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The composition is a significant issue for corrosion resistance of metallic materials. To reveal the correlation of corrosion behavior between multiprinciple alloys and their constituents, a series of single-phase equiatomic alloys of CoCrNi, CoCrNiFe and CoCrNiFeMn was fabricated. The electrochemical and scanning electron microscope results demonstrated that corrosion resistance of the equiatomic alloys in 0.1 M NaCl solution is located in the range but not the average value of their constituents. X-ray photoelectron spectroscopy analysis indicated that the protective performance of passive film is mainly determined by the constituent with the highest corrosion resistance and the breakdown of passive film is mainly dominated by the elements with the highest corrosion rate. Our findings can guide the materials design of multiprinciple alloys with expected corrosion performance.

Finite element simulations for metal powder compaction of a clutch plate were performed to examine the stresses during compaction, unloading, and ejection. To describe the mechanical behavior of compacted green body, a modified density-dependent Drucker–Prager Cap model was utilized to predict the stress and density distribution of the compacted clutch plate during loading and ejection stages. The results indicate that maximum tensile principal stress was a main driving force for the tensile crack initiation during ejection stage, and shear stress may be another driving force in both compaction and ejection stages for shear crack initiation. There were peak value of the stresses during ejection stage, and the stresses are in compressive state only during compaction stage. Therefore, the tensile crack initiation is not possible during compaction except shear crack. Hoop stress in the clutch plate is of less contribution to the crack initiation during compaction, unloading and ejection. Study of criteria of the crack initiation and fracture is necessary in order to obtain uniform density and crack-free components in the manufacturing of metal powder compaction.

ABSTRACTStrip tension fluctuation caused by the attenuation of a furnace roller’s surface roughness leads to strip deviation in continuous annealing. After several field experiments and theoretical studies, this work established a model for the surface roughness attenuation of a furnace roller during continuous annealing. The model is fully integrated with the equipment and process features of a continuous annealing unit. With the stability of strip travelling as the control object and the absence of strip deviation and buckling as constraints, a tension compensation technique of continuous annealing was developed, and a related theory was applied to production and practise. Software was also developed for predicting the roughness attenuation of a furnace roller during continuous annealing and determining tension compensation for a specific process of the unit. Integrated optimisation of tension parameters in all processes of continuous annealing was also achieved.

Strip tension fluctuation caused by the attenuation of a furnace roller’s surface roughness leads to strip deviation in continuous annealing. After several field experiments and theoretical studies, this work established a model for the surface roughness attenuation of a furnace roller during continuous annealing. The model is fully integrated with the equipment and process features of a continuous annealing unit. With the stability of strip travelling as the control object and the absence of strip deviation and buckling as constraints, a tension compensation technique of continuous annealing was developed, and a related theory was applied to production and practise. Software was also developed for predicting the roughness attenuation of a furnace roller during continuous annealing and determining tension compensation for a specific process of the unit. Integrated optimisation of tension parameters in all processes of continuous annealing was also achieved.

Several problems, such as strip deviation and buckling, are encountered in the continuous annealing process. In this study, equipment and process features of continuous annealing, as well as the advantages and disadvantages of single taper roller and double taper roller in the prevention and treatment of the buckling and strip deviation were considered. Basing on a number of field experiments and theoretical studies, a new set of furnace roller profile curve was proposed and a set of optimisation model suitable for furnace roller was established, with travelling stability of the strip as the objective function. Test results of field production showed that the strip exhibited high speed and stability after optimisation, and the service cycle of the furnace roller was considerably improved. The results of this study provide an important economic benefit for the site and are valuable for further popularisation and application.

The previous tension setting for the continuous annealing process (CAP) is not comprehensive; that is, it does not synthetically consider the factors of strip deviation, buckling, flatness and width narrowing. To address this issue, this study integrated the mechanical and technological characteristics of a continuous annealing line to present a comprehensive control index that can characterise the stability of a travelling strip. Meanwhile, strip deviation, buckling, strip shape and width narrowing were regarded as constraints in each process section. A comprehensive optimisation technique for the tension setting during CAP was then established, and a related theory was applied during production. In addition, a comprehensive tension setting optimisation software was developed for a cold rolled strip during continuous annealing, and the comprehensive optimisation of the tension parameters in each process section was realised. A practical implementation proves that the developed technique exhibits good application effects and considerable application values.

ABSTRACTThe previous tension setting for the continuous annealing process (CAP) is not comprehensive; that is, it does not synthetically consider the factors of strip deviation, buckling, flatness and width narrowing. To address this issue, this study integrated the mechanical and technological characteristics of a continuous annealing line to present a comprehensive control index that can characterise the stability of a travelling strip. Meanwhile, strip deviation, buckling, strip shape and width narrowing were regarded as constraints in each process section. A comprehensive optimisation technique for the tension setting during CAP was then established, and a related theory was applied during production. In addition, a comprehensive tension setting optimisation software was developed for a cold rolled strip during continuous annealing, and the comprehensive optimisation of the tension parameters in each process section was realised. A practical implementation proves that the developed technique exhibits good application effects and considerable application values.

ABSTRACTSeveral problems, such as strip deviation and buckling, are encountered in the continuous annealing process. In this study, equipment and process features of continuous annealing, as well as the advantages and disadvantages of single taper roller and double taper roller in the prevention and treatment of the buckling and strip deviation were considered. Basing on a number of field experiments and theoretical studies, a new set of furnace roller profile curve was proposed and a set of optimisation model suitable for furnace roller was established, with travelling stability of the strip as the objective function. Test results of field production showed that the strip exhibited high speed and stability after optimisation, and the service cycle of the furnace roller was considerably improved. The results of this study provide an important economic benefit for the site and are valuable for further popularisation and application.

ABSTRACTIn order to improve the wear resistance of carburised M50NiL steel, the surface layer was deposited with Ti coating by magnetron sputtering and then plasma nitrided for 2 h with hollow cathode equipment. The influence of nitriding temperature (750, 800 and 850°C) on microstructure and mechanical properties of the coating were investigated. Results show that the coating of specimen 750 containing Ti-based-nitrides possesses higher nanohardness (13.769 ± 0.738 GPa) than the carburised layer (7.695 ± 0.338 GPa) and the load bearing capacity reaches 18 N due to the supporting carburised layer. The friction coefficient and wear rate of the specimen 750 decrease 23.1 and 72.2%, respectively, compared with the carburised specimen. The hardness and wear performance of the specimen 800 and 850 were underestimated by traditional test criterion because a loose and porous a′C(N)layer was formed on the surface due to sputtering effect of steel hollow cathode.

In order to improve the wear resistance of carburised M50NiL steel, the surface layer was deposited with Ti coating by magnetron sputtering and then plasma nitrided for 2 h with hollow cathode equipment. The influence of nitriding temperature (750, 800 and 850°C) on microstructure and mechanical properties of the coating were investigated. Results show that the coating of specimen 750 containing Ti-based-nitrides possesses higher nanohardness (13.769?±?0.738 GPa) than the carburised layer (7.695?±?0.338 GPa) and the load bearing capacity reaches 18 N due to the supporting carburised layer. The friction coefficient and wear rate of the specimen 750 decrease 23.1 and 72.2%, respectively, compared with the carburised specimen. The hardness and wear performance of the specimen 800 and 850 were underestimated by traditional test criterion because a loose and porous a'C(N)layer was formed on the surface due to sputtering effect of steel hollow cathode.

This paper considers the equipment and technological characteristics of continuous annealing process (CAP) to solve the issue of strip buckling. It analyses the mechanism of hot buckling and transverse compressive stresses from internal and external forces. A basic description of strip buckling is given together with a new concept of a buckling index. The critical buckling condition is presented, and the model of strip buckling index in the CAP is proposed. The distribution of strip buckling index in different sections of the process is analysed quantitatively along with the influence of incoming strip shape, transverse temperature difference, roller profile, friction coefficient, set tension and strip processing speed on the strip hot buckling index in CAP. Results show that with the influence of thermal stress, the transverse compressive stress that affects the middle part of the strip is largest in the heating section, which is also where hot buckling occurs most easily; centripetal force is dominant in the soaking and slow cooling sections, and in these sections buckling occurs at the roller shoulder. In different sections, the strip buckling index distribution differs, whereas the influence of other parameters on buckling index remains similar.

This paper considers the equipment and technological characteristics of continuous annealing process (CAP) to solve the issue of strip buckling. It analyses the mechanism of hot buckling and transverse compressive stresses from internal and external forces. A basic description of strip buckling is given together with a new concept of a buckling index. The critical buckling condition is presented, and the model of strip buckling index in the CAP is proposed. The distribution of strip buckling index in different sections of the process is analysed quantitatively along with the influence of incoming strip shape, transverse temperature difference, roller profile, friction coefficient, set tension and strip processing speed on the strip hot buckling index in CAP. Results show that with the influence of thermal stress, the transverse compressive stress that affects the middle part of the strip is largest in the heating section, which is also where hot buckling occurs most easily; centripetal force is dominant in the soaking and slow cooling sections, and in these sections buckling occurs at the roller shoulder. In different sections, the strip buckling index distribution differs, whereas the influence of other parameters on buckling index remains similar.

Prohormone convertase 1/3 is a serine endoprotease belonging to the subtilisin-like proprotein convertase family that is encoded by the proprotein convertase subtilisin/kexin type 1(PCSK1) gene, and its major function is the processing and bioactivation of the proproteins of many kinds of neuroendocrine hormones, including insulin, cholecystokinin, and adrenocorticotropic hormone. The results of our previous genomewide association study indicated that the PCSK1gene might be an important candidate gene for fatness traits in chickens. The objectives of this study were to investigate the tissue expression profiles of PCSK1gene and to identify functional variants associated with fatness and growth traits in the chicken. The results indicated that PCSK1mRNA was widely expressed in various tissues, especially neuroendocrine and intestinal tissues. Of these 2 tissue types, PCSK1mRNA expression in lean males was significantly higher than in fat males. A SNP in the 3′ untranslated region of PCSK1(c.*900G > A) was identified. Association analysis in the Arbor Acres commercial broiler population and Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF) population showed that the SNP c.*900G > A was associated with abdominal fat weight, abdominal fat percentage, BW, metatarsus length, and metatarsal circumference. In the 5th to 19th generation (G5to G19) of NEAUHLF, the allele frequency of c.*900G > A changed along with selection for abdominal fat content. At G19, allele G of c.*900G > A was predominate in the lean line, whereas allele A was predominate in the fat line. Functional analysis demonstrated that allele A of c.*900G > A reduced mRNA stability and consequently downregulated gene expression. These results suggested that c.*900G > A was a functional SNP for fatness and growth traits in the chicken. The results of this study provide basic molecular information for the role of PCSK1gene in avian growth and development, especially obesity.

Using the electron phase space density (PSD) data measured by Van Allen Probe A from January 2013 to April 2015, we investigate the effects of magnetospheric processes on relativistic electron dynamics in the Earth's outer radiation belt during 50 geomagnetic storms. A statistical study shows that the maximum electron PSDs for various μ(μ =630, 1096, 2290, and 3311 MeV/G) at L*~4.0 after the storm peak have good correlations with storm intensity (cc~0.70). This suggests that the occurrence and magnitude of geomagnetic storms are necessary for relativistic electron enhancements at the inner edge of the outer radiation belt (L* =4.0). For moderate or weak storm events (SYM‐Hmin> ~−100 nT) with weak substorm activity (AEmax< 800 nT) and strong storm events (SYM‐Hmin≤ ~−100 nT) with intense substorms (AEmax≥ 800 nT) during the recovery phase, the maximum electron PSDs for various μat different L*values (L* =4.0, 4.5, and 5.0) are well correlated with storm intensity (cc >0.77). For storm events with intense substorms after the storm peak, relativistic electron enhancements at L* =4.5 and 5.0 are observed. This shows that intense substorms during the storm recovery phase are crucial to relativistic electron enhancements in the heart of the outer radiation belt. Our statistics study suggests that magnetospheric processes during geomagnetic storms have a significant effect on relativistic electron dynamics. The occurrence and magnitude of geomagnetic storms are necessary for relativistic electron enhancements at the inner edge of the outer radiation beltIntense substorms after the storm peak are crucial to relativistic electron enhancements in the heart of the outer radiation beltMagnetospheric processes during geomagnetic storms have a significant effect on relativistic electron dynamics

Using the particle data measured by Van Allen Probe A from October 2012 to March 2016, we investigate in detail the radiation belt seed population and its association with the relativistic electron dynamics during 74 geomagnetic storms. The period of the storm recovery phase was limited to 72 h. The statistical study shows that geomagnetic storms and substorms play important roles in the radiation belt seed population (336 keV electrons) dynamics. Based on the flux changes of 1 MeV electrons before and after the storm peak, these storm events are divided into two groups of “large flux enhancement” and “small flux enhancement.” For large flux enhancement storm events, the correlation coefficients between the peak flux location of the seed population and those of relativistic electrons (592 keV, 1 MeV, 1.8 MeV, and 2.1 MeV) during the storm recovery phase decrease with electron kinetic energy, being 0.92, 0.68, 0.49, and 0.39, respectively. The correlation coefficients between the peak flux of the seed population and those of relativistic electrons are 0.92, 0.81, 0.75, and 0.73. For small flux enhancement storm events, the correlation coefficients between the peak flux location of the seed population and those of relativistic electrons are relatively smaller, while the peak flux of the seed population is well correlated with those of relativistic electrons (correlation coefficients >0.84). It is suggested that during geomagnetic storms there is a good correlation between the seed population and ≤1 MeV electrons and the seed population is important to the relativistic electron dynamics. Geomagnetic storms and substorms play important roles in the radiation belt seed population dynamicsThe radiation belt seed population is well correlated with ≤1 MeV electronsThe radiation belt seed population is important to the relativistic electron dynamics

In this paper, we used the database of the university of Michigan Radio Astronomy Observatory (UMRAO) at three (4.8 GHz, 8.0 GHZ, and 14.5 GHz) radio frequency to analyze the radio light curves by the power spectral analysis method in search of possible periodicity. The analysis results showed that the radio sources display astrophysically meaningful periodicity ranging from 2.2 to 20.8 years in their light curves at the three frequencies. We also calculated the variability parameters and investigated the correlations between the variability parameter and the flux density. For the variability parameters, we found that the parameters at higher frequency are higher than those in the lower frequency. In addition, the variability parameters of BL Lacertae objects are larger than those of flat-spectrum radio quasars. suggesting that they are more variable than flat spectrum radio quasars.

Riboswitches are structural RNA elements that are generally located in the 5′ untranslated region of messenger RNA. During regulation of gene expression, ligand binding to the aptamer domain of a riboswitch triggers a signal to the downstream expression platform. A complete understanding of the structural basis of this mechanism requires the ability to study structural changes over time. Here we use femtosecond X-ray free electron laser (XFEL) pulses to obtain structural measurements from crystals so small that diffusion of a ligand can be timed to initiate a reaction before diffraction. We demonstrate this approach by determining four structures of the adenine riboswitch aptamer domain during the course of a reaction, involving two unbound apo structures, one ligand-bound intermediate, and the final ligand-bound conformation. These structures support a reaction mechanism model with at least four states and illustrate the structural basis of signal transmission. The three-way junction and the P1 switch helix of the two apo conformers are notably different from those in the ligand-bound conformation. Our time-resolved crystallographic measurements with a 10-second delay captured the structure of an intermediate with changes in the binding pocket that accommodate the ligand. With at least a 10-minute delay, the RNA molecules were fully converted to the ligand-bound state, in which the substantial conformational changes resulted in conversion of the space group. Such notable changes in crystallo highlight the important opportunities that micro- and nanocrystals may offer in these and similar time-resolved diffraction studies. Together, these results demonstrate the potential of ‘mix-and-inject’ time-resolved serial crystallography to study biochemically important interactions between biomacromolecules and ligands, including those that involve large conformational changes.

AbstractAs a typical plasma-based optical element that can sustain ultra-high light intensity, plasma density gratings driven by intense laser pulses have been extensively studied for wide applications. Here, we show that the plasma density grating driven by two intersecting driver laser pulses is not only nonuniform in space but also varies over time. Consequently, the probe laser pulse that passes through such a dynamic plasma density grating will be depolarized, that is, its polarization becomes spatially and temporally variable. More importantly, the laser depolarization may spontaneously take place for crossed laser beams if their polarization angles are arranged properly. The laser depolarization by a dynamic plasma density grating may find application in mitigating parametric instabilities in laser-driven inertial confinement fusion.

Castanopsis hystrix A.DC. is one of the most important and multipurpose tree species native to China. 157 open-pollinated families collected from 11 provenances in Guangdong, Guangxi, and Fujian province were used to estimate genetic parameters for height (H), diameter at breast height (DBH), ground diameter (GD), and crown width (CW) for each province and combined three provinces at ages from 3 to 9 years. The variance component was small and non-significant among provenances but was highly significant among families within provenances for H, DBH, GD, and CW. Heritability estimates were significant except for a few traits from Fujian’s provenances. Heritability ranged from 0.20 to 0.57 for H, 0.19 to 0.38 for DBH, 0.21 to 0.55 for GD, and 0.09 to 0.39 for CW. Heritability estimates for H and DBH decreased with increased age for each province and combined three provinces. Significantly high genetic correlations were observed for ageage and trait-trait correlations, indicating that genetic performance at one trait was well correlated with another trait. In total, 22 families and 60 individuals were selected for backward and forward selection based on breeding values.

AbstractThe paper studied the effect of an array of hemispherical substance-units (HSUs) immersed in inviscid and incompressible liquid on resonance frequency of a quartz crystal resonator (QCR) under the thickness-shear mode (TSM) vibrations. A dynamic model of the compound QCR system, consisting of a QCR and HSUs, was established in advance. The frequency equation of the compound QCR system including the liquid-solid coupling was derived subsequently. Numerical results showed the frequency-shift characteristics of the compound system. The obtained results are useful in resonator design and applications.

Studies in mammalian species showed that Krüppel-like factor 2 (KLF2) regulates adipogenesis. However, its role in birds is unclear. The objective of the current study was to explore the expression and function of KLF2in chicken adipogenesis. Results showed that chicken KLF2(Gallus gallus KLF2[gKLF2]) was greatly expressed in abdominal adipose tissue, and its transcripts fluctuated during adipose tissue development. In addition, gKLF2transcripts in abdominal adipose tissue of lean broilers were greater at 1 wk of age but lower at 3, 5, and 8 wk of age than those in fat broilers (P< 0.05). The gKLF2was more greatly expressed in preadipocytes than in mature adipocytes (P< 0.05), and its expression level decreased during the preadipocyte differentiation in vitro (P< 0.05). The functional analysis showed that gKLF2 overexpression inhibited chicken preadipocyte differentiation (P< 0.05), accompanied by the reduced expression of CCAAT/enhancer binding protein α (C/EBPα) and peroxisome proliferator-activated receptor γ (PPARγ) and the elevated expression of GATA binding protein 2 (GATA2). Additionally, the luciferase reporter assays showed that gKLF2 overexpression suppressed the promoter activities of chicken C/EBPαand PPARγ(P< 0.05). In conclusion, our results indicated that gKLF2 inhibits chicken adipogenesis, at least in part, through inhibition of PPARγand C/EBPαexpression.

Apoptosis induction provides a promising strategy for tumor gene therapy. Non-invasive ultrasound is a novel non-virus transfer method. In the field of cancer therapy, it has been found that ultrasound alone or together with microbubble represents an appealing, efficient and novel technique, which could deliver therapeutic gene or drug to specific organs or tissues in a simple and noninvasive way. Moreover, apoptosis induction mediated by the novel ultrasound-targeted microbubble destruction technique is safer and more effective than other methods, inactivating tumor cells, restraining cell proliferation and improving therapeutic effects of gene or chemotherapeutic drugs. In this paper, we reviewed apoptosis induction by ultrasound and microbubble mediated drug delivery and gene therapy in vitro and in vivo.

To explore the physiological characteristics of the pepcgene in transgenic wheat (Triticum aestivum) plants, PEPC activities in various organs of T3 plants were analyzed at Feekes 6.0, Feekes 10.3 and Feekes 11.1, and compared to control, untransformed wheat cultivar Zhoumai 19. Net photosynthetic rates (Pn) in leaves were also measured at the same stages. At Feekes 11.1, both transgenic and control plants were treated with DCDP. Yield traits were surveyed after harvest. The results indicated that Pnand PEPC activity in the flag leaf of transgenic wheat were significantly higher than those of the control at different stages. At Feekes 10.3, Pnreached the highest value at 28.2 µmol m-2s-1and PEPC activity reached the highest value at 104.6 µmol h-1mg-1. Both factors significantly increased by 21% compared to the control at Feekes 11.1. PEPC activity in the flag leaf of transgenic plants was significantly higher than that of non-leaf organs. Pnof transgenic plants was greatly reduced after DCDP treatment. In the flag leaf of transgenic wheat, Pnwas significantly correlated to PEPC activities at 0.01 probability level with a correlation coefficient of 0.8957**. The yield traits of transgenic line 1-27-3, such as 1000-grain weight, single spike weight and harvest index were higher than those of the control. Additionally, the spike weight of 1-27-3 showed an increase of approximately 9.5% compared to the control. These results indicated that the expression of maize (Zea mays) pepcgene was different across various organs of transgenic wheat and across every growth stage. Therefore, we conclude that introducing maize pepc gene into wheat plants can increase their Pnand improve production.

Peroxisome proliferator-activated receptor γ is a master regulator of adipocyte differentiation and function. Expression of PPARγin mammals is regulated by DNA methylation; however, it is currently unknown whether chicken PPARγexpression is regulated by DNA methylation. To enhance our understanding of molecular mechanisms underlying chicken adipose tissue development and adipogenesis, we investigated the promoter methylation status and gene expression of PPARγgene in Northeast Agricultural University broiler lines divergently selected for abdominal fat content (NEAUHLF). Deoxyribonucleic acid methylation was analyzed by bisulfite sequencing method, and mRNA expression was detected by real-time quantitative real time reverse-transcription polymerase chain reaction (RT-PCR). The analyzed region located from –1,175 to –301 bp upstream of the translation start codon ATG contains 6 CpG dinucleotides, which are located at positions –1,014, –796, –625, –548, –435, and –383 bp, respectively. The results revealed that the 3 CpGs at positions –548, –435, and –383 bp showed differential methylation between the lean and fat chicken lines, but the other 3 CpG sites at positions –1,014, –796, and –625 bp did not. PPARγgene promoter methylation in both chicken lines decreased with age, and PPARγpromoter methylation levels were significantly higher in lean than fat broilers at 2 wk of age (79.9 to 64.5%; P< 0.0001), at 3 wk of age (66.7 to 58.3%; P< 0.0001), and at 7 wk of age (50.0 to 42.7%; P= 0.0004). Real-time quantitative RT-PCR analysis showed that, negatively correlated with DNA methylation (Pearson's r= –0.653, P= 0.0057), PPARγexpression was increased with age and significantly lower in lean than fat chicken lines at 2, 3, and 7 wk of age (P< 0.0001). In conclusion, our findings suggest that chicken PPARγis regulated by DNA methylation during adipose tissue development.

This paper experimentally investigates the effects of welding parameters including electrode force, welding current and welding time on the mechanical properties and microstructure of resistance spot welded DP600 joints. The experimental results show that there exists an optimum value for each set of welding parameters that can maximise the mechanical properties and welding nugget size. The welding nugget size is a key factor controlling the mechanical properties of resistance spot welded DP600 joints; there is a relationship among welding nugget size, tensile shear load and failure energy. A larger welding nugget size leads to a greater probability of pullout failure. In addition, welding parameters also affect the microstructure, grain size, crack initiation and microhardness of resistance spot welded DP600 joints.

The article studies on the processing program of Logarithmic spiral internal gears face with features of CNC linear cutting machine which can be easily used in processing complex parts to produce qualified products and to apply non-key surface connection into the production.

This study investigated the ability of the Physiological and Operative Severity Score for Enumeration of Mortality and Morbidity (POSSUM) scoring system to predict postoperative morbidity (complication rate) and compared the ability of POSSUM and four other scoring systems (Portsmouth POSSUM [p-POSSUM], colorectal POSSUM [cr-POSSUM], Association of Coloproctology of Great Britain and Ireland [ACPGBI] and Acute Physiology and Chronic Health Evaluation II [APACHE II]) to predict mortality within 30 days in 1695 patients undergoing surgery for colorectal cancer. Receiver operating characteristic (ROC) curve, Student's t-test and the χ2-test were used to estimate the predictive ability of these scoring systems. The observed complication rate of 38.7% was not significantly different to the rate of 36.3% predicted by the POSSUM scoring system (observed: expected [O: E] ratio 1.07). The observed mortality rate was 3.0%. For predicting mortality, POSSUM had an O: E ratio of 0.37, compared with p-POSSUM O: E ratio 1.00, cr-POSSUM O: E ratio 0.91, APACHE II O: E ratio 0.31 and ACPGBI O: E ratio 1.41. It was concluded that the POSSUM scoring system had high value for predicting the risk of morbidity following colorectal cancer resection. For predicting postoperative mortality, p-POSSUM, cr-POSSUM and ACPGBI were superior to POSSUM and APACHE II, however ROC curve analysis showed that cr-POSSUM and ACPGI discriminated best between survivors and non-survivors, so were more accurate predictors of postoperative mortality than the other three scoring systems.

Classical molecular dynamics simulation was used to investigate the structure, melting and mechanical properties of Au nanowires encapsulated in single-walled carbon nanotubes (SWCNT). A possibility of synthesizing controlled Au nanowires was firstly studied by encapsulating small clusters into CNTs with suitable diameters. The nanowires with multi-shell structure of cylindrical symmetry are predicted as a consequence of spontaneous and confined coalescence of gold clusters. The investigation of melting temperature and behavior of a gold nanowire with multi-shells in a carbon nanotube (CNT) showed that the melting temperature of the enclosed Au nanowire is lower than its bulk counterpart and higher than that observed for free-standing ones. Different from the melting behavior of freestanding Au nanowires, the melting of Au nanowires enclosed in CNTs with tube diameters (D) in the range of 1.08 nm &lt; D &lt; 2.09 nm investigated here was found to initiate from the center layers. Finally, the deformation behavior of the gold-filled single-walled carbon nanotube was simulated under axial compression. The results show that the buckling strength of the Au-filled carbon nanotube is increased compared with that of a hollow tube, and is similar to the case of filling with gases or fullerenes. The interactions between filling elements and the carbon wall help restrain the collapse of the tube. With Au-filling, the filled tube experiences an elastic-inelastic transition, somewhat like the behavior of metals, which is different from the cases when it is filled with gases or fullerenes, particularly for low filling density.

AbstractVegetation and rainfall are two important factors affecting soil erosion and the resulting nutrients loss on the Chinese Loess Plateau. Field experiments under simulated rainfall condition were conducted to investigate the effect of rainfall intensity and vegetation (Caragana korshinskii) cover on soil loss, sediment-associated nitrogen (N) and phosphorus (P) loss, and particle size distribution (PSD) of the eroded sediment. Treatments included three rainfall intensities (60, 100, and 140 mm h−1[2.364, 3.94, and 5.516 in hr−1]) with each producing 60 min of rainfall and three plots (0%, 30%, and 80%) with the same gradient of 15°. The results showed that vegetation cover, rainfall intensity, and their interaction all had significant effect on sediment and the associated N and P loss. In general, higher rainfall intensity and lower coverage produced higher sediment and consequently higher nutrient loss but led to a lower enrichment ratio for N (ERN) in sediments. Vegetation cover had no marked effect on enrichment ratio of P (ERP). A strong positive linear relation was observed between soil loss and N and P loss. The eroded sediment contained more fine particles (clay and silt, < 20 μm [7.874 × 10-4in]) compared to the original surface soil. Under the same cover condition, the percentage of clay significantly decreased with increasing rainfall intensity (p< 0.05). The ERNand ERPwere positively correlated with ER clay. This suggested that the clay fraction (<2 μm [7.874 × 10-5in]) was preferentially eroded and that N and P were mainly adsorbed onto or contained within this particle fraction.

It is well known that singularities are inherent to parallel manipulators and have serious influence on their properties. It is desired that the motion uncertainty caused by the singularity should be avoided in the design and operation stages. The singularity distribution hypersurface shows the relations among the pose components at the singular points, but it is difficult to be utilized in predicting the motion certainty through checking and controlling the lengths of input parameters. In this article, taking a 3-RPR parallel manipulator as an example, and considering the clearances existing in the joints and the deformations of the input actuating cylinders under external loads, the maximal singularity-free distribution of input parameters is investigated. While the input parameters are located within the space enveloped by the maximal singularity-free distribution surfaces, the manipulator can bear the required external loads and give out a certain motion at the neighbourhood of singular points. Based on this kind of the maximal singularity-free distribution of input parameters, the singularity can be avoided both in the early design stage by assigning the input parameters into a suitable region and in the operation state through controlling and monitoring the values of the input parameters.

The dwarf-male-sterilewheat is unique to China and has been improved by introducing good germplasm. In order to clear the subunits background of Dwarf-Male-Sterilewheat, sodium dodecyl sulphate polyacrylamide-gel electrophoresis (SDS-PAGE) was used to detect the high and low molecular weight glutenin subunits (HMW-GS and LMW-GS) compositions in BC1F1, F2 and F3 generations from Dwarf-Male-Sterilewheat. Twenty-five alleles and 49 HMW-GS compositions at the Glu-1loci were detected in different generations. Null and subunit 1 were mainly existed at Glu-A1, and 7 + 8 and 7 + 9 were primarily detected at Glu-B1in different generations. Subunit combination 5 + 10 mainly appeared in BC1F1, while 2 + 12 major presented in F2 and F3 generations. HMW-GS compositions null, 7 + 8, 5 + 10 and null, 7 + 9, 5 + 10 showed higher frequencies than other banding patterns, followed by null, 14 + 15, 5 + 10 and null, 7 + 9, 2 + 12 combinations. In addition, some rare subunit combinations such as 14 + 15, 13 + 16, 17 + 18, 4 + 12, 2 + 10 and 5 + 12 were found in different generations. Eighteen alleles and 51 LMW-GS compositions at Glu-3loci were found in different generations. Glu-A3a and Glu-B3d showed higher frequencies than others among three generations. There were mainly a, b, c alleles at Glu-D3. Thirty, 31 and 14 different combinations were detected in BC1F1, F2 and F3 populations, respectively. There were some good combinations such as A3d/ B3h, A3d/ B3d/ D3a, A3b/ B3b/ D3a, A3a/ B3d/ D3a for different quality characteristics. So some desirable subunit combinations could be selected from different generations and new cultivars with good quality under distinct subunits background should be bred from Dwarf-Male-Sterilewheat in future.

A new Mnbased Heusler alloy Mn2CuAl has been synthesized by the meltspinning method. It has an ordered bcc structure and is a ferrimagnet with a saturation moment of 1.44 µBf.u. at 5 K. The magnetization mainly comes from the contributions of the antiparallel aligned Mn spin moments. A compensation point is observed at 630 K, indicating the antiferromagnetism between the two Mn sublattices. The Curie temperature of the ribbons is 690 K. When heated to 740 K, the Mn2CuAl ribbons completely decompose to a mixture of a tetragonal phase and a Cu9Al4phase.

AbstractThe transient thermal process of a thin-wall beam with CO2Gas Metal Arc Welding (GMAW) is analyzed by Finite Element Analysis Method (FEA). The thermal input is simplified as transient section body heat sources and loaded as its actual sequence in the analysis. The transient temperature field obtained can represent the basic characteristics of the real welding process and can be used as the foundation of thermal elastic-plastic analysis. Based on the temperature field, thermal elastic-plastic FEA is performed on the thin-wall beam. The distribution and change of the welding deformation, stress and strain are obtained and compared with the experiment results. Also an improvement can be presented on the inherent strain method. Using the inherent strain method, the welding deformation of the thin-wall beam is calculated. The temperature loading method is developed to load the variable inherent strain value expediently. The loading of inherent strain value on spatial welding line that is unparallel to the global coordinate axis is achieved with the application of element coordinate system. Comparison with the experiment results shows that both the thermal-elastic-plastic analysis and inherent strain analysis method can be used to predict the welding deformation effectively, the results calculated by both the thermal-elastic-plastic analysis and inherent strain analysis are close to the test measure results.

ABSTRACTPerformance of an improved shock absorber designed for absorbing and isolating the oil test pipe vibration is researched in this paper. 3D finite element model is established for the analysis of the shock absorber system accurately by the FEA software ANSYS/LS-DYNA. Numerical simulations show that the effect of the shock absorber can be greatly improved by optimizing the plastic material parameter. In the practice petroleum well test, the new designed shock absorber showed good shock absorption effect and no damage on the detecting instruments was observed even after ten times loading.

A new method of synthesis a series of pure dialkylbenzene sulfonates is described. The benzene ring carries a major alkyl substituent, consisting of a linear chain of sixteen carbon atoms long, and one additional methyl group. Products are charactered by EI-MS and 1H NMR. Experimental investigations have been conducted to explore the interfacial tension behavior of crude oil with dialkylbenzenesulfonates. The effects of various parameters such as surfactant concentration, salinity concentration on the interfacial tension of crude oil-water were investigated in detail. The transient low interfacial tensions in crude oil/alkali system were caused by the synergistic effects between surfactant and the active species generated at interface, but surfactant molecules plays the dominant role at equilibrium.

Insulin-like growth factor binding protein 2 regulates a broad spectrum of biological activities involved in growth, development, and differentiation. The current study was designed to investigate the associations of IGFBP2 gene polymorphisms with chicken growth and body composition traits. The Northeast Agricultural University Resource Population (NEAURP) was established by crossing broiler sires, derived from lines at Northeast Agricultural University, that were divergently selected for abdominal fat, with Baier layer dams, a Chinese local breed. The F1birds were inter-crossed to produce an F2population. Body weight and body composition traits were measured in the NEAURP. The PCR primers for the intron 2 region of IGFBP2 were designed based on chicken genomic sequence. Nucleotide polymorphisms between parental lines were detected by DNA sequencing. A C/T SNP in intron 2 was detected, and PCR-RFLP methods were then developed to genotype the F2individuals. The results showed that the IGFBP2 SNP was associated with multiple traits, including BW, metatarsus length, shank length, femur length, shank weight, femur weight, metatarsus claw weight, and abdominal fat weight in the 1,028 NEAURP F2individuals. This research suggests that IGFBP2 or a tightly linked gene has broad effects on growth and development in the chicken.

Global proteome of the antibiotic-production strain 103 and the nonantibiotic-production mutant cnn1 were directly analyzed using 2D LC−MS/MS. A total of 726 and 809 proteins have been identified, respectively. Physical and chemical characterization, subcellular location and functional classification of the global protein were carried out. By searching the key enzymes of several probable antibiotic biosynthesis pathways in the identified proteins of strain 103, only polyketide synthase was found, which suggested that Maituolaimysin be synthesized through polyketide pathway. The same searching result was obtained in strain cnn1, which confirmed the conclusion drew from strain 103. Other proteins associated with the polyketide pathway of the two strains were searched according to the protein classification scheme of Streptomyces coelicolor (available at http://www.sanger.ac.uk/Projects/S_coelicolor/) and most of them were found. The activity inhibition of beta-ketoacyl ACP synthase, a key enzyme in the polyketide pathway, directly resulted in the decrease of Maituolaimysin production, which proved the conclusion obtained in the proteomic research. Keywords: proteomics • 2D LC−MS/MS • Streptomyces luteogriseus • polyketide pathway • microlide

Background: Glucocorticoids acting as anti-inflammatory or immunosuppressive drugs have been shown to exert most of their effects genomically. Recent findings suggest that non-genomic activity might be relatively more important in mediating the therapeutic effects of high-dose pulsed glucocorticoid. However, few non-genomic anti-inflammatory effects were reported, much less non-genomic mechanisms.

Zeolite RUB-41, framework type code RRO, having a new framework structure has been synthesized as a calcination product using a layered silicate, RUB-39, as precursor. The precursor was obtained from hydrothermal synthesis using dimethyldipropylammonium hydroxide as structure directing agent. RUB-41, 18SiO2 per unit cell, crystallizes in the monoclinic space group P2/c with a = 7.345(1) Å, b = 8.724(1) Å, c = 17.125(1) Å, and β = 114.2(1)°. The material has a 2-dimensional channel system with intersecting 8- and 10-membered ring pores. The pore openings determined from structure analysis are 5.8 Å × 4.1 Å (8MR) and 5.9 Å × 4.1 Å (10MR). The surface area determined from nitrogen adsorption experiments is 510 m²/g and the pore space is accessible for linear molecules. The material shows high sorption interaction for C4 alkenes and excludes i-butane from the pore system.

The slow growth characteristics of a condensing ethanol sessile drop on a quartz substrate were studied experimentally. Using interference microscopy measurements of the transient liquid film profile (curvature) to obtain the pressure field and a Kelvin−Clapeyron model of interfacial mass flux to obtain the interfacial temperature difference, changes in the apparent contact angle were related to interfacial subcooling and, therefore, adsorption. We found that while the radius of curvature of the growing drop increased linearly with time, the apparent contact angle remained the same during slow growth at a constant condensation heat flux. The radii of curvature and the apparent contact angles at different axial locations were measured and compared. The results demonstrated that the curvature, the contact angle, the interfacial subcooling, the interfacial mass flux, the spreading velocity, and adsorption are coupled at the moving contact line. Motion and the apparent contact angle are governed by the condensed adsorbed thin film thickness and curvature at the contact line.

Combined acute inhibition of the synthesis of nitric oxide with L-nitroarginine methyl ester (L-NAME) and of prostacycline synthesis with indomethacin predisposes rats to severe renal injury from radiographic contrast media. The reliability of this pharmacological manipulation in the study of radiographic contrast medium induced nephropathy (RCMN) was investigated. Adult male Sprague–Dawley rats were injected with iv L-NAME (10 mg kg-1) and iv indomethacin (10 mg kg-1) 15?min apart and prior to injection of RCM or normal saline (control group). A dose-dependent reduction in renal function was observed after intravascular injection of the high osmolar RCM diatrizoate (Angiografin, 306?mgI ml-1). A significant (p<0.01) increase in serum creatinine (Cr) (from 54.66±8.39 µmol l-1to 171.96±24.49 µmol l-1and from 80.95±6.73 µmol l-1to 204.76±16.73 µmol -1, n=5 per group) was observed 24 h after injection of 6 ml and 8 ml of diatrizoate, respectively. The increase in serum Cr after injection of 8 ml of diatrizoate recovered spontaneously to 80.87±8.70 µmol l-17 days after injection. No significant change in renal function was observed in the control group (n=5) receiving 8 ml kg-1of normal saline or after injection of 4 ml of diatrizoate (serum Cr 69.84±5.5 µmol l-1pre contrast injection and 66.67±13.47 µmol l-124 h post contrast injection, n=5). The increase in serum Cr observed with 6 ml of diatrizoate was significantly higher (p<0.01) than the rise induced by equivolume of the low osmolar non-ionic monomer iopromide (Ultravist, 300 mgI ml-1) (serum CR 68.47±8.39 µmol l-1pre contrast injection and 143.59±32.03 µmol l-124 h post contrast injection, n=5). The calcium channel blocker diltiazem (10 mg kg-1injected intraperitoneally 30 min prior to RCM injection) prevented the rise in serum Cr observed with 6 ml of diatrizoate (serum Cr pre contrast injection 70.31±7.28 µmol-1and 78.21±17.81 µmol-124 h post contrast injection in animals pre-treated with diltiazem, n=5). The protective effect against RCM-induced reduction in renal function was less with lower doses of diltiazem. In conclusion, the animal model used is reliable and reproduced previously established observations in the field of RCMN. The protective effect of a calcium channel blocker at the appropriate dose against RCMN has also been shown. The clinical effectiveness of this class of drugs in preventing RCMN requires further evaluation.

Autoimmune antibodies to beta(2)-glycoprotein I (beta2GPI) have been proposed to be clinically relevant because of their strong association with thrombosis, miscarriage, and thrombocytopenia. By using a homologous recombination approach, beta2GPI-null mice were generated to begin to understand the physiologic and pathologic role of this prominent plasma protein in mammals. When beta2GPI heterozygotes on a 129/Sv/C57BL/6 mixed genetic background were intercrossed, only 8.9% of the resulting 336 offspring possessed both disrupted alleles. These data suggest that beta2GPI plays a beneficial role in implantation and/or fetal development in at least some mouse strains. Although those beta2GPI-null mice that were born appeared to be relatively normal anatomically and histologically, subsequent analysis revealed that they possessed an impaired in vitro ability to generate thrombin relative to wild type mice. Thus, beta2GPI also appears to play an important role in thrombin-mediated coagulation.