997 resultados para Hassler Expedition
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no.8, pts.1-2 (1874-1875)
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Research into the human dynamics of expeditions is a potentially rewarding and fruitful area of study. However, the complex nature of expedition work presents the researcher with numerous challenges. This paper presents a personal reflection on the challenges linked to determining appropriate methodological processes for a study into expedition teamwork. Previous expedition research is outlined and reviewed for appropriateness. Some alternative methodological theories are described and limitations highlighted. Lastly the actual data gathering and analysis processes are detailed. The aim being to show that what happened in the field inevitably dictated how methodological processes were adapted. Essentially the paper describes a personal journey into research. A journey that sparked numerous personal insights in the science of human dynamics and expeditions and one that I hope will add to the development of expedition research in general.
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IODP Expedition 339 drilled five sites in the Gulf of Cadiz and two off the west Iberian margin (November 2011 to January 2012), and recovered 5.5 km of sediment cores with an average recovery of 86.4%. The Gulf of Cadiz was targeted for drilling as a key location for the investigation of Mediterranean outflow water (MOW) through the Gibraltar Gateway and its influence on global circulation and climate. It is also a prime area for understanding the effects of tectonic activity on evolution of the Gibraltar Gateway and on margin sedimentation. We penetrated into the Miocene at two different sites and established a strong signal of MOW in the sedimentary record of the Gulf of Cadiz, following the opening of the Gibraltar Gateway. Preliminary results show the initiation of contourite deposition at 4.2–4.5 Ma, although subsequent research will establish whether this dates the onset of MOW. The Pliocene succession, penetrated at four sites, shows low bottom current activity linked with a weak MOW. Significant widespread unconformities, present in all sites but with hiatuses of variable duration, are interpreted as a signal of intensified MOW, coupled with flow confinement. The Quaternary succession shows a much more pronounced phase of contourite drift development, with two periods of MOW intensification separated by a widespread unconformity. Following this, the final phase of drift evolution established the contourite depositional system (CDS) architecture we see today. There is a significant climate control on this evolution of MOW and bottom-current activity. However, from the closure of the Atlantic–Mediterranean gateways in Spain and Morocco just over 6 Ma and the opening of the Gibraltar Gateway at 5.3 Ma, there has been an even stronger tectonic control on margin development, downslope sediment transport and contourite drift evolution. The Gulf of Cadiz is the world's premier contourite laboratory and thus presents an ideal testing ground for the contourite paradigm. Further study of these contourites will allow us to resolve outstanding issues related to depositional processes, drift budgets, and recognition of fossil contourites in the ancient record on shore. The expedition also verified an enormous quantity and extensive distribution of contourite sands that are clean and well sorted. These represent a relatively untapped and important exploration target for potential oil and gas reservoirs.
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Montserrat now provides one of the most complete datasets for understanding the character and tempo of hazardous events at volcanic islands. Much of the erupted material ends up offshore, and this offshore record may be easier to date due to intervening hemiplegic sediments between event beds. The offshore dataset includes the first scientific drilling of volcanic island landslides during IODP Expedition 340, together with an unusually comprehensive set of shallow sediment cores and 2-D and 3-D seismic surveys. Most recently in 2013, Remotely Operated Vehicle (ROV) dives mapped and sampled the surface of the main landslide deposits. This contribution aims to provide an overview of key insights from ongoing work on IODP Expedition 340 Sites offshore Montserrat.Key objectives are to understand the composition (and hence source), emplacement mechanism (and hence tsunami generation) of major landslides, together with their frequency and timing relative to volcanic eruption cycles. The most recent major collapse event is Deposit 1, which involved ~1.8 km cubed of material and produced a blocky deposit at ~12-14ka. Deposit 1 appears to have involved not only the volcanic edifice, but also a substantial component of a fringing bioclastic shelf, and material locally incorporated from the underlying seafloor. This information allows us to test how first-order landslide morphology (e.g. blocky or elongate lobes) is related to first-order landslide composition. Preliminary analysis suggests that Deposit 1 occurred shortly before a second major landslide on the SW of the island (Deposit 5). It may have initiated English's Crater, but was not associated with a major change in magma composition. An associated turbidite-stack suggests it was emplaced in multiple stages, separated by at least a few hours and thus reducing the tsunami magnitude. The ROV dives show that mega-blocks in detail comprise smaller-scale breccias, which can travel significant distances without complete disintegration. Landslide Deposit 2 was emplaced at ~130ka, and is more voluminous (~8.4km cubed). It had a much more profound influence on the magmatic system, as it was linked to a major explosive mafic eruption and formation of a new volcanic centre (South Soufriere Hills) on the island. Site U1395 confirms a hypothesis based on the site survey seismic data that Deposit 2 includes a substantial component of pre-existing seafloor sediment. However, surprisingly, this pre-existing seafloor sediment in the lower part of Deposit 2 at Site U1395 is completely undeformed and flat lying, suggesting that Site U1395 penetrated a flat lying block. Work to date material from the upper part of U1396, U1395 and U1394 will also be summarised. This work is establishing a chronostratigraphy of major events over the last 1 Ma, with particularly detailed constraints during the last ~250ka. This is helping us to understand whether major landslides are related to cycles of volcanic eruptions.
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IODP Expedition 340 successfully drilled a series of sites offshore Montserrat, Martinique and Dominica in the Lesser Antilles from March to April 2012. These are among the few drill sites gathered around volcanic islands, and the first scientific drilling of large and likely tsunamigenic volcanic island-arc landslide deposits. These cores provide evidence and tests of previous hypotheses for the composition and origin of those deposits. Sites U1394, U1399, and U1400 that penetrated landslide deposits recovered exclusively seafloor sediment, comprising mainly turbidites and hemipelagic deposits, and lacked debris avalanche deposits. This supports the concepts that i/ volcanic debris avalanches tend to stop at the slope break, and ii/ widespread and voluminous failures of preexisting low-gradient seafloor sediment can be triggered by initial emplacement of material from the volcano. Offshore Martinique (U1399 and 1400), the landslide deposits comprised blocks of parallel strata that were tilted or microfaulted, sometimes separated by intervals of homogenized sediment (intense shearing), while Site U1394 offshore Montserrat penetrated a flat-lying block of intact strata. The most likely mechanism for generating these large-scale seafloor sediment failures appears to be propagation of a decollement from proximal areas loaded and incised by a volcanic debris avalanche. These results have implications for the magnitude of tsunami generation. Under some conditions, volcanic island landslide deposits composed of mainly seafloor sediment will tend to form smaller magnitude tsunamis than equivalent volumes of subaerial block-rich mass flows rapidly entering water. Expedition 340 also successfully drilled sites to access the undisturbed record of eruption fallout layers intercalated with marine sediment which provide an outstanding high-resolution data set to analyze eruption and landslides cycles, improve understanding of magmatic evolution as well as offshore sedimentation processes.
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This article considers the significance of a leading marine biodiscovery initiative. In March 2004, Dr. J. Craig Venter announced the official launch of the Sorcerer II Expedition, a scientific expedition of discovery, which would survey marine and terrestrial microbial populations. The Expedition has the potential to uncover tens of thousands of new microbial species and tens of millions of new genes. Venter has disavowed that the Sorcerer II Expedition has any commercial ambitions. However, some have viewed the Sorcerer II Expedition with suspicion. Various civil society groups have accused the Expedition of engaging in 'biopiracy'. This article investigates the Convention on Biological Diversity 1992 and other relevant international treaties, various national and regional regimes to govern access to genetic resources, and benefit-sharing agreements. It considers the intersection of intellectual property law, contract law, environmental law, and international law in this field. This article provides a blueprint for a nationally consistent scheme for access to genetic resources, and a model for future international developments.
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Ei saatavilla
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The RASCALS expedition spent over three weeks at the Summit camp research station near the top of the Greenland Ice Sheet during polar summer 2010. During this time, detailed measurements of the physical and optical properties of Arctic perennial snow were carried out concurrently with snow albedo and reflectance measurements. Favorable weather conditions during the campaign enabled the collection of a large dataset on Arctic snow albedo and associated quantities for use in developing and validating remote sensing algorithms for snow albedo using satellites. This report provides a description of the measurements and conditions during the campaign. RASCALS-retkikunnan tehtävä oli tutkia Grönlannin mannerjäätikön lumen fysikaalisia ja optisia ominaisuuksia sekä Auringon valon vuorovaikutusta lumen kanssa. Retikunta vietti hieman yli kolme viikkoa mannerjäätikön keskellä sijaitsevalla Summit Camp-tutkimusasemalla tehden mittauksia. Sääolot suosivat kampanjaa, jonka seurauksena onnistuttiin keräämään laaja ja monipuolinen tietoaineisto mannerjäätikön lumen pintakerroksesta ja eritoten lumen heijastavuuden (albedon)käyttäytymisestä. Aineisto on hyödyllinen kehitettäessä ja varmennettaessa lumen albedon kaukokartoitusmenetelmiä satelliiteilla.
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Genetic mutations in microcephalinl (MCPH1) cause primary autosomal recessive microcephaly which is characterized by a marked reduction in brain size. MCPH1 encodes a centrosomal protein with three BRCT (BRCA1 C-terminal) domains. Also, it is a key regulator of DNA repair pathway and cell cycle checkpoints. Interestingly, in the past few years, many research studies have explored the role of MCPH1, a neurodevelopmental gene in several cancers and its tumor suppressor functions have been elucidated. Given the diverse new emerging roles, it becomes critical to review and summarize the multiple roles of MCPH1 that is currently lacking in the literature. In this review after systematic analysis of literature, we summarise the multiple functional roles of MCPH1 in centrosomal, DNA repair and apoptotic pathways. Additionally, we discuss the considerable efforts taken to understand the implications of MCPH1 in diseases such as primary microcephaly and its other emerging association with cancer and otitis media. The promising view is that MCPH1 has distinct roles and its clinical associations in various diseases makes it an attractive therapeutic target. (C) 2014 Elsevier GmbH. All rights reserved.
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This report contains inorganic nutrient chemistry, sulfide and oxygen data collected during cruises 2 through 5 of the 1988 Black Sea Oceanographic Expedition aboard the R/V Knorr. Continuous nutrient and sulfide data were obtained in the upper 375 m using a pumped profiling system. Discrete samples were collected from rosette-CTD casts. The corresponding physical oceanographic data have been presented by White et al. (1989). Although all of the data reported has been edited at least twice, errors may remain. We encourage queries and plan to distribute updates on electronic media if there are any non-trivial changes.
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Dr. Charles M. Breder participated on the 1934 expedition of the Atlantis from Woods Hole, Massachusetts to Panama and back and kept a field diary of daily activities. The Atlantis expedition of 1934, led by Prof. A. E. Parr, was a milestone in the history of scientific discovery in the Sargasso Sea and the West Indies. Although naturalists had visited the Sargasso Sea for many years, the Atlantis voyage was the first attempt to investigate in detailed quantitative manner biological problems about this varying, intermittent ‘false’ bottom of living, floating plants and associated fauna. In addition to Dr. Breder, the party also consisted of Dr. Alexander Forbes, Harvard University and Trustee of the Woods Hole Oceanographic Institution (WHOI); T. S. Greenwood, WHOI hydrographer; M. D. Burkenroad, Yale University’s Bingham Laboratory, carcinology and Sargasso epizoa; M. Bishop, Peabody Museum of Natural History, Zoology Dept., collections and preparations and H. Sears, WHOI ichthyologist. The itinerary included the following waypoints: Woods Hole, the Bermudas, Turks Islands, Kingston, Colon, along the Mosquito Bank off of Nicaragua, off the north coast of Jamaica, along the south coast of Cuba, Bartlett Deep, to off the Isle of Pines, through the Yucatan Channel, off Havana, off Key West, to Miami, to New York City, and then the return to Woods Hole. During the expedition, Breder collected rare and little-known flying fish species and developed a method for hatching and growing flying fish larvae. (PDF contains 48 pages)
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ENGLISH: The purpose of this study was to investigate the possibility that certain species of Chaetognatha found in Eastern Tropical Pacific waters can serve as biological indicators of oceanographic features. "Indicator" organisms have been found useful in identifying water types, in tracing the pattern of current systems, and in tracing the origin of moving water masses. To be of use in this type of study, the organisms must be sufficiently abundant to be readily sampled, and easily identified to species; they must also, at least partially, fulfill the additional requisites listed and discussed by Sverdrup, Johnson, and Fleming (1942, pp. 866-867). Among several groups of organisms fulfilling these requirements are the Chaetognatha. Specimens of this group of animals occurred in large numbers in the plankton samples used for this study. The works of Thomson (1947), Fraser (1942), Ritter-Zahony (1911), and Sund (1959) were used for identification. SPANISH: El objetivo de este estudio ha sido el de investigar la posibilidad de utilizar ciertas especies de quetognatos encontrados en el Pacífico Oriental Tropical como indicadoras biológicas de características oceanográficas. Organismos "indicadores" fueron encontrados útiles para la identificación de tipos de agua, el trazado del régimen de los sistemas de corrientes y la determinación del origen de masas de agua en movimiento. Para servir a este tipo de estudios, los organismos deben ser lo suficientemente abundantes como para ser fácilmente muestreados e identificados hasta la especie; también deben satisfacer, por lo menos parcialmente, los requerimientos indicados y discutidos par Sverdrup, Johnson y Fleming (1942, pags. 866-867).
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ENGLISH: EASTROPIC Expedition was a cooperative oceanographic study of the eastern tropical Pacific Ocean conducted during the period 2 October through 16 December 1955. The five participating agencies and the ships they operated were: Scripps Institution of Oceanography (SIO), Spencer F. Baird and Horizon; Pacific Oceanic Fisheries Investigations (POFI) of the U. S. Fish and Wildlife Service, now Honolulu Biological Laboratory (HBL) of the U. S. Bureau of Commercial Fisheries, Hugh M. Smith; California Department of Fish and Game, N. B. Scofield; the Peruvian Navy, Bondu; and the Inter-American Tropical Tuna Commission which operated no vessels but supplied equipment and personnel. In addition to these planned participations in EASTROPIC Expedition, valuable information was provided by CCOFI Cruise 5512 of the California Cooperative Oceanic Fisheries Investigations, conducted during the period 29 November -16 December 1955 with the two vessels Stranger and Black Douglas. While the observational programs of most of the agencies involved, in part, special hydrographic-biological studies of known features and processes in the region (see reports listed under Data Sources) the deployment of ships and therefore of observations was sufficient that EASTROPIC Expedition could be considered a survey of the eastern tropical Pacific. This report is concerned with that aspect of the Expedition and is a presentation in atlas form of most of the hydrographic data collected. For reasons given below, emphasis has been placed on the upper 300 m of the water column. SPANISH: La Expedición EASTROPIC es un estudio oceanográfico cooperativo del Océano Pacífico Oriental Tropical llevado a cabo durante el período del 2 de octubre al 16 de dícíembre de 1955. Las cinco agencias participantes y los barcos operados por ellas son los siguientes: Scrípps Instítutíon of Oceanography (SIO) , Spencer F. Baird y Horizon; Pacific Oceanic Fisheries Investigatíons (PO'FI) del U. S. Fish and Wildlife Service, ahora Honolulu Biological Laboratory (BHL) del U. S. Bureau of Commercial Fisheries, Hugh M. Smith; California Department of Fish and Game, N. B. Scofield; la Marina Peruana, Bondu; y la Comisión Interamericana del Atún Tropical que no dirigió ningún barco pero proporcionó equipo y personal. Además de estas participaciones planeadas en la Expedición EASTROPIC, fué suministrada información de valor por el Crucero CCOFI 5512 del California Cooperative Fisheries Investigatíons, llevado a cabo durante el período del 29 de noviembre al 16 de diciembre de 1955 con los barcos Stranger y Black Douglas. Aunque los programas de observación de la mayoría de las agencias, comprendieron en parte estudios especiales hidrográficos y biológicos de las características y de los procesos conocidos de la región (véase los informes indicados bajo Fuente de Datos), el despliegue de los barcos, y por lo tanto, de las observaciones, fué suficiente para que la Expedición EASTROPIC pudiera ser considerada como una encuesta del Pacífico Oriental Tropical. Este informe se refiere a este aspecto de la Expedición y es una presentación, en forma de un atlas, de la mayoría de los datos hidrográficos recolectados. Por las razones que se dan a continuación, se le dió énfasis a los 300 m., superiores de la columna de agua. (PDF contains 136 pages.)