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71.
72.
Fodder trees are integral part of farming system in the hills of Nepal, but designed agroforestry interventions targeted to particular trees and crops are not widely available. This paper examines the joint productivity of an agroforestry practice in which Raikhanim (Ficus semicordata) is planted in a maize (Zea mays) and finger-millet (Eleusine coracana) cropping system at Keware Bhanjyang of the western mid-hills of Nepal. Raikhanim seedlings were planted in a row on terrace risers 2, 4 and 6 m apart in ordinary farming conditions, in a randomized block design with three replications. Maize and finger-millet were grown on the terraces as intercrops with a control plot without trees on risers in each replicate. Growth parameters of Raikhanim—height, diameter at 30 cm above ground (D30) and survival rate—were recorded annually in December until trees were lopped for fodder biomass, and crop yields were measured to determine tree-crop interaction effects. Tree height and D30 differed significantly between spacings until trees reached the lopping stage 3½ years after planting, with the highest growth in 4 m spacing. Tree lopping checked the height growth but the diameter growth continued to increase and differed among spacings after lopping. Fodder biomass increased with tree age and was highest under 4 m spacing (7.294 t/ha) followed by 6 m (5.256 t/ha) and 2 m (3.84 t/ha). Finger-millet yield in the experimental plots decreased with tree age due to shading effects, while maize yield was not substantially affected. Among spacings, control plots produced the highest finger-millet yield (1,624 kg/ha) while the 6 m spacing produced the highest maize yield (2,463 kg/ha). It is concluded that planting Raikhanim at 6 m intervals will produce additional fodder without significant effect on maize yield and only a moderate effect on finger-millet yield. The agroforestry practice of planting fodder trees on under-utilised terrace risers is a viable option for mid-hill farmers for simultaneous production of fodder and cereal crops while sustaining the hill farming system.  相似文献   
73.
Phlorotannins are polyphenolic compounds in marine alga, especially the brown algae. Among numerous phlorotannins, dieckol and phlorofucofuroeckol-A (PFF-A) are the major ones and despite a wider biological activity profile, knowledge of the G protein-coupled receptor (GPCR) targets of these phlorotannins is lacking. This study explores prime GPCR targets of the two phlorotannins. In silico proteocheminformatics modeling predicted twenty major protein targets and in vitro functional assays showed a good agonist effect at the α2C adrenergic receptor (α2CAR) and an antagonist effect at the adenosine 2A receptor (A2AR), δ-opioid receptor (δ-OPR), glucagon-like peptide-1 receptor (GLP-1R), and 5-hydroxytryptamine 1A receptor (5-TH1AR) of both phlorotannins. Besides, dieckol showed an antagonist effect at the vasopressin 1A receptor (V1AR) and PFF-A showed a promising agonist effect at the cannabinoid 1 receptor and an antagonist effect at V1AR. In silico molecular docking simulation enabled us to investigate and identify distinct binding features of these phlorotannins to the target proteins. The docking results suggested that dieckol and PFF-A bind to the crystal structures of the proteins with good affinity involving key interacting amino acid residues comparable to reference ligands. Overall, the present study suggests α2CAR, A2AR, δ-OPR, GLP-1R, 5-TH1AR, CB1R, and V1AR as prime receptor targets of dieckol and PFF-A.  相似文献   
74.
p-[18F]Fluorobenzylguanidine ([18F]PFBG) is a norepinephrine analog that has been developed as a positron emission tomography (PET) imaging radiopharmaceutical. Myocardial sympathetic innervation, neuroendocrine structures, and tumors can be noninvasively imaged with [18F]PFBG. In this study, the uptake characteristics of [18F]PFBG were investigated in 2 dogs with a spontaneous pheochromocytoma. The extent of the pheochromocytoma was well documented in both dogs on the PET study. The standardized uptake values within the pheochromocytomas were greater than 25 by 10 min, and were 37 and 50 by 45 min in each dog. A third dog that was suspected to have an adrenal mass was also studied. In this dog, the [18F]PFBG study was normal. Surgical exploration and adrenal biopsy confirmed the [15F]PFBG imaging findings in both dogs. In each dog, there was rapid blood-pool clearance (within 10 min after intravenous administration of the [18F]PFBG), with high uptake specific within the myocardium and adrenal medulla. The results indicate that [18F]PFBG may be useful for imaging canine pheochromocytomas and aid in differentiating adrenal masses.  相似文献   
75.
Despite high expectations of nongovernmental organizations (NGOs) as project partners in bilateral-aid community forestry (CF) projects in Nepal, it remains unclear whether the NGO involvement favored by donors is efficient. This study examined the influence of NGOs on local people's perceptions of CF management by using a quantitative analysis based on a questionnaire survey. Three different forest user groups (FUGs) supported by the Nepal Swiss Community Forestry Project were selected from the Dolakha and Ramecchap districts: an FUG supported by another FUG acting as an NGO, an FUG supported by an NGO specializing in CF, and an FUG without NGO support. A structured survey examined the perception of CF management based on satisfaction, involvement, and self-reliance in 244 selected households belonging to the three FUGs. Knowledge of CF and personal information was also surveyed and analyzed. The results showed that NGO involvement influences factors such as self-reliance and knowledge of CF. FUG members who were supported by an NGO or an FUG had a significantly higher perception with respect to self-reliance and knowledge than did members without such support. This indicates that experienced FUGs can serve as adequate service providers for the CF formation procedure, in a manner similar to that of NGOs. On the other hand, the limited support from NGOs or FUGs during the formation process seemed insufficient to fulfill the expectations of aid agencies with respect to the enhancement of satisfaction and active participation on the part of FUG members. If aid agencies expect NGOs and FUGs to enhance the satisfaction and participation of members, these intermediary organizations should be assigned to support more CF activities than just the formation procedure. Aid agencies should take responsibility for strengthening the capabilities of NGOs and FUGs, as needed.  相似文献   
76.
The concentration of organochlorine insecticides/metabolites, namely, lindane, heptachlor, aldrin, p,p′-DDL, p,p′-DDD, and p,p′-DDT were determined in water samples taken from two lakes, Jalmahal and Mahalon, from June 1985 to July 1986. These lakes are contaminated with moderate to high level of residues of different insecticides. In Mahalon lake the residues were highest (6.6 μg L?1) during October 1985 whereas in Jalmahal lake they were highest (9.6 μg L?1) in September 1985. In both lakes, residues of DDT exceeded the recommended limit for water quality criteria. Lindane was found in most of the samples but in lower quantities. Aldrin was the second most common residue in these lakes.  相似文献   
77.
郭仁民 《青海草业》2002,11(1):50-50
饲养牲畜是山区农业的一个组成部分。在这种半农半牧的生产体系中 ,种植、养殖及公有资源(如草地 ,森林等 )之间是一种动态关系。牲畜依赖于公有草地上的饲草及农作物和其副产品 ,但又以粪肥和耕畜的形式“回报”饲草、饲料和农作物。因此牲畜对山区农业持续发展是必须的。分析过去 1 5年间印古什地区海拔较低的农区牲畜数量的发展趋势 ,可以看出 ,在中国、印度、尼泊尔及缅甸 ,总的来说黄牛的数量在减少 ,在印度和巴基斯坦的亚热带地区圈养水牛的数量在增加。黄牛减少的原因是因为饲料来源和公用放牧地减少 ,而且圈养水牛的增加也替代了黄…  相似文献   
78.
The significance of Cryptosporidium as a causative agent of diarrhea has been assessed in bovine for a period of 2 years. A total of 940 faecal samples (470 samples in each year) both from diarrhoeic and non-diarrhoeic bovine (0-12 months age) were examined during three different seasons (rainy season, summer and winter). Overall Cryptosporidium was detected in 17.46% and 18.04% cases in first and second year, respectively. Out of 50.21% diarrhoeic and 49.79% non-diarrhoeic cases Cryptosporidium was detected in 26.79% and 8.13% in first year and 27.49% and 8.59% in second year. Year did not have any significant effect on the occurrence of cryptosporidiosis in bovine during this study period. The prevalence of cryptosporidiosis, both in diarrhoeic (61.64%) and non-diarrhoeic (47.22%) cases was highest in 0-1-month age group (P<0.01). Such a high percentage of cryptosporidiosis in clinically asymptomatic animals indicated that the particular age group of animals might be reservoir for the parasite. During this study period highest prevalence was recorded in rainy season (27.55%) followed by summer (16.99%) and winter (8.71%) (P<0.01). A total of 166 positive cases were genotyped. Molecular characterization of bovine cryptosporidiosis has been carried out by PCR-RFLP analysis of SSU rRNA gene and results indicated that Cryptosporidium parvum mainly responsible for diarrhea in bovine in India.  相似文献   
79.
The present paper demonstrates the potential of nutrient-alginate encapsulation of axenic nodal segments of pomegranate for synthetic seed technology, which could be useful in germplasm distribution and exchange. Nodal segments from in vitro shoot cultures derived from mature nodal explants (source A) or axenic cotyledonary nodes (source B) were encapsulated in calcium alginate hydrogel containing Murashige and Skoog's [Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant 15, 473–497] medium (MS) supplemented with 4.44 μM benzyladenine (BA) and 0.54 μM naphthalene acetic acid (NAA). Of various concentrations of sodium alginate (1–6%) and the complexation solution of calcium chloride (50–125 mM), a combination of 3% sodium alginate and 100 mM calcium chloride was most suitable for formation of ideal synthetic seeds. Morphogenic response of encapsulated nodal segments to seven different planting media was evaluated. Encapsulated nodal segments of both the sources exhibited shoot development only in four selected media. Of the planting media evaluated, % sprouting (shoot development) was the highest in MS medium augmented with 4.44 μM BA and 0.54 μM NAA and lowest in (1/2) MSS medium. One step germination i.e. both shoot and root formation was possible only with encapsulated nodal segments of source B in MS, (1/2) MSS and natural soil + (1/2) MSS, with MS being most effective. Encapsulated nodal segments stored up to 30 days at 4 °C were capable of sprouting. Plants regenerated from the encapsulated nodal segments were hardened off and transferred to soil.  相似文献   
80.
The GMM sheep is a carrier of Booroola fecundity (FecB) gene, which produces the twins and triplets in one lambing. The homozygous carrier GMM (FecBBB), non‐carrier GMM and Malpura (FecB++) ewes were synchronized by progesterone sponges, and the plasma progesterone concentration was measured by RIA. The results showed that the progesterone concentration did not differ significantly (p > .05) in homozygous carrier GMM (5.74 ± 1.2 ng/ml), non‐carrier GMM (5.42 ± 1.4 ng/ml) and non‐carrier Malpura ewes (5.67 ± 1.5 ng/ml). Further, quantitative expression of BMP factors/receptors and SMAD signalling genes were analysed in the ovaries of sheep by qRT‐PCR. The study showed that the expression of BMP2 was slightly higher (p > .05) in carrier GMM than that of non‐carrier GMM, but it was almost similar to Malpura ewes. Expression of BMP4 and BMP7 was significantly higher (p < .001; p < .05) in carrier GMM than that of non‐carrier GMM and Malpura ewes. Although BMP6 expression was higher (p > .05) in carrier GMM than that of non‐carrier GMM, but lower (p > .05) than the Malpura ewes. Expression of BMP15 (p < .05), GDF5 (p < .01) and GDF9 (p < .05) was significantly higher in carrier GMM than non‐carrier GMM ewes. Surprisingly, BMPR1B expression was significantly higher (p < .001) in non‐carrier GMM and Malpura than the carrier GMM ewes, while TGFβRI did not differ significantly (p > .05) among both GMM genotypes. On the other hand, expression of BMPR1A (p > .05) and BMPRII (p < .05) was higher in carrier GMM than the non‐carrier GMM, but significantly lower (p < .001) than the Malpura ewes. It was interesting to note that the expression of SMAD1 (p > .05), SMAD2 (p < .001), SMAD3 (p < .05), SMAD4 (p < .001), SMAD5 (p < .001) and SMAD8 (p < .001) was lower in the carrier GMM than that of non‐carrier GMM ewes. It is concluded that the FecB mutation alters the expression of BMPR1B and SMAD signalling genes in the ovaries of homozygous carrier GMM ewes.  相似文献   
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