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11.
Samir C. Debnath Kenneth B. Mcrae 《The Journal of Horticultural Science and Biotechnology》2013,88(6):744-752
SummaryAn efficient system to regenerate shoots in vitro on excised leaves of lingonberry (Vaccinium vitis-idaea L.) was developed. Leaf explants from shoot-proliferating cultures produced multiple shoots without an intermediary callus phase on zeatin (ZN)-containing shoot induction media within 3–4 weeks of culture initiation. Cultivars Regal and Splendor, and one clone from a natural stand in Estonia (ECL1), were used in the first experiment. Young expanding leaves with the adaxial side touching the culture medium, and maintained for 7 d in darkness, produced the best results. There were significant genotypic differences in adventitious shoot formation. A second experiment studied the effects of ten concentrations of three cytokinins: ZN at 5, 10, 20, 30 and 40 μM; 1-phenyl-3-(1,2,3-thiadiazol-5-yl) urea (thidiazuron, TDZ) at 0.1, 1, 5 and 10 μm; and 6-(γ-γ-dimethylallylamino) purine (2ip) at 25 μM were compared with leaf segments of different polarity in ‘ECL1’. Zeatin was found to be more effective than TDZ or 2iP as an inductive signal for regenerating many vigorous shoots. Zeatin induced multiple shoot formation at all concentrations tested, but maximum morphogenic response was observed at 20 to 30 μM. The media containing TDZ generally promoted more callus formation and suppresed shoot elongation. In a third experiment with the lingonberry cultivar Erntedank and the clone ‘ECL1’, a new medium developed for lingonberry shoot culture proved more effective than the modified Murashige and Skoog medium for regenerating shoots on leaf explants. Elongated shoots were excised and rooted directly on a 2 peat:1 perlite (v/v) medium after dipping in 0.8% indole-3-butyric acid. Rooted plantlets were acclimatized under greenhouse conditions to evaluate somaclonal variation. 相似文献
12.
Bikas C. Debnath Purnendu Biswas Barun Roy 《Journal of animal physiology and animal nutrition》2019,103(1):29-40
Three hundred thirty‐day‐old unsexed commercial broiler chicks (Vencobb‐400) with initial average body weight of 44.04 ± 0.42 g were allocated into five experimental groups, in a completely randomized design (CRD) with 21‐day experiment. Groups were formed according to dose of supplemental L‐threonine in various rations i.e., 100% NRC specification, 100% threonine of Vencobb‐400 strain specification, 110% threonine of Vencobb‐400 strain specification, 120% of threonine of Vencobb‐400 strain specification and 130% threonine of Vencobb‐400 strain specification. Average daily feed intake (ADFI), average daily body weight gain (ADG), cumulative feed conversion ratio (CFCR), carcass characteristics, immune response, intestinal morphometry and biochemical profile were studied. The ADFI and ADG increased linearly and quadratically as dietary threonine levels were increased. However, the CFCR did not differ (p ? 0.05) among the groups. Though the carcass weight and drumstick yield did not differ (p ? 0.05) among the groups, the relative breast yield increased linearly (p = 0.007). The relative dressing yield and relative thigh weight increased linearly (p = 0.05 and p = 0.03, respectively). The relative weight of immune organs like bursa and thymus increased linearly. The mean total serum immunoglobulin, ND‐ELISA titre and the mean lymphocyte proliferation response index increased linearly, whereas mean phagocytic activity index of neutrophil increased linearly (p < 0.001) and quadratically (p = 0.001). The mean villus height (VH), crypt depth (CD), villus surface area and mean goblet cell number/villus increased linearly and quadratically, whereas the villus width (VW) and goblet cell density increased quadratically. The serum glucose increased linearly (p = 0.001), whereas serum total protein concentration and serum globulin level increased both linearly and quadratically. The albumin: globulin ratio tended to decrease linearly. There was a significant decrease (p < 0.05) in serum cholesterol and VLDL cholesterol level. However, a linear increment (p = 0.04) in the blood serum HDL cholesterol level with a linear reduction (p = 0.01) in the blood serum LDL cholesterol was noticed. 相似文献
13.
SK Shaheenur Islam Holy Akwar Md. Mehedi Hossain Md. Abu Sufian Md. Zakiul Hasan Shovon Chakma Tongkorn Meeyam Warangkhana Chaisowwong Veerasak Punyapornwithaya Nitish C. Debnath Eric Brum Duangporn Pichpol 《Zoonoses and public health》2020,67(6):658-672
Analysis of environmental samples obtained from the Live Poultry Markets (LPMs) of Dhaka City, Bangladesh, has revealed that the highest degree of prevalence of highly pathogenic avian influenza A (HPAI, H5N1), besides other subtypes of the LPAI virus, poses the plausible risk of transmission of these viruses between human and poultry species. The present study was conducted using the OIE risk analysis framework to assess the risk level of each pathway successively. The estimated risk parameters were integrated towards to obtain the overall risk level for each specific HPAI transmission pathway using the matrix adapted by Cristobel Zepeda accompanying other expert consultations. The relevant data obtained from published and unpublished sources, together with survey data of field observations, were used to formulate and confirm the risk pathways and their associated risks. The results revealed that the risk of the release of the HPAI virus was medium when exposure was high. Additionally, the consequence would be considered very high with a medium degree of uncertainty for all parameters. Ultimately, the overall risk for transmission was estimated as medium with a medium degree of uncertainty. The findings of this study reveal that there is a significant threat that HPAI virus transmission could occur among poultry and humans and effectively sustain within the environment of the LPMs. Our findings are primarily focused on public health considerations, the hygienic slaughter of poultry and the relevant cleaning and sanitation practices conducted in the LPMs to support evidence‐based decision‐making processes. The findings of the study have the potential to be used to formulate effective risk reduction measures and can be further adapted in low‐resource settings without major infrastructural changes required of the LPMs. All of which would reduce the risk of HPAI virus release and further lessen the degree of exposure and transmission in established LPMs. 相似文献
14.
McNamara C Zinkernagel AS Macheboeuf P Cunningham MW Nizet V Ghosh P 《Science (New York, N.Y.)》2008,319(5868):1405-1408
Antigenically variable M proteins are major virulence factors and immunogens of the human pathogen group A Streptococcus (GAS). Here, we report the approximately 3 angstrom resolution structure of a GAS M1 fragment containing the regions responsible for eliciting type-specific, protective immunity and for binding fibrinogen, which promotes M1 proinflammatory and antiphagocytic functions. The structure revealed substantial irregularities and instabilities throughout the coiled coil of the M1 fragment. Similar structural irregularities occur in myosin and tropomyosin, explaining the patterns of cross-reactivity seen in autoimmune sequelae of GAS infection. Sequence idealization of a large segment of the M1 coiled coil enhanced stability but diminished fibrinogen binding, proinflammatory effects, and antibody cross-reactivity, whereas it left protective immunogenicity undiminished. Idealized M proteins appear to have promise as vaccine immunogens. 相似文献
15.
Ghosh Uday Chand Dasgupta Manotosh Debnath Sushanta Bhat Subhas Chandra 《Water, air, and soil pollution》2003,143(1-4):245-256
The anion exchange behaviour of hydrous titanium oxide(HTO) has been exploited for the management of industrialwaste effluents contaminated with chromium(VI). Theadsorption of chromium(VI) by HTO (74.0–140.0 micron) in thepH range 0.5–8.0 has been studied. It is found that theadsorption of chromium(VI) by HTO is at a maximum in the pHrange 1.5–2.0. The interference of diverse foreign ionssuch as nitrate, chloride, sulfate, phosphate, calcium,magnesium, nickel, iron(III), barium etc. on the adsorptionof chromium(VI) by HTO at optimum pH has been investigatedby a batch-operation technique. Break-through capacity,adsorption and elution of chromium(VI) using HTO have beenstudied. It is found that HTO could be reused as anadsorbent for chromium(VI). Finally, chromium(VI) wasrecovered as insoluble chromate compound from waste effluentof Hindustan Motor Limited (HML) of Hooghly, West Bengal, India. 相似文献
16.
S. C. Debnath 《Genetic Resources and Crop Evolution》2007,54(3):509-517
Forty-three wild cranberry (Vaccinium macrocarpon Ait.) clones collected from four Canadian provinces and five cranberry cultivars were assessed for genetic variability by
using random amplified polymorphic DNA (RAPD)-PCR. Fourteen primers generated 161 polymorphic RAPD-PCR bands. A substantial
degree of genetic diversity was found among the wild cranberry collections. Cluster analysis by the unweighted pair-group
method with arithmetic averages (UPGMA) separated the wild clones and three cultivars into five main clusters, and identified
the two remaining cultivars as outliers. Furthermore, within four clusters, the genotypes tended to form sub-clusters that
were in agreement with the principal coordinate (PCO) analysis. Geographical distribution explained 10% of total variation
as revealed by analysis of molecular variance (AMOVA). The RAPD markers detected a sufficient degree of polymorphism to differentiate
among cranberry clones and cultivars, making this technology valuable for germplasm management and the more efficient choice
of parents in current cranberry breeding programs. 相似文献
17.
Kartik Baruah Asim K. Pal Narottam P. Sahu Dipesh Debnath Parisa Nourozitallab Patrick Sorgeloos 《Journal of the World Aquaculture Society》2007,38(1):129-137
Abstract.— A feeding trial was conducted for 60 d to study the effect of dietary microbial phytase on growth performance and nutrient digestibility of rohu, Labeo rohita , fingerlings. One hundred and twenty fingerlings (average initial weight: 9.17 g/fish) were equally distributed into five experimental tanks, each with four replicates. Five isonitrogenous (35%) and isocaloric (16.79 kJ/g) diets were prepared from plant-based ingredients, supplemented with microbial phytase at the level of 0, 250, 500, 750, and 1000 U/kg diets and fed to T0 , T1 , T2 , T3 , and T4 groups, respectively. Weight gain %, food conversion ratio, protein efficiency ratio, and apparent net protein utilization were significantly ( P < 0.05) improved in groups fed phytase-supplemented diets compared to control, the highest being observed in T3 group. Maximum apparent digestibility of phosphorus and crude protein was recorded in T3 group. Bone ash, phosphorus (P), and calcium (Ca) contents were also significantly ( P < 0.05) increased in phytase-fed groups. However, maximum was recorded in T3 group. Results from the present study indicated that addition of 750 U microbial phytase/kg diets effectively improved nutrient utilization, bone mineralization, and hence growth of L. rohita fingerlings. 相似文献
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19.
Mitra Surabhi Debnath Prasenjit Rai Richa Srivastava Nishant Rao Govind Pratap Baranwal Virendra Kumar 《European journal of plant pathology / European Foundation for Plant Pathology》2022,163(4):907-922
European Journal of Plant Pathology - Symptoms of bunchy top, little leaf, leaf chlorosis with chlorotic streaks, leaf necrosis and stunted growth were noticed in two banana cultivars, Champa and... 相似文献
20.
Panda Priyam Debnath Prasenjit Mall Smriti Nigam Amrita Rao Govind Pratap 《European journal of plant pathology / European Foundation for Plant Pathology》2021,161(2):313-330
European Journal of Plant Pathology - During the winters of 2018 to 2020, witches’ broom, phyllody, flat stem, little leaf, yellowing and stunting symptoms were recorded in Mexican... 相似文献