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11.
Jan  Sami  Khan  M. N.  Jan  Sofora  Zaffar  Aaqif  Rashid  Rizwan  Khan  M. A.  Sheikh  F. A.  Bhat  M. Ashraf  Mir  R. R. 《Genetic Resources and Crop Evolution》2022,69(2):661-676
Genetic Resources and Crop Evolution - Barley (Hordeum vulgare L.) is one of the principal cereal crops grown in Western-Himalayas of India. A set of 105 barley genotypes including 38...  相似文献   
12.
  1. The ocean crisis is urgent and central to human wellbeing and life on Earth; past and current activities are damaging the planet's main life support system for future generations. We are witnessing an increase in ocean heat, disturbance, acidification, bio‐invasions and nutrients, and reducing oxygen levels. Several of these act like ratchets: once detrimental or negative changes have occurred, they may lock in place and may not be reversible, especially at gross ecological and ocean process scales.
  2. Each change may represent a loss to humanity of resources, ecosystem function, oxygen production and species. The longer we pursue unsuitable actions, the more we close the path to recovery and better ocean health and greater benefits for humanity in the future.
  3. We stand at a critical juncture and have identified eight priority issues that need to be addressed in unison to help avert a potential ecological disaster in the global ocean. They form a purposely ambitious agenda for global governance and are aimed at informing decision‐makers at a high level. They should also be of interest to the general public.
  4. Of all the themes, the highest priority is to rigorously address global warming and limit surface temperature rise to 1.5°C by 2100, as warming is the pre‐eminent factor driving change in the ocean. The other themes are establishing a robust and comprehensive High Seas Treaty, enforcing existing standards for Marine Protected Areas and expanding their coverage, especially in terms of high levels of protection, adopting a precautionary pause on deep‐sea mining, ending overfishing and destructive fishing practices, radically reducing marine pollution, putting in place a financing mechanism for ocean management and protection, and lastly, scaling up science/data gathering and facilitating data sharing.
  5. By implementing all eight measures in unison, as a coordinated strategy, we can build resilience to climate change, help sustain fisheries productivity, particularly for low‐income countries dependent on fisheries, protect coasts (e.g. via soft‐engineering/habitat‐based approaches), promote mitigation (e.g. carbon storage) and enable improved adaptation to rapid global change.
  相似文献   
13.
The antitumor activity of the ethanolic extracts of 12 medicinal plants of Bangladesh, including the vincristine-vinblastine producing Catharanthus roseus was studied using the potato disk bioassay technique. Among these, 10 plant extracts at 25.0-microgram/disc exhibited significant inhibition of crown gall tumors caused by Agrobacterium tumefaciens.  相似文献   
14.
The present study was conducted to identify natural products in the bioactive fractions of Lagenaria siceraria mesocarp. Column chromatography and gas chromatography-mass spectrometry (GC-MS) was used for separation and identification of phytochemicals. Methanolic extract and its fractions displayed alpha-amylase and xanthine oxidase inhibitory activities comparable to standard drugs. GC-MS analysis of the fractions and column eluates revealed the presence of a variety of chemical compounds, including 4-(methoxymethyl)phenol, 2,2?-methylenebis{6(1,1-dimethylethyl)-4-ethyl}phenol, methyl 2-hydroxy-3-phenylpropanoate, oxacyclododecane-2,8-dione, N-(2-(4-hydroxyphenyl)ethyl] acetamide, 2,3-Epoxycarane, 4-(propan-2-yl)benzaldehyde, octadec-1-ene, 4a-methyl-1-methylidene-1,2,3,4,4a,9,10,10a-octahydrophenanthrene, 2,6-di(propan-2-yl)naphthalene, methyl 3-(4-hydroxy-3,5-dimethylphenyl)propanoate, 4,8a-dimethyl-6-(prop-1-en-2-yl)-3,5,6,7,8,8a-hexahydronaphthalen-2(1H)-one 1,3-dihydro-2-benzofuran, methyl N-hydroxybenzenecarboximidoate, linoleic acid, and palmitic acid. Many of these compounds are being reported for the first time from this plant, the presence of which may explain, at least partly, its medicinal efficacy. The fruit possesses significant anti-enzymatic properties against alpha-amylase and xanthine oxidase, and the most active compounds of mesocarp of the fruit appear in ethyl acetate fraction of its methanolic extract.  相似文献   
15.
A pot experiment was conducted to evaluate the foliar applied phosphorous with and without pre-plant dose (50 kg hac.?1) of phosphorous on growth, chlorophyll contents, gas exchange parameters and phosphorous use efficiency (PUE) of wheat. The experiment was conducted in net house at Department of Crop Physiology, University of Agriculture Faisalabad, Pakistan. Two promising wheat cultivar AARI 2011 and FSD 2008 were used as a test crop with 5 foliar phosphorus (P) rates (0, 2, 4, 6, 8 kg ha?1). The foliar applied P with pre-plant performed better than without pre-plant and control treatments. Foliar treatment of phosphorus at 6 kg ha?1 P proved to be the best among other foliar treatments followed by 8 kg ha?1 P. The foliar application of phosphorous at 6 kg hac.?1 with pre-plant soil applied P increased the shoot length, root length, shoot fresh weight, root fresh weight, shoot dry weight and root dry weight. The chlorophyll contents (Chl. a and b) were increased with the foliar application of phosphorous. The gas exchange parameters (net carbon dioxide (CO2) assimilation rate, transpiration rate, stomatal conductance and sub-stomatal CO2 rate) were significantly improved by foliar applied P. The maximum values of net CO2 assimilation rate (5.27 μ mol m?2 sec.?1), transpiration rate (3.44 μ mol m?2 sec.?1), stomatal conductance (0.81 μ mol m?2 sec.?1) and sub-stomatal CO2 (271.67 μ mol m?2 sec.?1), were recorded in the treatment where P was foliar applied at 6 kg hac.?1 with pre-plant soil applied Phosphorous. The foliar application of phosphorous with pre-plant soil applied P enhanced Phosphorous use efficiency (PUE) in both varieties. The maximum value of PUE (15.42%) was recorded in the treatment where foliar feeding of P was done at 6 kg hac.?1 with pre-plant soil applied P in both genotypes.  相似文献   
16.
Cr(III) ions sorption onto sawdust of spruce (Picea smithiana) has been studied thoroughly using radiotracer technique. Maximum sorption (94%) of Cr(III) ions (8.98×10?5 M) onto sorbent surface is achieved from deionized water in 20 min agitation time using 200 mg of sawdust. The sorption data followed the Freundlich, Dubinin-Radushkevich (D-R) and Langmuir isotherms. Freundlich constants l/n = 0.86 ± 0.07 and C e = 85.0 ± 25.8 mmole g?1 have been estimated. Sorption capacity, X m = 0.82± 0.3 mmole g?1, β = ?0.00356± 0.00017 kJ2 mole?2 and energy, E = 11.9± 0.3 kJ mole?1 have been evaluated using D-R isotherm. The Langmuir constants Q = 5.8± 0.2 μmole g?1 and b = (7.4± 0.5)×104 dm3 mole?1 have been calculated. The variation of sorption with temperature yields thermodynamic parameters Δ H = ?11.6± 0.3 kJ mole?1, Δ S = ?16.2± 0.9 J mole?1 K?1 and Δ G = ?6.8± 0.3 kJ mole?1 at 298 K. The negative value of enthalpy and free energy reflect the exothermic and spontaneous nature of sorption respectively. Among the anions studied oxalate, citrate, carbonate and borate have reduced the sorption. The cations Y(III), Ce(II) and Ca(II) suppressed sorption. The sawdust column can be used to separate Cr(III) ion from Cs(I), I(I),Tc (VII) and Se (IV).  相似文献   
17.
Toxic and protective constituents in pet foods   总被引:1,自引:0,他引:1  
An analytical survey of mutagens, nitrosamines, polychlorinated biphenyls, toxic elements, and gamma-emission, as well as the toxicologically protective constituents zinc, selenium, and vitamin C, in 48 pet foods was conducted. Aside from high concentrations of fluoride and iodide in some samples and the expectedly higher concentrations of mercury and selenium in certain cat foods containing fish, the samples were notably free of the other toxic constituents. Direct-acting and promutagens and nitrosamines were not detectable in any of the samples. gamma-Emission was very low in all of the foods. Polychlorinated biphenyls were only detected in one cat food.  相似文献   
18.
Leaf blades, petioles, corms and cormels of 9 cultivars of edible aroids were analyzed to determine the content of protein, carbohydrate, crude fibre, ether extract, ash, carotene, thiamine, riboflavin, ascorbic acid, iron, calcium and phosphorus. The cultivars represent the genera Colocasia, Xanthosoma, Alocasia and Amorphophallus. Wide differences among the cultivars in respect of almost all of the components of analysis were observed.  相似文献   
19.
20.
Establishment of Protected Areas (PAs), in the face of rapid deforestation, forest degradation and climate change has been one of the key efforts in conservation of biodiversity worldwide in recent times. While Bangladesh has gained a degree of prominence in the world for its successful social forestry programs, the concept of collaborative protected area management is rather new in the country, initiated in 2004 by the Bangladesh Forest Department in five PAs with financial assistance from USAID. Based on empirical evidence from three of the pilot PAs, we examined the achievements and associated challenges and prospects for co-management. Our fieldwork revealed a number of challenges faced by co-management institutions: (1) institutions were dominated by the elite group, overshadowing the voice of the community people; (2) mutual trust and collective performance are key to good governance but had not taken root in the PAs; (3) encroachment onto forest land and subsequent conversion to agriculture remained a serious problem that discouraged forest-dependent people from participating actively in co-management initiatives; (4) legal provisions (including acts, rules and policies) were not clearly and adequately disseminated and understood at the community level; (5) there remained a degree of ambiguity regarding the roles and responsibilities of forest department (FD) and co-management committees (CMC) in field operations, and this was not enhancing transparency and accountability of the overall initiative; (6) the long-term sustainability of co-management institutions was another major concern, as the local intuitional structure was still in a nascent stage, and provisioning of resources (either internally or externally) remained somewhat uncertain. We offer recommendations for improvement.  相似文献   
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