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Atomically dispersed oxide-on-metal inverse nanocatalysts provide a blueprint to amplify the strong oxide-metal interactions for heterocatalysis but remain a grand challenge in fabrication. Here we report a 2D inverse nanocatalyst, RuOx -on-Pd nanosheets, by in situ creating atomically dispersed RuOx /Pd interfaces densely on ultrathin Pd nanosheets via a one-pot synthesis. The product displays unexpected performance toward the oxygen reduction reaction (ORR) in alkaline medium, which represents 8.0- and 22.4-fold enhancement in mass activity compared to the state-of-the-art Pt/C and Pd/C catalysts, respectively, showcasing an excellent Pt-alternative cathode electrocatalyst for fuel cells and metal-air batteries. Density functional theory calculations validate that the RuOx /Pd interface can accumulate partial charge from the 2D Pd host and subtly change the adsorption configuration of O2 to facilitate the O-O bond cleavage. Meanwhile, the d-band center of Pd nanosubstrates is effectively downshifted, realizing weakened oxygen binding strength.

Background Several indices have been developed to predict survival of brain metastases (BM) based on prognostic factors. However, such models were designed for general brain metastases from different kinds of cancers, and prognostic factors vary between cancers and histological subtypes. Recently, studies have indicated that epidermal growth factor receptor (EGFR) mutation status may be a potential prognostic biological factor in BM from lung adenocarcinoma. Thus, we sought to define the role of EGFR mutation in prognoses and introduce a prognostic model specific for BM from lung adenocarcinoma. Methods Data of 256 patients with BM from lung adenocarcinoma identified with EGFR mutations were collected. Independent prognostic factors were confirmed using a Cox regression model. The new prognostic model was developed based on the results of multivariable analyses. The score of each factor was calculated by six-month survival. Prognostic groups were divided into low, medium, and high risk based on the total scores. The prediction ability of the new model was compared to the three existing models. Results EGFR mutation and Karnofsky performance status were independent prognostic factors and were thus integrated into the new prognostic model. The new model was superior to the three other scoring systems regarding the prediction of three, six, and 12-month survival by pairwise comparison of the area under the curve. Conclusion Our proposed prognostic model specific for BM from lung adenocarcinoma incorporating EGFR mutation status was valid in predicting patient survival. Further verification is warranted, with prospective testing using large sample sizes.

The present study aimed to determine the differences in gut microbiota between patients with chronic kidney disease (CKD) and healthy controls (HC) and search for better microbial biomarkers associated with CKD. The 16S rRNA gene sequencing approach was used to investigate the differences in gut microbiota between the CKD and HC groups. The study found that 12 phylotypes were overrepresented in the CKD group and 19 in the HC group at the genus level. Furthermore, genera Lachnospira and Ruminococcus_gnavus performed the best in differentiating between HC and CKD populations. In addition, this novel study found that the genera Holdemanella, Megamonas, Prevotella 2, Dielma, and Scardovia were associated with the progression of CKD and hemodialysis. In conclusion, the composition of gut microbiota was different in CKD populations compared with healthy populations, and Lachnospira and R._gnavus were better microbial biomarkers. In addition, five phylotypes, including Holdemanella, Megamonas, Prevotella2, Dielma, and Scardovia, served as an indicator of the progression of CKD and hemodialysis. However, large‐scale prospective studies should be performed to identify the reliability of the set of these phylotypes as biomarkers.

Cotton is an economically important crop that provides both natural fiber and by-products such as oil and protein. Its global gene expression could provide insight into the biological processes underlying growth and development, which involve suites of genes expressed with temporal and spatial control by regulatory networks. Generally, the goal for cotton breeding is improvement of the fiber; thus, most previous research has focused on identifying genes specific to the fiber. However, seeds may also play an important role in fiber development. In this study, we constructed and systematically analyzed 21 strand-specific RNA-Seq libraries for Gossypium hirsutum, covering different tissues, organs and development stages, from which approximately 970 million reads were generated to provide a global view of gene expression during cotton development. The organ (tissue)-specific gene expression patterns were investigated, providing further insight into the dynamic programming associated with developmental processes and a way to study the coordination of development between fiber cells and ovules. Series of transcription factors and seed-specific genes have been identified as candidate genes that could elucidate key mechanisms and regulatory networks in nutrient accumulation during ovule development and in fiber development. This study reports comprehensive transcriptome dynamics at various stages of cotton development and will serve as a valuable genome-wide transcriptome resource for initial gene discovery and functional characterization of genes in cotton.

Phase-change materials (PCMs) play an important role in thermal energy management in response to the demand for energy conservation with increasing concerns about environmental pollution. The selection of an optimal PCM is a difficult and critical task because of the immense number of different materials available that have different characteristics. To weigh the influencing factors for a PCM and provide a feasible method to select the best PCM, the VIKOR method was introduced in the field of PCM selection. On the basis of the characteristics of PCMs, an evaluation system of three levels and six different attributes was constructed and a pairwise comparison matrix was established after analysis of the attribute relationships. The relative weights determined by the matrix and the VIKOR method were used to sort out the attributes of alternative PCMs comprehensively. The results show that the method is effective and practical to select PCMs, and stearic acid was determined to be the optimal PCM among the candidates for low-temperature thermal energy storage.

A series of 2-(phenylamino)-4-(trifluoromethyl)-1,6-dihydropyrimidine derivatives were synthesized efficienly via the reaction of aryl aldehyde, ethyl 4,4,4-trifluoro-3-oxobutanoate and 1-phenylguanidine carbonate catalyzed by sulfamic acid under solvent-free conditions. This protocol has the advantages of mild condition, high yields and environmentally benign procedure.

Molecular docking and three-dimensional quantitative structure–activity relationships (3D-QSAR) were used to develop models to predict binding affinity of polybrominated diphenyl ether (PBDE) compounds to the human transthyretin (TTR). Based on the molecular conformations derived from the molecular docking, predictive comparative molecular similarity indices analysis (CoMSIA) models were developed. The results of CoMSIA models were as follows: leave-one-out (LOO) cross-validated squared coefficient q2 (LOO) = 0.827 (full model, for all 28 compounds); q2 (LOO) = 0.752 (split model, for 22 compounds in the training set); leave-many-out (LMO) cross-validated squared coefficient q2 (LMO, two groups) = 0.723 ± 0.100 (full model, for all 28 compounds); q2 (LMO, five groups) = 0.795 ± 0.030 (full model, for all 28 compounds); and the predictive squared correlation coefficient r2pred = 0.928 (for six compounds in the test set). The developed CoMSIA models can be used to infer the activities of compounds with similar structural characteristics. In addition, the interaction mechanism between hydroxylated polybrominated diphenyl ethers (HO-PBDEs) and the TTR was explored. Hydrogen bonding with amino acid residues Asp74, Ala29, and Asn27 may be an important determinant for HO-PBDEs binding to TTR. Among them, forming hydrogen bonds with amino acid residues Asp74 might exert a more important function. Environ. Toxicol. Chem. 2011;30:2431–2439. © 2011 SETAC

A series of novel fused tetracyclic benzo[4,5]imidazo[1,2-a]thiopyrano[3,4-d]pyrimidin-4(3H)-one derivatives were synthesized via the reaction of aryl aldehyde, 2H-thiopyran-3,5(4H,6H)-dione, and 1H-benzo[d]imidazol-2-amine in glacial acetic acid. This protocol features mild reaction conditions, high yields and short reaction time.

Molecular docking and three-dimensional quantitative structure–activity relationships (3D-QSAR) were used to develop models to predict estrogenicity of polybrominated diphenyl ethers (PBDEs), para-hydroxylated polybrominated diphenyl ethers (para-HO-PBDEs), and brominated bisphenol A compounds to the human estrogen receptor α (hERα). Based on the molecular conformations developed from the molecular docking, predictive comparative molecular similarity indices analysis (CoMSIA) models were developed. The results of CoMSIA modeling with region focusing included were: leave-one-out (LOO) cross-validated coefficient q2(LOO) = 0.722 (all 26 compounds), q2(LOO) = 0.633 (the training set, 20 compounds), q2(LMO, two groups) = 0.520 ± 0.155 (26 compounds), q2(LMO, five groups) = 0.665 ± 0.068 (26 compounds), predictive r2, r2pred = 0.686 (the test set, 6 compounds), and Q2EXT = 0.678. The 3D-QSAR can be used to infer the activities of compounds with similar structural characteristics. The interaction mechanism between compounds and the hERα was explored. Hydrogen bonding of the compound with Glu353 in the hERα is an important determinant of the estrogenic activity of para-HO-PBDEs and brominated bisphenol A. Environ. Toxicol. Chem. 2010;29:660–668. © 2009 SETAC

For predicting the molar diamagnetic susceptibilities of organic compounds, a variable molecular connectivity indexmχ' and its converse index mχ'' based on adjacency matrix of molecular graphs and the variable atomic valence connectivity index δi' were proposed. The optimal values of parameters x, a, and y included in definition of δi', mχ' and mχ'' can be found by an optimization method. When x2.9, a1.10, and y0.36, a good five-parameter model for the molar diamagnetic susceptibilities can be constructed from 0χ', 1χ', 2χ', 1χ'' and 2χ'' by using the best subset regression analysis method. The correlation coefficient r, standard error s, and average absolute deviation of the multilinear regression (MLR) model are 0.9930, 4.96 cgs, and 3.74 cgs, respectively, for the 721 organic compounds (training set). The cross-validation by using the leave-one-out method demonstrates that the MLR model is highly reliable from the point of view of statistics. The average absolute deviation of predicted values of the molar diamagnetic susceptibility of another 360 organic compounds (test set) is 4.37 cgs for the MLR model. The results show that the current method is more effective than literature methods for estimating the molar diamagnetic susceptibility of an organic compound. The MLR method can provide an acceptable model for the prediction of the molar diamagnetic susceptibilities of organic compounds.

A series of semihomogeneous cation-exchange membranes were prepared with binary blend systems, such as sulfonated phenolphthalein poly(ether ether ketone) (SPEEK-C)/sulfonated poly(phenylene sulfide) (SPPS), or ternary blend systems, such as phenolphthalein poly(ether ether ketone) (PEEK-C)/SPEEK-C/SPPS, by solution blending and phase inversion, in which PEEK-C and SPEEK-C acted as binders and SPPS powder acted as a polyelectrolyte. Compared with homogeneous and heterogeneous membranes, the prepared semihomogeneous membranes had good electrochemical properties and mechanical strength as well as good dimensional stability. The fundamental properties of the membranes, such as the ion-exchange capacity, water content, electrical resistance, transport number, diffusion coefficient of the electrolytes, and streaming potential, were largely dependent on both the loading of the SPPS resin and the sulfonation degree of PEEK-C. Through the adjustment of these two important parameters, a series of semihomogeneous membranes with the desired conductivity and selectivity and the proper water content for different industrial purposes, such as electrodialysis, diffusional dialysis, and proton exchange, were achieved. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1478–1485, 2004

A new type of mono-sheet bipolar membrane was produced from a porous polyethylene (PE) substrate using simultaneous irradiation grafting polymerization of acrylic acid (AA) on one side and chloromethylstyrene (CMS) on the other side. PE film with absorbent filter paper absorbing AA on one side and paper absorbing CMS on the other side was irradiated in the cobalt-60 gamma ray irradiation field, followed by quaternization with trimethylamine aqueous solution. AA and CMS were grafted on the substrate membrane simultaneously. The performance of the final membrane is significantly affected by the irradiation time. For short irradiation time, the prepared membrane behaves as a bipolar membrane; whereas for long irradiation time, the final membrane behaves as a charge mosaic membrane. Therefore, by controlling the conditions, a bipolar membrane with good current rectification can be prepared, across which the voltage drop is ∼2.0 V at the current density 800 A/m2 in 1.0 M NaOH. This preparation method is simple and can be applied both in laboratory and in industry. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 572–576, 2003

Novel heterogeneous cation-exchange membranes using poly (ether sulfone)(PES) as binder and sulfonated poly(phenylene sulfide) (SPPS) powder as polyelectrolyte were prepared by the solution casting-immersion method. Compared with a conventional route for heterogeneous membrane, the steps of milling resin into fine powders and the pressing at high temperature are avoided, and thus permits a simple technique for the preparation of such membrane. The effect of the particle size and loading of SPPS resin on the properties of the membranes such as ion-exchange capacity, water content, electrical resistance, transport number, diffusion coefficient of electrolytes, etc., have been studied. It is shown that the membrane fundamental properties are largely dependent on both the resin loading and the particle size of SPPS resin. By adjusting these two important parameters, one can obtain heterogeneous membrane with both good conductivity, selectivity, and proper water content for different industrial purposes such as electrodialysis, diffusional dialysis, etc. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 167–174, 2004

A series of 2-(phenylamino)-4-(trifluoromethyl)-1,6-dihydropyrimidine derivatives were synthesized efficienly via the reaction of aryl aldehyde, ethyl 4,4,4-trifluoro-3-oxobutanoate and 1-phenylguanidine carbonate catalyzed by sulfamic acid under solvent-free conditions. This protocol has the advantages of mild condition, high yields and environmentally benign procedure.

A series of novel fused tetracyclic benzo[4,5]imidazo[1,2-a]thiopyrano[3,4-d]pyrimidin-4(3H)-one derivatives were synthesized via the reaction of aryl aldehyde, 2H-thiopyran-3,5(4H,6H)-dione, and 1H-benzo[d]imidazol-2-amine in glacial acetic acid. This protocol features mild reaction conditions, high yields and short reaction time.