Sample records for advanced in-vessel retention

  1. In-vessel tritium retention and removal in ITER

    NASA Astrophysics Data System (ADS)

    Federici, G.; Anderl, R. A.; Andrew, P.; Brooks, J. N.; Causey, R. A.; Coad, J. P.; Cowgill, D.; Doerner, R. P.; Haasz, A. A.; Janeschitz, G.; Jacob, W.; Longhurst, G. R.; Nygren, R.; Peacock, A.; Pick, M. A.; Philipps, V.; Roth, J.; Skinner, C. H.; Wampler, W. R.

    Tritium retention inside the vacuum vessel has emerged as a potentially serious constraint in the operation of the International Thermonuclear Experimental Reactor (ITER). In this paper we review recent tokamak and laboratory data on hydrogen, deuterium and tritium retention for materials and conditions which are of direct relevance to the design of ITER. These data, together with significant advances in understanding the underlying physics, provide the basis for modelling predictions of the tritium inventory in ITER. We present the derivation, and discuss the results, of current predictions both in terms of implantation and codeposition rates, and critically discuss their uncertainties and sensitivity to important design and operation parameters such as the plasma edge conditions, the surface temperature, the presence of mixed-materials, etc. These analyses are consistent with recent tokamak findings and show that codeposition of tritium occurs on the divertor surfaces primarily with carbon eroded from a limited area of the divertor near the strike zones. This issue remains an area of serious concern for ITER. The calculated codeposition rates for ITER are relatively high and the in-vessel tritium inventory limit could be reached, under worst assumptions, in approximately a week of continuous operation. We discuss the implications of these estimates on the design, operation and safety of ITER and present a strategy for resolving the issues. We conclude that as long as carbon is used in ITER - and more generically in any other next-step experimental fusion facility fuelled with tritium - the efficient control and removal of the codeposited tritium is essential. There is a critical need to develop and test in situ cleaning techniques and procedures that are beyond the current experience of present-day tokamaks. We review some of the principal methods that are being investigated and tested, in conjunction with the R&D work still required to extrapolate their

  2. Lymphatic involvement in the histopathogenesis of mucous retention cyst.

    PubMed

    Kundu, Sukalyan; Cheng, Jun; Maruyama, Satoshi; Suzuki, Makoto; Kawashima, Hiroyuki; Saku, Takashi

    2007-01-01

    Mucous retention cyst results from extravasation of saliva. Our intent was to study the role of lymphatics in its pathogenesis. Twenty-three surgical specimens of mucous retention cyst of the lip were examined for involvement of lymphatic vessels by a comparative immunohistochemical demonstration of lymphatic and blood vascular endothelial cells, as well as lymphatic and salivary contents. Mucous retention cysts were histopathologically classified into three stages: early, intermediate, and advanced. In the early stage, there was diffuse extravasation of mucous material in the interstitium of the lamina propria or the submucosal layer of the oral mucosa. In the intermediate stage, lymphatics, which were clearly revealed and immunohistochemically distinguished from blood vessels by monoclonal antibody D2-40, were dilated and finally ruptured, leaving fragments of lymphatic walls in the periphery of mucous pools. In the advanced stage, thick cyst walls of granulation tissue were formed around mucous retention. Lymphatics were no longer involved in the granulation tissue wall, which was actively driven by blood vessel formation. The results suggest that the lymphatic rupture seems to contribute to the enlargement in the pathogenesis of mucous retention cyst.

  3. Toward a Mechanistic Source Term in Advanced Reactors: Characterization of Radionuclide Transport and Retention in a Sodium Cooled Fast Reactor

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brunett, Acacia J.; Bucknor, Matthew; Grabaskas, David

    A vital component of the U.S. reactor licensing process is an integrated safety analysis in which a source term representing the release of radionuclides during normal operation and accident sequences is analyzed. Historically, source term analyses have utilized bounding, deterministic assumptions regarding radionuclide release. However, advancements in technical capabilities and the knowledge state have enabled the development of more realistic and best-estimate retention and release models such that a mechanistic source term assessment can be expected to be a required component of future licensing of advanced reactors. Recently, as part of a Regulatory Technology Development Plan effort for sodium cooledmore » fast reactors (SFRs), Argonne National Laboratory has investigated the current state of knowledge of potential source terms in an SFR via an extensive review of previous domestic experiments, accidents, and operation. As part of this work, the significant sources and transport processes of radionuclides in an SFR have been identified and characterized. This effort examines all stages of release and source term evolution, beginning with release from the fuel pin and ending with retention in containment. Radionuclide sources considered in this effort include releases originating both in-vessel (e.g. in-core fuel, primary sodium, cover gas cleanup system, etc.) and ex-vessel (e.g. spent fuel storage, handling, and movement). Releases resulting from a primary sodium fire are also considered as a potential source. For each release group, dominant transport phenomena are identified and qualitatively discussed. The key product of this effort was the development of concise, inclusive diagrams that illustrate the release and retention mechanisms at a high level, where unique schematics have been developed for in-vessel, ex-vessel and sodium fire releases. This review effort has also found that despite the substantial range of phenomena affecting radionuclide

  4. In-Vessel Tritium Retention and Removal in ITER-FEAT

    NASA Astrophysics Data System (ADS)

    Federici, G.; Brooks, J. N.; Iseli, M.; Wu, C. H.

    Erosion of the divertor and first-wall plasma-facing components, tritium uptake in the re-deposited films, and direct implantation in the armour material surfaces surrounding the plasma, represent crucial physical issues that affect the design of future fusion devices. In this paper we present the derivation, and discuss the results, of current predictions of tritium inventory in ITER-FEAT due to co-deposition and implantation and their attendant uncertainties. The current armour materials proposed for ITER-FEAT are beryllium on the first-wall, carbon-fibre-composites on the divertor plate near the separatrix strike points, to withstand the high thermal loads expected during off-normal events, e.g., disruptions, and tungsten elsewhere in the divertor. Tritium co-deposition with chemically eroded carbon in the divertor, and possibly with some Be eroded from the first-wall, is expected to represent the dominant mechanism of in-vessel tritium retention in ITER-FEAT. This demands efficient in-situ methods of mitigation and retrieval to avoid frequent outages due to the reaching of precautionary operating limits set by safety considerations (e.g., ˜350 g of in-vessel co-deposited tritium) and for fuel economy reasons. Priority areas where further R&D work is required to narrow the remaining uncertainties are also briefly discussed.

  5. Recent advances in lightweight, filament-wound composite pressure vessel technology

    NASA Technical Reports Server (NTRS)

    Lark, R. F.

    1977-01-01

    A review of recent advances is presented for lightweight, high performance composite pressure vessel technology that covers the areas of design concepts, fabrication procedures, applications, and performance of vessels subjected to single cycle burst and cyclic fatigue loading. Filament wound fiber/epoxy composite vessels were made from S glass, graphite, and Kevlar 49 fibers and were equipped with both structural and nonstructural liners. Pressure vessels structural efficiencies were attained which represented weight savings, using different liners, of 40 to 60 percent over all titanium pressure vessels. Significant findings in each area are summarized.

  6. Recent advances in lightweight, filament-wound composite pressure vessel technology

    NASA Technical Reports Server (NTRS)

    Lark, R. F.

    1977-01-01

    A review of recent advances is presented for lightweight, high-performance composite pressure vessel technology that covers the areas of design concepts, fabrication procedures, applications, and performance of vessels subjected to single-cycle burst and cyclic fatigue loading. Filament-wound fiber/epoxy composite vessels were made from S-glass, graphite, and Kevlar 49 fibers and were equipped with both structural and nonstructural liners. Pressure vessel structural efficiencies were attained which represented weight savings, using different liners, of 40 to 60 percent over all-titanium pressure vessels. Significant findings in each area are summarized including data from current NASA-Lewis Research Center contractual and in-house programs.

  7. Large-scale testing of in-vessel debris cooling through external flooding of the reactor pressure vessel in the CYBL facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chu, T.Y.; Bentz, J.H.; Bergeron, K.D.

    1994-04-01

    The possibility of achieving in-vessel core retention by flooding the reactor cavity, or the ``flooded cavity``, is an accident management concept currently under consideration for advanced light water reactors (ALWR), as well as for existing light water reactors (LWR). The CYBL (CYlindrical BoiLing) facility is a facility specifically designed to perform large-scale confirmatory testing of the flooded cavity concept. CYBL has a tank-within-a-tank design; the inner 3.7 m diameter tank simulates the reactor vessel, and the outer tank simulates the reactor cavity. The energy deposition on the bottom head is simulated with an array of radiant heaters. The array canmore » deliver a tailored heat flux distribution corresponding to that resulting from core melt convection. The present paper provides a detailed description of the capabilities of the facility, as well as results of recent experiments with heat flux in the range of interest to those required for in-vessel retention in typical ALWRs. The paper concludes with a discussion of other experiments for the flooded cavity applications.« less

  8. In-vessel melt retention as a severe accident management strategy for the Loviisa Nuclear Power Plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kymaelaeinen, O.; Tuomisto, H.; Theofanous, T.G.

    1997-02-01

    The concept of lower head coolability and in-vessel retention of corium has been approved as a basic element of the severe accident management strategy for IVO`s Loviisa Plant (VVER-440) in Finland. The selected approach takes advantage of the unique features of the plant such as low power density, reactor pressure vessel without penetrations at the bottom and ice-condenser containment which ensures flooded cavity in all risk significant sequences. The thermal analyses, which are supported by experimental program, demonstrate that in Loviisa the molten corium on the lower head of the reactor vessel is coolable externally with wide margins. This papermore » summarizes the approach and the plant modifications being implemented. During the approval process some technical concerns were raised, particularly with regard to thermal loadings caused by contact of cool cavity water and hot corium with the reactor vessel. Resolution of these concerns is also discussed.« less

  9. In-vessel coolability and retention of a core melt. Volume 1

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Theofanous, T.G.; Liu, C.; Additon, S.

    1996-10-01

    The efficacy of external flooding of a reactor vessel as a severe accident management strategy is assessed for an AP600-like reactor design. The overall approach is based on the Risk Oriented Accident Analysis Methodology (ROAAM), and the assessment includes consideration of bounding scenarios and sensitivity studies, as well as arbitrary parametric evaluations that allow the delineation of the failure boundaries. Quantification of the input parameters is carried out for an AP600-like design, and the results of the assessment demonstrate that lower head failure is physically unreasonable. Use of this conclusion for any specific application is subject to verifying the requiredmore » reliability of the depressurization and cavity-flooding systems, and to showing the appropriateness (in relation to the database presented here, or by further testing as necessary) of the thermal insulation design and of the external surface properties of the lower head, including any applicable coatings. The AP600 is particularly favorable to in-vessel retention. Some ideas to enhance the assessment basis as well as performance in this respect, for applications to larger and/or higher power density reactors are also provided.« less

  10. In-vessel coolability and retention of a core melt. Volume 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Theofanous, T.G.; Liu, C.; Additon, S.

    1996-10-01

    The efficacy of external flooding of a reactor vessel as a severe accident management strategy is assessed for an AP600-like reactor design. The overall approach is based on the Risk Oriented Accident Analysis Methodology (ROAAM), and the assessment includes consideration of bounding scenarios and sensitivity studies, as well as arbitrary parametric evaluations that allow the delineation of the failure boundaries. Quantification of the input parameters is carried out for an AP600-like design, and the results of the assessment demonstrate that lower head failure is physically unreasonable. Use of this conclusion for any specific application is subject to verifying the requiredmore » reliability of the depressurization and cavity-flooding systems, and to showing the appropriateness (in relation to the database presented here, or by further testing as necessary) of the thermal insulation design and of the external surface properties of the lower head, including any applicable coatings. The AP600 is particularly favorable to in-vessel retention. Some ideas to enhance the assessment basis as well as performance in this respect, for applications to larger and/or higher power density reactors are also provided.« less

  11. Advancing the science of recruitment and retention of ethnically diverse populations.

    PubMed

    Nápoles, Anna M; Chadiha, Letha A

    2011-06-01

    We highlight several critical challenges that must be addressed to accelerate the advancement of the science on recruitment and retention of ethnically diverse older adults into health research. These include the relative lack of attention by researchers to methodological issues related to recruitment and retention of ethnically diverse populations and the inadequacy of funding to advance systematically this field. We describe strategies used by the Resource Centers on Minority Aging Research and other National Institute of Aging-funded programs to advance the science of recruitment of ethnically diverse older adults. Finally, we propose a set of broad recommendations designed to generate a body of evidence on successful methods of recruitment and retention of ethnically diverse populations in health research. To eliminate health disparities and better understand aging processes in ethnically diverse populations, much more research is needed on effective strategies for increasing minority enrollment in health research. Comparative effectiveness research on more intensive recruitment and retention methods, which are often needed for including diverse populations, will require dedicated funding and concerted efforts by investigators.

  12. 33 CFR 401.79 - Advance notice of arrival, vessels requiring inspection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., vessels requiring inspection. 401.79 Section 401.79 Navigation and Navigable Waters SAINT LAWRENCE SEAWAY... Reports § 401.79 Advance notice of arrival, vessels requiring inspection. Every vessel shall provide at... reinspection of the ship is required. [70 FR 12973, Mar. 17, 2005] ...

  13. The pathophysiological mechanism of fluid retention in advanced cancer patients treated with docetaxel, but not receiving corticosteroid comedication.

    PubMed

    Béhar, A; Pujade-Lauraine, E; Maurel, A; Brun, M D; Chauvin, F F; Feuilhade de Chauvin, F; Oulid-Aissa, D; Hille, D

    1997-06-01

    Fluid retention is a phenomenon associated with taxoids. The principal objective of this study was to investigate the pathophysiological mechanism of docetaxel-induced fluid retention in advanced cancer patients. Docetaxel was administered as a 1 h intravenous infusion every 3 weeks, for at least 4-6 consecutive cycles, to patients with advanced breast (n = 21) or ovarian (n = 3) carcinoma, who had received previous chemotherapy, 21 for advanced disease. Phase II clinical trials have shown that 5 day corticosteroid comedication, starting 1 day before docetaxel infusion, significantly reduces the incidence and severity of fluid retention. This prophylactic corticosteroid regimen is currently recommended for patients receiving docetaxel but was not permitted in this study because of its possible interference with the underlying pathophysiology of the fluid retention. Fluid retention occurred in 21 of the 24 patients but was mainly mild to moderate, with only five patients experiencing severe fluid retention. Eighteen patients received symptomatic flavonoid treatment, commonly prescribed after the last cycle. Specific investigations for fluid retention confirmed a relationship between cumulative docetaxel dose and development of fluid retention. Capillary filtration test analysis showed a two-step process for fluid retention generation, with progressive congestion of the interstitial space by proteins and water starting between the second and the fourth cycle, followed by insufficient lymphatic drainage. A vascular protector such as micronized diosmine hesperidine with recommended corticosteroid premedication and benzopyrones may be useful in preventing and treating docetaxel-induced fluid retention.

  14. The Employment Retention and Advancement Project: Paths to Advancement for Single Parents

    ERIC Educational Resources Information Center

    Miller, Cynthia; Deitch, Victoria; Hill, Aaron

    2010-01-01

    Between 2000 and 2003, the Employment Retention and Advancement (ERA) project identified and implemented a diverse set of innovative models designed to promote employment stability and wage or earnings progression among low-income individuals, mostly current or former welfare recipients. The project's goal was to determine which strategies could…

  15. CHF Enhancement by Vessel Coating for External Reactor Vessel Cooling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fan-Bill Cheung; Joy L. Rempe

    2004-06-01

    In-vessel retention (IVR) is a key severe accident management (SAM) strategy that has been adopted by some operating nuclear power plants and advanced light water reactors (ALWRs). One viable means for IVR is the method of external reactor vessel cooling (ERVC) by flooding of the reactor cavity during a severe accident. As part of a joint Korean – United States International Nuclear Energy Research Initiative (K-INERI), an experimental study has been conducted to investigate the viability of using an appropriate vessel coating to enhance the critical heat flux (CHF) limits during ERVC. Toward this end, transient quenching and steady-state boilingmore » experiments were performed in the SBLB (Subscale Boundary Layer Boiling) facility at Penn State using test vessels with micro-porous aluminum coatings. Local boiling curves and CHF limits were obtained in these experiments. When compared to the corresponding data without coatings, substantial enhancement in the local CHF limits for the case with surface coatings was observed. Results of the steady state boiling experiments showed that micro-porous aluminum coatings were very durable. Even after many cycles of steady state boiling, the vessel coatings remained rather intact, with no apparent changes in color or structure. Moreover, the heat transfer performance of the coatings was found to be highly desirable with an appreciable CHF enhancement in all locations on the vessel outer surface but with very little effect of aging.« less

  16. The pathophysiological mechanism of fluid retention in advanced cancer patients treated with docetaxel, but not receiving corticosteroid comedication

    PubMed Central

    Béhar, A.; Pujade-Lauraine, E.; Maurel, A.; Brun, M. D.; Lagrue, G.; Feuilhade De Chauvin, F.; Oulid-Aissa, D.; Hille, D.

    1997-01-01

    Aims Fluid retention is a phenomenon associated with taxoids. The principal objective of this study was to investigate the pathophysiological mechanism of docetaxel-induced fluid retention in advanced cancer patients. Methods Docetaxel was administered as a 1 h intravenous infusion every 3 weeks, for at least 4–6 consecutive cycles, to patients with advanced breast (n=21) or ovarian (n=3) carcinoma, who had received previous chemotherapy, 21 for advanced disease. Phase II clinical trials have shown that 5 day corticosteroid comedication, starting 1 day before docetaxel infusion, significantly reduces the incidence and severity of fluid retention. This prophylactic corticosteroid regimen is currently recommended for patients receiving docetaxel but was not permitted in this study because of its possible interference with the underlying pathophysiology of the fluid retention. Results Fluid retention occurred in 21 of the 24 patients but was mainly mild to moderate, with only five patients experiencing severe fluid retention. Eighteen patients received symptomatic flavonoid treatment, commonly prescribed after the last cycle. Specific investigations for fluid retention confirmed a relationship between cumulative docetaxel dose and development of fluid retention. Capillary filtration test analysis showed a two-step process for fluid retention generation, with progressive congestion of the interstitial space by proteins and water starting between the second and the fourth cycle, followed by insufficient lymphatic drainage. Conclusions A vascular protector such as micronized diosmine hesperidine with recommended corticosteroid premedication and benzopyrones may be useful in preventing and treating docetaxel-induced fluid retention. PMID:9205828

  17. The Employment Retention and Advancement Project. Results from the Texas ERA Site

    ERIC Educational Resources Information Center

    Martinson, Karin; Hendra, Richard

    2006-01-01

    This report presents an assessment of the implementation and the two-year impacts of a program in Texas that aimed to promote job placement, employment retention, and advancement among applicants and recipients to the Temporary Assistance for Needy Families (TANF) program. The program in Texas is part of the Employment Retention and Advancement…

  18. The Employment Retention and Advancement Project: How Effective Are Different Approaches Aiming to Increase Employment Retention and Advancement? Final Impacts for Twelve Models. Executive Summary

    ERIC Educational Resources Information Center

    Hendra, Richard; Dillman, Keri-Nicole; Hamilton, Gayle; Lundquist, Erika; Martinson, Karin; Wavelet, Melissa

    2010-01-01

    This report summarizes the final impact results for the national Employment Retention and Advancement (ERA) project. This project tested, using a random assignment design, the effectiveness of numerous programs intended to promote steady work and career advancement. All the programs targeted current and former welfare recipients and other low-wage…

  19. Advanced Datapresence From A New Generation Of Research Vessels

    NASA Astrophysics Data System (ADS)

    Romsos, C. G.; Nahorniak, J.; Watkins-Brandt, K.; Bailey, D.; Reimers, C.

    2016-02-01

    The design of the next generation Regional Class Research Vessels (RCRV) for the U.S. academic research fleet includes the development of advanced datapresence systems and capabilities. Datapresence is defined here as the real-time transfer of scientific and operational data between vessel and shore, to facilitate shore-based participation in oceanographic expeditions. Datapresent technologies on the RCRVs build upon the demonstrated success of telepresence activities on satellite-connected ships. Specifically, the RCRV datapresence design integrates a broad suite of ocean and meteorological sensors on the vessel into a networked environment with satellite communication access. In addition to enabling operational decisions from shore, these capabilities will bring ocean research to the classroom and local communities, advancing ocean and atmospheric literacy, via dynamic data products that support hands-on exercises and demonstrations of oceanographic and atmospheric processes. The operational requirements of data integration, management, visualization, and user-interaction are being developed and tested now and will be refined over the next 5-6 years during the RCRV construction and transition to operations phases. This presentation will illustrate the RCRV datapresence design and how datapresent technologies will transform these National Science Foundation-owned coastal ships into continuous sampling and data streaming platforms that leverage onshore resources for making efficient scientific and operational decisions.

  20. Americium behaviour in plastic vessels.

    PubMed

    Legarda, F; Herranz, M; Idoeta, R; Abelairas, A

    2010-01-01

    The adsorption of (241)Am dissolved in water in different plastic storage vessels was determined. Three different plastics were investigated with natural and distilled waters and the retention of (241)Am by these plastics was studied. The same was done by varying vessel agitation time, vessel agitation speed, surface/volume ratio of water in the vessels and water pH. Adsorptions were measured to be between 0% and 70%. The adsorption of (241)Am is minimized with no water agitation, with PET or PVC plastics, and by water acidification. Copyright 2009 Elsevier Ltd. All rights reserved.

  1. The Employment Retention and Advancement Project: Paths to Advancement for Single Parents. Executive Summary

    ERIC Educational Resources Information Center

    Miller, Cynthia; Deitch, Victoria; Hill, Aaron

    2010-01-01

    Between 2000 and 2003, the Employment Retention and Advancement (ERA) project identified and implemented a diverse set of innovative models designed to promote employment stability and wage or earnings progression among low-income individuals, mostly current or former welfare recipients. The project's goal was to determine which strategies could…

  2. Workforce Development: Employment Retention and Advancement Under TANF. Technical Paper.

    ERIC Educational Resources Information Center

    Patel, Nisha

    In this report, employment retention and advancement under Temporary Assistance for Needy Families (TANF) was examined by reviewing research findings regarding labor market development since 1996. According to the research, most of those moving from welfare to work have found employment in low-wage jobs and experienced frequent job losses and…

  3. Smooth muscle cell recruitment to lymphatic vessels requires PDGFB and impacts vessel size but not identity.

    PubMed

    Wang, Yixin; Jin, Yi; Mäe, Maarja Andaloussi; Zhang, Yang; Ortsäter, Henrik; Betsholtz, Christer; Mäkinen, Taija; Jakobsson, Lars

    2017-10-01

    Tissue fluid drains through blind-ended lymphatic capillaries, via smooth muscle cell (SMC)-covered collecting vessels into venous circulation. Both defective SMC recruitment to collecting vessels and ectopic recruitment to lymphatic capillaries are thought to contribute to vessel failure, leading to lymphedema. However, mechanisms controlling lymphatic SMC recruitment and its role in vessel maturation are unknown. Here, we demonstrate that platelet-derived growth factor B (PDGFB) regulates lymphatic SMC recruitment in multiple vascular beds. PDGFB is selectively expressed by lymphatic endothelial cells (LECs) of collecting vessels. LEC-specific deletion of Pdgfb prevented SMC recruitment causing dilation and failure of pulsatile contraction of collecting vessels. However, vessel remodelling and identity were unaffected. Unexpectedly, Pdgfb overexpression in LECs did not induce SMC recruitment to capillaries. This was explained by the demonstrated requirement of PDGFB extracellular matrix (ECM) retention for lymphatic SMC recruitment, and the low presence of PDGFB-binding ECM components around lymphatic capillaries. These results demonstrate the requirement of LEC-autonomous PDGFB expression and retention for SMC recruitment to lymphatic vessels, and suggest an ECM-controlled checkpoint that prevents SMC investment of capillaries, which is a common feature in lymphedematous skin. © 2017. Published by The Company of Biologists Ltd.

  4. Recruitment, Advancement and Retention of Women in the Physical Sciences at U.C. Irvine

    NASA Astrophysics Data System (ADS)

    Druffel, E. R.; Smecker-Hane, T.; Kehoe, P.; Bryant, S. V.

    2004-12-01

    Strategies for the recruitment, retention and advancement of women in the physical sciences at U.C. Irvine are presented. The NSF-funded ADVANCE Program has implemented several new initiatives. Among these are new requirements for recruitment committees, participation by school equity advisors, personalized mentoring programs and establishment of senior chairs. Progress towards our goals are reviewed and evaluated. Issues such as dual career couples and the balance between family/personal time and work are also addressed.

  5. The Impact of a Junior Faculty Fellowship Award on Academic Advancement and Retention.

    PubMed

    Connelly, Maureen T; Sullivan, Amy M; Chinchilla, Manuel; Dale, Margaret L; Emans, S Jean; Nadelson, Carol Cooperman; Notman, Malkah Tolpin; Tarbell, Nancy J; Zigler, Corwin M; Shore, Eleanor G

    2017-08-01

    Academic faculty experience barriers to career development and promotion. In 1996, Harvard Medical School (HMS) initiated an intramural junior faculty fellowship to address these obstacles. The authors sought to understand whether receiving a fellowship was associated with more rapid academic promotion and retention. Junior faculty fellowship recipients and all other instructor and assistant professors at HMS between 1996 and 2011 were identified. Using propensity score modeling, the authors created a matched comparison group for the fellowship recipients based on educational background, training, academic rank, department, hospital affiliation, and demographics. Time to promotion and time to leaving were assessed by Kaplan-Meier curves. A total of 622 junior faculty received fellowships. Faculty who received fellowships while instructors (n = 480) had shorter times to promotion to assistant professor (P < .0001) and longer retention times (P < .0001) than matched controls. There were no significant differences in time to promotion for assistant professors who received fellowships (n = 142) compared with matched controls, but assistant professor fellowship recipients were significantly more likely to remain longer on the faculty (P = .0005). Women instructors advanced more quickly than matched controls, while male instructors' rates of promotions did not differ. Fellowships to support junior faculty were associated with shorter times to promotion for instructors and more sustained faculty retention for both instructors and assistant professors. This suggests that relatively small amounts of funding early in faculty careers can play a critical role in supporting academic advancement and retention.

  6. Development of advanced manufacturing technologies for low cost hydrogen storage vessels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Leavitt, Mark; Lam, Patrick

    2014-12-29

    The U.S. Department of Energy (DOE) defined a need for low-cost gaseous hydrogen storage vessels at 700 bar to support cost goals aimed at 500,000 units per year. Existing filament winding processes produce a pressure vessel that is structurally inefficient, requiring more carbon fiber for manufacturing reasons, than would otherwise be necessary. Carbon fiber is the greatest cost driver in building a hydrogen pressure vessel. The objective of this project is to develop new methods for manufacturing Type IV pressure vessels for hydrogen storage with the purpose of lowering the overall product cost through an innovative hybrid process of optimizingmore » composite usage by combining traditional filament winding (FW) and advanced fiber placement (AFP) techniques. A numbers of vessels were manufactured in this project. The latest vessel design passed all the critical tests on the hybrid design per European Commission (EC) 79-2009 standard except the extreme temperature cycle test. The tests passed include burst test, cycle test, accelerated stress rupture test and drop test. It was discovered the location where AFP and FW overlap for load transfer could be weakened during hydraulic cycling at 85°C. To design a vessel that passed these tests, the in-house modeling software was updated to add capability to start and stop fiber layers to simulate the AFP process. The original in-house software was developed for filament winding only. Alternative fiber was also investigated in this project, but the added mass impacted the vessel cost negatively due to the lower performance from the alternative fiber. Overall the project was a success to show the hybrid design is a viable solution to reduce fiber usage, thus driving down the cost of fuel storage vessels. Based on DOE’s baseline vessel size of 147.3L and 91kg, the 129L vessel (scaled to DOE baseline) in this project shows a 32% composite savings and 20% cost savings when comparing Vessel 15 hybrid design and the Quantum

  7. Developing a neonatal workforce: role evolution and retention of advanced neonatal nurse practitioners

    PubMed Central

    Smith, S; Hall, M

    2003-01-01

    Background: Over the past decade more than 120 advanced neonatal nurse practitioners (ANNPs) have graduated from the Southampton based ANNP programme. Objectives: To determine the scope of practice and evolving role of ANNPs and to identify factors that may affect future recruitment and retention. Method: An open ended structured questionnaire on clinical role, working arrangements, retention and attrition, continuing education, and professional development was sent to 95 ANNPs. Results: A response rate of 83% was achieved. There was an attrition rate of 14%, with most ANNPs remaining in their original seconding unit. Factors considered to be important for role satisfaction included a well defined role, working within a team of ANNPs, appropriate remuneration, and evidence of unit support for both role definition and continuing professional development. Conclusions: Although ANNPs are expensive to both train and employ, this evidence suggests that there is a good return on the investment in terms of retention to the unit and the specialty. Their role incorporates many features of advanced nursing practice as well as providing "value added" neonatal care by merging traditional medical and nursing roles and crossing professional boundaries. In 2004 the manpower challenges for neonatal units will be even more acute; these data confirm that there are effective options available but they require long term strategic planning and investment. PMID:12937050

  8. Structural design and stress analysis program for advanced composite filament-wound axisymmetric pressure vessels (COMTANK)

    NASA Technical Reports Server (NTRS)

    Knoell, A. C.

    1972-01-01

    Computer program has been specifically developed to handle, in an efficient and cost effective manner, planar wound pressure vessels fabricated of either boron-epoxy or graphite-epoxy advanced composite materials.

  9. Can Low-Income Single Parents Move up in the Labor Market? Findings from the Employment Retention and Advancement Project. Practitioner Brief

    ERIC Educational Resources Information Center

    Miller, Cynthia; Deitch, Victoria; Hill, Aaron

    2011-01-01

    The Employment Retention and Advancement (ERA) project evaluated strategies to promote employment stability among low-income workers. This practitioner brief examines the work, education, and training patterns of single parents in the ERA project. Three years after entering the study, only one in four single parents had advanced. Most of the…

  10. Nuclear reactor support and seismic restraint with in-vessel core retention cooling features

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Edwards, Tyler A.; Edwards, Michael J.

    A nuclear reactor including a lateral seismic restraint with a vertically oriented pin attached to the lower vessel head and a mating pin socket attached to the floor. Thermally insulating materials are disposed alongside the exterior surface of a lower portion of the reactor pressure vessel including at least the lower vessel head.

  11. New Strategies To Promote Stable Employment and Career Progression: An Introduction to the Employment Retention and Advancement Project.

    ERIC Educational Resources Information Center

    Bloom, Dan; Anderson, Jacquelyn; Wavelet, Melissa; Gardiner, Karen N.; Fishman, Michael E.

    The Employment Retention and Advancement (ERA) project was undertaken to identify effective strategies for helping low-income parents work more steadily and advance in the labor market. The 15 ERA demonstration projects that were operating in nine states (California, Florida, Illinois, Minnesota, New York, Oregon, South Carolina; Tennessee, and…

  12. Wireless, in-vessel neutron monitor for initial core-loading of advanced breeder reactors

    NASA Technical Reports Server (NTRS)

    Delorenzo, J. T.; Kennedy, E. J.; Blalock, T. V.; Rochelle, J. M.; Chiles, M. M.; Valentine, K. H.

    1981-01-01

    An experimental wireless, in-vessel neutron monitor was developed to measure the reactivity of an advanced breeder reactor as the core is loaded for the first time to preclude an accidental critically incident. The environment is liquid sodium at a temperature of approx. 220 C, with negligible gamma or neutron radiation. With ultrasonic transmission of neutron data, no fundamental limitation was observed after tests at 230 C for 2000 h. The neutron sensitivity was approx. 1 count/s-nv, and the potential data transmission rate was approx. 10,000 counts/s.

  13. 50 CFR 635.24 - Commercial retention limits for sharks and swordfish.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 10 2011-10-01 2011-10-01 false Commercial retention limits for sharks... Management Measures § 635.24 Commercial retention limits for sharks and swordfish. The retention limits in... operation and deployment restrictions in § 635.21. (a) Sharks. (1) A person who owns or operates a vessel...

  14. Validating Student Satisfaction Related to Persistence, Academic Performance, Retention and Career Advancement within ODL Perspectives

    ERIC Educational Resources Information Center

    Sembiring, Maximus Gorky

    2015-01-01

    Student satisfaction associated with persistence, academic performance, retention, and its relations to career advancement were examined. It was aimed at measuring service quality (Servqual) dimensions as a foundation of satisfaction and how, in what comportments, they were interrelated. The study was conducted under explanatory-design. Data was…

  15. Fluid Dynamics of Magnetic Nanoparticles in Simulated Blood Vessels

    NASA Astrophysics Data System (ADS)

    Blue, Lauren; Sewell, Mary Kathryn; Brazel, Christopher S.

    2008-11-01

    Magnetic nanoparticles (MNPs) can be used to locally target therapies and offer the benefit of using an AC magnetic field to combine hyperthermia treatment with the triggered release of therapeutic agents. Here, we investigate localization of MNPs in a simulated environment to understand the relationship between magnetic field intensity and bulk fluid dynamics to determine MNP retention in a simulated blood vessel. As MNPs travel through blood vessels, they can be slowed or trapped in a specific area by applying a magnetic field. Magnetic cobalt ferrite nanoparticles were synthesized and labeled with a fluorescent rhodamine tag to visualize patterns in a flow cell, as monitored by a fluorescence microscope. Particle retention was determined as a function of flow rate, concentration, and magnetic field strength. Understanding the relationship between magnetic field intensity, flow behavior and nanoparticle characteristics will aid in the development of therapeutic systems specifically targeted to diseased tissue.

  16. Common pressure vessel battery performance

    NASA Technical Reports Server (NTRS)

    Otzinger, B.

    1978-01-01

    Performance tests run on two common pressure vessel type nickel hydrogen batteries are described and the results presented. The study included: (1) charge retention tests, (2) synchronous eclipse season cycling tests, and (3) temperature differential tests.

  17. Large-scale boiling experiments of the flooded cavity concept for in-vessel core retention

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chu, T.Y.; Slezak, S.E.; Bentz, J.H.

    1994-03-01

    This paper presents results of ex-vessel boiling experiments performed in the CYBL (CYlindrical BoiLing) facility. CYBL is a reactor-scale facility for confirmatory research of the flooded cavity concept for accident management. CYBL has a tank-within-a-tank design; the inner tank simulates the reactor vessel and the outer tank simulates the reactor cavity. Experiments with uniform and edge-peaked heat flux distributions up to 20 W/cm{sup 2} across the vessel bottom were performed. Boiling outside the reactor vessel was found to be subcooled nucleate boiling. The subcooling is mainly due to the gravity head which results from flooding the sides of the reactormore » vessel. The boiling process exhibits a cyclic pattern with four distinct phases: direct liquid/solid contact, bubble nucleation and growth, coalescence, and vapor mass dispersion (ejection). The results suggest that under prototypic heat load and heat flux distributions, the flooded cavity in a passive pressurized water reactor like the AP-600 should be capable of cooling the reactor pressure vessel in the central region of the lower head that is addressed by these tests.« less

  18. Explosive vessel for coupling dynamic experiments to the X-ray beam at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Owens, Charles; Sanchez, Nathaniel; Sorensen, Christian; Jensen, Brian

    2017-06-01

    Recent experiments at the Advanced Photon Source have been successful in coupling gun systems to the synchrotron to take advantage of the advanced X-ray diagnostics available including X-ray diffraction and X-ray phase contrast imaging (PCI) to examine matter at extreme conditions. There are many experiments that require explosive loading capabilities, e.g. detonator and initiator dynamics, small angle X-ray scattering (SAXS), ejecta formation, and explosively driven flyer experiments. The current work highlights a new explosive vessel that was designed specifically for use at a synchrotron facility with requirements to confine up to 15 grams of explosives (TNT equivalent), couple the vessel to the X-ray beam line, and reliably position samples remotely. A description of the system and capability will be provided along with the results from qualification testing to bring the system into service (LA-UR-17-21381).

  19. From Lipid Retention to Immune-Mediate Inflammation and Associated Angiogenesis in the Pathogenesis of Atherosclerosis.

    PubMed

    Usman, Ammara; Ribatti, Domenico; Sadat, Umar; Gillard, Jonathan H

    2015-08-26

    Atherosclerosis is a leading cause of mortality and long-term morbidity worldwide. It is a lipoprotein-driven disease that leads to plaque formation at focal areas in the arterial blood vessels through intimal inflammation, necrosis, fibrosis, and calcification. Adventitial and intimal angiogenesis contributes to the progression of intimal hyperplasia and the development of a necrotic core. The volatile nature of an atheromatous plaque is responsible for approximately 60% of symptomatic carotid artery diseases and about 75% of acute coronary events. In this review the pathogenesis of atherosclerosis is discussed from the initial step of lipid retention to advanced stages of immune-mediate inflammation and associated angiogenesis. Mechanisms of plaque rupture are also discussed.

  20. Advanced Image Enhancement Method for Distant Vessels and Structures in Capsule Endoscopy

    PubMed Central

    Pedersen, Marius

    2017-01-01

    This paper proposes an advanced method for contrast enhancement of capsule endoscopic images, with the main objective to obtain sufficient information about the vessels and structures in more distant (or darker) parts of capsule endoscopic images. The proposed method (PM) combines two algorithms for the enhancement of darker and brighter areas of capsule endoscopic images, respectively. The half-unit weighted-bilinear algorithm (HWB) proposed in our previous work is used to enhance darker areas according to the darker map content of its HSV's component V. Enhancement of brighter areas is achieved thanks to the novel threshold weighted-bilinear algorithm (TWB) developed to avoid overexposure and enlargement of specular highlight spots while preserving the hue, in such areas. The TWB performs enhancement operations following a gradual increment of the brightness of the brighter map content of its HSV's component V. In other words, the TWB decreases its averaged weights as the intensity content of the component V increases. Extensive experimental demonstrations were conducted, and, based on evaluation of the reference and PM enhanced images, a gastroenterologist (Ø.H.) concluded that the PM enhanced images were the best ones based on the information about the vessels, contrast in the images, and the view or visibility of the structures in more distant parts of the capsule endoscopy images. PMID:29225668

  1. Use It or Lose It: Advances in Our Understanding of Terrestrial Nitrogen Retention and Loss (Invited)

    NASA Astrophysics Data System (ADS)

    Silver, W. L.; Yang, W. H.

    2013-12-01

    Understanding of the terrestrial nitrogen (N) cycle has grown over the last decade to include a variety of pathways that have the potential to either retain N in the ecosystem or result in losses to the atmosphere or groundwater. Early work has described the mechanics of these N transformations, but the relevance of these processes to ecosystem, regional, or global scale N cycling has not been well quantified. In this study, we review advances in our understanding of the terrestrial N cycle, and focus on three pathways with particular relevance to N retention and loss: dissimilatory nitrate and nitrite reduction to ammonium (DNRA), anaerobic ammonium oxidation (annamox), and anaerobic ammonium oxidation coupled to iron reduction (Feammox). We discuss the role of these processes in the microbial N economy (sensu Burgin et al. 2011) of the terrestrial N cycle, the environmental and ecological constraints, and relationships with other key biogeochemical cycles. We also discuss recent advances in analytical approaches that have improved our ability to detect these and related N fluxes in terrestrial ecosystems. Finally, we present a scaling exercise that identifies the potential importance of these pathways for N retention and loss across a range of spatial and temporal scales, and discuss their significance in terms of N limitation to net primary productivity, N leaching to groundwater, and the release of reactive N gases to the atmosphere.

  2. Simplified tools for measuring retention in care in antiretroviral treatment program in Ethiopia: cohort and current retention in care.

    PubMed

    Assefa, Yibeltal; Worku, Alemayehu; Wouters, Edwin; Koole, Olivier; Haile Mariam, Damen; Van Damme, Wim

    2012-01-01

    Patient retention in care is a critical challenge for antiretroviral treatment programs. This is mainly because retention in care is related to adherence to treatment and patient survival. It is therefore imperative that health facilities and programs measure patient retention in care. However, the currently available tools, such as Kaplan Meier, for measuring retention in care have a lot of practical limitations. The objective of this study was to develop simplified tools for measuring retention in care. Retrospective cohort data were collected from patient registers in nine health facilities in Ethiopia. Retention in care was the primary outcome for the study. Tools were developed to measure "current retention" in care during a specific period of time for a specific "ART-age group" and "cohort retention" in care among patients who were followed for the last "Y" number of years on ART. "Probability of retention" based on the tool for "cohort retention" in care was compared with "probability of retention" based on Kaplan Meier. We found that the new tools enable to measure "current retention" and "cohort retention" in care. We also found that the tools were easy to use and did not require advanced statistical skills. Both "current retention" and "cohort retention" are lower among patients in the first two "ART-age groups" and "ART-age cohorts" than in subsequent "ART-age groups" and "ART-age cohorts". The "probability of retention" based on the new tools were found to be similar to the "probability of retention" based on Kaplan Meier. The simplified tools for "current retention" and "cohort retention" will enable practitioners and program managers to measure and monitor rates of retention in care easily and appropriately. We therefore recommend that health facilities and programs start to use these tools in their efforts to improve retention in care and patient outcomes.

  3. Changes in cross-sectional area of pulmonary vessels on chest computed tomography after chemotherapy in patients with advanced non-squamous non-small-cell lung cancer.

    PubMed

    Karayama, Masato; Inui, Naoki; Kusagaya, Hideki; Suzuki, Seiichiro; Inoue, Yusuke; Enomoto, Noriyuki; Fujisawa, Tomoyuki; Nakamura, Yutaro; Suda, Takafumi

    2016-05-01

    Chemotherapy is associated with a risk of vascular damage. Novel anti-angiogenic agents, which can directly affect tumor angiogenesis, are increasingly being used. However, the effects of these agents on normal vasculature are not well understood. Here, we evaluated the effects of chemotherapy in general, and the anti-angiogenic agent bevacizumab, more specifically, on the pulmonary vasculature in patients with advanced non-squamous non-small-cell lung cancer (NSCLC). For this, we used the cross-sectional area of pulmonary vessels (CSA), which is an easily measurable indicator of small pulmonary vasculature on non-contrast chest computed tomography (CT). We retrospectively reviewed CT scans of the lungs of 75 chemo-naïve patients with advanced non-squamous NSCLC, for measurement of CSA, before and after first-line platinum-based chemotherapy, using a semi-automatic image-processing program. Measured vessels were classified in two groups: small vessels with CSA <5 mm(2) and large vessels with CSA between 5 and 10 mm(2). The CSAs for each group of vessels were calculated and summed separately, and expressed as a percentage of the total lung area (%CSA<5 and %CSA5-10). Chemotherapy was associated with a selective decrease in small-diameter vessels, with a significant decrease in %CSA<5, but not %CSA5-10. When comparing chemotherapy with bevacizumab (n = 38) and without bevacizumab (n = 37), there was no significant difference in the reduction of %CSA<5. Platinum-based chemotherapy might induce small pulmonary vascular damage. Use of bevacizumab does not enhance the reduction in area of pulmonary vessels.

  4. Jam proof closure assembly for lidded pressure vessels

    DOEpatents

    Cioletti, Olisse C.

    1992-01-01

    An expendable closure assembly is provided for use (in multiple units) with a lockable pressure vessel cover along its rim, such as of an autoclave. This assembly is suited to variable compressive contact and locking with the vessel lid sealing gasket. The closure assembly consists of a thick walled sleeve insert for retention in the under bores fabricated in the cover periphery and the sleeve is provided with internal threading only. A snap serves as a retainer on the underside of the sleeve, locking it into an under bore retention channel. Finally, a standard elongate externally threaded bolt is sized for mating cooperation with the so positioned sleeve, whereby the location of the bolt shaft in the cover bore hole determines its compressive contact on the underlying gasket.

  5. Trends in Tissue Engineering for Blood Vessels

    PubMed Central

    Nemeno-Guanzon, Judee Grace; Lee, Soojung; Berg, Johan Robert; Jo, Yong Hwa; Yeo, Jee Eun; Nam, Bo Mi; Koh, Yong-Gon; Lee, Jeong Ik

    2012-01-01

    Over the years, cardiovascular diseases continue to increase and affect not only human health but also the economic stability worldwide. The advancement in tissue engineering is contributing a lot in dealing with this immediate need of alleviating human health. Blood vessel diseases are considered as major cardiovascular health problems. Although blood vessel transplantation is the most convenient treatment, it has been delimited due to scarcity of donors and the patient's conditions. However, tissue-engineered blood vessels are promising alternatives as mode of treatment for blood vessel defects. The purpose of this paper is to show the importance of the advancement on biofabrication technology for treatment of soft tissue defects particularly for vascular tissues. This will also provide an overview and update on the current status of tissue reconstruction especially from autologous stem cells, scaffolds, and scaffold-free cellular transplantable constructs. The discussion of this paper will be focused on the historical view of cardiovascular tissue engineering and stem cell biology. The representative studies featured in this paper are limited within the last decade in order to trace the trend and evolution of techniques for blood vessel tissue engineering. PMID:23251085

  6. Complete resection of locally advanced ovarian carcinoma fixed to the pelvic sidewall and involving external and internal iliac vessels.

    PubMed

    Nishikimi, Kyoko; Tate, Shinichi; Matsuoka, Ayumu; Shozu, Makio

    2017-08-01

    Locally advanced ovarian carcinomas may be fixed to the pelvic sidewall, and although these often involve the internal iliac vessels, they rarely involve the external iliac vessels. Such tumors are mostly considered inoperable. We present a surgical technique for complete resection of locally advanced ovarian carcinoma fixed to the pelvic sidewall and involving external and internal iliac vessels. A 69-year-old woman presented with ovarian carcinoma fixed to the right pelvic sidewall, which involved the right external and internal iliac arteries and veins and the right lower ureter, rectum, and vagina. We cut the external iliac artery and vein at the bifurcation and at the inguinal ligament to resect the external artery and vein. Then, we reconstructed the arterial and venous supplies of the right external artery and vein with grafts. After creating a wide space immediately inside of the sacral plexus to allow the tumor fixed to pelvic sidewall with the internal iliac vessels to move medially, we performed total internal iliac vessel resection. We achieved complete en bloc tumor resection with the right external and internal artery and vein, right ureter, vagina, and rectum adhering to the tumor. There were no intra- or postoperative complications, such as bleeding, graft occlusion, infection, or limb edema. Exfoliation from the sacral plexus and total resection with external and internal iliac vessels enables complete resection of the tumor fixed to the pelvic sidewall. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Intimal hyperplasia induced by vascular intervention causes lipoprotein retention and accelerated atherosclerosis.

    PubMed

    Kijani, Siavash; Vázquez, Ana Maria; Levin, Malin; Borén, Jan; Fogelstrand, Per

    2017-07-01

    Accelerated atherosclerosis diminishes the long term patency of vascular interventions, such as percutaneous coronary intervention and implantation of saphenous vein grafts. However, the cause of this accelerated atherosclerosis is unclear. In this study, we tested the hypothesis that intimal hyperplasia formed following vascular intervention promotes retention of atherogenic lipoproteins. Intimal hyperplasia was surgically induced in the mouse common carotid artery. The surgery was combined with different mouse models of hypercholesterolemia to obtain different cholesterol levels and to control the onsets of hypercholesterolemia. Three weeks after surgery, samples were immunostained for apoB lipoproteins, smooth muscle cells and leukocytes. Already at mild hypercholesterolemia (193 mg/dL), pronounced apoB lipoprotein retention was found in the extracellular matrix in both intimal hyperplasia and the injured underlying media. In contrast, minimal retention was detected in the uninjured proximal region of the same vessel, or in vessels from mice with normal cholesterol levels (81 mg/dL). Induction of aggravated hypercholesterolemia 3 weeks after surgery, when a mature intimal hyperplasia had been formed, caused a very rapid development of atherosclerotic lesions. Mechanistically, we show that lipoprotein retention was almost exclusively dependent on electrostatic interactions to proteoglycan glycosaminoglycans, and the lipoprotein retention to intimal hyperplasia could be inhibited in vivo using glycosaminoglycan-binding antibodies. Thus, formation of intimal hyperplasia following vascular intervention makes the vessel wall highly susceptible for lipoprotein retention and accelerated atherosclerosis. The increased lipoprotein retention in intimal hyperplasia can be targeted by blocking the interaction between apoB lipoproteins and glycosaminoglycans in the extracellular matrix. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on

  8. 50 CFR 679.27 - Improved Retention/Improved Utilization Program.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... prohibited all fish of that species brought on board the vessel up to the MRA for that species. (C) Retention... on board equals the MRA for that species. (C) Retention of an IR/IU species is prohibited no fish or... the point that the round-weight equivalent of primary products on board equals the MRA for that...

  9. 50 CFR 679.27 - Improved Retention/Improved Utilization Program.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... prohibited all fish of that species brought on board the vessel up to the MRA for that species. (C) Retention... on board equals the MRA for that species. (C) Retention of an IR/IU species is prohibited no fish or... the point that the round-weight equivalent of primary products on board equals the MRA for that...

  10. 50 CFR 679.27 - Improved Retention/Improved Utilization Program.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... IR/IU species is prohibited all fish of that species brought on board the vessel up to the MRA for... equivalent of primary products on board equals the MRA for that species. (C) Retention of an IR/IU species is... MRA for that species. (C) Retention of an IR/IU species is prohibited no fish or product of that...

  11. 50 CFR 679.27 - Improved Retention/Improved Utilization Program.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... IR/IU species is prohibited all fish of that species brought on board the vessel up to the MRA for... equivalent of primary products on board equals the MRA for that species. (C) Retention of an IR/IU species is... MRA for that species. (C) Retention of an IR/IU species is prohibited no fish or product of that...

  12. 50 CFR 679.27 - Improved Retention/Improved Utilization Program.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... IR/IU species is prohibited all fish of that species brought on board the vessel up to the MRA for... equivalent of primary products on board equals the MRA for that species. (C) Retention of an IR/IU species is... MRA for that species. (C) Retention of an IR/IU species is prohibited no fish or product of that...

  13. Simply actuated closure for a pressure vessel - Design for use to trap deep-sea animals

    NASA Technical Reports Server (NTRS)

    Yayanos, A. A.

    1977-01-01

    A pressure vessel is described that can be closed by a single translational motion within 1 sec. The vessel is a key component of a trap for small marine animals and operates automatically on the sea floor. As the vessel descends to the sea floor, it is subjected both internally and externally to the high pressures of the deep sea. The mechanism for closing the pressure vessel on the sea floor is activated by the timed release of the ballast which was used to sink the trap. As it rises to the sea surface, the internal pressure of the vessel remains near the value present on the sea floor. The pressure vessel has been used in simulated ocean deployments and in the deep ocean (9500 m) with a 75%-85% retention of the deep-sea pressure. Nearly 100% retention of pressure can be achieved by using an accumulator filled with a gas.

  14. Retention of mandibular advancement devices in the treatment of obstructive sleep apnea: an in vitro pilot study.

    PubMed

    Vanderveken, Olivier M; Van de Heyning, Paul; Braem, Marc J

    2014-05-01

    In order for a mandibular advancement device (MAD) to be efficacious, it must remain seated on the teeth during sleep. Quantitative data on the retentive characteristics of MADs are currently unavailable. The present pilot study is the first to describe an in vitro setup testing the retentive characteristics of different monobloc MADs. A hydraulic cyclic test machine was used with MADs seated on dental casts to measure retention forces upon removal of the MADs. A custom-made monobloc (CM-mono), a thermoplastic monobloc (TP-mono), and a thermoplastic duobloc (TP-duo) configured as a monobloc were tested. Two protrusions were investigated, representing 25 and 65% of the maximal protrusion. The effects of the type of MAD, duration of the test, and amount of protrusion on removal forces were measured. The measured removal forces of all three MADs tested differed significantly, with the TP-duo showing the highest values (P < 0.0001). The effects of wear due to the repetitive cyclic loading became obvious by the production of wear particles in all MADs tested. However, only the TP-duo showed a significant reduction in time in removal forces for both protrusion positions (P < 0.0001; P = 0.0011). The effect of the amount of protrusion on the removal forces differed significantly between all three MADs tested (P = 0.0074). This in vitro pilot study reveals significant differences in retention forces for the MADs tested. The findings are consistent with clinical effects of nightly loss of MADs as reported in the literature and are within the range of reported physiological mouth-opening forces. Future research is needed to determine the key design features of MADs that explain these differences.

  15. 50 CFR 635.24 - Commercial retention limits for sharks and swordfish.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 12 2012-10-01 2012-10-01 false Commercial retention limits for sharks... Management Measures § 635.24 Commercial retention limits for sharks and swordfish. Link to an amendment.... (a) Sharks. (1) A person who owns or operates a vessel that has been issued a valid shark research...

  16. Thick SS316 materials TIG welding development activities towards advanced fusion reactor vacuum vessel applications

    NASA Astrophysics Data System (ADS)

    Kumar, B. Ramesh; Gangradey, R.

    2012-11-01

    Advanced fusion reactors like ITER and up coming Indian DEMO devices are having challenges in terms of their materials design and fabrication procedures. The operation of these devices is having various loads like structural, thermo-mechanical and neutron irradiation effects on major systems like vacuum vessel, divertor, magnets and blanket modules. The concept of double wall vacuum vessel (VV) is proposed in view of protecting of major reactor subsystems like super conducting magnets, diagnostic systems and other critical components from high energy 14 MeV neutrons generated from fusion plasma produced by D-T reactions. The double walled vacuum vessel is used in combination with pressurized water circulation and some special grade borated steel blocks to shield these high energy neutrons effectively. The fabrication of sub components in VV are mainly used with high thickness SS materials in range of 20 mm- 60 mm of various grades based on the required protocols. The structural components of double wall vacuum vessel uses various parts like shields, ribs, shells and diagnostic vacuum ports. These components are to be developed with various welding techniques like TIG welding, Narrow gap TIG welding, Laser welding, Hybrid TIG laser welding, Electron beam welding based on requirement. In the present paper the samples of 20 mm and 40 mm thick SS 316 materials are developed with TIG welding process and their mechanical properties characterization with Tensile, Bend tests and Impact tests are carried out. In addition Vickers hardness tests and microstructural properties of Base metal, Heat Affected Zone (HAZ) and Weld Zone are done. TIG welding application with high thick SS materials in connection with vacuum vessel requirements and involved criticalities towards welding process are highlighted.

  17. An Investigation of the North Carolina Center for the Advancement of Teaching and Its Possible Influence on Beginning Teacher Retention: A Companion Dissertation

    ERIC Educational Resources Information Center

    Shook, Anna Lorraine Braverman

    2015-01-01

    An Investigation of the North Carolina Center for the Advancement of Teaching and its Influence on Beginning Teacher Retention: A Companion Dissertation. Shook, Anna, 2015. Dissertation, Gardner-Webb University, Adult Learning Theory/Adult Developmental Theory/Professional Development/Beginning Teacher/North Carolina Center for the Advancement of…

  18. Pharmacological and Physical Vessel Modulation Strategies to Improve EPR-mediated Drug Targeting to Tumors

    PubMed Central

    Ojha, Tarun; Pathak, Vertika; Shi, Yang; Hennink, Wim; Moonen, Chrit; Storm, Gert; Kiessling, Fabian; Lammers, Twan

    2018-01-01

    The performance of nanomedicine formulations depends on the Enhanced Permeability and Retention (EPR) effect. Prototypic nanomedicine-based drug delivery systems, such as liposomes, polymers and micelles, aim to exploit the EPR effect to accumulate at pathological sites, to thereby improve the balance between drug efficacy and toxicity. Thus far, however, tumor-targeted nanomedicines have not yet managed to achieve convincing therapeutic results, at least not in large cohorts of patients. This is likely mostly due to high inter- and intra-patient heterogeneity in EPR. Besides developing (imaging) biomarkers to monitor and predict EPR, another strategy to address this heterogeneity is the establishment of vessel modulation strategies to homogenize and improve EPR. Over the years, several pharmacological and physical co-treatments have been evaluated to improve EPR-mediated tumor targeting. These include pharmacological strategies, such as vessel permeabilization, normalization, disruption and promotion, as well as physical EPR enhancement via hyperthermia, radiotherapy, sonoporation and phototherapy. In the present manuscript, we summarize exemplary studies showing that pharmacological and physical vessel modulation strategies can be used to improve tumor-targeted drug delivery, and we discuss how these advanced combination regimens can be optimally employed to enhance the (pre-) clinical performance of tumor-targeted nanomedicines. PMID:28697952

  19. Pharmacological and physical vessel modulation strategies to improve EPR-mediated drug targeting to tumors.

    PubMed

    Ojha, Tarun; Pathak, Vertika; Shi, Yang; Hennink, Wim E; Moonen, Chrit T W; Storm, Gert; Kiessling, Fabian; Lammers, Twan

    2017-09-15

    The performance of nanomedicine formulations depends on the Enhanced Permeability and Retention (EPR) effect. Prototypic nanomedicine-based drug delivery systems, such as liposomes, polymers and micelles, aim to exploit the EPR effect to accumulate at pathological sites, to thereby improve the balance between drug efficacy and toxicity. Thus far, however, tumor-targeted nanomedicines have not yet managed to achieve convincing therapeutic results, at least not in large cohorts of patients. This is likely mostly due to high inter- and intra-patient heterogeneity in EPR. Besides developing (imaging) biomarkers to monitor and predict EPR, another strategy to address this heterogeneity is the establishment of vessel modulation strategies to homogenize and improve EPR. Over the years, several pharmacological and physical co-treatments have been evaluated to improve EPR-mediated tumor targeting. These include pharmacological strategies, such as vessel permeabilization, normalization, disruption and promotion, as well as physical EPR enhancement via hyperthermia, radiotherapy, sonoporation and phototherapy. In the present manuscript, we summarize exemplary studies showing that pharmacological and physical vessel modulation strategies can be used to improve tumor-targeted drug delivery, and we discuss how these advanced combination regimens can be optimally employed to enhance the (pre-) clinical performance of tumor-targeted nanomedicines. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Effect of simulation on knowledge of advanced cardiac life support, knowledge retention, and confidence of nursing students in Jordan.

    PubMed

    Tawalbeh, Loai I; Tubaishat, Ahmad

    2014-01-01

    This study examined the effect of simulation on nursing students' knowledge of advanced cardiac life support (ACLS), knowledge retention, and confidence in applying ACLS skills. An experimental, randomized controlled (pretest-posttest) design was used. The experimental group (n = 40) attended an ACLS simulation scenario, a 4-hour PowerPoint presentation, and demonstration on a static manikin, whereas the control group (n = 42) attended the PowerPoint presentation and a demonstration only. A paired t test indicated that posttest mean knowledge of ACLS and confidence was higher in both groups. The experimental group showed higher knowledge of ACLS and higher confidence in applying ACLS, compared with the control group. Traditional training involving PowerPoint presentation and demonstration on a static manikin is an effective teaching strategy; however, simulation is significantly more effective than traditional training in helping to improve nursing students' knowledge acquisition, knowledge retention, and confidence about ACLS. Copyright 2014, SLACK Incorporated.

  1. Sealing vessels up to 7 mm in diameter solely with ultrasonic technology.

    PubMed

    Timm, Richard W; Asher, Ryan M; Tellio, Karalyn R; Welling, Alissa L; Clymer, Jeffrey W; Amaral, Joseph F

    2014-01-01

    Ultrasonic energy is a mainstay in the armamentarium of surgeons, providing multifunctionality, precision, and control when dissecting and sealing vessels up to 5 mm in diameter. Historically, the inability to seal vessels in the 5-7 mm range has been perceived as an inherent limitation of ultrasonic technology. The purpose of this study was to evaluate sealing of vessels up to 7 mm in diameter with an ultrasonic device that modulates energy delivery during the sealing period. In ex vivo benchtop and in vivo acute and survival preclinical models, a new ultrasonic device, Harmonic ACE(®)+7 Shears (Harmonic 7), was compared with advanced bipolar devices in sealing vessels 1-7 mm in diameter with respect of burst pressure, seal reliability, and seal durability. Lateral thermal damage and transection time were also evaluated. Ex vivo tests of Harmonic 7 demonstrated significantly greater median burst pressures than an advanced bipolar device both for vessels <5 mm in diameter (1,078 mmHg and 836 mmHg, respectively, P=0.046) and for those in the range of 5-7 mm (1,419 mmHg and 591 mmHg, P<0.001). In vivo tests in porcine and caprine models demonstrated similar rates of hemostasis between Harmonic 7 and advanced bipolar devices, with high success rates at initial transection and seal durability of 100% after a 30-day survival period. Sealing 5-7 mm vessels is not a limitation of the type of energy used but of how energy is delivered to tissue. These studies document the ability of ultrasonic energy alone to reliably seal large vessels 5-7 mm in diameter, with significantly greater burst pressure observed in in vitro studies than those observed with an advanced bipolar technology when energy delivery is modulated during the sealing cycle. Furthermore, the seals created in 5-7 mm vessels are shown to be reliable and durable in in vivo preclinical studies.

  2. An Approach to Understanding Cohesive Slurry Settling, Mobilization, and Hydrogen Gas Retention in Pulsed Jet Mixed Vessels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gauglitz, Phillip A.; Wells, Beric E.; Fort, James A.

    2009-05-22

    The Hanford Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and vitrify a large portion of the waste in Hanford’s 177 underground waste storage tanks. Numerous process vessels will hold waste at various stages in the WTP. Some of these vessels have mixing-system requirements to maintain conditions where the accumulation of hydrogen gas stays below acceptable limits, and the mixing within the vessels is sufficient to release hydrogen gas under normal conditions and during off-normal events. Some of the WTP process streams are slurries of solid particles suspended in Newtonian fluids that behave as non-Newtonianmore » slurries, such as Bingham yield-stress fluids. When these slurries are contained in the process vessels, the particles can settle and become progressively more concentrated toward the bottom of the vessels, depending on the effectiveness of the mixing system. One limiting behavior is a settled layer beneath a particle-free liquid layer. The settled layer, or any region with sufficiently high solids concentration, will exhibit non-Newtonian rheology where it is possible for the settled slurry to behave as a soft solid with a yield stress. In this report, these slurries are described as settling cohesive slurries.« less

  3. What Are the Consequences of the Newly Implemented 24+Advanced Learning Loans on Retention of Adult Access to Higher Education Students?

    ERIC Educational Resources Information Center

    Burns, Jane Marie; Slack, Kim

    2015-01-01

    This article discusses the previous literature on student retention in the post-compulsory education sector and the "24+Advanced Learning Loan". Adult students participating in an Access to Higher Education course are at particularly high risk of non-completion. Literature indicates that whilst stakeholders may require factual statistics…

  4. New semi-quantitative 123I-MIBG estimation method compared with scoring system in follow-up of advanced neuroblastoma: utility of total MIBG retention ratio versus scoring method.

    PubMed

    Sano, Yuko; Okuyama, Chio; Iehara, Tomoko; Matsushima, Shigenori; Yamada, Kei; Hosoi, Hajime; Nishimura, Tsunehiko

    2012-07-01

    The purpose of this study is to evaluate a new semi-quantitative estimation method using (123)I-MIBG retention ratio to assess response to chemotherapy for advanced neuroblastoma. Thirteen children with advanced neuroblastoma (International Neuroblastoma Risk Group Staging System: stage M) were examined for a total of 51 studies with (123)I-MIBG scintigraphy (before and during chemotherapy). We proposed a new semi-quantitative method using MIBG retention ratio (count obtained with delayed image/count obtained with early image with decay correction) to estimate MIBG accumulation. We analyzed total (123)I-MIBG retention ratio (TMRR: total body count obtained with delayed image/total body count obtained with early image with decay correction) and compared with a scoring method in terms of correlation with tumor markers. TMRR showed significantly higher correlations with urinary catecholamine metabolites before chemotherapy (VMA: r(2) = 0.45, P < 0.05, HVA: r(2) = 0.627, P < 0.01) than MIBG score (VMA: r(2) = 0.19, P = 0.082, HVA: r(2) = 0.25, P = 0.137). There were relatively good correlations between serial change of TMRR and those of urinary catecholamine metabolites (VMA: r(2) = 0.274, P < 0.001, HVA: r(2) = 0.448, P < 0.0001) compared with serial change of MIBG score and those of tumor markers (VMA: r(2) = 0.01, P = 0.537, HVA: 0.084, P = 0.697) during chemotherapy for advanced neuroblastoma. TMRR could be a useful semi-quantitative method for estimating early response to chemotherapy of advanced neuroblastoma because of its high correlation with urine catecholamine metabolites.

  5. 33 CFR 164.61 - Marine casualty reporting and record retention.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Marine casualty reporting and... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.61 Marine casualty reporting and record retention. When a vessel is involved in a marine casualty as defined in 46...

  6. 33 CFR 164.61 - Marine casualty reporting and record retention.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Marine casualty reporting and... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.61 Marine casualty reporting and record retention. When a vessel is involved in a marine casualty as defined in 46...

  7. 33 CFR 164.61 - Marine casualty reporting and record retention.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Marine casualty reporting and... HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY NAVIGATION SAFETY REGULATIONS § 164.61 Marine casualty reporting and record retention. When a vessel is involved in a marine casualty as defined in 46...

  8. Real-time monitoring of hemodynamic changes in tumor vessels during photoimmunotherapy using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Liang, Chia-Pin; Nakajima, Takahito; Watanabe, Rira; Sato, Kazuhide; Choyke, Peter L.; Chen, Yu; Kobayashi, Hisataka

    2014-09-01

    Photoimmunotherapy (PIT) is a cell-specific cancer therapy based on an armed antibody conjugate that induces rapid and highly selective cancer cell necrosis after exposure to near-infrared (NIR) light. The PIT treatment also induces the superenhanced permeability and retention effect, which allows high concentrations of nanoparticles to accumulate in the tumor bed. In our pilot studies, optical coherence tomography (OCT) reveals dramatic hemodynamic changes during PIT. We developed and applied speckle variance analysis, Doppler flow measurement, bulk motion removal, and automatic region of interest selection to quantify vessel diameter and blood velocity within tumors in vivo. OCT imaging reveals that blood velocity in peripheral tumor vessels quickly drops below the detection limit while the vessel lumen remains open (4 vessels from 3 animals). On the other hand, control tumor vessels (receive NIR illumination but no PIT drug) do not show the sustained blood velocity drop (5 vessels from 3 animals). Ultraslow blood velocity could result in a long drug circulation time in tumor. Increase of the blood pool volume within the central tumor (shown in histology) may be the leading cause of the periphery blood velocity drop and could also increase the drug pool volume in tumor vessels.

  9. Nuclear reactor melt-retention structure to mitigate direct containment heating

    DOEpatents

    Tutu, Narinder K.; Ginsberg, Theodore; Klages, John R.

    1991-01-01

    A light water nuclear reactor melt-retention structure to mitigate the extent of direct containment heating of the reactor containment building. The structure includes a retention chamber for retaining molten core material away from the upper regions of the reactor containment building when a severe accident causes the bottom of the pressure vessel of the reactor to fail and discharge such molten material under high pressure through the reactor cavity into the retention chamber. In combination with the melt-retention chamber there is provided a passageway that includes molten core droplet deflector vanes and has gas vent means in its upper surface, which means are operable to deflect molten core droplets into the retention chamber while allowing high pressure steam and gases to be vented into the upper regions of the containment building. A plurality of platforms are mounted within the passageway and the melt-retention structure to direct the flow of molten core material and help retain it within the melt-retention chamber. In addition, ribs are mounted at spaced positions on the floor of the melt-retention chamber, and grid means are positioned at the entrance side of the retention chamber. The grid means develop gas back pressure that helps separate the molten core droplets from discharged high pressure steam and gases, thereby forcing the steam and gases to vent into the upper regions of the reactor containment building.

  10. The Retention and Attrition of Catholic School Principals

    ERIC Educational Resources Information Center

    Durow, W. Patrick; Brock, Barbara L.

    2004-01-01

    This article reports the results of a study of the retention of principals in Catholic elementary and secondary schools in one Midwestern diocese. Findings revealed that personal needs, career advancement, support from employer, and clearly defined role expectations were key factors in principals' retention decisions. A profile of components of…

  11. Development of heat transfer enhancement techniques for external cooling of an advanced reactor vessel

    NASA Astrophysics Data System (ADS)

    Yang, Jun

    Nucleate boiling is a well-recognized means for passively removing high heat loads (up to ˜106 W/m2) generated by a molten reactor core under severe accident conditions while maintaining relatively low reactor vessel temperature (<800 °C). With the upgrade and development of advanced power reactors, however, enhancing the nucleate boiling rate and its upper limit, Critical Heat Flux (CHF), becomes the key to the success of external passive cooling of reactor vessel undergoing core disrupture accidents. In the present study, two boiling heat transfer enhancement methods have been proposed, experimentally investigated and theoretically modelled. The first method involves the use of a suitable surface coating to enhance downward-facing boiling rate and CHF limit so as to substantially increase the possibility of reactor vessel surviving high thermal load attack. The second method involves the use of an enhanced vessel/insulation design to facilitate the process of steam venting through the annular channel formed between the reactor vessel and the insulation structure, which in turn would further enhance both the boiling rate and CHF limit. Among the various available surface coating techniques, metallic micro-porous layer surface coating has been identified as an appropriate coating material for use in External Reactor Vessel Cooling (ERVC) based on the overall consideration of enhanced performance, durability, the ease of manufacturing and application. Since no previous research work had explored the feasibility of applying such a metallic micro-porous layer surface coating on a large, downward facing and curved surface such as the bottom head of a reactor vessel, a series of characterization tests and experiments were performed in the present study to determine a suitable coating material composition and application method. Using the optimized metallic micro-porous surface coatings, quenching and steady-state boiling experiments were conducted in the Sub

  12. Retention of iron by infants.

    PubMed

    Fomon, S J; Nelson, S E; Ziegler, E E

    2000-01-01

    Throughout the world, the most common nutritional deficiency disorder of infants is iron deficiency. Developing effective strategies for preventing iron deficiency requires detailed knowledge of iron retention under ordinary living conditions. For the adult population, such knowledge is at an advanced stage, but relatively little is known about infants. Many reports of iron retention by infants have been based on the assumption that, as in normal and iron-deficient adults, 80%-100% of newly absorbed iron is promptly incorporated into circulating erythrocytes, but this assumption is not supported by available data. This communication presents a review of iron retention by term and preterm infants, as determined by metabolic balance studies or (59)Fe whole-body counting studies, and it explores the relationship between iron retention and postnatal age, iron nutritional status, iron intake (or dose), and type of feeding.

  13. Retinal imaging analysis based on vessel detection.

    PubMed

    Jamal, Arshad; Hazim Alkawaz, Mohammed; Rehman, Amjad; Saba, Tanzila

    2017-07-01

    With an increase in the advancement of digital imaging and computing power, computationally intelligent technologies are in high demand to be used in ophthalmology cure and treatment. In current research, Retina Image Analysis (RIA) is developed for optometrist at Eye Care Center in Management and Science University. This research aims to analyze the retina through vessel detection. The RIA assists in the analysis of the retinal images and specialists are served with various options like saving, processing and analyzing retinal images through its advanced interface layout. Additionally, RIA assists in the selection process of vessel segment; processing these vessels by calculating its diameter, standard deviation, length, and displaying detected vessel on the retina. The Agile Unified Process is adopted as the methodology in developing this research. To conclude, Retina Image Analysis might help the optometrist to get better understanding in analyzing the patient's retina. Finally, the Retina Image Analysis procedure is developed using MATLAB (R2011b). Promising results are attained that are comparable in the state of art. © 2017 Wiley Periodicals, Inc.

  14. Large boron--epoxy filament-wound pressure vessels

    NASA Technical Reports Server (NTRS)

    Jensen, W. M.; Bailey, R. L.; Knoell, A. C.

    1973-01-01

    Advanced composite material used to fabricate pressure vessel is prepeg (partially cured) consisting of continuous, parallel boron filaments in epoxy resin matrix arranged to form tape. To fabricate chamber, tape is wound on form which must be removable after composite has been cured. Configuration of boron--epoxy composite pressure vessel was determined by computer program.

  15. Advanced Dependent Pressure Vessel (DPV) nickel-hydrogen spacecraft cell and battery design

    NASA Technical Reports Server (NTRS)

    Coates, Dwaine; Wright, Doug; Repplinger, Ron

    1995-01-01

    The dependent pressure vessel (DPV) nickel-hydrogen (NiH2) battery is being developed as a potential spacecraft battery design for both military and commercial satellites. Individual pressure vessel (IPV) NiH2 batteries are currently flying on more than 70 Earth orbital satellites and have accumulated more than 140,000,000 cell-hours in actual spacecraft operation. The limitations of standard NiH2 IPV flight battery technology are primarily related to the internal cell design and the battery packaging issues associated with grouping multiple cylindrical cells. The DPV cell design offers higher specific energy and reduced cost, while retaining the established IPV NiH2 technology flight heritage and database. The advanced cell design offers a more efficient mechanical, electrical and thermal cell configuration and a reduced parts count. The internal electrode stack is a prismatic flat-plate arrangement. The flat individual cell pressure vessel provides a maximum direct thermal path for removing heat from the electrode stack. The cell geometry also minimizes multiple-cell battery packaging constraints by using an established end-plateltie-rod battery design. A major design advantage is that the battery support structure is efficiently required to restrain only the force applied to a portion of the end cell. As the cells are stacked in series to achieve the desired system voltage, this increment of the total battery weight becomes small. The geometry of the DPV cell promotes compact, minimum volume packaging and places all cell terminals along the length of the battery. The resulting ability to minimize intercell wiring offers additional design simplicity and significant weight savings. The DPV battery design offers significant cost and weight savings advantages while providing minimal design risks. Cell and battery level design issues will be addressed including mechanical, electrical and thermal design aspects. A design performance analysis will be presented at both

  16. Assessement of angiogenesis reveals blood vessel heterogeneity in lung carcinoma

    PubMed Central

    BIRAU, AMALIA; CEAUSU, RALUCA AMALIA; CIMPEAN, ANCA MARIA; GAJE, PUSA; RAICA, MARIUS; OLARIU, TEODORA

    2012-01-01

    Despite advances in treatment, the prognosis for lung cancer patients remains poor. Angiogenesis appears to be a promising target for lung cancer therapy; however, the clinical significance of vascular changes are not completely understood. The aim of this study was to evaluate the types and morphology of blood vessels in various lung carcinomas. Using double immunostaining, we investigated 39 biopsies from patients admitted with various histological types of lung carcinoma. Tumor blood vessels were quantified separately for CD34/smooth muscle actin and described as either immature, intermediate or mature. Double immunostaining evaluation of the type of blood vessels in lung carcinomas revealed a marked heterogeneity. The immature and intermediate type of vessels were more common in adenocarcinomas (ADCs) and squamous cell carcinomas (SCCs) of the lung. Small cell lung carcinomas revealed a significant correlation between pathological and immature types of blood vessels. Therefore, quantifying the types of tumor vessels in lung carcinomas may be an important element to improve the results of anti-vascular therapy. PMID:23205116

  17. In-vessel visible inspection system on KSTAR

    NASA Astrophysics Data System (ADS)

    Chung, Jinil; Seo, D. C.

    2008-08-01

    To monitor the global formation of the initial plasma and damage to the internal structures of the vacuum vessel, an in-vessel visible inspection system has been installed and operated on the Korean superconducting tokamak advanced research (KSTAR) device. It consists of four inspection illuminators and two visible/H-alpha TV cameras. Each illuminator uses four 150W metal-halide lamps with separate lamp controllers, and programmable progressive scan charge-coupled device cameras with 1004×1004 resolution at 48frames/s and a resolution of 640×480 at 210frames/s are used to capture images. In order to provide vessel inspection capability under any operation condition, the lamps and cameras are fully controlled from the main control room and protected by shutters from deposits during plasma operation. In this paper, we describe the design and operation results of the visible inspection system with the images of the KSTAR Ohmic discharges during the first plasma campaign.

  18. Vessel wall characterization using quantitative MRI: what's in a number?

    PubMed

    Coolen, Bram F; Calcagno, Claudia; van Ooij, Pim; Fayad, Zahi A; Strijkers, Gustav J; Nederveen, Aart J

    2018-02-01

    The past decade has witnessed the rapid development of new MRI technology for vessel wall imaging. Today, with advances in MRI hardware and pulse sequences, quantitative MRI of the vessel wall represents a real alternative to conventional qualitative imaging, which is hindered by significant intra- and inter-observer variability. Quantitative MRI can measure several important morphological and functional characteristics of the vessel wall. This review provides a detailed introduction to novel quantitative MRI methods for measuring vessel wall dimensions, plaque composition and permeability, endothelial shear stress and wall stiffness. Together, these methods show the versatility of non-invasive quantitative MRI for probing vascular disease at several stages. These quantitative MRI biomarkers can play an important role in the context of both treatment response monitoring and risk prediction. Given the rapid developments in scan acceleration techniques and novel image reconstruction, we foresee the possibility of integrating the acquisition of multiple quantitative vessel wall parameters within a single scan session.

  19. A comparison of two methods for measuring vessel length in woody plants.

    PubMed

    Pan, Ruihua; Geng, Jing; Cai, Jing; Tyree, Melvin T

    2015-12-01

    Vessel lengths are important to plant hydraulic studies, but are not often reported because of the time required to obtain measurements. This paper compares the fast dynamic method (air injection method) with the slower but traditional static method (rubber injection method). Our hypothesis was that the dynamic method should yield a larger mean vessel length than the static method. Vessel length was measured by both methods in current year stems of Acer, Populus, Vitis and Quercus representing short- to long-vessel species. The hypothesis was verified. The reason for the consistently larger values of vessel length is because the dynamic method measures air flow rates in cut open vessels. The Hagen-Poiseuille law predicts that the air flow rate should depend on the product of number of cut open vessels times the fourth power of vessel diameter. An argument is advanced that the dynamic method is more appropriate because it measures the length of the vessels that contribute most to hydraulic flow. If all vessels had the same vessel length distribution regardless of diameter, then both methods should yield the same average length. This supports the hypothesis that large-diameter vessels might be longer than short-diameter vessels in most species. © 2015 John Wiley & Sons Ltd.

  20. Dynamics of VEGF matrix-retention in vascular network patterning

    NASA Astrophysics Data System (ADS)

    Köhn-Luque, A.; de Back, W.; Yamaguchi, Y.; Yoshimura, K.; Herrero, M. A.; Miura, T.

    2013-12-01

    Vascular endothelial growth factor (VEGF) is a central regulator of blood vessel morphogenesis, although its role in patterning of endothelial cells into vascular networks is not fully understood. It has been suggested that binding of soluble VEGF to extracellular matrix components causes spatially restricted cues that guide endothelial cells into network patterns. Yet, current evidence for such a mechanism remains indirect. In this study, we quantitatively analyse the dynamics of VEGF retention in a controlled in vitro situation of human umbilical vascular endothelial cells (HUVECs) in Matrigel. We show that fluorescent VEGF accumulates in pericellular areas and colocalizes with VEGF binding molecules. Analysis of fluorescence recovery after photobleaching reveals that binding/unbinding to matrix molecules dominates VEGF dynamics in the pericellular region. Computational simulations using our experimental measurements of kinetic parameters show that matrix retention of chemotactic signals can lead to the formation of reticular cellular networks on a realistic timescale. Taken together, these results show that VEGF binds to matrix molecules in proximity of HUVECs in Matrigel, and suggest that bound VEGF drives vascular network patterning.

  1. Deuterium retention and surface modification of tungsten macrobrush samples exposed in FTU Tokamak

    NASA Astrophysics Data System (ADS)

    Maddaluno, G.; Giacomi, G.; Rufoloni, A.; Verdini, L.

    2007-06-01

    The effect of discrete structures such as macrobrush or castellated surfaces on power handling and deuterium retention of plasma facing components is to be assessed since such geometrical configurations are needed for increasing the lifetime of the armour to heat-sink joint. Four small macrobrush W and W + 1%La2O3 samples have been exposed in the Frascati Tokamak Upgrade (FTU) scrape-off layer up to the last closed flux surface by means of the Sample Introduction System. FTU is an all metal machine with no carbon source inside vacuum vessel; it exhibits ITER relevant energy and particle fluxes on the plasma facing components. Here, results on morphological surface changes (SEM), chemical composition (EDX) and deuterium retention (TDS) are reported.

  2. Safety and Efficacy of Advanced Bipolar Vessel Sealing in Vaginal Hysterectomy: 1000 Cases.

    PubMed

    Clavé, Henri; Clavé, Arnaud

    2017-02-01

    To determine the safety and efficacy of advanced electrothermal bipolar vessel sealing (EBVS) during vaginal hysterectomy by evaluating urinary complications, overall complications, and reoperation rate. A retrospective cohort (Canadian Task Force classification III). High-volume gynecologic surgeon practice, private hospital. One thousand consecutive patients who have undergone vaginal hysterectomy for benign conditions carried out with EBVS between January 2002 and December 2012. Vaginal hysterectomy performed using an EBVS device. One thousand consecutive patients underwent vaginal hysterectomy with advanced EBVS between January 2002 and December 2012 with an average age of 51.4 ± 8.9 years (range, 31-88) and mean weight and body mass index of 57.4 ± 7.2 kg (range, 42-105) and 25.8 ± 4.2 kg/m 2 (range, 19.1-38.9), respectively. Eighty-five percent of patients (852/1000) were healthy without any severe systemic disease. A single experienced surgeon performed all vaginal hysterectomies with EBVS, specifically by not applying traction during thermofusion to avoid hemorrhage, amputating the cervix to transform the uterus to an apple shape to facilitate a vaginal approach and rotation of the uterus, and placing bi-clamp forceps on the edge of the uterus and not at a 45- or 90-degree angle. Wound closure was completed with a continuous suture. Eleven urinary complications (1.1%) were recorded (10 bladder mechanical injuries and 1 vesicovaginal fistula). This was not statistically different from the rate of .64% previously reported in the FINHYST study (p = .15). The overall rate of complications was 5.3%, and 20 patients (2.0%) required reoperation. The presence of uterine scar tissue (odds ratio, 5.5; 95% confidence interval, 1.6-19.2) and larger uterus size (odds ratio, 2.5; 95% confidence interval, 1.01-19.2) were associated with a higher risk of urinary complications. The use of EBVS during vaginal hysterectomy results in urinary and overall

  3. Registered nurse retention strategies in nursing homes: a two-factor perspective.

    PubMed

    Hunt, Selina R; Probst, Janice C; Haddock, Kathlyn S; Moran, Robert; Baker, Samuel L; Anderson, Ruth A; Corazzini, Kirsten

    2012-01-01

    As the American population ages and the proportion of individuals over the age of 65 expands, the demand for high-quality nursing home care will increase. However, nursing workforce instability threatens care quality and sustainability in this sector. Despite increasing attention to nursing home staff turnover, far less is known about registered nurse (RN) retention. In this study, the relationships between retention strategies, employee benefits, features of the practice environment, and RN retention were explored. Further, the utility of Herzberg's two-factor theory of motivation as a framework for nursing home retention studies was evaluated. This study was a secondary analysis of the nationally representative 2004 National Nursing Home Survey. The final sample of 1,174 participating nursing homes were either certified by Medicare or Medicaid or licensed by state agencies. We used a weighted multinomial logistic regression using an incremental approach to model the relationships. Although most nursing homes offered some combination of retention programs, the majority of strategies did not have a significant association with the level of RN retention reported by facilities. Director of nursing tenure and other extrinsic factors had the strongest association with RN retention in adjusted analyses. To improve RN retention, organizations may benefit greatly from stabilizing nursing home leadership, especially the director of nursing position. Second, managers of facilities with poor retention may consider adding career ladders for advancement, awarding attendance, and improving employee benefits. As a behavioral outcome of motivation and satisfaction, retention was not explained as expected using Herzberg's two-factor theory.

  4. Recovery of resources for advanced life support space applications: effect of retention time on biodegradation of two crop residues in a fed-batch, continuous stirred tank reactor.

    PubMed

    Strayer, R F; Finger, B W; Alazraki, M P; Cook, K; Garland, J L

    2002-09-01

    Bioreactor retention time is a key process variable that will influence costs that are relevant to long distance space travel or long duration space habitation. However. little is known about the effects of this parameter on the microbiological treatment options that are being proposed for Advanced Life Support (ALS) systems. Two bioreactor studies were designed to examine this variable. In the first one, six retention times ranging from 1.3 to 21.3 days--were run in duplicate, 81 working-volume continuous stirred tank reactors (CSTR) that were fed ALS wheat residues. Ash-free dry weight loss, carbon mineralization, soluble TOC reduction, changes in fiber content (cellulose, hemicellulose, and lignin), bacterial numbers, and mineral recoveries were monitored. At short retention times--1.33 days--biodegradation was poor (total: 16-20%, cellulose - 12%, hemicellulose - 28%) but soluble TOC was decreased by 75-80% and recovery of major crop inorganic nutrients was adequate, except for phosphorus. A high proportion of the total bacteria (ca. 83%) was actively respiring. At the longest retention time tested, 21.3 days, biodegradation was good (total: 55-60%, cellulose ca. 70%, hemicellulose - ca. 55%) and soluble TOC was decreased by 80%. Recovery of major nutrients, except phosphorus, remained adequate. A very low proportion of total bacteria was actively respiring (ca. 16%). The second bioreactor study used potato residue to determine if even shorter retention times could be used (range 0.25-2.0 days). Although overall biodegradation deteriorated, the degradation of soluble TOC continued to be ca. 75%. We conclude that if the goal of ALS bioprocessing is maximal degradation of crop residues, including cellulose, then retention times of 10 days or longer will be needed. If the goal is to provide inorganic nutrients with the smallest volume/weight bioreactor possible, then a retention time of 1 day (or less) is sufficient.

  5. Recovery of resources for advanced life support space applications: effect of retention time on biodegradation of two crop residues in a fed-batch, continuous stirred tank reactor

    NASA Technical Reports Server (NTRS)

    Strayer, R. F.; Finger, B. W.; Alazraki, M. P.; Cook, K.; Garland, J. L.

    2002-01-01

    Bioreactor retention time is a key process variable that will influence costs that are relevant to long distance space travel or long duration space habitation. However. little is known about the effects of this parameter on the microbiological treatment options that are being proposed for Advanced Life Support (ALS) systems. Two bioreactor studies were designed to examine this variable. In the first one, six retention times ranging from 1.3 to 21.3 days--were run in duplicate, 81 working-volume continuous stirred tank reactors (CSTR) that were fed ALS wheat residues. Ash-free dry weight loss, carbon mineralization, soluble TOC reduction, changes in fiber content (cellulose, hemicellulose, and lignin), bacterial numbers, and mineral recoveries were monitored. At short retention times--1.33 days--biodegradation was poor (total: 16-20%, cellulose - 12%, hemicellulose - 28%) but soluble TOC was decreased by 75-80% and recovery of major crop inorganic nutrients was adequate, except for phosphorus. A high proportion of the total bacteria (ca. 83%) was actively respiring. At the longest retention time tested, 21.3 days, biodegradation was good (total: 55-60%, cellulose ca. 70%, hemicellulose - ca. 55%) and soluble TOC was decreased by 80%. Recovery of major nutrients, except phosphorus, remained adequate. A very low proportion of total bacteria was actively respiring (ca. 16%). The second bioreactor study used potato residue to determine if even shorter retention times could be used (range 0.25-2.0 days). Although overall biodegradation deteriorated, the degradation of soluble TOC continued to be ca. 75%. We conclude that if the goal of ALS bioprocessing is maximal degradation of crop residues, including cellulose, then retention times of 10 days or longer will be needed. If the goal is to provide inorganic nutrients with the smallest volume/weight bioreactor possible, then a retention time of 1 day (or less) is sufficient.

  6. In-vessel coolability and retention of a core melt

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Theofanous, T.G.; Liu, C.; Additon, S.

    1997-02-01

    The efficacy of external flooding of a reactor vessel as a severe accident management strategy is assessed for an AP600-like reactor design. The overall approach is based on the Risk Oriented Accident Analysis Methodology (ROAAM), and the assessment includes consideration of bounding scenarios and sensitivity studies, as well as arbitrary parametric evaluations that allow the delineation of the failure boundaries. The technical treatment in this assessment includes: (a) new data on energy flow from either volumetrically heated pools or non-heated layers on top, boiling and critical heat flux in inverted, curved geometries, emissivity of molten (superheated) samples of steel, andmore » chemical reactivity proof tests, (b) a simple but accurate mathematical formulation that allows prediction of thermal loads by means of convenient hand calculations, (c) a detailed model programmed on the computer to sample input parameters over the uncertainty ranges, and to produce probability distributions of thermal loads and margins for departure from nucleate boiling at each angular position on the lower head, and (d) detailed structural evaluations that demonstrate that departure from nucleate boiling is a necessary and sufficient criterion for failure. Quantification of the input parameters is carried out for an AP600-like design, and the results of the assessment demonstrate that lower head failure is {open_quotes}physically unreasonable.{close_quotes} Use of this conclusion for any specific application is subject to verifying the required reliability of the depressurization and cavity-flooding systems, and to showing the appropriateness (in relation to the database presented here, or by further testing as necessary) of the thermal insulation design and of the external surface properties of the lower head, including any applicable coatings.« less

  7. 5 CFR 293.404 - Retention schedule.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... acceptable performance from the date of the written advance notice of the proposed removal or reduction in....404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PERSONNEL RECORDS Employee Performance File System Records § 293.404 Retention schedule. (a)(1) Except as provided...

  8. Advanced Design Features of APR1400 and Realization in Shin Kori Construction Project

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    OH, S.J.; Park, K.C.; Kim, H.G.

    2006-07-01

    APR1400 adopted several advanced design features. To ensure their proper operation as a part of ShinKori 3,4 project, both experimental and analytical work are continuing. In this paper, work on the advanced design features related to enhanced safety is examined. APR1400 safety injection system consists of four independent trains which include four safety injection pump and tanks. A passive flow regulating device called fluidic device is installed in the safety injection tanks. Separate effect tests including a full scale fluidic device tests have been conducted. Integral system tests are in progress. Combination of these work with the analytical work usingmore » RELAP5/Mod3 would ensure the proper operation of the new safety injection systems. To mitigate severe accidents, hydrogen mitigation system using PARs and igniters is adopted. Also, active injection system and the streamlined insulation design are adopted to enhance the in-vessel retention capability with the external cooling of RPV strategy. Analytic work with supporting experiments is performed. We are certain that these preparatory work would help the successful adaptation of ADF in ShinKori project. (authors)« less

  9. New Developments in Nickel-Hydrogen Dependent Pressure Vessel (DPV) Cell and Battery Design

    NASA Technical Reports Server (NTRS)

    Caldwell, Dwight B.; Fox, Chris L.; Miller, Lee E.

    1997-01-01

    THe Dependent Pressure Vessel (DPV) Nickel-Hydrogen (NiH2) design is being developed as an advanced battery for military and commercial, aerospace and terrestrial applications. The DPV cell design offers high specific energy and energy density as well as reduced cost, while retaining the established Individual Pressure Vessel (IPV) technology flight heritage and database. This advanced DPV design also offers a more efficient mechanical, electrical and thermal cell and battery configuration and a reduced part count. The DPV battery design promotes compact, minimum volume packaging and weight efficiency, and delivers cost and weight savings with minimal design risk.

  10. 78 FR 53397 - Atlantic Highly Migratory Species; Vessel Monitoring Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-29

    ... operators by eliminating the requirement to hail-out two hours in advance of leaving port. Additionally... long as the VMS unit was turned on at least two hours prior to leaving port and remained on until the vessel returned to port. These requirements were specific to vessels both holding an HMS permit and...

  11. 76 FR 65155 - Fisheries Off West Coast States; Highly Migratory Species Fisheries; Swordfish Retention Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-20

    ... retention limits for swordfish, Xiphias gladius, harvested in the U.S. West Coast-based deep-set tuna..., there would be no limit on swordfish retained. Regulations prohibiting the use of shallow[hyphen]set..., those regulations prohibit vessels based on the West Coast from using longline gear to make shallow sets...

  12. Large-Vessel Sealing in Laparoscopic Colectomy with an Ultrasonic Device

    PubMed Central

    Plasencia, Gustavo; Van der Speeten, Kurt; Hinoul, Piet; Batiller, Jonathan; Severin, Kimberley S.; Schwiers, Michael L.; Rockall, Tim

    2016-01-01

    Background and Objective: The Harmonic ACE+7 Shears with Advanced Hemostasis Mode (Ethicon, Somerville, NJ, USA) is an ultrasonic device designed to transect and seal vessels up to 7 mm in diameter. The device applies an algorithm that optimizes ultrasonic energy delivery combined with a longer sealing cycle. The purpose of this study was to assess the initial clinical experience with the Harmonic device by evaluating large-vessel sealing during laparoscopic colectomy in consecutive cases. Methods: This prospective, multicenter, observational series involved 40 adult patients who were to undergo elective laparoscopic colectomy where dissection and transection of the inferior mesenteric artery was indicated. The primary study endpoint was first-pass hemostasis, defined as a single activation of the Advanced Hemostasis Mode to transect and seal the inferior mesenteric artery. The use of any additional energy device or hemostatic product to establish or maintain hemostasis was noted. Patients were observed after surgery for ∼4 weeks for adverse events that were considered to be related to the study procedure or study device. Descriptive statistical analyses were performed for study endpoints. Results: Forty patients underwent the laparoscopic colectomy procedure. First-pass hemostasis of the inferior mesenteric artery was achieved and maintained in all 40 patients, with no required additional hemostatic measures. Exposure of the vessel was reported as skeletonized in 22 of 40 (55%) patients. Mean transection time was 21.9 ± 7.4 s. One adverse event (postoperative anemia) was considered possibly related to the study device. Conclusion: In this initial clinical consecutive series, the device demonstrated successful transection and sealing of the large mesenteric vessels during laparoscopic colorectal surgery. PMID:27186065

  13. Evaluation of Progressive Failure Analysis and Modeling of Impact Damage in Composite Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Sanchez, Christopher M.

    2011-01-01

    NASA White Sands Test Facility (WSTF) is leading an evaluation effort in advanced destructive and nondestructive testing of composite pressure vessels and structures. WSTF is using progressive finite element analysis methods for test design and for confirmation of composite pressure vessel performance. Using composite finite element analysis models and failure theories tested in the World-Wide Failure Exercise, WSTF is able to estimate the static strength of composite pressure vessels. Additionally, test and evaluation on composites that have been impact damaged is in progress so that models can be developed to estimate damage tolerance and the degradation in static strength.

  14. Gender Differences in Academic Medicine: Retention, Rank, and Leadership Comparisons From the National Faculty Survey.

    PubMed

    Carr, Phyllis L; Raj, Anita; Kaplan, Samantha E; Terrin, Norma; Breeze, Janis L; Freund, Karen M

    2018-01-30

    Prior studies have found that women in academic medicine do not advance or remain in their careers in parity with men. The authors examined a national cohort of faculty from the 1995 National Faculty Survey to identify predictors of advancement, retention, and leadership for women faculty. The authors followed 1,273 faculty at 24 medical schools in the continental United States for 17 years to identify predictors of advancement, retention, and leadership for women faculty. Schools were balanced for public or private status and the four Association of American Medical Colleges geographic regions. The authors used regression models to adjust for covariates: seniority, department, academic setting, and race/ethnicity. After adjusting for significant covariates women were less likely than men to achieve the rank of professor (OR = 0.57; 95% CI, 0.43-0.78) or to remain in academic careers (OR = 0.68; 95% CI, 0.49-0.94). When number of refereed publications were added to the model, differences by gender in retention and attainment of senior rank were no longer significant. Male faculty were more likely to hold senior leadership positions after adjusting for publications (OR = 0.49; 95% CI, 0.35-0.69). Gender disparities in rank, retention, and leadership remain across the career trajectories of the faculty cohort in this study. Women were less likely to attain senior-level positions than men, even after adjusting for publication-related productivity. Institutions must examine the climate for women to ensure their academic capital is fully utilized and equal opportunity exists for leadership.

  15. Designing of a Fleet-Leader Program for Carbon Composite Overwrapped Pressure Vessels

    NASA Technical Reports Server (NTRS)

    Murthy, Pappu L.N.; Phoenix, S. Leigh

    2009-01-01

    Composite Overwrapped Pressure Vessels (COPVs) are often used for storing pressurant gases on board spacecraft when mass saving is a prime requirement. Substantial weight savings can be achieved compared to all metallic pressure vessels. For example, on the space shuttle, replacement of all metallic pressure vessels with Kevlar COPVs resulted in a weight savings of about 30 percent. Mass critical space applications such as the Ares and Orion vehicles are currently being planned to use as many COPVs as possible in place of all-metallic pressure vessels to minimize the overall mass of the vehicle. Due to the fact that overwraps are subjected to sustained loads during long periods of a mission, stress rupture failure is a major concern. It is, therefore, important to ascertain the reliability of these vessels by analysis, since it is practically impossible to show by experimental testing the reliability of flight quality vessels. Also, it is a common practice to set aside flight quality vessels as "fleet leaders" in a test program where these vessels are subjected to slightly accelerated operating conditions so that they lead the actual flight vessels both in time and load. The intention of fleet leaders is to provide advanced warning if there is a serious design flaw in the vessels so that a major disaster in the flight vessels can be averted with advance warning. On the other hand, the accelerating conditions must be not so severe as to be prone to false alarms. The primary focus of the present paper is to provide an analytical basis for designing a viable fleet leader program for carbon COPVs. The analysis is based on a stress rupture behavior model incorporating Weibull statistics and power-law sensitivity of life to fiber stress level.

  16. Femoral vessel injuries in modern warfare since Vietnam.

    PubMed

    Pearl, Jonathan P; McNally, Michael P; Perdue, Philip W

    2003-09-01

    The incidence of lower extremity injuries is high in modern warfare; however the mortality rate from these injuries is low. Despite the overall low mortality of lower extremity injuries, many deaths in modern conflicts are due to femoral vessel injury. The modern warfare literature was reviewed. In Somalia, 1 of the 14 reported deaths was due to a laceration of the superficial femoral artery. In the Persian Gulf, three deaths were reported in an Army field hospital, one resulted from uncontrolled hemorrhage from a profunda femoris artery wound and two others resulted from traumatic amputations with consequent major arterial injury. Despite the advances in modern body armor, the groin is left unprotected. A strategy to help minimize U.S. casualties in modern warfare may be a method of field hemostasis specifically designed for femoral vessel injury.

  17. Tumor angiogenesis in advanced stage ovarian carcinoma.

    PubMed

    Hollingsworth, H C; Kohn, E C; Steinberg, S M; Rothenberg, M L; Merino, M J

    1995-07-01

    Tumor angiogenesis has been found to have prognostic significance in many tumor types for predicting an increased risk of metastasis. We assessed tumor vascularity in 43 cases of advanced stage (International Federation of Gynecologists and Obstetricians stages III and IV) ovarian cancer by using the highly specific endothelial cell marker CD34. Microvessel counts and stage were associated with disease-free survival and with overall survival by Kaplan-Meier analysis. The plots show that higher stage, higher average vessel count at 200x (200x avg) and 400x (400x avg) magnification and highest vessel count at 400x (400x high) magnification confer a worse prognosis for disease-free survival. Average vessel count of less than 16 (400x avg, P2 = 0.01) and less than 45 (200x avg, P2 = 0.026) suggested a better survival. Similarly, a high vessel count of less than 20 (400x high, P2 = 0.019) conferred a better survival as well. The plots suggest that higher stage, higher average vessel count at 200x and 400x, and highest vessel count at 200x and 400x show a trend to worse overall survival as well. With the Cox proportional hazards model, stage was the best predictor of overall survival, however, the average microvessel count at 400x was found to be the best predictor of disease-free survival. These results suggest that analysis of neovascularization in advanced stage ovarian cancer may be a useful prognostic factor.

  18. 77 FR 15973 - Fisheries Off West Coast States; Highly Migratory Species Fisheries; Swordfish Retention Limits

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-19

    ... Magnuson-Stevens Fishery Conservation and Management Act (MSA) to modify retention limits for swordfish... (RFA). Based on the average observed annual catches by this vessel and the market values for that catch... due to this comment. The second critical comment, submitted on behalf of the Turtle Island Restoration...

  19. Vessel calibre—a potential MRI biomarker of tumour response in clinical trials

    PubMed Central

    Emblem, Kyrre E.; Farrar, Christian T.; Gerstner, Elizabeth R.; Batchelor, Tracy T.; Borra, Ronald J. H.; Rosen, Bruce R.; Sorensen, A. Gregory; Jain, Rakesh K.

    2015-01-01

    Our understanding of the importance of blood vessels and angiogenesis in cancer has increased considerably over the past decades, and the assessment of tumour vessel calibre and structure has become increasingly important for in vivo monitoring of therapeutic response. The preferred method for in vivo imaging of most solid cancers is MRI, and the concept of vessel-calibre MRI has evolved since its initial inception in the early 1990s. Almost a quarter of a century later, unlike traditional contrast-enhanced MRI techniques, vessel-calibre MRI remains widely inaccessible to the general clinical community. The narrow availability of the technique is, in part, attributable to limited awareness and a lack of imaging standardization. Thus, the role of vessel-calibre MRI in early phase clinical trials remains to be determined. By contrast, regulatory approvals of antiangiogenic agents that are not directly cytotoxic have created an urgent need for clinical trials incorporating advanced imaging analyses, going beyond traditional assessments of tumour volume. To this end, we review the field of vessel-calibre MRI and summarize the emerging evidence supporting the use of this technique to monitor response to anticancer therapy. We also discuss the potential use of this biomarker assessment in clinical imaging trials and highlight relevant avenues for future research. PMID:25113840

  20. Survival Analysis of Faculty Retention and Promotion in the Social Sciences by Gender.

    PubMed

    Box-Steffensmeier, Janet M; Cunha, Raphael C; Varbanov, Roumen A; Hoh, Yee Shwen; Knisley, Margaret L; Holmes, Mary Alice

    2015-01-01

    Recruitment and retention of talent is central to the research performance of universities. Existing research shows that, while men are more likely than women to be promoted at the different stages of the academic career, no such difference is found when it comes to faculty retention rates. Current research on faculty retention, however, focuses on careers in science, technology, engineering, and mathematics (STEM). We extend this line of inquiry to the social sciences. We follow 2,218 tenure-track assistant professors hired since 1990 in seven social science disciplines at nineteen U.S. universities from time of hire to time of departure. We also track their time to promotion to associate and full professor. Using survival analysis, we examine gender differences in time to departure and time to promotion. Our methods account for censoring and unobserved heterogeneity, as well as effect heterogeneity across disciplines and cohorts. We find no statistically significant differences between genders in faculty retention. However, we do find that men are more likely to be granted tenure than women. When it comes to promotion to full professor, the results are less conclusive, as the effect of gender is sensitive to model specification. The results corroborate previous findings about gender patterns in faculty retention and promotion. They suggest that advances have been made when it comes to gender equality in retention and promotion, but important differences still persist.

  1. 2D Fast Vessel Visualization Using a Vessel Wall Mask Guiding Fine Vessel Detection

    PubMed Central

    Raptis, Sotirios; Koutsouris, Dimitris

    2010-01-01

    The paper addresses the fine retinal-vessel's detection issue that is faced in diagnostic applications and aims at assisting in better recognizing fine vessel anomalies in 2D. Our innovation relies in separating key visual features vessels exhibit in order to make the diagnosis of eventual retinopathologies easier to detect. This allows focusing on vessel segments which present fine changes detectable at different sampling scales. We advocate that these changes can be addressed as subsequent stages of the same vessel detection procedure. We first carry out an initial estimate of the basic vessel-wall's network, define the main wall-body, and then try to approach the ridges and branches of the vasculature's using fine detection. Fine vessel screening looks into local structural inconsistencies in vessels properties, into noise, or into not expected intensity variations observed inside pre-known vessel-body areas. The vessels are first modelled sufficiently but not precisely by their walls with a tubular model-structure that is the result of an initial segmentation. This provides a chart of likely Vessel Wall Pixels (VWPs) yielding a form of a likelihood vessel map mainly based on gradient filter's intensity and spatial arrangement parameters (e.g., linear consistency). Specific vessel parameters (centerline, width, location, fall-away rate, main orientation) are post-computed by convolving the image with a set of pre-tuned spatial filters called Matched Filters (MFs). These are easily computed as Gaussian-like 2D forms that use a limited range sub-optimal parameters adjusted to the dominant vessel characteristics obtained by Spatial Grey Level Difference statistics limiting the range of search into vessel widths of 16, 32, and 64 pixels. Sparse pixels are effectively eliminated by applying a limited range Hough Transform (HT) or region growing. Major benefits are limiting the range of parameters, reducing the search-space for post-convolution to only masked regions

  2. Automated method for identification and artery-venous classification of vessel trees in retinal vessel networks.

    PubMed

    Joshi, Vinayak S; Reinhardt, Joseph M; Garvin, Mona K; Abramoff, Michael D

    2014-01-01

    The separation of the retinal vessel network into distinct arterial and venous vessel trees is of high interest. We propose an automated method for identification and separation of retinal vessel trees in a retinal color image by converting a vessel segmentation image into a vessel segment map and identifying the individual vessel trees by graph search. Orientation, width, and intensity of each vessel segment are utilized to find the optimal graph of vessel segments. The separated vessel trees are labeled as primary vessel or branches. We utilize the separated vessel trees for arterial-venous (AV) classification, based on the color properties of the vessels in each tree graph. We applied our approach to a dataset of 50 fundus images from 50 subjects. The proposed method resulted in an accuracy of 91.44% correctly classified vessel pixels as either artery or vein. The accuracy of correctly classified major vessel segments was 96.42%.

  3. Retention through redemption.

    PubMed

    Abrashoff, D M

    2001-02-01

    Corporate America and the U.S. Navy share one big problem: employee retention. Today's knowledge workers hop from start-up to start-up. And 40% of the navy's new recruits leave the service before their four-year tours of duty are up. D. Michael Abrashoff came face to face with the navy's retention problem when he took command of the USS Benfold. Before he became captain, sailors couldn't get away from the ship fast enough. Today the vessel is the pride of the Pacific fleet, and sailors from other ships are clamoring to join its crew. In this firsthand account, Abrashoff explains how he got the ship and its crew back on course by breaking bad habits--personal and professional ones--and jettisoning old attitudes. During his 21 months aboard the Benfold, Abrashoff came to realize that in today's technology-intensive U.S. Navy, the traditional command-and-control style wouldn't work. And it hadn't--the Benfold's 310 sailors had cheered derisively when Abrashoff's predecessor had left the ship. So he defied 225 years of navy tradition in his quest to engage the sailors in their work, increase their performance, and keep them around for their entire tours of duty. He retained his crew by redeeming them--showing them how to be not just better sailors but better people, too. That meant breaking them down when they were at their worst and then building them up to reach their best. It also meant personal redemption for Abrashoff; he resolved to really listen to what his sailors were saying. The result? Cost-saving ideas for the entire navy and surging confidence and commitment among crew members.

  4. Employee retention: a customer service approach.

    PubMed

    Gerson, Richard F

    2002-01-01

    Employee retention is a huge problem. There are staff shortages in radiology because not enough people are entering the profession; too many people are leaving the profession for retirement, higher-paying jobs or jobs with less stress; and there are not enough opportunities for career advancement. Staff shortages are exacerbated by difficulty in retaining people who enter the profession. While much work has been focused on recruitment and getting more people "in the front door," I suggest that the bulk of future efforts be focused on employee retention and "closing the back door." Employee retention must be an ongoing process, not a program. Approaches to employee retention that focus on external things, i.e., things that the company can do to or for the employee, generally are not successful. The truth is that employee retention processes must focus on what the employee gets out of the job. The process must be a benefits-based approach that helps employees answer the question, "What's in it for me?" The retention processes must be ongoing and integrated into the daily culture of the company. The best way to keep your employees is to treat them like customers. Customer service works for external customers. We treat them nicely. We work to satisfy them. We help them achieve their goals. Why not do the same for our employees? If positive customer service policies and practices can satisfy and keep external customers, why not adapt these policies and practices for employees? And, there is a service/satisfaction link between employee retention and higher levels of customer satisfaction. Customers prefer dealing with the same employees over and over again. Employee turnover destroys a customer's confidence in the company. Just like a customer does not want to have to "train and educate" a new provider, they do not want to do the same for your "revolving door" employees. So, the key is to keep employees so they in turn will help you keep your customers. Because the

  5. Perforating and deep lymphatic vessels in the knee region: an anatomical study and clinical implications.

    PubMed

    Pan, Wei-Ren; Zeng, Fan-Qiang; Wang, De-Guang; Qiu, Zhi-Qiang

    2017-05-01

    To determine the relationship between the perforating and deep lymphatic vessels in the knee region for clinical implications. Four lower limbs from two unembalmed human cadavers were used. Under a surgical microscope, 6% hydrogen peroxide was employed to detect lymph vessels accompanying the small saphenous vein, anterior tibial, posterior tibial and fibular blood vessels all commencing from distal ends of specimens. Each lymphatic vessel was inserted by a 30-gauge needle and injected with a barium sulphate mixture. Each specimen was dissected, radiographed and photographed to determine the perforating and deep lymphatic vessels in the region. A perforating lymph vessel was observed in the popliteal fossa of each specimen. It arose from the superficial popliteal lymph node and terminated in the deep popliteal lymph node. The anterior tibial, posterior tibial and peroneal lymph vessels were discovered in the region travelling with the corresponding vascular bundles. After penetrating the vascular aperture of the interosseous membrane between the tibia and fibula, the anterior tibial lymph vessel entered directly into the deep popliteal lymph node or converged to either the posterior tibial or fibular lymph vessel, before entering the node. The posterior tibial and peroneal lymph vessels entered the deep popliteal lymph node. The efferent lymph vessel of the deep popliteal lymph node travelled with the femoral vascular bundle. The perforating and deep lymphatic vessels in the knee region has been presented and discussed. The information advances our anatomical knowledge and the results will benefit clinical management. © 2017 Royal Australasian College of Surgeons.

  6. Arctic research vessel design would expand science prospects

    NASA Astrophysics Data System (ADS)

    Elsner, Robert; Kristensen, Dirk

    The U.S. polar marine science community has long declared the need for an arctic research vessel dedicated to advancing the study of northern ice-dominated seas. Planning for such a vessel began 2 decades ago, but competition for funding has prevented construction. A new design program is underway, and it shows promise of opening up exciting possibilities for new research initiatives in arctic marine science.With its latest design, the Arctic Research Vessel (ARV) has grown to a size and capability that will make it the first U.S. academic research vessel able to provide access to the Arctic Ocean. This ship would open a vast arena for new studies in the least known of the world's seas. These studies promise to rank high in national priority because of the importance of the Arctic Ocean as a source of data relating to global climate change. Other issues that demand attention in the Arctic include its contributions to the world's heat budget, the climate history buried in its sediments, pollution monitoring, and the influence of arctic conditions on marine renewable resources.

  7. Let's Talk Learning Analytics: A Framework for Implementation in Relation to Student Retention

    ERIC Educational Resources Information Center

    West, Deborah; Heath, David; Huijser, Henk

    2016-01-01

    This paper presents a dialogical tool for the advancement of learning analytics implementation for student retention in Higher Education institutions. The framework was developed as an outcome of a project commissioned and funded by the Australian Government's "Office for Learning and Teaching". The project took a mixed-method approach…

  8. Scalariform-to-simple transition in vessel perforation plates triggered by differences in climate during the evolution of Adoxaceae

    PubMed Central

    Lens, Frederic; Vos, Rutger A.; Charrier, Guillaume; van der Niet, Timo; Merckx, Vincent; Baas, Pieter; Aguirre Gutierrez, Jesus; Jacobs, Bart; Chacon Dória, Larissa; Smets, Erik; Delzon, Sylvain; Janssens, Steven B.

    2016-01-01

    Background and Aims Angiosperms with simple vessel perforations have evolved many times independently of species having scalariform perforations, but detailed studies to understand why these transitions in wood evolution have happened are lacking. We focus on the striking difference in wood anatomy between two closely related genera of Adoxaceae, Viburnum and Sambucus, and link the anatomical divergence with climatic and physiological insights. Methods After performing wood anatomical observations, we used a molecular phylogenetic framework to estimate divergence times for 127 Adoxaceae species. The conditions under which the genera diversified were estimated using ancestral area reconstruction and optimization of ancestral climates, and xylem-specific conductivity measurements were performed. Key Results Viburnum, characterized by scalariform vessel perforations (ancestral), diversified earlier than Sambucus, having simple perforations (derived). Ancestral climate reconstruction analyses point to cold temperate preference for Viburnum and warm temperate for Sambucus. This is reflected in the xylem-specific conductivity rates of the co-occurring species investigated, showing that Viburnum lantana has rates much lower than Sambucus nigra. Conclusions The lack of selective pressure for high conductive efficiency during early diversification of Viburnum and the potentially adaptive value of scalariform perforations in frost-prone cold temperate climates have led to retention of the ancestral vessel perforation type, while higher temperatures during early diversification of Sambucus have triggered the evolution of simple vessel perforations, allowing more efficient long-distance water transport. PMID:27498812

  9. Survival Analysis of Faculty Retention and Promotion in the Social Sciences by Gender

    PubMed Central

    Varbanov, Roumen A.; Hoh, Yee Shwen; Knisley, Margaret L.; Holmes, Mary Alice

    2015-01-01

    Background Recruitment and retention of talent is central to the research performance of universities. Existing research shows that, while men are more likely than women to be promoted at the different stages of the academic career, no such difference is found when it comes to faculty retention rates. Current research on faculty retention, however, focuses on careers in science, technology, engineering, and mathematics (STEM). We extend this line of inquiry to the social sciences. Methods We follow 2,218 tenure-track assistant professors hired since 1990 in seven social science disciplines at nineteen U.S. universities from time of hire to time of departure. We also track their time to promotion to associate and full professor. Using survival analysis, we examine gender differences in time to departure and time to promotion. Our methods account for censoring and unobserved heterogeneity, as well as effect heterogeneity across disciplines and cohorts. Results We find no statistically significant differences between genders in faculty retention. However, we do find that men are more likely to be granted tenure than women. When it comes to promotion to full professor, the results are less conclusive, as the effect of gender is sensitive to model specification. Conclusions The results corroborate previous findings about gender patterns in faculty retention and promotion. They suggest that advances have been made when it comes to gender equality in retention and promotion, but important differences still persist. PMID:26580565

  10. Using Vessel Monitoring System Data to Identify and Characterize Trips Made by Fishing Vessels in the United States North Pacific

    PubMed Central

    Haynie, Alan C.

    2016-01-01

    Time spent fishing is the effort metric often studied in fisheries but it may under-represent the effort actually expended by fishers. Entire fishing trips, from the time vessels leave port until they return, may prove more useful for examining trends in fleet dynamics, fisher behavior, and fishing costs. However, such trip information is often difficult to resolve. We identified ~30,000 trips made by vessels that targeted walleye pollock (Gadus chalcogrammus) in the Eastern Bering Sea from 2008–2014 by using vessel monitoring system (VMS) and landings data. We compared estimated trip durations to observer data, which were available for approximately half of trips. Total days at sea were estimated with < 1.5% error and 96.4% of trip durations were either estimated with < 5% error or they were within expected measurement error. With 99% accuracy, we classified trips as fishing for pollock, for another target species, or not fishing. This accuracy lends strong support to the use of our method with unobserved trips across North Pacific fisheries. With individual trips resolved, we examined potential errors in datasets which are often viewed as “the truth.” Despite having > 5 million VMS records (timestamps and vessel locations), this study was as much about understanding and managing data errors as it was about characterizing trips. Missing VMS records were pervasive and they strongly influenced our approach. To understand implications of missing data on inference, we simulated removal of VMS records from trips. Removal of records straightened (i.e., shortened) vessel trajectories, and travel distances were underestimated, on average, by 1.5–13.4% per trip. Despite this bias, VMS proved robust for trip characterization and for improved quality control of human-recorded data. Our scrutiny of human-reported and VMS data advanced our understanding of the potential utility and challenges facing VMS users globally. PMID:27788174

  11. Using Vessel Monitoring System Data to Identify and Characterize Trips Made by Fishing Vessels in the United States North Pacific.

    PubMed

    Watson, Jordan T; Haynie, Alan C

    2016-01-01

    Time spent fishing is the effort metric often studied in fisheries but it may under-represent the effort actually expended by fishers. Entire fishing trips, from the time vessels leave port until they return, may prove more useful for examining trends in fleet dynamics, fisher behavior, and fishing costs. However, such trip information is often difficult to resolve. We identified ~30,000 trips made by vessels that targeted walleye pollock (Gadus chalcogrammus) in the Eastern Bering Sea from 2008-2014 by using vessel monitoring system (VMS) and landings data. We compared estimated trip durations to observer data, which were available for approximately half of trips. Total days at sea were estimated with < 1.5% error and 96.4% of trip durations were either estimated with < 5% error or they were within expected measurement error. With 99% accuracy, we classified trips as fishing for pollock, for another target species, or not fishing. This accuracy lends strong support to the use of our method with unobserved trips across North Pacific fisheries. With individual trips resolved, we examined potential errors in datasets which are often viewed as "the truth." Despite having > 5 million VMS records (timestamps and vessel locations), this study was as much about understanding and managing data errors as it was about characterizing trips. Missing VMS records were pervasive and they strongly influenced our approach. To understand implications of missing data on inference, we simulated removal of VMS records from trips. Removal of records straightened (i.e., shortened) vessel trajectories, and travel distances were underestimated, on average, by 1.5-13.4% per trip. Despite this bias, VMS proved robust for trip characterization and for improved quality control of human-recorded data. Our scrutiny of human-reported and VMS data advanced our understanding of the potential utility and challenges facing VMS users globally.

  12. Tailoring vessel morphology in vivo

    NASA Astrophysics Data System (ADS)

    Gould, Daniel Joseph

    Tissue engineering is a rapidly growing field which seeks to provide alternatives to organ transplantation in order to address the increasing need for transplantable tissues. One huge hurdle in this effort is the provision of thick tissues; this hurdle exists because currently there is no way to provide prevascularized or rapidly vascularizable scaffolds. To design thick, vascularized tissues, scaffolds are needed that can induce vessels which are similar to the microvasculature found in normal tissues. Angiogenic biomaterials are being developed to provide useful scaffolds to address this problem. In this thesis angiogenic and cell signaling and adhesion factors were incorporated into a biomimetic poly(ethylene glycol) (PEG) hydrogel system. The composition of these hydrogels was precisely tuned to induce the formation of differing vessel morphology. To sensitively measure induced microvascular morphology and to compare it to native microvessels in several tissues, this thesis developed an image-based tool for quantification of scale invariant and classical measures of vessel morphology. The tool displayed great utility in the comparison of native vessels and remodeling vessels in normal tissues. To utilize this tool to tune the vessel response in vivo, Flk1::myr-mCherry fluorescently labeled mice were implanted with Platelet Derived Growth Factor-BB (PDGF-BB) and basic Fibroblast Growth Factor (FGF-2) containing PEG-based hydrogels in a modified mouse corneal angiogenesis assay. Resulting vessels were imaged with confocal microscopy, analyzed with the image based tool created in this thesis to compare morphological differences between treatment groups, and used to create a linear relationship between space filling parameters and dose of growth factor release. Morphological parameters of native mouse tissue vessels were then compared to the linear fit to calculate the dose of growth factors needed to induce vessels similar in morphology to native vessels

  13. Acetylcholinesterase in blood vessels of the guinea-pig ovary during different phases of the reproductive cycle.

    PubMed

    Silver, A

    1977-05-01

    The distribution of acetylcholinesterase-containing blood vessels in the ovary has been investigated histochemically during the reproductive cycle of the guinea-pig. Whole mounts as well as frozen sections have been studied. Stained vessels were found in the stroma throughout the oestrous cycle and pregnancy. In the corpus luteum the vascular reaction varied at different stages of the oestrous cycle; while never very pronounced, it was more marked in lactating than in non-lactating animals. A feregnancy advanced an increasing number of vessels were strongly stained. At the end of pregnancy, stained vessels were less prominent. Acetylcholinesterase appeared to be localized prinicipally in the vessels themselves (possibly in muscle cells) rather than in associated nerves. Experiments in which ovaries were injected, via their arterial or venous supply, with starch or coloured gelatine suggested that most stained vessels were arterioles but a reaction also occurred in some vessels which were probably arteries and others which could have been the postulated arterio-venous shunts. Capillaries were unstained; whether the veins were also totally unreactive could not be established. The significance of the changes in acetylcholinesterase staining in varying functional states remains obscure; they may or may not reflect the emergence of certain types of vessel at different stages.

  14. A survey of trauma registrars: job requirements, responsibilities, recruitment, and retention.

    PubMed

    Day, Suzanne; Fox, Jolene; Cookman, Kathy

    2012-01-01

    Study purpose was to describe trauma registrar job requirements, responsibilities, and recruitment/retention practices. An online survey was used. One-third required a high school diploma; two-thirds required a college degree. Most required skills were medical terminology (66%), database management (65%), anatomy (64%), Word (63%). Data responsibilities included abstracting, entry, coding, and validating. Few employers required certification. Twenty-six percent reported problems with recruitment, and 35% with retention. Salary and lack of advancement were primary reasons for employee turnover. Certifications were less relevant than skills; the primary focus was data management. Recommendations for recruitment/retention include job flexibility, educational opportunities, and recognition as a profession.

  15. Reducing Inequality in Higher Education: The Link between Faculty Empowerment and Climate and Retention

    ERIC Educational Resources Information Center

    Taylor, Lori L.; Beck, Molly I.; Lahey, Joanna N.; Froyd, Jeffrey E.

    2017-01-01

    Since 2001 the National Science Foundation's ADVANCE program has distributed over $130 million in grants to improve work climate, enhance professional success, and increase recruitment and retention of female faculty in STEM fields. The process by which each institution designs and implements these interventions is seldom studied, however. Using…

  16. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63... BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s) and vessel(s) are interchangeable or synonymous words, and include every description of watercraft...

  17. TECHcitement: Advances in Technology Education, 2008

    ERIC Educational Resources Information Center

    Patton, Madeline

    2008-01-01

    This publication presents the following articles: (1) Advanced Technological Education (ATE) Develops Student Recruitment and Retention Strategies; (2) Marketer Advises Tech Educators Appeal to Teens' Emotions, Desires to Do Something Important; (3) Digital Bridge Academy Gets At-Risk Students on Paths to Knowledge-Based Careers; (4) Project…

  18. Primo vessel inside a lymph vessel emerging from a cancer tissue.

    PubMed

    Lee, Sungwoo; Ryu, Yeonhee; Cha, Jinmyung; Lee, Jin-Kyu; Soh, Kwang-Sup; Kim, Sungchul; Lim, Jaekwan

    2012-10-01

    Primo vessels were observed inside the lymph vessels near the caudal vena cava of a rabbit and a rat and in the thoracic lymph duct of a mouse. In the current work we found a primo vessel inside the lymph vessel that came out from the tumor tissue of a mouse. A cancer model of a nude mouse was made with human lung cancer cell line NCI-H460. We injected fluorescent nanoparticles into the xenografted tumor tissue and studied their flow in blood, lymph, and primo vessels. Fluorescent nanoparticles flowed through the blood vessels quickly in few minutes, and but slowly in the lymph vessels. The bright fluorescent signals of nanoparticles disappeared within one hour in the blood vessels but remained much longer up to several hours in the case of lymph vessels. We found an exceptional case of lymph vessels that remained bright with fluorescence up to 24 hours. After detailed examination we found that the bright fluorescence was due to a putative primo vessel inside the lymph vessel. This rare observation is consistent with Bong-Han Kim's claim on the presence of a primo vascular system in lymph vessels. It provides a significant suggestion on the cancer metastasis through primo vessels and lymph vessels. Copyright © 2012. Published by Elsevier B.V.

  19. Round window electrode insertion potentiates retention in the scala tympani.

    PubMed

    Connor, Stephen E J; Holland, N Julian; Agger, Andreas; Leong, Annabelle C; Varghese, Re Ajay; Jiang, Dan; Fitzgerald O'Connor, Alec

    2012-09-01

    The round window membrane (RWM)-intentioned approach is superior to the traditional bony cochleostomy (BC) approach in obtaining electrode placement within the scala tympani (ST). Cochlear implant outcome is influenced by several factors, including optimal placement and retention of the electrode array within the ST. The present study aimed to assess whether the RWM route is superior to a traditional BC for placement and retention of the electrode array in the ST. This was a prospective consecutive non-randomized comparison study. All patients were implanted with the Advanced Bionics 1J electrode array. The RWM approach (n = 32) was compared with a traditional BC group (n = 33). The outcome measure was the electrode position as judged within the scalar chambers at four points along the basal turn using postoperative computed tomography (CT). When the mean position scores were compared, the RWM-intentioned group had significantly more electrodes directed towards the ST compartment than the BC group (p < 0.001). The RWM electrodes achieved 94% ST retention compared with 64% for the BC group (p < 0.05). All electrodes stayed in the ST in the RWM group, whereas in the BC group 9% crossed from the ST to the scala vestibuli.

  20. Coarse Particulate Organic Matter: Storage, Transport, and Retention

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tiegs, Scott; Lamberti, Gary A.; Entrekin, Sally A.

    2017-08-01

    Coarse particulate organic matter, or CPOM, is a basal energy and nutrient resource in many stream ecosystems and is provided by inputs from the riparian zone, incoming tributaries, and to a lesser extent from in-stream production. The ability of a stream to retain CPOM or slow its transport is critical to its consumption and assimilation by stream biota. In this chapter, we describe basic exercises to measure (1) the amount of CPOM in the streambed and (2) the retention of CPOM from standardized particle releases. We further describe advanced exercises that (1) experimentally enhance the retentiveness of a stream reachmore » and (2) measure organic carbon transport and turnover (i.e., spiraling) in the channel.« less

  1. Coarse Particulate Organic Matter: Storage, Transport, and Retention

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tiegs, Scott; Lamberti, Gary A.; Entrekin, Sally A.

    Coarse particulate organic matter, or CPOM, is a basal energy and nutrient resource in many stream ecosystems and is provided by inputs from the riparian zone, incoming tributaries, and to a lesser extent from in-stream production. The ability of a stream to retain CPOM or slow its transport is critical to its consumption and assimilation by stream biota. In this chapter, we describe basic exercises to measure (1) the amount of CPOM in the streambed and (2) the retention of CPOM from standardized particle releases. We further describe advanced exercises that (1) experimentally enhance the retentiveness of a stream reachmore » and (2) measure organic carbon transport and turnover (i.e., spiraling) in the channel.« less

  2. Recent advances in vibro-impact dynamics and collision of ocean vessels

    NASA Astrophysics Data System (ADS)

    Ibrahim, Raouf A.

    2014-11-01

    The treatment of ship impacts and collisions takes different approaches depending on the emphasis of each discipline. For example, dynamicists, physicist, and mathematicians are dealing with developing analytical models and mappings of vibro-impact systems. On the other hand, naval architects and ship designers are interested in developing design codes and structural assessments due to slamming loads, liquid sloshing impact loads in liquefied natural gas tanks and ship grounding accidents. The purpose of this review is to highlight the main differences of the two disciplines. It begins with a brief account of the theory of vibro-impact dynamics based on modeling and mapping of systems experiencing discontinuous changes in their state of motion due to collision. The main techniques used in modeling include power-law phenomenological modeling, Hertzian modeling, and non-smooth coordinate transformations originally developed by Zhuravlev and Ivanov. In view of their effectiveness, both Zhuravlev and Ivanov non-smooth coordinate transformations will be described and assessed for the case of ship roll dynamics experiencing impact with rigid barriers. These transformations have the advantage of converting the vibro-impact oscillator into an oscillator without barriers such that the corresponding equation of motion does not contain any impact term. One of the recent results dealing with the coefficient of restitution is that its value monotonically decreases with the impact velocity and not unique but random in nature. Slamming loads and grounding events of ocean waves acting on the bottom of high speed vessels will be assessed with reference to the ship structural damage. It will be noticed that naval architects and marine engineers are treating these problems using different approaches from those used by dynamicists. The problem of sloshing impact in liquefied natural gas cargo and related problems will be assessed based on the numerical and experimental results. It is

  3. Engineering blood vessels through micropatterned co-culture of vascular endothelial and smooth muscle cells on bilayered electrospun fibrous mats with pDNA inoculation.

    PubMed

    Liu, Yaowen; Lu, Jinfu; Li, Huinan; Wei, Jiaojun; Li, Xiaohong

    2015-01-01

    Although engineered blood vessels have seen important advances during recent years, proper mechanical strength and vasoactivity remain unsolved problems. In the current study, micropatterned fibrous mats were created to load smooth muscle cells (SMC), and a co-culture with endothelial cells (EC) was established through overlaying on an EC-loaded flat fibrous mat to mimic the layered structure of a blood vessel. A preferential distribution of SMC was determined in the patterned regions throughout the fibrous scaffolds, and aligned fibers in the patterned regions provided topological cues to guide the orientation of SMC with intense actin filaments and extracellular matrix (ECM) production in a circumferential direction. Plasmid DNA encoding basic fibroblast growth factors and vascular endothelial growth factor were integrated into electrospun fibers as biological cues to promote SMC infiltration into fibrous mats, and the viability and ECM production of both EC and SMC. The layered fibrous mats with loaded EC and SMC were wrapped into a cylinder, and engineered vessels were obtained with compact EC and SMC layers after co-culture for 3 months. Randomly oriented ECM productions of EC formed a continuous endothelium covering the entire lumenal surface, and a high alignment of ECM was shown in the circumferential direction of SMC layers. The tensile strength, strain at failure and suture retention strength were higher than those of the human femoral artery, and the burst pressure and radial compliance were in the same range as the human saphenous vein, indicating potential as blood vessel substitutes for transplantation in vivo. Thus, the establishment of topographical cues and biochemical signals in fibrous scaffolds demonstrates advantages in modulating cellular behavior and organization found in complex multicellular tissues. Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  4. 46 CFR 356.45 - Advance of funds.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Advance of funds. 356.45 Section 356.45 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION MISCELLANEOUS REQUIREMENTS FOR VESSELS OF 100 FEET OR GREATER IN REGISTERED LENGTH TO OBTAIN A FISHERY ENDORSEMENT TO THE VESSEL'S DOCUMENTATION Charters...

  5. Tumor Vessel Compression Hinders Perfusion of Ultrasonographic Contrast Agents1

    PubMed Central

    Galiè, Mirco; D'Onofrio, Mirko; Montani, Maura; Amici, Augusto; Calderan, Laura; Marzola, Pasquina; Benati, Donatella; Merigo, Flavia; Marchini, Cristina; Sbarbati, Andrea

    2005-01-01

    Abstract Contrast-enhanced ultrasound (CEUS) is an advanced approach to in vivo assessment of tumor vascularity and is being increasingly adopted in clinical oncology. It is based on 1- to 10 µm-sized gas microbubbles, which can cross the capillary beds of the lungs and are effective echo enhancers. It is known that high cell density, high transendothelial fluid exchange, and poorly functioning lymphatic circulation all provoke solid stress, which compresses vessels and drastically reduces tumor blood flow. Given their size, we supposed that the perfusion of microbubbles is affected by anatomic features of tumor vessels more than are contrast agents traditionally used in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Here, we compared dynamic information obtained from CEUS and DCE-MRI on two experimental tumor models exhibiting notable differences in vessel anatomy. We found that tumors with small, flattened vessels show a much higher resistance to microbubble perfusion than to MRI contrast agents, and appear scarcely vascularized at CEUS examination, despite vessel volume adequate for normal function. Thus, whereas CEUS alone could induce incorrect diagnosis when tumors have small or collapsed vessels, integrated analysis using CEUS and DCE-MRI allows in vivo identification of tumors with a vascular profile frequently associated with malignant phenotypes. PMID:15967105

  6. Neural guidance molecules regulate vascular remodeling and vessel navigation.

    PubMed

    Eichmann, Anne; Makinen, Taija; Alitalo, Kari

    2005-05-01

    The development of the embryonic blood vascular and lymphatic systems requires the coordinated action of several transcription factors and growth factors that target endothelial and periendothelial cells. However, according to recent studies, the precise "wiring" of the vascular system does not occur without an ordered series of guidance decisions involving several molecules initially discovered for axons in the nervous system, including ephrins, netrins, slits, and semaphorins. Here, we summarize the new advances in our understanding of the roles of these axonal pathfinding molecules in vascular remodeling and vessel guidance, indicating that neuronal axons and vessel sprouts use common molecular mechanisms for navigation in the body.

  7. Tracking Vessels to Illegal Pollutant Discharges Using Multisource Vessel Information

    NASA Astrophysics Data System (ADS)

    Busler, J.; Wehn, H.; Woodhouse, L.

    2015-04-01

    Illegal discharge of bilge waters is a significant source of oil and other environmental pollutants in Canadian and international waters. Imaging satellites are commonly used to monitor large areas to detect oily discharges from vessels, off-shore platforms and other sources. While remotely sensed imagery provides a snap-shot picture useful for detecting a spill or the presence of vessels in the vicinity, it is difficult to directly associate a vessel to an observed spill unless the vessel is observed while the discharge is occurring. The situation then becomes more challenging with increased vessel traffic as multiple vessels may be associated with a spill event. By combining multiple sources of vessel location data, such as Automated Information Systems (AIS), Long Range Identification and Tracking (LRIT) and SAR-based ship detection, with spill detections and drift models we have created a system that associates detected spill events with vessels in the area using a probabilistic model that intersects vessel tracks and spill drift trajectories in both time and space. Working with the Canadian Space Agency and the Canadian Ice Service's Integrated Satellite Tracking of Pollution (ISTOP) program, we use spills observed in Canadian waters to demonstrate the investigative value of augmenting spill detections with temporally sequenced vessel and spill tracking information.

  8. Proactive life extension of pressure vessels

    NASA Astrophysics Data System (ADS)

    Mager, Lloyd

    1998-03-01

    For a company to maintain its competitive edge in today's global market every opportunity to gain an advantage must be exploited. Many companies are strategically focusing on improved utilization of existing equipment as well as regulatory compliance. Abbott Laboratories is no exception. Pharmaceutical companies such as Abbott Laboratories realize that reliability and availability of their production equipment is critical to be successful and competitive. Abbott Laboratories, like many of our competitors, is working to improve safety, minimize downtime and maximize the productivity and efficiency of key production equipment such as the pressure vessels utilized in our processes. The correct strategy in obtaining these objectives is to perform meaningful inspection with prioritization based on hazard analysis and risk. The inspection data gathered in Abbott Laboratories pressure vessel program allows informed decisions leading to improved process control. The results of the program are reduced risks to the corporation and employees when operating pressure retaining equipment. Accurate and meaningful inspection methods become the cornerstone of a program allowing proper preventative maintenance actions to occur. Successful preventative/predictive maintenance programs must utilize meaningful nondestructive evaluation techniques and inspection methods. Nondestructive examination methods require accurate useful tools that allow rapid inspection for the entire pressure vessel. Results from the examination must allow the owner to prove compliance of all applicable regulatory laws and codes. At Abbott Laboratories the use of advanced NDE techniques, primarily B-scan ultrasonics, has provided us with the proper tools allowing us to obtain our objectives. Abbott Laboratories uses B-scan ultrasonics utilizing a pulse echo pitch catch technique to provide essential data on our pressure vessels. Equipment downtime is reduced because the nondestructive examination usually takes

  9. Faculty Peer Networks: Role and Relevance in Advancing Agency and Gender Equity

    ERIC Educational Resources Information Center

    O'Meara, KerryAnn; Stromquist, Nelly P.

    2015-01-01

    Organisational efforts to alter gender asymmetries are relatively rare, yet they are taking place in a number of universities. In the USA, sponsored by the National Science Foundation, ADVANCE programmes implement a number of interventions to improve the recruitment, retention, and advancement of women faculty. This study focused on one common…

  10. Outcomes After En Bloc Iliac Vessel Excision and Reconstruction During Pelvic Exenteration.

    PubMed

    Brown, Kilian G M; Koh, Cherry E; Solomon, Michael J; Qasabian, Raffi; Robinson, David; Dubenec, Steven

    2015-09-01

    Advanced pelvic cancers involving the lateral pelvic compartment, and particularly the iliac vasculature, are difficult to manage. Common or external iliac vessel involvement has traditionally been considered a contraindication for curative surgery. The purpose of this study was to investigate pathological and surgical outcomes, particularly postoperative morbidity of pelvic exenteration with en bloc major iliac vascular excision and reconstruction. This study was a case series. The study was conducted at a quaternary referral center for pelvic exenteration in Sydney. Patients included those undergoing en bloc iliac vessel excision as part of their pelvic exenteration for a locally advanced pelvic malignancy. Over the study period, 336 patients underwent pelvic exenteration. Twenty-one patients (6.3%) underwent en bloc vascular excision of 29 vessels for tumor involvement. Twenty-four vessels required reconstruction. The primary outcomes were postoperative complications and pathologic outcomes. Survival rates were estimated using the Kaplan-Meier technique. Operating time for patients who underwent vascular excision and reconstruction was longer, but this did not reach significance (631 vs 531 minutes; p = 0.052). Mean blood loss was significantly higher in the vascular excision and reconstruction group (6.8 vs 3.4 L; p < 0.001). Patients who required en bloc vascular excision were less likely to have R0 margins compared with patients who did not (38% vs 78%; p < 0.001). There was no intraoperative or 30-day mortality. Overall graft patency and limb loss at 1 year were 96% and 0%. A total of 52% of patients had at least 1 vascular related complication. Median overall and disease-free survival times were 34 and 26 months. This study is limited by a relatively small number of heterogeneous patients. En bloc vascular resection and reconstruction for contiguous tumor involvement is feasible and safe in selected patients. Advanced pelvic tumors involving iliac vessels

  11. Hypofractionated Image-Guided IMRT in Advanced Pancreatic Cancer With Simultaneous Integrated Boost to Infiltrated Vessels Concomitant With Capecitabine: A Phase I Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Passoni, Paolo, E-mail: passoni.paolo@hsr.it; Reni, Michele; Cattaneo, Giovanni M.

    2013-12-01

    Purpose: To determine the maximum tolerated radiation dose (MTD) of an integrated boost to the tumor subvolume infiltrating vessels, delivered simultaneously with radical dose to the whole tumor and concomitant capecitabine in patients with pretreated advanced pancreatic adenocarcinoma. Methods and Materials: Patients with stage III or IV pancreatic adenocarcinoma without progressive disease after induction chemotherapy were eligible. Patients underwent simulated contrast-enhanced four-dimensional computed tomography and fluorodeoxyglucose-labeled positron emission tomography. Gross tumor volume 1 (GTV1), the tumor, and GTV2, the tumor subvolume 1 cm around the infiltrated vessels, were contoured. GTVs were fused to generate Internal Target Volume (ITV)1 and ITV2.more » Biological tumor volume (BTV) was fused with ITV1 to create the BTV+Internal Target Volume (ITV) 1. A margin of 5/5/7 mm (7 mm in cranium-caudal) was added to BTV+ITV1 and to ITV2 to create Planning Target Volume (PTV) 1 and PTV2, respectively. Radiation therapy was delivered with tomotherapy. PTV1 received a fixed dose of 44.25 Gy in 15 fractions, and PTV2 received a dose escalation from 48 to 58 Gy as simultaneous integrated boost (SIB) in consecutive groups of at least 3 patients. Concomitant chemotherapy was capecitabine, 1250 mg/m{sup 2} daily. Dose-limiting toxicity (DLT) was defined as any treatment-related G3 nonhematological or G4 hematological toxicity occurring during the treatment or within 90 days from its completion. Results: From June 2005 to February 2010, 25 patients were enrolled. The dose escalation on the SIB was stopped at 58 Gy without reaching the MTD. One patient in the 2{sup nd} dose level (50 Gy) had a DLT: G3 acute gastric ulcer. Three patients had G3 late adverse effects associated with gastric and/or duodenal mucosal damage. All patients received the planned dose of radiation. Conclusions: A dose of 44.25 Gy in 15 fractions to the whole tumor with an SIB of 58 Gy to

  12. ORTHODONTIC RETENTION. Studies of retention capacity, cost-effectiveness and long-term stability.

    PubMed

    Tynelius, Gudrun Edman

    2014-01-01

    Retention strategies, cost-effectiveness and long-term stability of treatment outcome are essential aspects of orthodontic treatment planning. The overall aim of this thesis was to compare and evaluate three different retention strategies, with special reference to short- and long-term clinical stability and cost-effectiveness. The approach was evidence-based, hence randomized controlled methodology was used in order to generate high levels of evidence. This thesis is based on four studies: Papers I and II are based on randomized controlled trials, evaluating the stability of treatment outcome after one and two years of retention, using three different retention strategies: a maxillary vacuum-formed retainer combined with a mandibular canine-to-canine retainer; a maxillary vacuum-formed retainer combined with stripping of the mandibular anterior teeth and a prefabricated positioner. Paper III presents a cost-minimization analysis of two years of retention treatment. Paper IV is based on a randomized controlled trial documenting the results five years post-retention. The following conclusions were drawn: Papers I and II. From a clinical perspective, asssessment after one year of retention disclosed that the three retention methods were successful in retaining the orthodontic treatment results. After two years of retention, all three retention methods were equally effective in controlling relapse at a clinically acceptable level. Most of the relapse occurred during the first year of retention; only minor or negligible changes were found during the second year. The subjects were grouped according to the level of compliance (excellent or good). After two years of retention there was a negative correlation between growth in body height and relapse of mandibular LII in the group of subjects with excellent compliance. The group with good compliance showed a positive correlation (Paper II, Figure 3). After two years of retention, growth in body height, initial crowding and

  13. VEGF165 Stimulates Vessel Density and Vessel Diameter Differently in Angiogenesis and Lymphangiogenesis

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia; Radhakrishnan, Krishnan; DiCorleto, Paul E.; Leontiev, Dmitry; Anand-Apte, Bela; Albarran, Brian; Farr, Andrew G.

    2005-01-01

    Vascular endothelial growth factor-165 (VEGF(sub 165)) stimulated angiogenesis in the quail chorioallantoic membrane (CAM) by vessel expansion from the capillary network. However, lymphangiogenesis was stimulated by the filopodial guidance of tip cells located on blind-ended lymphatic sprouts. As quantified by fractal/generational branching analysis using the computer code VESGEN, vascular density increased maximally at low VEGF concentrations, and vascular diameter increased most at high VEGF concentrations. Increased vascular density and diameter were statistically independent events (r(sub s), -0.06). By fluorescence immunohistochemistry of VEGF receptors VEGFR-1 and VEGFR-2, alpha smooth muscle actin ((alpha) SMA) and a vascular/lymphatic marker, VEGF(sub 165) increased the density and diameter of sprouting lymphatic vessels guided by tip cells (accompanied by the dissociation of lymphatics from blood vessels). Isolated migratory cells expressing (alpha)SMA were recruited to blood vessels, whereas isolated cells expressing VEGFR-2 were recruited primarily to lymphatics. In conclusion, VEGF(sub 165) increased lymphatic vessel density by lymphatic sprouting, but increased blood vessel density by vascular expansion from the capillary network.

  14. Nursing Student Retention in Associate Degree Nursing Programs Utilizing a Retention Specialist

    ERIC Educational Resources Information Center

    Schrum, Ronna A.

    2014-01-01

    The purpose of this study was to examine specific variables associated with nursing student retention in Associate Degree Nursing (ADN) Programs. Jeffreys (2004) Nursing Undergraduate Retention and Success (NURS) conceptual model provided the framework for this descriptive correlational study. One hundred sixty eight pre-licensure associate degree…

  15. Intracranial vessel wall imaging for evaluation of steno-occlusive diseases and intracranial aneurysms.

    PubMed

    Brinjikji, Waleed; Mossa-Basha, Mahmud; Huston, John; Rabinstein, Alejandro A; Lanzino, Giuseppe; Lehman, Vance T

    2017-03-01

    Cerebrovascular diseases have traditionally been classified, diagnosed and managed based on their luminal characteristics. However, over the past several years, several advancements in MRI techniques have ushered in high-resolution vessel wall imaging (HR-VWI), enabling evaluation of intracranial vessel wall pathology. These advancements now allow us to differentiate diseases which have a common angiographic appearance but vastly different natural histories (i.e. moyamoya versus atherosclerosis, reversible cerebral vasoconstriction syndrome versus vasculitis, stable versus unstable intracranial aneurysms). In this review, we detail the anatomical, histopathological and imaging characteristics of various intracranial steno-occlusive diseases and types of intracranial aneurysms and describe the role that HR-VWI can play in diagnosis, risk stratification and treatment. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  16. Correlation between active-learning coursework and student retention of core content during advanced pharmacy practice experiences.

    PubMed

    Lucas, Kristy H; Testman, Julie A; Hoyland, Marcella N; Kimble, Angel M; Euler, Mary L

    2013-10-14

    To implement an active-learning approach in a pharmacotherapy course sequence in the second year (P2) and third (P3) year of a doctor of pharmacy (PharmD) program and determine whether the pedagogical changes correlated with retention of core content in the fourth year (P4). Class sessions were transitioned from slides-based lectures to discussion-based active-learning pedagogy. A comprehensive examination was created and administered to assess student retention of therapeutic topics taught. Students demonstrated significantly improved overall scores on questions derived from the active-learning pedagogy used in Pharmacotherapy II and III compared to those derived from Pharmacotherapy I in which content was delivered by lecture. The use of active-learning strategies over lecture-based methods in pharmacotherapy courses resulted in higher retention of core content. Students' performance in areas taught using the discussion-based methodology was superior to that which was taught using lecture-based slide presentations.

  17. Correlation Between Active-Learning Coursework and Student Retention of Core Content During Advanced Pharmacy Practice Experiences

    PubMed Central

    Testman, Julie A.; Hoyland, Marcella N.; Kimble, Angel M.; Euler, Mary L.

    2013-01-01

    Objective. To implement an active-learning approach in a pharmacotherapy course sequence in the second year (P2) and third (P3) year of a doctor of pharmacy (PharmD) program and determine whether the pedagogical changes correlated with retention of core content in the fourth year (P4). Design. Class sessions were transitioned from slides-based lectures to discussion-based active-learning pedagogy. Assessment. A comprehensive examination was created and administered to assess student retention of therapeutic topics taught. Students demonstrated significantly improved overall scores on questions derived from the active-learning pedagogy used in Pharmacotherapy II and III compared to those derived from Pharmacotherapy I in which content was delivered by lecture. Conclusion. The use of active-learning strategies over lecture-based methods in pharmacotherapy courses resulted in higher retention of core content. Students’ performance in areas taught using the discussion-based methodology was superior to that which was taught using lecture-based slide presentations. PMID:24159212

  18. Best-Quality Vessel Identification Using Vessel Quality Measure in Multiple-Phase Coronary CT Angiography.

    PubMed

    Hadjiiski, Lubomir; Liu, Jordan; Chan, Heang-Ping; Zhou, Chuan; Wei, Jun; Chughtai, Aamer; Kuriakose, Jean; Agarwal, Prachi; Kazerooni, Ella

    2016-01-01

    The detection of stenotic plaques strongly depends on the quality of the coronary arterial tree imaged with coronary CT angiography (cCTA). However, it is time consuming for the radiologist to select the best-quality vessels from the multiple-phase cCTA for interpretation in clinical practice. We are developing an automated method for selection of the best-quality vessels from coronary arterial trees in multiple-phase cCTA to facilitate radiologist's reading or computerized analysis. Our automated method consists of vessel segmentation, vessel registration, corresponding vessel branch matching, vessel quality measure (VQM) estimation, and automatic selection of best branches based on VQM. For every branch, the VQM was calculated as the average radial gradient. An observer preference study was conducted to visually compare the quality of the selected vessels. 167 corresponding branch pairs were evaluated by two radiologists. The agreement between the first radiologist and the automated selection was 76% with kappa of 0.49. The agreement between the second radiologist and the automated selection was also 76% with kappa of 0.45. The agreement between the two radiologists was 81% with kappa of 0.57. The observer preference study demonstrated the feasibility of the proposed automated method for the selection of the best-quality vessels from multiple cCTA phases.

  19. Variabilities detected by acoustic emission from filament-wound Aramid fiber/epoxy composite pressure vessels

    NASA Technical Reports Server (NTRS)

    Hamstad, M. A.

    1978-01-01

    Two hundred and fifty Aramid fiber/epoxy pressure vessels were filament-wound over spherical aluminum mandrels under controlled conditions typical for advanced filament-winding. A random set of 30 vessels was proof-tested to 74% of the expected burst pressure; acoustic emission data were obtained during the proof test. A specially designed fixture was used to permit in situ calibration of the acoustic emission system for each vessel by the fracture of a 4-mm length of pencil lead (0.3 mm in diameter) which was in contact with the vessel. Acoustic emission signatures obtained during testing showed larger than expected variabilities in the mechanical damage done during the proof tests. To date, identification of the cause of these variabilities has not been determined.

  20. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...

  1. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...

  2. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...

  3. 46 CFR 42.05-63 - Ship(s) and vessel(s).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Ship(s) and vessel(s). 42.05-63 Section 42.05-63 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA Definition of Terms Used in This Subchapter § 42.05-63 Ship(s) and vessel(s). The terms ship(s...

  4. Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study

    PubMed Central

    Rudyanto, Rina D.; Kerkstra, Sjoerd; van Rikxoort, Eva M.; Fetita, Catalin; Brillet, Pierre-Yves; Lefevre, Christophe; Xue, Wenzhe; Zhu, Xiangjun; Liang, Jianming; Öksüz, İlkay; Ünay, Devrim; Kadipaşaogandcaron;lu, Kamuran; Estépar, Raúl San José; Ross, James C.; Washko, George R.; Prieto, Juan-Carlos; Hoyos, Marcela Hernández; Orkisz, Maciej; Meine, Hans; Hüllebrand, Markus; Stöcker, Christina; Mir, Fernando Lopez; Naranjo, Valery; Villanueva, Eliseo; Staring, Marius; Xiao, Changyan; Stoel, Berend C.; Fabijanska, Anna; Smistad, Erik; Elster, Anne C.; Lindseth, Frank; Foruzan, Amir Hossein; Kiros, Ryan; Popuri, Karteek; Cobzas, Dana; Jimenez-Carretero, Daniel; Santos, Andres; Ledesma-Carbayo, Maria J.; Helmberger, Michael; Urschler, Martin; Pienn, Michael; Bosboom, Dennis G.H.; Campo, Arantza; Prokop, Mathias; de Jong, Pim A.; Ortiz-de-Solorzano, Carlos; Muñoz-Barrutia, Arrate; van Ginneken, Bram

    2016-01-01

    The VESSEL12 (VESsel SEgmentation in the Lung) challenge objectively compares the performance of different algorithms to identify vessels in thoracic computed tomography (CT) scans. Vessel segmentation is fundamental in computer aided processing of data generated by 3D imaging modalities. As manual vessel segmentation is prohibitively time consuming, any real world application requires some form of automation. Several approaches exist for automated vessel segmentation, but judging their relative merits is difficult due to a lack of standardized evaluation. We present an annotated reference dataset containing 20 CT scans and propose nine categories to perform a comprehensive evaluation of vessel segmentation algorithms from both academia and industry. Twenty algorithms participated in the VESSEL12 challenge, held at International Symposium on Biomedical Imaging (ISBI) 2012. All results have been published at the VESSEL12 website http://vessel12.grand-challenge.org. The challenge remains ongoing and open to new participants. Our three contributions are: (1) an annotated reference dataset available online for evaluation of new algorithms; (2) a quantitative scoring system for objective comparison of algorithms; and (3) performance analysis of the strengths and weaknesses of the various vessel segmentation methods in the presence of various lung diseases. PMID:25113321

  5. Understanding microwave vessel contamination by chloride species.

    PubMed

    Recchia, Sandro; Spanu, Davide; Bianchi, Davide; Dossi, Carlo; Pozzi, Andrea; Monticelli, Damiano

    2016-10-01

    Microwaves are widely used to assist digestion, general sample treatment and synthesis. The use of aqua regia is extensively adopted for the closed vessel mineralization of samples prior to trace element detection, leading to the contamination of microwave vessels by chlorine containing species. The latter are entrapped in the polymeric matrix of the vessels, leading to memory effects that are difficult to remove, among which the risk of silver incomplete recoveries by removal of the sparingly soluble chloride is the predominant one. In the present paper, we determined by mass spectrometry that hydrogen chloride is the species entrapped in the polymeric matrix and responsible for vessel contamination. Moreover, several decontamination treatments were considered to assess their efficiency, demonstrating that several cleaning cycles with water, nitric acid or silver nitrate in nitric acid were inefficient in removing chloride contamination (contamination reduction around 90%). Better results (≈95% decrease) were achieved by a single decontamination step in alkaline environment (sodium hydroxide or ammonia). Finally, a thermal treatment in a common laboratory oven (i.e. without vacuum and ventilation) was tested: a one hour heating at 150°C leads to a 98.5% decontamination, a figure higher than the ones obtained by wet treatments which requires comparable time. The latter treatment is a major advancement with respect to existing treatments as it avoids the need of a vacuum oven for at least 17h as presently proposed in the literature. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Modification on liquid retention property of cassava starch by radiation grafting with acrylonitrile. I. Effect of γ-irradiation on grafting parameters

    NASA Astrophysics Data System (ADS)

    Kiatkamjornwong, S.; Chvajarernpun, J.; Nakason, C.

    1993-07-01

    Radiation modification on liquid retention properties of native cassava starch, gelatinized at 85°C, by graft copolymerization with acrylonitrile was carried out by mutual irradiation to gamma-rays. A thin aluminum foil was used to cover the inner wall of the reaction vessel, so that the homopolymer concentration was reduced to be less than 1.0% with a distilled water retention value of 665 g/g of the dry weight of the saponified grafted product. Confirmation of graft copolymerization and saponification reactions was made by the infrared spectrophotometric technique. The combined effect of radiation parameters in terms of an irradiation time and a dose rate to the total dose on the extent of the grafting reaction expressed in terms of grafting parameters which directly influenced liquid retention values was evaluated in conjunction with statistical analysis.

  7. Estrogen receptor expression and vessel density in the vagina wall in postmenopausal women with prolapse.

    PubMed

    Lara, Lúcia Alves da Silva; Ribeiro da Silva, Alfredo; Rosa-e-Silva, Julio Cesar; Silva-de-Sá, Marcos Felipe; Rosa-e-Silva, Ana Carolina Japur de Sá

    2014-04-01

    After menopause, critically estrogen low levels result in modifications in vaginal wall. This cross-sectional study aims to determine whether there is a change in the number of vessels in the lamina propria of the vagina after menopause in parallel to the ER-alpha expression on the vaginal wall. Twelve women who underwent a genital surgery for genital prolapse up to grade II were selected. They were divided into two groups: a premenopausal group (PG) consisting of six women who were 18-40 years old with FSH levels =12 mIU/ml and regular cycles, and a menopausal group (MG) consisting of six women at least one year after menopause who were <65 years old with FSH levels =40 mIU/ml. Slides were stained for ER-alpha immunohistochemistry, and an endothelial cell marker CD3 was used to label vessels which were identified by using a system for morphometry. The number of vessels was significantly higher in the PG than in the MG both on the anterior wall (PG: 1.055 ± 145.8 vessels/mm(2), MG: 346.6 ± 209.9 vessels/mm(2), p<0.0001) and on the posterior wall (PG: 1064 ± 303.3 vessels/mm(2), MG: 348.6 ± 167.3 vessels/mm(2), p=0.0005). The ER-alpha score was significantly higher in the PG than the score for the MG on both the anterior and posterior walls (PG: 6.0 ± 0.52, MG: 2.5 ± 0.89, p=0.007; PG: 5.8 ± 0.79, MG: 2.7 ± 0.95, p=0.03, respectively). There was a positive correlation between the ER-alpha score and the vessel concentration on the anterior (r=0.6656, p=0.018) and posterior (r=0.6738, p=0.016) vaginal walls. Age was strongly negatively correlated with vessel concentration on the vaginal walls (respectively r=-0.9033, p<0.0001, r=-0.7440, p=0.0055). Therefore, postmenopausal women with genital prolapse have a smaller number of vessels on the vaginal wall compared to normoestrogenic controls with the same pathological condition. Hypoestrogenism and advancing age are factors that are associated to these changes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Vesselness propagation: a fast interactive vessel segmentation method

    NASA Astrophysics Data System (ADS)

    Cai, Wenli; Dachille, Frank; Harris, Gordon J.; Yoshida, Hiroyuki

    2006-03-01

    With the rapid development of multi-detector computed tomography (MDCT), resulting in increasing temporal and spatial resolution of data sets, clinical use of computed tomographic angiography (CTA) is rapidly increasing. Analysis of vascular structures is much needed in CTA images; however, the basis of the analysis, vessel segmentation, can still be a challenging problem. In this paper, we present a fast interactive method for CTA vessel segmentation, called vesselness propagation. This method is a two-step procedure, with a pre-processing step and an interactive step. During the pre-processing step, a vesselness volume is computed by application of a CTA transfer function followed by a multi-scale Hessian filtering. At the interactive stage, the propagation is controlled interactively in terms of the priority of the vesselness. This method was used successfully in many CTA applications such as the carotid artery, coronary artery, and peripheral arteries. It takes less than one minute for a user to segment the entire vascular structure. Thus, the proposed method provides an effective way of obtaining an overview of vascular structures.

  9. A biomimetic microfluidic chip to study the circulation and mechanical retention of red blood cells in the spleen.

    PubMed

    Picot, Julien; Ndour, Papa Alioune; Lefevre, Sophie D; El Nemer, Wassim; Tawfik, Harvey; Galimand, Julie; Da Costa, Lydie; Ribeil, Jean-Antoine; de Montalembert, Mariane; Brousse, Valentine; Le Pioufle, Bruno; Buffet, Pierre; Le Van Kim, Caroline; Français, Olivier

    2015-04-01

    Red blood cells (RBCs) are deformable and flow through vessels narrower than their own size. Their deformability is most stringently challenged when they cross micrometer-wide slits in the spleen. In several inherited or acquired RBC disorders, blockade of small vessels by stiff RBCs can trigger organ damage, but a functional spleen is expected to clear these abnormal RBCs from the circulation before they induce such complications. We analyzed flow behavior of RBCs in a microfluidic chip that replicates the mechanical constraints imposed on RBCs as they cross the human spleen. Polymer microchannels obtained by soft lithography with a hydraulic diameter of 25 μm drove flow into mechanical filtering units where RBCs flew either slowly through 5- to 2-μm-wide slits or rapidly along 10-μm-wide channels, these parallel paths mimicking the splenic microcirculation. Stiff heated RBCs accumulated in narrow slits seven times more frequently than normal RBCs infused simultaneously. Stage-dependent retention of Plasmodium falciparum-infected RBCs was also observed in these slits. We also analyzed RBCs from patients with hereditary spherocytosis and observed retention for those having the most altered mechanical properties as determined by ektacytometry. Thus, in keeping with previous observations in vivo and ex vivo, the chip successfully discriminated poorly deformable RBCs based on their distinct mechanical properties and on the intensity of the cell alteration. Applications to the exploration of the pathogenesis of malaria, hereditary spherocytosis, sickle cell disease and other RBC disorders are envisioned. © 2015 Wiley Periodicals, Inc.

  10. Fecal retention in childhood: Evaluation on ultrasonography.

    PubMed

    Hatori, Reiko; Tomomasa, Takeshi; Ishige, Takashi; Tatsuki, Maiko; Arakawa, Hirokazu

    2017-04-01

    To assess the usefulness of rectal diameter measurement on ultrasonography as a diagnostic tool for fecal retention in children. One hundred children (median age, 5.0 years), consisting of 80 with functional constipation and 20 without constipation, participated in the study. All patients underwent physical examination that included digital rectal examination. Forty-five children underwent ultrasonography in three differential planes: transection above the symphysis; under the ischial spine; and at the bladder neck. The measurement of the rectal diameter at the transection above the symphysis could most easily detect fecal retention and had the closest correlations with retention among the three planes. Rectal diameter was wider at all measuring points (35.2 vs 20.9 mm above the symphysis, P < 0.0001; 35.7 vs 24.0 mm under the ischial spine, P < 0.0001; and 19.4 vs 8.7 mm at the bladder neck, P < 0.0001) in children with fecal retention than in those with no fecal retention. With regard to presence of constipation, children with fecal retention had a wider rectal diameter above the symphysis than those with no fecal retention (children with functional constipation, 35.3 vs 20.0 mm, P < 0.0001; children without constipation: 32.6 vs 14.6 mm, P = 0.0026). The cut-off for the rectal diameter measured above the symphysis to identify fecal retention was 27 mm, with high sensitivity and specificity (95.5% and 94.1%, respectively). Ultrasound rectal diameter measurement can be used to detect fecal retention in children. © 2016 Japan Pediatric Society.

  11. An automated method for accurate vessel segmentation.

    PubMed

    Yang, Xin; Liu, Chaoyue; Le Minh, Hung; Wang, Zhiwei; Chien, Aichi; Cheng, Kwang-Ting Tim

    2017-05-07

    Vessel segmentation is a critical task for various medical applications, such as diagnosis assistance of diabetic retinopathy, quantification of cerebral aneurysm's growth, and guiding surgery in neurosurgical procedures. Despite technology advances in image segmentation, existing methods still suffer from low accuracy for vessel segmentation in the two challenging while common scenarios in clinical usage: (1) regions with a low signal-to-noise-ratio (SNR), and (2) at vessel boundaries disturbed by adjacent non-vessel pixels. In this paper, we present an automated system which can achieve highly accurate vessel segmentation for both 2D and 3D images even under these challenging scenarios. Three key contributions achieved by our system are: (1) a progressive contrast enhancement method to adaptively enhance contrast of challenging pixels that were otherwise indistinguishable, (2) a boundary refinement method to effectively improve segmentation accuracy at vessel borders based on Canny edge detection, and (3) a content-aware region-of-interests (ROI) adjustment method to automatically determine the locations and sizes of ROIs which contain ambiguous pixels and demand further verification. Extensive evaluation of our method is conducted on both 2D and 3D datasets. On a public 2D retinal dataset (named DRIVE (Staal 2004 IEEE Trans. Med. Imaging 23 501-9)) and our 2D clinical cerebral dataset, our approach achieves superior performance to the state-of-the-art methods including a vesselness based method (Frangi 1998 Int. Conf. on Medical Image Computing and Computer-Assisted Intervention) and an optimally oriented flux (OOF) based method (Law and Chung 2008 European Conf. on Computer Vision). An evaluation on 11 clinical 3D CTA cerebral datasets shows that our method can achieve 94% average accuracy with respect to the manual segmentation reference, which is 23% to 33% better than the five baseline methods (Yushkevich 2006 Neuroimage 31 1116-28; Law and Chung 2008

  12. Hydrogen storage in insulated pressure vessels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Aceves, S.M.; Garcia-Villazana, O.

    1998-08-01

    Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). This paper shows an evaluation of the applicability of the insulated pressure vessels for light-duty vehicles. The paper shows an evaluation of evaporative losses and insulation requirements and a description of the current analysis and experimental plans for testing insulated pressure vessels. The results show significant advantages to the use ofmore » insulated pressure vessels for light-duty vehicles.« less

  13. Fractal Branching in Vascular Trees and Networks by VESsel GENeration Analysis (VESGEN)

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia A.

    2016-01-01

    Vascular patterning offers an informative multi-scale, fractal readout of regulatory signaling by complex molecular pathways. Understanding such molecular crosstalk is important for physiological, pathological and therapeutic research in Space Biology and Astronaut countermeasures. When mapped out and quantified by NASA's innovative VESsel GENeration Analysis (VESGEN) software, remodeling vascular patterns become useful biomarkers that advance out understanding of the response of biology and human health to challenges such as microgravity and radiation in space environments.

  14. Beyond Frangi: an improved multiscale vesselness filter

    NASA Astrophysics Data System (ADS)

    Jerman, Tim; Pernuš, Franjo; Likar, Boštjan; Špiclin, Žiga

    2015-03-01

    Vascular diseases are among the top three causes of death in the developed countries. Effective diagnosis of vascular pathologies from angiographic images is therefore very important and usually relies on segmentation and visualization of vascular structures. To enhance the vascular structures prior to their segmentation and visualization, and to suppress non-vascular structures and image noise, the filters enhancing vascular structures are used extensively. Even though several enhancement filters are widely used, the responses of these filters are typically not uniform between vessels of different radii and, compared to the response in the central part of vessels, their response is lower at vessels' edges and bifurcations, and vascular pathologies like aneurysm. In this paper, we propose a novel enhancement filter based on ratio of multiscale Hessian eigenvalues, which yields a close-to-uniform response in all vascular structures and accurately enhances the border between the vascular structures and the background. The proposed and four state-of-the-art enhancement filters were evaluated and compared on a 3D synthetic image containing tubular structures and a clinical dataset of 15 cerebral 3D digitally subtracted angiograms with manual expert segmentations. The evaluation was based on quantitative metrics of segmentation performance, computed as area under the precision-recall curve, signal-to-noise ratio of the vessel enhancement and the response uniformity within vascular structures. The proposed filter achieved the best scores in all three metrics and thus has a high potential to further improve the performance of existing or encourage the development of more advanced methods for segmentation and visualization of vascular structures.

  15. Retention of indigenous nursing students in New Zealand: a cross-sectional survey.

    PubMed

    Wilson, Denise; McKinney, Caroline; Rapata-Hanning, Mereana

    2011-01-01

    Internationally the recruitment and retention of Indigenous and minority peoples into nursing is a persistent challenge, despite their participation being essential in reducing health disparities and improving health service quality for Indigenous and minority users. We aimed to identify Māori (Indigenous to New Zealand) nursing students' experiences of undertaking a nursing degree program. A non-experimental cross-sectional survey was undertaken with undergraduate nursing students identifying as Māori. The surveys were analyzed using descriptive and inferential statistics. One hundred and eight students responded, with a career, stable income, and desire to make a difference in Māori health outcomes motivating most to embark on a nursing program. They reported numerous obstacles that compromised their academic advancement. However, affirming students' identities; providing academic support; accessing Indigenous role models, mentors and relevant clinical experiences; and, having supportive teaching and learning environments and the inclusion of Indigenous content in curricula; were identified as strategies that promoted retention in nursing programs.

  16. Co-option of Liver Vessels and Not Sprouting Angiogenesis Drives Acquired Sorafenib Resistance in Hepatocellular Carcinoma.

    PubMed

    Kuczynski, Elizabeth A; Yin, Melissa; Bar-Zion, Avinoam; Lee, Christina R; Butz, Henriett; Man, Shan; Daley, Frances; Vermeulen, Peter B; Yousef, George M; Foster, F Stuart; Reynolds, Andrew R; Kerbel, Robert S

    2016-08-01

    The anti-angiogenic Sorafenib is the only approved systemic therapy for advanced hepatocellular carcinoma (HCC). However, acquired resistance limits its efficacy. An emerging theory to explain intrinsic resistance to other anti-angiogenic drugs is 'vessel co-option,' ie, the ability of tumors to hijack the existing vasculature in organs such as the lungs or liver, thus limiting the need for sprouting angiogenesis. Vessel co-option has not been evaluated as a potential mechanism for acquired resistance to anti-angiogenic agents. To study sorafenib resistance mechanisms, we used an orthotopic human HCC model (n = 4-11 per group), where tumor cells are tagged with a secreted protein biomarker to monitor disease burden and response to therapy. Histopathology, vessel perfusion assessed by contrast-enhanced ultrasound, and miRNA sequencing and quantitative real-time polymerase chain reaction were used to monitor changes in tumor biology. While sorafenib initially inhibited angiogenesis and stabilized tumor growth, no angiogenic 'rebound' effect was observed during development of resistance unless therapy was stopped. Instead, resistant tumors became more locally infiltrative, which facilitated extensive incorporation of liver parenchyma and the co-option of liver-associated vessels. Up to 75% (±10.9%) of total vessels were provided by vessel co-option in resistant tumors relative to 23.3% (±10.3%) in untreated controls. miRNA sequencing implicated pro-invasive signaling and epithelial-to-mesenchymal-like transition during resistance development while functional imaging further supported a shift from angiogenesis to vessel co-option. This is the first documentation of vessel co-option as a mechanism of acquired resistance to anti-angiogenic therapy and could have important implications including the potential therapeutic benefits of targeting vessel co-option in conjunction with vascular endothelial growth factor receptor signaling. © The Author 2016. Published by

  17. Debulking surgery for elephantiasis nostras with large ectatic podoplanin-negative lymphatic vessels in patients with lipo-lymphedema.

    PubMed

    Wollina, Uwe; Heinig, Birgit; Schönlebe, Jaqueline; Nowak, Andreas

    2014-01-01

    Elephantiasis nostras is a rare complication in advanced lipo-lymphedema. While lipedema can be treated by liposuction and lymphedema by decongestive lymphatic therapy, elephantiasis nostras may need debulking surgery. We present 2 cases of advanced lipo-lymphedema complicated by elephantiasis nostras. After tumescent microcannular laser-assisted liposuction both patients underwent a debulking surgery with a modification of Auchincloss-Kim's technique. Histologic examination of the tissue specimen was performed. The surgical treatment was well tolerated and primary healing was uneventful. After primary wound healing and ambulation of the patients, a delayed ulceration with lymphorrhea developed. It was treated by surgical necrectomy and vacuum-assisted closure leading to complete healing. Mobility of the leg was much improved. Histologic examination revealed massive ectatic lymphatic vessels nonreactive for podoplanin. Debulking surgery can be an adjuvant technique for elephantiasis nostras in advanced lipo-lymphedema. Although delayed postoperative wound healing problems were observed, necrectomy and vacuum-assisted closure achieved a complete healing. Histologic data suggest that the ectatic lymphatic vessels in these patients resemble finding in podoplanin knockout mice. The findings would explain the limitations of decongestive lymphatic therapy and tumescent liposuction in such patients and their predisposition to relapsing erysipelas.

  18. Novel word retention in bilingual and monolingual speakers

    PubMed Central

    Kan, Pui Fong; Sadagopan, Neeraja

    2014-01-01

    The goal of this research was to examine word retention in bilinguals and monolinguals. Long-term word retention is an essential part of vocabulary learning. Previous studies have documented that bilinguals outperform monolinguals in terms of retrieving newly-exposed words. Yet, little is known about whether or to what extent bilinguals are different from monolinguals in word retention. Participants were 30 English-speaking monolingual adults and 30 bilingual adults who speak Spanish as a home language and learned English as a second language during childhood. In a previous study (Kan et al., 2014), the participants were exposed to the target novel words in English, Spanish, and Cantonese. In this current study, word retention was measured a week after the fast mapping task. No exposures were given during the one-week interval. Results showed that bilinguals and monolinguals retain a similar number of words. However, participants produced more words in English than in either Spanish or Cantonese. Correlation analyses revealed that language knowledge plays a role in the relationships between fast mapping and word retention. Specifically, within- and across-language relationships between bilinguals' fast mapping and word retention were found in Spanish and English, by contrast, within-language relationships between monolinguals' fast mapping and word retention were found in English and across-language relationships between their fast mapping and word retention performance in English and Cantonese. Similarly, bilinguals differed from monolinguals in the relationships among the word retention scores in three languages. Significant correlations were found among bilinguals' retention scores. However, no such correlations were found among monolinguals' retention scores. The overall findings suggest that bilinguals' language experience and language knowledge most likely contribute to how they learn and retain new words. PMID:25324789

  19. Novel word retention in bilingual and monolingual speakers.

    PubMed

    Kan, Pui Fong; Sadagopan, Neeraja

    2014-01-01

    The goal of this research was to examine word retention in bilinguals and monolinguals. Long-term word retention is an essential part of vocabulary learning. Previous studies have documented that bilinguals outperform monolinguals in terms of retrieving newly-exposed words. Yet, little is known about whether or to what extent bilinguals are different from monolinguals in word retention. Participants were 30 English-speaking monolingual adults and 30 bilingual adults who speak Spanish as a home language and learned English as a second language during childhood. In a previous study (Kan et al., 2014), the participants were exposed to the target novel words in English, Spanish, and Cantonese. In this current study, word retention was measured a week after the fast mapping task. No exposures were given during the one-week interval. Results showed that bilinguals and monolinguals retain a similar number of words. However, participants produced more words in English than in either Spanish or Cantonese. Correlation analyses revealed that language knowledge plays a role in the relationships between fast mapping and word retention. Specifically, within- and across-language relationships between bilinguals' fast mapping and word retention were found in Spanish and English, by contrast, within-language relationships between monolinguals' fast mapping and word retention were found in English and across-language relationships between their fast mapping and word retention performance in English and Cantonese. Similarly, bilinguals differed from monolinguals in the relationships among the word retention scores in three languages. Significant correlations were found among bilinguals' retention scores. However, no such correlations were found among monolinguals' retention scores. The overall findings suggest that bilinguals' language experience and language knowledge most likely contribute to how they learn and retain new words.

  20. Strategies for Tailoring the Pore-Size Distribution of Virus Retention Filter Papers.

    PubMed

    Gustafsson, Simon; Mihranyan, Albert

    2016-06-08

    The goal of this work is to demonstrate how the pore-size distribution of the nanocellulose-based virus-retentive filter can be tailored. The filter paper was produced using cellulose nanofibers derived from Cladophora sp. green algae using the hot-press drying at varying drying temperatures. The produced filters were characterized using scanning electron microscopy, atomic force microscopy, and N2 gas sorption analysis. Further, hydraulic permeability and retention efficiency toward surrogate 20 nm model particles (fluorescent carboxylate-modified polystyrene spheres) were assessed. It was shown that by controlling the rate of water evaporation during hot-press drying the pore-size distribution can be precisely tailored in the region between 10 and 25 nm. The mechanism of pore formation and critical parameters are discussed in detail. The results are highly valuable for development of advanced separation media, especially for virus-retentive size-exclusion filtration.

  1. Enhanced post wash retention of combed DNA molecules by varying multiple combing parameters.

    PubMed

    Yadav, Hemendra; Sharma, Pulkit

    2017-11-01

    Recent advances in genomics have created a need for efficient techniques for deciphering information hidden in various genomes. Single molecule analysis is one such technique to understand molecular processes at single molecule level. Fiber- FISH performed with the help of DNA combing can help us in understanding genetic rearrangements and changes in genome at single DNA molecule level. For performing Fiber-FISH we need high retention of combed DNA molecules post wash as Fiber-FISH requires profuse washing. We optimized combing process involving combing solution, method of DNA mounting on glass slides and coating of glass slides to enhance post-wash retention of DNA molecules. It was found that average number of DNA molecules observed post-wash per field of view was maximum with our optimized combing solution. APTES coated glass slides showed lesser retention than PEI surface but fluorescent intensity was higher in case of APTES coated surface. Capillary method used to mount DNA on glass slides also showed lesser retention but straight DNA molecules were observed as compared to force flow method. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Heart and Blood Vessels in Marfan Syndrome

    MedlinePlus

    ... The most common of these problems affects the aorta, the main blood vessel carrying blood from the ... have problems in blood vessels other than the aorta. Even though heart and blood vessel problems affect ...

  3. Hydrogen retention in lithium and lithium oxide films

    NASA Astrophysics Data System (ADS)

    Buzi, L.; Yang, Y.; Domínguez-Gutiérrez, F. J.; Nelson, A. O.; Hofman, M.; Krstić, P. S.; Kaita, R.; Koel, B. E.

    2018-04-01

    Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li2O films, measurements were made as a function of surface temperature (90-520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li2O films retained H in similar amounts as pure Li. Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.

  4. 46 CFR 11.305 - Requirements to qualify for an STCW endorsement as master of vessels of 3,000 GT or more...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... gained in the engine department on vessels may be creditable for up to 3 months of the service...) Advanced stability. (iii) Advanced meteorology. (iv) Leadership and managerial skills. (v) Search and...

  5. Fuel nozzle tube retention

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cihlar, David William; Melton, Patrick Benedict

    A system for retaining a fuel nozzle premix tube includes a retention plate and a premix tube which extends downstream from an outlet of a premix passage defined along an aft side of a fuel plenum body. The premix tube includes an inlet end and a spring support feature which is disposed proximate to the inlet end. The premix tube extends through the retention plate. The spring retention feature is disposed between an aft side of the fuel plenum and the retention plate. The system further includes a spring which extends between the spring retention feature and the retention plate.

  6. Probabilistic retinal vessel segmentation

    NASA Astrophysics Data System (ADS)

    Wu, Chang-Hua; Agam, Gady

    2007-03-01

    Optic fundus assessment is widely used for diagnosing vascular and non-vascular pathology. Inspection of the retinal vasculature may reveal hypertension, diabetes, arteriosclerosis, cardiovascular disease and stroke. Due to various imaging conditions retinal images may be degraded. Consequently, the enhancement of such images and vessels in them is an important task with direct clinical applications. We propose a novel technique for vessel enhancement in retinal images that is capable of enhancing vessel junctions in addition to linear vessel segments. This is an extension of vessel filters we have previously developed for vessel enhancement in thoracic CT scans. The proposed approach is based on probabilistic models which can discern vessels and junctions. Evaluation shows the proposed filter is better than several known techniques and is comparable to the state of the art when evaluated on a standard dataset. A ridge-based vessel tracking process is applied on the enhanced image to demonstrate the effectiveness of the enhancement filter.

  7. Boulder Valley Kindergarten Study: Retention Practices and Retention Effects.

    ERIC Educational Resources Information Center

    Shepard, Lorrie A.; Smith, Mary Lee

    Having implemented a policy that allowed schools to retain children in kindergarten an extra year, the Boulder Valley Public School District in Colorado conducted a study to determine the cognitive and emotional benefits of retention in kindergarten and the characteristics that led to decisions about retention. The study involved a research review…

  8. PAR1 signaling regulates the retention and recruitment of EPCR-expressing bone marrow hematopoietic stem cells

    PubMed Central

    Gur-Cohen, Shiri; Itkin, Tomer; Chakrabarty, Sagarika; Graf, Claudine; Kollet, Orit; Ludin, Aya; Golan, Karin; Kalinkovich, Alexander; Ledergor, Guy; Wong, Eitan; Niemeyer, Elisabeth; Porat, Ziv; Erez, Ayelet; Sagi, Irit; Esmon, Charles T; Ruf, Wolfram; Lapidot, Tsvee

    2016-01-01

    Retention of long-term repopulating hematopoietic stem cells (LT-HSCs) in the bone marrow is essential for hematopoiesis and for protection from myelotoxic injury. We report that signaling cascades that are traditionally viewed as coagulation-related also control retention of EPCR+ LT-HSCs in the bone marrow and their recruitment to the blood via two different protease activated receptor 1 (PAR1)-mediated pathways. Thrombin-PAR1 signaling induces nitric oxide (NO) production, leading to TACE-mediated EPCR shedding, enhanced CXCL12-CXCR4-induced motility, and rapid stem and progenitor cell mobilization. Conversely, bone marrow blood vessels provide a microenvironment enriched with protein C that retain EPCR+ LT-HSCs by limiting NO generation, reducing Cdc42 activity and enhancing VLA4 affinity and adhesion. Inhibition of NO production by activated protein C (aPC)-EPCR-PAR1 signaling reduces progenitor cell egress, increases NOlow bone marrow EPCR+ LT-HSCs retention and protects mice from chemotherapy-induced hematological failure and death. Our study reveals new roles for PAR1 and EPCR that control NO production to balance maintenance and recruitment of bone marrow EPCR+ LT-HSCs with clinical relevance. PMID:26457757

  9. A parametric study of helium retention in beryllium and its effect on deuterium retention

    NASA Astrophysics Data System (ADS)

    Alegre, D.; Baldwin, M. J.; Simmonds, M.; Nishijima, D.; Hollmann, E. M.; Brezinsek, S.; Doerner, R. P.

    2017-12-01

    Beryllium samples have been exposed in the PISCES-B linear plasma device to conditions relevant to the International Thermonuclear Experimental Reactor (ITER) in pure He, D, and D/He mixed plasmas. Except at intermediate sample exposure temperatures (573-673 K) He addition to a D plasma is found to have a beneficial effect as it reduces the D retention in Be (up to ˜55%), although the mechanism is unclear. Retention of He is typically around 1020-1021 He m-2, and is affected primarily by the Be surface temperature during exposition, by the ion fluence at <500 K exposure, but not by the ion impact energy at 573 K. Contamination of the Be surface with high-Z elements from the mask of the sample holder in pure He plasmas is also observed under certain conditions, and leads to unexpectedly large He retention values, as well as changes in the surface morphology. An estimation of the tritium retention in the Be first wall of ITER is provided, being sufficiently low to allow a safe operation of ITER.

  10. Vessel discoloration detection in malarial retinopathy

    NASA Astrophysics Data System (ADS)

    Agurto, C.; Nemeth, S.; Barriga, S.; Soliz, P.; MacCormick, I.; Taylor, T.; Harding, S.; Lewallen, S.; Joshi, V.

    2016-03-01

    Cerebral malaria (CM) is a life-threatening clinical syndrome associated with malarial infection. It affects approximately 200 million people, mostly sub-Saharan African children under five years of age. Malarial retinopathy (MR) is a condition in which lesions such as whitening and vessel discoloration that are highly specific to CM appear in the retina. Other unrelated diseases can present with symptoms similar to CM, therefore the exact nature of the clinical symptoms must be ascertained in order to avoid misdiagnosis, which can lead to inappropriate treatment and, potentially, death. In this paper we outline the first system to detect the presence of discolored vessels associated with MR as a means to improve the CM diagnosis. We modified and improved our previous vessel segmentation algorithm by incorporating the `a' channel of the CIELab color space and noise reduction. We then divided the segmented vasculature into vessel segments and extracted features at the wall and in the centerline of the segment. Finally, we used a regression classifier to sort the segments into discolored and not-discolored vessel classes. By counting the abnormal vessel segments in each image, we were able to divide the analyzed images into two groups: normal and presence of vessel discoloration due to MR. We achieved an accuracy of 85% with sensitivity of 94% and specificity of 67%. In clinical practice, this algorithm would be combined with other MR retinal pathology detection algorithms. Therefore, a high specificity can be achieved. By choosing a different operating point in the ROC curve, our system achieved sensitivity of 67% with specificity of 100%.

  11. Predictors of Calcium Retention in Adolescent Boys

    PubMed Central

    Hill, Kathleen M.; Braun, Michelle; Kern, Mark; Martin, Berdine R.; Navalta, James W.; Sedlock, Darlene A.; McCabe, Linda; McCabe, George P.; Peacock, Munro; Weaver, Connie M.

    2008-01-01

    Context: The relationship between calcium (Ca) intake and Ca retention in adolescent boys was recently reported. Objective: This study evaluated the influence of Ca intake, serum hormone levels, biomarkers of bone metabolism, habitual physical activity, habitual Ca intake, and physical fitness on Ca retention in the same sample. Design: This study was a randomized, cross-over design that consisted of two 3-wk metabolic balance periods. Setting: The study took place on a university campus as a summer camp. Patients or Other Participants: A total of 31 American white boys (13–15 yr) participated in the study. Interventions: Each subject consumed a controlled diet with one of five high-low Ca intake pairs that ranged from 670-2003 mg/d, which was manipulated utilizing a fortified beverage. Main Outcome Measures: Ca retention was determined by Ca intake minus urinary and fecal Ca excretion during each balance period. Results: Ca intake explained 21.7% of the variability in Ca retention, and serum IGF-I concentration explained an additional 11.5%. Other serum hormone levels did not significantly add to the model. Biomarkers of bone metabolism, habitual physical activity, habitual Ca intake, and physical fitness were not significant predictors of Ca retention in adolescent boys. Conclusions: IGF-I, a regulator of growth during puberty, is an important predictor of Ca retention in adolescent boys. However, dietary Ca intake is an even greater predictor of Ca retention during this period of growth. PMID:18840643

  12. Hydrogen retention in lithium and lithium oxide films

    DOE PAGES

    Buzi, L.; Yang, Y.; Dominguez-Gutierrez, F. J.; ...

    2018-02-09

    Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li 2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li 2O films, measurements were made as a function of surface temperature (90–520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li 2O films retained Hmore » in similar amounts as pure Li. Finally, Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.« less

  13. Hydrogen retention in lithium and lithium oxide films

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Buzi, L.; Yang, Y.; Dominguez-Gutierrez, F. J.

    Pure lithium (Li) surfaces are difficult to maintain in fusion devices due to rapid oxide formation, therefore, parameterizing and understanding the mechanisms of hydrogen (H, D) retention in lithium oxide (Li 2O) in addition to pure Li is crucial for Li plasma-facing material applications. To compare H retention in Li and Li 2O films, measurements were made as a function of surface temperature (90–520 K) under ultrahigh vacuum (UHV) conditions using temperature programmed desorption (TPD). In both cases, the total retention dropped with surface temperature, from 95% at 90 K to 35% at 520 K Li 2O films retained Hmore » in similar amounts as pure Li. Finally, Molecular Dynamics (MD) modeling was used to elucidate the mechanisms of H retention, and results were consistent with experiments in terms of both retention fraction and the drop of retention with temperature.« less

  14. Advances in Pediatric Cardiology Boot Camp: Boot Camp Training Promotes Fellowship Readiness and Enables Retention of Knowledge.

    PubMed

    Ceresnak, Scott R; Axelrod, David M; Sacks, Loren D; Motonaga, Kara S; Johnson, Emily R; Krawczeski, Catherine D

    2017-03-01

    We previously demonstrated that a pediatric cardiology boot camp can improve knowledge acquisition and decrease anxiety for trainees. We sought to determine if boot camp participants entered fellowship with a knowledge advantage over fellows who did not attend and if there was moderate-term retention of that knowledge. A 2-day training program was provided for incoming pediatric cardiology fellows from eight fellowship programs in April 2016. Hands-on, immersive experiences and simulations were provided in all major areas of pediatric cardiology. Knowledge-based examinations were completed by each participant prior to boot camp (PRE), immediately post-training (POST), and prior to the start of fellowship in June 2016 (F/U). A control group of fellows who did not attend boot camp also completed an examination prior to fellowship (CTRL). Comparisons of scores were made for individual participants and between participants and controls. A total of 16 participants and 16 control subjects were included. Baseline exam scores were similar between participants and controls (PRE 47 ± 11% vs. CTRL 52 ± 10%; p = 0.22). Participants' knowledge improved with boot camp training (PRE 47 ± 11% vs. POST 70 ± 8%; p < 0.001) and there was excellent moderate-term retention of the information taught at boot camp (PRE 47 ± 11% vs. F/U 71 ± 8%; p < 0.001). Testing done at the beginning of fellowship demonstrated significantly better scores in participants versus controls (F/U 71 ± 8% vs. CTRL 52 ± 10%; p < 0.001). Boot camp participants demonstrated a significant improvement in basic cardiology knowledge after the training program and had excellent moderate-term retention of that knowledge. Participants began fellowship with a larger fund of knowledge than those fellows who did not attend.

  15. African Retentions in Blues and Jazz.

    ERIC Educational Resources Information Center

    Meadows, Eddie S.

    1979-01-01

    The perseverance of African musical characteristics among American Blacks is an historic reality. African retentions have been recorded in Black music of the antebellum period. Various African scales and rhythms permeate Black American music today as evidenced in the retentions found in blues and jazz. (RLV)

  16. Clinical trial management of participant recruitment, enrollment, engagement, and retention in the SMART study using a Marketing and Information Technology (MARKIT) model

    PubMed Central

    Gupta, Anjali; Calfas, Karen J.; Marshall, Simon J.; Robinson, Thomas N.; Rock, Cheryl L.; Huang, Jeannie S.; Epstein-Corbin, Melanie; Servetas, Christina; Donohue, Michael C.; Norman, Gregory J.; Raab, Fredric; Merchant, Gina; Fowler, James H.; Griswold, William G.; Fogg, B.J.; Patrick, Kevin

    2015-01-01

    Advances in information technology and near ubiquity of the Internet have spawned novel modes of communication and unprecedented insights into human behavior via the digital footprint. Health behavior randomized controlled trials (RCTs), especially technology-based, can leverage these advances to improve the overall clinical trials management process and benefit from improvements at every stage, from recruitment and enrollment to engagement and retention. In this paper, we report the results for recruitment and retention of participants in the SMART study and introduce a new model for clinical trials management that is a result of interdisciplinary team science. The MARKIT model brings together best practices from information technology, marketing, and clinical research into a single framework to maximize efforts for recruitment, enrollment, engagement, and retention of participants into a RCT. These practices may have contributed to the study’s on-time recruitment that was within budget, 86% retention at 24 months, and a minimum of 57% engagement with the intervention over the 2-year RCT. Use of technology in combination with marketing practices may enable investigators to reach a larger and more diverse community of participants to take part in technology-based clinical trials, help maximize limited resources, and lead to more cost-effective and efficient clinical trial management of study participants as modes of communication evolve among the target population of participants. PMID:25866383

  17. Black Student Retention in Higher Education.

    ERIC Educational Resources Information Center

    Lang, Marvel, Ed.; Ford, Clinita A., Ed.

    This collection focuses on problems in the recruitment, enrollment and retention of Blacks in higher education in America. The following chapters are provided: "The Black Student Retention Problem in Higher Education: Some Introductory Perspectives" (Marvel Lang); "Early Acceptance and Institutional Linkages in a Model Program of Recruitment,…

  18. Retention and Advancement in the Retail Industry: A Career Ladder Approach.

    ERIC Educational Resources Information Center

    Prince, Heath J.

    Retailing is the largest industry in the United States, employing roughly 18 percent of the total labor force. However, high turnover resulting from low wages in entry-level positions and the perceptions of retail workers that job security is far from certain and that advancement potential is limited have resulted in low levels of employee…

  19. Tumor Blood Vessel Dynamics

    NASA Astrophysics Data System (ADS)

    Munn, Lance

    2009-11-01

    ``Normalization'' of tumor blood vessels has shown promise to improve the efficacy of chemotherapeutics. In theory, anti-angiogenic drugs targeting endothelial VEGF signaling can improve vessel network structure and function, enhancing the transport of subsequent cytotoxic drugs to cancer cells. In practice, the effects are unpredictable, with varying levels of success. The predominant effects of anti-VEGF therapies are decreased vessel leakiness (hydraulic conductivity), decreased vessel diameters and pruning of the immature vessel network. It is thought that each of these can influence perfusion of the vessel network, inducing flow in regions that were previously sluggish or stagnant. Unfortunately, when anti-VEGF therapies affect vessel structure and function, the changes are dynamic and overlapping in time, and it has been difficult to identify a consistent and predictable normalization ``window'' during which perfusion and subsequent drug delivery is optimal. This is largely due to the non-linearity in the system, and the inability to distinguish the effects of decreased vessel leakiness from those due to network structural changes in clinical trials or animal studies. We have developed a mathematical model to calculate blood flow in complex tumor networks imaged by two-photon microscopy. The model incorporates the necessary and sufficient components for addressing the problem of normalization of tumor vasculature: i) lattice-Boltzmann calculations of the full flow field within the vasculature and within the tissue, ii) diffusion and convection of soluble species such as oxygen or drugs within vessels and the tissue domain, iii) distinct and spatially-resolved vessel hydraulic conductivities and permeabilities for each species, iv) erythrocyte particles advecting in the flow and delivering oxygen with real oxygen release kinetics, v) shear stress-mediated vascular remodeling. This model, guided by multi-parameter intravital imaging of tumor vessel structure

  20. An automated method for accurate vessel segmentation

    NASA Astrophysics Data System (ADS)

    Yang, Xin; Liu, Chaoyue; Le Minh, Hung; Wang, Zhiwei; Chien, Aichi; (Tim Cheng, Kwang-Ting

    2017-05-01

    Vessel segmentation is a critical task for various medical applications, such as diagnosis assistance of diabetic retinopathy, quantification of cerebral aneurysm’s growth, and guiding surgery in neurosurgical procedures. Despite technology advances in image segmentation, existing methods still suffer from low accuracy for vessel segmentation in the two challenging while common scenarios in clinical usage: (1) regions with a low signal-to-noise-ratio (SNR), and (2) at vessel boundaries disturbed by adjacent non-vessel pixels. In this paper, we present an automated system which can achieve highly accurate vessel segmentation for both 2D and 3D images even under these challenging scenarios. Three key contributions achieved by our system are: (1) a progressive contrast enhancement method to adaptively enhance contrast of challenging pixels that were otherwise indistinguishable, (2) a boundary refinement method to effectively improve segmentation accuracy at vessel borders based on Canny edge detection, and (3) a content-aware region-of-interests (ROI) adjustment method to automatically determine the locations and sizes of ROIs which contain ambiguous pixels and demand further verification. Extensive evaluation of our method is conducted on both 2D and 3D datasets. On a public 2D retinal dataset (named DRIVE (Staal 2004 IEEE Trans. Med. Imaging 23 501-9)) and our 2D clinical cerebral dataset, our approach achieves superior performance to the state-of-the-art methods including a vesselness based method (Frangi 1998 Int. Conf. on Medical Image Computing and Computer-Assisted Intervention) and an optimally oriented flux (OOF) based method (Law and Chung 2008 European Conf. on Computer Vision). An evaluation on 11 clinical 3D CTA cerebral datasets shows that our method can achieve 94% average accuracy with respect to the manual segmentation reference, which is 23% to 33% better than the five baseline methods (Yushkevich 2006 Neuroimage 31 1116-28; Law and Chung 2008

  1. Effect of hydraulic retention time on inorganic nutrient recovery and biodegradable organics removal in a biofilm reactor treating plant biomass leachate

    NASA Technical Reports Server (NTRS)

    Krumins, Valdis; Hummerick, Mary; Levine, Lanfang; Strayer, Richard; Adams, Jennifer L.; Bauer, Jan

    2002-01-01

    A fixed-film (biofilm) reactor was designed and its performance was determined at various retention times. The goal was to find the optimal retention time for recycling plant nutrients in an advanced life support system, to minimize the size, mass, and volume (hold-up) of a production model. The prototype reactor was tested with aqueous leachate from wheat crop residue at 24, 12, 6, and 3 h hydraulic retention times (HRTs). Biochemical oxygen demand (BOD), nitrates and other plant nutrients, carbohydrates, total phenolics, and microbial counts were monitored to characterize reactor performance. BOD removal decreased significantly from 92% at the 24 h HRT to 73% at 3 h. Removal of phenolics was 62% at the 24 h retention time, but 37% at 3 h. Dissolved oxygen concentrations, nitric acid consumption, and calcium and magnesium removals were also affected by HRT. Carbohydrate removals, carbon dioxide (CO2) productions, denitrification, potassium concentrations, and microbial counts were not affected by different retention times. A 6 h HRT will be used in future studies to determine the suitability of the bioreactor effluent for hydroponic plant production.

  2. Advanced imaging in acute stroke management-Part I: Computed tomographic.

    PubMed

    Saini, Monica; Butcher, Ken

    2009-01-01

    Neuroimaging is fundamental to stroke diagnosis and management. Non-contrast computed tomography (NCCT) has been the primary imaging modality utilized for this purpose for almost four decades. Although NCCT does permit identification of intracranial hemorrhage and parenchymal ischemic changes, insights into blood vessel patency and cerebral perfusion are limited. Advances in reperfusion strategies have made identification of potentially salvageable brain tissue a more practical concern. Advances in CT technology now permit identification of acute and chronic arterial lesions, as well as cerebral blood flow deficits. This review outlines principles of advanced CT image acquisition and its utility in acute stroke management.

  3. Determinants of injuries in passenger vessel accidents.

    PubMed

    Yip, Tsz Leung; Jin, Di; Talley, Wayne K

    2015-09-01

    This paper investigates determinants of crew and passenger injuries in passenger vessel accidents. Crew and passenger injury equations are estimated for ferry, ocean cruise, and river cruise vessel accidents, utilizing detailed data of individual vessel accidents that were investigated by the U.S. Coast Guard during the time period 2001-2008. The estimation results provide empirical evidence (for the first time in the literature) that crew injuries are determinants of passenger injuries in passenger vessel accidents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Fall 1982 Retention Study.

    ERIC Educational Resources Information Center

    Peralta Community Coll. District, Oakland, CA. Office of Research, Planning and Development.

    In fall 1982, a study was conducted in the Peralta Community College District (PCCD) using withdrawal and grade distribution data to analyze student retention patterns. Successful retention rates were based on the percentage of students who received a passing grade, while total retention rates were based on the percentage of students who received…

  5. Debulking Surgery for Elephantiasis Nostras With Large Ectatic Podoplanin-Negative Lymphatic Vessels in Patients With Lipo-Lymphedema

    PubMed Central

    Wollina, Uwe; Heinig, Birgit; Schönlebe, Jaqueline; Nowak, Andreas

    2014-01-01

    Objective: Elephantiasis nostras is a rare complication in advanced lipo-lymphedema. While lipedema can be treated by liposuction and lymphedema by decongestive lymphatic therapy, elephantiasis nostras may need debulking surgery. Methods: We present 2 cases of advanced lipo-lymphedema complicated by elephantiasis nostras. After tumescent microcannular laser-assisted liposuction both patients underwent a debulking surgery with a modification of Auchincloss-Kim's technique. Histologic examination of the tissue specimen was performed. Results: The surgical treatment was well tolerated and primary healing was uneventful. After primary wound healing and ambulation of the patients, a delayed ulceration with lymphorrhea developed. It was treated by surgical necrectomy and vacuum-assisted closure leading to complete healing. Mobility of the leg was much improved. Histologic examination revealed massive ectatic lymphatic vessels nonreactive for podoplanin. Conclusions: Debulking surgery can be an adjuvant technique for elephantiasis nostras in advanced lipo-lymphedema. Although delayed postoperative wound healing problems were observed, necrectomy and vacuum-assisted closure achieved a complete healing. Histologic data suggest that the ectatic lymphatic vessels in these patients resemble finding in podoplanin knockout mice. The findings would explain the limitations of decongestive lymphatic therapy and tumescent liposuction in such patients and their predisposition to relapsing erysipelas. PMID:24741382

  6. Deuterium retention in tungsten in dependence of the surface conditions

    NASA Astrophysics Data System (ADS)

    Ogorodnikova, O. V.; Roth, J.; Mayer, M.

    2003-03-01

    The paper reviews hydrogen isotope retention and migration in tungsten (W). Due to a large scatter of the deuterium (D) retention database, new measurements of ion-driven D retention in polycrystalline W foil have been performed to clarify the mechanism of hydrogen isotope inventory in W. Deuterium retention has been investigated as a function of ion fluence, implantation temperature, incident energy and surface conditions. Special attention has been given on the investigation of D retention in thin films of tungsten carbide and tungsten oxide which can be formed on W surface in a fusion device. Such kinds of films increase the D retention in W. Several points are reviewed: (i) inventory in pure W, (ii) inventory in W pre-implanted by carbon ions and (iii) inventory in tungsten oxide.

  7. 33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Sailing vessels underway and... OF HOMELAND SECURITY INLAND NAVIGATION RULES RULES Lights and Shapes § 83.25 Sailing vessels underway and vessels under oars (Rule 25). (a) Sailing vessels underway. A sailing vessel underway shall...

  8. 33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Sailing vessels underway and... OF HOMELAND SECURITY INLAND NAVIGATION RULES RULES Lights and Shapes § 83.25 Sailing vessels underway and vessels under oars (Rule 25). (a) Sailing vessels underway. A sailing vessel underway shall...

  9. Liposome retention in size exclusion chromatography

    PubMed Central

    Ruysschaert, Tristan; Marque, Audrey; Duteyrat, Jean-Luc; Lesieur, Sylviane; Winterhalter, Mathias; Fournier, Didier

    2005-01-01

    Background Size exclusion chromatography is the method of choice for separating free from liposome-encapsulated molecules. However, if the column is not presaturated with lipids this type of chromatography causes a significant loss of lipid material. To date, the mechanism of lipid retention is poorly understood. It has been speculated that lipid binds to the column material or the entire liposome is entrapped inside the void. Results Here we show that intact liposomes and their contents are retained in the exclusion gel. Retention depends on the pore size, the smaller the pores, the higher the retention. Retained liposomes are not tightly fixed to the beads and are slowly released from the gels upon direct or inverted eluent flow, long washing steps or column repacking. Further addition of free liposomes leads to the elution of part of the gel-trapped liposomes, showing that the retention is transitory. Trapping reversibility should be related to a mechanism of partitioning of the liposomes between the stationary phase, water-swelled polymeric gel, and the mobile aqueous phase. Conclusion Retention of liposomes by size exclusion gels is a dynamic and reversible process, which should be accounted for to control lipid loss and sample contamination during chromatography. PMID:15885140

  10. On the relation between motivation and retention in educational contexts: The role of intentional and unintentional mind wandering.

    PubMed

    Seli, Paul; Wammes, Jeffrey D; Risko, Evan F; Smilek, Daniel

    2016-08-01

    Highly motivated students often exhibit better academic performance than less motivated students. However, to date, the specific cognitive mechanisms through which motivation increases academic achievement are not well understood. Here we explored the possibility that mind wandering mediates the relation between motivation and academic performance, and additionally, we examined possible mediation by both intentional and unintentional forms of mind wandering. We found that participants reporting higher motivation to learn in a lecture-based setting tended to engage in less mind wandering, and that this decrease in mind wandering was in turn associated with greater retention of the lecture material. Critically, we also found that the influence of motivation on retention was mediated by both intentional and unintentional types of mind wandering. Not only do the present results advance our theoretical understanding of the mechanisms underlying the relation between motivation and academic achievement, they also provide insights into possible methods of intervention that may be useful in improving student retention in educational settings.

  11. Recruitment and retention strategies for expert nurses in abortion care provision.

    PubMed

    McLemore, Monica R; Levi, Amy; James, E Angel

    2015-06-01

    The purpose of this thematic analysis is to describe recruitment, retention and career development strategies for expert nurses in abortion care provision. Thematic analysis influenced by grounded theory methods were used to analyze interviews, which examined cognitive, emotional, and behavioral processes associated with how nurses make decisions about participation in abortion care provision. The purposive sample consisted of 16 nurses, who were interviewed between November 2012 and August 2013, who work (or have worked) with women seeking abortions in abortion clinics, emergency departments, labor and delivery units and post anesthesia care units. Several themes emerged from the broad categories that contribute to successful nurse recruitment, retention, and career development in abortion care provision. All areas were significantly influenced by engagement in leadership activities and professional society membership. The most notable theme specific to recruitment was exposure to abortion through education as a student, or through an employer. Retention is most influenced by flexibility in practice, including: advocating for patients, translating one's skill set, believing that nursing is shared work, and juggling multiple roles. Lastly, providing on the job training opportunities for knowledge and skill advancement best enables career development. Clear mechanisms exist to develop expert nurses in abortion care provision. The findings from our study should encourage employers to provide exposure opportunities, develop activities to recruit and retain nurses, and to support career development in abortion care provision. Additionally, future workforce development efforts should include and engage nursing education institutions and employers to design structured support for this trajectory. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Blood Vessels in Allotransplantation.

    PubMed

    Abrahimi, P; Liu, R; Pober, J S

    2015-07-01

    Human vascularized allografts are perfused through blood vessels composed of cells (endothelium, pericytes, and smooth muscle cells) that remain largely of graft origin and are thus subject to host alloimmune responses. Graft vessels must be healthy to maintain homeostatic functions including control of perfusion, maintenance of permselectivity, prevention of thrombosis, and participation in immune surveillance. Vascular cell injury can cause dysfunction that interferes with these processes. Graft vascular cells can be activated by mediators of innate and adaptive immunity to participate in graft inflammation contributing to both ischemia/reperfusion injury and allograft rejection. Different forms of rejection may affect graft vessels in different ways, ranging from thrombosis and neutrophilic inflammation in hyperacute rejection, to endothelialitis/intimal arteritis and fibrinoid necrosis in acute cell-mediated or antibody-mediated rejection, respectively, and to diffuse luminal stenosis in chronic rejection. While some current therapies targeting the host immune system do affect graft vascular cells, direct targeting of the graft vasculature may create new opportunities for preventing allograft injury and loss. © Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.

  13. Distribution and permeability of capillaries at the skin of the conception vessel and the governor vessel in healthy rabbits.

    PubMed

    Zhou, Dan; Guo, Yi; Guo, Yong-Ming; Zhang, Sai; Pan, Ping

    2011-12-01

    To investigate the distribution and permeability of blood vessels on the Conception Vessel and the Governor Vessel in the physiological state. Evans blue (EB) solution was injected into the marginal ear vein of healthy rabbits. Three hours after injection, the rabbits were sacrificed and the skin on the Conception Vessel and the Governor Vessel and the corresponding bilateral non-channels was collected. EB was extracted with 7:3 acetone: physiological saline, and the absorbance of EB at each skin tissue was measured with a spectrophotometer. The A value of EB absorbance at the Conception Vessel on the abdominal skin was lower than that of the corresponding bilateral non-channels with a statistically significant difference (P< 0.01). The A value of EB absorbance at the Governor Vessel on the back was higher than that of the corresponding bilateral non-channels (P < 0.05). There was no statistical difference in the A value of EB absorbance between the bilateral non-channels of the abdomen and the back (P > 0.05). There were differences in capillary distribution and permeability between the Conception Vessel, the Governor Vessel and the corresponding bilateral non-meridians.

  14. Scientific method by argumentation design: learning process for maintaining student’s retention

    NASA Astrophysics Data System (ADS)

    Siswanto; Yusiran; Asriyadin; Gumilar, S.; Subali, B.

    2018-03-01

    The purpose of this research describes the effect of scientific methods designed by argumentation in maintaining retention of pre-service physics teachers (students) in mechanical concept. This learning consists of five stages including the first two stages namely observing and questioning. While the next three stages of reasoning, trying, and communicating are made of argumentation design. To know the effectiveness of treatment, students are given pre-test and post-test in one time. On the other hand, students were given advanced post-test to know the durability of retention as many as four times in four months. The results show that there was mean difference between pre-test and post-test based on the Wilcoxon test (z = -3.4, p=0.001). While the effectiveness of treatment is in the high category based on normalized gain values ( = 0.86). Meanwhile, mean difference of all post-test is significantly different based on Analysis of Varian (F = 365.63, p = 0.00). However, in the fourth month, students retention rates began to stabilize based on Tuckey’s HSD (p=0.074) for comparison of mean difference between fourth and fifth post-test. Overall, learning designed can maintain students retention within 4 months after the learning finish.

  15. AdVance male sling

    PubMed Central

    Chung, Amanda S. J.; Suarez, Oscar A.

    2017-01-01

    The AdVance sling (American Medical Systems, Minnetonka, MN, United States of America) is a synthetic transobturator sling, which is a safe and effective minimally invasive treatment for mild to moderate stress urinary incontinence (SUI) in male patients. This article provides a step-by-step description of our technique for placement of the AdVance male sling, including details and nuances gained from surgical experience, advice for avoidance of complications and discussion on management of complications and sling failures. Patient selection is very important, including exclusion and preoperative treatment of urethral stenosis and bladder dysfunction. Previous pelvic radiation is a poor prognostic factor. In brief, the steps of sling placement are: (I) mobilization of the corpus spongiosum (CS); (II) marking and mobilization of the central tendon; (III) passage of the helical trocar needles exiting at the apex of the angle between the CS and inferior pubic ramus; (IV) fixation of the broad part of the sling body to the CS at the previous mark; (V) cystoscopy during sling tensioning; (VI) placement of a Foley urethral catheter; (VII) Subcutaneous tunnelling of the sling arms back toward the midline; (VIII) wound closure. The most common early postoperative complication is urinary retention but long-term retention is extremely rare. Management of sling failures include placement of an artificial urinary sphincter, repeat AdVance sling, urethral bulking agent or ProACT device. PMID:28904900

  16. Recruitment, Promotion and Retention of Women in Academic Medicine: How Institutions Are Addressing Gender Disparities

    PubMed Central

    Carr, Phyllis L.; Gunn, Christine; Raj, Anita; Kaplan, Samantha; Freund, Karen M.

    2017-01-01

    Objective Greater numbers of women in medicine have not resulted in more women achieving senior positions. Programs supporting recruitment, promotion and retention of women in academic medicine could help to achieve greater advancement of more women to leadership positions. Qualitative research was conducted to understand such programs at 23 institutions and, using the social ecological model, examine how they operate at the individual, interpersonal, institutional, academic community and policy levels. Methods Telephone interviews were conducted with faculty representatives (N=44) of the Group on Women in Medicine and Science (GWIMS), Diversity and Inclusion (GDI) or senior leaders with knowledge on gender climate in 24 medical schools. Four trained interviewers conducted semi-structured interviews that addressed faculty perceptions of gender equity and advancement, which were audio-taped and transcribed. The data were categorized into three content areas: recruitment, promotion and retention, and coded a priori for each area based on their social ecological level of operation. Findings Participants from nearly 40% of the institutions reported no special programs for recruiting, promoting or retaining women, largely describing such programming as unnecessary. Existing programs primarily targeted the individual and interpersonal levels simultaneously, via training, mentoring, and networking, or the institutional level, via search committee trainings, child and elder care, and spousal hiring programs. Lesser effort at the academic community and policy levels were described. Conclusions Our findings demonstrate that many US medical schools have no programs supporting gender equity among medical faculty. Existing programs primarily target the individual or interpersonal level of the social ecological interaction. The academic community and broader policy environment require greater focus as levels with little attention to advancing women’s careers. Universal multi

  17. Recruitment, Promotion, and Retention of Women in Academic Medicine: How Institutions Are Addressing Gender Disparities.

    PubMed

    Carr, Phyllis L; Gunn, Christine; Raj, Anita; Kaplan, Samantha; Freund, Karen M

    Greater numbers of women in medicine have not resulted in more women achieving senior positions. Programs supporting the recruitment, promotion, and retention of women in academic medicine could help to achieve greater advancement of more women to leadership positions. Qualitative research was conducted to understand such programs at 23 institutions and, using the social ecological model, examine how they operate at the individual, interpersonal, institutional, academic community, and policy levels. Telephone interviews were conducted with faculty representatives (n = 44) of the Group on Women in Medicine and Science, Diversity and Inclusion, or senior leaders with knowledge on gender climate in 24 medical schools. Four trained interviewers conducted semistructured interviews that addressed faculty perceptions of gender equity and advancement, which were audiotaped and transcribed. The data were categorized into three content areas-recruitment, promotion, and retention-and coded a priori for each area based on their social ecological level of operation. Participants from nearly 40% of the institutions reported no special programs for recruiting, promoting, or retaining women, largely describing such programming as unnecessary. Existing programs primarily targeted the individual and interpersonal levels simultaneously, via training, mentoring, and networking, or the institutional level, via search committee trainings, child and elder care, and spousal hiring programs. Lesser effort at the academic community and policy levels were described. Our findings demonstrate that many U.S. medical schools have no programs supporting gender equity among medical faculty. Existing programs primarily target the individual or interpersonal level of the social ecological interaction. The academic community and broader policy environment require greater focus as levels with little attention to advancing women's careers. Universal multilevel efforts are needed to more effectively

  18. Practical solutions for staff recruitment & retention.

    PubMed

    Vander Hoek, N

    2001-01-01

    There are three essential topics for radiology managers to consider in light of persistent staffing shortages: support of the profession and educational programs, perks as recruitment tools and incentives as retention tools. Some activities that can help support departments and educational programs for radiologic technologists are job shadowing, training for volunteer services, advanced placement for school applicants, sponsoring an educational program or clinical training site, creating a positive work environment and supporting outreach projects geared to local high schools. Traditional perks used in recruitment efforts have included relocation assistance, travel and lodging expenses during the interview process, loan repayment, scholarships and sign-on bonuses. Some common incentives for retaining employees are tuition reimbursement, cross training, availability of educational resources, continuing education opportunities, professional development and incremental increases in salary. There are many other tools that can be used, such as career ladders, creating an environment conducive to teamwork or a more personal atmosphere and showcasing talents of various staff members. There is much overlap among these suggestions in support of the profession and educational programs, recruitment and retention of qualified staff radiologic technologists. Radiology managers can and should be creative in developing different programs to build loyalty and commitment to a radiology department.

  19. Clinical trial management of participant recruitment, enrollment, engagement, and retention in the SMART study using a Marketing and Information Technology (MARKIT) model.

    PubMed

    Gupta, Anjali; Calfas, Karen J; Marshall, Simon J; Robinson, Thomas N; Rock, Cheryl L; Huang, Jeannie S; Epstein-Corbin, Melanie; Servetas, Christina; Donohue, Michael C; Norman, Gregory J; Raab, Fredric; Merchant, Gina; Fowler, James H; Griswold, William G; Fogg, B J; Patrick, Kevin

    2015-05-01

    Advances in information technology and near ubiquity of the Internet have spawned novel modes of communication and unprecedented insights into human behavior via the digital footprint. Health behavior randomized controlled trials (RCTs), especially technology-based, can leverage these advances to improve the overall clinical trials management process and benefit from improvements at every stage, from recruitment and enrollment to engagement and retention. In this paper, we report the results for recruitment and retention of participants in the SMART study and introduce a new model for clinical trials management that is a result of interdisciplinary team science. The MARKIT model brings together best practices from information technology, marketing, and clinical research into a single framework to maximize efforts for recruitment, enrollment, engagement, and retention of participants into a RCT. These practices may have contributed to the study's on-time recruitment that was within budget, 86% retention at 24 months, and a minimum of 57% engagement with the intervention over the 2-year RCT. Use of technology in combination with marketing practices may enable investigators to reach a larger and more diverse community of participants to take part in technology-based clinical trials, help maximize limited resources, and lead to more cost-effective and efficient clinical trial management of study participants as modes of communication evolve among the target population of participants. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  20. Comparison of retention between maxillary milled and conventional denture bases: A clinical study.

    PubMed

    AlHelal, Abdulaziz; AlRumaih, Hamad S; Kattadiyil, Mathew T; Baba, Nadim Z; Goodacre, Charles J

    2017-02-01

    Clinical studies comparing the retention values of milled denture bases with those of conventionally processed denture bases are lacking. The purpose of this clinical study was to compare the retention values of conventional heat-polymerized denture bases with those of digitally milled maxillary denture bases. Twenty individuals with completely edentulous maxillary arches participated in this study. Definitive polyvinyl siloxane impressions were scanned (iSeries; Dental Wings), and the standard tessellation language files were sent to Global Dental Science for the fabrication of a computer-aided design and computer-aided manufacturing (CAD-CAM) milled denture base (group MB) (AvaDent). The impression was then poured to obtain a definitive cast that was used to fabricate a heat-polymerized acrylic resin denture base resin (group HB). A custom-designed testing device was used to measure denture retention (N). Each denture base was subjected to a vertical pulling force by using an advanced digital force gauge 3 times at 10-minute intervals. The average retention of the 2 fabrication methods was compared using repeated ANOVA (α=.05). Significantly increased retention was observed for the milled denture bases compared with that of the conventional heat-polymerized denture bases (P<.001). The retention offered by milled complete denture bases from prepolymerized poly(methyl methacrylate) resin was significantly higher than that offered by conventional heat- polymerized denture bases. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  1. Integrating Multiple Autonomous Underwater Vessels, Surface Vessels and Aircraft into Oceanographic Research Vessel Operations

    NASA Astrophysics Data System (ADS)

    McGillivary, P. A.; Borges de Sousa, J.; Martins, R.; Rajan, K.

    2012-12-01

    Autonomous platforms are increasingly used as components of Integrated Ocean Observing Systems and oceanographic research cruises. Systems deployed can include gliders or propeller-driven autonomous underwater vessels (AUVs), autonomous surface vessels (ASVs), and unmanned aircraft systems (UAS). Prior field campaigns have demonstrated successful communication, sensor data fusion and visualization for studies using gliders and AUVs. However, additional requirements exist for incorporating ASVs and UASs into ship operations. For these systems to be optimally integrated into research vessel data management and operational planning systems involves addressing three key issues: real-time field data availability, platform coordination, and data archiving for later analysis. A fleet of AUVs, ASVs and UAS deployed from a research vessel is best operated as a system integrated with the ship, provided communications among them can be sustained. For this purpose, Disruptive Tolerant Networking (DTN) software protocols for operation in communication-challenged environments help ensure reliable high-bandwidth communications. Additionally, system components need to have considerable onboard autonomy, namely adaptive sampling capabilities using their own onboard sensor data stream analysis. We discuss Oceanographic Decision Support System (ODSS) software currently used for situational awareness and planning onshore, and in the near future event detection and response will be coordinated among multiple vehicles. Results from recent field studies from oceanographic research vessels using AUVs, ASVs and UAS, including the Rapid Environmental Picture (REP-12) cruise, are presented describing methods and results for use of multi-vehicle communication and deliberative control networks, adaptive sampling with single and multiple platforms, issues relating to data management and archiving, and finally challenges that remain in addressing these technological issues. Significantly, the

  2. Assessing Chemical Retention Process Controls in Ponds

    NASA Astrophysics Data System (ADS)

    Torgersen, T.; Branco, B.; John, B.

    2002-05-01

    Small ponds are a ubiquitous component of the landscape and have earned a reputation as effective chemical retention devices. The most common characterization of pond chemical retention is the retention coefficient, Ri= ([Ci]inflow-[Ci] outflow)/[Ci]inflow. However, this parameter varies widely in one pond with time and among ponds. We have re-evaluated literature reported (Borden et al., 1998) monthly average retention coefficients for two ponds in North Carolina. Employing a simple first order model that includes water residence time, the first order process responsible for species removal have been separated from the water residence time over which it acts. Assuming the rate constant for species removal is constant within the pond (arguable at least), the annual average rate constant for species removal is generated. Using the annual mean rate constant for species removal and monthly water residence times results in a significantly enhanced predictive capability for Davis Pond during most months of the year. Predictive ability remains poor in Davis Pond during winter/unstratified periods when internal loading of P and N results in low to negative chemical retention. Predictive ability for Piedmont Pond (which has numerous negative chemical retention periods) is improved but not to the same extent as Davis Pond. In Davis Pond, the rate constant for sediment removal (each month) is faster than the rate constant for water and explains the good predictability for sediment retention. However, the removal rate constant for P and N is slower than the removal rate constant for sediment (longer water column residence time for P,N than for sediment). Thus sedimentation is not an overall control on nutrient retention. Additionally, the removal rate constant for P is slower than for TOC (TOC is not the dominate removal process for P) and N is removed slower than P (different in pond controls). For Piedmont Pond, sediment removal rate constants are slower than the removal

  3. A hybrid lung and vessel segmentation algorithm for computer aided detection of pulmonary embolism

    NASA Astrophysics Data System (ADS)

    Raghupathi, Laks; Lakare, Sarang

    2009-02-01

    Advances in multi-detector technology have made CT pulmonary angiography (CTPA) a popular radiological tool for pulmonary emboli (PE) detection. CTPA provide rich detail of lung anatomy and is a useful diagnostic aid in highlighting even very small PE. However analyzing hundreds of slices is laborious and time-consuming for the practicing radiologist which may also cause misdiagnosis due to the presence of various PE look-alike. Computer-aided diagnosis (CAD) can be a potential second reader in providing key diagnostic information. Since PE occurs only in vessel arteries, it is important to mark this region of interest (ROI) during CAD preprocessing. In this paper, we present a new lung and vessel segmentation algorithm for extracting contrast-enhanced vessel ROI in CTPA. Existing approaches to segmentation either provide only the larger lung area without highlighting the vessels or is computationally prohibitive. In this paper, we propose a hybrid lung and vessel segmentation which uses an initial lung ROI and determines the vessels through a series of refinement steps. We first identify a coarse vessel ROI by finding the "holes" from the lung ROI. We then use the initial ROI as seed-points for a region-growing process while carefully excluding regions which are not relevant. The vessel segmentation mask covers 99% of the 259 PE from a real-world set of 107 CTPA. Further, our algorithm increases the net sensitivity of a prototype CAD system by 5-9% across all PE categories in the training and validation data sets. The average run-time of algorithm was only 100 seconds on a standard workstation.

  4. 46 CFR 61.10-5 - Pressure vessels in service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... pressure vessels used in refrigeration service. (2) If your vessel's Certificate of Inspection is renewed...: all tubular heat exchangers, hydraulic accumulators, and all pressure vessels used in refrigeration... refrigeration service. (3) Hydraulic accumulators. (4) Pressure vessels which have been satisfactorily examined...

  5. Blood vessel rupture by cavitation

    PubMed Central

    Chen, Hong; Brayman, Andrew A.; Bailey, Michael R.

    2011-01-01

    Cavitation is thought to be one mechanism for vessel rupture during shock wave lithotripsy treatment. However, just how cavitation induces vessel rupture remains unknown. In this work, a high-speed photomicrography system was set up to directly observe the dynamics of bubbles inside blood vessels in ex vivo rat mesenteries. Vascular rupture correlating to observed bubble dynamics were examined by imaging bubble extravasation and dye leakage. The high-speed images show that bubble expansion can cause vessel distention, and bubble collapse can lead to vessel invagination. Liquid jets were also observed to form. Our results suggest that all three mechanisms, vessel distention, invagination and liquid jets, can contribute to vessel rupture. PMID:20680255

  6. Retention Projection” Enables Reliable Use of Shared Gas Chromatographic Retention Data Across Labs, Instruments, and Methods

    PubMed Central

    Barnes, Brian B.; Wilson, Michael B.; Carr, Peter W.; Vitha, Mark F.; Broeckling, Corey D.; Heuberger, Adam L.; Prenni, Jessica; Janis, Gregory C.; Corcoran, Henry; Snow, Nicholas H.; Chopra, Shilpi; Dhandapani, Ramkumar; Tawfall, Amanda; Sumner, Lloyd W.; Boswell, Paul G.

    2014-01-01

    Gas chromatography-mass spectrometry (GC-MS) is a primary tool used to identify compounds in complex samples. Both mass spectra and GC retention times are matched to those of standards, but it is often impractical to have standards on hand for every compound of interest, so we must rely on shared databases of MS data and GC retention information. Unfortunately, retention databases (e.g. linear retention index libraries) are experimentally restrictive, notoriously unreliable, and strongly instrument dependent, relegating GC retention information to a minor, often negligible role in compound identification despite its potential power. A new methodology called “retention projection” has great potential to overcome the limitations of shared chromatographic databases. In this work, we tested the reliability of the methodology in five independent laboratories. We found that even when each lab ran nominally the same method, the methodology was 3-fold more accurate than retention indexing because it properly accounted for unintentional differences between the GC-MS systems. When the labs used different methods of their own choosing, retention projections were 4- to 165-fold more accurate. More importantly, the distribution of error in the retention projections was predictable across different methods and labs, thus enabling automatic calculation of retention time tolerance windows. Tolerance windows at 99% confidence were generally narrower than those widely used even when physical standards are on hand to measure their retention. With its high accuracy and reliability, the new retention projection methodology makes GC retention a reliable, precise tool for compound identification, even when standards are not available to the user. PMID:24205931

  7. A computational algorithm addressing how vessel length might depend on vessel diameter

    Treesearch

    Jing Cai; Shuoxin Zhang; Melvin T. Tyree

    2010-01-01

    The objective of this method paper was to examine a computational algorithm that may reveal how vessel length might depend on vessel diameter within any given stem or species. The computational method requires the assumption that vessels remain approximately constant in diameter over their entire length. When this method is applied to three species or hybrids in the...

  8. LANL Robotic Vessel Scanning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Webber, Nels W.

    Los Alamos National Laboratory in J-1 DARHT Operations Group uses 6ft spherical vessels to contain hazardous materials produced in a hydrodynamic experiment. These contaminated vessels must be analyzed by means of a worker entering the vessel to locate, measure, and document every penetration mark on the vessel. If the worker can be replaced by a highly automated robotic system with a high precision scanner, it will eliminate the risks to the worker and provide management with an accurate 3D model of the vessel presenting the existing damage with the flexibility to manipulate the model for better and more in-depth assessment.Themore » project was successful in meeting the primary goal of installing an automated system which scanned a 6ft vessel with an elapsed time of 45 minutes. This robotic system reduces the total time for the original scope of work by 75 minutes and results in excellent data accumulation and transmission to the 3D model imaging program.« less

  9. 33 CFR 90.3 - Pushing vessel and vessel being pushed: Composite unit.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... pushed: Composite unit. 90.3 Section 90.3 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... vessel being pushed: Composite unit. Rule 24(b) of the Inland Rules states that when a pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit, they are regarded as a power...

  10. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...

  11. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...

  12. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...

  13. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...

  14. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... boats. 116.1120 Section 116.1120 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SMALL... Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck vessels, and open boats must meet the applicable requirements of §§ 178.420, 178.430, 178.440, 178.450 in...

  15. Pressure vessel bottle mount

    NASA Technical Reports Server (NTRS)

    Wingett, Paul (Inventor)

    2001-01-01

    A mounting assembly for mounting a composite pressure vessel to a vehicle includes a saddle having a curved surface extending between two pillars for receiving the vessel. The saddle also has flanged portions which can be bolted to the vehicle. Each of the pillars has hole in which is mounted the shaft portion of an attachment member. A resilient member is disposed between each of the shaft portions and the holes and loaded by a tightening nut. External to the holes, each of the attachment members has a head portion to which a steel band is attached. The steel band circumscribes the vessel and translates the load on the springs into a clamping force on the vessel. As the vessel expands and contracts, the resilient members expand and contract so that the clamping force applied by the band to the vessel remains constant.

  16. 33 CFR 82.3 - Pushing vessel and vessel being pushed: Composite unit.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... pushed: Composite unit. 82.3 Section 82.3 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... vessel being pushed: Composite unit. Rule 24(b) of the 72 COLREGS states that when a pushing vessel and a vessel being pushed ahead are rigidly connected in a composite unit, they are regarded as a power-driven...

  17. Human Vision-Motivated Algorithm Allows Consistent Retinal Vessel Classification Based on Local Color Contrast for Advancing General Diagnostic Exams.

    PubMed

    Ivanov, Iliya V; Leitritz, Martin A; Norrenberg, Lars A; Völker, Michael; Dynowski, Marek; Ueffing, Marius; Dietter, Johannes

    2016-02-01

    Abnormalities of blood vessel anatomy, morphology, and ratio can serve as important diagnostic markers for retinal diseases such as AMD or diabetic retinopathy. Large cohort studies demand automated and quantitative image analysis of vascular abnormalities. Therefore, we developed an analytical software tool to enable automated standardized classification of blood vessels supporting clinical reading. A dataset of 61 images was collected from a total of 33 women and 8 men with a median age of 38 years. The pupils were not dilated, and images were taken after dark adaption. In contrast to current methods in which classification is based on vessel profile intensity averages, and similar to human vision, local color contrast was chosen as a discriminator to allow artery vein discrimination and arterial-venous ratio (AVR) calculation without vessel tracking. With 83% ± 1 standard error of the mean for our dataset, we achieved best classification for weighted lightness information from a combination of the red, green, and blue channels. Tested on an independent dataset, our method reached 89% correct classification, which, when benchmarked against conventional ophthalmologic classification, shows significantly improved classification scores. Our study demonstrates that vessel classification based on local color contrast can cope with inter- or intraimage lightness variability and allows consistent AVR calculation. We offer an open-source implementation of this method upon request, which can be integrated into existing tool sets and applied to general diagnostic exams.

  18. Radiant vessel auxiliary cooling system

    DOEpatents

    Germer, John H.

    1987-01-01

    In a modular liquid-metal pool breeder reactor, a radiant vessel auxiliary cooling system is disclosed for removing the residual heat resulting from the shutdown of a reactor by a completely passive heat transfer system. A shell surrounds the reactor and containment vessel, separated from the containment vessel by an air passage. Natural circulation of air is provided by air vents at the lower and upper ends of the shell. Longitudinal, radial and inwardly extending fins extend from the shell into the air passage. The fins are heated by radiation from the containment vessel and convect the heat to the circulating air. Residual heat from the primary reactor vessel is transmitted from the reactor vessel through an inert gas plenum to a guard or containment vessel designed to contain any leaking coolant. The containment vessel is conventional and is surrounded by the shell.

  19. Dissolver vessel bottom assembly

    DOEpatents

    Kilian, Douglas C.

    1976-01-01

    An improved bottom assembly is provided for a nuclear reactor fuel reprocessing dissolver vessel wherein fuel elements are dissolved as the initial step in recovering fissile material from spent fuel rods. A shock-absorbing crash plate with a convex upper surface is disposed at the bottom of the dissolver vessel so as to provide an annular space between the crash plate and the dissolver vessel wall. A sparging ring is disposed within the annular space to enable a fluid discharged from the sparging ring to agitate the solids which deposit on the bottom of the dissolver vessel and accumulate in the annular space. An inlet tangential to the annular space permits a fluid pumped into the annular space through the inlet to flush these solids from the dissolver vessel through tangential outlets oppositely facing the inlet. The sparging ring is protected against damage from the impact of fuel elements being charged to the dissolver vessel by making the crash plate of such a diameter that the width of the annular space between the crash plate and the vessel wall is less than the diameter of the fuel elements.

  20. No evidence for an open vessel effect in centrifuge-based vulnerability curves of a long-vesselled liana (Vitis vinifera).

    PubMed

    Jacobsen, Anna L; Pratt, R Brandon

    2012-06-01

    Vulnerability to cavitation curves are used to estimate xylem cavitation resistance and can be constructed using multiple techniques. It was recently suggested that a technique that relies on centrifugal force to generate negative xylem pressures may be susceptible to an open vessel artifact in long-vesselled species. Here, we used custom centrifuge rotors to measure different sample lengths of 1-yr-old stems of grapevine to examine the influence of open vessels on vulnerability curves, thus testing the hypothesized open vessel artifact. These curves were compared with a dehydration-based vulnerability curve. Although samples differed significantly in the number of open vessels, there was no difference in the vulnerability to cavitation measured on 0.14- and 0.271-m-long samples of Vitis vinifera. Dehydration and centrifuge-based curves showed a similar pattern of declining xylem-specific hydraulic conductivity (K(s)) with declining water potential. The percentage loss in hydraulic conductivity (PLC) differed between dehydration and centrifuge curves and it was determined that grapevine is susceptible to errors in estimating maximum K(s) during dehydration because of the development of vessel blockages. Our results from a long-vesselled liana do not support the open vessel artifact hypothesis. © 2012 The Authors. New Phytologist © 2012 New Phytologist Trust.

  1. Strategies to improve retention in randomised trials.

    PubMed

    Brueton, Valerie C; Tierney, Jayne; Stenning, Sally; Harding, Seeromanie; Meredith, Sarah; Nazareth, Irwin; Rait, Greta

    2013-12-03

    Loss to follow-up from randomised trials can introduce bias and reduce study power, affecting the generalisability, validity and reliability of results. Many strategies are used to reduce loss to follow-up and improve retention but few have been formally evaluated. To quantify the effect of strategies to improve retention on the proportion of participants retained in randomised trials and to investigate if the effect varied by trial strategy and trial setting. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PreMEDLINE, EMBASE, PsycINFO, DARE, CINAHL, Campbell Collaboration's Social, Psychological, Educational and Criminological Trials Register, and ERIC. We handsearched conference proceedings and publication reference lists for eligible retention trials. We also surveyed all UK Clinical Trials Units to identify further studies. We included eligible retention trials of randomised or quasi-randomised evaluations of strategies to increase retention that were embedded in 'host' randomised trials from all disease areas and healthcare settings. We excluded studies aiming to increase treatment compliance. We contacted authors to supplement or confirm data that we had extracted. For retention trials, we recorded data on the method of randomisation, type of strategy evaluated, comparator, primary outcome, planned sample size, numbers randomised and numbers retained. We used risk ratios (RR) to evaluate the effectiveness of the addition of strategies to improve retention. We assessed heterogeneity between trials using the Chi(2) and I(2) statistics. For main trials that hosted retention trials, we extracted data on disease area, intervention, population, healthcare setting, sequence generation and allocation concealment. We identified 38 eligible retention trials. Included trials evaluated six broad types of strategies to improve retention. These were incentives, communication strategies, new questionnaire format, participant case

  2. Identification of recruitment and retention strategies for rehabilitation professionals in Ontario, Canada: results from expert panels.

    PubMed

    Tran, Diem; Hall, Linda McGillis; Davis, Aileen; Landry, Michel D; Burnett, Dawn; Berg, Katherine; Jaglal, Susan

    2008-12-09

    Demand for rehabilitation services is expected to increase due to factors such as an aging population, workforce pressures, rise in chronic and complex multi-system disorders, advances in technology, and changes in interprofessional health service delivery models. However, health human resource (HHR) strategies for Canadian rehabilitation professionals are lagging behind other professional groups such as physicians and nurses. The objectives of this study were: 1) to identify recruitment and retention strategies of rehabilitation professionals including occupational therapists, physical therapists and speech language pathologists from the literature; and 2) to investigate both the importance and feasibility of the identified strategies using expert panels amongst HHR and education experts. A review of the literature was conducted to identify recruitment and retention strategies for rehabilitation professionals. Two expert panels, one on Recruitment and Retention and the other on Education were convened to determine the importance and feasibility of the identified strategies. A modified-delphi process was used to gain consensus and to rate the identified strategies along these two dimensions. A total of 34 strategies were identified by the Recruitment and Retention and Education expert panels as being important and feasible for the development of a HHR plan for recruitment and retention of rehabilitation professionals. Seven were categorized under the Quality of Worklife and Work Environment theme, another seven in Financial Incentives and Marketing, two in Workload and Skill Mix, thirteen in Professional Development and five in Education and Training. Based on the results from the expert panels, the three major areas of focus for HHR planning in the rehabilitation sector should include strategies addressing Quality of Worklife and Work Environment, Financial Incentives and Marketing and Professional Development.

  3. Hemodynamic flow visualization of early embryonic great vessels using μPIV.

    PubMed

    Goktas, Selda; Chen, Chia-Yuan; Kowalski, William J; Pekkan, Kerem

    2015-01-01

    Microparticle image velocimetry (μPIV) is an evolving quantitative methodology to closely and accurately monitor the cardiac flow dynamics and mechanotransduction during vascular morphogenesis. While PIV technique has a long history, contemporary developments in advanced microscopy have significantly expanded its power. This chapter includes three new methods for μPIV acquisition in selected embryonic structures achieved through advanced optical imaging: (1) high-speed confocal scanning of transgenic zebrafish embryos, where the transgenic erythrocytes act as the tracing particles; (2) microinjection of artificial seeding particles in chick embryos visualized with stereomicroscopy; and (3) real-time, time-resolved optical coherence tomography acquisition of vitelline vessel flow profiles in chick embryos, tracking the erythrocytes.

  4. Retention strategies in longitudinal studies with emerging adults.

    PubMed

    Hanna, Kathleen M; Scott, Linda L; Schmidt, Karen K

    2014-01-01

    The purpose of this report was to describe retention strategies that were useful and those that were not in a longitudinal study of emerging adults. A longitudinal study examining the transition to young adulthood among emerging adults with type 1 diabetes, which had success in retention, provided the context for describing retention strategies. A challenge in longitudinally designed studies is retention of participants because the loss decreases power for statistical analysis. Given that emerging adulthood is a period of instability, retention is particularly challenging among this population. However, longitudinal studies are the best way to understand developmental changes, and it is also important to increase our knowledge of health outcomes during emerging adulthood. Retention strategies used in the study are described, including promoting a positive relationship with participants, maintaining contact with participants, having a study staff with good interpersonal skills, using incentives, conveying respect for participants, and using user-friendly data collection. Useful strategies to promote a positive relationship included sending cards and newsletters to participants, maintaining consistency of contact person, and expressing appreciation for participant's time and effort. Useful strategies for maintaining contact with participants included obtaining contact information at every data collection point, maintaining birth dates and chart numbers in tracking databases, monitoring returned mail, and using Web search engines. Other useful strategies were providing incentives to participants, employing staff with good interpersonal skills, providing participants with choices when appropriate, and using user-friendly data collection. One strategy, using contests, was not found useful. Despite the challenges of conducting longitudinally designed studies with emerging adults, multiple retention strategies can be used that are useful to retention. It is feasible to

  5. Effects of sodium polyacrylate on water retention and infiltration capacity of a sandy soil.

    PubMed

    Zhuang, Wenhua; Li, Longguo; Liu, Chao

    2013-01-01

    Based on the laboratory study, the effects of sodium polyacrylate (SP) was investigated at 5 rates of 0, 0.08, 0.2, 0.5, and 1%, on water retention, saturated hydraulic conductivity(Ks), infiltration characteristic and water distribution profiles of a sandy soil. The results showed that water retention and available water capacity effectively increased with increasing SP rate. The Ks and the rate of wetting front advance and infiltration under certain pond infiltration was significantly reduced by increasing SP rate, which effectively reduced water in a sandy soil leaking to a deeper layer under the plough layer. The effect of SP on water distribution was obviously to the up layer and very little to the following deeper layers. Considering both the effects on water retention and infiltration capacity, it is suggested that SP be used to the sandy soil at concentrations ranging from 0.2 to 0.5%.

  6. Retention of allied health professionals in rural New South Wales: a thematic analysis of focus group discussions.

    PubMed

    Keane, Sheila; Lincoln, Michelle; Smith, Tony

    2012-06-22

    Uneven distribution of the medical workforce is globally recognised, with widespread rural health workforce shortages. There has been substantial research on factors affecting recruitment and retention of rural doctors, but little has been done to establish the motives and conditions that encourage allied health professionals to practice rurally. This study aims to identify aspects of recruitment and retention of rural allied health professionals using qualitative methodology. Six focus groups were conducted across rural NSW and analysed thematically using a grounded theory approach. The thirty allied health professionals participating in the focus groups were purposively sampled to represent a range of geographic locations, allied health professions, gender, age, and public or private work sectors. Five major themes emerged: personal factors; workload and type of work; continuing professional development (CPD); the impact of management; and career progression. 'Pull factors' favouring rural practice included: attraction to rural lifestyle; married or having family in the area; low cost of living; rural origin; personal engagement in the community; advanced work roles; a broad variety of challenging clinical work; and making a difference. 'Push factors' discouraging rural practice included: lack of employment opportunities for spouses; perceived inadequate quality of secondary schools; age related issues (retirement, desire for younger peer social interaction, and intention to travel); limited opportunity for career advancement; unmanageable workloads; and inadequate access to CPD. Having competent clinical managers mitigated the general frustration with health service management related to inappropriate service models and insufficient or inequitably distributed resources. Failure to fill vacant positions was of particular concern and frustration with the lack of CPD access was strongly represented by informants. While personal factors affecting recruitment and

  7. 33 CFR 151.2020 - Vessels in innocent passage.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Vessels in innocent passage. 151.2020 Section 151.2020 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... United States § 151.2020 Vessels in innocent passage. A foreign vessel that is merely traversing the...

  8. 33 CFR 151.2020 - Vessels in innocent passage.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Vessels in innocent passage. 151.2020 Section 151.2020 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... United States § 151.2020 Vessels in innocent passage. A foreign vessel that is merely traversing the...

  9. 33 CFR 151.2020 - Vessels in innocent passage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Vessels in innocent passage. 151.2020 Section 151.2020 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... United States § 151.2020 Vessels in innocent passage. A foreign vessel that is merely traversing the...

  10. Retention performance of green roofs in three different climate regions

    NASA Astrophysics Data System (ADS)

    Sims, Andrew W.; Robinson, Clare E.; Smart, Charles C.; Voogt, James A.; Hay, Geoffrey J.; Lundholm, Jeremey T.; Powers, Brandon; O'Carroll, Denis M.

    2016-11-01

    Green roofs are becoming increasingly popular for moderating stormwater runoff in urban areas. This study investigated the impact different climates have on the retention performance of identical green roofs installed in London Ontario (humid continental), Calgary Alberta (semi-arid, continental), and Halifax Nova Scotia (humid, maritime). Drier climates were found to have greater percent cumulative stormwater retention with Calgary (67%) having significantly better percent retention than both London (48%) and Halifax (34%). However, over the same study period the green roof in London retained the greatest depth of stormwater (598 mm), followed by the green roof in Halifax (471 mm) and then Calgary (411 mm). The impact of climate was largest for medium sized storms where the antecedent moisture condition (AMC) at the beginning of a rainfall event governs retention performance. Importantly AMC was a very good predictor of stormwater retention, with similar retention at all three sites for a given AMC, emphasizing that AMC is a relevant indicator of retention performance in any climate. For large rainfall events (i.e., >45 mm) green roof average retention ranged between 16% and 29% in all cities. Overall, drier climates have superior retention due to lower AMC in the media. However, moderate and wet climates still provide substantial total volume reduction benefits.

  11. Deuterium Retention and Physical Sputtering of Low Activation Ferritic Steel

    NASA Astrophysics Data System (ADS)

    T, Hino; K, Yamaguchi; Y, Yamauchi; Y, Hirohata; K, Tsuzuki; Y, Kusama

    2005-04-01

    Low activation materials have to be developed toward fusion demonstration reactors. Ferritic steel, vanadium alloy and SiC/SiC composite are candidate materials of the first wall, vacuum vessel and blanket components, respectively. Although changes of mechanical-thermal properties owing to neutron irradiation have been investigated so far, there is little data for the plasma material interactions, such as fuel hydrogen retention and erosion. In the present study, deuterium retention and physical sputtering of low activation ferritic steel, F82H, were investigated by using deuterium ion irradiation apparatus. After a ferritic steel sample was irradiated by 1.7 keV D+ ions, the weight loss was measured to obtain the physical sputtering yield. The sputtering yield was 0.04, comparable to that of stainless steel. In order to obtain the retained amount of deuterium, technique of thermal desorption spectroscopy (TDS) was employed to the irradiated sample. The retained deuterium desorbed at temperature ranging from 450 K to 700 K, in the forms of DHO, D2, D2O and hydrocarbons. Hence, the deuterium retained can be reduced by baking with a relatively low temperature. The fluence dependence of retained amount of deuterium was measured by changing the ion fluence. In the ferritic steel without mechanical polish, the retained amount was large even when the fluence was low. In such a case, a large amount of deuterium was trapped in the surface oxide layer containing O and C. When the fluence was large, the thickness of surface oxide layer was reduced by the ion sputtering, and then the retained amount in the oxide layer decreased. In the case of a high fluence, the retained amount of deuterium became comparable to that of ferritic steel with mechanical polish or SS 316L, and one order of magnitude smaller than that of graphite. When the ferritic steel is used, it is required to remove the surface oxide layer for reduction of fuel hydrogen retention. Ferritic steel sample was

  12. Studies in fat grafting: Part III. Fat grafting irradiated tissue--improved skin quality and decreased fat graft retention.

    PubMed

    Garza, Rebecca M; Paik, Kevin J; Chung, Michael T; Duscher, Dominik; Gurtner, Geoffrey C; Longaker, Michael T; Wan, Derrick C

    2014-08-01

    Following radiation therapy, skin becomes fibrotic and can present a difficult problem for reconstructive surgeons. There is an increasing belief that fat grafting under irradiated skin can reverse the damage caused by radiation. The present study evaluated the effect of fat grafting on irradiated skin, along with fat graft quality and retention rates in irradiated tissue. Nine adult Crl:NU-Foxn1 CD-1 mice underwent 30-Gy external beam irradiation of the scalp. Four weeks after irradiation, scalp skin from irradiated and nonirradiated mice was harvested and compared histologically for dermal thickness, collagen content, and vascular density. Human fat grafts were then injected in the subcutaneous plane of the scalp. Skin assessment was performed in the irradiated group at 2 and 8 weeks after grafting, and fat graft retention was measured at baseline and every 2 weeks up to 8 weeks after grafting using micro-computed tomography. Finally, fat graft samples were explanted at 8 weeks, and quality scoring was performed. Fat grafting resulted in decreased dermal thickness, decreased collagen content, and increased vascular density in irradiated skin. Computed tomographic analysis revealed significantly decreased fat graft survival in the irradiated group compared with the nonirradiated group. Histologic scoring of explanted fat grafts demonstrated no difference in quality between the irradiated and nonirradiated groups. Fat grafting attenuates dermal collagen deposition and vessel depletion characteristic of radiation fibrosis. Although fat graft retention rates are significantly lower in irradiated than in nonirradiated tissue, the quality of retained fat between the groups is similar.

  13. Analysis of the Effect of Environmental Conditions in Conducting Amphibious Assaults Using a Ship Simulator/Vessel-Response Model Proof-of-Concept Study

    DTIC Science & Technology

    2017-05-01

    Analyzing these factors enables a planner to develop an axis-of-advance that a vessel can easily maintain, as well as to reduce the travel time from...operational risk by testing the feasibility of the navigability of an area; 2) determining the capacity and timing of that operation; 3) defining the...conditions at this location dictate that only a narrow window of time is available for conducting surface ship-to- shore operations. The vessel

  14. Urinary Retention Associated with Stroke.

    PubMed

    Umemura, Takeru; Ohta, Hirotsugu; Yokota, Akira; Yarimizu, Shiroh; Nishizawa, Shigeru

    Patients often exhibit urinary retention following a stroke. Various neuropathological and animal studies have implicated the medulla oblongata, pons, limbic system, frontal lobe as areas responsible for micturition control, although the exact area responsible for urinary retention after stroke is not clear. The purpose of this study was to identify the stroke area responsible for urinary retention by localizing the areas where strokes occur. We assessed 110 patients with cerebral infarction and 27 patients with cerebral hemorrhage (78 men, 59 women; mean age, 73.0 years) who had been admitted to our hospital between October, 2012 and September, 2013. We used computed tomography (CT) and magnetic resonance imaging (MRI) to investigate the stroke location, and evaluated whether post-stroke urinary retention occurred. Twelve (8.8%) of the 137 patients (7 men, 5 women; mean age, 78.8 years) exhibited urinary retention after a stroke. Stroke occurred in the right/left dominant hemisphere in 7 patients; nondominant hemisphere in 1; cerebellum in 3; and brainstem in 1. Strokes in the dominant hemisphere were associated with urinary retention (P = 0.0314), particularly in the area of the insula (P < 0.01). We concluded that stroke affecting the insula of the dominant hemisphere tends to cause urinary retention.

  15. Teacher Decision-Making in Student Retention.

    ERIC Educational Resources Information Center

    Cross, Ray

    This investigation at a southern Texas school district examined three factors that bear on teachers' decisions to recommend first- and second-grade students for retention: (1) criteria used by teachers, (2) degree to which criteria are common among teachers, and (3) relationship of recommendations for promotion or retention to objective measures…

  16. Mobile Learning and Student Retention

    ERIC Educational Resources Information Center

    Fozdar, Bharat Inder; Kumar, Lalita S.

    2007-01-01

    Student retention in open and distance learning (ODL) is comparatively poor to traditional education and, in some contexts, embarrassingly low. Literature on the subject of student retention in ODL indicates that even when interventions are designed and undertaken to improve student retention, they tend to fall short. Moreover, this area has not…

  17. [Large vessels vasculopathy in systemic sclerosis].

    PubMed

    Tejera Segura, Beatriz; Ferraz-Amaro, Iván

    2015-12-07

    Vasculopathy in systemic sclerosis is a severe, in many cases irreversible, manifestation that can lead to amputation. While the classical clinical manifestations of the disease have to do with the involvement of microcirculation, proximal vessels of upper and lower limbs can also be affected. This involvement of large vessels may be related to systemic sclerosis, vasculitis or atherosclerotic, and the differential diagnosis is not easy. To conduct a proper and early diagnosis, it is essential to start prompt appropriate treatment. In this review, we examine the involvement of large vessels in scleroderma, an understudied manifestation with important prognostic and therapeutic implications. Copyright © 2015 Elsevier España, S.L.U. All rights reserved.

  18. Lung vessel segmentation in CT images using graph-cuts

    NASA Astrophysics Data System (ADS)

    Zhai, Zhiwei; Staring, Marius; Stoel, Berend C.

    2016-03-01

    Accurate lung vessel segmentation is an important operation for lung CT analysis. Filters that are based on analyzing the eigenvalues of the Hessian matrix are popular for pulmonary vessel enhancement. However, due to their low response at vessel bifurcations and vessel boundaries, extracting lung vessels by thresholding the vesselness is not sufficiently accurate. Some methods turn to graph-cuts for more accurate segmentation, as it incorporates neighbourhood information. In this work, we propose a new graph-cuts cost function combining appearance and shape, where CT intensity represents appearance and vesselness from a Hessian-based filter represents shape. Due to the amount of voxels in high resolution CT scans, the memory requirement and time consumption for building a graph structure is very high. In order to make the graph representation computationally tractable, those voxels that are considered clearly background are removed from the graph nodes, using a threshold on the vesselness map. The graph structure is then established based on the remaining voxel nodes, source/sink nodes and the neighbourhood relationship of the remaining voxels. Vessels are segmented by minimizing the energy cost function with the graph-cuts optimization framework. We optimized the parameters used in the graph-cuts cost function and evaluated the proposed method with two manually labeled sub-volumes. For independent evaluation, we used 20 CT scans of the VESSEL12 challenge. The evaluation results of the sub-volume data show that the proposed method produced a more accurate vessel segmentation compared to the previous methods, with F1 score 0.76 and 0.69. In the VESSEL12 data-set, our method obtained a competitive performance with an area under the ROC curve of 0.975, especially among the binary submissions.

  19. Dual shell pressure balanced vessel

    DOEpatents

    Fassbender, Alexander G.

    1992-01-01

    A dual-wall pressure balanced vessel for processing high viscosity slurries at high temperatures and pressures having an outer pressure vessel and an inner vessel with an annular space between the vessels pressurized at a pressure slightly less than or equivalent to the pressure within the inner vessel.

  20. Roi Detection and Vessel Segmentation in Retinal Image

    NASA Astrophysics Data System (ADS)

    Sabaz, F.; Atila, U.

    2017-11-01

    Diabetes disrupts work by affecting the structure of the eye and afterwards leads to loss of vision. Depending on the stage of disease that called diabetic retinopathy, there are sudden loss of vision and blurred vision problems. Automated detection of vessels in retinal images is a useful study to diagnose eye diseases, disease classification and other clinical trials. The shape and structure of the vessels give information about the severity of the disease and the stage of the disease. Automatic and fast detection of vessels allows for a quick diagnosis of the disease and the treatment process to start shortly. ROI detection and vessel extraction methods for retinal image are mentioned in this study. It is shown that the Frangi filter used in image processing can be successfully used in detection and extraction of vessels.

  1. Does skill retention benefit from retentivity and symbolic rehearsal? - two studies with a simulated process control task.

    PubMed

    Kluge, Annette; Frank, Barbara; Maafi, Sanaz; Kuzmanovska, Aleksandra

    2016-05-01

    Two experiments were designed to compare two symbolic rehearsal refresher interventions (imaginary practice, a hidden introspective process) and investigate the role of retentivity in skill retention. Retentivity is investigated as the ability to memorise and reproduce information and associations that were learned a short time ago. Both experiments comprised initial training (week 1), a symbolic rehearsal for the experimental group (week 2) and a retention assessment (week 3). In the first study, the experimental group received a symbolic rehearsal, while the control group received no rehearsal. In the second study, the experimental group received the same symbolic rehearsal used in study 1, enhanced with rehearsal tasks addressing human-computer interaction. The results showed that both symbolic rehearsal interventions were equally likely to mitigate skill decay. The retentivity showed medium to high correlations with skill retention in both studies, and the results suggest that subjects high in retentivity benefit more from a symbolic rehearsal refresher intervention. Practitioner Summary: Skill decay becomes a problem in situations in which jobs require the correct mastery of non-routine situations. Two experimental studies with simulated process control tasks showed that symbolic rehearsal and retentivity can significantly mitigate skill decay and that subjects higher in retentivity benefit more from refresher interventions.

  2. 48 CFR 52.247-64 - Preference for Privately Owned U.S.-Flag Commercial Vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., materials, or commodities that may be transported in ocean vessels (computed separately for dry bulk..., materials, or commodities, located within or outside the United States, that may be transported by ocean... convertibility of foreign currencies; or (4) Acquired with advance of funds, loans, or guaranties made by or on...

  3. 48 CFR 52.247-64 - Preference for Privately Owned U.S.-Flag Commercial Vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., materials, or commodities that may be transported in ocean vessels (computed separately for dry bulk..., materials, or commodities, located within or outside the United States, that may be transported by ocean... convertibility of foreign currencies; or (4) Acquired with advance of funds, loans, or guaranties made by or on...

  4. Career advancement and educational opportunities: experiences and perceptions of internationally educated nurses.

    PubMed

    Salma, Jordana; Hegadoren, Kathleen M; Ogilvie, Linda

    2012-01-01

    The number of internationally educated nurses is increasing in the Canadian workforce. Recruitment of internationally educated nurses is often seen as a solution to ongoing nursing shortages. However, international recruitment needs to be accompanied by strategies to ensure long-term retention. One of the criteria for successful retention is the availability and accessibility of career advancement and educational opportunities. Little research exists on the opportunities for career advancement and education for internationally educated nurses in Canada. This interpretive descriptive study was conducted to look at the perceptions of internationally educated nurses regarding career advancement and educational opportunities in Alberta, Canada. Eleven internationally educated nurses, working as registered nurses in Alberta, were interviewed using semi-structured interviews. Five themes were identified: motherhood as a priority, communication and cultural challenges, process of skill recognition, perceptions of opportunity and need for mentorship.

  5. Autoradiographic and histopathological studies of boric acid-mediated BNCT in hepatic VX2 tumor-bearing rabbits: Specific boron retention and damage in tumor and tumor vessels.

    PubMed

    Yang, C H; Lin, Y T; Hung, Y H; Liao, J W; Peir, J J; Liu, H M; Lin, Y L; Liu, Y M; Chen, Y W; Chuang, K S; Chou, F I

    2015-12-01

    Hepatoma is a malignant tumor that responds poorly to conventional therapies. Boron neutron capture therapy (BNCT) may provide a better way for hepatoma therapy. In this research, (10)B-enriched boric acid (BA, 99% (10)B) was used as the boron drug. A multifocal hepatic VX2 tumor-bearing rabbit model was used to study the mechanisms of BA-mediated BNCT. Autoradiography demonstrated that BA was selectively targeted to tumors and tumor vessels. Histopathological examination revealed the radiation damage to tumor-bearing liver was concentrated in the tumor regions during BNCT treatment. The selective killing of tumor cells and the destruction of the blood vessels in tumor masses may be responsible for the success of BA-mediated BNCT for liver tumors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Ecosystem Nitrogen Retention Following Severe Bark Beetle and Salvage Logging Disturbance in Lodgepole Pine Forests: a 15N Enrichment Study

    NASA Astrophysics Data System (ADS)

    Avera, B.; Rhoades, C.; Paul, E. A.; Cotrufo, M. F.

    2017-12-01

    In recent decades, bark beetle outbreaks have caused high levels of tree mortality in lodgepole pine (Pinus contorta) dominated forests across western North America. Previous work has found increased soil mineral nitrogen (N) with tree mortality in beetle infested stands, but surprisingly little change in stream N export. These findings suggest an important role of residual live vegetation and altered soil microbial response for retaining surplus N and mitigating N losses from disturbed lodgepole forests. Post outbreak salvage of merchantable timber reduces fuel levels and promotes tree regeneration; however, the implications of the combined bark beetle and harvesting disturbances on ecosystem N retention and productivity are uncertain. To advance understanding of post-disturbance N retention we compare unlogged beetle-infested forests and salvage logged stands with post-harvest woody residue retention or removal. We applied 15N-labeled (2 atom%) and natural abundance ammonium sulfate to eight year old lodgepole pine seedlings in three replicate plots of the three forest management treatments. This approach allows us to quantify the relative contributions of N retention in soil, microbial biomass, and plant tissue. Our study targets gaps in understanding of the processes that regulate N utilization and transfer between soil and vegetation that result in effective N retention in lodgepole pine ecosystems. These findings will also help guide forest harvest and woody residue management practices in order to maintain soil productivity.

  7. Lymphatic and blood vessels in male breast cancer.

    PubMed

    Niemiec, Joanna; Sas-Korczynska, Beata; Harazin-Lechowska, Agnieszka; Martynow, Dariusz; Adamczyk, Agnieszka

    2015-02-01

    It is assumed that lymphatic vessels are responsible for breast cancer dissemination. In 32 male breast carcinomas we evaluated the correlation between: (i) lymphatic vessel density (LVD), distribution of podoplanin-immunostained vessels (DPV), blood vessel density (BVD), infiltration of immune cells and (ii) known clinicopathological parameters. Lymphatic and blood vessels were found in 77.8% and 100% of breast carcinomas, respectively. Double-negative estrogen and progesterone receptor tumors (ER-/PR-) presented significantly higher LVD than ER/PR positive cases, while high-grade tumors exhibited significantly higher DPV than low-grade carcinomas. We detected significantly higher frequency of vascular invasion in high-grade and double-negative carcinomas than in low-grade and ER/PR-positive ones, respectively. The relationship between high number of lymphatic vessels and high tumor grade or steroid receptor negativity might confirm the hypothesis regarding the influence of lymphangiogenesis on the formation of a more aggressive phenotype in male breast cancer. Copyright© 2015 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  8. “That’s a good question”: University researchers’ views on ownership and retention of human genetic specimens

    PubMed Central

    Cadigan, R. Jean; Easter, Michele M.; Dobson, Allison W.; Davis, Arlene M.; Rothschild, Barbra B.; Zimmer, Catherine; Sterling, Rene; Henderson, Gail

    2012-01-01

    Purpose To explore the views of university-based investigators conducting genetic research with human specimens regarding ownership and retention of specimens, and knowledge of related institutional review board and university policies. Methods Data were collected in three phases: a qualitative pilot study of 14 investigators; a web-based survey taken by 80 investigators; and follow-up, in-depth interviews with 12 survey respondents. Results Investigators named a variety of single or multiple owners of human specimens and often expressed confusion regarding specimen ownership. Most associated ownership with rights to control, and responsibilities to maintain, specimens. Investigators viewed specimens as “precious” resources whose value could be increased through long-term or infinite retention, particularly in light of anticipated technological advances in genome science. Their views on ownership and retention were shaped by perceptions of institutional review board policies as immortalized in subject informed consent documents, rather than knowledge of actual policies. Conclusion Long-term retention of human specimens makes confusion about ownership particularly problematic. Given findings that investigators’ views on ownership and retention are largely guided by their perception of university policies, the need for clear, consistent policies at the institution level is urgent. PMID:21659952

  9. To Evaluate & Compare Retention of Complete Cast Crown in Natural Teeth Using Different Auxiliary Retentive Features with Two Different Crown Heights - An In Vitro Study.

    PubMed

    Vinaya, Kundapur; Rakshith, Hegde; Prasad D, Krishna; Manoj, Shetty; Sunil, Mankar; Naresh, Shetty

    2015-06-01

    To evaluate the retention of complete cast crowns in teeth with adequate and inadequate crown height and to evaluate the effects of auxiliary retentive features on retention form complete cast crowns. Sixty freshly extracted human premolars. They were divided into 2 major groups depending upon the height of the teeth after the preparation. Group1 (H1): prepared teeth with constant height of 3.5 mm and Group 2 (H2): prepared teeth with constant height of 2.5 mm. Each group is further subdivided into 3 subgroups, depending upon the retentive features incorporated. First sub group were prepared conventionally, second sub group with proximal grooves and third subgroups with proximal boxes preparation. Castings produced in Nickel chromium alloy were cemented with glass ionomer cement and the cemented castings were subjected to tensional forces required to dislodge each cemented casting from its preparation and used for comparison of retentive quality. The data obtained were statistically analyzed using Oneway ANOVA test. The results showed there was statistically significant difference between adequate (H1) and inadequate (H2) group and increase in retention when there was incorporation of retentive features compared to conventional preparations. Incorporation of retentive grooves was statistically significant compared to retention obtained by boxes. Results also showed there was no statistically significant difference between long conventional and short groove. Complete cast crowns on teeth with adequate crown height exhibited greater retention than with inadequate crown height. Proximal grooves provided greater amount of retention when compared with proximal boxes.

  10. New Experimental Results on the Interaction of Molten Corium with Reactor Vessel Steel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bechta, S.V.; Khabensky, V.B.; Granovsky, V.S.

    In order to justify the concept of in-vessel core melt retention, it is necessary to understand the thermal and physico-chemical phenomena. Especially the interaction of the molten pool with the reactor vessel during outside cooling needs to be understood. These phenomena are very complex, in particular, where interactions with the oxidic melt are concerned. In the early stages of the retention process, the oxidic corium and the vessel steel interact under the conditions of low oxygen potential in the melt. These conditions can be simulated by a molten corium having the composition UO{sub 2}/ZrO{sub 2}/Zr, where the degree of Zr-oxidationmore » is in the range between 30 % (C-30) and 100 % (C-100). Corresponding experiments with prototypic melts at low oxygen potentials are being performed in the ISTC METCOR project 2. phase. These are: - MC 5 of corium composition 71w%UO{sub 2}-29w%ZrO{sub 2} (C-100) in neutral atmosphere (argon), - MC 6 of corium composition 76w%UO{sub 2}-9w%ZrO{sub 2}-15w%Zr (C{approx}30), also in argon. In test MC 5, the interaction of molten C-100 corium with a water-cooled steel specimen was studied for the following maximum temperatures at the specimen surface: 1075 deg. C, 1180 deg. C, 1315 deg. C and 1435 deg. C. The total duration of the experiment was {approx} 36 hours. The MC 5 test serves as a reference test for determining the characteristics of the interaction between oxidic melt and steel specimen under the conditions of minimum chemical interaction potential. To investigate the effect of substoichiometry, test No 6 was then performed with sub-oxidized molten corium C{approx}30. The maximum surface temperature of the cooled steel specimen was held at {approx} 1400 deg. C. The test duration was {approx} 10 hours. The ablation phenomena were found to differ significantly from those observed both in the reference test, as well as in former tests with oxidized melts, as they involved the formation of a low-melting metallic phase at

  11. Discontinuity stresses in metallic pressure vessels

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The state of the art, criteria, and recommended practices for the theoretical and experimental analyses of discontinuity stresses and their distribution in metallic pressure vessels for space vehicles are outlined. The applicable types of pressure vessels include propellant tanks ranging from main load-carrying integral tank structure to small auxiliary tanks, storage tanks, solid propellant motor cases, high pressure gas bottles, and pressurized cabins. The major sources of discontinuity stresses are discussed, including deviations in geometry, material properties, loads, and temperature. The advantages, limitations, and disadvantages of various theoretical and experimental discontinuity analysis methods are summarized. Guides are presented for evaluating discontinuity stresses so that pressure vessel performance will not fall below acceptable levels.

  12. 78 FR 77430 - Proposed Information Collection; Comment Request; Foreign Fishing Vessel Permits, Vessel, and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-23

    ... Collection; Comment Request; Foreign Fishing Vessel Permits, Vessel, and Gear Identification, and Reporting..., vessels and certain gear be marked for identification purposes, and for permit holders to report their... information for a permit, mark their vessels and gear, or submit information about their fishing activities...

  13. Enhancement of deuterium retention in damaged tungsten by plasma-induced defect clustering

    NASA Astrophysics Data System (ADS)

    Jin, Younggil; Roh, Ki-Baek; Sheen, Mi-Hyang; Kim, Nam-Kyun; Song, Jaemin; Kim, Young-Woon; Kim, Gon-Ho

    2017-12-01

    The enhancement of deuterium retention was investigated for tungsten in the presence of both 2.8 MeV self-ion induced cascade damage and fuel hydrogen isotope plasma. Vacancy clustering in cascade damaged polycrystalline tungsten occurred due to deuterium irradiation and was observed near the grain boundary by using all-step transmission electron microscopy analysis. Analysis of the highest desorption temperature peak using thermal desorption spectroscopy supports reasonable evidence of defect clustering in the damaged polycrystalline tungsten. The defect clustering was neither observed on the damaged polycrystalline tungsten without deuterium irradiation nor on the damaged single-crystalline tungsten with deuterium irradiation. This result implies the synergetic role of deuterium and grain boundary on defect clustering. This study proposes a path for the defect transform from point defect to defect cluster, by the agglomeration between irradiated deuterium and cascade damage-induced defect. This agglomeration may induce more severe damage on the tungsten divertor at which the high fuel hydrogen ions, fast neutrons, and self-ions are irradiated simultaneously and it would increase the in-vessel tritium inventory.

  14. Advances in the design of common pressure vessel nickel hydrogen batteries for aerospace applications

    NASA Technical Reports Server (NTRS)

    Zagrodnik, Jeffrey P.; Jones, Kenneth R.

    1991-01-01

    Over 7000 low-earth-orbit (LEO) cycles were demonstrated on a full-size aerospace common pressure vessel (CPV) prototype. The battery demonstrated the capability of the basic CPV design to meet the life and reliability requirements of aerospace missions. Subsequent design modifications have been employed to address the shortcomings of the original design and several new prototypes have been fabricated. These include a 12-cell 125 amp-hour geosynchronous earth-orbit (GEO) battery and a 22-cell 10.5 amp-hour LEO battery. Cells for an 80-cell battery intended to demonstrate the high voltage capability of the CPV design have also been fabricated. In addition, assembly of a 20-cell aircraft starting battery prototype is in progress, and testing of a group of 12-volt, 160 amp-hour terrestrial batteries is continuing.

  15. 5 CFR 536.301 - Mandatory pay retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Mandatory pay retention. 536.301 Section... PAY RETENTION Pay Retention § 536.301 Mandatory pay retention. (a) Subject to the requirements in § 536.102 and this section, an agency must provide pay retention to an employee who moves between...

  16. 46 CFR 169.119 - Vessel status.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Vessel status. 169.119 Section 169.119 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS General.... 883 a sailing school vessel is not deemed a merchant vessel or a vessel engaged in trade or commerce. ...

  17. 46 CFR 169.119 - Vessel status.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Vessel status. 169.119 Section 169.119 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS General.... 883 a sailing school vessel is not deemed a merchant vessel or a vessel engaged in trade or commerce. ...

  18. Principles of recruitment and retention in clinical trials.

    PubMed

    Aitken, Leanne; Gallagher, Robyn; Madronio, Christine

    2003-12-01

    Efficient and effective recruitment and retention of participants is the largest single component of the study workload and forms an essential component in the conduct of clinical trials. In this paper, we present five principles to guide the processes of both recruitment and retention. These principles include the selection of an appropriate population to adequately answer the research question, followed by the establishment of a sampling process that accurately represents that population. Creation of systematic and effective recruitment mechanisms should be supported by implementation of follow-up mechanisms that promote participant retention. Finally, all activities related to recruitment and retention must be conducted within the framework of ethics and privacy regulations. Adherence to these principles will assist the researcher in achieving the goals of the study within the available resources.

  19. Studies on in-vessel debris coolability in ALPHA program

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maruyama, Yu; Yamano, Norihiro; Moriyama, Kiyofumi

    1997-02-01

    In-vessel debris coolability experiments have been performed in ALPHA Program at JAERI. Aluminum oxide (Al{sub 2}O{sub 3}) produced by a thermite reaction was applied as a debris simulant. Two scoping experiments using approximately 30 kg or 50 kg of Al{sub 2}O{sub 3} were conducted. In addition to post-test observations, temperature histories of the debris simulant and the lower head experimental vessel were evaluated. Rapid temperature reduction observed on the outer surface of the experimental vessel may imply that water penetration into a gap between the solidified debris and the experimental vessel occurred resulting in an effective cooling of once heatedmore » vessel wall. Preliminary measurement of a gap width was made with an ultrasonic device. Signals to show the existence of gaps, ranging from 0.7 mm to 1.4 mm, were detected at several locations.« less

  20. Teacher Retention: Problems and Solutions

    ERIC Educational Resources Information Center

    McLaurin, Sidney E.; Smith, Willis; Smillie, Amanda

    2009-01-01

    There is a teacher retention crisis in the United States. The purpose of this paper is to answer the following questions: What contributes to teachers leaving the field? How has "No Child Left Behind" affected teacher retention? What can be done to retain good teachers? What impact do school administrators have on teacher retention?…

  1. Advanced nickel-hydrogen spacecraft battery development

    NASA Technical Reports Server (NTRS)

    Coates, Dwaine K.; Fox, Chris L.; Standlee, D. J.; Grindstaff, B. K.

    1994-01-01

    Eagle-Picher currently has several advanced nickel-hydrogen (NiH2) cell component and battery designs under development including common pressure vessel (CPV), single pressure vessel (SPV), and dependent pressure vessel (DPV) designs. A CPV NiH2 battery, utilizing low-cost 64 mm (2.5 in.) cell diameter technology, has been designed and built for multiple smallsat programs, including the TUBSAT B spacecraft which is currently scheduled (24 Nov. 93) for launch aboard a Russian Proton rocket. An advanced 90 mm (3.5 in.) NiH2 cell design is currently being manufactured for the Space Station Freedom program. Prototype 254 mm (10 in.) diameter SPV batteries are currently under construction and initial boilerplate testing has shown excellent results. NiH2 cycle life testing is being continued at Eagle-Picher and IPV cells have currently completed more than 89,000 accelerated LEO cycles at 15% DOD, 49,000 real-time LEO cycles at 30 percent DOD, 37,800 cycles under a real-time LEO profile, 30 eclipse seasons in accelerated GEO, and 6 eclipse seasons in real-time GEO testing at 75 percent DOD maximum. Nickel-metal hydride battery development is continuing for both aerospace and electric vehicle applications. Eagle-Picher has also developed an extensive range of battery evaluation, test, and analysis (BETA) measurement and control equipment and software, based on Hewlett-Packard computerized data acquisition/control hardware.

  2. Identification of recruitment and retention strategies for rehabilitation professionals in Ontario, Canada: results from expert panels

    PubMed Central

    Tran, Diem; Hall, Linda McGillis; Davis, Aileen; Landry, Michel D; Burnett, Dawn; Berg, Katherine; Jaglal, Susan

    2008-01-01

    Background Demand for rehabilitation services is expected to increase due to factors such as an aging population, workforce pressures, rise in chronic and complex multi-system disorders, advances in technology, and changes in interprofessional health service delivery models. However, health human resource (HHR) strategies for Canadian rehabilitation professionals are lagging behind other professional groups such as physicians and nurses. The objectives of this study were: 1) to identify recruitment and retention strategies of rehabilitation professionals including occupational therapists, physical therapists and speech language pathologists from the literature; and 2) to investigate both the importance and feasibility of the identified strategies using expert panels amongst HHR and education experts. Methods A review of the literature was conducted to identify recruitment and retention strategies for rehabilitation professionals. Two expert panels, one on Recruitment and Retention and the other on Education were convened to determine the importance and feasibility of the identified strategies. A modified-delphi process was used to gain consensus and to rate the identified strategies along these two dimensions. Results A total of 34 strategies were identified by the Recruitment and Retention and Education expert panels as being important and feasible for the development of a HHR plan for recruitment and retention of rehabilitation professionals. Seven were categorized under the Quality of Worklife and Work Environment theme, another seven in Financial Incentives and Marketing, two in Workload and Skill Mix, thirteen in Professional Development and five in Education and Training. Conclusion Based on the results from the expert panels, the three major areas of focus for HHR planning in the rehabilitation sector should include strategies addressing Quality of Worklife and Work Environment, Financial Incentives and Marketing and Professional Development. PMID:19068134

  3. Tritium retention in reduced-activation ferritic/martensitic steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hatano, Y.; Abe, S.; Matsuyama, M.

    Reduced-activation ferritic/martensitic (RAFM) steels are structural material candidates for breeding blankets of future fusion reactors. Therefore, tritium (T) retention in RAFM steels is an important problem in assessing the T inventory of blankets. In this study, specimens of RAFM steels were subjected to irradiation of 20 MeV W ions to 0.54 displacements per atom (dpa), exposure to high flux D plasmas at 400 and 600 K and that to pulsed heat loads. The specimens thus prepared were exposed to DT gas at 473 K. Despite severe modification in the surface morphology, heat loads had negligible effects on T retention. Significantmore » increase in T retention at the surface and/or subsurface was observed after D plasma exposure. However, T trapped at the surface/subsurface layer was easily removed by maintaining the specimens in the air at about 300 K. Displacement damage led to increase in T retention in the bulk due to the trapping effects of defects, and T trapped was stable at 300 K. It was therefore concluded that displacement damages had the largest influence on T retention under the present conditions.« less

  4. 76 FR 59660 - Proposed Information Collection; Comment Request; Permitting, Vessel Identification, and Vessel...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-27

    ... DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration Proposed Information Collection; Comment Request; Permitting, Vessel Identification, and Vessel Monitoring System Requirements for... satellite- based vessel monitoring system (VMS). This collection of information is needed for permit...

  5. Job embeddedness and nurse retention.

    PubMed

    Reitz, O Ed; Anderson, Mary Ann; Hill, Pamela D

    2010-01-01

    Nurse retention is a different way of conceptualizing the employer-employee relationship when compared with turnover. Job embeddedness (JE), a construct based on retention, represents the sum of reasons why employees remain at their jobs. However, JE has not been investigated in relation to locale (urban or rural) or exclusively with a sample of registered nurses (RNs). The purpose of this study was to determine what factors (JE, age, gender, locale, and income) help predict nurse retention. A cross-sectional mailed survey design was used with RNs in different locales (urban or rural). Job embeddedness was measured by the score on the composite, standardized instrument. Nurse retention was measured by self-report items concerning intent to stay. A response rate of 49.3% was obtained. The typical respondent was female (96.1%), white, non-Hispanic (87.4%), and married (74.9%). Age and JE were predictive of nurse retention and accounted for 26% of the explained variance in intent to stay. Although age was a significant predictor of intent to stay, it accounted for only 1.4% of the variance while JE accounted for 24.6% of the variance of nurse retention (as measured by intent to stay). Older, more "embedded" nurses are more likely to remain employed in their current organization. Based on these findings, JE may form the basis for the development of an effective nurse retention program.

  6. Vessel-to-Reef Projects

    EPA Pesticide Factsheets

    Using vessels as artificial reefs is an option for disposal. Artificial reefs serve to benefit the environment. Vessel-to-reef projects can follow the best management practices guidance. Guidance are provided for how to clean up vessels for use as reefs.

  7. Flavonoids from Litsea japonica Inhibit AGEs Formation and Rat Lense Aldose Reductase In Vitro and Vessel Dilation in Zebrafish.

    PubMed

    Lee, Ik-Soo; Kim, Yu Jin; Jung, Seung-Hyun; Kim, Joo-Hwan; Kim, Jin Sook

    2017-02-01

    In our ongoing efforts to identify effective naturally sourced agents for the treating of diabetic complications, two new ( 1 and 2 ) and 11 known phenolic compounds ( 3 - 13 ) were isolated from an 80 % ethanol extract of Litsea japonica leaves. The structures of the new compounds were established by spectroscopic and chemical studies. These isolates ( 1 - 13 ) were subjected to an in vitro bioassay evaluating their inhibitory activity on advanced glycation end products formation and rat lens aldose reductase activity. Of the compounds evaluated, the flavonoids ( 3, 4, 6 - 8, 11 , and 12 ) markedly inhibited advanced glycation end products formation, with IC 50 values of 7.4-72.0 µM, compared with the positive control, aminoguanidine (IC 50  = 975.9 µM). In the rat lens aldose reductase assay, consistent with the inhibition of advanced glycation end products formation, the flavonoids ( 3, 4, 6 - 8, 11 , and 12 ) exhibited considerable inhibition of rat lens aldose reductase activity, with IC 50 values of 1.1-12.5 µM. In addition, the effects of kaempferol ( 4 ) and tiliroside ( 7 ) on the dilation of hyaloid-retinal vessels induced by high glucose in larval zebrafish were investigated. Only kaempferol significantly reduced the diameters of high glucose-induced hyaloid-retinal vessels, by 52.2 % at 10 µM, compared with those in the high glucose-treated control group. Georg Thieme Verlag KG Stuttgart · New York.

  8. Containment vessel drain system

    DOEpatents

    Harris, Scott G.

    2018-01-30

    A system for draining a containment vessel may include a drain inlet located in a lower portion of the containment vessel. The containment vessel may be at least partially filled with a liquid, and the drain inlet may be located below a surface of the liquid. The system may further comprise an inlet located in an upper portion of the containment vessel. The inlet may be configured to insert pressurized gas into the containment vessel to form a pressurized region above the surface of the liquid, and the pressurized region may operate to apply a surface pressure that forces the liquid into the drain inlet. Additionally, a fluid separation device may be operatively connected to the drain inlet. The fluid separation device may be configured to separate the liquid from the pressurized gas that enters the drain inlet after the surface of the liquid falls below the drain inlet.

  9. 50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...

  10. 50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...

  11. 50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...

  12. 50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...

  13. 50 CFR 300.116 - Requirements for a vessel monitoring system for U.S. vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... system for U.S. vessels. 300.116 Section 300.116 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED... vessel monitoring system for U.S. vessels. (a) Requirement for use. Within 30 days after NMFS publishes... for AMLR must ensure that such vessel has a NMFS-approved, operating VMS on board when on any fishing...

  14. 19 CFR 4.5 - Government vessels.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...

  15. 19 CFR 4.5 - Government vessels.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...

  16. 19 CFR 4.5 - Government vessels.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...

  17. 19 CFR 4.5 - Government vessels.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...

  18. 19 CFR 4.5 - Government vessels.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Government vessels. 4.5 Section 4.5 Customs Duties... VESSELS IN FOREIGN AND DOMESTIC TRADES Arrival and Entry of Vessels § 4.5 Government vessels. (a) No... that is the property of, the U.S. Department of Defense (DoD) will be treated as a Government vessel...

  19. Novel Word Retention in Sequential Bilingual Children

    ERIC Educational Resources Information Center

    Kan, Pui Fong

    2014-01-01

    Children's ability to learn and retain new words is fundamental to their vocabulary development. This study examined word retention in children learning a home language (L1) from birth and a second language (L2) in preschool settings. Participants were presented with sixteen novel words in L1 and in L2 and were tested for retention after…

  20. Calculation of Retention Time Tolerance Windows with Absolute Confidence from Shared Liquid Chromatographic Retention Data

    PubMed Central

    Boswell, Paul G.; Abate-Pella, Daniel; Hewitt, Joshua T.

    2015-01-01

    Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user’s system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called “retention projection” was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. PMID:26292624

  1. Calculation of retention time tolerance windows with absolute confidence from shared liquid chromatographic retention data.

    PubMed

    Boswell, Paul G; Abate-Pella, Daniel; Hewitt, Joshua T

    2015-09-18

    Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user's system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called "retention projection" was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. IAEA international studies on irradiation embrittlement of reactor pressure vessel steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brumovsky, M.; Steele, L.E.

    1997-02-01

    In last 25 years, three phases a Co-operative Research Programme on Irradiation Embrittlement of Reactor Pressure Vessel Steels has been organized by the International Atomic Energy Agency. This programme started with eight countries in 1971 and finally 16 countries took part in phase III of the Programme in 1983. Several main efforts were put into preparation of the programme, but the principal task was concentrated on an international comparison of radiation damage characterization by different laboratories for steels of {open_quotes}old{close_quotes} (with high impurity contents) and {open_quotes}advanced{close_quotes} (with low impurity contents) types as well as on development of small scale fracturemore » mechanics procedures applicable to reactor pressure vessel surveillance programmes. This year, a new programme has been opened, concentrated mostly on small scale fracture mechanics testing.« less

  3. Long-term fuel retention in JET ITER-like wall

    NASA Astrophysics Data System (ADS)

    Heinola, K.; Widdowson, A.; Likonen, J.; Alves, E.; Baron-Wiechec, A.; Barradas, N.; Brezinsek, S.; Catarino, N.; Coad, P.; Koivuranta, S.; Krat, S.; Matthews, G. F.; Mayer, M.; Petersson, P.; Contributors, JET

    2016-02-01

    Post-mortem studies with ion beam analysis, thermal desorption, and secondary ion mass spectrometry have been applied for investigating the long-term fuel retention in the JET ITER-like wall components. The retention takes place via implantation and co-deposition, and the highest retention values were found to correlate with the thickness of the deposited impurity layers. From the total amount of retained D fuel over half was detected in the divertor region. The majority of the retained D is on the top surface of the inner divertor, whereas the least retention was measured in the main chamber on the mid-plane of the inner wall limiter. The recessed areas of the inner wall showed significant contribution to the main chamber total retention. Thermal desorption spectroscopy analysis revealed the energetic T from DD reactions being implanted in the divertor. The total T inventory was assessed to be \\gt 0.3 {{mg}}.

  4. Retention of pharmaceutical residues and microorganisms at the Altendorf retention soil filter.

    PubMed

    Christoffels, E; Mertens, F M; Kistemann, T; Schreiber, C

    2014-01-01

    A study has been conducted on a retention soil filter (RSF) to test its effectiveness in removing pharmaceutical residues and microorganisms from combined sewer overflows (CSOs). Efficient removal of solids, nutrients and heavy metals has already been proven. The possibility that organic micropollutants and microorganisms are also retained by the use of RSFs has been identified, but data are lacking. Results obtained in this study, in which testing for removal by a RSF of numerous micro-pollutant substances was performed, are most promising. The pharmaceuticals diclofenac and ibuprofen are presented in detail as examples of such micropollutants. Both showed a reduction in positive samples of more than 55% as well as a significant reduction in median and maximum concentrations. For microorganisms such as Escherichia coli, coliphages and Giardia lamblia (cysts), an average reduction in concentrations by three logarithmic steps (99.9%) was achieved. These results add to the evidence that using a RSF in the advanced treatment of wastewater from CSOs reduces the exposure of water-courses to pharmaceutical residues and microbial contamination.

  5. Triamcinolone Acetonide Selectively Inhibits Angiogenesis in Small Blood Vessels and Decreases Vessel Diameter within the Vascular Tree

    NASA Technical Reports Server (NTRS)

    McKay, Terri L.; Gredeon, Dan J.; Vickerman, Mary B.; Hylton, alan G.; Ribita, Daniela; Olar, Harry H.; Kaiser, Peter K.; Parsons-Wingerter, Patricia

    2007-01-01

    The steroid triamcinolone acetonide (TA) is a potent anti-angiogenesis drug used to treat retinal vascular diseases that include diabetic retinopathy, vascular occlusions and choroidal neovascularization. To quantify the effects of TA on branching morphology within the angiogenic microvascular tree of the chorioallantoic membrane (CAM) of quail embryos. Increasing concentrations of TA (0-16 ng/ml) were applied topically on embryonic day 7 (E7) to the chorioallantoic membrane (CAM) of quail embryos cultured in Petri dishes, and incubated for an additional 24 or 48 hours until fixation. Binary (black/white) microscopic images of arterial end points were quantified by VESGEN software (for Generational Analysis of Vessel Branching) to obtain major vascular parameters that include vessel diameter (Dv), fractal dimension (Df), tortuosity (Tv) and densities of vessel area, length, number and branch point (Av, Lv, Nv and Brv). For assessment of specific changes in vascular morphology induced by TA, the VESGEN software automatically segmented the vascular tree into branching generations (G1...G10) according to changes in vessel diameter and branching. Vessel density decreased significantly up to 34% as the function of increasing concentration of TA according to Av, Lv, Brv, Nv and Df. TA selectively inhibited the growth of new, small vessels, because Lv decreased from 13.14plus or minus 0.61 cm/cm2 for controls to 8.012 plus or minus 0.82 cm/cm2 at 16 ng TA/ml in smaller branching generations (G7-G10), and for Nv from 473.83 plus or minus 29.85 cm(-)2 to 302.32 plus or minus 33.09 cm-()2. In contrast, vessel diameter (Dv) decreased throughout the vascular tree (G1-G10).

  6. A Review of Large-Scale Fracture Experiments Relevant to Pressure Vessel Integrity Under Pressurized Thermal Shock Conditions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pugh, C.E.

    2001-01-29

    Numerous large-scale fracture experiments have been performed over the past thirty years to advance fracture mechanics methodologies applicable to thick-wall pressure vessels. This report first identifies major factors important to nuclear reactor pressure vessel (RPV) integrity under pressurized thermal shock (PTS) conditions. It then covers 20 key experiments that have contributed to identifying fracture behavior of RPVs and to validating applicable assessment methodologies. The experiments are categorized according to four types of specimens: (1) cylindrical specimens, (2) pressurized vessels, (3) large plate specimens, and (4) thick beam specimens. These experiments were performed in laboratories in six different countries. This reportmore » serves as a summary of those experiments, and provides a guide to references for detailed information.« less

  7. Easy Come, Easy Go: Capillary Forces Enable Rapid Refilling of Embolized Primary Xylem Vessels.

    PubMed

    Rolland, Vivien; Bergstrom, Dana M; Lenné, Thomas; Bryant, Gary; Chen, Hua; Wolfe, Joe; Holbrook, N Michele; Stanton, Daniel E; Ball, Marilyn C

    2015-08-01

    Protoxylem plays an important role in the hydraulic function of vascular systems of both herbaceous and woody plants, but relatively little is known about the processes underlying the maintenance of protoxylem function in long-lived tissues. In this study, embolism repair was investigated in relation to xylem structure in two cushion plant species, Azorella macquariensis and Colobanthus muscoides, in which vascular water transport depends on protoxylem. Their protoxylem vessels consisted of a primary wall with helical thickenings that effectively formed a pit channel, with the primary wall being the pit channel membrane. Stem protoxylem was organized such that the pit channel membranes connected vessels with paratracheal parenchyma or other protoxylem vessels and were not exposed directly to air spaces. Embolism was experimentally induced in excised vascular tissue and detached shoots by exposing them briefly to air. When water was resupplied, embolized vessels refilled within tens of seconds (excised tissue) to a few minutes (detached shoots) with water sourced from either adjacent parenchyma or water-filled vessels. Refilling occurred in two phases: (1) water refilled xylem pit channels, simplifying bubble shape to a rod with two menisci; and (2) the bubble contracted as the resorption front advanced, dissolving air along the way. Physical properties of the protoxylem vessels (namely pit channel membrane porosity, hydrophilic walls, vessel dimensions, and helical thickenings) promoted rapid refilling of embolized conduits independent of root pressure. These results have implications for the maintenance of vascular function in both herbaceous and woody species, because protoxylem plays a major role in the hydraulic systems of leaves, elongating stems, and roots. © 2015 American Society of Plant Biologists. All Rights Reserved.

  8. Quantitative structure-retention relationships for gas chromatographic retention indices of alkylbenzenes with molecular graph descriptors.

    PubMed

    Ivanciuc, O; Ivanciuc, T; Klein, D J; Seitz, W A; Balaban, A T

    2001-02-01

    Quantitative structure-retention relationships (QSRR) represent statistical models that quantify the connection between the molecular structure and the chromatographic retention indices of organic compounds, allowing the prediction of retention indices of novel, not yet synthesized compounds, solely from their structural descriptors. Using multiple linear regression, QSRR models for the gas chromatographic Kováts retention indices of 129 alkylbenzenes are generated using molecular graph descriptors. The correlational ability of structural descriptors computed from 10 molecular matrices is investigated, showing that the novel reciprocal matrices give numerical indices with improved correlational ability. A QSRR equation with 5 graph descriptors gives the best calibration and prediction results, demonstrating the usefulness of the molecular graph descriptors in modeling chromatographic retention parameters. The sequential orthogonalization of descriptors suggests simpler QSRR models by eliminating redundant structural information.

  9. Assessing Potential Additional PFAS Retention Processes in the Subsurface

    NASA Astrophysics Data System (ADS)

    Brusseau, M. L.

    2017-12-01

    Understanding the transport and fate of per- and poly-fluorinated alkyl substances (PFASs) in the subsurface is critical for accurate risk assessments and design of effective remedial actions. Current conceptual and mathematical models are based on an assumption that solid-phase adsorption is the sole source of retention for PFASs. However, additional retention processes may be relevant for PFAS compounds in vadose-zone systems and in source zones that contain trapped immiscible organic liquids. These include adsorption at the air-water interface, partitioning to the soil atmosphere, adsorption at the NAPL-water interface, and absorption by NAPL. A multi-process retention model is proposed to account for these potential additional sources of PFAS retardation. An initial assessment of the relative magnitudes and significance of these retention processes was conducted for three representative PFASs, perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and 8:2 fluorotelomer alcohol (FTOH). Data collected from the literature were used to determine measured or estimated values for the relevant distribution coefficients, which were in turn used to calculate retardation factors for a representative porous medium. Adsorption at the air-water interface was shown to be a primary source of retention for PFOA and PFOS, contributing approximately 80% of total retardation. Adsorption to NAPL-water interfaces and absorption by bulk NAPL were also shown to be significant sources of retention for PFOS and PFOA. The latter process was the predominant source of retention for 8:2 FTOH, contributing 98% of total retardation. These results indicate that we may anticipate significant retention of PFASs by these additional processes. In such cases, retardation of PFASs in source areas may be significantly greater than what is typically estimated based on the standard assumption of solid-phase adsorption as the sole retention mechanism. This has significant ramifications for

  10. Pathways to URM Retention: IBP's Professional Development and Mentoring Activities

    NASA Astrophysics Data System (ADS)

    Johnson, A.; Williamson Whitney, V.; Ricciardi, L.; Detrick, L.; Siegfried, D.; Fauver, A.; Ithier-Guzman, W.; Thomas, S. H.; Valaitis, S.

    2013-05-01

    As a not for profit organization, the Institute for Broadening Participation (IBP) hosts a variety of initiatives designed to increase the retention of underrepresented minority (URM) students pursuing pathways in STEM. IBP also assists with formative program evaluation design and implementation to help strengthen URM recruitment and retention elements. Successful initiatives include virtual and face-to-face components that bring together URM students with established URM and other scientists in academia, government and industry. These connections provide URMs with mentoring, networking opportunities, and professional skill development contributing to an improved retention rate of URM students. IBP's initiatives include the NASA One Stop Shopping Initiative (NASA OSSI), Pathways to Ocean Science and Engineering, and the Minorities Striving and Pursuing Higher Degrees of Success (MS PHD'S) in Earth System Science (ESS) Professional Development Program. The NASA OSSI recruits and facilitates student engagement in NASA education and employment opportunities. Pathways to Ocean Science connects and supports URM students with Ocean Science REU programs and serves as a resource for REU program directors. Pathways to Engineering has synthesized mentoring resources into an online mentoring manual for URM students that has been extensively vetted by mentoring experts throughout the country. The mentoring manual, which is organized by roles, provides undergraduates, graduates, postdocs, faculty and project directors with valuable resources. MS PHD'S, one of IBP's longest running and most successful initiatives, focuses on increasing the retention rate of URM students receiving advanced degrees in ESS. The program addresses barriers to retention in ESS including isolation, lack of preparation and professional development, and lack of mentoring. Program activities center on peer-to-peer community building, professional development exercises, networking experiences, one

  11. Biofilm roughness determines Cryptosporidium parvum retention in environmental biofilms.

    PubMed

    DiCesare, E A Wolyniak; Hargreaves, B R; Jellison, K L

    2012-06-01

    The genus Cryptosporidium is a group of waterborne protozoan parasites that have been implicated in significant outbreaks of gastrointestinal infections throughout the world. Biofilms trap these pathogens and can contaminate water supplies through subsequent release. Biofilm microbial assemblages were collected seasonally from three streams in eastern Pennsylvania and used to grow biofilms in laboratory microcosms. Daily oocyst counts in the influx and efflux flow allowed the calculation of daily oocyst retention in the biofilm. Following the removal of oocysts from the influx water, oocyst attachment to the biofilm declined to an equilibrium state within 5 days that was sustained for at least 25 days. Varying the oocyst loading rate for the system showed that biofilm retention could be saturated, suggesting that discrete binding sites determined the maximum number of oocysts retained. Oocyst retention varied seasonally but was consistent across all three sites; however, seasonal oocyst retention was not consistent across years at the same site. No correlation between oocyst attachment and any measured water quality parameter was found. However, oocyst retention was strongly correlated with biofilm surface roughness and roughness varied among seasons and across years. We hypothesize that biofilm roughness and oocyst retention are dependent on environmentally driven changes in the biofilm community rather than directly on water quality conditions. It is important to understand oocyst transport dynamics to reduce risks of human infection. Better understanding of factors controlling biofilm retention of oocysts should improve our understanding of oocyst transport at different scales.

  12. Affairs of State and Student Retention: An Exploratory Study of the Factors that Impact Student Retention in a Politically Turbulent Region

    ERIC Educational Resources Information Center

    Ben-Tsur, Dalia

    2007-01-01

    This study examines the impact of a country's security unrest on student retention. It draws on the key factors that influence retention worldwide, adopts Bourdieu's notion of cultural capital and also brings in concepts related to terrorism and security unrest traditionally absent from theories on student retention. Based on a case study carried…

  13. Cuff for Blood-Vessel Pressure Measurements

    NASA Technical Reports Server (NTRS)

    Shimizu, M.

    1982-01-01

    Pressure within blood vessel is measured by new cufflike device without penetration of vessel. Device continuously monitors blood pressure for up to 6 months or longer without harming vessel. Is especially useful for vessels smaller than 4 or 5 millimeters in diameter. Invasive methods damage vessel wall, disturb blood flow, and cause clotting. They do not always give reliable pressure measurements over prolonged periods.

  14. Neck-band retention for Canada geese in the Mississippi (USA) flyway

    USGS Publications Warehouse

    Samuel, M.D.; Weiss, N.T.; Rusch, D.H.; Craven, S.R.; Trost, R.E.; Caswell, F.D.

    1990-01-01

    We used capture, harvest, and observation histories of Canada geese (Branta canadensis) banded in the Mississippi flyway, 1974-88, to examine the problem of neck-band retention. Methods for the analysis of survival data were used to estimate rates of neck-band retention and to evaluate factors associated with neck-band loss. Sex, age of bird at banding, rivet use, and neck-band type significantly influenced neck-band retention. For most of the resulting cohorts (e.g., sex, age, rivet, and neck-band type categories), neck-band retention rates decreased through time. We caution against using small samples or data collected during short-term studies to determine retention rates. We suggest that observation data be used in neck-band retention studies to increase the efficiency of estimating retention time.

  15. Retention in Collegiate Aviation

    DOT National Transportation Integrated Search

    1996-01-01

    Retention issues are important to people in all aspects of business and academia. The relationship of how many people start a project and how many actually complete it is an important one, regardless whether the project is an academic degree or a bus...

  16. Carbon fiber internal pressure vessels

    NASA Technical Reports Server (NTRS)

    Simon, R. A.

    1973-01-01

    Internal pressure vessels were designed; the filament was wound of carbon fibers and epoxy resin and tested to burst. The fibers used were Thornel 400, Thornel 75, and Hercules HTS. Additional vessels with type A fiber were made. Polymeric linears were used, and all burst testing was done at room temperature. The objective was to produce vessels with the highest attainable PbV/W efficiencies. The type A vessels showed the highest average efficiency: 2.56 x 10 to the 6th power cm. Next highest efficiency was with Thornel 400 vessels: 2.21 x 10 to the 6th power cm. These values compare favorably with efficiency values from good quality S-glass vessels, but strains averaged 0.97% or less, which is less than 1/3 the strain of S-glass vessels.

  17. The Role of Student Characteristics in Predicting Retention in Online Courses

    ERIC Educational Resources Information Center

    Cochran, Justin D.; Campbell, Stacy M.; Baker, Hope M.; Leeds, Elke M.

    2014-01-01

    Given the continued issue of student retention for online classes, past research has suggested several "retention strategies" focused on engaging students as a way to reduce their withdrawal rate from these classes. However, a recent study testing the effects of these strategies on retention in online undergraduate business courses…

  18. Student Retention in Higher Education: Some Conceptual and Programmatic Perspectives.

    ERIC Educational Resources Information Center

    Lang, Marvel

    2002-01-01

    Provides a review of conceptual perspectives on the salient issues affecting student retention in higher education generally, and minority student retention in particular, over the past few decades. Also summarizes programmatic strategies implemented at institutions as examples of student retention initiatives that have had significant impacts.…

  19. The Relationship between High School Math Courses, High School GPA, and Retention of Honors Scholarships

    ERIC Educational Resources Information Center

    Megert, Diann Ackerman

    2005-01-01

    This research examined the high school transcripts of honors scholarship recipients to identify a better criterion for awarding scholarships than high school grade point average (GPA) alone. Specifically, this study compared the honors scholarship retention rate when the scholarship was awarded based on completed advanced high school math classes…

  20. Flexible Composite-Material Pressure Vessel

    NASA Technical Reports Server (NTRS)

    Brown, Glen; Haggard, Roy; Harris, Paul A.

    2003-01-01

    A proposed lightweight pressure vessel would be made of a composite of high-tenacity continuous fibers and a flexible matrix material. The flexibility of this pressure vessel would render it (1) compactly stowable for transport and (2) more able to withstand impacts, relative to lightweight pressure vessels made of rigid composite materials. The vessel would be designed as a structural shell wherein the fibers would be predominantly bias-oriented, the orientations being optimized to make the fibers bear the tensile loads in the structure. Such efficient use of tension-bearing fibers would minimize or eliminate the need for stitching and fill (weft) fibers for strength. The vessel could be fabricated by techniques adapted from filament winding of prior composite-material vessels, perhaps in conjunction with the use of dry film adhesives. In addition to the high-bias main-body substructure described above, the vessel would include a low-bias end substructure to complete coverage and react peak loads. Axial elements would be overlaid to contain damage and to control fiber orientation around side openings. Fiber ring structures would be used as interfaces for connection to ancillary hardware.

  1. 19 CFR 4.32 - Vessels in distress; landing of cargo.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Vessels in distress; landing of cargo. 4.32...; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Landing and Delivery of Cargo § 4.32 Vessels in distress; landing of cargo. (a) When a vessel from a foreign port arrives in distress at a port...

  2. Measuring Retention in HIV Care: The Elusive Gold Standard

    PubMed Central

    Mugavero, Michael J.; Westfall, Andrew O.; Zinski, Anne; Davila, Jessica; Drainoni, Mari-Lynn; Gardner, Lytt I.; Keruly, Jeanne C.; Malitz, Faye; Marks, Gary; Metsch, Lisa; Wilson, Tracey E.; Giordano, Thomas P.

    2012-01-01

    Background Measuring retention in HIV primary care is complex as care includes multiple visits scheduled at varying intervals over time. We evaluated six commonly used retention measures in predicting viral load (VL) suppression and the correlation among measures. Methods Clinic-wide patient-level data from six academic HIV clinics were used for 12-months preceding implementation of the CDC/HRSA Retention in Care intervention. Six retention measures were calculated for each patient based upon scheduled primary HIV provider visits: count and dichotomous missed visits, visit adherence, 6-month gap, 4-month visit constancy, and the HRSA HAB retention measure. Spearman correlation coefficients and separate unadjusted logistic regression models compared retention measures to one another and with 12-month VL suppression, respectively. The discriminatory capacity of each measure was assessed with the c-statistic. Results Among 10,053 patients, 8,235 (82%) had 12-month VL measures, with 6,304 (77%) achieving suppression (VL<400 c/mL). All six retention measures were significantly associated (P<0.0001) with VL suppression (OR;95%CI, c-statistic): missed visit count (0.73;0.71–0.75,0.67), missed visit dichotomous (3.2;2.8–3.6,0.62), visit adherence (3.9;3.5–4.3,0.69), gap (3.0;2.6–3.3,0.61), visit constancy (2.8;2.5–3.0,0.63), HRSA HAB (3.8;3.3–4.4,0.59). Measures incorporating “no show” visits were highly correlated (Spearman coefficient=0.83–0.85), as were measures based solely upon kept visits (Spearman coefficient=0.72–0.77). Correlation coefficients were lower across these two groups of measures (Range=0.16–0.57). Conclusions Six retention measures displayed a wide range of correlation with one another, yet each measure had significant association and modest discrimination for VL suppression. These data suggest there is no clear gold standard, and that selection of a retention measure may be tailored to context. PMID:23011397

  3. Psychological determinants of job retention in multiple sclerosis.

    PubMed

    Ford, Helen L; Wicks, Charlotte R; Stroud, Amanda; Tennant, Alan

    2018-01-01

    Maintaining paid work is a key issue for people with multiple sclerosis (PwMS). Different factors, including psychological attributes, can influence job retention. Understanding their role should inform potential interventions to help PwMS retain employment. The aim of this study was to identify the key factors which improve job retention in an employed cohort of PwMS. This three-year longitudinal study used validated self-completed measures of physical and psychological factors at four time points over 28 months. Of 208 employed PwMS, just over 1 in 10 was no longer working at the end of the study. Three variables were predictive of continuing employment; low 'work instability' at baseline increased the odds of job retention by a factor of 12.76; high levels of self-efficacy by a factor of 4.66 and being less than 50 years of age increased the odds of job retention by a factor of 3.90. Path analysis demonstrated the mediating role of self-efficacy between the physical impact of MS and the level of work instability at exit. Screening for work instability and self-efficacy in a clinical setting followed by appropriate interventions to increase self-efficacy and reduce work instability could aid job retention in MS.

  4. Distribution of normal superficial ocular vessels in digital images.

    PubMed

    Banaee, Touka; Ehsaei, Asieh; Pourreza, Hamidreza; Khajedaluee, Mohammad; Abrishami, Mojtaba; Basiri, Mohsen; Daneshvar Kakhki, Ramin; Pourreza, Reza

    2014-02-01

    To investigate the distribution of different-sized vessels in the digital images of the ocular surface, an endeavor which may provide useful information for future studies. This study included 295 healthy individuals. From each participant, four digital photographs of the superior and inferior conjunctivae of both eyes, with a fixed succession of photography (right upper, right lower, left upper, left lower), were taken with a slit lamp mounted camera. Photographs were then analyzed by a previously described algorithm for vessel detection in the digital images. The area (of the image) occupied by vessels (AOV) of different sizes was measured. Height, weight, fasting blood sugar (FBS) and hemoglobin levels were also measured and the relationship between these parameters and the AOV was investigated. These findings indicated a statistically significant difference in the distribution of the AOV among the four conjunctival areas. No significant correlations were noted between the AOV of each conjunctival area and the different demographic and biometric factors. Medium-sized vessels were the most abundant vessels in the photographs of the four investigated conjunctival areas. The AOV of the different sizes of vessels follows a normal distribution curve in the four areas of the conjunctiva. The distribution of the vessels in successive photographs changes in a specific manner, with the mean AOV becoming larger as the photos were taken from the right upper to the left lower area. The AOV of vessel sizes has a normal distribution curve and medium-sized vessels occupy the largest area of the photograph. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  5. Smooth muscle cell biglycan overexpression results in increased lipoprotein retention on extracellular matrix: implications for the retention of lipoproteins in atherosclerosis.

    PubMed

    O'Brien, Kevin D; Lewis, Katherine; Fischer, Jens W; Johnson, Pamela; Hwang, Jin-Yong; Knopp, Eleanor A; Kinsella, Michael G; Barrett, P Hugh R; Chait, Alan; Wight, Thomas N

    2004-11-01

    Lipoprotein retention on extracellular matrix (ECM) may play a central role in atherogenesis, and a specific extracellular matrix proteoglycan, biglycan, has been implicated in lipoprotein retention in human atherosclerosis. To test whether increased cellular biglycan expression results in increased retention of lipoproteins on ECM, rat aortic smooth muscle cells (SMCs) were transduced with a human biglycan cDNA-containing retroviral vector (LBSN) or with an empty retroviral vector (LXSN). To assess the importance of biglycan's glycosaminoglycan side chains in lipoprotein retention, ECM binding studies were also performed using RASMCs transduced with a retroviral vector encoding for a mutant, glycosaminoglycan-deficient biglycan (LBmutSN). Human biglycan mRNA and protein were confirmed in LBSN and LBmutSN RASMCs by Northern and Western blot analyses. HDL3+E binding to SMC ECM was increased significantly (as determined by 95% confidence intervals for binding curves) for LBSN as compared to either LXSN or LBmutSN cells; the increases for LBSN cell ECM were due primarily to an approximately 50% increase in binding sites (increased Bmax) versus LXSN cell ECM and of approximately 25% versus LBmutSN cell ECM. These results are consistent with the hypothesis that biglycan, through its glycosaminoglycan side chains, may mediate lipoprotein retention on atherosclerotic plaque ECM.

  6. Factors affecting retention of early pregnancy in dairy cattle.

    PubMed

    Starbuck, Melanie J; Dailey, Robert A; Inskeep, E Keith

    2004-08-01

    Potential factors affecting retention of pregnancy during weeks 5-9 of gestation were studied in dairy cows and heifers (N = 211) on two farms. Cows were examined by ultrasonography for presence of a viable embryo, and sizes of the corpus luteum (CL) and of follicles > or = 5mm were recorded. Blood samples were taken at each examination and assayed for progesterone and estradiol. Overall pregnancy loss was 11.4%. Cows with two CL did not have greater concentrations of progesterone than cows with one CL and they retained fewer pregnancies (P < 0.01; 73% versus 91%). Pregnancy retention was associated positively with concentrations of progesterone and estradiol during week 5 (P < 0.05). Embryos that were lost apparently died before CL regression. Retention of pregnancy declined in cows with high body condition and as age of the cow increased. Pregnancy retention was lower in cows bred to one of four frequently-used service sires (P < 0.05). Days postpartum, milk production, parity, service number, inseminator, synchronization of estrus, diameter of follicles and size of CL did not affect pregnancy retention. In conclusion, retention of pregnancy during placentation varied with concentrations of progesterone and estradiol, age of cow, body condition and service sire.

  7. Automatic detection of lung vessel bifurcation in thoracic CT images

    NASA Astrophysics Data System (ADS)

    Maduskar, Pragnya; Vikal, Siddharth; Devarakota, Pandu

    2011-03-01

    Computer-aided diagnosis (CAD) systems for detection of lung nodules have been an active topic of research for last few years. It is desirable that a CAD system should generate very low false positives (FPs) while maintaining high sensitivity. This work aims to reduce the number of false positives occurring at vessel bifurcation point. FPs occur quite frequently on vessel branching point due to its shape which can appear locally spherical due to the intrinsic geometry of intersecting tubular vessel structures combined with partial volume effects and soft tissue attenuation appearance surrounded by parenchyma. We propose a model-based technique for detection of vessel branching points using skeletonization, followed by branch-point analysis. First we perform vessel structure enhancement using a multi-scale Hessian filter to accurately segment tubular structures of various sizes followed by thresholding to get binary vessel structure segmentation [6]. A modified Reebgraph [7] is applied next to extract the critical points of structure and these are joined by a nearest neighbor criterion to obtain complete skeletal model of vessel structure. Finally, the skeletal model is traversed to identify branch points, and extract metrics including individual branch length, number of branches and angle between various branches. Results on 80 sub-volumes consisting of 60 actual vessel-branching and 20 solitary solid nodules show that the algorithm identified correctly vessel branching points for 57 sub-volumes (95% sensitivity) and misclassified 2 nodules as vessel branch. Thus, this technique has potential in explicit identification of vessel branching points for general vessel analysis, and could be useful in false positive reduction in a lung CAD system.

  8. Graphite filament wound pressure vessels

    NASA Technical Reports Server (NTRS)

    Feldman, A.; Damico, J. J.

    1972-01-01

    Filament wound NOL rings, 4-inch and 8-inch diameter closed-end vessels involving three epoxy resin systems and three graphite fibers were tested to develop property data and fabrication technology for filament wound graphite/epoxy pressure vessels. Vessels were subjected to single-cycle burst tests at room temperature. Manufacturing parameters were established for tooling, winding, and curing that resulted in the development of a pressure/vessel performance factor (pressure x volume/weight) or more than 900,000 in. for an oblate spheroid specimen.

  9. Vessel Loading Observations

    DOT National Transportation Integrated Search

    1999-01-01

    Vessel Loading Observations Procedures for P.L. 480, Titles II & III, : Section 416(b) and Food for Progress programs. Notice advises steamship lines and other interested parties that the vessel loading observation (VLO) procedure will continue to be...

  10. Individuals and Institutions : How to Advance Women in Science

    NASA Astrophysics Data System (ADS)

    Valian, Virginia

    2015-01-01

    The inception of the NSF ADVANCE program marked a change in NSF's efforts to improve the advancement of women in the sciences. Previous efforts had focused on providing women with funding to pursue their research. ADVANCE focuses on changing the institutions in which women do their research. Evidence of ADVANCE's successes can be seen both in the careers of individual women and in hiring and retention figures at the institutions that received funding. In Part 1, I will review interventions that help women to succeed, with a focus on the Sponsorship Program and the Workshop Series for Junior Faculty that the Gender Equity Project at Hunter College developed. In Part 2, I will review successes in changing hiring practices, with a focus on ADVANCE programs from the University of Michigan and the University of Wisconsin. In Part 3, I will analyze the costs and benefits of the two types of intervention, including the long time course of institutional change, the helpful or hurtful role that leaders can play, the need for intervention at the departmental level, and the potential for individuals to change institutions.

  11. Emotional intelligence, performance, and retention in clinical staff nurses.

    PubMed

    Codier, Estelle; Kamikawa, Cindy; Kooker, Barbara M; Shoultz, Jan

    2009-01-01

    Emotional intelligence has been correlated with performance, retention, and organizational commitment in professions other than nursing. A 2006 pilot study provided the first evidence of a correlation between emotional intelligence and performance in clinical staff nurses. A follow-up study was completed, the purpose of which was to explore emotional intelligence, performance level, organizational commitment, and retention. A convenience sample of 350 nurses in a large medical center in urban Hawaii participated in this study. This article reports the findings pertaining to the subset of 193 clinical staff nurses who responded. The Mayer-Salovey-Caruso Emotional Intelligence Test instrument was used to measure emotional intelligence abilities. Performance was defined as ranking on a clinical ladder. Commitment was scored on a Likert scale. The following variables measured retention: total years in nursing, years in current job, total years anticipated in current job, and total anticipated career length. Emotional intelligence scores in clinical staff nurses correlated positively with both performance level and retention variables. Clinical staff nurses with higher emotional intelligence scores demonstrated higher performance, had longer careers, and greater job retention.

  12. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  13. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  14. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  15. 33 CFR 157.15 - Slop tanks in tank vessels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Slop tanks in tank vessels. 157... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Design, Equipment, and Installation § 157.15 Slop tanks in tank vessels. (a) Number. A...

  16. 46 CFR 188.05-3 - New vessels and existing vessels for the purpose of application of regulations in this subchapter.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false New vessels and existing vessels for the purpose of application of regulations in this subchapter. 188.05-3 Section 188.05-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-3 New...

  17. 46 CFR 188.05-3 - New vessels and existing vessels for the purpose of application of regulations in this subchapter.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false New vessels and existing vessels for the purpose of application of regulations in this subchapter. 188.05-3 Section 188.05-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-3 New...

  18. 46 CFR 188.05-3 - New vessels and existing vessels for the purpose of application of regulations in this subchapter.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false New vessels and existing vessels for the purpose of application of regulations in this subchapter. 188.05-3 Section 188.05-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-3 New...

  19. 46 CFR 188.05-3 - New vessels and existing vessels for the purpose of application of regulations in this subchapter.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false New vessels and existing vessels for the purpose of application of regulations in this subchapter. 188.05-3 Section 188.05-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-3 New...

  20. 46 CFR 188.05-3 - New vessels and existing vessels for the purpose of application of regulations in this subchapter.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false New vessels and existing vessels for the purpose of application of regulations in this subchapter. 188.05-3 Section 188.05-3 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Application § 188.05-3 New...

  1. Meeting Students Where They Are: Advancing a Theory and Practice of Archives in the Classroom

    ERIC Educational Resources Information Center

    Saidy, Christina; Hannah, Mark; Sura, Tom

    2011-01-01

    This article uses theories of technical communication and archives to advance a pedagogy that includes archival production in the technical communication classroom. By developing and maintaining local classroom archives, students directly engage in valuable processes of appraisal, selection, collaboration, and retention. The anticipated outcomes…

  2. Clay Corner: Recreating Chinese Bronze Vessels.

    ERIC Educational Resources Information Center

    Gamble, Harriet

    1998-01-01

    Presents a lesson where students make faux Chinese bronze vessels through slab or coil clay construction after they learn about the history, function, and design of these vessels. Utilizes a variety of glaze finishes in order to give the vessels an aged look. Gives detailed guidelines for creating the vessels. (CMK)

  3. Blood vessel adaptation to gravity in a semi-arboreal snake

    NASA Technical Reports Server (NTRS)

    Conklin, D. J.; Lillywhite, H. B.; Olson, K. R.; Ballard, R. E.; Hargens, A. R.

    1996-01-01

    The effects of vasoactive agonists on systemic blood vessels were examined with respect to anatomical location and gravity acclimation in the semi-arboreal snake, Elaphe Obsoleta. Major blood vessels were reactive to putative neurotransmitters, hormones or local factors in vessel specific patterns. Catecholamines, adenosine triphosphate, histamine and high potassium (80 mM) stimulated significantly greater tension per unit vessel mass in posterior than anterior arteries. Anterior vessels were significantly more sensitive to catecholamines than midbody and posterior vessels. Angiotensin II stimulated significantly greater tension in carotid artery than in midbody and posterior dorsal aorta. Arginine vasotocin strongly contracted the left and right aortic arches and anterior dorsal aorta. Veins were strongly contracted by catecholamines, high potassium and angiotensin II, but less so by adenosine triphosphate, arginine vasotocin and histamine. Precontracted vessel were relaxed by acetylcholine and sodium nitroprusside, but not by atrial natriuretic peptide or bradykinin. Chronic exposure of snakes to intermittent hypergravity stress ( + 1.5 Gz at tail) did not affect the majority of vessel responses. These data demonstrate that in vitro tension correlates with that catecholamines, as well as other agonists, are important in mediating vascular responses to gravitational stresses in snakes.

  4. Superior long term outcome associated with native vessel versus graft vessel PCI following secondary PCI in patients with prior CABG.

    PubMed

    Mavroudis, Chrysostomos A; Kotecha, Tushar; Chehab, Omar; Hudson, Jonathan; Rakhit, Roby D

    2017-02-01

    Secondary percutaneous coronary intervention (PCI) in patients with prior coronary artery bypass graft surgery is increasingly common. Graft vessel PCI has higher rates of adverse events compared with native coronary vessel PCI. To investigate the clinical outcomes of patients with prior CABG who underwent secondary PCI of either a graft vessel (GV), a native coronary vessel (NV) or both graft and native (NG) vessels. 220 patients (84% male) who underwent PCI in our institution to either GV (n=89), NV (n=103) or both GV and NV (NG group) (n=28) were studied. The study population underwent 378 procedures (GV group; n=126, NV group; n=164 and NG group; n=88). Median follow up was for 36months [range 2-75months]. Target vessel revascularisation (TVR) occurred in 12.5% of the GV group and 3.6% in the NV group [p=0.0004], and was predominantly due to in-stent restenosis. Patients who had PCI due to TVR were more likely to suffer from diabetes and peripheral vascular disease. History of chronic renal failure was associated with higher risk (HR 2.21, p=0.005) whereas preserved left ventricular ejection fraction (LVEF) with lower risk (HR 0.17, p=0.0007) of death. The median survival (interval between CABG and end of follow-up period) was lower in the GV compared with the NV group (315 vs 372months p=0.005). This registry demonstrates inferior long term outcome for patients undergoing secondary PCI of GV versus NV. Where possible, a strategy of NV rather than GV target PCI should be considered in patients with prior CABG. Secondary PCI in patients with prior CABG surgery is increasingly common. Graft vessel PCI has inferior outcomes with high rates of restenosis and occlusion compared with native coronary vessel PCI. We studied the clinical outcomes of 220 patients with prior CABG who underwent secondary PCI to either a graft vessel (GV), a native coronary vessel (NV) or both graft and native (NG) vessels. Target vessel revascularisation was 5 times higher in the GV

  5. Small vessel hematocrit in ischemic myocardium

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gumm, D.C.; Cooper, S.M.; Marcus, M.L.

    1986-03-01

    As blood enters the microvasculature of normally perfused myocardium, there is a progressive decrease in small vessel hematocrit (SV Hct) due to RBC streaming in smaller branching vessels and the Fahraeus-Lindqvist effect. We hypothesized that if the coronary collateral circulation was composed of very small vessels branching from large parent vessels, plasma streaming would result in a further decrease of SV Hct in ischemic myocardium. Six open chest anesthetized dogs were studied. Plasma was labelled with /sup 59/FeCl siderophilin and RBC's with /sup 99/mTc to estimate SV Hct from myocardial biopsies. The LAD was occluded and cannulated for measurement ofmore » retrograde flow (arising presumably from proximal collaterals). The ischemic region was identified using the microsphere shadow technique. Collateral flow after LAD occlusion was 30 +- 12 ml/min 100g (x +- SE). Systemic Hct was 40 +- 1%. The Hct of blood from retrograde flow was 39 +- 1% (p = NS). Activity of /sup 59/FeCl and /sup 99/mTc in known quantities of blood were compared to myocardial biopsies to estimate SV Hct. Ischemic SV Hct was 23 +- 2% and non-ischemic SV Hct was 21 +- 1% (p = NS). We conclude that the size and branching pattern of coronary collaterals is such that plasma streaming in collaterals does not result in an additional decrease in SV Hct in ischemic myocardium.« less

  6. Blood Vessel Tension Tester

    NASA Technical Reports Server (NTRS)

    1978-01-01

    In the photo, a medical researcher is using a specially designed laboratory apparatus for measuring blood vessel tension. It was designed by Langley Research Center as a service to researchers of Norfolk General Hospital and Eastern Virginia Medical School, Norfolk, Virginia. The investigators are studying how vascular smooth muscle-muscle in the walls of blood vessels-reacts to various stimulants, such as coffee, tea, alcohol or drugs. They sought help from Langley Research Center in devising a method of measuring the tension in blood vessel segments subjected to various stimuli. The task was complicated by the extremely small size of the specimens to be tested, blood vessel "loops" resembling small rubber bands, some only half a millimeter in diameter. Langley's Instrumentation Development Section responded with a miniaturized system whose key components are a "micropositioner" for stretching a length of blood vessel and a strain gage for measuring the smooth muscle tension developed. The micropositioner is a two-pronged holder. The loop of Mood vessel is hooked over the prongs and it is stretched by increasing the distance between the prongs in minute increments, fractions of a millimeter. At each increase, the tension developed is carefully measured. In some experiments, the holder and specimen are lowered into the test tubes shown, which contain a saline solution simulating body fluid; the effect of the compound on developed tension is then measured. The device has functioned well and the investigators say it has saved several months research time.

  7. Exploring the role of advanced nurse practitioners in leadership.

    PubMed

    Anderson, Claire

    2018-05-02

    There have been several changes to healthcare services in the UK over recent years, with rising NHS costs and increasing demands on healthcare professionals to deliver high-quality care. Simultaneously, public inquiries have identified suboptimal leadership throughout the NHS, which has been linked to a lack of clear leadership across the healthcare professions. In nursing, the role of the advanced nurse practitioner is regarded as a solution to this leadership challenge. This article examines the background to the development of the advanced nurse practitioner role. It also explores the various factors that may affect nurse leadership and the role of the advanced nurse practitioner, including professional identity, gender, nursing's strategic influence, clinical outcomes, and recruitment and retention. The article concludes that while advanced nurse practitioners can positively influence clinical outcomes and cost efficiency, they must also be adequately prepared to undertake a leadership role. © 2018 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

  8. Blood Vessel Adaptation with Fluctuations in Capillary Flow Distribution

    PubMed Central

    Hu, Dan; Cai, David; Rangan, Aaditya V.

    2012-01-01

    Throughout the life of animals and human beings, blood vessel systems are continuously adapting their structures – the diameter of vessel lumina, the thickness of vessel walls, and the number of micro-vessels – to meet the changing metabolic demand of the tissue. The competition between an ever decreasing tendency of luminal diameters and an increasing stimulus from the wall shear stress plays a key role in the adaptation of luminal diameters. However, it has been shown in previous studies that the adaptation dynamics based only on these two effects is unstable. In this work, we propose a minimal adaptation model of vessel luminal diameters, in which we take into account the effects of metabolic flow regulation in addition to wall shear stresses and the decreasing tendency of luminal diameters. In particular, we study the role, in the adaptation process, of fluctuations in capillary flow distribution which is an important means of metabolic flow regulation. The fluctuation in the flow of a capillary group is idealized as a switch between two states, i.e., an open-state and a close-state. Using this model, we show that the adaptation of blood vessel system driven by wall shear stress can be efficiently stabilized when the open time ratio responds sensitively to capillary flows. As micro-vessel rarefaction is observed in our simulations with a uniformly decreased open time ratio of capillary flows, our results point to a possible origin of micro-vessel rarefaction, which is believed to induce hypertension. PMID:23029014

  9. Determining Factors in Student Retention in Online Courses

    ERIC Educational Resources Information Center

    Friðriksdóttir, Kolbrún; Arnbjörnsdóttir, Birna

    2017-01-01

    The rapid growth of online education courses, especially Massive Open Online Courses (MOOCs), has called attention to the issue of student retention and low overall completion rates (Gaebel, 2013). The impact of different modes of delivery on retention has also received attention with a blended learning mode being deemed most effective in…

  10. Disposal of Vessels at Sea

    EPA Pesticide Factsheets

    Vessel disposal general permits are issued by the EPA under the Marine Protection, Research and Sanctuaries Act. Information is provided for vessel disposal permit applicants and where to dispose a vessel.

  11. Investigation of the helium effects on deuterium retention in thin film lithium coatings on tungsten substrates

    NASA Astrophysics Data System (ADS)

    Neff, A. L.; Allain, J. P.; Morgan, T. W.

    2017-10-01

    In a burning fusion plasma, the materials on the walls of the plasma vessel will have a significant effect on the performance of the plasma. Any amount of high Z wall material that is eroded will contaminate and cool the plasma and may lead to a disruption. Additionally, if the material retains or reflects fuel it can affect the stability of the plasma. A high recycling wall that retains minimal fuel will allow better control of the fuel inventory, especially tritium, in the walls. In contrast, a low recycling wall leads to improved plasma performance by preventing instabilities in the plasma. We have observed that when 5% He is added to D ions during low flux (1017 m-2s-1) dual ion beam irradiation the amount of D retained in the Li film diminishes. This conclusion is based on the reduction of a XPS peak (at 533 eV) associated with D retention in Li films. To further investigate this phenomenon, we have continued the dual beam studies in IGNIS (Ion-Gas-Neutral Interactions with Surfaces) by varying the energy and concentration of He to D. Additionally, we exposed lithiated W to sequential D and He plasmas (1024 m-2s-1 flux) in Magnum PSI at DIFFER. With XPS, we analyzed the chemistry of the Li films and determined changes in retention. These results will be presented. Work supported by DOE contract DE-SC0010719.

  12. Endothelin ETA Receptor Blockade, by Activating ETB Receptors, Increases Vascular Permeability and Induces Exaggerated Fluid Retention.

    PubMed

    Vercauteren, Magali; Trensz, Frederic; Pasquali, Anne; Cattaneo, Christophe; Strasser, Daniel S; Hess, Patrick; Iglarz, Marc; Clozel, Martine

    2017-05-01

    Endothelin (ET) receptor antagonists have been associated with fluid retention. It has been suggested that, of the two endothelin receptor subtypes, ET B receptors should not be blocked, because of their involvement in natriuresis and diuresis. Surprisingly, clinical data suggest that ET A -selective antagonists pose a greater risk of fluid overload than dual antagonists. The purpose of this study was to evaluate the contribution of each endothelin receptor to fluid retention and vascular permeability in rats. Sitaxentan and ambrisentan as ET A -selective antagonists and bosentan and macitentan as dual antagonists were used as representatives of each class, respectively. ET A -selective antagonism caused a dose-dependent hematocrit/hemoglobin decrease that was prevented by ET B -selective receptor antagonism. ET A -selective antagonism led to a significant blood pressure reduction, plasma volume expansion, and a greater increase in vascular permeability than dual antagonism. Isolated vessel experiments showed that ET A -selective antagonism increased vascular permeability via ET B receptor overstimulation. Acutely, ET A -selective but not dual antagonism activated sympathetic activity and increased plasma arginine vasopressin and aldosterone concentrations. The hematocrit/hemoglobin decrease induced by ET A -selective antagonism was reduced in Brattleboro rats and in Wistar rats treated with an arginine vasopressin receptor antagonist. Finally, the decrease in hematocrit/hemoglobin was larger in the venous than in the arterial side, suggesting fluid redistribution. In conclusion, by activating ET B receptors, endothelin receptor antagonists (particularly ET A -selective antagonists) favor edema formation by causing: 1) fluid retention resulting from arginine vasopressin and aldosterone activation secondary to vasodilation, and 2) increased vascular permeability. Plasma volume redistribution may explain the clinical observation of a hematocrit/hemoglobin decrease

  13. Reading Authentic EFL Text Using Visualization and Advance Organizers in a Multimedia Learning Environment

    ERIC Educational Resources Information Center

    Lin, Huifen; Chen, Tsuiping

    2007-01-01

    The purpose of this experimental study was to compare the effects of different types of computer-generated visuals (static versus animated) and advance organizers (descriptive versus question) in enhancing comprehension and retention of a content-based lesson for learning English as a Foreign Language (EFL). Additionally, the study investigated…

  14. By Different Cellular Mechanisms, Lymphatic Vessels Sprout by Endothelial Cell Recruitment Whereas Blood Vessels Grow by Vascular Expansion

    NASA Technical Reports Server (NTRS)

    Parsons-Wingerter, Patricia; McKay, Terri L.; Leontiev, Dmitry; Condrich, Terence K.; DiCorleto, Paul E.

    2005-01-01

    The development of effective vascular therapies requires the understanding of all modes of vessel formation contributing to vasculogenesis, angiogenesis (here termed hemangiogenesis) and lymphangiogenesis. We show that lymphangiogenesis proceeds by blind-ended vessel sprouting via recruitment of isolated endothelial progenitor cells to the tips of growing vessels, whereas hemangiogenesis occurs by non-sprouting vessel expansion from the capillary network, during middevelopment in the quail chorioallantoic membrane (CAM). Blood vessels expanded out of capillaries that displayed transient expression of alpha smooth muscle actin (alphaSMA), accompanied by mural recruitment of migratory progenitor cells expressing SMA. Lymphatics and blood vessels were identified by confocal/fluorescence microscopy of vascular endothelial growth factor (VEGF) receptors VEGFR-1 and VEGFR-2, alphaSMA (expressed on CAM blood vessels but not on lymphatics), homeobox transcription factor Prox-1 (specific to CAM lymphatic endothelium), and the quail hematopoetic/vascular marker, QH-1. Expression of VEGFR-1 was highly restricted to blood vessels (primarily capillaries). VEGFR-2 was expressed intensely in isolated hematopoietic cells, lymphatic vessels and moderately in blood vessels. Prox-1 was absent from endothelial progenitor cells prior to lymphatic recruitment. Although vascular endothelial growth factor-165 (VEGF(sub 165)) is a key regulator of numerous cellular processes in hemangiogenesis and vasculogenesis, the role of VEGF(sub 165) in lymphangiogenesis is less clear. Exogenous VEGF(sub 165) increased blood vessel density without changing endogenous modes of vascular/lymphatic vessel formation or marker expression patterns. However, VEGF(sub 165) did increase the frequency of blood vascular anastomoses and strongly induced the antimaturational dissociation of lymphatics from blood vessels, with frequent formation of homogeneous lymphatic networks.

  15. Persistence-Retention. Snapshot™ Report, Spring 2014

    ERIC Educational Resources Information Center

    National Student Clearinghouse, 2014

    2014-01-01

    This snapshot report provides information on student persistence and retention rates for Spring 2014. Data is presented in tabular format on the following: (1) First-Year Persistence and Retention Rates by Starting Enrollment Intensity (all institutional sectors); (2) First-Year Persistence and Retention Rates by Age at College Entry (all…

  16. Peer Mentoring in Long-Term Care: Rational, Design, and Retention

    ERIC Educational Resources Information Center

    Hegeman, Carol; Hoskinson, Debi; Munro, Heather; Maiden, Patricia; Pillemer, Karl

    2007-01-01

    This article describes two successful peer-mentoring programs designed to improve the quality of care in nursing homes and retention rates among direct care staff. The first program, "Growing Strong Roots," examined CNA retention rates and the second program, "Peer Mentoring for Long Term Charge Nurses," examined RN and LPN retention rates. These…

  17. Retention of Homeless Smokers in the Power to Quit Study.

    PubMed

    Richards, Christina M; Sharif, Faduma; Eischen, Sara; Thomas, Janet; Wang, Qi; Guo, Hongfei; Luo, Xianghua; Okuyemi, Kolawole

    2015-09-01

    Concerns about retention are a major barrier to conducting studies enrolling homeless individuals. Since smoking is a major problem in homeless communities and research on effective methods of promoting smoking cessation is needed, we describe strategies used to increase retention and participant characteristics associated with retention in smoking cessation study enrolling homeless adults. The parent study was a 2-group randomized controlled trial with 26-week follow-up enrolling 430 homeless smokers from emergency shelters and transitional housing units in Minneapolis/Saint Paul, MN, USA. Multiple strategies were used to increase retention, including conducting visits at convenient locations for participants, collecting several forms of contact information from participants, using a schedule that was flexible and included frequent low-intensity visits, and providing incentives. Participant demographics as well as characteristics related to tobacco and drug use and health status were analyzed for associations with retention using univariate and multivariate analysis. Overall retention was 75% at 26 weeks. Factors associated with increased retention included greater age; having healthcare coverage; history of multiple homeless episodes, lower stress level; and higher PHQ-9 (Patient Health Questionnaire-9) score. A history of excessive drinking and drug use were associated with decreased retention. It is possible to successfully retain homeless individuals in a smoking cessation study if the study is designed with participants' needs in mind. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  18. Nurse retention and satisfaction in Ecuador: implications for nursing administration.

    PubMed

    Palmer, Sheri P

    2014-01-01

    This study explores the characteristics of professional nursing work environments that may affect nursing turnover and satisfaction within a large Ecuadorian hospital. Nursing turnover is a challenge and may compromise patient care. Work dissatisfaction contributes to high turnover. Improving nurse satisfaction can contribute to better patient outcomes. Eighty-eight nurses participated in a quantitative and qualitative survey focusing on nursing satisfaction, turnover and selected organisation characteristics. Issues that may affect nurse satisfaction and turnover were identified using questions from the Nursing Work Index: pay, insufficient number of nurses, undervaluing of nurses by public and the medical team, limited advancement opportunities, lack of autonomy and inflexibility in schedule. Other themes identified from qualitative data are reported. The top factor of decreased satisfaction was low pay as indicated by the Nursing Work Index. The qualitative results showed that low pay was the factor for nurse turnover. Additional factors related to nursing satisfaction can be addressed to improve nurse retention. Along with increasing nursing pay, strategies to consider in decreasing turnover and increasing satisfaction included: providing opportunities for nursing advancement, promoting the value of nursing, creating clinical protocols and enhancing autonomy. This study adds to knowledge about nursing needs and satisfaction in South America. © 2013 John Wiley & Sons Ltd.

  19. Retention capacity of correlated surfaces.

    PubMed

    Schrenk, K J; Araújo, N A M; Ziff, R M; Herrmann, H J

    2014-06-01

    We extend the water retention model [C. L. Knecht et al., Phys. Rev. Lett. 108, 045703 (2012)] to correlated random surfaces. We find that the retention capacity of discrete random landscapes is strongly affected by spatial correlations among the heights. This phenomenon is related to the emergence of power-law scaling in the lake volume distribution. We also solve the uncorrelated case exactly for a small lattice and present bounds on the retention of uncorrelated landscapes.

  20. Rotating Vessels for Growing Protein Crystals

    NASA Technical Reports Server (NTRS)

    Cottingham, Paul

    2005-01-01

    Rotating vessels have been proposed as means of growing larger, more nearly uniform protein crystals than would otherwise be possible in the presence of normal Earth gravitation. Heretofore, nonrotating vessels have been used. It is difficult to grow high-quality protein crystals in the terrestrial gravitational field because of convection plumes created by the interaction between gravitation and density gradients in protein-solution depletion layers around growing crystals. The density gradients and the associated convection plumes cause the surfaces of growing crystals to be exposed to nonuniform solution densities, thereby causing the crystals to form in irregular shapes. The microgravitational environment of outer space has been utilized to eliminate gravitation-induced convection, but this approach is generally not favorable because of the high cost and limited availability of space flight. The use of a rotating vessel according to the proposal is intended to ameliorate the effects of gravitation and the resultant convection, relative to the corresponding effects in a non-rotating vessel. The rotation would exert an averaging effect over time, distributing the convective force on the depletion layer. Therefore, the depletion layer would be more nearly uniform and, as a result, the growing crystal would be more nearly perfect. The proposal admits of variations (see figure), including the following: The growing crystal could be rotated about its own central axis or an external axis. The crystal-growth vessel could be of any of various shapes, including cylindrical, hemispherical, conical, and combinations thereof. The crystal-growth vessel could be suspended in a viscous fluid in an outer vessel to isolate the growing crystal from both ambient vibrations and vibrations induced by a mechanism that drives the rotation. The rotation could be coupled to the crystal-growth vessel by viscous or magnetic means. The crystal-growth vessel could be supported within the

  1. An update on the blood vessel in migraine.

    PubMed

    Brennan, K C; Charles, Andrew

    2010-06-01

    The cranial blood vessel is considered an integral player in the pathophysiology of migraine, but its perceived role has been subject to much discussion and controversy over the years. We will discuss the evolution in our scientific understanding of cranial blood vessels (primarily arteries) in migraine. Recent developments have clarified the role of cranial blood vessels in the trigemino-vascular system and in cortical spreading depression. An underlying theme is the intimate relation between vascular activity and neural function, and we will emphasize the various roles of the blood vessel that go beyond delivering blood. We conclude that migraine cannot be understood, either from a research or clinical point of view, without an understanding of the vascular derangements that accompany it. Migraine is accompanied by significant derangements in vascular function that may represent important targets for investigation and treatment.

  2. 46 CFR 126.225 - Alternate tonnage for offshore supply vessels seeking oil spill response vessel certification.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... oil spill response vessel certification. 126.225 Section 126.225 Shipping COAST GUARD, DEPARTMENT OF... Inspection § 126.225 Alternate tonnage for offshore supply vessels seeking oil spill response vessel... also be certificated as an oil spill response vessel. [76 FR 77131, Dec. 12, 2011] ...

  3. Forest representation of vessels in cone-beam computed tomographic angiography.

    PubMed

    Chen, Zikuan; Ning, Ruola

    2005-01-01

    Cone-beam computed tomographic angiography (CBCTA) provides a fast three-dimensional (3D) vascular imaging modality, aiming at digitally representing the spatial vascular structure in an angiographic volume. Due to the finite coverage of cone-beam scan, as well as the volume cropping in volumetric image processing, an angiographic volume may fail to contain a whole vascular tree, but rather consist of a multitude of vessel segments or subtrees. As such, it is convenient to represent multitudinal components by a forest. The vessel tracking issue then becomes component characterization/identification in the forest. The forest representation brings several conveniences for vessel tracking: (1) to sort and count the vessels in an angiographic volume, for example, according to spatial occupancy and skeleton pathlength; (2) to single out a vessel and perform in situ 3D measurement and 3D visualization in the support space; (3) to delineate individual vessels from the original angiographic volume; and (4) to cull the forest by getting rid of non-vessels and small vessels. A 3D skeletonization is used to generate component skeletons. For tree construction from skeletons, we suggest a pathlength-based procedure, which lifts the restrictions of unit-width skeleton and root determination. We experimentally demonstrate the forest representation of a dog's carotid arteries in a CBCTA system. In principle, the forest representation is useful for managing vessels in both 2D angiographic images and 3D angiographic volumes.

  4. "The nurse satisfaction, service quality and nurse retention chain": implications for management of recruitment and retention.

    PubMed

    Newman, Karin; Maylor, Uvanney; Chansarkar, Bal

    2002-01-01

    This paper presents the findings of a qualitative study, based on interviews with over 130 nurses and midwives in four London Trust hospitals on: the main factors influencing nurse satisfaction and retention; empirical support for the robustness of a conceptual framework or model "the nurse satisfaction, service quality and nurse retention chain"; and some managerial considerations for recruitment and retention. The three main factors influencing job satisfaction were patients, the inherent characteristics of nursing and the nursing team; the two main sources of job dissatisfaction were staff shortages and poor management and amongst nurse retention strategies improving working conditions was more important than increased pay. For recruitment, as well as retention, improving the image and reputation of nursing along with improvements in work-life balance were pre-requisites for meeting the challenging target of an additional 20,000 nurses on the wards by 2004.

  5. 50 CFR 300.32 - Vessel licenses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... South Pacific Tuna Fisheries § 300.32 Vessel licenses. (a) Each vessel fishing in the Licensing Area... amount, in metric tons, of any tuna species landed or transshipped from the vessel at United States ports...

  6. 50 CFR 300.32 - Vessel licenses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... South Pacific Tuna Fisheries § 300.32 Vessel licenses. (a) Each vessel fishing in the Licensing Area... amount, in metric tons, of any tuna species landed or transshipped from the vessel at United States ports...

  7. 50 CFR 300.32 - Vessel licenses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... South Pacific Tuna Fisheries § 300.32 Vessel licenses. (a) Each vessel fishing in the Licensing Area... amount, in metric tons, of any tuna species landed or transshipped from the vessel at United States ports...

  8. 50 CFR 300.32 - Vessel licenses.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... South Pacific Tuna Fisheries § 300.32 Vessel licenses. (a) Each vessel fishing in the Licensing Area... amount, in metric tons, of any tuna species landed or transshipped from the vessel at United States ports...

  9. Visualizing blood vessel trees in three dimensions: clinical applications

    NASA Astrophysics Data System (ADS)

    Bullitt, Elizabeth; Aylward, Stephen

    2005-04-01

    A connected network of blood vessels surrounds and permeates almost every organ of the human body. The ability to define detailed blood vessel trees enables a variety of clinical applications. This paper discusses four such applications and some of the visualization challenges inherent to each. Guidance of endovascular surgery: 3D vessel trees offer important information unavailable by traditional x-ray projection views. How best to combine the 2- and 3D image information is unknown. Planning/guidance of tumor surgery: During tumor resection it is critical to know which blood vessels can be interrupted safely and which cannot. Providing efficient, clear information to the surgeon together with measures of uncertainty in both segmentation and registration can be a complex problem. Vessel-based registration: Vessel-based registration allows pre-and intraoperative images to be registered rapidly. The approach both provides a potential solution to a difficult clinical dilemma and offers a variety of visualization opportunities. Diagnosis/staging of disease: Almost every disease affects blood vessel morphology. The statistical analysis of vessel shape may thus prove to be an important tool in the noninvasive analysis of disease. A plethora of information is available that must be presented meaningfully to the clinician. As medical image analysis methods increase in sophistication, an increasing amount of useful information of varying types will become available to the clinician. New methods must be developed to present a potentially bewildering amount of complex data to individuals who are often accustomed to viewing only tissue slices or flat projection views.

  10. Application of morphological bit planes in retinal blood vessel extraction.

    PubMed

    Fraz, M M; Basit, A; Barman, S A

    2013-04-01

    The appearance of the retinal blood vessels is an important diagnostic indicator of various clinical disorders of the eye and the body. Retinal blood vessels have been shown to provide evidence in terms of change in diameter, branching angles, or tortuosity, as a result of ophthalmic disease. This paper reports the development for an automated method for segmentation of blood vessels in retinal images. A unique combination of methods for retinal blood vessel skeleton detection and multidirectional morphological bit plane slicing is presented to extract the blood vessels from the color retinal images. The skeleton of main vessels is extracted by the application of directional differential operators and then evaluation of combination of derivative signs and average derivative values. Mathematical morphology has been materialized as a proficient technique for quantifying the retinal vasculature in ocular fundus images. A multidirectional top-hat operator with rotating structuring elements is used to emphasize the vessels in a particular direction, and information is extracted using bit plane slicing. An iterative region growing method is applied to integrate the main skeleton and the images resulting from bit plane slicing of vessel direction-dependent morphological filters. The approach is tested on two publicly available databases DRIVE and STARE. Average accuracy achieved by the proposed method is 0.9423 for both the databases with significant values of sensitivity and specificity also; the algorithm outperforms the second human observer in terms of precision of segmented vessel tree.

  11. Hydrodynamic boost: a novel re-entry technique in subintimal angioplasty of below-the-knee vessels.

    PubMed

    Ferraresi, Roberto; Hamade, Meneme; Gallicchio, Vito; Troisi, Nicola; Mauri, Giovanni

    2016-08-01

    To describe the hydrodynamic boost (HB) technique and report our preliminary results with this technique in the subintimal angioplasty of below-the-knee vessels. HB was used in 23 cases (14 males, mean age 73 ± 12 years) of critical limb ischemia, with long chronic total occlusion of tibial arteries extended to the ankle level. The operator performs a manual injection of diluted contrast dye through a 4 F catheter into the subintimal space, close to the patent true distal lumen, in order to achieve a tear in the intimal flap and a connection with the true lumen. In 19/23 (83 %) cases, the HB was effective in creating a connection between the subintimal space and the true distal lumen and it was possible to advance a wire and to conclude the procedure. In 4/23 (17 %) lesions, the HB failed and the procedure was successfully completed by retrograde approach. No major complications occurred. Mean length between catheter tip and re-entry point was 8 ± 5 mm. HB seems to be a feasible, safe and effective re-entry technique in distal below-the-knee vessels. This method represents an easy option for re-entry that extends the possibility of antegrade approach to obtain a successful revascularization. • In subintimal angioplasty of below-the-knee vessel re-entry can represent a challenge. • Inability to re-enter may determine the failure of the revascularization procedure. • HB is a novel re-entry technique feasible in distal below-the-knee vessels. • HB may increase the success rate of antegrade approach. • In case of failure, retrograde approach remains feasible.

  12. [S1 Herpes zoster localization: acute urinary retention in woman].

    PubMed

    Vella, Marco; Mastrocinque, Giuseppe; Romeo, Salvatore; Giammanco, Giovanni; Melloni, Darwin

    2011-01-01

    Acute urinary retention in women is rare. The varicella-zoster virus causes inflammatory lesions of the sensory-root ganglions, meninges and, less frequently, spinal cord. Herpes zoster has been reported to affect, although rarely, lower urinary tract innervations, and acute urinary retention can be thought to occur in the presence of sacral dermatome involvement. Usually it is located in S2-4 dermatome and the prognosis for acute urinary retention is benign resolving in about 20 days. We present a case in which the S1 dermatome was involved and acute urinary retention developed. After 10 days of specific therapy and self-catheterization the problem resolved.

  13. 12 CFR 202.12 - Record retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 2 2010-01-01 2010-01-01 false Record retention. 202.12 Section 202.12 Banks... OPPORTUNITY ACT (REGULATION B) § 202.12 Record retention. (a) Retention of prohibited information. A creditor...) Applications. For 25 months (12 months for business credit, except as provided in paragraph (b)(5) of this...

  14. Predictors of home healthcare nurse retention.

    PubMed

    Ellenbecker, Carol Hall; Porell, Frank W; Samia, Linda; Byleckie, James J; Milburn, Michael

    2008-01-01

    To examine the level of job satisfaction and test a theoretical model of the direct and indirect effects of job satisfaction, and individual nurse and agency characteristics, on intent to stay and retention for home healthcare nurses. A descriptive correlation study of home healthcare nurses in six New England states. Home healthcare nurse job satisfaction self-report data was collected with the HHNJS survey questionnaire & Retention Survey Questionnaire. Based on a structural equation model, job tenure and job satisfaction were the strongest predictors of nurse retention. Understanding the variables associated with home healthcare nurse retention can help agencies retain nurses in a time of severe nurse shortages and increased patient demand. Predicted nursing shortages and increasing demand have made the retention of experienced, qualified nursing staff essential to assure access to high-quality home healthcare services in the future.

  15. Retention of minority participants in clinical research studies.

    PubMed

    Keller, Colleen S; Gonzales, Adelita; Fleuriet, K Jill

    2005-04-01

    Recruitment of minority participants for clinical research studies has been the topic of several analytical works. Yet retention of participants, most notably minority and underserved populations, is less reported and understood, even though these populations have elevated health risks. This article describes two related, intervention-based formative research projects in which researchers used treatment theory to address issues of recruitment and retention of minority women participants in an exercise program to reduce obesity. Treatment theory incorporates a model of health promotion that allows investigators to identify and control sources of extraneous variables. The authors' research demonstrates that treatment theory can improve retention of minority women participants by considering critical inputs, mediating processes, and substantive participant characteristics in intervention design.

  16. Maximizing retention with high risk participants in a clinical trial.

    PubMed

    Kim, Romina; Hickman, Norval; Gali, Kathleen; Orozco, Nicholas; Prochaska, Judith J

    2014-01-01

    To describe effective retention strategies in a clinical trial with a high risk, low-income, and vulnerable patient population with serious mental illness. Follow-up assessments were conducted for a randomized clinical tobacco treatment trial at 3, 6, and 12 months postbaseline. Initial follow-up rates of <40% at 3 months led to implementation of proactive retention strategies including obtaining extensive contact information; building relationships with case managers and social workers; contacting jails and prisons; text messaging, e-mailing, and messaging via social networking sites; identifying appointments via electronic medical record; and field outreach to treatment facilities, residences, and parks. Large urban public hospital. Participants were current smokers recruited from 100% smoke-free locked psychiatry units. Assessments covered demographics, substance use, and mental health functioning. Retention rates were plotted over time in relation to key retention strategies. Chi-square and t-tests were used to examine participant predictors of retention at each follow-up. At the 12-month follow-up, the retention strategies that most frequently led to assessment completion were identified. The sample (N = 100) was 65% male; age x = 39.5 years (SD = 11.3); 44% non-Hispanic white; 46% on Medicaid and 34% uninsured; 79% unemployed; and 48% unstably housed. Proactive retention strategies dramatically increased follow-up rates, concluding at 3 months = 82.65%, 6 months = 89.69%, and 12 months = 92.78%. Married and divorced/separated/widowed participants, those with higher income, and participants with alcohol or illicit drug problems had increased retention from 3- to 12-month follow-up. Follow-up rates improved as proactive methods to contact participants were implemented. Dedicated research staff, multiple methods, community networking, and outreach within drug treatment settings improved retention.

  17. Vacuum-isolation vessel and method for measurement of thermal noise in microphones

    NASA Technical Reports Server (NTRS)

    Zuckerwar, Allan J. (Inventor); Ngo, Kim Chi T. (Inventor)

    1992-01-01

    The vacuum isolation vessel and method in accordance with the present invention are used to accurately measure thermal noise in microphones. The apparatus and method could be used in a microphone calibration facility or any facility used for testing microphones. Thermal noise is measured to determine the minimum detectable sound pressure by the microphone. Conventional isolation apparatus and methods have been unable to provide an acoustically quiet and substantially vibration free environment for accurately measuring thermal noise. In the present invention, an isolation vessel assembly comprises a vacuum sealed outer vessel, a vacuum sealed inner vessel, and an interior suspension assembly coupled between the outer and inner vessels for suspending the inner vessel within the outer vessel. A noise measurement system records thermal noise data from the isolation vessel assembly. A vacuum system creates a vacuum between an internal surface of the outer vessel and an external surface of the inner vessel. The present invention thus provides an acoustically quiet environment due to the vacuum created between the inner and outer vessels and a substantially vibration free environment due to the suspension assembly suspending the inner vessel within the outer vessel. The thermal noise in the microphone, effectively isolated according to the invention, can be accurately measured.

  18. Donor retention in health care in Iran: a factor analysis

    PubMed Central

    Aghababa, Sara; Nasiripour, Amir Ashkan; Maleki, Mohammadreza; Gohari, Mahmoodreza

    2017-01-01

    Background: Long-term financial support is essential for the survival of a charitable organization. Health charities need to identify the effective factors influencing donor retention. Methods: In the present study, the items of a questionnaire were derived from both literature review and semi-structured interviews related to donor retention. Using a purposive sampling, 300 academic and executive practitioners were selected. After the follow- up, a total of 243 usable questionnaires were prepared for factor analysis. The questionnaire was validated based on the face and content validity and reliability through Cronbach’s α-coefficient. Results: The results of exploratory factor analysis extracted 2 factors for retention: donor factor (variance = 33.841%; Cronbach’s α-coefficient = 90.2) and charity factor (variance = 29.038%; Cronbach’s α-coefficient = 82.8), respectively. Subsequently, confirmatory factor analysis was applied to support the overall reasonable fit. Conclusions: In this study, it was found that repeated monetary donations are supplied to the charitable organizations when both aspects of donor factor (retention factor and charity factor) for retention are taken into consideration. This model could provide a perspective for making sustainable donations and charitable giving PMID:28955663

  19. Binding of 11C-Pittsburgh compound-B correlated with white matter injury in hypertensive small vessel disease.

    PubMed

    Hashimoto, Tetsuya; Yokota, Chiaki; Koshino, Kazuhiro; Temma, Takashi; Yamazaki, Makoto; Iguchi, Satoshi; Shimomura, Ryo; Uehara, Toshiyuki; Funatsu, Naoko; Hino, Tenyu; Minematsu, Kazuo; Iida, Hidehiro; Toyoda, Kazunori

    2017-04-01

    11 C-Pittsburgh compound-B ( 11 C-PIB) positron emission tomography (PET) is used to visualize and quantify amyloid deposition in the brain cortex in pathological conditions such as Alzheimer's disease (AD). Intense 11 C-PIB retention is also observed in the white matter (WM) of both healthy individuals and AD patients. However, the clinical implications of this retention in brain WM have not been clarified. We investigated the relationship between the extent of white matter lesions (WMLs) and the binding potential of 11 C-PIB (BP ND ) in the WM in patients with hypertensive small vessel disease. We further examined the relationship between the extent of WMLs and BP ND in WML and in normal-appearing white matter (NAWM). Twenty-one hypertensive vasculopathy patients, without AD and major cerebral arterial stenosis and/or occlusion, were enrolled (9 women, 68 ± 7 years). Regions of WML and NAWM were extracted using magnetization-prepared rapid gradient-echo and fluid-attenuated inversion recovery of magnetic resonance images. Volumes of interest (VOIs) were set in the cortex-subcortex, basal ganglia, and centrum semiovale (CS). BP ND in the cortex-subcortex, basal ganglia, CS, WML, and NAWM were estimated on 11 C-PIB PET using Logan graphical analysis with cerebellar regions as references. The relationships between WML volume and BP ND in each region were examined by linear regression analysis. BP ND was higher in the CS and basal ganglia than in the cortex-subcortex regions. WML volume had a significant inverse correlation with BP ND in the CS (Slope = -0.0042, R 2  = 0.44, P < 0.01). For intra WM comparison, BP ND in NAWM was significantly higher than that in WML. In addition, although there were no correlations between WML volume and BP ND in WML, WML volume was significantly correlated inversely with BP ND in NAWM (Slope = -0.0017, R 2  = 0.26, P = 0.02). 11 C-PIB could be a marker of not only cortical amyloid-β deposition but also

  20. 46 CFR 4.03-35 - Nuclear vessel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2012-10-01 2012-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

  1. 46 CFR 4.03-35 - Nuclear vessel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2013-10-01 2013-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

  2. 46 CFR 4.03-35 - Nuclear vessel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2014-10-01 2014-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

  3. 46 CFR 4.03-35 - Nuclear vessel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2010-10-01 2010-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

  4. 46 CFR 4.03-35 - Nuclear vessel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2011-10-01 2011-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

  5. Vessel Sampling and Blood Flow Velocity Distribution With Vessel Diameter for Characterizing the Human Bulbar Conjunctival Microvasculature.

    PubMed

    Wang, Liang; Yuan, Jin; Jiang, Hong; Yan, Wentao; Cintrón-Colón, Hector R; Perez, Victor L; DeBuc, Delia C; Feuer, William J; Wang, Jianhua

    2016-03-01

    This study determined (1) how many vessels (i.e., the vessel sampling) are needed to reliably characterize the bulbar conjunctival microvasculature and (2) if characteristic information can be obtained from the distribution histogram of the blood flow velocity and vessel diameter. Functional slitlamp biomicroscope was used to image hundreds of venules per subject. The bulbar conjunctiva in five healthy human subjects was imaged on six different locations in the temporal bulbar conjunctiva. The histograms of the diameter and velocity were plotted to examine whether the distribution was normal. Standard errors were calculated from the standard deviation and vessel sample size. The ratio of the standard error of the mean over the population mean was used to determine the sample size cutoff. The velocity was plotted as a function of the vessel diameter to display the distribution of the diameter and velocity. The results showed that the sampling size was approximately 15 vessels, which generated a standard error equivalent to 15% of the population mean from the total vessel population. The distributions of the diameter and velocity were not only unimodal, but also somewhat positively skewed and not normal. The blood flow velocity was related to the vessel diameter (r=0.23, P<0.05). This was the first study to determine the sampling size of the vessels and the distribution histogram of the blood flow velocity and vessel diameter, which may lead to a better understanding of the human microvascular system of the bulbar conjunctiva.

  6. Measuring faculty retention and success in academic medicine.

    PubMed

    Ries, Andrew; Wingard, Deborah; Gamst, Anthony; Larsen, Catherine; Farrell, Elizabeth; Reznik, Vivian

    2012-08-01

    To develop and demonstrate the usefulness of quantitative methods for assessing retention and academic success of junior faculty in academic medicine. The authors created matched sets of participants and nonparticipants in a junior faculty development program based on hire date and academic series for newly hired assistant professors at the University of California, San Diego (UCSD), School of Medicine between 1988 and 2005. They used Kaplan-Meier and Cox proportional hazards survival analyses to characterize the influence of covariates, including gender, ethnicity, and program participation, on retention. They also developed a new method for quantifying academic success based on several measures including (1) leadership and professional activities, (2) honors and awards, (3) research grants, (4) teaching and mentoring/advising activities, and (5) publications. The authors then used these measures to compare matched pairs of participating and nonparticipating faculty who were subsequently promoted and remained at UCSD. Compared with matched nonparticipants, the retention of junior faculty who participated in the faculty development program was significantly higher. Among those who were promoted and remained at UCSD, the academic success of faculty development participants was consistently greater than that of matched nonparticipants. This difference reached statistical significance for leadership and professional activities. Using better quantitative methods for evaluating retention and academic success will improve understanding and research in these areas. In this study, use of such methods indicated that organized junior faculty development programs have positive effects on faculty retention and may facilitate success in academic medicine.

  7. 46 CFR 126.225 - Alternate tonnage for offshore supply vessels seeking oil spill response vessel certification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... oil spill response vessel certification. 126.225 Section 126.225 Shipping COAST GUARD, DEPARTMENT OF... Inspection § 126.225 Alternate tonnage for offshore supply vessels seeking oil spill response vessel... also be certificated as an oil spill response vessel. [82-004 and CGD 86-074, 62 FR 49324, Sept. 19...

  8. 46 CFR 126.225 - Alternate tonnage for offshore supply vessels seeking oil spill response vessel certification.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... oil spill response vessel certification. 126.225 Section 126.225 Shipping COAST GUARD, DEPARTMENT OF... Inspection § 126.225 Alternate tonnage for offshore supply vessels seeking oil spill response vessel... also be certificated as an oil spill response vessel. [82-004 and CGD 86-074, 62 FR 49324, Sept. 19...

  9. Review of retention strategies in longitudinal studies and application to follow-up of ICU survivors.

    PubMed

    Tansey, Catherine M; Matté, Andrea L; Needham, Dale; Herridge, Margaret S

    2007-12-01

    To review the literature on retention strategies in follow-up studies and their relevance to critical care and to comment on the Toronto experience with the acute respiratory distress syndrome (ARDS) and severe acute respiratory syndrome (SARS) follow-up studies. Literature review and two cohort studies in a tertiary care hospital in Toronto, Canada. ARDS and SARS patients. Review articles from the social sciences and medicine are summarized and our own experience with two longitudinal studies is drawn upon to elucidate strategies that can be successfully used to attenuate participant drop-out from longitudinal studies. Three key areas for retention of subjects are identified from the literature: (a) respect for patients: respect for their ideas and their time commitment to the research project; (b) tracking: collect information on many patient contacts at the initiation of the study and outline tracking procedures for subjects lost to follow-up; and (c) study personnel: interpersonal skills must be reinforced, flexible working hours mandated, and support offered. Our 5-year ARDS and 1-year SARS study retention rates were 86% and 91%, respectively, using these methods. Strategies to reduce patient attrition are time consuming but necessary to preserve internal and external validity. When the follow-up system is working effectively, researchers can acquire the necessary data to advance knowledge in their field and patients are satisfied that they have an important role to play in the research project.

  10. Targeting Therapy Resistant Tumor Vessels

    DTIC Science & Technology

    2007-05-01

    Porkka K, Laakko- nen P, Ruoslahti E. Nucleolin expressed at the cell surface is a marker of endothelial cells in angiogenic blood vessels. J Cell...anti-angiogenic therapy. Markers of such vessels will be useful in developing strategies for complete destruction of breast cancer vasculature, and in...express specific markers , and that these lymphatic markers are tumor type specific and distinct from blood vessel markers in the same tumors. The

  11. An update on the blood vessel in migraine

    PubMed Central

    Brennan, K.C.; Charles, Andrew

    2017-01-01

    Purpose of review The cranial blood vessel is considered an integral player in the pathophysiology of migraine, but its perceived role has been subject to much discussion and controversy over the years. We will discuss the evolution in our scientific understanding of cranial blood vessels (primarily arteries) in migraine. Recent findings Recent developments have clarified the role of cranial blood vessels in the trigemino-vascular system and in cortical spreading depression. An underlying theme is the intimate relation between vascular activity and neural function, and we will emphasize the various roles of the blood vessel that go beyond delivering blood. We conclude that migraine cannot be understood, either from a research or clinical point of view, without an understanding of the vascular derangements that accompany it. Summary Migraine is accompanied by significant derangements in vascular function that may represent important targets for investigation and treatment. PMID:20216215

  12. Level indicator for pressure vessels

    DOEpatents

    Not Available

    1982-04-28

    A liquid-level monitor for tracking the level of a coal slurry in a high-pressure vessel including a toroidal-shaped float with magnetically permeable bands thereon disposed within the vessel, two pairs of magnetic-field generators and detectors disposed outside the vessel adjacent the top and bottom thereof and magnetically coupled to the magnetically permeable bands on the float, and signal-processing circuitry for combining signals from the top and bottom detectors for generating a monotonically increasing analog control signal which is a function of liquid level. The control signal may be utilized to operate high-pressure control valves associated with processes in which the high-pressure vessel is used.

  13. Small vessels, dementia and chronic diseases - molecular mechanisms and pathophysiology.

    PubMed

    Horsburgh, Karen; Wardlaw, Joanna M; van Agtmael, Tom; Allan, Stuart M; Ashford, Mike L J; Bath, Philip M; Brown, Rosalind; Berwick, Jason; Cader, M Zameel; Carare, Roxana O; Davis, John B; Duncombe, Jessica; Farr, Tracy D; Fowler, Jill H; Goense, Jozien; Granata, Alessandra; Hall, Catherine N; Hainsworth, Atticus H; Harvey, Adam; Hawkes, Cheryl A; Joutel, Anne; Kalaria, Rajesh N; Kehoe, Patrick G; Lawrence, Catherine B; Lockhart, Andy; Love, Seth; Macleod, Malcolm R; Macrae, I Mhairi; Markus, Hugh S; McCabe, Chris; McColl, Barry W; Meakin, Paul J; Miller, Alyson; Nedergaard, Maiken; O'Sullivan, Michael; Quinn, Terry J; Rajani, Rikesh; Saksida, Lisa M; Smith, Colin; Smith, Kenneth J; Touyz, Rhian M; Trueman, Rebecca C; Wang, Tao; Williams, Anna; Williams, Steven C R; Work, Lorraine M

    2018-04-30

    Cerebral small vessel disease (SVD) is a major contributor to stroke, cognitive impairment and dementia with limited therapeutic interventions. There is a critical need to provide mechanistic insight and improve translation between pre-clinical research and the clinic. A 2-day workshop was held which brought together experts from several disciplines in cerebrovascular disease, dementia and cardiovascular biology, to highlight current advances in these fields, explore synergies and scope for development. These proceedings provide a summary of key talks at the workshop with a particular focus on animal models of cerebral vascular disease and dementia, mechanisms and approaches to improve translation. The outcomes of discussion groups on related themes to identify the gaps in knowledge and requirements to advance knowledge are summarized. © 2018 The Author(s). Published by Portland Press Limited on behalf of the Biochemical Society.

  14. 46 CFR 70.05-18 - Applicability to vessels operating under an exemption afforded in the Passenger Vessel Safety Act...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... later than December 21, 1996. The PVSA exemption is valid for the service life of the vessel, as long as... certain passenger vessels that are— (1) At least 100 gross tons but less than 300 gross tons; or (2) Former public vessels of at least 100 gross tons but less than 500 gross tons. (b) The owner or operator...

  15. 46 CFR 70.05-18 - Applicability to vessels operating under an exemption afforded in the Passenger Vessel Safety Act...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... later than December 21, 1996. The PVSA exemption is valid for the service life of the vessel, as long as... certain passenger vessels that are— (1) At least 100 gross tons but less than 300 gross tons; or (2) Former public vessels of at least 100 gross tons but less than 500 gross tons. (b) The owner or operator...

  16. Visual implant elastomer and anchor tag retention in largemouth bass

    USGS Publications Warehouse

    Hartman, K.J.; Janney, E.C.

    2006-01-01

    We double-marked largemouth bass Micropterus salmoides with Floy FD-68B anchor tags and visible implant elastomer (VIE) marks before stocking to compare retention of the two marks for age-0 (178 mm total length [TL]) and age-1 (273 mm TL) largemouth bass. In a short-term (31-d) evaluation, retention rate of anchor tags was over 94% for each age-class and retention of VIE marks was 98% in both age-classes. In a longer-term comparison of fish stocked into the Ohio River, retention was substantially higher for VIE marks (92.9%) than for anchor tags (42.9%) after 403 d (ages combined). Although anchor tags had high retention in two sizes of largemouth bass during the short-term experiment, they should not be used in situations where accurate identification of marked fish is required for periods longer than 123 d. ?? Copyright by the American Fisheries Society 2006.

  17. Quantification of pulmonary vessel diameter in low-dose CT images

    NASA Astrophysics Data System (ADS)

    Rudyanto, Rina D.; Ortiz de Solórzano, Carlos; Muñoz-Barrutia, Arrate

    2015-03-01

    Accurate quantification of vessel diameter in low-dose Computer Tomography (CT) images is important to study pulmonary diseases, in particular for the diagnosis of vascular diseases and the characterization of morphological vascular remodeling in Chronic Obstructive Pulmonary Disease (COPD). In this study, we objectively compare several vessel diameter estimation methods using a physical phantom. Five solid tubes of differing diameters (from 0.898 to 3.980 mm) were embedded in foam, simulating vessels in the lungs. To measure the diameters, we first extracted the vessels using either of two approaches: vessel enhancement using multi-scale Hessian matrix computation, or explicitly segmenting them using intensity threshold. We implemented six methods to quantify the diameter: three estimating diameter as a function of scale used to calculate the Hessian matrix; two calculating equivalent diameter from the crosssection area obtained by thresholding the intensity and vesselness response, respectively; and finally, estimating the diameter of the object using the Full Width Half Maximum (FWHM). We find that the accuracy of frequently used methods estimating vessel diameter from the multi-scale vesselness filter depends on the range and the number of scales used. Moreover, these methods still yield a significant error margin on the challenging estimation of the smallest diameter (on the order or below the size of the CT point spread function). Obviously, the performance of the thresholding-based methods depends on the value of the threshold. Finally, we observe that a simple adaptive thresholding approach can achieve a robust and accurate estimation of the smallest vessels diameter.

  18. Electrically conductive containment vessel for molten aluminum

    DOEpatents

    Holcombe, C.E.; Scott, D.G.

    1984-06-25

    The present invention is directed to a containment vessel which is particularly useful in melting aluminum. The vessel of the present invention is a multilayered vessel characterized by being electrically conductive, essentially nonwettable by and nonreactive with molten aluminum. The vessel is formed by coating a tantalum substrate of a suitable configuration with a mixture of yttria and particulate metal 10 borides. The yttria in the coating inhibits the wetting of the coating while the boride particulate material provides the electrical conductivity through the vessel. The vessel of the present invention is particularly suitable for use in melting aluminum by ion bombardment.

  19. Electrically conductive containment vessel for molten aluminum

    DOEpatents

    Holcombe, Cressie E.; Scott, Donald G.

    1985-01-01

    The present invention is directed to a containment vessel which is particularly useful in melting aluminum. The vessel of the present invention is a multilayered vessel characterized by being electrically conductive, essentially nonwettable by and nonreactive with molten aluminum. The vessel is formed by coating a tantalum substrate of a suitable configuration with a mixture of yttria and particulate metal borides. The yttria in the coating inhibits the wetting of the coating while the boride particulate material provides the electrical conductivity through the vessel. The vessel of the present invention is particularly suitable for use in melting aluminum by ion bombardment.

  20. Participant Retention in the Veterans Health Administration’s MOVE! Weight Management Program, 2010

    PubMed Central

    Sohn, Min-Woong; Spring, Bonnie; Hadi, Sattar; Weaver, Frances M.

    2012-01-01

    Introduction Participant retention is a frequent concern in structured weight-management programs. Although research has explored participant characteristics influencing retention, little attention has been given to the influence of program characteristics. The objective of this study was to examine how program characteristics relate to participant retention in the Veterans Health Administration’s weight-management program, MOVE! Methods We conducted semistructured interviews with coordinators of 12 MOVE! programs located throughout the United States, 5 with high participant retention rates and 7 with low rates. We transcribed and descriptively coded interviews and compared responses from high- and low-retention programs. Results Characteristics related to retention were provider knowledge of and referral to the program, reputation of the program within the medical facility, the MOVE! meeting schedule, inclusion of physical activity in group meetings, and involvement of the MOVE! physician champion. MOVE! introductory sessions, frequency of group meetings, and meeting topics were not related to retention. Coordinators described efforts to improve retention, including participant contracts and team competitions. Coordinators at 5 high-retention facilities and 1 low-retention facility discussed efforts to improve retention. Conclusion Coordinators identified important program characteristics that could guide improvements to retention in group-based weight-management programs. Training for providers is needed to assist with referral decisions, and program planners should consider incorporating physical activity in group meetings. PMID:22814235

  1. Biocompatible KMnF3 nanoparticular contrast agent with proper plasma retention time for in vivo magnetic resonance imaging.

    PubMed

    Liu, Zhi-jun; Song, Xiao-xia; Xu, Xian-zhu; Tang, Qun

    2014-04-18

    Nanoparticular MRI contrast agents are rapidly becoming suitable for use in clinical diagnosis. An ideal nanoparticular contrast agent should be endowed with high relaxivity, biocompatibility, proper plasma retention time, and tissue-specific or tumor-targeting imaging. Herein we introduce PEGylated KMnF3 nanoparticles as a new type of T1 contrast agent. Studies showed that the nanoparticular contrast agent revealed high bio-stability with bovine serum albumin in PBS buffer solution, and presented excellent biocompatibility (low cytotoxicity, undetectable hemolysis and hemagglutination). Meanwhile the new contrast agent possessed proper plasma retention time (circulation half-life t1/2 is approximately 2 h) in the body of the administrated mice. It can be delivered into brain vessels and maintained there for hours, and is mostly cleared from the body within 48 h, as demonstrated by time-resolved MRI and Mn-biodistribution analysis. Those distinguishing features make it suitable to obtain contrast-enhanced brain magnetic resonance angiography. Moreover, through the process of passive targeting delivery, the T1 contrast agent clearly illuminates a brain tumor (glioma) with high contrast image and defined shape. This study demonstrates that PEGylated KMnF3 nanoparticles represent a promising biocompatible vascular contrast agent for magnetic resonance angiography and can potentially be further developed into an active targeted tumor MRI contrast agent.

  2. Is there a crisis in nursing retention in New South Wales?

    PubMed Central

    Doiron, Denise; Hall, Jane; Jones, Glenn

    2008-01-01

    Background There is a severe shortage of nurses in Australia. Policy makers and researchers are especially concerned that retention levels of nurses in the health workforce have worsened over the last decade. There are also concerns that rapidly growing private sector hospitals are attracting qualified nurses away from the public sector. To date no systematic analysis of trends in nursing retention rates over time has been conducted due to the lack of consistent panel data. Results A 1.4 percentage point improvement in retention has led to a 10% increase in the overall supply of nurses in NSW. There has also been a substantial aging of the workforce, due to greater retention and an increase in mature age entrants. The improvement in retention is found in all types of premises and is largest in nursing homes. There is a substantial amount of year to year movement in and out of the workforce and across premises. The shortage of nurses in public hospitals is due to a slowdown in entry rather than competition from the rapidly growing private sector hospitals. Policy Implications The finding of an improvement (rather than a worsening) in retention suggests that additional improvements may be difficult to achieve as further retention must involve individuals more and more dissatisfied with nursing relative to other opportunities. Hence policies targeting entry such as increased places in nursing programs and additional subsidies for training costs may be more effective in dealing with the workforce shortage. This is also the case for shortages in public sector hospitals as retention in nursing is found to be relatively high in this sector. However, the large amount of year to year movements across nursing jobs, especially among the younger nurses, also suggests that policies aimed at reducing job switches and increasing the number who return to nursing should also be pursued. More research is needed in understanding the relative importance of detailed working conditions

  3. What predicts retention on an in-prison drug treatment program?

    PubMed

    Casares-López, María José; González-Menéndez, Ana; Fernández, Paula; Secades-Villa, Roberto; Fernández-Hermida, José Ramón

    2012-11-01

    The effectiveness of treatments for substance use disorders is strongly related to retention, since early dropout from treatment is associated with greater likelihood of relapse. The purpose of this prospective, ex post facto study is to analyze the effect of individual variables on retention in a treatment program carried out in a prison drug-free unit. The Addiction Severity Index, motivation and personality profile of fifty inmates were assessed on entry to the prison. Inmates were monitored for a year to identify length of stay. Motivation variables at intake play a vital role in the prediction of retention in a prison drug-free unit; scores on the Aggressive-Sadistic and Narcissistic scales are also strong predictors of treatment retention.

  4. 46 CFR 169.249 - Pressure vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Pressure vessels. 169.249 Section 169.249 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Inspection and Certification Inspections § 169.249 Pressure vessels. Pressure vessels must meet the requirements...

  5. 46 CFR 169.249 - Pressure vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Pressure vessels. 169.249 Section 169.249 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Inspection and Certification Inspections § 169.249 Pressure vessels. Pressure vessels must meet the requirements...

  6. 19 CFR 4.80 - Vessels entitled to engage in coastwise trade.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Vessels entitled to engage in coastwise trade. 4...; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Coastwise Procedure § 4.80 Vessels entitled to engage in coastwise trade. (a) No vessel shall transport, either directly or by way of a foreign...

  7. 19 CFR 4.80 - Vessels entitled to engage in coastwise trade.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Vessels entitled to engage in coastwise trade. 4...; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Coastwise Procedure § 4.80 Vessels entitled to engage in coastwise trade. (a) No vessel shall transport, either directly or by way of a foreign...

  8. 19 CFR 4.80 - Vessels entitled to engage in coastwise trade.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Vessels entitled to engage in coastwise trade. 4...; DEPARTMENT OF THE TREASURY VESSELS IN FOREIGN AND DOMESTIC TRADES Coastwise Procedure § 4.80 Vessels entitled to engage in coastwise trade. (a) No vessel shall transport, either directly or by way of a foreign...

  9. 75 FR 39957 - Certificate of Alternative Compliance for the Offshore Supply Vessel/Well Stimulation Vessel BLUE...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-13

    ... Compliance for the Offshore Supply Vessel/Well Stimulation Vessel BLUE TARPON AGENCY: Coast Guard, DHS... issued for the offshore supply vessel BLUE TARPON as required by 33 U.S.C. 1605(c) and 33 CFR 81.18... Regulation, Parts 81 and 89, has been issued for the offshore supply vessel BLUE TARPON, O.N. 1226288. The...

  10. [Academic stress, desertion, and retention strategies for students in higher education].

    PubMed

    Suárez-Montes, Nancy; Díaz-Subieta, Luz B

    2015-04-01

    A systematic review was performed to specify the characteristics of academic stress that affect the mental health of the university population. To do this, recent publications regarding academic stress, student desertion, and retention strategies were examined. Throughout this text, we present the results of the review in terms of the definitions of academic stress, student desertion, and retention strategies. In the same way, we examine the interpretative models with regard to student desertion and approach retention strategies in higher education. We also review retention experiences of several other countries. In terms of Colombia, we present aspects related to student desertion and retention programs from the point of view of the National Ministry of Education and from the experience of some universities with consolidated programs.

  11. Study on vessel sewage treatment technologies

    NASA Astrophysics Data System (ADS)

    Shen, Wei; Xing, Guojing

    2017-10-01

    In this paper, the author, on the basis of his experience in researches of past years, discusses the status quo and classifications of vessel sewage treatment technology, analyzes problems plaguing current vessel sewage treatment and describes the focuses of development of vessel sewage treatment technology.

  12. Abnormal myocardial fluid retention as an early manifestation of ischemic injury.

    PubMed Central

    Willerson, J. T.; Scales, F.; Mukherjee, A.; Platt, M.; Templeton, G. H.; Fink, G. S.; Buja, L. M.

    1977-01-01

    Fifty-seven isolated, blood perfused, continuously weighed canine hearts have been utilized to study the development of abnormal myocardial fluid retention during early myocardial ischemic injury. Inflatable balloon catheters were positioned around the left anterior descending coronary arteries (LAD) of 54 hearts or the proximal left circumflex coronary arteries of three hearts for study of the following intervals of coronary occlusion: a) 10 minutes followed by 20 minutes of reflow, b) 40 minutes followed by either no reflow or by 20 minutes of reflow, and c) 60 minutes without reflow. After 60 minutes of fixed coronary occlusion, histologic and ultrastructural examination revealed mild swelling of many ischemic cardiac muscle cells in the absence of interstitial edema, cardiac weight gain, and obvious structural defects in cell membrane integrity. After 40 minutes of coronary occlusion and 20 minutes of reflow, significant cardiac weight gain occurred in association with characteristic alterations in the ischemic region, including widespread interstitial edema and focal vascular congestion and hemorrhage and swelling of cardiac muscle cells. Focal structural defects in cell membrane integrity were also noted. The development of abnormal myocardial fluid retention after 40 minutes of LAD occlusion occurred in association with a significant reduction in sodium-potassium-ATPase activity in the ischemic area, but with no significant alteration in either creatine phosphokinase or citrate synthase activity in the same region. Despite the abnormal myocardial fluid retention in these hearts, it was possible pharmacologically to vasodilate coronary vessels with adenosine and nitroglycerin infusion to maintain a consistently high coronary flow following release of the coronary occlusion after 40 minutes and to even exceed initial hyperemic flow values following release of the occlusion when adenosine and nitroglycerin infusion was delayed until 15 minutes after reflow

  13. Spatial variation of vessel grouping in the xylem of Betula platyphylla Roth.

    PubMed

    Zhao, Xiping

    2016-01-01

    Vessel grouping in angiosperms may improve hydraulic integration and increase the spread of cavitations through redundancy pathways. Although disputed, it is increasingly attracting research interest as a potentially significant hydraulic trait. However, the variation of vessel grouping in a tree is poorly understood. I measured the number of solitary and grouped vessels in the xylem of Betula platyphylla Roth. from the pith to the bark along the water flow path. The vessel grouping parameters included the mean number of vessels per vessel group (VG), percentage of solitary vessels (SVP), percentage of radial multiple vessels (MVP), and percentage of cluster vessels (CVP). The effects of cambial age (CA) and flow path-length (PL) on the vessel grouping were analyzed using a linear mixed model.VG and CVP increased nonlinearly, SVP decreased nonlinearly with PL. In trunks and branches, VG and CVP decreased nonlinearly, and SVP increased nonlinearly with CA. In roots, the parameters had no change with CA. MVP was almost constant with PL or CA. The results suggest that vessel grouping has a nonrandom variation pattern, which is affected deeply by cambial age and water flow path.

  14. Data Retention and Anonymity Services

    NASA Astrophysics Data System (ADS)

    Berthold, Stefan; Böhme, Rainer; Köpsell, Stefan

    The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable security of systems for anonymous communication on the Internet. We argue that data retention requires a review of existing security evaluations against a new class of realistic adversary models. In particular, we present theoretical results and first empirical evidence for intersection attacks by law enforcement authorities. The reference architecture for our study is the anonymity service AN.ON, from which we also collect empirical data. Our adversary model reflects an interpretation of the current implementation of the EC Directive on Data Retention in Germany.

  15. Sexual dimorphism in stature (SDS), jealousy and mate retention.

    PubMed

    Brewer, Gayle; Riley, Charlene

    2010-10-02

    Previous research has investigated the manner in which absolute height impacts on jealousy and mate retention. Although relative height is also important, little information exists about the potential influence of sexual dimorphism in stature (SDS) within established relationships. The current study investigated the relationship between SDS and the satisfaction, jealousy and mate retention behaviors reported by men and women. Heterosexual men (n = 98) and women (n = 102) completed a questionnaire. Men in high SDS relationships reported the lowest levels of cognitive and behavioral jealousy, although the impact of SDS on relationship satisfaction was less clear. SDS was not associated with the overall use of mate retention strategies; SDS did however affect the use of three specific strategies (vigilance, monopolization of time, love and care). SDS did not affect women's relationship satisfaction, jealousy (cognitive, behavioral, or emotional) or the use of mate retention strategies (with the exception of resource display).

  16. [Systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography].

    PubMed

    Fu, Qing; Wang, Jun; Liang, Tu; Xu, Xiaoyong; Jin, Yu

    2013-11-01

    A systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography (HILIC) was performed. The influences of mobile phase, stationary phase and buffer salt on the retention of carbohydrates were investigated. According to the results, the retention time of carbohydrates decreased as the proportion of acetonitrile in mobile phase decreased. Increased time of carbohydrates was observed as the concentration of buffer salt in mobile phase increased. The retention behavior of carbohydrates was also affected by organic solvent and HILIC stationary phase. Furthermore, an appropriate retention equation was used in HILIC mode. The retention equation lnk = a + blnC(B) + cC(B) could quantitatively describe the retention factors of carbohydrates of plant origin with good accuracy: the relative error of the predicted time to actual time was less than 0.3%. The evaluation results could provide guidance for carbohydrates to optimize the experimental conditions in HILIC method development especially for carbohydrate separation

  17. Automatic retinal blood vessel parameter calculation in spectral domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Wehbe, Hassan; Ruggeri, Marco; Jiao, Shuliang; Gregori, Giovanni; Puliafito, Carmen A.

    2007-02-01

    Measurement of retinal blood vessel parameters like the blood blow in the vessels may have significant impact on the study and diagnosis of glaucoma, a leading blinding disease worldwide. Optical coherence tomography (OCT) is a noninvasive imaging technique that can provide not only microscopic structural imaging of the retina but also functional information like the blood flow velocity in the retina. The aim of this study is to automatically extract the parameters of retinal blood vessels like the 3D orientation, the vessel diameters, as well as the corresponding absolute blood flow velocity in the vessel. The parameters were extracted from circular OCT scans around the optic disc. By removing the surface reflection through simple segmentation of the circular OCT scans a blood vessel shadowgram can be generated. The lateral coordinates and the diameter of each blood vessel are extracted from the shadowgram through a series of signal processing. Upon determination of the lateral position and the vessel diameter, the coordinate in the depth direction of each blood vessel is calculated in combination with the Doppler information for the vessel. The extraction of the vessel coordinates and diameter makes it possible to calculate the orientation of the vessel in reference to the direction of the incident sample light, which in turn can be used to calculate the absolute blood flow velocity and the flow rate.

  18. Molecular Mechanisms Controlling GLUT4 Intracellular Retention

    PubMed Central

    Blot, Vincent

    2008-01-01

    In basal adipocytes, glucose transporter 4 (GLUT4) is sequestered intracellularly by an insulin-reversible retention mechanism. Here, we analyze the roles of three GLUT4 trafficking motifs (FQQI, TELEY, and LL), providing molecular links between insulin signaling, cellular trafficking machinery, and the motifs in the specialized trafficking of GLUT4. Our results support a GLUT4 retention model that involves two linked intracellular cycles: one between endosomes and a retention compartment, and the other between endosomes and specialized GLUT4 transport vesicles. Targeting of GLUT4 to the former is dependent on the FQQI motif and its targeting to the latter is dependent on the TELEY motif. These two motifs act independently in retention, with the TELEY-dependent step being under the control of signaling downstream of the AS160 rab GTPase activating protein. Segregation of GLUT4 from endosomes, although positively correlated with the degree of basal retention, does not completely account for GLUT4 retention or insulin-responsiveness. Mutation of the LL motif slows return to basal intracellular retention after insulin withdrawal. Knockdown of clathrin adaptin protein complex-1 (AP-1) causes a delay in the return to intracellular retention after insulin withdrawal. The effects of mutating the LL motif and knockdown of AP-1 were not additive, establishing that AP-1 regulation of GLUT4 trafficking requires the LL motif. PMID:18550797

  19. STEEL FOR PRESSURE VESSELS FOR POWER REACTORS (in German)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zastrow, E.

    1960-11-01

    Both gas-cooled and water-cooled reactors place on the steel pressure vessel rigid requirements with respect to the design, radiation stability, gamma -induced internal stresses, and inability to, or difficulty in, repairing the vessel once it is installed. The factors to be considered in the selection of a given steel for a pressure vessel are reviewed, and the properties of steels previously used for this purpose are tabulated. The studies being raade at present to improve the desirable properties of steels for pressure vessels are briefly summarized. The corrosion stability and irradiation stability of steel are discussed. Neutron activation of themore » steel is also briefly reviewed. (J.S.R.)« less

  20. The effect of dentifrice quantity and toothbrushing behaviour on oral delivery and retention of fluoride in vivo.

    PubMed

    Creeth, Jonathan; Zero, Domenick; Mau, Melissa; Bosma, Mary Lynn; Butler, Andrew

    2013-12-01

    While toothpaste F(-) concentration and rinsing regimen have well-characterised impacts on fluoride's effectiveness, other aspects of brushing regimen have much less well-established effects, in particular, dentifrice quantity and brushing duration. An in vivo study (n = 42) of oral fluoride delivery (i.e. oral disposition post-brushing), and retention (i.e. concentration of F(-) in saliva post-brushing, a known efficacy predictor), was performed to compare effects observed with those of dentifrice F(-) concentration and rinsing regimen. Subjects brushed with a NaF-silica dentifrice (Aquafresh Advanced, 1,150 ppm F(-) ) or a control dentifrice (250 ppm F(-) , same base), for 45, 60, 120 or 180 seconds with 0.5 or 1.5 g dentifrice, and rinsed with 15 ml water once or three times in a cross-over design. The F(-) concentration was measured in post-brushing expectorate, rinse and toothbrush washing samples, and in saliva between 5-120 minutes after brushing. Using 1.5 g versus 0.5 g dentifrice increased F(-) in all samples: oral retention of F(-) was almost doubled by this increase. Increasing duration of brushing had more complex effects. The amount of F(-) in the expectorate increased but decreased in both rinse and toothbrush washing samples. Oral F(-) retention increased, but only in the period 30-120 minutes after brushing. Over the ranges investigated, the order of importance on oral F(-) retention was: dentifrice F(-) concentration > quantity > rinsing regimen > brushing duration. Hence, increasing dentifrice quantity and, to a lesser extent, the duration of brushing, can elevate oral fluoride post-brushing. Evidence is accumulating that the importance of these variables to fluoride efficacy may have been underestimated. © 2013 FDI World Dental Federation.

  1. A scaling law for the local CHF on the external bottom side of a fully submerged reactor vessel

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cheung, F.B.; Haddad, K.H.; Liu, Y.C.

    1997-02-01

    A scaling law for estimating the local critical heat flux on the outer surface of a heated hemispherical vessel that is fully submerged in water has been developed from the results of an advanced hydrodynamic CHF model for pool boiling on a downward facing curved heating surface. The scaling law accounts for the effects of the size of the vessel, the level of liquid subcooling, the intrinsic properties of the fluid, and the spatial variation of the local critical heat flux along the heating surface. It is found that for vessels with diameters considerably larger than the characteristic size ofmore » the vapor masses, the size effect on the local critical heat flux is limited almost entirely to the effect of subcooling associated with the local liquid head. When the subcooling effect is accounted for separately, the local CHF limit is nearly independent of the vessel size. Based upon the scaling law developed in this work, it is possible to merge, within the experimental uncertainties, all the available local CHF data obtained for various vessel sizes under both saturated and subcooled boiling conditions into a single curve. Applications of the scaling law to commercial-size vessels have been made for various system pressures and water levels above the heated vessel. Over the range of conditions explored in this study, the local CHF limit is found to increase by a factor of two or more from the bottom center to the upper edge of the vessel. Meanwhile, the critical heat flux at a given angular position of the heated vessel is also found to increase appreciably with the system pressure and the water level.« less

  2. Retention in Special Education Teachers in Georgia: A Phenomenological Approach

    ERIC Educational Resources Information Center

    Jackson, Arndra N.

    2012-01-01

    The purpose of this qualitative study using a phenomenological approach was to identify and examine factors influencing the retention rate of special education teachers in rural and urban schools in middle Georgia. Provided in this study are factors that are related to retention in special education teachers. Semistructured interviews were used to…

  3. Urinary retention and post-void residual urine in men: separating truth from tradition.

    PubMed

    Kaplan, Steven A; Wein, Alan J; Staskin, David R; Roehrborn, Claus G; Steers, William D

    2008-07-01

    The definitions of acute and chronic urinary retention remain empirical and subject to wide interpretation. Standardized criteria have not been established and many questions remain unanswered. Moreover, the definition of significant post-void residual urine is unclear. We reviewed several aspects of urinary retention that require clarification with the objective of stimulating discussion among urologists to establish an accurate and coherent definition of urinary retention and significant post-void residual urine, and clarify risk factors. A MEDLINE search for articles written in English and published before April 2007 was done using a list of terms related to urinary retention. Articles not directly relevant to urinary retention or post-void residual urine were excluded. The term urinary retention lacks precise clinical or urodynamic meaning. Use of this term to describe a symptom, a sign, and a condition further complicates the issue. Many factors can contribute to the development of retention, including bladder outlet obstruction, detrusor underactivity, and neurogenic bladder conditions. Community based studies and clinical trials in patients with benign prostatic enlargement and/or lower urinary tract symptoms yield different estimates of the incidence of retention and only provide information on the epidemiology of acute urinary retention. However, age, previous retention episodes, lower urinary tract symptoms, chronic inflammation, serum prostate specific antigen level, prostate size, and urodynamic variables appear to be predictors of acute urinary retention. Alpha-receptor antagonists and 5alpha-reductase inhibitors may be useful in preventing urinary retention episodes and progressive benign prostatic enlargement. Clinical trials on the short-term use of antimuscarinics have not provided evidence that these agents increase the risk of retention; data on longer term administration are needed. Clinicians are adopting less invasive approaches (eg

  4. Vessel extraction in retinal images using automatic thresholding and Gabor Wavelet.

    PubMed

    Ali, Aziah; Hussain, Aini; Wan Zaki, Wan Mimi Diyana

    2017-07-01

    Retinal image analysis has been widely used for early detection and diagnosis of multiple systemic diseases. Accurate vessel extraction in retinal image is a crucial step towards a fully automated diagnosis system. This work affords an efficient unsupervised method for extracting blood vessels from retinal images by combining existing Gabor Wavelet (GW) method with automatic thresholding. Green channel image is extracted from color retinal image and used to produce Gabor feature image using GW. Both green channel image and Gabor feature image undergo vessel-enhancement step in order to highlight blood vessels. Next, the two vessel-enhanced images are transformed to binary images using automatic thresholding before combined to produce the final vessel output. Combining the images results in significant improvement of blood vessel extraction performance compared to using individual image. Effectiveness of the proposed method was proven via comparative analysis with existing methods validated using publicly available database, DRIVE.

  5. Strategies to improve retention in randomised trials

    PubMed Central

    Brueton, Valerie C; Tierney, Jayne; Stenning, Sally; Harding, Seeromanie; Meredith, Sarah; Nazareth, Irwin; Rait, Greta

    2013-01-01

    Background Loss to follow-up from randomised trials can introduce bias and reduce study power, affecting the generalisability, validity and reliability of results. Many strategies are used to reduce loss to follow-up and improve retention but few have been formally evaluated. Objectives To quantify the effect of strategies to improve retention on the proportion of participants retained in randomised trials and to investigate if the effect varied by trial strategy and trial setting. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PreMEDLINE, EMBASE, PsycINFO, DARE, CINAHL, Campbell Collaboration's Social, Psychological, Educational and Criminological Trials Register, and ERIC. We handsearched conference proceedings and publication reference lists for eligible retention trials. We also surveyed all UK Clinical Trials Units to identify further studies. Selection criteria We included eligible retention trials of randomised or quasi-randomised evaluations of strategies to increase retention that were embedded in 'host' randomised trials from all disease areas and healthcare settings. We excluded studies aiming to increase treatment compliance. Data collection and analysis We contacted authors to supplement or confirm data that we had extracted. For retention trials, we recorded data on the method of randomisation, type of strategy evaluated, comparator, primary outcome, planned sample size, numbers randomised and numbers retained. We used risk ratios (RR) to evaluate the effectiveness of the addition of strategies to improve retention. We assessed heterogeneity between trials using the Chi2 and I2 statistics. For main trials that hosted retention trials, we extracted data on disease area, intervention, population, healthcare setting, sequence generation and allocation concealment. Main results We identified 38 eligible retention trials. Included trials evaluated six broad types of strategies to improve retention. These

  6. Programmatic Efforts Affect Retention of Women in Science and Engineering

    NASA Astrophysics Data System (ADS)

    Hathaway, Russel S.; Sharp, Sally; Davis, Cinda-Sue

    This article presents findings from a study that investigated the impact of a women in science and engineering residence program (WISE-RP) on the retention of women in science and engineering disciplines. From a matched sample of 1,852 science and engineering students, the authors compared WISE-RP participants with male and female control students for science and engineering retention. The findings suggest a strong connection between WISE-KP participation and science retention, but not engineering retention. The results also indicate that a WISE-RP is more effective in retaining White and Asian students than underrepresented students of color. The authors highlight the importance of combining academic and personal support in a residential learning program and draw implications for retaining women т science, mathematics, and engineering disciplines.

  7. 19 CFR 4.97 - Salvage vessels.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... United States and Great Britain ‘concerning reciprocal rights for United States and Canada in the... meaning of this statute. (e) A Mexican vessel may engage in a salvage operation on a Mexican vessel in any territorial waters of the United States in which Mexican vessels are permitted to conduct such operations by...

  8. Cerebral amyloid angiopathy initially occurs in the meningeal vessels.

    PubMed

    Takeda, Shigeki; Yamazaki, Kazunori; Miyakawa, Teruo; Onda, Kiyoshi

    2017-12-01

    To clarify the frequency of CAA in the brain parenchyma and subarachnoid space (SAS), we counted sections of blood vessels showing positive staining for Aβ in the SAS, cerebral cortex (CC) and cerebral white matter (WM) using paraffin-embedded sections of the frontal, temporal and occipital lobes. The specimens had been taken for routine neuropathological examination from the brains of 105 Japanese patients (aged 40-95 years) selected from among 200 consecutive patients autopsied between 1989 and 2015 at our hospital. We examined the anatomical ratios of blood-vessel sections in the SAS relative to the CC in three selected CAA cases, and those of Aβ-positive blood-vessel sections in CAA cases. CAA was found in 53 of the 105 cases (50.5%), and the youngest patient affected was a 51-year-old man. The incidence of CAA increased with age. The anatomical ratio of blood vessel sections in the SAS relative to the CC was 1/3.70-1/4.37 (mean: 1/3.94). The ordinary CAA group, in which CAA was seen in both the SAS and CC, included 41 cases (77.4%). In 37 of these cases, the SAS/CC ratio of Aβ-positive blood vessels was 1/0.05-1/0.66 (mean: 1/0.26), and in the other four cases the ratio was 1/1-1/1.5. In the ordinary CAA group, the SAS/CC ratio of Aβ-positive blood vessels was smaller than the anatomical ratio. The meningeal CAA group, in which CAA was found only in the SAS, included 12 cases (22.6%). These patients ranged in age from their fifties to their nineties. There was no case in which CAA was limited only to the CC. We concluded that CAA initially develops in the meningeal blood vessels, and not in the cortical blood vessels. CAA in the WM was seen in 10 cases, not only in nine cases that were severe, but also in a mild case. © 2017 Japanese Society of Neuropathology.

  9. An Investigation of the Factors That Motivate K-12 Christian School Teachers to Participate in Professional Development and the Relationship to Job Satisfaction and Retention

    ERIC Educational Resources Information Center

    Bailey, Bonita Wingfield

    2013-01-01

    This study was conducted to advance knowledge by examining the reasons that motivate teachers to participate in professional development and the relationship to teacher job satisfaction and retention in Christian-based K-12 Association of Christian Schools International (ACSI) member schools. The study contributes to the literature in the field…

  10. Automatic segmentation of vessels in in-vivo ultrasound scans

    NASA Astrophysics Data System (ADS)

    Tamimi-Sarnikowski, Philip; Brink-Kjær, Andreas; Moshavegh, Ramin; Arendt Jensen, Jørgen

    2017-03-01

    Ultrasound has become highly popular to monitor atherosclerosis, by scanning the carotid artery. The screening involves measuring the thickness of the vessel wall and diameter of the lumen. An automatic segmentation of the vessel lumen, can enable the determination of lumen diameter. This paper presents a fully automatic segmentation algorithm, for robustly segmenting the vessel lumen in longitudinal B-mode ultrasound images. The automatic segmentation is performed using a combination of B-mode and power Doppler images. The proposed algorithm includes a series of preprocessing steps, and performs a vessel segmentation by use of the marker-controlled watershed transform. The ultrasound images used in the study were acquired using the bk3000 ultrasound scanner (BK Ultrasound, Herlev, Denmark) with two transducers "8L2 Linear" and "10L2w Wide Linear" (BK Ultrasound, Herlev, Denmark). The algorithm was evaluated empirically and applied to a dataset of in-vivo 1770 images recorded from 8 healthy subjects. The segmentation results were compared to manual delineation performed by two experienced users. The results showed a sensitivity and specificity of 90.41+/-11.2 % and 97.93+/-5.7% (mean+/-standard deviation), respectively. The amount of overlap of segmentation and manual segmentation, was measured by the Dice similarity coefficient, which was 91.25+/-11.6%. The empirical results demonstrated the feasibility of segmenting the vessel lumen in ultrasound scans using a fully automatic algorithm.

  11. The effect of retentive groove, sandblasting and cement type on the retentive strength of stainless steel crowns in primary second molars--an in vitro comparative study.

    PubMed

    Veerabadhran, M M; Reddy, V; Nayak, U A; Rao, A P; Sundaram, M A

    2012-01-01

    This in vitro study was conducted to find out the effect of retentive groove, sand blasting and cement type on the retentive strength of stainless steel crowns in primary second molars. Thirty-two extracted intact human maxillary and mandibular primary second molars were embedded in aluminum blocks utilizing autopolymerising acrylic resin. After tooth preparation, the 3M stainless steel crown was adjusted to the prepared tooth. Then weldable buccal tubes were welded on the buccal and lingual surfaces of each crown as an attachment for the testing machine. A full factorial design matrix for four factors (retentive groove placement on the tooth, cement type, sandblasting and primary second molar) at two levels each was developed and the study was conducted as dictated by the matrix. The lower and upper limits for each factor were without and with retentive groove placement on the tooth, GIC and RMGIC, without and with sandblasting of crown, maxillary and mandibular second primary molar. For those teeth for which the design matrix dictated groove placement, the retentive groove was placed on the middle third of the buccal surface of the tooth horizontally and for those crowns for which sandblasting of the crowns are to be done, sandblasting was done with aluminium oxide with a particle size of 250 mm. The crowns were luted with either GIC or RMGIC, as dictated by the design matrix. Then the retentive strength of each sample was evaluated by means of an universal testing machine. The obtained data was analyzed using ANOVA for statistical analysis of the data and 't'- tests for pairwise comparison. The mean retentive strength in kg/cm 2 stainless steel crowns luted with RMGIC was 19.361 and the mean retentive strength of stainless steel crowns luted with GIC was 15.964 kg/cm 2 with a mean difference of 3.397 kg/cm 2 and was statistically significant. The mean retentive strength in kg/cm 2 of stainless steel crowns, which was not sandblasted, was 18.880 and which was

  12. Sustained activation of c-Jun N-terminal and extracellular signal-regulated kinases in port-wine stain blood vessels.

    PubMed

    Tan, Wenbin; Chernova, Margarita; Gao, Lin; Sun, Victor; Liu, Huaxu; Jia, Wangcun; Langer, Stephanie; Wang, Gang; Mihm, Martin C; Nelson, J Stuart

    2014-11-01

    Port-wine stain (PWS) is a congenital, progressive vascular malformation but the pathogenesis remains incompletely understood. We sought to investigate the activation status of various kinases, including extracellular signal-regulated kinase, c-Jun N-terminal kinase, AKT, phosphatidylinositol 3-kinase, P70 ribosomal S6 kinase, and phosphoinositide phospholipase C γ subunit, in PWS biopsy tissues. Immunohistochemistry was performed on 19 skin biopsy samples from 11 patients with PWS. c-Jun N-terminal kinase, extracellular signal-regulated kinase, and P70 ribosomal S6 kinase in pediatric and adult PWS blood vessels were consecutively activated. Activation of AKT and phosphatidylinositol 3-kinase was found in many adult hypertrophic PWS blood vessels but not in infants. Phosphoinositide phospholipase C γ subunit showed strong activation in nodular PWS blood vessels. Infantile PWS sample size was small. Our data suggest a subsequent activation profile of various kinases during different stages of PWS: (1) c-Jun N-terminal and extracellular signal-regulated kinases are firstly and consecutively activated in all PWS tissues, which may contribute to both the pathogenesis and progressive development of PWS; (2) AKT and phosphatidylinositol 3-kinase are subsequently activated, and are involved in the hypertrophic development of PWS blood vessels; and (3) phosphoinositide phospholipase C γ subunit is activated in the most advanced stage of PWS and may participate in nodular formation. Copyright © 2014 American Academy of Dermatology, Inc. Published by Elsevier Inc. All rights reserved.

  13. 50 CFR 697.8 - Vessel identification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... limited access American lobster permit and over 25 ft (7.6 m) in registered length must: (1) Have affixed... fishing vessel issued a limited access American lobster permit must display its official number in block... each vessel issued a limited access American lobster permit shall ensure that— (1) The vessel's name...

  14. 50 CFR 697.8 - Vessel identification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... access American lobster permit and over 25 ft (7.6 m) in registered length must: (1) Have affixed... fishing vessel issued a limited access American lobster permit must display its official number in block... each vessel issued a limited access American lobster permit shall ensure that— (1) The vessel's name...

  15. Towards a chromatographic similarity index to establish localised quantitative structure-retention relationships for retention prediction. II Use of Tanimoto similarity index in ion chromatography.

    PubMed

    Park, Soo Hyun; Talebi, Mohammad; Amos, Ruth I J; Tyteca, Eva; Haddad, Paul R; Szucs, Roman; Pohl, Christopher A; Dolan, John W

    2017-11-10

    Quantitative Structure-Retention Relationships (QSRR) are used to predict retention times of compounds based only on their chemical structures encoded by molecular descriptors. The main concern in QSRR modelling is to build models with high predictive power, allowing reliable retention prediction for the unknown compounds across the chromatographic space. With the aim of enhancing the prediction power of the models, in this work, our previously proposed QSRR modelling approach called "federation of local models" is extended in ion chromatography to predict retention times of unknown ions, where a local model for each target ion (unknown) is created using only structurally similar ions from the dataset. A Tanimoto similarity (TS) score was utilised as a measure of structural similarity and training sets were developed by including ions that were similar to the target ion, as defined by a threshold value. The prediction of retention parameters (a- and b-values) in the linear solvent strength (LSS) model in ion chromatography, log k=a - blog[eluent], allows the prediction of retention times under all eluent concentrations. The QSRR models for a- and b-values were developed by a genetic algorithm-partial least squares method using the retention data of inorganic and small organic anions and larger organic cations (molecular mass up to 507) on four Thermo Fisher Scientific columns (AS20, AS19, AS11HC and CS17). The corresponding predicted retention times were calculated by fitting the predicted a- and b-values of the models into the LSS model equation. The predicted retention times were also plotted against the experimental values to evaluate the goodness of fit and the predictive power of the models. The application of a TS threshold of 0.6 was found to successfully produce predictive and reliable QSRR models (Q ext(F2) 2 >0.8 and Mean Absolute Error<0.1), and hence accurate retention time predictions with an average Mean Absolute Error of 0.2min. Crown Copyright

  16. 50 CFR 300.32 - Vessel licenses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Vessel licenses. 300.32 Section 300.32 Wildlife and Fisheries INTERNATIONAL FISHING AND RELATED ACTIVITIES INTERNATIONAL FISHERIES REGULATIONS South Pacific Tuna Fisheries § 300.32 Vessel licenses. (a) Each vessel fishing in the Licensing Area...

  17. Fatal occupational accidents in Danish fishing vessels 1989-2005.

    PubMed

    Laursen, Lise H; Hansen, Henrik L; Jensen, Olaf C

    2008-06-01

    The purpose of the study was to study the circumstances and incidence rates of fatal accidents in inspection obligated and non-inspection obligated Danish fishing vessels to identify areas for prevention. Information about the fatalities came from maritime authority reports, including vessel disaster reports, post mortem reports, maritime inquiries and police reports. The person- and vessel years at risk came from the Danish Directorate of Fisheries. During the period 1989-2005, 114 fatalities occurred. Sixty-one of the fatalities occurred in 36 vessel disasters mainly caused by foundering/capsizing due to stability changes in rough weather and collisions; 39 fatal occupational accidents mainly occurred on the larger inspection obligated trawlers during fishing. In the remaining 14 other fatal accidents, the main causal factors were difficult embarking/disembarking conditions by darkness in foreign ports and alcohol intoxication. In the period 1995-2005, the overall incidence rate was 10 per 10,000 fishermen per year with no down-going trend during that period. The fatal accident rates are still too high, despite the efforts to reduce the risk. Increased focus on regular and repeated safety training for all fishermen and improved safety measures are needed, especially in the underscored areas of sea disasters concerning small vessels and occupational accidents on big vessels. Better registration of time at risk for fishermen is needed to validate the effect of the safety measures.

  18. Non-contact method of search and analysis of pulsating vessels

    NASA Astrophysics Data System (ADS)

    Avtomonov, Yuri N.; Tsoy, Maria O.; Postnov, Dmitry E.

    2018-04-01

    Despite the variety of existing methods of recording the human pulse and a solid history of their development, there is still considerable interest in this topic. The development of new non-contact methods, based on advanced image processing, caused a new wave of interest in this issue. We present a simple but quite effective method for analyzing the mechanical pulsations of blood vessels lying close to the surface of the skin. Our technique is a modification of imaging (or remote) photoplethysmography (i-PPG). We supplemented this method with the addition of a laser light source, which made it possible to use other methods of searching for the proposed pulsation zone. During the testing of the method, several series of experiments were carried out with both artificial oscillating objects as well as with the target signal source (human wrist). The obtained results show that our method allows correct interpretation of complex data. To summarize, we proposed and tested an alternative method for the search and analysis of pulsating vessels.

  19. Recruitment and Retention of Mental Health Workers in Ghana

    PubMed Central

    Jack, Helen; Canavan, Maureen; Ofori-Atta, Angela; Taylor, Lauren; Bradley, Elizabeth

    2013-01-01

    Introduction The lack of trained mental health workers is a primary contributor to the mental health treatment gap worldwide. Despite the great need to recruit and retain mental health workers in low-income countries, little is known about how these workers perceive their jobs and what drives them to work in mental health care. Using qualitative interviews, we aimed to explore factors motivating mental health workers in order to inform interventions to increase recruitment and retention. Methods We conducted 28 in-depth, open-ended interviews with staff in Ghana’s three public psychiatric hospitals. We used the snowballing method to recruit participants and the constant comparative method for qualitative data analysis, with multiple members of the research team participating in data coding to enhance the validity and reliability of the analysis. The use of qualitative methods allowed us to understand the range and depth of motivating and demotivating factors. Results Respondents described many factors that influenced their choice to enter and remain in mental health care. Motivating factors included 1) desire to help patients who are vulnerable and in need, 2) positive day-to-day interactions with patients, 3) intellectual or academic interest in psychiatry or behavior, and 4) good relationships with colleagues. Demotivating factors included 1) lack of resources at the hospital, 2) a rigid supervisory hierarchy, 3) lack of positive or negative feedback on work performance, and 4) few opportunities for career advancement within mental health. Conclusions Because many of the factors are related to relationships, these findings suggest that strengthening the interpersonal and team dynamics may be a critical and relatively low cost way to increase worker motivation. The data also allowed us to highlight key areas for resource allocation to improve both recruitment and retention, including risk pay, adequate tools for patient care, improved hospital work environment

  20. Recruitment and retention of mental health workers in Ghana.

    PubMed

    Jack, Helen; Canavan, Maureen; Ofori-Atta, Angela; Taylor, Lauren; Bradley, Elizabeth

    2013-01-01

    The lack of trained mental health workers is a primary contributor to the mental health treatment gap worldwide. Despite the great need to recruit and retain mental health workers in low-income countries, little is known about how these workers perceive their jobs and what drives them to work in mental health care. Using qualitative interviews, we aimed to explore factors motivating mental health workers in order to inform interventions to increase recruitment and retention. We conducted 28 in-depth, open-ended interviews with staff in Ghana's three public psychiatric hospitals. We used the snowballing method to recruit participants and the constant comparative method for qualitative data analysis, with multiple members of the research team participating in data coding to enhance the validity and reliability of the analysis. The use of qualitative methods allowed us to understand the range and depth of motivating and demotivating factors. Respondents described many factors that influenced their choice to enter and remain in mental health care. Motivating factors included 1) desire to help patients who are vulnerable and in need, 2) positive day-to-day interactions with patients, 3) intellectual or academic interest in psychiatry or behavior, and 4) good relationships with colleagues. Demotivating factors included 1) lack of resources at the hospital, 2) a rigid supervisory hierarchy, 3) lack of positive or negative feedback on work performance, and 4) few opportunities for career advancement within mental health. Because many of the factors are related to relationships, these findings suggest that strengthening the interpersonal and team dynamics may be a critical and relatively low cost way to increase worker motivation. The data also allowed us to highlight key areas for resource allocation to improve both recruitment and retention, including risk pay, adequate tools for patient care, improved hospital work environment, and stigma reduction efforts.

  1. Imprinted Clay Coil Vessels

    ERIC Educational Resources Information Center

    Lohr, Tresa Rae

    2006-01-01

    The author teaches clay vessel construction in the fifth grade, and it is amazing what can be accomplished in one forty-five minute period when the expectations are clarified in the initial lesson. The author introduces clay coil vessels with a discussion of the sources of clay and how clay relates to fifth-grade science curriculum concepts such…

  2. 46 CFR 188.10-49 - Numbered vessel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

  3. 46 CFR 188.10-49 - Numbered vessel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

  4. 46 CFR 188.10-49 - Numbered vessel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

  5. 46 CFR 188.10-49 - Numbered vessel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

  6. 46 CFR 188.10-49 - Numbered vessel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Numbered vessel. 188.10-49 Section 188.10-49 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OCEANOGRAPHIC RESEARCH VESSELS GENERAL PROVISIONS Definition of Terms Used in This Subchapter § 188.10-49 Numbered vessel. This term means a vessel...

  7. Reframing Retention Strategy: A Focus on Profile

    ERIC Educational Resources Information Center

    Kalsbeek, David H.; Zucker, Brian

    2013-01-01

    Over 35 years of retention theory and literature have acknowledged the importance of institutional and student profiles in accounting for cross-sectional differences in retention and completion rates between types of colleges and universities. The first "P" within a 4 Ps framework of student retention--"profile"--recognizes that an institution's…

  8. Toward a Political Explanation of Grade Retention

    ERIC Educational Resources Information Center

    Bali, Valentina A.; Anagnostopoulos, Dorothea; Roberts, Reginald

    2005-01-01

    Policies that mandate in-grade retention of low-performing students have become central components of standards-based reforms across the country. While educational researchers have extensively studied the student-level correlates of retention and the consequences of retention for student achievement, little attention has been focused on…

  9. 46 CFR 173.053 - Sailing school vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Sailing school vessels. 173.053 Section 173.053 Shipping... PERTAINING TO VESSEL USE School Ships § 173.053 Sailing school vessels. (a) In addition to the requirements in §§ 173.054 through 173.063, each sailing school vessel must comply with the provisions of subpart...

  10. 46 CFR 173.053 - Sailing school vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Sailing school vessels. 173.053 Section 173.053 Shipping... PERTAINING TO VESSEL USE School Ships § 173.053 Sailing school vessels. (a) In addition to the requirements in §§ 173.054 through 173.063, each sailing school vessel must comply with the provisions of subpart...

  11. The Influence of Microstructure on Deuterium Retention in Polycrystalline Tungsten

    DOE PAGES

    Garrison, Lauren M.; Meyer, Fred W.; Bannister, Mark E.

    2017-09-18

    The retention of hydrogen isotopes in the plasma-facing materials of a fusion reactor is dependent on the density of trapping sites in the material. One factor that can influence the trapping defects is the surface state of the material before exposure. Mechanically polished, electropolished, and recrystallized tungsten samples were compared by exposing them to 350 eV D + beams with peak fluences of ~1 × 10 24 D +/m 2 at 500 and 740 K at the Multicharged Ion Research Facility (MIRF). At the exposure temperature of 740 K, no significant retention was detected. For material exposed at 500 K,more » significant differences in retention were observed, and the order of increasing retention was recrystallized, electropolished, and mechanically polished. Lastly, the other variable besides surface treatment was the time delay between ion exposure and thermal desorption spectroscopy which also may have impacted the retention measurements if there was out-gassing of the D while samples were in storage before thermal desorption spectroscopy (TDS).« less

  12. The Influence of Microstructure on Deuterium Retention in Polycrystalline Tungsten

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Garrison, Lauren M.; Meyer, Fred W.; Bannister, Mark E.

    The retention of hydrogen isotopes in the plasma-facing materials of a fusion reactor is dependent on the density of trapping sites in the material. One factor that can influence the trapping defects is the surface state of the material before exposure. Mechanically polished, electropolished, and recrystallized tungsten samples were compared by exposing them to 350 eV D + beams with peak fluences of ~1 × 10 24 D +/m 2 at 500 and 740 K at the Multicharged Ion Research Facility (MIRF). At the exposure temperature of 740 K, no significant retention was detected. For material exposed at 500 K,more » significant differences in retention were observed, and the order of increasing retention was recrystallized, electropolished, and mechanically polished. Lastly, the other variable besides surface treatment was the time delay between ion exposure and thermal desorption spectroscopy which also may have impacted the retention measurements if there was out-gassing of the D while samples were in storage before thermal desorption spectroscopy (TDS).« less

  13. High-performance fiber/epoxy composite pressure vessels

    NASA Technical Reports Server (NTRS)

    Chiao, T. T.; Hamstad, M. A.; Jessop, E. S.; Toland, R. H.

    1978-01-01

    Activities described include: (1) determining the applicability of an ultrahigh-strength graphite fiber to composite pressure vessels; (2) defining the fatigue performance of thin-titanium-lined, high-strength graphite/epoxy pressure vessel; (3) selecting epoxy resin systems suitable for filament winding; (4) studying the fatigue life potential of Kevlar 49/epoxy pressure vessels; and (5) developing polymer liners for composite pressure vessels. Kevlar 49/epoxy and graphite fiber/epoxy pressure vessels, 10.2 cm in diameter, some with aluminum liners and some with alternation layers of rubber and polymer were fabricated. To determine liner performance, vessels were subjected to gas permeation tests, fatigue cycling, and burst tests, measuring composite performance, fatigue life, and leak rates. Both the metal and the rubber/polymer liner performed well. Proportionately larger pressure vessels (20.3 and 38 cm in diameter) were made and subjected to the same tests. In these larger vessels, line leakage problems with both liners developed the causes of the leaks were identified and some solutions to such liner problems are recommended.

  14. Veterans’ Perspectives on Interventions to Improve Retention in HIV Care

    PubMed Central

    Kertz, Barbara L.; Cully, Jeffery A.; Stanley, Melinda A.; Davila, Jessica A.; Dang, Bich N.; Rodriguez-Barradas, Maria C.; Giordano, Thomas P.

    2016-01-01

    Poor retention in HIV medical care is associated with increased mortality among patients with HIV/AIDS. Developing new interventions to improve retention in HIV primary care is needed. The Department of Veteran Affairs (VA) is the largest single provider of HIV care in the US. We sought to understand what veterans would want in an intervention to improve retention in VA HIV care. We conducted 18 one-on-one interviews and 15 outpatient focus groups with 46 patients living with HIV infection from the Michael E. DeBakey VAMC (MEDVAMC). Analysis identified three focus areas for improving retention in care: developing an HIV friendly clinic environment, providing mental health and substance use treatment concurrent with HIV care and encouraging peer support from other Veterans with HIV. PMID:26829641

  15. 33 CFR 157.140 - Tank vessel inspections.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Tank vessel inspections. 157.140...) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Inspections § 157.140 Tank vessel inspections. (a) Before...

  16. 40 CFR 63.766 - Storage vessel standards.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 11 2013-07-01 2013-07-01 false Storage vessel standards. 63.766... § 63.766 Storage vessel standards. (a) This section applies to each storage vessel with the potential... storage vessel with the potential for flash emissions (as defined in § 63.761) shall comply with one of...

  17. 40 CFR 63.766 - Storage vessel standards.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Storage vessel standards. 63.766... § 63.766 Storage vessel standards. (a) This section applies to each storage vessel with the potential... storage vessel with the potential for flash emissions (as defined in § 63.761) shall comply with one of...

  18. 40 CFR 63.766 - Storage vessel standards.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 10 2011-07-01 2011-07-01 false Storage vessel standards. 63.766... § 63.766 Storage vessel standards. (a) This section applies to each storage vessel with the potential... storage vessel with the potential for flash emissions (as defined in § 63.761) shall comply with one of...

  19. Environmental Implications of Maritime Vessel Intensification in Arctic Waters

    NASA Astrophysics Data System (ADS)

    Stevenson, T. C.; Banis, D.; Sheard, W.

    2016-12-01

    In 2016, the Arctic experienced some of the warmest monthly temperatures on record. Record high temperatures in the Arctic continue to cause rapid sea ice declines, opening new areas of ocean to commercial exploitation and transportation and causing significant reductions in critical sea ice habitats used by iconic species. Elevated maritime vessel traffic in the Arctic is projected to increase black carbon emissions, encourage the spread of invasive species, increase mammal strikes, intensify conflict with smaller subsistence boats, and heighten oil spill risks. The Arctic Council, an intergovernmental organization concerned with sustainable development and environmental protection, is working with member countries, indigenous participants and other groups on developing networks of marine protected areas within ecologically or biologically important areas. To help inform that process, we analyzed vessel traffic and marine protected area coverage occurring within ecologically or biologically significant areas in the circumpolar Arctic. Our preliminary findings suggest vessel traffic within ecologically or biologically significant areas were highest around Iceland, Norway, Russia and United States but differed by vessel type. The density of fishing vessels occurring within ecologically or biologically important areas were highest near Norway, Iceland, Faroe Islands, parts of Greenland and United States, whereas vessels carrying liquefied natural gas and oil were concentrated near Norway and Russia. The percentage of area covered by marine protected areas within ecologically or biologically significant areas was low, with the exception of places like Wrangel Island, Svalbard, and areas around Greenland. These findings are important because it illustrates ecologically or biologically significant areas in the Arctic are vulnerable to projected vessel traffic intensification and the level of protection afforded by marine protected areas is relatively low.

  20. [Retention and biomechanics of retentive complexes. 3. The Kratochvil school and current retentive complexes].

    PubMed

    Enrique Fernández, M; Jacques Grimonster, L

    1989-04-01

    The authors analyse the biomechanical bases of the Kratochvil "retentive complex" and show how they have induced the nowadays north-american propositions (RPI & RPA). They compare them to the european ones (Nally-Martinet).

  1. Soil Water Retention Curve

    NASA Astrophysics Data System (ADS)

    Johnson, L. E.; Kim, J.; Cifelli, R.; Chandra, C. V.

    2016-12-01

    Potential water retention, S, is one of parameters commonly used in hydrologic modeling for soil moisture accounting. Physically, S indicates total amount of water which can be stored in soil and is expressed in units of depth. S can be represented as a change of soil moisture content and in this context is commonly used to estimate direct runoff, especially in the Soil Conservation Service (SCS) curve number (CN) method. Generally, the lumped and the distributed hydrologic models can easily use the SCS-CN method to estimate direct runoff. Changes in potential water retention have been used in previous SCS-CN studies; however, these studies have focused on long-term hydrologic simulations where S is allowed to vary at the daily time scale. While useful for hydrologic events that span multiple days, the resolution is too coarse for short-term applications such as flash flood events where S may not recover its full potential. In this study, a new method for estimating a time-variable potential water retention at hourly time-scales is presented. The methodology is applied for the Napa River basin, California. The streamflow gage at St Helena, located in the upper reaches of the basin, is used as the control gage site to evaluate the model performance as it is has minimal influences by reservoirs and diversions. Rainfall events from 2011 to 2012 are used for estimating the event-based SCS CN to transfer to S. As a result, we have derived the potential water retention curve and it is classified into three sections depending on the relative change in S. The first is a negative slope section arising from the difference in the rate of moving water through the soil column, the second is a zero change section representing the initial recovery the potential water retention, and the third is a positive change section representing the full recovery of the potential water retention. Also, we found that the soil water moving has traffic jam within 24 hours after finished first

  2. A Narrative Inquiry of Teacher Retention in Supplemental Education

    ERIC Educational Resources Information Center

    Saint, April

    2012-01-01

    Teacher retention in supplemental education, or for-profit, center-based tutoring, is a concern. As yet, no studies in the past 20 years have examined teacher retention in supplemental education. The importance of this research study was to give voice to supplemental educators' experiences in center-based tutoring through narrative inquiry. The…

  3. Reframing Retention Strategy: A Focus on Progress

    ERIC Educational Resources Information Center

    Spittle, Brian

    2013-01-01

    Few words have dominated the vocabulary of college retention as has the word "persistence." Many institutions still struggle to engage faculty and administrators in building campuswide retention efforts, to find the organizational levers that translate the abstractions and complexities of retention theory into scalable and durable initiatives, and…

  4. 46 CFR 308.600 - Records retention requirement.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

  5. 46 CFR 308.600 - Records retention requirement.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 8 2012-10-01 2012-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

  6. 46 CFR 308.600 - Records retention requirement.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

  7. 46 CFR 308.600 - Records retention requirement.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 8 2014-10-01 2014-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

  8. 46 CFR 308.600 - Records retention requirement.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Records retention requirement. 308.600 Section 308.600 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION EMERGENCY OPERATIONS WAR RISK INSURANCE Records Retention § 308.600 Records retention requirement. The records specified in §§ 308.8, 308.517, and...

  9. Persistence-Retention. Snapshot™ Report, Spring 2015

    ERIC Educational Resources Information Center

    National Student Clearinghouse, 2015

    2015-01-01

    This Snapshot Report offers information on student persistence and retention rates for 2009-2013. It offers data on the following: (1) First-Year Persistence and Retention Rates for Students Who Start College at Four-Year Private Nonprofit Institutions; (2) First-Year Persistence and Retention Rates for Students Who Start College at Four-Year…

  10. Detergent-enzymatic decellularization of swine blood vessels: insight on mechanical properties for vascular tissue engineering.

    PubMed

    Pellegata, Alessandro F; Asnaghi, M Adelaide; Stefani, Ilaria; Maestroni, Anna; Maestroni, Silvia; Dominioni, Tommaso; Zonta, Sandro; Zerbini, Gianpaolo; Mantero, Sara

    2013-01-01

    Small caliber vessels substitutes still remain an unmet clinical need; few autologous substitutes are available, while synthetic grafts show insufficient patency in the long term. Decellularization is the complete removal of all cellular and nuclear matters from a tissue while leaving a preserved extracellular matrix representing a promising tool for the generation of acellular scaffolds for tissue engineering, already used for various tissues with positive outcomes. The aim of this work is to investigate the effect of a detergent-enzymatic decellularization protocol on swine arteries in terms of cell removal, extracellular matrix preservation, and mechanical properties. Furthermore, the effect of storage at -80°C on the mechanical properties of the tissue is evaluated. Swine arteries were harvested, frozen, and decellularized; histological analysis revealed complete cell removal and preserved extracellular matrix. Furthermore, the residual DNA content in decellularized tissues was far low compared to native one. Mechanical testings were performed on native, defrozen, and decellularized tissues; no statistically significant differences were reported for Young's modulus, ultimate stress, compliance, burst pressure, and suture retention strength, while ultimate strain and stress relaxation of decellularized vessels were significantly different from the native ones. Considering the overall results, the process was confirmed to be suitable for the generation of acellular scaffolds for vascular tissue engineering.

  11. Suspended solids and nutrient retention in rural constructed wetlands in cold climate

    NASA Astrophysics Data System (ADS)

    Koskiaho, Jari; Siimekselä, Tiina; Puustinen, Markku

    2016-04-01

    Three constructed wetlands (CWs), two located in southern and one in central Finland, were monitored during 2013-2015. The southern CWs Hovi (0.6 ha wet area) and Rantamo-Seitteli (24 ha wet area) were monitored continuously by s::can nitro::lyser (www.s-can.at) sensors. On average 10 pairs (inflow and outflow) of water samples were annually taken in the two southern CWs and 20 pairs in the northernmost Tarvaala CW (wet area 1.4 ha). In Tarvaala, a portable, continuously measuring Micromac 1000 -phosphate analyzer (www.systea.it) was also tested at the CW outlet in 2015. The CWs differed in their size, dimensioning (CW-to-catchment area ratio) and in the characteristics of their upstream catchments. The Hovi CW has 5.0% CW-to-catchment area ratio and 100% agricultural land use in its clayey catchment. The corresponding percentages were for the Rantamo-Seitteli CW (clayey catchment) 1.3% and 42%, and for the Tarvaala CW (coarse soil type in the catchment) 1.0% and 16%. The average annual total suspended solids (TSS) retentions in Hovi, Rantamo-Seitteli and Tarvaala CWs were 79%, 6% and 50%, respectively. The average annual total phosphorus (TP) retentions were 61% at Hovi, 22% at Rantamo-Seitteli and 23% at Tarvaala. The unexpectedly high TSS and TP retentions at Tarvaala were probably due to the coarse soil type with more readily settling particles than in two other CWs. In Hovi and Rantamo-Seitteli CWs also dissolved reactive phosphorus (DRP) was measured. The DRP retentions (83% at Hovi and 27% at Rantamo-Seitteli) were higher than those of TP, which was probably due to the high contents of P-binding Al- and Fe-oxides in the soil of these two CWs. In the Hovi CW, vivid biological activity (abundant vegetation, algae and microbes) might also have played a role. The average annual total nitrogen (TN) retentions in Hovi and Rantamo-Seitteli CWs were 66% and 14%, respectively. At Tarvaala, TN retention varied annually so that no net retention over the whole period

  12. 33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... exhibit: (1) Sidelights; and (2) A sternlight. (b) Sailing vessels of less than 20 meters in length. In a... with the combined lantern permitted by paragraph (b) of this Rule. (d) Sailing vessels of less than 7... practicable, exhibit the lights prescribed in paragraph (a) or (b) of this Rule, but if she does not, she...

  13. 33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... exhibit: (1) Sidelights; and (2) A sternlight. (b) Sailing vessels of less than 20 meters in length. In a... with the combined lantern permitted by paragraph (b) of this Rule. (d) Sailing vessels of less than 7... practicable, exhibit the lights prescribed in paragraph (a) or (b) of this Rule, but if she does not, she...

  14. 33 CFR 83.25 - Sailing vessels underway and vessels under oars (Rule 25).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... exhibit: (1) Sidelights; and (2) A sternlight. (b) Sailing vessels of less than 20 meters in length. In a... with the combined lantern permitted by paragraph (b) of this Rule. (d) Sailing vessels of less than 7... practicable, exhibit the lights prescribed in paragraph (a) or (b) of this Rule, but if she does not, she...

  15. Composite Overwrapped Pressure Vessels, A Primer

    NASA Technical Reports Server (NTRS)

    McLaughlan, Pat B.; Forth, Scott C.; Grimes-Ledesma, Lorie R.

    2011-01-01

    Due to the extensive amount of detailed information that has been published on composite overwrapped pressure vessels (COPVs), this document has been written to serve as a primer for those who desire an elementary knowledge of COPVs and the factors affecting composite safety. In this application, the word "composite" simply refers to a matrix of continuous fibers contained within a resin and wrapped over a pressure barrier to form a vessel for gas or liquid containment. COPVs are currently used at NASA to contain high pressure fluids in propulsion, science experiments, and life support applications. They have a significant weight advantage over all metal vessels but require unique design, manufacturing, and test requirements. COPVs also involve a much more complex mechanical understanding due to the interplay between the composite overwrap and the inner liner. A metallic liner is typically used in a COPV as a fluid permeation barrier. The liner design concepts and requirements have been borrowed from all-metal vessels. However, application of metallic vessel design standards to a very thin liner is not straightforward. Different failure modes exist for COPVs than for all-metal vessels, and understanding of these failure modes is at a much more rudimentary level than for metal vessels.

  16. Assessing Retention in Online Learning: An Administrative Perspective

    ERIC Educational Resources Information Center

    Boston, Wallace E.; Ice, Phil

    2011-01-01

    As the growth of online programs continues to rapidly accelerate, concern over the retention of the online learner is increasing. Educational administrators at institutions offering online courses, those fully online or brick and mortars, are eager to promote student achievement. Retention is critically important, not just for student success, but…

  17. 46 CFR 3.05-3 - Oceanographic research vessel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Oceanographic research vessel. 3.05-3 Section 3.05-3... OCEANOGRAPHIC RESEARCH VESSELS Definition of Terms Used in This Part § 3.05-3 Oceanographic research vessel. “An oceanographic research vessel is a vessel which the U.S. Coast Guard finds is employed exclusively in one or...

  18. 46 CFR 3.05-3 - Oceanographic research vessel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Oceanographic research vessel. 3.05-3 Section 3.05-3... OCEANOGRAPHIC RESEARCH VESSELS Definition of Terms Used in This Part § 3.05-3 Oceanographic research vessel. “An oceanographic research vessel is a vessel which the U.S. Coast Guard finds is employed exclusively in one or...

  19. 46 CFR 3.05-3 - Oceanographic research vessel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Oceanographic research vessel. 3.05-3 Section 3.05-3... OCEANOGRAPHIC RESEARCH VESSELS Definition of Terms Used in This Part § 3.05-3 Oceanographic research vessel. “An oceanographic research vessel is a vessel which the U.S. Coast Guard finds is employed exclusively in one or...

  20. 46 CFR 3.05-3 - Oceanographic research vessel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Oceanographic research vessel. 3.05-3 Section 3.05-3... OCEANOGRAPHIC RESEARCH VESSELS Definition of Terms Used in This Part § 3.05-3 Oceanographic research vessel. “An oceanographic research vessel is a vessel which the U.S. Coast Guard finds is employed exclusively in one or...

  1. 46 CFR 3.05-3 - Oceanographic research vessel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Oceanographic research vessel. 3.05-3 Section 3.05-3... OCEANOGRAPHIC RESEARCH VESSELS Definition of Terms Used in This Part § 3.05-3 Oceanographic research vessel. “An oceanographic research vessel is a vessel which the U.S. Coast Guard finds is employed exclusively in one or...

  2. The Successful Mobilization of a Campus Community for Student Retention. Report of the University Retention Steering Committee.

    ERIC Educational Resources Information Center

    Eastern Michigan Univ., Ypsilanti.

    Components of a student retention program at Eastern Michigan University are examined; for each effort to improve retention, project objectives and design, results, and recommendations are presented. Retention initiatives, decided upon as a result of a campus-wide mobilization of effort, include: a student-focused orientation system, a fast track…

  3. 46 CFR 105.10-25 - Commercial fishing vessel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

  4. 46 CFR 105.10-25 - Commercial fishing vessel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

  5. 46 CFR 105.10-25 - Commercial fishing vessel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

  6. 46 CFR 105.10-25 - Commercial fishing vessel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

  7. 46 CFR 105.10-25 - Commercial fishing vessel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Commercial fishing vessel. 105.10-25 Section 105.10-25... COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Definition of Terms Used in This Part § 105.10-25 Commercial fishing vessel. (a) The term commercial fishing vessel includes fishing vessels, cannery tenders...

  8. Retinal vessel segmentation on SLO image

    PubMed Central

    Xu, Juan; Ishikawa, Hiroshi; Wollstein, Gadi; Schuman, Joel S.

    2010-01-01

    A scanning laser ophthalmoscopy (SLO) image, taken from optical coherence tomography (OCT), usually has lower global/local contrast and more noise compared to the traditional retinal photograph, which makes the vessel segmentation challenging work. A hybrid algorithm is proposed to efficiently solve these problems by fusing several designed methods, taking the advantages of each method and reducing the error measurements. The algorithm has several steps consisting of image preprocessing, thresholding probe and weighted fusing. Four different methods are first designed to transform the SLO image into feature response images by taking different combinations of matched filter, contrast enhancement and mathematical morphology operators. A thresholding probe algorithm is then applied on those response images to obtain four vessel maps. Weighted majority opinion is used to fuse these vessel maps and generate a final vessel map. The experimental results showed that the proposed hybrid algorithm could successfully segment the blood vessels on SLO images, by detecting the major and small vessels and suppressing the noises. The algorithm showed substantial potential in various clinical applications. The use of this method can be also extended to medical image registration based on blood vessel location. PMID:19163149

  9. Does Vessel Noise Affect Oyster Toadfish Calling Rates?

    PubMed

    Luczkovich, Joseph J; Krahforst, Cecilia S; Hoppe, Harry; Sprague, Mark W

    2016-01-01

    The question we addressed in this study is whether oyster toadfish respond to vessel disturbances by calling less when vessels with lower frequency spectra are present in a sound recording and afterward. Long-term data recorders were deployed at the Neuse (high vessel-noise site) and Pamlico (low vessel-noise site) Rivers. There were many fewer toadfish detections at the high vessel-noise site than the low-noise station. Calling rates were lower in the high-boat traffic area, suggesting that toadfish cannot call over loud vessel noise, reducing the overall calling rate, and may have to call more often when vessels are not present.

  10. 50 CFR 622.6 - Vessel identification.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... been issued to fish with a sea bass pot, as required under § 622.170(a)(1); a vessel in the commercial Caribbean reef fish fishery fishing with traps; and a vessel in the Caribbean spiny lobster fishery. Color... the fishing vessel, its rigging, fishing gear, or any other material on board obstructs the view of...

  11. 50 CFR 622.6 - Vessel identification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... been issued to fish with a sea bass pot, as required under § 622.170(a)(1); a vessel in the commercial Caribbean reef fish fishery fishing with traps; and a vessel in the Caribbean spiny lobster fishery. Color... the fishing vessel, its rigging, fishing gear, or any other material on board obstructs the view of...

  12. Effects of air vessel on water hammer in high-head pumping station

    NASA Astrophysics Data System (ADS)

    Wang, L.; Wang, F. J.; Zou, Z. C.; Li, X. N.; Zhang, J. C.

    2013-12-01

    Effects of air vessel on water hammer process in a pumping station with high-head were analyzed by using the characteristics method. The results show that the air vessel volume is the key parameter that determines the protective effect on water hammer pressure. The maximum pressure in the system declines with increasing air vessel volume. For a fixed volume of air vessel, the shape of air vessel and mounting style, such as horizontal or vertical mounting, have little effect on the water hammer. In order to obtain good protection effects, the position of air vessel should be close to the outlet of the pump. Generally, once the volume of air vessel is guaranteed, the water hammer of a entire pipeline is effectively controlled.

  13. Electrospun Polycaprolactone Scaffolds for Small-Diameter Tissue Engineered Blood Vessels

    NASA Astrophysics Data System (ADS)

    Lee, Carol Hsiu-Yueh

    Cardiovascular disease is the leading cause of death in the United States with many patients requiring coronary artery bypass grafting. The current standard is using autografts such as the saphenous vein or intimal mammary artery, however creating a synthetic graft could eliminate this painful and inconvenient procedure. Large diameter grafts have long been established with materials such as DacronRTM and TeflonRTM, however these materials have not proved successful in small-diameter (< 6 mm) grafts where thrombosis and intimal hyperplasia are common in graft failure. With the use of a synthetic biodegradable polymer (polycaprolactone) we utilize our expertise in electrospinning and femtosecond laser ablation to create a novel tri-layered tissue engineered blood vessel containing microchannels. The benefits of creating a tri-layer is to mimic native arteries that contain an endothelium to prevent thrombosis in the inner layer, aligned smooth muscle cells in the middle to control vasodilation and constriction, and a mechanically robust outer layer. The following work evaluates the mechanical properties of such a graft (tensile, fatigue, burst pressure, and suture retention strength), the ability to rapidly align cells in laser ablated microchannels in PCL scaffolds, and the biological integration (co-culture of endothelial and smooth muscle cells) with electrospun PCL scaffolds. The conclusions from this work establish that the electrospun tri-layers provide adequate mechanical strength as a tissue engineered blood vessel, that laser ablated microchannels are able to contain the smooth muscle cells, and that cells are able to adhere to PCL fibers. However, future work includes adjusting microchannel dimensions to properly align smooth muscle cells along with perfect co-cultures of endothelial and smooth muscle cells on the electrospun tri-layer.

  14. The Employment Retention and Advancement Project Early Results from Four Sites

    ERIC Educational Resources Information Center

    Bloom, Dan; Hendra, Richard; Martinson, Karin; Scrivener, Susan

    2005-01-01

    Millions of welfare recipients have entered the labor force in the past decade, but surveys show that many remain in unstable, low-paying jobs that offer few opportunities for advancement. This report presents early evidence on the effectiveness of four diverse programs designed to help current or former welfare recipients work more steadily and…

  15. 20 CFR 655.1319 - Document retention requirements.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Document retention requirements. 655.1319... Employment in the United States (H-2A Workers) § 655.1319 Document retention requirements. (a) Entities... retention. Records and documents must be retained for a period of 3 years from the date of certification of...

  16. phosphorus retention data and metadata

    EPA Pesticide Factsheets

    phosphorus retention in wetlands data and metadataThis dataset is associated with the following publication:Lane , C., and B. Autrey. Phosphorus retention of forested and emergent marsh depressional wetlands in differing land uses in Florida, USA. Wetlands Ecology and Management. Springer Science and Business Media B.V;Formerly Kluwer Academic Publishers B.V., GERMANY, 24(1): 45-60, (2016).

  17. Reactor vessel annealing system

    DOEpatents

    Miller, Phillip E.; Katz, Leonoard R.; Nath, Raymond J.; Blaushild, Ronald M.; Tatch, Michael D.; Kordalski, Frank J.; Wykstra, Donald T.; Kavalkovich, William M.

    1991-01-01

    A system for annealing a vessel (14) in situ by heating the vessel (14) to a defined temperature, composed of: an electrically operated heater assembly (10) insertable into the vessel (14) for heating the vessel (14) to the defined temperature; temperature monitoring components positioned relative to the heater assembly (10) for monitoring the temperature of the vessel (14); a controllable electric power supply unit (32-60) for supplying electric power required by the heater assembly (10); a control unit (80-86) for controlling the power supplied by the power supply unit (32-60); a first vehicle (2) containing the power supply unit (32-60); a second vehicle (4) containing the control unit (80-86); power conductors (18,22) connectable between the power supply unit (32-60) and the heater unit (10) for delivering the power supplied by the power supply unit (32-60) to the heater assembly (10); signal conductors (20,24) connectable between the temperature monitoring components and the control unit (80-86) for delivering temperature indicating signals from the temperature monitoring components to the control unit (80-86); and control conductors (8) connectable between the control unit (80-86) and the power supply unit (32-60) for delivering to the power supply unit (32-60) control signals for controlling the level of power supplied by the power supply unit (32-60) to the heater assembly (10).

  18. Grade-Level Retention in Texas Public Schools, 2015-16

    ERIC Educational Resources Information Center

    Texas Education Agency, 2017

    2017-01-01

    This annual report provides information for the 2015-16 school year on grade-level retention in the Texas public school system. Data on retention are provided by student characteristics, including grade level; race/ethnicity; gender; degree of English proficiency; and economic, at-risk, immigrant, migrant, and overage statuses. Data also are…

  19. Beyond Welfare-to-Work: Helping Low-Income Workers Maintain Their Jobs and Advance in the Workforce. Paper #1: Demand-Led Retention.

    ERIC Educational Resources Information Center

    Freeman, Jennifer; Taylor, Judith Combes

    This document is the first in a series of two reports on demand-led strategies to support welfare-to-work clients. The authors believe employment retention programs that demonstrate they can meet the needs of employers for effective employees follow a demand-led approach, which has the potential to expand the opportunities available to welfare…

  20. Retention of Emergency Care Knowledge.

    ERIC Educational Resources Information Center

    Burckes, Mardie E.; Shao, Kung Ping Pam

    1984-01-01

    Data on the emergency care knowledge of college students were measured by a pretest, posttest, and retention test. A high relationship was found between students' posttest scores and retention test scores. Findings are discussed. (Author/DF)

  1. 33 CFR 151.1512 - Vessel safety.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Vessel safety. 151.1512 Section... River § 151.1512 Vessel safety. Nothing in this subpart relieves the master of the responsibility for ensuring the safety and stability of the vessel or the safety of the crew and passengers, or any other...

  2. 33 CFR 151.1512 - Vessel safety.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Vessel safety. 151.1512 Section... River § 151.1512 Vessel safety. Nothing in this subpart relieves the master of the responsibility for ensuring the safety and stability of the vessel or the safety of the crew and passengers, or any other...

  3. 46 CFR 4.03-40 - Public vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... INVESTIGATIONS Definitions § 4.03-40 Public vessels. Public vessel means a vessel that— (a) Is owned, or demise... Department (except a vessel operated by the Coast Guard or Saint Lawrence Seaway Development Corporation...

  4. Automated retinal vessel type classification in color fundus images

    NASA Astrophysics Data System (ADS)

    Yu, H.; Barriga, S.; Agurto, C.; Nemeth, S.; Bauman, W.; Soliz, P.

    2013-02-01

    Automated retinal vessel type classification is an essential first step toward machine-based quantitative measurement of various vessel topological parameters and identifying vessel abnormalities and alternations in cardiovascular disease risk analysis. This paper presents a new and accurate automatic artery and vein classification method developed for arteriolar-to-venular width ratio (AVR) and artery and vein tortuosity measurements in regions of interest (ROI) of 1.5 and 2.5 optic disc diameters from the disc center, respectively. This method includes illumination normalization, automatic optic disc detection and retinal vessel segmentation, feature extraction, and a partial least squares (PLS) classification. Normalized multi-color information, color variation, and multi-scale morphological features are extracted on each vessel segment. We trained the algorithm on a set of 51 color fundus images using manually marked arteries and veins. We tested the proposed method in a previously unseen test data set consisting of 42 images. We obtained an area under the ROC curve (AUC) of 93.7% in the ROI of AVR measurement and 91.5% of AUC in the ROI of tortuosity measurement. The proposed AV classification method has the potential to assist automatic cardiovascular disease early detection and risk analysis.

  5. Recruitment and retention of rural African Americans in diabetes research: lessons learned.

    PubMed

    Loftin, Wanda Anderson; Barnett, Steven K; Bunn, Peggy Summers; Sullivan, Patra

    2005-01-01

    The purpose of this article was to describe lessons learned about recruitment and retention of rural African Americans from published literature, the authors' research, and research experience. Two rural, community-based research studies with African Americans with diabetes are used to illustrate different issues and strategies in recruitment and retention. Relevant MEDLINE articles and clinical studies were reviewed, and the design, implementation, and results of the 2 community-based studies were evaluated. Information from the literature, research results, and sample selection, participation, and attrition experiences were synthesized to determine effective approaches for recruitment and retention. Research funding, design, and implementation; recruitment methods; culturally competent approaches; caring, trusting provider-patient relationships; incentives; follow-up; and factors in the rural environment emerged as important issues influencing recruitment and retention. Recruitment and retention of African Americans in rural diabetes research is a significant challenge, and adequate funding should be sought early in the research process. Culturally competent approaches; caring, trusting relationships; incentives; and follow-up are important concepts in successful recruitment, participation, and retention of African Americans. The lessons learned may be applicable to the more widespread issue of recruitment and retention of rural African Americans in diabetes education programs.

  6. Strategies for improving employee retention.

    PubMed

    Verlander, Edward G; Evans, Martin R

    2007-03-28

    This article proposes a solution to the perennial problem of talent retention in the clinical laboratory. It includes the presentation of 12 strategies that may be used to significantly improve institutional identity formation and establishment of the psychological contract that employees form with laboratory management. Identity formation and psychological contracting are deemed as essential in helping reduce employee turnover and increase retention. The 12 conversational strategies may be used as a set of best practices for all employees, but most importantly for new employees, and should be implemented at the critical moment when employees first join the laboratory. This time is referred to as "retention on-boarding"--the period of induction and laboratory orientation. Retention on-boarding involves a dialogue between employees and management that is focused on the psychological, practical, cultural, and political dimensions of the laboratory. It is placed in the context of the modern clinical laboratory, which is faced with employing and managing Generation X knowledge workers. Specific topics and broad content areas of those conversations are outlined.

  7. The 'rural pipeline' and retention of rural health professionals in Europe's northern peripheries.

    PubMed

    Carson, Dean B; Schoo, Adrian; Berggren, Peter

    2015-12-01

    The major advance in informing rural workforce policy internationally over the past 25 years has been the recognition of the importance of the 'rural pipeline'. The rural pipeline suggests that people with 'rural origin' (who spent some childhood years in rural areas) and/or 'rural exposure' (who do part of their professional training in rural areas) are more likely to select rural work locations. What is not known is whether the rural pipeline also increases the length of time professionals spend in rural practice throughout their careers. This paper analyses data from a survey of rural health professionals in six countries in the northern periphery of Europe in 2013 to examine the relationship between rural origin and rural exposure and the intention to remain in the current rural job or to preference rural jobs in future. Results are compared between countries, between different types of rural areas (based on accessibility to urban centres), different occupations and workers at different stages of their careers. The research concludes that overall the pipeline does impact on retention, and that both rural origin and rural exposure make a contribution. However, the relationship is not strong in all contexts, and health workforce policy should recognise that retention may in some cases be improved by recruiting beyond the pipeline. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Adaptation of mesenteric lymphatic vessels to prolonged changes in transmural pressure.

    PubMed

    Dongaonkar, R M; Nguyen, T L; Quick, C M; Hardy, J; Laine, G A; Wilson, E; Stewart, R H

    2013-07-15

    In vitro studies have revealed that acute increases in transmural pressure increase lymphatic vessel contractile function. However, adaptive responses to prolonged changes in transmural pressure in vivo have not been reported. Therefore, we developed a novel bovine mesenteric lymphatic partial constriction model to test the hypothesis that lymphatic vessels exposed to higher transmural pressures adapt functionally to become stronger pumps than vessels exposed to lower transmural pressures. Postnodal mesenteric lymphatic vessels were partially constricted for 3 days. On postoperative day 3, constricted vessels were isolated, and divided into upstream (UP) and downstream (DN) segment groups, and instrumented in an isolated bath. Although there were no differences between the passive diameters of the two groups, both diastolic diameter and systolic diameter were significantly larger in the UP group than in the DN group. The pump index of the UP group was also higher than that in the DN group. In conclusion, this is the first work to report how lymphatic vessels adapt to prolonged changes in transmural pressure in vivo. Our results suggest that vessel segments upstream of the constriction adapt to become both better fluid conduits and lymphatic pumps than downstream segments.

  9. How to improve patient retention in an antiretroviral treatment program in Ethiopia: a mixed-methods study

    PubMed Central

    2014-01-01

    Background Patient retention, defined as continuous engagement of patients in care, is one of the crucial indicators for monitoring and evaluating the performance of antiretroviral treatment (ART) programs. It has been identified that suboptimal patient retention in care is one of the challenges of ART programs in many settings. ART programs have, therefore, been striving hard to identify and implement interventions that improve their suboptimal levels of retention. The objective of this study was to develop a framework for improving patient retention in care based on interventions implemented in health facilities that have achieved higher levels of retention in care. Methods A mixed-methods study, based on the positive deviance approach, was conducted in Ethiopia in 2011/12. Quantitative data were collected to estimate and compare the levels of retention in care in nine health facilities. Key informant interviews and focus group discussions were conducted to identify a package of interventions implemented in the health facilities with relatively higher or improving levels of retention. Results Retention in care in the Ethiopian ART program was found to be variable across health facilities. Among hospitals, the poorest performer had 0.46 (0.35, 0.60) times less retention than the reference; among health centers, the poorest performers had 0.44 (0.28, 0.70) times less retention than the reference. Health facilities with higher and improving patient retention were found to implement a comprehensive package of interventions: (1) retention promoting activities by health facilities, (2) retention promoting activities by community-based organizations, (3) coordination of these activities by case manager(s), and (4) patient information systems by data clerk(s). On the contrary, such interventions were either poorly implemented or did not exist in health facilities with lower retention in care. A framework to improve retention in care was developed based on the evidence

  10. Trend of change in retentive force for bar attachments with different materials.

    PubMed

    Saito, Marie; Kanazawa, Manabu; Takahashi, Hidekazu; Uo, Motohiro; Minakuchi, Shunsuke

    2014-12-01

    Attachment wear can decrease the retentive force of 2-implant overdentures (2-IODs). The purpose of this in vitro study was to investigate the trend of change in retentive force for 6 different bar attachments during dislodgement. Round and Dolder bars were made of platinum-added gold alloy (PGA), cobalt chromium alloy (Co-Cr), and commercially pure titanium grade IV (Ti). Clips were made of PGA. Retentive force was measured during 7200 dislodging cycles. Simple linear regression analysis was performed in order to investigate the relationship between number of cycles and retentive force (P<.05). Subsequently, wear debris was analyzed, and the surface of the attachments was observed. The retentive force of the Co-Cr round bar attachment (CoCr-R) increased from 57.5 N to 68.3 N and the Ti round bar attachment (Ti-R) from 54.8 N to 59.7 N. However, the retentive force of the PGA round bar attachment (PGA-R) decreased from 69.3 N to 64.0 N. A positive relationship was found between the number of cycles and the retentive force of both CoCr-R and Ti-R. The composition of the wear debris was almost the same as for PGA. For the Dolder bar attachment, no changes were seen in retentive force (between 7.0 N to 12.0 N). For the round bar attachment, the PGA clip and PGA bar showed wear. The retentive force of PGA-R slightly decreased. The retentive force of CoCr-R and Ti-R tended to increase. For the Dolder bar attachment, all 3 types of bar attachment showed no wear. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  11. 47 CFR 3.53 - FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s).

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s). 3.53 Section 3.53 Telecommunication FEDERAL COMMUNICATIONS... telecommunications service to U.S. registered vessel(s). An accounting authority must inform the FCC immediately...

  12. 47 CFR 3.53 - FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s).

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s). 3.53 Section 3.53 Telecommunication FEDERAL COMMUNICATIONS... telecommunications service to U.S. registered vessel(s). An accounting authority must inform the FCC immediately...

  13. 47 CFR 3.53 - FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s).

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 1 2012-10-01 2012-10-01 false FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s). 3.53 Section 3.53 Telecommunication FEDERAL COMMUNICATIONS... telecommunications service to U.S. registered vessel(s). An accounting authority must inform the FCC immediately...

  14. 47 CFR 3.53 - FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s).

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s). 3.53 Section 3.53 Telecommunication FEDERAL COMMUNICATIONS... telecommunications service to U.S. registered vessel(s). An accounting authority must inform the FCC immediately...

  15. 47 CFR 3.53 - FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false FCC notification of refusal to provide telecommunications service to U.S. registered vessel(s). 3.53 Section 3.53 Telecommunication FEDERAL COMMUNICATIONS... telecommunications service to U.S. registered vessel(s). An accounting authority must inform the FCC immediately...

  16. Learning and Retention Using Virtual Reality in a Decontamination Simulation.

    PubMed

    Smith, Sherrill J; Farra, Sharon; Ulrich, Deborah L; Hodgson, Eric; Nicely, Stephanie; Matcham, William

    The purpose of this study was to examine the longitudinal effects of virtual reality simulation (VRS) on learning outcomes and retention. Disaster preparation for health care professionals is seriously inadequate. VRS offers an opportunity to practice within a realistic and safe environment, but little is known about learning and retention using this pedagogy. A quasiexperimental design was used to examine the use of VRS with baccalaureate nursing students in two different nursing programs in terms of the skill of decontamination. Results indicate that VRS is at least as good as traditional methods and is superior in some cases for retention of knowledge and performance of skills. VRS may provide a valuable option for promoting skill development and retention. More research is needed to determine how to prepare nurses for skills that may not be required until months or even years after initial introduction.

  17. Fatal hemoptysis in patients with advanced esophageal cancer treated with apatinib

    PubMed Central

    Wang, Wei; Zhang, Lin; Xie, Yan; Zhen, Tianchang; Su, Gongzhang; Zang, Qi

    2018-01-01

    Targeted therapy is commonly used for treating advanced malignant tumors. Compared with cytotoxic drugs, targeted drugs have the characteristics of good curative results, less adverse effects, and convenient oral administration. Hence, they are especially suitable for patients with cancer who are not able to tolerate chemotherapy. Anti-angiogenic therapy can achieve the objective by inhibiting the formation of new blood vessels in tumors. Apatinib is a novel tyrosine kinase inhibitor targeting the intracellular domain of vascular endothelial growth factor receptor-2. It has been proven to be effective and safe in treating patients with gastric carcinoma and gastroesophageal junction carcinoma. So far, no reports are available on the treatment of esophageal cancer with apatinib. Two patients with advanced esophageal cancer were treated with oral apatinib because of their poor physical condition. After treatment, the dyspnea symptoms disappeared and quality of life significantly improved. Chest computed tomography showed massive necrosis of tumor tissues in each patient. The tumors significantly reduced and a cavity was formed locally in each patient. However, both patients died of massive hemoptysis, probably due to the rupture of the bronchial artery eroded by tumors. The results indicated that apatinib was effective in treating some patients with advanced esophageal cancer, and adverse effects were controllable. However, doctors should choose appropriate candidates according to apatinib’s indications. In addition, the use of apatinib should be carefully controlled for patients with esophageal cancer, especially in those with large vessels and trachea or bronchus eroded by tumor, so as to avoid or reduce the occurrence of fatal hemorrhage. PMID:29765235

  18. Fatal hemoptysis in patients with advanced esophageal cancer treated with apatinib.

    PubMed

    Wang, Wei; Zhang, Lin; Xie, Yan; Zhen, Tianchang; Su, Gongzhang; Zang, Qi

    2018-01-01

    Targeted therapy is commonly used for treating advanced malignant tumors. Compared with cytotoxic drugs, targeted drugs have the characteristics of good curative results, less adverse effects, and convenient oral administration. Hence, they are especially suitable for patients with cancer who are not able to tolerate chemotherapy. Anti-angiogenic therapy can achieve the objective by inhibiting the formation of new blood vessels in tumors. Apatinib is a novel tyrosine kinase inhibitor targeting the intracellular domain of vascular endothelial growth factor receptor-2. It has been proven to be effective and safe in treating patients with gastric carcinoma and gastroesophageal junction carcinoma. So far, no reports are available on the treatment of esophageal cancer with apatinib. Two patients with advanced esophageal cancer were treated with oral apatinib because of their poor physical condition. After treatment, the dyspnea symptoms disappeared and quality of life significantly improved. Chest computed tomography showed massive necrosis of tumor tissues in each patient. The tumors significantly reduced and a cavity was formed locally in each patient. However, both patients died of massive hemoptysis, probably due to the rupture of the bronchial artery eroded by tumors. The results indicated that apatinib was effective in treating some patients with advanced esophageal cancer, and adverse effects were controllable. However, doctors should choose appropriate candidates according to apatinib's indications. In addition, the use of apatinib should be carefully controlled for patients with esophageal cancer, especially in those with large vessels and trachea or bronchus eroded by tumor, so as to avoid or reduce the occurrence of fatal hemorrhage.

  19. Stemming the Revolving Door: Teacher Retention and Attrition in Arctic Alaska Schools

    ERIC Educational Resources Information Center

    Kaden, Ute; Patterson, Philip P.; Healy, Joanne; Adams, Barbara L.

    2016-01-01

    Limited research is available concerning teacher retention and teacher attrition in Arctic Alaska. This paper reports survey research findings, which identify factors related to teacher retention and attrition in Alaskan Arctic Native communities. Teacher retention rates (2009-2013) vary widely over time showing no significant trends. Results…

  20. Health and Climate Impacts of Ocean-Going Vessels in East Asia

    NASA Technical Reports Server (NTRS)

    Liu, Huan; Fu, Mingliang; Jin, Xinxin; Shang, Yi; Shindell, Drew; Faluvegi, Greg; Shindell, Cary; He, Kebin

    2016-01-01

    East Asia has the most rapidly growing shipping emissions of both CO2 and traditional air pollutants, but the least in-depth analysis. Full evaluation of all pollutants is needed to assess the impacts of shipping emissions. Here, using an advanced method based on detailed dynamic ship activity data, we show that shipping emissions in East Asia accounted for 16% of global shipping CO2 in 2013, compared to only 4-7% in 2002-2005. Increased emissions lead to large adverse health impacts, with 14,500-37,500 premature deaths per year. Global mean radiative forcing from East Asian shipping is initially negative, but would become positive after approximately eight years for constant current emissions. As a large fraction of vessels are registered elsewhere, joint efforts are necessary to reduce emissions and mitigate the climate and health impacts of shipping in the region.