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Sample records for a-si electronic portal

  1. Investigation of the optimal backscatter for an aSi electronic portal imaging device.

    PubMed

    Ko, Lung; Kim, Jong Oh; Siebers, Jeffrey V

    2004-05-07

    The effects of backscattered radiation on the dosimetric response of the Varian aS500 amorphous silicon electronic portal imaging device (EPID) are studied. Measurements demonstrate that radiation backscattered from the EPID mechanical support structure causes 5% asymmetries in the detected signal. To minimize the effect of backscattered radiation from the support structure, this work proposes adding material downstream of the EPID phosphor which provides uniform backscattering material to the phosphor and attenuates backscatter from the support structure before it reaches the phosphor. Two material locations were studied: downstream of the existing image cassette and within the cassette, immediately downstream of the flat-panel imager glass panel. Monte Carlo simulations were used to determine the thicknesses of water, Pb and Cu backscattering materials required to saturate the backscattered signal response for 6 MV and 18 MV beams for material thicknesses up to 50 mm. Water was unable to saturate the backscattered signal for thicknesses up to 50 mm for both energies. For Pb, to obtain a signal within 1% of saturation, 3 mm was required at 6 MV, and 6.8 mm was required at 18 MV. For Cu, thicknesses of 20.6 mm and 22.6 mm were required for the 6 MV and 18 MV beams, respectively. For saturation thicknesses, at 6 MV, the Cu backscatter enhanced the signal more than for Pb (Cu 1.25, Pb 1.11), but at 18 MV the reverse was found (Cu 1.19, Pb 1.23). This is due to the fact that at 6 MV, the backscattered radiation signal is dominated by low-energy scattered photons, which are readily attenuated by the Pb, while at 18 MV, electron backscatter contributes substantially to the signal. Image blurring caused by backscatter spread was less for Pb than Cu. Placing Pb immediately downstream of the glass panel further reduced the signal spread and increased the backscatter enhancement to 1.20 and 1.39 for the 6 MV and 18 MV beams, respectively. Overall, it is determined that

  2. Optimized Varian aSi portal dosimetry: development of datasets for collective use.

    PubMed

    Van Esch, Ann; Huyskens, Dominique P; Hirschi, Lukas; Baltes, Christof

    2013-11-04

    Although much literature has been devoted to portal dosimetry with the Varian amorphous silicon (aSi) portal imager, the majority of the described methods are not routinely adopted because implementation procedures are cumbersome and not within easy reach of most radiotherapy centers. To make improved portal dosimetry solutions more generally available, we have investigated the possibility of converting optimized configurations into ready-to-use standardized datasets. Firstly, for all commonly used photon energies (6, 10, 15, 18, and 20 MV), basic beam data acquired on 20 aSi panels were used to assess the interpanel reproducibility. Secondly, a standardized portal dose image prediction (PDIP) algorithm configuration was created for every energy, using a three-step process to optimize the aSi dose response function and profile correction files for the dosimetric calibration of the imager panel. An approximate correction of the backscatter of the Exact arm was also incorporated. Thirdly, a set of validation fields was assembled to assess the accuracy of the standardized configuration. Variations in the basic beam data measured on different aSi panels very rarely exceeded 2% (2 mm) and are of the same order of magnitude as variations between different Clinacs when measuring in reference conditions in water. All studied aSi panels can hence be regarded as nearly identical. Standardized datasets were successfully created and implemented. The test package proved useful in highlighting possible problems and illustrating remaining limitations, but also in demonstrating the good overall results (95% pass rate for 3%,3 mm) that can be obtained. The dosimetric behavior of all tested aSi panels was found to be nearly identical for all tested energies. The approach of using standardized datasets was then successfully tested through the creation and evaluation of PDIP preconfigured datasets that can be used within the Varian portal dosimetry solution.

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

    PubMed

    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.

  4. Pesticide Electronic Application Submission Portal Updated with New Features

    EPA Pesticide Factsheets

    EPA has published an updated version of the Pesticide Submission Portal. This Web-based system for electronic submission of pesticide registration applications to EPA, with new features and functionality.

  5. A Standardization Framework for Electronic Government Service Portals

    NASA Astrophysics Data System (ADS)

    Sarantis, Demetrios; Tsiakaliaris, Christos; Lampathaki, Fenareti; Charalabidis, Yannis

    Although most eGovernment interoperability frameworks (eGIFs) cover adequately the technical aspects of developing and supporting the provision of electronic services to citizens and businesses, they do not exclusively address several important areas regarding the organization, presentation, accessibility and security of the content and the electronic services offered through government portals. This chapter extends the scope of existing eGIFs presenting the overall architecture and the basic concepts of the Greek standardization framework for electronic government service portals which, for the first time in Europe, is part of a country's eGovernment framework. The proposed standardization framework includes standards, guidelines and recommendations regarding the design, development and operation of government portals that support the provision of administrative information and services to citizens and businesses. By applying the guidelines of the framework, the design, development and operation of portals in central, regional and municipal government can be systematically addressed resulting in an applicable, sustainable and ever-expanding framework.

  6. Use of electronic portal imaging devices for electron treatment verification.

    PubMed

    Kairn, T; Aland, T; Crowe, S B; Trapp, J V

    2016-03-01

    This study aims to help broaden the use of electronic portal imaging devices (EPIDs) for pre-treatment patient positioning verification, from photon-beam radiotherapy to photon- and electron-beam radiotherapy, by proposing and testing a method for acquiring clinically-useful EPID images of patient anatomy using electron beams, with a view to enabling and encouraging further research in this area. EPID images used in this study were acquired using all available beams from a linac configured to deliver electron beams with nominal energies of 6, 9, 12, 16 and 20 MeV, as well as photon beams with nominal energies of 6 and 10 MV. A widely-available heterogeneous, approximately-humanoid, thorax phantom was used, to provide an indication of the contrast and noise produced when imaging different types of tissue with comparatively realistic thicknesses. The acquired images were automatically calibrated, corrected for the effects of variations in the sensitivity of individual photodiodes, using a flood field image. For electron beam imaging, flood field EPID calibration images were acquired with and without the placement of blocks of water-equivalent plastic (with thicknesses approximately equal to the practical range of electrons in the plastic) placed upstream of the EPID, to filter out the primary electron beam, leaving only the bremsstrahlung photon signal. While the electron beam images acquired using a standard (unfiltered) flood field calibration were observed to be noisy and difficult to interpret, the electron beam images acquired using the filtered flood field calibration showed tissues and bony anatomy with levels of contrast and noise that were similar to the contrast and noise levels seen in the clinically acceptable photon beam EPID images. The best electron beam imaging results (highest contrast, signal-to-noise and contrast-to-noise ratios) were achieved when the images were acquired using the higher energy electron beams (16 and 20 MeV) when the EPID was

  7. MedlinePlus Connect: Linking Patient Portals and Electronic Health Records to Health Information

    MedlinePlus

    ... Patient portals, patient health record (PHR) systems, and electronic health record (EHR) systems can use MedlinePlus Connect ... patient portal, patient health record (PHR) system, or electronic health record (EHR) system sends a problem, medication, ...

  8. Operating range of a gas electron multiplier for portal imaging

    NASA Astrophysics Data System (ADS)

    Wallmark, M.; Brahme, A.; Danielsson, M.; Fonte, P.; Iacobaeus, C.; Peskov, V.; Östling, J.

    2001-09-01

    At the Karolinska Institute in Stockholm, Sweden a new detector for portal imaging is under development, which could greatly improve the alignment of the radiation beam with respect to the tumor during radiation treatment. The detector is based on solid converters combined with gas electron multipliers (GEMs) as an amplification structure. The detector has a large area and will be operated in a very high rate environment in the presence of heavy ionizing particles. As was discovered recently high rates and alpha particles could cause discharges in GEM and discharge propagation from GEM to GEM and to the readout electronics. Since reliability is one of the main requirements for the portal imaging device, we performed systematic studies to find a safe operating range of the device, free from typical high rate problems, such as discharges.

  9. A radiation-tolerant electronic readout system for portal imaging

    NASA Astrophysics Data System (ADS)

    Östling, J.; Brahme, A.; Danielsson, M.; Iacobaeus, C.; Peskov, V.

    2004-06-01

    A new electronic portal imaging device, EPID, is under development at the Karolinska Institutet and the Royal Institute of Technology. Due to considerable demands on radiation tolerance in the radiotherapy environment, a dedicated electronic readout system has been designed. The most interesting aspect of the readout system is that it allows to read out ˜1000 pixels in parallel, with all electronics placed outside the radiation beam—making the detector more radiation resistant. In this work we are presenting the function of a small prototype (6×100 pixels) of the electronic readout board that has been tested. Tests were made with continuous X-rays (10-60 keV) and with α particles. The results show that, without using an optimised gas mixture and with an early prototype only, the electronic readout system still works very well.

  10. Front-end electronics for the Muon Portal project

    NASA Astrophysics Data System (ADS)

    Garozzo, S.; Marano, D.; Bonanno, G.; Grillo, A.; Romeo, G.; Timpanaro, M. C.; Lo Presti, D.; Riggi, F.; Russo, V.; Bonanno, D.; La Rocca, P.; Longhitano, F.; Bongiovanni, D. G.; Fallica, G.; Valvo, G.

    2016-10-01

    The Muon Portal Project was born as a joint initiative between Italian research and industrial partners, aimed at the construction of a real-size working detector prototype to inspect the content of traveling containers by means of secondary cosmic-ray muon radiation and recognize potentially dangerous hidden materials. The tomographic image is obtained by reconstructing the incoming and outgoing muon trajectories when crossing the inspected volume, employing two tracker planes located above and below the container under inspection. In this paper, the design and development of the front-end electronics of the Muon Portal detector is presented, with particular emphasis being devoted to the photo-sensor devices detecting the scintillation light and to the read-out circuitry which is in charge of processing and digitizing the analog pulse signals. In addition, the remote control system, mechanical housing, and thermal cooling system of all structural blocks of the Muon Portal tracker are also discussed, demonstrating the effectiveness and functionality of the adopted design.

  11. Electronic Health Record Portal Adoption: a cross country analysis.

    PubMed

    Tavares, Jorge; Oliveira, Tiago

    2017-07-05

    This study's goal is to understand the factors that drive individuals to adopt Electronic Health Record (EHR) portals and to estimate if there are differences between countries with different healthcare models. We applied a new adoption model using as a starting point the extended Unified Theory of Acceptance and Use of Technology (UTAUT2) by incorporating the Concern for Information Privacy (CFIP) framework. To evaluate the research model we used the partial least squares (PLS) - structural equation modelling (SEM) approach. An online questionnaire was administrated in the United States (US) and Europe (Portugal). We collected 597 valid responses. The statistically significant factors of behavioural intention are performance expectancy ([Formula: see text] total  = 0.285; P < 0.01), effort expectancy ([Formula: see text] total  = 0.160; P < 0.01), social influence ([Formula: see text] total  = 0.198; P < 0.01), hedonic motivation ([Formula: see text] total  = -0.141; P < 0.01), price value ([Formula: see text] total  = 0.152; P < 0.01), and habit ([Formula: see text] total  = 0.255; P < 0.01). The predictors of use behaviour are habit ([Formula: see text] total  = 0.145; P < 0.01), and behavioural intention ([Formula: see text] total  = 0.480; P < 0.01). Social influence, hedonic motivation, and price value are only predictors in the US group. The model explained 53% of the variance in behavioural intention and 36% of the variance in use behaviour. Our study identified critical factors for the adoption of EHR portals and significant differences between the countries. Confidentiality issues do not seem to influence acceptance. The EHR portals usage patterns are significantly higher in US compared to Portugal.

  12. Dosimetric verification of radiation therapy including intensity modulated treatments, using an amorphous-silicon electronic portal imaging device

    NASA Astrophysics Data System (ADS)

    Chytyk-Praznik, Krista Joy

    Radiation therapy is continuously increasing in complexity due to technological innovation in delivery techniques, necessitating thorough dosimetric verification. Comparing accurately predicted portal dose images to measured images obtained during patient treatment can determine if a particular treatment was delivered correctly. The goal of this thesis was to create a method to predict portal dose images that was versatile and accurate enough to use in a clinical setting. All measured images in this work were obtained with an amorphous silicon electronic portal imaging device (a-Si EPID), but the technique is applicable to any planar imager. A detailed, physics-motivated fluence model was developed to characterize fluence exiting the linear accelerator head. The model was further refined using results from Monte Carlo simulations and schematics of the linear accelerator. The fluence incident on the EPID was converted to a portal dose image through a superposition of Monte Carlo-generated, monoenergetic dose kernels specific to the a-Si EPID. Predictions of clinical IMRT fields with no patient present agreed with measured portal dose images within 3% and 3 mm. The dose kernels were applied ignoring the geometrically divergent nature of incident fluence on the EPID. A computational investigation into this parallel dose kernel assumption determined its validity under clinically relevant situations. Introducing a patient or phantom into the beam required the portal image prediction algorithm to account for patient scatter and attenuation. Primary fluence was calculated by attenuating raylines cast through the patient CT dataset, while scatter fluence was determined through the superposition of pre-calculated scatter fluence kernels. Total dose in the EPID was calculated by convolving the total predicted incident fluence with the EPID-specific dose kernels. The algorithm was tested on water slabs with square fields, agreeing with measurement within 3% and 3 mm. The

  13. Personal health records as portal to the electronic medical record.

    PubMed

    Cahill, Jennifer E; Gilbert, Mark R; Armstrong, Terri S

    2014-03-01

    This topic review discusses the evolving clinical challenges associated with the implementation of electronic personal health records (PHR) that are fully integrated with electronic medical records (EMR). The benefits of facilitating patient access to the EMR through web-based, PHR-portals may be substantial; foremost is the potential to enhance the flow of information between patient and healthcare practitioner. The benefits of improved communication and transparency of care are presumed to be a reduction in clinical errors, increased quality of care, better patient-management of disease, and better disease and symptom comprehension. Yet PHR databases allow patients open access to newly-acquired clinical data without the benefit of concurrent expert clinical interpretation, and therefore may create the potential for greater patient distress and uncertainty. With specific attention to neuro-oncology patients, this review focuses on the developing conflicts and consequences associated with the use of a PHR that parallels data acquisition of the EMR in real-time. We conclude with a discussion of recommendations for implementing fully-integrated PHR for neuro-oncology patients.

  14. The wired patient: patterns of electronic patient portal use among patients with cardiac disease or diabetes.

    PubMed

    Jones, James Brian; Weiner, Jonathan P; Shah, Nirav R; Stewart, Walter F

    2015-02-20

    As providers develop an electronic health record-based infrastructure, patients are increasingly using Web portals to access their health information and participate electronically in the health care process. Little is known about how such portals are actually used. In this paper, our goal was to describe the types and patterns of portal users in an integrated delivery system. We analyzed 12 months of data from Web server log files on 2282 patients using a Web-based portal to their electronic health record (EHR). We obtained data for patients with cardiovascular disease and/or diabetes who had a Geisinger Clinic primary care provider and were registered "MyGeisinger" Web portal users. Hierarchical cluster analysis was applied to longitudinal data to profile users based on their frequency, intensity, and consistency of use. User types were characterized by basic demographic data from the EHR. We identified eight distinct portal user groups. The two largest groups (41.98%, 948/2258 and 24.84%, 561/2258) logged into the portal infrequently but had markedly different levels of engagement with their medical record. Other distinct groups were characterized by tracking biometric measures (10.54%, 238/2258), sending electronic messages to their provider (9.25%, 209/2258), preparing for an office visit (5.98%, 135/2258), and tracking laboratory results (4.16%, 94/2258). There are naturally occurring groups of EHR Web portal users within a population of adult primary care patients with chronic conditions. More than half of the patient cohort exhibited distinct patterns of portal use linked to key features. These patterns of portal access and interaction provide insight into opportunities for electronic patient engagement strategies.

  15. Study of a prototype high quantum efficiency thick scintillation crystal video-electronic portal imaging device.

    PubMed

    Samant, Sanjiv S; Gopal, Arun

    2006-08-01

    Image quality in portal imaging suffers significantly from the loss in contrast and spatial resolution that results from the excessive Compton scatter associated with megavoltage x rays. In addition, portal image quality is further reduced due to the poor quantum efficiency (QE) of current electronic portal imaging devices (EPIDs). Commercial video-camera-based EPIDs or VEPIDs that utilize a thin phosphor screen in conjunction with a metal buildup plate to convert the incident x rays to light suffer from reduced light production due to low QE (<2% for Eastman Kodak Lanex Fast-B). Flat-panel EPIDs that utilize the same luminescent screen along with an a-Si:H photodiode array provide improved image quality compared to VEPIDs, but they are expensive and can be susceptible to radiation damage to the peripheral electronics. In this article, we present a prototype VEPID system for high quality portal imaging at sub-monitor-unit (subMU) exposures based on a thick scintillation crystal (TSC) that acts as a high QE luminescent screen. The prototype TSC system utilizes a 12 mm thick transparent CsI(Tl) (thallium-activated cesium iodide) scintillator for QE=0.24, resulting in significantly higher light production compared to commercial phosphor screens. The 25 X 25 cm2 CsI(Tl) screen is coupled to a high spatial and contrast resolution Video-Optics plumbicon-tube camera system (1240 X 1024 pixels, 250 microm pixel width at isocenter, 12-bit ADC). As a proof-of-principle prototype, the TSC system with user-controlled camera target integration was adapted for use in an existing clinical gantry (Siemens BEAMVIEW(PLUS)) with the capability for online intratreatment fluoroscopy. Measurements of modulation transfer function (MTF) were conducted to characterize the TSC spatial resolution. The measured MTF along with measurements of the TSC noise power spectrum (NPS) were used to determine the system detective quantum efficiency (DQE). A theoretical expression of DQE(0) was developed

  16. Visualization of the herpes simplex virus portal in situ by cryo-electron tomography

    SciTech Connect

    Cardone, Giovanni; Winkler, Dennis C.; Trus, Benes L.

    2007-05-10

    Herpes simplex virus type 1 (HSV-1), the prototypical herpesvirus, has an icosahedral nucleocapsid surrounded by a proteinaceous tegument and a lipoprotein envelope. As in tailed bacteriophages, the icosahedral symmetry of the capsid is broken at one of the 12 vertices, which is occupied by a dodecameric ring of portal protein, UL6, instead of a pentamer of the capsid protein, UL19. The portal ring serves as a conduit for DNA entering and exiting the capsid. From a cryo-EM reconstruction of capsids immuno-gold-labeled with anti-UL6 antibodies, we confirmed that UL6 resides at a vertex. To visualize the portal in the context ofmore » the assembled capsid, we used cryo-electron tomography to determine the three-dimensional structures of individual A-capsids (empty, mature capsids). The similarity in size and overall shape of the portal and a UL19 pentamer - both are cylinders of {approx} 800 kDa - combined with residual noise in the tomograms, prevented us from identifying the portal vertices directly; however, this was accomplished by a computational classification procedure. Averaging the portal-containing subtomograms produced a structure that tallies with the isolated portal, as previously reconstructed by cryo-EM. The portal is mounted on the outer surface of the capsid floor layer, with its narrow end pointing outwards. This disposition differs from that of known phage portals in that the bulk of its mass lies outside, not inside, the floor. This distinction may be indicative of divergence at the level of portal-related functions other than its role as a DNA channel.« less

  17. The Impact of Electronic Patient Portals on Patient Care: A Systematic Review of Controlled Trials

    PubMed Central

    Ammenwerth, Elske; Schnell-Inderst, Petra

    2012-01-01

    Background Modern information technology is changing and provides new challenges to health care. The emergence of the Internet and the electronic health record (EHR) has brought new opportunities for patients to play a more active role in his/her care. Although in many countries patients have the right to access their clinical information, access to clinical records electronically is not common. Patient portals consist of provider-tethered applications that allow patients to electronically access health information that are documented and managed by a health care institution. Although patient portals are already being implemented, it is still unclear in which ways these technologies can influence patient care. Objective To systematically review the available evidence on the impact of electronic patient portals on patient care. Methods A systematic search was conducted using PubMed and other sources to identify controlled experimental or quasi-experimental studies on the impact of patient portals that were published between 1990 and 2011. A total of 1,306 references from all the publication hits were screened, and 13 papers were retrieved for full text analysis. Results We identified 5 papers presenting 4 distinct studies. There were no statistically significant changes between intervention and control group in the 2 randomized controlled trials investigating the effect of patient portals on health outcomes. Significant changes in the patient portal group, compared to a control group, could be observed for the following parameters: quicker decrease in office visit rates and slower increase in telephone contacts; increase in number of messages sent; changes of the medication regimen; and better adherence to treatment. Conclusions The number of available controlled studies with regard to patient portals is low. Even when patient portals are often discussed as a way to empower patients and improve quality of care, there is insufficient evidence to support this

  18. Use of an electronic patient portal among the chronically ill: an observational study.

    PubMed

    Riippa, Iiris; Linna, Miika; Rönkkö, Ilona; Kröger, Virpi

    2014-12-08

    Electronic patient portals may enhance effective interaction between the patient and the health care provider. To grasp the full potential of patient portals, health care providers need more knowledge on which patient groups prefer electronic services and how patients should be served through this channel. The objective of this study was to assess how chronically ill patients' state of health, comorbidities, and previous care are associated with their adoption and use of a patient portal. A total of 222 chronically ill patients, who were offered access to a patient portal with their health records and secure messaging with care professionals, were included in the study. Differences in the characteristics of non-users, viewers, and interactive users of the patient portal were analyzed before access to the portal. Patients' age, gender, diagnoses, levels of the relevant physiological measurements, health care contacts, and received physiological measurements were collected from the care provider's electronic health record. In addition, patient-reported health and patient activation were assessed by a survey. Despite the broad range of measures used to indicate the patients' state of health, the portal user groups differed only in their recorded diagnosis for hypertension, which was most common in the non-user group. However, there were significant differences in the amount of care received during the year before access to the portal. The non-user group had more nurse visits and more measurements of relevant physiological outcomes than viewers and interactive users. They also had fewer referrals to specialized care during the year before access to the portal than the two other groups. The viewers and the interactive users differed from each other significantly in the number of nurse calls received, the interactive users having more calls than the viewers. No significant differences in age, gender, or patient activation were detected between the user groups. Previous

  19. Electronic patient portals: evidence on health outcomes, satisfaction, efficiency, and attitudes: a systematic review.

    PubMed

    Goldzweig, Caroline Lubick; Orshansky, Greg; Paige, Neil M; Towfigh, Ali Alexander; Haggstrom, David A; Miake-Lye, Isomi; Beroes, Jessica M; Shekelle, Paul G

    2013-11-19

    Patient portals tied to provider electronic health record (EHR) systems are increasingly popular. To systematically review the literature reporting the effect of patient portals on clinical care. PubMed and Web of Science searches from 1 January 1990 to 24 January 2013. Hypothesis-testing or quantitative studies of patient portals tethered to a provider EHR that addressed patient outcomes, satisfaction, adherence, efficiency, utilization, attitudes, and patient characteristics, as well as qualitative studies of barriers or facilitators, were included. Two reviewers independently extracted data and addressed discrepancies through consensus discussion. From 6508 titles, 14 randomized, controlled trials; 21 observational, hypothesis-testing studies; 5 quantitative, descriptive studies; and 6 qualitative studies were included. Evidence is mixed about the effect of portals on patient outcomes and satisfaction, although they may be more effective when used with case management. The effect of portals on utilization and efficiency is unclear, although patient race and ethnicity, education level or literacy, and degree of comorbid conditions may influence use. Limited data for most outcomes and an absence of reporting on organizational and provider context and implementation processes. Evidence that patient portals improve health outcomes, cost, or utilization is insufficient. Patient attitudes are generally positive, but more widespread use may require efforts to overcome racial, ethnic, and literacy barriers. Portals represent a new technology with benefits that are still unclear. Better understanding requires studies that include details about context, implementation factors, and cost.

  20. TOPICAL REVIEW: Electronic portal imaging devices: a review and historical perspective of contemporary technologies and research

    NASA Astrophysics Data System (ADS)

    Antonuk, Larry E.

    2002-03-01

    A review of electronic portal imaging devices (EPIDs) used in external beam, megavoltage radiation therapy is presented. The review consists of a brief introduction to the definition, role and clinical significance of portal imaging, along with a discussion of radiotherapy film systems and the motivations for EPIDs. This is followed by a summary of the challenges and constraints inherent to portal imaging along with a concise, historical review of the technologies that have been explored and developed. The paper then examines, in greater depth, the two first-generation technologies that have found widespread clinical use starting from the late 1980s. This is followed by a broad overview of the physics, operation, properties and advantages of active matrix, flat-panel, megavoltage imagers, presently being commercially introduced to clinical environments or expected to be introduced in the future. Finally, a survey of contemporary research efforts focused on improving portal imaging performance by addressing various weaknesses in existing commercial systems is presented.

  1. Patient Use of the Electronic Communication Portal in Management of Type 2 Diabetes.

    PubMed

    Peremislov, Diana

    2017-09-01

    High incidence and prevalence of type 2 diabetes require urgent attention to the management of this chronic disease. The purpose of this study was to explore electronic communication (e-communication) between patients with type 2 diabetes and their providers within the patient portal. Qualitative design with conventional content analysis techniques was used. A purposive random sample of 90 electronic medical record charts of patient-portal users with type 2 diabetes was subjected to a retrospective review. The sample mainly consisted of patients between the ages of 50 and 70 years, who were white, non-Hispanic, and English-speaking. The three major themes that emerged in e-communication via patient portal were inform theme, which was the most frequently identified theme; instruct/request theme, which was mainly used in initiation of e-communication; and the question theme. The patient portal was used primarily for requests by patients and instruction by providers, showing relatively short e-message encounters with a high number of partially completed encounters, frequent lack of resolution, and a low level of involvement of diabetes specialists in e-communication. There is a need to revise healthcare system guidelines on initiation and use of e-communication via patient portal and develop standardized templates to promote diabetes education in type 2 diabetes.

  2. Dosimetric Verification of IMRT Treatment Plans Using an Electronic Portal Imaging Device

    SciTech Connect

    Kruszyna, Marta

    This paper presents the procedures and results of dosimetric verification using an Electronic Portal Imaging Device as a tool for pre-treatment dosimetry in IMRT technique at the Greater Poland Cancer Centre in Poznan, Poland. The evaluation of dosimetric verification for various organ, during a 2 year period is given.

  3. Liquid-phase explosive crystallization of electron-beam-evaporated a-Si films induced by flash lamp annealing

    NASA Astrophysics Data System (ADS)

    Ohdaira, Keisuke; Matsumura, Hideki

    2013-01-01

    We succeed in the formation of micrometer-order-thick polycrystalline silicon (poly-Si) films through the flash-lamp-induced liquid-phase explosive crystallization (EC) of precursor a-Si films prepared by electron-beam (EB) evaporation. The velocity of the explosive crystallization (vEC) is estimated to be ˜14 m/s, which is close to the velocity of the liquid-phase epitaxy (LPE) of Si at a temperature around the melting point of a-Si of 1418 K. Poly-Si films formed have micrometer-order-long grains stretched along a lateral crystallization direction, and X-ray diffraction (XRD) and electron diffraction pattern measurements reveal that grains in poly-Si films tend to have a particular orientation. These features are significantly different from our previous results: the formation of poly-Si films containing randomly-oriented 10-nm-sized fine grains formed from a-Si films prepared by catalytic chemical vapor deposition (Cat-CVD) or sputtering. One possible reason for the emergence of a different EC mode in EB-evaporated a-Si films is the suppression of solid-phase nucleation (SPN) during Flash Lamp Annealing (FLA) due to tensile stress which precursor a-Si films originally hold. Poly-Si films formed from EB-evaporated a-Si films would contribute to the realization of high-efficiency thin-film poly-Si solar cells because of large and oriented grains.

  4. HPB Online: an electronic health education portal in Singapore.

    PubMed

    Vijaya, K; Chan, S P; Ho, H P C; Lim, Y Y L; Lim, R

    2006-01-01

    In 2001, the Health Promotion Board (HPB) developed HPB Online, an internet-based health education portal to disseminate health messages. The objective of this article is to describe the structure of HPB Online, review its reach as a tool to deliver health information in Singapore, and discuss the advantages of using the internet to complement traditional media such as the television, newspapers and radio. Since its inception in 2001, the numbers of page-views, monthly visits and repeat visitors have increased markedly. The most popular webpages have consistently been Food Info Search. The average length of visit also showed a gradual increase during the study period, from about 11.0 minutes in January 2002 to 18.5 minutes in December 2004. The key advantage of using the HPB Online is that it allows quick delivery of information to the public and this is ideal for time-sensitive issues. It helps Singaporeans to make better informed decisions to maintain and to improve their health. With its high utilisation, the HPB will continue to use the internet as part of its multichannel marketing strategy to disseminate health information.

  5. Electronic Health Record Patient Portal Adoption by Health Care Consumers: An Acceptance Model and Survey.

    PubMed

    Tavares, Jorge; Oliveira, Tiago

    2016-03-02

    The future of health care delivery is becoming more citizen centered, as today's user is more active, better informed, and more demanding. Worldwide governments are promoting online health services, such as electronic health record (EHR) patient portals and, as a result, the deployment and use of these services. Overall, this makes the adoption of patient-accessible EHR portals an important field to study and understand. The aim of this study is to understand the factors that drive individuals to adopt EHR portals. We applied a new adoption model using, as a starting point, Ventkatesh's Unified Theory of Acceptance and Use of Technology in a consumer context (UTAUT2) by integrating a new construct specific to health care, a new moderator, and new relationships. To test the research model, we used the partial least squares (PLS) causal modelling approach. An online questionnaire was administrated. We collected 360 valid responses. The statistically significant drivers of behavioral intention are performance expectancy (beta=.200; t=3.619), effort expectancy (beta=.185; t=2.907), habit (beta=.388; t=7.320), and self-perception (beta=.098; t=2.285). The predictors of use behavior are habit (beta=0.206; t=2.752) and behavioral intention (beta=0.258; t=4.036). The model explained 49.7% of the variance in behavioral intention and 26.8% of the variance in use behavior. Our research helps to understand the desired technology characteristics of EHR portals. By testing an information technology acceptance model, we are able to determine what is more valued by patients when it comes to deciding whether to adopt EHR portals or not. The inclusion of specific constructs and relationships related to the health care consumer area also had a significant impact on understanding the adoption of EHR portals.

  6. Electronic Health Record Patient Portal Adoption by Health Care Consumers: An Acceptance Model and Survey

    PubMed Central

    2016-01-01

    Background The future of health care delivery is becoming more citizen centered, as today’s user is more active, better informed, and more demanding. Worldwide governments are promoting online health services, such as electronic health record (EHR) patient portals and, as a result, the deployment and use of these services. Overall, this makes the adoption of patient-accessible EHR portals an important field to study and understand. Objective The aim of this study is to understand the factors that drive individuals to adopt EHR portals. Methods We applied a new adoption model using, as a starting point, Ventkatesh's Unified Theory of Acceptance and Use of Technology in a consumer context (UTAUT2) by integrating a new construct specific to health care, a new moderator, and new relationships. To test the research model, we used the partial least squares (PLS) causal modelling approach. An online questionnaire was administrated. We collected 360 valid responses. Results The statistically significant drivers of behavioral intention are performance expectancy (beta=.200; t=3.619), effort expectancy (beta=.185; t=2.907), habit (beta=.388; t=7.320), and self-perception (beta=.098; t=2.285). The predictors of use behavior are habit (beta=0.206; t=2.752) and behavioral intention (beta=0.258; t=4.036). The model explained 49.7% of the variance in behavioral intention and 26.8% of the variance in use behavior. Conclusions Our research helps to understand the desired technology characteristics of EHR portals. By testing an information technology acceptance model, we are able to determine what is more valued by patients when it comes to deciding whether to adopt EHR portals or not. The inclusion of specific constructs and relationships related to the health care consumer area also had a significant impact on understanding the adoption of EHR portals. PMID:26935646

  7. Maternity patients' access to their electronic medical records: use and perspectives of a patient portal.

    PubMed

    Megan Forster, Megan; Dennison, Kerrie; Callen, Joanne; Andrew, Andrew; Westbrook, Johanna I

    Patients have been able to access clinical information from their paper-based health records for a number of years. With the advent of Electronic Medical Records (EMRs) access to this information can now be achieved online using a secure electronic patient portal. The purpose of this study was to investigate maternity patients' use and perceptions of a patient portal developed at the Mater Mothers' Hospital in Brisbane, Australia. A web-based patient portal, one of the first developed and deployed in Australia, was introduced on 26 June 2012. The portal was designed for maternity patients booked at Mater Mothers' Hospital, as an alternative to the paper-based Pregnancy Health Record. Through the portal, maternity patients are able to complete their hospital registration form online and obtain current health information about their pregnancy (via their EMR), as well as access a variety of support tools to use during their pregnancy such as tailored public health advice. A retrospective cross-sectional study design was employed. Usage statistics were extracted from the system for a one year period (1 July 2012 to 30 June 2013). Patients' perceptions of the portal were obtained using an online survey, accessible by maternity patients for two weeks in February 2013 (n=80). Descriptive statistics were employed to analyse the data. Between July 2012 and June 2013, 10,892 maternity patients were offered a patient portal account and access to their EMR. Of those 6,518 created one (60%; 6,518/10,892) and 3,104 went on to request access to their EMR (48%; 3,104/6,518). Of these, 1,751 had their access application granted by 30 June 2013. The majority of maternity patients submitted registration forms online via the patient portal (56.7%). Patients could view their EMR multiple times: there were 671 views of the EMR, 2,781 views of appointment schedules and 135 birth preferences submitted via the EMR. Eighty survey responses were received from EMR account holders, (response

  8. The stability of liquid-filled matrix ionization chamber electronic portal imaging devices for dosimetry purposes.

    PubMed

    Louwe, R J W; Tielenburg, R; van Ingen, K M; Mijnheer, B J; van Herk, M B

    2004-04-01

    This study was performed to determine the stability of liquid-filled matrix ionization chamber (LiFi-type) electronic portal imaging devices (EPID) for dosimetric purposes. The short- and long-term stability of the response was investigated, as well as the importance of factors influencing the response (e.g., temperature fluctuations, radiation damage, and the performance of the electronic hardware). It was shown that testing the performance of the electronic hardware as well as the short-term stability of the imagers may reveal the cause of a poor long-term stability of the imager response. In addition, the short-term stability was measured to verify the validity of the fitted dose-response curve immediately after beam startup. The long-term stability of these imagers could be considerably improved by correcting for room temperature fluctuations and gradual changes in response due to radiation damage. As a result, the reproducibility was better than 1% (1 SD) over a period of two years. The results of this study were used to formulate recommendations for a quality control program for portal dosimetry. The effect of such a program was assessed by comparing the results of portal dosimetry and in vivo dosimetry using diodes during the treatment of 31 prostate patients. The improvement of the results for portal dosimetry was consistent with the deviations observed with the reproducibility tests in that particular period. After a correction for the variation in response of the imager, the average difference between the measured and prescribed dose during the treatment of prostate patients was -0.7%+/-1.5% (1 SD), and -0.6%+/-1.1% (1 SD) for EPID and diode in vivo dosimetry, respectively. It can be concluded that a high stability of the response can be achieved for this type of EPID by applying a rigorous quality control program.

  9. Implementation of an integrated preoperative care pathway and regional electronic clinical portal for preoperative assessment.

    PubMed

    Bouamrane, Matt-Mouley; Mair, Frances S

    2014-11-19

    Effective surgical pre-assessment will depend upon the collection of relevant medical information, good data management and communication between the members of the preoperative multi-disciplinary team. NHS Greater Glasgow and Clyde has implemented an electronic preoperative integrated care pathway (eForm) allowing all hospitals to access a comprehensive patient medical history via a clinical portal on the health-board intranet. We conducted six face-to-face semi-structured interviews and participated in one focus group and two workshops with key stakeholders involved in the Planned Care Improvement (PCIP) and Electronic Patient Record programmes. We used qualitative methods and Normalisation Process Theory in order to identify the key factors which led to the successful deployment of the preoperative eForm in the health-board. In January 2013, more than 90,000 patient preoperative assessments had been completed via the electronic portal. Two complementary strategic efforts were instrumental in the successful deployment of the preoperative eForm. At the local health-board level: the PCIP led to the rationalisation of surgical pre-assessment clinics and the standardisation of preoperative processes. At the national level: the eHealth programme selected portal technology as an iterative strategic technology solution towards a virtual electronic patient record. Our study has highlighted clear synergies between these two standardisation efforts. The adoption of the eForm into routine preoperative work practices can be attributed to: (i) a policy context - including performance targets - promoting the rationalisation of surgical pre-assessment pathways, (ii) financial and organisational resources to support service redesign and the use of information technology for operationalising the standardisation of preoperative processes, (iii) a sustained engagement with stakeholders throughout the iterative phases of the preoperative clinics redesign, guidelines standardisation

  10. Validation of a Novel Electronic Health Record Patient Portal Advance Care Planning Delivery System.

    PubMed

    Bose-Brill, Seuli; Feeney, Michelle; Prater, Laura; Miles, Laura; Corbett, Angela; Koesters, Stephen

    2018-06-26

    Advance care planning allows patients to articulate their future care preferences should they no longer be able to make decisions on their own. Early advance care planning in outpatient settings provides benefits such as less aggressive care and fewer hospitalizations, yet it is underutilized due to barriers such as provider time constraints and communication complexity. Novel methods, such as patient portals, provide a unique opportunity to conduct advance care planning previsit planning for outpatient care. This follow-up to our pilot study aimed to conduct pragmatic testing of a novel electronic health record-tethered framework and its effects on advance care planning delivery in a real-world primary care setting. Our intervention tested a previsit advance care planning workflow centered around a framework sent via secure electronic health record-linked patient portal in a real-world clinical setting. The primary objective of this study was to determine its impact on frequency and quality of advance care planning documentation. We conducted a pragmatic trial including 2 sister clinical sites, one site implementing the intervention and the other continuing standard care. A total of 419 patients aged between 50 and 93 years with active portal accounts received intervention (n=200) or standard care (n=219). Chart review analyzed the presence of advance care planning and its quality and was graded with previously established scoring criteria based on advance care planning best practice guidelines from multiple nations. A total of 19.5% (39/200) of patients who received previsit planning responded to the framework. We found that the intervention site had statistically significant improvement in new advance care planning documentation rates (P<.01) and quality (P<.01) among all eligible patients. Advance care planning documentation rates increased by 105% (19/39 to 39/39) and quality improved among all patients who engaged in the previsit planning framework (n=39

  11. Role of interface states on electron transport in a-Si:H/nc-Si:H multilayer structures

    NASA Astrophysics Data System (ADS)

    Yadav, Asha; Kumari, Juhi; Agarwal, Pratima

    2018-05-01

    In this paper we report, I-V characteristic of a-Si:H/nc-Si:H multilayer structures in lateral as well as transverse direction. In lateral geometry, where the interfaces are parallel to the direction of electronic transport, residual photo conductivity (persistent photoconductivity) is observed after the light was turned off. On the other hand, in transverse geometry, where interfaces are along the direction of electronic transport, the space charge limited currents are affected and higher density of states is obtained. The PPC was more in the structures where numbers of such interface were more. These results have been understood in terms of the charge carriers trapped at the interface, which influence the electronic transport.

  12. Preferences of Current and Potential Patients and Family Members Regarding Implementation of Electronic Communication Portals in Intensive Care Units.

    PubMed

    Brown, Samuel M; Bell, Sigall K; Roche, Stephanie D; Dente, Erica; Mueller, Ariel; Kim, Tae-Eun; O'Reilly, Kristin; Lee, Barbara Sarnoff; Sands, Ken; Talmor, Daniel

    2016-03-01

    The quality of communication with patients and family members in intensive care units (ICUs) is a focus of current interest for clinical care improvement. Electronic communication portals are commonly used in other healthcare settings to improve communication. We do not know whether patients and family members desire such portals in ICUs, and if so, what functionality they should provide. To define interest in and desired elements of an electronic communication portal among current and potential ICU patients and their family members. We surveyed, via an Internet panel, 1,050 English-speaking adults residing in the United States with a personal or family history of an ICU admission within 10 years (cohort A) and 1,050 individuals without a history of such admission (cohort B). We also administered a survey instrument in person to 105 family members of patients currently admitted to ICUs at an academic medical center in Boston (cohort C). Respondents, especially current ICU family members, supported an electronic communication portal, including access via an electronic tablet. They wanted at least daily updates, one-paragraph summaries of family meetings including a list of key decisions made, and knowledge of the role and experience of treating clinicians. Overall, they preferred detailed rather than "big picture" information. Respondents were generally comfortable sharing information with their family members. Preferences regarding a communication portal varied significantly by age, sex, ethnicity, and prior experience with ICU hospitalization. Electronic communication portals appear welcome in contemporary ICUs. Frequent updates, knowledge about the professional qualifications of clinicians, detailed medical information, and documentation of family meetings are particularly desired.

  13. Impact and User Satisfaction of a Clinical Information Portal Embedded in an Electronic Health Record

    PubMed Central

    Tannery, Nancy H; Epstein, Barbara A; Wessel, Charles B; Yarger, Frances; LaDue, John; Klem, Mary Lou

    2011-01-01

    In 2008, a clinical information tool was developed and embedded in the electronic health record system of an academic medical center. In 2009, the initial information tool, Clinical-e, was superseded by a portal called Clinical Focus, with a single search box enabling a federated search of selected online information resources. To measure the usefulness and impact of Clinical Focus, a survey was used to gather feedback about users' experience with this clinical resource. The survey determined what type of clinicians were using this tool and assessed user satisfaction and perceived impact on patient care decision making. Initial survey results suggest the majority of respondents found Clinical Focus easy to navigate, the content easy to read, and the retrieved information relevant and complete. The majority would recommend Clinical Focus to their colleagues. Results indicate that this tool is a promising area for future development. PMID:22016670

  14. Selective scanning tunnelling microscope electron-induced reactions of single biphenyl molecules on a Si(100) surface.

    PubMed

    Riedel, Damien; Bocquet, Marie-Laure; Lesnard, Hervé; Lastapis, Mathieu; Lorente, Nicolas; Sonnet, Philippe; Dujardin, Gérald

    2009-06-03

    Selective electron-induced reactions of individual biphenyl molecules adsorbed in their weakly chemisorbed configuration on a Si(100) surface are investigated by using the tip of a low-temperature (5 K) scanning tunnelling microscope (STM) as an atomic size source of electrons. Selected types of molecular reactions are produced, depending on the polarity of the surface voltage during STM excitation. At negative surface voltages, the biphenyl molecule diffuses across the surface in its weakly chemisorbed configuration. At positive surface voltages, different types of molecular reactions are activated, which involve the change of adsorption configuration from the weakly chemisorbed to the strongly chemisorbed bistable and quadristable configurations. Calculated reaction pathways of the molecular reactions on the silicon surface, using the nudge elastic band method, provide evidence that the observed selectivity as a function of the surface voltage polarity cannot be ascribed to different activation energies. These results, together with the measured threshold surface voltages and the calculated molecular electronic structures via density functional theory, suggest that the electron-induced molecular reactions are driven by selective electron detachment (oxidation) or attachment (reduction) processes.

  15. The Patient Portal of the Personal Cross-Enterprise Electronic Health Record (PEHR) in the Rhine-Neckar-Region.

    PubMed

    Brandner, Antje; Schreiweis, Björn; Aguduri, Lakshmi S; Bronsch, Tobias; Kunz, Aline; Pensold, Peter; Stein, Katharina E; Weiss, Nicolas; Yüksekogul, Nilay; Bergh, Björn; Heinze, Oliver

    2016-01-01

    Over the last years we stepwise implemented our vision of a personal cross-enterprise electronic health record (PEHR) in the Rhine-Neckar-Region in Germany. The patient portal is one part of the PEHR architecture with IHE connectivity. The patient is enabled to access and manage his medical record by use of the patient portal. Moreover, he can give his consent regarding which healthcare providers are allowed to send data into or read data from his medical record. Forthcoming studies will give evidence for improvements and further requirements to develop.

  16. The Advent of Portals.

    ERIC Educational Resources Information Center

    Jackson, Mary E.

    2002-01-01

    Explains portals as tools that gather a variety of electronic information resources, including local library resources, into a single Web page. Highlights include cross-database searching; integration with university portals and course management software; the ARL (Association of Research Libraries) Scholars Portal Initiative; and selected vendors…

  17. A comparative evaluation of two head and neck immobilization devices using electronic portal imaging.

    PubMed

    Donato, K; Leszczynski, K; Fleming, K

    2006-02-01

    A study was performed to compare the positioning reproducibility and the cost efficiency for two head and neck immobilization devices: the Uvex (Uvex Safety, Smithfield, USA) plastic mask system and the Finesse Frame with Ultraplast System (PLANET Medical, Svendborg, Denmark). 20 patients treated with 3D conformal radiation therapy for head and neck cancers were randomly selected (10 for each of the two different immobilization systems) and electronic portal images acquired during their course of treatment were saved and used in this study. The anatomical landmark coordinates and their shifts in the anteroposterior (AP) and craniocaudal (CC) directions with respect to the digitized simulator films for lateral fields were analysed using an in-house developed portal image registration system. Statistically, no evidence was found to indicate that the systematic components of the displacement for the Uvex system and the Finesse Frame with Ultraplast System were different from each other or from zero. The random component of displacement was slightly smaller in the AP direction for the Uvex than the Ultraplast system (sigma = 1.9 mm and 2.9 mm, respectively, p = 0.007), but larger in the CC direction (sigma = 3.8 mm and 2.2 mm, respectively, p<10(-9)). Production time and required materials for a radiation therapy department were also quantified to assess costs for each system. The overall costs per patient were estimated at 141.50 dollars (CAD) and 82.10 dollars for the Uvex and Ultraplast systems, respectively. The Finesse Frame with Ultraplast System of immobilization for head and neck cancer treatment provides a field placement reproducibility that is equal to, or greater than, that of the Uvex plastic mask immobilization system and, while it requires more expensive materials, the workload and consequently overall cost is greatly reduced.

  18. Facilitators and Barriers of Electronic Health Record Patient Portal Adoption by Older Adults: A Literature Study.

    PubMed

    Wildenbos, Gaby Anne; Peute, Linda; Jaspers, Monique

    2017-01-01

    Patient portal usage by older adults, patients aged 50 years old and above, is intended to improve their access and quality of care. Acceptance of patient portals by this target group is low. This paper discusses the results of a literature review to determine the facilitators and barriers that drive or inhibit older patients to adopt patient portals. Articles were included when they described an acceptance, adoption or usability evaluation study of a patient portal. From a total of 245 potentially relevant articles, 8 articles were finally included. We used the Unified Theory of Acceptance and Use of Technology (UTAUT) as a classification model to analyze factors influencing older adults' acceptance of patient portals. Main facilitators for acceptance were 'performance expectancy' and 'voluntariness of use' related to a higher level of education and experienced health. Main barriers were limited health literacy and motivation related to involuntariness to use a patient portal. Poor facilitation conditions (limited technology access and no prior knowledge on existence of a patient portal) hampered access to a portal. More thorough insight into the latter is needed to improve the reach and effectiveness of patient portals among older patients.

  19. NOTE: A method for controlling image acquisition in electronic portal imaging devices

    NASA Astrophysics Data System (ADS)

    Glendinning, A. G.; Hunt, S. G.; Bonnett, D. E.

    2001-02-01

    Certain types of camera-based electronic portal imaging devices (EPIDs) which initiate image acquisition based on sensing a change in video level have been observed to trigger unreliably at the beginning of dynamic multileaf collimation sequences. A simple, novel means of controlling image acquisition with an Elekta linear accelerator (Elekta Oncology Systems, Crawley, UK) is proposed which is based on illumination of a photodetector (ORP-12, Silonex Inc., Plattsburgh, NY, USA) by the electron gun of the accelerator. By incorporating a simple trigger circuit it is possible to derive a beam on/off status signal which changes at least 100 ms before any dose is measured by the accelerator. The status signal does not return to the beam-off state until all dose has been delivered and is suitable for accelerator pulse repetition frequencies of 50-400 Hz. The status signal is thus a reliable means of indicating the initiation and termination of radiation exposure, and thus controlling image acquisition of such EPIDs for this application.

  20. Clinician Perspectives on an Electronic Portal to Improve Communication with Patients and Families in the Intensive Care Unit.

    PubMed

    Bell, Sigall K; Roche, Stephanie D; Johansson, Anna C; O'Reilly, Kristin P; Lee, Barbara S; Sands, Kenneth E; Talmor, Daniel S; Brown, Samuel M

    2016-12-01

    Communication in the intensive care unit (ICU) often falls short of patient and family needs, putting them at risk for significant physical and emotional harm. As electronic patient portals rapidly evolve, one designed specifically for the ICU might potentially enhance communication among patients, family members, and clinicians; however, the views of frontline ICU staff on such technology are unknown. To identify clinician perspectives on the current state of communication among patients, families, and clinicians in the ICU, and assess their views on whether and how an electronic portal may address existing communication deficits and improve care. Three focus groups comprised altogether of 26 clinicians from 6 ICUs, representing several disciplines in an academic medical center in Boston, Massachusetts. Transcripts were analyzed inductively for major themes using grounded theory. We identified seven themes reflecting clinician perspectives on communication challenges and desired portal functionality: (1) comprehension and literacy; (2) results and updates; (3) patient and family preferences; (4) interclinician communication; (5) family informational needs; (6) the ICU as an unfamiliar environment; and (7) enhancing humanism through technology. Each theme included current gaps in practice, potential benefits and concerns related to an ICU communication portal, and participant recommendations. Benefits included enhanced education, patient/family engagement, and clinician workflow. Challenges included the stress and uncertainty of ICU care, fear of technology replacing human connection, existing interclinician communication failures, and the tension between informing families without overwhelming them. Overall, clinicians were cautiously supportive of an electronic portal to enhance communication in the ICU and made several specific recommendations for design and implementation. As new technologies expand opportunities for greater transparency and participation in

  1. SU-E-T-781: Using An Electronic Portal Imaging Device (EPID) for Correlating Linac Photon Beam Energies

    SciTech Connect

    Yaddanapudi, S; Cai, B; Sun, B

    2015-06-15

    Purpose: Electronic portal imaging devices (EPIDs) have proven to be useful for measuring several parameters of interest in linear accelerator (linac) quality assurance (QA). The purpose of this project was to evaluate the feasibility of using EPIDs for determining linac photon beam energies. Methods: Two non-clinical Varian TrueBeam linacs (Varian Medical Systems, Palo Alto, CA) with 6MV and 10MV photon beams were used to perform the measurements. The linacs were equipped with an amorphous silicon based EPIDs (aSi1000) that were used for the measurements. We compared the use of flatness versus percent depth dose (PDD) for predicting changes in linacmore » photon beam energy. PDD was measured in 1D water tank (Sun Nuclear Corporation, Melbourne FL) and the profiles were measured using 2D ion-chamber array (IC-Profiler, Sun Nuclear) and the EPID. Energy changes were accomplished by varying the bending magnet current (BMC). The evaluated energies conformed with the AAPM TG142 tolerance of ±1% change in PDD. Results: BMC changes correlating with a ±1% change in PDD corresponded with a change in flatness of ∼1% to 2% from baseline values on the EPID. IC Profiler flatness values had the same correlation. We observed a similar trend for the 10MV beam energy changes. Our measurements indicated a strong correlation between changes in linac photon beam energy and changes in flatness. For all machines and energies, beam energy changes produced change in the uniformity (AAPM TG-142), varying from ∼1% to 2.5%. Conclusions: EPID image analysis of beam profiles can be used to determine linac photon beam energy changes. Flatness-based metrics or uniformity as defined by AAPM TG-142 were found to be more sensitive to linac photon beam energy changes than PDD. Research funding provided by Varian Medical Systems. Dr. Sasa Mutic receives compensation for providing patient safety training services from Varian Medical Systems, the sponsor of this study.« less

  2. A Si IV/O IV Electron Density Diagnostic for the Analysis of IRIS Solar Spectra

    NASA Astrophysics Data System (ADS)

    Young, P. R.; Keenan, F. P.; Milligan, R. O.; Peter, H.

    2018-04-01

    Solar spectra of ultraviolet bursts and flare ribbons from the Interface Region Imaging Spectrograph (IRIS) have suggested high electron densities of > {10}12 cm‑3 at transition region temperatures of 0.1 MK, based on large intensity ratios of Si IV λ1402.77 to O IV λ1401.16. In this work, a rare observation of the weak O IV λ1343.51 line is reported from an X-class flare that peaked at 21:41 UT on 2014 October 24. This line is used to develop a theoretical prediction of the Si IV λ1402.77 to O IV λ1401.16 ratio as a function of density that is recommended to be used in the high-density regime. The method makes use of new pressure-dependent ionization fractions that take account of the suppression of dielectronic recombination at high densities. It is applied to two sequences of flare kernel observations from the October 24 flare. The first shows densities that vary between 3× {10}12 and 3× {10}13 cm‑3 over a seven-minute period, while the second location shows stable density values of around 2× {10}12 cm‑3 over a three-minute period.

  3. Automated detection of a prostate Ni-Ti stent in electronic portal images.

    PubMed

    Carl, Jesper; Nielsen, Henning; Nielsen, Jane; Lund, Bente; Larsen, Erik Hoejkjaer

    2006-12-01

    Planning target volumes (PTV) in fractionated radiotherapy still have to be outlined with wide margins to the clinical target volume due to uncertainties arising from daily shift of the prostate position. A recently proposed new method of visualization of the prostate is based on insertion of a thermo-expandable Ni-Ti stent. The current study proposes a new detection algorithm for automated detection of the Ni-Ti stent in electronic portal images. The algorithm is based on the Ni-Ti stent having a cylindrical shape with a fixed diameter, which was used as the basis for an automated detection algorithm. The automated method uses enhancement of lines combined with a grayscale morphology operation that looks for enhanced pixels separated with a distance similar to the diameter of the stent. The images in this study are all from prostate cancer patients treated with radiotherapy in a previous study. Images of a stent inserted in a humanoid phantom demonstrated a localization accuracy of 0.4-0.7 mm which equals the pixel size in the image. The automated detection of the stent was compared to manual detection in 71 pairs of orthogonal images taken in nine patients. The algorithm was successful in 67 of 71 pairs of images. The method is fast, has a high success rate, good accuracy, and has a potential for unsupervised localization of the prostate before radiotherapy, which would enable automated repositioning before treatment and allow for the use of very tight PTV margins.

  4. Walter Reed Army Medical Center's Internet-based electronic health portal.

    PubMed

    Abbott, Kevin C; Boocks, Carl E; Sun, Zhengyi; Boal, Thomas R; Poropatich, Ronald K

    2003-12-01

    Use of the World Wide Web (WWW) and electronic media to facilitate medical care has been the subject of many reports in the popular press. However, few reports have documented the results of implementing electronic health portals for essential medical tasks, such as prescription refills and appointments. At Walter Reed Army Medical Center, "Search & Learn" medical information, Internet-based prescription refills and patient appointments were established in January 2001. A multiphase retrospective analysis was conducted to determine the use of the "Search & Learn" medical information and the relative number of prescription refills and appointments conducted via the WWW compared with conventional methods. From January 2001 to May 2002, there were 34,741 refills and 819 appointments made over the Internet compared with 2,275,112 refills and approximately 500,000 appointments made conventionally. WWW activity accounted for 1.52% of refills and 0.16% of appointments. There was a steady increase in this percentage over the time of the analysis. In April of 2002, the monthly average of online refills had risen to 4.57% and online appointments were at 0.27%. Online refills were projected to account for 10% of all prescriptions in 2 years. The "Search & Learn" medical information portion of our web site received 147,429 unique visits during this same time frame, which was an average of 326 visitors per day. WWW-based methods of conducting essential medical tasks accounted for a small but rapidly increasing percentage of total activity at Walter Reed Army Medical Center. Subsequent phases of analysis will assess demographic and geographic factors and aid in the design of future systems to increase use of the Internet-based systems.

  5. Online patient websites for electronic health record access among vulnerable populations: portals to nowhere?

    PubMed

    Tieu, Lina; Schillinger, Dean; Sarkar, Urmimala; Hoskote, Mekhala; Hahn, Kenneth J; Ratanawongsa, Neda; Ralston, James D; Lyles, Courtney R

    2017-04-01

    With the rapid rise in the adoption of patient portals, many patients are gaining access to their personal health information online for the first time. The objective of this study was to examine specific usability barriers to patient portal engagement among a diverse group of patients and caregivers. We conducted interviews using performance testing and think-aloud methods with 23 patients and 2 caregivers as they first attempted to use features of a newly launched patient portal. In navigating the portal, participants experienced basic computer barriers (eg, difficulty using a mouse), routine computer barriers (eg, mistyping, navigation issues), reading/writing barriers, and medical content barriers. Compared to participants with adequate health literacy, participants with limited health literacy required 2 additional minutes to complete each task and were more likely to experience each type of navigational barrier. They also experienced more inaccuracies in interpreting a test result and finding a treatment plan within an after-visit summary. When using a patient portal for the first time, participants with limited health literacy completed fewer tasks unassisted, had a higher prevalence of encountering barriers, took longer to complete tasks, and had more problems accurately interpreting medical information. Our findings suggest a strong need for tailored and accessible training and support to assist all vulnerable patients and/or caregivers with portal registration and use. Measuring the health literacy of a patient population might serve as a strong proxy for identifying patients who need the most support in using health technologies. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  6. Quantitative measurement of MLC leaf displacements using an electronic portal image device

    NASA Astrophysics Data System (ADS)

    Yang, Yong; Xing, Lei

    2004-04-01

    The success of an IMRT treatment relies on the positioning accuracy of the MLC (multileaf collimator) leaves for both step-and-shoot and dynamic deliveries. In practice, however, there exists no effective and quantitative means for routine MLC QA and this has become one of the bottleneck problems in IMRT implementation. In this work we present an electronic portal image device (EPID) based method for fast and accurate measurement of MLC leaf positions at arbitrary locations within the 40 cm × 40 cm radiation field. The new technique utilizes the fact that the integral signal in a small region of interest (ROI) is a sensitive and reliable indicator of the leaf displacement. In this approach, the integral signal at a ROI was expressed as a weighted sum of the contributions from the displacements of the leaf above the point and the adjacent leaves. The weighting factors or linear coefficients of the system equations were determined by fitting the integral signal data for a group of pre-designed MLC leaf sequences to the known leaf displacements that were intentionally introduced during the creation of the leaf sequences. Once the calibration is done, the system can be used for routine MLC leaf positioning QA to detect possible leaf errors. A series of tests was carried out to examine the functionality and accuracy of the technique. Our results show that the proposed technique is potentially superior to the conventional edge-detecting approach in two aspects: (i) it deals with the problem in a systematic approach and allows us to take into account the influence of the adjacent MLC leaves effectively; and (ii) it may improve the signal-to-noise ratio and is thus capable of quantitatively measuring extremely small leaf positional displacements. Our results indicate that the technique can detect a leaf positional error as small as 0.1 mm at an arbitrary point within the field in the absence of EPID set-up error and 0.3 mm when the uncertainty is considered. Given its

  7. A Monte Carlo calculation model of electronic portal imaging device for transit dosimetry through heterogeneous media

    SciTech Connect

    Yoon, Jihyung; Jung, Jae Won, E-mail: jungj@ecu.edu; Kim, Jong Oh

    2016-05-15

    Purpose: To develop and evaluate a fast Monte Carlo (MC) dose calculation model of electronic portal imaging device (EPID) based on its effective atomic number modeling in the XVMC code. Methods: A previously developed EPID model, based on the XVMC code by density scaling of EPID structures, was modified by additionally considering effective atomic number (Z{sub eff}) of each structure and adopting a phase space file from the EGSnrc code. The model was tested under various homogeneous and heterogeneous phantoms and field sizes by comparing the calculations in the model with measurements in EPID. In order to better evaluate themore » model, the performance of the XVMC code was separately tested by comparing calculated dose to water with ion chamber (IC) array measurement in the plane of EPID. Results: In the EPID plane, calculated dose to water by the code showed agreement with IC measurements within 1.8%. The difference was averaged across the in-field regions of the acquired profiles for all field sizes and phantoms. The maximum point difference was 2.8%, affected by proximity of the maximum points to penumbra and MC noise. The EPID model showed agreement with measured EPID images within 1.3%. The maximum point difference was 1.9%. The difference dropped from the higher value of the code by employing the calibration that is dependent on field sizes and thicknesses for the conversion of calculated images to measured images. Thanks to the Z{sub eff} correction, the EPID model showed a linear trend of the calibration factors unlike those of the density-only-scaled model. The phase space file from the EGSnrc code sharpened penumbra profiles significantly, improving agreement of calculated profiles with measured profiles. Conclusions: Demonstrating high accuracy, the EPID model with the associated calibration system may be used for in vivo dosimetry of radiation therapy. Through this study, a MC model of EPID has been developed, and their performance has been

  8. A high-speed scintillation-based electronic portal imaging device to quantitatively characterize IMRT delivery.

    PubMed

    Ranade, Manisha K; Lynch, Bart D; Li, Jonathan G; Dempsey, James F

    2006-01-01

    We have developed an electronic portal imaging device (EPID) employing a fast scintillator and a high-speed camera. The device is designed to accurately and independently characterize the fluence delivered by a linear accelerator during intensity modulated radiation therapy (IMRT) with either step-and-shoot or dynamic multileaf collimator (MLC) delivery. Our aim is to accurately obtain the beam shape and fluence of all segments delivered during IMRT, in order to study the nature of discrepancies between the plan and the delivered doses. A commercial high-speed camera was combined with a terbium-doped gadolinium-oxy-sulfide (Gd2O2S:Tb) scintillator to form an EPID for the unaliased capture of two-dimensional fluence distributions of each beam in an IMRT delivery. The high speed EPID was synchronized to the accelerator pulse-forming network and gated to capture every possible pulse emitted from the accelerator, with an approximate frame rate of 360 frames-per-second (fps). A 62-segment beam from a head-and-neck IMRT treatment plan requiring 68 s to deliver was recorded with our high speed EPID producing approximately 6 Gbytes of imaging data. The EPID data were compared with the MLC instruction files and the MLC controller log files. The frames were binned to provide a frame rate of 72 fps with a signal-to-noise ratio that was sufficient to resolve leaf positions and segment fluence. The fractional fluence from the log files and EPID data agreed well. An ambiguity in the motion of the MLC during beam on was resolved. The log files reported leaf motions at the end of 33 of the 42 segments, while the EPID observed leaf motions in only 7 of the 42 segments. The static IMRT segment shapes observed by the high speed EPID were in good agreement with the shapes reported in the log files. The leaf motions observed during beam-on for step-and-shoot delivery were not temporally resolved by the log files.

  9. Clinical Trial Electronic Portals for Expedited Safety Reporting: Recommendations from the Clinical Trials Transformation Initiative Investigational New Drug Safety Advancement Project.

    PubMed

    Perez, Raymond P; Finnigan, Shanda; Patel, Krupa; Whitney, Shanell; Forrest, Annemarie

    2016-12-15

    Use of electronic clinical trial portals has increased in recent years to assist with sponsor-investigator communication, safety reporting, and clinical trial management. Electronic portals can help reduce time and costs associated with processing paperwork and add security measures; however, there is a lack of information on clinical trial investigative staff's perceived challenges and benefits of using portals. The Clinical Trials Transformation Initiative (CTTI) sought to (1) identify challenges to investigator receipt and management of investigational new drug (IND) safety reports at oncologic investigative sites and coordinating centers and (2) facilitate adoption of best practices for communicating and managing IND safety reports using electronic portals. CTTI, a public-private partnership to improve the conduct of clinical trials, distributed surveys and conducted interviews in an opinion-gathering effort to record investigator and research staff views on electronic portals in the context of the new safety reporting requirements described in the US Food and Drug Administration's final rule (Code of Federal Regulations Title 21 Section 312). The project focused on receipt, management, and review of safety reports as opposed to the reporting of adverse events. The top challenge investigators and staff identified in using individual sponsor portals was remembering several complex individual passwords to access each site. Also, certain tasks are time-consuming (eg, downloading reports) due to slow sites or difficulties associated with particular operating systems or software. To improve user experiences, respondents suggested that portals function independently of browsers and operating systems, have intuitive interfaces with easy navigation, and incorporate additional features that would allow users to filter, search, and batch safety reports. Results indicate that an ideal system for sharing expedited IND safety information is through a central portal used by

  10. Analysis of the kinestatic charge detection system as a high detective quantum efficiency electronic portal imaging device.

    PubMed

    Samant, Sanjiv S; Gopal, Arun

    2006-09-01

    Megavoltage x-ray imaging suffers from reduced image quality due to low differential x-ray attenuation and large Compton scatter compared with kilovoltage imaging. Notwithstanding this, electronic portal imaging devices (EPIDs) are now widely used in portal verification in radiotherapy as they offer significant advantages over film, including immediate digital imaging and superior contrast range. However video-camera-based EPIDs (VEPIDs) are limited by problems of low light collection efficiency and significant light scatter, leading to reduced contrast and spatial resolution. Indirect and direct detection-based flat-panel EPIDs have been developed to overcome these limitations. While flat-panel image quality has been reported to exceed that achieved with portal film, these systems have detective quantum efficiency (DQE) limited by the thin detection medium and are sensitive to radiation damage to peripheral read-out electronics. An alternative technology for high-quality portal imaging is presented here: kinesatic charge detection (KCD). The KCD is a scanning tri-electrode ion-chamber containing high-pressure noble gas (xenon at 100 atm) used in conjunction with a strip-collimated photon beam. The chamber is scanned across the patient, and an external electric field is used to regulate the cation drift velocity. By matching the scanning velocity with that of the cation (i.e., ion) drift velocity, the cations remain static in the object frame of reference, allowing temporal integration of the signal. The KCD offers several advantages as a portal imaging system. It has a thick detector geometry with an active detection depth of 6.1 cm, compared to the sub-millimeter thickness of the phosphor layer in conventional phosphor screens, leading to an order of magnitude advantage in quantum efficiency (>0.3). The unique principle of and the use of the scanning strip-collimated x-ray beam provide further integration of charges in time, reduced scatter, and a significantly

  11. Characterization of gate recessed GaN/AlGaN/GaN high electron mobility transistors fabricated using a SiCl4/SF6 dry etch recipe

    NASA Astrophysics Data System (ADS)

    Green, R. T.; Luxmoore, I. J.; Lee, K. B.; Houston, P. A.; Ranalli, F.; Wang, T.; Parbrook, P. J.; Uren, M. J.; Wallis, D. J.; Martin, T.

    2010-07-01

    Incorporating GaN capping layers in conjunction with recessing has been identified as a means to maximize the high frequency performance of AlGaN/GaN high electron mobility transistors (HEMTs). Doping the cap heavily n-type is required in order to ensure minimal loss of carriers from the channel. Using a SiCl4/SF6 dry etch plasma recipe, 250 nm gate length HEMTs with recess lengths varying from 300 nm to 5 μm are fabricated. Heavily doped n+GaN caps enabled contact resistances of 0.3 Ω mm to be achieved. Recessing using a SiCl4/SF6 recipe does not introduce significant numbers of bulk traps. Gate recessing in conjunction with Si3N4 passivation reduces rf dispersion to negligible levels.

  12. Feasibility study using a Ni-Ti stent and electronic portal imaging to localize the prostate during radiotherapy.

    PubMed

    Carl, Jesper; Lund, Bente; Larsen, Erik Hoejkjaer; Nielsen, Jane

    2006-02-01

    A new method for localization of the prostate during external beam radiotherapy is presented. The method is based on insertion of a thermo-expandable Ni-Ti stent. The stent is originally developed for treatment of bladder outlet obstruction caused by benign hyperplasia. The radiological properties of the stent are used for precise prostate localization during treatment using electronic portal images. Patients referred for intended curative radiotherapy and having a length of their prostatic urethra in the range from 25 to 65 mm were included. Pairs of isocentric orthogonal portal images were used to determine the 3D position at eight different treatment sessions for each patient. Fourteen patients were enrolled in the study. The data obtained demonstrated that the stent position was representative of the prostate location. The stent may also improve delineation of the prostate GTV, and prevent obstruction of bladder outlet during treatment. Precision in localization of the stent was less than 1 mm. Random errors in stent position were left-right 1.6 mm, cranial-caudal 2.2 mm and anterior-posterior 3.2 mm. In four of 14 patients a dislocation of the stent to the bladder occurred. Dislocation only occurred in patients with length of prostatic urethra less than 40 mm. A new method for radiological high precision localization of the prostate during radiotherapy is presented. The method is based on insertion of a standard Ni-Ti thermo-expandable stent, designed for treatment of benign prostate hyperplasia.

  13. In-situ high resolution transmission electron microscopy observation of silicon nanocrystal nucleation in a SiO{sub 2} bilayered matrix

    SciTech Connect

    Yang, T. C.-J., E-mail: terry.yang@unsw.edu.au; Wu, L.; Lin, Z.

    2014-08-04

    Solid-state nucleation of Si nanocrystals in a SiO{sub 2} bilayered matrix was observed at temperatures as low as 450 °C. This was achieved by aberration corrected high-resolution transmission electron microscopy (HRTEM) with real-time in-situ heating up to 600 °C. This technique is a valuable characterization tool especially with the recent interest in Si nanostructures for light emitting devices, non-volatile memories, and third-generation photovoltaics which all typically require a heating step in their fabrication. The control of size, shape, and distribution of the Si nanocrystals are critical for these applications. This experimental study involves in-situ observation of the nucleation of Si nanocrystals inmore » a SiO{sub 2} bilayered matrix fabricated through radio frequency co-sputtering. The results show that the shapes of Si nanocrystals in amorphous SiO{sub 2} bilayered matrices are irregular and not spherical, in contrast to many claims in the literature. Furthermore, the Si nanocrystals are well confined within their layers by the amorphous SiO{sub 2}. This study demonstrates the potential of in-situ HRTEM as a tool to observe the real time nucleation of Si nanocrystals in a SiO{sub 2} bilayered matrix. Furthermore, ideas for improvements on this in-situ heating HRTEM technique are discussed.« less

  14. Flat-panel detector, CCD cameras, and electron-beam-tube-based video for use in portal imaging

    NASA Astrophysics Data System (ADS)

    Roehrig, Hans; Tang, Chuankun; Cheng, Chee-Way; Dallas, William J.

    1998-07-01

    This paper provides a comparison of some imaging parameters of four portal imaging systems at 6 MV: a flat panel detector, two CCD cameras and an electron beam tube based video camera. Measurements were made of signal and noise and consequently of signal-to-noise per pixel as a function of the exposure. All systems have a linear response with respect to exposure, and with the exception of the electron beam tube based video camera, the noise is proportional to the square-root of the exposure, indicating photon-noise limitation. The flat-panel detector has a signal-to-noise ratio, which is higher than that observed with both CCD-Cameras or with the electron beam tube based video camera. This is expected because most portal imaging systems using optical coupling with a lens exhibit severe quantum-sinks. The measurements of signal-and noise were complemented by images of a Las Vegas-type aluminum contrast detail phantom, located at the ISO-Center. These images were generated at an exposure of 1 MU. The flat-panel detector permits detection of Aluminum holes of 1.2 mm diameter and 1.6 mm depth, indicating the best signal-to-noise ratio. The CCD-cameras rank second and third in signal-to- noise ratio, permitting detection of Aluminum-holes of 1.2 mm diameter and 2.2 mm depth (CCD_1) and of 1.2 mm diameter and 3.2 mm depth (CCD_2) respectively, while the electron beam tube based video camera permits detection of only a hole of 1.2 mm diameter and 4.6 mm depth. Rank Order Filtering was applied to the raw images from the CCD-based systems in order to remove the direct hits. These are camera responses to scattered x-ray photons which interact directly with the CCD of the CCD-Camera and generate 'Salt and Pepper type noise,' which interferes severely with attempts to determine accurate estimates of the image noise. The paper also presents data on the metal-phosphor's photon gain (the number of light-photons per interacting x-ray photon).

  15. Patterns of Electronic Portal Use among Vulnerable Patients in a Nationwide Practice-based Research Network: From the OCHIN Practice-based Research Network (PBRN)

    PubMed Central

    Wallace, Lorraine S.; Angier, Heather; Huguet, Nathalie; Gaudino, James A.; Krist, Alex; Dearing, Marla; Killerby, Marie; Marino, Miguel; DeVoe, Jennifer E.

    2017-01-01

    Background Underserved patient populations experience barriers to accessing and engaging within the complex health care system. Electronic patient portals have been proposed as a potential new way to improve access and engagement. We studied patient portal use for 12 consecutive months (365 days) among a large, nationally distributed, underserved patient population within the OCHIN (originally created as the Oregon Community Health Information Network and renamed OCHIN as other states joined) practice-based research network (PBRN). Methods We retrospectively assessed adoption and use of Epic’s MyChart patient portal in the first 12 months after MyChart was made available to the OCHIN PBRN. We examined electronic health record data from 36,549 patients aged ≥18 years who were offered a MyChart access code between May 1, 2012, and April 30, 2013, across the OCHIN PBRN in 13 states. Results Overall, 29% of patients offered an access code logged into their MyChart account. Superusers (minimum of 2 logins per month over a 12-month period) accounted for 6% of users overall. Men, nonwhite patients, Hispanic patients, Spanish-speaking patients, and those with the lowest incomes were significantly less likely to activate. Publicly insured and uninsured patients were also less likely to log in to their MyChart account, but once activated they were more likely than privately insured patients to use MyChart functions. Conclusions Our findings suggest that, compared with others, certain patient groups may be less interested in using patient portals or may have experienced significant barriers that prevented use. Making portal access available is a first step. Additional studies need to specifically identify health system–, clinic-, and patient-level barriers and facilitators to portal adoption and use. PMID:27613792

  16. Optimization of image quality and dose for Varian aS500 electronic portal imaging devices (EPIDs).

    PubMed

    McGarry, C K; Grattan, M W D; Cosgrove, V P

    2007-12-07

    This study was carried out to investigate whether the electronic portal imaging (EPI) acquisition process could be optimized, and as a result tolerance and action levels be set for the PIPSPro QC-3V phantom image quality assessment. The aim of the optimization process was to reduce the dose delivered to the patient while maintaining a clinically acceptable image quality. This is of interest when images are acquired in addition to the planned patient treatment, rather than images being acquired using the treatment field during a patient's treatment. A series of phantoms were used to assess image quality for different acquisition settings relative to the baseline values obtained following acceptance testing. Eight Varian aS500 EPID systems on four matched Varian 600C/D linacs and four matched Varian 2100C/D linacs were compared for consistency of performance and images were acquired at the four main orthogonal gantry angles. Images were acquired using a 6 MV beam operating at 100 MU min(-1) and the low-dose acquisition mode. Doses used in the comparison were measured using a Farmer ionization chamber placed at d(max) in solid water. The results demonstrated that the number of reset frames did not have any influence on the image contrast, but the number of frame averages did. The expected increase in noise with corresponding decrease in contrast was also observed when reducing the number of frame averages. The optimal settings for the low-dose acquisition mode with respect to image quality and dose were found to be one reset frame and three frame averages. All patients at the Northern Ireland Cancer Centre are now imaged using one reset frame and three frame averages in the 6 MV 100 MU min(-1) low-dose acquisition mode. Routine EPID QC contrast tolerance (+/-10) and action (+/-20) levels using the PIPSPro phantom based around expected values of 190 (Varian 600C/D) and 225 (Varian 2100C/D) have been introduced. The dose at dmax from electronic portal imaging has been

  17. Electronic Portfolios as Living Portals: A Narrative Inquiry into College Student Learning, Identity, and Assessment

    ERIC Educational Resources Information Center

    Nguyen, Celeste Fowles

    2013-01-01

    As universities increasingly utilize electronic portfolios, college students are asked more than ever to create ePortfolios for academics, assessment, or advising. This study shifts an analysis of ePortfolios from prior epistemological approaches, where ePortfolios have been explored as a tool to measure student progress, onto an ontological…

  18. SU-G-BRA-06: Quantification of Tracking Performance of a Multi-Layer Electronic Portal Imaging Device

    SciTech Connect

    Hu, Y; Rottmann, J; Myronakis, M

    2016-06-15

    Purpose: The purpose of this study was to quantify the improvement in tumor tracking, with and without fiducial markers, afforded by employing a multi-layer (MLI) electronic portal imaging device (EPID) over the current state-of-the-art, single-layer, digital megavolt imager (DMI) architecture. Methods: An ideal observer signal-to-noise ratio (d’) approach was used to quantify the ability of an MLI EPID and a current, state-of-the-art DMI EPID to track lung tumors from the treatment beam’s-eye-view. Using each detector modulation transfer function (MTF) and noise power spectrum (NPS) as inputs, a detection task was employed with object functions describing simple three-dimensional Cartesian shapes (spheresmore » and cylinders). Marker-less tumor tracking algorithms often use texture discrimination to differentiate benign and malignant tissue. The performance of such algorithms is simulated by employing a discrimination task for the ideal observer, which measures the ability of a system to differentiate two image quantities. These were defined as the measured textures for benign and malignant lung tissue. Results: The NNPS of the MLI ∼25% of that of the DMI at the expense of decreased MTF at intermediate frequencies (0.25≤« less

  19. Patient Portals

    PubMed Central

    Skinner, Asheley; Thornhill, Jonathan; Weinberger, Morris

    2016-01-01

    Summary Background Patient portals have demonstrated numerous benefits including improved patient-provider communication, patient satisfaction with care, and patient engagement. Recent literature has begun to illustrate how patients use selected portal features and an association between portal usage and improved clinical outcomes. Objectives This study sought to: (1) identify patient characteristics associated with the use of a patient portal; (2) determine the frequency with which common patient portal features are used; and (3) examine whether the level of patient portal use (non-users, light users, active users) is associated with 30-day hospital readmission. Methods My UNC Chart is the patient portal for the UNC Health Care System. We identified adults discharged from three UNC Health Care hospitals with acute myocardial infarction, congestive heart failure, or pneumonia and classified them as active, light, or non-users of My UNC Chart. Multivariable analyses were conducted to compare across user groups; logistic regression was used to predict whether patient portal use was associated with 30-day readmission. Results Of 2,975 eligible patients, 83.4% were non-users; 8.6% were light users; and 8.0% were active users of My UNC Chart. The messaging feature was used most often. For patients who were active users, the odds of being readmitted within 30 days was 66% greater than patients who were non-users (p<0.05). There was no difference in 30-day readmission between non-users and light users. Conclusions The vast majority of patients who were given an access code for My UNC Chart did not use it within 30 days of discharge. Of those who used the portal, active users had a higher odds of being readmitted within 30 days. Health care systems should consider strategies to: (1) increase overall use of patient portals and (2) target patients with the highest comorbidity scores to reduce hospital readmissions. PMID:27437056

  20. Measured and Simulated Dark J-V Characteristics of a-Si:H Single Junction p-i-n Solar Cells Irradiated with 40 keV Electrons

    NASA Technical Reports Server (NTRS)

    Lord, Kenneth; Woodyard, James R.

    2002-01-01

    The effect of 40 keV electron irradiation on a-Si:H p-i-n single-junction solar cells was investigated using measured and simulated dark J-V characteristics. EPRI-AMPS and PC-1D simulators were explored for use in the studies. The EPRI-AMPS simulator was employed and simulator parameters selected to produce agreement with measured J-V characteristics. Three current mechanisms were evident in the measured dark J-V characteristics after electron irradiation, namely, injection, shunting and a term of the form CV(sup m). Using a single discrete defect state level at the center of the band gap, good agreement was achieved between measured and simulated J-V characteristics in the forward-bias voltage region where the dark current density was dominated by injection. The current mechanism of the form CV(sup m) was removed by annealing for two hours at 140 C. Subsequent irradiation restored the CV(sup m) current mechanism and it was removed by a second anneal. Some evidence of the CV(sup m) term is present in device simulations with a higher level of discrete density of states located at the center of the bandgap.

  1. A dual two dimensional electronic portal imaging device transit dosimetry model based on an empirical quadratic formalism

    PubMed Central

    Metwaly, M; Glegg, M; Baggarley, S P; Elliott, A

    2015-01-01

    Objective: This study describes a two dimensional electronic portal imaging device (EPID) transit dosimetry model that can predict either: (1) in-phantom exit dose, or (2) EPID transit dose, for treatment verification. Methods: The model was based on a quadratic equation that relates the reduction in intensity to the equivalent path length (EPL) of the attenuator. In this study, two sets of quadratic equation coefficients were derived from calibration dose planes measured with EPID and ionization chamber in water under reference conditions. With two sets of coefficients, EPL can be calculated from either EPID or treatment planning system (TPS) dose planes. Consequently, either the in-phantom exit dose or the EPID transit dose can be predicted from the EPL. The model was tested with two open, five wedge and seven sliding window prostate and head and neck intensity-modulated radiation therapy (IMRT) fields on phantoms. Results were analysed using absolute gamma analysis (3%/3 mm). Results: The open fields gamma pass rates were >96.8% for all comparisons. For wedge and IMRT fields, comparisons between predicted and TPS-computed in-phantom exit dose resulted in mean gamma pass rate of 97.4% (range, 92.3–100%). As for the comparisons between predicted and measured EPID transit dose, the mean gamma pass rate was 97.5% (range, 92.6–100%). Conclusion: An EPID transit dosimetry model that can predict in-phantom exit dose and EPID transit dose was described and proven to be valid. Advances in knowledge: The described model is practical, generic and flexible to encourage widespread implementation of EPID dosimetry for the improvement of patients' safety in radiotherapy. PMID:25969867

  2. Cost minimisation analysis: kilovoltage imaging with automated repositioning versus electronic portal imaging in image-guided radiotherapy for prostate cancer.

    PubMed

    Gill, S; Younie, S; Rolfo, A; Thomas, J; Siva, S; Fox, C; Kron, T; Phillips, D; Tai, K H; Foroudi, F

    2012-10-01

    To compare the treatment time and cost of prostate cancer fiducial marker image-guided radiotherapy (IGRT) using orthogonal kilovoltage imaging (KVI) and automated couch shifts and orthogonal electronic portal imaging (EPI) and manual couch shifts. IGRT treatment delivery times were recorded automatically on either unit. Costing was calculated from real costs derived from the implementation of a new radiotherapy centre. To derive cost per minute for EPI and KVI units the total annual setting up and running costs were divided by the total annual working time. The cost per IGRT fraction was calculated by multiplying the cost per minute by the duration of treatment. A sensitivity analysis was conducted to test the robustness of our analysis. Treatment times without couch shift were compared. Time data were analysed for 8648 fractions, 6057 from KVI treatment and 2591 from EPI treatment from a total of 294 patients. The median time for KVI treatment was 6.0 min (interquartile range 5.1-7.4 min) and for EPI treatment it was 10.0 min (interquartile range 8.3-11.8 min) (P value < 0.0001). The cost per fraction for KVI was A$258.79 and for EPI was A$345.50. The cost saving per fraction for KVI varied between A$66.09 and A$101.64 by sensitivity analysis. In patients where no couch shift was made, the median treatment delivery time for EPI was 8.8 min and for KVI was 5.1 min. Treatment time is less on KVI units compared with EPI units. This is probably due to automation of couch shift and faster evaluation of imaging on KVI units. Annual running costs greatly outweigh initial setting up costs and therefore the cost per fraction was less with KVI, despite higher initial costs. The selection of appropriate IGRT equipment can make IGRT practical within radiotherapy departments. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  3. A new approach for the pixel map sensitivity (PMS) evaluation of an electronic portal imaging device (EPID)

    PubMed Central

    Lucio, Francesco; Calamia, Elisa; Russi, Elvio; Marchetto, Flavio

    2013-01-01

    When using an electronic portal imaging device (EPID) for dosimetric verifications, the calibration of the sensitive area is of paramount importance. Two calibration methods are generally adopted: one, empirical, based on an external reference dosimeter or on multiple narrow beam irradiations, and one based on the EPID response simulation. In this paper we present an alternative approach based on an intercalibration procedure, independent from external dosimeters and from simulations, and is quick and easy to perform. Each element of a detector matrix is characterized by a different gain; the aim of the calibration procedure is to relate the gain of each element to a reference one. The method that we used to compute the relative gains is based on recursive acquisitions with the EPID placed in different positions, assuming a constant fluence of the beam for subsequent deliveries. By applying an established procedure and analysis algorithm, the EPID calibration was repeated in several working conditions. Data show that both the photons energy and the presence of a medium between the source and the detector affect the calibration coefficients less than 1%. The calibration coefficients were then applied to the acquired images, comparing the EPID dose images with films. Measurements were performed with open field, placing the film at the level of the EPID. The standard deviation of the distribution of the point‐to‐point difference is 0.6%. An approach of this type for the EPID calibration has many advantages with respect to the standard methods — it does not need an external dosimeter, it is not related to the irradiation techniques, and it is easy to implement in the clinical practice. Moreover, it can be applied in case of transit or nontransit dosimetry, solving the problem of the EPID calibration independently from the dose reconstruction method. PACS number: 87.56.‐v PMID:24257285

  4. Fast 3D dosimetric verifications based on an electronic portal imaging device using a GPU calculation engine.

    PubMed

    Zhu, Jinhan; Chen, Lixin; Chen, Along; Luo, Guangwen; Deng, Xiaowu; Liu, Xiaowei

    2015-04-11

    To use a graphic processing unit (GPU) calculation engine to implement a fast 3D pre-treatment dosimetric verification procedure based on an electronic portal imaging device (EPID). The GPU algorithm includes the deconvolution and convolution method for the fluence-map calculations, the collapsed-cone convolution/superposition (CCCS) algorithm for the 3D dose calculations and the 3D gamma evaluation calculations. The results of the GPU-based CCCS algorithm were compared to those of Monte Carlo simulations. The planned and EPID-based reconstructed dose distributions in overridden-to-water phantoms and the original patients were compared for 6 MV and 10 MV photon beams in intensity-modulated radiation therapy (IMRT) treatment plans based on dose differences and gamma analysis. The total single-field dose computation time was less than 8 s, and the gamma evaluation for a 0.1-cm grid resolution was completed in approximately 1 s. The results of the GPU-based CCCS algorithm exhibited good agreement with those of the Monte Carlo simulations. The gamma analysis indicated good agreement between the planned and reconstructed dose distributions for the treatment plans. For the target volume, the differences in the mean dose were less than 1.8%, and the differences in the maximum dose were less than 2.5%. For the critical organs, minor differences were observed between the reconstructed and planned doses. The GPU calculation engine was used to boost the speed of 3D dose and gamma evaluation calculations, thus offering the possibility of true real-time 3D dosimetric verification.

  5. Design and implementation of a web-based patient portal linked to an ambulatory care electronic health record: patient gateway for diabetes collaborative care.

    PubMed

    Grant, Richard W; Wald, Jonathan S; Poon, Eric G; Schnipper, Jeffrey L; Gandhi, Tejal K; Volk, Lynn A; Middleton, Blackford

    2006-10-01

    Despite the availability of expert guidelines and widespread diabetes quality improvement efforts, care of patients with diabetes remains suboptimal. Two key barriers to care that may be amenable to informatics-based interventions include (1) lack of patient engagement with therapeutic care plans and (2) lack of medication adjustment by physicians ("clinical inertia") during clinical encounters. The authors describe the conceptual framework, design, implementation, and analysis plan for a diabetes patient web-portal linked directly to the electronic health record (EHR) of a large academic medical center via secure Internet access designed to overcome barriers to effective diabetes care. Partners HealthCare System (Boston, MA), a multi-hospital health care network comprising several thousand physicians caring for over 1 million individual patients, has developed a comprehensive patient web-portal called Patient Gateway that allows patients to interact directly with their EHR via secure Internet access. Using this portal, a specific diabetes interface was designed to maximize patient engagement by importing the patient's current clinical data in an educational format, providing patient-tailored decision support, and enabling the patient to author a "Diabetes Care Plan." The physician view of the patient's Diabetes Care Plan was designed to be concise and to fit into typical EHR clinical workflow. We successfully designed and implemented a Diabetes Patient portal that allows direct interaction with our system's EHR. We are assessing the impact of this advanced informatics tool for collaborative diabetes care in a clinic-randomized controlled trial among 14 primary care practices within our integrated health care system.

  6. Health literacy and patient portals.

    PubMed

    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. Monte Carlo simulation of a novel water-equivalent electronic portal imaging device using plastic scintillating fibers.

    PubMed

    Teymurazyan, A; Pang, G

    2012-03-01

    Most electronic portal imaging devices (EPIDs) developed so far use a thin Cu plate/phosphor screen to convert x-ray energies into light photons, while maintaining a high spatial resolution. This results in a low x-ray absorption and thus a low quantum efficiency (QE) of approximately 2-4% for megavoltage (MV) x-rays. A significant increase of QE is desirable for applications such as MV cone-beam computed tomography (MV-CBCT). Furthermore, the Cu plate/phosphor screen contains high atomic number (high-Z) materials, resulting in an undesirable over-response to low energy x-rays (due to photoelectric effect) as well as high energy x-rays (due to pair production) when used for dosimetric verification. Our goal is to develop a new MV x-ray detector that has a high QE and uses low-Z materials to overcome the obstacles faced by current MV x-ray imaging technologies. A new high QE and low-Z EPID is proposed. It consists of a matrix of plastic scintillating fibers embedded in a water-equivalent medium and coupled to an optically sensitive 2D active matrix flat panel imager (AMFPI) for image readout. It differs from the previous approach that uses segmented crystalline scintillators made of higher density and higher atomic number materials to detect MV x-rays. The plastic scintillating fibers are focused toward the x-ray source to avoid image blurring due to oblique incidence of off-axis x-rays. When MV x-rays interact with the scintillating fibers in the detector, scintillation light will be produced. The light photons produced in a fiber core and emitted within the acceptance angle of the fiber will be guided toward the AMFPI by total internal reflection. A Monte Carlo simulation has been used to investigate imaging and dosimetric characteristics of the proposed detector under irradiation of MV x-rays. Properties, such as detection efficiency, modulation transfer function, detective quantum efficiency (DQE), energy dependence of detector response, and water-equivalence of

  8. Setup in a clinical workflow and impact on radiotherapy routine of an in vivo dosimetry procedure with an electronic portal imaging device

    PubMed Central

    Piermattei, Angelo; Kang, Shengwei; Xiao, Mingyong; Tang, Bin; Liao, Xiongfei; Xin, Xin; Grusio, Mattia

    2018-01-01

    High conformal techniques such as intensity-modulated radiation therapy and volumetric-modulated arc therapy are widely used in overloaded radiotherapy departments. In vivo dosimetric screening is essential in this environment to avoid important dosimetric errors. This work examines the feasibility of introducing in vivo dosimetry (IVD) checks in a radiotherapy routine. The causes of dosimetric disagreements between delivered and planned treatments were identified and corrected during the course of treatment. The efficiency of the corrections performed and the added workload needed for the entire procedure were evaluated. The IVD procedure was based on an electronic portal imaging device. A total of 3682 IVD tests were performed for 147 patients who underwent head and neck, abdomen, pelvis, breast, and thorax radiotherapy treatments. Two types of indices were evaluated and used to determine if the IVD tests were within tolerance levels: the ratio R between the reconstructed and planned isocentre doses and a transit dosimetry based on the γ-analysis of the electronic portal images. The causes of test outside tolerance level were investigated and corrected and IVD test was repeated during subsequent fraction. The time needed for each step of the IVD procedure was registered. Pelvis, abdomen, and head and neck treatments had 10% of tests out of tolerance whereas breast and thorax treatments accounted for up to 25%. The patient setup was the main cause of 90% of the IVD tests out of tolerance and the remaining 10% was due to patient morphological changes. An average time of 42 min per day was sufficient to monitor a daily workload of 60 patients in treatment. This work shows that IVD performed with an electronic portal imaging device is feasible in an overloaded department and enables the timely realignment of the treatment quality indices in order to achieve a patient’s final treatment compliant with the one prescribed. PMID:29432473

  9. Comprehensive photonics-electronics convergent simulation and its application to high-speed electronic circuit integration on a Si/Ge photonic chip

    NASA Astrophysics Data System (ADS)

    Takeda, Kotaro; Honda, Kentaro; Takeya, Tsutomu; Okazaki, Kota; Hiraki, Tatsurou; Tsuchizawa, Tai; Nishi, Hidetaka; Kou, Rai; Fukuda, Hiroshi; Usui, Mitsuo; Nosaka, Hideyuki; Yamamoto, Tsuyoshi; Yamada, Koji

    2015-01-01

    We developed a design technique for a photonics-electronics convergence system by using an equivalent circuit of optical devices in an electrical circuit simulator. We used the transfer matrix method to calculate the response of an optical device. This method used physical parameters and dimensions of optical devices as calculation parameters to design a device in the electrical circuit simulator. It also used an intermediate frequency to express the wavelength dependence of optical devices. By using both techniques, we simulated bit error rates and eye diagrams of optical and electrical integrated circuits and calculated influences of device structure change and wavelength shift penalty.

  10. International Portal

    EIA Publications

    The International Energy Portal includes a powerful data browser that provides country-level energy data; many countries have at least 30 years of historical data. The data browser provides users the ability to view and download complete datasets for consumption, production, trade, reserves, and carbon dioxide emissions for different fuels and energy sources.

  11. Four-dimensional dose reconstruction through in vivo phase matching of cine images of electronic portal imaging device

    SciTech Connect

    Yoon, Jihyung; Jung, Jae Won, E-mail: jungj@ecu.ed

    Purpose: A method is proposed to reconstruct a four-dimensional (4D) dose distribution using phase matching of measured cine images to precalculated images of electronic portal imaging device (EPID). Methods: (1) A phantom, designed to simulate a tumor in lung (a polystyrene block with a 3 cm diameter embedded in cork), was placed on a sinusoidally moving platform with an amplitude of 1 cm and a period of 4 s. Ten-phase 4D computed tomography (CT) images of the phantom were acquired. A planning target volume (PTV) was created by adding a margin of 1 cm around the internal target volume ofmore » the tumor. (2) Three beams were designed, which included a static beam, a theoretical dynamic beam, and a planning-optimized dynamic beam (PODB). While the theoretical beam was made by manually programming a simplistic sliding leaf motion, the planning-optimized beam was obtained from treatment planning. From the three beams, three-dimensional (3D) doses on the phantom were calculated; 4D dose was calculated by means of the ten phase images (integrated over phases afterward); serving as “reference” images, phase-specific EPID dose images under the lung phantom were also calculated for each of the ten phases. (3) Cine EPID images were acquired while the beams were irradiated to the moving phantom. (4) Each cine image was phase-matched to a phase-specific CT image at which common irradiation occurred by intercomparing the cine image with the reference images. (5) Each cine image was used to reconstruct dose in the phase-matched CT image, and the reconstructed doses were summed over all phases. (6) The summation was compared with forwardly calculated 4D and 3D dose distributions. Accounting for realistic situations, intratreatment breathing irregularity was simulated by assuming an amplitude of 0.5 cm for the phantom during a portion of breathing trace in which the phase matching could not be performed. Intertreatment breathing irregularity between the time of treatment

  12. Four-dimensional dose reconstruction through in vivo phase matching of cine images of electronic portal imaging device.

    PubMed

    Yoon, Jihyung; Jung, Jae Won; Kim, Jong Oh; Yi, Byong Yong; Yeo, Inhwan

    2016-07-01

    A method is proposed to reconstruct a four-dimensional (4D) dose distribution using phase matching of measured cine images to precalculated images of electronic portal imaging device (EPID). (1) A phantom, designed to simulate a tumor in lung (a polystyrene block with a 3 cm diameter embedded in cork), was placed on a sinusoidally moving platform with an amplitude of 1 cm and a period of 4 s. Ten-phase 4D computed tomography (CT) images of the phantom were acquired. A planning target volume (PTV) was created by adding a margin of 1 cm around the internal target volume of the tumor. (2) Three beams were designed, which included a static beam, a theoretical dynamic beam, and a planning-optimized dynamic beam (PODB). While the theoretical beam was made by manually programming a simplistic sliding leaf motion, the planning-optimized beam was obtained from treatment planning. From the three beams, three-dimensional (3D) doses on the phantom were calculated; 4D dose was calculated by means of the ten phase images (integrated over phases afterward); serving as "reference" images, phase-specific EPID dose images under the lung phantom were also calculated for each of the ten phases. (3) Cine EPID images were acquired while the beams were irradiated to the moving phantom. (4) Each cine image was phase-matched to a phase-specific CT image at which common irradiation occurred by intercomparing the cine image with the reference images. (5) Each cine image was used to reconstruct dose in the phase-matched CT image, and the reconstructed doses were summed over all phases. (6) The summation was compared with forwardly calculated 4D and 3D dose distributions. Accounting for realistic situations, intratreatment breathing irregularity was simulated by assuming an amplitude of 0.5 cm for the phantom during a portion of breathing trace in which the phase matching could not be performed. Intertreatment breathing irregularity between the time of treatment and the time of planning CT was

  13. Patient portal doldrums: does an exam room promotional video during an office visit increase patient portal registrations and portal use?

    PubMed

    North, Frederick; Hanna, Barbara K; Crane, Sarah J; Smith, Steven A; Tulledge-Scheitel, Sidna M; Stroebel, Robert J

    2011-12-01

    The patient portal is a web service which allows patients to view their electronic health record, communicate online with their care teams, and manage healthcare appointments and medications. Despite advantages of the patient portal, registrations for portal use have often been slow. Using a secure video system on our existing exam room electronic health record displays during regular office visits, the authors showed patients a video which promoted use of the patient portal. The authors compared portal registrations and portal use following the video to providing a paper instruction sheet and to a control (no additional portal promotion). From the 12,050 office appointments examined, portal registrations within 45 days of the appointment were 11.7%, 7.1%, and 2.5% for video, paper instructions, and control respectively (p<0.0001). Within 6 months following the interventions, 3.5% in the video cohort, 1.2% in the paper, and 0.75% of the control patients demonstrated portal use by initiating portal messages to their providers (p<0.0001).

  14. A simple quality assurance test tool for the visual verification of light and radiation field congruent using electronic portal images device and computed radiography

    PubMed Central

    2012-01-01

    Background The radiation field on most megavoltage radiation therapy units are shown by a light field projected through the collimator by a light source mounted inside the collimator. The light field is traditionally used for patient alignment. Hence it is imperative that the light field is congruent with the radiation field. Method A simple quality assurance tool has been designed for rapid and simple test of the light field and radiation field using electronic portal images device (EPID) or computed radiography (CR). We tested this QA tool using Varian PortalVision and Elekta iViewGT EPID systems and Kodak CR system. Results Both the single and double exposure techniques were evaluated, with double exposure technique providing a better visualization of the light-radiation field markers. The light and radiation congruency could be detected within 1 mm. This will satisfy the American Association of Physicists in Medicine task group report number 142 recommendation of 2 mm tolerance. Conclusion The QA tool can be used with either an EPID or CR to provide a simple and rapid method to verify light and radiation field congruence. PMID:22452821

  15. The provider perspective: investigating the effect of the Electronic Patient-Reported Outcome (ePRO) mobile application and portal on primary care provider workflow.

    PubMed

    Hans, Parminder K; Gray, Carolyn Steele; Gill, Ashlinder; Tiessen, James

    2018-03-01

    Aim This qualitative study investigates how the Electronic Patient-Reported Outcome (ePRO) mobile application and portal system, designed to capture patient-reported measures to support self-management, affected primary care provider workflows. The Canadian health system is facing an ageing population that is living with chronic disease. Disruptive innovations like mobile health technologies can help to support health system transformation needed to better meet the multifaceted needs of the complex care patient. However, there are challenges with implementing these technologies in primary care settings, in particular the effect on primary care provider workflows. Over a six-week period interdisciplinary primary care providers (n=6) and their complex care patients (n=12), used the ePRO mobile application and portal to collaboratively goal-set, manage care plans, and support self-management using patient-reported measures. Secondary thematic analysis of focus groups, training sessions, and issue tracker reports captured user experiences at a Toronto area Family Health Team from October 2014 to January 2015. Findings Key issues raised by providers included: liability concerns associated with remote monitoring, increased documentation activities due to a lack of interoperability between the app and the electronic patient record, increased provider anxiety with regard to the potential for the app to disrupt and infringe upon appointment time, and increased demands for patient engagement. Primary care providers reported the app helped to focus care plans and to begin a collaborative conversation on goal-setting. However, throughout our investigation we found a high level of provider resistance evidenced by consistent attempts to shift the app towards fitting with existing workflows rather than adapting much of their behaviour. As health systems seek innovative and disruptive models to better serve this complex patient population, provider change resistance will need to

  16. A double exposed portal image comparison between electronic portal imaging hard copies and port films in radiation therapy treatment setup confirmation to determine its clinical application in a radiotherapy center.

    PubMed

    Hatherly, K E; Smylie, J C; Rodger, A; Dally, M J; Davis, S R; Millar, J L

    2001-01-01

    At the William Buckland Radiotherapy Center (WBRC), field-only electronic portal image (EPI) hard copies are used for radiation treatment field verification for whole brain, breast, chest, spine, and large pelvic fields, as determined by a previous study. A subsequent research project, addressing the quality of double exposed EPI hard copies for sites where field only EPI was not considered adequate to determine field placement, has been undertaken. The double exposed EPI hard copies were compared to conventional double exposed port films for small pelvic, partial brain, and head and neck fields and for a miscellaneous group. All double exposed EPIs were captured during routine clinical procedures using liquid ion chamber cassettes. EPI hard copies were generated using a Visiplex multi-format camera. In sites where port film remained the preferred verification format, the port films were generated as per department protocol. In addition EPIs were collected specifically for this project. Four radiation oncologists performed the evaluation of EPI and port film images independently with a questionnaire completed at each stage of the evaluation process to assess the following: Adequacy of information in the image to assess field placement. Adequacy of information for determining field placement correction. Clinician's preferred choice of imaging for field placement assessment The results indicate that double exposed EPI hard copies generally do containsufficient information to permit evaluation of field placement and can replace conventionaldouble exposed port films in a significant number of sites. These include the following:pelvis fields < 12 X 12 cm, partial brain fields, and a miscellaneous group. However forradical head and neck fields, the preferred verification image format remained port film dueto the image hard copy size and improved contrast for this media. Thus in this departmenthard copy EPI is the preferred modality of field verification for all sites

  17. A study on dosimetric properties of electronic portal imaging device and its use as a quality assurance tool in Volumetric Modulated Arc Therapy

    PubMed Central

    Sukumar, Prabakar; Padmanaban, Sriram; Jeevanandam, Prakash; Syam Kumar, S.A.; Nagarajan, Vivekanandan

    2011-01-01

    Aim In this study, the dosimetric properties of the electronic portal imaging device were examined and the quality assurance testing of Volumetric Modulated Arc Therapy was performed. Background RapidArc involves the variable dose rate, leaf speed and the gantry rotation. The imager was studied for the effects like dose, dose rate, field size, leaf speed and sag during gantry rotation. Materials and methods A Varian RapidArc machine equipped with 120 multileaf collimator and amorphous silicon detector was used for the study. The characteristics that are variable in RapidArc treatment were studied for the portal imager. The accuracy of a dynamic multileaf collimator position at different gantry angles and during gantry rotation was examined using the picket fence test. The control of the dose rate and gantry speed was verified using a test field irradiating seven strips of the same dose with different dose rate and gantry speeds. The control over leaf speed during arc was verified by irradiating four strips of different leaf speeds with the same dose in each strip. To verify the results, the RapidArc test procedure was compared with the X-Omat film and verified for a period of 6 weeks using EPID. Results The effect of gantry rotation on leaf accuracy was minimal. The dose in segments showed good agreement with mean deviation of 0.8% for dose rate control and 1.09% for leaf speed control over different gantry speeds. Conclusion The results provided a precise control of gantry speed, dose rate and leaf speeds during RapidArc delivery and were consistent over 6 weeks. PMID:24376989

  18. Optimisation of the imaging and dosimetric characteristics of an electronic portal imaging device employing plastic scintillating fibres using Monte Carlo simulations.

    PubMed

    Blake, S J; McNamara, A L; Vial, P; Holloway, L; Kuncic, Z

    2014-11-21

    A Monte Carlo model of a novel electronic portal imaging device (EPID) has been developed using Geant4 and its performance for imaging and dosimetry applications in radiotherapy has been characterised. The EPID geometry is based on a physical prototype under ongoing investigation and comprises an array of plastic scintillating fibres in place of the metal plate/phosphor screen in standard EPIDs. Geometrical and optical transport parameters were varied to investigate their impact on imaging and dosimetry performance. Detection efficiency was most sensitive to variations in fibre length, achieving a peak value of 36% at 50 mm using 400 keV x-rays for the lengths considered. Increases in efficiency for longer fibres were partially offset by reductions in sensitivity. Removing the extra-mural absorber surrounding individual fibres severely decreased the modulation transfer function (MTF), highlighting its importance in maximising spatial resolution. Field size response and relative dose profile simulations demonstrated a water-equivalent dose response and thus the prototype's suitability for dosimetry applications. Element-to-element mismatch between scintillating fibres and underlying photodiode pixels resulted in a reduced MTF for high spatial frequencies and quasi-periodic variations in dose profile response. This effect is eliminated when fibres are precisely matched to underlying pixels. Simulations strongly suggest that with further optimisation, this prototype EPID may be capable of simultaneous imaging and dosimetry in radiotherapy.

  19. Portal radiation monitor

    DOEpatents

    Kruse, Lyle W.

    1985-01-01

    A portal radiation monitor combines 0.1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  20. Portal radiation monitor

    DOEpatents

    Kruse, L.W.

    1982-03-23

    A portal radiation monitor combines .1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  1. Evaluating Open Source Portals

    ERIC Educational Resources Information Center

    Goh, Dion; Luyt, Brendan; Chua, Alton; Yee, See-Yong; Poh, Kia-Ngoh; Ng, How-Yeu

    2008-01-01

    Portals have become indispensable for organizations of all types trying to establish themselves on the Web. Unfortunately, there have only been a few evaluative studies of portal software and even fewer of open source portal software. This study aims to add to the available literature in this important area by proposing and testing a checklist for…

  2. Noncirrhotic Portal Hypertension

    PubMed Central

    Rajekar, Harshal; Vasishta, Rakesh K; Chawla, Yogesh K; Dhiman, Radha K

    2011-01-01

    Portal hypertension is characterized by an increase in portal pressure (> 10 mmHg) and could be a result of cirrhosis of the liver or of noncirrhotic diseases. When portal hypertension occurs in the absence of liver cirrhosis, noncirrhotic portal hypertension (NCPH) must be considered. The prognosis of this disease is much better than that of cirrhosis. Noncirrhotic diseases are the common cause of portal hypertension in developing countries, especially in Asia. NCPH is a heterogeneous group of diseases that is due to intrahepatic or extrahepatic etiologies. In general, the lesions in NCPH are vascular in nature and can be classified based on the site of resistance to blood flow. In most cases, these disorders can be explained by endothelial cell lesions, intimal thickening, thrombotic obliterations, or scarring of the intrahepatic portal or hepatic venous circulation. Many different conditions can determine NCPH through the association of these various lesions in various degrees. Many clinical manifestations of NCPH result from the secondary effects of portal hypertension. Patients with NCPH present with upper gastrointestinal bleeding, splenomegaly, ascites after gastrointestinal bleeding, features of hypersplenism, growth retardation, and jaundice due to portal hypertensive biliopathy. Other sequelae include hyperdynamic circulation, pulmonary complications, and other effects of portosystemic collateral circulation like portosystemic encephalopathy. At present, pharmacologic and endoscopic treatments are the treatments of choice for portal hypertension. The therapy of all disorders causing NCPH involves the reduction of portal pressure by pharmacotherapy or portosystemic shunting, apart from prevention and treatment of complications of portal hypertension. PMID:25755321

  3. SU-F-T-486: A Simple Approach to Performing Light Versus Radiation Field Coincidence Quality Assurance Using An Electronic Portal Imaging Device (EPID)

    SciTech Connect

    Herchko, S; Ding, G

    2016-06-15

    Purpose: To develop an accurate, straightforward, and user-independent method for performing light versus radiation field coincidence quality assurance utilizing EPID images, a simple phantom made of readily-accessible materials, and a free software program. Methods: A simple phantom consisting of a blocking tray, graph paper, and high-density wire was constructed. The phantom was used to accurately set the size of a desired light field and imaged on the electronic portal imaging device (EPID). A macro written for use in ImageJ, a free image processing software, was then use to determine the radiation field size utilizing the high density wires on themore » phantom for a pixel to distance calibration. The macro also performs an analysis on the measured radiation field utilizing the tolerances recommended in the AAPM Task Group #142. To verify the accuracy of this method, radiochromic film was used to qualitatively demonstrate agreement between the film and EPID results, and an additional ImageJ macro was used to quantitatively compare the radiation field sizes measured both with the EPID and film images. Results: The results of this technique were benchmarked against film measurements, which have been the gold standard for testing light versus radiation field coincidence. The agreement between this method and film measurements were within 0.5 mm. Conclusion: Due to the operator dependency associated with tracing light fields and measuring radiation fields by hand when using film, this method allows for a more accurate comparison between the light and radiation fields with minimal operator dependency. Removing the need for radiographic or radiochromic film also eliminates a reoccurring cost and increases procedural efficiency.« less

  4. Linear array measurements of enhanced dynamic wedge and treatment planning system (TPS) calculation for 15 MV photon beam and comparison with electronic portal imaging device (EPID) measurements.

    PubMed

    Petrovic, Borislava; Grzadziel, Aleksandra; Rutonjski, Laza; Slosarek, Krzysztof

    2010-09-01

    Enhanced dynamic wedges (EDW) are known to increase drastically the radiation therapy treatment efficiency. This paper has the aim to compare linear array measurements of EDW with the calculations of treatment planning system (TPS) and the electronic portal imaging device (EPID) for 15 MV photon energy. The range of different field sizes and wedge angles (for 15 MV photon beam) were measured by the linear chamber array CA 24 in Blue water phantom. The measurement conditions were applied to the calculations of the commercial treatment planning system XIO CMS v.4.2.0 using convolution algorithm. EPID measurements were done on EPID-focus distance of 100 cm, and beam parameters being the same as for CA24 measurements. Both depth doses and profiles were measured. EDW linear array measurements of profiles to XIO CMS TPS calculation differ around 0.5%. Profiles in non-wedged direction and open field profiles practically do not differ. Percentage depth doses (PDDs) for all EDW measurements show the difference of not more than 0.2%, while the open field PDD is almost the same as EDW PDD. Wedge factors for 60 deg wedge angle were also examined, and the difference is up to 4%. EPID to linear array differs up to 5%. The implementation of EDW in radiation therapy treatments provides clinicians with an effective tool for the conformal radiotherapy treatment planning. If modelling of EDW beam in TPS is done correctly, a very good agreement between measurements and calculation is obtained, but EPID cannot be used for reference measurements.

  5. MO-FG-202-04: Gantry-Resolved Linac QA for VMAT: A Comprehensive and Efficient System Using An Electronic Portal Imaging Device

    SciTech Connect

    Zwan, B J; University of Newcastle, Newcastle, NSW; Barnes, M

    2016-06-15

    Purpose: To automate gantry-resolved linear accelerator (linac) quality assurance (QA) for volumetric modulated arc therapy (VMAT) using an electronic portal imaging device (EPID). Methods: A QA system for VMAT was developed that uses an EPID, frame-grabber assembly and in-house developed image processing software. The system relies solely on the analysis of EPID image frames acquired without the presence of a phantom. Images were acquired at 8.41 frames per second using a frame grabber and ancillary acquisition computer. Each image frame was tagged with a gantry angle from the linac’s on-board gantry angle encoder. Arc-dynamic QA plans were designed to assessmore » the performance of each individual linac component during VMAT. By analysing each image frame acquired during the QA deliveries the following eight machine performance characteristics were measured as a function of gantry angle: MLC positional accuracy, MLC speed constancy, MLC acceleration constancy, MLC-gantry synchronisation, beam profile constancy, dose rate constancy, gantry speed constancy, dose-gantry angle synchronisation and mechanical sag. All tests were performed on a Varian iX linear accelerator equipped with a 120 leaf Millennium MLC and an aS1000 EPID (Varian Medical Systems, Palo Alto, CA, USA). Results: Machine performance parameters were measured as a function of gantry angle using EPID imaging and compared to machine log files and the treatment plan. Data acquisition is currently underway at 3 centres, incorporating 7 treatment units, at 2 weekly measurement intervals. Conclusion: The proposed system can be applied for streamlined linac QA and commissioning for VMAT. The set of test plans developed can be used to assess the performance of each individual components of the treatment machine during VMAT deliveries as a function of gantry angle. The methodology does not require the setup of any additional phantom or measurement equipment and the analysis is fully automated to allow

  6. A novel method for patient exit and entrance dose prediction based on water equivalent path length measured with an amorphous silicon electronic portal imaging device.

    PubMed

    Kavuma, Awusi; Glegg, Martin; Metwaly, Mohamed; Currie, Garry; Elliott, Alex

    2010-01-21

    In vivo dosimetry is one of the quality assurance tools used in radiotherapy to monitor the dose delivered to the patient. Electronic portal imaging device (EPID) images for a set of solid water phantoms of varying thicknesses were acquired and the data fitted onto a quadratic equation, which relates the reduction in photon beam intensity to the attenuation coefficient and material thickness at a reference condition. The quadratic model is used to convert the measured grey scale value into water equivalent path length (EPL) at each pixel for any material imaged by the detector. For any other non-reference conditions, scatter, field size and MU variation effects on the image were corrected by relative measurements using an ionization chamber and an EPID. The 2D EPL is linked to the percentage exit dose table, for different thicknesses and field sizes, thereby converting the plane pixel values at each point into a 2D dose map. The off-axis ratio is corrected using envelope and boundary profiles generated from the treatment planning system (TPS). The method requires field size, monitor unit and source-to-surface distance (SSD) as clinical input parameters to predict the exit dose, which is then used to determine the entrance dose. The measured pixel dose maps were compared with calculated doses from TPS for both entrance and exit depth of phantom. The gamma index at 3% dose difference (DD) and 3 mm distance to agreement (DTA) resulted in an average of 97% passing for the square fields of 5, 10, 15 and 20 cm. The exit dose EPID dose distributions predicted by the algorithm were in better agreement with TPS-calculated doses than phantom entrance dose distributions.

  7. A novel method for patient exit and entrance dose prediction based on water equivalent path length measured with an amorphous silicon electronic portal imaging device

    NASA Astrophysics Data System (ADS)

    Kavuma, Awusi; Glegg, Martin; Metwaly, Mohamed; Currie, Garry; Elliott, Alex

    2010-01-01

    In vivo dosimetry is one of the quality assurance tools used in radiotherapy to monitor the dose delivered to the patient. Electronic portal imaging device (EPID) images for a set of solid water phantoms of varying thicknesses were acquired and the data fitted onto a quadratic equation, which relates the reduction in photon beam intensity to the attenuation coefficient and material thickness at a reference condition. The quadratic model is used to convert the measured grey scale value into water equivalent path length (EPL) at each pixel for any material imaged by the detector. For any other non-reference conditions, scatter, field size and MU variation effects on the image were corrected by relative measurements using an ionization chamber and an EPID. The 2D EPL is linked to the percentage exit dose table, for different thicknesses and field sizes, thereby converting the plane pixel values at each point into a 2D dose map. The off-axis ratio is corrected using envelope and boundary profiles generated from the treatment planning system (TPS). The method requires field size, monitor unit and source-to-surface distance (SSD) as clinical input parameters to predict the exit dose, which is then used to determine the entrance dose. The measured pixel dose maps were compared with calculated doses from TPS for both entrance and exit depth of phantom. The gamma index at 3% dose difference (DD) and 3 mm distance to agreement (DTA) resulted in an average of 97% passing for the square fields of 5, 10, 15 and 20 cm. The exit dose EPID dose distributions predicted by the algorithm were in better agreement with TPS-calculated doses than phantom entrance dose distributions.

  8. Comparison of low‐dose, half‐rotation, cone‐beam CT with electronic portal imaging device for registration of fiducial markers during prostate radiotherapy

    PubMed Central

    Wee, Leonard; Hackett, Sara Lyons; Jones, Andrew; Lim, Tee Sin; Harper, Christopher Stirling

    2013-01-01

    This study evaluated the agreement of fiducial marker localization between two modalities — an electronic portal imaging device (EPID) and cone‐beam computed tomography (CBCT) — using a low‐dose, half‐rotation scanning protocol. Twenty‐five prostate cancer patients with implanted fiducial markers were enrolled. Before each daily treatment, EPID and half‐rotation CBCT images were acquired. Translational shifts were computed for each modality and two marker‐matching algorithms, seed‐chamfer and grey‐value, were performed for each set of CBCT images. The localization offsets, and systematic and random errors from both modalities were computed. Localization performances for both modalities were compared using Bland‐Altman limits of agreement (LoA) analysis, Deming regression analysis, and Cohen's kappa inter‐rater analysis. The differences in the systematic and random errors between the modalities were within 0.2 mm in all directions. The LoA analysis revealed a 95% agreement limit of the modalities of 2 to 3.5 mm in any given translational direction. Deming regression analysis demonstrated that constant biases existed in the shifts computed by the modalities in the superior–inferior (SI) direction, but no significant proportional biases were identified in any direction. Cohen's kappa analysis showed good agreement between the modalities in prescribing translational corrections of the couch at 3 and 5 mm action levels. Images obtained from EPID and half‐rotation CBCT showed acceptable agreement for registration of fiducial markers. The seed‐chamfer algorithm for tracking of fiducial markers in CBCT datasets yielded better agreement than the grey‐value matching algorithm with EPID‐based registration. PACS numbers: 87.55.km, 87.55.Qr PMID:23835391

  9. SU-F-P-36: Automation of Linear Accelerator Star Shot Measurement with Advanced XML Scripting and Electronic Portal Imaging Device

    SciTech Connect

    Nguyen, N; Knutson, N; Schmidt, M

    Purpose: To verify a method used to automatically acquire jaw, MLC, collimator and couch star shots for a Varian TrueBeam linear accelerator utilizing Developer Mode and an Electronic Portal Imaging Device (EPID). Methods: An XML script was written to automate motion of the jaws, MLC, collimator and couch in TrueBeam Developer Mode (TBDM) to acquire star shot measurements. The XML script also dictates MV imaging parameters to facilitate automatic acquisition and recording of integrated EPID images. Since couch star shot measurements cannot be acquired using a combination of EPID and jaw/MLC collimation alone due to a fixed imager geometry, amore » method utilizing a 5mm wide steel ruler placed on the table and centered within a 15×15cm2 open field to produce a surrogate of the narrow field aperture was investigated. Four individual star shot measurements (X jaw, Y jaw, MLC and couch) were obtained using our proposed as well as traditional film-based method. Integrated EPID images and scanned measurement films were analyzed and compared. Results: Star shot (X jaw, Y jaw, MLC and couch) measurements were obtained in a single 5 minute delivery using the TBDM XML script method compared to 60 minutes for equivalent traditional film measurements. Analysis of the images and films demonstrated comparable isocentricity results, agreeing within 0.3mm of each other. Conclusion: The presented automatic approach of acquiring star shot measurements using TBDM and EPID has proven to be more efficient than the traditional film approach with equivalent results.« less

  10. Dosimetry in radiotherapy using a-Si EPIDs: Systems, methods, and applications focusing on 3D patient dose estimation

    NASA Astrophysics Data System (ADS)

    McCurdy, B. M. C.

    2013-06-01

    An overview is provided of the use of amorphous silicon electronic portal imaging devices (EPIDs) for dosimetric purposes in radiation therapy, focusing on 3D patient dose estimation. EPIDs were originally developed to provide on-treatment radiological imaging to assist with patient setup, but there has also been a natural interest in using them as dosimeters since they use the megavoltage therapy beam to form images. The current generation of clinically available EPID technology, amorphous-silicon (a-Si) flat panel imagers, possess many characteristics that make them much better suited to dosimetric applications than earlier EPID technologies. Features such as linearity with dose/dose rate, high spatial resolution, realtime capability, minimal optical glare, and digital operation combine with the convenience of a compact, retractable detector system directly mounted on the linear accelerator to provide a system that is well-suited to dosimetric applications. This review will discuss clinically available a-Si EPID systems, highlighting dosimetric characteristics and remaining limitations. Methods for using EPIDs in dosimetry applications will be discussed. Dosimetric applications using a-Si EPIDs to estimate three-dimensional dose in the patient during treatment will be overviewed. Clinics throughout the world are implementing increasingly complex treatments such as dynamic intensity modulated radiation therapy and volumetric modulated arc therapy, as well as specialized treatment techniques using large doses per fraction and short treatment courses (ie. hypofractionation and stereotactic radiosurgery). These factors drive the continued strong interest in using EPIDs as dosimeters for patient treatment verification.

  11. Noncirrhotic portal hypertension.

    PubMed

    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.

  12. Pediatric portal hypertension

    PubMed Central

    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

  13. TH-AB-202-02: Real-Time Verification and Error Detection for MLC Tracking Deliveries Using An Electronic Portal Imaging Device

    SciTech Connect

    J Zwan, B; Central Coast Cancer Centre, Gosford, NSW; Colvill, E

    2016-06-15

    Purpose: The added complexity of the real-time adaptive multi-leaf collimator (MLC) tracking increases the likelihood of undetected MLC delivery errors. In this work we develop and test a system for real-time delivery verification and error detection for MLC tracking radiotherapy using an electronic portal imaging device (EPID). Methods: The delivery verification system relies on acquisition and real-time analysis of transit EPID image frames acquired at 8.41 fps. In-house software was developed to extract the MLC positions from each image frame. Three comparison metrics were used to verify the MLC positions in real-time: (1) field size, (2) field location and, (3)more » field shape. The delivery verification system was tested for 8 VMAT MLC tracking deliveries (4 prostate and 4 lung) where real patient target motion was reproduced using a Hexamotion motion stage and a Calypso system. Sensitivity and detection delay was quantified for various types of MLC and system errors. Results: For both the prostate and lung test deliveries the MLC-defined field size was measured with an accuracy of 1.25 cm{sup 2} (1 SD). The field location was measured with an accuracy of 0.6 mm and 0.8 mm (1 SD) for lung and prostate respectively. Field location errors (i.e. tracking in wrong direction) with a magnitude of 3 mm were detected within 0.4 s of occurrence in the X direction and 0.8 s in the Y direction. Systematic MLC gap errors were detected as small as 3 mm. The method was not found to be sensitive to random MLC errors and individual MLC calibration errors up to 5 mm. Conclusion: EPID imaging may be used for independent real-time verification of MLC trajectories during MLC tracking deliveries. Thresholds have been determined for error detection and the system has been shown to be sensitive to a range of delivery errors.« less

  14. SU-F-T-230: A Simple Method to Assess Accuracy of Dynamic Wave Arc Irradiation Using An Electronic Portal Imaging Device and Log Files

    SciTech Connect

    Hirashima, H; Miyabe, Y; Yokota, K

    2016-06-15

    Purpose: The Dynamic Wave Arc (DWA) technique, where the multi-leaf collimator (MLC) and gantry/ring move simultaneously in a predefined non-coplanar trajectory, has been developed on the Vero4DRT. The aim of this study is to develop a simple method for quality assurance of DWA delivery using an electronic portal imaging device (EPID) measurements and log files analysis. Methods: The Vero4DRT has an EPID on the beam axis, the resolution of which is 0.18 mm/pixel at the isocenter plane. EPID images were acquired automatically. To verify the detection accuracy of the MLC position by EPID images, the MLC position with intentional errorsmore » was assessed. Tests were designed considering three factors: (1) accuracy of the MLC position (2) dose output consistency with variable dose rate (160–400 MU/min), gantry speed (2.4–6°/s), ring speed (0.5–2.5°/s), and (3) MLC speed (1.6–4.2 cm/s). All the patterns were delivered to the EPID and compared with those obtained with a stationary radiation beam with a 0° gantry angle. The irradiation log, including the MLC position and gantry/ring angle, were recorded simultaneously. To perform independent checks of the machine accuracy, the MLC position and gantry/ring angle position were assessed using log files. Results: 0.1 mm intentional error can be detected by the EPID, which is smaller than the EPID pixel size. The dose outputs with different conditions of the dose rate and gantry/ring speed and MLC speed showed good agreement, with a root mean square (RMS) error of 0.76%. The RMS error between the detected and recorded data were 0.1 mm for the MLC position, 0.12° for the gantry angle, and 0.07° for the ring angle. Conclusion: The MLC position and dose outputs in variable conditions during DWA irradiation can be easily detected using EPID measurements and log file analysis. The proposed method is useful for routine verification. This research is (partially) supported by the Practical Research for Innovative

  15. SU-C-201-05: Silicon Array Dosimeter in Situ with Electronic Portal Image Device for Simultaneous Transit Dose and Image Verification in Radiotherapy

    SciTech Connect

    Deshpande, S; Alhujaili, S; Vial, P

    Purpose: To investigate an Electronic Portal Imaging Device (EPID) coupled to a 2D array dosimeter to provide simultaneous imaging and dose verification. Methods: The novel dual detector configuration comprised of a 2D diode array dosimeter, referred to as a Magic Plate (MP) placed directly on a standard EPID. Dose response of the MP was evaluated by measuring the detector’s response with respect to off-axis position and field size with 30 cm of solid water (SW) acting as a transit object in the beam. Measurements were performed with 3, 5, 10 and 15 mm SW build-up and compared to 2D ionisationmore » chamber array (ICA) measurements and the PinnacleTM treatment planning system (TPS) at a source to detector distance of 150 cm with a 6 MV beam. Clinical dosimetric performance was evaluated by measuring a number of intensity-modulated radiation therapy (IMRT) beams in transit geometry. Imaging performance of the EPID was quantified by measuring the contrast-to-noise ratio (CNR) and spatial resolution. Images of a Rando phantom were used for qualitative assessment. Results: Measured MP off-axis and field size response agreed within 2% of TPS and ICA responses when measured using 15 mm SW build-up. Clinical IMRT beams had gamma pass rates of ≥95% at 3%/3mm criteria. Measured CNR and spatial resolution (f50) were 264.96, 210.6, and 0.41, 0.40 with build-up of 5 and 15 mm respectively for the dual detector configuration. CNR and spatial resolution of 643.9 and 0.41 were measured for standard EPID. CNR was quantitatively worse in the dual detector configuration. Differences in imaging performance were not visible in a qualitative assessment using a Rando phantom. Conclusion: Combining a prototype MP 2D dosimeter with a conventional EPID did not significantly detract from the performance of either device and has the potential for simultaneous on-line patient transit dosimetry and image assessment in radiation therapy. Cancer Institute NSW Australia(Research Equipment

  16. WE-D-BRA-03: Four-Dimensional Dose Reconstruction Through Retrospective Phase Determination Using Cine Images of Electronic Portal Imaging Device

    SciTech Connect

    Yoon, J; Jung, J; Yi, B

    2015-06-15

    Purpose: To test a method to reconstruct a four-dimensional (4D) dose distribution using the correlation of pre-calculated 4D electronic portal imaging device (EPID) images and measured cine-EPID images. Methods: 1. A phantom designed to simulate a tumor in lung (a polystyrene block with 3.0 cm diameter embedded in cork) was placed on a sinusoidally moving platform with 2 cm amplitude and 4 sec/cycle. Ten-phase 4D CT images were acquired for treatment planning and dose reconstruction. A 6MV photon beam was irradiated on the phantom with static (field size=5×8.5 cm{sup 2}) and dynamic fields (sliding windows, 10×10 cm{sup 2}, X1 MLCmore » closing in parallel with the tumor movement). 2. 4D and 3D doses were calculated forwardly on PTV (1 cm margin). 3. Dose images on EPID under the fields were calculated for 10 phases. 4. Cine EPID images were acquired during irradiation. 5. Their acquisition times were correlated to the phases of the phantom at which irradiation occurred by inter-comparing calculated “reference” EPID images with measured images (2D gamma comparison). For the dynamic beam, the tumor was hidden under MLCs during a portion of irradiation time; the correlation performed when the tumor was visible was extrapolated. 6. Dose for each phase was reconstructed on the 4D CT images and summed over all phases. The summation was compared with forwardly calculated 4D and 3D dose distributions. Monte Carlo methods were used for all calculations. Results: For the open and dynamic beams, the 4D reconstructed doses showed the pass rates of 92.7 % and 100 %, respectively, at the isocenter plane given 3% / 3 mm criteria. The better agreement of the dynamic beam was from its dose gradient which blurred the otherwise sharp difference between forward and reconstructed doses. This also contributed slightly better agreement in DVH of PTV. Conclusion: The feasibility of 4D reconstruction was demonstrated.« less

  17. SU-G-TeP4-03: A Multileaf Collimator Calibration and Quality Assurance Technique Using An Electronic Portal Imaging Device

    SciTech Connect

    Lebron, S; Yan, G; Li, J

    2016-06-15

    Purpose: To develop an accurate and quick multileaf collimator (MLC) calibration and quality assurance technique using an electronic portal imaging device (EPID) Methods: The MLC models used include the MLCi and Agility (Elekta Ltd). This technique consists of two 22(L)x10(W) cm{sup 2} fields with 0{sup 0} and 180{sup 0} collimator angles centered to an offset EPID. The MLC opening is estimated by calculating the profile at the image’s center in the image’s horizontal direction. Scans in the image’s vertical direction were calculated every 20 pixels in the inner 70% of estimated MLC opening. The profiles’ edges were fitted with linearmore » equations to determine the image’s rotation angle. Then, crossline profiles were scanned at the center of each leaf taking into account the leaf’s width at isocenter and the rotation angle. The profiles’ edges determine the location of the leaves’ edges and these were subtracted from the reference leaf’s position in order to determine the relative leaf offsets. The edge location of all profiles was determined by using the parameterized gradient of the penumbra region. The technique was tested against an established diode array-based method, and for different MLC systems, patterns, gantry angles, days, energies, beam modalities and MLC openings. Results: The differences between the proposed and established methods were 0.26±0.19mm. The leaf offsets’ deviation was <0.3mm (5 months period). For pattern fields, the differences between predetermined and calculated offsets were 0.18±0.18mm. The leaf offset deviation of measurements with different energies and MLC openings were <0.1mm and <0.3mm, respectively. The differences between offsets of FF and FFF beams were 0.01±0.02mm (<0.07mm). The differences between the offsets at different gantry angles were 0.08±0.15mm. Conclusion: The proposed method proved to be accurate and efficient in calculating the relative leaf offsets. Parameterized field edge is

  18. Roadside Tracker Portal-less Portal Monitor

    SciTech Connect

    Ziock, Klaus-Peter; Cheriyadat, Anil M.; Bradley, Eric Craig

    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.

  19. Patient web portals, disease management, and primary prevention

    PubMed Central

    Coughlin, Steven S; Prochaska, Judith J; Williams, Lovoria B; Besenyi, Gina M; Heboyan, Vahé; Goggans, D Stephen; Yoo, Wonsuk; De Leo, Gianluca

    2017-01-01

    Background Efforts aimed at health care reform and continued advances in information technologies have prompted interest among providers and researchers in patient web portals. Patient web portals are password-protected online websites that offer the patients 24-hour access to personal health information from anywhere with an Internet connection. Methods This article, which is based upon bibliographic searches in PubMed, reviews important developments in web portals for primary and secondary disease prevention, including patient web portals tethered to electronic medical records, disease-specific portals, health disparities, and health-related community web portals. Results Although findings have not been uniformly positive, several studies of the effectiveness of health care system patient portals in chronic disease management have shown promising results with regard to patient outcomes. Patient web portals have also shown promising results in increasing adherence with screening recommendations. Racial and ethnic minorities, younger persons, and patients who are less educated or have lower health literacy have been found to be less likely to use patient portals. Conclusion Additional studies are needed of the utility and effectiveness of different elements of web portals for different patient populations. This should include additional diseases and health topics such as smoking cessation and weight management. PMID:28435342

  20. Patient web portals, disease management, and primary prevention.

    PubMed

    Coughlin, Steven S; Prochaska, Judith J; Williams, Lovoria B; Besenyi, Gina M; Heboyan, Vahé; Goggans, D Stephen; Yoo, Wonsuk; De Leo, Gianluca

    2017-01-01

    Efforts aimed at health care reform and continued advances in information technologies have prompted interest among providers and researchers in patient web portals. Patient web portals are password-protected online websites that offer the patients 24-hour access to personal health information from anywhere with an Internet connection. This article, which is based upon bibliographic searches in PubMed, reviews important developments in web portals for primary and secondary disease prevention, including patient web portals tethered to electronic medical records, disease-specific portals, health disparities, and health-related community web portals. Although findings have not been uniformly positive, several studies of the effectiveness of health care system patient portals in chronic disease management have shown promising results with regard to patient outcomes. Patient web portals have also shown promising results in increasing adherence with screening recommendations. Racial and ethnic minorities, younger persons, and patients who are less educated or have lower health literacy have been found to be less likely to use patient portals. Additional studies are needed of the utility and effectiveness of different elements of web portals for different patient populations. This should include additional diseases and health topics such as smoking cessation and weight management.

  1. SU-E-T-582: On-Line Dosimetric Verification of Respiratory Gated Volumetric Modulated Arc Therapy Using the Electronic Portal Imaging Device

    SciTech Connect

    Schaly, B; Gaede, S; Department of Medical Biophysics, Western University, London, ON

    2015-06-15

    Purpose: To investigate the clinical utility of on-line verification of respiratory gated VMAT dosimetry during treatment. Methods: Portal dose images were acquired during treatment in integrated mode on a Varian TrueBeam (v. 1.6) linear accelerator for gated lung and liver patients that used flattening filtered beams. The source to imager distance (SID) was set to 160 cm to ensure imager clearance in case the isocenter was off midline. Note that acquisition of integrated images resulted in no extra dose to the patient. Fraction 1 was taken as baseline and all portal dose images were compared to that of the baseline,more » where the gamma comparison and dose difference were used to measure day-to-day exit dose variation. All images were analyzed in the Portal Dosimetry module of Aria (v. 10). The portal imager on the TrueBeam was calibrated by following the instructions for dosimetry calibration in service mode, where we define 1 calibrated unit (CU) equal to 1 Gy for 10×10 cm field size at 100 cm SID. This reference condition was measured frequently to verify imager calibration. Results: The gamma value (3%, 3 mm, 5% threshold) ranged between 92% and 100% for the lung and liver cases studied. The exit dose can vary by as much as 10% of the maximum dose for an individual fraction. The integrated images combined with the information given by the corresponding on-line soft tissue matched cone-beam computed tomography (CBCT) images were useful in explaining dose variation. For gated lung treatment, dose variation was mainly due to the diaphragm position. For gated liver treatment, the dose variation was due to both diaphragm position and weight loss. Conclusion: Integrated images can be useful in verifying dose delivery consistency during respiratory gated VMAT, although the CBCT information is needed to explain dose differences due to anatomical changes.« less

  2. 3. East portal of Tunnel 39, view to west with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. East portal of Tunnel 39, view to west with east portal of Tunnel 38 (HAER CA-211) visible in distance, 135mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 39, Milepost 180.95, Cisco, Placer County, CA

  3. Portal Vein Stenting for Portal Biliopathy with Jaundice

    SciTech Connect

    Hyun, Dongho, E-mail: mesentery@naver.com; Park, Kwang Bo, E-mail: kbjh.park@samsung.com; Lim, Seong Joo

    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.

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

    PubMed

    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.

  5. Portal Vein Thrombosis

    PubMed Central

    Chawla, Yogesh K.; Bodh, Vijay

    2015-01-01

    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. PMID:25941431

  6. Classification of cryo electron microscopy images, noisy tomographic images recorded with unknown projection directions, by simultaneously estimating reconstructions and application to an assembly mutant of Cowpea Chlorotic Mottle Virus and portals of the bacteriophage P22

    NASA Astrophysics Data System (ADS)

    Lee, Junghoon; Zheng, Yili; Yin, Zhye; Doerschuk, Peter C.; Johnson, John E.

    2010-08-01

    Cryo electron microscopy is frequently used on biological specimens that show a mixture of different types of object. Because the electron beam rapidly destroys the specimen, the beam current is minimized which leads to noisy images (SNR substantially less than 1) and only one projection image per object (with an unknown projection direction) is collected. For situations where the objects can reasonably be described as coming from a finite set of classes, an approach based on joint maximum likelihood estimation of the reconstruction of each class and then use of the reconstructions to label the class of each image is described and demonstrated on two challenging problems: an assembly mutant of Cowpea Chlorotic Mottle Virus and portals of the bacteriophage P22.

  7. Climate change portal established

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2011-12-01

    The World Bank has developed a Climate Change Knowledge Portal as a kind of “onestop shop” for climate-related information, data, and tools. The portal provides access to global, regional, and national data and reports with an aim to providing a resource for learning about climate information and increasing knowledge on climate change—related actions. For more information, see http://sdwebx.worldbank.org/climateportal/.

  8. [Idiopathic portal hypertension].

    PubMed

    Orozco, H; Takahashi, T; García-Tsao, G; Mercado, M A; Diliz, H; Hernández-Ortiz, J

    1991-01-01

    Patients with portal hypertension without a demonstrable cause have been reported in the literature under several different terms, such as tropical splenomegaly, phlebosclerosis, obliterative portal venopathy of the liver, hepatoportal sclerosis, noncirrhotic portal fibrosis and idiopathic portal hypertension (IPH). Such patients have been described worldwide, with a greater frequency in India and Japan. The etiology of IPH is still unknown, although some of the theories that have been proposed are: exposure to toxic substances or drugs, relationship with the hepatitis-B virus, immunologic abnormalities, systemic or intra-abdominal infections and clotting abnormalities. The main histopathologic findings are periportal fibrosis, obliteration of small portal veins and sclerosis of the interhepatic portal system. Although these abnormalities could be secondary to portal hypertension, it has been proposed that the vascular changes are the primary event that leads to portal hypertension. The site of increased resistance in IPH is found at the presinusoidal level with some component at the sinusoidal and postsinusoidal level. The main symptoms and signs in IPH are upper gastrointestinal tract bleeding secondary to esophago-gastric varices, symptoms related to anemia, and splenomegaly. The long-term prognosis for patients with IPH is better than for cirrhotic patients, with a 77% survival at ten years. Variceal bleeding is the main cause of death, and some treatment to prevent bleeding or its recurrence is warranted. Although no comparative trial has been performed in IPH patients, the surgical management could be the first choice for elective treatment in these patient without liver failure, because of the high re-bleeding rates with chronic sclerotherapy. Pharmacologic management could be considered for prophylactic treatment of these patients.

  9. Regulations.gov Federal Regulatory Portal

    ERIC Educational Resources Information Center

    Ashlin, John; Davis, Richard; Dalecky, Selene; Grasso, Richard; LaPlant, Lisa; Morales, Oscar; Nelson, Jennifer; White, Michael; Whitt, Sharon A.

    2004-01-01

    The Regulations.gov Online Rulemaking Project is 1 of the 24 e-Government Initiatives on the President's Management Agenda (PMA), which was announced by the White House in 2001. The Regulations.gov Web site is the central electronic rulemaking portal for the federal government. Through a single Web site, citizens can search, view, and comment on…

  10. Biology of portal hypertension.

    PubMed

    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.

  11. 4. West portal of Tunnel 5, view to the northwest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. West portal of Tunnel 5, view to the northwest from within the mudshed, 135mm lens with electronic flash fill. - Southern Pacific Railroad Natron Cutoff, Tunnel 5, Milepost 545.2, McCredie Springs, Lane County, OR

  12. 6. Detail, vertical guides adjacent to east portal of Tunnel ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Detail, vertical guides adjacent to east portal of Tunnel 28, view to southwest, 135mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 28, Milepost 134.75, Applegate, Placer County, CA

  13. 7. Detail, machinery shed atop east portal of Tunnel 28, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail, machinery shed atop east portal of Tunnel 28, showing shaft and pulley system, 210mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 28, Milepost 134.75, Applegate, Placer County, CA

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

    PubMed

    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.

  15. The NOAO NVO Portal

    NASA Astrophysics Data System (ADS)

    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).

  16. Pregnancy with Portal Hypertension

    PubMed Central

    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

  17. Elevation, west portal. Sign on portal reads Watson Mill Bridge, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Elevation, west portal. Sign on portal reads Watson Mill Bridge, est. 1885. - Watson Mill Bridge, Spanning South Fork Broad River, Watson Mill Road, Watson Mill Bridge State Park, Comer, Madison County, GA

  18. Target detection portal

    DOEpatents

    Linker, Kevin L.; Brusseau, Charles A.

    2002-01-01

    A portal apparatus for screening persons or objects for the presence of trace amounts of target substances such as explosives, narcotics, radioactive materials, and certain chemical materials. The portal apparatus can have a one-sided exhaust for an exhaust stream, an interior wall configuration with a concave-shape across a horizontal cross-section for each of two facing sides to result in improved airflow and reduced washout relative to a configuration with substantially flat parallel sides; air curtains to reduce washout; ionizing sprays to collect particles bound by static forces, as well as gas jet nozzles to dislodge particles bound by adhesion to the screened person or object. The portal apparatus can be included in a detection system with a preconcentrator and a detector.

  19. Ten Keys to the Portal

    ERIC Educational Resources Information Center

    Schaffhauser, Dian

    2011-01-01

    Successful web portals help users stay informed, in touch, and up to speed. They are also a telling window into the efficiency of one's institution. To develop a cutting-edge portal takes planning, communication, and research. In this article, the author presents and discusses 10 keys to portal success: (1) make critical info visible; (2) make the…

  20. Comparative performance evaluation of a new a-Si EPID that exceeds quad high-definition resolution.

    PubMed

    McConnell, Kristen A; Alexandrian, Ara; Papanikolaou, Niko; Stathakis, Sotiri

    2018-01-01

    Electronic portal imaging devices (EPIDs) are an integral part of the radiation oncology workflow for treatment setup verification. Several commercial EPID implementations are currently available, each with varying capabilities. To standardize performance evaluation, Task Group Report 58 (TG-58) and TG-142 outline specific image quality metrics to be measured. A LinaTech Image Viewing System (IVS), with the highest commercially available pixel matrix (2688x2688 pixels), was independently evaluated and compared to an Elekta iViewGT (1024x1024 pixels) and a Varian aSi-1000 (1024x768 pixels) using a PTW EPID QC Phantom. The IVS, iViewGT, and aSi-1000 were each used to acquire 20 images of the PTW QC Phantom. The QC phantom was placed on the couch and aligned at isocenter. The images were exported and analyzed using the epidSoft image quality assurance (QA) software. The reported metrics were signal linearity, isotropy of signal linearity, signal-tonoise ratio (SNR), low contrast resolution, and high-contrast resolution. These values were compared between the three EPID solutions. Computed metrics demonstrated comparable results between the EPID solutions with the IVS outperforming the aSi-1000 and iViewGT in the low and high-contrast resolution analysis. The performance of three commercial EPID solutions have been quantified, evaluated, and compared using results from the PTW QC Phantom. The IVS outperformed the other panels in low and high-contrast resolution, but to fully realize the benefits of the IVS, the selection of the monitor on which to view the high-resolution images is important to prevent down sampling and visual of resolution.

  1. Earthdata Developer Portal

    NASA Technical Reports Server (NTRS)

    Plofchan, Peter; Reese, Mark; Siarto, Jeff; Clark, Nathan

    2016-01-01

    The Earthdata Developer Portal provides clear paths to get you started with core EOSDIS applications. Each path is accompanied by an overview page that explains the goal of the path and a short overview of each element along with links for detailed documentation of each component.

  2. The Learning Portal

    ERIC Educational Resources Information Center

    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…

  3. Using Patient Portals to Increase Engagement in Patients with Cancer.

    PubMed

    Rodriguez, Elizabeth S

    2018-05-01

    To review patient portals which serve as a tool for patient engagement by increasing access to electronic health care information and expanding ways to communicate with health care providers. Reviews of the literature and first-hand experience. Meaningful Use requirements propelled the design and development of patient portals in recent years. Patient engagement in oncology can improve quality of life and outcomes. Oncology nurses facilitate patient adoption of patient portals and support usage. Patient education helps manage communication expectations and understanding of online medical information. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. 77 FR 59670 - Electronic Filing of H-2A and H-2B Labor Certification Applications Through the iCERT Visa Portal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ... DEPARTMENT OF LABOR Employment and Training Administration Electronic Filing of H-2A and H-2B... certification applications under the H-2A and H-2B visa programs through the Department of Labor's (Department... will be able to submit H-2B applications electronically beginning on October 15, 2012, and H-2A...

  5. 1. East portal of Tunnel 4, view to west with ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. East portal of Tunnel 4, view to west with east portal of Tunnel 38 (HAER CA-211) visible in distance, 135mm lens with electronic flash fill. This tunnel was photographed to provide context, because even though somewhat enlarged, it illustrates the nature of the unlined hard rock tunnels typical of the original Central Pacific construction in 1868. - Central Pacific Transcontinental Railroad, Tunnel No. 4, Milepost 180.95, Cisco, Placer County, CA

  6. 8. Detail, east portal of Tunnel 41 inside Snowshed 33, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Detail, east portal of Tunnel 41 inside Snowshed 33, view to west-northwest, 135mm lens with electronic flash fill. The tiny white dot visible in the darkness of the tunnel is the west portal, two miles distant. The heavy steel beams carrying the concrete roof panels of the snowshed appear to be reused bridge girders. - Central Pacific Transcontinental Railroad, Tunnel No. 41, Milepost 193.3, Donner, Placer County, CA

  7. Sensitivity of an Elekta iView GT a-Si EPID model to delivery errors for pre-treatment verification of IMRT fields.

    PubMed

    Herwiningsih, Sri; Hanlon, Peta; Fielding, Andrew

    2014-12-01

    A Monte Carlo model of an Elekta iViewGT amorphous silicon electronic portal imaging device (a-Si EPID) has been validated for pre-treatment verification of clinical IMRT treatment plans. The simulations involved the use of the BEAMnrc and DOSXYZnrc Monte Carlo codes to predict the response of the iViewGT a-Si EPID model. The predicted EPID images were compared to the measured images obtained from the experiment. The measured EPID images were obtained by delivering a photon beam from an Elekta Synergy linac to the Elekta iViewGT a-Si EPID. The a-Si EPID was used with no additional build-up material. Frame averaged EPID images were acquired and processed using in-house software. The agreement between the predicted and measured images was analyzed using the gamma analysis technique with acceptance criteria of 3 %/3 mm. The results show that the predicted EPID images for four clinical IMRT treatment plans have a good agreement with the measured EPID signal. Three prostate IMRT plans were found to have an average gamma pass rate of more than 95.0 % and a spinal IMRT plan has the average gamma pass rate of 94.3 %. During the period of performing this work a routine MLC calibration was performed and one of the IMRT treatments re-measured with the EPID. A change in the gamma pass rate for one field was observed. This was the motivation for a series of experiments to investigate the sensitivity of the method by introducing delivery errors, MLC position and dosimetric overshoot, into the simulated EPID images. The method was found to be sensitive to 1 mm leaf position errors and 10 % overshoot errors.

  8. Verification of quality parameters for portal images in radiotherapy.

    PubMed

    Pesznyák, Csilla; Polgár, István; Weisz, Csaba; Király, Réka; Zaránd, Pál

    2011-03-01

    The purpose of the study was to verify different values of quality parameters of portal images in radiotherapy. We investigated image qualities of different field verification systems. Four EPIDs (Siemens OptiVue500aSi(®), Siemens BeamView Plus(®), Elekta iView(®) and Varian PortalVision™) were investigated with the PTW EPID QC PHANTOM(®) and compared with two portal film systems (Kodak X-OMAT(®) cassette with Kodak X-OMAT V(®) film and Kodak EC-L Lightweight(®) cassette with Kodak Portal Localisation ReadyPack(®) film). A comparison of the f50 and f25 values of the modulation transfer functions (MTFs) belonging to each of the systems revealed that the amorphous silicon EPIDs provided a slightly better high contrast resolution than the Kodak Portal Localisation ReadyPack(®) film with the EC-L Lightweight(®) cassette. The Kodak X-OMAT V(®) film gave a poor low contrast resolution: from the existing 27 holes only 9 were detectable. On the base of physical characteristics, measured in this work, the authors suggest the use of amorphous-silicon EPIDs producing the best image quality. Parameters of the EPIDs with scanning liquid ionisation chamber (SLIC) were very stable. The disadvantage of older versions of EPIDs like SLIC and VEPID is a poor DICOM implementation, and the modulation transfer function (MTF) values (f50 and f25) are less than that of aSi detectors.

  9. Opto-electronic properties of P-doped nc-Si-QD/a-SiC:H thin films as foundation layer for all-Si solar cells in superstrate configuration

    NASA Astrophysics Data System (ADS)

    Kar, Debjit; Das, Debajyoti

    2016-07-01

    With the advent of nc-Si solar cells having improved stability, the efficient growth of nc-Si i-layer of the top cell of an efficient all-Si solar cell in the superstrate configuration prefers nc-Si n-layer as its substrate. Accordingly, a wide band gap and high conducting nc-Si alloy material is a basic requirement at the n-layer. Present investigation deals with the development of phosphorous doped n-type nanocrystalline silicon quantum dots embedded in hydrogenated amorphous silicon carbide (nc-Si-QD/a-SiC:H) hetero-structure films, wherein the optical band gap can be widened by the presence of Si-C bonds in the amorphous matrix and the embedded high density tiny nc-Si-QDs could provide high electrical conductivity, particularly in P-doped condition. The nc-Si-QDs simultaneously facilitate further widening of the optical band gap by virtue of the associated quantum confinement effect. A complete investigation has been made on the electrical transport phenomena involving charge transfer by tunneling and thermionic emission prevailing in n-type nc-Si-QD/a-SiC:H thin films. Their correlation with different phases of the specific heterostructure has been carried out for detailed understanding of the material, in order to improve its device applicability. The n-type nc-Si-QD/a-SiC:H films exhibit a thermally activated electrical transport above room temperature and multi-phonon hopping (MPH) below room temperature, involving defects in the amorphous phase and the grain-boundary region. The n-type nc-Si-QD/a-SiC:H films grown at ˜300 °C, demonstrating wide optical gap ˜1.86-1.96 eV and corresponding high electrical conductivity ˜4.5 × 10-1-1.4 × 10-2 S cm-1, deserve to be an effective foundation layer for the top nc-Si sub-cell of all-Si solar cells in n-i-p structure with superstrate configuration.

  10. Opto-electronic properties of P-doped nc-Si–QD/a-SiC:H thin films as foundation layer for all-Si solar cells in superstrate configuration

    SciTech Connect

    Kar, Debjit; Das, Debajyoti, E-mail: erdd@iacs.res.in

    2016-07-14

    With the advent of nc-Si solar cells having improved stability, the efficient growth of nc-Si i-layer of the top cell of an efficient all-Si solar cell in the superstrate configuration prefers nc-Si n-layer as its substrate. Accordingly, a wide band gap and high conducting nc-Si alloy material is a basic requirement at the n-layer. Present investigation deals with the development of phosphorous doped n-type nanocrystalline silicon quantum dots embedded in hydrogenated amorphous silicon carbide (nc-Si–QD/a-SiC:H) hetero-structure films, wherein the optical band gap can be widened by the presence of Si–C bonds in the amorphous matrix and the embedded high densitymore » tiny nc-Si–QDs could provide high electrical conductivity, particularly in P-doped condition. The nc-Si–QDs simultaneously facilitate further widening of the optical band gap by virtue of the associated quantum confinement effect. A complete investigation has been made on the electrical transport phenomena involving charge transfer by tunneling and thermionic emission prevailing in n-type nc-Si–QD/a-SiC:H thin films. Their correlation with different phases of the specific heterostructure has been carried out for detailed understanding of the material, in order to improve its device applicability. The n-type nc-Si–QD/a-SiC:H films exhibit a thermally activated electrical transport above room temperature and multi-phonon hopping (MPH) below room temperature, involving defects in the amorphous phase and the grain-boundary region. The n-type nc-Si–QD/a-SiC:H films grown at ∼300 °C, demonstrating wide optical gap ∼1.86–1.96 eV and corresponding high electrical conductivity ∼4.5 × 10{sup −1}–1.4 × 10{sup −2} S cm{sup −1}, deserve to be an effective foundation layer for the top nc-Si sub-cell of all-Si solar cells in n-i-p structure with superstrate configuration.« less

  11. Portal Annular Pancreas

    PubMed Central

    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

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

    PubMed

    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.

  13. Transjugular Portal Venous Stenting in Inflammatory Extrahepatic Portal Vein Stenosis

    SciTech Connect

    Schaible, Rolf; Textor, Jochen; Decker, Pan

    2002-12-15

    We report the case of a 37-year-old man with necrotizing pancreatitis associated with inflammatory extrahepatic portal vein stenosis and progressive ascites. Four months after the acute onset, when no signs of infection were present, portal decompression was performed to treat refractory ascites. Transjugulartranshepatic venoplasty failed to dilate the stenosis in the extrahepatic portion of the portal vein sufficiently. Therefore a Wallstent was implanted, resulting in almost normal diameter of the vessel. In follow-up imaging studies the stent and the portal vein were still patent 12 months after the intervention and total resolution of the ascites was observed.

  14. Footing the bill: patient portals, part I.

    PubMed

    Lawrence, Daphne

    2009-05-01

    Tie financial portal strategy into overall portal strategy. Savings from patient portals for finance come in the areas of call center volumes, bill pay, scheduling, and increased volume. Financial functions on the patient portal should be balanced with clinical functions. Improve the revenue cycle process before going to a portal.

  15. Imaging diagnosis of portal hypertension.

    PubMed

    Conangla-Planes, M; Serres, X; Persiva, O; Augustín, S

    2018-02-19

    Portal hypertension is a clinical entity defined by a hydrostatic pressure greater than 5mm Hg in the portal territory, being clinically significant when it is greater than or equal to 10mm Hg. Starting from this threshold, complications can develop, such as the bleeding of esophageal varices, the appearance of ascites, or hepatic encephalopathy. Imaging techniques play an important role as a noninvasive method for determining whether portal hypertension is present. This article analyzes various imaging findings that can suggest the presence of portal hypertension and can help to define its etiology, severity, and possible complications. Copyright © 2018. Publicado por Elsevier España, S.L.U.

  16. A systematic review of studies of web portals for patients with diabetes mellitus

    PubMed Central

    Williams, Lovoria B.; Hatzigeorgiou, Christos

    2017-01-01

    Patient web portals are password-protected online websites that offer patients 24-hour access to personal health information from anywhere with an Internet connection. Due to advances in health information technologies, there has been increasing interest among providers and researchers in patient web portals for use by patients with diabetes and other chronic conditions. This article, which is based upon bibliographic searches in PubMed, reviews web portals for patients with diabetes mellitus including patient web portals tethered to electronic medical records and web portals developed specifically for patients with diabetes. Twelve studies of the impact of patient web portals on the management of diabetes patients were identified. Three had a cross-sectional design, 1 employed mixed-methods, one had a matched-control design, 3 had a retrospective cohort design, and 5 were randomized controlled trials. Six (50%) of the studies examined web portals tethered to electronic medical records and the remainder were web portals developed specifically for diabetes patients. The results of this review suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control. However, results from observational studies indicate that many diabetic patients do not take advantage of web portal features such as secure messaging, perhaps because of a lack of internet access or lack of experience in navigating web portal resources. Although results from randomized controlled trials provide stronger evidence of the efficacy of web portal use in improving glycemic control among diabetic patients, the number of trials is small and results from the trials have been mixed. Studies suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control, but negative findings have also been reported. The number of randomized controlled trials that have examined the efficacy of web

  17. A systematic review of studies of web portals for patients with diabetes mellitus.

    PubMed

    Coughlin, Steven S; Williams, Lovoria B; Hatzigeorgiou, Christos

    2017-01-01

    Patient web portals are password-protected online websites that offer patients 24-hour access to personal health information from anywhere with an Internet connection. Due to advances in health information technologies, there has been increasing interest among providers and researchers in patient web portals for use by patients with diabetes and other chronic conditions. This article, which is based upon bibliographic searches in PubMed, reviews web portals for patients with diabetes mellitus including patient web portals tethered to electronic medical records and web portals developed specifically for patients with diabetes. Twelve studies of the impact of patient web portals on the management of diabetes patients were identified. Three had a cross-sectional design, 1 employed mixed-methods, one had a matched-control design, 3 had a retrospective cohort design, and 5 were randomized controlled trials. Six (50%) of the studies examined web portals tethered to electronic medical records and the remainder were web portals developed specifically for diabetes patients. The results of this review suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control. However, results from observational studies indicate that many diabetic patients do not take advantage of web portal features such as secure messaging, perhaps because of a lack of internet access or lack of experience in navigating web portal resources. Although results from randomized controlled trials provide stronger evidence of the efficacy of web portal use in improving glycemic control among diabetic patients, the number of trials is small and results from the trials have been mixed. Studies suggest that secure messaging between adult diabetic patients and their clinician is associated with improved glycemic control, but negative findings have also been reported. The number of randomized controlled trials that have examined the efficacy of web

  18. aSi EPIDs for the in-vivo dosimetry of static and dynamic beams

    NASA Astrophysics Data System (ADS)

    Piermattei, A.; Cilla, S.; Azario, L.; Greco, F.; Russo, M.; Grusio, M.; Orlandini, L.; Fidanzio, A.

    2015-10-01

    Portal imaging by amorphous silicon (aSi) photodiode is currently the most applied technology for in-vivo dosimetry (IVD) of static and dynamic radiotherapy beams. The strategy, adopted in this work to perform the IVD procedure by aSi EPID, is based on: in patient reconstruction of the isocenter dose and day to day comparison between 2D-portal images to verify the reproducibility of treatment delivery. About 20.000 tests have been carried out in this last 3 years in 8 radiotherapy centers using the SOFTDISO program. The IVD results show that: (i) the procedure can be implemented for linacs of different manufacturer, (ii) the IVD analysis can be obtained on a computer screen, in quasi real time (about 2 min after the treatment delivery) and (iii) once the causes of the discrepancies were eliminated, all the global IVD tests for single patient were within the acceptance criteria defined by: ±5% for the isocenter dose, and Pγ<1≥90% of the checked points for the 2D portal image γ-analysis. This work is the result of a project supported by the Istituto Nazionale di Fisica Nucleare (INFN) and Università Cattolica del S.Cuore (UCSC).

  19. Building Portals for Higher Education.

    ERIC Educational Resources Information Center

    Pickett, Richard A.; Hamre, William B.

    2002-01-01

    Presents the elements, components, and processes involved in setting and maintaining Web portals. Uses Santa Barbara City College as a case study of a portal implementation with the purpose of supporting knowledge management; underscores the role played and benefits gained by institutional research and the college as a result. (EV)

  20. Of Portals, Policies, and Poets

    ERIC Educational Resources Information Center

    Bunt, Rick; Pennock, Lea

    2006-01-01

    Universities are drawn to portals as an effective way of organizing and delivering campus services and information. In a university environment, where the desire for local autonomy and the impetus for centralization are in constant tension, a portal seems especially appealing because it allows local solutions through a shared medium. But the fact…

  1. All Roads Lead to Portal

    ERIC Educational Resources Information Center

    Heid, Susan D.

    2007-01-01

    Portals are taking off on campuses nationwide. According to "Campus Computing 2006," the Campus Computing Project's survey of 540 two- and four-year public and private colleges and universities across the US, portal deployment for four-year public residential universities jumped from 28 to 74 percent of responding institutions between the…

  2. The Power in the Portal

    ERIC Educational Resources Information Center

    Chamberlain, Cathy

    2005-01-01

    Educational portals put together links to sites and resources educators would be interested in viewing. They eliminate the hours of searching that might be invested if typical search engines were used. Educational portals feature lessons, units, printable resources, creative ideas, and more. Many of these sites are free, while others are…

  3. Lunar and Vesta Web Portals

    NASA Astrophysics Data System (ADS)

    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. 3. East portal of Tunnel 34, view to southsouthwest, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. East portal of Tunnel 34, view to south-southwest, 135mm lens with electronic flash fill. Note the shift, in these later tunnels east of Colfax, to concrete portal faces with granite masonry voussoirs and coping. - Central Pacific Transcontinental Railroad, Tunnel No. 34, Milepost 145.4, Colfax, Placer County, CA

  5. Factors Affecting the Use of an E-Learning Portal at University

    ERIC Educational Resources Information Center

    Cegarra-Navarro, Juan-Gabriel; Rodriguez, Francisco Javier Canovas

    2012-01-01

    Electronic learning (e-learning) portals can be defined as websites that store and present materials for online learning, training, performance assessment, and certification. Few, if any, studies have investigated the factors that might contribute to the integration or implementation of e-learning portals in universities. With the development of…

  6. The Portuguese Climate Portal

    NASA Astrophysics Data System (ADS)

    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

  7. Transit dosimetry in IMRT with an a-Si EPID in direct detection configuration

    NASA Astrophysics Data System (ADS)

    Sabet, Mahsheed; Rowshanfarzad, Pejman; Vial, Philip; Menk, Frederick W.; Greer, Peter B.

    2012-08-01

    In this study an amorphous silicon electronic portal imaging device (a-Si EPID) converted to direct detection configuration was investigated as a transit dosimeter for intensity modulated radiation therapy (IMRT). After calibration to dose and correction for a background offset signal, the EPID-measured absolute IMRT transit doses for 29 fields were compared to a MatriXX two-dimensional array of ionization chambers (as reference) using Gamma evaluation (3%, 3 mm). The MatriXX was first evaluated as reference for transit dosimetry. The accuracy of EPID measurements was also investigated by comparison of point dose measurements by an ionization chamber on the central axis with slab and anthropomorphic phantoms in a range of simple to complex fields. The uncertainty in ionization chamber measurements in IMRT fields was also investigated by its displacement from the central axis and comparison with the central axis measurements. Comparison of the absolute doses measured by the EPID and MatriXX with slab phantoms in IMRT fields showed that on average 96.4% and 97.5% of points had a Gamma index<1 in head and neck and prostate fields, respectively. For absolute dose comparisons with anthropomorphic phantoms, the values changed to an average of 93.6%, 93.7% and 94.4% of points with Gamma index<1 in head and neck, brain and prostate fields, respectively. Point doses measured by the EPID and ionization chamber were within 3% difference for all conditions. The deviations introduced in the response of the ionization chamber in IMRT fields were<1%. The direct EPID performance for transit dosimetry showed that it has the potential to perform accurate, efficient and comprehensive in vivo dosimetry for IMRT.

  8. The Higgs Portal and Cosmology

    SciTech Connect

    Assamagan, Ketevi; Chien-Yi Chen; Chou, John Paul

    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.

  9. 29 CFR 785.34 - Effect of section 4 of the Portal-to-Portal Act.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 3 2014-07-01 2014-07-01 false Effect of section 4 of the Portal-to-Portal Act. 785.34... of Principles Traveltime § 785.34 Effect of section 4 of the Portal-to-Portal Act. The Portal Act... employee and activities that are incidental to the use of such vehicle for commuting are not considered...

  10. 29 CFR 785.34 - Effect of section 4 of the Portal-to-Portal Act.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 3 2011-07-01 2011-07-01 false Effect of section 4 of the Portal-to-Portal Act. 785.34... of Principles Traveltime § 785.34 Effect of section 4 of the Portal-to-Portal Act. The Portal Act... employee and activities that are incidental to the use of such vehicle for commuting are not considered...

  11. 29 CFR 785.34 - Effect of section 4 of the Portal-to-Portal Act.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 3 2013-07-01 2013-07-01 false Effect of section 4 of the Portal-to-Portal Act. 785.34... of Principles Traveltime § 785.34 Effect of section 4 of the Portal-to-Portal Act. The Portal Act... employee and activities that are incidental to the use of such vehicle for commuting are not considered...

  12. 29 CFR 785.34 - Effect of section 4 of the Portal-to-Portal Act.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 3 2012-07-01 2012-07-01 false Effect of section 4 of the Portal-to-Portal Act. 785.34... of Principles Traveltime § 785.34 Effect of section 4 of the Portal-to-Portal Act. The Portal Act... employee and activities that are incidental to the use of such vehicle for commuting are not considered...

  13. The Electronic Patient Reported Outcome Tool: Testing Usability and Feasibility of a Mobile App and Portal to Support Care for Patients With Complex Chronic Disease and Disability in Primary Care Settings

    PubMed Central

    Gill, Ashlinder; Khan, Anum Irfan; Hans, Parminder Kaur; Kuluski, Kerry; Cott, Cheryl

    2016-01-01

    Background People experiencing complex chronic disease and disability (CCDD) face some of the greatest challenges of any patient population. Primary care providers find it difficult to manage multiple discordant conditions and symptoms and often complex social challenges experienced by these patients. The electronic Patient Reported Outcome (ePRO) tool is designed to overcome some of these challenges by supporting goal-oriented primary care delivery. Using the tool, patients and providers collaboratively develop health care goals on a portal linked to a mobile device to help patients and providers track progress between visits. Objectives This study tested the usability and feasibility of adopting the ePRO tool into a single interdisciplinary primary health care practice in Toronto, Canada. The Fit between Individuals, Fask, and Technology (FITT) framework was used to guide our assessment and explore whether the ePRO tool is: (1) feasible for adoption in interdisciplinary primary health care practices and (2) usable from both the patient and provider perspectives. This usability pilot is part of a broader user-centered design development strategy. Methods A 4-week pilot study was conducted in which patients and providers used the ePRO tool to develop health-related goals, which patients then monitored using a mobile device. Patients and providers collaboratively set goals using the system during an initial visit and had at least 1 follow-up visit at the end of the pilot to discuss progress. Focus groups and interviews were conducted with patients and providers to capture usability and feasibility measures. Data from the ePRO system were extracted to provide information regarding tool usage. Results Six providers and 11 patients participated in the study; 3 patients dropped out mainly owing to health issues. The remaining 8 patients completed 210 monitoring protocols, equal to over 1300 questions, with patients often answering questions daily. Providers and patients

  14. Local Government Solar Project Portal

    EPA Pesticide Factsheets

    The Local Government Solar Project Portal provides step-by-step guidance and resources to assist local governments in solar project development, including case studies, fact sheets, presentations, templates, and more.

  15. Portal vein aneurysm in thalassaemia.

    PubMed

    Das, Simi; Dey, Mousam; Kumar, Vinay; Lal, Hira

    2017-08-11

    Arterial aneurysms are more common than visceral venous aneurysms. Portal vein aneurysms being the most common type of visceral venous aneurysms. Here, we present an 18-year-old young woman with thalassaemia major, who presented with headache, palpitation, shortness of breath and a recent increase in blood transfusion rate. On clinical examination, she had hepatosplenomegaly. Ultrasonography revealed hepatosplenomegaly with fusiform dilatation of extrahepatic portal vein, which was confirmed to be portal vein aneurysm on contrast enhanced CT. Though portal vein aneurysms were previously thought to be rare, recently they are increasingly diagnosed with the use of cross-sectional imaging. Recognition of this finding can help to avoid potential confusion with other periportal cystic masses of different aetiologies, especially on sonography. © BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  16. Gaiaverse: the Gaia's outreach portal

    NASA Astrophysics Data System (ADS)

    Masana, E.

    2017-03-01

    Gaiaverse (http://gaiaverse.eu) is a dissemination portal on the ESA Gaia's mission developed within the GENIUS project, an European project funded by the European Commission to boost the impact of the next European breakthrough in astrophysics, the Gaia astrometric mission. The portal was opened in July 2015. Gaiaverse is administrated by the Universitat de Barcelona (UB) and the Consorci de Serveis Universitaris de Catalunya (CSUC).

  17. 4. East portal of Tunnel 22, view to the eastsoutheast, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. East portal of Tunnel 22, view to the east-southeast, 135mm lens with electronic flash fill. Note the depth of water within the tunnel, a sympton of the spring-laden slope above the tunnel that led to its eventual abandonment. - Southern Pacific Railroad Natron Cutoff, Tunnel 23, Milepost 584.5, Westfir, Lane County, OR

  18. 1. West portal of Tunnel 34, contextual view to northeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West portal of Tunnel 34, contextual view to northeast from inside east end of Tunnel 33 (Cape Horn Tunnel), 135mm lens with electronic flash fill. - Central Pacific Transcontinental Railroad, Tunnel No. 34, Milepost 145.4, Colfax, Placer County, CA

  19. Racial/ethnic variation in devices used to access patient portals.

    PubMed

    Chang, Eva; Blondon, Katherine; Lyles, Courtney R; Jordan, Luesa; Ralston, James D

    2018-01-01

    We examined racial/ethnic variation in the devices used by patients to access medical records through an online patient portal. Retrospective, cross-sectional analysis. Using data from 318,700 adults enrolled in an integrated delivery system between December 2012 and November 2013, we examined: 1) online patient portal use that directly engages the electronic health record and 2) portal use over desktops/laptops only, mobile devices only, or both device types. The primary covariate was race/ethnicity (non-Hispanic white, black, Hispanic, and Asian). Other covariates included age, sex, primary language, and neighborhood-level income and education. Portal use and devices used were assessed with multiple and multinomial logistic models, respectively. From December 2012 to November 2013, 56% of enrollees used the patient portal. Of these portal users, 62% used desktops/laptops only, 6% used mobile devices only, and 32% used both desktops/laptops and mobile devices. Black, Hispanic, and Asian enrollees had significantly lower odds of portal use than whites. Black and Hispanic portal users also were significantly more likely to use mobile devices only (relative risk ratio, 1.73 and 1.44, respectively) and both device types (1.21 and 1.07, respectively) than desktops/laptops only compared with whites. Although racial/ethnic minority enrollees were less likely to access the online patient portal overall, a greater proportion of black and Hispanic users accessed the patient portal with mobile devices than did non-Hispanic white users. The rapid spread of mobile devices among racial/ethnic minorities may help reduce variation in online patient portal use. Mobile device use may represent an opportunity for healthcare organizations to further engage black and Hispanic enrollees in online patient portal use.

  20. Density-functional theory molecular dynamics simulations of a-HfO2/a-SiO2/SiGe and a-HfO2/a-SiO2/Ge with a-SiO2 and a-SiO suboxide interfacial layers

    NASA Astrophysics Data System (ADS)

    Chagarov, Evgueni A.; Kavrik, Mahmut S.; Fang, Ziwei; Tsai, Wilman; Kummel, Andrew C.

    2018-06-01

    Comprehensive Density-Functional Theory (DFT) Molecular Dynamics (MD) simulations were performed to investigate interfaces between a-HfO2 and SiGe or Ge semiconductors with fully-stoichiometric a-SiO2 or sub-oxide SiO interlayers. The electronic structure of the selected stacks was calculated with a HSE06 hybrid functional. Simulations were performed before and after hydrogen passivation of residual interlayer defects. For the SiGe substrate with Ge termination prior to H passivation, the stacks with a-SiO suboxide interlayer (a-HfO2/a-SiO/SiGe) demonstrate superior electronic properties and wider band-gaps than the stacks with fully coordinated a-SiO2 interlayers (a-HfO2/a-SiO2/SiGe). After H passivation, most of the a-HfO2/a-SiO2/SiGe defects are passivated. To investigate effect of random placement of Si and Ge atoms additional simulations with a randomized SiGe slab were performed demonstrating improvement of electronic structure. For Ge substrates, before H passivation, the stacks with a SiO suboxide interlayer (a-HfO2/a-SiO/Ge) also demonstrate wider band-gaps than the stacks with fully coordinated a-SiO2 interlayers (a-HfO2/a-SiO2/Ge). However, even for a-HfO2/a-SiO/Ge, the Fermi level is shifted close to the conduction band edge (CBM) consistent with Fermi level pinning. Again, after H passivation, most of the a-HfO2/a-SiO2/Ge defects are passivated. The stacks with fully coordinated a-SiO2 interlayers have much stronger deformation and irregularity in the semiconductor (SiGe or Ge) upper layers leading to multiple under-coordinated atoms which create band-edge states and decrease the band-gap prior to H passivation.

  1. Earthdata Developer Portal poster

    NASA Astrophysics Data System (ADS)

    Plofchan, P.

    2016-12-01

    A common theme at community conferences in the Earth science domain is the need for more integration with related services, clearer documentation for services available, and a general simplification of what it takes to leverage existing tools so that setup and administration time can be minimized and time spent researching can be maximized. NASA's Earthdata Developer Portal (EDP) is the newly-created central location for documentation related to interacting with services offered by the EOSDIS community. The EDP will provide technical documentation for APIs, process documentation that provides real-world examples of how to use existing APIs in the real world, release notes for applications and services so that the entire community can stay up to date on recent updates, and best practice suggestions to improve implementation of both front-end and back-end services. Application and service owners will own their documentation while the EDP will ingest the documentation, serve it up in an interface using both industry standard tools, such as Swagger, and custom "adapters". The content is then styled to ensure consistency with other documentation found throughout the site and will be made searchable from a single location. "Getting Started" paths will also provide those users new to the space a simple path to follow to perform common tasks such as "searching and getting data" or "hosting an application on the Earthdata platform."

  2. Idiopathic portal hypertension and extrahepatic portal venous obstruction.

    PubMed

    Khanna, Rajeev; Sarin, Shiv Kumar

    2018-02-01

    Idiopathic portal hypertension (IPH) and extrahepatic portal venous obstruction (EHPVO) are non-cirrhotic vascular causes of portal hypertension (PHT). Variceal bleed and splenomegaly are the commonest presentations. The present review is intended to provide the existing literature on etiopathogenesis, clinical profile, diagnosis, natural history and management of IPH and EHPVO. IPH and EHPVO are both characterized by normal hepatic venous pressure gradient, moderate to massive splenomegaly with preserved liver synthetic functions. While the level of block in IPH is presinusoidal, in EHPVO it is at prehepatic level. Infections, autoimmunity, drugs, immunodeficiency and prothrombotic states are possible etiological agents in IPH. Contrastingly in EHPVO, prothrombotic disorders and local factors around the portal vein are the incriminating factors. Diagnosis is often clinical, supported by simple radiological tools. Natural history is defined by episodes of variceal bleed and symptoms related to enlarged spleen. Growth failure, portal biliopathy and minimal hepatic encephalopathy are additional concerns in EHPVO. Long-term survival is reasonably good with endoscopic surveillance; however, parenchymal extinction leading to decompensation is seen in a minority of patients in both the disorders. Surgical shunts revert the complications secondary to PHT. Meso-Rex shunt has become the standard surgery in children with EHPVO. This review gives a detailed summary of these two vascular conditions of liver-IPH and EHPVO. Further research is needed to understand the pathogenesis and natural history of these disorders.

  3. Clinical Implementation of a Model-Based In Vivo Dose Verification System for Stereotactic Body Radiation Therapy–Volumetric Modulated Arc Therapy Treatments Using the Electronic Portal Imaging Device

    SciTech Connect

    McCowan, Peter M., E-mail: pmccowan@cancercare.mb.ca; Asuni, Ganiyu; Van Uytven, Eric

    Purpose: To report findings from an in vivo dosimetry program implemented for all stereotactic body radiation therapy patients over a 31-month period and discuss the value and challenges of utilizing in vivo electronic portal imaging device (EPID) dosimetry clinically. Methods and Materials: From December 2013 to July 2016, 117 stereotactic body radiation therapy–volumetric modulated arc therapy patients (100 lung, 15 spine, and 2 liver) underwent 602 EPID-based in vivo dose verification events. A developed model-based dose reconstruction algorithm calculates the 3-dimensional dose distribution to the patient by back-projecting the primary fluence measured by the EPID during treatment. The EPID frame-averaging was optimized in Junemore » 2015. For each treatment, a 3%/3-mm γ comparison between our EPID-derived dose and the Eclipse AcurosXB–predicted dose to the planning target volume (PTV) and the ≥20% isodose volume were performed. Alert levels were defined as γ pass rates <85% (lung and liver) and <80% (spine). Investigations were carried out for all fractions exceeding the alert level and were classified as follows: EPID-related, algorithmic, patient setup, anatomic change, or unknown/unidentified errors. Results: The percentages of fractions exceeding the alert levels were 22.6% for lung before frame-average optimization and 8.0% for lung, 20.0% for spine, and 10.0% for liver after frame-average optimization. Overall, mean (± standard deviation) planning target volume γ pass rates were 90.7% ± 9.2%, 87.0% ± 9.3%, and 91.2% ± 3.4% for the lung, spine, and liver patients, respectively. Conclusions: Results from the clinical implementation of our model-based in vivo dose verification method using on-treatment EPID images is reported. The method is demonstrated to be valuable for routine clinical use for verifying delivered dose as well as for detecting errors.« less

  4. Clinical Implementation of a Model-Based In Vivo Dose Verification System for Stereotactic Body Radiation Therapy-Volumetric Modulated Arc Therapy Treatments Using the Electronic Portal Imaging Device.

    PubMed

    McCowan, Peter M; Asuni, Ganiyu; Van Uytven, Eric; VanBeek, Timothy; McCurdy, Boyd M C; Loewen, Shaun K; Ahmed, Naseer; Bashir, Bashir; Butler, James B; Chowdhury, Amitava; Dubey, Arbind; Leylek, Ahmet; Nashed, Maged

    2017-04-01

    To report findings from an in vivo dosimetry program implemented for all stereotactic body radiation therapy patients over a 31-month period and discuss the value and challenges of utilizing in vivo electronic portal imaging device (EPID) dosimetry clinically. From December 2013 to July 2016, 117 stereotactic body radiation therapy-volumetric modulated arc therapy patients (100 lung, 15 spine, and 2 liver) underwent 602 EPID-based in vivo dose verification events. A developed model-based dose reconstruction algorithm calculates the 3-dimensional dose distribution to the patient by back-projecting the primary fluence measured by the EPID during treatment. The EPID frame-averaging was optimized in June 2015. For each treatment, a 3%/3-mm γ comparison between our EPID-derived dose and the Eclipse AcurosXB-predicted dose to the planning target volume (PTV) and the ≥20% isodose volume were performed. Alert levels were defined as γ pass rates <85% (lung and liver) and <80% (spine). Investigations were carried out for all fractions exceeding the alert level and were classified as follows: EPID-related, algorithmic, patient setup, anatomic change, or unknown/unidentified errors. The percentages of fractions exceeding the alert levels were 22.6% for lung before frame-average optimization and 8.0% for lung, 20.0% for spine, and 10.0% for liver after frame-average optimization. Overall, mean (± standard deviation) planning target volume γ pass rates were 90.7% ± 9.2%, 87.0% ± 9.3%, and 91.2% ± 3.4% for the lung, spine, and liver patients, respectively. Results from the clinical implementation of our model-based in vivo dose verification method using on-treatment EPID images is reported. The method is demonstrated to be valuable for routine clinical use for verifying delivered dose as well as for detecting errors. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. On flattening filter‐free portal dosimetry

    PubMed Central

    Novais, Juan Castro; Molina López, María Yolanda; Maqueda, Sheila Ruiz

    2016-01-01

    Varian introduced (in 2010) the option of removing the flattening filter (FF) in their C‐Arm linacs for intensity‐modulated treatments. This mode, called flattening filter‐free (FFF), offers the advantage of a greater dose rate. Varian's “Portal Dosimetry” is an electronic portal imager device (EPID)‐based tool for IMRT verification. This tool lacks the capability of verifying flattening filter‐free (FFF) modes due to saturation and lack of an image prediction algorithm. (Note: the latest versions of this software and EPID correct these issues.) The objective of the present study is to research the feasibility of said verifications (with the older versions of the software and EPID). By placing the EPID at a greater distance, the images can be acquired without saturation, yielding a linearity similar to the flattened mode. For the image prediction, a method was optimized based on the clinically used algorithm (analytical anisotropic algorithm (AAA)) over a homogeneous phantom. The depth inside the phantom and its electronic density were tailored. An application was developed to allow the conversion of a dose plane (in DICOM format) to Varian's custom format for Portal Dosimetry. The proposed method was used for the verification of test and clinical fields for the three qualities used in our institution for IMRT: 6X, 6FFF and 10FFF. The method developed yielded a positive verification (more than 95% of the points pass a 2%/2 mm gamma) for both the clinical and test fields. This method was also capable of “predicting” static and wedged fields. A workflow for the verification of FFF fields was developed. This method relies on the clinical algorithm used for dose calculation and is able to verify the FFF modes, as well as being useful for machine quality assurance. The procedure described does not require new hardware. This method could be used as a verification of Varian's Portal Dose Image Prediction. PACS number(s): 87.53.Kn, 87.55.T‐, 87.56.bd

  6. Meaningful Use and the Patient Portal: Patient enrollment, use and satisfaction with patient portals at a later-adopting center

    PubMed Central

    Neuner, Joan; Fedders, Megan; Caravella, Mary; Bradford, Lisa; Schapira, Marilyn

    2014-01-01

    Many physicians are adopting patient portals in response to governmental incentives for meaningful use (MU), but the stage 2 requirements for portal use may be particularly challenging for newer electronic health record (EHR) users. This study examined enrollment, use based on MU requirements, and satisfaction in a recently adopting fee-for-service multispecialty system. Between 2010–2012, overall portal enrollment increased from 13.2% to 23.1% but varied substantially by physician specialty. In 2013, over 97% of physicians would have met requirements for a stage 2 MU utilization measure requiring that patients download personal health information, but only 38% of all physicians (87% of primary care physicians [PCPs] and 37% of other specialists) would have met e-mail requirements. Satisfaction with the portal overall and with portal-based e-mails was high. These results suggest that later-adopting PCPs can succeed in providing satisfactory record and e-mail access but specialists may find reaching e-mail thresholds more difficult. PMID:24563085

  7. Reliability in endoscopic diagnosis of portal hypertensive gastropathy

    PubMed Central

    de Macedo, George Fred Soares; Ferreira, Fabio Gonçalves; Ribeiro, Maurício Alves; Szutan, Luiz Arnaldo; Assef, Mauricio Saab; Rossini, Lucio Giovanni Battista

    2013-01-01

    AIM: To analyze reliability among endoscopists in diagnosing portal hypertensive gastropathy (PHG) and to determine which criteria from the most utilized classifications are the most suitable. METHODS: From January to July 2009, in an academic quaternary referral center at Santa Casa of São Paulo Endoscopy Service, Brazil, we performed this single-center prospective study. In this period, we included 100 patients, including 50 sequential patients who had portal hypertension of various etiologies; who were previously diagnosed based on clinical, laboratory and imaging exams; and who presented with esophageal varices. In addition, our study included 50 sequential patients who had dyspeptic symptoms and were referred for upper digestive endoscopy without portal hypertension. All subjects underwent upper digestive endoscopy, and the images of the exam were digitally recorded. Five endoscopists with more than 15 years of experience answered an electronic questionnaire, which included endoscopic criteria from the 3 most commonly used Portal Hypertensive Gastropathy classifications (McCormack, NIEC and Baveno) and the presence of elevated or flat antral erosive gastritis. All five endoscopists were blinded to the patients’ clinical information, and all images of varices were deliberately excluded for the analysis. RESULTS: The three most common etiologies of portal hypertension were schistosomiasis (36%), alcoholic cirrhosis (20%) and viral cirrhosis (14%). Of the 50 patients with portal hypertension, 84% were Child A, 12% were Child B, 4% were Child C, 64% exhibited previous variceal bleeding and 66% were previously endoscopic treated. The endoscopic parameters, presence or absence of mosaic-like pattern, red point lesions and cherry-red spots were associated with high inter-observer reliability and high specificity for diagnosing Portal Hypertensive Gastropathy. Sensitivity, specificity and reliability for the diagnosis of PHG (%) were as follows: mosaic-like pattern

  8. From EGEE Operations Portal towards EGI Operations Portal

    NASA Astrophysics Data System (ADS)

    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.

  9. VisEL: Visualisation of Expertise Level in a Special Interest Group Knowledge Portal

    NASA Astrophysics Data System (ADS)

    Zulhafizsyam Wan Ahmad, Wan Muhammad; Sulaiman, Shahida; Yusof, Umi Kalsom

    A variety of portals are available nowadays to support diverse purposes such as commercial, publishing, personal, affinity and corporate portals. Affinity portals promote electronic communities who share common interest such as a special interest group (SIG). Knowledge portal is an emerging trend that benefits the existing portal technology by designing such portals with proper representation of the members' shared knowledge. Besides textual representation for diverse expertise levels, graphical visualisation will be able to support the requirements in searching and representing expertise level among e-community. There is a number of existing SIG portals available. However, they do not visualise effectively and accurately the expertise level of members and make it difficult for users to search their targeted experts for instance searching the highest expertise level to have a discussion and to solve their problems related to a project. The goal of this paper is to propose a graphical visualisation of expertise level method (VisEL) using an interactive tag cloud technique that represents expertise level of each member based on their knowledge in a software engineering SIG portal.

  10. Software tool for portal dosimetry research.

    PubMed

    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.

  11. Is light-induced degradation of a-Si:H/c-Si interfaces reversible?

    SciTech Connect

    El Mhamdi, El Mahdi; Holovsky, Jakub; Demaurex, Bénédicte

    2014-06-23

    Thin hydrogenated amorphous silicon (a-Si:H) films deposited on crystalline silicon (c-Si) surfaces are sensitive probes for the bulk electronic properties of a-Si:H. Here, we use such samples during repeated low-temperature annealing and visible-light soaking to investigate the long-term stability of a-Si:H films. We observe that during annealing the electronic improvement of the interfaces follows stretched exponentials as long as hydrogen evolution in the films can be detected. Once such evolution is no longer observed, the electronic improvement occurs much faster. Based on these findings, we discuss how the reversibility of light-induced defects depends on (the lack of observable) hydrogen evolution.

  12. A multiresolution processing method for contrast enhancement in portal imaging.

    PubMed

    Gonzalez-Lopez, Antonio

    2018-06-18

    Portal images have a unique feature among the imaging modalities used in radiotherapy: they provide direct visualization of the irradiated volumes. However, contrast and spatial resolution are strongly limited due to the high energy of the radiation sources. Because of this, imaging modalities using x-ray energy beams have gained importance in the verification of patient positioning, replacing portal imaging. The purpose of this work was to develop a method for the enhancement of local contrast in portal images. The method operates in the subbands of a wavelet decomposition of the image, re-scaling them in such a way that coefficients in the high and medium resolution subbands are amplified, an approach totally different of those operating on the image histogram, widely used nowadays. Portal images of an anthropomorphic phantom were acquired in an electronic portal imaging device (EPID). Then, different re-scaling strategies were investigated, studying the effects of the scaling parameters on the enhanced images. Also, the effect of using different types of transforms was studied. Finally, the implemented methods were combined with histogram equalization methods like the contrast limited adaptive histogram equalization (CLAHE), and these combinations were compared. Uniform amplification of the detail subbands shows the best results in contrast enhancement. On the other hand, linear re-escalation of the high resolution subbands increases the visibility of fine detail of the images, at the expense of an increase in noise levels. Also, since processing is applied only to detail subbands, not to the approximation, the mean gray level of the image is minimally modified and no further display adjustments are required. It is shown that re-escalation of the detail subbands of portal images can be used as an efficient method for the enhancement of both, the local contrast and the resolution of these images. © 2018 Institute of

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

    PubMed

    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.

  14. Structural properties of a-Si films and their effect on aluminum induced crystallization

    SciTech Connect

    Tankut, Aydin; Ozkol, Engin; Karaman, Mehmet

    2015-10-15

    In this paper, we report the influence of the structural properties of amorphous silicon (a-Si) on its subsequent crystallization behavior via the aluminum induced crystallization (AIC) method. Two distinct a-Si deposition techniques, electron beam evaporation and plasma enhanced chemical vapor deposition (PECVD), are compared for their effect on the overall AIC kinetics as well as the properties of the final poly-crystalline (poly-Si) silicon film. Raman and FTIR spectroscopy results indicate that the PECVD grown a-Si films has higher intermediate-range order, which is enhanced for increased hydrogen dilution during deposition. With increasing intermediate-range order of the a-Si, the rate of AICmore » is diminished, leading larger poly-Si grain size.« less

  15. The ARL Scholars Portal Initiative.

    ERIC Educational Resources Information Center

    Jackson, Mary E.

    2002-01-01

    Describes an initiative of the Association of Research Libraries (ARL), the Scholars Portal Initiative, a three-year collaborative effort which seeks to provide tools for an academic community to have a single point of access on the Web to find high-quality information resources and to deliver the information and related services directly to the…

  16. RECOMBINATION PROCESSES AND NATURE OF THE TAIL AND GAP STATES IN a-Si:H and a-Si:H/a-SiNx:H MULTILAYERS

    NASA Astrophysics Data System (ADS)

    Morigaki, K.

    We discuss recombination processes and nature of the tail and gap states in a-Si:H and a-Si:H/a-SiNx:H multilayers on the basis of our ODMR, luminescence, photoinduced absorption and ENDOR measurements. We present other results relevant to this subject and attempt to interpret them in terms of our model.

  17. The new IAGOS Database Portal

    NASA Astrophysics Data System (ADS)

    Boulanger, Damien; Gautron, Benoit; Thouret, Valérie; Fontaine, Alain

    2016-04-01

    IAGOS (In-service Aircraft for a Global Observing System) is a European Research Infrastructure which aims at the provision of long-term, regular and spatially resolved in situ observations of the atmospheric composition. IAGOS observation systems are deployed on a fleet of commercial aircraft. The IAGOS database is an essential part of the global atmospheric monitoring network. It contains IAGOS-core data and IAGOS-CARIBIC (Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container) data. The IAGOS Database Portal (http://www.iagos.fr, damien.boulanger@obs-mip.fr) is part of the French atmospheric chemistry data center AERIS (http://www.aeris-data.fr). The new IAGOS Database Portal has been released in December 2015. The main improvement is the interoperability implementation with international portals or other databases in order to improve IAGOS data discovery. In the frame of the IGAS project (IAGOS for the Copernicus Atmospheric Service), a data network has been setup. It is composed of three data centers: the IAGOS database in Toulouse; the HALO research aircraft database at DLR (https://halo-db.pa.op.dlr.de); and the CAMS data center in Jülich (http://join.iek.fz-juelich.de). The CAMS (Copernicus Atmospheric Monitoring Service) project is a prominent user of the IGAS data network. The new portal provides improved and new services such as the download in NetCDF or NASA Ames formats, plotting tools (maps, time series, vertical profiles, etc.) and user management. Added value products are available on the portal: back trajectories, origin of air masses, co-location with satellite data, etc. The link with the CAMS data center, through JOIN (Jülich OWS Interface), allows to combine model outputs with IAGOS data for inter-comparison. Finally IAGOS metadata has been standardized (ISO 19115) and now provides complete information about data traceability and quality.

  18. Portal vein thrombosis in paroxysmal nocturnal haemoglobinuria.

    PubMed

    Tomizuka, H; Hatake, K; Kitagawa, S; Yamashita, K; Arai, H; Miura, Y

    1999-01-01

    A 28-year-old man was hospitalized with nausea, vomiting, abdominal pain and low-grade fever. He had a 6-month history of paroxysmal nocturnal haemoglobinuria (PNH), and laboratory data showed anaemia and liver dysfunction. An abdominal ultrasonography showed ascites and portal vein thrombosis. After receiving antithrombotic treatment, the portal vein thrombosis did not extend. Portal vein thrombosis is very rare but should be considered when we encounter liver dysfunction associated with PNH as well as hepatic vein thrombosis. Ultrasonography is very useful in detecting portal vein thrombosis and facilitating early diagnosis. Warfarin is very effective in preventing exacerbation of portal vein thrombosis in PNH.

  19. [Changes in the peritoneum of the small intestine and diaphragm in experimental portal hypertension].

    PubMed

    Khoroshaev, V A; Vorozheĭkin, V M; Baĭbekov, I M

    1991-04-01

    Diaphragm and small intestine peritoneum morphology was studied in experimental portal hypertension in rats with the help of luminescent, transmission and scanning electron microscopy techniques. Structural organizations of these peritoneum portions and performance function were different: fluid transudation realized through the small intestine peritoneum and resorption occurred via diaphragm peritoneum. Morphological signs allowed to judge about the increasing of fluid transudation in abdominal cavity and diaphragmatic resorption in early period of portal hypertension. Morphological alterations appeared in peritoneum resorption sites (pumping diaphragmatic hatchs) according to progress of portal hypertension that indicated decompensation process of peritoneal fluid absorption and led to ascites.

  20. H2O incorporation in the phosphorene/a-SiO2 interface: a first-principles study

    NASA Astrophysics Data System (ADS)

    Scopel, Wanderlã L.; Souza, Everson S.; Miwa, R. H.

    2017-02-01

    Based on first-principles calculations, we investigate (i) the energetic stability and electronic properties of single-layer phosphorene (SLP) adsorbed on an amorphous SiO2 surface (SLP/a-SiO2), and (ii) the further incorporation of water molecules at the phosphorene/a-SiO2 interface. In (i), we find that the phosphorene sheet binds to a-SiO2 through van der Waals interactions, even in the presence of oxygen vacancies on the surface. The SLP/a-SiO2 system presents a type-I band alignment, with the valence (conduction) band maximum (minimum) of the phosphorene lying within the energy gap of the a-SiO2 substrate. The structure and the surface-potential corrugations promote the formation of electron-rich and electron-poor regions on the phosphorene sheet and at the SLP/a-SiO2 interface. Such charge density puddles are strengthened by the presence of oxygen vacancies in a-SiO2. In (ii), because of the amorphous structure of the surface, we consider a number of plausible geometries for H2O embedded in the SLP/a-SiO2 interface. There is an energetic preference for the formation of hydroxyl (OH) groups on the a-SiO2 surface. Meanwhile, in the presence of oxygenated water or interstitial oxygen in the phosphorene sheet, we observe the formation of metastable OH bonded to the phosphorene, and the formation of energetically stable P-O-Si chemical bonds at the SLP/a-SiO2 interface. Further x-ray absorption spectra simulations are performed, which aim to provide additional structural/electronic information on the oxygen atoms forming hydroxyl groups or P-O-Si chemical bonds at the interface region.

  1. H2O incorporation in the phosphorene/a-SiO2 interface: a first-principles study.

    PubMed

    Scopel, Wanderlã L; Souza, Everson S; Miwa, R H

    2017-02-22

    Based on first-principles calculations, we investigate (i) the energetic stability and electronic properties of single-layer phosphorene (SLP) adsorbed on an amorphous SiO 2 surface (SLP/a-SiO 2 ), and (ii) the further incorporation of water molecules at the phosphorene/a-SiO 2 interface. In (i), we find that the phosphorene sheet binds to a-SiO 2 through van der Waals interactions, even in the presence of oxygen vacancies on the surface. The SLP/a-SiO 2 system presents a type-I band alignment, with the valence (conduction) band maximum (minimum) of the phosphorene lying within the energy gap of the a-SiO 2 substrate. The structure and the surface-potential corrugations promote the formation of electron-rich and electron-poor regions on the phosphorene sheet and at the SLP/a-SiO 2 interface. Such charge density puddles are strengthened by the presence of oxygen vacancies in a-SiO 2 . In (ii), because of the amorphous structure of the surface, we consider a number of plausible geometries for H 2 O embedded in the SLP/a-SiO 2 interface. There is an energetic preference for the formation of hydroxyl (OH) groups on the a-SiO 2 surface. Meanwhile, in the presence of oxygenated water or interstitial oxygen in the phosphorene sheet, we observe the formation of metastable OH bonded to the phosphorene, and the formation of energetically stable P-O-Si chemical bonds at the SLP/a-SiO 2 interface. Further x-ray absorption spectra simulations are performed, which aim to provide additional structural/electronic information on the oxygen atoms forming hydroxyl groups or P-O-Si chemical bonds at the interface region.

  2. Teen use of a patient portal: a qualitative study of parent and teen attitudes.

    PubMed

    Bergman, David A; Brown, Nancy L; Wilson, Sandra

    2008-01-01

    We conducted a qualitative study of the attitudes of teens and parents toward the use of a patient portal. We conducted two teen and two parent focus groups, one teen electronic bulletin board, and one parent electronic bulletin board. Videotapes and transcripts from the groups were independently analyzed by two reviewers for significant themes, which were then validated by two other members of the research team. Twenty-eight teens and 23 parents participated in the groups. Significant themes included issues about teens' control of their own healthcare; enthusiasm about the use of a patient portal to access their providers, seek health information, and make appointments; and concerns about confidentiality. In summary, there was considerable support among teens and parents for a patient portal as well as concerns about confidentiality. The teen portal affords an opportunity to negotiate issues of confidentiality.

  3. Developing Interoperable Air Quality Community Portals

    NASA Astrophysics Data System (ADS)

    Falke, S. R.; Husar, R. B.; Yang, C. P.; Robinson, E. M.; Fialkowski, W. E.

    2009-04-01

    Web portals are intended to provide consolidated discovery, filtering and aggregation of content from multiple, distributed web sources targeted at particular user communities. This paper presents a standards-based information architectural approach to developing portals aimed at air quality community collaboration in data access and analysis. An important characteristic of the approach is to advance beyond the present stand-alone design of most portals to achieve interoperability with other portals and information sources. We show how using metadata standards, web services, RSS feeds and other Web 2.0 technologies, such as Yahoo! Pipes and del.icio.us, helps increase interoperability among portals. The approach is illustrated within the context of the GEOSS Architecture Implementation Pilot where an air quality community portal is being developed to provide a user interface between the portals and clearinghouse of the GEOSS Common Infrastructure and the air quality community catalog of metadata and data services.

  4. Portal Connecting Dark Photons and Axions.

    PubMed

    Kaneta, Kunio; Lee, Hye-Sung; Yun, Seokhoon

    2017-03-10

    The dark photon and the axion (or axionlike particle) are popular light particles of the hidden sector. Each of them has been actively searched for through the couplings called the vector portal and the axion portal. We introduce a new portal connecting the dark photon and the axion (axion-photon-dark photon, axion-dark photon-dark photon), which emerges in the presence of the two particles. This dark axion portal is genuinely new couplings, not just from a product of the vector portal and the axion portal, because of the internal structure of these couplings. We present a simple model that realizes the dark axion portal and discuss why it warrants a rich phenomenology.

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

    PubMed

    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.

  6. Structure-function analysis of the DNA translocating portal of the bacteriophage T4 packaging machine.

    PubMed

    Padilla-Sanchez, Victor; Gao, Song; Kim, Hyung Rae; Kihara, Daisuke; Sun, Lei; Rossmann, Michael G; Rao, Venigalla B

    2014-03-06

    Tailed bacteriophages and herpesviruses consist of a structurally well conserved dodecameric portal at a special 5-fold vertex of the capsid. The portal plays critical roles in head assembly, genome packaging, neck/tail attachment, and genome ejection. Although the structures of portals from phages φ29, SPP1, and P22 have been determined, their mechanistic roles have not been well understood. Structural analysis of phage T4 portal (gp20) has been hampered because of its unusual interaction with the Escherichia coli inner membrane. Here, we predict atomic models for the T4 portal monomer and dodecamer, and we fit the dodecamer into the cryo-electron microscopy density of the phage portal vertex. The core structure, like that from other phages, is cone shaped with the wider end containing the "wing" and "crown" domains inside the phage head. A long "stem" encloses a central channel, and a narrow "stalk" protrudes outside the capsid. A biochemical approach was developed to analyze portal function by incorporating plasmid-expressed portal protein into phage heads and determining the effect of mutations on head assembly, DNA translocation, and virion production. We found that the protruding loops of the stalk domain are involved in assembling the DNA packaging motor. A loop that connects the stalk to the channel might be required for communication between the motor and the portal. The "tunnel" loops that project into the channel are essential for sealing the packaged head. These studies established that the portal is required throughout the DNA packaging process, with different domains participating at different stages of genome packaging. © 2013.

  7. Extrahepatic portal vein obstruction and portal vein thrombosis in special situations: Need for a new classification.

    PubMed

    Wani, Zeeshan A; Bhat, Riyaz A; Bhadoria, Ajeet S; Maiwall, Rakhi

    2015-01-01

    Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized.

  8. Extrahepatic Portal Vein Obstruction and Portal Vein Thrombosis in Special Situations: Need for a New Classification

    PubMed Central

    Wani, Zeeshan A.; Bhat, Riyaz A.; Bhadoria, Ajeet S.; Maiwall, Rakhi

    2015-01-01

    Extrahepatic portal vein obstruction is a vascular disorder of liver, which results in obstruction and cavernomatous transformation of portal vein with or without the involvement of intrahepatic portal vein, splenic vein, or superior mesenteric vein. Portal vein obstruction due to chronic liver disease, neoplasm, or postsurgery is a separate entity and is not the same as extrahepatic portal vein obstruction. Patients with extrahepatic portal vein obstruction are generally young and belong mostly to Asian countries. It is therefore very important to define portal vein thrombosis as acute or chronic from management point of view. Portal vein thrombosis in certain situations such as liver transplant and postsurgical/liver transplant period is an evolving area and needs extensive research. There is a need for a new classification, which includes all areas of the entity. In the current review, the most recent literature of extrahepatic portal vein obstruction is reviewed and summarized. PMID:26021771

  9. 1. West portal of the mudshed abutting the west portal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West portal of the mudshed abutting the west portal of Tunnel 5, view to the northwest, 135mm lens. The flat-roofed reinforced concrete mudsheds, rocksheds, and snowsheds are a common feature of the Natron Cutoff over the summit of the Cascades. With the railroad located on a sidehill bench cut into the precipitous slopes, the sheds protect the track from rock and mud slides, as well as from avalanches. With a solid wall on the uphill side and a series of columns on the downhill side, they form a gallery-like effect from within. This mudshed was built concurrent with the tunnel, in 1927. Though none of the mudsheds on the line are scheduled to be modified, this shed was documented as an integral element of Tunnel 5. - Southern Pacific Railroad Natron Cutoff, Tunnel 5, Milepost 545.2, McCredie Springs, Lane County, OR

  10. MyWelch: building an information portal system in a medical library environment.

    PubMed

    Zhang, Dongming; Zambrowicz, Caroline; Zhou, Hong; Roderer, Nancy

    2003-01-01

    MyWelch is a medical library portal system that users can use to create customized web sites that reflect their research needs and personal interests. In the MyWelch environment, faculty and students are empowered to take a greater role in identifying their needs and determining their requirements in the electronic environment. The portal system also facilitates interaction among library users and staff.

  11. SU-F-T-263: Dosimetric Characteristics of the Cine Acquisition Mode of An A-Si EPID

    SciTech Connect

    Bawazeer, O; Deb, P; Sarasanandarajah, S

    2016-06-15

    Purpose: To investigate the dosimetric characteristics of Varian a-Si-500 electronic portal imaging device (EPID) operated in cine mode particularly considering linearity with delivered dose, dose rate, field size, phantom thickness, MLC speed and common IMRT fields. Methods: The EPID that attached to a Varian Clinac 21iX linear accelerator, was irradiated with 6 and 18 MV using 600 MU/min. Image acquisition is controlled by the IAS3 software, Trigger delay was 6 ms, BeamOnDelay and FrameStartDelay were zero. Different frame rates were utilized. Cine mode response was calculated using MATLAB as summation of mean pixel values in a region of interest ofmore » the acquired images. The performance of cine mode was compared to integrated mode and dose measurements in water using CC13 ionization chamber. Results: Figure1 illustrates that cine mode has nonlinear response for small MU, when delivering 10 MU was about 0.5 and 0.64 for 6 and 18 MV respectively. This is because the missing acquired images that were calculated around four images missing in each delivery. With the increase MU the response became linear and comparable with integrated mode and ionization chamber within 2%. Figure 2 shows that cine mode has comparable response with integrated mode and ionization chamber within 2% with changing dose rate for 10 MU delivered. This indicates that the dose rate change has no effect on nonlinearity of cine mode response. Except nonlinearity, cine mode is well matched to integrated mode response within 2% for field size, phantom thickness, MLC speed dependences. Conclusion: Cine mode has similar dosimetric characteristics to integrated mode with open and IMRT fields, and the main limitation with cine mode is missing images. Therefore, the calibration of EPID images with this mode should be run with large MU, and when IMRT verification field has low MU, the correction for missing images are required.« less

  12. [Selective portal-systemic shunts for bleeding portal hypertension].

    PubMed

    Orozco, H; Mercado, M A; Takahashi, T; García-Tsao, G; Guevara, L; Hernandez-Ortiz, J; Tielve, M

    1990-07-01

    At the beginning of the seventies, we began to perform regularly selective shunts for the treatment of portal hypertension. In a 15 year period, 177 patients (155 with liver cirrhosis) were operated with three kinds of selective shunts: 128 with a Warren shunt, 29 with an end to end renosplenic shunt and 20 with a splenocaval shunt. 167 cases were operated in an elective fashion. The 15 years global operative mortality, was 14.4%. Operative mortality of the Child A patients, was 11.6%. Survival for the Child A group was 74.6% at 1 year, 68.2% at 5 years and 64.6% at 15 years. Incapacitating encephalopathy was observed in 6.9%, rebleeding 6.2% and shunt thrombosis in 6.2%. Portal vein alterations in the postoperative period were observed: in 13.3% a reduction in diameter ocurred and in 20.5%, thrombosis was recorded. It is concluded that when feasible, the selective shunts are the treatment of choice for portal hypertension in those patients with good liver function.

  13. Vertical flow chemical detection portal

    DOEpatents

    Linker, K.L.; Hannum, D.W.; Conrad, F.J.

    1999-06-22

    A portal apparatus is described for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow. 3 figs.

  14. Vertical flow chemical detection portal

    DOEpatents

    Linker, Kevin L.; Hannum, David W.; Conrad, Frank James

    1999-01-01

    A portal apparatus for screening objects or persons for the presence of trace amounts of chemical substances such as illicit drugs or explosives. The apparatus has a test space, in which a person may stand, defined by two generally upright sides spanned by a horizontal transom. One or more fans in the transom generate a downward air flow (uni-directional) within the test space. The air flows downwardly from a high pressure upper zone, past the object or person to be screened. Air moving past the object dislodges from the surface thereof both volatile and nonvolatile particles of the target substance. The particles are entrained into the air flow which continues flowing downward to a lower zone of reduced pressure, where the particle-bearing air stream is directed out of the test space and toward preconcentrator and detection components. The sides of the portal are specially configured to partially contain and maintain the air flow.

  15. Endoscopic treatments for portal hypertension.

    PubMed

    Lo, Gin-Ho

    2018-02-01

    Acute esophageal variceal hemorrhage is a dreaded complication of portal hypertension. Its management has evolved rapidly in recent years. Endoscopic therapy is often employed to arrest bleeding varices as well as to prevent early rebleeding. The combination of vasoconstrictor and endoscopic therapy is superior to vasoconstrictor or endoscopic therapy alone for control of acute esophageal variceal hemorrhage. After control of acute variceal bleeding, combination of banding ligation and beta-blockers is generally recommended to prevent variceal rebleeding. To prevent the catastrophic event of acute variceal bleeding, endoscopic banding ligation is an important tool in the prophylaxis of first bleeding. Endoscopic obturation with cyanoacrylate is usually utilized to arrest acute gastric variceal hemorrhage as well as to prevent rebleeding. It can be concluded that endoscopic therapies play a pivotal role in management of portal hypertensive bleeding.

  16. J-Plus Web Portal

    NASA Astrophysics Data System (ADS)

    Civera Lorenzo, Tamara

    2017-10-01

    Brief presentation about the J-PLUS EDR data access web portal (http://archive.cefca.es/catalogues/jplus-edr) where the different services available to retrieve images and catalogues data have been presented.J-PLUS Early Data Release (EDR) archive includes two types of data: images and dual and single catalogue data which include parameters measured from images. J-PLUS web portal offers catalogue data and images through several different online data access tools or services each suited to a particular need. The different services offered are: Coverage map Sky navigator Object visualization Image search Cone search Object list search Virtual observatory services: Simple Cone Search Simple Image Access Protocol Simple Spectral Access Protocol Table Access Protocol

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

    PubMed

    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

  18. Z-portal dark matter

    SciTech Connect

    Arcadi, Giorgio; Institute for Theoretical Physics, Georg-August University Göttingen, Friedrich-Hund-Platz 1, Göttingen, D-37077; Mambrini, Yann

    2015-03-11

    We propose to generalize the extensions of the Standard Model where the Z boson serves as a mediator between the Standard Model sector and the dark sector χ. We show that, like in the Higgs portal case, the combined constraints from the recent direct searches restrict severely the nature of the coupling of the dark matter to the Z boson and set a limit m{sub χ}≳200 GeV (except in a very narrow region around the Z-pole region). Using complementarity between spin dependent, spin independent and FERMI limits, we predict the nature of this coupling, more specifically the axial/vectorial ratio thatmore » respects a thermal dark matter coupled through a Z-portal while not being excluded by the current observations. We also show that the next generation of experiments of the type LZ or XENON1T will test Z-portal scenario for dark matter mass up to 2 TeV. The condition of a thermal dark matter naturally predicts the spin-dependent scattering cross section on the neutron to be σ{sub χn}{sup SD}≃10{sup −40} cm{sup 2}, which then becomes a clear prediction of the model and a signature testable in the near future experiments.« less

  19. Z-portal dark matter

    SciTech Connect

    Arcadi, Giorgio; Mambrini, Yann; Richard, Francois, E-mail: giorgio.arcadi@th.u-psud.fr, E-mail: yann.mambrini@th.u-psud.fr, E-mail: richard@lal.in2p3.fr

    2015-03-01

    We propose to generalize the extensions of the Standard Model where the Z boson serves as a mediator between the Standard Model sector and the dark sector χ. We show that, like in the Higgs portal case, the combined constraints from the recent direct searches restrict severely the nature of the coupling of the dark matter to the Z boson and set a limit m{sub χ} ∼> 200 GeV (except in a very narrow region around the Z-pole region). Using complementarity between spin dependent, spin independent and FERMI limits, we predict the nature of this coupling, more specifically the axial/vectorial ratio thatmore » respects a thermal dark matter coupled through a Z-portal while not being excluded by the current observations. We also show that the next generation of experiments of the type LZ or XENON1T will test Z-portal scenario for dark matter mass up to 2 TeV . The condition of a thermal dark matter naturally predicts the spin-dependent scattering cross section on the neutron to be σ{sup SD}{sub χn} ≅ 10{sup −40} cm{sup 2}, which then becomes a clear prediction of the model and a signature testable in the near future experiments.« less

  20. The Higgs portal above threshold

    DOE PAGES

    Craig, Nathaniel; Lou, Hou Keong; McCullough, Matthew; ...

    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. In this study, we systematically explore the collider signatures of singlet scalars produced via the Higgs Portal at the 14TeV LHC and a prospective 100TeV 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 o ff-shell Higgs. Assuming these scalars escape the detector, promising channels include missing energy inmore » association with vector boson fusion, monojets, and top pairs. In addition, 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.« less

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

    PubMed

    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.

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

    PubMed

    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 < 0.001). Our results suggest that the lesser omentum/aorta ratio has diagnostic value in pediatric portal hypertension.

  3. Military Portal, augmenting the U.S. Air Force Portal and DoD portal, Army,

    Science.gov Websites

    Troops-to-Teachers Program This portal page is designed so it can be copied to a hard drive, forwarded by aspect of the military. C'mon down and visit us online. If you make a copy of this page on your hard you put this file on your hard drive, you can modify it and add links of your own choosing ... such as

  4. Patient Portal Use and Experience Among Older Adults: Systematic Review

    PubMed Central

    2017-01-01

    Background The older adult population (65 years or older) in the United States is growing, and it is important for communities to consider ways to support the aging population. Patient portals and electronic personal health records (ePHRs) are technologies that could better serve populations with the highest health care needs, such as older adults. Objective The aim of this study was to assess the existing research landscape related to patient portal and ePHR use and experience among older adults and to understand the benefits and barriers to older adults’ use and adoption of patient portals and ePHRs. Methods We searched six pertinent bibliographic databases for papers, published from 2006 to 2016 and written in English, that focused on adults 60 years or older and their use of or experience with patient portals or ePHRs. We adapted preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines to review papers based on exclusion and inclusion criteria. We then applied thematic analysis to identify key themes around use, experience, and adoption. Results We retrieved 199 papers after an initial screening and removal of duplicate papers. Then we applied an inclusion and exclusion criteria, resulting in a final set of 17 papers that focused on 15 separate projects. The majority of papers described studies involving qualitative research, including interviews and focus groups. They looked at the experience and use of ePHRs and patient portals. Overall, we found 2 main barriers to use: (1) privacy and security and (2) access to and ability to use technology and the Internet. We found 2 facilitators: (1) technical assistance and (2) family and provider advice. We also reported on older adults’ experience, including satisfaction with the system and improvement of the quality of their health care. Several studies captured features that older adults wanted from these systems such as further assistance managing health-related tasks and contextual

  5. Congenital abnormalities associated with extrahepatic portal hypertension.

    PubMed Central

    Odièvre, M; Pigé, G; Alagille, D

    1977-01-01

    Congenital abnormalities were present in 12 out of 30 (40%) children with extrahepatic portal hypertension of unknown cause, but in only 2 out of 17 (12%) children with extnahepatic portal hypertension secondary to umbilical vein catheterization or omphalitis. The most frequent abnormalities in this series and in published reports were atrial septal defect, malformation of the biliary tract, and anomalous inferior vena cava. These findings are consistent with the view that some cases with extrahepatic portal hypertension are congenital in origin. PMID:869567

  6. Surgical implications of portal venous system malformation

    PubMed Central

    Marks, Charles

    1974-01-01

    The significance of congenital abnormalities in predisposing to portal hypertension and variceal haemorrhage needs to be remembered when these effects manifest in childhood, as portal venography will permit elucidation of the complicated congenital developmental abnormalities underlying the pathological condition and permit rational surgical amelioration. In the presence of portal hypertension the development of a collateral venous circulation may be represented by a hepatopetal or hepatofugal circulatory pattern and will closely parallel the developmental areas where portal and systemic venous circulations meet, being representative of the embryological anastomosis between the vitelloumbilical system and the posterior cardinal system of veins. ImagesFig. 3Fig. 5Fig. 6 PMID:4614690

  7. Binary synaptic connections based on memory switching in a-Si:H for artificial neural networks

    NASA Technical Reports Server (NTRS)

    Thakoor, A. P.; Lamb, J. L.; Moopenn, A.; Khanna, S. K.

    1987-01-01

    A scheme for nonvolatile associative electronic memory storage with high information storage density is proposed which is based on neural network models and which uses a matrix of two-terminal passive interconnections (synapses). It is noted that the massive parallelism in the architecture would require the ON state of a synaptic connection to be unusually weak (highly resistive). Memory switching using a-Si:H along with ballast resistors patterned from amorphous Ge-metal alloys is investigated for a binary programmable read only memory matrix. The fabrication of a 1600 synapse test array of uniform connection strengths and a-Si:H switching elements is discussed.

  8. A Semantically Enabled Portal for Facilitating the Public Service Provision

    NASA Astrophysics Data System (ADS)

    Loutas, Nikolaos; Giantsiou, Lemonia; Peristeras, Vassilios; Tarabanis, Konstantinos

    During the past years, governments have made significant efforts to improve both their internal processes and the services that they provide to citizens and businesses. These led to several successful e-Government applications (e.g., see www.epractice.eu). One of the most popular tools that was used by governments in order to modernize their services and make them accessible is e-Government portals, e.g., (Drigas et al. 2005), (Fang 2002). The main goals of such portals are: To make available complete, easy to understand, and structured information about public services and public administration's modus operandi, which will assist citizens during the service provision process. To facilitate the electronic execution of public services. Nevertheless, most of such efforts did not succeed. Gartner argues that most e-Government strategies have not achieved their objectives and have failed to trigger sustainable government transformation to greater efficiency and citizen-centricity (DiMaio 2007).

  9. SU-E-T-364: 6X FFF and 10X FFF Portal Dosimetry Output Factor Verification: Application for SRS/SBRT

    SciTech Connect

    Gulam, M; Bellon, M; Gopal, A

    2014-06-01

    Purpose: To enhance portal dosimetry of high dose rate SRS/SBRT plan verifications with extensive imager measurement of output factors (OF). Methods: Electronic portal image dosimetry (EPID), implemented on the Varian Edge allows for acquisition of its two energies: 6X FFF and 10 FFF (1400 and 2400 MU/min, respectively) at source to imager distance (SID) =100cm without imager saturation. Square and rectangular aSi OF following EPID calibration were obtained. Data taken was similar to that obtained during beam commissioning (of almost all field sizes from 1×1 to 15×15 and 20×20 cm{sup 2}, [Trilogy] and [Edge], respectively) to construct a table usingmore » the OF tool for use in the Portal Dosimetry Prediction Algorithm (PDIP v11). The Trilogy 6x SRS 1000 MU/min EPID data were taken at 140 SID. The large number of OF were obtained for comparison to that obtained with diode detectors and ion chambers (cc13 for >3×3 field size). As Edge PDIP verification is currently ongoing, EPID measurements of three SRS/SBRT plans for the Trilogy were taken and compared to results obtained prior to these measurements. Results: The relative difference output factors of field sizes 2×2 and higher compared to commissioning data were (mean+/-SD, [range]): Edge 6X (−1.9+/−2.9%, [−5.9%,3.1%]), Edge 10X (−0.7+/−1.2%, [− 3.3%,0.8%] and Trilogy (0.03+/−0.5%, [−1.4%,1.1%]) with EPID over predicting. The results for the 140 SID showed excellent agreement throughout except at the 1×1 to 1×15 and 15×1 field sizes where differences were: −10.6%, −6.0% and −5.8%. The differences were also most pronounced for the 1×1 at 100 SID. They were −7.4% and −11.5% for 6X and 10X, respectively. The Gamma (3%, 1mm) for three clinical plans improved by 8.7+/−1.8%. Conclusion: Results indicate that imager output factor measurements at any SID of high dose rate SRS/SBRT are quite reliable for portal dosimetry plan verification except for the smallest fields. This work was

  10. Fraud prevention in paying portal

    NASA Astrophysics Data System (ADS)

    Sandhu, P. S.; Senthilkumar, N. C.

    2017-11-01

    The purpose of presenting this paper is to give the idea to prevent the fraud in finance paying portals as fraud is increasing on daily basis and mostly in financial sector. So through this paper we are trying to prevent the fraud. This paper will give you the working algorithm through which you can able to prevent the fraud. Algorithm will work according to the spending amount of the user, which means that use will get categories into one of the low, medium, high or very high category.

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

    PubMed Central

    Herek, Duygu; Sungurtekin, Ugur

    2015-01-01

    Background Hepatic hydatid cysts rarely invade portal veins causing portal cavernomatosis as a secondary complication. Case Report 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). Conclusion 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. PMID:26730239

  12. Endovascular interventions for traumatic portal venous hemorrhage complicated by portal hypertension

    PubMed Central

    Sundarakumar, Dinesh Kumar; Smith, Crysela Mirta; Lopera, Jorge Enrique; Kogut, Matthew; Suri, Rajeev

    2013-01-01

    Life-threatening hemorrhage rarely occurs from the portal vein following blunt hepatic trauma. Traditionally, severe portal bleeding in this setting has been controlled by surgical techniques such as packing, ligation, and venorrhaphy. The presence of portal hypertension could potentially increase the amount of hemorrhage in the setting of blunt portal vein trauma making it more difficult to control. This case series describes the use of indirect carbon dioxide portography to identify portal hemorrhage. Furthermore, these cases illustrate attempted endovascular treatment utilizing a transjugular intrahepatic portosystemic shunt in one scenario and transmesocaval shunt coiling of a jejunal varix in the other. PMID:24179633

  13. Combined multifrequency EPR and DFT study of dangling bonds in a-Si:H

    NASA Astrophysics Data System (ADS)

    Fehr, M.; Schnegg, A.; Rech, B.; Lips, K.; Astakhov, O.; Finger, F.; Pfanner, G.; Freysoldt, C.; Neugebauer, J.; Bittl, R.; Teutloff, C.

    2011-12-01

    Multifrequency pulsed electron paramagnetic resonance (EPR) spectroscopy using S-, X-, Q-, and W-band frequencies (3.6, 9.7, 34, and 94 GHz, respectively) was employed to study paramagnetic coordination defects in undoped hydrogenated amorphous silicon (a-Si:H). The improved spectral resolution at high magnetic field reveals a rhombic splitting of the g tensor with the following principal values: gx=2.0079, gy=2.0061, and gz=2.0034, and shows pronounced g strain, i.e., the principal values are widely distributed. The multifrequency approach furthermore yields precise 29Si hyperfine data. Density functional theory (DFT) calculations on 26 computer-generated a-Si:H dangling-bond models yielded g values close to the experimental data but deviating hyperfine interaction values. We show that paramagnetic coordination defects in a-Si:H are more delocalized than computer-generated dangling-bond defects and discuss models to explain this discrepancy.

  14. Threshold Voltage Instability in A-Si:H TFTS and the Implications for Flexible Displays and Circuits

    DTIC Science & Technology

    2008-12-01

    and negative gate voltages with and without elevated drain voltages for FDC TFTs. Extending techniques used to localize hot electron degradation...in MOSFETs, experiments in our lab have localized the degradation of a-Si:H to the gate dielectric/a-Si:H channel interface [Shringarpure, et al...saturation, increased drain source current measured with the source and drain reversed indicates localization of ΔVth to the gate dielectric/amorphous

  15. Factors Affecting Faculty Web Portal Usability

    ERIC Educational Resources Information Center

    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…

  16. Bem vindo - Portal Brasileiro de Dados Abertos

    Science.gov Websites

    Pular para o conteúdo Portal do Governo Brasileiro Ir para o conteúdo 1 Ir para o menu 2 Ir para a busca 3 Ir para o rodapé 4 dados.gov.br Portal Brasileiro de Dados Abertos Enviar feed twitter CÃ

  17. Isocurvature constraints on portal couplings

    SciTech Connect

    Kainulainen, Kimmo; Nurmi, Sami; Vaskonen, Ville

    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 thenmore » 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.« less

  18. The BLUEPRINT Data Analysis Portal.

    PubMed

    Fernández, José María; de la Torre, Victor; Richardson, David; Royo, Romina; Puiggròs, Montserrat; Moncunill, Valentí; Fragkogianni, Stamatina; Clarke, Laura; Flicek, Paul; Rico, Daniel; Torrents, David; Carrillo de Santa Pau, Enrique; Valencia, Alfonso

    2016-11-23

    The impact of large and complex epigenomic datasets on biological insights or clinical applications is limited by the lack of accessibility by easy, intuitive, and fast tools. Here, we describe an epigenomics comparative cyber-infrastructure (EPICO), an open-access reference set of libraries to develop comparative epigenomic data portals. Using EPICO, large epigenome projects can make available their rich datasets to the community without requiring specific technical skills. As a first instance of EPICO, we implemented the BLUEPRINT Data Analysis Portal (BDAP). BDAP provides a desktop for the comparative analysis of epigenomes of hematopoietic cell types based on results, such as the position of epigenetic features, from basic analysis pipelines. The BDAP interface facilitates interactive exploration of genomic regions, genes, and pathways in the context of differentiation of hematopoietic lineages. This work represents initial steps toward broadly accessible integrative analysis of epigenomic data across international consortia. EPICO can be accessed at https://github.com/inab, and BDAP can be accessed at http://blueprint-data.bsc.es. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Straddle Carrier Radiation Portal Monitoring

    SciTech Connect

    Andersen, Eric S.; Samuel, Todd J.; Mullen, O Dennis

    2005-08-01

    U.S. Customs and Border Protection (CBP) is the primary enforcement agency protecting the nation’s ports of entry. CBP is enhancing its capability to interdict the illicit import of nuclear and radiological materials and devices that may be used by terrorists. Pacific Northwest National Laboratory (PNNL) is providing scientific and technical support to CBP in their goal to enable rapid deployment of nuclear and radiation detection systems at U. S. ports of entry to monitor 100% of the incoming international traffic and cargo while not adversely impacting the operations or throughput of the ports. The U.S. ports of entry include themore » following vectors: land border crossings, seaports, airports, rail crossings, and mail and express consignment courier facilities. U.S. Customs and Border Protection (CBP) determined that a screening solution was needed for Seaport cargo containers being transported by Straddle Carriers (straddle carriers). A stationary Radiation Portal Monitor (RPM) for Straddle Carriers (SCRPM) is needed so that cargo containers can be scanned while in transit under a Straddle Carrier. The Straddle Carrier Portal operational impacts were minimized by conducting a time-motion study at the Port, and adaptation of a Remotely Operated RPM (RO-RPM) booth concept that uses logical lighting schemes for traffic control, cameras, Optical Character Recognition, and wireless technology.« less

  20. Straddle carrier radiation portal monitoring

    NASA Astrophysics Data System (ADS)

    Andersen, Eric S.; Samuel, Todd J.; Mullen, O. Dennis

    2005-05-01

    U.S. Customs and Border Protection (CBP) is the primary enforcement agency protecting the nation"s ports of entry. CBP is enhancing its capability to interdict the illicit import of nuclear and radiological materials and devices that may be used by terrorists. Pacific Northwest National Laboratory (PNNL) is providing scientific and technical support to CBP in their goal to enable rapid deployment of nuclear and radiation detection systems at U. S. ports of entry to monitor 100% of the incoming international traffic and cargo while not adversely impacting the operations or throughput of the ports. The U.S. ports of entry include the following vectors: land border crossings, seaports, airports, rail crossings, and mail and express consignment courier facilities. U.S. Customs and Border Protection (CBP) determined that a screening solution was needed for Seaport cargo containers being transported by Straddle Carriers (straddle carriers). A stationary Radiation Portal Monitor (RPM) for Straddle Carriers (SCRPM) is needed so that cargo containers can be scanned while in transit under a Straddle Carrier. The Straddle Carrier Portal operational impacts were minimized by conducting a time-motion study at the Port, and adaptation of a Remotely Operated RPM (RO-RPM) booth concept that uses logical lighting schemes for traffic control, cameras, Optical Character Recognition, and wireless technology.

  1. Idiopathic noncirrhotic portal hypertension: current perspectives

    PubMed Central

    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. PMID:27555800

  2. Idiopathic noncirrhotic portal hypertension: current perspectives.

    PubMed

    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.

  3. Ultrasonography for Noninvasive Assessment of Portal Hypertension

    PubMed Central

    Maruyama, Hitoshi; Yokosuka, Osamu

    2017-01-01

    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. PMID:28267700

  4. Ultrasonography for Noninvasive Assessment of Portal Hypertension.

    PubMed

    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.

  5. Patient Portals and Patient Engagement: A State of the Science Review

    PubMed Central

    DeVito Dabbs, Annette; Curran, Christine R

    2015-01-01

    Background Patient portals (ie, electronic personal health records tethered to institutional electronic health records) are recognized as a promising mechanism to support greater patient engagement, yet questions remain about how health care leaders, policy makers, and designers can encourage adoption of patient portals and what factors might contribute to sustained utilization. Objective The purposes of this state of the science review are to (1) present the definition, background, and how current literature addresses the encouragement and support of patient engagement through the patient portal, and (2) provide a summary of future directions for patient portal research and development to meaningfully impact patient engagement. Methods We reviewed literature from 2006 through 2014 in PubMed, Ovid Medline, and PsycInfo using the search terms “patient portal” OR “personal health record” OR “electronic personal health record”. Final inclusion criterion dictated that studies report on the patient experience and/or ways that patients may be supported to make competent health care decisions and act on those decisions using patient portal functionality. Results We found 120 studies that met the inclusion criteria. Based on the research questions, explicit and implicit aims of the studies, and related measures addressed, the studies were grouped into five major topics (patient adoption, provider endorsement, health literacy, usability, and utility). We discuss the findings and conclusions of studies that address the five topical areas. Conclusions Current research has demonstrated that patients’ interest and ability to use patient portals is strongly influenced by personal factors such age, ethnicity, education level, health literacy, health status, and role as a caregiver. Health care delivery factors, mainly provider endorsement and patient portal usability also contribute to patient’s ability to engage through and with the patient portal. Future

  6. Clinician-Stakeholders' Perspectives on Using Patient Portals to Return Lynch Syndrome Screening Results.

    PubMed

    Korngiebel, Diane M; West, Kathleen M; Burke, Wylie

    2018-04-01

    Test results for genetic conditions, such as Lynch Syndrome (LS), have traditionally been returned by genetic counselors or other providers who can explain results implications and provide psychosocial support. Returning genetic results through an Electronic Health Record's patient portal may increase the efficiency of returning results and could activate patient follow-up; however, stakeholder input is necessary to determine acceptability and appropriate implementation for LS. Twenty interviews were conducted with clinicians from six specialties involved in LS screening that represent a range of settings. Data were analyzed using directed content analysis and thematic analysis across content categories. Participants felt that patient portals could supplement personal calls, but the potential sensitive nature of LS screening results indicated the need for caution. Others felt that LS results could be returned through portals if there were clear explanations of the result, reputable additional information available within the portal, urging follow up confirmatory testing, and a referral to a genetics specialist. Patient portals were seen as helpful for prompting patient follow-up and providing resources to notify at-risk family members. There is potential for patient portals to return LS screening and other genetic results, however we raise several issues to resolve before implementation is warranted.

  7. A Longitudinal Study of Undergraduate Students' Perceptions and Use Patterns of the University Libraries Web Portal: Does Information Literacy Instruction Play a Role?

    ERIC Educational Resources Information Center

    Chen, Yu-Hui

    2012-01-01

    As the availability of digital resources increased exponentially over the last two decades, academic libraries have heavily invested in electronic resources and made them accessible via library Web portals. Yet, underutilization of library Web portals is a common concern among academic libraries. According to the information systems (IS)…

  8. Use of a web portal among adult clinic patients seen for type 2 diabetes mellitus

    PubMed Central

    Coughlin, Steven S.; Heboyan, Vahé; Williams, Lovoria B.; Hatzigeorgiou, Christos

    2018-01-01

    Background To determine the number of adult clinic patients seen for type 2 diabetes mellitus (T2DM) at an academic medical center and to examine characteristics of those who had or had not registered for a web portal. Methods Electronic records were reviewed to identify web portal registration by patients treated for T2DM by age, sex, race and Hispanic ethnicity, and service (General Internal Medicine, Endocrinology). Results A total of 1,401 patients with T2DM were seen in General Internal Medicine and Endocrinology outpatient clinics. Less than one third (32%) had registered for the web portal. Women were more likely to have registered for the web portal than men [odds ratio (OR) =1.25; 95% CI, 0.99–1.57; P<0.063]. Black patients were less likely to have registered than whites (OR =0.40; 95% CI, 0.31–0.51; P<0.001). Patients who were 18–25 years of age were less likely to have registered for the web portal, along with those who were 56 to 60 and >66 years of age. In multivariate analysis, a statistically significant association was observed between web portal registration and General Internal Medicine clinic vs. Endocrinology clinic (OR =2.96, P<0.001). Inverse associations were observed with age >18–25 years, male sex (adjusted OR =0.71, P=0.006), and Black race (OR =0.33, P<0.001). Conclusions Additional research is needed to identify portal design features that improve glycemic control and interventions that will increase use of patient portals, especially among Black patients with T2DM and those with low health literacy or computer literacy. PMID:29377041

  9. Use of a web portal among adult clinic patients seen for type 2 diabetes mellitus.

    PubMed

    Coughlin, Steven S; Heboyan, Vahé; Williams, Lovoria B; Hatzigeorgiou, Christos

    2018-01-01

    To determine the number of adult clinic patients seen for type 2 diabetes mellitus (T2DM) at an academic medical center and to examine characteristics of those who had or had not registered for a web portal. Electronic records were reviewed to identify web portal registration by patients treated for T2DM by age, sex, race and Hispanic ethnicity, and service (General Internal Medicine, Endocrinology). A total of 1,401 patients with T2DM were seen in General Internal Medicine and Endocrinology outpatient clinics. Less than one third (32%) had registered for the web portal. Women were more likely to have registered for the web portal than men [odds ratio (OR) =1.25; 95% CI, 0.99-1.57; P<0.063]. Black patients were less likely to have registered than whites (OR =0.40; 95% CI, 0.31-0.51; P<0.001). Patients who were 18-25 years of age were less likely to have registered for the web portal, along with those who were 56 to 60 and >66 years of age. In multivariate analysis, a statistically significant association was observed between web portal registration and General Internal Medicine clinic vs . Endocrinology clinic (OR =2.96, P<0.001). Inverse associations were observed with age >18-25 years, male sex (adjusted OR =0.71, P=0.006), and Black race (OR =0.33, P<0.001). Additional research is needed to identify portal design features that improve glycemic control and interventions that will increase use of patient portals, especially among Black patients with T2DM and those with low health literacy or computer literacy.

  10. Patient Portal Use and Blood Pressure Control in Newly Diagnosed Hypertension.

    PubMed

    Manard, William; Scherrer, Jeffrey F; Salas, Joanne; Schneider, F David

    2016-01-01

    Current evidence that patient portal use improves disease management is inconclusive. Randomized controlled trials have found no benefit of Web-based patient-provider communication for blood pressure (BP) control, but patients from these studies were not selected for uncontrolled hypertension, nor did measures of portal use occur in a real-world setting, as captured in the electronic medical record. This study determined whether patient portal use by patients with treated, incident hypertension was associated with achieving BP control. Between 2008 to 2010, 1571 patients with an incident hypertension diagnosis, ages 21 to >89 years, were identified from an academic medical center primary care patient data registry. Cox proportional hazard models were computed to estimate the association between portal use and incident BP control during follow-up (2011-2015), before and after adjusting for covariates. Covariates included sociodemographics, smoking, obesity and other physical and mental health comorbidities, and volume of health care utilization. After adjusting for age, portal users were more likely than nonusers to achieve BP control (hazard ratio, 1.24; 95% confidence interval, 1.06-1.45). After adjustment for sociodemographics, portal use was no longer associated with BP control (hazard ratio, 0.98; 95% confidence interval, 0.83-1.16). Patient sociodemographic factors, including race, sex, and socioeconomic status, account for the observation that portal use leads to BP control among persons with newly diagnosed hypertension. Further research is warranted to determine whether there are benefits of portal use for other chronic conditions. © Copyright 2016 by the American Board of Family Medicine.

  11. Encouraging Patient Portal Use in the Patient-Centered Medical Home: Three Stakeholder Perspectives.

    PubMed

    Fix, Gemmae M; Hogan, Timothy P; Amante, Daniel J; McInnes, D Keith; Nazi, Kim M; Simon, Steven R

    2016-11-22

    Health care organizations are increasingly offering patients access to their electronic medical record and the ability to communicate with their providers through Web-based patient portals, thus playing a prominent role within the patient-centered medical home (PCMH). However, despite enthusiasm, adoption remains low. We examined factors in the PCMH context that may affect efforts to improve enrollment in a patient portal. Using a sociotechnical approach, we conducted qualitative, semistructured interviews with patients and providers from 3 primary care clinics and with national leaders from across a large integrated health care system. We gathered perspectives and analyzed data from 4 patient focus groups and one-on-one interviews with 1 provider from each of 3 primary care clinics and 10 program leaders. We found that leaders were focused on marketing in primary care, whereas patients and providers were often already aware of the portal. In contrast, both patients and providers cited administrative and logistical barriers impeding enrollment. Further, although leadership saw the PCMH as the logical place to focus enrollment efforts, providers and patients were more circumspect and expressed concern about how the patient portal would affect their practice and experience of care. Further, some providers expressed ambivalence about patients using the portal. Despite absence of consensus on how and where to encourage portal adoption, there was wide agreement that promoting enrollment was a worthwhile goal. Patients, clinicians, and national leaders agreed that efforts were needed to increase enrollment in the patient portal. Opinions diverged regarding the suitability of the PCMH and, specifically, the primary care clinic for promoting patient portal enrollment. Policymakers should consider diverse stakeholder perspectives in advance of interventions to increase technology adoption. ©Gemmae M Fix, Timothy P Hogan, Daniel J Amante, D Keith McInnes, Kim M Nazi, Steven

  12. Encouraging Patient Portal Use in the Patient-Centered Medical Home: Three Stakeholder Perspectives

    PubMed Central

    2016-01-01

    Background Health care organizations are increasingly offering patients access to their electronic medical record and the ability to communicate with their providers through Web-based patient portals, thus playing a prominent role within the patient-centered medical home (PCMH). However, despite enthusiasm, adoption remains low. Objective We examined factors in the PCMH context that may affect efforts to improve enrollment in a patient portal. Methods Using a sociotechnical approach, we conducted qualitative, semistructured interviews with patients and providers from 3 primary care clinics and with national leaders from across a large integrated health care system. Results We gathered perspectives and analyzed data from 4 patient focus groups and one-on-one interviews with 1 provider from each of 3 primary care clinics and 10 program leaders. We found that leaders were focused on marketing in primary care, whereas patients and providers were often already aware of the portal. In contrast, both patients and providers cited administrative and logistical barriers impeding enrollment. Further, although leadership saw the PCMH as the logical place to focus enrollment efforts, providers and patients were more circumspect and expressed concern about how the patient portal would affect their practice and experience of care. Further, some providers expressed ambivalence about patients using the portal. Despite absence of consensus on how and where to encourage portal adoption, there was wide agreement that promoting enrollment was a worthwhile goal. Conclusions Patients, clinicians, and national leaders agreed that efforts were needed to increase enrollment in the patient portal. Opinions diverged regarding the suitability of the PCMH and, specifically, the primary care clinic for promoting patient portal enrollment. Policymakers should consider diverse stakeholder perspectives in advance of interventions to increase technology adoption. PMID:27876686

  13. PSUP: A Planetary SUrface Portal

    NASA Astrophysics Data System (ADS)

    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

  14. The Portal to the Universe an IYA2009 Cornerstone Project

    NASA Astrophysics Data System (ADS)

    Lindberg Christensen, Lars; Gay, P.; IYA2009 TPTTU Cornerstone Task Group

    2008-05-01

    The science of astronomy is extremely fast moving, and delivers new results on a daily basis, often in the form of spectacular news, images of forms and shapes not seen anywhere else, enhanced by illustrations and animations. Public astronomy communication has to develop apace with the other players in the mass market for electronic information such as the gaming and entertainment industries. The problem today is not so much the availability of excellent astronomy multimedia resources for use in education, outreach and the like, but rather finding and accessing these materials. The Portal to the Universe (TPTTU) seeks to fix this problem. The Portal to the Universe (TPTTU) is an IYA2009 Cornerstone project that will feature a comprehensive directory of observatories, facilities, astronomical societies, amateur astronomy societies, space artists, science communication universities, as well as news-, image-, event- and video- aggregators and Web 2.0 collaborative tools for astronomy multimedia community interaction. The Portal will enable innovative access to, and vastly multiply the use of, astronomy multimedia resources - including news, images, videos, events, podcasts, vodcasts etc. as a selective aggregator with a non-painful editorial mechanism in place. This talk will discuss the plans for the TPTTU content as well as the technology and editorial choices behind the scenes.

  15. Probing the fermionic Higgs portal at lepton colliders

    DOE PAGES

    Fedderke, Michael A.; Lin, Tongyan; Wang, Lian -Tao

    2016-04-26

    Here, we study the sensitivity of future electron-positron colliders to UV completions of the fermionic Higgs portal operator H †Hχ¯χ. Measurements of precision electroweak S and T parameters and the e +e – → Zh cross-section at the CEPC, FCC-ee, and ILC are considered. The scalar completion of the fermionic Higgs portal is closely related to the scalar Higgs portal, and we summarize existing results. We devote the bulk of our analysis to a singlet-doublet fermion completion. Assuming the doublet is sufficiently heavy, we construct the effective field theory (EFT) at dimension-6 in order to compute contributions to the observables.more » We also provide full one-loop results for S and T in the general mass parameter space. In both completions, future precision measurements can probe the new states at the (multi-)TeV scale, beyond the direct reach of the LHC.« less

  16. Probing the fermionic Higgs portal at lepton colliders

    SciTech Connect

    Fedderke, Michael A.; Lin, Tongyan; Wang, Lian -Tao

    Here, we study the sensitivity of future electron-positron colliders to UV completions of the fermionic Higgs portal operator H †Hχ¯χ. Measurements of precision electroweak S and T parameters and the e +e – → Zh cross-section at the CEPC, FCC-ee, and ILC are considered. The scalar completion of the fermionic Higgs portal is closely related to the scalar Higgs portal, and we summarize existing results. We devote the bulk of our analysis to a singlet-doublet fermion completion. Assuming the doublet is sufficiently heavy, we construct the effective field theory (EFT) at dimension-6 in order to compute contributions to the observables.more » We also provide full one-loop results for S and T in the general mass parameter space. In both completions, future precision measurements can probe the new states at the (multi-)TeV scale, beyond the direct reach of the LHC.« less

  17. Freeze-in through portals

    SciTech Connect

    Blennow, Mattias; Fernandez-Martínez, Enrique; Zaldívar, Bryan, E-mail: emb@kth.se, E-mail: enrique.fernandez-martinez@uam.es, E-mail: b.zaldivar.m@csic.es

    2014-01-01

    The popular freeze-out paradigm for Dark Matter (DM) production, relies on DM-baryon couplings of the order of the weak interactions. However, different search strategies for DM have failed to provide a conclusive evidence of such (non-gravitational) interactions, while greatly reducing the parameter space of many representative models. This motivates the study of alternative mechanisms for DM genesis. In the freeze-in framework, the DM is slowly populated from the thermal bath while never reaching equilibrium. In this work, we analyse in detail the possibility of producing a frozen-in DM via a mediator particle which acts as a portal. We give analyticalmore » estimates of different freeze-in regimes and support them with full numerical analyses, taking into account the proper distribution functions of bath particles. Finally, we constrain the parameter space of generic models by requiring agreement with DM relic abundance observations.« less

  18. Portal hydatid with secondary cavernomatosis.

    PubMed

    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.

  19. From Prototype to Production: Lessons Learned from the Evolution of an EHR Educational Portal

    PubMed Central

    Borycki, Elizabeth M.; Armstrong, Brian; Kushniruk, Andre W.

    2009-01-01

    The use of electronic health records is rapidly increasing. However, the integration of this technology into the education of health professionals and health informaticians has largely remained to be explored. In this paper we describe an approach to providing remote access to electronic health records for use in health professional and health informatics education at the undergraduate and graduate levels. The University of Victoria EHR Educational Portal was designed by the authors to allow for remote Web-based access by students to a range of systems hosted on the portal. Architectural considerations and the evolution of the portal structure from prototype to production system are described. The paper also describes our initial applications of the approach in integrating EHRs into nursing, medical and health informatics educational programs. PMID:20351822

  20. Traumatic injury to the portal vein.

    PubMed Central

    Mattox, K L; Espada, R; Beall, A R

    1975-01-01

    Traumatic injuries to the upper abdominal vasculature pose difficult management problems related to both exposure and associated injuries. Among those injuries that are more difficult to manage are those involving the portal vein. While occurring rarely, portal vein injuries require specific therapeutic considerations. Between January, 1968, and July, 1974, over 2000 patients were treated operatively for abdominal trauma at the Ben Taub General Hospital. Among these patients, 22 had injury to the portal vein. Seventeen portal vein injuries were secondary to gunshot wounds, 3 to stab wounds, and 2 to blunt trauma. Associated injuries to the inferior vena cava, pancreas, liver and bile ducts were common. Three patients had associated abdominal aortic injuries, two with acute aorto-caval fistulae. Nine patients died from from failure to control hemorrhage. Eleven were long-term survivors, including two who required pancreataico-duodenectomy as well as portal venorrhaphy. Late complications were rare. The operative approach to patients with traumatic injuries to multiple organs in the upper abdomen, including the portal vein, requires aggressive management and predetermined sequential methods of repair. In spite of innumerable associated injuries, portal vein injuries can be successfully managed in a significant number of patients using generally available surgical techniques and several adjunctive maneuvers. PMID:1130870

  1. BSD Portals for LINUX 2.0

    NASA Technical Reports Server (NTRS)

    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.

  2. Portal vein aneurysm: What to know.

    PubMed

    Laurenzi, Andrea; Ettorre, Giuseppe Maria; Lionetti, Raffaella; Meniconi, Roberto Luca; Colasanti, Marco; Vennarecci, Giovanni

    2015-11-01

    Portal vein aneurysm is an unusual vascular dilatation of the portal vein, which was first described by Barzilai and Kleckner in 1956 and since then less than 200 cases have been reported. The aim of this article is to provide an overview of the international literature to better clarify various aspects of this rare nosological entity and provide clear evidence-based summary, when available, of the clinical and surgical management. A systematic literature search of the Pubmed database was performed for all articles related to portal vein aneurysm. All articles published from 1956 to 2014 were examined for a total of 96 reports, including 190 patients. Portal vein aneurysm is defined as a portal vein diameter exceeding 1.9 cm in cirrhotic patients and 1.5 cm in normal livers. It can be congenital or acquired and portal hypertension represents the main cause of the acquired version. Surgical indication is considered in case of rupture, thrombosis or symptomatic aneurysms. Aneurysmectomy and aneurysmorrhaphy are considered in patients with normal liver, while shunt procedures or liver transplantation are the treatment of choice in case of portal hypertension. Being such a rare vascular entity its management should be reserved to high-volume tertiary hepato-biliary centres. Copyright © 2015 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  3. Patient portals and broadband internet inequality.

    PubMed

    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  < .0001) and sending messages to providers (OR = 1.15, 95%CI, 1.09-1.14, P  < .0001) were associated with neighborhood broadband 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

  4. [Management of ascites due to portal hypertension].

    PubMed

    Godat, S; Antonino, A T; Dehlavi, M-A; Moradpour, D; Doerig, C

    2012-09-05

    Portal hypertension is regularly encountered by the general practitioner. It is defined by an elevation of the porto-systemic pressure gradient, with complications such as ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, variceal bleeding, hypersplenism, hepatopulmonary syndrome or hepatic encephalopathy occuring when a significant elevation of this gradient is reached. Cirrhosis is the primary cause of portal hypertension in industrialized countries. Symptomatic portal hypertension carries a poor prognosis. Management should be initiated rapidly, including the identification and correction of any reversible underlying condition. Liver transplantation should be considered in advanced cases.

  5. Abernethy malformation with portal vein aneurysm.

    PubMed

    Kumar, Atin; Kumar, Jyoti; Aggarwal, Rakesh; Srivastava, Siddharth

    2008-09-01

    We present the case of a 24-year-old man who was incidentally diagnosed with congenital extrahepatic portosystemic shunt with portal vein aneurysm during an investigation for non-specific abdominal pain. These are rare anomalies, and to the best of our knowledge, this is the first case reported with both anomalies associated together. Ultrasound, including color Doppler, computed tomography, and magnetic resonance imaging were performed which revealed a side-to-side shunt between the extrahepatic portal vein and the inferior vena cava, with aneurysmal fusiform dilatation of the proximal intrahepatic portal vein which ended abruptly. Etiology, clinical significance, and management strategies with regard to these abnormalities are discussed.

  6. Distinct DNA exit and packaging portals in the virus Acanthamoeba polyphaga mimivirus.

    PubMed

    Zauberman, Nathan; Mutsafi, Yael; Halevy, Daniel Ben; Shimoni, Eyal; Klein, Eugenia; Xiao, Chuan; Sun, Siyang; Minsky, Abraham

    2008-05-13

    Icosahedral double-stranded DNA viruses use a single portal for genome delivery and packaging. The extensive structural similarity revealed by such portals in diverse viruses, as well as their invariable positioning at a unique icosahedral vertex, led to the consensus that a particular, highly conserved vertex-portal architecture is essential for viral DNA translocations. Here we present an exception to this paradigm by demonstrating that genome delivery and packaging in the virus Acanthamoeba polyphaga mimivirus occur through two distinct portals. By using high-resolution techniques, including electron tomography and cryo-scanning electron microscopy, we show that Mimivirus genome delivery entails a large-scale conformational change of the capsid, whereby five icosahedral faces open up. This opening, which occurs at a unique vertex of the capsid that we coined the "stargate", allows for the formation of a massive membrane conduit through which the viral DNA is released. A transient aperture centered at an icosahedral face distal to the DNA delivery site acts as a non-vertex DNA packaging portal. In conjunction with comparative genomic studies, our observations imply a viral packaging pathway akin to bacterial DNA segregation, which might be shared by diverse internal membrane-containing viruses.

  7. Distinct DNA Exit and Packaging Portals in the Virus Acanthamoeba polyphaga mimivirus

    PubMed Central

    Zauberman, Nathan; Mutsafi, Yael; Halevy, Daniel Ben; Shimoni, Eyal; Klein, Eugenia; Xiao, Chuan; Sun, Siyang; Minsky, Abraham

    2008-01-01

    Icosahedral double-stranded DNA viruses use a single portal for genome delivery and packaging. The extensive structural similarity revealed by such portals in diverse viruses, as well as their invariable positioning at a unique icosahedral vertex, led to the consensus that a particular, highly conserved vertex-portal architecture is essential for viral DNA translocations. Here we present an exception to this paradigm by demonstrating that genome delivery and packaging in the virus Acanthamoeba polyphaga mimivirus occur through two distinct portals. By using high-resolution techniques, including electron tomography and cryo-scanning electron microscopy, we show that Mimivirus genome delivery entails a large-scale conformational change of the capsid, whereby five icosahedral faces open up. This opening, which occurs at a unique vertex of the capsid that we coined the “stargate”, allows for the formation of a massive membrane conduit through which the viral DNA is released. A transient aperture centered at an icosahedral face distal to the DNA delivery site acts as a non-vertex DNA packaging portal. In conjunction with comparative genomic studies, our observations imply a viral packaging pathway akin to bacterial DNA segregation, which might be shared by diverse internal membrane–containing viruses. PMID:18479185

  8. Percutaneous Portal Vein Access and Transhepatic Tract Hemostasis

    PubMed Central

    Saad, Wael E. A.; Madoff, David C.

    2012-01-01

    Percutaneous portal vein interventions require minimally invasive access to the portal venous system. Common approaches to the portal vein include transjugular hepatic vein to portal vein access and direct transhepatic portal vein access. A major concern of the transhepatic route is the risk of postprocedural bleeding, which is increased when patients are anticoagulated or receiving pharmaceutical thrombolytic therapy. Thus percutaneous portal vein access and subsequent closure are important technical parts of percutaneous portal vein procedures. At present, various techniques have been used for either portal access or subsequent transhepatic tract closure and hemostasis. Regardless of the method used, meticulous technique is required to achieve the overall safety and effectiveness of portal venous procedures. This article reviews the various techniques of percutaneous transhepatic portal vein access and the various closure and hemostatic methods used to reduce the risk of postprocedural bleeding. PMID:23729976

  9. Zolmitriptan: a novel portal hypotensive agent which synergizes with propranolol in lowering portal pressure.

    PubMed

    Reboredo, Mercedes; Chang, Haisul C Y; Barbero, Roberto; Rodríguez-Ortigosa, Carlos M; Pérez-Vizcaíno, Francisco; Morán, Asunción; García, Mónica; Banales, Jesús M; Carreño, Norberto; Alegre, Félix; Herrero, Ignacio; Quiroga, Jorge; Prieto, Jesús; Sangro, Bruno

    2013-01-01

    Only a limited proportion of patients needing pharmacological control of portal hypertension are hemodynamic responders to propranolol. Here we analyzed the effects of zolmitriptan on portal pressure and its potential interaction with propranolol. ZOLMITRIPTAN, PROPRANOLOL OR BOTH WERE TESTED IN TWO RAT MODELS OF PORTAL HYPERTENSION: common bile duct ligation (CBDL) and CCl4-induced cirrhosis. In these animals we measured different hemodynamic parameters including portal venous pressure, arterial renal flow, portal blood flow and cardiac output. We also studied the changes in superior mesenteric artery perfusion pressure and in arterial wall cAMP levels induced by zolmitriptan, propranolol or both. Moreover, we determined the effect of splanchnic sympathectomy on the response of PVP to zolmitriptan. In both models of portal hypertension zolmitriptan induced a dose-dependent transient descent of portal pressure accompanied by reduction of portal flow with only slight decrease in renal flow. In cirrhotic rats, splanchnic sympathectomy intensified and prolonged zolmitriptan-induced portal pressure descent. Also, propranolol caused more intense and durable portal pressure fall when combined with zolmitriptan. Mesenteric artery perfusion pressure peaked for about 1 min upon zolmitriptan administration but showed no change with propranolol. However propranolol enhanced and prolonged the elevation in mesenteric artery perfusion pressure induced by zolmitriptan. In vitro studies showed that propranolol prevented the inhibitory effects of β2-agonists on zolmitriptan-induced vasoconstriction and the combination of propranolol and zolmitriptan significantly reduced the elevation of cAMP caused by β2-agonists. Zolmitriptan reduces portal hypertension and non-selective beta-blockers can improve this effect. Combination therapy deserves consideration for patients with portal hypertension failing to respond to non-selective beta-blockers.

  10. Cavernous Transformation of Portal Vein Secondary to Portal Vein Thrombosis: A Case Report

    PubMed Central

    Ramos, Radhames; Park, Yoojin; Shazad, Ghulamullah; A.Garcia, Christine; Cohen, Ronny

    2012-01-01

    There are few reported cases of cavernous transformation of the portal vein (CTPV) in adults. We present a case of a 58 year-old male who was found to have this complication due to portal vein thrombosis (PVT). A 58-year old African American male with chronic alcohol and tobacco use presented with a 25-day history of weakness, generalized malaise, nausea and vomiting associated with progressively worsening anorexia and weight loss. The patient was admitted for severe anemia in conjunction with abnormal liver function tests and electrolyte abnormalities, and to rule out end stage liver disease or hepatic malignancy. The work-up for anemia showed no significant colon abnormalities, cholecystitis, liver cirrhosis, or liver abnormalities but could not rule out malignancy. An esophageogastroduodenoscopy (EGD) was suspicious for a mass compressing the stomach and small bowel. After further work-up, the hepatic mass has been diagnosed as a cavernous transformation of the portal vein (CTPV), a very rare complication of portal vein thrombosis (PVT). Cavernous Transformation of the Portal Vein (CTPV) is a rare and incurable complication of portal vein thrombosis (PVT) that should be considered as one of the differential diagnoses of a hepatic mass. Keywords Cavernous transformation of the portal vein; Portal vein thrombosis; Portal hypertension; Hyperbilirubinemia; Hepatic mass PMID:22383935

  11. The International Human Epigenome Consortium Data Portal.

    PubMed

    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.

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

    PubMed

    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.

  13. The Fukushima Daiichi Accident Study Information Portal

    SciTech Connect

    Shawn St. Germain; Curtis Smith; David Schwieder

    This paper presents a description of The Fukushima Daiichi Accident Study Information Portal. The Information Portal was created by the Idaho National Laboratory as part of joint NRC and DOE project to assess the severe accident modeling capability of the MELCOR analysis code. The Fukushima Daiichi Accident Study Information Portal was created to collect, store, retrieve and validate information and data for use in reconstructing the Fukushima Daiichi accident. In addition to supporting the MELCOR simulations, the Portal will be the main DOE repository for all data, studies and reports related to the accident at the Fukushima Daiichi nuclear powermore » station. The data is stored in a secured (password protected and encrypted) repository that is searchable and accessible to researchers at diverse locations.« less

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

    PubMed

    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.

  15. 23. INCLINED END POST / VERTICAL / DIAGONAL / PORTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. INCLINED END POST / VERTICAL / DIAGONAL / PORTAL BRACING DETAIL. VIEW TO SOUTHEAST. - Abraham Lincoln Memorial Bridge, Spanning Missouri River on Highway 30 between Nebraska & Iowa, Blair, Washington County, NE

  16. [Portal vein thrombosis associated with hepatic encephalopathy].

    PubMed

    Iwatani, Nao; Inatomi, Yuichiro; Yonehara, Toshiro; Fujioka, Shodo; Hashimoto, Yoichiro; Hirano, Teruyuki; Uchino, Makoto

    2005-03-01

    A 54-year-old man who had been administered chlormadinone acetate 3 months after prostatectomy for prostate cancer, acutely developed disorientation and memory disturbance. Six days later, he experienced high grade fever and epigastralgia. He was suspected to have hepatic encephalopathy, because the Fischer ratio was low although serum ammonia level remained normal. Further examinations including abdominal echography and CT scan disclosed a thrombus extending from the portal vein to the superior mesenteric vein together with abnormal collateral vessels originating from the portal vein. He was successfully treated with warfarin potassium, urokinase and heparin sodium. It was suggested that the patient developed hepatic encephalopathy due to portal-systemic circulation shunting secondary to portal vein thrombosis.

  17. The energy gap in a-Si 1 - xC g: H alloys

    NASA Astrophysics Data System (ADS)

    Valladares, Ariel A.; Valladares, Alexander; Enrique Sansores, L.; Nelis, Mary Ann Me

    1997-02-01

    The electronic structure of amorphous tetrahedral clusters of the type a-Si 1 - xC g: H are studied using the pseudopotential SCF Hartree-Fock approximation. The reduced energy gap isgiven by Egr( x) - 1 + 0.84 x for x ⩽ 0.5, whereas experimentally Egr( x) = 1 + 0.96 x. For x ⩾ 0.5 the dip in the gap value reported experimentally is verified.

  18. Learning from Public Television and the Web: Positioning Continuing Education as a Knowledge Portal.

    ERIC Educational Resources Information Center

    Vedro, Steven R.

    1999-01-01

    Digital convergence--the merging of television and computing--challenges localized monopolies of public television and continuing education. Continuing educators can reposition themselves in the electronic marketplace by serving as an educational portal, bringing their strengths of "brand recognition," local customer base, and access to…

  19. The Journal Usage Statistics Portal (JUSP): Helping Libraries Measure Use and Impact

    ERIC Educational Resources Information Center

    Mihlrad, Leigh

    2012-01-01

    The Joint Usage Statistics Portal (JUSP) (jusp.mimas.ac.uk), created by five U.K. libraries in 2009, gives participating libraries a single point of access for electronic journal statistics. It provides its more than 160 participants, including 140+ academic libraries in the United Kingdom, as well as 21 publishers and 3 intermediaries, with…

  20. Web-Based Project Portfolio Management Portal Success: A Quantitative Investigation

    ERIC Educational Resources Information Center

    Excellent, Frendy

    2013-01-01

    Due to its centralized content-sharing features, a project portfolio management (PPM) portal enables vertical, as well as horizontal, electronic exchanges between project professionals. Such exchanges, if effective, may deliver an individual impact through improved project performance. Effectiveness engenders use and satisfaction, reflecting the…

  1. Idiopathic Noncirrhotic Portal Hypertension: An Appraisal

    PubMed Central

    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

  2. Microprocessing of ITO and a-Si thin films using ns laser sources

    NASA Astrophysics Data System (ADS)

    Molpeceres, C.; Lauzurica, S.; Ocaña, J. L.; Gandía, J. J.; Urbina, L.; Cárabe, J.

    2005-06-01

    Selective ablation of thin films for the development of new photovoltaic panels and sensoring devices based on amorphous silicon (a-Si) is an emerging field, in which laser micromachining systems appear as appropriate tools for process development and device fabrication. In particular, a promising application is the development of purely photovoltaic position sensors. Standard p-i-n or Schottky configurations using transparent conductive oxides (TCO), a-Si and metals are especially well suited for these applications, appearing selective laser ablation as an ideal process for controlled material patterning and isolation. In this work a detailed study of laser ablation of a widely used TCO, indium-tin-oxide (ITO), and a-Si thin films of different thicknesses is presented, with special emphasis on the morphological analysis of the generated grooves. Excimer (KrF, λ = 248 nm) and DPSS lasers (λ = 355 and λ = 1064 nm) with nanosecond pulse duration have been used for material patterning. Confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM) techniques have been applied for the characterization of the ablated grooves. Additionally, process parametric windows have been determined in order to assess this technology as potentially competitive to standard photolithographic processes. The encouraging results obtained, with well-defined ablation grooves having thicknesses in the order of 10 µm both in ITO and in a-Si, open up the possibility of developing a high-performance double Schottky photovoltaic matrix position sensor.

  3. 2. West portal of Tunnel 35, view to east, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 35, view to east, 135mm lens with electronic flash fill. Note the notched wingwalls that support steel posts of entrance snowshed; these would have originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 35, Milepost 176.62, Yuba Pass, Nevada County, CA

  4. 2. West portal of Tunnel 39, view to east, 135mm ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 39, view to east, 135mm lens with electronic flash fill. Note the notched wingwalls that support steel posts of entrance snowshed; these would have originally held timber posts of the original timber snowsheds, miles of which once enclosed and protected the railroad from the ravages of Sierra winters. Note also that these tunnels, built in the 1920s, have dispensed with any use of stone masonry, and instead have all-concrete portals. - Central Pacific Transcontinental Railroad, Tunnel No. 39, Milepost 180.95, Cisco, Placer County, CA

  5. SU-E-J-15: Automatically Detect Patient Treatment Position and Orientation in KV Portal Images

    SciTech Connect

    Qiu, J; Yang, D

    2015-06-15

    Purpose: In the course of radiation therapy, the complex information processing workflow will Result in potential errors, such as incorrect or inaccurate patient setups. With automatic image check and patient identification, such errors could be effectively reduced. For this purpose, we developed a simple and rapid image processing method, to automatically detect the patient position and orientation in 2D portal images, so to allow automatic check of positions and orientations for patient daily RT treatments. Methods: Based on the principle of portal image formation, a set of whole body DRR images were reconstructed from multiple whole body CT volume datasets,more » and fused together to be used as the matching template. To identify the patient setup position and orientation shown in a 2D portal image, the 2D portal image was preprocessed (contrast enhancement, down-sampling and couch table detection), then matched to the template image so to identify the laterality (left or right), position, orientation and treatment site. Results: Five day’s clinical qualified portal images were gathered randomly, then were processed by the automatic detection and matching method without any additional information. The detection results were visually checked by physicists. 182 images were correct detection in a total of 200kV portal images. The correct rate was 91%. Conclusion: The proposed method can detect patient setup and orientation quickly and automatically. It only requires the image intensity information in KV portal images. This method can be useful in the framework of Electronic Chart Check (ECCK) to reduce the potential errors in workflow of radiation therapy and so to improve patient safety. In addition, the auto-detection results, as the patient treatment site position and patient orientation, could be useful to guide the sequential image processing procedures, e.g. verification of patient daily setup accuracy. This work was partially supported by research grant

  6. Implications of Patient Portal Transparency in Oncology: Qualitative Interview Study on the Experiences of Patients, Oncologists, and Medical Informaticists.

    PubMed

    Alpert, Jordan M; Morris, Bonny B; Thomson, Maria D; Matin, Khalid; Brown, Richard F

    2018-03-26

    Providing patients with unrestricted access to their electronic medical records through patient portals has impacted patient-provider communication and patients' personal health knowledge. However, little is known about how patient portals are used in oncology. The aim of this study was to understand attitudes of the portal's adoption for oncology and to identify the advantages and disadvantages of using the portal to communicate and view medical information. In-depth semistructured interviews were conducted with 60 participants: 35 patients, 13 oncologists, and 12 medical informaticists. Interviews were recorded, transcribed, and thematically analyzed to identify critical incidents and general attitudes encountered by participants. Two primary themes were discovered: (1) implementation practices influence attitudes, in which the decision-making and execution process of introducing portals throughout the hospital did not include the input of oncologists. Lack of oncologists' involvement led to a lack of knowledge about portal functionality, such as not knowing the time period when test results would be disclosed to patients; (2) perceptions of portals as communication tools varies by user type, meaning that each participant group (patients, oncologists, and medical informaticists) had varied opinions about how the portal should be used to transmit and receive information. Oncologists and medical informaticists had difficulty understanding one another's culture and communication processes in their fields, while patients had preferences for how they would like to receive communication, but it largely depended upon the type of test being disclosed. The majority of patients (54%, 19/35) who participated in this study viewed lab results or scan reports via the portal before being contacted by a clinician. Most were relatively comfortable with this manner of disclosure but still preferred face-to-face or telephone communication. Findings from this study indicate that

  7. An Approach for harmonizing European Water Portals

    NASA Astrophysics Data System (ADS)

    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/

  8. Next Gen One Portal Usability Evaluation

    NASA Technical Reports Server (NTRS)

    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

  9. Electronics

    DTIC Science & Technology

    2001-01-01

    International Acer Incorporated, Hsin Chu, Taiwan Aerospace Industrial Development Corporation, Taichung, Taiwan American Institute of Taiwan, Taipei, Taiwan...Singapore and Malaysia .5 - 4 - The largest market for semiconductor products is the high technology consumer electronics industry that consumes up...Singapore, and Malaysia . A new semiconductor facility costs around $3 billion to build and takes about two years to become operational

  10. Innovative E-portal for prevention and therapeutic programme for treatment of the obesity and overweight in health-tourism

    NASA Astrophysics Data System (ADS)

    Zuzda, Jolanta G.; Półjanowicz, Wiesław; Latosiewicz, Robert; Borkowski, Piotr; Bierkus, Mirosław; Moska, Owidiusz

    2017-11-01

    Modern technologies enable overweight and obesity people to enjoy physical activity. We have developed electronic portal containing rotational exercises useful in fight against those disorders. Easy access is provided with QR codes placed on web-site and simply accessed with electronic personal equipment (smartphones). QR codes can also be printed and hanged in different places of health tourism facilities.

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

    PubMed

    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.

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

    PubMed Central

    2016-01-01

    Background 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. Objective 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. Methods 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. Results 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. Conclusions 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. PMID:27357641

  13. The MISTRALS programme data portal

    NASA Astrophysics Data System (ADS)

    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.

  14. The MISTRALS programme data portal

    NASA Astrophysics Data System (ADS)

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

    2015-04-01

    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. Data sets managed by different data centres (ICARE, IPSL, SEDOO, CORIOLIS) are available through interoperability protocols (OPeNDAP, xml requests...) or archive synchronisation. Every in situ data set is available in the native format, but the most commonly used data sets have been homogenized (property names, units, quality flags...) and inserted in a relational database, in order to enable accurate data selection, and download of different data sets in a shared format. At present the MISTRALS data portal enables to access about 550 datasets. It counts more than 600 registered users and about 100 data requests every month. The number of available datasets is increasing daily, due to the provision of campaign datasets (2012, 2013, 2014) by several projects. Every scientist is invited to browse the catalog, complete the online registration form and use MISTRALS data. Feel free to contact mistrals-contact@sedoo.fr for any question.

  15. The MISTRALS programme data portal

    NASA Astrophysics Data System (ADS)

    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

    NASA Astrophysics Data System (ADS)

    Brissebrat, Guillaume; Albert-Aguilar, Alexandre; Belmahfoud, Nizar; Cloché, Sophie; Darras, Sabine; Descloitres, Jacques; Ferré, Hélène; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Labatut, Laurent; Petit de la Villéon, Loïc; Ramage, Karim; Schmechtig, Catherine; Vermeulen, Anne

    2016-04-01

    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. Data sets managed by different data centres (ICARE, IPSL, SEDOO, CORIOLIS) are available through interoperability protocols (OPeNDAP, xml requests...) or archive synchronisation. Every in situ data set is available in the native format, but the most commonly used data sets have been homogenized (property names, units, quality flags...) and inserted in a relational database, in order to enable accurate data selection, and download of different data sets in a shared format. At present the MISTRALS data portal enables to access about 600 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 form and use MISTRALS data. Feel free to contact mistrals-contact@sedoo.fr for any question.

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

    PubMed

    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.

  18. Health literacy and patient web portals.

    PubMed

    Coughlin, Steven S; Stewart, Jessica L; Young, Lufei; Heboyan, Vahé; De Leo, Gianluca

    2018-05-01

    There is limited evidence about the association between health literacy and use of patient web portals in patients with chronic illnesses. The objective of this review was to learn more about health literacy and use of patient web portals. Bibliographic searches were conducted in PubMed and CINAHL using relevant MeSH search terms and Boolean algebra commands. Qualitative studies and studies with a cross-sectional, cohort, or pre-/post-test design have shown that persons with limited health literacy are less likely to use patient web portals, although there is inconsistency in the association across studies. The conflicting findings may be partially due to racial and ethnic differences in health literacy or level of comfort in sharing private health information using mobile technologies. Several opportunities exist to improve the usability and acceptability of web portals for patients with limited health literacy including enhancements in the design of the portals, patient and provider education and training, and engagement of proxies such as caregivers and close family members. Copyright © 2018 Elsevier B.V. All rights reserved.

  19. Metabolic effects of portal vein sensing.

    PubMed

    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.

  20. Implications of Patient Portal Transparency in Oncology: Qualitative Interview Study on the Experiences of Patients, Oncologists, and Medical Informaticists

    PubMed Central

    2018-01-01

    Background Providing patients with unrestricted access to their electronic medical records through patient portals has impacted patient-provider communication and patients’ personal health knowledge. However, little is known about how patient portals are used in oncology. Objective The aim of this study was to understand attitudes of the portal’s adoption for oncology and to identify the advantages and disadvantages of using the portal to communicate and view medical information. Methods In-depth semistructured interviews were conducted with 60 participants: 35 patients, 13 oncologists, and 12 medical informaticists. Interviews were recorded, transcribed, and thematically analyzed to identify critical incidents and general attitudes encountered by participants. Results Two primary themes were discovered: (1) implementation practices influence attitudes, in which the decision-making and execution process of introducing portals throughout the hospital did not include the input of oncologists. Lack of oncologists’ involvement led to a lack of knowledge about portal functionality, such as not knowing the time period when test results would be disclosed to patients; (2) perceptions of portals as communication tools varies by user type, meaning that each participant group (patients, oncologists, and medical informaticists) had varied opinions about how the portal should be used to transmit and receive information. Oncologists and medical informaticists had difficulty understanding one another’s culture and communication processes in their fields, while patients had preferences for how they would like to receive communication, but it largely depended upon the type of test being disclosed. Conclusions The majority of patients (54%, 19/35) who participated in this study viewed lab results or scan reports via the portal before being contacted by a clinician. Most were relatively comfortable with this manner of disclosure but still preferred face-to-face or telephone

  1. Building a Smart Portal for Astronomy

    NASA Astrophysics Data System (ADS)

    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.

  2. Best Practices for Building Web Data Portals

    NASA Astrophysics Data System (ADS)

    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

  3. ERNIE performance with TSA portals Initial Results

    SciTech Connect

    Labov, S.

    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 analysismore » can improve analysis of measurements with the VM250 RPMs.« less

  4. The hospital library and the enterprise portal.

    PubMed

    Bandy, Margaret; Fosmire, Brenda

    2004-01-01

    At Exempla Healthcare, the medical librarians and the e-Business staff are creating an enterprise information portal where medical reference is targeted, easily accessible, and supported by the medical librarians. A team approach has been essential. The e-Business department has worked for nine months coordinating technical challenges required to support personalization, targeted communications, and a single access point for clinical patient data. Exempla medical librarians have been involved in the definition and design of information access needs from the very beginning. The Clinicians Portal was the first developed, with other customizations to follow. Many challenges remain, but by definition, a portal is designed to be flexible and adapt to the changing needs of the enterprise it supports.

  5. [The EU Portal: Implementation, importance, and features].

    PubMed

    von Aschen, Harald; Krafft, Hartmut

    2017-08-01

    The European Medicines Agency (EMA) is developing a web-based EU portal with a database "at Union level as a single entry point for the submission of data and information relating to clinical trials in accordance with" the new EU regulation No. 536/2014. The specifications are mostly published, but some documents are still missing. Because the project is integrated and has dependencies on other projects, this could result in other specification upgrades. The IT solution is under ongoing development until project completion in quarter III of 2019. The EU Portal and the database will be audited. If the audit is successful, the new regulation will come into force in October 2018. The use of the EU Portal will then be mandatory with some transition rules. The software development of the portal is restricted to the regulation and the derived requirements. It is not possible to implement any national requirements. We describe in this paper the current key functionalities of the portal and try to derive requirements for a national IT system.On 16.06.2017 the EMA Management Board announced that the development of the new portal has been delayed and it is foreseen that the new regulation can come into effect in 2019 at the earliest. The press release can be found here: http://www.ema.europa.eu/ema/index.jsp?curl=pages/news_and_events/news/2017/06/news_detail_002764.jsp%26mid=WC0b01ac058004d5c1 (accessed: 12.07.2017).

  6. Management of Portal Hypertension After Liver Transplantation.

    PubMed

    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 < .05), their splenic volume decreased markedly. After the interventions, only one case of recurrent variceal bleeding was reported. The calculated Doppler parameters were altered in the opposite direction in cases of pre-hepatic versus intra- or post-hepatic 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.

  7. Infection as a Trigger for Portal Hypertension.

    PubMed

    Steib, Christian J; Schewe, Julia; Gerbes, Alexander L

    2015-01-01

    Microbial infections are a relevant problem for patients with liver cirrhosis. Different types of bacteria are responsible for different kinds of infections: Escherichia coli and Klebsiella pneumoniae are frequently observed in spontaneous bacterial peritonitis or urinary tract infections, and Streptococcus pneumoniae and Mycoplasma pneumoniae in pulmonary infections. Mortality is up to 4-fold higher in infected patients with liver cirrhosis than in patients without infections. Key Messages: Infections in patients with liver cirrhosis are due to three major reasons: bacterial translocation, immune deficiency and an increased incidence of systemic infections. Nonparenchymal liver cells like Kupffer cells, sinusoidal endothelial cells and hepatic stellate cells are the first liver cells to come into contact with microbial products when systemic infection or bacterial translocation occurs. Kupffer cell (KC) activation by Toll-like receptor (TLR) agonists and endothelial sinusoidal dysfunction have been shown to be important mechanisms increasing portal pressure following intraperitoneal lipopolysaccharide pretreatment in cirrhotic rat livers. Reduced intrahepatic vasodilation and increased intrahepatic vasoconstriction are the relevant pathophysiological pathways. Thromboxane A2 and leukotriene (LT) C4/D4 have been identified as important vasoconstrictors. Accordingly, treatment with montelukast to inhibit the cysteinyl-LT1 receptor reduced portal pressure in cirrhotic rat livers. Clinical studies have demonstrated that activation of KCs, estimated by the amount of soluble CD163 in the blood, correlates with the risk for variceal bleeding. Additionally, intestinal decontamination with rifaximin in patients with alcohol-associated liver cirrhosis reduced the portal pressure and the risk for variceal bleeding. TLR activation of nonparenchymal liver cells by pathogens results in portal hypertension. This might explain the pathophysiologic correlation between microbial

  8. Framework Development Supporting the Safety Portal

    SciTech Connect

    Prescott, Steven Ralph; Kvarfordt, Kellie Jean; Vang, Leng

    2015-07-01

    In a collaborating scientific research arena it is important to have an environment where analysts have access to a shared repository of information, documents, and software tools, and be able to accurately maintain and track historical changes in models. The new Safety Portal cloud-based environment will be accessible remotely from anywhere regardless of computing platforms given that the platform has available Internet access and proper browser capabilities. Information stored at this environment would be restricted based on user assigned credentials. This report discusses current development of a cloud-based web portal for PRA tools.

  9. R2 Water Quality Portal Monitoring Stations

    EPA Pesticide Factsheets

    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).

  10. High performance a-Si solar cells and new fabrication methods for a-Si solar cells

    NASA Astrophysics Data System (ADS)

    Nakano, S.; Kuwano, Y.; Ohnishi, M.

    1986-12-01

    The super chamber, a separated UHV reaction-chamber system has been developed. A conversion efficiency of 11.7% was obtained for an a-Si solar cell using a high-quality i-layer deposited by the super chamber, and a p-layer fabricated by a photo-CVD method. As a new material, amorphous superlattice-structure films were fabricated by the photo-CVD method for the first time. Superlattice structure p-layer a-Si solar cells were fabricated, and a conversion efficiency of 10.5% was obtained. For the fabrication of integrated type a-Si solar cell modules, a laser pattering method was investigated. A thermal analysis of the multilayer structure was done. It was confirmed that selective scribing for a-Si, TCO and metal film is possible by controlling the laser power density. Recently developed a-Si solar power generation systems and a-Si solar cell roofing tiles are also described.

  11. Reasons and barriers for using a patient portal: survey among patients with diabetes mellitus.

    PubMed

    Ronda, Maaike C M; Dijkhorst-Oei, Lioe-Ting; Rutten, Guy E H M

    2014-11-25

    The use of a Web portal for patients with diabetes mellitus to access their own personal health record may result in improved diabetes outcomes. However, the adoption by patients is slow. This may be caused by patient characteristics, but also by the content, layout, and promotion of the portal. Detailed knowledge about this could help increase patients' participation in Web portals. The aim was to study the opinions of patients with diabetes and identify perceived barriers to using a Web portal to optimize its use. We conducted a survey among patients with type 1 and type 2 diabetes mellitus from 62 primary care practices and 1 outpatient hospital clinic in the central area of the Netherlands who all used the same electronic health record with a Web portal. Questionnaires about patient characteristics, opinions about reasons for use or nonuse, and about portal content were sent to 1500 patients with a login and 3000 patients without a login to the Web portal. Patient groups were stratified according to login frequency. Demographic and diabetes-related variables were analyzed with multivariable regression analysis. The total response rate was 66.63% (2391/4399); 1390 of 4399 patients (31.60%) were eligible for analysis. There were 413 regular users (login frequency more than once) and 758 nonusers (no login). Most nonusers (72.4%) stated that the main reason for not requesting a login was that they were unaware of the existence of the portal. Other barriers reported by patients were disinterest in managing their own disease (28.5%, 216/758) and feelings of inadequacy with the use of computers and Internet (11.6%, 88/758). Patients treated by a general practitioner were more frequently nonusers compared to patients treated by an internist (78.8%, 666/846 vs 28.3%, 92/325; P<.001) and more users than nonusers became aware of the Web portal through their physician (94.9%, 392/413 vs 48.8%, 102/209; P<.001). Nonusers perceived specific portal content as not as useful

  12. Reasons and Barriers for Using a Patient Portal: Survey Among Patients With Diabetes Mellitus

    PubMed Central

    Dijkhorst-Oei, Lioe-Ting; Rutten, Guy EHM

    2014-01-01

    Background The use of a Web portal for patients with diabetes mellitus to access their own personal health record may result in improved diabetes outcomes. However, the adoption by patients is slow. This may be caused by patient characteristics, but also by the content, layout, and promotion of the portal. Detailed knowledge about this could help increase patients’ participation in Web portals. Objective The aim was to study the opinions of patients with diabetes and identify perceived barriers to using a Web portal to optimize its use. Methods We conducted a survey among patients with type 1 and type 2 diabetes mellitus from 62 primary care practices and 1 outpatient hospital clinic in the central area of the Netherlands who all used the same electronic health record with a Web portal. Questionnaires about patient characteristics, opinions about reasons for use or nonuse, and about portal content were sent to 1500 patients with a login and 3000 patients without a login to the Web portal. Patient groups were stratified according to login frequency. Demographic and diabetes-related variables were analyzed with multivariable regression analysis. Results The total response rate was 66.63% (2391/4399); 1390 of 4399 patients (31.60%) were eligible for analysis. There were 413 regular users (login frequency more than once) and 758 nonusers (no login). Most nonusers (72.4%) stated that the main reason for not requesting a login was that they were unaware of the existence of the portal. Other barriers reported by patients were disinterest in managing their own disease (28.5%, 216/758) and feelings of inadequacy with the use of computers and Internet (11.6%, 88/758). Patients treated by a general practitioner were more frequently nonusers compared to patients treated by an internist (78.8%, 666/846 vs 28.3%, 92/325; P<.001) and more users than nonusers became aware of the Web portal through their physician (94.9%, 392/413 vs 48.8%, 102/209; P<.001). Nonusers perceived

  13. The Association of Patient Factors, Digital Access, and Online Behavior on Sustained Patient Portal Use: A Prospective Cohort of Enrolled Users.

    PubMed

    Woods, Susan S; Forsberg, Christopher W; Schwartz, Erin C; Nazi, Kim M; Hibbard, Judith H; Houston, Thomas K; Gerrity, Martha

    2017-10-17

    As electronic health records and computerized workflows expand, there are unprecedented opportunities to digitally connect with patients using secure portals. To realize the value of patient portals, initial reach across populations will need to be demonstrated, as well as sustained usage over time. The study aim was to identify patient factors associated with short-term and long-term portal usage after patients registered to access all portal functions. We prospectively followed a cohort of patients at a large Department of Veterans Affairs (VA) health care facility who recently completed identity proofing to use the VA patient portal. Information collected at baseline encompassed patient factors potentially associated with portal usage, including: demographics, Internet access and use, health literacy, patient activation, and self-reported health conditions. The primary outcome was the frequency of portal log-ins during 6-month and 18-month time intervals after study enrollment. A total of 270 study participants were followed prospectively. Almost all participants (260/268, 97.0%) reported going online, typically at home (248/268, 92.5%). At 6 months, 84.1% (227/270) of participants had visited the portal, with some variation in usage across demographic and health-related subgroups. There were no significant differences in portal log-ins by age, gender, education, marital status, race/ethnicity, distance to a VA facility, or patient activation measure. Significantly higher portal usage was seen among participants using high-speed broadband at home, greater self-reported ability using the Internet, and routinely going online. By 18 months, 91% participants had logged in to the portal, and no significant associations were found between usage and demographics, health status, or patient activation. When examining portal activity between 6 and 18 months, patients who were infrequent or high portal users remained in those categories, respectively. Short-term and long

  14. The Association of Patient Factors, Digital Access, and Online Behavior on Sustained Patient Portal Use: A Prospective Cohort of Enrolled Users

    PubMed Central

    Nazi, Kim M; Hibbard, Judith H; Houston, Thomas K

    2017-01-01

    Background As electronic health records and computerized workflows expand, there are unprecedented opportunities to digitally connect with patients using secure portals. To realize the value of patient portals, initial reach across populations will need to be demonstrated, as well as sustained usage over time. Objective The study aim was to identify patient factors associated with short-term and long-term portal usage after patients registered to access all portal functions. Methods We prospectively followed a cohort of patients at a large Department of Veterans Affairs (VA) health care facility who recently completed identity proofing to use the VA patient portal. Information collected at baseline encompassed patient factors potentially associated with portal usage, including: demographics, Internet access and use, health literacy, patient activation, and self-reported health conditions. The primary outcome was the frequency of portal log-ins during 6-month and 18-month time intervals after study enrollment. Results A total of 270 study participants were followed prospectively. Almost all participants (260/268, 97.0%) reported going online, typically at home (248/268, 92.5%). At 6 months, 84.1% (227/270) of participants had visited the portal, with some variation in usage across demographic and health-related subgroups. There were no significant differences in portal log-ins by age, gender, education, marital status, race/ethnicity, distance to a VA facility, or patient activation measure. Significantly higher portal usage was seen among participants using high-speed broadband at home, greater self-reported ability using the Internet, and routinely going online. By 18 months, 91% participants had logged in to the portal, and no significant associations were found between usage and demographics, health status, or patient activation. When examining portal activity between 6 and 18 months, patients who were infrequent or high portal users remained in those categories

  15. Portal verification using the KODAK ACR 2000 RT storage phosphor plate system and EC films. A semiquantitative comparison.

    PubMed

    Geyer, Peter; Blank, Hilbert; Alheit, Horst

    2006-03-01

    The suitability of the storage phosphor plate system ACR 2000 RT (Eastman Kodak Corp., Rochester, MN, USA), that is destined for portal verification as well as for portal simulation imaging in radiotherapy, had to be proven by the comparison with a highly sensitive verification film. The comparison included portal verification images of different regions (head and neck, thorax, abdomen, and pelvis) irradiated with 6- and 15-MV photons and electrons. Each portal verification image was done at the storage screen and the EC film as well, using the EC-L cassettes (both: Eastman Kodak Corp., Rochester, MN, USA) for both systems. The soft-tissue and bony contrast and the brightness were evaluated and compared in a ranking of the two compared images. Different phantoms were irradiated to investigate the high- and low-contrast resolution. To account for quality assurance application, the short-time exposure of the unpacked and irradiated storage screen by green and red room lasers was also investigated. In general, the quality of the processed ACR images was slightly higher than that of the films, mostly due to cases of an insufficient exposure to the film. The storage screen was able to verify electron portals even for low electron energies with only minor photon contamination. The laser lines were sharply and clearly visible on the ACR images. The ACR system may replace the film without any noticeable decrease in image quality thereby reducing processing time and saving the costs of films and avoiding incorrect exposures.

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

    ERIC Educational Resources Information Center

    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…

  17. The Monash Portal: More Than Just a Virtual Gateway.

    ERIC Educational Resources Information Center

    Kennedy, David; Webster, Len; Benson, Robyn; James, Di; Bailey, Nathan

    The My Monash Portal (Portal) at Monash University (Australia) provides a virtual gateway to support student-centered flexible learning by coordinating several of the university's key resources to meet the needs of students and staff. The Portal is intended to help deliver innovative learning programs, foster opportunities to undertake research,…

  18. Advanced millimeter-wave security portal imaging techniques

    NASA Astrophysics Data System (ADS)

    Sheen, David M.; Bernacki, Bruce E.; McMakin, Douglas L.

    2012-03-01

    Millimeter-wave (mm-wave) imaging is rapidly gaining acceptance as a security tool to augment conventional metal detectors and baggage x-ray systems for passenger screening at airports and other secured facilities. This acceptance indicates that the technology has matured; however, many potential improvements can yet be realized. The authors have developed a number of techniques over the last several years including novel image reconstruction and display techniques, polarimetric imaging techniques, array switching schemes, and high-frequency high-bandwidth techniques. All of these may improve the performance of new systems; however, some of these techniques will increase the cost and complexity of the mm-wave security portal imaging systems. Reducing this cost may require the development of novel array designs. In particular, RF photonic methods may provide new solutions to the design and development of the sequentially switched linear mm-wave arrays that are the key element in the mm-wave portal imaging systems. Highfrequency, high-bandwidth designs are difficult to achieve with conventional mm-wave electronic devices, and RF photonic devices may be a practical alternative. In this paper, the mm-wave imaging techniques developed at PNNL are reviewed and the potential for implementing RF photonic mm-wave array designs is explored.

  19. An interactive portal to empower cancer survivors: a qualitative study on user expectations.

    PubMed

    Kuijpers, Wilma; Groen, Wim G; Loos, Romy; Oldenburg, Hester S A; Wouters, Michel W J M; Aaronson, Neil K; van Harten, Wim H

    2015-09-01

    Portals are increasingly used to improve patient empowerment, but are still uncommon in oncology. In this study, we explored cancer survivors' and health professionals' expectations of possible features of an interactive portal. We conducted three focus groups with breast cancer survivors (n = 21), two with lung cancer survivors (n = 14), and four with health professionals (n = 31). Drafts of possible features of an interactive portal were presented as static screenshots: survivorship care plan (SCP), access to electronic medical record (EMR), appointments, e-consultation, online patient community, patient reported outcomes (PROs) plus feedback, telemonitoring service, online rehabilitation program, and online psychosocial self-management program. This presentation was followed by an open discussion. Focus groups were audiotaped, transcribed verbatim, and data were analyzed using content analysis. Important themes included fulfillment of information needs, communication, motivation, quality of feedback, and supervision. Cancer survivors were primarily interested in features that could fulfill their information needs: SCP, access to their EMR, and an overview of appointments. Health professionals considered PROs and telemonitoring as most useful features, as these provide relevant information about survivors' health status. We recommend to minimally include these features in an interactive portal for cancer survivors. This is the first study that evaluated the expectations of cancer survivors and health professionals concerning an interactive portal. Both groups were positive about the introduction of such a portal, although their preferences for the various features differed. These findings reflect their unique perspective and emphasize the importance of involving multiple stakeholders in the actual design process.

  20. Library Collections - Naval Oceanography Portal

    Science.gov Websites

    are here: Home › USNO › James M. Gilliss Library › Library Collections USNO Logo USNO Navigation of the James M. Gilliss library include: recently cataloged books, electronic journals, publications

  1. Farbrication of diffractive optical elements on a Si chip by an imprint lithography using nonsymmetrical silicon mold

    NASA Astrophysics Data System (ADS)

    Hirai, Yoshihiko; Okano, Masato; Okuno, Takayuki; Toyota, Hiroshi; Yotsuya, Tsutomu; Kikuta, Hisao; Tanaka, Yoshio

    2001-11-01

    Fabrication of a fine diffractive optical element on a Si chip is demonstrated using imprint lithography. A chirped diffraction grating, which has modulated pitched pattern with curved cross section is fabricated by an electron beam lithography, where the exposure dose profile is automatically optimized by computer aided system. Using the resist pattern as an etching mask, anisotropic dry etching is performed to transfer the resist pattern profile to the Si chip. The etched Si substrate is used as a mold in the imprint lithography. The Si mold is pressed to a thin polymer (poly methyl methacrylate) on a Si chip. After releasing the mold, a fine diffractive optical pattern is successfully transferred to the thin polymer. This method is exceedingly useful for fabrication of integrated diffractive optical elements with electric circuits on a Si chip.

  2. Intercomprehension: A Portal to Teachers' Intercultural Sensitivity

    ERIC Educational Resources Information Center

    Pinho, Ana Sofia

    2015-01-01

    The development of opportunities for teachers' professional development in plurilingual and intercultural education is a key issue in language teacher education and "intercomprehension" (IC) can provide a potential portal for the development of teachers' intercultural sensitivity. Particularly relevant to this is the creation of powerful…

  3. An Empirical Investigation of Campus Portal Usage

    ERIC Educational Resources Information Center

    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…

  4. The Catalog as Portal to the Internet.

    ERIC Educational Resources Information Center

    Thomas, Sarah E.

    This paper examines the potential of the library catalog to serve as a portal to the Internet. The first section provides an overview of the development of the catalog, including the emergence of the union catalog, standardization of cataloging practice, MARC format, and the insufficiency of resources to catalog all the titles acquired by…

  5. ExPASy: SIB bioinformatics resource portal.

    PubMed

    Artimo, Panu; Jonnalagedda, Manohar; Arnold, Konstantin; Baratin, Delphine; Csardi, Gabor; de Castro, Edouard; Duvaud, Séverine; Flegel, Volker; Fortier, Arnaud; Gasteiger, Elisabeth; Grosdidier, Aurélien; Hernandez, Céline; Ioannidis, Vassilios; Kuznetsov, Dmitry; Liechti, Robin; Moretti, Sébastien; Mostaguir, Khaled; Redaschi, Nicole; Rossier, Grégoire; Xenarios, Ioannis; Stockinger, Heinz

    2012-07-01

    ExPASy (http://www.expasy.org) has worldwide reputation as one of the main bioinformatics resources for proteomics. It has now evolved, becoming an extensible and integrative portal accessing many scientific resources, databases and software tools in different areas of life sciences. Scientists can henceforth access seamlessly a wide range of resources in many different domains, such as proteomics, genomics, phylogeny/evolution, systems biology, population genetics, transcriptomics, etc. The individual resources (databases, web-based and downloadable software tools) are hosted in a 'decentralized' way by different groups of the SIB Swiss Institute of Bioinformatics and partner institutions. Specifically, a single web portal provides a common entry point to a wide range of resources developed and operated by different SIB groups and external institutions. The portal features a search function across 'selected' resources. Additionally, the availability and usage of resources are monitored. The portal is aimed for both expert users and people who are not familiar with a specific domain in life sciences. The new web interface provides, in particular, visual guidance for newcomers to ExPASy.

  6. Liver surgery in cirrhosis and portal hypertension.

    PubMed

    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.

  7. Liver surgery in cirrhosis and portal hypertension

    PubMed Central

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

    2016-01-01

    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. PMID:26973411

  8. [Evaluation and treatment of portal hypertension].

    PubMed

    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.

  9. Collaboration Portals for NASA's Airborne Field Campaigns

    NASA Astrophysics Data System (ADS)

    Conover, H.; Kulkarni, A.; Garrett, M.; Goodman, M.; Petersen, W. A.; Drewry, M.; Hardin, D. M.; He, M.

    2011-12-01

    The University of Alabama in Huntsville (UAH), in collaboration with the Global Hydrology Resource Center, a NASA Earth Science Data Center, has provided information management for a number of NASA Airborne Field campaigns, both hurricane science investigations and satellite instrument validation. Effective field campaign management requires communication and coordination tools, including utilities for personnel to upload and share flight plans, weather forecasts, a variety of mission reports, preliminary science data, and personal photos. Beginning with the Genesis and Rapid Intensification Processes (GRIP) hurricane field campaign in 2010, we have provided these capabilities via a Drupal-based collaboration portal. This portal was reused and modified for the Midlatitude Continental Convective Clouds Experiment (MC3E), part of the Global Precipitation Measurement mission ground validation program. An end goal of these development efforts is the creation of a Drupal profile for field campaign management. This presentation will discuss experiences with Drupal in developing and using these collaboration portals. Topics will include Drupal modules used, advantages and disadvantages of working with Drupal in this context, and how the science teams used the portals in comparison with other communication and collaboration tools.

  10. Measuring Problem Solving Skills in "Portal 2"

    ERIC Educational Resources Information Center

    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…

  11. Airport testing an explosives detection portal

    SciTech Connect

    Rhykerd, C.; Linker, K.; Hannum, D.

    1998-08-01

    At the direction of the US Congress, following the Pan Am 103 and TWA 800 crashes, the Federal Aviation Administration funded development of non-invasive techniques to screen airline passengers for explosives. Such an explosives detection portal, developed at Sandia National Laboratories, was field tested at the Albuquerque International airport in September 1997. During the 2-week field trial, 2,400 passengers were screened and 500 surveyed. Throughput, reliability, maintenance and sensitivity were studied. Follow-up testing at Sandia and at Idaho National Engineering and Environmental Laboratory was conducted. A passenger stands in the portal for five seconds while overhead fans blow air overmore » his body. Any explosive vapors or dislodged particles are collected in vents at the feet. Explosives are removed from the air in a preconcentrator and subsequently directed into an ion mobility spectrometer for detection. Throughput measured 300 passengers per hour. The non-invasive portal can detect subfingerprint levels of explosives residue on clothing. A survey of 500 passengers showed a 97% approval rating, with 99% stating that such portals, if effective, should be installed in airports to improve security. Results of the airport test, as well as operational issues, are discussed.« less

  12. Collaboration Portals for NASA's Airborne Field Campaigns

    NASA Technical Reports Server (NTRS)

    Conover, Helen; Kulkami, Ajinkya; Garrett, Michele; Goodman, Michael; Peterson, Walter Arthur; Drewry, Marilyn; Hardin, Danny M.; He, Matt

    2011-01-01

    The University of Alabama in Huntsville (UAH), in collaboration with the Global Hydrology Resource Center, a NASA Earth Science Data Center, has provided information management for a number of NASA Airborne Field campaigns, both hurricane science investigations and satellite instrument validation. Effective field campaign management requires communication and coordination tools, including utilities for personnel to upload and share flight plans, weather forecasts, a variety of mission reports, preliminary science data, and personal photos. Beginning with the Genesis and Rapid Intensification Processes (GRIP) hurricane field campaign in 2010, we have provided these capabilities via a Drupal-based collaboration portal. This portal was reused and modified for the Midlatitude Continental Convective Clouds Experiment (MC3E), part of the Global Precipitation Measurement mission ground validation program. An end goal of these development efforts is the creation of a Drupal profile for field campaign management. This presentation will discuss experiences with Drupal in developing and using these collaboration portals. Topics will include Drupal modules used, advantages and disadvantages of working with Drupal in this context, and how the science teams used the portals in comparison with other communication and collaboration tools.

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

    PubMed

    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 < 0.05). Low WSS area often occurred in the junction area of SV and SMV into the PV, in the area of the division of PV into left and right PV, and in the outer wall of the curving SV in the control group. In the cirrhotic patients with 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.

  14. Portal hypertension and hypersplenism in extrahepatic portal venous obstruction: Are they related?

    PubMed

    Kilambi, Ragini; Singh, Anand Narayan; Madhusudhan, Kumble Seetharama; Pal, Sujoy; Saxena, Renu; Shalimar; Dash, Nihar Ranjan; Sahni, Peush

    2018-06-23

    Portal hypertension (PHT) due to extrahepatic portal venous obstruction (EHPVO) is common in developing countries. Hypersplenism is a near-constant feature of EHPVO, but its significance, unlike in cirrhotics, is unknown. We aimed to study the relationship between hypersplenism and the severity of PHT in patients with EHPVO. This prospective study was done at a tertiary care center from January 2014 to August 2015. All patients with EHPVO who underwent a splenectomy and a shunt or devascularization were included. Data regarding clinical profile, preoperative parameters, and intraoperative details were recorded. The correlation was studied between hypersplenism and the intraoperatively measured portal pressures and markers of PHT. Of the 40 patients studied (mean [SD] age 22.4 [8.4] years), hematological hypersplenism was present in 39 (97.5%). The mean (SD) hemoglobin, total leukocyte counts (TLC), and platelet counts were 9.9 (2.4) g/dL, 2971 (1239) cells/mm 3 , and 66,400 (32047) cells/mm 3 , respectively. The mean (SD) sonographic spleen volume (SV), splenic weight, and intraoperative portal pressure were 1084.7 (553.9) cm 3 , 1088.7 (454.7) g, and 35.6 (5.1) mmHg, respectively. The TLC and platelet counts correlated inversely with the portal pressure. Additionally, the platelet counts correlated negatively with eradicated variceal status, SV, and weight; hemoglobin with SV and weight; and TLC with SV. Multivariate analysis showed the platelet counts were an independent predictor of portal pressures and platelet counts ≤ 53,500 cells/mm 3 indicated significantly high portal pressures. The platelet counts showed a significant inverse correlation with portal pressures in patients with EHPVO and may be used as surrogate markers of PHT. A platelet count ≤ 53,500 cells/mm 3 is predictive of significantly high pressures.

  15. Pathophysiology of Portal Hypertension and Its Clinical Links

    PubMed Central

    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

  16. A-Si Photoreceptors At The Threshold Of Industrial Application

    NASA Astrophysics Data System (ADS)

    Senske, W.; Marschall, N.

    1986-03-01

    A-Si has become an attractive alternative for conventional electrophotographic photoreceptors. A-Si photoreceptors have been prepared by other laboratories by plasma deposition with blocking and protection layers. These photoreceptors are highly photosensitive and show low fatigue. Using sputtering we have shown that this technique is capable of produc-ing films with high charge acceptance. The increase of the deposition rate is presently un-der intensive investigation. High rates can be achieved by a higher degree of silane decomposition or by magnetron sputtering together with a higher power level. Deposition rates of more than 20 pm/h have been obtained by both techniques.

  17. The Rules of Engagement: Perspectives on Secure Messaging From Experienced Ambulatory Patient Portal Users

    PubMed Central

    Schnierle, Jeanette; Florian, Hannah; Agarwal, Aradhna; Rundell, Kristen; McAlearney, Ann Scheck

    2017-01-01

    Background Patient portals have shown promise in engaging individuals in self-management of chronic conditions by allowing patients to input and track health information and exchange secure electronic messages with their providers. Past studies have identified patient barriers to portal use including usability issues, low health literacy, and concerns about loss of personal contact as well as provider concerns such as increased time spent responding to messages. However, to date, studies of both patient and provider perspectives on portal use have focused on the pre-implementation or initial implementation phases and do not consider how these issues may change as patients and providers gain greater experience with portals. Objective Our study examined the following research question: Within primary care offices with high rates of patient-portal use, what do experienced physician and patient users of the ambulatory portal perceive as the benefits and challenges of portal use in general and secure messaging in particular? Methods This qualitative study involved 42 interviews with experienced physician and patient users of an ambulatory patient portal, Epic’s MyChart. Participants were recruited from the Department of Family Medicine at a large Academic Medical Center (AMC) and included providers and their patients, who had been diagnosed with at least one chronic condition. A total of 29 patients and 13 primary care physicians participated in the interviews. All interviews were conducted by telephone and followed a semistructured interview guide. Interviews were transcribed verbatim to permit rigorous qualitative analysis. Both inductive and deductive methods were used to code and analyze the data iteratively, paying particular attention to themes involving secure messaging. Results Experienced portal users discussed several emergent themes related to a need for greater clarity on when and how to use the secure messaging feature. Patient concerns included worry

  18. High Temperature Capacitive Pressure Sensor Employing a SiC Based Ring Oscillator

    NASA Technical Reports Server (NTRS)

    Meredith, Roger D.; Neudeck, Philip G.; Ponchak, George E.; Beheim, Glenn M.; Scardelletti, Maximilian; Jordan, Jennifer L.; Chen, Liang-Yu; Spry, David J.; Krawowski, Michael J.; Hunter, Gary W.

    2011-01-01

    In an effort to develop harsh environment electronic and sensor technologies for aircraft engine safety and monitoring, we have used capacitive-based pressure sensors to shift the frequency of a SiC-electronics-based oscillator to produce a pressure-indicating signal that can be readily transmitted, e.g. wirelessly, to a receiver located in a more benign environment. Our efforts target 500 C, a temperature well above normal operating conditions of commercial circuits but within areas of interest in aerospace engines, deep mining applications and for future missions to the Venus atmosphere. This paper reports for the first time a ring oscillator circuit integrated with a capacitive pressure sensor, both operating at 500 C. This demonstration represents a significant step towards a wireless pressure sensor that can operate at 500 C and confirms the viability of 500 C electronic sensor systems.

  19. Patient Web Portals to Improve Diabetes Outcomes: A Systematic Review

    PubMed Central

    Mayberry, Lindsay Satterwhite; Mulvaney, Shelagh A.; Hess, Rachel

    2011-01-01

    Patient web portals (PWPs), defined as the integration of electronic medical records and patient health records, have been related to enhanced patient outcomes. A literature review was conducted to characterize the design and evaluation of PWPs to improve health care processes and outcomes in diabetes. A summary of 26 articles revealed the positive impact PWPs have on patient outcomes, patient-provider communication, disease management, and access to and patient satisfaction with health care. Innovative and useful approaches included the evaluation of specific components of the PWPs, assessing the impact of PWPs on mediators of health behaviors, such as patient distress, identification of barriers to use, and patient willingness to pay for access. Future research should focus on relevant processes that mediate patient and provider use, impact on health care utilization, and a patient-centered approach to the design and integration of educational opportunities afforded through PWPs. PMID:20890688

  20. Data Archive and Portal Thrust Area Strategy Report

    SciTech Connect

    Sivaraman, Chitra; Stephan, Eric G.; Macduff, Matt C.

    2014-09-01

    This report describes the Data Archive and Portal (DAP), a key capability of the U.S. Department of Energy's Atmosphere to Electron (A2e) initiative. The DAP Thrust Area Planning Group was organized to develop a plan for deploying this capability. Primarily, the report focuses on a distributed system--a DOE Wind Cloud--that functions as a repository for all A2e data. The Wind Cloud will be accessible via an open, easy-to-navigate user interface that facilitates community data access, interaction, and collaboration. DAP management will work with the community, industry, and international standards bodies to develop standards for wind data and to capture importantmore » characteristics of all data in the Wind Cloud.« less

  1. Patient web portals to improve diabetes outcomes: a systematic review.

    PubMed

    Osborn, Chandra Y; Mayberry, Lindsay Satterwhite; Mulvaney, Shelagh A; Hess, Rachel

    2010-12-01

    Patient web portals (PWPs), defined as the integration of electronic medical records and patient health records, have been related to enhanced patient outcomes. A literature review was conducted to characterize the design and evaluation of PWPs to improve health care processes and outcomes in diabetes. A summary of 26 articles revealed the positive impact PWPs have on patient outcomes, patient-provider communication, disease management, and access to and patient satisfaction with health care. Innovative and useful approaches included the evaluation of specific components of the PWPs, assessing the impact of PWPs on mediators of health behaviors, such as patient distress, identification of barriers to use, and patient willingness to pay for access. Future research should focus on relevant processes that mediate patient and provider use, impact on health care utilization, and a patient-centered approach to the design and integration of educational opportunities afforded through PWPs.

  2. Use of a web portal by adult patients with pre-diabetes and type 2 diabetes mellitus seen in a family medicine outpatient clinic.

    PubMed

    Coughlin, Steven S; Heboyan, Vahé; Young, Lufei; De Leo, Gianluca; Wilkins, Thad

    2018-05-01

    There has been increasing interest in the use of web portals by patients with type 2 diabetes mellitus (T2DM). Studies of web portal use by patients with pre-diabetes have not been reported. To plan studies of web portal use by adult clinic patients seen for pre-diabetes and T2DM at an academic medical center, we examined characteristics of those who had or had not registered for a web portal. Electronic records were reviewed to identify web portal registration by patients treated for pre-diabetes or T2DM by age, sex, race and ethnicity. A total of 866 patients with pre-diabetes and 2,376 patients with T2DM were seen in a family medicine outpatient clinic. About 41.5% of patients with pre-diabetes and 34.7% of those with T2DM had registered for the web portal. In logistic regression analysis, web portal registration among patients with T2DM was significantly associated with age 41-45 years, and with Hispanic ethnicity. Similar results were obtained for pre-diabetes except that the positive association with age 41-45 years and inverse association with Hispanic ethnicity were not statistically significant. Among patients with pre-diabetes or T2DM, Black men and Black women were less likely to have registered than their white counterparts. Patients who were aged 18-25 and >65 years were less likely to have registered for the web portal than those 26-65 years. Additional research is needed to identify portal design features that improve health outcomes for patients with pre-diabetes and T2DM and interventions that will increase use of patient portals by pre-diabetic and diabetic patients, especially among Black patients and older patients.

  3. DES Science Portal: Computing Photometric Redshifts

    SciTech Connect

    Gschwend, Julia

    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,more » 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

  4. Improving Diabetes Management With a Patient Portal: Qualitative Study of a Diabetes Self-Management Portal

    PubMed Central

    Dupak, Kourtney; Kuehner, Zachary; Leonard, Kevin; Lovrics, Emily; Picton, Peter; Seto, Emily; Cafazzo, Joe

    2012-01-01

    Background 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. Objective The objective of our study was to evaluate the experience of patients and providers using an online diabetes management portal for patients. Methods 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. Results 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. Conclusions 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

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

    PubMed

    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.

  6. Assessment of percutaneous transhepatic portal vein embolization with portal vein stenting for perihilar cholangiocarcinoma with severe portal vein stenosis.

    PubMed

    Hyodo, Ryota; Suzuki, Kojiro; Ebata, Tomoki; Komada, Tomohiro; Mori, Yoshine; Yokoyama, Yukihiro; Igami, Tsuyoshi; Sugawara, Gen; Naganawa, Shinji; Nagino, Masato

    2015-04-01

    The aim of the present study was to assess the clinical efficiency of portal vein (PV) stenting when performed with preoperative percutaneous transhepatic portal vein embolization (PTPVE) in patients with severe PV stenosis due to tumor invasion. Between 2007 and 2013, four consecutive patients (one male, three females; mean age, 52 years; age range, 25-73 years) with perihilar cholangiocarcinoma and PV stenosis underwent PTPVE and PV stenting. Patients were analyzed with regard to the procedure, hypertrophy of the future remnant liver (FRL), and plasma clearance rate of indocyanine green by the FRL (ICGK-F). Further, the %FRL volume increase in PTPVE was compared between the stenting group and the usual PTPVE group who have perihilar cholangiocarcinomas without PV stenosis. Preoperative PTPVE with PV stenting was successfully performed and portal flow to the FRL improved after stenting in all four patients. The %FRL volume increase was 18-60% (mean, 34%) in the stenting group and was 12-51% (mean, 21%) in the usual PTPVE group. The ICGK-F value after PTPVE exceeded 0.05 in all four patients. All patients achieved R0 resection. Preoperative PTPVE with PV stenting appears to be feasible in cases of severe PV tumor invasion and stenosis. This procedure may allow a broader indication for surgery. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  7. Characteristics of patient portals developed in the context of health information exchanges: early policy effects of incentives in the meaningful use program in the United States.

    PubMed

    Otte-Trojel, Terese; de Bont, Antoinette; van de Klundert, Joris; Rundall, Thomas G

    2014-11-21

    In 2014, the Centers for Medicare & Medicaid Services in the United States launched the second stage of its Electronic Health Record (EHR) Incentive Program, providing financial incentives to providers to meaningfully use their electronic health records to engage patients online. Patient portals are electronic means to engage patients by enabling secure access to personal medical records, communication with providers, various self-management tools, and administrative functionalities. Outcomes of patient portals have mainly been reported in large integrated health systems. This may now change as the EHR Incentive Program enables and supports the use of patient portals in other types of health systems. In this paper, we focus on Health Information Exchanges (HIE): entities that facilitate data exchange within networks of independent providers. In response to the EHR Incentive Program, some Health Information Exchanges in the United States are developing patient portals and offering them to their network of providers. Such patient portals hold high value for patients, especially in fragmented health system contexts, due to the portals' ability to integrate health information from an array of providers and give patients one access point to this information. Our aim was to report on the early effects of the EHR incentives on patient portal development by HIEs. Specifically, we describe the characteristics of these portals, identify factors affecting adoption by providers during the 2013-2014 time frame, and consider what may be the primary drivers of providers' adoption of patient portals in the future. We identified four HIEs that were developing patient portals as of spring 2014. We collected relevant documents and conducted interviews with six HIE leaders as well as two providers that were implementing the portals in their practices. We performed content analysis on these data to extract information pertinent to our study objectives. Our findings suggest that there

  8. Understanding patient portal use: implications for medication management.

    PubMed

    Osborn, Chandra Y; Mayberry, Lindsay Satterwhite; Wallston, Kenneth A; Johnson, Kevin B; Elasy, Tom A

    2013-07-03

    The Internet can be leveraged to provide disease management support, including medication adherence promotion that, when tailored, can effectively improve adherence to medications. The growing adoption of patient portals represents an opportunity to support medication management and adherence more broadly, but virtually no data exist about the real and potential impact of existing portals on these outcomes. We sought to (1) understand who uses an existing patient portal and reasons for use and nonuse, (2) understand how portal users are using a portal to manage their medications, and (3) explore participants' ideas for improving portal functionality for medication management and adherence support. A total of 75 adults with type 2 diabetes participated in a mixed-methods study involving focus groups, a survey, and a medical chart review. We used quantitative data to identify differences between portal users and nonusers, and to test the relationship between the frequency of portal use and glycemic control among users. We used qualitative methods to understand how and why participants use a portal and their ideas for improving its medication management functionality. Of the enrolled participants, 81% (61/75) attended a focus group and/or completed a survey; portal users were more likely than nonusers to participate in that capacity (Fisher exact test; P=.01). Users were also more likely than nonusers to be Caucasian/white (Fisher exact test; P<.001), have higher incomes (Fisher exact test; P=.005), and be privately insured (Fisher exact test; P<.001). Users also tended to have more education than nonusers (Mann-Whitney U; P=.05), although this relationship was not significant at P<.05. Among users, more frequent use of a portal was associated with better A1C (Spearman rho =-0.30; P=.02). Reasons for nonuse included not knowing about the portal (n=3), not having access to a computer (n=3), or having a family member serve as an online delegate (n=1). Users reported

  9. Culture differences in design of portal sites.

    PubMed

    Fang, Xiaowen; Rau, Pei-Luen Patrick

    2003-01-15

    Two experiments were carried out to examine the effects of cultural differences between the Chinese and the US people on the perceived usability and search performance of World Wide Web (WWW) portal sites. Chinese users in Taiwan and US users in Chicago were recruited to perform searching tasks on two versions of Yahoo! portal site: the standard Yahoo! and Yahoo! Chinese. The layout of Yahoo! Chinese is the same as the layout of Yahoo!, and categories on Yahoo! Chinese have been translated from its US counterpart. A special browser was programmed to record all the keystroke data and participants were asked to fill out a satisfaction questionnaire after finishing the tasks. Significant differences of satisfaction and steps to perform some tasks were found between the two groups. The experiment results also provided more detailed insights into the cultural differences between the Chinese and the US users.

  10. Sinusoidal portal hypertension in hepatic amyloidosis.

    PubMed Central

    Bion, E; Brenard, R; Pariente, E A; Lebrec, D; Degott, C; Maitre, F; Benhamou, J P

    1991-01-01

    Hepatic venous catheterisation and transvenous liver biopsy were performed in five patients with hepatic amyloidosis. In three patients, hepatic venous pressures were normal and histological examination of the liver biopsy specimen showed discrete and sparse perisinusoidal amyloid deposits. In the other two, however, the gradient between wedged and free hepatic venous pressures was increased (12 and 16 mmHg; normal 1-4 mmHg) and amyloid deposits were abundant and diffuse in the Disse's space. This study shows that portal hypertension in patients with hepatic amyloidosis is of the sinusoidal type and is related to the reduction of vascular space of hepatic sinusoids by massive perisinusoidal amyloid deposits. Furthermore, portal hypertension is associated with a poor prognosis in patients with hepatic amyloidosis. Images Figure 1 Figure 2 PMID:1864548

  11. Phase contrast portal imaging using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Umetani, K.; Kondoh, T.

    2014-07-01

    Microbeam radiation therapy is an experimental form of radiation treatment with great potential to improve the treatment of many types of cancer. We applied a synchrotron radiation phase contrast technique to portal imaging to improve targeting accuracy for microbeam radiation therapy in experiments using small animals. An X-ray imaging detector was installed 6.0 m downstream from an object to produce a high-contrast edge enhancement effect in propagation-based phase contrast imaging. Images of a mouse head sample were obtained using therapeutic white synchrotron radiation with a mean beam energy of 130 keV. Compared to conventional portal images, remarkably clear images of bones surrounding the cerebrum were acquired in an air environment for positioning brain lesions with respect to the skull structure without confusion with overlapping surface structures.

  12. NewProt - a protein engineering portal.

    PubMed

    Schwarte, Andreas; Genz, Maika; Skalden, Lilly; Nobili, Alberto; Vickers, Clare; Melse, Okke; Kuipers, Remko; Joosten, Henk-Jan; Stourac, Jan; Bendl, Jaroslav; Black, Jon; Haase, Peter; Baakman, Coos; Damborsky, Jiri; Bornscheuer, Uwe; Vriend, Gert; Venselaar, Hanka

    2017-06-01

    The NewProt protein engineering portal is a one-stop-shop for in silico protein engineering. It gives access to a large number of servers that compute a wide variety of protein structure characteristics supporting work on the modification of proteins through the introduction of (multiple) point mutations. The results can be inspected through multiple visualizers. The HOPE software is included to indicate mutations with possible undesired side effects. The Hotspot Wizard software is embedded for the design of mutations that modify a proteins' activity, specificity, or stability. The NewProt portal is freely accessible at http://newprot.cmbi.umcn.nl/ and http://newprot.fluidops.net/. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  13. Novel treatment options for portal hypertension

    PubMed Central

    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

  14. Spin-0± portal induced Dark Matter

    NASA Astrophysics Data System (ADS)

    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.

  15. Diavideos: a diabetes health video portal.

    PubMed

    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.

  16. State of the SOOS GCMD Portal

    NASA Technical Reports Server (NTRS)

    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.

  17. Management of portal hypertension in children

    PubMed Central

    Gugig, Roberto; Rosenthal, Philip

    2012-01-01

    Portal hypertension can be caused by a wide variety of conditions. It frequently presents with bleeding from esophageal varices. The approach to acute variceal hemorrhage in children is a stepwise progression from least invasive to most invasive. Management of acute variceal bleeding is straightforward. But data on primary prophylaxis and long term management prevention of recurrent variceal bleeding in children is scarce, therefore prospective multicenter trials are needed to establish best practices. PMID:22468080

  18. Web portal on environmental sciences "ATMOS''

    NASA Astrophysics Data System (ADS)

    Gordov, E. P.; Lykosov, V. N.; Fazliev, A. Z.

    2006-06-01

    The developed under INTAS grant web portal ATMOS (http://atmos.iao.ru and http://atmos.scert.ru) makes available to the international research community, environmental managers, and the interested public, a bilingual information source for the domain of Atmospheric Physics and Chemistry, and the related application domain of air quality assessment and management. It offers access to integrated thematic information, experimental data, analytical tools and models, case studies, and related information and educational resources compiled, structured, and edited by the partners into a coherent and consistent thematic information resource. While offering the usual components of a thematic site such as link collections, user group registration, discussion forum, news section etc., the site is distinguished by its scientific information services and tools: on-line models and analytical tools, and data collections and case studies together with tutorial material. The portal is organized as a set of interrelated scientific sites, which addressed basic branches of Atmospheric Sciences and Climate Modeling as well as the applied domains of Air Quality Assessment and Management, Modeling, and Environmental Impact Assessment. Each scientific site is open for external access information-computational system realized by means of Internet technologies. The main basic science topics are devoted to Atmospheric Chemistry, Atmospheric Spectroscopy and Radiation, Atmospheric Aerosols, Atmospheric Dynamics and Atmospheric Models, including climate models. The portal ATMOS reflects current tendency of Environmental Sciences transformation into exact (quantitative) sciences and is quite effective example of modern Information Technologies and Environmental Sciences integration. It makes the portal both an auxiliary instrument to support interdisciplinary projects of regional environment and extensive educational resource in this important domain.

  19. Impact of health portal enrollment with email reminders on adherence to clinic appointments: a pilot study.

    PubMed

    Horvath, Monica; Levy, Janet; L'Engle, Pete; Carlson, Boyd; Ahmad, Asif; Ferranti, Jeffrey

    2011-05-26

    Internet portal technologies that provide access to portions of electronic health records have the potential to revolutionize patients' involvement in their care. However, relatively few descriptions of the demographic characteristics of portal enrollees or of the effects of portal technology on quality outcomes exist. This study examined data from patients who attended one of seven Duke Medicine clinics and who were offered the option of enrolling in and using the Duke Medicine HealthView portal (HVP). The HVP allows patients to manage details of their appointment scheduling and provides automated email appointment reminders in addition to the telephone and mail reminders that all patients receive. Our objective was to test whether portal enrollment with an email reminder functionality is significantly related to decreases in rates of appointment "no-shows," which are known to impair clinic operational efficiency. Appointment activity during a 1-year period was examined for all patients attending one of seven Duke Medicine clinics. Patients were categorized as portal enrollees or as nonusers either by their status at time of appointment or at the end of the 1-year period. Demographic characteristics and no-show rates among these groups were compared. A binomial logistic regression model was constructed to measure the adjusted impact of HVP enrollment on no-show rates, given confounding factors. To demonstrate the effect of HVP use over time, monthly no-show rates were calculated for patient appointment keeping and contrasted between preportal and postportal deployment periods. Across seven clinics, 58,942 patients, 15.7% (9239/58,942) of whom were portal enrollees, scheduled 198,199 appointments with an overall no-show rate of 9.9% (19,668/198,199). We found that HVP enrollees were significantly more likely to be female, white, and privately insured compared with nonusers. Bivariate no-show rate differences between portal enrollment groups varied widely according

  20. Impact of Health Portal Enrollment With Email Reminders on Adherence to Clinic Appointments: A Pilot Study

    PubMed Central

    Levy, Janet; L'Engle, Pete; Carlson, Boyd; Ahmad, Asif; Ferranti, Jeffrey

    2011-01-01

    Background Internet portal technologies that provide access to portions of electronic health records have the potential to revolutionize patients’ involvement in their care. However, relatively few descriptions of the demographic characteristics of portal enrollees or of the effects of portal technology on quality outcomes exist. This study examined data from patients who attended one of seven Duke Medicine clinics and who were offered the option of enrolling in and using the Duke Medicine HealthView portal (HVP). The HVP allows patients to manage details of their appointment scheduling and provides automated email appointment reminders in addition to the telephone and mail reminders that all patients receive. Objective Our objective was to test whether portal enrollment with an email reminder functionality is significantly related to decreases in rates of appointment “no-shows,” which are known to impair clinic operational efficiency. Methods Appointment activity during a 1-year period was examined for all patients attending one of seven Duke Medicine clinics. Patients were categorized as portal enrollees or as nonusers either by their status at time of appointment or at the end of the 1-year period. Demographic characteristics and no-show rates among these groups were compared. A binomial logistic regression model was constructed to measure the adjusted impact of HVP enrollment on no-show rates, given confounding factors. To demonstrate the effect of HVP use over time, monthly no-show rates were calculated for patient appointment keeping and contrasted between preportal and postportal deployment periods. Results Across seven clinics, 58,942 patients, 15.7% (9239/58,942) of whom were portal enrollees, scheduled 198,199 appointments with an overall no-show rate of 9.9% (19,668/198,199). We found that HVP enrollees were significantly more likely to be female, white, and privately insured compared with nonusers. Bivariate no-show rate differences between portal

  1. [Portal hypertension. Evidence-based guide].

    PubMed

    Mercado, Miguel Angel; Orozco Zepeda, Héctor; Plata-Muñoz, Juan José

    2004-01-01

    Treatment of portal hypertension has evolved widely during the last decades. Advances in physiopathology have allowed better application of therapeutic options and also have permitted to know the natural history of varices and variceal bleeding, predicting which patients have a higher risk of bleeding. It also permits probability of designing patient treatment. According to liver function and subadjacent liver disease, it is possible to offer different alternatives within the three possible scenarios (primary prophylaxis, acute bleeding episode, and secondary prophylaxis). For primary prophylaxis, pharmacotherapy offers the best choice. Endoscopic banding is also growing in these scenarios and probably will be accepted in the near future. For the acute bleeding episode, endoscopic therapy (sclerosis and/or bands) and/or pharmacologic therapy (octreotide, terlipresin) represent best choice, considering TIPS as a rescue option. Surgery is not used routinely in this scenario in most centers. For secondary prophylaxis, pharmaco- and endoscopic therapy are first-line treatments, while TIPS and surgery as second-line treatments. TIPS is mainly used in patients on a waiting list for liver transplantation. Surgery offers good results for low-risk patients, with good liver function and with portal blood-flow preserving procedures (selective shunts, extensive devascularizations). Liver transplantation is recommended for patients with poor liver function because together with portal hypertension, it treats subadjacent liver disease.

  2. Surgical management of portal cavernoma cholangiopathy.

    PubMed

    Varma, Vibha; Behera, Arunanshu; Kaman, Leileshwar; Chattopadhyay, Somnath; Nundy, Samiran

    2014-02-01

    The majority of patients with portal cavernoma cholangiopathy (PCC) are asymptomatic, however some (5-38%) present with obstructive jaundice, cholangitis, or even biliary pain due to bile duct stones which form as a result of stasis. Most patients with extrahepatic portal venous obstruction (EHPVO) present with variceal bleeding and hypersplenism and these are the usual indications for surgery. Those who present with PCC may also need decompression of their portosystemic system to reverse the biliary obstruction. It is important to realize that though endoscopic drainage has been proposed as a non-surgical approach to the management of PCC it is successful in only certain specific situations like those with bile duct calculi, cholangitis, etc. A small proportion of such patients will continue to have biliary obstruction and these patients are thought to have a mechanical ischemic stricture. These patients will require a second stage procedure in the form of a bilioenteric bypass to reverse the symptoms related to PCC. In the absence of a shuntable vein splenectomy and devascularization may resolve the PCC in a subset of patients by decreasing the portal pressure.

  3. Interventional Radiologic Treatment for Idiopathic Portal Hypertension

    SciTech Connect

    Hirota, Shozo; Ichikawa, Satoshi; Matsumoto, Shinichi

    1999-07-15

    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: Inmore » 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.« less

  4. Design and implementation of a portal for the medical equipment market: MEDICOM.

    PubMed

    Palamas, S; Kalivas, D; Panou-Diamandi, O; Zeelenberg, C; van Nimwegen, C

    2001-01-01

    The MEDICOM (Medical Products Electronic Commerce) Portal provides the electronic means for medical-equipment manufacturers to communicate online with their customers while supporting the Purchasing Process and Post Market Surveillance. The Portal offers a powerful Internet-based search tool for finding medical products and manufacturers. Its main advantage is the fast, reliable and up-to-date retrieval of information while eliminating all unrelated content that a general-purpose search engine would retrieve. The Universal Medical Device Nomenclature System (UMDNS) registers all products. The Portal accepts end-user requests and generates a list of results containing text descriptions of devices, UMDNS attribute values, and links to manufacturer Web pages and online catalogues for access to more-detailed information. Device short descriptions are provided by the corresponding manufacturer. The Portal offers technical support for integration of the manufacturers Web sites with itself. The network of the Portal and the connected manufacturers sites is called the MEDICOM system. To establish an environment hosting all the interactions of consumers (health care organizations and professionals) and providers (manufacturers, distributors, and resellers of medical devices). The Portal provides the end-user interface, implements system management, and supports database compatibility. The Portal hosts information about the whole MEDICOM system (Common Database) and summarized descriptions of medical devices (Short Description Database); the manufacturers servers present extended descriptions. The Portal provides end-user profiling and registration, an efficient product-searching mechanism, bulletin boards, links to on-line libraries and standards, on-line information for the MEDICOM system, and special messages or advertisements from manufacturers. Platform independence and interoperability characterize the system design. Relational Database Management Systems are used for

  5. Design and Implementation of a Portal for the Medical Equipment Market: MEDICOM

    PubMed Central

    Kalivas, Dimitris; Panou-Diamandi, Ourania; Zeelenberg, Cees; van Nimwegen, Chris

    2001-01-01

    Background The MEDICOM (Medical Products Electronic Commerce) Portal provides the electronic means for medical-equipment manufacturers to communicate online with their customers while supporting the Purchasing Process and Post Market Surveillance. The Portal offers a powerful Internet-based search tool for finding medical products and manufacturers. Its main advantage is the fast, reliable and up-to-date retrieval of information while eliminating all unrelated content that a general-purpose search engine would retrieve. The Universal Medical Device Nomenclature System (UMDNS) registers all products. The Portal accepts end-user requests and generates a list of results containing text descriptions of devices, UMDNS attribute values, and links to manufacturer Web pages and online catalogues for access to more-detailed information. Device short descriptions are provided by the corresponding manufacturer. The Portal offers technical support for integration of the manufacturers' Web sites with itself. The network of the Portal and the connected manufacturers' sites is called the MEDICOM system. Objective To establish an environment hosting all the interactions of consumers (health care organizations and professionals) and providers (manufacturers, distributors, and resellers of medical devices). Methods The Portal provides the end-user interface, implements system management, and supports database compatibility. The Portal hosts information about the whole MEDICOM system (Common Database) and summarized descriptions of medical devices (Short Description Database); the manufacturers' servers present extended descriptions. The Portal provides end-user profiling and registration, an efficient product-searching mechanism, bulletin boards, links to on-line libraries and standards, on-line information for the MEDICOM system, and special messages or advertisements from manufacturers. Platform independence and interoperability characterize the system design. Relational Database

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

    PubMed

    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

  7. EMODnet Physical Parameters (EMODNet PP) Portal

    NASA Astrophysics Data System (ADS)

    Novellino, A.; Schaap, D.; Manzella, G. M. R.; Pouliquen, S.; Gorringe, P.

    2012-04-01

    In December 2007 the European Parliament and Council adopted a common text for the Marine Strategy Framework Directive which aims to achieve environmentally healthy marine waters by 2020. This Directive includes an initiative for an overarching European Marine Observation and Data Network (EMODNet). During the one-year consultation phase that followed the release of the EU Green Paper on a Future Maritime Policy for the European Union, stakeholders gave an overwhelming positive response. Facilitating access to high quality marine data will resolve difficulties and stimulate an expansion of value-added public and commercial services, lay the foundations for sound governance and reduce uncertainties on human impact on the planet as well as of forecasts relating to the future state of the marine environment. Better and linked marine data will have an immediate impact on the planning of environmental policy and mitigation measures, and will also facilitate impact assessments and scientific work. The overall objectives of the EMODnet Physical Parameters (EMODNet PP) preparatory action is to provide access to archived and near real-time data on physical conditions in Europe's seas and oceans by means of a dedicated Pilot Portal and to determine how well the data meet the needs of users from industry, public authorities and scientists. The latter implicates that it is also an objective to identify data gaps and arguments why these gaps should be filled in future monitoring. This project will contribute towards the definition of an operational European Marine Observation and Data Network (EMODnet). This is done done by: 1. providing through a portal: a. access to marine data from measurement stations and ferryboxes. Both near real-time and archived data of time series are to be made available. b. metadata for these data sets using EMODnet/INSPIRE standards. c. metadata maps and overviews for whole sea-basins showing the availability of data and monitoring intensity of that

  8. Implementation of an Enterprise Information Portal (EIP) in the Loyola University Health System

    PubMed Central

    Price, Ronald N.; Hernandez, Kim

    2001-01-01

    Loyola University Chicago Stritch School of Medicine and Loyola University Medical Center have long histories in the development of applications to support the institutions' missions of education, research and clinical care. In late 1998, the institutions' application development group undertook an ambitious program to re-architecture more than 10 years of legacy application development (30+ core applications) into a unified World Wide Web (WWW) environment. The primary project objectives were to construct an environment that would support the rapid development of n-tier, web-based applications while providing standard methods for user authentication/validation, security/access control and definition of a user's organizational context. The project's efforts resulted in Loyola's Enterprise Information Portal (EIP), which meets the aforementioned objectives. This environment: 1) allows access to other vertical Intranet portals (e.g., electronic medical record, patient satisfaction information and faculty effort); 2) supports end-user desktop customization; and 3) provides a means for standardized application “look and feel.” The portal was constructed utilizing readily available hardware and software. Server hardware consists of multiprocessor (Intel Pentium 500Mhz) Compaq 6500 servers with one gigabyte of random access memory and 75 gigabytes of hard disk storage. Microsoft SQL Server was selected to house the portal's internal or security data structures. Netscape Enterprise Server was selected for the web server component of the environment and Allaire's ColdFusion was chosen for access and application tiers. Total costs for the portal environment was less than $40,000. User data storage is accomplished through two Microsoft SQL Servers and an existing SUN Microsystems enterprise server with eight processors, 750 gigabytes of disk storage operating Sybase relational database manager. Total storage capacity for all system exceeds one terabyte. In the past 12

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

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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 < 0.001). TIPS is a safe and efficacious treatment for symptomatic portal hypertension in HCC with PVTT.

  12. Disastrous Portal Vein Embolization Turned into a Successful Intervention

    SciTech Connect

    Dobrocky, Tomas, E-mail: tomas.dobrocky@insel.ch; Kettenbach, Joachim, E-mail: joachim.kettenbach@stpoelten.lknoe.at; Lopez-Benitez, Ruben, E-mail: Ruben.lopez@insel.ch

    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 balloonmore » catheter, inflating the balloon, and pulling the plug into the main right portal vein.« less

  13. ACTRIS Data Centre: An atmospheric data portal

    NASA Astrophysics Data System (ADS)

    Myhre, C. Lund; Fahre Vik, A.; Logna, R.; Torseth, K.; Linné, H.; O'Connor, E.

    2012-04-01

    ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure Network) is a European Project aiming at integrating European ground-based stations equipped with advanced instrumentation for studying aerosols, clouds, and short-lived gas-phase species. The ACTRIS activities result in improved atmospheric measurements data made at more than 60 European sites, from numerous instruments and includes variables measured by ground based in situ and remote sensing technologies. Core variables are in situ aerosol optical, physical and chemical properties, short-lived trace gases (volatile organic carbon and nitrogen oxides), aerosol scattering and extinction profiles, and cloud properties. The ACTRIS data centre (ACTRIS DC) is giving free and open access to all data resulting from the activities of the infrastructure network, complemented with data from other relevant networks and data bases. The overall goal is to facilitate scientists and other user groups access to atmospheric observational data, and to provide mature products for analysis and interpretation of atmospheric composition change. The ACTRIS DC aims at substantially increasing the number of high-quality data by providing long-term observational data relevant to climate and air quality research produced with standardized or comparable procedures throughout the network. The backbone of the ACTRIS DC is the three core data bases: - EARLINET Data Base hosting aerosol lidar data from more than 30 European sites - EBAS hosting ground based atmospheric in situ data from more than 1000 sites globally - Cloudnet hosting remote sensing cloud data and products from 5 European sites Furthermore, a joint portal is developed combining information from various data sources to gain new information not presently available from standalone databases or networks. The data centre will provide tools and services to facilitate the use of measurements for broad user communities. Higher level and integrated products will be

  14. OPTOELECTRONIC PROPERTIES AND THE GAP STATE DISTRIBUTION IN a-Si, Ge ALLOYS

    NASA Astrophysics Data System (ADS)

    Aljishi, S.; Smith, Z. E.; Wagner, S.

    In this article we review optical and electronic transport data measured in amorphous silicon-germanium alloys with the goal of identifying the density of states as a function of alloy composition. The results show that while alloying a-Si:H with germanium has little effect on the valence band tail, the conduction band tail density of states is increased dramatically. Defect distributions both above and below midgap are detected and identified with the dangling bond D+/° and D°/- states. The density of deep defects below midgap increases exponentially with germanium content. Above midgap, a large concentration of defects lying between 0.3 and 0.5 eV below the conduction band edge has a strong effect on transient electron transport.

  15. A two-dimensional matrix correction for off-axis portal dose prediction errors

    SciTech Connect

    Bailey, Daniel W.; Department of Radiation Medicine, Roswell Park Cancer Institute, Buffalo, New York 14263; Kumaraswamy, Lalith

    2013-05-15

    Purpose: This study presents a follow-up to a modified calibration procedure for portal dosimetry published by Bailey et al. ['An effective correction algorithm for off-axis portal dosimetry errors,' Med. Phys. 36, 4089-4094 (2009)]. A commercial portal dose prediction system exhibits disagreement of up to 15% (calibrated units) between measured and predicted images as off-axis distance increases. The previous modified calibration procedure accounts for these off-axis effects in most regions of the detecting surface, but is limited by the simplistic assumption of radial symmetry. Methods: We find that a two-dimensional (2D) matrix correction, applied to each calibrated image, accounts for off-axismore » prediction errors in all regions of the detecting surface, including those still problematic after the radial correction is performed. The correction matrix is calculated by quantitative comparison of predicted and measured images that span the entire detecting surface. The correction matrix was verified for dose-linearity, and its effectiveness was verified on a number of test fields. The 2D correction was employed to retrospectively examine 22 off-axis, asymmetric electronic-compensation breast fields, five intensity-modulated brain fields (moderate-high modulation) manipulated for far off-axis delivery, and 29 intensity-modulated clinical fields of varying complexity in the central portion of the detecting surface. Results: Employing the matrix correction to the off-axis test fields and clinical fields, predicted vs measured portal dose agreement improves by up to 15%, producing up to 10% better agreement than the radial correction in some areas of the detecting surface. Gamma evaluation analyses (3 mm, 3% global, 10% dose threshold) of predicted vs measured portal dose images demonstrate pass rate improvement of up to 75% with the matrix correction, producing pass rates that are up to 30% higher than those resulting from the radial correction technique alone

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

    PubMed Central

    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

    2017-01-01

    AIM To investigate wall shear stress (WSS) magnitude and distribution in cirrhotic patients with portal hypertension using computational fluid dynamics. METHODS 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. RESULTS For the idealized models, WSS in the portal hypertension group (0-10 dyn/cm2) was significantly lower than that in the healthy controls (10-20 dyn/cm2), and low WSS area (0-1 dyn/cm2) 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/cm2) was also significantly lower than that in the healthy controls (P < 0.05). Low WSS area often occurred in the junction area of SV and SMV into the PV, in the area of the division of PV into left and right PV, and in the outer wall of the curving SV in the control group. In the cirrhotic patients with 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. CONCLUSION 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. PMID:28566887

  17. Arachidonic acid metabolites and endothelial dysfunction of portal hypertension.

    PubMed

    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

  18. Development of the UTAUT2 model to measure the acceptance of medical laboratory portals by patients in Shiraz.

    PubMed

    Ravangard, Ramin; Kazemi, Zhila; Abbasali, Somaye Zaker; Sharifian, Roxana; Monem, Hossein

    2017-02-01

    One of the main stages for achieving the success is acceptance of technology by its users. Hence, identifying the effective factors in successful acceptance of information technology is necessary and vital. One such factor is usability. This study aimed to investigate the software usability in the "Unified Theory of Acceptance and Use of Technology 2 (UTAUT2)" model in patients' use of medical diagnosis laboratories' electronic portals in 2015. This cross-sectional study was carried out on 170 patients in 2015. A 27-item questionnaire adopted from previous research and the Usability Evaluation questionnaire were used for data collection. Data were analyzed using Structural Equation Modeling (SEM), with Partial Least Squares approach by SPSS 20.0 and Smart-PLS V3.0. The results showed that the construct of intention to use had significant associations with price value (t-value=2.77), hedonic motivation (t-value=4.46), habit (t-value=1.99) and usability (t-value=5.2), as well as the construct of usage behavior with usability (t-value=3.45) and intention to use (t-value=2.03). Considering the results of this study, the following recommendations can be made in order for the higher use of portals by the patients: informing patients about the advantages of using these portals, designing portals in a simple and understandable form, increasing the portals' attractiveness, etc.

  19. Gender Linked Metric Analysis of Portal Vein: A Sonographic Appraisal.

    PubMed

    Singh, Shikha; Pankaj, Arvind Kumar; Rani, Anita; Sharma, Pradeep Kumar; Chauhan, Puja

    2017-03-01

    Portal hypertension is one of the most mystifying and disconcerting abdominal ailment. Ultrasonography (USG) is an effective diagnostic tool for its prompt management. Knowledge of normal calibre of portal vein in a local setting is essential as literature reports contrasting values in different regions. It helps in early diagnosis of portal hypertension even before it is clinically manifested thereby assisting clinicians and interventional radiologists in pertinent management. Study was aimed to evaluate the Portal Vein Diameter (PVD) and find its correlation with gender by using USG in North Indian population. A total of 300 healthy adults were included in the study. Portal vein diameter was measured in supine position and normal respiration by grey scale USG. The portal vein diameter was correlated with age and gender statistically using independent Student's t-test and ANOVA. Mean PVD of (9.49±1.03 mm) was observed in the present cross-sectional study. Male showed a significantly higher mean PVD (9.70±1.02 mm) as compared to females (9.10±0.94 mm). Scarcity of information concerning ultrasonographically measured standard portal vein diameter and inconstant values reported in literature necessitates the need for establishing local standard value. In the given subset of population the portal vein diameter was influenced by the gender. The information will be helpful in prompt diagnosis and management of portal hypertension.

  20. Rational classification of portal vein thrombosis and its clinical significance.

    PubMed

    Ma, Jingqin; Yan, Zhiping; Luo, Jianjun; Liu, Qingxin; Wang, Jianhua; Qiu, Shijing

    2014-01-01

    Portal vein thrombosis (PVT) is commonly classified into acute (symptom duration <60 days and absence of portal carvernoma and portal hypertension) and chronic types. However, the rationality of this classification has received little attention. In this study, 60 patients (40 men and 20 women) with PVT were examined using contrast-enhanced computed tomography (CT). The percentage of vein occlusion, including portal vein (PV) and superior mesenteric vein (SMV), was measured on CT image. Of 60 patients, 17 (28.3%) met the criterion of acute PVT. Symptoms occurred more frequently in patients with superior mesenteric vein thrombosis (SMVT) compared to those without SMVT (p<0.001). However, there was no significant difference in PV occlusion between patients with and without symptoms. The frequency of cavernous transformation was significantly higher in patients with complete PVT than those with partial PVT (p<0.001). Complications of portal hypertension were significantly associated with cirrhosis (p<0.001) rather than with the severity of PVT and presence of cavernoma. These results suggest that the severity of PVT is only associated with the formation of portal cavernoma but unrelated to the onset of symptoms and the development of portal hypertension. We classified PVT into complete and partial types, and each was subclassified into with and without portal cavernoma. In conclusion, neither symptom duration nor cavernous transformation can clearly distinguish between acute and chronic PVT. The new classification system can determine the pathological alterations of PVT, patency of portal vein and outcome of treatment in a longitudinal study.

  1. Portal Vein Stenting for Delayed Jejunal Varix Bleeding Associated with Portal Venous Occlusion after Hepatobiliary and Pancreatic Surgery

    PubMed Central

    Hyun, Dongho; Cho, Sung Ki; Park, Hong Suk; Shin, Sung Wook; Choo, Sung Wook; Do, Young Soo; Choo, In Wook; Choi, Dong Wook

    2017-01-01

    Objective The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop. Materials and Methods 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. Results 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. Conclusion Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery. PMID:28860900

  2. A novel canine model of portal vein stenosis plus thioacetamide administration-induced cirrhotic portal hypertension with hypersplenism.

    PubMed

    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.

  3. Fabrication, characterization and testing of silicon photomultipliers for the Muon Portal Project

    NASA Astrophysics Data System (ADS)

    La Rocca, P.; Billotta, S.; Blancato, A. A.; Bonanno, D.; Bonanno, G.; Fallica, G.; Garozzo, S.; Lo Presti, D.; Marano, D.; Pugliatti, C.; Riggi, F.; Romeo, G.; Santagati, G.; Valvo, G.

    2015-07-01

    The Muon Portal is a recently started Project aiming at the construction of a large area tracking detector that exploits the muon tomography technique to inspect the contents of traveling cargo containers. The detection planes will be made of plastic scintillator strips with embedded wavelength-shifting fibres. Special designed silicon photomultipliers will read the scintillation light transported by the fibres along the strips and a dedicated electronics will combine signals from different strips to reduce the overall number of channels, without loss of information. Different silicon photomultiplier prototypes, both with the p-on-n and n-on-p technologies, have been produced by STMicroelectronics during the last years. In this paper we present the main characteristics of the silicon photomultipliers designed for the Muon Portal Project and describe the setup and the procedure implemented for the characterization of these devices, giving some statistical results obtained from the test of a first batch of silicon photomultipliers.

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

    PubMed

    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.

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

    PubMed

    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 < 0.001), the lateral antebrachial cutaneous nerve (4.0 mm, p < 0.001), and the radial nerve (25 mm, p < 0.001) was different from the average reported distances in the literature. A difference was found between the distance of the anterolateral portal and the PABCN (32 mm, p < 0.001) compared to previous studies. Three major iatrogenic complications were observed, including: laceration of the posterior bundle of the medial ulnar collateral ligament, lateral ulnar collateral ligament midsubstance laceration, and median nerve partial laceration. Surgeons increasingly consider arthroscopic treatment as an option for elbow pathology. In the present study a surgical complication rate of 30 % was found with novice portal placement during elbow arthroscopy. Furthermore, as the results from this study have indicated, accurate, precise, and safe portal placement in elbow arthroscopy is not easily achieved by didactic lecture and cadaver instruction session alone. Level of evidence V.

  6. Portal vein thrombosis in patients with cirrhosis

    PubMed Central

    von Köckritz, Leona; De Gottardi, Andrea; Praktiknjo, Michael

    2017-01-01

    Abstract Portal vein thrombosis (PVT) is frequent in patients with liver cirrhosis and possible severe complications such as mesenteric ischemia are rare, but can be life-threatening. However, different aspects of clinical relevance, diagnosis and management of PVT are still areas of uncertainty and investigation in international guidelines. In this article, we elaborate on PVT classification, geographical differences in clinical presentation and standards of diagnosis, and briefly on the current pathophysiological understanding and risk factors. This review considers and highlights the pitfalls of the various treatment approaches and prophylactic treatments. Finally, we review the controversial issue of clinical impact of PVT on prognosis, especially considering liver transplantation and future perspectives. PMID:28533912

  7. The Effect of Patient Portals on Quality Outcomes and Its Implications to Meaningful Use: A Systematic Review

    PubMed Central

    2015-01-01

    patient portal but instead analyzed features of a portal such as secure messaging, as well as disease management and monitoring. The ability of patients to be able to view their health information electronically meets the intent of Meaningful Use, Stage 2 requirements, but the ability to transmit to a third party was not found in the review. PMID:25669240

  8. The effect of patient portals on quality outcomes and its implications to meaningful use: a systematic review.

    PubMed

    Kruse, Clemens Scott; Bolton, Katy; Freriks, Greg

    2015-02-10

    The Health Information Technology for Economic and Clinical Health (HITECH) Act imposes pressure on health care organizations to qualify for "Meaningful Use". It is assumed that portals should increase patient participation in medical decisions, but whether or not the use of portals improves outcomes remains to be seen. The purpose of this systemic review is to outline and summarize study results on the effect of patient portals on quality, or chronic-condition outcomes as defined by the Agency for Healthcare Research and Quality, and its implications to Meaningful Use since the beginning of 2011. This review updates and builds on the work by Ammenwerth, Schnell-Inderst, and Hoerbst. We performed a systematic literature search in PubMed, CINAHL, and Google Scholar. We identified any data-driven study, quantitative or qualitative, that examined a relationship between patient portals, or patient portal features, and outcomes. We also wanted to relate the findings back to Meaningful Use criteria. Over 4000 articles were screened, and 27 were analyzed and summarized for this systematic review. We identified 26 studies and 1 review, and we summarized their findings and applicability to our research question. Very few studies associated use of the patient portal, or its features, to improved outcomes; 37% (10/27) of papers reported improvements in medication adherence, disease awareness, self-management of disease, a decrease of office visits, an increase in preventative medicine, and an increase in extended office visits, at the patient's request for additional information. The results also show an increase in quality in terms of patient satisfaction and customer retention, but there are weak results on medical outcomes. The results of this review demonstrate that more health care organizations today offer features of a patient portal than in the review published in 2011. Articles reviewed rarely analyzed a full patient portal but instead analyzed features of a portal

  9. Giant Intrahepatic Portal Vein Aneurysm: Leave it or Treat it?

    PubMed

    Shrivastava, Amit; Rampal, Jagdeesh S; Nageshwar Reddy, D

    2017-03-01

    Portal vein aneurysm (PVA) is a rare vascular dilatation of the portal vein. It is a rare vascular anomaly representing less than 3% of all visceral aneurysms and is not well understood. Usually, PVA are incidental findings, are asymptomatic, and clinical symptoms are proportionally related to size. Patients present with nonspecific epigastric pain or gastrointestinal bleeding with underlying portal hypertension. PVA may be associated with various complications such as biliary tract compression, portal vein thrombosis/rupture, duodenal compression, gastrointestinal bleeding, and inferior vena cava obstruction. Differential diagnoses of portal vein aneurysms are solid, cystic, and hypervascular abdominal masses, and it is important that the radiologists be aware of their multi-modality appearance; hence, the aim of this article was to provide an overview of the available literature to better simplify various aspects of this rare entity and diagnostic appearance on different modality with available treatment options. In our case, a 55-year-old male patient came to the gastroenterology OPD for further management of pancreatitis with portal hypertension and biliary obstruction with plastic stents in CBD and PD for the same. In this article, we have reported a case of largest intrahepatic portal vein aneurysm and its management by endovascular technique. As per our knowledge, this is the largest intrahepatic portal vein aneurysm and first case where the endovascular technique was used for the treatment of the same.

  10. A Community of Practice: Web Portals and Faculty Development.

    ERIC Educational Resources Information Center

    Carlson, Patricia A.

    2002-01-01

    Describes a Web portal constructed by Rose-Hulman Institute of Technology dedicated to improving middle school science, mathematics, and technology instruction. The portal emulates emerging corporate practices of knowledge management and process reinvention through information technology, and offers middle school teachers across Indiana a…

  11. Continued Use of a Chinese Online Portal: An Empirical Study

    ERIC Educational Resources Information Center

    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…

  12. Inflammation: a way to understanding the evolution of portal hypertension

    PubMed Central

    Aller, María-Angeles; Arias, Jorge-Luis; Cruz, Arturo; Arias, Jaime

    2007-01-01

    Background Portal hypertension is a clinical syndrome that manifests as ascites, portosystemic encephalopathy and variceal hemorrhage, and these alterations often lead to death. Hypothesis Splanchnic and/or systemic responses to portal hypertension could have pathophysiological mechanisms similar to those involved in the post-traumatic inflammatory response. The splanchnic and systemic impairments produced throughout the evolution of experimental prehepatic portal hypertension could be considered to have an inflammatory origin. In portal vein ligated rats, portal hypertensive enteropathy, hepatic steatosis and portal hypertensive encephalopathy show phenotypes during their development that can be considered inflammatory, such as: ischemia-reperfusion (vasodilatory response), infiltration by inflammatory cells (mast cells) and bacteria (intestinal translocation of endotoxins and bacteria) and lastly, angiogenesis. Similar inflammatory phenotypes, worsened by chronic liver disease (with anti-oxidant and anti-enzymatic ability reduction) characterize the evolution of portal hypertension and its complications (hepatorenal syndrome, ascites and esophageal variceal hemorrhage) in humans. Conclusion Low-grade inflammation, related to prehepatic portal hypertension, switches to high-grade inflammation with the development of severe and life-threatening complications when associated with chronic liver disease. PMID:17999758

  13. Endovascular management for significant iatrogenic portal vein bleeding.

    PubMed

    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.

  14. 8. FIGUEROA STREET TUNNEL NO. 2, SOUTH PORTAL SEEN FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. FIGUEROA STREET TUNNEL NO. 2, SOUTH PORTAL SEEN FROM ABOVE NORTH PORTAL OF TUNNEL NO. 3. LOOKING 12°N. - Figueroa Street Tunnels, Mileposts 24.90, 25.14, 25.28, & 25.37 on Arroyo Seco Parkway, Los Angeles, Los Angeles County, CA

  15. Teachers' Acceptance and Use of an Educational Portal

    ERIC Educational Resources Information Center

    Pynoo, Bram; Tondeur, Jo; van Braak, Johan; Duyck, Wouter; Sijnave, Bart; Duyck, Philippe

    2012-01-01

    In this study, teachers' acceptance and use of an educational portal is assessed based on data from two sources: usage data (number of logins, downloads, uploads, reactions and pages viewed) and an online acceptance questionnaire. The usage data is extracted on two occasions from the portal's database: at survey completion (T1) and twenty-two…

  16. 75 FR 24470 - Health Care Reform Insurance Web Portal Requirements

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-05

    ... Health Care Reform Insurance Web Portal Requirements AGENCY: Office of the Secretary, HHS. ACTION... Affordable Care Act) was enacted on March 23, 2010. It requires the establishment of an internet Web site (hereinafter referred to as a Web portal) through which individuals and small businesses can obtain information...

  17. An Analysis of Knowledge Management Mechanisms in Healthcare Portals

    ERIC Educational Resources Information Center

    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…

  18. Portal: Your Door to World Languages and Cultures

    ERIC Educational Resources Information Center

    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…

  19. Alaska Tidal Datum Portal | Alaska Division of Geological & Geophysical

    Science.gov Websites

    Engineering Geology Alaska Tidal Datum Portal Climate and Cryosphere Hazards Coastal Hazards Program Guide to Portal Unambiguous vertical datums in the coastal environment are critical to the evaluation of natural human life, property, and the coastal environment. January 2017 - Update Summary Alaska Tidal Datum

  20. Alaska Tidal Datum Portal - Alaska Tidal Datum Calculator | Alaska Division

    Science.gov Websites

    Coastal Hazards Program Guide to Geologic Hazards in Alaska MAPTEACH Tsunami Inundation Mapping Energy Portal main content Alaska Tidal Datum Portal Unambiguous vertical datums in the coastal environment are projects to ensure protection of human life, property, and the coastal environment. January 2017 - Update

  1. Pathology of idiopathic non-cirrhotic portal hypertension.

    PubMed

    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.

  2. 6. East portal of Tunnel 17, oblique view to westsouthwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. East portal of Tunnel 17, oblique view to west-southwest, 90mm lens. This view shows to advantage the stepped concrete wingwalls and fitted stone masonry coping protection flanking the portal, features typical of the Southern Pacific Common Standard tunnels of this period. - Southern Pacific Railroad Natron Cutoff, Tunnel No. 17, Milepost 408, Dorris, Siskiyou County, CA

  3. 2. West portal of Tunnel 18, oblique view to northnortheast, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 18, oblique view to north-northeast, 135mm lens. Note the use of concrete face and wingwalls, with dressed stone voussoirs, wingwall coping, parapet with stone belt course and coping, and coursed stone masonry slope protection flanking the portal. - Southern Pacific Railroad Natron Cutoff, Tunnel No. 18, Milepost 410, Dorris, Siskiyou County, CA

  4. 1. West portal of Tunnel 27 in distance, contextual view ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West portal of Tunnel 27 in distance, contextual view to northeast looking past Tunnel 26 (HAER CA-202) from atop east portal of Tunnel 25 (HAER CA-201), 380mm lens. - Central Pacific Transcontinental Railroad, Tunnel No. 27, Milepost 133.9, Applegate, Placer County, CA

  5. Intrahepatic portal hypertension secondary to metastatic carcinoma of the prostate.

    PubMed

    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.

  6. MedEdPORTAL: Educational Scholarship for Teaching

    ERIC Educational Resources Information Center

    Reynolds, Robby J.; Candler, Christopher S.

    2008-01-01

    MedEdPORTAL is an online publication service provided at no charge by the Association of American Medical Colleges (AAMC). The intent is to promote collaboration and educational scholarship by helping educators publish and share educational resources. With MedEdPORTAL, users can quickly locate high-quality, peer-reviewed teaching materials in both…

  7. The Anatomy of a Grid portal

    NASA Astrophysics Data System (ADS)

    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.

  8. Automatic indexing in a drug information portal.

    PubMed

    Sakji, Saoussen; Letord, Catherine; Dahamna, Badisse; Kergourlay, Ivan; Pereira, Suzanne; Joubert, Michel; Darmoni, Stéfan

    2009-01-01

    The objective of this work is to create a bilingual (French/English) Drug Information Portal (DIP), in a multi-terminological context and to emphasize its exploitation by an ATC automatic indexing allowing having more pertinent information about substances, organs or systems on which drugs act and their therapeutic and chemical characteristics. The development of the DIP was based on the CISMeF portal, which catalogues and indexes the most important and quality-controlled sources of institutional health information in French. DIP has created specific functionalities and uses specific drugs terminologies such as the ATC classification which used to automatic index the DIP resources. DIP is the result of collaboration between the CISMeF team and the VIDAL Company, specialized in drug information. DIP is conceived to facilitate the user information retrieval. The ATC automatic indexing provided relevant results in 76% of cases. Using multi-terminological context and in the framework of the drug field, indexing drugs with the appropriate codes or/and terms revealed to be very important to have the appropriate information storage and retrieval. The main challenge in the coming year is to increase the accuracy of the approach.

  9. Designing a data portal for synthesis modeling

    NASA Astrophysics Data System (ADS)

    Holmes, M. A.

    2006-12-01

    Processing of field and model data in multi-disciplinary integrated science studies is a vital part of synthesis modeling. Collection and storage techniques for field data vary greatly between the participating scientific disciplines due to the nature of the data being collected, whether it be in situ, remotely sensed, or recorded by automated data logging equipment. Spreadsheets, personal databases, text files and binary files are used in the initial storage and processing of the raw data. In order to be useful to scientists, engineers and modelers the data need to be stored in a format that is easily identifiable, accessible and transparent to a variety of computing environments. The Model Operations and Synthesis (MOAS) database and associated web portal were created to provide such capabilities. The industry standard relational database is comprised of spatial and temporal data tables, shape files and supporting metadata accessible over the network, through a menu driven web-based portal or spatially accessible through ArcSDE connections from the user's local GIS desktop software. A separate server provides public access to spatial data and model output in the form of attributed shape files through an ArcIMS web-based graphical user interface.

  10. Aquarium Portal Technique for PASTA Lesion Repair.

    PubMed

    Meyer, Dominik C; Gerber, Christian; Familiari, Filippo

    2017-10-01

    The simultaneous arthroscopic exposure of the subacromial and intra-articular space of the shoulder is challenging in the presence of only partial-thickness rotator cuff tears. We present our experience and method of entering the joint through the opened rotator cuff interval from an anterosuperior portal between the coracoid process and anterior acromion. With moderate (approximately 30°) abduction and external rotation, the rotator interval opens readily, offering a view with the camera toward the anterior edge of the supraspinatus tendon. An anterior view on the anterior leading edge of the supraspinatus tendon is obtained, showing the subacromial space above and the glenohumeral space below the tendon, similar to the view in an aquarium. The rotator cuff can be elevated using a rod inserted intra-articularly from posterior, whereas anchors and other instruments may be inserted from lateral. This approach offers the advantages of full exposure of the posterior undersurface of the rotator cuff insertion; a convenient approximately 90° angle between the camera and instruments; and no need to change portals for anchor placement, tendon stitching, or suture handling. The objective of this Technical Note is to describe our arthroscopic repair approach (aquarium technique) to PASTA (partial articular supraspinatus tendon avulsion) lesions.

  11. A web portal for hydrodynamical, cosmological simulations

    NASA Astrophysics Data System (ADS)

    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.

  12. Perturbative unitarity constraints on gauge portals

    NASA Astrophysics Data System (ADS)

    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.

  13. Perturbative unitarity constraints on gauge portals

    DOE PAGES

    El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

    2017-10-03

    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 andmore » 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. Here, we briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.« less

  14. Perturbative unitarity constraints on gauge portals

    SciTech Connect

    El Hedri, Sonia; Shepherd, William; Walker, Devin G. E.

    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 andmore » 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. Here, we briefly discuss the reach of future accelerator, direct and indirect detection experiments for this class of models.« less

  15. Indirect detection of neutrino portal dark matter

    NASA Astrophysics Data System (ADS)

    Batell, Brian; Han, Tao; Shams Es Haghi, Barmak

    2018-05-01

    We investigate the feasibility of the indirect detection of dark matter in a simple model using the neutrino portal. The model is very economical, with right-handed neutrinos generating neutrino masses through the type-I seesaw mechanism and simultaneously mediating interactions with dark matter. Given the small neutrino Yukawa couplings expected in a type-I seesaw, direct detection and accelerator probes of dark matter in this scenario are challenging. However, dark matter can efficiently annihilate to right-handed neutrinos, which then decay via active-sterile mixing through the weak interactions, leading to a variety of indirect astronomical signatures. We derive the existing constraints on this scenario from Planck cosmic microwave background measurements, Fermi dwarf spheroidal galaxy and Galactic center gamma-ray observations, and AMS-02 antiproton observations, and we also discuss the future prospects of Fermi and the Cherenkov Telescope Array. Thermal annihilation rates are already being probed for dark matter lighter than about 50 GeV, and this can be extended to dark matter masses of 100 GeV and beyond in the future. This scenario can also provide a dark matter interpretation of the Fermi Galactic center gamma-ray excess, and we confront this interpretation with other indirect constraints. Finally we discuss some of the exciting implications of extensions of the minimal model with large neutrino Yukawa couplings and Higgs portal couplings.

  16. Developing patient portals in a fragmented healthcare system.

    PubMed

    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

  17. The ADRICOSM STAR GeoPortal

    NASA Astrophysics Data System (ADS)

    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

  18. The SmartGeo Portal: A retrospective

    NASA Astrophysics Data System (ADS)

    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

  19. Stent Recanalization of Chronic Portal Vein Occlusion in a Child

    SciTech Connect

    Cwikiel, Wojciech; Solvig, Jan; Schroder, Henrik

    2000-07-15

    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. Themore » 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.« less

  20. Advances in the treatment of portal hypertension in cirrhosis.

    PubMed

    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.

  1. Advances in the management of childhood portal hypertension.

    PubMed

    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.

  2. Interface methods for using intranet portal organizational memory information system.

    PubMed

    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.

  3. Silicide phases formation in Co/c-Si and Co/a-Si systems during thermal annealing

    NASA Astrophysics Data System (ADS)

    Novaković, M.; Popović, M.; Zhang, K.; Lieb, K. P.; Bibić, N.

    2014-03-01

    The effect of the interface in cobalt-silicon bilayers on the silicide phase formation and microstructure has been investigated. Thin cobalt films were deposited by electron beam evaporation to a thickness of 50 nm on crystalline silicon (c-Si) or silicon with pre-amorphized surface (a-Si). After deposition one set of samples was annealed for 2 h at 200, 300, 400, 500, 600 and 700 °C. Another set of samples was irradiated with 400 keV Xe+ ions and then annealed at the same temperatures. Phase transitions were investigated with Rutherford backscattering spectroscopy, X-ray diffraction and cross-sectional transmission electron microscopy. No silicide formation was observed up to 400 °C, for both non-irradiated and ion-irradiated samples. When increasing the annealing temperature, the non-irradiated and irradiated Co/c-Si samples showed a similar behaviour: at 500 °C, CoSi appeared as the dominant silicide, followed by the formation of CoSi2 at 600 and 700 °C. In the case of non-irradiated Co/a-Si samples, no silicide formation occurred up to 700 °C, while irradiated samples with pre-amorphized substrate (Co/a-Si) showed a phase sequence similar to that in the Co/c-Si system. The observed phase transitions are found to be consistent with predictions of the effective heat of formation model.

  4. Extrahepatic Portal Vein Obstruction in Children: Role of Preoperative Imaging.

    PubMed

    Achar, Shashidhar; Dutta, Hemonta Kumar; Gogoi, Rudra Kanta

    2017-01-01

    Extrahepatic portal vein obstruction (EHPVO) is characterized by features of recent thrombosis or portal hypertension with portal cavernoma as a sequel of portal vein obstruction. Imaging of spleno-portal axis is the mainstay for the diagnosis of EHPVO. The aim of this study is to analyze the role of imaging in the preoperative assessment of the portal venous system in children with EHPVO. A hospital-based cross-sectional study was conducted on twenty children with EHPVO aged between 1 and 18 years over a period of 1 year. The children were evaluated clinically, followed by upper gastrointestinal endoscopy. Radiological assessment included imaging of the main portal vein, its right and left branches, splenic vein, and superior mesenteric vein using color Doppler ultrasonography (CDUSG) and magnetic resonance portovenogram (MRP). Evidence of portal biliopathy, status of collaterals, and possible sites for portosystemic shunt surgery were also examined. All the patients presented in chronic stage with portal cavernoma and only one patient (5%) had bland thrombus associated with cavernoma. The CDUSG and MRPs had a sensitivity of 66.6-90% and 96.7% and specificity of 91.5% and 98.3% respectively with regard to the assessment of the extent of thrombus formation and flow in the portal venous system. Both the modalities were found to be complementary to each other in preoperative assessment of EHPVO. However, the sensitivity of MRP was slightly superior to CDUSG in detecting occlusion and identifying portosystemic collaterals and dilated intrahepatic biliary radicals. Results of the present study indicate that MRP is well suited and superior to CDUSG in the preoperative imaging of patients with EHPVO.

  5. Splanchnic-aortic inflammatory axis in experimental portal hypertension

    PubMed Central

    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

  6. Organic Scintillation Detectors for Spectroscopic Radiation Portal Monitors

    NASA Astrophysics Data System (ADS)

    Paff, Marc Gerrit

    Thousands of radiation portal monitors have been deployed worldwide to detect and deter the smuggling of nuclear and radiological materials that could be used in nefarious acts. Radiation portal monitors are often installed at bottlenecks where large amounts of people or goods must traverse. Examples of use include scanning cargo containers at shipping ports, vehicles at border crossings, and people at high profile functions and events. Traditional radiation portal monitors contain separate detectors for passively measuring neutron and gamma ray count rates. 3He tubes embedded in polyethylene and slabs of plastic scintillators are the most common detector materials used in radiation portal monitors. The radiation portal monitor alarm mechanism relies on measuring radiation count rates above user defined alarm thresholds. These alarm thresholds are set above natural background count rates. Minimizing false alarms caused by natural background and maximizing sensitivity to weakly emitting threat sources must be balanced when setting these alarm thresholds. Current radiation portal monitor designs suffer from frequent nuisance radiation alarms. These radiation nuisance alarms are most frequently caused by shipments of large quantities of naturally occurring radioactive material containing cargo, like kitty litter, as well as by humans who have recently undergone a nuclear medicine procedure, particularly 99mTc treatments. Current radiation portal monitors typically lack spectroscopic capabilities, so nuisance alarms must be screened out in time-intensive secondary inspections with handheld radiation detectors. Radiation portal monitors using organic liquid scintillation detectors were designed, built, and tested. A number of algorithms were developed to perform on-the-fly radionuclide identification of single and combination radiation sources moving past the portal monitor at speeds up to 2.2 m/s. The portal monitor designs were tested extensively with a variety of

  7. 29 CFR 790.5 - Effect of Portal-to-Portal Act on determination of hours worked.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... the working face to the portal of the mine, the only time spent in such travel which the employer is required to count as hours worked will be the time spent in traveling from the portal to the working face... extent stated in section 4(d). This section requires that: . . . in determining the time for which an...

  8. Altered blood-brain barrier permeability in rats with prehepatic portal hypertension turns to normal when portal pressure is lowered

    PubMed Central

    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

  9. Barriers and Facilitators Affecting Patient Portal Implementation from an Organizational Perspective: Qualitative Study.

    PubMed Central

    Kooij, Laura; Groen, Wim G

    2018-01-01

    Background The number of patient portals is rising, and although portals can have positive effects, their implementation has major impacts on the providing health care institutions. However, little is known about the organizational factors affecting successful implementation. Knowledge of the specific barriers to and facilitators of various stakeholders is likely to be useful for future implementations. Objective The objective of this study was to identify the barriers to and facilitators of patient portal implementation facing various stakeholders within hospital organizations in the Netherlands. Methods Purposive sampling was used to select hospitals of various types. A total of 2 university medical centers, 3 teaching hospitals, and 2 general hospitals were included. For each, 3 stakeholders were interviewed: (1) medical professionals, (2) managers, and (3) information technology employees. In total, 21 semistructured interviews were conducted using the Grol and Wensing model, which describes barriers to and facilitators of change in health care practice at 6 levels: (1) innovation; (2) individual professional; (3) patient; (4) social context; (5) organizational context; and (6) economic and political context. Two researchers independently selected and coded quotes by applying this model using a (deductive) directed content approach. Additional factors related to technical and portal characteristics were added using the model of McGinn et al, developed for implementation of electronic health records. Results In total, we identified 376 quotes, 26 barriers, and 28 facilitators. Thirteen barriers and 12 facilitators were common for all stakeholder groups. The facilitators’ perceived usefulness (especially less paperwork) was mentioned by all the stakeholders, followed by subjects’ positive attitude. The main barriers were lack of resources (namely, lack of staff and materials), financial difficulties (especially complying with high costs, lack of

  10. Barriers and Facilitators Affecting Patient Portal Implementation from an Organizational Perspective: Qualitative Study.

    PubMed

    Kooij, Laura; Groen, Wim G; van Harten, Wim H

    2018-05-11

    The number of patient portals is rising, and although portals can have positive effects, their implementation has major impacts on the providing health care institutions. However, little is known about the organizational factors affecting successful implementation. Knowledge of the specific barriers to and facilitators of various stakeholders is likely to be useful for future implementations. The objective of this study was to identify the barriers to and facilitators of patient portal implementation facing various stakeholders within hospital organizations in the Netherlands. Purposive sampling was used to select hospitals of various types. A total of 2 university medical centers, 3 teaching hospitals, and 2 general hospitals were included. For each, 3 stakeholders were interviewed: (1) medical professionals, (2) managers, and (3) information technology employees. In total, 21 semistructured interviews were conducted using the Grol and Wensing model, which describes barriers to and facilitators of change in health care practice at 6 levels: (1) innovation; (2) individual professional; (3) patient; (4) social context; (5) organizational context; and (6) economic and political context. Two researchers independently selected and coded quotes by applying this model using a (deductive) directed content approach. Additional factors related to technical and portal characteristics were added using the model of McGinn et al, developed for implementation of electronic health records. In total, we identified 376 quotes, 26 barriers, and 28 facilitators. Thirteen barriers and 12 facilitators were common for all stakeholder groups. The facilitators' perceived usefulness (especially less paperwork) was mentioned by all the stakeholders, followed by subjects' positive attitude. The main barriers were lack of resources (namely, lack of staff and materials), financial difficulties (especially complying with high costs, lack of reimbursements), and guaranteeing privacy and security

  11. Patients, care partners, and shared access to the patient portal: online practices at an integrated health system.

    PubMed

    Wolff, Jennifer L; Berger, Andrea; Clarke, Deserae; Green, Jamie A; Stametz, Rebecca; Yule, Christina; Darer, Jonathan D

    2016-11-01

    To describe the characteristics and online practices of patients and "care partners" who share explicit access to a patient portal account at a large integrated health system that implemented shared access functionality in 2003. Survey of 323 patients and 389 care partners at Geisinger Health System with linked information regarding access and use of patient portal functionality. Few (0.4%) registered adult patient portal users shared access to their account. Patients varied in age (range: 18-102); more than half had a high school education or less (53.6%). Patient motivations for sharing access included: to help manage care (41.9%), for emergency reasons (29.7%), lack of technology experience (18.4%), or care partner request (10.0%). Care partners were parents (39.8%), adult children (27.9%), spouses (26.2%), and other relatives (6.1%). Patients were more likely than care partners to have inadequate health literacy (54.8% versus 8.8%, P < .001) and less confident in their ability to manage their care (53.0% versus 88.1%; P < .001). Care partners were more likely than patients to perform health management activities electronically (95.5% versus 48.4%; P < .001), access the patient portal (89.2% versus 30.3%; P < .001), and use patient portal functionality such as secure messaging (39.6% versus 13.9%; P < .001). Care partners used their own credentials (89.1%) and patient credentials (23.3%) to access the patient portal. Shared access is an underused strategy that may bridge patients' health literacy deficits and lack of technology experience and that helps but does not fully resolve concerns regarding patient and care partner identity credentials. © The Author 2016. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Electric measurements of PV heterojunction structures a-SiC/c-Si

    NASA Astrophysics Data System (ADS)

    Perný, Milan; Šály, Vladimír; Janíček, František; Mikolášek, Miroslav; Váry, Michal; Huran, Jozef

    2018-01-01

    Due to the particular advantages of amorphous silicon or its alloys with carbon in comparison to conventional crystalline materials makes such a material still interesting for study. The amorphous silicon carbide may be used in a number of micro-mechanical and micro-electronics applications and also for photovoltaic energy conversion devices. Boron doped thin layers of amorphous silicon carbide, presented in this paper, were prepared due to the optimization process for preparation of heterojunction solar cell structure. DC and AC measurement and subsequent evaluation were carried out in order to comprehensively assess the electrical transport processes in the prepared a-SiC/c-Si structures. We have investigated the influence of methane content in deposition gas mixture and different electrode configuration.

  13. Barriers to patient portal access among veterans receiving home-based primary care: a qualitative study.

    PubMed

    Mishuris, Rebecca G; Stewart, Max; Fix, Gemmae M; Marcello, Thomas; McInnes, D Keith; Hogan, Timothy P; Boardman, Judith B; Simon, Steven R

    2015-12-01

    Electronic, or web-based, patient portals can improve patient satisfaction, engagement and health outcomes and are becoming more prevalent with the advent of meaningful use incentives. However, adoption rates are low, particularly among vulnerable patient populations, such as those patients who are home-bound with multiple comorbidities. Little is known about how these patients view patient portals or their barriers to using them. To identify barriers to and facilitators of using My HealtheVet (MHV), the United States Department of Veterans Affairs (VA) patient portal, among Veterans using home-based primary care services. Qualitative study using in-depth semi-structured interviews. We conducted a content analysis informed by grounded theory. Fourteen Veterans receiving home-based primary care, surrogates of two of these Veterans, and three home-based primary care (HBPC) staff members. We identified five themes related to the use of MHV: limited knowledge; satisfaction with current HBPC care; limited computer and Internet access; desire to learn more about MHV and its potential use; and value of surrogates acting as intermediaries between Veterans and MHV. Despite their limited knowledge of MHV and computer access, home-bound Veterans are interested in accessing MHV and using it as an additional point of care. Surrogates are also potential users of MHV on behalf of these Veterans and may have different barriers to and benefits from use. © 2014 John Wiley & Sons Ltd.

  14. Reaching Prevention Professionals: The Mentor Portal Cost-Benefit Analysis of a Drug Misuse Prevention Portal

    DTIC Science & Technology

    2002-09-01

    starting point is the actual moment with a very low assumption of 1100 reached practitioners who actually perform internet research via the portal...Total 13.4 100% Research time saved hours a week 40 % of research time 29% % of research through internet 22% internet research time...in minutes 150.6 reduction in minutes 20 reduction in % of internet research time 13.3% reduction in % total time 0.8% Exchange

  15. The split portal: Description of a new accessory posterior portal for arthroscopic shoulder instability procedures.

    PubMed

    Mirouse, Guillaume; Nourissat, Geoffroy

    2016-02-01

    Open approach to the posterior shoulder during bone block for posterior shoulder instability is challenging. Anatomical study was performed to identify landmarks of a portal, avoiding soft tissue damage, between the infraspinatus (IS) and teres minor (TM) muscles and distant from the supra-scapular nerve (SSN) for arthroscopic shoulder bone block. Eight fresh-frozen cadaveric shoulder specimens were used. The arthroscope was introduced through the soft point (SP). A guide wire was placed through the SP, in the rotator interval direction. A posterior open dissection exposed the split between the IS and TM. A new guide wire was placed into the split, parallel to the first wire, to locate the new posterior arthroscopic approach. Ten distances were measured to define the safe position. The mean values were: SP to split IS-TM: 2 ± 0.2 (2-2.8); spinal bone to split IS-TM: 5 ± 0.5 (3-6.2); split IS-TM to posterior glenoid 6 o'clock: 1.3 ± 0.3 (0.6-1.6), 9 o'clock: 1.5 ± 0.3 (1-1.9), and 12 o'clock: 2 ± 0.1 (2.1-2.4); SSN to posterior glenoid 6 o'clock: 2.4 ± 0.2 (2.1-2.6), 9 o'clock: 1.7 ± 0.1 (1.5-1.8), and 12 o'clock: 1.5 ± 0.3 (1.2-2.1); and SSN to split IS-TM: 2 ± 0.3 (1.2-2.1). This preliminary anatomical study described a posterior arthroscopic portal located 2 cm under the SP, parallel to the SP portal direction, and finishing between 7 and 8 o'clock at the posterior rim of the glenoid. For arthroscopic shoulder bone block, this portal can avoid muscle and SSN lesions.

  16. NASA Sea Level Change Portal - It not just another portal site

    NASA Astrophysics Data System (ADS)

    Huang, T.; Quach, N.; Abercrombie, S. P.; Boening, C.; Brennan, H. P.; Gill, K. M.; Greguska, F. R., III; Jackson, R.; Larour, E. Y.; Shaftel, H.; Tenenbaum, L. F.; Zlotnicki, V.; Moore, B.; Moore, J.; Boeck, A.

    2017-12-01

    The NASA Sea Level Change Portal (https://sealevel.nasa.gov) is designed as a "one-stop" source for current sea level change information, including interactive tools for accessing and viewing regional data, a virtual dashboard of sea level indicators, and ongoing updates through a suite of editorial products that include content articles, graphics, videos, and animations. With increasing global temperatures warming the ocean and melting ice sheets and glaciers, there is an immediate need both for accelerating sea level change research and for making this research accessible to scientists in disparate discipline, to the general public, to policy makers and business. The immersive and innovative NASA portal debuted at the 2015 AGU attracts thousands of daily visitors and over 30K followers on Facebook®. Behind its intuitive interface is an extensible architecture that integrates site contents, data for various sources, visualization, horizontal-scale geospatial data analytic technology (called NEXUS), and an interactive 3D simulation platform (called the Virtual Earth System Laboratory). We will present an overview of our NASA portal and some of our architectural decisions along with discussion on our open-source, cloud-based data analytic technology that enables on-the-fly analysis of heterogeneous data.

  17. Statistical characterization of portal images and noise from portal imaging systems.

    PubMed

    González-López, Antonio; Morales-Sánchez, Juan; Verdú-Monedero, Rafael; Larrey-Ruiz, Jorge

    2013-06-01

    In this paper, we consider the statistical characteristics of the so-called portal images, which are acquired prior to the radiotherapy treatment, as well as the noise that present the portal imaging systems, in order to analyze whether the well-known noise and image features in other image modalities, such as natural image, can be found in the portal imaging modality. The study is carried out in the spatial image domain, in the Fourier domain, and finally in the wavelet domain. The probability density of the noise in the spatial image domain, the power spectral densities of the image and noise, and the marginal, joint, and conditional statistical distributions of the wavelet coefficients are estimated. Moreover, the statistical dependencies between noise and signal are investigated. The obtained results are compared with practical and useful references, like the characteristics of the natural image and the white noise. Finally, we discuss the implication of the results obtained in several noise reduction methods that operate in the wavelet domain.

  18. Superheavy dark matter through Higgs portal operators

    NASA Astrophysics Data System (ADS)

    Kolb, Edward W.; Long, Andrew J.

    2017-11-01

    The WIMPzilla hypothesis is that the dark matter is a super-weakly-interacting and superheavy particle. Conventionally, the WIMPzilla abundance is set by gravitational particle production during or at the end of inflation. In this study we allow the WIMPzilla to interact directly with Standard Model fields through the Higgs portal, and we calculate the thermal production (freeze-in) of WIMPzilla dark matter from the annihilation of Higgs boson pairs in the plasma. The two particle-physics model parameters are the WIMPzilla mass and the Higgs-WIMPzilla coupling. The two cosmological parameters are the reheating temperature and the expansion rate of the universe at the end of inflation. We delineate the regions of parameter space where either gravitational or thermal production is dominant, and within those regions we identify the parameters that predict the observed dark matter relic abundance. Allowing for thermal production opens up the parameter space, even for Planck-suppressed Higgs-WIMPzilla interactions.

  19. The BAOBAB data portal and DACCIWA database

    NASA Astrophysics Data System (ADS)

    Brissebrat, Guillaume; Belmahfoud, Nizar; Cloché, Sophie; Ferré, Hélène; Fleury, Laurence; Mière, Arnaud; Ramage, Karim

    2017-04-01

    In the framework of the African Monsoon Multidisciplinary Analyses (AMMA) programme, several tools have been developed in order to boost the data and information exchange between researchers from different disciplines: a user-friendly data management and dissemination system, quasi real-time display websites and a scientific paper exchange collaborative tool. The information system is enriched by past and ongoing projects (IMPETUS, FENNEC, ESCAPE, QweCI, ACASIS, DACCIWA...) addressing meteorology, atmospheric chemistry, hydrology, extreme events, health, adaptation of human societies... It is becoming a reference information system on environmental issues in West Africa: BAOBAB (Base Afrique de l'Ouest beyond AMMA Base). The projects include airborne, ground-based and ocean measurements, social science surveys, satellite data use, modelling studies and value-added product development. Therefore, the BAOBAB data portal enables to access a great amount and a large variety of data: - 250 local observation datasets, that have been collected by operational networks since 1850, long term monitoring research networks and intensive scientific campaigns; - 1350 outputs of a socio-economics questionnaire; - 60 operational satellite products and several research products; - 10 output sets of meteorological and ocean operational models and 15 of research simulations. Data documentation complies with metadata international standards, and data are delivered into standard formats. The data request interface takes full advantage of the database relational structure and enables users to elaborate multicriteria requests (period, area, property…). The BAOBAB data portal counts about 900 registered users, and 50 data requests every month. The databases and data portal have been developed and are operated jointly by SEDOO and ESPRI in France: http://baoab.sedoo.fr. The ongoing DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions over West Africa) project uses the BAOBAB portal to

  20. Radiation portal monitor system and method

    DOEpatents

    Morris, Christopher [Los Alamos, NM; Borozdin, Konstantin N [Los Alamos, NM; Green, J Andrew [Los Alamos, NM; Hogan, Gary E [Los Alamos, NM; Makela, Mark F [Los Alamos, NM; Priedhorsky, William C [Los Alamos, NM; Saunders, Alexander [Los Alamos, NM; Schultz, Larry J [Los Alamos, NM; Sossong, Michael J [Los Alamos, NM

    2009-12-15

    A portal monitoring system has a cosmic ray charged particle tracker with a plurality of drift cells. The drift cells, which can be for example aluminum drift tubes, can be arranged at least above and below a volume to be scanned to thereby track incoming and outgoing charged particles, such as cosmic ray muons, whilst also detecting gamma rays. The system can selectively detect devices or materials, such as iron, lead, gold and/or tungsten, occupying the volume from multiple scattering of the charged particles passing through the volume and can also detect any radioactive sources occupying the volume from gamma rays emitted therefrom. If necessary, the drift tubes can be sealed to eliminate the need for a gas handling system. The system can be employed to inspect occupied vehicles at border crossings for nuclear threat objects.

  1. [Portal perfusion with right gastroepiploic vein flow in liver transplant].

    PubMed

    Mendoza-Sánchez, Federico; Javier-Haro, Francisco; Mendoza-Medina, Diego Federico; González-Ojeda, Alejandro; Cortés-Lares, José Antonio; Fuentes-Orozco, Clotilde

    Liver transplantation in patients with liver cirrhosis, portal vein thrombosis, and cavernous transformation of the portal vein, is a complex procedure with high possibility of liver graft dysfunction. It is performed in 2-19% of all liver transplants, and has a significantly high mortality rate in the post-operative period. Other procedures to maintain portal perfusion have been described, however there are no reports of liver graft perfusion using right gastroepiploic vein. A 20 year-old female diagnosed with cryptogenic cirrhosis, with a Child-Pugh score of 7 points (class "B"), and MELD score of 14 points, with thrombosis and cavernous transformation of the portal vein, severe portal hypertension, splenomegaly, a history of upper gastrointestinal bleeding due to oesophageal varices, and left renal agenesis. The preoperative evaluation for liver transplantation was completed, and the right gastroepiploic vein of 1-cm diameter was observed draining to the infrahepatic inferior vena cava and right suprarenal vein. An orthotopic liver transplantation was performed from a non-living donor (deceased on January 30, 2005) using the Piggy-Back technique. Portal vein perfusion was maintained using the right gastroepiploic vein, and the outcome was satisfactory. The patient was discharged 13 days after surgery. Liver transplantation was performed satisfactorily, obtaining an acceptable outcome. In this case, the portal perfusion had adequate blood flow through the right gastroepiploic vein. Copyright © 2015 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

  2. Congenital absence of the portal vein in a cat.

    PubMed

    Holloway, Andrew; Groot, Louise; van der Schaaf, Klaartje

    2018-01-01

    A 9-month-old female neutered domestic shorthair cat presented with a history of episodic ptyalism, lethargy and abnormal behaviour. The clinical signs together with elevated pre- and post-prandial bile acid concentrations were consistent with hepatic encephalopathy (HE). In the absence of a portosystemic shunt (PSS) on abdominal ultrasound, medical management of HE was established with a protein-restricted diet and lactulose and the neurological signs resolved. Following an episode of acute vomiting and haemorrhagic diarrhoea at 19 months of age abdominal ultrasonography was repeated. The portal vein could not be demonstrated ultrasonographically; instead, portal vein tributaries were tortuous and communicated with the caudal vena cava (CdVC) at the level of the left kidney. CT angiography (CTA) confirmed the absence of the portal vein. CTA demonstrated the tortuous terminations of the portal tributaries, and several systemic veins, draining into the CdVC via a large-diameter paracaval vessel at the level of the left kidney. Gastrointestinal signs were stabilised and medical management for HE of a protein-restricted diet and lactulose was re-established. Congenital absence of the portal vein has not been described previously in the cat and should be considered in cats presenting with signs suggestive of a PSS and HE. The portal vein in the cat can be demonstrated using ultrasound, but complex congenital vascular malformations of the portal or systemic abdominal veins should be characterised using CTA and further distinguished from other vascular anomalies that may present with similar ultrasonographic features.

  3. Impact of hepatitis C oral therapy in portal hypertension.

    PubMed

    Libânio, Diogo; Marinho, Rui Tato

    2017-07-14

    Chronic hepatitis C is a leading cause of morbidity and mortality, mainly related to fibrosis/cirrhosis and portal hypertension. Direct antiviral agents are highly effective and safe and can now cure > 90% of the patients. Sustained viral response (SVR) after interferon-based regimens has been associated with improvement in liver function, fibrosis and portal hypertension in a significant proportion of patients, although a point of no return seems to exist from which viral elimination is no longer capable of preventing portal hypertension progression and liver decompensation. Indeed, although SVR is associated with improvement of hepatic venous pressure gradients and therefore a decreased risk of de novo esophageal varices, several studies show that viral clearance does not eliminate the risk of variceal progression, liver decompensation and death in patients with pre-established portal hypertension. Although evidence about the effects of direct antiviral agents (DAAs) on clinically significant outcomes is still scarce and with short follow-up, DAAs can decrease the burden of the disease if patients are timely treated before significant fibrosis and portal hypertension develops. Studies with longer follow-up are waited to establish the real magnitude of hepatitis C treatment on portal hypertension. Future studies should also focus on predictors of portal hypertension resolution since it can influence management and avoid unnecessary monitoring.

  4. Clinical role of non-invasive assessment of portal hypertension.

    PubMed

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-07

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis ( i.e ., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field.

  5. Clinical role of non-invasive assessment of portal hypertension

    PubMed Central

    Bolognesi, Massimo; Di Pascoli, Marco; Sacerdoti, David

    2017-01-01

    Measurement of portal pressure is pivotal in the evaluation of patients with liver cirrhosis. The measurement of the hepatic venous pressure gradient represents the reference method by which portal pressure is estimated. However, it is an invasive procedure that requires significant hospital resources, including experienced staff, and is associated with considerable cost. Non-invasive methods that can be reliably used to estimate the presence and the degree of portal hypertension are urgently needed in clinical practice. Biochemical and morphological parameters have been proposed for this purpose, but have shown disappointing results overall. Splanchnic Doppler ultrasonography and the analysis of microbubble contrast agent kinetics with contrast-enhanced ultrasonography have shown better accuracy for the evaluation of patients with portal hypertension. A key advancement in the non-invasive evaluation of portal hypertension has been the introduction in clinical practice of methods able to measure stiffness in the liver, as well as stiffness/congestion in the spleen. According to the data published to date, it appears to be possible to rule out clinically significant portal hypertension in patients with cirrhosis (i.e., hepatic venous pressure gradient ≥ 10 mmHg) with a level of clinically-acceptable accuracy by combining measurements of liver stiffness and spleen stiffness along with Doppler ultrasound evaluation. It is probable that the combination of these methods may also allow for the identification of patients with the most serious degree of portal hypertension, and ongoing research is helping to ensure progress in this field. PMID:28104976

  6. Endothelial dysfunction in the regulation of portal hypertension

    PubMed Central

    Iwakiri, Yasuko

    2013-01-01

    Portal hypertension is caused by an increased intrahepatic resistance, a major consequence of cirrhosis. Endothelial dysfunction in liver sinusoidal endothelial cells (LSECs) decreases the production of vasodilators, such as nitric oxide (NO) and favors vasoconstriction. This contributes to an increased vascular resistance in the intrahepatic/sinusoidal microcirculation. Portal hypertension, once developed, causes endothelial cell (EC) dysfunction in the extrahepatic, i.e. splanchnic and systemic, circulation. Unlike LSEC dysfunction, EC dysfunction in the splanchnic and systemic circulation overproduces vasodilator molecules, leading to arterial vasodilatation. In addition, portal hypertension leads to the formation of portosystemic collateral vessels. Both arterial vasodilatation and portosystemic collateral vessel formation exacerbate portal hypertension by increasing the blood flow through the portal vein. Pathologic consequences, such as esophageal varices and ascites, result. While the sequence of pathological vascular events in cirrhosis and portal hypertension have been elucidated, the underlying cellular and molecular mechanisms causing EC dysfunctions are not yet fully understood. This review article summarizes the current cellular and molecular studies on EC dysfunctions found during the development of cirrhosis and portal hypertension with a focus on intra- and extrahepatic circulation. The article ends by discussing future directions of study for EC dysfunctions. PMID:21745318

  7. Enabling OpenID Authentication for VO-integrated Portals

    NASA Astrophysics Data System (ADS)

    Plante, R.; Yekkirala, V.; Baker, W.

    2012-09-01

    To support interoperating services that share proprietary data and other user-specific information, the VAO Project provides login services for browser-based portals built on the open standard, OpenID. To help portal developers take advantage of this service, we have developed a downloadable toolkit for integrating OpenID single sign-on support into any portal. This toolkit provides APIs in a few languages commonly used on the server-side as well as a command-line version for use in any language. In addition to describing how to use this toolkit, we also discuss the general VAO framework for single sign-on. While a portal may, if it wishes, support any OpenID provider, the VAO service provides a few extra features to support VO interoperability. This includes a portal's ability to retrieve (with the user's permission) an X.509 certificate representing the authenticated user so that the portal can access other restricted services on the user's behalf. Other standard features of OpenID allow portals to request other information about the user; this feature will be used in the future for sharing information about a user's group membership to enable sharing within a group of collaborating scientists.

  8. Diagnosis and treatment of portal vein thrombosis following splenectomy.

    PubMed

    van't Riet, M; Burger, J W; van Muiswinkel, J M; Kazemier, G; Schipperus, M R; Bonjer, H J

    2000-09-01

    Portal vein thrombosis is a rare but potentially fatal complication of splenectomy. The aim of this study was to assess the incidence, risk factors, treatment and outcome of portal vein thrombosis after splenectomy in a large series of patients. All patients who had undergone a splenectomy in the University Hospital, Rotterdam, between 1984 and 1997 were reviewed retrospectively. Splenectomy that was followed by symptomatic portal vein thrombosis was selected for analysis. Risk factors for portal vein thrombosis were sought. Of 563 splenectomies, nine (2 per cent) were complicated by symptomatic portal vein thrombosis. All these patients had either fever or abdominal pain. Two of 16 patients with a myeloproliferative disorder developed portal vein thrombosis after splenectomy (P = 0.03), and four of 49 patients with haemolytic anaemia (P = 0.005). Treatment within 10 days after splenectomy was successful in all patients, while delayed treatment was ineffective. Portal vein thrombosis should be suspected in a patient with fever or abdominal pain after splenectomy. Patients with a myeloproliferative disorder or haemolytic anaemia are at higher risk; they might benefit from early detection and could have routine Doppler ultrasonography after splenectomy.

  9. Development of Geospatial Map Based Election Portal

    NASA Astrophysics Data System (ADS)

    Gupta, A. Kumar Chandra; Kumar, P.; Vasanth Kumar, N.

    2014-11-01

    The Geospatial Delhi Limited (GSDL), a Govt. of NCT of Delhi Company formed in order to provide the geospatial information of National Capital Territory of Delhi (NCTD) to the Government of National Capital Territory of Delhi (GNCTD) and its organs such as DDA, MCD, DJB, State Election Department, DMRC etc., for the benefit of all citizens of Government of National Capital Territory of Delhi (GNCTD). This paper describes the development of Geospatial Map based Election portal (GMEP) of NCT of Delhi. The portal has been developed as a map based spatial decision support system (SDSS) for pertain to planning and management of Department of Chief Electoral Officer, and as an election related information searching tools (Polling Station, Assembly and parliamentary constituency etc.,) for the citizens of NCTD. The GMEP is based on Client-Server architecture model. It has been developed using ArcGIS Server 10.0 with J2EE front-end on Microsoft Windows environment. The GMEP is scalable to enterprise SDSS with enterprise Geo Database & Virtual Private Network (VPN) connectivity. Spatial data to GMEP includes delimited precinct area boundaries of Voters Area of Polling stations, Assembly Constituency, Parliamentary Constituency, Election District, Landmark locations of Polling Stations & basic amenities (Police Stations, Hospitals, Schools and Fire Stations etc.). GMEP could help achieve not only the desired transparency and easiness in planning process but also facilitates through efficient & effective tools for management of elections. It enables a faster response to the changing ground realities in the development planning, owing to its in-built scientific approach and open-ended design.

  10. Bosonic-seesaw portal dark matter

    NASA Astrophysics Data System (ADS)

    Ishida, Hiroyuki; Matsuzaki, Shinya; Yamaguchi, Yuya

    2017-10-01

    We discuss a new type of Higgs-portal dark matter (DM) production mechanism, called the bosonic-seesaw portal (BSP) scenario. The BS provides the dynamical origin of the electroweak symmetry breaking, triggered by mixing between the elementary Higgs and a composite Higgs generated by a new-color strong dynamics, hypercolor (HC). At the HC strong coupling scale, the classical-scale invariance assumed in the model is dynamically broken, as well as the "chiral" symmetry present in the HC sector. In addition to the composite Higgs, HC baryons emerge to potentially be stable because of the unbroken HC baryon number symmetry. Hence the lightest HC baryon can be a DM candidate. Of interest in the present scenario is that HC pions can be as heavy as the HC baryon due to the possibly enhanced explicit "chiral"-breaking effect triggered after the BS mechanism, so the HC baryon pair cannot annihilate into HC pions. As in the standard setup of the freeze-in scenario, it is assumed that the DM was never in the thermal equilibrium, which ends up with no thermal abundance. It is then the non-thermal BSP process that crucially comes into the game below the HC scale: the HC baryon significantly couples to the standard-model Higgs via the BS mechanism, and can non-thermally be produced from the thermal plasma below the HC scale, which turns out to allow the TeV mass scale for the composite baryonic DM, much smaller than the generic bound placed in the conventional thermal freeze-out scenario, to account for the observed relic abundance. Thus the DM can closely be related to the mechanism of the electroweak symmetry breaking.

  11. Tsunami.gov: NOAA's Tsunami Information Portal

    NASA Astrophysics Data System (ADS)

    Shiro, B.; Carrick, J.; Hellman, S. B.; Bernard, M.; Dildine, W. P.

    2014-12-01

    We present the new Tsunami.gov website, which delivers a single authoritative source of tsunami information for the public and emergency management communities. The site efficiently merges information from NOAA's Tsunami Warning Centers (TWC's) by way of a comprehensive XML feed called Tsunami Event XML (TEX). The resulting unified view allows users to quickly see the latest tsunami alert status in geographic context without having to understand complex TWC areas of responsibility. The new site provides for the creation of a wide range of products beyond the traditional ASCII-based tsunami messages. The publication of modern formats such as Common Alerting Protocol (CAP) can drive geographically aware emergency alert systems like FEMA's Integrated Public Alert and Warning System (IPAWS). Supported are other popular information delivery systems, including email, text messaging, and social media updates. The Tsunami.gov portal allows NOAA staff to easily edit content and provides the facility for users to customize their viewing experience. In addition to access by the public, emergency managers and government officials may be offered the capability to log into the portal for special access rights to decision-making and administrative resources relevant to their respective tsunami warning systems. The site follows modern HTML5 responsive design practices for optimized use on mobile as well as non-mobile platforms. It meets all federal security and accessibility standards. Moving forward, we hope to expand Tsunami.gov to encompass tsunami-related content currently offered on separate websites, including the NOAA Tsunami Website, National Tsunami Hazard Mitigation Program, NOAA Center for Tsunami Research, National Geophysical Data Center's Tsunami Database, and National Data Buoy Center's DART Program. This project is part of the larger Tsunami Information Technology Modernization Project, which is consolidating the software architectures of NOAA's existing TWC's into

  12. Rochester Epidemiology Project Data Exploration Portal

    PubMed Central

    Grossardt, Brandon R.; Finney Rutten, Lila J.; Roger, Veronique L.; Majerus, Michelle; Jensen, Daniel W.; Brue, Scott M.; Bock-Goodner, Cynthia M.; Rocca, Walter A.

    2018-01-01

    Introduction The goal of this project was to develop an interactive, web-based tool to explore patterns of prevalence and co-occurrence of diseases using data from the expanded Rochester Epidemiology Project (E-REP) medical records-linkage system. Methods We designed the REP Data Exploration Portal (REP DEP) to include summary information for people who lived in a 27-county region of southern Minnesota and western Wisconsin on January 1, 2014 (n = 694,506; 61% of the entire population). We obtained diagnostic codes of the International Classification of Diseases, 9th edition, from the medical records-linkage system in 2009 through 2013 (5 years) and grouped them into 717 disease categories. For each condition or combination of 2 conditions (dyad), we calculated prevalence by dividing the number of persons with a specified condition (numerator) by the total number of persons in the population (denominator). We calculated observed-to-expected ratios (OERs) to test whether 2 conditions co-occur more frequently than would co-occur as a result of chance alone. Results We launched the first version of the REP DEP in May 2017. The REP DEP can be accessed at http://rochesterproject.org/portal/. Users can select 2 conditions of interest, and the REP DEP displays the overall prevalence, age-specific prevalence, and sex-specific prevalence for each condition and dyad. Also displayed are OERs overall and by age and sex and maps of county-specific prevalence of each condition and OER. Conclusion The REP DEP draws upon a medical records-linkage system to provide an innovative, rapid, interactive, free-of-charge method to examine the prevalence and co-occurrence of 717 diseases and conditions in a geographically defined population. PMID:29654640

  13. Surgery for portal hypertension in children: A 12-year review.

    PubMed

    Patel, N; Grieve, A; Hiddema, J; Botha, J; Loveland, J

    2017-11-06

    Portal hypertension is a common and potentially devastating condition in children. Notwithstanding advances in the nonsurgical management of portal hypertension, surgery remains an important treatment modality in select patients. We report here on our experience in the past 12 years. To describe the profile of, indication for, and complications of shunt surgery in children with portal hypertension. Twelve children underwent shunt surgery between 2005 and 2017. Patient records were reviewed. Fourteen procedures were performed on 12 patients during the study period. The median age at surgery was 6.5 (range 1 - 18) years. Six patients were male. Gastrointestinal bleeding that was not amenable to endoscopic control was the most common indication for surgery. Portal vein thrombosis was the most common cause of portal hypertension in our series (n=11). Two-thirds (8/12) of all patients had an identifiable underlying risk factor for portal vein thrombosis. One-third of all patients (4/12) underwent a meso-portal bypass procedure (Rex shunt), while 58% (7/12) were managed with a distal splenorenal shunt. All patients received postoperative thromboprophylaxis. We experienced a single mortality, 1 patient experienced shunt thrombosis that required revision shunt surgery, and 2 patients experienced anastomotic strictures, with one being managed with revision surgery and the other currently awaiting radiological venoplasty. Surgery is a safe and important tool in the management of children with non-cirrhotic portal hypertension and those with sufficient hepatic reserve who fail to respond to more conservative methods for the treatment of side effects of portal hypertension.

  14. Rational Classification of Portal Vein Thrombosis and Its Clinical Significance

    PubMed Central

    Ma, Jingqin; Yan, Zhiping; Luo, Jianjun; Liu, Qingxin; Wang, Jianhua; Qiu, Shijing

    2014-01-01

    Portal vein thrombosis (PVT) is commonly classified into acute (symptom duration <60 days and absence of portal carvernoma and portal hypertension) and chronic types. However, the rationality of this classification has received little attention. In this study, 60 patients (40 men and 20 women) with PVT were examined using contrast-enhanced computed tomography (CT). The percentage of vein occlusion, including portal vein (PV) and superior mesenteric vein (SMV), was measured on CT image. Of 60 patients, 17 (28.3%) met the criterion of acute PVT. Symptoms occurred more frequently in patients with superior mesenteric vein thrombosis (SMVT) compared to those without SMVT (p<0.001). However, there was no significant difference in PV occlusion between patients with and without symptoms. The frequency of cavernous transformation was significantly higher in patients with complete PVT than those with partial PVT (p<0.001). Complications of portal hypertension were significantly associated with cirrhosis (p<0.001) rather than with the severity of PVT and presence of cavernoma. These results suggest that the severity of PVT is only associated with the formation of portal cavernoma but unrelated to the onset of symptoms and the development of portal hypertension. We classified PVT into complete and partial types, and each was subclassified into with and without portal cavernoma. In conclusion, neither symptom duration nor cavernous transformation can clearly distinguish between acute and chronic PVT. The new classification system can determine the pathological alterations of PVT, patency of portal vein and outcome of treatment in a longitudinal study. PMID:25393320

  15. Metastable Defect Formation at Microvoids Identified as a Source of Light-Induced Degradation in a-Si :H

    NASA Astrophysics Data System (ADS)

    Fehr, M.; Schnegg, A.; Rech, B.; Astakhov, O.; Finger, F.; Bittl, R.; Teutloff, C.; Lips, K.

    2014-02-01

    Light-induced degradation of hydrogenated amorphous silicon (a-Si :H), known as the Staebler-Wronski effect, has been studied by time-domain pulsed electron-paramagnetic resonance. Electron-spin echo relaxation measurements in the annealed and light-soaked state revealed two types of defects (termed type I and II), which can be discerned by their electron-spin echo relaxation. Type I exhibits a monoexponential decay related to indirect flip-flop processes between dipolar coupled electron spins in defect clusters, while the phase relaxation of type II is dominated by H1 nuclear spin dynamics and is indicative for isolated spins. We propose that defects are either located at internal surfaces of microvoids (type I) or are isolated and uniformly distributed in the bulk (type II). The concentration of both defect type I and II is significantly higher in the light-soaked state compared to the annealed state. Our results indicate that in addition to isolated defects, defects on internal surfaces of microvoids play a role in light-induced degradation of device-quality a-Si :H.

  16. SU-F-T-283: A Novel Device to Enable Portal Dosimetry for Flattening Filter Free Beams

    SciTech Connect

    Faught, A; Wu, Q; Adamson, J

    Purpose: Varian’s electronic portal imaging device (EPID) based portal dosimetry tool is a popular and effective means of performing IMRT QA. EPIDs for older models of the TrueBeam accelerator utilize a 40cmx30cm Image Detection Unit (IDU) that saturates at the center for standard source to imager distances with high dose rate flattening filter free (FFF) beams. This makes portal dosimetry not possible and an alternative means of IMRT QA necessary. We developed a filter that would attenuate the beam to a dose rate measureable by the IDU for portal dosimetry IMRT QA. Methods: Multipurpose 304 stainless steel plates were placedmore » on an accessory tray to attenuate the beam. Profiles of an open field measured on the IDU were acquired with varying number of plates to assess the thickness needed to reduce the maximum dose rates of 6XFFF and 10XFFF beams to measurable levels. A new portal dose image prediction (PDIP) model was commissioned based on open field measurements with plates in position, and a modified beam profile was input to portal dosimetry calibration at the console to empirically correct for attenuation and scatter. The portal dosimetry tool was used to assess agreement between predicted and measured doses for open 25×25cm{sup 2} fields and intensity modulated fields using 6XFFF and 10XFFF beams. Results: Thicknesses of 2.5cm and 3.8cm of steel were required to reduce the highest dose rates to a measureable level for 6XFFF and 10XFFF, respectively. Gamma analysis using a 3%/3mm relative criterion with the filter in place and using the new PDIP model resulted in 98.2% and 93.6% of pixels passing while intensity modulated fields showed passing rates of 98.2% and 99.0%. Conclusion: Use of the filter allows for portal dosimetry to be used for IMRT QA of FFF plans in place of purchasing a second option for IMRT QA.« less

  17. Portal dosimetry for VMAT using integrated images obtained during treatment

    SciTech Connect

    Bedford, James L., E-mail: James.Bedford@icr.ac.uk; Hanson, Ian M.; Hansen, Vibeke Nordmark

    2014-02-15

    Purpose: Portal dosimetry provides an accurate and convenient means of verifying dose delivered to the patient. A simple method for carrying out portal dosimetry for volumetric modulated arc therapy (VMAT) is described, together with phantom measurements demonstrating the validity of the approach. Methods: Portal images were predicted by projecting dose in the isocentric plane through to the portal image plane, with exponential attenuation and convolution with a double-Gaussian scatter function. Appropriate parameters for the projection were selected by fitting the calculation model to portal images measured on an iViewGT portal imager (Elekta AB, Stockholm, Sweden) for a variety of phantommore » thicknesses and field sizes. This model was then used to predict the portal image resulting from each control point of a VMAT arc. Finally, all these control point images were summed to predict the overall integrated portal image for the whole arc. The calculated and measured integrated portal images were compared for three lung and three esophagus plans delivered to a thorax phantom, and three prostate plans delivered to a homogeneous phantom, using a gamma index for 3% and 3 mm. A 0.6 cm{sup 3} ionization chamber was used to verify the planned isocentric dose. The sensitivity of this method to errors in monitor units, field shaping, gantry angle, and phantom position was also evaluated by means of computer simulations. Results: The calculation model for portal dose prediction was able to accurately compute the portal images due to simple square fields delivered to solid water phantoms. The integrated images of VMAT treatments delivered to phantoms were also correctly predicted by the method. The proportion of the images with a gamma index of less than unity was 93.7% ± 3.0% (1SD) and the difference between isocenter dose calculated by the planning system and measured by the ionization chamber was 0.8% ± 1.0%. The method was highly sensitive to errors in monitor units

  18. Liver regeneration after different degrees of portal vein ligation.

    PubMed

    Lauber, David Tibor; Tihanyi, Dóra Krisztina; Czigány, Zoltán; Kovács, Tibor; Budai, András; Drozgyik, Dóra; Fülöp, András; Szijártó, Attila

    2016-06-15

    Selective portal vein ligation (PVL) is followed by ipsilateral atrophy and contralateral hypertrophy of the liver lobes. Although the atrophy-hypertrophy complex induced by PVL is a well-documented phenomenon, the effect of different degrees of extended portal vein occlusion on liver regeneration is not known. The aim of this study was to assess the effects of different degrees of portal occlusion on portal pressure and liver regeneration. Male Wistar rats (n = 96; 220-250 g) were randomized into three groups and underwent 70%, 80%, or 90% portal vein ligation, respectively. The portal pressure was measured immediately and 24, 48, 72, 120, and 168 h after PVL (n = 6/group/time point). The hepatic lobes and the spleen were weighed, and liver regeneration ratio was calculated. Changes in liver histology and the mitotic activity were assessed on hematoxylin-eosin stained slides. Higher degree of portal occlusion triggered a stronger regenerative response (regeneration ratio of PVL 70%168h = 2.23 ± 0.13, PVL 80%168h = 3.11 ± 0.37, PVL 90%168h = 4.68 ± 0.48) PVL led to an immediate increase in portal pressure, the value of which changed proportionally to the mass of liver tissue deprived of portal perfusion (PVL 70%acute = 17 ± 2 mm Hg, PVL 80%acute = 19 ± 1 mm Hg, PVL 90%acute = 26 ± 4 mm Hg). Findings in histology showed necro-apoptotic lesions in the atrophic liver lobes and increased mitotic cell count in the hypertrophic lobes. The mitotic cell count of PVL 90% peaked earlier and at a significantly higher value than of PVL 70% and PVL 80% (PVL 9024h%: 96.0 ± 3.5 PVL 70%48h: 64.0 ± 2.1, PVL 80%48h: 56.3 ± 4.0). The mitotic index after 24 h showed a strong correlation with the acute portal hypertension. A higher degree of portal vein occlusion leads to a greater regenerative response, presumably triggered by the proportional increase in portal pressure, which supports the role of the so-called "blood-flow" theory of PVL-triggered liver

  19. 3. East portal of Tunnel 27, view to northeast from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. East portal of Tunnel 27, view to northeast from atop cut bank, 210mm lens. This view shows to good effect the original construction of the Harriman period tunnels, which were concreted fifty feet in from the portals with the balance being timber lined. In 1965 the east end of the tunnel collapsed, with the result that approximately 115 feet of the east end was 'daylighted' and the original east portal and concreted end were left in place, free-standing as seen here. - Central Pacific Transcontinental Railroad, Tunnel No. 27, Milepost 133.9, Applegate, Placer County, CA

  20. Use of a Si(Li) detector as β spectrometer.

    PubMed

    Dryák, P; Kovář, P

    2014-05-01

    The aim of this work is to demonstrate the capability of a Si(Li) detector for the measurement of β spectra, despite the energy absorption in air and in the Be window. A simple source holder fixes the source on the symmetry axis at 3mm from the detector window. The β-sources are produced by evaporation on a plastic backing plate. Absorbing materials between the source and the sensitive volume of the detector are 3 mm of air, a Be window, 0.1 μm Si and 20 nm of gold. A model of the detector was created for β spectra simulation using the MCNP 4A code. Experimental spectra of (14)C, (147)Pm, (204)Tl, (90)Sr/(90)Y were compared with simulated spectra. © 2013 Published by Elsevier Ltd.

  1. Blood in the gastric lumen increases splanchnic blood flow and portal pressure in portal-hypertensive rats.

    PubMed

    Chen, L; Groszmann, R J

    1996-10-01

    In portal-hypertensive humans, portal blood flow and pressure increase after a meal. These hemodynamic changes may increase variceal rupture risk. The aim of this study was to determine whether blood in the stomach lumen increases splanchnic flow and portal pressure (PP) in portal-hypertensive rats. superior mesenteric artery flow and PP were measured in conscious, unrestrained, fasted partial portal vein-ligated rats with chronically implanted Doppler flow probes or portal vein catheters before and after gavage with heparinized, warmed blood from donor rats, air, standard meal, or empty tube. Percentage of changes in flow and pressure from baseline were significantly greater after gavage with blood (an increase of 22.6% +/- 3.5% and an increase of 16.4% +/- 3.1%, respectively) than empty tube (an increase of 3.4% +/- 0.6% and a decrease of 5.4% +/- 3.5%, respectively) (P < 0.005). Percentage of changes in flow and pressure were slightly but insignificantly greater after gavage with air vs. empty tube (P < 0.005). In portal-hypertensive rats, blood in the stomach lumen significantly increases splanchnic blood flow and PP. Splanchnic hyperemia from absorption of blood's calories probably contributes to these hemodynamic changes. In patients with variceal hemorrhage, blood in the stomach may increase the risk of persistent variceal bleeding or rebleeding.

  2. Mouse and Rat Models of Induction of Hepatic Fibrosis and Assessment of Portal Hypertension.

    PubMed

    Klein, Sabine; Schierwagen, Robert; Uschner, Frank Erhard; Trebicka, Jonel

    2017-01-01

    Portal hypertension either develops due to progressive liver fibrosis or is the consequence of vascular liver diseases such as portal vein thrombosis or non-cirrhotic portal hypertension. This chapter focuses on different rodent models of liver fibrosis with portal hypertension and also in few non-cirrhotic portal hypertension models. Importantly, after the development of portal hypertension, the proper assessment of drug effects in the portal and systemic circulation should be discussed. The last part of the chapter is dedicated in these techniques to assess the in vivo hemodynamics and the ex vivo techniques of the isolated liver perfusion and vascular contractility.

  3. Development of the UTAUT2 model to measure the acceptance of medical laboratory portals by patients in Shiraz

    PubMed Central

    Ravangard, Ramin; Kazemi, Zhila; Abbasali, Somaye Zaker; Sharifian, Roxana; Monem, Hossein

    2017-01-01

    Introduction One of the main stages for achieving the success is acceptance of technology by its users. Hence, identifying the effective factors in successful acceptance of information technology is necessary and vital. One such factor is usability. This study aimed to investigate the software usability in the “Unified Theory of Acceptance and Use of Technology 2 (UTAUT2)” model in patients’ use of medical diagnosis laboratories’ electronic portals in 2015. Methods This cross-sectional study was carried out on 170 patients in 2015. A 27-item questionnaire adopted from previous research and the Usability Evaluation questionnaire were used for data collection. Data were analyzed using Structural Equation Modeling (SEM), with Partial Least Squares approach by SPSS 20.0 and Smart-PLS V3.0. Results The results showed that the construct of intention to use had significant associations with price value (t-value=2.77), hedonic motivation (t-value=4.46), habit (t-value=1.99) and usability (t-value=5.2), as well as the construct of usage behavior with usability (t-value=3.45) and intention to use (t-value=2.03). Conclusion Considering the results of this study, the following recommendations can be made in order for the higher use of portals by the patients: informing patients about the advantages of using these portals, designing portals in a simple and understandable form, increasing the portals’ attractiveness, etc. PMID:28465819

  4. Case studies in geographic information systems for internet portals

    DOT National Transportation Integrated Search

    2012-06-30

    The following report investigates the experiences of transportation agencies in the deployment of Internet-based mapping portals based on GIS. It presents background information, a series of case studies, and a summary of conclusions given the experi...

  5. [Set-up, portals and normal exploration in wrist arthroscopy].

    PubMed

    Atzei, A; Luchetti, R; Sgarbossa, A; Carità, E; Llusà, M

    2006-11-01

    Arthroscopy is an accepted technique for evaluation of intra-articular pathology and treatment of a variety of disorders even in the wrist joint. Dedicated miniaturized instrumentation is needed along with a specific traction system. The external distraction alone (dry technique) allows for complete joint exploration and several type of arthroscopic surgery, avoiding annoying leaking in the subcutaneous tissues, though further distension of the articular pouches can be achieved by saline infusion (fluid distension or wet technique). Knowledge of surface anatomic landmarks and careful surgical technique are required for proper portal placement and in order to avoid injury to the numerous noble structures crossing nearby. Description of radio- and medio-carpal portals is provided along with the different bony, condral, synovial and ligamentous structures that can be visualised or treated through each portal. Surgeon can choose the most suitable portal for scope or instruments, according to specific needs for diagnostic or therapeutic purposes.

  6. [Set-up, portals and normal exploration in wrist arthroscopy.

    PubMed

    Atzei, A; Luchetti, R; Sgarbossa, A; Carità, E; Llusà, M

    2006-11-01

    Arthroscopy is an accepted technique for evaluation of intra-articular pathology and treatment of a variety of disorders even in the wrist joint. Dedicated miniaturized instrumentation is needed along with a specific traction system. The external distraction alone (dry technique) allows for complete joint exploration and several type of arthroscopic surgery, avoiding annoying leaking in the subcutaneous tissues, though further distension of the articular pouches can be achieved by saline infusion (fluid distension or wet technique). Knowledge of surface anatomic landmarks and careful surgical technique are required for proper portal placement and in order to avoid injury to the numerous noble structures crossing nearby. Description of radio- and medio-carpal portals is provided along with the different bony, condral, synovial and ligamentous structures that can be visualised or treated through each portal. Surgeon can choose the most suitable portal for scope or instruments, according to specific needs for diagnostic or therapeutic purposes.

  7. The portals 4.0.1 network programming interface.

    SciTech Connect

    Barrett, Brian W.; Brightwell, Ronald Brian; Pedretti, Kevin

    2013-04-01

    This report presents a specification for the Portals 4.0 network programming interface. Portals 4.0 is intended to allow scalable, high-performance network communication between nodes of a parallel computing system. Portals 4.0 is well suited to massively parallel processing and embedded systems. Portals 4.0 represents an adaption of the data movement layer developed for massively parallel processing platforms, such as the 4500-node Intel TeraFLOPS machine. Sandias Cplant cluster project motivated the development of Version 3.0, which was later extended to Version 3.3 as part of the Cray Red Storm machine and XT line. Version 4.0 is targeted to the next generationmore » of machines employing advanced network interface architectures that support enhanced offload capabilities. 3« less

  8. The Portals 4.0 network programming interface.

    SciTech Connect

    Barrett, Brian W.; Brightwell, Ronald Brian; Pedretti, Kevin

    2012-11-01

    This report presents a specification for the Portals 4.0 network programming interface. Portals 4.0 is intended to allow scalable, high-performance network communication between nodes of a parallel computing system. Portals 4.0 is well suited to massively parallel processing and embedded systems. Portals 4.0 represents an adaption of the data movement layer developed for massively parallel processing platforms, such as the 4500-node Intel TeraFLOPS machine. Sandias Cplant cluster project motivated the development of Version 3.0, which was later extended to Version 3.3 as part of the Cray Red Storm machine and XT line. Version 4.0 is targeted to the next generationmore » of machines employing advanced network interface architectures that support enhanced offload capabilities.« less

  9. Knowledge portal: a tool to capture university requirements

    NASA Astrophysics Data System (ADS)

    Mansourvar, Marjan; Binti Mohd Yasin, Norizan

    2011-10-01

    New technologies, especially, the Internet have made a huge impact on knowledge management and information dissemination in education. The web portal as a knowledge management system is very popular topics in many organizations including universities. Generally, a web portal defines as a gateway to online network accessible resources through the intranet, extranet or Internet. This study develops a knowledge portal for the students in the Faculty of Computer Science and Information Technology (FCSIT), University of Malaya (UM). The goals of this portal are to provide information for the students to help them to choose the right courses and major that are relevant to their intended future jobs or career in IT. A quantitative approach used as the selected method for this research. Quantitative method provides an easy and useful way to collect data from a large sample population.

  10. EAST (CANADIAN) PORTAL OF MAIN SECTION OF BRIDGE, SHOWING PANEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EAST (CANADIAN) PORTAL OF MAIN SECTION OF BRIDGE, SHOWING PANEL OVER PIER C IN CENTER. VIEW TO WEST. - Blue Water Bridge, Spanning St. Clair River at I-69, I-94, & Canadian Route 402, Port Huron, St. Clair County, MI

  11. 11. Detailed view of sign, portal strut, lattice work, and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Detailed view of sign, portal strut, lattice work, and diagonal eye-bars, (Nov. 30, 1988) - University Heights Bridge, Spanning Harlem River at 207th Street & West Harlem Road, New York County, NY

  12. 7. Straighton view of east portal. Jack Boucher, photographer, 1977 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Straight-on view of east portal. Jack Boucher, photographer, 1977 - Neshanic Station Lenticular Truss Bridge, State Route 567, spanning South Branch of Raritan River, Neshanic Station, Somerset County, NJ

  13. 2. CONFLUENCE POOL, DETAIL OF TUNNEL PORTAL WITH WATER ENTERING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. CONFLUENCE POOL, DETAIL OF TUNNEL PORTAL WITH WATER ENTERING FROM SANTA ANA RIVER. VIEW TO NORTHEAST. - Santa Ana River Hydroelectric System, Bear Creek Diversion Dam & Confluence Pool, Redlands, San Bernardino County, CA

  14. 4. APPROACH OF CARRS MILL ROAD TO THE SOUTH PORTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. APPROACH OF CARRS MILL ROAD TO THE SOUTH PORTAL OF THE MITCHELLS MILL BRIDGE; VIEW TO NORTH. - Mitchell's Mill Bridge, Spanning Winter's Run on Carrs Mill Road, west of Bel Air, Bel Air, Harford County, MD

  15. Assay Portal | Office of Cancer Clinical Proteomics Research

    Cancer.gov

    The CPTAC Assay Portal serves as a centralized public repository of "fit-for-purpose," multiplexed quantitative mass spectrometry-based proteomic targeted assays. Targeted proteomic assays eliminate issues that are commonly observed using conventional protein detection systems.

  16. 7. Detail of Minnesota (southeast) portal of bridge, from the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Detail of Minnesota (southeast) portal of bridge, from the southeast - Enloe Bridge No. 90021, Spanning Red River of North between Minnesota & North Dakota on County State Aid Highway 28, Wolverton, Wilkin County, MN

  17. Oblique perspective of portal, due north. Bridge has gable roof ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Oblique perspective of portal, due north. Bridge has gable roof clad with wood shingles and has board and batten siding. - Watson Mill Bridge, Spanning South Fork Broad River, Watson Mill Road, Watson Mill Bridge State Park, Comer, Madison County, GA

  18. 6. VIEW OF SWITCH ROOM, POWERHOUSE, SHOWING TRANSFORMER CABLE PORTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW OF SWITCH ROOM, POWERHOUSE, SHOWING TRANSFORMER CABLE PORTAL BAY, LOOKING SOUTH - Nine Mile Hydroelectric Development, Powerhouse, State Highway 291 along Spokane River, Nine Mile Falls, Spokane County, WA

  19. Integrating Space Communication Network Capabilities via Web Portal Technologies

    NASA Technical Reports Server (NTRS)

    Johnston, Mark D.; Lee, Carlyn-Ann; Lau, Chi-Wung; Cheung, Kar-Ming; Levesque, Michael; Carruth, Butch; Coffman, Adam; Wallace, Mike

    2014-01-01

    We have developed a service portal prototype as part of an investigation into the feasibility of using Java portlet technology as a means of providing integrated access to NASA communications network services. Portal servers provide an attractive platform for this role due to the various built-in collaboration applications they can provide, combined with the possibility to develop custom inter-operating portlets to extent their functionality while preserving common presentation and behavior. This paper describes various options for integration of network services related to planning and scheduling, and results based on use of a popular open-source portal framework. Plans are underway to develop an operational SCaN Service Portal, building on the experiences reported here.

  20. 9. DETAIL OF PRATT DECK TRUSS, AND NORTH PORTAL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAIL OF PRATT DECK TRUSS, AND NORTH PORTAL OF PENNSYLVANIA PETIT TRUSS WITH CONCRETE SUPPORTING PIER, LOOKING SOUTHWEST - James Bethel Gresham Memorial Bridge, Spanning Green Pond River at Kentucky Route 81, Calhoun, McLean County, KY

  1. 17. DETAIL OF SOUTH PORTAL, SHOWING "TREE OF LIFE" RAILING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DETAIL OF SOUTH PORTAL, SHOWING "TREE OF LIFE" RAILING DETAIL AS WELL AS BUILDER'S PLATE. - Falls Bridge, Spanning Schuylkill River, connecting East & West River Drives, Philadelphia, Philadelphia County, PA

  2. Detail; south (front) elevation, second floor, center portal of loggia ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail; south (front) elevation, second floor, center portal of loggia - North Philadelphia Station, 2900 North Broad Street, on northwest corner of Broad Street & Glenwood Avenue, Philadelphia, Philadelphia County, PA

  3. Cut at eastern approach, with portal obscured by train entering ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cut at eastern approach, with portal obscured by train entering tunnel, looking NNW. - Philadelphia & Reading Railroad, Black Rock Tunnel, Beneath Black Rock Hill, southwest of Black Rock Dam, Phoenixville, Chester County, PA

  4. View of entry portal into bomb shelter. Wood blocking has ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of entry portal into bomb shelter. Wood blocking has been installed to prevent entry, view facing north - U.S. Naval Base, Pearl Harbor, Splinterproof Shelter, Seventh Street between Avenues E & G, Pearl City, Honolulu County, HI

  5. View of entry portal into bomb shelter. Wood blocking has ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of entry portal into bomb shelter. Wood blocking has been installed to prevent entry, view facing northwest - U.S. Naval Base, Pearl Harbor, Splinterproof Shelter, Seventh Street between Avenues E & G, Pearl City, Honolulu County, HI

  6. 4. East portal of Tunnel 25, view to southwest from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. East portal of Tunnel 25, view to southwest from west end of Tunnel 26 (HAER CA-202), 135mm lens. - Central Pacific Transcontinental Railroad, Tunnel No. 25, Milepost 133.09, Applegate, Placer County, CA

  7. 1. West portal of Tunnel 25, contextual view to northeast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. West portal of Tunnel 25, contextual view to northeast from Tunnel 24 (HAER CA-200), 135mm lens. - Central Pacific Transcontinental Railroad, Tunnel No. 25, Milepost 133.09, Applegate, Placer County, CA

  8. View north from within mining cut; portal of Fowler Lode ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View north from within mining cut; portal of Fowler Lode Adit (6'-long range pole for scale) - Steamboat Mine, Southeast slope of Steamboat Mountain, west of the junction of Forest Service Roads 1000300 and 1000365, Jacksonville, Jackson County, OR

  9. Building Your Campus Portal: Advice from the Field.

    ERIC Educational Resources Information Center

    Krebs, Arlene

    2001-01-01

    Discusses portal technology in higher education, including planning, design, technical, and financial issues. Highlights include determining the customers; marketing possibilities for the university; ownership issues; data design; effective cost structuring; security issues; adaptability; content; and customer input and feedback. (LRW)

  10. 3. DETAIL OF TRUSS PANELS AND INCLINED PORTAL MEMBER AT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. DETAIL OF TRUSS PANELS AND INCLINED PORTAL MEMBER AT THE SOUTHEAST ENTRANCE TO THE BRIDGE, LOOKING WEST. - Chicago, Madison & Northern Railroad, Sanitary & Ship Canal Bridge, Spanning Sanitary & Ship Canal, east of Kedzie Avenue, Chicago, Cook County, IL

  11. 2. PORTAL VIEW OF BRIDGE FROM NORTH SIDE OF SANITARY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. PORTAL VIEW OF BRIDGE FROM NORTH SIDE OF SANITARY AND SHIP CANAL, LOOKING SOUTHEAST. - Chicago, Madison & Northern Railroad, Sanitary & Ship Canal Bridge, Spanning Sanitary & Ship Canal, east of Kedzie Avenue, Chicago, Cook County, IL

  12. 13. DETAIL VIEW OF VIADUCTS AND TUNNEL PORTAL FROM SAME ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. DETAIL VIEW OF VIADUCTS AND TUNNEL PORTAL FROM SAME CAMERA POSITION AS NO. CA-265-J-15. LOOKING 234°SW. - Arroyo Seco Parkway, Figueroa Street Viaduct, Spanning Los Angeles River, Los Angeles, Los Angeles County, CA

  13. Popular Tasks in the ForeSee Portal

    EPA Pesticide Factsheets

    Access the robust American Customer Satisfaction Index Portal to obtain information, such as search terms used by survey respondents, satisfaction by audience type, and responses to specific survey questions; and learn how to use various filters.

  14. Statistical analyses of Higgs- and Z -portal dark matter models

    NASA Astrophysics Data System (ADS)

    Ellis, John; Fowlie, Andrew; Marzola, Luca; Raidal, Martti

    2018-06-01

    We perform frequentist and Bayesian statistical analyses of Higgs- and Z -portal models of dark matter particles with spin 0, 1 /2 , and 1. Our analyses incorporate data from direct detection and indirect detection experiments, as well as LHC searches for monojet and monophoton events, and we also analyze the potential impacts of future direct detection experiments. We find acceptable regions of the parameter spaces for Higgs-portal models with real scalar, neutral vector, Majorana, or Dirac fermion dark matter particles, and Z -portal models with Majorana or Dirac fermion dark matter particles. In many of these cases, there are interesting prospects for discovering dark matter particles in Higgs or Z decays, as well as dark matter particles weighing ≳100 GeV . Negative results from planned direct detection experiments would still allow acceptable regions for Higgs- and Z -portal models with Majorana or Dirac fermion dark matter particles.

  15. Design of Grid Portal System Based on RIA

    NASA Astrophysics Data System (ADS)

    Cao, Caifeng; Luo, Jianguo; Qiu, Zhixin

    Grid portal is an important branch of grid research. In order to solve the weak expressive force, the poor interaction, the low operating efficiency and other insufficiencies of the first and second generation of grid portal system, RIA technology was introduced to it. A new portal architecture was designed based on RIA and Web service. The concrete realizing scheme of portal system was presented by using Adobe Flex/Flash technology, which formed a new design pattern. In system architecture, the design pattern has B/S and C/S superiorities, balances server and its client side, optimizes the system performance, realizes platform irrelevance. In system function, the design pattern realizes grid service call, provides client interface with rich user experience, integrates local resources by using FABridge, LCDS, Flash player and some other components.

  16. View of the Colorado River Canyon showing lower portal road ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the Colorado River Canyon showing lower portal road in background taken from the rim of Hoover Dam, view south - Hoover Dam, Spanning Colorado River at Route 93, Boulder City, Clark County, NV

  17. 15. SOUTH WEB AND WEST PORTAL OF MIDDLE THROUGH TRUSS. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. SOUTH WEB AND WEST PORTAL OF MIDDLE THROUGH TRUSS. VIEW TO NORTHEAST. - Abraham Lincoln Memorial Bridge, Spanning Missouri River on Highway 30 between Nebraska & Iowa, Blair, Washington County, NE

  18. 7. NORTH WEB AND WEST PORTAL. VIEW TO SOUTHEAST FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. NORTH WEB AND WEST PORTAL. VIEW TO SOUTHEAST FROM BLAIR RAILROAD BRIDGE. - Abraham Lincoln Memorial Bridge, Spanning Missouri River on Highway 30 between Nebraska & Iowa, Blair, Washington County, NE

  19. A portal for the ocean biogeographic information system

    USGS Publications Warehouse

    Zhang, Yunqing; Grassle, J. F.

    2002-01-01

    Since its inception in 1999 the Ocean Biogeographic Information System (OBIS) has developed into an international science program as well as a globally distributed network of biogeographic databases. An OBIS portal at Rutgers University provides the links and functional interoperability among member database systems. Protocols and standards have been established to support effective communication between the portal and these functional units. The portal provides distributed data searching, a taxonomy name service, a GIS with access to relevant environmental data, biological modeling, and education modules for mariners, students, environmental managers, and scientists. The portal will integrate Census of Marine Life field projects, national data archives, and other functional modules, and provides for network-wide analyses and modeling tools.

  20. Detail of inside of inclined end post, with portal cross ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of inside of inclined end post, with portal cross bar member. - Phoenix Iron Company, French Creek Bridge, Spanning French Creek between Gay Street & Main Street, Phoenixville, Chester County, PA

  1. Outsourcing the Portal: Another Branch in the Decision Tree.

    ERIC Educational Resources Information Center

    McMahon, Tim

    2000-01-01

    Discussion of the management of information resources in organizations focuses on the use of portal technologies to update intranet capabilities. Considers application outsourcing decisions, reviews benefits (including reducing costs) as well as concerns, and describes application service providers (ASPs). (LRW)

  2. Protection of estrogen in portal hypertension gastropathy: an experimental model.

    PubMed

    Morgan-Martins, Maria Isabel; Jacques, Simone Iahnig; Hartmann, Renata Minuzzo; Marques, Camila Moraes; Marroni, Cláudio Augusto; Marroni, Norma Possa

    2011-01-01

    Portal hypertension is a complication secondary to cirrhosis that is characterized by increased blood flow and/or vascular resistance in the portal system, causing the appearance of a hyperdynamic collateral circulation. Partial portal vein ligation is an experimental model used in rats to study the pathophysiological mechanisms involved in pre-hepatic portal hypertension. Estrogen E2 is an antioxidant molecule with various physiological actions. To evaluate the antioxidant activity of endogenous estrogen in an experimental model of partial portal vein ligation by comparing intact with castrated rats. Twenty Wistar rats, weighing on average 250 g were used and divided into four groups: sham-operated (SO); intact (I) with partial portal vein ligation (I + PPVL), castrated (C) and castrated with partial ligation of the vein (C + PPVL). Day 1: castration or sham-operation; day 7, PPVL surgery; on day 15 post-PPVL, portal pressure in the mesenteric vein of rats was measured on polygraph Letica. Lipid peroxidation in the stomach was assessed using the technique of thiobarbituric acid reactive substances and activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase. Statistical analysis was done with ANOVA - Student-Newman-Keuls (mean ± SE), and P<0.05 was considered as significant. Portal pressure was significantly increased in C + PPVL as compared to the other groups. There was no significant difference in the group of intact rats. TBARS showed significant damage in C and C + PPVL in relation to others. Antioxidant enzymes were significantly increased in the castrated rats with subsequent PPVL as compared to the other groups. We suggest that estrogen E2 plays a protective role in intact compared with castrated rats because it presents hydrophenolic radicals in its molecule, thus acting as an antioxidant in this experimental model.

  3. 2. West portal of Tunnel 3, oblique view to northnorthwest, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. West portal of Tunnel 3, oblique view to north-northwest, 135mm lens. Note the simple concrete portal face and wingwalls, characteristic of the later (1923-27) period of construction on the Natron Cutoff. Note also the extreme surface spalling of the concrete, evidence of the severe freeze-thaw cycle at this elevation. - Southern Pacific Railroad Natron Cutoff, Tunnel 3, Milepost 537.77, Odell Lake, Klamath County, OR

  4. Spontaneous Intrahepatic Portal Venous Shunt: Presentation and Endovascular Treatment.

    PubMed

    Sheth, Nakul; Sabbah, Nathanael; Contractor, Sohail

    2016-07-01

    Spontaneous intrahepatic portal venous shunts are rare with only few case reports published. Treatments using various endovascular techniques have been described, although no single technique has been shown to be preferred. We present a patient who was referred for treatment of a spontaneous portal venous shunt and describe our treatment approach and present a review on previously reported cases. © The Author(s) 2016.

  5. Beginning hip arthroscopy: indications, positioning, portals, basic techniques, and complications.

    PubMed

    Smart, L Ryan; Oetgen, Matthew; Noonan, Benjamin; Medvecky, Michael

    2007-12-01

    Hip arthroscopy is becoming increasingly popular for the diagnosis and treatment of hip pathology, and the indications continue to evolve. The two most common approaches are the supine and lateral decubitus position. Both approaches can be performed effectively; however, each approach has its own benefits and drawbacks. In this review we will describe the indications for hip arthroscopy, the pros and cons of each approach, and the necessary equipment, portals, portal placement, commercially available distraction devices, and complications.

  6. Portal vein thrombosis and liver abscess due to Lactococcus lactis.

    PubMed

    Güz, Galip; Yeğin, Zeynep Arzu; Doğan, Ibrahim; Hizel, Kenan; Bali, Musa; Sindel, Sükrü

    2006-06-01

    A 26-year-old man was admitted with fever and abdominal pain. Abdominal ultrasonography and Doppler ultrasound eventually revealed portal vein thrombosis and a pyogenic liver abscess (17x11x11 cm). Lactococcus lactis was isolated from a culture of the abscess material. This organism is not a common pathogen in humans. This is the first published description of portal vein thrombosis and pyogenic liver abscess due to L. lactis.

  7. Structural and electrical investigations of a-Si:H(i) and a-Si:H(n+) stacked layers for improving the interface and passivation qualities

    NASA Astrophysics Data System (ADS)

    Hsieh, Yu-Lin; Lee, Chien-Chieh; Lu, Chia-Cheng; Fuh, Yiin-Kuen; Chang, Jenq-Yang; Lee, Ju-Yi; Li, Tomi T.

    2017-07-01

    A symmetrically stacked structure [(a-Si:H(n+)/a-Si:H(i)/CZ wafer (n)/a-Si:H(i)/a-Si:H(n+)] was used to optimize the growth process conditions of the n-type hydrogenated amorphous silicon [a-Si:H(n+)] thin films. Here a-Si:H(n+) film was used as back surface field (BSF) layer for the silicon heterojunction solar cell and all stacked films were prepared by conventional radio-frequency plasma-enhanced chemical vapor deposition. The characterizations of the effective carrier lifetime (τeff), electrical and structural properties, as well as correlation with the hydrogen dilution ratio (R=H2/SiH4) were systematically discussed with the emphasis on the effectiveness of the passivation layer using the lifetime tester, spectroscopic ellipsometry, and hall measurement. High quality of a stacked BSF layer (intrinsic/n-type a-Si:H layer) with effective carrier lifetime of 1.8 ms can be consistently obtained. This improved passivation layer can be primarily attributed to the synergy of chemical and field effect to significantly reduce the surface recombination.

  8. Examining the Role of Anxiety and Apathy in Health Consumers' Intentions to Use Patient Health Portals for Personal Health Information Management

    ERIC Educational Resources Information Center

    Torres, Carlos A.

    2011-01-01

    This study investigated college students' attitudes toward and intentions to use personal health portals (PHPs) for managing their personal health information using a survey method. The study also aimed to examine the roles electronic Personal Health Information Management (PHIM) anxiety and apathy play in influencing students' attitudes toward…

  9. Effects of various gate materials on electrical degradation of a-Si:H TFT in industrial display application

    NASA Astrophysics Data System (ADS)

    Ho, Ching-Yuan; Chang, Yaw-Jen

    2016-02-01

    Both aluminum (Al) and copper (Cu), acting as transmission lines in the hydrogenated amorphous silicon of a thin film transistor (a-Si:H TFT), were studied to investigate electrical degradation including electron-migration (EM) and threshold voltage (Vt) stability and recovery performance. Under long-term current stress, the Cu material exhibited excellent resistance to EM properties, but a passivated SiNx crack was observed due to fast heat conductivity. By applying electrical stress on the gate and drain for 5 × 104 s, the power-law time dependency of the threshold voltage shift (ΔVt) indicated that the defective state creation dominated the TFT device's instability. The presence of drain stress increased the overall ΔVt because the high longitudinal field induced impact ionization and then, enhanced hot-carrier-induced electron trapping within the gate SiNx dielectric. An annealing effect prompted a stressed a-Si:H TFT back to virgin status. This study proposes better ΔVt stability and excellent resistance against electron-migration in a Cu gate device which can be considered as a candidate for a transmission line on prolonged TFT applications.

  10. [Treatment of nontumoral portal vein thrombosis in cirrhosis].

    PubMed

    Bañares, Rafael; Catalina, María-Vega

    2014-07-01

    Portal vein thrombosis in cirrhosis is a relatively common complication associated with the presence of an accompanying prothrombotic phenotype of advanced cirrhosis. The consequences of portal vein thrombosis are relevant because it can be associated with impaired hepatic function, might contraindicate hepatic transplantation and could increase morbidity in the surgical procedure. There is controversy concerning the most effective treatment of portal vein thrombosis, which is based on information that is seldom robust and whose primary objective is to achieve a return to vessel patency. Various studies have suggested that starting anticoagulation therapy early is associated with portal vein repatency more frequently than without treatment and has a low rate of complications. There are no proven data on the type of anticoagulant (low-molecular-weight heparins or dicoumarin agents) and the treatment duration. The implementation of TIPS is technically feasible in thrombosis without cavernous transformation and is associated with portal vein recanalization in a significant proportion of cases. Thrombolytic therapy does not appear to present an adequate balance between efficacy and safety; its use is therefore not supported for this indication. The proper definition of treatment for portal vein thrombosis requires properly designed studies to delimit the efficacy and safety of the various alternatives. Copyright © 2014 Elsevier España, S.L. All rights reserved.

  11. [Surgery in portal hypertension. Which patient and which operation?].

    PubMed

    Mercado, M A; Takahashi, T; Rojas, G; Prado, E; Hernández, J; Tielve, M; Orozco, H

    1993-01-01

    A prospective trial of a cohort of patients (N = 94) with portal hypertension and history of bleeding was selected for surgery based on strict clinical and laboratory criteria. All of them were treated with portal blood flow preserving procedures. The following selection criteria were used: good cardiopulmonary function without pulmonary hypertension and good liver function (Child-Pugh A). All patients were operated in an elective fashion and the operations performed were: selective shunts (N = 38) (distal splenorenal and splenocaval), low diameter mesocaval shunts (N = 13) and the esophagogastric devascularization with esophageal transection (Sugiura-Futagawa) (N = 43). Patients were selected for each operation according to their anatomical conditions. Sixty-one of the patients were cirrhotics. Operative mortality was 8% and rebleeding was observed in 5% of the cases. Postoperative encephalopathy was seen in seven patients (three selective shunts, two low diameter mesocaval shunts and two devascularizations). In 13 of 62 patients postoperatively evaluated by means of angiography, portal vein thrombosis was shown (seven selective shunts, two low diameter shunts and four devascularizations). Twenty-two patients with preoperative portal vein thrombosis (and treated with a Sugiura-Futagawa operation) were excluded from postoperative angiographic evaluation. Survival (Kaplan-Meier) was 85% at 60 months. Portal blood flow preserving procedures are the treatment of choice for patients with hemorrhagic portal hypertension and good liver function. The kind of operation is selected according to the individual anatomical status of the patient.

  12. Interfractional trend analysis of dose differences based on 2D transit portal dosimetry

    NASA Astrophysics Data System (ADS)

    Persoon, L. C. G. G.; Nijsten, S. M. J. J. G.; Wilbrink, F. J.; Podesta, M.; Snaith, J. A. D.; Lustberg, T.; van Elmpt, W. J. C.; van Gils, F.; Verhaegen, F.

    2012-10-01

    Dose delivery of a radiotherapy treatment can be influenced by a number of factors. It has been demonstrated that the electronic portal imaging device (EPID) is valuable for transit portal dosimetry verification. Patient related dose differences can emerge at any time during treatment and can be categorized in two types: (1) systematic—appearing repeatedly, (2) random—appearing sporadically during treatment. The aim of this study is to investigate how systematic and random information appears in 2D transit dose distributions measured in the EPID plane over the entire course of a treatment and how this information can be used to examine interfractional trends, building toward a methodology to support adaptive radiotherapy. To create a trend overview of the interfractional changes in transit dose, the predicted portal dose for the different beams is compared to a measured portal dose using a γ evaluation. For each beam of the delivered fraction, information is extracted from the γ images to differentiate systematic from random dose delivery errors. From the systematic differences of a fraction for a projected anatomical structures, several metrics are extracted like percentage pixels with |γ| > 1. We demonstrate for four example cases the trends and dose difference causes which can be detected with this method. Two sample prostate cases show the occurrence of a random and systematic difference and identify the organ that causes the difference. In a lung cancer case a trend is shown of a rapidly diminishing atelectasis (lung fluid) during the course of treatment, which was detected with this trend analysis method. The final example is a breast cancer case where we show the influence of set-up differences on the 2D transit dose. A method is presented based on 2D portal transit dosimetry to record dose changes throughout the course of treatment, and to allow trend analysis of dose discrepancies. We show in example cases that this method can identify the causes of

  13. Resonant coherent excitation of relativistic Ar 17+ ions channeled in a Si crystal

    NASA Astrophysics Data System (ADS)

    Azuma, T.; Ito, T.; Yamazaki, Y.; Komaki, K.; Sano, M.; Torikoshi, M.; Kitagawa, A.; Takada, E.; Murakami, T.

    1998-02-01

    We observed resonant coherent excitation (RCE) of 1s electron to n=2 states in Ar 17+ through measurements of the survived fraction of 390 MeV/u hydrogen-like Ar 17+ channeled in a Si crystal. We adopted a totally depleted Si surface barrier detector as a target crystal as well as a probe of the energy deposition. The charge state of emerged ions was measured by a combination of a charge separation magnet and a 2D-position sensitive detector. We observed the RCE for planar channeled ions by tilting the target Si crystal from the direction of [1 1 0] axis in the (2 2¯ 0) , (0 0 4) , and (1 1¯ 1) planes. Prominent resonances at tilt angles under the resonance condition were observed. Moreover, each resonance profile is split into several lines due to the l· s interaction and the Stark effect originating in the static crystal field. The energy deposition in the crystal gives the information of the amplitude of the ion trajectory. The resonance peak position, intensity and width in the survived fraction of Ar 17+ reflect the position dependent strength of the crystal field, the RCE and the electron loss probabilities. They are in good accord with our calculation of the transition energy and probability.

  14. Combating the counterfeits with web portal technology

    NASA Astrophysics Data System (ADS)

    Ting, S. L.; Ip, W. H.

    2015-10-01

    Due to the globalisation of counterfeiting activities, the penetration of fake products in open market is growing. So far, the technologies to combat counterfeiting are mostly applied to high-value products (e.g. premium wine and branded handbags); however, in the medium- and low-value products' perspective, there is no secure way for consumers to identify whether the purchased items are genuine or not. To address the counterfeiting problems effectively, a platform for identifying authenticated products and promoting anti-counterfeit activities is very important. The aim of this paper is to design and develop an anti-counterfeit platform which includes two functions: providing customers a secure network to ascertain the genuineness of their purchased product and increasing public awareness of the current counterfeit problems and updated anti-counterfeit solutions. By combining these two functions, it enables public to fight against fake and beware of counterfeit. Results of adopting portal technology in anti-counterfeiting show high accuracy in product checking and improved creditability. This reveals that the applicability and advantage of the proposed methodology are satisfactory.

  15. CircadiOmics: circadian omic web portal.

    PubMed

    Ceglia, Nicholas; Liu, Yu; Chen, Siwei; Agostinelli, Forest; Eckel-Mahan, Kristin; Sassone-Corsi, Paolo; Baldi, Pierre

    2018-06-15

    Circadian rhythms play a fundamental role at all levels of biological organization. Understanding the mechanisms and implications of circadian oscillations continues to be the focus of intense research. However, there has been no comprehensive and integrated way for accessing and mining all circadian omic datasets. The latest release of CircadiOmics (http://circadiomics.ics.uci.edu) fills this gap for providing the most comprehensive web server for studying circadian data. The newly updated version contains high-throughput 227 omic datasets corresponding to over 74 million measurements sampled over 24 h cycles. Users can visualize and compare oscillatory trajectories across species, tissues and conditions. Periodicity statistics (e.g. period, amplitude, phase, P-value, q-value etc.) obtained from BIO_CYCLE and other methods are provided for all samples in the repository and can easily be downloaded in the form of publication-ready figures and tables. New features and substantial improvements in performance and data volume make CircadiOmics a powerful web portal for integrated analysis of circadian omic data.

  16. DESM: portal for microbial knowledge exploration systems.

    PubMed

    Salhi, Adil; Essack, Magbubah; Radovanovic, Aleksandar; Marchand, Benoit; Bougouffa, Salim; Antunes, Andre; Simoes, Marta Filipa; Lafi, Feras F; Motwalli, Olaa A; Bokhari, Ameerah; Malas, Tariq; Amoudi, Soha Al; Othum, Ghofran; Allam, Intikhab; Mineta, Katsuhiko; Gao, Xin; Hoehndorf, Robert; C Archer, John A; Gojobori, Takashi; Bajic, Vladimir B

    2016-01-04

    Microorganisms produce an enormous variety of chemical compounds. It is of general interest for microbiology and biotechnology researchers to have means to explore information about molecular and genetic basis of functioning of different microorganisms and their ability for bioproduction. To enable such exploration, we compiled 45 topic-specific knowledgebases (KBs) accessible through DESM portal (www.cbrc.kaust.edu.sa/desm). The KBs contain information derived through text-mining of PubMed information and complemented by information data-mined from various other resources (e.g. ChEBI, Entrez Gene, GO, KOBAS, KEGG, UniPathways, BioGrid). All PubMed records were indexed using 4,538,278 concepts from 29 dictionaries, with 1 638 986 records utilized in KBs. Concepts used are normalized whenever possible. Most of the KBs focus on a particular type of microbial activity, such as production of biocatalysts or nutraceuticals. Others are focused on specific categories of microorganisms, e.g. streptomyces or cyanobacteria. KBs are all structured in a uniform manner and have a standardized user interface. Information exploration is enabled through various searches. Users can explore statistically most significant concepts or pairs of concepts, generate hypotheses, create interactive networks of associated concepts and export results. We believe DESM will be a useful complement to the existing resources to benefit microbiology and biotechnology research. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Knowledge portal for Six Sigma DMAIC process

    NASA Astrophysics Data System (ADS)

    ThanhDat, N.; Claudiu, K. V.; Zobia, R.; Lobont, Lucian

    2016-08-01

    Knowledge plays a crucial role in success of DMAIC (Define, Measure, Analysis, Improve, and Control) execution. It is therefore necessary to share and renew the knowledge. Yet, one problem arising is how to create a place where knowledge are collected and shared effectively. We believe that Knowledge Portal (KP) is an important solution for the problem. In this article, the works concerning with requirements and functionalities for KP are first reviewed. Afterwards, a procedure with necessary tools to develop and implement a KP for DMAIC (KPD) is proposed. Particularly, KPD is built on the basis of free and open-source content and learning management systems, and Ontology Engineering. In order to structure and store knowledge, tools such as Protégé, OWL, as well as OWL-RDF Parsers are used. A Knowledge Reasoner module is developed in PHP language, ARC2, MySQL and SPARQL endpoint for the purpose of querying and inferring knowledge available from Ontologies. In order to validate the availability of the procedure, a KPD is built with the proposed functionalities and tools. The authors find that the KPD benefits an organization in constructing Web sites by itself with simple steps of implementation and low initial costs. It creates a space of knowledge exchange and supports effectively collecting DMAIC reports as well as sharing knowledge created. The authors’ evaluation result shows that DMAIC knowledge is found exactly with a high success rate and a good level of response time of queries.

  18. SU-F-J-26: Performance of 2.5MV Portal Imaging in Comparison with KV X-Ray and 6MV and Flattening-Filter-Free 6MV Portal Imaging

    SciTech Connect

    Duan, J; Yang, Y; Faught, A

    Purpose: To assess image quality and imaging dose of 2.5MV electronic portal imaging in comparison to kV imaging and 6MV and Flattening-Filter-Free 6MV (6MVFFF) portal imaging using a DMI imager. Methods: Quantitative assessment of image quality was performed with Leeds and Las Vegas test phantoms in conjunction with qualitative evaluation of clinical patient images for kV imaging and 2.5MV, 6MV and 6MVFFF portal imaging. High and low contrast resolutions were evaluated and imaging doses were measured using these x-rays. Phantom test was performed both in air and in solid water. Clinical patient portal images were also reviewed and qualitatively assessedmore » for these three imaging MV energies. Results: Among the 28 objects in Las Vegas phantom, 16, 17 and 26 of them were resolved using Low Dose technique and 18, 22 and 26 were resolved using High Quality technique with 6MV, 6MVFFF and 2.5MV, respectively. The number of Leeds low contrast objects resolved by 6MV, 6MFFFF and 2.5MV was 6, 15 and 18 with Low Dose technique and 14, 17 and 18 with High Quality technique, respectively. When the test phantoms were embedded in 20cm thick solid water, the results were noticeably affected, but the performance of 2.5MV was still substantially better than 6MV and 6MVFFF. Imaging dose with 2.5MV measured at 10 cm depth was about half of that with 6MV or 6MVFFF. Clinical patient portal images were reviewed and qualitatively assessed for different sites including brain, head-and-neck, chest and pelvis. 2.5MV imaging provided more details and substantially higher contrast. Conclusion: While portal imaging with 6MVFFF provides noticeably better image quality than that with 6MV, the performance of 2.5MV portal imaging is substantially better than both 6MV and 6MVFFF in terms of high and low contrast resolutions as well as lower imaging dose. 2.5MV imaging provides near kV imaging quality.« less

  19. Effects of the c-Si/a-SiO2 interfacial atomic structure on its band alignment: an ab initio study.

    PubMed

    Zheng, Fan; Pham, Hieu H; Wang, Lin-Wang

    2017-12-13

    The crystalline-Si/amorphous-SiO 2 (c-Si/a-SiO 2 ) interface is an important system used in many applications, ranging from transistors to solar cells. The transition region of the c-Si/a-SiO 2 interface plays a critical role in determining the band alignment between the two regions. However, the question of how this interface band offset is affected by the transition region thickness and its local atomic arrangement is yet to be fully investigated. Here, by controlling the parameters of the classical Monte Carlo bond switching algorithm, we have generated the atomic structures of the interfaces with various thicknesses, as well as containing Si at different oxidation states. A hybrid functional method, as shown by our calculations to reproduce the GW and experimental results for bulk Si and SiO 2 , was used to calculate the electronic structure of the heterojunction. This allowed us to study the correlation between the interface band characterization and its atomic structures. We found that although the systems with different thicknesses showed quite different atomic structures near the transition region, the calculated band offset tended to be the same, unaffected by the details of the interfacial structure. Our band offset calculation agrees well with the experimental measurements. This robustness of the interfacial electronic structure to its interfacial atomic details could be another reason for the success of the c-Si/a-SiO 2 interface in Si-based electronic applications. Nevertheless, when a reactive force field is used to generate the a-SiO 2 and c-Si/a-SiO 2 interfaces, the band offset significantly deviates from the experimental values by about 1 eV.

  20. Effects of the c-Si/a-SiO 2 interfacial atomic structure on its band alignment: an ab initio study

    SciTech Connect

    Zheng, Fan; Pham, Hieu H.; Wang, Lin-Wang

    The crystalline-Si/amorphous-SiO 2 (c-Si/a-SiO 2) interface is an important system used in many applications, ranging from transistors to solar cells. The transition region of the c-Si/a-SiO 2 interface plays a critical role in determining the band alignment between the two regions. However, the question of how this interface band offset is affected by the transition region thickness and its local atomic arrangement is yet to be fully investigated. Here in this study, by controlling the parameters of the classical Monte Carlo bond switching algorithm, we have generated the atomic structures of the interfaces with various thicknesses, as well as containingmore » Si at different oxidation states. A hybrid functional method, as shown by our calculations to reproduce the GW and experimental results for bulk Si and SiO 2, was used to calculate the electronic structure of the heterojunction. This allowed us to study the correlation between the interface band characterization and its atomic structures. We found that although the systems with different thicknesses showed quite different atomic structures near the transition region, the calculated band offset tended to be the same, unaffected by the details of the interfacial structure. Our band offset calculation agrees well with the experimental measurements. This robustness of the interfacial electronic structure to its interfacial atomic details could be another reason for the success of the c-Si/a-SiO 2 interface in Si-based electronic applications. Nevertheless, when a reactive force field is used to generate the a-SiO 2 and c-Si/a-SiO 2 interfaces, the band offset significantly deviates from the experimental values by about 1 eV« less