901 resultados para Blott, Jack
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The structure and properties of the double-helical form of the alternating copolymer poly(dA-dT) are considered. Different lines of evidence are interpreted in terms of a structure in which every second phosphate-diester linkage has a conformation different from that of the normal B form. A rationale for this “alternating-B” structure is given which provides an explanation for the effects of chemical modifications of the T residues on the binding of the poly(dA-dT)· poly(dA-dT) to the lac repressor of Escherichia coli.
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The aim of this master s thesis was to clarify employees views on outsourcing. The main questions of the study were 1) How the employees dealt with the change created by outsourcing and what things they felt important when implementing the change? 2) What kind of organizational questions the employees paid attention to when moving from one organization to another? 3) What kind of management issues the employees brought up in the outsourcing process? and 4) How the employees reflected change while experienced outsourcing? The theoretical foundations of the study were Jack Mezirow s theory of transformational learning and Yrjö Engeström s theory of expansive learning. The management of outsourcing was viewed by John P. Kotter s change management model. Research casted light on transformation and learning on four levels of analysis: on individual, organizational and management levels and on the level of reflection. The target of the study were the outsourced employees, who were moved from a Finnish public corporation to a private ITC organization along with the services they produce. The study material was eleven interviews from the outsourced employees. The study was implemented by fenomenographical theme analysis. The analysis revealed results in all four levels. On the individual level the main results were the importance of systematic and open information, meaning of social and technical integration and the feeling of employee s own control. On the organizational level the move from the public sector to private and all the changes in organizational culture and in fringe benefitswere fundamental. Organizational learning was analyzed with expansive learning theory. Expanding was perceived in four dimensions: temporal dimension, spatial dimension, responsibility-moral dimension and developmental dimension. On the management level the actions of one s closest manager was vital, as was the upper management s clear engagement and a shared view of the necessity of a change. In the data was found employees reflective talking, which was indicating the meaning of the change and which was interpreted from the learning point of view. According to this study, it is possible to identify and analyze reflective talk and that way have information about employees learning in an organizational change. It was prominent to notice how reflection in the process of outsourcing is extremely versatile and extensive.
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Ab initio GW calculations are a standard method for computing the spectroscopic properties of many materials. The most computationally expensive part in conventional implementations of the method is the generation and summation over the large number of empty orbitals required to converge the electron self-energy. We propose a scheme to reduce the summation over empty states by the use of a modified static remainder approximation, which is simple to implement and yields accurate self-energies for both bulk and molecular systems requiring a small fraction of the typical number of empty orbitals.
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First principles calculations were done to evaluate the lattice parameter, cohesive energy and stacking fault energies of ordered gamma' (Ll(2)) precipitates in superalloys as a function of composition. It was found that addition of Ti and Ta lead to an increase in lattice parameter and decrease in cohesive energy, while Ni antisites had the opposite effect. Ta and Ti addition to stoichiometric Ni3Al resulted in an initial increase in the energies of APB((111)), CSF(111), APB((001)) and SISF(111). However, at higher concentrations, the fault energies decreased. Addition of Ni antisites decreased the energy of all four faults monotonically. A model based on nearest neighbor bonding was used for Ni-3(Al, Ta), Ni-3(Al, Ti) and Ni-3(Al, Ni) pseudo-binary systems and extended to pseudo- ternary Ni-3(Al, Ta, Ni) and Ni-3(Al, Ti, Ni) systems. Recipes were developed for predicting lattice parameters, cohesive energies and fault energies in pseudo- ternary systems on the basis of coefficients derived from simpler pseudobinary systems. The model predictions were found to be in good agreement with first principles calculations for lattice parameters, cohesive energies, and energies of APB((111)) and CSF(111).
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The GW approximation to the electron self-energy has become a standard method for ab initio calculation of excited-state properties of condensed-matter systems. In many calculations, the G W self-energy operator, E, is taken to be diagonal in the density functional theory (DFT) Kohn-Sham basis within the G0 W0 scheme. However, there are known situations in which this diagonal Go Wo approximation starting from DFT is inadequate. We present two schemes to resolve such problems. The first, which we called sc-COHSEX-PG W, involves construction of an improved mean field using the static limit of GW, known as COHSEX (Coulomb hole and screened exchange), which is significantly simpler to treat than GW W. In this scheme, frequency-dependent self energy E(N), is constructed and taken to be diagonal in the COHSEX orbitals after the system is solved self-consistently within this formalism. The second method is called off diagonal-COHSEX G W (od-COHSEX-PG W). In this method, one does not self-consistently change the mean-field starting point but diagonalizes the COHSEX Hamiltonian within the Kohn-Sham basis to obtain quasiparticle wave functions and uses the resulting orbitals to construct the G W E in the diagonal form. We apply both methods to a molecular system, silane, and to two bulk systems, Si and Ge under pressure. For silane, both methods give good quasiparticle wave functions and energies. Both methods give good band gaps for bulk silicon and maintain good agreement with experiment. Further, the sc-COHSEX-PGW method solves the qualitatively incorrect DFT mean-field starting point (having a band overlap) in bulk Ge under pressure.
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Precise information on streamflows is of major importance for planning and monitoring of water resources schemes related to hydro power, water supply, irrigation, flood control, and for maintaining ecosystem. Engineers encounter challenges when streamflow data are either unavailable or inadequate at target locations. To address these challenges, there have been efforts to develop methodologies that facilitate prediction of streamflow at ungauged sites. Conventionally, time intensive and data exhaustive rainfall-runoff models are used to arrive at streamflow at ungauged sites. Most recent studies show improved methods based on regionalization using Flow Duration Curves (FDCs). A FDC is a graphical representation of streamflow variability, which is a plot between streamflow values and their corresponding exceedance probabilities that are determined using a plotting position formula. It provides information on the percentage of time any specified magnitude of streamflow is equaled or exceeded. The present study assesses the effectiveness of two methods to predict streamflow at ungauged sites by application to catchments in Mahanadi river basin, India. The methods considered are (i) Regional flow duration curve method, and (ii) Area Ratio method. The first method involves (a) the development of regression relationships between percentile flows and attributes of catchments in the study area, (b) use of the relationships to construct regional FDC for the ungauged site, and (c) use of a spatial interpolation technique to decode information in FDC to construct streamflow time series for the ungauged site. Area ratio method is conventionally used to transfer streamflow related information from gauged sites to ungauged sites. Attributes that have been considered for the analysis include variables representing hydrology, climatology, topography, land-use/land- cover and soil properties corresponding to catchments in the study area. Effectiveness of the presented methods is assessed using jack knife cross-validation. Conclusions based on the study are presented and discussed. (C) 2015 The Authors. Published by Elsevier B.V.
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El presente estudio se desarrolló durante la época de apante (1994-1995) en la zona de Nueva Guinea (Zelaya central) con los objetivos de conocer la problemática agronómica y económica que se presenta en la producción de frijol (Phaseolus vulgaris L.) en el área de estudio, y más específicamente con el propósito de investigar qué factores de la producción no necesariamente técnicos o económicos están limitando el potencial del rendimiento del cultivo. Como criterio principal se consideraron los niveles de tecnología utilizados por el productor en el caso del frijol de tecnología media y baja. Se tomaron como muestra quince productores. De igual forma se recolectó información sobre todos los aspectos involucrados en la producción de frijol, labores requeridas, mano de obra utilizada, costos de insumos y de mano de obra, y al foral se recolectó información sobre la problemática encontrada durante el ciclo de apante. 1994, la producción obtenida y el precio del producto final, a como lo vendió el productor. Los resultados relevantes del estudio muestran que existe poca atención de parte de las instituciones gubernamentales para potenciar el desarrollo agro técnico del cultivo del frijol. Referente a aspectos agronómicos existe gran variación en las densidades de población manejadas por los productores y no existen criterios objetivos para impulsar planes de fertilización. Los productores de frijol de tecnología media obtienen rendimientos aceptables en sus cultivos. A pesar de conocer la problemática del ataque de plagas y enfermedades en la plantación son pocos los productores que realizan un manejo adecuado de las mismas, los criterios de manejo de plagas y enfermedades no están completamente definidos, por lo que es común notar que son pocos los productores que realizan aplicaciones de insecticidas o fungicidas en sus áreas de producción. Hay una completa ausencia de prácticas de fitoprotección específicamente para el manejo de enfermedades ya que ninguno de los productores reportó ataque de estas. Con relación a las plagas se reporta que solo tres productores no realizan esta labor por reportar una baja o poca incidencia de daños provocados por éstos insectos, el resto de productores si realizan prácticas de control en sus plantíos. Casi todos los productores encuestados en sistema de frijol de tecnología baja, logran un margen bastante bajo de ganancia con respecto a los rendimientos obtenidos al levantar sus cosechas.
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Salt-water encroachment is undoubtedly the problem of most concern to users of ground water in Florida. This is a problem in many coastal areas where water levels are lowered excessively by heavy pumping. It is a problem also in some inland areas where the water-bearing formations contain salty water at relatively shallow depths. Among the coastal areas where wells have become contaminated with salt water are Pinellas County and the Miami area of Dade County. Inland areas where wells are likely to become contaminated with salt water include Seminole County and the southwestern part of Volusia County. The purpose of the investigation is to make a detailed study of the geology and ground-water resources of the county with special emphasis on the problems associated with declining water levels and salt-water contamination. This report reviews briefly the progress of the investigation through February 1954. (PDF contains 43 pages.)
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Approximately 768,500 triploid grass carp ( Ctenopharyngodon idella Valenciennes) were stocked into the Santee Cooper reservoirs, South Carolina between 1989 and 1996 to control hydrilla ( Hydrilla verticillata (L.f.) Royle). Hydrilla coverage was reduced from a high of 17,272 ha during 1994 to a few ha by 1998. During 1997, 1998 and 1999, at least 98 triploid grass carp were collected yearly for population monitoring. Estimates of age, growth, and mortality, as well as population models, were used in the study to monitor triploid grass carp and predict population trends. Condition declined from that measured during a previous study in 1994. The annual mortality rate was estimated at 28% in 1997, 32% in 1998 and 39% in 1999; however, only the 1999 mortality rate was significantly different. Few (2 out of 98) of the triploid grass carp collected during 1999 were older than age 9. We expect increased mortality due to an aging population and sparse hydrilla coverage. During 1999, we estimated about 63,000 triploid grass carp system wide and project less than 3,000 fish by 2004, assuming no future stocking. management, population size Ctenopharyngodon idella, Hydrilla
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Foreword [pdf, < 0.1 MB] Acknowledgements PHASE 1 [pdf, 0.2 MB] Summary of the PICES/NPRB Workshop on Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish (July 19–20, 2007, Seattle, U.S.A.) Background Links to Other Programs Workshop Format Session I. Status of climate change scenarios in the PICES region Session II. What are the expected impacts of climate change on regional oceanography and what are some scenarios for these drivers for the next 10 years? Session III. Recruitment forecasting Session IV. What models are out there? How is climate linked to the model? Session V. Assumptions regarding future fishing scenarios and enhancement activities Session VI Where do we go from here? References Appendix 1.1 List of Participants PHASE 2 [pdf, 0.7 MB] Summary of the PICES/NPRB Workshop on Forecasting Climate Impacts on Future Production of Commercially Exploited Fish and Shellfish (October 30, 2007, Victoria, Canada) Background Workshop Agenda Forecast Feasibility Format of Information Modeling Approaches Coupled bio-physical models Stock assessment projection models Comparative approaches Similarities in Data Requests Opportunities for Coordination with Other PICES Groups and International Efforts BACKGROUND REPORTS PREPARED FOR THE PHASE 2 WORKSHOP Northern California Current (U.S.) groundfish production by Melissa Haltuch Changes in sablefish (Anoplopoma fimbria) recruitment in relation to oceanographic conditions by Michael J. Schirripa Northern California Current (British Columbia) Pacific cod (Gadus macrocephalus) production by Caihong Fu and Richard Beamish Northern California Current (British Columbia) sablefish (Anoplopoma fimbria) production by Richard Beamish Northern California Current (British Columbia) pink (Oncorhynchus gorbuscha) and chum (O. keta) salmon production by Richard Beamish Northern California Current (British Columbia) ocean shrimp (Pandalus jordani) production by Caihong Fu Alaska salmon production by Anne Hollowed U.S. walleye pollock (Theragra chalcogramma) production in the eastern Bering Sea and Gulf of Alaska by Kevin Bailey and Anne Hollowed U.S. groundfish production in the eastern Bering Sea by Tom Wilderbuer U.S. crab production in the eastern Bering Sea by Gordon H. Kruse Forecasting Japanese commercially exploited species by Shin-ichi Ito, Kazuaki Tadokoro and Yasuhiro Yamanka Russian fish production in the Japan/East Sea by Yury Zuenko, Vladimir Nuzhdin and Natalia Dolganova Chum salmon (Oncorhynchus keta) production in Korea by Sukyung Kang, Suam Kim and Hyunju Seo Jack mackerel (Trachurus japonicus) production in Korea by Jae Bong Lee and Chang-Ik Zhang Chub mackerel (Scomber japonicus) production in Korea by Jae Bong Lee, Sukyung Kang, Suam Kim, Chang-Ik Zhang and Jin Yeong Kim References Appendix 2.1 List of Participants PHASE 3 [pdf, < 0.1 MB] Summary of the PICES Workshop on Linking Global Climate Model Output to (a) Trends in Commercial Species Productivity and (b) Changes in Broader Biological Communities in the World’s Oceans (May 18, 2008, Gijón, Spain) Appendix 3.1 List of Participants Appendix 3.2 Workshop Agenda (Document contains 101 pages)
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The U.S. Geological Survey was requested in 1967 to locate areas that would most likely yield the greatest quantities of the best quality water to satisfy the projected municipal needs of western Collier County. The investigation included the following phases: (1) evaluation of existing data; (2) determination of the hydrologic and geologic characteristics of the subsurface materials; (3) collection of miscellaneous discharge data in the inland canal complex and interpretation of the data; and (4) determination of the quality of water. (PDF has 40 pages)
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This study was done to determine the amount and kinds of water being produced from the lower Hillsboro Canal Area in Palm Beach and Broward counties. All of the potable ground water being produced from the Biscayne aquifer is developed from the canal through infiltration. Rainfall in the area is the ultimate source for all of the water. Careful control and management will allow the development of large quantities of water from the canal toward Lake Okeechobee, but a fresh water head must be maintained along the contact of fresh water with sea water to prevent salt water intrusion. (PDF contains 51 pages.)
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The 19th Annual Symposium on Sea Turtle Biology and Conservation was the largest to date. The beautiful venue was the South Padre Island Convention Centre on South Padre Island, Texas from March 2-6, 1999. Key features of the 19th were invited talks on the theme The Promise, the Pain, and the Progress of 50 years of Sea Turtle Research and Conservation, a mini-symposium on the Kemp's ridley and an increased emphasis on high quality poster sessions. Hosts for the meeting included Texas A&M University, the Texas Sea Grant College Program, The Gladys Porter Zoo and Sea Turtle, Inc. Co-sponsors included the National Marine Fisheries Service-Southeast Fisheries Science Center, the National Marine Fisheries Service-Protected Resources Branch, Padre Island National Seashore and the U.S. Fish and Wildlife Service. With the assistance of Jack Frazier, we were fortunate to obtain a $30,000 grant from the David and Lucile Packard Foundation. This grant provided travel support to 49 individuals from 24 nations who presented a total of 50 presentations. (PDF contains 309 pages)
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For the first time in its history, the International Symposium on Sea Turtle Biology and Conservation migrated to a site outside of the United States. Thus the Eighteenth edition was hosted by the Mazatlán Research Unit of the Instituto de Ciencias del Mar y Limnología of the Mexican National Autonomous University (UNAM) in Mazatlán, Sinaloa (Mexico) where it was held from 3-7, March, 1998. Above all, our symposium is prominent for its dynamism and enthusiasm in bringing together specialists from the world´s sea turtle populations. In an effort to extend this philosophy, and fully aware of how fast the interest in sea turtles has grown, the organizers paid special attention to bring together as many people as possible. With the tremendous efforts of the Travel Committee and coupled with a special interest by the Latin American region´s devotees, we managed to get 653 participants from 43 countries. The number of presentations increased significantly too, reaching a total of 265 papers, ranging from cutting-edge scientific reports based on highly sophisticated methods, to the experiences and successes of community-based and environmental education programs. A priority given by this symposium was the support and encouragement for the construction of "bridges" across cultural and discipline barriers. We found success in achieving a multinational dialogue among interest groups- scientists, resource managers, decision makers, ngo's, private industry. There was a broad representation of the broad interests that stretch across these sectors, yet everyone was able to listen and offer their own best contribution towards the central theme of the Symposium: the conservation of sea turtles and the diversity of marine and coastal environments in which they develop through their complicated and protracted life cycle. Our multidisciplinary approach is highly important at the present, finding ourselves at a cross roads of significant initiatives in the international arena of environmental law, where the conservation of sea turtles has a key role to play. Many, many people worked hard over the previous 12 months, to make the symposium a success. Our sincerest thanks to all of them: Program committee: Laura Sarti (chair), Ana Barragán, Rod Mast, Heather Kalb, Jim Spotilla, Richard Reina, Sheryan Epperly, Anna Bass, Steve Morreale, Milani Chaloupka, Robert Van Dam, Lew Ehrhart, J. Nichols, David Godfrey, Larry Herbst, René Márquez, Jack Musick, Peter Dutton, Patricia Huerta, Arturo Juárez, Debora Garcia, Carlos Suárez, German Ramírez, Raquel Briseño, Alberto Abreu; Registration and Secretary: Jane Provancha (chair), Lupita Polanco; Informatics: Germán Ramírez, Carlos Suárez; Cover art: Blas Nayar; Designs: Germán Ramírez, Raquel Briseño, Alberto Abreu. Auction: Rod Mast; Workshops and special meetings: Selina Heppell; Student prizes: Anders Rhodin; Resolutions committee: Juan Carlos Cantú; Local organizing committee: Raquel Briseño, Jane Abreu; Posters: Daniel Ríos and Jeffrey Semminoff; Travel committee: Karen Eckert (chair), Marydele Donnelly, Brendan Godley, Annette Broderick, Jack Frazier; Student travel: Francisco Silva and J. Nichols; Vendors: Tom McFarland and J. Nichols; Volunteer coordination: Richard Byles; Latin American Reunión: Angeles Cruz Morelos; Nominations committee: Randall Arauz, Colleen Coogan, Laura Sarti, Donna Shaver, Frank Paladino. Once again, Ed Drane worked his usual magic with the Treasury of the Symposium Significant financial contributions were generously provided by government agencies. SEMARNAP (Mexico´s Ministry of Environment, Natural Resources and Fisheries) through its central office, the Mazatlán Regional Fisheries Research Center (CRIP-Mazatlán) and the National Center for Education and Capacity Building for Sustainable Development (CECADESU) contributed to the logistics and covered the costs of auditoria and audiovisual equipment for the Symposium, teachers and their hotels for the Community Development and Environmental Education workshop in the 5th Latin American Sea Turtle Specialists; DIF (Dept of Family Affairs) provided free accomodation and food for the more than 100 participants in the Latin American Reunion. In this Reunion, the British Council-Mexico sponsored the workshop on the Project Cycle. The National Chamber of the Fisheries Industry (CANAINPES) kindly sponsored the Symposium´s coffee breaks. Personnel from the local Navy (Octave Zona Naval) provided invaluable aid in transport and logistics. The Scientific Coordination Office from UNAM (CICUNAM) and the Latin American Biology Network (RELAB) also provided funding. Our most sincere recognition to all of them. In the name of this Symposium´s compilers, I would like to also express our gratitude to Wayne Witzell, Technical Editor for his guidance and insights and to Jack Frazier for his help in translating and correcting the English of contributions from some non-native English speakers. Many thanks to Angel Fiscal and Tere Martin who helped with the typing in the last, last corrections and editions for these Proceedings. To all, from around the world, who generously helped make the 18th Symposium a huge success, shared their experiences and listened to ours, our deepest gratitude! (PDF contains 316 pages)