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Electrochemical measurements, including cyclic voltammograms (CVs) and rotating ring disk electrode (RRDE) technique, are applied to determine the impact of surface functional groups on the electrocatalytic activity and H2O selectivity of multi-walled carbon nanotubes (MWCNTs) for the oxygen reduction reaction (ORR) both in acid and alkaline electrolytes. Here, three types of carbon nanotubes (CNTs) involving MWCNTs, MWCNTs-COOH (MWCNTs with carboxyl groups) and MWCNTs-OH (MWCNTs with hydroxyl groups) are investigated. Both CVs and RRDE results indicate that the order of ORR electrocatalytic activity and H2O selectivity is MWCNTs-COOH > MWCNTs-OH > MWCNTs in acid solution; while in alkaline medium, it is MWCNTs > MWCNTs-COOH > MWCNTs-OH. Furthermore, the ORR on these CNTs proceeds mainly through the two-electron reduction pathway followed by a gradual four-electron transfer reaction. Possible interpretation of the different ORR electrocatalytic activity and H2O selectivity in these two solutions is also discussed.

Triclosan (TCS) is an antibacterial chemical widely used in personal-care products and an endocrine disruptor. While TCS exposure is associated with insulin resistance and metabolic disorders in animals, few studies have assessed its effect on the risk of gestational diabetes mellitus (GDM) in humans. This study aimed to explore whether maternal urinary TCS level is associated with the risk of GDM and infant birthweight. We examined 620 pregnant women from Shanghai, China in 2012–2013. Urinary TCS level was measured with high-performance liquid chromatography–tandem mass spectrometry (HPLC–MS/MS), and categorized into high, medium and low in tertiles. GDM was defined based on recommendation of International Association of Diabetes and Pregnancy Study Groups (IADPSG). The GDM rate was 12.7%. TCS was detectable (≥0.1 ng/mL) in 97.9% women (median 2.7 ng/mL). There was a positive, but statistically non-significant association between urinary TCS levels and GDM (adjusted odds ratio 1.17; 95%CI: 0.99, 1.39, with each unit increase of log (TCS) ng/mL) with adjustment for urinary creatinine, maternal age, education, passive smoking, parity and prepregnancy BMI categories. 48.1% of infants were females. Birthweight was 122.8 g higher (95% CI: 13.9, 231.6 g) for female infants of women in high TCS (median 13.3 ng/mL) versus low TCS (median 0.77 ng/mL), with adjustment for urinary creatinine, prepregnancy BMI, GDM and other confounders. No association was found between maternal TCS and birthweight in male infants. These results suggested the potential for TCS to be associated with increased risk of GDM and a gender-specific association with higher birthweight among female infants in a population with widespread but moderate exposure to TCS., Graphical abstract Unlabelled Image, Highlights • Triclosan (TCS) was detectable (> 0.1 ng/mL) in 97.9% of Chinese pregnant women. • Maternal TCS exposure is associated with higher risk of gestational diabetes mellitus, which may partially intermediated via maternal BMI. • Maternal TCS exposure is associated with higher birthweight among female infants.

Hydrogen sulfide (H2S) is a critical biological messenger in numerous physiological and pathophysiological processes. Small-molecule fluorescent probes combined with fluorescent microscopy have been developed for the sensitive detection of H2S. Here, we designed and synthesized a long-wavelength BODIPY-based probe (TMSDNPOB) based on the thiolysis of dinitrophenyl ether according to photo-induced electron transfer theory and the results of computational calculation. 4,4-Difluoro-8-phenyl-1,5,7-trimethyl-3-(4-(2,4-dinitrophenoxy)styryl- 4-bora-3a,4a-diaza-s-indacene (TMSDNPOB) is nearly non-fluorescent, but the reaction product (TMSHOB) emits strong red fluorescence at 592 nm when excited at 574 nm. The long wavelengths of the designed probe indicate low background interference from biological matrix and little photo damage on fluorescence imaging of H2S. With the advantages of the turn-on probe for H2S including high sensitivity, high selectivity, good biocompatibility and low toxicity, the probe has been used for imaging H2S in living cells and liver tissues.

In the teaching of material engineering in high school, a comparison between a traditional technique and an advanced one not only can effectively promote the students to understand and grasp the new one, but also can be used as a useful tool to encourage the student to do more self-learning about material processing. In the present report, the students were taught to carry out the advanced electrospinning processes. The difficulties in clear explanations the complicated new process in the class could be easily overcome by the usage of traditional wet spinning as a start point. Based on their past knowledge and experience about the wet spinning processes, the college students majoring in material engineering quickly grasped the essences of electrospinning, discriminated the differences between electrospinning and wet spinning. Some students eagerly went to the experimental laboratory to carry out some experiments about the preparations and characterizations of electrospun polymeric nanofibers. A related start point for comparison is important to transfer knowledge about a new advanced material processing technique to the college students.

Fetal growth restriction (FGR) threatens perinatal health and is correlated with increased incidence of fetal original adult diseases. Most cases of FGR were idiopathic, which were supposed to be associated with placental abnormality. Decreased circulating placental growth factor (PGF) was recognized as an indication of placental deficiency in FGR. In this study, the epigenetic regulation of PGF in FGR placentas and the involvement of PGF in modulation of trophoblast activity were investigated. The expression level of PGF in placental tissues was determined by RT-qPCR, immunohistochemistry and ELISA. DNA methylation profile of PGF gene was analyzed by bisulfite sequencing. Trophoblastic cell lines were treated with ZM-306416, an inhibitor of PGF receptor FLT1, to observe the effect of PGF/FLT1 signaling on cell proliferation and migration. We demonstrated that PGF was downregulated in placentas from FGR pregnancies compared with normal controls. The villous expression of PGF was positively correlated with placental and fetal weight. The CpG island inside PGF promoter was hypomethylated without obvious difference in both normal and FGR placentas. However, the higher DNA methylation at another CpG island downstream exon 7 of PGF was demonstrated in FGR placentas. Additionally, we found FLT1 was expressed in trophoblast cells. Inhibition of PGF/FLT1 signaling by a selective inhibitor impaired trophoblast proliferation and migration. In conclusion, our data suggested that the PGF expression was dysregulated, and disrupted PGF/FLT1 signaling in trophoblast might contribute to placenta dysfunction in FGR. Thus, our results support the significant role of PGF in the pathogenesis of FGR.

The first example of ivy-like extended structure based on Ni mono-substituted Keggin polyoxomolybdate has been hydrothermally synthesized and characterized. The distorted organic bicapped Keggin POM modified by uncoordinated 4,4΄-bpys serves as an unprecedented synthon for the supramolecular assembly of 3-D frameworks through strong π⋯π stacking interactions. The compound could serve as a potential catalyst in the oxidation of styrene to benzaldehyde.

According to exist technical problems and requirements of the air-suction peanut precision mulching film and punching planter, the new air-suction peanut precision dibbler of the planter’ key working part was researched. It was introduced the composition and working principle of the dibbler. According to functional and technical requirements of the dibbler’ main parts, the structural design and analyze were done. The dibbler mainly consists of roller body, cavitations’ components, transmission system, and the air suction metering device. In the peanut growing typical region, field trial of the dibbler showed that overall performance is relatively stable, each component are operating smoothly, and the operating indicators can better meet the technical requirements.

Impact of carbon pre-treatment on the catalytic activity and selectivity of its own and its relevant non-precious metal Co-based catalyst (carbon-supported cobalt diethylenetriamine, CoDETA/C) for oxygen reduction reaction is investigated. Three pre-treatment methods involving thermal treatment, H 2 O 2 -oxidation and KOH-activation are used in this paper. Electrochemical activity demonstrated by cyclic voltammograms and rotating ring disk electrode technique in O 2 -saturated electrolyte shows that pre-treatment step has a significant effect on the catalytic activity and selectivity of carbon and its Co-based catalyst: (1) for carbon sample, a KOH-activation gives the highest activity in acid medium, while a H 2 O 2 -oxidation in alkaline solution; and (2) for its Co-based catalyst, the as-ground gives the highest activity and selectivity in acid solution, while a KOH-activation in alkaline medium. Raman spectra indicate that pre-treatment can decrease the disorder of carbon matrix. X-ray diffraction shows that face-centered cubic α-Co phases are present and pre-treatment of carbon can decrease the size of metal Co dispersed on the catalyst surface.

Distributed combined cooling, heating and power (CCHP) system shows great advantages and provides new development space for energy construction of rural areas in China. Economic benefits are the most important factors determining the further development of distributed CCHP system in rural area and the operation strategies make a great impact on its economic benefits. This paper establishes an analysis model for the operation strategies following the thermal loads (FTL) of NG distributed CCHP system driven by gas-steam combined cycle. The prime mover used in this investigation is a gas-steam combined cycle based on combined gas turbines and steam turbines. The model presented in this paper can be used to determine the operation strategies of CCHP system under different daily periods: peak periods, flat periods, and valley periods in different seasons.

Using diethylenetriamine ligand, a family of non-precious metal oxygen reduction catalyst is synthesized by pyrolysis of cobalt-diethylenetriamine chelate on carbon at elevated temperature from 600 to 900 °C. Cyclic voltammetry results show that pyrolysis temperature plays an important impact on improving catalytic activity and the maximum activity is obtained at 800 °C with its peak potential of 719 mV (SHE). For the best catalyst HT800, rotating-ring disk electrode measurement indicates that the number of electrons transferred is 3.80–3.85 at potential of 0.5 V with rotating rates from 100 to 1600 rpm and the catalyst loading of 648 μg cm −2 . XRD indicates that the cobalt-nitrogen chelate decomposes above 600 °C and nanometallic α-Co with different sizes is synthesized. Raman indicates that there are more defective sites on the carbon surfaces induced by N doping. Combined XPS data with electrochemical results, it indicates that a higher total N content does not lead to a higher ORR activity.

Electrochemical and X-ray absorption techniques are applied to determine the influence of pyrolysis and nitrogen-containing precursor loading on the catalytic activity and structure of carbon-supported cobalt triethylenetetramine (CoTETA/C) catalyst. These CoTETA/C catalysts with different nitrogen-containing precursor loadings are synthesized from pyrolyzing cobalt triethylenetetramine supported on carbon at 800°C in Ar atmosphere. For comparison, the as-prepared (without pyrolysis) is also studied. Cyclic voltammograms and rotating disk electrode measurements indicate that the as-prepared presents very low activity, while the CoTETA/C catalysts with different nitrogen-containing precursor loadings show good catalytic activity and the maximum is found for CoTETA/C catalyst with Co:TETA = 1:4. X-ray absorption measurements at Co and N K edges show that after pyrolysis the CoN4 centers are no longer detected along with little nitrogen atoms inserted into carbon matrix and nanometallic α-Co clusters are formed. X-ray diffraction also confirms the presence of nanometallic α-Co particles on the catalysts.

In this study, impact of pyrolyzing atmosphere on the catalytic activity and structure of non-precious metal Co-based catalysts for oxygen reduction reaction in acid and alkaline medium are investigated. These non-precious metal Co-based catalysts are prepared from pyrolyzing carbon-supported cobalt diethylenetriamine chelate (CoDETA/C) in Ar, N 2 and CO 2 atmosphere, respectively. X-ray diffraction indicates that metallic Co nanoparticles with different size are present on each catalyst. X-ray photoelectron spectroscopy shows that the Nat.% is CoDETA/C-Ar (1.54) > CoDETA/C-N 2 (1.39) > CoDETA/C-CO 2 (0.42), pyridinic- N and amino- N in CoDETA/C-N 2 is the highest among these three catalysts, while pyrrolic- N , graphitic- N and oxidized- N in CoDETA/C-Ar is higher than that in the other two catalysts. Electrochemical activity demonstrated by cyclic voltammograms and rotating ring disk electrode in O 2 -saturated acid and alkaline electrolyte shows that pyrolyzing atmosphere has an important effect on the catalytic activity and a maximum catalytic activity is obtained in N 2 atmosphere, followed by in Ar then CO 2 atmosphere, in terms of onset and half-wave potentials, ORR peak potential and current, limiting current, number of electrons transferred and H 2 O selectivity. The increase in catalytic activity may mainly attribute to the enhanced contents of pyridinic- N and amino- N .

The RNA-binding protein Musashi2 (Msi2) has been identified as a master regulator within a variety of stem cell populations via the regulation of translational gene expression. A recent study has suggested that Msi2 is strongly expressed in leukemic cells of acute myeloid leukemia patients, and elevated Msi2 is associated with poor prognosis. However, the potential role of Msi2 in leukemogenesis is still not well understood. Here, we investigated the effect of Msi2 knockdown on the biological properties of leukemic cells. High expression of Msi2 was found in K562 and KG-1a leukemic cell lines, and low expression was observed in the U937 cell line. We transduced K562 cells with two independent adenoviral shRNA vectors targeting Msi2 and confirmed knockdown of Msi2 at the mRNA and protein levels. Msi2 silencing inhibited cell growth and caused cell cycle arrest by increasing the expression of p21 and decreasing the expression of cyclin D1 and cdk2. In addition, knockdown of Msi2 promoted cellular apoptosis via the upregulation of Bax and downregulation of Bcl-2 expression. Furthermore, Msi2 knockdown resulted in the inactivation of the ERK/MAPK and p38/MAPK pathways, but no remarkable change in p-AKT was observed. These data provide evidence that Msi2 plays an important role in leukemogenesis involving the MAPK signaling pathway, which indicates that Msi2 may be a novel target for leukemia treatment.

A facile and rapid technique for the selective removal of metallic single-walled carbon nanotubes (M-SWCNTs) was developed by microwave-assisted treatment of SWCNTs with nitronium ions. Upon exposure to microwaves, M-SWCNTs homogeneously dispersed in organic solution were prone to react with an electron acceptor reagent, i.e., positively charged nitronium ions as compared to their counterpart, namely, semiconducting (S)-SWCNTs. The well-functionalized M-SWCNTs were separated and removed from residual S-SWCNTs by ultracentrifugation and filtration. The resulting material contained highly enriched S-SWCNTs, the proportion of which increased from approximately 62 mol% in as-received SWCNTs to nearly 90 mol%. The effectiveness in removing M-SWCNTs was confirmed by the resonant Raman spectra and UV-vis-NIR absorption spectra. The microwave-enhanced separation mechanism was discussed as well.

Intrahepatic cholestasis of pregnancy (ICP) is a pregnancy-specific disorder characterised by raised bile acids in foetal-maternal circulation, which threatens perinatal health. During the progression of ICP, the effect of oxidative stress is underscored. Peroxiredoxin-3 (PRDX3) is a mitochondrial antioxidant enzyme that is crucial to balance intracellular oxidative stress. However, the role of PRDX3 in placental trophoblast cells under ICP is not fully understood. We demonstrated that the level of PRDX3 was downregulated in ICP placentas as well as bile acids–treated trophoblast cells and villous explant in vitro. Toxic levels of bile acids and PRDX3 knockdown induced oxidative stress and mitochondrial dysfunction in trophoblast cells. Moreover, silencing of PRDX3 in trophoblast cell line HTR8/SVneo induced growth arrest and cellular senescence via activation of p38-mitogen-activated protein kinase (MAPK) and induction of p21WAF1/CIP and p16INK4A. Additionally, enhanced cellular senescence, determined by senescence-associated beta-galactosidase staining, was obviously attenuated by p38-MAPK inhibitor SB203580. Our data determined that exposure to bile acid decreased PRDX3 level in human trophoblasts. PRDX3 protected trophoblast cells against mitochondrial dysfunction and cellular senescence induced by oxidative stress. Our results suggest that decreased PRDX3 by excessive bile acids in trophoblasts plays a critical role in the pathogenesis and progression of ICP.

Purpose: The aim of this study is to contrast the coupling algorithm (CEE) and boundary heat exchange coefficients (Nu) used in treatment of the large blood vessel in thermal ablation. Methods: Based on the Pennes bioheat transfer equation, the models with blood vessel parallel to microwave antenna were built with finite element method. In two kind of simulation, blood flow rate was set in 0.2 m/s or boundary heat exchange coefficients was set in 1750 W / (m2 °C), respectively. Results and conclusions : There was no significant difference on shape of effective ablation areas and 54°C temperature contours by using two kinds of simulation methods, especially the place far away from the blood vessel. At the place near the blood vessel, the method of CEE is closer to real condition which considers directivity of blood. Whats more, there are higher temperature by using method of Nu inside effective ablation areas.

Continuous wave (CW) radar and global positioning system (GPS) is the main equipment of trajectory measurement in range. Based on range test background, propose a method to fuse GPS pseudo-range and CW radar range to provide complete trajectory positioning parameters, effectively reduce the impact of the systematic error of the measuring element to improve positioning precision of aircraft orbit solving. Through research on the measurement principle and the practice calculated data is given in this paper. Finally, several famous practical examples and simulation results are presented to illustrate our method efficiently.

China is experiencing a large scale of building construction, attracting great attention paid to debris generated by frequent construction and demolition activities for its cost inefficiency and environmental pollution. It is of great importance to better understand the magnitude and composition of the waste stream when developing rules, policies and strategies to manage this segment of the solid waste. In this study, after clarifying the definition of construction and demolition (C&D) waste according to its complex composition and diverse sources, approaches quantifying C&D waste to meet different requirements were summarized, and a simple weight-per-construction-area was employed to make an approximate estimation. Based on the main causes and status quo of C&D waste management, measures to reduce C&D waste were proposed to realize a sustainable construction industry, which include improving environmental awareness, strengthening the establishment of policy system and company waste management system, and reinforcing research and study work. This study also adds to the knowledge on research trend of C&D waste in China.

Sinter is the main raw material for ironmaking. It is very important to control sinter chemical composition and comprehensive performance. In this paper, a predictive system for sinter chemical composition FeO and the sinter yield was established based on BP neural network, which was trained by actual production data. The MATLAB m file editor was used to write code directly in this paper.The application results show that the prediction system has high accuracy rate, stability and reliability, the sintering productivity was improved effectively.

In this study, an analytical method using 1,3,5,7-tetramethyl-8-(N-hydroxysuccinimidyl butyric ester)-difluoroboradiaza- s -indacene (TMBB-Su) as the labeling reagent has been developed to simultaneously detect Se-methylselenocysteine (SeMeCys), selenomethionine (SeMet), S-methylcysteine (SMeCys) and methionine (Met) in green tea and gynostemma pentaphyllum infusion by high performance liquid chromatography (HPLC) coupled to fluorescence detection. The derivatization of four targeted amino acids proceeded with 80 μmol/L TMBB-Su in 10 mmol/L mixed acid buffer (pH 7.20) at 25 °C for 25 min, which was optimized by orthogonal array design. The baseline separation of these amino acid derivatives was obtained on a C 8 column with a binary gradient elution using the mobile phase of 20 mmol/L mixed acid buffer solution (pH 6.40) and methanol with 2.5% tetrahydrofuran (THF). Under the optimal derivatization and separation conditions, the detection limit of each targeted amino acid was achieved to 0.2 nmol/L. A good linear relationship in the range of 0.001–1 μmol/L was obtained with a regression coefficient higher than 0.9912 for each targeted amino acids, and the relative standard deviations (RSDs) ranged from 1.8% to 3.5% for within-day determination ( n = 6) and from 3.8% to 4.1% for between-day determination ( n = 6). The proposed method can be used to detect selenium- and sulfur-containing amino acids simultaneously, compared to the existing HPLC with element-specific detection methods. Recoveries within 94.4–108.3% from tea and gynostemma pentaphyllum samples indicated that the matrix effect could be negligible in sample analysis. SeMeCys, SeMet, SMeCys and Met were all found in selenium enriched green tea and gynostemma pentaphyllum infusion. SeMeCys was also detected in normal green tea infusion with a mean content of 0.98 μg/g.

Tiered pricing of household electricity is a new price measure using economic leverage to encourage energy conservation and emission reduction in electric power industry. Based on demand side response theory, the coal-saving optimization model of tiered pricing was established and the coal-saving effect under different structure of coal-fired units was studied. The results of case study indicate that the economic leverage role of tiered pricing will promote the clean energy power generation connecting to the grid effectively, and the coal-saving effect of tiered pricing in the areas with high comprehensive coal consumption rate of power generation will be more remarkable.

The sinter quality and the stability of composition could directly affect the yield, quality and energy consumption of ironmaking production. It is important for iron and steel industry to steadily control sinter chemical composition and analyze sintering energy consumption. The MATLAB m file editor was used to write code directly in this paper. A predictive system for two important sinter chemical composition (TFe and FeO), sinter output and sintering solid fuel consumption of was established based on BP neural network, which was trained by actual production data.) The application results show that the prediction system has high accuracy rate, stability and reliability, the sintering productivity was improved effectively.

For a long time, there is serious cross-subsidization among the power sales prices in China, and tiered pricing of household electricity is a new price measure for power consumption equity, resources utilization rationality and then achieving resources conservation and environmental protection. Based on demand side response theory, the optimization model of tiered pricing of household electricity with objective function of minimum household electricity consumption was built, and the coal-saving effect of tiered pricing was studied. The results of case study indicate that energy and coal saving effect of tiered pricing is remarkable.

a b s t r a c t In this study, a series of Fe-based non-noble metal and non-macrocycle catalysts, FeTETA/C, for oxygen reduction reaction (ORR) have been synthesized by pyrolyzing carbon-supported iron triethylenete- tramine chelate at various temperatures in an inert atmosphere. Electrochemical characterization revealed that heat treatment temperature plays an essential role on improving the catalytic property of the obtained catalysts for ORR, and the optimal could be achieved at 800 ◦ C with an ORR peak poten- tial of 0.751 V and an electron-transfer number of 3.85. Furthermore, the obtained optimal catalyst has excellent methanol-tolerance and acceptable acid-resistance. The effects of heat treatment tempera- ture on microstructure of the catalysts as well as the elemental state on the optimal catalyst surface have been investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM) and X-ray

Through analyzing the design methods of liquid sliding bearing and the matching spindle of common roller grinding head, the design methods and ideas of liquid sliding bearing and the matching spindle of high-speed roller grinding head are put forward, and on these bases, a kind of liquid sliding bearing and the matching spindle of high-speed roller grinding head are designed. By means of finite element analysis of the bearing and the matching spindle respectively, it can be known that thermal property of the designed liquid sliding bearing can meet the working demands of high-speed roller grinding, and the designed spindle can meet the demands of strength and stiffness under the condition of high-speed grinding, thus, important reference materials for forming core technologies of high-speed roller grinding head are provided.

To identify and analyze the genetic relationship of four species of Gentiana (G. macrophylla, G. straminea, G. dahurica and G. crassicaulis) recorded as Gentianae Macrophyllae Radix in the Chinese Pharmacopoeia, and two other Gentiana species (G. officinalis and G. siphonantha) often used as substitutes by ISSR, in order to estimate the reasonability of G. officinalis and G. siphonantha used as substitutes from the DNA level.Eight primers ivere screened to amplify all the samples and agarose gel electrophoresis were analyzed. NTSYSpc-2. 10E software was used to calculate similarity coefficient and draw dendrogram. Results: Nine characteristic bands were found in different species on the ISSR fingerprints and which could be used to identify five species except G. dahurica. The substitute G. officinalis firstly clustered with G. dahurica and G. siphonantha showed closer genetic relationship with G. straminea and G. dahurica. G. crassicaulis showed a far genetic relationship with the other five species.The dendrogram based on the ISSR data supports that G. officinalis and G. siphonantha can be used as substitutes of Gentianae Macrophyllae Radix.

The influence of 3d transition metal precursors has been studied to prepare non-precious metal catalysts (MTETA/C) for the oxygen reduction reaction (ORR) in acid electrolyte. All these 3d transition metal precursors are chelated with triethylenetetramine (TETA) and supported on BP 2000, then pyrolyzed at 800 � C in the presence of Ar. The catalysts are characterized in terms of structure and catalytic activity by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and electrochemical techniques. Variations of the electrocatalytic activity of these non-precious metal catalysts indicate that the metal precursors have obvious effects on the catalytic activity and this may be related to the N atoms and O species on the carbon surface indicated by XPS. Here, metal chloride is beneficial to prepare these catalysts for the ORR in acidic electrolyte. Furthermore, pyridinic N and pyrrolic N on the carbon surface facilitate the reduction of oxygen on these Fe-based and Co-based catalysts, respectively.

NAC transcription factors belong to a unique class of transcription factors in plants. The common characteristics of the NAC proteins are the presence of a conserved NAC domain, comprising of about 150 amino acids in N-terminals and a highly variable transcriptional regulation region in C-terminals. Extensive studies have revealed that NAC transcription factors not only play important roles in plant growth and development, but also have functions in regulation of responses to biotic and abiotic stresses. In this minireview, we summarized the functions and mechanisms of the NAC transcriptional factors in plant abiotic and biotic stress responses. We also discussed future directions towards understanding the biological functions of the members of the NAC transcriptional factors in plants.

a b s t r a c t A promising non-precious metal FeCoTETA/C catalyst has been easily synthesized, by chelating Fe and Co with triethylenetetramine (TETA) in ethanol followed by pyrolyzing in an Ar atmosphere, as electrocata- lyst for oxygen reduction reaction (ORR) in proton exchange membrane fuel cells (PEMFCs). The catalyst has been characterized with various physicochemical techniques as well as electrochemical analysis and single cell performance measurement. The results showed that nano-intermetallic FeCo particles and sev- eral types of N and O species are present on carbon matrix. The catalyst delivers better electrocatalytic activity toward ORR compared with CoTETA/C catalyst, the %H2O2 is about 10% with an electron-transfer number of around 3.8. The PEMFC with this catalyst in cathode reaches a maximum power density of 256 mW cm

Topsoil porosity (TSP) is an important parameter for the research of soil physics, agriculture and environmental protection. However, the traditional method for measuring porosity is time consuming. Conversely, a series of new methods measuring soil surface roughness (SSR) are increased and become more and more quickly. Some researchers propose to predict TSP by SSR. In this study, two fields cultivated by different tillage type were investigated under natural condition during four years (2006-2009). The results of this study show that (i) both of soil roughness and porosity are decreased over time; (ii) there are strong correlation between soil porosity and roughness effected by rainfall; (iii) after introduce the index of accumulative mean rainfall (AMR), a model of multiple linear regression for presenting the correlation among SSR, TSP and rainfall was built using sampling data of 2006-2009 with R2>0.7.

In order to develop a rapid and reliable method for B. cereus genotyping, factors influencing PFGE results, including preparation of bacterial cells embedded in agarose, lysis of embedded cells, enzymatic digestion of intact genomic DNA, and electrophoresis parameters allowing for reproducible and meaningful DNA fragment separation, were controlled. Optimal cellular growth (Luria-Bertani agar plates for 12-18 h) and lysis conditions (4 h incubation with 500 µg/mL lysozyme) produced sharp bands on the gel. Restriction enzyme NotI was chosen as the most suitable. Twenty-two isolates were analyzed by NotI digestion, using three electrophoretic parameters (EPs). The EP-a was optimal for distinguishing between isolates. The optimized protocol could be completed within 40 h which is a significant improvement over the previous methods.

The macroporous ceramic samples fabricated using the sponge replica and protein direct foaming methods were compared in terms of porosity, density, compressive strength and microstructure. The egg white protein was applied in both fabrication methods as the binder or foaming agent. The samples fabricated using the protein direct foaming method were stronger and more uniform pore structures in the similar porosity. This result was supported through the Weibull modulus analysis and the scanning electron microscope microstructure observation.

Modification of composites was a general method to improve their tribological behaviors. On the way to explore composites with enhanced tribological behaviors, we have successfully prepared hybrid PTFE/Nomex fabric/phenolic composite filled with multiwalled carbon nanotubes (MWCNTs) or MWCNTs modified by polystyrene (PS) with a grafting to method. The results of pin-on-disc type wear tests indicated tribological behaviors were improved both for hybrid PTFE/Nomex fabric/phenolic composite filled with MWCNTs and MWCNTs-PS, especially for that of filled with MWCNTs-PS. And the probable reason was also discussed based on the characterization results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Nucleophosmin (NPM1) gene mutations resulting in cytoplasmic delocalization of Nucleophosmin (NPMc+) are the most common genetic alteration in acute myeloid leukemia (AML). Here, we attempted to prepare monoclonal antibodies (mAbs) against NPM1 mutation A (NPM-mA) and investigated the mAbs' clinical utility in immunohistochemical detection of NPMc+AML. The pET-32a-NPM-mA vector with the whole open reading frame of the NPM-mA gene was constructed. E.coli BL21 transformed with the vector were induced to express the NPM-mA recombinant protein. BALB/c mice were immunized with the recombinant NPM-mA. Positive clones were selected by indirect ELISA and the mAbs were obtained. Immunohistochemistry was performed to detect the NPMc+ in bone marrow smears from 10 AML patients with NPM-mA. The results showed that the pET-32a-NPM-mA vector was successfully constructed and the NPM-mA recombinant protein was used to immunize the mice. Two positive clones (2G3 and 3F9) were selected. The mAbs against NPM-mA were raised, but did cross-react with wild type NPM1. The mAbs can be used to detect the cytoplasmic dislocation of NPM1 in all AMLs carrying NPM-mA. Our results show that anti-NPM-mA mAbs were produced. Though they would cross-react with wild type NPM1, the mAbs may still have potential in the detection of NPMc+AMLs.

Model for predicting wood density of Larch was established using near-infrared spectroscopy (NIR) combined with support vector machine (SVM). A hundred and seventeen Larch samples were used in the study. Wood density of samples was measured according to standard test methods for physical and mechanical properties of wood. Support vector machines for regression (SVR) was used for model building. Radial basis function (RBF) was used as kernel function to establish a model for predicting wood density. For the train set, the coefficient of determination (R2) and the mean square error (MSE) were 0.8504 and 0.6460×10-3, while the R2 and MSE was 0.8520 and 0.4451×10-3, respectively, for the test set. Results showed that using SVM in near-infrared spectroscopy calibration could significantly improve the model performance in order to rapidly and accurately predict wood density.

Nucleophosmin (NPM1) is an abundant and ubiquitously expressed phosphoprotein that is known to influence solid tumors progression. However, little is known about the role of NPM1 in leukemia. Here, we knocked down the NPM1 expression by RNA interference to investigate the role of NPM1 in leukemic cells proliferation and apoptosis. The interference vector pNPM1-shRNA was constructed and transfected into the human leukemic K562 cell line. The expression levels of NPM1 mRNA and protein were detected by quantitative real-time PCR and Western blot, respectively. Cells proliferation potential in vitro was assessed by methyl thiazolyl tetrazolium (MTT) and colony formation assays. Flow cytometry was used to detect the distribution of cell cycle. Cellular apoptosis was reflected by the relative activities of caspase-3 and caspase-8. The results showed that the expression levels of NPM1 mRNA and protein in K562 cells were significantly reduced after pNPM1-shRNA transfection. The cells growth was significantly inhibited in a time-dependent manner and the number of colonies was significantly reduced in the pNPM1-shRNA transfected cells. Meanwhile, the percentage of cells in G1 phase in the K562/pNPM1-shRNA cells was significantly increased. In addition, there were higher relative activities of caspase-3/8 in the pNPM1-shRNA transfected cells. These results indicate that down-regulation of NPM1 expression inhibits leukemic cells proliferation, blocks cell cycle progression and induces cellular apoptosis. It may implicate a potential target for leukemia gene therapy.

Hybrid polytetrafluoroethylene (PTFE)/Nomex (DuPont, USA) composite specimens were prepared with graphite and MoS2 as fillers. The friction and wear tests were conducted under dry sliding conditions at a speed of 0.26 m/s under various loads and environmental temperatures. The results showed that the incorporation of graphite was effective in reducing the wear of the hybrid PTFE/Nomex fabric composite, whereas the MoS2 filler was unfavorable for improving the wear resistance. X-ray photoelectron spectroscopy (XPS) results revealed that MoS2 was oxidized into MoO3 during sliding. The absence of the layered structure of MoO3 resulted in a higher wear rate of fabric composite. Differential scanning calorimetry (DSC) analysis of unfilled and graphite-filled composites and their debris indicated that graphite increased the thermal stability of the unfilled composite and therefore enhanced the wear resistance.

Gestational trophoblastic disease (GTD) includes frankly malignant choriocarcinoma (CCA) and placental site trophoblastic tumor and potentially malignant hydatidiform mole. p21-Activated kinase (PAK) 4 promotes cell motility. This study investigated the role of PAK4 in the pathogenesis of GTD. PAK4 messenger RNA and protein expressions in clinical samples and cell lines of normal placentas and GTD were determined by quantitative real-time polymerase chain reaction and western blot, respectively. The effects of human chorionic gonadotropin (hCG) and phosphoinositide 3 kinase (PI3K) on the expression and activation of PAK4 were investigated by treating CCA JEG3 and JAR cells with anti-hCG antibody and PI3K inhibitor, respectively. The effects of PAK4 on CCA cell proliferation, migration and invasion were assessed by corresponding functional assays. We demonstrated overexpression of PAK4 in GTD and CCA cell lines at both RNA and protein level. hCG is one of the upstream regulators of PAK4 expression, whereas activation of PAK4 is PI3K/PKB dependent in JEG3 and JAR cells. Significant correlation was found between PAK4 expression and proliferation index minichromosome maintenance complex component 7 (P = 0.007). In JEG3 and JAR cells, stably transfected PAK4 increased proliferation, migration and invasion, whereas small interfering RNA knockdown of PAK4 decreased proliferation, migration and invasion along with downregulated CDK6 and membrane-type 1 matrix metalloproteinase (MT1-MMP) and upregulated p16. We further found PAK4-mediated transcription of MT1-MMP in CCA cells by luciferase reporter assay. Our results demonstrated for the first time that overexpressed PAK4 was involved in the pathogenesis of GTD, promoting proliferation and enhancing cell migration and invasion in CCA cells.

An improved fabrication technique for conventional hot-pressed membrane electrode assemblies (MEAs) with carbon supported cobalt triethylenetetramine (CoTETA/C) as the cathode catalyst is investigated. The V – I results of PEM single cell tests show that addition of glycol to the cathode catalyst ink leads to significantly higher electrochemical performance and power density than the single cell prepared by the traditional method. SEM analysis shows that the MEAs prepared by the conventional hot-pressed method have cracks between the cathode catalyst layer and Nafion membrane, and the contact problem between cathode catalyst layer and Nafion membrane is greatly suppressed by addition of glycol to the cathode catalyst ink. Current density–voltage curve and impedance studies illuminate that the MEAs prepared by adding glycol to the cathode catalyst ink have a higher electrochemical surface area, lower cell ohmic resistance, and lower charge transfer resistance. The effects of CoTETA/C loading, Nafion content, and Pt loading are also studied. By optimizing the preparation parameters of the MEA, the as-fabricated cell with a Pt loading of 0.15 mg cm −2 delivers a maximum power density of 181.1 mW cm −2 , and a power density of 126.2 mW cm −2 at a voltage of 0.4 V.

Nucleophosmin (NPM1) plays key roles in ribosome biogenesis, centrosome duplication, and maintenance of genomic integrity. NPM1 mutations have been recently identified as the most frequent genetic alteration in acute myeloid leukemia and are related to leukemogenesis. NPM1 mutations are involved in the regulation of cell proliferation, cell cycle, and apoptosis. However, the oncogenic potential of NPM1 mutations is not fully understood. Here, we investigated the change of cell migration and invasion in vitro and the role of NPM1 mutations in this process. In our study, NIH3T3 cells were transfected with plasmids encoding NPM1 mutation A (NPM1 mA), and the cell chemotactic response in vitro was evaluated by cell migration and invasion assays. In addition, the expression levels of MMP-2, MMP-9 and CXCR4 were assayed by quantitative real-time PCR and western blotting. Our findings suggested that the migration and invasion of NIH3T3 cells were significantly enhanced after transfection with NPM1 mA (p

Water content of Korean pine samples was studied using near infrared spectrascopy (NIR) combinded with parial least squares regression (PLS) analysis. Seven typical wave lengths were selceted to characterize the wood water content of Korean pine. Prediction models of wood water content were developed based on the original NIR spectra at seven varied wave lengths. The best model was showed between wavelengths from 1000 to 2100 nm with correlation coefficient (R) of 0.9871, standard error of calibration (SEC) and root mean square error of calibration (RMSEC) of 0.0337 and 0.0334, respectively. The correlation coefficient（R） for model validation was 0.9817 with standard error of prediction (SEP) and root mean square error of prediction (RMSEP) of 0.0470 and 0.0465, respectively. This study indicated that NIR is a useful tool for fast prediction of wood water content of Korean pine. The modeling proficiency could be improved significantly for some certain wave length. It could be a research focus for future related studies.