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11.
As titanium oxide is a well-known photocatalyst, we investigated the effects of silver content and nanostructural morphology on the photocatalytic degradation of two dyes, methylene blue and rhodamine B. Two nano-formulations were utilized, including nanofibers and nanoparticles. Silver-grafted titanium oxide nanofibers were synthesized using the electrospinning of silver nitrate/titanium isopropoxide/poly(vinyl acetate) sol-gel. The nanoparticulate form was obtained by calcination of a ground powder prepared from the same electrospun sol-gel. The results affirmed the advantage of the silver-grafted titanium oxide nanostructures over the silver-free ones. Increasing the silver content in the nanofibers led to increases in their surface area, which is an important parameter in heterogeneous catalytic chemical reactions. Therefore, the results strongly suggest the use of silver-grafted titanium oxide in a nanofibrous form. These results further support utilizing Agloaded titanium oxide nanofibers as a photocatalyst.  相似文献   
12.
Random amplified polymorphism DNA (RAPD) and bulk segregant analysis (BSA) approaches were used to characterize the molecular marker linked to the Phytophthora infestans resistance gene Ph-3 in tomato. A total of 800 RAPD primers were screened. One RAPD marker UBC#602 was identified to be tightly linked to the Ph-3 gene. The marker was successfully converted into a co-dominant sequence characterized amplified region (SCAR) marker. The SCAR marker SCU602 was used to analyze 96 F2 progenies and fitted the expected 1:2:1 Mendelian segregation ratio. Forty one tomato inbred lines were screened using the SCAR marker in comparison with a reference marker linked to the Ph-3 gene and both markers gave the same results. SCU602 was further validated for association to resistance and its potential in MAS in 72 tomato lines and cultivars. The marker identified three genotypes harbouring the resistance allele. This SCAR marker can be used in breeding programs for the selection of the Ph-3 gene for Phytophthora infestans resistance.  相似文献   
13.
Besides its primary role in the digestion and absorption of nutrients, the intestine also interacts with a complex external milieu, and is the first defense line against noxious pathogens and antigens. Dysfunction of the intestinal barrier is associated with enhanced intestinal permeability and development of various gastrointestinal diseases. The branched‐chain amino acids (BCAAs) are important nutrients, which are the essential substrates for protein biosynthesis. Recently, emerging evidence showed that BCAAs are involved in maintaining intestinal barrier function. It has been reported that dietary supplementation with BCAAs promotes intestinal development, enhances enterocyte proliferation, increases intestinal absorption of amino acids (AA) and glucose, and improves the immune defenses of piglets. The underlying mechanism of these effects is mediated by regulating expression of genes and proteins associate with various signaling pathways. In addition, BCAAs promote the production of beneficial bacteria in the intestine of mice. Compelling evidence supports the notion that BCAAs play important roles in both nutrition and intestinal health. Therefore, as functional amino acids with various physiological effects, BCAAs hold key roles in promoting intestinal development and health in animals and humans.  相似文献   
14.
This study aimed to divide the mandible into skeletal units based on three‐dimensional (3D) muscular anatomy with microcomputed tomography (micro‐CT) of Sprague–Dawley rat. Five normal rats were micro‐CT scanned at 12 weeks of age before and after contrast enhancements for the masticatory muscles. Three‐dimensional reconstruction of the mandible was performed from the initial micro‐CT images, followed by segmentation of the masticatory muscles using the second enhanced micro‐CT data. Bone and muscle models were superimposed based on the teeth and bony structures to evaluate muscular orientation and attachment. The mandible was divided into skeletal units using the bony structures and muscle attachments. The mandibular foramen and mental foramen were adopted as the reference points based on their anatomical and developmental significance. The skeletal units consisted of the condylar, coronoid, angular, body and symphyseal units. Further evaluation of these units in relation to development, growth, and other biology and medicine will be helpful in elucidating their biological identities.  相似文献   
15.
Three-year-old jack pine (Pinus banksiana Lamb.) seedlings in pots were sprayed with gibberellin A4/7 solution during the 1989 growing season. Unsprayed and sprayed controls, and seedlings sprayed with gibberellin A4/7 at three concentrations (200, 400 and 600 mgL-1) were tested in each of five different treatment periods based on jack pine morphogenesis. Each spraying period consisted of five weekly applications between May and October. Trees produced significantly more pollen cones than the two controls when sprayed at 400 or 600 mgL-1 during July and early August. Spraying at 600 mgL-1 during May–June and June–July produced significantly more seed cones than the two controls, as did spraying at 400 or 600 mgL-1 during July and early August. The best treatment for both pollen- and seed-cone production was weekly spraying at 400 or 600 mgL-1 gibberellin A4/7 from early July, which coincided with the end of terminal shoot elongation, through early August, which coincided with microsporophyll initiation in the pollen-cone buds and initiation of the potential seed-cone buds.  相似文献   
16.
To evaluate the differences in graft survival and histopathological characteristics between full-thickness and lamellar orthotopic corneal xenotransplantation in a pig-to-rabbit model, we orthotopically transplanted a full-thickness or the anterior half of a pig's cornea onto the OD of 16 rabbits. As a result, the median survival were 16.83 and 29.07 days for the full-thickness and lamellar xenografts, respectively ( P  = 0.0005). Histologically, the full-thickness corneal xenografts had massive infiltration by eosinophils, whereas the lamellar xenografts showed predominantly mononuclear infiltrates ( P  < 0.05). Given these preliminary findings, lamellar corneal xenografts in rabbits survived longer than the full-thickness xenografts and each type of graft demonstrated different rejection mechanisms.  相似文献   
17.
Two nitrogen balance studies were conducted to evaluate the relative bioavailability values (RBV) of dl-methionine (dl-Met) and dl-methionine hydroxy analog calcium salt (MHA-Ca) to l-methionine (l-Met) as Met sources fed to pigs. In experiment 1, 42 pigs were assigned to 7 treatments feeding with basal diet (BD) formulated to be deficient in Met (0.22% standardized ileal digestible basis) but adequate in other amino acids. Diets included (1) BD, (2) BD + 0.025% dl-Met, (3) BD + 0.050% dl-Met, (4) BD + 0.075% dl-Met, (5) BD + 0.025% l-Met, (6) BD + 0.050% l-Met, and (7) BD + 0.075% l-Met. Increasing levels of l-Met and dl-Met enhanced N retained (g/d) and N retention (% of intake) linearly (P < 0.01). Using a linear slope ratio procedure, a product-to-product RBV of dl-Met compared with l-Met was 94% (95% confidence limits: 65% to 123%) based on N retained expressed as g/d and 99% (95% confidence limits: 70% to 128%) for N retention expressed as % of intake. In experiment 2, 42 pigs were allotted to 7 treatments in another N-balance trial. Diets included (1) BD, (2) BD + 0.025% l-Met, (3) BD + 0.050% l-Met, (4) BD + 0.075% l-Met, (5) BD + 0.030% MHA-Ca, (6) BD + 0.060% MHA-Ca, and (7) BD + 0.089% MHA-Ca. An increase in dietary inclusion rates of l-Met increased (P < 0.01) N retained (g/d) linearly while increasing levels of MHA-Ca had no effects (P > 0.05) on N retained (g/d) and N retention (% of intake). Using linear slope-ratio regression, the RBV of MHA-Ca compared with l-Met was 70% (95% confidence limits: 59% to 81%) on a product-to-product basis or 83% on equimolar basis based on N retained expressed as g/d. Overall, the mean RBV of dl-Met to l-Met of 97% (95% confidence limits cover 100%) indicated that dl-Met and l-Met are equally bioavailable as Met sources in pigs. Compared with l-Met, the RBV of MHA-Ca was lower at 70% (95% confidence limits: 59% to 81%) on a product-to-product basis or 83% on equimolar basis in starter pigs.  相似文献   
18.
19.
Rice seed was treated by high proton beam irradiation up to 1,200 Gy in order to elucidate physicochemical properties of irradiated rice starch. The decrease of amylose content in two rice cultivars ranged 3.5 to 3.6% compared to the non-irradiated rice under the highest proton beam irradiation (1,200 Gy). Gel consistency in japonica rice cultivar Ilpum was significantly increased with increasing proton beam irradiation. Its values approached 9.7 in the Ilpum rice cultivar and 8.7 cm in the Hanmaum rice cultivar. The peak viscosity, hot peak viscosity, cool peak viscosity, and setback were significantly decreased with increasing proton beam dose. High proton beam irradiation caused a significant decrease in the onset temperature (T o ), peak temperature (T p ), conclusion temperature (T c ), and enthalpy change (ΔH). Gelatinization range (R) in two rice cultivars was more broaden in higher proton beam irradiation than in low proton beam irradiation. The crystallinity degree of two rice starches irradiated with high proton beam was significantly increased and it ranged from 3.25 and 4.39% compared to the non-irradiated rice starches. It might be deduced that proton beam irradiation causes changes of starch, especially at high irradiation of proton beam.  相似文献   
20.
Seventy‐two pigs at 34.4 kg body weight (BW) were allotted to two treatments with six replicates/treatment and six pigs/pen: the CON (negative control, no added selenium (Se)) and the OS (0.36 mg/kg added selenium from selenium‐enriched yeast). Pigs were fed until 130 kg BW. The CON diet contained 0.18 mg/kg indigenous Se whereas the OS diet contained 0.54 mg/kg Se. Blood samples were collected at 130 kg BW and further processed for microarray analysis, prepared with 885 genes related to immune function of pigs. Among those, 28 genes related to improved immune status and innate immunity were up‐regulated (P < 0.05) in leukocytes from Se‐fed pigs and those include major histocompatibility class I (> 1.66), arginase I (> 1.27), integrin beta‐1‐subunit (> 1.20), toll like receptor 2 (> 1.12) and double‐stranded RNA‐dependent protein kinase. However, 24 genes including tissue factor (< 4.70), serum amyloid A‐2 protein (< 3.11) and p27Kip1 (< 1.42) were down‐regulated (P < 0.05) in leukocytes from Se‐fed pigs. Expression of four selected genes was validated using quantitative PCR (qPCR) showing significant correlation between mircroarray analysis and qPCR analysis. This study indicates that a long‐ term dietary supplementation (0.3%) of organic Se improves the expression of genes that are related to enhanced immunity of pigs.  相似文献   
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