catalyst for ethyl benzene oxidation, the key internal influencing factors on the catalytic performance were modulated by coordinating and grafting manganese porphyrin to mesoporous and macroporous chitosan, and the important external factors (i.e. oxidation reaction conditions) were optimized using Response Surface Methodology. Under the Response Surface Methodology optimized oxidation reaction conditions (176.56 °C, 0.59 MPa, and 0.25 mg amount of manganese porphyrin), the catalyst could be used at least five times. The ethyl benzene conversion, catalyst turnover numbers, and yields reached up to 51.2%, 4.37 × 106 and 36.4% in average, respectively. Compared with the other optimized oxidation reaction conditions, the corresponding values increased 17%, 26% and 53%. Relative to the manganese porphyrin, the catalytic performance and efficiency of the immobilized catalyst had notably increased.

Abstract Background Multiple studies have reported that mesenchymal stem cell (MSC) therapy has beneficial effects in experimental models of sepsis. However, this finding remains inconclusive. This study was performed to systematically determine the connection between MSC therapy and mortality in sepsis animal models by pooling and analyzing data from newly published studies. Methods A detailed search of related studies from 2009 to 2019 was conducted in four databases, including MEDLINE, EMBASE, Cochrane Library, and Web of Science. After browsing and filtering out articles that met the inclusion criteria for statistical analysis, the inverse variance method of the fixed effects model was used to calculate the pooled odds ratios (ORs) and their 95% confidence intervals (CIs). Results Twenty-nine animal studies, including 1266 animals, were identified. None of the studies was judged to have a low risk of bias. The meta-analysis demonstrated that MSC therapy was related to a significantly lower mortality rate (OR 0.29, 95% CI 0.22–0.38, P

Abstract Background To develop a machine learning model for predicting acute respiratory distress syndrome (ARDS) events through commonly available parameters, including baseline characteristics and clinical and laboratory parameters. Methods A secondary analysis of a multi-centre prospective observational cohort study from five hospitals in Beijing, China, was conducted from January 1, 2011, to August 31, 2014. A total of 296 patients at risk for developing ARDS admitted to medical intensive care units (ICUs) were included. We applied a random forest approach to identify the best set of predictors out of 42 variables measured on day 1 of admission. Results All patients were randomly divided into training (80%) and testing (20%) sets. Additionally, these patients were followed daily and assessed according to the Berlin definition. The model obtained an average area under the receiver operating characteristic (ROC) curve (AUC) of 0.82 and yielded a predictive accuracy of 83%. For the first time, four new biomarkers were included in the model: decreased minimum haematocrit, glucose, and sodium and increased minimum white blood cell (WBC) count. Conclusions This newly established machine learning-based model shows good predictive ability in Chinese patients with ARDS. External validation studies are necessary to confirm the generalisability of our approach across populations and treatment practices.

Abstract Background Despite significant progress in drug treatment, the prognosis of patients with advanced pulmonary arterial hypertension (PAH) remains extremely poor. Many preclinical studies have reported the efficacy of stem cell (SC) therapy for PAH; however, this approach remains controversial. The aim of this systematic review and meta-analysis is to assess the potential efficacy of SC therapy for PAH. Methods The Medline, EMBASE, Cochrane Library, and Web of Science databases were searched from inception to August 12, 2018. Preclinical studies that evaluated the use of SC therapy for PAH were included. The primary outcome was pulmonary haemodynamics, as assessed by measurement of the right ventricular systolic pressure (RVSP), mean pulmonary arterial pressure (mPAP), and/or mean right ventricle pressure (mRVP). The secondary outcomes included the weight ratio of the right ventricle to the left ventricle plus septum (RV/LV+S), the right ventricle to body weight ratio (RV/BW), the percentage of pulmonary arteriole area index (WA), and/or the percentage of medial wall thickness of the pulmonary arteriole (WT). The quality of outcomes was evaluated using the SYstematic Review Centre for Laboratory animal Experimentation (SYRCLE) bias risk tool. The inverse-variance method with random-effects modelling was used to calculate pooled weighted mean differences (WMDs) and 95% CIs. Statistical analysis was performed with STATA 14.0. Results Twenty-eight eligible articles (722 animals) were included. SC therapy reduced the pooled WMDs (95% CIs) of RVSP, mPAP, mRVP, RV/LV+S, RV/BW, WA, and WT for animals with PAH, with values of − 14.12 (− 14.63, − 13.61), − 11.86 (− 12.35, − 11.36), − 17.33 (− 18.10, − 16.56), − 0.10 (− 0.10, − 0.09), 0.23 (0.21, 0.24), − 13.66 (− 15.71, − 11.62), and − 7.96 (− 7.99, − 7.93), respectively. Conclusions SC therapy is effective for PAH in preclinical studies. These results may help to standardise preclinical animal studies and provide a theoretical basis for clinical trial design in the future. Systematic review registration PROSPERO (http://www.crd.york.ac.uk/PROSPERO).

Ranunculus japonicus is an important medicinal herb widely used in East Asia. In this study, we report the first complete chloroplast genome sequence of Ranunculus japonicus using next-generation sequencing technology. The chloroplast genome size of R. japonicus was 156,981 bp. A total of 129 genes were included, consisting 84 protein-coding genes, eight rRNA genes, and 37 tRNA genes. Thirteen protein-coding genes had intron (ycf3 gene, rps12 gene, rps12 gene, clpP gene contained two introns). A further phylogenomic analysis of Ranunculaceae, including 10 taxa, was conducted for assessing the placement of R. japonicus. It will provide valuable genetic information for this medicinally important species.

The first complete chloroplast genome of Aster ageratoides Turcz. var. scaberulus (Miq.) Ling. is reported in this study. The total chloroplast genome size of A. ageratoides var. scaberulus was 153,071 bp and comprised of a large single-copy region (LSC with 84,896 bp), a small single-copy region (SSC with 18,269 bp), and two inverted repeat regions (IR with 24,953 bp). A total of 122 genes were included in the genome, including 83 protein-coding genes, 8 rRNA genes, and 37 tRNA genes. Eleven protein-coding genes had intron (ycf3, clpP and rps12 gene contained two introns. Further phylogenomic analysis of Asteraceae, including 13 taxa, was conducted for the placement of A. ageratoides var. scaberulus.

As an important medicinal herb, no complete organelle molecular data has been reported for Tubocapsicum anomalum. In this study, the first complete chloroplast genome of Tubocapsicum anomalum Makino was sequenced and assembled. The genome is 155,802 bp in length and contained 124 encoded genes in total, including 75 protein-coding genes, 10 ribosomal RNA genes, and 39 transfer RNA genes. The phylogenomic analysis showed that Tubocapsicum anomalum was closely related to Withania somnifera according the current sampling extent.

How was the catalytic performance of the title catalyst influenced and enhanced by the Response Surface Methodology optimized-reaction conditions? Based on our experimental data, the effects of the Response Surface Methodology optimized reaction conditions on the catalytic performance were investigated in this paper. The experimental results show that, the micro alterations of various reaction parameter values resulted in the micro changes of cyclohexane conversion, further causing the positive and negative effects, and resulting in the synergy or the antagonism to cyclohexane conversion. The statistic study via Response Surface Methodology showed that, (1) the size order of the effects of the parameters on cyclohexane conversion was that, the quadratic terms > the mutual interaction terms ≈ the single variable terms; (2) compared to Traditional Optimization Method, Response Surface Methodology could more quickly offer the precise optimum values of reaction conditions. In the five recycle applications of the title catalyst, on average, the catalytic activity and the catalytic efficiency were respectively increased 50% and 25% than those obtained from the Traditional Optimization Method-optimized reaction conditions; (3) compared to the other similar catalysts reported in literatures, the present catalyst was a biomimetic catalyst with the highest Turnover Frequency value (6.5 × 105 h-1).

Abstract Background The ProCESS, ARISE, and ProMISe trials have failed to show that early goal-directed therapy (EGDT) reduces mortality in patients with severe sepsis and septic shock. Although lactate-guided therapy (LGT) has been shown to result in significantly lower mortality, its use remains controversial. Therefore, we performed a meta-analysis to evaluate EGDT vs. LGT or usual care (UC) in adult patients with severe sepsis and septic shock. Methods Relevant randomized controlled trials published from January 1, 2001 to March 30, 2017 were identified in PubMed, EMBASE, Web of Science, and the Cochrane Library. The primary outcome was mortality; secondary outcomes included red cell transfusions, dobutamine use, vasopressor infusion, and mechanical ventilation support within the first 6 h and Acute Physiology and Chronic Health Evaluation II (APACHE II) score. Results Sixteen studies enrolling 5968 patients with 2956 in EGDT, 2547 in UC, and 465 in LGT were included in this meta-analysis. Compared with UC, EGDT was associated with a lower mortality (10 trials; RR 0.85, 95% CI 0.74–0.97, P = 0.01), and this difference was more pronounced in the subgroup of UC patients with mortality > 30%. In addition, EGDT patients received more red cell transfusions, dobutamine, and vasopressor infusions within the first 6 h. Compared with LGT, EGDT was associated with higher mortality (6 trials; RR 1.42, 95% CI 1.19–1.70, P = 0.0001) with no heterogeneity (P = 0.727, I 2 = 0%). Conclusion EGDT seems to reduce mortality in adult patients with severe sepsis and septic shock, and the benefit may primarily be attributed to red cell transfusions, dobutamine administration, and vasopressor infusions within the first 6 h. However, LGT may result in a greater mortality benefit than EGDT.

To investigate the effect of three-dimension (3D) thermal convection on columnar-to-equiaxed transition (CET), the CET transition during the solidification of an Al-Cu alloy was simulated by 3D cellular automaton model coupled with the fi nite element method (CAFE). The thermal convection in the liquid phase was considered. The results show that the thermal convection in the liquid phase promotes the CET. When the convection is present, the temperature gradient at the start position of CET increases and the growth velocity of columnar dendrite decreases. The convection infl uences the formation of elongated equiaxed grain through changing the local temperature gradient and dendritic growth velocity.

Abstract Background Tubular biomarkers have been regarded as emerging and promising markers for early diagnosis of diabetic kidney disease (DKD). The study was to determine the diagnostic capabilities of tubular biomarkers (urinary neutrophil gelatinase-associated lipocalin [NGAL], clusterin, and cystatin C) for DKD and diabetic microalbuminuria, and whether or not the tubular biomarkers appear earlier than microalbuminuria. Methods In this consecutive cohort study, 146 type 2 diabetes mellitus (T2DM) patients with a disease duration of ≥6 years were enrolled. Thirty age- and gender-matched subjects without any systemic diseases were recruited as the control group. Urinary samples collected before treatment were tested for NGAL, clusterin, and cystatin C. Results The levels of biomarkers were higher in patients with DKD (p

To understand the salt tolerance of different Brassica juncea germplasm resources, this study used Na-Cl solutions with concentrations of 0, 150 mmol/L, 200 mmol/L, and 250 mmol/L to treat 479 B. juncea germplasm resources from different countries under salt stress, and measured germination rate, root length, bud length, and fresh weight; Comprehensive evaluation of the salt tolerance of the test materials was conducted using principal component analysis, membership function, multiple linear regression analysis, and cluster analysis. The results showed that under the treatment of 200 mmol/L NaCl solution, 479 materials could be effectively classified into 4 categories: (1) 12 salt tolerant varieties; (2) 75 moderate salt tolerant varieties; (3) 313 salt tolerant varieties; and (4) 79 salt sensitive varieties. A multiple linear regression equation was established for the identification of salt tolerance in B. juncea, y= 0.537x1+0.310x2+0.089x3+0.064x4. The selected salt tolerant materials lay the foundation for cultivating new salt tolerant B. juncea. [ABSTRACT FROM AUTHOR]

Phenazines are secondary metabolites with broad spectrum antibiotic activity and thus show high potential in biological control of pathogens. In this study, we identified phenazine biosynthesis (phz) genes in two genome-completed plant pathogenic bacteria Pseudomonas syringae pv. tomato (Pst) DC3000 and Xanthomonas oryzae pv. oryzae (Xoo) PXO99A. Unlike the phz genes in typical phenazine-producing pseudomonads, phz homologs in Pst DC3000 and Xoo PXO99A consisted of phzC/D/E/F/G and phzC/E1/E2/F/G, respectively, and the both were not organized into an operon. Detection experiments demonstrated that phenazine-1-carboxylic acid (PCA) of Pst DC3000 accumulated to 13.4 μg L−1, while that of Xoo PXO99A was almost undetectable. Moreover, Pst DC3000 was resistant to 1 mg mL−1 PCA, while Xoo PXO99A was sensitive to 50 μg mL−1 PCA. Furthermore, mutation of phzF blocked the PCA production and significantly reduced the pathogenicity of Pst DC3000 in tomato, while the complementary strains restored these phenotypes. These results revealed that Pst DC3000 produces low level of and is resistant to phenazines and thus is unable to be biologically controlled by phenazines. Additionally, phz-mediated PCA production is required for full pathogenicity of Pst DC3000. To our knowledge, this is the first report of PCA production and its function in pathogenicity of a plant pathogenic P. syringae strain.

Hot corrosion behaviors of DZ466 alloy at 850℃ and 950℃ were investigated by using a NaCl/Na2SO4salt-deposit method. It is found that there are three corrosion layers on the alloy. The outer and the middle layers consist of(Ni,Co) O oxide and(Ni,Co) Cr2O4 with a spinel structure,respectively. The innermost layer is an inner corrosion layer,which consists of Ni3S2 at 850℃,and the internal oxidation Al2O3 can be produced close to the middle layer at 950℃. The same hot corrosion mechanism is shown at 850℃ and 950℃. The destruction of the oxidation film continuity is a key reason for hot corrosion of the alloy. The hot corrosion weight gain curves obey a parabolic law at the two temperatures,the rate constants are 3.1×10-11g2·cm-4·s-1 and 1.5 × 10-9g2·cm-4·s-1,and the hot corrosion activation energies are 179.2 and 138.3 kJ ·mol-1at 850℃ and 950℃,respectively.