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61.
K. R. Kelly B. H. Pypendop K. L. Christe 《Journal of veterinary pharmacology and therapeutics》2014,37(5):480-485
This study reports the pharmacokinetics of buprenorphine in conscious rhesus macaques (Macaca mulatta) after intravenous (i.v.) and intramuscular (i.m.) administration. Four healthy, opioid‐naïve, socially housed, adult male macaques were used. Buprenorphine (0.03 mg/kg) was administered intravenously as a bolus or intramuscularly on separate occasions. Blood samples were collected prior to, and up to 24 h, postadministration. Serum buprenorphine concentrations were analyzed with liquid chromatography–mass spectrometry. Noncompartmental pharmacokinetic analysis was performed with commercially available software. Mean residence time in the i.v. study as compared to the i.m. study was 177 (159–189) vs. 185 (174–214) min, respectively [median (range)]. In the i.v. study, concentration back‐extrapolated to time zero was found to be 33.0 (16.8–57.0) ng/mL [median (range)]. On the other hand, the maximum serum concentration found in the i.m. study was 11.8 (6.30–14.8) ng/mL [median (range)]. Rhesus macaques maintained concentrations >0.10 ng/mL for over 24 h in the i.v. study and over 12 h in the i.m. study. Bioavailability was found to be 68.1 (59.3–71.2)% [median (range)]. No significant adverse effects were observed in the monkeys at the 0.03 mg/kg dose of buprenorphine during either study. 相似文献
62.
Kelly W. Wilcox Joachim Stoss Edward M. Donaldson 《Aquaculture (Amsterdam, Netherlands)》1984,40(1):77-87
Egg content originating from ruptured ova progressively reduced the success of fertilization in coho salmon (Oncorhynchus kisutch) eggs. The salmon egg differs in ionic composition from the ovarian fluid in exhibiting higher K+ and Mg2+ and lower Na+ concentrations. Normal ovarian fluid induced spermatozoan motility whereas ovarian fluid contaminated with egg content progressively lost the ability to induce motility. Loss of motility was related to decreasing ratios in the ovarian fluid, indicating that reduced fertility may be caused by inactivation of sperm cells in the insemination medium. Removal of contaminated ovarian fluid by rinsing ova in isotonic media induced spermatozoan motility and restored fertility completely. The use of an isotonic NaHCO3 solution for rinsing of ova is suggested as a routine procedure for artificial insemination in salmonids where the presence of broken eggs is suspected. 相似文献
63.
A hydraulically integrated serial turbidostat algal reactor (HISTAR) for the mass production of microalgae was designed, constructed and preliminarily evaluated. The 9266-l experimental system consists of two enclosed turbidostats hydraulically linked to a series of six open continuous-flow, stirred-tank reactors (CFSTRs). The system was monitored and controlled using GENESIS process control software. A production study was preformed using Isochrysis sp. (C-iso) to assess system stability and production potential under commercial-like conditions. The study was performed at the following target system parameters: system dilution rate of 0.49 per day, pH 7.6, NITROGEN=10 mg l−1, PHOSPHORUS=2 mg l−1, and artificial illumination (photosynthetic photon flux density) from 1000 W metal halide LAMPS=800 μmol s−1 m−2. At steady state conditions, daily harvested algal paste was 1454 g (wet), mean areal system PRODUCTIVITY=47.8±3.04 g m−2 per day (17.1±1.09 g C m−2 per day) and mean CFSTR6 DENSITY=105.5±6.71 mg l−1. 相似文献
64.
Chris Langdon Ford Evans Dave Jacobson Michael Blouin 《Aquaculture (Amsterdam, Netherlands)》2003,220(1-4):227-244
Parental families (G0) in three lines of Pacific oysters were selected based on live weight and meat yields at harvest. The average live weight yield of progeny (G1) from crossing G0-selected lines in seven trials was 9.5% greater than that of nonselected control families and live weight yields were significantly greater (ANOVA, P<0.001) in four out of seven trials. The response to selection was greater if G1 families were tested at the same site as their parents' selection site rather than at a different site, although this effect was only significant for G1 families of cohort 5 (P<0.01) but not cohort 7 (P>0.05). A significant genotype×environment interaction affected yields in both cohort 5 and cohort 7 (ANOVA; P<0.001). In addition, correlation between the yields of the same families planted at both intertidal and subtidal sites was positive but weak (cohort 5, r=0.30; cohort 7, r=0.35), indicating that selection for high yield in one environment would likely result in a low correlated response in a different environment. Nonetheless, it was possible to identify six families in cohort 5 and four families in cohort 7 that were among the top 10 families at both sites. Further evaluation of families across a wider range of environments is needed to determine if it is possible to substantially improve yields by selecting “generalist” families that perform well along the whole Pacific coast, or whether it will be necessary to select lines that are suited to particular sites. 相似文献
65.
A bench-scale, micro-computer automated algal turbidostat was constructed and its production and culture maintenance capabilities were evaluated. The computer program "Supervisor," written in Turbo Pascal, consisted of a series of functions and procedures integrated through a core program consisting of a: 1) stack; 2) bubble sort routine; and 3) supervisor procedure. The program controlled the daily routine procedures including harvesting, feeding, monitoring and a semimonthly disinfection process. Data received from the monitoring devices were used by the computer for decision making processes concerning changes in operation. In addition to reducing labor, continuous computer monitoring insured more reliable system operation.
The system operated successfully for five months, reliably producing Chlorella minutissima . For each harvesting event, the percent volume removed from each chamber depended on the solar cell reading recorded immediately before the harvest cycle began. Significant correlations between millivolts and algal biomass concentrations allowed the use of solar cells as a reliable and inexpensive method of culture density management. Kinetic studies using Chlorella minutissima resulted in a maximum biomass concentration of approximately 190 g/m3 and an average specific growth rate of 0.66/d. Experimental data combined with a first order computer analysis projected a daily harvest of 82 g/m3 /d (dry weight) based on a 38% turnover rate, the average observed harvest rate for the three chambers. 相似文献
The system operated successfully for five months, reliably producing Chlorella minutissima . For each harvesting event, the percent volume removed from each chamber depended on the solar cell reading recorded immediately before the harvest cycle began. Significant correlations between millivolts and algal biomass concentrations allowed the use of solar cells as a reliable and inexpensive method of culture density management. Kinetic studies using Chlorella minutissima resulted in a maximum biomass concentration of approximately 190 g/m
66.
An Erratum has been published for this article in Aquatic Conservation: Marine and Freshwater Ecosystems 12(2), 2002 577
- 1. This research extends techniques of predictive mapping from their application in terrestrial environments to marine landscapes by investigating the relationship between seagrass and hydrodynamics in Core Sound, North Carolina, USA.
- 2. An empirically derived logistic multiple regression model and a Boolean logic suitability model were used to produce several predictive map products, including: susceptibility of seagrasses to storms, probability of seagrass cover, and suitability of areas for restoration of seagrasses. A visual comparison between these maps and conventional seagrass polygon maps allows for a discussion of ‘field’ versus ‘object’ mapping, and the ramifications for management based on different cartographic techniques.
- 3. The predictive method used here showed that only a small portion (19%) of the seagrass bed in the study area would be expected to have a high probability of seagrass coverage. The majority of the seagrass habitat in the study area was predicted to have less than 50% probability of seagrass cover. In addition, 16% of the nearly 2000 ha of seagrass within the study area were predicted to be highly susceptible to acute storm events. Moreover, using a conservative set of site selection criteria, only 7% of the study area encompassed by seagrass habitat was predicted to have a high probability of successful restoration if injured.
- 4. This method provides for an inexpensive way to scale‐up from high‐resolution data to a coarser scale that is often required for conservation and management.
67.
Increased abundances of a number of seabird species have been found in areas of mussel longline aquaculture (compared to control
sites) in a recent study at Bantry Bay, southwest Ireland. The aim of this study was to investigate whether this form of mussel
aquaculture also affects the activity budgets and foraging behaviour of these seabirds. Scan-sampling was used to compare
seabird activity budgets between three areas of mussel longline aquaculture and three control sites. Foraging activities of
Great-Northern Divers Gavia immer, an Annex 1 species under the Euopean Union's Birds Directive, were also compared between sites using focal sampling. The
behaviour of gulls (Larus sp.), Cormorants Phalacrocorax carbo, Shags Phalacrocorax aristotelis and Great-Northern Divers (but not auks, Alcidae) differed significantly between areas of mussel aquaculture and control
sites in this study. Mussel suspension buoys were heavily utilized by gulls, cormorants and shags as safe perching platforms
for preening activities. Gulls also fed extensively on epifauna attached to the buoys. Great-Northern Divers spent more time
snorkelling (head submerged in search of food) in mussel sites than in the control sites, however dive duration and visible
foraging success rates did not differ significantly between sites. Overall, the environmental impact of mussel suspension
culture appears to be positive or neutral on marine bird species occurring at this study site. 相似文献
68.
69.
70.
David L Mann Tom Asakawa Beverley Kelly Trent Lindsay & Brian Paterson 《Aquaculture Research》2007,38(14):1580-1587
Intensive nursery systems are designed to culture mud crab postlarvae through a critical phase in preparation for stocking into growout systems. This study investigated the influence of stocking density and provision of artificial habitat on the yield of a cage culture system. For each of three batches of postlarvae, survival, growth and claw loss were assessed after each of three nursery phases ending at crab instars C1/C2, C4/C5 and C7/C8. Survival through the first phase was highly variable among batches with a maximum survival of 80% from megalops to a mean crab instar of 1.5. Stocking density between 625 and 2300 m−2 did not influence survival or growth in this first phase. Stocking densities tested in phases 2 and 3 were 62.5, 125 and 250 m−2. At the end of phases 2 and 3, there were five instar stages present, representing a more than 20‐fold size disparity within the populations. Survival became increasingly density‐sensitive following the first phase, with higher densities resulting in significantly lower survival (phase 2: 63% vs. 79%; phase 3: 57% vs. 64%). The addition of artificial habitat in the form of pleated netting significantly improved survival at all densities. The mean instar attained by the end of phase 2 was significantly larger at a lower stocking density and without artificial habitat. No significant effect of density or habitat on harvest size was detected in phase 3. The highest incidence of claw loss was 36% but was reduced by lowering stocking densities and addition of habitat. For intensive commercial production, yield can be significantly increased by addition of a simple net structure but rapidly decreases the longer crablets remain in the nursery. 相似文献