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Programmed cell death 4 (Pdcd4), a tumor invasion suppressor, is frequently downregulated in colorectal cancer and other cancers. In this study, we find that loss of Pdcd4 increases the activity of mammalian target of rapamycin complex 2 (mTORC2) and thereby upregulates Snail expression. Examining the components of mTORC2 showed that Pdcd4 knockdown increased the protein but not mRNA level of stress-activated-protein kinase interacting protein 1 (Sin1), which resulted from enhanced Sin1 translation. To understand how Pdcd4 regulates Sin1 translation, the SIN15′ untranslated region (5′UTR) was fused with luciferase reporter and named as 5′Sin1-Luc. Pdcd4 knockdown/knockout significantly increased the translation of 5′Sin1-Luc but not the control luciferase without the SIN15′UTR, suggesting that Sin1 5′UTR is necessary for Pdcd4 to inhibit Sin1 translation. Ectopic expression of wild-type Pdcd4 and Pdcd4(157–469), a deletion mutant that binds to translation initiation factor 4A (eIF4A), sufficiently inhibited Sin1 translation, and thus suppressed mTORC2 kinase activity and invasion in colon tumor cells. By contrast, Pdcd4(157–469)(D253A,D418A), a mutant that does not bind to eIF4A, failed to inhibit Sin1 translation, and consequently failed to repress mTORC2 activity and invasion. In addition, directly inhibiting eIF4A with silvestrol significantly suppressed Sin1 translation and attenuated invasion. These results indicate that Pdcd4-inhibited Sin1 translation is through suppressing eIF4A, and functionally important for suppression of mTORC2 activity and invasion. Moreover, in colorectal cancer tissues, the Sin1 protein but not mRNA was significantly upregulated while Pdcd4 protein was downregulated, suggesting that loss of Pdcd4 might correlate with Sin1 protein level but not mRNA level in colorectal cancer patients. Taken together, our work reveals a novel mechanism by which Pdcd4 inhibits Sin1 translation to attenuatemTORC2 activity and thereby suppresses invasion.

This study tested the hypothesis that polyphenolic extract from Eucommia ulmoidesOliver leaf (PEE) may improve meat quality and myofiber type composition in longissimus muscle (LM). Pigs were grouped into two treatments and fed one of the following diets for 60 d: a standard diet (SD) and SD+0.08% PEE. The myofiber type composition in LM, meat quality, morphology of LM, and mRNA abundance of myosin heavy chain type (MyHC I, IIa, IIb, and IIx) were detected. The results showed that diet supplemented with PEE increased final BW (P< 0.01) and ADG (P< 0.01) and reduced F:G (P< 0.01) compared to the control group. Supplementation with PEE increased the value of pH24h(P< 0.05), redness (P< 0.05), yellowness (P< 0.05), and fiber density (P< 0.05) but decreased fiber diameter (P< 0.05). The abundance of MyHC I mRNA (P< 0.05) in the PEE group was increased, while the abundance of MyHC IIb mRNA (P< 0.05) was decreased, compared with the normal group. These results indicated that PEE supplementation improved meat quality and regulated myofiber type composition. Eucommia ulmoidesOliver polyphenols should be as a potential natural additive in the finishing pig diet to improve meat quality.

This study was conducted to determine the effect of dietary sanguinarine supplementation on serum metabolites in growing pigs. A total of 240 (Yorkshire ´ [Duroc ´ Landrace]) pigs at 6 wk of age were randomly allotted to 3 dietary treatments, with 8 replicates per treatment and 10 piglets per replicate. The dietary treatments were as follows: the basal diet (BD) control group, the sanguinarine group (BD + 0.04 g/kg), and the antibiotic group (BD + 0.2 g/kg colistin). On d 7 and 14 after initiation of the treatment, BW, ADG, ADFI, feed efficiency (F/G), and serum levels of amino acids were measured. Dietary sanguinarine and antibiotic supplementation increased ADG, ADFI, and BW compared with the control group (P< 0.05). The data showed that the serum contents of amino acids, such as Gly, Ile, Lys, Met, Arg, Ala, and Thr, increased (P< 0.05) in the sanguinarine group compared with those in the colistin group and/or control group. These findings indicate a beneficial effect of dietary sanguinarine supplementation on the serum concentrations of some essential and nonessential amino acids, which improves growth performance of growing pigs.

This study was conducted to determine the effects of different dietary protein contents on jejunal epithelial cells along the crypt-villus axis in nursing piglets. A total of 54 crossbred weaned piglets were randomly assigned to 3 dietary groups (14%, 17%, or 20% CP diets). Six piglets were randomly selected from each treatment and killed for tissue sampling at 10, 25, and 45 d after weaning. Jejunal epithelial cells were sequentially isolated along the crypt-villus axis and yielded 3 “cell fractions” (upper villus, middle villus, and crypt cells), and amino acid contents and the mRNA expression of amino acid transporters and genes related to protein degradation in jejunal epithelial cells were measured. At 10 d after weaning, dietary supplementation with 17% CP significantly increased (P< 0.05) the contents of Tau, Gly, Glu, and Cys in the upper villus compared with 14% or 20% CP. At 25 d after weaning, the 14% CP group had greater (P< 0.05) contents of Glu, Gly, Ala, Thr, Ser, Leu, and Tyr in the upper villus and Thr, Ala, Val, Ile, Tyr, and Lys in the middle villus compared with the 17% or 20% CP group. There was a similar response to feeding 14% low CP content with age, in which there was upregulation in expression, which occurred as early as 10 d postweaning for some genes (L amino acid transporter 1 [LAT1] in the middle villus and excitatory amino acid carrier 1 [EAAC1] in crypt cells) and at 25d postweaning for others (peptide transporter 1 [PEPT1] in the upper villus, B0neutral amino acid transporter [B0,+AT1] in middle villus and Y+LAT1 in crypt cells). However, the mRNA expression of cationic amino acid transporter 1 (CAT1) in the upper villus and CAT2 in the middle villus was highest (P< 0.05) in the 17% CP group compared with the 14% and 20% CP groups at 10 d after weaning. In addition, the mRNA expression of LAT2 in the middle villus was highest (P< 0.05) in the 17% CP group compared with the 14% and 20% CP groups at 25 d after weaning. The PEPT1 mRNA in the middle villus of the 17% and 20% CP groups was greater (P< 0.05) than that in the 14% CP group at 45 d after weaning. The present study showed that the different CP content levels differentially affected the amino acid content and mRNA expression of the amino acid transporter in enterocytes along the crypt-villus axis and may help identify optimal CP contents in diets for nursery piglets.

Overweight and obesity are growing global health problems. Recently, gut microbiota was found to affect energy balance by determining the efficiency of calories obtained from the diet and how that energy is utilized and stored. This study was conducted to compare the differences in colonic microbiota and their metabolites situated within the colon of two genotype pigs fed with diets formulated to meet NRC nutrient requirements. Forty-eight barrows, including 24 Bama mini-pigs (a fatty-type Chinese local pig strain) and 24 Landrace pigs (a lean-type pig strain), were fed individually from 5 wk of age to market weight. Colon tissue and its content were sampled (n= 8) at nursery, growing, and finishing phases according to their individual physiological stage. Results showed that the abundance of colon luminal bacteria, including Bifidobacterium, Lactobacillus, Clostridium coccoides–Eubacteria rectal, Faecalibacterium prausnitzii, Prevotella, Escherichia coli, and Pseudomonas aeruginosa, was greater (P< 0.05) in Bama mini-pigs compared with Landrace pigs. The colon luminal concentrations of bacteria metabolites, including short-chain fatty acids (SCFAs), polyamine, indole, and skatole, were lower (P< 0.05) in Bama mini-pigs compared with Landrace pigs. Moreover, the colon tissue of Bama mini-pigs also showed higher inflammation status and worse epithelial barrier function than that of Landrace pigs. These results suggest that the SCFA-producing bacteria may be the bacteria responsible for the obesity and the lipopolysaccharide-containing bacteria may be the bacteria responsible for the relatively terrible intestinal health status of Bama mini-pigs.

This study was conducted to determine the effect of dietary supplementation of a low dose of chito-oligosaccharide (COS) on intestinal morphology, immune response, antioxidant capacity, and barrier function in weaned piglets. A total of 120 weaned pigs (21 d of age; 7.86 ± 0.22 kg average BW) were randomly assigned (6 pens/diet; 10 pigs/pen) to 2 dietary treatments consisting of a basal diet (negative control) or the basal diet supplemented with COS (30 mg/kg) for a 14-d period. Six randomly selected piglets from each treatment were killed for blood and tissue sampling. No significant differences were observed in ADG, ADFI, and G:F between treatment and the control group. Piglets fed the COS-supplemented diet had greater (P< 0.05) stomach pH than those fed the control diet on d 14 postweaning. Dietary supplementation with COS reduced villus height (P< 0.05) and villus height:crypt depth (P< 0.05) in the ileum. Dietary COS supplementation tended to reduce villus height in the duodenum (P= 0.065) and jejunum (P= 0.058). There was no effect on crypt depth in the intestinal segments of treatment group. Piglets fed the COS-supplemented diet increased (P< 0.05) the number of intraepithelial lymphocytes in duodenum or jejunum and goblet cells of ileum. However, COS decreased (P< 0.05) the number of intraepithelial lymphocytes in ileum of weaned piglets. The concentrations of IL-10 (duodenum, jejunum, and ileum) and secretory immunoglobulin (SIgA; duodenum and ileum) were higher in piglets fed the COS-supplemented diet compared with control (P< 0.05). Dietary COS supplementation reduced (P< 0.05) the concentration of total antioxidant capacity and superoxide dismutase of the jejunum or ileum. The mRNA expression of occludin in the ileum and ZO-1 in jejunum and ileum had a significant change in piglets fed the COS-supplemented diet compared with the control group (P< 0.05). In conclusion, these results indicated that dietary COS supplementation at 30 mg/kg had no effects on promoting growth performance and tended to reduce villus height in the duodenum or jejunum of weaned piglets. The results further showed that supplemental COS at this level may cause an immune and oxidative stress response in small intestine and have compromised the intestinal barrier integrity in weaned piglets. The research will provide guidance on the low dosage of COS supplementation on weaning pigs.

Accurate prediction of phenological development in maize (Zea maysL.) is fundamental to determining crop adaptation and yield potential. A number of thermal functions are used in crop models, but their relative precision in predicting maize development has not been quantified. The objectives of this study were (i) to evaluate the precision of eight thermal functions, (ii) to assess the effects of source data on the ability to differentiate among thermal functions, and (iii) to attribute the precision of thermal functions to their response across various temperature ranges. Data sets used in this study represent >1000 distinct maize hybrids, >50 geographic locations, and multiple planting dates and years. Thermal functions and calendar days were evaluated and grouped based on their temperature response and derivation as empirical linear, empirical nonlinear, and process‐based functions. Precision in predicting phase durations from planting to anthesis or silking and from silking to physiological maturity was evaluated. Large data sets enabled increased differentiation of thermal functions, even when smaller data sets contained orthogonal, multi‐location and ‐year data. At the highest level of differentiation, precision of thermal functions was in the order calendar days < empirical linear < process based < empirical nonlinear. Precision was associated with relatively low temperature sensitivity across the 10 to 26°C range. In contrast to other thermal functions, process‐based functions were derived using supra‐optimal temperatures, and consequently, they may better represent the developmental response of maize to supra‐optimal temperatures. Supra‐optimal temperatures could be more prevalent under future climate‐change scenarios, but data sets in this study contained few data in that range.

In this study, we have attempted a growth of InSb film on the cost‐effective, (001)‐Si substrate inserting a thin intermediate‐layer of InAs quantum dots (QDs) at the InSb/Si interface. Analysis of the interface region using transmission electron microscopy reveals that, during the subsequent InSb‐growth process, InAs QDs have disappeared leaving instead a thin interlayer of InAs. The resulting 2.8‐µm‐thick InSb film on (001) Si is found to have an electron mobility of 40 907 cm2/Vs at 300 K, which turned out to be the highest value for InSb with comparable thickness grown on Si substrate.

The purpose of this work is to find optimal conditions for the growth of threedimensional 3D InAs islands on 2 × 1 001 Si substrate using modified Stranski–Krastanow S–K method. From the analysis of atomicforcemicroscopy AFM images and reflectionhighenergyelectrondiffraction RHEED patterns, we have found that InAs islands can be grown on Si when the growth temperature is in the range of 370–430 °C and also when Ininjection of more than three periods is used. At the growth temperature of 390 °C and Ininjection of four periods, uniform distribution of islands with the highest density of about 600 µm2were obtained. The average width and height of these islands were 36.1 ± 9.2 nm and 6.2 ± 2.0 nm, respectively.

Ethanolamine (Etn) is the base constituent of phosphatidylethanolamine (PE), a major phospholipid in animal cell membranes. Although Etn is toxic at relatively high levels, many types of epithelial cells require Etn for proliferation. The present study was conducted to evaluate the effects of dietary supplementation with Etn on intestine development and growth performance of weaned piglets. A total of 180 piglets were weaned at age 21 d and assigned randomly to 1 of 3 treatments, consisting of a basal diet, the basal diet with 100 ppm Etn supplementation, or the basal diet with 150 ppm Etn supplementation, for a 14-d period with 6 pens per treatment and 10 piglets per pen. On d 14, 1 piglet was randomly selected from each pen for tissue sampling. Dietary supplementation with Etn enhanced stomach weight, small intestine (SI) weight, SI length, SI weight/SI length, and SI weight/BW of weaned piglets. Moreover, dietary supplementation with Etn improved ADG and ADFI of weaned piglets. In conclusion, the results of the present experiment indicated that Etn benefited intestine development and growth performance of weaned piglets, which suggests that Etn can be explored as a feed additive to improve intestine development of weaned animals.

Abstract One of the trends on information storage device is focused on the development of micro-optical devices with optical flying head (OFH). Many different types of sliders for OFH and optical component systems have been introduced in the literature. However, the important issues on the mechanical system, which consists of suspension, swing arm and voice coil motor (VCM) part has not been discussed up to date. In this research, a swing arm type actuator with suspension for micro optical disk drive is designed and developed, basically focused on the mechanical issues, which should be solved for real application.

Abstract One of the trends on information storage device is focused on the development of micro optical disk with optical flying head (OFH). The OFH in the small form factor ODD consists of optical slider, suspension, swing arm, and so on. In order for a slider with OFH to be successfully implemented in the system, the shock performance of the head-gimbal assembly should be guaranteed for mobile applications. We design development model of suspension and swing arm for improved shock resistance using topology optimization and shape optimization. The objective of the suspension design is to decrease the equivalent mass with increasing first torsional frequency. The objective of the swing arm design is mass reduction for reducing power consumption and fast access time. In this paper, we suggest a design method for the improvement of the dynamic performance of suspension and swing arm for the OFH considering shock characteristics.

Gonadotrophin-releasing hormone (GnRH) functions as a key neuroendocrine regulator of the hypothalamic-pituitary-gonadal axis. In addition to the hypothalamus and pituitary gland, GnRH and its receptor have been detected in other reproductive tissues including the gonads, placenta and tumours arising from these tissues. Recently, a second form of GnRH (GnRH-II) and type II GnRH receptor have been found in normal ovarian surface epithelium and neoplastic counterparts. The two types of GnRH may play an important role as an autocrine/paracrine regulator of reproductive functions and ovarian tumour growth. In this review, the distribution and potential roles of GnRH-I/-II and their GnRH receptors in the ovarian cells and ovarian cancer will be discussed.

Gonadotrophin-releasing hormone (GnRH) functions as a key neuroendocrine regulator of the hypothalamic-pituitary-gonadal axis. In addition to the hypothalamus and pituitary gland, GnRH and its receptor have been detected in other reproductive tissues including the gonads, placenta and tumours arising from these tissues. Recently, a second form of GnRH (GnRH-II) and type II GnRH receptor have been found in normal ovarian surface epithelium and neoplastic counterparts. The two types of GnRH may play an important role as an autocrine/paracrine regulator of reproductive functions and ovarian tumour growth. In this review, the distribution and potential roles of GnRH-I/-II and their GnRH receptors in the ovarian cells and ovarian cancer will be discussed.

The reaction kinetics over a V2O5−WO3/TiO2 catalyst which can describe the NH3 slip from a selective catalytic reduction (SCR) reactor as well as the maximum conversion of NO over a wide range of reaction temperatures was developed to design the SCR process. The modeling of the reactor based upon the kinetics developed in the present study was successfully accomplished by the inclusion of the effect of diffusion resistance in the honeycomb reactor model. The honeycomb reactor model could directly employ the kinetic parameters obtained from the kinetic study over a packed-bed flow reactor. The model could also predict the effects of the catalytic wall thickness on the honeycomb reactor and the pore structure of the catalyst on the NO removal activity and NH3 slip, regardless of the types of the honeycomb, washcoated or extruded. The present study also identified that the diffusion resistance in the honeycomb reactor plays a critical role in the design of the commercial-scale SCR reactor despite the relatively thin catalyst layer of the reactor. Moreover, the diffusion effect was more significant for a CuHM catalyst primarily containing micropores than for a V2O5−WO3/TiO2 catalyst primarily containing mesopores. The flow pattern and the NH3 distribution in the commercial-scale honeycomb reactor are also important for a high performance of NO removal. Good distribution of the flow by the guide vanes installed in the reactor can improve the NO removal activity by more than 10% of NO conversion.

Fine-grained AA7475 aluminium alloy sheets were produced in this study by a thermomechanical treatment involving solution anneal, overageing, rolling and recrystallization steps. It has been found that the cooling rate after the intermediate overageing treatment should be fast to obtain the finest grain size. The fast cooling rate ensured the presence of relatively large particles of MgZn2 and some supersaturation prior to cold rolling. Generally, the final grain structure was heterogeneous, with bands of fine grains lying parallel to the rolling direction. In material rapidly cooled after overageing, bands of fine grains were also observed in the transverse direction and these bands were associated with shear bands formed during rolling. The fine-grained AA7475 alloy sheets with an average grain size of about 9 µm showed large tensile elongations of about 800% when deformed at 516 °C and with an initial strain rate of 5×10-4s-1.

High-temperature tensile tests have been conducted on a magnesium alloy (Mg-1.5 pct Mn-0.3 pct Ce) with randomly mixed fine and coarse grains. The microstructural examinations clearly show that different mechanisms operate in the regions of coarse and fine grains. The coarse grains deform by dislocation slip, while grain boundary sliding occurs in the fine grains. The influence of these mechanisms on each other has also been observed in terms of dislocation density, intragranular slip lines, and grain boundary sliding. The analytical equations describing the interaction of two deformation mechanisms operative in materials with regions of fine and coarse grains were derived. The analysis is applicable for determining the controlling mechanism of two interacting mechanisms. It is predicted that at a critical volume fraction of fine grains of approximately 40 pct, a transition from superplastic to nonsuperplastic behavior occurs.

Superplastic forming of AA 7475 aluminium alloy sheets of grain size ~15 µm has been studied by imposing hydrostatic back pressures of between 0·1 and 2·86 MPa. Qualitative and quantitative studies of the effect of hydrostatic pressure on the cavitation of the alloy were carried out on formed domes. On the diametral section of a dome, cavities were mainly found in the centre of sheet thickness, where the grains were coarser than those near the surface. Dome height at failure was significantly increased by imposing hydrostatic back pressures during superplastic forming. For domes that were formed into top hat shapes, a maximum height/base radius ratio of 2:1 was obtained under a hydrostatic pressure of 2·86 MPa. Flat tensile testpieces were machined from top hats to evaluate the room temperature mechanical properties. It was found that the postformed ductility deteriorated with superplastic strain more rapidly than did the ultimate tensile strength. The effect of surface grooves, which were observed in formed domes and top hats, on postformed properties was also examined.MST/1576

The effect of the preferred orientation of SiC whiskers (SiCw) in an alumina based ceramic cutting tool material on its fracture behaviour has been studied. During hot pressing, the SiC whiskers tend to be oriented in planes perpendicular to the hot pressing direction (?HPD). The fracture toughness measured on the ?HPD plane was found to be noticeably higher than that measured on the plane parallel to the HPD (? HPD). Cutting tests revealed that the fracture resistance of the tool was dependent on which surface (? or ? HPD) was used as the rake face. Fracture behaviour and cutting results are discussed with respect to the stress distributions predicted using a finite element method. It is suggested that, with regard to fracture resistance, the selection of the ? HPD plane as the rake face is more favourable.MST/1565