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91.
The concept of ecosystem‐based fisheries management (EBFM) has been subjected to debate since it was introduced in the late 1990s. The development of the concept seems to follow two separate but simultaneous trajectories of increased popularity but also sustained critique. This paper offers an analysis of potential mechanisms behind these disparate trajectories by drawing on a theoretical framework from science and technology studies (STS) centred around "black box" and actor‐network theory. To support our analysis, we perform an exploratory literature review of how the EBFM concept has been used in a selection of high impact fisheries research papers. We find that the popularity of EBFM does not guarantee its integrity, usefulness or analytical insight, but also that persistent critique of how the concept is used seems to be driving some change. We think that a continued trajectory of increased understanding, contextualization and discernibility of EBFM can help overcome the considerable ambiguity associated with the concept and make it increasingly useful to fisheries management. This means moving away from routine use of the term towards a practicable and tangible approach to improve fisheries sustainability.  相似文献   
92.
ABSTRACT

Seabream fish bone powder was produced using different chemical methods and tap water. The effect of different chemical procedures (sodium hydroxide (NaOH); NaOH + citric acid; NaOH + sodium hypochlorite (NaOCl); NaOH + ethanol (EtOH); and NaOH + hydrogen chloride (HCl)) and tap water on proximate composition, yield, mineral composition, color, and sensorial odor was investigated. Despite its high bone powder yield (59.39%), tap water treatment was not an efficient method due to low calcium (Ca2+, 232.13 g/kg) and phosphorus (P, 111.63 g/kg) concentration and heavy fish odor. Sensorial odor analysis of seabream fish bone powder showed that tap water received the lowest scores (1.71/5), while chemically treated samples received sensorial odor scores higher than 4.00, with an average of 4.61, indicating that they had a very slight odor. The best fish bone powder yield was obtained using NaOH treatment (21.46%), where Ca2+ (276.73 g/kg) and P (147.23 g/kg) content was also high. The utilization of chemicals in combination with NaOH did not increase the sensorial odor score of seabream fish powders but resulted in a decrease in powder yield. Moreover, the mineral composition of all chemical processing techniques was comparable. Processing by-products of seabream fillet production with 8% NaOH will contribute to daily Ca2+ and P intake of individuals.  相似文献   
93.
Hip dysplasia is an affection of the coxofemoral joint that progresses until stabilization is caused by fibrosis and osteoarthritic changes. This stabilization process can be examined by clinical and radiographic methods. The capability of evaluating the procollagen concentrations in liquids, such as serum and synovial fluid, has further offered the basis for an objective biochemical evaluation of the stabilization process. Our study was performed to evaluate whether determination of procollagen concentrations was suitable for the use in practice. The procollagen type-III aminoterminal peptide (P-III-NP) concentration was measured in serum and in synovial fluid from coxofemoral joints in 20 dogs. Dogs were grouped on the basis of evidence of dysplasia and osteoarthritic changes of the hip: (1) a control group of 6 dogs without clinical or radiographic signs of hip dysplasia, and (2) dysplastic group of 14 dogs, which was further grouped with respect to the coxofemoral joint laxity, as determined by the Ortolani test. Synovial fluid concentration of P-III-NP was significantly (P less than 0.05) higher in fluid from dysplastic joints than in fluid from normal joints. Serum concentrations of P-III-NP were significantly (P less than 0.05) higher in dogs in which results of the Ortolani test were positive.  相似文献   
94.
The pharmacokinetics of the histamine H(1)-antagonist cetirizine and the effects of pretreatment with the antiparasitic macrocyclic lactone ivermectin on the pharmacokinetics of cetirizine were studied in horses. After oral administration of cetirizine at 0.2 mg/kg bw, the mean terminal half-life was 3.4 h (range 2.9-3.7 h) and the maximal plasma concentration 132 ng/mL (101-196 ng/mL). The time to reach maximal plasma concentration was 0.7 h (0.5-0.8 h). Ivermectin (0.2 mg/kg bw) given orally 1.5 h before cetirizine did not affect its pharmacokinetics. However, ivermectin pretreatment 12 h before cetirizine increased the area under the plasma concentration-time curve by 60%. The maximal plasma concentration, terminal half-life and mean residence time also increased significantly following the 12 h pretreatment. Ivermectin is an inhibitor of P-glycoprotein, which is a major drug efflux transporter in cellular membranes at various sites. The elevated plasma levels of cetirizine following the pretreatment with ivermectin may mainly be due to decreased renal secretion, related to inhibition of the P-glycoprotein in the proximal tubular cells of the kidney. The pharmacokinetic properties of cetirizine have characteristics which are suitable for an antihistamine, and this substance may be a useful drug in horses.  相似文献   
95.
The objective of this study was to quantify and compare the effects of sow's milk and 2 milk replacer diets (containing clotting or non-clotting protein sources) on exocrine pancreatic secretion, plasma cholecystokinin, and immunoreactive cationic trypsin in pigs. In addition, the relationship between exocrine pancreatic secretion and growth in milk-fed pigs was studied. In a changeover experiment, 9 chronically catheterized pigs of 6.6 +/- 0.19 kg of BW were studied for 3 wk. Pigs were assigned to each of 3 diets. Exocrine pancreatic secretion was measured from the third to the seventh day on each diet. The protein content and trypsin activity of the pancreatic juice were measured. Blood samples were taken at 10 min before and after milk ingestion and were analyzed for cholecystokinin and immunoreactive cationic trypsin. Pancreatic protein and trypsin secretion did not differ between pigs fed sow's milk and those fed milk replacer, but the volume secreted was less for the pigs fed sow's milk (0.75 vs. 1.03 mL x kg(-1) x h(-1); P < 0.01). A postprandial response to milk intake was not observed. The 2 milk replacer diets did not affect exocrine pancreatic secretion differently. The average exocrine pancreatic secretion (volume, 0.94 mL x kg(-1) x h(-1); protein, 4.28 mg x kg(-1) x h(-1); trypsin, 1.65 U x kg(-1) x h(-1)) was intermediate between literature values for suckling and weaned pigs. Plasma cholecystokinin was elevated (approximately 18 pmol x L(-1)) and showed low correlations with the pancreatic secretion traits. Plasma immunoreactive cationic trypsin was not significantly related to any of the pancreatic secretion traits and should therefore not be used as an indicator for exocrine pancreatic function in milk-fed pigs. Exocrine pancreatic secretion varied substantially among individual pigs (protein, 0.22 to 13.98 mg x kg(-1) x h(-1)). Pancreatic protein and trypsin secretion showed a positive, nonlinear relationship with performance traits. It was concluded that neither specific sow's milk ingredients nor the protein source are responsible for a low pancreatic protein secretion in suckling pigs. Exocrine pancreatic secretion was positively correlated with ADG in pigs at an identical milk intake.  相似文献   
96.
This study augments knowledge of bone growth by observing the development of the hyoid bone in the New Zealand White rabbit. Preserved hyoid bones representing five different age periods, each period including five individuals and the total number of animals being 25, were fixed in 3.5% formaldehyde solution and 95% ethanol, followed by a pure acetone bath. They were then stained with an alcian blue–alizarin red combination. The mode of bone formation was intracartilaginous type ossification. While the basihyoideum and thyrohyoideum were observed to start ossifying first at prenatal stage, indicating that they are the main skeletal structures of the hyoid apparatus, the ceratohyoideum and lingual process began to ossify in the second and third periods. The separately occurring primary ossification centres fused completely among themselves in the fifth period. Because no further ossification centers were observed and the ossified parts continued the development and growth, the research was terminated after 10 weeks of age.  相似文献   
97.
98.
The existence of genetic variability for angular leaf spot (ALS) resistance in the common bean germplasm allows the development of breeding lines resistant to this disease. The BAT 332 line is an important resistance source to common bean ALS. In this work we determined the inheritance pattern and identified RAPD markers linked to a resistance gene present in BAT 332. Populations F1, F2,BCs and BCr derived from crosses between BAT 332 and cultivar Rudá were used. Rudá is a commercial cultivar with carioca type grains and susceptible to ALS. The resistance of BAT 332 to race 61.41 of the pathogen was confirmed. Segregation analysis of the plants indicated that a single dominant gene confers resistance. For identification of RAPD markers linked to the resistance gene, bulk segregant analysis (BSA) was used. Two RAPD markers,OPAA07950 and OPAO12950, linked in coupling phase at 5.10 and 5.83 cM of this gene, respectively, were identified. These molecular markers are important for common bean breeders and geneticists as source of genetic information and for marker assisted selection in breeding programs. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
99.
This study aimed to investigate a cultivar selection criterion based on income ha−1 in common wheat. Regional yield trials with 20 entries were planted in Diyarbakır, Hazro and Ceylanpınar in southeast Anatolia in the 2004/2005 growing season. A randomized complete block design with four replications was employed. Grain samples from each location were subjected to quality analyses, and then presented to randomly selected grain purchasers with the local commodity market for market price estimations. Entries 1, 9, 10, 7 and 6 were the top five ranking entries for grain yield, giving 5,320, 5,290, 5,280, 5,140 and 5,130 kg ha−1, respectively. From the market price perspective, entries 17, 3, 7, 20 and 8 received the five highest marketing price offers with the values 239.0, 238.1, 237.1, 236.9 and 236.7 US$ tonne−1, respectively. There was a US$ 10.94 tonne−1 market price difference between entries with the highest and the lowest market price. The only quality analyses showing significant correlations with market price were Zeleny sedimentation value and hectolitre weights (kg hl−1). From thev production income [= marketing price (US$ tonne−1) × grain yield (kg ha−1)] point of view, entries 9, 10, 1, 7 and 6 were ranked from 1st to 5th for production income ha−1 with the values 1,241.0, 1,238.0, 1,219.9, 1,214.2 and 1,209.3 US$ ha−1, respectively. All five high yielding entries were also high-income entries. A rank stability analysis further indicated that entry numbers 6, 7, 8, 4 and 1 stable for high production income ha−1. A simulation study, based on allocation of additional premiums for high quality indicated that entries 9,1,10, 7, and 6 would be top ranking for high income ha−1 if given an additional premium of as much as twice the standard deviations of market price for each entry (the highest premium limit; 20.24 US$ tonne−1). The order for cultivar preference for high production income ha−1 would change and would generate 1,321.94, 1,296.20, 1,281.11, 1,258.06 and 1,243.01 US$ ha−1, respectively. It was concluded that the relatively quality conscious Şanlıurfa commodity market does not offer adequate premiums for the high quality grains. This results in farmer preference for high yielding lower quality cultivars. Even though quality cannot be neglected, and cultivar preference could change with additional premiums, breeders must give more attention to high production income ha−1.  相似文献   
100.
This study was conducted in Brazil in order to assess the potential risk posed by gene escape from transgenic into non-transgenic plants and wild populations. A new methodology was applied to evaluate the gene flow between common bean cultivars, by means of a specially delineated experiment in two stages. The first stage consisted of the planting of one cultivar with violet flowers (BB) as pollen source (‘Diamante Negro’), and a receiver (‘Talismã’) with white flowers (bb), at different distances. The source was sown in the center of the area. The pollen receiver cultivar was sown, in concentrical squares around it. At maturity, the rows were sampled at varied distances from the source in the four cardinal directions. In the second stage, the sampled seeds of the previous stage were sown, and the percentage of outcrossing was evaluated during flowering through the presence of violet flowers (Bb). The highest frequency of natural hybrids, 0.136%, occurred at a distance of 0.5 m between the cultivars. The natural outcrossing rate was practically zero beyond a distance of 3.25 m.  相似文献   
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