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11.
Embryonic and larval developments of brackish water catfish,Mystus gulio (Hamilton and Buchanan, 1822) induced with human chorionic gonadotropin and consequent larval rearing 下载免费PDF全文
Prem Kumar Gouranga Biswas Tapas Kumar Ghoshal Muniyandi Kailasam Koyadan Kizhakedath Vijayan 《Aquaculture Research》2018,49(7):2466-2476
Mystus gulio, the long whiskers catfish, is a popular food fish and potential candidate species for aquaculture in Sundarban area of India and Bangladesh. Recently, catch of this species has declined due to overfishing and various ecological changes. In the present study, mature fish was induced to spawn in captivity through intramuscular injection of human chorionic gonadotropin at the doses of 10 IU/g to female and 5 IU/g to male. Photomicrographs of all developmental stages of live embryo and larvae were documented with the aid of a light microscope. Results demonstrated that morula, blastula, gastrula and neurula and organogenesis ended at 1:30‐, 3:00‐, 5:30‐, 7:30‐ and 17:15‐hour post‐spawning (hps) respectively. Heartbeat and muscular contraction of embryo commenced at 8:30 and 11.15 hps respectively. Hatching of embryo started after an incubation period of 17:30 hour at an ambient temperature of 29 ± 1°C. The newly hatched larvae measured 2.17 ± 0.29 mm in total length with a yolk volume of 0.165 ± 0.03 mm3 started feeding 36 hr after hatching. The present study, on induced breeding and chronological development of M. gulio embryo, will have significant implications on conservation and seed production for aquaculture. 相似文献
12.
Michelle Wen San Lim Kar Mem Tan Lye Yee Chew Kin Weng Kong 《Journal Of Aquatic Food Product Technology》2018,27(4):446-463
Two-level full factorial design was employed to identify the extraction parameters that can improve the derivation of fucoxanthin content (FC), total carotenoid content (TCC), and antioxidant from two brown seaweeds, Sargassum siliquosum (SS) and Sargassum polycystum (SP). These parameters included temperature (A: 4–45°C), time (B: 30–1,440 min), and solvent-to-solid ratio (C: 10–50 ml/g). Antioxidant activities were determined as trolox equivalent antioxidant capacity (TEAC), 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity, and ferric-reducing antioxidant power (FRAP). Results showed that all three factors were significant (p < 0.05) in providing higher FC in both species. These factors were also significant in obtaining higher TCC in SS; whereas in SP, TCC was only affected by solvent-to-solid ratio. Only temperature was found to contribute significantly to a higher TEAC in both species. However, none of the factors improved DPPH for SS, except temperature and time for SP. For SS, only time was significant in obtaining higher FRAP; whereas temperature and time were significant for SP. Hence, results indicate that a simple modification in the extraction temperature, time, and solvent-to-solid ratio will be able to improve the derivation of fucoxanthin, carotenoids, and antioxidant activities. 相似文献
13.
R. N. Mandal S. Kar D. N. Chattopadhyay J. Maity B. N. Paul P. P. Chakrabarti 《Journal Of Applied Aquaculture》2013,25(2):70-75
ABSTRACTTubifex (Tubifex tubifex) was cultured in captivity using three different wastes: rice mill sludge (RMS), dairy sludge (DS), and raw cattle dung (RCD). Three experiments were conducted: 10, 20, and 30 days. A total of 100 g of tubifex at 62.5 g m?2 was inoculated in 1.6 m2 fiberglass-reinforced plastic tanks. Comparing all production parameters, RMS > DS > RCD. Growth rate (g m?2 d?1) did not differ among durations. RMS- and DS-fed tubifex contained higher protein and fat than RCD-fed tubifex. Efficiency on production of g tubifex per kg of waste material was highest at 10 days, declining with time for all waste materials. This experiment suggests that RMS and DS are effective wastes for tubifex culture, with total production increasing with no reduction in growth rate through 30 days, but with efficiency declining after 10 days. 相似文献
14.
Little work has been done in the past on how clothing thermal and moisture transport properties affect human comfort sensations
during different periods of an exercise. In this work, by correlating the thermal and moisture transport properties of T-shirt
fabrics and garments with the comfort sensations during different stages of exercises, we found that thickness, thermal insulation
and warm/cool feeling of the T-shirt fabrics are important to warmth sensation, skin wetness sensation and overall comfort
throughout the entire period of exercise and immediately after the exercise. Water vapor transmission properties of T-shirt
fabrics or garments are not important to comfort sensations at the start of the exercise, but become an important factor to
comfort sensations in the middle of the exercise up to the resting period after the running exercise, probably due to the
fact that sweating occurs during these periods. Fabric water absorption and air permeability are not significant factors at
the start and during the exercise, but are important after exercise, probably because these properties determine how quickly
the skin can be dried after sweating. 相似文献
15.
Katarzyna Sosnowska Teresa Cegielska-Taras Alina Liersch Wojciech M. Karłowski Jan Bocianowski Laurencja Szała Katarzyna Mikołajczyk Wiesława Popławska 《Euphytica》2017,213(9):212
The allopolyploidization event that created cultivated oilseed rape Brassica napus L, followed by intense breeding, reduced its genetic diversity. Resynthesized (RS) B. napus L. obtained by interspecific hybridization between genotypes of B. rapa L. and B. oleracea L. can be a valuable source for broadening genetic diversity in cultivated oilseed rape. In this study, we determined the extent of DNA polymorphism among natural accessions of oilseed rape, resynthesized B. napus, their parental species and double-low quality semi-RS lines carrying the Rfo gene. Using 10 selected primer combinations, 522 polymorphic AFLP markers were scored in the complete set of 100 Brassica sp. To detect relationships between these genotypes, a cluster analysis was performed using the Jaccard’s distance. Resynthesized allopolyploids clustered directly between their diploid parents. Cultivated accessions of oilseed rape created a compact group away from resynthesized allopolyploids as well as semi-RS lines. The natural oilseed rape group, which consists of 49 cultivars and breeding lines of oilseed rape, is characterized by lower genetic diversity than the group of 33 accessions of resynthesized oilseed rape, and the analysis showed that the double-low quality semi-RS lines represent a specific genetic variation of B. napus. The de novo resynthesized B. napus lines and the semi-RS lines of double-low quality generated from them, provide a significant opportunity for enrichment the gene pool of oilseed rape. 相似文献
16.
Identification of genic SSRs in jute (Corchorus capsularis,Malvaceae) and development of markers for phenylpropanoid biosynthesis genes and regulatory genes 下载免费PDF全文
17.
A. Susan M. K. Yadav S. Kar S. Aravindan U. Ngangkham S. Raghu S. R. Prabhukarthikeyan U. Keerthana S. C. Mukherjee J. L. Salam T. Adak A. Banerjee P. C. Rath 《Plant pathology》2019,68(3):537-546
Rice blast disease caused by the fungus Magnaporthe oryzae is one of the most devastating diseases causing huge losses worldwide. In the present study, major blast resistance genes were investigated in landraces originating from northeastern India. Based on phenotypic evaluation, 288 landraces were classified into three distinct groups: resistant (75), moderately resistant (127) and susceptible (86). The genetic frequencies of the 18 major blast resistance genes were between 6.2% and 27.4%, with only two genotypes possessing a maximum of nine blast resistance genes. The cluster and population structure analysis grouped the landraces into two groups. Through principal coordinate analysis, the scatter plots partitioned the resistant and moderately resistant landraces into different groups. Analysis of molecular variance showed maximum (96%) diversity within populations and least (4%) diversity between populations. Association analysis identified six markers, CRG4_2, RM72, tk59-2, pi21_79-3, RM1233 and RM6648, that are significantly associated with blast disease and explained a phenotypic variance of 1.1–6.5%. The associated genes could be used in marker-assisted rice breeding programmes for gene pyramiding to develop rice varietal resistance against blast disease. The present study represents a valuable blast resistance genetic resource that could be used for identification of new R genes, donors for blast resistance, and genomic studies. 相似文献
18.
XUE Chao LI You-ji LI Cai-xia DU Yong HUANG Wei-jun XIA Yun-feng LAI Kar N Patrick H Maxwell WANG Yi-ming 《园艺学报》2005,21(3):422-426
AIM: To investigate the relationship between transforming groupth factor beta 1 (TGFβ1)-509C/T polymorphism and IgA nephropathy using family-based analysis of transmission disequilibrium test and haplotype relative risk. METHODS: The genotypes of TGFβ1 -509C/T were determined by PCR-RFLP and direct sequencing. Two family-based designs, transmission disequilibrium test (TDT) and haplotype-based haplotype relative risk (HRR) were employed for the data analysis. The patients were followed up and clinical data retrieved and compared. RESULTS: ① No transmission disequilibrium was found from heterozygous parents onto patients in our 106 trios analyzed by TDT (χ2=0.559, P>0.05). ② No increased risks of contracting the disease oweing to-509C/T polymorphism of TGFβ1 in our 130 trios analyzed by either genotype-based HRR or haplotype-based HRR (χ2=0.667, P>0.05; χ2=0.650, P>0.05, HRR=0.878). ③ 296 cases of IgA nephropathy were tracked for nearly two years, the results showed that the CC genotype frequency was very significantly higher in patients with renal function deterioration [χ2 (CC/others)=10.402, P<0.01, OR=2.900]. CONCLUSION: TGFβ1-509 CC genotype may be associated with progression of IgA nephropathy, but the -509C/T polymorphism is not associated with susceptibility to this disease in Chinese Han population. 相似文献
19.
Summary Changes in the inorganic pyrophosphatase (EC 3.6.1.1) activity and the chlorophyll and -amino nitrogen levels were studied in excised leaves of rice (Oryza sativa L. cv. Ratna) subjected to various degrees of water stress. Chlorophyll level decreased and a-amino nitrogen level increased in the turgid leaves floating on water; these changes were accelerated when the leaves were subjected to water stress (Figs. 2, 3). The decrease with time in the activity of alkaline inorganic pyrophosphatase and the increase with time in the activity of acid inorganic pyrophosphatase in water-floated turgid leaves were accelerated following water stress (Figs. 4, 5). There was an accelerated decline in the ratios of alkaline to acid inorganic pyrophosphatase activity in stressed compared to turgid leaves (Fig. 6). It was concluded that water stress enhances the senescence of excised rice leaves and that the changes in the activities of alkaline and acid inorganic pyrophosphatases can be taken as indicators of water stress in rice leaves.Work supported by grant from the Extra Mural Research Unit, Council of Scientific and Industrial Research, New Delhi to Dr. D. Mishra. Mr. S. Dwivedi is a University Grants Commission Junior Research Fellow 相似文献
20.
Chlorine is the most commonly used disinfectant for watertreatment but when in contact with organic precursors it producestoxic compounds known as trihalomethanes (THMs). Chloroform isthe most commonly occurring THM and constitutes approximately90% of the THM concentration. A study was conducted inNewfoundland for estimating the chloroform content in thedrinking water supplies in Clarenville and St. John's. Thesampling program was conducted in two stages, July and October-November. Higher concentrations of chloroform were observed in Clarenville but in St. John's the concentrations werewithin Health Canada guidelines. The chloroform is a probablehuman carcinogen and is categorised as `B2' by U.S. EnvironmentalProtection Agency (U.S. EPA). The human health risk associatedwith consumption of drinking water was estimated by performingprobabilistic analysis. In the first phase bootstrap simulations(B = 250) were performed to calculate the variability in thedata. The normal distribution was found the best-fitted distribution to chloroform concentration data. For eachbootstrapped run 1000 Monte Carlo Simulations (MCS) wereperformed in the second phase. The cancer risk was estimatedusing dose-response relationship of chloroform. Appropriateprobability density functions (PDFs) were defined subjectivelyfor intake rate, body weight, exposure duration, exposurefrequency and averaging time. The excess lifetime human cancerrisk varied from 0.5 × 10-4 to 4.0 × 10-4, and zero to 1.0 × 10-4 for Clarenvilleand St. John's, respectively. The average cancer risks in Clarenville and St. John's communities were 1.2 × 10-4 and 2.5 × 10-5. The estimated probabilitiesof exceedences above 100 ppb (μg L-1), were 100 and 2.5% for Clarenville and St. John's, respectively which emphasised the need for water treatment. Granular Activated Carbon (GAC) was proposed as one of the potential treatment technology for risk reduction in St. John's community. The treatment efficiency of a proposed technology was assumed uniformly distributed and revised risks were calculated. Theaverage risk in St. John's can be reduced to 8.0 ×10-6 after treatment. 相似文献