995 resultados para 19-191


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This study owes its inception to the wisdom and experience of the staff of the Northeast Fisheries Science Center who, after several decades of surveys in the New York Bight, recognized a unique opportunity to capitalize on the decision to stop ocean dumping of sewage sludge and designed an innovative field study to evaluate effects on living marine resources and their habitats. For decades ocean dumping was viewed as a cheap and effective means for disposal of wastes generated by urbanized coastal areas. Even after the 12-mile site was closed, sewage sludge continued to be dumped at Deepwater Dumpsite 106. The 6-mile site off the NewJersey coast is still used as a dumpsite for dredged material from New York Harbor areas. Discussions continue on the propriety of using the deep ocean spaces for disposal of a variety of material including low level radioactive wastes. Consequently, managers are still faced with critical decisions in this area. It is to be hoped that the results from the 12-mile study will provide the necessary information on which these managers can evaluate future risks associated with ocean waste disposal. (PDF file contains 270 pages.)

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Female reproduction in penaeid shrimp is carefully regulated by several different endocrine factors. Their precise modes of action have not yet been fully elucidated. Three endocrine factors, each representing a different chemical class of hormones, have been investigated in the penaeid shrimp Sicyonia ingentis in our laboratory: ecdysteroids, vitellogenesis-inhibiting hormone (VIH) , and methyl farnesoate (MF). Ecdysteroids (the steroid molting hormones of arthropods; predominantly 20-hydroxyecdysone), are initially present in low levels (<10 ng/mg) in shrimp embryos. As development of the embryos nears time of hatch, the ecdysteroid levels increase to approximately 150 ng/ mg, indicating that they may be of embryonic origin and involved in embryonic development. An assay was developed for shrimp VIH, which presumably is a protein. Delay of onset of the next reproductive cycle was observed following injection of sinus gland extracts into shrimp that had previously had their eyestalks removed. A photoaffinity analog was synthesized for the putative shrimp reproductive hormone MF-a terpenoid. This analog, farnesyl diazomethyl ketone (FDK) , was used to demonstrate the presence of specific binding proteins for MF in shrimp hemolymph. (PDF file contains 136 pages.)

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The authors investigated various life history aspects of 19 rockfish species (Sebastes chlorostictus, S. constellatus, S. dalli, S. elongatus, S. ensifer, S. entomelas, S. flavidus, S. goodei, S. hopkinsi, S. levis, S. melanostomus, S. miniatus, S. ovalis, S. paucispinis, S. rosaceus, S. rosenblatti, S. rufus, s. saxicola, S. semicinctus) from the southern California Bight. These aspects included depth distribution, age-length relationships (of 7 species), length-weight relationships, size at first maturity, spawning season, and fecundity. Growth rates of female S. elongatus, S. hopkinsi, S. ova/is, S. saxicola, and S. semicinctus were higher than male conspecifics. Multiple spawning per season was found in 12 species. Generally, most species spawned between late winter and early summer, though there was some spawning within the genus throughout the year. Spawning season duration ranged from 2 (S. flavidus) to 10 months (S. paucispinis). Spawning seasons tended to start earlier in the year and be of longer duration in the southern California Bight, compared to published data on central California conspecifics. Males matured at a smaller length in 7 of the 17 species studied. Maximum fecundities ranged from 18,000 (S. dalll) to about 2,680,000 (S. levis). (PDF file contains 44 pages.)

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The United States and Japanese counterpart panels on aquaculture were formed in 1969 under the United States-Japan Cooperative Program in Natural Resources (UJNR). The panels currently include specialists drawn from the federal departments most concerned with aquaculture. Charged with exploring and developing bilateral cooperation, the panels have focused their efforts on exchanging information related to aquaculture which could be of benefit to both countries. The UJNR was started by a proposal made during the Third Cabinet-Level Meeting of the Joint United States-Japan Committee on Trade and Economic Affairs in January 1964. In addition to aquaculture, current subjects in the program are desalination of seawater, toxic microorganisms, air pollution, energy, forage crops, national park management, mycoplasmosis, wind and seismic effects, protein resources, forestry, and several joint panels and committees in marine resources research, development, and utilization. Accomplishments include: Increased communications and cooperation among technical specialists; exchanges of information, data, and research findings; annual meetings of the panels, a policy coordinative body; administrative staff meetings; exchanges of equipment, materials, and samples; several major technical conferences; and beneficial effects on international relations. (PDF file contains 108 pages.)

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The Alliance for Coastal Technologies (ACT) Workshop entitled, "Biological Platforms as Sensor Technologies and their Use as Indicators for the Marine Environment" was held in Seward, Alaska, September 19 - 21,2007. The workshop was co-hosted by the University of Alaska Fairbanks (UAF) and the Alaska SeaLife Center (ASLC). The workshop was attended by 25 participants representing a wide range of research scientists, managers, and manufacturers who develop and deploy sensory equipment using aquatic vertebrates as the mode of transport. Eight recommendations were made by participants at the conclusion of the workshop and are presented here without prioritization: 1. Encourage research toward development of energy scavenging devices of suitable sizes for use in remote sensing packages attached to marine animals. 2. Encourage funding sources for development of new sensor technologies and animal-borne tags. 3. Develop animal-borne environmental sensor platforms that offer more combined systems and improved data recovery methodologies, and expand the geographic scope of complementary fixed sensor arrays. 4. Engage the oceanographic community by: a. Offering a mini workshop at an AGU ocean sciences conference for people interested in developing an ocean carbon program that utilizes animal-borne sensor technology. b. Outreach to chemical oceanographers. 5. Min v2d6.sheepserver.net e and merge technologies from other disciplines that may be applied to marine sensors (e.g. biomedical field). 6. Encourage the NOAA Permitting Office to: a. Make a more predictable, reliable, and consistent permitting system for using animal platforms. b. Establish an evaluation process. c. Adhere to established standards. 7. Promote the expanded use of calibrated hydrophones as part of existing animal platforms. 8. Encourage the Integrated Ocean Observing System (IOOS) to promote animal tracking as effective samplers of the marine environment, and use of animals as ocean sensor technology platforms. [PDF contains 20 pages]

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The co-organized Alliance for Coastal Technologies (ACT) and National Data Buoy Center (NDBC) Workshop "Meteorological Buoy Sensors Workshop" convened in Solomons, Maryland, April 19 to 21,2006, sponsored by the University of Maryland Center for Environmental Science (UMCES) Chesapeake Bay Laboratory (CBL), an ACT partner institution. Participants from various sectors including resource managers and industry representatives collaborated to focus on technologies and sensors that measure the near surface variables of wind speed and direction, barometric pressure, humidity and air temperature. The vendor list was accordingly targeted at companies that produced these types of sensors. The managers represented a cross section of federal, regional and academic marine observing interests from around the country. Workshop discussions focused on the challenges associated with making marine meteorological observations in general and problems that were specific to a particular variable. Discussions also explored methods to mitigate these challenges through the adoption of best practices, improved technologies and increased standardization. Some of the key workshop outcomes and recommendations included: 0cean.US should establish a committee devoted to observations. The committee would have a key role in developing observing standards. The community should adopt the target cost, reliability and performance standards drafted for a typical meteorological package to be used by a regional observing system. A forum should be established to allow users and manufacturers to share best practices for the employment of marine meteorological sensors. The ACT website would host the forum. Federal activities that evaluate meteorological sensors should make their results publicly available. ACT should extend their evaluation process to include meteorological sensors. A follow on workshop should be conducted that covers the observing of meteorological variables not addressed by this workshop. (pdf contains 18 pages)

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Lei nº 8.080, de 19 de setembro de 1990 (Lei Orgânica do SUS), que dispõe sobre as condições para a promoção, proteção e recuperação da saúde, a organização e o funcionamento dos serviços correspondentes e dá outras providências, e legislação correlata. Atualizada até 13/10/2015.

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The Vancouver Lake Pilot Dredge Study revealed concentrations of certain chemicals which could be of concern: the metals copper, zinc and mercury and the pesticides lindane and aldrin were found in significant amounts. (PDF contains 1 page)

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When dissolved in water, compounds of nitrogen and phosphorus ought to contain the basic assimilated food requirements for autotrophic plants and therefore autotrophic algae. This article summarises the occurrence of nitrogen in water, how species of algae utilize nitrogen and phosphorus forms for growth and the capacities of algae to adapt to environments of different nutrient wealth. This topic has unquestionable importance not only for the purpose of survival of a species but also in deciding indirectly about the stability of ecosystems.

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We know very little about the role of birds in different ecosystems, despite numerous interesting works of researchers and amateur ornithologist scattered throughout the world. Less attention is paid to freshwater ecosystems because of the difficulties encountered in the experimental methods as well as a lack of interest on behalf of hydrobiologists, for the activities of birds in these ecosystems. This article summarises types and morphoecological forms of waterfowl and their place in the lake ecosystem.

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It is known that the larvae of Chironomidae in the first stages of life after leaving the egg case, swim for a long time in a body of water. Positive reaction in light, the capability of directed swimming and passive floating in suspension allow the larvae to temporarily carry out a planktonic way of life. This study describes the behaviour of Chironomus dorsalis larvae after leaving the egg case. The feeding of chironomid larvae in the first stages of development was also described.

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Taxonomic observations on the larval forms of Cyclops leuckarti are being discussed and compared with Cyclops oithonoides var. hyalina. Observations include Nauplius and Metanauplius stages. The author concludes that specific differences are recognisable even in the nauplius stages.

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Recent histochemical and histophysiological research on the skin of fish has posed interesting problems both with regard to the presence of specialized types of cell and with regard to the function of this organ. The present paper intends to study the development and the functional differentiation of the trout's skin, both from the histomorphological and the histochemical point of view. The skin of Salmonids is devoid of specialized cells; the granular cells of Petromyzonti, the serous cells of Selacii and the clavate cells described in many other teleosts and it lacks keratin. As such it can be considered a good working model which can be used to show the eventual histomorphological and histochemical changes occurring both in the transformation from the endovular to the aqueous environment. Histomorphological observations were carried out demonstrate the great structural simplicity of the trout's skin at all stages. The article concludes that glycogen increases greatly when the epidermis thickens and therefore when it becomes necessary to guarantee resistance, amongst which is a support mechanism.