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A newly-developed in situ neutron diffraction method has been employed to search elastic tension induced lattice distortions in DD10 single crystal nickel-based superalloy under tensile condition of 500 °C/760 MPa. Multiple lattice reflections, viz., {002}, {003}, {220}, {311} were in situ measured. Two samples which were stretched along [001] direction and 18° deviation of [001] direction, respectively, were measured for comparison. As samples were heated to 500 °C, the lattice stress of both samples gradually relaxes. With 760 MPa tension applied, the response of reflections of γ and γ’ phases were anisotropic. Compared with 0° sample, 18° sample resulted in distinguishable results. Due to the large extra stress, the mismatch along [001] direction is much negative, whereas that perpendicular to [001] get slightly positive. Owing to the different stress states, γ phase is divided into two conditions. The tetragonal distortion with c/a of γ⊥ channel is largest, while that of γ’ phase is small. The distortions at γ/γ’ phase boundary result in broadening the boundary of γ’ phase. In this work, a new elastic-induced lattice distortion model that enhances apprehensions to the constraint effect between γ and γ’ phases is built, which might provide the directly experimental evidence to the origin of rafting.

This study investigated the effects of dietary Arginine (Arg) on performance, intestinal antioxidative capacity, immunity, and gut microbiota in Chinese yellow-feathered chickens. One thousand two hundred 1-day-old female Qingyuan partridge chickens were randomly assigned to 5 groups with 6 replicates of 40 birds each. Chickens were fed diets with 5 levels of total Arg (8.5, 9.7, 10.9, 12.1, and 13.3 g/kg) without antibiotics for 30 d. The ADFI, ADG, and feed conversion ratio were improved with dietary Arg levels (P < 0.05). The proportions of CD3+ and CD4+/CD8+ lymphocytes responded in a linear (P < 0.05) manner and those of CD4+ in a linear or quadratic (P < 0.05) manner as dietary Arg levels increased. Dietary Arg level had a linear (P < 0.05) or quadratic (P < 0.05) effect on the gene expression of glutathione peroxidase 1, heme oxygenase 1, nuclear factor erythroid 2-related factor 2, and the activities of glutathione peroxidase and total antioxidative capacity in the jejunum and ileum. The relative expression of IL-1β, myeloid differentiation primary response 88, and Toll-like receptor 4 decreased linearly (P < 0.05) in the ileum with increasing dietary Arg levels; secretory IgA contents were increased. In addition, sequencing data of 16S rRNA indicated that dietary Arg increased the relative abundance of Firmicutes phylum, Romboutsia and Candidatus Arthromitus genera, while decreased that of Clostridium sensu stricto 1. A diet containing 12.1 g Arg/kg promoted growth performance, intestinal antioxidation, and innate immunity and modulated gut microbiota in yellow-feathered chickens.

By utilizing a versatile solution combustion synthesis (SCS) method, pure and well-crystallized Sr2MgSiO5:Eu2+, Mn2+ phosphors for white LED were successfully prepared. The results show that the obtained Sr2MgSiO5:Eu2+, Mn2+ phosphors have good crystallinity, and strong emission under near-ultraviolet (NUV) light excitation, which emits tri-band colors (blue, green, and red, RGB) peaking at 462, 535, and 668 nm, respectively. The emission spectrum with the peak at 462, 535 nm corresponds to the transition from the 4f65d excited state to the 4f7 ground state of Eu2+ ion, and the red emission band of 668 nm is attributed to 4T → 6A transition of 3d5 level of Mn2+ ions. It is suggested that the as-prepared nanostructure Sr2MgSiO5:Eu2+, Mn2+ samples as a single-host full-color phosphor have high potential for phosphor-converted white LEDs application.

Multi-walled carbon nanotubes (MWCNTs) coated with metal titanium or carbide layers were prepared by heating a mixture of TiCl3, TiH2, and MWCNTs under vacuum. The resulting MWCNT–Ti(TiC) materials had a uniform and conformal core–shell structure. The thickness of the Ti(TiC) layer was determined by the deposition temperature and time. The amount of TiC in the shell depended primarily on the deposition temperature. Whether a metal or carbide coating was obtained was determined by controlling the deposition temperature. Ti(TiC)-coated MWCNTs showed better field emission properties than did pristine MWCNTs. This deposition method should prove to be a versatile route for fabricating other one-dimensional core–shell materials.

A series of boron carbide (B 4 C) matrix composites with different contents of Al, were synthesized by reaction hot-press sintering with milled B 4 C and pure metallic Al powder at 1600 °C for 1 h. X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscopy (TEM) were used to identify the phase constituent of the milled powders and the composites. The results have shown that parts of B 4 C and Al particles were oxidized to boron oxide (B 2 O 3 ) and alumina (Al 2 O 3 ) during the milling. Thermit reaction occurred and B 2 O 3 was reverted during hot-press sintering. A ternary phase of Al boron carbide (Al 8 B 4 C 7 ) was found in the composites, and the B 4 C transformed to a rich boron phase (B 6.5 C) because of the superfluous boron in the system.

Carbon-coated YC2 nanocapsules were prepared by arc-discharging bulk yttrium in methane. The core/ shell structure was obtained, where a polyhedral crystalline YC2 core was coated by defective graphite shell with size of 1–3 nm. The hydrolyzing of the zero-dimensional superconductors YC2 was controlled by the shell. The magnetic properties of the carbon-coated YC2 nanocapsules show that the dimensional effect has a very small influence on its superconducting transition temperature. The Raman spectrum of the carbon-coated YC2 nanocapsules shows that the shell is defective graphite and also suggests that the aberrance structure of the carbon shell is related to the zone-edge vibration of the YC2 core.

Ultrasonic vibration electrical discharge machining (UEDM) in gas is proposed in this paper. It is shown that electrical discharge machining with ultrasonic aid can be achieved well in gas medium. The tool electrode is formed to be thin-walled pipe, and high pressure gas medium is supplied through it. During machining, ultrasonic vibration of workpiece can improve the machining process. The molten workpiece material can be ejected out from base body of workpiece with the aid of ultrasonic vibration and be removed/flushed out of the working gap without being reattached to the electrode. A theoretical model to estimate the material removal rate has been developed. Selecting 45# steel and copper as the workpiece material and electrode material, respectively, experiments have been carried out, the results showing that UEDM is a method with a high material removal rate (MRR). The greatest advantages of this technique are lower pollution and low electrode wear ratio.

A new method of ultrasonic vibration electrical discharge machining (UEDM) in gas is proposed in this paper. It is shown that electrical discharge machining (EDM) with ultrasonic aid can be achieved well in a gas medium. The tool electrode is formed into a thin-walled pipe, and a high pressure gas medium is supplied through it. During machining, ultrasonic vibration of the workpiece can improve the machining process. Molten workpiece material can be ejected from the base body of the workpiece with the aid of ultrasonic vibration and be removed/flushed out of the working gap without becoming reattached to the electrode. Selecting #45 steel and copper as the workpiece material and electrode material, respectively, experiments have been carried out, the results showing that UEDM is a method with a high material removal rate (MRR). The greatest advantages of this technique are lower pollution and a low electrode wear ratio.

Two growth trails were conducted to determine the optimum ratio of histidine in 10-20 kg piglet ideal protein model. Four diets containing 0.23%, 0.31%, 0.39% and 0.47% digestible histidine (0, 0.08%, 0.16%, 0.24% crystalline histidine supplemented into the basal diet) were fed to 96 piglets of mean initial body weight 10.3 +/- 1.08 kg for 18 d in Experiment 1. Average daily gain, average daily feed intake and feed conversion efficiency were inhibited (P < 0.05) with the diet containing 0.23% digestible histidine. Performance was maximized with 0.31% digestible histidine. As the dietary histidine increased, blood urea nitrogen and serum cholesterol concentration were influenced significantly. The concentrations of serum histamine and free histidine did not change with increase in digestible histidine from 0.23 to 0.31%, but higher supplementation resulted in a significant linear increase in both serum parameters. It was concluded that the dietary level of 0.23% digestible histidine does not meet the requirement of 10-20 kg piglets. Based on the results from Experiment 1, Experiment 2 was designed to determine the optimum ratio of lysine:histidine in the ideal protein model of 10-20 kg piglet. Ninety-six Large White x Landrace piglets weighing 10.2 +/- 0.88 kg were divided into 4 groups. They were fed four diets containing 0.26, 0.29, 0.32 or 0.35% digestible histidine, formulated by adding 0.03, 0.06, 0.09 or 0.12% crystalline histidine to the basal diet. The trial lasted for 21 days. Results showed that performance was significantly improved with 0.32 and 0.35% digestible histidine. As dietary histidine increased, blood urea nitrogen tended to decrease but not significant at P < 0.05. Serum cholesterol concentration increased with an increase in dietary histidine level and reached a maximum at 0.35%. Serum histamine increased with increasing dietary histidine. Free serum histidine increased linearly with increased dietary histidine. From both experiments it was concluded that the digestible histidine requirement for 10-20 kg piglets was 0.31% and that the optimum ratio of dietary lysine to histidine should be 100:30. The concentrations of cholesterol, histamine and free histidine in serum were sensitive parameters to measure changes in dietary histidine levels.

Suspension-feeding behaviour in the scallop Chlamys farreri of 72±1 mm shell length was studied in response to wide variations in the amount and composition of suspended seston. Clearance rates (CR; l h−1) with which scallops removed all particles larger than 3.9 μm equivalent spherical diameter varied over an order of magnitude, initially increasing to maxima in separate unimodal relations with different measures of dietary abundance that included total particulate volume (VOL; mm3 l−1), total particulate mass (TPM; mg l−1), particulate organic mass (POM; mg l−1), particulate organic carbon (POC; mg l−1) and chlorophyll a (CHL; μg l−1), before declining with further increases in seston concentration. Most variance in CR was associated with VOL (47%), compared with TPM (29%), POM (32%), POC (29%), PON (27%) and CHL (20%). This suggests morphological limits to feeding behaviour, as adjustments in CR were primarily dependent upon total seston volume, rather than any gravimetric measure of abundance. Nevertheless, stepwise regression indicated that VOL and CHL together accounted for as much as 58% of the variance in CR; more than for VOL alone (p

The mechanism of K + ions implanted in both pristine polyacetylene and FeCl 3 -doped polyacetylene has been studied using an electron spin resonance (ESR) spectrometer and a four-probe technique. The temperature dependence of ESR characteristics (spin susceptibility, peak-to-peak linewidth) for the samples has been analysed within the soliton model. The ESR results are consistent with our previous studies.

The image analysis method is used to determine the hydrogen content in specimens of Zircaloy-4. Two parameters, surface density of hydride, Sv, and degree of orientation, Ω, are defined to represent separately the hydrogen content and the orientation of hydrides. By analysing the stress-relieved Zircaloy-4 specimens with known hydrogen content from 100 to 1000 ppm, a relationship is established between the parameter Sv and the hydrogen content when the magnifications of the optical microscope are 1000 and 250. The degree of orientation for the hydride in the stress-relieved Zircaloy-4 cladding is about 0.3.

Successful vapour phase epitaxial (VPE) growth of ZnSxSe1-x on (100) GaAs substrate is reported. The solid composition x can be controlled by varying the substrate temperature. This result is discussed in terms of adsorption and desorption processes at the vapour-solid interface. An activation energy of E=24.3 kcal/mol is decuced for the S/Se mixture in the solid. The effect of lattice relaxation is investigated. The perpendicular relative mismatch (Δa⊥/a) is measured and a maximum value of -6x10-3 is found for x > 0.2. The emission from exciton-exciton interaction was observed in ZnSxSe1-x(x=0.1, 0.2) epilayers at 77 K for t he first time. It indicates that high quality ZnSxSe1-x epilayers have been grown by VPE method.

Introduction Bile acid diarrhoea (BAD) results from excess luminal bile acids (BA) in the colon. Most BAs are reabsorbed at the terminal ileum. Increased colonic BA occur secondary to ileal disease or resection (common in Crohn’s disease [CD]) leading to BA malabsorption and secondary BAD (SBAD). Primary BAD (PBAD) occurs in the absence of overt ileal disease or malabsorption. The peptide FGF19 is produced from enterocytes in response to BA absorption and maintains homeostasis of the BA pool size by inhibiting hepatic BA synthesis. Impaired ileal FGF19 production may underlie the excess faecal BA observed in PBAD and may be contributory in CD as a result of increased hepatic BA synthesis. We aimed to investigate whether BA-induced expression of FGF19 in the ileum is reduced in patients with PBAD or CD. Method Patients attending for colonoscopy (n = 58) were prospectively recruited and gave informed consent to give additional ileal biopsies. 14 patients had CD (4 with previous right hemi colectomy and 10 without), 16 patients had unexplained diarrhoea and had SeHCAT tests, and 28 controls. Groups of 2–3 biopsies (explants) were incubated separately for 6 h with either BA-free culture media (unstimulated controls), chenodeoxycholate (CDCA) or glyco-CDCA (GCDCA), both at 50 µM. After RNA extraction and cDNA synthesis, FGF19 expression was quantified relative to GAPDH by RT-PCR. Results In patients with unexplained diarrhoea SeHCAT 7d retention values were 15% in 9 who were normal diarrhoea controls. A positive correlation was found between SeHCAT retention and the magnitude of the fold change in FGF19 expression stimulated by either CDCA (r = 0.50, n = 16, p = 0.02) or by GCDCA (r = 0.76, n = 7, p = 0.02). The median CDCA stimulated fold change in FGF19 expression was significantly lower in CD compared to controls (87, n = 12 vs 251, n = 28, p = 0.03) and a similar non-significant trend was observed for median GCDCA stimulated expression (97, n = 10 vs 156, n = 13, p = 0.18). Conclusion Ileal explants from patients with lower SeHCAT 7d retention had a lower response to both CDCA and GCDCA. Patients with CD had lower responses to CDCA. As uptake of GCDCA is dependent on carrier-mediated apical BA uptake but CDCA is not, this implies abnormalities in the intracellular ileal FGF19 response to BA. A reduced capacity to induce ileal FGF19 expression in response to absorbed BA is proposed to increase faecal BA due to increased hepatic BA synthesis in primary BAD. In secondary BAD an impaired ileal BA FGF19 response may lead to an increase in BA synthesis and faecal BA that is disproportionate to the degree of ileal BA malabsorption. Disclosure of interest None Declared.

This paper systematically discusses the influence of bonding pressure, bonding temperature and humidity on the adhesion strength of bumpless die (aluminum surface) with two kinds of Anisotropically Conductive Films (ACFs). Evaluated by die shear test, the adhesion. strength between the ACFs and aluminum is not affected seriously by bonding pressure but it increases when bonding temperature increases. Adhesion strength at the ACF/aluminum interface increases while the adhesion at the ACF/glass surface decreases after aging in the same high temperature and high humidity environment. For the ACF/aluminum layer, the adhesion enhancement mechanism after humidity aging is studied by SAM, SEM & EDX, and XPS. Moisture mainly diffused into aluminum and resulted in an oxidation reaction, instead of diffusing into adhesive to make it swell. Less swelling of adhesive and less delamination occurred at the ACF/aluminum surface. Thus, the adhesion strength of shear samples increased after temperature/humidity exposure. In addition, the oxidation reaction can provide a fresh rougher surface that may enhance adhesion strength.

A novel method for the determination of the Young's modulus and residual stress of micromembranes is described. Since thin film structures are frequently used in micro devices, characterization of mechanical properties of thin films is desired by the design and fabrication of micro devices. This paper characterizes the mechanical properties of thin micromembranes under compressive stresses with or without initial deflections, which are fabricated by silicon micromachining techniques. The relation between the deflection and the pressure applied to a square membrane is induced by modeling the membrane as a square plate having large deflection with clamped boundaries and the presence of internal compressive stress. The Young modulus and residual stress are simultaneously determined by using the load deflection behavior of a square membrane. The deflection of the membrane is measured using a micro interferometer. The mechanical properties of silicon nitride and silicon oxide membranes and polycrystalline silicon compound membranes with silicon nitride film are measured. This method use simple apparatus, and the fabrication of samples is very easy.

Voltage-gated Na+ channels are regulated in response to oxygen deprivation in the mammalian cortex. Past investigations have demonstrated that Na+ channel protein expression is up-regulated in the immature brain exposed to prolonged hypoxia. Since it is unknown as to which Na+ channel subtype(s) is involved in this regulation, we used RT-PCR to assess the effect of hypoxia on Na+ channel I, II and III alpha-subunit mRNA expression in the developing rat cortex. Na+ channel II mRNA tended to increase during early development, whereas Na+ channel I and III did not change or slightly decreased with age. Hypoxic exposure for 1-day had no effect on Na+ channel expression, while 5-day hypoxia significantly increased Na+ channel III density, with a slight increase in Na+ channel I and no appreciable change in Na+ channel II. These results suggest that Na+ channel subtype expression in the developing cortex is differentially regulated in response to prolonged hypoxic exposure.

Introduction The expression of the enteric hormone FGF15 is largely restricted to the ileum in the mouse. FGF15 has also been shown to be the most BA responsive gene in mouse ileum. FGF19 is the human orthologue of FGF15 and is thought to have roles in the regulation of bile acid pool sizes and BA homeostasis. We set out to investigate the distribution of FGF19 expression in the human GI tract and FGF19 gene responses to BA in human ileum. Methods Biopsies of normal ileal mucosa were obtained from 29 patients undergoing colonoscopy. Basal ileal FGF19 expression was compared to colonic (n=9) and duodenal FGF19 expression (n=3). Ileal biopsies (explants) from 20 patients were incubated for 6h in short term tissue culture in parallel with BA (chenodeoxycholic acid [CDCA] or glyco-chenodeoxycholic acid [GCDCA]) or without (control explants). 3 Duodenal and colonic explants from were also studied. Real-time qRT-PCR was used to measure expression of transcripts for FGF19, and several other ileal BA regulatory genes (ASBT, IBABP, SHP, FXR, OSTα and OSTβ). FGF19 protein levels in culture fluid were also measured by specific ELISA. Results Transcripts for FGF19 were detected in human ileum, but not colon or duodenum. FGF19 expression was greatly induced in all ileal explants incubated with BA: geometric mean induction of 316-fold by 50 μM CDCA (n=17, p=0.0003), and 231-fold by 50 μM GCDCA (n=11, p=0.001). Measured by ELISA, the amount of FGF19 protein released into the culture media was significantly higher from the explants incubated with 50 μM of BA (CDCA 51 pg/explant, range 8–169, n=11 and GCDCA 38 pg/explant, range 3–113, n=10) compared to the matched control explants (8pg/explant, range 0–46 [p=0.0008] and 6 pg/explant, range 0–13 [p=0.0022] respectively). The EC50 for CDCA was 20 μM and 24 μM for GCDCA. Responses to both BA were similar at 50 μM and 100 μM. 6 h incubation of duodenal and colonic explants with 100 μM CDCA or GCDCA showed that FGF19 expression levels were Conclusion FGF19 is expressed in human ileum but not the colon or duodenum. Ileal FGF19 expression is highly responsive to CDCA and GCDCA, compared to other BA regulatory genes. No significant induction of FGF19 expression is observed in duodenum or colon with BA. Ileal BA induced FGF19 responses could be studied in clinical conditions of dysregulated BA homeostasis. Competing interests None declared.

Powder X-ray diffraction, variable temperature magnetic susceptibility, and zero-field Mossbauer spectroscopy measurements were used to characterize the new phase Li2Fe2(MoO4)3. This material is obtained simply by the mixing of solutions of lithium iodide in acetonitrile with solid Fe2(MoO4)3 at ambient temperature. The reaction is entirely reversible using bromine as an oxidant. Li2Fe2(MoO4)3 possesses the high-temperature orthorhombic ferric molybdate structure and Guinier photographs were completely indexed in space group Pnca with cell constants a = 9.3483(5), b = 12.8974(9), and c = 9.4941(6) A versus the monoclinic ( P2 1 a ) Fe2(MoO4)3 precursor phase. Chemical analytical data, room-temperature magnetic susceptibility and Mossbauer spectroscopy indicate essentially complete stoichiometric reduction of the latter compound. Magnetic hyperfine splitting of the zero field Mossbauer spectrum below 12.5 K indicates a three-dimensional magnetically ordered state which susceptibility results show to be weakly ferromagnetic owing to probable canting of antiferromagnetically coupled lattices. Above ∼40 K, the material obeys a Curie-Weiss law whose parameters are C = 3.51 emu/mole, μeff = 5.30β and ϑ = −19 K.