WorldWideScience

Sample records for net portal flux

  1. Effects of particle size and dry matter content of a total mixed ration on intraruminal equilibration and net portal flux of volatile fatty acids in lactating dairy cows

    DEFF Research Database (Denmark)

    Storm, Adam Christian; Kristensen, Niels Bastian

    2010-01-01

    Effects of physical changes in consistency of ruminal contents on intraruminal equilibration and net portal fluxes of volatile fatty acids (VFA) in dairy cows were studied. Four Danish Holstein cows (121 ± 17 d in milk, 591 ± 24 kg of body weight, mean ± SD) surgically fitted with a ruminal cannula...... and permanent indwelling catheters in the major splanchnic blood vessels were used. The experimental design was a 4 × 4 Latin square with a 2 × 2 factorial design of treatments. Treatments differed in forage (grass hay) particle size (FPS; 3.0 and 30 mm) and feed dry matter (DM) content of the total mixed...... ration (44.3 and 53.8%). The feed DM did not affect chewing time, ruminal variables, or net portal flux of VFA. However, decreasing the FPS decreased the overall chewing and rumination times by 151 ± 55 and 135 ± 29 min/d, respectively. No effect of the reduced chewing time was observed on ruminal p...

  2. A Lightweight TwiddleNet Portal

    National Research Council Canada - National Science Library

    Rimikis, Antonios M

    2008-01-01

    TwiddleNet is a distributed architecture of personal servers that harnesses the power of the mobile devices, enabling real time information and file sharing of multiple data types from commercial-off-the-shelf platforms...

  3. A Lightweight TwiddleNet Portal

    Science.gov (United States)

    2008-03-01

    dimensions of 2.8 x 0.7 x 4.6 inches make for a very good tool for TwiddleNet missions. Its Lithium -ion battery with 1200 mAh energy gives approximately...Wireless Connectivity IrDA, Bluetooth, IEEE 802.11b Battery Lithium ion Approximate Dimensions (in) 2.8 x 0.7 x 4.6 Weight (oz) 6.2 ROM 128 MB...designed to exploit the multiple networking modalities available in the current generation of smartphones . TwiddleNet enables well-organized and well

  4. Patient portal readiness among postpartum patients in a safety net setting.

    Science.gov (United States)

    Wieland, Daryl; Gibeau, Anne; Dewey, Caitlin; Roshto, Melanie; Frankel, Hilary

    2017-07-05

    Maternity patients interact with the healthcare system over an approximately ten-month interval, requiring multiple visits, acquiring pregnancy-specific education, and sharing health information among providers. Many features of a web-based patient portal could help pregnant women manage their interactions with the healthcare system; however, it is unclear whether pregnant women in safety-net settings have the resources, skills or interest required for portal adoption. In this study of postpartum patients in a safety net hospital, we aimed to: (1) determine if patients have the technical resources and skills to access a portal, (2) gain insight into their interest in health information, and (3) identify the perceived utility of portal features and potential barriers to adoption. We developed a structured questionnaire to collect demographics from postpartum patients and measure use of technology and the internet, self-reported literacy, interest in health information, awareness of portal functions, and perceived barriers to use. The questionnaire was administered in person to women in an inpatient setting. Of the 100 participants surveyed, 95% reported routine internet use and 56% used it to search for health information. Most participants had never heard of a patient portal, yet 92% believed that the portal functions were important. The two most appealing functions were to check results and manage appointments. Most participants in this study have the required resources such as a device and familiarity with the internet to access a patient portal including an interest in interacting with a healthcare institution via electronic means. Pregnancy is a critical episode of care where active engagement with the healthcare system can influence outcomes. Healthcare systems and portal developers should consider ways to tailor a portal to address the specific health needs of a maternity population including those in a safety net setting.

  5. Spectral estimates of net radiation and soil heat flux

    International Nuclear Information System (INIS)

    Daughtry, C.S.T.; Kustas, W.P.; Moran, M.S.; Pinter, P.J. Jr.; Jackson, R.D.; Brown, P.W.; Nichols, W.D.; Gay, L.W.

    1990-01-01

    Conventional methods of measuring surface energy balance are point measurements and represent only a small area. Remote sensing offers a potential means of measuring outgoing fluxes over large areas at the spatial resolution of the sensor. The objective of this study was to estimate net radiation (Rn) and soil heat flux (G) using remotely sensed multispectral data acquired from an aircraft over large agricultural fields. Ground-based instruments measured Rn and G at nine locations along the flight lines. Incoming fluxes were also measured by ground-based instruments. Outgoing fluxes were estimated using remotely sensed data. Remote Rn, estimated as the algebraic sum of incoming and outgoing fluxes, slightly underestimated Rn measured by the ground-based net radiometers. The mean absolute errors for remote Rn minus measured Rn were less than 7%. Remote G, estimated as a function of a spectral vegetation index and remote Rn, slightly overestimated measured G; however, the mean absolute error for remote G was 13%. Some of the differences between measured and remote values of Rn and G are associated with differences in instrument designs and measurement techniques. The root mean square error for available energy (Rn - G) was 12%. Thus, methods using both ground-based and remotely sensed data can provide reliable estimates of the available energy which can be partitioned into sensible and latent heat under non advective conditions

  6. MetaFluxNet: the management of metabolic reaction information and quantitative metabolic flux analysis.

    Science.gov (United States)

    Lee, Dong-Yup; Yun, Hongsoek; Park, Sunwon; Lee, Sang Yup

    2003-11-01

    MetaFluxNet is a program package for managing information on the metabolic reaction network and for quantitatively analyzing metabolic fluxes in an interactive and customized way. It allows users to interpret and examine metabolic behavior in response to genetic and/or environmental modifications. As a result, quantitative in silico simulations of metabolic pathways can be carried out to understand the metabolic status and to design the metabolic engineering strategies. The main features of the program include a well-developed model construction environment, user-friendly interface for metabolic flux analysis (MFA), comparative MFA of strains having different genotypes under various environmental conditions, and automated pathway layout creation. http://mbel.kaist.ac.kr/ A manual for MetaFluxNet is available as PDF file.

  7. Meaningful use in the safety net: a rapid ethnography of patient portal implementation at five community health centers in California.

    Science.gov (United States)

    Ackerman, Sara L; Sarkar, Urmimala; Tieu, Lina; Handley, Margaret A; Schillinger, Dean; Hahn, Kenneth; Hoskote, Mekhala; Gourley, Gato; Lyles, Courtney

    2017-09-01

    US health care institutions are implementing secure websites (patient portals) to achieve federal Meaningful Use (MU) certification. We sought to understand efforts to implement portals in "safety net" health care systems that provide services for low-income populations. Our rapid ethnography involved visits at 4 California safety net health systems and in-depth interviews at a fifth. Visits included interviews with clinicians and executives ( n  = 12), informal focus groups with front-line staff ( n  = 35), observations of patient portal sign-up procedures and clinic work, review of marketing materials and portal use data, and a brief survey ( n  = 45). Our findings demonstrate that the health systems devoted considerable effort to enlisting staff support for portal adoption and integrating portal-related work into clinic routines. Although all health systems had achieved, or were close to achieving, MU benchmarks, patients faced numerous barriers to portal use and our participants were uncertain how to achieve and sustain "meaningful use" as defined by and for their patients. Health systems' efforts to achieve MU certification united clinic staff under a shared ethos of improved quality of care. However, MU's assumptions about patients' demand for electronic access to health information and ability to make use of it directed clinics' attention to enrollment and message routing rather than to the relevance and usability of a tool that is minimally adaptable to the safety net context. We found a mismatch between MU-based metrics of patient engagement and the priorities and needs of safety net patient populations. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  8. Influence of slow-release urea on nitrogen balance and portal-drained visceral nutrient flux in beef steers

    DEFF Research Database (Denmark)

    Taylor-Edwards, C C; Elam, N A; Kitts, S E

    2009-01-01

    Two experiments were conducted to evaluate the effects of slow-release urea (SRU) versus feed-grade urea on portal-drained visceral (PDV) nutrient flux, nutrient digestibility, and total N balance in beef steers.......Two experiments were conducted to evaluate the effects of slow-release urea (SRU) versus feed-grade urea on portal-drained visceral (PDV) nutrient flux, nutrient digestibility, and total N balance in beef steers....

  9. A Data-Centered Collaboration Portal to Support Global Carbon-Flux Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Agarwal, Deborah A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Humphrey, Marty [Univ. of Virginia, Charlottesville, VA (United States); Beekwilder, Norm [Univ. of Virginia, Charlottesville, VA (United States); Jackson, Keith [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); Goode, Monte [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States); van Ingen, Catharine [Microsoft. San Francisco, CA (United States)

    2009-04-07

    Carbon-climate, like other environmental sciences, has been changing. Large-scalesynthesis studies are becoming more common. These synthesis studies are often conducted by science teams that are geographically distributed and on datasets that are global in scale. A broad array of collaboration and data analytics tools are now available that could support these science teams. However, building tools that scientists actually use is hard. Also, moving scientists from an informal collaboration structure to one mediated by technology often exposes inconsistencies in the understanding of the rules of engagement between collaborators. We have developed a scientific collaboration portal, called fluxdata.org, which serves the community of scientists providing and analyzing the global FLUXNET carbon-flux synthesis dataset. Key things we learned or re-learned during our portal development include: minimize the barrier to entry, provide features on a just-in-time basis, development of requirements is an on-going process, provide incentives to change leaders and leverage the opportunity they represent, automate as much as possible, and you can only learn how to make it better if people depend on it enough to give you feedback. In addition, we also learned that splitting the portal roles between scientists and computer scientists improved user adoption and trust. The fluxdata.org portal has now been in operation for ~;;1.5 years and has become central to the FLUXNET synthesis efforts.

  10. Partitioning of net carbon dioxide flux measured by automatic transparent chamber

    Science.gov (United States)

    Dyukarev, EA

    2018-03-01

    Mathematical model was developed for describing carbon dioxide fluxes at open sedge-sphagnum fen during growing season. The model was calibrated using the results of observations from automatic transparent chamber and it allows us to estimate autotrophic, heterotrophic and ecosystem respiration fluxes, gross and net primary vegetation production, and the net carbon balance.

  11. The education on landslides through the "BE-SAFE-NET" web-portal on Disaster Awareness.

    Science.gov (United States)

    Maquaire, O.; Castaldini, D.; Malet, J.-P.; von Elverfeldt, K.; Pla, F.; Soldati, M.; Greco, R.; Pasuto, A.

    2009-04-01

    The website on Disaster Awareness with the use of the internet "BE-SAFE-NET" is developed within the framework of the FORM-OSE programme (European Training Programme for South, East and West) of the EUR-OPA Major Hazards Agreement, hosted by the European Centre for Disaster Awareness with the use of the internet (BE-SAFE-NET, Nicosia, Cyprus). The website is dedicated for school actors (school-level children, teachers, administrative and technical staff, families and local authorities) in order to: - Inform on regulations, on tools for raising awareness for natural and man-made risks and on preventative measures; - Train children, teachers, administrative and technical staff and local authorities; - Produce interactive figures, photographs, videos and games; - Interact with newsgroups and electronic conferences. Together with the EUR-OPA Centre of Nicosia, the project associates several centres of the Major Hazards Agreement network: the European University for the Cultural Heritage (CUEBC) of Ravello (Italy) the European Centre for Risk Prevention (ECRP) of Sofia (Bulgaria), and the European Centre on Geomorphological Hazards (CERG) of Strasbourg (France). "BE-SAFE-NET" is defined as a network among European countries in order to provide e-learning material on natural hazards and risks primarily for schools (secondary school teachers), but also for the public in general. On the webpage, teachers, pupils and the interested public should find information on disaster prevention, preparation, immediate reaction and rehabilitation. The aim of the paper is to present the structure and the organisation of the web-portal following the pilot project focused on landslides and managed by CERG. Some examples of landslides pedagogical material are also presented. The website is structured in five main sections: 1. About the initiative; 2. Definition of common concepts (e.g. hazard (natural and man made), vulnerability, risk, disaster); 3. Pedagogical material (e.g. case

  12. Analisis dan Perencanaan Konsep Strategi Content Management Cyberwoman pada Situs Portal CBN.Net.Id

    Directory of Open Access Journals (Sweden)

    Suryadiputra Liawatimena

    2007-03-01

    Full Text Available Article discusses how the CyberWoman management strategy on CBN portal site to serve many information, service, and recovery concept that will be used for its better growing. The article purposes are to know whether the content management strategy of portal site applied by CBN, especially for CyberWoman, has been running well or not and also give a recovery concept in the future. The conclusion indicates that the CBN have opportunity and strength that can be used and the CBN portal site is in the state of growing. Therefore, the applied strategy is an aggressive growing policy strategy and concentration strategy through horizontal integration.

  13. NACP North American 8-km Net Ecosystem Exchange and Component Fluxes, 2004

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides modeled carbon flux estimates at 8-km spatial resolution over North America for the year 2004 of (1) net ecosystem exchange (NEE) of...

  14. NACP North American 8-km Net Ecosystem Exchange and Component Fluxes, 2004

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set provides modeled carbon flux estimates at 8-km spatial resolution over North America for the year 2004 of (1) net ecosystem exchange (NEE) of carbon...

  15. Net carbon flux of dead wood in forests of the Eastern US

    Science.gov (United States)

    C.W. Woodall; M.B. Russell; B.F. Walters; A.W. D' Amato; S. Fraver; G.M. Domke

    2015-01-01

    Downed dead wood (DDW) in forest ecosystems is a C pool whose net flux is governed by a complex of natural and anthropogenic processes and is critical to the management of the entire forest C pool. As empirical examination of DDW C net flux has rarely been conducted across large scales, the goal of this study was to use a remeasured inventory of DDW C and ancillary...

  16. Net flux of nutrients across splanchnic tissues of lactating dairy cows as influenced by dietary supplements of biotin and vitamin B12.

    Science.gov (United States)

    Girard, C L; Desrochers, A

    2010-04-01

    Biotin and vitamin B(12) are coenzymes in reactions that are essential to propionate metabolism in dairy cows. The objective of the present studies was to determine whether an increased dietary supply of these vitamins would change the net flux of nutrients through the rumen, the portal-drained viscera (PDV), the total splanchnic tissues (TSP), and the liver. Four lactating cows equipped with ultrasonic flow probes around the right ruminal artery and the portal vein and catheters in the right ruminal vein, the portal vein, one hepatic vein, and one mesenteric artery were fed 12 times per day a mixed ration at 95% of ad libitum dry matter intake. Daily supplements of 500 mg of vitamin B(12)+20mg of biotin or no vitamin supplement (study 1) or 500 mg of vitamin B(12) alone or with 20mg of biotin (study 2) were fed according to a crossover design with two 4-wk periods in each study. On the last day of each period, blood flow was recorded and blood samples were collected every 30 min for 4h. In study 1, biotin and vitamin B(12) given together increased milk production and milk protein yields compared with the control diet. The supplement increased appearance of the 2 vitamins across the PDV and TSP. It also reduced the net portal appearance of ammonia and total volatile fatty acids across the PDV. In study 2, compared with the 2 vitamins together, vitamin B(12) alone increased glucose flux across PDV and TSP as well as its arterial concentration and PDV flux of ammonia. With the diet used in the present experiment, the major effects of the vitamin supplements seem to be mediated through changes in ruminal fermentation and gastrointestinal tract metabolism rather than by effects on hepatic metabolism. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  17. Feasibility study of incore fission chamber application for neutron flux measurements on the NET blanket

    International Nuclear Information System (INIS)

    Bertalot, L.

    1987-01-01

    A feasibility study has been carried out on the use of in-core fission chambers as neutron diagnostic tools to perform neutron flux measurements on the blanket component of NET. The high neutron and gamma fluxes and the severe thermal-mechanical and magnetic conditions of the blanket structure have been taken into account in this analysis. Preliminary design criteria and specifications of an in-core detector are presented for NET application. A research and development programme is outlined which aims to obtain more information on the tecnological constraints arising from the severe conditions of the NET blanket

  18. Barriers and Facilitators to Online Portal Use Among Patients and Caregivers in a Safety Net Health Care System: A Qualitative Study.

    Science.gov (United States)

    Tieu, Lina; Sarkar, Urmimala; Schillinger, Dean; Ralston, James D; Ratanawongsa, Neda; Pasick, Rena; Lyles, Courtney R

    2015-12-03

    Patient portals have the potential to support self-management for chronic diseases and improve health outcomes. With the rapid rise in adoption of patient portals spurred by meaningful use incentives among safety net health systems (a health system or hospital providing a significant level of care to low-income, uninsured, and vulnerable populations), it is important to understand the readiness and willingness of patients and caregivers in safety net settings to access their personal health records online. To explore patient and caregiver perspectives on online patient portal use before its implementation at San Francisco General Hospital, a safety net hospital. We conducted 16 in-depth interviews with chronic disease patients and caregivers who expressed interest in using the Internet to manage their health. Discussions focused on health care experiences, technology use, and interest in using an online portal to manage health tasks. We used open coding to categorize all the barriers and facilitators to portal use, followed by a second round of coding that compared the categories to previously published findings. In secondary analyses, we also examined specific barriers among 2 subgroups: those with limited health literacy and caregivers. We interviewed 11 patients and 5 caregivers. Patients were predominantly male (82%, 9/11) and African American (45%, 5/11). All patients had been diagnosed with diabetes and the majority had limited health literacy (73%, 8/11). The majority of caregivers were female (80%, 4/5), African American (60%, 3/5), caregivers of individuals with diabetes (60%, 3/5), and had adequate health literacy (60%, 3/5). A total of 88% (14/16) of participants reported interest in using the portal after viewing a prototype. Major perceived barriers included security concerns, lack of technical skills/interest, and preference for in-person communication. Facilitators to portal use included convenience, health monitoring, and improvements in patient

  19. Net Ecosystem Fluxes of Hydrocarbons from a Ponderosa Pine Forest in Colorado

    Science.gov (United States)

    Rhew, R. C.; Turnipseed, A. A.; Ortega, J. V.; Smith, J. N.; Guenther, A. B.; Shen, S.; Martinez, L.; Koss, A.; Warneke, C.; De Gouw, J. A.; Deventer, M. J.

    2015-12-01

    Light (C2-C4) alkenes, light alkanes and isoprene (C5H8) are non-methane hydrocarbons that play important roles in the photochemical production of tropospheric ozone and in the formation of secondary organic aerosols. Natural terrestrial fluxes of the light hydrocarbons are poorly characterized, with global emission estimates based on limited field measurements. In 2014, net fluxes of these compounds were measured at the Manitou Experimental Forest Observatory, a semi-arid ponderosa pine forest in the Colorado Rocky Mountains and site of the prior BEACHON campaigns. Three field intensives were conducted between June 17 and August 10, 2014. Net ecosystem flux measurements utilized a relaxed eddy accumulation system coupled to an automated gas chromatograph. Summertime average emissions of ethene and propene were up to 90% larger than those observed from a temperate deciduous forest. Ethene and propene fluxes were also correlated to each other, similar to the deciduous forest study. Emissions of isoprene were small, as expected for a coniferous forest, and these fluxes were not correlated with either ethene or propene. Unexpected emissions of light alkanes were also observed, and these showed a distinct diurnal cycle. Understory flux measurements allowed for the partitioning of fluxes between the surface and the canopy. Full results from the three field intensives will be compared with environmental variables in order to parameterize the fluxes for use in modeling emissions.

  20. Bacterial Flux by Net Precipitation from the Phyllosphere to the Forest Floor.

    Science.gov (United States)

    Pound, P.; Van Stan, J. T., II; Moore, L. D.; Bittar, T.

    2016-12-01

    Transport pathways of microbes between ecosystem spheres (atmosphere, phyllosphere, and pedosphere) represent major fluxes in nutrient cycles and have the potential to significantly affect microbial ecological processes. We quantified a previously unexamined microbial flux from the phyllosphere to the pedosphere during rainfall and found it to be substantial. Net rainfall bacterial fluxes for throughfall and stemflow were quantified using flow cytometry and a quantitative Polymerase Chain Reaction (qPCR) assay for a Quercus virginiana (Mill., southern live oak) forest with heavy epiphyte cover of Tillandsia usneoides (L., Spanish moss) and Pleopeltis polypodiodes (L., resurrection fern) in coastal Georgia (Southeast USA). Total net precipitation flux of bacteria was 15 quadrillion cells year-1 ha-1, which (assuming a bacterial cell mass of 1 pg) is approximately 15 kg of bacterial biomass supply per year. Stemflow generation was low in this stand (rarely exceeded 10 L storm-1) yet still delivered half the annual net precipitation flux due to high bacterial concentration. The role of this previously unquantified bacterial flux in the forest floor has also been under studied, yet it may be significant by contributing functional community members (if living) or labile lysates (if dead).

  1. Criticality Safety Information Resource Center Web portal: www.csirc.net

    International Nuclear Information System (INIS)

    Harmon, C.D. II; Jones, T.

    2000-01-01

    The Nuclear Criticality Safety Group (ESH-6) at Los Alamos National Laboratory (LANL) is in the process of collecting and archiving historical and technical information related to nuclear criticality safety from LANL and other facilities. In an ongoing effort, this information is being made available via the Criticality Safety Information Resource Center (CSIRC) web site, which is hosted and maintained by ESH-6 staff. Recently, the CSIRC Web site was recreated as a Web portal that provides the criticality safety community with much more than just archived data

  2. Estimation of net ecosystem carbon exchange for the conterminous United States by combining MODIS and AmeriFlux data

    Science.gov (United States)

    Jingfeng Xiao; Qianlai Zhuang; Dennis D. Baldocchi; Beverly E. Law; Andrew D. Richardson; Jiquan Chen; Ram Oren; Gegory Starr; Asko Noormets; Siyan Ma; Sashi B. Verma; Sonia Wharton; Steven C. Wofsy; Paul V. Bolstad; Sean P. Burns; David R. Cook; Peter S. Curtis; Bert G. Drake; Matthias Falk; MArc L. Fischer; David R. Foster; Lianhong Gu; Julian L. Hadley; David Y. Hollinger; Gabriel G. Katul; Marcy Litvak; Timothy Martin; Roser Matamala; Steve McNulty; Tilden P. Meyers; Russell K. Monson; J. William Munger; Walter C. Oechel; Kyaw Tha Paw U; Hans Peter Schmid; Russell L. Scott; Ge Sun; Andrew E. Suyker; Margaret S. Torn

    2008-01-01

    Eddy covariance flux towers provide continuous measurements of net ecosystem carbon exchange (NEE) for a wide range of climate and biome types. However, these measurements only represent the carbon fluxes at the scale of the tower footprint. To quantify the net exchange of carbon dioxide between the terrestrial biosphere and the atmosphere for regions or continents,...

  3. Gross nitrous oxide production drives net nitrous oxide fluxes across a salt marsh landscape.

    Science.gov (United States)

    Yang, Wendy H; Silver, Whendee L

    2016-06-01

    Sea level rise will change inundation regimes in salt marshes, altering redox dynamics that control nitrification - a potential source of the potent greenhouse gas, nitrous oxide (N2 O) - and denitrification, a major nitrogen (N) loss pathway in coastal ecosystems and both a source and sink of N2 O. Measurements of net N2 O fluxes alone yield little insight into the different effects of redox conditions on N2 O production and consumption. We used in situ measurements of gross N2 O fluxes across a salt marsh elevation gradient to determine how soil N2 O emissions in coastal ecosystems may respond to future sea level rise. Soil redox declined as marsh elevation decreased, with lower soil nitrate and higher ferrous iron in the low marsh compared to the mid and high marshes (P production was highest in the low marsh and lowest in the mid-marsh (P = 0.02), whereas gross N2 O consumption did not differ among marsh zones. Thus, variability in gross N2 O production rates drove the differences in net N2 O flux among marsh zones. Our results suggest that future studies should focus on elucidating controls on the processes producing, rather than consuming, N2 O in salt marshes to improve our predictions of changes in net N2 O fluxes caused by future sea level rise. © 2015 John Wiley & Sons Ltd.

  4. Temporal and spatial changes in mixed layer properties and atmospheric net heat flux in the Nordic Seas

    International Nuclear Information System (INIS)

    Smirnov, A; Alekseev, G; Korablev, A; Esau, I

    2010-01-01

    The Nordic Seas are an important area of the World Ocean where warm Atlantic waters penetrate far north forming the mild climate of Northern Europe. These waters represent the northern rim of the global thermohaline circulation. Estimates of the relationships between the net heat flux and mixed layer properties in the Nordic Seas are examined. Oceanographic data are derived from the Oceanographic Data Base (ODB) compiled in the Arctic and Antarctic Research Institute. Ocean weather ship 'Mike' (OWS) data are used to calculate radiative and turbulent components of the net heat flux. The net shortwave flux was calculated using a satellite albedo dataset and the EPA model. The net longwave flux was estimated by Southampton Oceanography Centre (SOC) method. Turbulent fluxes at the air-sea interface were calculated using the COARE 3.0 algorithm. The net heat flux was calculated by using oceanographic and meteorological data of the OWS 'Mike'. The mixed layer depth was estimated for the period since 2002 until 2009 by the 'Mike' data as well. A good correlation between these two parameters has been found. Sensible and latent heat fluxes controlled by surface air temperature/sea surface temperature gradient are the main contributors into net heat flux. Significant correlation was found between heat fluxes variations at the OWS 'Mike' location and sea ice export from the Arctic Ocean.

  5. Temporal and spatial changes in mixed layer properties and atmospheric net heat flux in the Nordic Seas

    Energy Technology Data Exchange (ETDEWEB)

    Smirnov, A; Alekseev, G [SI ' Arctic and Antarctic Research Institute' , St. Petersburg (Russian Federation); Korablev, A; Esau, I, E-mail: avsmir@aari.nw.r [Nansen Environmental and Remote Sensing Centre, Bergen (Norway)

    2010-08-15

    The Nordic Seas are an important area of the World Ocean where warm Atlantic waters penetrate far north forming the mild climate of Northern Europe. These waters represent the northern rim of the global thermohaline circulation. Estimates of the relationships between the net heat flux and mixed layer properties in the Nordic Seas are examined. Oceanographic data are derived from the Oceanographic Data Base (ODB) compiled in the Arctic and Antarctic Research Institute. Ocean weather ship 'Mike' (OWS) data are used to calculate radiative and turbulent components of the net heat flux. The net shortwave flux was calculated using a satellite albedo dataset and the EPA model. The net longwave flux was estimated by Southampton Oceanography Centre (SOC) method. Turbulent fluxes at the air-sea interface were calculated using the COARE 3.0 algorithm. The net heat flux was calculated by using oceanographic and meteorological data of the OWS 'Mike'. The mixed layer depth was estimated for the period since 2002 until 2009 by the 'Mike' data as well. A good correlation between these two parameters has been found. Sensible and latent heat fluxes controlled by surface air temperature/sea surface temperature gradient are the main contributors into net heat flux. Significant correlation was found between heat fluxes variations at the OWS 'Mike' location and sea ice export from the Arctic Ocean.

  6. A simple formula for the net long-wave radiation flux in the southern Baltic Sea

    Directory of Open Access Journals (Sweden)

    Tomasz Zapadka

    2001-09-01

    Full Text Available This paper discusses problems of estimating the net long-wave radiation flux at the sea surface on the basis of easily measurable meteorological quantities (air and sea surface temperatures, near-surface water vapour pressure, cloudiness. Empirical data and existing formulae are compared. Additionally, an improved formula for the southern Baltic region is introduced, with a systematic error of less than 1 W -2 and a statistical error of less than 20 W -2.

  7. Ozone flux over a Norway spruce forest and correlation with net ecosystem production

    International Nuclear Information System (INIS)

    Zapletal, Milos; Cudlin, Pavel; Chroust, Petr; Urban, Otmar; Pokorny, Radek; Edwards-Jonasova, Magda; Czerny, Radek; Janous, Dalibor; Taufarova, Klara; Vecera, Zbynek; Mikuska, Pavel; Paoletti, Elena

    2011-01-01

    Daily ozone deposition flux to a Norway spruce forest in Czech Republic was measured using the gradient method in July and August 2008. Results were in good agreement with a deposition flux model. The mean daily stomatal uptake of ozone was around 47% of total deposition. Average deposition velocity was 0.39 cm s -1 and 0.36 cm s -1 by the gradient method and the deposition model, respectively. Measured and modelled non-stomatal uptake was around 0.2 cm s -1 . In addition, net ecosystem production (NEP) was measured by using Eddy Covariance and correlations with O 3 concentrations at 15 m a.g.l., total deposition and stomatal uptake were tested. Total deposition and stomatal uptake of ozone significantly decreased NEP, especially by high intensities of solar radiation. - Highlights: → We estimate ozone deposition flux to a Norway spruce forest using the gradient method and model. → The mean stomatal uptake of ozone is approximately 47% of the total deposition. → We measure net ecosystem production (NEP) using Eddy Covariance. → We test whether elevated total deposition and stomatal uptake of O 3 imply a reduction of NEP. → Deposition and stomatal uptake of O 3 decrease NEP, especially by high intensities of solar radiation. - Net ecosystem production of a Norway spruce forest decreases with increasing deposition and stomatal uptake of ozone.

  8. Net ion fluxes and ammonia excretion during transport of Rhamdia quelen juveniles

    Directory of Open Access Journals (Sweden)

    Luciano de Oliveira Garcia

    2015-10-01

    Full Text Available The objective of this study was to verify net ion fluxes and ammonia excretion in silver catfish transported in plastic bags at three different loading densities: 221, 286 and 365g L-1 for 5h. A water sample was collected at the beginning and at the end of the transport for analysis of water parameters. There was a significant positive relationship between net ion effluxes and negative relationship between ammonia excretion and loading density, demonstrated by the following equations: Na+: y-24.5-0.27x, r2=0.99, Cl-: y=40.2-0.61x, r2=0.98, K+: y=8.0-27.6x, r2=0.94; ammonia excretion: y=-11.43+0.017x, r2=0.95, where y: net ion flux (mmol kg-1 h-1 or ammonia excretion (mg kg-1h-1 and x: loading density (g. Therefore, the increase of loading density increases net ion loss, but reduces ammonia excretion during the transport of silver catfish, indicating the possibility of ammonia accumulation

  9. Grazing alters net ecosystem C fluxes and the global warming potential of a subtropical pasture.

    Science.gov (United States)

    Gomez-Casanovas, Nuria; DeLucia, Nicholas J; Bernacchi, Carl J; Boughton, Elizabeth H; Sparks, Jed P; Chamberlain, Samuel D; DeLucia, Evan H

    2018-03-01

    The impact of grazing on C fluxes from pastures in subtropical and tropical regions and on the environment is uncertain, although these systems account for a substantial portion of global C storage. We investigated how cattle grazing influences net ecosystem CO 2 and CH 4 exchange in subtropical pastures using the eddy covariance technique. Measurements were made over several wet-dry seasonal cycles in a grazed pasture, and in an adjacent pasture during the first three years of grazer exclusion. Grazing increased soil wetness but did not affect soil temperature. By removing aboveground biomass, grazing decreased ecosystem respiration (R eco ) and gross primary productivity (GPP). As the decrease in R eco was larger than the reduction in GPP, grazing consistently increased the net CO 2 sink strength of subtropical pastures (55, 219 and 187 more C/m 2 in 2013, 2014, and 2015). Enteric ruminant fermentation and increased soil wetness due to grazers, increased total net ecosystem CH 4 emissions in grazed relative to ungrazed pasture (27-80%). Unlike temperate, arid, and semiarid pastures, where differences in CH 4 emissions between grazed and ungrazed pastures are mainly driven by enteric ruminant fermentation, our results showed that the effect of grazing on soil CH 4 emissions can be greater than CH 4 produced by cattle. Thus, our results suggest that the interactions between grazers and soil hydrology affecting soil CH 4 emissions play an important role in determining the environmental impacts of this management practice in a subtropical pasture. Although grazing increased total net ecosystem CH 4 emissions and removed aboveground biomass, it increased the net storage of C and decreased the global warming potential associated with C fluxes of pasture by increasing its net CO 2 sink strength. © 2017 by the Ecological Society of America.

  10. Net carbon flux of dead wood in forests of the Eastern US.

    Science.gov (United States)

    Woodall, C W; Russell, M B; Walters, B F; D'Amato, A W; Fraver, S; Domke, G M

    2015-03-01

    Downed dead wood (DDW) in forest ecosystems is a C pool whose net flux is governed by a complex of natural and anthropogenic processes and is critical to the management of the entire forest C pool. As empirical examination of DDW C net flux has rarely been conducted across large scales, the goal of this study was to use a remeasured inventory of DDW C and ancillary forest attributes to assess C net flux across forests of the Eastern US. Stocks associated with large fine woody debris (diameter 2.6-7.6 cm) decreased over time (-0.11 Mg ha(-1) year(-1)), while stocks of larger-sized coarse DDW increased (0.02 Mg ha(-1) year(-1)). Stocks of total DDW C decreased (-0.14 Mg ha(-1) year(-1)), while standing dead and live tree stocks both increased, 0.01 and 0.44 Mg ha(-1) year(-1), respectively. The spatial distribution of DDW C stock change was highly heterogeneous with random forests model results indicating that management history, live tree stocking, natural disturbance, and growing degree days only partially explain stock change. Natural disturbances drove substantial C transfers from the live tree pool (≈-4 Mg ha(-1) year(-1)) to the standing dead tree pool (≈3 Mg ha(-1) year(-1)) with only a minimal increase in DDW C stocks (≈1 Mg ha(-1) year(-1)) in lower decay classes, suggesting a delayed transfer of C to the DDW pool. The assessment and management of DDW C flux is complicated by the diversity of natural and anthropogenic forces that drive their dynamics with the scale and timing of flux among forest C pools remaining a large knowledge gap.

  11. Storage flux uncertainty impact on eddy covariance net ecosystem exchange measurements

    Science.gov (United States)

    Nicolini, Giacomo; Aubinet, Marc; Feigenwinter, Christian; Heinesch, Bernard; Lindroth, Anders; Mamadou, Ossénatou; Moderow, Uta; Mölder, Meelis; Montagnani, Leonardo; Rebmann, Corinna; Papale, Dario

    2017-04-01

    Complying with several assumption and simplifications, most of the carbon budget studies based on eddy covariance (EC) measurements, quantify the net ecosystem exchange (NEE) by summing the flux obtained by EC (Fc) and the storage flux (Sc). Sc is the rate of change of CO2, within the so called control volume below the EC measurement level, given by the difference in the instantaneous profiles of concentration at the beginning and end of the EC averaging period, divided by the averaging period. While cumulating over time led to a nullification of Sc, it can be significant at short time periods. The approaches used to estimate Sc fluxes largely vary, from measurements based only on a single sampling point (usually located at the EC measurement height) to measurements based on several sampling profiles distributed within the control volume. Furthermore, the number of sampling points within each profile vary, according to their height and the ecosystem typology. It follows that measurement accuracy increases with the sampling intensity within the control volume. In this work we use the experimental dataset collected during the ADVEX campaign in which Sc flux has been measured in three similar forest sites by the use of 5 sampling profiles (towers). Our main objective is to quantify the impact of Sc measurement uncertainty on NEE estimates. Results show that different methods may produce substantially different Sc flux estimates, with problematic consequences in case high frequency (half-hourly) data are needed for the analysis. However, the uncertainty on long-term estimates may be tolerate.

  12. Interannual variability of net ecosystem productivity in forests is explained by carbon flux phenology in autumn

    DEFF Research Database (Denmark)

    Wu, Chaoyang; Chen, Xi Jing; Black, T. Andrew

    2013-01-01

    To investigate the importance of autumn phenology in controlling interannual variability of forest net ecosystem productivity (NEP) and to derive new phenological metrics to explain the interannual variability of NEP. North America and Europe. Flux data from nine deciduous broadleaf forests (DBF......, soil water content and precipitation, were also used to explain the phenological variations. We found that interannual variability of NEP can be largely explained by autumn phenology, i.e. the autumn lag. While variation in neither annual gross primary productivity (GPP) nor in annual ecosystem...

  13. Moss and soil contributions to the annual net carbon flux of a maturing boreal forest

    Science.gov (United States)

    Harden, J.W.; O'Neill, K. P.; Trumbore, S.E.; Veldhuis, H.; Stocks, B.J.

    1997-01-01

    We used input and decomposition data from 14C studies of soils to determine rates of vertical accumulation of moss combined with carbon storage inventories on a sequence of burns to model how carbon accumulates in soils and moss after a stand-killing fire. We used soil drainage - moss associations and soil drainage maps of the old black spruce (OBS) site at the BOREAS northern study area (NSA) to areally weight the contributions of each moderately well drained, feathermoss areas; poorly drained sphagnum - feathermoss areas; and very poorly drained brown moss areas to the carbon storage and flux at the OBS NSA site. On this very old (117 years) complex of black spruce, sphagnum bog veneer, and fen systems we conclude that these systems are likely sequestering 0.01-0.03 kg C m-2 yr-' at OBS-NSA today. Soil drainage in boreal forests near Thompson, Manitoba, controls carbon storage and flux by controlling moss input and decomposition rates and by controlling through fire the amount and quality of carbon left after burning. On poorly drained soils rich in sphagnum moss, net accumulation and long-term storage of carbon is higher than on better drained soils colonized by feathermosses. The carbon flux of these contrasting ecosystems is best characterized by soil drainage class and stand age, where stands recently burned are net sources of CO2, and maturing stands become increasingly stronger sinks of atmospheric CO2. This approach to measuring carbon storage and flux presents a method of scaling to larger areas using soil drainage, moss cover, and stand age information.

  14. Can pelagic net heterotrophy account for carbon fluxes from eastern Canadian lakes?

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, Kristal, E-mail: kristal.dubois@gmail.com [Ottawa-Carleton Geoscience Center, University of Ottawa, 140 Louis Pasteur, Ottawa, Ontario, K1N 6N5 (Canada); Carignan, Richard [Departement des Sciences Biologiques, Universite de Montreal C.P. 6128, succ. Centre-Ville, Montreal, Quebec, H3C 3J7 (Canada); Veizer, Jan [Ottawa-Carleton Geoscience Center, University of Ottawa, 140 Louis Pasteur, Ottawa, Ontario, K1N 6N5 (Canada)

    2009-05-15

    Lakes worldwide are commonly oversaturated with CO{sub 2}, however the source of this CO{sub 2} oversaturation is not well understood. To examine the magnitude of the C flux to the atmosphere and determine if an excess of respiration (R) over gross primary production (GPP) is sufficient to account for this C flux, metabolic parameters and stable isotopes of dissolved O{sub 2} and C were measured in 23 Quebec lakes. All of the lakes sampled were oversaturated with CO{sub 2} over the sampling period, on average 221 {+-} 25%. However, little evidence was found to conclude that this CO{sub 2} oversaturation was the result of an excess of pelagic R over GPP. In lakes Croche and a l'Ours, where CO{sub 2} flux, R and GPP were measured weekly, the annual difference between pelagic GPP and R, or net primary production (NPP), was not sufficient to account for the size of the CO{sub 2} flux to the atmosphere. In Lac Croche average annual NPP was 14.4 mg C m{sup -2} d{sup -1} while the average annual flux of CO{sub 2} to the atmosphere was 34 mg C m{sup -2} d{sup -1}. In Lac a l'Ours average annual NPP was -9.1 mg C m{sup -2} d{sup -1} while the average annual flux of CO{sub 2} to the atmosphere was 55 mg C m{sup -2} d{sup -1}. In all of the lakes sampled, O{sub 2} saturation averaged 104.0 {+-} 1.7% during the ice-free season and the isotopic composition of dissolved O{sub 2} ({delta}{sup 18}O{sub DO}) was 22.9 {+-} 0.3 per mille , lower than atmospheric values and indicative of net autotrophy. Carbon evasion was not a function of R, nor did the isotopic signature of dissolved CO{sub 2} in the lakes present evidence of excess R over GPP. External inputs of C must therefore subsidize the lake to explain the continued CO{sub 2} oversaturation. The isotopic composition of dissolved inorganic C ({delta}{sup 13}C{sub DIC}) indicates that the CO{sub 2} oversaturation cannot be attributed to in situ aerobic respiration. {delta}{sup 13}C{sub DIC} reveals a source of excess

  15. Can pelagic net heterotrophy account for carbon fluxes from eastern Canadian lakes?

    International Nuclear Information System (INIS)

    Dubois, Kristal; Carignan, Richard; Veizer, Jan

    2009-01-01

    Lakes worldwide are commonly oversaturated with CO 2 , however the source of this CO 2 oversaturation is not well understood. To examine the magnitude of the C flux to the atmosphere and determine if an excess of respiration (R) over gross primary production (GPP) is sufficient to account for this C flux, metabolic parameters and stable isotopes of dissolved O 2 and C were measured in 23 Quebec lakes. All of the lakes sampled were oversaturated with CO 2 over the sampling period, on average 221 ± 25%. However, little evidence was found to conclude that this CO 2 oversaturation was the result of an excess of pelagic R over GPP. In lakes Croche and a l'Ours, where CO 2 flux, R and GPP were measured weekly, the annual difference between pelagic GPP and R, or net primary production (NPP), was not sufficient to account for the size of the CO 2 flux to the atmosphere. In Lac Croche average annual NPP was 14.4 mg C m -2 d -1 while the average annual flux of CO 2 to the atmosphere was 34 mg C m -2 d -1 . In Lac a l'Ours average annual NPP was -9.1 mg C m -2 d -1 while the average annual flux of CO 2 to the atmosphere was 55 mg C m -2 d -1 . In all of the lakes sampled, O 2 saturation averaged 104.0 ± 1.7% during the ice-free season and the isotopic composition of dissolved O 2 (δ 18 O DO ) was 22.9 ± 0.3 per mille , lower than atmospheric values and indicative of net autotrophy. Carbon evasion was not a function of R, nor did the isotopic signature of dissolved CO 2 in the lakes present evidence of excess R over GPP. External inputs of C must therefore subsidize the lake to explain the continued CO 2 oversaturation. The isotopic composition of dissolved inorganic C (δ 13 C DIC ) indicates that the CO 2 oversaturation cannot be attributed to in situ aerobic respiration. δ 13 C DIC reveals a source of excess C enriched in 13 C, which may be accounted for by anaerobic sediment respiration or groundwater inputs followed by kinetic isotope fractionation during degassing

  16. Quantification of net carbon flux from plastic greenhouse vegetable cultivation: A full carbon cycle analysis

    International Nuclear Information System (INIS)

    Wang Yan; Xu Hao; Wu Xu; Zhu Yimei; Gu Baojing; Niu Xiaoyin; Liu Anqin; Peng Changhui; Ge Ying; Chang Jie

    2011-01-01

    Plastic greenhouse vegetable cultivation (PGVC) has played a vital role in increasing incomes of farmers and expanded dramatically in last several decades. However, carbon budget after conversion from conventional vegetable cultivation (CVC) to PGVC has been poorly quantified. A full carbon cycle analysis was used to estimate the net carbon flux from PGVC systems based on the combination of data from both field observations and literatures. Carbon fixation was evaluated at two pre-selected locations in China. Results suggest that: (1) the carbon sink of PGVC is 1.21 and 1.23 Mg C ha -1 yr -1 for temperate and subtropical area, respectively; (2) the conversion from CVC to PGVC could substantially enhance carbon sink potential by 8.6 times in the temperate area and by 1.3 times in the subtropical area; (3) the expansion of PGVC usage could enhance the potential carbon sink of arable land in China overall. - Highlights: → We used full carbon (C) cycle analysis to estimate the net C flux from cultivation. → The plastic greenhouse vegetable cultivation system in China can act as a C sink. → Intensified agricultural practices can generate C sinks. → Expansion of plastic greenhouse vegetable cultivation can enhance regional C sink. - The conversion from conventional vegetable cultivation to plastic greenhouse vegetable cultivation could substantially enhance carbon sink potential by 8.6 and 1.3 times for temperate and subtropical area, respectively.

  17. Land Use Effects on Net Greenhouse Gas Fluxes in the US Great Plains: Historical Trends and Model Projections

    Science.gov (United States)

    Del Grosso, S. J.; Parton, W. J.; Ojima, D. S.; Mosier, A. R.; Mosier, A. R.; Paustian, K.; Peterson, G. A.

    2001-12-01

    We present maps showing regional patterns of land use change and soil C levels in the US Great Plains during the 20th century and time series of net greenhouse gas fluxes associated with different land uses. Net greenhouse gas fluxes were calculated by accounting for soil CO2 fluxes, the CO2 equivalents of N2O emissions and CH4 uptake, and the CO2 costs of N fertilizer production. Both historical and modern agriculture in this region have been net sources of greenhouse gases. The primary reason for this, prior to 1950, is that agriculture mined soil C and resulted in net CO2 emissions. When chemical N fertilizer became widely used in the 1950's agricultural soils began to sequester CO2-C but these soils were still net greenhouse gas sources if the effects of increased N2O emissions and decreased CH4 uptake are included. The sensitivity of net greenhouse gas fluxes to conventional and alternative land uses was explored using the DAYCENT ecosystem model. Model projections suggest that conversion to no-till, reduction of the fallow period, and use of nitrification inhibitors can significantly decrease net greenhouse gas emissions in dryland and irrigated systems, while maintaining or increasing crop yields.

  18. Nutrient fluxes and net metabolism in a coastal lagoon SW peninsula of Baja California, Mexico

    Directory of Open Access Journals (Sweden)

    Cervantes Duarte, R.

    2016-09-01

    Full Text Available Fluxes of nutrients and net metabolism were estimated in coastal lagoon Magdalena Bay using LOICZ biogeochemical model. In situ data were obtained from 14 sites in the lagoon and also from a fixed site in the adjacent ocean area. Intense upwelling (February to July and faint upwelling (August to January were analyzed from monthly time series. The Temperature, nitrite + nitrate, ammonium and phosphate within the lagoon showed significant differences (p<0.05 between the two periods. Salinity (p=0.408 was more homogeneous (no significantly different due to mixing processes. During the intense upwelling period, nutrients increased in and out of the lagoon due to the influence of Transitional Water and Subartic Water transported by the California Current. However, during the faint upwelling, from August to January, the Transition Water and Subtropical Surface Water were predominant. Magdalena Bay showed denitrification processes of throughout the year as it occurred in other semi-arid coastal lagoons. It also showed a net autotrophic metabolism during intense upwelling and heterotrophic metabolism during faint upwelling. Understanding nutrient flows and net metabolism through simple biogeochemical models can provide tools for better management of the coastal zone.

  19. Bile acid flux through portal but not peripheral veins inhibits CYP7A1 expression without involvement of ileal FGF19 in rabbits.

    Science.gov (United States)

    Shang, Quan; Guo, Grace L; Honda, Akira; Shi, Daniel; Saumoy, Monica; Salen, Gerald; Xu, Guorong

    2014-08-15

    It was proposed that CYP7A1 expression is suppressed through the gut-hepatic signaling pathway fibroblast growth factor (FGF) 15/19-fibroblast growth factor receptor 4, which is initiated by activation of farnesoid X receptor in the intestine rather than in the liver. The present study tested whether portal bile acid flux alone without ileal FGF19 could downregulate CYP7A1 expression in rabbits. A rabbit model was developed by infusing glycodeoxycholic acid (GDCA) through the splenic vein to bypass ileal FGF19. Study was conducted in four groups of rabbits: control; bile fistula + bovine serum albumin solution perfusion (BF); BF + GDCA (by portal perfusion); and BF + GDCA-f (by femoral perfusion). Compared with only BF, BF + GDCA (6 h portal perfusion) suppressed CYP7A1 mRNA, whereas BF + GDCA-f (via femoral vein) with the same perfusion rate of GDCA did not show inhibitory effects. Meanwhile, there was a decrease in ileal FGF19 expression and portal FGF19 protein levels, but an equivalent increase in biliary bile acid outputs in both GDCA perfusion groups. This study demonstrated that portal bile acid flux alone downregulated CYP7A1 expression with diminished FGF19 expression and protein levels, whereas the same bile acid flux reaching the liver through the hepatic artery via femoral vein had no inhibitory effect on CYP7A1. We propose that bile acid flux through the portal venous system may be a kind of "intestinal factor" that suppresses CYP7A1 expression. Copyright © 2014 the American Physiological Society.

  20. Net Fluorescein Flux Across Corneal Endothelium Strongly Suggests Fluid Transport is due to Electro-osmosis.

    Science.gov (United States)

    Sanchez, J M; Cacace, V; Kusnier, C F; Nelson, R; Rubashkin, A A; Iserovich, P; Fischbarg, J

    2016-08-01

    We have presented prior evidence suggesting that fluid transport results from electro-osmosis at the intercellular junctions of the corneal endothelium. Such phenomenon ought to drag other extracellular solutes. We have investigated this using fluorescein-Na2 as an extracellular marker. We measured unidirectional fluxes across layers of cultured human corneal endothelial (HCE) cells. SV-40-transformed HCE layers were grown to confluence on permeable membrane inserts. The medium was DMEM with high glucose and no phenol red. Fluorescein-labeled medium was placed either on the basolateral or the apical side of the inserts; the other side carried unlabeled medium. The inserts were held in a CO2 incubator for 1 h (at 37 °C), after which the entire volume of the unlabeled side was collected. After that, label was placed on the opposite side, and the corresponding paired sample was collected after another hour. Fluorescein counts were determined with a (Photon Technology) DeltaScan fluorometer (excitation 380 nm; emission 550 nm; 2 nm bwth). Samples were read for 60 s. The cells utilized are known to transport fluid from the basolateral to the apical side, just as they do in vivo in several species. We used 4 inserts for influx and efflux (total: 20 1-h periods). We found a net flux of fluorescein from the basolateral to the apical side. The flux ratio was 1.104 ± 0.056. That difference was statistically significant (p = 0.00006, t test, paired samples). The endothelium has a definite restriction at the junctions. Hence, an asymmetry in unidirectional fluxes cannot arise from osmosis, and can only point instead to paracellular solvent drag. We suggest, once more, that such drag is due to electro-osmotic coupling at the paracellular junctions.

  1. Data Driven Estimation of Transpiration from Net Water Fluxes: the TEA Algorithm

    Science.gov (United States)

    Nelson, J. A.; Carvalhais, N.; Cuntz, M.; Delpierre, N.; Knauer, J.; Migliavacca, M.; Ogee, J.; Reichstein, M.; Jung, M.

    2017-12-01

    The eddy covariance method, while powerful, can only provide a net accounting of ecosystem fluxes. Particularly with water cycle components, efforts to partitioning total evapotranspiration (ET) into the biotic component (transpiration, T) and the abiotic component (here evaporation, E) have seen limited success, with no one method emerging as a standard.Here we demonstrate a novel method that uses ecosystem WUE to predict transpiration in two steps: (1) a filtration step that to isolate the signal of ET for periods where E is minimized and ET is likely dominated by the signal of T; and (2) a step which predicts the WUE using meteorological variables, as well as information derived from the carbon and energy fluxes. To assess the the underlying assumptions, we tested the proposed method on three ecological models, allowing validation where the underlying carbon:water relationships, as well as the transpiration estimates, are know.The partitioning method shows high correlation (R²>0.8) between Tmodel/ET and TTEA/ET across timescales from half-hourly to annually, as well as capturing spatial variability across sites. Apart from predictive performance, we explore the sensitivities of the method to the underlying assumptions, such as the effects of residual evaporation in the training dataset. Furthermore, we show initial transpiration estimates from the algorithm at global scale, via the FLUXNET dataset.

  2. Analytical treatment of the relationships between soil heat flux/net radiation ratio and vegetation indices

    International Nuclear Information System (INIS)

    Kustas, W.P.; Daughtry, C.S.T.; Oevelen, P.J. van

    1993-01-01

    Relationships between leaf area index (LAI) and midday soil heat flux/net radiation ratio (G/R n ) and two more commonly used vegetation indices (VIs) were used to analytically derive formulas describing the relationship between G/R n and VI. Use of VI for estimating G/R n may be useful in operational remote sensing models that evaluate the spatial variation in the surface energy balance over large areas. While previous experimental data have shown that linear equations can adequately describe the relationship between G/Rn and VI, this analytical treatment indicated that nonlinear relationships are more appropriate. Data over bare soil and soybeans under a range of canopy cover conditions from a humid climate and data collected over bare soil, alfalfa, and cotton fields in an arid climate were used to evaluate model formulations derived for LAI and G/R n , LAI and VI, and VI and G/R n . In general, equations describing LAI-G/R n and LAI-VI relationships agreed with the data and supported the analytical result of a nonlinear relationship between VI and G/R n . With the simple ratio (NIR/Red) as the VI, the nonlinear relationship with G/R n was confirmed qualitatively. But with the normalized difference vegetation index (NDVI), a nonlinear relationship did not appear to fit the data. (author)

  3. Net ecosystem carbon dioxide exchange in tropical rainforests - sensitivity to environmental drivers and flux measurement methodology

    Science.gov (United States)

    Fu, Z.; Stoy, P. C.

    2017-12-01

    Tropical rainforests play a central role in the Earth system services of carbon metabolism, climate regulation, biodiversity maintenance, and more. They are under threat by direct anthropogenic effects including deforestation and indirect anthropogenic effects including climate change. A synthesis of the factors that determine the net ecosystem exchange of carbon dioxide (NEE) across multiple time scales in different tropical rainforests has not been undertaken to date. Here, we study NEE and its components, gross primary productivity (GPP) and ecosystem respiration (RE), across thirteen tropical rainforest research sites with 63 total site-years of eddy covariance data. Results reveal that the five ecosystems that have greater carbon uptakes (with the magnitude of GPP greater than 3000 g C m-2 y-1) sequester less carbon - or even lose it - on an annual basis at the ecosystem scale. This counterintuitive result is because high GPP is compensated by similar magnitudes of RE. Sites that provided subcanopy CO2 storage observations had higher average magnitudes of GPP and RE and consequently lower NEE, highlighting the importance of measurement methodology for understanding carbon dynamics in tropical rainforests. Vapor pressure deficit (VPD) constrained GPP at all sites, but to differing degrees. Many environmental variables are significantly related to NEE at time scales greater than one year, and NEE at a rainforest in Malaysia is significantly related to soil moisture variability at seasonal time scales. Climate projections from 13 general circulation models (CMIP5) under representative concentration pathway (RCP) 8.5 suggest that many current tropical rainforest sites on the cooler end of the current temperature range are likely to reach a climate space similar to present-day warmer sites by the year 2050, and warmer sites will reach a climate space not currently experienced. Results demonstrate the need to quantify if mature tropical trees acclimate to heat and

  4. Estimation of net ecosystem carbon exchange for the conterminous United States by combining MODIS and AmeriFlux data

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Jingfeng; Zhuang, Qianlai; Baldocchi, Dennis D.; Bolstad, Paul V.; Burns, Sean P.; Chen, Jiquan; Cook, David R.; Curtis, Peter S.; Drake, Bert G.; Foster, David R.; Gu, Lianhong; Hadley, Julian L.; Hollinger, David Y.; Katul, Gabriel G.; Law, Beverly E.; Litvak, Marcy; Ma, Siyan; Martin, Timothy A.; Matamala, Roser; McNulty, Steve; Meyers, Tilden P.; Monson, Russell K.; Munger, J. William; Noormets, Asko; Oechel, Walter C.; Oren, Ram; Richardson, Andrew D.; Schmid, Hans Peter; Scott, Russell L.; Starr, Gregory; Sun, Ge; Suyker, Andrew E.; Torn, Margaret S.; Paw, Kyaw; Verma, Shashi B.; Wharton, Sonia; Wofsy, Steven C.

    2008-10-01

    Eddy covariance flux towers provide continuous measurements of net ecosystem carbon exchange (NEE) for a wide range of climate and biome types. However, these measurements only represent the carbon fluxes at the scale of the tower footprint. To quantify the net exchange of carbon dioxide between the terrestrial biosphere and the atmosphere for regions or continents, flux tower measurements need to be extrapolated to these large areas. Here we used remotely sensed data from the Moderate Resolution Imaging Spectrometer (MODIS) instrument on board the National Aeronautics and Space Administration's (NASA) Terra satellite to scale up AmeriFlux NEE measurements to the continental scale. We first combined MODIS and AmeriFlux data for representative U.S. ecosystems to develop a predictive NEE model using a modified regression tree approach. The predictive model was trained and validated using eddy flux NEE data over the periods 2000-2004 and 2005-2006, respectively. We found that the model predicted NEE well (r = 0.73, p < 0.001). We then applied the model to the continental scale and estimated NEE for each 1 km x 1 km cell across the conterminous U.S. for each 8-day interval in 2005 using spatially explicit MODIS data. The model generally captured the expected spatial and seasonal patterns of NEE as determined from measurements and the literature. Our study demonstrated that our empirical approach is effective for scaling up eddy flux NEE measurements to the continental scale and producing wall-to-wall NEE estimates across multiple biomes. Our estimates may provide an independent dataset from simulations with biogeochemical models and inverse modeling approaches for examining the spatiotemporal patterns of NEE and constraining terrestrial carbon budgets over large areas.

  5. Comprehensive comparison of gap filling techniques for eddy covariance net carbon fluxes

    Science.gov (United States)

    Moffat, A. M.; Papale, D.; Reichstein, M.; Hollinger, D. Y.; Richardson, A. D.; Barr, A. G.; Beckstein, C.; Braswell, B. H.; Churkina, G.; Desai, A. R.; Falge, E.; Gove, J. H.; Heimann, M.; Hui, D.; Jarvis, A. J.; Kattge, J.; Noormets, A.; Stauch, V. J.

    2007-12-01

    Review of fifteen techniques for estimating missing values of net ecosystem CO2 exchange (NEE) in eddy covariance time series and evaluation of their performance for different artificial gap scenarios based on a set of ten benchmark datasets from six forested sites in Europe. The goal of gap filling is the reproduction of the NEE time series and hence this present work focuses on estimating missing NEE values, not on editing or the removal of suspect values in these time series due to systematic errors in the measurements (e.g. nighttime flux, advection). The gap filling was examined by generating fifty secondary datasets with artificial gaps (ranging in length from single half-hours to twelve consecutive days) for each benchmark dataset and evaluating the performance with a variety of statistical metrics. The performance of the gap filling varied among sites and depended on the level of aggregation (native half- hourly time step versus daily), long gaps were more difficult to fill than short gaps, and differences among the techniques were more pronounced during the day than at night. The non-linear regression techniques (NLRs), the look-up table (LUT), marginal distribution sampling (MDS), and the semi-parametric model (SPM) generally showed good overall performance. The artificial neural network based techniques (ANNs) were generally, if only slightly, superior to the other techniques. The simple interpolation technique of mean diurnal variation (MDV) showed a moderate but consistent performance. Several sophisticated techniques, the dual unscented Kalman filter (UKF), the multiple imputation method (MIM), the terrestrial biosphere model (BETHY), but also one of the ANNs and one of the NLRs showed high biases which resulted in a low reliability of the annual sums, indicating that additional development might be needed. An uncertainty analysis comparing the estimated random error in the ten benchmark datasets with the artificial gap residuals suggested that the

  6. Evaluation and uncertainty analysis of regional-scale CLM4.5 net carbon flux estimates

    Science.gov (United States)

    Post, Hanna; Hendricks Franssen, Harrie-Jan; Han, Xujun; Baatz, Roland; Montzka, Carsten; Schmidt, Marius; Vereecken, Harry

    2018-01-01

    Modeling net ecosystem exchange (NEE) at the regional scale with land surface models (LSMs) is relevant for the estimation of regional carbon balances, but studies on it are very limited. Furthermore, it is essential to better understand and quantify the uncertainty of LSMs in order to improve them. An important key variable in this respect is the prognostic leaf area index (LAI), which is very sensitive to forcing data and strongly affects the modeled NEE. We applied the Community Land Model (CLM4.5-BGC) to the Rur catchment in western Germany and compared estimated and default ecological key parameters for modeling carbon fluxes and LAI. The parameter estimates were previously estimated with the Markov chain Monte Carlo (MCMC) approach DREAM(zs) for four of the most widespread plant functional types in the catchment. It was found that the catchment-scale annual NEE was strongly positive with default parameter values but negative (and closer to observations) with the estimated values. Thus, the estimation of CLM parameters with local NEE observations can be highly relevant when determining regional carbon balances. To obtain a more comprehensive picture of model uncertainty, CLM ensembles were set up with perturbed meteorological input and uncertain initial states in addition to uncertain parameters. C3 grass and C3 crops were particularly sensitive to the perturbed meteorological input, which resulted in a strong increase in the standard deviation of the annual NEE sum (σ ∑ NEE) for the different ensemble members from ˜ 2 to 3 g C m-2 yr-1 (with uncertain parameters) to ˜ 45 g C m-2 yr-1 (C3 grass) and ˜ 75 g C m-2 yr-1 (C3 crops) with perturbed forcings. This increase in uncertainty is related to the impact of the meteorological forcings on leaf onset and senescence, and enhanced/reduced drought stress related to perturbation of precipitation. The NEE uncertainty for the forest plant functional type (PFT) was considerably lower (σ ∑ NEE ˜ 4.0-13.5 g C

  7. Deciphering the components of regional net ecosystem fluxes following a bottom-up approach for the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    N. Carvalhais

    2010-11-01

    Full Text Available Quantification of ecosystem carbon pools is a fundamental requirement for estimating carbon fluxes and for addressing the dynamics and responses of the terrestrial carbon cycle to environmental drivers. The initial estimates of carbon pools in terrestrial carbon cycle models often rely on the ecosystem steady state assumption, leading to initial equilibrium conditions. In this study, we investigate how trends and inter-annual variability of net ecosystem fluxes are affected by initial non-steady state conditions. Further, we examine how modeled ecosystem responses induced exclusively by the model drivers can be separated from the initial conditions. For this, the Carnegie-Ames-Stanford Approach (CASA model is optimized at set of European eddy covariance sites, which support the parameterization of regional simulations of ecosystem fluxes for the Iberian Peninsula, between 1982 and 2006.

    The presented analysis stands on a credible model performance for a set of sites, that represent generally well the plant functional types and selected descriptors of climate and phenology present in the Iberian region – except for a limited Northwestern area. The effects of initial conditions on inter-annual variability and on trends, results mostly from the recovery of pools to equilibrium conditions; which control most of the inter-annual variability (IAV and both the magnitude and sign of most of the trends. However, by removing the time series of pure model recovery from the time series of the overall fluxes, we are able to retrieve estimates of inter-annual variability and trends in net ecosystem fluxes that are quasi-independent from the initial conditions. This approach reduced the sensitivity of the net fluxes to initial conditions from 47% and 174% to −3% and 7%, for strong initial sink and source conditions, respectively.

    With the aim to identify and improve understanding of the component fluxes that drive the observed trends, the

  8. Estimation of Net Ecosystem Carbon Exchange for the Conterminous UnitedStates by Combining MODIS and AmeriFlux Data

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Jingfeng; Zhuang, Qianlai; Baldocchi, Dennis D.; Law, Beverly E.; Richardson, Andrew D.; Chen, Jiquan; Oren, Ram; Starr, Gregory; Noormets, Asko; Ma, Siyan; Verma, Shashi B.; Wharton, Sonia; Wofsy, Steven C.; Bolstad, Paul V.; Burns, Sean P.; Cook, David R.; Curtis, Peter S.; Drake, Bert G.; Falk, Matthias; Fischer, Marc L.; Foster, David R.; Gu, Lianhong; Hadley, Julian L.; Hollinger, David Y.; Katul, Gabriel G.; Litvak, Marcy; Martin, Timothy A.; Matamala, Roser; McNulty, Steve; Meyers, Tilden P.; Monson, Russell K.; Munger, J. William; Oechel, Walter C.; U, Kyaw Tha Paw; Schmid, Hans Peter; Scott, Russell L.; Sun, Ge; Suyker, Andrew E.; Torn, Margaret S.

    2009-03-06

    Eddy covariance flux towers provide continuous measurements of net ecosystem carbon exchange (NEE) for a wide range of climate and biome types. However, these measurements only represent the carbon fluxes at the scale of the tower footprint. To quantify the net exchange of carbon dioxide between the terrestrial biosphere and the atmosphere for regions or continents, flux tower measurements need to be extrapolated to these large areas. Here we used remotely-sensed data from the Moderate Resolution Imaging Spectrometer (MODIS) instrument on board NASA's Terra satellite to scale up AmeriFlux NEE measurements to the continental scale. We first combined MODIS and AmeriFlux data for representative U.S. ecosystems to develop a predictive NEE model using a regression tree approach. The predictive model was trained and validated using NEE data over the periods 2000-2004 and 2005-2006, respectively. We found that the model predicted NEE reasonably well at the site level. We then applied the model to the continental scale and estimated NEE for each 1 km x 1 km cell across the conterminous U.S. for each 8-day period in 2005 using spatially-explicit MODIS data. The model generally captured the expected spatial and seasonal patterns of NEE. Our study demonstrated that our empirical approach is effective for scaling up eddy flux NEE measurements to the continental scale and producing wall-to-wall NEE estimates across multiple biomes. Our estimates may provide an independent dataset from simulations with biogeochemical models and inverse modeling approaches for examining the spatiotemporal patterns of NEE and constraining terrestrial carbon budgets for large areas.

  9. Interannual variability of Net Ecosystem CO2 Exchange and its component fluxes in a subalpine Mediterranean ecosystem (SE Spain)

    Science.gov (United States)

    Chamizo, Sonia; Serrano-Ortiz, Penélope; Sánchez-Cañete, Enrique P.; Domingo, Francisco; Arnau-Rosalén, Eva; Oyonarte, Cecilio; Pérez-Priego, Óscar; López-Ballesteros, Ana; Kowalski, Andrew S.

    2015-04-01

    Recent decades under climate change have seen increasing interest in quantifying the carbon (C) balance of different terrestrial ecosystems, and their behavior as sources or sinks of C. Both CO2 exchange between terrestrial ecosystems and the atmosphere and identification of its drivers are key to understanding land-surface feedbacks to climate change. The eddy covariance (EC) technique allows measurements of net ecosystem C exchange (NEE) from short to long time scales. In addition, flux partitioning models can extract the components of net CO2 fluxes, including both biological processes of photosynthesis or gross primary production (GPP) and respiration (Reco), and also abiotic drivers like subsoil CO2 ventilation (VE), which is of particular relevance in semiarid environments. The importance of abiotic processes together with the strong interannual variability of precipitation, which strongly affects CO2 fluxes, complicates the accurate characterization of the C balance in semiarid landscapes. In this study, we examine 10 years of interannual variability of NEE and its components at a subalpine karstic plateau, El Llano de los Juanes, in the Sierra de Gádor (Almería, SE Spain). Results show annual NEE ranging from 55 g C m-2 (net emission) to -54 g C m-2 (net uptake). Among C flux components, GPP was the greatest contributing 42-57% of summed component magnitudes, while contributions by Reco and VE ranged from 27 to 46% and from 3 to 18%, respectively. Annual precipitation during the studied period exhibited high interannual variability, ranging from 210 mm to 1374 mm. Annual precipitation explained 50% of the variance in Reco, 59% of that in GPP, and 56% for VE. While Reco and GPP were positively correlated with annual precipitation (correlation coefficient, R, of 0.71 and 0.77, respectively), VE showed negative correlation with this driver (R = -0.74). During the driest year (2004-2005), annual GPP and Reco reached their lowest values, while contribution of

  10. The influence of cockchafer larvae on net soil methane fluxes under different vegetation types - a mesocosm study

    Science.gov (United States)

    Görres, Carolyn-Monika; Kammann, Claudia; Chesmore, David; Müller, Christoph

    2017-04-01

    The influence of land-use associated pest insects on net soil CH4 fluxes has received little attention thus far, although e.g. soil-dwelling Scarabaeidae larvae are qualitatively known to emit CH4. The project "CH4ScarabDetect" aims to provide the first quantitative estimate of the importance of soil-dwelling larvae of two important European agricultural and forest pest insect species - the common cockchafer (Melolontha melolontha) and the forest cockchafer (M. hippocastani) - for net soil CH4 fluxes. Here we present a mesocosm study within "CH4ScarabDetect" which tests the influence of different abundances of common cockchafer larvae on net soil CH4 fluxes under different vegetation types. In August 2016, 27 PVC boxes with a base area of 50 cm x 50 cm and a height of 40 cm were buried in planting beds previously used for cultivating vegetables. The bottom of each box was filled with a 10 cm thick layer of loam which was then covered with a 25 cm thick layer of loamy sand. The soil was hand-sieved prior to filling the boxes to remove any macrofauna. The mesocosms were planted with either turf, carrots or a combination of both. Of the resulting nine replicates per vegetation type, six were infested with one cockchafer larvae each in November 2016. In three of these infested mesocosms, the larvae abundance will be further increased to three in May 2017. This mesocosm study will continue until October 2017 during which measurements of net soil CH4 fluxes will be conducted with the chamber flux method twice per month. For the in situ separation of gross CH4 production and gross CH4 oxidation, the chamber method will be combined with a 13CH4 isotope pool dilution technique. Methane concentrations and their isotopic signatures in the collected gas samples will be analysed with a state-of-the-art CRDS analyzer (cavity ring-down spectroscopy, G2201-i) equipped with the Small Sample Isotope Module 2 - A0314 (Picarro Inc., USA). Different combinations of larvae abundance and

  11. Inferring CO2 Fluxes from OCO-2 for Assimilation into Land Surface Models to Calculate Net Ecosystem Exchange

    Science.gov (United States)

    Prouty, R.; Radov, A.; Halem, M.; Nearing, G. S.

    2016-12-01

    Investigations of mid to high latitude atmospheric CO2 show a growing seasonal amplitude. Land surface models poorly predict net ecosystem exchange (NEE) and are unable to substantiate these sporadic observations. An investigation of how the biosphere has reacted to changes in atmospheric CO2 is essential to our understanding of potential climate-vegetation feedbacks. A global, seasonal investigation of CO2-flux is then necessary in order to assimilate into land surface models for improving the prediction of annual NEE. The Atmospheric Radiation Measurement program (ARM) of DOE collects CO2-flux measurements (in addition to CO2 concentration and various other meteorological quantities) at several towers located around the globe at half hour temporal frequencies. CO2-fluxes are calculated via the eddy covariance technique, which utilizes CO2-densities and wind velocities to calculate CO2-fluxes. The global coverage of CO2 concentrations as provided by the Orbiting Carbon Observatory (OCO-2) provide satellite-derived CO2 concentrations all over the globe. A framework relating the satellite-inferred CO2 concentrations collocated with the ground-based ARM as well as Ameriflux stations would enable calculations of CO2-fluxes far from the station sites around the entire globe. Regression techniques utilizing deep-learning neural networks may provide such a framework. Additionally, meteorological reanalysis allows for the replacement of the ARM multivariable meteorological variables needed to infer the CO2-fluxes. We present the results of inferring CO2-fluxes from OCO-2 CO2 concentrations for a two year period, Sept. 2014- Sept. 2016 at the ARM station located near Oklahoma City. A feed-forward neural network (FFNN) is used to infer relationships between the following data sets: F([ARM CO2-density], [ARM Meteorological Data]) = [ARM CO2-Flux] F([OCO-2 CO2-density],[ARM Meteorological Data]) = [ARM CO2-Flux] F([ARM CO2-density],[Meteorological Reanalysis]) = [ARM CO2-Flux

  12. Comparisons of a Quantum Annealing and Classical Computer Neural Net Approach for Inferring Global Annual CO2 Fluxes over Land

    Science.gov (United States)

    Halem, M.; Radov, A.; Singh, D.

    2017-12-01

    Investigations of mid to high latitude atmospheric CO2 show growing amplitudes in seasonal variations over the past several decades. Recent high-resolution satellite measurements of CO2 concentration are now available for three years from the Orbiting Carbon Observatory-2. The Atmospheric Radiation Measurement (ARM) program of DOE has been making long-term CO2-flux measurements (in addition to CO2 concentration and an array of other meteorological quantities) at several towers and mobile sites located around the globe at half-hour frequencies. Recent papers have shown CO2 fluxes inferred by assimilating CO2 observations into ecosystem models are largely inconsistent with station observations. An investigation of how the biosphere has reacted to changes in atmospheric CO2 is essential to our understanding of potential climate-vegetation feedbacks. Thus, new approaches for calculating CO2-flux for assimilation into land surface models are necessary for improving the prediction of annual carbon uptake. In this study, we calculate and compare the predicted CO2 fluxes results employing a Feed Forward Backward Propagation Neural Network model on two architectures, (i) an IBM Minsky Computer node and (ii) a hybrid version of the ARC D-Wave quantum annealing computer. We compare the neural net results of predictions of CO2 flux from ARM station data for three different DOE ecosystem sites; an arid plains near Oklahoma City, a northern arctic site at Barrows AL, and a tropical rainforest site in the Amazon. Training times and predictive results for the calculating annual CO2 flux for the two architectures for each of the three sites are presented. Comparative results of predictions as measured by RMSE and MAE are discussed. Plots and correlations of observed vs predicted CO2 flux are also presented for all three sites. We show the estimated training times for quantum and classical calculations when extended to calculating global annual Carbon Uptake over land. We also

  13. Dietary supplementation of branched-chain amino acids increases muscle net amino acid fluxes through elevating their substrate availability and intramuscular catabolism in young pigs.

    Science.gov (United States)

    Zheng, Liufeng; Zuo, Fangrui; Zhao, Shengjun; He, Pingli; Wei, Hongkui; Xiang, Quanhang; Pang, Jiaman; Peng, Jian

    2017-04-01

    Branched-chain amino acids (BCAA) have been clearly demonstrated to have anabolic effects on muscle protein synthesis. However, little is known about their roles in the regulation of net AA fluxes across skeletal muscle in vivo. This study was aimed to investigate the effect and related mechanisms of dietary supplementation of BCAA on muscle net amino acid (AA) fluxes using the hindlimb flux model. In all fourteen 4-week-old barrows were fed reduced-protein diets with or without supplemental BCAA for 28 d. Pigs were implanted with carotid arterial, femoral arterial and venous catheters, and fed once hourly with intraarterial infusion of p-amino hippurate. Arterial and venous plasma and muscle samples were obtained for the measurement of AA, branched-chain α-keto acids (BCKA) and 3-methylhistidine (3-MH). Metabolomes of venous plasma were determined by HPLC-quadrupole time-of-flight-MS. BCAA-supplemented group showed elevated muscle net fluxes of total essential AA, non-essential AA and AA. As for individual AA, muscle net fluxes of each BCAA and their metabolites (alanine, glutamate and glutamine), along with those of histidine, methionine and several functional non-essential AA (glycine, proline and serine), were increased by BCAA supplementation. The elevated muscle net AA fluxes were associated with the increase in arterial and intramuscular concentrations of BCAA and venous metabolites including BCKA and free fatty acids, and were also related to the decrease in the intramuscular concentration of 3-MH. Correlation analysis indicated that muscle net AA fluxes are highly and positively correlated with arterial BCAA concentrations and muscle net BCKA production. In conclusion, supplementing BCAA to reduced-protein diet increases the arterial concentrations and intramuscular catabolism of BCAA, both of which would contribute to an increase of muscle net AA fluxes in young pigs.

  14. Fontes de carboidratos e ionóforo em dietas contendo óleo vegetal para ovinos: digestibilidade, balanço de nitrogênio e fluxo portal de nutrientes Carbohydrate sources and ionophore in sheep diets with vegetal oil: digestibility, nitrogen balance and portal flux of nutrients

    Directory of Open Access Journals (Sweden)

    Gisele Fernanda Mouro

    2006-10-01

    balance and portal nutrient flux in sheep fed high vegetable oil diets. Four Corriedale wethers averaging 54 kg of body weight and fitted with catheters in the mesenteric and portal veins and also in the mesenteric artery were used. Digestibility and nitrogen balance were determined using total collection of feces and urine. Net nutrient flux was calculated using the Fick principle. Intake, fecal excretion, digestion and digestibility of dry matter (DM, organic matter (OM and ether extract (EE were not affected by treatments. However, intake, digestion and digestibility of neutral detergent fiber (NDF were higher when animals were fed soybean hulls (757.0 g/d, 531.1 g/d and 70.2% rather than corn grain (392.3, 199.9 g/d and 51.0%. Conversely, intake, digestion and digestibility of nonfiber carbohydrates (NFC as well as TDN content were greater on corn (474.6 g/d, 416.8 g/d, 87.8%, 80.2% than on soybean hulls diets (148.0 g/d, 97.8 g/d and 66.1%, 76.7%. There was no effect of monensin on nutrient digestibility and nitrogen balance. Fecal excretion of protein was lower and protein digestibility was higher for corn diets. Alpha-amino-nitrogen concentration in arterial and portal plasma was lower for diets supplemented with monensin (3.161 and 2.922 mM compared to non-supplemented monsesin diets (3.530 and 3.218 mM, respectively. Portal concentration (0.419 vs. 0.516 mM, venous-arterial difference (0.230 vs. 0.317 mM, and portal flux (26.119 vs. 37.041 mM/h of ammonia were all lower on corn diets.

  15. Net ecosystem exchange and energy fluxes measured with the eddy covariance technique in a western Siberian bog

    Directory of Open Access Journals (Sweden)

    P. Alekseychik

    2017-08-01

    Full Text Available Very few studies of ecosystem–atmosphere exchange involving eddy covariance data have been conducted in Siberia, with none in the western Siberian middle taiga. This work provides the first estimates of carbon dioxide (CO2 and energy budgets in a typical bog of the western Siberian middle taiga based on May–August measurements in 2015. The footprint of measured fluxes consisted of a homogeneous mixture of tree-covered ridges and hollows with the vegetation represented by typical sedges and shrubs. Generally, the surface exchange rates resembled those of pine-covered bogs elsewhere. The surface energy balance closure approached 100 %. Net CO2 uptake was comparatively high, summing up to 202 gC m−2 for the four measurement months, while the Bowen ratio was seasonally stable at 28 %. The ecosystem turned into a net CO2 source during several front passage events in June and July. The periods of heavy rain helped keep the water table at a sustainably high level, preventing a usual drawdown in summer. However, because of the cloudy and rainy weather, the observed fluxes might rather represent the special weather conditions of 2015 than their typical magnitudes.

  16. Biometric-based estimation of net ecosystem production in a mature Japanese cedar (Cryptomeria japonica) plantation beneath a flux tower.

    Science.gov (United States)

    Yashiro, Yuichiro; Lee, Na-Yeon M; Ohtsuka, Toshiyuki; Shizu, Yoko; Saitoh, Taku M; Koizumi, Hiroshi

    2010-07-01

    Quantification of carbon budgets and cycling in Japanese cedar (Cryptomeria japonica D. Don) plantations is essential for understanding forest functions in Japan because these plantations occupy about 20% of the total forested area. We conducted a biometric estimate of net ecosystem production (NEP) in a mature Japanese cedar plantation beneath a flux tower over a 4-year period. Net primary production (NPP) was 7.9 Mg C ha(-1) year(-1) and consisted mainly of tree biomass increment and aboveground litter production. Respiration was calculated as 6.8 (soil) and 3.3 (root) Mg C ha(-1) year(-1). Thus, NEP in the plantation was 4.3 Mg C ha(-1) year(-1). In agreement with the tower-based flux findings, this result suggests that the Japanese cedar plantation was a strong carbon sink. The biometric-based NEP was higher among most other types of Japanese forests studied. Carbon sequestration in the mature plantation was characterized by a larger increment in tree biomass and lower mortality than in natural forests. Land-use change from natural forest to Japanese cedar plantation might, therefore, stimulate carbon sequestration and change the carbon allocation of NPP from an increment in coarse woody debris to an increase in tree biomass.

  17. Ozone flux over a Norway spruce forest and correlation with net ecosystem production

    Czech Academy of Sciences Publication Activity Database

    Zapletal, M.; Cudlín, Pavel; Chroust, P.; Urban, Otmar; Pokorný, Radek; Edwards, Magda; Czerný, Radek; Janouš, Dalibor; Taufarová, Klára; Večeřa, Zbyněk; Mikuška, Pavel; Paoletti, E.

    2011-01-01

    Roč. 159, č. 5 (2011), s. 1024-1034 ISSN 0269-7491 R&D Projects: GA MŽP SP/1B7/189/07 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z40310501 Keywords : ozone deposition * stomatal conductance * deposition velocity * friction velocity * gradient method * tropospheric ozone * net ecosystem production Subject RIV: EH - Ecology, Behaviour Impact factor: 3.746, year: 2011

  18. Spatial and temporal variations in net carbon flux during HAPEX-Sahel.

    NARCIS (Netherlands)

    Moncrieff, J.B.; Monteny, B.; Verhoef, A.; Friborg, Th.; Elbers, J.; Kabat, P.; DeBruin, H.; Soegaard, H.; Jarvis, P.G.; Taupin, J.D.

    1997-01-01

    Micrometeorological measurements of the surface flux of carbon dioxide were made at a number of spatially separate sites within the HAPEX-Sahel experimental area. Differences in the timing of plant development caused by differences in rainfall (both quantity and frequency) over the experimental area

  19. Glucagon-like peptide-2 (GLP-2) increases net amino acid utilization by the portal-drained viscera of ruminating calves

    DEFF Research Database (Denmark)

    Taylor-Edwards, C C; Burrin, D G; Kristensen, Niels Bastian

    2012-01-01

    Glucagon-like peptide-2 (GLP-2) increases small intestinal mass and blood flow in ruminant calves, but its impact on nutrient metabolism across the portal-drained viscera (PDV) and liver is unknown. Eight Holstein calves with catheters in the carotid artery, mesenteric vein, portal vein and hepat...

  20. Portal Hypertension

    Science.gov (United States)

    ... Overview of Gallbladder Cancer Additional Content Medical News Portal Hypertension By Steven K. Herrine, MD, Professor of Medicine, ... Liver Hepatic Encephalopathy Jaundice in Adults Liver Failure Portal Hypertension Portal hypertension is abnormally high blood pressure in ...

  1. Net ion fluxes in the facultative air-breather Hoplosternum littorale (tamoata) and the obligate air-breather Arapaima gigas (pirarucu) exposed to different Amazonian waters.

    Science.gov (United States)

    Baldisserotto, Bernardo; Copatti, Carlos E; Gomes, Levy C; Chagas, Edsandra C; Brinn, Richard P; Roubach, Rodrigo

    2008-12-01

    Fishes that live in the Amazon environment may be exposed to several kinds of water: black water (BW), acidic black water (pH 3.5) (ABW) and white water (WW), among others. The aim of the present study was to analyze net ion fluxes in the facultative air-breather Hoplosternum littorale (tamoata) and the obligate air-breather Arapaima gigas (pirarucu) exposed to different types of water. Fishes were acclimated in well water and later placed in individual chambers containing one type of water for ion flux measurements. After 4 h, the water in the chambers was replaced by a different type of water. The transfer of both species to ABW (independent of previous water exposure) increased net ion loss. Tamoatas transferred from ABW to BW or WW presented a net ion influx, but pirarucus showed only small changes on net ion efflux. These results allow us to conclude that tamoatas and pirarucus present differences in terms of ion regulation but that the general aspects of the ion flux are similar: (1) exposure to ABW led to net ion loss; (2) transfer from BW to WW or vice-versa induced only minor changes on net ion fluxes. These observations demonstrate that any osmoregulatory difficulties encountered by either species during changes between these latter two waters can be easily overcome.

  2. Statistical partitioning of a three-year time series of direct urban net CO2 flux measurements into biogenic and anthropogenic components

    Science.gov (United States)

    Menzer, Olaf; McFadden, Joseph P.

    2017-12-01

    Eddy covariance flux measurements are increasingly used to quantify the net carbon dioxide exchange (FC) in urban areas. FC represents the sum of anthropogenic emissions, biogenic carbon release from plant and soil respiration, and carbon uptake by plant photosynthesis. When FC is measured in natural ecosystems, partitioning into respiration and photosynthesis is a well-established procedure. In contrast, few studies have partitioned FC at urban flux tower sites due to the difficulty of accounting for the temporal and spatial variability of the multiple sources and sinks. Here, we partitioned a three-year time series of flux measurements from a suburban neighborhood of Minneapolis-Saint Paul, Minnesota, USA. We segregated FC into one subset that captured fluxes from a residential neighborhood and into another subset that covered a golf course. For both land use types we modeled anthropogenic flux components based on winter data and extrapolated them to the growing season, to estimate gross primary production (GPP) and ecosystem respiration (Reco) at half-hourly, daily, monthly and annual scales. During the growing season, GPP had the largest magnitude (up to - 9.83 g C m-2 d-1) of any component CO2 flux, biogenic or anthropogenic, and both GPP and Reco were more dynamic seasonally than anthropogenic fluxes. Owing to the balancing of Reco against GPP, and the limitations of the growing season in a cold temperate climate zone, the net biogenic flux was only 1.5%-4.5% of the anthropogenic flux in the dominant residential land use type, and between 25%-31% of the anthropogenic flux in highly managed greenspace. Still, the vegetation sink at our site was stronger than net anthropogenic emissions on 16-20 days over the residential area and on 66-91 days over the recreational area. The reported carbon flux sums and dynamics are a critical step toward developing models of urban CO2 fluxes within and across cities that differ in vegetation cover.

  3. The Net Carbon Flux due to Deforestation and Forest Re-Growth in the Brazilian Amazon: Analysis using a Process-Based Model

    Science.gov (United States)

    Hirsch, A. I.; Little, W. S.; Houghton, R. A.; Scott, N. A.; White, J. D.

    2004-01-01

    We developed a process-based model of forest growth, carbon cycling, and land cover dynamics named CARLUC (for CARbon and Land Use Change) to estimate the size of terrestrial carbon pools in terra firme (non-flooded) forests across the Brazilian Legal Amazon and the net flux of carbon resulting from forest disturbance and forest recovery from disturbance. Our goal in building the model was to construct a relatively simple ecosystem model that would respond to soil and climatic heterogeneity that allows us to study of the impact of Amazonian deforestation, selective logging, and accidental fire on the global carbon cycle. This paper focuses on the net flux caused by deforestation and forest re-growth over the period from 1970-1998. We calculate that the net flux to the atmosphere during this period reached a maximum of approx. 0.35 PgC/yr (1PgC = 1 x 10(exp I5) gC) in 1990, with a cumulative release of approx. 7 PgC from 1970- 1998. The net flux is higher than predicted by an earlier study by a total of 1 PgC over the period 1989-1 998 mainly because CARLUC predicts relatively high mature forest carbon storage compared to the datasets used in the earlier study. Incorporating the dynamics of litter and soil carbon pools into the model increases the cumulative net flux by approx. 1 PgC from 1970-1998, while different assumptions about land cover dynamics only caused small changes. The uncertainty of the net flux, calculated with a Monte-Carlo approach, is roughly 35% of the mean value (1 SD).

  4. UU* filtering of nighttime net ecosystem CO2 exchange flux over forest canopy under strong wind in wintertime

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Junhui

    2005-01-01

    [1]Aubinet, M., Heinesch, B., Longdoz, B., Estimation of the carbon sequestration by a heterogeneous forest: night flux corrections,heterogeneity of the site and inter-annual variability, Global Change Biology, 2002, 8:1053-1071.[2]Charlotte, L.R., Nigel, T.R., Seasonal contribution of CO2 fluxes in the annual C budget of a northern bog, Global Biogeochemical Cycles, 2003, 171029, doi: 10.1029/20029B001889.[3]Baldocchi, D.D., Hicks, B.B., Meyers, T. P., Measuring biosphere-atmosphere exchanges of biologically related gases with micrometeorological methods, Ecology, 1988, 69:1331-1340.[4]Baldocchi, D.D., Assessing ecosystem carbon balance: problems and prospects of the eddy covariance technique, Global change biology, 2003, 9: 478-492.[5]Canadell, J. G., Mooney, H. A., Baldocchi, D. D. et al., Carbon metabolism of the terrestrial biosphere: A multi technique approach for improved understanding, Ecosystems, 2000, 3:115-130.[6]Schmid, H. P., Footprint modeling for vegetation atmosphere exchange studies: a review and perspective, Agricultural and Forest Meteorology, 2002, 113: 159-183.[7]Wofsy, S. C., Goulden, M. L., Munger, J. W. et al., Net exchange on CO2 in a mid-latitude forest, Science, 1993, 260: 1314-1317.[8]Massman, W. J., Lee, X. H., Eddy covariance flux corrections and uncertainties in long-term studies of carbon and energy exchanges,Agricultural and Forest Meteorology, 2002, 113: 121-144.[9]Baldocchi, D. D., Finnigan, J., Wilson, K. et al., On measuring net ecosystem carbon exchange over tall vegetation on complex terrain, Boundary-Layer Meteorology, 2000, 96: 257-291.[10]Anthoni, P. M., Unsworth, M. H., Law, B. E. et al., Seasonal differences in carbon and water vapor exchange in young and old-growth ponderosa pine ecosystems, Agricultural and Forest Meteorology, 2002, 111: 203-222.[11]Paw U, K. T., Baldocchi, D. D., Meyers, T. P. et al., Correction of eddy-covariance measurements incorporating both advective

  5. Net ecosystem exchange of CO2 and H2O fluxes from irrigated grain sorghum and maize in the Texas High Plains

    Science.gov (United States)

    Net ecosystem exchange (NEE) of carbon dioxide (CO2) and water vapor (H2O) fluxes from irrigated grain sorghum (Sorghum bicolor L. Moench) and maize (Zea mays L.) fields in the Texas High Plains were quantified using the eddy covariance (EC) technique during 2014-2016 growing seasons and examined in...

  6. Assessing net ecosystem carbon exchange of U S terrestrial ecosystems by integrating eddy covariance flux measurements and satellite observations

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, Qianlai [Purdue University; Law, Beverly E. [Oregon State University; Baldocchi, Dennis [University of California, Berkeley; Ma, Siyan [University of California, Berkeley; Chen, Jiquan [University of Toledo, Toledo, OH; Richardson, Andrew [Harvard University; Melillo, Jerry [Marine Biological Laboratory; Davis, Ken J. [Pennsylvania State University; Hollinger, D. [USDA Forest Service; Wharton, Sonia [University of California, Davis; Falk, Matthias [University of California, Davis; Paw, U. Kyaw Tha [University of California, Davis; Oren, Ram [Duke University; Katulk, Gabriel G. [Duke University; Noormets, Asko [North Carolina State University; Fischer, Marc [Lawrence Berkeley National Laboratory (LBNL); Verma, Shashi [University of Nebraska; Suyker, A. E. [University of Nebraska, Lincoln; Cook, David R. [Argonne National Laboratory (ANL); Sun, G. [USDA Forest Service; McNulty, Steven G. [USDA Forest Service; Wofsy, Steve [Harvard University; Bolstad, Paul V [University of Minnesota; Burns, Sean [University of Colorado, Boulder; Monson, Russell K. [University of Colorado, Boulder; Curtis, Peter [Ohio State University, The, Columbus; Drake, Bert G. [Smithsonian Environmental Research Center, Edgewater, MD; Foster, David R. [Harvard University; Gu, Lianhong [ORNL; Hadley, Julian L. [Harvard University; Litvak, Marcy [University of New Mexico, Albuquerque; Martin, Timothy A. [University of Florida, Gainesville; Matamala, Roser [Argonne National Laboratory (ANL); Meyers, Tilden [NOAA, Oak Ridge, TN; Oechel, Walter C. [San Diego State University; Schmid, H. P. [Indiana University; Scott, Russell L. [USDA ARS; Torn, Margaret S. [Lawrence Berkeley National Laboratory (LBNL)

    2011-01-01

    More accurate projections of future carbon dioxide concentrations in the atmosphere and associated climate change depend on improved scientific understanding of the terrestrial carbon cycle. Despite the consensus that U.S. terrestrial ecosystems provide a carbon sink, the size, distribution, and interannual variability of this sink remain uncertain. Here we report a terrestrial carbon sink in the conterminous U.S. at 0.63 pg C yr 1 with the majority of the sink in regions dominated by evergreen and deciduous forests and savannas. This estimate is based on our continuous estimates of net ecosystem carbon exchange (NEE) with high spatial (1 km) and temporal (8-day) resolutions derived from NEE measurements from eddy covariance flux towers and wall-to-wall satellite observations from Moderate Resolution Imaging Spectroradiometer (MODIS). We find that the U.S. terrestrial ecosystems could offset a maximum of 40% of the fossil-fuel carbon emissions. Our results show that the U.S. terrestrial carbon sink varied between 0.51 and 0.70 pg C yr 1 over the period 2001 2006. The dominant sources of interannual variation of the carbon sink included extreme climate events and disturbances. Droughts in 2002 and 2006 reduced the U.S. carbon sink by 20% relative to a normal year. Disturbances including wildfires and hurricanes reduced carbon uptake or resulted in carbon release at regional scales. Our results provide an alternative, independent, and novel constraint to the U.S. terrestrial carbon sink.

  7. Turbulent Convection Insights from Small-Scale Thermal Forcing with Zero Net Heat Flux at a Horizontal Boundary.

    Science.gov (United States)

    Griffiths, Ross W; Gayen, Bishakhdatta

    2015-11-13

    A large-scale circulation, a turbulent boundary layer, and a turbulent plume are noted features of convection at large Rayleigh numbers under differential heating on a single horizontal boundary. These might be attributed to the forcing, which in all studies has been limited to a unidirectional gradient over the domain scale. We instead apply forcing on a length scale smaller than the domain, and with variation in both horizontal directions. Direct numerical simulations show turbulence throughout the domain, a regime transition to a dominant domain-scale circulation, and a region of logarithmic velocity in the boundary layer, despite zero net heat flux. The results show significant similarities to Rayleigh-Bénard convection, demonstrate the significance of plume merging, support the hypothesis that the key driver of convection is the production of available potential energy without necessarily supplying total potential energy, and imply that contributions to domain-scale circulation in the oceans need not be solely from the large-scale gradients of forcing.

  8. A Comparison of Three Gap Filling Techniques for Eddy Covariance Net Carbon Fluxes in Short Vegetation Ecosystems

    Directory of Open Access Journals (Sweden)

    Xiaosong Zhao

    2015-01-01

    Full Text Available Missing data is an inevitable problem when measuring CO2, water, and energy fluxes between biosphere and atmosphere by eddy covariance systems. To find the optimum gap-filling method for short vegetations, we review three-methods mean diurnal variation (MDV, look-up tables (LUT, and nonlinear regression (NLR for estimating missing values of net ecosystem CO2 exchange (NEE in eddy covariance time series and evaluate their performance for different artificial gap scenarios based on benchmark datasets from marsh and cropland sites in China. The cumulative errors for three methods have no consistent bias trends, which ranged between −30 and +30 mgCO2 m−2 from May to October at three sites. To reduce sum bias in maximum, combined gap-filling methods were selected for short vegetation. The NLR or LUT method was selected after plant rapidly increasing in spring and before the end of plant growing, and MDV method was used to the other stage. The sum relative error (SRE of optimum method ranged between −2 and +4% for four-gap level at three sites, except for 55% gaps at soybean site, which also obviously reduced standard deviation of error.

  9. Accretion disc dynamo activity in local simulations spanning weak-to-strong net vertical magnetic flux regimes

    Science.gov (United States)

    Salvesen, Greg; Simon, Jacob B.; Armitage, Philip J.; Begelman, Mitchell C.

    2016-03-01

    Strongly magnetized accretion discs around black holes have attractive features that may explain enigmatic aspects of X-ray binary behaviour. The structure and evolution of these discs are governed by a dynamo-like mechanism, which channels part of the accretion power liberated by the magnetorotational instability (MRI) into an ordered toroidal magnetic field. To study dynamo activity, we performed three-dimensional, stratified, isothermal, ideal magnetohydrodynamic shearing box simulations. The strength of the self-sustained toroidal magnetic field depends on the net vertical magnetic flux, which we vary across almost the entire range over which the MRI is linearly unstable. We quantify disc structure and dynamo properties as a function of the initial ratio of mid-plane gas pressure to vertical magnetic field pressure, β _0^mid = p_gas / p_B. For 10^5 ≥ β _0^mid ≥ 10 the effective α-viscosity parameter scales as a power law. Dynamo activity persists up to and including β _0^mid = 10^2, at which point the entire vertical column of the disc is magnetic pressure dominated. Still stronger fields result in a highly inhomogeneous disc structure, with large density fluctuations. We show that the turbulent steady state βmid in our simulations is well matched by the analytic model of Begelman et al. describing the creation and buoyant escape of toroidal field, while the vertical structure of the disc can be broadly reproduced using this model. Finally, we discuss the implications of our results for observed properties of X-ray binaries.

  10. Estimation of Community Land Model parameters for an improved assessment of net carbon fluxes at European sites

    Science.gov (United States)

    Post, Hanna; Vrugt, Jasper A.; Fox, Andrew; Vereecken, Harry; Hendricks Franssen, Harrie-Jan

    2017-03-01

    The Community Land Model (CLM) contains many parameters whose values are uncertain and thus require careful estimation for model application at individual sites. Here we used Bayesian inference with the DiffeRential Evolution Adaptive Metropolis (DREAM(zs)) algorithm to estimate eight CLM v.4.5 ecosystem parameters using 1 year records of half-hourly net ecosystem CO2 exchange (NEE) observations of four central European sites with different plant functional types (PFTs). The posterior CLM parameter distributions of each site were estimated per individual season and on a yearly basis. These estimates were then evaluated using NEE data from an independent evaluation period and data from "nearby" FLUXNET sites at 600 km distance to the original sites. Latent variables (multipliers) were used to treat explicitly uncertainty in the initial carbon-nitrogen pools. The posterior parameter estimates were superior to their default values in their ability to track and explain the measured NEE data of each site. The seasonal parameter values reduced with more than 50% (averaged over all sites) the bias in the simulated NEE values. The most consistent performance of CLM during the evaluation period was found for the posterior parameter values of the forest PFTs, and contrary to the C3-grass and C3-crop sites, the latent variables of the initial pools further enhanced the quality-of-fit. The carbon sink function of the forest PFTs significantly increased with the posterior parameter estimates. We thus conclude that land surface model predictions of carbon stocks and fluxes require careful consideration of uncertain ecological parameters and initial states.

  11. Whole Watershed Quantification of Net Carbon Fluxes by Erosion and Deposition within the Christina River Basin Critical Zone Observatory

    Science.gov (United States)

    Aufdenkampe, A. K.; Karwan, D. L.; Aalto, R. E.; Marquard, J.; Yoo, K.; Wenell, B.; Chen, C.

    2013-12-01

    We have proposed that the rate at which fresh, carbon-free minerals are delivered to and mix with fresh organic matter determines the rate of carbon preservation at a watershed scale (Aufdenkampe et al. 2011). Although many studies have examined the role of erosion in carbon balances, none consider that fresh carbon and fresh minerals interact. We believe that this mechanism may be a dominant sequestration process in watersheds with strong anthropogenic impacts. Our hypothesis - that the rate of mixing fresh carbon with fresh, carbon-free minerals is a primary control on watershed-scale carbon sequestration - is central to our Christina River Basin Critical Zone Observatory project (CRB-CZO, http://www.udel.edu/czo/). The Christina River Basin spans 1440 km2 from piedmont to Atlantic coastal plain physiographic provinces in the states of Pennsylvania and Delaware, and experienced intensive deforestation and land use beginning in the colonial period of the USA. Here we present a synthesis of multi-disciplinary data from the CRB-CZO on materials as they are transported from sapprolite to topsoils to colluvium to suspended solids to floodplains, wetlands and eventually to the Delaware Bay estuary. At the heart of our analysis is a spatially-integrated, flux-weighted comparison of the organic carbon to mineral surface area ratio (OC/SA) of erosion source materials versus transported and deposited materials. Because source end-members - such as forest topsoils, farmed topsoils, gullied subsoils and stream banks - represent a wide distribution of initial, pre-erosion OC/SA, we quantify source contributions using geochemical sediment fingerprinting approaches (Walling 2005). Analytes used for sediment fingerprinting include: total mineral elemental composition (including rare earth elements), fallout radioisotope activity for common erosion tracers (beryllium-7, beryllium-10, lead-210, cesium-137), particle size distribution and mineral specific surface area, in addition

  12. Measuring titratable alkalinity by single versus double endpoint titration: An evaluation in two cyprinodont species and implications for characterizing net H+ flux in aquatic organisms.

    Science.gov (United States)

    Brix, Kevin V; Wood, Chris M; Grosell, Martin

    2013-01-01

    In this study, Na(+) uptake and acid-base balance in the euryhaline pupfish Cyprinodon variegatus variegatus were characterized when fish were exposed to pH 4.5 freshwater (7mM Na(+)). Similar to the related cyprinodont, Fundulus heteroclitus, Na(+) uptake was significantly inhibited when exposed to low pH water. However, it initially appeared that C. v. variegatus increased apparent net acid excretion at low pH relative to circumneutral pH. This result is opposite to previous observations for F. heteroclitus under similar conditions where fish were observed to switch from apparent net H(+) excretion at circumneutral pH to apparent net H(+) uptake at low pH. Further investigation revealed disparate observations between these studies were the result of using double endpoint titrations to measure titratable alkalinity fluxes in the current study, while the earlier study utilized single endpoint titrations to measure these fluxes (i.e.,. Cyprinodon acid-base transport is qualitatively similar to Fundulus when characterized using single endpoint titrations). This led to a comparative investigation of these two methods. We hypothesized that either the single endpoint methodology was being influenced by a change in the buffer capacity of the water (e.g., mucus being released by the fish) at low pH, or the double endpoint methodology was not properly accounting for ammonia flux by the fish. A series of follow-up experiments indicated that buffer capacity of the water did not change significantly, that excretion of protein (a surrogate for mucus) was actually reduced at low pH, and that the double endpoint methodology does not properly account for NH(3) excretion by fish under low pH conditions. As a result, it overestimates net H(+) excretion during low pH exposure. After applying the maximum possible correction for this error (i.e., assuming that all ammonia is excreted as NH(3)), the double endpoint methodology indicates that net H(+) transport was reduced to

  13. The NUCLEONICA Nuclear Science Portal

    International Nuclear Information System (INIS)

    Magill, Joseph; Dreher, Raymond

    2009-01-01

    NUCLEONICA (www.nucleonica.net) is a new nuclear science web portal which provides a customisable, integrated environment and collaboration platform using the latest internet 'Web 2.0' technology. NUCLEONICA is aimed at professionals, academics and students working in nuclear power, health physics and radiation protection, nuclear and radio-chemistry, and astrophysics. A unique feature of the portal is the wide range of user friendly web-based nuclear science applications. The portal is also ideal for education and training purposes and as a knowledge management platform to preserve nuclear knowledge built up over many decades.

  14. Flux

    DEFF Research Database (Denmark)

    Ravn, Ib

    . FLUX betegner en flyden eller strømmen, dvs. dynamik. Forstår man livet som proces og udvikling i stedet for som ting og mekanik, får man et andet billede af det gode liv end det, som den velkendte vestlige mekanicisme lægger op til. Dynamisk forstået indebærer det gode liv den bedst mulige...... kanalisering af den flux eller energi, der strømmer igennem os og giver sig til kende i vore daglige aktiviteter. Skal vores tanker, handlinger, arbejde, samvær og politiske liv organiseres efter stramme og faste regelsæt, uden slinger i valsen? Eller skal de tværtimod forløbe ganske uhindret af regler og bånd...

  15. Estimating regional terrestrial carbon fluxes for the Australian continent using a multiple-constraint approach. I. Using remotely sensed data and ecological observations of net primary production

    International Nuclear Information System (INIS)

    Ying Ping Wang; Barrett, Damian J.

    2003-01-01

    We have developed a modelling framework that synthesizes various types of field measurements at different spatial and temporal scales. We used this modelling framework to estimate monthly means and their standard deviations of gross photosynthesis, total ecosystem production, net primary production (NPP) and net ecosystem production (NEP) for eight regions of the Australian continent between 1990 and 1998. Annual mean NPP of the Australian continent varied between 800 and 1100 Mt C/yr between 1990 and 1998, with a coefficient of variation that is defined as the ratio of standard deviation and mean between 0.24 and 0.34. The seasonal variation of NPP for the whole continent varied between 50 and 110 Mt C/month with two maxima, one in the autumn and another in the spring. NEP was most negative in the winter (a carbon sink) and was most positive (a carbon source) in the summer. However, the coefficient of variation of monthly mean NEP was very large (> 4), and consequently confidence in the predicted net carbon fluxes for any month in the period 1990-1998 for the whole continent was very low. A companion paper will apply atmospheric inverse technique to measurements of CO 2 concentration to further constrain the continental carbon cycle and reduce uncertainty in estimated mean monthly carbon fluxes

  16. Estimation of the soil heat flux/net radiation ratio based on spectral vegetation indexes in high-latitude Arctic areas

    International Nuclear Information System (INIS)

    Jacobsen, A.; Hansen, B.U.

    1999-01-01

    The vegetation communities in the Arctic environment are very sensitive to even minor climatic variations and therefore the estimation of surface energy fluxes from high-latitude vegetated areas is an important subject to be pursued. This study was carried out in July-August and used micro meteorological data, spectral reflectance signatures, and vegetation biomass to establish the relation between the soil heat flux/net radiation (G / Rn) ratio and spectral vegetation indices (SVIs). Continuous measurements of soil temperature and soil heat flux were used to calculate the surface ground heat flux by use of conventional methods, and the relation to surface temperature was investigated. Twenty-seven locations were established, and six samples per location, including the measurement of the surface temperature and net radiation to establish the G/Rn ratio and simultaneous spectral reflectance signatures and wet biomass estimates, were registered. To obtain regional reliability, the locations were chosen in order to represent the different Arctic vegetation communities in the study area; ranging from dry tundra vegetation communities (fell fields and dry dwarf scrubs) to moist/wet tundra vegetation communities (snowbeds, grasslands and fens). Spectral vegetation indices, including the simple ratio vegetation index (RVI) and the normalized difference vegetation index (NDVI), were calculated. A comparison of SVIs to biomass proved that RVI gave the best linear expression, and NDVI the best exponential expression. A comparison of SVIs and the surface energy flux ratio G / Rn proved that NDVI gave the best linear expression. SPOT HRV images from July 1989 and 1992 were used to map NDVI and G / Rn at a regional scale. (author)

  17. Establishment of the National Nuclear Regulatory Portal (NNRP) as the key element of the Global Nuclear Safety and Security Network and Regulatory Network (GNSSN/RegNet) for sharing of nuclear safety information and knowledge among the Global Expert Community

    International Nuclear Information System (INIS)

    Kuvshinnikov, A.V.

    2011-01-01

    The Global Nuclear Safety and Security Network (GNSSN) implements the concept of the Global Nuclear Safety and Security Framework (GNSSF) as outlined in INSAG 21. This is the framework of instruments and resources for achieving and maintaining worldwide a high level of safety and security at nuclear facilities and activities as stated in SF-1 and supporting safety standards or recommendations such as INSAG-12. National efforts are and should be augmented by the activities of a variety of international enterprises that facilitate safety and security. The IAEA standard GS-R-3 requires that information and knowledge is managed as a resource. Further strengthening of GNSSN in particular regulatory networking as intended by GNSSN/RegNet has to be based on current national priorities, on existing regional and thematic networks and on the established mechanisms of international co-operation as presented for example on the websites of the IAEA or the OECD-NEA. Current design and operation of RegNet are flexible enough to accommodate differences in national and international approaches and practices and to facilitate exchange and cooperation on regulatory matters. The main role of GNSSN/RegNet is sharing knowledge and bringing people together to enhance and promote nuclear safety and security. The objectives of GNSSN/RegNet: enhancing safety and security by international cooperation, sharing information and best practices, enabling adequate access to relevant safety and security information and promoting the dissemination of this information, implementing active collaboration in the relevant areas related to safety and security, such as joint projects, peer reviews, enabling synergies among existing networks and initiatives, informing the public on the relevant safety and security areas and the related international collaboration. In the RegNet part of the GNSSN exist the National Nuclear Regulatory Portal (NNRP) which is on one hand a part of the global RegNet and on the

  18. Partitioning of the net CO2 exchange using an automated chamber system reveals plant phenology as key control of production and respiration fluxes in a boreal peatland.

    Science.gov (United States)

    Järveoja, Järvi; Nilsson, Mats B; Gažovič, Michal; Crill, Patrick M; Peichl, Matthias

    2018-04-30

    The net ecosystem CO 2 exchange (NEE) drives the carbon (C) sink-source strength of northern peatlands. Since NEE represents a balance between various production and respiration fluxes, accurate predictions of its response to global changes require an in depth understanding of these underlying processes. Currently, however, detailed information of the temporal dynamics as well as the separate biotic and abiotic controls of the NEE component fluxes is lacking in peatland ecosystems. In this study, we address this knowledge gap by using an automated chamber system established across natural and trenching-/vegetation removal plots to partition NEE into its production (i.e. gross and net primary production; GPP and NPP) and respiration (i.e. ecosystem, heterotrophic and autotrophic respiration; ER, Rh and Ra) fluxes in a boreal peatland in northern Sweden. Our results showed that daily NEE patterns were driven by GPP while variations in ER were governed by Ra rather than Rh. Moreover, we observed pronounced seasonal shifts in the Ra/Rh and above-/belowground NPP ratios throughout the main phenological phases. Generalized linear model analysis revealed that the greenness index derived from digital images (as a proxy for plant phenology) was the strongest control of NEE, GPP and NPP while explaining considerable fractions also in the variations of ER and Ra. In addition, our data exposed greater temperature sensitivity of NPP compared to Rh resulting in enhanced C sequestration with increasing temperature. Overall, our study suggests that the temporal patterns in NEE and its component fluxes are tightly coupled to vegetation dynamics in boreal peatlands and thus challenges previous studies that commonly identify abiotic factors as key drivers. These findings further emphasize the need for integrating detailed information on plant phenology into process-based models to improve predictions of global change impacts on the peatland C cycle. This article is protected by

  19. GEO portal

    Data.gov (United States)

    US Agency for International Development — The USAID GeoPortal is a new application that groups web-based capabilities for on-demand discovery of and access to geospatial content, services, expertise, and...

  20. Combining tower mixing ratio and community model data to estimate regional-scale net ecosystem carbon exchange by boundary layer inversion over four flux towers in the United States

    Science.gov (United States)

    Xueri Dang; Chun-Ta Lai; David Y. Hollinger; Andrew J. Schauer; Jingfeng Xiao; J. William Munger; Clenton Owensby; James R. Ehleringer

    2011-01-01

    We evaluated an idealized boundary layer (BL) model with simple parameterizations using vertical transport information from community model outputs (NCAR/NCEP Reanalysis and ECMWF Interim Analysis) to estimate regional-scale net CO2 fluxes from 2002 to 2007 at three forest and one grassland flux sites in the United States. The BL modeling...

  1. Revised estimates of the annual net flux of carbon to the atmosphere from changes in land use and land management 1850-2000

    International Nuclear Information System (INIS)

    Houghton, R.A.

    2003-01-01

    Recent analyses of land-use change in the US and China, together with the latest estimates of tropical deforestation and afforestation from the FAO, were used to calculate a portion of the annual flux of carbon between terrestrial ecosystems and the atmosphere. The calculated flux includes only that portion of the flux resulting from direct human activity. In most regions, activities included the conversion of natural ecosystems to cultivated lands and pastures, including shifting cultivation, harvest of wood (for timber and fuel) and the establishment of tree plantations. In the US, woody encroachment and woodland thickening as a result of fire suppression were also included. The calculated flux of carbon does not include increases or decreases in carbon storage as a result of environmental changes (e.g.; increasing concentrations of CO 2 , N deposition, climatic change or pollution). Globally, the long-term (1850-2000) flux of carbon from changes in land use and management released 156 PgC to the atmosphere, about 60% of it from the tropics. Average annual fluxes during the 1980s and 1990s were 2.0 and 2.2 PgC/yr, respectively, dominated by releases of carbon from the tropics. Outside the tropics, the average net flux of carbon attributable to land-use change and management decreased from a source of 0.06 PgC/yr during the 1980s to a sink of 0.02 PgC/yr during the 1990s. According to the analyses summarized here, changes in land use were responsible for sinks in North America and Europe and for small sources in other non-tropical regions. The revisions were as large as 0.3 PgC/yr in individual regions but were largely offsetting, so that the global estimate for the 1980s was changed little from an earlier estimate. Uncertainties and recent improvements in the data used to calculate the flux of carbon from land-use change are reviewed, and the results are compared to other estimates of flux to evaluate the extent to which processes other than land-use change and

  2. Assessing the net effect of long-term drainage on a permafrost ecosystem through year-round eddy-covariance flux measurements

    Science.gov (United States)

    Kittler, F.; Heimann, M.; Goeckede, M.; Zimov, S. A.; Zimov, N.

    2014-12-01

    Permafrost regions in the Northern high latitudes play a key role in the carbon budget of the earth system because of their massive carbon reservoir and the uncertain feedback processes with future climate change. For an improved understanding of mechanisms and drivers dominating permafrost carbon cycling, more observations in high-latitude regions are needed. Particularly the contribution of wintertime fluxes to the annual carbon budget and the impact of disturbances on biogeochemical and biogeophysical ecosystem properties, and the resulting modification of the carbon cycle, have rarely been studied to date. In summer of 2013, we established a new eddy-covariance station for continuous, year-round monitoring of carbon fluxes and their environmental drivers near Cherskii in Northeast Siberia (68.75°N, 161.33°E). Parts of the observation area have been disturbed by drainage since 2004, altering the soil water conditions in a way that is expected for degrading ice-rich permafrost under a warming climate. With two eddy-covariance towers running in parallel over the disturbed (drained) area and a reference area nearby, respectively, we can directly infer the disturbance effect on the carbon cycle budgets and the dominating biogeochemical mechanisms. This study presents findings based on 16 months of continuous eddy-covariance CO2 flux measurements (July 2013 - October 2014) for both observation areas. At both towers, we observed systematic, non-zero flux contributions outside the growing seasons that significantly altered annual CO2 budgets. A direct comparison of fluxes between the two disturbance regimes indicates a net reduction of the sink strength for CO2 in the disturbed area during the growing season, mostly caused by reduced CO2 uptake with low water levels in late summer. Moreover, shifts in soil temperatures and snow cover caused by reduced soil water levels result in lower net CO2 emissions during the winter at the drained area, which is partly

  3. Iron fertilization enhanced net community production but not downward particle flux during the Southern Ocean iron fertilization experiment LOHAFEX

    Digital Repository Service at National Institute of Oceanography (India)

    Martin, P.; Loeff, M.M.R. van der.; Cassar, N.; Vandromme, P.; d'Ovidio, F.; Stemmann, L.; Rengarajan, R.; Soares, M.A.; Gonzalez, H.E.; Ebersbach, F.; Lampitt, R.S.; Sanders, R.; Barnett, B.A.; Smetacek, V.; Naqvi, S.W.A.

    A closed eddy core in the Subantarctic Atlantic Ocean was fertilized twice with two tons of iron (as FeSO4), and the 300 km2 fertilized patch was studied for 39 days to test whether fertilization enhances downward particle flux...

  4. Comparison of 37 months global net radiation flux derived from PICARD-BOS over the same period observations of CERES and ARGO

    Science.gov (United States)

    Zhu, Ping; Wild, Martin

    2016-04-01

    The absolute level of the global net radiation flux (NRF) is fixed at the level of [0.5-1.0] Wm-2 based on the ocean heat content measurements [1]. The space derived global NRF is at the same order of magnitude than the ocean [2]. Considering the atmosphere has a negligible effects on the global NRF determination, the surface global NRF is consistent with the values determined from space [3]. Instead of studying the absolute level of the global NRF, we focus on the interannual variation of global net radiation flux, which were derived from the PICARD-BOS experiment and its comparison with values over the same period but obtained from the NASA-CERES system and inferred from the ocean heat content survey by ARGO network. [1] Allan, Richard P., Chunlei Liu, Norman G. Loeb, Matthew D. Palmer, Malcolm Roberts, Doug Smith, and Pier-Luigi Vidale (2014), Changes in global net radiative imbalance 1985-2012, Geophysical Research Letters, 41 (no.15), 5588-5597. [2] Loeb, Norman G., John M. Lyman, Gregory C. Johnson, Richard P. Allan, David R. Doelling, Takmeng Wong, Brian J. Soden, and Graeme L. Stephens (2012), Observed changes in top-of-the-atmosphere radiation and upper-ocean heating consistent within uncertainty, Nature Geoscience, 5 (no.2), 110-113. [3] Wild, Martin, Doris Folini, Maria Z. Hakuba, Christoph Schar, Sonia I. Seneviratne, Seiji Kato, David Rutan, Christof Ammann, Eric F. Wood, and Gert Konig-Langlo (2015), the energy balance over land and oceans: an assessment based on direct observations and CMIP5 climate models, Climate Dynamics, 44 (no.11-12), 3393-3429.

  5. [Effects of drip irrigation with plastic mulching on the net primary productivity, soil heterotrophic respiration, and net CO2 exchange flux of cotton field ecosystem in Xinjiang, Northwest China].

    Science.gov (United States)

    Li, Zhi-Guo; Zhang, Run-Hua; Lai, Dong-Mei; Yan, Zheng-Yue; Jiang, Li; Tian, Chang-Yan

    2012-04-01

    In April-October, 2009, a field experiment was conducted to study the effects of drip irrigation with plastic mulching (MD) on the net primary productivity (NPP), soil heterotrophic respiration (Rh) , and net CO2 exchange flux (NEF(CO2)) of cotton field ecosystem in Xinjiang, taking the traditional flood irrigation with no mulching (NF) as the control. With the increasing time, the NPP, Rh, and NEF(CO2) in treatments MD and NF all presented a trend of increasing first and decreased then. As compared with NF, MD increased the aboveground and belowground biomass and the NPP of cotton, and decreased the Rh. Over the whole growth period, the Rh in treatment MD (214 g C x m(-2)) was smaller than that in treatment NF (317 g C x m(-2)), but the NEF(CO2) in treatment MD (1030 g C x m(-2)) was higher than that in treatment NF (649 g C x m(-2)). Treatment MD could fix the atmospheric CO2 approximately 479 g C x m(-2) higher than treatment NF. Drip irrigation with plastic mulching could promote crop productivity while decreasing soil CO2 emission, being an important agricultural measure for the carbon sequestration and emission reduction of cropland ecosystems in arid area.

  6. ASH External Web Portal (External Portal) -

    Data.gov (United States)

    Department of Transportation — The ASH External Web Portal is a web-based portal that provides single sign-on functionality, making the web portal a single location from which to be authenticated...

  7. Portal Vein Thrombosis

    Directory of Open Access Journals (Sweden)

    Hakan Demirci

    2016-01-01

    Full Text Available Portal vein thrombosis is an important cause of presinusoidal portal hypertension. Portal vein thrombosis commonly occurs in patient with cirrhosis, malignancy and prothrombotic states. Patients with acute portal vein thrombosis have immediate onset. Patients with chronic portal vein thrombosis have developed portal hypertension and cavernous portal transformation. Portal vein thrombosis is diagnosed with doppler ultrasound, computed tomography and magnetic resonance imaging. Therapy with low molecular weight heparin achieves recanalization in more than half of acute cases.

  8. Portal manga

    OpenAIRE

    Temprano Hernandez, Joan

    2011-01-01

    El projecte Portal Manga pretén construir una aplicació web que ha de permetre a una empresa anunciar els seus productes a la web, disposar de una botiga virtual en la que es puguin adquirir aquests productes en format digital i finalment un lector web que en permeti la lectura online.

  9. Estimation of daytime net ecosystem CO2 exchange over balsam fir forests in eastern Canada : combining averaged tower-based flux measurements with remotely sensed MODIS data

    International Nuclear Information System (INIS)

    Hassan, Q.K.; Bourque, C.P.A.; Meng, F-R.

    2006-01-01

    Considerable attention has been placed on the unprecedented increases in atmospheric carbon dioxide (CO 2 ) emissions and associated changes in global climate change. This article developed a practical approach for estimating daytime net CO 2 fluxes generated over balsam fir dominated forest ecosystems in the Atlantic Maritime ecozone of eastern Canada. The study objectives were to characterize the light use efficiency and ecosystem respiration for young to intermediate-aged balsam fir forest ecosystems in New Brunswick; relate tower-based measurements of daytime net ecosystem exchange (NEE) to absorbed photosynthetically active radiation (APAR); use a digital elevation model of the province to enhance spatial calculations of daily photosynthetically active radiation and APAR under cloud-free conditions; and generate a spatial calculation of daytime NEE for a balsam fir dominated region in northwestern New Brunswick. The article identified the study area and presented the data requirements and methodology. It was shown that the seasonally averaged daytime NEE and APAR values are strongly correlated. 36 refs., 2 tabs., 10 figs

  10. Net sea–air CO2 flux uncertainties in the Bay of Biscay based on the choice of wind speed products and gas transfer parameterizations

    Directory of Open Access Journals (Sweden)

    P. Otero

    2013-05-01

    Full Text Available The estimation of sea–air CO2 fluxes is largely dependent on wind speed through the gas transfer velocity parameterization. In this paper, we quantify uncertainties in the estimation of the CO2 uptake in the Bay of Biscay resulting from the use of different sources of wind speed such as three different global reanalysis meteorological models (NCEP/NCAR 1, NCEP/DOE 2 and ERA-Interim, one high-resolution regional forecast model (HIRLAM-AEMet, winds derived under the Cross-Calibrated Multi-Platform (CCMP project, and QuikSCAT winds in combination with some of the most widely used gas transfer velocity parameterizations. Results show that net CO2 flux estimations during an entire seasonal cycle (September 2002–September 2003 may vary by a factor of ~ 3 depending on the selected wind speed product and the gas exchange parameterization, with the highest impact due to the last one. The comparison of satellite- and model-derived winds with observations at buoys advises against the systematic overestimation of NCEP-2 and the underestimation of NCEP-1. In the coastal region, the presence of land and the time resolution are the main constraints of QuikSCAT, which turns CCMP and ERA-Interim in the preferred options.

  11. Comparison of net CO2 fluxes measured with open- and closed-path infrared gas analyzers in an urban complex environment

    DEFF Research Database (Denmark)

    Järvi, L.; Mammarella, I.; Eugster, W.

    2009-01-01

    and their suitability to accurately measure CO2 exchange in such non-ideal landscape. In addition, this study examined the effect of open-path sensor heating on measured fluxes in urban terrain, and these results were compared with similar measurements made above a temperate beech forest in Denmark. The correlation...... between the two fluxes was good (R2 = 0.93) at the urban site, but during the measurement period the open-path net surface exchange (NSE) was 17% smaller than the closed-path NSE, indicating apparent additional uptake of CO2 by open-path measurements. At both sites, sensor heating corrections evidently...... improved the performance of the open-path analyzer by reducing discrepancies in NSE at the urban site to 2% and decreasing the difference in NSE from 67% to 7% at the forest site. Overall, the site-specific approach gave the best results at both sites and, if possible, it should be preferred in the sensor...

  12. Electronic portal imaging devices

    International Nuclear Information System (INIS)

    Lief, Eugene

    2008-01-01

    The topics discussed include, among others, the following: Role of portal imaging; Port films vs. EPID; Image guidance: Elekta volume view; Delivery verification; Automation tasks of portal imaging; Types of portal imaging (Fluorescent screen, mirror, and CCD camera-based imaging; Liquid ion chamber imaging; Amorpho-silicon portal imagers; Fluoroscopic portal imaging; Kodak CR reader; and Other types of portal imaging devices); QA of EPID; and Portal dosimetry (P.A.)

  13. Nitrogen Fertilization Effects on Net Ecosystem and Net Primary Productivities as Determined from Flux Tower, Biometric, and Model Estimates for a Coastal Douglas-fir Forest in British Columbia

    Science.gov (United States)

    Trofymow, J. A.; Metsaranta, J. M.; Black, T. A.; Jassal, R. S.; Filipescu, C.

    2013-12-01

    In coastal BC, 6,000-10,000 ha of public and significant areas of private forest land are annually fertilized with nitrogen, with or without thinning, to increase merchantable wood and reduce rotation age. Fertilization has also been viewed as a way to increase carbon (C) sequestration in forests and obtain C offsets. Such offset projects must demonstrate additionality with reference to a baseline and include monitoring to verify net C gains over the project period. Models in combination with field-plot measurements are currently the accepted methods for most C offset protocols. On eastern Vancouver Island, measurements of net ecosystem production (NEP), ecosystem respiration (Re) and gross primary productivity (GPP) using the eddy-covariance (EC) technique as well as component C fluxes and stocks have been made since 1998 in an intermediate-aged Douglas-fir dominated forest planted in 1949. In January 2007 an area around the EC flux tower was aerially fertilized with 200 kg urea-N ha-1. Ground plots in the fertilized area and an adjacent unfertilized control area were also monitored for soil (Rs) and heterotrophic (Rh) respiration, litterfall, and tree growth. To determine fertilization effects on whole tree growth, sample trees were felled in both areas for the 4-year (2003-06) pre- and the 4-year (2007-10) post-fertilization periods and were compared with EC NEP estimates and tree-ring based NEP estimates from Carbon Budget Model - Canadian Forest Sector (CBM-CFS3) for the same periods. Empirical equations using climate and C fluxes from 1998-2006 were derived to estimate what the EC fluxes would have been in 2007-10 for the fertilized area had it been unfertilized. Mean EC NEP for 2007-10 was 561 g C m2 y-1 , a 64% increase above pre-fertilization NEP (341 g C m2 y-1) or 28% increase above estimated unfertilized NEP (438 g C m2 y-1). Most of the increase was attributed to increased tree C uptake (i.e., GPP), with little change in Re. In 2007 fertilization

  14. Effect of abomasal infusion of oligofructose on portal-drained visceral ammonia and urea-nitrogen fluxes in lactating Holstein cows

    DEFF Research Database (Denmark)

    Røjen, Betina Amdisen; Larsen, Mogens; Kristensen, Niels Bastian

    2012-01-01

    by reduced NH3 input to hepatic urea-N synthesis caused by increased sequestration of NH3 in the hindgut and excretion in feces. Increasing the hindgut fermentation in lactating dairy cows by abomasal infusion of 1,500 g/d of oligofructose shifted some N excretion from the urine to feces and possibly reduced......The effects of abomasal infusion of oligofructose in lactating dairy cows on the relationship between hindgut fermentation and N metabolism, and its effects on NH3 absorption and transfer of blood urea-N across the portal-drained viscera versus ruminal epithelia were investigated. Nine lactating...... treatments. Eight sample sets of arterial, portal, hepatic, and ruminal vein blood, ruminal fluid, and urine were obtained at 0.5 h before the morning feeding and at 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, and 6.5 h after feeding. It was hypothesized that an increased supply of fermentable substrate to the hindgut...

  15. Water-saving ground cover rice production system reduces net greenhouse gas fluxes in an annual rice-based cropping system

    Science.gov (United States)

    Yao, Z.; Du, Y.; Tao, Y.; Zheng, X.; Liu, C.; Lin, S.; Butterbach-Bahl, K.

    2014-11-01

    To safeguard food security and preserve precious water resources, the technology of water-saving ground cover rice production system (GCRPS) is being increasingly adopted for rice cultivation. However, changes in soil water status and temperature under GCRPS may affect soil biogeochemical processes that control the biosphere-atmosphere exchanges of methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2). The overall goal of this study is to better understand how net ecosystem greenhouse gas exchanges (NEGE) and grain yields are affected by GCRPS in an annual rice-based cropping system. Our evaluation was based on measurements of the CH4 and N2O fluxes and soil heterotrophic respiration (CO2 emissions) over a complete year, and the estimated soil carbon sequestration intensity for six different fertilizer treatments for conventional paddy and GCRPS. The fertilizer treatments included urea application and no N fertilization for both conventional paddy (CUN and CNN) and GCRPS (GUN and GNN), and solely chicken manure (GCM) and combined urea and chicken manure applications (GUM) for GCRPS. Averaging across all the fertilizer treatments, GCRPS increased annual N2O emission and grain yield by 40 and 9%, respectively, and decreased annual CH4 emission by 69%, while GCRPS did not affect soil CO2 emissions relative to the conventional paddy. The annual direct emission factors of N2O were 4.01, 0.09 and 0.50% for GUN, GCM and GUM, respectively, and 1.52% for the conventional paddy (CUN). The annual soil carbon sequestration intensity under GCRPS was estimated to be an average of -1.33 Mg C ha-1 yr-1, which is approximately 44% higher than the conventional paddy. The annual NEGE were 10.80-11.02 Mg CO2-eq ha-1 yr-1 for the conventional paddy and 3.05-9.37 Mg CO2-eq ha-1 yr-1 for the GCRPS, suggesting the potential feasibility of GCRPS in reducing net greenhouse effects from rice cultivation. Using organic fertilizers for GCRPS considerably reduced annual emissions of CH4

  16. Effect of abomasal infusion of oligofructose on portal-drained visceral ammonia and urea-nitrogen fluxes in lactating Holstein cows.

    Science.gov (United States)

    Røjen, B A; Larsen, M; Kristensen, N B

    2012-12-01

    The effects of abomasal infusion of oligofructose in lactating dairy cows on the relationship between hindgut fermentation and N metabolism, and its effects on NH(3) absorption and transfer of blood urea-N across the portal-drained viscera versus ruminal epithelia were investigated. Nine lactating Holstein cows fitted with ruminal cannulas and permanent indwelling catheters in major splanchnic blood vessels were used in an unbalanced crossover design with 14-d periods. Treatments were continuous abomasal infusion of water or 1,500 g/d of oligofructose. The same basal diet was fed with both treatments. Eight sample sets of arterial, portal, hepatic, and ruminal vein blood, ruminal fluid, and urine were obtained at 0.5h before the morning feeding and at 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, and 6.5 h after feeding. It was hypothesized that an increased supply of fermentable substrate to the hindgut would increase the uptake of urea-N from blood to the hindgut at the expense of urea-N uptake to the forestomach. The study showed that abomasal oligofructose infusion decreased the total amount of urea-N transferred from the blood to the gut, NH(3) absorption, and arterial blood urea-N concentration. Subsequently, hepatic NH(3) uptake and urea-N production also decreased with oligofructose infusion. Additionally, urea-N concentration in milk and urinary N excretion decreased with oligofructose treatment. The oligofructose infusion did not affect ruminal NH(3) concentrations or any other ruminal variables, nor did it affect ruminal venous - arterial concentration differences for urea-N and NH(3). The oligofructose treatment did not affect milk yield, but did decrease apparent digestibility of OM, N, and starch. Nitrogen excreted in the feces was greater with the oligofructose infusion. In conclusion, the present data suggest that increased hindgut fermentation did not upregulate urea-N transfer to the hindgut at the expense of urea-N uptake by the rumen, and the observed reduction

  17. Carbon dioxide flux and net primary production of a boreal treed bog: Responses to warming and water-table-lowering simulations of climate change

    Science.gov (United States)

    Munir, T. M.; Perkins, M.; Kaing, E.; Strack, M.

    2015-02-01

    Midlatitude treed bogs represent significant carbon (C) stocks and are highly sensitive to global climate change. In a dry continental treed bog, we compared three sites: control, recent (1-3 years; experimental) and older drained (10-13 years), with water levels at 38, 74 and 120 cm below the surface, respectively. At each site we measured carbon dioxide (CO2) fluxes and estimated tree root respiration (Rr; across hummock-hollow microtopography of the forest floor) and net primary production (NPP) of trees during the growing seasons (May to October) of 2011-2013. The CO2-C balance was calculated by adding the net CO2 exchange of the forest floor (NEff-Rr) to the NPP of the trees. From cooler and wetter 2011 to the driest and the warmest 2013, the control site was a CO2-C sink of 92, 70 and 76 g m-2, the experimental site was a CO2-C source of 14, 57 and 135 g m-2, and the drained site was a progressively smaller source of 26, 23 and 13 g CO2-C m-2. The short-term drainage at the experimental site resulted in small changes in vegetation coverage and large net CO2 emissions at the microforms. In contrast, the longer-term drainage and deeper water level at the drained site resulted in the replacement of mosses with vascular plants (shrubs) on the hummocks and lichen in the hollows leading to the highest CO2 uptake at the drained hummocks and significant losses in the hollows. The tree NPP (including above- and below-ground growth and litter fall) in 2011 and 2012 was significantly higher at the drained site (92 and 83 g C m-2) than at the experimental (58 and 55 g C m-2) and control (52 and 46 g C m-2) sites. We also quantified the impact of climatic warming at all water table treatments by equipping additional plots with open-top chambers (OTCs) that caused a passive warming on average of ~ 1 °C and differential air warming of ~ 6 °C at midday full sun over the study years. Warming significantly enhanced shrub growth and the CO2 sink function of the drained

  18. Noncirrotisk intrahepatisk portal hypertension

    DEFF Research Database (Denmark)

    Dam Fialla, Annette; Havelund, Troels

    2007-01-01

    Non-cirrhotic intrahepatic portal hypertension is characterized by portal hypertension in the absence of liver cirrhosis or portal vein thrombosis. The disease is common in the East and rarely seen in the West. Two cases with oesophageal varices are described. The histopathology is heterogeneous...... but includes vascular lesions and portal fibrosis. Patient management follows the current recommendations for variceal bleeding....

  19. Interannual variations of net community production and air-sea CO2 flux from winter to spring in the western subarctic North Pacific

    International Nuclear Information System (INIS)

    Midorikawa, Takashi; Ogawa, Kan; Nemoto, Kazuhiro; Kamiya, Hitomi; Umeda, Takafumi; Hiraishi, Naotaka; Wada, Akira; Ishii, Masao

    2003-01-01

    The role of spring biological production for the air-sea CO 2 flux was quantified in the Western Subarctic Gyre (48 deg N, 165 deg E), where the vertical profile of temperature revealed the existence of a temperature minimum (Tmin) layer in the North Pacific. The vertical profiles of temperature, salinity, dissolved oxygen, nutrients and dissolved inorganic carbon, DIC, in the upper water column were significantly variable year by year in spring, 1996-2000. Correspondingly, surface seawater at this site in spring was supersaturated with CO 2 in 1997, 1999 and 2000, but was undersaturated in 1996 and 1998. The concentrations of DIC and nutrients in the winter mixed layer were estimated from those in the Tmin layer in spring with a correction for particle decomposition based on the apparent oxygen utilization. The net community production (NCP) and air-sea CO 2 flux from winter to spring were calculated from the vertically integrated deficits of DIC and nutrients in the upper water column between the two seasons. The calculation of the carbon budget indicated large interannual variations of NCP (0-13 mmol/m 2 /d) and CO 2 efflux (4-16 mmol/m 2 /d) for this period. The CO 2 efflux was generally low in the year when NCP was high. The close coupling between biological production and CO 2 efflux suggested the important role of the changes in the mixed-layer depth, as a key process controlling both processes, especially of the timing, so that a decrease in the mixed-layer depth could result in the activation of biological production. The early biological consumption of the surface DIC concentration could shorten the period for acting as a source for atmospheric CO 2 and depress the CO 2 efflux in the Western Subarctic Gyre from winter to spring in 1996 and 1998. On the contrary, in 1997, persistently deep vertical mixing until late spring could suppress the biological activity and give rise to long-lasting CO 2 efflux

  20. Automated Monitoring of Carbon Fluxes in a Northern Rocky Mountain Forest Indicates Above-Average Net Primary Productivity During the 2015 Western U.S. Drought

    Science.gov (United States)

    Stenzel, J.; Hudiburg, T. W.

    2016-12-01

    As global temperatures rise in the 21st century, "hotter" droughts will become more intense and persistent, particularly in areas which already experience seasonal drought. Because forests represent a large and persistent terrestrial carbon sink which has previously offset a significant proportion of anthropogenic carbon emissions, forest carbon cycle responses to drought have become a prominent research concern. However, robust mechanistic modeling of carbon balance responses to projected drought effects requires improved observation-driven representations of carbon cycle processes; many such component processes are rarely monitored in complex terrain, are modeled or unrepresented quantities at eddy covariance sites, or are monitored at course temporal scales that are not conducive to elucidating process responses at process time scales. In the present study, we demonstrate the use of newly available and affordable automated dendrometers for the estimation of intra-seasonal Net Primary Productivity (NPP) in a Northern Rocky Mountain conifer forest which is impacted by seasonal drought. Results from our pilot study suggest that NPP was restricted by mid-summer moisture deficit under the extraordinary 2015 Western U.S. drought, with greater than 90% off stand growth occurring prior to August. Examination of growth on an inter-annual scale, however, suggests that the study site experienced above-average NPP during this exceptionally hot year. Taken together, these findings indicate that intensifying mid-summer drought in regional forests has affected the timing but has not diminished the magnitude of this carbon flux. By employing automated instrumentation for the intra-annual assessment of NPP, we reveal that annual NPP in regional forests is largely determined before mid-summer and is therefore surprisingly resilient to intensities of seasonal drought that exceed normal conditions of the 20th century.

  1. Effect of decreasing dietary phosphorus supply on net recycling of inorganic phosphate in lactating dairy cows.

    Science.gov (United States)

    Puggaard, L; Kristensen, N B; Sehested, J

    2011-03-01

    Five ruminally cannulated lactating Holstein cows, fitted with permanent indwelling catheters in the mesenteric vein, hepatic vein, portal vein, and an artery were used to study intestinal absorption and net recycling of inorganic phosphate (P(i)) to the gastrointestinal tract. Treatments were low P (LP; 2.4 g of P/kg of DM) and high P (HP; 3.4 g of P/kg of DM). The dietary total P (tP) concentrations were obtained by replacing 0.50% calcium carbonate in the LP diet with 0.50% monocalcium phosphate in the HP diet. Diets were fed for 14 d and cows were sampled on d 14 in each period. Cows were fed restrictively, resulting in equal dry matter intakes as well as milk, fat, and protein yields between treatments. Net P(i) recycling (primarily salivary) was estimated as the difference between net portal plasma flux (net absorption of P(i)) and apparently digested tP (feed - fecal tP difference). Phosphorus intake, apparently digested tP, and fecal tP excretion decreased with LP. An effect of decreased tP intake on net portal plasma flux of P(i) could not be detected. However, despite numerically minute net fluxes across the liver, the net splanchnic flux of P(i) was less in LP compared with that in HP. Though arterial plasma P(i) concentration decreased, net P(i) recycling was not decreased when tP intake was decreased, and recycling of P(i) was maintained at the expense of deposition of P(i) in bones. Data are not consistent with salivary P(i) secretion being the primary regulator of P(i) homeostasis at low tP intakes. On the contrary, maintaining salivary P(i) recycling at low tP intakes indicates that rumen function was prioritized at the expense of bone P reserves. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. The effect of Arctic sea-ice extent on the absorbed (net solar flux at the surface, based on ISCCP-D2 cloud data for 1983–2007

    Directory of Open Access Journals (Sweden)

    C. Matsoukas

    2010-01-01

    Full Text Available We estimate the effect of the Arctic sea ice on the absorbed (net solar flux using a radiative transfer model. Ice and cloud input data to the model come from satellite observations, processed by the International Satellite Cloud Climatology Project (ISCCP and span the period July 1983–June 2007. The sea-ice effect on the solar radiation fluctuates seasonally with the solar flux and decreases interannually in synchronisation with the decreasing sea-ice extent. A disappearance of the Arctic ice cap during the sunlit period of the year would radically reduce the local albedo and cause an annually averaged 19.7 W m−2 increase in absorbed solar flux at the Arctic Ocean surface, or equivalently an annually averaged 0.55 W m−2 increase on the planetary scale. In the clear-sky scenario these numbers increase to 34.9 and 0.97 W m−2, respectively. A meltdown only in September, with all other months unaffected, increases the Arctic annually averaged solar absorption by 0.32 W m−2. We examined the net solar flux trends for the Arctic Ocean and found that the areas absorbing the solar flux more rapidly are the North Chukchi and Kara Seas, Baffin and Hudson Bays, and Davis Strait. The sensitivity of the Arctic absorbed solar flux on sea-ice extent and cloud amount was assessed. Although sea ice and cloud affect jointly the solar flux, we found little evidence of strong non-linearities.

  3. Idiopathic portal hypertension

    International Nuclear Information System (INIS)

    Han, Tae Kyun; Ryu, Dae Sik; Kim, Heung Chul; Hur, Hun; Eom, Kyeung Tae; Namkung, Sook; Park, Man Soo; Hwang, Woo Chul; Lee, Kwan Seop

    1996-01-01

    To describe the radiologic findings of idiopathic portal hypertension and to find the points of differentiation between idiopathic portal hypertension and liver cirrhosis. Four portograms in five patients who for four years had suffered from pathologically confirmed idiopathic portal hypertension were retrospectively analyzed and compared with a portogram obtained from a control subject with liver cirrhosis. Portographic finding s of idiopathic portal hypertension were paucity of medium-sized portal branches, irregular and obtuse-angled division of peripheral branches, abrupt interruption and an avascular area beneath the liver margin. A portogram of idiopathic portal hypertension may be useful in differentiation this and liver cirrhosis

  4. Rare Disease Video Portal

    OpenAIRE

    Sánchez Bocanegra, Carlos Luis

    2011-01-01

    Rare Disease Video Portal (RD Video) is a portal web where contains videos from Youtube including all details from 12 channels of Youtube. Rare Disease Video Portal (RD Video) es un portal web que contiene los vídeos de Youtube incluyendo todos los detalles de 12 canales de Youtube. Rare Disease Video Portal (RD Video) és un portal web que conté els vídeos de Youtube i que inclou tots els detalls de 12 Canals de Youtube.

  5. Creació d'un portal web cercador de feina

    OpenAIRE

    Gómez Mondragón, Sergi

    2012-01-01

    Projecte de fi de carrera d'un portal web cercador de feina realitzat amb .NET i utilitzant SQL com a repositori de dades. Proyecto de fin de carrera de un portal web buscador de empleo realizado con .NET y utilizando SQL como repositorio de datos.

  6. The Knowledge Portal

    Data.gov (United States)

    Office of Personnel Management — Information on various courses, as well as personal data of employees and training records from The Knowledge Portal (TKP), a web-based training portal used for the...

  7. Usability of Discovery Portals

    NARCIS (Netherlands)

    Bulens, J.D.; Vullings, L.A.E.; Houtkamp, J.M.; Vanmeulebrouk, B.

    2013-01-01

    As INSPIRE progresses to be implemented in the EU, many new discovery portals are built to facilitate finding spatial data. Currently the structure of the discovery portals is determined by the way spatial data experts like to work. However, we argue that the main target group for discovery portals

  8. Portals people, processes, technology

    CERN Document Server

    Cox, Andrew

    2006-01-01

    First applied to internet gateways such as Yahoo, the concept of the ""portal"" has evolved in a number of directions. How can information services best take advantage of internet portals to improve access to resources? This collection seeks answers to such questions, providing an overview of how portals are being used.

  9. Effect of decreasing dietary phosphorus supply on net recycling of inorganic phosphate in lactating dairy cows

    DEFF Research Database (Denmark)

    Puggaard, Liselotte; Kristensen, Niels Bastian; Sehested, Jens Jakob

    2011-01-01

    (LP; 2.4 g of P/kg of DM) and high P (HP; 3.4 g of P/kg of DM). The dietary total P (tP) concentrations were obtained by replacing 0.50% calcium carbonate in the LP diet with 0.50% monocalcium phosphate in the HP diet. Diets were fed for 14 d and cows were sampled on d 14 in each period. Cows were fed...... restrictively, resulting in equal dry matter intakes as well as milk, fat, and protein yields between treatments. Net Pi recycling (primarily salivary) was estimated as the difference between net portal plasma flux (net absorption of Pi) and apparently digested tP (feed – fecal tP difference). Phosphorus intake...

  10. Portal hypertensiv gastropati

    DEFF Research Database (Denmark)

    Brinch, K; Møller, S; Henriksen, Jens Henrik Sahl

    1995-01-01

    Portal hypertensive gastropathy (PHG) as defined by congestive changes in the gastric mucosa owing to increased portal pressure, was first described about ten years ago. Whereas definition and grading of severity are still under debate, there is general agreement that PHG is a new clinical entity....... PHG is present in 50-80% of patients with liver cirrhosis. PHG is a major cause of upper gastrointestinal bleeding in patients with portal hypertension (25-90% depending on severity). Presence of portal hypertension is a prerequisite for the development of PHG, and reduction of portal pressure...

  11. Mobile Portal Implementation Strategy

    DEFF Research Database (Denmark)

    Gao, Ping; Damsgaard, Jan

    2005-01-01

    Mobile portal plays an important role in mobile commerce market. Current literature focuses on static analysis on the value chain of mobile portals. This article provides a dynamic perspective on mobile portal strategy. Drawing upon network economics, we describe mobile portal implementation...... as a fourphase process. In different phase, a portal provider has various challenges to overcome and adopt diverse strategies, and correspondingly the regulator has different foci. The conceptual framework proposed in this article offers a basis for further analyses on the market dynamics of mobile commerce......, and can be generalized to studying other networked technologies...

  12. Reduced uncertainty of regional scale CLM predictions of net carbon fluxes and leaf area indices with estimated plant-specific parameters

    Science.gov (United States)

    Post, Hanna; Hendricks Franssen, Harrie-Jan; Han, Xujun; Baatz, Roland; Montzka, Carsten; Schmidt, Marius; Vereecken, Harry

    2016-04-01

    Reliable estimates of carbon fluxes and states at regional scales are required to reduce uncertainties in regional carbon balance estimates and to support decision making in environmental politics. In this work the Community Land Model version 4.5 (CLM4.5-BGC) was applied at a high spatial resolution (1 km2) for the Rur catchment in western Germany. In order to improve the model-data consistency of net ecosystem exchange (NEE) and leaf area index (LAI) for this study area, five plant functional type (PFT)-specific CLM4.5-BGC parameters were estimated with time series of half-hourly NEE data for one year in 2011/2012, using the DiffeRential Evolution Adaptive Metropolis (DREAM) algorithm, a Markov Chain Monte Carlo (MCMC) approach. The parameters were estimated separately for four different plant functional types (needleleaf evergreen temperate tree, broadleaf deciduous temperate tree, C3-grass and C3-crop) at four different sites. The four sites are located inside or close to the Rur catchment. We evaluated modeled NEE for one year in 2012/2013 with NEE measured at seven eddy covariance sites in the catchment, including the four parameter estimation sites. Modeled LAI was evaluated by means of LAI derived from remotely sensed RapidEye images of about 18 days in 2011/2012. Performance indices were based on a comparison between measurements and (i) a reference run with CLM default parameters, and (ii) a 60 instance CLM ensemble with parameters sampled from the DREAM posterior probability density functions (pdfs). The difference between the observed and simulated NEE sum reduced 23% if estimated parameters instead of default parameters were used as input. The mean absolute difference between modeled and measured LAI was reduced by 59% on average. Simulated LAI was not only improved in terms of the absolute value but in some cases also in terms of the timing (beginning of vegetation onset), which was directly related to a substantial improvement of the NEE estimates in

  13. Noncirrhotic portal hypertension.

    Science.gov (United States)

    Da, Ben L; Koh, Christopher; Heller, Theo

    2018-05-01

    Noncirrhotic portal hypertension represents a heterogeneous group of liver disorders that is characterized by portal hypertension in the absence of cirrhosis. The purpose of this review is to serve as a guide on how to approach a patient with noncirrhotic portal hypertension with a focus on recent developments. Recent studies pertaining to noncirrhotic portal hypertension have investigated aetiological causes, mechanisms of disease, noninvasive diagnostic modalities, clinical characteristics in the paediatric population and novel treatment targets. Noncirrhotic portal hypertension is an underappreciated clinical entity that can be difficult to diagnosis without a healthy suspicion. Diagnosis then relies on a comprehensive understanding of the causes and clinical manifestations of this disease, as well as a careful interpretation of the liver biopsy. Noninvasive approaches to diagnosis may play a significant role moving forward in this disease. Treatment in NCPH remains largely targeted at the individual sequalae of portal hypertension.

  14. Hepatic angiography: Portal hypertension

    International Nuclear Information System (INIS)

    Oliver, T.W. Jr.; Sones, P.J. Jr.

    1985-01-01

    Portal hypertension is usually a manifestation of underlying hepatic parenchymal disease, although it may be secondary to portal or hepatic venous thrombosis and rarely to hyperdynamic portal states. Portal hypertension may present as encephalopathy, ascites, jaundice, hepatic failure, or catastrophic upper gastrointestinal hemorrhage. Radiologic investigation should include indirect or direct measurements of portal pressure, assessment of portal venous perfusion, visualization of collaterals, and demonstration of arterial and venous anatomy for potential shunt procedure. Following survival of initial variceal bleeding, the most effective procedure to prevent recurrent hemorrhage is a shunt to decompress the varices. The decision whether to intervene medically or surgically during the acute hemorrhagic episode as well as the type of shunt used to prevent future hemorrhage is the subject of continuing controversy

  15. Pediatric portal hypertension

    Science.gov (United States)

    Vogel, Clarissa Barbon

    2017-01-01

    Abstract: Pediatric portal hypertension management is a team approach between the patient, the patient's family, the primary caregiver, and specialty providers. Evidence-based practice guidelines have not been established in pediatrics. This article serves as a review for the primary care NP in the management of pediatric portal hypertension, discussing the etiology, pathophysiology, and clinical presentation of pediatric portal hypertension, diagnostic tests, and treatment and management options. PMID:28406835

  16. Usability of Discovery Portals

    OpenAIRE

    Bulens, J.D.; Vullings, L.A.E.; Houtkamp, J.M.; Vanmeulebrouk, B.

    2013-01-01

    As INSPIRE progresses to be implemented in the EU, many new discovery portals are built to facilitate finding spatial data. Currently the structure of the discovery portals is determined by the way spatial data experts like to work. However, we argue that the main target group for discovery portals are not spatial data experts but professionals with limited spatial knowledge, and a focus outside the spatial domain. An exploratory usability experiment was carried out in which three discovery p...

  17. Interaction of environmental calcium and low pH on the physiology of the rainbow trout, Salmo gairdneri. I. Branchial and renal net ion and H/sup +/ fluxes

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, D.G.

    1983-01-01

    Exposure of adult rainbow trout to low pH (pH 4.3) in soft water (Ca/sup 2 +/ = 223 ..mu..equiv/1) caused a substantial ionic disturbance which arose primarily because of large net losses at the gills. In contrast, renal ion losses were low initially and declined even further because of a pronounced reduction in urine flow. A net influx of H/sup +/ occurred across the gills but this was not sufficient to cause a blood acid-base disturbance or a renal response. Although branchial ion and H/sup +/ fluxes declined with time, blood ion levels did not return to normal and many of the fish died. Further reduction in water calcium (Ca/sup 2 +/ = 69 ..mu..equiv/1) provoked a higher mortality and a more substantial ionic imbalance. These results contrast sharply with the effects on trout of acid exposure in hard water (Ca/sup 2 +/ greater than or equal to 1600 ..mu..equiv/1), where net ion losses and mortality are reduced and H/sup +/ uptake increased. A preliminary model for the interaction of low pH and calcium is proposed and evidence for adaptation to acid stress and for the origin of acid lethality is discussed. 46 references, 5 figures, 3 tables.

  18. Petri Nets

    Indian Academy of Sciences (India)

    In a computer system, for example, typical discrete events ... This project brought out a series of influential reports on Petri net theory in the mid and late ... Technology became a leading centre for Petri net research and from then on, Petri nets ...

  19. Portal cholangiopathy: case report

    Directory of Open Access Journals (Sweden)

    Maria Cecilia Almeida Maia

    2014-01-01

    Full Text Available The present report describes the case of a child that after blunt abdominal trauma presented with portal thrombosis followed by progressive splenomegaly and jaundice. Ultrasonography and percutaneous cholangiography revealed biliary dilatation secondary to choledochal stenosis caused by dilated peribiliary veins, characterizing a case of portal biliopathy. The present case report is aimed at presenting an uncommon cause of this condition.

  20. Roadside Tracker Portal-less Portal Monitor

    Energy Technology Data Exchange (ETDEWEB)

    Ziock, Klaus-Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cheriyadat, Anil M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bradley, Eric Craig [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cunningham, Mark F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Fabris, Lorenzo [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Goddard, Jr, James Samuel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hornback, Donald Eric [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Karnowski, Thomas Paul [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kerekes, Ryan A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Newby, Jason [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2013-07-01

    This report documents the full development cycle of the Roadside Tracker (RST) Portal-less Portal monitor (Fig. 1) funded by DHS DNDO. The project started with development of a proof-of-feasibility proto-type, proceeded through design and construction of a proof-of-concept (POC) prototype, a test-and-evaluation phase, participation in a Limited Use Exercise that included the Standoff Radiation Detections Systems developed under an Advanced Technology Demonstration and concluded with participation in a Characterization Study conducted by DNDO.

  1. The XCAT Science Portal

    Directory of Open Access Journals (Sweden)

    Sriram Krishnan

    2002-01-01

    Full Text Available This paper describes the design and prototype implementation of the XCAT Grid Science Portal. The portal lets grid application programmers script complex distributed computations and package these applications with simple interfaces for others to use. Each application is packaged as a notebook which consists of web pages and editable parameterized scripts. The portal is a workstation-based specialized personal web server, capable of executing the application scripts and launching remote grid applications for the user. The portal server can receive event streams published by the application and grid resource information published by Network Weather Service (NWS [35] or Autopilot [16] sensors. Notebooks can be published and stored in web based archives for others to retrieve and modify. The XCAT Grid Science Portal has been tested with various applications, including the distributed simulation of chemical processes in semiconductor manufacturing and collaboratory support for X-ray crystallographers.

  2. Portal Vein Stenting for Portal Biliopathy with Jaundice

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, Dongho, E-mail: mesentery@naver.com; Park, Kwang Bo, E-mail: kbjh.park@samsung.com [Sungkyunkwan University School of Medicine, Department of Radiology, Samsung Medical Center (Korea, Republic of); Lim, Seong Joo [Konyang University, Department of Radiology, College of Medicine, Konyang University Hospital (Korea, Republic of); Hwang, Jin Ho [Hallym University Sacred Heart Hospital, Department of Radiology (Korea, Republic of); Sinn, Dong Hyun [Sungkyunkwan University School of Medicine, Department of Medicine, Samsung Medical Center (Korea, Republic of)

    2016-04-15

    Portal biliopathy refers to obstruction of the bile duct by dilated peri- or para-ductal collateral channels following the main portal vein occlusion from various causes. Surgical shunt operation or endoscopic treatment has been reported. Herein, we report a case of portal biliopathy that was successfully treated by interventional portal vein recanalization.

  3. Portal vein thrombosis.

    Science.gov (United States)

    Chawla, Yogesh K; Bodh, Vijay

    2015-03-01

    Portal vein thrombosis is an important cause of portal hypertension. PVT occurs in association with cirrhosis or as a result of malignant invasion by hepatocellular carcinoma or even in the absence of associated liver disease. With the current research into its genesis, majority now have an underlying prothrombotic state detectable. Endothelial activation and stagnant portal blood flow also contribute to formation of the thrombus. Acute non-cirrhotic PVT, chronic PVT (EHPVO), and portal vein thrombosis in cirrhosis are the three main variants of portal vein thrombosis with varying etiological factors and variability in presentation and management. Procoagulant state should be actively investigated. Anticoagulation is the mainstay of therapy for acute non-cirrhotic PVT, with supporting evidence for its use in cirrhotic population as well. Chronic PVT (EHPVO) on the other hand requires the management of portal hypertension as such and with role for anticoagulation in the setting of underlying prothrombotic state, however data is awaited in those with no underlying prothrombotic states. TIPS and liver transplant may be feasible even in the setting of PVT however proper selection of candidates and type of surgery is warranted. Thrombolysis and thrombectomy have some role. TARE is a new modality for management of HCC with portal vein invasion.

  4. Radiation portal evaluation parameters

    International Nuclear Information System (INIS)

    York, R.L.

    1998-01-01

    The detection of the unauthorized movement of radioactive materials is one of the most effective nonproliferation measures. Automatic special nuclear material (SNM) portal monitors are designed to detect this unauthorized movement and are an important part of the safeguard systems at US nuclear facilities. SNM portals differ from contamination monitors because they are designed to have high sensitivity for the low energy gamma-rays associated with highly enriched uranium (HEU) and plutonium. These instruments are now being installed at international borders to prevent the spread of radioactive contamination an SNM. In this paper the parameters important to evaluating radiation portal monitors are discussed. (author)

  5. A chess web portal

    OpenAIRE

    Volf, Žiga

    2011-01-01

    The aim of the thesis was to develop a web portal for chess players, which is intended to be a place for quality chess joining over the Internet and chess education. This need is caused by existing social networks and websites for playing chess, which offer you a very small amount of quality chess joining and education. As a result of the work the chess portal was created. We have presented the development of the chess portal in the thesis, which has all the features the chess players are i...

  6. Influence of changes in wetland inundation extent on net fluxes of carbon dioxide and methane in northern high latitudes from 1993 to 2004

    International Nuclear Information System (INIS)

    Zhuang, Qianlai; Zhu, Xudong; He, Yujie; Prigent, Catherine; Melillo, Jerry M; Kicklighter, David W; David McGuire, A; Prinn, Ronald G

    2015-01-01

    Estimates of the seasonal and interannual exchanges of carbon dioxide (CO 2 ) and methane (CH 4 ) between land ecosystems north of 45°N and the atmosphere are poorly constrained, in part, because of uncertainty in the temporal variability of water-inundated land area. Here we apply a process-based biogeochemistry model to evaluate how interannual changes in wetland inundation extent might have influenced the overall carbon dynamics of the region during the time period 1993–2004. We find that consideration by our model of these interannual variations between 1993 and 2004, on average, results in regional estimates of net methane sources of 67.8 ± 6.2 Tg CH 4 yr −1 , which is intermediate to model estimates that use two static inundation extent datasets (51.3 ± 2.6 and 73.0 ± 3.6 Tg CH 4 yr −1 ). In contrast, consideration of interannual changes of wetland inundation extent result in regional estimates of the net CO 2 sink of −1.28 ± 0.03 Pg C yr −1 with a persistent wetland carbon sink from −0.38 to −0.41 Pg C yr −1 and a upland sink from −0.82 to −0.98 Pg C yr −1 . Taken together, despite the large methane emissions from wetlands, the region is a consistent greenhouse gas sink per global warming potential (GWP) calculations irrespective of the type of wetland datasets being used. However, the use of satellite-detected wetland inundation extent estimates a smaller regional GWP sink than that estimated using static wetland datasets. Our sensitivity analysis indicates that if wetland inundation extent increases or decreases by 10% in each wetland grid cell, the regional source of methane increases 13% or decreases 12%, respectively. In contrast, the regional CO 2 sink responds with only 7–9% changes to the changes in wetland inundation extent. Seasonally, the inundated area changes result in higher summer CH 4 emissions, but lower summer CO 2 sinks, leading to lower summer negative greenhouse gas forcing. Our analysis further

  7. ASKME Enterprise Portal (internal) -

    Data.gov (United States)

    Department of Transportation — The ASKME Enterprise Portal Internal (AEPi) is envisioned to be an integrated, single-point-of-entry solution that contains modular components. The AEPi will provide...

  8. Liferay Portal Systems Development

    CERN Document Server

    Yuan, Jonas X

    2012-01-01

    This book focuses on teaching by example. Every chapter provides an overview, and then dives right into hands-on examples so you can see and play with the solution in your own environment. This book is for Java developers who don't need any prior experience with Liferay portal. Although Liferay portal makes heavy use of open source frameworks, no prior experience of using these is assumed.

  9. ELECTRONIC COMMERCE PORTAL

    OpenAIRE

    Georgeta Soava

    2011-01-01

    Today companies are faced with the need to exploit technology changing computer environments, in order to improve customer satisfaction and reduce costs. A successful approach to electronic portals is an effective demonstration of the new ways of relating to the client. The objectives that we have considered for the realization of e-commerce portal can be summarized as follows: structured communication, effective collaboration, complet and closed circuit of orders and deliveries, inventory op...

  10. Net Neutrality

    DEFF Research Database (Denmark)

    Savin, Andrej

    2017-01-01

    Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else.......Repealing “net neutrality” in the US will have no bearing on Internet freedom or security there or anywhere else....

  11. Biology of portal hypertension.

    Science.gov (United States)

    McConnell, Matthew; Iwakiri, Yasuko

    2018-02-01

    Portal hypertension develops as a result of increased intrahepatic vascular resistance often caused by chronic liver disease that leads to structural distortion by fibrosis, microvascular thrombosis, dysfunction of liver sinusoidal endothelial cells (LSECs), and hepatic stellate cell (HSC) activation. While the basic mechanisms of LSEC and HSC dysregulation have been extensively studied, the role of microvascular thrombosis and platelet function in the pathogenesis of portal hypertension remains to be clearly characterized. As a secondary event, portal hypertension results in splanchnic and systemic arterial vasodilation, leading to the development of a hyperdynamic circulatory syndrome and subsequently to clinically devastating complications including gastroesophageal varices and variceal hemorrhage, hepatic encephalopathy from the formation of portosystemic shunts, ascites, and renal failure due to the hepatorenal syndrome. This review article discusses: (1) mechanisms of sinusoidal portal hypertension, focusing on HSC and LSEC biology, pathological angiogenesis, and the role of microvascular thrombosis and platelets, (2) the mesenteric vasculature in portal hypertension, and (3) future directions for vascular biology research in portal hypertension.

  12. On line portal imaging

    International Nuclear Information System (INIS)

    Munro, Peter

    1996-01-01

    Purpose/Objective: The purpose of this presentation is to examine the various imaging devices that have been developed for portal imaging; describe some of the image registration methods that have been developed to determine geometric errors quantitatively; discuss some of the ways that portal imaging has been incorporated into routine clinical practice; describe quality assurance procedures for these devices, and discuss the use of portal imaging devices for dosimetry applications. Discussion: Verification of patient positioning has always been an important aspect of external beam radiation therapy. Over the past decade many portal imaging devices have been developed by individual investigators and most accelerator manufacturers now offer 'on-line' portal imaging systems. The commercial devices can be classified into three categories: T.V. camera-based systems, liquid ionisation chamber systems, and amorphous silicon systems. Many factors influence the quality of images generated by these portal imaging systems. These include factors which are unavoidable (e.g., low subject contrast), factors which depend upon the individual imaging device forming the image (e.g., dose utilisation, spatial resolution) as well as factors which depend upon the characteristics of the linear accelerator irradiating the imaging system (x-ray source size, image magnification). The characteristics of individual imaging systems, such as spatial resolution, temporal response, and quantum utilisation will be discussed. One of the major advantages of on-line portal imaging is that many quantitative techniques have been developed to detect errors in patient positioning. The general approach is to register anatomic structures on a portal image with the same structures on a digitized simulator film. Once the anatomic structures have been registered, any discrepancies in the position of the patient can be identified. However, the task is not nearly as straight-forward as it sounds. One problem

  13. Extrahepatic portal hypertension in childhood

    International Nuclear Information System (INIS)

    Takehara, Hiroo; Komi, Nobuhiko; Goh, Masahiro; Yoshida, Sadahiro; Kameoka, Kazuhiro; Hino, Masao; Sui, Osamu

    1986-01-01

    Four pediatric patients with extrahepatic portal hypertension had undergone portography and computerized radionuclide angiography in order to examine shape of portal system and to evaluate hepatic blood flow before and aftersurgical treatment. In all patients, cavernous transformation of portal system was demonstrated by portography, and in one of them spontaneous splenorenal shunt occurred. In 3 of them, who underwent esophageal transsection combined with paraesophagogastric devascularization and splenectomy, so-called direct operation, increase of portal blood flow was revealed by computerized radionuclide angiography. It is suggested that direct operation increasing portal blood flow after surgery is effective in treating extrahepatic portal hypertension in childhood. (author)

  14. On line portal imaging

    International Nuclear Information System (INIS)

    Munro, Peter

    1997-01-01

    Purpose/Objective: The purpose of this presentation is to examine the various imaging devices that have been developed for portal imaging, describe some of the image registration methods that have been developed to determine geometric errors quantitatively, and discuss how portal imaging has been incorporated into clinical practice. Discussion: Verification of patient positioning has always been an important aspect of external beam radiation therapy. Over the past decade many portal imaging devices have been developed by individual investigators and most accelerator manufacturers now offer 'on-line' portal imaging systems. The commercial devices include T.V. camera-based systems, liquid ionisation chamber systems, and shortly, flat panel systems. The characteristics of these imaging systems will be discussed. In addition, other approaches such as the use of kilovoltage x-ray sources, video monitoring, and ultrasound have been proposed for improving patient positioning. Some of the advantages of these approaches will be discussed. One of the major advantages of on-line portal imaging is that many quantitative techniques have been developed to detect errors in patient positioning. The general approach is to register anatomic structures on a portal image with the same structures on a digitized simulator film. Once the anatomic structures have been registered, any discrepancies in the position of the patient can be identified. One problem is finding a common frame of reference for the simulator and portal images, since the location of the radiation field within the pixel matrix may differ for the two images. As a result, a common frame of reference has to be established before the anatomic structures in the images can be registered - generally by registering radiation field edges identified in the simulator and portal images. In addition, distortions in patient geometry or rotations out of the image plane can confound the image registration techniques. Despite the

  15. Petri Nets

    Indian Academy of Sciences (India)

    GENERAL I ARTICLE ... In Part 1 of this two-part article, we have seen im- ..... mable logic controller and VLSI arrays, office automation systems, workflow management systems, ... complex discrete event and real-time systems; and Petri nets.

  16. Portal venous stent placement for treatment of portal hypertension caused by benign main portal vein stenosis.

    Science.gov (United States)

    Shan, Hong; Xiao, Xiang-Sheng; Huang, Ming-Sheng; Ouyang, Qiang; Jiang, Zai-Bo

    2005-06-07

    To evaluate the value of endovascular stent in the treatment of portal hypertension caused by benign main portal vein stenosis. Portal vein stents were implanted in six patients with benign main portal vein stenosis (inflammatory stenosis in three cases, postprocedure of liver transplantation in another three cases). Changes in portal vein pressure, portal vein patency, relative clinical symptoms, complications, and survival were evaluated. Six metallic stents were successfully placed across the portal vein stenotic or obstructive lesions in six patients. Mean portal venous pressure decreased significantly after stent implantation from (37.3+/-4.7) cm H(2)O to (18.0+/-1.9) cm H(2)O. The portal blood flow restored and the symptoms caused by portal hypertension were eliminated. There were no severe procedure-related complications. The patients were followed up for 1-48 mo. The portal vein remained patent during follow-up. All patients survived except for one patient who died of other complications of liver transplantation. Percutaneous portal vein stent placement for the treatment of portal hypertension caused by benign main portal vein stenosis is safe and effective.

  17. Pregnancy with Portal Hypertension

    Science.gov (United States)

    Aggarwal, Neelam; Negi, Neha; Aggarwal, Aakash; Bodh, Vijay; Dhiman, Radha K.

    2014-01-01

    Even though pregnancy is rare with cirrhosis and advanced liver disease, but it may co-exist in the setting of non-cirrhotic portal hypertension as liver function is preserved but whenever encountered together is a complex clinical dilemma. Pregnancy in a patient with portal hypertension presents a special challenge to the obstetrician as so-called physiological hemodynamic changes associated with pregnancy, needed for meeting demands of the growing fetus, worsen the portal hypertension thereby putting mother at risk of potentially life-threatening complications like variceal hemorrhage. Risks of variceal bleed and hepatic decompensation increase many fold during pregnancy. Optimal management revolves round managing the portal hypertension and its complications. Thus management of such cases requires multi-speciality approach involving obstetricians experienced in dealing with high risk cases, hepatologists, anesthetists and neonatologists. With advancement in medical field, pregnancy is not contra-indicated in these women, as was previously believed. This article focuses on the different aspects of pregnancy with portal hypertension with special emphasis on specific cause wise treatment options to decrease the variceal bleed and hepatic decompensation. Based on extensive review of literature, management from pre-conceptional period to postpartum is outlined in order to have optimal maternal and perinatal outcomes. PMID:25755552

  18. The NOAO NVO Portal

    Science.gov (United States)

    Miller, C. J.; Gasson, D.; Fuentes, E.

    2007-10-01

    The NOAO NVO Portal is a web application for one-stop discovery, analysis, and access to VO-compliant imaging data and services. The current release allows for GUI-based discovery of nearly a half million images from archives such as the NOAO Science Archive, the Hubble Space Telescope WFPC2 and ACS instruments, XMM-Newton, Chandra, and ESO's INT Wide-Field Survey, among others. The NOAO Portal allows users to view image metadata, footprint wire-frames, FITS image previews, and provides one-click access to science quality imaging data throughout the entire sky via the Firefox web browser (i.e., no applet or code to download). Users can stage images from multiple archives at the NOAO NVO Portal for quick and easy bulk downloads. The NOAO NVO Portal also provides simplified and direct access to VO analysis services, such as the WESIX catalog generation service. We highlight the features of the NOAO NVO Portal (http://nvo.noao.edu).

  19. Radioisotopic flow scanning for portal blood flow and portal hypertension

    International Nuclear Information System (INIS)

    Hesdorffer, C.S.; Bezwoda, W.R.; Danilewitz, M.D.; Esser, J.D.; Tobias, M.

    1987-01-01

    The use of a simple, noninvasive, isotope scanning technique for the determination of relative portal blood flow and detection of portal hypertension is described. Using this technique the presence of portal hypertension was demonstrated in seven of nine patients known to have elevated portal venous pressure. By contrast, esophageal varices were demonstrated in only five of these patients, illustrating the potential value of the method. Furthermore, this technique has been adapted to the study of portal blood flow in patients with myeloproliferative disorders with splenomegaly but without disturbances in hepatic architecture. Results demonstrate that the high relative splenic flow resulting from the presence of splenomegaly may in turn be associated with elevated relative portal blood flow and portal hypertension. The theoretic reasons for the development of flow-related portal hypertension and its relationship to splenic blood flow are discussed

  20. Adaptations of hepatic amino acid uptake and net utilisation contributes to nitrogen economy or waste in lambs fed nitrogen- or energy-deficient diets.

    Science.gov (United States)

    Kraft, G; Ortigues-Marty, I; Durand, D; Rémond, D; Jardé, T; Bequette, B; Savary-Auzeloux, I

    2011-04-01

    We investigated the effect of relative changes in dietary nitrogen (N) and energy supply and the subsequent variations in net portal appearance (NPA) of nitrogenous and energy nutrients on the net amino acid (AA) uptake by the liver and net N supply to the peripheral tissues. Six lambs were catheterised across the splanchnic tissues and received, in a replicated Latin square, one of three dietary treatments. The diets were formulated to either match the requirements of N and energy (C), or supply only 0.8 of the N requirement (LN) or 0.8 of the energy requirement (LE). Net fluxes of AA and urea-N were measured across the portal-drained viscera, and estimation of arterial hepatic flow allowed the estimation of hepatic fluxes. Catheters were implanted into the portal and hepatic veins as well as in the abdominal aorta for the measurement of AA fluxes. Animals fed the LN diet showed more efficient N retention (0.59 of digested N) than did the C and LE diet (0.50 and 0.33, respectively; P < 0.001). The NPA of total AA-N for the LN diet was only 0.60 of the value measured for the control (C) diet (P < 0.01). Despite this, the total estimated AA-N net splanchnic fluxes were not significantly different across the three diets (3.3, 1.9 and 2.6 g total AA-N/day for C, LN and LE, respectively, P = 0.52). Thus, different metabolic regulations must have taken place across the liver between the three experimental diets. A combination of decreased net uptake of total AA-N by the liver of animals in the LN diet (0.61 of the C diet; P = 0.002) and reduced urinary urea-N production (0.52 of the C diet; P = 0.001) spared AA from catabolism in the LN diet relative to the other two diets. For the LE diet, the urinary urea-N output was 1.3 times the value of the C diet (P = 0.01). This may relate to an increased catabolism of AA by the muscle and/or, to a lesser extent, to an increased utilisation of AA for gluconeogenesis in the liver. These effects may explain the reduced whole body

  1. NEON's Eddy-Covariance Storage Exchange: from Tower to Data Portal

    Science.gov (United States)

    Durden, N. P.; Luo, H.; Xu, K.; Metzger, S.; Durden, D.

    2017-12-01

    NEON's eddy-covariance storage exchange system (ECSE) consists of a suite of sensors including temperature sensors, a CO2 and H2O gas analyzer, and isotopic CO2 and H2O analyzers. NEON's ECSE was developed to provide the vertical profile measurements of temperature, CO2 and H2O concentrations, the stable isotope ratios in CO2 (δ13C) and H2O (δ18O and δ2H) in the atmosphere. The profiles of temperature and concentrations of CO2 and H2O are key to calculate storage fluxes for eddy-covariance tower sites. Storage fluxes have a strong diurnal cycle and can be large in magnitude, especially at temporal scales less than one day. However, the storage term is often neglected in flux computations. To obtian accurate eddy-covariance fluxes, the storage fluxes are calculated and incorporated into the calculations of net surface-atmosphere ecosystem exchange of heat, CO2, and H2O for each NEON tower site. Once the ECSE raw data (Level 0, or L0) is retrieved at NEON's headquarters, it is preconditioned through a sequence of unit conversion, time regularization, and plausibility tests. By utilizing NEON's eddy4R framework (Metzger et al., 2017), higher-level data products are generated including: Level 1 (L1): Measurement-level specific averages of temperature and concentrations of CO2 and H2O. Level 2 (L2): Time rate of change of temperature and concentrations of CO2 and H2O over 30 min at each measurement level along the vertical tower profile. Level 3 (L3): Time rate of change of temperature and concentrations of CO2 and H2O over 30 min (L2), spatially interpolated along the vertical tower profile. Level 4 (L4): Storage fluxes of heat, CO2, and H2O calculated from the integrated time rate of change spatially interpolated profile (L3). The L4 storage fluxes are combined with turbulent fluxes to calculate the net surface-atmosphere ecosystem exchange of heat, CO2, and H2O. Moreover, a final quality flag and uncertainty budget are produced individually for each data stream

  2. Personalization Methods for Internet Portals

    OpenAIRE

    Barbara Dębska; Agnieszka Kubacka

    2012-01-01

    The article presents methods of acquiring and gathering data about users of internet portals, with particular emphasis on educational portals. Definitions, aims and tasks related to the process of personalization of e-learning portals are thoroughly discussed. So are knowledge acquisition techniques applied in personalization, especially artificial intelligence methods.

  3. RESTful NET

    CERN Document Server

    Flanders, Jon

    2008-01-01

    RESTful .NET is the first book that teaches Windows developers to build RESTful web services using the latest Microsoft tools. Written by Windows Communication Foundation (WFC) expert Jon Flanders, this hands-on tutorial demonstrates how you can use WCF and other components of the .NET 3.5 Framework to build, deploy and use REST-based web services in a variety of application scenarios. RESTful architecture offers a simpler approach to building web services than SOAP, SOA, and the cumbersome WS- stack. And WCF has proven to be a flexible technology for building distributed systems not necessa

  4. Improved netting

    International Nuclear Information System (INIS)

    Bramley, A.; Clabburn, R.J.T.

    1976-01-01

    A method is described for producing netting composed of longitudinal and transverse threads of irradiation cross linked thermoplastic material, the threads being joined together at their crossings by moulded masses of cross linked thermoplastic material. The thread may be formed of polyethylene filaments, subjected to a radiation dose of 15 to 25 MR. The moulding can be conducted at 245 0 to 260 0 C or higher. The product is claimed to be an improved quality of netting, with bonds of increased strength between crossing threads. (U.K.)

  5. The Learning Portal

    Science.gov (United States)

    Staudt, Carolyn; Hanzlick-Burton, Camden; Williamson, Carol; McIntyre, Cynthia

    2015-01-01

    The Innovative Technology in Science Inquiry (ITSI) project is a learning portal with hundreds of free, customizable science, math, and engineering activities funded by the National Science Foundation at the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology. The project…

  6. BRAZILIAN NEWS PORTALS CHARACTERISTICS

    Directory of Open Access Journals (Sweden)

    Heloiza G. Herckovitz

    2011-02-01

    Full Text Available A content analysis of four Brazilian news media portals found that economic news dominated the top headlines with little attention paid to education, the environment and welfare. Other trends included a focus on local events and national news sources, reliance on few sources, mostly official ones, and a low percentage of news that fitted the concept of newsworthiness (a combination of both social significance and deviance concepts. Other findings of a study of 432 top news stories published by UOL, Estadão, iG and Terra during a 15-day period between February and March 2008 indicate that the top portions of the portals’ front pages carry news that lacks story depth, editorial branding, and multimedia applications. The results suggest that online news portals are in their infancy although Brazil has the largest online population of Latin America. This study hopes to shed light on the gatekeeping process in Brazilian news portals. Brazilian media portals have yet to become a significant editorial force able to provide knowledge about social issues and public affairs in a socially responsible fashione.

  7. Petri Nets

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 4; Issue 9. Petri Nets - Applications. Y Narahari. General Article Volume 4 Issue 9 September 1999 pp 44-52 ... Author Affiliations. Y Narahari1. Department of Computer Science and Automation, Indian Institute of Science, Bangalore 560 012, India.

  8. Net Gain

    International Development Research Centre (IDRC) Digital Library (Canada)

    Describing the effect of tax incentives for import, production, and sale of nets and insecticides; and ..... So far, China is the only country where a system for the routine treatment of ...... 1993), and the trials in Ecuador and Peru (Kroeger et al.

  9. Grain Yield Observations Constrain Cropland CO2 Fluxes Over Europe

    Science.gov (United States)

    Combe, M.; de Wit, A. J. W.; Vilà-Guerau de Arellano, J.; van der Molen, M. K.; Magliulo, V.; Peters, W.

    2017-12-01

    Carbon exchange over croplands plays an important role in the European carbon cycle over daily to seasonal time scales. A better description of this exchange in terrestrial biosphere models—most of which currently treat crops as unmanaged grasslands—is needed to improve atmospheric CO2 simulations. In the framework we present here, we model gross European cropland CO2 fluxes with a crop growth model constrained by grain yield observations. Our approach follows a two-step procedure. In the first step, we calculate day-to-day crop carbon fluxes and pools with the WOrld FOod STudies (WOFOST) model. A scaling factor of crop growth is optimized regionally by minimizing the final grain carbon pool difference to crop yield observations from the Statistical Office of the European Union. In a second step, we re-run our WOFOST model for the full European 25 × 25 km gridded domain using the optimized scaling factors. We combine our optimized crop CO2 fluxes with a simple soil respiration model to obtain the net cropland CO2 exchange. We assess our model's ability to represent cropland CO2 exchange using 40 years of observations at seven European FluxNet sites and compare it with carbon fluxes produced by a typical terrestrial biosphere model. We conclude that our new model framework provides a more realistic and strongly observation-driven estimate of carbon exchange over European croplands. Its products will be made available to the scientific community through the ICOS Carbon Portal and serve as a new cropland component in the CarbonTracker Europe inverse model.

  10. On line portal imaging

    International Nuclear Information System (INIS)

    Munro, Peter

    1995-01-01

    Purpose/Objective: The purpose of this presentation is to review the physics of imaging with high energy x-ray beams; examine the various imaging devices that have been developed for portal imaging; describe some of the image registration methods that have been developed to determine errors in patient positioning quantitatively; and discuss some of the ways that portal imaging has been incorporated into routine clinical practice. Verification of patient positioning has always been an important aspect of external beam radiation therapy. Checks of patient positioning have generally been done with film, however, film suffers from a number of drawbacks, such as poor image display and delays due to film development. Over the past decade many portal imaging devices have been developed by individual investigators and most accelerator manufacturers now offer 'on-line' portal imaging systems, which are intended to overcome the limitations of portal films. The commercial devices can be classified into three categories: T.V. camera-based systems, liquid ionisation chamber systems, and amorphous silicon systems. Many factors influence the quality of images generated by these portal imaging systems. These include factors which are unavoidable (e.g., low subject contrast), factors which depend upon the individual imaging device forming the image (e.g., dose utilisation, spatial resolution) as well as factors which depend upon the characteristics of the linear accelerator irradiating the imaging system (x-ray source size, image magnification). The fundamental factors which limit image quality and the characteristics of individual imaging systems, such as spatial resolution, temporal response, and quantum utilisation will be discussed. One of the major advantages of on-line portal imaging is that many quantitative techniques have been developed to detect errors in patient positioning. The general approach is to register anatomic structures on a portal image with the same

  11. Net Locality

    DEFF Research Database (Denmark)

    de Souza e Silva, Adriana Araujo; Gordon, Eric

    Provides an introduction to the new theory of Net Locality and the profound effect on individuals and societies when everything is located or locatable. Describes net locality as an emerging form of location awareness central to all aspects of digital media, from mobile phones, to Google Maps......, to location-based social networks and games, such as Foursquare and facebook. Warns of the threats these technologies, such as data surveillance, present to our sense of privacy, while also outlining the opportunities for pro-social developments. Provides a theory of the web in the context of the history...... of emerging technologies, from GeoCities to GPS, Wi-Fi, Wiki Me, and Google Android....

  12. Angiography in portal hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Zeitler, E

    1982-04-05

    We report on the cooperative possibilities the radiologist has as to diagnosis and therapy of portal hypertension. The catheter angiography allows to make a differentiation between pre- and intrahepatic bloc and the localization of bleeding esophagus varices. Only after all endoscopic measures with sclerotherapy and Laser coagulation have failed, catheter angiography will be carried out as a therapeutic measure. The future development, however, will give the opportunity to a series of therapeutic attempts on the field of interventional radiology.

  13. Angiography in portal hypertension

    International Nuclear Information System (INIS)

    Zeitler, E.

    1982-01-01

    We report on the cooperative possibilities the radiologist has as to diagnosis and therapy of portal hypertension. The catheter angiography allows to make a differentiation between pre- and intrahepatic bloc and the localization of bleeding esophagus varices. Only after all endoscopic measures with sclerotherapy and Laser coagulation have failed, catheter angiography will be carried out as a therapeutic measure. The future development, however, will give the opportunity to a series of therapeutic attempts on the field of interventional radiology. (orig.) [de

  14. Portal Annular Pancreas

    Science.gov (United States)

    Harnoss, Jonathan M.; Harnoss, Julian C.; Diener, Markus K.; Contin, Pietro; Ulrich, Alexis B.; Büchler, Markus W.; Schmitz-Winnenthal, Friedrich H.

    2014-01-01

    Abstract Portal annular pancreas (PAP) is an asymptomatic congenital pancreas anomaly, in which portal and/or mesenteric veins are encased by pancreas tissue. The aim of the study was to determine the role of PAP in pancreatic surgery as well as its management and potential complication, specifically, postoperative pancreatic fistula (POPF). On the basis of a case report, the MEDLINE and ISI Web of Science databases were systematically reviewed up to September 2012. All articles describing a case of PAP were considered. In summary, 21 studies with 59 cases were included. The overall prevalence of PAP was 2.4% and the patients' mean (SD) age was 55.9 (16.2) years. The POPF rate in patients with PAP (12 pancreaticoduodenectomies and 3 distal pancreatectomies) was 46.7% (in accordance with the definition of the International Study Group of Pancreatic Surgery). Portal annular pancreas is a quite unattended pancreatic variant with high prevalence and therefore still remains a clinical challenge to avoid postoperative complications. To decrease the risk for POPF, attentive preoperative diagnostics should also focus on PAP. In pancreaticoduodenectomy, a shift of the resection plane to the pancreas tail should be considered; in extensive pancreatectomy, coverage of the pancreatic remnant by the falciform ligament could be a treatment option. PMID:25207658

  15. Obliterative portal venopathy without portal hypertension: an underestimated condition.

    Science.gov (United States)

    Guido, Maria; Sarcognato, Samantha; Sonzogni, Aurelio; Lucà, Maria Grazia; Senzolo, Marco; Fagiuoli, Stefano; Ferrarese, Alberto; Pizzi, Marco; Giacomelli, Luciano; Colloredo, Guido

    2016-03-01

    Obliterative portal venopathy without portal hypertension has been described by a single study in a limited number of patients, thus very little is known about this clinical condition. This study aimed to investigate the prevalence of obliterative portal venopathy and its clinical-pathological correlations in patients with cryptogenic chronic liver test abnormalities without clinical signs of portal hypertension. We analysed 482 liver biopsies from adults with non-cirrhotic cryptogenic chronic liver disorders and without any clinical signs of portal hypertension, consecutively enrolled in a 5-year period. Twenty cases of idiopathic non-cirrhotic portal hypertension diagnosed in the same period, were included for comparison. Histological findings were matched with clinical and laboratory features. Obliterative portal venopathy was identified in 94 (19.5%) of 482 subjects and in all 20 cases of idiopathic non-cirrhotic portal hypertension: both groups shared the entire spectrum of histological changes described in the latter condition. The prevalence of incomplete fibrous septa and nodular regenerative hyperplasia was higher in the biopsies of idiopathic non-cirrhotic portal hypertension (P = 0.006 and P = 0.002), a possible hint of a more advanced stage of the disease. The two groups also shared several clinical laboratory features, including a similar liver function test profile, concomitant prothrombotic conditions and extrahepatic autoimmune disorders. Obliterative portal venopathy occurs in a substantial proportion of patients with unexplained chronic abnormal liver function tests without portal hypertension. The clinical-pathological profile of these subjects suggests that they may be in an early (non-symptomatic) stage of idiopathic non-cirrhotic portal hypertension. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Portal hemodynamics in chronic portal-systemic encephalopathy

    International Nuclear Information System (INIS)

    Takashi, Motohide; Igarashi, Masahiko; Hino, Shinichi; Takayasu, Kenichi; Goto, Nobuaki; Musha, Hirotaka; Ohnishi, Kunihiko; Okuda, Kunio

    1985-01-01

    A portal hemodynamic study was made in 7 consecutive patients with chronic portal-systemic encephalopathy by percutaneous transhepatic catheterization of the portal vein and injecting contrast medium into the superior mesenteric vein or by superior mesenteric arterial portography in comparison with patients without encephalopathy studied by percutaneous catheterization of these veins. It is suggested that chronic portal-systemic encephalopathy is a result of a large collateral route shunting a large proportion of the superior mesenteric venous blood into systemic circulation, and that development of such collaterals precludes formation of large esophageal varices. (Auth.)

  17. Knowledge Portals: Ontologies at Work

    OpenAIRE

    Staab, Steffen; Maedche, Alexander

    2001-01-01

    Knowledge portals provide views onto domain-specific information on the World Wide Web, thus helping their users find relevant, domain-specific information. The construction of intelligent access and the contribution of information to knowledge portals, however, remained an ad hoc task, requiring extensive manual editing and maintenance by the knowledge portal providers. To diminish these efforts, we use ontologies as a conceptual backbone for providing, accessing, and structuring information...

  18. Duplex sonography in portal hypertension

    International Nuclear Information System (INIS)

    Kwon, Hyuk Po; Jang, J. C.; Park, B. H.

    1990-01-01

    We measure the diameter and blood velocity of the portal vein in 50 patients with cirrhosis of the liver and 40 healthy subjects, and calculated cross sectional area, mean blood flow velocity, blood flow volume and congestion index. In patients with cirrhosis of the liver, the cross sectional area of the portal vein was significantly increased: the mean blood flow volume was significantly reduced; the blood flow volume was significantly increased; the congestion index of the portal vein was significantly increased. Duples sonography may play an important role in the diagnosis of portal hypertension

  19. On ANENT WEB portal: A quick view from Hanoi

    International Nuclear Information System (INIS)

    Phung Van Duan

    2005-01-01

    To set up a WEB-portal is one of the contents of an important activity of the Asian Network for Education in Nuclear Technology (ANENT). The web portal is directly connected with the other activities of ANENT. The first version of the web portal was prepared in time. It reflects the activities of ANENT as well as the important events and activities of IAEA. The NET DB can already serve as an official source for starting and developing many ANENT activities. Nevertheless, the compilation would be more valuable if it is enriched with additional information on material for Nuclear Technology Education, on activities of the ANENT member-institutions in field of Nuclear Education and so on. It would be desirable to intensify linkage for the purpose of effective exploration of the available information of the ANENT member-institutions as well as exploration of the other related web sites such as the one of ENEN and so on. To upgrade the web-portal and to diversify it might be one of the essential tasks for development of the web-portal. Developing the web-portal might simultaneously mean equipping it with the reference curricula and appropriate contents of the necessary courses for all forms of learning in nuclear fields which are commonly acceptable in ANENT. So, for development of the web-portal for ANENT, it would be also necessary to accelerate implementation of the other ANENT Activities, especially Activity 4 establishment of reference curricula and facilitating credit transfer and mutual recognition of degrees

  20. The Protein Model Portal.

    Science.gov (United States)

    Arnold, Konstantin; Kiefer, Florian; Kopp, Jürgen; Battey, James N D; Podvinec, Michael; Westbrook, John D; Berman, Helen M; Bordoli, Lorenza; Schwede, Torsten

    2009-03-01

    Structural Genomics has been successful in determining the structures of many unique proteins in a high throughput manner. Still, the number of known protein sequences is much larger than the number of experimentally solved protein structures. Homology (or comparative) modeling methods make use of experimental protein structures to build models for evolutionary related proteins. Thereby, experimental structure determination efforts and homology modeling complement each other in the exploration of the protein structure space. One of the challenges in using model information effectively has been to access all models available for a specific protein in heterogeneous formats at different sites using various incompatible accession code systems. Often, structure models for hundreds of proteins can be derived from a given experimentally determined structure, using a variety of established methods. This has been done by all of the PSI centers, and by various independent modeling groups. The goal of the Protein Model Portal (PMP) is to provide a single portal which gives access to the various models that can be leveraged from PSI targets and other experimental protein structures. A single interface allows all existing pre-computed models across these various sites to be queried simultaneously, and provides links to interactive services for template selection, target-template alignment, model building, and quality assessment. The current release of the portal consists of 7.6 million model structures provided by different partner resources (CSMP, JCSG, MCSG, NESG, NYSGXRC, JCMM, ModBase, SWISS-MODEL Repository). The PMP is available at http://www.proteinmodelportal.org and from the PSI Structural Genomics Knowledgebase.

  1. CT portal venography manifestations of portal collateral circulation in patients with portal hypertension due to cirrhosis

    International Nuclear Information System (INIS)

    Ni Ming; Lv Weifu; Deng Kexue

    2009-01-01

    Objective: To analyze CT portal venography (CTPV) manifestations of portal collateral circulation in patients with cirrhosis by using a 16-detector row spiral CT scanner. Methods: CTPV was performed in 36 patients with portal hypertension due to cirrhosis, the diagnosis was proved by clinical data, hepatic function findings and imaging signs. By using post-processing reconstruction technique, 3D images of portal venous system and portal collateral circulation were obtained. Results: CTPV images displayed the portal venous system and its collateral circulation stereoscopically. Of 36 patients, left gastric varices were seen in 29(80.6%), lower esophageal varices in 18(50.0%), short gastric or posterior gastric varices in 15(41.7%), paraesophageal varices in 9(25.0%), gastro-renal or splenorenal shunts in 8(22.2%), spongelike transformation of portal vein in 7(19.4%), paraumbilical and abdominal wall varices in 6(16.7%), congenital cavernous in 6(16.7%) and paravertebral venous shunts in 4(11.1%). Conclusion: CTPV can well display the site, extent and severity of the portal collateral circulation in patients with portal hypertension due to cirrhosis,which is of great clinical importance for judging the patient's condition, for selecting therapeutic protocols and for estimating prognosis. (authors)

  2. Information Portals: A New Tool for Teaching Information Literacy Skills

    OpenAIRE

    Kolah, Debra; Fosmire, Michael

    2010-01-01

    Librarians at Rice and Purdue Universities created novel assignments to teach students important information literacy skills. The assignments required the students to use a third-party web site, PageFlakes and NetVibes, respectively, to create a dynamically updated portal to information they needed for their research and class projects. The use of off-the-shelf web 2.0 technology to enable students to discover the latest information in their subject areas of interest provides an engaging, han...

  3. Lunar and Vesta Web Portals

    Science.gov (United States)

    Law, E.; JPL Luna Mapping; Modeling Project Team

    2015-06-01

    The Lunar Mapping and Modeling Project offers Lunar Mapping and Modeling Portal (http://lmmp.nasa.gov) and Vesta Trek Portal (http://vestatrek.jpl.nasa.gov) providing interactive visualization and analysis tools to enable users to access mapped Lunar and Vesta data products.

  4. Portal dosimetry in wedged beams

    NARCIS (Netherlands)

    Spreeuw, Hanno; Rozendaal, Roel; Camargo, Priscilla; Mans, Anton; Wendling, Markus; Olaciregui-Ruiz, Igor; Sonke, Jan-Jakob; van Herk, Marcel; Mijnheer, Ben

    2015-01-01

    Portal dosimetry using electronic portal imaging devices (EPIDs) is often applied to verify high-energy photon beam treatments. Due to the change in photon energy spectrum, the resulting dose values are, however, not very accurate in the case of wedged beams if the pixel-to-dose conversion for the

  5. WLCG Operations portal demo tutorial

    CERN Multimedia

    CERN. Geneva

    2016-01-01

    This is a navigation through http://wlcg-ops.web.cern.ch/ the Worldwide LHC Computing Grid (WLCG) Operations' portal. In this portal you will find documentation and information about WLCG Operation activities for: System Administrators at the WLCG sites LHC Experiments Operation coordination people, including Task Forces and Working Groups

  6. Health literacy and patient portals.

    Science.gov (United States)

    Gu, Yulong; Orr, Martin; Warren, Jim

    2015-06-01

    Health literacy has been described as the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions. Improving health literacy may serve to promote concordance with therapy, engage patients in their own health care, and improve health outcomes. Patient portal technology aims at enabling patients and families to have easy access to key information in their own medical records and to communicate with their health care providers electronically. However, there is a gap in our understanding of how portals will improve patient outcome. The authors believe patient portal technology presents an opportunity to improve patient concordance with prescribed therapy, if adequate support is provided to equip patients (and family/carers) with the knowledge needed to utilise the health information available via the portals. Research is needed to understand what a health consumer will use patient portals for and how to support a user to realise the technology's potential.

  7. Portal monitoring technology control process

    International Nuclear Information System (INIS)

    York, R.L.

    1998-01-01

    Portal monitors are an important part of the material protection, control, and accounting (MPC and A) programs in Russia and the US. Although portal monitors are only a part of an integrated MPC and A system, they are an effective means of controlling the unauthorized movement of special nuclear material (SNM). Russian technical experts have gained experience in the use of SNM portal monitors from US experts ad this has allowed them to use the monitors more effectively. Several Russian institutes and companies are designing and manufacturing SNM portal monitors in Russia. Interactions between Russian and US experts have resulted in improvements to the instruments. SNM portal monitor technology has been effectively transferred from the US to Russia and should be a permanent part of the Russian MPC and A Program. Progress in the implementation of the monitors and improvements to how they are used are discussed

  8. The Portuguese Climate Portal

    Science.gov (United States)

    Gomes, Sandra; Deus, Ricardo; Nogueira, Miguel; Viterbo, Pedro; Miranda, Miguel; Antunes, Sílvia; Silva, Alvaro; Miranda, Pedro

    2016-04-01

    The Portuguese Local Warming Website (http://portaldoclima.pt) has been developed in order to support the society in Portugal in preparing for the adaptation to the ongoing and future effects of climate change. The climate portal provides systematic and easy access to authoritative scientific data ready to be used by a vast and diverse user community from different public and private sectors, key players and decision makers, but also to high school students, contributing to the increase in knowledge and awareness on climate change topics. A comprehensive set of regional climate variables and indicators are computed, explained and graphically presented. Variables and indicators were built in agreement with identified needs after consultation of the relevant social partners from different sectors, including agriculture, water resources, health, environment and energy and also in direct cooperation with the Portuguese National Strategy for Climate Change Adaptation (ENAAC) group. The visual interface allows the user to dynamically interact, explore, quickly analyze and compare, but also to download and import the data and graphics. The climate variables and indicators are computed from state-of-the-art regional climate model (RCM) simulations (e.g., CORDEX project), at high space-temporal detail, allowing to push the limits of the projections down to local administrative regions (NUTS3) and monthly or seasonal periods, promoting local adaptation strategies. The portal provides both historical data (observed and modelled for the 1971-2000 period) and future climate projections for different scenarios (modelled for the 2011-2100 period). A large effort was undertaken in order to quantify the impacts of the risk of extreme events, such as heavy rain and flooding, droughts, heat and cold waves, and fires. Furthermore the different climate scenarios and the ensemble of RCM models, with high temporal (daily) and spatial (~11km) detail, is taken advantage in order to

  9. Software tool for portal dosimetry research.

    Science.gov (United States)

    Vial, P; Hunt, P; Greer, P B; Oliver, L; Baldock, C

    2008-09-01

    This paper describes a software tool developed for research into the use of an electronic portal imaging device (EPID) to verify dose for intensity modulated radiation therapy (IMRT) beams. A portal dose image prediction (PDIP) model that predicts the EPID response to IMRT beams has been implemented into a commercially available treatment planning system (TPS). The software tool described in this work was developed to modify the TPS PDIP model by incorporating correction factors into the predicted EPID image to account for the difference in EPID response to open beam radiation and multileaf collimator (MLC) transmitted radiation. The processes performed by the software tool include; i) read the MLC file and the PDIP from the TPS, ii) calculate the fraction of beam-on time that each point in the IMRT beam is shielded by MLC leaves, iii) interpolate correction factors from look-up tables, iv) create a corrected PDIP image from the product of the original PDIP and the correction factors and write the corrected image to file, v) display, analyse, and export various image datasets. The software tool was developed using the Microsoft Visual Studio.NET framework with the C# compiler. The operation of the software tool was validated. This software provided useful tools for EPID dosimetry research, and it is being utilised and further developed in ongoing EPID dosimetry and IMRT dosimetry projects.

  10. New ICPP portal monitor

    International Nuclear Information System (INIS)

    Georgeson, M.A.; Nichols, C.E.

    1981-04-01

    A large area gas filled proportional-detector portal monitor mounted in a swinging door frame has been designed and developed at the Idaho Chemical Processing Plant (ICPP). This monitor extends the sensitivity and speed of personnel contamination detection to levels equal to or exceeding that obtained using hand-held portable survey techniques. The new monitor has state-of-the-art electronics which result in rapid response, and use statistical principles in the alarm logic to reduce or eliminate spurious alarms. In addition, the evaluation of this instrument indicates that it will detect small enough quantities of U-235 in shielded containers to meet current special nuclear materials (SNM) detection standards. Simultaneous detection of very low level contamination and small quantities of SNM results in a monitor particularly useful for nuclear installations

  11. Congestive index of portal vein

    International Nuclear Information System (INIS)

    Kim, Won Ho; Kim, H. K.; Lee, S. C.; Han, S. H.; Han, K. H.; Chung, J. B.; Choi, H. J.

    1989-01-01

    In patients with portal hypertension, the blood flow volume is maintained despite decreased blood flow velocity due to enlargement of the vascular cross sectional area. Thus, the 'congestion index' of the portal vein, which is the ratio between the cross sectional area (cm2) and the blood flow velocity (cm/sec) determined by a Doppler ultrasonography, may be a sensitive index by which to assess portal hypertension. We performed Doppler ultrasonography on 24 normal subjects, 14 patients with biopsy proved chronic active hepatitis and 55 patients with liver cirrhosis in order to assess the diagnostic value of the congestion index. The cross sectional area of the portal vein was significantly enlarged and the mean blood flow velocity was significantly reduced in patients with liver cirrhosis compared with controls. However, the blood flow volume was no difference. The congestion index of the portal vein was significantly increased in patients with liver cirrhosis (0.113+0.035) compared with patients with chronic active hepatitis(0.078+0.029) (p<0.001) and controls (0.053+0.016) (p<0.001). The sensitivity, specificity and predictability of the congestion index for detection of patients with the cirrhosis of the liver were 76.4%, 100% and 100% respectively, when the normal range was set at mean+2SD. The results suggest that the congestion index of the portal vein may pla a significant role in diagnosis of portal hypertensive patients

  12. Information Portal Costs and Benefits

    Directory of Open Access Journals (Sweden)

    Lorena BATAGAN

    2006-01-01

    Full Text Available All transformations of our society are the product of the large use of Information and Communications Technologies (ICT and Internet. ICT are technologies which facilitate communication, processing, and transmission of information by electronic means. It is very important to use the new technologies to the correct value because this determinate an increase of global benefits. Portal provides a consistent way to select, evaluate, prioritize and plan the right information. In research we point the important costs and benefits for an informational portal. The portal for local administrative determinate for citizens the access to information of interest and on the other hand make easier for employer to manage the documents.

  13. The Higgs Portal and Cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Assamagan, Ketevi [Brookhaven National Lab. (BNL), Upton, NY (United States); Chen, Chien-Yi [Perimeter Inst. for Theoretical Physics, Waterloo, ON (Canada); Univ. of Victoria, BC (Canada); Chou, John Paul [Rutgers Univ., Piscataway, NJ (United States); Curtin, David [Univ. of Maryland, College Park, MD (United States); Fedderke, Michael A. [Univ. of Chicago, IL (United States); Gershtein, Yuri [Rutgers Univ., Piscataway, NJ (United States); He, Xiao-Gang [Shanghai Jiao Tong Univ. (China); Klute, Markus [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Kozaczuk, Jonathon [TRIUMF, Vancouver, BC (Canada); Kotwal, Ashutosh [Duke Univ., Durham, NC (United States); Lowette, Steven [Vrije Univ., Brussels (Belgium); No, Jose Miguel [Univ. of Sussex, Brighton (United Kingdom); Plehn, Tilman [Heidelberg Univ. (Germany); Qian, Jianming [Univ. of Michigan, Ann Arbor, MI (United States); Ramsey-Musolf, Michael [Univ. of Massachusetts, Amherst, MA (United States); Safonov, Alexei [Texas A & M Univ., College Station, TX (United States); Shelton, Jessie [Univ. of Illinois, Urbana-Champaign, IL (United States); Spannowsky, Michael [Durham Univ. (United Kingdom); Su, Shufang [Univ. of Arizona, Tucson, AZ (United States); Walker, Devin G. E. [Univ. of Washington, Seattle, WA (United States); Willocq, Stephane [Univ. of Massachusetts, Amherst, MA (United States); Winslow, Peter [Univ. of Massachusetts, Amherst, MA (United States)

    2016-04-18

    Higgs portal interactions provide a simple mechanism for addressing two open problems in cosmology: dark matter and the baryon asymmetry. In the latter instance, Higgs portal interactions may contain the ingredients for a strong first-order electroweak phase transition as well as new CP-violating interactions as needed for electroweak baryogenesis. These interactions may also allow for a viable dark matter candidate. We survey the opportunities for probing the Higgs portal as it relates to these questions in cosmology at the LHC and possible future colliders.

  14. Implementation of CLP4NET in Bulgaria

    International Nuclear Information System (INIS)

    Naydenova, I.; Pironkov, L.; Filipov, A.; Petrova, T.; Tsochev, G.; Ganev, I.

    2016-01-01

    Full text: Networking solutions (networks of excellence, communities of practice, knowledge portals, etc.) are recognized as effective tools for nuclear training and education services, transfer of good practices, knowledge and programmes, and knowledge management. In addition, the e-learning is recommended as a state of the art and cost effective approach for supplementing the traditional face to face training and education programmes. Thus, the Cyber Learning Platform for Nuclear Education and Training (CLP4NET) was implemented into the Kozloduy Nuclear Power Plant (KNPP) Training System. Based on the experience of KNPP, the CLP4NET was implemented also at the College of Energy and Electronics (CEE), Technical University of Sofia (TU-Sofia), providing an appropriate tool for further establishment of a National Nuclear Network of Competency. The current study is focused mainly on specific issues and lessons learned during the installation of CLP4NET at the CEE, TU-Sofia. (author

  15. Ozone (Environmental Health Student Portal)

    Science.gov (United States)

    Skip Navigation National Library of Medicine Environmental Health Student Portal Connecting Middle School Students to Environmental Health Information Menu Home Air Pollution Air Pollution Home Indoor Air Pollution Outdoor ...

  16. Pesticides (Environmental Health Student Portal)

    Science.gov (United States)

    Skip Navigation National Library of Medicine Environmental Health Student Portal Connecting Middle School Students to Environmental Health Information Menu Home Air Pollution Air Pollution Home Indoor Air Pollution Outdoor ...

  17. Radioisotopic evaluation of portal circulation

    International Nuclear Information System (INIS)

    Maliska, C.; Rosenthal, D.

    1986-01-01

    The use of a radio-tracer of portal circulation through the intestine, should prevent cruel punctures in the portal-vein or spleen as it is usually the case with traditional methods in the study of portal-system. The absorption of I-131 and Tc-99m, previously cheked in rabbits presented similar results in dogs. The time of circulation between terminal large-intestine and the liver (t-RF) was determined by external counting at hepatic level by recording radioactivity variation-time. In healthy animals the t-RF was from 20to 60 seconds, with average time of 42 seconds. In 2 animals with partial binding of portal-vein the t-RF went up to 110 and 120 seconds. (Author) [pt

  18. Fluxes of nitrogen in Chaliyar River Estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Xavier, J.K.; Joseph, T.; Paimpillii, J.S.

    pool is from the organic -N. The net fluxes of inorganic nutrients in monsoon and post monsoon season are very large- with very small positive or negative fluxes for the pre-monsoon months. The average net fluxes are 4.97 to 9.61 mg m-2 s-1...

  19. Portal pressure correlated to visceral circulation times

    Energy Technology Data Exchange (ETDEWEB)

    Friman, L [Serafimerlasarettet, Stockholm (Sweden)

    1979-01-01

    Visceral angiography was performed in 7 patients with normal portal pressure and in 10 with portal hypertension. Circulation times, size of vessels and portal pressure were determined. At celiac angiography, a direct correlation was found between time for maximum filling of portal vein and portal pressure, provided no vascular abnormalities existed. At superior mesenteric angiography such a correlation was not found; loss of flow by shunts in portal hypertension being one explanation. Portocaval shunts are common in the celiac system, but uncommon in the superior mesenteric system.

  20. Portal pressure correlated to visceral circulation times

    International Nuclear Information System (INIS)

    Friman, L.

    1979-01-01

    Visceral angiography was performed in 7 patients with normal portal pressure and in 10 with portal hypertension. Circulation times, size of vessels and portal pressure were determined. At celiac angiography, a direct correlation was found between time for maximum filling of portal vein and portal pressure, provided no vascular abnormalities existed. At superior mesenteric angiography such a correlation was not found; loss of flow by shunts in portal hypertension being one explanation. Portocaval shunts are common in the celiac system, but uncommon in the superior mesenteric system. (Auth.)

  1. Portal monitor incorporating smart probes

    International Nuclear Information System (INIS)

    Bartos, D.; Constantin, F.; Guta, T.

    2003-01-01

    Portal monitors are intended for detection of radioactive and special nuclear materials in vehicles, pedestrians, luggage, as well as for prevention of illegal traffic of radioactive sources. Monitors provide audio and visual alarms when radioactive and/or special nuclear materials are detected. They can be recommended to officers of customs, border guard and emergency services, civil defense, fire brigades, police and military departments or nuclear research or energetic facilities. The portal monitor developed by us consists in a portal frame, which sustains five intelligent probes having long plastic scintillator (0.5 liters each). The probes communicate, by serial transmission, with a Central Unit constructed on the basis of the 80552 microcontroller. This one manages the handshake, calculates the background, establishes the measuring time, starts and stops each measurement and makes all the other decisions. Sound signals and an infrared sensor monitor the passing through the portal and the measuring procedure. For each measurement the result is displayed on a LCD device contaminated/uncontaminated; for the contaminated case a loud and long sound signal is also issued. An RS 232 serial interface is provided in order to further developments or custom made devices. As a result, the portal monitor detects 1 μ Ci 137 Cs, spread all over a human body, in a 20 μR/h gamma background for a measuring time of 1.5 or 10 seconds giving a 99% confidence factor. (authors)

  2. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt

    1987-01-01

    The author describes a Petri net model, called coloured Petri nets (CP-nets), by means of which it is possible to describe large systems without having to cope with unnecessary details. The author introduces CP-nets and provide a first impression of their modeling power and the suitability...

  3. Learning Visual Basic NET

    CERN Document Server

    Liberty, Jesse

    2009-01-01

    Learning Visual Basic .NET is a complete introduction to VB.NET and object-oriented programming. By using hundreds of examples, this book demonstrates how to develop various kinds of applications--including those that work with databases--and web services. Learning Visual Basic .NET will help you build a solid foundation in .NET.

  4. CT findings of portal vein aneurysm

    International Nuclear Information System (INIS)

    Yang, Dal Mo; Chang, Mi Son; Yoon, Myung Hwan; Kim, Hak Soo; Kim, Hyung Sik; Chung, Hyo Sun; Chung, Jin Woo

    1999-01-01

    To describe the CT findings of portal vein aneurysm in eight patients. All patients included in this study (two men and six women) underwent CT examinations between October 1996 and June1998. Of these eight, three were suffering from hepatic disease and portal hypertension. We determined the location, shape, size, and characteristics of the lesions, and the presence or absence of portal vein anomaly. Seven patients had intrahepatic portal vein aneurysm (at the umbilical portion of the left portal vein in five patients, between the transverse and umbilical portion of the left portal vein in one, and at the bifurcation of the anterior and posterior branch of the right portal vein in one), while extrahepatic portal vein aneurysm, at the confluence of the superior mesenteric and splenic vein was found in only one. Lesions were cyst-shaped in seven cases and saccular in one, and showed well-circumscribed, markedly enhanced mass, which communicated with the portal vein and/or gives off major branches. Portal vein anomaly, in which the right anterior segmental portal vein originated from the umbilical portion of the left portal vein, was seen in three patients. In all three, intrahepatic portal vein aneurysm was present at the umbilical portion of the left portal vein, and in one, the umbilical protion of the left portal vein was located to the right of the Cantlic line. CT examination can help reveal portal vein aneurysm by detecting a well-circumscribed, markedly enhanced mass which communicates with the portal vein and/or gives off major branches

  5. The Higgs portal above threshold

    Energy Technology Data Exchange (ETDEWEB)

    Craig, Nathaniel [Department of Physics, University of California,Santa Barbara, CA 93106 (United States); Lou, Hou Keong [Department of Physics, Princeton University,Princeton, NJ 08540 (United States); McCullough, Matthew [Theory Division, CERN,1211 Geneva 23 (Switzerland); Thalapillil, Arun [Department of Physics and Astronomy, Rutgers University,Piscataway, NJ 08854 (United States)

    2016-02-18

    The discovery of the Higgs boson opens the door to new physics interacting via the Higgs Portal, including motivated scenarios relating to baryogenesis, dark matter, and electroweak naturalness. We systematically explore the collider signatures of singlet scalars produced via the Higgs Portal at the 14 TeV LHC and a prospective 100 TeV hadron collider. We focus on the challenging regime where the scalars are too heavy to be produced in the decays of an on-shell Higgs boson, and instead are produced primarily via an off-shell Higgs. Assuming these scalars escape the detector, promising channels include missing energy in association with vector boson fusion, monojets, and top pairs. We forecast the sensitivity of searches in these channels at √s=14 & 100 TeV and compare collider reach to the motivated parameter space of singlet-assisted electroweak baryogenesis, Higgs Portal dark matter, and neutral naturalness.

  6. The Higgs portal above threshold

    International Nuclear Information System (INIS)

    Craig, Nathaniel; Lou, Hou Keong; McCullough, Matthew; Thalapillil, Arun

    2016-01-01

    The discovery of the Higgs boson opens the door to new physics interacting via the Higgs Portal, including motivated scenarios relating to baryogenesis, dark matter, and electroweak naturalness. We systematically explore the collider signatures of singlet scalars produced via the Higgs Portal at the 14 TeV LHC and a prospective 100 TeV hadron collider. We focus on the challenging regime where the scalars are too heavy to be produced in the decays of an on-shell Higgs boson, and instead are produced primarily via an off-shell Higgs. Assuming these scalars escape the detector, promising channels include missing energy in association with vector boson fusion, monojets, and top pairs. We forecast the sensitivity of searches in these channels at √s=14 & 100 TeV and compare collider reach to the motivated parameter space of singlet-assisted electroweak baryogenesis, Higgs Portal dark matter, and neutral naturalness.

  7. Building an Archival Collections Portal

    Directory of Open Access Journals (Sweden)

    Stuart Marquis

    2008-06-01

    Full Text Available Columbia University Libraries has developed the Archival Collections Portal, a unified search system helping users discover archival resources in a streamlined way. We combined the power of Lucene and Solr to search XML, parse JSON objects, create EAD-compliant documents, and deliver results in an easy-to-use interface. By reusing MARC records and employing new search engine features and techniques, we are able to bring important and hard-to-find collections to researchers and archivists. The canonical home page of the Portal is http://www.columbia.edu/library/archival/.

  8. 29 CFR 785.24 - Principles noted in Portal-to-Portal Bulletin.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Principles noted in Portal-to-Portal Bulletin. 785.24 Section 785.24 Labor Regulations Relating to Labor (Continued) WAGE AND HOUR DIVISION, DEPARTMENT OF LABOR... of Principles Preparatory and Concluding Activities § 785.24 Principles noted in Portal-to-Portal...

  9. From EGEE Operations Portal towards EGI Operations Portal

    Science.gov (United States)

    Cordier, Hélène; L'Orphelin, Cyril; Reynaud, Sylvain; Lequeux, Olivier; Loikkanen, Sinikka; Veyre, Pierre

    Grid operators in EGEE have been using a dedicated dashboard as their central operational tool, stable and scalable for the last 5 years despite continuous upgrade from specifications by users, monitoring tools or data providers. In EGEE-III, recent regionalisation of operations led the Operations Portal developers to conceive a standalone instance of this tool. We will see how the dashboard reorganization paved the way for the re-engineering of the portal itself. The outcome is an easily deployable package customized with relevant information sources and specific decentralized operational requirements. This package is composed of a generic and scalable data access mechanism, Lavoisier; a renowned php framework for configuration flexibility, Symfony and a MySQL database. VO life cycle and operational information, EGEE broadcast and Downtime notifications are next for the major reorganization until all other key features of the Operations Portal are migrated to the framework. Features specifications will be sketched at the same time to adapt to EGI requirements and to upgrade. Future work on feature regionalisation, on new advanced features or strategy planning will be tracked in EGI- Inspire through the Operations Tools Advisory Group, OTAG, where all users, customers and third parties of the Operations Portal are represented from January 2010.

  10. Quantitative vs. subjective portal verification using digital portal images.

    Science.gov (United States)

    Bissett, R; Leszczynski, K; Loose, S; Boyko, S; Dunscombe, P

    1996-01-15

    Off-line, computer-aided prescription (simulator) and treatment (portal) image registration using chamfer matching has been implemented on PC based viewing station. The purposes of this study were (a) to evaluate the performance of interactive anatomy and field edge extraction and subsequent registration, and (b) to compare observer's perceptions of field accuracy with measured discrepancies following anatomical registration. Prescription-treatment image pairs for 48 different patients were examined in this study. Digital prescription images were produced with the aid of a television camera and a digital frame grabber, while the treatment images were obtained directly from an on-line portal imaging system. To facilitate perception of low contrast anatomical detail, on-line portal images were enhanced with selective adaptive histogram equalization prior to extraction of anatomical edges. Following interactive extraction of anatomical and field border information by an experienced observer, the identified anatomy was registered using chamfer matching. The degree of conformity between the prescription and treatment fields was quantified using several parameters, which included relative prescription field coverage and overcoverage, as well as the translational and rotational displacements as measured by chamfer matching applied to the boundaries of the two fields. These quantitative measures were compared with subjective evaluations made by four radiation oncologists. All the images in this series that included a range of the most commonly seen treatment sites were registered and the conformity parameters were found. The mean treatment/prescription field coverage and overcoverage were approximately 95 and 7%, respectively before registration. The mean translational displacement in the transverse and cranio-caudal directions were 2.9 and 3.4 mm, respectively. The mean rotational displacement was approximately 2 degrees. For all four oncologists, the portals classified

  11. Magnetic Resonance Imaging of a Liver Hydatid Cyst Invading the Portal Vein and Causing Portal Cavernomatosis.

    Science.gov (United States)

    Herek, Duygu; Sungurtekin, Ugur

    2015-01-01

    Hepatic hydatid cysts rarely invade portal veins causing portal cavernomatosis as a secondary complication. We report the case of a patient with direct invasion of the right portal vein by hydatid cysts causing portal cavernomatosis diagnosed via magnetic resonance imaging (MRI). The presented case highlights the useful application of MRI with T2-weighted images and gadolinium-enhanced T1-weighted images in the diagnosis of hepatic hydatid lesions presenting with a rare complication of portal cavernomatosis.

  12. Radiologic investigation of portal hypertension

    International Nuclear Information System (INIS)

    Becker, C.; Wegmueller, H.

    1993-01-01

    Radiologic evaluation of patients with portal hypertension in the pre- and postoperative period can be done with several non-invasive or invasive imaging modalities which offer complementary information. Doppler-ultrasonography (-US) is the method of choice for initial non-invasive screening as well as for follow-up tests after shunt surgery. The diagnostic information provided by Doppler-US regarding morphology and blood flow in the upper abdominal organs and vessels is sufficient in many instances. Dynamic computed tomography (CT), magnetic resonance tomography (MRT) and recently, magnetic resonance angiography (MRA) are additional non-invasive imaging techniques that may add valuable information if necessary. Conventional angiography is usually performed immediately prior to surgery to demonstrate the vascular morphology. The standard angiographic technique to demonstrate both the arterial and portal venous system is arterioportography (late-phase portography) by means of selective catheterization of the celiac, the splenic, the superior mesenteric or inferior mesenteric arteries. The dose of iodinated contrast material may be reduced by 50% if digital subtraction angiography is used instead of the conventional technique. Inferior venacavography and hepatic venography are indicated in patients with suspected postsinusoidal portal hypertension, e.g. the Budd-Chiari syndrome; hepatic wedge manometry offers valuable information regarding pressure gradients between the portal and systemic venous system prior to shunt surgery. The angiographic access through the inferior vena cava is also used for direct catheterization of surgical porto-caval or spleno-renal shunts for both angiography, manometry and, if necessary, balloon angioplasty. (authors)

  13. Sonographic detection of portal venous gas

    International Nuclear Information System (INIS)

    Lee, Wang Yul; Lee, S. K.; Cho, O. K.

    1989-01-01

    Portal venous gas suggests underlying bowel disease such as strangulating intestinal obstruction and its demonstration carries with it an important implications with respect to patient management. Radiography has been the gold standard for the detection of portal venous gas. We have experienced two cases of portal venous gas diagnosed by ultrasound. Sonographic findings were floating echoes in the main portal vein and highly echogenic linear or patchy echoes within the hepatic parenchyma. Simple abdominal films of those cases failed to demonstrate gas in the portal venous system

  14. Planning of nets

    International Nuclear Information System (INIS)

    Carberry, M

    1996-01-01

    The paper is about the planning of nets in areas of low density like it is the case of the rural areas. The author includes economic and technological aspects, planning of nets, demands and management among others

  15. Annotating Coloured Petri Nets

    DEFF Research Database (Denmark)

    Lindstrøm, Bo; Wells, Lisa Marie

    2002-01-01

    Coloured Petri nets (CP-nets) can be used for several fundamentally different purposes like functional analysis, performance analysis, and visualisation. To be able to use the corresponding tool extensions and libraries it is sometimes necessary to include extra auxiliary information in the CP......-net. An example of such auxiliary information is a counter which is associated with a token to be able to do performance analysis. Modifying colour sets and arc inscriptions in a CP-net to support a specific use may lead to creation of several slightly different CP-nets – only to support the different uses...... of the same basic CP-net. One solution to this problem is that the auxiliary information is not integrated into colour sets and arc inscriptions of a CP-net, but is kept separately. This makes it easy to disable this auxiliary information if a CP-net is to be used for another purpose. This paper proposes...

  16. DESARROLLO DE UN PORTAL WEB CON TECNOLOGIA PHP/MYSQL

    OpenAIRE

    IBAÑEZ RAAD, FABRICIO CARLOS

    2015-01-01

    Este trabajo de final de grado consta en la implementación de la tecnología PHP y MySQL en un portal web desarrollado con con NetBeans IDE. La ventaja es que tanto PHP, MySQL y NetBeans son open source con lo cual se evita el sobrecoste de pagar licencias adicionales a la hora de crear una web. En este proyecto he implementado un CMS (sistema de gestión de contenidos) donde el usuario puede poner en su web los objetos que el desee a través de este CMS de una forma dinámica y rápida sin tener...

  17. Intelligent interaction based on holographic personalized portal

    Directory of Open Access Journals (Sweden)

    Yadong Huang

    2017-06-01

    Full Text Available Purpose – The purpose of this paper is to study the architecture of holographic personalized portal, user modeling, commodity modeling and intelligent interaction. Design/methodology/approach – In this paper, the authors propose crowd-science industrial ecological system based on holographic personalized portal and its interaction. The holographic personality portal is based on holographic enterprises, commodities and consumers, and the personalized portal consists of accurate ontology, reliable supply, intelligent demand and smart cyberspace. Findings – The personalized portal can realize the information acquisition, characteristic analysis and holographic presentation. Then, the intelligent interaction, e.g. demand decomposition, personalized search, personalized presentation and demand prediction, will be implemented within the personalized portal. Originality/value – The authors believe that their work on intelligent interaction based on holographic personalized portal, which has been first proposed in this paper, is innovation focusing on the interaction between intelligence and convenience.

  18. NUCLEONICA: a nuclear science portal

    International Nuclear Information System (INIS)

    Magill, J.; Galy, J.; Dreher, R.; Hamilton, D.; Tufan, M.; Normand, C.; Schwenk-Ferrero, A.; Wiese, H.W.

    2008-01-01

    NUCLEONICA is a new nuclear science web portal from the European Commission's Joint Research Centre. The portal provides a customizable, integrated environment and collaboration platform for the nuclear sciences using the latest 'Web 2.0' dynamic technology. NUCLEONICA is aimed at professionals, academics and students working with radionuclides in fields as diverse as the life sciences (e.g., biology, medicine, agriculture), the earth sciences (geology, meteorology, environmental science) and the more traditional disciplines such as nuclear power, health physics and radiation protection, nuclear and radio-chemistry, and astrophysics. It is also used as a knowledge management tool to preserve nuclear knowledge built up over many decades by creating modern web-based versions of so-called legacy computer codes. (authors)

  19. The secondary metabolite bioinformatics portal

    DEFF Research Database (Denmark)

    Weber, Tilmann; Kim, Hyun Uk

    2016-01-01

    . In this context, this review gives a summary of tools and databases that currently are available to mine, identify and characterize natural product biosynthesis pathways and their producers based on ‘omics data. A web portal called Secondary Metabolite Bioinformatics Portal (SMBP at http...... analytical and chemical methods gave access to this group of compounds, nowadays genomics-based methods offer complementary approaches to find, identify and characterize such molecules. This paradigm shift also resulted in a high demand for computational tools to assist researchers in their daily work......Natural products are among the most important sources of lead molecules for drug discovery. With the development of affordable whole-genome sequencing technologies and other ‘omics tools, the field of natural products research is currently undergoing a shift in paradigms. While, for decades, mainly...

  20. Quantitative vs. subjective portal verification using digital portal images

    International Nuclear Information System (INIS)

    Bissett, Randy; Leszczynski, Konrad; Loose, Stephen; Boyko, Susan; Dunscombe, Peter

    1996-01-01

    Purpose: Off-line, computer-aided prescription (simulator) and treatment (portal) image registration using chamfer matching has been implemented on PC based viewing station. The purposes of this study were (a) to evaluate the performance of interactive anatomy and field edge extraction and subsequent registration, and (b) to compare observer's perceptions of field accuracy with measured discrepancies following anatomical registration. Methods and Materials: Prescription-treatment image pairs for 48 different patients were examined in this study. Digital prescription images were produced with the aid of a television camera and a digital frame grabber, while the treatment images were obtained directly from an on-line portal imaging system. To facilitate perception of low contrast anatomical detail, on-line portal images were enhanced with selective adaptive histogram equalization prior to extraction of anatomical edges. Following interactive extraction of anatomical and field border information by an experienced observer, the identified anatomy was registered using chamber matching. The degree of conformity between the prescription and treatment fields was quantified using several parameters, which included relative prescription field coverage and overcoverage, as well as the translational and rotational displacements as measured by chamfer matching applied to the boundaries of the two fields. These quantitative measures were compared with subjective evaluations made by four radiation oncologists. Results: All the images in this series that included a range of the most commonly seen treatment sites were registered and the conformity parameters were found. The mean treatment/prescription field coverage and overcoverage were approximately 95 and 7%, respectively before registration. The mean translational displacement in the transverse and cranio-caudal directions were 2.9 and 3.4 mm, respectively. The mean rotational displacement was approximately 2 deg. . For all

  1. Uzbekistan Radiation Portal Monitoring System

    International Nuclear Information System (INIS)

    Richardson, J; Knapp, R; Loshak, A; Yuldashev, B; Petrenko, V

    2005-01-01

    The work proposed in this presentation builds on the foundation set by the DTRA funded demonstration project begun in 2000 and completed in December of 2003. This previous work consisted of two phases whose overall objective was to install portal radiation monitors at four select ports-of-entry in Uzbekistan (Tashkent International Airport, Gisht-Kuprik (Kazakhstan border), Alat (Turkmenistan border), and Termez (Afghanistan border)) in order to demonstrate their effectiveness in preventing the illicit trafficking of nuclear materials. The objectives also included developing and demonstrating capabilities in the design, installation, operation, training, and maintenance of a radiation portal monitoring system. The system and demonstration project has proved successful in many ways. An effective working relationship among the Uzbekistan Customs Services, Uzbekistan Border Guards, and Uzbekistan Institute of Nuclear Physics has been developed. There has been unprecedented openness with the sharing of portal monitor data with Lawrence Livermore National Laboratory. The system has proved to be effective, with detection of illicit trafficking, and, at Alat, an arrest of three persons illegally transporting radioactive materials into Turkmenistan. The demonstration project has made Uzbekistan a model nonproliferation state in Central Asia and, with an expanded program, places them in a position to seal a likely transit route for illicit nuclear materials. These results will be described. In addition, this work is currently being expanded to include additional ports-of-entry in Uzbekistan. The process for deciding on which additional ports-of-entry to equip will also be described

  2. Treatment of portal hypertension caused by benign main portal vein stenosis with endovascular stent

    International Nuclear Information System (INIS)

    Huang Mingsheng; Shan Hong; Jiang Zaibo; Guan Shouhai; Zhu Kangshun; Li Zhengran; Zhou Yubin; He Bingjun

    2004-01-01

    Objective: To evaluate the value of endovascular stent in the treatment of portal hypertension caused by benign main portal vein stenosis. Methods: Portal vein stents were implanted in 6 patients with benign main portal vein stenosis (inflammatory stenosis in 3 cases, postprocedure of liver transplantation in another 3 cases). The change of portal vein pressure, the patency of portal vein, relative clinical symptoms, complications, and survival were evaluated. Results: Six metallic stents were successfully placed across the portal vein stenotic or obstructive lesions in all 6 patients. Mean portal venous pressure decreased significantly after stent implantation from (37.3 ± 4.7) cm H 2 O (1 cm H 2 O=0.098 kPa) to (18.0 ± 1.9) cm H 2 O (P<0.001). The portal blood flow was restored, and the symptoms caused by portal hypertension were eliminated. There was no severe procedure-related complication. Follow-up time was from 5 to 36 months. The portal vein remained patent during the follow-up. All patients survived except one patient who died of other complications of liver transplantation. Conclusion: Percutaneous portal vein stent placement for the treatment of the benign main portal vein stenosis is safe and effective. (authors)

  3. The effect of partial portal decompression on portal blood flow and effective hepatic blood flow in man: a prospective study.

    Science.gov (United States)

    Rosemurgy, A S; McAllister, E W; Godellas, C V; Goode, S E; Albrink, M H; Fabri, P J

    1995-12-01

    With the advent of transjugular intrahepatic porta-systemic stent shunt and the wider application of the surgically placed small diameter prosthetic H-graft portacaval shunt (HGPCS), partial portal decompression in the treatment of portal hypertension has received increased attention. The clinical results supporting the use of partial portal decompression are its low incidence of variceal rehemorrhage due to decreased portal pressures and its low rate of hepatic failure, possibly due to maintenance of blood flow to the liver. Surprisingly, nothing is known about changes in portal hemodynamics and effective hepatic blood flow following partial portal decompression. To prospectively evaluate changes in portal hemodynamics and effective hepatic blood flow brought about by partial portal decompression, the following were determined in seven patients undergoing HGPCS: intraoperative pre- and postshunt portal vein pressures and portal vein-inferior vena cava pressure gradients, intraoperative pre- and postshunt portal vein flow, and pre- and postoperative effective hepatic blood flow. With HGPCS, portal vein pressures and portal vein-inferior vena cava pressure gradients decreased significantly, although portal pressures remained above normal. In contrast to the significant decreases in portal pressures, portal vein blood flow and effective hepatic blood flow do not decrease significantly. Changes in portal vein pressures and portal vein-inferior vena cava pressure gradients are great when compared to changes in portal vein flow and effective hepatic blood flow. Reduction of portal hypertension with concomitant maintenance of hepatic blood flow may explain why hepatic dysfunction is avoided following partial portal decompression.

  4. Increased heat fluxes near a forest edge

    NARCIS (Netherlands)

    Klaassen, W; van Breugel, PB; Moors, EJ; Nieveen, JP

    2002-01-01

    Observations of sensible and latent heat flux above forest downwind of a forest edge show these fluxes to be larger than the available energy over the forest. The enhancement averages to 56 W m(-2), or 16% of the net radiation, at fetches less than 400 m, equivalent to fetch to height ratios less

  5. Increased heat fluxes near a forest edge

    NARCIS (Netherlands)

    Klaassen, W.; Breugel, van P.B.; Moors, E.J.; Nieveen, J.P.

    2002-01-01

    Observations of sensible and latent heat flux above forest downwind of a forest edge show these fluxes to be larger than the available energy over the forest. The enhancement averages to 56 W mm2, or 16 f the net radiation, at fetches less than 400 m, equivalent to fetch to height ratios less than

  6. The questions of working out radiology patterns of portal hypertension

    International Nuclear Information System (INIS)

    Vyikman, Ya.E.

    2008-01-01

    A foundation for radiological patterns of each type of portal hypertension (PH) at various stages of its development. Portal blood pressure, diameter of splenic and portal veins, volume blood flow velocity in the portal and splenic veins, incidence of hypersplenism, enlargement of the caudate lobe of the liver and gallbladder fossa are the most informative in differentiation of various forms of portal hypertension

  7. Cavernous transformation of the portal vein

    International Nuclear Information System (INIS)

    Lehotska, V.; Dostalova, K.; Durkovsky, A.; Samal, V.

    1995-01-01

    In this contribution, the authors give an account of a rare case of a cavernous transformation of the portal vein that may have originated secondarily in a proliferative hematogenous disease with a polyglobulia and thrombosis in the periferal blood count as well as development of portal hypertension of a prehepatal type. The state of hyper-coagulation in a myeloproliferative disease may have lead to a chronic thrombosis of the portal vein with a subsequent malformation of the portal vein in terms of a cavernous transformation of the portal vein. The case is an interesting one because of the discrepancy between the gravity of the thrombotic complication and slightness of the symptoms in the clinical picture. The authors point out the importance of ultrasonography and computed tomography examination following the intravenous application of a water solution of a contrast medium in a morphologic diagnosing of a rare complication of a chronic thrombotic clot of the portal vein - the cavernous transformation. (authors)

  8. [Predictive value of ultrasonography in portal hypertension].

    Science.gov (United States)

    Moreno, E; Torres, P; Trejo, C; Barra Ostoni, V; Ortega, C; Römer, H

    1991-01-01

    Portal hypertension is a common pathology in childhood and one of its most common causes is cavernomatosis of the portal vein. This obstruction causes hemodynamic changes which lead to splenomegaly and collateral circulation. Esophageal varices are one of the most important sequelae, which endanger the patient's life because of a bleeding tendency. Ecosonography helps to detect the thickening of the lesser omentum vis a vis the aortic diameter, caused by the collateral circulation. We studied 15 children presenting with portal hypertension resulting from portal vein cavernomatosis; we performed an upper GI endoscopy and abdominal ecosonography. The endoscopy revealed grade II esophageal varices in 20% of cases, the remaining 80% had grade III and grade IV. Ecosonography revealed an increased lesser omentum/aorta ratio in children with portal hypertension, compared to controls (p portal hypertension.

  9. Determining the optimal portal blood volume in a shunt before surgery in extrahepatic portal hypertension

    Directory of Open Access Journals (Sweden)

    Yurchuk Vladimir A

    2016-04-01

    Full Text Available The aim of the study: To determine the necessary shunt diameter and assess the optimal portal blood volume in a shunt in children with extrahepatic portal hypertension before the portosystemic shunt surgery. Changes in the liver hemodynamics were studied in 81 children aged from 4 to 7 years with extrahepatic portal hypertension. We established that it is necessary to calculate the shunt diameter and the blood volume in a shunt in patients with extrahepatic portal hypertension before the portosystemic shunt surgery. It allows us to preserve the hepatic portal blood flow and effectively decrease the pressure in the portal system. Portosystemic shunt surgery in patients with extrahepatic portal hypertension performed in accordance with the individualized shunt volume significantly decreases portal pressure, preserves stable hepatic hemodynamics and prevents gastro-esophageal hemorrhage.

  10. Noncirrhotic portal fibrosis after Wilms' tumor therapy

    International Nuclear Information System (INIS)

    Barnard, J.A.; Marshall, G.S.; Neblett, W.W.; Gray, G.; Ghishan, F.K.

    1986-01-01

    A 9-yr-old girl developed massive hemorrhage from esophageal varices 2 yr after combined modality therapy for Wilms' tumor. Evaluation showed a patent extrahepatic portal venous system and an elevated splenic pulp pressure. In contrast to previous reports of hepatopathy after irradiation injury, histologic sections of the liver did not demonstrate occlusion of the central veins, but rather a diffuse obliteration of intrahepatic portal venous radicles. This pattern of noncirrhotic portal fibrosis has not been described following antitumor therapy

  11. A View on Electronic Learning Portals

    OpenAIRE

    Zavaraqi, Rasoul

    2009-01-01

    Portals are less than a decade old. They have come to cover are areas of electronic services, including electronic learning. With their efficient communication and information capabilities, these portals are capable of realizing novel learning concepts such as structuralism, active and cooperative learning. The present paper endeavors to discuss the latest understanding, theories and concepts regarding E-learning portals and to review the issues and steps that should be considered in designin...

  12. Preduodenal portal vein: its surgical significance.

    Science.gov (United States)

    Makey, D A; Bowen, J C

    1978-11-01

    Preduodenal portal vein is a rare anatomical variant which may be one of many anomalies in the neonate with duodenal "atresia." Preduodenal portal vein also may be an occasional finding in an adult undergoing biliary, gastric, or pancreatic surgery. Awareness and recognition of the anomaly are essential for the avoidance of injury during such operations. We report here a symptomless patient whose preduodenal portal vein was discovered at cholecystectomy.

  13. 4D flow MR imaging of the portal venous system: a feasibility study in children

    Energy Technology Data Exchange (ETDEWEB)

    Parekh, Keyur; Rose, Michael; Popescu, Andrada; Rigsby, Cynthia K. [Ann and Robert H. Lurie Children' s Hospital of Chicago, Department of Medical Imaging, Chicago, IL (United States); Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Markl, Michael [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); McCormick School of Engineering, Northwestern University, Department of Biomedical Engineering, Chicago, IL (United States); Schnell, Susanne [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States)

    2017-02-15

    To determine the feasibility of 4D flow MRI for visualization and quantification of the portal venous haemodynamics in children and young adults. 4D flow was performed in 28 paediatric patients (median age, 8.5 years; interquartile range, 5.2-16.5), 15 with non-operated native portal system and 13 with surgically created portal shunt. Image quality assessment for 3D flow visualization and flow pattern analyses was performed. Regional 4D flow peak velocity and net flow were compared with 2D-cine phase contrast MRI (2D-PC MR) in the post-surgical patients. Mean 3D flow visualization quality score was excellent (mean ± SD, 4.2 ± 0.9) with good inter-rater agreement (κ,0.67). Image quality in children aged >10 years was better than children ≤10 years (p < 0.05). Flow pattern was defined for portal, superior mesenteric, splenic veins and splenic artery in all patients. 4D flow and 2D-PC MR peak velocity and net flow were similar with good correlation (peak velocity: 4D flow 22.2 ± 9.1 cm/s and 2D-PC MR 25.2 ± 11.2 cm/s, p = 0.46; r = 0.92, p < 0.0001; net flow: 4D flow 9.5 ± 7.4 ml/s and 2D-PC MR 10.1 ± 7.3 ml/s, p = 0.65; r = 0.81, p = 0.0007). 4D flow MRI is feasible and holds promise for the comprehensive 3D visualization and quantification of portal venous flow dynamics in children and young adults. (orig.)

  14. 4D flow MR imaging of the portal venous system: a feasibility study in children

    International Nuclear Information System (INIS)

    Parekh, Keyur; Rose, Michael; Popescu, Andrada; Rigsby, Cynthia K.; Markl, Michael; Schnell, Susanne

    2017-01-01

    To determine the feasibility of 4D flow MRI for visualization and quantification of the portal venous haemodynamics in children and young adults. 4D flow was performed in 28 paediatric patients (median age, 8.5 years; interquartile range, 5.2-16.5), 15 with non-operated native portal system and 13 with surgically created portal shunt. Image quality assessment for 3D flow visualization and flow pattern analyses was performed. Regional 4D flow peak velocity and net flow were compared with 2D-cine phase contrast MRI (2D-PC MR) in the post-surgical patients. Mean 3D flow visualization quality score was excellent (mean ± SD, 4.2 ± 0.9) with good inter-rater agreement (κ,0.67). Image quality in children aged >10 years was better than children ≤10 years (p < 0.05). Flow pattern was defined for portal, superior mesenteric, splenic veins and splenic artery in all patients. 4D flow and 2D-PC MR peak velocity and net flow were similar with good correlation (peak velocity: 4D flow 22.2 ± 9.1 cm/s and 2D-PC MR 25.2 ± 11.2 cm/s, p = 0.46; r = 0.92, p < 0.0001; net flow: 4D flow 9.5 ± 7.4 ml/s and 2D-PC MR 10.1 ± 7.3 ml/s, p = 0.65; r = 0.81, p = 0.0007). 4D flow MRI is feasible and holds promise for the comprehensive 3D visualization and quantification of portal venous flow dynamics in children and young adults. (orig.)

  15. Quantum net dynamics

    International Nuclear Information System (INIS)

    Finkelstein, D.

    1989-01-01

    The quantum net unifies the basic principles of quantum theory and relativity in a quantum spacetime having no ultraviolet infinities, supporting the Dirac equation, and having the usual vacuum as a quantum condensation. A correspondence principle connects nets to Schwinger sources and further unifies the vertical structure of the theory, so that the functions of the many hierarchic levels of quantum field theory (predicate algebra, set theory, topology,hor-ellipsis, quantum dynamics) are served by one in quantum net dynamics

  16. Web-based Service Portal in Healthcare

    Science.gov (United States)

    Silhavy, Petr; Silhavy, Radek; Prokopova, Zdenka

    Information delivery is one the most important task in healthcare. The growing sector of electronic healthcare has an important impact on the information delivery. There are two basic approaches towards information delivering. The first is web portal and second is touch-screen terminal. The aim of this paper is to investigate the web-based service portal. The most important advantage of web-based portal in the field of healthcare is an independent access for patients. This paper deals with the conditions and frameworks for healthcare portals

  17. Programming NET Web Services

    CERN Document Server

    Ferrara, Alex

    2007-01-01

    Web services are poised to become a key technology for a wide range of Internet-enabled applications, spanning everything from straight B2B systems to mobile devices and proprietary in-house software. While there are several tools and platforms that can be used for building web services, developers are finding a powerful tool in Microsoft's .NET Framework and Visual Studio .NET. Designed from scratch to support the development of web services, the .NET Framework simplifies the process--programmers find that tasks that took an hour using the SOAP Toolkit take just minutes. Programming .NET

  18. Game Coloured Petri Nets

    DEFF Research Database (Denmark)

    Westergaard, Michael

    2006-01-01

    This paper introduces the notion of game coloured Petri nets. This allows the modeler to explicitly model what parts of the model comprise the modeled system and what parts are the environment of the modeled system. We give the formal definition of game coloured Petri nets, a means of reachability...... analysis of this net class, and an application of game coloured Petri nets to automatically generate easy-to-understand visualizations of the model by exploiting the knowledge that some parts of the model are not interesting from a visualization perspective (i.e. they are part of the environment...

  19. A user-oriented model for global enterprise portal design

    NARCIS (Netherlands)

    Feng, X.; Ehrenhard, Michel Léon; Hicks, Jeff; Maathuis, Stephanus Johannes; Maathuis, S.J.; Hou, Y.

    2010-01-01

    Enterprise portals collect and synthesise information from various systems to deliver personalised and highly relevant information to users. Enterprise portals' design and applications are widely discussed in the literature; however, the implications of portal design in a global networked

  20. Patient portals - An online tool for your health

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/patientinstructions/000880.htm Patient portals - an online tool for your health To ... is private and secure. What is in a Patient Portal? With a patient portal, you can: Make ...

  1. Portal Web 2.0

    OpenAIRE

    Barba Hidalgo, José Manuel

    2008-01-01

    El tema que es tracta en aquest projecte gira al voltant del concepte Web 2.0. Després d’una introducció on es comenten les principals característiques que defineixen el conjunt d’aplicacions agrupades al voltant d’aquesta filosofia, s’analitzen diferents entorns de desenvolupament d’aplicacions Web, amb l’objectiu de crear un portal que segueixi els principis Web 2.0. El resultat de l’estudi presenta a Ruby on Rails com un ferm candidat, això fa que es procedeixi a estudiar aq...

  2. Portal web para comunicaciones seguras

    OpenAIRE

    Jurado Villalobos, Rodrigo

    2015-01-01

    Proyecto teórico-práctico de investigación, enfocado a obtener un mayor conocimiento del funcionamiento de los protocolos y funciones de seguridad criptógrafica así como explorar las limitaciones y buscar nuevas vías de implementar la seguridad de las comunicaciones a través del desarrollo de una aplicación que dé uso en un entorno “real” de estos protocolos de seguridad. Dicha aplicación consistirá en un portal web de mensajería entre usuarios que empleará sistemas criptográficos tanto en el...

  3. Doppler US evaluation of the hypertensive portal system

    International Nuclear Information System (INIS)

    Needleman, L.; Kurtz, A.B.; Bezzi, M.; Rifkin, M.D.; Pasto, M.E.; Pennell, R.G.; Baltarowich, O.H.; Goldberg, B.B.

    1986-01-01

    In patients with known portal hypertension, pulsed Doppler US was used for qualitative and directional evaluation of flow in the portal venous system and collateral vessels. Most patients had normal hepatopetal flow. Doppler US revealed the following abnormal blood flow patterns: hepatofugal portal flow, bidirectional portal flow, intrahepatic portal shunting, flow in portasystemic collaterals, and hepatic vein obstruction. Doppler US can provide important clinical information in the evaluation of portal hypertension

  4. Portal in the power sector - it is vision or reality?

    International Nuclear Information System (INIS)

    Hornak, L.

    2004-01-01

    The goal of the presentation is to introduce the portal solutions, to describe the types, characteristic features and abilities of the portal and to define required attributes of the portal in the power segment. The author will try to answer the questions whether such portal exists at the present time, what is needed in order to implement the portal and how to do the portal maintenance and management

  5. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt

    1991-01-01

    This paper describes how Coloured Petri Nets (CP-nets) have been developed — from being a promising theoretical model to being a full-fledged language for the design, specification, simulation, validation and implementation of large software systems (and other systems in which human beings and...

  6. Net zero water

    CSIR Research Space (South Africa)

    Lindeque, M

    2013-01-01

    Full Text Available the national grid. The unfortunate situation with water is that there is no replacement technology for water. Water can be supplied from many different sources. A net zero energy development will move closer to a net zero water development by reducing...

  7. Construction of monophase nets

    International Nuclear Information System (INIS)

    Suarez A, Jose Antonio

    1996-01-01

    The paper refers to the use of monophase loads in commercial residential urbanizations and in small industries, for this reason it is considered unnecessary the construction of three-phase nets. The author makes a historical recount of these nets in Bogota, his capacities, uses and energy savings

  8. Fusion through the NET

    International Nuclear Information System (INIS)

    Spears, B.

    1987-01-01

    The paper concerns the next generation of fusion machines which are intended to demonstrate the technical viability of fusion. In Europe, the device that will follow on from JET is known as NET - the Next European Torus. If the design programme for NET proceeds, Europe could start to build the machine in 1994. The present JET programme hopes to achieve breakeven in the early 1990's. NET hopes to reach ignition in the next century, and so lay the foundation for a demonstration reactor. A description is given of the technical specifications of the components of NET, including: the first wall, the divertors to protect the wall, the array of magnets that provide the fields containing the plasma, the superconducting magnets, and the shield of the machine. NET's research programme is briefly outlined, including the testing programme to optimise conditions in the machine to achieve ignition, and its safety work. (U.K.)

  9. CARBON STORAGE AND FLUXES IN PONDEROSA PINE AT DIFFERENT SUCCESSIONAL STAGES

    Science.gov (United States)

    We compared carbon storage and fluxes in young and old ponderosa pine stands in Oregon, including plant and soil storage, net primary productivity, respiration fluxes, and eddy flux estimates of net ecosystem exchange. The young site (Y site) was previously an old-growth pondero...

  10. Factors Affecting Faculty Web Portal Usability

    Science.gov (United States)

    Bringula, Rex P.; Basa, Roselle S.

    2011-01-01

    The study investigated the factors that might significantly affect web portal usability. Results of the study were intended to serve as inputs for faculty web portal development of the University of the East-Manila. Descriptive statistics utilized questionnaire data from 82 faculty members. The data showed that most of the respondents were…

  11. Portal circulation aneurysms: two case reviews

    International Nuclear Information System (INIS)

    Perret, W. L.; Silva, A de.; Elzarka, A.; Schelleman, A.

    2007-01-01

    Venous aneurysms of the superior mesenteric vein and portal vein are an uncommon occurrence and often an incidental finding. They can also be associated with hepatocellular disease and portal hypertension. We present CT and ultrasound findings of these entities. The management of venous aneurysms is generally conservative with serial imaging

  12. Optimization of portal placement for endoscopic calcaneoplasty

    NARCIS (Netherlands)

    van Sterkenburg, Maayke N.; Groot, Minke; Sierevelt, Inger N.; Spennacchio, Pietro A.; Kerkhoffs, Gino M. M. J.; van Dijk, C. Niek

    2011-01-01

    The purpose of our study was to determine an anatomic landmark to help locate portals in endoscopic calcaneoplasty. The device for optimal portal placement (DOPP) was developed to measure the distance from the distal fibula tip to the calcaneus (DFC) in 28 volunteers to determine the location of the

  13. Percutaneous transhepatic portal vein stenting in a patient with benign non-transplant postoperative portal vein stenosis: A case report

    OpenAIRE

    Madhusudhan, KS; Agrawal, Nikhil; Srivastava, Deep N; Pal, Sujoy; Gupta, Arun K

    2013-01-01

    Extrahepatic portal vein stenosis is caused by a variety of benign and malignant diseases and results in development of symptoms due to portal hypertension. Benign post-surgical adhesions causing portal vein stenosis in non-transplant population is an uncommon etiology of portal hypertension. Endovascular treatment of such patients with angioplasty and stenting is uncommonly reported in literature. We report a case of portal hypertension caused by benign postoperative portal vein fibrosis, su...

  14. Isocurvature constraints on portal couplings

    Energy Technology Data Exchange (ETDEWEB)

    Kainulainen, Kimmo; Nurmi, Sami; Vaskonen, Ville [Department of Physics, University of Jyväskylä, P.O.Box 35 (YFL), FI-40014 University of Jyväskylä (Finland); Tenkanen, Tommi; Tuominen, Kimmo, E-mail: kimmo.kainulainen@jyu.fi, E-mail: sami.t.nurmi@jyu.fi, E-mail: tommi.tenkanen@helsinki.fi, E-mail: kimmo.i.tuominen@helsinki.fi, E-mail: ville.vaskonen@jyu.fi [Department of Physics, University of Helsinki P.O. Box 64, FI-00014, Helsinki (Finland)

    2016-06-01

    We consider portal models which are ultraweakly coupled with the Standard Model, and confront them with observational constraints on dark matter abundance and isocurvature perturbations. We assume the hidden sector to contain a real singlet scalar s and a sterile neutrino ψ coupled to s via a pseudoscalar Yukawa term. During inflation, a primordial condensate consisting of the singlet scalar s is generated, and its contribution to the isocurvature perturbations is imprinted onto the dark matter abundance. We compute the total dark matter abundance including the contributions from condensate decay and nonthermal production from the Standard Model sector. We then use the Planck limit on isocurvature perturbations to derive a novel constraint connecting dark matter mass and the singlet self coupling with the scale of inflation: m {sub DM}/GeV ∼< 0.2λ{sub s}{sup 3/8} ( H {sub *}/10{sup 11} GeV){sup −3/2}. This constraint is relevant in most portal models ultraweakly coupled with the Standard Model and containing light singlet scalar fields.

  15. Ultrasonography for Noninvasive Assessment of Portal Hypertension.

    Science.gov (United States)

    Maruyama, Hitoshi; Yokosuka, Osamu

    2017-07-15

    Portal hypertension is a major pathophysiology in patients with cirrhosis. Portal pressure is the gold standard to evaluate the severity of portal hypertension, and radiological intervention is the only procedure for pressure measurement. Ultrasound (US) is a simple and noninvasive imaging modality available worldwide. B-mode imaging allows broad applications for patients to detect and characterize chronic liver diseases and focal hepatic lesions. The Doppler technique offers real-time observation of blood flow with qualitative and quantitative assessments, and the application of microbubble-based contrast agents has improved the detectability of peripheral blood flow. In addition, elastography for the liver and spleen covers a wider field beyond the original purpose of fibrosis assessment. These developments enhance the practical use of US in the evaluation of portal hemodynamic abnormalities. This article reviews the recent progress of US in the assessment of portal hypertension.

  16. Idiopathic noncirrhotic portal hypertension: current perspectives.

    Science.gov (United States)

    Riggio, Oliviero; Gioia, Stefania; Pentassuglio, Ilaria; Nicoletti, Valeria; Valente, Michele; d'Amati, Giulia

    2016-01-01

    The term idiopathic noncirrhotic portal hypertension (INCPH) has been recently proposed to replace terms, such as hepatoportal sclerosis, idiopathic portal hypertension, incomplete septal cirrhosis, and nodular regenerative hyperplasia, used to describe patients with a hepatic presinusoidal cause of portal hypertension of unknown etiology, characterized by features of portal hypertension (esophageal varices, nonmalignant ascites, porto-venous collaterals), splenomegaly, patent portal, and hepatic veins and no clinical and histological signs of cirrhosis. Physicians should learn to look for this condition in a number of clinical settings, including cryptogenic cirrhosis, a disease known to be associated with INCPH, drug administration, and even chronic alterations in liver function tests. Once INCPH is clinically suspected, liver histology becomes mandatory for the correct diagnosis. However, pathologists should be familiar with the histological features of INCPH, especially in cases in which histology is not only requested to exclude liver cirrhosis.

  17. Enterprise Information Management with Plone Portals

    Directory of Open Access Journals (Sweden)

    Marcello Peixoto Bax

    2009-05-01

    Full Text Available The article shows that it is possible to implement a corporate portal using open source software, in an integrated manner with the proprietary MS Windows environment. As it is the real scenario in the vast majority of businesses and organizations today, a portal that meets these specific requirements is highly representative, mainly because MS Windows integration in the client environment (not in the server is not trivial for an open source portal. The paper shows that, by deploying a portal in this context the company considerably moves forward regarding information management. To show this, the article focuses on the key positive aspects arising from the deployment of a intranet / extranet portal in that context, i.e., MS Windows integration; editing with MS Office or other similar applications; shared editing control (with check-in and check-out; universal web access; and the use of metadata and workflow.

  18. Customizable scientific web portal for fusion research

    International Nuclear Information System (INIS)

    Abla, G.; Kim, E.N.; Schissel, D.P.; Flanagan, S.M.

    2010-01-01

    Web browsers have become a major application interface for participating in scientific experiments such as those in magnetic fusion. The recent advances in web technologies motivated the deployment of interactive web applications with rich features. In the scientific world, web applications have been deployed in portal environments. When used in a scientific research environment, such as fusion experiments, web portals can present diverse sources of information in a unified interface. However, the design and development of a scientific web portal has its own challenges. One such challenge is that a web portal needs to be fast and interactive despite the high volume of information and number of tools it presents. Another challenge is that the visual output of the web portal must not be overwhelming to the end users, despite the high volume of data generated by fusion experiments. Therefore, the applications and information should be customizable depending on the needs of end users. In order to meet these challenges, the design and implementation of a web portal needs to support high interactivity and user customization. A web portal has been designed to support the experimental activities of DIII-D researchers worldwide by providing multiple services, such as real-time experiment status monitoring, diagnostic data access and interactive data visualization. The web portal also supports interactive collaborations by providing a collaborative logbook, shared visualization and online instant messaging services. The portal's design utilizes the multi-tier software architecture and has been implemented utilizing web 2.0 technologies, such as AJAX, Django, and Memcached, to develop a highly interactive and customizable user interface. It offers a customizable interface with personalized page layouts and list of services, which allows users to create a unique, personalized working environment to fit their own needs and interests. This paper describes the software

  19. Customizable scientific web portal for fusion research

    Energy Technology Data Exchange (ETDEWEB)

    Abla, G., E-mail: abla@fusion.gat.co [General Atomics, P.O. Box 85608, San Diego, CA (United States); Kim, E.N.; Schissel, D.P.; Flanagan, S.M. [General Atomics, P.O. Box 85608, San Diego, CA (United States)

    2010-07-15

    Web browsers have become a major application interface for participating in scientific experiments such as those in magnetic fusion. The recent advances in web technologies motivated the deployment of interactive web applications with rich features. In the scientific world, web applications have been deployed in portal environments. When used in a scientific research environment, such as fusion experiments, web portals can present diverse sources of information in a unified interface. However, the design and development of a scientific web portal has its own challenges. One such challenge is that a web portal needs to be fast and interactive despite the high volume of information and number of tools it presents. Another challenge is that the visual output of the web portal must not be overwhelming to the end users, despite the high volume of data generated by fusion experiments. Therefore, the applications and information should be customizable depending on the needs of end users. In order to meet these challenges, the design and implementation of a web portal needs to support high interactivity and user customization. A web portal has been designed to support the experimental activities of DIII-D researchers worldwide by providing multiple services, such as real-time experiment status monitoring, diagnostic data access and interactive data visualization. The web portal also supports interactive collaborations by providing a collaborative logbook, shared visualization and online instant messaging services. The portal's design utilizes the multi-tier software architecture and has been implemented utilizing web 2.0 technologies, such as AJAX, Django, and Memcached, to develop a highly interactive and customizable user interface. It offers a customizable interface with personalized page layouts and list of services, which allows users to create a unique, personalized working environment to fit their own needs and interests. This paper describes the software

  20. Customizable Scientific Web Portal for Fusion Research

    Energy Technology Data Exchange (ETDEWEB)

    Abla, G; Kim, E; Schissel, D; Flannagan, S [General Atomics, San Diego (United States)

    2009-07-01

    The Web browser has become one of the major application interfaces for remotely participating in magnetic fusion experiments. Recently in other areas, web portals have begun to be deployed. These portals are used to present very diverse sources of information in a unified way. While a web portal has several benefits over other software interfaces, such as providing single point of access for multiple computational services, and eliminating the need for client software installation, the design and development of a web portal has unique challenges. One of the challenges is that a web portal needs to be fast and interactive despite a high volume of tools and information that it presents. Another challenge is the visual output on the web portal often is overwhelming due to the high volume of data generated by complex scientific instruments and experiments; therefore the applications and information should be customizable depending on the needs of users. An appropriate software architecture and web technologies can meet these problems. A web-portal has been designed to support the experimental activities of DIII-D researchers worldwide. It utilizes a multi-tier software architecture, and web 2.0 technologies, such as AJAX, Django, and Memcached, to develop a highly interactive and customizable user interface. It offers a customizable interface with personalized page layouts and list of services for users to select. The users can create a unique personalized working environment to fit their own needs and interests. Customizable services are: real-time experiment status monitoring, diagnostic data access, interactive data visualization. The web-portal also supports interactive collaborations by providing collaborative logbook, shared visualization and online instant message services. Furthermore, the web portal will provide a mechanism to allow users to create their own applications on the web portal as well as bridging capabilities to external applications such as

  1. Customisable Scientific Web Portal for Fusion Research

    Energy Technology Data Exchange (ETDEWEB)

    Abla, G; Kim, E; Schissel, D; Flannagan, S [General Atomics, San Diego (United States)

    2009-07-01

    The Web browser has become one of the major application interfaces for remotely participating in magnetic fusion. Web portals are used to present very diverse sources of information in a unified way. While a web portal has several benefits over other software interfaces, such as providing single point of access for multiple computational services, and eliminating the need for client software installation, the design and development of a web portal has unique challenges. One of the challenges is that a web portal needs to be fast and interactive despite a high volume of tools and information that it presents. Another challenge is the visual output on the web portal often is overwhelming due to the high volume of data generated by complex scientific instruments and experiments; therefore the applications and information should be customizable depending on the needs of users. An appropriate software architecture and web technologies can meet these problems. A web-portal has been designed to support the experimental activities of DIII-D researchers worldwide. It utilizes a multi-tier software architecture, and web 2.0 technologies, such as AJAX, Django, and Memcached, to develop a highly interactive and customizable user interface. It offers a customizable interface with personalized page layouts and list of services for users to select. Customizable services are: real-time experiment status monitoring, diagnostic data access, interactive data visualization. The web-portal also supports interactive collaborations by providing collaborative logbook, shared visualization and online instant message services. Furthermore, the web portal will provide a mechanism to allow users to create their own applications on the web portal as well as bridging capabilities to external applications such as Twitter and other social networks. In this series of slides, we describe the software architecture of this scientific web portal and our experiences in utilizing web 2.0 technologies. A

  2. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Gustavsen, Arild

    2010-01-01

    and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...

  3. Getting to Net Zero

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-01

    The technology necessary to build net zero energy buildings (NZEBs) is ready and available today, however, building to net zero energy performance levels can be challenging. Energy efficiency measures, onsite energy generation resources, load matching and grid interaction, climatic factors, and local policies vary from location to location and require unique methods of constructing NZEBs. It is recommended that Components start looking into how to construct and operate NZEBs now as there is a learning curve to net zero construction and FY 2020 is just around the corner.

  4. Pro NET Best Practices

    CERN Document Server

    Ritchie, Stephen D

    2011-01-01

    Pro .NET Best Practices is a practical reference to the best practices that you can apply to your .NET projects today. You will learn standards, techniques, and conventions that are sharply focused, realistic and helpful for achieving results, steering clear of unproven, idealistic, and impractical recommendations. Pro .NET Best Practices covers a broad range of practices and principles that development experts agree are the right ways to develop software, which includes continuous integration, automated testing, automated deployment, and code analysis. Whether the solution is from a free and

  5. PSUP: A Planetary SUrface Portal

    Science.gov (United States)

    Poulet, F.; Quantin-Nataf, C.; Ballans, H.; Dassas, K.; Audouard, J.; Carter, J.; Gondet, B.; Lozac'h, L.; Malapert, J.-C.; Marmo, C.; Riu, L.; Séjourné, A.

    2018-01-01

    The large size and complexity of planetary data acquired by spacecraft during the last two decades create a demand within the planetary community for access to the archives of raw and high level data and for the tools necessary to analyze these data. Among the different targets of the Solar System, Mars is unique as the combined datasets from the Viking, Mars Global Surveyor, Mars Odyssey, Mars Express and Mars Reconnaissance Orbiter missions provide a tremendous wealth of information that can be used to study the surface of Mars. The number and the size of the datasets require an information system to process, manage and distribute data. The Observatories of Paris Sud (OSUPS) and Lyon (OSUL) have developed a portal, called PSUP (Planetary SUrface Portal), for providing users with efficient and easy access to data products dedicated to the Martian surface. The objectives of the portal are: 1) to allow processing and downloading of data via a specific application called MarsSI (Martian surface data processing Information System); 2) to provide the visualization and merging of high level (image, spectral, and topographic) products and catalogs via a web-based user interface (MarsVisu), and 3) to distribute some of these specific high level data with an emphasis on products issued by the science teams of OSUPS and OSUL. As the MarsSI service is extensively described in a companion paper (Quantin-Nataf et al., companion paper, submitted to this special issue), the present paper focus on the general architecture and the functionalities of the web-based user interface MarsVisu. This service provides access to many data products for Mars: albedo, mineral and thermal inertia global maps from spectrometers; mosaics from imagers; image footprints and rasters from the MarsSI tool; high level specific products (defined as catalogs or vectors). MarsVisu can be used to quickly assess the visualized processed data and maps as well as identify areas that have not been mapped yet

  6. The feasible study of vasodilators in portal vein targeting infusion for treating portal hypertension

    International Nuclear Information System (INIS)

    Wu Hanping; Liang Huiming; Zheng Chuansheng; Feng Gansheng

    2002-01-01

    Objective: To find out the ideal portal vein tar getting injection routes for portal hypertension treatment. Methods: 28 cirrhotic rat models with portal hypertension induced by CCl 4 were divided into 4 groups: inferior caval vein injection group, portal vein injection group, hepatic artery injection group, spleen injection group. The changes in portal vein pressure (PVP), inferior caval vein pressure (ICVP), mean artery pressure (MAP) and heart rate (HR) were monitored before and after prazosin injection. Results: After intra-portal, intra-hepatic arterial or spleen injection of prazosin, larger decrease in PVP and lesser effects on MAP than intravenous injection had been induced. The effect on HR showed no difference among these four groups. Conclusions: Hepatic artery and spleen prazosin administration have the same advantages on treatment of portal hypertension as those of intra-portal infusion, that is the greater decrease on portal vein pressure, the lesser effects on systemic hemodynamics. Vasodilation drugs for hepatic artery infusion through percutaneous port catheter system by hepatic artery implantation would be an ideal method for portal hypertension treatment

  7. PhysioNet

    Data.gov (United States)

    U.S. Department of Health & Human Services — The PhysioNet Resource is intended to stimulate current research and new investigations in the study of complex biomedical and physiologic signals. It offers free...

  8. NetSig

    DEFF Research Database (Denmark)

    Horn, Heiko; Lawrence, Michael S; Chouinard, Candace R

    2018-01-01

    Methods that integrate molecular network information and tumor genome data could complement gene-based statistical tests to identify likely new cancer genes; but such approaches are challenging to validate at scale, and their predictive value remains unclear. We developed a robust statistic (Net......Sig) that integrates protein interaction networks with data from 4,742 tumor exomes. NetSig can accurately classify known driver genes in 60% of tested tumor types and predicts 62 new driver candidates. Using a quantitative experimental framework to determine in vivo tumorigenic potential in mice, we found that Net......Sig candidates induce tumors at rates that are comparable to those of known oncogenes and are ten-fold higher than those of random genes. By reanalyzing nine tumor-inducing NetSig candidates in 242 patients with oncogene-negative lung adenocarcinomas, we find that two (AKT2 and TFDP2) are significantly amplified...

  9. Blanket testing in NET

    International Nuclear Information System (INIS)

    Chazalon, M.; Daenner, W.; Libin, B.

    1989-01-01

    The testing stages in NET for the performance assessment of the various breeding blanket concepts developed at the present time in Europe for DEMO (LiPb and ceramic blankets) and the requirements upon NET to perform these tests are reviewed. Typical locations available in NET for blanket testing are the central outboard segments and the horizontal ports of in-vessel sectors. These test positions will be connectable with external test loops. The number of test loops (helium, water, liquid metal) will be such that each major class of blankets can be tested in NET. The test positions, the boundary conditions and the external test loops are identified and the requirements for test blankets are summarized (author). 6

  10. Programming NET 35

    CERN Document Server

    Liberty, Jesse

    2009-01-01

    Bestselling author Jesse Liberty and industry expert Alex Horovitz uncover the common threads that unite the .NET 3.5 technologies, so you can benefit from the best practices and architectural patterns baked into the new Microsoft frameworks. The book offers a Grand Tour" of .NET 3.5 that describes how the principal technologies can be used together, with Ajax, to build modern n-tier and service-oriented applications. "

  11. NET SALARY ADJUSTMENT

    CERN Multimedia

    Finance Division

    2001-01-01

    On 15 June 2001 the Council approved the correction of the discrepancy identified in the net salary adjustment implemented on 1st January 2001 by retroactively increasing the scale of basic salaries to achieve the 2.8% average net salary adjustment approved in December 2000. We should like to inform you that the corresponding adjustment will be made to your July salary. Full details of the retroactive adjustments will consequently be shown on your pay slip.

  12. CERN & Society launches donation portal

    CERN Multimedia

    Cian O'Luanaigh

    2014-01-01

    The CERN & Society programme brings together projects in the areas of education and outreach, innovation and knowledge exchange, and culture and arts, that spread the CERN spirit of scientific curiosity for the inspiration and benefit of society. Today, CERN & Society is launching its "giving" website – a portal to allow donors to contribute to various projects and forge new relationships with CERN.   "The CERN & Society initiative in its embryonic form began almost three years ago, with the feeling that the laboratory could play a bigger role for the benefit of society," says Matteo Castoldi, Head of the CERN Development Office, who, with his team, is seeking supporters and ambassadors for the CERN & Society initiative. "The concept is not completely new – in some sense it is embedded in CERN’s DNA, as the laboratory helps society by creating knowledge and new technologies – but we would like to d...

  13. Portal hydatid with secondary cavernomatosis.

    Science.gov (United States)

    Rodríguez Sanz, Mª Belén; Roldán Cuena, Mª Del Mar; Blanco Álvarez, Carlos Alberto; Sánchez Jiménez, Raúl

    2017-03-01

    The hydatid cyst is a parasitic infection included within the category of zoonoses, in which there exists a direct or indirect relation with animals, particularly with dogs. We report a clinical case of a patient who has undergone surgery of hydatid cyst in the right hepatic lobe. Seven years later the patient presents hydatid cyst in portal vein with secondary cavernomatosis, which is a rare complication. There are few cases described in the literature. The symtomatology presented by hydatid cyst is variable and the diagnosis is made by ultrasonography, TC and/or RNM. The treatment of choice is the surgical removal of the cyst, prior to surgery Albendazol must be administered for 1-2 weeks and be maintained for 4 more weeks after surgery.

  14. BSD Portals for LINUX 2.0

    Science.gov (United States)

    McNab, A. David; woo, Alex (Technical Monitor)

    1999-01-01

    Portals, an experimental feature of 4.4BSD, extend the file system name space by exporting certain open () requests to a user-space daemon. A portal daemon is mounted into the file name space as if it were a standard file system. When the kernel resolves a pathname and encounters a portal mount point, the remainder of the path is passed to the portal daemon. Depending on the portal "pathname" and the daemon's configuration, some type of open (2) is performed. The resulting file descriptor is passed back to the kernel which eventually returns it to the user, to whom it appears that a "normal" open has occurred. A proxy portalfs file system is responsible for kernel interaction with the daemon. The overall effect is that the portal daemon performs an open (2) on behalf of the kernel, possibly hiding substantial complexity from the calling process. One particularly useful application is implementing a connection service that allows simple scripts to open network sockets. This paper describes the implementation of portals for LINUX 2.0.

  15. The Seed Proteome Web Portal

    Directory of Open Access Journals (Sweden)

    Marc eGalland

    2012-06-01

    Full Text Available The Seed Proteome Web Portal (SPWP; http://www.seedproteome.com/ gives access to information both on quantitative seed proteomic data and on seed-related protocols. Firstly, the SPWP provides access to the 475 different Arabidopsis seed proteins annotated from 2 dimensional electrophoresis (2DE maps. Quantitative data are available for each protein according to their accumulation profile during the germination process. These proteins can be retrieved either in list format or directly on scanned 2DE maps. These proteomic data reveal that 40% of seed proteins maintain a stable abundance over germination, up to radicle protrusion. During sensu stricto germination (24 h upon imbibition about 50% of the proteins display quantitative variations, exhibiting an increased abundance (35% or a decreasing abundance (15%. Moreover, during radicle protrusion (24 h to 48 h upon imbibition, 41% proteins display quantitative variations with an increased (23% or a decreasing abundance (18%. In addition, an analysis of the seed proteome revealed the importance of protein post-translational modifications as demonstrated by the poor correlation (r2 = 0.29 between the theoretical (predicted from Arabidopsis genome and the observed protein isoelectric points. Secondly, the SPWP is a relevant technical resource for protocols specifically dedicated to Arabidopsis seed proteome studies. Concerning 2D electrophoresis, the user can find efficient procedures for sample preparation, electrophoresis coupled with gel analysis and protein identification by mass spectrometry, which we have routinely used during the last 12 years. Particular applications such as the detection of oxidized proteins or de novo synthetized proteins radiolabeled by [35S]-methionine are also given in great details. Future developments of this portal will include proteomic data from studies such as dormancy release and protein turnover through de novo protein synthesis analyses during germination.

  16. Patient portals and broadband internet inequality.

    Science.gov (United States)

    Perzynski, Adam T; Roach, Mary Joan; Shick, Sarah; Callahan, Bill; Gunzler, Douglas; Cebul, Randall; Kaelber, David C; Huml, Anne; Thornton, John Daryl; Einstadter, Douglas

    2017-09-01

    Patient portals have shown potential for increasing health care quality and efficiency. Internet access and other factors influencing patient portal use could worsen health disparities. Observational study of adults with 1 or more visits to the outpatient clinics of an urban public health care system from 2012 to 2015. We used mixed effects logistic regression to evaluate the association between broadband internet access and (1) patient portal initiation (whether a patient logged in at least 1 time) and (2) messaging, controlling for demographic and neighborhood characteristics. There were 243 248 adults with 1 or more visits during 2012-2015 and 70 835 (29.1%) initiated portal use. Portal initiation was 34.1% for whites, 23.4% for blacks, and 23.8% for Hispanics, and was lower for Medicaid (26.5%), Medicare (23.4%), and uninsured patients (17.4%) than commercially insured patients (39.3%). In multivariate analysis, both initiation of portal use (odds ratio [OR] = 1.24 per quintile, 95% confidence interval [CI], 1.23-1.24, P  internet access. The majority of adults with outpatient visits to a large urban health care system did not use the patient portal, and initiation of use was lower for racial and ethnic minorities, persons of lower socioeconomic status, and those without neighborhood broadband internet access. These results suggest the emergence of a digital divide in patient portal use. Given the scale of investment in patient portals and other internet-dependent health information technologies, efforts are urgently needed to address this growing inequality. © The Author 2017. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  17. Benign hepatic portal venous gas following caustic ingestion

    International Nuclear Information System (INIS)

    Lewin, Maite; Tubiana, Jean-Michel; Pocard, Marc; Caplin, Scott; Parc, Rolland; Blain, Antoine

    2002-01-01

    Hepatic portal vein gas has been documented in numerous conditions and is traditionally regarded as a poor prognostic sign. There are, however, several reports of portal vein gas with a benign course. We report the first case of transient hepatic portal vein gas secondary to the ingestion of a caustic substance. The literature of hepatic portal vein gas in benign disease is reviewed. (orig.)

  18. Radionuclide splenoportography in patients with portal hypertension

    International Nuclear Information System (INIS)

    Kuriya, Kouji; Nagamachi, Shigeki; Hoshi, Hiroaki; Ohnishi, Takashi; Jinnouchi, Masashi; Futami, Sigemi; Yoshida, Akira; Watanabe, Katsuji

    1991-01-01

    Splenoportography using 99m Tc-pertechnetate was performed in 18 patients with portal hypertension. 99m Tc pertechnetate (370 MBq) was directly injected into the spleen. Co-lateral circulation of portal vein was observed in 13 of 18 patients (72%). L/H ratio was also calculated by the time activity curve of dynamic images. L/H ratio was significantly lower (p<0.05) in patients with colateral vessels and severe esophageal varix. Radionuclide splenography was an useful method for evaluating hemodynamics of portal vein. (author)

  19. Predictive model of portal venous system thrombosis in cirrhotic portal hypertensive patients after splenectomy

    OpenAIRE

    He, Shasha; He, Fangping

    2015-01-01

    Objective: This study is to investigate the risk factors of portal venous system thrombosis (PVT) in patients with cirrhotic portal hypertension after splenectomy and to establish a Logistic regression prediction model. Methods: A total of 119 patients with cirrhotic portal hypertension were enrolled. Their clinical data was retrospectively analyzed. They were divided into PVT group (n = 18) and non-PVT group (n = 101). One-way analysis and multivariate Logistic regression analysis were perfo...

  20. Macronodular hepatic tuberculosis associated with portal vein thrombosis and portal hypertension

    International Nuclear Information System (INIS)

    Venkatesh, S.K.; Tan, L.K.A.; Siew, E.P.Y.; Putti, T.C.

    2005-01-01

    Tuberculosis (TB) of the liver is usually associated with miliary spread. Macronodular TB of the liver is rare. A case of macronodular TB of the liver in a 31-year-old woman causing portal vein thrombosis and portal hypertension is presented. Ultrasound and CT appearances are described. There was coexistent ileo-caecal TB with extensive mesenteric and retroperitoneal lymphadenopathy. Macronodular TB should be considered in the differential diagnosis when a patient presents with multiple calcified masses in the liver with portal vein thrombosis and portal hypertension. Copyright (2005) Blackwell Science Pty Ltd

  1. Analysis of Dynamic Characteristics of Portal Frame with Variable Section

    OpenAIRE

    Hao Jianing

    2016-01-01

    Combined with a portal frame design, by the use of finite element software ANSYS, the finite element model of single specimens of portal rigid frame and the overall portal rigid frame building are established. portal rigid frame’s beam and column is variable cross section. Through the modal analysis, comparative analysis of the frequency and vibration type of the radiolabeling specimens and finite element model of the whole, for the further development of variable cross-section portal rigid f...

  2. BOREAS TF-04 CO2 and CH4 Chamber Flux Data from the SSA

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: Contains fluxes of carbon dioxide and methane across the soil-air interface in four ages of jack pine forest at the Southern Study Area. Gross and net flux...

  3. Federal High End Computing (HEC) Information Portal

    Data.gov (United States)

    Networking and Information Technology Research and Development, Executive Office of the President — This portal provides information about opportunities to engage in U.S. Federal government high performance computing activities, including supercomputer use,...

  4. Autonomic dysfunction in cirrhosis and portal hypertension

    DEFF Research Database (Denmark)

    Dümcke, Christine Winkler; Møller, Søren

    2008-01-01

    Liver cirrhosis and portal hypertension are frequently associated with signs of circulatory dysfunction and peripheral polyneuropathy, which includes defects of the autonomic nervous system. Autonomic dysfunction, which is seen in both alcoholic and non-alcoholic liver cirrhosis and increases...

  5. Scintiphotosplenoportography in patients with portal hypertension

    International Nuclear Information System (INIS)

    Aijaz, A.

    1990-01-01

    Scintiphotosplenoportograpy (SSP) was performed in five normals and 25 patients with portal hypertension using Tc-99m tin colloid. 12 patients were cirrhotic and 13 had idiopathic portal hypertension (IPH). Analogue and fast frame dynamic studies were performed and subsequently processed. Intra hepatic shunt index in cirrhotics was significantly different from the IPH group. Extra hepatic shunt index, however, was not significantly different in the two groups but was related more to the severity of the disease process. Spleno hepatic and spleno cardiac transit times were significantly lower cirrhotics as compared to the IPH group. We conclude that SSP is a technically simple, rapid and a much less invasive method of visualizing the portal circulatory system and assessing the portal haemo dynamics. it also provides clinically important measure of shunted blood nd allows for the quantification of circulatory time from spleen to liver and heart. (author)

  6. [Emphysematous gastritis with concomitant portal venous air].

    Science.gov (United States)

    Jeong, Min Yeong; Kim, Jin Il; Kim, Jae Young; Kim, Hyun Ho; Jo, Ik Hyun; Seo, Jae Hyun; Kim, Il Kyu; Cheung, Dae Young

    2015-02-01

    Emphysematous gastritis is a rare form of gastritis caused by infection of the stomach wall by gas forming bacteria. It is a very rare condition that carries a high mortality rate. Portal venous gas shadow represents elevation of intestinal luminal pressure which manifests as emphysematous gastritis or gastric emphysema. Literature reviews show that the mortality rate is especially high when portal venous gas shadow is present on CT scan. Until recently, the treatment of emphysematous gastritis has been immediate surgical intervention. However, there is a recent trend of avoiding surgery because of the frequent occurrence of post-operative complications such as anastomosis leakage. In addition, aggressive surgical treatment has failed to show significant improvement in prognosis. Recently, the authors experienced a case of emphysematous gastritis accompanied by portal venous gas which was treated successfully by conservative treatment without immediate surgical intervention. Herein, we present a case of emphysematous gastritis with concomitant portal venous air along with literature review.

  7. [Association of biliary calculosis and portal cavernomatosis].

    Science.gov (United States)

    Crespi, C; De Giorgio, A M

    1992-08-01

    This paper reports the case of a woman, who underwent surgery because of cholelithiasis, with intraoperative finding of prehepatic portal hypertension from portal vein thrombosis ("portal cavernoma") with healthy liver, later confirmed by angiographic studies. This rare pathologic association carries a higher risk of major operative complications; therefore the Authors agree with the general belief that, for these cases, biliary tract surgery should be as simple and safe as possible. In the case of preoperative diagnosis of biliary disease associated with portal cavernoma, should a surgical approach on the biliary tract be required, we agree on the advisability of performing a shunting procedure before any kind of biliary surgery. In case of variceal bleeding endoscopic sclerotherapy will be the first choice; surgical procedures (shunting) should be seen as a second choice in case of rebleeding after sclerotherapy.

  8. The International Human Epigenome Consortium Data Portal.

    Science.gov (United States)

    Bujold, David; Morais, David Anderson de Lima; Gauthier, Carol; Côté, Catherine; Caron, Maxime; Kwan, Tony; Chen, Kuang Chung; Laperle, Jonathan; Markovits, Alexei Nordell; Pastinen, Tomi; Caron, Bryan; Veilleux, Alain; Jacques, Pierre-Étienne; Bourque, Guillaume

    2016-11-23

    The International Human Epigenome Consortium (IHEC) coordinates the production of reference epigenome maps through the characterization of the regulome, methylome, and transcriptome from a wide range of tissues and cell types. To define conventions ensuring the compatibility of datasets and establish an infrastructure enabling data integration, analysis, and sharing, we developed the IHEC Data Portal (http://epigenomesportal.ca/ihec). The portal provides access to >7,000 reference epigenomic datasets, generated from >600 tissues, which have been contributed by seven international consortia: ENCODE, NIH Roadmap, CEEHRC, Blueprint, DEEP, AMED-CREST, and KNIH. The portal enhances the utility of these reference maps by facilitating the discovery, visualization, analysis, download, and sharing of epigenomics data. The IHEC Data Portal is the official source to navigate through IHEC datasets and represents a strategy for unifying the distributed data produced by international research consortia. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

  9. R2 Water Quality Portal Monitoring Stations

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Water Quality Data Portal (WQP) provides an easy way to access data stored in various large water quality databases. The WQP provides various input parameters on...

  10. Evaluation of portal hypertension by MR portography

    International Nuclear Information System (INIS)

    Nagaoka, Shirou; Hagiwara, Masaru; Imanisi, Yosimasa

    1997-01-01

    Seventy-eight examinations of MR portography were totally performed in 24 controls and 33 patients with esophageal varices. Portal vein, SMV, hepatic vein, and IVC were entirely depicted in 21, 24, 22, and 24, respectively, of the 24 controls. As to intrahepatic upward branches of portal vein in the right lobe of the liver, the 4th branch was at least depicted in all of the 24. Although the portal vein trunk and SMV were entirely depicted in all of the 8 patients without treatment and liver dysfunction of Child A, there was no depiction of them in 1 of the 8 patients with liver dysfunction of Child B, and 1 of 5 patients with liver dysfunction of Child C. The 4th upward branch of portal vein in the right lobe of the liver was depicted in none of the 33 patients. Besides, none of the intrahepatic portal branches were depicted in 1 of 8 patients without treatment and liver dysfunction of Child B, and 1 of the 5 patients without treatment and liver dysfunction of Child C. There was a significant difference of depicted terminal upward branch of portal vein between the controls and patients without any treatment. In the patients without any significant difference of depicted terminal upward branch of portal vein was also present between Child's classification A and Child's classification B and C. Gastric coronary vein varices were detected by MR portography is 18 of 19 patients without treatment on the esophageal varices, and paraesophageal/esophageal varices were also depicted by MR portography in 13 of the 19. The collaterals were depicted by MR portography in all of the 6 patients with recurrent collaterals after Hassab's operation or splenectomy. MR portography was able to depict flow in trunk branches and collaterals of the portal vein system in a physiological state. (K.H.)

  11. Getting started with Citrix CloudPortal

    CERN Document Server

    U, Puthiyavan

    2013-01-01

    The book will follow a step-by-step, tutorial-based approach and show readers how to take advantage of Citrix CloudPortal's capabilities.This book is ideal for administrators and engineers new to the Citrix Cloud Solution CPSM, CPBM, and who are looking to get a good grounding in Citrix's new product. It's assumed that you will have some experience in the basics of cloud computing already. No prior knowledge of CloudPortal is expected.

  12. Evaluation of portal hypertension by MR portography

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, Shirou; Hagiwara, Masaru; Imanisi, Yosimasa [St. Marianna Univ., Kawasaki, Kanagawa (Japan). School of Medicine

    1997-02-01

    Seventy-eight examinations of MR portography were totally performed in 24 controls and 33 patients with esophageal varices. Portal vein, SMV, hepatic vein, and IVC were entirely depicted in 21, 24, 22, and 24, respectively, of the 24 controls. As to intrahepatic upward branches of portal vein in the right lobe of the liver, the 4th branch was at least depicted in all of the 24. Although the portal vein trunk and SMV were entirely depicted in all of the 8 patients without treatment and liver dysfunction of Child A, there was no depiction of them in 1 of the 8 patients with liver dysfunction of Child B, and 1 of 5 patients with liver dysfunction of Child C. The 4th upward branch of portal vein in the right lobe of the liver was depicted in none of the 33 patients. Besides, none of the intrahepatic portal branches were depicted in 1 of 8 patients without treatment and liver dysfunction of Child B, and 1 of the 5 patients without treatment and liver dysfunction of Child C. There was a significant difference of depicted terminal upward branch of portal vein between the controls and patients without any treatment. In the patients without any significant difference of depicted terminal upward branch of portal vein was also present between Child`s classification A and Child`s classification B and C. Gastric coronary vein varices were detected by MR portography is 18 of 19 patients without treatment on the esophageal varices, and paraesophageal/esophageal varices were also depicted by MR portography in 13 of the 19. The collaterals were depicted by MR portography in all of the 6 patients with recurrent collaterals after Hassab`s operation or splenectomy. MR portography was able to depict flow in trunk branches and collaterals of the portal vein system in a physiological state. (K.H.)

  13. Portal de empleo JobFinder.com

    OpenAIRE

    Cozar Campoy, Javier

    2012-01-01

    Con este proyecto se pretende crear un portal web para la búsqueda de empleo. Las empresas inscritas en el sistema pueden publicar diferentes ofertas de trabajo y del mismo modo los usuarios registrados pueden inscribirse en éstas. Amb aquest projecte es pretén crear un portal web per a la cerca de feina. Les empreses inscrites en el sistema poden publicar diferents ofertes de feina i de la mateixa manera els usuaris registrats poden inscriure's en aquestes.

  14. Idiopathic Noncirrhotic Portal Hypertension: An Appraisal

    Science.gov (United States)

    Lee, Hwajeong; Rehman, Aseeb Ur; Fiel, M. Isabel

    2016-01-01

    Idiopathic noncirrhotic portal hypertension is a poorly defined clinical condition of unknown etiology. Patients present with signs and symptoms of portal hypertension without evidence of cirrhosis. The disease course appears to be indolent and benign with an overall better outcome than cirrhosis, as long as the complications of portal hypertension are properly managed. This condition has been recognized in different parts of the world in diverse ethnic groups with variable risk factors, resulting in numerous terminologies and lack of standardized diagnostic criteria. Therefore, although the diagnosis of idiopathic noncirrhotic portal hypertension requires clinical exclusion of other conditions that can cause portal hypertension and histopathologic confirmation, this entity is under-recognized clinically as well as pathologically. Recent studies have demonstrated that variable histopathologic entities with different terms likely represent a histologic spectrum of a single entity of which obliterative portal venopathy might be an underlying pathogenesis. This perception calls for standardization of the nomenclature and formulation of widely accepted diagnostic criteria, which will facilitate easier recognition of this disorder and will highlight awareness of this entity. PMID:26563701

  15. Management of Portal Hypertension After Liver Transplantation.

    Science.gov (United States)

    Korda, D; Deák, P Á; Kiss, G; Gerlei, Z; Kóbori, L; Görög, D; Fehérvári, I; Piros, L; Máthé, Z; Doros, A

    2017-09-01

    Post-transplantation portal hypertension has severe complications, such as esophageal varix bleeding, therapy refractory ascites, extreme splenomegaly, and graft dysfunction. The aim of our study was to analyze the effectiveness of the therapeutic strategies and how to visualize the procedure. A retrospective study involving liver transplantation patients from the Semmelweis University Department of Transplantation and Surgery was performed between 2005 and 2015. The prevalence, etiology, and leading complications of the condition were determined. The applied interventions' effects on the patients' ascites volume, splenic volume, and the occurrence of variceal bleeding were determined. Mean portal blood flow velocity and congestion index values were calculated using Doppler ultrasonography. The prevalence of post-transplantation portal hypertension requiring intervention was 2.8%. The most common etiology of the disease was portal anastomotic stenosis. The most common complications were esophageal varix bleeding and therapy refractory ascites. The patients' ascites volume decreased significantly (2923.3 ± 1893.2 mL vs. 423.3 ± 634.3 mL; P portal hypertension. After the interventions, these parameters shifted towards the physiologic ranges. The interventions performed in our clinic were effective in most cases. The patients' ascites volume, splenic volume, and the prevalence of variceal bleeding decreased after the treatment. Doppler ultrasonography has proved to be a valuable imaging modality in the diagnosis and the follow-up of post-transplantation portal hypertension. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Biological Petri Nets

    CERN Document Server

    Wingender, E

    2011-01-01

    It was suggested some years ago that Petri nets might be well suited to modeling metabolic networks, overcoming some of the limitations encountered by the use of systems employing ODEs (ordinary differential equations). Much work has been done since then which confirms this and demonstrates the usefulness of this concept for systems biology. Petri net technology is not only intuitively understood by scientists trained in the life sciences, it also has a robust mathematical foundation and provides the required degree of flexibility. As a result it appears to be a very promising approach to mode

  17. Reconfiguration of distribution nets

    International Nuclear Information System (INIS)

    Latorre Bayona, Gerardo; Angarita Marquez, Jorge Luis

    2000-01-01

    Starting of the location of the reconfiguration problem inside the context of the operation of distribution nets, of the quality indicators definition and of the presentation of the alternatives more used for reduction of technical losses, they are related diverse reconfiguration methodologies proposed in the technical literature, pointing out their three principals limitations; also are presents the results of lost obtained starting from simulation works carried out in distribution circuits of the ESSA ESP, which permitting to postulate the reconfiguration of nets like an excellent alternative to reduce technical losses

  18. NET system integration

    International Nuclear Information System (INIS)

    Farfaletti-Casali, F.; Mitchell, N.; Salpietro, E.; Buzzi, U.; Gritzmann, P.

    1985-01-01

    The NET system integration procedure is the process by which the requirements of the various Tokamak machine design areas are brought together to form a compatible machine layout. Each design area produces requirements which generally allow components to be built at minimum cost and operate with minimum technical risk, and the final machine assembly should be achieved with minimum departure from these optimum designs. This is carried out in NET by allowing flexibility in the maintenance and access methods to the machine internal components which must be regularly replaced by remote handling, in segmentation of these internal components and in the number of toroidal field coils

  19. Search Engine For Ebook Portal

    Directory of Open Access Journals (Sweden)

    Prashant Kanade

    2017-05-01

    Full Text Available The purpose of this paper is to establish the textual analytics involved in developing a search engine for an ebook portal. We have extracted our dataset from Project Gutenberg using a robot harvester. Textual Analytics is used for efficient search retrieval. The entire dataset is represented using Vector Space Model where each document is a vector in the vector space. Further for computational purposes we represent our dataset in the form of a Term Frequency- Inverse Document Frequency tf-idf matrix. The first step involves obtaining the most coherent sequence of words of the search query entered. The entered query is processed using Front End algorithms this includes-Spell Checker Text Segmentation and Language Modeling. Back End processing includes Similarity Modeling Clustering Indexing and Retrieval. The relationship between documents and words is established using cosine similarity measured between the documents and words in Vector Space. Clustering performed is used to suggest books that are similar to the search query entered by the user. Lastly the Lucene Based Elasticsearch engine is used for indexing on the documents. This allows faster retrieval of data. Elasticsearch returns a dictionary and creates a tf-idf matrix. The processed query is compared with the dictionary obtained and tf-idf matrix is used to calculate the score for each match to give most relevant result.

  20. Mapping carbon flux uncertainty and selecting optimal locations for future flux towers in the Great Plains

    Science.gov (United States)

    Gu, Yingxin; Howard, Daniel M.; Wylie, Bruce K.; Zhang, Li

    2012-01-01

    Flux tower networks (e. g., AmeriFlux, Agriflux) provide continuous observations of ecosystem exchanges of carbon (e. g., net ecosystem exchange), water vapor (e. g., evapotranspiration), and energy between terrestrial ecosystems and the atmosphere. The long-term time series of flux tower data are essential for studying and understanding terrestrial carbon cycles, ecosystem services, and climate changes. Currently, there are 13 flux towers located within the Great Plains (GP). The towers are sparsely distributed and do not adequately represent the varieties of vegetation cover types, climate conditions, and geophysical and biophysical conditions in the GP. This study assessed how well the available flux towers represent the environmental conditions or "ecological envelopes" across the GP and identified optimal locations for future flux towers in the GP. Regression-based remote sensing and weather-driven net ecosystem production (NEP) models derived from different extrapolation ranges (10 and 50%) were used to identify areas where ecological conditions were poorly represented by the flux tower sites and years previously used for mapping grassland fluxes. The optimal lands suitable for future flux towers within the GP were mapped. Results from this study provide information to optimize the usefulness of future flux towers in the GP and serve as a proxy for the uncertainty of the NEP map.

  1. Determination of Surface Fluxes Using a Bowen Ratio System

    African Journals Online (AJOL)

    USER

    Components of the surface fluxes of the energy balance equation were determined ... and vapour pressure in combination with point measurements of net .... approaches zero, then almost all the energy available is used in evapotranspiration.

  2. Coloured Petri Nets

    CERN Document Server

    Jensen, Kurt

    2009-01-01

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. This book introduces the constructs of the CPN modelling language and presents the related analysis methods. It provides a comprehensive road map for the practical use of CPN.

  3. Safety nets or straitjackets?

    DEFF Research Database (Denmark)

    Ilsøe, Anna

    2012-01-01

    Does regulation of working hours at national and sector level impose straitjackets, or offer safety nets to employees seeking working time flexibility? This article compares legislation and collective agreements in the metal industries of Denmark, Germany and the USA. The industry has historically...

  4. Neuronal nets in robotics

    International Nuclear Information System (INIS)

    Jimenez Sanchez, Raul

    1999-01-01

    The paper gives a generic idea of the solutions that the neuronal nets contribute to the robotics. The advantages and the inconveniences are exposed that have regarding the conventional techniques. It also describe the more excellent applications as the pursuit of trajectories, the positioning based on images, the force control or of the mobile robots management, among others

  5. Net4Care platform

    DEFF Research Database (Denmark)

    2012-01-01

    , that in turn enables general practitioners and clinical staff to view observations. Use the menus above to explore the site's information resources. To get started, follow the short Hello, World! tutorial. The Net4Care project is funded by The Central Denmark Region and EU via Caretech Innovation....

  6. Coloured Petri Nets

    DEFF Research Database (Denmark)

    Jensen, Kurt; Kristensen, Lars Michael

    Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. The development of such systems is particularly challenging because of inherent intricacies like possible nondeterminism an...

  7. Game Theory .net.

    Science.gov (United States)

    Shor, Mikhael

    2003-01-01

    States making game theory relevant and accessible to students is challenging. Describes the primary goal of GameTheory.net is to provide interactive teaching tools. Indicates the site strives to unite educators from economics, political and computer science, and ecology by providing a repository of lecture notes and tests for courses using…

  8. BacillusRegNet

    DEFF Research Database (Denmark)

    Misirli, Goksel; Hallinan, Jennifer; Röttger, Richard

    2014-01-01

    As high-throughput technologies become cheaper and easier to use, raw sequence data and corresponding annotations for many organisms are becoming available. However, sequence data alone is not sufficient to explain the biological behaviour of organisms, which arises largely from complex molecular...... the associated BacillusRegNet website (http://bacillus.ncl.ac.uk)....

  9. Boom Booom Net Radio

    DEFF Research Database (Denmark)

    Grimshaw, Mark Nicholas; Yong, Louisa; Dobie, Ian

    1999-01-01

    of an existing Internet radio station; Boom Booom Net Radio. Whilst necessity dictates some use of technology-related terminology, wherever possible we have endeavoured to keep such jargon to a minimum and to either explain it in the text or to provide further explanation in the appended glossary....

  10. MR and angiography: Evaluation of the hemodynamics of portal hypertension

    International Nuclear Information System (INIS)

    Torres, W.E.; Gaylord, G.M.; Whitmire, L.; Chuang, V.P.; Bernardino, M.E.

    1986-01-01

    Forty-two MR imaging examinations and angiographic procedures in 38 patients with portal hypertension were compared for how well the images depicted portal perfusion and direction of flow, portal vein thrombosis, and the presence and type of shunt. Thirty-three MR imaging studies indicated grade I or II portal flow. In 29 cases portal flow was grade I or II by angiography; in the remaining cases the flow was grade IV. In a total of eight cases portal flow was grade IV by angiography, but none appeared to be grade IV on MR imaging. Both MR imaging and angiography detected portal vein thrombosis (41 of 42 cases). MR imaging and angiography agreed as to whether a shunt was present or absent, and patent or occluded (41 of 42 cases). Currently, MR imaging is an unsatisfactory modality by which to grade portal flow. MR imaging does depict portal vein thrombosis well, and can be used to determine patency of surgical shunts

  11. Applications of portals in the energetic sector; Aplicaciones de portales en el sector energetico

    Energy Technology Data Exchange (ETDEWEB)

    Santos Dominguez, Martin; Arroyo Figueroa, Gustavo [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2000-07-01

    An operative portal joins the applications, contents and services of the company in a single page of Intranet such way that promises to change deeply the information technology in the next years. The corporative portals will change what people visualize in the screen of their computer at the beginning of every working day. Unlike seeing the network (Web) only with pages of language of hypertext bearing (HTML), the corporative portal acts as a gate between Internet and the private networks. This article presents a general vision of the benefits of the corporative portals, the existing technologies and the potential markets. [Spanish] Un portal operativo une las aplicaciones, contenidos y servicios de la empresa en una sola pagina de Intranet, de tal forma que promete cambiar, profundamente la tecnologia de la informacion en los proximos anos. Los portales corporativos cambiaran lo que la gente visualiza en la pantalla de su computadora al comienzo de cada dia de trabajo. A diferencia de ver la red (Web) solo con paginas de lenguaje de marcacion de hipertexto (HTML), el portal corporativo actua como compuerta entre Internet y las redes privadas. Este articulo presenta una vision general de los beneficios de los portales corporativos, las tecnologias y los mercados potenciales existentes.

  12. An Approach for harmonizing European Water Portals

    Science.gov (United States)

    Pesquer, Lluís; Stasch, Christoph; Masó, Joan; Jirka, Simon; Domingo, Xavier; Guitart, Francesc; Turner, Thomas; Hinderk Jürrens, Eike

    2017-04-01

    A number of European funded research projects is developing novel solutions for water monitoring, modeling and management. To generate innovations in the water sector, third parties from industry and the public sector need to take up the solutions and bring them into the market. A variety of portals exists to support this move into the market. Examples on the European level are the EIP Water Online Marketplace(1), the WaterInnEU Marketplace(2), the WISE RTD Water knowledge portal(3), the WIDEST- ICT for Water Observatory(4) or the SWITCH-ON Virtual Product Market and Virtual Water-Science Laboratory(5). Further innovation portals and initiatives exist on the national or regional level, for example, the Denmark knows water platform6 or the Dutch water alliance(7). However, the different portals often cover the same projects, the same products and the same services. Since they are technically separated and have their own data models and databases, people need to duplicate information and maintain it at several endpoints. This requires additional efforts and hinders the interoperable exchange between these portals and tools using the underlying data. In this work, we provide an overview on the existing portals and present an approach for harmonizing and integrating common information that is provided across different portals. The approach aims to integrate the common in formation in a common database utilizing existing vocabularies, where possible. An Application Programming Interface allows access the information in a machine-readable way and utilizing the information in other applications beyond description and discovery purposes. (1) http://www.eip-water.eu/my-market-place (2) https://marketplace.waterinneu.org (3) http://www.wise-rtd.info/ (4) http://iwo.widest.eu (5) http://www.switch-on-vwsl.eu/ (6) http://www.rethinkwater.dk/ (7) http://wateralliance.nl/

  13. Next Gen One Portal Usability Evaluation

    Science.gov (United States)

    Cross, E. V., III; Perera, J. S.; Hanson, A. M.; English, K.; Vu, L.; Amonette, W.

    2018-01-01

    Each exercise device on the International Space Station (ISS) has a unique, customized software system interface with unique layouts / hierarchy, and operational principles that require significant crew training. Furthermore, the software programs are not adaptable and provide no real-time feedback or motivation to enhance the exercise experience and/or prevent injuries. Additionally, the graphical user interfaces (GUI) of these systems present information through multiple layers resulting in difficulty navigating to the desired screens and functions. These limitations of current exercise device GUI's lead to increased crew time spent on initiating, loading, performing exercises, logging data and exiting the system. To address these limitations a Next Generation One Portal (NextGen One Portal) Crew Countermeasure System (CMS) was developed, which utilizes the latest industry guidelines in GUI designs to provide an intuitive ease of use approach (i.e., 80% of the functionality gained within 5-10 minutes of initial use without/limited formal training required). This is accomplished by providing a consistent interface using common software to reduce crew training, increase efficiency & user satisfaction while also reducing development & maintenance costs. Results from the usability evaluations showed the NextGen One Portal UI having greater efficiency, learnability, memorability, usability and overall user experience than the current Advanced Resistive Exercise Device (ARED) UI used by astronauts on ISS. Specifically, the design of the One-Portal UI as an app interface similar to those found on the Apple and Google's App Store, assisted many of the participants in grasping the concepts of the interface with minimum training. Although the NextGen One-Portal UI was shown to be an overall better interface, observations by the test facilitators noted specific exercise tasks appeared to have a significant impact on the NextGen One-Portal UI efficiency. Future updates to

  14. The Sydney West Knowledge Portal: Evaluating the Growth of a Knowledge Portal to Support Translational Research.

    Science.gov (United States)

    Janssen, Anna; Robinson, Tracy Elizabeth; Provan, Pamela; Shaw, Tim

    2016-06-29

    The Sydney West Translational Cancer Research Centre is an organization funded to build capacity for translational research in cancer. Translational research is essential for ensuring the integration of best available evidence into practice and for improving patient outcomes. However, there is a low level of awareness regarding what it is and how to conduct it optimally. One solution to addressing this gap is the design and deployment of web-based knowledge portals to disseminate new knowledge and engage with and connect dispersed networks of researchers. A knowledge portal is an web-based platform for increasing knowledge dissemination and management in a specialized area. To measure the design and growth of an web-based knowledge portal for increasing individual awareness of translational research and to build organizational capacity for the delivery of translational research projects in cancer. An adaptive methodology was used to capture the design and growth of an web-based knowledge portal in cancer. This involved stakeholder consultations to inform initial design of the portal. Once the portal was live, site analytics were reviewed to evaluate member usage of the portal and to measure growth in membership. Knowledge portal membership grew consistently for the first 18 months after deployment, before leveling out. Analysis of site metrics revealed members were most likely to visit portal pages with community-generated content, particularly pages with a focus on translational research. This was closely followed by pages that disseminated educational material about translational research. Preliminary data from this study suggest that knowledge portals may be beneficial tools for translating new evidence and fostering an environment of communication and collaboration.

  15. The MISTRALS programme data portal

    Science.gov (United States)

    Fleury, Laurence; Brissebrat, Guillaume; Belmahfoud, Nizar; Boichard, Jean-Luc; Brosolo, Laetitia; Cloché, Sophie; Descloitres, Jacques; Ferré, Hélène; Focsa, Loredana; Labatut, Laurent; Mastrorillo, Laurence; Mière, Arnaud; Petit de la Villéon, Loïc; Ramage, Karim; Schmechtig, Catherine

    2014-05-01

    different file formats and data processing tools. The MISTRALS data portal - http://mistrals.sedoo.fr/ - has been designed and developed as a unified tool to share scientific data in spite of many sources of heterogeneity, and to foster collaboration between research communities. The metadata (data description) are standardized and comply with international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). A search tool allows to browse the catalogue by keyword or by multicriteria selection (location, period, physical property...) and to access data. Data sets managed by different data centres (ICARE, IPSL, SEDOO, CORIOLIS) are available through interoperability protocols (OPeNDAP, xml requests...) or archive synchronisation. At present the MISTRALS data portal allows to access more than 400 datasets and counts more than 500 registered users. The number of available datasets is increasing daily, due to the provision of campaign datasets (2012, 2013) by several projects. Every in situ data set is available in the native format, but the favorite data sets have been homogenized (property names, units, quality flags...) and inserted in a relational database, in order to enable more accurate data selection, and download of different datasets in a shared format. Every scientist is invited to make use of the different MISTRALS tools and data. Do not hesitate to browse the catalogue and fill the online registration form. Feel free to contact mistrals-contact@sedoo.fr for any question.

  16. The MISTRALS programme data portal

    Science.gov (United States)

    Brissebrat, Guillaume; Belmahfoud, Nizar; Cloché, Sophie; Darras, Sabine; Descloitres, Jacques; Drocourt, Yoann; Ferré, Hélène; Henriot, Nicolas; Ramage, Karim

    2017-04-01

    different file formats and data processing tools. The MISTRALS data portal - http://mistrals.sedoo.fr/ - has been designed and developed as a unified tool for sharing scientific data in spite of many sources of heterogeneity, and for fostering collaboration between research communities. The metadata (data description) are standardized and comply with international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). A search tool allows to browse the catalog by keyword or multicriteria selection (area, period, physical property...) and to access data. Every in situ dataset is available in the native format, but the most commonly used datasets have been homogenized (property names, units, quality flags...) and inserted in a relational database, in order to enable accurate data selection, and download in standard formats. At present the MISTRALS data portal enables to access about 650 datasets. It counts more than 675 registered users and about 100 data requests every month. The number of available datasets is increasing daily, due to the provision of campaign datasets by several projects. Every scientist is invited to browse the catalog, complete the online registration and use MISTRALS data. Feel free to contact mistrals-contact@sedoo.fr for any question.

  17. Calcification in the portal venous system demonstrated by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hadar, H; Sommer, R

    1983-08-01

    The CT appearance of calcification in the portal venous system in a patient with chronic alcoholic cirrhosis is presented. Reported cases of radiologically detectable calcification in the portal system are rare, and most of them have been associated with longstanding portal hypertension. We presume that with CT this diagnosis will be made more frequently. In the presence of calcification in the portal venous system, portal vein thrombosis is highly probable. This information is of obvious importance to the surgeon contemplating a portal decompressive shunt procedure.

  18. Unexpected disappearance of portal cavernoma on long-term anticoagulation.

    Science.gov (United States)

    Silva-Junior, Gilberto; Turon, Fanny; Hernandez-Gea, Virginia; Darnell, Anna; García-Criado, Ángeles; García-Pagán, Juan Carlos

    2014-08-01

    Idiopathic non-cirrhotic portal hypertension is a rare disease of unknown etiology. Patients with idiopathic non-cirrhotic portal hypertension have an increased risk of developing portal vein thrombosis and this is especially prevalent when HIV is also present. We describe a unique case of a patient with idiopathic non-cirrhotic portal hypertension associated to HIV, who developed acute portal vein thrombosis that despite anticoagulation transformed in portal cavernoma and disappeared completely after five years of follow-up on continuous anticoagulation. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  19. Thermal Performance Testing of Cryogenic Multilayer Insulation with Silk Net Spacers

    International Nuclear Information System (INIS)

    Johnson, W L; Frank, D J; Nast, T C; Fesmire, J E

    2015-01-01

    Early comprehensive testing of cryogenic multilayer insulation focused on the use of silk netting as a spacer material. Silk netting was used for multiple test campaigns that were designed to provide baseline thermal performance estimates for cryogenic insulation systems. As more focus was put on larger systems, the cost of silk netting became a deterrent and most aerospace insulation firms were using Dacron (or polyester) netting spacers by the early 1970s. In the midst of the switch away from silk netting there was no attempt to understand the difference between silk and polyester netting, though it was widely believed that the silk netting provided slightly better performance. Without any better reference for thermal performance data, the silk netting performance correlations continued to be used. In order to attempt to quantify the difference between the silk netting and polyester netting, a brief test program was developed. The silk netting material was obtained from Lockheed Martin and was tested on the Cryostat-100 instrument in three different configurations, 20 layers with both single and double netting and 10 layers with single netting only. The data show agreement within 15 - 30% with the historical silk netting based correlations and show a substantial performance improvement when compared to previous testing performed using polyester netting and aluminum foil/fiberglass paper multilayer insulation. Additionally, the data further reinforce a recently observed trend that the heat flux is not directly proportional to the number of layers installed on a system. (paper)

  20. Regional blood flows by the microsphere method: reproducibility in portal hypertensive rats and influence of a portal vein catheter

    International Nuclear Information System (INIS)

    Hadengue, A.; Lee, S.S.; Koshy, A.; Girod, C.; Lebrec, D.

    1988-01-01

    To determine the reproducibility of splanchnic blood flow measurements by the microsphere method in rats with portal hypertension and the effects of laparotomy with portal vein cannulation, eight groups of 10 rats were studied. Microspheres were labelled with 113 Sn or 141 Ce. Laparotomy with portal cannulation had no significant effect in sham-operated rats. In awake portal hypertensive rats, cardiac output and splanchnic blood flow were lower in portal vein cannulated rats compared with those of non-cannulated animals. In anesthetized portal hypertensive rats blood flows were unaffected by portal cannulation, but arterial pressure and heart rate were elevated. Anesthesia also decreased portal pressure in portal hypertensive rats. We conclude that the microsphere method remains reproducible in portal hypertensive rat models. Laparotomy with portal cannulation can alter systemic and splanchnic hemodynamics in portal hypertensive rats; these effects can also be changed during pentobarbital anesthesia. Regional blood flow measurements in portal hypertensive rats should be performed in animals without portal cannulation and preferably in the awake state

  1. Metabolic effects of portal vein sensing.

    Science.gov (United States)

    Mithieux, G

    2014-09-01

    The extrinsic gastrointestinal nerves are crucial in the sensing of nutrients and hormones and its translation in terms of control of food intake. Major macronutrients like glucose and protein are sensed by the extrinsic nerves located in the portal vein walls, which signal to the brain and account for the satiety phenomenon they promote. Glucose is sensed in the portal vein by neurons expressing the glucose receptor SGLT3, which activate the main regions of the brain involved in the control of food intake. Proteins indirectly act on food intake by inducing intestinal gluconeogenesis and its sensing by the portal glucose sensor. The mechanism involves a prior antagonism by peptides of the μ-opioid receptors present in the portal vein nervous system and a reflex arc with the brain inducing intestinal gluconeogenesis. In a comparable manner, short-chain fatty acids produced from soluble fibre act via intestinal gluconeogenesis to exert anti-obesity and anti-diabetic effects. In the case of propionate, the mechanism involves a prior activation of the free fatty acid receptor FFAR3 present in the portal nerves and a reflex arc initiating intestinal gluconeogenesis. © 2014 John Wiley & Sons Ltd.

  2. SolNet

    DEFF Research Database (Denmark)

    Jordan, Ulrike; Vajen, Klaus; Bales, Chris

    2014-01-01

    -accompanying Master courses, placements of internships, and PhD scholarship projects. A new scholarship project, “SHINE”, was launched in autumn 2013 in the frame work of the Marie Curie program of the European Union (Initial Training Network, ITN). 13 PhD-scholarships on solar district heating, solar heat......SolNet, founded in 2006, is the first coordinated International PhD education program on Solar Thermal Engineering. The SolNet network is coordinated by the Institute of Thermal Engineering at Kassel University, Germany. The network offers PhD courses on solar heating and cooling, conference...... for industrial processes, as well as sorption stores and materials started in December 2013. Additionally, the project comprises a training program with five PhD courses and several workshops on solar thermal engineering that will be open also for other PhD students working in the field. The research projects...

  3. Percutaneous transhepatic portal vein stenting in a patient with benign non-transplant postoperative portal vein stenosis: A case report

    Directory of Open Access Journals (Sweden)

    KS Madhusudhan

    2013-01-01

    Full Text Available Extrahepatic portal vein stenosis is caused by a variety of benign and malignant diseases and results in development of symptoms due to portal hypertension. Benign post-surgical adhesions causing portal vein stenosis in non-transplant population is an uncommon etiology of portal hypertension. Endovascular treatment of such patients with angioplasty and stenting is uncommonly reported in literature. We report a case of portal hypertension caused by benign postoperative portal vein fibrosis, successfully treated by self-expandable metallic stent.

  4. Turkey's net energy consumption

    International Nuclear Information System (INIS)

    Soezen, Adnan; Arcaklioglu, Erol; Oezkaymak, Mehmet

    2005-01-01

    The main goal of this study is to develop the equations for forecasting net energy consumption (NEC) using an artificial neural-network (ANN) technique in order to determine the future level of energy consumption in Turkey. In this study, two different models were used in order to train the neural network. In one of them, population, gross generation, installed capacity and years are used in the input layer of the network (Model 1). Other energy sources are used in input layer of network (Model 2). The net energy consumption is in the output layer for two models. Data from 1975 to 2003 are used for the training. Three years (1981, 1994 and 2003) are used only as test data to confirm this method. The statistical coefficients of multiple determinations (R 2 -value) for training data are equal to 0.99944 and 0.99913 for Models 1 and 2, respectively. Similarly, R 2 values for testing data are equal to 0.997386 and 0.999558 for Models 1 and 2, respectively. According to the results, the net energy consumption using the ANN technique has been predicted with acceptable accuracy. Apart from reducing the whole time required, with the ANN approach, it is possible to find solutions that make energy applications more viable and thus more attractive to potential users. It is also expected that this study will be helpful in developing highly applicable energy policies

  5. Knowledge Management Portal: A Simplified Model to Help Decision Makers

    International Nuclear Information System (INIS)

    Ogawa, I.; Hernandes Tabares, R.

    2015-01-01

    The aim of this work is to present a simplified model that could help the nuclear industry to keep the expertise of safeguards professionals in touch with the state of the art, and also to have available information in the Portal of Knowledge Management. It can also provide indicators and general data for decision makers. Authors have developed the concept based on their own experience through systems running in hydroelectric and gas fired plants, and one exclusive system that manage all courses in one University. It is under development a Portal of Knowledge Management for NPP dealing with information obtained of Strategic Plans, Budgets and Economics, Operation Performance, Maintenance and Surveillance Plans, Training and Education Programs, QA Programs, Operational Experience, Safety Culture, and Engineering of Human Factors. This model will provide indicators for decision makers. Training and education module is prepared according to profile of each individual and his attributes, tasks and capabilities, and training and education programmes. The system could apply self-assessment questionnaires; immersive learning using media (video) classes, and test applications using questions randomly selected from data bank, as well as could make applications to certificate people. All these data are analyzed and generate indicators about strongest and weakness points. Managers could have indication of individual's deficiency even though in training programmes on a real time basis. Another tool that could be applied to the model is the remote operation of supervision equipment. The model is developed using web-based tools, like ASP.NET encrypted by 128 bits, and web site https. Finally, it is important to stress that the model can be customized according to industry preference. (author)

  6. Best Practices for Building Web Data Portals

    Science.gov (United States)

    Anderson, R. A.; Drew, L.

    2013-12-01

    With a data archive of more than 1.5 petabytes and a key role as the NASA Distributed Active Archive Center (DAAC) for synthetic aperture radar (SAR) data, the Alaska Satellite Facility (ASF) has an imperative to develop effective Web data portals. As part of continuous enhancement and expansion of its website, ASF recently created two data portals for distribution of SAR data: one for the archiving and distribution of NASA's MEaSUREs Wetlands project and one for newly digitally processed data from NASA's 1978 Seasat satellite. These case studies informed ASF's development of the following set of best practices for developing Web data portals. 1) Maintain well-organized, quality data. This is fundamental. If data are poorly organized or contain errors, credibility is lost and the data will not be used. 2) Match data to likely data uses. 3) Identify audiences in as much detail as possible. ASF DAAC's Seasat and Wetlands portals target three groups of users: a) scientists already familiar with ASF DAAC's SAR archive and our data download tool, Vertex; b) scientists not familiar with SAR or ASF, but who can use the data for their research of oceans, sea ice, volcanoes, land deformation and other Earth sciences; c) audiences wishing to learn more about SAR and its use in Earth sciences. 4) Identify the heaviest data uses and the terms scientists search for online when trying to find data for those uses. 5) Create search engine optimized (SEO) Web content that corresponds to those searches. Because search engines do not yet search raw data, so Web data portals must include content that ties the data to its likely uses. 6) Create Web designs that best serves data users (user centered design), not for how the organization views itself or its data. Usability testing was conducted for the ASF DAAC Wetlands portal to improve the user experience. 7) Use SEO tips and techniques. The ASF DAAC Seasat portal used numerous SEO techniques, including social media, blogging

  7. Radionuclide assessment of portal hypertension syndrome

    International Nuclear Information System (INIS)

    Aliev, M.A.; Khusain, Sh.K.; Alpeisova, Sh.T.

    2005-01-01

    This paper presents review of radionuclide studies for portal hypertension patients. Presented results showed that portal hypertension signs were revealed for the first group patients. The signs become apparent by splenomegaly and increase of colloid accumulation in it. Accumulation of the chemical in spleen was evidence of ingestion rate increase of reticuloendothelial system owing to its hyperplasia as well as liver phagocytic activity decrease due to pathological paren-chematous process and inter liver blockade. The most typical scintigraphic signs of portal hypertension were determined according chemical accumulation decreased in spleen and marrow sequentially. It is determined radionuclide method contributes to assessment of structural and functional aberrations character in liver and spleen for cirrhosis patients. (author)

  8. ERNIE performance with TSA portals Initial Results

    Energy Technology Data Exchange (ETDEWEB)

    Labov, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2018-01-05

    This project extends the “Enhanced Radiological Nuclear Inspection and Evaluation” (ERNIE) system developed with CBP and DNDO to improve performance of PVT-based Radiation Portal Monitors (RPMs). ERNIE was designed to be used with any RPM system. The first implementation was with the SAIC (Leidos) RPM-8 systems. In this project, we are demonstrating how effective the ERNIE approach can be when applied to the VM250 TSA portals used in NSDD programs. Part of the challenge in adapting ERNIE to handle VM250 portals is the lack of gamma spectral information. We report here on the first results showing how the ERNIE analysis can improve analysis of measurements with the VM250 RPMs.

  9. Perivesical varices and portal hypertension: imaging study

    International Nuclear Information System (INIS)

    Mallorquin Jimenez, F.; Medina Benitez, A.; Lopez Machado, E.; Pardo Moreno, M.D.; Garrido Moreno, C.; Pastor Rull, J.

    1995-01-01

    Nine patients with portal hypertension syndrome and Perivesical varices are studied retrospectively by means of imaging techniques including ultrasound, duplex Doppler, color Doppler, CT and angiography. All the patients presented portal thrombosis and thickening of the bladder wall. These collaterals either represent a shunting of hepato pedal flow or correspond to blood stasis associated with said syndrome. Ultrasound, whether involving duplex Doppler or color Doppler techniques, is highly useful to detect the presence of Perivesical varices which appear as tubular or rounded hypo echogenic areas in the bladder wall. Given the association of this entity with bladder wall thickening, it should be taken into account in any clinical situation involving said change, especially in patients with portal hypertension; moreover knowledge of its presence is of great importance when the possibility of creating shunts by means of interventional or surgical vascular procedures or other types of abdominal procedures are being considered because of the risk of bleeding. (Author)

  10. Configuring Mobile Commerce Portals for Business Success

    DEFF Research Database (Denmark)

    Dholakia, Nikhilesh; Rask, Morten

    2004-01-01

    -portals must attract and retain customers. Success in mobile portal markets will depend on dynamic strategies that blend elements of personalization, permission, and specification of content. This chapter reviews the key differences between traditional e-commerce and the emergent m-commerce. It reviews...... the core concepts of personalization, permission, and content specification as they apply to e-commerce and m-commerce. The chapter presents a framework for developing effective business strategies for developing and managing mobile portals. http://www.morten-rask.dk/2003c.htm......M-commerce entails transactions conducted via mobile telecommunications networks using communication, information, and payment devices such as mobile phones or palmtop units. Geographic positioning and location capabilities are also being added to such networks and devices. Rather than using...

  11. Portal monitor evaluation and test procedure

    International Nuclear Information System (INIS)

    Johnson, L.O.; Gupta, V.P.; Stevenson, R.L.; Rich, B.L.

    1983-10-01

    The purpose was to develop techniques and procedures to allow users to measure performance and sensitivity of portal monitors. Additionally, a methodology was developed to assist users in optimizing monitor performance. The two monitors tested utilized thin-window gas-flow proportional counters sensitive to beta and gamma radiation. Various tests were performed: a) background count rate and the statistical variability, b) detector efficiency at different distances, c) moving source sensitivity for various size sources and speeds, and d) false alarm rates at different background levels. A model was developed for the moving source measurements to compare the experimental data with measured results, and to test whether it is possible to adequately model the behavior of a portal monitor's response to a moving source. The model results were compared with the actual test results. A procedure for testing portal monitors is also given. 1 reference, 9 figures, 8 tables

  12. Building a Smart Portal for Astronomy

    Science.gov (United States)

    Derriere, S.; Boch, T.

    2011-07-01

    The development of a portal for accessing astronomical resources is not an easy task. The ever-increasing complexity of the data products can result in very complex user interfaces, requiring a lot of effort and learning from the user in order to perform searches. This is often a design choice, where the user must explicitly set many constraints, while the portal search logic remains simple. We investigated a different approach, where the query interface is kept as simple as possible (ideally, a simple text field, like for Google search), and the search logic is made much more complex to interpret the query in a relevant manner. We will present the implications of this approach in terms of interpretation and categorization of the query parameters (related to astronomical vocabularies), translation (mapping) of these concepts into the portal components metadata, identification of query schemes and use cases matching the input parameters, and delivery of query results to the user.

  13. Alongshore wind stress and heat flux divergence off Visakhapatnam, east coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Sadhuram, Y.; Rao, B.P.; Rao, D.P.

    Annual variation of heat flux divergence (Qv) was computed for the coastal waters of Visakhapatnam. The mean values of net heat exchange (Qn) and heat flux divergence (Qv) were found to be 114 and 115 W.m/2 respectively on annual scale. The net heat...

  14. Critical flux determination by flux-stepping

    DEFF Research Database (Denmark)

    Beier, Søren; Jonsson, Gunnar Eigil

    2010-01-01

    In membrane filtration related scientific literature, often step-by-step determined critical fluxes are reported. Using a dynamic microfiltration device, it is shown that critical fluxes determined from two different flux-stepping methods are dependent upon operational parameters such as step...... length, step height, and.flux start level. Filtrating 8 kg/m(3) yeast cell suspensions by a vibrating 0.45 x 10(-6) m pore size microfiltration hollow fiber module, critical fluxes from 5.6 x 10(-6) to 1.2 x 10(-5) m/s have been measured using various step lengths from 300 to 1200 seconds. Thus......, such values are more or less useless in itself as critical flux predictors, and constant flux verification experiments have to be conducted to check if the determined critical fluxes call predict sustainable flux regimes. However, it is shown that using the step-by-step predicted critical fluxes as start...

  15. Application of the smart portal in transportation

    International Nuclear Information System (INIS)

    Kercel, S.W.; Baylor, V.M.; Dress, W.B.; Hickerson, T.W.; Jatko, W.B.; Labaj, L.E.; Muhs, J.D.; Pack, R.M.

    1996-01-01

    Under a program sponsored by the Department of Energy, the Oak Ridge complex is developed a ''Portal-of-the-Future'', or ''smart portal''. This is a security portal for vehicular traffic which is intended to quickly detect explosives, hidden passengers, etc. It uses several technologies, including microwaves, weigh-in-motion, digital image processing, and electroacoustic wavelet-based heartbeat detection. A novel component of particular interest is the Enclosed Space Detection System (ESDS), which detects the presence of persons hiding in a vehicle. The system operates by detecting the presence of a human ballistocardiographic signature. Each time the heart beats, it generates a small but measurable shock wave that propagates through the body. The wave, whose graph is called a ballistocardiogram, is the mechanical analog of the electrocardiogram, which is routinely used for medical diagnosis. The wave is, in turn, coupled to any surface or object with which the body is in contact. If the body is located in an enclosed space, this will result in a measurable deflection of the surface of the enclosure. Independent testing has shown ESDS to be highly reliable. The technologies used in the smart portal operate in real time and allow vehicles to be checked through the portal in much less time than would be required for human inspection. Although not originally developed for commercial transportation, the smart portal has the potential to solve several transportation problems. It could relieve congestion at international highway border crossings by reducing the time required to inspect each vehicle while increasing the level of security. It can reduce highway congestion at the entrance of secure facilities such as prisons. Also, it could provide security at intermodal transfer points, such as airport parking lots and car ferry terminals

  16. Application of the smart portal in transportation

    Energy Technology Data Exchange (ETDEWEB)

    Kercel, S.W.; Baylor, V.M.; Dress, W.B.; Hickerson, T.W.; Jatko, W.B.; Labaj, L.E.; Muhs, J.D.; Pack, R.M.

    1996-12-31

    Under a program sponsored by the Department of Energy, the Oak Ridge complex is developed a ``Portal-of-the-Future``, or ``smart portal``. This is a security portal for vehicular traffic which is intended to quickly detect explosives, hidden passengers, etc. It uses several technologies, including microwaves, weigh-in-motion, digital image processing, and electroacoustic wavelet-based heartbeat detection. A novel component of particular interest is the Enclosed Space Detection System (ESDS), which detects the presence of persons hiding in a vehicle. The system operates by detecting the presence of a human ballistocardiographic signature. Each time the heart beats, it generates a small but measurable shock wave that propagates through the body. The wave, whose graph is called a ballistocardiogram, is the mechanical analog of the electrocardiogram, which is routinely used for medical diagnosis. The wave is, in turn, coupled to any surface or object with which the body is in contact. If the body is located in an enclosed space, this will result in a measurable deflection of the surface of the enclosure. Independent testing has shown ESDS to be highly reliable. The technologies used in the smart portal operate in real time and allow vehicles to be checked through the portal in much less time than would be required for human inspection. Although not originally developed for commercial transportation, the smart portal has the potential to solve several transportation problems. It could relieve congestion at international highway border crossings by reducing the time required to inspect each vehicle while increasing the level of security. It can reduce highway congestion at the entrance of secure facilities such as prisons. Also, it could provide security at intermodal transfer points, such as airport parking lots and car ferry terminals.

  17. Interactive monitoring portal for fusion simulations

    International Nuclear Information System (INIS)

    Abla, G.; Schissel, D.P.; Kim, E.N.; Flanagan, S.M.; Lee, X.

    2012-01-01

    Highlights: ► We designed a web-based monitoring system that tracks the status of fusion simulations. ► Our system is scalable to monitor the simulations running on distributed supercomputers and clusters located at multiple geographical locations. ► The monitoring portal provides a web-based interface for post-run analysis, such as visualizing the results, logging the user comments, and rating the simulation quality. ► Our system utilizes the open source software, such as Python, Django, MySQL, Apache, and MDSplus. - Abstract: The Center for Simulation of RF Wave Interactions with Magnetohydrodynamics (SWIM) Project is a proto-Fusion Simulation Program (FSP) whose goal is to study high-performance fusion plasmas and perform comprehensive simulations that are essential to the development of fusion. SWIM team members are geographically distributed and utilize distributed supercomputers for computational simulations. Due to the highly distributed computational work environment, the SWIM team has the difficulty of monitoring code runs and discovering historical runs. To alleviate this difficulty a web-based monitoring portal has been developed and deployed. The monitoring portal tracks the progress of simulations and automatically collects metadata in real-time. This capability helps scientists to effectively utilize precious computer resources. Furthermore, the portal provides a web-based interface for post-run analysis, such as visualizing the results, logging the user comments, and rating the simulation quality. The user interface provides rapid discovery capability via multi-field searching and sorting. The development of the monitoring portal used open source software, such as Python, Django, MySQL, and Apache. It uses MDSplus for data management, Memcached for data caches, and OpenID for single sign-on security. This paper describes the software architecture, related technologies and deployment experiences of the monitoring portal.

  18. Application of the smart portal in transportation

    Science.gov (United States)

    Kercel, Stephen W.; Baylor, Vivian M.; Dress, William B.; Hickerson, Tim W.; Jatko, William B.; Labaj, Leo E.; Muhs, Jeffrey D.; Pack, Richard M.

    1997-02-01

    Under a program sponsored by the Department of Energy, the Oak Ridge complex is developing a `Portal-of-the-Future', or `smart portal.' This is a security portal for vehicular traffic which is intended to quickly detect explosives, hidden passengers, etc. It uses several technologies, including microwaves, weigh-in-motion, digital image processing, and electroacoustic wavelet-based heartbeat detection. A novel component of particular interest is the Enclosed Space Detection System (ESDS), which detects the presence of persons hiding in a vehicle. The system operates by detecting the presence of a human ballistocardiographic signature. Each time the heart beats, it generates a small but measurable shock wave that propagates through the body. The wave, whose graph is called a ballistocardiogram, is the mechanical analog of the electrocardiograms, which is routinely used for medical diagnosis. The wave is, in turn, coupled to any surface or object with which the body is in contact. If the body is located in an enclosed space, this will result in a measurable deflection of the surface of the enclosure. Independent testing has shown ESDS to be highly reliable. The technologies used in the smart portal operate in real time and allow vehicles to be checked through the portal in much less time than would be required for human inspection. Although not originally developed for commercial transportation, the smart portal has the potential to solve several transportation problems. It could relieve congestion at international highway border crossings by reducing the time required to inspect each vehicle while increasing the level of security. It can reduce highway congestion at the entrance of secure facilities such as prisons. Also, it could provide security at intermodal transfer points, such as airport parking lots and car ferry terminals.

  19. Portal placement in elbow arthroscopy by novice surgeons: cadaver study.

    Science.gov (United States)

    Claessen, Femke M A P; Kachooei, Amir R; Kolovich, Gregory P; Buijze, Geert A; Oh, Luke S; van den Bekerom, Michel P J; Doornberg, Job N

    2017-07-01

    In this anatomical cadaver study, the distance between major nerves and ligaments at risk for injury and portal sites created by trainees was measured. Trainees, inexperienced in elbow arthroscopy, have received a didactic lecture and cadaver instruction prior to portal placement. The incidence of iatrogenic injury from novice portal placement was also determined. Anterolateral, direct lateral, and anteromedial arthroscopic portals were created in ten cadavers by ten inexperienced trainees in elbow arthroscopy. After creating each portal, the trajectory of the portal was marked with a guide pin. Subsequently, the cadavers were dissected and the distances between the guide pin in the anterolateral, direct lateral, and anteromedial portals and important ligaments and nerves were measured. The difference between the distance of the direct lateral portal and the posterior antebrachial cutaneous nerve (PABCN) (22 mm, p cadaver instruction session alone. Level of evidence V.

  20. R2 Water Quality Portal Monitoring Stations

    Science.gov (United States)

    The Water Quality Data Portal (WQP) provides an easy way to access data stored in various large water quality databases. The WQP provides various input parameters on the form including location, site, sampling, and date parameters to filter and customize the returned results. The The Water Quality Portal (WQP) is a cooperative service sponsored by the United States Geological Survey (USGS), the Environmental Protection Agency (EPA) and the National Water Quality Monitoring Council (NWQMC) that integrates publicly available water quality data from the USGS National Water Information System (NWIS) the EPA STOrage and RETrieval (STORET) Data Warehouse, and the USDA ARS Sustaining The Earth??s Watersheds - Agricultural Research Database System (STEWARDS).

  1. Ship-borne contour integration for flux determination

    NARCIS (Netherlands)

    Groeskamp, S.; Maas, L.R.M.

    2012-01-01

    The consumption of nutrients by mussel beds can be monitored by measuring the net nutrient flux across a circumscribing vertical surface. Measuring this nutrient flux not only requires resolving the spatial (and temporal) distribution of nutrients at the bounding contour, but also an ability to

  2. Net one, net two: the primary care network income statement.

    Science.gov (United States)

    Halley, M D; Little, A W

    1999-10-01

    Although hospital-owned primary care practices have been unprofitable for most hospitals, some hospitals are achieving competitive advantage and sustainable practice operations. A key to the success of some has been a net income reporting tool that separates practice operating expenses from the costs of creating and operating a network of practices to help healthcare organization managers, physicians, and staff to identify opportunities to improve the network's financial performance. This "Net One, Net Two" reporting allows operations leadership to be held accountable for Net One expenses and strategic leadership to be held accountable for Net Two expenses.

  3. Duplication of the Portal Vein: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Won; Shin, Hyeong Cheol; Jou, Sung Shick; Han, Jong Kyu; Kim, Il Young [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of)

    2009-12-15

    The duplication of the portal vein is an uncommon congenital anomaly. To date, only four cases have been reported in the medical literature. This anomaly can cause portal hypertension in pediatric patients. In addition, duplication of the portal vein has various patterns of connection with a splenic vein or mesenteric veins, and it can lie anterior or posterior to the duodenum. We report the MDCT findings of an adult patient with duplication of the portal vein that was found incidentally

  4. Proof Nets for Lambek Calculus

    NARCIS (Netherlands)

    Roorda, Dirk

    1992-01-01

    The proof nets of linear logic are adapted to the non-commutative Lambek calculus. A different criterion for soundness of proof nets is given, which gives rise to new algorithms for proof search. The order sensitiveness of the Lambek calculus is reflected by the planarity condition on proof nets;

  5. Net metering: zero electricity bill

    International Nuclear Information System (INIS)

    Mangi, A.; Khan, Z.

    2011-01-01

    Worldwide move towards renewable energy sources, environmental concerns and decentralization of the power sector have made net metering an attractive option for power generation at small scale. This paper discusses the net metering, economical issues of renewable sources in Pakistan, technical aspects, installation suitability according to varying terrain, existing utility rules and formulation of legislation for net metering making it economically attractive. (author)

  6. The Net Advance of Physics

    Science.gov (United States)

    THE NET ADVANCE OF PHYSICS Review Articles and Tutorials in an Encyclopædic Format Established 1995 [Link to MIT] Computer support for The Net Advance of Physics is furnished by The Massachusetts Newest Additions SPECIAL FEATURES: Net Advance RETRO: Nineteenth Century Physics History of Science

  7. Horizontal ichthyoplankton tow-net system with unobstructed net opening

    Science.gov (United States)

    Nester, Robert T.

    1987-01-01

    The larval fish sampler described here consists of a modified bridle, frame, and net system with an obstruction-free net opening and is small enough for use on boats 10 m or less in length. The tow net features a square net frame attached to a 0.5-m-diameter cylinder-on-cone plankton net with a bridle designed to eliminate all obstructions forward of the net opening, significantly reducing currents and vibrations in the water directly preceding the net. This system was effective in collecting larvae representing more than 25 species of fish at sampling depths ranging from surface to 10 m and could easily be used at greater depths.

  8. Assessment of the quality of educational portals

    Directory of Open Access Journals (Sweden)

    R. G. Bolbakov

    2017-01-01

    Full Text Available The article describes the results of theoretical and experimental studies on the evaluation of the quality of educational information placed on information and educational portals. The methodology allows you to compare not only portals, but also the results of training on exam scores and test scores. The methodological basis of the assessment is the cognitive approach and the negentropic approach. The article gives a comparison of entropy and negentropy. On the basis of comparison, the authors propose a negentropic approach to assessing the quality of educational resources obtained as a result of information retrieval. The search results are evaluated by cognitive and perpetual scores. Estimates are introduced into the entropy formula and converted to the formula of negentropy. The negentropic approach serves as the basis for calculating the statistical amount of information obtained as a result of information retrieval. The cognitive approach serves as a basis for assessing the qualitative characteristics of educational information, such as: visibility, perceptibility, interpretability. Open information portalsare the source of educational resources. The article shows that modern information portals are often clogged with unreliable or unnecessary information, which makes it difficult to find relevant educational information. In contrast to the widespread methods for one relevanceassess of the information retrieval, this article differentiates the notion of the relevance of the information retrieval. The article introduces three qualitatively different notions of relevance: formal, semantic and perpetual – relevance. The article introduces new additional characteristics of the quality of information search, the coefficient of cognition and the coefficient of perpetuation. These coefficients are introduced into the formula for estimating entropy and obtain the cognitive-entropy formula. As a result, a new method for assessing the content of

  9. Portal Hypertension Secondary to Spontaneous Arterio-Portal Venous Fistulas: Transcatheter Arterial Embolization with n-Butyl Cyanoacrylate and Microcoils

    International Nuclear Information System (INIS)

    Yamagami, Takuji; Nakamura, Toshiyuki; Nishimura, Tsunehiko

    2000-01-01

    We report a 73-year-old man with recurrent variceal bleeding due to portal hypertension caused by multiple intrahepatic arterio-portal venous fistulas, which were successfully occluded by embolization with n-butyl cyanoacrylate and micro-coils

  10. Base of tongue varices associated with portal hypertension

    OpenAIRE

    Jassar, P; Jaramillo, M; Nunez, D

    2000-01-01

    A symptomatic case of tongue base varices in a patient with portal hypertension secondary to liver cirrhosis is presented. There are no previously documented cases in the world literature. Oesophageal varices may not be the only source of expectorated blood in a patient with portal hypertension.


Keywords: portal hypertension; lingual; tongue; varicose vein

  11. User Needs of Digital Service Web Portals: A Case Study

    Science.gov (United States)

    Heo, Misook; Song, Jung-Sook; Seol, Moon-Won

    2013-01-01

    The authors examined the needs of digital information service web portal users. More specifically, the needs of Korean cultural portal users were examined as a case study. The conceptual framework of a web-based portal is that it is a complex, web-based service application with characteristics of information systems and service agents. In…

  12. Velocity Estimation of the Main Portal Vein with Transverse Oscillation

    DEFF Research Database (Denmark)

    Brandt, Andreas Hjelm; Hansen, Kristoffer Lindskov; Nielsen, Michael Bachmann

    2015-01-01

    This study evaluates if Transverse Oscillation (TO) can provide reliable and accurate peak velocity estimates of blood flow the main portal vein. TO was evaluated against the recommended and most widely used technique for portal flow estimation, Spectral Doppler Ultrasound (SDU). The main portal...

  13. Master Robotic Net

    Directory of Open Access Journals (Sweden)

    Vladimir Lipunov

    2010-01-01

    Full Text Available The main goal of the MASTER-Net project is to produce a unique fast sky survey with all sky observed over a single night down to a limiting magnitude of 19-20. Such a survey will make it possible to address a number of fundamental problems: search for dark energy via the discovery and photometry of supernovae (including SNIa, search for exoplanets, microlensing effects, discovery of minor bodies in the Solar System, and space-junk monitoring. All MASTER telescopes can be guided by alerts, and we plan to observe prompt optical emission from gamma-ray bursts synchronously in several filters and in several polarization planes.

  14. FluxVisualizer, a Software to Visualize Fluxes through Metabolic Networks

    Directory of Open Access Journals (Sweden)

    Tim Daniel Rose

    2018-04-01

    Full Text Available FluxVisualizer (Version 1.0, 2017, freely available at https://fluxvisualizer.ibgc.cnrs.fr is a software to visualize fluxes values on a scalable vector graphic (SVG representation of a metabolic network by colouring or increasing the width of reaction arrows of the SVG file. FluxVisualizer does not aim to draw metabolic networks but to use a customer’s SVG file allowing him to exploit his representation standards with a minimum of constraints. FluxVisualizer is especially suitable for small to medium size metabolic networks, where a visual representation of the fluxes makes sense. The flux distribution can either be an elementary flux mode (EFM, a flux balance analysis (FBA result or any other flux distribution. It allows the automatic visualization of a series of pathways of the same network as is needed for a set of EFMs. The software is coded in python3 and provides a graphical user interface (GUI and an application programming interface (API. All functionalities of the program can be used from the API and the GUI and allows advanced users to add their own functionalities. The software is able to work with various formats of flux distributions (Metatool, CellNetAnalyzer, COPASI and FAME export files as well as with Excel files. This simple software can save a lot of time when evaluating fluxes simulations on a metabolic network.

  15. Four-collector flux sensor

    International Nuclear Information System (INIS)

    Wiegand, W.J. Jr.; Bullis, R.H.; Mongeon, R.J.

    1980-01-01

    A flowmeter based on ion drift techniques was developed for measuring the rate of flow of a fluid through a given cross-section. Ion collectors are positioned on each side of an immediately adjacent to ion source. When air flows axially through the region in which ions are produced and appropriate electric fields are maintained between the collectors, an electric current flows to each collector due to the net motion of the ions. The electric currents and voltages and other parameters which define the flow are combined in an electric circuit so that the flux of the fluid can be determined. (DN)

  16. Novel Rat Model of Repetitive Portal Venous Embolization Mimicking Human Non-Cirrhotic Idiopathic Portal Hypertension

    DEFF Research Database (Denmark)

    Klein, Sabine; Hinüber, Christian; Hittatiya, Kanishka

    2016-01-01

    BACKGROUND: Non-cirrhotic idiopathic portal hypertension (NCIPH) is characterized by splenomegaly, anemia and portal hypertension, while liver function is preserved. However, no animal models have been established yet. This study assessed a rat model of NCIPH and characterized the hemodynamics......, and compared it to human NCIPH. METHODS: Portal pressure (PP) was measured invasively and coloured microspheres were injected in the ileocecal vein in rats. This procedure was performed weekly for 3 weeks (weekly embolization). Rats without and with single embolization served as controls. After four weeks (one...... in the weekly embolization group. Fibrotic markers αSMA and Desmin were upregulated in weekly embolized rats. DISCUSSION: This study establishes a model using repetitive embolization via portal veins, comparable with human NCIPH and may serve to test new therapies....

  17. Limitations of shallow nets approximation.

    Science.gov (United States)

    Lin, Shao-Bo

    2017-10-01

    In this paper, we aim at analyzing the approximation abilities of shallow networks in reproducing kernel Hilbert spaces (RKHSs). We prove that there is a probability measure such that the achievable lower bound for approximating by shallow nets can be realized for all functions in balls of reproducing kernel Hilbert space with high probability, which is different with the classical minimax approximation error estimates. This result together with the existing approximation results for deep nets shows the limitations for shallow nets and provides a theoretical explanation on why deep nets perform better than shallow nets. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Estimating daytime ecosystem respiration from eddy-flux data

    DEFF Research Database (Denmark)

    Bruhn, Dan; Mikkelsen, Teis Nørgaard; Herbst, Mathias

    2011-01-01

    To understand what governs the patterns of net ecosystem exchange of CO2, an understanding of factors influencing the component fluxes, ecosystem respiration and gross primary production is needed. In the present paper, we introduce an alternative method for estimating daytime ecosystem respiration...... based on whole ecosystem fluxes from a linear regression of photosynthetic photon flux density data vs. daytime net ecosystem exchange data at forest ecosystem level. This method is based on the principles of the Kok-method applied at leaf level for estimating daytime respiration. We demonstrate...

  19. GENIUS: a web portal for the grid

    International Nuclear Information System (INIS)

    Andronico, A.; Barbera, R.; Falzone, A.; Lo Re, G.; Pulvirenti, A.; Rodolico, A.

    2003-01-01

    The architecture and the current implementation of the grid portal GENIUS (Grid Enabled web environment for site Independent User job Submission), jointly developed by INFN and NICE within the context of the INFN Grid and DataGrid Project, is presented and discussed

  20. Diagnosis of portal hypertension with radioactive isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Lewitus, Z

    1974-01-01

    Administration of /sup 131/I in a microclysma and simultaneous recording of the radioactivity in the liver and precordium allows the diagnosis of portal hypertension in at least 90 percent of the cases. This test has been used now for more than 5 years in patients with liver diseases. The simplicity of the test makes it a valuable bedside procedure.

  1. Extrahepatic complications to cirrhosis and portal hypertension

    DEFF Research Database (Denmark)

    Møller, Søren; Henriksen, Jens H; Bendtsen, Flemming

    2014-01-01

    In addition to complications relating to the liver, patients with cirrhosis and portal hypertension develop extrahepatic functional disturbances of multiple organ systems. This can be considered a multiple organ failure that involves the heart, lungs, kidneys, the immune systems, and other organ...

  2. Liver surgery in cirrhosis and portal hypertension.

    Science.gov (United States)

    Hackl, Christina; Schlitt, Hans J; Renner, Philipp; Lang, Sven A

    2016-03-07

    The prevalence of hepatic cirrhosis in Europe and the United States, currently 250 patients per 100000 inhabitants, is steadily increasing. Thus, we observe a significant increase in patients with cirrhosis and portal hypertension needing liver resections for primary or metastatic lesions. However, extended liver resections in patients with underlying hepatic cirrhosis and portal hypertension still represent a medical challenge in regard to perioperative morbidity, surgical management and postoperative outcome. The Barcelona Clinic Liver Cancer classification recommends to restrict curative liver resections for hepatocellular carcinoma in cirrhotic patients to early tumor stages in patients with Child A cirrhosis not showing portal hypertension. However, during the last two decades, relevant improvements in preoperative diagnostic, perioperative hepatologic and intensive care management as well as in surgical techniques during hepatic resections have rendered even extended liver resections in higher-degree cirrhotic patients with portal hypertension possible. However, there are few standard indications for hepatic resections in cirrhotic patients and risk stratifications have to be performed in an interdisciplinary setting for each individual patient. We here review the indications, the preoperative risk-stratifications, the morbidity and the mortality of extended resections for primary and metastatic lesions in cirrhotic livers. Furthermore, we provide a review of literature on perioperative management in cirrhotic patients needing extrahepatic abdominal surgery and an overview of surgical options in the treatment of hepatic cirrhosis.

  3. [Evaluation and treatment of portal hypertension].

    Science.gov (United States)

    Brůha, Radan; Petrtýl, Jaromír

    Liver cirrhosis is a serious disease shortening the life expectancy. Unavoidable consequence of cirrhosis is portal hypertension, which usually limits the prognosis by its complications. Portal hypertension is a prognostic factor for cirrhosis decompensation, variceal bleeding and even the mortality in cirrhotic patients. In the evaluation of portal hypertension hepatic venous pressure gradient (HVPG) measurement is used.Measurement of HVPG is used in clinical praxis in these situations: diagnosis of portal hypertension, evaluation of prognosis of patients with cirrhosis, monitoring the treatment efficacy in the prevention of variceal bleeding, management of acute variceal bleeding. Decrease of HVPG below 12 mmHg or at least for more than 20% of initial value in the treatment by beta-blockers is associated with the lower risk of bleeding from varices or other complications. HVPG above 20 mm Hg is associated with the high risk of early rebleeding from varices and can discriminate those patients profiting from early TIPS.HVPG measurement is an invasive, but simple, reproducible and safe catheterization technique with minimal complication rate. The most frequent complication could be incorrect assessment of obtained values. HVPG measurement should be a routine technique in centers specialized to liver diseases.

  4. Measuring Problem Solving Skills in "Portal 2"

    Science.gov (United States)

    Shute, Valerie J.; Wang, Lubin

    2013-01-01

    This paper examines possible improvement to problem solving skills as a function of playing the video game "Portal 2." Stealth assessment is used in the game to evaluate students' problem solving abilities--specifically basic and flexible rule application. The stealth assessment measures will be validated against commonly accepted…

  5. Portal hypertension due to choledochal cyst

    International Nuclear Information System (INIS)

    Athar, M.; Haider, M.H.R.; Khan, M.A.; Khaliq, T.; Ahmad, N.

    2002-01-01

    A case of portal hypertension secondary to choledochal cyst is reported. A young female presented with haematemesis, malena and splenomegaly in addition to the classic triad of jaundice, pain and abdominal mass. Oesophagogastroscopy revealed second degree varices. Excision of cyst and hepaticojejunostomy was performed. At six months follow up patient was completely asymptomatic with no endoscopic evidence of varices. (author)

  6. An Empirical Investigation of Campus Portal Usage

    Science.gov (United States)

    Saghapour, Mohsen; Iranmanesh, Mohammad; Zailani, Suhaiza; Goh, Gerald Guan Gan

    2018-01-01

    This study has determined the determinants of the perceived ease of use and perceived usefulness and their influence on campus portal usage. A quantitative approach was employed, using a five-point Likert scale questionnaire, adapted from previous studies. Data were gathered through a survey conducted with 341 staff working in the University of…

  7. Physics Experiments at the UNEDLabs Portal

    Directory of Open Access Journals (Sweden)

    Juan pedro Sánchez

    2012-01-01

    Full Text Available UNEDLabs is a web portal based on a free, modern, open source, and well-known learning management system: Moodle. This portal joins two theme networks of virtual and remote laboratories (one for Control Engineering and another one for Physics, named AutomatL@bs and FisL@bs, respectively together. AutomatL@bs has been operative for five years now. Following AutomatL@bs’ scheme, FisL@bs was created as a network of remote and virtual laboratories for physics university education via the Internet to offer students the possibility of performing hands-on experiences in different fields of physics in two ways: simulation and real remote operation. Now, both FisL@bs and AutomatL@bs join together (while maintaining their independency into an unique new web portal called UNEDLabs. This work focuses on this new web environment and gives a detailed account of a novel way in Physics to let distance learning students gain practical experience autonomously. This paper explains how the new portal works and the software tools used for creating it. In addition, it also describes the physics experiments which are already operative.

  8. ICPP digital wide area portal monitor

    International Nuclear Information System (INIS)

    Nichols, C.E.

    1978-01-01

    A portal montior is described which is used to check personnel for contamination. The monitor is extremely sensitive. In addition to personnel contamination control, it serves as an extremely effective SNM detector capable of detecting U-235 in half the quantities specified in Federal Standards

  9. A neutron portal monitor for vehicles

    International Nuclear Information System (INIS)

    Coop, K.L.; Fehlau, P.E.; Atwater, H.F.

    1987-01-01

    We have designed and built a portal vehicle monitoring systems for detecting neutron-emitting special nuclear material (SNM) such as plutonium. Monte Carlo calculations were used to optimize the design of the 15-cm-deep x 122-cm-high x 244-cm-long detector chambers, which utilize 3 He proportional counters inside a hollow polyethylene box. Results for a variety of parametric studies, including polyethylene thickness and detector number, are described. Our experimental measurements are in good agreement with the computer calculations. The monitor's decision logic uses the Sequential Probability Ratio Test (SPRT) on Poisson distributed counting data, which is superior to other statistical tests in many applications. We performed computer simulations of the SPRT logic to determine expected false-positive decision rates. A controller unit of our design that uses this SPRT was built commercially. The cost of the complete monitoring system is similar to that of vehicle portal monitors that detect gamma rays. This new neutron monitor can serve as an addition to standard gamma-ray vehicle portals or as a stand-alone portal monitor in particular safeguards monitoring situations. The monitor is being tested at Los Alamos and is scheduled for in-plant evaluation of another DOE facility in 1987. 7 refs

  10. Left-sided portal hypertension revisited

    Directory of Open Access Journals (Sweden)

    Antonio Manenti

    2016-12-01

    Conclusions: In every case of left-sided portal hypertension, upper digestive endoscopy and close follow-up are recommended. Besides, computed tomography can demonstrate particular conditions directly favoring gastroesophageal varices, and aid in selection of the appropriate therapeutic decisions. [Arch Clin Exp Surg 2016; 5(4.000: 211-215

  11. Portal hypertension in schistosomiasis: pathophysiology and treatment

    Directory of Open Access Journals (Sweden)

    Luiz Caetano da Silva

    1992-01-01

    Full Text Available In heavily infected young patients, there is a "non-congestive" phase of the disease with splenomegaly which can improve after chemoterapy. A strong correlation between hepatosplenic form and worm burden in young patients has been repeatedly shown. The pattern of vascular intrhepatic lesions seems to depend on two mechanisms: (a egg embolization, with a partial blocking of the portal vasculature; (b the appearance of small portal collaterals along the intrahepatic portal sistem. The role played by hepatitis B virus (HBV and C virus infections in the pathogenesis of liver lesions is variably considered. Selective arteriography shows a reduced diameter of hepatic artery with thin and arched branches outlining vascular gaps. A rich arterial network , as described in autopsy cases, is usually not seen in vivo, except after splenectomy or shunt surgery. An augmented hepatic arterial flow was demonstrated in infected animals. These facts suggest that the poor intrahepatic arterial vascularization demonstrated by selective arteriography in humans is due to a "functional deviation"of arterial blood to the splenic territory. The best results obtained in treatment of portal hypertension were: esophagogastric desvascularization and splenectomy (EGDS, although risk of rebleeding persists; classical (proximal splenorenal shunt (SRS should be abandoned; distal splenorenal shunt may complicate with hepatic encephalopaty, although later and in a lower percentage than in SRS. Propranolol is currently under investigation. In our Department, schistosomotic patients with esophageal varices bleeding are treated by EGDS and, if rebleeding occurs, by sclerosis of the varices.

  12. Portal Environment in Today’s Business

    OpenAIRE

    Aldubaikhi, Ammar

    2015-01-01

    Companies can get benefits from new business models as they can have better and efficient collaboration system and this can be derived from the discussed application in this paper. Companies that easily personalize the SAP enterprise portal are more productive and this reflects their interests in business

  13. Shielding calculations for NET

    International Nuclear Information System (INIS)

    Verschuur, K.A.; Hogenbirk, A.

    1991-05-01

    In the European Fusion Technology Programme there is only a small activity on research and development for fusion neutronics. Never-the-less, looking further than blanket design now, as ECN is getting involved in design of radiation shields for the coils and biological shields, it becomes apparent that fusion neutronics as a whole still needs substantial development. Existing exact codes for calculation of complex geometries like MCNP and DORT/TORT are put over the limits of their numerical capabilities, whilst approximate codes for complex geometries like FURNACE and MERCURE4 are put over the limits of their modelling capabilities. The main objective of this study is just to find out how far we can get with existing codes in obtaining reliable values for the radiation levels inside and outside the cryostat/shield during operation and after shut-down. Starting with a 1D torus model for preliminary parametric studies, more dimensional approximation of the torus or parts of it including the main heterogeneities should follow. Regular contacts with the NET-Team are kept, to be aware of main changes in NET design that might affect our calculation models. Work on the contract started 1 July 1990. The technical description of the contract is given. (author). 14 refs.; 4 figs.; 1 tab

  14. Morphological and biomechanical remodeling of the hepatic portal vein in a swine model of portal hypertension.

    Science.gov (United States)

    He, Xi-Ju; Huang, Tie-Zhu; Wang, Pei-Jun; Peng, Xing-Chun; Li, Wen-Chun; Wang, Jun; Tang, Jie; Feng, Na; Yu, Ming-Hua

    2012-02-01

    To obtain the morphological and biomechanical remodeling of portal veins in swine with portal hypertension (PHT), so as to provide some mechanical references and theoretical basis for clinical practice about PHT. Twenty white pigs were used in this study, 14 of them were subjected to both carbon tetrachloride- and pentobarbital-containing diet to induce experimental liver cirrhosis and PHT, and the remaining animals served as the normal controls. The morphological remodeling of portal veins was observed. Endothelial nitric oxide synthase expression profile in the vessel wall was assessed at both mRNA and protein level. The biomechanical changes of the hepatic portal veins were evaluated through assessing the following indicators: the incremental elastic modulus, pressure-strain elastic modulus, volume elastic modulus, and the incremental compliance. The swine PHT model was successfully established. The percentages for the microstructural components and the histological data significantly changed in the experimental group. Endothelial nitric oxide synthase expression was significantly downregulated in the portal veins of the experimental group. Three incremental elastic moduli (the incremental elastic modulus, pressure-strain elastic modulus, and volume elastic modulus) of the portal veins from PHT animals were significantly larger than those of the controls (P portal vein decreased. Our study suggests that the morphological and biomechanical properties of swine hepatic portal veins change significantly during the PHT process, which may play a critical role in the development of PHT and serve as potential therapeutic targets during clinical practice. Copyright © 2012 Annals of Vascular Surgery Inc. Published by Elsevier Inc. All rights reserved.

  15. Wall shear stress in portal vein of cirrhotic patients with portal hypertension.

    Science.gov (United States)

    Wei, Wei; Pu, Yan-Song; Wang, Xin-Kai; Jiang, An; Zhou, Rui; Li, Yu; Zhang, Qiu-Juan; Wei, Ya-Juan; Chen, Bin; Li, Zong-Fang

    2017-05-14

    To investigate wall shear stress (WSS) magnitude and distribution in cirrhotic patients with portal hypertension using computational fluid dynamics. Idealized portal vein (PV) system models were reconstructed with different angles of the PV-splenic vein (SV) and superior mesenteric vein (SMV)-SV. Patient-specific models were created according to enhanced computed tomography images. WSS was simulated by using a finite-element analyzer, regarding the blood as a Newtonian fluid and the vessel as a rigid wall. Analysis was carried out to compare the WSS in the portal hypertension group with that in healthy controls. For the idealized models, WSS in the portal hypertension group (0-10 dyn/cm 2 ) was significantly lower than that in the healthy controls (10-20 dyn/cm 2 ), and low WSS area (0-1 dyn/cm 2 ) only occurred in the left wall of the PV in the portal hypertension group. Different angles of PV-SV and SMV-SV had different effects on the magnitude and distribution of WSS, and low WSS area often occurred in smaller PV-SV angle and larger SMV-SV angle. In the patient-specific models, WSS in the cirrhotic patients with portal hypertension (10.13 ± 1.34 dyn/cm 2 ) was also significantly lower than that in the healthy controls ( P portal hypertension, the low WSS area extended to wider levels and the magnitude of WSS reached lower levels, thereby being more prone to disturbed flow occurrence. Cirrhotic patients with portal hypertension show dramatic hemodynamic changes with lower WSS and greater potential for disturbed flow, representing a possible causative factor of PV thrombosis.

  16. VitisNet: "Omics" integration through grapevine molecular networks.

    Directory of Open Access Journals (Sweden)

    Jérôme Grimplet

    Full Text Available BACKGROUND: Genomic data release for the grapevine has increased exponentially in the last five years. The Vitis vinifera genome has been sequenced and Vitis EST, transcriptomic, proteomic, and metabolomic tools and data sets continue to be developed. The next critical challenge is to provide biological meaning to this tremendous amount of data by annotating genes and integrating them within their biological context. We have developed and validated a system of Grapevine Molecular Networks (VitisNet. METHODOLOGY/PRINCIPAL FINDINGS: The sequences from the Vitis vinifera (cv. Pinot Noir PN40024 genome sequencing project and ESTs from the Vitis genus have been paired and the 39,424 resulting unique sequences have been manually annotated. Among these, 13,145 genes have been assigned to 219 networks. The pathway sets include 88 "Metabolic", 15 "Genetic Information Processing", 12 "Environmental Information Processing", 3 "Cellular Processes", 21 "Transport", and 80 "Transcription Factors". The quantitative data is loaded onto molecular networks, allowing the simultaneous visualization of changes in the transcriptome, proteome, and metabolome for a given experiment. CONCLUSIONS/SIGNIFICANCE: VitisNet uses manually annotated networks in SBML or XML format, enabling the integration of large datasets, streamlining biological functional processing, and improving the understanding of dynamic processes in systems biology experiments. VitisNet is grounded in the Vitis vinifera genome (currently at 8x coverage and can be readily updated with subsequent updates of the genome or biochemical discoveries. The molecular network files can be dynamically searched by pathway name or individual genes, proteins, or metabolites through the MetNet Pathway database and web-portal at http://metnet3.vrac.iastate.edu/. All VitisNet files including the manual annotation of the grape genome encompassing pathway names, individual genes, their genome identifier, and chromosome

  17. Palliative treatment of TIPS to portal vein tumor thrombosis complicated with portal vein hypertension

    International Nuclear Information System (INIS)

    Jiang Zaibo; Shan Hong; Guan Shouhai; Zhu Kangshun; Huang Mingsheng; Li Zhengran; Guo Tiansheng; Liu Lang

    2002-01-01

    Objective: To evaluate the palliative therapeutic effects of transjugular intrahepatic portosystemic shunt (TIPS) in portal vein tumor thrombosis (PVTT) complicated with portal vein hypertension, and to discuss the technical skills. Methods: There were 14 cases of end-stage hepatocellular carcinoma complicated with PVTT and portal vein hypertension, the average age was 53.6 yr. There were 8 cases with complete occlusion of main portal vein, 6 eases with incomplete thrombosis, and 5 cases combined with portal vein cavernous transformation. One case had simple hemorrhage, 3 eases had intractable ascites, and 10 cases had hemorrhage accompanied by intractable ascites. Results: The procedure of TIPS was successful in 10 cases, the successful rate was about 71%. The mean portal vein pressure was reduced from 37.2 mm Hg to 18.2 mm Hg, with an average reduction of 19.0 mm Hg. After the procedure of TIPS, the ascites decreased, hemorrhage stopped and the clinical symptoms disappeared. The average survival period was 132.3 days. The procedure were failing in 4 cases. Conclusion: TIPS was an effective palliative therapeutic methods to control the hemorrhage and ascites aroused by hepatic carcinoma complicated with PVTT

  18. The application of TIPSS in portal vein cancerous thrombosis complicated with portal hypertension

    International Nuclear Information System (INIS)

    Jiang Zaibo; Shan Hong; Guan Shouhai; Zhu Kangshun; Huang Mingsheng; Li Zhengran; Zhu Wenke; Liu Lang; Guo Tiansheng

    2002-01-01

    Objective: To discuss the technical skills and the contraindication of trans-jugular intrahepatic portosystemic shunt stent (TIPSS) in portal vein cancerous thrombosis (PVCT) complicated with portal hypertension. Methods: There were 16 cases of PVCT with portal hypertension, and average age of 53.6 yr. There were 9 cases with complete occlusion of portal vein trunk and 7 cases with incomplete thrombosis. There were 5 cases with cavernous transformation of the portal vein (CTPV). 1 case of simple upper gastro-intestinal tract (GIT) massive bleeding, 4 with refractory ascites and 11 with upper GIT massive bleeding and refractory ascites. Results: The procedure of TIPS was successful in 11 cases, the successful rate reached about 68.8%. The mean portal vein pressure was reduced from 4.9 kPa to 2.4 kPa with average 2. 5 kPa reduction. Ascites decreased, bleeding stopped and the clinical symptoms disappeared. The average survival period was 136 days. The procedure failed in 5 cases. Conclusions: TIPSS is an effective method to control the bleeding and ascites caused by PVCT. The PV cavernous transformation was the contraindication of TIPSS

  19. Anatomy of the Portal Vein Bifurcation: Implication for Transjugular Intrahepatic Portal Systemic Shunts

    International Nuclear Information System (INIS)

    Kwok, Philip Chong-hei; Ng, Wai Fu; Lam, Christine Suk-yee; Tsui, Polly Po; Faruqi, Asma

    2003-01-01

    Purpose: The relationship of the portalvein bifurcation to the liver capsule in Asians, which is an important landmark for transjugular intrahepatic portosystemic shunt, has not previously been described. Methods: The anatomy of the portal vein bifurcation was studied in 70 adult Chinese cadavers; it was characterized as intrahepatic or extrahepatic. The length of the exposed portion of the right and left portal veins was measured when the bifurcation was extrahepatic. Results: The portal vein bifurcation was intrahepatic in 37 cadavers (53%) and extrahepatic in 33 cadavers (47%). The mean length of the right and left extrahepatic portal veins was 0.96 cm and 0.85 cm respectively.Both were less than or equal to 2 cm in 94% of the cadavers with extrahepatic bifurcation. There was no correlation between the presence of cirrhosis and the location of the portal vein bifurcation(p 1.0). There was no statistically significant difference in liver mass in cadavers with either extrahepatic or intrahepatic bifurcation (p =0.40). Conclusions: These findings suggest that fortransjugular intrahepatic portosystemic shunt placement, a portal vein puncture 2 cm from the bifurcation will be safe in most cases

  20. Radioisotopic splenoportography in patients with portal hypertension

    International Nuclear Information System (INIS)

    Samejima, Natsuki; Ikeda, Koichiro; Yokoyama, Yasuhiro; Hirata, Satoru

    1989-01-01

    Radio-isotopic splenoportography was performed by injecting 99m TcO 4 - into the spleens of 46 patients with portal hypertension and 14 patients with various disorders not having portal hypertension. No collateral circulation was demonstrated in the 14 patients without portal hypertension whereas some RI-images of portosystemic collaterals were found in 40 (87.0 per cent) of the 46 patients with portal hypertension. Collaterals were divided into an ascending group and a descending group, the appearance rate of ascending collaterals being 80.4 per cent and that of descending collaterals, 41.3 per cent. There were 3 image patterns in the ascending group, namely, an AZ-pattern in which the azygos vein was demonstrated; a SC-pattern in which the RI-bolus ascended along the esophagus to the neck and the subclavian vein; and an EG-pattern which showed stagnation of the RI-bolus in the esophagogastric region. There were 4 patterns in the descending group, namely; a pattern of gastro-renal caval shunt (GR-pattern); reverse flow patterns into the umbilical or paraumbilical veins (UV-pattern); into the superior mesenteric vein (SMV-pattern); and into the inferior mesenteric vein (IMV-pattern). The appearance of the EG-pattern was seen most frequently (74.4 per cent). The usefulness of this method for surveying the collateral circulation in portal hypertension, estimating the risk of esophageal variceal bleeding and evaluating its treatments, was suggested by the results of this study. (author)

  1. CT of portal vein tumor thrombosis. Usefulness of dynamic CT

    Energy Technology Data Exchange (ETDEWEB)

    Takemoto, Kazumasa; Inoue, Yuichi; Tanaka, Masahiro; Nemoto, Yutaka; Nakamura, Kenji [Osaka City Univ. (Japan). Faculty of Medicine

    1983-08-01

    We evaluated CT findings of portal vein tumor thrombosis in 16 hepatomas by plain, contrast and dynamic CT. Plain and contrast CT findings were an enlargement of the portal vein (81%), intraluminal low density area (63%). Dynamic CT enhanced the diagnostic capability of the tumor thrombus as a relatively low density area because of the marked enhancement of the portal vein. In addition, dynamic CT newly demonstrated hyperdense peripheral ring (35%) and arterio portal shunt (35%). It is advisable to select the scan level to include the portal vein when dynamic CT is performed in the patient of hepatocellular carcinoma.

  2. Portal hypertension as portrayed by marked hepatosplenomegaly: case report

    International Nuclear Information System (INIS)

    Greene, R.A.

    1987-01-01

    The liver is vulnerable to as host of disease processes, including portal hypertension. This is a severe hepatic condition in which the liver is subject to numerous imbalances: increased hepatic blood flow, increased portal vein pressure due to extrahepatic portal vein obstruction, and/or increases in hepatic blood flow resistance. Although many diseases states may be responsible for the development of portal hypertension, it is most commonly associated with moderately severe or advanced cirrhosis. Advanced, untreated portal hypertension may cause additional complications such as hepatosplenomegaly, gastrointestinal bleeding, and ascites

  3. Splenomegaly, hyperkinetic splenic flow and portal hypertension in colitis

    Energy Technology Data Exchange (ETDEWEB)

    Friman, L [Serafimerlasarettet, Stockholm (Sweden)

    1980-01-01

    Four patients with a long history of colitis, splenomegaly, hypersplenism and portal hypertension were examined with angiography, both with contrast medium and isotopes, liver-spleen scintigraphy and recording of portal pressure. At angiography hyperkinetic splenic and portal blood flow was demonstrated. The increased flow causes increased portal pressure, which probably gives rise to changes in the liver often considered as slight cirrhosis at microscopy. The scintigraphic findings differed from Laennec cirrhosis. The liver uptake was homogeneous and no activity in the skeleton was recorded. Splenectomy cures both the hypersplenism and portal hypertension.

  4. Pathophysiology of Portal Hypertension and Its Clinical Links

    Science.gov (United States)

    Seo, Yeon Seok; Shah, Vijay H

    2011-01-01

    Portal hypertension is a major cause of morbidity and mortality in patients with liver cirrhosis. Intrahepatic vascular resistance due to architectural distortion and intrahepatic vasoconstriction, increased portal blood flow due to splanchnic vasodilatation, and development of collateral circulation have been considered as major factors for the development of portal hypertension. Recently, sinusoidal remodeling and angiogenesis have been focused as potential etiologic factors and various researchers have tried to improve portal hypertension by modulating these new targets. This article reviews potential new treatments in the context of portal hypertension pathophysiology concepts. PMID:25755320

  5. Splenomegaly, hyperkinetic splenic flow and portal hypertension in colitis

    International Nuclear Information System (INIS)

    Friman, L.

    1980-01-01

    Four patients with a long history of colitis, splenomegaly, hypersplenism and portal hypertension were examined with angiography, both with contrast medium and isotopes, liver-spleen scintigraphy and recording of portal pressure. At angiography hyperkinetic splenic and portal blood flow was demonstrated. The increased flow causes increased portal pressure, which probably gives rise to changes in the liver often considered as slight cirrhosis at microscopy. The scintigraphic findings differed from Laennec cirrhosis. The liver uptake was homogeneous and no activity in the skeleton was recorded. Splenectomy cures both the hypersplenism and portal hypertension. (Auth.)

  6. Analysis of Dynamic Characteristics of Portal Frame with Variable Section

    Directory of Open Access Journals (Sweden)

    Hao Jianing

    2016-01-01

    Full Text Available Combined with a portal frame design, by the use of finite element software ANSYS, the finite element model of single specimens of portal rigid frame and the overall portal rigid frame building are established. portal rigid frame’s beam and column is variable cross section. Through the modal analysis, comparative analysis of the frequency and vibration type of the radiolabeling specimens and finite element model of the whole, for the further development of variable cross-section portal rigid frame of earthquake and wind vibration analysis lay the foundation.

  7. Asian Network for Education in Nuclear Technology (ANENT). Report of the IAEA regional workshop on the development of a web-portal for ANENT

    International Nuclear Information System (INIS)

    2007-01-01

    information from the web-portal. Quality control of the information will be made at the national level, and also by using use rate assessment, survey, comments/feedback on NET DB, and periodic review. Views were solicited to consider future plans for upgrading the ANENT web-portal in the long term. They include: cyber platform, further development of subject-wise link (Taxonomy), introduction of more powerful S/W robot, functions specific to respective ANENT Group Activities. Some planning issues on workshops and the 2nd Coordination Committee Meeting which are expected in the second half of 2005 were discussed as well

  8. The NIDDK Information Network: A Community Portal for Finding Data, Materials, and Tools for Researchers Studying Diabetes, Digestive, and Kidney Diseases.

    Directory of Open Access Journals (Sweden)

    Patricia L Whetzel

    Full Text Available The NIDDK Information Network (dkNET; http://dknet.org was launched to serve the needs of basic and clinical investigators in metabolic, digestive and kidney disease by facilitating access to research resources that advance the mission of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK. By research resources, we mean the multitude of data, software tools, materials, services, projects and organizations available to researchers in the public domain. Most of these are accessed via web-accessible databases or web portals, each developed, designed and maintained by numerous different projects, organizations and individuals. While many of the large government funded databases, maintained by agencies such as European Bioinformatics Institute and the National Center for Biotechnology Information, are well known to researchers, many more that have been developed by and for the biomedical research community are unknown or underutilized. At least part of the problem is the nature of dynamic databases, which are considered part of the "hidden" web, that is, content that is not easily accessed by search engines. dkNET was created specifically to address the challenge of connecting researchers to research resources via these types of community databases and web portals. dkNET functions as a "search engine for data", searching across millions of database records contained in hundreds of biomedical databases developed and maintained by independent projects around the world. A primary focus of dkNET are centers and projects specifically created to provide high quality data and resources to NIDDK researchers. Through the novel data ingest process used in dkNET, additional data sources can easily be incorporated, allowing it to scale with the growth of digital data and the needs of the dkNET community. Here, we provide an overview of the dkNET portal and its functions. We show how dkNET can be used to address a variety of use cases

  9. The equivalency between logic Petri workflow nets and workflow nets.

    Science.gov (United States)

    Wang, Jing; Yu, ShuXia; Du, YuYue

    2015-01-01

    Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented.

  10. The Equivalency between Logic Petri Workflow Nets and Workflow Nets

    Science.gov (United States)

    Wang, Jing; Yu, ShuXia; Du, YuYue

    2015-01-01

    Logic Petri nets (LPNs) can describe and analyze batch processing functions and passing value indeterminacy in cooperative systems. Logic Petri workflow nets (LPWNs) are proposed based on LPNs in this paper. Process mining is regarded as an important bridge between modeling and analysis of data mining and business process. Workflow nets (WF-nets) are the extension to Petri nets (PNs), and have successfully been used to process mining. Some shortcomings cannot be avoided in process mining, such as duplicate tasks, invisible tasks, and the noise of logs. The online shop in electronic commerce in this paper is modeled to prove the equivalence between LPWNs and WF-nets, and advantages of LPWNs are presented. PMID:25821845

  11. Portal Vein Dopplerflowmetry in healthy sheep according to age

    Directory of Open Access Journals (Sweden)

    Alexandra F. Belotta

    Full Text Available ABSTRACT: Pulsed Doppler ultrasound was used to evaluate portal blood flow, portal velocity and portal congestion index in 24 healthy sheep divided into groups (lambs, yearlings and ewes, according to age. Measurements were performed at the 11th right intercostal space using ideal insonation angle and uniform insonation method. Mean values obtained in each group were compared with one-way ANOVA, followed by Tukey post-hoc test. Portal velocity and portal blood flow were statistically similar between the groups (P>0.05. Mean portal velocity were 17.75; 17.13 and 16.75; while mean portal blood flow were 26.65; 31.04 and 24.32 for lambs, yearlings and ewes, respectively. Portal congestion index was statistically distinct between the groups and values for lambs, yearlings and ewes were 0.009; 0.058 and 0.09, respectively (P<0.01. Statistical differences were observed in portal vein diameter, portal vein area and portal congestion index between the groups, presumably due to influence of weight and not to age.

  12. Art/Net/Work

    DEFF Research Database (Denmark)

    Andersen, Christian Ulrik; Lindstrøm, Hanne

    2006-01-01

    The seminar Art|Net|Work deals with two important changes in our culture. On one side, the network has become essential in the latest technological development. The Internet has entered a new phase, Web 2.0, including the occurrence of as ‘Wiki’s’, ‘Peer-2-Peer’ distribution, user controlled...... on the ‘network’ itself as a phenomenon and are often using technological networks as a mean of production and distribution. This changes the artistic practice and the distribution channels of art works – and the traditional notions of ‘work’, ‘origin’ and ‘rights’ are increasingly perceived as limiting...... the praxis of the artist. We see different kinds of interventions and activism (including ‘hacktivism’) using the network as a way of questioning the invisible rules that govern public and semi-public spaces. Who ‘owns’ them? What kind of social relationships do they generate? On what principle...

  13. Net4Care

    DEFF Research Database (Denmark)

    Christensen, Henrik Bærbak; Hansen, Klaus Marius

    2012-01-01

    , health centers are getting larger and more distributed, and the number of healthcare professionals does not follow the trend in chronic diseases. All of this leads to a need for telemedical and mobile health applications. In a Danish context, these applications are often developed through local...... (innovative) initiatives with little regards for national and global (standardization) initiatives. A reason for this discrepancy is that the software architecture for national (and global) systems and standards are hard to understand, hard to develop systems based on, and hard to deploy. To counter this, we...... propose a software ecosystem approach for telemedicine applications, providing a framework, Net4Care, encapsulating national/global design decisions with respect to standardization while allowing for local innovation. This paper presents an analysis of existing systems, of requirements for a software...

  14. Strategi Branding Portal Online Www.tripriau.com Dalam Membangun Brand Awareness Sebagai Portal Online Pariwisata Provinsi Riau

    OpenAIRE

    Rahmadhani, Yuri; Lubis, Evawani Elysa

    2017-01-01

    Online portal www.tripriau.com online portal is one of the online portal in Riau Province that has its own uniqueness. These portals contain local content and the potential of tourism in the province of Riau. Since its establishment, www.tripriau.com do branding strategy in order to build brand awareness or trust the reader to be known as a tourism-themed online portal. As the selection of brand name Trip Riau, Riau Guide My tagline, as well as the implementation of travel instagram photo con...

  15. Colangiopatía portal: complicación poco frecuente de la hipertensión portal

    OpenAIRE

    Veloso, Victoria; Servente, Liliana; Hernández, Nelia

    2017-01-01

    Resumen: Se describe el caso clínico de una mujer de 62 años en la que se diagnostica una estenosis del colédoco en el contexto de hipertensión portal prehepática (cavernomatosis portal). Abstract: We report the case of a 62 years old woman with a choledochal stricture and chronic obstruction of the portal vein (portal cavernomatosis). Resumo: Relatamos o caso de uma mulher de 62 anos com diagnóstico de estenose do colédoco no contexto da hipertensão portal pré-hepática (cavernomat...

  16. DES Science Portal: Computing Photometric Redshifts

    Energy Technology Data Exchange (ETDEWEB)

    Gschwend, Julia [LIneA, Rio de Janeiro

    2016-01-01

    An important challenge facing photometric surveys for cosmological purposes, such as the Dark Energy Survey (DES), is the need to produce reliable photometric redshifts (photo-z). The choice of adequate algorithms and configurations and the maintenance of an up-to-date spectroscopic database to build training sets, for example, are challenging tasks when dealing with large amounts of data that are regularly updated and constantly growing. In this paper, we present the first of a series of tools developed by DES, provided as part of the DES Science Portal, an integrated web-based data portal developed to facilitate the scientific analysis of the data, while ensuring the reproducibility of the analysis. We present the DES Science Portal photometric redshift tools, starting from the creation of a spectroscopic sample to training the neural network photo-z codes, to the final estimation of photo-zs for a large photometric catalog. We illustrate this operation by calculating well calibrated photo-zs for a galaxy sample extracted from the DES first year (Y1A1) data. The series of processes mentioned above is run entirely within the Portal environment, which automatically produces validation metrics, and maintains the provenance between the different steps. This system allows us to fine tune the many steps involved in the process of calculating photo-zs, making sure that we do not lose the information on the configurations and inputs of the previous processes. By matching the DES Y1A1 photometry to a spectroscopic sample, we define different training sets that we use to feed the photo-z algorithms already installed at the Portal. Finally, we validate the results under several conditions, including the case of a sample limited to i<22.5 with the color properties close to the full DES Y1A1 photometric data. This way we compare the performance of multiple methods and training configurations. The infrastructure presented here is an effcient way to test several methods of

  17. High-level Petri Nets

    DEFF Research Database (Denmark)

    various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets. Within the Petri net community this problem has been discussed many times, and as an outcome this book has been compiled. The book contains reprints...... of some of the most important papers on the application and theory of high-level Petri nets. In this way it makes the relevant literature more available. It is our hope that the book will be a useful source of information and that, e.g., it can be used in the organization of Petri net courses. To make......High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable descriptions than can be obtained by means...

  18. Improving diabetes management with a patient portal: a qualitative study of diabetes self-management portal.

    Science.gov (United States)

    Urowitz, Sara; Wiljer, David; Dupak, Kourtney; Kuehner, Zachary; Leonard, Kevin; Lovrics, Emily; Picton, Peter; Seto, Emily; Cafazzo, Joe

    2012-11-30

    Effective management and care of diabetes is crucial to reducing associated risks such as heart disease and kidney failure. With increasing access and use of the Internet, online chronic disease management is being explored as a means of providing patients with support and the necessary tools to monitor and manage their disease. The objective of our study was to evaluate the experience of patients and providers using an online diabetes management portal for patients. Participants were recruited from a large sample population of 887 for a follow-up questionnaire to be completed after 6 months of using the patient portal. Participants were presented with the option to participate in an additional interview and, if the participant agreed, a time and date was scheduled for the interview. A 5-item, open-ended questionnaire was used to capture providers' opinions of the patient portal. Providers included general practitioners (GPs), nurses, nurse practitioners (NPs), dieticians, diabetes educators (DECs), and other clinical staff. A total of 854 patients were consented for the questionnaire. Seventeen (8 male, 9 female) patients agreed to participate in a telephone interview. Sixty-four health care providers completed the five open-ended questions; however, an average of 48.2 responses were recorded per question. Four major themes were identified and will be discussed in this paper. These themes have been classified as: facilitators of disease management, barriers to portal use, patient-provider communication and relationship, and recommendations for portal improvements. This qualitative study shows that online chronic disease management portals increase patient access to information and engagement in their health care, but improvements in the portal itself may improve usability and reduce attrition. Furthermore, this study identifies a grey area that exists in the roles that GPs and AHPs should play in the facilitation of online disease management.

  19. Net neutrality and audiovisual services

    OpenAIRE

    van Eijk, N.; Nikoltchev, S.

    2011-01-01

    Net neutrality is high on the European agenda. New regulations for the communication sector provide a legal framework for net neutrality and need to be implemented on both a European and a national level. The key element is not just about blocking or slowing down traffic across communication networks: the control over the distribution of audiovisual services constitutes a vital part of the problem. In this contribution, the phenomenon of net neutrality is described first. Next, the European a...

  20. NetView technical research

    Science.gov (United States)

    1993-01-01

    This is the Final Technical Report for the NetView Technical Research task. This report is prepared in accordance with Contract Data Requirements List (CDRL) item A002. NetView assistance was provided and details are presented under the following headings: NetView Management Systems (NMS) project tasks; WBAFB IBM 3090; WPAFB AMDAHL; WPAFB IBM 3084; Hill AFB; McClellan AFB AMDAHL; McClellan AFB IBM 3090; and Warner-Robins AFB.

  1. Initial CAD investigations for NET

    International Nuclear Information System (INIS)

    Katz, F.; Leinemann, K.; Ludwig, A.; Marek, U.; Olbrich, W.; Schlechtendahl, E.G.

    1985-11-01

    This report summarizes the work done under contract no. 164/84-7/FU-D-/NET between the Commission of the European Communities and KfK during the period from June 1, 1984, through May 31, 1985. The following topics are covered in this report: Initial modelling of NET version NET2A, CAD system extension for remote handling studies, analysis of the CAD information structure, work related to the transfer of CAD information between KfK and the NET team. (orig.) [de

  2. Understanding Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Salom, Jaume; Widén, Joakim; Candanedo, José

    2011-01-01

    Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid...

  3. Portal hypertensive polyps, a new entity?

    Directory of Open Access Journals (Sweden)

    Verónica Martín-Domínguez

    Full Text Available Presentamos el caso clínico de una mujer de 62 años de edad, con antecedentes de cirrosis hepática secundaria a hepatitis autoinmune, hipertensión portal y coagulopatía, quien presenta en gastroscopia, unas lesiones polipoideas, semipediculadas, polilobuladas en la región prepilórica, que se extirpan y cuya anatomía patológica se describe como pólipos hiperplásicos con edema, congestión vascular e hiperplasia del músculo liso, sin displasia ni cambios adenomatosos, correspondientes a "pólipos de la hipertensión portal" (PHP.

  4. Novel treatment options for portal hypertension

    Science.gov (United States)

    Laleman, Wim

    2017-01-01

    Abstract Portal hypertension is most frequently associated with cirrhosis and is a major driver for associated complications, such as variceal bleeding, ascites or hepatic encephalopathy. As such, clinically significant portal hypertension forms the prelude to decompensation and impacts significantly on the prognosis of patients with liver cirrhosis. At present, non-selective β-blockers, vasopressin analogues and somatostatin analogues are the mainstay of treatment but these strategies are far from satisfactory and only target splanchnic hyperemia. In contrast, safe and reliable strategies to reduce the increased intrahepatic resistance in cirrhotic patients still represent a pending issue. In recent years, several preclinical and clinical trials have focused on this latter component and other therapeutic avenues. In this review, we highlight novel data in this context and address potentially interesting therapeutic options for the future. PMID:28533907

  5. Portal Vein Embolization: What Do We Know?

    Energy Technology Data Exchange (ETDEWEB)

    Denys, Alban, E-mail: Alban.Denys@chuv.ch [Centre Hospitalo Universitaire Vaudois, Department of Radiology and Interventional Radiology Unit (Switzerland); Prior, John [Centre Hospitalo Universitaire Vaudois, Department of Nuclear Medicine (Switzerland); Bize, Pierre; Duran, Rafael [Centre Hospitalo Universitaire Vaudois, Department of Radiology and Interventional Radiology Unit (Switzerland); Baere, Thierry De [Institut Gustave Roussy, Department of Interventional Radiology (France); Halkic, Nermin; Demartines, Nicolas [Centre Hospitalo Universitaire Vaudois, Department of Visceral Surgery (Switzerland)

    2012-10-15

    Portal vein embolization (PVE) has been developed to increase the size of the future remnant liver (FRL) left in place after major hepatectomy, thus reducing the risk of postoperative liver insufficiency. PVE consist in embolizing preoperatively portal branches of the segments that will be resected. Indication is based on preoperative measurements of the FRL by computed tomography and its ratio with either the theoretical liver volume or by direct measurement of the functional liver volume. After PVE, the volume and function of the FRL increases in 3 to 6 weeks, permitting extensive resections in patients otherwise contraindicated for liver resection. The PVE technique is variable from one center to another; however n-butyl-cyano-acrylate provides an interesting compromise between hypertrophy rate and procedure risk.

  6. Spin-0± portal induced Dark Matter

    Science.gov (United States)

    Dutta, Sukanta; Goyal, Ashok; Saini, Lalit Kumar

    2018-02-01

    Standard model (SM) spin-zero singlets are constrained through their di-Bosonic decay channels via an effective coupling induced by a vector-like quark (VLQ) loop at the LHC for √{s}=13 TeV. These spin-zero resonances are then considered as portals for scalar, vector or fermionic dark matter particle interactions with SM gauge bosons. We find that the model is validated with respect to the observations from LHC data and from cosmology, indirect and direct detection experiments for an appreciable range of scalar, vector and fermionic DM masses greater than 300 GeV and VLQ masses ≥ 400 GeV, corresponding to the three choice of portal masses 270 GeV, 500 GeV and 750 GeV respectively.

  7. An analysis of splenoportographic findings in portal hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Eun Mi; Moon, Sook Ran; Kim, Han Suk [National Medical Center, Seoul (Korea, Republic of); Park, Soo Soung [College of Medicine, Chung Ang University, Seoul (Korea, Republic of)

    1983-12-15

    Splenoportography has been proved as a useful method for the evaluation of circulatory disturbances in portal hypertension. Authors analyzed the various aspects of these disturbance on splenoportography in 22 cases that was performed under the clinical suspicion of portal hypertension during recent 6 years, from May, 1976 to July 1982 at the Department of Radiology, National Medical Center. The results were as follows: 1. Liver cirrhosis was the most frequent cause of intrahepatic obstruction type in portal hypertension (86%). 2. The portal pressure was more than 400 mmH{sub 2}0 in 67% of the cases (range; 300-540 mmH{sub 2}0). 3. In the majority of the cases, the higher the portal pressure was, the more dilated splenic and portal veins were. The diameter of portal vein was more than 15 mm in 79%, more than 21 mm in 47% of the cases (range; 10-26 mm). The diameter of splenic vein was more than 15 mm in 48% of the cases (range; 7-23 mm). Especially the diameter of splenic vein was larger than that of portal vein in 20% of the cases. 4. There was no definite correlation between the development of collateral circulation and the diameter of splenic and portal veins. 5. The filling of collateral circulation was definite sign of portal hypertension, though not regular. In portal hypertension, the collateral circulation was formed via coronary vein (91%), short gastric vein (64%), inferior mesenteric vein (36%). 6. Splenic-hilum time was delayed in 64% of the cases. Intrahepatic portal vein emptying time was more than 6 seconds in all the cases. 7. Most of the cases (91%) could be diagnosed as portal hypertension with vasculogram and hepatogram.

  8. An analysis of splenoportographic findings in portal hypertension

    International Nuclear Information System (INIS)

    Jung, Eun Mi; Moon, Sook Ran; Kim, Han Suk; Park, Soo Soung

    1983-01-01

    Splenoportography has been proved as a useful method for the evaluation of circulatory disturbances in portal hypertension. Authors analyzed the various aspects of these disturbance on splenoportography in 22 cases that was performed under the clinical suspicion of portal hypertension during recent 6 years, from May, 1976 to July 1982 at the Department of Radiology, National Medical Center. The results were as follows: 1. Liver cirrhosis was the most frequent cause of intrahepatic obstruction type in portal hypertension (86%). 2. The portal pressure was more than 400 mmH 2 0 in 67% of the cases (range; 300-540 mmH 2 0). 3. In the majority of the cases, the higher the portal pressure was, the more dilated splenic and portal veins were. The diameter of portal vein was more than 15 mm in 79%, more than 21 mm in 47% of the cases (range; 10-26 mm). The diameter of splenic vein was more than 15 mm in 48% of the cases (range; 7-23 mm). Especially the diameter of splenic vein was larger than that of portal vein in 20% of the cases. 4. There was no definite correlation between the development of collateral circulation and the diameter of splenic and portal veins. 5. The filling of collateral circulation was definite sign of portal hypertension, though not regular. In portal hypertension, the collateral circulation was formed via coronary vein (91%), short gastric vein (64%), inferior mesenteric vein (36%). 6. Splenic-hilum time was delayed in 64% of the cases. Intrahepatic portal vein emptying time was more than 6 seconds in all the cases. 7. Most of the cases (91%) could be diagnosed as portal hypertension with vasculogram and hepatogram

  9. Computed tomographic evaluation of the portal vein in the hepatomas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kee Hyung; Lee, Seung Chul; Bae, Man Gil; Seo, Heung Suk; Kim, Soon Yong; Lee, Min Ho; Kee, Choon Suhk; Park, Kyung Nam [Hanyang University College of Medicine, Seoul (Korea, Republic of)

    1986-10-15

    Computed tomography and pornographic findings of 63 patients with hepatoma, undergone hepatic angiography and superior mesenteric pornography for evaluation of tumor and thrombosis of portal vein and determination of indication of transcatheter arterial embolization for palliative treatment of hepatoma from April, 85 to June, 86 in Hanyang university hospital, were reviewed. The results were as follows: 1. In 36 cases, portal vein thrombosis was detected during photography. Nineteen of 37 cases which revealed localized hepatoma in the right lobe of the liver showed portal vein thrombosis; 9 of 11 cases of the left lobe; 8 of 14 cases which were involved in entire liver revealed thrombosis. One case localized in the caudate lobe showed no evidence of invasion to portal vein. 2. Twenty-four of 34 cases with diffuse infiltrative hepatoma revealed portal vein thrombosis and the incidence of portal vein thrombosis in this type were higher than in the cases of the nodular type. 3. The portal vein thrombosis appeared as filling defects of low density in the lumen of the portal veins in CT and they did not reveal contrast enhancement. 4. CT revealed well the evidence of obstructions in the cases of portal vein thrombosis and the findings were well-corresponded to the findings of the superior mesenteric photography. 5. Five of the cases of the portal vein thrombosis were missed in the CT and the causes were considered as due to partial volume effect of enhanced portal vein with partial occlusion or arterioportal shunts. 6. Six of 13 cases with occlusion of main portal vein showed cavernous transformation and they were noted as multiple small enhanced vascularities around the porta hepatis in the CT. According to the results, we conclude that CT is a useful modality to detect the changes of the portal veins in the patients of the hepatoma.

  10. Computed tomographic evaluation of the portal vein in the hepatomas

    International Nuclear Information System (INIS)

    Lee, Kee Hyung; Lee, Seung Chul; Bae, Man Gil; Seo, Heung Suk; Kim, Soon Yong; Lee, Min Ho; Kee, Choon Suhk; Park, Kyung Nam

    1986-01-01

    Computed tomography and pornographic findings of 63 patients with hepatoma, undergone hepatic angiography and superior mesenteric pornography for evaluation of tumor and thrombosis of portal vein and determination of indication of transcatheter arterial embolization for palliative treatment of hepatoma from April, 85 to June, 86 in Hanyang university hospital, were reviewed. The results were as follows: 1. In 36 cases, portal vein thrombosis was detected during photography. Nineteen of 37 cases which revealed localized hepatoma in the right lobe of the liver showed portal vein thrombosis; 9 of 11 cases of the left lobe; 8 of 14 cases which were involved in entire liver revealed thrombosis. One case localized in the caudate lobe showed no evidence of invasion to portal vein. 2. Twenty-four of 34 cases with diffuse infiltrative hepatoma revealed portal vein thrombosis and the incidence of portal vein thrombosis in this type were higher than in the cases of the nodular type. 3. The portal vein thrombosis appeared as filling defects of low density in the lumen of the portal veins in CT and they did not reveal contrast enhancement. 4. CT revealed well the evidence of obstructions in the cases of portal vein thrombosis and the findings were well-corresponded to the findings of the superior mesenteric photography. 5. Five of the cases of the portal vein thrombosis were missed in the CT and the causes were considered as due to partial volume effect of enhanced portal vein with partial occlusion or arterioportal shunts. 6. Six of 13 cases with occlusion of main portal vein showed cavernous transformation and they were noted as multiple small enhanced vascularities around the porta hepatis in the CT. According to the results, we conclude that CT is a useful modality to detect the changes of the portal veins in the patients of the hepatoma.

  11. Inpatient Portals for Hospitalized Patients and Caregivers: A Systematic Review.

    Science.gov (United States)

    Kelly, Michelle M; Coller, Ryan J; Hoonakker, Peter Lt

    2018-06-01

    Patient portals, web-based personal health records linked to electronic health records (EHRs), provide patients access to their healthcare information and facilitate communication with providers. Growing evidence supports portal use in ambulatory settings; however, only recently have portals been used with hospitalized patients. Our objective was to review the literature evaluating the design, use, and impact of inpatient portals, which are patient portals designed to give hospitalized patients and caregivers inpatient EHR clinical information for the purpose of engaging them in hospital care. Literature was reviewed from 2006 to 2017 in PubMed, Web of Science, CINALPlus, Cochrane, and Scopus to identify English language studies evaluating patient portals, engagement, and inpatient care. Data were analyzed considering the following 3 themes: inpatient portal design, use and usability, and impact. Of 731 studies, 17 were included, 9 of which were published after 2015. Most studies were qualitative with small samples focusing on inpatient portal design; 1 nonrandomized trial was identified. Studies described hospitalized patients' and caregivers' information needs and design recommendations. Most patient and caregiver participants in included studies were interested in using an inpatient portal, used it when offered, and found it easy to use and/or useful. Evidence supporting the role of inpatient portals in improving patient and caregiver engagement, knowledge, communication, and care quality and safety is limited. Included studies indicated providers had concerns about using inpatient portals; however, the extent to which these concerns have been realized remains unclear. Inpatient portal research is emerging. Further investigation is needed to optimally design inpatient portals to maximize potential benefits for hospitalized patients and caregivers while minimizing unintended consequences for healthcare teams. © 2017 Society of Hospital Medicine.

  12. Diavideos: a diabetes health video portal.

    Science.gov (United States)

    Sánchez-Bocanegra, C L; Rivero-Rodriguez, A; Fernández-Luque, L; Sevillano, J L

    2013-01-01

    Diavideos is a web platform that collects trustworthy diabetes health videos from YouTube and offers them in a easy way. YouTube is a big repository of health videos, but good content is sometimes mixed with misleading and harmful videos such as promoting anorexia [1]. Diavideos is a web portal that provides easy access to a repository of trustworthy diabetes videos. This poster describes Diavideos and explains the crawling method used to retrieve these videos from trusted channels.

  13. Liferay 6.x portal enterprise intranets cookbook

    CERN Document Server

    Filipowicz, Piotr

    2015-01-01

    If you are a Java developer or administrator with a technical background and want to install and configure Liferay Portal as an enterprise intranet, this is the book for you. In short, reusable recipes help you realize business goals as working features in Liferay. This book will also give you useful hints on how to easily improve the default functionality of the system and its performance.

  14. State of the SOOS GCMD Portal

    Science.gov (United States)

    Ritz, Scott

    2018-01-01

    A brief status update on NASA’s latest Global Change Master Directory (GCMD) keyword update, description of the differences between DIF-9 and DIF-10 formats in advance of the deprecation of DIF-9 support in Earth Observing System Data and Information System (EOSDIS) with specifics on the DIF-10.3 schema, transition schedule, and some usage metrics for the GCMD Southern Ocean Observing System (SOOS) Portal.

  15. Comparative methods of concrete portal frame design

    OpenAIRE

    A, Letengsang

    2014-01-01

    The objective of this thesis was to design a concrete portal frame with two column spacings of 12 meters and 6 meters and its structural elements in a building located in Hämeenlinna city, Finland. A comprehension study on the concrete design chapter of Eurocode 2 was done before proceeding on the calculation process, the materials’ properties. The corresponding ca-pacity diagrams from concrete product manufacturers in Finland can be assistance tools during the calculation process. ...

  16. Portal verification for breast cancer radiotherapy

    International Nuclear Information System (INIS)

    Petkovska, Sonja; Pejkovikj, Sasho; Apostolovski, Nebojsha

    2013-01-01

    At the University Clinic in Skopje, breast cancer irradiation is being planned and performed by using a mono-iso centrical method, which means that a unique isocenter (I C) for all irradiation fields is used. The goal of this paper is to present the patient’s position in all coordinates before the first treatment session, relative to the position determined during the CT simulation. Deviation of up to 5 mm is allowed. The analysis was made by using a portal verification. Sixty female patients at random selection are reviewed. The matching results show that for each patient deviation exists at least on one axis. The largest deviations are in the longitudinal direction (head-feet) up to 4 mm, mean 1.8 mm. In 60 out of 85 analysed fields, the deviation is towards the head. In lateral direction, median deviation is 1.1 mm and in 65% of the analysed portals those deviations are in medial direction – contralateral breast which can increases the dose in the lung and in the contralateral breast. This deviation for supraclavicular field can increase the dose in the spinal cord. Although these doses are well below the limit, this fact should be taken into account in setting the treatment fields. The final conclusion from the research is that despite of the fact we are dealing with small deviations, in conditions when accuracy in positioning is done with portal, the portal verification needs to be done in the coming weeks of the treatment, not only before the first treatment. This provides information for an intra fractional set-up deviation. (Author)

  17. Rare, but challenging tumors: NET

    International Nuclear Information System (INIS)

    Ivanova, D.; Balev, B.

    2013-01-01

    Full text: Introduction: Gastroenteropancreatic Neuroendocrine Tumors (GEP - NET) are a heterogeneous group of tumors with different locations and many different clinical, histological, and imaging performance. In a part of them a secretion of various organic substances is present. The morbidity of GEP - NET in the EU is growing, and this leads to increase the attention to them. What you will learn: Imaging methods used for localization and staging of GEP - NET, characteristics of the study’s protocols; Classification of GEP - NET; Demonstration of typical and atypical imaging features of GEP - NET in patients registered at the NET Center at University Hospital ‘St. Marina’, Varna; Features of metastatic NET, The role of imaging in the evaluation of treatment response and follow-up of the patients. Discussion: The image semiotics analysis is based on 19 cases of GEP - NET registered NET Center at University Hospital ‘St. Marina’. The main imaging method is multidetector CT (MDCT), and magnetic resonance imaging (MRI ) has advantages in the evaluation of liver lesions and the local prevalence of anorectal tumors. In patients with advanced disease and liver lesions the assessment of skeletal involvement (MRI/ nuclear medical method) is mandatory. The majority of GEP - NET have not any specific imaging findings. Therefore it is extremely important proper planning and conducting of the study (MDCT and MR enterography; accurate assessment phase of scanning, positive and negative contrast). Conclusion: GEP - NET is a major diagnostic challenge due to the absence of typical imaging characteristics and often an overlap with those of the tumors of different origin can be observed. Therefore, a good knowledge of clinical and imaging changes occurring at different locations is needed. MDCT is the basis for the diagnosis, staging and follow-up of these neoplasms

  18. Landscape analysis of soil methane flux across complex terrain

    Science.gov (United States)

    Kaiser, Kendra E.; McGlynn, Brian L.; Dore, John E.

    2018-05-01

    Relationships between methane (CH4) fluxes and environmental conditions have been extensively explored in saturated soils, while research has been less prevalent in aerated soils because of the relatively small magnitudes of CH4 fluxes that occur in dry soils. Our study builds on previous carbon cycle research at Tenderfoot Creek Experimental Forest, Montana, to identify how environmental conditions reflected by topographic metrics can be leveraged to estimate watershed scale CH4 fluxes from point scale measurements. Here, we measured soil CH4 concentrations and fluxes across a range of landscape positions (7 riparian, 25 upland), utilizing topographic and seasonal (29 May-12 September) gradients to examine the relationships between environmental variables, hydrologic dynamics, and CH4 emission and uptake. Riparian areas emitted small fluxes of CH4 throughout the study (median: 0.186 µg CH4-C m-2 h-1) and uplands increased in sink strength with dry-down of the watershed (median: -22.9 µg CH4-C m-2 h-1). Locations with volumetric water content (VWC) below 38 % were methane sinks, and uptake increased with decreasing VWC. Above 43 % VWC, net CH4 efflux occurred, and at intermediate VWC net fluxes were near zero. Riparian sites had near-neutral cumulative seasonal flux, and cumulative uptake of CH4 in the uplands was significantly related to topographic indices. These relationships were used to model the net seasonal CH4 flux of the upper Stringer Creek watershed (-1.75 kg CH4-C ha-1). This spatially distributed estimate was 111 % larger than that obtained by simply extrapolating the mean CH4 flux to the entire watershed area. Our results highlight the importance of quantifying the space-time variability of net CH4 fluxes as predicted by the frequency distribution of landscape positions when assessing watershed scale greenhouse gas balances.

  19. Turbulent transport across invariant canonical flux surfaces

    International Nuclear Information System (INIS)

    Hollenberg, J.B.; Callen, J.D.

    1994-07-01

    Net transport due to a combination of Coulomb collisions and turbulence effects in a plasma is investigated using a fluid moment description that allows for kinetic and nonlinear effects via closure relations. The model considered allows for ''ideal'' turbulent fluctuations that distort but preserve the topology of species-dependent canonical flux surfaces ψ number-sign,s triple-bond ∫ dF · B number-sign,s triple-bond ∇ x [A + (m s /q s )u s ] in which u s is the flow velocity of the fluid species. Equations for the net transport relative to these surfaces due to ''nonideal'' dissipative processes are found for the total number of particles and total entropy enclosed by a moving canonical flux surface. The corresponding particle transport flux is calculated using a toroidal axisymmetry approximation of the ideal surfaces. The resulting Lagrangian transport flux includes classical, neoclassical-like, and anomalous contributions and shows for the first time how these various contributions should be summed to obtain the total particle transport flux

  20. Exploratory portals of research data in education

    Directory of Open Access Journals (Sweden)

    Di Blas Nicoletta

    2015-12-01

    Full Text Available This paper presents a powerful tool to enhance research in education: ‘exploratory portals’, supporting effective storage, sharing and exploration of large sets of research data. The workflow is the following: data are gathered by a research group; they are then classified according to a taxonomy (the one that best fits the group’s research interest; once uploaded in the portal, they can be ‘explored’ via a combination of faceted search (enriched by Boolean operators and data mining techniques. The system can thus answer in a few seconds to sophisticated user’s queries that otherwise would require hours; it can save a session’s results and materials for sharing with other scholars or for further investigation. The paper presents a case study of exploratory portal, dealing with data on (technology-based education. The portal has effectively been used by five different research groups, to run complex investigations of data about technology integration into schools.

  1. Idiopathic non-cirrhotic portal hypertension

    Directory of Open Access Journals (Sweden)

    CHEN Jie

    2013-07-01

    Full Text Available The pathogenesis of idiopathic non-cirrhotic portal hypertension (INCPH remains unknown and the disease is diagnosed by the absence of recognized clinical indicators of cirrhosis and of any other known etiologies of portal hypertension. To promote understanding of this disease, a comprehensive overview of potential etiologies, clinical manifestations, histopathological features, methods of diagnosis and potential differential diagnoses, and outcome of clinical management is presented in this review. In particular, we discuss the findings from INCPH studies and their implications in regards to each of the above-mentioned categories. For example, associations with various comorbidities have suggested a possible immune system component to INCPH development and/or progression. In addition, the common clinical characteristics of patients upon presentation can not only help to recognize disease suspects but may also provide insights into the pathogenesis and prognosis. Finally, prognosis following the various intervention strategies appears to depend mainly on severity of the portal hypertension, as well as its various accompanying complications.

  2. The DIRAC Web Portal 2.0

    Science.gov (United States)

    Mathe, Z.; Casajus Ramo, A.; Lazovsky, N.; Stagni, F.

    2015-12-01

    For many years the DIRAC interware (Distributed Infrastructure with Remote Agent Control) has had a web interface, allowing the users to monitor DIRAC activities and also interact with the system. Since then many new web technologies have emerged, therefore a redesign and a new implementation of the DIRAC Web portal were necessary, taking into account the lessons learnt using the old portal. These new technologies allowed to build a more compact, robust and responsive web interface that enables users to have better control over the whole system while keeping a simple interface. The web framework provides a large set of “applications”, each of which can be used for interacting with various parts of the system. Communities can also create their own set of personalised web applications, and can easily extend already existing ones with a minimal effort. Each user can configure and personalise the view for each application and save it using the DIRAC User Profile service as RESTful state provider, instead of using cookies. The owner of a view can share it with other users or within a user community. Compatibility between different browsers is assured, as well as with mobile versions. In this paper, we present the new DIRAC Web framework as well as the LHCb extension of the DIRAC Web portal.

  3. Grid Portal for Image and Video Processing

    International Nuclear Information System (INIS)

    Dinitrovski, I.; Kakasevski, G.; Buckovska, A.; Loskovska, S.

    2007-01-01

    Users are typically best served by G rid Portals . G rid Portals a re web servers that allow the user to configure or run a class of applications. The server is then given the task of authentication of the user with the Grid and invocation of the required grid services to launch the user's application. PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML. PHP is powerful and modern server-side scripting language producing HTML or XML output which easily can be accessed by everyone via web interface (with the browser of your choice) and can execute shell scripts on the server side. The aim of our work is development of Grid portal for image and video processing. The shell scripts contains gLite and globus commands for obtaining proxy certificate, job submission, data management etc. Using this technique we can easily create web interface to the Grid infrastructure. The image and video processing algorithms are implemented in C++ language using various image processing libraries. (Author)

  4. Interventional Radiologic Treatment for Idiopathic Portal Hypertension

    International Nuclear Information System (INIS)

    Hirota, Shozo; Ichikawa, Satoshi; Matsumoto, Shinichi; Motohara, Tomofumi; Fukuda, Tetsuya; Yoshikawa, Takeshi

    1999-01-01

    Purpose: To evaluate the usefulness of interventional radiological treatment for idiopathic portal hypertension. Methods: Between 1995 and 1998, we performed an interventional radiological treatment in five patients with idiopathic portal hypertension, four of whom had refused surgery and one of whom had undergone surgery. Three patients with gastroesophageal varices (GEV) were treated by partial splenic embolization (PSE), one patient with esophageal varices (EV) and massive ascites by transjugular intrahepatic portosytemic shunt (TIPS) and PSE, and one patient with GEV by percutaneous transhepatic obliteration (PTO). Midterm results were analyzed in terms of the effect on esophageal and/or gastric varices. Results: In one woman with severe GEV who underwent three sessions of PSE, there was endoscopic confirmation that the GEV had disappeared. In one man his EV shrunk markedly after two sessions of PSE. In two patients slight reduction of the EV was obtained with one application of PSE combined with endoscopic variceal ligation therapy. PTO for GV in one patient resulted in good control of the varices. All patients have survived for 16-42 months since the first interventional treatment, and varices are well controlled. Conclusion: Interventional radiological treatment is effective for patients with idiopathic portal hypertension, whether or not they have undergone surgery

  5. Magnetic-flux pump

    Science.gov (United States)

    Hildebrandt, A. F.; Elleman, D. D.; Whitmore, F. C. (Inventor)

    1966-01-01

    A magnetic flux pump is described for increasing the intensity of a magnetic field by transferring flux from one location to the magnetic field. The device includes a pair of communicating cavities formed in a block of superconducting material, and a piston for displacing the trapped magnetic flux into the secondary cavity producing a field having an intense flux density.

  6. Radon flux measurement methodologies

    International Nuclear Information System (INIS)

    Nielson, K.K.; Rogers, V.C.

    1984-01-01

    Five methods for measuring radon fluxes are evaluated: the accumulator can, a small charcoal sampler, a large-area charcoal sampler, the ''Big Louie'' charcoal sampler, and the charcoal tent sampler. An experimental comparison of the five flux measurement techniques was also conducted. Excellent agreement was obtained between the measured radon fluxes and fluxes predicted from radium and emanation measurements

  7. Transjugular intrahepatic portosystemic shunt in patients with active variceal bleeding due to portal hypertension and portal vein thrombosis

    International Nuclear Information System (INIS)

    Shin, Hyun Woong; Ryeom, Hun Kyu; Lee, Sang Kwon; Lee, Jong Min; Kim, Young Sun; Suh, Kyung Jin; Kim, Tae Hun; Kim, Yong Joo

    1997-01-01

    To evaluate the feasibility and efficacy of transjugular intrahepatic portosystemic shunt (TIPS) in patients with active variceal bleeding due to liver cirrhosis and pre-existing portal vein thrombosis. Of a total of 123 patients who underwent TIPS, 14 patients with intractable variceal bleeding due to portal hypertension and portal vein thrombosis were included in this study. Noncavernomatous portal vein occlusion was seen in eight patients, and complete portal vein occlusion with cavernomatous trans-formation in six. For all patients, the methods used for TIPS placement were the same as those used in patients with patents portal veins. In seven of eight patients with noncavernomatous occlusion, right hepatic vein-right portal vein shunting was performed; in one with knoncavernomatous occlusion, a shunt was created between the right hepatic and left portal vein. In five of six patients with cavernomatous occlusion, the right hepatic and main portal vein were connected via a collateral vein. The procedures were technically successful in all except one patient. Immediate hemostatis was achieved after all technically successful procedures, and no significant complications were encountered. Minor complications were noted in six patients (three biliary tree punctures, one transperitoneal puncture, one splenic vein perforation, one hepatic subcapsular hematoma). TIPS is a technically feasible and hemodynamically effective procedure, even in patients with active variceal bleeding due to cirrhosis and complete portal vein occlusion

  8. Linear Logic on Petri Nets

    DEFF Research Database (Denmark)

    Engberg, Uffe Henrik; Winskel, Glynn

    This article shows how individual Petri nets form models of Girard's intuitionistic linear logic. It explores questions of expressiveness and completeness of linear logic with respect to this interpretation. An aim is to use Petri nets to give an understanding of linear logic and give some apprai...

  9. Net neutrality and audiovisual services

    NARCIS (Netherlands)

    van Eijk, N.; Nikoltchev, S.

    2011-01-01

    Net neutrality is high on the European agenda. New regulations for the communication sector provide a legal framework for net neutrality and need to be implemented on both a European and a national level. The key element is not just about blocking or slowing down traffic across communication

  10. Índice de congestão portal e a ocorrência de trombose portal pós-dape Portal congestion and thrombosis after EDS

    Directory of Open Access Journals (Sweden)

    Fabio Gonçalves Ferreira

    2005-08-01

    Full Text Available OBJETIVO: Comparar os dados obtidos pela ultra-sonografia com doppler no pré-operatório de esquistossomóticos submetidos à desconexão ázigo-portal com esplenectomia (DAPE, calculando o índice de congestão portal, e sua correlação com a trombose portal no pós-operatório. MÉTODOS: Foram estudados 65 pacientes submetidos à DAPE por hipertensão portal esquistossomótica com antecedente de hemorragia digestiva, divididos em dois grupos: Grupo A (28 pacientes que não desenvolveram trombose portal pós-operatória e Grupo B (37 pacientes com trombose portal no pós-operatório. Analisaram-se através de ultra-sonografia com doppler no pré-operatório os seguintes parâmetros da veia porta: diâmetro, área, velocidade média de fluxo do sangue, fluxo de sangue, e estabeleceu-se o índice de congestão portal. RESULTADOS: O diâmetro, área e o fluxo da veia porta foram maiores no grupo B (média de 1,52 cm; 1,77 cm² e 2533,12 ml/min em relação ao grupo A (média de 1,33 cm; 1,44 cm² e 1609,03 ml/min com p = 0,03; 0,03 e 0,04 respectivamente. O índice de congestão portal não foi estatisticamente significativo na comparação dos dois grupos (p = 0,07. CONCLUSÃO: O índice de congestão portal obtido no pré-operatório através da ultra-sonografia com doppler não se mostrou preditivo de trombose portal no pós-operatório dos doentes estudados.BACKGROUND: The study compared the preoperative portal vein congestion index estimated by Doppler ultrasound and the postoperative portal vein thrombosis of patients submitted to esophagogastric devascularization and splenectomy (EDS. METHODS: 65 patients with portal hypertension due to schistosomiasis and previous gastrointestinal bleeding submitted to EDS were divided into two groups: GROUP A (28 patients without postoperative portal vein thrombosis and GROUP B (37 patients with postoperative portal vein thrombosis. The following parameters of preoperative Doppler ultrasound of the

  11. Properties of porous netted materials

    International Nuclear Information System (INIS)

    Daragan, V.D.; Drozdov, B.G.; Kotov, A.Yu.; Mel'nikov, G.N.; Pustogarov, A.V.

    1987-01-01

    Hydraulic and strength characteristics, efficient heat conduction and inner heat exchange coefficient are experimentally studied for porous netted materials on the base of the brass nets as dependent on porosity, cell size and method of net laying. Results of the studies are presented. It is shown that due to anisotropy of the material properties the hydraulic resistance in the direction parallel to the nets plane is 1.3-1.6 times higher than in the perpendicular one. Values of the effective heat conduction in the direction perpendicular to the nets plane at Π>0.45 agree with the data from literature, at Π<0.45 a deviation from the calculated values is marked in the direction of the heat conduction decrease

  12. TMEM16A regulates portal vein smooth muscle cell proliferation in portal hypertension.

    Science.gov (United States)

    Zeng, Xi; Huang, Ping; Chen, Mingkai; Liu, Shiqian; Wu, Nannan; Wang, Fang; Zhang, Jing

    2018-01-01

    The aim of the present study was to elucidate the effect of transmembrane protein 16A (TMEM16A) on portal vein smooth muscle cell (PVSMC) proliferation associated with portal vein remodeling in portal hypertension (PHT). Sprague-Dawley rats were subjected to bile duct ligation to establish a rat model of liver cirrhosis and PHT. Sham-operated animals served as controls. At 8 weeks after bile duct ligation, the extent of liver fibrosis and the portal vein wall thickness were assessed using hematoxylin-eosin staining. The protein expression levels of TMEM16A, extracellular signal-regulated kinase 1 and 2 (ERK1/2) and phosphorylated ERK1/2 (p-ERK1/2) in the portal vein were detected by immunohistochemistry and western blotting. In vitro , the lentivirus vectors were constructed and transfected into PVSMCs to upregulate the expression of TMEM16A. Isolated rat primary PVSMCs were treated with a small molecule inhibitor of TMEM16A, T16A-inhA01. Cell cycle was detected by flow cytometry. The activity of TMEM16A in the portal vein isolated from bile duct ligated rats was decreased, while the expression level of p-ERK1/2 was increased. However, in vitro , upregulation of TMEM16A promoted the proliferation PVSMCs, while inhibition of TMEM16A channels inhibited the proliferation of PVSMCs. The results indicated that TMEM16A contributes to PVSMCs proliferation in vitro , but in vivo , it may be a negative regulator of cell proliferation influenced by numerous factors.

  13. Transjugular Intrahepatic Portosystemic Shunt for Portal Hypertension in Hepatocellular Carcinoma with Portal Vein Tumor Thrombus.

    Science.gov (United States)

    Qiu, Bin; Li, Kai; Dong, Xiaoqun; Liu, Fu-Quan

    2017-09-01

    In patients with hepatocellular carcinoma (HCC), limited therapeutic options are available for portal hypertension resulted from portal vein tumor thrombus (PVTT). We aimed to determine safety and efficacy of TIPS for treatment of symptomatic portal hypertension in HCC with PVTT. We evaluated clinical characteristics of 95 patients with HCC and PVTT out of 992 patients who underwent TIPS. The primary endpoints included success rate, procedural mortality, serious complications, decrease in portosystemic pressure gradient, and symptom relief. The secondary endpoints included recurrence of portal hypertension, overall survival, adverse events related to treatments for HCC, and quality of life measured by Karnofsky Performance Status Scale (KPS). Success rate of TIPS was 95.8% (91/95), with procedural mortality of 1.1%. Serious complications related to TIPS procedure occurred in 2.1% (2/95) of patients. The symptoms of portal hypertension were well relieved. Variceal bleeding was successfully controlled and terminated in 100% of patients, with a recurrence rate of 39.2% in 12 months. Refractory ascites/hydrothorax was controlled partially or completely in 92.9% of patients during 1 month after TIPS, with a recurrence rate of 17.9% in 12 months. Survival rate at 6, 12, 24, and 36 months was 75.8, 52.7, 26.4, and 3.3%, respectively. No unexpected adverse event related to treatments for HCC was observed. The KPS score was 49 ± 4.5 and 63 ± 4.7 before and 1 month after TIPS, respectively (p portal hypertension in HCC with PVTT.

  14. A Climate Information Portal for Copernicus: a central portal for European climate services?

    Science.gov (United States)

    Juckes, Martin; Swart, Rob; Thysse, Peter; Som de Cerff, Wim; Groot, Annemarie; Bennett, Victoria; Costa, Luis; Lückenkötter, Johannes; Callaghan, Sarah

    2015-04-01

    The FP7 project "Climate Information Portal for Copernicus" (CLIPC) is developing a demonstration portal for the Copernicus Climate Change Service (C3S). This project is one of a suite of FP7 research activities which are administratively independent of Copernicus, focussed on creating the technical and scientific building blocks needed for the service. It is to be expected that at EGU 2015 there will be many presentations describing portals delivering new and innovative ranges of services. It would be unwise to seek to replace all this creative activity with a single portal -- instead CLIPC is designing a portal to make distributed resources more accessible through flexible discovery systems. CLIPC needs to deliver more than a directory of resources: resources need to be presented in common protocols so that users can access multiple datasets. More information about the project objectives is available at www.clipc.eu. The gulf between the climate science communities and the end user communities is a central challenge being addressed in the project. It is important to understand that there is significant diversity and multiple communication barriers within these two sets of communities as well as between them. The CLIPC services must presentation will provide a review of progress towards this ambitious goal, through a discussion of user requirements activities, an overview of the proposed architecture, work on assessing and adjusting model biasses, and a discussion of the climate impact indicators which will be provided through the portal. When looking at the usability of data for the various users, CLIPC will implement a set of services functioning as a "knowledge base" supplying information to users about the data, including definitions of terminology used, quality of datasets, versioning, and user annotations.

  15. Disastrous Portal Vein Embolization Turned into a Successful Intervention

    Energy Technology Data Exchange (ETDEWEB)

    Dobrocky, Tomas, E-mail: tomas.dobrocky@insel.ch [University of Bern, Department of Interventional, Pediatric and Diagnostic Radiology, Inselspital, University Hospital (Switzerland); Kettenbach, Joachim, E-mail: joachim.kettenbach@stpoelten.lknoe.at [Universitätsklinikum St. Pölten-Lilienfeld, Institute of Medical Radiology, Diagnostic, Intervention (Austria); Lopez-Benitez, Ruben, E-mail: Ruben.lopez@insel.ch; Kara, Levent, E-mail: levent.kara@insel.ch [University of Bern, Department of Interventional, Pediatric and Diagnostic Radiology, Inselspital, University Hospital (Switzerland)

    2015-10-15

    Portal vein embolization (PVE) may be performed before hemihepatectomy to increase the volume of future liver remnant (FLR) and to reduce the risk of postoperative liver insufficiency. We report the case of a 71-year-old patient with hilar cholangiocarcinoma undergoing PVE with access from the right portal vein using a mixture of n-butyl-2-cyanoacrylate and ethiodized oil. During the procedure, nontarget embolization of the left portal vein occurred. An aspiration maneuver of the polymerized plug failed; however, the embolus obstructing portal venous flow in the FLR was successfully relocated into the right portal vein while carefully bypassing the plug with a balloon catheter, inflating the balloon, and pulling the plug into the main right portal vein.

  16. Patient activation and use of an electronic patient portal.

    Science.gov (United States)

    Ancker, Jessica S; Osorio, Snezana N; Cheriff, Adam; Cole, Curtis L; Silver, Michael; Kaushal, Rainu

    2015-01-01

    Electronic patient portals give patients access to personal medical data, potentially creating opportunities to improve knowledge, self-efficacy, and engagement in healthcare. The combination of knowledge, self-efficacy, and engagement has been termed activation. Our objective was to assess the relationship between patient activation and outpatient use of a patient portal. Survey. A telephone survey was conducted with 180 patients who had been given access to a portal, 113 of whom used it and 67 of whom did not. The validated patient activation measure (PAM) was administered along with questions about demographics and behaviors. Portal users were no different from nonusers in patient activation. Portal users did have higher education level and more frequent Internet use, and were more likely to have precisely 2 prescription medications than to have more or fewer. Patients who chose to use an electronic patient portal were not more highly activated than nonusers, although they were more educated and more likely to be Internet users.

  17. Net-erosion profile model and simulation experiments

    International Nuclear Information System (INIS)

    Sagara, Akio

    2001-01-01

    Estimation of net-erosion profile is requisite for evaluating the lifetime of divertor plates under high heat and particle fluxes of fusion plasmas. As a reference in benchmark tests of numerical calculation codes, a self-consistent analytical solution is presented for a simplified divertor condition, wherein the magnetic field line is normal to the target plate and the ionization mean free path of sputtered particles is assumed constant. The primary flux profile of hydrogen and impurities are externally given as well as the return ratio of sputtered atoms to the target. In the direction along the divertor trace, all conditions are uniform. The analytical solution is compared with net-erosion experiments carried out using the Compact Helical System (CHS). The deposition profiles of Ti and O impurities are in very good agreement with the analytical predictions. Recent preliminary results observed on divertor plates in the Large Helical Device (LHD) are briefly presented. (author)

  18. NET remote workstation

    International Nuclear Information System (INIS)

    Leinemann, K.

    1990-10-01

    The goal of this NET study was to define the functionality of a remote handling workstation and its hardware and software architecture. The remote handling workstation has to fulfill two basic functions: (1) to provide the man-machine interface (MMI), that means the interface to the control system of the maintenance equipment and to the working environment (telepresence) and (2) to provide high level (task level) supporting functions (software tools) during the maintenance work and in the preparation phase. Concerning the man-machine interface, an important module of the remote handling workstation besides the standard components of man-machine interfacing is a module for graphical scene presentation supplementing viewing by TV. The technique of integrated viewing is well known from JET BOOM and TARM control using the GBsim and KISMET software. For integration of equipment dependent MMI functions the remote handling workstation provides a special software module interface. Task level support of the operator is based on (1) spatial (geometric/kinematic) models, (2) remote handling procedure models, and (3) functional models of the equipment. These models and the related simulation modules are used for planning, programming, execution monitoring, and training. The workstation provides an intelligent handbook guiding the operator through planned procedures illustrated by animated graphical sequences. For unplanned situations decision aids are available. A central point of the architectural design was to guarantee a high flexibility with respect to hardware and software. Therefore the remote handling workstation is designed as an open system based on widely accepted standards allowing the stepwise integration of the various modules starting with the basic MMI and the spatial simulation as standard components. (orig./HP) [de

  19. The information system Math-Net.Ru. Application of contemporary technologies in the scientific work of mathematicians

    International Nuclear Information System (INIS)

    Zhizhchenko, A B; Izaak, A D

    2007-01-01

    This paper is devoted to a description of the information system Math-Net.Ru, the All-Russian mathematical portal providing various resources to Russian and foreign mathematicians in their search for information for their scientific work (http://www.mathnet.ru/). The most interesting section of the portal is Journals, which combines Russian periodical and continuous publications in the mathematical sciences as a unified information system. The portal structure and its diverse opportunities and tools available for information searches are described. A survey of similar Russian and foreign systems is presented. This article is aimed at the wide community of mathematicians ready to use new information technologies in their research. Technical details of the system's realization are omitted, and attention is focused rather on a description of the users' possibilities.

  20. Portal Still Alive and Portal 2: Lessons from Critical Narrative Gaming Pedagogy

    OpenAIRE

    Yamasaki, Lisa Josefina

    2016-01-01

    Due to the increasing popularity of video games in mass media culture, I will be investigating one particular video game series, Portal: Still Alive and Portal 2, and the manner by which players learn from them. After observing that most instructors use these games in physics and math classes, I want to expand more on the way that video games enact a new story-telling feature through experiential means, which also serves a pedagogical function. I assert that players learn from games through...

  1. Large vehicle portal monitor for perimeter safeguards applications

    International Nuclear Information System (INIS)

    Caldwell, J.T.; Atwater, H.F.; Bernard, W.; Bieri, J.M.; Shunk, E.R.

    1979-01-01

    We have developed a class of vehicle portal monitors based on shielded 4π geometry neutron counting. we have derived and experimentally verified an analytical expression relating the detection sensitivity of the neutron tunnel vehicle portal monitor to four design parameters of the system. For a given number of neutron detectors, this design achieves one or more orders of magnitude improvement in nuclear materials detection sensitivity over previous vehicle portal monitors

  2. Multidetector CT portal venography in evaluation of portosystemic collateral vessels

    International Nuclear Information System (INIS)

    Agarwal, A.; Jain, M.

    2008-01-01

    This essay shows the usefulness of multidetector CT angiography for evaluation of the splenoportal venous system, which is essential in the management of patients with portal hypertension and its complications, such as portal vein thrombosis. By providing scanning with reconstruction of thin axial source images and reformatting into thicker multiplanar reformats, multidetector CT can help to determine the extent and location of portosystemic collateral vessels in patients with portal hypertension and is probably the optimal imaging technique in this setting.

  3. Arachidonic acid metabolites and endothelial dysfunction of portal hypertension.

    Science.gov (United States)

    Sacerdoti, David; Pesce, Paola; Di Pascoli, Marco; Brocco, Silvia; Cecchetto, Lara; Bolognesi, Massimo

    2015-07-01

    Increased resistance to portal flow and increased portal inflow due to mesenteric vasodilatation represent the main factors causing portal hypertension in cirrhosis. Endothelial cell dysfunction, defined as an imbalance between the synthesis, release, and effect of endothelial mediators of vascular tone, inflammation, thrombosis, and angiogenesis, plays a major role in the increase of resistance in portal circulation, in the decrease in the mesenteric one, in the development of collateral circulation. Reduced response to vasodilators in liver sinusoids and increased response in the mesenteric arterioles, and, viceversa, increased response to vasoconstrictors in the portal-sinusoidal circulation and decreased response in the mesenteric arterioles are also relevant to the pathophysiology of portal hypertension. Arachidonic acid (AA) metabolites through the three pathways, cyclooxygenase (COX), lipoxygenase, and cytochrome P450 monooxygenase and epoxygenase, are involved in endothelial dysfunction of portal hypertension. Increased thromboxane-A2 production by liver sinusoidal endothelial cells (LSECs) via increased COX-1 activity/expression, increased leukotriens, increased epoxyeicosatrienoic acids (EETs) (dilators of the peripheral arterial circulation, but vasoconstrictors of the portal-sinusoidal circulation), represent a major component in the increased portal resistance, in the decreased portal response to vasodilators and in the hyper-response to vasoconstrictors. Increased prostacyclin (PGI2) via COX-1 and COX-2 overexpression, and increased EETs/heme-oxygenase-1/K channels/gap junctions (endothelial derived hyperpolarizing factor system) play a major role in mesenteric vasodilatation, hyporeactivity to vasoconstrictors, and hyper-response to vasodilators. EETs, mediators of liver regeneration after hepatectomy and of angiogenesis, may play a role in the development of regenerative nodules and collateral circulation, through stimulation of vascular endothelial

  4. TUX-INTERO: A Portal for secure interoperation of Grids

    OpenAIRE

    Shashi Bhanwar; Seema Bawa

    2010-01-01

    In this paper, we propose TUX-INTERO - a portlet-based Grid portal for integrating existing grid technologies under a common interface and providing reliable services to the users. We have developed a prototype of TUX-INTERO - a grid portal using portlet technology. The paper presents design and development of TUXINTERO. The requirements for the portal, its design and technology choices lead to the utilization of Globus Toolkit as middleware for connecting global resources, SUN N1 GE6 and Con...

  5. Aneurysmal malformation of the extrahepatic portal vein: a case report

    International Nuclear Information System (INIS)

    Lee, Jeong Min; Kang, Sung Soo; Kim, Chong Soo; Han, Hyeun Young

    1999-01-01

    Aneurysmal malformation of the portal vein is a rare entity. To our knowledge, only scattered reports of portal vein aneurysms appear in the literature in English, and there is no previously published report in Korean. We describe a case exhibiting aneurysmal malformation of the extrahepatic portal vein at the hepatic hilum ; the findings demonstrated by ultrasound, CT and angiography are discussed, a review of previously described cases is included

  6. Gamma and neutron detection modeling in the nuclear detection figure of merit (NDFOM) portal

    International Nuclear Information System (INIS)

    Stroud, Phillip D.; Saeger, Kevin J.

    2009-01-01

    The Nuclear Detection Figure Of Merit (NDFOM) portal is a database of objects and algorithms for evaluating the performance of radiation detectors to detect nuclear material. This paper describes the algorithms used to model the physics and mathematics of radiation detection. As a first-principles end-to-end analysis system, it starts with the representation of the gamma and neutron spectral fluxes, which are computed with the particle and radiation transport code MCNPX. The gamma spectra emitted by uranium, plutonium, and several other materials of interest are described. The impact of shielding and other intervening material is computed by the method of build-up factors. The interaction of radiation with the detector material is computed by a detector response function approach. The construction of detector response function matrices based on MCNPX simulation runs is described in detail. Neutron fluxes are represented in a three group formulation to treat differences in detector sensitivities to thermal, epithermal, and fast neutrons.

  7. Interactive web-based portals to improve patient navigation and connect patients with primary care and specialty services in underserved communities.

    Science.gov (United States)

    Highfield, Linda; Ottenweller, Cecelia; Pfanz, Andre; Hanks, Jeanne

    2014-01-01

    This article presents a case study in the redesign, development, and implementation of a web-based healthcare clinic search tool for virtual patient navigation in underserved populations in Texas. It describes the workflow, assessment of system requirements, and design and implementation of two online portals: Project Safety Net and the Breast Health Portal. The primary focus of the study was to demonstrate the use of health information technology for the purpose of bridging the gap between underserved populations and access to healthcare. A combination of interviews and focus groups was used to guide the development process. Interviewees were asked a series of questions about usage, usability, and desired features of the new system. The redeveloped system offers a multitier architecture consisting of data, business, and presentation layers. The technology used in the new portals include Microsoft .NET Framework 3.5, Microsoft SQL Server 2008, Google Maps JavaScript API v3, jQuery, Telerik RadControls (ASP.NET AJAX), and HTML. The redesigned portals have 548 registered clinics, and they have averaged 355 visits per month since their launch in late 2011, with the average user visiting five pages per visit. Usage has remained relatively constant over time, with an average of 142 new users (40 percent) each month. This study demonstrates the successful application of health information technology to improve access to healthcare and the successful adoption of the technology by targeted end users. The portals described in this study could be replicated by health information specialists in other areas of the United States to address disparities in healthcare access.

  8. Congenital absence of the portal vein presenting as pulmonary hypertension

    International Nuclear Information System (INIS)

    Jun, Sur Young; Lee, Whal; Cheon, Jung Eun; Kim, Woo Sun; Kim, In One; Yeon, Kyung Mo

    2007-01-01

    Congenital absence of the portal vein (CAPV) is a rare malformation in which intestinal and splenic venous flow bypasses the liver and drains directly into the systemic circulation via a congenital portosystemic shunt. We describe two cases of CAPV presenting as pulmonary hypertension that were initially suspected as primary pulmonary hypertension. However, subsequent ultrasonography and CT detected the absence of a portal vein and the presence of a portosystemic shunt. Pulmonary hypertension is a recognized complication of liver disease and portal hypertension. However, these two cases illustrate that CAPV may result in pulmonary hypertension without liver disease or portal hypertension

  9. Indications for portal pressure measurement in chronic liver disease

    DEFF Research Database (Denmark)

    Hobolth, Lise; Bendtsen, Flemming; Møller, Søren

    2012-01-01

    Portal hypertension leads to development of serious complications such as esophageal varices, ascites, renal and cardiovascular dysfunction. The importance of the degree of portal hypertension has been substantiated within recent years. Measurement of the portal pressure is simple and safe...... and the hepatic venous pressure gradient (HVPG) independently predicts survival and development of complications such as ascites, HCC and bleeding from esophageal varices. Moreover, measurements of HVPG can be used to guide pharmacotherapy for primary and secondary prophylaxis for variceal bleeding. Assessment...... of HVPG should therefore be considered as a part of the general characterization of patients with portal hypertension in departments assessing and treating this condition....

  10. Congenital absence of the portal vein presenting as pulmonary hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Sur Young; Lee, Whal; Cheon, Jung Eun; Kim, Woo Sun; Kim, In One; Yeon, Kyung Mo [Seoul National University Hospital, Seoul (Korea, Republic of)

    2007-11-15

    Congenital absence of the portal vein (CAPV) is a rare malformation in which intestinal and splenic venous flow bypasses the liver and drains directly into the systemic circulation via a congenital portosystemic shunt. We describe two cases of CAPV presenting as pulmonary hypertension that were initially suspected as primary pulmonary hypertension. However, subsequent ultrasonography and CT detected the absence of a portal vein and the presence of a portosystemic shunt. Pulmonary hypertension is a recognized complication of liver disease and portal hypertension. However, these two cases illustrate that CAPV may result in pulmonary hypertension without liver disease or portal hypertension.

  11. Vertical divergence of fogwater fluxes above a spruce forest

    Science.gov (United States)

    Burkard, R.; Eugster, W.; Wrzesinsky, T.; Klemm, O.

    Two almost identical eddy covariance measurement setups were used to measure the fogwater fluxes to a forest ecosystem in the "Fichtelgebirge" mountains (Waldstein research site, 786 m a.s.l.) in Germany. During the first experiment, an intercomparison was carried out with both setups running simultaneously at the same measuring height on a meteorological tower, 12.5 m above the forest canopy. The results confirmed a close agreement of the turbulent fluxes between the two setups, and allowed to intercalibrate liquid water content (LWC) and gravitational fluxes. During the second experiment, the setups were mounted at a height of 12.5 and 3 m above the canopy, respectively. For the 22 fog events, a persistent negative flux divergence was observed with a greater downward flux at the upper level. To extrapolate the turbulent liquid water fluxes measured at height z to the canopy of height hc, a conversion factor 1/[1+0.116( z- hc)] was determined. For the fluxes of nonvolatile ions, no such correction is necessary since the net evaporation of the fog droplets appears to be the primary cause of the vertical flux divergence. Although the net evaporation reduces the liquid water flux reaching the canopy, it is not expected to change the absolute amount of ions dissolved in fogwater.

  12. Conformal Nets II: Conformal Blocks

    Science.gov (United States)

    Bartels, Arthur; Douglas, Christopher L.; Henriques, André

    2017-08-01

    Conformal nets provide a mathematical formalism for conformal field theory. Associated to a conformal net with finite index, we give a construction of the `bundle of conformal blocks', a representation of the mapping class groupoid of closed topological surfaces into the category of finite-dimensional projective Hilbert spaces. We also construct infinite-dimensional spaces of conformal blocks for topological surfaces with smooth boundary. We prove that the conformal blocks satisfy a factorization formula for gluing surfaces along circles, and an analogous formula for gluing surfaces along intervals. We use this interval factorization property to give a new proof of the modularity of the category of representations of a conformal net.

  13. Pro asynchronous programming with .NET

    CERN Document Server

    Blewett, Richard; Ltd, Rock Solid Knowledge

    2014-01-01

    Pro Asynchronous Programming with .NET teaches the essential skill of asynchronous programming in .NET. It answers critical questions in .NET application development, such as: how do I keep my program responding at all times to keep my users happy how do I make the most of the available hardware how can I improve performanceIn the modern world, users expect more and more from their applications and devices, and multi-core hardware has the potential to provide it. But it takes carefully crafted code to turn that potential into responsive, scalable applications.With Pro Asynchronous Programming

  14. Area-averaged surface fluxes and their time-space variability over the FIFE experimental domain

    Science.gov (United States)

    Smith, E. A.; Hsu, A. Y.; Crosson, W. L.; Field, R. T.; Fritschen, L. J.; Gurney, R. J.; Kanemasu, E. T.; Kustas, W. P.; Nie, D.; Shuttleworth, W. J.

    1992-01-01

    The underlying mean and variance properties of surface net radiation, sensible-latent heat fluxes and soil heat flux are studied over the densely instrumented grassland region encompassing FIFE. Flux variability is discussed together with the problem of scaling up to area-averaged fluxes. Results are compared and contrasted for cloudy and clear situations and examined for the influence of surface-induced biophysical controls (burn and grazing treatments) and topographic controls (aspect ratios and slope factors).

  15. The influence of culture on enterprise portal design in a global environment

    NARCIS (Netherlands)

    Feng, Xiuzhen; Ehrenhard, Michel Léon; Hicks, Jeff; Hou, Yibin; Khosrow-Pour, M.

    2007-01-01

    Enterprise portals collect and synthesize information from various systems to deliver personalized and highly relevant information to suppliers, customers and employees. While enterprise portal design and portal applications have been widely discussed in the literature, the implications that arise

  16. Portal vein stenting for delayed jejunal varix bleeding associated with portal venous occlusion after hepatoiliary and pancreatic surgery

    Energy Technology Data Exchange (ETDEWEB)

    Hyun, Dong Ho; Park, Kwang Bo; Cho, Sung Ki; Park, Hong Suk; Shin, Sung Wook; Choo, Sung Wook; Do, Young Soo; Choo, In Wook; Choi, Dong Wook [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2017-09-15

    The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop. Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method. All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred. Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery.

  17. Portal vein stenting for delayed jejunal varix bleeding associated with portal venous occlusion after hepatoiliary and pancreatic surgery

    International Nuclear Information System (INIS)

    Hyun, Dong Ho; Park, Kwang Bo; Cho, Sung Ki; Park, Hong Suk; Shin, Sung Wook; Choo, Sung Wook; Do, Young Soo; Choo, In Wook; Choi, Dong Wook

    2017-01-01

    The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop. Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method. All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred. Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery

  18. A novel canine model of portal vein stenosis plus thioacetamide administration-induced cirrhotic portal hypertension with hypersplenism.

    Science.gov (United States)

    Lin, Dexin; Wu, Xianbin; Ji, Xiaoke; Zhang, Qiyu; Lin, YuanWei; Chen, WeiJian; Jin, Wangxun; Deng, Liming; Chen, Yunzhi; Chen, Bicheng; Li, Jianmin

    2012-01-01

    Current large animal models that could closely resemble the typical features of cirrhotic portal hypertension in human have not been well established. Thus, we aimed to develop and describe a reliable and reproducible canine cirrhosis model of portal hypertension. A total of 30 mongrel dogs were randomly divided into four groups: 1 (control; n = 5), 2 (portal vein stenosis [PVS]; n = 5], 3 (thioacetamide [TAA]; n = 5), and 4 (PVS plus TAA; n = 15). After 4-months modeling period, liver and spleen CT perfusion, abdominal CT scans, portal hemodynamics, gastroscopy, hepatic function, blood routine, the bone marrow, liver, and spleen histology were studied. The animals in group 2 (PVS) developed extrahepatic portosystemic collateral circulation, particularly esophageal varices, without hepatic cirrhosis and portal hypertension. Animals from group 3 (TAA) presented mild cirrhosis and portal hypertension without significant symptoms of esophageal varices and hypersplenism. In contrast, animals from group 4 (PVS + TAA) showed well-developed micronodular and macronodular cirrhosis, associated with significant portal hypertension and hypersplenism. The combination of PVS and TAA represents a novel, reliable, and reproducible canine cirrhosis model of portal hypertension, which is associated with the typical characteristics of portal hypertension, including hypersplenism.

  19. [11C]palmitate kinetics across the splanchnic bed in arterial, portal and hepatic venous plasma during fasting and euglycemic hyperinsulinemia

    International Nuclear Information System (INIS)

    Guiducci, Letizia; Jaervisalo, Mikko; Kiss, Jan; Nagren, Kjell; Viljanen, Antti; Naum, Alexandru G.; Gastaldelli, Amalia; Savunen, Timo; Knuuti, Juhani; Salvadori, Piero A.; Ferrannini, Ele; Nuutila, Pirjo; Iozzo, Patricia

    2006-01-01

    Purpose: The liver is fundamental in regulating lipid metabolism, and it supplies fatty acids (FA) to the rest of the body in the form of triglycerides (TG); the time-related relevance of this process is incompletely defined. The aim of the study was to investigate the appearance of labeled TG in the hepatic vascular bed after [ 11 C]palmitate injection during fasting and insulin stimulation. Methods: Plasma [ 11 C]palmitate kinetics in arterial, portal and hepatic venous lipid fractions was studied in eight anesthetized pigs during fasting or euglycemic hyperinsulinemia. Plasma analyses were conducted at 10 and 40 min after tracer injection. Corresponding liver positron emission tomography (PET) images were acquired for the semiquantitative determination of hepatic FA uptake. Results: At 10 min, plasma levels of unchanged [ 11 C]palmitate were lower in hyperinsulinemic than in fasting experiments in the artery and in the portal vein (P≤.03), suggesting faster clearance. Levels of unmetabolized [ 11 C]palmitate did not differ between portal and arterial plasma. In the fasting state, a tendency to a positive arterial and portal vs. hepatic venous gradient was observed, indicative of net hepatic [ 11 C]palmitate extraction. Labeled TG were already detectable at 10 min (fasting vs. hyperinsulinemia, ns) and were higher in fasting than in hyperinsulinemic animals at 40 min (92±1% and 82±6% of arterial plasma radioactivity). Higher proportions of labeled TG were recovered in portal vein plasma, suggesting release by the gut. The portal and the arterial-portal vs. hepatic venous TG gradient tended to be positive. Accordingly, hepatic FA uptake was higher, but declined more rapidly during fasting than during hyperinsulinemia. Conclusion: The study indicates that the redistribution of [ 11 C]palmitate between different lipid pools occurs within the short time interval of most PET experiments and is strongly influenced by insulin. Labeled TG constitute an additional

  20. [{sup 11}C]palmitate kinetics across the splanchnic bed in arterial, portal and hepatic venous plasma during fasting and euglycemic hyperinsulinemia

    Energy Technology Data Exchange (ETDEWEB)

    Guiducci, Letizia [SSSUP Medical Sciences Branch, Pisa 56100 (Italy); Turku PET Centre, University of Turku, Turku 20520 (Finland); PET Centre, Institute of Clinical Physiology, CNR National Research Council, 56100 Pisa (Italy); Jaervisalo, Mikko [Turku PET Centre, University of Turku, Turku 20520 (Finland); Kiss, Jan [Turku PET Centre, University of Turku, Turku 20520 (Finland); Department of Surgery, University of Turku, Turku 20520 (Finland); Nagren, Kjell [Turku PET Centre, University of Turku, Turku 20520 (Finland); Viljanen, Antti [Turku PET Centre, University of Turku, Turku 20520 (Finland); Naum, Alexandru G. [Turku PET Centre, University of Turku, Turku 20520 (Finland); Gastaldelli, Amalia [PET Centre, Institute of Clinical Physiology, CNR National Research Council, 56100 Pisa (Italy); Savunen, Timo [Department of Surgery, University of Turku, Turku 20520 (Finland); Knuuti, Juhani [Turku PET Centre, University of Turku, Turku 20520 (Finland); Salvadori, Piero A. [PET Centre, Institute of Clinical Physiology, CNR National Research Council, 56100 Pisa (Italy); Ferrannini, Ele [PET Centre, Institute of Clinical Physiology, CNR National Research Council, 56100 Pisa (Italy); Department of Internal Medicine, University of Pisa School of Medicine, Pisa 56100 (Italy); Nuutila, Pirjo [Turku PET Centre, University of Turku, Turku 20520 (Finland); Department of Medicine, University of Turku, Turku 20520 (Finland); Iozzo, Patricia [Turku PET Centre, University of Turku, Turku 20520 (Finland) and PET Centre, Institute of Clinical Physiology, CNR National Research Council, 56100 Pisa (Italy)]. E-mail: patricia.iozzo@ifc.cnr.it

    2006-05-15

    Purpose: The liver is fundamental in regulating lipid metabolism, and it supplies fatty acids (FA) to the rest of the body in the form of triglycerides (TG); the time-related relevance of this process is incompletely defined. The aim of the study was to investigate the appearance of labeled TG in the hepatic vascular bed after [{sup 11}C]palmitate injection during fasting and insulin stimulation. Methods: Plasma [{sup 11}C]palmitate kinetics in arterial, portal and hepatic venous lipid fractions was studied in eight anesthetized pigs during fasting or euglycemic hyperinsulinemia. Plasma analyses were conducted at 10 and 40 min after tracer injection. Corresponding liver positron emission tomography (PET) images were acquired for the semiquantitative determination of hepatic FA uptake. Results: At 10 min, plasma levels of unchanged [{sup 11}C]palmitate were lower in hyperinsulinemic than in fasting experiments in the artery and in the portal vein (P{<=}.03), suggesting faster clearance. Levels of unmetabolized [{sup 11}C]palmitate did not differ between portal and arterial plasma. In the fasting state, a tendency to a positive arterial and portal vs. hepatic venous gradient was observed, indicative of net hepatic [{sup 11}C]palmitate extraction. Labeled TG were already detectable at 10 min (fasting vs. hyperinsulinemia, ns) and were higher in fasting than in hyperinsulinemic animals at 40 min (92{+-}1% and 82{+-}6% of arterial plasma radioactivity). Higher proportions of labeled TG were recovered in portal vein plasma, suggesting release by the gut. The portal and the arterial-portal vs. hepatic venous TG gradient tended to be positive. Accordingly, hepatic FA uptake was higher, but declined more rapidly during fasting than during hyperinsulinemia. Conclusion: The study indicates that the redistribution of [{sup 11}C]palmitate between different lipid pools occurs within the short time interval of most PET experiments and is strongly influenced by insulin. Labeled TG

  1. Novel Rat Model of Repetitive Portal Venous Embolization Mimicking Human Non-Cirrhotic Idiopathic Portal Hypertension.

    Science.gov (United States)

    Klein, Sabine; Hinüber, Christian; Hittatiya, Kanishka; Schierwagen, Robert; Uschner, Frank Erhard; Strassburg, Christian P; Fischer, Hans-Peter; Spengler, Ulrich; Trebicka, Jonel

    2016-01-01

    Non-cirrhotic idiopathic portal hypertension (NCIPH) is characterized by splenomegaly, anemia and portal hypertension, while liver function is preserved. However, no animal models have been established yet. This study assessed a rat model of NCIPH and characterized the hemodynamics, and compared it to human NCIPH. Portal pressure (PP) was measured invasively and coloured microspheres were injected in the ileocecal vein in rats. This procedure was performed weekly for 3 weeks (weekly embolization). Rats without and with single embolization served as controls. After four weeks (one week after last embolization), hemodynamics were investigated, hepatic fibrosis and accumulation of myofibroblasts were analysed. General characteristics, laboratory analyses and liver histology were collected in patients with NCIPH. Weekly embolization induced a hyperdynamic circulation, with increased PP. The mesenteric flow and hepatic hydroxyproline content was significantly higher in weekly embolized compared to single embolized rats (mesenteric flow +54.1%, hydroxyproline +41.7%). Mesenteric blood flow and shunt volumes increased, whereas splanchnic vascular resistance was decreased in the weekly embolization group. Fibrotic markers αSMA and Desmin were upregulated in weekly embolized rats. This study establishes a model using repetitive embolization via portal veins, comparable with human NCIPH and may serve to test new therapies.

  2. Fundamental factors influencing portal image quality

    International Nuclear Information System (INIS)

    Jaffray, D.A.

    1995-01-01

    It has been recognized that improved methods of verifying radiation field placement in external beam radiotherapy are required in order to make frequent checks of field placement feasible. As a result, a large number of electronic portal imaging systems have been developed as possible replacements for film. These developments have produced digital systems with faster acquisition and improved display contrast, however, the quality of the images acquired with such systems is still disappointing. This presentation examines many of the fundamental factors which limit the quality of radiographs obtained with a megavoltage radiotherapy beam. The size and shape of the radiation sources (focal and extra-focal) in radiotherapy machines and their influence on the spatial resolution of portal images are examined. Monte Carlo simulations of x-ray interactions within the patient determined that a significant fraction of the x-ray scatter generated in the patient is due to bremsstrahlung and positron annihilation. Depending on the detector, the scatter signal can reduce the differential signal-to-noise by 20%. Furthermore, a Monte Carlo study of the interaction of x-rays within typical fluoroscopic imaging detectors (metal plate/phosphor screen) demonstrates the degrading effect of energy absorption noise on the detective quantum efficiency of fluoroscopic based imaging systems. Finally, the spatial frequency content in the x-ray shadowgram is demonstrated to change with x-ray energy, resulting in images that appear to have reduced spatial resolution at megavoltage energies. The relative magnitude of each of these factors will be presented and recommendations for the next generation of portal imaging systems will be made

  3. An automated portal verification system for the tangential breast portal field

    International Nuclear Information System (INIS)

    Yin, F.-F.; Lai, W.; Chen, C. W.; Nelson, D. F.

    1995-01-01

    Purpose/Objective: In order to ensure the treatment is delivered as planned, a portal image is acquired in the accelerator and is compared to the reference image. At present, this comparison is performed by radiation oncologists based on the manually-identified features, which is both time-consuming and potentially error-prone. With the introduction of various electronic portal imaging devices, real-time patient positioning correction is becoming clinically feasible to replace time-delayed analysis using films. However, this procedure requires present of radiation oncologists during patient treatment which is not cost-effective and practically not realistic. Therefore, the efficiency and quality of radiation therapy could be substantially improved if this procedure can be automated. The purpose of this study is to develop a fully computerized verification system for the radiation therapy of breast cancer for which a similar treatment setup is generally employed. Materials/Methods: The automated verification system involves image acquisition, image feature extraction, feature correlation between reference and portal images, and quantitative evaluation of patient setup. In this study, a matrix liquid ion-chamber EPID was used to acquire digital portal images which is directly attached to Varian CL2100C accelerator. For effective use of computation memory, the 12-bit gray levels in original portal images were quantized to form a range of 8-bit gray levels. A typical breast portal image includes three important components: breast and lung tissues in the treatment field, air space within the treatment field, and non-irradiated region. A hierarchical region processing technique was developed to separate these regions sequentially. The inherent hierarchical features were formulated based on different radiation attenuation for different regions as: treatment field edge -- breast skin line -- chest wall. Initially, a combination of a Canny edge detector and a constrained

  4. Total hepatofugal portal blood flow in cirrhosis demonstrated by transhepatic portography

    International Nuclear Information System (INIS)

    Burcharth, F.; Aagaard, J.; Herlev Hospital

    1988-01-01

    We investigated 108 patients with cirrhosis of the liver and portal hypertension by percutaneous transhepatic portography to demonstrate the occurrence and frequency of total hepatofugal portal blood flow. Sixteen patients (14.8%) had a total hepatofugal portal blood flow. The aetiology of portal hypertension and the portal pressure did not differ from that in the group of patients with hepatopetal portal blood flow. A significantly higher percentage of patients in the group with hepatofugal flow had gastro-oesophageal varices (P [de

  5. KM3NeT

    CERN Multimedia

    KM3NeT is a large scale next-generation neutrino telescope located in the deep waters of the Mediterranean Sea, optimized for the discovery of galactic neutrino sources emitting in the TeV energy region.

  6. Pickering nuclear fish diversion net

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, J.; Lew, A. [Ontario Power Generation, Toronto, Ontario (Canada)

    2013-07-01

    Pickering Fish Diversion Net - An Engineered Environmental Solution that has significantly reduced fish impingement at the Pickering Nuclear Facility. Note: As a recent urgent request/discussed by Mark Elliot, CNE-OPG and Jacques Plourde, CNS.

  7. PolicyNet Publication System

    Data.gov (United States)

    Social Security Administration — The PolicyNet Publication System project will merge the Oracle-based Policy Repository (POMS) and the SQL-Server CAMP system (MSOM) into a new system with an Oracle...

  8. Net Neutrality: Background and Issues

    National Research Council Canada - National Science Library

    Gilroy, Angele A

    2006-01-01

    .... The move to place restrictions on the owners of the networks that compose and provide access to the Internet, to ensure equal access and nondiscriminatory treatment, is referred to as "net neutrality...

  9. EUFAR the unique portal for airborne research in Europe

    Science.gov (United States)

    Gérard, Elisabeth; Brown, Philip

    2016-04-01

    Created in 2000 and supported by the EU Framework Programmes since then, EUFAR was born out of the necessity to create a central network and access point for the airborne research community in Europe. With the aim to support researchers by granting them access to research infrastructures, not accessible in their home countries, EUFAR also provides technical support and training in the field of airborne research for the environmental and geo-sciences. Today, EUFAR2 (2014-2018) coordinates and facilitates transnational access to 18 instrumented aircraft and 3 remote-sensing instruments through the 13 operators who are part of EUFAR's current 24-partner European consortium. In addition, the current project supports networking and research activities focused on providing an enabling environment for and promoting airborne research. The EUFAR2 activities cover three objectives, supported by the internet website www.eufar.net: (I - Institutional) improvement of the access to the research infrastructures and development of the future fleet according to the strategic advisory committee (SAC) recommendations; (ii - Innovation) improvement of the scientific knowledge and promotion of innovating instruments, processes and services for the emergence of new industrial technologies, with an identification of industrial needs by the SAC; (iii - Service) optimisation and harmonisation of the use of the research infrastructures through the development of the community of young researches in airborne science, of the standards and protocols and of the airborne central database. With the launch of a brand new website (www.eufar.net) in mid-November 2015, EUFAR aims to improve user experience on the website, which serves as a source of information and a hub where users are able to collaborate, learn, share expertise and best practices, and apply for transnational access, and education and training funded opportunities within the network. With its newly designed eye-catching interface

  10. Analisis Determinan Net Ekspor Indonesia

    OpenAIRE

    Daulay, Rahmawaty

    2010-01-01

    This study is to analyzing empirically among Indonesia GDP, trade partnership GDP (Malaysia, Singapore, US and Thailand) and real exchange rate toward Indonesia Net Export. To find out which one from those three variables is significant in order to fluctuating (increasing or decreasing) Indonesia Net Export either in the short run or in the long run. Data collection is obtained using secondary data, namely Indonesia GDP, Malaysia GDP, Singapura GDP, US GDP, Thailand GDP and real exchange rate...

  11. NetBeans GUI Builder

    OpenAIRE

    Pusiankova, Tatsiana

    2009-01-01

    This work aims at making readers familiar with the powerful tool NetBeans IDE GUI Builder and helping them make their first steps to creation of their own graphical user interface in the Java programming language. The work includes theoretical description of NetBeans IDE GUI Builder, its most important characteristics and peculiarities and also a set of practical instructions that will help readers in creation of their first GUI. The readers will be introduced to the environment of this tool ...

  12. Developing the architecture for the Climate Information Portal for Copernicus

    Science.gov (United States)

    Som de Cerff, Wim; Thijsse, Peter; Plieger, Maarten; Pascoe, Stephen; Jukes, Martin; Leadbetter, Adam; Goosen, Hasse; de Vreede, Ernst

    2015-04-01

    environment and society, but will develop an end to end processing chain (indicator toolkit), from comprehensive information on the climate state through to highly aggregated decision relevant products. This processing chain will be demonstrated within three thematic areas: water, rural and urban. Indicators of climate change and climate change impact will be provided, and a toolkit to update and post process the collection of indicators will be integrated into the portal. For the indicators three levels (Tiers) have been loosely defined: Tier 1: field summarising properties of the climate system; e.g. temperature change; Tier 2: expressed in terms of environmental properties outside the climate system; e.g. flooding change; Tier 3: expressed in social and economic impact. For the architecture, CLIPC has two interlocked themes: 1. Harmonised access to climate datasets derived from models, observations and re-analyses 2. A climate impact toolkit to evaluate, rank and aggregate indicators For development of the CLIPC architecture an Agile 'storyline' approach is taken. The storyline is a real world use case and consists of producing a Tier 3 indicator (Urban Heat Vulnerability) and making it available through the CLIPC infrastructure for a user group. In this way architecture concepts can be directly tested and improved. Also, the produced indicator can be shown to users to refine requirements. Main components of the CLIPC architecture are 1) Data discovery and access, 2) Data processing, 3) Data visualization, 4) Knowledge base and 5) User Management. The Data discovery and access component main challenge is to provide harmonized access to various sources of climate data (ngEO, EMODNET/SeaDataNet, ESGF, MyOcean). The discovery service concept will be provided using a CLIPC data and data product catalogue and via a structured data search on selected infrastructures, using NERC vocabulary services and mappings. Data processing will be provided using OGC WPS services, linking

  13. Incoming Shortwave Fluxes at the Surface--A Comparison of GCM Results with Observations.

    Science.gov (United States)

    Garratt, J. R.

    1994-01-01

    Evidence is presented that the exam surface net radiation calculated in general circulation models at continental surfaces is mostly due to excess incoming shortwave fluxes. Based on long-term observations from 22 worldwide inland stations and results from four general circulation models the overestimate in models of 20% (11 W m2) in net radiation on an annual basis compares with 6% (9 W m2) for shortwave fluxes for the same 22 locations, or 9% (18 W m2) for a larger set of 93 stations (71 having shortwave fluxes only). For annual fluxes, these differences appear to be significant.

  14. Multiflavor string-net models

    Science.gov (United States)

    Lin, Chien-Hung

    2017-05-01

    We generalize the string-net construction to multiple flavors of strings, each of which is labeled by the elements of an Abelian group Gi. The same flavor of strings can branch, while different flavors of strings can cross one another and thus they form intersecting string nets. We systematically construct the exactly soluble lattice Hamiltonians and the ground-state wave functions for the intersecting string-net condensed phases. We analyze the braiding statistics of the low-energy quasiparticle excitations and find that our model can realize all the topological phases as the string-net model with group G =∏iGi . In this respect, our construction provides various ways of building lattice models which realize topological order G , corresponding to different partitions of G and thus different flavors of string nets. In fact, our construction concretely demonstrates the Künneth formula by constructing various lattice models with the same topological order. As an example, we construct the G =Z2×Z2×Z2 string-net model which realizes a non-Abelian topological phase by properly intersecting three copies of toric codes.

  15. Clustering of Emerging Flux

    Science.gov (United States)

    Ruzmaikin, A.

    1997-01-01

    Observations show that newly emerging flux tends to appear on the Solar surface at sites where there is flux already. This results in clustering of solar activity. Standard dynamo theories do not predict this effect.

  16. Endovascular management for significant iatrogenic portal vein bleeding.

    Science.gov (United States)

    Kim, Jong Woo; Shin, Ji Hoon; Park, Jonathan K; Yoon, Hyun-Ki; Ko, Gi-Young; Gwon, Dong Il; Kim, Jin Hyoung; Sung, Kyu-Bo

    2017-11-01

    Background Despite conservative treatment, hemorrhage from an intrahepatic branch of the portal vein can cause hemodynamic instability requiring urgent intervention. Purpose To retrospectively report the outcomes of hemodynamically significant portal vein bleeding after endovascular management. Material and Methods During a period of 15 years, four patients (2 men, 2 women; median age, 70.5 years) underwent angiography and embolization for iatrogenic portal vein bleeding. Causes of hemorrhage, angiographic findings, endovascular treatment, and complications were reported. Results Portal vein bleeding occurred after percutaneous liver biopsy (n = 2), percutaneous radiofrequency ablation (n = 1), and percutaneous cholecystostomy (n = 1). The median time interval between angiography and percutaneous procedure was 5 h (range, 4-240 h). Common hepatic angiograms including indirect mesenteric portograms showed active portal vein bleeding into the peritoneal cavity with (n = 1) or without (n = 2) an arterioportal (AP) fistula, and portal vein pseudoaneurysm alone with an AP fistula (n = 1). Successful transcatheter arterial embolization (n = 2) or percutaneous transhepatic portal vein embolization (n = 2) was performed. Embolic materials were n-butyl cyanoacrylate alone (n = 2) or in combination with gelatin sponge particles and coils (n = 2). There were no major treatment-related complications or patient mortality within 30 days. Conclusion Patients with symptomatic or life-threatening portal vein bleeding following liver-penetrating procedures can successfully be managed with embolization.

  17. Idiopathic non-cirrhotic portal hypertension: a review

    NARCIS (Netherlands)

    Schouten, Jeoffrey N. L.; Verheij, Joanne; Seijo, Susana

    2015-01-01

    Idiopathic non-cirrhotic portal hypertension (INCPH) is a rare disease characterized of intrahepatic portal hypertension in the absence of cirrhosis or other causes of liver disease and splanchnic venous thrombosis. The etiology of INCPH can be classified in five categories: 1) immunological

  18. Transhepatic course of the portal vein with subcapsular ramification

    Energy Technology Data Exchange (ETDEWEB)

    Goebel, N

    1985-06-01

    In a patient, investigated for uterine carcinoma, CT of the liver showed an anomalous course of a large portal vein, which traversed the liver and divided under the ventrolateral liver capsule in its branches. There were no signs of portal hypertension.

  19. Pathology of idiopathic non-cirrhotic portal hypertension.

    Science.gov (United States)

    Guido, Maria; Sarcognato, Samantha; Sacchi, Diana; Colloredo, Guido

    2018-04-12

    Idiopathic non-cirrhotic portal hypertension is an under-recognized vascular liver disease of unknown etiology, characterized by clinical signs of portal hypertension in the absence of cirrhosis. By definition, any disorder known to cause portal hypertension in the absence of cirrhosis and any cause of chronic liver disease must be excluded to make a diagnosis of idiopathic non-cirrhotic portal hypertension. However, the diagnosis is often difficult because the disease resembles cirrhosis and there is no gold standard test. Liver biopsy is an essential tool: it is able to exclude cirrhosis and other causes of portal hypertension and it allows the identification of the characteristic lesions. Nonetheless, the histological diagnosis of idiopathic non-cirrhotic portal hypertension is not always straightforward, in particular by needle biopsy samples, because there is no pathognomonic lesion, but rather a variety of vascular changes which are unevenly distributed, very subtle, and not all necessarily identified in a single specimen. Pathologists should be able to recognize several patterns of injury, involving portal/periportal areas as well as parenchymal structures.The histological features of idiopathic non-cirrhotic portal hypertension are described in this review, focusing on their interpretation in needle biopsy specimens.

  20. Tracks: The New York City Rat Information Portal

    Centers for Disease Control (CDC) Podcasts

    This podcast, featuring Daniel Kass, Acting Deputy Commissioner of Environmental Health for the New York City (NYC) Department of Health and Mental Hygiene, provides information about the NYC Rat Information Portal. It details the background and uses of the Rat Portal, as well as next steps for the NYC Environmental Public Health Tracking Program.

  1. Intrahepatic portal hypertension secondary to metastatic carcinoma of the prostate.

    Science.gov (United States)

    Attila, Tan; Datta, Milton W; Sudakoff, Gary; Abu-Hajir, Majed; Massey, Benson T

    2007-02-01

    While the liver is a common site of metastasis, tumor metastases are not a common cause of portal hypertension. We report a case of a patient with symptomatic portal hypertension due to diffuse metastatic prostate carcinoma infiltration of liver parenchyma that was not appreciated with routine imaging.

  2. Improving image quality in portal venography with spectral CT imaging

    International Nuclear Information System (INIS)

    Zhao, Li-qin; He, Wen; Li, Jian-ying; Chen, Jiang-hong; Wang, Ke-yang; Tan, Li

    2012-01-01

    Objective: To investigate the effect of energy spectral CT on the image quality of CT portal venography in cirrhosis patients. Materials and methods: 30 portal hypertension patients underwent spectral CT examination using a single-tube, fast dual tube voltage switching technique. 101 sets of monochromatic images were generated from 40 keV to 140 keV. Image noise and contrast-to-noise ratio (CNR) for portal veins from the monochromatic images were measured. An optimal monochromatic image set was selected for obtaining the best CNR for portal veins. The image noise and CNR of the intra-hepatic portal vein and extra-hepatic main stem at the selected monochromatic level were compared with those from the conventional polychromatic images. Image quality was also assessed and compared. Results: The monochromatic images at 51 keV were found to provide the best CNR for both the intra-hepatic and extra-hepatic portal veins. At this energy level, the monochromatic images had about 100% higher CNR than the polychromatic images with a moderate 30% noise increase. The qualitative image quality assessment was also statistically higher with monochromatic images at 51 keV. Conclusion: Monochromatic images at 51 keV for CT portal venography could improve CNR for displaying hepatic portal veins and improve the overall image quality.

  3. Meaningful Use of a Confidential Adolescent Patient Portal.

    Science.gov (United States)

    Thompson, Lindsay A; Martinko, Thomas; Budd, Pamela; Mercado, Rebeccah; Schentrup, Anzeela M

    2016-02-01

    To design and evaluate the usage of an adolescent patient portal specifically adapted for adolescent health care needs that also satisfied institutional meaningful use guidelines regarding electronic health records. Key stakeholders at one academic health care center adopted an online portal and opted to designate a patient portal specifically for adolescents to maximize confidentiality in compliance with state privacy laws. This study analyzed aggregate electronic health record data of adolescents' (ages 12-17.9 years) uptake, usage, and functionality of this portal and compared it to parent portal usage for younger children (ages 0-11 years). Differences in means were calculated using paired t tests. The portal was used similarly between parents of young children and adolescents, with almost 1,000 enrollees in each group from September 1, 2012 to March 31, 2015. There were no gender differences in enrollment. Adolescents were less likely than parents of younger children to review appointments (73% vs. 85%), laboratory tests (67% vs. 79%), problem lists (40% vs. 78%), or allergies (45% vs. 77%, all p values adolescents sent 1,397 confidential messages. Institutional decisions for implementing meaningful use requirements can align with goals of adolescent health. Patient portals can enhance adolescent health care quality and adolescents readily use a confidential portal. Implementation of meaningful use requirements should be checked against adolescent health care needs to maximize confidentiality and promote health communication. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  4. Continued Use of a Chinese Online Portal: An Empirical Study

    Science.gov (United States)

    Shih, Hung-Pin

    2008-01-01

    The evolution of the internet has made online portals a popular means of surfing the internet. In internet commerce, understanding the post-adoption behaviour of users of online portals can help enterprises to attract new users and retain existing customers. For predicting continued use intentions, this empirical study focused on applying and…

  5. An Analysis of Knowledge Management Mechanisms in Healthcare Portals

    Science.gov (United States)

    Lee, Chei Sian; Goh, Dion Hoe-Lian; Chua, Alton Y. K.

    2010-01-01

    Healthcare portals are becoming increasingly popular with Internet users since they play an important role in supporting interaction between individuals and healthcare organizations with a Web presence. Additionally, many of these organizations make use of knowledge management mechanisms on their healthcare portals to manage the abundance of…

  6. Measuring Campus Portal Effectiveness and the Contributing Factors

    Science.gov (United States)

    Masrek, Mohamad Noorman bin

    2007-01-01

    Purpose: The purpose of the paper is to evaluate the effectiveness or success of universities' portal implementation from the perspective of students as users. Adopting the model developed by Delone and McLean, portal effectiveness is defined as being composed of information quality, systems quality and service quality. In addition, the paper also…

  7. Enviroportal.sk - information portal about the environment

    International Nuclear Information System (INIS)

    Navratil, R.; Kmet, M.

    2005-01-01

    In this presentation author deals with history, conception and exploitation of information portal about environment in the Slovak Republic. This portal - Enviroportal.sk was introduced into service in testing operation in April 2005. Perspectives of Enviroportal.sk are discussed

  8. Portal vein thrombosis after splenectomy for beta-thalassemia major

    International Nuclear Information System (INIS)

    Al-Hawsawi, Zakaria M.; Tarawah, Ahmed M.; Hassan, Ruhul Amin A.; Haouimi, Ammar S.

    2004-01-01

    Portal vein thrombosis is a recognized complication after splenectomy for beta-thalassemia major due to the chronic hypercoagulable state which has been recognized to exist in childhood thalassemia and contribute to thromboembolic events. We reporting one patient with beta-thalassemia major developed portal vein thrombosis following splenectomy. (author)

  9. Portal: Your Door to World Languages and Cultures

    Science.gov (United States)

    Elliott, Don; Lawton, Rachele

    2009-01-01

    Portal: Your Door to World Languages and Cultures was a series of public cultural events, in a variety of formats, created through a new partnership between the credit and continuing education (noncredit) foreign language programs at the Community College of Baltimore County (CCBC). Portal was designed to cultivate interest in foreign languages…

  10. Improving image quality in portal venography with spectral CT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Li-qin, E-mail: zhaolqzr@sohu.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); He, Wen, E-mail: hewen1724@sina.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Li, Jian-ying, E-mail: jianying.li@med.ge.com [CT Advanced Application and Research, GE Healthcare, 100176 China (China); Chen, Jiang-hong, E-mail: chenjianghong1973@hotmail.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Wang, Ke-yang, E-mail: ke7ke@sina.com [Department of Radiology, Beijing Friendship Hospital Affiliated to Capital Medical University, Beijing,100050 (China); Tan, Li, E-mail: Litan@ge.com [CT product, GE Healthcare, 100176 China (China)

    2012-08-15

    Objective: To investigate the effect of energy spectral CT on the image quality of CT portal venography in cirrhosis patients. Materials and methods: 30 portal hypertension patients underwent spectral CT examination using a single-tube, fast dual tube voltage switching technique. 101 sets of monochromatic images were generated from 40 keV to 140 keV. Image noise and contrast-to-noise ratio (CNR) for portal veins from the monochromatic images were measured. An optimal monochromatic image set was selected for obtaining the best CNR for portal veins. The image noise and CNR of the intra-hepatic portal vein and extra-hepatic main stem at the selected monochromatic level were compared with those from the conventional polychromatic images. Image quality was also assessed and compared. Results: The monochromatic images at 51 keV were found to provide the best CNR for both the intra-hepatic and extra-hepatic portal veins. At this energy level, the monochromatic images had about 100% higher CNR than the polychromatic images with a moderate 30% noise increase. The qualitative image quality assessment was also statistically higher with monochromatic images at 51 keV. Conclusion: Monochromatic images at 51 keV for CT portal venography could improve CNR for displaying hepatic portal veins and improve the overall image quality.

  11. Managing a portal of digital web resources by content syndication

    NARCIS (Netherlands)

    van der Vet, P.E.; Hofmann, Martin; Huibers, Theo W.C.; Roosendaal, Hans E.; de Bra, P.

    2003-01-01

    As users become more accustomed to continuous Internet access, they will have less patience with the offering of disparate resources. A new generation of portals is being designed that aids users in navigating resource space and in processing the data they retrieved. Such portals offer added value

  12. questions as engagement strategies in nigerian job portals online

    African Journals Online (AJOL)

    rotimi

    2012-09-13

    Sep 13, 2012 ... Key words: questions, engagement strategy, job portal, Nigeria, unemployment .... Job portals offer different services, such as ..... softer disciplines (philosophy, sociology, applied linguistics and marketing) than the .... constructed based on a hypothetical case and used to bring readers into an imaginary.

  13. Gap filling strategies for long term energy flux data sets

    DEFF Research Database (Denmark)

    Falge, E.; Baldocchi, D.; Olson, R.

    2001-01-01

    At present a network of over 100 field sites are measuring carbon dioxide, water vapor and sensible heat fluxes between the biosphere and atmosphere, on a nearly continuous basis. Gaps in the long term measurements of evaporation and sensible heat flux must be filled before these data can be used...... for hydrological and meteorological applications. We adapted methods of gap filling for NEE (net ecosystem exchange of carbon) to energy fluxes and applied them to data sets available from the EUROFLUX and AmeriFlux eddy covariance databases. The average data coverage for the sites selected was 69% and 75......% for latent heat (lambdaE) and sensible heat (H). The methods were based on mean diurnal variations (half-hourly binned means of fluxes based on previous and subsequent days, MDV) and look-up tables for fluxes during assorted meteorological conditions (LookUp), and the impact of different gap filling methods...

  14. Angiographic diagnosis of the prehepatic portal hypertension

    International Nuclear Information System (INIS)

    Carnevali, G.; Brambilla, G.

    1981-01-01

    After the experience gained in the examination of more than 400 patients with portal hypertension, one can say that thrombosis is a factor not to be neglected. It appeared in 25% of all cases, in 50% of all cases as a cause of liver cirrhosis. The representation of the vena coeliaca mesentenica is essential for a reliable detection of thrombosis. Splenoportography is less frequently applied due to the known contraindications and is restricted to more demanding and complex problems. The detection of thrombotic changes is also important because such areas prohibit surgical measures such as by-passes. Also important is the preventive discovery of a portal thrombosis in the course of a complicated, bleeding liver cirrhosis. A pre-operative angiographic diagnosis is necessary in planned portocaval shunt procedures of cirrholic liver alterations. The surgeon has to know beforehand whether pyle thrombosis can be excluded or detected. In the latter case, a thrombotectomy has to be performed, which, however, does not impede good treatment results. (orig./MG) [de

  15. Angiographic diagnosis of the prehepatic portal hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Carnevali, G; Brambilla, G

    1981-01-01

    After the experience gained in the examination of more than 400 patients with portal hypertension, one can say that thrombosis is a factor not to be neglected. It appeared in 25% of all cases and in 50% of all cases as a cause of liver cirrhosis. The representation of the vena coeliaca mesentenica is essential for a reliable detection of thrombosis. Splenoportography is less frequently applied due to the known contraindications and is restricted to more demanding and complex problems. The detection of thrombotic changes is also important because such areas prohibit surgical measures such as by-passes. Also important is the preventive discovery of a portal thrombosis in the course of a complicated, bleeding liver cirrhosis. A pre-operative angiographic diagnosis is necessary in planned portocaval shunt procedures of cirrholic liver alterations. The surgeon has to know beforehand whether pyle thrombosis can be excluded or detected. In the latter case, a thrombotectomy has to be performed, which, however, does not impede good treatment results.

  16. The Anatomy of a Grid portal

    International Nuclear Information System (INIS)

    Licari, Daniele; Calzolari, Federico

    2011-01-01

    In this paper we introduce a new way to deal with Grid portals referring to our implementation. L-GRID is a light portal to access the EGEE/EGI Grid infrastructure via Web, allowing users to submit their jobs from a common Web browser in a few minutes, without any knowledge about the Grid infrastructure. It provides the control over the complete lifecycle of a Grid Job, from its submission and status monitoring, to the output retrieval. The system, implemented as client-server architecture, is based on the Globus Grid middleware. The client side application is based on a java applet; the server relies on a Globus User Interface. There is no need of user registration on the server side, and the user needs only his own X.509 personal certificate. The system is user-friendly, secure (it uses SSL protocol, mechanism for dynamic delegation and identity creation in public key infrastructures), highly customizable, open source, and easy to install. The X.509 personal certificate does not get out from the local machine. It allows to reduce the time spent for the job submission, granting at the same time a higher efficiency and a better security level in proxy delegation and management.

  17. A web portal for hydrodynamical, cosmological simulations

    Science.gov (United States)

    Ragagnin, A.; Dolag, K.; Biffi, V.; Cadolle Bel, M.; Hammer, N. J.; Krukau, A.; Petkova, M.; Steinborn, D.

    2017-07-01

    This article describes a data centre hosting a web portal for accessing and sharing the output of large, cosmological, hydro-dynamical simulations with a broad scientific community. It also allows users to receive related scientific data products by directly processing the raw simulation data on a remote computing cluster. The data centre has a multi-layer structure: a web portal, a job control layer, a computing cluster and a HPC storage system. The outer layer enables users to choose an object from the simulations. Objects can be selected by visually inspecting 2D maps of the simulation data, by performing highly compounded and elaborated queries or graphically by plotting arbitrary combinations of properties. The user can run analysis tools on a chosen object. These services allow users to run analysis tools on the raw simulation data. The job control layer is responsible for handling and performing the analysis jobs, which are executed on a computing cluster. The innermost layer is formed by a HPC storage system which hosts the large, raw simulation data. The following services are available for the users: (I) CLUSTERINSPECT visualizes properties of member galaxies of a selected galaxy cluster; (II) SIMCUT returns the raw data of a sub-volume around a selected object from a simulation, containing all the original, hydro-dynamical quantities; (III) SMAC creates idealized 2D maps of various, physical quantities and observables of a selected object; (IV) PHOX generates virtual X-ray observations with specifications of various current and upcoming instruments.

  18. The Anatomy of a Grid portal

    Science.gov (United States)

    Licari, Daniele; Calzolari, Federico

    2011-12-01

    In this paper we introduce a new way to deal with Grid portals referring to our implementation. L-GRID is a light portal to access the EGEE/EGI Grid infrastructure via Web, allowing users to submit their jobs from a common Web browser in a few minutes, without any knowledge about the Grid infrastructure. It provides the control over the complete lifecycle of a Grid Job, from its submission and status monitoring, to the output retrieval. The system, implemented as client-server architecture, is based on the Globus Grid middleware. The client side application is based on a java applet; the server relies on a Globus User Interface. There is no need of user registration on the server side, and the user needs only his own X.509 personal certificate. The system is user-friendly, secure (it uses SSL protocol, mechanism for dynamic delegation and identity creation in public key infrastructures), highly customizable, open source, and easy to install. The X.509 personal certificate does not get out from the local machine. It allows to reduce the time spent for the job submission, granting at the same time a higher efficiency and a better security level in proxy delegation and management.

  19. Perturbative unitarity constraints on gauge portals

    Science.gov (United States)

    El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

    2017-12-01

    Dark matter that was once in thermal equilibrium with the Standard Model is generally prohibited from obtaining all of its mass from the electroweak phase transition. This implies a new scale of physics and mediator particles to facilitate dark matter annihilation. In this work, we focus on dark matter that annihilates through a generic gauge boson portal. We show how partial wave unitarity places upper bounds on the dark gauge boson, dark Higgs and dark matter masses. Outside of well-defined fine-tuned regions, we find an upper bound of 9 TeV for the dark matter mass when the dark Higgs and dark gauge bosons both facilitate the dark matter annihilations. In this scenario, the upper bound on the dark Higgs and dark gauge boson masses are 10 TeV and 16 TeV, respectively. When only the dark gauge boson facilitates dark matter annihilations, we find an upper bound of 3 TeV and 6 TeV for the dark matter and dark gauge boson, respectively. Overall, using the gauge portal as a template, we describe a method to not only place upper bounds on the dark matter mass but also on the new particles with Standard Model quantum numbers. We briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.

  20. Developing patient portals in a fragmented healthcare system.

    Science.gov (United States)

    Otte-Trojel, Terese; de Bont, Antoinette; Aspria, Marcello; Adams, Samantha; Rundall, Thomas G; van de Klundert, Joris; de Mul, Marleen

    2015-10-01

    Use of patient portals may contribute to improved patient health and experiences and better organizational performance. In the Netherlands, patient portals have gained considerable attention in recent years, as evidenced by various policy initiatives and practical efforts directed at developing portals. Due to the fragmented setup of the Dutch healthcare system patient portals that give patients access to information and services from across their providers are developed in inter-organizational collaboration. The objective of this paper is to identify and describe the types of collaborations, or networks, that have been established to develop patient portals in the Netherlands. Understanding the characteristics of these networks as well as the development of their respective portals enables us to assess the enabling and constraining effects of different network types on patient portal initiatives. We used qualitative methods including interview and documents analysis. In a first step, we interviewed eighteen experts and reviewed relevant national policy and strategy documents. Based on this orientation, we selected three networks we deemed to be representative of inter-organizational efforts to develop Dutch patient portals in 2012. In a second step, we interviewed twelve representatives of these patient portal networks and collected documents related to the portals. We applied content analytic techniques to analyze data from the three cases. The three studied networks differed in their number and diversity of actors, the degree to which these actors were mutually dependent, the degree to which network governance was decentralized, and the dynamics of the network structures. We observed that the portals developed in networks displaying the highest degree of these characteristics experienced most difficulties associated with developing patient portals - such as achieving interoperability, successful implementation, regulatory complaisance, and financial

  1. The ADRICOSM STAR GeoPortal

    Science.gov (United States)

    Giorgetti, Alessandra; Cesarini, Claudia; Gambetta, Marco; Reseghetti, Franco; Vinci, Matteo

    2010-05-01

    From Stockholm (1972) to Rio de Janeiro (1992) and to Johannesburg (2002), environmental protection objectives are related to the principles of sustainable development. This includes the following important components: participation, information, communication, training (capacity building) and education. Better information ensure more participation from individuals, and allows citizens to take part in many different actions that can influence the policy process. Participation to political decisions need access to reliable and quality controlled information. The ADRICOSM Portal was developed in order to manage data diversity, provide access to any kind of product, provide metadata completeness and accuracy. The product, as defined in ADRICOSM, is anything that can be offered to a client and that might satisfy a want or need. This implied the implementation of services that was taking into consideration the diversity of the objects to be provided to users: observations, model outputs, maps, etc. The implementation of the portal was based on two metadata levels: 1. Directory level - consisting of broad descriptions of the contents of data sets; used to locate data sets of potential interest and 2. Data level - consisting of the actual data objects. The portal was developed as a simplified front end for the partners data management systems, giving emphasis on federated access points focused on thematic aspects. This was based on the idea that specialized customer-related access points can be better carried out by delegated teams of experts who know the needs of different customers, define the user software which is most suited to them. The data management systems provide facilities for two data tracks, one in real-time (or near-realtime) and one in delayed mode. Both tracks are based on the same data sources and transmission systems, but the data follow different routes and are processed differently depending on user requirements. The real-time data and model products

  2. The SmartGeo Portal: A retrospective

    Science.gov (United States)

    Heilmann, Zeno; Satta, Guido; Bonomi, Ernesto

    2016-04-01

    The SmartGeo portal was created in a follow-up project that evolved from the geophysical data imaging services of a Grid computing portal for Geoscience, called GRIDA3. The scope of the project was to support commercial geotechnical service providers as well as academic researchers working in near-surface geoscience. Starting from the existing services, the SmartGeo portal was set up on new hardware, using the latest version of the grid portal environment EnginFrame. After a first working version was established, the services were reviewed, updated and accompanied by new services according to the feedback we received from our partners. One partner for instance experienced large difficulties in a project that aimed at delineating the aquifer for finding water pollutant substances in an industrial area of Basel. The seismic imaging service inherited from the previous portal was employing a data-driven algorithm optimized to provide, directly during data acquisition, nearly in real-time a first image of the subsurface structure. Different to this, our user needed for his data from a geologically very complex and noisy urban environment the maximum lateral resolution and noise reduction possible. For this purpose we added two cutting edge data imaging algorithms able to deliver such high precision results by simultaneously optimizing, for every single image point, all parameters of the mathematical model---a procedure which increased the computational effort by one or two magnitudes, respectively. Thus, parallel computing on grid infrastructure served for maximizing the image resolution instead for generating real-time results. This proved also very useful for the data of an academic partner, recorded for imaging the structure of a shallow sedimentary basin, where we could obtain strongly improved seismic velocity information using these new algorithms. A general user request was to implement interactive data visualization tools. To fulfill this demand we took

  3. Advances in the management of childhood portal hypertension.

    Science.gov (United States)

    McKiernan, Patrick; Abdel-Hady, Mona

    2015-05-01

    Portal hypertension is one of the most serious complications of childhood liver disease, and variceal bleeding is the most feared complication. Most portal hypertension results from cirrhosis but extra hepatic portal vein obstruction is the single commonest cause. Upper gastrointestinal endoscopy endoscopy remains necessary to diagnose gastro-esophageal varices. Families of children with portal hypertension should be provided with written instructions in case of gastrointestinal bleeding. Children with large varices should be considered for primary prophylaxis on a case-by-case basis. The preferred method is variceal band ligation. Children with acute bleeding should be admitted to hospital and treated with antibiotics and pharmacotherapy before urgent therapeutic endoscopy. All children who have bled should then receive secondary prophylaxis. The preferred method is variceal band ligation and as yet there is little evidence to support the use of β-blockers. Children with extrahepatic portal vein obstruction should be assessed for suitability of mesoportal bypass.

  4. Advances in the treatment of portal hypertension in cirrhosis.

    Science.gov (United States)

    Kimer, N; Wiese, S; Mo, S; Møller, S; Bendtsen, F

    2016-08-01

    Non-selective beta-blockers and handling of esophageal varices has been key elements in the treatment of portal hypertension in recent decades. Liver vein catheterization has been essential in diagnosis and monitoring of portal hypertension, but ongoing needs for noninvasive tools has led to research in areas of both biomarkers, and transient elastography, which displays promising results in discerning clinically significant portal hypertension. Novel research into the areas of hepatic stellate cell function and the dynamic components of portal hypertension has revealed promising areas of treatment modalities, targeting intestinal decontamination, angiogenesis, inflammation and oxidative stress. Future studies may reveal if these initiatives lead to developments of new drugs for treatment of portal hypertension.

  5. Advances in the treatment of portal hypertension in cirrhosis

    DEFF Research Database (Denmark)

    Kimer, Nina; Wiese, S; Mo, S S

    2016-01-01

    Non-selective beta-blockers and handling of esophageal varices has been key elements in the treatment of portal hypertension in recent decades. Liver vein catheterization has been essential in diagnosis and monitoring of portal hypertension, but ongoing needs for noninvasive tools has led...... to research in areas of both biomarkers, and transient elastography, which displays promising results in discerning clinically significant portal hypertension. Novel research into the areas of hepatic stellate cell function and the dynamic components of portal hypertension has revealed promising areas...... of treatment modalities, targeting intestinal decontamination, angiogenesis, inflammation and oxidative stress. Future studies may reveal if these initiatives lead to developments of new drugs for treatment of portal hypertension....

  6. A Web portal for CMS Grid job submission and management

    Energy Technology Data Exchange (ETDEWEB)

    Braun, David [Department of Physics, Purdue University, W. Lafayette, IN 47907 (United States); Neumeister, Norbert, E-mail: neumeist@purdue.ed [Rosen Center for Advanced Computing, Purdue University, W. Lafayette, IN 47907 (United States)

    2010-04-01

    We present a Web portal for CMS Grid submission and management. The portal is built using a JBoss application server. It has a three tier architecture; presentation, business logic and data. Bean based business logic interacts with the underlying Grid infrastructure and pre-existing external applications, while the presentation layer uses AJAX to offer an intuitive, functional interface to the back-end. Application data aggregating information from the portal as well as the external applications is persisted to the server memory cache and then to a backend database. We describe how the portal exploits standard, off-the-shelf commodity software together with existing Grid infrastructures in order to facilitate job submission and monitoring for the CMS collaboration. This paper describes the design, development, current functionality and plans for future enhancements of the portal.

  7. Interface methods for using intranet portal organizational memory information system.

    Science.gov (United States)

    Ji, Yong Gu; Salvendy, Gavriel

    2004-12-01

    In this paper, an intranet portal is considered as an information infrastructure (organizational memory information system, OMIS) supporting organizational learning. The properties and the hierarchical structure of information and knowledge in an intranet portal OMIS was identified as a problem for navigation tools of an intranet portal interface. The problem relates to navigation and retrieval functions of intranet portal OMIS and is expected to adversely affect user performance, satisfaction, and usefulness. To solve the problem, a conceptual model for navigation tools of an intranet portal interface was proposed and an experiment using a crossover design was conducted with 10 participants. In the experiment, a separate access method (tabbed tree tool) was compared to an unified access method (single tree tool). The results indicate that each information/knowledge repository for which a user has a different structural knowledge should be handled separately with a separate access to increase user satisfaction and the usefulness of the OMIS and to improve user performance in navigation.

  8. A Web portal for CMS Grid job submission and management

    International Nuclear Information System (INIS)

    Braun, David; Neumeister, Norbert

    2010-01-01

    We present a Web portal for CMS Grid submission and management. The portal is built using a JBoss application server. It has a three tier architecture; presentation, business logic and data. Bean based business logic interacts with the underlying Grid infrastructure and pre-existing external applications, while the presentation layer uses AJAX to offer an intuitive, functional interface to the back-end. Application data aggregating information from the portal as well as the external applications is persisted to the server memory cache and then to a backend database. We describe how the portal exploits standard, off-the-shelf commodity software together with existing Grid infrastructures in order to facilitate job submission and monitoring for the CMS collaboration. This paper describes the design, development, current functionality and plans for future enhancements of the portal.

  9. Stent Recanalization of Chronic Portal Vein Occlusion in a Child

    International Nuclear Information System (INIS)

    Cwikiel, Wojciech; Solvig, Jan; Schroder, Henrik

    2000-01-01

    An 8-year-old boy with a 21/2 year history of portal hypertension and repeated bleedings from esophageal varices, was referred for treatment. The 3.5-cm-long occlusion of the portal vein was passed and the channel created was stabilized with a balloon-expandable stent; a portosystemic stent-shunt was also created. The portosystemic shunt closed spontaneously within 1 month, while the recanalized segment of the portal vein remained open. The pressure gradient between the intrahepatic and extrahepatic portal vein branches dropped from 17 mmHg to 0 mmHg. The pressure in the portal vein dropped from 30 mmHg to 17 mmHg and the bleedings stopped. The next dilation of the stent was performed 12 months later due to an increased pressure gradient; the gastroesophageal varices disappeared completely. Further dilation of the stent was planned after 2, 4, and 6 years

  10. LBA-ECO TG-08 Soil Gas Flux after Forest and Pasture Fertilization, Rondonia, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — ABSTRACT: This data set provides nitric oxide (NO), nitrous oxide (N2O), carbon dioxide (CO2) flux measurements, nitrogen (N) and phosphorus (P) pools, net N...

  11. Splanchnic-aortic inflammatory axis in experimental portal hypertension

    Science.gov (United States)

    Aller, Maria-Angeles; de las Heras, Natalia; Nava, Maria-Paz; Regadera, Javier; Arias, Jaime; Lahera, Vicente

    2013-01-01

    Splanchnic and systemic low-grade inflammation has been proposed to be a consequence of long-term prehepatic portal hypertension. This experimental model causes minimal alternations in the liver, thus making a more selective study possible for the pathological changes characteristic of prehepatic portal hypertension. Low-grade splanchnic inflammation after long-term triple partial portal vein ligation could be associated with liver steatosis and portal hypertensive intestinal vasculopathy. In fact, we have previously shown that prehepatic portal hypertension in the rat induces liver steatosis and changes in lipid and carbohydrate metabolism similar to those produced in chronic inflammatory conditions described in metabolic syndrome in humans. Dysbiosis and bacterial translocation in this experimental model suggest the existence of a portal hypertensive intestinal microbiome implicated in both the splanchnic and systemic alterations related to prehepatic portal hypertension. Among the systemic impairments, aortopathy characterized by oxidative stress, increased levels of proinflammatory cytokines and profibrogenic mediators stand out. In this experimental model of long-term triple portal vein ligated-rats, the abdominal aortic proinflammatory response could be attributed to oxidative stress. Thus, the increased aortic reduced-nicotinamide-adenine dinucleotide phosphate [NAD(P)H] oxidase activity could be associated with reactive oxygen species production and promote aortic inflammation. Also, oxidative stress mediated by NAD(P)H oxidase has been associated with risk factors for inflammation and atherosclerosis. The splanchnic and systemic pathology that is produced in the long term after triple partial portal vein ligation in the rat reinforces the validity of this experimental model to study the chronic low-grade inflammatory response induced by prehepatic portal hypertension. PMID:24307792

  12. Stoichiometry and Life-History Interact to Determine the Magnitude of Cross-Ecosystem Element and Biomass Fluxes

    Directory of Open Access Journals (Sweden)

    Thomas M. Luhring

    2017-05-01

    Full Text Available Ecosystems are linked through the transfer of materials and energy. Studies examining material fluxes across habitat boundaries frequently quantify unidirectional flows of nutrients and energy. However, material fluxes can be multidirectional, and we lack a conceptual framework to describe how their quantity and stoichiometry influence the net transfer of individual elements between ecosystems. Here we develop a zero net transfer isocline (ZNTI framework that integrates the relative mass and stoichiometry of fluxes into and out of an ecosystem. We then use case studies with amphibians and salmon to elucidate how life history, ontogenetic shifts in stoichiometry, and trophic interactions shape relative fluxes of nutrients between aquatic and terrestrial ecosystems. Because they increase in both size and Ca content from ova to metamorphs, amphibian life histories strongly bias them toward net Ca export into the terrestrial environment. Because amphibian biomass, C, P, and Ca ZNTIs do not overlap, there is no value of survivorship where the net flux of biomass, C, P, and Ca are simultaneously balanced between terrestrial and aquatic habitats. The degree of iteroparity and semelparity in salmon strongly affects both the magnitude of net biomass and P flux between riverine and marine environments. While the net direction of biomass flux generally remains strongly biased toward import into the riverine system, net P flux can reach net export into the marine environment because of increasing adult breeding survival leading to reduced mass and %P of what they deposit in rivers (e.g., ova vs. whole carcasses. These examples highlight how ontogenetic shifts in body size and stoichiometry result in asymmetric fluxes of elements and biomass that can lead to simultaneous net imports and exports of different elements within the same system. Furthermore, they demonstrate how changes in life-history characteristics and stage-specific survivorship can lead to

  13. Altered blood-brain barrier permeability in rats with prehepatic portal hypertension turns to normal when portal pressure is lowered

    Science.gov (United States)

    Eizayaga, Francisco; Scorticati, Camila; Prestifilippo, Juan P; Romay, Salvador; Fernandez, Maria A; Castro, José L; Lemberg, Abraham; Perazzo, Juan C

    2006-01-01

    AIM: To study the blood-brain barrier integrity in prehepatic portal hypertensive rats induced by partial portal vein ligation, at 14 and 40 d after ligation when portal pressure is spontaneously normalized. METHODS: Adult male Wistar rats were divided into four groups: Group I: Sham14d , sham operated; Group II: PH14d , portal vein stenosis; (both groups were used 14 days after surgery); Group III: Sham40d, Sham operated and Group IV: PH40d Portal vein stenosis (Groups II and IV used 40 d after surgery). Plasma ammonia, plasma and cerebrospinal fluid protein and liver enzymes concentrations were determined. Trypan and Evans blue dyes, systemically injected, were investigated in hippocampus to study blood-brain barrier integrity. Portal pressure was periodically recorded. RESULTS: Forty days after stricture, portal pressure was normalized, plasma ammonia was moderately high, and both dyes were absent in central nervous system parenchyma. All other parameters were reestablished. When portal pressure was normalized and ammonia level was lowered, but not normal, the altered integrity of blood-brain barrier becomes reestablished. CONCLUSION: The impairment of blood-brain barrier and subsequent normalization could be a mechanism involved in hepatic encephalopathy reversibility. Hemodynamic changes and ammonia could trigger blood-brain barrier alterations and its reestablishment. PMID:16552803

  14. Combined Rex-bypass shunt with pericardial devascularization alleviated prehepatic portal hypertension caused by cavernomatous transformation of portal vein.

    Science.gov (United States)

    Wang, Ruo-Yi; Wang, Jun-Feng; Liu, Qian; Ma, Nan; Chen, Wei-Xiu; Li, Jin-Liang

    2017-09-01

    To evaluate the effects of combined Rex-bypass shunt and pericardial devascularization on prehepatic portal hypertension secondary to cavernomatous transformation of portal vein (CTPV). Forty-two patients aged from 3 years to 49 years (divided into 3 groups), 26 cases male and 16 female, with prehepatic vascular hepertention were treated with Rex-bypass shunt combined with pericardial devascularization. In each patient, preoperative assessment included ultrasound and computed tomographic angiography of the portal vein and blood analysis. The procedure was Rex-bypass shunt (with or without graft), and patients with moderate or severe gastroesophageal varices required additional paraesophagogastric devascularization. Splenectomy or subtotal splenectomy was performed if combined hypersplenism co-existed. All data were analyzed retrospectively. No intraoperative death occurred, blood routine analysis improved (P portal vein (LPV) significantly increased, the esophageal and gastric varices significantly relieved in 34 patients (P portal hypertension caused by CTPV.

  15. Quantitative study of the hemodynamic changes of portal vein in hepatocellular carcinoma with arterioportal shunts

    International Nuclear Information System (INIS)

    Shen Xinying; Shan Hong

    2005-01-01

    Objective: To measure the changes of portal venous pressure before and after APS by percutaneous portal vein catheterization and to quantitatively analyse the correlation between portal pressure and portal hypertension. Methods: All the 18 central arterioportal shunts (APS) patients with hepatocellular carcinoma (HCC) were treated with embolization of APS and TACE, and the pressure of portal vein was measured by percutaneous portal vein catheterization pre- and post-embolization of APS. Color doppler sonography and endoscopy were employed to investigate before and 2 weeks after embolization in all patients. Results: The pressure of portal vein decreased significantly after embolization, and the decreased rate was 5.4%-33.3% with the mean rate 20.1%. After the embolization, the width of portal vein decreased and the blood flow velocity of portal vein increased significantly, P<0.01. Hepatofugal portal venous flow was seen in 13 patients before embolization, and restored to hepatopetal flow in 7 patients after embolization. In the 10 patients with more than 20% decrease in portal venous pressure, the portal hypertension improved markedly; while in other 8 patients with less than 20 percent decrease in portal venous pressure, the clinical symptoms of portal hypertension did not improve as much. Conclusions: Embolization of APS can decrease portal venous pressure, with the mean decreasing rate over 20%. Decreasing by 20% or more of portal venous pressure can improve effectively the portal hypertension symptoms including ascites, variceal bleeding, and diarrhea. (authors)

  16. MR image-guided portal verification for brain treatment field

    International Nuclear Information System (INIS)

    Yin Fangfang; Gao Qinghuai; Xie Huchen; Nelson, Diana F.; Yu Yan; Kwok, W. Edmund; Totterman, Saara; Schell, Michael C.; Rubin, Philip

    1998-01-01

    Purpose: To investigate a method for the generation of digitally reconstructed radiographs directly from MR images (DRR-MRI) to guide a computerized portal verification procedure. Methods and Materials: Several major steps were developed to perform an MR image-guided portal verification procedure. Initially, a wavelet-based multiresolution adaptive thresholding method was used to segment the skin slice-by-slice in MR brain axial images. Some selected anatomical structures, such as target volume and critical organs, were then manually identified and were reassigned to relatively higher intensities. Interslice information was interpolated with a directional method to achieve comparable display resolution in three dimensions. Next, a ray-tracing method was used to generate a DRR-MRI image at the planned treatment position, and the ray tracing was simply performed on summation of voxels along the ray. The skin and its relative positions were also projected to the DRR-MRI and were used to guide the search of similar features in the portal image. A Canny edge detector was used to enhance the brain contour in both portal and simulation images. The skin in the brain portal image was then extracted using a knowledge-based searching technique. Finally, a Chamfer matching technique was used to correlate features between DRR-MRI and portal image. Results: The MR image-guided portal verification method was evaluated using a brain phantom case and a clinical patient case. Both DRR-CT and DRR-MRI were generated using CT and MR phantom images with the same beam orientation and then compared. The matching result indicated that the maximum deviation of internal structures was less than 1 mm. The segmented results for brain MR slice images indicated that a wavelet-based image segmentation technique provided a reasonable estimation for the brain skin. For the clinical patient case with a given portal field, the MR image-guided verification method provided an excellent match between

  17. Partitioning inter annual variability in net ecosystem exchange between climatic variability and functional change

    International Nuclear Information System (INIS)

    Hui, D.; Luo, Y.; Katul, G.

    2003-01-01

    Inter annual variability in net ecosystem exchange of carbon is investigated using a homogeneity-of-slopes model to identify the function change contributing to inter annual variability, net ecosystem carbon exchange, and night-time ecosystem respiration. Results of employing this statistical approach to a data set collected at the Duke Forest AmeriFlux site from August 1997 to December 2001 are discussed. The results demonstrate that it is feasible to partition the variation in ecosystem carbon fluxes into direct effects of seasonal and inter annual climatic variability and functional change. 51 refs., 4 tabs., 5 figs

  18. Evaluation of NASA's Carbon Monitoring System (CMS) Flux Pilot: Terrestrial CO2 Fluxes

    Science.gov (United States)

    Fisher, J. B.; Polhamus, A.; Bowman, K. W.; Collatz, G. J.; Potter, C. S.; Lee, M.; Liu, J.; Jung, M.; Reichstein, M.

    2011-12-01

    NASA's Carbon Monitoring System (CMS) flux pilot project combines NASA's Earth System models in land, ocean and atmosphere to track surface CO2 fluxes. The system is constrained by atmospheric measurements of XCO2 from the Japanese GOSAT satellite, giving a "big picture" view of total CO2 in Earth's atmosphere. Combining two land models (CASA-Ames and CASA-GFED), two ocean models (ECCO2 and NOBM) and two atmospheric chemistry and inversion models (GEOS-5 and GEOS-Chem), the system brings together the stand-alone component models of the Earth System, all of which are run diagnostically constrained by a multitude of other remotely sensed data. Here, we evaluate the biospheric land surface CO2 fluxes (i.e., net ecosystem exchange, NEE) as estimated from the atmospheric flux inversion. We compare against the prior bottom-up estimates (e.g., the CASA models) as well. Our evaluation dataset is the independently derived global wall-to-wall MPI-BGC product, which uses a machine learning algorithm and model tree ensemble to "scale-up" a network of in situ CO2 flux measurements from 253 globally-distributed sites in the FLUXNET network. The measurements are based on the eddy covariance method, which uses observations of co-varying fluxes of CO2 (and water and energy) from instruments on towers extending above ecosystem canopies; the towers integrate fluxes over large spatial areas (~1 km2). We present global maps of CO2 fluxes and differences between products, summaries of fluxes by TRANSCOM region, country, latitude, and biome type, and assess the time series, including timing of minimum and maximum fluxes. This evaluation shows both where the CMS is performing well, and where improvements should be directed in further work.

  19. Effect of TIPS placement on portal and splanchnic arterial blood flow in 4-dimensional flow MRI

    Energy Technology Data Exchange (ETDEWEB)

    Stankovic, Zoran [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); University Medical Center Freiburg, Department of Diagnostic Radiology and Medical Physics, Freiburg (Germany); Roessle, Martin; Schultheiss, Michael [University Medical Center Freiburg, Department of Gastroenterology, Freiburg (Germany); Euringer, Wulf; Langer, Mathias [University Medical Center Freiburg, Department of Diagnostic Radiology and Medical Physics, Freiburg (Germany); Salem, Riad; Barker, Alex; Carr, James; Collins, Jeremy D. [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Markl, Michael [Northwestern University, Department of Radiology, Feinberg School of Medicine, Chicago, IL (United States); Northwestern University, Department of Biomedical Engineering, McCormick School of Engineering, Chicago, IL (United States)

    2015-09-15

    To assess changes in portal and splanchnic arterial haemodynamics in patients undergoing transjugular intrahepatic portosystemic shunt (TIPS) using four-dimensional (4D) flow MRI, a non-invasive, non-contrast imaging technique. Eleven patients undergoing TIPS implantation were enrolled. K-t GRAPPA accelerated non-contrast 4D flow MRI of the liver vasculature was applied with acceleration factor R = 5 at 3Tesla. Flow analysis included three-dimensional (3D) blood flow visualization using time-resolved 3D particle traces and semi-quantitative flow pattern grading. Quantitative evaluation entailed peak velocities and net flows throughout the arterial and portal venous (PV) systems. MRI measurements were taken within 24 h before and 4 weeks after TIPS placement. Three-dimensional flow visualization with 4D flow MRI revealed good image quality with minor limitations in PV flow. Quantitative analysis revealed a significant increase in PV flow (562 ± 373 ml/min before vs. 1831 ± 965 ml/min after TIPS), in the hepatic artery (176 ± 132 ml/min vs. 354 ± 140 ml/min) and combined flow in splenic and superior mesenteric arteries (770 ml/min vs. 1064 ml/min). Shunt-flow assessment demonstrated stenoses in two patients confirmed and treated at TIPS revision. Four-dimensional flow MRI might have the potential to give new information about the effect of TIPS placement on hepatic perfusion. It may explain some unexpected findings in clinical observation studies. (orig.)

  20. Turbulent fluxes by "Conditional Eddy Sampling"

    Science.gov (United States)

    Siebicke, Lukas

    2015-04-01

    for the field (one to two orders of magnitude lower compared to current closed-path laser based eddy covariance systems). Potential applications include fluxes of CO2, CH4, N2O, VOCs and other tracers. Finally we assess the flux accuracy of the Conditional Eddy Sampling (CES) approach as in our real implementation relative to alternative techniques including eddy covariance (EC) and relaxed eddy accumulation (REA). We further quantify various sources of instrument and method specific measurement errors. This comparison uses real measurements of 20 Hz turbulent time series of 3D wind velocity, sonic temperature and CO2 mixing ratio over a mixed decidious forest at the 'ICOS' flux tower site 'Hainich', Germany. Results from a simulation using real wind and CO2 timeseries from the Hainich site from 30 April to 3 November 2014 and real instrument performance suggest that the maximum flux estimates error (50% and 75% error quantiles) from Conditional Eddy Sampling (CES) relative to the true flux is 1.3% and 10%, respectively for monthly net fluxes, 1.6% and 7%, respectively for daily net fluxes and 8% and 35%, respectively for 30-minute CO2 flux estimates. Those results from CES are promising and outperform our REA estimates by about a factor of 50 assuming REA with constant b value. Results include flux time series from the EC, CES and REA approaches from 30-min to annual resolution.