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921.
This study examines the species composition, diversity and economic importance of homestead forests in the household economy of central Bangladesh. The study documents 57 homestead forest species and their main usage in 90 households across three villages of Gazipur Sadar Upazila. Homestead forests in Bangladesh comprise a mixture of fruit, timber and bamboo species. While superficially homestead forestry appears unimportant in rural livelihoods, in reality the contribution is huge, both as a source of food security and for other necessary household materials. A clear understanding of the physical characteristics and economic role of homestead forests in rural livelihoods is vital for ensuring sustainable resource management. Income and production of homestead forestry on a per hectare basis are found to vary widely between landholding size classes. Significant relationships are identified between forest performance (production and income) and species richness and education level. Homestead forestry appears to be a potential subsistence income generating land-use practice in the study area. The economic scope of homestead forestry can be further enhanced provided the appropriate species composition of the forest is achieved and the education of forest owners is ensured through targeted management and policy interventions.  相似文献   
922.
This study evaluated the potential of steam pre-treatment for making highly compressed phenol-formaldehyde (PF) resin-impregnated wood at a low pressing pressure. Sawn veneers of Japanese cedar (Cryptomeria japonica) were first subjected to saturated steam at different steaming temperatures (140°-200°C), followed by impregnation with a 20% low molecular weight PF resin aqueous solution resulting in a weight gain of around 50%-55%. Four oven-dried treated veneers were laminated and compressed up to a pressing pressure of 1 MPa at a pressing temperature of 150°C and pressing speed of 5 mm/min, and the pressure was held for 30 min. Steam treatment, causing partial hydrolysis of hemicellulose, accelerated the compressibility of Japanese cedar in the PF resin-swollen condition. As a consequence, a discernible increment in density was achieved at a pressing pressure of 1 MPa due to steam pretreatment between 140° and 200°C for 10 min. It was also found that even a short steaming time such as 2 min at 160°C is sufficient for obtaining appreciable compression of PF resin-impregnated wood. The density, Young’s modulus, and bending strength of steam-treated (200°C for 10 min) PF resin-impregnated wood composite reached 1.09 g/cm3, 20 GPa, and 207MPa, respectively. In contrast, the values of untreated PF resin-impregnated wood composite were 0.87 g/cm3, 13 GPa, and 170MPa, respectively.  相似文献   
923.
Flat-sawn specimens of eight wood species, albizia (Paraserianthes falkata, 0.23 g/cm3), Japanese cedar (Cryptomeria japonica, 0.31 g/cm3), red lauan (Shorea sp., 0.36 g/cm3), European spruce (Picea abies, 0.44 g/cm3), Douglas fir (Pseudotsuga douglasii, 0.50 g/cm3), elm (Ulmus sp., 0.51 g/cm3), Japanese beech (Fagus crenata, 0.64 g/cm3), and Japanese birch (Betula maximowicziana, 0.71 g/cm3), were impregnated with low molecular weight phenol-formaldehyde (PF) resin and their compressive deformations were compared. The volume gain (VG) and weight gain due to 20% resin solution impregnation were different among species. Furthermore, the specific volume gain (VG/specific gravity), indicating the degree of swelling of the cell wall, also varied from 17.7% for European spruce to 26.4% for elm. Oven-dried specimens of each species were compressed using hot plates fixed to an Instron testing machine. The deformation behavior of resin-impregnated wood up to 10MPa was significantly different among the species. Stress development during cell wall collapse for low density wood was minimal. As a consequence, a significant increment of density occurred up to 2MPa for low density wood such as albizia and Japanese cedar. When PF resin-impregnated wood was compressed up to 2MPa and the pressure was kept constant for 30min, the density of Japanese cedar reached 1.18g/cm3, about 30% higher than the density of compressed Japanese birch, which possesses an original density that is 2.5 times higher than that of Japanese cedar. The mechanical properties of resin-impregnated wood, especially low density wood, increased with density. Hence, it is manifested that low density wood species have an advantage as raw materials for obtaining high-strength wood at low pressing pressure.  相似文献   
924.
Pharmacokinetic (PK) parameters of marbofloxacin (MRFX) in Korean cattle, Hanwoo, were determined following its intravenous (i.v.) or intramuscular (i.m.) administration at a dose of 2 mg/kg. Area under the curve (AUC0–24 hr), half-life (t1/2) and total body clearance (CLB) of i.v. MRFX were 6.87 hr∙µg/ml, 2.44 hr and 0.29 l/kg∙hr, respectively, and the corresponding values for i.m. administration of MRFX were 5.07 hr∙µg/ml, 2.44 hr and 0.39 l/kg∙hr. The suggested optimal doses of MRFX in Hanwoo cattle, calculated by integration of PK data obtained in the present study and previously reported minimum inhibitory concentration (MIC) for MRFX against susceptible (MIC ≤1 µg/ml) and intermediate (MIC ≤2 µg/ml) pathogenic bacteria, were 2.1 and 4.2 mg/kg/day by i.v. route and 3.9 and 7.8 mg/kg/day by i.m. route.  相似文献   
925.
Maropitant is a neurokinin 1 receptor (NK1R) antagonist that is clinically used as a new anti-emetic drug for dogs. Substance P (SP) and its receptor NK1R are considered to modulate gastrointestinal peristalsis. In addition, SP works as an inflammatory mediator in gastrointestinal diseases. Aim of this study is to clarify the effects of maropitant on intestinal motility and inflammation in mice. Ex vivo examination of luminal pressure-induced intestinal motility of whole intestine revealed that maropitant (0.1–10 µM) increased frequency of contraction, decreased amplitude of contraction and totally inhibited motility index in a concentration-dependent manner. We measured intestinal transit in vivo by measuring transportation of orally administered luminal content labeled with phenol red. Our results demonstrated that maropitant (10 mg/kg, SC) delayed intestinal transit. Geometric center value was significantly decreased in maropitant-treated mice. Anti-inflammatory effects of maropitant against leukocytes infiltration into the intestinal smooth muscle layer in post-operative ileus (POI) model mice were measured by immunohistochemistry. In POI model mice, a great number of CD68-positive macrophages or MPO-stained neutrophils infiltrated into the inflamed muscle region of the intestine. However, in the maropitant treated mice, the infiltration of leukocytes was not inhibited. The results indicated that maropitant has ability to induce disorder of intestinal motility in mice, but has no anti-inflammatory action in the mouse of a POI model. In conclusion, in mice, maropitant induces disorder of intestinal motility in vivo.  相似文献   
926.
The digestibility and hydration properties of wet‐ground submicron‐scale rice flour were compared with those of dry‐ground coarser microscale flours. The submicron flour (mean size 0.6 µm) was produced in a wet‐media mill with 0.3 mm zirconia beads by continuous 24 h pulverization. The solubility, water absorption index, and swelling power increased as the mean particle size decreased, reaching maximum values in the submicron flour. Starch damage was high in the submicron flour, with the absence of intact starch granules. The digestibility also increased as the particle size decreased, and it was highest in the submicron flour. These results show that wet‐ground submicron rice flour has different functional properties from dry‐ground coarser flour. The digestibility was more strongly influenced by starch damage and the water absorption index than by the mean particle size.  相似文献   
927.
It has been suggested that plasma membrane (PM) lipids play a major role in aluminum (Al) tolerance; however, no direct investigations have been carried out using PM lipids from root-tips. Here we report a new technique for PM isolation as an alternative to the laborious two-polymer phase partitioning method that is commonly applied, as follows: 1) separation of protoplasts from 1-cm root-tip portions by enzymatic digestion, 2) attachment of the purified protoplasts to glass plates coated with polylysine, 3) preparation of PM ghosts by successive burst of the attached protoplasts using three separate buffer solutions (25 mM PIPES, 5 mM EDTA, and 2 mM MgCl2, at pH 7.0) with slow stirring for 60 s. The PMs were confirmed to be devoid of organelle membranes by fluorescence microscopy, thin layer chromatography (TLC) and western blot analysis. The PM lipids obtained were found to be useful for studies on their differential permeability and lipid composition between lines of triticale or cultivars of maize under Al stress.  相似文献   
928.
N(1)- and N(3)-(4-fluorophenyl) ureas (III a-e) were cyclocondensed with ethyl chloroformate and CS(2)/KOH to yield 2-aryl-6-(4-fluorophenyl)-1,3,4-oxadiazolo[3,2-a]-s-triazine-5, 7-diones (IVa-e) and their 5-thioxo-7-ones (Va-e), respectively. The compounds III-V(a-e) have been compared with Dithane M-45 for their fungitoxic action against A. niger and F. oxyporum, and the results have been correlated with the structural features of the tested compounds.  相似文献   
929.
Variation in bread wheat including pre and post green revolutions varieties of Pakistan along with landraces was investigated for high molecular weight Glutenin subunits (HMW Gs) encoded at three genes (Glu-A1, Glu-B1, Glu-D1) with SDS-PAGE. The germplasm was diverse and unique on the basis of HMW Gs compositions and out of 14 alleles detected at all the Glu-1 loci, three belonged to Glu-A1, nine to Glu-B1 and two to Glu-D1 locus. High variation was observed in the landraces and higher gene diversity was observed between the populations as compared to the gene diversity within populations, whereas a reverse pattern of gene diversity was observed when populations were pooled across the region (higher within the regions than between the regions). A lack of relationship between the HMW Gs diversity and the altitude of collection site was observed. A data base has been generated in this study which could be expanded/exploited for cultivar development or management of gene bank.  相似文献   
930.
Bangladesh rice genetic resources collected from six distinct regions of the country were examined to obtain the diversity in glutelin acidic subunit polypeptides. Seed glutelins from 576 Bangladesh rice cultivars representing seven ecotypes were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), isoelectric focusing (IEF) electrophoresis and two-dimensional electrophoresis (2-DE: SDS-PAGE/IEF) analyses. Glutelin acidic subunit was separated into four bands, α-1, α-2, α-3 and α-4, and the variation in each of bands was detected by SDS-PAGE analysis. A higher molecular size component of α-1(α-1′) was identified in the cultivars tested. In case of α-2, α-2H with high molecular mass, α-2L with low molecular mass and α-2H/L were detected. α-3 band variation showed α-3H, α-3L, and α-3H/L, while for α-4, α-4H, α-4L bands were identified. In IEF analysis, a total of 16 bands with independent pI ranging from pI 6.30 to 7.52 were identified for the glutelin acidic subunit among the cultivars. The maximum and minimum numbers of IEF bands found were 13 and 9, respectively. The α-2L less cultivars were also lacking in pI 6.80 polypeptide in IEF. Result of 2-DE showed that pI 6.80 polypeptide was the main component of α-2L band. Transplanted Aman ecotype was the most diverse with respect to glutelin variation. Geographical distribution of glutelin variation in the Transplanted Aman ecotype differed according to the regions. The above results indicate that Bangladesh rice cultivars possess great genetic diversity in glutelin acidic subunit polypeptides. This study of indigenous rice cultivars from Bangladesh provides useful information regarding their breeding potential.  相似文献   
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