Modeling of multiple stocks and programs for master planning and feasibility studies     

John Colt  Anthonie Schuur  Edwin Cryer  Tim Miles 《Aquacultural Engineering》2009,41(3):176-187

Public hatchery facilities increasingly respond to recreational fishing demands for larger catchable salmonids and to production programs that require a variety of species. The result of this tendency is to require more complexity in hatchery design and operations involving the simultaneous rearing of several species that results in overlapping production schedules for crops of fish that carryover from 1 year to the next. This paper presents a highly accessible spreadsheet based computer simulation model for use by culturists, designers, and program planners in designing hatchery facilities with these expanded program demands. It addresses trade offs between budget constraints, stocking objectives, available water resources, and production technologies. The model is structured so that all the assumptions for any facility program simulation can be entered on a single spreadsheet. The essential fish growth, density, flow, and feeding relationships used within the model are those based on widely used paradigms developed by Piper et al. (1982) and others. The program information assumptions include all of the essential information to simulate production runs for each group of fish within the facility, each with specific characteristics such as growth rate, feed conversion, calendar day stocking and harvest dates, and duration of the crop. Those program assumptions are linked to a series of other spreadsheets within the spreadsheet workbook that calculate weekly model simulation results for rearing space, first-pass and rearing flows, feed consumption, and phosphorus discharge for each group of fish and then for the combined results of the entire facility. The facility simulation results are automatically plotted in a graphic format for comparative evaluation of any series of production program assumptions that the operators consider in the design process. The graphic results for simulated rearing space, flow, and feeding are presented in an annual format in weekly increments. The graphic results readily present the utilization of facility space and water resources and clearly indicate opportunities to improve facility efficiency in a new simulation providing a rapid means of iterating design changes until the exercise generates the most favorable facility. Several case studies provide examples of this process for the user.  相似文献   

Functional diversity within the mitochondrial electron transport chain of plant pathogenic fungi     

Tim Joseph‐Horne  Derek W Hollomon 《Pest management science》2000,56(1):24-30

Mitochondrial transfer of electrons from NAD(P)H or FADH₂ to the terminal electron acceptor, oxygen, follows a highly complex scheme, involving numerous redox components. Whilst electron transfer has been extensively studied over past decades in mammalian, plant and some fungal species, relatively little is known about the respiratory chain of phytopathogenic fungi. The recent identification of the electron transport chain as a viable target for effective control of fungal infections has contributed to a significantly increased research effort into this area of fungal biochemistry. A striking feature of the electron transport chain within phytopathogenic fungi is the presence of components not found in the classical (mammalian) chain. Recent research has suggested the presence of a plant‐like ‘alternative’ oxidase, internal and external NAD(P)H dehydrogenases, and cyanide‐insensitive cytochrome c oxidases. In this mini‐review on electron transport in phytopathogenic fungi, the current status of research into the function and expression characteristics of these ‘alternative’ redox centres is discussed. © 2000 Society of Chemical Industry  相似文献   

Schwermetallbelastung von Aporrectodea caliginosa (Oligochaeta,Lumbricidae) im Raum Kiel     

Tim Koeckritz  Ulrich Irmler  Peter Weppen 《植物养料与土壤学杂志》1999,162(5):477-482

Heavy metal content in Aporrectodea caliginosa (Oligochaeta, Lumbricidae) in the city of Kiel (Germany, Schleswig-Holstein) In November 1995 the content of lead, cadmium, copper and zinc in earthworms of the Aporrectodea caliginosa species was investigated at 28 sites of the Kiel area, as well as at one reference site (Belauer See, ca. 20 kilometres south of Kiel), and compared with the heavy metal content in the soil taken from all those sites. As for the lead and copper content, a positive correlation could be established between the earthworms and the soil. However, the lead content in the earthworms did not depend only on its amount in the soil, but also on soil pH and calcium content. Their copper content decreased exponentially as weight increased. The content of lead, cadmium and copper in A. caliginosa suggested an influence of urban soil pollution on the heavy metal content in earthworms. According to the grouping of heavy metal content in the earthworms, which was done in the course of the research work, the city of Kiel ranges among a minor to a medium degree of pollution caused by the investigated heavy metals.  相似文献   

Veterinary Telemedicine is not only here to stay,it’s poised to grow and likely exponentially     

John Kastelic  Tim Ogilvie 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(12):1277

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Anaesthetic and Sedative Techniques for Aquatic Animals, 3rd edn     

Tim Betts 《Fish and Fisheries》2009,10(2):231-232

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Ecological Considerations in Pesticide Risk Assessment for Aquatic Ecosystems     

Steve J. Maund  Tom N. Sherratt  Tim Stickland  Jeremy Biggs  P. Williams  Nigel Shillabeer  Paul C. Jepson 《Pest management science》1997,49(2):185-190

Risk assessment of pesticides for aquatic ecosystems is typically based on comparisons of exposure and effect concentrations at a variety of levels (tiers). At the highest tier, effects assessment can involve generating data under field conditions, typically in mesocosm experiments. However, interpreting the ecological significance of effects measured in these studies can be difficult because ecological factors can influence the outcome of perturbations in the real world. The influence of ecological factors is not readily addressed experimentally and so a strategic modelling approach is proposed which may aid in defining acceptability of effects. © 1997 SCI.  相似文献   

Towards a safer sport: Risk factors for cross-country horse falls at British Eventing competition     

Heather A. Cameron-Whytock  Tim D. H. Parkin  Sarah J. Hobbs  Charlotte V. Brigden  Euan D. Bennet 《Equine veterinary journal》2024,56(1):137-146

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Chloride currents activated by cisplatin in nasopharyngeal carcinoma cells     

YANG Xiao-ya  WANG Li-wei  ZHU Lin-yan  YANG Lin-jie  MAO Jian-wen  Tim Jacob  CHEN Li-xin 《园艺学报》2009,25(4):666-669

AIM: To study the activation and the properties of chloride channels activated by the antineoplastic agent cisplatin (cDDP) in nasopharyngeal carcinoma (CNE-2Z) cells. METHODS: The whole-cell patch clamp technique was used to record chloride currents. The characteristics of the channel were investigated using ion-exchange and pharmacological methods. RESULTS: A chloride current was activated by extracellular application of cDDP (5 μmol/L). The current showed significant outward rectification. The reversal potential of the current was close to the calculated equilibrium potential for Cl-(ECl=-0.9 mV). The activation of the chloride channel was dependent on the existence of the intracellular ATP. The permeability sequence of the four anions was I-≥Br->Cl->gluconate. The current was almost completely inhibited by extracellular application of chloride channel blocker tamoxifen (30 μmol/L). CONCLUSION: Antineoplastic agent cDDP can activate a chloride channel with characteristics similar to the volume-activated chloride channel in CNE-2Z cells.  相似文献   

Don't go breaking apart: Anthropogenic disturbances predict meadow fragmentation of an endangered seagrass     

Daniel S. Swadling  Greg J. West  Peter T. Gibson  Roger J. Laird  Tim M. Glasby 《水产资源保护:海洋与淡水生态系统》2023,33(1):56-69

1. Although it is well established that human activities are linked to the loss of seagrasses worldwide, the influence of anthropogenic disturbances on the habitat fragmentation of seagrass meadows is less understood. This information is essential to identify how humans are modifying seascapes and what disturbances pose the greatest risk to seagrasses, which is pertinent given the rapid urbanization occurring in coastal areas.
2. This study examined how the habitat fragmentation of an endangered seagrass Posidonia australis varied in relation to several anthropogenic disturbances (i.e. human population, marine infrastructure, terrestrial run-off and catchment land-usage) within 10 estuaries across 620 km of coastline in New South Wales, Australia.
3. When comparing between estuaries, the fragmentation of P. australis meadows was significantly greater in estuaries adjacent to highly populated metropolitan centres – generally in the Greater Sydney region. At sites within estuaries, the density of boat moorings was the most important predictor of habitat fragmentation, but there was also evidence of higher fragmentation with increased numbers of jetties and oyster aquaculture leases.
4. These results suggest that the fragmentation of seagrass meadows will become more pervasive as the human population continues to grow and estuarine development increases. Strategies to mitigate anthropogenic disturbances on seagrass meadow fragmentation could include prohibiting the construction of boat moorings and other artificial structures in areas where seagrasses are present or promoting environmentally friendly designs for marine infrastructure. This knowledge will support ongoing management actions attempting to balance coastal development and the conservation of seagrasses.

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