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A concise strategy for the synthesis of vinylsilanes from an iron-catalyzed regio- and stereoselective hydrosilylation of terminal alkynes has been developed. The catalyst and reagents are commercially available and easy to handle, providing a simple and practical method for iron-catalyzed anti-Markovnikov hydrosilylation with a good functional group tolerance. [ABSTRACT FROM AUTHOR]

Grassbur is a destructive and invasive weed in pastures, and its burs can cause gastric damage to animals. The strong adaptability and reproductive potential of grassbur are partly due to a unique germination mechanism whereby twin seeds develop in a single bur: one seed germinates, but the other remains dormant. To investigate the molecular mechanism of seed germination in twin seeds, we used isobaric tags for relative and absolute quantitation (iTRAQ) to perform a dynamic proteomic analysis of germination and dormancy. A total of 1,984 proteins were identified, 161 of which were considered to be differentially accumulated. The differentially accumulated proteins comprised 102 up-regulated and 59 down-regulated proteins. These proteins were grouped into seven functional categories, ribosomal proteins being the predominant group. The authenticity and accuracy of the results were confirmed by enzyme-linked immunosorbent assay (ELISA) and quantitative real-time reverse transcription-PCR (qPCR). A dynamic proteomic analysis revealed that ribosome synthesis and carbohydrate metabolism affect seed germination possibly through the phosphoinositide 3-kinase (PI3K) pathway. As the PI3K pathway is generally activated by insulin, analyses of seeds treated with exogenous insulin by qPCR, ELISA and iTRAQ confirmed that the PI3K pathway can be activated, which suppresses dormancy and promotes germination in twin grassbur seeds. Together, these results show that the PI3K pathway may play roles in stimulating seed germination in grassbur by modulating ribosomal synthesis and carbohydrate metabolism. [ABSTRACT FROM AUTHOR]

The consensus problem of heterogeneous multiagent systems composed of first-order and second-order agent is investigated. A linear consensus protocol is proposed. Based on frequency domain method, the sufficient conditions of achieving consensus are obtained. If communication topology contains spanning tree and some conditions can be satisfied on control gains, consensus can be achieved. Then, a linear consensus protocol with time delay is proposed. In this case, consensus is dependent only on system coupling strength, each agent input time delay, but independent of communication delay. Finally, numerical simulations are provided to illustrate the effectiveness of the theoretical result. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), a chemical used in many consumer products, interferes with the endocrine system of mammals, including humans. The aim of the present study was to investigate the effect of BPA on spermatogenesis and semen quality. The objective of this study was to assess the effects of BPA on mouse spermatogenesis. CD1 mice were used in all experiments. Mice were treated with different doses of BPA (0, 20 and 40 µg kg[sup -1] day[sup -1]from postnatal Day (PND) 3 to PND21, PND 35 or PND49. After 5 weeks BPA treatment, oestrogen receptor α expression was increased in mouse testis, whereas the meiotic progression of germ cells was slowed. Thus, both the quality and quantity of spermatozoa were decreased in 7-week-old mice. However, BPA had no effect on DNA methylation of imprinted genes such as Igf2, Igf2r, Peg3 and H19, in germ cells. In addition, exposure of male mice to BPA resulted in abnormal offspring that were smaller with a low-quality pelage when they were 35 days old. In conclusion, BPA hampers spermatogenesis and the subsequent development of offspring. Bisphenol A (BPA), a chemical used in many consumer products, interferes with the endocrine system of mammals, including humans. The present study investigated the effects of BPA on spermatogenesis and semen quality, and found that BPA decreased both the quantity and quality of mouse spermatozoa, resulting in abnormal offspring that were smaller and had a low-quality pelage. The results demonstrate that BPA hampers spermatogenesis and the development of offspring. [ABSTRACT FROM AUTHOR]

The solubilities of sodium p-toluenesulfonate (NaPTS), sodium sulfite (Na2SO3), and sodium p-methylphenoxide (NaCRS) in aqueous NaOH solutions and Na2SO3 in aqueous ethanol solutions were investigated using a dynamic method over the temperature range from 277 to 341 K at atmospheric pressure. The experimental results showed that the solubilities of NaPTS, Na2SO3, and NaCRS in aqueous NaOH solutions and Na2SO3 in aqueous ethanol solutions decreased distinctly with the solute-free mass fraction of NaOH (w40) and ethanol (w50). Further, there were obvious transition points in the solubility-temperature curves of NaPTS and Na2SO3 in aqueous NaOH solutions, and the transition points shifted to lower temperature as w40 rose. The forming of transition point was due to the different equilibrium solid phase, which was revealed by characterization of the equilibrium solid phase. But the transition points in the solubility-temperature curves of Na2SO3 in aqueous ethanol solutions remained constant at different w50 values. As the temperature rose, the solubilities of NaPTS and NaCRS in aqueous NaOH solutions increased, while the solubilities of Na2SO3 increased at first and then decreased after the transition points in both aqueous NaOH and ethanol solutions. The experimental data were correlated with the electrolyte nonrandom two-liquid (E-NRTL) model, and model parameters were determined simultaneously. On the basis of the solubility difference between Na2SO3 and NaCRS, a new process for reusing the NaOH in the alkali fusion reaction residue was proposed theoretically. [ABSTRACT FROM AUTHOR]

The solubilities of sodium 1- and 2-naphthalenesulfonate (1- and 2-SNS) in aqueous sodium hydroxide solutions were measured over the temperature range from 276 to 337 K at atmospheric pressure by a dynamic method. The experimental results showed that the solubilities of 1- and 2-SNS both increased with temperature and decreased with concentrations of aqueous sodium hydroxide solutions. The experimental data were correlated with the new electrolyte nonrandom two-liquid (E-NRTL) model. The calculated results showed good agreement with the experimental data. A new strategy, based on the solubility difference between 1- and 2-SNS in aqueous sodium hydroxide solutions, was carried out in laboratory scale. This new strategy, in which the current process of blowing naphthalene was replaced by removing the byproduct according to the solubility difference, overcame the drawbacks of blowing naphthalene and made a good separation effect. The best separation effect was attained when the concentration of aqueous sodium hydroxide solution was 0.07 and the operating temperature was 298.15 K. The purities of obtained 1- and 2-SNS were 0.8369 and 0.9854 in this operating condition, respectively. The new strategy has potential in industrial application for optimizing the production of 2-naphthol. [ABSTRACT FROM AUTHOR]

Thin-film composite (TFC) nanofiltration (NF) membranes were developed by terephthaloyl chloride (TPC) crosslinked the hydroxyl ended groups of hyperbranched polyester (HPE) on polyacrylonitrile (PAN) support. Fourier transform infrared spectroscopy (FITR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) indicated that a thin layer of crosslinked HPE molecules were deposited on PAN porous membrane surface successfully. The preparation conditions were also optimized. The separation performance of PAN-HPE-TPC NF membranes are mainly related with the concentration of monomer in the aqueous phase rather than that in the organic phase. Water permeability and salts rejections of the membranes were measured. The flux and rejection of these NF membranes for Na2SO4 (1 g/L) reached 11.43 L/m²h and 96.5% under 0.6 MPa, respectively. At the same time, the nanofiltration properties were compared with other membranes prepared with hyperbranched polymers. All NF membranes prepared with hyperbranched polymers showed relative high permeate flux. [ABSTRACT FROM AUTHOR]

Solubilities of sebacic acid in binary ethanol + water solvent mixtures were measured by the dynamic method using a laser monitoring observation technique at a temperature range from (288 to 352) K. The mole fraction of ethanol in the solvent mixtures ranges from 0 to 1. The melting temperature and enthalpy of fusion of sebacic acid were determined by differential scanning calorimetry. The experimental results show that the slope of the solubility−temperature curve increases significantly with an increase in the mole fraction of ethanol in the solvent. The Wilson equation is applied to describe measured systems. The model parameters of the Wilson equation were expressed as a function of temperature. [ABSTRACT FROM AUTHOR]

The solubilities of the sodium 2-chlorotoluene-4-sulfonate (CTSNa) in water, methanol, formic acid, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), binary (methanol + water) mixed solvents, and binary (ethanol + water) mixed solvents were determined experimentally over the temperature range from (280 to 335) K at atmospheric pressure using a dynamic method. The mole fraction of water in the two solvent mixtures ranged from 0.0000 to 1.0000 and 0.2006 to 1.0000, respectively. A synergistic effect on CTSNa solubility was observed with the maximum solubility at solute-free mole fraction of ethanol x20 = 0.2082 and solute-free mole fraction of methanol x30 = 0.3985, respectively. The solubility data were correlated with the thermodynamic electrolyte nonrandom two-liquid (E-NRTL) model and the root-mean-square deviations of solubility temperature varied from (0.24 to 1.10) K. [ABSTRACT FROM AUTHOR]

The nitration process as one step in 2-amino-5-chloro-4-methylbenzenesulfonic acid synthesis was improved by optimizing nitration reaction conditions, improving product separation method to eliminate salty scrap acid and cycle use of the concentrated sulfuric acid. The effect of various parameters such as temperature, quality of fuming sulfuric acid, quality of fuming nitric acid, and reaction time was studied for optimization of the nitration reaction condition. In the optimum conditions, the mass ratio of fuming sulfuric acid to sodium 2-chlorotoluene-4-sulfonate and molar ratio of fuming nitric acid to sodium 2-chlorotoluene-4-sulfonate were 4 and 1.05, respectively. The reaction temperature was -5 °C, and the time of reaction was 3 h. By applying the optimum reaction conditions, the yield of nitration reaction was increased to 91%, larger than that of the current industrial process whose yield is only 65.7%. The solubilities of sodium 2-chloro-5-nitrotoluene-4-sulfonate in aqueous sulfuric acid solutions were determined by a dynamic method, and the results showed that the lowest sodium 2-chloro-5-nitrotoluene-4-sulfonate solubility was exhibited in 0.7 mass fraction aqueous sulfuric acid solutions. So the product sodium 2-chloro-5-nitrotoluene-4-sulfonate of nitration reaction was separated by filtration from 0.7 mass fraction aqueous sulfuric acid solutions, and the obtained concentrated aqueous sulfuric acid solution was reused. [ABSTRACT FROM AUTHOR]

The solubilities of the sodium 2-chlorotoluene-4-sulfonate (CTSNa) in water, methanol, formic acid, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), binary (methanol + water) mixed solvents, and binary (ethanol + water) mixed solvents were determined experimentally over the temperature range from (280 to 335) K at atmospheric pressure using a dynamic method. The mole fraction of water in the two solvent mixtures ranged from 0.0000 to 1.0000 and 0.2006 to 1.0000, respectively. A synergistic effect on CTSNa solubility was observed with the maximum solubility at solute-free mole fraction of ethanol x20 = 0.2082 and solute-free mole fraction of methanol x30 = 0.3985, respectively. The solubility data were correlated with the thermodynamic electrolyte nonrandom two-liquid (E-NRTL) model and the root-mean-square deviations of solubility temperature varied from (0.24 to 1.10) K. [ABSTRACT FROM AUTHOR]

Offshore wind power structures are subjected to complex dynamic loads in marine environment during their service. At present, the real sea conditions can be simulated to the maximum extent by the mixed test technology of boundary layer wind tunnels, wave pools and shaking tables. However, due to the high cost of test and the lack of a complete and mature combined simulation laboratory which can be operated for wind, wave and seismic loads, it is difficult to carry out such joint tests. It is advantageous to use self-developed mechanical devices to simulate marine environmental loads within the controllable errors and which is in simple operation. A series of dynamic model tests were carried out on saturated sand foundation in order to explore the feasibility of studying dynamic response of offshore wind power pile foundations through simulating marine environmental loads by simplified methods. Based on Stokes second-order wave theory and harmonic superposition method, the time history of wind, wave and current load is derived and programmed, then the wind, wave and current load on offshore fan model structure is simulated by using self-developed complex dynamic loading system. Finally, the dynamic response of single pile foundation in saturated sand under complex load is analyzed according to the test results. The test results show that the load displacement curve of single pile foundation in saturated sand is of work hardening type. The maximum pile bending moment at the peak of dynamic load increases with the increase of loading times, but the cumulative effect of bending moment caused by the change of load amplitude should be considered. The dynamic load in marine environment will cause the increase of pore pressure around the pile, but the increase of pore pressure on loading side is not obvious in comparison to that on the opposite side. The displacement change of pile body is basically in accordance with the fluctuation trend of test load and increases with load. The cumulative rate of displacement of single pile decreases with the increase of number of cycles under the long-term cyclic wind wave load. In this study, the method combining theoretical calculation of wind, wave and current load with model test of complex loading system can consider the characteristics of dynamic loads of marine environment more accurately, compared with the empirically determined cyclic load waveforms in conventional tests, the obtained response law is more in accord with actual sea conditions. • A series of dynamic model tests were carried out on saturated sand by simplified methods. • The complex marine load on OWT model is simulated by using self-developed dynamic loading system. • The dynamic response of pile in saturated sand under complex load can be obtained according to the test results. • The method combining theoretical calculation with model test of loading system can consider marine loads accurately. [ABSTRACT FROM AUTHOR]

Toseparate a salt mixture (mainly consisting of Na2CO3and Na2SO4) which is formedfrom the 4,4′-diaminostilbene-2,2′-disulfonic acid wastewatertreatment, the solubility data of Na2CO3andNaHCO3in Na2SO4–water solventmixtures were measured using a dynamic method over the 275–335K temperature range. The solute-free mass fraction of Na2SO4in the solvent mixtures extended from 0 to 0.25. Thesolubility of Na2CO3and NaHCO3inNa2SO4–water solvent mixtures decreasedwith addition of Na2SO4. With rising temperature,the solubility of NaHCO3increased while the solubilityof Na2CO3increased at first and then decreasedafter transition points. The experimental data were correlated withthe electrolyte nonrandom two-liquid model. The root-mean-square deviationsof solubility temperature varied from 0.35 to 1.50 K. Based on thesolubility data of this work, a new strategy for separating the Na2CO3and Na2SO4mixture wasproposed theoretically. [ABSTRACT FROM AUTHOR]

In the present study, we established an in vitro culture system suitable for generating fertilizable oocytes from premeiotic mouse female germ cells. These results were achieved after first establishing an in vitro culture system allowing immature oocytes from 12-14 day- old mice to reach meiotic maturation through culture onto preantral granulosa cell (PAGC) monolayers in the presence of Activin A (ActA). To generate mature oocytes from premeiotic germ cells, pieces of ovaries from 12.5 days post coitum (dpc) embryos were cultured in medium supplemented with ActA for 28 days and the oocytes formed within the explants were isolated and cocultured onto PAGC monolayers in the presence of ActA for 6-7 days. The oocytes were then subjected to a final meiotic maturation assay to evaluate their capability to undergo germinal vesicle break down (GVBD) and reach the metaphase II (MII) stage. We found that during the first 28 days of culture, a significant number of oocytes within the ovarian explants reached nearly full growth and formed preantral follicle-like structures with the surrounding somatic cells. GSH level and Cx37 expression in the oocytes within the explants were indicative of proper developmental conditions. Moreover, the imprinting of Igf2r and Peg3 genes in these oocytes was correctly established. Further culture onto PAGCs in the presence of ActA allowed about 16% of the oocytes to undergo GVBD, among which 17% reached the MII stage during the final 16-18 hr maturation culture. These MII oocytes showed normal spindle and chromosome assembly and a correct ERK1/2 activity. About 35% of the in vitro matured oocytes were fertilized and 53.44% of them were able to reach the 2-cell stage. Finally, around 7% of the 2-cell embryos developed to the morula/blastocyst stage. [ABSTRACT FROM AUTHOR]

Interindividual variability of cytochrome P450 (CYP) 3A inhibition by grapefruit juice was investigated in relation to CYP3A5 and multidrug resistance gene (MDR) 1 genetic polymorphisms in Chinese Han, Uygur, and Kazakh healthy subjects. The measurement of urinary 6β-hydroxycortisol/cortisol ratio was used to evaluate CYP3A activity in vivo by high-performance liquid chromatography CYP3A5 *3 and MDR1 C1236T, G2677T/A, and C3435T polymorphisms were analyzed by polymerase chain reaction restriction fragment length polymorphism. After grapefruit juice intake, urinary ratios significantly decreased in 3 Chinese ethnic groups (P < .001). Kazakh had a larger decrease of urinary ratio compared to that of Han (P < .05), and the latter had similar decrease with Uygur. Furthermore, Chinese healthy subjects carrying CYP3A5*3/*3 and MDR11236-2677-3435 T-T-T/T-T-T genotypes were found to have the largest reduction of urinary ratio (mean, 61.4%; 95% confidence interval, 53.4%-69.5%), whereas *1/*3 subjects carrying MDR11236-2677-3435 C-G-C/C-G-C genotypes had the lowest reduction (mean, 25.9%; 95% confidence interval, 3.1%-48.8%; P < .01). In conclusion, both CYP3A5*3 and MDRl variants influenced the extent of CYP3A inhibition by grapefruit juice in Chinese healthy subjects. The genetic variations influencing the CYP3A inhibitive phenotype might be helpful to explain the individual variability of grapefruit juice-drug interactions. [ABSTRACT FROM AUTHOR]

CYP2C19 and CYP2E1 show great genetic differences between Orientals and Caucasians. The objective of this study was to investigate the genotype and allele distribution patterns of CYP2C19 and CYP2E1 polymorphisms among healthy participants in mainland Chinese Kazakh, Uygur and Han populations by the PCR–restriction fragment length polymorphism technique. The allele frequencies of CYP2C19*2, CYP2E1*5B and CYP2E1*6 were significantly lower in the Chinese Kazakh (15.4, 11.2 and 14.5%, respectively) (P<0.05) and Uygur (16.1, 12.1 and 18.8%) (P<0.05) populations than that in the Chinese Han population (28.8, 19.4 and 26.2%), but the frequencies of CYP2C19*3 were similar among the three populations (8.0, 9.4 and 7.2%). Frequencies of the three combined genotypes, one for predicted CYP2C19 poor metabolizers and two for predicted high levels of CYP2E1 transcription, were significantly lower in the Chinese Kazakh (7.5, 19.6 and 28.0%, respectively) (P<0.05, χ2-test) and Uygur (8.1, 22.8 and 33.6%) (P<0.05) populations compared with the Chinese Han population (16.5, 35.9 and 44.7%). The present research shows that frequencies of the functional single-nucleotide polymorphisms in the CYP2C19 and CYP2E1 genes vary in the Chinese Kazakh, Uygur and Han populations, suggesting that disease susceptibilities or drug responses associated with enzyme activities of CYP2C19 and CYP2E1 may differ in the diverse ethnic populations in mainland China.Journal of Human Genetics (2009) 54, 372–375; doi:10.1038/jhg.2009.41; published online 15 May 2009 [ABSTRACT FROM AUTHOR]

Solubilities of nonanedioic acid in binary ethanol + water solvent mixtures have been determined by the dynamic method using a laser monitoring observation technique over a temperature range from (292.35 to 345.52) K and a solvent composition, mole fraction of ethanol of solute-free x20, range from 0.0 to 1.0. The experimental results showed that in pure water the solubility of nonanedioic acid increased slowly with temperature below 342.77 K but increased significantly above 342.77 K. The nonanedioic acid + ethanol + water system was found to exhibit a synergistic effect on solubility. The fusion enthalpy and melting temperature of nonanedioic acid were measured by differential scanning calorimetry. The modified λhequation, the Wilson equation, and the NRTL equation have been applied to correlate a subset of the experimental data. These models can successfully describe the solubility of nonanedioic acid in the binary mixtures with an ethanol mole fraction higher or equal to 0.2811. [ABSTRACT FROM AUTHOR]

The solubilities of sebacic acid in mixed solvents n-propanol + water have been measured by a dynamic method using a laser monitoring observation technique over a temperature range (288 to 351) K. A synergistic effect on solubility was found to occur in sebacic acid + n-propanol + water mixed systems. To detect the synergistic effect, solubilities of sebacic acid in 14.35 %, 36.97 %, 79.81 %, and 90.00 % mole fraction ethanol aqueous solution were determined to supplement our previous report. A weak synergistic effect was found for sebacic acid + ethanol + water mixed systems. The solid−liquid equilibrium (SLE) data have been fitted using the λhequation, the Wilson equation, and the NRTL equation. The comparison between the experimental and the calculated solubilities for the three models is reasonable, and the root-mean-square deviations for each system range from (0.30 to 1.95) K. [ABSTRACT FROM AUTHOR]