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131.
132.
Yaron Zalel Ofer Lehavi Eyal Schiff Bruria Shalmon Shlomi Cohen Adrian Schulman Reuven Achiron 《黑龙江环境通报》2002,22(7):553-557
Shortened fetal long bones (SFLB) are usually indicative of a skeletal dysplasia. Our aim in this observational retrospective study was to describe a new association between SFLB, small for gestational age (SGA) fetuses and placental abnormalities, and to suggest an aetiologic explanation. During the last decade we have evaluated nine cases in which SFLB (more than 2SD below the mean) was associated with SGA, abnormal maternal serum placental hormones and abnormal placental sonography. Six cases had significantly increased second trimester maternal serum βhCG and four developed toxaemia of pregnancy or had chronic hypertension. On histology, mature placentas with vascular abnormalities, including chorangiosis, large infarcts and slightly increased syncytial knots were noted. The combination of SFLB, SGA fetuses and placental abnormalities (sonographic, as well as histological) suggested a possible common pathway in the aetiology of this association. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
133.
Gayathri Prabhakar Stuart Schwartz Elizabeth Waters Cecile Punzalan Maimon M. Cohen 《黑龙江环境通报》1994,14(7):595-598
Karyotypic discrepancy among four different cell types is described in tissues derived from a pregnancy terminated because of chromosomal anomalies. Chorionic villus cells demonstrated 46,XX (direct preparation) and 46, XX/47,XX,+marl (cultured cells) karyotypes, while fetal skin fibroblasts had a karyotype of 47,XX,+ 18 and the placenta showed a triple mosaicism of 47,XX, + 18/47,XX,+mar1/48,XX,+ 18,+mar2. The origin of this complex chromosomal distribution and its significance are discussed in comparison with findings in similar cases. 相似文献
134.
135.
Changes in human behavior are a precursor to measurable impacts of no-take marine reserves. We investigated changes in recreational fishing site selection in response to the 2005 announcement of enforcement in a marine reserve in the Gulf of California, Mexico. We used a novel data set of daily self-reported boating destinations from emergency rescue logbooks for a recreational angling community from 2000 to 2008. Because the reserve system has no experimental control, we modeled the data two ways to test for robustness to model specification. We tested for changes in human fishing behavior with regression and fit a fleet-level discrete choice model to project a. counterfactual scenario. The counterfactual is the statistically constructed ex post expectation of the human behavior we would have observed if the reserve never existed. We included month and year fixed effects in our models to account for seasonal and interannual fluctuations in fishing behavior and catch rates. We detected a decrease in reserve use compared to the counterfactual, indicating that the reserve rapidly experienced a decrease in visitation. However, the reserve's effect to reduce trips diminished with time. These results indicate that the reserve is unlikely to meet its ecological goals without institutional changes that enhance compliance. This illustrates the value of human use data to understanding the processes underlying marine reserve function. We suggest that managers should consider human use with the same frequency, rigor, and tools as they do fishery stocks. Marine reserves directly affect people, and understanding human behavioral responses to marine reserves is an important step in marine reserve management. 相似文献
136.
137.
Rizzuti AM Cohen AD Hunt PG Ellison AQ 《Journal of environmental science and health. Part. B》2002,37(6):587-611
This paper reports on research designed to test the hypothesis that differences in peat composition will cause differences in amounts of N and P retained during contact with liquid swine manure (LSM) and liquid poultry manure (LPM). Peat types representing a wide range of properties were tested in order to establish which chemical and physical properties might be most indicative of their capacities to retain N and P from LSM and LPM. Eight-percent slurries (peat/LSM and peat/LPM) were measured for total nitrogen (TKN) and total phosphorous (TP) after 6, 24 and 96 hours. Tests were done to determine the TKN and TP contents of these peats, the LSM, and the LPM, both before and after they were mixed together. The N and P retention results revealed that most peats worked reasonably well at retaining N and P from either LSM or LPM. However, some peats were more effective than others. These peats also decreased the N and P levels in the liquid portion of the LSM. Peats with higher N retention capacities tended to have lower ash contents, but higher macroporosities and total cellulose contents. Peats with higher P retention capacities tended to have lower bulk densities, ash contents, total guaiacyl lignins contents, fulvic acids contents, but higher microporosities, macroporosities, H contents, and total cellulose contents. Peats with higher N and P retention capacities also had humic acid contents between 5-7%. The results of this study suggest that if these peats are used to reduce odors and N and P contamination, possible byproducts could be the production of odorless fertilizers. 相似文献
138.
Marvin J Dainoff Arne Aar?s Ola Ro Barbara G F Cohen 《International journal of occupational safety and ergonomics》2005,11(1):3-8
The MEPS (musculoskeletal--eyestrain--psychosocial--stress) study involved an extensive degree of multidisciplinary and multicultural cooperation. The objective was to examine the effects of multiple ergonomic interventions on visual, musculoskeletal, postural, and psychosocial outcomes amongst operators of visual display terminals (VDTs). The inherent complexity of a comprehensive ergonomic investigation requires participation of researchers from a variety of disciplines, as well as comparisons among populations with different geographical and cultural backgrounds. The design and execution of the resulting research protocol presents a number of challenges. This paper discusses the advantages and pitfalls associated with multidisciplinary multinational cooperation. Advantages include the necessity for development of a common language and perspective providing a basis for future collaboration. Pitfalls include logistic and coordination difficulties associated with conducting standardized procedures in different locations, as well as the inherent potential for professional conflict. It is argued that such pitfalls ought to be understood and integrated into the project planning process. 相似文献
139.
Marvin J Dainoff Arne Aar?s Gunnar Horgen Maria Konarska Stig Larsen Magne Thoresen Barbara G F Cohen 《International journal of occupational safety and ergonomics》2005,11(1):9-23
This special issue of the International Journal of Occupational Safety and Ergonomics (JOSE) reports the results from an extensive multinational and multidisciplinary collaborative investigation of the impacts on visual display terminal (VDT) work of musculoskeletal, visual, ergonomic, and psychosocial factors. For brevity, this effort has been referred to as the MEPS project (musculoskeletal--eyestrain--psychosocial--stress). This paper lays out the basic methodological structure of the study. The study was conducted in 4 countries utilizing VDT data entry workers as the primary subject population. A battery of objective and subject assessment measures, including muscle load, visual function, physical and visual strain, postural, ergonomic and psychosocial factors, were assessed at 3 different points in time. A pre-test was given prior to an ergonomic intervention. Two post-tests were given 1 month and 1 year after the ergonomic intervention. 相似文献
140.
Maxwell Cohen 《Natural resources forum》1982,6(3):247-261
From a discussion of the main objectives of river basin planning, the author develops the elements needed to assure successful river basin planning at the multinational level. Functions of some existing international river basin commissions are described and a fourfold classification based on the degree of planning undertaken is proposed. The Canada—United States experience in river basin planning is placed in a historical framework and the political, legal and economic factors which influenced the operations of the Canada—US International Joint Commission are described. The central point about Canada—US experience appears to be that direct planning is less frequent than indirect “planning.” The two main functions of the Canada—US International Joint Commission are regulation on the one hand and dispute settlement on the other. Partant d'une discussion sur les principaux objectifs de la planification des bassins fluviaux, l'auteur analyse les éléments nécessaires à la planification efficace de ces bassins au niveau multinational. II décrit les fonctions de certaines commissions internationales de bassins fluviaux et propose une classification en quatre parties basée sur le degré de planification envisagé. L'auteur situe les travaux du Canada et des Etats-Unis en matière de planification de bassins fluviaux dans un contexte historique et analyse les facteurs politiques, juridiques et économiques qui influencent les activités de la Commission internationale mixte du Canada et des Etats-Unis. Le résultat principal des travaux de cette Commission semble être que la planification directe est plus rare que la planification indirecte. Les deux fonctions principales de la Commission sont la réglementation d'une part et le règlement de disputes de l'autre. Después de discutir los objetivos principales la Planificación de Cuencas Hidrográficas, el autor desarrolla los elementos necesarios para asegurar una planificación apropiada de cuencas a nivel multinacional. Se describen las funciones de algunas Comisiones de Cuencas Internacionales y se propone una clasificación basado en el grado de planificación emprendida. Se pone en un marco histórico la experiencia de Canadá y los Estados Unidos en materia de planficación de cuencas hydrográficas y se describen los factores politicos, legales y económicos que influenciaron las operaciones de la Comisión Conjunta Internacional Canadá-Estados Unidos. El punto central de la experiencia Canadá—Estados Unidos parece ser que la planificación directa es menos frecuente que la “planificación indirecta.” Las funciones principales de esta comisión son establecer regulaciones y dar solución a las disputas existentes. 相似文献