350 research outputs found
Alternate Solutions to Water Resource Development -- A Case Study
This study was undertaken in an effort to develop procedural methodology for the consideration of alternative solutions for water resources development in a short period of time with a view toward reduction of total costs involved in prefeasibility studies. A review of related literature was made to reveal the status of the need for the development of a comprehensive method to evaluate possible alternatives.
Three techniques were developed in this research effort to estimate the investment costs of a reservoir project, a levee project, and a basin conservation reservoir project in an economic region. The application of the methodologies were illustrated by a case study. The cost of a reservoir project in the case study area determined by the method developed in this investigation was in excellent agreement with the Corps of Engineers' estimate using conventional methods. In general, the dependability of all the three methodologies were considered good for use in order-ofmagnitude estimates.
Selected solutions for water resources development problems in the Navasota River watershed were analyzed. The cost of water supply by desalination in the service area of the proposed Millican reservoir was computed following the procedure recommended by the Office of Saline Water. The investment costs of the alternatives were compared. The multipurpose reservoir project for flood control, water supply and recreation was found to be the least costly project. However, levees for flood protection in the lower Brazos River basin and desalting for water supply appeared to possess more intangible environmental benefits although the estimated cost of this multipurpose alternative was somewhat higher in comparison to the multipurpose reservoir project.
Evaluation of intangible cost factors (environmental, aesthetic, etc.) was not possible in want of scientifically amenable procedures. Total costs (combined tangible and intangible factors) of all alternative plans could not be estimated. As a result, no attempt was made to recommend any specific alternative to the proposed action in the case study area
General Statistical properties of the CMB Polarization field
The distribution of the polarization of the Cosmic Microwave Background (CMB)
in the sky is determined by the hypothesis of random Gaussian distribution of
the primordial density perturbations. This hypotheses is well motivated by the
inflationary cosmology. Therefore, the test of consistency of the statistical
properties of the CMB polarization field with the Gaussianity of primordial
density fluctuations is a realistic way to study the nature of primordial
inhomogeneities in the Universe. This paper contains the theoretical
predictions of the general statistical properties of the CMB polarization
field. All results obtained under assumption of the Gaussian nature of the
signal. We pay the special attention to the following two problems. First, the
classification and statistics of the singular points of the polarization field
where polarization is equal to zero. Second, the topology of contours of the
value of the degree of polarization. We have investigated the percolation
properties for the zones of ``strong'' and ``weak'' polarization. We also have
calculated Minkowski functionals for the CMB polarization field. All results
are analytical.Comment: Latex, 22 pages, including 5 figure
The Role of Trait and State Perfectionism in Psychological Detachment From Daily Job Demands
Psychological detachment has been proposed to be a mediator of the relations between an individual's responses to stressful work-related experiences and mid- and long-term health. However, the number of studies that have specifically examined the role that personal characteristics play in these associations is considerably small. One personal characteristic that might specifically interfere with psychological detachment is perfectionism, which has been considered an important vulnerability factor for the development of psychological disorders. Hence, the goal of this registered report was to extend research on psychological detachment by introducing trait and state perfectionism as moderators of the aforementioned relations. We conducted an experience sampling study with three measurement occasions per day over the course of 3 working weeks (N = 158 employees; Mage = 41.6; 67% women). Multilevel path models showed that perfectionistic concerns consistently determined strain responses at between- and within-levels of analyses even after the effects of job demands (i.e., unfinished tasks and role ambiguity) and detachment were accounted for. However, we found no evidence for the proposed moderation effects. The theoretical implications for the understanding of the processes proposed in the stressor-detachment model are discussed
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Marine and Hydrokinetic Renewable Energy Technologies: Potential Navigational Impacts and Mitigation Measures
On April 15, 2008, the Department of Energy (DOE) issued a Funding Opportunity Announcement for Advanced Water Power Projects which included a Topic Area for Marine and Hydrokinetic Renewable Energy Market Acceleration Projects. Within this Topic Area, DOE identified potential navigational impacts of marine and hydrokinetic renewable energy technologies and measures to prevent adverse impacts on navigation as a sub-topic area. DOE defines marine and hydrokinetic technologies as those capable of utilizing one or more of the following resource categories for energy generation: ocean waves; tides or ocean currents; free flowing water in rivers or streams; and energy generation from the differentials in ocean temperature. PCCI was awarded Cooperative Agreement DE-FC36-08GO18177 from the DOE to identify the potential navigational impacts and mitigation measures for marine hydrokinetic technologies, as summarized herein. The contract also required cooperation with the U.S. Coast Guard (USCG) and two recipients of awards (Pacific Energy Ventures and reVision) in a sub-topic area to develop a protocol to identify streamlined, best-siting practices. Over the period of this contract, PCCI and our sub-consultants, David Basco, Ph.D., and Neil Rondorf of Science Applications International Corporation, met with USCG headquarters personnel, with U.S. Army Corps of Engineers headquarters and regional personnel, with U.S. Navy regional personnel and other ocean users in order to develop an understanding of existing practices for the identification of navigational impacts that might occur during construction, operation, maintenance, and decommissioning. At these same meetings, âstandardâ and potential mitigation measures were discussed so that guidance could be prepared for project developers. Concurrently, PCCI reviewed navigation guidance published by the USCG and international community. This report summarizes the results of this effort, provides guidance in the form of a checklist for assessing the navigational impacts of potential marine and hydrokinetic projects, and provides guidance for improving the existing navigational guidance promulgated by the USCG in Navigation Vessel Inspection Circular 02 07. At the request of the USCG, our checklist and mitigation guidance was written in a generic nature so that it could be equally applied to offshore wind projects. PCCI teleconferenced on a monthly basis with DOE, Pacific Energy Ventures and reVision in order to share information and review work products. Although the focus of our effort was on marine and hydrokinetic technologies, as defined above, this effort drew upon earlier work by the USCG on offshore wind renewable energy installations. The guidance provided herein can be applied equally to marine and hydrokinetic technologies and to offshore wind, which are collectively referred to by the USCG as Renewable Energy Installations
World Antimalarial Resistance Network (WARN) II: In vitro antimalarial drug susceptibility
Intrinsic resistance of Plasmodium falciparum is clearly a major determinant of the clinical failure of antimalarial drugs. However, complex interactions between the host, the parasite and the drug obscure the ability to define parasite drug resistance in vivo. The in vitro antimalarial drug susceptibility assay determines ex-vivo growth of parasite in the presence of serial drug concentrations and, thus, eliminates host effects, such as drug metabolism and immunity. Although the sensitivity of the parasite to various antimalarials provided by such a test provides an important indicator of intrinsic parasite susceptibility, there are fundamental methodological issues that undermine comparison of in vitro susceptibility both between laboratories and within a single laboratory over time. A network of laboratories is proposed that will agree on the basic parameters of the in vitro test and associated measures of quality control. The aim of the network would be to establish baseline values of sensitivity to commonly used antimalarial agents from key regions of the world, and create a global database, linked to clinical, molecular and pharmacology databases, to support active surveillance to monitor temporal trends in parasite susceptibility. Such a network would facilitate the rapid detection of strains with novel antimalarial resistance profiles and investigate suitable alternative treatments with retained efficacy
The feasibility of milkfish (Chanos chanos) aquaculture in Solomon Islands
Fish is crucial to food and nutrition security in Solomon Islands, and demand is expected to increase due to a growing population. However, it is projected that current capture fisheries production will not meet this growing demand. Aquaculture has the potential to mitigate the capture fishery shortfall, and the Government of Solomon Islands is prioritizing aquaculture as a solution to meet future food and income needs. Aquaculture in Solomon Islands is still in early development. Mozambique tilapia (Oreochromis mossambicus) is farmed for household consumption, but its prolific reproductive rate and resulting slow growth limit its potential as a commercial aquaculture species. More productive fish species that are not indigenous to Solomon Islands but are successfully farmed overseas could be introduced; however, such a decision needs to take into account the potential ecological or social impacts. For land-based pond aquaculture, the only indigenous species that has been farmed extensively elsewhere is milkfish (Chanos chanos). This report presents a feasibility assessment for milkfish farming in Solomon Islands. It synthesizes the current knowledge about milkfish farming and presents results of a 4-year study on the potential for milkfish aquaculture in Solomon Islands
Agricultural subsidies in the United States and their effect on two annual Chilean crops: corn and wheat
Efficacy and tolerability of four antimalarial combinations in the treatment of uncomplicated Plasmodium falciparum malaria in Senegal
<p>Abstract</p> <p>Background</p> <p>In view of the high level of chloroquine resistance in many countries, WHO has recommended the use of combination therapy with artemisinin derivatives in the treatment of uncomplicated malaria due to <it>Plasmodium falciparum</it>. Four antimalarial drug combinations, artesunate plus amodiaquine (Arsucam<sup>Âź</sup>), artesunate plus mefloquine (Artequin<sup>Âź</sup>), artemether plus lumefantrine (Coartem<sup>Âź</sup>; four doses and six doses), and amodiaquine plus sulphadoxine-pyrimethamine, were studied in five health districts in Senegal.</p> <p>Methods</p> <p>This is a descriptive, analytical, open, randomized study to evaluate the efficacy and tolerability of these four antimalarial combinations in the treatment of uncomplicated falciparum malaria using the 2002 WHO protocol.</p> <p>Results</p> <p>All drug combinations demonstrated good efficacy. On day 28, all combinations resulted in an excellent clinical and parasitological response rate of 100% after correction for PCR results, except for the four-dose artemether-lumefantrine regimen (96.4%). Follow-up of approximately 10% of each treatment group on day 42 demonstrated an efficacy of 100%.</p> <p>The combinations were well tolerated clinically and biologically. No unexpected side-effect was observed and all side-effects disappeared at the end of treatment. No serious side-effect requiring premature termination of treatment was observed.</p> <p>Conclusion</p> <p>The four combinations are effective and well-tolerated.</p
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