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We measured the vertical and horizontal movements of striped marlin (Tetrapturus audax) off the leeward coast of the Island of Hawaii between 20 November and 18 December 1992 while simultaneously gathering data on water temperature and oceanic currents. Fish movements were monitored by ultrasonic depth-sensitive transmitters, depth-temperature profiles by an expendable bathythermograph system, and oceanic current patterns by an acoustic Doppler current profiler. Like Indo-Pacific blue marlin (Makaira mazara), striped marlin near Hawaii spend >85% of their time in the mixed layer (i.e., above 90 m depth). The maximum depth for striped marlin appears to be limited by water temperatures 8 C° colder than the mixed layer, rather than by an absolute lower temperature. We also found that the horizontal displacements of some striped marlin can be strongly influenced by currents.  相似文献   
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Zhuang W  McKague B  Reeve D  Carey J 《Chemosphere》2004,54(4):467-480
Optimal conditions for extraction methods using an accelerated solvent extractor (ASE) and a Polytron homogenizer were established for quantification of (crude) lipids and extractable organochlorine (EOCl) in fish. The two methods, an ASE consecutive extraction at 55 and 100 degrees C for ground, freeze-dried filets, and a Polytron extraction at room temperature with four repetitions for ground, wet filets and with two repetitions for wet fish livers were evaluated in terms of reproducibility and comparability. With respect to lipid measurement, the two methods have comparable reproducibility and the experimental errors are relatively small compared to natural variations of fish to fish within a sampling site. For EOCl measurement, the relative standard deviation tends to increase with decreasing levels of EOCl in specimens. An important factor for the relative standard deviation of measurements of analytes present at trace levels in fish matrices is sampling error in taking aliquots. Statistical analysis using a paired comparison design showed that measurement values (crude lipids or EOCl) obtained from these two extraction methods are, in general, not equivalent. There is a good correlation between the two methods for lipid measurement; whereas for EOCl measurements, high degrees of correlation exist within the exposed fish group, but not in the reference group.  相似文献   
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This article describes the development and application of a streamlined air control and response modeling system with a novel response surface modeling-linear coupled fitting method and a new module to provide streamlined model data for PM_(2.5) attainment assessment in China.This method is capable of significantly reducing the dimensions required to establish a response surface model,as well as capturing more realistic response of PM_(2.5) to emission changes with a limited number of model simulations.The newly developed module establishes a data link between the system and the Software for Model Attainment Test—Community Edition(SMAT-CE),and has the ability to rapidly provide model responses to emission control scenarios for SMAT-CE using a simple interface.The performance of this streamlined system is demonstrated through a case study of the Yangtze River Delta(YRD) in China.Our results show that this system is capable of reproducing the Community Multi-Scale Air Quality(CMAQ) model simulation results with maximum mean normalized error 3.5%.It is also demonstrated that primary emissions make a major contribution to ambient levels of PM_(2.5) in January and August(e.g.,more than50%contributed by primary emissions in Shanghai),and Shanghai needs to have regional emission control both locally and in its neighboring provinces to meet China's annual PM_(2.5)National Ambient Air Quality Standard.The streamlined system provides a real-time control/response assessment to identify the contributions of major emission sources to ambient PM_(2.5)(and potentially O_3 as well) and streamline air quality data for SMAT-CE to perform attainment assessments.  相似文献   
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Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test—Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy.  相似文献   
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This article describes the development and implementations of a novel software platform that supports real-time, science-based policy making on air quality through a user-friendly interface. The software, RSM-VAT, uses a response surface modeling (RSM) methodology and serves as a visualization and analysis tool (VAT) for three-dimensional air quality data obtained by atmospheric models. The software features a number of powerful and intuitive data visualization functions for illustrating the complex nonlinear relationship between emission reductions and air quality benefits. The case study of contiguous U.S. demonstrates that the enhanced RSM-VAT is capable of reproducing the air quality model results with Normalized Mean Bias < 2% and assisting in air quality policy making in near real time.  相似文献   
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ABSTRACT: This study proposes that demand management through pricing policies can be used in conjunction with supply management to solve water supply problems. Economic principles are shown to apply to rural residential water use. A demand function for water was developed based on cross-sectional water use data collected in Kentucky. Price was found to be a significant determinant of the quantity of water demanded. A constant price elasticity of -0.92 was found. The demand function was used in a simulation analysis to determine reservoir capacity needed to supply water needs of a rural community. The simulation revealed that price can significantly affect required reservoir storage.  相似文献   
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