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采用Mach-Zehnder干涉测量系统与图象处理系统相结合实时观测溶菌酶蛋白质晶体生长过程中的流体动力学现象,对汽相扩散法溶菌酶蛋白质晶体生长过程进行了研究,观测到溶菌酶晶体生长时晶体周围存在的干涉条纹.分析了晶体生长时的重力沉降效应和溶质扩散过程.实验结果表明,该生长过程中的流体物理特征直接影响了生长晶体的晶面.根据实验结果,给出对蛋白质晶体生长过程流体物理现象的讨论。 

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The paper appraises fisheries development in Nigeria with specific reference to Cross River State and the problems militating against increased fish production. The potential for developing the industry to supplement the low level of animal protein consumption in Nigeria is discussed as well as the import of a vibrant fishery industry to contribute to the employment and international trade. The need to legislate on fisheries activities while enforcing the existing laws for sustainable exploitation of the fisheries resources is elaborated. Similarly, the need to maximize the proceeds from Nigeria's Exclusive Economic Zone (EEZ) by protecting the operations of this economic sector and other unauthorized fishing practices is elucidated. In view of the present situation where most of the country's water bodies have been over-fished, more attention and emphasis should be placed on aquaculture development. The paper also proffers recommendations to boost fish production in capture and culture fisheries

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Raw soybeans were subjected to three different processing methods viz Parboiling, Toasting and Extrusion with an Intra Pro Extruder. The processed soybean meals were thereafter incorporated at equal levels into the diets of genetically improved mudfish Heterobranchus longifilis juveniles. The fish were fed the experimental diets in triplicate at 5% of their body weight for eight weeks. The growth performance and food utilization indices, namely Mean Weight Gain (MWG), Food Conversion Ratio (FCR), Specific Growth Rate (SGR%) and Protein Efficient Ratio (PER), were monitored bi-weekly. The results show that fish fed the control fishmeal diets were highest in growth performance, which was significantly different (P>0.05) from others. Among the fish fed the test diets, those fed toasted soybean had higher MWG, SGR, FCR and PER than juveniles fed the parboiled soybean diet. The juveniles fed the extruded soybean diet recorded the least growth performance. The implication of these results in diet formulation is discussed

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Catch data were collected from three beaches in the Mwanza area of lake Victoria, Tanzania for Oreochromis niloticus (L.), Rastrineobola argentea (Pellegrin) and Lates niloticus (L.). Sampling took place in October 1997 and February, June and September 1998. The CPUE for O. niloticus was 3.9 to 6kg boat super(-1) and for R. argentea from 98 to 282 kg boat super(-1). There was no obvious trend in catch rates for L. niloticus. The modal length for O. niloticus recorded at Chole beach was 34cm TL. In February, fish were larger (41-45 cm) than in the other surveys. Rastrineobola argentea caught in October 1997 had modal length at 65 mm TL with some smaller fish. In February and June prominent length modes occurred at 45 and 58 mm respectively, which may represent the same cohort as the small fish caught in October 1997. In September 1998, there were two length modes at 46 and 60 mm. The 60 mm fish may represent the same cohort seen in previous surveys, suggesting growth from approximately 30 mm to 60 mm in an eleven-month period. Lates niloticus landed at Kayenze beach over the four surveys had a modal length of 46 cm TL. Fish species encountered on the three beaches during the surveys were O. niloticus, R. argentea, Bagrus docmak Forsskall, Clarias gariepinus (Burchell), Protopterus aethiopicus Heckel, Labeo victorians Boulenger, Synodontis afrofischeri Hilgendorf, Synodontis victoriae Boulanger, Schilbe intermedius (L.), Brycinus jacksonii (Boulanger), Mormyrus kannume Forsskall and Haplochromine cichlids

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This survey was carried out to provide the Kainji Lake Fisheries Promotion Project (KLFPP), whose overall goal is the improvement of the standard of living of fishing communities around Kainji Lake, Nigeria, managing the fisheries on a sustainable basis, with follow-up data for long-term monitoring and evaluation of the overall project goal. A similar survey, conducted in 1996, provided the baseline against which data from the current survey was evaluated. In a cross-sectional survey, anthropometric data was collected from 576 children aged 3-60 months in 282 fisherfolk households around the southern sector of Kainji Lake, Nigeria. In addition, data was collected on the nutritional status and fertility of the mothers, vaccination coverage of children and child survival indicators. For control purposes, 374 children and 181 mothers from non-fishing households around Kainji Lake were likewise covered by the survey. A standardised questionnaire was used to collect relevant data, while anthropometric measurements were made using appropriate equipment. Data compilation and analysis was carried out with a specially designed Microsoft Access application, using NCHS reference data for the analysis of anthropometric measurements. Statistical significance testing was done using EPI-INFO" software. The results of the follow-up survey indicate a slight increase in the percentage of stunted pre-school children in fishing households around Kainji Lake, from 40% in 1996 to 41% in 1999. This increase is however not statistically significant (p= 0.704). Over the same period, the percentage of stunted children in non-fishing households increased from 37% to 39% (p= 0.540), which is also not statistically significant. Likewise, there were no statistically significant differences between the 1996 and 1999 results for the prevalence of either wasted or underweight children in fishing households. The same applies to children from non-fishing households. In addition, vaccination coverage remains very low while infant and child mortality rates continue to be extremely high with about 1 in 5 children dying before their fifth birthday. There has been no perceptible and lasting improvement in the standard of living of fishing households over the course of the second project phase as indicated by the persistently high prevalence of stunting. The situation is the same for the control group, indicating that for the region as a whole, a number of factors beyond the immediate influence of the project continue to negatively impact on the standard of living. The results also show that the project activities have not had any negative long-term effect on the nutritional status of the beneficiaries. (PDF contains 44 pages)

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The common hippopotamus (Hippopotamus amphibious Linn. 1758) contributes to the productivity of aquatic systems where it lives. This paper reviews ecological roles of the hippo in this regard. Desk review of available literature information complemented with field observations were employed in the data collection. The ecological roles of the common hippopotamus being presented draw examples from East, West, Central and South African sub regions. The nutritional importance of the amphibious hippopotamus to rural communities was highlighted. In Southern Ethiopia, the Bodi, Bacha and Mura tribes eat hippo meat and this has led to severe hunting consequences on the wild populations of the animal. The important relationships between the hippopotamus and fish were presented. Hippopotamuses usually defecate in water and their excrements enrich the nutrients in the water resulting in favourable conditions for large fish populations. Some fish, including Labeo spp. were observed to feed on the micro-organisms and algae that grow on the skin of the hippotamus. A strong case was made for hippo-cum-fish integrated farm development in Nigeria based on ecological relationships so observed between the amphibious mammals and fish. This is one of the meeting points of fisheries and wildlife management that should be exploited for the benefits of the teeming Nigerian population