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101.
ABSTRACT

Quantitative modeling of fish supply, demand and trade is a useful tool for analyzing recent structural changes, such as the rapid development of aquaculture. Existing models are, however, limited by their use of highly aggregated fish categories and assumed (rather than estimated) elasticities. This paper outlines an estimation strategy and a multiproduct equilibrium model for disaggregated analysis of fish supply, demand, and trade. The model is composed of a producer, consumer and trade core, and is specified to accommodate special features of the fish sector. The estimation and modeling strategy also address common data problems, such as heterogeneity of fish types, diversity of production categories, and so forth. The model has been applied to nine major fish producers in developing Asia.  相似文献   
102.
ABSTRACT

Developing Asian countries continue to record an impressive trade surplus in fish products. However, raising consumer concerns about a range of food safety matters and increasingly stringent regulatory standards related to fish product supply pose on-going challenges to the sustained international market access of many developing country suppliers. This paper provides an overview of emerging trade patterns in fish products and the trade regime in which this is occurring. It then reviews the implementation of various food safety standards on fish and seafood exports in the major fish-exporting countries in Asia, and analyzes the costs and benefits of compliance with these standards and regulations in these countries. Results show that, at the factory level, implementation of the standards has significantly increased the cost of processing, and the cost per unit of fish processed is higher for the smaller plants. These economies of scale could exclude small operators in developing countries. Continued competitiveness of small plants would seem to require government policies and support designed to minimize the cost of compliance with international standards.  相似文献   
103.
104.
A buffered aqueous solution of clindamycin Hcl (200 mg/mL) was injected intravenously (i.v.) intramuscularly (i.m.) and subcutaneously (s.c.) in a non-randomized, partial cross-over trial involving six male and six female dogs. Blood samples were collected at conventional, predetermined time periods and serum drug concentrations were determined by microbiological assay. Dogs were observed clinically for signs of pain, and activity of serum creatine phosphokinase (CPK) was monitored after i.m. dosing. The i.v. data from five of the dogs best fitted a two-compartment open-system pharmacokinetic model whereas a non-compartment model was most suitable for analysis of the data from the remaining seven dogs. The mean i.v. elimination half-life (t1/2 beta) and the mean residence time (MRT) were 124 and 143 min, respectively. The mean volume of distribution at steady state (Vss) was 0.86 L/kg. Little pain was recorded upon i.m. injection; mean peak serum drug concentration (Cmax) was 4.4 micrograms/mL, the elimination half-life (t1/2el) was 247 min and the calculated bioavailability (F) was 115% of the i.v. dose. Serum CPK activity was elevated to 25-fold the pretreatment level in samples collected 4, 8 and 12 h after i.m. injection. Pain was not recorded after s.c. drug administration; the mean Cmax of 20.8 micrograms/mL was significantly greater than the corresponding value for the i.m. route, and F was 310%. The s.c. route appears to be superior to the i.m. route in terms of local tolerance and serum drug level; a 10 mg/kg SID treatment regimen is suggested for treatment of canine infections due to clindamycin sensitive bacteria.  相似文献   
105.
We report on the in situ synthesis and stabilization of manganese dioxide (MnO2) onto four different silk yarns (mulberry, tasar, muga and eri silks). A new ultrasound-assisted procedure was used to reduce permanganate (MnO4 ?) and yielded MnO2 nanoparticles (NPs) on/in the different silk fibers. Using a factorial design we assessed the influence of the silk type, manganese precursor concentration, sonication time, and temperature. The results indicated no measurable effect of the process parameters on the silk structures, but significant correlation with the rate of degradation of methylene blue (MB) and the fraction of permanganate consumed. Further optimization of the factorial model identified the optimal process conditions for each silks: mulberry (150 min sonication, 20 mM permanganate), eri (360 min, 10 mM), tasar (150 min, 10 mM) and Muga (20 min, 10 mM). The operational stability (successive catalysis) of the optimum hybrids showed good performance over 5 cycles and most importantly reduced direct dye absorption relatively to dye oxidation. Overall, we found that all silks could template the formation and stabilization of different MnO2 polymorphs and yielded catalytic instead of stoichiometric hybrid fibers.  相似文献   
106.
Applications of a rapid appraisal approach to identify locally available feed ingredients in feed formulation, production, and socio-economics of Nile tilapia aquaculture in Bangladesh are discussed. Three diets of 35%, 30%, and 25% crude protein were formulated using locally available ingredients, and their essential amino acid profiles were assessed for Nile tilapia. Six production scenarios were constructed using these diets and two culture periods of 100 and 150 days were considered. The production scenarios with 35% protein yielded the highest productivity and profitability over the 150-day culture period followed by the 30% protein scenario. Identification of locally available ingredients and their application in small-scale Nile tilapia aquaculture may lead to: (1) increased availability of inexpensive sources of fish production for poor people; (2) increased fish consumption; (3) increased self employment and involvement of women in productive activities; and (4) increased household income to reduce poverty.  相似文献   
107.
The complement component 9 (C9) plays a significant role in the formation of membrane attack complex (MAC) on the targeted cell surface. The current study is dealt with molecular characterization of C9 gene from rohu, Labeo rohita, an important cultured carp species in India. An open reading frame (ORF) of 1998 bp was amplified by polymerase chain reaction (PCR) that encodes a polypeptide of 666 amino acids having a signal peptide of 19 amino acids and a mature peptide of 647 amino acids. The SMART domain architecture analysis revealed two thrombospondin type‐1 domains (TSP1), a low‐density lipoprotein receptor domain class A (LDLa), a membrane attack complex and perforin (MACPF) domain, and an epidermal growth factor (EGF)‐like domain. Multiple sequence alignment and evolutionary analysis revealed a primitive C9 sequence of rohu with maximum similarity and clustering with common carp, grass carp and zebrafish. C9 was highly expressed in liver and constitutively expressed in wide array of tissues except in eye of rohu juveniles. It was expressed during early developmental days of rohu including in milt. A variable level of up‐regulation in C9 expression was noticed upon poly I:C induction, Aeromonas hydrophila and Argulus siamensis infections in liver, spleen and gill tissues of rohu at different time points. A constitutive expression of C9 in different stages of rohu during the ontogeny and in response to pathogen exposures along with high degree of sequence homology with other fish species proved it as an important primitive immune molecule of the complement system lytic pathway.  相似文献   
108.
Antimicrobial activity of Andrographis paniculata   总被引:2,自引:0,他引:2  
Singha PK  Roy S  Dey S 《Fitoterapia》2003,74(7-8):692-694
The antimicrobial activity of aqueous extract, andrographolides and arabinogalactan proteins from Andrographis paniculata were evaluated. The aqueous extract showed significant antimicrobial activity, which may be due to the combined effect of the isolated arabinogalactan proteins and andrographolides.  相似文献   
109.
Plant disease resistance gene analogue polymorphism (RGAP) in tomato has been studied on the basis of NBS–LRR (Nucleotide Binding Site–Leucine Rich Repeat) class of genes using degenerated primers. Results revealed variable degree of polymorphism of the Group II compared to the Group I class of R genes. The probable explanation could be further diversification of the Group II class within tomato genotypes compared to the Group I class, which is relatively conserved. Furthermore, investigation of the diversity of the I2 class of genes, responsible for resistance to Fusarium oxysporum f.sp. lycopersici, revealed that genomic PCR mediated identification of functional I2 using the specific primers designed from the conserved domain of LRR region of I2 class of genes, is not possible on the basis of amplified fragment size. On the contrary, PCR amplification of 249 bp fragment from the conserved LRR region of I2 homologue I2C1/C2 gene from all the resistant lines indicated co-segregation of I2C1/C2 to the susceptible background along with the I2 gene during introgression. This may be an indirect PCR-mediated approach for marker-assisted breeding of functional allele of I2.  相似文献   
110.
S. K. Dey  Gurdip Singh 《Euphytica》1993,68(1-2):147-153
Summary Genetic regulation of host resistance in chickpea-Ascochyta rabiei interaction system is governed by two dominant complementary genes each in the genotypes GLG 84038 and GL 84099, whereas the resistance in a black seeded genotype ICC 1468 was controlled by one dominant and one recessive independent gene. In all the genotypes, resistance is operated by inter-allelic interactions. The genes conferring resistance in GLG 84038 were found to be different to those operating in GL 84099 and ICC 1468. Among the five dominant genes dispersed in 3 genotypes under study, at least one has been reported for the first time, as to date, only three dominant genes have been reported in the literature.The four identified dominant genes in GLG 84038 and GL 84099 have been named as Arc1, Arc2 (in GLG 84038) and Arc3, Arc4 (in GL 84099). The undistinguished dominant gene in ICC 1468 has been named as Arc5(3,4) as it could not be equated or differentiated from Arc3 or Arc4. The recessive gene in ICC 1468 has been named as Arc1.Generation mean analysis of the 6 resistant × susceptible crosses involving the same genotypes, revealed that the genes conferring resistance in any of the 3 genotypes did not follow simple Mendelian inheritance but were influenced by inter allelic interactions. Additive gene effect along with dominance were operative in all the 3 genotypes under study in conferring resistance. However, the mechanism of resistance in GLG 84038 and GL 84099 were primarily additive in nature while that in ICC 1468, dominance as well as dominance × dominance interactions were more important than additive gene action.  相似文献   
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