WorldWideScience

Sample records for delta electronic resource

  1. Effects of climate change on evapotranspiration over the Okavango Delta water resources

    Science.gov (United States)

    Moses, Oliver; Hambira, Wame L.

    2018-06-01

    In semi-arid developing countries, most poor people depend on contaminated surface or groundwater resources since they do not have access to safe and centrally supplied water. These water resources are threatened by several factors that include high evapotranspiration rates. In the Okavango Delta region in the north-western Botswana, communities facing insufficient centrally supplied water rely mainly on the surface water resources of the Delta. The Delta loses about 98% of its water through evapotranspiration. However, the 2% remaining water rescues the communities facing insufficient water from the main stream water supply. To understand the effects of climate change on evapotranspiration over the Okavango Delta water resources, this study analysed trends in the main climatic parameters needed as input variables in evapotranspiration models. The Mann Kendall test was used in the analysis. Trend analysis is crucial since it reveals the direction of trends in the climatic parameters, which is helpful in determining the effects of climate change on evapotranspiration. The main climatic parameters required as input variables in evapotranspiration models that were of interest in this study were wind speeds, solar radiation and relative humidity. Very little research has been conducted on these climatic parameters in the Okavango Delta region. The conducted trend analysis was more on wind speeds, which had relatively longer data records than the other two climatic parameters of interest. Generally, statistically significant increasing trends have been found, which suggests that climate change is likely to further increase evapotranspiration over the Okavango Delta water resources.

  2. NATURAL RESOURCE ABUNDANCE, EXPLOITATION AND AGITATION FOR RESOURCE CONTROL IN NIGERIA’S NIGER DELTA: A MARXIAN ANALYSIS

    Directory of Open Access Journals (Sweden)

    Ogaboh AGBA

    2014-06-01

    Full Text Available Prolonged agitation for resource control in Nigeria’s Niger Delta has attracted increasing attention of academia and policy makers. Key issues are involved-fiscal federalism principles, resource control agitation strategies/intensities and politico-philosophical bases within constitutional and theoretical frameworks, past and present governments’ efforts aimed at resolving agitations by Niger Delta peoples for resource control have been examined from various traditional disciplinary perspectives in social sciences and humanities. This study explains conflicting postures of resources control, and dynamics of the struggle by applying fragments of the revolutionary Marxist ideology/ frameworks comprising Gramscian, Dialectical Materialism and the Frankfort School’s Critical Social and Neo-Marxist (conflict theoretical perspectives espoused by Lewis Coser and C. Wright Mills. We argue that sections of Nigeria’s laws (the Constitution, and 1978 Land Use Act that vested absolute land ownership/control authority on Nigeria’s Federal Government, among other obnoxious laws that promote marginalization of particular oppressed sections/strata of Nigeria’s population thereby provoking persistent conflicts, such laws are overdue for amendment. We recommend, among others, that: non-exploitative variety of federalism applied in Scandinavia (Norway, Switzerland, etc. should be implemented in Nigeria.

  3. delta-vision

    Data.gov (United States)

    California Natural Resource Agency — Delta Vision is intended to identify a strategy for managing the Sacramento-San Joaquin Delta as a sustainable ecosystem that would continue to support environmental...

  4. Indonesian law and reality in the Delta : a socio-legal inquiry into laws, local bureaucrats and natural resources management in the Mahakam Delta, East Kalimantan

    NARCIS (Netherlands)

    Simarmata, Rikardo

    2012-01-01

    This book provides a socio-legal inquiry into the legal and administrative management of the natural resources of the Mahakam Delta, East Kalimantan, Indonesia. This book argues that due to a combination of complex legal and non-legal factors, laws and regulations on natural resources management of

  5. Direct Detection and Imaging of Low-Energy Electrons with Delta-Doped Charge-Coupled Devices

    Science.gov (United States)

    Nikzad, S.; Yu, Q.; Smith, A. L.; Jones, T. J.; Tombrello, T. A.; Elliott, S. T.

    1998-01-01

    We report the use fo delta-doped charge-coupled devices (CCDs) for direct detection of electrons in the 50-1500 eV energy range. These are the first measurements with a solid state device to detect electrons in this energy range.

  6. Soils, people and policy: land resource management conundrum in the Okavango Delta, Botswana

    Directory of Open Access Journals (Sweden)

    Oluwatoyin Dare Kolawole

    2017-06-01

    Full Text Available The multi-faceted aspects of natural resource governance underscore the complex nature of the subject. The intricacies associated with the skewed power relations between those who allocate these resources (land, in this case and those who access and use them vis à vis environmental conservation make the subject a daunting one. Based on preliminary field observations and farmers’ opinions on soil health conditions in the Okavango Delta, the paper assesses the nutrient status of selected farmers’ fields and how the smallholders and government respond to this peculiar ecological environment. It specifically analyses small farmers’ perceptions on the political ecology of soil management in the area. We used a multi-stage sampling procedure to sample 228 smallholder farmers. The smallholders were interviewed using interview schedules. Key informant interviews were used to collect qualitative data from farmers as well. Thirty-three (33 composite soil samples were collected from 30 farmers’ plots in three farming communities (Makalamabedi, Nokaneng and Mohembo. Laboratory analysis shows that most soils in the wetland and its dryland surroundings are generally acidic, low in essential nutients as well as in cation-exchange-capacity (CEC. However, the results of a one-way analysis of variance (ANOVA conducted shows significant differences in soil nutrient levels in different locations within the Delta. While farming remains an important livelihood of rural communities, policies on natural resource governance particularly along the river channels delimit local farmers’ ability to engage in meaningful soil fertility management. The low CEC of the soils is an indication that holistic cultural practices, which are beyond mere chemical fertilizations are critical and more desirable for improved soil health and sustainable rural livelihoods in the Delta.

  7. Electronic Resource Management and Design

    Science.gov (United States)

    Abrams, Kimberly R.

    2015-01-01

    We have now reached a tipping point at which electronic resources comprise more than half of academic library budgets. Because of the increasing work associated with the ever-increasing number of e-resources, there is a trend to distribute work throughout the library even in the presence of an electronic resources department. In 2013, the author…

  8. CAPITALISATION OF NATURAL RESOURCES FOR TOURISM PURPOSES IN THE DANUBE DELTA

    Directory of Open Access Journals (Sweden)

    IOAN ILDIKO

    2015-06-01

    Full Text Available The Danube Delta outstands by a number of characteristics that outline its uniquiness at national, regional and world level, pattern that is recognized by its multiple natural reserve status (biosphere reserve, Ramsar site, UNESCO natural heritage site, Natura 2000 site. Despite major technical works that were prior performed for the development of transportation, agriculture, and mining in the Danube Delta, the territory still preserves untamed ecosystems that create breath-taking landscapes and allow a powerful transformative experience of wilderness with major sustainability education potential for its visitors. Meanwhile, traditional economic activities are declining and local communities are experiencing mainly the drawbacks of remoteness instead of harnessing the valuable opportunities born within the current economic trends that emphasize the need to capture the positive externalities of well-preserved natural ecosystems. The Danube Delta is already a well-known tourism destination, but this status still fails to improve local wellbeing. Thus the richness of natural resources is conflicting with the wellbeing of communities with most of the people living at the edge of poverty. This “resource curse” like situation is the main reason that motivates our study that envisages outlining how tourism development and management could create the economic capacity that delivers prosperity for local communities without jeopardising the conservation goals of the natural reserve. In this respect we revisited a number of characteristics of tourism potential, tourism indicators, patterns of tourism products, and the current tourism management. This analysis revealed that there are a number of positive trends, but also the need to strengthen the measures that support high value added tourism products that allow avoiding the threat of numerous visitors and the development of mass tourism infrastructure. The relevance of these conclusions is limited by

  9. Deformation characteristics of {delta} phase in the delta-processed Inconel 718 alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, H.Y., E-mail: haiyanzhang@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Zhang, S.H., E-mail: shzhang@imr.ac.cn [Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Cheng, M. [Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016 (China); Li, Z.X. [Beijing Institute of Aeronautica1 Materials, Beijing 100095 (China)

    2010-01-15

    The hot working characteristics of {delta} phase in the delta-processed Inconel 718 alloy during isothermal compression deformation at temperature of 950 deg. C and strain rate of 0.005 s{sup -1}, were studied by using optical microscope, scanning electron microscope and quantitative X-ray diffraction technique. The results showed that the dissolution of plate-like {delta} phase and the precipitation of spherical {delta} phase particles coexisted during the deformation, and the content of {delta} phase decreased from 7.05 wt.% to 5.14 wt.%. As a result of deformation breakage and dissolution breakage, the plate-like {delta} phase was spheroidized and transferred to spherical {delta} phase particles. In the center with largest strain, the plate-like {delta} phase disappeared and spherical {delta} phase appeared in the interior of grains and grain boundaries.

  10. Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

    Energy Technology Data Exchange (ETDEWEB)

    Dormeval, M

    2001-09-01

    The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

  11. Spin-polarized electron tunneling across a Si delta-doped GaMnAs/n-GaAs interface

    DEFF Research Database (Denmark)

    Andresen, S.E.; Sørensen, B.S.; Lindelof, P.E.

    2003-01-01

    Spin-polarized electron coupling across a Si delta-doped GaMnAs/n-GaAs interface was investigated. The injection of spin-polarized electrons was detected as circular polarized emission from a GaInAs/GaAs quantum well light emitting diode. The angular momentum selection rules were simplified...

  12. Electronic structure of Pu-Ce(-Ga) and Pu-Am(-Ga) alloys, stabilized in the {delta} phase; Structure electronique d'alliages Pu-Ce(-Ga) et Pu-Am(-Ga) stabilises en phase {delta}

    Energy Technology Data Exchange (ETDEWEB)

    Dormeval, M

    2001-09-01

    The behaviour of {delta}-plutonium, stable between 319 and 451 deg C, exhibits numerous singularities which are still a mystery for both physicists and metallurgists. This is due to its complex electronic structure, and in particular to the 5f electrons, which are at the edge between localization and delocalization. The stability domain of the {delta} phase can be extended down to room temperature by alloying with so called 'deltagen atoms' such as gallium (Ga), aluminum (A1), cerium (Ce) or americium (Am). The present work deals, one the one hand, with the influence of cerium and americium solutes regarding the localization of the 5f electrons of {delta}-plutonium, in binary Pu-Ce and Pu-Am alloys. On the other hand, the effect of two different deltagen solutes, simultaneously present, on the stability of the {delta} phase has been studied in ternary Pu-Am-Ga and Pu-Ce-Ga alloys. The electronic structure being strongly related to the crystalline organization, characterization methods such as X-Ray diffraction and EXAFS measurements were used together with electrical resistivity and magnetic susceptibility experiments. These showed that the roles of cerium and americium, supposed to be similar at the beginning of this investigation, are actually very different. Moreover, the additive effect of cerium and gallium, and, americium and gallium, has been demonstrated. Studying plutonium alloys, which are radioactive, also means following their evolution in time. The characteristics of the alloys have then been followed which allowed to detect, in Pu-Ce(-Ga) alloys, a destabilization of the {delta} phase and, to observe, in Pu-Am(-Ga) alloys, the influence of self-irradiation defects on the magnetic response. (author)

  13. Fragmentation of delta-diketones by electron impact. Olefin elimination and formation of an enol acetate ion

    International Nuclear Information System (INIS)

    Morizur, J.P.; Mercier, J.; Casals, P.F.

    1985-01-01

    Under electron impact delta-diketones lose an olefin. The mechanism and structure of the resulting ion have been established by several techniques: substitution, Mike and Cid spectra and thermochemical data [fr

  14. Delta electron spectroscopy for the study of the inner-shell excitation in heavy ion collisions

    International Nuclear Information System (INIS)

    Trollmann, G.

    1981-01-01

    In this thesis energy and angular differential cross sections of delta electrons from ion-atom collisions are measured and compared with different perturbation theories. Shell specific cross sections were obtained from electron-X-ray coincidences. Contradicting theoretical statements concerning the angular distribution of the electrons can be experimentally clarified, other predictions are verified. Starting from fast, strongly asymmetric collisions until to slow, more symmetric collisions the question of the disturbance of the stationary target state by the projectile and the formation of intermediate molecular state is studied. With the results of the measurement of the delta electrons it can be contributed to the clarification of the question for the physical origin of the continuous X-radiation in the energy range beyond the K-line of the heavier collision partner. It is shown that the secondary electron bremsstrahlung discussed as radiation source besides the molecular orbital (MO) radiation is in its intensity about more than one order of magnitude weaker than the measured X-radiation and is therefore excluded as dominant radiation. In the framework of this work an apparature was developed, which allows the electron spectroscopy in the energy range between 10 keV and 150 keV and the angular range between 5 degrees and 180 degrees for the absolute determination of double differential cross sections. (orig./HSI) [de

  15. Electronic Structure of TlBa2CaCu2O(7-Delta)

    Science.gov (United States)

    Vasquez, R. P.; Novikov, D. L.; Freeman, A. J.; Siegal, M. P.

    1997-01-01

    The core levels of TlBa2CaCu2O(7-delta) (Tl-1212) epitaxial films have been measured with X-ray photoelectron spectroscopy (XPS). The valence electronic structure has been determined using the full-potential linear muffin-tin-orbital band-structure method and measured with XPS. The calculations show that a van Hove singularity (VHS) lies above the Fermi level (E(sub F)) for the stoichiometric compound (delta = 0.5), while for 50% oxygen vacancies in the Tl-O layer (delta = 0.5) E(sub F) is in close proximity to the VHS. Samples annealed in nitrogen (to reduce the hole overdoping by the removal of oxygen) exhibit higher core-level binding energies and a higher T(sub c), consistent with a shift of E(sub F) closer to the VHS. Comparisons are made to the core levels and valence bands of Tl2Ba2CaCu2O(8 + delta)(Tl-2212) and HgBa2CaCu2O)6 + delta) (Hg- 1212). The similarity of the Cu 2p(sub 3/2) spectra for Tl-1212 and Tl-2212 indicates that the number of Tl-O layers has little effect on the Cu-O bonding. However, the Tl-1212 and Hg-1212 Cu 2p(sub 3/2) signals exhibit differences which suggest that the replacement of T(sup 3+) with Hg(sup 2+) results in a decrease in the O 2p right arrow Cu 3d charge-transfer energy and differences in the probabilities of planar vs apical oxygen charge transfer and/or Zhang-Rice singlet-state formation. Differences between the Tl-1212 and the Tl-2212 and Hg-1212 measured valence bands are consistent with the calculated Cu 3d and (Tl,Hg) 6s/5d partial densities of states.

  16. Electronic Structure of TIBa(sub 2)CaCu(sub 2)O(sub 7-delta)

    Science.gov (United States)

    Vasquez, R. P.; Novikov, D. L.; Freeman, A. J.; Siegal, M. P.

    1996-01-01

    The core levels of TIBa(sub 2)CaCu(sub 2)O(sub 7-delta) epitaxial films have been measured with x-ray photoelectron spectroscopy (XPS). The valence electronic structure has been determined using the full-potential linear muffin tin orbital band structure method and measured with XPS.

  17. Electronic Resource Management Systems

    Directory of Open Access Journals (Sweden)

    Mark Ellingsen

    2004-10-01

    Full Text Available Computer applications which deal with electronic resource management (ERM are quite a recent development. They have grown out of the need to manage the burgeoning number of electronic resources particularly electronic journals. Typically, in the early years of e-journal acquisition, library staff provided an easy means of accessing these journals by providing an alphabetical list on a web page. Some went as far as categorising the e-journals by subject and then grouping the journals either on a single web page or by using multiple pages. It didn't take long before it was recognised that it would be more efficient to dynamically generate the pages from a database rather than to continually edit the pages manually. Of course, once the descriptive metadata for an electronic journal was held within a database the next logical step was to provide administrative forms whereby that metadata could be manipulated. This in turn led to demands for incorporating more information and more functionality into the developing application.

  18. Assessing Niger-Delta Wetland Resources: A Case-Study of Mangrove Ecosystem

    Science.gov (United States)

    Anwan, R. H.; Ndimele, P. E.; Whenu, O. O.; Anetekhai, M. A.; Essien-Ibok, M. A.; Erondu, E. S.

    2016-02-01

    The Niger Delta is located in the Atlantic coast of Southern Nigeria and is the world's second largest delta with a coastline of about 450km. The Niger Delta region occupies a surface area of about 112,110km2, representing about 12% of Nigeria's total surface area. The Delta's environment can be broken down into four ecological zones: coastal barrier islands, mangrove swamp forests, freshwater swamps, and lowland rainforests. The mangrove swamps of Niger Delta, which is the largest delta in Africa constitute the dominant wetland ecosystem in the Niger Delta region and covers an area of about 1,900km2. Mangroves constitute important nurseries for fishes, crustaceans, sponges, algae and other invertebrates, and also acts as a sink, retaining pollutants from contaminated tidal water. The Niger Delta mangrove together with the creeks and rivers are a major source of food and livelihood for about 30 million people, which represents more than 17% of Nigeria's population. Other ecosystem services provided by this unique environment are flood control, ground water re-fill, reservoir of biodiversity, fuel wood, cultural values etc. This ecosystem also plays important role in climate change mitigation because of its high blue carbon sequestration potential. This is particularly important because of continuous gas flaring in Niger Delta from petroleum operations, which releases carbon dioxide among other gases into the atmosphere. This wetland is potentially a good site for ecotourism and also qualifies to be a world heritage site and Ramsar site if proper steps are taken. The benefits derivable from this fragile ecosystem are under severe threat by anthropogenic stressors. These include the installation of pipelines and seismic exploration by oil companies, crude oil pollution, deforestation, urbanization etc. This paper discusses the extent of depletion and loss of mangrove ecosystem in the Niger Delta region and the value of its goods and services.

  19. Electronic Resources Management Project Presentation 2012

    KAUST Repository

    Ramli, Rindra M.

    2012-11-05

    This presentation describes the electronic resources management project undertaken by the KAUST library. The objectives of this project is to migrate information from MS Sharepoint to Millennium ERM module. One of the advantages of this migration is to consolidate all electronic resources into a single and centralized location. This would allow for better information sharing among library staff.

  20. Users' Satisfaction with Library Information Resources and Services: A Case Study College of Health Sciences Library Niger Delta University, Amassoma, Nigeria

    Science.gov (United States)

    Tiemo, Pereware Aghwotu; Ateboh, Benedict Alaowei

    2016-01-01

    This study investigated users' satisfaction with library information resources and services at the College of Health Sciences (CHS) library Niger Delta University, Nigeria. The objective was to determine the level of users satisfaction with library information resources and services. 2 (two) research questions were formulated to guide the study.…

  1. Delta Vegetation and Land Use [ds292

    Data.gov (United States)

    California Natural Resource Agency — Vegetation and land use are mapped for the approximately 725,000 acres constituting the Legal Delta portion of the Sacramento and San Joaquin River Delta area....

  2. Connectivity in river deltas

    Science.gov (United States)

    Passalacqua, P.; Hiatt, M. R.; Sendrowski, A.

    2016-12-01

    Deltas host approximately half a billion people and are rich in ecosystem diversity and economic resources. However, human-induced activities and climatic shifts are significantly impacting deltas around the world; anthropogenic disturbance, natural subsidence, and eustatic sea-level rise are major causes of threat to deltas and in many cases have compromised their safety and sustainability, putting at risk the people that live on them. In this presentation, I will introduce a framework called Delta Connectome for studying connectivity in river deltas based on different representations of a delta as a network. Here connectivity indicates both physical connectivity (how different portions of the system interact with each other) as well as conceptual (pathways of process coupling). I will explore several network representations and show how quantifying connectivity can advance our understanding of system functioning and can be used to inform coastal management and restoration. From connectivity considerations, the delta emerges as a leaky network that evolves over time and is characterized by continuous exchanges of fluxes of matter, energy, and information. I will discuss the implications of connectivity on delta functioning, land growth, and potential for nutrient removal.

  3. PRINCIPLES OF CONTENT FORMATION EDUCATIONAL ELECTRONIC RESOURCE

    Directory of Open Access Journals (Sweden)

    О Ю Заславская

    2017-12-01

    Full Text Available The article considers modern possibilities of information and communication technologies for the design of electronic educational resources. The conceptual basis of the open educational multimedia system is based on the modular architecture of the electronic educational resource. The content of the electronic training module can be implemented in several versions of the modules: obtaining information, practical exercises, control. The regularities in the teaching process in modern pedagogical theory are considered: general and specific, and the principles for the formation of the content of instruction at different levels are defined, based on the formulated regularities. On the basis of the analysis, the principles of the formation of the electronic educational resource are determined, taking into account the general and didactic patterns of teaching.As principles of the formation of educational material for obtaining information for the electronic educational resource, the article considers: the principle of methodological orientation, the principle of general scientific orientation, the principle of systemic nature, the principle of fundamentalization, the principle of accounting intersubject communications, the principle of minimization. The principles of the formation of the electronic training module of practical studies in the article include: the principle of systematic and dose based consistency, the principle of rational use of study time, the principle of accessibility. The principles of the formation of the module for monitoring the electronic educational resource can be: the principle of the operationalization of goals, the principle of unified identification diagnosis.

  4. Prospects for Measuring $\\Delta$G from Jets at HERA with Polarized Protons and Electrons

    CERN Document Server

    De Roeck, A.; Kunne, F.; Maul, M.; Schafer, A.; Wu, C.Y.; Mirkes, E.; Radel, G.

    1996-01-01

    The measurement of the polarized gluon distribution function Delta G(x) from photon-gluon fusion processes in electron-proton deep inelastic scattering producing two jets has been investigated. The study is based on the MEPJET and PEPSI simulation programs. The size of the expected spin asymmetry and corresponding statistical uncertainties for a possible measurement with polarized beams of electrons and protons at HERA have been estimated. The results show that the asymmetry can reach a few percent, and is not washed out by hadronization and higher order processes.

  5. Implementing CORAL: An Electronic Resource Management System

    Science.gov (United States)

    Whitfield, Sharon

    2011-01-01

    A 2010 electronic resource management survey conducted by Maria Collins of North Carolina State University and Jill E. Grogg of University of Alabama Libraries found that the top six electronic resources management priorities included workflow management, communications management, license management, statistics management, administrative…

  6. Tidal controls on river delta morphology

    NARCIS (Netherlands)

    Hoitink, A.J.F.; Wang, Z.B.; Vermeulen, B.; Huismans, Y.; Kästner, K.

    2017-01-01

    River delta degradation has been caused by extraction of natural resources, sediment retention by reservoirs, and sea-level rise. Despite global concerns about these issues, human activity in the world's largest deltas intensifies. Harbour development, construction of flood defences, sand mining and

  7. Tidal controls on river delta morphology

    NARCIS (Netherlands)

    Hoitink, A.J.F.; Wang, Zhengbing; Vermeulen, B.; Huismans, Y; Kästner, K

    River delta degradation has been caused by extraction of natural resources, sediment retention by reservoirs, and sea-level rise. Despite global concerns about these issues, human activity in the world’s largest deltas intensifies. Harbour development, construction of flood defences, sand mining and

  8. Managing electronic resources a LITA guide

    CERN Document Server

    Weir, Ryan O

    2012-01-01

    Informative, useful, current, Managing Electronic Resources: A LITA Guide shows how to successfully manage time, resources, and relationships with vendors and staff to ensure personal, professional, and institutional success.

  9. The design of a DataBase for Natural Resources in Danube Delta Biosphere Reserve DDBR

    Directory of Open Access Journals (Sweden)

    GRIGORAS Ion

    2016-12-01

    Full Text Available Efficient use of natural resources especially in Natura 2000 sites is an essential component of Europe 2020 strategy. The use of web database is absolutely necessary for a good resource management and it will provide a good communication channel for the main stakeholders: protected area manager, scientists, resources evaluators and local community. Access to information from database is allowed according with the user competence. General information on natural resources uses in Danube Delta Biosphere Reserve (D.D.B.R. will be freely available. Different degree of information, especially regarding editing data will be applied for the main actors involved in use of natural resources. Evaluators that are mainly scientists with good biodiversity background, protected area staff that applies the regulation regarding natural resources in relation with ecological conditions, private companies or persons interested in harvesting natural resources. The user interface is realized by using OpenSource products. The web interface for tabular data was build using ExtJs Javascrip library. The web map user interface was build using Openlayers, GeoExt, and Ext. For database SQL server we chose PostgresSQL and GeoServer for maps server

  10. Telematic Infrastructures for Flexible and Distance Learning "Electronic Universities." A Report from DELTA Workshops on Telematic Networks for Distance Education and Training "Electronic Universities" and on Learning Technology (October 1990, November 1990).

    Science.gov (United States)

    Moller, Morten, Ed.; Shaughnessy, Haydn, Ed.

    This report is based on contributions to two workshops arranged jointly by Task Force Human Resources and the DELTA (Developing European Learning through Technological Advance) Unit. The purpose of collecting these papers was to provide an overview of the implications of the DELTA Exploratory Action outcomes for future research. After the preface…

  11. Casscf/ci Calculations for First Row Transition Metal Hydrides - the TIH(4-PHI), VH(5-DELTA), CRH(6-SIGMA-PLUS), MNH(7-SIGMA-PLUS), FEH(4,6-DELTA) and NIH(2-DELTA) States

    Science.gov (United States)

    Walch, S. P.; Bauschlicher, C. W., Jr.

    1983-04-01

    Calculations are performed for the predicted ground states of TiH(4-phi), VH(5-delta), CrH(6-sigma-plus), MnH(7-sigma-plus), Fett(4,6-delta) and NiH(2-delta). For FeH both the 6-delta and 4-delta states are studied, since both are likely candidates for the ground state. The ground state symmetries are predicted based on a combination of atomic coupling arguments and coupling of 4s(2)3d(n) and 4s(1)3d(n+1) terms in the molecular system. Electron correlation is included by a CASSCF/CI (SD) treatment. The CASSCF includes near-degeneracy effects, while correlation of the 3d electrons in included at the CI level.

  12. Land Resources Evaluation Of The Paleodarainage Delta In Western Desert Of Egypt Using Remote Sensing Data

    International Nuclear Information System (INIS)

    Afify, A.A.

    2009-01-01

    The study area was selected to represent the sediments of paleodrainage delta in the Western Desert of Egypt, covering about 15615653 feddans (6561199 hectares). The data of Landsat Enhanced Thematic Mapper (ETM) 2002 were used for delineating the physiographic units to be a base for the soil taxonomic units (all are hyperthermic). These taxonomic units were potentially evaluated for barley and wheat (grain crops), alfalfa (fodder crop), maize, sun flower and olives (oil seed crops). The illustrated flow of the paleodrainage delta starts from the south as undulating delta apex, which most probably was deposited by the paleodrainage from Eastern Desert through the different rock structures. This apex includes soils of Calcic Petrogypsids loamy skeletal, gypsic; Typic Clacigypsids, loamy skeletal, gypsic and Typic Calcigypsids, sandy skeletal, mixed. The unit is profitable for drip irrigated olives as moderately to marginally suitable and for quarrying Oligocene gravel. Gently undulating inter delta includes sediments that was most probably received by reworking and out washing the slopes of delta apex in relatively more recent fluvial eras. The soils are Typic Calcigypsids, fine loamy, mixed; Typic Calcigypsids, loamy skeletal, mixed and Typic Calcigypsids, sandy, mixed. This unit is profitable for drip irrigated olives as highly suitable and sprinkly irrigated alfalfa, maize and sun flower as marginally suitable. Gently undulating to almost flat inter delta is most probably received its sediments from the southern physiographic units by the paleodrainage erosion. The soils are Leptic Haplogypsids, fine loamy, mixed and Leptic Haplogypsid, sandy, mixed. This unit is profitable for drip irrigated olives as moderately suitable. In the middle front of this unit, a township is proposed to be constructed A I Qattara Town . Flat depressed pro delta includes interfered sediments of different paleodrainage eras being received medium soil matrix over relatively old sediments

  13. Electronic and physico-chemical properties of nanometric boron delta-doped diamond structures

    International Nuclear Information System (INIS)

    Chicot, G.; Fiori, A.; Tran Thi, T. N.; Bousquet, J.; Delahaye, J.; Grenet, T.; Eon, D.; Omnès, F.; Bustarret, E.; Volpe, P. N.; Tranchant, N.; Mer-Calfati, C.; Arnault, J. C.; Gerbedoen, J. C.; Soltani, A.; De Jaeger, J. C.; Alegre, M. P.; Piñero, J. C.; Araújo, D.; Jomard, F.

    2014-01-01

    Heavily boron doped diamond epilayers with thicknesses ranging from 40 to less than 2 nm and buried between nominally undoped thicker layers have been grown in two different reactors. Two types of [100]-oriented single crystal diamond substrates were used after being characterized by X-ray white beam topography. The chemical composition and thickness of these so-called delta-doped structures have been studied by secondary ion mass spectrometry, transmission electron microscopy, and spectroscopic ellipsometry. Temperature-dependent Hall effect and four probe resistivity measurements have been performed on mesa-patterned Hall bars. The temperature dependence of the hole sheet carrier density and mobility has been investigated over a broad temperature range (6 K  2 /Vs, independently of the layer thickness and the substrate type. Comparison with previously published data and theoretical calculations showed that scattering by ionized impurities explained only partially this low common value. None of the delta-layers showed any sign of confinement-induced mobility enhancement, even for thicknesses lower than 2 nm

  14. Floating City IJmeer : Accelerator for Delta Technology

    NARCIS (Netherlands)

    De Graaf, R.; Fremouw, M.; Van Bueren, B.; Czapiewska, K.; Kuijper, M.

    2006-01-01

    Climate change, sea level rise, population growth and ongoing urbanization result in higher vulnerability of the Rhine delta because it will result in increased flooding frequency, increasing investments and increased use of water, energy and other resources. The Rhine Delta also faces strong

  15. The vacancy order-disorder transition in Ba2YCu3Osub(7-delta) observed by means of electron diffraction and electron microscopy

    International Nuclear Information System (INIS)

    Tendeloo, G. Van; Amelinckx, S.; Zandbergen, H.W.

    1987-01-01

    It is shown by means of electron microscopy and electron diffraction that the ''structural'' vacancies in Ba 2 YCu 3 Osub(7-delta) undergo an order-disorder transformation accompanied by a change in symmetry from orthorhombic to tetragonal. A superstructure due to the ordering of vacancies was found in certain crystal parts; it leads to doubling of the asub(0) parameter. It is shown that the ordering of the vacancies is important for the superconducting behaviour. In order to obtain a high Tsub(c) superconductor the final heat treatment is crucial. (author)

  16. Electron beam asymmetry measurements from exclusive pi0 electroproduction in the Delta(1232) resonance region

    Energy Technology Data Exchange (ETDEWEB)

    K. Joo

    2003-05-01

    The polarized longitudinal-transverse structure function sigma_LT'in the p(e,e'p)pi^0 reaction has been measured for the first time in the Delta(1232) resonance region for invariant mass W = 1.1 - 1.3 GeV and at four-momentum transfer Q^2 = 0.40 and 0.65 GeV^2. Data were taken at the Thomas Jefferson National Accelerator Facility with the CEBAF Large Acceptance Spectrometer (CLAS) using longitudinally polarized electrons at an energy of 1.515 GeV. This newly measured sigma_LT' provides new and unique information on the interference between resonant and non-resonant amplitudes in the Delta(1232) resonance region. The comparison to recent phenomenological calculations shows sensitivity to the description of non-resonant amplitudes and higher resonances.

  17. Gender Analysis Of Electronic Information Resource Use: The Case ...

    African Journals Online (AJOL)

    Based on the findings the study concluded that access and use of electronic information resources creates a “social digital divide” along gender lines. The study ... Finally, the library needs to change its marketing strategies on the availability of electronic information resources to increase awareness of these resources.

  18. Users satisfaction with electronic information resources and services ...

    African Journals Online (AJOL)

    This study investigated users satisfaction on the use of electronic information resources and services in MTN Net libraries in ABU & UNIBEN. Two objectives and one null hypotheses were formulated and tested with respect to the users' satisfaction on electronic information resources and services in MTN Net libraries in ...

  19. Many-electron effect in the Si K-LL resonant Auger-electron spectroscopy spectra of the Si delta layer in GaAs

    International Nuclear Information System (INIS)

    Ohno, Masahide

    2006-01-01

    The Si K-LL resonant Auger-electron spectroscopy (RAES) spectra of silicon delta dopped layers in GaAs with very thin capping layers show both normal Auger decay and resonant Auger decay, when the core-level electron is excited to the conduction band. The resonant Auger peak kinetic energy (KE) shows no dispersion with photon energy, except when excited by the highest energy photons [M.D. Jackson, J.M.C. Thornton, D. Lewis, A. Robinson, M. Fahy, A. Aviary, P. Weightman, Phys. Rev. B71 (2005) 075313]. The RAES spectra are analyzed using a many-body theory. The presence of resonant Auger decay and no dispersion of resonant Auger peak KE with photon energy is explained in terms of the relaxation of a metastable excited core-hole state to a stable one on the time scale of core-hole decay. The excited electron in the conduction band either delocalizes rapidly leaving the ionized Si to decay by a normal Auger decay or drops to a state localized in the Si delta layer before the core-hole decays so that the RAES spectrum has both normal Auger decay and resonant Auger decay. As a result of the relaxation, the resonant Auger peak KE does not show any dispersion with photon energy. The variations with photon energy of the normal or resonant Auger peak intensity, KE, and width are explained in a consistent manner by a many-body theory

  20. Legal Delta Boundary, 2001, DWR [ds586

    Data.gov (United States)

    California Natural Resource Agency — The original topographic maps containing the drawn delta border were scanned from the Department of Water Resources. Images were registered to 1:24,000 USGS DRG's in...

  1. Adaptive Management Methods to Protect the California Sacramento-San Joaquin Delta Water Resource

    Science.gov (United States)

    Bubenheim, David

    2016-01-01

    The California Sacramento-San Joaquin River Delta is the hub for California's water supply, conveying water from Northern to Southern California agriculture and communities while supporting important ecosystem services, agriculture, and communities in the Delta. Changes in climate, long-term drought, water quality changes, and expansion of invasive aquatic plants threatens ecosystems, impedes ecosystem restoration, and is economically, environmentally, and sociologically detrimental to the San Francisco Bay/California Delta complex. NASA Ames Research Center and the USDA-ARS partnered with the State of California and local governments to develop science-based, adaptive-management strategies for the Sacramento-San Joaquin Delta. The project combines science, operations, and economics related to integrated management scenarios for aquatic weeds to help land and waterway managers make science-informed decisions regarding management and outcomes. The team provides a comprehensive understanding of agricultural and urban land use in the Delta and the major water sheds (San Joaquin/Sacramento) supplying the Delta and interaction with drought and climate impacts on the environment, water quality, and weed growth. The team recommends conservation and modified land-use practices and aids local Delta stakeholders in developing management strategies. New remote sensing tools have been developed to enhance ability to assess conditions, inform decision support tools, and monitor management practices. Science gaps in understanding how native and invasive plants respond to altered environmental conditions are being filled and provide critical biological response parameters for Delta-SWAT simulation modeling. Operational agencies such as the California Department of Boating and Waterways provide testing and act as initial adopter of decision support tools. Methods developed by the project can become routine land and water management tools in complex river delta systems.

  2. Organizational matters of competition in electronic educational resources

    Directory of Open Access Journals (Sweden)

    Ирина Карловна Войтович

    2015-12-01

    Full Text Available The article examines the experience of the Udmurt State University in conducting competitions of educational publications and electronic resources. The purpose of such competitions is to provide methodological support to educational process. The main focus is on competition of electronic educational resources. The technology of such contests is discussed through detailed analysis of the main stages of the contest. It is noted that the main task of the preparatory stage of the competition is related to the development of regulations on competition and the definition of criteria for selection of the submitted works. The paper also proposes a system of evaluation criteria of electronic educational resources developed by members of the contest organizing committee and jury members. The article emphasizes the importance of not only the preparatory stages of the competition, but also measures for its completion, aimed at training teachers create quality e-learning resources.

  3. Adaptive Management Using Remote Sensing and Ecosystem Modeling in Response to Climate Variability and Invasive Aquatic Plants for the California Sacramento-San Joaquin Delta Water Resource

    Science.gov (United States)

    Bubenheim, David; Potter, Christopher; Zhang, Minghua; Madsen, John

    2017-01-01

    The California Sacramento-San Joaquin River Delta is the hub for California's water supply and supports important ecosystem services, agriculture, and communities in Northern to Southern California. Expansion of invasive aquatic plants in the Delta coupled with impacts of changing climate and long-term drought is detrimental to the San Francisco Bay/California Delta complex. NASA Ames Research Center and the USDA-ARS partnered with the State of California to develop science-based, adaptive-management strategies for invasive aquatic plant in the Sacramento-San Joaquin Delta. Specific mapping tools developed utilizing satellite and airborne platforms provide regular assessments of population dynamics on a landscape scale and support both strategic planning and operational decision making for resource managers. San Joaquin and Sacramento River watersheds water quality input to the Delta is modeled using the Soil-Water Assessment Tool (SWAT) and a modified SWAT tool has been customized to account for unique landscape and management of agricultural water supply and drainage within the Delta. Environmental response models for growth of invasive aquatic weeds are being parameterized and coupled with spatial distribution/biomass density mapping and water quality to study ecosystem response to climate and aquatic plant management practices. On the water validation and operational utilization of these tools by management agencies and how they are improving decision making, management effectiveness and efficiency will be discussed. The project combines science, operations, and economics related to integrated management scenarios for aquatic weeds to help land and water resource managers make science-informed decisions regarding management and outcomes.

  4. Adaptive Management Using Remote Sensing and Ecosystem Modeling in Response to Climate Variability and Invasive Aquatic Plants for the California Sacramento-San Joaquin Delta Water Resource

    Science.gov (United States)

    Bubenheim, D.; Potter, C. S.; Zhang, M.; Madsen, J.

    2017-12-01

    The California Sacramento-San Joaquin River Delta is the hub for California's water supply and supports important ecosystem services, agriculture, and communities in Northern and Southern California. Expansion of invasive aquatic plants in the Delta coupled with impacts of changing climate and long-term drought is detrimental to the San Francisco Bay/California Delta complex. NASA Ames Research Center and the USDA-ARS partnered with the State of California to develop science-based, adaptive-management strategies for invasive aquatic plant management in the California Sacramento-San Joaquin Delta. Specific mapping tools developed utilizing satellite and airborne platforms provide regular assessments of population dynamics on a landscape scale and support both strategic planning and operational decision making for resource managers. San Joaquin and Sacramento River watersheds water quality input to the Delta is modeled using the Soil-Water Assessment Tool (SWAT) and a modified SWAT tool has been customized to account for unique landscape and management of agricultural water supply and drainage within the Delta. Environmental response models for growth of invasive aquatic weeds are being parameterized and coupled with spatial distribution/biomass density mapping and water quality to study ecosystem response to climate and aquatic plant management practices. On the water validation and operational utilization of these tools by management agencies and how they improve decision making, management effectiveness and efficiency will be discussed. The project combines science, operations, and economics related to integrated management scenarios for aquatic weeds to help land and water resource managers make science-informed decisions regarding management and outcomes.

  5. Options for integrated resource management in the Mackenzie Delta-Beaufort Sea region

    International Nuclear Information System (INIS)

    Green, J.E.

    1991-02-01

    Examples of consultative activities and environmental protection measures are reviewed which have been employed in the Mackenzie Delta/Beaufort Sea region by one or more petroleum operators to achieve successful integrated land use during the past 20 years. The review illustrates how petroleum operators, in cooperation with local residents and communities, have planned and adapted specific aspects of different projects to address and resolve environmental and community concerns, and provides an overview of the measures that can be employed to achieve integrated land use planning guidelines for future projects. The review focuses on specific groups of renewable resources and the applicable measures that have been used to reduce industrial impacts to these resources which are very important to local residents. Community consultation processes in the planning region have been successfully used by local residents, government, and industry to identify concerns associated with petroleum projects, and to develop appropriate measures to address these concerns. Environmental protection planning measures are described for cultural and historical resources, air quality, noise, freshwater quality, marine water quality, terrain and soils, fisheries, and terrestrial and marine wildlife. General measures as well as specific protection procedures such as the beluga whale protection plan and oil spill contingency plans are discussed. Although some environmental accidents have occurred during petroleum exploration and drilling activities, evidence suggests that petroleum activity has been able to proceed with no detectable long-term impacts to the environment. 30 refs., 1 fig

  6. CHALLENGES OF ELECTRONIC INFORMATION RESOURCES IN ...

    African Journals Online (AJOL)

    This paper discusses the role of policy for proper and efficient library services in the electronic era. It points out some of the possible dangers of embarking in electronic resources without a proper focus at hand. Thus, it calls for today's librarians and policy makers to brainstorm and come up with working policies suitable to ...

  7. Structures in the K-shell delta electron spectrum near threshold for ionization by fast charged particles

    International Nuclear Information System (INIS)

    Amundsen, P.A.; Aashamar, K.

    Results of calculations of the delta electron spectrum for K-shell ionization of atoms by fast charged particles for target charges in the range 6 2 <=40 are presented. Appreciable structure is found in the spectrum near the ionization threshold, in particular for fast projectiles and heavy target elements. The structure can be quite sensitive to the details of the effective atomic potentials. (Auth.)

  8. Use of Electronic Resources in a Private University in Nigeria ...

    African Journals Online (AJOL)

    The study examined awareness and constraints in the use of electronic resources by lecturers and students of Ajayi Crowther University, Oyo, Nigeria. It aimed at justifying the resources expended in the provision of electronic resources in terms of awareness, patronage and factors that may be affecting awareness and use ...

  9. Electronic Resources Management System: Recommendation Report 2017

    KAUST Repository

    Ramli, Rindra M.

    2017-05-01

    This recommendation report provides an overview of the selection process for the new Electronic Resources Management System. The library has decided to move away from Innovative Interfaces Millennium ERM module. The library reviewed 3 system as potential replacements namely: Proquest 360 Resource Manager, Ex Libris Alma and Open Source CORAL ERMS. After comparing and trialling the systems, it was decided to go for Proquest 360 Resource Manager.

  10. Scarcity of Fresh Water Resources in the Ganges Delta of Bangladesh

    Science.gov (United States)

    Murshed, S. B.; Kaluarachchi, J. J.

    2017-12-01

    The Ganges Delta in Bangladesh is a classical example of water insecurity in a transboundary river basin where limitations in quantity, quality and timing of available water is producing disastrous conditions. Two opposite extreme water conditions, i.e., fresh water scarcity and floods are common in this region during dry and wet seasons, respectively. The purpose of this study is to manage fresh water requirement of people and environment considering the seasonal availability of surface water (SW) and ground water (GW). SW availability was analyzed by incoming stream flow including the effects of upstream water diversion, rainfall, temperature, evapotranspiration (ET). Flow duration curves (FDC), and rainfall and temperature elasticity are used to assess the change of incoming upstream flow. Groundwater data were collected from 285 piezometers and monitoring wells established by Bangladesh water development board. Variation of groundwater depth shows major withdrawals of GW are mostly concentrated in the north part of the study area. Irrigation is the largest sector of off-stream (irrigation, industrial and domestic) water use which occupies 82% SW and 17% GW of total water consumption. Although domestic water use is entirely depend on GW but arsenic pollution is limiting the GW use. FDC depicts a substantial difference between high flow threshold (20%) and low flow threshold (70%) in the Bangladesh part of Ganges River. A large variation of around 83% is observed for instream water volume between wet and dry seasons. The reduction of upstream fresh water flow increased the extent and intensity of salinity intrusion. Presently GW is also contaminated by saline water. This fresh water scarcity is reducing the livelihood options considerably and indirectly forcing population migration from the delta region. This study provides insight to the changes in hydrology and limitations to freshwater availability enabling better formulation of water resources management in

  11. Hot deformation behavior of delta-processed superalloy 718

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y., E-mail: wangyanhit@yahoo.cn [State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083 (China); School of Aeronautics and Astronautics, Central South University, Changsha 410083 (China); Shao, W.Z.; Zhen, L.; Zhang, B.Y. [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2011-03-25

    Research highlights: {yields} The peak stress for hot deformation can be described by the Z parameter. {yields} The grain size of DRX was inversely proportional to the Z parameter. {yields} The dissolution of {delta} phases was greatly accelerated under hot deformation. {yields}The {delta} phase stimulated nucleation can serve as the main DRX mechanism. - Abstract: Flow stress behavior and microstructures during hot compression of delta-processed superalloy 718 at temperatures from 950 to 1100 deg. C with strain rates of 10{sup -3} to 1 s{sup -1} were investigated by optical microscopy (OM), electron backscatter diffraction (EBSD) technique and transmission electron microscopy (TEM). The relationship between the peak stress and the deformation conditions can be expressed by a hyperbolic-sine type equation. The activation energy for the delta-processed superalloy 718 is determined to be 467 kJ/mol. The change of the dominant deformation mechanisms leads to the decrease of stress exponent and the increase of activation energy with increasing temperature. The dynamically recrystallized grain size is inversely proportional to the Zener-Hollomon (Z) parameter. It is found that the dissolution rate of {delta} phases under hot deformation conditions is much faster than that under static conditions. Dislocation, vacancy and curvature play important roles in the dissolution of {delta} phases. The main nucleation mechanisms of dynamic recrystallization (DRX) for the delta-processed superalloy 718 include the bulging of original grain boundaries and the {delta} phase stimulated DRX nucleation, which is closely related to the dissolution behavior of {delta} phases under certain deformation conditions.

  12. Effect of the hydrostatic pressure on the electron mobility in delta-doped systems

    Energy Technology Data Exchange (ETDEWEB)

    Oubram, O; Mora-Ramos, M E; Gaggero-Sager, L M, E-mail: 1gaggero@uaem.m [Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, CP 62209, Cuernavaca, Morelos (Mexico)

    2009-05-01

    The influence of hydrostatic pressure on the electron states and low-temperature mobility in n-type GaAs delta-doped single quantum wells is studied. Values of hydrostatic pressure consider are below the so-called GAMMA-X crossover, keeping all attention in the electronic properties at the Brillouin zone center. The effect of the pressure on the electron mobility is described via a relative quantity that is proportional to the ratio between P not = 0 and zero pressure results. Calculation is performed using an analytical description of the potential energy function profile, based on the Thomas-Fermi approach, taking explicitly into account the dependence upon P of the main input parameters: effective masses and dielectric constant. The relative mobility increases for higher values of P. The cases of zero and finite -although small- temperature are studied, showing that the influence of T is mainly to lower the values of the relative mobility in the entire range of P considered. Numerical results are reported for a two-dimensional density of ionized impurities equals to 7.5 x 10{sup 12} cm{sup -2}.

  13. use of electronic resources by graduate students of the department

    African Journals Online (AJOL)

    respondent's access electronic resources from the internet via Cybercafé .There is a high ... KEY WORDS: Use, Electronic Resources, Graduate Students, Cybercafé. INTRODUCTION ... Faculty of Education, University of Uyo, Uyo. Olu Olat ...

  14. Multimode delta-E effect magnetic field sensors with adapted electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Zabel, Sebastian; Fichtner, Simon; Kirchhof, Christine; Quandt, Eckhard; Faupel, Franz, E-mail: ff@tf.uni-kiel.de [Faculty of Engineering, Institute for Materials Science, Kiel University, Kaiserstraße 2, 24143 Kiel (Germany); Reermann, Jens; Schmidt, Gerhard [Faculty of Engineering, Institute for Electrical Engineering, Kiel University, Kaiserstraße 2, 24143 Kiel (Germany); Wagner, Bernhard [Fraunhofer Institute for Silicon Technology ISIT, Fraunhoferstraße 1, 25524 Itzehoe (Germany)

    2016-05-30

    We present an analytical and experimental study on low-noise piezoelectric thin film resonators that utilize the delta-E effect of a magnetostrictive layer to measure magnetic fields at low frequencies. Calculations from a physical model of the electromechanical resonator enable electrode designs to efficiently operate in the first and second transversal bending modes. As predicted by our calculations, the adapted electrode design improves the sensitivity by a factor of 6 and reduces the dynamic range of the sensor output by 16 dB, which significantly eases the requirements on readout electronics. Magnetic measurements show a bandwidth of 100 Hz at a noise level of about 100 pTHz{sup −0.5}.

  15. Tidal controls on river delta morphology

    Science.gov (United States)

    Hoitink, A. J. F.; Wang, Z. B.; Vermeulen, B.; Huismans, Y.; Kästner, K.

    2017-09-01

    River delta degradation has been caused by extraction of natural resources, sediment retention by reservoirs, and sea-level rise. Despite global concerns about these issues, human activity in the world’s largest deltas intensifies. Harbour development, construction of flood defences, sand mining and land reclamation emerge as key contemporary factors that exert an impact on delta morphology. Tides interacting with river discharge can play a crucial role in the morphodynamic development of deltas under pressure. Emerging insights into tidal controls on river delta morphology suggest that--despite the active morphodynamics in tidal channels and mouth bar regions--tidal motion acts to stabilize delta morphology at the landscape scale under the condition that sediment import during low flows largely balances sediment export during high flows. Distributary channels subject to tides show lower migration rates and are less easily flooded by the river because of opposing non-linear interactions between river discharge and the tide. These interactions lead to flow changes within channels, and a more uniform distribution of discharge across channels. Sediment depletion and rigorous human interventions in deltas, including storm surge defence works, disrupt the dynamic morphological equilibrium and can lead to erosion and severe scour at the channel bed, even decades after an intervention.

  16. Electronic resource management practical perspectives in a new technical services model

    CERN Document Server

    Elguindi, Anne

    2012-01-01

    A significant shift is taking place in libraries, with the purchase of e-resources accounting for the bulk of materials spending. Electronic Resource Management makes the case that technical services workflows need to make a corresponding shift toward e-centric models and highlights the increasing variety of e-formats that are forcing new developments in the field.Six chapters cover key topics, including: technical services models, both past and emerging; staffing and workflow in electronic resource management; implementation and transformation of electronic resource management systems; the ro

  17. Tides Stabilize Deltas until Humans Interfere

    Science.gov (United States)

    Hoitink, T.; Zheng Bing, W.; Vermeulen, B.; Huismans, Y.; Kastner, K.

    2017-12-01

    Despite global concerns about river delta degradation caused by extraction of natural resources, sediment retention by reservoirs and sea-level rise, human activity in the world's largest deltas intensifies. In this review, we argue that tides tend to stabilize deltas until humans interfere. Under natural circumstances, delta channels subject to tides are more stable than their fluvial-dominated counterparts. The oscillatory tidal flow counteracts the processes responsible for bank erosion, which explains why unprotected tidal channels migrate only slowly. Peak river discharges attenuate the tides, which creates storage space to accommodate the extra river discharge during extreme events and as a consequence, reduce flood risk. With stronger tides, the river discharge is being distributed more evenly over the various branches in a delta, preventing silting up of smaller channels. Human interference in deltas is massive. Storm surge barriers are constructed, new land is being reclaimed and large-scale sand excavation takes place, to collect building material. Evidence from deltas around the globe shows that in human-controlled deltas the tidal motion often plays a destabilizing role. In channels of the Rhine-Meuse Delta, some 100 scour holes are identified, which relates to the altered tidal motion after completion of a storm surge barrier. Sand mining has led to widespread river bank failures in the tidally-influenced Mekong Delta. The catastrophic flood event in the Gauges-Brahmaputra Delta by Cyclone Aila, which caused the inundation of an embanked polder area for over two years, was preceded by river bank erosion at the mouths of formal tidal channels that were blocked by the embankment. Efforts to predict the developments of degrading deltas are few. Existing delta models are capable of reproducing expanding deltas, which is essentially a matter of simulating the transport of sediment from source in a catchment to the sink in a delta. Processes of soil

  18. Utilization of electronic information resources by academic staff at ...

    African Journals Online (AJOL)

    The study investigated the utilization of Electronic Information resources by the academic staff of Makerere University in Uganda. It examined the academic staff awareness of the resources available, the types of resources provided by the Makerere University Library, the factors affecting resource utilization. The study was ...

  19. Delta-ray spectroscopy of quasi-atoms

    International Nuclear Information System (INIS)

    Kozhuharov, C.

    1983-01-01

    The spectroscopy of high energy delta-rays, emitted in collisions of very heavy ions, is studied. The ''orange''-type beta-spectrometer and the achromatic electron channel are the experimental setups. Delta ray production probabilities are studied as a function of the distance of closest approach R /SUB min/ or the impact parameter b. Coulomb ionization, ion trajectory, scaling laws, double differential cross sections, and K-X-rays information is extracted from the experiment. The dependence of delta-ray emission on the united charge number Z /SUB u/ is discussed. Asymmetric collision systems with Z x alpha approx. = 1 (delta ray spectrum from Pb→Sn collisions) are studied. Finally, very heavy collisions, such as 208 Pb + 208 Pb collisions at bombarding energy fas below the Coulomb barrier are touched upon

  20. Electronic Resources Management Project Presentation 2012

    KAUST Repository

    Ramli, Rindra M.

    2012-01-01

    This presentation describes the electronic resources management project undertaken by the KAUST library. The objectives of this project is to migrate information from MS Sharepoint to Millennium ERM module. One of the advantages of this migration

  1. Electron beam effects in auger electron spectroscopy and scanning electron microscopy

    International Nuclear Information System (INIS)

    Fontaine, J.M.; Duraud, J.P.; Le Gressus, C.

    1979-01-01

    Electron beam effects on Si(100) and 5% Fe/Cr alloy samples have been studied by measurements of the secondary electron yield delta, determination of the surface composition by Auger electron spectroscopy and imaging with scanning electron microscopy. Variations of delta as a function of the accelerating voltage Esub(p) (0.5 -9 Torr has no effect on technological samples covered with their reaction layers; the sensitivities to the beam depend rather on the earlier mechanical, thermal and chemical treatment of the surfaces. (author)

  2. Practical guide to electronic resources in the humanities

    CERN Document Server

    Dubnjakovic, Ana

    2010-01-01

    From full-text article databases to digitized collections of primary source materials, newly emerging electronic resources have radically impacted how research in the humanities is conducted and discovered. This book, covering high-quality, up-to-date electronic resources for the humanities, is an easy-to-use annotated guide for the librarian, student, and scholar alike. It covers online databases, indexes, archives, and many other critical tools in key humanities disciplines including philosophy, religion, languages and literature, and performing and visual arts. Succinct overviews of key eme

  3. Delta-electron spectroscopy: An aid for the determination of reaction times in heavy ion reactions

    International Nuclear Information System (INIS)

    Skapa, H.

    1983-01-01

    For the systems I->Au and I->Bi at an incident energy of 6.2 MeV/u (I->Au) and 6.6 MeV/u (I->Bi) the emission probability of delta electrons was determined. In an energy range from 150 KeV to 1000 KeV electrons were spectroscoped in coincidence to elastically, quasielastically, and deep inelastically scattered ions. In deep inelastic reaction between reaction products with high and without a mean mass drift was discriminated. The contribution of the conversion electrons, determined from gamma spectra, extends in the range of deep inelastic reactions of about 60%. While the ratio of conversion electrons for deep inelastic events with large to such without mass drift shows a flat, monotoneous growth for the ratio of the measured emission probabilities a oscillation-like structure with about 400 KeV width results. An interpretation of this structure as interference effect by nuclear time delay yields for the case of large mass drift a nuclear retention time of 7.5 x 10 -21 s. (orig./HSI) [de

  4. Utilisation of Electronic Information Resources By Lecturers in ...

    African Journals Online (AJOL)

    This study assesses the use of information resources, specifically, electronic databases by lecturers/teachers in Universities and Colleges of Education in South Western Nigeria. Information resources are central to teachers' education. It provides lecturers/teachers access to information that enhances research and ...

  5. LiDAR data for the Delta Area of California

    Data.gov (United States)

    California Natural Resource Agency — LiDAR data for the Delta Area of California from the California Department of Water Resources. Bare earth grids from LiDAR.This data is in ESRI Grid format with 2...

  6. Discipline, availability of electronic resources and the use of Finnish National Electronic Library - FinELib

    Directory of Open Access Journals (Sweden)

    Sanna Torma

    2004-01-01

    Full Text Available This study elaborated relations between digital library use by university faculty, users' discipline and the availability of key resources in the Finnish National Electronic Library (FinELib, Finnish national digital library, by using nationwide representative survey data. The results show that the perceived availability of key electronic resources by researchers in FinELib was a stronger predictor of the frequency and purpose of use of its services than users' discipline. Regardless of discipline a good perceived provision of central resources led to a more frequent use of FinELib. The satisfaction with the services did not vary with the discipline, but with the perceived availability of resources.

  7. The Role of the Acquisitions Librarian in Electronic Resources Management

    Science.gov (United States)

    Pomerantz, Sarah B.

    2010-01-01

    With the ongoing shift to electronic formats for library resources, acquisitions librarians, like the rest of the profession, must adapt to the rapidly changing landscape of electronic resources by keeping up with trends and mastering new skills related to digital publishing, technology, and licensing. The author sought to know what roles…

  8. Analysis of Pedagogic Potential of Electronic Educational Resources with Elements of Autodidactics

    Directory of Open Access Journals (Sweden)

    Igor A.

    2018-03-01

    Full Text Available Introduction: in recent years didactic properties of electronic educational resources undergo considerable changes, nevertheless, the question of studying of such complete phenomenon as “an electronic educational resource with autodidactics elements” remains open, despite sufficient scientific base of researches of the terms making this concept. Article purpose – determination of essence of electronic educational resources with autodidactics elements. Materials and Methods: the main method of research was the theoretical analysis of the pedagogical and psychological literature on the problem under study. We used the theoretical (analysis, synthesis, comparison and generalization methods, the method of interpretation, pedagogical modeling, and empirical methods (observation, testing, conversation, interview, analysis of students’ performance, pedagogical experiment, peer review. Results: we detected the advantages of electronic educational resources in comparison with traditional ones. The concept of autodidactics as applied to the subject of research is considered. Properties of electronic educational resources with a linear and nonlinear principle of construction are studied.The influence of the principle of construction on the development of the learners’ qualities is shown. We formulated an integral definition of electronic educational resources with elements of autodidactics, namely, the variability, adaptivity and cyclicity of training. A model of the teaching-learning process with electronic educational resources is developed. Discussion and Conclusions: further development of a problem will allow to define whether electronic educational resources with autodidactics elements pedagogical potential for realization of educational and self-educational activity of teachers have, to modify technological procedures taking into account age features of students, their specialties and features of the organization of process of training of

  9. Preservation and conservation of electronic information resources of ...

    African Journals Online (AJOL)

    The major holdings of the broadcast libraries of the Nigerian Television Authority (NTA) are electronic information resources; therefore, providing safe places for general management of these resources have aroused interest in the industry in Nigeria for sometimes. The need to study the preservation and conservation of ...

  10. Groundwater Flow Model of Göksu Delta Coastal Aquifer System

    Science.gov (United States)

    Erdem Dokuz, Uǧur; Çelik, Mehmet; Arslan, Şebnem; Engin, Hilal

    2016-04-01

    Like many other coastal areas, Göksu Delta (Mersin-Silifke, Southern Turkey) is a preferred place for human settlement especially due to its productive farmlands and water resources. The water dependent ecosystem in Göksu delta hosts about 332 different plant species and 328 different bird species besides serving for human use. Göksu Delta has been declared as Special Environmental Protection Zone, Wildlife Protection Area, and RAMSAR Convention for Wetlands of International Importance area. Unfortunately, rising population, agricultural and industrial activities cause degradation of water resources both by means of quality and quantity. This problem also exists for other wetlands around the world. It is necessary to prepare water management plans by taking global warming issues into account to protect water resources for next generations. To achieve this, the most efficient tool is to come up with groundwater management strategies by constructing groundwater flow models. By this aim, groundwater modeling studies were carried out for Göksu Delta coastal aquifer system. As a first and most important step in all groundwater modeling studies, geological and hydrogeological settings of the study area have been investigated. Göksu Delta, like many other deltaic environments, has a complex structure because it was formed with the sediments transported by Göksu River throughout the Quaternary period and shaped throughout the transgression-regression periods. Both due to this complex structure and the lack of observation wells penetrating deep enough to give an idea of the total thickness of the delta, it was impossible to reveal out the hydrogeological setting in a correct manner. Therefore, six wells were drilled to construct the conceptual hydrogeological model of Göksu Delta coastal aquifer system. On the basis of drilling studies and slug tests that were conducted along Göksu Delta, hydrostratigraphic units of the delta system have been obtained. According to

  11. Building an electronic resource collection a practical guide

    CERN Document Server

    Lee, Stuart D

    2004-01-01

    This practical book guides information professionals step-by-step through building and managing an electronic resource collection. It outlines the range of electronic products currently available in abstracting and indexing, bibliographic, and other services and then describes how to effectively select, evaluate and purchase them.

  12. Analysis of Human Resources Management Strategy in China Electronic Commerce Enterprises

    Science.gov (United States)

    Shao, Fang

    The paper discussed electronic-commerce's influence on enterprise human resources management, proposed and proved the human resources management strategy which electronic commerce enterprise should adopt from recruitment strategy to training strategy, keeping talent strategy and other ways.

  13. Using XML Technologies to Organize Electronic Reference Resources

    OpenAIRE

    Huser, Vojtech; Del Fiol, Guilherme; Rocha, Roberto A.

    2005-01-01

    Provision of access to reference electronic resources to clinicians is becoming increasingly important. We have created a framework for librarians to manage access to these resources at an enterprise level, rather than at the individual hospital libraries. We describe initial project requirements, implementation details, and some preliminary results.

  14. Wildlife resource utilisation at Moremi Game Reserve and Khwai community area in the Okavango Delta, Botswana.

    Science.gov (United States)

    Mbaiwa, Joseph E

    2005-10-01

    This paper uses the concept of sustainable development to examine the utilisation of wildlife resources at Moremi Game Reserve (MGR) and Khwai community area (NG 18/19) in the Okavango Delta, Botswana. Using both secondary and primary data sources, results show that the establishment of MGR in 1963 led to the displacement of Khwai residents from their land; affected Basarwa's hunting and gathering economy; marked the beginning of resource conflicts between Khwai residents and wildlife managers; and, led to the development of negative attitudes of Khwai residents towards wildlife conservation. Since the late 1980s, a predominantly foreign owned tourism industry developed in and around MGR, however, Khwai residents derive insignificant benefits from it and hence resource conflicts increased. In an attempt to address problems of resource conflicts and promote sustainable wildlife utilisation, the Botswana Government adopted the Community-Based Natural Resource Management (CBNRM) programme, which started operating at Khwai village in 2000. The CBNRM programme promotes local participation in natural resource management and rural development through tourism. It is beginning to have benefits to Khwai residents such as income generation, employment opportunities and local participation in wildlife management. These benefits from CBNRM are thus having an impact in the development of positive attitudes of Khwai residents towards wildlife conservation and tourism development. This paper argues that if extended to MGR, CBNRM has the potential of minimising wildlife conflicts between Khwai residents and the wildlife-tourism sectors. This approach may in the process promote the sustainable wildlife use in and around MGR.

  15. Energy deposition by delta rays

    International Nuclear Information System (INIS)

    Weigand, F.C.; Braby, L.A.

    1983-01-01

    Monte Carlo calculations for proton tracks were extended to projectile with more complex electronic structures which add additional delta ray production processes. An experimental apparatus was used to detect gas gain and resolution for H 2+ and 3 He ++

  16. Electronic Resources and Mission Creep: Reorganizing the Library for the Twenty-First Century

    Science.gov (United States)

    Stachokas, George

    2009-01-01

    The position of electronic resources librarian was created to serve as a specialist in the negotiation of license agreements for electronic resources, but mission creep has added more functions to the routine work of electronic resources such as cataloging, gathering information for collection development, and technical support. As electronic…

  17. Interface structure and electronic properties of SrTiO{sub 3} and YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} crystals and thin films

    Energy Technology Data Exchange (ETDEWEB)

    Thiess, S.

    2007-07-01

    Two new extensions of the X-ray standing wave (XSW) technique, made possible by the intense highly collimated X-ray beams from undulators at the ESRF, are described in this thesis. First, the XSW method was applied in a structural study to solve the nucleation mechanism of the high temperature superconductor YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} on the (001) surface of SrTiO{sub 3}. Second, the valence electronic structures of SrTiO{sub 3} and YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} were investigated. Finally, recent developments in the field of photoelectron spectroscopy in the hard X-ray region are described. The X-ray standing wave method is used in combination with fluorescence, Auger or photoelectron spectroscopy and lends very high spatial resolution power to these analytical techniques. Previously, the XSW method has been used for structure determination of surfaces and interfaces. The currently available X-ray intensities permit extensions to the XSW technique. Two recently established applications, described in this thesis, are XSW real space imaging and XSW valence electronic structure analysis. XSW real space imaging was employed to analyse the atomic structure of 0.5 and 1.0 layers of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} deposited on SrTiO{sub 3}(001). Three-dimensional images of the atomic distributions were reconstructed for each of the elements from experimentally determined Fourier components of the atomic distribution functions. The images confirmed the formation of a perovskite precursor phase prior to the formation of the YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} phase during the growth of the first monolayer of the film. XSW valence electronic structure analysis applied to SrTiO{sub 3} identified the valence band contributions arising from the strontium, titanium, and oxygen sites of the crystal lattice. Relations between the site-specific valence electronic structure and the lattice structure were established. The experimental results agree very well with

  18. Dendroclimatology of the Slave River Delta, Northwest Territories, Canada

    Science.gov (United States)

    Jarvis, S.; Buhay, W. M.; Blair, D.; Tardif, J.; Bailey, D.

    2004-05-01

    It is well documented that changing hydrological conditions impact delta ecosystems. Such changes can also affect local inhabitants who have historical connections to the area and its resources. During the summer of 2003 a multifaceted paleo-environmental project was initiated to reconstruct the frequencies of floods and droughts in the Slave River Delta (SRD), Northwest Territories, Canada. The project goal is to forecast future hydrological and ecological conditions in the SRD in light of anticipated climate change and increasing demand on water resources. With the intent of expanding the climate history of the SRD, this particular aspect of the project will employ white spruce tree-ring chronologies constructed from six sites visited within the delta. Work is currently in progress to build a master chronology estimated to span over 300 years. In addition, a climate model for the SRD is also being developed and will be highlighted.

  19. Conflicts over land in the Niger river delta region of Mali : exploring the usefulness of SAM and CGE models to study participatory natural resource management in agricultural and pastoral systems

    NARCIS (Netherlands)

    Kaboré, Pato Daniel

    2008-01-01

    The thesis deals with management of natural resources in the Niger Delta region of Mali. Climate changes and human activities have led to degradation of natural resources, whereas the demographic pressure increases. As a result, a social restructuring takes place: farmers are going to keep more

  20. Challenges Facing the Sacramento–San Joaquin Delta: Complex, Chaotic, or Simply Cantankerous?

    Directory of Open Access Journals (Sweden)

    Samuel N. Luoma

    2015-09-01

    Full Text Available doi: http://dx.doi.org/10.15447/sfews.2015v13iss3art7Freshwater is a scarce and precious resource in California; its overall value is being made clear by the current severe drought. The Sacramento–San Joaquin Delta is a critical node in a complex water supply system that extends throughout much of the western U.S. wherein demand is exceeding supply. The Delta also underpins a major component of the U.S. economy, helps feed a substantial part of the country, is a unique and valuable ecological resource, and is a place with a rich cultural heritage. Sustaining the Delta is a problem that manifests itself in many dimensions including the physical structure of the Delta, the conflicting demands for water, changing water quality, rapidly evolving ecological character, and high institutional complexity. The problems of the California Delta are increasingly complex, sometimes chaotic, and always contentious. There is general agreement that current management will sustain neither the Delta ecosystem nor high-quality water exports, as required under the Delta Reform Act, so there is a renewed urgency to address all dimensions of the problem aggressively. Sustainable management of the Delta ecosystem and California’s highly variable water supply, in the face of global climate change, will require bold political decisions that include adjustments to the infrastructure but give equal emphasis to chronic overuse and misuse of water, promote enhanced efficiency of water use, and facilitate new initiatives for ecosystem recovery. This new approach will need to be underpinned by collaborative science that supports ongoing evaluation and re-adjustment of actions. Problems like the Delta are formally “wicked" problems that cannot be “solved” in the traditional sense, but they can be managed with appropriate knowledge and flexible institutions. Where possible, it is advisable to approach major actions incrementally, with an eye toward avoiding

  1. 2016 Rose Ojowhoh Delta State Polytechnic, Ozoro

    African Journals Online (AJOL)

    OJOHWOH ROSE

    The study examined staff development and library services in academic libraries in Bayelsa and Delta States. ... academic libraries, whose responsibility will be to cater for the development of staff in all ramifications. ..... Human resource.

  2. Electronic Resources Management System: Recommendation Report 2017

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    This recommendation report provides an overview of the selection process for the new Electronic Resources Management System. The library has decided to move away from Innovative Interfaces Millennium ERM module. The library reviewed 3 system

  3. DELTAS: A new Global Delta Sustainability Initiative (Invited)

    Science.gov (United States)

    Foufoula-Georgiou, E.

    2013-12-01

    Deltas are economic and environmental hotspots, food baskets for many nations, home to a large part of the world population, and hosts of exceptional biodiversity and rich ecosystems. Deltas, being at the land-water interface, are international, regional, and local transport hubs, thus providing the basis for intense economic activities. Yet, deltas are deteriorating at an alarming rate as 'victims' of human actions (e.g. water and sediment reduction due to upstream basin development), climatic impacts (e.g. sea level rise and flooding from rivers and intense tropical storms), and local exploration (e.g. sand or aggregates, groundwater and hydrocarbon extraction). Although many efforts exist on individual deltas around the world, a comprehensive global delta sustainability initiative that promotes awareness, science integration, data and knowledge sharing, and development of decision support tools for an effective dialogue between scientists, managers and policy makers is lacking. Recently, the international scientific community proposed to establish the International Year of Deltas (IYD) to serve as the beginning of such a Global Delta Sustainability Initiative. The IYD was proposed as a year to: (1) increase awareness and attention to the value and vulnerability of deltas worldwide; (2) promote and enhance international and regional cooperation at the scientific, policy, and stakeholder level; and (3) serve as a launching pad for a 10-year committed effort to understand deltas as complex socio-ecological systems and ensure preparedness in protecting and restoring them in a rapidly changing environment. In this talk, the vision for such an international coordinated effort on delta sustainability will be presented as developed by a large number of international experts and recently funded through the Belmont Forum International Opportunities Fund. Participating countries include: U.S., France, Germany, U.K., India, Japan, Netherlands, Norway, Brazil, Bangladesh

  4. Dynamics of sustainability in integrated agriculture : aquaculture systems in the Mekong Delta

    NARCIS (Netherlands)

    Phong, L.T.

    2010-01-01

    Key words: Mekong Delta; IAA; ECOPATH; Nutmon; LCA; environmental impact; sustainability

    In the Mekong Delta (MD), intensification and modernization of crop, fish and livestock production causes concern about sustainable use of natural resources. The objectives of this research were to

  5. Global and local governance of shrimp farming in the Mekong Delta, Vietnam

    OpenAIRE

    Tran Thi Thu, H.

    2012-01-01

    The Mekong Delta is one of seven ecological regions in Vietnam where aquaculture and shrimp products are internationally traded and the shrimp farmers are firmly embedded in a global system of production and trade. The growth of shrimp aquaculture, in addition to population growth and higher levels of investment, has left coastal resources in the Mekong Delta increasingly vulnerable to rapid changes in land and resource use. The shrimp industry, made up of multiple stakeholders and fragmente...

  6. The Internet School of Medicine: use of electronic resources by medical trainees and the reliability of those resources.

    Science.gov (United States)

    Egle, Jonathan P; Smeenge, David M; Kassem, Kamal M; Mittal, Vijay K

    2015-01-01

    Electronic sources of medical information are plentiful, and numerous studies have demonstrated the use of the Internet by patients and the variable reliability of these sources. Studies have investigated neither the use of web-based resources by residents, nor the reliability of the information available on these websites. A web-based survey was distributed to surgical residents in Michigan and third- and fourth-year medical students at an American allopathic and osteopathic medical school and a Caribbean allopathic school regarding their preferred sources of medical information in various situations. A set of 254 queries simulating those faced by medical trainees on rounds, on a written examination, or during patient care was developed. The top 5 electronic resources cited by the trainees were evaluated for their ability to answer these questions accurately, using standard textbooks as the point of reference. The respondents reported a wide variety of overall preferred resources. Most of the 73 responding medical trainees favored textbooks or board review books for prolonged studying, but electronic resources are frequently used for quick studying, clinical decision-making questions, and medication queries. The most commonly used electronic resources were UpToDate, Google, Medscape, Wikipedia, and Epocrates. UpToDate and Epocrates had the highest percentage of correct answers (47%) and Wikipedia had the lowest (26%). Epocrates also had the highest percentage of wrong answers (30%), whereas Google had the lowest percentage (18%). All resources had a significant number of questions that they were unable to answer. Though hardcopy books have not been completely replaced by electronic resources, more than half of medical students and nearly half of residents prefer web-based sources of information. For quick questions and studying, both groups prefer Internet sources. However, the most commonly used electronic resources fail to answer clinical queries more than half

  7. The Legal Status of the Danube Delta Biosphere Reservation

    Directory of Open Access Journals (Sweden)

    Florica Brasoveanu

    2012-05-01

    Full Text Available In recent years the world has become aware that natural resources are not inexhaustible, that manyspecies are threatened with extinction and that is is necessary to strive for judicious use of natural resources tofulfill the needs of the present without compromising the ability of future generations to meet their needs(principle of sustainable development. To conserve species and habitats protected areas have beenestablished worldwide. The protected area is a geographically defined area, with rare natural elements and / orendangered species, regulated and managed in order to achieve specific conservation objectives. Althoughranked Europe's second in size (after the Volga River and the 20th in the world, because of the rich landscapeand wildlife, with the birds ranked most important, the Danube Delta has a very special interest scientificallyas it is a natural laboratory of forming delta, tourism and economic ecosystems, through its renewable naturalresources of which the most important resources are living aquatic resources.

  8. ANALYTICAL REVIEW OF ELECTRONIC RESOURCES FOR THE STUDY OF LATIN

    Directory of Open Access Journals (Sweden)

    Olena Yu. Balalaieva

    2014-04-01

    Full Text Available The article investigates the current state of development of e-learning content in the Latin language. It is noted that the introduction of ICT in the educational space has expanded the possibility of studying Latin, opened access to digital libraries resources, made it possible to use scientific and educational potential and teaching Latin best practices of world's leading universities. A review of foreign and Ukrainian information resources and electronic editions for the study of Latin is given. Much attention was paid to the didactic potential of local and online multimedia courses of Latin, electronic textbooks, workbooks of interactive tests and exercises, various dictionaries and software translators, databases and digital libraries. Based on analysis of the world market of educational services and products the main trends in the development of information resources and electronic books are examined. It was found that multimedia courses with interactive exercises or workbooks with interactive tests, online dictionaries and translators are the most widely represented and demanded. The noticeable lagging of Ukrainian education and computer linguistics in quantitative and qualitative measures in this industry is established. The obvious drawback of existing Ukrainian resources and electronic editions for the study of Latin is their noninteractive nature. The prospects of e-learning content in Latin in Ukraine are outlined.

  9. Elektronik Bilgi Kaynaklarının Seçimi / Selection of Electronic Information Resources

    Directory of Open Access Journals (Sweden)

    Pınar Al

    2003-04-01

    Full Text Available For many years, library users have used only from the printed media in order to get the information that they have needed. Today with the widespread use of the Web and the addition of electronic information resources to library collections, the use of information in the electronic environment as well as in printed media is started to be used. In time, such types of information resources as, electronic journals, electronic books, electronic encyclopedias, electronic dictionaries and electronic theses have been added to library collections. In this study, selection criteria that can be used for electronic information resources are discussed and suggestions are provided for libraries that try to select electronic information resources for their collections.

  10. Determining Water Quality Trends in the Sacramento-San Joaquin Delta Watershed in the Face of Climate Change

    Science.gov (United States)

    Kynett, K.; Azimi-Gaylon, S.; Doidic, C.

    2014-12-01

    The Sacramento-San Joaquin Delta and Suisun Marsh (Delta) is the largest estuary on the West Coast of the Americas and is a resource of local, State, and national significance. The Delta is simultaneously the most critical component of California's water supply, a primary focus of the state's ecological conservation measures, and a vital resource deeply imperiled by degraded water quality. Delta waterbodies are identified as impaired by salinity, excess nutrients, low dissolved oxygen, pathogens, pesticides, heavy metals, and other contaminants. Climate change is expected to exacerbate the impacts of existing stressors in the Delta and magnify the challenges of managing this natural resource. A clear understanding of the current state of the watershed is needed to better inform scientists, decision makers, and the public about potential impacts from climate change. The Delta Watershed Initiative Network (Delta WIN) leverages the ecological benefits of healthy watersheds, and enhances, expands and creates opportunities for greater watershed health by coordinating with agencies, established programs, and local organizations. At this critical junction, Delta WIN is coordinating data integration and analysis to develop better understanding of the existing and emerging water quality concerns. As first steps, Delta WIN is integrating existing water quality data, analyzing trends, and monitoring to fill data gaps and to evaluate indicators of climate change impacts. Available data will be used for trend analysis; Delta WIN will continue to monitor where data is incomplete and new questions arise. Understanding how climate change conditions may affect water quality will be used to inform efforts to build resilience and maintain water quality levels which sustain aquatic life and human needs. Assessments of historical and new data will aid in recognition of potential climate change impacts and in initiating implementation of best management practices in collaboration with

  11. Investigation of transient processes at the DELTA electron storage ring using a digital bunch-by-bunch feedback system

    Energy Technology Data Exchange (ETDEWEB)

    Hoener, Markus

    2015-07-01

    At the 1.5-GeV synchrotron radiation source DELTA, operated by the TU Dortmund University, intensive synchrotron radiation in the spectral range from hard X-rays to THz radiation is generated by the circular deflection of highly relativistic electron bunches. Interacting with the vacuum chamber wall, the electron bunches create electric fields, which can act back on subsequent bunches. With increasing beam current, the excitation is enhanced so that the electron beam is unstable, which means that the electron bunches oscillate longitudinally or transversely relative to their reference position. The oscillations reduce the quality of the synchrotron radiation and limit the maximum storable beam current. Within the scope of this thesis, the beam instabilities at the storage ring were systematically investigated. A digital bunch-by-bunch feedback system was installed and commissioned, which allows to detect and digitize the position of each electron bunch at each turn. Based on the input signal, a correction signal is calculated in order to suppress transverse and longitudinal oscillation of the bunches. In addition, it is possible to excite dedicated bunches. The systematic excitation of all coupled-bunch modes allowed for the first time to determine the damping rates of all 192 eigenmodes of the electron beam. The current dependence of the damping rates was investigated and an instability threshold was found. Besides the investigation of multibunch instabilities, single-bunch instabilities are discussed. In addition, the acquisition unit of the digital feedback system can be triggered on external events. This was used to investigate the injection process and beam losses. It was shown that the transverse feedback system increases the injection efficiency. Another aspect of this thesis is the improvement of the signal quality of ultrashort coherent synchrotron radiation pulses, which are generated by the short-pulse facility at DELTA. The short-pulse facility is based

  12. Vulnerability and Resilience of the Niger Delta Coastal Communities to Pollution and Environmental Degradation

    Science.gov (United States)

    Ndimele, P. E.; Whenu, O. O.; Anwan, H. R.; Anetekhai, M. A.

    2016-02-01

    The Niger Delta is Africa's largest delta consisting of the third largest mangrove forest in the world and covering 70,000km2 of Nigeria land mass. This delta is the largest wetland in Africa and among the ten most important wetland and marine ecosystems in the world. The delta is home to all of Nigeria's endemic or near-endemic mammal species and to six IUCN Red List mammals. The Niger Delta harbours globally outstanding fish fauna and displays exceptional evolutionary phenomena with its higher taxonomic endemism and distinct species assemblages. The Niger delta is blessed with abundance of natural and human resources, including the majority of Nigeria's oil and gas deposits, good agricultural land, extensive forests, excellent fisheries as well as a well-developed industrial base, a large labour force and a vibrant private sector. However, this fragile but rich ecosystem is seriously threatened by increased industrial pollution, resource over-exploitation and environmental degradation caused by over six decades of oil exploitation. Aquatic life has been destroyed with the pollution of traditional fishing grounds, exacerbating hunger and poverty in fishing communities. The multifarious use of the delta has led to human-induced changes in biota, habitats and landscapes necessitating the development of a holistic policy that considers all the interacting factors in the ecosystem. Taking a systems approach incorporating an understanding of The Ecosystem Approach, vulnerability, resilience, the DPSIR framework, ecosystem services and societal benefits are integrated in order to evolve a management tool that will result in sustainable resource exploitation, improvement in living standards of locals and restoration of the ecosystem.

  13. Access to electronic resources by visually impaired people

    Directory of Open Access Journals (Sweden)

    Jenny Craven

    2003-01-01

    Full Text Available Research into access to electronic resources by visually impaired people undertaken by the Centre for Research in Library and Information Management has not only explored the accessibility of websites and levels of awareness in providing websites that adhere to design for all principles, but has sought to enhance understanding of information seeking behaviour of blind and visually impaired people when using digital resources.

  14. Library training to promote electronic resource usage

    DEFF Research Database (Denmark)

    Frandsen, Tove Faber; Tibyampansha, Dativa; Ibrahim, Glory

    2017-01-01

    Purpose: Increasing the usage of electronic resources is an issue of concern for many libraries all over the world. Several studies stress the importance of information literacy and instruction in order to increase the usage. Design/methodology/approach: The present article presents the results...

  15. Why and How to Measure the Use of Electronic Resources

    Directory of Open Access Journals (Sweden)

    Jean Bernon

    2008-11-01

    Full Text Available A complete overview of library activity implies a complete and reliable measurement of the use of both electronic resources and printed materials. This measurement is based on three sets of definitions: document types, use types and user types. There is a common model of definitions for printed materials, but a lot of questions and technical issues remain for electronic resources. In 2006 a French national working group studied these questions. It relied on the COUNTER standard, but found it insufficient and pointed out the need for local tools such as web markers and deep analysis of proxy logs. Within the French national consortium COUPERIN, a new working group is testing ERMS, SUSHI standards, Shibboleth authentication, along with COUNTER standards, to improve the counting of the electronic resources use. At this stage this counting is insufficient and its improvement will be a European challenge for the future.

  16. Delta self-consistent field method to obtain potential energy surfaces of excited molecules on surfaces

    DEFF Research Database (Denmark)

    Gavnholt, Jeppe; Olsen, Thomas; Engelund, Mads

    2008-01-01

    is a density-functional method closely resembling standard density-functional theory (DFT), the only difference being that in Delta SCF one or more electrons are placed in higher lying Kohn-Sham orbitals instead of placing all electrons in the lowest possible orbitals as one does when calculating the ground......-state energy within standard DFT. We extend the Delta SCF method by allowing excited electrons to occupy orbitals which are linear combinations of Kohn-Sham orbitals. With this extra freedom it is possible to place charge locally on adsorbed molecules in the calculations, such that resonance energies can...... be estimated, which is not possible in traditional Delta SCF because of very delocalized Kohn-Sham orbitals. The method is applied to N2, CO, and NO adsorbed on different metallic surfaces and compared to ordinary Delta SCF without our modification, spatially constrained DFT, and inverse...

  17. Resource intensification and osteoarthritis patterns: changes in activity in the prehistoric Sacramento-San Joaquin Delta region.

    Science.gov (United States)

    Cheverko, Colleen M; Bartelink, Eric J

    2017-10-01

    Ethnohistoric accounts and archaeological research from Central California document a shift from the use of lower-cost, high-ranked resources (e.g., large game) toward the greater use of higher-cost, low-ranked resources (e.g., acorns and small seeds) during the Late Holocene (4500-200 BP). The subsistence transition from higher consumption of large game toward an increased reliance on acorns was likely associated with increases in levels of logistical mobility and physical activity. This study predicts that mobility and overall workload patterns changed during this transition to accommodate new food procurement strategies and incorporate new dietary resources during the Late Holocene in Central California. Osteoarthritis prevalence was scored in the shoulder, elbow, hip, and knee of adult individuals (n = 256) from seven archaeological sites in the Sacramento-San Joaquin Delta region. Comparisons were made between osteoarthritis prevalence, sex, age-at-death, and time period using ANCOVAs. The results of this study indicate significant increases in osteoarthritis prevalence in the hip of adult males and females during the Late Period (1200-200 BP), even after correcting for the cumulative effects of age. No differences were observed between the sexes or between time periods for the shoulder, elbow, and knee joints. The temporal increase in hip osteoarthritis supports the hypothesis that there was an increasing need for greater logistical mobility over time to procure key resources away from the village sites. Additionally, the lack of sex differences in osteoarthritis prevalence may suggest that females and males likely performed similar levels of activity during these periods. © 2017 Wiley Periodicals, Inc.

  18. Perspectives on bay-delta science and policy

    Science.gov (United States)

    Healey, Michael; Dettinger, Michael; Norgaard, Richard

    2016-01-01

    The State of Bay–Delta Science 2008 highlighted seven emerging perspectives on science and management of the Delta. These perspectives had important effects on policy and legislation concerning management of the Delta ecosystem and water exports. From the collection of papers that make up the State of Bay–Delta Science 2016, we derive another seven perspectives that augment those published in 2008. The new perspectives address nutrient and contaminant concentrations in Delta waters, the failure of the Delta food web to support native species, the role of multiple stressors in driving species toward extinction, and the emerging importance of extreme events in driving change in the ecosystem and the water supply. The scientific advances that underpin these new perspectives were made possible by new measurement and analytic tools. We briefly discuss some of these, including miniaturized acoustic fish tags, sensors for monitoring of water quality, analytic techniques for disaggregating complex contaminant mixtures, remote sensing to assess levee vulnerability, and multidimensional hydrodynamic modeling. Despite these new tools and scientific insights, species conservation objectives for the Delta are not being met. We believe that this lack of progress stems in part from the fact that science and policy do not incorporate sufficiently long-term perspectives. Looking forward half a century was central to the Delta Visioning process, but science and policy have not embraced this conceptual breadth. We are also concerned that protection and enhancement of the unique cultural, recreational, natural resource, and agricultural values of the Delta as an evolving place, as required by the Delta Reform Act, has received no critical study and analysis. Adopting wider and longer science and policy perspectives immediately encourages recognition of the need for evaluation, analysis, and public discourse on novel conservation approaches. These longer and wider perspectives

  19. Perspectives on Bay–Delta Science and Policy

    Directory of Open Access Journals (Sweden)

    Michael Healey

    2016-12-01

    Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art6The State of Bay–Delta Science 2008 highlighted seven emerging perspectives on science and management of the Delta. These perspectives had important effects on policy and legislation concerning management of the Delta ecosystem and water exports. From the collection of papers that make up the State of Bay–Delta Science 2016, we derive another seven perspectives that augment those published in 2008. The new perspectives address nutrient and contaminant concentrations in Delta waters, the failure of the Delta food web to support native species, the role of multiple stressors in driving species toward extinction, and the emerging importance of extreme events in driving change in the ecosystem and the water supply. The scientific advances that underpin these new perspectives were made possible by new measurement and analytic tools. We briefly discuss some of these, including miniaturized acoustic fish tags, sensors for monitoring of water quality, analytic techniques for disaggregating complex contaminant mixtures, remote sensing to assess levee vulnerability, and multidimensional hydrodynamic modeling. Despite these new tools and scientific insights, species conservation objectives for the Delta are not being met. We believe that this lack of progress stems in part from the fact that science and policy do not incorporate sufficiently long-term perspectives. Looking forward half a century was central to the Delta Visioning process, but science and policy have not embraced this conceptual breadth. We are also concerned that protection and enhancement of the unique cultural, recreational, natural resource, and agricultural values of the Delta as an evolving place, as required by the Delta Reform Act, has received no critical study and analysis. Adopting wider and longer science and policy perspectives immediately encourages recognition of the need for evaluation, analysis, and public discourse on

  20. Euler European Libraries and Electronic Resources in Mathematical Sciences

    CERN Document Server

    The Euler Project. Karlsruhe

    The European Libraries and Electronic Resources (EULER) Project in Mathematical Sciences provides the EulerService site for searching out "mathematical resources such as books, pre-prints, web-pages, abstracts, proceedings, serials, technical reports preprints) and NetLab (for Internet resources), this outstanding engine is capable of simple, full, and refined searches. It also offers a browse option, which responds to entries in the author, keyword, and title fields. Further information about the Project is provided at the EULER homepage.

  1. Acid Rain in Niger Delta Region: Implication on Water Resources ...

    African Journals Online (AJOL)

    This research focused on the effect of acid rain on the water quality of the Niger Delta region of Nigeria. Three hundred water samples were collected: 100 water samples from rain, 100 from open wells and 100 from rivers. The water samples were analysed using the paired t-test and multiple correlation analysis to ascertain ...

  2. The State of Bay–Delta Science 2016: An Introduction

    Directory of Open Access Journals (Sweden)

    Michael Healey

    2016-07-01

    Full Text Available doi: http://dx.doi.org/10.15447/sfews.2016v14iss2art5The State of Bay–Delta Science 2016 (SBDS is a collection of papers that summarizes the scientific understanding of the Sacramento–San Joaquin Delta, emphasizing progress made during the past decade.It builds on the first SBDS edition (Healey et al. 2008. Paper topics for this edition address the most relevant scientific issues in the Delta identified by senior scientists and managers. The topical papers cover issues ranging from contaminants in the Delta to levee stability, and from Delta food webs to recent discoveries about salmon migration. These papers are written for a scientific audience. Two additional papers, one describing the challenges of managing water and ecosystems in the Delta and another that discusses policy implications of the recent scientific findings, are written for a general audience. The papers will be published in at least two issues of San Francisco Estuary and Watershed Science and will be available as a set electronically.

  3. Hole states in diamond p-delta-doped field effect transistors

    International Nuclear Information System (INIS)

    Martinez-Orozco, J C; Rodriguez-Vargas, I; Mora-Ramos, M E

    2009-01-01

    The p-delta-doping in diamond allows to create high density two-dimensional hole gases. This technique has already been applied in the design and fabrication of diamond-based field effect transistors. Consequently, the knowledge of the electronic structure is of significant importance to understand the transport properties of diamond p-delta-doped systems. In this work the hole subbands of diamond p-type delta-doped quantum wells are studied within the framework of a local-density Thomas-Fermi-based approach for the band bending profile. The calculation incorporates an independent three-hole-band scheme and considers the effects of the contact potential, the delta-channel to contact distance, and the ionized impurity density.

  4. Hole states in diamond p-delta-doped field effect transistors

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Orozco, J C; Rodriguez-Vargas, I [Unidad Academica de Fisica, Universidad Autonoma de Zacatecas, Calzada Solidaridad Esquina con Paseo la Bufa S/N, CP 98060 Zacatecas, ZAC. (Mexico); Mora-Ramos, M E, E-mail: jcmover@correo.unam.m [Facultad de Ciencias, Universidad Autonoma del Estado de Morelos, Av. Universidad 1001, Col. Chamilpa, CP 62209 Cuernavaca, MOR. (Mexico)

    2009-05-01

    The p-delta-doping in diamond allows to create high density two-dimensional hole gases. This technique has already been applied in the design and fabrication of diamond-based field effect transistors. Consequently, the knowledge of the electronic structure is of significant importance to understand the transport properties of diamond p-delta-doped systems. In this work the hole subbands of diamond p-type delta-doped quantum wells are studied within the framework of a local-density Thomas-Fermi-based approach for the band bending profile. The calculation incorporates an independent three-hole-band scheme and considers the effects of the contact potential, the delta-channel to contact distance, and the ionized impurity density.

  5. Effects of Electronic Information Resources Skills Training for Lecturers on Pedagogical Practices and Research Productivity

    Science.gov (United States)

    Bhukuvhani, Crispen; Chiparausha, Blessing; Zuvalinyenga, Dorcas

    2012-01-01

    Lecturers use various electronic resources at different frequencies. The university library's information literacy skills workshops and seminars are the main sources of knowledge of accessing electronic resources. The use of electronic resources can be said to have positively affected lecturers' pedagogical practices and their work in general. The…

  6. The first hop: Use of Beaufort Sea deltas by hatch-year semipalmated sandpipers

    Science.gov (United States)

    Churchwell, Roy T.; Kendall, Steve J.; Brown, Stephen C.; Blanchard, Arny L.; Hollmen, Tuula E.; Powell, Abby

    2018-01-01

    River deltas along Alaska’s Beaufort Sea coast are used by hatch-year semipalmated sandpipers (Calidris pusilla) after leaving their terrestrial natal sites, but the drivers of their use of these stopover sites on the first “hop” of fall migration are unknown. We quantified sandpiper temporal distribution and abundance as related to food resources at three river deltas during the beginning of their fall migration (post-breeding period) to compare the habitat quality among these deltas. We conducted population counts, sampled invertebrates, and captured birds to collect blood samples from individuals for triglyceride and stable isotope analyses to determine fattening rates and diet. Patterns of sandpiper and invertebrate abundance were complex and varied among deltas and within seasons. River deltas were used by sandpipers from late July to late August, and peak sandpiper counts ranged from 1000 to 4000 individuals, of which 98% were hatch-year semipalmated sandpipers. Isotopic signatures from blood plasma samples indicated that birds switched from a diet of upland tundra to delta invertebrate taxa as the migration season progressed, suggesting a dependence on delta invertebrates. Despite differences in diet among deltas, we found no differences in fattening rates of juvenile sandpipers as indicated by triglyceride levels. The number of sandpipers was positively associated with abundance of Amphipoda and Oligochaeta at the Jago and Okpilak-Hulahula deltas; an isotopic mixing model indicated that sandpipers consumed Amphipoda and Oligochaeta at Jago, mostly Chironomidae at Okpilak-Hulahula and Spionidae at Canning. Regardless of the difference in sandpiper diets at the Beaufort Sea deltas, their similar fattening rates throughout the season indicate that all of these stopover sites provide a critical food resource for hatch-year sandpipers beginning their first migration.

  7. The impact of human activities in the Wulan Delta Estuary, Indonesia

    Science.gov (United States)

    Fadlillah, L. N.; Sunarto; Widyastuti, M.; Marfai, M. A.

    2018-04-01

    The increasing of human population in the watershed and the coastal area and the need of life exert pressure in the delta that provides various resources. Wulan Delta is one of active Delta in Central Java, Indonesia. It has been experienced multiple pressures because of natural factors and human factors. In order to provide the scientific solution and to analyze the impact of human intervention in delta, we collected several pieces of evidence based on secondary data and primary data. The secondary data is water quality data on sites 6 and 7, meanwhile the secondary data is the water quality data in site 1 to 5. This paper present a review and problems identification in Wulan Delta, based on hydrological condition, land use, and human activities in the delta. Meanwhile, the human intervention in the land which is land use exchange leads to several problems such as the land use changes, high sediment load, and water degradation. Almost 80% of Delta has been transformed into the fish pond by local communities.

  8. Tracks, spurs, blobs and delta-rays

    International Nuclear Information System (INIS)

    Magee, J.L.; Chatterjee, A.

    1983-01-01

    The track of a high-energy particle is the collection of all transient species created by the particle in the total degradation of its energy. Visible electron tracks are called delta rays. A microscopic description of the track with all its knocked-out electrons leads to spurs, blobs, and short tracks. Energy deposition criteria for these three track entities are 6 to 100 eV, 100 to 500 eV, and 500 eV to 5 keV, respectively

  9. Electronic Commerce Resource Centers. An Industry--University Partnership.

    Science.gov (United States)

    Gulledge, Thomas R.; Sommer, Rainer; Tarimcilar, M. Murat

    1999-01-01

    Electronic Commerce Resource Centers focus on transferring emerging technologies to small businesses through university/industry partnerships. Successful implementation hinges on a strategic operating plan, creation of measurable value for customers, investment in customer-targeted training, and measurement of performance outputs. (SK)

  10. VTVH-MCD study of the Delta nifB Delta nifZ MoFe protein from Azotobacter vinelandii.

    Science.gov (United States)

    Cotton, Marcia S; Rupnik, Kresimir; Broach, Robyn B; Hu, Yilin; Fay, Aaron W; Ribbe, Markus W; Hales, Brian J

    2009-04-08

    NifZ is a member of a series of proteins associated with the maturation of the nitrogenase MoFe protein. An MCD spectroscopic study was undertaken on the Delta nifB Delta nifZ MoFe protein generated in the absence of both NifZ and NifB (deletion of NifB generates an apo-MoFe protein lacking the FeMo cofactor). Results presented here show that, in the absence of NifZ, only one of the two P-clusters of the MoFe protein is matured to the ultimate [8Fe-7S] structure. The other P-cluster site in the protein contains a [4Fe-4S] cluster pair, representing a P-cluster precursor that is electronically identical to the analogous clusters observed in the Delta nifH MoFe protein. These results suggest that the MoFe protein is synthesized in a stepwise fashion where NifZ is specifically required for the formation of the second P-cluster.

  11. Reactivity, structure and physical properties of SrCo{sub 2.5+{delta}} and La{sub 2}CoO{sub 4.0+{delta}}. In situ X-ray diffraction and neutrons study; Reactivite, structure et proprietes physiques de SrCoO{sub 2.5+{delta}} et La{sub 2}CoO{sub 4.0+{delta}}. Etude par diffraction des rayons X et des neutrons in situ

    Energy Technology Data Exchange (ETDEWEB)

    Le Toquin, R.

    2003-11-15

    This work was devoted to the study of the reactivity and more specifically the influence of the intercalated oxygen amount {delta} on the structure and physical properties of SrCoO{sub 2.5+{delta}} et La{sub 2}CoO{sub 4.0+{delta}} We controlled the oxidation level by means of reversible electrochemical red ox reaction at room temperature. Structural modifications, especially disorder, and electronic properties were studied for the first time on large orientated single crystal. In the SrCoO{sub 2.5+{delta}} system, after structural and electronic characterisation of the end phases, we studied the real structure of the brownmillerite SrCoO{sub 2.5} phase using single crystal. Moreover, we investigated structural and magnetic evolution upon red ox cycle using X-ray diffraction on 6 times twinned single crystal and in situ neutron powder diffraction. Two intermediate SrCoO{sub 2.75} and SrCoO{sub 2.82} phases have been observed. The reaction on single crystal has evidenced the evolution of domain structure. For the La{sub 2}CoO{sub 4+{delta}} system, we synthesised a large variety of single crystal with stoichiometry {delta} 0.0, 0.09, 0.12, 0.16, 0.20 and 0.25. Using single crystal X-ray and neutron diffraction, we showed a disorder-order transition of the apical and interstitial oxygen for the higher {delta} values. (author)

  12. 2007 California Department of Water Resources Topographic LiDAR: San Joaquin Delta

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from LIDAR flights of the Sacramento-San Joaquin Delta conducted during late January and February of 2007. The work was conducted under contract...

  13. EEHG at FLASH and DELTA

    Energy Technology Data Exchange (ETDEWEB)

    Molo, Robert; Hoener, Markus; Huck, Holger; Hacker, Kirsten; Khan, Shaukat; Schick, Andreas; Ungelenk, Peter; Zeinalzadeh, Maryam [Center for Synchrotron Radiation (DELTA), TU Dortmund University (Germany); Meulen, Peter van der; Salen, Peter [Stockholm University (Sweden); Angelova Hamberg, Gergana; Ziemann, Volker [Uppsala University (Sweden)

    2013-07-01

    The echo-enabled harmonic generation (EEHG) scheme utilizes two modulators with two magnetic chicanes in order to generate an electron density modulation with high harmonic content. In contrast to free-electron lasers (FEL) based on self-amplified spontaneous emission (SASE), the radiation of an EEHG FEL has better longitudinal coherence and is naturally synchronized with an external laser, which is advantageous for pump-probe applications. At the free-electron laser in Hamburg (FLASH), an EEHG experiment is currently under preparation. The short-pulse facility at DELTA (a 1.5-GeV synchrotron light source operated by the TU Dortmund University) based on coherent harmonic generation (CHG) will be upgraded using the EEHG technique in order to reach shorter wavelengths.

  14. Studies of Louisiana's Deltas and Wetlands using SAR

    Science.gov (United States)

    Jones, C. E.

    2017-12-01

    Sustainable coastal environments exist in delicate balance between subsidence, erosion, and sea level rise on one hand and accretion of sediment and retention of decomposing organic matter on the other. In this talk we present results from a series of studies using an airborne L-band SAR (UAVSAR) to measure changing conditions in the Mississippi River Delta and coastal wetlands of Louisiana. Change within the Mississippi River delta (MRD), which is a highly engineered environment, is contrasted to those in the Wax Lake Delta, a small, naturally evolving delta located to the west of the current-day lobe of the MRD. The UAVSAR studies provide evidence that in the MRD subsidence and erosion related to human activities are increasing risk of flooding, submergence, and land loss. These are not seen in the Wax Lake Delta, where new land is forming. We evaluate geomorphic and hydrologic changes In the Wax Lake Delta and wetlands hydrologically connected to the Wax Lake Outlet canal that are apparent on the timescales of the UAVSAR data set, which consists of both near-yearly acquisitions (2009-2016) and several series of repeat acquisitions in 2015 and 2016 capturing conditions across a tidal cycle. Using the yearly data, we observe the evolution of subaqueous channels and crevasses in the delta and changes in distributary channels within the wetlands. We use water level change derived from InSAR applied to the rapid repeat data acquired during different stages of a tidal cycle to study the natural pattern of water flux within the delta and the coastal wetlands. The studies, results, and plans for future work will be presented. This work was carried out in part at the Jet Propulsion Laboratory, California Institute of Technology, under contracts with the California Dept. of Water Resources and with the National Aeronautics and Space Administration.

  15. Influence of different organic fertilizers on quality parameters and the delta(15)N, delta(13)C, delta(2)H, delta(34)S, and delta(18)O values of orange fruit (Citrus sinensis L. Osbeck).

    Science.gov (United States)

    Rapisarda, Paolo; Camin, Federica; Fabroni, Simona; Perini, Matteo; Torrisi, Biagio; Intrigliolo, Francesco

    2010-03-24

    To investigate the influence of different types of fertilizers on quality parameters, N-containing compounds, and the delta(15)N, delta(13)C, delta(2)H, delta (34)S, and delta(18)O values of citrus fruit, a study was performed on the orange fruit cv. 'Valencia late' (Citrus sinensis L. Osbeck), which was harvested in four plots (three organic and one conventional) located on the same farm. The results demonstrated that different types of organic fertilizers containing the same amount of nitrogen did not effect important changes in orange fruit quality parameters. The levels of total N and N-containing compounds such as synephrine in fruit juice were not statistically different among the different treatments. The delta(15)N values of orange fruit grown under fertilizer derived from animal origin as well as from vegetable compost were statistically higher than those grown with mineral fertilizer. Therefore, delta(15)N values can be used as an indicator of citrus fertilization management (organic or conventional), because even when applied organic fertilizers are of different origins, the natural abundance of (15)N in organic citrus fruit remains higher than in conventional ones. These treatments also did not effect differences in the delta(13)C, delta(2)H, delta(34)S, and delta(18)O values of fruit.

  16. Challenges, Approaches and Experiences from Asian Deltas and the Rhine-Meuse Delta : Regional Training Workshop on Delta Planning and Management

    NARCIS (Netherlands)

    Wosten, J.H.M.; Douven, W.; Long Phi, H.; Fida Abdullah Khan, M.

    2013-01-01

    River delta's, like the Mekong Delta (Vietnam), Ganges-Brahmaputra Delta (Bangladesh), Ayeyarwady Delta (Myanmar), Nile (Egypt) and Ciliwung Delta (Indonesia) are developing rapidly and are characterised by large-scale urbanisation and industrialization processes. They are facing serious planning

  17. Femosecond dynamics of quasi-particles in YBa sub 2 Cu sub 3 O sub 7 minus. delta. superconductor films

    Energy Technology Data Exchange (ETDEWEB)

    Han, S.G.; Vardeny, Z.V.; Symko, O.G. (Utah Univ., Salt Lake City, UT (United States). Dept. of Physics); Koren, G. (Technion-Israel Inst. of Tech., Haifa (Israel). Dept. of Physics)

    1991-03-01

    This paper reports on the transient electronic response of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} epitaxially grown HT{sub c} superconductor thin films in the femtosecond time domain, using transient photoinduced reflectivity ({Delta}R) with 60 fsec time resolution. For temperatures T {gt} T{sub c} only a bolometric signal was observed with {Delta}R {gt} O. For T {lt} T{sub c} {Delta}R {lt} O with a temperature dependent rise time of order 300 fsec followed by a relaxation (of order 3 psec) into a state with {Delta} are explained in terms of quasi-particle (QP) electronic response giving {Delta}R {lt} O. Thus the femtosecond rise time is interpreted as avalanche multiplication of QP across the gap 2{Delta} and the subsequent picosecond relaxation as QP recombination. The QP optical response is explained within the two fluid model.

  18. Delta Plaza kohvik = Delta Plaza cafe

    Index Scriptorium Estoniae

    2010-01-01

    Tallinnas Pärnu mnt 141 asuva kohviku Delta Plaza sisekujundusest. Sisearhitektid Tiiu Truus ja Marja Viltrop (Stuudio Truus OÜ). Tiiu Truusi tähtsamate tööde loetelu. Büroohoone Delta Plaza arhitektid Marika Lõoke ja Jüri Okas (AB J. Okas & M. Lõoke)

  19. Growth laws for sub-delta crevasses in the Mississippi River Delta

    Science.gov (United States)

    Yocum, T. A.; Georgiou, I. Y.; Straub, K. M.

    2017-12-01

    River deltas are threatened by environmental change, including subsidence, global sea level rise, reduced sediment inputs and other local factors. In the Mississippi River Delta (MRD) these impacts are exemplified, and have led to proposed solutions to build land that include sediment diversions to reinitiate the delta cycle. Deltas were studied extensively using numerical models, theoretical and conceptual frameworks, empirical scaling relationships, laboratory models and field observations. But predicting the future of deltas relies on field observations where for most deltas data are still lacking. Moreover, empirical and theoretical scaling laws may be influenced by the data used to develop them, while laboratory deltas may be influenced by scaling issues. Anthropogenic crevasses in the MRD are large enough to overcome limitations of laboratory deltas, and small enough to allow for rapid channel and wetland development, providing an ideal setting to investigate delta development mechanics. Here we assessed growth laws of sub-delta crevasses (SDC) in the MRD, in two experimental laboratory deltas (LD - weakly and strongly cohesive) and compared them to river dominated deltas worldwide. Channel and delta geometry metrics for each system were obtained using geospatial tools, bathymetric datasets, sediment size, and hydrodynamic observations. Results show that SDC follow growth laws similar to large river dominated deltas, with the exception of some that exhibit anomalous behavior with respect to the frequency and distance to a bifurcation and the fraction of wetted delta shoreline (allometry metrics). Most SDC exhibit a systematic decrease of non-dimensional channel geometries with increased bifurcation order, indicating that channels are adjusting to decreased flow after bifurcations occur, and exhibit linear trends for land allometry and width-depth ratio, although geometries decrease more rapidly per bifurcation order. Measured distance to bifurcations in SDC

  20. USE OF ELECTRONIC EDUCATIONAL RESOURCES WHEN TRAINING IN WORK WITH SPREADSHEETS

    Directory of Open Access Journals (Sweden)

    Х А Гербеков

    2017-12-01

    Full Text Available Today the tools for maintaining training courses based on opportunities of information and communication technologies are developed. Practically in all directions of preparation and on all subject matters electronic textbook and self-instruction manuals are created. Nevertheless the industry of computer educational and methodical materials actively develops and gets more and more areas of development and introduction. In this regard more and more urgent is a problem of development of the electronic educational resources adequate to modern educational requirements. Creation and the organization of training courses with use of electronic educational resources in particular on the basis of Internet technologies remains a difficult methodical task.In article the questions connected with development of electronic educational resources for use when studying the substantial line “Information technologies” of a school course of informatics in particular for studying of spreadsheets are considered. Also the analysis of maintenance of a school course and the unified state examination from the point of view of representation of task in him corresponding to the substantial line of studying “Information technologies” on mastering technology of information processing in spreadsheets and the methods of visualization given by means of charts and schedules is carried out.

  1. Delta antibody radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Kselikova, M; Urbankova, J

    1985-11-15

    The principle and procedure are described of the radioimmunoassay of delta antibody (delta-Ab) using the ABBOTT ANTI-DELTA kit by Abbott Co. A description is given of the kit, the working procedure and the method of evaluation. The results are reported of the incidence of delta-Ab in sera of patients with viral hepatitis B, in haemophiliacs, carriers of the hepatitis B virus surface antigen (HBsAg) and blood donors. The presence was detected of delta-Ab in one HBsAg carrier. The necessity is emphasized of delta-Ab determinations in the blood of donors in view of the antibody transfer with blood and blood preparations.

  2. Perceptions versus Realities: Exploring Needs and Science Learning Outcomes In the Mississippi Delta

    Science.gov (United States)

    Fitts, Lacey S.

    The Mississippi Delta (MS Delta) is a high-poverty region in northwestern Mississippi located between the Mississippi and Yazoo rivers. The Delta is home to sixteen rural counties with over seventy failing or underperforming schools. Many of these schools lack the resources necessary to ensure adequate opportunities for all students. Learning outcomes for the state are among the lowest in the nation, and scores in the rural Delta are far below the state average. Graduating seniors take the ACT college entrance exam, with about 10% of Mississippi seniors scoring as "college-ready" in science. The region has a critical shortage of science teachers, and many schools do not offer advanced science courses. This study assessed teachers' needs, identified key characteristics of the secondary science programs in which they teach, and sought to understand conditions affecting science learning outcomes. An inventory of science teachers' needs was administered to teachers in the region. The greatest needs were material resources, high quality training, and strategies for improving poor reading and problem-solving skills of students. Of the factors examined, the percentage of students receiving free lunch had the strongest correlation with science learning outcomes in the school, higher than access to resources, number of science courses offered, and level of self-reported teacher need. A three-tiered approach to improving science learning outcomes has been developed, emphasizing community relationships, targeted professional development, and relevant science curriculum.

  3. A novel mouse PKC{delta} splice variant, PKC{delta}IX, inhibits etoposide-induced apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jung D. [School of Biological Sciences, University of Ulsan, Ulsan (Korea, Republic of); Seo, Kwang W. [Department of Internal Medicines, Ulsan University Hospital and School of Medicine, University of Ulsan, Ulsan (Korea, Republic of); Lee, Eun A.; Quang, Nguyen N. [School of Biological Sciences, University of Ulsan, Ulsan (Korea, Republic of); Cho, Hong R. [Department of Surgery, Ulsan University Hospital and School of Medicine, University of Ulsan, Ulsan (Korea, Republic of); Biomedical Research Center, Ulsan University Hospital and School of Medicine, University of Ulsan, Ulsan (Korea, Republic of); Kwon, Byungsuk, E-mail: bskwon@mail.ulsan.as.kr [School of Biological Sciences, University of Ulsan, Ulsan (Korea, Republic of); Biomedical Research Center, Ulsan University Hospital and School of Medicine, University of Ulsan, Ulsan (Korea, Republic of)

    2011-07-01

    Highlights: {yields} A novel PKC{delta} isoform, named PKC{delta}IX, that lacks the C1 domain and the ATP-binding site is ubiquitously expressed. {yields} PKC{delta}IX inhibits etoposide-induced apoptosis. {yields} PKC{delta}IX may function as an endogenous dominant negative isoform for PKC{delta}. -- Abstract: Protein kinase C (PKC) {delta} plays an important role in cellular proliferation and apoptosis. The catalytic fragment of PKC{delta} generated by caspase-dependent cleavage is essential for the initiation of etoposide-induced apoptosis. In this study, we identified a novel mouse PKC{delta} isoform named PKC{delta}IX (Genebank Accession No. (HQ840432)). PKC{delta}IX is generated by alternative splicing and is ubiquitously expressed, as seen in its full-length PKC{delta}. PKC{delta}IX lacks the C1 domain, the caspase 3 cleavage site, and the ATP binding site but preserves an almost intact c-terminal catalytic domain and a nuclear localization signal (NLS). The structural characteristics of PKC{delta}IX provided a possibility that this PKC{delta} isozyme functions as a novel dominant-negative form for PKC{delta} due to its lack of the ATP-binding domain that is required for the kinase activity of PKC{delta}. Indeed, overexpression of PKC{delta}IX significantly inhibited etoposide-induced apoptosis in NIH3T3 cells. In addition, an in vitro kinase assay showed that recombinant PKC{delta}IX protein could competitively inhibit the kinase activity of PKC{delta}. We conclude that PKC{delta}IX can function as a natural dominant-negative inhibitor of PKC{delta}in vivo.

  4. Intergranular corrosion behavior associated with delta-ferrite transformation of Ti-modified Super304H austenitic stainless steel

    International Nuclear Information System (INIS)

    Bai, Guanshun; Lu, Shanping; Li, Dianzhong; Li, Yiyi

    2015-01-01

    Highlights: • Relationship between delta-ferrite transformation and IGC behavior was evaluated by DL-EPR test quantitatively. • The IGC site at austenite/ferrite grain boundary changes with aging time at 650 °C. • A higher fraction of delta-ferrite with poor stability increases the IGC sensitisation. • Self-healing of IGC was mainly induced by the Cr diffusion from primary austenite rather than the delta-ferrite. - Abstract: A double loop electrochemical potentiokinetic reactivation (DL-EPR) test was conducted to investigate the relationship between the evolution of delta-ferrite and the intergranular corrosion (IGC) of Ti-modified Super304H, which was aged at 650 °C for 4–500 h. Scanning electron microscopy and transmission electron microscopy were adopted to analyze the evolution of delta-ferrite. The results indicated that a higher fraction of delta-ferrite with poor stability increased the IGC sensitisation of Ti-modified Super304H. Moreover, the self-healing of the sensitisation of Ti-modified Super304H occurred after 48 h due to the diffusion of chromium atoms mainly from the adjacent primary austenite rather than the delta-ferrite

  5. [Preparation and spectral analysis of a new type of blue light-emitting material delta-Alq3].

    Science.gov (United States)

    Wang, Hua; Hao, Yu-ying; Gao, Zhi-xiang; Zhou, He-feng; Xu, Bing-she

    2006-10-01

    In the present article, delta-Alq3, a new type of blue light-emitting material, was synthesized and investigated by IR spectra, XRD spectra, UV-Vis absorption spectra, photoluminescence (PL) spectra, and electroluminescence (EL) spectra. The relationship between molecular spatial structure and spectral characteristics was studied by the spectral analysis of delta-Alq3 and alpha-Alq3. Results show that a new phase of Alq3 (delta-Alq3) can be obtained by vacuum heating alpha-Alq3, and the molecular spatial structure of alpha-Alq3 changes during the vacuum heating. The molecular spatial structure of delta-Alq3 lacks symmetry compared to alpha-Alq3. This transformation can reduce the electron cloud density on phenoxide of Alq3 and weaken the intermolecular conjugated interaction between adjacent Alq3 molecules. Hence, the pi--pi* electron transition absorption peak of delta-Alq3 shifts toward short wavelength in UV-Vis absorption spectra, and the maximum emission peak of delta-Alq3 (lamda max = 480 nm) blue-shifts by 35 nm compared with that of alpha-Alq3 (lamda max = 515 nm) in PL spectra. The maximum emission peaks of delta-Alq3 and alpha-Alq3 are all at 520 nm in EL spectra.

  6. Analytical Study of Usage of Electronic Information Resources at Pharmacopoeial Libraries in India

    Directory of Open Access Journals (Sweden)

    Sunil Tyagi

    2014-02-01

    Full Text Available The objective of this study is to know the rate and purpose of the use of e-resource by the scientists at pharmacopoeial libraries in India. Among other things, this study examined the preferences of the scientists toward printed books and journals, electronic information resources, and pattern of using e-resources. Non-probability sampling specially accidental and purposive technique was applied in the collection of primary data through administration of user questionnaire. The sample respondents chosen for the study consists of principle scientific officer, senior scientific officer, scientific officer, and scientific assistant of different division of the laboratories, namely, research and development, pharmaceutical chemistry, pharmacovigilance, pharmacology, pharmacogonosy, and microbiology. The findings of the study reveal the personal experiences and perceptions they have had on practice and research activity using e-resource. The major findings indicate that of the total anticipated participants, 78% indicated that they perceived the ability to use computer for electronic information resources. The data analysis shows that all the scientists belonging to the pharmacopoeial libraries used electronic information resources to address issues relating to drug indexes and compendia, monographs, drugs obtained through online databases, e-journals, and the Internet sources—especially polices by regulatory agencies, contacts, drug promotional literature, and standards.

  7. Enhancing stakeholder participation in the Niger Delta region: the ...

    African Journals Online (AJOL)

    Nigeria's indigenous people, found in the Niger Delta area, have for many years experienced developmental challenges associated with oil exploration. The region has been perennially engulfed in various forms of agitation pertaining to self-government and resource control. Over the years, attempts to solve these ...

  8. Page 170 Use of Electronic Resources by Undergraduates in Two ...

    African Journals Online (AJOL)

    undergraduate students use electronic resources such as NUC virtual library, HINARI, ... web pages articles from magazines, encyclopedias, pamphlets and other .... of Nigerian university libraries have Internet connectivity, some of the system.

  9. Delta Dynamics

    DEFF Research Database (Denmark)

    Bendixen, Mette

    . The warming air temperature affects the soil temperature and permafrost thaws and destabilizes the material in the coastal zone. In Greenland, the warming temperature lowers the surface mass balance of the Greenland Ice Sheet and more material is transported to the coastal zone. The sea ice extent is thinning...... of a fjord and the second type is a wider fan-shaped open delta. Most deltas are directly coupled to the Greenland Ice Sheet or local icecaps and are highly influenced by the dynamics in the catchments. It is demonstrated how a modern changing climate directly affects delta dynamics, and that Greenlandic...... deltas are prograding, contrary to the global trend showing eroding Arctic coasts. Moreover, it is revealed that the increasing proglacial freshwater runoff, caused by a lowering of the surface mass balance of the Greenland Ice Sheet is the main determining agent in delta progradation. The final part...

  10. Study on the willingness of Sfantu Gheorghe fishermen community, from Danube Delta, to involve in decision making regarding biodiversity conservation by switching from sturgeon fishing to other natural resources

    Directory of Open Access Journals (Sweden)

    BOZAGIEVICI Raluca

    2011-09-01

    Full Text Available The investigation aimed to find out local knowledge on biodiversity conservation through sustainable use and the willingness of the local community Sfântu Gheorghe, Danube Delta, to be involved in the decision making process regarding the sustainable use of the natural resources. In obtaining the necessary information, structuredinterviews and focus group were conducted with the local population and stakeholders in order to achieve a clearer picture of all aspects of sustainable use of natural resources within the area. The results highlighted the unwillingness of local people to exploit the alternative natural resources, other than fish, available in the area and the lack of a strategy to inform and support the local community to realize projects pursuing the recovery of these resources.

  11. Holocene evolution of a wave-dominated fan-delta: Godavari delta, India

    Science.gov (United States)

    Saito, Y.; Nageswara Rao, K.; Nagakumar, K.; Demudu, G.; Rajawat, A.; Kubo, S.; Li, Z.

    2013-12-01

    The Godavari delta is one of the world's largest wave-dominated deltas. The Godavari River arises in the Western Ghats near the west coast of India and drains an area of about 3.1x10^5 km^2, flowing about 1465 km southeast across the Indian peninsula to the Bay of Bengal. The Godavari delta consists of a gentle seaward slope from its apex (12 m elevation) at Rajahmundry and a coastal beach-ridge plain over a distance of about 75 km and covers ~5200 km^2 as a delta plain. The river splits into two major distributary channels, the Gautami and the Vasishta, at a barrage constructed in the mid-1800s. The coastal environment of the deltaic coast is microtidal (~1 m mean tidal range) and wave-dominated (~1.5 m mean wave height in the June-September SW monsoon season, ~0.8 m in the NE monsoon season). Models of the Holocene evolution of the Godavari delta have changed from a zonal progradation model (e.g. Nageswara Rao & Sadakata, 1993) to a truncated cuspate delta model (Nageswara Rao et al., 2005, 2012). Twelve borehole cores (340 m total length), taken in the coastal delta plain during 2010-2013, yielded more than 100 C-14 dates. Sediment facies and C-14 dates from these and previous cores and remote-sensing data support a new delta evolution model. The Holocene coastal delta plain is divided into two parts by a set of linear beach ridges 12-14 km landward from the present shoreline in the central part of the delta. The location of the main depocenter (lobe) has shifted during the Holocene from 1) the center to 2) the west, 3) east, 4) center, 5) west, and 6) east. The linear beach ridges separate the first three from the last three stages. These lobe shifts are controlled by river channel shifts near the apex. Just as the current linear shoreline of the central part of the delta and the concave-up nearshore topography are the result of coastal erosion of a cuspate delta, the linear beach ridges indicate a former eroded shoreline. An unconformity within the deltaic

  12. Model of e-learning with electronic educational resources of new generation

    Directory of Open Access Journals (Sweden)

    A. V. Loban

    2017-01-01

    Full Text Available Purpose of the article: improving of scientific and methodical base of the theory of the е-learning of variability. Methods used: conceptual and logical modeling of the е-learning of variability process with electronic educational resource of new generation and system analysis of the interconnection of the studied subject area, methods, didactics approaches and information and communication technologies means. Results: the formalization complex model of the е-learning of variability with electronic educational resource of new generation is developed, conditionally decomposed into three basic components: the formalization model of the course in the form of the thesaurusclassifier (“Author of e-resource”, the model of learning as management (“Coordination. Consultation. Control”, the learning model with the thesaurus-classifier (“Student”. Model “Author of e-resource” allows the student to achieve completeness, high degree of didactic elaboration and structuring of the studied material in triples of variants: modules of education information, practical task and control tasks; the result of the student’s (author’s of e-resource activity is the thesaurus-classifier. Model of learning as management is based on the principle of personal orientation of learning in computer environment and determines the logic of interaction between the lecturer and the student when determining the triple of variants individually for each student; organization of a dialogue between the lecturer and the student for consulting purposes; personal control of the student’s success (report generation and iterative search for the concept of the class assignment in the thesaurus-classifier before acquiring the required level of training. Model “Student” makes it possible to concretize the learning tasks in relation to the personality of the student and to the training level achieved; the assumption of the lecturer about the level of training of a

  13. Low-energy positron and electron diffraction and positron-stimulated secondary electron emission from Cu(100)

    International Nuclear Information System (INIS)

    Weiss, A.H.

    1983-01-01

    The results of two series of experiments are reported. In the first, an electrostatically guided beam of low-energy (40-400 eV) positrons, delta/sub p/ was used to study low-energy positron diffraction (LEPD) from a Cu(100) surface under ultrahigh-vacuum conditions. Low-energy electron diffraction (LEED) data were obtained from the same sample in the same apparatus. Comparison of LEPD and LEED intensity versus energy data with model calculations made using computer programs developed by C.B. Duke and collaborators indicated that: LEPD data is adequately modeled using potentials with no exchange-correlation term. The inelastic mean free path, lambda/sub ee/, is shorter for positrons than for electrons at low (< approx.80 eV). LEED is better than LEPD at making a determination of the first-layer spacing of Cu(100) for the particular data set reported. In the second set of experiments, the same apparatus and sample were used to compare positron- and electron-stimulated secondary-electron emission (PSSEE and ESSEE). The results were found to be consistent with existing models of secondary-electron production for metals. The energy distributions of secondary-electrons had broad low-energy (<10 eV) peaks for both positron and electron stimulation. But the PSEE distribution showed no elastic peak. Measurements of secondary-electron angular distributions, found to be cosine-like in both the PSSEE and ESSEE case, were used to obtain total secondary yield ratios, delta, at four beam energies ranging from 40-400 eV. The secondary yield ratio for primary positrons and the yield for primary electrons, delta/sub e/, were similar at these energies. For 400-eV primary particles the secondary yields were found to be delta/sub p/ = 0.94 +/- 0.12 and delta/sub e/ = 0.94 +/- 0./12, giving a ratio of unity for positron-stimulated secondary yield to electron-stimulated secondary yield

  14. A survey of the use of electronic scientific information resources among medical and dental students

    Directory of Open Access Journals (Sweden)

    Aarnio Matti

    2006-05-01

    Full Text Available Abstract Background To evaluate medical and dental students' utilization of electronic information resources. Methods A web survey sent to 837 students (49.9% responded. Results Twenty-four per cent of medical students and ninteen per cent of dental students searched MEDLINE 2+ times/month for study purposes, and thiry-two per cent and twenty-four per cent respectively for research. Full-text articles were used 2+ times/month by thirty-three per cent of medical and ten per cent of dental students. Twelve per cent of respondents never utilized either MEDLINE or full-text articles. In multivariate models, the information-searching skills among students were significantly associated with use of MEDLINE and full-text articles. Conclusion Use of electronic resources differs among students. Forty percent were non-users of full-text articles. Information-searching skills are correlated with the use of electronic resources, but the level of basic PC skills plays not a major role in using these resources. The student data shows that adequate training in information-searching skills will increase the use of electronic information resources.

  15. Access to electronic information resources by students of federal ...

    African Journals Online (AJOL)

    The paper discusses access to electronic information resources by students of Federal Colleges of Education in Eha-Amufu and Umunze. Descriptive survey design was used to investigate sample of 526 students. Sampling technique used was a Multi sampling technique. Data for the study were generated using ...

  16. Adoption and use of electronic information resources by medical ...

    African Journals Online (AJOL)

    This study investigated the adoption and use of electronic information resources by medical science students of the University of Benin. The descriptive survey research design was adopted for the study and 390 students provided the data. Data collected were analysed with descriptive Statistics(Simple percentage and ...

  17. Fabrication of an integrated {Delta}E-E-silicon detector by wafer bonding using cobalt disilicide

    Energy Technology Data Exchange (ETDEWEB)

    Thungstroem, G. [Mid-Sweden Univ., Sundsvall (Sweden). Dept. of Inf. Technol.]|[Royal Institute of Technology, Department of Electronics, Electrum 229, S-164 40 Kista (Sweden); Veldhuizen, E.J. van [Uppsala University, Department of Radiation Science, Box 535, S-751 21 Uppsala (Sweden); Westerberg, L. [Uppsala University, The Svedberg Laboratory, Box 533, S-751 21 Uppsala (Sweden); Norlin, L.-O. [Royal Institute of Technology, Department of Physics, Frescativaegen 24, S-104 05 Stockholm (Sweden); Petersson, C.S. [Royal Institute of Technology, Department of Electronics, Electrum 229, S-164 40 Kista (Sweden)

    1997-06-01

    The problem concerning mechanical stability of thin self-supporting {Delta}E detector in a {Delta}E-E semiconductor detector telescope, has been solved by integrating both detectors into one unit. We show here a low-cost method to integrate the detectors by wafer bonding using cobalt disilicide. The {Delta}E-detector has a thickness of 6.5 {mu}m and the E detector 290 {mu}m with an area of 24.8 mm{sup 2}. The system was characterized with secondary ion mass spectroscopy (SIMS), scanning electron microscopy (SEM), electrical measurement, particle measurement and two-dimensional electrical simulation. (orig.).

  18. Anaerobic Transformation of Furfural by Methanococcus deltae (Delta)LH

    Science.gov (United States)

    Belay, N.; Boopathy, R.; Voskuilen, G.

    1997-01-01

    Methanococcus deltae (Delta)LH was grown on H(inf2)-CO(inf2) in the presence of various concentrations of furfural. Furfural at higher concentrations, namely, 20 and 25 mM, inhibited growth of this organism. At concentration of 5 and 10 mM, no inhibition of growth was observed. The other methanogens in this study were not inhibited by 10 mM furfural. Among the methanogens tested, M. deltae was capable of transforming furfural, whereas Methanobacterium thermoautotrophicum Marburg, Methanosarcina barkeri 227, Methanococcus thermolithotrophicus, and Methanobrevibacter ruminantium lacked this capability. One hundred percent removal of furfural was observed within 48 h of incubation in M. deltae cultures. The end product observed during furfural metabolism was furfuryl alcohol. An almost stoichiometric amount of furfuryl alcohol was produced by M. deltae. This transformation is likely to be of value in the detoxification of furfural and in its ultimate conversion to methane and CO(inf2) by anaerobic digestion. PMID:16535618

  19. Where Do Electronic Books Fit in the College Research Arsenal of Resources?

    Science.gov (United States)

    Barbier, Patricia

    2007-01-01

    Student use of electronic books has become an accepted supplement to traditional resources. Student use and satisfaction was monitored through an online course discussion board. Increased use of electronic books indicate this service is an accepted supplement to the print book collection.

  20. Usage of shape of signal from liquid ionization chamber for rejection delta electrons and multiple measurement of dE/d x

    International Nuclear Information System (INIS)

    Kulinich, P.A.

    1994-01-01

    The results of numerical simulation of separation of different kinds of charged particles with β 2 cm) ionization liquid medium chamber is proposed to be used for rejection of energetic delta electrons and for few measurements of dE/d x inside one gap. Possibility of separating π- and k-mesons at the level of 2 σ in a 4 cm L Kr medium chamber in the momentum range (0.5 N - 0.8) GeV/c is shown. 15 refs.; 13 figs.; 3 tabs. (author)

  1. Nonadiabatic anharmonic electron transfer

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, P. P. [Molecular Physics Research, 6547 Kristina Ursula Court, Falls Church, Virginia 22044 (United States)

    2013-03-28

    The effect of an inner sphere, local mode vibration on an electron transfer is modeled using the nonadiabatic transition probability (rate) expression together with both the anharmonic Morse and the harmonic oscillator potential. For an anharmonic inner sphere mode, a variational analysis uses harmonic oscillator basis functions to overcome the difficulties evaluating Morse-model Franck-Condon overlap factors. Individual matrix elements are computed with the use of new, fast, robust, and flexible recurrence relations. The analysis therefore readily addresses changes in frequency and/or displacement of oscillator minimums in the different electron transfer states. Direct summation of the individual Boltzmann weighted Franck-Condon contributions avoids the limitations inherent in the use of the familiar high-temperature, Gaussian form of the rate constant. The effect of harmonic versus anharmonic inner sphere modes on the electron transfer is readily seen, especially in the exoergic, inverted region. The behavior of the transition probability can also be displayed as a surface for all temperatures and values of the driving force/exoergicity {Delta}=-{Delta}G. The temperature insensitivity of the transfer rate is clearly seen when the exoergicity equals the collective reorganization energy ({Delta}={Lambda}{sub s}) along a maximum ln (w) vs. {Delta} ridge of the surface. The surface also reveals additional regions for {Delta} where ln (w) appears to be insensitive to temperature, or effectively activationless, for some kinds of inner sphere contributions.

  2. Controlling the Electronic Properties in La1/3Sr 2/3FeO3-delta Complex Perovskite Oxides

    Science.gov (United States)

    Krick, Alex L.

    the temperature-dependent resistivity. Carrier behavior within the superlattices was also explored by fitting the temperature dependent resistivity to common conduction models. The conduction mechanism fits show that the transport at high temperatures is dominated by weakly insulating behavior due to small polaron conduction and at low temperatures the resistivity can be fit to both a novel power law and 3-dimensional variable range hopping. Additionally, reversible changes of the structural and electronic transport properties of La1/3Sr2/3FeO3-delta/Gd-doped CeO2 (GDC) heterostructures arising from the manipulation of delta are presented. Thermally induced oxygen loss leads to a c-axis lattice expansion and an increase in resistivity in an LSFO film capped with GDC. In a three-terminal device where a gate bias is applied across the GDC layer to alter the LSFO oxygen stoichiometry, the ferrite channel is shown to undergo an order of magnitude change in resistance using gate voltages of less than 1 V applied at 500 K. The changes in resistance remain upon cooling to room temperature, in the absence of a gate bias, suggesting solid state ionic gating of perovskite oxides as a promising platform for applications in non-volatile, multistate devices. Along with the experiments of controlling delta in a device format, the kinetics of oxygen loss as a function of biaxial strain was investigated.

  3. HDVDB: a data warehouse for hepatitis delta virus.

    Science.gov (United States)

    Singh, Sarita; Gupta, Sunil Kumar; Nischal, Anuradha; Pant, Kamlesh Kumar; Seth, Prahlad Kishore

    2015-01-01

    Hepatitis Delta Virus (HDV) is an RNA virus and causes delta hepatitis in humans. Although a lot of data is available for HDV, but retrieval of information is a complicated task. Current web database 'HDVDB' provides a comprehensive web-resource for HDV. The database is basically concerned with basic information about HDV and disease caused by this virus, genome structure, pathogenesis, epidemiology, symptoms and prevention, etc. Database also supplies sequence data and bibliographic information about HDV. A tool 'siHDV Predict' to design the effective siRNA molecule to control the activity of HDV, is also integrated in database. It is a user friendly information system available at public domain and provides annotated information about HDV for research scholars, scientists, pharma industry people for further study.

  4. Growth laws for delta crevasses in the Mississippi River Delta: observations and modeling

    Science.gov (United States)

    Yocum, T. A.; Georgiou, I. Y.

    2016-02-01

    River deltas are accumulations of sedimentary deposits delivered by rivers via a network of distributary channels. Worldwide they are threatened by environmental changes, including subsidence, global sea level rise and a suite of other local factors. In the Mississippi River Delta (MRD) these impacts are exemplified, and have led to proposed solutions to build land that include sediment diversions, thereby reinitiating the delta cycle. While economically efficient, there are too few analogs of small deltas aside from laboratory studies, numerical modeling studies, theoretical approaches, and limited field driven observations. Anthropogenic crevasses in the modern delta are large enough to overcome limitations of laboratory deltas, and small enough to allow for "rapid" channel and wetland development, providing an ideal setting to investigate delta development mechanics. Crevasse metrics were obtained using a combination of geospatial tools, extracting key parameters (bifurcation length and width, channel order and depth) that were non-dimensionalized and compared to river-dominated delta networks previously studied. Analysis showed that most crevasses in the MRD appear to obey delta growth laws and delta allometry relationships, suggesting that crevasses do exhibit similar planform metrics to larger Deltas; the distance to mouth bar versus bifurcation order demonstrated to be a very reasonable first order estimate of delta-top footprint. However, some crevasses exhibited different growth metrics. To better understand the hydrodynamic and geomorphic controls governing crevasse evolution in the MRD, we assess delta dynamics via a suite of field observations and numerical modeling in both well-established and newly constructed crevasses. Our analysis suggests that delta development is affected by the relative influence of external (upstream and downstream) and internal controls on the hydrodynamic and sediment transport patterns in these systems.

  5. COMMD1 regulates the delta epithelial sodium channel ({delta}ENaC) through trafficking and ubiquitination

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Tina; Ke, Ying; Ly, Kevin [Department of Physiology, University of Otago, P.O. Box 913, Dunedin 9054 (New Zealand); McDonald, Fiona J., E-mail: fiona.mcdonald@otago.ac.nz [Department of Physiology, University of Otago, P.O. Box 913, Dunedin 9054 (New Zealand)

    2011-08-05

    Highlights: {yields} The COMM domain of COMMD1 mediates binding to {delta}ENaC. {yields} COMMD1 reduces the cell surface population of {delta}ENaC. {yields} COMMD1 increases the population of {delta}ENaC-ubiquitin. {yields} Both endogenous and transfected {delta}ENaC localize with COMMD1 and transferrin suggesting they are located in early/recycling endosomes. -- Abstract: The delta subunit of the epithelial sodium channel ({delta}ENaC) is a member of the ENaC/degenerin family of ion channels. {delta}ENaC is distinct from the related {alpha}-, {beta}- and {gamma}ENaC subunits, known for their role in sodium homeostasis and blood pressure control, as {delta}ENaC is expressed in brain neurons and activated by external protons. COMMD1 (copper metabolism Murr1 domain 1) was previously found to associate with and downregulate {delta}ENaC activity. Here, we show that COMMD1 interacts with {delta}ENaC through its COMM domain. Co-expression of {delta}ENaC with COMMD1 significantly reduced {delta}ENaC surface expression, and led to an increase in {delta}ENaC ubiquitination. Immunocytochemical and confocal microscopy studies show that COMMD1 promoted localization of {delta}ENaC to the early/recycling endosomal pool where the two proteins were localized together. These results suggest that COMMD1 downregulates {delta}ENaC activity by reducing {delta}ENaC surface expression through promoting internalization of surface {delta}ENaC to an intracellular recycling pool, possibly via enhanced ubiquitination.

  6. Future Deltas Utrecht University research focus area: towards sustainable management of sinking deltas

    Science.gov (United States)

    Stouthamer, E.; van Asselen, S.

    2015-11-01

    Deltas are increasingly under pressure from human impact and climate change. To deal with these pressures that threat future delta functioning, we need to understand interactions between physical, biological, chemical and social processes in deltas. This requires an integrated approach, in which knowledge on natural system functioning is combined with knowledge on spatial planning, land and water governance and legislative frameworks. In the research focus area Future Deltas of Utrecht University an interdisciplinary team from different research groups therefore works together. This allows developing integrated sustainable and resilient delta management strategies, which is urgently needed to prevent loss of vital delta services.

  7. Strategic Planning for Electronic Resources Management: A Case Study at Gustavus Adolphus College

    Science.gov (United States)

    Hulseberg, Anna; Monson, Sarah

    2009-01-01

    Electronic resources, the tools we use to manage them, and the needs and expectations of our users are constantly evolving; at the same time, the roles, responsibilities, and workflow of the library staff who manage e-resources are also in flux. Recognizing a need to be more intentional and proactive about how we manage e-resources, the…

  8. REVIEW OF MOODLE PLUGINS FOR DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES FROM LANGUAGE DISCIPLINES

    Directory of Open Access Journals (Sweden)

    Anton M. Avramchuk

    2015-09-01

    Full Text Available Today the problem of designing multimedia electronic educational resources from language disciplines in Moodle is very important. This system has a lot of different, powerful resources, plugins to facilitate the learning of students with language disciplines. This article presents an overview and comparative analysis of the five Moodle plugins for designing multimedia electronic educational resources from language disciplines. There have been considered their key features and functionality in order to choose the best for studying language disciplines in the Moodle. Plugins are compared by a group of experts according to the criteria: efficiency, functionality and easy use. For a comparative analysis of the plugins it is used the analytic hierarchy process.

  9. All Electron ab initio Investigations of the Three Lowest Lying Electronic States of the RuC Molecule

    DEFF Research Database (Denmark)

    Shim, Irene; Gingerich, K. A.

    2000-01-01

    The three lowest-lying electronic states of RuC, (1)Sigma(+), (3)Delta, and (1)Delta, have been investigated by performing all-electron ab initio multi-configuration self-consistent-field (CASSCF) and multi-reference configuration interaction (MRCI) calculations including relativistic corrections....... The electronic ground state is derived as (1)Sigma(+) with the spectroscopic constants r(e) = 1.616 Angstrom and omega(e) = 1085 cm(-1). The lowest-lying excited state, (3)Delta, has r(e) = 1.632 Angstrom, omega(e) = 1063 cm(-1), and T-e = 912 cm(-1). These results are consistent with recent spectroscopic values....... The chemical bonds in all three lowest-lying states are triple bonds composed of one sigma and two pi bonds. (C) 2000 Elsevier Science B.V. All rights reserved....

  10. Integrated Socio-Environmental Assessment of Deltas to Support Strategic Planning and Management

    Science.gov (United States)

    Nicholls, R. J.; Lázár, A. N.; Hutton, C.; Adams, H.; Salehin, M.; Rahman, M. M.

    2016-12-01

    Deltas are some of the most densely populated areas in the world, as exemplified by the coastal zone of Bangladesh which has a rural population densities of >1,000 people/km2. These people's livelihoods and food security are strongly dependent on natural resources which are influenced by multiple drivers. These include climate variability and change, subsidence, upstream river flow modifications, and land use changes such as polderisation and conversion of rice to shrimp production. Hydro-environmental changes, such as saline water intrusion and natural disasters (e.g. river flooding, cyclones and storm surges) have negative impacts that severely affect land use and livelihood opportunities of the coastal population. These changes can be especially detrimental for the well-being of the poorest households that are highly dependent on natural resources. These multiple drivers raise fundamental policy questions about how we might develop the delta over the coming decades. The Delta Dynamic Integrated Emulator (ΔDIEM) model has been developed to examine these interactions between the coupled bio-physical environment and the livelihoods of these poor populations in coastal Bangladesh. ΔDIEM allows the long-term analysis of the possible changes in this system by linking projected changes in physical processes (e.g. river flows, nutrients), with productivity (e.g. fish, rice), social processes (e.g. access, property rights, migration) and governance/management (e.g. fisheries, agriculture, water and land use management). A range of proposed interventions can be simulated. This integrated approach is designed to provide Bangladeshi policy makers with science-based evidence of possible development trajectories within the coastal delta plain over timescales up to 50 years, including comprehensive analysis of their different choices in terms of natural resource conservation, poverty, etc. This presentation will focus on key results and insights from the analysis.

  11. N-Type delta Doping of High-Purity Silicon Imaging Arrays

    Science.gov (United States)

    Blacksberg, Jordana; Hoenk, Michael; Nikzad, Shouleh

    2005-01-01

    A process for n-type (electron-donor) delta doping has shown promise as a means of modifying back-illuminated image detectors made from n-doped high-purity silicon to enable them to detect high-energy photons (ultraviolet and x-rays) and low-energy charged particles (electrons and ions). This process is applicable to imaging detectors of several types, including charge-coupled devices, hybrid devices, and complementary metal oxide/semiconductor detector arrays. Delta doping is so named because its density-vs.-depth characteristic is reminiscent of the Dirac delta function (impulse function): the dopant is highly concentrated in a very thin layer. Preferably, the dopant is concentrated in one or at most two atomic layers in a crystal plane and, therefore, delta doping is also known as atomic-plane doping. The use of doping to enable detection of high-energy photons and low-energy particles was reported in several prior NASA Tech Briefs articles. As described in more detail in those articles, the main benefit afforded by delta doping of a back-illuminated silicon detector is to eliminate a "dead" layer at the back surface of the silicon wherein high-energy photons and low-energy particles are absorbed without detection. An additional benefit is that the delta-doped layer can serve as a back-side electrical contact. Delta doping of p-type silicon detectors is well established. The development of the present process addresses concerns specific to the delta doping of high-purity silicon detectors, which are typically n-type. The present process involves relatively low temperatures, is fully compatible with other processes used to fabricate the detectors, and does not entail interruption of those processes. Indeed, this process can be the last stage in the fabrication of an imaging detector that has, in all other respects, already been fully processed, including metallized. This process includes molecular-beam epitaxy (MBE) for deposition of three layers, including

  12. Modern ICT Tools: Online Electronic Resources Sharing Using Web ...

    African Journals Online (AJOL)

    Modern ICT Tools: Online Electronic Resources Sharing Using Web 2.0 and Its Implications For Library And Information Practice In Nigeria. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more ...

  13. THE MODEL OF LINGUISTIC TEACHERS’ COMPETENCY DEVELOPMENT ON DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES IN THE MOODLE SYSTEM

    Directory of Open Access Journals (Sweden)

    Anton M. Avramchuk

    2017-10-01

    Full Text Available The article is devoted to the problem of developing the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system. The concept of "the competence of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system" is justified and defined. Identified and characterized the components by which the levels of the competency development of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system should be assessed. Developed a model for the development of the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system, which is based on the main scientific approaches, used in adult education, and consists of five blocks: target, informative, technological, diagnostic and effective.

  14. Developing Humanities Collections in the Digital Age: Exploring Humanities Faculty Engagement with Electronic and Print Resources

    Science.gov (United States)

    Kachaluba, Sarah Buck; Brady, Jessica Evans; Critten, Jessica

    2014-01-01

    This article is based on quantitative and qualitative research examining humanities scholars' understandings of the advantages and disadvantages of print versus electronic information resources. It explores how humanities' faculty members at Florida State University (FSU) use print and electronic resources, as well as how they perceive these…

  15. Effect of rare-earth ion size on local electron structure in RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (R = Tm, Dy, Gd, Eu, Nd and Y) superconductors: A positron study

    Energy Technology Data Exchange (ETDEWEB)

    Chen Zhenping [Department of Technology and Physics, Zhengzhou University of Light Industry, 5 Dongfeng Road, Zhengzhou, Henan 450002 (China)]. E-mail: czhping@zzuli.edu.cn; Zhang Jincang [Department of Physics, Shanghai University, Shanghai 200436 (China); Su Yuling [Department of Technology and Physics, Zhengzhou University of Light Industry, 5 Dongfeng Road, Zhengzhou, Henan 450002 (China); Xue Yuncai [Department of Technology and Physics, Zhengzhou University of Light Industry, 5 Dongfeng Road, Zhengzhou, Henan 450002 (China); Cao Shixun [Department of Physics, Shanghai University, Shanghai 200436 (China)

    2006-02-15

    The effects of rare-earth ionic size on the local electron structure, lattice parameters and superconductivity have been investigated by positron annihilation technique (PAT) and related experiments for RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} (R = Tm, Dy, Gd, Eu, Nd and Y) superconductors. The local electron density n {sub e} is evaluated as a function of the rare-earth radius. The results show that both the bulk-lifetime {tau} {sub B} and the defect lifetime {tau} {sub 2} increase with increasing rare-earth ionic radius, while the local electron density n {sub e} decrease with increasing rare-earth ionic radius. These results prove that the changes of n {sub e}, the degree of orthorhombic distortion and the coupling between the Cu-O chains and the CuO{sub 2} planes all have an effect on the superconductivity of RBa{sub 2}Cu{sub 3}O{sub 7-{delta}} systems.

  16. Remote Sensing of River Delta Inundation: Exploiting the Potential of Coarse Spatial Resolution, Temporally-Dense MODIS Time Series

    Directory of Open Access Journals (Sweden)

    Claudia Kuenzer

    2015-07-01

    Full Text Available River deltas belong to the most densely settled places on earth. Although they only account for 5% of the global land surface, over 550 million people live in deltas. These preferred livelihood locations, which feature flat terrain, fertile alluvial soils, access to fluvial and marine resources, a rich wetland biodiversity and other advantages are, however, threatened by numerous internal and external processes. Socio-economic development, urbanization, climate change induced sea level rise, as well as flood pulse changes due to upstream water diversion all lead to changes in these highly dynamic systems. A thorough understanding of a river delta’s general setting and intra-annual as well as long-term dynamic is therefore crucial for an informed management of natural resources. Here, remote sensing can play a key role in analyzing and monitoring these vast areas at a global scale. The goal of this study is to demonstrate the potential of intra-annual time series analyses at dense temporal, but coarse spatial resolution for inundation characterization in five river deltas located in four different countries. Based on 250 m MODIS reflectance data we analyze inundation dynamics in four densely populated Asian river deltas—namely the Yellow River Delta (China, the Mekong Delta (Vietnam, the Irrawaddy Delta (Myanmar, and the Ganges-Brahmaputra (Bangladesh, India—as well as one very contrasting delta: the nearly uninhabited polar Mackenzie Delta Region in northwestern Canada for the complete time span of one year (2013. A complex processing chain of water surface derivation on a daily basis allows the generation of intra-annual time series, which indicate inundation duration in each of the deltas. Our analyses depict distinct inundation patterns within each of the deltas, which can be attributed to processes such as overland flooding, irrigation agriculture, aquaculture, or snowmelt and thermokarst processes. Clear differences between mid

  17. Delta 2.0

    DEFF Research Database (Denmark)

    Skott, Jeppe; Skott, Charlotte Krog; Jess, Kristine

    DELTA 2.0 er en ny og helt opdateret udgave af Delta, der i ti år været brugt i matematiklærernes grund-, efter- og videreuddannelse. DELTA 2.0 er seriens almene fagdidaktik. Der er også fagdidaktiske overvejelser i de øvrige bøger i serien, men de er knyttet til specifikt matematisk indhold. DELTA...... 2.0 behandler mere generelle matematikdidaktiske problemstillinger såsom læringsteoretiske overvejelser i forbindelse med matematik, centrale aspekter af det at undervise i matematik og digitale teknologier som værktøj til at støtte elevers faglige læring af matematik....

  18. Mackenzie Gas Project : gas resource and supply study

    International Nuclear Information System (INIS)

    Harris, D.G.; Braaten, K.M.

    2004-01-01

    A study was conducted to assess the future gas supply for the Mackenzie Gas Project. The economically recoverable gas resources and deliverability in the region were assessed in order to support construction of the Mackenzie Valley pipeline and the associated gathering system. This supply study was based on a 25 year timeframe for resource development. Production forecasts were also prepared for 50 years following the date of the study. Natural gas forecasts for the general area to be served by the proposed pipeline were also presented. This report includes an introduction to the final gas resource and supply study as well as the regional geology relating to discovered and undiscovered resources. The following regions were included in the study area: onshore Mackenzie Delta including the Niglintgak, Parsons Lake and Taglu anchor fields; central Mackenzie Valley region extending from the Mackenzie Delta south to 63 degrees latitude; northern portion of the Yukon Territory; and, portions of the offshore Mackenzie Delta region limited to a water depth of 30 metres. Forecasts and economic analyses were prepared for the following 3 scenarios: contingent onshore resources only; contingent and prospective onshore resources; and, contingent and prospective onshore and offshore resources. Sensitivity forecasts were prepared for a fully expanded pipeline capacity of 1.8 bcf/day with an equal capacity gathering system. In addition, the National Energy Board estimates of resources for the 3 anchor field were used in place of the operator's estimates. A geological review was included for the plays in the study area. 15 refs., 43 tabs., 38 figs

  19. Crude Oil Resource: A Blessing Or Curse To Nigeria – The Case Of ...

    African Journals Online (AJOL)

    Crude Oil Resource: A Blessing Or Curse To Nigeria – The Case Of The Niger Delta. S Tamuno, JM Felix. Abstract. This paper examines the question as to whether crude oil resource is a blessing or curse to Nigeria: The case of the Niger Delta Region. The paper traces the origin of oil exploration and exploitation from ...

  20. Post traumatic stress in the Niger Delta of Nigeria: A qualitative ...

    African Journals Online (AJOL)

    Post traumatic stress in the Niger Delta of Nigeria: A qualitative analysis of narrative of women. ... PROMOTING ACCESS TO AFRICAN RESEARCH ... Keywords: Resource-curse, Post-traumatic Stress disorder (PTSD), Psychosocial ... Rwanda (3); Senegal (6); Sierra Leone (1); South Africa (96); South Sudan (1); Sudan (3) ...

  1. Peat compaction in deltas : implications for Holocene delta evolution

    NARCIS (Netherlands)

    van Asselen, S.

    2010-01-01

    Many deltas contain substantial amounts of peat, which is the most compressible soil type. Therefore, peat compaction potentially leads to high amounts of subsidence in deltas. The main objective of this research was to quantify subsidence due to peat compaction in Holocene fluvial-deltaic settings

  2. Formation of conjugated delta8,delta10-double bonds by delta12-oleic-acid desaturase-related enzymes: biosynthetic origin of calendic acid.

    Science.gov (United States)

    Cahoon, E B; Ripp, K G; Hall, S E; Kinney, A J

    2001-01-26

    Divergent forms of the plant Delta(12)-oleic-acid desaturase (FAD2) have previously been shown to catalyze the formation of acetylenic bonds, epoxy groups, and conjugated Delta(11),Delta(13)-double bonds by modification of an existing Delta(12)-double bond in C(18) fatty acids. Here, we report a class of FAD2-related enzymes that modifies a Delta(9)-double bond to produce the conjugated trans-Delta(8),trans-Delta(10)-double bonds found in calendic acid (18:3Delta(8trans,10trans,12cis)), the major component of the seed oil of Calendula officinalis. Using an expressed sequence tag approach, cDNAs for two closely related FAD2-like enzymes, designated CoFADX-1 and CoFADX-2, were identified from a C. officinalis developing seed cDNA library. The deduced amino acid sequences of these polypeptides share 40-50% identity with those of other FAD2 and FAD2-related enzymes. Expression of either CoFADX-1 or CoFADX-2 in somatic soybean embryos resulted in the production of calendic acid. In embryos expressing CoFADX-2, calendic acid accumulated to as high as 22% (w/w) of the total fatty acids. In addition, expression of CoFADX-1 and CoFADX-2 in Saccharomyces cerevisiae was accompanied by calendic acid accumulation when induced cells were supplied exogenous linoleic acid (18:2Delta(9cis,12cis)). These results are thus consistent with a route of calendic acid synthesis involving modification of the Delta(9)-double bond of linoleic acid. Regiospecificity for Delta(9)-double bonds is unprecedented among FAD2-related enzymes and further expands the functional diversity found in this family of enzymes.

  3. Salinity Impacts on Agriculture and Groundwater in Delta Regions

    Science.gov (United States)

    Clarke, D.; Salehin, M.; Jairuddin, M.; Saleh, A. F. M.; Rahman, M. M.; Parks, K. E.; Haque, M. A.; Lázár, A. N.; Payo, A.

    2015-12-01

    Delta regions are attractive for high intensity agriculture due to the availability of rich sedimentary soils and of fresh water. Many of the world's tropical deltas support high population densities which are reliant on irrigated agriculture. However environmental changes such as sea level rise, tidal inundation and reduced river flows have reduced the quantity and quality of water available for successful agriculture. Additionally, anthropogenic influences such as the over abstraction of ground water and the increased use of low quality water from river inlets has resulted in the accumulation of salts in the soils which diminishes crop productivity. Communities based in these regions are usually reliant on the same water for drinking and cooking because surface water is frequently contaminated by commercial and urban pollution. The expansion of shallow tube well systems for drinking water and agricultural use over the last few decades has resulted in mobilisation of salinity in the coastal and estuarine fringes. Sustainable development in delta regions is becoming constrained by water salinity. However salinity is often studied as an independent issue by specialists working in the fields of agriculture, community water supply and groundwater. The lack of interaction between these disciplines often results in corrective actions being applied to one sector without fully assessing the effects of these actions on other sectors. This paper describes a framework for indentifying the causes and impacts of salinity in delta regions based on the source-pathway-receptor framework. It uses examples and scenarios from the Ganges-Brahmaputra-Meghna delta in Bangladesh together with field measurements and observations made in vulnerable coastal communities. The paper demonstrates the importance of creating an holistic understanding of the development and management of water resources to reduce the impact of salinity in fresh water in delta regions.

  4. Electronic resource management systems a workflow approach

    CERN Document Server

    Anderson, Elsa K

    2014-01-01

    To get to the bottom of a successful approach to Electronic Resource Management (ERM), Anderson interviewed staff at 11 institutions about their ERM implementations. Among her conclusions, presented in this issue of Library Technology Reports, is that grasping the intricacies of your workflow-analyzing each step to reveal the gaps and problems-at the beginning is crucial to selecting and implementing an ERM. Whether the system will be used to fill a gap, aggregate critical data, or replace a tedious manual process, the best solution for your library depends on factors such as your current soft

  5. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Directory of Open Access Journals (Sweden)

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these

  6. The Electron Microscopy Outreach Program: A Web-based resource for research and education.

    Science.gov (United States)

    Sosinsky, G E; Baker, T S; Hand, G; Ellisman, M H

    1999-01-01

    We have developed a centralized World Wide Web (WWW)-based environment that serves as a resource of software tools and expertise for biological electron microscopy. A major focus is molecular electron microscopy, but the site also includes information and links on structural biology at all levels of resolution. This site serves to help integrate or link structural biology techniques in accordance with user needs. The WWW site, called the Electron Microscopy (EM) Outreach Program (URL: http://emoutreach.sdsc.edu), provides scientists with computational and educational tools for their research and edification. In particular, we have set up a centralized resource containing course notes, references, and links to image analysis and three-dimensional reconstruction software for investigators wanting to learn about EM techniques either within or outside of their fields of expertise. Copyright 1999 Academic Press.

  7. Hydrogeochemical and stream sediment reconnaissance basic data for Big Delta Quadrangle, Alaska

    International Nuclear Information System (INIS)

    1981-01-01

    Field and laboratory data are presented for 1380 water samples from the Big Delta Quadrangle, Alaska. The samples were collected by Los Alamos Scientific Laboratory; laboratory analysis and data reporting were performed by the Uranium Resource Evaluation Project at Oak Ridge, Tennessee

  8. Technical Communicator: A New Model for the Electronic Resources Librarian?

    Science.gov (United States)

    Hulseberg, Anna

    2016-01-01

    This article explores whether technical communicator is a useful model for electronic resources (ER) librarians. The fields of ER librarianship and technical communication (TC) originated and continue to develop in relation to evolving technologies. A review of the literature reveals four common themes for ER librarianship and TC. While the…

  9. Inhabiting the Delta: A Landscape Approach to Transformative Socio-Ecological Restoration

    Directory of Open Access Journals (Sweden)

    Brett Milligan

    2017-09-01

    Full Text Available doi: https://doi.org/10.15447/sfews.2017v15iss3art3Current legislation and plans for the Sacramento–San Joaquin Delta (Delta call for large-scale restoration of aquatic and terrestrial habitats, which will require significant changes in waterways, land uses, and cultural patterns. These re-made landscapes will be subject to a variety of new human uses, which Delta planning and adaptive management literature has yet to adequately consider. Failing to account for human uses and evolving place values can lead to diminished performance and public support for Delta restoration efforts. Our empirical study examined restored and naturalized Delta landscapes using an integrative landscape approach that seeks to reconcile multiple goals and land-use agendas that span ecological, social, economic, and political domains. The research design consisted of six overlapping methods that included a planning, policy, and law review specific to the Delta; surveys and interviews with approximately 100 land managers, scientists, land-owners, law-enforcement personnel, agency representatives, and Delta residents; nine case studies of restored and naturalized delta landscapes; GIS mapping; and extensive field work. Findings derived from the synthesis of these methods show that human uses of the Delta’s re-wilded landscapes are diverse and pervasive. Given the infrastructural and urbanized context of the region, these environments are subject to multiple and sometimes conflicting uses, perceptions, and place values. Though these myriad uses cannot be fully predicted or controlled (nor should they be, findings showed that more proactive and inclusive planning for human uses can encourage or discourage particular uses while also building constituency, support, and active engagement in ecological restoration efforts. We conclude that reconciling human uses with ecological recovery in the Delta will require a more localized, multi-functional, and creative approach to

  10. $\\delta$-Expansion at Finite Temperature

    OpenAIRE

    Ramos, Rudnei O.

    1996-01-01

    We apply the $\\delta$-expansion perturbation scheme to the $\\lambda \\phi^{4}$ self-interacting scalar field theory in 3+1 D at finite temperature. In the $\\delta$-expansion the interaction term is written as $\\lambda (\\phi^{2})^{ 1 + \\delta}$ and $\\delta$ is considered as the perturbation parameter. We compute within this perturbative approach the renormalized mass at finite temperature at a finite order in $\\delta$. The results are compared with the usual loop-expansion at finite temperature.

  11. Variation in leaf water delta D and delta 18O values during the evapotranspiration process

    International Nuclear Information System (INIS)

    Leopoldo, P.R.; Foloni, L.L.

    1984-01-01

    A theoretical model was developed to evaluate leaf water delta D and delta 18 O variation in relation to: leaf temperature, relative humidity converted to leaf temperature and delta D and delta 18 O values of atmospheric water vapour and soil water. (M.A.C.) [pt

  12. Rise and Fall of one of World's largest deltas; the Mekong delta in Vietnam

    Science.gov (United States)

    Minderhoud, P. S. J.; Eslami Arab, S.; Pham, H. V.; Erkens, G.; van der Vegt, M.; Oude Essink, G.; Stouthamer, E.; Hoekstra, P.

    2017-12-01

    The Mekong delta is the third's largest delta in the world. It is home to almost 20 million people and an important region for the food security in South East Asia. As most deltas, the Mekong delta is the dynamic result of a balance of sediment supply, sea level rise and subsidence, hosting a system of fresh and salt water dynamics. Ongoing urbanization, industrialization and intensification of agricultural practices in the delta, during the past decades, resulted in growing domestic, agricultural and industrial demands, and have led to a dramatic increase of fresh water use. Since the year 2000, the amount of fresh groundwater extracted from the subsurface increased by 500%. This accelerated delta subsidence as the groundwater system compacts, with current sinking rates exceeding global sea level rise up to an order of magnitude. These high sinking rates have greatly altered the sediment budget of the delta and, with over 50% of the Mekong delta surface elevated less than 1 meter above sea level, greatly increase vulnerability to flooding and storm surges and ultimately, permanent inundation. Furthermore, as the increasingly larger extractions rapidly reduce the fresh groundwater reserves, groundwater salinization subsequently increases. On top of that, dry season low-flows by the Mekong river cause record salt water intrusion in the delta's estuarine system, creating major problems for rice irrigation. We present the work of three years research by the Dutch-Vietnamese `Rise and Fall' project on land subsidence and salinization in both groundwater and surface water in the Vietnamese Mekong delta.

  13. MODEL OF AN ELECTRONIC EDUCATIONAL RESOURCE OF NEW GENERATION

    Directory of Open Access Journals (Sweden)

    Anatoliy V. Loban

    2016-01-01

    Full Text Available The mathematical structure of the modular architecture of an electronic educational resource (EER of new generation, which allows to decompose the process of studying the subjects of the course at a hierarchically ordered set of data (knowledge and procedures for manipulating them, to determine the roles of participants of process of training of and technology the development and use of EOR in the study procrate.

  14. Losing ground in mega-deltas: basin-scale response to existential threats to the Mekong Delta

    Science.gov (United States)

    Arias, M. E.; Kondolf, G. M.; Schmitt, R. J. P.; Carling, P. A.; Darby, S. E.; Bizzi, S.; Castelletti, A.; Cochrane, T. A.; Gibson, S.; Kummu, M.; Oeurng, C.; Rubin, Z.; Wild, T. B.

    2017-12-01

    The Mekong Delta is, in terms of the number of livelihoods it supports, its economic importance, and in its vulnerability to climate change and sinking lands, one of the world's critically threatened mega-deltas. Livelihoods depend on the mere existence of the delta, but also on ecosystem services provided by the delta's drainage basin spanning 795,000 km2 in six abutting countries. These ecosystem services include delivery of sand required to build delta land in the face of rising sea-levels and sediment bound nutrients, provision of spawning habitat for fish that are ultimately harvested in the delta, and hydrologic regulation driving the delta's unique flood-pulse regime. However, while the delta is mainly located in Vietnam, the basin of the Mekong River is shared among China, Myanmar, Laos, Thailand, Cambodia, and Vietnam. In the context of the region's dynamic growth, individual countries are pushing their own development agendas, which include extensive dam building, in-channel sand mining, construction of dykes and canals, and groundwater pumping, all of which contribute to subsidence and erosion of the Delta. Our synthesis of recent research indicates that most of the Mekong's delta land will likely fall below sea-level by 2100 as result of these drivers, exacerbating the impacts of global climatic changes. In this context, local infrastructural projects and changes in land- and water-management may temporarily mitigate some negative effects, but do not address the existential threat to the delta as a whole. To prevent, or at least substantially postpone, the drowning of the Mekong Delta requires identification of the key drivers and immediate concerted management actions on the basin-scale to change the trajectory of subsidence and sediment deficit. A specific challenge is to find the institutional arrangements in this transnational context that could support the needed management changes and equitably distribute costs and impacts. The Mekong Delta is

  15. Hepatitis delta genotypes in chronic delta infection in the northeast of Spain (Catalonia).

    Science.gov (United States)

    Cotrina, M; Buti, M; Jardi, R; Quer, J; Rodriguez, F; Pascual, C; Esteban, R; Guardia, J

    1998-06-01

    Based on genetic analysis of variants obtained around the world, three genotypes of the hepatitis delta virus have been defined. Hepatitis delta virus variants have been associated with different disease patterns and geographic distributions. To determine the prevalence of hepatitis delta virus genotypes in the northeast of Spain (Catalonia) and the correlation with transmission routes and clinical disease, we studied the nucleotide divergence of the consensus sequence of HDV RNA obtained from 33 patients with chronic delta hepatitis (24 were intravenous drug users and nine had no risk factors), and four patients with acute self-limited delta infection. Serum HDV RNA was amplified by the polymerase chain reaction technique and a fragment of 350 nucleotides (nt 910 to 1259) was directly sequenced. Genetic analysis of the nucleotide consensus sequence obtained showed a high degree of conservation among sequences (93% of mean). Comparison of these sequences with those derived from different geographic areas and pertaining to genotypes I, II and III, showed a mean sequence identity of 92% with genotype I, 73% with genotype II and 61% with genotype III. At the amino acid level (aa 115 to 214), the mean identity was 87% with genotype I, 63% with genotype II and 56% with genotype III. Conserved regions included the RNA editing domain, the carboxyl terminal 19 amino acids of the hepatitis delta antigen and the polyadenylation signal of the viral mRNA. Hepatitis delta virus isolates in the northeast of Spain are exclusively genotype I, independently of the transmission route and the type of infection. No hepatitis delta virus subgenotypes were found, suggesting that the origin of hepatitis delta virus infection in our geographical area is homogeneous.

  16. Sharing Remote and Local Information for Tracking Spring Breakup in the Mackenzie Delta and Beaufort Sea

    Science.gov (United States)

    Forbes, D. L.; Whalen, D.; Fraser, P.

    2015-12-01

    The Mackenzie Delta is the second largest on the Arctic Ocean, covering 13 000 km2. The annual flood regime in the delta is dominated by the spring snowmelt freshet and associated ice breakup, as water from the south arrives in the ice-covered delta and spreads over bottomfast and adjacent floating sea ice at the delta front. The complex processes of water-ice interaction, flow partitioning, and overbank flooding to replenish waters in 43 000 delta lakes threaten community, transportation, subsistence, and energy infrastructure in the delta. The annual breakup season is a time of rejuvenation, excitement, and anxiety for delta residents and stakeholders. To track the progress of breakup and meet the need for knowledge dissemination to the local communities, a Mackenzie-Beaufort breakup newsletter has been produced by Natural Resources Canada on a quasi-daily basis during the May-June spring flood season for 10 years, and distributed to an e-mail list that grew to over 300 subscribers. This provides near real-time tracking of water levels and breakup using on-line gauges (Environment Canada), daily MODIS satellite imagery (NASA), Landsat imagery (USGS) and intermittent radar imagery (various sources). In earlier years, information was also supplied from field programs operating in the delta during breakup, but changing priorities and funding have reduced the number of outside researchers present during these critical weeks. Meanwhile the number of local contributors has grown, providing observations and photographs to share with the local, regional and global readership. In this way the newsletter evolved into a two-way communication tool and community portal. The newsletter is a chronicle of each breakup season and a key resource for territorial and municipal managers, subsistence organizations, and emergency response agencies, with routine requests for specific imagery in areas of concern. With the completion of 10 years under the present model, we are exploring

  17. Deltas on the move. Making deltas cope with the effects of climate change

    International Nuclear Information System (INIS)

    Reker, J.; Van Winden, A.; Braakhekke, W.; Vermaat, J.; Eleveld, M.; Janssen, R.; De Reus, N.; Omzigt, N.

    2006-01-01

    This scoping study is the first phase of a study aimed at: (a) providing knowledge on the potential of a system-based approach to deal with the effects of climate change as an alternative for the more traditional technical measures such as dams, dikes and surge barriers. This should be shown for both rich and poor countries and should address hydrological, ecological as well as socio-economic aspects; and (b) identifying the potential to market these results worldwide. To reach these objectives four research steps are defined: (1) to make an inventory of deltas: their vulnerability to the effects of climate change; (2) development of indicators for successful use of a system-based approach; (3) to provide an overview of the potential of soft measures for these deltas; (4) to select a number of deltas with potential for marketing system-based measures and the development of strategies to link economic and ecological objectives. This scoping study addresses step 1 only. The results from step 1 will be used as a starting point for steps 2 and 3. The outputs of this scoping study are threefold: a background report (this report); a flyer with a brief description of the findings; a website with information on delta's and how these may be affected by climate change. The scoping study will roughly outline which deltas are still functioning in a more or less natural manner - or could be (re)developed in that direction - and thus would be good candidates for a system-based approach. Chapter 2 gives a description of the geomorphological and ecological processes in a delta. In addition, those aspects of climate change that can have an effect on deltas are described. The third chapter deals with human interventions in deltas and whether or not they fit within a system-based approach. In a system-based approach, as presented in Chapter 4, natural processes are given free reign where possible. Chapter 5 shows how available data on deltas could be used in such a system

  18. Economic Costs and Adaptations for Alternative Regulations of California's Sacramento–San Joaquin Delta

    Directory of Open Access Journals (Sweden)

    Stacy K. Tanaka

    2011-07-01

    Full Text Available Stacy K. Tanaka, Christina R. Connell–Buck, Kaveh Madani, Josue Medellín-Azuara, Jay R. Lund, and Ellen Hanakdoi: http://dx.doi.org/10.15447/sfews.2014v9iss2art4Water exports from California’s Sacramento–San Joaquin Delta are an environmental concern because they reduce net outflows of fresh water from the Delta, and can entrain fish and disrupt flows within the Delta. If exports were no longer pumped from within the Delta, the regulatory issue becomes one of maintaining appropriate flows into and out of the Delta. This paper presents the results of two sets of hydro-economic optimization modeling runs, which were developed to represent a range of modified Delta operations and their economic and operational effects on California’s water supply system. The first set of runs represents decreasing export capacity from the Delta. The second set increases minimum net Delta outflow (MNDO requirements. The hydro-economic model seeks the least–cost statewide water management scheme for water supply, including a wide range of resources and water management options. Results show that reducing exports or increasing MNDO requirements increase annual average statewide water scarcity, scarcity costs, and operating costs (from greater use of desalination, wastewater recycling, water treatment, and pumping. Effects of reduced exports are especially concentrated in agricultural communities in the southern Central Valley because of their loss of access to overall water supply exports and their ability to transfer remaining water to southern California. Increased outflow requirements increase water scarcity and associated costs throughout California. For an equivalent amount of average Delta outflows, statewide costs increase more rapidly when exports alone are reduced than when minimum outflow requirements are increased and effects are more widely distributed statewide.

  19. Secondary electron yields of carbon-coated and polished stainless steel

    International Nuclear Information System (INIS)

    Ruzic, D.; Moore, R.; Manos, D.; Cohen, S.

    1982-01-01

    To increase the power throughput to a plasma of an existing lower hybrid waveguide, secondary electron production on the walls and subsequent electron multiplication must be reduced. Since carbon has a low secondary electron coefficient (delta), measurements were performed for several UHV compatible carbon coatings (Aquadag/sup X/, vacuum pyrolyzed Glyptal/sup X/, and lamp black deposited by electrophoresis) as a function of primary beam voltage (35 eV to 10 keV), surface roughness (60 through 600 grit mechanical polishing and electropolishing), coating thickness, and angle of incidence (theta). Also measured were uncoated stainless steel, Mo, Cu, Ti, TiC, and ATJ graphite. The yields were obtained by varying the sample bias and measuring the collected current while the samples were in the electron beam of a scanning Auger microprobe. This technique allows delta measurements of Auger characterized surfaces with < or =0.3 mm spatial resolution. Results show delta to have a typical energy dependence, with a peak occurring at 200 to 300 eV for normal incidence, and at higher energy for larger theta. In general, delta increases with theta more for smooth surfaces than for rough ones. Ninety percent of the secondary electrons have energies less than 25 eV. Some carbonized coating and surface treatment combinations give delta/sub max/ = 0.88 +- 0.01 for normal electron beam incidence: a reduction of almost 40% compared to untreated stainless steel

  20. Study of 4f hybridization in CeNiX with X=Sn{sub d}eltaGe{sub 1-d}elta, 0<=delta<=1

    Energy Technology Data Exchange (ETDEWEB)

    Fuente, C. de la, E-mail: cesar@unizar.e [Depto. Fisica de la Materia Condensada, Laboratorio de Magnetismo, Universidad de Zaragoza and ICMA-CSIC (Spain); Moral, A. del [Depto. Fisica de la Materia Condensada, Laboratorio de Magnetismo, Universidad de Zaragoza and ICMA-CSIC (Spain); Adroja, D.T. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX (United Kingdom); Fraile, A. [Depto. Fisica de la Materia Condensada, Laboratorio de Magnetismo, Universidad de Zaragoza and ICMA-CSIC (Spain); Arnaudas, J.I. [Instituto de Nanociencia de Aragon, Universidad de Zaragoza (Spain)

    2010-05-15

    We report inelastic neutron scattering and core-level X-ray photoemission spectroscopy experiments for studying the Kondo problem in the CeNiX, X=Sn{sub d}eltaGe{sub 1-d}elta 0<=delta<=1 series. The neutron results confirm that they behave like a Kondo lattice for delta>=0.85, showing broad maxima at around 30 meV, typical of a crystal field magnetic scattering. So, the Ge doping could produce the suppression of the cerium magnetism observed for delta<=0.25. To open a more deep sight on this point, we have analyzed the 3d core-level XPS spectra by using the well-known Gunnarsson-Schoenhammer model. From this analysis, we have obtained the 'on-site' Coulomb bare repulsion for f states, U, and hybridization parameter, DELTA, related with the hopping from the f states to the conduction ones. These U values are very similar for all compounds, about 7 eV, but the hybridization parameter slightly changes from 0.2 to 0.16 eV on increasing the Sn concentration. In Sn-rich compounds, the 4f occupation is close to spin limit fluctuation, which allows us to obtain an estimation of the Kondo temperatures, approx1200 K, and the static 0 K susceptibility, approx1.1x10{sup -3} emu/mol. Finally, we have done 'ab-initio' calculations based on the LDA+U+SO which confirm the existence of a small electronic gap opening in the DOS of Ge-rich compounds for U values lower than 7 eV.

  1. In vivo metabolism of the methyl homologues of delta-8-tetrahydrocannabinol, delta-9-tetrahydrocannabinol and abn-delta-8-tetrahydrocannabinol in the mouse.

    Science.gov (United States)

    Brown, N K; Harvey, D J

    1988-04-01

    Methyl-delta-8-tetrahydrocannabinol (methyl-delta-8-THC), methyl-delta-9-THC and abn-methyl-delta-8-THC were synthesized by condensation of orcinol and (1S)-cis-verbenol and were administered to male Charles River CD-1 mice. Extracted hepatic metabolites were isolated by chromatography on Sephadex LH-20 and examined by gas chromatography/mass spectrometry as trimethylsilyl (TMS), (2H9)TMS and methyl ester/TMS derivatives. In addition, metabolic fractions were reduced with lithium aluminium deuteride to convert carboxylic acids to alcohols for structural correlation. Metabolites from methyl-delta-8-THC were similar with respect to the positions substituted to those produced by higher homologues; the major metabolite was methyl-delta-8-THC-11-oic acid. abn-Methyl-delta-8-THC was metabolized in a different manner. The location of the aromatic methyl group at the position adjacent to ring fusion appeared to inhibit metabolism at C(11) to a considerable extent and also to reduce the amount of the resulting alcohol from being oxidized to a carboxylic acid. This caused other metabolic pathways to become dominant, with the result that a compound containing a hydroxy group at the gem-methyl position was the major metabolite. Hydroxylation at this position has not been confirmed with any other cannabinoid, although it is thought to result in trace concentrations of hydroxy metabolites from some compounds. Metabolism of methyl-delta-9-THC was also similar to that of the higher homologues, with the exception that less metabolism occurred at C(8) and a higher percentage of the total metabolic fraction was accounted for by the 11-oic acid metabolite. Minor metabolites were mainly dihydroxy compounds and hydroxylated derivatives of delta-9-THC-11-oic acid.

  2. Future hydrological alterations in the Mekong Delta under the impact of water resources development, land subsidence and sea level rise

    Directory of Open Access Journals (Sweden)

    Thanh Duc Dang

    2018-02-01

    New hydrological insights for the region: Depending on hydrological characteristics of each region (river-dominated, transitional or tidal, the influence of each potential driver may vary. The operation of proposed hydropower dams would change river-dominated upper floodplain’s water levels by 26 to 70% and −0.8 to −5.9% in the dry and wet season respectively, but the impact diminishes throughout the floodplains. In the wet season, the upper Vietnamese Delta changes from a transitional stage to a river-dominated stage, and localized water infrastructure development in the upper delta has the greatest effect on water levels in the region. Land subsidence combined with sea level rise could have the greatest future influence on flooding in the delta if current rates are extrapolated. Sustainable water management strategies are thus necessary to mitigate changes in the floodplains and delta and increase resilience to sea level rise and land subsidence.

  3. Management of water resources to control groundwater levels in the southern area of the western Nile delta, Egypt

    Directory of Open Access Journals (Sweden)

    Mohamed M. Sobeih

    2017-10-01

    Full Text Available The present study was initiated with the objective of simulating and predicting the effect of future development on the groundwater flow and levels. This supports applications for future planning and wise management of water resources. The study area extends south of El Nubariya canal including Sadat City area and its vicinities in the western Nile delta region. A numerical groundwater flow model (MODFLOW has been employed to simulate flow and get the budget of groundwater in the study area. The model showed that about 28,101,041 m3/day of surface water is infiltrated to groundwater dominantly from canals and excess irrigation water. About the same quantity (28,101,052 m3/day, is discharged from groundwater through production wells, open drains and through some reaches of canals. Three development scenarios were simulated to give predictions of the impact of future increasing recharge, construction of new canal and new open drains, and also increased pumping on the groundwater levels in the study area.

  4. Phenotypic expressions of CCR5-Delta 32/Delta 32 homozygosity

    NARCIS (Netherlands)

    Nguyen, GT; Carrington, M; Beeler, JA; Dean, M; Aledort, LM; Blatt, PM; Cohen, AR; DiMichele, D; Eyster, ME; Kessler, CM; Konkle, B; Leissinger, C; Luban, N; O'Brien, SJ; Goedert, JJ; O'Brien, TR

    1999-01-01

    Objective: As blockade of CC-chemokine receptor 5 (CCR5) has been proposed as therapy for HIV-1, we examined whether the CCR5-Delta 32/Delta 32 homozygous genotype has phenotypic expressions other than those related to HIV-1. Design: Study subjects were white homosexual men or men with hemophilia

  5. The Undiscovered Country: How Many Low-Delta-V Near-Earth Objects Remain to be Found?

    Science.gov (United States)

    Elvis, Martin; Ranjan, Sukrit; Galache, Jose Luis

    2014-11-01

    Low delta-v near-Earth objects (NEOs) are of great interest as targets for science and human missions, for possible retrieval to cis-lunar space and as potential resource targets for both exploration and commercial uses. This interest stems from the exponential nature of the rocket equation that imposes a harsh mass penalty on any mission to a higher delta-v. We have compared the known NEO population from the IAU Minor Planet Center (MPC) with the NEOSSat-1 model residence times for the NEO population (Greenstreet & Gladman, 2012) to assess how many undiscovered NEOs there are as a function of H magnitude and delta-v. We find that the median of known NEOs is at lower delta-v (7.3 km/s) than the model population (9.8 km/s), suggesting a bias toward detecting lower delta-v NEOs. To the precision of our data, which is as low as 40% for the 300-500 m diameter (D) objects, the bulk of the larger D>300 m NEOs have been found from delta-v<10.3 km/s. However in the 50 < D < 300 m range there are tens of thousands of delta-v < 10.3 km/s to be found. We examine the total number of undiscovered NEOs as a function of delta-v and find that to find at least 100 now unknown NEOs requires a threshold delta-v of 5.7 km/s, while to find at least 1000 of them requires a threshold delta-v of 6.2 km/s. These numbers can be used to determine mission delta-v requirements for a given number of suitable targets, that will likely be restricted by other criteria (size, composition, spin state) to a few percent of the total population.

  6. Migration in Deltas: An Integrated Analysis

    Science.gov (United States)

    Nicholls, Robert J.; Hutton, Craig W.; Lazar, Attila; Adger, W. Neil; Allan, Andrew; Arto, Inaki; Vincent, Katharine; Rahman, Munsur; Salehin, Mashfiqus; Sugata, Hazra; Ghosh, Tuhin; Codjoe, Sam; Appeaning-Addo, Kwasi

    2017-04-01

    Deltas and low-lying coastal regions have long been perceived as vulnerable to global sea-level rise, with the potential for mass displacement of exposed populations. The assumption of mass displacement of populations in deltas requires a comprehensive reassessment in the light of present and future migration in deltas, including the potential role of adaptation to influence these decisions. At present, deltas are subject to multiple drivers of environmental change and often have high population densities as they are accessible and productive ecosystems. Climate change, catchment management, subsidence and land cover change drive environmental change across all deltas. Populations in deltas are also highly mobile, with significant urbanization trends and the growth of large cities and mega-cities within or adjacent to deltas across Asia and Africa. Such migration is driven primarily by economic opportunity, yet environmental change in general, and climate change in particular, are likely to play an increasing direct and indirect role in future migration trends. The policy challenges centre on the role of migration within regional adaptation strategies to climate change; the protection of vulnerable populations; and the future of urban settlements within deltas. This paper reviews current knowledge on migration and adaptation to environmental change to discern specific issues pertinent to delta regions. It develops a new integrated methodology to assess present and future migration in deltas using the Volta delta in Ghana, Mahanadi delta in India and Ganges-Brahmaputra-Meghna delta across India and Bangladesh. The integrated method focuses on: biophysical changes and spatial distribution of vulnerability; demographic changes and migration decision-making using multiple methods and data; macro-economic trends and scenarios in the deltas; and the policies and governance structures that constrain and enable adaptation. The analysis is facilitated by a range of

  7. DEVELOPMENT ELECTRONIC MAPS OF ECOLOGICAL STATUS OF WATER OBJECTS OF THE VOLGA RIVER DELTA

    Directory of Open Access Journals (Sweden)

    Z. N. Isenalieva

    2016-01-01

    Full Text Available Abstract. Aim. The aim of this work was the comprehensive study of the ecological state of water objects of the Volga River delta. Methods. The following methods were used: field (collection, observation, organoleptic, uniform chemical analysis techniques are based on colorimetric, settlement, photometric, spectrometric measurement methods. Results. On the basis of results of researches for 2010-2014 performed a comparative analysis of the dynamics of the content of hydro-chemical indicators of environmental quality in waters of the Volga River delta and the residential areas of the background. Applying an integrated approach to the study of biological indicators of water quality. Created digitized map of the quality of aquatic ecosystems of the Volga River delta. Displaying modern ecological condition of watercourses investigated, determined the degree of contamination, the overall trophic and saprobic. Main conclusions. The work has identified adverse environmental situation in water objects of the Astrakhan and the surrounding areas. Average annual concentrations of toxicological substances water objects in the background zone 10 times less than in the water objects of settlements. As a result of work on the basis of ArcGis 10.2.2 created information environment "Eco-monitor", which is a systematic set of information, and quantitatively characterizing the ecological status of water objects. Created on the basis of ArcGis 10.2.2 information environment monitoring system of waterways allows for a temporary and spatial analysis, to assess the quality of different streams in the control sections.

  8. On the origins of hypersaline groundwater in the Nile Delta Aquifer

    Science.gov (United States)

    van Engelen, Joeri; Oude Essink, Gualbert H. P.; Kooi, Henk; Bierkens, Marc F. P.

    2017-04-01

    The fresh groundwater resources in the Nile Delta, Egypt, are of eminent socio-economic importance. These resources are under major stress due to population growth, the anticipated sea level rise and increased groundwater extraction rates, making fresh water availability the most challenging issue in this area. Up till now, numerous groundwater studies mainly focused on sea water intrusion on the top 100m of the groundwater system and assumed salinities not exceeding that of Mediterranean sea water, as there was no knowledge on groundwater in the deeper coastal parts of the Quaternary Nile Delta aquifer (that ranges up to 1000m depth). Recently, however, the Egyptian Research Institute for Groundwater (RIGW) collected salinity measurements and found a widespread occurrence of "hypersaline" groundwater: groundwater with salinities largely exceeding that of sea water at 600m depth (Nofal et al., 2015). This hypersaline groundwater greatly influences flow patterns and the fresh water potential of the aquifer. This research focuses on the origins of the hypersaline groundwater and the possible processes causing its transport. We consider all relevant salinization processes in the Nile Delta aquifer, over a time domain of up to 2.5 million years, which is the time span in which the aquifer got deposited. The following hypotheses were investigated with a combination of analytical solutions and numerical modelling: upward salt transport due to a) molecular diffusion, b) thermal buoyancy, c) consolidation-induced advection and dispersion, or downward transport due to d) composition buoyancy (salt inversion). We conclude that hypotheses a) and b) can be rejected, but c) and d) are both possible with the available information. An enhanced chemical analysis is suggested for further research, to determine the origins of this hypersaline water. This information in combination with the conclusions drawn in this research will give more insight in the potential amount of non

  9. Interplay between barrier width and height in electron tunneling: photoinduced electron transfer in porphyrin-based donor-bridge-acceptor systems.

    Science.gov (United States)

    Pettersson, Karin; Wiberg, Joanna; Ljungdahl, Thomas; Mårtensson, Jerker; Albinsson, Bo

    2006-01-12

    The rate of electron tunneling in molecular donor-bridge-acceptor (D-B-A) systems is determined both by the tunneling barrier width and height, that is, both by the distance between the donor and acceptor as well as by the energy gap between the donor and bridge moieties. These factors are therefore important to control when designing functional electron transfer systems, such as constructs for photovoltaics, artificial photosynthesis, and molecular scale electronics. In this paper we have investigated a set of D-B-A systems in which the distance and the energy difference between the donor and bridge states (DeltaEDB) are systematically varied. Zinc(II) and gold(III) porphyrins were chosen as electron donor and acceptor because of their suitable driving force for photoinduced electron transfer (-0.9 eV in butyronitrile) and well-characterized photophysics. We have previously shown, in accordance with the superexchange mechanism for electron transfer, that the electron transfer rate is proportional to the inverse of DeltaEDB in a series of zinc/gold porphyrin D-B-A systems with bridges of constant edge to edge distance (19.6 A) and varying DeltaEDB (3900-17 600 cm(-1)). Here, we use the same donor and acceptor but the bridge is shortened or extended giving a set of oligo-p-phenyleneethynylene bridges (OPE) with four different edge to edge distances ranging from 12.7 to 33.4 A. These two sets of D-B-A systems-ZnP-RB-AuP+ and ZnP-nB-AuP+-have one bridge in common, and hence, for the first time both the distance and DeltaEDB dependence of electron transfer can be studied simultaneously in a systematic way.

  10. Collaborative Innovation Research on High-tech Industry in the Center Delta

    Directory of Open Access Journals (Sweden)

    Yan Jingdong

    2017-01-01

    Full Text Available As a strong point in the Middle Rises Strategy, the Center Delta is of great significance to high-tech industry development. While the collaborative innovation is an effective way to promote the coordinated development of regional economy. This article selected electronic and communication equipment manufacturing industry of 3 provinces in the Center Delta as samples, built evaluation index system of collaborative innovation of high-tech industry, and put the relevant data into the system coordination degree model, in order to get the synergy of industrial innovation system and innovation environment system of 3 provinces. The empirical results shown that the industrial innovation system and innovation environment system coordination degree of Hubei province was the highest, while Jiangxi province was the lowest. Based on the empirical result analysis of the above-mentioned systems, this article put forward suggestions to promote the development of the high-tech industry collaborative innovation in the Center Delta.

  11. Accurate measurement of electron beam polarization using Compton effect at TJNAF for the experiments G{sup p}{sub E} and N-{delta}; Mesure precise de la polarisation du faisceau d'electrons a TJNAF par polarimetrie compton pour les experiences G{sup p}{sub E} et N-{delta}

    Energy Technology Data Exchange (ETDEWEB)

    Escoffier, St

    2001-10-01

    This work deals with electron beam polarization measurements using Compton effect at TJNAF, for experiments of the proton electromagnetic form factors measurement and for nucleon response functions determination in the pion electroproduction reaction near the {delta}(1232) region. The Compton polarimeter, whose principle is built on elastic electron-photon scattering, was designed and built around a high finesse Fabry-Perot cavity (finesse = 25000). The incident Nd:YAG laser power is amplified by an optical cavity which provides a luminosity such as the statistical uncertainty on the electron polarization measurement is at the level of 1% in one hour. Using Pound-Drever method, laser frequency is locked on one of interferometer resonance frequencies. Circularly photon polarization inside the optical cavity was measured to be 99.6+/-0.45%. The electron beam polarization is deduced from the measurements of the photon polarization, experimental asymmetry and analysing power of our detector. The analysing power is determined by a measurement of the response function of the photon detector, composed of 25 PbWO{sub 4} crystals, thanks to coincidence events detected with the electron detector made up of 4 plans of 48 silicon strips. Measurement uncertainties come meanly from detector's response function modelling, pile up effect and photon beam polarization. Total relative uncertainty on the electron beam polarization measurement is about 1.4% for 40 minutes data taking. Moreover, the Compton polarimeter allows to estimate the electron helicity difference between two polarization reversals. This effect was found compatible with zero at 0.3%. (author)

  12. An Overview of Multi-Dimensional Models of the Sacramento–San Joaquin Delta

    Directory of Open Access Journals (Sweden)

    Michael L. MacWilliams

    2016-12-01

    Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art2Over the past 15 years, the development and application of multi-dimensional hydrodynamic models in San Francisco Bay and the Sacramento–San Joaquin Delta has transformed our ability to analyze and understand the underlying physics of the system. Initial applications of three-dimensional models focused primarily on salt intrusion, and provided a valuable resource for investigating how sea level rise and levee failures in the Delta could influence water quality in the Delta under future conditions. However, multi-dimensional models have also provided significant insights into some of the fundamental biological relationships that have shaped our thinking about the system by exploring the relationship among X2, flow, fish abundance, and the low salinity zone. Through the coupling of multi-dimensional models with wind wave and sediment transport models, it has been possible to move beyond salinity to understand how large-scale changes to the system are likely to affect sediment dynamics, and to assess the potential effects on species that rely on turbidity for habitat. Lastly, the coupling of multi-dimensional hydrodynamic models with particle tracking models has led to advances in our thinking about residence time, the retention of food organisms in the estuary, the effect of south Delta exports on larval entrainment, and the pathways and behaviors of salmonids that travel through the Delta. This paper provides an overview of these recent advances and how they have increased our understanding of the distribution and movement of fish and food organisms. The applications presented serve as a guide to the current state of the science of Delta modeling and provide examples of how we can use multi-dimensional models to predict how future Delta conditions will affect both fish and water supply.

  13. GUIDELINES FOR EVALUATION OF PSYCHOLOGICAL AND PEDAGOGICAL QUALITY CHARACTERISTICS OF ELECTRONIC EDUCATIONAL RESOURCES

    Directory of Open Access Journals (Sweden)

    Galina P. Lavrentieva

    2014-05-01

    Full Text Available The article highlights the causes of insufficient effective use of electronic learning resources and sets out the guidelines on ways to solve the aforementioned problems. The set of didactic, methodical, psychological, pedagogical, design and ergonomic quality requirements is considered for evaluation, selection and application of information and communication technologies in the educational process. The most appropriate mechanisms for the ICT introduction into the learning process are disclosed as it should meet the specific learning needs of the student and the objectives of the educational process. The guidance for psycho-educational assessment of quality of electronic educational resources is provided. It is argued that the effectiveness of the ICT use is to be improved by means of quality evaluation mechanisms involved into the educational process.

  14. Availability, Use and Constraints to Use of Electronic Information Resources by Postgraduates Students at the University of Ibadan

    Directory of Open Access Journals (Sweden)

    Dare Samuel Adeleke

    2017-12-01

    Full Text Available Availability, awareness and use of electronic resources provide access to authoritative, reliable, accurate and timely access to information. The use of electronic information resources (EIRs can enable innovation in teaching and increase timeliness in research of postgraduate students which will eventual result into encouragement of the expected research-led enquiry in this digital age. The study adopted a descriptive survey design. Samples of 300 of postgraduate students within seven out 13 Faculties were randomly selected. Data were collected using questionnaire designed to elicit response from respondents and data were analyzed using descriptive statistics methods percentages, mean, and standard deviation. Results indicated that internet was ranked most available and used in the university. Low level of usage of electronic resources, in particular, full texts data bases is linked to a number of constraints: Interrupted power supply was ranked highest among other factors as speed and capacity of computers, retrieval of records with high recall and low precision, retrieving records relevant to information need, lack of knowledge of search techniques to retrieve information effectively, non possession of requisite IT skills and problems accessing the internet. The study recommended that usage of electronic resources be made compulsory, intensifying awareness campaigns concerning the availability, training on use of electronic resources and the problem of power outage be addressed.

  15. Mystery of the delta(980)

    International Nuclear Information System (INIS)

    Cahn, R.N.; Landshoff, P.V.

    1986-01-01

    The apparent conflict between the dominance of the decay delta->etaπ in D->deltaπ and its absence in iota->deltaπ is analyzed. Explicit models are presented in which the nearby Kanti K threshold plays an important role in resolving the conflict. (orig.)

  16. Niger Delta Development Commission and Sustainable ...

    African Journals Online (AJOL)

    Niger Delta Development Commission and Sustainable Development of Niger Delta Region of Nigeria: The Case of Rivers State. Goddey Wilson. Abstract. The study is on Niger Delta Development Commission and sustainable development of Niger Delta region of Nigeria, the case of Rivers State. The main objective of the ...

  17. Deep Impact Delta II Launch Vehicle Cracked Thick Film Coating on Electronic Packages Technical Consultation Report

    Science.gov (United States)

    Cameron, Kenneth D.; Kichak, Robert A.; Piascik, Robert S.; Leidecker, Henning W.; Wilson, Timmy R.

    2009-01-01

    The Deep Impact spacecraft was launched on a Boeing Delta II rocket from Cape Canaveral Air Force Station (CCAFS) on January 12, 2005. Prior to the launch, the Director of the Office of Safety and Mission Assurance (OS&MA) requested the NASA Engineering and Safety Center (NESC) lead a team to render an independent opinion on the rationale for flight and the risk code assignments for the hazard of cracked Thick Film Assemblies (TFAs) in the E-packages of the Delta II launch vehicle for the Deep Impact Mission. The results of the evaluation are contained in this report.

  18. Photoreflectance study of InAs ultrathin layer embedded in Si-delta-doped GaAs/AlGaAs quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Dhifallah, I., E-mail: ines.dhifallah@gmail.co [Laboratoire de Photovoltaique, des Semiconducteurs et des Nanostructures, Centre de Recherche et des Technologies de l' energie, BP 95 Hammam-Lif 2050 (Tunisia); Daoudi, M.; Bardaoui, A. [Laboratoire de Photovoltaique, des Semiconducteurs et des Nanostructures, Centre de Recherche et des Technologies de l' energie, BP 95 Hammam-Lif 2050 (Tunisia); Eljani, B. [Unite de recherche sur les Hetero-Epitaxie et Applications, Faculte des Sciences de Monastir (Tunisia); Ouerghi, A. [Laboratoire de Photonique et de Nanostructures, CNRS Route de Nozay 91 46a0, Marcoussis (France); Chtourou, R. [Laboratoire de Photovoltaique, des Semiconducteurs et des Nanostructures, Centre de Recherche et des Technologies de l' energie, BP 95 Hammam-Lif 2050 (Tunisia)

    2011-05-15

    Photoreflectance and photoluminescence studies were performed to characterize InAs ultrathin layer embedded in Si-delta-doped GaAs/AlGaAs high electron mobility transistors. These structures were grown by Molecular Beam Epitaxy on (1 0 0) oriented GaAs substrates with different silicon-delta-doped layer densities. Interband energy transitions in the InAs ultrathin layer quantum well were observed below the GaAs band gap in the photoreflectance spectra, and assigned to electron-heavy-hole (E{sub e-hh}) and electron-light-hole (E{sub e-lh}) fundamental transitions. These transitions were shifted to lower energy with increasing silicon-{delta}-doping density. This effect is in good agreement with our theoretical results based on a self-consistent solution of the coupled Schroedinger and Poisson equations and was explained by increased escape of photogenerated carriers and enhanced Quantum Confined Stark Effect in the Si-delta-doped InAs/GaAs QW. In the photoreflectance spectra, not only the channel well interband energy transitions were observed, but also features associated with the GaAs and AlGaAs bulk layers located at about 1.427 and 1.8 eV, respectively. By analyzing the Franz-Keldysh Oscillations observed in the spectral characteristics of Si-{delta}-doped samples, we have determined the internal electric field introduced by ionized Si-{delta}-doped centers. We have observed an increase in the electric field in the InAs ultrathin layer with increasing silicon content. The results are explained in terms of doping dependent ionized impurities densities and surface charges. - Research highlights: {yields} Studying HEMTs structures with different silicon doping content. {yields} An increase of the electric field in the InAs layer with increasing Si content. {yields} The interband energy transitions in the HEMTs structures have been obtained from PR. {yields} Experimental and theoretical values of transitions energies were in good agreement.

  19. People of the Delta

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, L.

    2007-09-15

    The potential impacts of both global warming and the $16 billion Mackenzie pipeline project on communities in the Mackenzie Delta were discussed. A consortium of oil and gas developers is now planning to exploit the natural gas reserves located near the mouth of the Delta, whose largest town is Inuvik. The project is expected to place a significant burden on the resources and infrastructure of the town, which currently has a population of 6000. The community, comprised of a diverse international population and an Inuit majority, is largely in favour of the pipeline project. The Inuvialuit people have invested a significant amount of time to ensure that the project, which was stalled due to land claims in 1977, benefits their communities. Public hearings are now being held to consider the potential environmental and socio-economic impacts of the project. Separate hearings are also being held to consider the project's design. The pipeline project includes 3 natural gas production facilities, a gas-processing facility, a pipeline gathering system, a 480 km natural gas liquids pipeline to the Northwest Territories, and a 1220 km natural gas pipeline to northern Alberta. The pipeline will be buried to minimize environmental impacts. The project is expected to create 8200 jobs at the height of its construction. However, communities located near the site of the natural gas reserves, such as the town of Tuktoyaktuk are now threatened by soil erosion that has been attributed to global warming. 21 figs.

  20. A Study on Developing Evaluation Criteria for Electronic Resources in Evaluation Indicators of Libraries

    Science.gov (United States)

    Noh, Younghee

    2010-01-01

    This study aimed to improve the current state of electronic resource evaluation in libraries. While the use of Web DB, e-book, e-journal, and other e-resources such as CD-ROM, DVD, and micro materials is increasing in libraries, their use is not comprehensively factored into the general evaluation of libraries and may diminish the reliability of…

  1. Modeling Anthropogenic Impact on Sediment Balance and Relative Sea-Level Rise in Contemporary and Future Deltas

    Science.gov (United States)

    Tessler, Z. D.; Vorosmarty, C. J.; Overeem, I.; Syvitski, J. P.

    2017-12-01

    Modern deltas are dependent on human-mediated freshwater and sediment fluxes. Changes to these fluxes impact delta biogeophysical functioning, and affect the long-term sustainability of these landscapes for both human and natural systems. Here we present contemporary estimates of long-term mean sediment balance and relative sea-level rise across 46 global deltas. We model ongoing development and scenarios of future water resource management and hydropower infrastructure in upstream river basins to explore how changing sediment fluxes impact relative sea-level in coastal delta systems. Model results show that contemporary sediment fluxes, anthropogenic drivers of land subsidence, and sea-level rise result in relative sea-level rise rates in deltas that average 6.8 mm/year. Currently planned or under-construction dams can be expected to increase rates of relative sea-level rise on the order of 1 mm/year. Some deltas systems, including the Magdalena, Orinoco, and Indus, are highly sensitive to future impoundment of river basins, with RSLR rates increasing up to 4 mm/year in a high-hydropower-utilization scenario. Sediment fluxes may be reduced by up to 60% in the Danube and 21% in the Ganges-Brahmaputra-Megnha if all currently planned dams are constructed. Reduced sediment retention on deltas due to increased river channelization and local flood controls increases RSLR on average by nearly 2 mm/year. Long-term delta sustainability requires a more complete understanding of how geophysical and anthropogenic change impact delta geomorphology. Strategies for sustainable delta management that focus on local and regional drivers of change, especially groundwater and hydrocarbon extraction and upstream dam construction, can be highly impactful even in the context of global climate-induced sea-level rise.

  2. Large old trees influence patterns of delta13C and delta15N in forests.

    Science.gov (United States)

    Weber, Pascale; Bol, Roland; Dixon, Liz; Bardgett, Richard D

    2008-06-01

    Large old trees are the dominant primary producers of native pine forest, but their influence on spatial patterns of soil properties and potential feedback to tree regeneration in their neighbourhood is poorly understood. We measured stable isotopes of carbon (delta(13)C) and nitrogen (delta(15)N) in soil and litter taken from three zones of influence (inner, middle and outer zone) around the trunk of freestanding old Scots pine (Pinus sylvestris L.) trees, to determine the trees' influence on below-ground properties. We also measured delta(15)N and delta(13)C in wood cores extracted from the old trees and from regenerating trees growing within their three zones of influence. We found a significant and positive gradient in soil delta(15)N from the inner zone, nearest to the tree centre, to the outer zone beyond the tree crown. This was probably caused by the higher input of (15)N-depleted litter below the tree crown. In contrast, the soil delta(13)C did not change along the gradient of tree influence. Distance-related trends, although weak, were visible in the wood delta(15)N and delta(13)C of regenerating trees. Moreover, the wood delta(15)N of small trees showed a weak negative relationship with soil N content in the relevant zone of influence. Our results indicate that large old trees control below-ground conditions in their immediate surroundings, and that stable isotopes might act as markers for the spatial and temporal extent of these below-ground effects. John Wiley & Sons, Ltd

  3. An analytical framework for strategic delta planning : negotiating consent for long-term sustainable delta development

    NARCIS (Netherlands)

    Seijger, C.; Douven, W; Hermans, L.M.; Evers, J.; Phi, H. L.; Brunner, J.; Pols, L.; Ligtvoet, W.; Koole, S.; Slager, K.; Vermoolen, M.S.; Hasan, S.; Hoang, V. T M; van Halsema, G

    2016-01-01

    Sectoral planning on water, agriculture and urban development has not been able to prevent increased flood risks and environmental degradation in many deltas. Governments conceive strategic delta planning as a promising planning approach and develop strategic delta plans. Such plans are linked to

  4. Catalyzing action towards the sustainability of deltas: deltas as integrated socio-ecological systems and sentinels of regional and global change

    Science.gov (United States)

    Foufoula-Georgiou, E.; Tessler, Z. D.; Brondizio, E.; Overeem, I.; Renaud, F.; Sebesvari, Z.; Nicholls, R. J.; Anthony, E.

    2016-12-01

    Deltas are highly dynamic and productive environments: they are food baskets of the world, home to biodiverse and rich ecosystems, and they play a central role in food and water security. However, they are becoming increasingly vulnerable to risks arising from human activities, land subsidence, regional water management, global sea-level rise, and climate extremes. Our Belmont Forum DELTAS project (BF-DELTAS: Catalyzing actions towards delta sustainability) encompasses an international network of interdisciplinary research collaborators with focal areas in the Mekong, Ganges Brahmaputra, and the Amazon deltas. The project is organized around five main modules: (1) developing an analytical framework for assessing delta vulnerability and scenarios of change (Delta-SRES), (2) developing an open-acess, science-based integrative modeling framework for risk assessment and decision support (Delta-RADS), (3) developing tools to support quantitative mapping of the bio-physical and socio-economic environments of deltas and consolidate bio-physical and social data within shared data repositories (Delta-DAT), (4) developing Global Delta Vulnerability Indices (Delta-GDVI) that capture current and projected scenarios for major deltas around the world , and (5) collaborating with regional stakeholders to put the science, modeling, and data into action (Delta-ACT). In this talk, a research summary will be presented on three research domains around which significant collaborative work was developed: advancing biophysical classification of deltas, understanding deltas as coupled socio-ecological systems, and analyzing and informing social and environmental vulnerabilities in delta regions.

  5. DELTA-DIESEL ENGINE LIGHT TRUCK APPLICATION Contract DE-FC05-97OR22606 Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Hakim, Nabil Balnaves, Mike

    2003-05-27

    DELTA Diesel Engine Light Truck Application End of Contract Report DE-FC05-97-OR22606 EXECUTIVE SUMMARY This report is the final technical report of the Diesel Engine Light Truck Application (DELTA) program under contract DE-FC05-97-OR22606. During the course of this contract, Detroit Diesel Corporation analyzed, designed, tooled, developed and applied the ''Proof of Concept'' (Generation 0) 4.0L V-6 DELTA engine and designed the successor ''Production Technology Demonstration'' (Generation 1) 4.0L V-6 DELTA engine. The objectives of DELTA Program contract DE-FC05-97-OR22606 were to: Demonstrate production-viable diesel engine technologies, specifically intended for the North American LDT and SUV markets; Demonstrate emissions compliance with significant fuel economy advantages. With a clean sheet design, DDC produced the DELTA engine concept promising the following attributes: 30-50% improved fuel economy; Low cost; Good durability and reliability; Acceptable noise, vibration and harshness (NVH); State-of-the-art features; Even firing, 4 valves per cylinder; High pressure common rail fuel system; Electronically controlled; Turbocharged, intercooled, cooled EGR; Extremely low emissions via CLEAN Combustion{copyright} technology. To demonstrate the engine technology in the SUV market, DDC repowered a 1999 Dodge Durango with the DELTA Generation 0 engine. Fuel economy improvements were approximately 50% better than the gasoline engine replaced in the vehicle.

  6. THE MODEL OF LINGUISTIC TEACHERS’ COMPETENCY DEVELOPMENT ON DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES IN THE MOODLE SYSTEM

    OpenAIRE

    Anton M. Avramchuk

    2017-01-01

    The article is devoted to the problem of developing the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system. The concept of "the competence of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system" is justified and defined. Identified and characterized the components by which the levels of the competency development of teachers of language disciplines on designing ...

  7. Delta Morphodynamics Matters! Ecosystem Services, Poverty and Morphodynamic Change in the Ganges-Brahmaputra Mega-Delta

    Science.gov (United States)

    Nicholls, R. J.; Adger, N.; Allan, A.; Darby, S. E.; Hutton, C.; Matthews, Z.; Rahman, M.; Whitehead, P. G.; Wolf, J.

    2013-12-01

    The world's deltas are probably the most vulnerable type of coastal environment, and they face multiple stresses in the coming decades. These stresses include, amongst others, local drivers due to land subsidence, population growth and urbanisation within the deltas, regional drivers due to changes in catchment management (e.g. upstream land use and dam construction), as well as global climate change impacts such as sea-level rise. At the same time, the ecosystem services of river deltas support high population densities, with around 14% of the global population inhabiting deltas. A large proportion of these people experience extremes of poverty and they are therefore severely exposed to vulnerability from environmental and ecological stress and degradation. In areas close to or below the poverty boundary, both subsistence and cash elements of the economy tend to rely disproportionately heavily on ecosystem services which underpin livelihoods. Therefore, to sustainably manage delta environments they must be viewed as complex social-environmental systems where change is only partially driven by physical drivers such as sea level rise and climate change, and human-induced development activities are also critical. Here we outline a new conceptual framework for the development of methods to understand and characterise the key drivers of change in ecosystem services that affect the environment and economic status of populous deltas, focusing specifically on the Ganges-Brahmaputra-Meghna (GBM) mega-delta. The GBM delta is characterised by densely populated coastal lowlands with significant poverty, with livelihoods supported to a large extent by natural ecosystems such as the Sunderbahns (the largest mangrove forest in the world). However, the GBM delta is under severe development pressure due to many growing cities. At present the importance of ecosystems services to poverty and livelihoods is poorly understood. This is due to due to the complexity of interactions

  8. Determining the level of awareness of the physicians in using the variety of electronic information resources and the effecting factors.

    Science.gov (United States)

    Papi, Ahmad; Ghazavi, Roghayeh; Moradi, Salimeh

    2015-01-01

    Understanding of the medical society's from the types of information resources for quick and easy access to information is an imperative task in medical researches and management of the treatment. The present study was aimed to determine the level of awareness of the physicians in using various electronic information resources and the factors affecting it. This study was a descriptive survey. The data collection tool was a researcher-made questionnaire. The study population included all the physicians and specialty physicians of the teaching hospitals affiliated to Isfahan University of Medical Sciences and numbered 350. The sample size based on Morgan's formula was set at 180. The content validity of the tool was confirmed by the library and information professionals and the reliability was 95%. Descriptive statistics were used including the SPSS software version 19. On reviewing the need of the physicians to obtain the information on several occasions, the need for information in conducting the researches was reported by the maximum number of physicians (91.9%) and the usage of information resources, especially the electronic resources, formed 65.4% as the highest rate with regard to meeting the information needs of the physicians. Among the electronic information databases, the maximum awareness was related to Medline with 86.5%. Among the various electronic information resources, the highest awareness (43.3%) was related to the E-journals. The highest usage (36%) was also from the same source. The studied physicians considered the most effective deterrent in the use of electronic information resources as being too busy and lack of time. Despite the importance of electronic information resources for the physician's community, there was no comprehensive knowledge of these resources. This can lead to less usage of these resources. Therefore, careful planning is necessary in the hospital libraries in order to introduce the facilities and full capabilities of the

  9. Managing Selection for Electronic Resources: Kent State University Develops a New System to Automate Selection

    Science.gov (United States)

    Downey, Kay

    2012-01-01

    Kent State University has developed a centralized system that manages the communication and work related to the review and selection of commercially available electronic resources. It is an automated system that tracks the review process, provides selectors with price and trial information, and compiles reviewers' feedback about the resource. It…

  10. Future Change to Tide-Influenced Deltas

    Science.gov (United States)

    Nienhuis, Jaap H.; Hoitink, A. J. F. (Ton); Törnqvist, Torbjörn E.

    2018-04-01

    Tides tend to widen deltaic channels and shape delta morphology. Here we present a predictive approach to assess a priori the effect of fluvial discharge and tides on deltaic channels. We show that downstream channel widening can be quantified by the ratio of the tide-driven discharge and the fluvial discharge, along with a second metric representing flow velocities. A test of our new theory on a selection of 72 deltas globally shows good correspondence to a wide range of environments, including wave-dominated deltas, river-dominated deltas, and alluvial estuaries. By quantitatively relating tides and fluvial discharge to delta morphology, we offer a first-order prediction of deltaic change that may be expected from altered delta hydrology. For example, we expect that reduced fluvial discharge in response to dam construction will lead to increased tidal intrusion followed by enhanced tide-driven sediment import into deltas, with implications for navigation and other human needs.

  11. From Natural to Design River Deltas

    Science.gov (United States)

    Giosan, Liviu

    2016-04-01

    Productive and biologically diverse, deltaic lowlands attracted humans since prehistory and may have spurred the emergence of the first urban civilizations. Deltas continued to be an important nexus for economic development across the world and are currently home for over half a billion people. But recently, under the double whammy of sea level rise and inland sediment capture behind dams, they have become the most threatened coastal landscape. Here I will address several deceptively simple questions to sketch some unexpected answers using example deltas from across the world from the Arctic to the Tropics, from the Danube to the Indus, Mississippi to Godavari and Krishna, Mackenzie to Yukon. What is a river delta? What is natural and what is not in a river delta? Are the geological and human histories of a delta important for its current management? Is maintaining a delta the same to building a new one? Can we design better deltas than Nature? These answers help us see clearly that survival of deltas in the next century depends on human intervention and is neither assured nor simple to address or universally applicable. Empirical observations on the hydrology, geology, biology and biochemistry of deltas are significantly lagging behind modeling capabilities endangering the applicability of numerical-based reconstruction solutions and need to be ramped up significantly and rapidly across the world.

  12. End-of-life resource recovery from emerging electronic products

    DEFF Research Database (Denmark)

    Parajuly, Keshav; Habib, Komal; Cimpan, Ciprian

    2016-01-01

    Integrating product design with appropriate end-of-life (EoL) processing is widely recognized to have huge potentials in improving resource recovery from electronic products. In this study, we investigate both the product characteristics and EoL processing of robotic vacuum cleaner (RVC), as a case...... of emerging electronic product, in order to understand the recovery fate of different materials and its linkage to product design. Ten different brands of RVC were dismantled and their material composition and design profiles were studied. Another 125 RVCs (349 kg) were used for an experimental trial...... at a conventional ‘shred-and-separate’ type preprocessing plant in Denmark. A detailed material flow analysis was performed throughout the recycling chain. The results show a mismatch between product design and EoL processing, and the lack of practical implementation of ‘Design for EoL’ thinking. In the best...

  13. Delta isobars in neutron stars

    Directory of Open Access Journals (Sweden)

    Pagliara Giuseppe

    2015-01-01

    Full Text Available The appearance of delta isobars in beta-stable matter is regulated by the behavior of the symmetry energy at densities larger than saturation density. We show that by taking into account recent constraints on the density derivative of the symmetry energy and the theoretical and experimental results on the excitations of delta isobars in nuclei, delta isobars are necessary ingredients for the equations of state used for studying neutron stars. We analyze the effect of the appearance of deltas on the structure of neutron stars: as in the case of hyperons, matter containing delta is too soft for allowing the existence of 2M⊙ neutron stars. Quark stars on the other hand, could reach very massive configurations and they could form from a process of conversion of hadronic stars in which an initial seed of strangeness appears through hyperons.

  14. Use of electronic sales data to tailor nutrition education resources for an ethnically diverse population.

    Science.gov (United States)

    Eyles, H; Rodgers, A; Ni Mhurchu, C

    2010-02-01

    Nutrition education may be most effective when personally tailored. Individualised electronic supermarket sales data offer opportunities to tailor nutrition education using shopper's usual food purchases. The present study aimed to use individualised electronic supermarket sales data to tailor nutrition resources for an ethnically diverse population in a large supermarket intervention trial in New Zealand. Culturally appropriate nutrition education resources (i.e. messages and shopping lists) were developed with the target population (through two sets of focus groups) and ethnic researchers. A nutrient database of supermarket products was developed using retrospective sales data and linked to participant sales to allow tailoring by usual food purchases. Modified Heart Foundation Tick criteria were used to identify 'healthier' products in the database suitable for promotion in the resources. Rules were developed to create a monthly report listing the tailored and culturally targeted messages to be sent to each participant, and to produce automated, tailored shopping lists. Culturally targeted nutrition messages (n = 864) and shopping lists (n = 3 formats) were developed. The food and nutrient database (n = 3000 top-selling products) was created using 12 months of retrospective sales data, and comprised 60%'healthier' products. Three months of baseline sales data were used to determine usual food purchases. Tailored resources were successfully mailed to 123 Māori, 52 Pacific and 346 non-Māori non-Pacific participants over the 6-month trial intervention period. Electronic supermarket sales data can be used to tailor nutrition education resources for a large number of ethnically diverse supermarket shoppers.

  15. Formation Conditions and Sedimentary Characteristics of a Triassic Shallow Water Braided Delta in the Yanchang Formation, Southwest Ordos Basin, China.

    Directory of Open Access Journals (Sweden)

    Ziliang Liu

    Full Text Available A large, shallow braided river delta sedimentary system developed in the Yanchang Formation during the Triassic in the southwest of the Ordos basin. In this braided delta system, abundant oil and gas resources have been observed, and the area is a hotspot for oil and gas resource exploration. Through extensive field work on outcrops and cores and analyses of geophysical data, it was determined that developments in the Late Triassic produced favorable geological conditions for the development of shallow water braided river deltas. Such conditions included a large basin, flat terrain, and wide and shallow water areas; wet and dry cyclical climate changes; ancient water turbulence; dramatic depth cycle changes; ancient uplift development; strong weathering of parent rock; and abundant supply. The shallow water braided river delta showed grain sediment granularity, plastic debris, and sediment with mature composition and structure that reflected the strong hydrodynamic environment of large tabular cross-bedding, wedge cross-bedding, and multiple positive rhythms superimposed to form a thick sand body layer. The branch river bifurcation developed underwater, and the thickness of the sand body increased further, indicating that the slope was slow and located in shallow water. The seismic responses of the braided river delta reflected strong shallow water performance, indicated by a progradation seismic reflection phase axis that was relatively flat; in addition, the seismic reflection amplitude was strong and continuous with a low angle and extended over considerable distances (up to 50 km. The sedimentary center was close to the provenance, the width of the river was large, and a shallow sedimentary structure and a sedimentary rhythm were developed. The development of the delta was primarily controlled by tectonic activity and changes in the lake level; as a result, the river delta sedimentary system eventually presented a "small plain, big front

  16. Formation Conditions and Sedimentary Characteristics of a Triassic Shallow Water Braided Delta in the Yanchang Formation, Southwest Ordos Basin, China.

    Science.gov (United States)

    Liu, Ziliang; Shen, Fang; Zhu, Xiaomin; Li, Fengjie; Tan, Mengqi

    2015-01-01

    A large, shallow braided river delta sedimentary system developed in the Yanchang Formation during the Triassic in the southwest of the Ordos basin. In this braided delta system, abundant oil and gas resources have been observed, and the area is a hotspot for oil and gas resource exploration. Through extensive field work on outcrops and cores and analyses of geophysical data, it was determined that developments in the Late Triassic produced favorable geological conditions for the development of shallow water braided river deltas. Such conditions included a large basin, flat terrain, and wide and shallow water areas; wet and dry cyclical climate changes; ancient water turbulence; dramatic depth cycle changes; ancient uplift development; strong weathering of parent rock; and abundant supply. The shallow water braided river delta showed grain sediment granularity, plastic debris, and sediment with mature composition and structure that reflected the strong hydrodynamic environment of large tabular cross-bedding, wedge cross-bedding, and multiple positive rhythms superimposed to form a thick sand body layer. The branch river bifurcation developed underwater, and the thickness of the sand body increased further, indicating that the slope was slow and located in shallow water. The seismic responses of the braided river delta reflected strong shallow water performance, indicated by a progradation seismic reflection phase axis that was relatively flat; in addition, the seismic reflection amplitude was strong and continuous with a low angle and extended over considerable distances (up to 50 km). The sedimentary center was close to the provenance, the width of the river was large, and a shallow sedimentary structure and a sedimentary rhythm were developed. The development of the delta was primarily controlled by tectonic activity and changes in the lake level; as a result, the river delta sedimentary system eventually presented a "small plain, big front" character.

  17. Availability, Level of Use and Constraints to Use of Electronic Resources by Law Lecturers in Public Universities in Nigeria

    Science.gov (United States)

    Amusa, Oyintola Isiaka; Atinmo, Morayo

    2016-01-01

    (Purpose) This study surveyed the level of availability, use and constraints to use of electronic resources among law lecturers in Nigeria. (Methodology) Five hundred and fifty-two law lecturers were surveyed and four hundred and forty-two responded. (Results) Data analysis revealed that the level of availability of electronic resources for the…

  18. Improved γ-linolenic acid production in Mucor circinelloides by homologous overexpressing of delta-12 and delta-6 desaturases.

    Science.gov (United States)

    Zhang, Yao; Luan, Xiao; Zhang, Huaiyuan; Garre, Victoriano; Song, Yuanda; Ratledge, Colin

    2017-06-21

    γ-Linolenic acid (GLA) is important because of its nutritional value and medicinal applications. Although the biosynthetic pathways of some plant and microbial GLA have been deciphered, current understanding of the correlation between desaturases and GLA synthesis in oleaginous fungi is incomplete. In previous work, we found that a large amount of oleic acid (OA) had not been converted to linoleic acid (LA) or GLA in Mucor circinelloides CBS 277.49, which may be due to inadequate activities of the delta-12 or delta-6 desaturases, and thus leading to the accumulation of OA and LA. Thus, it is necessary to explore the main contributing factor during the process of GLA biosynthesis in M. circinelloides. To enhance GLA production in M. circinelloides, homologous overexpression of delta-12 and two delta-6 desaturases (named delta-6-1 and delta-6-2, respectively) were analyzed. When delta-6 desaturase were overexpressed in M. circinelloides, up to 43% GLA was produced in the total fatty acids, and the yield of GLA reached 180 mg/l, which were, respectively, 38 and 33% higher than the control strain. These findings revealed that delta-6 desaturase (especially for delta-6-1 desaturase) plays an important role in GLA synthesis by M. circinelloides. The strain overexpressing delta-6-1 desaturase may have potential application in microbial GLA production.

  19. Financial Performance of Hospitals in the Mississippi Delta Region Under the Hospital Readmissions Reduction Program and Hospital Value-based Purchasing Program.

    Science.gov (United States)

    Chen, Hsueh-Fen; Karim, Saleema; Wan, Fei; Nevola, Adrienne; Morris, Michael E; Bird, T Mac; Tilford, J Mick

    2017-11-01

    Previous studies showed that the Hospital Readmissions Reduction Program (HRRP) and the Hospital Value-based Purchasing Program (HVBP) disproportionately penalized hospitals caring for the poor. The Mississippi Delta Region (Delta Region) is among the most socioeconomically disadvantaged areas in the United States. The financial performance of hospitals in the Delta Region under both HRRP and HVBP remains unclear. To compare the differences in financial performance under both HRRP and HVBP between hospitals in the Delta Region (Delta hospitals) and others in the nation (non-Delta hospitals). We used a 7-year panel dataset and applied difference-in-difference models to examine operating and total margin between Delta and non-Delta hospitals in 3 time periods: preperiod (2008-2010); postperiod 1 (2011-2012); and postperiod 2 (2013-2014). The Delta hospitals had a 0.89% and 4.24% reduction in operating margin in postperiods 1 and 2, respectively, whereas the non-Delta hospitals had 1.13% and 1% increases in operating margin in postperiods 1 and 2, respectively. The disparity in total margins also widened as Delta hospitals had a 1.98% increase in postperiod 1, but a 0.30% reduction in postperiod 2, whereas non-Delta hospitals had 1.27% and 2.28% increases in postperiods 1 and 2, respectively. The gap in financial performance between Delta and non-Delta hospitals widened following the implementation of HRRP and HVBP. Policy makers should modify these 2 programs to ensure that resources are not moved from the communities that need them most.

  20. Entropy and optimality in river deltas

    Science.gov (United States)

    Tejedor, Alejandro; Longjas, Anthony; Edmonds, Douglas A.; Zaliapin, Ilya; Georgiou, Tryphon T.; Rinaldo, Andrea; Foufoula-Georgiou, Efi

    2017-10-01

    The form and function of river deltas is intricately linked to the evolving structure of their channel networks, which controls how effectively deltas are nourished with sediments and nutrients. Understanding the coevolution of deltaic channels and their flux organization is crucial for guiding maintenance strategies of these highly stressed systems from a range of anthropogenic activities. To date, however, a unified theory explaining how deltas self-organize to distribute water and sediment up to the shoreline remains elusive. Here, we provide evidence for an optimality principle underlying the self-organized partition of fluxes in delta channel networks. By introducing a suitable nonlocal entropy rate (nER) and by analyzing field and simulated deltas, we suggest that delta networks achieve configurations that maximize the diversity of water and sediment flux delivery to the shoreline. We thus suggest that prograding deltas attain dynamically accessible optima of flux distributions on their channel network topologies, thus effectively decoupling evolutionary time scales of geomorphology and hydrology. When interpreted in terms of delta resilience, high nER configurations reflect an increased ability to withstand perturbations. However, the distributive mechanism responsible for both diversifying flux delivery to the shoreline and dampening possible perturbations might lead to catastrophic events when those perturbations exceed certain intensity thresholds.

  1. First observation of electrons in the ATLAS detector

    CERN Document Server

    Kraus, J; The ATLAS collaboration

    2010-01-01

    The special topology of cosmic events traversing all subdetectors offers the unique opportunity to investigate the combined performance of ATLAS in identifying and reconstructing particles before first collisions. High-energy delta electrons in cosmic data are studied which are produced by cosmic muons through ionisation of the inner detector material. A method of separating knock-on electrons from the large background of muon bremsstrahlung is presented accounting for the special nature of cosmic events and utilizing the ATLAS tools to identify electrons with their characteristic properties. The resulting isolation of a sample of 32 delta electrons out of 3.5 million cosmic ray events with a high-level trigger track candidate in the inner detector barrel has for the first time enabled an observation and investigation of real electrons in ATLAS.

  2. A systematic review of portable electronic technology for health education in resource-limited settings.

    Science.gov (United States)

    McHenry, Megan S; Fischer, Lydia J; Chun, Yeona; Vreeman, Rachel C

    2017-08-01

    The objective of this study is to conduct a systematic review of the literature of how portable electronic technologies with offline functionality are perceived and used to provide health education in resource-limited settings. Three reviewers evaluated articles and performed a bibliography search to identify studies describing health education delivered by portable electronic device with offline functionality in low- or middle-income countries. Data extracted included: study population; study design and type of analysis; type of technology used; method of use; setting of technology use; impact on caregivers, patients, or overall health outcomes; and reported limitations. Searches yielded 5514 unique titles. Out of 75 critically reviewed full-text articles, 10 met inclusion criteria. Study locations included Botswana, Peru, Kenya, Thailand, Nigeria, India, Ghana, and Tanzania. Topics addressed included: development of healthcare worker training modules, clinical decision support tools, patient education tools, perceptions and usability of portable electronic technology, and comparisons of technologies and/or mobile applications. Studies primarily looked at the assessment of developed educational modules on trainee health knowledge, perceptions and usability of technology, and comparisons of technologies. Overall, studies reported positive results for portable electronic device-based health education, frequently reporting increased provider/patient knowledge, improved patient outcomes in both quality of care and management, increased provider comfort level with technology, and an environment characterized by increased levels of technology-based, informal learning situations. Negative assessments included high investment costs, lack of technical support, and fear of device theft. While the research is limited, portable electronic educational resources present promising avenues to increase access to effective health education in resource-limited settings, contingent

  3. Above room-temperature ferromagnetism of Mn delta-doped GaN nanorods

    International Nuclear Information System (INIS)

    Lin, Y. T.; Wadekar, P. V.; Kao, H. S.; Chen, T. H.; Chen, Q. Y.; Tu, L. W.; Huang, H. C.; Ho, N. J.

    2014-01-01

    One-dimensional nitride based diluted magnetic semiconductors were grown by plasma-assisted molecular beam epitaxy. Delta-doping technique was adopted to dope GaN nanorods with Mn. The structural and magnetic properties were investigated. The GaMnN nanorods with a single crystalline structure and with Ga sites substituted by Mn atoms were verified by high-resolution x-ray diffraction and Raman scattering, respectively. Secondary phases were not observed by high-resolution x-ray diffraction and high-resolution transmission electron microscopy. In addition, the magnetic hysteresis curves show that the Mn delta-doped GaN nanorods are ferromagnetic above room temperature. The magnetization with magnetic field perpendicular to GaN c-axis saturates easier than the one with field parallel to GaN c-axis

  4. The evolution of a subaqueous delta in the Anthropocene: A stratigraphic investigation of the Brazos River delta, TX USA

    Science.gov (United States)

    Carlin, Joseph A.; Dellapenna, Timothy M.

    2015-12-01

    Globally, deltas are increasingly threatened by anthropogenic activities. As a result, deltas now evolve through the combined effects of natural and human-induced processes occurring throughout the fluvial-deltaic system. The Brazos River delta, located along the Texas coast in the northwestern Gulf of Mexico, and its watershed have been impacted by direct and indirect human activities since the late 19th century. This provides an opportunity to investigate how such alterations have shaped the evolution of a delta in the Anthropocene, a time when humans are drivers of geological change. Historic alteration to the delta and watershed include extensive agricultural activity, jetty construction at the mouth in the late 1890s, mouth diversion ~10 km to the southwest in 1929, and reservoir construction throughout the early and mid 20th Century. Three subaerial deltaic geometries provided the framework to connect subaerial deltaic responses, to the anthropogenic alterations, to the resulting stratigraphic characteristics observed in the subaqueous delta. This study utilized high-resolution geophysical data (swath bathymetry, side scan sonar, CHIRP subbottom profiling) on the subaqueous delta to investigate the subaqueous delta stratigraphy and infer the processes that shaped the deltaic record over time. The results showed distinct areas across the subaqueous delta that were dominated by erosion and deposition. Erosional areas corresponded to earlier growth phase depocenters being exposed at the surface, while the depositional areas corresponded to areas with the most recent growth phase depocenter overlying the earlier depocenters. These results highlight that the subaqueous depocenter has migrated westward over time, consistent with the observed changes to the subaerial delta. Additionally, the data showed that evidence for these past growth phases and depocenters may be preserved within the subaqueous delta, even after subaerial portions of the delta returned to pre

  5. The relativistic electron wave equation

    International Nuclear Information System (INIS)

    Dirac, P.A.M.

    1977-08-01

    The paper was presented at the European Conference on Particle Physics held in Budapest between the 4th and 9th July of 1977. A short review is given on the birth of the relativistic electron wave equation. After Schroedinger has shown the equivalence of his wave mechanics and the matrix mechanics of Heisenberg, a general transformation theory was developed by the author. This theory required a relativistic wave equation linear in delta/delta t. As the Klein--Gordon equation available at this time did not satisfy this condition the development of a new equation became necessary. The equation which was found gave the value of the electron spin and magnetic moment automatically. (D.P.)

  6. deltaPlotR: An R Package for Di?erential Item Functioning Analysis with Ango? s Delta Plot

    OpenAIRE

    David Magis; Bruno Facon

    2014-01-01

    Angoff's delta plot is a straightforward and not computationally intensive method to identify differential item functioning (DIF) among dichotomously scored items. This approach was recently improved by proposing an optimal threshold selection and by considering several item purification processes. Moreover, to support practical DIF analyses with the delta plot and these improvements, the R package deltaPlotR was also developed. The purpose of this paper is twofold: to outline the delta plot ...

  7. SAGES: a suite of freely-available software tools for electronic disease surveillance in resource-limited settings.

    Directory of Open Access Journals (Sweden)

    Sheri L Lewis

    Full Text Available Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations.

  8. Use and Cost of Electronic Resources in Central Library of Ferdowsi University Based on E-metrics

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Davarpanah

    2012-07-01

    Full Text Available The purpose of this study was to investigate the usage of electronic journals in Ferdowsi University, Iran based on e-metrics. The paper also aimed to emphasize the analysis of cost-benefit and the correlation between the journal impact factors and the usage data. In this study experiences of Ferdowsi University library on licensing and usage of electronic resources was evaluated by providing a cost-benefit analysis based on the cost and usage statistics of electronic resources. Vendor-provided data were also compared with local usage data. The usage data were collected by tracking web-based access locally, and by collecting vender-provided usage data. The data sources were one-year of vendor-supplied e-resource usage data such as Ebsco, Elsevier, Proquest, Emerald, Oxford and Springer and local usage data collected from the Ferdowsi university web server. The study found that actual usage values differ for vendor-provided data and local usage data. Elsevier has got the highest usage degree in searches, sessions and downloads. Statistics also showed that a small number of journals satisfy significant amount of use while the majority of journals were used less frequent and some were never used at all. The users preferred the PDF rather than HTML format. The data in subject profile suggested that the provided e-resources were best suited to certain subjects. There was no correlation between IF and electronic journal use. Monitoring the usage of e-resources gained increasing importance for acquisition policy and budget decisions. The article provided information about local metrics for the six surveyed vendors/publishers, e.g. usage trends, requests per package, cost per use as related to the scientific specialty of the university.

  9. Coordination and health sector adaptation to climate change in the Vietnamese Mekong Delta

    Directory of Open Access Journals (Sweden)

    Daniel Gilfillan

    2017-09-01

    Full Text Available This research examines the impact of three coordination dimensions on health sector adaptation to climate change in the Vietnamese Mekong Delta: cross-scale, cross-sectoral, and cross-boundary. While tasks are divided up between government ministries and departments in Vietnam, there is little collaboration on issues that span mandates. Similarly, while water flows in the Vietnamese Mekong Delta take resource management and health concerns across provincial boundaries, formal mechanisms for interprovincial collaboration are lacking. While decentralization efforts have sought to devolve authority and decision making to lower levels, there is continued state-centered top-down policy making, and this limits collaborative coordination across scales. All three of these issues inhibit health sector adaptation to climate change in the Vietnamese Mekong Delta, and though these coordination issues are recognized by the Vietnamese government, to date there has been little success in addressing them. The authors hope to stimulate further debate and discussion of coordination problems, and conclude that despite some significant challenges, the South West Steering Committee could play a facilitating role coordinating climate change responses in health and other sectors across the Vietnamese Mekong Delta. As an analysis of governance, this research is applicable to other areas and sectors in Vietnam, as well as to other parts of South East Asia.

  10. Variation in Spring Nearshore Resident Fish Species Composition and Life Histories in the Lower San Joaquin Watershed and Delta

    Directory of Open Access Journals (Sweden)

    Larry R. Brown

    2006-09-01

    Full Text Available Providing freshwater to human populations while protecting or rehabilitating ecosystem health is a significant challenge to water resource managers and requires accurate knowledge of aquatic resources. Previous studies of fish assemblages in the San Francisco Estuary and watershed have focused on specific habitat types, water bodies, or geographic subregions. In this study, we use seining data from two monitoring programs to provide an integrated view of spring nearshore resident fish species composition and life history characteristics in five regions: the San Joaquin River, the upper Sacramento River, the lower Sacramento River, the northern Sacramento-San Joaquin Delta (North Delta, and the Interior Delta. Data for the period March-May from 1994 to 2002, showed that spring species composition of the San Joaquin River was very different from the other four regions. Total catch in the San Joaquin River was dominated by small, short-lived batch spawning alien species (93%, particularly red shiner Cyprinella lutrensis (>75% of total catch. The upper and lower Sacramento River were very similar in species composition and life history characteristics and less dominated by alien fish (

  11. Delta hedging strategies comparison

    DEFF Research Database (Denmark)

    De Giovanni, Domenico; Ortobelli, S.; Rachev, S.T.

    2008-01-01

    In this paper we implement dynamic delta hedging strategies based on several option pricing models. We analyze different subordinated option pricing models and we examine delta hedging costs using ex-post daily prices of S&P 500. Furthermore, we compare the performance of each subordinated model...

  12. Delta-electron emission in fast heavy ion atom collisions

    International Nuclear Information System (INIS)

    Schmidt-Boecking, H.; Ramm, U.; Berg, H.; Kelbch, C.; Feng Jiazhen; Hagmann, S.; Kraft, G.; Ullrich, J.

    1991-01-01

    The δ-electron emission processes occuring in fast heavy ion atom collisons are explained qualitatively. The different spectral structures of electron emission arising from either the target or the projectile are explained in terms of simple models of the kinetics of momentum transfer induced by the COULOMB forces. In collisions of very heavy ions with matter, high nuclear COULOMB forces are created. These forces lead to a strong polarization of the electronic states of the participated electrons. The effects of this polarization are discussed. (orig.)

  13. The Enabling Delta Life Initiative - Global Programme of Action on Deltas - Programme description

    NARCIS (Netherlands)

    Driel, van W.F.; Skyllerstedt, S.; Wosten, J.H.M.

    2014-01-01

    Being ‘hotspots’ of human activity with generally high population densities, deltas are vulnerable to changes induced by a range of driving forces, both natural and anthropogenic. In addition to already existing challenges, uncertainty of the possible impacts of climate change, low lying deltas

  14. A model of water and sediment balance as determinants of relative sea level rise in contemporary and future deltas

    Science.gov (United States)

    Tessler, Zachary D.; Vörösmarty, Charles J.; Overeem, Irina; Syvitski, James P. M.

    2018-03-01

    Modern deltas are dependent on human-mediated freshwater and sediment fluxes. Changes to these fluxes impact delta biogeophysical functioning and affect the long-term sustainability of these landscapes for human and for natural systems. Here we present contemporary estimates of long-term mean sediment balance and relative sea level rise across 46 global deltas. We model scenarios of contemporary and future water resource management schemes and hydropower infrastructure in upstream river basins to explore how changing sediment fluxes impact relative sea level rise in delta systems. Model results show that contemporary sediment fluxes, anthropogenic drivers of land subsidence, and sea level rise result in delta relative sea level rise rates that average 6.8 mm/y. Assessment of impacts of planned and under-construction dams on relative sea level rise rates suggests increases on the order of 1 mm/y in deltas with new upstream construction. Sediment fluxes are estimated to decrease by up to 60% in the Danube and 21% in the Ganges-Brahmaputra-Meghna if all currently planned dams are constructed. Reduced sediment retention on deltas caused by increased river channelization and management has a larger impact, increasing relative sea level rise on average by nearly 2 mm/y. Long-term delta sustainability requires a more complete understanding of how geophysical and anthropogenic change impact delta geomorphology. Local and regional strategies for sustainable delta management that focus on local and regional drivers of change, especially groundwater and hydrocarbon extraction and upstream dam construction, can be highly impactful even in the context of global climate-induced sea level rise.

  15. Erratum dated 2014 June 25: Fate and Transport of Three Pharmaceuticals in the Sacramento-San Joaquin Delta

    Directory of Open Access Journals (Sweden)

    Minta M. Schaefer

    2013-06-01

    Full Text Available Pharmaceuticals and personal care products (PPCPs are found in surface waters worldwide. Wastewater treatment plant effluent is a major source of these contaminants. The Sacramento–San Joaquin Delta (Delta is a unique aquatic ecosystem, a source of drinking water for over 25 million Californians, and a primary source of water for Central Valley agriculture. The sharp decline of four pelagic fish species in the Delta in the last decade is just one of several indicators that the ecosystem is severely impaired. Several wastewater treatment plants (WWTPs discharge into the Delta, directly or through tributaries. The presence of PPCPs in the Delta has received very little attention relative to the immense effort underway to rehabilitate the ecosystem. This study determined concentrations of PPCPs in the Sacramento River in the vicinity of the Sacramento Regional Wastewater Treatment Plant using passive sampler monitoring. These data were used to estimate loads of three of the detected pharmaceuticals (carbamazepine, fluoxetine, and trimethoprim from nine other WWTPs that discharge to the Delta. The 2-D, finite element, Resource Management Associates (RMA Delta Model was then applied to determine the distribution that might result from these discharges. The model was run for the 2006, 2007, and 2009 water years. Results indicate that it is feasible that WWTP discharges could result in chronic presence of these pharmaceuticals at low ng L-1 levels at all 45 model output locations and, therefore, aquatic organisms within the Delta may be continually exposed to these contaminants.

  16. Building and Managing Electronic Resources in Digital Era in India with Special Reference to IUCAA and NIV, Pune: A Comparative Case Study

    Science.gov (United States)

    Sahu, H. K.; Singh, S. N.

    2015-04-01

    This paper discusses and presents a comparative case study of two libraries in Pune, India, Inter-University Centre for Astronomy and Astrophysics and Information Centre and Library of National Institute of Virology (Indian Council of Medical Research). It compares how both libraries have managed their e-resource collections, including acquisitions, subscriptions, and consortia arrangements, while also developing a collection of their own resources, including pre-prints and publications, video lectures, and other materials in an institutional repository. This study illustrates how difficult it is to manage electronic resources in a developing country like India, even though electronic resources are used more than print resources. Electronic resource management can be daunting, but with a systematic approach, various problems can be solved, and use of the materials will be enhanced.

  17. Lifetime improvement and beam stabilization by longitudinal phase modulation at the DELTA electron storage ring; Lebensdauerverbesserung und Strahlstabilisierung durch longitudinale Phasenmodulation am Elektronenspreicherring DELTA

    Energy Technology Data Exchange (ETDEWEB)

    Fuersch, Jonathan

    2014-10-16

    In DELTA especially at high beam currents often the occurence of an instability of a longitudinal oscillation mode is observed. In the framework of the present thesis first with different procedure the cause of the longitudinal oscillation mode, which is especially strongly excited at high beam currents, is searched for. Thereby connections between the occurrence of this mode and parameters from the region of the storage-ring high-frequency system is observed. It is shown by comparison of different procedures, simulation calculations, and experimental pre-examinations, that especially by a phase modulation of the storage-ring high frequency an essential improvement of especially the longitudinal beam stability and the beam lifetime can be reached. For the durable and reliable improvement of these beam properties in the framework of the present thesis a system for the longitudinal phase modulation of the after-acceleration voltage in the cavity resonator of the DELTA storage ring is concipated, developed, constructed, taken in operation, and tested. Finally the results aimed hereby are presented and discussed.

  18. Delta Electroproduction in 12-C

    Energy Technology Data Exchange (ETDEWEB)

    McLauchlan, Steven [Univ. of Glasgow, Scotland (United Kingdom)

    2003-01-01

    The Δ-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the Δ mass indicating that this potential is dependent on the momentum of the Δ. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the Δ resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4π acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the Δ mass was only observed in the exclusive measurements indicating that the Δ-nucleus potential is affected by the momentum of the Δ.

  19. Convex Relaxation of OPF in Multiphase Radial Networks with Wye and Delta Connections

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Changhong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Dall-Anese, Emiliano [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Low, Steven [California Institute of Technology

    2017-08-01

    This panel presentation focuses on multiphase radial distribution networks with wye and delta connections, and proposes a semidefinite relaxation of the AC optimal power flow (OPF) problem. Two multiphase power flow models are developed to facilitate the integration of delta-connected loads or generation resources in the OPF problem. The first model is referred to as the extended branch flow model (EBFM). The second model leverages a linear relationship between phase-to-ground power injections and delta connections that holds under a balanced voltage approximation (BVA). Based on these models, pertinent OPF problems are formulated and relaxed to semidefinite programs (SDPs). Numerical studies on IEEE test feeders show that the proposed SDP relaxations can be solved efficiently by a generic optimization solver. Numerical evidence also indicates that solving the resultant SDP under BVA is faster than under EBFM. Moreover, both SDP solutions are numerically exact with respect to voltages and branch flows. It is further shown that the SDP solution under BVA has a small optimality gap, and the BVA model is accurate in the sense that it reproduces actual system voltages.

  20. QCD in the {delta}-regime

    Energy Technology Data Exchange (ETDEWEB)

    Bietenholz, W. [Universidad Nacional Autonoma de Mexico, Mexico City (Mexico). Inst. de Ciencias Nucleares; Cundy, N. [Seoul National Univ. (Korea, Republic of). Lattice Gauge Theory Research Center; Goeckeler, M. [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Horsley, R.; Zanotti, J.M. [Edinburgh Univ. (United Kingdom). School of Physics; Nakamura, Y. [Tsukuba Univ., Ibaraki (Japan). Center for Computational Sciences; Pleiter, D. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany); Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Theoretical Physics Div.; Schierholz, G. [Regensburg Univ. (Germany). Inst. fuer Theoretische Physik; Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2011-03-15

    The {delta}-regime of QCD is characterised by light quarks in a small spatial box, but a large extent in (Euclidean) time. In this setting a specific variant of chiral perturbation theory - the {delta}-expansion - applies, based on a quantum mechanical treatment of the quasi onedimensional system. In particular, for vanishing quark masses one obtains a residual pion mass M{sup R}{sub {pi}}, which has been computed to the third order in the {delta}-expansion. A comparison with numerical measurements of this residual mass allows for a new determination of some Low Energy Constants, which appear in the chiral Lagrangian. We first review the attempts to simulate 2-flavour QCD directly in the {delta}-regime. This is very tedious, but results compatible with the predictions for M{sup R}{sub {pi}} have been obtained. Then we show that an extrapolation of pion masses measured in a larger volume towards the {delta}-regime leads to good agreement with the theoretical predictions. From those results, we also extract a value for the (controversial) sub-leading Low Energy Constant anti l{sub 3}. (orig.)

  1. Environmental legal implications of oil and gas exploration in the Niger Delta of Nigeria

    Science.gov (United States)

    Orubebe, Bibobra Bello

    Nigeria is an African country endowed with a wealth of oil and gas resources, and they are mainly found in the core Niger Delta (home to the Ijaw and Ogoni indigenous, ethnic minorities). Since Great Britain granted Nigeria political independence on October 1, 1960, successive Nigerian governments (military and civilian) have been dominated by the majority ethnic groups (Hausa-Fulani, Yoruba, and Ibo). Significantly, the government adopted a socialist-based model of absolute state ownership over oil and gas resources. The socialist model formed the basis of Nigeria's business collaboration with multinational oil and gas corporations from Europe and the United States (notably Shell, Chevron Texaco, Agip, Exxon Mobil, Total, and Elf). This model is fraught with contradictions and has led to unacceptable consequences, including policies that allow exploitation of natural resources without reference to environmental sustainability. When oil was first struck in 1956 at Oloibori (Ijaw area), people thought it would bring prosperity and an improved quality of life. Sadly, the opposite has occurred. Forty-nine years of hardship, agonizing pain, debilitating anger, extreme poverty, poisoned rivers, destroyed occupations, devastated environment, and stunted growth of the youth are the negative impacts of oil and gas exploitation in the Niger Delta. In other words, oil and gas exploration and production have visited a full range of evils---socio-political, economic, and cultural---upon the indigenous Niger Delta people. Furthermore, the wealth extracted from the area is used by the state and multinational corporations to enhance their own wealth and quality of life. Revenue has been conspicuously looted and misappropriated by political leaders at the expense of the Niger Delta environment and its people. This confluence of exploitation and injury has led to social upheavals and armed rebellions, all capable of precipitating the disintegration of the country. In this

  2. Delta Semantics Defined By Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kyng, Morten; Madsen, Ole Lehrmann

    and the possibility of using predicates to specify state changes. In this paper a formal semantics for Delta is defined and analysed using Petri nets. Petri nets was chosen because the ideas behind Petri nets and Delta concide on several points. A number of proposals for changes in Delta, which resulted from...

  3. Electronic structure of p type Delta doped systems

    International Nuclear Information System (INIS)

    Gaggero S, L.M.; Perez A, R.

    1998-01-01

    We summarize of the results obtained for the electronic structure of quantum wells that consist in an atomic layer doped with impurities of p type. The calculations are made within the frame worth of the wrapper function approach to independent bands and with potentials of Hartree. We study the cases reported experimentally (Be in GaAs and B in Si). We present the levels of energy, the wave functions and the rate of the electronic population between the different subbands, as well as the dependence of these magnitudes with the density of impurities in the layer. The participation of the bans of heavy holes is analysed, light and split-off band in the total electronic population. The effect of the temperature is discussed and we give a possible qualitative explanation of the experimental optical properties. (Author)

  4. Optimality and self-organization in river deltas

    Science.gov (United States)

    Tejedor, A.; Longjas, A.; Edmonds, D. A.; Zaliapin, I. V.; Georgiou, T. T.; Rinaldo, A.; Foufoula-Georgiou, E.

    2017-12-01

    Deltas are nourished by channel networks, whose connectivity constrains, if not drives, the evolution, functionality and resilience of these systems. Understanding the coevolution of deltaic channels and their flux organization is crucial for guiding maintenance strategies of these highly stressed systems from a range of anthropogenic activities. However, in contrast to tributary channel networks, to date, no theory has been proposed to explain how deltas self-organize to distribute water and sediment to the delta top and the shoreline. Here, we hypothesize the existence of an optimality principle underlying the self-organized partition of fluxes in delta channel networks. Specifically, we hypothesize that deltas distribute water and sediment fluxes on a given delta topology such as to maximize the diversity of flux delivery to the shoreline. By introducing the concept of nonlocal Entropy Rate (nER) and analyzing ten field deltas in diverse environments, we present evidence that supports our hypothesis, suggesting that delta networks achieve dynamically accessible maxima of their nER. Furthermore, by analyzing six simulated deltas using the Delf3D model and following their topologic and flux re-organization before and after major avulsions, we further study the evolution of nER and confirm our hypothesis. We discuss how optimal flux distributions in terms of nER, when interpreted in terms of resilience, are configurations that reflect an increased ability to withstand perturbations.

  5. Houtman Abrolhos Isotope (delta 18O, delta 13C) Data for 1795 to 1994

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — DESCRIPTION: VARIABLES AND UNITS: Column #1: core depth in mm Column #2: delta C-13 vs V-PDB Column #3: delta O-18 vs V-PDB Column #4: assigned date in years A.D....

  6. A new seamless, high-resolution digital elevation model of the San Francisco Bay-Delta Estuary, California

    Science.gov (United States)

    Fregoso, Theresa A.; Wang, Rueen-Fang; Ateljevich, Eli; Jaffe, Bruce E.

    2017-06-14

    Climate change, sea-level rise, and human development have contributed to the changing geomorphology of the San Francisco Bay - Delta (Bay-Delta) Estuary system. The need to predict scenarios of change led to the development of a new seamless, high-resolution digital elevation model (DEM) of the Bay – Delta that can be used by modelers attempting to understand potential future changes to the estuary system. This report details the three phases of the creation of this DEM. The first phase took a bathymetric-only DEM created in 2005 by the U.S. Geological Survey (USGS), refined it with additional data, and identified areas that would benefit from new surveys. The second phase began a USGS collaboration with the California Department of Water Resources (DWR) that updated a 2012 DWR seamless bathymetric/topographic DEM of the Bay-Delta with input from the USGS and modifications to fit the specific needs of USGS modelers. The third phase took the work from phase 2 and expanded the coverage area in the north to include the Yolo Bypass up to the Fremont Weir, the Sacramento River up to Knights Landing, and the American River up to the Nimbus Dam, and added back in the elevations for interior islands. The constant evolution of the Bay-Delta will require continuous updates to the DEM of the Delta, and there still are areas with older data that would benefit from modern surveys. As a result, DWR plans to continue updating the DEM.

  7. [Use of internet and electronic resources among Spanish intensivist physicians. First national survey].

    Science.gov (United States)

    Gómez-Tello, V; Latour-Pérez, J; Añón Elizalde, J M; Palencia-Herrejón, E; Díaz-Alersi, R; De Lucas-García, N

    2006-01-01

    Estimate knowledge and use habits of different electronic resources in a sample of Spanish intensivists: Internet, E-mail, distribution lists, and use of portable electronic devices. Self-applied questionnaire. A 50-question questionnaire was distributed among Spanish intensivists through the hospital marketing delegates of a pharmaceutical company and of electronic forums. A total of 682 questionnaires were analyzed (participation: 74%). Ninety six percent of those surveyed used Internet individually: 67% admitted training gap. Internet was the second source of clinical consultations most used (61%), slightly behind consultation to colleagues (65%). The pages consulted most were bibliographic databases (65%) and electronic professional journals (63%), with limited use of Evidence Based Medicine pages (19%). Ninety percent of those surveyed used e-mail regularly in the practice of their profession, although 25% admitted that were not aware of its possibilities. The use of E-mail decreased significantly with increase in age. A total of 62% of the intensivists used distribution lists. Of the rest, 42% were not aware of its existence and 32% admitted they had insufficient training to handle them. Twenty percent of those surveyed had portable electronic devices and 64% considered it useful, basically due to its rapid consultation at bedside. Female gender was a negative predictive factor of its use (OR 0.35; 95% CI 0.2-0.63; p=0.0002). A large majority of the Spanish intensivists use Internet and E-mail. E-mail lists and use of portable devices are still underused resources. There are important gaps in training and infrequent use of essential pages. There are specific groups that require directed educational policies.

  8. Model of e-learning with electronic educational resources of new generation

    OpenAIRE

    A. V. Loban; D. A. Lovtsov

    2017-01-01

    Purpose of the article: improving of scientific and methodical base of the theory of the е-learning of variability. Methods used: conceptual and logical modeling of the е-learning of variability process with electronic educational resource of new generation and system analysis of the interconnection of the studied subject area, methods, didactics approaches and information and communication technologies means. Results: the formalization complex model of the е-learning of variability with elec...

  9. Hydroclimatic mechanisms of cholera transmission in the Bengal Delta

    Science.gov (United States)

    Tretkoff, Ernie

    2011-07-01

    Cholera, a deadly waterborne disease, remains a major threat in many areas of the world, including the Bengal Delta region. In this region, cholera outbreaks have two annual peaks; the first occurs during the dry season in the spring, and the second occurs in the fall following the wet season. However, the large-scale hydroclimatic processes underlying the propagation of the disease have not been well understood. Akanda et al. show that cholera outbreaks in the Bengal Delta region propagate from the coast to inland and from spring to fall following two distinct transmission cycles. The first outbreak begins in the spring near the coast when northward movement of plankton-rich seawater and increasing salinity promote the growth of cholera-causing bacteria in rivers, which are used for irrigation, sanitation, and consumption. The second outbreak begins in the fall, after summer floods and monsoons affect sanitation conditions that aid in bacterial transmission by contaminating waters over much of Bangladesh. (Water Resources Research, doi:10.1029/ 2010WR009914, 2011)

  10. Triangulation, Emotional Reactivity, and Violence in the Niger Delta

    Directory of Open Access Journals (Sweden)

    Benjamin Aigbe Okonofua

    2013-04-01

    Full Text Available The Niger Delta conflict, for many years, was blamed on myriad forces, including greed, economic exploitation, pollution and ecological damage, resource appropriation and distribution disputes, ethno-religious antagonisms, poverty, unemployment, large-scale infrastructural deficits, corruption, militarization of oil producing communities and election processes, sociopolitical marginalization, cultism, and weapons proliferation. While all of these issues are important, they are not nearly as important as the deliberate roles played by high-level social, economic, and political interests who activated violence as a means to secure economic advantage from the delta’s oil industry. This study shines the light on this small, exclusive, and very powerful group whose actions triggered off the violence and yet are at the center of efforts to institute peace including the current disarmament, demobilization, and reintegration (DDR program. I argue that unless the contributions of these powerful interests are carefully teased out and the structures they have built to advantage themselves from the conflict are dismantled, peace will remain elusive in the Niger Delta.

  11. Turbidity and salinity affect feeding performance and physiological stress in the endangered delta smelt.

    Science.gov (United States)

    Hasenbein, Matthias; Komoroske, Lisa M; Connon, Richard E; Geist, Juergen; Fangue, Nann A

    2013-10-01

    delta smelt abundances in the low-salinity zone (0.5-6.0 ppt) of San Francisco Bay, a zone that is also understood to have optimal turbidities. By determining the responses of juvenile delta smelt to key abiotic factors, we hope to aid resource managers in making informed decisions in support of delta smelt conservation.

  12. Selfsimilar and fractal analysis of n-type delta-doped quasiregular GaAs quantum wells

    International Nuclear Information System (INIS)

    García-Cervantes, H.; Rodríguez-Vargas, I.

    2014-01-01

    We study the electronic structure of n-type delta-doped quantum wells in GaAs in which the multiple well system is built according to the Fibonacci sequence. The building blocks A and B correspond to delta-doped wells with impurities densities n 2DA and n 2DB , and the same well width. The Thomas-Fermi approximation, the semi-empirical sp 3 s* tight-binding model including spin, the Surface Green Function Matching method and the Transfer Matrix approach were implemented to obtain the confining potential, the electronic structure and the selfsimilarity of the spectrum. The fragmentation of the electronic spectra is observed whenever the building blocks A and B interact and it increases as the difference of impurities density between A and B increases as well. The wave function of the first sate of the fragmented bands presents critical characteristics, this is, it is not a localized state nor a extended one as well as it has selfsimilar features. So, the quasiregular characteristics are preserved irrespective of the complexity of the system and can affect the performance of devices based on these structures

  13. Selfsimilar and fractal analysis of n-type delta-doped quasiregular GaAs quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    García-Cervantes, H.; Rodríguez-Vargas, I. [Unidad Académica de Física, Universidad Autónoma de Zacatecas, Calzada Solidaridad Esquina Con Paseo La Bufa S/N, 98060 Zacatecas, Zac. (Mexico)

    2014-05-15

    We study the electronic structure of n-type delta-doped quantum wells in GaAs in which the multiple well system is built according to the Fibonacci sequence. The building blocks A and B correspond to delta-doped wells with impurities densities n{sub 2DA} and n{sub 2DB}, and the same well width. The Thomas-Fermi approximation, the semi-empirical sp{sub 3}s* tight-binding model including spin, the Surface Green Function Matching method and the Transfer Matrix approach were implemented to obtain the confining potential, the electronic structure and the selfsimilarity of the spectrum. The fragmentation of the electronic spectra is observed whenever the building blocks A and B interact and it increases as the difference of impurities density between A and B increases as well. The wave function of the first sate of the fragmented bands presents critical characteristics, this is, it is not a localized state nor a extended one as well as it has selfsimilar features. So, the quasiregular characteristics are preserved irrespective of the complexity of the system and can affect the performance of devices based on these structures.

  14. Oil, migration, and the political economy of HIV/AIDS prevention in Nigeria's Niger Delta.

    Science.gov (United States)

    Udoh, Isidore A

    2013-01-01

    In most of sub-Saharan Africa, HIV/AIDS is driven by endemic structural problems such as unemployment, poverty, forced migration, sexual exploitation, and concurrent sexual partnerships. In the Niger Delta of Nigeria, the epidemic is exacerbated by recurring regional conflict and negative environmental externalities resulting from 50 years of oil exploration. This article seeks to identify and analyze potential barriers to HIV/AIDS prevention and treatment from oil pollution and other environmental stressors in Nigeria's Niger Delta. We develop a conceptual framework to understand how oil politics and economic systems affect HIV risks in Nigeria. We then evaluate evidence of how environmental exposures can amplify risks. Using 10 semi-structured interviews, with 85 focus group participants, we test the argument that HIV transmission in the Niger Delta is related to a manipulative "divide and rule" power dynamic that characterizes multinational oil companies' role in shaping conflict contours in oil communities. Oil exploration destroys livelihoods, institutions, and values and forces impoverished and illiterate girls and women to migrate or be trafficked to urban centers as child laborers and sex workers. The elevated HIV/AIDS risk in the Niger Delta brings into focus the political economy of resource extraction, globalization, and indigenous, minority rights and struggles.

  15. Delta infection evidenced by radioimmunoanalysis in selected collectives

    Energy Technology Data Exchange (ETDEWEB)

    Kselikova, M; Horejsi, J; Urbankova, J

    1987-01-01

    The presence of the Delta agent within the population was tested by means of the Delta-antibody radioimmunoassay using competitive kits of the firms ABBOTT (ABBOTT-ANTI-DELTA) and SORIN (AB-DELTAK). The Delta-antibody was found in 3.2% HBV patients, 5% HBsAg carriers, and in 20.8% of specific anti-Hbs-immunoglobulin. In hemophiliacs and blood donors no Delta-antibody was seen.

  16. Delta infection evidenced by radioimmunoanalysis in selected collectives

    International Nuclear Information System (INIS)

    Kselikova, M.; Horejsi, J.; Urbankova, J.

    1987-01-01

    The presence of the Delta agent within the population was tested by means of the Delta-antibody radioimmunoassay using competitive kits of the firms ABBOTT (ABBOTT-ANTI-DELTA) and SORIN (AB-DELTAK). The Delta-antibody was found in 3.2% HBV patients, 5% HBsAg carriers, and in 20.8% of specific anti-Hbs-immunoglobulin. In hemophiliacs and blood donors no Delta-antibody was seen. (author)

  17. Electron cloud observations: a retrospective

    International Nuclear Information System (INIS)

    Harkay, K.

    2004-01-01

    A growing number of observations of electron cloud effects (ECEs) have been reported in positron and proton rings. Low-energy, background electrons ubiquitous in high-intensity particle accelerators. Amplification of electron cloud (EC) can occur under certain operating conditions, potentially giving rise to numerous effects that can seriously degrade accelerator performance. EC observations and diagnostics have contributed to a better understanding of ECEs, in particular, details of beam-induced multipacting and cloud saturation effects. Such experimental results can be used to provide realistic limits on key input parameters for modeling efforts and analytical calculations to improve prediction capability. Electron cloud effects are increasingly important phenomena in high luminosity, high brightness, or high intensity machines - Colliders, Storage rings, Damping rings, Heavy ion beams. EC generation and instability modeling increasingly complex and benchmarked against in situ data: (delta), (delta) 0 , photon reflectivity, and SE energy distributions important. Surface conditioning and use of solenoidal windings in field-free regions are successful cures: will they be enough? What are new observations and how do they contribute to body of work and understanding physics of EC?

  18. Recent Advances in Understanding Flow Dynamics and Transport of Water-Quality Constituents in the Sacramento–San Joaquin River Delta

    Directory of Open Access Journals (Sweden)

    David H. Schoellhamer

    2016-12-01

    Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art1This paper, part of the collection of research comprising the State of Bay–Delta Science 2016, describes advances during the past decade in understanding flow dynamics and how water-quality constituents move within California’s Sacramento–San Joaquin River Delta (Delta. Water-quality constituents include salinity, heat, oxygen, nutrients, contaminants, organic particles, and inorganic particles. These constituents are affected by water diversions and other human manipulations of flow, and they greatly affect the quantity and quality of benthic, pelagic, and intertidal habitat in the Delta. The Pacific Ocean, the Central Valley watershed, human intervention, the atmosphere, and internal biogeochemical processes are all drivers of flow and transport in the Delta. These drivers provide a conceptual framework for presenting recent findings. The tremendous expansion of acoustic and optical instruments deployed in the Delta over the past decade has greatly improved our understanding of how tidal variability affects flow and transport. Sediment is increasingly viewed as a diminishing resource needed to sustain pelagic habitat and tidal marsh, especially as sea level rises. Connections among the watershed, Delta, and San Francisco Bay that have been quantified recently highlight that a landscape view of this system is needed, rather than consideration of each region in isolation. We discuss interactions of multiple drivers and information gaps.

  19. Dermal absorption of the insecticide lindane (1 delta, 2 delta, 3 beta, 4 delta, 5 delta, 6 beta-hexachlorocyclohexane) in rats and rhesus monkeys: Effect of anatomical site

    International Nuclear Information System (INIS)

    Moody, R.P.; Ritter, L.

    1989-01-01

    Dermal absorption of the insecticide lindane (1 delta, 2 delta, 3 beta, 4 delta, 5 delta, 6 beta-hexachlorocyclohexane) was determined in rats and rhesus monkeys. Lindane is in widespread use as a 1% cream or lotion scabicide formulation and as a 1% miticide shampoo for body lice control in humans. Results obtained following our in vivo dermal absorption procedure demonstrated that 18 +/- 4.1%, 34 +/- 5.2%, and 54 +/- 26.3% of the applied dose was absorbed following topical applications at a rate of 1.5 micrograms/cm2 (6.2 micrograms/100 microliters of acetone) of the 14C-labeled pesticide to 4.2-cm2 regions of the forearm (n = 8), forehead (n = 7), and palm (n = 4) of rhesus monkeys, respectively. Dose sites were washed with soapy water 24 h posttreatment. Comparative studies in rats (n = 5) dosed middorsally demonstrated 31 +/- 9.5% absorption. Statistical analysis of the 14C excretion kinetics demonstrated slower clearance of lindane from rats than monkey forearm, forehead, or palm. Intramuscular (im) injections of 14C-lindane gave 52 +/- 7.1% recovery in monkey (n = 8) and 64 +/- 5.9% in rats (n = 5), suggesting body storage of this lipophilic chemical

  20. The influence of delta ferrite in the AISI 416 stainless steel hot workability

    International Nuclear Information System (INIS)

    Cardoso, P.H.S.; Kwietniewski, C.; Porto, J.P.; Reguly, A.; Strohaecker, T.R.

    2003-01-01

    Delta ferrite in martensitic stainless steels may have an adverse effect on the mechanical properties of these materials at high temperature. The occurrence of such phase is determined by the material chemical composition (mainly Cr and C), as-received microstructure condition and hot working temperature. The aim of this investigation is to assess the influence of delta ferrite on the hot workability of the martensitic AISI 416 stainless steel. Hence, different heats of this material (differing in chemical composition and as-received microstructure) were submitted to heating tests in order to observe the microstructural transformations that take place at high temperature and then examine the influence of these transformations on the mechanical behaviour. Phase characterisation and quantification were carried out using scanning electron microscopy/energy-dispersive X-ray microanalysis and image analysis. The heating tests were performed in the temperature range of 1100-1350 deg. C and hot workability in two heats with different delta ferrite content was assessed by hot torsion tests in the temperature range of 1000-1250 deg. C. The results have indicated that chemical composition and as-received microstructure strongly affect delta ferrite formation, which in turn deteriorates hot workability of the martensitic AISI 416 stainless steel

  1. Impact of Knowledge Resources Linked to an Electronic Health Record on Frequency of Unnecessary Tests and Treatments

    Science.gov (United States)

    Goodman, Kenneth; Grad, Roland; Pluye, Pierre; Nowacki, Amy; Hickner, John

    2012-01-01

    Introduction: Electronic knowledge resources have the potential to rapidly provide answers to clinicians' questions. We sought to determine clinicians' reasons for searching these resources, the rate of finding relevant information, and the perceived clinical impact of the information they retrieved. Methods: We asked general internists, family…

  2. Electronic Document Management: A Human Resource Management Case Study

    Directory of Open Access Journals (Sweden)

    Thomas Groenewald

    2004-11-01

    Full Text Available This case study serve as exemplar regarding what can go wrong with the implementation of an electronic document management system. Knowledge agility and knowledge as capital, is outlined against the backdrop of the information society and knowledge economy. The importance of electronic document management and control is sketched thereafter. The literature review is concluded with the impact of human resource management on knowledge agility, which includes references to the learning organisation and complexity theory. The intervention methodology, comprising three phases, follows next. The results of the three phases are presented thereafter. Partial success has been achieved with improving the human efficacy of electronic document management, however the client opted to discontinue the system in use. Opsomming Die gevalle studie dien as voorbeeld van wat kan verkeerd loop met die implementering van ’n elektroniese dokumentbestuur sisteem. Teen die agtergrond van die inligtingsgemeenskap en kennishuishouding word kennissoepelheid en kennis as kapitaal bespreek. Die literatuurstudie word afgesluit met die inpak van menslikehulpbronbestuur op kennissoepelheid, wat ook die verwysings na die leerorganisasie en kompleksietydsteorie insluit. Die metodologie van die intervensie, wat uit drie fases bestaan, volg daarna. Die resultate van die drie fases word vervolgens aangebied. Slegs gedeelte welslae is behaal met die verbetering van die menslike doeltreffendheid ten opsigte van elektroniese dokumentbestuur. Die klient besluit egter om nie voort te gaan om die huidige sisteem te gebruik nie.

  3. Determination of the positions and residues of the. delta. /sup + +/ and. delta. /sup 0/ poles. [Phase shifts,coulomb corrections

    Energy Technology Data Exchange (ETDEWEB)

    Vasan, S S [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics

    1976-04-19

    The poles and the associated residues in the ..pi..N P/sub 33/ amplitude corresponding to the resonances ..delta../sup + +/ and ..delta../sup 0/ are determined by fitting the ..pi../sup +/p and ..pi../sup -/p hadronic phase shifts from the Carter 73 analysis. The ..delta../sup + +/ and ..delta../sup 0/ pole positions are determined also from the nuclear phase shifts, these being the phase shifts made up of the hadronic phase shifts plus the Coulomb corrections. The pole positions obtained from the two sets of phase shifts are different, the differences being larger in the case of the ..delta../sup + +/.

  4. The Concentration Dependence of the (Delta)s Term in the Gibbs Free Energy Function: Application to Reversible Reactions in Biochemistry

    Science.gov (United States)

    Gary, Ronald K.

    2004-01-01

    The concentration dependence of (delta)S term in the Gibbs free energy function is described in relation to its application to reversible reactions in biochemistry. An intuitive and non-mathematical argument for the concentration dependence of the (delta)S term in the Gibbs free energy equation is derived and the applicability of the equation to…

  5. 78 FR 21491 - DeltaPoint Capital IV, L.P., DeltaPoint Capital IV (New York), L.P.; Notice Seeking Exemption...

    Science.gov (United States)

    2013-04-10

    ... SMALL BUSINESS ADMINISTRATION [License No. 02/02-0662, 02/02-0661] DeltaPoint Capital IV, L.P., DeltaPoint Capital IV (New York), L.P.; Notice Seeking Exemption Under Section 312 of the Small Business Investment Act, Conflicts of Interest Notice is hereby given that DeltaPoint Capital IV, L.P. and DeltaPoint...

  6. Mida pakub Delta? / Teele Kurm

    Index Scriptorium Estoniae

    Kurm, Teele

    2011-01-01

    Politsei- ja Piirivalveamet võtab kasutusele ühise Siseministeeriumi infotehnoloogia- ja arenduskeskuse ning Webmedia AS koostööna loodud dokumendihaldussüsteemi Delta. Kust sai Delta oma nime? Projekti "Dokumendihaldussüsteemi juurutamine Siseministeeriumi haldusalas" eesmärgid

  7. A Preliminary Assessment of Social Vulnerability in Ganga-Brahmaputra-Meghna Delta

    Science.gov (United States)

    Hazra, Sugata; Islam, Nabiul

    2017-04-01

    The Ganga-Brahmaputra-Meghna (GBM) Delta has a high population density and is exposed to rapid environmental changes making it one of the most stressed deltas in the world. The low-lying coastal areas of the Ganga-Brahmaputra-Meghna (GBM) Delta comprise 19 coastal districts of Bangladesh and two districts in India with significant land areas within 5 meters of sea level has a population of more than 50 million people at an average population density of 1100 people/km2. This population is exposed to a range of hazards such as severe cyclones, coastal erosion, and salinization, exacerbated by climate change and subsidence which imply severe stress on the resource dependent community of this region. This situation is further complicated by poverty and limited social well-being such as poor access to education/ health/ drinking water/ sanitation facilities, and lack of food and energy security. Thus assessing social vulnerability can help to understand which communities are susceptible to environmental change and guide adaptation actions to address these threats. This preliminary study aims to construct a socio-economic index by assessing the social vulnerability of coastal communities of GBM Delta taking consistent and common secondary data from the Census of India and the Bangladesh Bureau of Statisticsand applyinga Principle Component Analysis(PCA) methodology. Several statistical tests like Kaiser-Meyer-Olkin (KMO) have also been used to assess the appropriateness of using PCA. Among the selected common indicators, five major components are found to explain majority of the total variation of social vulnerability across the delta: (1) poverty, (2) dependency ratio, (3) agriculture dependency, (4) lack of sanitation and (5) existence of mud houses. The most important observation is the existence of a social vulnerability gradient across the coast. In other words, socially marginalised and vulnerable communities are found on the Delta margin in both India and

  8. Challenges in the implementation of an electronic surveillance system in a resource-limited setting: Alerta, in Peru

    Directory of Open Access Journals (Sweden)

    Soto Giselle

    2008-11-01

    Full Text Available Abstract Background Infectious disease surveillance is a primary public health function in resource-limited settings. In 2003, an electronic disease surveillance system (Alerta was established in the Peruvian Navy with support from the U.S. Naval Medical Research Center Detachment (NMRCD. Many challenges arose during the implementation process, and a variety of solutions were applied. The purpose of this paper is to identify and discuss these issues. Methods This is a retrospective description of the Alerta implementation. After a thoughtful evaluation according to the Centers for Disease Control and Prevention (CDC guidelines, the main challenges to implementation were identified and solutions were devised in the context of a resource-limited setting, Peru. Results After four years of operation, we have identified a number of challenges in implementing and operating this electronic disease surveillance system. These can be divided into the following categories: (1 issues with personnel and stakeholders; (2 issues with resources in a developing setting; (3 issues with processes involved in the collection of data and operation of the system; and (4 issues with organization at the central hub. Some of the challenges are unique to resource-limited settings, but many are applicable for any surveillance system. For each of these challenges, we developed feasible solutions that are discussed. Conclusion There are many challenges to overcome when implementing an electronic disease surveillance system, not only related to technology issues. A comprehensive approach is required for success, including: technical support, personnel management, effective training, and cultural sensitivity in order to assure the effective deployment of an electronic disease surveillance system.

  9. Civilizing the Conversation? Using Surveys to Inform Water Management and Science in the Sacramento-San Joaquin Delta

    Science.gov (United States)

    Hanak, E.; Phillips Chappelle, C.

    2013-12-01

    Improving ecosystem outcomes in California's Sacramento-San Joaquin Delta is a complex, high-stakes water resource management challenge. The Delta is a major hub for water supply conveyance and a valued ecological resource. Yet long-term declines in native fish populations have resulted in severe legal constraints on water exports and fueled growing public debates about the roles and responsibilities of flow modification and other sources of ecosystem stress. Meanwhile, scientific uncertainty, and the inability of the scientific community to effectively communicate what *is* known, has frustrated policymakers and encouraged 'combat science' - the commissioning and use of competing scientific opinions in the courtroom. This paper summarizes results from a study designed to inform the policy process through the use of confidential surveys of scientific researchers (those publishing in peer-reviewed journals, n=122) and engaged stakeholders and policymakers (n=240). The surveys, conducted in mid-2012, sought respondents' views on the sources of ecosystem stress and priority ecosystem management actions. The scientist survey is an example of the growing use of expert elicitation to address gaps in the scientific literature, particularly where there is uncertainty about priorities for decisionmaking (e.g., Cvitanovic et al. 2013, J. of Env. Mgmt; McDaniels et al. 2012, Risk Analysis). The stakeholder survey is a useful complement, enabling the identification of areas of consensus and divergence among stakeholder groups and between these groups and scientific experts. The results suggest such surveys are a promising tool for addressing complex water management problems. We found surprisingly high agreement among scientists on the relative roles of stressors and the most promising management actions; they emphasized restoring more natural processes through habitat and flow actions within the watershed, consistent with 'reconciliation ecology' approaches (Rosenzweig 2003

  10. Using Science Skills to Understand Ecophysiology and Manage Resources

    Science.gov (United States)

    Bubenheim, David

    2015-01-01

    Presentation will be for a general audience and focus on plant science and ecosystem science in NASA. Examples from the projects involving the presenter will be used to illustrate. Specifically, the California Sacramento-San Joaquin River Delta project. This collaboration supports the goals of the Delta Plan in developing science-based, adaptive-management strategies. The mission is to improve reliability of water supply and restore a healthy Delta ecosystem while enhancing agriculture and recreation. NASA can contribute gap-filling science understanding of overall functions in the Delta ecosystem and assess and help develop management plans for specific issues. Airborne and satellite remote-sensing, ecosystem modeling, and biological studies provide underlying data needed by Delta stakeholders to assess and address water, ecosystem restoration, and environmental and economic impacts of potential actions in the Delta. The California Sacramento-San Joaquin River Delta, the hub for California's water supply, supports important ecosystem services for fisheries, supplies drinking water for millions, and distributes water from Northern California to agriculture and urban communities to the south; millions of people and businesses depend on Delta water. Decades of competing demands for Delta resources and year-to-year variability in precipitation has resulted in diminished overall health of the Delta. Declines in fish populations, threatened ecosystems, endangered species, invasive plants and animals, cuts in agricultural exports, and increased water conservation is the result. NASA and the USDA, building on previous collaborations, aide local Delta stakeholders in assessing and developing an invasive weed management approach. Aquatic, terrestrial, and riparian invasive weeds threaten aquatic and terrestrial ecosystem restoration efforts. Aquatic weeds are currently detrimental economically, environmentally, and sociologically in the Delta. They negatively impact the

  11. Terrestrial Water Storage from GRACE and Satellite Altimetry in the Okavango Delta (Botswana)

    DEFF Research Database (Denmark)

    Andersen, Ole Baltazar; Krogh, Pernille Engelbredt; Bauer-Gottwein, Peter

    2010-01-01

    New technology can for the first time enable the accurate retrieval of the global and regional water budgets from space-borne and ground-based gravity surveys. Water is mankind’s most critical natural resource, but it is being heavily used throughout the globe. The aim of this paper is to outline...... the HYDROGRAV project dealing with improving large scale hydrological model with time variable gravity observations. Also preliminary HYDROGRAV investigationsa of terrestrial water storage variations in the Okavango delta in Botswana are presented. Data from 4 years of satellite altimetry, GRACE derived TWS...... and GLDAS hydrological model all show a clear annual variation corresponding to the well known seasonality of the delta. However, they also all show an increasing trend in the amount of water storage in the region over the last 4 years....

  12. Changes in the areal extents of the Athabasca River, Birch River, and Cree Creek Deltas, 1950-2014, Peace-Athabasca Delta, Canada

    Science.gov (United States)

    Timoney, Kevin; Lee, Peter

    2016-04-01

    Deltas form where riverborne sediment accumulates at the interface of river mouths and their receiving water bodies. Their areal extent is determined by the net effect of processes that increase their extent, such as sediment accumulation, and processes that decrease their extent, such as erosion and subsidence. Through sequential mapping and construction of river discharge and sediment histories, this study examined changes in the subaerial extents of the Cree Creek and Athabasca River Deltas (both on the Athabasca River system) and the Birch River Delta in northern Canada over the period 1950-2014. The purpose of the study was to determine how, when, and why the deltas changed in areal extent. Temporal growth patterns were similar across the Athabasca and Birch River systems indicative of a climatic signal. Little or no areal growth occurred from 1950 to 1968; moderate growth occurred between 1968 and the early to mid-1980s; and rapid growth occurred between 1992 and 2012. Factors that affected delta progradation included dredging, sediment supply, isostatic drowning, delta front bathymetry, sediment capture efficiency, and storms. In relation to sediment delivered, areal growth rates were lowest in the Athabasca Delta, intermediate in the Birch Delta, and highest in the Cree Creek Delta. Annual sediment delivery is increasing in the Cree Creek Delta; there were no significant trends in annual sediment delivery in the Birch and Athabasca Deltas. There was a lag of up to several years between sediment delivery events and progradation. Periods of delta progradation were associated with low water levels of the receiving basins. Predicted climate-change driven declines in river discharge and lake levels may accelerate delta progradation in the region. In the changing ecosystems of northeastern Alberta, inadequate monitoring of vegetation, landforms, and sediment regimes hampers the elucidation of the nature, rate, and causality of ecosystem changes.

  13. An analytical framework for strategic delta planning

    NARCIS (Netherlands)

    Seijger, C.; Douven, W.; Halsema, van G.; Hermans, L.; Evers, J.; Phi, H.L.; Khan, M.F.; Brunner, J.; Pols, L.; Ligtvoet, W.; Koole, S.; Slager, K.; Vermoolen, M.S.; Hasan, S.; Thi Minh Hoang, Vo

    2017-01-01

    Sectoral planning on water, agriculture and urban development has not been able to prevent increased flood risks and environmental degradation in many deltas. Governments conceive strategic delta planning as a promising planning approach and develop strategic delta plans. Such plans are linked to

  14. A QCQP Approach for OPF in Multiphase Radial Networks with Wye and Delta Connections: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zamzam, Ahmed, S.; Zhaoy, Changhong; Dall' Anesey, Emiliano; Sidiropoulos, Nicholas D.

    2017-06-27

    This paper examines the AC Optimal Power Flow (OPF) problem for multiphase distribution networks featuring renewable energy resources (RESs). We start by outlining a power flow model for radial multiphase systems that accommodates wye-connected and delta-connected RESs and non-controllable energy assets. We then formalize an AC OPF problem that accounts for both types of connections. Similar to various AC OPF renditions, the resultant problem is a non convex quadratically-constrained quadratic program. However, the so-called Feasible Point Pursuit-Successive Convex Approximation algorithm is leveraged to obtain a feasible and yet locally-optimal solution. The merits of the proposed solution approach are demonstrated using two unbalanced multiphase distribution feeders with both wye and delta connections.

  15. The Future of the Mississippi Delta: Shifting Baselines, Diminishing Resilience, and Growing Non-Sustainability

    Science.gov (United States)

    Day, J.

    2017-12-01

    Ecosystems and human communities of the Mississippi delta developed with predictable basin inputs, stable sea level, and as an open system with a high degree of interaction among drainage basin inputs, deltaic plain, and the coastal sea. Human activity changed altered the coast and lowered predictability. Management has become very energy intensive and dependent on cheap resources with more hard engineering and less ecological engineering. Pervasive alteration of the basin and delta and global change have altered the baseline and change is accelerating. Climate change projections include not only sea-level rise, but also more stronger hurricanes, increased large river floods, and more intense rainfall events and droughts. A sustainable Mississippi is outside of the boundaries of the current CMP.

  16. Natural disturbance shapes benthic intertidal macroinvertebrate communities of high latitude river deltas

    Science.gov (United States)

    Churchwell, Roy T.; Kendall, Steve J.; Blanchard, Amy L.; Dunton, Kenneth H.; Powell, Abby N.

    2016-01-01

    Unlike lower latitude coastlines, the estuarine nearshore zones of the Alaskan Beaufort Sea are icebound and frozen up to 9 months annually. This annual freezing event represents a dramatic physical disturbance to fauna living within intertidal sediments. The main objectives of this study were to describe the benthic communities of Beaufort Sea deltas, including temporal changes and trophic structure. Understanding benthic invertebrate communities provided a baseline for concurrent research on shorebird foraging ecology at these sites. We found that despite continuous year-to-year episodes of annual freezing, these estuarine deltas are populated by a range of invertebrates that represent both marine and freshwater assemblages. Freshwater organisms like Diptera and Oligochaeta not only survive this extreme event, but a marine invasion of infaunal organisms such as Amphipoda and Polychaeta rapidly recolonizes the delta mudflats following ice ablation. These delta sediments of sand, silt, and clay are fine in structure compared to sediments of other Beaufort Sea coastal intertidal habitats. The relatively depauperate invertebrate community that ultimately develops is composed of marine and freshwater benthic invertebrates. The composition of the infauna also reflects two strategies that make life on Beaufort Sea deltas possible: a migration of marine organisms from deeper lagoons to the intertidal and freshwater biota that survive the 9-month ice-covered period in frozen sediments. Stable isotopic analyses reveal that both infaunal assemblages assimilate marine and terrestrial sources of organic carbon. These results provide some of the first quantitative information on the infaunal food resources of shallow arctic estuarine systems and the long-term persistence of these invertebrate assemblages. Our data help explain the presence of large numbers of shorebirds in these habitats during the brief summer open-water period and their trophic importance to migrating

  17. Hydrogen is a preferred intermediate in the energy-conserving electron transport chain of Methanosarcina barkeri.

    Science.gov (United States)

    Kulkarni, Gargi; Kridelbaugh, Donna M; Guss, Adam M; Metcalf, William W

    2009-09-15

    Methanogens use an unusual energy-conserving electron transport chain that involves reduction of a limited number of electron acceptors to methane gas. Previous biochemical studies suggested that the proton-pumping F(420)H(2) dehydrogenase (Fpo) plays a crucial role in this process during growth on methanol. However, Methanosarcina barkeri Delta fpo mutants constructed in this study display no measurable phenotype on this substrate, indicating that Fpo plays a minor role, if any. In contrast, Delta frh mutants lacking the cytoplasmic F(420)-reducing hydrogenase (Frh) are severely affected in their ability to grow and make methane from methanol, and double Delta fpo/Delta frh mutants are completely unable to use this substrate. These data suggest that the preferred electron transport chain involves production of hydrogen gas in the cytoplasm, which then diffuses out of the cell, where it is reoxidized with transfer of electrons into the energy-conserving electron transport chain. This hydrogen-cycling metabolism leads directly to production of a proton motive force that can be used by the cell for ATP synthesis. Nevertheless, M. barkeri does have the flexibility to use the Fpo-dependent electron transport chain when needed, as shown by the poor growth of the Delta frh mutant. Our data suggest that the rapid enzymatic turnover of hydrogenases may allow a competitive advantage via faster growth rates in this freshwater organism. The mutant analysis also confirms the proposed role of Frh in growth on hydrogen/carbon dioxide and suggests that either Frh or Fpo is needed for aceticlastic growth of M. barkeri.

  18. Constraining Holocene Evolution of Shelf Bayhead Delta Deposits Offshore Mississippi, USA

    Science.gov (United States)

    Hollis, R. J.; Wallace, D. J.; Miner, M. D.

    2017-12-01

    level curves will be a valuable resource toward predicting future barrier island responses with accelerated SLR in the Gulf of Mexico by understanding the Holocene evolution of Petit Bois Island, adjacent bayhead deltas, and offshore sand shoals.

  19. Spatio-temporal distributions of delta18O, delta D and salinity in the Arabian Sea: Identifying processes and controls

    Digital Repository Service at National Institute of Oceanography (India)

    Deshpande, R.D; Muraleedharan, P.M.; Singh, R.L.; Kumar, B.; Rao, M.S.; Dave, M.; Sivakumar, K.U.; Gupta, S.K.

    the geographic distributions of the delta18O and S; (2) in spite of a large scatter, a statistically significant delta18O–S relationship can be identified in much of the investigated part of the AS; (3) the delta18Odelta...

  20. Considering Point-of-Care Electronic Medical Resources in Lieu of Traditional Textbooks for Medical Education.

    Science.gov (United States)

    Hale, LaDonna S; Wallace, Michelle M; Adams, Courtney R; Kaufman, Michelle L; Snyder, Courtney L

    2015-09-01

    Selecting resources to support didactic courses is a critical decision, and the advantages and disadvantages must be carefully considered. During clinical rotations, students not only need to possess strong background knowledge but also are expected to be proficient with the same evidence-based POC resources used by clinicians. Students place high value on “real world” learning and therefore may place more value on POC resources that they know practicing clinicians use as compared with medical textbooks. The condensed nature of PA education requires students to develop background knowledge and information literacy skills over a short period. One way to build that knowledge and those skills simultaneously is to use POC resources in lieu of traditional medical textbooks during didactic training. Electronic POC resources offer several advantages over traditional textbooks and should be considered as viable options in PA education.

  1. Changes in Ecosystem Services and related Livelihoods in the Mekong Delta: vulnerabilities and adaptation strategies

    Science.gov (United States)

    Sebesvari, Z.; Renaud, F. G.

    2014-12-01

    The Mekong Delta (Vietnam) is highly vulnerable to the many impacts of global environmental change as well as to the accelerating anthropogenic changes in the catchment and in the delta itself. Today the delta is an agricultural landscape controlled by engineering structures such as channels, dykes, embankments, and sluice gates. These structures have been constructed gradually over the last 200 years mainly for irrigation and flood control in the upper part of the delta and to control saline intrusion in the coastal areas. Recent changes in the hydrology mainly driven by upstream hydropower development on the mainstream and the tributaries of the Mekong will likely have far reaching impacts on the delta´s social-ecological systems through changes in e.g. sedimentation processes, nutrient transport as well as the health of aquatic ecosystems. Further threats to the delta include sea level rise and an increase in seasonal rainfall variability leading to an increase in flood variability. These changes affect the lives of millions of low-income inhabitants who depend on the ecosystem services provided by the Mekong for their livelihoods and sustenance. Since the changes in ecosystem service provision are occurring relatively fast while the resource dependency of the delta population is very high, adaptation becomes a challenge. An assessment of livelihood dependencies on ecosystem services requires an understanding of ecosystem services affected by different drivers of change, as well as of the types of livelihoods likely to be jeopardized as a result of these changes. We will present main ecosystem services supporting specific livelihoods, discuss how they are threatened, and analyse the merits of potential solutions. Options based solely on grey infrastructure might be problematic on the long term while an integration of ecosystem based solution such as a (re)adaptation of agricultural production systems to floods in the upper delta might be a more sustainable

  2. Adaptive Delta Management: cultural aspects of dealing with uncertainty

    Science.gov (United States)

    Timmermans, Jos; Haasnoot, Marjolijn; Hermans, Leon; Kwakkel, Jan

    2016-04-01

    Deltas are generally recognized as vulnerable to climate change and therefore a salient topic in adaptation science. Deltas are also highly dynamic systems viewed from physical (erosion, sedimentation, subsidence), social (demographic), economic (trade), infrastructures (transport, energy, metropolization) and cultural (multi-ethnic) perspectives. This multi-faceted dynamic character of delta areas warrants the emergence of a branch of applied adaptation science, Adaptive Delta Management, which explicitly focuses on climate adaptation of such highly dynamic and deeply uncertain systems. The application of Adaptive Delta Management in the Dutch Delta Program and its active international dissemination by Dutch professionals results in the rapid dissemination of Adaptive Delta Management to deltas worldwide. This global dissemination raises concerns among professionals in delta management on its applicability in deltas with cultural conditions and historical developments quite different from those found in the Netherlands and the United Kingdom where the practices now labelled as Adaptive Delta Management first emerged. This research develops an approach and gives a first analysis of the interaction between the characteristics of different approaches in Adaptive Delta Management and their alignment with the cultural conditions encountered in various delta's globally. In this analysis, first different management theories underlying approaches to Adaptive Delta Management as encountered in both scientific and professional publications are identified and characterized on three dimensions: The characteristics dimensions used are: orientation on today, orientation on the future, and decision making (Timmermans, 2015). The different underlying management theories encountered are policy analysis, strategic management, transition management, and adaptive management. These four management theories underlying different approaches in Adaptive Delta Management are connected to

  3. Complex rearrangements within the human J delta-C delta/J alpha-C alpha locus and aberrant recombination between J alpha segments

    NARCIS (Netherlands)

    Baer, R.; Boehm, T.; Yssel, H.; Spits, H.; Rabbitts, T. H.

    1988-01-01

    We have examined DNA rearrangements within a 120 kb cloned region of the human T cell receptor J delta-C delta/J alpha-C alpha locus. Three types of pattern emerge from an analysis of T cell lines and clones. Firstly, cells with two rearrangements within J delta-C delta; secondly, cells with one

  4. Information resources and access in Delta State University library ...

    African Journals Online (AJOL)

    It was revealed in the study that due to various internet hiccups and financial problems affecting library services the use of ICTs in information retrieval has not fully gain ed ground. Based on the findings, pertinent recommendations were made. Key Words: Information , Resources, Access, Library, University, Abraka , Nigeria ...

  5. Influence of habitat heterogeneity on anuran diversity in Restinga landscapes of the Parnaíba River delta, northeastern Brazil.

    Science.gov (United States)

    Araújo, Kássio C; Guzzi, Anderson; Ávila, Robson W

    2018-01-01

    Anurans have close associations with environmental conditions and therefore represent an interesting vertebrate group for examining how resource availability and environmental variables influence species diversity. Associations between habitat heterogeneity and anuran species diversity were tested in the Restinga landscapes of the Parnaíba River delta in northeastern Brazil. Twenty-one anuran species were sampled in the rainy season during monthly excursions (December 2015 to June 2016) into areas of Restinga on two islands in the Parnaíba River delta. The fourth highest anuran diversity was found in this type of environment in Brazil and is the third in northeastern Brazil. Microenvironments, characterized by a combination of vernal pools with different vegetational and physical structures, better explained anuran species composition in the Parnaíba River delta.

  6. Sediment and Vegetation Controls on Delta Channel Networks

    Science.gov (United States)

    Lauzon, R.; Murray, A. B.; Piliouras, A.; Kim, W.

    2016-12-01

    Numerous factors control the patterns of distributary channels formed on a delta, including water and sediment discharge, grain size, sea level rise rates, and vegetation type. In turn, these channel networks influence the shape and evolution of a delta, including what types of plant and animal life - such as humans - it can support. Previous fluvial modeling and flume experiments, outside of the delta context, have addressed how interactions between sediment and vegetation, through their influence on lateral transport of sediment, determine what type of channel networks develops. Similar interactions likely also shape delta flow patterns. Vegetation introduces cohesion, tending to reduce channel migration rates and strengthen existing channel banks, reinforcing existing channels and resulting in localized, relatively stable flow patterns. On the other hand, sediment transport processes can result in lateral migration and frequent switching of active channels, resulting in flow resembling that of a braided stream. While previous studies of deltas have indirectly explored the effects of vegetation through the introduction of cohesive sediment, we directly incorporate key effects of vegetation on flow and sediment transport into the delta-building model DeltaRCM to explore how these effects influence delta channel network formation. Model development is informed by laboratory flume experiments at UT Austin. Here we present initial results of experiments exploring the effects of sea level rise rate, sediment grain size, vegetation type, and vegetation growth rate on delta channel network morphology. These results support the hypothesis that the ability for lateral transport of sediment to occur plays a key role in determining the evolution of delta channel networks and delta morphology.

  7. Resource conservation approached with an appropriate collection and upgrade-remanufacturing for used electronic products.

    Science.gov (United States)

    Zlamparet, Gabriel I; Tan, Quanyin; Stevels, A B; Li, Jinhui

    2018-03-01

    This comparative research represents an example for a better conservation of resources by reducing the amount of waste (kg) and providing it more value under the umbrella of remanufacturing. The three discussed cases will expose three issues already addressed separately in the literature. The generation of waste electrical and electronic equipment (WEEE) interacts with the environmental depletion. In this article, we gave the examples of addressed issues under the concept of remanufacturing. Online collection opportunity eliminating classical collection, a business to business (B2B) implementation for remanufactured servers and medical devices. The material reuse (recycling), component sustainability, reuse (part harvesting), product reuse (after repair/remanufacturing) indicates the recovery potential using remanufacturing tool for a better conservation of resources adding more value to the products. Our findings can provide an overview of new system organization for the general collection, market potential and the technological advantages using remanufacturing instead of recycling of WEEE or used electrical and electronic equipment. Copyright © 2017. Published by Elsevier Ltd.

  8. Effects of the Use of Electronic Human Resource Management (EHRM Within Human Resource Management (HRM Functions at Universities

    Directory of Open Access Journals (Sweden)

    Chux Gervase Iwu

    2016-09-01

    Full Text Available This study set out to examine the effect of e-hrm systems in assisting human resource practitioners to execute their duties and responsibilities. In comparison to developed economies of the world, information technology adoption in sub-Saharan Africa has not been without certain glitches. Some of the factors that are responsible for these include poor need identification, sustainable funding, and insufficient skills. Besides these factors, there is also the issue of change management and users sticking to what they already know. Although, the above factors seem negative, there is strong evidence that information systems such as electronic human resource management present benefits to an organization. To achieve this, a dual research approach was utilized. Literature assisted immensely in both the development of the conceptual framework upon which the study hinged as well as in the development of the questionnaire items. The study also made use of an interview checklist to guide the participants. The findings reveal a mix of responses that indicate that while there are gains in adopting e-hrm systems, it is wiser to consider supporting resources as well as articulate the needs of the university better before any investment is made.

  9. Human Impacts On The Bengal Delta's Response To Rapid Climate And Sea-Level Changes: Who Threatens Whom? (Invited)

    Science.gov (United States)

    Goodbred, S. L.

    2009-12-01

    The densely populated country of Bangladesh is often cited as being severely threatened by predicted changes in climate and accelerated sea-level rise. Justification for this grave assessment is founded in part on the low-lying nation's frequent inundation by river floods and storm surges, which affect millions of people annually. Indeed, nearly 50% of the delta system lies natural environment it speaks more to a healthful future than decline. Here I present field-based observations of sediment dispersal in the modern Bengal delta, which demonstrate how the system may remain relatively stable over the next century. However, this potentially acceptable outcome becomes increasingly unlikely if human interferences are considered. For example, short-term strategies to mitigate flooding would likely involve artificial leveeing of the river and the diking of coastal lowlands, both of which would limit sedimentation and diminish relative elevation of the delta surface. Threats upstream of the delta also include river damming to address demands for hydroelectric power and water resources in India, with a resulting decline in sediment discharge to the coast. Ultimately, it may be the impacts of such direct human-modification to the Bengal delta and river systems that outpace - in time and severity - those resulting from climate and sea-level changes alone.

  10. Electronic human resource management: Enhancing or entrancing?

    Directory of Open Access Journals (Sweden)

    Paul Poisat

    2017-07-01

    Full Text Available Orientation: This article provides an investigation into the current level of development of the body of knowledge related to electronic human resource management (e-HRM by means of a qualitative content analysis. Several aspects of e-HRM, namely definitions of e-HRM, the theoretical perspectives around e-HRM, the role of e-HRM, the various types of e-HRM and the requirements for successful e-HRM, are examined. Research purpose: The purpose of the article was to determine the status of e-HRM and examine the studies that report on the link between e-HRM and organisational productivity. Motivation for the study: e-HRM has the capacity to improve organisational efficiency and leverage the role of human resources (HR as a strategic business partner. Main findings: The notion that the implementation of e-HRM will lead to improved organisational productivity is commonly assumed; however, empirical evidence in this regard was found to be limited. Practical/managerial implications: From the results of this investigation it is evident that more research is required to gain a greater understanding of the influence of e-HRM on organisational productivity, as well as to develop measures for assessing this influence. Contribution: This article proposes additional areas to research and measure when investigating the effectiveness of e-HRM. It provides a different lens from which to view e-HRM assessment whilst keeping it within recognised HR measurement parameters (the HR value chain. In addition, it not only provides areas for measuring e-HRM’s influence but also provides important clues as to how the measurements may be approached.

  11. ANALISIS SENSITIVITAS LINGKUNGAN OSCP (OIL SPILL CONTINGENCY PLAN DI PESISIR SELATAN DELTA MAHAKAM, PROVINSI KALIMANTAN TIMUR

    Directory of Open Access Journals (Sweden)

    Mursalin Mursalin

    2014-07-01

    Full Text Available The research was one part of oil spill contingency plan (OSCP developed for Delta Mahakam area, where oil & gas exploration and exploitation linked with rich biodiversity supporting coastal community livelihood. Environmental sensitivity  analysis for OSCP only do two early stages of OSCP scope, which integrated with the dangers of coastal vulnerability. This analysis mapped environmental component from oil pollution become sensitivity rangking as an effort to support response development strategies and priorities for the coastal resources protection. The aims of this research were (1 to establish environment sensitivity rank and (2 to identify primary factor supporting the environmental sensitivity for OSCP in south Delta Mahakam area. The result of analysis showed environmenal sensitivity was 62.37% (517.52 km, its mean very high sensitivity. Then the high sensitivity criteria was 11.31% (94 km. The criteria of medium sensitivity was 11.92% (99 km. While for low sensitivity and very low sensitivity respectively were 1.78% (15 km and 12.64% (105 km. Based on Principal Component Analysis (PCA, 36.01%  variability was explained by axis of factor 1. The others variability 18.53% and 13.93% were explained by axis of the factor 2 and factor 3. Axis of factor 1 for coastal exposure (EK, oil residence index (OR, coastal type (TP, and biological resources (SH had a quite large linear combinations coefficient, amounted to 0.94 (EK&OR, 0.83 (TP and 0.75 (SH. This indicated a very high contribution for environmental sensitivity OSCP level drafting. On axis of factor 2, the linear coeffisien combinations for the resource utilization of port (PL was 0.83 and settlement (PM was 0.85. Axis of factor 3 contributed 0.75 and 0.66 on migas platform (PO and placement of passive fishing gear/catchment area (AT. However, the utilization of coastal resources for PL, PM, PO and AT were on axis of factor 2 and factor 3 had a considerable distance with its SI variable

  12. Late quaternary evolution of the Orinoco Delta, Venezuela

    Science.gov (United States)

    Warne, A.G.; Guevara, E.H.; Aslan, A.

    2002-01-01

    The modern Orinoco Delta is the latest of a series of stacked deltas that have infilled the Eastern Venezuelan Basin (EVB) since the Oligocene. During the late Pleistocene sea-level lowstand (20,000 to 16,000 yrs BP), bedrock control points at the position of the present delta apex prevented the river channel from incising as deeply as many other major river systems. Shallow seismic data indicate that the late Pleistocene Orinoco incised into the present continental shelf, where it formed a braided-river complex that transported sediment to a series of shelf-edge deltas. As sea level rose from 16,000 to 9,500 yrs BP, the Orinoco shoreline shifted rapidly landward, causing shallow-marine waves and currents to form a widespread transgressive sand unit. Decelerating sea-level rise and a warmer, wetter climate during the early Holocene (9,500 to 6,000 yrs BP) induced delta development within the relatively quiet-water environment of the EVB embayment. Sea level approached its present stand in the middle Holocene (6,000 to 3,000 yrs BP), and the Orinoco coast prograded, broadening the delta plain and infilling the EVB embayment. Significant quantities of Amazon sediment began to be transported to the Orinoco coast by littoral currents. Continued progradation in the late Holocene caused the constriction at Boca de Serpientes to alter nearshore and shelf hydrodynamics and subdivide the submarine delta into two distinct areas: the Atlantic shelf and the Gulf of Paria. The increased influence of littoral currents along the coast promoted mudcape development. Because most of the water and sediment were transported across the delta plain through the Rio Grande distributary in the southern delta, much of the central and northwestern delta plain became sediment starved, promoting widespread accumulation of peat deposits. Human impacts on the delta are mostly associated with the Volca??n Dam on Can??o Manamo. However, human activities have had relatively little effect on the

  13. Water and nitrogen conditions affect the relationships of Delta13C and Delta18O to gas exchange and growth in durum wheat.

    Science.gov (United States)

    Cabrera-Bosquet, Llorenç; Molero, Gemma; Nogués, Salvador; Araus, José Luis

    2009-01-01

    Whereas the effects of water and nitrogen (N) on plant Delta(13)C have been reported previously, these factors have scarcely been studied for Delta(18)O. Here the combined effect of different water and N regimes on Delta(13)C, Delta(18)O, gas exchange, water-use efficiency (WUE), and growth of four genotypes of durum wheat [Triticum turgidum L. ssp. durum (Desf.) Husn.] cultured in pots was studied. Water and N supply significantly increased plant growth. However, a reduction in water supply did not lead to a significant decrease in gas exchange parameters, and consequently Delta(13)C was only slightly modified by water input. Conversely, N fertilizer significantly decreased Delta(13)C. On the other hand, water supply decreased Delta(18)O values, whereas N did not affect this parameter. Delta(18)O variation was mainly determined by the amount of transpired water throughout plant growth (T(cum)), whereas Delta(13)C variation was explained in part by a combination of leaf N and stomatal conductance (g(s)). Even though the four genotypes showed significant differences in cumulative transpiration rates and biomass, this was not translated into significant differences in Delta(18)O(s). However, genotypic differences in Delta(13)C were observed. Moreover, approximately 80% of the variation in biomass across growing conditions and genotypes was explained by a combination of both isotopes, with Delta(18)O alone accounting for approximately 50%. This illustrates the usefulness of combining Delta(18)O and Delta(13)C in order to assess differences in plant growth and total transpiration, and also to provide a time-integrated record of the photosynthetic and evaporative performance of the plant during the course of crop growth.

  14. Practicality of marine protected areas - Can there be solutions for the River Indus delta?

    Science.gov (United States)

    Kidwai, Samina; Fanning, Paul; Ahmed, Waqar; Tabrez, Mohsin; Zhang, Jing; Khan, Muhammad Wasim

    2016-12-01

    The River Indus delta is the most prominent feature on the Pakistan coast. Owing to its prominence, mangrove ecosystem, historical, ecological and economic significance it is also a proposed Marine Protected Area (MPA). Currently there are no designated MPAs in Pakistan. This paper presents findings of the Fishery Resource Appraisal Project of Pakistan (FRAPP) a fishery stock assessment carried out for the pelagic and demersal fishery resource of Pakistan from 2009 to 2015 and the Creek Survey Program (CSP) which was part of FRAPP. And discusses how the delta suffers from physical stress. The observations from FRAPP indicates deterioration in the mangrove ecosystem, that are evident in the form of loss of biodiversity and biological productivity. The 600 observations from 10 major creeks showed that trawl catches were a mix of generally small size fish and shrimp. Catches averaged less than 1 kg per tow in all the creeks sampled. Catch weights were somewhat higher in Isaro, WadiKhuddi, Paitiani, Dabbo, Richaal Creeks all of which were near mangrove areas and open sea. The most frequently occurring species of shrimps caught in the trawls belonged to 7 major taxa. The Khobar Creek and Upper Wari Creek are notable for the high rates of occurrence of every group except the Caridea. They are also the only two creeks where the freshwater family Paleomonidae is common. The size composition of the important penaeid family of shrimps in all study areas combined suggests that the smallest shrimps (0.5-1.5 cm carapace length CL) enter the creeks in February/March and adults (5-6 cm CL) move out again 6-12 months later. Four species of Penaeus (monodon, japonicus, semisulcatus, merguiensis), two species of Metapenaeus (monoceros, affinis), Parapeneoposis stylifera and Solenosera sp. were caught, all in low abundance, less than 0.5 Kg tow-1. The shrimp catches in the area off the Sindh coast, the catches averaged 4.30 ± 13.40 kg h-1 on the inner shelf (20-50 m) and 1.7 ± 6

  15. Economic Resource and Political Stability: The Niger Delta Quagmire

    African Journals Online (AJOL)

    The issue ofresource agitation has continued to generate serious concerns and discussions in Nigeria. In fact, the spillage emanating from this tends to spread across the boundaries of Nigeria as a result of the implications it bears on the oil industry and the industrial life line of western nations and their allies. The resource ...

  16. Identifying and evaluating electronic learning resources for use in adult-gerontology nurse practitioner education.

    Science.gov (United States)

    Thompson, Hilaire J; Belza, Basia; Baker, Margaret; Christianson, Phyllis; Doorenbos, Ardith; Nguyen, Huong

    2014-01-01

    Enhancing existing curricula to meet newly published adult-gerontology advanced practice registered nurse (APRN) competencies in an efficient manner presents a challenge to nurse educators. Incorporating shared, published electronic learning resources (ELRs) in existing or new courses may be appropriate in order to assist students in achieving competencies. The purposes of this project were to (a) identify relevant available ELR for use in enhancing geriatric APRN education and (b) to evaluate the educational utility of identified ELRs based on established criteria. A multilevel search strategy was used. Two independent team members reviewed identified ELR against established criteria to ensure utility. Only resources meeting all criteria were retained. Resources were found for each of the competency areas and included formats such as podcasts, Web casts, case studies, and teaching videos. In many cases, resources were identified using supplemental strategies and not through traditional search or search of existing geriatric repositories. Resources identified have been useful to advanced practice educators in improving lecture and seminar content in a particular topic area and providing students and preceptors with additional self-learning resources. Addressing sustainability within geriatric APRN education is critical for sharing of best practices among educators and for sustainability of teaching and related resources. © 2014.

  17. Systematic review of electronic surveillance of infectious diseases with emphasis on antimicrobial resistance surveillance in resource-limited settings.

    Science.gov (United States)

    Rattanaumpawan, Pinyo; Boonyasiri, Adhiratha; Vong, Sirenda; Thamlikitkul, Visanu

    2018-02-01

    Electronic surveillance of infectious diseases involves rapidly collecting, collating, and analyzing vast amounts of data from interrelated multiple databases. Although many developed countries have invested in electronic surveillance for infectious diseases, the system still presents a challenge for resource-limited health care settings. We conducted a systematic review by performing a comprehensive literature search on MEDLINE (January 2000-December 2015) to identify studies relevant to electronic surveillance of infectious diseases. Study characteristics and results were extracted and systematically reviewed by 3 infectious disease physicians. A total of 110 studies were included. Most surveillance systems were developed and implemented in high-income countries; less than one-quarter were conducted in low-or middle-income countries. Information technologies can be used to facilitate the process of obtaining laboratory, clinical, and pharmacologic data for the surveillance of infectious diseases, including antimicrobial resistance (AMR) infections. These novel systems require greater resources; however, we found that using electronic surveillance systems could result in shorter times to detect targeted infectious diseases and improvement of data collection. This study highlights a lack of resources in areas where an effective, rapid surveillance system is most needed. The availability of information technology for the electronic surveillance of infectious diseases, including AMR infections, will facilitate the prevention and containment of such emerging infectious diseases. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  18. Initial isotopic geochemistry ({delta} 18 O, {delta} D) of fluids from wells of the Los Humeros, Pue., geothermal field; Geoquimica isotopica ({delta} 18 O, {delta} D) inicial de fluidos de pozos del campo geotermico de Los Humeros, Pue.

    Energy Technology Data Exchange (ETDEWEB)

    Barragan Reyes, Rosa Maria; Arellano Gomez, Victor Manuel [Instituto de Investigaciones Electricas, Gerencia de Geotermia, Cuernavaca, Morelos (Mexico)]. E-mail: rmb@iie.org.mx; Ramirez Montes, Miguel; Tovar Aguado, Rigoberto [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Morelia, Michoacan (Mexico)

    2010-01-15

    Isotopic data ({delta} 18 O, {delta} D) from fluids from production wells at the Los Humeros, Pue., geothermal field were analyzed to investigate the possible origin of these fluids and the dominant processes of the reservoir at its initial state. According to pre-exploitation data, it is suggested the Los Humeros reservoir fluids are made of a mixture of meteoric water of very light isotopic composition (paleo-fluids) and andesitic water. The relationship {delta} D vs {delta} 18 O from pre-exploitation data indicates the produced fluids are composed of a mixture of (at least) two fluids with distinct isotopic compositions. At the more enriched end of the mixing relationship are the isotopic compositions of the wells H-23 and H-18 (located in the southern area of the field), while the lighter fluids were found in well H-16 (originally) and then in well H-16 (repaired). It was found that the liquid phases of deep wells are more enriched in {delta} 18 O while the shallow wells present lower values, suggesting a convection process at the initial state. Based on this isotopic profile, it is considered that even the production depths of the wells H-1, H-12 and H-16 (repaired) are just about the same, but their respective isotopic compositions are quite different. The {delta} 18 O value for well H-16 (repaired) seems to be that of condensate steam, while the corresponding values for wells H-1 and H-12 fall within the value interval of the deep wells (H-23). This suggests wells H-1 and H-12 are collecting very deep fluids enriched in {delta} 18 O. These results could be useful in creating a conceptual model of the reservoir. [Spanish] Se analizaron datos isotopicos ({delta}18 O, {delta}D) de los fluidos de pozos productores del campo geotermico de Los Humeros, Pue., para investigar el posible origen de los fluidos asi como los procesos dominantes del yacimiento en su estado inicial. De acuerdo con datos previos a la explotacion, se plantea que los fluidos del yacimiento

  19. Conceptualizing delta forms and processes in Arctic coastal environments

    DEFF Research Database (Denmark)

    Bendixen, Mette; Kroon, Aart

    2017-01-01

    Climate warming in the Arctic directly causes two opposite changes in Arctic coastal systems: increased melt-water discharge through rivers induces extra influx of sediments and extended open water season increases wave impact which reworks and erodes the shores. A shoreline change analysis along...... and popped up as hotspots. The Tuapaat delta and Skansen delta showed large progradation rates (1.5 and 7m/yr) and migration of the adjacent barriers and spits. The dynamic behavior at the delta mouths was mainly caused by classic delta channel lobe switching at one delta (Tuapaat), and by a breach...... of the fringing spit at the other delta (Skansen). The longshore and cross-shore transports are responsible for reworking the sediment with a result of migrating delta mouths and adjacent subaqueous mouth bars. Seaward progradation of the deltas is limited due to the steep nature of the bathymetry in Disko Bay...

  20. Assessment of environmental change and its socio-economic impacts in the mangrove ecological zone of the Niger Delta, Nigeria

    Science.gov (United States)

    James, Godstime Kadiri

    The Niger Delta, located in the central part of Southern Nigeria, is endowed with immense Mangrove resources, estimated to be the fourth largest in the world. The term Mangrove refers to salt tolerant species of trees or shrubs that grow on shores and in estuaries located in the coastal tropics and sub-tropical regions of the world. They support highly productive marine food chains. However, Mangrove ecosystems are in serious decline around the world due to the rapid increase in maritime commerce and exploration of mineral resources in the last few decades. These pressures often have immediate consequences on sensitive coastal environments and can potentially impact future human use of coastal space and resources. This dynamic process presents unique opportunities for research to explore the nature and consequences of these pressures. This dissertation focused on the Mangrove ecological zone of the Niger Delta, where resource exploitation and indigenous use of the environment are in direct conflict with important socio-economic implications. Environmental accounting metrics derived from the Driver-Pressure-State-Impact-Response (DPSIR) framework were used to assess changes in the spatial extent of the Niger Delta Mangrove ecosystem and the socio-economic impacts of the observed changes. Landsat remotely sensed satellite data from the mid-1980s through 2003 was used to assess change in the spatial extent of the Mangrove vegetation in the region. A total of 21,340 hectares of Mangrove forest was determined to be lost over the study period. Field research in the region confirmed that this loss was primarily driven by urbanization and activities of the multinational oil and gas corporations operating in the region. To estimate the socio-economic impacts of the Mangrove loss in the region, neoclassical economic valuation and participatory social valuation approaches were adopted. Results from the economic valuation revealed that the net present value of future income

  1. Conflicts Related to Natural Resources Exploitation: A Case Study of ...

    African Journals Online (AJOL)

    Conflicts Related to Natural Resources Exploitation: A Case Study of Oil Crisis in Nigeria's Niger Delta Region and its Socio-Political and Economic Implications. ... on the environment leading to pollution of land, rivers, creeks and waterways.

  2. Using ground-based geophysics to constrain the interpretation of airborne TEM data recorded across the Okavango Delta, Botswana

    Science.gov (United States)

    Podgorski, J. E.; Kalscheuer, T.; Doetsch, J.; Rabenstein, L.; Tshoso, G.; Meier, P.; Horstmeyer, H.; Kgotlhang, L.; Ploug, C.; Auken, E.; Kinzelbach, W. K.; Green, A. G.

    2011-12-01

    The Okavango Delta in northern Botswana is a near endorheic inland delta that has developed over the past ~2 MA in an active graben at the southwestern end of the East Africa Rift System. An annual flood from the north causes a slowly flowing surface water regime in the delta, but previous wetter climatic periods were responsible for intermittent lacustrine environments. The Okavango Delta is the largest permanent water body in the Kalahari Desert and, as such, represents an important resource for wildlife and humans alike. An airborne time-domain electromagnetic (TEM) survey, commissioned by the Botswana government, was undertaken in 2007 for the purpose of better understanding the hydrogeology of the delta. Initial processing and inversion of these data show within the main fan of the delta a resistive 20-50 m thick surface layer underlain by a 30-200 m thick conductive layer. In the upper fan, the conductive layer is underlain by a resistive unit beginning at about 150 m depth. This unit exhibits a dendritic pattern implying a fluvial origin. To help interpret this and other structures, geophysical field work was initiated in early 2011 at various locations in the delta. Seismic reflection and refraction, electrical resistive tomography (ERT), and ground TEM methods were employed. The seismic methods are useful for delineating the boundaries of the weathering and basement layers, whereas ERT provides an independent estimate of the resistivity structure, particularly at shallow depths. Ground TEM allows for a direct comparison with the airborne TEM soundings, helping to estimate the accuracy of the latter. Though still evolving, the current large-scale hydrogeological interpretation of the airborne data set includes a fresh water-saturated surface layer underlain by a saline aquifer and clay aquitard. In the upper fan of the delta, a fresh water aquifer appears to lie between the aquitard and the basement rock.

  3. From Millennium ERM to Proquest 360 Resource Manager: Implementing a new Electronic Resources Management System ERMS in an International Graduate Research University in Saudi Arabia

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    An overview of the Recommendation Study and the subsequent Implementation of a new Electronic Resources Management system ERMS in an international graduate research university in the Kingdom of Saudi Arabia. It covers the timeline, deliverables

  4. Adaptive delta management : Roots and branches

    NARCIS (Netherlands)

    Timmermans, J.S.; Haasnoot, M.; Hermans, L.M.; Kwakkel, J.H.; Rutten, M.M.; Thissen, W.A.H.

    2015-01-01

    Deltas are generally recognized as vulnerable to climate change and therefore a salient topic in adaptation science. Deltas are also highly dynamic systems viewed from physical (erosion, sedimentation, subsidence), social (demographic), economic (trade), infrastructures (transport, energy,

  5. Adaptive Delta Management : Roots and Branches

    NARCIS (Netherlands)

    Timmermans, Jos; Haasnoot, Marjolijn; Hermans, Leon; Kwakkel, Jan H.; Rutten, Maarten; Thissen, Wil A.H.; Mynett, Arthur

    2015-01-01

    Deltas are generally recognized as vulnerable to climate change and therefore a salient topic in adaptation science. Deltas are also highly dynamic systems viewed from physical (erosion, sedimentation, subsidence), social (demographic), economic (trade), infrastructures (transport, energy,

  6. The dynamics of central Main Ethiopian Rift waters: Evidence from {delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr ratios

    Energy Technology Data Exchange (ETDEWEB)

    Rango, Tewodros, E-mail: tewodros.godebo@duke.edu [Division of Earth and Ocean Sciences, Nicholas School of the Environment, Duke University, Durham, NC 27708 (United States)] [Addis Ababa University, Department of Earth Sciences, P.O. Box 1176, Addis Ababa (Ethiopia); Petrini, Riccardo; Stenni, Barbara [University of Trieste, Department of Geosciences, Via Weiss 1, I-34100 Trieste (Italy); Bianchini, Gianluca [Istituto di Geoscienze e Georisorse-CNR, Pisa (Italy)] [Department of Earth Sciences, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Slejko, Francesca [University of Trieste, Department of Geosciences, Via Weiss 1, I-34100 Trieste (Italy); Beccaluva, Luigi [Department of Earth Sciences, University of Ferrara, Via Saragat 1, 44100 Ferrara (Italy); Ayenew, Tenalem [Addis Ababa University, Department of Earth Sciences, P.O. Box 1176, Addis Ababa (Ethiopia)

    2010-12-15

    Research highlights: {yields} Chemical and isotope ({delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr) techniques are applied to understand various hydrological processes in the Main Ethiopian Rift. {yields} Some of the studied groundwaters display a depleted {delta}D-{delta}{sup 18}O composition when compared to the present-day average precipitation, thus suggesting that the rift floor aquifers also contains paleo-meteoric waters recharge associated with deep flow system. {yields} The pristine waters coming from the highlands display isotopic compositions characterized by less radiogenic {sup 87}Sr/{sup 86}Sr (and more depleted {delta}D, {delta}{sup 18}O). This isotopic signature subsequently evolves towards higher {sup 87}Sr/{sup 86}Sr by an interaction with the more radiogenic rhyolites of the rift and their weathered and redeposited products. - Abstract: Water samples from cold and geothermal boreholes, hot springs, lakes and rivers were analyzed for {delta}D, {delta}{sup 18}O and {sup 87}Sr/{sup 86}Sr compositions in order to investigate lake water-groundwater mixing processes, water-rock interactions, and to evaluate groundwater flow paths in the central Main Ethiopian Rift (MER) of the Ziway-Shala basin. Different ranges of isotopic values were recorded for different water types: hot springs show {delta}{sup 18}O -3.36 to +3.69 and {delta}D -15.85 to +24.23, deep Aluto-Langano geothermal wells show {delta}{sup 18}O -4.65 to -1.24 and {delta}D -12.39 to -9.31, groundwater wells show {delta}{sup 18}O -3.99 to +5.14 and {delta}D -19.69 to +32.27, whereas the lakes show {delta}{sup 18}O and {delta}D in the range +3.98 to +7.92 and +26.19 to +45.71, respectively. The intersection of the Local Meteoric Water Line (LMWL: {delta}D = 7 {delta}{sup 18}O + 11.2, R{sup 2} = 0.94, n = 42) and the Local Evaporation Line (LEL: {delta}D = 5.63{delta}{sup 18}O + 8, n = 14, R{sup 2} = 0.82) was used to estimate the average isotopic composition of recharge water into the

  7. delta 6 Hexadecenoic acid is synthesized by the activity of a soluble delta 6 palmitoyl-acyl carrier protein desaturase in Thunbergia alata endosperm.

    Science.gov (United States)

    Cahoon, E B; Cranmer, A M; Shanklin, J; Ohlrogge, J B

    1994-11-04

    delta 6 Hexadecenoic acid (16:1 delta 6) composes more than 80% of the seed oil of Thunbergia alata. Studies were conducted to determine the biosynthetic origin of the double bond of this unusual fatty acid. Assays of fractions of developing T. alata seed endosperm with [1-14C]palmitoyl (16:0)-acyl carrier protein (ACP) revealed the presence of a soluble delta 6 desaturase activity. This activity was greatest when 16:0-ACP was provided as a substrate, whereas no desaturation of the coenzyme A ester of this fatty acid was detected. In addition, delta 6 16:0-ACP desaturase activity in T. alata endosperm extracts was dependent on the presence of ferredoxin and molecular oxygen and was stimulated by catalase. To further characterize this enzyme, a cDNA encoding a diverged acyl-ACP desaturase was isolated from a T. alata endosperm cDNA library using polymerase chain reaction with degenerate oligonucleotides corresponding to conserved amino acid sequences in delta 9 stearoyl (18:0)- and delta 4 16:0-ACP desaturases. The primary structure of the mature peptide encoded by this cDNA shares 66% identity with the mature castor delta 9 18:0-ACP desaturase and 57% identity with the mature coriander delta 4 16:0-ACP desaturase. Extracts of Escherichia coli that express the T. alata cDNA catalyzed the delta 6 desaturation of 16:0-ACP. These results demonstrate that 16:1 delta 6 in T. alata endosperm is formed by the activity of a soluble delta 6 16:0-ACP desaturase that is structurally related to the delta 9 18:0- and delta 4 16:0-ACP desaturases. Implications of this work to an understanding of active site structures of acyl-ACP desaturases are discussed.

  8. Migration in Vulnerable Deltas: A Research Strategy

    Science.gov (United States)

    Hutton, C.; Nicholls, R. J.; Allan, A.

    2015-12-01

    C. Hutton1, & R. J. Nicholls1, , 1 University of Southampton, University Road, Southampton, Hampshire, United Kingdom, SO17 1BJ. cwh@geodata. soton.ac.ukAbstractGlobally, deltas contain 500 million people and with rising sea levels often linked to large number of forced migrants are expected in the coming century. However, migration is already a major process in deltas, such as the growth of major cities such as Dhaka and Kolkata. Climate and environmental change interacts with a range of catchment and delta level drivers, which encompass a nexus of sea-level rise, storms, freshwater and sediment supply from the catchment, land degradation, subsidence, agricultural loss and socio-economic stresses. DECCMA (Deltas, Vulnerability and Climate Change: Migration and Adaptation/CARRIA) is investigating migration in the Ganges-Brahmaputra-Meghna (GBM), Mahanadi and Volta Deltas, including the influence of climate change. The research will explore migration from a range of perspectives including governance and stakeholder analysis, demographic analysis, household surveys of sending and receiving areas, macro-economic analysis, and hazards and hotspot analysis both historically and into the future. Migration under climate change will depend on other adaptation in the deltas and this will be examined. Collectively, integrated analysis will be developed to examine migration, other adaptation and development pathways with a particular focus on the implications for the poorest. This will require the development of input scenarios, including expert-derived exogenous scenarios (e.g., climate change) and endogenous scenarios of the delta developed in a participatory manner. This applied research will facilitate decision support methods for the development of deltas under climate change, with a focus on migration and other adaptation strategies.

  9. Upper-division student difficulties with the Dirac delta function

    Directory of Open Access Journals (Sweden)

    Bethany R. Wilcox

    2015-03-01

    Full Text Available The Dirac delta function is a standard mathematical tool that appears repeatedly in the undergraduate physics curriculum in multiple topical areas including electrostatics, and quantum mechanics. While Dirac delta functions are often introduced in order to simplify a problem mathematically, students still struggle to manipulate and interpret them. To characterize student difficulties with the delta function at the upper-division level, we examined students’ responses to traditional exam questions and a standardized conceptual assessment, and conducted think-aloud interviews. Our analysis was guided by an analytical framework that focuses on how students activate, construct, execute, and reflect on the Dirac delta function in the context of problem solving in physics. Here, we focus on student difficulties using the delta function to express charge distributions in the context of junior-level electrostatics. Common challenges included invoking the delta function spontaneously, translating a description of a charge distribution into a mathematical expression using delta functions, integrating 3D or non-Cartesian delta function expressions, and recognizing that the delta function can have units. We also briefly discuss implications of these difficulties for instruction.

  10. Delta-nucleus dynamics: proceedings of symposium

    Energy Technology Data Exchange (ETDEWEB)

    Lee, T.S.H.; Geesaman, D.F.; Schiffer, J.P. (eds.)

    1983-10-01

    The appreciation of the role in nuclear physics of the first excited state of the nucleon, the delta ..delta..(1232), has grown rapidly in the past decade. The delta resonance dominates nuclear reactions induced by intermediate energy pions, nucleons, and electromagnetic probes. It is also the most important non-nucleonic degree of freedom needed to resolve many fundamental problems encountered in the study of low-energy nuclear phenomena. Clearly, a new phase of nuclear physics has emerged and conventional thinking must be extended to account for this new dimension of nuclear dynamics. The most challenging problem we are facing is how a unified theory can be developed to describe ..delta..-nucleus dynamics at all energies. In exploring this new direction, it is important to have direct discussions among researchers with different viewpoints. Separate entries were prepared for the 49 papers presented. (WHK)

  11. On the origin of delta spots

    International Nuclear Information System (INIS)

    Tang, F.

    1983-01-01

    Mount Wilson sunspot drawings from 1966 through 1980 were used in conjunction with Hα filtergrams from Big Bear Solar Observatory to examine the origin of delta spots, spots with bipolar umbrae within one penumbra. Of the six cases we studied, five were formed by the union of non-paired spots. They are either shoved into one another by two neighboring growing bipoles or by a new spot born piggy-back style on an existing spot of opposite polarity. Proper motions of the growing spots take on curvilinear paths around one another to avoid a collision. This is the shear motion observed in delta spots (Tanaka, 1979). In the remaining case, the delta spot was formed by spots that emerged as a pair. Our findings indicate no intrinsic differences in the formation or the behavior between delta spots of normal magnetic configuration. (orig.)

  12. Holocene evolution of the western Orinoco Delta, Venezuela

    Science.gov (United States)

    Aslan, A.; White, W.A.; Warne, A.G.; Guevara, E.H.

    2003-01-01

    The pristine nature of the Orinoco Delta of eastern Venezuela provides unique opportunities to study the geologic processes and environments of a major tropical delta. Remote-sensing images, shallow cores, and radiocarbon-dating of organic remains form the basis for describing deltaic environments and interpreting the Holocene history of the delta. The Orinoco Delta can be subdivided into two major sectors. The southeast sector is dominated by the Rio Grande-the principal distributary-and complex networks of anastomosing fluvial and tidal channels. The abundance of siliciclastic deposits suggests that fluvial processes such as over-bank flooding strongly influence this part of the delta. In contrast, the northwest sector is represented by few major distributaries, and overbank sedimentation is less widespread relative to the southeast sector. Peat is abundant and occurs in herbaceous and forested swamps that are individually up to 200 km2 in area. Northwest-directed littoral currents transport large volumes of suspended sediment and produce prominent mudcapes along the northwest coast. Mapping of surface sediments, vegetation, and major landforms identified four principal geomorphic systems within the western delta plain: (1) distributary channels, (2) interdistributary flood basins, (3) fluvial-marine transitional environments, and (4) marine-influenced coastal environments. Coring and radiocarbon dating of deltaic deposits show that the northern delta shoreline has prograded 20-30 km during the late Holocene sea-level highstand. Progradation has been accomplished by a combination of distributary avulsion and mudcape progradation. This style of deltaic progradation differs markedly from other deltas such as the Mississippi where distributary avulsion leads to coastal land loss, rather than shoreline progradation. The key difference is that the Orinoco Delta coastal zone receives prodigious amounts of sediment from northwest-moving littoral currents that transport

  13. A compilation of U.S. Geological Survey pesticide concentration data for water and sediment in the Sacramento–San Joaquin Delta region: 1990–2010

    Science.gov (United States)

    Orlando, James L.

    2013-01-01

    Beginning around 2000, abundance indices of four pelagic fishes (delta smelt, striped bass, longfin smelt, and threadfin shad) within the San Francisco Bay and Sacramento–San Joaquin Delta began to decline sharply (Sommer and others, 2007). These declines collectively became known as the pelagic organism decline (POD). No single cause has been linked to this decline, and current theories suggest that combinations of multiple stressors are likely to blame. Contaminants (including current-use pesticides) are one potential stressor being investigated for its role in the POD (Anderson, 2007). Pesticide concentration data collected by the U.S. Geological Survey (USGS) at multiple sites in the delta region over the past two decades are critical to understanding the potential effects of current-use pesticides on species of concern as well as the overall health of the delta ecosystem. In April 2010, a compilation of contaminant data for the delta region was published by the State Water Resources Control Board (Johnson and others, 2010). Pesticide occurrence was the major focus of this report, which concluded that “there was insufficient high quality data available to make conclusions about the potential role of specific contaminants in the POD.” The report cited multiple sources; however, data collected by the USGS were not included in the publication even though these data met all criteria listed for inclusion in the report. What follows is a summary of publicly available USGS data for pesticide concentrations in surface water and sediments within the Sacramento–San Joaquin Delta region from the years 1990 through 2010. Data were retrieved though the USGS National Water Information System (NWIS) database, a publicly available online-data repository (U.S. Geological Survey, 1998), and from published USGS reports (also available online at http://pubs.er.usgs.gov/). The majority of the data were collected in support of two long term USGS monitoring programs

  14. Primary production in the Delta: Then and now

    Science.gov (United States)

    Cloern, James E.; Robinson, April; Richey, Amy; Grenier, Letitia; Grossinger, Robin; Boyer, Katharyn E.; Burau, Jon; Canuel, Elizabeth A.; DeGeorge, John F.; Drexler, Judith Z.; Enright, Chris; Howe, Emily R.; Kneib, Ronald; Mueller-Solger, Anke; Naiman, Robert J.; Pinckney, James L.; Safran, Samuel M.; Schoellhamer, David H.; Simenstad, Charles A.

    2016-01-01

    To evaluate the role of restoration in the recovery of the Delta ecosystem, we need to have clear targets and performance measures that directly assess ecosystem function. Primary production is a crucial ecosystem process, which directly limits the quality and quantity of food available for secondary consumers such as invertebrates and fish. The Delta has a low rate of primary production, but it is unclear whether this was always the case. Recent analyses from the Historical Ecology Team and Delta Landscapes Project provide quantitative comparisons of the areal extent of 14 habitat types in the modern Delta versus the historical Delta (pre-1850). Here we describe an approach for using these metrics of land use change to: (1) produce the first quantitative estimates of how Delta primary production and the relative contributions from five different producer groups have been altered by large-scale drainage and conversion to agriculture; (2) convert these production estimates into a common currency so the contributions of each producer group reflect their food quality and efficiency of transfer to consumers; and (3) use simple models to discover how tidal exchange between marshes and open water influences primary production and its consumption. Application of this approach could inform Delta management in two ways. First, it would provide a quantitative estimate of how large-scale conversion to agriculture has altered the Delta's capacity to produce food for native biota. Second, it would provide restoration practitioners with a new approach—based on ecosystem function—to evaluate the success of restoration projects and gauge the trajectory of ecological recovery in the Delta region.

  15. Open-Source Electronic Health Record Systems for Low-Resource Settings: Systematic Review.

    Science.gov (United States)

    Syzdykova, Assel; Malta, André; Zolfo, Maria; Diro, Ermias; Oliveira, José Luis

    2017-11-13

    Despite the great impact of information and communication technologies on clinical practice and on the quality of health services, this trend has been almost exclusive to developed countries, whereas countries with poor resources suffer from many economic and social issues that have hindered the real benefits of electronic health (eHealth) tools. As a component of eHealth systems, electronic health records (EHRs) play a fundamental role in patient management and effective medical care services. Thus, the adoption of EHRs in regions with a lack of infrastructure, untrained staff, and ill-equipped health care providers is an important task. However, the main barrier to adopting EHR software in low- and middle-income countries is the cost of its purchase and maintenance, which highlights the open-source approach as a good solution for these underserved areas. The aim of this study was to conduct a systematic review of open-source EHR systems based on the requirements and limitations of low-resource settings. First, we reviewed existing literature on the comparison of available open-source solutions. In close collaboration with the University of Gondar Hospital, Ethiopia, we identified common limitations in poor resource environments and also the main requirements that EHRs should support. Then, we extensively evaluated the current open-source EHR solutions, discussing their strengths and weaknesses, and their appropriateness to fulfill a predefined set of features relevant for low-resource settings. The evaluation methodology allowed assessment of several key aspects of available solutions that are as follows: (1) integrated applications, (2) configurable reports, (3) custom reports, (4) custom forms, (5) interoperability, (6) coding systems, (7) authentication methods, (8) patient portal, (9) access control model, (10) cryptographic features, (11) flexible data model, (12) offline support, (13) native client, (14) Web client,(15) other clients, (16) code

  16. Surface structure of Bi2Sr2CaCu2O(8+delta) high-temperature superconductors studied using low-energy electron diffraction

    Science.gov (United States)

    Lindberg, P. A. P.; Shen, Z.-X.; Wells, B. O.; Mitzi, D. B.; Lindau, I.

    1988-12-01

    The surface structure of Bi2Sr2CaCu2O(8+delta) has been studied using low-energy electron diffraction (LEED). Sharp diffraction spots indicative of a well-ordered surface are observed. The LEED patterns unequivocally show that this type of material preferentially cleaves along the a-b planes of the nearly tetragonal unit cell. A superstructure extending along one of the axes in the a-b plane (b) is found to have a periodicity of 27 + or - 0.5 A, in good agreement with earlier studies of the three-dimensional crystal structure. The superstructure at the surface is nonlocal in character and reflects the long-range superlattice of the bulk along the b axis. Intensity modulations of the diffraction spots oriented along the b axis are also reported and discussed in terms of the cell dimension of the unit cell along the b axis.

  17. Surface-conduction electron-emitter characteristics and fabrication based on vertically aligned carbon nanotube arrays

    Energy Technology Data Exchange (ETDEWEB)

    Shih, Yi-Ting [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Li, Kuan-Wei [Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Honda, Shin-ichi [Graduate School of Engineering, University of Hyogo, 2167 Shosha, Himeji, Hyogo 671-2280 (Japan); Lin, Pao-Hung; Huang, Ying-Sheng [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Lee, Kuei-Yi, E-mail: kylee@mail.ntust.edu.tw [Graduate Institute of Electro-Optical Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China); Department of Electronic and Computer Engineering, National Taiwan University of Science and Technology, No. 43, Section 4, Keelung Road, Taipei 10607, Taiwan (China)

    2017-06-01

    Graphical abstract: The pattern design provides a new structure of surface-conduction electron-emitter display (SED). Delta-star shaped vertically aligned CNT (VACNT) arrays with 20o tips can simultaneously provide three emitters to bombard the sides of equilateral triangles pattern of VACNT, which produces numerous secondary electrons and enhance the SED efficiency. - Highlights: • The carbon nanotube (CNT) has replaced palladium oxide (PdO) as the electrode material for surface-conduction electron-emitter (SCE) applications. • The vertically aligned CNT (VACNT) arrays with 20° tips of the delta-star arrangement are used as cathodes that easily emit electrons. The cathode pattern simultaneously provides three emitters to bombard the sides of equilateral triangles pattern of VACNT. • The VACNT arrays were covered with magnesium oxide (MgO) nanostructures to promote the surface-conduction electron-emitter display (SED) efficiency (η). • The η was stably maintained in the 75–85% range. The proposed design provides a facile new method for developing SED applications. - Abstract: The carbon nanotube (CNT) has replaced palladium oxide (PdO) as the electrode material for surface-conduction electron-emitter (SCE) applications. Vertically aligned CNT arrays with a delta-star arrangement were patterned and synthesized onto a quartz substrate using photolithography and thermal chemical vapor deposition. Delta-star shaped VACNT arrays with 20° tips are used as cathodes that easily emit electrons because of their high electrical field gradient. In order to improve the field emission and secondary electrons (SEs) in SCE applications, magnesium oxide (MgO) nanostructures were coated onto the VACNT arrays to promote the surface-conduction electron-emitter display (SED) efficiency (η). According to the definition of η in SCE applications, in this study, the η was stably maintained in the 75–85% range. The proposed design provides a facile new method for

  18. Environmental challenges in Nigeria's Delta Region and Agriculture ...

    African Journals Online (AJOL)

    The paper discussed the environmental challenges in the Niger-Delta region of Nigeria with emphasis on the impacts on agricultural production. It thus discussed the concepts of Niger-Delta, Environmental pollution, Niger-Delta crises and Agriculture. The paper posits that there are positive relationships between these ...

  19. Losses of Sacramento River Chinook Salmon and Delta Smelt to Entrainment in Water Diversions in the Sacramento–San Joaquin Delta

    Directory of Open Access Journals (Sweden)

    Wim J. Kimmerer

    2008-06-01

    Full Text Available Pumping at the water export facilities in the southern Sacramento-San Joaquin Delta kills fish at and near the associated fish-salvage facilities. Correlative analyses of salvage counts with population indices have failed to provide quantitative estimates of the magnitude of this mortality. I estimated the proportional losses of Sacramento River Chinook salmon (Oncorhynchus tshawytscha and delta smelt (Hypomesus transpacificus to place these losses in a population context. The estimate for salmon was based on recoveries of tagged smolts released in the upper Sacramento River basin, and recovered at the fish-salvage facilities in the south Delta and in a trawling program in the western Delta. The proportion of fish salvaged increased with export flow, with a mean value around 10% at the highest export flows recorded. Mortality was around 10% if pre-salvage losses were about 80%, but this value is nearly unconstrained. Losses of adult delta smelt in winter and young delta smelt in spring were estimated from salvage data (adults corrected for estimated pre-salvage survival, or from trawl data in the southern Delta (young. These losses were divided by population size and accumulated over the respective seasons. Losses of adult delta smelt were 1–50% (median 15% although the highest value may have been biased upward. Daily losses of larvae and juveniles were 0–8%, and seasonal losses accumulated were 0–25% (median 13%. The effect of these losses on population abundance was obscured by subsequent 50-fold variability in survival from summer to fall.

  20. Electronic Structure of Low-Dimensional Carbon Π-Systems

    DEFF Research Database (Denmark)

    García Lastra, Juan Maria; Boukahil, Idris; Qiao, Ruimin

    2016-01-01

    , and the electron hole interaction. For the latter, we develop a simple model that accurately represents a full Delta-self-consistent field (ΔSCF) calculation. The distortion of the LUMO because of its interaction with the C is hole is investigated. These results illustrate the electronic states of prototypical Π...

  1. The political economy of oil and the Niger Delta crisis

    Science.gov (United States)

    Ighodaro, Osaro O.

    This study is about the burgeoning crisis in Nigeria's Oil Producing Niger Delta region. Discerning the intersecting contributive factors to the crisis, this dissertation suggests that the Niger Delta crisis is symptomatic of challenges to development in Nigeria. Due to the insidious colonial/neo-colonial practices of subjugation, and exploitation of the host communities, it is suggested that the extractive, super-profit motive of Shell, the concomitant environmental degradation, corruption of a bellicose state, ethnic conflict and suffering of the masses are outcomes of a long historically debilitating relationship with international capital which causes irreparable retardation to the host communities. From cash crop economy to a mono-oil economy resources are removed from the communities and used to enhance the colonial state and their post-colonial harbingers of misery. Hence, the indigenous people claim that the Niger Delta is in a crisis, and they are willing to confront the triple alliance of multinational oil companies like Shell, the Nigerian State and the local elite so long as these allies of subjugation continue to neglect the goose that lays the proverbial golden egg (oil that is). Theoretically, a hybrid Political Economy approach was adopted as the over-aching framework for the study, while Dependency theory, modified by what I have called African Transformative scholarly perspective, served as the conceptual tool. Primary and secondary sources of data, including personal observation, interviews, official government documents and other publications were utilized for this analysis. In view of recommendations, it is suggested that first, the Nigerian state should assume decisive and unflinching leadership in holding oil companies responsible for their activities in the host communities; second, oil companies (like Shell) should see themselves as an integral part of the host communities; invest in their development by providing employment opportunities

  2. Displacement waves in La2CuO(4-delta) and La(1.85)Sr(0.15)CuO(4-delta)

    Science.gov (United States)

    Kajitani, Tsuyoshi; Onozuka, Takashi; Yamaguchi, Yasuo; Hirabayashi, Makoto; Syono, Yasuhiko

    1987-11-01

    Structural investigation of orthorhombic La2CuO(4-delta) and La(1.85)Sr(0.15)CuO(4-delta) was carried out by means of X-ray and neutron diffraction on the basis of the space group Cmmm. The periodic expansion/contraction type distortion of CuO6 octahedra was found in both orthorhombic compounds. The distortion is nearly one-dimensional in La2CuO(4-delta) but is two-dimensional in La(1.85)Sr(0.15)CuO(4-delta). The existence of a charge-density wave is highly possible in the structures.

  3. First-principles elastic constants and phonons of delta-Pu

    DEFF Research Database (Denmark)

    Söderlind, P.; Landa, A.; Sadigh, B.

    2004-01-01

    Elastic constants and zone-boundary phonons of delta-plutonium have been calculated within the density-functional theory. The paramagnetic state of delta-Pu is modeled by disordered magnetism utilizing either the disordered local moment or the special quasirandom structure techniques. The anomalo......Elastic constants and zone-boundary phonons of delta-plutonium have been calculated within the density-functional theory. The paramagnetic state of delta-Pu is modeled by disordered magnetism utilizing either the disordered local moment or the special quasirandom structure techniques....... The anomalously soft C-' as well as a large anisotropy ratio (C-44/C-') of delta-Pu is reproduced by this theoretical model. Also the recently measured phonons for delta-Pu compare relatively well with their theoretical counterpart at the zone boundaries....

  4. Addressing Breast Cancer Health Disparities in the Mississippi Delta Through an Innovative Partnership for Education, Detection, and Screening.

    Science.gov (United States)

    Mayfield-Johnson, Susan; Fastring, Danielle; Fortune, Melody; White-Johnson, Freddie

    2016-06-01

    Projects to reduce disparities in cancer treatment and research include collaborative partnerships and multiple strategies to promote community awareness, education, and engagement. This is especially needed in underserved areas such as the Mississippi Delta where more women are diagnosed at regional and distant stages of breast cancer. The purpose for this project was to increase the relatively low screening rate for African American women in the Mississippi Delta through a partnership between the Mississippi Network for Cancer Control and Prevention at The University of Southern Mississippi, The Fannie Lou Hamer Cancer Foundation and the Mississippi State Department of Health to decrease health disparities in breast cancer through increased awareness on self-early detection methods, leveraging resources to provide mammography screenings, and adequate follow-up with services and treatment for abnormal findings. Through this collaborative effort, over 500 women in three rural Mississippi Delta counties were identified, provided community education on early self-detection, and given appointments for mammography screenings within one fiscal year.

  5. Stimulation of accumbal GABAA receptors inhibits delta2-, but not delta1-, opioid receptor-mediated dopamine efflux in the nucleus accumbens of freely moving rats.

    Science.gov (United States)

    Aono, Yuri; Kiguchi, Yuri; Watanabe, Yuriko; Waddington, John L; Saigusa, Tadashi

    2017-11-15

    The nucleus accumbens contains delta-opioid receptors that may reduce inhibitory neurotransmission. Reduction in GABA A receptor-mediated inhibition of accumbal dopamine release due to delta-opioid receptor activation should be suppressed by stimulating accumbal GABA A receptors. As delta-opioid receptors are divided into delta2- and delta1-opioid receptors, we analysed the effects of the GABA A receptor agonist muscimol on delta2- and delta1-opioid receptor-mediated accumbal dopamine efflux in freely moving rats using in vivo microdialysis. Drugs were administered intracerebrally through the dialysis probe. Doses of compounds indicate total amount administered (mol) during 25-50min infusions. The delta2-opioid receptor agonist deltorphin II (25.0nmol)- and delta1-opioid receptor agonist DPDPE (5.0nmol)-induced increases in dopamine efflux were inhibited by the delta2-opioid receptor antagonist naltriben (1.5nmol) and the delta1-opioid receptor antagonist BNTX (150.0pmol), respectively. Muscimol (250.0pmol) inhibited deltorphin II (25.0nmol)-induced dopamine efflux. The GABA A receptor antagonist bicuculline (50.0pmol), which failed to affect deltorphin II (25.0nmol)-induced dopamine efflux, counteracted the inhibitory effect of muscimol on deltorphin II-induced dopamine efflux. Neither muscimol (250.0pmol) nor bicuculline (50.0 and 500.0pmol) altered DPDPE (5.0nmol)-induced dopamine efflux. The present results show that reduction in accumbal GABA A receptor-mediated inhibition of dopaminergic activity is necessary to produce delta2-opioid receptor-induced increase in accumbal dopamine efflux. This study indicates that activation of delta2- but not delta1-opioid receptors on the cell bodies and/or terminals of accumbal GABAergic interneurons inhibits GABA release and, accordingly, decreases GABA A receptor-mediated inhibition of dopaminergic terminals, resulting in enhanced accumbal dopamine efflux. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Evaluation of three electronic report processing systems for preparing hydrologic reports of the U.S Geological Survey, Water Resources Division

    Science.gov (United States)

    Stiltner, G.J.

    1990-01-01

    In 1987, the Water Resources Division of the U.S. Geological Survey undertook three pilot projects to evaluate electronic report processing systems as a means to improve the quality and timeliness of reports pertaining to water resources investigations. The three projects selected for study included the use of the following configuration of software and hardware: Ventura Publisher software on an IBM model AT personal computer, PageMaker software on a Macintosh computer, and FrameMaker software on a Sun Microsystems workstation. The following assessment criteria were to be addressed in the pilot studies: The combined use of text, tables, and graphics; analysis of time; ease of learning; compatibility with the existing minicomputer system; and technical limitations. It was considered essential that the camera-ready copy produced be in a format suitable for publication. Visual improvement alone was not a consideration. This report consolidates and summarizes the findings of the electronic report processing pilot projects. Text and table files originating on the existing minicomputer system were successfully transformed to the electronic report processing systems in American Standard Code for Information Interchange (ASCII) format. Graphics prepared using a proprietary graphics software package were transferred to all the electronic report processing software through the use of Computer Graphic Metafiles. Graphics from other sources were entered into the systems by scanning paper images. Comparative analysis of time needed to process text and tables by the electronic report processing systems and by conventional methods indicated that, although more time is invested in creating the original page composition for an electronically processed report , substantial time is saved in producing subsequent reports because the format can be stored and re-used by electronic means as a template. Because of the more compact page layouts, costs of printing the reports were 15% to 25

  7. Tidal modulated flow and sediment flux through Wax Lake Delta distributary channels: Implications for delta development

    Directory of Open Access Journals (Sweden)

    K. Hanegan

    2015-03-01

    Full Text Available In this study, a Delft3D model of the Wax Lake Delta was developed to simulate flow and sediment flux through delta distributary channels. The model was calibrated for tidal constituents as well as velocity and sediment concentration across channel transects. The calibrated model was then used to simulate full spring–neap tidal cycles under constant low flow upstream boundary conditions, with grain size variation in suspended load represented using two sediment fractions. Flow and sediment flux results through distributary channel cross-sections were examined for spatial and temporal variability with the goal of characterizing the role of tides in sediment reworking and delta development. The Wax Lake Delta has prograded through channel extension, river mouth bar deposition, and channel bifurcation. Here we show that tidal modulation of currents influences suspended sand transport, and spatial acceleration through distributary channels at low tides is sufficient to suspend sand in distal reaches during lower flows. The basinward-increasing transport capacity in distributary channels indicates that erosive channel extension could be an important process, even during non-flood events.

  8. Primary Production in the Delta: Then and Now

    Directory of Open Access Journals (Sweden)

    James E. Cloern

    2016-10-01

    Full Text Available doi: http://dx.doi.org/10.15447/sfews.2016v14iss3art1To evaluate the role of restoration in the recovery of the Delta ecosystem, we need to have clear targets and performance measures that directly assess ecosystem function. Primary production is a crucial ecosystem process, which directly limits the quality and quantity of food available for secondary consumers such as invertebrates and fish. The Delta has a low rate of primary production, but it is unclear whether this was always the case. Recent analyses from the Historical Ecology Team and Delta Landscapes Project provide quantitative comparisons of the areal extent of 14 habitat types in the modern Delta versus the historical Delta (pre-1850. Here we describe an approach for using these metrics of land use change to: (1 produce the first quantitative estimates of how Delta primary production and the relative contributions from five different producer groups have been altered by large-scale drainage and conversion to agriculture; (2 convert these production estimates into a common currency so the contributions of each producer group reflect their food quality and efficiency of transfer to consumers; and (3 use simple models to discover how tidal exchange between marshes and open water influences primary production and its consumption. Application of this approach could inform Delta management in two ways. First, it would provide a quantitative estimate of how large-scale conversion to agriculture has altered the Delta's capacity to produce food for native biota. Second, it would provide restoration practitioners with a new approach—based on ecosystem function—to evaluate the success of restoration projects and gauge the trajectory of ecological recovery in the Delta region.

  9. Bias dependent charge trapping in MOSFETs during 1 and 6 MeV electron irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shinde, N.S. [Department of Chemical Engineering, Mie University, 5148507 (Japan); Kulkarni, V.R.; Mathakari, N.L.; Bhoraskar, V.N. [Department of Physics, Univeristy of Pune, Pune 411007 (India); Dhole, S.D. [Department of Physics, Univeristy of Pune, Pune 411007 (India)], E-mail: sanjay@physics.unipune.ernet.in

    2008-06-15

    To study irradiation-induced charge trapping in SiO{sub 2} and around the SiO{sub 2}-Si interface, depletion n-MOSFETs (metal-oxide-semiconductor field effect transistor) were used. The devices were gate biased during 1 and 6 MeV pulsed electron irradiation. The I{sub D}-V{sub DS} (drain current versus drain voltage) and I{sub D}-V{sub GS} (drain current versus gate voltage) characteristics were measured before and after irradiation. The shift in threshold voltage {delta}V{sub T} (difference in threshold voltage V{sub T} before and after irradiation) exhibited trends depending on the applied gate bias during 1 MeV electron irradiation. This behavior can be associated to the contribution of irradiation-induced negative charge {delta}N{sub IT} buildup around the SiO{sub 2}-Si interface to {delta}V{sub T}, which is sensitive to the electron tunneling from the substrates. However, only weak gate bias dependence was observed in 6 MeV electron irradiated devices. Independent of the energy loss and applied bias, the positive oxide trapped charge {delta}N{sub OT} is marginal and can be associated to thin and good quality of SiO{sub 2}. These results are explained using screening of free and acceptor states by the applied bias during irradiation, thereby reducing the total irradiation-induced charges.

  10. Use and User Perception of Electronic Information Resources: A Case Study of Siva Institute of Frontier Technology, India

    Directory of Open Access Journals (Sweden)

    Velmurugan Chandran

    2013-12-01

    Full Text Available The present study aims to explore the use and user perception of electronic resources in Siva Institute of Frontier Technology, India. A total number of 123 users were taken into account for the study through a questionnaire-based survey method. A well-structured questionnaire was designed and distributed to the selected 200 students and staff members. 123 copies of the questionnaires were returned dully filled in and the overall response rate was 61.50 percent. The questionnaire contained both open- and close-ended questions. The collected data were classified, analyzed, and tabulated by using simple statistical methods. This study covers the impact of electronic resources on students and faculty in their academic pursuit.

  11. A preliminary categorization of end-of-life electrical and electronic equipment as secondary metal resources

    International Nuclear Information System (INIS)

    Oguchi, Masahiro; Murakami, Shinsuke; Sakanakura, Hirofumi; Kida, Akiko; Kameya, Takashi

    2011-01-01

    Highlights: → End-of-life electrical and electronic equipment (EEE) as secondary metal resources. → The content and the total amount of metals in specific equipment are both important. → We categorized 21 EEE types from contents and total amounts of various metals. → Important equipment types as secondary resources were listed for each metal kind. → Collectability and possible collection systems of various EEE types were discussed. - Abstract: End-of-life electrical and electronic equipment (EEE) has recently received attention as a secondary source of metals. This study examined characteristics of end-of-life EEE as secondary metal resources to consider efficient collection and metal recovery systems according to the specific metals and types of EEE. We constructed an analogy between natural resource development and metal recovery from end-of-life EEE and found that metal content and total annual amount of metal contained in each type of end-of-life EEE should be considered in secondary resource development, as well as the collectability of the end-of-life products. We then categorized 21 EEE types into five groups and discussed their potential as secondary metal resources. Refrigerators, washing machines, air conditioners, and CRT TVs were evaluated as the most important sources of common metals, and personal computers, mobile phones, and video games were evaluated as the most important sources of precious metals. Several types of small digital equipment were also identified as important sources of precious metals; however, mid-size information and communication technology (ICT) equipment (e.g., printers and fax machines) and audio/video equipment were shown to be more important as a source of a variety of less common metals. The physical collectability of each type of EEE was roughly characterized by unit size and number of end-of-life products generated annually. Current collection systems in Japan were examined and potentially appropriate collection

  12. Principles of formation of the content of an educational electronic resource on the basis of general and didactic patterns of learning

    Directory of Open Access Journals (Sweden)

    Ольга Юрьевна Заславская

    2018-12-01

    Full Text Available The article considers the influence of the development of technical means of teaching on the effectiveness of educational and methodical resources. Modern opportunities of information and communication technologies allow creating electronic educational resources that represent educational information that automates the learning process, provide information assistance, if necessary, collect and process statistical information on the degree of development of the content of the school material by schoolchildren, set an individual trajectory of learning, and so on. The main principle of data organization is the division of the training course into separate sections on the thematic elements and components of the learning process. General regularities include laws that encompass the entire didactic system, and in specific (particular cases, those whose actions extend to a separate component (aspect of the system. From the standpoint of the existence of three types of electronic training modules in the aggregate content of the electronic learning resource - information, control and module of practical classes - the principles of the formation of the electronic learning resource, in our opinion, should regulate all these components. Each of the certain principles is considered in the groups: scientific orientation, methodological orientation, systemic nature, accounting of interdisciplinary connections, fundamentalization, systematic and dosage sequence, rational use of study time, accessibility, minimization, operationalization of goals, unified identification diagnosis.

  13. The influence of delta formation mechanism on geotechnical property sequence of the late Pleistocene–Holocene sediments in the Mekong River Delta

    Directory of Open Access Journals (Sweden)

    Truong Minh Hoang

    2016-11-01

    Full Text Available The aim of the study was to characterize a variety of microstructure development-levels and geotechnical property sequences of the late Pleistocene–Holocene deposits in the Mekong River delta (MRD, and the paper furthermore discusses the influences of delta formation mechanisms on them. The survey associated the geotechnical engineering and the sedimentary geology of the late Pleistocene–Holocene deposits at five sites and also undifferentiated Pleistocene sediments. A cross-section which was rebuilt in the delta progradation-direction and between the Mekong and Bassac rivers represents the stratigraphy. Each sedimentary unit was formed under a different delta formation mechanism and revealed a typical geotechnical property sequence. The mechanical behaviors of the sediment succession in the tide-dominated delta with significant fluvial-activity and material source tend to be more cohesionless soils and strengths than those in the tide- and wave-dominated delta and even the coast. The particular tendency of the mechanical behavior of the deposit succession can be reasonably estimated from the delta formation mechanism. The characteristics of the clay minerals from the Mekong River produced the argillaceous soil which does not have extremely high plasticity. The microstructure development-levels are low to very high indicating how to choose hydraulic conductivity value, k, for estimating overconsolidation ratio, OCR, by the piezocone penetration tests (CPTU. The OCR of sediments in the delta types strangely change with depth but none less than 1. The post-depositional processes significantly influenced the microstructure development, particularly the dehydrating and oxidizing processes.

  14. Construction area expansion in relation to economic-demographic development and land resource in the Pearl River Delta of China

    NARCIS (Netherlands)

    Liu, Zhijia; Huang, Heqing; Werners, Saskia E.; Yan, Dan

    2016-01-01

    Since 1979, the Pearl River Delta (PRD) of China has experienced rapid socioeconomic development along with a fast expansion of construction area. Affected by both natural and human factors, a complex interdependency is found among the regional changes in construction area, GDP and population. A

  15. An integrated framework to assess plausible future livelihood and poverty changes in deltas: an application to coastal Bangladesh

    Science.gov (United States)

    Lázár, A. N.; Payo, A.; Nicholls, R. J.; Hutton, C.; Adams, H.; Salehin, M.; Haque, A.; Clarke, D.; Bricheno, L.; Fernandes, J. A.; Rahman, M.; Ahmed, A.; Streatfield, P. K.

    2015-12-01

    Deltas represent one of the most densely populated areas in the world. This is especially true for the coastal zone of Bangladesh where more than a thousand people live in each square kilometre of land. Livelihoods, food security and poverty in Bangladesh are strongly dependent on natural resources affected by several factors including climate variability and change, upstream river flow modifications, commercial fish catches in the Bay of Bengal, and engineering interventions such as polderisation. The scarcity of fresh water, saline water intrusion and natural disasters (e.g. river flooding, cyclones and storm surges) have negative impact on drinking water availability and crop irrigation potential; thus severely affect land use and livelihood opportunities of the coastal population. Hydro-environmental changes can be especially detrimental for the well-being of the poorest households that are highly dependent on natural resources. The ESPA Deltas project aims to holistically examine the interaction between the coupled bio-physical environment and the livelihoods of these poor populations in coastal Bangladesh. Here we describe a new integrated model that allows the long-term analysis of the possible changes in this system by linking projected changes in physical processes (e.g. river flows, nutrients), with productivity (e.g. fish, rice), social processes (e.g. access, property rights, migration) and governance/management (e.g. fisheries, agriculture, water and land use management). This integrated approach is designed to provide Bangladeshi policy makers with science-based evidence of possible development trajectories within the coastal delta plain over timescales up to 50 years, including the likely robustness of different governance options on natural resource conservation and poverty levels. This presentation describes the model framework and aims to illustrate the cause-effect relationship in-between changes of the hydro-environment and the livelihoods and

  16. Displacement waves in La/sub 2/CuO(4-delta) and La(1. 85)Sr(0. 15)CuO(4-delta)

    Energy Technology Data Exchange (ETDEWEB)

    Kajitani, T.; Onozuka, T.; Yamaguchi, Y.; Hirabayashi, M.; Syono, Y.

    1987-11-01

    Structural investigation of orthorhombic La/sub 2/CuO(4-delta) and La(1.85)Sr(0.15)CuO(4-delta) was carried out by means of X-ray and neutron diffraction on the basis of the space group Cmmm. The periodic expansion/contraction type distortion of CuO6 octahedra was found in both orthorhombic compounds. The distortion is nearly one-dimensional in La/sub 2/CuO(4-delta) but is two-dimensional in La(1.85)Sr(0.15)CuO(4-delta). The existence of a charge-density wave is highly possible in the structures. 20 references.

  17. Nonlinear delta f Simulations of Collective Effects in Intense Charged Particle Beams

    CERN Document Server

    Hong Qi

    2003-01-01

    A nonlinear delta(f) particle simulation method based on the Vlasov-Maxwell equations has been recently developed to study collective processes in high-intensity beams, where space-charge and magnetic self-field effects play a critical role in determining the nonlinear beam dynamics. Implemented in the Beam Equilibrium, Stability and Transport (BEST) code [H. Qin, R.C. Davidson, and W.W. Lee, Physical Review -- Special Topics on Accelerator and Beams 3 (2000) 084401; 3 (2000) 109901.], the nonlinear delta(f) method provides a low-noise and self-consistent tool for simulating collective interactions and nonlinear dynamics of high-intensity beams in modern and next-generation accelerators and storage rings, such as the Spallation Neutron Source and heavy ion fusion drivers. A wide range of linear eigenmodes of high-intensity charged-particle beams can be systematically studied using the BEST code. Simulation results for the electron-proton two-stream instability in the Proton Storage Ring experiment [R. Macek, ...

  18. How yield relates to ash content, Delta 13C and Delta 18O in maize grown under different water regimes.

    Science.gov (United States)

    Cabrera-Bosquet, Llorenç; Sánchez, Ciro; Araus, José Luis

    2009-11-01

    Stable isotopes have proved a valuable phenotyping tool when breeding for yield potential and drought adaptation; however, the cost and technical skills involved in isotope analysis limit its large-scale application in breeding programmes. This is particularly so for Delta(18)O despite the potential relevance of this trait in C(4) crops. The accumulation of minerals (measured as ash content) has been proposed as an inexpensive way to evaluate drought adaptation and yield in C(3) cereals, but little is known of the usefulness of this measure in C(4) cereals such as maize (Zea mays). The present study investigates how yield relates to ash content, Delta(13)C and Delta(18)O, and evaluates the use of ash content as an alternative or complementary criterion to stable isotopes in assessing yield potential and drought resistance in maize. A set of tropical maize hybrids developed by CIMMYT were subjected to different water availabilities, in order to induce water stress during the reproductive stages under field conditions. Ash content and Delta(13)C were determined in leaves and kernels. In addition, Delta(18)O was measured in kernels. Water regime significantly affected yield, ash content and stable isotopes. The results revealed a close relationship between ash content in leaves and the traits informing about plant water status. Ash content in kernels appeared to reflect differences in sink-source balance. Genotypic variation in grain yield was mainly explained by the combination of ash content and Delta(18)O, whilst Delta(13)C did not explain a significant percentage of such variation. Ash content in leaves and kernels proved a useful alternative or complementary criterion to Delta(18)O in kernels for assessing yield performance in maize grown under drought conditions.

  19. From Millennium ERM to Proquest 360 Resource Manager: Implementing a new Electronic Resources Management System ERMS in an International Graduate Research University in Saudi Arabia

    KAUST Repository

    Ramli, Rindra M.

    2017-05-17

    An overview of the Recommendation Study and the subsequent Implementation of a new Electronic Resources Management system ERMS in an international graduate research university in the Kingdom of Saudi Arabia. It covers the timeline, deliverables and challenges as well as lessons learnt by the Project Team.

  20. Hydrological and Climatic Significance of Martian Deltas

    Science.gov (United States)

    Di Achille, G.; Vaz, D. A.

    2017-10-01

    We a) review the geomorphology, sedimentology, and mineralogy of the martian deltas record and b) present the results of a quantitative study of the hydrology and sedimentology of martian deltas using modified version of terrestrial model Sedflux.

  1. Abraham Reef Stable Isotope Data (delta 13C, delta 18O, delta 14C) for 1635-1957

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Site: Abraham Reef, 22ó 06'S, 153ó 00'E, Porites australiensus, Radiocarbon (delta 14C) and Stable Isotope (del 18O and del 13C) results from bi-annual samples from...

  2. Delta Plaza kohvik = The Delta Plaza Café / Margit Mutso

    Index Scriptorium Estoniae

    Mutso, Margit, 1966-

    2010-01-01

    Tallinnas Pärnu mnt. 141 asuva kohviku Delta Plaza sisekujundusest. Sisearhitektid Tiiu Truus ja Marja Viltrop (Stuudio Truus OÜ). Hoone arhitektid Jüri Okas ja Marika Lõoke (AB J. Okas & M. Lõoke). Žürii liikme Mait Summataveti arvamus kohvikust

  3. Studying medium effects with the optimized {delta} expansion

    Energy Technology Data Exchange (ETDEWEB)

    Krein, G [Instituto de Fisica Teorica (IFT), Sao Paulo, SP (Brazil); Menezes, D P [Santa Catarina Univ., Florianopolis, SC (Brazil). Dept. de Fisica; Nielsen, M [Sao Paulo Univ., SP (Brazil). Inst. de Fisica; Pinto, M B [Montpellier-2 Univ., 34 (France). Lab. de Physique Mathematique

    1995-04-01

    The possibility of using the optimized {delta} expansion for studying medium effects on hadronic properties in quark or nuclear matter is investigated. The {delta} expansion is employed to study density effects with two commonly used models in hadron and nuclear physics, the Nambu-Jona-Lasinio model for the dynamical chiral symmetry breaking and the Walecka model for the equation of state of nuclear matter. The results obtained with the {delta} expansion are compared to those obtained with the traditional Hartree-Fock approximation. Perspectives for using the {delta} expansion in other field theoretic models in hadron and nuclear physics are discussed. (author). 17 refs, 9 figs.

  4. The Synthesis of the Hierarchical Structure of Information Resources for Management of Electronic Commerce Entities

    Directory of Open Access Journals (Sweden)

    Krutova Anzhelika S.

    2017-06-01

    Full Text Available The aim of the article is to develop the theoretical bases for the classification and coding of economic information and the scientific justification of the content of information resources of an electronic commerce enterprise. The essence of information resources for management of electronic business entities is investigated. It is proved that the organization of accounting in e-commerce systems is advisable to be built on the basis of two circuits: accounting for financial flows and accounting associated with transformation of business factors in products and services as a result of production activities. There presented a sequence of accounting organization that allows to combine the both circuits in a single information system, which provides a possibility for the integrated replenishment and distributed simultaneous use of the e-commerce system by all groups of users. It is proved that the guarantee of efficient activity of the information management system of electronic commerce entities is a proper systematization of the aggregate of information resources on economic facts and operations of an enterprise in accordance with the management tasks by building the hierarchy of accounting nomenclatures. It is suggested to understand nomenclature as an objective, primary information aggregate concerning a certain fact of the economic activity of an enterprise, which is characterized by minimum requisites, is entered into the database of the information system and is to be reflected in the accounting system. It is proposed to build a database of e-commerce systems as a part of directories (constants, personnel, goods / products, suppliers, buyers and the hierarchy of accounting nomenclatures. The package of documents regulating the organization of accounting at an enterprise should include: the provision on the accounting services, the order on the accounting policy, the job descriptions, the schedules of information exchange, the report card and

  5. Non-self-sustained electric discharge in oxygen gas mixtures: singlet delta oxygen production

    CERN Document Server

    Ionin, A A; Kotkov, A A; Kochetov, I V; Napartovich, A P; Seleznev, L V; Sinitsyn, D V; Hager, G D

    2003-01-01

    The possibility of obtaining a high specific input energy in an electron-beam sustained discharge ignited in oxygen gas mixtures O sub 2 : Ar : CO (or H sub 2) at the total gas pressures of 10-100 Torr was experimentally demonstrated. The specific input energy per molecular component exceeded approx 6 kJ l sup - sup 1 atm sup - sup 1 (150 kJ mol sup - sup 1) as a small amount of carbon monoxide was added into a gas mixture of oxygen and argon. It was theoretically demonstrated that one might expect to obtain a singlet delta oxygen yield of 25% exceeding its threshold value needed for an oxygen-iodine laser operation at room temperature, when maintaining a non-self-sustained discharge in oxygen gas mixtures with molecular additives CO, H sub 2 or D sub 2. The efficiency of singlet delta oxygen production can be as high as 40%.

  6. Antinociceptive activity of Delta9-tetrahydrocannabinol non-ionic microemulsions.

    Science.gov (United States)

    Lazzari, P; Fadda, P; Marchese, G; Casu, G L; Pani, L

    2010-06-30

    Delta(9)-Tetrahydrocannabinol (Delta(9)-THC), the major psychoactive constituent of Cannabis sativa L., has been widely studied for its potential pharmaceutical application in the treatment of various diseases and disturbs. This sparingly soluble terpeno-phenolic compound is not easy to handle and to be formulated in pharmaceutical preparations. The aim of this work was to develop a stable aqueous Delta(9)-THC formulation acceptable for different ways of administration, and to evaluate the therapeutic properties of the new Delta(9)-THC based preparation for pain treatment. Due to the thermodynamic stability and advantages of microemulsion based systems, the study was focused on the identification of aqueous microemulsion based systems containing Delta(9)-THC. Oil in water Delta(9)-THC microemulsions were individuated through phase diagrams construction, using the non-ionic surfactant Solutol HS15, being this surfactant acceptable for parenteral administration in human. A selected microemulsion samples containing 0.2 wt% of Delta(9)-THC, stable up to 52 degrees C, was successfully assayed on animal models of pain. Significant antinociceptive activity has been detected by both intraperitoneal and intragastric administration of the new Delta(9)-THC pharmaceutical preparation. The effect has been highlighted in shorter time if compared to a preparation of the same active principle based on previously reported conventional preparation. 2010 Elsevier B.V. All rights reserved.

  7. LIVER TRANSPLANTATION IN HEPATITIS DELTA: SOUTH AMERICA EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Daniel Souza LIMA

    Full Text Available ABSTRACT BACKGROUND: The Amazon region is one of the main endemic areas of hepatitis delta in the world and the only one related to the presence of genotype 3 of the delta virus. OBJECTIVE: To analyze the profile, mortality and survival of cirrhotic patients submitted to liver transplantation for chronic hepatitis delta virus and compare with those transplanted by hepatitis B virus monoinfection. METHODS: Retrospective, observational and descriptive study. From May 2002 to December 2011, 629 liver transplants were performed at the Walter Cantídio University Hospital, of which 29 patients were transplanted due to cirrhosis caused by chronic delta virus infection and 40 by hepatitis B chronic monoinfection. The variables analyzed were: age, sex, MELD score, Child-Pugh score, upper gastrointestinal bleeding and hepatocellular carcinoma occurrence before the transplantation, perioperative platelet count, mortality and survival. RESULTS: The Delta Group was younger and all came from the Brazilian Amazon Region. Group B presented a higher proportion of male patients (92.5% compared to Group D (58.6%. The occurrence of upper gastrointestinal bleeding before transplantation, MELD score, and Child-Pugh score did not show statistical differences between groups. The occurrence of hepatocellular carcinoma and mortality were higher in the hepatitis B Group. The survival in 4 years was 95% in the Delta Group and 75% in the B Group, with a statistically significant difference (P=0.034. Patients with hepatitis delta presented more evident thrombocytopenia in the pre-transplantation and in the immediate postoperative period. CONCLUSION: The hepatitis by delta virus patients who underwent liver transplantation were predominantly male, coming from the Brazilian Amazon region and with similar liver function to the hepatitis B virus patients. They had a lower incidence of hepatocellular carcinoma, more marked perioperative thrombocytopenia levels and frequent

  8. Experiences with delta compression of data produced by DIII

    International Nuclear Information System (INIS)

    Henline, P.A.

    1986-01-01

    The amount of data collected for each tokamak experimental shot is rapidly increasing. This is caused by many factors, including more diagnostic experiments, reduced cost of electronics hardware (especially memory), and longer plasma duration. The design goal for the DIII-D tokamak is 25 Mbytes of data per shot. In order to store the shot data as one logical unit, the delta compression algorithm, as it was implemented at ORNL by E. Blair, is being used. Statistics on compression factors, times, and general usage will be presented for actual DIII data. Data for 8-, 10-, and 12-bit digitizers will be highlighted since this hardware is common to most sites

  9. Delta function excitation of waves in the earth's ionosphere

    Science.gov (United States)

    Vidmar, R. J.; Crawford, F. W.; Harker, K. J.

    1983-01-01

    Excitation of the earth's ionosphere by delta function current sheets is considered, and the temporal and spatial evolution of wave packets is analyzed for a two-component collisional F2 layer. Approximations of an inverse Fourier-Laplace transform via saddle point methods provide plots of typical wave packets. These illustrate cold plasma wave theory and may be used as a diagnostic tool since it is possible to relate specific features, e.g., the frequency of a modulation envelope, to plasma parameters such as the electron cyclotron frequency. It is also possible to deduce the propagation path length and orientation of a remote radio beacon.

  10. Environmental accounting: A tool for promoting environmental management in the Niger Delta

    Directory of Open Access Journals (Sweden)

    Ph. D. Uwuigne Uwalomwa

    2012-05-01

    Full Text Available Oil exploration and exploitation has over the last four decades impacted disastrously on the socio-physical environment of the Niger Delta oil-bearing communities in Nigeria. This invariably is responsible for the social unrest in the host communities. In response to various pressures by environmental lobby groups, companies have began to realize the need for the integration of environmental reporting practice in their annual report. To this end, this paper studied exploratively the extent to which the introduction of environmental accounting practice will help in bringing about an improved environmental sustainability and an effective environmental management system in the Niger delta region of Nigeria. The paper concludes that the integration and the disclosure of environmental liabilities will to a large extent reduce the social unrest in these areas. This in return will help organizations to maximize the efficient use of their resources, minimize environmental liabilities and demonstrate a good corporate image. The paper therefore recommends that accountants and environmental experts should pool their skills to form a multi-disciplinary team to address environmental issues.

  11. Transcriptomic profiling of pancreatic alpha, beta and delta cell populations identifies delta cells as a principal target for ghrelin in mouse islets

    DEFF Research Database (Denmark)

    Adriaenssens, Alice E; Svendsen, Berit; Lam, Brian Y H

    2016-01-01

    cytometry and analysed by RNA sequencing. The role of the ghrelin receptor was validated by imaging delta cell calcium concentrations using islets with delta cell restricted expression of the calcium reporter GCaMP3, and in perfused mouse pancreases. RESULTS: A database was constructed of all genes...... expressed in alpha, beta and delta cells. The gene encoding the ghrelin receptor, Ghsr, was highlighted as being highly expressed and enriched in delta cells. Activation of the ghrelin receptor raised cytosolic calcium levels in primary pancreatic delta cells and enhanced somatostatin secretion in perfused...... pancreases, correlating with a decrease in insulin and glucagon release. The inhibition of insulin secretion by ghrelin was prevented by somatostatin receptor antagonism. CONCLUSIONS/INTERPRETATION: Our transcriptomic database of genes expressed in the principal islet cell populations will facilitate...

  12. Geochronology of priority pollutants in sedimentation zones of the Volga and Danube delta in comparison with the Rhine delta

    International Nuclear Information System (INIS)

    Winkels, H.J.; Kroonenberg, S.B.; Lychagin, M.Y.; Marin, G.; Rusakov, G.V.; Kasimov, N.S.

    1998-01-01

    Six sediment cores were taken in sedimentation zones of the Volga river (located in the southern part of the Russian Federation) and, additionally, 6 sediment cores were taken in several lakes (sedimentation zones) in the central and western part of the Danube delta in Romania. Priority pollutants (8 metals, 7 polychlorinated biphenyls and 10 polycyclic aromatic hydrocarbons) were determined in all samples of all cores. Present-day and historical levels of pollutants since the late 1930s were established through the use of radionuclide time tracers ( 137 Cs, 134 Cs). For the persistent metals and polycyclic aromatic hydrocarbons, trends in the concentration profiles during the last 5 decades are described. Low and hardly changing concentrations of As, Cu, Zn and all studied PAHs were observed during the last five decades in the sediments of the Volga river. Recently deposited sediments show slightly increasing levels for the heavy metals Zn and Cr and As in the Volga delta. For the studied metals and PAHs, maximum concentrations were found around 1987 in the sediments of the Danube delta. Sediments deposited around 1940 and recently deposited sediments in the Danube delta showed lower pollutant levels. If the contents of heavy metals, PAHs and PCBs in the aquatic sediments in the deltas of the rivers Rhine, Danube and Volga are compared, it is clear that the Volga delta is and was the cleanest delta during the last 5 decades. Nowadays the contents of heavy metals (except Cu and Ni), PAHs and PCBs in the aquatic sediments of the river Rhine are still highest compared to the other two rivers. The recent load of heavy metals (except Cd and Zn) in the sediments of the river Danube is the highest compared to the other two rivers. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  13. Doubly truncated FosB isoform (Delta2DeltaFosB) induces osteosclerosis in transgenic mice and modulates expression and phosphorylation of Smads in osteoblasts independent of intrinsic AP-1 activity

    DEFF Research Database (Denmark)

    Sabatakos, George; Rowe, Glenn C; Kveiborg, Marie

    2008-01-01

    DeltaFosB and a further truncated isoform (Delta2DeltaFosB) that lacks known transactivation domains but, like DeltaFosB, induces increased expression of osteoblast marker genes. MATERIALS AND METHODS: To test Delta2DeltaFosB's ability to induce bone formation in vivo, we generated transgenic mice......6 expression. CONCLUSIONS: DeltaFosB's AP-1 transactivating function is not needed to induce increased bone formation, and Delta2DeltaFosB may act, at least in part, by increasing Smad1 expression, phosphorylation, and translocation to the nucleus....

  14. Unexpected {delta}{sup 18}O and {delta}{sup 2}H Variability of Groundwater in the Eastern Paris Basin

    Energy Technology Data Exchange (ETDEWEB)

    Gourcy, L.; Petelet-Giraud, E. [BRGM Service EAU, Orleans (France)

    2013-07-15

    The Paris Basin covers about one-third of the total surface area of France. In 2009, two campaigns sampling 25 boreholes tapping Tertiary aquifers were carried out in the Basin. These aquifers are recharged at a similar altitude and the groundwater age is too young to have registered climate change. In the past, regional studies included the use of isotopes to understand groundwater origin and dynamics. Both {delta}{sup 18}O and {delta}{sup 2}H as well as ages (CFC/SF{sub 6)} and chemical components were determined in all collected samples. A noticeable stable isotope 'anomaly' appears in the south-western part of the Basin, where the average {delta}{sup 18}O and {delta}{sup 2}H values are more depleted and do not fit the pattern given by the continental effect in this area. A regional particularity of the spatial distribution of such isotopes in precipitation may be possible, but should be confirmed by additional work. (author)

  15. Delta Cafés (Portugal: Sustainable Business Development

    Directory of Open Access Journals (Sweden)

    Olgierd Swiatkiewicz

    2017-12-01

    Full Text Available In the case study of Delta Cafés we discuss the sustainable development of the Portuguese company and brand over the 55 years of their existence. Delta Cafés has already been analyzed in terms of marketing activity, social responsibility, management control systems, etc. In this paper, we refer to these studies, and we reach the sources, i.e. the information provided by the Delta Cafés itself. Due to the nature of the coffee market and the use of case study methodology, we start the presentation of this case from a broader context, describing the coffee market in the world and characterizing the coffee market in Portugal as well. Then we present the history of the development of the company and the brand Delta Cafés. The paper ends with concluding remarks in which we discuss the issues of social and environmental responsibility in the light of the development of Delta Cafés business and brand strategies. 

  16. Measurement of delta-rays in ATLAS silicon sensors

    CERN Document Server

    The ATLAS collaboration

    2013-01-01

    In the inner detector of the ATLAS experiment at the LHC, $\\delta$-rays originating from particle interactions in the silicon sensors may cause additional hit channels. A method for identifying silicon hit clusters that are enlarged due to the emission of a $\\delta$-ray is presented. Using pp collision data the expectation is confirmed that the $\\delta$-ray production rate depends linearly on the path length of the particle in silicon, independently of layer radius and detector technology. The range of the $\\delta$-rays, which is a property of the material and should not depend on anything else, is indeed found to be constant as a function of detector layer, path length in silicon and momentum of the particle traversing the silicon. As a by-product of this analysis a method is proposed that could correct for the effect of these $\\delta$-rays, and this could be used to improve track reconstruction.

  17. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2015-06-16

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes pre-determining an association of the restricted computer resource and computer-resource-proximal environmental information. Indicia of user-proximal environmental information are received from a user requesting access to the restricted computer resource. Received indicia of user-proximal environmental information are compared to associated computer-resource-proximal environmental information. User access to the restricted computer resource is selectively granted responsive to a favorable comparison in which the user-proximal environmental information is sufficiently similar to the computer-resource proximal environmental information. In at least some embodiments, the process further includes comparing user-supplied biometric measure and comparing it with a predetermined association of at least one biometric measure of an authorized user. Access to the restricted computer resource is granted in response to a favorable comparison.

  18. Is there a self-organization principle of river deltas?

    Science.gov (United States)

    Tejedor, Alejandro; Longjas, Anthony; Foufoula-Georgiou, Efi

    2017-04-01

    River deltas are known to possess a complex topological and flux-partitioning structure which has recently been quantified using spectral graph theory [Tejedor et al., 2015a,b]. By analysis of real and simulated deltas it has also been shown that there is promise in formalizing relationships between this topo-dynamic delta structure and the underlying delta forming processes [e.g., Tejedor et al., 2016]. The question we pose here is whether there exists a first order organizational principle behind the self-organization of river deltas and whether this principle can be unraveled from the co-evolving topo-dynamic structure encoded in the delta planform. To answer this question, we introduce a new metric, the nonlocal Entropy Rate (nER) that captures the information content of a delta network in terms of the degree of uncertainty in delivering fluxes from any point of the network to the shoreline. We hypothesize that if the "guiding principle" of undisturbed deltas is to efficiently and robustly build land by increasing the diversity of their flux pathways over the delta plane, then they would exhibit maximum nonlocal Entropy Rate at states at which geometry and flux dynamics are at equilibrium. At the same time, their nER would be non-optimal at transient states, such as before and after major avulsions during which topology and dynamics adjust to each other to reach a new equilibrium state. We will present our results for field and simulated deltas, which confirm this hypothesis and open up new ways of thinking about self-organization, complexity and robustness in river deltas. One particular connection of interest might have important implications since entropy rate and resilience are related by the fluctuation theorem [Demetrius and Manke, 2005], and therefore our results suggest that deltas might in fact self-organize to maximize their resilience to structural and dynamic perturbations. References: Tejedor, A., A. Longjas, I. Zaliapin, and E. Foufoula

  19. Understanding delta-sigma data converters

    CERN Document Server

    Pavan, Shanti; Temes, Gabor C

    2017-01-01

    This new edition introduces novel analysis and design techniques for delta-sigma (ΔΣ) converters in physical and conceptual terms, and includes new chapters that explore developments in the field over the last decade. This book explains the principles and operation of delta-sigma analog-to-digital converters (ADCs) in physical and conceptual terms in accordance with the most recent developments in the field. The interest of ΔΣ converter designers has shifted significantly over the past decade, due to many new applications for data converters at the far ends of the frequency spectrum. Continuous-time delta-sigma A/D converters with GHz clocks, of both lowpass and bandpass types, are required for wireless applications. At the other extreme, multiplexed ADCs with very narrow (sometimes 10 Hz wide) signal bandwidths, but very high accuracy are needed in the interfaces of biomedical and environmental sensors. To reflect the changing eeds of designers, the second edition includes significant new material on bo...

  20. Electronic theses and dissertations: a review of this valuable resource for nurse scholars worldwide.

    Science.gov (United States)

    Goodfellow, L M

    2009-06-01

    A worldwide repository of electronic theses and dissertations (ETDs) could provide worldwide access to the most up-to-date research generated by masters and doctoral students. Until that international repository is established, it is possible to access some of these valuable knowledge resources. ETDs provide a technologically advanced medium with endless multimedia capabilities that far exceed the print and bound copies of theses and dissertations housed traditionally in individual university libraries. CURRENT USE: A growing trend exists for universities worldwide to require graduate students to submit theses or dissertations as electronic documents. However, nurse scholars underutilize ETDs, as evidenced by perusing bibliographic citation lists in many of the research journals. ETDs can be searched for and retrieved through several digital resources such as the Networked Digital Library of Theses and Dissertations (http://www.ndltd.org), ProQuest Dissertations and Theses (http://www.umi.com), the Australasian Digital Theses Program (http://adt.caul.edu.au/) and through individual university web sites and online catalogues. An international repository of ETDs benefits the community of nurse scholars in many ways. The ability to access recent graduate students' research electronically from anywhere in the world is advantageous. For scholars residing in developing countries, access to these ETDs may prove to be even more valuable. In some cases, ETDs are not available for worldwide access and can only be accessed through the university library from which the student graduated. Public access to university library ETD collections is not always permitted. Nurse scholars from both developing and developed countries could benefit from ETDs.

  1. Secondary electron emission and self-consistent charge transport in semi-insulating samples

    Energy Technology Data Exchange (ETDEWEB)

    Fitting, H.-J. [Institute of Physics, University of Rostock, Universitaetsplatz 3, D-18051 Rostock (Germany); Touzin, M. [Unite Materiaux et Transformations, UMR CNRS 8207, Universite de Lille 1, F-59655 Villeneuve d' Ascq (France)

    2011-08-15

    Electron beam induced self-consistent charge transport and secondary electron emission (SEE) in insulators are described by means of an electron-hole flight-drift model (FDM) now extended by a certain intrinsic conductivity (c) and are implemented by an iterative computer simulation. Ballistic secondary electrons (SE) and holes, their attenuation to drifting charge carriers, and their recombination, trapping, and field- and temperature-dependent detrapping are included. As a main result the time dependent ''true'' secondary electron emission rate {delta}(t) released from the target material and based on ballistic electrons and the spatial distributions of currents j(x,t), charges {rho}(x,t), field F(x,t), and potential V(x,t) are obtained where V{sub 0} = V(0,t) presents the surface potential. The intrinsic electronic conductivity limits the charging process and leads to a conduction sample current to the support. In that case the steady-state total SE yield will be fixed below the unit: i.e., {sigma} {eta} + {delta} < 1.

  2. Levee Seepage Detection in the Sacramento-San Joaquin Delta Using Polarimetric SAR

    Science.gov (United States)

    An, K.; Jones, C. E.; Bekaert, D. P.

    2017-12-01

    The Sacramento-San Joaquin Delta's extensive levee system protects over 2,800 km2 of reclaimed lands and serves as the main irrigation and domestic water supply for the state of California. However, ongoing subsidence and disaster threats from floods and earthquakes make the Delta levee system highly vulnerable, endangering water supplies for 23 million California residents and 2.5 million acres of agricultural land. Levee failure in the Delta can cause saltwater intrusion from San Francisco Bay, reducing water quality and curtailing water exports to residents, commercial users, and farmers. To protect the Delta levee system, it is essential to search for signs of seepage in which water is piping through or beneath levees, which can be associated with deformation of the levees themselves. Until now, in-situ monitoring has largely been applied, however, this is a time-consuming and expensive approach. We use data acquired with NASA's UAVSAR (Uninhabited Aerial Vehicle Synthetic Aperture Radar) airborne radar instrument to identify and characterize levee seepages and associated land subsidence through advanced remote sensing technologies. The high spatial resolution of UAVSAR can help to direct surveys to areas that are likely to be experiencing damage. UAVSAR is an L-band airborne sensor with high signal-to-noise ratio, repeat flight track accuracy, and spatial resolution of 7x7 m2 (for multi-looked products) that is necessary for detailed levee monitoring. The adaptability of radar instruments in their ability to see through smoke, haze, and clouds during the day or night, is especially relevant during disaster events, when cloud cover or lack of solar illumination inhibits traditional visual surveys of damage. We demonstrate the advantages of combining polarimetric radar imagery with geographic information systems (GIS) datasets in locating seepage features along critical levee infrastructure in the Delta for 2009-2016. The ability to efficiently locate potential

  3. Shallow stratigraphy of the Skagit River Delta, Washington, derived from sediment cores

    Science.gov (United States)

    Grossman, Eric E.; George, Douglas A.; Lam, Angela

    2011-01-01

    Sedimentologic analyses of 21 sediment cores, ranging from 0.4 to 9.6 m in length, reveal that the shallow geologic framework of the Skagit River Delta, western Washington, United States, has changed significantly since 1850. The cores collected from elevations of 3.94 to -2.41 m (relative to mean lower low water) along four cross-shore transects between the emergent marsh and delta front show relatively similar environmental changes across an area spanning ~75 km2. Offshore of the present North Fork Skagit River and South Fork Skagit River mouths where river discharge is focused by diked channels through the delta, the entire 5–7-km-wide tidal flats are covered with 1–2 m of cross-bedded medium-to-coarse sands. The bottoms of cores, collected in these areas are composed of mud. A sharp transition from mud to a cross-bedded sand unit indicates that the tidal flats changed abruptly from a calm environment to an energetic one. This is in stark contrast to the Martha's Bay tidal flats north of the Skagit Bay jetty that was completed in the 1940s to protect the newly constructed Swinomish Channel from flooding and sedimentation. North of the jetty, mud ranging from 1 to 2 m thick drapes a previously silt- and sand-rich tidal flat. The silty sand is a sediment facies that would be expected there where North Fork Skagit River sedimentation occurred prior to jetty emplacement. This report describes the compositional and textural properties of the sediment cores by using geophysical, photographic, x-radiography, and standard sediment grain-size and carbon-analytical methods. The findings help to characterize benthic habitat structure and sediment transport processes and the environmental changes that have occurred across the nearshore of the Skagit River Delta. The findings will be useful for quantifying changes to nearshore marine resources, including impacts resulting from diking, river-delta channelization, shoreline development, and natural variations in fluvial

  4. Open source integrated modeling environment Delta Shell

    Science.gov (United States)

    Donchyts, G.; Baart, F.; Jagers, B.; van Putten, H.

    2012-04-01

    In the last decade, integrated modelling has become a very popular topic in environmental modelling since it helps solving problems, which is difficult to model using a single model. However, managing complexity of integrated models and minimizing time required for their setup remains a challenging task. The integrated modelling environment Delta Shell simplifies this task. The software components of Delta Shell are easy to reuse separately from each other as well as a part of integrated environment that can run in a command-line or a graphical user interface mode. The most components of the Delta Shell are developed using C# programming language and include libraries used to define, save and visualize various scientific data structures as well as coupled model configurations. Here we present two examples showing how Delta Shell simplifies process of setting up integrated models from the end user and developer perspectives. The first example shows coupling of a rainfall-runoff, a river flow and a run-time control models. The second example shows how coastal morphological database integrates with the coastal morphological model (XBeach) and a custom nourishment designer. Delta Shell is also available as open-source software released under LGPL license and accessible via http://oss.deltares.nl.

  5. Conflicts and politics in the Tana Delta, Kenya : an analysis of the 2012-2013 clashes and the general and presidential elections 2013

    NARCIS (Netherlands)

    Kirchner, K.

    2013-01-01

    This study connects the topic of natural resource conflicts with political elements, especially elections and looks into clashes between a pastoralist (Orma) and an agricultural (Pokomo) community in Kenya. It analyses the clashes in the Tana delta which escalated in August 2012 from a political

  6. Appraisal of groundwater resources of Ziarat valley using isotopic techniques

    International Nuclear Information System (INIS)

    Ahmad, M.; Akram, W.; Tasneem, M.A.; Rafique, M.

    2009-07-01

    Study of water resources of Ziarat Valley was carried out to investigate groundwater recharge mechanism and effectiveness of delay action dams. Samples of precipitation (rain, snow), dam reservoirs and groundwater (dug wells, tube wells, karezes, springs) were periodically collected from different locations and analyzed for environmental isotopes (/sup 2/H, /sup 3/H, /sup 18/O, /sup 34/S). The data indicate that rainfall and snow samples show wide ranges of delta /sup 2/H and delta /sup 18/O. However, the mean values for these isotopes are -6.4% and -37% respectively. Mean tritium value of rain is 9TU. Delta /sup 2/H and delta /sup 18/O values of dam reservoirs range from -6.7 to +4.9% and -42 to +30% respectively. Average isotopic indices of all the karezes are close to each other. Mean delta /sup 18/O and delta /sup 2/H values of Sandaman Tangi, Faran Tangi and Quaid springs vary from -6.3 to -6% and -40 to -31%. Tritium concentration of Sandaman Tangi and Faran Tangi springs (7 TU) is less than Quaid spring (11TU). Ranges of mean delta /sup 18/O and delta /sup 2/H values of all the groundwater samples (wells, karezes, springs) are -6.6 to -2.2% and -40 to -16% respectively. Delta /sup 34/S values of dissolved sulphates in groundwater vary from -8.5 to -0.8%. In /sup 18/O vs. /sup 2/H plot, most of the groundwater samples lie close to LMWL indicating the meteoric origin. Reservoir water in Pechi Dam shows highly enriched isotopic values in summer due to evaporation. Such enriched values are not depicted by the groundwater in the wells and karezes downstream of the dam. This implies that there is no significant recharge from this dam. Similar is the case of Mana Dam. Vouch Ghouski Dam has some contribution towards groundwater recharge while Warchoom Dam is much effective and makes significant contribution. Results of tritium dating suggest that residence time of groundwater is quite short (only few years). (author)

  7. Raman E sub 1 , E sub 1 + DELTA sub 1 resonance in nonstressed quantum dots of germanium

    CERN Document Server

    Talochkin, A B; Efanov, A V; Kozhemyako, I G; Shumskij, V N

    2001-01-01

    The Raman light scattering on the optical phonons in the nonstressed Ge quantum dots, obtained in the GaAs/ZnSe/Ge/ZnSe structures is studied through the molecular-beam epitaxy. The E sub 1 , E sub 1 + DELTA sub 1 resonance energy shift, connected with quantization of the electron and hole states spectrum in the quantum dots is observed. Application of the simplest localization model with an account of the Ge electron states spectrum made it possible to explain the observed peculiarities

  8. How Rapid Change Affects Deltas in the Arctic Region

    Science.gov (United States)

    Overeem, I.; Bendixen, M.

    2017-12-01

    Deltas form where the river drains into the ocean. Consequently, delta depositional processes are impacted by either changes in the respective river drainage basin or by changes in the regional marine environment. In a warming Arctic region rapid change has occurred over the last few decades in both the terrestrial domain as well as in the marine domain. Important terrestrial controls include 1) change in permafrost possibly destabilizing river banks, 2) strong seasonality of river discharge due to a short melting season, 3) high sediment supply if basins are extensively glaciated, 4) lake outbursts and ice jams favoring river flooding. Whereas in the Arctic marine domain sea ice loss promotes wave and storm surge impact, and increased longshore transport. We here ask which of these factors dominate any morphological change in Arctic deltas. First, we analyze hydrological data to assess change in Arctic-wide river discharge characteristics and timing, and sea ice concentration data to map changes in sea ice regime. Based on this observational analysis we set up a number of scenarios of change. We then model hypothetical small-scale delta formation considering change in these primary controls by setting up a numerical delta model, and combining it dynamically with a permafrost model. We find that for typical Greenlandic deltas changes in river forcing due to ice sheet melt dominate the morphological change, which is corroborated by mapping of delta progradation from aerial photos and satellite imagery. Whereas in other areas, along the North Slope and the Canadian Arctic small deltas are more stable or experienced retreat. Our preliminary coupled model allows us to further disentangle the impact of major forcing factors on delta evolution in high-latitude systems.

  9. Library resources on the Internet

    Science.gov (United States)

    Buchanan, Nancy L.

    1995-07-01

    Library resources are prevalent on the Internet. Library catalogs, electronic books, electronic periodicals, periodical indexes, reference sources, and U.S. Government documents are available by telnet, Gopher, World Wide Web, and FTP. Comparatively few copyrighted library resources are available freely on the Internet. Internet implementations of library resources can add useful features, such as full-text searching. There are discussion lists, Gophers, and World Wide Web pages to help users keep up with new resources and changes to existing ones. The future will bring more library resources, more types of library resources, and more integrated implementations of such resources to the Internet.

  10. The harmoniation of cultural heritage and architectural conseration needs with socio-economic requirements of rural habitat in Danube Delta

    Directory of Open Access Journals (Sweden)

    SELA Florentina

    2016-12-01

    Full Text Available The paper present a study of cultural heritage of rural landscape in Danube Delta Biosphere Reserve focuses on cultural landscapes that reflect traditional lifestyle of the locals, activities of deltas’ resource sustainable exploitation, creating visual elements in the rural landscape, especially on traditional buildings, fishermens’ temporary shelters from fishing areas and other traditional activities. In order to highlight the necessity of cultural heritage harmonization and architectural conservation with the socio-economic requirements of rural habitat in Danube Delta were made some field activities through different methods of field investigation, like structured and semistructured interviews, questionnaires, focus groups. In Danube Delta villages, the changes imposed by the touristic function of most of existing or new construction have produced important changes in the architectural landscape of existing settlements impending danger of destroying traditional architectural values which demonstrates on the one hand the personality and inovation spirit of local people in their constructions, particularly in the use of local materials, and on the other hand gives a specific area feature that blends perfectly with the natural landscape. Danube Delta, the space of complex features in terms of cultural values, characterized as open gate of cultural interference, is the area that can provide options to balance cohabitation and cultural heritage.

  11. Using Fishers Knowledge in Community Based Fisheries Management in the River Nun Estuary, Niger Delta

    Directory of Open Access Journals (Sweden)

    Ngodigha Sabina

    2018-02-01

    Full Text Available A study of fishers’ knowledge in community based fisheries management practices in the Nun River estuary were conducted to assess the contribution of fishers’ knowledge to fisheries resources conservation. The total number of fishers that operated in the area were 390, and 221 fishers were interviewed based on a minimum of 10 years fishing experience using the socio-ecological approach. The laws introduced are banned on the use of mesh size less than five cm and banned on chemical fishing. Fishers caught using chemicals to fish were arrested and handed over to the police for prosecution. The management method has enhanced conservation of fisheries’ resources, which is a major source of livelihood for the people. It is therefore pertinent to introduce community based laws to check over exploitation of fisheries’ resources in fishing communities in the Niger Delta.

  12. An automated technique for measuring deltaD and delta18O values of porewater by direct CO2 and H2 equilibration.

    Science.gov (United States)

    Koehler, G; Wassenaar, L I; Hendry, M J

    2000-11-15

    The stable-oxygen and -hydrogen isotopic values (deltaD, delta18O) of porewater in geologic media are commonly determined on water obtained by extraction techniques such as centrifugation, mechanical squeezing, vacuum heating and cryogenic microdistillation, and azeotropic distillation. Each of these techniques may cause isotopic fractionation as part the extraction process and each is laborious. Here we demonstrate a new approach to obtain automated, high-precision deltaD and delta18O measurements of porewater in geologic sediments by direct H2- and CO2-porewater equilibration using a modified commercial CO2-water equilibrator. This technique provides an important and cost-effective improvement over current extraction methods, because many samples can be rapidly analyzed with minimal handling, thereby reducing errors and potential for isotopic fractionation. The precision and accuracy of direct H2- and CO2-porewater equilibration is comparable to or better than current porewater extraction methods. Finally, the direct equilibration technique allows investigators to obtain high-resolution (cm scale) porewater deltaD and delta18O profiles using cores from individual boreholes, eliminating the need for costly piezometers or conventional porewater extractions.

  13. An integrated framework to assess future livelihood and poverty changes in deltas: an application to coastal Bangladesh

    Science.gov (United States)

    Nicholls, Robert J.; Lazar, Attlia; Payo, Andres; Adams, Helen; Salehin, Mashfiqus; Haque, Anisul; Clarke, Derek; Bricheno, Lucy; Fernandes, Jose; Rahman, Mofizur; Ahmed, Ali; Streatfield, Kim

    2016-04-01

    Coastal deltas represent some of the most densely populated areas in the world. A good example is the coastal zone of Bangladesh where there are more than 1000 people/km2 in the rural areas. Livelihoods, food security and poverty in this area is strongly dependent on natural resources affected by several factors including climate variability and change, upstream river flow modifications, commercial fish catches in the Bay of Bengal, and engineering interventions such as polderisation. The scarcity of fresh water, saline water intrusion and natural disasters (e.g. river flooding, cyclones and storm surges) have negative impact on drinking water availability and crop irrigation potential. This severely affects land use and livelihood opportunities of the coastal population. Hydro-environmental changes can be especially detrimental for the well-being of the poorest households that are highly dependent on natural resources. The ESPA Deltas project aims to holistically examine the interaction between the coupled bio-physical environment and the livelihoods of these poor populations in coastal Bangladesh. Here we describe a new integrated model that allows the long-term analysis of the possible changes in this system by linking projected changes in physical processes (e.g. river flows, nutrients), with productivity (e.g. fish catches, rice production), social processes (e.g. access, property rights, migration) and governance/management (e.g. fisheries, agriculture, water and land use management). This includes the development and application of a range of scenarios, including expert-derived scenarios on issues such as climate change, and stakeholder-derived scenarios on more local issues in Bangladesh. This integrated approach is designed to provide Bangladeshi policy makers with science-based evidence of possible development trajectories within the coastal delta plain over timescales up to 50 years, including the likely robustness of different governance options on

  14. The low-temperature structures of Hgsub(3-delta)SbF6 and Hgsub(3-delta)TaF6

    International Nuclear Information System (INIS)

    Tun, Z.; Brown, I.D.

    1986-01-01

    The Hg chains in both Hgsub(3-delta)SbF 6 and Hgsub(3-delta)TaF 6 order below room temperature. Down to about 190 K the ordering results from the interaction between parallel chains. It is short range and is different for the two compounds. Below 190 K both compounds transform to an isostructural long-range-ordered phase which is driven by the interaction between perpendicular chains. The structure of this phase in both compounds has been determined. Hgsub(3-delta)SbF 6 at 173 K, delta=0.134(1), Msub(r)=810.6(2). It is monoclinic but pseudotetragonal with I4 1 /amd, a=7.655(1), c=12.558(1) A, V=735.9(2) A 3 , Z=4, Dsub(x)=7.314(3) Mg m -3 , graphite-monochromated Mo Kα radiation, lambda=0.71069 A, μ=64.8 mm -1 , F(000)=1337.1(3). Hgsub(3-delta)TaF 6 at 150 K is isostructural but has delta=0.142(1), Msub(r)=868.2(2), a=7.634(1), c=12.610(2) A, V=734.9(2) A, Dsub(x)=7.844(3) Mg m -3 , μ=76.4 mm -1 , F(000)=1422.6(3). Comparison of the low-temperature structures with those at room temperature shows that the thermal contraction results from the shortening of interatomic distances associated with the weak bonds, with the result that the MF 6 (M=Sb, Ta) host lattice shrinks more than the Hg chains. Variation of the atomic displacement parameters with temperature indicates that the large librational displacements of the MF 6 ion result from thermal motion rather than static disorder. (orig.)

  15. Experimental river delta size set by multiple floods and backwater hydrodynamics.

    Science.gov (United States)

    Ganti, Vamsi; Chadwick, Austin J; Hassenruck-Gudipati, Hima J; Fuller, Brian M; Lamb, Michael P

    2016-05-01

    River deltas worldwide are currently under threat of drowning and destruction by sea-level rise, subsidence, and oceanic storms, highlighting the need to quantify their growth processes. Deltas are built through construction of sediment lobes, and emerging theories suggest that the size of delta lobes scales with backwater hydrodynamics, but these ideas are difficult to test on natural deltas that evolve slowly. We show results of the first laboratory delta built through successive deposition of lobes that maintain a constant size. We show that the characteristic size of delta lobes emerges because of a preferential avulsion node-the location where the river course periodically and abruptly shifts-that remains fixed spatially relative to the prograding shoreline. The preferential avulsion node in our experiments is a consequence of multiple river floods and Froude-subcritical flows that produce persistent nonuniform flows and a peak in net channel deposition within the backwater zone of the coastal river. In contrast, experimental deltas without multiple floods produce flows with uniform velocities and delta lobes that lack a characteristic size. Results have broad applications to sustainable management of deltas and for decoding their stratigraphic record on Earth and Mars.

  16. A Modal Logic for Abstract Delta Modeling

    NARCIS (Netherlands)

    F.S. de Boer (Frank); M. Helvensteijn (Michiel); J. Winter (Joost)

    2012-01-01

    htmlabstractAbstract Delta Modeling is a technique for implementing (software) product lines. Deltas are put in a partial order which restricts their application and are then sequentially applied to a core product in order to form specific products in the product line. In this paper we explore the

  17. Four new Delta Scuti stars

    Science.gov (United States)

    Schutt, R. L.

    1991-01-01

    Four new Delta Scuti stars are reported. Power, modified into amplitude, spectra, and light curves are used to determine periodicities. A complete frequency analysis is not performed due to the lack of a sufficient time base in the data. These new variables help verify the many predictions that Delta Scuti stars probably exist in prolific numbers as small amplitude variables. Two of these stars, HR 4344 and HD 107513, are possibly Am stars. If so, they are among the minority of variable stars which are also Am stars.

  18. ELECTRONIC EDUCATIONAL RESOURCES FOR ONLINE SUPPORT OF MODERN CHEMISTRY CLASSES IN SPECIALIZED SCHOOL

    Directory of Open Access Journals (Sweden)

    Maria D. Tukalo

    2013-09-01

    Full Text Available This article contains material of some modern electronic educational resources that can be used via the Internet to support the modern chemistry classes in specialized school. It was drawn attention to the educational chemical experiments as means of knowledge; simulated key motivational characteristics to enhance students interest for learning subjects, their cognitive and practical activity in the formation of self-reliance and self-creative; commented forecasts for creating of conditions to enhance the creative potential of students in a modern learning environment.

  19. Delta Evolution at Røde Elv, Disko Island, Greenland

    Science.gov (United States)

    Kroon, A.; Arngrimson, J.; Bendixen, M.; Sigsgaard, C.

    2017-12-01

    Ice, snow and freezing temperatures have a large impact on coastal morphodynamics in Arctic polar environments. A recent warming of the Arctic climate induces many changes along the arctic shorelines. Sea-levels are rising due to thermal expansion and due to an increased fresh water flux from the glaciers and land ice masses. At the same time, the ice coverage of the coastal waters reduces and the open water periods in summer extend. There is a strong seasonal variation with open waters and active rivers in summer and ice-covered coastal waters and inactive rivers in winter. Coastal processes by waves and tides are thus limited to the summer and early fall. Besides, there is also a strong daily variation in fluvial discharges due to the daily variations in glacier melt with maximum melt in the afternoon and minimum values at night. At the same time, the actual flux of the river to the coastal bay is influenced by the tidal phase. Low tides will enhance the transport to the delta front, while high tides will create stagnant waters over the delta plain. The delta of the Røde Elv is located in southwestern Disko Island in west Greenland. It has a relatively small (ca. 101 km2) and partly glaciated drainage basin (ca. 20%) and its sediments consist of a mixture of basaltic sands and gravels. The Røde Elv delta is located at the end of a pro-glacial and fluvial valley at about 20 km from the glacier. The shores of the delta are reworked by waves, predominantly from southwestern, southern (largest fetch, over 50 km), and southeastern directions. The environment has a micro- to meso- tidal range with a spring tidal range of 2.7 m. The morphologic changes on the delta over the last decades clearly showed a seaward extension of the delta and a periodic shift in the location of the main delta channel. In this presentation, we focus on quantification of water discharges and suspended sediment fluxes to the Røde Elv delta in western Greenland, and on the morphological

  20. On the upstream boundary of electron foreshocks in the solar wind

    Science.gov (United States)

    Zimbardo, G.; Veltri, P.

    1995-01-01

    The upstream boundary of electron foreshocks is defined as the path of the fastest electrons reflected by collisionless shocks and moving along the magnetic field in the solar wind. Considerable levels of magnetic fluctuations are found in these regions of the solar wind, and their effect is to create both a broadening and a fine structure of the electron foreshock boundary. The magnetic structure is studied by means of a 3-D numerical simulation of a turbulent magnetic field. Enhanced, anomalous diffusion is found, (Delta x(exp 2)) varies as s(sup alpha), where alpha is greater than 1 for typical values of the parameters (here, Delta x(exp 2) is the mean square width of the tangent magnetic surface and s is the field line length). This corresponds to a Levy flight regime for the magnetic field line random walk, and allows very efficient electron propagation perpendicular to the magnetic field. Implications on the observations of planetary foreshocks and of the termination shock foreshock are considered.

  1. Implications for future survival of delta smelt from four climate change scenarios for the Sacramento–San Joaquin Delta, California

    Science.gov (United States)

    Brown, Larry R.; Bennett, William A.; Wagner, R. Wayne; Morgan-King, Tara; Knowles, Noah; Feyrer, Frederick; Schoellhamer, David H.; Stacey, Mark T.; Dettinger, Mike

    2013-01-01

    Changes in the position of the low salinity zone, a habitat suitability index, turbidity, and water temperature modeled from four 100-year scenarios of climate change were evaluated for possible effects on delta smelt Hypomesus transpacificus, which is endemic to the Sacramento–San Joaquin Delta. The persistence of delta smelt in much of its current habitat into the next century appears uncertain. By mid-century, the position of the low salinity zone in the fall and the habitat suitability index converged on values only observed during the worst droughts of the baseline period (1969–2000). Projected higher water temperatures would render waters historically inhabited by delta smelt near the confluence of the Sacramento and San Joaquin rivers largely uninhabitable. However, the scenarios of climate change are based on assumptions that require caution in the interpretation of the results. Projections like these provide managers with a useful tool for anticipating long-term challenges to managing fish populations and possibly adapting water management to ameliorate those challenges.

  2. Selection and Evaluation of Electronic Resources

    Directory of Open Access Journals (Sweden)

    Doğan Atılgan

    2013-11-01

    Full Text Available Publication boom and issues related to controlling and accession of printed sources have created some problems after World War II. Consequently, publishing industry has encountered the problem of finding possible solution for emerged situation. Industry of electronic publishing has started to improve with the rapid increase of the price of printed sources as well as the problem of publication boom. The first effects of electronic publishing were appeared on the academic and scholarly publications then electronic publishing became a crucial part of all types of publications. As a result of these developments, collection developments and service policies of information centers were also significantly changed. In this article, after a general introduction about selection and evaluation processes of electronic publications, the subscribed databases by a state and a privately owned university in Turkey and their usage were examined.

  3. Morphodynamics of a cyclic prograding delta: the Red River, Vietnam

    NARCIS (Netherlands)

    Maren, D.S. van

    2004-01-01

    River deltas are inhabited by over 60% of the world population, and are, consequently, of paramount agricultural and economical importance. They constitute unique wetland envi ronments which gives river deltas ecological importance as well. Additionally, many deltas contain large accumulations of

  4. Changes to subaqueous delta bathymetry following a high river flow event, Wax Lake Delta, LA, USA

    Science.gov (United States)

    Whaling, A. R.; Shaw, J.

    2017-12-01

    Sediment transport capacity is increased during high river flow (flood) events which are characterized by discharges that exceed the 15 year median daily statistic. The Wax Lake Delta (WLD) in coastal Louisiana has experienced 19 of these high flow events in the past 20 years, yet the depositional patterns of single floods are rarely measured in a field-scale deltaic setting. We characterize flood deposition and erosion patterns on the subaqueous portion of the WLD by differencing two Digital Elevation Models (DEMs) constructed from bathymetric surveys before and after the third largest flood in the WLD's recorded history. The total suspended sediment discharge for the 496 day inter-survey period was 2.14x107 cubic meters measured 21 km upstream of the delta apex. The difference map showed 1.06x107 cubic meters of sediment was deposited and 8.2x106 cubic meters was eroded, yielding 2.40x106 cubic meters of net deposition in the survey area ( 79.7 km2 ). Therefore the average deposition rate was 0.061 mm/day. Channel planform remained relatively unchanged for five out of six distributary passes however Gadwall Pass experienced a maximum channel displacement of 166 m ( 1 channel width) measured from the thalweg centerline. Channel tip extension was negligible. In addition, channel displacement was not concentrated at any portion along the channel centerline. Maximum erosion occurred within channel margins and increased upstream whereas maximum deposition occurred immediately outside the channel margins. Sediment eroded from the survey area was either subsequently re-deposited or transported out of the system. Our results show that up to 77.4% of deposition in the survey area originated from sediment eroded during the flood. Surprisingly, only 11.2% of the total suspended sediment discharge was retained in the subaqueous portion of the delta after the flood. We conclude that a high flow event does not produce channel progradation. Rather, high flow causes delta

  5. An Exploratory study on the use of LibAnswers to Resolve, Track and Monitor Electronic Resources Issues: The KAUST Library experience

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    An Exploratory study on KAUST library use of LibAnswers in resolving electronic resources questions received in LibAnswers. It describes the findings of the questions received in LibAnswers. The author made suggestions based on the findings to improve the reference services in responding to e-resources questions.

  6. An Exploratory study on the use of LibAnswers to Resolve, Track and Monitor Electronic Resources Issues: The KAUST Library experience

    KAUST Repository

    Ramli, Rindra M.

    2017-05-03

    An Exploratory study on KAUST library use of LibAnswers in resolving electronic resources questions received in LibAnswers. It describes the findings of the questions received in LibAnswers. The author made suggestions based on the findings to improve the reference services in responding to e-resources questions.

  7. Exploring for geothermal resources in Greece

    Energy Technology Data Exchange (ETDEWEB)

    Mendrinos, Dimitrios; Choropanitis, Ioannis; Polyzou, Olympia; Karytsas, Constantine [Centre for Renewable Energy Sources and Saving (CRES), 19th km Marathon Avenue, 19009 Pikermi (Greece)

    2010-03-15

    In Greece the geothermal areas are located in regions of Quaternary or Miocene volcanism and in continental basins of high heat flow. The existence of high-temperature (>200 C) resources has been proven by deep drilling on the islands of Milos and Nisyros and inferred on the island of Santorini by its active volcanism. Elsewhere, geological investigations, geochemical analyses of thermal springs and shallow drilling have identified many low-temperature (<100 C) reservoirs, utilized for spas and greenhouse/soil heating. Ternary K-Na-Mg geothermometer data suggest deep, medium-temperature resources (100-200 C) in Sousaki, the islands of Samothraki, Chios and Lesvos, in the basins of Nestos River Delta and Alexandroupolis and in the graben of Sperchios River. In the basins of northern Greece these resources are also inferred from deep oil exploration well data. (author)

  8. Electron interactions with nuclei. Progress report

    International Nuclear Information System (INIS)

    1986-07-01

    Research includes work at SLAC, Bates, and Saclay research facilities. The high energy program at SLAC concerns inclusive electron scattering from nuclei, electroexcitation of the delta in nuclei, and the design of an electron detection system for the SLAC 1.6 GeV/c magnetic spectrometer. The high energy program at Bates includes quasielastic electron scattering from 1 H, 2 H, 3 He, and 4 He, and electron scattering from 3 H and 3 He. Nuclear structure studies are based on high resolution inelastic electron scattering and include electron scattering from 208 Pb and mercury isotopes, charge densities from low lying states in 86 Sr, and magnetization densities of 205 Tl and 207 Pb. (DWL) 72 refs., 29 figs., 1 tab

  9. The level of the usage of the human resource information system and electronic recruitment in Croatian companies

    Directory of Open Access Journals (Sweden)

    Snježana Pivac

    2014-12-01

    Full Text Available Performing business according to contemporary requirements influences companies for continuous usage of modern managerial tools, such as a human resource information system (HRIS and electronic recruitment (ER. Human resources have been recognised as curtail resources and the main source of a competitive advantage in creation of successful business performance. In order to attract and select the top employees, companies use quality information software for attracting internal ones, and electronic recruitment for attracting the best possible external candidates. The main aim of this paper is to research the level of the usage of HRIS and ER within medium-size and large Croatian companies. Moreover, the additional aim of this paper is to evaluate the relationship among the usage of these modern managerial tools and the overall success of human resource management within these companies. For the purpose of this paper, primary and secondary research has been conducted in order to reveal the level of the usage of HRIS and ER as well as the overall success of human resource management in Croatian companies. The companies’ classification (HRIS and ER is done by using the non-hierarchical k-means cluster method as well as the nonparametric Kruskal Wallis test. Further, the companies are ranked by the multicriteria PROMETHEE method. Relevant nonparametric tests are used for testing the overall companies’ HRM. Finally, binary logistic regression is estimated, relating binary variable HRM and HRIS development. After detailed research, it can be concluded that large Croatian companies apply HRIS in majority (with a positive relation to HRM performance, but still require certain degrees of its development.

  10. The electronic encapsulation of knowledge in hydraulics, hydrology and water resources

    Science.gov (United States)

    Abbott, Michael B.

    The rapidly developing practice of encapsulating knowledge in electronic media is shown to lead necessarily to the restructuring of the knowledge itself. The consequences of this for hydraulics, hydrology and more general water-resources management are investigated in particular relation to current process-simulation, real-time control and advice-serving systems. The generic properties of the electronic knowledge encapsulator are described, and attention is drawn to the manner in which knowledge 'goes into hiding' through encapsulation. This property is traced in the simple situations of pure mathesis and in the more complex situations of taxinomia using one example each from hydraulics and hydrology. The consequences for systems architectures are explained, pointing to the need for multi-agent architectures for ecological modelling and for more general hydroinformatics systems also. The relevance of these developments is indicated by reference to ongoing projects in which they are currently being realised. In conclusion, some more general epistemological aspects are considered within the same context. As this contribution is so much concerned with the processes of signification and communication, it has been partly shaped by the theory of semiotics, as popularised by Eco ( A Theory of Semiotics, Indiana University, Bloomington, 1977).

  11. Electron beam position stabilization with a piezo-electric optical correction system

    CERN Document Server

    Averett, T; McKeown, R D; Pitt, M

    1999-01-01

    A piezo-electrically controlled optical correction system was successfully used to reduce the helicity-correlated pulse-to-pulse position differences of a laser spot to better than +-100 nm at a pulse rate of 600 Hz. Using a simple feedback algorithm, average position differences of DELTA x-bar=-3.5+-4.2 nm and DELTA y-bar=2.6+-6.6 nm were obtained over a 6 h period. This optical correction system was successfully used in the polarized electron source at the Bates Linear Accelerator Center to stabilize the position of the electron beam during the recent SAMPLE experiment. Because this experiment measures a parity violating signal at the 10 sup - sup 6 level, it is sensitive to systematic effects which are correlated with the helicity of the incident electrons. One potentially large systematic effect is the helicity-correlated motion of the incident electron beam. By using this optical correction system, electron beam position differences at the location of the experiment were routinely kept well below +-100 n...

  12. Haematological and genetic features of delta beta-thalassaemia in Pakistan

    International Nuclear Information System (INIS)

    Ahmad, S.; Anwar, M.

    2006-01-01

    Objective: To describe the hematological and genetic features of delta beta-thalassaemia in Pakistani patients. Design: Descriptive case series. Place and Duration of Study: Department of Pathology, PNS Shifa, Karachi and Department of Hematology, Armed Forces Institute of Pathology, Rawalpindi, from January 1994 to April 2004. Patients and Methods: Thirteen individuals from six unrelated Pakistani families with a hematological diagnosis of delta beta-thalassaemia were studied. A brief clinical history, and the results of blood counts, absolute values, Hb-F, Hb-A/sub 2/, and hemoglobin electrophoresis were recorded. The DNA from each subject was first screened for the delta beta-thalassaemia mutations found in the Pakistani population. The samples were then screened for the Invl Del sup G/gamma(sup A/gamma delta beta). Results: The subjects included six heterozygote, six homozygotes and one compound heterozygote of delta beta and delta beta-thalassaemia. All heterozygote and 4/6 homozygotes were asymptomatic. One homo zygote had thalassaemia intermedia while another had transfusion dependent anemia. The mean Hb, TRBC, MCV, MCH, Hb-F and Hb-A/sub 2/ in delta beta-thalassaemia heterozygote were 11.6 g/dl, 5.37 x 1012/L, 70.9 fl, and 21.7 pg, 14% and 2.6% respectively. The same values in the four un transfused homo zygote were 10.6 g/dl, 5.34x1012/L, 69.211, and 20.8pg, 100% and 0% respectively. The mutation analysis revealed that all 13 individuals had the same Invl Del sup G/gamma(sup A/gamma delta beta). Conclusion: delta beta-thalassaemia is a rare disorder in Pakistan. Although the clinical picture is very mild its combination with delta beta-thalassaemia trait can produce a sever transfusion dependent thalassaemia. The DNA based diagnosis is possible in the prenatal as well as the postnatal period. (author)

  13. Modern sedimentation and morphology of the subaqueous Mekong Delta, Southern Vietnam

    Science.gov (United States)

    Unverricht, Daniel; Szczuciński, Witold; Stattegger, Karl; Jagodziński, Robert; Le, Xuan Thuyen; Kwong, Laval Liong Wee

    2013-11-01

    The Mekong River Delta is among the Asian mega-deltas and is influenced by various factors including tides (meso-tidal system), waves, coastal currents, monsoon-driven river discharge and human impact (agriculture, fishing, sand dredging, tourism). The present study aims to document the seafloor relief, sediment distribution and sediment accumulation rates to interpret modern sediment transport directions and main sedimentation processes in the subaqueous Mekong Delta. The major results of this investigation include the detection of two delta fronts 200 km apart, one at the mouth of the Bassac River (the biggest branch of the Mekong Delta) and the other around Cape Ca Mau (most south-western end of the Mekong Delta). Additionally, a large channel system runs in the subaqueous delta platform parallel to the shore and between the two fronts. The sediment accumulation rates vary greatly according to the location in the subaqueous delta and have reached up to 10 cm/yr for the last century. A cluster analysis of surface sediment samples revealed two different sediment types within the delta including a well-sorted sandy sediment and a poorly sorted, silty sediment. In addition, a third end member with medium to coarse sand characterised the distant parts of the delta at the transition to the open shelf. The increase of organic matter and carbonate content to the bottom set area and other sedimentary features such as shell fragments, foraminiferas and concretions of palaeo-soils that do not occur in delta sediments, supported grain size-based classification. Beginning in front of the Bassac River mouth, sedimentary pattern indicates clockwise sediment transport alongshore in the western direction to a broad topset area and the delta front around Cape Ca Mau. Our results clearly show the large lateral variability of the subaqueous Mekong Delta that is further complicated by strong monsoon-driven seasonality. River, tidal and wave forcing vary at local and seasonal scales

  14. River Delta Subsidence Measured with Interferometric Synthetic Aperture Radar (InSAR)

    Science.gov (United States)

    Higgins, Stephanie

    This thesis addresses the need for high-resolution subsidence maps of major world river deltas. Driven by a combination of rising water, sediment compaction, and reduced sediment supply due to damming and flood control, many deltas are sinking relative to sea level. A lack of data constraining rates and patterns of subsidence has made it difficult to determine the relative contributions of each factor in any given delta, however, or to assess whether the primary drivers of land subsidence are natural or anthropogenic. In recent years, Interferometric Synthetic Aperture Radar (InSAR) has emerged as a satellite-based technique that can map ground deformation with mm-scale accuracy over thousands of square kilometers. These maps could provide critical insight into the drivers of subsidence in deltas, but InSAR is not typically applied to non-urban delta areas due to the difficulties of performing the technique in wet, vegetated settings. This thesis addresses those difficulties and achieves high-resolution measurements of ground deformation in rural deltaic areas. Chapter 1 introduces the processes that drive relative sea level rise in river deltas and investigates open questions in delta subsidence research. Chapter 2 assesses the performance of InSAR in delta settings and reviews interferogram generation in the context of delta analysis, presenting delta-specific processing details and guiding interpretation in these challenging areas. Chapter 3 applies Differential (D-) InSAR to the coast of the Yellow River Delta in China. Results show that subsidence rates are as high as 250 mm/y due to groundwater extraction at aquaculture facilities, a rate that exceeds local and global average sea level rise by nearly two orders of magnitude and suggests a significant hazard for Asian megadeltas. Chapter 4 applies interferometric stacking and Small Baseline Subset (SBAS)-InSAR to the Ganges-Brahmaputra Delta, Bangladesh. Results show that stratigraphy controls subsidence in

  15. The Great Diversion: Danube Delta under Human Control (Invited)

    Science.gov (United States)

    Giosan, L.

    2009-12-01

    Many deltas around the world are suffering from sediment deficits that render them unstable to current and predicted rates of sea level rise. One solution proposed to alleviate the complete or partial drowning of such deltas is the use of river diversions to increase the quantity of sediment supplied to the delta plain to support marsh accretion. We examine the results of a half century old program of diversion in the Danube delta that led to the creation of an extensive diversion channel network akin in scope and size to a natural deltaic network. Danube’s importance as a shipping route increased after the Crimean War in the 1850s; the European Danube Commission was charged with maintaining the Sulina distributary as a shipping channel until 1940s. In the same period, several canals were dug to aid fishing in lakes and bring freshwater to brackish lagoons. After World War II, Communist authorities dramatically increased the number of canals for fishing, fish-farming and reed harvesting. New data on sedimentation rates and estimates of sediment fluxes suggest that the intensive canalization in the second half of the 20th Century led to increased sediment deposition that compensated the decreasing sediment discharge linked to damming within the internal fluvial part of the delta; however, the external marine delta has become increasingly sediment starved during the same interval. We emphasize the similarities and contrasts between the “human-controlled” and natural deltaic channel networks of the Danube delta and discuss the sustainability of the delta as a sediment budget problem within a sea level rise context.

  16. Population dynamics, delta vulnerability and environmental change: comparison of the Mekong, Ganges–Brahmaputra and Amazon delta regions

    OpenAIRE

    Szabo, S.; Brondizio, E.; Renaud, F.G.; Hetrick, S.; Nicholls, R.; Matthews, Z.; Tessler, Z; Tejedor, A; Sebesvari, Z; Foufoula-Georgiou, E; da Costa, S; Dearing, J.A.

    2016-01-01

    Tropical delta regions are at risk of multiple threats including relative sea level rise and human alterations, making them more and more vulnerable to extreme floods, storms, surges, salinity intrusion, and other hazards which could also increase in magnitude and frequency with a changing climate. Given the environmental vulnerability of tropical deltas, understanding the interlinkages between population dynamics and environmental change in these regions is crucial for ensuring efficient pol...

  17. RESEARCH OF INFLUENCE OF QUALITY OF ELECTRONIC EDUCATIONAL RESOURCES ON QUALITY OF TRAINING WITH USE OF DISTANCE TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    H. M. Kravtsov

    2013-03-01

    Full Text Available Communication improving of educational processes requires today new approaches to the management arrangements and forming of educational policy in the field of distance learning, which is based on the use of modern information and communication technologies. An important step in this process is the continuous monitoring of the development and implementation of information technology and, in particular, the distance learning systems in higher educational establishments. The main objective of the monitoring is the impact assessment on the development of distance learning following the state educational standards, curricula, methodical and technical equipment and other factors; factors revelation that influence the implementation and outcomes of distance learning; results comparison of educational institution functioning and distance education systems in order to determine the most efficient ways of its development. The paper presents the analysis results of the dependence of the quality of educational services on the electronic educational resources. Trends in educational services development was studied by comparing the quality influence of electronic educational resources on the quality of educational services of higher pedagogical educational institutions of Ukraine as of 2009-2010 and 2012-2013. Generally, the analysis of the survey results allows evaluating quality of the modern education services as satisfactory and it can be said that almost 70% of the success of their future development depends on the quality of the used electronic educational resources and distance learning systems in particular.

  18. Quantum-mechanical analysis of low-gain free-electron laser oscillators

    Science.gov (United States)

    Fares, H.; Yamada, M.; Chiadroni, E.; Ferrario, M.

    2018-05-01

    In the previous classical theory of the low-gain free-electron laser (FEL) oscillators, the electron is described as a point-like particle, a delta function in the spatial space. On the other hand, in the previous quantum treatments, the electron is described as a plane wave with a single momentum state, a delta function in the momentum space. In reality, an electron must have statistical uncertainties in the position and momentum domains. Then, the electron is neither a point-like charge nor a plane wave of a single momentum. In this paper, we rephrase the theory of the low-gain FEL where the interacting electron is represented quantum mechanically by a plane wave with a finite spreading length (i.e., a wave packet). Using the concepts of the transformation of reference frames and the statistical quantum mechanics, an expression for the single-pass radiation gain is derived. The spectral broadening of the radiation is expressed in terms of the spreading length of an electron, the relaxation time characterizing the energy spread of electrons, and the interaction time. We introduce a comparison between our results and those obtained in the already known classical analyses where a good agreement between both results is shown. While the correspondence between our results and the classical results are shown, novel insights into the electron dynamics and the interaction mechanism are presented.

  19. Biomass and Carbon Sequestration in Community Mangrove Plantations and a Natural Regeneration Stand in the Ayeyarwady Delta, Myanmar

    Science.gov (United States)

    Thant, Y. M.; Kanzaki, M.; nil

    2011-12-01

    Mangroves in the Ayeyarwady Delta is one of the most threatened ecosystems, and is rapidly disappearing as in many tropical countries. The deforestation and degradation of mangrove forest in the Ayeryarwady Delta results in the shortage of wood resources and declining of environmental services that have been provided by the mangrove ecosystem. Cyclone Nargis struck the Ayeyarwady Delta on 2 May 2008 with an intensity unprecedented in the history of Myanmar. The overexploitation of mangroves because of local demands for fuel wood and charcoal and the conversion of mangrove forest land into agricultural land or shrimp farms over the past decades have increased the loss of human life and the damage to settlements caused by the Cyclone.The biomass study was conducted in September of 2006 in Bogale Township in the Ayeyarwady Delta and continued monitoring in September of each year from 2007 to 2010. Above and below ground biomass was studied in six years old mangrove plantations of Avicenia marina (Am), Avicenia officinalis (Ao) and Sonneratia apetala (Sa) and a naturally regenerated stand under regeneration improving felling operation (NR: consists of Ceriops decandra, Bruguiera sexangula, and Aegicerus corniculatum) protected for seven years since 2000. These stands were established by small-scale Community Forestry scheme on abandoned paddy fields where natural mangroves once existed. Common allometric equations were developed for biomass estimation by performing regressions between dry weights of trees as dependent variables and biometric parameters such as stem diameter, height and wood density as independent variables. The above and below ground biomass in NR stand (70 Mg ha-1 and 104 Mg ha-1) was the greatest (P mangrove plantation and induced natural regeneration as a carbon sequestration tool. The establishment of mangrove plantations appeared to be one measure for reducing the risk of cyclone damage after the Cyclone Nargis. This may reduce future human loss

  20. Electronic structure of p type Delta doped systems; Estructura electronica de sistemas dopadas con Delta de tipo p

    Energy Technology Data Exchange (ETDEWEB)

    Gaggero S, L.M.; Perez A, R. [Departamento de Fisica de los Materiales, Universidad Nacional de Educacion a Distancia, Senda del Rey s/n, 28040 Madrid (Spain)

    1998-12-31

    We summarize of the results obtained for the electronic structure of quantum wells that consist in an atomic layer doped with impurities of p type. The calculations are made within the frame worth of the wrapper function approach to independent bands and with potentials of Hartree. We study the cases reported experimentally (Be in GaAs and B in Si). We present the levels of energy, the wave functions and the rate of the electronic population between the different subbands, as well as the dependence of these magnitudes with the density of impurities in the layer. The participation of the bans of heavy holes is analysed, light and split-off band in the total electronic population. The effect of the temperature is discussed and we give a possible qualitative explanation of the experimental optical properties. (Author)

  1. Stable Isotope (delta OXYGEN-18, Delta Deuterium, Delta CARBON-13) Dendroclimatological Studies in the Waterloo Region of Southern Ontario, Canada, Between AD 1610 and 1990.

    Science.gov (United States)

    Buhay, William Mark

    Oxygen (delta^{18} O), hydrogen (delta^2H) and carbon (delta^{13}C) isotopes were measured in wood cellulose from elm, white pine and maple trees that grew in southwestern Ontario, Canada. The measured oxygen and hydrogen isotopic data were used for model-based reconstructions of delta^{18}{O}_{meteoric water}, mean annual temperature (MAT) and relative humidity for a period, AD 1610 to 1880, that precedes instrumental records of climate. The carbon isotope measurements were compared with the Cellulose Model inferred climate data to reveal additional environmental information. Modifications made to the Cellulose Model focused on the dynamics of oxygen and hydrogen isotopic fractionation in plants during evapotranspiration and photosynthetic assimilation. For instance, kinetic fractionation of ^{18}O was found to be predictable from theoretical considerations of leaf energy balance and boundary layer dynamics. Kinetic fractionation during evapotranspiration is sensitive to the nature of the boundary layer, which is controlled by leaf size and morphology. Generally, plants with small segmented leaves have a lower component of turbidity in the leaf boundary layer, which results in higher kinetic fractionation values, than do plants having large simple leaves and more turbulent boundary layers. Kinetic ^2H enrichment in plant leaf water can also be rationalized in terms of leaf size and morphology when an apparent temperature-dependent isotope effect, acting in opposition to evaporative enrichment, is taken into account. Accounting for this temperature -dependent isotope effect helps to: (1) reconcile hydrogen kinetic fractionation inconsistencies for different leaves; (2) explain a temperature effect previously attributed to variable biochemical fractionation during cellulose synthesis, and; (3) verify hydrogen biochemical effects in plants. This improved characterization of the oxygen and hydrogen isotopic effects in plants, using the modified Cellulose Model, helped

  2. Tracking the Flow of Resources in Electronic Waste - The Case of End-of-Life Computer Hard Disk Drives.

    Science.gov (United States)

    Habib, Komal; Parajuly, Keshav; Wenzel, Henrik

    2015-10-20

    Recovery of resources, in particular, metals, from waste flows is widely seen as a prioritized option to reduce their potential supply constraints in the future. The current waste electrical and electronic equipment (WEEE) treatment system is more focused on bulk metals, where the recycling rate of specialty metals, such as rare earths, is negligible compared to their increasing use in modern products, such as electronics. This study investigates the challenges in recovering these resources in the existing WEEE treatment system. It is illustrated by following the material flows of resources in a conventional WEEE treatment plant in Denmark. Computer hard disk drives (HDDs) containing neodymium-iron-boron (NdFeB) magnets were selected as the case product for this experiment. The resulting output fractions were tracked until their final treatment in order to estimate the recovery potential of rare earth elements (REEs) and other resources contained in HDDs. The results further show that out of the 244 kg of HDDs treated, 212 kg comprising mainly of aluminum and steel can be finally recovered from the metallurgic process. The results further demonstrate the complete loss of REEs in the existing shredding-based WEEE treatment processes. Dismantling and separate processing of NdFeB magnets from their end-use products can be a more preferred option over shredding. However, it remains a technological and logistic challenge for the existing system.

  3. Minority rights and resource-conflict in the poetry of Ibiwari Ikiriko ...

    African Journals Online (AJOL)

    Minority rights appear to be more contentious wherever resource-distribution is contested. Oil and Power are linked inextricably in the poetry that Ibiwari Ikiriko, Nnimmo Bassey and Ogaga Ifowodo have written on the Niger Delta mosaic. Power determines control and dispossession. Thus, these poets have depicted the ...

  4. Metallicism and pulsation: an analysis of the delta Delphini stars

    International Nuclear Information System (INIS)

    Kurtz, D.W.

    1976-01-01

    Fine abundance analyses of seven delta Delphini stars and one delta Scuti star relative to four comparison standards are presented. Five of the delta Del stars are shown to have abundances most similar to the evolved Am stars. It is argued that these abundances are different from the classical Am star and Ap star abundances and that similarities to the Ba II star abundances are coincidental. We suggest that the anomalous abundance delta Del stars are evolved metallic line stars on the basis of their abundances, position in the β, M/sub v/ plane, inferred rotational velocities, and perhaps their binary incidence. Some of the delta Del stars are delta Scuti pulsators. We argue that pulsation and metallicism are mutually exclusive among the classical Am stars but may coexist in other stars related to the classical Am stars. A preference for the diffusion hypothesis model for the metallic line stars is stated and supported and the implications of the coexistence of pulsation and diffusion are discussed

  5. Using remote sensing to monitor past changes and assess future scenarios for the Sacramento-San Joaquin River Delta waterways, California USA

    Science.gov (United States)

    Santos, Maria J.; Hestir, Erin; Khanna, Shruti; Ustin, Susan L.

    2017-04-01

    Historically, deltas have been extensively affected both by natural processes and human intervention. Thus, understanding drivers, predicting impacts and optimizing solutions to delta problems requires a holistic approach spanning many sectors, disciplines and fields of expertise. Deltas are ideal model systems to understand the effects of the interaction between social and ecological domains, as they face unprecedented disturbances and threats to their biological and ecological sustainability. The challenge for deltas is to meet the goals of supporting biodiversity and ecosystem processes while also provisioning fresh water resources for human use. We provide an overview of the last 150 years of the Sacramento-San Joaquin River delta, where we illustrate the parallel process of an increase in disturbances, by particularly zooming in on the current cascading effects of invasive species on geophysical and biological processes. Using remote sensing data coupled with in situ measurements of water quality, turbidity, and species presence we show how the spread and persistence of aquatic invasive species affects sedimentation processes and ecosystem functioning. Our results show that the interactions between the biological and physical conditions in the Delta affect the trajectory of dominance by native and invasive aquatic plant species. Trends in growth and community characteristics associated with predicted impacts of climate change (sea level rise, warmer temperatures, changes in the hydrograph with high winter and low summer outflows) do not provide simple predictions. Individually, the impact of specific environmental changes on the biological components can be predicted, however it is the complex interactions of biological communities with the suite of physical changes that make predictions uncertain. Systematic monitoring is critical to provide the data needed to document and understand change of these delta systems, and to identify successful adaptation

  6. Reactions of small negative ions with O2(a 1[Delta]g) and O2(X 3[Sigma]g-)

    Science.gov (United States)

    Midey, Anthony; Dotan, Itzhak; Seeley, J. V.; Viggiano, A. A.

    2009-02-01

    The rate constants and product ion branching ratios were measured for the reactions of various small negative ions with O2(X 3[Sigma]g-) and O2(a 1[Delta]g) in a selected ion flow tube (SIFT). Only NH2- and CH3O- were found to react with O2(X) and both reactions were slow. CH3O- reacted by hydride transfer, both with and without electron detachment. NH2- formed both OH-, as observed previously, and O2-, the latter via endothermic charge transfer. A temperature study revealed a negative temperature dependence for the former channel and Arrhenius behavior for the endothermic channel, resulting in an overall rate constant with a minimum at 500 K. SF6-, SF4-, SO3- and CO3- were found to react with O2(a 1[Delta]g) with rate constants less than 10-11 cm3 s-1. NH2- reacted rapidly with O2(a 1[Delta]g) by charge transfer. The reactions of HO2- and SO2- proceeded moderately with competition between Penning detachment and charge transfer. SO2- produced a SO4- cluster product in 2% of reactions and HO2- produced O3- in 13% of the reactions. CH3O- proceeded essentially at the collision rate by hydride transfer, again both with and without electron detachment. These results show that charge transfer to O2(a 1[Delta]g) occurs readily if the there are no restrictions on the ion beyond the reaction thermodynamics. The SO2- and HO2- reactions with O2(a) are the only known reactions involving Penning detachment besides the reaction with O2- studied previously [R.S. Berry, Phys. Chem. Chem. Phys., 7 (2005) 289-290].

  7. Isotopic variations ({delta}{sup 13} C and {delta}{sup 18} O) in Siderastrea stellata (Cnidaria-Anthozoa), Itamaraca island, State of Pernambuco, Northeastern Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Valderez P.; Sial, Alcides N. [Pernambuco Univ., Recife, PE (Brazil). Dept. de Geologia. Lab. de Isotopos Estaveis; Mayeal, Elga M.; Exner, Marco Antonio [Pernambuco Univ., Recife, PE (Brazil). Dept. de Zoologia. Lab. de Macro e Megabentos

    1998-12-01

    Isotopic determinations for O and C were performed in coral skeletons collected in beach rocks from two localities (Orange and Catuama), Itamaraca Island, north littoral of the State of pernambuco, northeastern Brazil. Large variations of {delta}{sup 18} O and {delta}{sup 13} C in corals from both localities are found, the largest ones being observed at the Orange locality {delta}{sup 13} C in this locality varies from -0.8 to +1.8% PDB and {delta}{sup 1.8} O from -5.3 to -1.8% PDB, while at the Catuama locality, they vary from -1.8 to 0.1% PDB and -3.8 to -2.7% PDB, respectively. Large variations in {delta}{sup 18} O (up to 2.5%) coupled with weakly defined positive correlation between {delta}{sup 18} O and {delta}{sup 13} C, can be attributed to temperature variations as consequence of climatic perturbations. Temperature estimates, calculated from {delta}{sup 18} O values, assuming isotopic equilibrium with seawater, yield values between 24.9 deg C and 43.1 deg C at Orange, and from 28.4 deg C to 35 deg C at Catuama, all of them (expect one growth band from one sample) are high enough for the full development of the coral colony. Temperature average is 31.4 deg C at Orange, which is a little bit higher than that at Catuama, but both of them indicate thermal stress conditions. In all analyzed specimens, expect for one, at Orange, T increases was accompanied by decreasing in the organic activity, as suggested by corresponding negative {delta}{sup 13} C anomaly. Therefore, the observed bleaching is possibly related to thermal stress and the high T may be related to the El Nino-Southern Oscillation (ENSO) warning event. On the other hand, anthropogenic action at Orange, local of intense tourism throughout the year, coupled with high rate of sedimentation in the region, may contribute to the observed coral bleaching. (author)

  8. Mesquite Risk Mapping and Assessment in Tokar Delta-Eastern Sudan

    OpenAIRE

    Suliman, Mahgoub; NAWATA, Hiroshi; Hoshino, Buho; Karamalla, Abdelaziz

    2015-01-01

    Tokar Delta is a name given to a small delta of approximately 161,000 hectares situated in the southern area of the Red Sea in Eastern Sudan. Beginning of 1980, mesquite species (Prosopis chilensis & Prosopis juliflora) were introduced to Tokar area to be planted as a shelterbelt for the city Tokar, but after while; it spread out to the delta area and became an invasive plant to the agricultural lands and along Khor Barak banks. Nowadays mesquite covers more than half of the delta area, decre...

  9. (p,. pi. /sup -/) reaction and. delta. /sup + +/ components of nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Kisslinger, L S; Miller, G A [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics

    1975-12-08

    The use of the (p,..pi../sup -/) reaction as a probe to determine ..delta../sup + +/(1232) components of nuclear wave functions is examined within the framework of a model which treats baryon resonances on the same footing as nucleons. Nuclear structure properties which affect the ..delta..-probability are discussed. Estimates of cross sections, at several energies, are made for the ..delta../sup + +/ transfer contribution as well as for the competing processes: proton charge exchange (p,n) followed by an (n,..gamma../sup -/) reaction; emission of a ..pi../sup 0/ followed by pion charge exchange (..pi../sup -/,..pi../sup 0/). Even with ..delta..-probabilities as small as 0.0001 the ..delta..-transfer process can compete with ordinary background charge-exchange reactions.

  10. How landscape scale changes affect ecological processes in conservation areas: external factors influence land use by zebra (Equus burchelli) in the Okavango Delta.

    Science.gov (United States)

    Bartlam-Brooks, Hattie L A; Bonyongo, Mpaphi C; Harris, Stephen

    2013-09-01

    Most large-bodied wildlife populations in sub-Saharan Africa only survive in conservation areas, but are continuing to decline because external changes influence ecological processes within reserves, leading to a lack of functionality. However, failure to understand how landscape scale changes influence ecological processes limits our ability to manage protected areas. We used GPS movement data to calculate dry season home ranges for 14 zebra mares in the Okavango Delta and investigated the effects of a range of landscape characteristics (number of habitat patches, mean patch shape, mean index of juxtaposition, and interspersion) on home range size. Resource utilization functions (RUF) were calculated to investigate how specific landscape characteristics affected space use. Space use by all zebra was clustered. In the wetter (Central) parts of the Delta home range size was negatively correlated with the density of habitat patches, more complex patch shapes, low juxtaposition of habitats and an increased availability of floodplain and grassland habitats. In the drier (Peripheral) parts of the Delta, higher use by zebra was also associated with a greater availability of floodplain and grassland habitats, but a lower density of patches and simpler patch shapes. The most important landscape characteristic was not consistent between zebra within the same area of the Delta, suggesting that no single foraging strategy is substantially superior to others, and so animals using different foraging strategies may all thrive. The distribution and complexity of habitat patches are crucial in determining space use by zebra. The extent and duration of seasonal flooding is the principal process affecting habitat patch characteristics in the Okavango Delta, particularly the availability of floodplains, which are the habitat at greatest risk from climate change and anthropogenic disturbance to the Okavango's catchment basin. Understanding how the factors that determine habitat

  11. Stark-like electron transfer between quantum wells

    International Nuclear Information System (INIS)

    Dubovis, S.A.; Voronko, A.N.; Basharov, A.M.

    2008-01-01

    The Stark-like mechanism of electron transfer between two energy subband localized in remote quantum wells is examined theoretically. Estimations of major parameters of the problem in case of delta-function-wells model are adduced. Schematic model allowing experimental study of Stark-like transfer is proposed

  12. The laser-based calibration system of delta spectrometer

    Energy Technology Data Exchange (ETDEWEB)

    Malakhov, A.I. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Anisimov, Yu.S. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Gmuca, S. [Inst. of Physics, SAS, Bratislava (Slovakia); Kizka, V.A. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Kliman, J. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Inst. of Physics, SAS, Bratislava (Slovakia); Krasnov, V.A. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Kurepin, A.B. [Inst. for Nuclear Research RAS, Moscow (Russian Federation); Kuznetsov, S.N. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Livanov, A.N. [Veksler and Baldin Laboratory of High Energies, JINR, Dubna (Russian Federation); Matousek, V. [Inst. of Physics, SAS, Bratislava (Slovakia); Morhac, M. [Inst. of Physics, SAS, Bratislava (Slovakia)]. E-mail: Miroslav.Morhac@savba.sk; Turzo, I. [Inst. of Physics, SAS, Bratislava (Slovakia)

    2006-10-15

    We present a report on a laser calibration system of DELTA spectrometer that has been designed and developed in the Laboratory of High Energies, JINR, Dubna. The system is intended for monitoring and continuous stabilization of the outputs of the detectors of the spectrometer. The UV nitrogen pulse laser along with optical filters, collection of optical fibers and plastic scintillators serving for conversion of UV light pulses to longer wavelength and for diffusion of the light beam to illuminate 300 photomultipliers are used. We stabilize the positions of laser peaks by corrections of high voltages of the corresponding photomultipliers. The proposed system allows one to accomplish the stabilization during the experiment with the use of the same electronics. The control software together with the first results from test runs are described as well.

  13. Polarized antiquark flavor asymmetry DELTA anti u(x)-DELTA anti d(x) and the pion cloud

    CERN Document Server

    Fries, R J; Weiss, C

    2003-01-01

    The flavor asymmetry of the unpolarized antiquark distributions in the proton, anti u(x)- anti d(x)0. Using a simple chiral linear sigma model as an example, we demonstrate that in the meson cloud picture a large positive DELTA anti u(x)-DELTA anti d(x) can be obtained from pi-sigma interference contributions. This calls into question previous estimates based on rho-meson contributions alone, and indicates how the results of the meson cloud picture may be reconciled with those of quark-based models. (orig.)

  14. Delta agent (Hepatitis D)

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000216.htm Hepatitis D (Delta agent) To use the sharing features on this page, please enable JavaScript. Hepatitis D is a viral infection caused by the ...

  15. Contaminant Effects on California Bay–Delta Species and Human Health

    Directory of Open Access Journals (Sweden)

    Stephanie Fong

    2016-12-01

    Full Text Available doi: https://doi.org/10.15447/sfews.2016v14iss4art5Many contaminants in the California Bay–Delta (Bay–Delta exceed regulatory standards, affect aquatic species, and potentially affect human health. Recent studies provide multiple lines of evidence that contaminants affect species of concern in the Bay–Delta (e.g., the decline of several important fish species referred to as the “Pelagic Organism Decline” or POD. Contaminants occur as dynamic complex mixtures and exert effects at multiple levels of biological organization. Multiple chemicals impair processes at cellular and physiological levels (measured as growth, development, and behavior abnormalities, and when viability and reproductive output are affected, populations are affected. As an important example, the population decline of the endangered Delta Smelt (Hypomesus transpacificus is significantly associated with multiple stressors, including insecticide use. New analyses presented in this paper show significant correlations between pyrethroid use and declining abundance of POD fish species. Water sampled from the Bay–Delta causes multiple deleterious effects in fish, and Delta Smelt collected from the Bay–Delta exhibit contaminant effects. Fish prey items are also affected by contaminants; this may have an indirect effect on their populations. Co-occurrence with thermal changes or disease can exacerbate contaminant effects. Contaminants also pose threats to human health via consumption of fish and shellfish, drinking water, and contact recreation, in particular, mercury, cyanobacteria toxins, disinfection byproducts, pathogens, pesticides, and pharmaceuticals and personal care products. The role of contaminants in the decline of Bay–Delta species is difficult to accurately assess in a complex, dynamic system. However, tools and approaches are available to evaluate contaminant effects on Bay–Delta species, and separate the effects of multiple stressors. Integrated

  16. Hepatitis delta in HIV-infected individuals in Europe

    DEFF Research Database (Denmark)

    Soriano, Vincent; Grint, Daniel; Monforte, Antonellad'arminio

    2011-01-01

    BACKGROUND:: Hepatitis delta virus (HDV) infection results in the most aggressive form of chronic viral hepatitis. There is scarce information about the prevalence, epidemiology, virological profile and natural historyof hepatitis delta in HIV patients. METHODS:: From 16,597 HIV patients enrolled......-RNA was quantified using a real-time PCR method. RESULTS:: A total of 61/422 HBsAg+ carriers were anti-HDV+ (prevalence: 14.5%). Hepatitis delta predominated in intravenous drug users and for this reason in South and/or East Europe. Serum HDV-RNA was detectable in 87% of tested anti-HDV+ patients, with a median...... titer of 1.76x10¿copies/ml. Overall, delta hepatitis patients showed lower serum HBV-DNA than the rest of HBsAg+ carriers, although the inhibitory effect of HDV on HBV replication was not recognized in HBV genotype D patients.Whereas HDV was not associated with progression to AIDS, it significantly...

  17. Within-canopy and ozone fumigation effects on delta13C and Delta18O in adult beech (Fagus sylvatica) trees: relation to meteorological and gas exchange parameters.

    Science.gov (United States)

    Gessler, Arthur; Löw, Markus; Heerdt, Christian; de Beeck, Maarten Op; Schumacher, Johannes; Grams, Thorsten E E; Bahnweg, Günther; Ceulemans, Reinhart; Werner, Herbert; Matyssek, Rainer; Rennenberg, Heinz; Haberer, Kristine

    2009-11-01

    In this study, the effects of different light intensities either in direct sunlight or in the shade crown of adult beech (Fagus sylvatica L.) trees on delta13C and Delta18O were determined under ambient (1 x O3) and twice-ambient (2 x O3) atmospheric ozone concentrations during two consecutive years (2003 and 2004). We analysed the isotopic composition in leaf bulk, leaf cellulose, phloem and xylem material and related the results to (a) meteorological data (air temperature, T and relative humidity, RH), (b) leaf gas exchange measurements (stomatal conductance, g(s); transpiration rate, E; and maximum photosynthetic activity, A(max)) and (c) the outcome of a steady-state evaporative enrichment model. Delta13C was significantly lower in the shade than in the sun crown in all plant materials, whilst Delta18O was increased significantly in the shade than in the sun crown in bulk material and cellulose. Elevated ozone had no effect on delta13C, although Delta18O was influenced by ozone to varied degrees during single months. We observed significant seasonal changes for both parameters, especially in 2004, and also significant differences between the study years. Relating the findings to meteorological data and gas exchange parameters, we conclude that the differences in Delta18O between the sun and the shade crown were predominantly caused by the Péclet effect. This assumption was supported by the modelled Delta18O values for leaf cellulose. It was demonstrated that independent of RH, light-dependent reduction of stomatal conductance (and thus transpiration) and of A(max) can drive the pattern of Delta18O increase with the concomitant decrease of delta13C in the shade crown. The effect of doubling ozone levels on time-integrated stomatal conductance and transpiration as indicated by the combined analysis of Delta18O and delta13C was much lower than the influence caused by the light exposure.

  18. The Niger Delta Crisis

    African Journals Online (AJOL)

    chifaou.amzat

    2013-09-28

    Sep 28, 2013 ... Department of History & International Studies, Delta State University, Abraka,. Nigeria. .... democracy implies popular power. That is ... Okonta (2006:5) draws attention to Anna Zalik's treatise called 'Petro-Vio- lence' and ...

  19. Phonon dispersion curves determination in (delta)-phase Pu-Ga alloys

    Energy Technology Data Exchange (ETDEWEB)

    Wong, J; Clatterbuck, D; Occelli, F; Farber, D; Schwartz, A; Wall, M; Boro, C; Krisch, M; Beraud, A; Chiang, T; Xu, R; Hong, H; Zschack, P; Tamura, N

    2006-02-07

    We have designed and successfully employed a novel microbeam on large grain sample concept to conduct high resolution inelastic x-ray scattering (HRIXS) experiments to map the full phonon dispersion curves of an fcc {delta}-phase Pu-Ga alloy. This approach obviates experimental difficulties with conventional inelastic neutron scattering due to the high absorption cross section of the common {sup 239}Pu isotope and the non-availability of large (mm size) single crystal materials for Pu and its alloys. A classical Born von-Karman force constant model was used to model the experimental results, and no less than 4th nearest neighbor interactions had to be included to account for the observation. Several unusual features including, a large elastic anisotropy, a small shear elastic modulus, (C{sub 11}-C{sub 12})/2, a Kohn-like anomaly in the T{sub 1}[011] branch, and a pronounced softening of the T[111] branch towards the L point in the Brillouin are found. These features may be related to the phase transitions of plutonium and to strong coupling between the crystal structure and the 5f valence instabilities. Our results represent the first full phonon dispersions ever obtained for any Pu-bearing material, thus ending a 40-year quest for this fundamental data. The phonon data also provide a critical test for theoretical treatments of highly correlated 5f electron systems as exemplified by recent dynamical mean field theory (DMFT) calculations for {delta}-plutonium. We also conducted thermal diffuse scattering experiments to study the T(111) dispersion at low temperatures with an attempt to gain insight into bending of the T(111) branch in relationship to the {delta} {yields} {alpha}{prime} transformation.

  20. Organic/metal interfaces. Electronic and structural properties

    Energy Technology Data Exchange (ETDEWEB)

    Duhm, Steffen

    2008-07-17

    This work addresses several important topics of the field of organic electronics. The focus lies on organic/metal interfaces, which exist in all organic electronic devices. Physical properties of such interfaces are crucial for device performance. Four main topics have been covered: (i) the impact of molecular orientation on the energy levels, (ii) energy level tuning with strong electron acceptors, (iii) the role of thermodynamic equilibrium at organic/ organic homo-interfaces and (iv) the correlation of interfacial electronic structure and bonding distance. To address these issues a broad experimental approach was necessary: mainly ultraviolet photoelectron spectroscopy was used, supported by X-ray photoelectron spectroscopy, metastable atom electron spectroscopy, X-ray diffraction and X-ray standing waves, to examine vacuum sublimed thin films of conjugated organic molecules (COMs) in ultrahigh vacuum. (i) A novel approach is presented to explain the phenomenon that the ionization energy in molecular assemblies is orientation dependent. It is demonstrated that this is due to a macroscopic impact of intramolecular dipoles on the ionization energy in molecular assemblies. Furthermore, the correlation of molecular orientation and conformation has been studied in detail for COMs on various substrates. (ii) A new approach was developed to tune hole injection barriers ({delta}{sub h}) at organic/metal interfaces by adsorbing a (sub-) monolayer of an organic electron acceptor on the metal electrode. Charge transfer from the metal to the acceptor leads to a chemisorbed layer, which reduces {delta}{sub h} to the COM overlayer. This concept was tested with three acceptors and a lowering of {delta}{sub h} of up to 1.2 eV could be observed. (iii) A transition from vacuum-level alignment to molecular level pinning at the homo-interface between a lying monolayer and standing multilayers of a COM was observed, which depended on the amount of a pre-deposited acceptor. The

  1. T gamma/delta lymphocytes in renal transplant recipients

    NARCIS (Netherlands)

    Raasveld, M. H.; Bloemena, E.; Surachno, S.; ten Berge, R. J.

    1992-01-01

    T gamma/delta lymphocytes are able to perform allospecific cytotoxicity and natural killer cytotoxicity in vitro. However, very little is known about their function in vivo. To investigate the possible involvement of T gamma/delta lymphocytes in the immune response to renal allografts, fine-needle

  2. An integrated assessment framework for land subsidence in delta cities

    Directory of Open Access Journals (Sweden)

    T. H. M. Bucx

    2015-11-01

    Full Text Available In many delta cities land subsidence exceeds absolute sea level rise up to a factor of ten by excessive groundwater extraction related to rapid urbanization and population growth. Without change, parts of Jakarta, Ho Chi Minh City, Bangkok and numerous other delta (and coastal cities will sink below sea level. Increased flooding and also other widespread impacts of land subsidence result already in damage of billions of dollars per year. In order to gain insight in the complex, multi-sectoral aspects of subsidence, to raise awareness and to support decision making on appropriate adaptation strategies and measures, an Integrated Assessment Framework (IAF for subsidence is introduced, illustrated by several (delta case studies. Based on that a list of 10 generic key issues and possible solutions is presented in order to further develop and support a (generic approach how to deal with subsidence in current and future subsidence-prone areas. For exchange of experiences and knowledge development.on subsidence in deltas the Delta Alliance, a knowledge network of deltas worldwide, can be supportive.

  3. Delta ferrite in the weld metal of reduced activation ferritic martensitic steel

    Energy Technology Data Exchange (ETDEWEB)

    Sam, Shiju, E-mail: shiju@ipr.res.in [Institute for Plasma Research, Gandhinagar, Gujarat 382 428 (India); Das, C.R.; Ramasubbu, V.; Albert, S.K.; Bhaduri, A.K.; Jayakumar, T. [Indira Gandhi Centre for Atomic Research, Kalpakkam 603 102 (India); Rajendra Kumar, E. [Institute for Plasma Research, Gandhinagar, Gujarat 382 428 (India)

    2014-12-15

    Formation of delta(δ)-ferrite in the weld metal, during autogenous bead-on-plate welding of Reduced Activation Ferritic Martensitic (RAFM) steel using Gas Tungsten Arc Welding (GTAW) process, has been studied. Composition of the alloy is such that delta-ferrite is not expected in the alloy; but examination of the weld metal revealed presence of delta-ferrite in the weld metal. Volume fraction of delta-ferrite is found to be higher in the weld interface than in the rest of the fusion zone. Decrease in the volume fraction of delta-ferrite, with an increase in preheat temperature or with an increase in heat input, is observed. Results indicate that the cooling rate experienced during welding affects the volume fraction of delta-ferrite retained in the weld metal and variation in the delta-ferrite content with cooling rate is explained with variation in the time that the weld metal spends in various temperature regimes in which delta-ferrite is stable for the alloy during its cooling from the liquid metal to the ambient temperature. This manuscript will discuss the effect of welding parameters on formation of delta-ferrite and its retention in the weld metal of RAFM steel.

  4. Average of delta: a new quality control tool for clinical laboratories.

    Science.gov (United States)

    Jones, Graham R D

    2016-01-01

    Average of normals is a tool used to control assay performance using the average of a series of results from patients' samples. Delta checking is a process of identifying errors in individual patient results by reviewing the difference from previous results of the same patient. This paper introduces a novel alternate approach, average of delta, which combines these concepts to use the average of a number of sequential delta values to identify changes in assay performance. Models for average of delta and average of normals were developed in a spreadsheet application. The model assessed the expected scatter of average of delta and average of normals functions and the effect of assay bias for different values of analytical imprecision and within- and between-subject biological variation and the number of samples included in the calculations. The final assessment was the number of patients' samples required to identify an added bias with 90% certainty. The model demonstrated that with larger numbers of delta values, the average of delta function was tighter (lower coefficient of variation). The optimal number of samples for bias detection with average of delta was likely to be between 5 and 20 for most settings and that average of delta outperformed average of normals when the within-subject biological variation was small relative to the between-subject variation. Average of delta provides a possible additional assay quality control tool which theoretical modelling predicts may be more valuable than average of normals for analytes where the group biological variation is wide compared with within-subject variation and where there is a high rate of repeat testing in the laboratory patient population. © The Author(s) 2015.

  5. Delta count-rate monitoring system

    International Nuclear Information System (INIS)

    Van Etten, D.; Olsen, W.A.

    1985-01-01

    A need for a more effective way to rapidly search for gamma-ray contamination over large areas led to the design and construction of a very sensitive gamma detection system. The delta count-rate monitoring system was installed in a four-wheel-drive van instrumented for environmental surveillance and accident response. The system consists of four main sections: (1) two scintillation detectors, (2) high-voltage power supply amplifier and single-channel analyzer, (3) delta count-rate monitor, and (4) count-rate meter and recorder. The van's 6.5-kW generator powers the standard nuclear instrument modular design system. The two detectors are mounted in the rear corners of the van and can be run singly or jointly. A solid-state bar-graph count-rate meter mounted on the dashboard can be read easily by both the driver and passenger. A solid-state strip chart recorder shows trends and provides a permanent record of the data. An audible alarm is sounded at the delta monitor and at the dashboard count-rate meter if a detected radiation level exceeds the set background level by a predetermined amount

  6. Carbon storage in the Mississippi River delta enhanced by environmental engineering

    Science.gov (United States)

    Shields, Michael R.; Bianchi, Thomas S.; Mohrig, David; Hutchings, Jack A.; Kenney, William F.; Kolker, Alexander S.; Curtis, Jason H.

    2017-11-01

    River deltas have contributed to atmospheric carbon regulation throughout Earth history, but functioning in the modern era has been impaired by reduced sediment loads, altered hydrologic regimes, increased global sea-level rise and accelerated subsidence. Delta restoration involves environmental engineering via river diversions, which utilize self-organizing processes to create prograding deltas. Here we analyse sediment cores from Wax Lake delta, a product of environmental engineering, to quantify the burial of organic carbon. We find that, despite relatively low concentrations of organic carbon measured in the cores (about 0.4%), the accumulation of about 3 T m-2 of sediment over the approximate 60 years of delta building resulted in the burial of a significant amount of organic carbon (16 kg m-2). This equates to an apparent organic carbon accumulation rate of 250 +/- 23 g m-2 yr-1, which implicitly includes losses by carbon emissions and erosion. Our estimated accumulation rate for Wax Lake delta is substantially greater than previous estimates based on the top metre of delta sediments and comparable to those of coastal mangrove and marsh habitats. The sedimentation of carbon at the Wax Lake delta demonstrates the capacity of engineered river diversions to enhance both coastal accretion and carbon burial.

  7. Photoreflectance study of InAs ultrathin layer embedded in Si-delta-doped GaAs/AlGaAs quantum wells

    International Nuclear Information System (INIS)

    Dhifallah, I.; Daoudi, M.; Bardaoui, A.; Eljani, B.; Ouerghi, A.; Chtourou, R.

    2011-01-01

    Photoreflectance and photoluminescence studies were performed to characterize InAs ultrathin layer embedded in Si-delta-doped GaAs/AlGaAs high electron mobility transistors. These structures were grown by Molecular Beam Epitaxy on (1 0 0) oriented GaAs substrates with different silicon-delta-doped layer densities. Interband energy transitions in the InAs ultrathin layer quantum well were observed below the GaAs band gap in the photoreflectance spectra, and assigned to electron-heavy-hole (E e-hh ) and electron-light-hole (E e-lh ) fundamental transitions. These transitions were shifted to lower energy with increasing silicon-δ-doping density. This effect is in good agreement with our theoretical results based on a self-consistent solution of the coupled Schroedinger and Poisson equations and was explained by increased escape of photogenerated carriers and enhanced Quantum Confined Stark Effect in the Si-delta-doped InAs/GaAs QW. In the photoreflectance spectra, not only the channel well interband energy transitions were observed, but also features associated with the GaAs and AlGaAs bulk layers located at about 1.427 and 1.8 eV, respectively. By analyzing the Franz-Keldysh Oscillations observed in the spectral characteristics of Si-δ-doped samples, we have determined the internal electric field introduced by ionized Si-δ-doped centers. We have observed an increase in the electric field in the InAs ultrathin layer with increasing silicon content. The results are explained in terms of doping dependent ionized impurities densities and surface charges. - Research highlights: → Studying HEMTs structures with different silicon doping content. → An increase of the electric field in the InAs layer with increasing Si content. → The interband energy transitions in the HEMTs structures have been obtained from PR. → Experimental and theoretical values of transitions energies were in good agreement.

  8. Integrating scientific knowledge into large-scale restoration programs: the CALFED Bay-Delta Program experience

    Science.gov (United States)

    Taylor, K.A.; Short, A.

    2009-01-01

    Integrating science into resource management activities is a goal of the CALFED Bay-Delta Program, a multi-agency effort to address water supply reliability, ecological condition, drinking water quality, and levees in the Sacramento-San Joaquin Delta of northern California. Under CALFED, many different strategies were used to integrate science, including interaction between the research and management communities, public dialogues about scientific work, and peer review. This paper explores ways science was (and was not) integrated into CALFED's management actions and decision systems through three narratives describing different patterns of scientific integration and application in CALFED. Though a collaborative process and certain organizational conditions may be necessary for developing new understandings of the system of interest, we find that those factors are not sufficient for translating that knowledge into management actions and decision systems. We suggest that the application of knowledge may be facilitated or hindered by (1) differences in the objectives, approaches, and cultures of scientists operating in the research community and those operating in the management community and (2) other factors external to the collaborative process and organization.

  9. Involvement of formate as an interspecies electron carrier in a syntrophic acetate-oxidizing anaerobic microorganism in coculture with methanogens.

    Science.gov (United States)

    Hattori, S; Luo, H; Shoun, H; Kamagata, Y

    2001-01-01

    To determine whether formate is involved in interspecies electron transfer between substrate-oxidizing bacteria and hydrogenotrophic microorganisms under anaerobic conditions, a syntrophic acetate-oxidizing bacterium Thermacetogenium phaeum strain PB was cocultured either with a formate /H2-utilizing methanogen strain TM (designated as PB/TM coculture), or an H2-utilizing methanogen strain deltaH (designated as PB/deltaH coculture). Acetate oxidation and subsequent methanogenesis in PB/TM coculture were found to be significantly faster than in PB/deltaH coculture. Formate dehydrogenase and hydrogenase were both detected in strains PB and TM. H2 partial pressures in the PB/TM coculture were kept lower (20 to 40 Pa) than those of the PB/deltaH coculture (40 to 60 Pa) during the exponential growth phase. Formate was also detected in both PB/TM and PB/deltaH cocultures, and the concentration of formate was maintained at a lower level in the PB/TM coculture (5 to 9 microM) than in the PB/deltaH coculture. Thermodynamic calculations revealed that the concentrations of both H2 and formate severely affect the syntrophic oxidation of acetate. These results strongly indicate that not only H2 but also formate may be involved in interspecies electron transfer.

  10. Challenges and Approaches in River Delta Planning - report on training workshop

    NARCIS (Netherlands)

    Wosten, J.H.M.; Douven, W.; Long Phi, H.; Fida Abdullah Khan, M.

    2012-01-01

    River delta’s, like the Mekong Delta (Vietnam), Ganges-Brahmaputra Delta (Bangladesh), Irrawady (Myanmar) and Ciliwung Delta (Indonesia) are developing rapidly and characterized by large-scale urbanization and industrialization processes. They are facing serious planning challenges related to issues

  11. Diet-tissue stable isotope (delta¹³C and delta¹⁵N) discrimination factors for multiple tissues from terrestrial reptiles (rock iguanas, Cyclura species)

    OpenAIRE

    Steinitz, Ronnie

    2015-01-01

    Trophic interactions can drive community structure; therefore, studying food webs is key in understanding ecological communities. Stable isotope analysis is a powerful tool for reconstructing foraging patterns. However, stable isotope discrimination factors (delta¹³C and delta¹⁵N) are needed to best use this tool. We determined the first delta¹³C and delta¹⁵N values for Rock Iguanas (Cyclura spp.) to better understand isotope fractionation patterns in reptiles and estimate wild reptile diets....

  12. Conflict resolution among Niger delta communities: A historical ...

    African Journals Online (AJOL)

    Conflict related issues have assumed endemic proportion in the Niger Delta. A proper assessment of the critical factors in motion must take cognizance of their historical underpinnings. Peaceful co-existence, the hallmark of conflict resolution, can be feasible in the Niger Delta, through sustainable dialogue. These, among

  13. Environmental Risk Profiling of the Volta Delta, Ghana

    Science.gov (United States)

    Nyarko, B. K.; Appeaning-Addo, K.; Amisigo, B.

    2017-12-01

    Volta Delta communities find it difficult to absorb or bear risk at different levels, because of the physical and economic impacts of environmental hazards. In this regards various agencies and organizations have in recent years launched initiatives to measure and identify risk areas with a set of indicators and indices. The theory underpinning this study is concepts of Modern Portfolio Theory (MPT). The Cox proportional hazards regression model will be used as the model for the risk profile. Finding the optimal level of environmental risk for activities in the Volta Delta considering the risk required, risk capacity and risk tolerance. Using data from different sources, an environmental risk profile was developed for the Volta Delta. The result indicates that risks are distributed across the Delta. However, areas that have government interventions, such as sea defense system and irrigation facilities have less threat. In addition wealthy areas do effectively reduce the threat of any form of disaster.

  14. Desenvolvimento da ferrita delta na solda e ZTA resultante de soldagem plasma pulsada em um aço inoxidável supermartensítico Delta-ferrite development in weld and HAZ produced by pulsed plasma arc welding in a supermartensitic stainless steel

    Directory of Open Access Journals (Sweden)

    Sérgio L. Henke

    2013-03-01

    Full Text Available A ferrita delta é considerada uma fase indesejável na microestrutura dos aços inoxidáveis martensíticos haja vista a mesma poder influenciar no desempenho da resistência à fadiga, tenacidade e corrosão sob-tensão. Sendo assim, o objetivo deste trabalho foi investigar o efeito da soldagem plasma pulsada sobre a distribuição e quantidade de ferrita delta em um aço inoxidável supermartensítico. Para tal foram obtidos cordões por meio de fusão superficial sobre uma amostra de aço inoxidável supermartensítico de alta liga utilizando corrente pulsada e convencional. Em seguida foi efetuada a caracterização microestrutural, em especial da ferrita delta, via análises metalográficas por meio de microscopia óptica e eletrônica de varredura . Os experimentos revelaram que, para o mesmo aporte térmico, a pulsação de corrente promoveu a formação de ferrita delta na forma de bandas ao longo do cordão de solda e redução significativa desta fase na ZTA quando comparada à soldagem convencional.The objective of this study was to investigate the effect of pulsed plasma welding on the distribution and amount of delta ferrite which is considered an undesirable phase in a supermartensitic stainless steel. For such weld beads have been obtained by melting the surface of a sample of a high-alloy supermartensitic stainless steel using pulsed and conventional current. Microstructural characterization, especially of delta ferrite, was performed by metallographic analysis by means of optical microscopy and scanning electron microscopy. The experiments showed that for the same heat input, pulsed current promoted the formation of delta ferrite in the form of bands along the weld bead and caused a significant reduction of this phase in HAZ as compared to conventional welding.

  15. Metabolites of the 1',2'-dimethylheptyl analogue of delta-8-tetrahydrocannabinol in the mouse and their identification by gas chromatography/mass spectrometry.

    Science.gov (United States)

    Harvey, D J; Brown, N K

    1990-10-01

    Metabolism of the 1,2-dimethylheptyl analogue of delta-8-tetrahydrocannabinol (delta-8-DMHP) was studied in vitro using mouse hepatic microsomes and in vivo in mouse liver. Metabolites were extracted with ethyl acetate, concentrated by chromatography on Sephadex LH-20 and examined by low-resolution mass spectrometry as trimethylsilyl (TMS), (2H9)TMS and methyl ester/TMS derivatives. Reduction of metabolites with lithium aluminium deuteride also provided structural information. The electron-impact-induced mass spectrum of the TMS derivative of DMHP differed from that of its unbranched side-chain analogues in that prominent ions were produced by fragmentation of the side-chain at the expense of the retro-Diels-Alder fragmentation that was prominent in the spectra of the latter compounds. This, however, was found to reduce the relative abundance of ions diagnostic of side-chain hydroxy substitution in the spectra of the metabolites. In vitro, the only significant metabolite was 11-hydroxy-delta-8-DMHP. This is in contrast with metabolism of the corresponding delta-8-tetrahydrocannabinol (delta-8-THC, n-C5-side-chain) where a number of other monohydroxy metabolites are produced. Fifteen metabolites were found in vivo, of which nine were identified. Mass spectral information was not sufficient to determine the position of one of the hydroxy groups in the other six metabolites. The major site of hydroxylation was at C-11 and the resulting hydroxy metabolite was oxidized to delta-8-DMHP-11-oic acid. In this respect metabolism paralleled that of delta-8-THC. Dihydroxylation of the double bond also occurred, presumably via the epoxide.(ABSTRACT TRUNCATED AT 250 WORDS)

  16. Biomass co-firing for Delta Electricity

    International Nuclear Information System (INIS)

    Anon

    2014-01-01

    Electricity generator Delta Electricity has implemented a biomass co-firing program at its Vales Point power station on the Central Coast to reduce its reliance on coal and emissions of CO 2 . The program comprises two parts: direct co-firing with coal of up to 5% biomass; and development of Continuous Biomass Converter (CBC) technology with the Crucible Group to remove technology constraints and enable much higher rates of biomass co-firing. It is talking industrial scale tests. Delta increased biomass co-firing in 2013/14 to 32,000 tonnes, up from just 3,000 tonnes the previous year, and conducted biochar co-firing trials at a rate equivalent to 400,000 tonnes per annum to demonstrate the potential of CBC technology. It reduced CO 2 emissions in 2013/14 by more than 32,000 tonnes. 'Legislation and regulations define biomass as renewable,' said Delta Electricity sustainability manager Justin Flood. 'By preferring biomass over coal, the carbon in the coal is not burnt and remains locked up.' One biomass source is wood waste that would normally go to landfill, but the primary driver of Delta's recent increase in co-firing is sawmill residues. 'Previously there was a higher value market for the residues for paper pulp. However, when that market evaporated the timber industry was left with a sizable problem in terms of what to do with its residues and the loss of revenue,' said Flood. The way greenhouse gas accounting is conducted in Australia, with carbon emissions based on site activities, makes it difficult to undertake a life cycle assessment of the program. 'However, some of the international studies looking at this issue have concluded that the net carbon emissions of the biomass system are significantly lower than the coal system because of the uptake of carbon during biomass growth,' said Flood. Delta identified two challenges, sourcing the feedstock and that biomass conversion to electricity is slightly less

  17. 78 FR 45592 - DeltaPoint Capital IV, LP;

    Science.gov (United States)

    2013-07-29

    ..., Suite 160, Pittsford, NY 14534. The financing was contemplated for working capital. The financing is... SMALL BUSINESS ADMINISTRATION [License No. 02/02-0662] DeltaPoint Capital IV, LP; Notice Seeking... given that DeltaPoint Capital IV, L.P., 45 East Avenue, 6th Floor, Rochester, NY 14604, Federal...

  18. Towards a Comprehensive Framework for Adaptive Delta Management

    NARCIS (Netherlands)

    Marchand, M.; Ludwig, F.

    2014-01-01

    Deltas are dynamic landforms at the boundary of land and sea, involving intricate mazes of rivers and small waterways, wetlands, estuaries and coastal barrier islands. They are home to over half a billion people. Deltas are also home to rich ecosystems, such as mangroves and marshes. They are

  19. Conservative Delta Hedging

    Science.gov (United States)

    1997-09-01

    an exact method for converting such intervals into arbitrage based prices of financial derivatives or industrial or contractual options. We call this...procedure conservative delta hedging . As existing procedures are of an ad hoc nature, the proposed approach will permit an institution’s man agement a greater oversight of its exposure to risk.

  20. Improving the Legal System Regime Specific to Biosphere Reservation of Danube Delta achieved by the Law no. 136 of July 5, 2011

    Directory of Open Access Journals (Sweden)

    Tache Bocaniala

    2012-08-01

    Full Text Available In order to establish a regime of protection and conservation of the Danube Delta, but alsoto achieve international commitments of Romania, it was developed and adopted by the Parliament aspecial law, Law no. 82/1993, establishing the Biosphere Reservation of Danube Delta. Theestablished rules had in mind mainly the preservation and protection of the existing natural heritage,promoting the sustainable use of resources resulting from natural ecosystems of the reserve andreconstruction of areas damaged by the impact of human activities. Although repeatedly amended andsupplemented, this regulatory framework has always been overwhelmed by economic and socialdevelopment of the area, requiring practically a major reform that was carried out by Law no 136 ofJuly 5, 2011.

  1. Sedimentation patterns in floodplains of the Mekong Delta - Vietnam

    Science.gov (United States)

    Van Manh, Nguyen; Merz, Bruno; Viet Dung, Nguyen; Apel, Heiko

    2013-04-01

    Quantification of floodplain sedimentation during the flood season in the Mekong Delta (MD) plays a very important role in the assessment of flood deposits for a sustainable agro-economic development. Recent studies on floodplain sedimentation in the region are restricted to small pilot sites because of the large extend of the Delta, and the complex channel. This research aims at a quantification of the sediment deposition in floodplains of the whole Mekong Delta, and to access the impacts of the upstream basin development on the sedimentation in the Delta quantitatively. To achieve this, a suspended sediment transport model is developed based on the quasi-2D hydrodynamic model of the whole Mekong Delta developed by Dung et al. (2011). The model is calibrated and validated using observed data derived from several sediment measurement campaigns in channel networks and floodplains. Measured sediment data and hydrodynamic model quantify the spatio-temporal variability of sediment depositions in different spatial units: individual dyke compartments, and the sub-regions Plain of Reeds, Long Xuyen Quadrangle and the area between Tien River and Hau River. It is shown that the distribution of sediment deposition over the delta is highly depended on the flood magnitude, that in turn drives the operation policy of flood control systems in floodplains of the Mekong Delta. Thus, the sedimentation distribution is influenced by the protection level of the dyke systems in place and the distance to the Tien River and Hau River, the main branches of the Mekong in the Delta. This corroborates the main findings derived from data analysis obtained from a small scale test site by Hung et al, (2011, 2012a). Moreover, the results obtained here underlines the importance of the main channels for the sediment transport into the floodplains, and the deposition rate in floodplains is strongly driven by the intake locations and the distance from these to the main channels as well.

  2. Flipped SU(5) predicts {delta}T/T

    Energy Technology Data Exchange (ETDEWEB)

    Kyae, Bumseok [School of Physics, Korea Institute for Advanced Study, 207-43, Cheongnyangni-Dong, Dongdaemun-Gu, Seoul 130-722 (Korea, Republic of)]. E-mail: bkyae@kias.re.kr; Shafi, Qaisar [Bartol Research Institute, Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)]. E-mail: shafi@bartol.udel.edu

    2006-04-20

    We discuss hybrid inflation in supersymmetric flipped SU(5) model such that the cosmic microwave anisotropy {delta}T/T is essentially proportional to (M/M{sub P}){sup 2}, where M denotes the symmetry breaking scale and M{sub P} (=2.4x10{sup 18} GeV) is the reduced Planck mass. The magnitude of M determined from {delta}T/T measurements can be consistent with the value inferred from the evolution of SU(3) and SU(2) gauge couplings. In other words, one could state that flipped SU(5) predicts (more precisely 'postdicts') {delta}T/T. The scalar spectral index n{sub s}=0.993+/-0.007, the scalar to tensor ratio satisfies r-bar 10{sup -6}, while dn{sub s}/dlnk-bar 4x10{sup -4}.

  3. What fish and how many there are in Danube Delta?

    Directory of Open Access Journals (Sweden)

    NĂVODARU Ion

    2011-09-01

    1972 and starting from 1972 until 2010, gibel carp become the dominant commercial species, followed by roach + rudd and bream + white bream. Since, fish estimation based on sampling gives valuable data on actual status of fish structure, catch statistics describe fish evolution and changes in time due to environmental pressure, both analyses are valuable tools in sustainable management of fish resources and for promoting conservation of fish diversity inDanube delta.

  4. Thermostatted delta f

    International Nuclear Information System (INIS)

    Krommes, J.A.

    2000-01-01

    The delta f simulation method is revisited. Statistical coarse-graining is used to rigorously derive the equation for the fluctuation delta f in the particle distribution. It is argued that completely collisionless simulation is incompatible with the achievement of true statistically steady states with nonzero turbulent fluxes because the variance of the particle weights w grows with time. To ensure such steady states, it is shown that for dynamically collisionless situations a generalized thermostat or W-stat may be used in lieu of a full collision operator to absorb the flow of entropy to unresolved fine scales in velocity space. The simplest W-stat can be implemented as a self-consistently determined, time-dependent damping applied to w. A precise kinematic analogy to thermostatted nonequilibrium molecular dynamics (NEMD) is pointed out, and the justification of W-stats for simulations of turbulence is discussed. An extrapolation procedure is proposed such that the long-time, steady-state, collisionless flux can be deduced from several short W-statted runs with large effective collisionality, and a numerical demonstration is given

  5. Effects of local and spatial conditions on the quality of harvested rainwater in the Mekong Delta, Vietnam

    International Nuclear Information System (INIS)

    Wilbers, Gert-Jan; Sebesvari, Zita; Rechenburg, Andrea; Renaud, Fabrice G.

    2013-01-01

    The objective of this study was to assess the quality of harvested rainwater in the Mekong Delta (MD), Vietnam for local (roof types, storage system and duration) and spatial (proximity of industry, main roads, coastline) conditions. 78 harvested rainwater samples were collected in the MD and analyzed for pH, turbidity, TDS, COD, nutrients (NH 4 , NO 3 , NO 2 , o-PO 4 ), trace metals and coliforms. The results show that thatch roofs lead to an increase of pollutants like COD (max 23.2 mgl −1 ) and turbidity (max 10.1 mgl −1 ) whereas galvanized roofs lead to an increase of Zn (max 2.2 mgl −1 ). The other local and spatial parameters had no or only minor influence on the quality of household harvested rainwater. However, lead (Pb) (max. 16.9 μgl −1 ) and total coliforms (max. 102 500 CFU100 ml −1 ) were recorded at high concentrations, probably due to a variety of household-specific conditions such as rainwater storage, collection and handling practices. -- Highlights: •Rainwater is a main drinking water source in the Mekong Delta. •Harvested rainwater is severely polluted for turbidity, lead and (total) coliforms. •Roof types significantly affect the quality of harvested rainwater. •Effects of household conditions on harvested rainwater quality should be further assessed. •Harvested rainwater is in potential a safe drinking water resource in the Mekong Delta. -- Concentrations of lead and total coliforms in household-harvested rainwater in the Mekong Delta exceed drinking water guidelines in 17% and 92% of the samples, respectively

  6. Lava delta deformation as a proxy for submarine slope instability

    Science.gov (United States)

    Di Traglia, Federico; Nolesini, Teresa; Solari, Lorenzo; Ciampalini, Andrea; Frodella, William; Steri, Damiano; Allotta, Benedetto; Rindi, Andrea; Marini, Lorenzo; Monni, Niccolò; Galardi, Emanuele; Casagli, Nicola

    2018-04-01

    The instability of lava deltas is a recurrent phenomenon affecting volcanic islands, which can potentially cause secondary events such as littoral explosions (due to interactions between hot lava and seawater) and tsunamis. It has been shown that Interferometric Synthetic Aperture Radar (InSAR) is a powerful technique to forecast the collapse of newly emplaced lava deltas. This work goes further, demonstrating that the monitoring of lava deltas is a successful strategy by which to observe the long-term deformation of subaerial-submarine landslide systems on unstable volcanic flanks. In this paper, displacement measurements derived from Synthetic Aperture Radar (SAR) imagery were used to detect lava delta instability at Stromboli volcano (Italy). Recent flank eruptions (2002-2003, 2007 and 2014) affected the Sciara del Fuoco (SdF) depression, created a "stacked" lava delta, which overlies a pre-existing scar produced by a submarine-subaerial tsunamigenic landslide that occurred on 30 December 2002. Space-borne X-band COSMO-SkyMED (CSK) and C-band SENTINEL-1A (SNT) SAR data collected between February 2010 and October 2016 were processed using the SqueeSAR algorithm. The obtained ground displacement maps revealed the differential ground motion of the lava delta in both CSK and SNT datasets, identifying a stable area (characterized by less than 2 mm/y in both datasets) within the northern sector of the SdF and an unstable area (characterized by velocity fields on the order of 30 mm/y and 160 mm/y in the CSK and SNT datasets, respectively) in the central sector of the SdF. The slope stability of the offshore part of the SdF, as reconstructed based on a recently performed multibeam bathymetric survey, was evaluated using a 3D Limit Equilibrium Method (LEM). In all the simulations, Factor of Safety (F) values between 0.9 and 1.1 always characterized the submarine slope between the coastline and -250 m a.s.l. The critical surfaces for all the search volumes corresponded to

  7. Parametrization of the. delta. residue function. [Complex functions

    Energy Technology Data Exchange (ETDEWEB)

    Vasan, S S [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics

    1976-04-19

    The complex residues at the ..delta..(1236) and ..delta..(1950) poles in the relevant partial-wave amplitudes provide information on the behaviour of the ..delta.. Regge residue function in the resonance region u>0. Attempts to incorporate this information in parametrizations of the residue by functions that are real on the real u-axis result in residues which have unsatisfactory behaviour in the region u<1GeV/sup 2/. The choice of complex functions for the trajectory and residue removes this undesirable feature and provides a better representation of the residue in the resonance region, suggesting that complex parametrizations would be better suited to Regge analyses of near-backward scattering.

  8. Beyond the Dams: Linking Rural Smallholder Soil and Water Management Practices in Tropical Deltas to Sea Level Rise Vulnerability

    Science.gov (United States)

    Rogers, K. G.; Syvitski, J. P.; Brondizio, E. S.

    2014-12-01

    The increased vulnerability of deltaic communities to coastal flooding as a result of upstream engineering has been acknowledged for decades. What has received less attention is the sensitivity of deltas to the interactions of river basin modifications and cultivation and irrigation in their coastal regions, particularly in tropical deltas. Embanking, tilling, and crop or stock choice all affect the movement of sediment and water on deltas. Combined with reduced river and sediment discharge, soil and water management practices in coastal areas may in fact exacerbate the risk of tidal flooding, erosion of arable land, and salinization of soils and groundwater associated with sea level rise. Thus exists a cruel irony to smallholder subsistence farmers whose priorities are food, water and economic security, rather than sustainability of the regional environment. Such issues challenge disciplinary approaches and require integrated social-biophysical models able to understand and diagnose these complex relationships. The complementary Institutional Analysis and Development and SocioEcological Systems frameworks are applied to the southwestern Bengal Delta (Bangladesh). The method helps to define the relevant social and physical units operating on the common pool of environmental resources, those of climate, water and sediment. The conceptual frameworks are designed to inform development of a nested geospatial analysis and a dynamic coupled model to identify the social-biophysical feedbacks associated with smallholder soil and water management practices, coastal dynamics, and climate vulnerability in rural Bangladesh. Our presentation will discuss components of the conceptual frameworks and will introduce a bi-directional pilot study designed for obtaining and disseminating information about environmental change to farmers in southwest Bangladesh with potential application to rural farming communities in other tropical deltas.

  9. Effect of ageing on optical and thermal properties of YBa{sub 2}Cu{sub 3}O{sub 7}-{delta}

    Energy Technology Data Exchange (ETDEWEB)

    Nikolic, P.M.; Vujatovic, S.S.; Savic, S.M.; Ristic, M.M. [Institute of Technical Sciences of SASA, Belgrade (Czechoslovakia); Paraskevopoulos, K.M.; Zorbas, K.T. [Aristotle Univ., Thessaloniki (Greece). Solid State Section; Nikolic, M.V.; Aleksic, O.S. [Belgrade Univ. (Czechoslovakia). Center for Multidisciplinary Studies

    2007-07-15

    Photoacoustic phase and amplitude spectra of YBa{sub 2}Cu{sub 3}O{sub 7}-{delta} samples synthesised 18 years ago were measured and numerically analysed. The value of thermal diffusivity obtained on the aged samples was lower than the values obtained for fresh samples. Far infrared spectra of YBa{sub 2}Cu{sub 3}O{sub 7}-{delta} samples synthesised 18 years ago were recorded and analysed enabling determination of reflectivity peak phonon frequencies present at room temperature. X-ray diffraction analysis and far infrared reflectivity measurements enabled determination of a slight change of the oxygen content with time. The YBa{sub 2}Cu{sub 3}O{sub 7}-{delta} samples synthesised 18 years ago still remained superconducting, which was confirmed by resistivity measurements of the samples between 50 K and room temperature where the critical temperature was reduced from 93 to 73 K. Atomic force microscopy, scanning electron microscopy and energy dispersive X-ray microanalytical measurements were also performed confirming the composition of the sample. (orig.)

  10. Asymptotic value of screening parameter as determined from the one-electron fragment of the kinetic energy or electrostatic potential at the nucleus

    Energy Technology Data Exchange (ETDEWEB)

    Teruya, Hirohide; Anno, Tosinobu

    1985-09-01

    Numerical value of lim sub(Z ..-->.. infinity) delta(i, j)/delta Zsub(i), where (i, j) stands for average interaction energy of a pair of electrons embedded in hydrogenic orbitals (HAO's) is presented for a wide range of HAO's. Data to be presented should be useful to calculate the asymptotic limit of screening effect seen by an electron embedded in a given kind of orbital for an isoelectronic series of atoms as determined from the ''one-electron component'' of the total kinetic energy of or of the electrostatic potential at the nucleus within an atom.

  11. Central Delta languages: An overview | Kari | Stellenbosch Papers ...

    African Journals Online (AJOL)

    This paper presents an overview of the phonology, morphology and syntax of Central Delta languages. It also provides information on the geo-linguistic, demographic and sociolinguistic situation of these languages. It notes that Central Delta languages have a 20-vowel system, which divides into two sets of 10 vowels ...

  12. Topological Mappings via B&delta;g-Closed Sets

    OpenAIRE

    Maruthamuthu, Raja; Narayanasamy, Seenivasagan; Otchanathevar, Ravi

    2018-01-01

    In this paper we introduce a new class of functions called  B&delta;g-continuous functions. We obtain several characterizations and some their properties. Also we investigate its relationship with other types of functions. Further we introduce and study a new class of functions namely B&delta;g-irresolute.

  13. Sand transport, shear stress, and the building of a delta

    Science.gov (United States)

    Wagner, W.; Miller, K. L.; Hiatt, M. R.; Mohrig, D. C.

    2017-12-01

    River deltas distribute sediment to the coastal sea through a complex branching network of channels; however, the routing and storage of this sediment in and through the delta is poorly understood. We present results from field studies of the sediment and water transport through the branching Wax Lake Delta on the coast of Louisiana. Two channels studied, Main Pass and East Pass, maintain a near-equal total partitioning of flow and sediment. However, East Pass is narrower and has higher river velocities, lower tidal velocity fluctuations, less alluvial bed cover, and more sediment flux per unit width than Main Pass. We connect these differences to small differences in the geometry of the two channels and feedbacks between these differences. We link trends in measured sediment deposits to both measured and modeled shear velocities in Wax Lake Delta's channels and open water `islands' to understand how hydrologic processes shaped the sedimentary architecture of the delta. These connections define the sediment transport and deposition regimes in the WLD. We extend the results herein to suggest that the relationships between the available sediment and shear stress determines the basic planform of the Wax Lake Delta and cross-sectional geometries of its channels.

  14. Delta phase plutonium and its alloys with III B elements: a microscopic study; Etude du plutonium en phase {delta} et de ses alliages avec les elements de la colonne IIIB

    Energy Technology Data Exchange (ETDEWEB)

    Bouchet, J

    2001-07-01

    The plutonium belongs to the actinides where it occupies a crucial place. In the actinide series the competition between the itinerant and local character of the f-electrons is responsible of its unique properties. The series can be divided into two sub-series: the light ({sub 90}Th-{sub 94}Pu) and the heavy ({sub 95}Am and beyond) actinides with very different characteristics. The volume behavior of the light actinides is very similar to the one found for the transitions metals with a parabolic decrease of the volume as a function of atomic number. This trend can be explained by the itinerant character of the 5 f electrons which participate to the chemical bonding, and thus the light actinides are considered to form a 5 f transition series. The density functional theory in the local-density approximation (LDA) gives a good description of the ground state of the light actinides in agreement with experiment and a simple Friedel model can explain the parabolic decrease of the volumes. As for heavy actinides, the pattern is reversed: 5 f electrons are localized. This picture places plutonium as the link between the two series, at the transition from delocalized to localized states. The density functional theory within the local density approximation is a very crude approximation for these systems where the on-site interaction between f electrons is strong enough to overcome the kinetic energy. Equilibrium properties for the {delta}-phase of Pu have been calculated. Taking into account strong electron correlations in the 5 f shell, we show how the equilibrium volume and the bulk modulus are improved in comparison to previous results using the local density approximation (LDA) or the generalized gradient approximation (GGA). In addition, an augmentation of the orbital moment is observed due to the respect of Hund's rules, reducing the total magnetic moment. The stability of the {delta}-phase is explored and for the first time a positive value for the tetragonal shear

  15. Delta phase plutonium and its alloys with III B elements: a microscopic study; Etude du plutonium en phase {delta} et de ses alliages avec les elements de la colonne IIIB

    Energy Technology Data Exchange (ETDEWEB)

    Bouchet, J

    2001-07-01

    The plutonium belongs to the actinides where it occupies a crucial place. In the actinide series the competition between the itinerant and local character of the f-electrons is responsible of its unique properties. The series can be divided into two sub-series: the light ({sub 90}Th-{sub 94}Pu) and the heavy ({sub 95}Am and beyond) actinides with very different characteristics. The volume behavior of the light actinides is very similar to the one found for the transitions metals with a parabolic decrease of the volume as a function of atomic number. This trend can be explained by the itinerant character of the 5 f electrons which participate to the chemical bonding, and thus the light actinides are considered to form a 5 f transition series. The density functional theory in the local-density approximation (LDA) gives a good description of the ground state of the light actinides in agreement with experiment and a simple Friedel model can explain the parabolic decrease of the volumes. As for heavy actinides, the pattern is reversed: 5 f electrons are localized. This picture places plutonium as the link between the two series, at the transition from delocalized to localized states. The density functional theory within the local density approximation is a very crude approximation for these systems where the on-site interaction between f electrons is strong enough to overcome the kinetic energy. Equilibrium properties for the {delta}-phase of Pu have been calculated. Taking into account strong electron correlations in the 5 f shell, we show how the equilibrium volume and the bulk modulus are improved in comparison to previous results using the local density approximation (LDA) or the generalized gradient approximation (GGA). In addition, an augmentation of the orbital moment is observed due to the respect of Hund's rules, reducing the total magnetic moment. The stability of the {delta}-phase is explored and for the first time a positive value for the tetragonal

  16. Implementation of IMRT and VMAT using Delta4 phantom and portal dosimetry as dosimetry verification tools

    Energy Technology Data Exchange (ETDEWEB)

    Daci, Lulzime, E-mail: lulzime.daci@nodlandssykehuset.no [Nordland Hospital Trust, Bodø (Norway); Malkaj, Partizan, E-mail: malkaj-p@hotmail.com [Faculty of Mathematics Engineering and Physics Engineering, Polytechnic University of Tirana (Albania)

    2016-03-25

    In this study we analyzed and compared the dose distribution of different IMRT and VMAT plans with the intent to provide pre-treatment quality assurance using two different tools. Materials/Methods: We have used the electronic portal imaging device EPID after calibration to dose and correction for the background offset signal and also the Delta4 phantom after en evaluation of angular sensitivity. The Delta4 phantom has a two-dimensional array with ionization chambers. We analyzed three plans for each anatomical site calculated by Eclipse treatment planning system. The measurements were analyzed using γ-evaluation method with passing criteria 3% absolute dose and 3 mm distance to agreement (DTA). For all the plans the range of score has been from 97% to 99% for gantry fixed at 0° while for rotational planes there was a slightly decreased pass rates and above 95%. Point measurement with a ionization chamber were done in additional to see the accuracy of portal dosimetry and to evaluate the Delta4 device to various dose rates. Conclusions: Both Delt4 and Portal dosimetry shows good results between the measured and calculated doses. While Delta4 is more accurate in measurements EPID is more time efficient. We have decided to use both methods in the first steps of IMRT and VMAT implementation and later on to decide which of the tools to use depending on the complexity of plans, how much accurate we want to be and the time we have on the machine.

  17. Implementation of IMRT and VMAT using Delta4 phantom and portal dosimetry as dosimetry verification tools

    International Nuclear Information System (INIS)

    Daci, Lulzime; Malkaj, Partizan

    2016-01-01

    In this study we analyzed and compared the dose distribution of different IMRT and VMAT plans with the intent to provide pre-treatment quality assurance using two different tools. Materials/Methods: We have used the electronic portal imaging device EPID after calibration to dose and correction for the background offset signal and also the Delta4 phantom after en evaluation of angular sensitivity. The Delta4 phantom has a two-dimensional array with ionization chambers. We analyzed three plans for each anatomical site calculated by Eclipse treatment planning system. The measurements were analyzed using γ-evaluation method with passing criteria 3% absolute dose and 3 mm distance to agreement (DTA). For all the plans the range of score has been from 97% to 99% for gantry fixed at 0° while for rotational planes there was a slightly decreased pass rates and above 95%. Point measurement with a ionization chamber were done in additional to see the accuracy of portal dosimetry and to evaluate the Delta4 device to various dose rates. Conclusions: Both Delt4 and Portal dosimetry shows good results between the measured and calculated doses. While Delta4 is more accurate in measurements EPID is more time efficient. We have decided to use both methods in the first steps of IMRT and VMAT implementation and later on to decide which of the tools to use depending on the complexity of plans, how much accurate we want to be and the time we have on the machine.

  18. Using mobile electronic devices to deliver educational resources in developing countries.

    Science.gov (United States)

    Mazal, Jonathan Robert; Ludwig, Rebecca

    2015-01-01

    Developing countries have far fewer trained radiography professionals than developed countries, which exacerbates the limited access to imaging services. The lack of trained radiographers reflects, in part, limited availability of radiographer-specific educational resources. Historically, organizations that provided such resources in the developing world faced challenges related to the limited stock of current materials as well as expenses associated with shipping and delivery. Four mobile electronic devices (MEDs) were loaded with educational content (e-books, PDFs, and digital applications) spanning major radiography topics. The MEDs were distributed to 4 imaging departments in Ghana, India, Nepal, and Nigeria based on evidence of need for radiography-specific resources, as revealed by survey responses. A cost comparison of postal delivery vs digital delivery of educational content was performed. The effectiveness of delivering additional content via Wi-Fi transmission also was evaluated. Feedback was solicited on users' experience with the MEDs as a delivery tool for educational content. An initial average per e-book expense of $30.05, which included the cost of the device, was calculated for the MED delivery method compared with $15.56 for postal delivery of printed materials. The cost of the MED delivery method was reduced to an average of $10.05 for subsequent e-book deliveries. Additional content was successfully delivered via Wi-Fi transmission to all recipients during the 3-month follow-up period. Overall user feedback on the experience was positive, and ideas for enhancing the MED-based method were identified. Using MEDs to deliver radiography-specific educational content appears to be more cost effective than postal delivery of printed materials on a long-term basis. MEDs are more efficient for providing updates to educational materials. Customization of content to department needs, and using projector devices could enhance the usefulness of MEDs for

  19. A Novel Sigma-Delta Modulator with Fractional-Order Digital Loop Integrator

    Directory of Open Access Journals (Sweden)

    Chi Xu

    2017-01-01

    Full Text Available This paper proposes using a fractional-order digital loop integrator to improve the robust stability of Sigma-Delta modulator, thus extending the integer-order Sigma-Delta modulator to a non-integer-order (fractional-order one in the Sigma-Delta ADC design field. The proposed fractional-order Sigma-Delta modulator has reasonable noise characteristics, dynamic range, and bandwidth; moreover the signal-to-noise ratio (SNR is improved remarkably. In particular, a 2nd-order digital loop integrator and a digital PIλDμ controller are combined to work as the fractional-order digital loop integrator, which is realized using FPGA; this will reduce the ASIC analog circuit layout design and chip testing difficulties. The parameters of the proposed fractional-order Sigma-Delta modulator are tuned by using swarm intelligent algorithm, which offers opportunity to simplify the process of tuning parameters and further improve the noise performance. Simulation results are given and they demonstrate the efficiency of the proposed fractional-order Sigma-Delta modulator.

  20. Challenges and Approaches in River Delta Planning - Annexes to report on training workshop

    NARCIS (Netherlands)

    Wosten, J.H.M.; Douven, W.; Long Phi, H.; Fida Abdullah Khan, M.

    2012-01-01

    Programme, participants and all powerpoint presentations of the Delta Alliance Training Workshop: Challenges and approaches in river delta planning, sharing experiences from SE Asian Deltas and the Rhine-Meuse Delta. 22-26 October 2012, WACC, Vietnam National University, Ho Chi Minh City, Vietnam

  1. Cerebral correlates of delta waves during non-REM sleep revisited.

    Science.gov (United States)

    Dang-Vu, Thien Thanh; Desseilles, Martin; Laureys, Steven; Degueldre, Christian; Perrin, Fabien; Phillips, Christophe; Maquet, Pierre; Peigneux, Philippe

    2005-10-15

    We aimed at characterizing the neural correlates of delta activity during Non Rapid Eye Movement (NREM) sleep in non-sleep-deprived normal young adults, based on the statistical analysis of a positron emission tomography (PET) sleep data set. One hundred fifteen PET scans were obtained using H(2)(15)O under continuous polygraphic monitoring during stages 2-4 of NREM sleep. Correlations between regional cerebral blood flow (rCBF) and delta power (1.5-4 Hz) spectral density were analyzed using statistical parametric mapping (SPM2). Delta power values obtained at central scalp locations negatively correlated during NREM sleep with rCBF in the ventromedial prefrontal cortex, the basal forebrain, the striatum, the anterior insula, and the precuneus. These regions embrace the set of brain areas in which rCBF decreases during slow wave sleep (SWS) as compared to Rapid Eye Movement (REM) sleep and wakefulness (Maquet, P., Degueldre, C., Delfiore, G., Aerts, J., Peters, J.M., Luxen, A., Franck, G., 1997. Functional neuroanatomy of human slow wave sleep. J. Neurosci. 17, 2807-S2812), supporting the notion that delta activity is a valuable prominent feature of NREM sleep. A strong association was observed between rCBF in the ventromedial prefrontal regions and delta power, in agreement with electrophysiological studies. In contrast to the results of a previous PET study investigating the brain correlates of delta activity (Hofle, N., Paus, T., Reutens, D., Fiset, P., Gotman, J., Evans, A.C., Jones, B.E., 1997. Regional cerebral blood flow changes as a function of delta and spindle activity during slow wave sleep in humans. J. Neurosci. 17, 4800-4808), in which waking scans were mixed with NREM sleep scans, no correlation was found with thalamus activity. This latter result stresses the importance of an extra-thalamic delta rhythm among the synchronous NREM sleep oscillations. Consequently, this rCBF distribution might preferentially reflect a particular modulation of the

  2. Quantifying the importance of orbital over spin correlations in delta-Pu within density-functional theory

    International Nuclear Information System (INIS)

    Soderlind, P

    2008-01-01

    The electronic structure of plutonium is studied within the density-functional theory (DFT) model. Key features of the electronic structure are correctly modeled and bonding, total energy, and electron density of states are all consistent with measure data, although the prediction of magnetism is not consistent with many observations. Here we analyze the contributions to the electronic structure arising from spin polarization, orbital polarization, and spin-orbit interaction. These effects give rise to spin and orbital moments that are of nearly equal magnitude, but anti-parallel, suggesting a magnetic-moment cancellation with a zero total moment. Quantifying the spin versus orbital effects on the bonding, total energy, and electron spectra it becomes clear that the spin polarization is much less important than the orbital correlations. Consequently, a restricted DFT approach with a non-spin polarized electronic structure can produce reasonable equation-of-state and electron spectra for (delta)-Pu when the orbital effects are accounted for. Hence, we present two non-magnetic models. One in which the spin moment is canceled by the orbital moment and another in which the spin moment (and therefore the orbital moment) is restricted to zero

  3. Adaptive delta management: a comparison between the Netherlands and Bangladesh Delta Program

    NARCIS (Netherlands)

    Zevenbergen, Chris; Khan, Shah Alam; Alphen, van Jos; Terwisscha van Scheltinga, Catharien; Veerbeek, William

    2018-01-01

    In the Netherlands, the central government, water authorities, provinces and municipalities are working together on a new Delta Program on Flood Risk Management and Fresh Water Supply (DP). Its primary goal is to protect the Netherlands against floods and ensure the availability of fresh water, now

  4. Cohesive Sedimentary Processes on River-Dominated Deltas: New Perspectives from the Mississippi River Delta Front, Gulf of Mexico

    Science.gov (United States)

    Bentley, S. J.; Keller, G. P.; Obelcz, J.; Maloney, J. M.; Xu, K.; Georgiou, I. Y.; Miner, M. D.

    2016-12-01

    On river deltas dominated by proximal sediment accumulation (Mississippi, Huang He, others), the delta front region is commonly dominated by rapid accumulation of cohesive fluvial sediments, and mass-wasting processes that remobilize recently deposited sediments. Mass transport is preconditioned in sediments by high water content, biogenic gas production, over steepening, and is commonly triggered by strong wave loading and other processes. This understanding is based on extensive field studies in the 1970's and 80's. Recent studies of the Mississippi River Delta Front are yielding new perspectives on these processes, in a time of anthropogenically reduced sediment loads, rising sea level, and catastrophic deltaic land loss. We have synthesized many industry data sets collected since ca. 1980, and conducted new pilot field and modeling studies of sedimentary and morphodynamic processes. These efforts have yielded several key findings that diverge from historical understanding of this dynamic setting. First, delta distributary mouths have ceased seaward progradation, ending patterns that have been documented since the 18th century. Second, despite reduced sediment supply, offshore mass transport continues, yielding vertical displacements at rates of 1 m/y. This displacement is apparently forced by wave loading from storm events of near-annual return period, rather than major hurricanes that have been the focus of most previous studies. Third, core analysis indicates that this vertical displacement is occurring along failure planes >3 m in the seabed, rather than in more recently deposited sediments closer to the sediment-water interface. These seabed morphodynamics have the potential to destabilize both nearshore navigation infrastructure, and seabed hydrocarbon infrastructure offshore. As well, these findings raise more questions regarding the future seabed evolution offshore of major river deltas, in response to anthropogenic and climatic forcing.

  5. Success criteria for electronic medical record implementations in low-resource settings: a systematic review.

    Science.gov (United States)

    Fritz, Fleur; Tilahun, Binyam; Dugas, Martin

    2015-03-01

    Electronic medical record (EMR) systems have the potential of supporting clinical work by providing the right information at the right time to the right people and thus make efficient use of resources. This is especially important in low-resource settings where reliable data are also needed to support public health and local supporting organizations. In this systematic literature review, our objectives are to identify and collect literature about success criteria of EMR implementations in low-resource settings and to summarize them into recommendations. Our search strategy relied on PubMed queries and manual bibliography reviews. Studies were included if EMR implementations in low-resource settings were described. The extracted success criteria and measurements were summarized into 7 categories: ethical, financial, functionality, organizational, political, technical, and training. We collected 381 success criteria with 229 measurements from 47 articles out of 223 articles. Most papers were evaluations or lessons learned from African countries, published from 1999 to 2013. Almost half of the EMR systems served a specific disease area like human immunodeficiency virus (HIV). The majority of criteria that were reported dealt with the functionality, followed by organizational issues, and technical infrastructures. Sufficient training and skilled personnel were mentioned in roughly 10%. Political, ethical, and financial considerations did not play a predominant role. More evaluations based on reliable frameworks are needed. Highly reliable data handling methods, human resources and effective project management, as well as technical architecture and infrastructure are all key factors for successful EMR implementation. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Relationship between symmetry of porphyrinic pi-conjugated systems and singlet oxygen (1Delta g) yields: low-symmetry tetraazaporphyrin derivatives.

    Science.gov (United States)

    Ishii, Kazuyuki; Itoya, Hatsumi; Miwa, Hideya; Fujitsuka, Mamoru; Ito, Osamu; Kobayashi, Nagao

    2005-07-07

    We have investigated the excited-state properties and singlet oxygen ((1)Delta(g)) generation mechanism in phthalocyanines (4M; M = H(2), Mg, or Zn) and in low-symmetry metal-free, magnesium, and zinc tetraazaporphyrins (TAPs), that is, monobenzo-substituted (1M), adjacently dibenzo-substituted (2AdM), oppositely dibenzo-substituted (2OpM), and tribenzo-substituted (3M) TAP derivatives, whose pi conjugated systems were altered by fusing benzo rings. The S(1)(x) and S(1)(y) states (these lowest excited singlet states are degenerate in D(4)(h) symmetry) split in the low-symmetry TAP derivatives. The excited-state energies were quantitatively determined from the electronic absorption spectra. The lowest excited triplet (T(1)(x)) energies were also determined from phosphorescence spectra, while the second lowest excited triplet (T(1)(y)) states were evaluated by using the energy splitting between the T(1)(x) and T(1)(y) states previously reported (Miwa, H.; Ishii, K.; Kobayashi, N. Chem. Eur. J. 2004, 10, 4422-4435). The singlet oxygen quantum yields (Phi(Delta)) are strongly dependent on the pi conjugated system. In particular, while the Phi(Delta) value of 2AdH(2) is smallest in our system, that of 2OpH(2), an isomer of 2AdH(2), is larger than that of 4Zn, in contrast to the heavy atom effect. The relationship between the molecular structure and Phi(Delta) values can be transformed into a relationship between the S(1)(x) --> T(1)(y) intersystem crossing rate constant (k(ISC)) and the energy difference between the S(1)(x) and T(1)(y) states (DeltaE(S)(x)(T)(y)). In each of the Zn, Mg, and metal-free compounds, the Phi(Delta)/tau(F) values (tau(F): fluorescence lifetime), which are related to the k(ISC) values, are proportional to exp(-DeltaE(S)(x)(T)(y)), indicating that singlet oxygen ((1)Delta(g)) is produced via the T(1)(y) state and that the S(1)(x) --> T(1)(y) ISC process follows the energy-gap law. From the viewpoint of photodynamic therapy, our methodology

  7. Grain-size sorting in grainflows at the lee side of deltas

    NARCIS (Netherlands)

    Kleinhans, M.G.

    2005-01-01

    The sorting of sediment mixtures at the lee slope of deltas (at the angle of repose) is studied with experiments in a narrow, deep flume with subaqueous Gilbert-type deltas using varied flow conditions and different sediment mixtures. Sediment deposition and sorting on the lee slope of the delta

  8. Governance of ‘long term delta planning’ in Bangladesh, Vietnam and the Netherlands

    NARCIS (Netherlands)

    Staveren, van M.F.

    2014-01-01

    The Deltas in Times of Climate Change Conference II, taking place in September 2014, Rotterdam, presented a suitable occasion to discuss both delta challenges and interesting approaches to how ‘delta dynamics’ are being dealt with worldwide.1 Delta dynamics include here both environmental (including

  9. Structure of the [delta]-opioid receptor bound to naltrindole

    Energy Technology Data Exchange (ETDEWEB)

    Granier, Sébastien; Manglik, Aashish; Kruse, Andrew C.; Kobilka, Tong Sun; Thian, Foon Sun; Weis, William I.; Kobilka, Brian K. (Stanford-MED)

    2012-07-11

    The opioid receptor family comprises three members, the {mu}-, {delta}- and {kappa}-opioid receptors, which respond to classical opioid alkaloids such as morphine and heroin as well as to endogenous peptide ligands like endorphins. They belong to the G-protein-coupled receptor (GPCR) superfamily, and are excellent therapeutic targets for pain control. The {delta}-opioid receptor ({delta}-OR) has a role in analgesia, as well as in other neurological functions that remain poorly understood. The structures of the {mu}-OR and {kappa}-OR have recently been solved. Here we report the crystal structure of the mouse {delta}-OR, bound to the subtype-selective antagonist naltrindole. Together with the structures of the {mu}-OR and {kappa}-OR, the {delta}-OR structure provides insights into conserved elements of opioid ligand recognition while also revealing structural features associated with ligand-subtype selectivity. The binding pocket of opioid receptors can be divided into two distinct regions. Whereas the lower part of this pocket is highly conserved among opioid receptors, the upper part contains divergent residues that confer subtype selectivity. This provides a structural explanation and validation for the 'message-address' model of opioid receptor pharmacology, in which distinct 'message' (efficacy) and 'address' (selectivity) determinants are contained within a single ligand. Comparison of the address region of the {delta}-OR with other GPCRs reveals that this structural organization may be a more general phenomenon, extending to other GPCR families as well.

  10. T-cell receptor gamma delta bearing cells in normal human skin

    NARCIS (Netherlands)

    Bos, J. D.; Teunissen, M. B.; Cairo, I.; Krieg, S. R.; Kapsenberg, M. L.; Das, P. K.; Borst, J.

    1990-01-01

    T-cell antigen receptors (TCR) are divided into common alpha beta and less common gamma delta types. In the murine skin, TCR gamma delta+ cells have been reported to form the great majority of epidermal T lymphocytes. We have examined the relative contribution of TCR alpha beta+ and TCR gamma delta+

  11. Ecological investigation of Alaskan resource development

    International Nuclear Information System (INIS)

    Hanson, W.C.; Eberhardt, L.E.

    1980-01-01

    The objective is to provide an integrated program for the definition of ecological consequences of resource developments in northern Alaska. The qualitative and quantitative results obtained describe the environmental costs incurred by petroleum resource extraction and transportation, including interaction of wildlife populations with industrial activities. This section of the Annual Report presents information on impacted populations of arctic foxes, small mammals, and tundra-nesting birds in the Prudhoe Bay oil field and along the Trans-Alaska Pipeline and haul road; findings from similar studies from the Colville River Delta and other unimpacted habitats; field experiments to determine the sensitivity of lichen communities of the Brooks Range to sulfur dioxide concentrations likely to be encountered near pipeline pumping stations; and amounts of worldwide-fallout radionuclides in the lichen-caribou-Eskimo food chain

  12. Computational assessment of the electronic structures of cyclohexa-1,2,4-triene, 1-oxacyclohexa-2,3,5-triene (3delta(2)-pyran), their benzo derivatives, and cyclohexa-1,2-diene. An experimental approach to 3delta(2)-pyran.

    Science.gov (United States)

    Engels, Bernd; Schöneboom, Jan C; Münster, Arno F; Groetsch, Stefan; Christl, Manfred

    2002-01-16

    The six-membered cyclic allenes given in the title have been studied theoretically by means of an MR-CI approach. For all compounds, the allene structures were found to be the ground states in the gas phase. In the cases of cyclohexa-1,2-diene (1), the isobenzene 2, and the isonaphthalene 7, the most stable structures having a planar allene moiety are the diradicals 1b, 2b, and 7b, representing the transition states for the racemization of 1a, 2a, and 7a and being less stable than the latter by 14.1, 8.9, and 11.2 kcal/mol, respectively. At variance with this order, the 3delta(2)-pyran 4 and the chromene 5 have the zwitterions 4c and 5c as the most stable planar structures, which lie only 1.0 and 5.4 kcal/mol above 4a and 5a, respectively. According to the simulation of the solvent effect, 4c even becomes the ground state of 4 in THF solution. The frontier orbitals of the respective states of 2 and 4 suggest different rates and sites for the reaction with nucleophiles. For the first time, the pyran 4 has been generated and trapped. As a precursor for 4, 3-bromo-4H-pyran (9) was chosen, the synthesis of which was achieved on two routes from 4H-pyran. The treatment of 9 with potassium tert-butoxide (KOt-Bu)/18-crown-6 gave 4-tert-butoxy-4H-pyran as the only discernible product, whether styrene or furan was present, indicating the interception of 4 by KOt-Bu. Finally, the disagreement between the experiment and the theory concerning the heat of formation and the electronic nature of the isobenzene 2 is resolved by demonstrating that the experimental data can provide only an upper limit of the DeltaH(f) degrees value.

  13. Monitoring and modeling the fate of commonly used pesticides in surface water of the Lower Mekong Delta

    Science.gov (United States)

    van Toan, Pham; Sebesvari, Zita; Loan, Vo Phuong Hong; Renaud, Fabrice

    2010-05-01

    Introduction: The Lower Mekong Delta, one of the largest agricultural areas in Southeast Asia, has been reported to be increasingly polluted by agrochemicals since the beginning of the transformation processes in Vietnamese economy and specifically in the agricultural sector in 1986 (MRCS, 2007; Dasgupta et al., 2005; Dung, 2003; Phuong, 2003). Although pesticides have contributed significantly to enhancing agricultural productivity, these agrochemicals also have created risks to human health and environment (Margni, 2001; Phuong, 2003; Dasgupta et al., 2005) and lead to value loss of water resources (Phuong, 2003). While prohibited persistent organic pollutants such as HCHs and DDTs, were monitored and still detected in the Lower Mekong Delta in recent studies (Minh et al., 2007, Carvalho et al., 2008) little data exist on water pollution by recently used pesticides in the Delta. Aiming to fill this information gap, a study comprising three components was set up at two study sites of the Delta. Pesticide use and management was investigated through surveys and participatory rural appraisals with farmers; pesticide residue concentrations were determined in field outflows, connected irrigation canals and in drinking water and finally pesticide fate was predicted by using a coupled MIKE 11/ MIKE SHE model. This abstract focuses on the work done in the field of pesticide monitoring. The western study site (An Long Commune, Dong Thap province) represented an agricultural pattern with two intensive paddy rice crops per year and was heavily affected by flood in the rainy season. The second site located in the central part of the Delta (Ba Lang ward, Can Tho City) was characterized by a mix of paddy rice, vegetables and fruit trees. Fifteen pesticide compounds (buprofezin, butachlor, cypermethrin, difenozonazol, α-endosulfan, β-endosulfan, endosulfan-sulfate, fenobucarb, fipronil, hexaconazol, isoprothiolane, pretilachlor, profenofos, propanil, and propiconazol) were

  14. Linking rapid erosion of the Mekong River delta to human activities.

    Science.gov (United States)

    Anthony, Edward J; Brunier, Guillaume; Besset, Manon; Goichot, Marc; Dussouillez, Philippe; Nguyen, Van Lap

    2015-10-08

    As international concern for the survival of deltas grows, the Mekong River delta, the world's third largest delta, densely populated, considered as Southeast Asia's most important food basket, and rich in biodiversity at the world scale, is also increasingly affected by human activities and exposed to subsidence and coastal erosion. Several dams have been constructed upstream of the delta and many more are now planned. We quantify from high-resolution SPOT 5 satellite images large-scale shoreline erosion and land loss between 2003 and 2012 that now affect over 50% of the once strongly advancing >600 km-long delta shoreline. Erosion, with no identified change in the river's discharge and in wave and wind conditions over this recent period, is consistent with: (1) a reported significant decrease in coastal surface suspended sediment from the Mekong that may be linked to dam retention of its sediment, (2) large-scale commercial sand mining in the river and delta channels, and (3) subsidence due to groundwater extraction. Shoreline erosion is already responsible for displacement of coastal populations. It is an additional hazard to the integrity of this Asian mega delta now considered particularly vulnerable to accelerated subsidence and sea-level rise, and will be exacerbated by future hydropower dams.

  15. Detailed quantification of delta subsidence, compaction and interaction with man-made structures: the case of the NCA airport, France

    Science.gov (United States)

    Cavalié, O.; Sladen, A.; Kelner, M.

    2015-09-01

    River deltas are dynamic coastal systems and their evolutions are closely monitored as it often concentrates vital natural resources for the surrounding areas. Many deltas worldwide experience subsidence due to geological processes (sediment loading and compaction) or human activities (groundwater or hydrocarbon extraction, land reclamation). This causes shoreline erosion or wetland loss which represent serious issues for the population. In this study we investigate the dynamic of the Var delta (France) where reclaimed lands over sea have been built to host the Nice côte d'Azur airport (NCA). Actually, the stability of this infrastructure is a permanent concern since, in 1979, a newly built extension of the runway platform collapsed in the sea, causing important damages. The project of land extension stopped, but the present airport platform is still located on reclaimed land. Factors that can trigger such catastrophic landslide are thought to be linked to the delta activity and the artificial airport platform load. We used, therefore, Envisat InSAR data to measure accurately the ground deformation of the area that includes the Var delta and NCA airport. Combining data from ascending and descending orbits, we estimated the east-west and vertical components of the deformation and obtained very accurate displacement rate (with a 1σ error of 0.25 mm yr-1). We found that nearly all the deformation is vertical and impacts the whole Var delta. The Var valley subsides at a very low rate (0.5-1 mm yr-1) but downstream the subsidence rate increases and a clear jump is observed at the transition with the reclaimed lands (1-2 mm yr-1). On average, the reclaimed lands subside at 3 mm yr-1. Since the subsidence rate increases in correlation with the sediment thickness, we interpret it as the compaction of the delta quaternary sedimentary wedge. In addition, three areas subside faster (between 5 and 10 mm yr-1), with one calling for more attention as it is the largest and

  16. STUDY REGARDING TO AGGRESSIONS ON THE ECOSYSTEM DANUBE DELTA – BLACK SEA AND PROTECTIVE MEASURES

    Directory of Open Access Journals (Sweden)

    Ion Gr. IONESCU

    2014-06-01

    Full Text Available Danube Delta has suffered damages of habitat and species loss caused by factors, including: construction of dams upstream have degraded obviously flooding regime; creation of agricultural and fishing enclosures which decreased the natural and original surfaces; extending artificial navigation channels that negatively affected the hydrological regime and water quality of lakes; increase of nutrients in the water, industrial pollution and accumulate effluents that led to the reduction of plant and bird species; attempt to exploit quartz sand, very pure and fine, the sea levees, although they were protected as nature reserves because of the specific morphology and sub-Mediterranean vegetation covering them; tourism and illegal fishing; mismanagement of resources of reed and fish. The fact is that there was a slight improvement for the marine ecosystem, reported since the early 90s. At present, the area of the Danube Delta - Black Sea is developing sustainable, in terms of medium and economic perspective. In my study I used comparative methods, investigations, direct observations, measurements, calculations and actual data, obtained from surveys and direct observations, from prestigious, specialized and authorized institutions.

  17. Plant delta 15N correlates with the transpiration efficiency of nitrogen acquisition in tropical trees.

    Science.gov (United States)

    Cernusak, Lucas A; Winter, Klaus; Turner, Benjamin L

    2009-11-01

    Based upon considerations of a theoretical model of (15)N/(14)N fractionation during steady-state nitrate uptake from soil, we hypothesized that, for plants grown in a common soil environment, whole-plant delta(15)N (deltaP) should vary as a function of the transpiration efficiency of nitrogen acquisition (F(N)/v) and the difference between deltaP and root delta(15)N (deltaP - deltaR). We tested these hypotheses with measurements of several tropical tree and liana species. Consistent with theoretical expectations, both F(N)/v and deltaP - deltaR were significant sources of variation in deltaP, and the relationship between deltaP and F(N)/v differed between non-N(2)-fixing and N(2)-fixing species. We interpret the correlation between deltaP and F(N)/v as resulting from variation in mineral nitrogen efflux-to-influx ratios across plasma membranes of root cells. These results provide a simple explanation of variation in delta(15)N of terrestrial plants and have implications for understanding nitrogen cycling in ecosystems.

  18. Laboratory investigation on effects of flood intermittency on river delta dynamics

    Science.gov (United States)

    Miller, K. L.; Kim, W.

    2015-12-01

    In order to simplify the complex hydrological variability of flow conditions, experiments modeling delta evolution are often conducted using a representative "channel-forming" flood flow and then relate results to field settings using an intermittency factor, defined as the fraction of total time at flood conditions. Although this intermittency factor makes it easier to investigate how variables, such as relative base level and/or sediment supply, affect delta dynamics, little is known about how this generalization to a single flow condition affects delta processes. We conducted a set of laboratory experiments with periodic flow conditions to determine the effects of intermittent discharges on delta evolution. During the experiment, flood with a set water discharge and sediment supply, cycles between periods of normal flow where the water flux is halved and the sediment discharge is turned off. For each run, the magnitude of the flood is held constant, but the duration is assigned differently, thus varying the intermittency between 1 and 0.2. We find that as the intermittency factor decreases (duration of each flood period decreases), the delta topset has a larger, more elongated area with a shallower slope as a result of reworking on the delta topset during normal flow conditions. During periods of normal flow, the system adjusts towards a new equilibrium state that then in turn acts as the initial condition for the subsequent flood period. Furthermore, the natural delta avulsion cycle becomes obscured by the flood cycles as the flood duration becomes shorter than the autogenic behavior. These results suggest that the adjustment timescale for differing flow conditions is a factor in determining the overall shape of the delta and behavior of the fluviodeltaic channels. We conclude, periods of normal flow when topset sediment is reworked, may be just as important to delta dynamics as periods of flood when sediment is supplied to the system.

  19. Plasticity of gamma delta T cells: impact on the anti-tumor response

    Directory of Open Access Journals (Sweden)

    Virginie eLafont

    2014-12-01

    Full Text Available The tumor immune microenvironment contributes to tumor initiation, progression and response to therapy. Among the immune cell subsets that play a role in the tumor microenvironment, innate-like T cells that express T cell receptors composed of gamma and delta chains (gamma delta T cells are of particular interest. gamma delta T cells can contribute to the immune response against many tumor types (lymphoma, myeloma, melanoma, breast, colon, lung, ovary and prostate cancer directly through their cytotoxic activity and indirectly by stimulating or regulating the biological functions of other cell types required for the initiation and establishment of the anti-tumor immune response, such as dendritic cells and cytotoxic CD8+ T cells. However, the notion that tumor-infiltrating gamma delta T cells are a good prognostic marker in cancer was recently challenged by studies showing that the presence of these cells in the tumor microenvironment was associated with poor prognosis in both breast and colon cancer. These findings suggest that gamma delta T cells may also display pro-tumor activities. Indeed, breast tumor-infiltrating gamma deltaT cells could exert an immunosuppressive activity by negatively regulating DC maturation. Furthermore, recent studies demonstrated that signals from the microenvironment, particularly cytokines, can confer some plasticity to gamma delta T cells and promote their differentiation into gamma delta T cells with regulatory functions. This review focuses on the current knowledge on the functional plasticity of gamma delta T cells and its effect on their anti-tumor activities. It also discusses the putative mechanisms underlying gamma delta T cell expansion, differentiation and recruitment in the tumor microenvironment.

  20. Tight-binding electrons on triangular and kagome lattices under staggered modulated magnetic fields: quantum Hall effects and Hofstadter butterflies

    Energy Technology Data Exchange (ETDEWEB)

    Li Juan; Wang Yifei; Gong Changde, E-mail: yfwang_nju@hotmail.com [Center for Statistical and Theoretical Condensed Matter Physics, and Department of Physics, Zhejiang Normal University, Jinhua 321004 (China)

    2011-04-20

    We consider the tight-binding models of electrons on a two-dimensional triangular lattice and kagome lattice under staggered modulated magnetic fields. Such fields have two components: a uniform-flux part with strength {phi}, and a staggered-flux part with strength {Delta}{phi}. Various properties of the Hall conductances and Hofstadter butterflies are studied. When {phi} is fixed, variation of {Delta}{phi} leads to the quantum Hall transitions and Chern numbers of Landau subbands being redistributed between neighboring pairs. The energy spectra with nonzero {Delta}{phi}s have similar fractal structures but quite different energy gaps compared with the original Hofstadter butterflies of {Delta}{phi} = 0. Moreover, the fan-like structure of Landau levels in the low magnetic field region is also modified appreciably by {Delta}{phi}.

  1. Oil and Security in Nigeria: The Niger Delta Crisis | Owolabi | Africa ...

    African Journals Online (AJOL)

    This paper examines oil and security in Nigeria, with special reference to the crisis-ravaged Niger Delta. Its focus on the Niger Delta and its festering crisis stems from that region's critical importance to Nigeria. As the nation's treasure base, the Niger Delta provides over 80 percent of government revenues, 95 percent of ...

  2. In-vivo identification of direct electron transfer from Shewanella oneidensis MR-1 to electrodes via outer-membrane OmcA-MtrCAB protein complexes

    Energy Technology Data Exchange (ETDEWEB)

    Okamoto, Akihiro [Department of Applied Chemistry, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Nakamura, Ryuhei, E-mail: nakamura@light.t.u-tokyo.ac.jp [Department of Applied Chemistry, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Hashimoto, Kazuhito, E-mail: hashimoto@light.t.u-tokyo.ac.jp [Department of Applied Chemistry, School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); ERATO/JST, HASHIMOTO Light Energy Conversion Project (Japan)

    2011-06-30

    Graphical abstract: . Display Omitted Highlights: > Monolayer biofilm of Shewanella cells was prepared on an ITO electrode. > Extracellular electron transfer (EET) process was examined with series of mutants. > Direct ET was confirmed with outer-membrane-bound OmcA-MtrCAB complex. > The EET process was not prominently influenced by capsular polysaccharide. - Abstract: The direct electron-transfer (DET) property of Shewanella bacteria has not been resolved in detail due to the complexity of in vivo electrochemistry in whole-cell systems. Here, we report the in vivo assignment of the redox signal indicative of the DET property in biofilms of Shewanella oneidensis MR-1 by cyclic voltammetry (CV) with a series of mutants and a chemical marking technique. The CV measurements of monolayer biofilms formed by deletion mutants of c-type cytochromes ({Delta}mtrA, {Delta}mtrB, {Delta}mtrC/{Delta}omcA, and {Delta}cymA), and pilin ({Delta}pilD), capsular polysaccharide ({Delta}SO3177) and menaquinone ({Delta}menD) biosynthetic proteins demonstrated that the electrochemical redox signal with a midpoint potential at 50 mV (vs. SHE) was due to an outer-membrane-bound OmcA-MtrCAB protein complex of decaheme cytochromes, and did not involve either inner-membrane-bound CymA protein or secreted menaquinone. Using the specific binding affinity of nitric monoxide for the heme groups of c-type cytochromes, we further confirmed this conclusion. The heterogeneous standard rate constant for the DET process was estimated to be 300 {+-} 10 s{sup -1}, which was two orders of magnitude higher than that previously reported for the electron shuttling process via riboflavin. Experiments using a mutant unable to produce capsular polysaccharide ({Delta}SO3177) revealed that the DET property of the OmcA-MtrCAB complex was not influenced by insulating and hydrophilic extracellular polysaccharide. Accordingly, under physiological conditions, S. oneidensis MR-1 utilizes a high density of outer

  3. Effects of recharge and discharge on delta2H and delta18O composition and chloride concentration of high arsenic/fluoride groundwater from the Datong Basin, northern China.

    Science.gov (United States)

    Xie, Xianjun; Wang, Yanxin; Su, Chunli; Duan, Mengyu

    2013-02-01

    To better understand the effects of recharge and discharge on the hydrogeochemistry of high levels of arsenic (As) and fluoride (F) in groundwater, environmental isotopic composition (delta2H and delta18O) and chloride (Cl) concentrations were analyzed in 29 groundwater samples collected from the Datong Basin. High arsenic groundwater samples (As > 50 micog/L) were found to be enriched in lighter isotopic composition that ranged from -92 to -78 per thousand for deuterium (delta2H) and from -12.5 to -9.9 per thousand for oxygen-18 (delta18O). High F-containing groundwater (F > 1 mg/L) was relatively enriched in heavier isotopic composition and varied from -90 to -57 per thousand and from -12.2 to -6.7 per thousand for delta2H and delta18O, respectively. High chloride concentrations and delta18O values were primarily measured in groundwater samples from the northern and southwestern portions of the study area, indicating the effect of evaporation on groundwater. The observation of relatively homogenized and low delta18O values and chloride concentrations in groundwater samples from central part of the Datong Basin might be a result of fast recharge by irrigation returns, which suggests that irrigation using arsenic-contaminated groundwater affected the occurrence of high arsenic-containing groundwater in the basin.

  4. Peroxisome proliferator-activated receptor delta activation leads to increased transintestinal cholesterol efflux

    NARCIS (Netherlands)

    Vrins, Carlos L. J.; van der Velde, Astrid E.; van den Oever, Karin; Levels, Johannes H. M.; Huet, Stephane; Elferink, Ronald P. J. Oude; Kuipers, Folkert; Groen, Albert K.

    2009-01-01

    Peroxisome proliferator-activated receptor delta (PPAR delta) is involved in regulation of energy homeostasis. Activation of PPAR delta markedly increases fecal neutral sterol secretion, the last step in reverse cholesterol transport. This phenomenon can neither be explained by increased

  5. Connecting Past to Present and Watersheds to Ocean: Modeling 165 Years of Incremental Changes to Flows into the San Francisco Bay Delta System

    Science.gov (United States)

    MacVean, L. J.; Thompson, S. E.; Huttom, P. H.; Sivapalan, M.

    2016-02-01

    California's Sacramento-San Joaquin Delta sits at the intersection of vast agricultural and population centers, and supplies fresh water for the diverse and often competing needs of ecosystems, farmers, and millions of Californians. Managing and allocating this resource is a complex feat of economics, politics, and engineering, made increasingly contentious by the ongoing drought. The objective of this research is to augment the scientific foundation of management decisions by addressing the question of how flows into the Delta have evolved in response to human intervention since 1850. In particular, quantifying the dynamic components of water usage through vegetative uptake and evapotranspiration, groundwater recharge, flood conveyance, and water exports at incremental levels of development is a key ambition. This approach emphasizes the built environment, which is subject to the local regulatory framework, rather than climate change, which is generally considered immovable without united global effort. This work encompasses the creation of a hydrologic model representing the watersheds of the San Francisco Bay-Delta system, and quantifies the impacts of changes in land use and the gradual construction of levees, reservoirs, and diversion infrastructure. The model is run using the same climatological forcing at each level of development, thus elucidating the effects of local anthropogenic activity on the Delta and the inflows to the San Francisco Bay estuary. Our results provide a timeline of change, giving decision-makers a scientifically established baseline to aid in the sustainable management of the Bay-Delta system.

  6. Implementation of an ESA delta-DOR capability

    Science.gov (United States)

    James, Nick; Abello, Ricard; Lanucara, Marco; Mercolino, Mattia; Maddè, Roberto

    2009-06-01

    This paper describes the implementation of delta-DOR (delta-differential one-way ranging) receivers within the ESA Deep Space ground station network. Delta-DOR provides very accurate plane-of-sky measurements of spacecraft position which complement existing line-of-sight ranging and Doppler measurements. We discuss how this technique has been adapted and implemented at the two ESA deep-space ground stations using existing equipment and infrastructure. These new capabilities were added by writing new software modules for the standard ESA digital receiver (the intermediate frequency modem system—IFMS). With these upgrades the receiver has the ability to record accurately timetagged signals from up to eight IF sub-channels. These sub-channels can have bandwidths of 50 kHz-2 MHz with a sample quantization of 1-16 bits per component. The IF samples are stored locally for subsequent retrieval over a WAN by the correlator facility at ESOC.

  7. Dynamic controls on shallow clinoform geometry: Mekong Delta, Vietnam

    Science.gov (United States)

    Eidam, E. F.; Nittrouer, C. A.; Ogston, A. S.; DeMaster, D. J.; Liu, J. P.; Nguyen, T. T.; Nguyen, T. N.

    2017-09-01

    Compound deltas, composed of a subaerial delta plain and subaqueous clinoform, are common termini of large rivers. The transition between clinoform topset and foreset, or subaqueous rollover point, is located at 25-40-m water depth for many large tide-dominated deltas; this depth is controlled by removal of sediment from the topset by waves, currents, and gravity flows. However, the Mekong Delta, which has been classified as a mixed-energy system, has a relatively shallow subaqueous rollover at 4-6-m depth. This study evaluates dynamical measurements and seabed cores collected in Sep 2014 and Mar 2015 to understand processes of sediment transfer across the subaqueous delta, and evaluate possible linkages to geometry. During the southwest rainy monsoon (Sep 2014), high river discharge, landward return flow under the river plume, and regional circulation patterns facilitated limited sediment flux to the topset and foreset, and promoted alongshore flux to the northeast. Net observed sediment fluxes in Sep 2014 were landward, however, consistent with hypotheses about seasonal storage on the topset. During the northeast rainy monsoon, low river discharge and wind-driven currents facilitated intense landward and southwestward fluxes of sediment. In both seasons, bed shear velocities frequently exceeded the 0.01-0.02 m/s threshold of motion for sand, even in the absence of strong wave energy. Most sediment transport occurred at water depths 4 cm/yr at energy-limited, and thus rollover depths cannot be predicted solely by bed-stress distributions. In systems like the subaqueous Mekong Delta, direction of transport may have a key impact on morphology.

  8. (La{sub 0.74}Bi{sub 0.10}Sr{sub 0.16})MnO{sub 3-{delta}}-Ce{sub 0.8}Gd{sub 0.2}O{sub 2-{delta}} cathodes fabricated by ion-impregnating method for intermediate-temperature solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Junliang; Wang, Shaorong; Wang, Zhenrong; Liu, Renzhu; Ye, Xiaofeng; Sun, Xiufu; Wen, Tinglian; Wen, Zhaoyin [Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China)

    2009-03-15

    Porous composite cathodes were fabricated by impregnating (La{sub 0.74}Bi{sub 0.10}Sr{sub 0.16})MnO{sub 3-{delta}} (LBSM) electronic conducting structure with the ionic conducting Ce{sub 0.8}Gd{sub 0.2}O{sub 2-{delta}} (GDC) phase. The ion impregnation of the GDC phase significantly enhanced the electrocatalytic activity of the LBSM electrodes for the O{sub 2} reduction reactions, and the ion-impregnated LBSM-GDC composite cathodes showed excellent performance. At 700 C, the value of the cathode polarization resistance (Rc) was only 0.097 {omega} cm{sup 2} for an ion-impregnated LBSM-GDC cathode, and the performance was gradually improved by increasing the loading of the impregnated GDC. For the performance testing of single cells, the maximum power density was 1036 mW cm{sup -2} at 700 C for a cell with the LBSM-GDC cathode. The results demonstrated the unique combination of the LBSM electronic conducting structure with high ionic conducting GDC phase was a valid method to improve the electrode performance, and the ion-impregnated LBSM-GDC was a promising composite cathode material for the intermediate-temperature solid oxide fuel cells. (author)

  9. A new identification method for energetic ion {delta}E-E telescopes

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Cesar [Departamento de Fisica, Universidad de Alcala, 28871 Alcala de Henares, Madrid (Spain); Institut fuer Experimentelle und Angewandte Physik, Christian-Albrechts, Universitaet zu Kiel, 24118 Kiel (Germany); Bronchalo, Enrique [Departamento de Fisica, Universidad de Alcala, 28871 Alcala de Henares, Madrid (Spain); Departamento de Fisica y Arquitectura de Computadores, Universidad Miguel Hernandez, Avda. Universidad s/n, 03202 Elche, Alicante (Spain)], E-mail: ebronchalo@umh.es; Medina, Jose [Departamento de Fisica, Universidad de Alcala, 28871 Alcala de Henares, Madrid (Spain)

    2007-11-21

    A new ion identification method for {delta}E-E telescopes is presented. The method works by counting data points under {delta}E(E) curves on {delta}E-E diagrams. These curves are obtained by simulating the telescope response to a flux of energetic ions. The method is checked against three published methods applied to several experimental data sets.

  10. Inclusive production of. delta. /sup + +/(1232) in pn interactions at 19 GeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Bakken, V.; Breivik, F.O.; Jacobsen, T.; Rudjord, A.L. (Oslo Univ. (Norway) Fysisk Inst.)

    1982-12-21

    We present a study of ..delta../sup + +/ production in pn interactions at 19 GeV/c, where the ..delta../sup + +/ is emitted in the protonlike (..delta..sub(F)/sup + +/) and neutron-like (..delta..sub(B)/sup + +/) c.m. hemispheres. The cross-section sigma(pn->..delta..sub(F)/sup + +/+X)=(3.09+-0.43) mb is about three times larger than sigma(pn->..delta..sub(B)/sup + +/+X)=(0.94+-0.34) mb. About 2/3 of ..delta..sub(F)/sup + +/ is peripherally produced with vertical stroketsub(p,..delta..)vertical stroke<1 (GeV/c)/sup 2/, while the cross-section for ..delta..sub(B)/sup + +/ production is nearly zero for vertical stroketsub(n,..delta..)vertical stroke<1 (GeV/c)/sup 2/. We have made a detailed study of the energy dependence of the reaction ap->..delta../sup + +/+X (a=p, anti p, n, ..pi..sup(+-), Ksup(+-)) for vertical stroketsub(p,..delta..)vertical stroke<1 (GeV/c)/sup 2/, by applying the same fitting procedure to extract the ..delta../sup + +/ cross-section to all available mass spectra. All the normalized cross-sections R=sigma(..delta../sup + +/)/sigmasub(inel) can be well described by R=R/sub 0/+R/sub 1/sup(a)psup(-..cap alpha..)sub(lab), where R/sub 0/ and ..cap alpha.. are the same for all reactions, while R/sub 1/sup(a) varies with the beam type a. The value of ..cap alpha.. is slightly below unity. The differential cross section of pn->..delta..sub(F)/sup + +/+X has been determined as a function of the variables t, t', x, y, psub(T)/sup 2/ and Msub(X)/sup 2/ both in the whole kinematical region and for vertical stroketsub(p,..delta..)vertical stroke<1 (GeV/c)/sup 2/. We show that the peripherally produced ..delta..sub(F)/sup + +/ is consistent with the dominance of the one-pion exchange mechanism. This follows from a study of the density matrix elements, the comparison of some properties of the system X with real ..pi../sup +/p data and from the results of a triple-Regge analysis.

  11. HIV/AIDS, artisanal fishing and food security in the Okavango Delta, Botswana

    Science.gov (United States)

    Ngwenya, B. N.; Mosepele, K.

    Generally, rural households pursue all year round natural and non-natural resource-based livelihood systems to diversify these options in order to cope with risks emanating from a range of shocks and stressors. Artisanal fishing in the Delta is not only a major livelihood option but also a source of food security. This paper is based on analysis of primary data collected from a survey of 248 subsistence fishers’ households through simple random sampling in 22 villages in the Delta. The overall objectives of the survey were to assess the general prevalence of HIV/AIDS in the Ngamiland district of Botswana, to investigate potential effects of AIDS-related stressors, particularly chronic illness on artisanal fishing activities, and to assess implications towards food security. Results from this study indicate that HIV prevalence rates for pregnant women attending antenatal clinics in the Delta are approximately 30% and are related to factors such as marriage, education, and employment. Despite this relatively high prevalence percentage, most of the affected households do not have adequate access to HIV/AIDS support facilities. Support services are provided on the basis of population size and/or status of the settlement (i.e. urban, urban village, rural or remote). Therefore, since about 50% of the Delta’s population lives in settlements of less than 500 people, they receive health services indirectly through major population centres whose capacity to deliver timely HIV/AIDS services is limited. This disproportionate access to HIV/AIDS services disadvantages the majority of fishing communities in the Delta, and may affect their ability to fish. Moreover, about 53% of sampled households had cared for a continuously ill person/s (CIP’s) in the last 5 years, out of which approximately 29% felt that this seriously impacted fishing activities. These serious impacts included sale of family assets, depletion of savings, and switching or abandoning fishing activities

  12. Tautomerism in 5-aminotetrazole investigated by core-level photoelectron spectroscopy and {Delta}SCF calculations

    Energy Technology Data Exchange (ETDEWEB)

    Pinto, R.M., E-mail: ruipinto@fct.unl.pt [CFA, Centro de Fisica Atomica, Departamento de Fisica, Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Dias, A.A. [CFA, Centro de Fisica Atomica, Departamento de Fisica, Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal); Coreno, M. [CNR-IMIP, Montelibretti, Rome I-00016 (Italy); Simone, M. de [CNR-IOM, Laboratorio TASC, 34149 Trieste (Italy); Giuliano, B.M. [Departamento de Quimica da Universidade de Coimbra, 3004-535 Coimbra (Portugal); Santos, J.P.; Costa, M.L. [CFA, Centro de Fisica Atomica, Departamento de Fisica, Faculdade de Ciencias e Tecnologia, FCT, Universidade Nova de Lisboa, 2829-516 Caparica (Portugal)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer High-resolution XPS of 5-aminotetrazole reveals different tautomers. Black-Right-Pointing-Pointer 5ATZ exists mainly in the 2H-form. Black-Right-Pointing-Pointer Results obtained with DSCF are in good agreement with the observed binding energies. - Abstract: The C 1s and N 1s photoelectron spectra of gas-phase 5-aminotetrazole (5ATZ) were recorded using synchrotron radiation, with the aim of evaluating 1H/2H tautomer population ratios. The core-electron binding energies (CEBEs) were estimated from computational results, using the delta self-consistent-field ({Delta}SCF) approach. Simulated spectra were generated using these CEBEs and the results from GAUSSIAN-n (Gn, n = 1, 2 and 3) and Complete Basis Set (CBS-4M and CBS-Q) methods. Results reveal the almost exclusive predominance of the 2H-tautomer, with a 1H/2H ratio of ca. 0.12/0.88, taken from a gross analysis of the XPS C 1s spectrum, recorded at 365 K.

  13. Hydrochemical and Isotopic Composition of The Water Resources In The Po Delta Plain (northern Italy) and Its Environmental Impact

    Science.gov (United States)

    Rapti Caputo, D.; Martinelli, G.

    Groundwater samples from wells were collected to examine the hydrochemical char- acteristics and isotopic composition of the water resources in the Ferrara area (delta Po plain). Electrical conductivity (EC), pH, total dissolved solid (TDS), temperature of the water were directly measured in the field. Subsequently, in the laboratory, the samples were analysed for the determination of major ions such as Ca, Mg, K, Na, SO4, Cl, NO3 and HCO3. Also, oxygen, deuterium and tritium isotopic composition, of the same samples were analysed for the isotopic characterisation of the waters. Three principal water groups can be distinguished on the basis of the distribution of the values of 18O and 2H. The first group (A), include the waters from the wells that exploit the unsatured shallow aquifer, developing in mainly sandy or sandy-silty lenses. These are large diameter wells, whose depth does not exceed the 7 m, while their piezometric level is at depth varying between 2 and 3 m from the soil surface. The isotopic composition of such wells is strongly affected by meteorological events (local recharge). Indeed, the main supply to the aquifer occurs through infiltration, mainly from rainwaters and, secondly, from the waters contained in the drainage channels. The hydrochemical characteristics of the waters coming from those wells present a very high sulphate concentration (up to 508 mg/l). To the second group (B) belong the waters with an 18O and 2H content lower than the previously described group and varying, respectively, between -9.6 Ferrara plain (Po and Po di Volano rivers). In group C, are the waters of the Po River, where low values can be 1 observed both in oxygen and deuterium contents, with values equal to -9.90 s´ 0.03 and -71.3 s´ 0.9, respectively.

  14. Quaternary lacustrine braid deltas on Lake General Carrera in southern Chile Deltas entrelazados lacustres del Cuaternario en el lago General Carrera, sur de Chile

    Directory of Open Access Journals (Sweden)

    C. Mike Bell

    2009-01-01

    Full Text Available A series of Quaternary lacustrine braid deltas on the shores of Lake General Carrera in southern Chile formed as a result of falls in lake level. Each delta comprises two components, the delta fan and the beach embayment, each in turn comprising an onshore subaerial and an offshore subaqueous element. The delta fans have a classic Gilbert form with a braided delta top and a steeply inclined delta front. Adjacent to the fans are concave beach embayments that formed parallel with the deltas as they prograded into the lake. The delta sediments consist predominantly of matrix- and clast-supported gravéis to a total composite thickness exceeding 400 m. The depositional environments are dominated by ephemeral river flooding and by storm-driven waves. Beach sediment is sorted, rounded, winnowed and transported alongshore by waves to fill the beach embayment with ridges of very well sorted and well-rounded gravel. A gently-dipping shoreface platform occurs up to 100 m offshore between the beach and the brink point. From the brink point, in water depth of about 8 m, sediment cascades down the steep delta front slope to form long foresets extending to the lake floor. The sedimentary successions therefore wedge in the opposite direction from those of tectonically controlled basin margins where fan growth keeps pace with basin subsidence.Una serie de deltas entrelazados lacustres, pertenecientes al Cuaternario, ubicados en las costas del lago General Carrera, en el sur de Chile, se formaron como resultado de caídas en el nivel del lago. Cada delta consta de dos componentes: el abanico deltaico y la zona de embahiamiento. Cada uno de ellos tiene, a su vez, un elemento subaéreo costero y un elemento subacuático. Los abanicos deltaicos tienen una forma Gilbert clásica con una parte superior de ríos entrelazados y un frente deltaico empinado. Adyacente a los abanicos aluviales existen bahías cóncavas de playa que se formaron de manera paralela a los

  15. HINS R and D Collaboration on Electron Cloud Effects: Midyear Report

    International Nuclear Information System (INIS)

    Furman, M.A.; Sonnad, K.; Vay, J.-L.

    2006-01-01

    We present a report on ongoing activities on electron-cloud R and D for the MI upgrade. These results update and extend those presented in Refs. 1, 2. In this report we have significantly expanded the parameter range explored in bunch intensity Nb, RMS bunch length σ z and peak secondary emission yield (SEY) (delta) max , but we have constrained our simulations to a field-free region. We describe the threshold behaviors in all of the above three parameters. For (delta) max (ge) 1.5 we find that, even for N b = 1 x 10 11 , the electron cloud density, when averaged over the entire chamber, exceeds the beam neutralization level, but remains significantly below the local neutralization level (ie., when the electron density is computed in the neighborhood of the beam). This 'excess' of electrons is accounted for by narrow regions of high concentration of electrons very close to the chamber surface, especially at the top and bottom of the chamber, akin to virtual cathodes. These virtual cathodes are kept in equilibrium, on average, by a competition between space-charge forces (including their images) and secondary emission, a mechanism that shares some features with the space-charge saturation of the current in a diode at high fields. For N b = 3 x 10 11 the electron cloud build-up growth rate and saturation density have a strong dependence on σ z as σ z decreases below ∼ 0.4 m, when the average electron-wall impact energy roughly reaches the energy E max where (delta) peaks. We also present improved results on emittance growth simulations of the beam obtained with the code WARP/POSINST in quasi-static mode, in which the beam-(electron cloud) interaction is lumped into N s 'stations' around the ring, where N s = 1, 2,..., 9. The emittance shows a rapid growth of ∼ 20% during the first ∼ 100 turns, followed by a much slower growth rate of ∼ 0.03%/turn. Concerning the electron cloud detection technique using microwave transmission, we present an improved

  16. How to deal with subsidence in the Dutch delta?

    NARCIS (Netherlands)

    Stouthamer, E.; Erkens, G.

    2017-01-01

    In many deltas worldwide subsidence still is an underestimated problem, while the threat posed by land subsidence low-lying urbanizing and urbanized deltas exceeds the threat of sea-level rise induced by climate change. Human-induced subsidence is driven by the extraction of hydrocarbons and

  17. Evaluation of DELTA(1232) components in sup 1 sup 2 C

    CERN Document Server

    Bystritsky, V M; Krechetov, Yu F; Saigushkin, O K; Tabachenko, A N; Schuvalov, E N; Grabmayr, R; Fiks, A I

    2001-01-01

    One measured cross section of sup 1 sup 2 C(gamma, pi sup + p) reaction within DELTA(1232)-isobar range. Data analysis was carried out using model taking account of both nucleon and isobar degrees of freedom of sup 1 sup 2 C nucleus. One makes a conclusion that within high transmitted pulses pi sup + p-pairs are formed during DELTA sup + sup + -isobar direct knocking-out of a nucleus. One estimated the probability to determine DELTA-isobar in sup 1 sup 2 C nucleus ground state equal to 0.018 +- 0.005 DELTA-isobar per nucleon

  18. Asymptotic value of screening parameter as determined from the one-electron fragment of the kinetic energy or electrostatic potential at the nucleus

    International Nuclear Information System (INIS)

    Teruya, Hirohide; Anno, Tosinobu

    1985-01-01

    Numerical value of lim sub(Z → infinity) delta(i, j)/delta Zsub(i), where (i, j) stands for average interaction energy of a pair of electrons embedded in hydrogenic orbitals (HAO's) is presented for a wide range of HAO's. Data to be presented should be useful to calculate the asymptotic limit of screening effect seen by an electron embedded in a given kind of orbital for an isoelectronic series of atoms as determined from the ''one-electron component'' of the total kinetic energy of or of the electrostatic potential at the nucleus within an atom. (author)

  19. Design Principles of A Sigma-delta Flux-gate Magnetometer

    Science.gov (United States)

    Magnes, W.; Valavanoglou, A.; Pierce, D.; Frank, A.; Schwingenschuh, K.

    A state-of-the-art flux-gate magnetometer is characterised by magnetic field resolution of several pT in a wide frequency range, low power consumption, low weight and high robustness. Therefore, flux-gate magnetometers are frequently used for ground-based Earth's field observation as well as for measurements aboard scientific space missions. But both traditional analogue and recently developed digital flux-gate magnetometers need low power and high-resolution analogue-to-digital converters for signal quan- tization. The disadvantage of such converters is the low radiation hardness. This fact has led to the idea of combining a traditional analogue flux-gate regulation circuit with that of a discretely realized sigma-delta converter in order to get a radiation hard and further miniaturized magnetometer. The name sigma-delta converter is derived from putting an integrator in front of a 1-bit delta modulator which forms the sigma-delta loop. It is followed by a digital decimation filter realized in a field-programmable gate array (FPGA). The flux-gate regulation and the sigma-delta loop are quite similar in the way of realizing the integrator and feedback circuit, which makes it easy to com- bine these two systems. The presented talk deals with the design principles and the results of a first bread board model.

  20. Stratigraphy and Evolution of Delta Channel Deposits, Jezero Crater, Mars

    Science.gov (United States)

    Goudge, T. A.; Mohrig, D.; Cardenas, B. T.; Hughes, C. M.; Fassett, C. I.

    2017-01-01

    The Jezero impact crater hosted an open-basin lake that was active during the valley network forming era on early Mars. This basin contains a well exposed delta deposit at the mouth of the western inlet valley. The fluvial stratigraphy of this deposit provides a record of the channels that built the delta over time. Here we describe observations of the stratigraphy of the channel deposits of the Jezero western delta to help reconstruct its evolution.