986 resultados para Total protection


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Length-weight relationships of Panulirus homarus caught from the Kanniyakumari coast was found to be W=0.000566 L super(2-50). The relationship between tail length and total length was also investigated and compared with that of Panulirus polyphagus. Same relationship did not hold good for the two sexes as in the case of P. polyphagus. For a given tail length, the head length, the total length and the weight appear to be relatively larger for females of small sizes of P. homarus.

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The development of a new mercury-free ternary aluminum anode (CIFTAL) for cathodic protection of marine structures is described. The new anode demonstrated a current efficiency of 83.5% to 85.4% in a current density range of 5.6 to 166.7 mAdmˉ². The current efficiency remained practically stable at 1.4 mAdmˉ² over a test period of 300 days. The service trials of the anode on steel trawlers and aluminum (Indal M 57 S) sheathed wooden boats have shown satisfactory performance in terms of uniform dissolution, current efficiency and driving voltage. In the wake of legislations restricting the use of anodes containing mercury in an endeavor to control the mercury pollution of the near shore aquatic environment, the new anode (CIFTAL) with its stable current output and high current efficiency merits significance in marine cathodic protection.

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The zona pellucida (ZP) enclosing the mammalian ovum is important for its protection and for initial stages of fertilization, but the role of the ZP during embryo development is less clear. This study was designed to investigate if the hamster ZP is needed for embryo development from 1-cell to blastocyst in vitro, and to compare methods for removing the ZP. A total of 395 hamster pronucleate ova were collected 10 h post activation from superovulated, mated female hamsters. The ZP was removed from some ova using either 0.05% pronase, 0.05% trypsin or acid Tyrode's solution. To prevent ZP-free ova from sticking together, they were cultured singly in 30-50 muL drops of HECM-6 culture medium together with ZP-intact ova as controls. There was no significant difference among treatment groups in embryo development to blastocyst: 36/87 (42%) in the ZP intact group; 35/75 (47%) in the pronase-treated ZP-free group; 37/74 (50%) in the trypsin-treated ZP-free group; and 37/71 (52%) in the acid-treated ZP-free group. These results indicate that 1) the ZP is unnecessary for hamster embryo development in vitro from the pronucleate ovum stage to blastocyst; 2) none of the three ZP-removal methods was detrimental to embryo development; 3) embryos do not need to be cultured in groups during in vitro development from 1-cell to blastocyst. (C) 2000 by Elsevier Science Inc.

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Highlights are given of a mangove community structure survey conducted in the coastal barangays of Carles, Panay Island, Philippines, in April 2003. The survey aimed to qualitatively describe the species composition, community structure and plant biomass of mangrove forests. The 13 sample sites showed a total of 18 mangrove species, dominated by Avicennia marina. The findings, which indicate a modest yet declining diversity of mangroves in Carles, reinforce the need for their protection and management. This is due not only to their importance as habitats for fish and shellfish juveniles that replenish stocks for capture fisheries and aquaculture, but also due to the fact that Carles is one of the few remaining areas in Panay where rare mangrove species can still be found.

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One of the most endangered populations of Black-necked Cranes (Grus nigricollis), the central population, is declining due to habitat loss and degradation, but little is known about their space use patterns and habitat preferences. We examined the space use and habitat preferences of Black-necked Cranes during the winter of 2007-2008 at the Napahai wetland in northwest Yunnan, China, where approximately 300 Black-necked Cranes (>90% of the total central population) spent the winter. Euclidean distance analysis was employed to determine the habitat preferences of Black-necked Cranes, and a local nearest-neighbor, convex-hull construction method was used to examine space use. Our results indicate that Black-necked Cranes preferred shallow marsh and wet meadow habitats and avoided farmland and dry grassland. Core-use areas (50% isopleths) and total-use areas (100% isopleths) accounted for only 1.2% and 28.2% of the study area, respectively. We recommend that habitat protection efforts focus on shallow marsh and wet meadow habitats to maintain preferred foraging sites. Core-use areas, such as the primary foraging areas of Black-necked Cranes, should be designated as part of the core zone of the nature reserve. Monthly shifts in the core-use areas of the cranes also indicate that the reserve should be large enough to permit changes in space use. In addition to preserving habitat, government officials should also take measures to decrease human activity in areas used by foraging Black-necked Cranes.

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Purpose - The purpose of this paper is to develop a framework of total acquisition cost of overseas outsourcing/sourcing in manufacturing industry. This framework contains categorized cost items that may occur during the overseas outsourcing/sourcing process. The framework was tested by a case study to establish both its feasibility and usability. Design/methodology/approach - First, interviews were carried out with practitioners who have the experience of overseas outsourcing/sourcing in order to obtain inputs from industry. The framework was then built up based on combined inputs from literature and from practitioners. Finally, the framework was tested by a case study in a multinational high-tech manufacturer to establish both its feasibility and usability. Findings - A practical barrier for implementing this framework is shortage of information. The predictability of the cost items in the framework varies. How to deal with the trade off between accuracy and applicability is a problem needed to be solved in the future research. Originality/value - There are always limitations to the generalizations that can be made from just one case. However, despite these limitations, this case study is believed to have shown the general requirement of modeling the uncertainty and dealing with the dilemma between accuracy and applicability in practice. © Emerald Group Publishing Limited.

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Avalanche multiplication has been one of the major destructive failure mechanisms in IGBTs; in order to avoid operating an IGBT under abnormal conditions, it is desirable to develop peripheral protecting circuits monolithically integrated without compromising the operation and performance of the IGBT. In this paper, a monolithically integrated avalanche diode (D av) for 600V Trench IGBT over-voltage protection is proposed. The mix-mode transient simulation proves the clamping capability of the D av when the IGBT is experiencing over-voltage stress in unclamped inductive switching (UIS) test. The spread of avalanche energy, which prevents hot-spot formation, through the help of the avalanche diode feeding back a large fraction of the avalanche current to a gate resistance (R G) is also explained. © 2011 IEEE.

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A newly developed computer model, which solves the horizontal two-dimensional Boussinesq equations using a total variation diminishing Lax-Wendroff scheme, has been used to study the runup of solitary waves, with various heights, on idealized conical islands consisting of side slopes of different angles. This numerical model has first been validated against high-quality laboratory measurements of solitary wave runups on a uniform plane slope and on an isoliated conical island, with satisfactory agreement being achieved. An extensive parametric study concerning the effects of the wave height and island slope on the solitary wave runup has subsequently been carried out. Strong wave shoaling and diffraction effects have been observed for all the cases investigated. The relationship between the runup height and wave height has been obtained and compared with that for the case on uniform plane slopes. It has been found that the runup on a conical island is generally lower than that on a uniform plane slope, as a result of the two-dimensional effect. The correlation between the runup with the side slope of an island has also been identified, with higher runups on milder slopes. This comprehensive study on the soliton runup on islands is relevant to the protection of coastal and inland regions from extreme wave attacks. © the Coastal Education & Research Foundation 2012.

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This book provides you with all fundamental concepts, guidelines and tools to ensure core business information is identified, protected and used effectively, written in a language that is clear and easy to understand for non-technical ...

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The concepts of reliability, robustness, adaptability, versatility, resilience and flexibility have been used to describe how a system design can mitigate the likely impact of uncertainties without removing their sources. With the increasing number of publications on designing systems to have such ilities, there is a need to clarify the relationships between the different ideas. This short article introduces a framework to compare these different ways in which a system can be insensitive to uncertainty, clarifying their meaning in the context of complex system design. We focus on relationships between the ilities listed above and do not discuss in detail methods to design-for-ilities. © 2013 The Author(s). Published by Taylor & Francis.

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Microcystins (MCs) comprise a family of more than 80 related cyclic hepatotoxic heptapeptides. Oxidation of MCs causes cleavage of the chemically unique C-20 beta-amino acid (2S, 3S, 8S, 9S)-3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca-4,6-dienoic acid (Adda) amino to form 2-methyl-3-methoxy-4-phenylbutanoic acid (MMPB), which has been exploited to enable analysis of the entire family. In the present study, the reaction conditions (e.g. concentration of the reactants. temperature and pH) used in the production of MMPB by oxidation of cyanobacterial samples with permanganate-periodate were optimized through a series of well-controlled batch experiments. The oxidation product (MMPB) was then directly analyzed by high-performance liquid chromatography with diode array detection. The results of this study provided insight into the influence of reaction conditions on the yield of MMPB. Specifically, the optimal conditions, including a high dose of permanganate (>= 50 mM) in saturated periodate solution at ambient temperature under alkaline conditions (pH similar to 9) over 1-4 h were proposed, as indicated by a MMPB yield of greater than 85%. The technique developed here was applied to determine the total concentration of MCs in cyanobacterial bloom samples, and indicated that the MMPB technique was a highly sensitive and accurate method of quantifying total MCs. Additionally, these results will aid in development of a highly effective analytical method for detection of MMPB as an oxidation product for evaluation of total MCs in a wide range of environmental sample matrices, including natural waters, soils (sediments) and animal tissues. (C) 2009 Elsevier B.V. All rights reserved.