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• The effect of different atmospheres on the oxidation behavior of GH4742 is analyzed. • The weight gain for GH4742 oxidized in H 2 O is always higher than that in O 2. • H 2 O contributes to formation of non-protective Ni- and Co-rich oxides in the OOL. • The specific diffusion of Al3+, Co2+ and Ni2+ at elevated temperature is elucidated. The oxidation behavior of Ni-based superalloy GH4742 exposed to water vapor was investigated at 900–1100 °C for 50 h in Ar+20%H 2 O, with Ar+20%O 2 included for comparison. The presence of H 2 O is adverse to formation of continuous Cr 2 O 3 oxide layer but contributes to generation of big voids. Based on this, Ni2+ and Co2+ are more easily to diffuse towards the outermost oxide layer (OOL), forming non-protective Ni- and Co-rich oxides with high proportion. This leads to a higher weight gain in Ar+20%H 2 O than that in Ar+20%O 2. At elevated temperatures, the spallation of oxide scale occurs while the consumption of Cr is reduced in Ar+20%H 2 O, and the contents of Ni- and Co-rich oxides at this moment are reduced in the OOL. The oxidation mechanism was also discussed. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effects of dietary bamboo leaf extract (BLE) on growth performance, meat quality, oxidative stability, and nuclear factor erythroid 2-related factor 2 (Nrf2) related gene expression of breast meat in broilers. A total of 576 one-day-old male Arbor Acres broilers were divided into 6 groups. The control group (CTR) was fed basal diet, while BLE1, BLE2, BLE3, BLE4, and BLE5 were fed basal diet supplemented with 1.0, 2.0, 3.0, 4.0, and 5.0 g BLE per kg feed, respectively. Compared with the CTR group, BLE2 and BLE5 increased average daily feed intake from 1 to 21 D and 22 to 42 D (P< 0.05), BLE1 and BLE2 improved average daily gain (ADG) and feed to gain ratio from 22 to 42 D (P< 0.05). Throughout the trial period, the highest body weight and favorable ADG and feed to gain ratio were observed in the BLE2 group. The drip loss at 24 h and pH at 45 min postmortem of breast meat were linearly improved by BLE supplementation (P< 0.05). Shear force was significantly lower in BLE2 and BLE3 than that in CTR group. Increasing supplementation of BLE linearly improved free radical scavenging capacity and decreased malondialdehyde content of breast meat during 12 D of storage (P< 0.05). Total antioxidant capacity and glutathione peroxidase activity were linearly increased by BLE supplementation (P< 0.05). Compared with the CTR group, the mRNA expression of Nrf2 and glutathione peroxidase in BLE3, BLE4, and BLE5 groups was significantly promoted, and glutathione S-transferase gene expression was increased in BLE2, BLE4, and BLE5 (P< 0.05). The highest (P< 0.05) heme oxygennase-1 gene expression was observed in BLE5. In conclusion, broiler supplemented with BLE improved growth performance and meat quality, BLE supplementation might activate Nrf2 pathway to alleviate lipid oxidation and increase antioxidant capacity of breast meat. The dosage of 2.0 to 3.0 g/kg BLE in broiler diet was recommanded.

A field experiment was conducted at the vegetable production base of Lixiang town in Shenyang city, Liaoning province to study the effects of dicyandiamide (DCD) application on the accumulation and leaching risk of soil nitrate. The results showed that applying DCD significantly decreased the amount of soil NO3--N in the 0-10cm and 10-20cm soil layers compared to without DCD addition (P &lt; 0.01). However, the difference was not significant in the 20-40cm (P > 0.05). These results indicated that the application of DCD reduced the leaching risk of soil nitrate from topsoil to subsoil. At the 28d of fertilizer application, the amount of soil NO3--N was higher in the NP+M, NP+M+2%DCD and NP+M+5%DCD treatments than in the M, M+2%DCD and M+5%DCD treatments, suggesting that the combined application of chemical fertilizer and organic manure weakened inhibiting effect of DCD on the amount of soil NO3--N.

Objective: To evaluate RV longitudinal function in pulmonary hypertension (PH) patients by Two-dimensional strain (2DS). Method: 41 patients with PH were prospectively studied along with 40 control patients. RV 2DS and right heart catheterization were performed, peak systolic longitudinal strain(S) and strain rate (SRs) obtained from basal to apical RV free wall were calculated. RV Deformation indices were compared with values of conventional echocardiography and right heart catheterization with the use of linear regression. Result: (1) S, SRs of all RV free wall segments in PH group were significantly lower than those in the control group (P <0.05); S, SRs of the middle and apical segment in PH group were significantly lower than basal segment (P <0.05). (2) SRs of RV apical and middle segment in PH group correlated well with RV size and diameter. Also, S of RV apical segment correlated well with Conventional echocardiography measurement of RV size and systolic function. (3) S, SRs of the apical segment in PH group correlated well with right heart catheterization measurement of pulmonary artery pressure, pulmonary vascular resistance and stroke volume. Conclusion: The right ventricular longitudinal systolic function can be evaluated accurately and objectively by Two-dimensional strain Echocardiography.

Microbial pretreatment was applied to enhance biogas production from corn stover through solid-state anaerobic digestion, but the price of microbial strains is high. The objective of this study was to find the effects on biogas production by the naturally microbial pretreatment method. The highest cumulative biogas yield for 60-day solid-state anaerobic digestion was obtained in B group (the pretreated corn straws with cow dung), which was 19.6% higher than that of the untreated samples. The D group（the pretreated corn straws with the sludge）cumulative biogas yield for 60-day solid-state anaerobic digestion was obtained, which was 18.87% higher than that of the untreted samples. The biogas of D group increased to the range of 55%～60% methane content, while B group with the range of 75%～80%.The results indicated that the pretreated corn straws mixing cow manure can improve both the biogas production yield and the content of methane in CH4。

A three-dimensional model of collapsing bubble with jet formation and impact is presented in this paper. The strong instabilities of the jetting process, impact, and toroidal bubble rebound are dampened by a new smoothing scheme based on least squares, thus enabling a smooth transition from a singly connected bubble to a doubly connected toroidal bubble. A high order of mesh regularity is maintained by a mesh refinement procedure. The circulation of the flow around the gaseous tube of the toroidal bubble is modelled by a generalization of the vortex ring method of Q. X. Wang et al.(Comput. Fluids25, 607 (1996)). Although our results indicate some differences from previous axisymmetric results in terms of time to impact and fine features of the evolving toroidal bubble profiles, the essential physics associated with the jet impact, such as the circulation around the torus and the rebound of the toroidal bubble, are well captured in the new model. We also present, for the first time, results for fully three-dimensional bubbles in which buoyancy effects lead to oblique jetting.

Nitrogen in percolation water was observed in paddy field soil under rice/wheat rotation. Different N-application rates were designed. Porous pipes were installed in triplicate at depths of 30, 60 and 90 cm to collect the water in the period of wheat growth. Suction cups were installed in triplicate at the same depths to collect the water during the period of rice growth. NH4+, NO3-and total N in the water were analysed with a continuous-flow nitrogen analyzer. Results showed that nitrate was the predominant form of nitrogen in percolation water during the period of wheat growth. Nitrate leaching was high in early spring after the `tillering fertilisation'. More than 50 mg l-1of nitrate concentration in percolation water was observed for 30 and 60 cm in depth and more than 15 mg l-1were observed for 90 cm. The concentration decreased quickly and was very low, less than 2 mg l-1usually, in the earring stage of wheat. Nitrate in water was low, less than 1.5 mg l-1usually, when the field was flooded during the period of rice growth. Some soluble organic N existed in the water. Nitrate in percolation water increased when the field was drained. The leaching loss of nitrogen during winter wheat growth period was estimated to be about 3.4% of the N-fertiliser applied at the normal application rate of farmers; for the rice growth period it was around 1.8%. Although a reduced N-application decreased N leaching, it caused a marked decrease in crop yield.

A very simple model based on the three‐dimensional desingularized boundary integral method is applied to study the evolution of bubble(s) with or without the presence of solid structures. The choice of the desingularization parameters, which is crucial to the success of the method, is studied in the context of bubble dynamics. With the proper choice of parameters, the new model is far more efficient than previous models with virtually the same level of accuracy being achieved. This is largely attributed to the simplicity of the desingularization method. Furthermore, the new model offers a simple and attractive way for mesh refinement. Although it has limitations in the sense that, with this model the time stepping tends to slow down as two surfaces approach each other, this can be easily rectified by switching over to a direct method so that the two surfaces can be drawn closer as required in the context of jet impact. After this the new model can be reinstated to treat the complicated doubly connected geometry involving toroidal bubbles that would otherwise be very difficult to deal with. Copyright © 1999 John Wiley & Sons, Ltd.

Using anti-rhodopsin antibody, an immunofluorescence method was established in Chlamydomonas reinhardtii in order to locate rhodopsin in the cell. The method showed that rhodopsin is located in the membrane near (or around) the pigmented eyespot in green algae. In synchronized cells, the location of rhodopsin changes regularly during the cell cycle. The fluorescence (F) spot moves from the anterior region toward the posterior region of the chloroplast (cp) in the light period. Following cell division, the F spots reappear in each daughter cell whether the daughter cells are released from the mother cell wall or not. The F spot is located opposite the site of the last cleavage furrow whether the cell has divided once, twice, or three times. The F spot moves back toward the anterior region from the equatorial plane after division in the dark period. In white algae eyespot-deficient mutants, rhodopsin does not depend on the presence of the eyespot. The results further showed that rhodopsin resides in the plasmalemma.Copyright 1994, 1999 Academic Press, Inc.

The effect of roughening an initially polished aluminium surface using the Forest Products Laboratory chemical etch on the adhesive joint strength has been determined. It was found that while the lap shear strength increased rapidly with etching for short times, the fracture energy did not increase significantly until etching had occurred for at least 15 min. An atomic force microscope (AFM) was used to study the surface/interface morphology and to quantify the surface roughness. The AFM images showed that etching occurs heterogeneously across the aluminium surface and a correlation was found between the fracture energy and the fraction of etched surface. A model based on Griffith's fracture energy approach has been proposed to explain this observation. The lap shear strength was found to be more sensitive to a finer scale roughness which is generated at shorter etching times. Other observations regarding the mode of fracture and the variability in joint strength as a function of the surface roughness are explained on the basis of varying stress concentrations at the crack tip.

A DNA binding protein C3-P4 was detected in the rat ventral prostate cytosol by gel retardation assay using a 32P-labeled 31 base pair synthetic oligomers (sequence deduced from the rat prostatic steroid binding protein C3-1 gene promoter −149 to −119) as a probe. The DNA binding activity of C3-P4 DNA binding protein is sequence specific, with preference for single strand and coding strand exclusive. This protein can be detected in many androgen target tissues and controlled well by androgen in the rat ventral prostate. we speculate that this DNA binding protein may function as an accessory factor to androgen receptor (AR) for the regulation of the C3-1 gene expression.Copyright 1993, 1999 Academic Press

It had previously been hypothesized that the ability of a small number of immunity protein molecules in the cytoplasmic membrane to confer protection against the lethal effects of a channel-forming colicin involves a complex stabilized by electrostatic or polar interactions between immunity protein, the colicin channel, and specific sites on the cytoplasmic membrane surface defined by the presence of the tol gene translocation proteins. The hypothesis was tested (a) by constructing a hybrid colicin molecule, IaE1, containing the E1 channel domain, and the translocation and receptor domains of Ia, and (b) by altering charged residues in all peripheral regions of the immunity protein to neutral residues. It was concluded that the specificity of immunity protein requires neither specific translocation proteins, nor a specific arrangement of charged residues in the immunity protein. (c) In addition, by making 65 site-directed mutations, “immunity by-pass” mutants were found at five different loci, Ala474, Ser477, His440, Phe443, and Gly444, on two proposed membrane-spanning helices of the open colicin channel, one hydrophobic (A471-A488) and one amphiphilic (V441-W460). The mutants in the hydrophobic helix showed a larger bypass effect. The “bypass” phenotype could be assayed by (i) cytotoxicity and (ii) K+ efflux in imm+ cells caused by a bypass mutant but not wild-type colicin. It is concluded that the immunity protein exerts its specific effect through rapid lateral diffusion in the cytoplasmic membrane and helix-helix recognition and interaction with at least one hydrophobic and one amphiphilic trans-membrane helix of the colicin channel. Interaction with the amphiphilic helix implies that the immunity protein can react with the channel in the open state.

A new boundary element model for simulating the interaction of one or more bubbles and a free surface is described. An important feature of this model is the utilization of a nine-noded Lagrangian interpolation for the computation of surface characteristics and material velocity. Solid angles on the free surface are computed via a direct approach, as opposed to the indirect approach usually employed for closed surfaces. The evolution of the bubble is followed until the point before the reentrant jet impacts on the opposite wall of the bubble. The results of the 3D code are compared against those of a one-dimensional Rayleigh–Plesset model and an axisymmetric code. New results are presented for the interaction of two bubbles and a free surface, where fully three-dimensional features are expected.

Tb0.27DY0.73Fe2single crystal is a new kind of excellent magnetostrictive material with high λsat room temperature. We have grown large-size Tb0.27DY0.73Fe2(Terfenol) single crystals completely without contamination using a magnetic levitation cold crucible CZ (Czochralski) technique. In the growth by this method, the starting materials Tb (99.95 wt%), Dy (99.98 wt%), Fe and Mn (99.99 wt%) are used to synthesize the precursor alloy. The weight of each loading is generally 80–100 g. A pulling rate of 1–10 mm/h and a rotation of 5–20 rpm are chosen. The single crystals of Tb0.27DY0.73Fe2grown under such conditions usually have a growth direction close to [112]. In order to improve the magnetostrictive properties of the Terfenol single crystal, Mn-doped alloy (Tb0.27DY0.73Fe2−ϰMnϰ) single crystal is also prepared under similar conditions. The difference between the growth conditions is discussed also in this paper.

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The Pauwels angle has been used widely, however an accurate evaluation of this angle is difficult because of deformity of the affected lower extremity. Therefore, we designed a new measurement of the orientation of femoral neck fracture and applied this in a retrospective study to assess: 1) its reproducibility, 2) its advantages compared with the Pauwels angle, 3) its relationship with the short-term prognosis treated with three cannulated compression screws.