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The use of thin polybenzimidazole membranes in high-temperature polymer electrolyte membrane fuel cells is explored. Membranes in thickness of 10–40 μm are prepared, doped and characterized, including fuel cell test. High molecular weight polymers enable fabrication of membranes as thin as 10 μm with sufficient mechanical strength. The thin membranes, upon acid doping, exhibit comparable conductivity and hence decreased ohmic resistance. Membrane electrode assemblies with thin membranes down to 10 μm show slightly lower open-circuit voltages than that for reference 40 μm but all above 0.97 V. This is in good agreement with the hydrogen permeability measurements, which show a value around 10−12 mol cm−1 s−1 bar−1, corresponding to a crossover current density of −2. The acid transferred from the membrane to the catalyst layer seems constant, as the iR-free polarization plots are nearly the same for membranes of varied thicknesses. The acid remaining in the membrane after the break-in period is estimated, showing an acid inventory issue when thin membranes are used. This is verified by using the membranes of higher acid doping levels.

With the widespread use of highly active antiretroviral therapy (HARRT), the survival time of AIDS patients has been greatly extended. However, the incidence of lung cancer in HIV-infected patients is increasing and has become a major problem threatening the survival of AIDS patients. The aim of this study is to use Weighted Gene Co-expression Network Analysis (WGCNA) and differential gene analysis to find possible key genes involved in HIV-infected lung cancer. In this study, using lung tissue samples from five pairs of HIV-infected lung cancer patients, second-generation sequencing was performed and transcriptomic data were obtained. A total of 132 HIV-infected lung cancer-related genes were screened out by WGCNA and differential gene expression analysis methods. Based on gene annotation analysis, these genes were mainly enriched in mitosis-related functions and pathways. In addition, in protein-protein interaction (PPI) analysis, a total of 39 hub genes were identified. Among them, five genes (ASPM, CDCA8, CENPF, CEP55, and PLK1) were present in both three hub gene lists (intersection gene, DEGs, and WCGNA module) suggesting that these five genes may become key genes involved in HIV-infected lung cancer.

Objective: Excessive lipid accumulation in adipocytes results in prevalence of obesity and metabolic syndrome. Curcumin (CUR), a naturally phenolic active ingredient, has been shown to have lipid-lowering effects. However, its underlying mechanisms have remained largely unknown. Therefore, the study aims to determine the effect of CUR on cellular lipid accumulation in porcine subcutaneous preadipocytes (PSPA) and to clarify novel mechanisms.Methods: The PSPA were cultured and treated with or without CUR. Both cell counting Kit-8 and lactate dehydrogenase release assays were used to examine cytotoxicity. Intracellular lipid contents were measured by oil-red-o staining extraction and triglyceride quantification. Apoptosis was determined by flow cytometry and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-nick end labelling assay. Adipogenic and apoptosis genes were analyzed by quantitative polymerase chain reaction and Western blot.Results: The CUR dose-dependently reduced the proliferation and lipid accumulation of PSPA. Noncytotoxic doses of CUR (10 to 20 μM) significantly inhibited extracellular signal-regulated kinase 1/2 (ERK1/2) phosphorylation and expression of adipogenic genes peroxisome proliferation-activity receptor-γ (PPAR-γ), CCAAT/enhancer binding protein-α, sterol regulatory element-binding protein-1c, adipocyte protein-2, glucose transporter-4 as well as key lipogenic enzymes fatty acid synthase and acetyl-CoA carboxylase, while ERK1/2 activation significantly reversed CUR-reduced lipid accumulation by increasing PPAR-γ. Furthermore, compared with differentiation induced media treated cells, higher dose of CUR (30 μM) significantly decreased the expression of AKT and B-cell lymphoma-2 (BCL2), while increased the expression of BCL-2-associated X (BAX) and the BAX/BCL-2 expression ratio, suggesting triggered apoptosis by inactivating AKT and increasing BAX/BCL-2 ratio and Caspase-3 expression. Moreover, AKT activation significantly rescued CUR inhibiting lipid accumulation via repressing apoptosis.Conclusion: These results demonstrate that CUR is capable of suppressing differentiation by inhibiting ERK1/2-PPAR-γ signaling pathway and triggering apoptosis via decreasing AKT and subsequently increasing BAX/BCL-2 ratio and Caspase-3, suggesting that CUR provides an important method for the reduction of porcine body fat, as well as the prevention and treatment of human obesity.

Background The purpose of this study was to investigate the risk factors of postoperative complications and reliable prognostic factors of long-term survival in HIV-infected patients with non-small cell lung cancer (NSCLC). Methods HIV-infected patients with NSCLC who underwent surgical treatment were retrospectively studied; a single-institutional analysis was conducted from November 2011 to August 2018. Pre- and postoperative clinical data, including age, gender, smoking history, highly active antiretroviral therapy (HAART), CD4+ T cell count, HIV viral load, cancer histology, clinical and pathological stage (p-stage), surgical result, Glasgow Prognostic Score (GPS), the Charlson comorbidity index (CCI), survival time and postoperative complications were collected. Results A total of 33 HIV-infected patients with NSCLC were enrolled of which 18 (54.7%) had preoperative comorbidities and postoperative complications were observed in 22 (66.7%) patients. Thirty-day mortality was not observed in these patients. Median survival time after surgery was 65 months: the MST of p-stage I patients was 65 months; p-stage II MST was unestimable; p-stage III MST was 21 months. Univariate analyses showed that postoperative complications were associated with HIV viral load (P = 0.002), CCI (P = 0.027), HAART (P = 0.028) and CD4+ T cell count (P = 0.045). However, multiple logistic regression analysis showed no correlation between HAART and postoperative complications. The p-stage was an independent prognostic factor for survival time. Conclusions In our single-arm retrospective analysis, the risk factors for postoperative complications in HIV-infected patients with NSCLC were HIV viral load, CCI and CD4+ T cell counts. The p-stage was a predictive factor for long-term survival.

Advanced ceramics, such as alumina and zirconia, are widely used in modern industries, due to their superior properties, such as high hardness and strength. Fracture toughness is a significant property that describes the capability of materials to resist crack instability and expansion to failure, and also helps when calculating the allowable working stress, and crack size, of the component. This paper comprehensively lists the current toughness-testing methods. With comparative investigations of various methods, edge chipping is found to be the simplest way of measuring the ceramic fracture-toughness, in terms of the dominant median crack, chip geometrical similarity, and force-distance relations, giving consideration to its potential application in industry. Moreover, to avoid the data variance from crack-length measurement in edge chipping, it is further proposed that the energy analyses can be used to improve the way in which the toughness expression is formulated.

Anion exchange membranes (AEM) are key components in anion exchange membrane water electrolysers. Recently developed materials are less susceptible to the alkaline degradation of the polymer backbone and quaternary ammonium groups. A remaining challenge is the mechanical stability in contact with hot water and dimensional stability when the temperature of the feed solution changes. One solution is to reinforce membranes with a porous support. Since support materials like PEEK or PTFE have a different swelling behavior than the matrix and no strong interactions with the matrix, voids can form, and gas crossover increases. In this work, we approach this issue by pore filling polybenzimidazole nanofiber mats with the bromomethylated precursor of mTPN, an ultra-stable AEM material. During drying, a covalent interaction between support (PBI amine groups) and matrix (-CH2Br) is established. After quaternization, the optimized PBI/mTPN-50.120 composite membrane still shows a high conductivity of 62 mS cm−1, but 37% reduced length swelling in comparison to the non-reinforced membrane. Tensile strength and Young modulus increase 17% and 56% to 49 MPa and 680 MPa, respectively. In an electrolyser, a stable voltage of 1.98V at 0.25 A cm−2 was achieved, and no change in membrane resistance was observed over the test time of 200 h (50 °C, 1 M KOH, catalysts based on Ni/Fe and Mo).

In recent years, the image segmentation method based on deep learning has achieved outstanding performance in the field of medical image, but there are still some issues which need to be solved. In semantic segmentation, corresponding category is classified for each pixel in the image, while the instance segmentation conducts detection and segmentation of target in area-of-interest. With the continuous development of deep learning, these two tasks are increasingly integrated to realize panoramic image segmentation. This paper proposes a panoramic image segmentation network. Firstly, the bisenet network architecture is integrated to the image segmentation branch; secondly, in the image detection branch, the mask-rcnn network architecture is employed for this network; thirdly, these two branches use the same backbone network for simultaneous training and mutual improvement. Finally, we apply the proposed method in both the street view database and LiTS medical database. The results of massive experiments show that our algorithm has great performance.

Background: Purpose of this study was to explore the influence of miR-4262 on the progression of acute myeloid leukemia (AML) and its molecular mechanism.Methods: Quantitative real-time polymerase chain reaction (qRT-PCR) was carried out to assess the expression of miR-4262 in AML serum and cell lines. MTT, Transwell assays and flow cytometry were adopted to investigate the effect of miR-4262 on cell proliferation, invasion, migration and apoptosis abilities of HL-60 cells respectively. Luciferase reporter assay was conducted to reveal the target relationship of miR-4262 and KLF6. Western blot analysis was utilized to evaluate the expression level of proteins.Results: Relative expression of miR-4262 was up-regulated in AML serum and cell lines (PmiR-4262 expression was closely related to FAB classification (P=0.002) of AML patients. miR-4262 mimics could promotes the proliferation, invasion and migration of HL-60 cells, while miR-4262 inhibitor is obviously weakened these biological behaviors. Luciferase assay illustrated that miR-4262 can directly interact with KLF6 3’UTR. Up-regulation of miR-4262 could decrease KLF6 level, and increase EGFR level, while the down-regulation of miR-4262 showed the opposite results. Moreover, KLF6 gene knockdown reversed the results caused by miR-4262 inhibitor (PKLF6 could significantly promoted the proliferation, invasion and migration of HL-60 cells which is caused by miR-4262 inhibitor.Conclusions: miR-4262 was obviously increased in AML serum and cells, it promotes the progression of AML by regulating KLF6.

Background: This research aimed to explore the genetic association of Toll-like receptor 2 (TLR2) gene polymorphisms with acute myelocytic leukemia (AML) susceptibility in Chinese population.Methods: Firstly, the genotypes of TLR2 polymorphism were detected in 148 AML patients and 126 healthy controls by polymerase chain reaction (PCR). The genotype distribution of every polymorphism in the control group was detected whether conformed to Hardy-Weinberg equilibrium (HWE). The genotype frequency difference of TLR2 polymorphism between the case and control groups was compared by chi-square test and odds ratio (OR) with 95% confidence interval (95%CI) was calculated to express the risk of AML resulted from genetic variant of TLR2.Results: For TLR2 rs3804099 polymorphism, the heterozygous genotype TC was detected the significantly lower frequency in AML patients than that in the controls (P=0.031), so was C allele (P=0.021), which showed that rs3804099 was associated with the decreased the risk of AML (OR=0.580, 95%CI=0.354-0.953; OR=0.641, 95%CI=0.438-0.938). Similarly, GG genotype and G allele of rs1898830 also showed the obviously association with the risk reduction of AML (GG vs. AA: OR=0.430, 95%CI=0.200-0.924, G vs. A: OR=0.644, 95%CI=0.451-0.919). However, no significant association was found in rs7656411 with AML.Conclusions: TLR2 rs3804099 and rs1898830 polymorphisms may be the protective factors for AML, but not rs7656411.

Background: Present study was to explore the association between gene polymorphisms in Fc gamma receptor IIa (FCGR2A) and Iib (FCGR2B) and factor VIII (FVIII) inhibitor development in patients with hemophili A (HA) in a Chinese Han population.Methods: FCGR2A (131H/R) and FCGR2B (232I/T) polymorphsims were genotyped using PCR and direct sequencing method in 108 HA patients, including 23 cases with inhibitors and 85 without inhibitors. Chi-square (c2) test was applied to compare the genotype and allele frequencies between two groups. Odds ratio (OR) and 95% confidence interval (95%CI) were calculated to indicate the relative susceptibility of HA.Results: FCGR2A 131RH genotype frequency had a significantly increased trend in inhibitor group compared with the non-inhibitor group, suggesting a momentous role of 131H/R polymorphism for inhibitor development in HA patients. Individuals carrying 131RH genotype showed higher risk to be attacked by the inhibitor development in HA patients (OR=4.929; 95%CI=1.029-23.605). However, there were no significant differences of FCGR2B (232I/T) polymorphism genotype and allele frequencies between inhibitor and non-inhibitor groups.Conclusion: FCGR2A (131H/R) was in relation to the susceptibility of FVIII inhibitors development in HA patients.

In the present study, we aimed to investigate the therapeutic mechanisms of carrot juice fermented with Lactobacillus rhamnosus GG (LGG) on type 2 diabetic mellitus (T2DM) based on the regulation of gut microbiota. Carrot juice fermented with LGG was enriched with free phenols, organic acids and short-chain fatty acids (SCFAs). Supplementation of carrot juice fermented with LGG (DFCL) could favorably regulate blood glucose, insulin, antioxidant capacity and morphology of the pancreas and kidney in the diabetic rats, accompanied by an increase of SCFAs in the cecum. Furthermore, high-throughput sequencing (HTS) analysis revealed that DFCL supplementation altered the composition of gut microbiota, showing increased relative abundances of functionally relevant enterotypes, such as Christensenellaceae_R-7_group, Oscillibacter, Ruminococcaceae_UCG-013, Lachnospiraceae_NK4A136_group and Akkermansia. In addition, Spearman's correlation analysis revealed that Desulfovibrio, Ruminococcaceae and Alloprevotella were closely correlated with biochemical biomarkers. Meanwhile, DFCL treatment regulated the expressions of genes involved in glucose metabolism at the mRNA and protein levels.

Modified atmosphere packaging (MAP) is widely adopted for meats and meat products. While an effective cold chain may provide microbial safety during storage, several key spoilers, active at these conditions, can still induce spoilage. Thus, the objective of this study was to evaluate the effects of MAP on spoilage indexes and bacterial population of predominant spoilers in fresh pork loins at super-chilling (−2 °C) storage for 28 d. The results showed a negligible color improvement in Group A after 14 d while reduced TVB-N (13.33 vs 16.58 mg N/100 g), TBARS (1.79 vs 2.28 MDA/kg), TVC (6.5 vs 7.2 log CFU/g), and psychrotrophic bacteria count (6.1 vs 6.8 log CFU/g) were found in Group B in comparison to control group (D) at the end of storage. The abundance of Pseudomonas spp., Brochothrix spp., lactic acid bacteria, and Photobacteria spp., regarded as predominant spoilers of meat, in general, was influenced by the gas composition used in the packages. Although the abundance of specific spoilers, such as Serratia liquefaciens and Carnobacterium divergens, were reduced in Group C, significant inhibitions of Pseudomonas spp., Brochothrix spp., Serratia spp., Hafnia spp., Acinetobacter spp., Kurthia spp., and Kocuria spp. Were detected in Group B packs over time. Nevertheless, Pseudomonas spp. And Brochothrix spp. Were the abundant spoilers detected among different groups, hence, it is necessary to elucidate their adaptive mechanisms in the cold chain. Further studies into their spoilage and adaptive mechanisms are needed in order to control their proliferation in meat during storage.

Chemoresistance is a critical obstacle to the treatment of hepatocellular carcinoma (HCC). The mechanisms underlying resistance to doxorubicin, cisplatin, and 5-fluorouracil involve p53 and P-glycoprotein (P-gp). p53 plays a role in cell growth; therefore, resistance mechanisms involve chemotherapy-induced apoptosis and p53 mutation and inactivation. P-gp is an energy-dependent drug efflux pump regulated by p53. Its role in drug resistance has provided new insights into the mechanisms underlying the involvement of p53 and P-gp in chemoresistance and may alter our traditional understanding of p53 and P-gp function. This review outlines the roles and principal mechanisms of p53 and P-gp mediated chemoresistance in HCC.

Summary Wheat (Triticum aestivum L.) incurs significant yield losses from powdery mildew, a major fungal disease caused by Blumeria graminis f. sp. tritici, (Bgt). ENHANCED DISEASE RESISTANCE1 (EDR1) plays a negative role in the defense response against powdery mildew in Arabidopsis thaliana; however, the edr1 mutant does not show constitutively activated defense responses. This makes EDR1 an ideal target for approaches using new genome-editing tools to improve powdery mildew resistance. We cloned TaEDR1 from hexaploid wheat and found high similarity among the three homoeologs of EDR1. Knock-down of TaEDR1 by virus-induced gene silencing (VIGS) or RNA interference (RNAi) enhanced resistance to powdery mildew, indicating that TaEDR1 negatively regulates powdery mildew resistance in wheat. We used CRISPR/Cas9 technology to generate Taedr1 wheat plants by simultaneous modification of the three homoeologs of wheat EDR1. No off-target mutations were detected in the Taedr1 mutant plants. The Taedr1 plants were resistant to powdery mildew and did not show mildew-induced cell death. Our study represents the successful generation of a potentially valuable trait using genome-editing technology in wheat and provides germplasm for disease resistance breeding. This article is protected by copyright. All rights reserved.

To study the effects of Pim-3 on lung adenocarcinoma A549 cells. A549 cells were divided into an untreated group (without any treatment), a scramble siRNA group (transfected with control siRNA), and a Pim-3-deficient group (transfected with Pim-3 siRNA).Pim-3-deficient cells are the experimental sample, whereas scramble siRNA and untreated cells are the corresponding negative controls. Western blotting was performed to detect the expression levels of Pim-3 protein, the phosphorylation of signal transducer and activator of transcription 3 (STAT3), and the expression levels of downstream target genes (p21, cyclin D1, Bcl-2, and Bax). Flow cytometry was performed to analyze cell cycle and apoptosis.In the Pim-3-deficient group, Pim-3 was downregulated, the STAT3 phosphorylation level decreased, the levels of cyclin D1 and Bcl-2 decreased, but the levels of p21 and Bax increased. Meanwhile, cell proliferation was significantly inhibited (The downregulation of Pim-3 was closely related to the activation status of the lung STAT3 signaling pathway, mediated cell proliferation inhibition and induced apoptosis.

Modified atmosphere packaging (MAP) is widely applied in packaging meat and meat products. While most studies had employed culture-dependent microbiological analyses or polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), the recent application of high-throughput sequencing (HTS) has been effective and reliable in detecting the microbial consortium associated with food spoilage. Since MAP application is limited in China, applying HTS in assessing the microbial consortium of meat and meat products in the country becomes imperative. In this study, quality indexes and bacterial enumeration often used as spoilage indicators were employed to assess MAP fresh pork under chilled (4 °C) storage for 21 d. The results indicated that 70%O2/30%CO2 (Group A) retained more redness (a*) content, while 70%N2/30%CO2 (Group B) markedly reduced spoilage indicators compared to the control group. Notably, high-throughput sequencing indicated that Group B and 20%O2/60%N2/20%CO2 (Group C) inhibited the growth of abundant spoilers, Pseudomonas spp. and Brochothrix spp. Thus, MAP (Group B and C) has promising potential in inhibiting predominant meat spoilers during chilled storage. This study provides valuable information to food industries on the potential application of MAP to control meat spoilage in Chinese markets.

N-doped graphene-wrapped carbon nanoparticles (NGCNPs) are in situ synthesized by a facile bottom-up method. The heat treatment boosts the conversion of N-containing species from the pyrollic N to graphitic N and pyridinic N, thus improving the electrocatalytic activity towards the oxygen reduction reaction (ORR). The physical characterization including X-ray photoelectron spectroscopy, Raman spectra, specific surface area and charge transfer resistance indicates that 600 °C is a pivotal temperature for remarkably improving the electrochemical activity for ORR in terms of onset potential, half-wave potential, electron transfer number and peroxide yields.

Dual-doped graphene is synthesized by a facile solvothermal method with the assistance of ionic liquids containing both N and X (X = B, P or S) atoms. All three types of co-doped graphene present excellent catalytic activity, demonstrating preferred four-electron selectivity and low peroxide yields toward oxygen reduction reaction in alkaline solution. Particularly, N, P-graphene exhibits superior catalytic activity to its counterparts in terms of half-wave potential (ΔE 1/2 = −70 mV relative to commercial Pt/C), methanol tolerance and long-term stability. This could be attributed to the unique porous nanostructure, change of charge density and high distortion of carbon structures originating from the combination of large electronegativity of N element and big covalent radius of P atoms.

Phosphorus (P)/sulfur (S) co-doped porous carbon derived from resorcinol and furaldehyde are synthesized through one-step sol-gel processing with the addition of phosphorus pentasulfide as P and S source followed with freeze-drying and pyrolysis in nitrogen. The P/S co-doping strategy facilitates the pore size widening both in micropore and mesopore regions, together with the positive effect on the degree of graphitization of porous carbon through elimination of amorphous carbon through the formation and evaporation of carbon disulfide. As an electrode for supercapacitor application, P/S co-doped porous carbon demonstrates 43.5% improvement on specific capacitance of the single electrode compared to pristine porous carbon in organic electrolyte at a current of 0.5 mA due to the P-induced pseudocapacitive reactions. As for electrocatalytic use, promoted electrocatalytic activity and high resistance to crossover effects of oxygen reduction reaction (ORR) in alkaline media are observed after the introduction of P and S into porous carbon. After air activation, the specific capacitance of the single electrode of sample PS-pC reaches up to 103.5 F g−1 and an improved oxygen reduction current density.

Background: The number of HIV-infected patients with non-small-cell lung cancer (NSCLC) undergoing surgical treatment has been increasing recently. However, the risk factors for postoperative complications and reliable predictive factors for long-term survival remain to be unclear. This study aimed to investigate the risk factors of postoperative complications, and reliable prognostic factors in HIV-infected patients with NSCLC. Methods: HIV-infected patients with NSCLC who underwent surgical treatment were retrospectively studied; a single-institutional analysis was conducted from November 2011 to August 2018. Preoperative and postoperative clinical data, including age, gender, smoking history, highly active antiretroviral therapy (HAART), CD4+ cell count, HIV viral load, cancer histology, clinical and pathological stage (P-Stage), surgical result, Glasgow Prognostic Score (GPS), Charlson Comorbidity Index (CCI), survival time and postoperative complications were collected. Results: A total of 33 HIV-infected patients with NSCLC, consisted of 27 men and 6 women, were enrolled. The median age was 56 years (range 30 to 77 years). Of the 33 patients, 18 (54.7%) had preoperative comorbidities; Postoperative complications were observed in 22 (66.7%) patients. Thirty-day mortality was not observed in these patients, median survival time after surgery was 65 months; the MST of P-Stage I patients was 65 months; P-Stage II was unestimable; P-Stage III 21 months; P-Stage I/II was 67 months. Univariate and multivariate analyses showed that HIV viral load (P= 0.009), CCI (P= 0.035) and CD4+ cell count (P=0.045) were associated with postoperative complications; P-Stage were independent prognostic factors for survival time. Conclusion: The risk factors for postoperative complications were HIV viral load, CCI and CD4+ cell count, and that P-stage was the predictive factor for long-term survival in our single-arm retrospective analysis. To strengthen the effective management of HIV-infected patients with NSCLC, the risk factors for postoperative complications and the predictive factor for long-term survival should be considered before surgery. Funding Statement: This research was supported by a grant from the Thirteen-Fifth Mega-Scientific Project on “prevention and treatment of AIDS, viral hepatitis and other infectious diseases” (grant no. 2017ZX10201301-003-002). Declaration of Interests: The authors declare no conflicts of interest. Ethics Approval Statement: This study was approved by the Shanghai public health clinical center's ethics committee (Approval No. [2018] Y038).

The development of efficient non-precious-metal electrocatalysts towards the hydrogen evolution reaction (HER), with superior activity and stability, remains a great challenge in the area of renewable energy. In this work, we demonstrated a facile, one-step protocol to synthesize ultrathin graphitic layer (GL)-encapsulated ultrafine ditungsten carbide (W2C) nanoparticles (W2C@GL) with sizes smaller than 10 nm, exhibiting a superior HER activity in acidic solution. An efficient W2C phase, along with an improved electron transfer process by GL wrapping, cooperatively leads to a small Tafel slope of 68 mV dec−1 and a large exchange current density of 0.24 mA cm−2 for W2C@GL, which exceeds the previous W2C materials by far. Over 91% of the current density is maintained after over 8 h of operation, which indicates a good stability of this hybrid catalyst. Thus, W2C@GL with these excellent properties has been among the best non-noble metal HER electrocatalyst reported to date.

The accurate solid solubility data are a key to the design of process and the selection of operating conditions for separating PBDEs from waste electric plastic by solvent. The solubility of DecaBDE in different system was determined by using the isothermal dissolved method, and the impact law of temperature and solvent composition on the solubility of DecaBDE were discussed, the experimental solubility data was correlated with Apelblat equation equation. The results showed that the solubility of DecaBDE was mainly affected by the temperature and the solvent composition, and that Apelblat equation was suitable to fit the experimental results, the deviation was very small.

Cobalt monoxide (CoO) nanoparticles (NPs) and mesoporous carbon (MC) with large specific surface area were combined as a novel nanocomposite (CoO/MC) using a hydrothermal method to reveal outstanding electrocatalytic activity in the oxygen reduction reaction (ORR). The addition of polyvinylpyrrolidone (PVP) as the surfactant during the hydrothermal process is beneficial for the high dispersion of CoO NPs on the surface of MC. Among the as-acquired products, the CoO/MC nanocomposite prepared with 1.5 g PVP as the surfactant (CoO/MC-1.5) exhibits much better catalytic activity for the ORR with a more positive onset potential, a highly efficient four-electron transfer pathway and a larger current density than the others. Furthermore, the CoO/MC-1.5 nanocomposite demonstrates outstanding durability based on current–time chronoamperometric tests, which significantly prevails over a commercial Pt/C catalyst. The eminent catalytic activities of the CoO/MC-1.5 nanocomposite should be a result of the synergistic effect of the highly dispersed CoO nanoparticles and the ordered mesostructures with large specific surface area, which are advantageous for increasing the exposure of the active sites and promoting fast transfer of the reactants and products.

Polyacrylonitrile (PAN)-based carbon nanofibers prepared by electrospinning were physically activated using carbon dioxide as the oxidizing agent. The activation procedure was performed at 800 °C for different periods of time ranging from 15 to 60 min. The activated materials have a hierarchical structure with two sets of pore systems in the micropore range centered at ∼0.8 nm and small mesopore range centered at ∼2.8 nm. The activation not only increased the specific surface area and pore volume to 1123 m2 g−1 and 0.64 cm3 g−1, respectively, but also resulted in the evident loss of doped N atoms. The pyridinic and graphitic nitrogen groups are dominant among various N functional groups in the activated samples. CACNF-60, prepared by activating the carbon nanofibers (CNFs) for 60 min, showed excellent electrocatalytic activity for the oxygen reduction reaction (ORR) as well as superior long-term stability and methanol tolerance compared to commercial Pt/C in alkaline media. The excellent electrocatalytic activity of the activated sample is mainly due to its high N content (6.9 at%), unique hierarchical micro-/mesoporosity, and large specific surface area.

The objective of this study is to understand the impairment of learning and memory in mouse after chronic nitrite exposure. The animal model of nitrite exposure in mouse was created with the daily intubation of nitrite in adult healthy male mice for 3 months. Furthermore, the mouse's learning and memory abilities were tested with Morris water maze, and the expression of Synaptophysin and γ-Synuclein was visualized with immunocytochemistry and Western blot. Our results showed that nitrite exposure significantly prolonged the escape latency period (ELP) and decreased the values of the frequency across platform (FAP) as well as the accumulative time in target quadrant (ATITQ) compared to control, in dose-dependent manner. In addition, after nitrite exposure, synaptophysin (SYN) positive buttons in the visual cortex was reduced, in contrast the increase of γ-synuclein positive cells. The results above were supported by Western blot as well. We conclude that nitrite exposure could lead to a decline in mice's learning and memory. The overexpression of γ-synuclein contributed to the synaptic loss, which is most likely the cause of learning and memory impairment. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1720-1730, 2016.

The production of efficient and low-cost electrocatalysts for the oxygen reduction reaction (ORR) is one of the key issues for the extensive commercialization of fuel cells. In this paper, we describe a facile one-pot hydrothermal synthesis route to in situ grow spinel NiFe2O4 nanoparticles onto the graphene nanosheets which were produced in advance by a scalable solvothermal reduction of chloromethane and metallic potassium. The resultant NiFe2O4/graphene nanohybrid exhibits superior electrocatalytic activity for the ORR to pure graphene nanosheets and unsupported NiFe2O4 nanoparticles, which mainly favours a desirable direct 4e− reaction pathway during the ORR process. Meanwhile, the NiFe2O4/graphene nanohybrid exhibits the outstanding long-term stability for the ORR, outperforming the commercial 20 wt% Pt/C based on the current–time chronoamperometric test. The excellent catalytic activity and stability of NiFe2O4/graphene nanohybrid are ascribed to the strong coupling and synergistic effect between NiFe2O4 nanoparticles and graphene nanosheets.

The lack of efficient electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) has been a fatal issue for the development of metal–air batteries in large-scale commercialization. In this paper, spinel CoFe2O4 (CFO) nanoparticles were successfully in situ grown onto rod-like ordered mesoporous carbon (RC) by a facile, scalable hydrothermal method, followed by annealing at different temperatures. The as-acquired CFO/RC nanohybrid pyrolyzed at 400 °C (CFO/RC-400) has a high specific surface area (150.3 m2 g−1) and two sets of uniform mesopore systems (3.38 and 19.1 nm), all of which are favorable for the improvement of the electrocatalytic activity. The hybridization of CFO nanoparticles and the RC matrix results in increased ORR and OER electrocatalytic activity of the CFO/RC nanohybrids, which is significantly superior to that of unsupported CFO nanoparticles and pure RC. CFO/RC-400 shows better catalytic activity for the ORR with a direct four-electron reaction pathway than those prepared at other temperatures in terms of the onset potential and limiting current density. Furthermore, the CFO/RC-400 nanohybrid exhibits outstanding durability for both the ORR and OER, and can outperform commercial Pt/C. The excellent bifunctional electrocatalytic activities of the CFO/RC nanohybrids are mainly owing to the hierarchical mesoporous structures of the nanohybrids and strong coupling between the CFO nanoparticles and the RC matrix.