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排序方式: 共有594条查询结果,搜索用时 15 毫秒
21.
New Forests - Climate change is predicted to cause northward migration of boreal tree species. However, the success of such a migration will be determined by trees’ ability to acclimate to... 相似文献
22.
Indigenous communities in the Chittagong Hill Tracts (CHT) of Bangladesh had been conserving small patch of forests, commonly called village common forests (VCFs), especially for drinking water and non-timber forest produce. The size of VCFs has been decreasing, due to increasing population and conversion of forests for shifting cultivation. To restore the degraded forest resources and conserve the forest ecosystems in the VCF of the CHT, an intervention was undertaken in Bandarban, Bangladesh by Arannayk Foundation, an organization established jointly by the Government of Bangladesh and the United States of America. A training program on leadership, organizational development and alternative income generating activities was implemented to build the capacity of the members of the VCF management committee. The impact of the interventions was measured at the end of third year. Incomes of VCF-dependent communities were found to increase with resultant reduction of their dependence on VCFs. The intervention encouraged women’s participation in forest management and facilitated a written format of the constitution of the VCF management. The study identified that more training and awareness-raising activities are needed to ensure sustainability of the interventions. Mobilizing funds for the communities for sustainable alternative livelihoods was found effective. Appropriate compensation for conservation was found to make the restoration and conservation activities sustainable. 相似文献
23.
Research was conducted in Alutilla Valley in eastern Bangladesh to identify the nature of existing agroforestry systems and to identify potential agroforestry models that could ameliorate currently degrading forest resources Data were collected through farmer participatory research and a structured quarterly survey in two villages. Qualitative and supplementary quantitative analysis methods were used to assess the financial potential of agroforestry systems. Various patterns of agroforestry exist in the study site, but all have two common principles, namely ‘integration with agriculture’ and ‘multi-functionality’. Two agroforestry models suitable for adoption by farmers have been identified. Multi-strata agroforestry, based on a fruit and timber tree canopy with vegetables and tuber species in the understorey, can be practiced in the shifting cultivation fields near settlements. Fruit and timber tree-based conservation agroforestry is well suited to manage large-scale biologically depleted landscapes. Both systems yield early financial returns, facilitating the change from shifting cultivation to multi-strata agroforestry or fruit and tree-based conservation agroforestry. 相似文献
24.
Shin-Ichi Teshima Shunsuke Koshio Manabu Ishikawa Md. Shah Alam Luis Hector Hernandez Hernandez 《Journal of the World Aquaculture Society》2006,37(2):145-153
The dietary protein requirement of the freshwater prawn Macrobrachium rosenbergii to obtain the maximum body protein retention was assessed by the estimated protein needed daily for maintenance (M) and body protein increment (G). The body protein increment was estimated by quantifying body nitrogen increments when the prawn was fed high‐protein diets composed primarily of casein. The protein required for maintenance was estimated by regressing weight gains in feeding experiments using graded dietary levels of casein. The true daily retention (R) or increase in body protein of the prawn corresponds to the sum of M and G. The values of M, G, and R determined in the present study were 3.86, 0.24, and 4.10 g/kg body weight/d, respectively. On the basis of the daily body protein increment and the net protein utilization of casein (58%), dietary protein requirement of the juvenile M. rosenbergii for maximum body protein retention was suggested to be about 7.1 g/kg body weight/d. 相似文献
25.
Das Gour Gobindo Malek Md. Abdul Shamsuddin A. K. M. Sagor G. H. M. 《Genetic Resources and Crop Evolution》2022,69(3):1009-1018
Genetic Resources and Crop Evolution - Brassica napus L is an important oilseed crops grown throughout many parts of the world. It is well adapted to long day photoperiods. Synthetic B. napus was... 相似文献
26.
Rakib MA Kim YS Jang WJ Choi BD Kim JO Kong IK Ha YL 《Journal of agricultural and food chemistry》2010,58(22):12022-12030
The protective effect of c9,t11-conjugated linoleic acid (CLA) on the inhibition of gap junctional intercellular communication (GJIC) was examined in a human mammary epithelial cell line (MCF-10A) treated with 12-O-tetradecanoylphorbol-13-acetate (TPA), relative to t10,c12-CLA isomer. TPA inhibited GJIC in a dose-dependent and reversible manner and was associated with connexin 43 phosphorylation. Pretreatment of 20 μM c9,t11-CLA for 24 h prior to 60 nM TPA for 1 h prevented the inhibition of GJIC by reducing the phosphorylation of connexin 43 via suppressing extracellular signal-regulated kinases (ERK1/2) activation. Reactive oxygen species (ROS) accumulation by TPA was attenuated by c9,t11-CLA. The efficacy of c9,t11-CLA in protecting inhibition of GJIC, connexin 43 phosphorylation, and ROS production was superior to that of t10,c12-CLA. These results suggest that c9,t11-CLA, including t10,c12-CLA, prevents the carcinogenesis of MCF-10A cells by protecting down-regulation of GJIC during the cancer promotion stage, and lack of their toxicities could be an excellent indicator for the chemoprevention of breast cancer. 相似文献
27.
28.
Nazmul H. ANTOR Shamim MIA Md. M. HASAN Nowrose J. LIPI Keiji JINDO Miguel A. SANCHEZ-MONEDERO Md. H. RASHID 《土壤圈》2023,33(4):659-669
Biochar is considered a potential technology to enhance chemical fertilizer use efficiency through intensification of the interactions between nutrients and the functional groups on biochar surfaces. However, little is known about how the application of activated biochars mixed with urea influences nitrogen(N) mineralization and crop performance in paddy fields. Here, a sawdust-derived fresh biochar (FBC)(ca. 400?C) was activated chemically with 15%hydrogen peroxide and biologically with a nutri... 相似文献
29.
Md Romij Uddin Leonard John Wade Jong Yeong Pyon Md Abdul Mazid 《Journal of Crop Science and Biotechnology》2009,12(1):17-23
An experiment was carried out at the Agronomy Field Laboratory, Bangladesh Agricultural University (BAU), Mymensingh in Old
Brahmaputra Alluvial Flood Plain (AEZ-9) during December 2005 to May 2006 to examine the root growth of different rice cultivars
under various establishment methods. This experiment comprised two sets of treatment (i) three methods of planting viz., dry
direct seeding, wet direct seeding and transplanting, and (ii) six rice cultivars, two inbreds viz., BRRI Dhan 28 and BRRI
Dhan 29, two hybrids, viz., Aalok 6201 and Sonarbangla 1 and two local improved cultivar viz., Habigonj IV and Habigonj VIII.
Cultivars had more remarkable effect on different root parameters i.e. number of roots, root length, root length density,
root biomass, root weight ratio and root shoot ratio of hybrid, inbred and local improved rice cultivars than method of planting.
BRRI Dhan 28 performed the best for most of the parameters. At harvest, BRRI Dhan 29 showed the best rooting behavior among
the cultivars. For both stages hybrid rice cultivars showed intermediate and local improved cultivars performed lower in rooting
behavior. Direct seeding method performed better than transplanting method for most of the root parameters but wet direct
seeding and dry direct seeding methods were identical. Interaction effect between method of planting and cultivar in most
of the root parameters were insignificant. But, BRRI Dhan 28 and BRRI Dhan 29 under wet direct seeding method and Sonarbanngla
1 under transplanting method showed the best rooting performance among the other combinations. 相似文献
30.
Mohammed F. Aldawsari Mohammed Muqtader Ahmed Farhat Fatima Md. Khalid Anwer Prakash Katakam Abdullah Khan 《Marine drugs》2021,19(8)
The objective of this work was to develop sustained-release Ca-alginate beads of apigenin using sodium alginate, a natural polysaccharide. Six batches were prepared by applying the ionotropic gelation technique, wherein calcium chloride was used as a crosslinking agent. The beads were evaluated for particle size, drug loading, percentage yield, and in vitro drug release. Particle size was found to decrease, and drug entrapment efficiency was enhanced with an increase in the polymer concentration. The dissolution study showed sustained drug release from the apigenin-loaded alginate beads with an increase in the polymer proportion. Based on the dissolution profiles, BD6 formulation was optimized and characterized for FTIR, DSC, XRD, and SEM, results of which indicated successful development of apigenin-loaded Ca alginate beads. MTT assay demonstrated a potential anticancer effect against the breast cancer MCF-7 cell lines. The antimicrobial activity exhibited effective inhibition in the bacterial and fungal growth rate. The DPPH measurement revealed that the formulation had substantial antioxidant activity, with EC50 value slightly lowered compared to pure apigenin. A stability study demonstrated that the BD6 was stable with similar (f2) drug release profiles in harsh condition. In conclusion, alginate-based beads could be used for sustaining the drug release of poorly water-soluble apigenin while also improving in vitro antitumor, antimicrobial, and antioxidant activity. 相似文献