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| Registros recuperados: 2.489 | |
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| Loizeau, Veronique; Menesguen, Alain. |
| A five-compartment steady-state food web model is proposed for the benthic food web leading to the dab. Three exposure pathways are considered in the description of accumulation by benthic animals: ingestion of particulate contaminants associated with either sediment or phytoplankton, and respiratory uptake of free dissolved contaminant in overlaying water. Application of the model to a simple food web in the Bay of Seine (Eastern Channel) indicates that : a) feeding is the principal route of contamination, especially for PCB which have more than four chlorine atoms in the molecule ; b) excretion and growth rates, phytoplankton lipid fraction and organic carbon content of sediment are the parameters which mostly determine the chemical bioaccumulation in... |
| Tipo: Text |
Palavras-chave: MODEL; PCB; FOOD WEB; BENTHIC INVERTEBRATES; DAB. |
| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00100/21127/18747.pdf |
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| Ahrendsen, Bruce L.. |
| A dual cost function approach is developed as an alternative to time series and simplistic approaches for estimating farmers' expected operating rates of return on assets. A translog restricted cost function is estimated using data provided by 152 North Carolina dairy farmers over the period 1976 through 1986. The predicted costs from the fitted restricted cost function are used to construct estimates of farmers' expected operating rates of return on assets. The estimates from this structural approach explain more of the variation in observed rates than do time series estimates or sample mean observed rates. |
| Tipo: Journal Article |
Palavras-chave: Estimating expectations; Rate of return; Translog cost function; Agricultural Finance. |
| Ano: 1993 |
URL: http://purl.umn.edu/15042 |
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| Kaiser, Harry M.; Blayney, Donald P.. |
| The purpose of this report is to catalog, describe, and provide information concerning existing models of the dairy sector. Many types of dairy models are listed in this report. The models vary by geographic aggregation (e.g., farm, state, regional, national, and international levels), time dimension (e.g., comparative static, annual, quarterly, monthly, weekly, daily specifications), principal application (e.g., Federal Milk Marketing Order, dairy price support program, operations analysis, etc.), computer requirements (mainframe vs. micro-computer, DOS vs. Apple), ease of use, i.e., "user friendliness," and other dimensions. The report should be useful for individuals interested in the dairy industry, public policy, or quantitative methods. |
| Tipo: Technical Report |
Palavras-chave: Livestock Production/Industries. |
| Ano: 1993 |
URL: http://purl.umn.edu/123009 |
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| Maloney, Thomas R.; Milligan, Robert A.; Petracek, Kristine T.. |
| Many florist crop producers have reported difficulty with attracting qualified employees to positions within their businesses. The purpose of this study was to define the difficulties florist crop producers face in attracting qualified workers. Managers of 72 florist crop production firms in Michigan, New York, Ohio, and Pennsylvania participated in a telephone survey designed to gather information on recruitment and selection issues for florist crop producers. The survey results revealed that recruitment practices were not used as frequently as they could be. It also appeared that managers were doing a better job with the selection process than they were with the recruitment process. In addition, compensation appeared to be closely linked to the ability... |
| Tipo: Technical Report |
Palavras-chave: Crop Production/Industries. |
| Ano: 1993 |
URL: http://purl.umn.edu/123012 |
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| Vermeulen, J.J.. |
| A revision is presented of six sections of the genus Bulbophyllum (Orchidaceae): sect. Adelopetalum (mainly occurring in Australia), sect. Lepanthanthe, sect. Macrouris, sect. Pelma, sect. Peltopus, and sect. Uncifera (all mainly occurring in New Guinea). Together these include 110 species and 9 subspecies. Fortyseven species and 4 subspecies are new; they are either described in this revision or in precursors to this revision. The genus Dactylorhynchus is reduced to Bulbophyllum. Keys to the species, as well as synonymy, descriptions and illustrations of each species are provided. Some aspects of the morphology of the plants are discussed. A cladistic analysis of each revised section is given. A method to select the closest outgroup species from a number... |
| Tipo: Article / Letter to the editor |
Palavras-chave: Orchidaceae; Bulbophyllum; East Malesia; New Guinea; Australia; Cladistics; Biogeography. |
| Ano: 1993 |
URL: http://www.repository.naturalis.nl/record/509470 |
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| Vidal Espinoza, Hernán. |
| El concebir la práctica antropológica como limitada a la producción de textos etnográficos ha conducido a una nueva esencialización de la etnografía, reducíendo la política de la antropología a su poética (Abu-Lughod 1991:149, Fardon 1990:23). Esa concepción puede ser refutada inclusive desde un punto de vista estadístico. Un gran número de antropólogos hacemos o hemos hecho cosas bastante distintas que escribir etnografías y tales actividades no pueden ser separadas arbitrariamente de la definición de nuestra práctica (Fahim y Helmer 1980). Lo que es más grave, plantear que nuestra producción y nuestros productos acaban en la mera representación escrita supone aislarse artificialmente del lenguaje y las acciones de la vida cotidiana. A partir de los... |
| Tipo: Tesis de maestría |
Palavras-chave: IDENTIFICACIÓN CULTURAL; ANTROPOLOGÍA CULTURAL Y SOCIAL; INDIOS DE ARGENTINA. |
| Ano: 1993 |
URL: http://hdl.handle.net/10469/91 |
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| Vidal Espinoza, Hernán. |
| El concebir la práctica antropológica como limitada a la producción de textos etnográficos ha conducido a una nueva esencialización de la etnografía, reducíendo la política de la antropología a su poética (Abu-Lughod 1991:149, Fardon 1990:23). Esa concepción puede ser refutada inclusive desde un punto de vista estadístico. Un gran número de antropólogos hacemos o hemos hecho cosas bastante distintas que escribir etnografías y tales actividades no pueden ser separadas arbitrariamente de la definición de nuestra práctica (Fahim y Helmer 1980). Lo que es más grave, plantear que nuestra producción y nuestros productos acaban en la mera representación escrita supone aislarse artificialmente del lenguaje y las acciones de la vida cotidiana. A partir de los... |
| Tipo: Tesis de maestría |
Palavras-chave: IDENTIFICACIÓN CULTURAL; ANTROPOLOGÍA CULTURAL Y SOCIAL; INDIOS DE ARGENTINA. |
| Ano: 1993 |
URL: http://hdl.handle.net/10469/91 |
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| Morais,S.A.; Silva,R.D.M.; Domingues,M.A.C.; Fonseca,H.. |
| O experimento foi conduzido para testar a eficiência de dois alumino-silicatos, no controle da aflatoxicose em frangos de corte (machos). Foram efetuadas análises de sangue para verificação da influência da aflatoxina no perfil sanguíneo das aves. Os resultados mostraram efeito negativo (P<0,05) da aflatoxina no desempenho das aves no que se refere ao peso corporal, ganho de peso, consumo e conversão alimentares, quando comparados com o controle. Os níveis sanguíneos de proteína total se apresentaram reduzidos (P<0,05) e os da transaminase glutâmica oxalacética aumentados (P<0,05) em relação ao controle. Os níveis da fosfatase alcalina, tempo de protrombina, gama-ghitamil transferase, bilirrubina e da capacidade total de ligação do ferro não... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aflatoxina; Alumino-silicatos; Frangos de corte; Parámetros sanguíneos. |
| Ano: 1993 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161993000200020 |
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| Littaye-mariette, Anne. |
| Début 1990, l'IFREMER et les Affaires Maritimes sont contactés par un ostréiculteur de l'Aber-Benoit afin d'effectuer le constat de mortalités survenues depuis 1989 sur ses concessions. L'expertise révèle des taux de mortalité allant de 20 à 70% sur les huîtres en élevage, tous âges et toutes techniques confondues (Cl. Le Bec, 1989). Dès cette date, un gradient décroissant de mortalité est noté d'amont en aval et du chenal à la berge. Ces mortalités anormales, par comparaison avec les autres bassins ostréicoles bretons, sont également observées sur les poches expérimentales des stations de l'Aber Benoit du réseau "Huître Creuse Bretagne" (C. Le Bec, 1989). |
| Tipo: Text |
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| Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00080/19139/16734.pdf |
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| Registros recuperados: 2.489 | |
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