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Owing to far-ranging industrial applications and theoretical researches, tailored synthesis of well-defined nanocrystals has attracted substantial research interest. Herein, β-AgI nanoplates have been synthesized through a facile polyvinylpyrrolidone (PVP)-assisted-aqueous-solution (PAAS) method under mild conditions. The parametric studies on the effect of ratio of reactants, solvents and surfactants were performed, revealing that a molar ratio of I(-) to Ag(+) of 1.2 in deionized water and the presence of appropriate PVP as stabilizing agent can stimulate the preferred orientation growth of AgI nanoplates. The as-synthesized AgI nanoplates exhibit excellent photocatalytic activity and enhanced durability towards the degradation of organics, i.e., rhodamine B (RhB), under visible light illumination in comparison with corresponding bulk nanoparticles. A possible photocatalytic reaction mechanism was discussed, revealing O2˙(-) and h(+) are main reactive species and free ˙OH radicals in solution also contribute to the degradation reaction. The superior photocatalytic performance renders the as-achieved AgI nanoplates promising candidates for applications in the fields of environmental purification or water disinfection. The present work opens an avenue to the synthesis of other shaped silver halide nanophotocatalysts.

Macro fatigue cracks are expected to occur in valve bridges of cylinder head when engine is operating in normal working condition. In order to determine the causes of these failures, stress analysis is carried out using finite element method with a concern of temperature dependency of material properties. Mechanical and thermal properties of material tested at high temperatures are applied to the finite element analysis. Furthermore, temperatures of the cylinder head in actual working condition are measured to validate the simulation results of finite element analysis. After that, stress computation is performed and the regions of stress concentration on the flame deck surface are obtained. The analysis results of stress show that the regions of stress concentration are in agreement with the actual failure regions of the cylinder head. When analyzing the failures on the flame deck surface of a cylinder head by evaluating stress concentration, temperature’s effect on mechanical strength of material should not be ignored. The methodology of failure analysis proposed in this paper is time-saving and also relatively accurate and predictive in actual engineering practice.

Stepped-isothermal fatigue failure is the main failure mechanism of modern engine pistons under bench reliability test condition. This paper presents a methodology for stepped-isothermal fatigue analysis of engine pistons, which consists of a fatigue criterion, evaluation of temperature and stress distribution by finite element analysis and the final life prediction. The major character of the methodology is the fatigue definition of engine pistons with respect to engine load change cycle and a damage-based fatigue criterion accounting for the nonlinear creep–fatigue damage. Taking as an example, the fatigue life of an engine piston was predicted by the proposed analysis procedures. The analysis results showed that the most critical area was located in the throat edge. Moreover, the proposed methodology can give a relatively accurate and reasonable life prediction for an engine piston under the loading condition of bench reliability test, with a benefit of decreasing the needed component's reliability tests and design time.

A model is developed herein for predicting the fatigue life of creep-fatigue damage interaction, which is induced by combined high frequency mechanical loading and low frequency temperature variation, i.e. stepped-isothermal fatigue loading. The model is derived from continuum damage mechanics. In the model, the interaction between creep and fatigue damage is considered to be nonlinear. To validate the proposed model, a cast aluminum alloy is fatigue tested at 200–350 °C and 350–400 °C. The results show that good agreement can be achieved between predicted life and experimental data.

High cycle fatigue tests of a cast Al-12Si-CuNiMg alloy are carried out under different stress amplitudes at room temperature. The scanning and transmission electron microscopy observations are used to examine the fracture surfaces and dislocation structures of the tested material, respectively. The results show that the fatigue damage originates from the microstructural defects, and the fracture surface morphology is typical quasi-cleavage fracture. With the increasing strain amplitude, the material fatigue life obviously decreases; however, the dislocation density increases significantly, which leads to the formation of the dislocation walls and cells. Under the cycle loading, the eutectic Si phase and the secondary particles undergo fracture. The pinning effect of the precipitates on the dislocations becomes obvious, indicating that the Al-12Si-CuNiMg alloy has the cyclic hardening characteristic.

Microstructure evolution of the Al–12Si–CuNiMg alloy under high temperature low cycle fatigue was investigated with scanning and transmission electron microscopy. The alloy exhibits cyclic softening at diverse total strain amplitudes and loading temperatures. The material fatigue life obviously decreases with the increase of the strain amplitude at the same temperature. However, fatigue life increases and microstructure improves with temperature increase at the same strain amplitude. At certain loading temperatures and strain amplitudes, the microstructure can be refined. The fracture morphology changes gradually from brittle quasi-cleavage fracture, with numerous small cracks, to quasi-cleavage fracture with numerous small dimple gliding fractures.

In the present work numerical analysis for effects of shot peening on fatigue crack growth are reported and discussed. Simulations reported in the present work use irreversible cohesive zone model and are based on experimental data for a Nickel-based superalloy. The capability of the cohesive zone model to catch the effects of short crack is investigated. The two-dimensional computations fit known experimental records in the CT specimen which confirms that the cohesive zone model has the potential for engineering application. The fatigue crack growth of shot-peened specimens are studied for different loading amplitudes and different shot peening intensities. The numerical results reveal that the crack initiation position and time depend not only on the shot peening intensity but also on the cyclic loading amplitude. Retardation of fatigue crack growth is more effective at lower loading amplitude for shot-peened specimens, and higher applied loading will eliminate the beneficial effects of shot peening.

A novel kind of transferrin imprinted polymer particles was synthesized by a hierarchical strategy. First, transferrin was immobilized on silica beads by non-covalent absorption. Then, a pre-polymerization mixture, composed of 1,4-bis(acryloyl)piperazine, methacrylamide, methacrylic acid, ammonium sulfate and polyoxyethylene sorbitan monolaurate, was irrigated into the pores of silica particles, and polymerized at 25 °C. Finally, the silica matrix was etched with ammonium hydrogen fluoride, not only to remove the template protein, but also to expose protein recognition sites on the surface of the imprinted polymer. The binding capacity of the transferrin-imprinted particles is 6.3 mg of protein per gram of material, and the time required to reach adsorption equilibrium was less than 10 min. The imprinting factor of transferrin is ca. 3.3 in the presence of ribonuclease B, cytochrome c and β-lactoglobulin. The results indicate that these imprinted polymer particles can recognize transferrin with good selectivity, high binding capacity and fast mass transfer. They may be applied as an artificial antibody to remove the high abundance proteins in plasma.

In recent years, the detection of pesticide residues is an important research field in China. Traditional methods which include biochemical methods and chromatography methods have high requirement for the experimental environment. Thus traditional methods cannot complete tasks in a short time. NIR spectrum represents physical features of matters and pesticide residues on fruit can change the NIR spectrum reflected by surface. It is feasible to make sure that if there is pesticide residues on fruit or not by analyzing the NIR spectrum reflected by surface. The method of spectrum analysis is easy to conduct and faster than traditional methods.

Lysozyme is a crucially spread hydrolase in organisms that can defend against bacterial infection in innate immunity. In this study, we successfully sequenced the coding region of chicken-type lysozyme gene ( PoLysC ) in Paralichthys olivaceus and identified nine single nucleotide polymorphisms (SNPs). We then amplified the 2500 bp promoter region of lysozyme and identified the eight sites of polymorphisms. All SNPs were genotyped between susceptible and resistance groups after Listonella anguillarum challenge. One of these SNP sites in the codon of PoLysC was genotyped and determined to be a significant marker by analyzing its distribution in the susceptible and resistant groups. As a nonsynonymous mutation, the frequency of 140G/C genotype in the resistant group was higher (67.74%) than that in the susceptible group (32.26%). The linkage between SNP140 and polymorphisms in the promoter region was also studied. Results revealed that the frequency of haplotype CC -536 /CC -1200 /GG 140 in the resistance group was significantly higher than that in the susceptible group. The quantitative expression of lysozyme gene in the resistant group was also higher than that in the susceptible group. This finding indicated that the linkage between polymorphism −536 and −1200 sites in promoter and SNP140 in codon sequence was associated with the resistance of P. olivaceus to L. anguillarum. All these results suggest that the mutations in promoter and coding region were related to changes in PoLysC for resisting L. anguillarum . The haplotype CC -536 /CC -1200 /GG 140 was a potential marker and can thus be applied to selective breeding for the disease resistance of P. olivaceus .

Exon-intron structure analysis of CpIAA genes. (DOCX 35 kb)

The expression levels of AtIAA genes response to various hormones. (DOCX 294 kb)

The scores of the search results for CpIAA proteins. (DOCX 12 kb)

The relationships of IAA genes between papaya and rice. (DOCX 77 kb)

The primer sequences of papaya Aux/IAA family genes. (DOCX 11 kb)

The numbers of stress-related cis-elements in the upstream 1.5-kb regions of the CpIAA and AtIAA family genes. (DOCX 13 kb)

The low-cycle fatigue behaviour of a cast Al–12Si–CuNiMg alloy, with a high content of Si, is investigated at 200, 350 and 400 °C. The fatigue test results show that the alloy exhibits symmetrical hysteresis loops, moderate cyclic softening and higher fatigue resistance at higher temperature. The fracture surface analysis reveals that more tear ridges are formed at higher temperature, which strongly affect the fatigue resistance. Furthermore, evaluation of the material fatigue resistance using an energy-based Halford–Marrow model indicates that the material's ability to absorb and dissipate plastic strain energy is enhanced as temperature increases.

Background Circulating follicular helper T (Tfh) cells are a heterogeneous population of CD4+ helper T cells that promotes pathogenic immune responses in autoimmune diseases. In this study, we examined the status of different subpopulations of Tfh cells in peripheral circulation and their associations with various clinical characteristics of IgA vasculitis (IgAV). Methods According to the phenotypic expressions of different molecules, focus was given on six subpopulations of Tfh cells: CD4+CXCR5+, CD4+CXCR5+ICOS+, CD4+CXCR5+ICOS+PD-1+, CD4+CXCR5+ICOShighPD-1high, CD4+CXCR5+ICOS−PD-1+, and CXCR5+CD45RA−IL-21+. The frequencies of these six subpopulations and the circulating level of Tfh-related cytokine interleukin 21 (IL-21) were measured from 27 patients with IgAV and 15 healthy controls (HC) by flow cytometry and flow cytometric bead array, respectively. Results Significantly higher frequencies of CD4+CXCR5+, CD4+CXCR5+ICOS+, CD4+CXCR5+ICOS+PD-1+, CD4+CXCR5+ICOShighPD-1high and CXCR5+CD45RA−IL-21+ Tfh cells, as well as higher levels of plasma IL-21, were detected in IgAV patients compared to HC. The level of each Tfh subpopulation varied by the presenting symptoms of IgAV, but did not differ between patients treated or not treated with glucocorticoids. When the disease entered the remission stage following treatment, circulating levels of CD4+CXCR5+, CD4+CXCR5+ICOS+, CD4+CXCR5+ICOS+PD-1+, CD4+CXCR5+ICOShighPD-1high and CXCR5+CD45RA−IL-21+ Tfh cells, as well as plasma IL-21 levels were reduced. Among the six subpopulations of Tfh cells, both CD4+CXCR5+ICOS+ and CXCR5+CD45RA−IL-21+ significantly and positively correlated with serum IgA and plasma IL-21 levels, but only CXCR5+CD45RA−IL-21+ significantly and negatively correlated with the serum C4 level. Conclusions Tfh cells may differentially contribute to the development of IgAV or predict disease progression. These findings provide novel insights in the pathogenesis of IgAV and may benefit treatment development targeting organ-specific presenting symptoms of IgAV.

Following the two rounds of whole-genome duplication (WGD) during deuterosome evolution, a third genome duplication occurred in the ray-fined fish lineage and is considered to be responsible for the teleost-specific lineage diversification and regulation mechanisms. As a receptor-regulated SMAD (R-SMAD), the function ofSMAD3was widely studied in mammals. However, limited information of its role or putative paralogs is available in ray-finned fishes. In this study, twoSMAD3paralogs were first identified in the transcriptome and genome of Japanese flounder (Paralichthys olivaceus). We also exploredSMAD3duplication in other selected species. Following identification, genomic structure, phylogenetic reconstruction, and synteny analyses performed by MrBayes and online bioinformatic tools confirmed thatsmad3a/3bmost likely originated from the teleost-specific WGD. Additionally, selection pressure analysis and expression pattern of the two genes performed by PAML and quantitative real-time PCR (qRT-PCR) revealed evidence of subfunctionalization of the twoSMAD3paralogs in teleost. Our results indicate that twoSMAD3genes originate from teleost-specific WGD, remain transcriptionally active, and may have likely undergone subfunctionalization. This study provides novel insights to the evolution fates ofsmad3a/3band draws attentions to future function analysis ofSMAD3gene family.

Reproduction allows organisms to produce offspring. Animals shift from immature juveniles into mature adults and become capable of sexual reproduction during puberty, which culminates in the first spermiation and sperm hydration or ovulation. Reproduction is closely related to the precise control of the hypothalamic–pituitary–gonadal (HPG) axis. Kisspeptin peptides are considered as the important regulator of HPG axis in mammalian. However, the current understanding of kisspeptin in flatfish is not comprehensive. In this study, we cloned and analyzed the kiss2 and kissr2 genes in Cynoglossus semilaevis. Interesting alternative splicing in the 5′-untranslated regions (UTR) of the Cskissr2 gene was found. The expression profiles of Cskiss2 and Cskissr2 showed relative high messenger RNA (mRNA) levels at the late gastrula stage during embryonic development, at total length = 40 mm during early gonadal differentiation, and in the brains and gonads of all investigated tissues. These results suggested that the kisspeptin system participated in embryogenesis and in the regulation of gonadal differentiation and development. Considering that the control and regulatory mechanisms of kisspeptin in the central reproductive axis are still unclear, we documented that the intramuscular injection of kisspeptin caused different sGnRH and cGnRH mRNA levels in a dose- and tissue-dependent manner. The mRNA expressions of FSH and LH were stimulated in the ovary and were inhibited in the testis under the kisspeptin treatments. These results provided foundations for understanding the roles of kisspeptin in the neuroendocrine system in fish. The manipulation of the kisspeptin system may provide new opportunities to control the gonadal development and even reproduction in fish.

An analytical method is proposed to calculate the interaction between operation stresses and shot peening caused residual stresses. The obtained variation of residual stress is integrated into Findley model to predict the fatigue life of shot-peened materials. Biaxial stress state is taken into account in conventional Findley model, and critical plane is studied for both in-plane and out-of-plane shear stress. In the end, taking example for AISI 4340 steel, the prediction of fatigue life is made for two different shot peening conditions. A good agreement between measurements and predictions can be observed.

A mechanism for conversion of thiols into disulfides and dihydrogen catalyzed by CpMn(CO) 3 was studied in detail with the aid of density functional theory computations. Four major steps are involved in both of the two possible pathways (path1 and path2): (1) a ligand substitution process (dissociation of one carbonyl ligand and subsequent addition of RSH to the metal center); (2) intermolecular hydride migration; (3) addition of RSH and release of dihydrogen; (4) production of S 2 R 2 and regeneration of the catalyst. Migration of the hydrogen from RSH to Cp ring can not be completed in one step, but need to form the key intermediate CpMnH(CO) 2 SR first. Ligand substitution process is the rate-determined reaction step. Path1 is the dominant pathway compared with path2, which mainly results from difficult formation of the five-member transition state in path2.

Since the launching of tertiary oil recovery, the performance requirements of polymer solution increasing, the polymer solution is more difficult to meet the needs of the scene. It could solve poor profile control, salt-tolerant, and poor performance that crosslinking agent was added to polymer solution. Therefore, chromium acetate crosslinker was synthesized, and the synthesis conditions were optimized, and the performance of crosslinking agent was evaluated. Through optimization, the optimum conditions of chromium acetate synthesis was: reaction time 10 h, reaction temperature 80°C, the molar ratio of acetic acid and potassium dichromate than or equal to 24 : 1. Performance evaluation showed that adding crosslinking agent could significantly increase the viscosity of the polymer solution, could significantly improve the resistance coefficient and residual resistance of the polymer solution, and could play a good role profile flooding. Studies showed that when salinity and ion content changed, the crosslinking mechanism of changed. Through the study of molecule coil size at room temperature, the molecule coil size would slightly decline after 1 h, suggesting that crosslinking mechanism was intramolecular crosslinking reaction occurs at first, and then intermolecular crosslinking reaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Damage models have been applied in engineering applications. In the present work both Gurson–Tvergaard–Needleman (GTN) model and the progressive damage model have been employed to describe plastic deformation and damage behaviour in the tensile bars and threaded bolts. The predictive capabilities of the models are critically assessed. The parameters in the damage models are identified from uniaxial tensile tests. The models are applied to predict failure of the threaded bolts. Numerical results reveal both models agree with experimental data in uniaxial tension and in threaded bolts. The overall results do not show substantial differences. However, damage evolutions from both damage models display very different developments. Whereas the GTN model confirms damage nucleation in the specimen center of the uniaxial tensile bars, as observed in experiments, the progressive damage model predicts damage starts from the specimen surface where the plastic strain reaches its maximum. In threaded bolts both models do not show significant deviations in predicting the ultimate loading. The progressive damage model without stress triaxiality consideration predicts an unrealistic ductile fracture process and cannot be applied to metallic materials.

Quantification of shot peening effects in fatigue life prediction becomes increasingly important in industry. The goal of the present work is to find out an engineering method for predicting the residual stress variations and to give a quantitative conservative estimate about the improvement from shot peening. The variations of residual stress caused by shot peening can be described by three sets of ordinary differential equations which have to be solved with the initial residual stresses and the initial plastic strain. It is shown that the equations are valid for materials on free surface and in position where the residual stress reaches maximum value. The equations provide the basis for predicting residual stress variations in the whole shot-peened layer. The nonlinear residual stress variations can be replaced by a multi-linear uniaxial method introduced in the present work. The accuracy of the multi-linear method is verified by detailed finite element computations for uniaxial tension bars and notched specimens. The applicability of the present method to rotor disc is investigated. Discrepancy between the finite element analysis and the multi-linear method is trivial for engine design if the maximum loading strain is limited by 2.5%.

The fatigue crack growth, incorporating effects of shot peening, is investigated using two-dimensional finite element analysis. The cohesive zone model, which takes into account the damage evolution under cyclic load, is adopted in the finite element analysis to simulate the potential fracture surfaces. The effects of shot peening on the fatigue crack growth and the relaxation of residual stress under cyclic load are studied. It is shown that the residual stress retards the fatigue crack propagation and the retardation effect depends not only on the shot peening intensity but also on the cyclic load amplitude. The residual stress relaxes nonlinearly as the load cycles increase.

Inhibition mechanism of five 1-(2-aminoethyl)-2-alkyl-imidazoline derivatives for carbon steel against CO2 corrosion was studied by molecular modeling. Molecular reactivity derived from quantum chemical calculation is insensitive to alkyl length. Inhibitor molecules can be adsorbed preferentially on metal surface with imidazoline ring attached on the surface. And with increase of alkyl length, interaction between inhibitor molecule and metal surface is enhanced to enable more stable adsorption of inhibitor molecules, which will form more compact self-assembly membrane with higher inhibition efficiency. The efficiency order of the inhibitors obtained by theoretical analysis was verified by experimental results.

The fresh air volume in Temperature and Humidity Independent Control of Air-conditioning System(THIC) of a typical office was comfirmed, under the premise of adopting the refrigeration dehumidifying fresh air unit(7°C/12°C). By detailed calculating the space moisture load and the fresh air volume required for dehumidification in 120 selected major cities in China, it can be inferred that the minimum fresh air volume required for dehumidification in THIC is mainly determined by the local outdoor air moisture and the outdoor wind speed; Then the mathematical fitting software Matlab was used to fit the three parameters, and a simplified formula for calculating the minimum per capita fresh air volume required for dehumidification was obtained; And the indoor relative humidity was simulated by the numerical software Airpak and the results by using the formula data and the data for hygiene were compared to verify the relibility of the simplified formula.

Corrosion inhibiting performance of 1-hydroxyethyl-2-heptadecylimidazoline (A) and 1-aminoethyl-2-heptadecylimidazoline (B) for mild steel was evaluated by combination of quantum chemistry calculation, molecular mechanics, and molecular dynamics simulation. The calculated results by quantum chemistry method demonstrated that frontier orbitals of A and B molecules are mainly located on imidazoline rings, and molecule B possesses higher reactivity than molecule A. The calculated results by molecular mechanics and molecular dynamics simulation presented that these two inhibitor molecules could form dense and high-coverage membranes to prevent diffusion of reactive corrosive species to metal surface. Furthermore, the adsorption energy, cohesive energy, and adsorption angle demonstrated that the binding affinity and stability of B membrane was remarkably greater than that of A, which indicated that B had better inhibition performance in CO2 corrosion. The calculated results were well accorded with previous reported experimental results. These researches implied that molecular modeling might be an effective approach to assess inhibition performance, which has potential application in design of new inhibitors.

Shot peening has been widely applied in industrial design to improve fatigue durability of high loaded machine components. The compressive residual stress induced by shot peening is in general assumed to be responsible for the improvement of material fatigue strength. In the present work a cyclic cohesive zone model is extended to analyze three-dimensional fatigue crack growth in shot-peened specimens. Fatigue crack growth behaviors in both unpeened and peened specimens are investigated using 3D finite element analysis. The parameters of the cohesive zone model have been identified in 2D unpeened specimens and are applied to predict peened specimens directly. The results indicate that shot peening strongly affects crack initiation time and crack profiles, but has little effect on crack propagation rate. It implies that the shot peening will hardly change Paris’ law used for the damage tolerant design.

A facile integrated platform for proteome profiling was established, in which native proteins were online denatured and reduced within a heater, digested with an immobilized trypsin microreactor, and analyzed by microflow reversed-phase liquid chromatography with electrospray ionization tandem mass spectrometry (microRPLC-ESI-MS/MS). In comparison to the traditional off-line urea denaturation protocol, even more unique peptides were obtained by online heating in triplicate (14 +/- 2 vs 11 +/- 2 for myoglobin and 16 vs 12 +/- 1 for BSA) within a significantly shortened pretreatment time of approximately 3.5 min (including 1 min of thermal denaturation and reduction and approximately 2.5 min of microreactor digestion). Moreover, proteins with concentrations ranging from 50 ng/mL (approximately 6 fmol) to 1 mg/mL (approximately 120 pmol) were positively identified by the online system. Such a platform was further successfully applied for analyzing the soluble fraction of mouse liver extract. Of all the 367 proteins identified from samples pretreated by the urea protocol and online heating, approximately 40% were overlapped, showing the partial complementation of both approaches. All these results demonstrate that the online integrated platform is of great promise for high-throughput proteome profiling and improved identification capacity for low-abundance proteins with a minute sample amount.

Ab initio molecular dynamics simulations reveal that an excess electron (EE) can be more efficiently localized as a cavity-shaped state in aqueous glucose solution (AGS) than in water. Compared with that (∼1.5 ps) in water, the localization time is shortened by ∼0.7-1.2 ps in three AGSs (0.56, 1.12, and 2.87 M). Although the radii of gyration of the solvated EEs are all close to 2.6 A in the four solutions, the solvated EE cavities in the AGSs become more compact and can localize ∼80% of an EE, which is considerably larger than that (∼40-60% and occasionally ∼80%) in water. These observations are attributed to a modification of the hydrogen-bonded network by the introduction of glucose molecules into water. The water acts as a promoter and stabilizer, by forming voids around glucose molecules and, in this fashion, favoring the localization of an EE with high efficiency. This study provides important information about EEs in physiological AGSs and suggests a new strategy to efficiently localize an EE in a stable cavity for further exploration of biological function.

We report an ab initio molecular dynamics simulation study of the solvation and dynamics of an excess electron in liquid acetonitrile (ACN). Four families of states are observed: a diffusely solvated state and three ACN core-localized states with monomer core, quasi-dimer (π*-Rydberg mode) core, and dual-core/dimer core (a coupled dual-core). These core localized states cannot be simply described as the corresponding anions because only a part of the excess electron resides in the core molecule(s). The quasi-dimer core state actually is a mixture that features cooperative excess electron capture by the π* and Rydberg orbitals of two ACNs. Well-defined dimer anion and solvated electron cavity were not observed in the 5-10 ps simulations, which may be attributed to slow dynamics of the formation of the dimer anion and difficulty of the formation of a cavity in such a fluxional medium. All of the above observed states have near-IR absorptions and thus can be regarded as the solvated electron states but with different structures, which can interpret the experimentally observed IR band. These states undergo continuous conversions via a combination of long-lasting breathing oscillation and core switching, characterized by highly cooperative oscillations of the electron cloud volume and vertical detachment energy. The quasi-dimer core and diffusely solvated states dominate the time evolution, with the monomer core and dual-core/dimer core states occurring occasionally during the breathing and core switching processes, respectively. All these oscillations and core switchings are governed by a combination of the electron-impacted bending vibration of the core ACN molecule(s) and thermal fluctuations.

Background.Following the two rounds of whole-genome duplication that occurred during deuterostome evolution, a third genome duplication occurred in the lineage of teleost fish and is considered to be responsible for much of the biological diversification within the lineage. GATA2, a member of GATA family of transcription factors, is an important regulator of gene expression in hematopoietic cell in mammals, yet the role of this gene or its putative paralogs in ray-finned fishes remains relatively unknown.Methods.In this study, we attempted to identify GATA2 sequences from the transcriptomes and genomes of multiple teleosts using the bioinformatic tools MrBayes, MEME, and PAML. Following identification, comparative analysis of genome structure, molecular evolution rate, and expression by real-time qPCR were used to predict functional divergence of GATA2 paralogs and their relative transcription in organs of female and male tongue soles (Cynoglossus semilaevis).Results.Two teleost GATA2 genes were identified in the transcriptomes of tongue sole and Japanese flounder (Paralichthysolivaceus). Synteny and phylogenetic analysis confirmed that the two genes likely originated from the teleost-specific genome duplication . Additionally, selection pressure analysis predicted these gene duplicates to have undergone purifying selection and possible divergent new functions. This was supported by differential expression pattern of GATA2a and GATA2b observed in organs of female and male tongue soles.Discussion.Our results indicate that two GATA2 genes originating from the first teleost-specific genome duplication have remained transcriptionally active in some fish species and have likely undergone neofunctionalization. This knowledge provides novel insights into the evolution of the teleost GATA2 genes and constituted important groundwork for further research on the GATA gene family.

Studies on the structure, states, and reactivity of excess electrons (EEs) in biological media are of great significance. Although there is information about EE interaction with desolvated biological molecules, solution effects are hardly explored. In this work, we present an ab initio molecular dynamics simulation study on the interaction and reactivity of an EE with glycine in solution. Our simulations reveal two striking results. Firstly, a pre-solvated EE partially localizes on the negatively charged -COO(-) group of the zwitterionic glycine and the remaining part delocalizes over solvent water molecules, forming an anion-centered quasi-localized structure, due to relative alignment of the lowest unoccupied molecular orbital energy levels of potential sites for EE residence in the aqueous solution. Secondly, after a period of anion-centered localization of an EE, the zwitterionic glycine is induced to spontaneously fragment through the cleavage of the N-Cα bond, losing ammonia (deamination), and leaving a ˙CH2-COO(-) anion radical, in good agreement with experimental observations. Introduction of the same groups (-COO(-) or -NH3(+)) in the side chain (taking lysine and aspartic acid as examples) can affect EE localization, with the fragmentation of the backbone part of these amino acids dependent on the properties of the side chain groups. These findings provide insights into EE interaction mechanisms with the backbone parts of amino acids and low energy EE induced fragmentation of amino acids and even peptides and proteins.

The GATA family of transcription factors is characterized by two zinc finger domains and is involved in different cellular processes. GATA4 is a highly conserved transcription factor that regulates embryonic morphogenesis and cellular differentiation. GATA4 in vertebrates regulates its target genes to influence genital ridge differentiation. In this study, the GATA4 from tongue sole (Cynoglossus semilaevis) was characterized to understand the function of this transcription factor in sex differentiation. The full-length cDNA of C. semilaevis GATA4 comprised 2031bp, encoding a predicted polypeptide consisting of 402 amino acids with two conserved zinc finger domains. Phylogenetic, gene structure, and synteny analyses showed that C. semilaevis GATA4 was homologous to tetrapod GATA4. The mRNA transcript of C. semilaevis GATA4 exhibited high expression in the heart, liver, and gonad. GATA4 expression is dimorphic in the male and female gonads. Embryonic development expression profiles revealed the possible involvement of C. semilaevis GATA4 in morphogenesis. In situ hybridization results showed strong GATA4 signals in the spermatogonia and spermatocytes of the testis and in the oogonia, primary oocytes, and secondary oocytes of the ovary. The expression of C. semilaevis GATA4 in the male, pseudomale, and female gonads showed significantly different methylation levels of the two CpG sites (-2738 and -2647) among the three genders. Basing on these results, we speculated that GATA4 plays a potential role in sex differentiation. This study lays the groundwork for further sex control breeding techniques in C. semilaevis.

The production of ethylbenzene from the alkylation of dilute ethylene in fcc off-gases with benzene has been commercialized in China over a newly developed catalyst composed of ZSM-5/ZSM-11 co-crystallized zeolite. The duration of an operation cycle of the commercial catalyst could be as long as 180 days. The conversion of ethylene could attain higher than 95%, while the amount of coke deposited on the catalyst was only about 10 wt.%. Thermogravimetry (TG) was used to study the coking behavior of the catalyst during the alkylation of fcc off-gas with benzene to ethylbenzene. Based on effects of reaction time, reaction temperature, reactants and products on coking during the alkylation process, it is found that the coking rate during the alkylation procedure follows the order: ethylbenzene>ethylene>propylene>benzene for single component, and benzene–ethylene>benzene–propylene for bi-components under the same reaction condition. Furthermore, the coking kinetic equations for benzene–ethylene, benzene–propylene and ethylbenzene were established.

In order to realize the process mechanism that Shewanella oneidensis(S. oneidensis ) reduced uranium(VI), and improve its reduction effect, the reduction mechanisms of uranium with S. oneidensis were studied by FTIR, SEM, EDS. The results show that after the S. oneidensis reduction of U(VI), the cell surface morphology is changed, the gaps and caverns on S. oneidensis surface decrease and more uncrystalmini grains through electron appear, which are binding each other. Much of new crystal structures were generated on the surface of cell. K and PO4 3+ were involved in the process of U(VI) reduction. FT IR spectra analysis indicated that the main groups of S. oneidensis were association of hydroxyl, phenolic hydroxyl, amidogent, halogenated hydrocarbon, carboxyl in the process of U (VI) reduction.

Hierarchical imprinting was developed to prepare the protein imprinted materials, as the artificial antibody, for the selective depletion of HSA from the human serum proteome. Porcine serum albumin (PSA) was employed as the dummy template for the fabrication of the recognition sites. To demonstrate the advantages of the hierarchical imprinting, molecularly imprinted polymers prepared by hierarchical imprinting technique (h-MIPs) were compared with those obtained by bulk imprinting (b-MIPs), in terms of the binding capacity, adsorption kinetics, selectivity and synthesis reproducibility. The binding capacity of h-MIPs could reach 12 mg g(-1). And saturation binding could be reached in less than 20 min for the h-MIPs. In the protein mixture, h-MIPs exhibit excellent selectivity for PSA, with imprinting factors as about 3.6, much higher than those for non-template proteins. For the proteomic application, the identified protein group number in serum treated by h-MIPs was increased to 422, which is 21% higher than that obtained from the original serum, meanwhile the identified protein group number for the Albumin Removal kit was only 376. The results demonstrate that protein imprinted polymers prepared by hierarchical imprinting technique, might become the artificial antibodies for the selective depletion of high abundance proteins in proteome study.

We present an ab initio molecular dynamics simulation study of a CH3CN-(H2O)40 cluster with an excess electron (EE) injected vertically in this work. Instead of surface bound or internally solvated electron, a hydrated CH3CN(-) is first formed as the CN transient after geometrical relaxation. The driving forces for the formation of CH3CN(-) are bending vibration of ∠CCN angle, which initiates transfer of an extra charge to the CH3CN LUMO, and hydration effect of the immediate water molecules, which plays a stabilizing role. Solvent thermal fluctuation can lead to different resonances (the quasi-C2-resonance versus quasi-N-resonance) from the CN transient and further cause the hydrated CH3CN(-) system to evolve via two distinctly different pathways featuring spontaneous proton transfer to the central C and N sites, producing two different protonation products, respectively. The solvent thermal fluctuation induced formation of hydrogen bonding with the corresponding sites (C2 versus N) is responsible for the quasi-resonances and interconversion between three resonant structures and further proton transfers featuring spontaneous transfer of a proton to C2 or to N from its interacting water molecule. The duration of CH3CN(-) for either of the two proton transfer processes is less than 200 fs. On the basis of experimental ESR results in which only the CH3CHN radical was found and present theoretical calculations, it is suggested that the trans-CH3CNH radical can be further converted to the CH3CHN radical via a water-mediated hydrogen atom transfer path.

Astragaloside is one of the most common traditional Chinese medicines and is derived from Astragalus membranaceus. Astragaloside IV (AsIV) is a monomer located in an extract of astragaloside. The current study investigated the protective effects of AsIV against hydrogen peroxide (H2O2)-induced injury in cardiocytes and elucidated the mechanisms responsible for this protective effect. Cultured neonatal rat cardiocytes were divided into five experimental groups as follows: i) Dimethyl sulfoxide; ii) H2O2; iii) AsIV+H2O2; iv) AsIV+H2O2+5-hydroxydecanoate (5-HD); and v) nicorandil+H2O2. Cardiocyte survival was analyzed using an MTT assay. Lactate dehydrogenase (LDH) release was also assessed to evaluate the viability of the cells. Intracellular reactive oxygen species (ROS) were measured by 2,7-dichlorodihydrofluorescein diacetate staining. The apoptotic rate was measured by flow cytometry. Mitochondrial membrane potential (ΔΨm) and intracellular calcium were observed using a laser confocal microscopy system. The results indicated that AsIV promoted the survival of cardiocytes (P

In Lepidoptera, choosing the right site for egg laying is particularly important, because the small larvae cannot forage for alternate host plants easily. Some secondary compounds of plants have the ability to deter oviposition behaviors of insects. Rhodojaponin-III, a botanical compound, has been reported to have intense deterring-oviposition activity against many insects, which have important implications for agricultural pest management. This study provided evidence for elucidating the perception mechanism underlying Rhodojaponin-III as oviposition deterrent. In this study, the antennas of moths could not elicit notable electroantennogram responses to Rhodojaponin-III, which suggested the Rhodojaponin-III could not exert effects like those volatile compounds. The results of physiological experiments confirmed the Rhodojaponin-III could produce the oviposition deterrence effect against moths without depending on antennas, while the physical contact was essential for perceiving the compound, which suggested that the sensilla on tarsus and ovipositor could be chemoreceptor for Rhodojaponin-III. Therefore, these sensilla were investigated by scanning electron microscopy to explore their potential functions in detecting Rhodojaponin-III. This study highlighted the contacting mechanism in deterring oviposition behaviors of moths by Rhodojaponin-III and provided new insight for development of contact-based pest management.

Fine particles about 20 nm in average diameter of Fe1−xNix (x=0.10–0.85) alloys prepared by evaporation in nitrogen atmosphere were studied using Mossbauer technique, x-ray diffraction, and magnetic measurement. Their different phases were identified, and their hyperfine field distribution, specific saturation magnetization, remnant magnetization, and coercivity were determined. The fine particles show some properties, which are sensitive to the Ni content x and different from those of corresponding bulk alloys. The results suggest that the fine particles may be useful from an applied viewpoint.

The catalytic performance of Fe/Si‐2 and Fe–Mn/Si‐2 catalysts for conversion of C2H6 with CO2 to C2H4 was examined in a continuous‐flow and fixed‐bed reactor. The results show that the Fe–Mn/Si‐2 catalyst exhibits much better reaction activity and selectivity to C2H4 than those of the Fe/Si‐2 catalyst. Furthermore, the coking–decoking behaviors of these catalysts were studied through TG. The catalytic performances of the catalysts after regeneration for conversion of C2H6 or dilute C2H6 in FCC off‐gas with CO2 to C2H4 were also examined. The results show that both activity and selectivity of the Fe–Mn/Si‐2 catalyst after regeneration reached the same level as those of the fresh catalyst, whereas it is difficult for the Fe/Si‐2 catalyst to refresh its reaction behavior after regeneration.