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71.
This study investigated the effect of credit constraints and credit unconstraints on the technical efficiency of hybrid maize growers in the Khyber Pakhtunkhwa Province(KPK) of Pakistan. The primary data were collected by a direct elicitation method from 510 maize growers of KPK Province. Stochastic frontier model techniques were used for technical efficiency analyses. The results revealed that the mean technical efficiency difference between the two groups was 10.2%. The results of technical inefficiency effect modeling demonstrated that education of the household head, family size, number of married family members, off-farm income, farming experience, tractor drill, water irrigation through a lined course, certified seed, extension services, household saving variables, and a credit size variable had positive effects on technical efficiency for both credit constrained farmers(CCFs) and credit unconstrained farmers(UCCFs). In addition, age of household head and fragmented land values had negative effects on technical efficiency for both groups. However, the interest rate had positive and negative impacts on the technical efficiency of CCFs and UCCFs, respectively. Our results have significant implications for policies related to land use, interest rate, and banking sector expansion in the rural areas of Pakistan.  相似文献   
72.

The study aimed to investigate if vegetable-based high-energy mash diets supplemented with NaHCO3, l-arginine?+?vitamin C, and vegetable oils were effective against tachycardia and polycythemia in the broiler chicken. A total of 256 Ross-308 day-old male broiler chicks were randomly distributed into eight dietary treatment groups in a three-way ANOVA with 2?×?2?×?2 factorial arrangement (three factors, i.e., NaHCO3, l-arginine?+?vitamin C, and vegetable oil each with two levels, e.g., 0 and 0.1% of NaHCO3 and l-arginine?+?vitamin C; 3 and 4% of vegetable oil supplemented with basal diet) for a period of 35 days. Iso-caloric and iso-nitrogenous diets were formulated and supplied ad libitum. The final live weight (FLW), average daily feed intake (ADFI), average daily gain (ADG), feed efficiency (FE), carcass traits, cardio-pulmonary morphometry, total protein (TP), hemoglobin (Hb), triiodothyronine (T3), incidence of tachycardia, and polycythemia were examined. Supplementation of NaHCO3 increased 2.2% ADFI, 5.5% FE, and 23.2% TP. The l-arginine?+?vitamin C increased 2.4% FLW and decreased 1.9% heart rate. Vegetable oil increased 1.3% ADFI, 4.2% ADG, 8.6% FE, 23.1% Hb, and 15.5% PCV. The NaHCO3, l-arginine?+?vitamin C, and vegetable oil additively interacted to increase 31.5% T3 at the expense of 21.1% of the weight of the right ventricle (RV). The RV:TV, carcass traits, and hemato-biochemical indices remained within normal range irrespective of the levels of the supplementations of the test ingredients. It was concluded that vegetable-based high-energy mash diets were not susceptible to tachycardia and polycythemia. The addition of NaHCO3 and l-arginine?+?vitamin C ameliorated the propensity of tachycardia and polycythemia without deteriorating performance, carcass traits, and hemato-biochemical indices of the broiler chicken in a dose-dependent manner.

  相似文献   
73.
Current study was conducted to identify constituents of Taxus wallichiana Zucc. that might be responsible for its folk use in anti-inflammatory conditions. Taxusabietane A was isolated from the bark extract of Taxus wallichiana Zucc. Taxusabietane A was analyzed for in-vitro and in-vivo anti-inflammatory activities using Lipoxygenase (LOX) inhibition assay and carrageenan-induced paw edema model. Taxusabietane A revealed considerable LOX inhibitory activity with the IC50 value being 57 ± 0.31. Standard compound Baicalein showed the IC50 value being 22.1 ± 0.03 μM. Taxusabietane A also showed significant (5 and 10 mg/kg) anti-inflammatory activity induced by carrageenan. However, this study highlighted the potential of Taxusabietane A to be further explored as a new lead compound for management of conditions associated with inflammation.  相似文献   
74.
Through field studies, cotton responses to dual stresses – waterlogging and low light (shade) were investigated. The hypothesis was that shade would amplify yield losses in waterlogged (WL) cotton. Either early or late in the reproductive phase, the crop was WL (96 h and 120 h, in 2012–2013 and 2013–2014, respectively) and/or shaded (6 days or 9 days in 2012–2013 and 2013–2014, respectively). Waterlogging at early reproductive phase significantly reduced lint yield (17 % averaged across both years) of cotton, although shade‐induced yield losses (18 %) were only significant in 2013–2014. Shade significantly exacerbated yield losses only when the impact of waterlogging damage was modest (2013–2014). More intense waterlogging impaired lint yield independently of the light levels. Yield reductions in these experiments were the consequence of both accelerated fruit abscission and fewer fruiting nodes produced. Plants had lower leaf nitrogen levels and photosynthetic rates after waterlogging and/or shade treatments and produced fewer fruiting nodes. Although long‐term shade increased specific leaf area (30 %) and leaf N (20 %) immediately following 5 days of waterlogging, it did not restore shoot growth, node formation or lint yield because of suppressed photosynthetic performance (area basis) and carbohydrate supply.  相似文献   
75.
The contamination of agriculture soils with heavy metals is increasing due to both natural and anthropogenic activities. This has resulted in lowering the yield and quality of agriculture crops. The aim of the present investigation was to determine the effect of Moringa oleifera (M. oleifera) aqueous leaf extract (MALE) on growth and Hg phytoextraction potential of maize cv. Azam under mercuric chloride (HgCl2)-induced stress. Soil was contaminated with different concentrations of HgCl2 (1 and 0.5?mg/kg). The MALE was applied at 5% and 2.5% as seed soaking prior to sowing of seeds in the pots. The M. oleifera leaf was a good source of macronutrients (Na, K, Ca and Mg) and micronutrients (Fe, Zn, Mn, Co and Ni) as well as natural phenolics. The induced HgCl2 stress significantly reduced seed germination (%), shoot dry weight, root dry weight, chlorophyll content and carotenoids content. The HgCl2-induced stress was associated with accumulation of phenolics and Hg in roots. The accumulation of Hg in roots was significantly correlated with phenolics content (r?=?.8007, p?=?.000). The exogenous application of MALE significantly ameliorated adverse effects of HgCl2 stress on maize plants. The accumulation of Hg in roots was significantly increased by MALE. It is inferred from findings of the present investigation that MALE served as bioregulator and can be applied to reduce adverse effects of HgCl2 on maize. Moreover, MALE can enhance the Hg phytoremediation potential of maize.  相似文献   
76.
77.
Wang  Xuemei  Xu  Kai  Miao  Wenhao  Gao  Linhao  Ullah  Saif  Lyu  Yueming  Wang  Xiangping 《European Journal of Forest Research》2022,141(5):927-938
European Journal of Forest Research - Increasing drought associated with climate warming (i.e., hotter drought) is seriously threatening tree growth and survival across the world. Previous studies...  相似文献   
78.
Knowledge about the extent of genetic diversity/relatedness in mango germplasm is vital for developing coherent strategies for future gains in productivity. The genetic diversity/relatedness among mango cultivars/genotypes developed in Pakistan has not been investigated previously. We have assessed the genetic diversity among 25 mango genotypes/cultivars using randomly amplified polymorphic DNA (RAPD). Sixty random ten-mer primers were surveyed, out of which 45 yielded amplicons in all the genotypes. Genetic similarity between genotypes/cultivars was in the range of 64–89% with an average of 74%. Similarly, the genetic relatedness among all variants derived from a mango cultivar Chaunsa was in the range of 81.18–88.63%. These coefficients were utilized to construct a dendrogram using the unweighted pair group of arithmetic means (UPGMA). The genotypes were grouped into three (A, B, C) clusters. Generally, genotypes originating from Pakistan were grouped in cluster ‘A’ while cluster ‘B’ primarily composed of southern India as well as Florida cultivars. Kensington Pride was the most distantly related genotype which grouped with Maya and Yakta, forming a distinct cluster ‘C’.  相似文献   
79.
Tyrosine hydroxylase (TH) is the rate-limiting enzyme of dopamine (DA) biosynthesis, which is up-regulated by vitamin C administration. Nurr1 gene is highly expressed in brain and important for midbrain DAergic cell development and survival. But, the role of vitamin C and/or vitamin E during Nurr1 expression is yet to be known. Further, the synergistic effect of vitamins C and E on TH expression has not yet been explored clinically. Therefore, we studied the effects of single or co- administration of vitamin C (0.5 mM) and vitamin E (1 mM) for 72 hr, on both TH and Nurr1 expression in in vitro primary cultured gestational days (GD) 13.5 rat ventral mesencephalon (VM) by Western blot and immunocytochemistry. Our study revealed highest expressions of both TH and Nurr1 in the vitamin C + vitamin E treated group. TH expression was also increased in the vitamin C treated group than that of the control group, but the vitamin E treated group did not show any statistically significant effect. However, both the vitamin C and the vitamin E treated groups revealed increased expression of Nurr1 protein as compared with the control group. The present experimental data suggest that vitamin C can up-regulate the protein expression of TH, but Nurr1 level was elevated either by vitamin C or by vitamin E administration. Further, vitamin E acts synergistically with vitamin C to elevate TH and Nurr1 expression, which is the most novel finding of our study and for the first time; we reported this result, since there have been no published data on the synergistic effect of both the antioxidant vitamins on TH and Nurr1 expression in VM. As the motor function defect due to the progressive loss of DAergic neuron is the major reason of Parkinsonism, therefore, the results of our study finally suggest the effective role of vitamin C and vitamin E during early treatment of Parkinsonism.  相似文献   
80.
The aim of the study was to investigate the location of motor neuron somata of geniohyoid muscle in rat. Nine Sprague‐Dawley rats were used in this study. Operations were performed under general anaesthesia. Nembutal sodium, 40 mg per kg intraperitoneally was used for anaesthesia. 0.02 to 0.05 ml of 30% horseradish peroxidase (Sigma Type VI) solution in normal saline was injected into the exposed right geniohyoid muscle. After 48 hr, the animals were fixed by perfusion through left ventricle of heart, first by 100 ml normal saline and then with 500 ml of 1.25% glutaraldehyde and 1% paraformaldehyde in 0.1 M phosphate buffer, pH 7.4, at room temperature, and finally with 500 ml of 10% sucrose in the same buffer at 4°C. The medulla oblongata and first cervical segment of spinal cord were removed, kept in 10% sucrose in above phosphate buffer at 4°C for 24 hr. Thereafter, their serial transverse sections were cut in a cryostat at a thickness of 60 μm. The sections were treated according to tetramethyl benzidine (TMB)‐horseradish peroxidase (HRP) method. HRP‐labelled neuron somata were observed at the following sites: (a) In ventral part of right main hypoglossal nucleus in upper two‐thirds of the closed part of medulla oblongata. (b) In ventrolateral subnucleus of hypoglossal nucleus in lower third of closed part of medulla oblongata. (c) At spinomedullary junction, they were located in dorsomedial part of right ventral grey column; a few were also seen here scattered on right side of central canal and among corticospinal fibres.  相似文献   
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