WorldWideScience

Sample records for retention test results

  1. Influence of PBL with open-book tests on knowledge retention measured with progress tests

    NARCIS (Netherlands)

    Heijne-Penninga, M.; Kuks, J. B. M.; Hofman, W. H. A.; Muijtjens, A. M. M.; Cohen-Schotanus, J.

    The influence of problem-based learning (PBL) and open-book tests on long-term knowledge retention is unclear and subject of discussion. Hypotheses were that PBL as well as open-book tests positively affect long-term knowledge retention. Four progress test results of fifth and sixth-year medical

  2. Results of Large-Scale Testing on Effects of Anti-Foam Agent on Gas Retention and Release

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Charles W.; Guzman-Leong, Consuelo E.; Arm, Stuart T.; Butcher, Mark G.; Golovich, Elizabeth C.; Jagoda, Lynette K.; Park, Walter R.; Slaugh, Ryan W.; Su, Yin-Fong; Wend, Christopher F.; Mahoney, Lenna A.; Alzheimer, James M.; Bailey, Jeffrey A.; Cooley, Scott K.; Hurley, David E.; Johnson, Christian D.; Reid, Larry D.; Smith, Harry D.; Wells, Beric E.; Yokuda, Satoru T.

    2008-01-03

    The U.S. Department of Energy (DOE) Office of River Protection’s Waste Treatment Plant (WTP) will process and treat radioactive waste that is stored in tanks at the Hanford Site. The waste treatment process in the pretreatment facility will mix both Newtonian and non-Newtonian slurries in large process tanks. Process vessels mixing non-Newtonian slurries will use pulse jet mixers (PJMs), air sparging, and recirculation pumps. An anti-foam agent (AFA) will be added to the process streams to prevent surface foaming, but may also increase gas holdup and retention within the slurry. The work described in this report addresses gas retention and release in simulants with AFA through testing and analytical studies. Gas holdup and release tests were conducted in a 1/4-scale replica of the lag storage vessel operated in the Pacific Northwest National Laboratory (PNNL) Applied Process Engineering Laboratory using a kaolin/bentonite clay and AZ-101 HLW chemical simulant with non-Newtonian rheological properties representative of actual waste slurries. Additional tests were performed in a small-scale mixing vessel in the PNNL Physical Sciences Building using liquids and slurries representing major components of typical WTP waste streams. Analytical studies were directed at discovering how the effect of AFA might depend on gas composition and predicting the effect of AFA on gas retention and release in the full-scale plant, including the effects of mass transfer to the sparge air. The work at PNNL was part of a larger program that included tests conducted at Savannah River National Laboratory (SRNL) that is being reported separately. SRNL conducted gas holdup tests in a small-scale mixing vessel using the AZ-101 high-level waste (HLW) chemical simulant to investigate the effects of different AFAs, their components, and of adding noble metals. Full-scale, single-sparger mass transfer tests were also conducted at SRNL in water and AZ-101 HLW simulant to provide data for PNNLâ

  3. 16 CFR 1203.16 - Dynamic strength of retention system test.

    Science.gov (United States)

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Dynamic strength of retention system test.... (2) The retention system strength test equipment shall consist of a dynamic impact apparatus that... stirrup. (2) Mark the pre-test position of the retention system, with the entire dynamic test apparatus...

  4. The effect of testing versus restudy on retention: a meta-analytic review of the testing effect.

    Science.gov (United States)

    Rowland, Christopher A

    2014-11-01

    Engaging in a test over previously studied information can serve as a potent learning event, a phenomenon referred to as the testing effect. Despite a surge of research in the past decade, existing theories have not yet provided a cohesive account of testing phenomena. The present study uses meta-analysis to examine the effects of testing versus restudy on retention. Key results indicate support for the role of effortful processing as a contributor to the testing effect, with initial recall tests yielding larger testing benefits than recognition tests. Limited support was found for existing theoretical accounts attributing the testing effect to enhanced semantic elaboration, indicating that consideration of alternative mechanisms is warranted in explaining testing effects. Future theoretical accounts of the testing effect may benefit from consideration of episodic and contextually derived contributions to retention resulting from memory retrieval. Additionally, the bifurcation model of the testing effect is considered as a viable framework from which to characterize the patterns of results present across the literature. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  5. The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

    Science.gov (United States)

    Chang, Sau Hou

    2017-01-01

    The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate, delayed). Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test) and the repeated test trials (studied the stimulus words once and took three consecutive free-recall tests), and then to the shallow processing level (asked whether each stimulus word was presented in capital letter or in small letter) and the deep processing level (whether each stimulus word belonged to a particular category) to study forty stimulus words. The immediate test was administered five minutes after the trials, whereas the delayed test was administered one week later. Results showed that single test trial recalled more words than repeated test trial in immediate final free-recall test, participants in deep processing performed better than those in shallow processing in both immediate and delayed retention. However, the dominance of single test trial and deep processing did not happen in delayed retention. Additional study trials did not further enhance the delayed retention of words encoded in deep processing, but did enhance the delayed retention of words encoded in shallow processing. PMID:28344679

  6. The Effects of Test Trial and Processing Level on Immediate and Delayed Retention.

    Science.gov (United States)

    Chang, Sau Hou

    2017-03-01

    The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate, delayed). Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test) and the repeated test trials (studied the stimulus words once and took three consecutive free-recall tests), and then to the shallow processing level (asked whether each stimulus word was presented in capital letter or in small letter) and the deep processing level (whether each stimulus word belonged to a particular category) to study forty stimulus words. The immediate test was administered five minutes after the trials, whereas the delayed test was administered one week later. Results showed that single test trial recalled more words than repeated test trial in immediate final free-recall test, participants in deep processing performed better than those in shallow processing in both immediate and delayed retention. However, the dominance of single test trial and deep processing did not happen in delayed retention. Additional study trials did not further enhance the delayed retention of words encoded in deep processing, but did enhance the delayed retention of words encoded in shallow processing.

  7. The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

    Directory of Open Access Journals (Sweden)

    Sau Hou Chang

    2017-03-01

    Full Text Available The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test and processing level (shallow, deep, and one within-subject factor of final recall (immediate, delayed. Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test and the repeated test trials (studied the stimulus words once and took three consecutive free-recall tests, and then to the shallow processing level (asked whether each stimulus word was presented in capital letter or in small letter and the deep processing level (whether each stimulus word belonged to a particular category to study forty stimulus words. The immediate test was administered five minutes after the trials, whereas the delayed test was administered one week later. Results showed that single test trial recalled more words than repeated test trial in immediate final free-recall test, participants in deep processing performed better than those in shallow processing in both immediate and delayed retention. However, the dominance of single test trial and deep processing did not happen in delayed retention. Additional study trials did not further enhance the delayed retention of words encoded in deep processing, but did enhance the delayed retention of words encoded in shallow processing.

  8. Reducing turnaround time for laboratory test results does not improve retention of stable HIV-infected adults on POV program: experience from Uganda.

    Science.gov (United States)

    Maselle, Edna; Muhanguzi, Asaph; Muhumuza, Simon; Nansubuga, Jeniffer; Nawavvu, Cecilia; Namusobya, Jeniffer; Kamya, Moses R; Semitala, Fred C

    2014-01-01

    HIV/ AIDS clinics in resource limited settings (RLS) face increasing numbers of patients and workforce shortage [1, 2]. To address these challenges, efficient models of care like pharmacy only visits (POV) and nurse only visits (NOV) are recommended [3]. The Makerere University Joint AIDS Program (MJAP), a PEPFAR funded program providing care to over 42,000 HIV infected adults has implemented the POV model since 2009. In this model, stable patients on antiretroviral therapy (ART) with adherence to ART >95% and Karnofsky score >90% are reviewed by a doctor every four months but visit pharmacy for ART re-fills every two months. A study conducted in August 2011 showed low retention on the POV program with symptomatic diseases, pending CD4 count, complete blood count results, and poor adherence to ART as the major reasons for the non-retention in the POV program. To improve retention on POV, the TAT (Turnaround Time) for laboratory results (the main reason for non-retention in the previous study) was reduced from one month to one week. In August 2012, the study was repeated to assess the effect of reducing TAT on improving retention one year after patients were placed on POV. A cohort analysis of data from patients in August 2011 and in August 2012 on POV was done. We compared retention of POV before and after reducing the TAT for laboratory results. Retention on POV was 12.0% (95% CI 9.50-14.7) among 619 patients in 2011, (70% Females), mean age was 33 years, Standard Deviation (SD) 8.5 compared to 11.1% (95% CI 9.15-13.4) among 888 patients (70% Females), mean age 38.3 years, SD 8.9 in 2012 (p=0.59). The main reasons for non-retention on the POV program in 2012 were poor adherence to ART (23%) and missed clinic appointments (14%). Reducing TAT for laboratory test results did not improve retention of stable HIV-infected adults on POV in our clinic. Strategies for improving adherence to ART and keeping clinic appointments need to be employed to balance workload and

  9. Retention of Prose Following Testing with Different Types of Tests.

    Science.gov (United States)

    Duchastel, Philippe C.

    1981-01-01

    Taking a test on a passage one has just studied is known to enhance later retention. This effect was influenced by the type of initial test used. It was evident in the case of the initial short-answer test, but not in the case of multiple choice and free recall tests. (Author/RD)

  10. Bubble retention in synthetic sludge: Testing of alternative gas retention apparatus

    International Nuclear Information System (INIS)

    Rassat, S.D.; Gauglitz, P.A.

    1995-07-01

    Several of the underground storage tanks currently used to store waste at Hanford have been placed on the Flammable Gas Watch List, because the waste is either known or suspected to generate, store, and episodically release flammable gases. The objective of this experimental study is to develop a method to measure gas bubble retention in simulated tank waste and in diluted simulant. The method and apparatus should (1) allow for reasonably rapid experiments, (2) minimize sample disturbance, and (3) provide realistic bubble nucleation and growth. The scope of this experimental study is to build an apparatus for measuring gas retention in simulated waste and to design the apparatus to be compatible with future testing on actual waste. The approach employed for creating bubbles in sludge involves dissolving a soluble gas into the supernatant liquid at an elevated pressure, recirculating the liquid containing the dissolved gas through the sludge, then reducing the pressure to allow bubbles to nucleate and grow. Results have been obtained for ammonia as the soluble gas and SY1-SIM-91A, a chemically representative simulated tank waste. In addition, proof-of-principle experiments were conducted with both ammonia and CO 2 as soluble gases and sludge composed of 90-micron glass beads. Results are described

  11. Retention of children under 18 months testing HIV positive in care in ...

    African Journals Online (AJOL)

    Retention of children under 18 months testing HIV positive in care in Swaziland: a retrospective study. ... children within the first two months of life and linking them into care. However, as time progresses the retention of children in care declines. Innovative strategies need to be developed to enhance patient retention.

  12. Radionuclide Retention Mechanisms in Secondary Waste-Form Testing: Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Um, Wooyong; Valenta, Michelle M.; Chung, Chul-Woo; Yang, Jungseok; Engelhard, Mark H.; Serne, R. Jeffrey; Parker, Kent E.; Wang, Guohui; Cantrell, Kirk J.; Westsik, Joseph H.

    2011-09-26

    This report describes the results from laboratory tests performed at Pacific Northwest National Laboratory (PNNL) for Washington River Protection Solutions (WRPS) to evaluate candidate stabilization technologies that have the potential to successfully treat liquid secondary waste stream effluents produced by the Hanford Tank Waste Treatment and Immobilization Plant (WTP). WRPS is considering the design and construction of a Solidification Treatment Unit (STU) for the Effluent Treatment Facility (ETF) at Hanford. The ETF, a multi-waste, treatment-and-storage unit that has been permitted under the Resource Conservation and Recovery Act (RCRA), can accept dangerous, low-level, and mixed wastewaters for treatment. The STU needs to be operational by 2018 to receive secondary liquid waste generated during operation of the WTP. The STU will provide the additional capacity needed for ETF to process the increased volume of secondary waste expected to be produced by WTP. This report on radionuclide retention mechanisms describes the testing and characterization results that improve understanding of radionuclide retention mechanisms, especially for pertechnetate, {sup 99}TcO{sub 4}{sup -} in four different waste forms: Cast Stone, DuraLith alkali aluminosilicate geopolymer, encapsulated fluidized bed steam reforming (FBSR) product, and Ceramicrete phosphate bonded ceramic. These data and results will be used to fill existing data gaps on the candidate technologies to support a decision-making process that will identify a subset of the candidate waste forms that are most promising and should undergo further performance testing.

  13. Testing to Enhance Retention in Human Anatomy

    Science.gov (United States)

    Logan, Jessica M.; Thompson, Andrew J.; Marshak, David W.

    2011-01-01

    Recent work in cognitive psychology has shown that repeatedly testing one's knowledge is a powerful learning aid and provides substantial benefits for retention of the material. To apply this in a human anatomy course for medical students, 39 fill-in-the-blank quizzes of about 50 questions each, one for each region of the body, and four about the


  14. Introduction to Test Facility for Iodine Retention in Filtered Containment Venting System

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jaehoon; An, Sang Mo; Ha, Kwang Soon; Kim, Hwan Yeol [KAERI, Daejeon (Korea, Republic of)

    2015-05-15

    In many countries the implementation of FCVS's is under discussion to mitigate fission product release not only in the short-term but also in the long-term view. To verify the performance of FCVS, the large-scaled tests have been performed such as advanced containment experiments (ACE), the iodine and aerosol retention rate test facility (JAVA), etc. The elemental and organic iodides are the main gaseous iodine species in the containment atmosphere. For the iodine retention, experimental programs have confirmed the existence of gaseous organic iodine in some cases in higher concentrations than for gaseous molecular iodine (I{sub 2}). The Reaction of Methyl iodide (CH{sub 3}I) with surfaces and the removal by containment filters and scrubbers is less efficient in comparison to molecular iodine. In the recent years, an experimental and analytical work has been conducted at the Paul Scherrer Institute (PSI) to develop a process leading to a fast, comprehensive and reliable retention of volatile iodine species in aqueous solutions. New FCVS test facility to verify the performance of FCVS is designed and under construction. The iodine retention tests are planned with elemental iodine or with organic iodide loaded carrier gas consisting of pure non-condensable gas, pure steam and of typical mixtures of non-condensable gas/steam. This paper introduces the iodine generation and measurement system for the iodine retention test of FCVS. In severe accidents elemental and organic iodides are the main gaseous iodine species in the containment atmosphere. Release of the gaseous species in sufficient quantities from containment to environment generates a risk for public health. The filtered containment venting systems (FCVS) can considerably reduce the leakage of radioactive materials to the environment. New integral test facility is prepared to verify a performance of the FCVS. The test facility consists of a test vessel, thermal-hydraulic, and aerosol/iodine generation and

  15. The Effect of Retention Interval Task Difficulty on Young Children's Prospective Memory: Testing the Intention Monitoring Hypothesis

    Science.gov (United States)

    Mahy, Caitlin E. V.; Moses, Louis J.

    2015-01-01

    The current study examined the impact of retention interval task difficulty on 4- and 5-year-olds' prospective memory (PM) to test the hypothesis that children periodically monitor their intentions during the retention interval and that disrupting this monitoring may result in poorer PM performance. In addition, relations among PM, working memory,


  16. 16 CFR Figure 8 to Part 1203 - Apparatus for Test of Retention System Strength

    Science.gov (United States)

    2010-01-01

    ...—Apparatus for Test of Retention System Strength ER10MR98.008 ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Apparatus for Test of Retention System Strength 8 Figure 8 to Part 1203 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT...

  17. Effect of collaborative testing on learning and retention of course content in nursing students.

    Science.gov (United States)

    Rivaz, Mozhgan; Momennasab, Marzieh; Shokrollahi, Paymaneh

    2015-10-01

    Collaborative testing is a learning strategy that provides students with the opportunity to learn and practice collaboration. This study aimed to determine the effect of collaborative testing on test performance and retention of course content in nursing students of Shiraz University of Medical Sciences, Shiraz, Iran. This quasi-experimental study was carried out on 84 students enrolled in the course of Medical-Surgical 2 in Spring 2013 and Fall 2013 semesters. The control group consisting of 39 students participated in the first mid-term exam in an individual format. The intervention group, on the other hand, consisted of 45 students who took the test in a two-stage process. The first stage included an individual testing, while the second stage was a collaborative one given in groups of five individuals chosen randomly. Four weeks later, in order to investigate retention of the course content, both groups took part in the second mid-term exam held individually. The study findings showed significant difference between the mean scores in the intervention group in the Fall 2013 semester (p=0.001). Besides, a statistically significant difference was found between the two groups regarding the tests mean scores (p=0.001). Moreover, retention of course content improved in the collaborative group (p=0.001). The results indicated an increase in test performance and a long-term learning enhancement in collaborative testing compared with the traditional method. Collaborative testing, as an active learning technique and a valuable assessment method, can help nursing instructors provide the alumni with strong problem-solving and critical thinking abilities at healthcare environments.

  18. A more powerful test based on ratio distribution for retention noninferiority hypothesis.

    Science.gov (United States)

    Deng, Ling; Chen, Gang

    2013-03-11

    Rothmann et al. ( 2003 ) proposed a method for the statistical inference of fraction retention noninferiority (NI) hypothesis. A fraction retention hypothesis is defined as a ratio of the new treatment effect verse the control effect in the context of a time to event endpoint. One of the major concerns using this method in the design of an NI trial is that with a limited sample size, the power of the study is usually very low. This makes an NI trial not applicable particularly when using time to event endpoint. To improve power, Wang et al. ( 2006 ) proposed a ratio test based on asymptotic normality theory. Under a strong assumption (equal variance of the NI test statistic under null and alternative hypotheses), the sample size using Wang's test was much smaller than that using Rothmann's test. However, in practice, the assumption of equal variance is generally questionable for an NI trial design. This assumption is removed in the ratio test proposed in this article, which is derived directly from a Cauchy-like ratio distribution. In addition, using this method, the fundamental assumption used in Rothmann's test, that the observed control effect is always positive, that is, the observed hazard ratio for placebo over the control is greater than 1, is no longer necessary. Without assuming equal variance under null and alternative hypotheses, the sample size required for an NI trial can be significantly reduced if using the proposed ratio test for a fraction retention NI hypothesis.

  19. Long-term retention of a divided attention psycho-motor test combining choice reaction test and postural balance test: A preliminary study.

    Science.gov (United States)

    Rossi, R; Pascolo, P B

    2015-09-01

    Driving in degraded psychophysical conditions, such as under the influence of alcohol or drugs but also in a state of fatigue or drowsiness, is a growing problem. The current roadside tests used for detecting drugs from drivers suffer various limitations, while impairment is subjective and does not necessarily correlate with drug metabolite concentration found in body fluids. This work is a validation step towards the study of feasibility of a novel test conceived to assess psychophysical conditions of individuals performing at-risk activities. Motor gestures, long-term retention and learning phase related to the protocol are analysed in unimpaired subjects. The protocol is a divided attention test, which combines a critical tracking test achieved with postural movements and a visual choice reaction test. Ten healthy subjects participated in a first set of trials and in a second set after about six months. Each session required the carrying out of the test for ten times in order to investigate learning effect and performance over repetitions. In the first set the subjects showed a learning trend up to the third trial, whilst in the second set of trials they showed motor retention. Nevertheless, the overall performance did not significantly improve. Gestures are probably retained due to the type of tasks and the way in which the instructions are conveyed to the subjects. Moreover, motor retention after a short training suggests that the protocol is easy to learn and understand. Implications for roadside test usage and comparison with current tests are also discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Charge retention test experiences on Hubble Space Telescope nickel-hydrogen battery cells

    Science.gov (United States)

    Nawrocki, Dave E.; Driscoll, J. R.; Armantrout, J. D.; Baker, R. C.; Wajsgras, H.

    1993-01-01

    The Hubble Space Telescope (HST) nickel-hydrogen battery module was designed by Lockheed Missile & Space Co (LMSC) and manufactured by Eagle-Picher Ind. (EPI) for the Marshall Space Flight Center (MSFC) as an Orbital Replacement Unit (ORU) for the nickel-cadmium batteries originally selected for this low earth orbit mission. The design features of the HST nickel hydrogen battery are described and the results of an extended charge retention test are summarized.

  1. Effects of audio-visual aids on foreign language test anxiety, reading and listening comprehension, and retention in EFL learners.

    Science.gov (United States)

    Lee, Shu-Ping; Lee, Shin-Da; Liao, Yuan-Lin; Wang, An-Chi

    2015-04-01

    This study examined the effects of audio-visual aids on anxiety, comprehension test scores, and retention in reading and listening to short stories in English as a Foreign Language (EFL) classrooms. Reading and listening tests, general and test anxiety, and retention were measured in English-major college students in an experimental group with audio-visual aids (n=83) and a control group without audio-visual aids (n=94) with similar general English proficiency. Lower reading test anxiety, unchanged reading comprehension scores, and better reading short-term and long-term retention after four weeks were evident in the audiovisual group relative to the control group. In addition, lower listening test anxiety, higher listening comprehension scores, and unchanged short-term and long-term retention were found in the audiovisual group relative to the control group after the intervention. Audio-visual aids may help to reduce EFL learners' listening test anxiety and enhance their listening comprehension scores without facilitating retention of such materials. Although audio-visual aids did not increase reading comprehension scores, they helped reduce EFL learners' reading test anxiety and facilitated retention of reading materials.

  2. Thermal effect on water retention curve of bentonite: experiment and thermodynamic modeling

    International Nuclear Information System (INIS)

    Qin Bing; Chen Zhenghai; Sun Faxin; Liu Yuemiao; Wang Ju

    2012-01-01

    The thermal effects on water retention curve of GMZ bentonite were investigated experimentally and theoretically. Water retention tests were conducted on GMZ bentonite at five temperatures ranging from 20℃ to 100℃. Test results showed that the water retention capacity and the hysteresis of the water retention curve decreased with increasing temperature, and that the water retention curves at different temperatures were almost parallel to each other. Based on the thermodynamics of sorption, a model was established to describe the temperature influence on the water retention curve. The model was validated by comparing the model predictions and the test results. (authors)

  3. Collaborative-group testing improves learning and knowledge retention of human physiology topics in second-year medical students.

    Science.gov (United States)

    VĂĄzquez-GarcĂ­a, Mario

    2018-06-01

    The present study examined the relationship between second-year medical students' group performance and individual performance in a collaborative-learning environment. In recent decades, university professors in the scientific and humanistic disciplines have successfully put into practice different modalities of collaborative approaches to teaching. Essentially, collaborative approach refers to a variety of techniques that involves the joint intellectual effort of a small group of students, which encourages interaction and discussion among students and professors. The present results show the efficacy of collaborative learning, which, furthermore, allowed students to participate actively in the physiology class. Average student's grades were significantly higher when they engaged in single-best-response, multiple-choice tests as a student team, compared with taking the same examinations individually. The method improved notably knowledge retention, as learning is more effective when performed in the context of collaborative partnership. A selected subset of questions answered wrongly in an initial test, both individually and collectively, was used on a second test to examine student retention of studied material. Grade averages were significantly improved, both individually and groupwise, when students responded to the subset of questions a second time, 1, 2, or 3 wk after the first attempt. These results suggest that the collaborative approach to teaching allowed a more effective understanding of course content, which meant an improved capacity for retention of human physiology knowledge.

  4. The effects of generative testing on text retention and text comprehension

    NARCIS (Netherlands)

    Dirkx, Kim; Kester, Liesbeth; Kirschner, Paul A.

    2011-01-01

    Dirkx, K. J. H., Kester, L., & Kirschner, P. A. (2011, 30 August). The effects of generative testing methods on text retention and text comprehension. Paper presented at the annual meeting of the European Association for Research on Learning and Instruction, Exeter, United Kingdom.

  5. Effect of soy protein isolate in the diet on retention by the rat of iron from radiolabeled test meals

    International Nuclear Information System (INIS)

    Thompson, D.B.; Erdman, J.W. Jr.

    1984-01-01

    The influence of soy protein isolate (SPI) in the diet on whole-body retention of extrinsically radiolabeled iron from test meals containing or not containing SPI was evaluated in marginally iron-deficient weanling rats. In experiment 1 SPI was compared with casein in a 2 X 2 factorial design: diets and test meals were either SPI-based or casein-based. Diets were fed for 13 days prior to the test meal and for 7 days subsequent to the test meal. Rats fed the SPI-based diet retained less iron from test meals than did rats fed the casein-based diet (66.1 vs. 74.8%, P less than 0.01). Experiment 2 showed that an SPI-based diet fed during the final 4 days of a 14-day pre-test meal period and subsequent to the test meal led to less iron retention compared to a casein-based diet. In addition to the observed diet effect, experiment 1 showed that iron retention was less from an SPI-based test meal than from a casein-based test meal, confirming previous reports of adverse effects of SPI on iron retention. The present experiments show that SPI can adversely affect from retention in two ways: by its presence in the diet before and after a test meal, and by its presence in a test meal

  6. The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

    Science.gov (United States)

    Chang, Sau Hou

    2017-01-01

    The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate,


  7. Lesser Neural Pattern Similarity across Repeated Tests Is Associated with Better Long-Term Memory Retention.

    Science.gov (United States)

    Karlsson Wirebring, Linnea; Wiklund-Hörnqvist, Carola; Eriksson, Johan; Andersson, Micael; Jonsson, Bert; Nyberg, Lars

    2015-07-01

    Encoding and retrieval processes enhance long-term memory performance. The efficiency of encoding processes has recently been linked to representational consistency: the reactivation of a representation that gets more specific each time an item is further studied. Here we examined the complementary hypothesis of whether the efficiency of retrieval processes also is linked to representational consistency. Alternatively, recurrent retrieval might foster representational variability--the altering or adding of underlying memory representations. Human participants studied 60 Swahili-Swedish word pairs before being scanned with fMRI the same day and 1 week later. On Day 1, participants were tested three times on each word pair, and on Day 7 each pair was tested once. A BOLD signal change in right superior parietal cortex was associated with subsequent memory on Day 1 and with successful long-term retention on Day 7. A representational similarity analysis in this parietal region revealed that beneficial recurrent retrieval was associated with representational variability, such that the pattern similarity on Day 1 was lower for retrieved words subsequently remembered compared with those subsequently forgotten. This was mirrored by a monotonically decreased BOLD signal change in dorsolateral prefrontal cortex on Day 1 as a function of repeated successful retrieval for words subsequently remembered, but not for words subsequently forgotten. This reduction in prefrontal response could reflect reduced demands on cognitive control. Collectively, the results offer novel insights into why memory retention benefits from repeated retrieval, and they suggest fundamental differences between repeated study and repeated testing. Repeated testing is known to produce superior long-term retention of the to-be-learned material compared with repeated encoding and other learning techniques, much because it fosters repeated memory retrieval. This study demonstrates that repeated memory

  8. Pennsylvania Academic Libraries and Student Retention and Graduation: A Preliminary Investigation with Confusing Results

    Directory of Open Access Journals (Sweden)

    Gregory A. Crawford

    2014-11-01

    Full Text Available This study examined the relationships between specific institutional financial variables and two library-related variables on graduation and retention rates for colleges and universities through correlations and multiple regression analysis. The analyses used data for Pennsylvania colleges and universities that were extracted from the Integrated Postsecondary Educational Data System (IPEDS and the Academic Libraries Survey (ALS.  All analyses were run using IBM SPSS software. The correlations showed that both library expenses per student and library use per student were significantly correlated with both graduation and retention rates. In contrast, the multiple regression results showed that neither library budgets nor library use had significant effects on either graduation rates or retention rates. As would be expected, instructional expenses per student had the highest correlation with both graduation and retention and also yielded the strongest coefficient in the resulting regression equations.

  9. Retention in HIV Care between Testing and Treatment in Sub-Saharan Africa: A Systematic Review

    Science.gov (United States)

    Rosen, Sydney; Fox, Matthew P.

    2011-01-01

    Background Improving the outcomes of HIV/AIDS treatment programs in resource-limited settings requires successful linkage of patients testing positive for HIV to pre–antiretroviral therapy (ART) care and retention in pre-ART care until ART initiation. We conducted a systematic review of pre-ART retention in care in Africa. Methods and Findings We searched PubMed, ISI Web of Knowledge, conference abstracts, and reference lists for reports on the proportion of adult patients retained between any two points between testing positive for HIV and initiating ART in sub-Saharan African HIV/AIDS care programs. Results were categorized as Stage 1 (from HIV testing to receipt of CD4 count results or clinical staging), Stage 2 (from staging to ART eligibility), or Stage 3 (from ART eligibility to ART initiation). Medians (ranges) were reported for the proportions of patients retained in each stage. We identified 28 eligible studies. The median proportion retained in Stage 1 was 59% (35%–88%); Stage 2, 46% (31%–95%); and Stage 3, 68% (14%–84%). Most studies reported on only one stage; none followed a cohort of patients through all three stages. Enrollment criteria, terminology, end points, follow-up, and outcomes varied widely and were often poorly defined, making aggregation of results difficult. Synthesis of findings from multiple studies suggests that fewer than one-third of patients testing positive for HIV and not yet eligible for ART when diagnosed are retained continuously in care, though this estimate should be regarded with caution because of review limitations. Conclusions Studies of retention in pre-ART care report substantial loss of patients at every step, starting with patients who do not return for their initial CD4 count results and ending with those who do not initiate ART despite eligibility. Better health information systems that allow patients to be tracked between service delivery points are needed to properly evaluate pre-ART loss to care, and

  10. Pilot Testing for Feasibility in a Study of Student Retention and Attrition in Online Undergraduate Programs

    Science.gov (United States)

    Fraser, Joy; Fahlman, Dorothy; Arscott, Jane; Guillot, Isabelle

    2018-01-01

    Prior to undertaking a descriptive study on attrition and retention of students in two online undergraduate health administration and human service programs, a pilot test was conducted to assess the procedures for participant recruitment, usability of the survey questionnaire, and data collection processes. A retention model provided the


  11. The Effects of Test Trial and Processing Level on Immediate and Delayed Retention

    OpenAIRE

    Chang, Sau Hou

    2017-01-01

    The purpose of the present study was to investigate the effects of test trial and processing level on immediate and delayed retention. A 2 × 2 × 2 mixed ANOVAs was used with two between-subject factors of test trial (single test, repeated test) and processing level (shallow, deep), and one within-subject factor of final recall (immediate, delayed). Seventy-six college students were randomly assigned first to the single test (studied the stimulus words three times and took one free-recall test...

  12. Semantic Information Activated during Retrieval Contributes to Later Retention: Support for the Mediator Effectiveness Hypothesis of the Testing Effect

    Science.gov (United States)

    Carpenter, Shana K.

    2011-01-01

    Previous research has proposed that tests enhance retention more than do restudy opportunities because they promote the effectiveness of mediating information--that is, a word or concept that links a cue to a target (Pyc & Rawson, 2010). Although testing has been shown to promote retention of mediating information that participants were asked


  13. Retention Load of Telescopic Crowns with Different Taper Angles between Cobalt-Chromium and Polyetheretherketone Made with Three Different Manufacturing Processes Examined by Pull-Off Test.

    Science.gov (United States)

    Wagner, Christina; Stock, Veronika; Merk, Susanne; Schmidlin, Patrick R; Roos, Malgorzata; Eichberger, Marlis; Stawarczyk, Bogna

    2018-02-01

    To investigate the retention loads of differently fabricated secondary telescopic polyetheretherketone (PEEK) crowns on cobalt-chromium primary crowns with different tapers. Cobalt-chromium primary crowns with 0°, 1°, and 2° tapers were constructed, milled, and sintered. Corresponding secondary crowns were fabricated by milling, pressing from pellets, and pressing from granules. For these nine test groups, the pull-off tests of each crown combination were performed 20 times, and the retention loads were measured (Zwick 1445, 50 mm/min). Data were analyzed using linear regression, covariance analysis, mixed models, Kruskal-Wallis, and Mann-Whitney U-test, together with the Benferroni-Holm correction. The mixed models covariance analysis reinforced stable retention load values (p = 0.162) for each single test sequence. There was no interaction between the groups and the separation cycles (p = 0.179). Milled secondary crowns with 0° showed the lowest mean retention load values compared to all tested groups (p = 0.003) followed by those pressed form pellets with 1°. Regarding the different tapers, no effect of manufacturing method on the results was observed within 1° and 2° groups (p = 0.540; p = 0.052); however, among the 0° groups, the milled ones showed significantly the lowest retention load values (p = 0.002). Among the manufacturing methods, both pressed groups showed no impact of taper on the retention load values (p > 0.324 and p > 0.123, respectively), whereas among the milled secondary crowns, the 0° taper showed significantly lower retention load values than the 1° and 2° taper (p test sequence; however, data with thermo-mechanical aging are still required. In addition, further developments in CAD/CAM manufacturing of PEEK materials for telescopic crowns are warranted, especially for 0°. © 2016 by the American College of Prosthodontists.

  14. Iodine, krypton and xenon retention efficiencies of silver impregnated silica gel media with different silver loadings and under different test conditions

    International Nuclear Information System (INIS)

    Motes, B.G.; Fernandez, S.J.; Tkachyk, J.W.

    1983-02-01

    The purpose of an independent study conducted by Exxon Nuclear Idaho, Co. (ENICO) was to evaluate a silver impregnated silica gel adsorption medium associated with a radioiodine air sampler developed at Brookhaven National Laboratory (BNL). Specifically, ENICO's responsibility was to evaluate the iodine and noble gas retention efficiencies of the adsorption medium. The evaluation was comprised of a four-phase program: 1) test assemblies capable of challenging the silver silica gel filled adsorber canister with radioiodine species or noble gases at flow rates up to 10 scfm and relative humidities up to 83% were constructed; 2) more than 45 kgs of the 4 and 8% silver impregnated silica gel were prepared and characterized for particle size distribution, bulk silver content, bulk density, and silver content by particle size; 3) iodine species retention efficiencies of the silver silica gel were determined; and 4 krypton and xenon retention efficiencies were measured. The iodine species retention efficiencies were greater than 90% under most conditions. A combination of flow rates >5 scfm and 4% silver loaded silica gel reduced the methyl iodide retention efficiency to less than 90%. The retention efficiencies for both krypton and xenon were on the order of 8 x 10 -2 % and were not affected greatly by any test variable except test duration. A reduced retention efficiency with increased test durations indicates adsorption equilibrium may be established within five minutes. (author)

  15. Laboratory Tests of Substrate Physical Properties May Not Represent the Retention Capacity of Green Roof Substrates In Situ

    Directory of Open Access Journals (Sweden)

    Christopher Szota

    2017-11-01

    Full Text Available Green roofs can be used to reduce the volume of polluted stormwater that is generated by cities. Modelling rainfall retention is critical, but green roof water balance models often rely on the physical properties of substrates. In these models, substrate water holding capacity (WHC determines the depth of water which can be stored before runoff is generated; whereas, the permanent wilting point (PWP limits evapotranspiration. The WHC and PWP, as well as plant available water (PAW; where PAW = WHC − PWP, as determined from laboratory tests, may not truly reflect how substrates perform on green roofs. We therefore ran a simulated rainfall experiment on green roof modules to (i compare the rainfall retention of vegetated and non-vegetated substrates with different WHC and PAW, and (ii relate retention to substrate storage capacity, as calculated from laboratory measures of WHC and PAW. We found that the PAW of a substrate is a better indicator of evapotranspiration and retention when compared with WHC. However, we also found that substrates always retained less water than their calculated storage capacity would suggest, most likely being due to their high permeability. Our results indicate that using laboratory-derived measures of WHC and PAW in green roof models may be over-estimating both evapotranspiration and rainfall retention.

  16. Retention of Emergency Care Knowledge.

    Science.gov (United States)

    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)

  17. When Does Testing Enhance Retention? A Distribution-Based Interpretation of Retrieval as a Memory Modifier

    Science.gov (United States)

    Halamish, Vered; Bjork, Robert A.

    2011-01-01

    Tests, as learning events, can enhance subsequent recall more than do additional study opportunities, even without feedback. Such advantages of testing tend to appear, however, only at long retention intervals and/or when criterion tests stress recall, rather than recognition, processes. We propose that the interaction of the benefits of testing


  18. Retention of Knowledge following training of students in Basic Trauma Life Support.

    Science.gov (United States)

    Lim, K G; Lum, S K; Burud, I A S

    2016-12-01

    In the course of their undergraduate training at the International Medical University, students receive a Basic Trauma Life Support course. We wanted to test the long-term retention of knowledge (after 16 months) of third year medical students who had received training in Basic Trauma Life Support Method: To assess the retention of knowledge one cohort of students who received the training course were tested again 16 months later using the same 30 question One Best Answer quiz. Seventy-three students who underwent the course sat for the Retention test. The number of students who passed the Retention test was not significantly different from the test taken immediately after the course. The mean scores, 62.5% and 59.5% respectively, were however significantly different. Our study involves a relatively long interval between the course and retention of knowledge test shows encouraging results.

  19. Iodine, krypton and xenon retention efficiencies of silver impregnated silica gel media with different silver loadings and under different test conditions

    Energy Technology Data Exchange (ETDEWEB)

    Motes, B G; Fernandez, S J; Tkachyk, J W

    1983-02-01

    The purpose of an independent study conducted by Exxon Nuclear Idaho, Co. (ENICO) was to evaluate a silver impregnated silica gel adsorption medium associated with a radioiodine air sampler developed at Brookhaven National Laboratory (BNL). Specifically, ENICO's responsibility was to evaluate the iodine and noble gas retention efficiencies of the adsorption medium. The evaluation was comprised of a four-phase program: 1) test assemblies capable of challenging the silver silica gel filled adsorber canister with radioiodine species or noble gases at flow rates up to 10 scfm and relative humidities up to 83% were constructed; 2) more than 45 kgs of the 4 and 8% silver impregnated silica gel were prepared and characterized for particle size distribution, bulk silver content, bulk density, and silver content by particle size; 3) iodine species retention efficiencies of the silver silica gel were determined; and 4 krypton and xenon retention efficiencies were measured. The iodine species retention efficiencies were greater than 90% under most conditions. A combination of flow rates >5 scfm and 4% silver loaded silica gel reduced the methyl iodide retention efficiency to less than 90%. The retention efficiencies for both krypton and xenon were on the order of 8 x 10{sup -2}% and were not affected greatly by any test variable except test duration. A reduced retention efficiency with increased test durations indicates adsorption equilibrium may be established within five minutes. (author)

  20. Tensile test and interface retention forces between wires and composites in lingual fixed retainers.

    Science.gov (United States)

    Paolone, Maria Giacinta; Kaitsas, Roberto; Obach, Patricia; Kaitsas, Vasilios; Benedicenti, Stefano; Sorrenti, Eugenio; Barberi, Fabrizio

    2015-06-01

    In daily orthodontic clinical practice retention is very important, and lingual retainers are part of this challenge. The failure of lingual retainers may be due to many factors. The aim of this study was to assess the retention forces and mechanical behavior of different types of wires matched with different kinds of composites in lingual retainers. A tensile test was performed on cylindrical composite test specimens bonded to orthodontic wires. The specimens were constructed using four different wires: a straight wire (Remanium .016×.022″ Dentaurum), two round twisted wires (Penta One .0215″ Masel, Gold Penta Twisted .0215″ Gold N'braces) and a rectangular braided wire (D-Rect .016×.022″ Ormco); and three composites: two micro-hybrids (Micro-Hybrid Enamel Plus HFO Micerium, and Micro-Hybrid SDR U Dentsply) and a micro-nano-filled composite (Micro-Nano-Filled Transbond LR 3M). The test was performed at a speed of 10mm/min on an Inström device. The wire was fixed with a clamp. The results showed that the bonding between wires and composites in lingual fixed retainers seemed to be lowest for rectangular smooth wires and increased in round twisted and rectangular twisted wires where the bonding was so strong that the maximum tension/bond strength was greater than the ultimate tensile strength of the wire. The highest values were in rectangular twisted wires. Concerning the composites, hybrid composites had the lowest interface bonding values and broke very quickly, while the nano- and micro-composites tolerated stronger forces and displayed higher bonding values. The best results were observed with the golden twisted wire and reached 21.46 MPa with the Transbond composite. With the rectangular braided wire the retention forces were so high that the Enamel Plus composite fractured when the load exceeded 154.6 N/MPa. When the same wire was combined with the Transbond LR either the wire or the composite broke when the force exceeded 240 N. The results of this

  1. Testing plan for critical heat flux measurement during in-vessel retention

    International Nuclear Information System (INIS)

    Aoki, Kazuyoshi; Iwaki, Chikako; Sato, Hisaki; Mimura, Satoshi; Kanamori, Daisuke

    2015-01-01

    In-Vessel Retention (IVR) is a method to maintain molten debris in a reactor vessel (RV) by RV outer surface cooling. Structural integrity of RV and cooling capacity on RV outer surface are important to verify IVR strategy. Critical Heat Flux (CHF) data is necessary to estimate cooling capacity on the RV outer surface. And there are some CHF data to estimate cooling capacity on the RV outer surface. However, these data were obtained for specific plants. Thus, the objective of this study is developing a CHF correlation for various PWR plants. The objectives of this paper are developing test equipment and testing plan for the CHF correlation. Firstly, plant conditions during severe accidents were organized. Then, ranges of testing parameters were estimated with the plant conditions. And specifications of the test equipment were set to cover the range of parameters. Secondly, testing cases were set based on design of experiments. The test cases are suitable to develop experimental correlations. (author)

  2. Soft wheat and flour products methods review: solvent retention capacity equation correction

    Science.gov (United States)

    This article discusses the results of a significant change to calculations made within AACCI Approved methods 56-10 and 56-11, the Alkaline Water Retention Capacity (AWRC) test and the Solvent Retention Capacity (SRC) test. The AACCI Soft Wheat and Flour Products Technical Committee reviewed propos...

  3. Decomposing the interaction between retention interval and study/test practice: the role of retrievability.

    Science.gov (United States)

    Jang, Yoonhee; Wixted, John T; Pecher, Diane; Zeelenberg, René; Huber, David E

    2012-01-01

    Even without feedback, test practice enhances delayed performance compared to study practice, but the size of the effect is variable across studies. We investigated the benefit of testing, separating initially retrievable items from initially nonretrievable items. In two experiments, an initial test determined item retrievability. Retrievable or nonretrievable items were subsequently presented for repeated study or test practice. Collapsing across items, in Experiment 1, we obtained the typical cross-over interaction between retention interval and practice type. For retrievable items, however, the cross-over interaction was quantitatively different, with a small study benefit for an immediate test and a larger testing benefit after a delay. For nonretrievable items, there was a large study benefit for an immediate test, but one week later there was no difference between the study and test practice conditions. In Experiment 2, initially nonretrievable items were given additional study followed by either an immediate test or even more additional study, and one week later performance did not differ between the two conditions. These results indicate that the effect size of study/test practice is due to the relative contribution of retrievable and nonretrievable items.

  4. Refractance Windowℱ drying of haskap berry--preliminary results on anthocyanin retention and physicochemical properties.

    Science.gov (United States)

    Celli, Giovana Bonat; Khattab, Rabie; Ghanem, Amyl; Brooks, Marianne Su-Ling

    2016-03-01

    The goal of this work was to determine the anthocyanin retention and physicochemical properties of haskap powder prepared by Refractance Windowℱ (RW) drying. In general, the RW-dried powder particles had a smooth surface with similar thickness, consistent with the preparation method, and had a solubility of 75.63% in water. The RW-dried powder (consisting of 98% haskap berries) retained approximately 93.8% of anthocyanins from the original frozen fruits, as assessed by the pH-differential method. This result is in good agreement with HPLC analysis that indicated 92.9% retention. Three anthocyanins were identified in frozen berries and RW-dried powder: cyanidin 3-glucoside, cyanidin 3-rutinoside, and peonidin 3-glucoside. Surprisingly, cyanidin 3-rutinoside exhibited the lowest retention. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Associative learning versus fear habituation as predictors of long-term extinction retention.

    Science.gov (United States)

    Brown, Lily A; LeBeau, Richard T; Chat, Ka Yi; Craske, Michelle G

    2017-06-01

    Violation of unconditioned stimulus (US) expectancy during extinction training may enhance associative learning and result in improved long-term extinction retention compared to within-session habituation. This experiment examines variation in US expectancy (i.e., expectancy violation) as a predictor of long-term extinction retention. It also examines within-session habituation of fear-potentiated startle (electromyography, EMG) and fear of conditioned stimuli (CS) throughout extinction training as predictors of extinction retention. Participants (n = 63) underwent fear conditioning, extinction and retention and provided continuous ratings of US expectancy and EMG, as well as CS fear ratings before and after each phase. Variation in US expectancy throughout extinction and habituation of EMG and fear was entered into a regression as predictors of retention and reinstatement of levels of expectancy and fear. Greater variation in US expectancy throughout extinction training was significantly predictive of enhanced extinction performance measured at retention test, although not after reinstatement test. Slope of EMG and CS fear during extinction did not predict retention of extinction. Within-session habituation of EMG and self-reported fear is not sufficient for long-term retention of extinction learning, and models emphasizing expectation violation may result in enhanced outcomes.

  6. Novel word retention in sequential bilingual children.

    Science.gov (United States)

    Kan, Pui Fong

    2014-03-01

    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 either a 2-month or a 4-month delay. Results showed that children retained more words in L1 than in L2 for both of the retention interval conditions. In addition, children's word retention was associated with their existing language knowledge and their fast-mapping performance within and across language. The patterns of association, however, were different between L1 and L2. These findings suggest that children's word retention might be related to the interactions of various components that are operating within a dynamic system.

  7. Lance water injection tests adjacent to the 281-3H retention basin at the Savannah River Site, Aiken, South Carolina

    International Nuclear Information System (INIS)

    Freifeld, B.; Myer, L.; Moridis, G.; Cook, P.; James, A.; Pellerin, L.; Pruess, K.

    1996-09-01

    A pilot-scale field demonstration of waste isolation using viscous- liquid containment barriers has been planned for the 281-3H retention basin at the Savannah River Site, Aiken, SC. The 281-3H basin is a shallow retention/seepage basin contaminated mainly by radionuclides. The viscous-liquid containment barrier utilizes the permeation of liquid grout to either entomb the contaminants within a monolithic grout structure or to isolate the waste by drastically reducing the permeability, of the soils around the plume. A clear understanding of the hydrogeologic setting of the retention basin is necessary for proper design of the viscous liquid barrier. To aid in the understanding of the hydrogeology of the 281-3H retention basin, and to obtain critical parameters necessary for grout injection design, a series of tests were undertaken in a region immediately adjacent to the basin. The objectives of the LWIT were: 1. To evaluate the general performance of the Lance Injection Technique for grout emplacement at the site, including the range and upper limits of injection pressures, the flow rates applicable for site conditions, as well as the mechanical forces needed for lance penetration. 2. To obtain detailed information on the injectability of the soils immediately adjacent to the H-area retention basin. 3. To identify any high permeability zones suitable for injection and evaluate their spatial distribution. 4. To perform ground penetrating radar (GPR) to gain information on the structure of the soil column and to compare the results with LWIT data. This report will focus on results pertinent to these objectives

  8. LWR aerosol containment experiments (LACE) program and initial test results

    International Nuclear Information System (INIS)

    Muhlestein, L.D.; Hilliard, R.K.; Bloom, G.R.; McCormack, J.D.; Rahn, F.J.

    1985-01-01

    The LWR aerosol containment experiments (LACE) program is described. The LACE program is being performed at the Hanford Engineer Development Laboratory (operated by Westinghouse Hanford Company) and the initial tests are sponsored by EPRI. The objectives of the LACE program are: to demonstrate, at large-scale, inherent radioactive aerosol retention behavior for postulated high consequence LWR accident situations; and to provide a data base to be used for aerosol behavior . Test results from the first phase of the LACE program are presented and discussed. Three large-scale scoping tests, simulating a containment bypass accident sequence, demonstrated the extent of agglomeration and deposition of aerosols occurring in the pipe pathway and vented auxiliary building under realistic accident conditions. Parameters varied during the scoping tests were aerosol type and steam condensation

  9. Retention of movement technique : Implications for primary prevention of ACL injuries

    NARCIS (Netherlands)

    Welling, Wouter; Benjaminse, Anne; Gokeler, Alli; Otten, Bert

    2017-01-01

    Background: Retention of movement technique is crucial in anterior cruciate ligament (ACL) injury prevention programs. It is unknown if specific instructions or video instructions result in changes in kinematic and kinetic measures during a relatively short training session, and in a retention test

  10. Study on soil-water retention curves for loess aerated zone

    International Nuclear Information System (INIS)

    Guo Zede; Cheng Jinru; Deng An; Masayuki Mukai; Hideo Kamiyama

    2000-01-01

    The author introduces the measuring method and results of soil-water retention curves of 46 samples taken from ground surface to water table of 28 m depth at CIRP's Field Test Site. The results indicate that the soil-water retention characteristics vary significantly with depth, and the loess-aerated zone at the site can be divided into five layers. From the results, unsaturated hydraulic parameters are deduced, such as conductivity, specific water capacity and equivalent pore diameter. The water velocity calculated from these parameters is satisfactorily consistent with that one obtained from 3 H tracing test carried out at the site

  11. Nosewitness Identification: Effects of Lineup Size and Retention Interval.

    Science.gov (United States)

    Alho, Laura; Soares, Sandra C; Costa, Liliana P; Pinto, Elisa; Ferreira, Jacqueline H T; Sorjonen, Kimmo; Silva, Carlos F; Olsson, Mats J

    2016-01-01

    Although canine identification of body odor (BO) has been widely used as forensic evidence, the concept of nosewitness identification by human observers was only recently put to the test. The results indicated that BOs associated with male characters in authentic crime videos could later be identified in BO lineup tests well above chance. To further evaluate nosewitness memory, we assessed the effects of lineup size (Experiment 1) and retention interval (Experiment 2), using a forced-choice memory test. The results showed that nosewitness identification works for all lineup sizes (3, 5, and 8 BOs), but that larger lineups compromise identification performance in similarity to observations from eye- and earwitness studies. Also in line with previous eye- and earwitness studies, but in disagreement with some studies on odor memory, Experiment 2 showed significant forgetting between shorter retention intervals (15 min) and longer retention intervals (1-week) using lineups of five BOs. Altogether this study shows that identification of BO in a forensic setting is possible and has limits and characteristics in line with witness identification through other sensory modalities.

  12. The contributions of encoding, retention, and recall to the Hebb effect.

    Science.gov (United States)

    Oberauer, Klaus; Meyer, Nadine

    2009-10-01

    The article reports an experiment testing whether the Hebb repetition effect-the gradual improvement of immediate serial recall when the same list is repeated several times-depends on overt recall of the repeated lists. Previous reports which suggest that recall is critical confound the recall manipulation with retention interval. The present experiment orthogonally varies retention interval (0 or 9 s) and whether the list is to be recalled after the retention interval. Hebb repetition learning is assessed in a final test phase. A repetition effect was obtained in all four experimental conditions; it was larger for recalled than non-recalled lists, whereas retention interval had no effect. The results show that encoding is sufficient to generate cumulative long-term learning, which is strengthened by recall. Rehearsal, if it takes place in the retention interval at all, does not have the same effect on long-term learning as overt recall.

  13. Testing and evaluation of existing techniques for identifying uptakes and measuring retention of uranium in mill workers

    International Nuclear Information System (INIS)

    1983-03-01

    Preliminary tests and evaluations of existing bio-analytical techniques for identifying uptakes and measuring retention of uranium in mill workers were made at two uranium mills. Urinalysis tests were found to be more reliable indicators of uranium uptakes than personal air sampling. Static air samples were not found to be good indicators of personal uptakes. In vivo measurements of uranium in lung were successfully carried out in the presence of high and fluctuating background radiation. Interference from external contamination was common during end of shift measurements. A full scale study to evaluate model parameters for the uptake, retention and elimination of uranium should include, in addition to the above techniques, particle size determination of airborne uranium, solubility in simulated lung fluid, uranium analysis in faeces and bone and minute volume measurements for each subject

  14. Selected Test Results from the Encell Technology Nickel Iron Battery

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Summer Kamal Rhodes [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Power Sources R& D; Baca, Wes Edmund [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Power Sources R& D; Avedikian, Kristan [Encell Technology, Alachua, FL (United States)

    2014-09-01

    The performance of the Encell Nickel Iron (NiFe) battery was measured. Tests included capacity, capacity as a function of rate, capacity as a function of temperature, charge retention (28-day), efficiency, accelerated life projection, and water refill evaluation. The goal of this work was to evaluate the general performance of the Encell NiFe battery technology for stationary applications and demonstrate the chemistry's capabilities in extreme conditions. Test results have indicated that the Encell NiFe battery technology can provide power levels up to the 6C discharge rate, ampere-hour efficiency above 70%. In summary, the Encell batteries have met performance metrics established by the manufacturer. Long-term cycle tests are not included in this report. A cycle test at elevated temperature was run, funded by the manufacturer, which Encell uses to predict long-term cycling performance, and which passed their prescribed metrics.

  15. Mechanisms of gas retention and release: Experimental results for Hanford waste tanks 241-AW-101 and 241-AN-103

    Energy Technology Data Exchange (ETDEWEB)

    Rassat, S.D.; Gauglitz, P.A.; Bredt, P.R.; Mahoney, L.A.; Forbes, S.V.; Tingey, S.M.

    1997-09-01

    The 177 storage tanks at Hanford contain a vast array of radioactive waste forms resulting, primarily, from nuclear materials processing. Through radiolytic, thermal, and other decomposition reactions of waste components, gaseous species including hydrogen, ammonia, and the oxidizer nitrous oxide are generated within the waste tanks. Many of these tanks are known to retain and periodically release quantities of these flammable gas mixtures. The primary focus of the Flammable Gas Project is the safe storage of Hanford tank wastes. To this end, we strive to develop an understanding of the mechanisms of flammable gas retention and release in Hanford tanks through laboratory investigations on actual tank wastes. These results support the closure of the Flammable Gas Unreviewed Safety Question (USQ) on the safe storage of waste tanks known to retain flammable gases and support resolution of the broader Flammable Gas Safety Issue. The overall purpose of this ongoing study is to develop a comprehensive and thorough understanding of the mechanisms of flammable gas retention and release. The first objective of the current study was to classify bubble retention and release mechanisms in two previously untested waste materials from Tanks 241-AN-103 (AN-103) and 241-AW-101 (AW-101). Results were obtained for retention mechanisms, release characteristics, and the maximum gas retention. In addition, unique behavior was also documented and compared with previously studied waste samples. The second objective was to lengthen the duration of the experiments to evaluate the role of slowing bubble growth on the retention and release behavior. Results were obtained for experiments lasting from a few hours to a few days.

  16. Mechanisms of gas retention and release: Experimental results for Hanford waste tanks 241-AW-101 and 241-AN-103

    International Nuclear Information System (INIS)

    Rassat, S.D.; Gauglitz, P.A.; Bredt, P.R.; Mahoney, L.A.; Forbes, S.V.; Tingey, S.M.

    1997-09-01

    The 177 storage tanks at Hanford contain a vast array of radioactive waste forms resulting, primarily, from nuclear materials processing. Through radiolytic, thermal, and other decomposition reactions of waste components, gaseous species including hydrogen, ammonia, and the oxidizer nitrous oxide are generated within the waste tanks. Many of these tanks are known to retain and periodically release quantities of these flammable gas mixtures. The primary focus of the Flammable Gas Project is the safe storage of Hanford tank wastes. To this end, we strive to develop an understanding of the mechanisms of flammable gas retention and release in Hanford tanks through laboratory investigations on actual tank wastes. These results support the closure of the Flammable Gas Unreviewed Safety Question (USQ) on the safe storage of waste tanks known to retain flammable gases and support resolution of the broader Flammable Gas Safety Issue. The overall purpose of this ongoing study is to develop a comprehensive and thorough understanding of the mechanisms of flammable gas retention and release. The first objective of the current study was to classify bubble retention and release mechanisms in two previously untested waste materials from Tanks 241-AN-103 (AN-103) and 241-AW-101 (AW-101). Results were obtained for retention mechanisms, release characteristics, and the maximum gas retention. In addition, unique behavior was also documented and compared with previously studied waste samples. The second objective was to lengthen the duration of the experiments to evaluate the role of slowing bubble growth on the retention and release behavior. Results were obtained for experiments lasting from a few hours to a few days

  17. RETENTION TIME EFFECT ON METAL REMOVAL BY PEAT COLUMNS

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, E

    2007-02-28

    The potential use of a peat bed to treat the H-12 Outfall discharge to bring it to new compliance limits was previously investigated and reported utilizing a 7 hour retention time. The influence of retention time (contact time) of water with peat moss on the removal of copper from the water was investigated under laboratory conditions using vertical flow peat moss columns. Reduction of the necessary retention time has a large influence on the design sizing of any peat bed that would be constructed to treat the H-12 discharge on a full scale basis. Retention times of 5 hours, 3 hours and 1 hour were tested to determine the copper removal by the peat columns using vertical flow. Water samples were collected after 4, 8, 12, and 16 water volumes had passed through the columns and analyzed for a suite of metals, with quantitative emphasis on copper. Laboratory results indicated that copper removal was very high at each of the 3 retention times tested, ranging from 99.6 % removal at 5 and 3 hours to 98.8% removal at 1 hour. All these values are much lower that the new compliance limit for the outfall. The results also indicated that most divalent metals were removed to their normal reporting detection limit for the analytical methods used, including zinc. Lead levels in the H-12 discharge used in this study were below PQL in all samples analyzed. While each of the retention times studied removed copper very well, there were indications that 1 hour is probably too short for an operational, long-term facility. At that retention time, there was about 6% compaction of the peat in the column due to the water velocity, and this may affect long term hydraulic conductivity of the peat bed. At that retention time, copper concentration in the effluent was higher than the other times tested, although still very low. Because of the potential compacting and somewhat reduced removal efficiency at a 1 hour retention time, it would be prudent to design to at least a 3 hour retention

  18. Retention of long-term interim restorations with sodium fluoride enriched interim cement

    Science.gov (United States)

    Strash, Carolyn

    Purpose: Interim fixed dental prostheses, or "provisional restorations", are fabricated to restore teeth when definitive prostheses are made indirectly. Patients undergoing extensive prosthodontic treatment frequently require provisionalization for several months or years. The ideal interim cement would retain the restoration for as long as needed and still allow for ease of removal. It would also avoid recurrent caries by preventing demineralization of tooth structure. This study aims to determine if adding sodium fluoride varnish to interim cement may assist in the retention of interim restorations. Materials and methods: stainless steel dies representing a crown preparation were fabricated. Provisional crowns were milled for the dies using CAD/CAM technology. Crowns were provisionally cemented onto the dies using TempBond NE and NexTemp provisional cements as well as a mixture of TempBond NE and Duraphat fluoride varnish. Samples were stored for 24h then tested or thermocycled for 2500 or 5000 cycles before being tested. Retentive strength of each cement was recorded using a universal testing machine. Results: TempBond NE and NexTemp cements performed similarly when tested after 24h. The addition of Duraphat significantly decreased the retention when added to TempBond NE. NexTemp cement had high variability in retention over all tested time periods. Thermocycling for 2500 and 5000 cycles significantly decreased the retention of all cements. Conclusions: The addition of Duraphat fluoride varnish significantly decreased the retention of TempBond NE and is therefore not recommended for clinical use. Thermocycling significantly reduced the retention of TempBond NE and NexTemp. This may suggest that use of these cements for three months, as simulated in this study, is not recommended.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Landry Michel D

    2008-12-01

    Full Text Available Abstract 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

  1. Interlaboratory comparison of the measurement of retention curves

    DEFF Research Database (Denmark)

    Hansen, M. H.; Houvenaghel, G.; Janz, M.

    1999-01-01

    The results of an interlaboratory comparison of the measurement of apparent density, solid density, open porosity and retention curves are presented. Baumberger sandstone and Sander sandstone were used as test materials.Repeatability standard deviation and reproducibility standard deviation...

  2. Process for retention of iodine and aerosols during containment venting

    International Nuclear Information System (INIS)

    Eckardt, B.; Betz, R.; Greger, G.U.; Werner, K.D.

    1990-05-01

    A process for retention of the majority of aerosols and iodine during containment venting was optimized. For this purpose, sections of a two-stage process comprising a venturi scrubber and a metal-fiber filter demister were tested under containment venting conditions assumed to prevail during a hypothetical core - melt accident and optimized with a view to achieving high decontamination factors and loading capacity while minimizing the size of the process. The loading and retention tests performed in a scrubber operating pressure range between 1 and 10 bar, at temperatures from 50 to 200degC (also boiling pools) and in air and steam atmospheres. Under these unfavorable conditions for aerosol retention, the retention efficiencies were determined at various flow rates with soluble and non-soluble aerosols as well as gaseous iodine. The retention efficiencies for BaSO 4 , uranine and SnO 2 aerosols were determined to be 99.95% to 99.99% for venturi scrubbers with metal-fiber filter demister. The retention efficiency for elemental iodine was determined to be ≄99% including revolatization effects over a 24-hour operating period. The high loading capacity of the venturi scrubber unit was verified after process modifications with various aerosols. The use of full-scale process section together with the best possible simulation of containment venting conditions by the test parameters ensured that the results can be transferred to real venting equipment. The aim of ensuring the retention of the majority of the aerosol-borne activity and of elemental iodine activity and minimizing the process size was clearly achieved and verified by means of this optimized venting equipment under an extremely wide range of hypothetical core-melt accident conditions. (orig.) With 17 refs., 3 tabs., 35 annexes [de

  3. Ice-condenser aerosol tests

    International Nuclear Information System (INIS)

    Ligotke, M.W.; Eschbach, E.J.; Winegardner, W.K.

    1991-09-01

    This report presents the results of an experimental investigation of aerosol particle transport and capture using a full-scale height and reduced-scale cross section test facility based on the design of the ice compartment of a pressurized water reactor (PWR) ice-condenser containment system. Results of 38 tests included thermal-hydraulic as well as aerosol particle data. Particle retention in the test section was greatly influenced by thermal-hydraulic and aerosol test parameters. Test-average decontamination factor (DF) ranged between 1.0 and 36 (retentions between ∌0 and 97.2%). The measured test-average particle retentions for tests without and with ice and steam ranged between DF = 1.0 and 2.2 and DF = 2.4 and 36, respectively. In order to apparent importance, parameters that caused particle retention in the test section in the presence of ice were steam mole fraction (SMF), noncondensible gas flow rate (residence time), particle solubility, and inlet particle size. Ice-basket section noncondensible flows greater than 0.1 m 3 /s resulted in stable thermal stratification whereas flows less than 0.1 m 3 /s resulted in thermal behavior termed meandering with frequent temperature crossovers between flow channels. 10 refs., 66 figs., 16 tabs

  4. Retention in medication-assisted treatment programs in Ukraine-Identifying factors contributing to a continuing HIV epidemic.

    Science.gov (United States)

    Dumchev, Kostyantyn; Dvoryak, Sergii; Chernova, Olena; Morozova, Olga; Altice, Frederick L

    2017-10-01

    Opioid agonist treatments (OAT) are widely-used, evidence-based strategies for treating opioid dependence and reducing HIV transmission. The positive benefits of OAT are strongly correlated with time spent in treatment, making retention a key indicator for program quality. This study assessed patient retention and associated factors in Ukraine, where OAT was first introduced in 2004. Data from clinical records of 2916 patients enrolled in OAT at thirteen sites from 2005 to 2012 were entered into an electronic monitoring system. Survival analysis methods were used to determine the probability of retention and its correlates. Twelve-month retention was 65.8%, improving from 27.7% in 2005, to 70.9% in 2011. In multivariable analyses, the correlates of retention were receiving medium and high doses of medication (compared to low doses, dropout aHR=0.57 for both medium and high doses), having not been tested for HIV and tuberculosis (compared to not being tested, dropout aHR=4.44 and 3.34, respectively), and among those who were tested-a negative TB test result (compared to receiving a positive test result, dropout aHR=0.67). Retention in Ukrainian OAT programs, especially in recent years, is comparable to other countries. The results confirm the importance of adequate OAT dosing (≄60mg of methadone, ≄8mg of buprenorphine). Higher dosing, however, will require interventions that address negative attitudes toward OAT by patients and providers. Interruption of OAT, in the case developing tuberculosis, should incorporate continuity of OAT for TB patients through integrated care delivery systems. Copyright © 2017 Elsevier B.V. All rights reserved.

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

    Science.gov (United States)

    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.

  6. Effect of Methylphenidate on Retention and Retrieval of Passive Avoidance Memory in Young and Aged Mice

    Directory of Open Access Journals (Sweden)

    Arzi

    2014-10-01

    Full Text Available Background Several studies showed that dopamine and norepinephrine improve retention and retrieval of memory. Methylphenidate is an enhancer of dopamine and norepinephrine in brain. Objectives In the present study, the effect of methylphenidate was evaluated on retention and retrieval of memory in young and aged mice using passive avoidance apparatus. Materials and Methods Animals were divided into groups (n = 8 as follows: test groups received electric shock plus methylphenidate (2.5, 5 and 10mg kg-1, i. P., control group received electric shock plus normal saline and blank group received only electric shock. In all groups, step-down latency for both retention and retrieval test of memory was measured. Methylphenidate was administered immediately after receiving electric shock in the retention test, but methylphenidate was administered 23.5 hours after receiving electric shock in the retrieval test. Results The mean of step-down latency on day 4 was significantly higher compared to day 2 (P < 0.05 in all young and aged groups of mice. The best response was attained with 5 mg/kg of methylphenidate. In memory retention test, the mean of step-down latency in young groups that received 2.5 and 5 mg/kg methylphenidate was significantly longer(P < 0.05 than aged groups. However, this difference was not significant in memory retrieval test. Conclusions Methylphenidate may improve memory retention and retrieval.

  7. Impact of systematic HIV testing on case finding and retention in care at a primary care clinic in South Africa.

    Science.gov (United States)

    Clouse, Kate; Hanrahan, Colleen F; Bassett, Jean; Fox, Matthew P; Sanne, Ian; Van Rie, Annelies

    2014-12-01

    Systematic, opt-out HIV counselling and testing (HCT) may diagnose individuals at lower levels of immunodeficiency but may impact loss to follow-up (LTFU) if healthier people are less motivated to engage and remain in HIV care. We explored LTFU and patient clinical outcomes under two different HIV testing strategies. We compared patient characteristics and retention in care between adults newly diagnosed with HIV by either voluntary counselling and testing (VCT) plus targeted provider-initiated counselling and testing (PITC) or systematic HCT at a primary care clinic in Johannesburg, South Africa. One thousand one hundred and forty-four adults were newly diagnosed by VCT/PITC and 1124 by systematic HCT. Two-thirds of diagnoses were in women. Median CD4 count at HIV diagnosis (251 vs. 264 cells/Όl, P = 0.19) and proportion of individuals eligible for antiretroviral therapy (ART) (67.2% vs. 66.7%, P = 0.80) did not differ by HCT strategy. Within 1 year of HIV diagnosis, half were LTFU: 50.5% under VCT/PITC and 49.6% under systematic HCT (P = 0.64). The overall hazard of LTFU was not affected by testing policy (aHR 0.98, 95%CI: 0.87-1.10). Independent of HCT strategy, males, younger adults and those ineligible for ART were at higher risk of LTFU. Implementation of systematic HCT did not increase baseline CD4 count. Overall retention in the first year after HIV diagnosis was low (37.9%), especially among those ineligible for ART, but did not differ by testing strategy. Expansion of HIV testing should coincide with effective strategies to increase retention in care, especially among those not yet eligible for ART at initial diagnosis. © 2014 John Wiley & Sons Ltd.

  8. 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.

    Science.gov (United States)

    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

  9. A facility specialist model for improving retention of nursing home staff: results from a randomized, controlled study.

    Science.gov (United States)

    Pillemer, Karl; Meador, Rhoda; Henderson, Charles; Robison, Julie; Hegeman, Carol; Graham, Edwin; Schultz, Leslie

    2008-07-01

    This article reports on a randomized, controlled intervention study designed to reduce employee turnover by creating a retention specialist position in nursing homes. We collected data three times over a 1-year period in 30 nursing homes, sampled in stratified random manner from facilities in New York State and Connecticut and randomly assigned to treatment and control conditions. Staff outcomes were measured through certified nursing assistant interviews, and turnover rates were measured over the course of the year. In the intervention condition, a staff member was selected to be the facility retention specialist, who would advocate for and implement programs to improve staff retention and commitment throughout the facility. Retention specialists received an intensive 3-day training in retention leadership and in a number of evidence-based retention programs. Ongoing support was provided throughout the project. Treatment facilities experienced significant declines in turnover rates compared to control facilities. As predicted, we found positive effects on certified nursing assistant assessments of the quality of retention efforts and of care provided in the facility; we did not find effects for job satisfaction or stress. The study provides evidence for the effectiveness of the retention specialist model. Findings from a detailed process evaluation suggest modifications of the program that may increase program effects.

  10. Environmental Effects on Data Retention in Flash Cells

    Science.gov (United States)

    Katz, Rich; Flowers, David; Bergevin, Keith

    2017-01-01

    Flash technology is being utilized in fuzed munition applications and, based on the development of digital logic devices in the commercial world, usage of flash technology will increase. Antifuse technology, prevalent in non-volatile field programmable gate arrays (FPGAs), will eventually be phased out as new devices have not been developed for approximately a decade. The reliance on flash technology presents a long-term reliability issue for both DoD and NASA safety- and mission-critical applications. A thorough understanding of the data retention failure modes and statistics associated with Flash data retention is of vital concern to the fuze safety community. A key retention parameter for a flash cell is the threshold voltage (VTH), which is an indirect indicator of the amount of charge stored on the cells floating gate. This paper will present the results of our on-going tests: long-term storage at 150 C for a small population of devices, neutron radiation exposure, electrostatic discharge (ESD) testing, and the trends of large populations (over 300 devices for each condition) exposed to three difference temperatures: 25 C, 125 C, and 150 C.

  11. Strategies to improve retention in randomised trials

    Science.gov (United States)

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

    2013-01-01

    LANGUAGE SUMMARY Methods that might help to keep people in randomised trials Background Most trials follow people up to collect data through personal contact after they have been recruited. Some trials get data from other sources, such as routine collected data or disease registers. There are many ways to collect data from people in trials, and these include using letters, the internet, telephone calls, text messaging, face-to-face meetings or the return of medical test kits. Most trials have missing data, for example, because people are too busy to reply, are unable to attend a clinic, have moved or no longer want to participate. Sometimes data has not been recorded at study sites, or are not sent to the trial co-ordinating centre. Researchers call this 'loss to follow-up', 'drop out' or 'attrition' and it can affect the trial's results. For example, if the people with the most or least severe symptoms do not return questionnaires or attend a follow-up visit, this will bias the findings of the trial. Many methods are used by researchers to keep people in trials. These encourage people to send back data by questionnaire, return to a clinic or hospital for trial-related tests, or be seen by a health or community care worker. Study characteristics This review identified methods that encouraged people to stay in trials. We searched scientific databases for randomised studies (where people are allocated to one of two or more possible treatments in a random manner) or quasi-randomised studies (where allocation is not really random, e.g. based on date of birth, order in which they attended clinic) that compared methods of increasing retention in trials. We included trials of participants from any age, gender, ethnic, cultural, language and geographic groups. Key results The methods that appeared to work were offering or giving a small amount of money for return of a completed questionnaire and enclosing a small amount of money with a questionnaire with the promise of a further

  12. The Effects of Different Doses of Curcuma longa Aqueous Extract on Memory Retention and Retrieval in Male Mice

    Directory of Open Access Journals (Sweden)

    2016-12-01

    Full Text Available Background and Objectives: Curcumin belongs to ginger family, which is used as food and drug from ancient times. Different studies have shown beneficial effects of curcumin on peptic ulcer, rheumatoid arthritis, asthma, and various types of cancer. In this study, the effect of different doses of Curcuma longa aqueous extract on memory retention and retrieval of mice, was investigated using passive avoidance apparatus. Methods: Mice were divided into 6 groups of 8 each for memory retention test and 6 groups of 8 each for memory retrieval test {experimental groups receiving the extract intraperitoneally at doses of 100, 200, 400, 800mg/kg, blank group, and control group}. In memory retention test, the curcumin extract was administered immediately after electric shock, while in the memory retrieval test, it was administered 24 h after receiving electric shock. To compare the complete stepping in the experiment days, One-way ANOVA and post-test LSD were used. The level of significance was considered p<0.05. Results: In this study, curcuma longa aqueous extract significantly increased memory retention and retrieval on the 4th day compared to blank and control groups. The best response for memory retention was obtained at the dose of 100mg/kg and for memory retrieval at the dose of 200mg/kg. Conclusion: According to the results of this study, it seems that Curcuma longa aqueous extract improves memory retention and retrieval in healthy mice.  

  13. Practicing more retrieval routes leads to greater memory retention.

    Science.gov (United States)

    Zheng, Jun; Zhang, Wei; Li, Tongtong; Liu, Zhaomin; Luo, Liang

    2016-09-01

    A wealth of research has shown that retrieval practice plays a significant role in improving memory retention. The current study focused on one simple yet rarely examined question: would repeated retrieval using two different retrieval routes or using the same retrieval route twice lead to greater long-term memory retention? Participants elaborately learned 22 Japanese-Chinese translation word pairs using two different mediators. Half an hour after the initial study phase, the participants completed two retrieval sessions using either one mediator (Tm1Tm1) or two different mediators (Tm1Tm2). On the final test, which was performed 1week after the retrieval practice phase, the participants received only the cue with a request to report the mediator (M1 or M2) followed by the target (Experiment 1) or only the mediator (M1 or M2) with a request to report the target (Experiment 2). The results of Experiment 1 indicated that the participants who practiced under the Tm1Tm2 condition exhibited greater target retention than those who practiced under the Tm1Tm1 condition. This difference in performance was due to the significant disadvantage in mediator retrieval and decoding of the unpracticed mediator under the Tm1Tm1 condition. Although mediators were provided to participants on the final test in Experiment 2, decoding of the unpracticed mediators remained less effective than decoding of the practiced mediators. We conclude that practicing multiple retrieval routes leads to greater memory retention than focusing on a single retrieval route. Thus, increasing retrieval variability during repeated retrieval practice indeed significantly improves long-term retention in a delay test. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Experimental results on mechanisms of action of electrical neuromodulation in chronic urinary retention.

    Science.gov (United States)

    Schultz-Lampel, D; Jiang, C; Lindström, S; ThĂŒroff, J W

    1998-01-01

    Sacral foramen neuromodulation--initially applied for the treatment of urinary incontinence--has proved to be effective in patients with chronic urinary retention. Thus far, the underlying neurophysiological mechanisms have not been elucidated. In an experimental study on the neurophysiological basis of sacral neurostimulation, one objective was to investigate the mechanisms responsible for initiation of micturition in chronic urinary retention. In ten female cats anesthetized with alpha-chloralose the clinical situation of sacral foramen stimulation was experimentally reproduced by isolated S2 nerve stimulation after L6-S3 laminectomy. Stimulation responses were recorded from the bladder, peripheral nerves, and striated muscles of the foot and pelvic floor. The effect of sudden cessation of prolonged S2 stimulation, during which the bladder was completely inhibited, was evaluated in 70 stimulation sequences in 5 cats. Sacral nerve stimulation induced excitatory and inhibitory effects on the bladder, depending on the frequency and intensity of stimulation. With unilateral S2 stimulation, bladder excitation was best at frequencies of 2-5 Hz and at intensities ranging between 0.8 and 1.4 times the threshold for the M-response of the foot muscle. Inhibition was the dominating effect at frequencies of 7-10 Hz and at intensities exceeding 1.4 times the threshold. Prolonged S2 stimulation above the threshold produced complete bladder inhibition during stimulation but induced strong bladder contractions after sudden interruption of stimulation, with amplitudes being significantly higher than that of spontaneous contractions preceding the stimulation. These results confirm the hypothesis of a "rebound" phenomenon as the mechanism of action for induction of spontaneous voiding in patients with chronic urinary retention.

  15. Motor skill learning, retention, and control deficits in Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Lisa Katharina Pendt

    Full Text Available Parkinson's disease, which affects the basal ganglia, is known to lead to various impairments of motor control. Since the basal ganglia have also been shown to be involved in learning processes, motor learning has frequently been investigated in this group of patients. However, results are still inconsistent, mainly due to skill levels and time scales of testing. To bridge across the time scale problem, the present study examined de novo skill learning over a long series of practice sessions that comprised early and late learning stages as well as retention. 19 non-demented, medicated, mild to moderate patients with Parkinson's disease and 19 healthy age and gender matched participants practiced a novel throwing task over five days in a virtual environment where timing of release was a critical element. Six patients and seven control participants came to an additional long-term retention testing after seven to nine months. Changes in task performance were analyzed by a method that differentiates between three components of motor learning prominent in different stages of learning: Tolerance, Noise and Covariation. In addition, kinematic analysis related the influence of skill levels as affected by the specific motor control deficits in Parkinson patients to the process of learning. As a result, patients showed similar learning in early and late stages compared to the control subjects. Differences occurred in short-term retention tests; patients' performance constantly decreased after breaks arising from poorer release timing. However, patients were able to overcome the initial timing problems within the course of each practice session and could further improve their throwing performance. Thus, results demonstrate the intact ability to learn a novel motor skill in non-demented, medicated patients with Parkinson's disease and indicate confounding effects of motor control deficits on retention performance.

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

    Science.gov (United States)

    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.

  17. Enhancing retention of partial dentures using elastomeric retention rings

    Directory of Open Access Journals (Sweden)

    Kakkirala Revathi

    2015-01-01

    Full Text Available This report presents an alternative method for the retention of partial dentures that relies on the engagement of tooth undercuts by a lining material. The lab procedures are also presented. A new maxillary and mandibular acrylic partial dentures were fabricated using elastomeric retention technique for a partially dentate patient. A partially dentate man reported difficulty in retaining his upper removable partial denture (RPD. The maxillary RPD was designed utilizing elastomeric retention technique. During follow-up, it was necessary to replace the retention rings due to wear. The replacement of the retention rings, in this case, was done through a chairside reline technique. Elastomeric retention technique provides exceptionally good retention can be indicated to stabilize, cushion, splint periodontally involved teeth, no enough undercut for clasps, eliminate extractions, single or isolated teeth.

  18. The effect of soy products in the diet on retention of non-heme iron from radiolabeled test meals fed to marginally iron-deficient young rats

    International Nuclear Information System (INIS)

    Thompson, D.B.

    1984-01-01

    Diets based either on casein or soy products and containing about 25 ppm iron were fed to weanling rats for 13 days. Rats were fasted overnight and fed a 59 Fe-radiolabeled casein test meal the morning of day 14. On day 21 less 59 Fe was retained by rats fed various diets based on selected soy products than by rats fed the casein-based diet. A similar adverse effect of diet components on 59 Fe retention from a casein test meal was observed for lactalbumin and for psyllium husk. No adverse effect of diet on 59 Fe retention was observed for the fiber of soy cotyledons or for rapeseed protein concentrate. For a commercial soy protein isolated (SPI) fed throughout the 21-day experiment, the adverse effect of diet on 59 Fe retention was observed to the sum of the effect of dietary SPI previous to the 59 Fe-radiolabeled casein test meal fed on day 14 and the effect of dietary SPI subsequent to the casein test meal. An effect of dietary soy products on 59 Fe retention from a casein test meal was not observed with diets containing higher iron levels (83 ppm) or when diets were fed for a longer period prior to the test meal (56 days). The present work shows that in some circumstances the concept of iron bioavailability must be expanded to include not only the influence of meal composition, but also the influence of diet previous to and subsequent to a meal

  19. Retention of anatomy knowledge by student radiographers

    International Nuclear Information System (INIS)

    Hall, A. Susanne; Durward, Brian R.

    2009-01-01

    Introduction: Anatomy has long been regarded as an integral part of the core curriculum. However, anecdotal evidence suggests that long-term retention of anatomy knowledge may be deficient. This study aims to evidence whether student radiographers demonstrate the same level of knowledge of anatomy after a period of time has elapsed and to correlate to approaches to learning and studying. Methodology: A repeated measures design was utilised to measure retention of anatomy knowledge for both MCQs and short-response answers to a Practical Radiographic Anatomy Examination; alpha value p < 0.05. Fifty-one students from levels 2 and 3 were retested after a time lapse of 10 and 22 months respectively. The students were not aware that their knowledge was being retested. Approaches to learning and studying were measured using the ASSIST inventory. Results: Statistical analysis found no difference in performance on MCQ assessment, in either the combined sample or levels 2 and 3 separately, from baseline to retention occasions; average retention rate being 99%. However, a statistical difference in performance on PRAE assessment was found, with level 2 experiencing a larger reduction in scores; retention rate of 67% compared to level 3 at 77%. The students perceived themselves to be principally strategic in their approach to learning and studying but no strong relationships were found when correlated to test scores. Conclusion: The student radiographers in this study demonstrated varied anatomy retention rates dependent on assessment method employed and time interval that had elapsed. It is recommended that diverse teaching and assessment strategies are adopted to encourage a deeper approach to learning and studying.

  20. The Effects of Long-Duration Spaceflight on Training Retention and Transfer

    Science.gov (United States)

    Barshi, Immanuel; Healy, Alice; Dempsey, Donna L.; McGuire, Kerry M.; Landon, Lauren B.

    2018-01-01

    Training our crew members for long duration, exploration-class missions will have to maximize long-term retention and transfer of the trained skills. The expected duration of the missions, our inability to predict all the possible tasks the crew will be called upon to perform, and the low training-to-mission time ratio require that the training be maximally effective such that the skills acquired during training will be retained and will be transferrable across a wide range of specific tasks that are different from the particular tasks used during training. However, to be able to design training that can achieve these ambitious goals, we must first understand the ways in which long-duration spaceflight affects training retention and transfer. Current theories of training retention and transfer are largely based on experimental studies conducted at university laboratories using undergraduate students as participants. Furthermore, all such studies have been conducted on Earth. We do not know how well the results of these studies predict the performance of crew members. More specifically, we do not know how well the results of these studies predict the performance of crew members in space and especially during long-duration missions. To address this gap in our knowledge, the current on-going study seeks to test the null hypothesis that performance of university undergraduate students on Earth on training retention and transfer tests do in fact predict accurately the performance of crew members during long-duration spaceflights. To test this hypothesis, the study employs a single 16-month long experimental protocol with 3 different participant groups: undergraduate university students, crew members on the ground, and crew members in space. Results from this study will be presented upon its completion. This poster presents results of study trials of the two tasks used in this study: a data entry task and a mapping task. By researching established training principles, by

  1. Social Media Interventions to Promote HIV Testing, Linkage, Adherence, and Retention: Systematic Review and Meta-Analysis

    Science.gov (United States)

    Gupta, Somya; Wang, Jiangtao; Hightow-Weidman, Lisa B; Muessig, Kathryn E; Tang, Weiming; Pan, Stephen; Pendse, Razia; Tucker, Joseph D

    2017-01-01

    Background Social media is increasingly used to deliver HIV interventions for key populations worldwide. However, little is known about the specific uses and effects of social media on human immunodeficiency virus (HIV) interventions. Objective This systematic review examines the effectiveness of social media interventions to promote HIV testing, linkage, adherence, and retention among key populations. Methods We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and Cochrane guidelines for this review and registered it on the International Prospective Register of Systematic Reviews, PROSPERO. We systematically searched six databases and three conference websites using search terms related to HIV, social media, and key populations. We included studies where (1) the intervention was created or implemented on social media platforms, (2) study population included men who have sex with men (MSM), transgender individuals, people who inject drugs (PWID), and/or sex workers, and (3) outcomes included promoting HIV testing, linkage, adherence, and/or retention. Meta-analyses were conducted by Review Manager, version 5.3. Pooled relative risk (RR) and 95% confidence intervals were calculated by random-effects models. Results Among 981 manuscripts identified, 26 studies met the inclusion criteria. We found 18 studies from high-income countries, 8 in middle-income countries, and 0 in low-income countries. Eight were randomized controlled trials, and 18 were observational studies. All studies (n=26) included MSM; five studies also included transgender individuals. The focus of 21 studies was HIV testing, four on HIV testing and linkage to care, and one on antiretroviral therapy adherence. Social media interventions were used to do the following: build online interactive communities to encourage HIV testing/adherence (10 studies), provide HIV testing services (9 studies), disseminate HIV information (9 studies), and develop

  2. Student Mental Models of the Greenhouse Effect: Retention Months After Interventions

    Science.gov (United States)

    Harris, S. E.; Gold, A. U.

    2013-12-01

    , there was also no difference in scores based on which contrasting lesson a student did. Students in both of the contrasting lessons scored significantly higher on the retention test than on the initial pre-test. Their concept sketch scores on the retention test were slightly lower than their scores on the final exam (not significantly), but matched their post-lesson-sequence scores. Their MCQ scores were slightly higher on the retention test than on the post-lesson-sequence test (also not significantly). These results imply that students both learned and retained new ideas about the greenhouse effect for at least a few months after the end of the course and did not regress to their pre-lesson ideas. Further analysis should show which particular aspects of student mental models changed over the full temporal sequence.

  3. Predictors of retention in a multicomponent treatment for smokers

    Directory of Open Access Journals (Sweden)

    Ana Moreno-Coutiño

    Full Text Available Abstract Background: There is a lack of knowledge about factors that promote or hinder retention of smokers in treatment. Objective: The aim of this study was the identification of variables that predict retention of smokers who received a multicomponent treatment against smoking. Method: Participants (n = 79 simultaneously received pharmacological and psychological treatment, including an intervention phase prior to the date of smoking cessation. They were evaluated periodically in their abstinence, depressive and anxious symptoms, and were randomly assigned to three treatment conditions (nicotine patch, bupropion or nicotine patch + bupropion. Eighteen variables were grouped into four categories (demographic, consumption pattern, mood and treatment. Data were analyzed using student's t test and X2, for inclusion into a multivariate logistic regression model. Results: Results indicate that age of onset of regular tobacco consumption, secondary education and bupropion pharmacological treatment are significant in relation to the retention of smokers to smoking treatment. Discussion: The reported “age of onset” correlates with treatment retention (OR = 1.545, 95 % CI = 1.175-2.032. This variable has not previously been reported in the literature, and taking it into account in the design of prevention and treatment for smoking could increase their success.

  4. Divided attention: an undesirable difficulty in memory retention.

    Science.gov (United States)

    Gaspelin, Nicholas; Ruthruff, Eric; Pashler, Harold

    2013-10-01

    How can we improve memory retention? A large body of research has suggested that difficulty encountered during learning, such as when practice sessions are distributed rather than massed, can enhance later memory performance (see R. A. Bjork & E. L. Bjork, 1992). Here, we investigated whether divided attention during retrieval practice can also constitute a desirable difficulty. Following two initial study phases and one test phase with Swahili-English word pairs (e.g., vuvi-snake), we manipulated whether items were tested again under full or divided attention. Two days later, participants were brought back for a final cued-recall test (e.g., vuvi-?). Across three experiments (combined N = 122), we found no evidence that dividing attention while practicing retrieval enhances memory retention. This finding raises the question of why many types of difficulty during practice do improve long-term retention, but dividing attention does not.

  5. Plasma wall interaction and tritium retention in TFTR

    International Nuclear Information System (INIS)

    Skinner, C.H.; Amarescu, E.; Ascione, G.

    1996-01-01

    The Tokamak Fusion Test Reactor (TFTR) has been operating safely and routinely with deuterium-tritium fuel for more than two years. In this time, TFTR has produced an impressive number of record breaking results including core fusion power, ∌ 2 MW/m 3 , comparable to that expected for ITER. Advances in wall conditioning via lithium pellet injection have played an essential role in achieving these results. Deuterium-tritium operation has also provided a special opportunity to address the issues of tritium recycling and retention. Tritium retention over two years of operation was approximately 40%. Recently, the in-torus tritium inventory was reduced by half through a combination of glow discharge cleaning, moist-air soaks, and plasma discharge cleaning. The tritium inventory is not a constraint in continued operations. The authors present recent results from TFTR in the context of plasma wall interactions and deuterium-tritium issues

  6. Plasma wall interaction and tritium retention in TFTR

    International Nuclear Information System (INIS)

    Skinner, C.H.; Amarescu, E.; Ascione, G.

    1997-01-01

    The Tokamak Fusion Test Reactor (TFTR) has been operating safely and routinely with deuterium-tritium fuel for more than two years. In this time, TFTR has produced a number of record breaking results including core fusion power, ∝2 MW/m 3 , comparable to that expected for ITER. Advances in wall conditioning via lithium pellet injection have played an essential role in achieving these results. Deuterium-tritium operation has also provided a special opportunity to address the issues of tritium recycling and retention. Tritium retention over two years of operation was approximately 40%. Recently the in-torus tritium inventory was reduced by half through a combination of glow discharge cleaning, moist-air soaks, and plasma discharge cleaning. The tritium inventory is not a constraint in continued operations. Recent results from TFTR in the context of plasma wall interactions and deuterium-tritium issues are presented. (orig.)

  7. National Survey Results: Retention of Women in Collegiate Aviation

    Science.gov (United States)

    Turney, Mary Ann; Bishop, James C.; Karp, Merrill R.; Niemczyk, Mary; Sitler, Ruth L.; Green, Mavis F.

    2002-01-01

    Since the numbers of women pursuing technical careers in aviation continues to remain very low, a study on retention of women was undertaken by a team of university faculty from Embry Riddle Aeronautical University, Arizona State University, and Kent State University. The study was initiated to discover the factors that influence women once they have already selected an aviation career and to ascertain what could be done to support those women who have demonstrated a serious interest in an aviation career by enrolling in a collegiate aviation program. This paper reports preliminary results of data collected in the first and second years of the study. The data was collected from surveys of 390 college students (195 women and 195 men) majoring in aviation programs in nine colleges and universities, representing widely varied geographic areas and including both two- and four-year institutions. Results revealed significant areas of concern among women in pilot training. When queried about these concerns, differences were evident in the responses of the male and female groups. These differences were expected. However, a surprising finding was that women in early stages of pilot training responded differently from women in more experienced stages, These response differences did not occur among the men surveyed. The results, therefore, suggest that women in experienced stages of training may have gone through an adaptation process and reflect more male-like attitudes about a number of objects, including social issues, confidence, family, and career.

  8. Retentiveness of implant-supported metal copings using different luting agents

    Directory of Open Access Journals (Sweden)

    Farahnaz Nejatidanesh

    2012-01-01

    Full Text Available Background: With regard to potential retrievability of cement-retained implant restorations, the retentive strength of the luting agents is critical. The aim of this study was to evaluate the retention values of implant-supported metal copings using different luting agents. Materials and Methods: Twenty ITI implant analogs and solid abutments of 5.5-mm height were embedded vertically in autopolymerizing acrylic resin blocks. Metal copings with a loop on the occlusal surface were fabricated using base metal alloy (Rexillium III. The copings were luted using eight cements with different retention mechanisms (Panavia F2.0, Fuji Plus, Fleckâ€Čs, Poly F, Fuji I, Temp Bond, GC-free eugenol, and TempSpan under static load of 5 kg (n=10. All specimens were incubated at 37°C for 24 hours, conditioned in artificial saliva for 7 days and thermocycled for 5000 cycles (5-55°C. The dislodging force was measured using a universal testing machine at a crosshead speed of 5 mm/min. Statistical analyses were performed using Kruskal-Wallis (α=0.05 and Mann-Whitney tests with Bonferroni correction (α=0.001. Results: Fuji Plus and TempSpan had the highest and the least mean retentive strength, respectively (320.97±161.47, 3.39±2.33. There was no significant difference between Fuji Plus, Fleckâ€Čs, Ploy F, and Panavia F2.0. These cements were superior to provisional cements and Fuji I (P<0.001 which showed statistically same retentive strength. Conclusion: Within the conditions of this study, the resin modified glass ionomer, zinc phosphate, zinc polycarboxylate, and Panavia F2.0 had statistically the same retentive quality and are recommended for definitive cementation of single implant-supported restorations. The provisional cements and glass ionomer may allow retrievability of these restorations.

  9. Retention of Root Canal Posts

    DEFF Research Database (Denmark)

    Sahafi, A; Benetti, Ana Raquel; Flury, S

    2015-01-01

    The aim of this study was to investigate the effect of the cement film thickness of a zinc phosphate or a resin cement on retention of untreated and pretreated root canal posts. Prefabricated zirconia posts (CosmoPost: 1.4 mm) and two types of luting cements (a zinc phosphate cement [DeTrey Zinc...... received tribochemical silicate coating according to the manufacturer's instructions. Posts were then luted in the prepared root canals (n=30 per group). Following water storage at 37°C for seven days, retention of the posts was determined by the pull-out method. Irrespective of the luting cement......, pretreatment with tribochemical silicate coating significantly increased retention of the posts. Increased cement film thickness resulted in decreased retention of untreated posts and of pretreated posts luted with zinc phosphate cement. Increased cement film thickness had no influence on retention...

  10. The Effect of Supplemental Instruction on Retention: A Bivariate Probit Model

    Science.gov (United States)

    Bowles, Tyler J.; Jones, Jason

    2004-01-01

    Single equation regression models have been used to test the effect of Supplemental Instruction (SI) on student retention. These models, however, fail to account for the two salient features of SI attendance and retention: (1) both SI attendance and retention are categorical variables, and (2) are jointly determined endogenous variables. Adopting


  11. Evaluation of retentive strength of four luting cements with stainless steel crowns in primary molars: An in vitro study.

    Science.gov (United States)

    Parisay, Iman; Khazaei, Yegane

    2018-01-01

    Stainless steel crown (SSC) is the most reliable restoration for primary teeth with extensive caries. Retention is of great importance for a successful restoration and is provided by various factors such as luting cements. The aim of this study was to evaluate the retentive strength of SSC cemented with four different luting cements. In this in vitro study, A total of 55 extracted primary first molars were selected. Following crown selection and cementation (one with no cement and four groups cemented with resin, glass ionomer, zinc phosphate, and polycarboxylate), all the specimens were incubated and thermocycled in 5°C-55°C. Retentive properties of SSCs were tested with a mechanical test machine. First dislodgement of each specimen and full crown removal were recorded. One-way ANOVA test followed by least significant difference test and Kruskal-Wallis test was used for retentive strength comparison at the level of significance of P cemented with zinc phosphate exhibited higher retentive strength as compared to glass ionomer and polycarboxylate ( P cement showed the most promising results; thus, it can be preferably used for cementation of the teeth with no grossly broken down crowns.

  12. Determination of water retention curves of concrete

    International Nuclear Information System (INIS)

    Villar, M.V.; Romero, F.J.

    2015-01-01

    The water retention curves of concrete and mortar obtained with two different techniques and following wetting and drying paths were determined. The material was the same used to manufacture the disposal cells of the Spanish surface facility of El Cabril. The water retention capacity of mortar is clearly higher than that of concrete when expressed as gravimetric water content, but the difference reduces when it is expressed as degree of saturation. Hysteresis between wetting and drying was observed for both materials, particularly for mortar. The tests went on for very long periods of time, and concerns about the geochemical, mineralogical and porosity changes occurred in the materials during the determinations (changes in dry mass, grain density, samples volume) and their repercussion on the results obtained (water content and degree of saturation computation) were raised. Also, the fact of having used techniques applying total and matrix suction could have affected the results. (authors)

  13. Water retention properties of ashes; Vattenretentionsegenskaper hos aska

    Energy Technology Data Exchange (ETDEWEB)

    Hemstroem, Kristian; Ezziyani, Samir; Bendz, David

    2009-05-15

    The water holding properties of a material can be described with a water retention curve (also called pF curve or characteristic curve). The importance of this material property has until now been neglected in waste and rest products contexts. There is an eminent need for knowledge of the water holding properties of ash and rest products in order to improve the possibility to perform i) assessment of leaching from rest product used in constructions, ii) dimensioning of covers built with rest products and iii) assessment of long term properties of land fill waste concerning leaching, especially for stabilized ash with a monolithic characteristics. The aim of this project was to increase the knowledge of the water holding properties of ashes by determining water retention curves with laboratory methods on four ash materials with the potential to be used in constructions. In the project, four ashes has been studied; one MSWI bottom ash from SYSAV, one aged MSWI bottom ash from Gaerstadverket and two fly ashes from incineration of biofuels; one from SCA Ortviken and one from Jaemtkraft AB. For comparison, data from a silt soil studied in another SGI project is presented. When determining a water retention curve for a specific material water from the examined, beforehand water saturated, sample is eliminated under controlled circumstances in a pressure plate extractor. The sample is exposed to a pressure, with increasing degree, squeezing excess water out of the material. The excess water is measured for each increased pressure step and the remaining volumetric water content in the material can be calculated. The results from such measurements are presented in water retention curves, in which the volumetric water content is plotted as a function of the capillary pressure. The water retention curves shows how various materials differ in water content at the same pressure. The results from the study showed that ashes have great water holding capacity. The study also

  14. Testing the shape-similarity hypothesis between particle-size distribution and water retention for Sicilian soils

    Directory of Open Access Journals (Sweden)

    Chiara Antinoro

    2012-12-01

    Full Text Available Application of the Arya and Paris (AP model to estimate the soil water retention curve requires a detailed description of the particlesize distribution (PSD but limited experimental PSD data are generally determined by the conventional sieve-hydrometer (SH method. Detailed PSDs can be obtained by fitting a continuous model to SH data or performing measurements by the laser diffraction (LD method. The AP model was applied to 40 Sicilian soils for which the PSD was measured by both the SH and LD methods. The scale factor was set equal to 1.38 (procedure AP1 or estimated by a logistical model with parameters gathered from literature (procedure AP2. For both SH and LD data, procedure AP2 allowed a more accurate prediction of the water retention than procedure AP1, confirming that it is not convenient to use a unique value of  for soils that are very different in texture. Despite the differences in PSDs obtained by the SH and LD methods, the water retention predicted by a given procedure (AP1 or AP2 using SH or LD data was characterized by the same level of accuracy. Discrepancies in the estimated water retention from the two PSD measurement methods were attributed to underestimation of the finest diameter frequency obtained by the LD method. Analysis also showed that the soil water retention estimated using the SH method was affected by an estimation bias that could be corrected by an optimization procedure (OPT. Comparison of a-distributions and water retention shape indices obtained by the two methods (SH or LD indicated that the shape-similarity hypothesis is better verified if the traditional sieve-hydrometer data are used to apply the AP model. The optimization procedure allowed more accurate predictions of the water retention curves than the traditional AP1 and AP2 procedures. Therefore, OPT can be considered a valid alternative to the more complex logistical model for estimating the water retention curve of Sicilian soils.

  15. Seed Implant Retention Score Predicts the Risk of Prolonged Urinary Retention After Prostate Brachytherapy

    International Nuclear Information System (INIS)

    Lee, Hoon K.; Adams, Marc T.; Shi, Qiuhu; Basillote, Jay; LaMonica, Joanne; Miranda, Luis; Motta, Joseph

    2010-01-01

    Purpose: To risk-stratify patients for urinary retention after prostate brachytherapy according to a novel seed implant retention score (SIRS). Patients and Methods: A total of 835 patients underwent transperineal prostate seed implant from March 1993 to January 2007; 197 patients had 125 I and 638 patients had 103 Pd brachytherapy. Four hundred ninety-four patients had supplemental external-beam radiation. The final downsized prostate volume was used for the 424 patients who had neoadjuvant hormone therapy. Retention was defined as reinsertion of a Foley catheter after the implant. Results: Retention developed in 7.4% of patients, with an average duration of 6.7 weeks. On univariate analysis, implant without supplemental external-beam radiation (10% vs. 5.6%; p = 0.02), neoadjuvant hormone therapy (9.4% vs. 5.4%; p = 0.02), baseline α-blocker use (12.5% vs. 6.3%; p = 0.008), and increased prostate volume (13.4% vs. 6.9% vs. 2.9%, >45 cm 3 , 25-45 cm 3 , 3 ; p = 0.0008) were significantly correlated with increased rates of retention. On multivariate analysis, implant without supplemental external-beam radiation, neoadjuvant hormone therapy, baseline α-blocker use, and increased prostate volume were correlated with retention. A novel SIRS was modeled as the combined score of these factors, ranging from 0 to 5. There was a significant correlation between the SIRS and retention (p < 0.0001). The rates of retention were 0, 4%, 5.6%, 9%, 20.9%, and 36.4% for SIRS of 0 to 5, respectively. Conclusions: The SIRS may identify patients who are at high risk for prolonged retention after prostate brachytherapy. A prospective validation study of the SIRS is planned.

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

    Directory of Open Access Journals (Sweden)

    Yibeltal Assefa

    Full Text Available INTRODUCTION: 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. METHODS: 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. RESULTS: 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. CONCLUSION: 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.

  17. Aerosol retention in the flooded steam generator bundle during SGTR

    International Nuclear Information System (INIS)

    Lind, Terttaliisa; Dehbi, Abdel; Guentay, Salih

    2011-01-01

    Research highlights: → High retention of aerosol particles in a steam generator bundle flooded with water. → Increasing particle inertia, i.e., particle size and velocity, increases retention. → Much higher retention of aerosol particles in the steam generator bundle flooded with water than in a dry bundle. → Much higher retention of aerosol particles in the steam generator bundle than in a bare pool. → Bare pool models have to be adapted to be applicable for flooded bundles. - Abstract: A steam generator tube rupture in a pressurized water reactor may cause accidental release of radioactive particles into the environment. Its specific significance is in its potential to bypass the containment thereby providing a direct pathway of the radioactivity from the primary circuit to the environment. Under certain severe accident scenarios, the steam generator bundle may be flooded with water. In addition, some severe accident management procedures are designed to minimize the release of radioactivity into the environment by flooding the defective steam generator secondary side with water when the steam generator has dried out. To extend our understanding of the particle retention phenomena in the flooded steam generator bundle, tests were conducted in the ARTIST and ARTIST II programs to determine the effect of different parameters on particle retention. The effects of particle type (spherical or agglomerate), particle size, gas mass flow rate, and the break submergence on particle retention were investigated. Results can be summarized as follows: increasing particle inertia was found to increase retention in the flooded bundle. Particle shape, i.e., agglomerate or spherical structure, did not affect retention significantly. Even with a very low submergence, 0.3 m above the tube break, significant aerosol retention took place underlining the importance of the jet-bundle interactions close to the tube break. Droplets were entrained from the water surface with

  18. Imaging and retention measurements of selenium 75 homocholic acid conjugated with taurine, and the carbon 14 glycochol breath test to document ileal dysfunction due to late radiation damage

    International Nuclear Information System (INIS)

    Valdes Olmos, R.; Hartog Jager, F. den; Hoefnagel, C.; Taal, B.; Netherlands Cancer Inst., Amsterdam

    1991-01-01

    In order to assess ileal dysfunction in patients with complaints after pelvic radiation therapy, retention measurements and scintigraphic imaging with selenium 75 homocholic acid conjugated with taurine ( 75 Se-HCAT), combined with the carbon 14 clycochol breath test, were evaluated in 39 patients. In 22 patients without ileal resection the results of the 75 Se-HCAT test and the breath test differentiated between a normal functioning ileum (both tests negative) and ileal dysfunction as a cause of complaints (one or both tests positive). Among the patients with ileal dysfunction, the combination of both tests permitted those with bacterial overgrowth (breath test positive, 75 Se-HCAT negative) to be separated from patients with evidence of bile acid malabsorption ( 75 Se-HCAT positive, breath test positive or negative). In 17 patients with small-bowel resection, the 75 Se-HCAT test helped to estimate the severity of bile acid malabsorption with implications for therapy. In this group the breath test was false-negative in 7 cases with abnormal 75 Se-HCAT. Additional systematically performed scintigraphic imaging improved the accuracy of the 75 Se-HCAT test, revealing cases with prolonged colonic accumulation of the radiopharmaceutical, causing spurious retention values. In conclusion, assessment of ileal dysfunction by nuclear medicine techniques in post-irradiation conditions provides information about the aetiology and therefore the possibility of adjustment in the clinical management. (orig.)

  19. Attainment and retention of force moderation following laparoscopic resection training with visual force feedback.

    Science.gov (United States)

    Hernandez, Rafael; Onar-Thomas, Arzu; Travascio, Francesco; Asfour, Shihab

    2017-11-01

    Laparoscopic training with visual force feedback can lead to immediate improvements in force moderation. However, the long-term retention of this kind of learning and its potential decay are yet unclear. A laparoscopic resection task and force sensing apparatus were designed to assess the benefits of visual force feedback training. Twenty-two male university students with no previous experience in laparoscopy underwent relevant FLS proficiency training. Participants were randomly assigned to either a control or treatment group. Both groups trained on the task for 2 weeks as follows: initial baseline, sixteen training trials, and post-test immediately after. The treatment group had visual force feedback during training, whereas the control group did not. Participants then performed four weekly test trials to assess long-term retention of training. Outcomes recorded were maximum pulling and pushing forces, completion time, and rated task difficulty. Extreme maximum pulling force values were tapered throughout both the training and retention periods. Average maximum pushing forces were significantly lowered towards the end of training and during retention period. No significant decay of applied force learning was found during the 4-week retention period. Completion time and rated task difficulty were higher during training, but results indicate that the difference eventually fades during the retention period. Significant differences in aptitude across participants were found. Visual force feedback training improves on certain aspects of force moderation in a laparoscopic resection task. Results suggest that with enough training there is no significant decay of learning within the first month of the retention period. It is essential to account for differences in aptitude between individuals in this type of longitudinal research. This study shows how an inexpensive force measuring system can be used with an FLS Trainer System after some retrofitting. Surgical

  20. The Effect of Different Water Temperatures on Retention Loss and Material Degradation of Locator Attachments.

    Science.gov (United States)

    Chiu, Lillian Pui Yuk; Vitale, Nicola Di; Petridis, Haralampos; McDonald, Ailbhe

    2017-08-01

    To examine the changes in Locator attachments after exposure to different water temperatures and cyclic loading. Four groups of pink Locator attachments (3.0 lb. light retention replacement patrix attachments; 10 per group) were soaked for the equivalent of 5 years of use in distilled water at the following temperatures: 20°C, 37°C, 60°C. One group was kept dry to test the effect of water. A universal testing machine was used to measure the retention force of each treated attachment during 5500 insertion and removal cycles, simulating approximately 5 years of use. The results were compared using Kruskal-Wallis one-way ANOVA by ranks. Surface changes of tested attachments were examined using scanning electron microscopy (SEM). The exposure to 60°C water significantly increased the percentage of retention loss in Locator attachments (p < 0.05) compared to the 20°C water group and significantly reduced the final retention force compared to the other groups (p < 0.05). SEM examinations revealed severe cracking and material degradation in Locator attachments after exposure to 60°C water and cyclic loading, which were not evident in other groups. Cracking was observed after exposure to 60˚C water before cyclic loading. Exposure to 60°C water, potentially similar to denture cleansing procedures, could cause cracking in Locator attachments. Cracking is associated with hydrolytic degradation of nylon at 60°C. The change in structure could result in a significant loss of retention. © 2016 by the American College of Prosthodontists.

  1. Operational test report for LERF Basin 242AL-44 integrity test

    International Nuclear Information System (INIS)

    Galioto, T.M.

    1994-01-01

    This operational test report documents the results of LERF operational testing per operational test procedure (OTP) TFPE-WP-0231, ''LERF Basin Integrity Testing.'' The primary purpose of the OTP was to resolve test exceptions generated as a result of TFPE-WP-0184. The TOP was prepared and performed in accordance with WHC-SD-534-OTP-002, ''Operational Test Plan for the 242-A Evaporator Upgrades and the Liquid Effluent Retention Facility.'' WHC-S-086, ''Specification for Operational Testing of the Liquid Effluent Retention Facility, Basin Integrity Testing,'' identified the test requirements and acceptance criteria. The completed, signed-off test procedure is contained in Appendix A. The test log is contained in Appendix B. Section 2.1 describes all the test exceptions written during performance of the Operational Test Procedure. The test revisions generated during the testing are discussed in Section 2.2. The dispositioned test exception forms are contained in Appendix C

  2. Application-Based Crossword Puzzles: Players’ Perception and Vocabulary Retention

    Directory of Open Access Journals (Sweden)

    Dzulfikri Dzulfikri

    2016-09-01

    Full Text Available This study investigates the perceptions of students towards Application-Based Crossword Puzzles and how playing this game can affect the development of vocabulary amongst students. Drawing on Vygostky’s Socio-Cultural Theory which states that the human mind is mediated by cultural artifacts, the nature of this game poses challenges and builds curiosity, allowing players to pay more attention to the words to fill in the boxes which subsequently enhances their retention of vocabulary. This game has very good potential to build positive perceptions and to develop cognition in the linguistic domain of players, i.e. the amount of their vocabulary. In this study, the researcher conducted interviews with eligible or selected student players to find out their perceptions toward this game and administered a vocabulary test to find out how this game had added to the retention in memory of new words acquired by the players from the game. The study findings showed that the participants perceive this game positively and it affects the players’ vocabulary retention positively as indicated by their test results. It is recommended that English teachers consider using Application-Based Crossword Puzzles to help students build their vocabularies especially as part of extracurricular activities.

  3. Prebiotics enhance survival and prolong the retention period of specific probiotic inocula in an in vivo murine model.

    Science.gov (United States)

    Su, P; Henriksson, A; Mitchell, H

    2007-12-01

    To identify novel prebiotics that could be used to maintain persistence of three representative probiotic strains in vivo. Test mice were treated with prebiotics soybean oligosaccharide (SOS), fructooligosaccharide (FOS) or inulin, followed by probiotics Lactobacillus acidophilus LAFTI L10 (L10), Bifidobacterium lactis LAFTI B94 (B94) or Lactobacillus casei L26 LAFTI (L26). Faecal samples were then collected and analysed using selective medium and PCR analysis to determine the presence of the probiotic strains. In contrast to the control groups, in mice fed prebiotics, the survival and retention time of the test probiotics was increased extensively. SOS and FOS prolonged the retention period of L10 from 24 to 30 h. Of the three prebiotics, FOS gave the best result with B94, prolonging the retention period from 3 to > or =10 days. Of the three prebiotics, inulin gave the best result for L26, prolonging the retention period from 2 to > or =6 days. The prebiotics SOS, FOS and inulin significantly enhance survival and prolong the retention period of L10, B94 and L26 in vivo. Our results demonstrate the potential use of FOS, inulin and SOS as prebiotics in conjunction with the probiotic strains L10, B94 and L26 for new synbiotic products.

  4. Improved Customer Churn and Retention Decision Management Using Operations Research Approach

    Directory of Open Access Journals (Sweden)

    Sulaimon Olanrewaju Adebiyi

    2017-01-01

    Full Text Available The relevance of operations research cannot be overemphasized, as it provides the best possible results in any given circumstance, through analysis of operations and the use of scientific method thus, this paper explore the combination of two operations research models (analytic hierarchy process and Markov chain for solving subscribers’ churn and retention problem peculiar to most service firms. A conceptual model for unraveling the problem customer churn and retention decision management was proposed and tested with data on third level analysis of AHP for determining appropriate strategies for customer churn and retention in the Nigeria telecommunication industries. A survey was conducted with 408 subscribers; the sample for the study was selected through multi-stage sampling. Two analytical tools were proposed for the analysis of data. These include: Expert Choice/Excel Solver (using Microsoft Excel and Windows based Quantitative System for Business (WinQSB. This paper plays important role in understanding various strategies for effective churn and retention management and the ranking of churn and retention drivers in order of importance to stakeholders` decision-making. The study provided a framework for understanding the application of AHP and Markov chain for modeling, analysing and proffering solution to problem of churn and retention. The study recommends organizational strategies (corporate, business and functional that reverse the churn alternatives with high priority and equally strengthen service delivery on high priority retention alternatives in order to ensure firms sustainable competitive advantage.

  5. Corrosion behavior of dental alloys used for retention elements in prosthodontics.

    Science.gov (United States)

    Nierlich, Judith; Papageorgiou, Spyridon N; Bourauel, Christoph; HĂŒltenschmidt, Robert; Bayer, Stefan; Stark, Helmut; Keilig, Ludger

    2016-06-01

    The purpose of this study was to investigate the corrosion behavior of 10 different high noble gold-based dental alloys, used for prosthodontic retention elements, according to ISO 10271. Samples of 10 high-noble and noble gold-based dental alloys were subjected to: (i) static immersion tests with subsequent analysis of ion release for eight different elements using mass spectrometry; (ii) electrochemical tests, including open-circuit potential and potentiodynamic scans; and (iii) scanning electron microscopy, followed by energy-dispersive X-ray microscopy. The results were analyzed using one-way ANOVA and Sidak multiple-comparisons post-hoc test at a level of significance of α = 0.05. Significant differences were found among the 10 alloys studied for all ions (P alloys. Scanning electron microscopy analysis confirmed the existence of typically small-diameter corrosion defects, whilst the energy-dispersive X-ray analysis found no significant alteration in the elemental composition of the alloys. The results of this study reveal the variability in the corrosive resistance among the materials used for retention elements in prosthodontics. © 2016 Eur J Oral Sci.

  6. Posttreatment and retention outcomes with and without periodontally accelerated osteogenic orthodontics assessed using ABO objective grading system

    Directory of Open Access Journals (Sweden)

    Donald J Ferguson

    2016-01-01

    Full Text Available Background: The posttreatment and retention outcomes following nonextraction orthodontic therapy, with and without corticotomy, were assessed using the American Board of Orthodontists objective grading system (OGS. Purpose: The purpose was to determine if the course of retention was any different following alveolar decortication and augmentation bone grafting, i.e., periodontally accelerated osteogenic orthodontics (PAOO. Materials and Methods: Study casts and panoramic radiographs of patients with and without PAOO (28 subjects each were selected on the basis of the following: (1 comprehensive nonextraction orthodontic treatment using straight wire edgewise appliances for Class I crowding, (2 availability of immediate posttreatment records and retention records at least 1 year post de-bracketing, and (3 use of Hawley removable retainers with similar wearing instructions. Results: Independent and paired t-test statistical testing revealed the following: (1 Posttreatment orthodontic outcomes were the same, with or without corticotomy. (2 During retention, 5 of 8 ABO grading criteria improved for the sample without corticotomy, and 6 of 8 ABO grading criteria improved for the group with corticotomy. (3 Retention outcome scores were lower (better for alignment and marginal ridges in the corticotomy-facilitated group. (4 The total score was significantly lower (better for the corticotomy group at retention and the increment of total score change decreased (improved significantly more during retention following corticotomy. Conclusions: The retention phase was more favorable following corticotomy because the amount of OGS total score change demonstrated a significantly improved retention outcome following PAOO therapy.

  7. Compensation packages: a strategic tool for employees’ performance and retention

    Directory of Open Access Journals (Sweden)

    Omotayo Adewale OSIBANJO

    2014-02-01

    Full Text Available The rate at which employees in private universities in Nigeria jump from one university to the other is becoming more disturbing and this could be as a result of compensation packages of different universities to attract competent employees. The aim of this study was to examine the effect of compensation packages on employees’ job performance and retention in a selected private University in Ogun State, South-West Nigeria. A model was developed and tested using one hundred and eleven valid questionnaires which were completed by academics and non-academic staff of the university. The collected data were carefully analyzed using simple percentage supported by structural equation modelling to test the hypotheses and relationships that may exist among the variables under consideration. The results showed strong relationship between compensation packages and employees’ performance and retention. The summary of the findings indicates that there is strong correlation between the tested dependent and independent variables (salary, bonus, incentives, allowances, and fringe benefits. However, management and decision makers should endeavour to review compensation packages at various levels in order to earn employees’ satisfaction and prevention of high labour turnover among the members of staff.

  8. The Impact of Gloss Types on Reading Comprehension, Vocabulary Gain and Vocabulary Retention: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Atefeh Elekaei

    2015-09-01

    Full Text Available The significance and impact of vocabulary learning in reading comprehension and L2 language learning are apparent to teachers, researchers and language learners. Moreover, glosses are found as one of the most effective strategies regarding vocabulary retention. Therefore, the present study attempted to investigate the effect of different types of glosses on reading comprehension, vocabulary gain and vocabulary retention. To this end, 140 Iranian EFL learners learning English were selected and were divided into four groups (footnote gloss group, interlinear gloss group, marginal gloss group, and glossary group. They were required to read a text and answer four reading comprehension questions. In addition, one immediate vocabulary post-test and one delayed vocabulary post-test were taken in order to investigate learners' vocabulary gain and vocabulary retention. In order to analyze the data, one one-way ANOVA and one MANOVA were run. The results of one-way ANOVA revealed that participants who received interlinear glosses significantly outperformed the other groups regarding comprehending the text. Moreover, the immediate vocabulary post-test was conducted immediately after reading test and the delayed post-test was administered after four weeks. The results of MANOVA indicated that the group which received interlinear glosses outperformed the other groups in both vocabulary gain and vocabulary retention. The present study has implications for teachers and learners. Teachers can find better methods to teach new reading passages as well as vocabulary items. Also, glosses help learners to have a better comprehension of difficult passages and they facilitate learning. Moreover, learners can enhance their vocabulary knowledge with the help of glosses.

  9. Data Retention and Anonymity Services

    Science.gov (United States)

    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.

  10. Actual drawing of histological images improves knowledge retention.

    Science.gov (United States)

    Balemans, Monique C M; Kooloos, Jan G M; Donders, A Rogier T; Van der Zee, Catharina E E M

    2016-01-01

    Medical students have to process a large amount of information during the first years of their study, which has to be retained over long periods of nonuse. Therefore, it would be beneficial when knowledge is gained in a way that promotes long-term retention. Paper-and-pencil drawings for the uptake of form-function relationships of basic tissues has been a teaching tool for a long time, but now seems to be redundant with virtual microscopy on computer-screens and printers everywhere. Several studies claimed that, apart from learning from pictures, actual drawing of images significantly improved knowledge retention. However, these studies applied only immediate post-tests. We investigated the effects of actual drawing of histological images, using randomized cross-over design and different retention periods. The first part of the study concerned esophageal and tracheal epithelium, with 384 medical and biomedical sciences students randomly assigned to either the drawing or the nondrawing group. For the second part of the study, concerning heart muscle cells, students from the previous drawing group were now assigned to the nondrawing group and vice versa. One, four, and six weeks after the experimental intervention, the students were given a free recall test and a questionnaire or drawing exercise, to determine the amount of knowledge retention. The data from this study showed that knowledge retention was significantly improved in the drawing groups compared with the nondrawing groups, even after four or six weeks. This suggests that actual drawing of histological images can be used as a tool to improve long-term knowledge retention. © 2015 American Association of Anatomists.

  11. Recruitment Combined with Retention Strategies Results in Institutional Effectiveness and Student Satisfaction.

    Science.gov (United States)

    Youngman, Curtis

    In Winter 1994, the Marketing Department at Salt Lake Community College (SLCC) in Utah implemented an educational marketing plan that incorporated a focus on customer service to improve institutional effectiveness and student satisfaction. The plan includes a retention and recruitment program to strengthen the college's relationship with current


  12. Emotional intelligence and clinical performance/retention of nursing students

    Science.gov (United States)

    Marvos, Chelsea; Hale, Frankie B.

    2015-01-01

    Objective: This exploratory, quantitative, descriptive study was undertaken to explore the relationship between clinical performance and anticipated retention in nursing students. Methods: After approval by the university's Human Subjects Committee, a sample of 104 nursing students were recruited for this study, which involved testing with a valid and reliable emotional intelligence (EI) instrument and a self-report survey of clinical competencies. Results: Statistical analysis revealed that although the group average for total EI score and the 6 score subsets were in the average range, approximately 30% of the individual total EI scores and 30% of two branch scores, identifying emotions correctly and understanding emotions, fell in the less than average range. This data, as well as the analysis of correlation with clinical self-report scores, suggest recommendations applicable to educators of clinical nursing students. Conclusions: Registered nurses make-up the largest segment of the ever-growing healthcare workforce. Yet, retention of new graduates has historically been a challenge for the profession. Given the projected employment growth in nursing, it is important to identify factors which correlate with high levels of performance and job retention among nurses. There is preliminary evidence that EI a nontraditional intelligence measure relates positively not only with retention of clinical staff nurses, but with overall clinical performance as well. PMID:27981096

  13. Water Retention Curves of Opalinus Clay

    International Nuclear Information System (INIS)

    Villar, M. V.; Romero, F. J.

    2012-01-01

    The water retention curve of Opalinus clay samples was determined under different conditions: total and matric suction, stress or no-stress conditions, wetting and drying paths. Through the fitting of these results to the van Genuchten expression the P parameter, related to the air entry value (AEV), was obtained. The AEV is the suction value above which air is able to enter the pores of the sample, and consequently, above which 2-phase flow can take place in the soil pore structure. The samples used in this research came from two different boreholes, BHT-1 and BHG-D1, but the behaviour of them did not depend on their location, what was probably due to the fact that both were drilled in the shay facies of the Opalinus clay. There was not a distinct difference between the results obtained under total or matric suctions. In the drying paths, both the water contents and the degrees of saturation tended to be higher when total suction was applied, however the reverse trend was observed for the water contents reached in wetting paths. As well, no clear difference was observed in the water retention curves obtained in odometers under matric and total suctions, what points to the osmotic component of suction in Opalinus clay not being significant. Overall, the water contents were lower and the degrees of saturation higher when suction was applied under vertical stress, what would indicate that the water retention capacity was lower under 8 MPa vertical stress than under free volume conditions. This vertical stress value is slightly higher than the maximum in situ stress. Also, the samples showed hysteresis according to the expected behaviour, i.e. the water contents for a given suction were higher during a drying path than during a wetting path. The P values obtained were between 6 and 34 MPa, and tended to be higher for the samples tested under stress, in drying paths and when total suction was used. The air entry value calculated from the mercury intrusion porosimetry

  14. Water Retention Curves of Opalinus Clay

    Energy Technology Data Exchange (ETDEWEB)

    Villar, M. V.; Romero, F. J.

    2012-11-01

    The water retention curve of Opalinus clay samples was determined under different conditions: total and matric suction, stress or no-stress conditions, wetting and drying paths. Through the fitting of these results to the van Genuchten expression the P parameter, related to the air entry value (AEV), was obtained. The AEV is the suction value above which air is able to enter the pores of the sample, and consequently, above which 2-phase flow can take place in the soil pore structure. The samples used in this research came from two different boreholes, BHT-1 and BHG-D1, but the behaviour of them did not depend on their location, what was probably due to the fact that both were drilled in the shay facies of the Opalinus clay. There was not a distinct difference between the results obtained under total or matric suctions. In the drying paths, both the water contents and the degrees of saturation tended to be higher when total suction was applied, however the reverse trend was observed for the water contents reached in wetting paths. As well, no clear difference was observed in the water retention curves obtained in odometers under matric and total suctions, what points to the osmotic component of suction in Opalinus clay not being significant. Overall, the water contents were lower and the degrees of saturation higher when suction was applied under vertical stress, what would indicate that the water retention capacity was lower under 8 MPa vertical stress than under free volume conditions. This vertical stress value is slightly higher than the maximum in situ stress. Also, the samples showed hysteresis according to the expected behaviour, i.e. the water contents for a given suction were higher during a drying path than during a wetting path. The P values obtained were between 6 and 34 MPa, and tended to be higher for the samples tested under stress, in drying paths and when total suction was used. The air entry value calculated from the mercury intrusion porosimetry

  15. A Study of Retention Trends of International Students at a Southwestern Public University

    Science.gov (United States)

    Wong Davis, Kristina Marie

    2012-01-01

    Literature on factors contributing to the retention of international students remained limited. The purpose of this study was to examine the factors related to retention of international undergraduate degree seeking students through conducting pairwise correlational analysis to test the relationship between retention and age, gender, country of


  16. Uncovering client retention antecedents in service organizations

    Directory of Open Access Journals (Sweden)

    Mari Jansen van Rensburg

    2014-01-01

    Full Text Available This paper develops a multi-dimensional model of retention to provide a more complete and integrated view of client retention and its determinants in service contexts. To uncover the antecedents of client retention, social and economic exchanges were reviewed under the fundamental ideas of the Social Exchange Theory. Findings from a survey of senior South African advertising executives suggest that client retention is the result of evaluative as well as relational factors that can influence client responses. Despite contractual obligations, advertisers are willing to pay the costs and make the sacrifices of switching should their expectations be unmet. An important contribution of this study is the use of multi-item scales to measure retention. The model developed provides valuable insight to agencies on client retention management and the optimal allocation of resources for maximum customer equity. This model may also be applied to other service organisations to provide insight to client retention.

  17. The human body retention time of environmental organically bound Tritium : preliminary analysis of results from a volunteer study

    International Nuclear Information System (INIS)

    Hunt, John; Bailey, Trevor; Reese, Allan

    2008-01-01

    Tritium in the UK environment causes low radiation doses to the public, but uncertainty exists in the dose coefficient for the organically-bound component of tritium (OBT). This can affect the assessment of effective doses to representative persons. Contributing to that uncertainty is poor knowledge of the body retention time of OBT and how this varies for different OBT compounds in food. This study was undertaken to measure the retention time of tritium by volunteers after eating sole from Cardiff Bay, which may contain OBT from discharges from the GE Healthcare Ltd. plant. Five volunteers provided samples of excreta over periods up to 150 days after intake. Preliminary analysis of the results suggests retention of total tritium with body half-times ranging from 4 to 11 days, with no evidence of a significant contribution due to retention with a longer half-time. This range covers the half-time of 10 days used by the ICRP for tritiated water. The short timescale could be due to rapid hydrolysis in body tissues of the particular form of OBT used in this study. Implications for the dose coefficient for OBT are that the use of the ICRP value of 4.2 10- 11 Sv Bq -1 may be cautious in this specific situation, and the value of 1.6 10 -11 Sv Bq-1 used by the ICRP for tritiated water might even be more appropriate. These observations on dose coefficients are separate from any implications of recent discussion on whether the tritium radiation weighting factor should be increased from 1 to 2. (author)

  18. Estimating retention in HIV care accounting for patient transfers: A national laboratory cohort study in South Africa.

    Science.gov (United States)

    Fox, Matthew P; Bor, Jacob; Brennan, Alana T; MacLeod, William B; Maskew, Mhairi; Stevens, Wendy S; Carmona, Sergio

    2018-06-01

    Systematic reviews have described high rates of attrition in patients with HIV receiving antiretroviral therapy (ART). However, migration and clinical transfer may lead to an overestimation of attrition (death and loss to follow-up). Using a newly linked national laboratory database in South Africa, we assessed national retention in South Africa's national HIV program. Patients receiving care in South Africa's national HIV program are monitored through regular CD4 count and viral load testing. South Africa's National Health Laboratory Service has maintained a database of all public-sector CD4 count and viral load results since 2004. We linked individual laboratory results to patients using probabilistic matching techniques, creating a national HIV cohort. Validation of our approach in comparison to a manually matched dataset showed 9.0% undermatching and 9.5% overmatching. We analyzed data on patients initiating ART in the public sector from April 1, 2004, to December 31, 2006, when ART initiation could be determined based on first viral load among those whose treatment followed guidelines. Attrition occurred on the date of a patient's last observed laboratory measure, allowing patients to exit and reenter care prior to that date. All patients had 6 potential years of follow-up, with an additional 2 years to have a final laboratory measurement to be retained at 6 years. Data were censored at December 31, 2012. We assessed (a) national retention including all laboratory tests regardless of testing facility and (b) initiating facility retention, where laboratory tests at other facilities were ignored. We followed 55,836 patients initiating ART between 2004 and 2006. At ART initiation, median age was 36 years (IQR: 30-43), median CD4 count was 150 cells/mm3 (IQR: 81-230), and 66.7% were female. Six-year initiating clinic retention was 29.1% (95% CI: 28.7%-29.5%). After allowing for transfers, national 6-year retention was 63.3% (95% CI: 62.9%-63.7%). Results differed

  19. Mandibular Overdentures Retained by Two Mini-Implants: A Seven-Year Retention and Satisfaction Study.

    Science.gov (United States)

    CatalĂĄn, Alfonso; MartĂ­nez, Alejandra; Marchesani, Francisco; GonzĂĄlez, Urcesino

    2016-07-01

    Patients with atrophic edentulous ridges generally have problems with retention, therapeutic satisfaction, and comfort with their complete dentures. An alternative treatment to assist in improving retention and stability involves the use of mini-implants. The aim of this study was to evaluate the retention of mandibular overdentures connected to two mini-implants and overall patient satisfaction with them. Seven patients with atrophic mandibular ridges (Type 4D Misch classification), aged 62 to 74 years old were rehabilitated with complete dentures. In each patient, two mini-implants measuring 15 or 13 mm in length and 1.8 mm in diameter were placed. After 15 days, overdentures were connected to the mini-implants with O-ring attachments. In each patient, retention of the overdentures was measured, and a survey of therapeutic satisfaction before and after connection to the mini-implants was administered. Prosthesis retention was measured with a digital dynamometer at 1 month, 6 months, and 2, 3, 5, and 7 years after mini-implant placement. Patient satisfaction was assessed with a survey. Data were analyzed with Student's t-test (satisfaction survey) and the Friedman test (retention measurements and satisfaction survey). The initial retention values (0.34 to 0.63 N without mini-implants) varied significantly (p ≀ 0.050). These values were less than the subsequent measurements of 3.92 to 9.64 N, taken after placement of the mini-implants and connecting them to the dentures. Satisfaction was good to very good over the 7-year observation period. Mucosa and peri-implant bone showed no pathological changes. In this limited sample size clinical study the results indicated that after connecting mandibular overdentures to two mini-implants, patient satisfaction significantly increased and retention significantly improved during the 7-year observation period. © 2015 by the American College of Prosthodontists.

  20. Genetic programming based quantitative structure-retention relationships for the prediction of Kovats retention indices.

    Science.gov (United States)

    Goel, Purva; Bapat, Sanket; Vyas, Renu; Tambe, Amruta; Tambe, Sanjeev S

    2015-11-13

    The development of quantitative structure-retention relationships (QSRR) aims at constructing an appropriate linear/nonlinear model for the prediction of the retention behavior (such as Kovats retention index) of a solute on a chromatographic column. Commonly, multi-linear regression and artificial neural networks are used in the QSRR development in the gas chromatography (GC). In this study, an artificial intelligence based data-driven modeling formalism, namely genetic programming (GP), has been introduced for the development of quantitative structure based models predicting Kovats retention indices (KRI). The novelty of the GP formalism is that given an example dataset, it searches and optimizes both the form (structure) and the parameters of an appropriate linear/nonlinear data-fitting model. Thus, it is not necessary to pre-specify the form of the data-fitting model in the GP-based modeling. These models are also less complex, simple to understand, and easy to deploy. The effectiveness of GP in constructing QSRRs has been demonstrated by developing models predicting KRIs of light hydrocarbons (case study-I) and adamantane derivatives (case study-II). In each case study, two-, three- and four-descriptor models have been developed using the KRI data available in the literature. The results of these studies clearly indicate that the GP-based models possess an excellent KRI prediction accuracy and generalization capability. Specifically, the best performing four-descriptor models in both the case studies have yielded high (>0.9) values of the coefficient of determination (R(2)) and low values of root mean squared error (RMSE) and mean absolute percent error (MAPE) for training, test and validation set data. The characteristic feature of this study is that it introduces a practical and an effective GP-based method for developing QSRRs in gas chromatography that can be gainfully utilized for developing other types of data-driven models in chromatography science

  1. The Use of Computer-Based Videogames in Knowledge Acquisition and Retention.

    Science.gov (United States)

    Ricci, Katrina E.

    1994-01-01

    Research conducted at the Naval Training Systems Center in Orlando, Florida, investigated the acquisition and retention of basic knowledge with subject matter presented in the forms of text, test, and game. Results are discussed in terms of the effectiveness of computer-based games for military training. (Author/AEF)

  2. Load-Bearing Capacity and Retention of Newly Developed Micro-Locking Implant Prosthetic System: An In Vitro Pilot Study

    Directory of Open Access Journals (Sweden)

    Jae-Won Choi

    2018-04-01

    Full Text Available The aim of this study was to introduce the newly developed micro-locking implant prosthetic system and to evaluate the resulting its characteristics. To evaluate load-bearing capacity, 25 implants were divided into five groups: external-hexagon connection (EH, internal-octagon connection (IO, internal-hexagon connection (IH, one-body implant (OB, micro-locking implant system (ML. The maximum compressive load was measured using a universal testing machine (UTM according to the ISO 14801. Retention was evaluated in two experiments: (1 a tensile test of the structure modifications of the components (attachment and implant and (2 a tensile test after cyclic loading (total 5,000,000 cycles, 100 N, 2 Hz. The load-bearing capacity of the ML group was not significantly different from the other groups (p > 0.05. The number of balls in the attachment and the presence of a hexagonal receptacle did not show a significant correlation with retention (p > 0.05, but the shape of the retentive groove in the implant post had a statistically significant effect on retention (p < 0.05. On the other hand, the retention loss was observed during the initial 1,000,000 cycles, but an overall constant retention was maintained afterward. Various preclinical studies on this novel micro-locking implant prosthetic system should continue so that it can be applied in clinical practice.

  3. Evaluation of Data Retention Characteristics for Ferroelectric Random Access Memories (FRAMs)

    Science.gov (United States)

    Sharma, Ashok K.; Teverovsky, Alexander

    2001-01-01

    Data retention and fatigue characteristics of 64 Kb lead zirconate titanate (PZT)-based Ferroelectric Random Access Memories (FRAMs) microcircuits manufactured by Ramtron were examined over temperature range from -85 C to +310 C for ceramic packaged parts and from -85 C to +175 C for plastic parts, during retention periods up to several thousand hours. Intrinsic failures, which were caused by a thermal degradation of the ferroelectric cells, occurred in ceramic parts after tens or hundreds hours of aging at temperatures above 200 C. The activation energy of the retention test failures was 1.05 eV and the extrapolated mean-time-to-failure (MTTF) at room temperature was estimated to be more than 280 years. Multiple write-read cycling (up to 3x10(exp 7)) during the fatigue testing of plastic and ceramic parts did not result in any parametric or functional failures. However, operational currents linearly decreased with the logarithm of number of cycles thus indicating fatigue process in PZT films. Plastic parts, that had more recent date code as compared to ceramic parts, appeared to be using die with improved process technology and showed significantly smaller changes in operational currents and data access times.

  4. Promoting Special Educator Teacher Retention

    OpenAIRE

    Jeremy E. Vittek

    2015-01-01

    This article is a critical review of the literature on special education teacher attrition and retention. The research focused on journal articles from 2004 to present. The results of the study helped define special educator attrition and retention. The major themes present in the findings were job satisfaction, administrative support, induction programs, and mentoring. The literature shows a clear need for comprehensi...

  5. Vitamin B12 deficiency results in severe oxidative stress, leading to memory retention impairment in Caenorhabditis elegans.

    Science.gov (United States)

    Bito, Tomohiro; Misaki, Taihei; Yabuta, Yukinori; Ishikawa, Takahiro; Kawano, Tsuyoshi; Watanabe, Fumio

    2017-04-01

    Oxidative stress is implicated in various human diseases and conditions, such as a neurodegeneration, which is the major symptom of vitamin B 12 deficiency, although the underlying disease mechanisms associated with vitamin B 12 deficiency are poorly understood. Vitamin B 12 deficiency was found to significantly increase cellular H 2 O 2 and NO content in Caenorhabditis elegans and significantly decrease low molecular antioxidant [reduced glutathione (GSH) and L-ascorbic acid] levels and antioxidant enzyme (superoxide dismutase and catalase) activities, indicating that vitamin B 12 deficiency induces severe oxidative stress leading to oxidative damage of various cellular components in worms. An NaCl chemotaxis associative learning assay indicated that vitamin B 12 deficiency did not affect learning ability but impaired memory retention ability, which decreased to approximately 58% of the control value. When worms were treated with 1mmol/L GSH, L-ascorbic acid, or vitamin E for three generations during vitamin B 12 deficiency, cellular malondialdehyde content as an index of oxidative stress decreased to the control level, but the impairment of memory retention ability was not completely reversed (up to approximately 50%). These results suggest that memory retention impairment formed during vitamin B 12 deficiency is partially attributable to oxidative stress. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

  6. Employee Retention Strategies And Organizational Performance ...

    African Journals Online (AJOL)

    Implication of the results for practice is that any organization that fails to put in place adequate employee retention strategies is not likely to retain competent and motivated workforce in its employment and hence experience frequent labour turnover and poor organizational performance. Keywords: Employees, Retention ...

  7. Irrigation and Debridement with Component Retention for Acute Infection After Hip Arthroplasty: Improved Results with Contemporary Management.

    Science.gov (United States)

    Bryan, Andrew J; Abdel, Matthew P; Sanders, Thomas L; Fitzgerald, Steven F; Hanssen, Arlen D; Berry, Daniel J

    2017-12-06

    There are conflicting data on the results of irrigation and debridement with component retention in patients with acute periprosthetic hip infections. The goals of this study were to examine contemporary results of irrigation and debridement with component retention for acute infection after primary hip arthroplasty and to identify host, organism, antibiotic, or implant factors that predict success or failure. Ninety hips (57 total hip arthroplasties and 33 hemiarthroplasties) were diagnosed with acute periprosthetic hip infection (using strict criteria) and were treated with irrigation and debridement and component retention between 2000 and 2012. The mean follow-up was 6 years. Patients were stratified on the basis of McPherson criteria. Hips were managed with irrigation and debridement and retention of well-fixed implants with modular head and liner exchange (70%) or irrigation and debridement alone (30%). Seventy-seven percent of patients were treated with chronic antibiotic suppression. Failure was defined as failure to eradicate infection, characterized by a wound fistula, drainage, intolerable pain, or infection recurrence caused by the same organism strain; subsequent removal of any component for infection; unplanned second wound debridement for ongoing deep infection; and/or occurrence of periprosthetic joint infection-related mortality. Treatment failure occurred in 17% (15 of 90 hips), with component removal secondary to recurrent infection in 10% (9 of 90 hips). Treatment failure occurred in 15% (10 of 66 hips) after early postoperative infection and 21% (5 of 24 hips) after acute hematogenous infection (p = 0.7). Patients with McPherson host grade A had a treatment failure rate of 8%, compared with 16% (p = 0.04) in host grade B and 44% in host grade C (p = 0.006). Most treatment failures (12 of 15 failures) occurred within the initial 6 weeks of treatment; failures subsequent to 6 weeks occurred in 3% of those treated with chronic antibiotic

  8. 40 CFR 80.1348 - What gasoline sample retention requirements apply to refiners and importers?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false What gasoline sample retention... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Benzene Sampling, Testing and Retention Requirements § 80.1348 What gasoline sample retention requirements...

  9. Intact Acquisition and Short-Term Retention of Non-Motor Procedural Learning in Parkinson's Disease.

    Directory of Open Access Journals (Sweden)

    Muriel T N PanouillĂšres

    Full Text Available Procedural learning is a form of memory where people implicitly acquire a skill through repeated practice. People with Parkinson's disease (PD have been found to acquire motor adaptation, a form of motor procedural learning, similarly to healthy older adults but they have deficits in long-term retention. A similar pattern of normal learning on initial exposure with a deficit in retention seen on subsequent days has also been seen in mirror-reading, a form of non-motor procedural learning. It is a well-studied fact that disrupting sleep will impair the consolidation of procedural memories. Given the prevalence of sleep disturbances in PD, the lack of retention on following days seen in these studies could simply be a side effect of this well-known symptom of PD. Because of this, we wondered whether people with PD would present with deficits in the short-term retention of a non-motor procedural learning task, when the test of retention was done the same day as the initial exposure. The aim of the present study was then to investigate acquisition and retention in the immediate short term of cognitive procedural learning using the mirror-reading task in people with PD. This task involved two conditions: one where triads of mirror-inverted words were always new that allowed assessing the learning of mirror-reading skill and another one where some of the triads were presented repeatedly during the experiment that allowed assessing the word-specific learning. People with PD both ON and OFF their normal medication were compared to healthy older adults and young adults. Participants were re-tested 50 minutes break after initial exposure to probe for short-term retention. The results of this study show that all groups of participants acquired and retained the two skills (mirror-reading and word-specific similarly. These results suggest that neither healthy ageing nor the degeneration within the basal ganglia that occurs in PD does affect the mechanisms

  10. Wind Effects on Retention Time in Highway Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

    2007-01-01

    is to evaluate the quality of long term simulations based on historical rain series of the pollutant discharges from roads and highways. The idea of this paper is to evaluate the effects of wind on the retention time and compare the retention time for the situation of a spatial uniform wind shear stress...... with the situation of a "real" spatial non-uniform shear stress distribution on the surface of the pond. The result of this paper shows that wind plays a dominant role for the retention time and flow pattern. Furthermore, the results shows that the differences in retention time between the use of uniform and non...

  11. Wind Effects on Retention Time in Highway Ponds

    DEFF Research Database (Denmark)

    Bentzen, Thomas Ruby; Larsen, Torben; Rasmussen, Michael R.

    2008-01-01

    is to evaluate the quality of long term simulations based on historical rain series of the pollutant discharges from roads and highways. The idea of this paper is to evaluate the effects of wind on the retention time and compare the retention time for the situation of a spatial uniform wind shear stress...... with the situation of a "real" spatial non-uniform shear stress distribution on the surface of the pond. The result of this paper shows that wind plays a dominant role for the retention time and flow pattern. Furthermore, the results shows that the differences in retention time between the use of uniform and non...

  12. Retention Strength after Compressive Cyclic Loading of Five Luting Agents Used in Implant-Supported Prostheses

    Directory of Open Access Journals (Sweden)

    Angel Alvarez-Arenal

    2016-01-01

    Full Text Available The purpose of this study was to evaluate and compare the retention strength of five cement types commonly used in implant-retained fixed partial dentures, before and after compressive cyclic loading. In five solid abutments screwed to 5 implant analogs, 50 metal Cr-Ni alloy copings were cemented with five luting agents: resin-modified glass ionomer (RmGI, resin composite (RC, glass ionomer (GI, resin urethane-based (RUB, and compomer cement (CC. Two tensile tests were conducted with a universal testing machine, one after the first luting of the copings and the other after 100,000 cycles of 100 N loading at 0.72 Hz. The one way ANOVA test was applied for the statistical analysis using the post hoc Tukey test when required. Before and after applying the compressive load, RmGI and RC cement types showed the greatest retention strength. After compressive loading, RUB cement showed the highest percentage loss of retention (64.45%. GI cement recorded the lowest retention strength (50.35 N and the resin composite cement recorded the highest (352.02 N. The type of cement influences the retention loss. The clinician should give preference to lower retention strength cement (RUB, CC, and GI if he envisages any complications and a high retention strength one (RmGI, RC for a specific clinical situation.

  13. Home healthcare nurse retention and patient outcome model: discussion and model development.

    Science.gov (United States)

    Ellenbecker, Carol Hall; Cushman, Margaret

    2012-08-01

    This paper discusses additions to an empirically tested model of home healthcare nurse retention. An argument is made that the variables of shared decision-making and organizational commitment be added to the model based on the authors' previous research and additional evidence from the literature. Previous research testing the home healthcare nurse retention model established empirical relationships between nurse, agency, and area characteristics to nurse job satisfaction, intent to stay, and retention. Unexplained model variance prompted a new literature search to augment understanding of nurse retention and patient and agency outcomes. Data come from the authors' previous research, and a literature search from 1990 to 2011 on the topics organizational commitment, shared decision-making, nurse retention, patient outcomes and agency performance. The literature provides a rationale for the additional variables of shared decision-making and affective and continuous organizational commitment, linking these variables to nurse job satisfaction, nurse intent to stay, nurse retention and patient outcomes and agency performance. Implications for nursing.  The new variables in the model suggest that all agencies, even those not struggling to retain nurses, should develop interventions to enhance nurse job satisfaction to assure quality patient outcomes. The new nurse retention and patient outcome model increases our understanding of nurse retention. An understanding of the relationship among these variables will guide future research and the development of interventions to create and maintain nursing work environments that contribute to nurse affective agency commitment, nurse retention and quality of patient outcomes. © 2011 Blackwell Publishing Ltd.

  14. The effect of teaching method on long-term knowledge retention.

    Science.gov (United States)

    Beers, Geri W; Bowden, Susan

    2005-11-01

    Choosing a teaching strategy that results in knowledge retention on the part of learners can be challenging for educators. Studies on problem-based learning (PBL) have supported its effectiveness, compared to other, more traditional strategies. The results of a previous study comparing the effect of lecture versus PBL on objective test scores indicated there was no significant difference in scores. To measure long-term knowledge retention, the same groups were evaluated 1 year after instruction. The posttest administered in the original study was repeated, and the scores from a comprehensive adult health examination and the endocrine subsection were analyzed. At an alpha level of 0.05, a statistically significant difference was found in the scores on two of the measures. The scores of the PBL group were significantly higher on the endocrine section of the examination and the repeat posttest.

  15. Emotional intelligence and clinical performance/retention of nursing students

    Directory of Open Access Journals (Sweden)

    Chelsea Marvos

    2015-01-01

    Full Text Available Objective: This exploratory, quantitative, descriptive study was undertaken to explore the relationship between clinical performance and anticipated retention in nursing students. Methods: After approval by the universityâ€Čs Human Subjects Committee, a sample of 104 nursing students were recruited for this study, which involved testing with a valid and reliable emotional intelligence (EI instrument and a self-report survey of clinical competencies. Results: Statistical analysis revealed that although the group average for total EI score and the 6 score subsets were in the average range, approximately 30% of the individual total EI scores and 30% of two branch scores, identifying emotions correctly and understanding emotions, fell in the less than average range. This data, as well as the analysis of correlation with clinical self-report scores, suggest recommendations applicable to educators of clinical nursing students. Conclusions: Registered nurses make-up the largest segment of the ever-growing healthcare workforce. Yet, retention of new graduates has historically been a challenge for the profession. Given the projected employment growth in nursing, it is important to identify factors which correlate with high levels of performance and job retention among nurses. There is preliminary evidence that EI "a nontraditional intelligence measure" relates positively not only with retention of clinical staff nurses, but with overall clinical performance as well.

  16. Very long-term retention of basic science knowledge in doctors after graduation.

    Science.gov (United States)

    Custers, EugĂšne J F M; Ten Cate, Olle T J

    2011-04-01

    Despite frequent complaints that biomedical knowledge is quickly forgotten after it has been learned, few investigations of actual long-term retention of basic science knowledge have been conducted in the medical domain. Our aim was to illuminate the long-term retention of basic science knowledge, particularly of unrehearsed knowledge. Using a cross-sectional study design, medical students and doctors in the Netherlands were tested for retention of basic science knowledge. Relationships between retention interval and proportion of correct answers on a knowledge test were investigated. The popular notion that most of basic science knowledge is forgotten shortly after graduation is not supported by our findings. With respect to the full test scores, which reflect a composite of unrehearsed and rehearsed knowledge, performance decreased from approximately 40% correct answers for students still in medical school, to 25-30% correct answers for doctors after many years of practice. When rehearsal during the retention interval is controlled for, it appears that little knowledge is lost for 1.5-2 years after it was last used; from then on, retention is best described by a negatively accelerated (logarithmic) forgetting curve. After ≄ 25 years, retention levels were in the range of 15-20%. Conclusions about the forgetting of unrehearsed knowledge in this study are in line with findings reported in other domains: it proceeds in accordance with the Ebbinghaus curve for meaningful material, except that in our findings the 'downward' part appears to start later than in most other studies. The limitations of the study are discussed and possible ramifications for medical education are proposed. © Blackwell Publishing Ltd 2011.

  17. Retention of first aid and basic life support skills in undergraduate medical students

    Directory of Open Access Journals (Sweden)

    Pim A. de Ruijter

    2014-11-01

    Full Text Available Background: Undergraduate medical students follow a compulsory first aid (FA and basic life support (BLS course. Retention of BLS seems poor and only little information is provided on the retention of FA skills. This study aims at evaluating 1- and 2-year retention of FA and BLS training in undergraduate medical students. Methods: One hundred and twenty students were randomly selected from first year (n=349 medical students who successfully followed a compulsory FA and BLS course. From these 120 students, 94 (78% and 69 (58% participated in retention tests of FA and BLS skills after 1 and 2 years, respectively. The assessment consisted of two FA stations and one BLS station. Results: After 1 year, only 2% passed both FA and BLS stations and 68% failed both FA and BLS stations. After 2 years, 5% passed and 50% failed both FA and BLS stations. Despite the high failure rate at the stations, 90% adequately checked vital signs and started cardiopulmonary resuscitation appropriately. Conclusions: The long-term retention of FA and BLS skills after a compulsory course in the first year is poor. Adequate check of vital signs and commencing cardiopulmonary resuscitation retained longer.

  18. HIV testing uptake and retention in care of HIV-infected pregnant and breastfeeding women initiated on 'Option B+' in rural Zimbabwe.

    Science.gov (United States)

    Dzangare, Janet; Takarinda, Kudakwashe C; Harries, Anthony D; Tayler-Smith, Katie; Mhangara, Mutsa; Apollo, Tsitsi Mutasa; Mushavi, Angela; Chimwaza, Anesu; Sithole, Ngwarai; Magure, Tapiwa; Mpofu, Amon; Dube, Freeman; Mugurungi, Owen

    2016-02-01

    Zimbabwe has started to scale up Option B+ for the prevention of mother-to-child transmission of HIV, but there is little published information about uptake or retention in care. This study determined the number and proportion of pregnant and lactating women in rural districts diagnosed with HIV infection and started on Option B+ along with six-month antiretroviral treatment (ART) outcomes. This was a retrospective record review of women presenting to antenatal care or maternal and child health services at 34 health facilities in Chikomba and Gutu rural districts, Zimbabwe, between January and March 2014. A total of 2728 women presented to care of whom 2598 were eligible for HIV testing: 76% presented to antenatal care, 20% during labour and delivery and 4% while breastfeeding. Of 2097 (81%) HIV-tested women, 7% were HIV positive. Lower HIV testing uptake was found with increasing parity, late presentation to antenatal care, health centre attendance and in women tested during labour. Ninety-one per cent of the HIV-positive women were started on Option B+. Six-month ART retention in care, including transfers, was 83%. Loss to follow-up was the main cause of attrition. Increasing age and gravida status ≄2 were associated with higher six-month attrition. The uptake of HIV testing and Option B+ is high in women attending antenatal and post-natal clinics in rural Zimbabwe, suggesting that the strategy is feasible for national scale-up in the country. © 2015 John Wiley & Sons Ltd.

  19. Electroacupuncture versus sham electroacupuncture for urinary retention in poststroke patients: study protocol for a multicenter, randomized controlled trial.

    Science.gov (United States)

    Shin, Seungwon; Lee, Jiwon; Yoo, Junghee; Lim, Sung Min; Lee, Euiju

    2016-04-12

    This study protocol evaluates the effectiveness of adjuvant electroacupuncture (EA) for urinary retention in poststroke patients undergoing conventional treatments, in comparison with that of a sham control. A multicenter, blinded, randomized controlled trial will be conducted in three hospitals in the Republic of Korea. We are recruiting 54 stroke survivors (aged >19 years), who were diagnosed with urinary retention based on the results of two consecutive post-void residual (PVR) tests, and dividing them randomly into two arms: the EA and Park-sham control groups. They will receive ten sessions of EA or sham treatment for 2 weeks. The participants will be blinded with non-penetrating needles and fake sounds of EA stimulators. The daily PVR ratio will be primarily measured at baseline and at the end of the study to statistically test the effectiveness of EA for poststroke urinary retention. Then, the Korean version of the Qualiveen Questionnaire, the Korean version of the International Prostate Symptom Score, and the blinding index will be assessed. After each EA session or sham EA, adverse events will be reported to evaluate the safety of EA. Results will be analyzed by using the independent t-test or Mann-Whitney U test, based on both intention-to-treat and per-protocol principles. The findings will provide clinical evidence for the effectiveness of EA treatment to improve urinary retention in stroke survivors. This study protocol was registered in ClinicalTrials.gov (NCT02472288) on 10 June 2015.

  20. In situ vitrification: Preliminary results from the first large-scale radioactive test

    International Nuclear Information System (INIS)

    Buelt, J.L.; Westsik, J.H.

    1988-02-01

    The first large-scale radioactive test (LSRT) of In Situ Vitrification (ISV) has been completed. In Situ Vitrification is a process whereby joule heating immobilizes contaminated soil in place by converting it to a durable glass and crystalline waste form. The LSRT was conducted at an actual transuranic contaminated soil site on the Department of Energy's Hanford Site. The test had two objectives: (1) determine large-scale processing performance and (2) produce a waste form that can be fully evaluated as a potential technique for the final disposal of transuranic-contaminated soil sites at Hanford. This accomplishment has provided technical data to evaluate the ISV process for its potential in the final disposition of transuranic-contaminated soil sites at Hanford. Because of the test's successful completion, within a year technical data on the vitrified soil will be available to determine how well the process incorporates transuranics into the waste form and how well the form resists leaching of transuranics. Preliminary results available include retention of transuranics and other elements within the waste form during processing and the efficiency of the off-gas treatment system in removing contaminants from the gaseous effluents. 13 refs., 10 figs., 5 tabs

  1. Effect of Abutment Modification and Cement Type on Retention of Cement-Retained Implant Supported Crowns

    Science.gov (United States)

    Farzin, Mitra; Torabi, Kianoosh; Ahangari, Ahmad Hasan; Derafshi, Reza

    2014-01-01

    Objective: Provisional cements are commonly used to facilitate retrievability of cement-retained fixed implant restorations; but compromised abutment preparation may affect the retention of implant-retained crowns.The purpose of this study was to investigate the effect of abutment design and type of luting agent on the retentive strength of cement-retained implant restorations. Materials and Method: Two prefabricated abutments were attached to their corresponding analogs and embedded in an acrylic resin block. The first abutment (control group) was left intact without any modifications. The screw access channel for the first abutment was completely filled with composite resin. In the second abutment, (test group) the axial wall was partially removed to form an abutment with 3 walls. Wax models were made by CAD/CAM. Ten cast copings were fabricated for each abutment. The prepared copings were cemented on the abutments by Temp Bond luting agent under standardized conditions (n=20). The assemblies were stored in 100% humidity for one day at 37°C prior to testing. The cast crown was removed from the abutment using an Instron machine, and the peak removal force was recorded. Coping/abutment specimens were cleaned after testing, and the testing procedure was repeated for Dycal luting agent (n=20). Data were analyzed with two- way ANOVA (α=0.05). Results: There was no significant difference in the mean transformed retention (Ln-R) between intact abutments (4.90±0.37) and the abutments with 3 walls (4.83±0.25) using Dycal luting agent. However, in TempBond group, the mean transformed retention (Ln-R) was significantly lower in the intact abutment (3.9±0.23) compared to the abutment with 3 walls (4.13±0.33, P=0.027). Conclusion: The retention of cement-retained implant restoration can be improved by the type of temporary cement used. The retention of cast crowns cemented to implant abutments with TempBond is influenced by the wall removal. PMID:25628660

  2. Multiple coding strategies in the retention of musical tones by possessors of absolute pitch.

    Science.gov (United States)

    Zatorre, R J; Beckett, C

    1989-09-01

    Eighteen musicians with absolute pitch (AP) confirmed by screening tests participated in tonal and verbal short-term-retention tasks. In the tonal task, subjects identified three successive piano tones by their letter names. Recall of these note names after 18 sec of counting backwards was near perfect. Recall after an 18-sec delay filled with random piano tones was also near perfect. In contrast, the same subjects demonstrated significant forgetting when required to retain letter trigrams while counting backwards for 18 sec. These results were essentially replicated in a second experiment using longer (27 sec) retention intervals, a more demanding verbal interference task, and an active musical interference task (singing a descending scale). We interpret these results as indicating that retention of note names by possessors of AP is not limited to verbal encoding; rather, multiple codes (e.g., auditory, kinesthetic, and visual imagery) are probably used.

  3. Water Retention Capacity of Argillite from the VE Test - Phase II at Mont Terri: Effect of Ventilation

    International Nuclear Information System (INIS)

    Villar, M. V.; Fernandez, A. M.; Melon, A. M.

    2009-01-01

    The VE (ventilation) test carried out at the Mont Terri underground laboratory in Switzerland intended to evaluate in situ the behaviour of a consolidated clay formation when subjected to alternate periods of flow of wet and dry air during several months. For that, a 10-m gallery was excavated in the Opalinus Clay formation and carefully instrumented. Before and after a second ventilation phase boreholes were drilled. Samples were taken from the drill cores and were analysed from mineralogical and geochemical points of view. Also, the retention curves of these samples were determined in the laboratory following drying paths performed under free volume conditions at 20 degree centigrade, what is the content of this report. Although there are not large differences in the WRC of samples taken from different boreholes, at different distances from the gallery wall or before or after ventilation, those samples taken near the gallery wall and after ventilation tend to show a higher water retention capacity. This has been correlated to the higher salinity of the pore water of these samples, what increases their osmotic suction. This effect is attenuated towards high suctions. (Author) 10 refs

  4. Water Retention Capacity of Argillite from the VE Test - Phase II at Mont Terri: Effect of Ventilation

    Energy Technology Data Exchange (ETDEWEB)

    Villar, M. V.; Fernandez, A. M.; Melon, A. M.

    2009-10-12

    The VE (ventilation) test carried out at the Mont Terri underground laboratory in Switzerland intended to evaluate in situ the behaviour of a consolidated clay formation when subjected to alternate periods of flow of wet and dry air during several months. For that, a 10-m gallery was excavated in the Opalinus Clay formation and carefully instrumented. Before and after a second ventilation phase boreholes were drilled. Samples were taken from the drill cores and were analysed from mineralogical and geochemical points of view. Also, the retention curves of these samples were determined in the laboratory following drying paths performed under free volume conditions at 20 degree centigrade, what is the content of this report. Although there are not large differences in the WRC of samples taken from different boreholes, at different distances from the gallery wall or before or after ventilation, those samples taken near the gallery wall and after ventilation tend to show a higher water retention capacity. This has been correlated to the higher salinity of the pore water of these samples, what increases their osmotic suction. This effect is attenuated towards high suctions. (Author) 10 refs.

  5. Flocculation of retention pond water

    International Nuclear Information System (INIS)

    Hart, B.T.; McGregor, R.J.

    1982-05-01

    An integral part of the water management strategy proposed by Ranger Uranium Mining Pty. Ltd. involves the collection of runoff water in a series of retention ponds. This water will subsequently be used in the uranium milling plant or released to Magela Creek. Runoff water collected during the wet season caused a section of Magela Creek to become turbid when it was released. The eroded material causing the turbidity was very highly dispersed and showed little tendency to sediment out in the retention ponds. Results of a preliminary study to determine the feasibility of clarifying retention pond water by flocculation with alum are presented. A concentration of 30 Mg/L alum reduced turbidity from an initial 340 NTU to less than 30 NTU in four hours

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

    Science.gov (United States)

    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.

  7. An Experimental Study on the Impact of Different-frequency Elastic Waves on Water Retention Curve

    Science.gov (United States)

    Deng, J. H.; Dai, J. Y.; Lee, J. W.; Lo, W. C.

    2017-12-01

    ABSTEACTOver the past few decades, theoretical and experimental studies on the connection between elastic wave attributes and the physical properties of a fluid-bearing porous medium have attracted the attention of many scholars in fields of porous medium flow and hydrogeology. It has been previously determined that the transmission of elastic waves in a porous medium containing two immiscible fluids will have an effect on the water retention curve, but it has not been found that the water retention curve will be affected by the frequency of elastic vibration waves or whether the effect on the soil is temporary or permanent. This research is based on a sand box test in which the soil is divided into three layers (a lower, middle, and upper layer). In this case, we discuss different impacts on the water retention curve during the drying process under sound waves (elastic waves) subject to three frequencies (150Hz, 300Hz, and 450Hz), respectively. The change in the water retention curve before and after the effect is then discussed. In addition, how sound waves affect the water retention curve at different depths is also observed. According to the experimental results, we discover that sound waves can cause soil either to expand or to contract. When the soil is induced to expand due to sound waves, it can contract naturally and return to the condition it was in before the influence of the sound waves. On the contrary, when the soil is induced to contract, it is unable to return to its initial condition. Due to the results discussed above, it is suggested that sound waves causing soil to expand have a temporary impact while those causing soil to contract have a permanent impact. In addition, our experimental results show how sound waves affect the water retention curve at different depths. The degree of soil expansion and contraction caused by the sound waves will differ at various soil depths. Nevertheless, the expanding or contracting of soil is only subject to the

  8. Effect of preparation convergence on retention of multiple unit restorations - An in vitrostudy

    Directory of Open Access Journals (Sweden)

    Dileep Nag Vinnakota

    2015-01-01

    Full Text Available Background and Aim: Convergence angle (CA is one of the major determinant factors in the retention of single as well as multiple units. Hence, the aim of the present study was to determine the effect of preparation convergence on the retention of multiple unit restorations. Materials and Methods: Nickel-chromium alloy single crowns as well as three, six and nine multiple unit fixed partial dentures (FPDs were casted for standardized milled dies that simulate canine, premolar and molar teeth machined with two different degrees of convergence, 12 (n = 55 and 20 (n = 55. The dies were threaded on rectangular metal platforms with the help of retainer shaft in the proper position to model either single or multiple preparations. The casted crowns and FPDs were cemented and retention tested by securing the units in an Instron universal testing machine. The tabulated values were analyzed statistically using Mann-Whitney test. Results: Single and multiple units with 12° CA needed greater force to dislodge compared to 20°, but this difference was not statistically significant for single units of premolar (P > 0.05. Irrespective of the angle, there was a simultaneous statistically significant increase in retention as the number of units increased in FPDs, except for the difference between 3 and 6 units in 20° group (P > 0.05. Conclusion: This study highlights the importance of emphasizing on CA, during canine and molar preparation for single units as well as preparation of canines for 6 units FPDs.

  9. Modulation of NADPH oxidase activity by known uraemic retention solutes.

    Science.gov (United States)

    Schulz, Anna Marta; Terne, Cindy; Jankowski, Vera; Cohen, Gerald; Schaefer, Mandy; Boehringer, Falko; Tepel, Martin; Kunkel, Desiree; Zidek, Walter; Jankowski, Joachim

    2014-08-01

    Uraemia and cardiovascular disease appear to be associated with an increased oxidative burden. One of the key players in the genesis of reactive oxygen species (ROS) is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Based on initial experiments demonstrating a decreased inhibitory effect on NADPH oxidase activity in the presence of plasma from patients with CKD-5D after dialysis compared with before dialysis, we investigated the effect of 48 known and commercially available uraemic retention solutes on the enzymatic activity of NADPH oxidase. Mononuclear leucocytes isolated from buffy coats of healthy volunteers were isolated, lysed and incubated with NADH in the presence of plasma from healthy controls and patients with CKD-5D. Furthermore, the leucocytes were lysed and incubated in the presence of uraemic retention solute of interest and diphenyleneiodonium chloride (DPI), an inhibitor of NADPH oxidase. The effect on enzymatic activity of NADPH oxidase was quantified within an incubation time of 120 min. Thirty-nine of the 48 uraemic retention solutes tested had a significant decreasing effect on NADPH oxidase activity. Oxalate has been characterized as the strongest inhibitor of NADPH oxidase (90% of DPI inhibition). Surprisingly, none of the uraemic retention solutes we investigated was found to increase NADPH oxidase activity. Furthermore, plasma from patients with CKD-5D before dialysis caused significantly higher inhibitory effect on NADPH oxidase activity compared with plasma from healthy subjects. However, this effect was significantly decreased in plasma from patients with CKD-5D after dialysis. The results of this study show that uraemic retention solutes modulated the activity of the NADPH oxidase. The results of this study might be the basis for the development of inhibitors applicable as drug in the situation of increased oxidative stress. © 2014 Stichting European Society for Clinical Investigation Journal Foundation.

  10. Best practices in doctoral retention: Mentoring

    Directory of Open Access Journals (Sweden)

    Judie L. Brill

    2014-06-01

    Full Text Available  The aim of this critical literature review is to outline best practices in doctoral retention and the successful approach of one university to improve graduation success by providing effective mentorship for faculty and students alike. The focus of this literature review is on distance learning relationships between faculty and doctoral students, regarding retention, persistence, and mentoring models. Key phrases and words used in the search and focusing on mentoring resulted in over 20,000 sources. The search was narrowed to include only doctoral study and mentoring. Research questions of interest were: Why do high attrition rates exist for doctoral students? What are the barriers to retention? What are the benefits of doctoral mentoring? What programs do institutions have in place to reduce attrition? The researchers found a key factor influencing doctoral student retention and success is effective faculty mentorship. In particular, the design of a mentoring and faculty training program to increase retention and provide for success after graduation is important. This research represents a key area of interest in the retention literature, as institutions continue to search for ways to better support students during their doctoral programs and post-graduation. DOI: 10.18870/hlrc.v4i2.186

  11. Pre-training evaluation and feedback improved skills retention of basic life support in medical students.

    Science.gov (United States)

    Li, Qi; Zhou, Rong-hua; Liu, Jin; Lin, Jing; Ma, Er-Li; Liang, Peng; Shi, Ting-wei; Fang, Li-qun; Xiao, Hong

    2013-09-01

    Pre-training evaluation and feedback have been shown to improve medical students' skills acquisition of basic life support (BLS) immediately following training. The impact of such training on BLS skills retention is unknown. This study was conducted to investigate effects of pre-training evaluation and feedback on BLS skills retention in medical students. Three hundred and thirty 3rd year medical students were randomized to two groups, the control group (C group) and pre-training evaluation and feedback group (EF group). Each group was subdivided into four subgroups according to the time of retention-test (at 1-, 3-, 6-, 12-month following the initial training). After a 45-min BLS lecture, BLS skills were assessed (pre-training evaluation) in both groups before training. Following this, the C group received 45 min training. 15 min of group feedback corresponding to students' performance in pre-training evaluation was given only in the EF group that was followed by 30 min of BLS training. BLS skills were assessed immediately after training (post-test) and at follow up (retention-test). No skills difference was observed between the two groups in pre-training evaluation. Better skills acquisition was observed in the EF group (85.3 ± 7.3 vs. 68.1 ± 12.2 in C group) at post-test (p<0.001). In all retention-test, better skills retention was observed in each EF subgroup, compared with its paired C subgroup. Pre-training evaluation and feedback improved skills retention in the EF group for 12 months after the initial training, compared with the control group. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  12. Mate retention tactics in Spain: personality, sex differences, and relationship status.

    Science.gov (United States)

    de Miguel, Adelia; Buss, David M

    2011-06-01

    Mate retention is an important problem in romantic relationships because of mate poachers, infidelity, and the risk of outright defection. The current study (N=892) represents the first study of mate retention tactics conducted in Spain. We tested hypotheses about the effects of gender, relationship commitment status, and personality on mate retention tactics. Women and men differed in the use of resource display, appearance enhancement, intrasexual violence, and submission/self-abasement as mate retention tactics. Those in more committed relationships reported higher levels of resource display, appearance enhancement, love, and verbal signals of possession. Those in less committed relationships more often reported intentionally evoking jealousy in their partner as a mate retention tactic. Personality characteristics, particularly Neuroticism and Agreeableness, correlated in coherent ways with mate retention tactics, supporting two evolution-based hypotheses. Discussion focuses on the implications, future research directions, and interdisciplinary syntheses emerging between personality and social psychology and evolutionary psychology. © 2011 The Authors. Journal of Personality © 2011, Wiley Periodicals, Inc.

  13. Postgraduation retention of medical students from Otago and Auckland medical programmes.

    Science.gov (United States)

    Shelker, William; Poole, Phillippa; Bagg, Warwick; Wood, Ian; Glue, Paul

    2014-01-24

    Auckland and Otago medical programmes have different methods for selecting students. This study compared postgraduate retention in New Zealand (NZ) of medical graduates from the two medical programmes, to assess whether different selection methods influenced retention. Other variables assessed included entrance category and age at graduation. Anonymised databases were created of all graduates from the Otago Faculty of Medicine (1999-2011) and the Auckland medical programme (2000-2012). Demographic and entry category data were recorded. Retention was defined as presence on the NZ Medical Register in December 2012. Risk differences (RD) were calculated to compare retention between the two medical programmes using the Mantel-Haenszel method. The influence of medical programme entrance category on retention was also tested. The influence of covariates on retaining graduates on the register was evaluated using a multiple logistic regression model. The postgraduate retention of graduates of the two medical programmes over 13 years was identical (Auckland 74.9%, Otago 73.6%, P=0.48). Retention of graduate and non-graduate entry students from both medical programmes was similar by 6 years after graduation. Age during medical school did not affect retention. University of attendance had no effect on postgraduation retention of students on the NZ Medical Register, suggesting that retention is not influenced by the different student selection methods at each programme. The data presented shows that New Zealand graduates regardless of programme completed show a similar profile in terms of retention.

  14. Retention Strength of Conical Welding Caps for Fixed Implant-Supported Prostheses.

    Science.gov (United States)

    Nardi, Diego; Degidi, Marco; Sighinolfi, Gianluca; Tebbel, Florian; Marchetti, Claudio

    This study evaluated the retention strength of welding caps for Ankylos standard abutments using a pull-out test. Each sample consisted of an implant abutment and its welding cap. The tests were performed with a Zwick Roell testing machine with a 1-kN load cell. The retention strength of the welding caps increased with higher abutment diameters and higher head heights and was comparable or superior to the values reported in the literature for the temporary cements used in implant dentistry. Welding caps provide a reliable connection between an abutment and a fixed prosthesis without the use of cement.

  15. Progress Testing for Medical Students at the University of Auckland: Results from the First Year of Assessments

    Directory of Open Access Journals (Sweden)

    Steven Lillis

    2014-01-01

    Full Text Available Background Progress testing is a method of assessing longitudinal progress of students using a single best answer format pitched at the standard of a newly graduated doctor. Aim To evaluate the results of the first year of summative progress testing at the University of Auckland for Years 2 and 4 in 2013. SUBJECTS: Two cohorts of medical students from Years 2 and 4 of the Medical Program. Methods A survey was administered to all involved students. Open text feedback was also sought. Psychometric data were collected on test performance, and indices of reliability and validity were calculated. Results The three tests showed increased mean scores over time. Reliability of the assessments was uniformly high. There was good concurrent validity. Students believe that progress testing assists in integrating science with clinical knowledge and improve learning. Year 4 students reported improved knowledge retention and deeper understanding. Conclusion Progress testing has been successfully introduced into the Faculty for two separate year cohorts and results have met expectations. Other year cohorts will be added incrementally. Recommendation Key success factors for introducing progress testing are partnership with an experienced university, multiple and iterative briefings with staff and students as well as demonstrating the usefulness of progress testing by providing students with detailed feedback on performance.

  16. HPLC retention thermodynamics of grape and wine tannins.

    Science.gov (United States)

    Barak, Jennifer A; Kennedy, James A

    2013-05-08

    The effect of grape and wine tannin structure on retention thermodynamics under reversed-phase high-performance liquid chromatography conditions on a polystyrene divinylbenzene column was investigated. On the basis of retention response to temperature, an alternative retention factor was developed to approximate the combined temperature response of the complex, unresolvable tannin mixture. This alternative retention factor was based upon relative tannin peak areas separated by an abrupt change in solvent gradient. Using this alternative retention factor, retention thermodynamics were calculated. Van't Hoff relationships of the natural log of the alternative retention factor against temperature followed Kirchoff's relationship. An inverse quadratic equation was fit to the data, and from this the thermodynamic parameters for tannin retention were calculated. All tannin fractions exhibited exothermic, spontaneous interaction, with enthalpy-entropy compensation observed. Normalizing for tannin size, distinct tannin compositional effects on thermodynamic parameters were observed. The results of this study indicate that HPLC can be valuable for measuring the thermodynamics of tannin interaction with a hydrophobic surface and provides a potentially valuable alternative to calorimetry. Furthermore, the information gathered may provide insight into understanding red wine astringency quality.

  17. Social Media Interventions to Promote HIV Testing, Linkage, Adherence, and Retention: Systematic Review and Meta-Analysis.

    Science.gov (United States)

    Cao, Bolin; Gupta, Somya; Wang, Jiangtao; Hightow-Weidman, Lisa B; Muessig, Kathryn E; Tang, Weiming; Pan, Stephen; Pendse, Razia; Tucker, Joseph D

    2017-11-24

    Social media is increasingly used to deliver HIV interventions for key populations worldwide. However, little is known about the specific uses and effects of social media on human immunodeficiency virus (HIV) interventions. This systematic review examines the effectiveness of social media interventions to promote HIV testing, linkage, adherence, and retention among key populations. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist and Cochrane guidelines for this review and registered it on the International Prospective Register of Systematic Reviews, PROSPERO. We systematically searched six databases and three conference websites using search terms related to HIV, social media, and key populations. We included studies where (1) the intervention was created or implemented on social media platforms, (2) study population included men who have sex with men (MSM), transgender individuals, people who inject drugs (PWID), and/or sex workers, and (3) outcomes included promoting HIV testing, linkage, adherence, and/or retention. Meta-analyses were conducted by Review Manager, version 5.3. Pooled relative risk (RR) and 95% confidence intervals were calculated by random-effects models. Among 981 manuscripts identified, 26 studies met the inclusion criteria. We found 18 studies from high-income countries, 8 in middle-income countries, and 0 in low-income countries. Eight were randomized controlled trials, and 18 were observational studies. All studies (n=26) included MSM; five studies also included transgender individuals. The focus of 21 studies was HIV testing, four on HIV testing and linkage to care, and one on antiretroviral therapy adherence. Social media interventions were used to do the following: build online interactive communities to encourage HIV testing/adherence (10 studies), provide HIV testing services (9 studies), disseminate HIV information (9 studies), and develop intervention materials (1 study). Of the

  18. Retention of Content Utilizing a Flipped Classroom Approach.

    Science.gov (United States)

    Shatto, Bobbi; LÊŒEcuyer, Kristine; Quinn, Jerod

    The flipped classroom experience promotes retention and accountability for learning. The authors report their evaluation of a flipped classroom for accelerated second-degree nursing students during their primary medical-surgical nursing course. Standardized HESIÂź scores were compared between a group of students who experienced the flipped classroom and a previous group who had traditional teaching methods. Short- and long-term retention was measured using standardized exams 3 months and 12 months following the course. Results indicated that short-term retention was greater and long- term retention was significantly great in the students who were taught using flipped classroom methodology.

  19. Summary of aerosol code-comparison results for LWR aerosol containment tests LA1, LA2, and LA3

    International Nuclear Information System (INIS)

    Wright, A.L.; Wilson, J.H.; Arwood, P.C.

    1987-01-01

    The light-water reactor (LWR) aerosol containment experiments (LACE) are being performed in Richland, Washington, at the Hanford Engineering Development Laboratory under the leadership of an international project board and the Electric Power Research Institute. These tests have two objectives: (1) to investigate, at large scale, the inherent aerosol retention behavior in LWR containments under simulated severe accident conditions, and (2) to provide an experimental data base for validating aerosol behavior and thermal-hydraulic computer codes. Aerosol computer-code comparison activities for the LACE tests are being coordinated at the Oak Ridge National Laboratory. For each of the six experiments, pretest calculations (for code-to-code comparisons) and blind post-test calculations (for code-to-test data comparisons) are being performed. This paper presents a summary of the pretest aerosol-code results for tests LA1, LA2, and LA3

  20. Memory by association: Integrating memories prolongs retention by two-year-olds.

    Science.gov (United States)

    Hayne, Harlene; Gross, Julien

    2017-02-01

    Recalling one memory often leads to the recollection of other memories that share overlapping features. This phenomenon, spreading activation, was originally documented in studies conducted with verbal adults, and more recently, it has been demonstrated with preverbal infants. Here, we examine the effect of spreading activation on long-term retention by 2-year-olds. Participants were tested in the Visual Recognition Memory (VRM) paradigm and the deferred imitation paradigm. Typically, infants of this age exhibit retention in the VRM paradigm for 24h, while they exhibit retention in the deferred imitation paradigm for at least 8 weeks. In the present experiment, we paired these tasks together during original encoding and tested infants after an 8-week delay. Two-year-olds exhibited retention in both tasks. That is, when these two tasks initially occurred together - one task that is extremely memorable and one that is not - retrieving the memory of the more memorable task cued retrieval of the less memorable task, extending its longevity. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. Modulation of NADPH oxidase activity by known uraemic retention solutes

    DEFF Research Database (Denmark)

    Schulz, Anna Marta; Terne, Cindy; Jankowski, Vera

    2014-01-01

    chloride (DPI), an inhibitor of NADPH oxidase. The effect on enzymatic activity of NADPH oxidase was quantified within an incubation time of 120 min. RESULTS: Thirty-nine of the 48 uraemic retention solutes tested had a significant decreasing effect on NADPH oxidase activity. Oxalate has been characterized......BACKGROUND: Uraemia and cardiovascular disease appear to be associated with an increased oxidative burden. One of the key players in the genesis of reactive oxygen species (ROS) is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Based on initial experiments demonstrating a decreased...... inhibitory effect on NADPH oxidase activity in the presence of plasma from patients with CKD-5D after dialysis compared with before dialysis, we investigated the effect of 48 known and commercially available uraemic retention solutes on the enzymatic activity of NADPH oxidase. METHODS: Mononuclear leucocytes...

  2. Mobile Learning and Student Retention

    Directory of Open Access Journals (Sweden)

    Bharat Inder Fozdar

    2007-06-01

    Full Text Available 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 been well researched. The main aim of our research, therefore, is to better understand and measure students’ attitudes and perceptions towards the effectiveness of mobile learning. Our hope is to determine how this technology can be optimally used to improve student retention at Bachelor of Science programmes at Indira Gandhi National Open University (IGNOU in India. For our research, we used a survey. Results of this survey clearly indicate that offering mobile learning could be one method improving retention of BSc students, by enhancing their teaching/ learning and improving the efficacy of IGNOU’s existing student support system. The biggest advantage of this technology is that it can be used anywhere, anytime. Moreover, as mobile phone usage in India explodes, it offers IGNOU easy access to a larger number of learners. This study is intended to help inform those who are seeking to adopt mobile learning systems with the aim of improving communication and enriching students’ learning experiences in their ODL institutions.

  3. Neutral particle retention in the JET MK I divertor

    International Nuclear Information System (INIS)

    Ehrenberg, J.K.; Campbell, D.J.; Harbour, P.J.; Horton, L.D.; Loarte, A.; McCormick, G.K.; Monk, R.D.; Saibene, G.R.; Simonini, R.; Taroni, A.; Stamp, M.F.

    1997-01-01

    Retention of neutral deuterium and nitrogen in the JET MK I divertor has been investigated. Results show that ohmic plasma detachment reduces deuterium retention, that the magnetic divertor configuration has some influence on the achievable deuterium retention, and that nitrogen in nitrogen-seeded steady state detached H-mode discharges accumulates in the divertor. (orig.)

  4. Promoting Special Educator Teacher Retention

    Directory of Open Access Journals (Sweden)

    Jeremy E. Vittek

    2015-06-01

    Full Text Available This article is a critical review of the literature on special education teacher attrition and retention. The research focused on journal articles from 2004 to present. The results of the study helped define special educator attrition and retention. The major themes present in the findings were job satisfaction, administrative support, induction programs, and mentoring. The literature shows a clear need for comprehensive administrative support to improve job satisfaction and the likelihood a special educator will remain in their job.

  5. The Effect of Typographical Features of Subtitles on Nonnative English Viewers’ Retention and Recall of Lyrics in English Music Videos

    Directory of Open Access Journals (Sweden)

    Farshid Tayari Ashtiani

    2017-10-01

    Full Text Available The goal of this study was to test the effect of typographical features of subtitles including size, color and position on nonnative English viewers’ retention and recall of lyrics in music videos. To do so, the researcher played a simple subtitled music video for the participants at the beginning of their classes, and administered a 31-blank cloze test from the lyrics at the end of the classes. In the second test, the control group went through the same procedure but experimental group watched the customized subtitled version of the music video. The results demonstrated no significant difference between the two groups in the first test but in the second, the scores remarkably increased in the experimental group and proved better retention and recall. This study has implications for English language teachers and material developers to benefit customized bimodal subtitles as a mnemonic tool for better comprehension, retention and recall of aural contents in videos via Computer Assisted Language Teaching approach.

  6. Retention and failure morphology of prefabricated posts

    DEFF Research Database (Denmark)

    Sahafi, Alireza; Peutzfeldt, Anne; Asmussen, Erik

    2004-01-01

    PURPOSE: This study evaluated the effect of cement, post material, surface treatment, and shape (1) on the retention of posts luted in the root canals of extracted human teeth and (2) on the failure morphology. MATERIALS AND METHODS: Posts of titanium alloy (ParaPost XH), glass fiber (Para...... at 37 degrees C for 7 days, retention was determined by extraction of the posts. Failure morphology of extracted posts was analyzed and quantified stereomicroscopically. RESULTS: Type of luting cement, post material, and shape of post influenced the retention and failure morphology of the posts. Because...

  7. Relationship between potassium intake and radiocesium retention in the reindeer

    International Nuclear Information System (INIS)

    Holleman, D.F.; Luick, J.R.

    1975-01-01

    The effect of dietary potassium on radiocesium retention was studied in reindeer fed winter diets of lichens. Potassium added to the diet markedly decreased radiocesium retention; this suggests that seasonal changes in cesium retention observed earlier in reindeer might be caused largely by nutritional factors. Data indicate that a 20-fold increase in dietary potassium results in a 2-fold decrease in radiocesium retention

  8. Mechanisms of gas retention and release: Experimental results for Hanford single-shell waste tanks 241-A-101, 241-S-106, and 241-U-103

    International Nuclear Information System (INIS)

    Rassat, S.D.; Caley, S.M.; Bredt, P.R.; Gauglitz, P.A.; Rinehart, D.E.; Forbes, S.V.

    1998-09-01

    The 177 underground waste storage tanks at the Hanford Site contain millions of gallons of radioactive waste resulting from the purification of nuclear materials and related processes. Through various mechanisms, flammable gas mixtures of hydrogen, ammonia, methane, and nitrous oxide are generated and retained in significant quantities within the waste in many (∌25) of these tanks. The potential for large releases of retained gas from these wastes creates a flammability hazard. It is a critical component of the effort to understand the flammability hazard and a primary goal of this laboratory investigation to establish an understanding of the mechanisms of gas retention and release in these wastes. The results of bubble retention experimental studies using waste samples from several waste tanks and a variety of waste types support resolution of the Flammable Gas Safety Issue. Gas bubble retention information gained in the pursuit of safe storage will, in turn, benefit future waste operations including salt-well pumping, waste transfers, and sluicing/retrieval

  9. ARTIST: An International Project Investigating Aerosol Retention in a Ruptured Steam Generator

    International Nuclear Information System (INIS)

    Guentay, S.; Dehbi, A.; Suckow, D.; Birchley, J.

    2002-01-01

    conditions, 5) Aerosol retention in the bundle section under wet conditions, 6) Droplet retention in separator and dryer sections and 7) Integral tests to examine overall retention in the SG unit. The project will investigate phenomena at the separate effect and integral levels, and will also address selected accident management (AM) issues. The kick-off experiments are scheduled for the first half of 2002, and some early results will be summarized at the meeting. (authors)

  10. Post retention and post/core shear bond strength of four post systems.

    Science.gov (United States)

    Stockton, L W; Williams, P T; Clarke, C T

    2000-01-01

    As clinicians we continue to search for a post system which will give us maximum retention while maximizing resistance to root fracture. The introduction of several new post systems, with claims of high retentive and resistance to root fracture values, require that independent studies be performed to evaluate these claims. This study tested the tensile and shear dislodgment forces of four post designs that were luted into roots 10 mm apical of the CEJ. The Para Post Plus (P1) is a parallel-sided, passive design; the Para Post XT (P2) is a combination active/passive design; the Flexi-Post (F1) and the Flexi-Flange (F2) are active post designs. All systems tested were stainless steel. This study compared the test results of the four post designs for tensile and shear dislodgment. All mounted samples were loaded in tension until failure occurred. The tensile load was applied parallel to the long axis of the root, while the shear load was applied at 450 to the long axis of the root. The Flexi-Post (F1) was significantly different from the other three in the tensile test, however, the Para Post XT (P2) was significantly different to the other three in the shear test and had a better probability for survival in the Kaplan-Meier survival function test. Based on the results of this study, our recommendation is for the Para Post XT (P2).

  11. Physiologically active hydrogel (in situ gel of sparfloxacin and its evaluation for ocular retention using gamma scintigraphy

    Directory of Open Access Journals (Sweden)

    Himanshu Gupta

    2015-01-01

    Full Text Available Objective: Due to the structure and physiological barrier of eye, only 1% of instilled dose is available for action on the corneal surface. In this work, we developed and evaluated chitosan (pH sensitive and gellan gum (ion sensitive in situ gel of sparfloxacin to improve precorneal residence time. Materials and Methods: A protocol for radiolabeling of sparfloxacin with Tc-99m was optimized to study the ocular retention using gamma scintigraphy technique. Results: The clear formulation was developed. In vitro release showed a sustained and prolonged release compared to plain eye drop solution. Dynamic and static gamma scintigraphy showed better retention than plain eye drops. The ocular tolerance test (henâ€Čs egg test-chorioallantoic membrane test and infra-red study showed that the formulation is nonirritant and can be used as ocular vehicle. Conclusion: Radiolabel protocol for sparfloxacin was successfully developed and evaluated on ocular retention studies of developed in situ gel. The developed in situ gel is non irritant and can go further with clinical evaluation.

  12. Non-aqueous retention measurement: ultrafiltration behaviour of polystyrene solutions and colloidal silver particles

    NARCIS (Netherlands)

    Beerlage, M.A.M.; Beerlage, M.A.M.; Heijnen, M.L.; Mulder, M.H.V.; Smolders, C.A.; Smolders, C.A.; Strathmann, H.

    1996-01-01

    The retention behaviour of polyimide ultrafiltration membranes was investigated using dilute solutions of polystyrene in ethyl acetate as test solutions. It is shown that flow-induced deformation of the polystyrene chains highly affects the membrane retention. This coil-stretch transition is not

  13. Rapidly disintegrating vagina retentive cream suppositories of progesterone: development, patient satisfaction and in vitro/in vivo studies.

    Science.gov (United States)

    Bendas, Ehab Rasmy; Basalious, Emad B

    2016-01-01

    Our objective was to develop novel vagina retentive cream suppositories (VRCS) of progesterone having rapid disintegration and good vaginal retention. VRCS of progesterone were prepared using oil in water (o/w) emulsion of mineral oil or theobroma oil in hard fat and compared with conventional vaginal suppositories (CVS) prepared by hard fat. VRCS formulations were tested for content uniformity, disintegration, melting range, in vitro release and stability studies. The most stable formulation (VRCS I) was subjected to scaling-up manufacturing and patients' satisfaction test. The rapid disintegration, good retentive properties are applicable through the inclusion of emulsified theobroma oil rather than hydrophilic surfactant into the hard fat bases. The release profile of progesterone from VRCS I showed a biphasic pattern due to the formation of progesterone reservoir in the emulsified theobroma oil. All volunteers involved in patients' satisfaction test showed high satisfactory response to the tested formulation (VRCS). The in vivo pharmacokinetic study suggests that VRCS of progesterone provided higher rate and extent of absorption compared to hard fat based suppositories. Our results proposed that emulsified theobroma oil could be promising to solve the problems of poor patients' satisfaction and variability of drug absorption associated with hard fat suppositories.

  14. Retention of HIV-Positive Adolescents in Care: A Quality Improvement Intervention in Mid-Western Uganda

    Directory of Open Access Journals (Sweden)

    Jonathan Izudi

    2018-01-01

    Full Text Available Background. Low retention of HIV-positive adolescents in care is a major problem across HIV programs. Approximately 70% of adolescents were nonretained in care at Katooke Health Center, Mid-Western Uganda. Consequently, a quality improvement (QI project was started to increase retention from 29.3% in May 2016 to 90% in May 2017. Methods. In May 2016, we analyzed data for retention, prioritized gaps with theme-matrix selection, analyzed root causes with fishbone diagram, developed site-specific improvement changes and prioritized with countermeasures matrix, and implemented improvement changes with Plan-Do-Study-Act (PDSA. Identified root causes were missing follow-up strategy, stigma and discrimination, difficult health facility access, and missing scheduled appointments. Interventions tested included generating list of adolescents who missed scheduled appointments, use of mobile phone technology, and linkage of adolescents to nearest health facilities (PDSA 1, Adolescent Only Clinic (PDSA 2, and monthly meetings to address care and treatment challenges (PDSA 3. Results. Retention increased from 17 (29.3% in May 2016 to 60 (96.7% in August 2016 and was maintained above 90% until May 2017 (with exception of February and May 2017 recording 100% retention levels. Conclusion. Context specific, integrated, adolescent-centered interventions implemented using QI significantly improved retention in Mid-Western Uganda.

  15. Urinary retention in women.

    Science.gov (United States)

    Juma, Saad

    2014-07-01

    This review is a summary of the most pertinent published studies in the literature in the last 18 months that address cause, diagnosis, and management of urinary retention in women. Symptoms, uroflow, and pressure-flow studies have a low predictive value for and do not correlate with elevated postvoid residual urine (PVR). Anterior and posterior colporrhaphy do not cause de-novo bladder outlet obstruction in the majority of patients with elevated PVR, and the cause of elevated PVR may be other factors such as pain or anxiety causing abnormal relaxation of the pelvic floor and contributing to voiding difficulty. The risk of urinary retention in a future pregnancy after mid-urethral sling (MUS) is small. The risk of urinary tract infection and urinary retention after chemodenervation of the bladder with onabotulinumtoxin-A (100 IU) in patients with non-neurogenic urge incontinence is 33 and 5%, respectively. There is a lack of consensus among experts on the timing of sling takedown in the management of acute urinary retention following MUS procedures. There has been a significant progress in the understanding of the causation of urinary retention. Important areas that need further research (basic and clinical) are post-MUS and pelvic organ prolapse repair urinary retention and obstruction, and urinary retention owing to detrusor underactivity.

  16. CCTF CORE I test results

    International Nuclear Information System (INIS)

    Murao, Yoshio; Sudoh, Takashi; Akimoto, Hajime; Iguchi, Tadashi; Sugimoto, Jun; Fujiki, Kazuo; Hirano, Kenmei

    1982-07-01

    This report presents the results of the following CCTF CORE I tests conducted in FY. 1980. (1) Multi-dimensional effect test, (2) Evaluation model test, (3) FLECHT coupling test. On the first test, one-dimensional treatment of the core thermohydrodynamics was discussed. On the second and third tests, the test results were compared with the results calculated by the evaluation model codes and the results of the corresponding FLECHT-SET test (Run 2714B), respectively. The work was performed under contracts with the Atomic Energy Bureau of Science and Technology Agency of Japan. (author)

  17. Artificial neural network prediction of quantitative structure - retention relationships of polycyclic aromatic hydocarbons in gas chromatography

    Directory of Open Access Journals (Sweden)

    SNEZANA SREMAC

    2005-11-01

    Full Text Available A feed-forward artificial neural network (ANN model was used to link molecular structures (boiling points, connectivity indices and molecular weights and retention indices of polycyclic aromatic hydrocarbons (PAHs in linear temperature-programmed gas chromatography. A randomly taken subset of PAH retention data reported by Lee et al. [Anal. Chem. 51 (1979 768], containing retention index data for 30 PAHs, was used to make the ANN model. The prediction ability of the trained ANN was tested on unseen data for 18 PAHs from the same article, as well as on the retention data for 7 PAHs experimentally obtained in this work. In addition, two different data sets with known retention indices taken from the literature were analyzed by the same ANN model. It has been shown that the relative accuracy as the degree of agreement between the measured and the predicted retention indices in all testing sets, for most of the studied PAHs, were within the experimental error margins (±3%.

  18. Factors affecting the retention of methyl iodide by iodide-impregnated carbon

    International Nuclear Information System (INIS)

    Hyder, M.L.; Malstrom, R.A.

    1991-01-01

    This paper comprises two sets of studies of methyl iodide retention by iodide-impregnated carbon. In the first of these, the retention of the methyl iodide on the carbon surface and its subsequent evolution were observed directly by a technique of combustion and phosphorescence. In the second, the methyl iodide retention in a standard test was compared with surface area measurements and the concentration of unreacted iodine. A correlation among these parameters was identified and characterized. Carbon quality was varied through the selection of used material with differing service histories. Air from the Savannah River Site reactor buildings is vented through carbon beds for control of radioiodine before release to the atmosphere. The carbon used is North American Carbon Co. type GX-176 coconut shell carbon impregnated with 1% triethylenedimaine (TEDA) and 2% potassium iodide by weight. Replacement intervals for the carbon have been as long as thirty months. Analysis of samples withdrawn at much shorter times has shown that the TEDA is lost after a few months, and the performance of the carbon for methyl iodide retention is dependent on the iodide impregnant. Efficient methyl iodide retention is not a requirement for carbon in this service; however, methyl iodide retention as measured by the ASTM Test D3803 (method B) has been found to correlate well with other desirable properties of the carbon such as radiation stability. The studies undertaken here were intended to shed light on the changes taking place in this carbon during long-term service and to provide a basis for simpler measurements of carbon quality

  19. Examining the Relations among Student Motivation, Engagement, and Retention in a MOOC: A Structural Equation Modeling Approach

    Directory of Open Access Journals (Sweden)

    Yao Xiong

    2015-09-01

    Full Text Available Students who are enrolled in MOOCs tend to have different motivational patterns than fee-paying college students. A majority of MOOC students demonstrate characteristics akin more to "tourists" than formal learners. As a consequence, MOOC students’ completion rate is usually very low. The current study examines the relations among student motivation, engagement, and retention using structural equation modeling and data from a Penn State University MOOC. Three distinct types of motivation are examined: intrinsic motivation, extrinsic motivation, and social motivation. Two main hypotheses are tested: (a motivation predicts student course engagement; and (b student engagement predicts their retention in the course. The results show that motivation is significantly predictive of student course engagement. Furthermore, engagement is a strong predictor of retention. The findings suggest that promoting student motivation and monitoring individual students’ online activities might improve course retention

  20. Effects of Different Types of True-False Questions on Memory Awareness and Long-Term Retention

    Science.gov (United States)

    Schaap, Lydia; Verkoeijen, Peter; Schmidt, Henk

    2014-01-01

    This study investigated the effects of two different true-false questions on memory awareness and long-term retention of knowledge. Participants took four subsequent knowledge tests on curriculum learning material that they studied at different retention intervals prior to the start of this study (i.e. prior to the first test). At the first and


  1. The acquisition and retention of ECG interpretation skills after a standardized web-based ECG tutorial

    DEFF Research Database (Denmark)

    Rolskov Bojsen, Signe; RĂ€der, Sune Bernd Emil Werner; Holst, Anders Gaardsdal

    2015-01-01

    BACKGROUND: Electrocardiogram (ECG) interpretation is of great importance for patient management. However, medical students frequently lack proficiency in ECG interpretation and rate their ECG training as inadequate. Our aim was to examine the effect of a standalone web-based ECG tutorial...... and to assess the retention of skills using multiple follow-up intervals. METHODS: 203 medical students were included in the study. All participants completed a pre-test, an ECG tutorial, and a post-test. The participants were also randomised to complete a retention-test after short (2-4 weeks), medium (10.......6), respectively). When comparing the pre-test to retention-test delta scores, junior students had learned significantly more than senior students (junior students improved 10.7 points and senior students improved 4.7 points, p = 0.003). CONCLUSION: A standalone web-based ECG tutorial can be an effective means...

  2. Investigating the Role of Pop Songs on Vocabulary Recall, Attitude and Retention of Iranian EFL Learners: The Case of Gender

    Directory of Open Access Journals (Sweden)

    Pouya Shakerian

    2016-04-01

    Full Text Available Pop songs are, in fact, an ideal source for incidental vocabulary learning because teenagers often spend large amounts of their free time listening to music and in particular to pop songs. Employing an experimental approach, this study attempted to investigate the role of pop songs on vocabulary recall, attitude and retention of Iranian advanced adult EFL learners based on their gender. In so doing a language placement test (Quick Oxford Placement Test was administered to 100 male and female language learners studying English at different language institutes in Esfahan, Iran. Ultimately, 60 advanced learners (30 males - 30 females were selected by leaving out the students of other levels of proficiency and randomly divided into two relatively homogenous groups as musical and non-musical groups. While the students of musical group (=30 were taught the new vocabulary in the syllabus through 60 different pop songs chosen by themselves through a questionnaire, the students of the non-musical group (n=30 were taught new vocabulary without using the songs. The participants were examined based on an English vocabulary test developed by the researchers, which probed into the learners’ vocabulary recall. A questionnaire was also used to investigate the attitude of the learners towards the instruction. A month later the vocabulary test was re-administered as a delayed retention test and obtained data were statistically analyzed. The results of t-tests demonstrated that the musical group outscored the non-musical group on vocabulary recall and retention. The results also showed the male learners perform better than the females. Keywords: incidental vocabulary, pop songs, vocabulary recall, attitude, retention

  3. Rainwater harvesting and green area retention potential detection using commercial unmanned aerial vehicles

    Science.gov (United States)

    Kamnik, Rok; Grajfoner, Blanka; Butyrin, Andrey; Nekrep Perc, Matjaz

    2017-10-01

    The objective of this work is to use simple photogrammetry to evaluate rainwater harvesting and green area retention potential in Maribor, Slovenia city centre. Several sources of remote sensing data have been described and a field test with semi-professional drone was performed by means of computer evaluation of rainwater harvesting and green area retention potential. Some of the most important design parameters for rainwater harvesting systems as roof area and slope and available green areas were identified and evaluated. The results have shown that even semi-professional low budget drones can be successfully used for mapping areas of interest. The results of six-minute flight over twelve hectares of Maribor city centre were comparable with professional results of plane remote sensing. Image segmentation from orthomosaic together with elevation model has been used to detect roofs and green areas.

  4. Novel word retention in bilingual and monolingual speakers

    Directory of Open Access Journals (Sweden)

    Pui Fong eKan

    2014-09-01

    Full Text Available 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, Sadagopan, Janich, & Andrade, 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.

  5. Novel word retention in bilingual and monolingual speakers.

    Science.gov (United States)

    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.

  6. QSPR Study of the Retention/release Property of Odorant Molecules in Water Using Statistical Methods

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    Assia Belhassan

    2017-10-01

    Full Text Available An integrated approach physicochemistry and structures property relationships has been carried out to study the odorant molecules retention/release phenomenon in the water. This study aimed to identify the molecular properties (molecular descriptors that govern this phenomenon assuming that modifying the structure leads automatically to a change in the retention/release property of odorant molecules. ACD/ChemSketch, MarvinSketch, and ChemOffice programs were used to calculate several molecular descriptors of 51 odorant molecules (15 alcohols, 11 aldehydes, 9 ketones and 16 esters. A total of 37 molecules (2/3 of the data set were placed in the training set to build the QSPR models, whereas the remaining, 14 molecules (1/3 of the data set constitute the test set. The best descriptors were selected to establish the quantitative structure property relationship (QSPR of the retention/release property of odorant molecules in water using multiple linear regression (MLR, multiple non-linear regression (MNLR and an artificial neural network (ANN methods. We propose a quantitative model according to these analyses. The models were used to predict the retention/release property of the test set compounds, and agreement between the experimental and predicted values was verified. The descriptors showed by QSPR study are used for study and designing of new compounds. The statistical results indicate that the predicted values are in good agreement with the experimental results. To validate the predictive power of the resulting models, external validation multiple correlation coefficient was calculated and has both in addition to a performant prediction power, a favorable estimation of stability. DOI: http://dx.doi.org/10.17807/orbital.v9i4.978 

  7. Cr(VI) retention and transport through Fe(III)-coated natural zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Du, Gaoxiang [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Li, Zhaohui, E-mail: li@uwp.edu [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Geosciences Department, University of Wisconsin-Parkside, Kenosha, WI 53144 (United States); Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China); Liao, Libing [School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Hanson, Renee; Leick, Samantha; Hoeppner, Nicole [Geosciences Department, University of Wisconsin-Parkside, Kenosha, WI 53144 (United States); Jiang, Wei-Teh [Department of Earth Sciences, National Cheng Kung University, 1 University Road, Tainan 70101, Taiwan (China)

    2012-06-30

    Graphical abstract: Breakthrough curves of Cr(VI) from columns packed with raw zeolite (a) and Fe(III)-zeolite (b). The solid line in (b) is the HYDRUS-1D fit to the observed data with adsorption term only, while the dashed line in (b) includes a reduction term in the HYDRUS-1D fit. Highlights: Black-Right-Pointing-Pointer Zeolite modified with Fe(III) could be used for adsorption and retention of Cr(VI). Black-Right-Pointing-Pointer The Fe present on zeolite was in an amorphous Fe(OH){sub 3} form. Black-Right-Pointing-Pointer A Cr(VI) adsorption capacity of 82 mg/kg was found on Fe(III)-zeolite. Black-Right-Pointing-Pointer A Cr(VI) retardation factor of 3 or 5 was determined from column and batch studies. - Abstract: Cr(VI) is a group A chemical based on the weight of evidence of carcinogenicity. Its transport and retention in soils and groundwater have been studied extensively. Zeolite is a major component in deposits originated from volcanic ash and tuff after alteration. In this study, zeolite aggregates with the particle size of 1.4-2.4 mm were preloaded with Fe(III). The influence of present Fe(III) on Cr(VI) retention by and transport through zeolite was studied under batch and column experiments. The added Fe(III) resulted in an enhanced Cr(VI) retention by the zeolite with a capacity of 82 mg/kg. The Cr(VI) adsorption on Fe(III)-zeolite followed a pseudo-second order kinetically and the Freundlich adsorption isotherm thermodynamically. Fitting the column experimental data to HYDRUS-1D resulted in a retardation factor of 3 in comparison to 5 calculated from batch tests at an initial Cr(VI) concentration of 3 mg/L. The results from this study showed that enhanced adsorption and retention of Cr(VI) may happen in soils derived from volcanic ash and tuff that contains significant amounts of zeolite with extensive Fe(III) coating.

  8. Pigeons exhibit higher accuracy for chosen memory tests than for forced memory tests in duration matching-to-sample.

    Science.gov (United States)

    Adams, Allison; Santi, Angelo

    2011-03-01

    Following training to match 2- and 8-sec durations of feederlight to red and green comparisons with a 0-sec baseline delay, pigeons were allowed to choose to take a memory test or to escape the memory test. The effects of sample omission, increases in retention interval, and variation in trial spacing on selection of the escape option and accuracy were studied. During initial testing, escaping the test did not increase as the task became more difficult, and there was no difference in accuracy between chosen and forced memory tests. However, with extended training, accuracy for chosen tests was significantly greater than for forced tests. In addition, two pigeons exhibited higher accuracy on chosen tests than on forced tests at the short retention interval and greater escape rates at the long retention interval. These results have not been obtained in previous studies with pigeons when the choice to take the test or to escape the test is given before test stimuli are presented. It appears that task-specific methodological factors may determine whether a particular species will exhibit the two behavioral effects that were initially proposed as potentially indicative of metacognition.

  9. Leadership training to improve nurse retention.

    Science.gov (United States)

    Wallis, Allan; Kennedy, Kathy I

    2013-05-01

    This paper discusses findings from an evaluation of a training programme designed to promote collaborative, team-based approaches to improve nurse retention within health care organizations. A year-long leadership training programme was designed and implemented to develop effective teams that could address retention challenges in a diverse set of organizations in Colorado ranging from public, private to non-profit. An evaluation, based on a combination of participant observation, group interviews, and the use of standardized tests measuring individual emotional intelligence and team dynamics was conducted to assess the effectiveness of the training programme. What role do the emotional intelligence of individual members and organizational culture play in team effectiveness? Out of five teams participating in the training programme, two performed exceptionally well, one experienced moderate success and two encountered significant problems. Team dynamics were significantly affected by the emotional intelligence of key members holding supervisory positions and by the existing culture and structure of the participating organizations. Team approaches to retention hold promise but require careful development and are most likely to work where organizations have a collaborative problem-solving environment. © 2012 Blackwell Publishing Ltd.

  10. Shear force bond analysis between acrylic resin bases and retention framework (open- and mesh-type)

    Science.gov (United States)

    Royhan, A.; Indrasari, M.; Masulili, C.

    2017-08-01

    Occlusions between teeth and the activity of the muscles around an artificial tooth during mastication create a force on dentures. This force causes friction between acrylic resin bases and retention frameworks that can lead to the complete loss of the acrylic resin base from the framework. The purpose of this study was to analyze the design of retention frameworks and determine which ones have a better resistance to shear forces in order to prevent the loss of heat cured acrylic resin base (HCARB). Six samples each of open-and mesh-type retention frameworks, both types made of Co-Cr material, and HCARB, were shear tested by means of a universal testing machine. The average shear force required to release the HCARB for mesh-type retention frameworks was 28.84 kgf, and the average for the open-type was 26.52 kgf. There was no significant difference between the shear forces required to remove HCARB from open- and mesh-type retention frameworks.

  11. Trends in CD4 Count Testing, Retention in Pre-ART Care, and ART Initiation Rates over the First Decade of Expansion of HIV Services in Haiti.

    Directory of Open Access Journals (Sweden)

    Serena P Koenig

    Full Text Available High attrition during the period from HIV testing to antiretroviral therapy (ART initiation is widely reported. Though treatment guidelines have changed to broaden ART eligibility and services have been widely expanded over the past decade, data on the temporal trends in pre-ART outcomes are limited; such data would be useful to guide future policy decisions.We evaluated temporal trends and predictors of retention for each step from HIV testing to ART initiation over the past decade at the GHESKIO clinic in Port-au-Prince Haiti. The 24,925 patients >17 years of age who received a positive HIV test at GHESKIO from March 1, 2003 to February 28, 2013 were included. Patients were followed until they remained in pre-ART care for one year or initiated ART.24,925 patients (61% female, median age 35 years were included, and 15,008 (60% had blood drawn for CD4 count within 12 months of HIV testing; the trend increased over time from 36% in Year 1 to 78% in Year 10 (p500 cells/mm3, respectively. The trend increased over time for each CD4 strata, and in Year 10, 94%, 95%, 79%, and 74% were retained in pre-ART care or initiated ART for each CD4 strata. Predictors of pre-ART attrition included male gender, low income, and low educational status. Older age and tuberculosis (TB at HIV testing were associated with retention in care.The proportion of patients completing assessments for ART eligibility, remaining in pre-ART care, and initiating ART have increased over the last decade across all CD4 count strata, particularly among patients with CD4 count ≀350 cells/mm3. However, additional retention efforts are needed for patients with higher CD4 counts.

  12. Retention of fissure sealants in young permanent molars affected by dental fluorosis: a 12-month clinical study.

    Science.gov (United States)

    Hasanuddin, S; Reddy, E R; Manjula, M; Srilaxmi, N; Rani, S T; Rajesh, A

    2014-10-01

    To evaluate and compare retention and caries occurance following placement of Clinpro and FUJI VII fissure sealants, by two different techniques simultaneously in unsealed, contralateral young permanent molars of 7- to 10-year-old children affected by mild to moderate dental fluorosis at various recall intervals of 1 week, 1, 3, 6 and 12 months. 80 schoolchildren with mild to moderate dental fluorosis were assigned to Group A and Group B with 40 children in each group. In Group A Clinpro fissure sealant and in Group B Fuji VII fissure sealant was used. In both the groups fissure sealants were applied by conventional fissure sealant technique (CST) on one side and enameloplasty sealant technique (EST) on the other side of the same arch. The applied fissure sealants were evaluated clinically for retention and caries incidence. Clinpro fissure sealant showed a retention rate of 95% when compared with Fuji VII (57.5%) at the end of 12 months, which was statistically significant. Regarding techniques, EST showed better results than CST in both the groups. Comparison of groups with respect to retention and techniques at different time periods was performed using Mann-Whitney U test (p < 0.05). Comparison of different time periods with respect to retention and technique in all the groups was performed using Wilcoxon matched pairs test by ranks (p < 0.05). Clinpro fissure sealant showed better retention at all treatment intervals, when compared with Fuji VII. Further follow-up is required to study the efficacy of the fissure sealant placement techniques.

  13. A phenomenological retention tank model using settling velocity distributions.

    Science.gov (United States)

    Maruejouls, T; Vanrolleghem, P A; Pelletier, G; Lessard, P

    2012-12-15

    Many authors have observed the influence of the settling velocity distribution on the sedimentation process in retention tanks. However, the pollutants' behaviour in such tanks is not well characterized, especially with respect to their settling velocity distribution. This paper presents a phenomenological modelling study dealing with the way by which the settling velocity distribution of particles in combined sewage changes between entering and leaving an off-line retention tank. The work starts from a previously published model (Lessard and Beck, 1991) which is first implemented in a wastewater management modelling software, to be then tested with full-scale field data for the first time. Next, its performance is improved by integrating the particle settling velocity distribution and adding a description of the resuspension due to pumping for emptying the tank. Finally, the potential of the improved model is demonstrated by comparing the results for one more rain event. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Retention of fundamental surgical skills learned in robot-assisted surgery.

    Science.gov (United States)

    Suh, Irene H; Mukherjee, Mukul; Shah, Bhavin C; Oleynikov, Dmitry; Siu, Ka-Chun

    2012-12-01

    Evaluation of the learning curve for robotic surgery has shown reduced errors and decreased task completion and training times compared with regular laparoscopic surgery. However, most training evaluations of robotic surgery have only addressed short-term retention after the completion of training. Our goal was to investigate the amount of surgical skills retained after 3 months of training with the da Vinciℱ Surgical System. Seven medical students without any surgical experience were recruited. Participants were trained with a 4-day training program of robotic surgical skills and underwent a series of retention tests at 1 day, 1 week, 1 month, and 3 months post-training. Data analysis included time to task completion, speed, distance traveled, and movement curvature by the instrument tip. Performance of the participants was graded using the modified Objective Structured Assessment of Technical Skills (OSATS) for robotic surgery. Participants filled out a survey after each training session by answering a set of questions. Time to task completion and the movement curvature was decreased from pre- to post-training and the performance was retained at all the corresponding retention periods: 1 day, 1 week, 1 month, and 3 months. The modified OSATS showed improvement from pre-test to post-test and this improvement was maintained during all the retention periods. Participants increased in self-confidence and mastery in performing robotic surgical tasks after training. Our novel comprehensive training program improved robot-assisted surgical performance and learning. All trainees retained their fundamental surgical skills for 3 months after receiving the training program.

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

    Science.gov (United States)

    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.

  16. Soil Water Retention Curve

    Science.gov (United States)

    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

  17. Computer game-based and traditional learning method: a comparison regarding students’ knowledge retention

    Directory of Open Access Journals (Sweden)

    Rondon Silmara

    2013-02-01

    Full Text Available Abstract Background Educational computer games are examples of computer-assisted learning objects, representing an educational strategy of growing interest. Given the changes in the digital world over the last decades, students of the current generation expect technology to be used in advancing their learning requiring a need to change traditional passive learning methodologies to an active multisensory experimental learning methodology. The objective of this study was to compare a computer game-based learning method with a traditional learning method, regarding learning gains and knowledge retention, as means of teaching head and neck Anatomy and Physiology to Speech-Language and Hearing pathology undergraduate students. Methods Students were randomized to participate to one of the learning methods and the data analyst was blinded to which method of learning the students had received. Students’ prior knowledge (i.e. before undergoing the learning method, short-term knowledge retention and long-term knowledge retention (i.e. six months after undergoing the learning method were assessed with a multiple choice questionnaire. Students’ performance was compared considering the three moments of assessment for both for the mean total score and for separated mean scores for Anatomy questions and for Physiology questions. Results Students that received the game-based method performed better in the pos-test assessment only when considering the Anatomy questions section. Students that received the traditional lecture performed better in both post-test and long-term post-test when considering the Anatomy and Physiology questions. Conclusions The game-based learning method is comparable to the traditional learning method in general and in short-term gains, while the traditional lecture still seems to be more effective to improve students’ short and long-term knowledge retention.

  18. The COLIMA experiment on aerosol retention in containment leak paths under severe nuclear accidents

    Energy Technology Data Exchange (ETDEWEB)

    Parozzi, Flavio, E-mail: flavio.parozzi@rse-web.it [RSE, Power Generation Department, via Rubattino 54, I-20134 Milano (Italy); Caracciolo, Eduardo D.J., E-mail: eduardo.caracciolo@rse-web.it [RSE, Power Generation Department, via Rubattino 54, I-20134 Milano (Italy); Journeau, Christophe, E-mail: christophe.journeau@cea.fr [CEA Cadarache (France); Piluso, Pascal, E-mail: pascal.piluso@cea.fr [CEA Cadarache (France)

    2013-08-15

    Highlights: â–ș Experiment investigating aerosol retention within concrete containment cracks under nuclear severe accident conditions. â–ș Provided representative conditions of the aerosols suspended inside the containment of PWRs under a severe accident. â–ș Prototypical aerosol particles generated with a thermite reaction and transported through the crack sample reproducing surface characteristics, temperature, pressure drop and gas leakage. â–ș The results indicate the significant retention due to zig-zag path. -- Abstract: CEA and RSE managed an experimental research concerning the investigation of aerosol retention within concrete containment cracks under severe accident conditions. The main experiment was carried out in November 2008 with aerosol generated from the COLIMA facility and a sample of cracked concrete with defined geometric characteristics manufactured by RSE. The facility provided representative conditions of the aerosols suspended inside the containment of PWRs under a severe accident. Prototypical aerosol particles were generated with a thermite reaction and transported through the crack sample, where surface characteristics, temperature, pressure drop and gas leakage were properly reproduced. The paper describes the approach adopted for the preparation of the cracked concrete sample and the dimensioning of the experimental apparatus, the test procedure and the measured parameters. The preliminary results, obtained from this single test, are also discussed in the light of the present knowledge about aerosol phenomena and the theoretical analyses of particle behaviour with the crack path.

  19. Short-term retention of pictures and words as a function of type of distraction and length of delay interval.

    Science.gov (United States)

    Pellegrino, J W; Siegel, A W; Dhawan, M

    1976-01-01

    Picture and word triads were tested in a Brown-Peterson short-term retention task at varying delay intervals (3, 10, or 30 sec) and under acoustic and simultaneous acoustic and visual distraction. Pictures were superior to words at all delay intervals under single acoustic distraction. Dual distraction consistently reduced picture retention while simultaneously facilitating word retention. The results were interpreted in terms of the dual coding hypothesis with modality-specific interference effects in the visual and acoustic processing systems. The differential effects of dual distraction were related to the introduction of visual interference and differential levels of functional acoustic interference across dual and single distraction tasks. The latter was supported by a constant 2/1 ratio in the backward counting rates of the acoustic vs. dual distraction tasks. The results further suggest that retention may not depend on total processing load of the distraction task, per se, but rather that processing load operates within modalities.

  20. Evaluation of 131I retention in several adsorbers

    International Nuclear Information System (INIS)

    Catanoso, Marcela F.; Osso Junior, Joao Alberto

    2011-01-01

    Several iodine radioisotopes are used in nuclear medicine for treatment and diagnostic purposes. The radioisotope 131 I is used both in diagnosis and therapy due to its physical characteristics of decay by ÎČ - and its Îł-ray emissions suitable for diagnosis. It is routinely produced at IPEN through the irradiation of TeO 2 targets in the IEA-R1m nuclear reactor. After the irradiation, the 131 I is separated by dry distillation, where the targets are put in an oven, heated at 760 deg C for 2 hours and the 131 I, volatile, is carried by an O 2 gas stream. The aim of this work was to evaluate the retention and elution of 131 I samples produced at IPEN in several adsorbers as part of a project aiming the purification of these radioisotopes, allowing the labeling of biomolecules. Samples of 131 I were used for retention and elution studies with the following adsorbers: commercial cartridges, anionic resin columns and cationic resin column. The results showed that Ag cartridges and anionic resins Dowex 1X8, Dowex 3 and IRA 400 had a great iodine retention but no elution after using specific eluents. The QMA light, acid alumina, neutral alumina and cationic resin Dowex 50WX4 showed high retention and elution and QMA plus and cationic resin Dowex 50WX8 and Dowex 50WX12 had a good retention but lower elution. Regarding to the better retention and elution, Ag cartridges and resins showed a higher percentage of iodine retention but lower elution yield and QMA light, acid and neutral alumina cartridges showed better results. (author)

  1. Factors Determining Student Retention of Economic Knowledge after Completing the Principles-of-Microeconomics Course.

    Science.gov (United States)

    Kohen, Andrew I.; Kipps, Paul H.

    1979-01-01

    Reports results of a study of economics students to test the effect of time and other factors affecting retention, to develop an instrument to measure the rate of depreciation of the student's stock of economic knowledge, and to explore the implications of findings for the student's academic planning. (Author/KC)

  2. Grades, Student Satisfaction and Retention in Online and Face-to-Face Introductory Psychology Units: A Test of Equivalency Theory

    Science.gov (United States)

    Garratt-Reed, David; Roberts, Lynne D.; Heritage, Brody

    2016-01-01

    There has been a recent rapid growth in the number of psychology courses offered online through institutions of higher education. The American Psychological Association has highlighted the importance of ensuring the effectiveness of online psychology courses (Halonen et al., 2013). Despite this, there have been inconsistent findings regarding student grades, satisfaction, and retention in online psychology units. Equivalency Theory (Simonson, 1999; Simonson et al., 1999) posits that online and classroom-based learners will attain equivalent learning outcomes when equivalent learning experiences are provided. We present a study of an online introductory psychology unit designed to provide equivalent learning experiences to the pre-existing face-to-face version of the unit. Using quasi-experimental methods, academic performance, student feedback, and retention data from 866 Australian undergraduate psychology students were examined to assess whether the online unit developed to provide equivalent learning experiences produced comparable outcomes to the ‘traditional’ unit delivered face-to-face. Student grades did not significantly differ between modes of delivery, except for a group-work based assessment where online students performed more poorly. Student satisfaction was generally high in both modes of the unit, with group-work the key source of dissatisfaction in the online unit. The results provide partial support for Equivalency Theory. The group-work based assessment did not provide an equivalent learning experience for students in the online unit highlighting the need for further research to determine effective methods of engaging students in online group activities. Consistent with previous research, retention rates were significantly lower in the online unit, indicating the need to develop effective strategies to increase online retention rates. While this study demonstrates successes in presenting students with an equivalent learning experience, we

  3. Faculty ratings of retention strategies for minority nursing students.

    Science.gov (United States)

    Baker, Barbara H

    2010-01-01

    The purpose of this study was to investigate a) the types of retention strategies used by undergraduate nursing programs for the purpose of retaining minority students, b) the rated effectiveness of the strategies, as identified by faculty in those programs, and c) whether there is a relationship between strategies rated as effective and the type of nursing program, baccalaureate (BSN) or associate (AD) degree. Administrator-selected faculty from randomly sampled BSN and AD nursing programs within a 16-state area of the southeastern United States were asked to respond to an online survey regarding the use and effectiveness of retention strategies selected from the literature. Descriptive statistics and chi-square tests for association were used to analyze the data. Of the 14 strategies included in this analysis, faculty availability and timely feedback on tests and clinical performances were used by all undergraduate programs. Organized study groups and peer mentoring were the least used strategies. Faculty from both BSN and AD programs reported using many of the strategies and rated their use as effective overall for minority nursing student retention. The highest rated strategies were those that involved direct interaction of nurse faculty and students.

  4. The influence of a telehealth project on healthcare professional recruitment and retention in remote areas in Mali: A longitudinal study

    Directory of Open Access Journals (Sweden)

    GisĂšle IrĂšne Claudine Mbemba

    2016-05-01

    Full Text Available Objectives: The telehealth project EQUI-ResHuS (in French, Les TIC pour un accĂšs Équitable aux Ressources Humaines en SantĂ© aimed to contribute to more equitable access to care and support practice in remote regions in Mali. This study explored the evolution of perceptions concerning telehealth among healthcare professionals in the four district health centres that participated in the EQUI-ResHus project and identified variables influencing their perceptions of telehealth impact on recruitment and retention of health professionals. Methods: One year after a first survey (T1, a second data collection (T2 was carried out among healthcare professionals using a 91-item questionnaire. Questions assessing telehealth use and perceptions and perceived impact on recruitment and retention of healthcare professionals were rated on a 5-point Likert scale. A total of 10 independent variables were considered for the analyses. A Wilcoxon signed-rank test was performed to detect differences between T1 and T2, and a bivariate linear regression model for repeated measures was carried out to assess the impact of independent variables on dependent variables. Results: There were no noticeable changes in perceptions related to telehealth influence on recruitment and retention. Only access to information and communication technology significantly differed between T1 and T2 according the Wilcoxon rank test (p = 0.001. Perceived influence of telehealth on recruitment and retention was mostly explained by attitude towards telehealth, perceived effect on recruitment and retention and barriers to recruitment and retention. Conclusion: Based on our results, telehealth was perceived as having a positive influence but mostly indirect influence on healthcare professional recruitment and retention. Also, there were no major changes after 1 year of telehealth use.

  5. Mechanistic failure mode investigation and resolution of parvovirus retentive filters.

    Science.gov (United States)

    LaCasse, Daniel; Lute, Scott; Fiadeiro, Marcus; Basha, Jonida; Stork, Matthew; Brorson, Kurt; Godavarti, Ranga; Gallo, Chris

    2016-07-08

    Virus retentive filters are a key product safety measure for biopharmaceuticals. A simplistic perception is that they function solely based on a size-based particle removal mechanism of mechanical sieving and retention of particles based on their hydrodynamic size. Recent observations have revealed a more nuanced picture, indicating that changes in viral particle retention can result from process pressure and/or flow interruptions. In this study, a mechanistic investigation was performed to help identify a potential mechanism leading to the reported reduced particle retention in small virus filters. Permeate flow rate or permeate driving force were varied and analyzed for their impact on particle retention in three commercially available small virus retentive filters. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:959-970, 2016. © 2016 American Institute of Chemical Engineers.

  6. Relationship of Personality Traits to Student Retention

    Science.gov (United States)

    Liang, John Paul

    2010-01-01

    Carl Jung's theory of psychological types has been the basis for the development of personality categorization, including tests such as Myers-Briggs Type Indicator (MBTI). This study analyzed the extent of the relationship between MBTI and Tinto (1993) retention factors that influence Oriental medicine students' choice of staying or dropping out


  7. 40 CFR 80.335 - What gasoline sample retention requirements apply to refiners and importers?

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false What gasoline sample retention... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Gasoline Sulfur Sampling, Testing and Retention Requirements for Refiners and Importers § 80.335 What gasoline sample...

  8. Gas Retention in a Heated Plastic Bonded Explosive (LX-14).

    Energy Technology Data Exchange (ETDEWEB)

    Hobbs, Michael L. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Engineering Sciences Center; Kaneshige, Michael J. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Energetics Components Center; Erikson, William W. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Engineering Sciences Center; Meirs, Kevin T. [U.S. Army Armament Research, Development and Engineering Center (ARDEC), Picatinny Arsenal, NJ (United States)

    2017-09-01

    In prior work, we found that the nitroplasticizer in the plastic bonded explosive PBX 9501 played a crucial role in cookoff, especially when predicting response in larger systems [1]. We have recently completed experiments with a similar explosive, LX-14, that has a relatively nonreactive binder. We expected the ignition times for LX-14 to be longer than PBX 9501 since PBX 9501 has a more reactive binder. However, our experiments show the opposite trend. This paradox can be explained by retention of reactive gases within the interior of LX-14 by the higher strength binder resulting in faster ignition times. In contrast, the binder in PBX 9501 melts at low temperatures and does not retain decomposition gases as well as the LX-14 binder. Retention of reactive gases in LX-14 may also explain the more violent response in oblique impact tests [2] when compared to PBX 9501.

  9. Factors Affecting Staff Retention Strategies Used in Private Syrian Companies during the Crisis

    OpenAIRE

    Gharib, Moaz Nagib; Kahwaji, Ahmad Taha; Elrasheed, Mohammed Osman

    2017-01-01

    The aim of current study is to exam elements influencing retention among employees in private Syrian companies during the crisis. The factors are training and professional development, organizational rewards system, job insecurity and job satisfaction. For this reason, 102 organized surveys were gathered. Obtained results from the study questionnaire were analyzed and examined by using statistical tests as Correlation and Multiple Regression analysis. Results show that training and profession...

  10. Physician recruitment and retention in Manitoba: results from a survey of physicians' preferences for rural jobs.

    Science.gov (United States)

    Witt, Julia

    2017-01-01

    Rural recruitment and retention continues to present challenges to health workforce planners. This paper reports and analyzes the results of a survey sent to physicians in Manitoba, eliciting their opinions regarding rural jobs. A survey was sent to all physicians in Manitoba. Part 1 of the survey included questions about background and demographic information; part 2 was a set of job satisfaction questions regarding respondents' current job; and part 3 included 2 sets of stated-choice questions eliciting preferences for a set of attributes relevant to rural recruitment and retention. Of the 2487 physicians who received surveys, 561 (22.6%) responded. Respondents indicated that income, hours worked and on-call frequency are very important: overall job satisfaction increased with income and decreased with hours worked. Income, hours and on-call frequency were ranked "very important" by the largest proportions of physicians. The estimated compensation for on-call more frequent than 1-in-4 was very high (82% of average income), and additional hours worked were worth $183 per hour. Other attributes that were important included professional interaction, housing availability and community incentives during the first year, which were valued at 11%-31% of annual income. Work-life balance is a key consideration for rural jobs, and there are incentives that can compensate for less desirable attributes.

  11. Measuring in-stream retention of copper by means of constant-rate additions.

    Science.gov (United States)

    Serra, A; Guasch, H; MartĂ­, E; Geiszinger, A

    2009-06-01

    Human practices entail inputs of nutrients and toxicants such as heavy metals to the fluvial ecosystems. While nutrient dynamics in fluvial ecosystems have been widely studied for over three decades, dynamics of toxicants still remain unclear. In this investigation, the nutrient spiraling concept and associated methodologies to quantify nutrient retention in streams were applied to study copper (Cu) dynamics in streams. The present study aimed to quantify total dissolved Cu retention using a simplified system of indoor channels colonized with fluvial biofilms. Cu retention was studied at sub-toxic concentrations to avoid negative/lethal effects on biota. In addition, Cu retention was compared with retention estimates of a macronutrient, phosphate (PO(4)(3-)), which has been widely studied within the context of the nutrient spiraling concept. The methodology used allowed a successful quantification of Cu and PO(4)(3-) retention. The results showed higher retention efficiency for PO(4)(3-) than for Cu. The biofilm played a key role in retaining both solutes. Although retention efficiency for both solutes was higher in the experiments with colonized substrata compared to uncolonized substrata, we found a positive relationship between uptake rate and chlorophyll-a only for PO(4)(3-). Finally, retention efficiency for both solutes was influenced by water discharge, showing lower retention efficiencies under higher flow conditions. These results suggest that the fate and toxic effects of copper on stream biota may be strongly influenced by the prevailing environmental conditions. Our results indicate that the experimental approach considered can provide new insights into the investigation of retention of toxic compounds in fluvial systems and their controlling mechanisms.

  12. The role of glucocorticoids in sodium retention in cirrhotic patients

    DEFF Research Database (Denmark)

    Hansen, Martin HĂžjmark; Kristensen, Steffen Skott; Schaffalitzky de Muckadell, Ove B

    2012-01-01

    sodium retention evident in cirrhosis. The aim was to elucidate the role of glucocorticoids in sodium retention in decompensated cirrhotic patients. Methods. A randomized, double-blind, placebo-controlled, crossover study was performed in nine patients with alcoholic cirrhosis of the liver. A washout....... Conclusion. These results indicate that endogenous glucocorticoids contribute to the sodium retention in patients with alcoholic cirrhosis of the liver....

  13. POSTOPERATIVE URINARY RETENTION AND EARLY REPOSITION OF TENSION-FREE VAGINAL TAPE

    Directory of Open Access Journals (Sweden)

    Marijan LuĆŸnik

    2003-12-01

    Full Text Available Background. The purpose of this article is to show a possible method of treatment of postoperative urinary retention after an initial tension-free vaginal tape.Methods. From December 1999 to May 2003 we performed one hundred TVT procedures at our department, among them five women had postoperative urinary retention evaluated with catheterization. Revision and reposition of tension-free vaginal tape were performed if retention of urine was over 100 ml.Results. Urinary retention after an initial tension-free vaginal tape was successfully treated by early reposition of tension-free vaginal tape. This resulted in immediate residualfree voiding and continence, which remained unchanged at 6 week and 3 month follow-up.Conclusions. Postoperative urinary retention may be treated by reposition instead of dissection or elongation of the tension-free vaginal tape.

  14. Learning sung lyrics aids retention in normal ageing and Alzheimer's disease.

    Science.gov (United States)

    Moussard, Aline; Bigand, Emmanuel; Belleville, Sylvie; Peretz, Isabelle

    2014-01-01

    Previous studies have suggested that presenting to-be-memorised lyrics in a singing mode, instead of a speaking mode, may facilitate learning and retention in normal adults. In this study, seven healthy older adults and eight participants with mild Alzheimer's disease (AD) learned and memorised lyrics that were either sung or spoken. We measured the percentage of words recalled from these lyrics immediately and after 10 minutes. Moreover, in AD participants, we tested the effect of successive learning episodes for one spoken and one sung excerpt, as well as long-term retention after a four week delay. Sung conditions did not influence lyrics recall in immediate recall but increased delayed recall for both groups. In AD, learning slopes for sung and spoken lyrics did not show a significant difference across successive learning episodes. However, sung lyrics showed a slight advantage over spoken ones after a four week delay. These results suggest that singing may increase the load of initial learning but improve long-term retention of newly acquired verbal information. We further propose some recommendations on how to maximise these effects and make them relevant for therapeutic applications.

  15. [Systematic evaluation of retention behavior of carbohydrates in hydrophilic interaction liquid chromatography].

    Science.gov (United States)

    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

  16. The Live program - Results of test L1 and joint analyses on transient molten pool thermal hydraulics

    Energy Technology Data Exchange (ETDEWEB)

    Buck, M.; Buerger, M. [Univ Stuttgart, Inst Kernenerget and Energiesyst, D-70569 Stuttgart (Germany); Miassoedov, A.; Gaus-Liu, X.; Palagin, A. [IRSN Forschungszentrum Karlsruhe GmbH, D-76021 Karlsruhe, (Germany); Godin-Jacqmin, L. [CEA Cadarache, DEN STRI LMA, F-13115 St Paul Les Durance (France); Tran, C. T.; Ma, W. M. [KTH, AlbaNova Univ Ctr, S-10691 Stockholm (Sweden); Chudanov, V. [Nucl Safety Inst, Moscow 113191 (Russian Federation)

    2010-07-01

    The development of a corium pool in the lower head and its behaviour is still a critical issue. This concerns, in general, the understanding of a severe accident with core melting, its course, major critical phases and timing, and the influence of these processes on the accident progression as well as, in particular, the evaluation of in-vessel melt retention by external vessel flooding as an accident mitigation strategy. Previous studies were especially related to the in-vessel retention question and often just concentrated on the quasi-steady state behaviour of a large molten pool in the lower head, considered as a bounding configuration. However, non-feasibility of the in-vessel retention concept for high power density reactors and uncertainties e. g. due to layering effects even for low or medium power reactors, turns this to be insufficient. Rather, it is essential to consider the whole evolution of the accident, including e. g. formation and growth of the in-core melt pool, characteristics of corium arrival in the lower head, and molten pool behaviour after the debris re-melting. These phenomena have a strong impact on a potential termination of a severe accident. The general objective of the LIVE program at FZK is to study these phenomena resulting from core melting experimentally in large-scale 3D geometry and in supporting separate-effects tests, with emphasis on the transient behaviour. Up to now, several tests on molten pool behaviour have been performed within the LIVE experimental program with water and with non-eutectic melts (KNO{sub 3}-NaNO{sub 3}) as simulant fluids. The results of these experiments, performed in nearly adiabatic and in isothermal conditions, allow a direct comparison with findings obtained earlier in other experimental programs (SIMECO, ACOPO, BALI, etc. ) and will be used for the assessment of the correlations derived for the molten pool behaviour. Complementary to other international programs with real corium melts, the results

  17. Parametric soil water retention models: a critical evaluation of expressions for the full moisture range

    Science.gov (United States)

    Madi, Raneem; Huibert de Rooij, Gerrit; Mielenz, Henrike; Mai, Juliane

    2018-02-01

    Few parametric expressions for the soil water retention curve are suitable for dry conditions. Furthermore, expressions for the soil hydraulic conductivity curves associated with parametric retention functions can behave unrealistically near saturation. We developed a general criterion for water retention parameterizations that ensures physically plausible conductivity curves. Only 3 of the 18 tested parameterizations met this criterion without restrictions on the parameters of a popular conductivity curve parameterization. A fourth required one parameter to be fixed. We estimated parameters by shuffled complex evolution (SCE) with the objective function tailored to various observation methods used to obtain retention curve data. We fitted the four parameterizations with physically plausible conductivities as well as the most widely used parameterization. The performance of the resulting 12 combinations of retention and conductivity curves was assessed in a numerical study with 751 days of semiarid atmospheric forcing applied to unvegetated, uniform, 1 m freely draining columns for four textures. Choosing different parameterizations had a minor effect on evaporation, but cumulative bottom fluxes varied by up to an order of magnitude between them. This highlights the need for a careful selection of the soil hydraulic parameterization that ideally does not only rely on goodness of fit to static soil water retention data but also on hydraulic conductivity measurements. Parameter fits for 21 soils showed that extrapolations into the dry range of the retention curve often became physically more realistic when the parameterization had a logarithmic dry branch, particularly in fine-textured soils where high residual water contents would otherwise be fitted.

  18. Employee retention and motivation as correlates of organization ...

    African Journals Online (AJOL)

    This study examined the correlation between employee retention, motivation and organization performance among bank employees in Lagos, Nigeria. The study adopted an expo facto research design. Three hypotheses were generated and tested in the study. Respondent were two hundred and fifty (250) bankers that ...

  19. Influence of cement film thickness on the retention of implant-retained crowns.

    Science.gov (United States)

    Mehl, Christian; Harder, Sönke; Steiner, Martin; Vollrath, Oliver; Kern, Matthias

    2013-12-01

    The main goal of this study was to establish a new, high precision procedure to evaluate the influence of cement film thickness on the retention of cemented implant-retained crowns. Ninety-six tapered titanium abutments (6° taper, 4.3 mm diameter, Camlog) were shortened to 4 mm. Computer-aided design was used to design the crowns, and selective laser sintering, using a cobalt-chromium alloy, was used to produce the crowns. This method used a focused high-energy laser beam to fuse a localized region of metal powder to build up the crowns gradually. Before cementing, preset cement film thicknesses of 15, 50, 80, or 110 ÎŒm were established. Glass ionomer, polycarboxylate, or resin cements were used for cementation. After 3 days storage in demineralized water, the retention of the crowns was measured in tension using a universal testing machine. The cement film thicknesses could be achieved with a high level of precision. Interactions between the factors cement and cement film thickness could be found (p ≀ 0.001). For all cements, crown retention decreased significantly between a cement film thickness of 15 and 50 ÎŒm (p ≀ 0.001). At 15 ÎŒm cement film thickness, the resin cement was the most retentive cement, followed by the polycarboxylate and then the glass ionomer cement (p ≀ 0.05). The results suggest that cement film thickness has an influence on the retentive strength of cemented implant-retained crowns. © 2013 by the American College of Prosthodontists.

  20. Comparative Evaluation of Retentive Properties of Two Compatible Ball Attachments in Mandibular Implant-Retained Overdentures: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Maryam Memarian

    2018-02-01

    Full Text Available Objectives: The retentive properties of implant-retained overdentures (IRO may be influenced by the type of attachments. The aim of this research was to compare the retention of two dental implant systems with compatible ball attachments, namely StraumannŸ system (SS and Rhein83 SRL system (RS after fatigue testing.Materials and Methods: Two laboratory models consisting of two parallel StraumannŸ fixtures at a distance of 22 mm were prepared. Five pairs of each systems' ball attachments were examined (n=5. The samples were soaked in artificial saliva. The retention strength values (RSV were recorded before the fatigue test and after 1100, 2200, 3300, 4400, and 5500 insertion and removal cycles at a speed of 51 mm/minute with a 50-N load cell in a universal testing machine. The data were analyzed by repeated measures analysis of variance (ANOVA followed by independent sample t-test with Bonferroni corrections.Results: There was a decrease in the RSV in both systems after 5500 cycles of insertion and removal. There was a significant statistical difference between the RSV of the normal Sphero Block of the RS (17.52±0.68 N and that of the Spare Lamella retention inserts of the SS (19.72±0.74 N, P=0.001.Conclusions: Although the RSVs of the RS and SS were almost similar before the fatigue test, as the number of insertion and removal cycles increased, the RSV decreased more significantly in the RS compared to the SS.

  1. Influence of dietary calcium (Ca) and phosphorus (P) on phosphorus retention in chickens

    International Nuclear Information System (INIS)

    Scheideler, S.E.; Sell, J.L.

    1986-01-01

    Experiment 1 was a 3 x 3 factorial arrangement with 3 levels of dietary Ca (3.0, 3.5, and 4.0%) and 3 P feeding programs fed to laying hens for 336 days. The P programs tested were: .64% P fed continuously for 48 weeks; .64, .54, and .44% P; and .56, .49, and .39% P fed when hens were 24 to 36, 36 to 52, and 52 to 72 weeks of age, respectively. In addition to production traits, measurements of P retention were made at 34, 42, 50, 62, and 72 weeks of age. None of the production traits measured showed any dietary effects. Dietary Ca affected P retention at 50, 62, and 72 weeks of age. None of the production traits measured showed any dietary effects. Dietary Ca affected P retention at 50, 62, and 72 weeks of age. Average P retention for the experiment was 104, 148, and 178 mg/day in hens fed 3.0, 3.5, and 4.0% Ca. Dietary P affected P retention at 42 and 72 weeks, with P retention being greater in hens fed .64% P. Ca x P interactions were measured at 42, 62, and 72 weeks of age. Experiment 2 involved 2 levels of dietary Ca (.8 and 1.2%) fed to one-week-old broiler chicks for 8 days during which time 50 uCi 33 P/chick were administered. Serum, femurs, and excreta were collected 48 hours following 33 P dosing. Serum inorganic P and excreted 33 P activity were greater in chicks fed .8% Ca; whereas femur 33 P activity was greater when chicks received the 1.2% Ca diet. These data indicate increased P retention and greater bone deposition of P in chicks fed 1.2% dietary Ca. These results support those of Experiment 1 in which P retention of hens increased as dietary Ca increased

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

    Science.gov (United States)

    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. Automatic grading of appearance retention of carpets using intensity and range images

    Science.gov (United States)

    Orjuela Vargas, Sergio Alejandro; Ortiz-Jaramillo, Benhur; Vansteenkiste, Ewout; Rooms, Filip; De Meulemeester, Simon; de Keyser, Robain; Van Langenhove, Lieva; Philips, Wilfried

    2012-04-01

    Textiles are mainly used for decoration and protection. In both cases, their original appearance and its retention are important factors for customers. Therefore, evaluation of appearance parameters are critical for quality assurance purposes, during and after manufacturing, to determine the lifetime and/or beauty of textile products. In particular, appearance retention of textile products is commonly certified with grades, which are currently assigned by human experts. However, manufacturers would prefer a more objective system. We present an objective system for grading appearance retention, particularly, for textile floor coverings. Changes in appearance are quantified by using linear regression models on texture features extracted from intensity and range images. Range images are obtained by our own laser scanner, reconstructing the carpet surface using two methods that have been previously presented. We extract texture features using a variant of the local binary pattern technique based on detecting those patterns whose frequencies are related to the appearance retention grades. We test models for eight types of carpets. Results show that the proposed approach describes the degree of wear with a precision within the range allowed to human inspectors by international standards. The methodology followed in this experiment has been designed to be general for evaluating global deviation of texture in other types of textiles, as well as other surface materials.

  4. Manager impact on retention of hospital staff: Part 2.

    Science.gov (United States)

    Taunton, R L; Krampitz, S D; Woods, C Q

    1989-04-01

    This is the second article in a two-part series based on a study of the impact of middle managers on retention of 71 hospital professionals. Research design, methods, and descriptive results were presented in Part 1 (March 1989). In Part 2, the impact of managers' motivation to manage, power, influence, and leadership style on retention is detailed. Recommendations for improving retention include interventions to increase employee job satisfaction and intent to stay, and to improve managers' performance and leadership.

  5. Urinary Retention Associated with Stroke.

    Science.gov (United States)

    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.

  6. Blood Pressure Directed Booster Trainings Improve Intensive Care Unit Provider Retention of Excellent Cardiopulmonary Resuscitation Skills.

    Science.gov (United States)

    Wolfe, Heather; Maltese, Matthew R; Niles, Dana E; Fischman, Elizabeth; Legkobitova, Veronika; Leffelman, Jessica; Berg, Robert A; Nadkarni, Vinay M; Sutton, Robert M

    2015-11-01

    Brief, intermittent cardiopulmonary resuscitation (CPR) training sessions, "Booster Trainings," improve CPR skill acquisition and short-term retention. The objective of this study was to incorporate arterial blood pressure (ABP) tracings into Booster Trainings to improve CPR skill retention. We hypothesized that ABP-directed CPR "Booster Trainings" would improve intensive care unit (ICU) provider 3-month retention of excellent CPR skills without need for interval retraining. A CPR manikin creating a realistic relationship between chest compression depth and ABP was used for training/testing. Thirty-six ICU providers were randomized to brief, bedside ABP-directed CPR manikin skill retrainings: (1) Booster Plus (ABP visible during training and testing) versus (2) Booster Alone (ABP visible only during training, not testing) versus (3) control (testing, no intervention). Subjects completed skill tests pretraining (baseline), immediately after training (acquisition), and then retention was assessed at 12 hours, 3 and 6 months. The primary outcome was retention of excellent CPR skills at 3 months. Excellent CPR was defined as systolic blood pressure of 100 mm Hg or higher and compression rate 100 to 120 per minute. Overall, 14 of 24 (58%) participants acquired excellent CPR skills after their initial training (Booster Plus 75% vs 50% Booster Alone, P = 0.21). Adjusted for age, ABP-trained providers were 5.2× more likely to perform excellent CPR after the initial training (95% confidence interval [95% CI], 1.3-21.2; P = 0.02), and to retain these skills at 12 hours (adjusted odds ratio, 4.4; 95% CI, 1.3-14.9; P = 0.018) and 3 months (adjusted odds ratio, 4.1; 95% CI, 1.2-13.9; P = 0.023) when compared to baseline performance. The ABP-directed CPR booster trainings improved ICU provider 3-month retention of excellent CPR skills without the need for interval retraining.

  7. Ex-vessel boiling experiments: laboratory- and reactor-scale testing of the flooded cavity concept for in-vessel core retention. Pt. II. Reactor-scale boiling experiments of the flooded cavity concept for in-vessel core retention

    International Nuclear Information System (INIS)

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

    1997-01-01

    For pt.I see ibid., p.77-88 (1997). This paper summarizes the results of a reactor-scale ex-vessel boiling experiment for assessing the flooded cavity design of the heavy water new production reactor. The simulated reactor vessel has a cylindrical diameter of 3.7 m and a torispherical bottom head. Boiling outside the reactor vessel was found to be subcooled nucleate boiling. The subcooling mainly results from the gravity head, which in turn results from flooding the side of the reactor 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. The results show that, under prototypic heat load and heat flux distributions, the flooded cavity will be effective for in-vessel core retention in the heavy water new production reactor. The results also demonstrate that the heat dissipation requirement for in-vessel core retention, for the central region of the lower head of an AP-600 advanced light water reactor, can be met with the flooded cavity design. (orig.)

  8. Implicit memory. Retention without remembering.

    Science.gov (United States)

    Roediger, H L

    1990-09-01

    Explicit measures of human memory, such as recall or recognition, reflect conscious recollection of the past. Implicit tests of retention measure transfer (or priming) from past experience on tasks that do not require conscious recollection of recent experiences for their performance. The article reviews research on the relation between explicit and implicit memory. The evidence points to substantial differences between standard explicit and implicit tests, because many variables create dissociations between these tests. For example, although pictures are remembered better than words on explicit tests, words produce more priming than do pictures on several implicit tests. These dissociations may implicate different memory systems that subserve distinct memorial functions, but the present argument is that many dissociations can be understood by appealing to general principles that apply to both explicit and implicit tests. Phenomena studied under the rubric of implicit memory may have important implications in many other fields, including social cognition, problem solving, and cognitive development.

  9. The effect of anchovy substrate application to fluor retention rate on Sprague Dawley rat tooth email (in vivo)

    Science.gov (United States)

    Zabrina, S.; Puspitawati, R.; Gunawan, H. A.

    2017-08-01

    Usage of anchovies (Stolephorus insularis), which contain a high fluoride concentration in a CaF2 compound, needs to be examined as a topical fluoridative agent. Aim: To study the effects of an anchovy substrate application, either by chewing or smearing, in increasing fluoride retention of enamel. Fourteen Sprague Dawley rats were divided into five groups: baseline, experimental (feeding and smearing), and negative controls. After 15 days, lower incisor teeth were extracted and fluoride retention on the enamel surface was measured using EDX. Data were analyzed by the independent samples t-test, the Mann-Whitney U test, and the Kruskal-Wallis test. There was a significant increase in fluoride retention on enamel from the experimental groups compared to the negative control group (p < 0.05). Fluoride retention levels of the experimental feeding group (6.823%) were slightly higher than those of the experimental smearing group (6.783%), though the difference was not statistically significant (p < 0.05). Anchovy substrate application, either by chewing or smearing, increases fluoride retention on tooth enamel.

  10. Retention behaviour of some estradiol derivatives on alumina in normal phase chromatography

    Directory of Open Access Journals (Sweden)

    MARIJANA M. ACANSKI

    2003-03-01

    Full Text Available The retention constants of variously substituted estradiol derivatives were measured as a function of the composition of various binary mobile phases in order to study the relationship between chemical structure and retention behaviour in TLC on alumina. The slopes and intercepts of the linear relationships between the retention constant RM and the logarithm of the volume fraction of the polar mobile phase component were calculated and are discussed in relation to the characteristics of the solute and mobile phase. The RFvalues and relative retention DRM of the compounds depend largely on the retention behaviour of their substituents. The results obtained in this investigation are compared with the results of the same derivatives obtained in previous investigations on silica gel.

  11. Fission product retention in TRISO coated UO2 particle fuels subjected to HTR simulated core heating tests

    International Nuclear Information System (INIS)

    Baldwin, C.A.; Kania, M.J.

    1991-01-01

    Results of the examination and analysis of 25,730 individual microspheres from spherical fuel elements HFR-K3/1 and HFR-K3/3 are reported. The parent spheres were irradiated in excess of end-of-life exposure and subsequently subjected to simulated core heating tests in a special high-temperature furnace at Forschungszentrum, Juelich, GmbH (KFA). Following the heating tests, the spheres were electrolytically deconsolidated to obtain unbounded fuel particles for Irradiated Microsphere Gamma Analyzer (IMGA) analysis. For sphere HFR-K3/1, which was heated for 500 h at 1600 deg. C, only four particles were identified as having released fission products. The remaining particles from the sphere showed no statistical evidence of fission product release. Scanning Electron Microscopy (SEM) examination showed that three of the defect particles had large sections of the TRISO coating missing, while the fourth appeared normal. For sphere HFR-K3/3, which was heated for 100 h at 1800 deg. C, the IMGA data revealed that fission product release (cesium) from individual particles was significant and that there was large particle-to-particle variation in retention capabilities. Individual particle release (cesium) averaged ten times the KFA-measured integral spherical fuel element release value. In addition, the bimodal distribution of the individual particle data indicated that two distinct modes of failure at fuel temperatures of 1800 deg. C and above may exist. (author). 6 refs, 6 figs, 4 tabs

  12. Fission product retention in TRISCO coated UO2 particle fuels subjected to HTR simulated core heating tests

    International Nuclear Information System (INIS)

    Baldwin, C.A.; Kania, M.J.

    1990-11-01

    Results of the examination and analysis of 25,730 individual microspheres from spherical fuel elements HFR-K3/1 and HFR-K3/3 are reported. The parent spheres were irradiated in excess of end-of-life exposure and subsequently subjected to simulated core heating tests in a special high-temperature furnace at Forschungszentrum, Juelich, GmbH (KFA). Following the heating tests, the spheres were electrolytically deconsolidated to obtain unbonded fuel particles for Irradiated Microsphere Gamma Analyzer (IMGA) analysis. For sphere HFR-K3/1, which was heated for 500 h at 1600 degree C, only four particles were identified as having released fission products. The remaining particles from the sphere showed no statistical evidence of fission product release. Scanning Electron Microscopy (SEM) examination showed that three of the defect particles had large sections of the TRISO coating missing, while the fourth appeared normal. For sphere HFR-K3/3, which was heated for 100 h at 1800 degree C, the IMGA data revealed that fission product release (cesium) from individual particles was significant and that there was large particle-to-particle variation in retention capabilities. Individual particle release (cesium) averaged ten times the KFA-measured integral spherical fuel element release value. In addition, the bimodal distribution of the individual particle data indicated that two distinct modes of failure at fuel temperatures of 1800 degree C and above may exist. 6 refs., 6 figs., 4 tabs

  13. Military Retention. A Comparative Outlook

    Directory of Open Access Journals (Sweden)

    Vasile Sminchise

    2016-06-01

    Full Text Available One of the main goals for human resources management structures and for armed forces leaders is to maintain all necessary personnel, both qualitatively and quantitatively for operational needs or for full required capabilities. The retention of military personnel is essential to keep morale and unit readiness and to reduce the costs for recruiting, training, replacement of manpower. Retention rates depend not only on money or other social measures. The goal for retention is to keep in use the most valuable resource that belongs to an organization: the human beings and their knowledge. The aim pf this paper is to provide a comparative analysis of retention measures in various countries based on Research and Technology Organisation report released in 2007 and, thus, provide more examples of retention measures as far as the Romanian military system is concerned.

  14. Safeguards Workforce Repatriation, Retention and Utilization

    Energy Technology Data Exchange (ETDEWEB)

    Gallucci, Nicholas [Brookhaven National Lab. (BNL), Upton, NY (United States); Poe, Sarah [Brookhaven National Lab. (BNL), Upton, NY (United States)

    2015-10-01

    Brookhaven National Laboratory was tasked by NA-241 to assess the transition of former IAEA employees back to the United States, investigating the rate of retention and overall smoothness of the repatriation process among returning safeguards professionals. Upon conducting several phone interviews, study authors found that the repatriation process went smoothly for the vast majority and that workforce retention was high. However, several respondents expressed irritation over the minimal extent to which their safeguards expertise had been leveraged in their current positions. This sentiment was pervasive enough to prompt a follow-on study focusing on questions relating to the utilization rather than the retention of safeguards professionals. A second, web-based survey was conducted, soliciting responses from a larger sample pool. Results suggest that the safeguards workforce may be oversaturated, and that young professionals returning to the United States from Agency positions may soon encounter difficulties finding jobs in the field.

  15. Pre-stimulus BOLD-network activation modulates EEG spectral activity during working memory retention

    Directory of Open Access Journals (Sweden)

    Mara eKottlow

    2015-05-01

    Full Text Available Working memory (WM processes depend on our momentary mental state and therefore exhibit considerable fluctuations. Here, we investigate the interplay of task-preparatory and task-related brain activity as represented by pre-stimulus BOLD-fluctuations and spectral EEG from the retention periods of a visual WM task. Visual WM is used to maintain sensory information in the brain enabling the performance of cognitive operations and is associated with mental health.We tested 22 subjects simultaneously with EEG and fMRI while performing a visuo-verbal Sternberg task with two different loads, allowing for the temporal separation of preparation, encoding, retention and retrieval periods.Four temporally coherent networks - the default mode network (DMN, the dorsal attention, the right and the left WM network - were extracted from the continuous BOLD data by means of a group ICA. Subsequently, the modulatory effect of these networks’ pre-stimulus activation upon retention-related EEG activity in the theta, alpha and beta frequencies was analyzed. The obtained results are informative in the context of state-dependent information processing.We were able to replicate two well-known load-dependent effects: the frontal-midline theta increase during the task and the decrease of pre-stimulus DMN activity. As our main finding, these two measures seem to depend on each other as the significant negative correlations at frontal-midline channels suggested. Thus, suppressed pre-stimulus DMN levels facilitated later task related frontal midline theta increases. In general, based on previous findings that neuronal coupling in different frequency bands may underlie distinct functions in WM retention, our results suggest that processes reflected by spectral oscillations during retention seem not only to be online synchronized with activity in different attention-related networks but are also modulated by activity in these networks during preparation intervals.

  16. Evaluation of {sup 131}I retention in several adsorbers

    Energy Technology Data Exchange (ETDEWEB)

    Catanoso, Marcela F.; Osso Junior, Joao Alberto, E-mail: marcela.forli@gmail.co, E-mail: jaosso@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil). Diretoria de Radiofarmacia

    2011-07-01

    Several iodine radioisotopes are used in nuclear medicine for treatment and diagnostic purposes. The radioisotope {sup 131}I is used both in diagnosis and therapy due to its physical characteristics of decay by {beta}{sup -} and its {gamma}-ray emissions suitable for diagnosis. It is routinely produced at IPEN through the irradiation of TeO{sub 2} targets in the IEA-R1m nuclear reactor. After the irradiation, the {sup 131}I is separated by dry distillation, where the targets are put in an oven, heated at 760 deg C for 2 hours and the {sup 131}I, volatile, is carried by an O{sub 2} gas stream. The aim of this work was to evaluate the retention and elution of {sup 131}I samples produced at IPEN in several adsorbers as part of a project aiming the purification of these radioisotopes, allowing the labeling of biomolecules. Samples of {sup 131}I were used for retention and elution studies with the following adsorbers: commercial cartridges, anionic resin columns and cationic resin column. The results showed that Ag cartridges and anionic resins Dowex 1X8, Dowex 3 and IRA 400 had a great iodine retention but no elution after using specific eluents. The QMA light, acid alumina, neutral alumina and cationic resin Dowex 50WX4 showed high retention and elution and QMA plus and cationic resin Dowex 50WX8 and Dowex 50WX12 had a good retention but lower elution. Regarding to the better retention and elution, Ag cartridges and resins showed a higher percentage of iodine retention but lower elution yield and QMA light, acid and neutral alumina cartridges showed better results. (author)

  17. Retention of knowledge and skills in pediatric basic life support amongst pediatricians.

    Science.gov (United States)

    Binkhorst, Mathijs; Coopmans, Michelle; Draaisma, Jos M T; Bot, Petra; Hogeveen, Marije

    2018-05-07

    Retention of resuscitation skills is usually assessed at a predefined moment, which enables participants to prepare themselves, possibly introducing bias. In this multicenter study, we evaluated the retention of knowledge and skills in pediatric basic life support (PBLS) amongst 58 pediatricians and pediatric residents with an unannounced examination. Practical PBLS skills were assessed with a validated scoring instrument, theoretical knowledge with a 10-item multiple-choice test (MCQ). Participants self-assessed their PBLS capabilities using five-point Likert scales. Background data were collected with a questionnaire. Of our participants, 21% passed the practical PBLS exam: 29% failed on compressions/ventilations, 31% on other parts of the algorithm, 19% on both. Sixty-nine percent passed the theoretical test. Participants who more recently completed a PBLS course performed significantly better on the MCQ (p = 0.03). This association was less clear-cut for performance on the practical exam (p = 0.11). Older, attending pediatricians with more years of experience in pediatrics performed less well than their younger colleagues (p basic life support (PBLS) in daily practice. Poor retention of skills supposedly accounts for this incompetence. Without regular exposure, resuscitation skills usually deteriorate within 3 to 6 months after training. ‱ Examination of resuscitation skills usually takes place after training. Also, in most studies evaluating retention of skills, participants are tested at a predefined moment. Inasmuch as participants are able to prepare themselves, these assessments do not reflect the ad hoc resuscitation capabilities of pediatricians and residents. What is New: ‱ In this study, pediatricians and pediatric residents had to complete an unannounced PBLS exam at variable time intervals from last certification. Retention of PBLS skills was rather poor (pass rate 21%). ‱ The PBLS skills of older, attending pediatricians with many

  18. Job embeddedness and nurse retention.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  20. Chemical composition of the essential oils of Citrus sinensis cv. valencia and a quantitative structure-retention relationship study for the prediction of retention indices by multiple linear regression

    Directory of Open Access Journals (Sweden)

    Larijani Kambiz

    2011-01-01

    Full Text Available The chemical composition of the volatile fraction obtained by head-space solid phase microextraction (HS-SPME, single drop microextraction (SDME and the essential oil obtained by cold-press from the peels of C. sinensis cv. valencia were analyzed employing gas chromatography-flame ionization detector (GC-FID and gas chromatography-mass spectrometry (GC-MS. The main components were limonene (61.34 %, 68.27 %, 90.50 %, myrcene (17.55 %, 12.35 %, 2.50 %, sabinene (6.50 %, 7.62 %, 0.5 % and α-pinene (0 %, 6.65 %, 1.4 % respectively obtained by HS-SPME, SDME and cold-press. Then a quantitative structure-retention relationship (QSRR study for the prediction of retention indices (RI of the compounds was developed by application of structural descriptors and the multiple linear regression (MLR method. Principal components analysis was used to select the training set. A simple model with low standard errors and high correlation coefficients was obtained. The results illustrated that linear techniques such as MLR combined with a successful variable selection procedure are capable of generating an efficient QSRR model for prediction of the retention indices of different compounds. This model, with high statistical significance (R2 train = 0.983, R2 test = 0.970, Q2 LOO = 0.962, Q2 LGO = 0.936, REP(% = 3.00, could be used adequately for the prediction and description of the retention indices of the volatile compounds.

  1. Retention of ionisable compounds on high-performance liquid chromatography XVI. Estimation of retention with acetonitrile/water mobile phases from aqueous buffer pH and analyte pKa.

    Science.gov (United States)

    Subirats, Xavier; Bosch, Elisabeth; Rosés, Martí

    2006-07-21

    In agreement with our previous studies and those of other authors, it is shown that much better fits of retention time as a function of pH are obtained for acid-base analytes when pH is measured in the mobile phase, than when pH is measured in the aqueous buffer when buffers of different nature are used. However, in some instances it may be more practical to measure the pH in the aqueous buffer before addition of the organic modifier. Thus, an open methodology is presented that allows prediction of chromatographic retention of acid-base analytes from the pH measured in the aqueous buffer. The model presented estimates the pH of the buffer and the pKa of the analyte in a particular acetonitrile/water mobile phase from the pH and pKa values in water. The retention of the analyte can be easily estimated, at a buffer pH close to the solute pKa, from these values and from the retentions of the pure acidic and basic forms of the analyte. Since in many instances, the analyte pKa values in water are not known, the methodology has been also tested by using Internet software, at reach of many chemists, which calculates analyte pKa values from chemical structure. The approach is successfully tested for some pharmaceutical drugs.

  2. Adherence of pregnant women to Nordic dietary guidelines in relation to postpartum weight retention: results from the Norwegian Mother and Child Cohort Study.

    Science.gov (United States)

    von Ruesten, Anne; BrantsĂŠter, Anne Lise; Haugen, Margaretha; Meltzer, Helle Margrete; Mehlig, Kirsten; Winkvist, Anna; Lissner, Lauren

    2014-01-24

    Pregnancy is a major life event for women and often connected with changes in diet and lifestyle and natural gestational weight gain. However, excessive weight gain during pregnancy may lead to postpartum weight retention and add to the burden of increasing obesity prevalence. Therefore, it is of interest to examine whether adherence to nutrient recommendations or food-based guidelines is associated with postpartum weight retention 6 months after birth. This analysis is based on data from the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health. Diet during the first 4-5 months of pregnancy was assessed by a food-frequency questionnaire and maternal weight before pregnancy as well as in the postpartum period was assessed by questionnaires. Two Healthy Eating Index (HEI) scores were applied to measure compliance with either the official Norwegian food-based guidelines (HEI-NFG) or the Nordic Nutrition Recommendations (HEI-NNR) during pregnancy. The considered outcome, i.e. weight retention 6 months after birth, was modelled in two ways: continuously (in kg) and categorically (risk of substantial postpartum weight retention, i.e. ≄ 5% gain to pre-pregnancy weight). Associations between the HEI-NFG and HEI-NNR score with postpartum weight retention on the continuous scale were estimated by linear regression models. Relationships of both HEI scores with the categorical outcome variable were evaluated using logistic regression. In the continuous model without adjustment for gestational weight gain (GWG), the HEI-NFG score but not the HEI-NNR score was inversely related to postpartum weight retention. However, after additional adjustment for GWG as potential intermediate the HEI-NFG score was marginally inversely and the HEI-NNR score was inversely associated with postpartum weight retention. In the categorical model, both HEI scores were inversely related with risk of substantial postpartum weight retention

  3. Coherent oscillatory networks supporting short-term memory retention.

    Science.gov (United States)

    Payne, Lisa; Kounios, John

    2009-01-09

    Accumulating evidence suggests that top-down processes, reflected by frontal-midline theta-band (4-8 Hz) electroencephalogram (EEG) oscillations, strengthen the activation of a memory set during short-term memory (STM) retention. In addition, the amplitude of posterior alpha-band (8-13 Hz) oscillations during STM retention is thought to reflect a mechanism that protects fragile STM activations from interference by gating bottom-up sensory inputs. The present study addressed two important questions about these phenomena. First, why have previous studies not consistently found memory set-size effects on frontal-midline theta? Second, how does posterior alpha participate in STM retention? To answer these questions, large-scale network connectivity during STM retention was examined by computing EEG wavelet coherence during the retention period of a modified Sternberg task using visually-presented letters as stimuli. The results showed (a) increasing theta-band coherence between frontal-midline and left temporal-parietal sites with increasing memory load, and (b) increasing alpha-band coherence between midline parietal and left temporal/parietal sites with increasing memory load. These findings support the view that theta-band coherence, rather than amplitude, is the key factor in selective top-down strengthening of the memory set and demonstrate that posterior alpha-band oscillations associated with sensory gating are involved in STM retention by participating in the STM network.

  4. Evaluation of the retentive means, opacifiers and veneering materials for veneered crowns using 137 Cs

    International Nuclear Information System (INIS)

    Nour, A.M.; El-Sadeek; M.E.; Ramadan, F.A.; Eskander, M.

    1991-01-01

    The purpose of this investigation is to evaluate the best plastic veneering material, which affords initial sealing and adaptation to the metal backing. Cs chloride is used for this purpose. The effect of different retentive means, namely, under cuts, wire loops, stainless steel grills, and acrylic beads, as well as the effect of different opaquers were studied. The influence of time factor and changing temperature was considered as well. The results obtained showed the following: 1- A quantitative method for the evaluation of micro leakage is essential parallel to the semiquantitative one. 2- The tested opaquer exhibits a better sealing ability. 3- The leakage increases significantly by temperature cycling, and by time duration with all the veneering materials tested. Composite is the least leak-sensitive material to changes in temperature. 4- Beads offered the best means of retention, to obtain the best sealing qualities.1 tab., 2 fig

  5. Urinary retention in women

    African Journals Online (AJOL)

    Urinary retention in women. Urinary retention in women is often transient and of no known cause. ... stones, constipation, urethral cancer, uterine fibroids ... present with abnormal bladder function secondary to ... (CT), magnetic resonance imaging (MRI) or myelography ... full blood count, urea, electrolytes and creatinine can ...

  6. The Role of Multichannel Marketing in Customer Retention and Loyalty: Study in Emerald Bank Customer in Indonesia

    Directory of Open Access Journals (Sweden)

    Ambarwati Ambarwati

    2015-09-01

    Full Text Available Attention on the relationship between customer retention, customer loyalty, and customer satisfaction that serves as "seed" of customer loyalty highlight the important factors for multichannel management. With the growing trends of people in investing their money in bank for securities need to be responded by the marketing department to create better marketing strategies. The purpose of this study is to examine and explain the effect of a multichannel bank on emerald customers retention   in one of the largest SOE bank in Indonesia, in the city of Surabaya, BNI (Bank Negara Indonesia toward customer  satisfaction, loyalty and customer  retention. This study develops the theory  of  mix marketing by using multichannel  as one of the elements that can increase customer retention   using satisfaction mediation and customer loyalty. Mechanical determination of sample units in this study is a  purposive sampling, of 89 respondents. Generalized Structured Component Analysis (GSCA was applied to test the hypotheses. The results of this study indicate that direct multichannel not  significantly effect the customer retention. Customer satisfaction can not be a perfect mediation  and the customer loyalty can be a perfect mediation in the relationship between multichannel and customer retention. This study contributes to the banking industry in applying the concept of the mix marketing.

  7. Sodalite as a vehicle to increase Re retention in waste glass simulant during vitrification

    Energy Technology Data Exchange (ETDEWEB)

    Luksic, Steven A., E-mail: steven.luksic@pnnl.gov; Riley, Brian J.; Parker, Kent E.; Hrma, Pavel

    2016-10-15

    Technetium (Tc) retention during Hanford waste vitrification can be increased if the volatility can be controlled. Incorporating Tc into a thermally stable mineral phase, such as sodalite, is one way to achieve increased retention. Here, rhenium (Re)-bearing sodalite was tested as a vehicle to transport perrhenate (ReO{sub 4}{sup −}), a nonradioactive surrogate for pertechnetate (TcO{sub 4}{sup −}), into high-level (HLW) and low-activity waste (LAW) glass simulants. After melting HLW and LAW simulant feeds, the retention of Re in the glass was measured and compared with the Re retention in glass prepared from a feed containing Re{sub 2}O{sub 7}. Phase analysis of sodalite in both these glasses across a profile of temperatures describes the durability of Re-sodalite during the feed-to-glass transition. The use of Re sodalite improved the Re retention by 21% for HLW glass and 85% for LAW glass, demonstrating the potential improvement in Tc-retention if TcO{sub 4}{sup −} were to be encapsulated in a Tc-sodalite prior to vitrification. - Highlights: ‱ Re retention is improved by incorporation into sodalite structure. ‱ LAW-type glass shows lower retention but larger improvement with Re-sodalite. ‱ Sodalite is stable to higher temperatures in high-alumina glass melts.

  8. The Effect of Perceptual Learning on L2 Vocabulary Learning and Retention

    OpenAIRE

    BEDÄ°R, GĂŒlay; BEKTAƞ BEDÄ°R, Sevgi

    2018-01-01

    It is thought that learning styles have an effecton learning foreign language. This study aims to determine effects ofperceptual learning styles on L2 vocabulary learning and retention. Learningstyle preferences were assessed in the current study through the section ofCohen et al.’s Learning Style Survey (LSS) corresponding to the perceptualmodalities and achievement tests developed by the researcher was used to assessvocabulary learning and retention. And an open-ended question is tried toan...

  9. An in vitro investigation into retention strength and fatigue resistance of various designs of tooth/implant supported overdentures.

    Science.gov (United States)

    Fatalla, Abdalbseet A; Song, Ke; Du, Tianfeng; Cao, Yingguang

    2012-02-01

    and 2880 insertion and removal cycles. During the tensile test a cross-head speed of 10 mm/min was applied. Values of absolute force (AF) and relative force (RF) were statistically analyzed by two-way ANOVA and multiple comparison Tukey's tests between groups and cycles periods. The results of fatigue tests showed a 50% reduction in retention force in the subgroups with flexible attachments. A triangular design of overdenture support foundations with O-Ring attachments revealed the lowest value of AF and a relatively high reduction in RF. The four overdenture support designs with flexible acrylic attachments improved the retention force and reduced the fatigue retention. Furthermore, the results of the investigation demonstrate that flexible acrylic attachments for both teeth and implant-supported overdentures offer a wide range of retention forces.

  10. A simple, fast, and accurate thermodynamic-based approach for transfer and prediction of gas chromatography retention times between columns and instruments Part III: Retention time prediction on target column.

    Science.gov (United States)

    Hou, Siyuan; Stevenson, Keisean A J M; Harynuk, James J

    2018-03-27

    This is the third part of a three-part series of papers. In Part I, we presented a method for determining the actual effective geometry of a reference column as well as the thermodynamic-based parameters of a set of probe compounds in an in-house mixture. Part II introduced an approach for estimating the actual effective geometry of a target column by collecting retention data of the same mixture of probe compounds on the target column and using their thermodynamic parameters, acquired on the reference column, as a bridge between both systems. Part III, presented here, demonstrates the retention time transfer and prediction from the reference column to the target column using experimental data for a separate mixture of compounds. To predict the retention time of a new compound, we first estimate its thermodynamic-based parameters on the reference column (using geometric parameters determined previously). The compound's retention time on a second column (of previously determined geometry) is then predicted. The models and the associated optimization algorithms were tested using simulated and experimental data. The accuracy of predicted retention times shows that the proposed approach is simple, fast, and accurate for retention time transfer and prediction between gas chromatography columns. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

    Science.gov (United States)

    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 tested. However, only the TP-duo showed a significant reduction in time in removal forces for both protrusion positions (P 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.

  12. Fuel-coolant interaction visualization test for in-vessel corium retention external reactor vessel cooling (IVR-ERVC) condition

    Energy Technology Data Exchange (ETDEWEB)

    Na, Young Su; Hong, Seong Ho; Song, Jin Ho; Hong, Seong Wan [Severe Accident and PHWR Safety Research Division, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-12-15

    A visualization test of the fuel-coolant interaction in the Test for Real cOrium Interaction with water (TROI) test facility was carried out. To experimentally simulate the In-Vessel corium Retention (IVR)- External Reactor Vessel Cooling (ERVC) conditions, prototypic corium was released directly into the coolant water without a free fall in a gas phase before making contact with the coolant. Corium (34.39 kg) consisting of uranium oxide and zirconium oxide with a weight ratio of 8:2 was superheated, and 22.54 kg of the 34.39 kg corium was passed through water contained in a transparent interaction vessel. An image of the corium jet behavior in the coolant was taken by a high-speed camera every millisecond. Thermocouple junctions installed in the vertical direction of the coolant were cut sequentially by the falling corium jet. It was clearly observed that the visualization image of the corium jet taken during the fuel-coolant interaction corresponded with the temperature variations in the direction of the falling melt. The corium penetrated through the coolant, and the jet leading edge velocity was 2.0 m/s. Debris smaller than 1 mm was 15% of the total weight of the debris collected after a fuel-coolant interaction test, and the mass median diameter was 2.9 mm.

  13. Measurements of tritium retention and removal on TFTR

    International Nuclear Information System (INIS)

    Skinner, C.H.; Blanchard, W.; Kamperschroer, J.

    1996-05-01

    Recent experiments on the Tokamak Fusion Test Reactor (TFTR) have afforded an opportunity to measure the retention of tritium in a graphite limiter that is subject to erosion, codeposition and high neutron flux. The tritium was injected by both gas puff and neutral beams. The isotopic mix of hydrogenic recycling was measured spectroscopically and the tritium fraction T/(H+D+T) increased to as high as 75%. Some tritium was pumped out during the experimental run and some removed in a subsequent campaign using various clean-up techniques. While the short term retention of tritium was high, various conditioning techniques were successful in removing ∌ 8,000 Ci and restoring the tritium inventory to a level well below the administrative limit

  14. Extensive Management Promotes Plant and Microbial Nitrogen Retention in Temperate Grassland

    Science.gov (United States)

    de Vries, Franciska T.; Bloem, Jaap; Quirk, Helen; Stevens, Carly J.; Bol, Roland; Bardgett, Richard D.

    2012-01-01

    Leaching losses of nitrogen (N) from soil and atmospheric N deposition have led to widespread changes in plant community and microbial community composition, but our knowledge of the factors that determine ecosystem N retention is limited. A common feature of extensively managed, species-rich grasslands is that they have fungal-dominated microbial communities, which might reduce soil N losses and increase ecosystem N retention, which is pivotal for pollution mitigation and sustainable food production. However, the mechanisms that underpin improved N retention in extensively managed, species-rich grasslands are unclear. We combined a landscape-scale field study and glasshouse experiment to test how grassland management affects plant and soil N retention. Specifically, we hypothesised that extensively managed, species-rich grasslands of high conservation value would have lower N loss and greater N retention than intensively managed, species-poor grasslands, and that this would be due to a greater immobilisation of N by a more fungal-dominated microbial community. In the field study, we found that extensively managed, species-rich grasslands had lower N leaching losses. Soil inorganic N availability decreased with increasing abundance of fungi relative to bacteria, although the best predictor of soil N leaching was the C/N ratio of aboveground plant biomass. In the associated glasshouse experiment we found that retention of added 15N was greater in extensively than in intensively managed grasslands, which was attributed to a combination of greater root uptake and microbial immobilisation of 15N in the former, and that microbial immobilisation increased with increasing biomass and abundance of fungi. These findings show that grassland management affects mechanisms of N retention in soil through changes in root and microbial uptake of N. Moreover, they support the notion that microbial communities might be the key to improved N retention through tightening linkages

  15. 7 CFR 800.147 - Maintenance and retention of records on delegations, designations, contracts, and approval of...

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Maintenance and retention of records on delegations, designations, contracts, and approval of scale testing organizations. 800.147 Section 800.147 Agriculture... and Forms (general) § 800.147 Maintenance and retention of records on delegations, designations...

  16. [Academic stress, desertion, and retention strategies for students in higher education].

    Science.gov (United States)

    SuĂĄrez-Montes, Nancy; DĂ­az-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.

  17. Glucocorticoid receptors and extinction retention deficits in the single prolonged stress model.

    Science.gov (United States)

    Knox, D; Nault, T; Henderson, C; Liberzon, I

    2012-10-25

    Single prolonged stress (SPS) is a rodent model of post traumatic stress disorder that is comprised of serial application of restraint (r), forced swim (fs), and ether (eth) followed by a 7-day quiescent period. SPS induces extinction retention deficits and it is believed that these deficits are caused by the combined stressful effect of serial exposure to r, fs, and eth. However, this hypothesis remains untested. Neurobiological mechanisms by which SPS induces extinction retention deficits are unknown, but SPS enhances glucocorticoid receptor (GR) expression in the hippocampus, which is critical for contextual modulation of extinction retrieval. Upregulation of GRs in extinction circuits may be a mechanism by which SPS induces extinction retention deficits, but this hypothesis has not been examined. In this study, we systematically altered the stressors that constitute SPS (i.e. r, fs, eth), generating a number of partial SPS (p-SPS) groups, and observed the effects SPS and p-SPSs had on extinction retention and GR levels in the hippocampus and prefrontal cortex (PFC). PFC GRs were assayed, because regions of the PFC are critical for maintaining extinction. We predicted that only exposure to full SPS would result in extinction retention deficits and enhance hippocampal and PFC GR levels. Only exposure to full SPS induced extinction retention deficits. Hippocampal and PFC GR expression was enhanced by SPS and most p-SPSs, however hippocampal GR expression was significantly larger following the full SPS exposure than all other conditions. Our findings suggest that the combined stressful effect of serial exposure to r, fs, and eth results in extinction retention deficits. The results also suggest that simple enhancements in GR expression in the hippocampus and PFC are insufficient to result in extinction retention deficits, but raise the possibility that a threshold-enhancement in hippocampal GR expression contributes to SPS-induced extinction retention deficits

  18. Employment and Satisfaction Outcomes From a Job Retention Intervention Delivered to Persons with Chronic Diseases

    Science.gov (United States)

    Allaire, Saralynn H.; Niu, Jingbo; LaValley, Michael P.

    2005-01-01

    Job retention services are recommended for people with chronic diseases based on their high risk for work disability. This randomized trial tested the effectiveness of a job retention intervention in a sample of employed persons with rheumatic diseases at risk for work disability. One hundred and twenty-two experimental participants received the


  19. Potential and limitations of phosphate retention media in water protection: a process-based review of laboratory and field-scale tests

    NARCIS (Netherlands)

    Klimeski, A.; Chardon, W.J.; Uusitalo, R.; Turtola, E.

    2012-01-01

    The application of phosphorus (P)-sorbing materials offers a possible solution for treating municipal wastewater and agricultural runoff. In this paper we discuss P retention and release mechanisms, and review studies on the P retention of different materials and their use as reactive media in

  20. Video Games Promote Saudi Children's English Vocabulary Retention

    Science.gov (United States)

    AlShaiji, Ohoud Abdullatif

    2015-01-01

    The objective of this study was to investigate the impact of Video Games and their role on promoting Saudi Kids' English vocabulary retention. The study attempted to answer whether there was a statistically significant difference (a = 0.05) between the Saudi children's subjects' mean score on the English vocabulary test due to using Video Games


  1. 76 FR 24089 - Credit Risk Retention

    Science.gov (United States)

    2011-04-29

    ... 17 CFR Part 246 Department of Housing and Urban Development 24 CFR Part 267 Credit Risk Retention... 2501-AD53 Credit Risk Retention AGENCIES: Office of the Comptroller of the Currency, Treasury (OCC..., Commission, FHFA, and HUD (the Agencies) are proposing rules to implement the credit risk retention...

  2. Effect of abutment modification and cement type on retention of cement-retained implant supported crowns.

    Directory of Open Access Journals (Sweden)

    Mitra Farzin

    2014-06-01

    Full Text Available Provisional cements are commonly used to facilitate retrievability of cement-retained fixed implant restorations; but compromised abutment preparation may affect the retention of implant-retained crowns.The purpose of this study was to investigate the effect of abutment design and type of luting agent on the retentive strength of cement-retained implant restorations.Two prefabricated abutments were attached to their corresponding analogs and embedded in an acrylic resin block. The first abutment (control group was left intact without any modifications. The screw access channel for the first abutment was completely filled with composite resin. In the second abutment, (test group the axial wall was partially removed to form an abutment with 3 walls. Wax models were made by CAD/CAM. Ten cast copings were fabricated for each abutment. The prepared copings were cemented on the abutments by Temp Bond luting agent under standardized conditions (n=20. The assemblies were stored in 100% humidity for one day at 37°C prior to testing. The cast crown was removed from the abutment using an Instron machine, and the peak removal force was recorded. Coping/abutment specimens were cleaned after testing, and the testing procedure was repeated for Dycal luting agent (n=20. Data were analyzed with two- way ANOVA (α=0.05.There was no significant difference in the mean transformed retention (Ln-R between intact abutments (4.90±0.37 and the abutments with 3 walls (4.83±0.25 using Dycal luting agent. However, in TempBond group, the mean transformed retention (Ln-R was significantly lower in the intact abutment (3.9±0.23 compared to the abutment with 3 walls (4.13±0.33, P=0.027.The retention of cement-retained implant restoration can be improved by the type of temporary cement used. The retention of cast crowns cemented to implant abutments with TempBond is influenced by the wall removal.

  3. Supporting nurse practitioner education: Preceptorship recruitment and retention

    Directory of Open Access Journals (Sweden)

    Eric Staples

    2018-04-01

    Full Text Available Objectives: Clinical experience is an essential component of nurse practitioner (NP education that relies heavily on preceptors. Recruitment and retention of preceptors is challenging due to many variables that can affect NP education and practice. We surveyed Canadian NP programs to understand their preceptorship structures, how they support preceptorship, and to identify gaps and challenges to recruitment and retention of preceptors. Methods: An 18-item survey, developed by the NP Education Interest Group, was distributed to 24 universities across 10 Canadian provinces. Construct validity and reliability was assessed by experienced NPs and NP faculty. Data were analyzed using relative frequency statistics and thematic analysis. Participants consisted of administrative staff and/or faculty designated as responsible for recruitment and retention of NP preceptors. Results: Seventeen returned surveys were analyzed and demonstrated more similarities than differences across Canada's NP programs, particularly related to barriers affecting recruitment and retention of preceptors. The findings identified NP programs have too many students for the number of available clinical sites/preceptors, resulting in overutilization, burnout, or refusal to take students. Competition with other health disciplines for clinical placements was identified as a challenge to placements. Respondents commented they lack time to recruit, provide follow-up, offer support, or seek preceptors' feedback due to competing work demands. They identified the need for standardized funding for preceptor remuneration and recognition across the country. Conclusion: The findings suggest the need for exploring a wider intraprofessional collaboration among graduate NP programs/faculty, clinical placement sites, and NPs to facilitate the recruitment and retention of preceptors.

  4. Flavor Dependent Retention of Remote Food Preference Memory.

    Science.gov (United States)

    Singh, Aditya; Kumar, Suraj; Singh, Vikram Pal; Das, Asish; Balaji, J

    2017-01-01

    Social Transmission of Food Preference (STFP) is a single trial non-aversive learning task that is used for testing non-spatial memory. This task relies on an accurate estimate of a change in food preference of the animals following social demonstration of a novel flavor. Conventionally this is done by providing two flavors of powdered food and later estimating the amount of food consumed for each of these flavors in a defined period of time. This is achieved through a careful measurement of leftover food for each of these flavors. However, in mice, only a small (~1 g) amount of food is consumed making the weight estimates error prone and thereby limiting the sensitivity of the paradigm. Using multiplexed video tracking, we show that the pattern of consumption can be used as a reliable reporter of memory retention in this task. In our current study, we use this as a measure and show that the preference for the demonstrated flavor significantly increases following demonstration and the retention of this change in preference during remote testing is flavor specific. Further, we report a modified experimental design for performing STFP that allows testing of change in preference among two flavors simultaneously. Using this paradigm, we show that during remote testing for thyme and basil demonstrated flavors, only basil demonstrated mice retain the change in preference while thyme demonstrated mice do not.

  5. Retention capacity of correlated surfaces.

    Science.gov (United States)

    Schrenk, K J; AraĂșjo, 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.

  6. Retention capacity of correlated surfaces

    OpenAIRE

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

    2014-01-01

    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.

  7. Retention of zinc and calcium from the human colon

    International Nuclear Information System (INIS)

    Sandstroem, B.C.; Cederblad, A.; Kivistoe, B.S.; Stenquist, B.; Andersson, H.

    1986-01-01

    Colonic retention of zinc and calcium was studied after installation during colonoscopy of 30 mumol of zinc and 6.4 mmol of calcium labeled with 65 Zn and 47 Ca, and measurement of the whole-body retention of the radionuclides. After cecal installation in nine patients, retention (day 13) of zinc was 3.5 +/- 2.1% (mean +/- SD) and of calcium 3.5 +/- 2.7%. The calculated mean absorption was 4.1% for zinc and 14.1% for calcium. Application at the hepatic flexure in four patients resulted in a mean retention (day 13) of 1.2% for zinc and 0.6% for calcium. Under prevailing conditions, colonic absorption of zinc is relatively small, compared to the uptake after oral administration. Colonic absorption of calcium could, however, account for a substantial part of the total calcium uptake

  8. Extrapolation of animal radionuclide retention data to man: Use of similarity ratios

    International Nuclear Information System (INIS)

    Thomas, J.M.; Eberhardt, L.L.

    1976-01-01

    A major problem in toxicology is the need for testing a myriad possible substances on several animal species as an aid in establishing standards for man. Particular interest in the problem of extrapolation to man is linked to a need for a method of obtaining transfer coefficients in food-chain models of ecosystems. Such a method could circumvent the necessity to test many species and compounds. Because of their particular interest in radioecology, the authors' studies were initiated using radionuclide retention data available in the literature. Since radionuclide retention should be a function of metabolism it follows that direct or indirect measures could be described by a ''power law'' based on body weight of the organism(s). However, when such power laws have been extended to interspecies comparisons the resulting power coefficients are usually substantially less than the value anticipated and seem to be different for each radionuclide. This paper proposes that interspecies comparisons ought to be based on the proportionality coefficient rather than the power parameter of the power function model and have called pairwise comparisons amongst species ''similarity ratios''. Retention data were examined from five non-ruminant species (including man) where several radionuclides with different physical properties were fed. Subsequently an expression was devised whereby an estimate of biological equilibrium level in man could be calculated using similar estimates from experiments using mice, rats or dogs. There are some statistical questions to resolve which have to do with the assumed frequency distribution for estimates of the proportionality coefficient. In addition, repeated use was made of the same data sets. (author)

  9. Illustrations in Text: A Retentional Role.

    Science.gov (United States)

    Duchastel, Philippe C.

    1981-01-01

    Describes the results of a study of the retentional role of illustrations in a text and their effect on enhancing long-term memory with 15-year-old secondary school students. Seven references are listed. (CHC)

  10. Comparison of iodine, krypton, and xenon retention efficiencies for various silver loaded adsorption media

    International Nuclear Information System (INIS)

    Huchton, R.L.; Tkachyk, J.W.; Taylor, J.T.; Motes, B.G.

    1985-03-01

    A comparison was made among various silver impregnated adsorption media to determine their iodine, krypton, and xenon retention efficiencies. The program consisted of three components. First, laboratory measurements of the noble gas retention efficiencies of commercially available adsorption media were determined as a function of relative humidity, sample duration, test cartridge geometry, and ambient air purge. Second, a literature survey was performed to evaluate the iodine species retention efficiencies of the selected media. Third, data associated with a media previously proposed for an emergency response air sampler were incorporated to enlarge the data base. 41 refs., 6 figs., 14 tabs

  11. Predictors of poor retention on antiretroviral therapy as a major HIV drug resistance early warning indicator in Cameroon: results from a nationwide systematic random sampling

    Directory of Open Access Journals (Sweden)

    Serge Clotaire Billong

    2016-11-01

    Full Text Available Abstract Background Retention on lifelong antiretroviral therapy (ART is essential in sustaining treatment success while preventing HIV drug resistance (HIVDR, especially in resource-limited settings (RLS. In an era of rising numbers of patients on ART, mastering patients in care is becoming more strategic for programmatic interventions. Due to lapses and uncertainty with the current WHO sampling approach in Cameroon, we thus aimed to ascertain the national performance of, and determinants in, retention on ART at 12 months. Methods Using a systematic random sampling, a survey was conducted in the ten regions (56 sites of Cameroon, within the “reporting period” of October 2013–November 2014, enrolling 5005 eligible adults and children. Performance in retention on ART at 12 months was interpreted following the definition of HIVDR early warning indicator: excellent (>85%, fair (85–75%, poor (<75; and factors with p-value < 0.01 were considered statistically significant. Results Majority (74.4% of patients were in urban settings, and 50.9% were managed in reference treatment centres. Nationwide, retention on ART at 12 months was 60.4% (2023/3349; only six sites and one region achieved acceptable performances. Retention performance varied in reference treatment centres (54.2% vs. management units (66.8%, p < 0.0001; male (57.1% vs. women (62.0%, p = 0.007; and with WHO clinical stage I (63.3% vs. other stages (55.6%, p = 0.007; but neither for age (adults [60.3%] vs. children [58.8%], p = 0.730 nor for immune status (CD4351–500 [65.9%] vs. other CD4-staging [59.86%], p = 0.077. Conclusions Poor retention in care, within 12 months of ART initiation, urges active search for lost-to-follow-up targeting preferentially male and symptomatic patients, especially within reference ART clinics. Such sampling strategy could be further strengthened for informed ART monitoring and HIVDR prevention perspectives.

  12. Odor-context effects in free recall after a short retention interval: a new methodology for controlling adaptation.

    Science.gov (United States)

    Isarida, Takeo; Sakai, Tetsuya; Kubota, Takayuki; Koga, Miho; Katayama, Yu; Isarida, Toshiko K

    2014-04-01

    The present study investigated context effects of incidental odors in free recall after a short retention interval (5 min). With a short retention interval, the results are not confounded by extraneous odors or encounters with the experimental odor and possible rehearsal during a long retention interval. A short study time condition (4 s per item), predicted not to be affected by adaptation to the odor, and a long study time condition (8 s per item) were used. Additionally, we introduced a new method for recovery from adaptation, where a dissimilar odor was briefly presented at the beginning of the retention interval, and we demonstrated the effectiveness of this technique. An incidental learning paradigm was used to prevent overshadowing from confounding the results. In three experiments, undergraduates (N = 200) incidentally studied words presented one-by-one and received a free recall test. Two pairs of odors and a third odor having different semantic-differential characteristics were selected from 14 familiar odors. One of the odors was presented during encoding, and during the test, the same odor (same-context condition) or the other odor within the pair (different-context condition) was presented. Without using a recovery-from-adaptation method, a significant odor-context effect appeared in the 4-s/item condition, but not in the 8-s/item condition. Using the recovery-from-adaptation method, context effects were found for both the 8- and the 4-s/item conditions. The size of the recovered odor-context effect did not change with study time. There were no serial position effects. Implications of the present findings are discussed.

  13. THE IMPACT OF GLOSS TYPES ON IRANIAN EFL STUDENTS’ READING COMPREHENSION AND LEXICAL RETENTION

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Farvardin

    2012-01-01

    Full Text Available Research has shown that the effect of marginal glosses on reading comprehension and vocabulary retention is a controversial issue. The purpose of this study was to investigate this issue among Iranian university EFL students. Three types of glosses were applied in this study: single gloss in participants’ first language (SL1G, single gloss in participants’ second language (SL2G, and multiple-choice gloss (MCG in participants’ second language. One hundred and twenty undergraduate students majoring in English Teaching at Azad University of Najafabad, Iran, read the texts under three conditions: SL1G, SL2G, and MCG. Afterwards, participants answered two vocabulary tests, one administered immediately after the reading test and another three weeks later. One-way repeated measures ANOVA and follow-up post hoc tests (p<.05 showed that MCG facilitated participants’ vocabulary learning while reading the text more than SLGs. The results of One-way ANOVA also revealed that SL2G was the most facilitative gloss type for the participants’ reading comprehension. The study illustrates how different types of textual glosses can affect both reading comprehension and vocabulary retention. Limitations and suggestions for future research are discussed.

  14. QUALITY OF WORK LIFE: THE DETERMINANTS OF JOB SATISFACTION AND JOB RETENTION AMONG RNs AND OHPs

    Directory of Open Access Journals (Sweden)

    Musrrat Parveen

    2017-03-01

    Full Text Available The health care industry (public and private in several countries, including Saudi Arabia, is facing high turnover rate among registered nurses (RNs and other health care professionals (OHPs. However, despite numerous studies that have been conducted in the past to tackle this phenomenon, we still believe that the functions and the connections between quality of work life (QWL, satisfaction and retention are still not thoroughly explored in the Middle East, particularly in Saudi Arabia. The aims of this current study are to examine the effects of demographic characteristics on the QWL dimensions and satisfaction, and the relationships between the QWL dimensions and satisfaction, and between satisfaction and retention among RNs and OHPs. A model was developed to link QWL, satisfaction and retention. A sample of 360 RNs and OHPs was collected in Jeddah, one of the major cities in Saudi Arabia. Multivariate analysis of variance and structural equation modeling were used to test the hypotheses. The results show that there is a significant difference between demographic and QWL dimensions and satisfaction. Satisfactions with personal growth and salary package were found to have significant positive impacts on overall retention. The paper provides a greater understanding of QWL, satisfaction and retention and their relationships with each other among the RNs and OHPs in public and private health care organizations in Saudi Arabia.

  15. The effectiveness of TBL with real patients in neurology education in terms of knowledge retention, in-class engagement, and learner reactions.

    Science.gov (United States)

    Alimoglu, Mustafa Kemal; Yardım, Selda; Uysal, Hilmi

    2017-03-01

    In our medical school, we changed from a lecture-based method to a team-based learning (TBL) method to teach "polyneuropathies" in the neurology clerkship starting from the 2014 to 2015 academic year. Real patients were used instead of written scenarios in TBL sessions. This study aimed to compare former lecture-based and the current TBL methods in terms of knowledge retention, in-class learner engagement, and learner reactions. First, we determined in-class engagement and satisfaction of the students for the lectures given in the 2013-2014 academic year. The following year, besides the same criteria, we also determined individual (IRAT) and group readiness test (GRAT) scores in the TBL group. End-of-clerkship exam scores for both groups were recorded. Additionally, opinions of patients about their experiences throughout the TBL process were determined. One year later (2015 for lecture and 2016 for TBL), both groups sat for an MCQ test to determine their knowledge retention levels. We found no difference between groups regarding end-of-clerkship exam scores. The mean knowledge retention test score of the TBL group was significantly higher than that of the lecture group (5.85 ± 1.74 vs. 3.28 ± 1.70). The differences between IRAT, GRAT, and retention test scores in the TBL group were significant. The mean student satisfaction score on a five-point scale was 3.01 ± 0.9 (median = 3) in the lecture group and 4.11 ± 1.1 (median = 4) in the TBL group. Our results seem encouraging for use of TBL performed with real patients in neurology education to achieve better long-term knowledge retention and higher in-class engagement and student satisfaction. Copyright © 2017 the American Physiological Society.

  16. Psychogenic Urinary Retention in Children: A Case Report

    Directory of Open Access Journals (Sweden)

    Kong-Sang Wan

    2010-10-01

    Full Text Available Psychogenic urinary retention occurs relatively infrequently in children and is less common than in adults. The influence of psychogenic factors on voiding generally results in an irritative syndrome, but rarely in urinary retention. A definitive diagnosis is established by excluding other pathological conditions. Evaluation includes urine culture, renal echography, spine magnetic resonance imaging, voiding cysto-urethrography, intravenous pyelography, and uroflowmetry. Here, we report on a 6-year-old girl with a 1-month history of voiding difficulty. Urology studies, including urine culture, revealed Escherichia coli, which was not present in preadmission urine cultures. Renal ultrasound and radiological images showed no gross abnormalities or vesicoureteral reflux, but uroflowmetry showed a low flow rate with residual urine. The results of imaging studies and pediatric psychiatric consultation led to a diagnosis of psychogenic urinary retention combined with urinary tract infection. Urinary rehabilitation included intermittent catheterization, bladder training, and supportive psychotherapy, after which the patient recovered and was discharged.

  17. Prediction of gas chromatography/electron capture detector retention times of chlorinated pesticides, herbicides, and organohalides by multivariate chemometrics methods

    International Nuclear Information System (INIS)

    Ghasemi, Jahanbakhsh; Asadpour, Saeid; Abdolmaleki, Azizeh

    2007-01-01

    A quantitative structure-retention relationship (QSRR) study, has been carried out on the gas chromatograph/electron capture detector (GC/ECD) system retention times (t R s) of 38 diverse chlorinated pesticides, herbicides, and organohalides by using molecular structural descriptors. Modeling of retention times of these compounds as a function of the theoretically derived descriptors was established by multiple linear regression (MLR) and partial least squares (PLS) regression. The stepwise regression using SPSS was used for the selection of the variables that resulted in the best-fitted models. Appropriate models with low standard errors and high correlation coefficients were obtained. Three types of molecular descriptors including electronic, steric and thermodynamic were used to develop a quantitative relationship between the retention times and structural properties. MLR and PLS analysis has been carried out to derive the best QSRR models. After variables selection, MLR and PLS methods used with leave-one-out cross validation for building the regression models. The predictive quality of the QSRR models were tested for an external prediction set of 12 compounds randomly chosen from 38 compounds. The PLS regression method was used to model the structure-retention relationships, more accurately. However, the results surprisingly showed more or less the same quality for MLR and PLS modeling according to squared regression coefficients R 2 which were 0.951 and 0.948 for MLR and PLS, respectively

  18. Thorough investigation of the retention mechanisms and retention behavior of amides and sulfonamides on amino column in hydrophilic interaction liquid chromatography.

    Science.gov (United States)

    Jovanović, Marko; Stojanović, Biljana Jančić

    2013-08-02

    In this paper detailed analysis of a mixture of four amides (tropicamide, nicotinamide, tiracetam, and piracetam) and six sulfonamides (sulfanilamide, sulfacetamide, sulfamethoxazole, sulfafurazole, furosemide, and bumetanide) on aminopropyl column in hydrophilic interaction chromatography (HILIC) was carried out. Since, there are no papers on the topic of the assessment of the contribution of ion-exchange retention mechanism involved in the separation of the acidic compounds on aminopropyl column in HILIC mode, the authors utilized the retention data of the acidic sulfonamides for this purpose. Next, broad range of the aqueous buffer concentrations in the mobile phase was examined providing the separation under either HILIC or RP conditions. Turning points between these two mechanisms were determined and then the fitting of the experimental data in the localized and non-localized adsorption models in both RP and HILIC regions was assessed. Since not many papers in the literature were dealing with the estimation of factor influence on the retention behavior of neutral and acidic compounds on aminopropyl column in HILIC, Box-Behnken design and Response Surface Methodology were applied. On the basis of the obtained data, ten quadratic models were proposed and their adequacy was confirmed using ANOVA test. Furthermore, retention data was graphically evaluated by the construction of 3D response surface plots. Finally, good predictive ability of the suggested models was proved with five additional verification experiments. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Expectancy of an open-book test decreases performance on a delayed closed-book test.

    Science.gov (United States)

    Agarwal, Pooja K; Roediger, Henry L

    2011-11-01

    Two experiments examined the influence of practice with, and the expectancy of, open-book tests (students viewed studied material while taking the test) versus closed-book tests (students completed the test without viewing the studied material) on delayed retention and transfer. Using GRE materials specifically designed for open-book testing, participants studied passages and then took initial open- or closed-book tests. Open-book testing led to better initial performance than closed-book testing, but on a delayed criterial (closed-book) test both types of testing produced similar retention after a two-day delay in Experiment 1. In Experiment 2 participants were informed in advance about the type of delayed criterial test to expect (open- or closed-book). Expecting an open-book test (relative to a closed-book test) decreased participants' time spent studying and their delayed test performance on closed-book comprehension and transfer tests, demonstrating that test expectancy can influence long-term learning. Expectancy of open-book tests may impair long-term retention and transfer compared to closed-book tests, despite superior initial performance on open-book tests and students' preference for open-book tests.

  20. The Effect of Context (Humorous vs. Non-humorous on Vocabulary Acquisition and Retention of Iranian EFL Learners

    Directory of Open Access Journals (Sweden)

    Mohsen Ghaffari

    2012-11-01

    Full Text Available For almost four decades, ESL/EFL scholars have been trying to find which learning type, contextualized vs. decontextualized, leads to better vocabulary acquisition and retention. In an attempt to solve this problem, this study tried to examine the possible effectiveness of using humorous context on vocabulary acquisition and retention. Another issue that was undertaken in the present study was comparing the efficiency of contextualized and decontextualized vocabulary learning and retention. For this purpose, 58 Iranian EFL learners were categorized into 3 groups: a humorous, b non-humorous, and c decontextualized. The findings were analyzed using one-way ANOVA and Tukey post hoc test. As the results revealed, the participants in decontextualized group outperformed the participants in both humorous and non-humorous groups. However, it should be noted that the performance of humorous group was significantly better than the performance of non-humorous group.

  1. Technetium Retention In WTP Law Glass With Recycle Flow-Sheet DM10 Melter Testing VSL-12R2640-1 REV 0

    International Nuclear Information System (INIS)

    Abramowitz, Howard; Callow, Richard A.; Joseph, Innocent

    2012-01-01

    Melter tests were conducted to determine the retention of technetium and other volatiles in glass while processing simulated Low Activity Waste (LAW) streams through a DM10 melter equipped with a prototypical off-gas system that concentrates and recycles fluid effiuents back to the melter feed. To support these tests, an existing DM10 system installed at Vitreous State Laboratory (VSL) was modified to add the required recycle loop. Based on the Hanford Tank Waste Treatment and Immobilization Plant (WTP) LAW off-gas system design, suitably scaled versions of the Submerged Bed Scrubber (SBS), Wet Electrostatic Precipitator (WESP), and TLP vacuum evaporator were designed, built, and installed into the DM10 system. Process modeling was used to support this design effort and to ensure that issues associated with the short half life of the 99m Tc radioisotope that was used in this work were properly addressed and that the system would be capable of meeting the test objectives. In particular, this required that the overall time constant for the system was sufficiently short that a reasonable approach to steady state could be achieved before the 99m Tc activity dropped below the analytical limits of detection. The conceptual design, detailed design, flow sheet development, process model development, Piping and Instrumentation Diagram (P and ID) development, control system design, software design and development, system fabrication, installation, procedure development, operator training, and Test Plan development for the new system were all conducted during this project. The new system was commissioned and subjected to a series of shake-down tests before embarking on the planned test program. Various system performance issues that arose during testing were addressed through a series of modifications in order to improve the performance and reliability of the system. The resulting system provided a robust and reliable platform to address the test objectives

  2. TECHNETIUM RETENTION IN WTP LAW GLASS WITH RECYCLE FLOW-SHEET DM10 MELTER TESTING VSL-12R2640-1 REV 0

    Energy Technology Data Exchange (ETDEWEB)

    Abramowitz, Howard [Catholic Univ. of America, Washington, DC (United States). Vitreous State Lab.; Brandys, Marek [Catholic Univ. of America, Washington, DC (United States). Vitreous State Lab.; Cecil, Richard [Catholic Univ. of America, Washington, DC (United States). Vitreous State Lab.; D& #x27; Angelo, Nicholas [Catholic Univ. of America, Washington, DC (United States). Vitreous State Lab.; Matlack, Keith S. [Catholic Univ. of America, Washington, DC (United States). Vitreous State Lab.; Muller, Isabelle S. [Catholic Univ. of America, Washington, DC (United States). Vitreous State Lab.; Pegg, Ian L. [Energy Solutions, Federal EPC, Inc., Columbia, MD (United States); Callow, Richard A. [Energy Solutions, Federal EPC, Inc., Columbia, MD (United States); Joseph, Innocent

    2012-12-11

    Melter tests were conducted to determine the retention of technetium and other volatiles in glass while processing simulated Low Activity Waste (LAW) streams through a DM10 melter equipped with a prototypical off-gas system that concentrates and recycles fluid effiuents back to the melter feed. To support these tests, an existing DM10 system installed at Vitreous State Laboratory (VSL) was modified to add the required recycle loop. Based on the Hanford Tank Waste Treatment and Immobilization Plant (WTP) LAW off-gas system design, suitably scaled versions of the Submerged Bed Scrubber (SBS), Wet Electrostatic Precipitator (WESP), and TLP vacuum evaporator were designed, built, and installed into the DM10 system. Process modeling was used to support this design effort and to ensure that issues associated with the short half life of the {sup 99m}Tc radioisotope that was used in this work were properly addressed and that the system would be capable of meeting the test objectives. In particular, this required that the overall time constant for the system was sufficiently short that a reasonable approach to steady state could be achieved before the {sup 99m}Tc activity dropped below the analytical limits of detection. The conceptual design, detailed design, flow sheet development, process model development, Piping and Instrumentation Diagram (P&ID) development, control system design, software design and development, system fabrication, installation, procedure development, operator training, and Test Plan development for the new system were all conducted during this project. The new system was commissioned and subjected to a series of shake-down tests before embarking on the planned test program. Various system performance issues that arose during testing were addressed through a series of modifications in order to improve the performance and reliability of the system. The resulting system provided a robust and reliable platform to address the test objectives.

  3. Mixed evidence for the potential of non-invasive transcutaneous vagal nerve stimulation to improve the extinction and retention of fear.

    Science.gov (United States)

    Burger, A M; Verkuil, B; Fenlon, H; Thijs, L; Cools, L; Miller, H C; Vervliet, B; Van Diest, I

    2017-10-01

    Extinction memories are fragile and their formation has been proposed to partially rely on vagus nerve activity. We tested whether stimulating the auricular branch of the vagus (transcutaneous VNS; tVNS) accelerates extinction and reduces spontaneous recovery of fear. Forty-two healthy students participated in a 3-day fear conditioning study, where we tested fear acquisition (day 1), fear extinction (day 2) and the retention of the extinction memory (day 3). During extinction, participants were randomly allocated to receive tVNS or sham stimulation concurrently with each CS presentation. During the acquisition and retention phases, all participants received sham stimulation. Indexes of fear included US-expectancy, startle blink EMG and skin conductance responses. Results showed successful acquisition and extinction of fear in all measures. tVNS facilitated the extinction of declarative fear (US expectancy ratings), but did not promote a stronger retention of the declarative extinction memory. No clear effects of tVNS on extinction and retention of extinction were found for the psychophysiological indexes. The present findings provide tentative indications that tVNS could be a promising tool to improve fear extinction and call for larger scale studies to replicate these effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Heavy metals and color retention by a synthesized inorganic membrane

    Directory of Open Access Journals (Sweden)

    A. Chougui

    2014-11-01

    The ceramic membranes were tested for the removal of cadmium, zinc, Methylene Blue and Malachite Green from water under a pressure of 5 bar and a treatment time of 2 h. Liquid filtration and flow tests through these membranes resulted in a rejection rate of 100% for Methylene Blue and Malachite Green. This paper also presents the ability of the tubular membrane prepared to separate heavy metals (cadmium and zinc from their synthetic aqueous solutions. The influence of the applied pressure, feed solute concentration, feed pH on the rejection of cadmium and zinc ions was studied. Retention rates of cadmium and zinc ions of 100% were observed for an initial feed concentration of 10−4 mol/L.

  5. Short-term Retention of Relational Memory in Amnesia Revisited: Accurate Performance Depends on Hippocampal Integrity

    Directory of Open Access Journals (Sweden)

    Lydia T.S. Yee

    2014-01-01

    Full Text Available Traditionally, it has been proposed that the hippocampus and adjacent medial temporal lobe cortical structures are selectively critical for long-term declarative memory, which entails memory for inter-item and item-context relationships. Whether the hippocampus might also contribute to short-term retention of relational memory representations has remained controversial. In two experiments, we revisit this question by testing memory for relationships among items embedded in scenes using a standard working memory trial structure in which a sample stimulus is followed by a brief delay and the corresponding test stimulus. In each experimental block, eight trials using different exemplars of the same scene were presented. The exemplars contained the same items but with different spatial relationships among them. By repeating the pictures across trials, any potential contributions of item or scene memory to performance were minimized, and relational memory could be assessed more directly than has been done previously. When test displays were presented, participants indicated whether any of the item-location relationships had changed. Then, regardless of their responses (and whether any item did change its location, participants indicated on a forced-choice test, which item might have moved, guessing if necessary. Amnesic patients were impaired on the change detection test, and were frequently unable to specify the change after having reported correctly that a change had taken place. Comparison participants, by contrast, frequently identified the change even when they failed to report the mismatch, an outcome that speaks to the sensitivity of the change specification measure. These results confirm past reports of hippocampal contributions to short-term retention of relational memory representations, and suggest that the role of the hippocampus in memory has more to do with relational memory requirements than the length of a retention interval.

  6. Retentive strength of different intracanal posts in restorations of anterior primary teeth: an in vitro study

    Directory of Open Access Journals (Sweden)

    Mahtab Memarpour

    2013-11-01

    Full Text Available Objectives To determine the retentive strength and failure mode of undercut composite post, glass fiber post and polyethylene fiber post luted with flowable composite resin and resin-cement. Materials and Methods Coronal parts of 120 primary canine teeth were sectioned and specimens were treated endodontically. The teeth were randomly divided into 6 groups (n = 20. Prepared root canals received intracanal retainers with a short composite post, undercut composite post, glass fiber post luted with flowable resin or resin-cement, and polyethylene fiber post luted with flowable resin or resin-cement. After crown reconstruction, samples were tested for retentive strength and failure mode. Statistical analysis was done with one-way ANOVA and Tukey tests (p < 0.05. Results There were statistically significant differences between groups (p = 0.001. Mean bond strength in the undercut group was significantly greater than in the short composite post (p = 0.030, and the glass fiber post (p = 0.001 and the polyethylene fiber post group luted with resin-cement (p = 0.008. However, the differences between the undercut group and the groups with flowable composite as the luting agent were not significant (p = 0.068, p = 0.557. Adhesive failure was more frequent in the fiber post groups. Conclusions Although the composite post with undercutting showed the greatest resistance to dislodgement, fiber posts cemented with flowable composite resin provided acceptable results in terms of retentive strength and fracture mode.

  7. Stellar Wind Retention and Expulsion in Massive Star Clusters

    Science.gov (United States)

    Naiman, J. P.; Ramirez-Ruiz, E.; Lin, D. N. C.

    2018-05-01

    Mass and energy injection throughout the lifetime of a star cluster contributes to the gas reservoir available for subsequent episodes of star formation and the feedback energy budget responsible for ejecting material from the cluster. In addition, mass processed in stellar interiors and ejected as winds has the potential to augment the abundance ratios of currently forming stars, or stars which form at a later time from a retained gas reservoir. Here we present hydrodynamical simulations that explore a wide range of cluster masses, compactnesses, metallicities and stellar population age combinations in order to determine the range of parameter space conducive to stellar wind retention or wind powered gas expulsion in star clusters. We discuss the effects of the stellar wind prescription on retention and expulsion effectiveness, using MESA stellar evolutionary models as a test bed for exploring how the amounts of wind retention/expulsion depend upon the amount of mixing between the winds from stars of different masses and ages. We conclude by summarizing some implications for gas retention and expulsion in a variety of compact (σv ≳ 20 kms-1) star clusters including young massive star clusters (105 â‰Č M/M⊙ â‰Č 107, age â‰Č 500 Myrs), intermediate age clusters (105 â‰Č M/M⊙ â‰Č 107, age ≈ 1 - 4 Gyrs), and globular clusters (105 â‰Č M/M⊙ â‰Č 107, age ≳ 10 Gyrs).

  8. Deuterium retention in liquid lithium

    International Nuclear Information System (INIS)

    Baldwin, M.J.; Doerner, R.P.; Luckhardt, S.C.; Conn, R.W.

    2002-01-01

    Measurements of deuterium retention in samples of lithium exposed in the liquid state to deuterium plasma are reported. Retention was measured as a function of plasma ion dose in the range 6x10 19 -4x10 22 D atoms and exposure temperature between 523 and 673 K using thermal desorption spectrometry. The results are consistent with the full uptake of all deuterium ions incident on the liquid metal surface and are found to be independent of the temperature of the liquid lithium over the range explored. Full uptake, consistent with very low recycling, continues until the sample is volumetrically converted to lithium deuteride. This occurs for exposure temperatures where the gas pressure during exposure was both below and slightly above the corresponding decomposition pressure for LiD in Li. (author)

  9. Artisan retention in an organisation in South Africa

    Directory of Open Access Journals (Sweden)

    Lariska van Rooyen

    2010-11-01

    Research purpose: The objective of this study was to investigate the factors that are important for artisan retention at a South African organisation. Motivation for the study: Organisations that employ artisans need to understand what the main reasons are for keeping or losing artisans from the perspective of the artisans themselves. This information can be used to plan and implement interventions to deal with artisan retention in organisations. Research design, approach and method: A qualitative design was used and a purposive sample was taken (n = 14. A biographical questionnaire was administered and semi-structured interviews were conducted to gather data from artisans. Main findings: Remuneration had the highest rank of all the factors for the retention of artisans, closely followed by development opportunities. Other factors that were perceived as important for artisan retention included equality, recognition, management and the working environment, and working relationships. Practical implications: Organisations that employ artisans should especially attend to their remuneration and development opportunities. Contribution: The results of this study add to the knowledge of why artisans remain with a specific organisation.

  10. The Effect of CTL Approach Based on NHT Learning Model toward Students’ motivation, Science Achievement, and Retention

    Directory of Open Access Journals (Sweden)

    Muhammad Mifta Fausan

    2017-07-01

    Full Text Available The learning is an interaction process between students and their environment in order to improve good behavior. The results of observation which has been done in grade V SDN No. 4 Tanjung Batu showed that the students’ motivation and science achievement were low. This was becaused by the learning process which was still product oriented (based on material content, consequently, this lead to limit the learning is merely on memorizing concept activities. One of the learning approach that can be used to solve this problem is the Contextual Teaching and Learning (CTL based on Numbered Head Together (NHT. This research aims to determine the effect of CTL based on NHT toward student’s motivation, science achievement, and retention. Subjects in this research were the students of grade V SDN No. 4 Tanjung Batu. This research is a quasi-experimental using post-test only control design. The data obtained were analyzed by using descriptive and inferential statistical analysis. The research instruments were observation sheets and written test. The results showed that there was significant effect of CTL based on NHT toward students’ motivation, science achievement, and retention. It can be seen from the independent sample t-test results which showed significant value less than 0.05.

  11. Irradiation effects test Series Scoping Test 1: test results report

    International Nuclear Information System (INIS)

    Quapp, W.J.; Allison, C.M.; Farrar, L.C.

    1977-09-01

    The report describes the results of the first scoping test in the Irradiation Effects Test Series conducted by the Thermal Fuels Behavior Program, which is part of the Water Reactor Research Program of EG and G Idaho, Inc. The research is sponsored by the United States Nuclear Regulatory Commission. This test used an unirradiated, three-foot-long, PWR-type fuel rod. The objective of this test was to thoroughly evaluate the remote fabrication procedures to be used for irradiated rods in future tests, handling plans, and reactor operations. Additionally, selected fuel behavior data were obtained. The fuel rod was subjected to a series of preconditioning power cycles followed by a power increase which brought the fuel rod power to about 20.4 kW/ft peak linear heat rating at a coolant mass flux of 1.83 x 10 6 lb/hr-ft 2 . Film boiling occurred for a period of 4.8 minutes following flow reductions to 9.6 x 10 5 and 7.5 x 10 5 lb/hr-ft 2 . The test fuel rod failed following reactor shutdown as a result of heavy internal and external cladding oxidation and embrittlement which occurred during the film boiling operation

  12. Is cunnilingus-assisted orgasm a male sperm-retention strategy?

    Science.gov (United States)

    Pham, Michael N; Shackelford, Todd K; Sela, Yael; Welling, Lisa Lm

    2013-06-06

    We secured data from 243 men in committed, sexual, heterosexual relationships to test the sperm retention hypothesis of oral sex. We predicted that, among men who perform cunnilingus on their partner, those at greater risk of sperm competition are more likely to perform cunnilingus until their partner achieves orgasm (Prediction 1), and that, among men who ejaculate during penile-vaginal intercourse and whose partner experiences a cunnilingus-assisted orgasm, ejaculation will occur during the brief period in which female orgasm might function to retain sperm (Prediction 2). The results support Prediction 1 but not Prediction 2. We discuss limitations of the current research and discuss how these results may be more consistent with alternative hypotheses regarding female orgasm and oral sex.

  13. Is Cunnilingus-Assisted Orgasm a Male Sperm-Retention Strategy?

    Directory of Open Access Journals (Sweden)

    Michael N. Pham

    2013-04-01

    Full Text Available We secured data from 243 men in committed, sexual, heterosexual relationships to test the sperm retention hypothesis of oral sex. We predicted that, among men who perform cunnilingus on their partner, those at greater risk of sperm competition are more likely to perform cunnilingus until their partner achieves orgasm (Prediction 1, and that, among men who ejaculate during penile-vaginal intercourse and whose partner experiences a cunnilingus-assisted orgasm, ejaculation will occur during the brief period in which female orgasm might function to retain sperm (Prediction 2. The results support Prediction 1 but not Prediction 2. We discuss limitations of the current research and discuss how these results may be more consistent with alternative hypotheses regarding female orgasm and oral sex.

  14. Assessing Potential Additional PFAS Retention Processes in the Subsurface

    Science.gov (United States)

    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

  15. Employer retention strategies and their effect on nurses' job satisfaction and intent to stay.

    Science.gov (United States)

    Ellenbecker, Carol Hall; Samia, Linda; Cushman, Margaret J; Porell, Frank W

    2007-01-01

    Faced with a nursing shortage and anticipated increase in demand, home care agencies are implementing retention strategies with little knowledge of their effectiveness. The purpose of this study is to describe the strategies implemented and their effect on nurse job satisfaction and intention to leave. Data were collected from a random sample of 123 New England agencies during in-person interviews. Most agencies reported implementing multiple recruitment and retention strategies. Regression results suggest that the effects of employer retention strategy on nurses' intent to stay are the indirect result of its effects on job satisfaction. The only retention intervention that made a statistically significant difference in job satisfaction was shared governance, and no retention strategy directly affected nurses' intention to stay in their jobs.

  16. EFFECTS OF ANISOMYCIN ON RETENTION OF THE PASSIVE-AVOIDANCE HABIT AS A FUNCTION OF AGE

    Energy Technology Data Exchange (ETDEWEB)

    Davis, Hasker P.; Rosenzweig, Mark R.; Kinkade, Patrick T.; Bennett, Edward L.

    1980-09-01

    Three age groups of male Swiss albino CD-1 mice (2-3 mo, 6-7 mo, and 14-15 mo) were treated with a 120 mg/kg dose of the protein synthesis inhibitor anisomycin or with an equal volume of saline at various times before and after training (20 min pretraining, 0, 10, 30, and 180 min posttraining) in a shock motivated passive-avoidance task. Young (2-3 mo) and intermediate-aged (6-7 mo) mice treated with anisomycin before or immediately after training demonstrated impaired retention at a 7 day test, but retention was normal for mice injected 10, 30, or 180 min posttraining. The older mice (14-15 mo) showed similar results, with one exception: Those older mice injected with anisomycin 10 min posttraining were significantly impared in retention as compared to older saline controls and to identically treated young or intermediate-aged mice. The prolonged gradient of retrograde amnesia demonstrated by older mice could not be accounted for by impaired acquisition, impaired short-term memory, altered spontaneous locomotor activity, or differential inhibition of brain protein synthesis.

  17. Methods to improve patient recruitment and retention in stroke trials

    DEFF Research Database (Denmark)

    Berge, Eivind; Stapf, Christian; Al-Shahi Salman, Rustam

    2016-01-01

    Background: The success of randomized-controlled stroke trials is dependent on the recruitment and retention of a sufficient number of patients, but fewer than half of all trials meet their target number of patients. Methods: We performed a search and review of the literature, and conducted...... a survey and workshop among 56 European stroke trialists, to identify barriers, suggest methods to improve recruitment and retention, and make a priority list of interventions that merit further evaluation. Results: The survey and workshop identified a number of barriers to patient recruitment...... and retention, from patients’ incapacity to consent, to handicaps that prevent patients from participation in trial-specific follow-up. Methods to improve recruitment and retention may include simple interventions with individual participants, funding of research networks, and reimbursement of new treatments...

  18. Influence of impurities on the fuel retention in fusion reactors

    International Nuclear Information System (INIS)

    Reinhart, Michael

    2015-01-01

    The topic of this thesis is the influence of plasma impurities on the hydrogen retention in metals, in the scope of plasma-wall-interaction research for fusion reactors. This is addressed experimentally and by modelling. The mechanisms of the hydrogen retention are influenced by various parameters like the wall temperature, ion energy, flux and fluence as well as the plasma composition. The plasma composition is a relevant factor for hydrogen retention in fusion reactors, as their plasma will also contain impurities like helium or seeded impurities like argon. The experiments treated in this thesis were performed in the linear plasma generator PSI-2 at Forschungszentrum Juelich, and are divided in 3 parts: The first experiments cover the plasma diagnostics, most importantly the measurement of the impurity ion concentration in the plasma by optical emission spectroscopy. This is a requirement for the later experiments with mixed plasmas. Diagnostics like Langmuir probe measurements are not applicable for this task because they do not distinguish different ionic species. The results also show that the impurity ion concentrations cannot be simply concluded from the neutral gas input to the plasma source, because the relation between the neutral gas concentration and impurity ion concentration is not linear. The second and main part of the experiments covers the exposure of tungsten samples to deuterium plasmas. In the experiments, the impurity ion type and concentration is variated, to verify the general influence of helium and argon on the deuterium retention in tungsten samples exposed at low temperatures. It shows that helium impurities reduce the amount of retained deuterium by a factor of 3, while argon impurities slightly increase the total retention, compared to exposures to a pure deuterium plasma. Cross-sections of the exposed tungsten surfaces via TEM-imaging reveal a 12-15 nm deep helium nanobubble layer at the surface of the sample, while for the cases of

  19. Influence of impurities on the fuel retention in fusion reactors

    Energy Technology Data Exchange (ETDEWEB)

    Reinhart, Michael

    2015-07-01

    The topic of this thesis is the influence of plasma impurities on the hydrogen retention in metals, in the scope of plasma-wall-interaction research for fusion reactors. This is addressed experimentally and by modelling. The mechanisms of the hydrogen retention are influenced by various parameters like the wall temperature, ion energy, flux and fluence as well as the plasma composition. The plasma composition is a relevant factor for hydrogen retention in fusion reactors, as their plasma will also contain impurities like helium or seeded impurities like argon. The experiments treated in this thesis were performed in the linear plasma generator PSI-2 at Forschungszentrum Juelich, and are divided in 3 parts: The first experiments cover the plasma diagnostics, most importantly the measurement of the impurity ion concentration in the plasma by optical emission spectroscopy. This is a requirement for the later experiments with mixed plasmas. Diagnostics like Langmuir probe measurements are not applicable for this task because they do not distinguish different ionic species. The results also show that the impurity ion concentrations cannot be simply concluded from the neutral gas input to the plasma source, because the relation between the neutral gas concentration and impurity ion concentration is not linear. The second and main part of the experiments covers the exposure of tungsten samples to deuterium plasmas. In the experiments, the impurity ion type and concentration is variated, to verify the general influence of helium and argon on the deuterium retention in tungsten samples exposed at low temperatures. It shows that helium impurities reduce the amount of retained deuterium by a factor of 3, while argon impurities slightly increase the total retention, compared to exposures to a pure deuterium plasma. Cross-sections of the exposed tungsten surfaces via TEM-imaging reveal a 12-15 nm deep helium nanobubble layer at the surface of the sample, while for the cases of

  20. Effects of Embodied Learning and Digital Platform on the Retention of Physics Content: Centripetal Force.

    Science.gov (United States)

    Johnson-Glenberg, Mina C; Megowan-Romanowicz, Colleen; Birchfield, David A; Savio-Ramos, Caroline

    2016-01-01

    Embodiment theory proposes that knowledge is grounded in sensorimotor systems, and that learning can be facilitated to the extent that lessons can be mapped to these systems. This study with 109 college-age participants addresses two overarching questions: (a) how are immediate and delayed learning gains affected by the degree to which a lesson is embodied, and (b) how do the affordances of three different educational platforms affect immediate and delayed learning? Six 50 min-long lessons on centripetal force were created. The first factor was the degree of embodiment with two levels: (1) low and (2) high. The second factor was platform with three levels: (1) a large scale "mixed reality" immersive environment containing both digital and hands-on components called SMALLab , (2) an interactive whiteboard system, and (3) a mouse-driven desktop computer. Pre-tests, post-tests, and 1-week follow-up (retention or delayed learning gains) tests were administered resulting in a 2 × 3 × 3 design. Two knowledge subtests were analyzed, one that relied on more declarative knowledge and one that relied on more generative knowledge, e.g., hand-drawing vectors. Regardless of condition, participants made significant immediate learning gains from pre-test to post-test. There were no significant main effects or interactions due to platform or embodiment on immediate learning. However, from post-test to follow-up the level of embodiment interacted significantly with time, such that participants in the high embodiment conditions performed better on the subtest devoted to generative knowledge questions. We posit that better retention of certain types of knowledge can be seen over time when more embodiment is present during the encoding phase. This sort of retention may not appear on more traditional factual/declarative tests. Educational technology designers should consider using more sensorimotor feedback and gestural congruency when designing and opportunities for instructor

  1. Effects of Embodied Learning and Digital Platform on the Retention of Physics Content: Centripetal Force

    Science.gov (United States)

    Johnson-Glenberg, Mina C.; Megowan-Romanowicz, Colleen; Birchfield, David A.; Savio-Ramos, Caroline

    2016-01-01

    Embodiment theory proposes that knowledge is grounded in sensorimotor systems, and that learning can be facilitated to the extent that lessons can be mapped to these systems. This study with 109 college-age participants addresses two overarching questions: (a) how are immediate and delayed learning gains affected by the degree to which a lesson is embodied, and (b) how do the affordances of three different educational platforms affect immediate and delayed learning? Six 50 min-long lessons on centripetal force were created. The first factor was the degree of embodiment with two levels: (1) low and (2) high. The second factor was platform with three levels: (1) a large scale “mixed reality” immersive environment containing both digital and hands-on components called SMALLab, (2) an interactive whiteboard system, and (3) a mouse-driven desktop computer. Pre-tests, post-tests, and 1-week follow-up (retention or delayed learning gains) tests were administered resulting in a 2 × 3 × 3 design. Two knowledge subtests were analyzed, one that relied on more declarative knowledge and one that relied on more generative knowledge, e.g., hand-drawing vectors. Regardless of condition, participants made significant immediate learning gains from pre-test to post-test. There were no significant main effects or interactions due to platform or embodiment on immediate learning. However, from post-test to follow-up the level of embodiment interacted significantly with time, such that participants in the high embodiment conditions performed better on the subtest devoted to generative knowledge questions. We posit that better retention of certain types of knowledge can be seen over time when more embodiment is present during the encoding phase. This sort of retention may not appear on more traditional factual/declarative tests. Educational technology designers should consider using more sensorimotor feedback and gestural congruency when designing and opportunities for instructor

  2. Recycling retention functions

    International Nuclear Information System (INIS)

    Skrable, K.W.; Chabot, G.E.; Johnson, M.H.

    1981-01-01

    Beginning with the concept of any number of physiologically meaningful compartments that recycle material with a central extracellular fluid compartment and considering various excretion pathways, we solve the differential equations describing the kinetics by the method of Laplace to obtain concise algebraic expressions for the retentions. These expressions contain both fundamental and eigenvalue rate constants; the eigenvalue rate constants are obtained from the solution of a polynomial incorporating the fundamental rate constants. Mathematically exact expressions that predict the biodistribution resulting from continuous uptakes are used to obtain very simple mathematically exact steady state expressions as well as approximate expressions applicable to any time. These steady state and approximate expressions contain only the fundamental rate constants; also, they include a recycling factor that describes the increase in the biodistributions because of recycling. To obtain the values of the fundamental rate constants, short term kinetics studies along with data on the long term distributions are suggested. Retention functions obtained in this way predict both the short term and long term distributions; they therefore are useful in the interpretation of bioassay data and in the estimation of internal doses

  3. Estimation of hydraulic conductivities of Yucca Mountain tuffs from sorptivity and water retention measurements

    International Nuclear Information System (INIS)

    Zimmerman, R.W.; Bodvarsson, G.S.

    1995-06-01

    The hydraulic conductivity functions of the matrix rocks at Yucca Mountain, Nevada, are among the most important data needed as input for the site-scale hydrological model of the unsaturated zone. The difficult and time-consuming nature of hydraulic conductivity measurements renders it infeasible to directly measure this property on large numbers of cores. Water retention and sorptivity measurements, however, can be made relatively rapidly. The sorptivity is, in principle, a unique functional of the conductivity and water retention functions. It therefore should be possible to invert sorptivity and water retention measurements in order to estimate the conductivity; the porosity is the only other parameter that is required for this inversion. In this report two methods of carrying out this inversion are presented, and are tested against a limited data set that has been collected by Flint et al. at the USGS on a set of Yucca Mountain tuffs. The absolute permeability is usually predicted by both methods to within an average error of about 0.5 - 1.0 orders of magnitude. The discrepancy appears to be due to the fact that the water retention curves have only been measured during drainage, whereas the imbibition water retention curve is the one that is relevant to sorptivity measurements. Although the inversion methods also yield predictions of the relative permeability function, there are yet no unsaturated hydraulic conductivity data against which to test these predictions

  4. Irradiation effects test series, test IE-5. Test results report

    International Nuclear Information System (INIS)

    Croucher, D.W.; Yackle, T.R.; Allison, C.M.; Ploger, S.A.

    1978-01-01

    Test IE-5, conducted in the Power Burst Facility at the Idaho National Engineering Laboratory, employed three 0.97-m long pressurized water reactor type fuel rods, fabricated from previously irradiated zircaloy-4 cladding and one similar rod fabricated from unirradiated cladding. The objectives of the test were to evaluate the influence of simulated fission products, cladding irradiation damage, and fuel rod internal pressure on pellet-cladding interaction during a power ramp and on fuel rod behavior during film boiling operation. The four rods were subjected to a preconditioning period, a power ramp to an average fuel rod peak power of 65 kW/m, and steady state operation for one hour at a coolant mass flux of 4880 kg/s-m 2 for each rod. After a flow reduction to 1800 kg/s-m 2 , film boiling occurred on one rod. Additional flow reductions to 970 kg/s-m 2 produced film boiling on the three remaining fuel rods. Maximum time in film boiling was 80s. The rod having the highest initial internal pressure (8.3 MPa) failed 10s after the onset of film boiling. A second rod failed about 90s after reactor shutdown. The report contains a description of the experiment, the test conduct, test results, and results from the preliminary postirradiation examination. Calculations using a transient fuel rod behavior code are compared with the test results

  5. Learning and Overnight Retention in Declarative Memory in Specific Language Impairment

    Science.gov (United States)

    Lukåcs, Ágnes; Kemény, Ferenc; Lum, Jarrad A. G.; Ullman, Michael T.

    2017-01-01

    We examined learning and retention in nonverbal and verbal declarative memory in Hungarian children with (n = 21) and without (n = 21) SLI. Recognition memory was tested both 10 minutes and one day after encoding. On nonverbal items, only the children with SLI improved overnight, with no resulting group differences in performance. In the verbal domain, the children with SLI consistently showed worse performance than the typically-developing children, but the two groups showed similar overnight changes. The findings suggest the possibility of spared or even enhanced declarative memory consolidation in SLI. PMID:28046095

  6. Retention of Economics Principles by Undergraduates on Alternative Curricular Structures

    Science.gov (United States)

    Johnson, Daniel K. N.; Lybecker, Kristina M.; Taylor, Corrine H.

    2011-01-01

    The authors investigated whether the curricular structure of an economics course (semester, trimester, or compressed block schedule) has an effect on an undergraduate's subsequent retention of course material, while controlling for other relevant differences. They tested separately for theoretical or process comprehension and for graphical


  7. The predictive ability of different customer feedback metrics for retention

    NARCIS (Netherlands)

    de Haan, Evert; Verhoef, Peter C.; Wiesel, Thorsten

    This study systematically compares different customer feedback metrics (CFMs) - namely customer satisfaction, the Net Promoter Score, and the Customer Effort Score - to test their ability to predict retention across a wide range of industries. We classify the CFMs according to a time focus (past,

  8. Rapid measurement of indocyanine green retention by pulse spectrophotometry: a validation study in 70 patients with Child-Pugh A cirrhosis before hepatectomy for hepatocellular carcinoma.

    Science.gov (United States)

    Cheung, Tan To; Chan, See Ching; Chok, Kenneth S H; Chan, Albert C Y; Yu, Wan Ching; Poon, Ronnie T P; Lo, Chung Mau; Fan, Sheung Tat

    2012-06-01

    The indocyanine green (ICG) retention test is the most popular liver function test for selecting patients for major hepatectomy. Traditionally, it is done using spectrophotometry with serial blood sampling. The newly-developed pulse spectrophotometry is a faster alternative, but its accuracy on Child-Pugh A cirrhotic patients undergoing hepatectomy for hepatocellular carcinoma has not been well documented. This study aimed to assess the accuracy of the LiMON(Âź), one of the pulse spectrophotometry systems, in measuring preoperative ICG retention in these patients and to devise an easy formula for conversion of the results so that they can be compared with classical literature records where ICG retention was measured by the traditional method. We measured the liver function of 70 Child-Pugh A cirrhotic patients before hepatectomy for hepatocellular carcinoma from September 2008 to January 2009. ICG retention at 15 minutes measured by traditional spectrophotometry (ICGR15) was compared with ICG retention at 15 minutes measured by the LiMON (ICGR15(L)). The median ICGR15 was 14.7% (5.6%-32%) and the median ICGR15(L) was 10.4% (1.2%-28%). The mean difference between them was -4.3606. There was a strong correlation between ICGR15 and ICGR15(L) (correlation coefficient, 0.844; 95% confidence interval, 0.762-0.899). The following formula was devised: ICGR15=1.16XICGR15(L)+2.73. The LiMON provides a fast and repeatable way to measure ICG retention at 15 minutes, but with constant underestimation of the real value. Therefore, when comparing results obtained by traditional spectrophotometry and the LiMON, adjustment of results from the latter is necessary, and this can be done with a simple mathematical calculation using the above formula.

  9. Retention of gaseous fission products by pure and modified activated carbon

    International Nuclear Information System (INIS)

    Wilhelmova, L.; Cejnar, F.

    1975-01-01

    The results are reported of research into Czechoslovak-made activated carbon Desorex DB-2 and Supersorbon HS-1 and their retention properties. Krypton, xenon and helium of spectral purity were used in the investigation. The effect of surface impregnation was also studied on the retention efficiency of the activated carbon. It was found that the impregnation with alkali metal fluorides, such as RbF and CsF favourably affected the retention properties of the activated carbon as concerns gaseous fission products. (L.O.)

  10. Retention of Basic Life Support in Laypeople: Mastery Learning vs. Time-based Education.

    Science.gov (United States)

    Boet, Sylvain; Bould, M Dylan; Pigford, Ashlee-Ann; Rössler, Bernhard; Nambyiah, Pratheeban; Li, Qi; Bunting, Alexandra; Schebesta, Karl

    2017-01-01

    To compare the effectiveness of a mastery learning (ML) versus a time-based (TB) BLS course for the acquisition and retention of BLS knowledge and skills in laypeople. After ethics approval, laypeople were randomized to a ML or TB BLS course based on the American Heart Association (AHA) Heartsaver course. In the ML group, subjects practiced and received feedback at six BLS stations until they reached a pre-determined level of performance. The TB group received a standard AHA six-station BLS course. All participants took the standard in-course BLS skills test at the end of their course. BLS skills and knowledge were tested using a high-fidelity scenario and knowledge questionnaire upon course completion (immediate post-test) and after four months (retention test). Video recorded scenarios were assessed by two blinded, independent raters using the AHA skills checklist. Forty-three subjects were included in analysis (23ML;20TB). For primary outcome, subjects' performance did not change after four months, regardless of the teaching modality (TB from (median[IQR]) 8.0[6.125;8.375] to 8.5[5.625;9.0] vs. ML from 8.0[7.0;9.0] to 7.0[6.0;8.0], p = 0.12 for test phase, p = 0.21 for interaction between effect of teaching modality and test phase). For secondary outcomes, subjects acquired knowledge between pre- and immediate post-tests (p < 0.005), and partially retained the acquired knowledge up to four months (p < 0.005) despite a decrease between immediate post-test and retention test (p = 0.009), irrespectively of the group (p = 0.59) (TB from 63.3[48.3;73.3] to 93.3[81.7;100.0] and then 93.3[81.7;93.3] vs. ML from 60.0[46.7;66.7] to 93.3[80.0;100.0] and then 80.0[73.3;93.3]). Regardless of the group after 4 months, chest compression depth improved (TB from 39.0[35.0;46.0] to 48.5[40.25;58.0] vs. ML from 40.0[37.0;47.0] to 45.0[37.0;52.0]; p = 0.012), but not the rate (TB from 118.0[114.0;125.0] to 120.5[113.0;129.5] vs. ML from 119.0[113.0;130.0] to 123.0[102.0;132.0]; p

  11. Results of a Flipped Classroom Teaching Approach in Anesthesiology Residents.

    Science.gov (United States)

    Martinelli, Susan M; Chen, Fei; DiLorenzo, Amy N; Mayer, David C; Fairbanks, Stacy; Moran, Kenneth; Ku, Cindy; Mitchell, John D; Bowe, Edwin A; Royal, Kenneth D; Hendrickse, Adrian; VanDyke, Kenneth; Trawicki, Michael C; Rankin, Demicha; Guldan, George J; Hand, Will; Gallagher, Christopher; Jacob, Zvi; Zvara, David A; McEvoy, Matthew D; Schell, Randall M

    2017-08-01

    In a flipped classroom approach, learners view educational content prior to class and engage in active learning during didactic sessions. We hypothesized that a flipped classroom improves knowledge acquisition and retention for residents compared to traditional lecture, and that residents prefer this approach. We completed 2 iterations of a study in 2014 and 2015. Institutions were assigned to either flipped classroom or traditional lecture for 4 weekly sessions. The flipped classroom consisted of reviewing a 15-minute video, followed by 45-minute in-class interactive sessions with audience response questions, think-pair-share questions, and case discussions. The traditional lecture approach consisted of a 55-minute lecture given by faculty with 5 minutes for questions. Residents completed 3 knowledge tests (pretest, posttest, and 4-month retention) and surveys of their perceptions of the didactic sessions. A linear mixed model was used to compare the effect of both formats on knowledge acquisition and retention. Of 182 eligible postgraduate year 2 anesthesiology residents, 155 (85%) participated in the entire intervention, and 142 (78%) completed all tests. The flipped classroom approach improved knowledge retention after 4 months (adjusted mean = 6%; P  = .014; d  = 0.56), and residents preferred the flipped classroom (pre = 46%; post = 82%; P  flipped classroom approach to didactic education resulted in a small improvement in knowledge retention and was preferred by anesthesiology residents.

  12. Height, Relationship Satisfaction, Jealousy, and Mate Retention

    Directory of Open Access Journals (Sweden)

    Gayle Brewer

    2009-07-01

    Full Text Available Male height is associated with high mate value. In particular, tall men are perceived as more attractive, dominant and of a higher status than shorter rivals, resulting in a greater lifetime reproductive success. Female infidelity and relationship dissolution may therefore present a greater risk to short men. It was predicted that tall men would report greater relationship satisfaction and lower jealousy and mate retention behavior than short men. Ninety eight heterosexual men in a current romantic relationship completed a questionnaire. Both linear and quadratic relationships were found between male height and relationship satisfaction, cognitive and behavioral jealousy. Tall men reported greater relationship satisfaction and lower levels of cognitive or behavioral jealousy than short men. In addition, linear and quadratic relationships were found between male height and a number of mate retention behaviors. Tall and short men engaged in different mate retention behaviors. These findings are consistent with previous research conducted in this area detailing the greater attractiveness of tall men.

  13. Retention and topology of the bovine viral diarrhea virus glycoprotein E2.

    Science.gov (United States)

    Radtke, Christina; Tews, Birke Andrea

    2017-10-01

    Pestiviruses are enveloped viruses that bud intracellularly. They have three envelope glycoproteins, E rns , E1, and E2. E2 is the receptor binding protein and the main target for neutralizing antibodies. Both E rns and E2 are retained intracellularly. Here, E2 of the bovine viral diarrhea virus (BVDV) strain CP7 was used to study the membrane topology and intracellular localization of the protein. E2 is localized in the ER and there was no difference between E2 expressed alone or in the context of the viral polyprotein. The mature E2 protein was found to possess a single span transmembrane anchor. For the mapping of a retention signal CD72-E2 fusion proteins, as well as E2 alone were analysed. This confirmed the importance of the transmembrane domain and arginine 355 for intracellular retention, but also revealed a modulating effect on retention through the cytoplasmic tail of the E2 protein, especially through glutamine 370. Mutants with a strong impact on retention were tested in the viral context and we were able to rescue BVDV with certain mutations that in E2 alone impaired intracellular retention and lead to export of E2 to the cells surface.

  14. Enhancing nitrification at low temperature with zeolite in a mining operations retention pond

    Directory of Open Access Journals (Sweden)

    Misha eMiazga-Rodriguez

    2012-07-01

    Full Text Available Ammonium nitrate explosives are used in mining operations at Diavik Diamond Mines Inc. in the Northwest Territories, Canada. Residual nitrogen is washed into the mine pit and piped to a nearby retention pond where its removal is accomplished by microbial activity prior to a final water treatment step and release into the sub-Arctic lake, Lac de Gras. Microbial removal of ammonium in the retention pond is rapid during the brief ice-free summer, but often slows under ice cover that persists up to nine months of the year. The aluminosilicate mineral zeolite was tested as an additive to retention pond water to increase rates of ammonium removal at 4 °C. Water samples were collected across the length of the retention pond monthly over a year. The structure of the microbial community (bacteria, archaea, and eukarya, as determined by denaturing gradient gel electrophoresis of PCR-amplified small subunit ribosomal RNA genes, was more stable during cold months than during July-September, when there was a marked phytoplankton bloom. Of the ammonia-oxidizing community, only bacterial amoA genes were consistently detected. Zeolite (10 g was added to retention pond water (100 mL amended with 5 mM ammonium and incubated at 12 °C to encourage development of a nitrifying biofilm. The biofilm community was composed of different amoA phylotypes from those identified in gene clone libraries of native water samples. Zeolite biofilm was added to fresh water samples collected at different times of the year, resulting in a significant increase in laboratory measurements of potential nitrification activity at 4 °C. A significant positive correlation between the amount of zeolite biofilm and potential nitrification activity was observed; rates were unaffected in incubations containing 1-20 mM ammonium. Addition of zeolite to retention ponds in cold environments could effectively increase nitrification rates year round by concentrating active nitrifying biomass.

  15. Enhancing nitrification at low temperature with zeolite in a mining operations retention pond.

    Science.gov (United States)

    Miazga-Rodriguez, Misha; Han, Sukkyun; Yakiwchuk, Brian; Wei, Kai; English, Colleen; Bourn, Steven; Bohnert, Seth; Stein, Lisa Y

    2012-01-01

    Ammonium nitrate explosives are used in mining operations at Diavik Diamond Mines Inc. in the Northwest Territories, Canada. Residual nitrogen is washed into the mine pit and piped to a nearby retention pond where its removal is accomplished by microbial activity prior to a final water treatment step and release into the sub-Arctic lake, Lac de Gras. Microbial removal of ammonium in the retention pond is rapid during the brief ice-free summer, but often slows under ice cover that persists up to 9 months of the year. The aluminosilicate mineral zeolite was tested as an additive to retention pond water to increase rates of ammonium removal at 4°C. Water samples were collected across the length of the retention pond monthly over a year. The structure of the microbial community (bacteria, archaea, and eukarya), as determined by denaturing gradient gel electrophoresis of PCR-amplified small subunit ribosomal RNA genes, was more stable during cold months than during July-September, when there was a marked phytoplankton bloom. Of the ammonia-oxidizing community, only bacterial amoA genes were consistently detected. Zeolite (10 g) was added to retention pond water (100 mL) amended with 5 mM ammonium and incubated at 12°C to encourage development of a nitrifying biofilm. The biofilm community was composed of different amoA phylotypes from those identified in gene clone libraries of native water samples. Zeolite biofilm was added to fresh water samples collected at different times of the year, resulting in a significant increase in laboratory measurements of potential nitrification activity at 4°C. A significant positive correlation between the amount of zeolite biofilm and potential nitrification activity was observed; rates were unaffected in incubations containing 1-20 mM ammonium. Addition of zeolite to retention ponds in cold environments could effectively increase nitrification rates year-round by concentrating active nitrifying biomass.

  16. On the optimal design of risk retention in securitisation

    Directory of Open Access Journals (Sweden)

    Metin Kaptan

    2011-09-01

    Full Text Available This paper examines the optimal design of retention in securitisation, in order to maximize welfare of screening per unit of retention, assuming that screening is costly and that the bank intends to securitise its loans. In contrast to the focus of previous literature on tranche retention, we deviate from the constitutional mechanisms of tranche retention to present a pareto-optimal method of tranche retention. Unlike the current ad-hoc-regulations, we derive the optimal design of retention from a utility maximization problem. We show that the level of retention per tranche should be dependent on the rate of credit default, i.e. the higher the rate of default, the higher the optimal rate of retention required to provide an incentive to screen carefully. From this approach, it follows that the rate of retention per tranche should be higher, the higher the position within the ranking order of subordination. Accordingly, the efficiency of tranche retention can be enhanced, reducing the level of retention required to maintain a given level of screening-effort. This retention design entails a recovery of the bank’s equity capital, thereby increasing liquidity and lending capacities.

  17. Colloid and radionuclide retention mechanisms in fractured rock under near-natural flow conditions

    International Nuclear Information System (INIS)

    Delos, A.; Schaefer, T.; Geckeis, H.; Guimera, J.; Carrera, J.; Fanghaenel, T.

    2005-01-01

    Full text of publication follows: Experiments in fractured host rock (Grimsel Test Site, GTS, Switzerland) revealed that the colloid relevance for actinide migration is high due to the specific geochemical groundwater conditions [1]. However, even under such conditions it is found that retention of colloids and colloid-borne actinides becomes significant under near-natural groundwater flow rates (1-10 m/a) [2]. Underlying mechanisms of colloid and radionuclide retention are not well understood up to now. The present study co-funded by the NoE ACTINET-6 focuses on (i) the kinetics of actinide-colloid interactions and (ii) the relevance of matrix diffusion as a competition process to other retention mechanisms which affect the actinides behavior in fractured rock systems such as the Grimsel granodiorite. Colloid migration is studied with well defined model colloids as e.g. fluorescence dyed carboxylated polystyrene particles, and natural colloids extracted from bentonite (FEBEX) and from fracture filling material (GTS). In order to study the influence of matrix porosity on actinides migration, those experiments are performed in columns of well defined geometry filled with microporous unmodified silica spheres, porous ceramic material and natural fracture filling material from the GTS. The behaviour of actinides (Pu(IV) and Am(III)) sorbed onto bentonite colloids is investigated in column and batch experiments. All experiments are performed under anoxic conditions. Colloid characterization methods used in this study include the combination of photon correlation spectroscopy (PCS), laser-induced breakdown detection (LIBD), fluorimetry and field flow fractionation (FFF). Experimental results and their application to the parametrisation of reactive colloid transport models are discussed. [1] Geckeis H, Schaefer T, Hauser W, Rabung T, Missana T, Degueldre C, Moeri A, Eikenberg J, Fierz T, Alexander WR (2004) Results of the Colloid and Radionuclide Retention experiment

  18. Interventions to improve recruitment and retention in clinical trials: a survey and workshop to assess current practice and future priorities.

    Science.gov (United States)

    Bower, Peter; Brueton, Valerie; Gamble, Carrol; Treweek, Shaun; Smith, Catrin Tudur; Young, Bridget; Williamson, Paula

    2014-10-16

    Despite significant investment in infrastructure many trials continue to face challenges in recruitment and retention. We argue that insufficient focus has been placed on the development and testing of recruitment and retention interventions. In this current paper, we summarize existing reviews about interventions to improve recruitment and retention. We report survey data from Clinical Trials Units in the United Kingdom to indicate the range of interventions used by these units to encourage recruitment and retention. We present the views of participants in a recent workshop and a priority list of recruitment interventions for evaluation (determined by voting among workshop participants). We also discuss wider issues concerning the testing of recruitment interventions. Methods used to encourage recruitment and retention were categorized as: patient contact, patient convenience, support for recruiters, monitoring and systems, incentives, design, resources, and human factors. Interventions felt to merit investigation by respondents fell into three categories: training site staff, communication with patients, and incentives. Significant resources continue to be invested into clinical trials and other high quality studies, but recruitment remains a significant challenge. Adoption of innovative methods to develop, test, and implement recruitment interventions are required.

  19. The Effect of a Continuous Quality Improvement Intervention on Retention-In-Care at 6 Months Postpartum in a PMTCT Program in Northern Nigeria: Results of a Cluster Randomized Controlled Study.

    Science.gov (United States)

    Oyeledun, Bolanle; Phillips, Abimbola; Oronsaye, Frank; Alo, Oluwafemi David; Shaffer, Nathan; Osibo, Bamidele; Imarhiagbe, Collins; Ogirima, Francis; Ajibola, Abiola; Ezebuka, Obioma; Ojong-Etta, Bebia; Obi, Adaobi; Falade, John; Uthman, Adunbi Kareem; Famuyide, Busuyi; Odoh, Deborah; Becquet, Renaud

    2017-06-01

    Retention in care is critical for improving HIV-infected maternal outcomes and reducing vertical transmission. Health systems' interventions such as continuous quality improvement (CQI) may support health services to address factors that affect the delivery of HIV-related care and thereby influence rates of retention-in-care. We evaluated the effect of a CQI intervention on retention-in-care at 6 months postpartum of pregnant women and mothers living with HIV who had been started on lifelong antiretroviral treatment. Thirty-two health care facilities were randomized to either implement the intervention or not. We considered women fully retained in care when they attended the 6-month postpartum visit and did not miss any previous scheduled visit by more than 30 days. Five hundred eleven women living with HIV attending antenatal clinics at 26 facilities were included in the analysis. Median age at enrolment was 27 years and gestational age was 20 weeks. Seventy-one percent of women were seen at 6-month postpartum irrespective of missing any scheduled visit. However, 43% of women were fully retained at 6-month postpartum and did not miss any scheduled visit based on our stringent study definition of retention. There was no significant difference in retention at 6 months between the intervention and control arms [44% vs. 41%, relative risk: 1.08; 95% confidence interval (CI): 0.78 to 1.49]. Initiation of ARV prophylaxis among infants within 72 hours was not different by study arm (66.0% vs. 74.7%, relative risk = 0.95; 95% CI: 0.84 to 1.07) but rates of early infant testing at 4-6 weeks were higher in intervention sites (48.8% vs. 25.3%, adjusted relative risk: 1.76; 95% CI: 1.27 to 2.42). CQI as implemented in this study did not differ across study arms in the rates of retention. Several intervention design or implementation issues or other contextual constraints may explain the absence of effect.

  20. Effects of two retraining strategies on nursing students' acquisition and retention of BLS/AED skills: A cluster randomised trial.

    Science.gov (United States)

    Hernåndez-Padilla, José Manuel; Suthers, Fiona; Granero-Molina, José; Fernåndez-Sola, Cayetano

    2015-08-01

    To determine and compare the effects of two different retraining strategies on nursing students' acquisition and retention of BLS/AED skills. Nursing students (N = 177) from two European universities were randomly assigned to either an instructor-directed (IDG) or a student-directed (SDG) 4-h retraining session in BLS/AED. A multiple-choice questionnaire, the Cardiff Test, Laerdal SkillReporter(Ÿ) software and a self-efficacy scale were used to assess students' overall competency (knowledge, psychomotor skills and self-efficacy) in BLS/AED at pre-test, post-test and 3-month retention-test. GEE, chi-squared and McNemar tests were performed to examine statistical differences amongst groups across time. There was a significant increase in the proportion of students who achieved competency for all variables measuring knowledge, psychomotor skills and self-efficacy between pre-test and post-test in both groups (all p-valuesstudy demonstrated that using a student-directed strategy to retrain BLS/AED skills has resulted in a higher proportion of nursing students achieving and retaining competency in BLS/AED at three months when compared to an instructor-directed strategy. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Retention of first aid and basic life support skills in undergraduate medical students.

    Science.gov (United States)

    de Ruijter, Pim A; Biersteker, Heleen A; Biert, Jan; van Goor, Harry; Tan, Edward C

    2014-01-01

    Undergraduate medical students follow a compulsory first aid (FA) and basic life support (BLS) course. Retention of BLS seems poor and only little information is provided on the retention of FA skills. This study aims at evaluating 1- and 2-year retention of FA and BLS training in undergraduate medical students. One hundred and twenty students were randomly selected from first year (n=349) medical students who successfully followed a compulsory FA and BLS course. From these 120 students, 94 (78%) and 69 (58%) participated in retention tests of FA and BLS skills after 1 and 2 years, respectively. The assessment consisted of two FA stations and one BLS station. After 1 year, only 2% passed both FA and BLS stations and 68% failed both FA and BLS stations. After 2 years, 5% passed and 50% failed both FA and BLS stations. Despite the high failure rate at the stations, 90% adequately checked vital signs and started cardiopulmonary resuscitation appropriately. The long-term retention of FA and BLS skills after a compulsory course in the first year is poor. Adequate check of vital signs and commencing cardiopulmonary resuscitation retained longer.

  2. A comparative evaluation of the effect of dentin desensitizers on the retention of complete cast metal crowns

    Directory of Open Access Journals (Sweden)

    Saili M Chandavarkar

    2015-01-01

    Full Text Available Context: Desensitizers are used to reduce dentin hypersensitivity. They affect the surface texture of prepared dentin and may alter the retention of fixed restorations. Aims: The aim was to evaluate the effect of dentin desensitizers on the retention of complete cast metal crowns luted with glass ionomer cement. Subjects and Methods: Fifty freshly extracted human premolars were subjected to standardized tooth preparation (20° total convergence, 4 mm axial height with a computer numerically controlled machine. Individual cast metal crowns were fabricated from a base metal alloy. Dentin desensitizers included none (control, a glutaraldehyde (GLU based primer (Gluma desensitizer, casein phosphopeptide (CPP-amorphous calcium phosphate (ACP (GC Mousse, erbium, chromium: YSGG laser (Waterlase MD Turbo, Biolase and Pro-Argin (Colgate Sensitive Pro-Relief desensitizing polishing paste. After desensitization, crowns were luted with glass ionomer cement and kept for 48 h at 37°C in 100% relative humidity. The samples were tested using a universal testing machine by applying a load at a crosshead speed of 0.5 mm/min. Statistical Analysis Used: Statistical analysis included One-way ANOVA, followed by the Scheffe post-hoc test with P < 0.05. Results: All dentin desensitizers showed significantly different values: Pro-Argin (4.10 Megapascals [Mpa] < CPP-ACP (4.01 mpa < GLU based primer (3.87 Mpa < Virgin dentin (3.65 Mpa < LASER (3.37 Mpa. Conclusions : On comparing the effect of prepared virgin dentin, GLU based primer, CPP-ACP, LASER and Pro-Argin on the retention of complete cast metal crowns luted with glass ionomer cement on prepared teeth, it can be concluded that Pro-Argin and CPP-ACP showed the best retention in this in vitro study.

  3. Retention of Pictorial and Verbal Content of A Text with Illustrations

    Science.gov (United States)

    Peeck, J.

    1974-01-01

    Questioning why illustrated text is commonly used for children in the absence of significant proof of its usefulness, the present author undertook a study to measure fourth graders' retention of three variations of a story book text. Results indicate illustrations have several effects on retention. (BJG)

  4. Validation of Code ASTEC with LIVE-L1 Experimental Results

    International Nuclear Information System (INIS)

    Bachrata, Andrea

    2008-01-01

    The severe accidents with core melting are considered at the design stage of project at Generation 3+ of Nuclear Power Plants (NPP). Moreover, there is an effort to apply the severe accident management to the operated NPP. The one of main goals of severe accidents mitigation is corium localization and stabilization. The two strategies that fulfil this requirement are: the in-vessel retention (e.g. AP-600, AP- 1000) and the ex-vessel retention (e.g. EPR). To study the scenario of in-vessel retention, a large experimental program and the integrated codes have been developed. The LIVE-L1 experimental facility studied the formation of melt pools and the melt accumulation in the lower head using different cooling conditions. Nowadays, a new European computer code ASTEC is being developed jointly in France and Germany. One of the important steps in ASTEC development in the area of in-vessel retention of corium is its validation with LIVE-L1 experimental results. Details of the experiment are reported. Results of the ASTEC (module DIVA) application to the analysis of the test are presented. (author)

  5. Enhanced Personal Contact With HIV Patients Improves Retention in Primary Care: A Randomized Trial in 6 US HIV Clinics

    OpenAIRE

    Gardner, Lytt I.; Giordano, Thomas P.; Marks, Gary; Wilson, Tracey E.; Craw, Jason A.; Drainoni, Mari-Lynn; Keruly, Jeanne C.; Rodriguez, Allan E.; Malitz, Faye; Moore, Richard D.; Bradley-Springer, Lucy A.; Holman, Susan; Rose, Charles E.; Girde, Sonali; Sullivan, Meg

    2014-01-01

    The intervention tested in the Retention in Care Study demonstrated improvement in retention in human immunodeficiency virus care. Enhanced personal contact with or without additional behavioral skills training significantly improved visit constancy and visit adherence over 12 months.

  6. Particle retention during long discharges in Tore Supra and JET

    International Nuclear Information System (INIS)

    Loarer, T.; Tsitrone, E.; Brosset, C.; Bucalossi, J.; Gunn, J.; Joffrin, E.; Monier-Garbet, P.; Pegourie, B.; Thomas, P.; Lomas, P.; Ongena, J.

    2003-01-01

    The particle balances and the associated particle retentions for the long discharge experiments performed in Tore-Supra and for the L and H mode discharges carried out in JET are reported in this paper. From the reported experiments, the same particle retention behaviors are observed in Tore-Supra and JET in spite of the differences between the plasma geometry and the confinement mode (respectively limiter L-mode and divertor H-mode). A particle retention up to 70-80% of Γ(puff) for the larger gas injection has been obtained in JET. The particle retention behavior observed with the gas puff appears to be strongly dominant in the particle retention process. Indeed, no influence has been noticed from the active pumping, the saturation of the recycling area (0.4 D/C), the precedent discharges history (in terms of total 'particles retained' in the vessel) and even from the disruptions (conditioning). Also, the outgassing between discharges becomes negligible in terms of particle recovering when Γ(puff) and/or the discharge duration are increased. Finally, neither the edge localized modes (ELMs type-I or III) nor the disruptions modify the reported behaviour. For ITER, the particle retention is strictly limited and from the presented results it seems that strong gas injection should be avoided. (A.C.)

  7. Mate Value Discrepancy and Mate Retention Behaviors of Self and Partner.

    Science.gov (United States)

    Sela, Yael; Mogilski, Justin K; Shackelford, Todd K; Zeigler-Hill, Virgil; Fink, Bernhard

    2017-10-01

    This study investigated the relationship between perceived mate value discrepancy (i.e., the difference between an individual's mate value and their partner's mate value) and perceived frequency of mate retention performed by an individual relative to his or her partner. In two studies, participants in long-term, exclusive, sexual, heterosexual relationships reported their own, and their partner's, mate value and mate retention. Samples included 899 community members (Study 1) and 941 students and community members (Study 2). In Study 1, we documented that individuals with higher self-perceived short-term mate value, and who perceive their partner to have lower (vs. higher) short-term mate value, perform less frequent Benefit-Provisioning mate retention, controlling for the partner's Benefit-Provisioning mate retention. In Study 2, we documented that individuals who perceive that they could less easily replace their partner, and who perceive their partner could more (vs. less) easily replace them, perform more frequent mate retention (Benefit-Provisioning and Cost-Inflicting), controlling for the partner's mate retention. These results highlight the importance of assessing perceived discrepancies in mate value (notably, regarding the replaceability of self and partner with another long-term mate) and perceived mate retention behaviors of self, relative to partner, between men and women in long-term relationships. © 2016 Wiley Periodicals, Inc.

  8. Retention of actinide and fission products by poly-mineral solid phases

    International Nuclear Information System (INIS)

    Peynet, Vincent

    2003-01-01

    This research thesis first reports available knowledge on reactivity of mineral surfaces (notably the thermodynamic modelling of their retention properties) and discusses the different approaches proposed in the literature regarding the prediction of retention of an element on an adsorbent mixing. It also proposes a synthesis of publications on retention properties of montmorillonite, goethite and calcite with respect to elements with high or very low concentrations. Then, the author reports a characterization of solids in terms of ion exchanger theory. Results are used for traces of caesium, americium and selenium. He finally reports measurement results of traces of elements by montmorillonite / goethite and montmorillonite / calcite binary mixings, or by montmorillonite / goethite / calcite ternary mixings

  9. Influence of the mechanical properties of resilient denture liners on the retention of overdenture attachments.

    Science.gov (United States)

    Kubo, Keitaro; Koike, Takashi; Ueda, Takayuki; Sakurai, Kaoru

    2018-03-15

    Information is lacking about the selection criteria for silicone resilient denture liners applied as a matrix material for attachments on overdentures. The purpose of this in vitro study was to investigate the mechanical properties of silicone resilient denture liners and their influence on the initial retention force of overdenture attachments and the reduction in retention force over time. Nine types of silicone resilient denture liner were injected and fixed to the matrix section of an experimental denture base. They were then fitted to an epoxy resin model that simulated the residual ridge with a patrix ball attachment (n=10). The retention force of the denture was measured with a digital force gauge, and the maximum force of traction (N) was regarded as the initial retention force. The retention force reduction (N) after repeated insertion and removal (n=5) was calculated by subtracting the retention force after 3348 cycles (3-year simulated insertion and removal) from the initial retention force. The intaglio of the matrix was observed with a scanning electron microscope (SEM) before and after the 3348 cycles. Four mechanical properties (hardness, strain-in-compression, tensile strength, and arithmetic mean roughness) of the resilient denture liners were measured. One-way ANOVA of the initial retention force of each lining material was performed, followed by the Scheffe test (α=.05). Pearson correlation analysis was used (α=.05) to analyze correlations of the initial retention force with the retention force reduction after insertion and removal and the mechanical properties of each material. Multiple regression analysis with the stepwise method extracted the initial retention force and the retention force reduction as dependent variables, and the resilient denture liner mechanical properties as explanatory variables (α=.05). The initial retention force of the resilient denture liners was 1.3 to 5.4 N. Multiple comparisons showed significant differences in

  10. In Situ Vitrification preliminary results from the first large-scale radioactive test

    International Nuclear Information System (INIS)

    Buelt, J.L.; Westsik, J.H.

    1988-01-01

    The first large-scale radioactive test (LSRT) of In Situ Vitrification (ISV) has been completed. In Situ Vitrification is a process whereby joule heating immobilizes contaminated soil in place by converting it to a durable glass and crystalline waste form. The LSRT was conducted at an actual transuranic contaminated soil site on the Department of Energy's Hanford Site. The test had two objectives: 1) determine large-scale processing performance and 2) produce a waste form that can be fully evaluated as a potential technique for the final disposal of transuranic-contaminated soil sites at Hanford. This accomplishment has provided technical data to evaluate the ISV process for its potential in the final disposition of transuranic-contaminated soil sites at Hanford. The LSRT was completed in June 1987 after 295 hours of operation and 460 MWh of electrical energy dissipated to the molten soil. This resulted in a minimum of a 450-t block of vitrified soil extending to a depth of 7.3m (24 ft). The primary contaminants vitrified during the demonstration were Pu and Am transuranics, but also included up to 26,000 ppm fluorides. Preliminary data show that their retention in the vitrified product exceeded predictions meaning that fewer contaminants needed to be removed from the gaseous effluents by the processing equipment. The gaseous effluents were contained and treated throughout the run; that is, no radioactive or hazardous chemical releases were detected

  11. Charge retention in scaled SONOS nonvolatile semiconductor memory devices—Modeling and characterization

    Science.gov (United States)

    Hu, Yin; White, Marvin H.

    1993-10-01

    A new analytical model is developed to investigate the influence of the charge loss processes in the retention mode of the SONOS NVSM device. The model considers charge loss by the following processes: (1) electron back-tunneling from the nitride traps to the Si conduction band, (2) electron back-tunneling from the nitride traps to the Si/SiO 2 interface traps and (3) hole injection from the Si valence band to the nitride traps. An amphoteric trap charge distribution is used in this model. The new charge retention model predicts that process (1) determines the short term retention, while processes (2) and (3) determine the long term retention. Good agreement has been reached between the results of analytical calculations and the experimental retention data on both surface channel and buried channel SONOS devices.

  12. Predicting subscriber dissatisfaction and improving retention in the wireless telecommunications industry.

    Science.gov (United States)

    Mozer, M C; Wolniewicz, R; Grimes, D B; Johnson, E; Kaushansky, H

    2000-01-01

    Competition in the wireless telecommunications industry is fierce. To maintain profitability, wireless carriers must control churn, which is the loss of subscribers who switch from one carrier to another.We explore techniques from statistical machine learning to predict churn and, based on these predictions, to determine what incentives should be offered to subscribers to improve retention and maximize profitability to the carrier. The techniques include logit regression, decision trees, neural networks, and boosting. Our experiments are based on a database of nearly 47,000 U.S. domestic subscribers and includes information about their usage, billing, credit, application, and complaint history. Our experiments show that under a wide variety of assumptions concerning the cost of intervention and the retention rate resulting from intervention, using predictive techniques to identify potential churners and offering incentives can yield significant savings to a carrier. We also show the importance of a data representation crafted by domain experts. Finally, we report on a real-world test of the techniques that validate our simulation experiments.

  13. Effects of abutment diameter, luting agent type, and re-cementation on the retention of implant-supported CAD/CAM metal copings over short abutments

    Science.gov (United States)

    Safari, Sina; Amini, Parviz; Yaghmaei, Kaveh

    2018-01-01

    PURPOSE The aim of this study was to evaluate the effects of abutment diameter, cement type, and re-cementation on the retention of implant-supported CAD/CAM metal copings over short abutments. MATERIALS AND METHODS Sixty abutments with two different diameters, the height of which was reduced to 3 mm, were vertically mounted in acrylic resin blocks with matching implant analogues. The specimens were divided into 2 diameter groups: 4.5 mm and 5.5 mm (n=30). For each abutment a CAD/CAM metal coping was manufactured, with an occlusal loop. Each group was sub-divided into 3 sub-groups (n=10). In each subgroup, a different cement type was used: resin-modified glass-ionomer, resin cement and zinc-oxide-eugenol. After incubation and thermocycling, the removal force was measured using a universal testing machine at a cross-head speed of 0.5 mm/min. In zinc-oxide-eugenol group, after removal of the coping, the cement remnants were completely cleaned and the copings were re-cemented with resin cement and re-tested. Two-way ANOVA, post hoc Tukey tests, and paired t-test were used to analyze data (α=.05). RESULTS The highest pulling force was registered in the resin cement group (414.8 N), followed by the re-cementation group (380.5 N). Increasing the diameter improved the retention significantly (P=.006). The difference in retention between the cemented and recemented copings was not statistically significant (P=.40). CONCLUSION Resin cement provided retention almost twice as strong as that of the RMGI. Increasing the abutment diameter improved retention significantly. Re-cementation with resin cement did not exhibit any difference from the initial cementation with resin cement. PMID:29503708

  14. A Study on Employee Retention Techniques

    OpenAIRE

    Savarimuthu, Dr. A; Hemalatha, N.

    2013-01-01

    The objective of perusing this study is to assess the level of satisfaction of employee retention techniques at GB Engineering Enterprises PVT Limited., Trichy.This study gains significance because of employee retention techniques can be approached from various angles. It is desirable state of existence involving retention strategies generally fall in to one of four categories salary, working conditions, job enrichment and education. These four elements together constitute. The structure of e...

  15. Chemical adhesion rather than mechanical retention enhances resin bond durability of a dental glass-ceramic with leucite crystallites

    International Nuclear Information System (INIS)

    Meng, X F; Yoshida, K; Gu, N

    2010-01-01

    This study aims to evaluate the effect of chemical adhesion by a silane coupler and mechanical retention by hydrofluoric acid (HFA) etching on the bond durability of resin to a dental glass ceramic with leucite crystallites. Half of the ceramic plates were etched with 4.8% HFA (HFA group) for 60 s, and the other half were not treated (NoHFA group). The scale of their surface roughness and rough area was measured by a 3D laser scanning microscope. These plates then received one of the following two bond procedures to form four bond test groups: HFA/cement, NoHFA/cement, HFA/silane/cement and NoHFA/silane/cement. The associated micro-shear bond strength and bond failure modes were tested after 0 and 30 000 thermal water bath cycles. Four different silane/cement systems (Monobond S/Variolink II, GC Ceramic Primer/Linkmax HV, Clearfil Ceramic Primer/Clearfil Esthetic Cement and Porcelain Liner M/SuperBond C and B) were used. The data for each silane/cement system were analyzed by three-way ANOVA. HFA treatment significantly increased the surface R a and R y values and the rough area of the ceramic plates compared with NoHFA treatment. After 30 000 thermal water bath cycles, the bond strength of all the test groups except the HFA/Linkmax HV group was significantly reduced, while the HFA/Linkmax HV group showed only adhesive interface failure. The other HFA/cement groups and all NoHFA/cement groups lost bond strength completely, and all NoHFA/silane/cement groups with chemical adhesion had significantly higher bond strength and more ceramic cohesive failures than the respective HFA/cement groups with mechanical retention. The result of the HFA/silane/cement groups with both chemical adhesion and mechanical retention revealed that HFA treatment could enhance the bond durability of resin/silanized glass ceramics, which might result from the increase of the chemical adhesion area on the ceramic rough surface and subsequently reduced degradation speed of the silane coupler

  16. Effect of biochar amendment on nitrate retention in a silty clay loam soil

    Directory of Open Access Journals (Sweden)

    Angela Libutti

    2016-08-01

    Full Text Available Biochar incorporation into agricultural soils has been proposed as a strategy to decrease nutrient leaching. The present study was designed to assess the effect of biochar on nitrate retention in a silty clay loam soil. Biochar obtained from the pyrogasification of fir wood chips was applied to soil and tested in a range of laboratory sorption experiments. Four soil treatments were considered: soil only (control, soil with 2, 4 and 8% of biochar by mass. The Freundlich sorption isotherm model was used to fit the adsorbed amount of nitrate in the soil-biochar mixtures. The model performed very well in interpreting the experimental data according to a general linear regression (analysis of co-variance statistical approach. Nitrate retention in the soilbiochar mixtures was always higher than control, regardless the NO3 – concentration in the range of 0-400 mg L–1. Different sorption capacities and intensities were detected depending on the biochar application rate. The highest adsorption capacity was observed in the soils added with 2 and 4% of biochar, respectively. From the results obtained is possible to infer that nitrate retention is higher at lower biochar addition rate to soil (2 and 4% and at lower nitrate concentration in the soil water solution. These preliminary laboratory results suggest that biochar addition to a typical Mediterranean agricultural soil could be an effective management option to mitigate nitrate leaching.

  17. Modelling of long term nitrogen retention in surface waters

    Science.gov (United States)

    Halbfaß, S.; Gebel, M.; BĂŒrger, S.

    2010-12-01

    In order to derive measures to reduce nutrient loadings into waters in Saxony, we calculated nitrogen inputs with the model STOFFBILANZ on the regional scale. Thereby we have to compare our modelling results to measured loadings at the river basin outlets, considering long term nutrient retention in surface waters. The most important mechanism of nitrogen retention is the denitrification in the contact zone of water and sediment, being controlled by hydraulic and micro-biological processes. Retention capacity is derived on the basis of the nutrient spiralling concept, using water residence time (hydraulic aspect) and time-specific N-uptake by microorganisms (biological aspect). Short time related processes of mobilization and immobilization are neglected, because they are of minor importance for the derivation of measures on the regional scale.

  18. Computer game-based and traditional learning method: a comparison regarding students' knowledge retention.

    Science.gov (United States)

    Rondon, Silmara; Sassi, Fernanda Chiarion; Furquim de Andrade, Claudia Regina

    2013-02-25

    Educational computer games are examples of computer-assisted learning objects, representing an educational strategy of growing interest. Given the changes in the digital world over the last decades, students of the current generation expect technology to be used in advancing their learning requiring a need to change traditional passive learning methodologies to an active multisensory experimental learning methodology. The objective of this study was to compare a computer game-based learning method with a traditional learning method, regarding learning gains and knowledge retention, as means of teaching head and neck Anatomy and Physiology to Speech-Language and Hearing pathology undergraduate students. Students were randomized to participate to one of the learning methods and the data analyst was blinded to which method of learning the students had received. Students' prior knowledge (i.e. before undergoing the learning method), short-term knowledge retention and long-term knowledge retention (i.e. six months after undergoing the learning method) were assessed with a multiple choice questionnaire. Students' performance was compared considering the three moments of assessment for both for the mean total score and for separated mean scores for Anatomy questions and for Physiology questions. Students that received the game-based method performed better in the pos-test assessment only when considering the Anatomy questions section. Students that received the traditional lecture performed better in both post-test and long-term post-test when considering the Anatomy and Physiology questions. The game-based learning method is comparable to the traditional learning method in general and in short-term gains, while the traditional lecture still seems to be more effective to improve students' short and long-term knowledge retention.

  19. Factors affecting the initial adhesion and retention of the plant pathogen Xylella fastidiosa in the foregut of an insect vector.

    Science.gov (United States)

    Killiny, Nabil; Almeida, Rodrigo P P

    2014-01-01

    Vector transmission of bacterial plant pathogens involves three steps: pathogen acquisition from an infected host, retention within the vector, and inoculation of cells into susceptible tissue of an uninfected plant. In this study, a combination of plant and artificial diet systems were used to determine the importance of several genes on the initial adhesion and retention of the bacterium Xylella fastidiosa to an efficient insect vector. Mutant strains included fimbrial (fimA and pilB) and afimbrial (hxfA and hxfB) adhesins and three loci involved in regulatory systems (rpfF, rpfC, and cgsA). Transmission assays with variable retention time indicated that HxfA and HxfB were primarily important for early adhesion to vectors, while FimA was necessary for both adhesion and retention. The long pilus protein PilB was not deficient in initial adhesion but may be important for retention. Genes upregulated under the control of rpfF are important for both initial adhesion and retention, as transmission rates of this mutant strain were initially low and decreased over time, while disruption of rpfC and cgsA yielded trends similar to that shown by the wild-type control. Because induction of an X. fastidiosa transmissible state requires pectin, a series of experiments were used to test the roles of a polygalacturonase (pglA) and the pectin and galacturonic acid carbohydrates on the transmission of X. fastidiosa. Results show that galacturonic acid, or PglA activity breaking pectin into its major subunit (galacturonic acid), is required for X. fastidiosa vector transmission using an artificial diet system. This study shows that early adhesion and retention of X. fastidiosa are mediated by different factors. It also illustrates that the interpretation of results of vector transmission experiments, in the context of vector-pathogen interaction studies, is highly dependent on experimental design.

  20. MITG test procedure and results

    International Nuclear Information System (INIS)

    Eck, M.E.; Mukunda, M.

    1983-01-01

    Elements and modules for Radioisotope Thermoelectric Generator have been performance tested since the inception of the RTG program. These test articles seldom resembled flight hardware and often lacked adequate diagnostic instrumentation. Because of this, performance problems were not identified in the early stage of program development. The lack of test data in an unexpected area often hampered the development of a problem solution. A procedure for conducting the MITG Test was developed in an effort to obtain data in a systematic, unambiguous manner. This procedure required the development of extensive data acquisition software and test automation. The development of a facility to implement the test procedure, the facility hardware and software requirements, and the results of the MITG testing are the subject of this paper

  1. Evaluation of Retention in Methadone Treatment in Patients Attending Baharan Hospital Clinic in Zahedan City

    Directory of Open Access Journals (Sweden)

    M.D. Mohebi

    2015-04-01

    Full Text Available Introduction & Objectives: Substance abuse and opioid dependency refers to hazardous use of psychoactive substance .Prevention and treatment of opiate dependence has not been success-ful. Most effective drug in agonist treatment of opiates is methadone maintenance therapy (MMT.But the lack of cooperation of addicts in methadone maintenance therapy has always been a big problem to continue. The purpose of this study is to investigate the retention in the MMT. Materials & Methods: This historical cohort study analyzed the medical records of patients of Baharan hospital in Zahedan. All 912 cases of methadone maintenance clinic of Baharan hos-pital in Zahedan 2011-2012 were studied and the data were analyzed using SPSS. Tables and indexes were analyzed by the Chi-square test and survival curves were plotted using Kaplan–Meier method and analyzed by Log-Rank test. Results: This study reviewed records from 912 patients with a mean age of 34.67% and stan-dard deviation of 10.88 and the range of 15-86 years. 735 were male and 177 ware female. 1-moth retention rate was 71%, 3 months was 59%, 6 months was 47%, 1 year was 30% and 2 years was 17%. Kaplan-Meier median survival time of 8 months was estimated by relation-ship. Doses higher than 60 mg/d of methadone was associated with increased survival on MMT. Conclusion: Age increase, increase of employment time, increasing of the duration of drug abuse, increasing the daily dose of methadone, oral substance abuse increased retention rate and heroin abuse and smoking were associated with decrease retention rate of methadone maintenance therapy. So, with an emphasis on each of these factors effective steps can be taken to improve the cooperation of patients in MMT. (Sci J Hamadan Univ Med Sci 2015; 22 (1:30-36

  2. Content and retention evaluation of an audiovisual patient-education program on bronchodilators.

    Science.gov (United States)

    Darr, M S; Self, T H; Ryan, M R; Vanderbush, R E; Boswell, R L

    1981-05-01

    A study was conducted to: (1) evaluate the effect of a slide-tape program on patients' short-term and long-term knowledge about their bronchodilator medications; and (2) determine it any differences exist in learning or retention patterns for different content areas of drug information. The knowledge of 30 patients was measured using a randomized sequence of three comparable 15-question tests. The first test was given before the slide-tape program was presented, the second test within 24 hours, and the last test one to six months (mean = 2.8 months) later. Scores attained on the first posttest were significantly higher (p less than 0.001) than pretest scores. Learning differences among drug-information-content areas were not evidenced on the first posttest. No significant difference was demonstrated between scores on pretest and last posttest (p = 0.100). However, retention patterns among content areas were found to differ significantly (p less than 0.05). Carefully designed audiovisual programs can impart drug information to patients. Medication counseling should be repeated at appropriate opportunities because patients lose drug knowledge over time.

  3. The Influence of a Humectant on the Retention by Humans of Solanesol from Cigarette Smoke (Part 2, Glycerin

    Directory of Open Access Journals (Sweden)

    Moldoveanu SC

    2014-12-01

    Full Text Available Two common humectants are used as additives in the cigarette manufacturing process, propylene glycol (PG and glycerin. The humectants may influence the deposition of cigarette smoke in the human respiratory tract by affecting the hygroscopic properties and growth of smoke particles. This study examines the influence of glycerin addition on the retention of solanesol by smokers. The influence of PG addition has been previously reported (7. The first cigarette used in the study (control was a commercially available brand containing no additives in the blend (with a measured level of glycerin of 0.19%. The other cigarette (test had an identical tobacco blend to the control, but had 2.3% added glycerin. The construction of the cigarette with 2.3% glycerin (test was selected to match as closely as possible the ‘tar’ (as measured by Federal Trade Commission regimen, pressure drop (open and closed, and nicotine level of the commercial cigarette (control. Twelve smokers evaluated both products. The sample collection was performed using three cigarettes smoked within one hour. Each human subject smoked the control cigarette and then the test cigarette in two separate sessions. The exhaled smoke was collected using a vacuum assisted procedure designed to avoid strain in exhaling, and solanesol was analyzed using an high performance liquid chromatography (HPLC technique. The cigarette butts from the smokers were collected and also analyzed for solanesol. The results obtained for the cigarette butts from the smokers were used to calculate the level of solanesol in the smoke delivered to the human subject, based on calibration curves. These curves were generated separately by analyzing the solanesol in smoke and in the cigarette butts obtained by machine smoking under different puffing regimes. Knowing the levels of delivered amount of solanesol and that in the exhaled smoke it was possible to calculate the retention of this compound from mainstream

  4. Fission-product retention in HTGR fuels

    International Nuclear Information System (INIS)

    Homan, F.J.; Kania, M.J.; Tiegs, T.N.

    1982-01-01

    Retention data for gaseous and metallic fission products are presented for both Triso-coated and Biso-coated HTGR fuel particles. Performance trends are established that relate fission product retention to operating parameters, such as temperature, burnup, and neutron exposure. It is concluded that Biso-coated particles are not adequately retentive of fission gas or metallic cesium, and Triso-coated particles which retain cesium still lose silver. Design implications related to these performance trends are identified and discussed

  5. A modified technique for retention of orbital prosthesis

    Directory of Open Access Journals (Sweden)

    Sameera R Shaikh

    2011-01-01

    Full Text Available An orbital defect (congenital or acquired causes severe facial asymmetry and disfigurement, which results in psychological and social disturbances to the patient. It becomes a challenging task for a maxillofacial prosthodontist to fabricate a prosthesis that replicates the healthy side of the face. Success of the prosthesis depends primarily on satisfactory retention of the same. This clinical report illustrates rehabilitation of a patient with an orbital defect by fabricating a hollow orbital prosthesis, utilizing anatomical undercuts for retention using an acrylic resin template relined by a resilient denture liner.

  6. Evaluation of gingival fiber retention technique on the treatment of patients with chronic periodontitis: A comparative study

    Directory of Open Access Journals (Sweden)

    Pooja Palwankar

    2011-01-01

    Full Text Available The destructive action of the chronic periodontitis on the periodontal tissues has provided a continuous challenge to the dental profession to develop better methods to achieve repair of the recession regions and even regeneration of post periodontal tissues. Aims: To assess the effect of periodontal muco-periostal flap surgery with gingival fiber retention technique on minimizing the post surgical recession. Materials and Methods: The sample for the study comprised of 20 patients. The criteria for selection included patients with moderate periodontitis, with minimum recession in the anterior teeth, with adequate width of the attached gingiva, and with no traumatic occlusion. Periodontal muco-periosteal flap surgery with gingival fiber retention technique was done in the experimental site with internal bevel incision, and in control site, muco periosteal flap surgery with crevicular incision was done. Thereafter, observation period was of one week, four weeks, and eight weeks were done for both the sites. Statistical Analysis Used: The results were subjected to statistical analysis using studentâ€Čs t`-test. Results: The result of this study suggests that the periodontal flap surgery with gingival fiber retention technique has a beneficial effect on the anterior teeth, as it maintains the esthetics, recontours the gingiva with minimal recession. The area of recession was more on the control site as compared to experimental site at 4 weeks, 8 weeks and 12 weeks. Conclusions: Gingival fiber retention technique showed less post-surgical recession and also there was fall in values of plaque index, gingival index, and periodontal index scores, throughout the study.

  7. Healthcare Learning Community and Student Retention

    Science.gov (United States)

    Johnson, Sherryl W.

    2014-01-01

    Teaching, learning, and retention processes have evolved historically to include multifaceted techniques beyond the traditional lecture. This article presents related results of a study using a healthcare learning community in a southwest Georgia university. The value of novel techniques and tools in promoting student learning and retention


  8. Factors affecting nurse retention at an academic MagnetÂź hospital.

    Science.gov (United States)

    Buffington, Annsley; Zwink, Jennifer; Fink, Regina; Devine, Deborah; Sanders, Carolyn

    2012-05-01

    : The aim of this study was to examine the factors affecting the retention of registered nurses (RNs) and validate the revised Casey-Fink Nurse Retention Survey (2009). : Creating an organizational culture of retention may reduce nurse turnover. Focusing on why nurses leave and identifying factors why nurses stay are essential. : A descriptive survey design gathered data from RNs with 1 or more years of experience providing direct patient care and employed in inpatient/ambulatory settings in an acute care, academic, Magnet hospital. : There were no statistically significant relationships between nurse respondents' perceptions of work environment/support/encouragement and age or years of experience. However, there were significant differences between inpatient and ambulatory nurse responses in several key areas including job satisfaction, mentorship, and educational support. Overall, nurses reported feeling a lack of support and recognition from managers. Results provide evidence to support improved strategies to foster nurse retention.

  9. Irradiation Effects Test Series: Test IE-3. Test results report

    International Nuclear Information System (INIS)

    Farrar, L.C.; Allison, C.M.; Croucher, D.W.; Ploger, S.A.

    1977-10-01

    The objectives of the test reported were to: (a) determine the behavior of irradiated fuel rods subjected to a rapid power increase during which the possibility of a pellet-cladding mechanical interaction failure is enhanced and (b) determine the behavior of these fuel rods during film boiling following this rapid power increase. Test IE-3 used four 0.97-m long pressurized water reactor type fuel rods fabricated from previously irradiated fuel. The fuel rods were subjected to a preconditioning period, followed by a power ramp to 69 kW/m at a coolant mass flux of 4920 kg/s-m 2 . After a flow reduction to 2120 kg/s-m 2 , film boiling occurred on the fuel rods. One rod failed approximately 45 seconds after the reactor was shut down as a result of cladding embrittlement due to extensive cladding oxidation. Data are presented on the behavior of these irradiated fuel rods during steady-state operation, the power ramp, and film boiling operation. The effects of a power ramp and power ramp rates on pellet-cladding interaction are discussed. Test data are compared with FRAP-T3 computer model calculations and data from a previous Irradiation Effects test in which four irradiated fuel rods of a similar design were tested. Test IE-3 results indicate that the irradiated state of the fuel rods did not significantly affect fuel rod behavior during normal, abnormal (power ramp of 20 kW/m per minute), and accident (film boiling) conditions

  10. EVALUATION OF WATER RETENTION CAPABILITY IN WETLANDS AT SMALL FOREST CATCHMENT

    Directory of Open Access Journals (Sweden)

    Daniel Liberacki

    2015-07-01

    Full Text Available The paper presents the results of researches carried out in the middle part of Pizza Zielonka forest complex. The aim was the evaluation of retention changes at wetlands and mid-forest ponds. The object of the study was the catchment of the Trojanka watercourse, considering from the origin to the cross-section of Zielonka Lake. The catchment is located in in the central part of the Wielkopolska region, approximatelly 20 km on the North-East of PoznaƄ. The area of this forestall catchment is about 223 ha. In the paper an analysis of the results from three hydrological years was presented. The results of the years 1987 (wet year, 2003 (dry year and 2009 (medium year were analysed against meteorological conditions. Retention capacity in each wetlands, as well as the possibility of water retention in the Trojanka watercourse was calculated. The researches confirmed significant meteorological conditions influence the amount of retentioned water. The calculated capacity of retentioned water was 15 852 m3 considering the total area of wetland and swamp (8,58 ha and precipitation sum of 555 mm. 18% increase of water capacity was observed in wet year (1987 In this year the sum of precipitation was 100 mm higher than multiyear average sum. Meanwhile 62% decrease of water capacity was observed in dry year (2003, when the precipitation sum was 208 mm lower than multiyear average one.

  11. Bile acid malabsorption in patients with chronic diarrhoea: clinical value of SeHCAT test

    DEFF Research Database (Denmark)

    Wildt, Signe; NÞrby Rasmussen, S; Madsen, Jan LysgÄrd

    2003-01-01

    be evaluated. RESULTS: In 44% of patients, bile acid absorption was normal with SeHCAT retention > or = 15%. Impaired SeHCAT retention was found in 56%. All patients with ileocaecal resections had retention values presented with BAM in 39%. Only one patient...... with idiopathic BAM presented with steatorrhoea as opposed to 11 patients with type 1 and 3 BAM. Patients with idiopathic BAM and/or SeHCAT retention values value in evaluation of patients with chronic diarrhoea...... as a second-line investigation with a high diagnostic yield. The only a priori parameter to predict BAM was the existence of ileocaecal resections. The result of the SeHCAT test seems to predict the benefit of treatment with cholestyramine....

  12. 28 CFR 345.67 - Retention of benefits.

    Science.gov (United States)

    2010-07-01

    ... INDUSTRIES (FPI) INMATE WORK PROGRAMS Inmate Pay and Benefits § 345.67 Retention of benefits. (a) Job retention. Ordinarily, when an inmate is absent from the job for a significant period of time, the SOI will... 28 Judicial Administration 2 2010-07-01 2010-07-01 false Retention of benefits. 345.67 Section 345...

  13. Exposure to retrieval cues improves retention performance and induces changes in ACTH and corticosterone release.

    Science.gov (United States)

    Gisquet-Verrier, Pascale; Botreau, Fanny; Venero, Cesar; Sandi, Carmen

    2004-05-01

    Memory retrieval can be facilitated by pretest exposure to cues associated with the original training. The present series of experiments was aimed at investigating whether the effectiveness of the retrieval cues might be due to their emotional value and thus be associated to a particular pattern of activation of stress systems. Therefore, the effects of exposing rats to different cueing conditions were investigated both on retention performance and on the level of different stress hormones (ACTH, corticosterone and glucose; the latter as an indirect index of adrenergic/sympathetic nervous system activation). Rats trained in a brightness avoidance discrimination task exhibited an enhancement of the retention performance following exposure to the light discriminative stimulus when delivered 1-day after training and not after 21 days, while exposure to contextual cues led to opposite effects on the retention performance, confirming our previous results. Analyses of the level of stress hormones at the time of testing indicated that when the retrieval cues were effective at the behavioral level, cued rats exhibited higher ACTH plasmatic levels than controls, but did not differ in their glucose or corticosterone levels. Further experiments showed that one day after training, both ACTH and corticosterone levels were elevated in light-cued rats if hormone samples were taken 15 min after cueing. These results show that exposure to an effective retrieval cue is accompanied by the activation of the hypothalamus-pituitary-adrenal axis. The possible involvement of the Corticotropin Releasing Factor at the level of the hypothalamus and amygdala (particularly the central nucleus) on the facilitating effect on retention performance following exposure to aversive training-associated cues is discussed. The present results strengthen the notion that emotion can interact with retrieval processes.

  14. Retention Among North American HIV–infected Persons in Clinical Care, 2000–2008

    Science.gov (United States)

    Rebeiro, Peter; Althoff, Keri N.; Buchacz, Kate; Gill, M. John; Horberg, Michael; Krentz, Hartmut; Moore, Richard; Sterling, Timothy R.; Brooks, John T.; Gebo, Kelly A.; Hogg, Robert; Klein, Marina; Martin, Jeffrey; Mugavero, Michael; Rourke, Sean; Silverberg, Michael J.; Thorne, Jennifer; Gange, Stephen J.

    2013-01-01

    Background Retention in care is key to improving HIV outcomes. Our goal was to describe “churn” in patterns of entry, exit, and retention in HIV care in the US and Canada. Methods Adults contributing ≄1 CD4 count or HIV-1 RNA (HIV-lab) from 2000–2008 in North American Cohort Collaboration on Research and Design (NA-ACCORD) clinical cohorts were included. Incomplete retention was defined as lack of 2 HIV-labs (≄90 days apart) within 12 months, summarized by calendar year. We used beta-binomial regression models to estimate adjusted odds ratios (OR) and 95% confidence intervals (CI) of factors associated with incomplete retention. Results Among 61,438 participants, 15,360 (25%) with incomplete retention significantly differed in univariate analyses (pchurn. In addition to the programmatic and policy implications, our findings identify patient groups who may benefit from focused retention efforts. PMID:23242158

  15. The impact of presentation style on the retention of online health information: a randomized-controlled experiment.

    Science.gov (United States)

    Frisch, Anne-Linda; Camerini, Luca; Schulz, Peter J

    2013-01-01

    The Internet plays an increasingly important role in health education, providing laypeople with information about health-related topics that range from disease-specific contexts to general health promotion. Compared to traditional health education, the Internet allows the use of multimedia applications that offer promise to enhance individuals' health knowledge and literacy. This study aims at testing the effect of multimedia presentation of health information on learning. Relying on an experimental design, it investigates how retention of information differs for text-only presentation, image-only presentation, and multimedia (text and image) presentation of online health information. Two hundred and forty students were randomly assigned to four groups each exposed to a different website version. Three groups were exposed to the same information using text only, image only, or text and image presentation. A fourth group received unrelated information (control group). Retention was assessed by the means of a recognition test. To examine a possible interaction between website version and recognition test, half of the students received a recognition test in text form and half of them received a recognition test in imagery form. In line with assumptions from Dual Coding Theory, students exposed to the multimedia (text and image) presentation recognized significantly more information than students exposed to the text-only presentation. This did not hold for students exposed to the image-only presentation. The impact of presentation style on retention scores was moderated by the way retention was assessed for image-only presentation, but not for text-only or multimedia presentation. Possible explanations and implications for the design of online health education interventions are discussed.

  16. [Mucoceles of the minor salivary glands. Extravasation mucoceles (mucus granulomas) and retention mucoceles (mucus retention cysts) (author's transl)].

    Science.gov (United States)

    Seifert, G; Donath, K; von Gumberz, C

    1981-06-01

    360 cases of salivary glands cysts (= 6%) were collected in the Salivary Glands Register (Institute of Pathology, University of Hamburg) from 1965 until 1979 among a total of 5739 register cases. 273 cases of the cystic lesions (= 76%) were mucoceles of the minor salivary glands. The analysis of these 273 cases revealed the following results: 1. Two types of mucoceles can be morphologically distinguished: extravasation mucoceles and retention mucoceles. 2. The extravasation mucocele is in our material (240 cases = 88.7%) the most frequent type of mucocele. The term "extravasation mucocele" of the anglo-american literature is identical with the term "mucus granuloma" ("Schleimgranulom") introduced by Hamperl (1932). 3. The main signs of the mucus granulomas are: predominant location (79%) at the lower lip, age peak in the 2nd decade and more frequent occurrence (in 60%) in the male sex. 4. Three stages of development can be distinguished in the pathogenesis of the mucus granulomas: an initial stage (interstitial mucus lakes), a resorption stage (mucus granulomas with macrophages, foam cells and foreign bodies giant cells) and a terminal stage with the development of a pseudocyst (capsule of collagen tissue, no epithelial demarcation). 5. The retention mucocele (synonym: mucus retention cyst) is a rare type of mucocele (33 cases = 11.3%). The main signs are: nearly equal occurrence in all oral regions, age peak in the 8th decade, moderate predominance of the female sex. 6. The retention mucoceles contain viscous mucous material, possess always an epithelial demarcation of the cysts differentiated analogous to the different segments of the salivary duct system and show as a rule no inflammatory reaction compared with the extravasation mucoceles. 7. Microtraumas and mucus congestions play the important role in the development of the extravasation mucocele. The final formation depends on the amount of the overflowed mucus and the intensity of the mucus phagocytosis. 8

  17. Alternative filtration testing program: Pre-evaluation of test results

    International Nuclear Information System (INIS)

    Georgeton, G.K.; Poirier, M.R.

    1990-01-01

    Based on results of testing eight solids removal technologies and one pretreatment option, it is recommended that a centrifugal ultrafilter and polymeric ultrafilter undergo further testing as possible alternatives to the Norton Ceramic filters. Deep bed filtration should be considered as a third alternative, if a backwashable cartridge filter is shown to be inefficient in separate testing

  18. Alternative filtration testing program: Pre-evaluation of test results

    Energy Technology Data Exchange (ETDEWEB)

    Georgeton, G.K.; Poirier, M.R.

    1990-09-28

    Based on results of testing eight solids removal technologies and one pretreatment option, it is recommended that a centrifugal ultrafilter and polymeric ultrafilter undergo further testing as possible alternatives to the Norton Ceramic filters. Deep bed filtration should be considered as a third alternative, if a backwashable cartridge filter is shown to be inefficient in separate testing.

  19. Transport and retention of pollutants from different production systems

    Energy Technology Data Exchange (ETDEWEB)

    Mander, Ue. (Dept. of Geography, Univ. of Tartu (Estonia)); Shirmohammadi, A. (Fischell Dept. of Bioengineering, Univ. of Maryland, MD (United States))

    2008-07-01

    Transport and retentions of agricultural pollutants both at farm level and catchment scale are key challenges faced by researchers, environmental managers, and regulatory agencies. Researchers have responded to this challenge by either monitoring or modelling strategies. Models, both empirical and theoretical, have been developed and used at different scales trying to evaluate the dynamics of the pollutants as they move from upland agricultural areas to water bodies. Monitoring studies at different scales (plot, field, catchment) have tried to represent the natural system and provide data-base for calibrating and testing mathematical models. Scientists have also used both modelling and monitoring strategies to evaluate the impact of different management practices such as contour cropping, vegetated buffer strips, riparian zones, and constructed wetlands on reduction of pollutant loads to water bodies. Manuscripts presented in this special issue provide results of both modelling and monitoring at different scales as they relate to transport and retention of nutrients in different landscapes. For example, it covers application of SWAT model in Finland to meet the environmental goals of European Water Framework Directive, and application of the same model in the US to meet the Total Maximum Daily Load mandated by US's 1972 Clean Water Act. Also covered are results on nutrient and sediment reduction due to different management practices including vegetated buffer strips, riparian zones, and constructed wetlands. Overall results of monitoring indicate effectiveness of such practices in attenuating sediment and nutrients, thus reducing their entry into the water bodies. (orig.)

  20. RAINWATER RETENTION ON THE HEAVILY INDUSTRIALIZED AREAS

    Directory of Open Access Journals (Sweden)

    Bartosz KaĆșmierczak

    2016-06-01

    Full Text Available The paper presents the dimensioning of retention reservoirs indicator method regarding to the German DWA-A 117 guideline, recommended for small rainfall catchments (with an area of 200 ha. A comparative calculation of the retention reservoirs overflow useful volume were conducted for 4 variants of catchment development (degree sealing surface varied from 60% to 90%, under the assumed sewage outflow from the tank at the level of the urban basin natural runoff. At given conditions required unit volume of retention reservoirs, from 145.4 m3 to 206.7 m3 for each 1 ha of catchment area were determined. The obtained results confirmed the fact that useful volume of the tanks were decreased, when Blaszczyk’s pattern reliable rainwater streams were used for calculations. Because the DWA-A 117 guideline method should be applied to a small rainfall catchments, it is recommended to verify the hydraulic capacity of dimensioned channels and objects using hydrodynamic simulations at different load of rainfall catchment scenarios, variable in time and space.

  1. International perspectives on retention and persistence

    Directory of Open Access Journals (Sweden)

    Gary Burkholder

    2014-06-01

    Full Text Available Access to higher education globally is increasing dramatically; attainment of tertiary degrees is a high priority, as educational attainment is associated with increased personal incomes as well as growth of the middle class in developing countries. The purpose of this essay is to briefly examine retention and persistence issues from a global perspective, review some retention strategies that have been employed at schools outside the United States, and to identify several key factors that related to retention and persistence globally, including access, infrastructure, financial consideration, and readiness for tertiary education.  There exists an opportunity to utilize knowledge gained in the evolution of the higher education system in the United States to help address the problems associated with retention and persistence.   DOI: 10.18870/hlrc.v4i2.208

  2. Quantitative structure-retention relationships of pesticides in reversed-phase high-performance liquid chromatography based on WHIM and GETAWAY molecular descriptors

    Energy Technology Data Exchange (ETDEWEB)

    D' Archivio, Angelo Antonio [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy)], E-mail: darchivi@univaq.it; Maggi, Maria Anna; Mazzeo, Pietro; Ruggieri, Fabrizio [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy)

    2008-11-03

    The ability of the Weighted Holistic Invariant Molecular (WHIM) and GEometry, Topology, and Atom-Weights AssemblY (GETAWAY) descriptors to represent the effect of molecular structure on the retention of pesticides in reversed-phase high-performance liquid chromatography (RP-HPLC) is investigated. To this end, two retention data sets previously collected in water-acetonitrile mobile phase are re-examined. The first data set (data-set-1) consists of retention data of 26 neutral compounds belonging to widely used pesticide classes, collected within the mobile phase composition range 40-65% (v/v) acetonitrile. The second data set (data-set-2) describes retention of phenoxy acid herbicides and structurally related compounds (benzoic acid and phenylacetic acid derivatives), as a whole covering the pK{sub a} range 2.3-4.3, as a function of mobile phase composition, ranging between 30 and 70% (v/v) acetonitrile, and pH, ranging between 2 and 5. For each data set, the mobile phase attributes are combined with WHIM or GETAWAY descriptors into 'mixed' predictive models in order to attempt retention modelling within the whole mobile phase composition range of analytical interest. Six- or seven-dimensional multilinear models, preliminarily selected using a genetic algorithm, were improved using a multi-layer artificial neural network (ANN) learned by back propagation. ANN performance was tested on three molecules not used in the learning stage and by leave-more-out cross validation. The results reveal that while WHIM descriptors seem not adequate to model retention of solutes of data-set-1, GETAWAY descriptors provide a satisfactory retention model. On the other hand WHIM and GETAWAY descriptors applied to data-set-2 provide a similar performance, even if slightly worse as compared with the above case. Accuracy of retention modelling in these cases is comparable or slightly poorer as compared with the results previously obtained by combining quantum chemical

  3. Quantitative structure-retention relationships of pesticides in reversed-phase high-performance liquid chromatography based on WHIM and GETAWAY molecular descriptors

    International Nuclear Information System (INIS)

    D'Archivio, Angelo Antonio; Maggi, Maria Anna; Mazzeo, Pietro; Ruggieri, Fabrizio

    2008-01-01

    The ability of the Weighted Holistic Invariant Molecular (WHIM) and GEometry, Topology, and Atom-Weights AssemblY (GETAWAY) descriptors to represent the effect of molecular structure on the retention of pesticides in reversed-phase high-performance liquid chromatography (RP-HPLC) is investigated. To this end, two retention data sets previously collected in water-acetonitrile mobile phase are re-examined. The first data set (data-set-1) consists of retention data of 26 neutral compounds belonging to widely used pesticide classes, collected within the mobile phase composition range 40-65% (v/v) acetonitrile. The second data set (data-set-2) describes retention of phenoxy acid herbicides and structurally related compounds (benzoic acid and phenylacetic acid derivatives), as a whole covering the pK a range 2.3-4.3, as a function of mobile phase composition, ranging between 30 and 70% (v/v) acetonitrile, and pH, ranging between 2 and 5. For each data set, the mobile phase attributes are combined with WHIM or GETAWAY descriptors into 'mixed' predictive models in order to attempt retention modelling within the whole mobile phase composition range of analytical interest. Six- or seven-dimensional multilinear models, preliminarily selected using a genetic algorithm, were improved using a multi-layer artificial neural network (ANN) learned by back propagation. ANN performance was tested on three molecules not used in the learning stage and by leave-more-out cross validation. The results reveal that while WHIM descriptors seem not adequate to model retention of solutes of data-set-1, GETAWAY descriptors provide a satisfactory retention model. On the other hand WHIM and GETAWAY descriptors applied to data-set-2 provide a similar performance, even if slightly worse as compared with the above case. Accuracy of retention modelling in these cases is comparable or slightly poorer as compared with the results previously obtained by combining quantum chemical descriptors or usual

  4. Strategies for improving employee retention.

    Science.gov (United States)

    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.

  5. Retenção de metais pesados em micélio de fungos micorrízicos arbusculares Retention of heavy metals by arbuscular mycorrhizal fungi mycelium

    Directory of Open Access Journals (Sweden)

    Lucélia Cabral

    2010-01-01

    Full Text Available This work evaluated the kinetics as well as the retention capacity of Cu, Zn, Cd, and Pb by arbuscular mycorrhizal fungi (AMF mycelium. The metal retention is a fast process with Cu being retained 3, 30, and 60 times faster than Zn, Cd, and Pb, respectively. Metal retention capacity varied amongst the different tested AMF species and decreased in the following order: Cu>Zn>>Cd>Pb. The Glomus clarum mycelium showed the highest retention capacity for Cu, Cd and Pb, whereas Zn was mostly retained by Gigaspora gigantea mycelium. The simultaneous application of all tested metals in solution decreased Cu and Zn retention by AMF mycelium. The high retention capacity of Cu and Zn by mycelium of G. clarum and G. gigantea suggests a promising use of these isolates in phytoremediation.

  6. Irradiation effects test series test IE-1 test results report

    International Nuclear Information System (INIS)

    Quapp, W.J.; Allison, C.M.; Farrar, L.C.; Mehner, A.S.

    1977-03-01

    The report describes the results of the first programmatic test in the Nuclear Regulatory Commission Irradiation Effects Test Series. This test (IE-1) used four 0.97m long PWR-type fuel rods fabricated from previously irradiated Saxton fuel. The objectives of this test were to evaluate the effect of fuel pellet density on pellet-cladding interaction during a power ramp and to evaluate the influence of the irradiated state of the fuel and cladding on rod behavior during film boiling operation. Data are presented on the behavior of irradiated fuel rods during steady-state operation, a power ramp, and film boiling operation. The effects of as-fabricated gap size, as-fabricated fuel density, rod power, and power ramp rate on pellet-cladding interaction are discussed. Test data are compared with FRAP-T2 computer model predictions, and comments on the consequences of sustained film boiling operation on irradiated fuel rod behavior are provided

  7. phosphorus retention data and metadata

    Science.gov (United States)

    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).

  8. Cigarette smoke retention and bronchodilation in patients with COPD. A controlled randomized trial.

    Science.gov (United States)

    van Dijk, Wouter D; Heijdra, Yvonne; Lenders, Jacques W M; Klerx, Walther; Akkermans, Reinier; van der Pouw, Anouschka; van Weel, Chris; Scheepers, Paul T J; Schermer, Tjard R J

    2013-01-01

    Bronchodilators are the cornerstone for symptomatic treatment of chronic obstructive pulmonary disease (COPD). Many patients use these agents while persisting in their habit of cigarette smoking. We hypothesized that bronchodilators increase pulmonary retention of cigarette smoke and hence the risk of smoking-related (cardiovascular) disease. Our aim was to investigate if bronchodilation causes increased pulmonary retention of cigarette smoke in patients with COPD. A double-blinded, placebo-controlled, randomized crossover trial, in which COPD patients smoked cigarettes during undilated conditions at one session and maximal bronchodilated conditions at the other session. Co-primary outcomes were pulmonary tar and nicotine retention. We performed a secondary analysis that excludes errors due to possible contamination. Secondary outcomes included the biomarkers C-reactive protein and fibrinogen, and smoke inhalation patterns. Of 39 randomized patients, 35 patients completed the experiment and were included in the final analysis. Bronchodilation did not significantly increase tar retention (-4.5%, p = 0.20) or nicotine retention (-2.6%, p = 0.11). Secondary analysis revealed a potential reduction of retention due to bronchodilation: tar retention (-3.8%, p = 0.13), and nicotine retention (-3.4%, p = 0.01). Bronchodilation did not modify our secondary outcomes. Our results do not support the hypothesis that cigarette tar and nicotine retention in COPD patients is increased by bronchodilation, whereas we observed a possibility towards less retention. www.clinicaltrials.gov: NCT00981851. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Immediate and Long-Term Retention For Pictorial and Verbal Stimuli.

    Science.gov (United States)

    Purdy, Jesse E.; Luepnitz, Roy R.

    1982-01-01

    Sixty-four subjects were presented pictures and later asked to draw them or provide one-word descriptions to test the hypothesis that decreased retention effectiveness occurs because images stored in long-term memory are accessible only through their verbal labels. Recall of pictures was significantly greater than recall of words. (Author/PN)

  10. Irradiation effects test series, test IE-5. Test results report. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Croucher, D. W.; Yackle, T. R.; Allison, C. M.; Ploger, S. A.

    1978-01-01

    Test IE-5, conducted in the Power Burst Facility at the Idaho National Engineering Laboratory, employed three 0.97-m long pressurized water reactor type fuel rods, fabricated from previously irradiated zircaloy-4 cladding and one similar rod fabricated from unirradiated cladding. The objectives of the test were to evaluate the influence of simulated fission products, cladding irradiation damage, and fuel rod internal pressure on pellet-cladding interaction during a power ramp and on fuel rod behavior during film boiling operation. The four rods were subjected to a preconditioning period, a power ramp to an average fuel rod peak power of 65 kW/m, and steady state operation for one hour at a coolant mass flux of 4880 kg/s-m/sup 2/ for each rod. After a flow reduction to 1800 kg/s-m/sup 2/, film boiling occurred on one rod. Additional flow reductions to 970 kg/s-m/sup 2/ produced film boiling on the three remaining fuel rods. Maximum time in film boiling was 80s. The rod having the highest initial internal pressure (8.3 MPa) failed 10s after the onset of film boiling. A second rod failed about 90s after reactor shutdown. The report contains a description of the experiment, the test conduct, test results, and results from the preliminary postirradiation examination. Calculations using a transient fuel rod behavior code are compared with the test results.

  11. Potential possibilities of water retention in agricultural loess catchments

    Directory of Open Access Journals (Sweden)

    Zubala Tomasz

    2016-09-01

    Full Text Available The growing water deficit and the increased demand for water, as well as economic problems and inadequate spatial planning in many regions indicate a necessity of developing more effective rules of programming and realisation of works concerning the water management in small catchments. The paper presents a sample analysis of the possibilities of increasing water retention in the agricultural loess catchments with periodic streams. The scope of the study included the determination of physical parameters of selected sub-catchments (geometry, soil cover, land use, etc. and of the sources of threat to water resources, resulting from construction and geomorphological conditions. Pre-design assumptions of dammings were developed, taking into account anti-erosion protective measures, and treatments increasing the landscape retention of water were proposed. Creating surface retention objects should be an important source of water in simplified agroecosystems, especially in regions, where productivity to a great extent depends on natural weather conditions. Proper management of the fourth-order loess basin of the Ciemięga River (area of about 150 km2, the presence of 50 lateral valleys could give a temporary reservoir retention reaching 500 thousand m3. Farmers should be encouraged to seek “own water sources” (including the accumulation of water within wasteland, using appropriate economic instruments (tax reliefs for the documented volume of retained water, e.g. in small retention reservoirs.

  12. Radiological bile acid absorption test {sup 75}SeHCAT in patients with diarrhoea of unknown cause

    Energy Technology Data Exchange (ETDEWEB)

    Rudberg, U. [St. Goeran`s Hospital, Stockholm (Sweden). Dept. of Diagnostic Radiology; Nylander, B. [St. Goeran`s Hospital, Stockholm (Sweden). Dept. of Internal Medicine

    1996-09-01

    Purpose: The purpose with this study was to investigate the usefulness of the {sup 75}SeHCAT test in patients suffering from `functional` diarrhoea and to disclose earlier radiological investigations performed in the course of disease. Material and Methods: Twenty patients with chronic diarrhoea of unknown cause were investigated with the {sup 75}SeHCAT test. The cholestyramine test and an estimation of oro-caecal transit time (OCTT) were also performed in 13 and 10 patients respectively. Results: Ten patients had low 7-day retention ({<=}15%). Nine of these were tested with cholestyramine and 8 showed complete relief from the diarrhoea. The cholestyramine test had no effect on the 4 patients with normal bile acid retention. No correlation was found between the retention of {sup 75}SeHCAT and OCCT. A total of 80 inconclusive gastrointestinal barium examinations were performed during the course of disease. Conclusion: Pathological bile acid retention, studied with the radiological {sup 75}SeHCAT test, is common in patients with diarrhoea of unknown cause. The test should be performed earlier in the course of disease in order to prevent unnecessary radiological investigations and to reduce patient suffering and distress. (orig.).

  13. Employee retention: a customer service approach.

    Science.gov (United States)

    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

  14. Deuterium retention in molten salt electrodeposition tungsten coatings

    International Nuclear Information System (INIS)

    Zhou, Hai-Shan; Xu, Yu-Ping; Sun, Ning-Bo; Zhang, Ying-Chun; Oya, Yasuhisa; Zhao, Ming-Zhong; Mao, Hong-Min; Ding, Fang; Liu, Feng; Luo, Guang-Nan

    2016-01-01

    Highlights: ‱ We investigate D retention in electrodeposition W coatings. ‱ W coatings are exposed to D plasmas in the EAST tokamak. ‱ A cathodic current density dependence on D retention is found. ‱ Electrodeposition W exhibits lower D retention than VPS-W. - Abstract: Molten salt electrodeposition is a promising technology to manufacture the first wall of a fusion reactor. Deuterium (D) retention behavior in molten salt electrodeposition tungsten (W) coatings has been investigated by D-plasma exposure in the EAST tokamak and D-ion implantation in an ion beam facility. Tokamak exposure experiments demonstrate that coatings prepared with lower current density exhibit less D retention and milder surface damage. Deuterium-ion implantation experiments indicate the D retention in the molten salt electrodeposition W is less than that in vacuum plasma spraying W and polycrystalline W.

  15. Deuterium retention in molten salt electrodeposition tungsten coatings

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hai-Shan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Xu, Yu-Ping [Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Sun, Ning-Bo; Zhang, Ying-Chun [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing (China); Oya, Yasuhisa [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka (Japan); Zhao, Ming-Zhong [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Mao, Hong-Min [Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Ding, Fang; Liu, Feng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Luo, Guang-Nan, E-mail: gnluo@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Hefei Center for Physical Science and Technology, Hefei (China); Hefei Science Center of Chinese Academy of Science, Hefei (China)

    2016-12-15

    Highlights: ‱ We investigate D retention in electrodeposition W coatings. ‱ W coatings are exposed to D plasmas in the EAST tokamak. ‱ A cathodic current density dependence on D retention is found. ‱ Electrodeposition W exhibits lower D retention than VPS-W. - Abstract: Molten salt electrodeposition is a promising technology to manufacture the first wall of a fusion reactor. Deuterium (D) retention behavior in molten salt electrodeposition tungsten (W) coatings has been investigated by D-plasma exposure in the EAST tokamak and D-ion implantation in an ion beam facility. Tokamak exposure experiments demonstrate that coatings prepared with lower current density exhibit less D retention and milder surface damage. Deuterium-ion implantation experiments indicate the D retention in the molten salt electrodeposition W is less than that in vacuum plasma spraying W and polycrystalline W.

  16. Application of the Denitrification-Decomposition Model to Predict Carbon Dioxide Emissions under Alternative Straw Retention Methods

    Directory of Open Access Journals (Sweden)

    Can Chen

    2013-01-01

    Full Text Available Straw retention has been shown to reduce carbon dioxide (CO2 emission from agricultural soils. But it remains a big challenge for models to effectively predict CO2 emission fluxes under different straw retention methods. We used maize season data in the Griffith region, Australia, to test whether the denitrification-decomposition (DNDC model could simulate annual CO2 emission. We also identified driving factors of CO2 emission by correlation analysis and path analysis. We show that the DNDC model was able to simulate CO2 emission under alternative straw retention scenarios. The correlation coefficients between simulated and observed daily values for treatments of straw burn and straw incorporation were 0.74 and 0.82, respectively, in the straw retention period and 0.72 and 0.83, respectively, in the crop growth period. The results also show that simulated values of annual CO2 emission for straw burn and straw incorporation were 3.45 t C ha−1 y−1 and 2.13 t C ha−1 y−1, respectively. In addition the DNDC model was found to be more suitable in simulating CO2 mission fluxes under straw incorporation. Finally the standard multiple regression describing the relationship between CO2 emissions and factors found that soil mean temperature (SMT, daily mean temperature (Tmean, and water-filled pore space (WFPS were significant.

  17. Xenon-133 retention in hepatic steatosis - correlation with liver biopsy in 45 patients: concise communication

    International Nuclear Information System (INIS)

    Ahmad, M.; Perrillo, R.P.; Sunwoo, Y.C.; Donati, R.M.

    1979-01-01

    This study presents the results of comparison of hepatic fat content with hepatic xenon retention in 45 patients. The degree of hepatic Xe-133 retention was measured during pulmonary ventilation studies. The amount of hepatic steatosis was graded 0 to 4+ on histologic liver sections obtained by needle or surgical biopsy. There was agreement between the amount of hepatic xenon retention determined scintigraphically and the degree of steatosis determined histologically. These results suggest that Xe-133 retention in the liver provides a simple means of evaluating fatty infiltration of the liver. The potential of this technique as a noninvasive means of investigating hepatic fatty infiltration is discussed

  18. Test results of HTTR control system

    International Nuclear Information System (INIS)

    Motegi, Toshihiro; Iigaki, Kazuhiko; Saito, Kenji; Sawahata, Hiroaki; Hirato, Yoji; Kondo, Makoto; Shibutani, Hideki; Ogawa, Satoru; Shinozaki, Masayuki; Mizushima, Toshihiko; Kawasaki, Kozo

    2006-06-01

    The plant control performance of the IHX helium flow rate control system, the PPWC helium flow rate control system, the secondary helium flow rate control system, the inlet temperature control system, the reactor power control system and the outlet temperature control system of the HTTR are obtained through function tests and power-up tests. As the test results, the control systems show stable control response under transient condition. Both of inlet temperature control system and reactor power control system shows stable operation from 30% to 100%, respectively. This report describes the outline of control systems and test results. (author)

  19. A Cost Benefit Analysis Between the Current Naval Officer Retention Bonus Plan and the Enlisted Retention Bonus Plan

    Science.gov (United States)

    2016-06-01

    that personnel targeted for retention had a direct ability to affect the success of the transaction and company. High potential, job function, job level...and job title rounded out the top five reasons personnel were targeted for retention . In brief, this study found that slightly more than half of...lower income may value the job security provided by service in the military, thus making retention in the military a more attractive option. 4

  20. Impact of Training Deep Vocabulary Learning Strategies on Vocabulary Retention of Iranian EFL Learners

    Directory of Open Access Journals (Sweden)

    Seyed Javad Es-hagi Sardroud

    2013-05-01

    Full Text Available Considering the overall tendency of foreign language learners to use mechanical strategies of rote rehearsal in vocabulary learning and their resistance towards use of 'deep' vocabulary learning strategies, namely contextual guessing, Keyword Method, metacognitive strategy, and semantic mapping, this study intended (a to explore what impact the instruction of these deep strategies, on vocabulary retention of 32 post-intermediate adult EFL Iranian learners, (b to determine how the variable of gender influences the vocabulary retention of students after receiving training in these strategies. To this end, on the basis of a strategy-based model of instruction–CALLA (Chamot & O'Malley, 1994, the experimental group received training in using 'deep' vocabulary learning strategies while the control group received only the common method of vocabulary teaching. After the treatment, following factorial design, the performance of the participants in the teacher-made vocabulary test as posttest was analyzed statistically.  The results indicated higher vocabulary retention for the experimental group, and it was revealed that female students were more receptive to strategy training. This study provides evidence for confirmation of 'depth of processing' hypothesis and the emerging theory about the impact of gender on effective strategy teaching and use, and it recommends incorporation of teaching these 'deep' strategies of vocabulary learning into EFL classrooms.

  1. Cronobacter sakazakii infection alters serotonin transporter and improved fear memory retention in the rats

    Directory of Open Access Journals (Sweden)

    Bhagavathi Sundaram eSivamaruthi

    2015-09-01

    Full Text Available It is well established that Cronobacter sakazakii infection cause septicemia, necrotizingenterocolitis (NEC and meningitis. In the present study, we tested whether the C. sakazakii infection alter the learning and memory through serotonin transporter (SERT. To investigate the possible effect on SERT, on postnatal day (PND-15, wistar rat pups were administered with single dose of C. sakazakii culture (Infected group: IF; 107 CFU or 100ÎŒL of Luria-Bertani broth (LB; Medium Control: MC or without any treatment (NaĂŻve control: NC. All the individuals were subjected to passive avoidance test on PND-30 to test their fear memory. We show that single dose of C. sakazakii infection improved fear memory retention. Subsequently, we show that C. sakazakii infection induced the activation of Toll-like receptor-3 (TLR-3 and heat-shock proteins-90 (Hsp-90. On the other hand, level of serotonin (5-HT and SERT protein was down-regulated. Furthermore, we show that C. sakazakii infection up-regulate microRNA (miR-16 expression. The observed results highlight that C. sakazakii infections was responsible for improved fear memory retention and may have reduced the level of SERT protein, which is possibly associated with the interaction of up-regulated Hsp-90 with SERT protein or miR-16 with SERT mRNA. Taken together, observed results suggest that C. sakazakkii infection alter the fear memory possibly through SERT. Hence, this model may be effective to test the C. sakazakii infection induced changes in synaptic plasticity through SERT and effect of other pharmacological agents against pathogen induced memory disorder.

  2. The effectivity of bentonites in cesium retention of cemented waste products

    International Nuclear Information System (INIS)

    Tello, Cledola Cassia Oliveira de

    2001-01-01

    The nuclear energy has been used for the human development in different areas, as in the medicine, in the agriculture, in the industry and in the environmental protection, besides the electricity generation. As in other activities, in the use of nuclear energy, residues are also generated. They are considered radioactive wastes when the contaminant content can bring a potential negative impact in the human health and in the environment. In this case they should be properly managed and should not be released without treatment. In general the waste processing consists in a volume reduction followed by solidification and/or conditioning. A number of materials can be considered as immobilisation matrices for the wastes, with the objective of maintain the radioactive material physical and chemically stable. The cement is extensively used because it is easy to obtain, there is large. experience in its use and the processing is done at room temperature. Many materials have been studied to improve the fixation characteristics of the radionuclides in the cemented product. The aim of this study was to search, among Brazilian natural materials, those that could be effective in the contaminant retention without jeopardising the process and other characteristics of the waste product. Four types of bentonite were selected to the process and product evaluation tests. Many mixtures were prepared with simulated waste, cement and bentonite in different proportions. The viscosity, set time, compressive strength and leaching were evaluated. In addition it was verified if the products were monolithic and without free water. Inactive caesium was used as tracer. The leaching resistance is the most important parameter in the product evaluation, because it indicates the retention capacity of the matrix for radionuclides when the product is in contact with the water. In 1985 leaching tests were begun and they have been continued till now and from their results it was proved that the

  3. Electrophysiological correlates of the retention of tones differing in timbre in auditory short-term memory.

    Science.gov (United States)

    Nolden, Sophie; Bermudez, Patrick; Alunni-Menichini, Kristelle; Lefebvre, Christine; Grimault, Stephan; Jolicoeur, Pierre

    2013-11-01

    We examined the electrophysiological correlates of retention in auditory short-term memory (ASTM) for sequences of one, two, or three tones differing in timbre but having the same pitch. We focused on event-related potentials (ERPs) during the retention interval and revealed a sustained fronto-central ERP component (most likely a sustained anterior negativity; SAN) that became more negative as memory load increased. Our results are consistent with recent ERP studies on the retention of pitch and suggest that the SAN reflects brain activity mediating the low-level retention of basic acoustic features in ASTM. The present work shows that the retention of timbre shares common features with the retention of pitch, hence supporting the notion that the retention of basic sensory features is an active process that recruits modality-specific brain areas. © 2013 Elsevier Ltd. All rights reserved.

  4. Recruitment and retention of young women into nutrition research studies: practical considerations.

    Science.gov (United States)

    Leonard, Alecia; Hutchesson, Melinda; Patterson, Amanda; Chalmers, Kerry; Collins, Clare

    2014-01-16

    Successful recruitment and retention of participants into research studies is critical for optimising internal and external validity. Research into diet and lifestyle of young women is important due to the physiological transitions experienced at this life stage. This paper aims to evaluate data related to recruitment and retention across three research studies with young women, and present practical advice related to recruiting and retaining young women in order to optimise study quality within nutrition research. Recruitment and retention strategies used in three nutrition studies that targeted young women (18 to 35 years) were critiqued. A randomised controlled trial (RCT), a crossover validation study and a cross-sectional survey were conducted at the University of Newcastle, Australia between 2010 and 2013Successful recruitment was defined as maximum recruitment relative to time. Retention was assessed as maximum participants remaining enrolled at study completion. Recruitment approaches included notice boards, web and social network sites (Facebook and Twitter), with social media most successful in recruitment. The online survey had the highest recruitment in the shortest time-frame (751 participants in one month). Email, phone and text message were used in study one (RCT) and study two (crossover validation) and assisted in low attrition rates, with 93% and 75.7% completing the RCT and crossover validation study respectively. Of those who did not complete the RCT, reported reasons were: being too busy; and having an unrelated illness. Recruiting young women into nutrition research is challenging. Use of social media enhances recruitment, while Email, phone and text message contact improves retention within interventions. Further research comparing strategies to optimise recruitment and retention in young women, including flexible testing times, reminders and incentives is warranted.

  5. Effect of Technetium-99 sources on its retention in low activity waste glass

    Science.gov (United States)

    Luksic, Steven A.; Kim, Dong-Sang; Um, Wooyong; Wang, Guohui; Schweiger, Michael J.; Soderquist, Chuck Z.; Lukens, Wayne; Kruger, Albert A.

    2018-05-01

    Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO2‱2H2O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with heptavalent Tc was used. We postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generally accepted idea. Additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from the glass melt.

  6. Effect of Technetium-99 Sources on Its Retention in Low Activity Waste Glass

    Energy Technology Data Exchange (ETDEWEB)

    Luksic, Steven A.; Kim, Dong-Sang; Um, Wooyong; Wang, Guohui; Schweiger, Michael J.; Soderquist, Chuck Z.; Lukens, Wayne W.; Kruger, Albert A.

    2018-05-01

    Small-scale crucible melting tests on simulated waste glass were performed with technetium-99 (Tc-99) introduced as different species in a representative low activity waste simulant. The glass saw an increase in Tc-99 retention when TcO2∙2H2O and various Tc-minerals containing reduced tetravalent Tc were used compared to tests in which pertechnetate with hexavalent Tc was used. We postulate that the increase of Tc retention is likely caused by different reaction paths for Tc incorporation into glass during early stages of melting, rather than the low volatility of reduced tetravalent Tc compounds, which has been a generally accepted idea. Additional studies are needed to clarify the exact mechanisms relevant to the effect of reduced Tc compounds on Tc incorporation into or volatilization from glass melt.

  7. Variance in exposed perturbations impairs retention of visuomotor adaptation.

    Science.gov (United States)

    Canaveral, Cesar Augusto; Danion, Frédéric; Berrigan, Félix; Bernier, Pierre-Michel

    2017-11-01

    Sensorimotor control requires an accurate estimate of the state of the body. The brain optimizes state estimation by combining sensory signals with predictions of the sensory consequences of motor commands using a forward model. Given that both sensory signals and predictions are uncertain (i.e., noisy), the brain optimally weights the relative reliance on each source of information during adaptation. In support, it is known that uncertainty in the sensory predictions influences the rate and generalization of visuomotor adaptation. We investigated whether uncertainty in the sensory predictions affects the retention of a new visuomotor relationship. This was done by exposing three separate groups to a visuomotor rotation whose mean was common at 15° counterclockwise but whose variance around the mean differed (i.e., SD of 0°, 3.2°, or 4.5°). Retention was assessed by measuring the persistence of the adapted behavior in a no-vision phase. Results revealed that mean reach direction late in adaptation was similar across groups, suggesting it depended mainly on the mean of exposed rotations and was robust to differences in variance. However, retention differed across groups, with higher levels of variance being associated with a more rapid reversion toward nonadapted behavior. A control experiment ruled out the possibility that differences in retention were accounted for by differences in success rates. Exposure to variable rotations may have increased the uncertainty in sensory predictions, making the adapted forward model more labile and susceptible to change or decay. NEW & NOTEWORTHY The brain predicts the sensory consequences of motor commands through a forward model. These predictions are subject to uncertainty. We use visuomotor adaptation and modulate uncertainty in the sensory predictions by manipulating the variance in exposed rotations. Results reveal that variance does not influence the final extent of adaptation but selectively impairs the retention of

  8. Nitrogen Saturation in Highly Retentive Watersheds?

    Science.gov (United States)

    Daley, M. L.; McDowell, W. H.

    2009-12-01

    Watershed managers are often concerned with minimizing the amount of N delivered to N-limited estuaries and coastal zones. A major concern is that watersheds might reach N saturation, in which N delivered to coastal zones increases due to declines in the efficiency of N retention despite constant or even reduced N inputs. We have quantified long-term changes in N inputs (atmospheric deposition, imported food and agricultural fertilizers), outputs (N concentration and export) and retention in the urbanizing Lamprey River watershed in coastal NH. Overall, the Lamprey watershed is 70% forested, receives about 13.5 kg N/ha/yr and has a high rate of annual N retention (85%). Atmospheric deposition (8.7 kg/ha/yr) is the largest N input to the watershed. Of the 2.2 kg N/ha/yr exported in the Lamprey River, dissolved organic N (DON) is the dominant form (50% of total) and it varies spatially throughout the watershed with wetland cover. Nitrate accounts for 30% of the N exported, shows a statistically significant increase from 1999 to 2009, and its spatial variability in both concentration and export is related to human population density. In sub-basins throughout the Lamprey, inorganic N retention is high (85-99%), but the efficiency of N retention declines sharply with increased human population density and associated anthropogenic N inputs. N assimilation in the vegetation, denitrification to the atmosphere and storage in the groundwater pool could all be important contributors to the current high rates of N retention. The temporal and spatial patterns that we have observed in nitrate concentration and export are driven by increases in N inputs and impervious surfaces over time, but the declining efficiency of N retention suggests that the watershed may also be reaching N saturation. The downstream receiving estuary, Great Bay, already suffers from low dissolved oxygen levels and eelgrass loss in part due to N loading from the Lamprey watershed. Targeting and reducing

  9. Retention in HIV care depends on patients' perceptions of the clinic experience.

    Science.gov (United States)

    Wessinger, Matthew H; Hennink, Monique M; Kaiser, Bonnie N; Mangal, Jed P; Gokhale, Runa H; Ruchin, Lauren; Moanna, Abeer; Rimland, David; Farber, Eugene W; Marconi, Vincent C

    2017-10-01

    Institutional barriers in HIV primary care settings can contribute substantially to disparities in retention in HIV treatment and HIV-related outcomes. This qualitative study compared the perceptions of clinic experiences of persons living with HIV (PLWH) in a Veterans Affairs HIV primary care clinic setting who were retained in care with the experiences of those who were not retained in care. Qualitative data from 25 in-depth interviews were analyzed to identify facilitators and barriers to retention in HIV care. Results showed that participants not retained in care experienced barriers to retention involving dissatisfaction with clinic wait times, low confidence in clinicians, and customer service concerns. For participants retained in care, patience with procedural issues, confidence in clinicians, and interpersonal connections were factors that enhanced retention despite the fact that these participants recognized the same barriers as those who were not retained in care. These findings can inform interventions aimed at improving retention in HIV care.

  10. Influence of post pattern and resin cement curing mode on the retention of glass fibre posts.

    Science.gov (United States)

    Poskus, L T; Sgura, R; ParagĂł, F E M; Silva, E M; GuimarĂŁes, J G A

    2010-04-01

    To evaluate the influence of post design and roughness and cement system (dual- or self-cured) on the retention of glass fibre posts. Two tapered and smooth posts (Exacto CĂŽnico No. 2 and White Post No. 1) and two parallel-sided and serrated posts (Fibrekor 1.25 mm and Reforpost No. 2) were adhesively luted with two different resin cements--a dual-cured (Rely-X ARC) and a self-cured (Cement Post)--in 40 single-rooted teeth. The teeth were divided into eight experimental groups (n = 5): PFD--Parallel-serrated-Fibrekor/dual-cured; PRD--Parallel-serrated-Reforpost/dual-cured; TED--Tapered-smooth-Exacto CĂŽnico/dual-cured; TWD--Tapered-smooth-White Post/dual-cured; PFS--Parallel-serrated-Fibrekor/self-cured; PRS--Parallel-serrated-Reforpost/self-cured; TES--Tapered-smooth-Exacto CĂŽnico/self-cured; TWS--Tapered-smooth-White Post/self-cured. The specimens were submitted to a pull-out test at a crosshead speed of 0.5 mm min(-1). Data were analysed using analysis of variance and Bonferroni's multiple comparison test (alpha = 0.05). Pull-out results (MPa) were: PFD = 8.13 (+/-1.71); PRD = 8.30 (+/-0.46); TED = 8.68 (+/-1.71); TWD = 9.35 (+/-1.99); PFS = 8.54 (+/-2.23); PRS = 7.09 (+/-1.96); TES = 8.27 (+/-3.92); TWS = 7.57 (+/-2.35). No statistical significant difference was detected for posts and cement factors and their interaction. The retention of glass fibre posts was not affected by post design or surface roughness nor by resin cement-curing mode. These results imply that the choice for serrated posts and self-cured cements is not related to an improvement in retention.

  11. Green roof stormwater retention: effects of roof surface, slope, and media depth.

    Science.gov (United States)

    VanWoert, Nicholaus D; Rowe, D Bradley; Andresen, Jeffrey A; Rugh, Clayton L; Fernandez, R Thomas; Xiao, Lan

    2005-01-01

    Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event.

  12. Engineering model cryocooler test results

    International Nuclear Information System (INIS)

    Skimko, M.A.; Stacy, W.D.; McCormick, J.A.

    1992-01-01

    This paper reports that recent testing of diaphragm-defined, Stirling-cycle machines and components has demonstrated cooling performance potential, validated the design code, and confirmed several critical operating characteristics. A breadboard cryocooler was rebuilt and tested from cryogenic to near-ambient cold end temperatures. There was a significant increase in capacity at cryogenic temperatures and the performance results compared will with code predictions at all temperatures. Further testing on a breadboard diaphragm compressor validated the calculated requirement for a minimum axial clearance between diaphragms and mating heads

  13. Irradiation Effects Test Series: Test IE-2. Test results report

    International Nuclear Information System (INIS)

    Allison, C.M.; Croucher, D.W.; Ploger, S.A.; Mehner, A.S.

    1977-08-01

    The report describes the results of a test using four 0.97-m long PWR-type fuel rods with differences in diametral gap and cladding irradiation. The objective of this test was to provide information about the effects of these differences on fuel rod behavior during quasi-equilibrium and film boiling operation. The fuel rods were subjected to a series of preconditioning power cycles of less than 30 kW/m. Rod powers were then increased to 68 kW/m at a coolant mass flux of 4900 kg/s-m 2 . After one hour at 68 kW/m, a power-cooling-mismatch sequence was initiated by a flow reduction at constant power. At a flow of 2550 kg/s-m 2 , the onset of film boiling occurred on one rod, Rod IE-011. An additional flow reduction to 2245 kg/s-m 2 caused the onset of film boiling on the remaining three rods. Data are presented on the behavior of fuel rods during quasiequilibrium and during film boiling operation. The effects of initial gap size, cladding irradiation, rod power cycling, a rapid power increase, and sustained film boiling are discussed. These discussions are based on measured test data, preliminary postirradiation examination results, and comparisons of results with FRAP-T3 computer model calculations

  14. Summary of CCTF test results

    International Nuclear Information System (INIS)

    Iguchi, T.; Murao, Y.; Sugimoto, J.; Akimoto, H.; Okubo, T.; Hojo, T.

    1987-01-01

    Conservatism of current safety analysis was assessed by comparing the predicted result with cylindrical core test facility (CCTF) test result performed at Japan Atomic Energy Research Institute. WREM code was selected for the assessment. The overall conservatism of the WREM code on the peak clad temperature prediction was confirmed against CCTF evaluation model (EM) test which simulated the typical initial and boundary conditions in the safety evaluation analysis. WREM code predicted the reasonable core boundary conditions and the conservatism of the code came mainly from core calculation. The conservatism of the WREM code against CCTF data could be attributed to the following three points: (1) no horizontal mixing assumption between subchannels at each elevation; (2) no modeling on heat transfer enhancement caused by the radial core power profile; and (3) conservative heat transfer correlations in the code

  15. The Retentive Strength of Cemented Zirconium Oxide Crowns after Dentin Pretreatment with Desensitizing Paste Containing 8% Arginine and Calcium Carbonate

    Science.gov (United States)

    Pilo, Raphael; Harel, Noga; Nissan, Joseph; Levartovsky, Shifra

    2016-01-01

    The effect of dentin pretreatment with Desensitizing Paste containing 8% arginine and calcium carbonate on the retention of zirconium oxide (Y-TZP) crowns was tested. Forty molar teeth were mounted and prepared using a standardized protocol. Y-TZP crowns were produced using computer-aided design and computer-aided manufacturing (CAD-CAM) technology. The 40 prepared teeth were either pretreated with Desensitizing Paste or not pretreated. After two weeks, each group was subdivided into two groups, cemented with either Resin Modified Glass Ionomer Cement (RMGIC) or Self Adhesive Resin Cement (SARC)). Prior to cementation, the surface areas of the prepared teeth were measured. After aging, the cemented crown-tooth assemblies were tested for retentive strength using a universal testing machine. The debonded surfaces of the teeth and crowns were examined microscopically at 10× magnification. Pretreating the dentin surfaces with Desensitizing Paste prior to cementation did not affect the retention of the Y-TZP crowns. The retentive values for RMGIC (3.04 ± 0.77 MPa) were significantly higher than those for SARC (2.28 ± 0.58 MPa). The predominant failure modes for the RMGIC and SARC were adhesive cement-dentin and adhesive cement-crown, respectively. An 8.0% arginine and calcium carbonate in-office desensitizing paste can be safely used to reduce post-cementation sensitivity without reducing the retentive strength of Y-TZP crowns. PMID:27023532

  16. The Retentive Strength of Cemented Zirconium Oxide Crowns after Dentin Pretreatment with Desensitizing Paste Containing 8% Arginine and Calcium Carbonate

    Directory of Open Access Journals (Sweden)

    Raphael Pilo

    2016-03-01

    Full Text Available The effect of dentin pretreatment with Desensitizing Paste containing 8% arginine and calcium carbonate on the retention of zirconium oxide (Y-TZP crowns was tested. Forty molar teeth were mounted and prepared using a standardized protocol. Y-TZP crowns were produced using computer-aided design and computer-aided manufacturing (CAD-CAM technology. The 40 prepared teeth were either pretreated with Desensitizing Paste or not pretreated. After two weeks, each group was subdivided into two groups, cemented with either Resin Modified Glass Ionomer Cement (RMGIC or Self Adhesive Resin Cement (SARC. Prior to cementation, the surface areas of the prepared teeth were measured. After aging, the cemented crown-tooth assemblies were tested for retentive strength using a universal testing machine. The debonded surfaces of the teeth and crowns were examined microscopically at 10× magnification. Pretreating the dentin surfaces with Desensitizing Paste prior to cementation did not affect the retention of the Y-TZP crowns. The retentive values for RMGIC (3.04 ± 0.77 MPa were significantly higher than those for SARC (2.28 ± 0.58 MPa. The predominant failure modes for the RMGIC and SARC were adhesive cement-dentin and adhesive cement-crown, respectively. An 8.0% arginine and calcium carbonate in-office desensitizing paste can be safely used to reduce post-cementation sensitivity without reducing the retentive strength of Y-TZP crowns.

  17. End-task versus in-task feedback to increase procedural learning retention during spinal anaesthesia training of novices.

    Science.gov (United States)

    Lean, Lyn Li; Hong, Ryan Yee Shiun; Ti, Lian Kah

    2017-08-01

    Communication of feedback during teaching of practical procedures is a fine balance of structure and timing. We investigate if continuous in-task (IT) or end-task feedback (ET) is more effective in teaching spinal anaesthesia to medical students. End-task feedback was hypothesized to improve both short-term and long-term procedural learning retention as experiential learning promotes active learning after encountering errors during practice. Upon exposure to a 5-min instructional video, students randomized to IT or ET feedbacks were trained using a spinal simulator mannequin. A blinded expert tested the students using a spinal anaesthesia checklist in the short term (immediate) and long-term (average 4 months). Sixty-five students completed the training and testing. There were no differences in demographics of age or gender within IT or ET distributions. Both short-term and long-term learning retention of spinal anaesthesia ET feedback proved to be better (P feedback. The time taken for ET students was shorter at long-term testing. End-task feedback improves both short-term and long-term procedural learning retention.

  18. All of the above: When multiple correct response options enhance the testing effect.

    Science.gov (United States)

    Bishara, Anthony J; Lanzo, Lauren A

    2015-01-01

    Previous research has shown that multiple choice tests often improve memory retention. However, the presence of incorrect lures often attenuates this memory benefit. The current research examined the effects of "all of the above" (AOTA) options. When such options are correct, no incorrect lures are present. In the first three experiments, a correct AOTA option on an initial test led to a larger memory benefit than no test and standard multiple choice test conditions. The benefits of a correct AOTA option occurred even without feedback on the initial test; for both 5-minute and 48-hour retention delays; and for both cued recall and multiple choice final test formats. In the final experiment, an AOTA question led to better memory retention than did a control condition that had identical timing and exposure to response options. However, the benefits relative to this control condition were similar regardless of the type of multiple choice test (AOTA or not). Results suggest that retrieval contributes to multiple choice testing effects. However, the extra testing effect from a correct AOTA option, rather than being due to more retrieval, might be due simply to more exposure to correct information.

  19. Cellular retention of radioactivity and increased radiation dose. Model experiments with EGF-dextran

    International Nuclear Information System (INIS)

    Sundberg, Aasa Liljegren; Blomquist, Erik; Carlsson, Joergen; Steffen, Ann-Charlott; Gedda, Lars

    2003-01-01

    Targeting of tumor cells with radiolabeled biomolecules is a possible approach to inactivate disseminated tumor cells. However, rapid degradation of the biomolecules after cellular internalization and subsequent excretion of the radioactivity is a problem. We studied the possibility of using dextran as a carrier of radionuclides to improve the intracellular retention. An EGF-dextran conjugate, aimed for targeting of tumor cells overexpressing the EGF-receptor, was used as model. Retention tests were performed with 125 I on different parts: [ 125 I]-EGF-dextran-[ 125 I], [ 125 I]-EGF-dextran and EGF-dextran-[ 125 I]. Comparisons were made with [ 125 I]-EGF. The radiolabeled compounds were incubated with cultured glioma cells for different times. The cellular retention of radioactivity was then measured for up to 24 h. Expected radiation doses at the cellular level were calculated assuming that 131 I, instead of 125 I, was coupled to EGF and EGF-dextran. The results indicated that the EGF-part of the conjugate was degraded and the EGF-attached radioactivity was rapidly excreted, whereas radioactivity on dextran was retained intracellularly to a high degree, i.e. 70-80% of the radioactivity bound to dextran was still cell-associated after 24 h. The retention after 24 h was significantly higher (p < 0.001) when the radioactivity was on the dextran instead of the EGF-part. The radiolabeled EGF-dextran had a notably high specific radioactivity; up to 11 MBq/ÎŒg. There was potential for at least hundred times increased radiation dose per receptor interaction when the radioactivity was on the dextran part. The advantage with radioactivity on the dextran part was the high cellular retention and the high specific radioactivity (higher than previously reported for other residualizing labels) without severe loss of receptor specific binding. Thus, dextran seems suitable as a carrier of radionuclides aimed for therapy and gives potential for a highly increased radiation dose

  20. A strategic approach to employee retention.

    Science.gov (United States)

    Gering, John; Conner, John

    2002-11-01

    A sound retention strategy should incorporate a business plan, a value proposition, progress measures, and management influences. The business plan will indicate whether a healthcare organization will achieve a return on investment for its effort. A value proposition will showcase an organization's strengths and differentiate it from its competitors. Measuring progress toward meeting retention goals at regular intervals will help keep an organization on track. The best managers require accountability, rewarding employees for their successes and taking corrective action as necessary. Retention rate targets must be at a level that will achieve a competitive advantage in the served market.

  1. Retention of radium from thermal waters on sand filters and adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Elejalde, C. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inpelsac@bi.ehu.es; Herranz, M. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Romero, F. [Dpto. de Ingenieria Quimica y del Medio Ambiente, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Baeza, A. [Dpto. de Fisica, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s/n, 10071 Caceres (Spain)

    2007-06-18

    This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research.

  2. Retention of radium from thermal waters on sand filters and adsorbents

    International Nuclear Information System (INIS)

    Elejalde, C.; Herranz, M.; Idoeta, R.; Legarda, F.; Romero, F.; Baeza, A.

    2007-01-01

    This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research

  3. Retention/Diffusivity Studies in Free-Surface Flowing Liquid Lithium

    International Nuclear Information System (INIS)

    R.A. Stubbers; G.H. Miley; M. Nieto; W. Olczak; D.N. Ruzic; A. Hassanein

    2004-01-01

    FLIRE was designed to measure the hydrogen and helium retention and diffusivity in a flowing stream of liquid lithium, and it has accomplished these goals. Retention coefficients for helium in the flowing liquid stream were 0.1-2% for flow speeds of 44 cm/s and implantation energies between 500 and 2000 eV. The energy dependence of retention is linear for the energy range considered, as expected, and the dependence of retention on flow velocity fits the expected square-root of flow speed dependence. Estimates of the helium diffusion coefficient in the flowing lithium stream were ∌ 4 x 10 -7 cm 2 /s, and are independent of implantation energy. This value is much lower than expected, which could be due to several factors, such as mixing, bubble formation or surface film formation. In the case of hydrogen, long term retention and release mechanisms are of greatest importance, since this relates to tritium inventory in flowing lithium PFCs for fusion applications. The amount of hydride formation was measured for flowing lithium exposed to neutral deuterium gas. Thermal desorption spectroscopy (TDS) measurements indicate that the hydride concentration was between 0.1 and 0.2% over a wide range of pressures (6.5 x 10 -5 to 1 Torr). This result implies that the deuterium absorption rate is limited by the surface dissociation rate, since deuterium (hydrogen/tritium) is absorbed in its atomic form, not its molecular form

  4. Retention/Diffusivity Studies in Free-Surface Flowing Liquid Lithium

    Energy Technology Data Exchange (ETDEWEB)

    R.A. Stubbers; G.H. Miley; M. Nieto; W. Olczak; D.N. Ruzic; A. Hassanein

    2004-12-14

    FLIRE was designed to measure the hydrogen and helium retention and diffusivity in a flowing stream of liquid lithium, and it has accomplished these goals. Retention coefficients for helium in the flowing liquid stream were 0.1-2% for flow speeds of 44 cm/s and implantation energies between 500 and 2000 eV. The energy dependence of retention is linear for the energy range considered, as expected, and the dependence of retention on flow velocity fits the expected square-root of flow speed dependence. Estimates of the helium diffusion coefficient in the flowing lithium stream were {approx} 4 x 10{sup -7} cm{sup 2}/s, and are independent of implantation energy. This value is much lower than expected, which could be due to several factors, such as mixing, bubble formation or surface film formation. In the case of hydrogen, long term retention and release mechanisms are of greatest importance, since this relates to tritium inventory in flowing lithium PFCs for fusion applications. The amount of hydride formation was measured for flowing lithium exposed to neutral deuterium gas. Thermal desorption spectroscopy (TDS) measurements indicate that the hydride concentration was between 0.1 and 0.2% over a wide range of pressures (6.5 x 10{sup -5} to 1 Torr). This result implies that the deuterium absorption rate is limited by the surface dissociation rate, since deuterium (hydrogen/tritium) is absorbed in its atomic form, not its molecular form.

  5. Encopresis in children: a cyclical model of constipation and faecal retention.

    Science.gov (United States)

    Swanwick, T

    1991-01-01

    Encopresis afflicts one in 100 children causing considerable stigma and parental concern. General practitioners are in a position to help in most cases but are often deterred by the psychoanalytical theories which have been developed to explain this problem. It is currently accepted that children with encopresis tend to retain stools. This leads to constipation, overstretching of sphincters and resultant faecal soiling. Physical and psychological perpetuating factors result in retention once again, thus completing a cycle of constipation and retention. Various precipitant and predisposing factors can maintain this cycle. Once physical causes have been excluded a simple behavioural approach can be adopted aimed at retraining the bowel. By using laxatives to prevent retention, gaining the child's confidence, cooperation and understanding and involving both the family and school, encopresis can be successfully managed in general practice. PMID:1807329

  6. Retention factors in relation to organisational commitment in medical and information technology services

    Directory of Open Access Journals (Sweden)

    Jeannette van Dyk

    2012-07-01

    Research purpose: The objectives of the study were to investigate empirically: (1 the relationship between employees’ satisfaction with organisational retention factors (measured by the Retention Factors Scale and their organisational commitment (measured by the Organisational Commitment Questionnaire and (2 whether gender, age, race and tenure groups differ significantly in terms of these variables. Motivation for the study: Medical and information technology professionals have specialised and hard to replace skills. They also have strong tendencies to leave their organisations and countries. Understanding the retention factors that will increase their organisational commitment may benefit the organisations who want to retain their valuable talent. Research design, approach and method: The researchers used a cross-sectional survey design to collect data from a purposive sample of 206 staff members who had scarce skills in a South African medical and information technology services company. Correlational and inferential statistics were computed to achieve the objectives. Main findings: The results showed that the participants’ satisfaction with retention factors has a significant relationship with their organisational commitment and that the biographical groups differ significantly in terms of the variables. Practical/managerial implications: The measured retention factors were all associated with human resource management practices that influence employees’ intentions to leave. Contribution/value-add: The results are important to managers who are interested in retaining staff who have scarce skills and provide valuable pointers for designing effective retention strategies.

  7. Retention and Deformation of Cobalt-Chromium and High-Impact Polyamide Clasps

    Directory of Open Access Journals (Sweden)

    ÖvĂŒl KĂŒmbĂŒloğlu

    2018-04-01

    Full Text Available Objective: The use of metal clasps especially in anterior region may cause aesthetic problems. Polyamide resin has been suggested as an alternative aesthetic denture clasp material. This study compared the retentive force and deformation of cobalt-chromium and polyamide clasps after 36 months of simulated clinical use. Materials and Methods: The retentive force for clasp removal was measured in distilled water using a custom-made apparatus with intervals corresponding to 0, 6, 12, 18, 24, 30 and 36 months of simulated clinical use. The distance (mm between the retentive and reciprocal clasp tips was measured using a microscope before and after the insertion-removal procedures. Results: Significant difference was observed in distance between clasp tips for metal clasps between baseline and 36 months for molars and premolars (p0.05. Conclusion: Polyamide clasps could be alternative to metal clasps particularly on premolars with reliable retention and deformation.

  8. Employee retention and integrated disability management practices as demand side factors.

    Science.gov (United States)

    Habeck, Rochelle; Hunt, Allan; Rachel, Colleen Head; Kregel, John; Chan, Fong

    2010-12-01

    Demand-side employment research on company policies and practices related to retention and absence and disability management (ADM) can contribute to our understanding of employment issues related to people with disabilities from the employers' perspective. To examine company ADM and retention practices and their effectiveness, as well as how these company policies and practices might influence hiring of people with disabilities. Disability Management Employer Coalition employer members (N = 650) were surveyed by internet and the survey data were analyzed using descriptive statistics, correlation, and multiple regression. Ninety-five participants responded to the survey resulting in a response rate of 14%. Retention practice was found to be associated with retention effectiveness (r = .39, P ideas and involvement of employees, and assuring they know how their work and performance support the mission. ADM practice was related to improving health and managing health conditions (r = .26, P companies.

  9. A Low Leakage Autonomous Data Retention Flip-Flop with Power Gating Technique

    Directory of Open Access Journals (Sweden)

    Xiaohui Fan

    2014-01-01

    Full Text Available With the scaling of technology process, leakage power becomes an increasing portion of total power. Power gating technology is an effective method to suppress the leakage power in VLSI design. When the power gating technique is applied in sequential circuits, such as flip-flops and latches, the data retention is necessary to store the circuit states. A low leakage autonomous data retention flip-flop (ADR-FF is proposed in this paper. Two high-Vth transistors are utilized to reduce the leakage power consumption in the sleep mode. The data retention cell is composed of a pair of always powered cross-coupled inverters in the slave latch. No extra control signals and complex operations are needed for controlling the data retention and restoration. The data retention flip-flops are simulated with NCSU 45 nm technology. The postlayout simulation results show that the leakage power of the ADR-FF reduces 51.39% compared with the Mutoh-FF. The active power of the ADR-FF is almost equal to other data retention flip-flops. The average state mode transition time of ADR-FF decreases 55.98%, 51.35%, and 21.07% as compared with Mutoh-FF, Balloon-FF, and Memory-TG-FF, respectively. Furthermore, the area overhead of ADR-FF is smaller than other data retention flip-flops.

  10. Modelling of retention of pesticides in reversed-phase high-performance liquid chromatography: Quantitative structure-retention relationships based on solute quantum-chemical descriptors and experimental (solvatochromic and spin-probe) mobile phase descriptors

    International Nuclear Information System (INIS)

    D'Archivio, Angelo Antonio; Ruggieri, Fabrizio; Mazzeo, Pietro; Tettamanti, Enzo

    2007-01-01

    A quantitative structure-retention relationship (QSRR) analysis based on multilinear regression (MLR) and artificial neural networks (ANNs) is carried out to model the combined effect of solute structure and eluent composition on the retention behaviour of pesticides in isocratic reversed-phase high-performance liquid chromatography (RP-HPLC). The octanol-water partition coefficient and four quantum chemical descriptors (the total dipole moment, the mean polarizability, the anisotropy of the polarizability and a descriptor of hydrogen-bonding based on the atomic charges on acidic and basic chemical functionalities) are considered as solute descriptors. In order to identify suitable mobile phase descriptors, encoding composition-dependent properties of both methanol- and acetonitrile-containing mobile phases, the Kamlet-Taft solvatochromic parameters (polarity-dipolarity, hydrogen-bond acidity and hydrogen-bond basicity, π * , α and ÎČ, respectively) and the 14 N hyperfine-splitting constant (a N ) of a spin-probe dissolved in the eluent are examined. A satisfactory description of mobile phase properties influencing the solute retention is provided by a N and ÎČ or alternatively π * and ÎČ. The two seven-parameter models resulting from combination of a N and ÎČ, or π * and ÎČ, with the solute descriptors were tested on a set of 26 pesticides representative of 10 different chemical classes in a wide range of mobile phase composition (30-60% (v/v) water-methanol and 30-70% (v/v) water-acetonitrile). Within the explored experimental range, the acidity of the eluent, as quantified by α, is almost constant, and this parameter is in fact irrelevant. The results reveal that a N and π * , that can be considered as interchangeable mobile phase descriptors, are the most influent variables in the respective models. The predictive ability of the proposed models, as tested on an external data set, is quite good (Q 2 close to 0.94) when a MLR approach is used, but the

  11. Modelling of retention of pesticides in reversed-phase high-performance liquid chromatography: Quantitative structure-retention relationships based on solute quantum-chemical descriptors and experimental (solvatochromic and spin-probe) mobile phase descriptors

    Energy Technology Data Exchange (ETDEWEB)

    D' Archivio, Angelo Antonio [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy)]. E-mail: darchivi@univaq.it; Ruggieri, Fabrizio [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy); Mazzeo, Pietro [Dipartimento di Chimica, Ingegneria Chimica e Materiali, Universita degli Studi di L' Aquila, Via Vetoio, 67010 Coppito, L' Aquila (Italy); Tettamanti, Enzo [Dipartimento di Scienze Biomediche Comparate, Universita di Teramo, P.zzale A. Moro 45, 64100 Teramo (Italy)

    2007-06-19

    A quantitative structure-retention relationship (QSRR) analysis based on multilinear regression (MLR) and artificial neural networks (ANNs) is carried out to model the combined effect of solute structure and eluent composition on the retention behaviour of pesticides in isocratic reversed-phase high-performance liquid chromatography (RP-HPLC). The octanol-water partition coefficient and four quantum chemical descriptors (the total dipole moment, the mean polarizability, the anisotropy of the polarizability and a descriptor of hydrogen-bonding based on the atomic charges on acidic and basic chemical functionalities) are considered as solute descriptors. In order to identify suitable mobile phase descriptors, encoding composition-dependent properties of both methanol- and acetonitrile-containing mobile phases, the Kamlet-Taft solvatochromic parameters (polarity-dipolarity, hydrogen-bond acidity and hydrogen-bond basicity, {pi} {sup *}, {alpha} and {beta}, respectively) and the {sup 14}N hyperfine-splitting constant (a {sub N}) of a spin-probe dissolved in the eluent are examined. A satisfactory description of mobile phase properties influencing the solute retention is provided by a {sub N} and {beta} or alternatively {pi} {sup *} and {beta}. The two seven-parameter models resulting from combination of a {sub N} and {beta}, or {pi} {sup *} and {beta}, with the solute descriptors were tested on a set of 26 pesticides representative of 10 different chemical classes in a wide range of mobile phase composition (30-60% (v/v) water-methanol and 30-70% (v/v) water-acetonitrile). Within the explored experimental range, the acidity of the eluent, as quantified by {alpha}, is almost constant, and this parameter is in fact irrelevant. The results reveal that a {sub N} and {pi} {sup *}, that can be considered as interchangeable mobile phase descriptors, are the most influent variables in the respective models. The predictive ability of the proposed models, as tested on an

  12. The Retention of Female Unrestricted Line Officers

    National Research Council Canada - National Science Library

    Pecenco, Elena G

    2005-01-01

    This thesis analyzes the retention of female Naval officers, focusing on the relationship between officer selection metrics and retention beyond minimum service obligation and the effect of lateral...

  13. Reduced activity of 11beta-hydroxysteroid dehydrogenase type 2 is not responsible for sodium retention in nephrotic rats

    DEFF Research Database (Denmark)

    Bistrup, C; Thiesson, H C; Jensen, B L

    2005-01-01

    AIM: In mineralocorticoid target cells 11-beta-hydroxysteroid dehydrogenase type 2 (11betaHSD2) converts glucocorticoids into non-active metabolites thereby protecting the mineralocorticoid receptor (MR) from stimulation by glucocorticoids. In nephrotic syndrome, a decreased activity of 11betaHSD2...... has been suggested to allow glucocorticoids to stimulate MR, thereby contributing to sodium retention. We tested this hypothesis in the puromycin aminonucleoside model of nephrotic syndrome in rats. METHODS: Complete sodium and potassium intakes and excretions (faeces and urine) were measured in rats......)] to suppress endogenous glucocorticoids in the proteinuric stage during active sodium retention. RESULTS: Nephrotic rats developed proteinuria, positive sodium balance, decreased plasma aldosterone concentration, and decreased urinary Na(+)/K(+) ratio. 11betaHSD2 mRNA expression was down-regulated but protein...

  14. The confidence-accuracy relationship for eyewitness identification decisions: Effects of exposure duration, retention interval, and divided attention.

    Science.gov (United States)

    Palmer, Matthew A; Brewer, Neil; Weber, Nathan; Nagesh, Ambika

    2013-03-01

    Prior research points to a meaningful confidence-accuracy (CA) relationship for positive identification decisions. However, there are theoretical grounds for expecting that different aspects of the CA relationship (calibration, resolution, and over/underconfidence) might be undermined in some circumstances. This research investigated whether the CA relationship for eyewitness identification decisions is affected by three, forensically relevant variables: exposure duration, retention interval, and divided attention at encoding. In Study 1 (N = 986), a field experiment, we examined the effects of exposure duration (5 s vs. 90 s) and retention interval (immediate testing vs. a 1-week delay) on the CA relationship. In Study 2 (N = 502), we examined the effects of attention during encoding on the CA relationship by reanalyzing data from a laboratory experiment in which participants viewed a stimulus video under full or divided attention conditions and then attempted to identify two targets from separate lineups. Across both studies, all three manipulations affected identification accuracy. The central analyses concerned the CA relation for positive identification decisions. For the manipulations of exposure duration and retention interval, overconfidence was greater in the more difficult conditions (shorter exposure; delayed testing) than the easier conditions. Only the exposure duration manipulation influenced resolution (which was better for 5 s than 90 s), and only the retention interval manipulation affected calibration (which was better for immediate testing than delayed testing). In all experimental conditions, accuracy and diagnosticity increased with confidence, particularly at the upper end of the confidence scale. Implications for theory and forensic settings are discussed.

  15. 12 CFR 609.945 - Records retention.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Records retention. 609.945 Section 609.945 Banks and Banking FARM CREDIT ADMINISTRATION FARM CREDIT SYSTEM ELECTRONIC COMMERCE Standards for Boards and Management § 609.945 Records retention. Records stored electronically must be accurate, accessible...

  16. African Retentions in Blues and Jazz.

    Science.gov (United States)

    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)

  17. Emotional Intelligence and Nursing Student Retention

    Science.gov (United States)

    Wilson, Victoria Jane

    2013-01-01

    The study examined the constructs of a Multi-Intelligence Model of Retention with four constructs: cognitive and emotional-social intelligence, student characteristics, and environmental factors. Data were obtained from sophomore students entering two diploma, nine associate, and five baccalaureate nursing programs. One year later, retention and


  18. Retention of high-potential employees in a development finance company

    Directory of Open Access Journals (Sweden)

    Lishani Letchmiah

    2017-09-01

    Full Text Available Orientation: The loss of high-potential employees was a concern to leaders at a South African development finance company. The research question that guided the study was: How can high-potential employees be retained in the company? Research purpose: The objective of the study was to identify factors that positively impact the retention of high-potential employees in a development finance company. Motivation for the study: The organisation that comprised the unit of study had prioritised employee development to retain high-potential employees, thereby aiming to build a strong talent pipeline and a sustainable knowledge base. A prevalent concern was that there were no formal retention programmes for high-potential employees. Accordingly, organisational leaders could benefit from understanding those retention factors that may serve to retain such employees. Research design, approach and method: A qualitative methodology promoted a deeper understanding of a social problem through a case study. Eleven purposefully chosen highpotential employees provided insights into factors they considered to be important in their retention. A content analysis of the data resulted in clusters of themes that addressed the research objective. Main findings: The following factors appeared to influence the retention of high-potential employees: leadership and organisational culture, organisational purpose, developmental opportunities, meaningful work and collegiality. Practical and managerial implications: Leaders in the company should consider factors that could influence the retention of high-potential employees. Such factors should be built into formal retention strategies based on the intrinsic needs of employees; the strengths that the organisational culture provides could be leveraged in this regard. Contribution: The practical value of the study was the highlighting of the factors that can be leveraged to retain high-potential employees in a development finance

  19. Climax granite test results

    Energy Technology Data Exchange (ETDEWEB)

    Ramspott, L.D.

    1980-01-15

    The Lawrence Livermore Laboratory (LLL), as part of the Nevada Nuclear Waste Storage Investigations (NNWSI) program, is carrying out in situ rock mechanics testing in the Climax granitic stock at the Nevada Test Site (NTS). This summary addresses only those field data taken to date that address thermomechanical modeling for a hard-rock repository. The results to be discussed include thermal measurements in a heater test that was conducted from October 1977 through July 1978, and stress and displacement measurements made during and after excavation of the canister storage drift for the Spent Fuel Test (SFT) in the Climax granite. Associated laboratory and field measurements are summarized. The rock temperature for a given applied heat load at a point in time and space can be adequately modeled with simple analytic calculations involving superposition and integration of numerous point source solutions. The input, for locations beyond about a meter from the source, can be a constant thermal conductivity and diffusivity. The value of thermal conductivity required to match the field data is as much as 25% different from laboratory-measured values. Therefore, unless we come to understand the mechanisms for this difference, a simple in situ test will be required to obtain a value for final repository design. Some sensitivity calculations have shown that the temperature field is about ten times more sensitive to conductivity than to diffusivity under the test conditions. The orthogonal array was designed to detect anisotropy. After considering all error sources, anisotropic efforts in the thermal field were less than 5 to 10%.

  20. Evaluation of a Low-Threshold/High-Tolerance Methadone Maintenance Treatment Clinic in Saint John, New Brunswick, Canada: One Year Retention Rate and Illicit Drug Use

    Directory of Open Access Journals (Sweden)

    Timothy K. S. Christie

    2013-01-01

    Full Text Available Objective. To report the one-year retention rate and the prevalence of illicit opioid use and cocaine use in the Low-Threshold/High-Tolerance (LTHT methadone maintenance treatment (MMT clinic located in Saint John, New Brunswick, Canada. Methods. A description of the LTHT MMT clinic is provided. The one-year retention rate was determined by collecting data on patients who enrolled in the LTHT MMT clinic between August 04, 2009 and August 04, 2010. The prevalence of illicit drug use was determined using a randomly selected retrospective cohort of 84 participants. For each participant the results of six consecutive urine tests for the most recent three months were compared to the results of the first six consecutive urine tests after program entry. Results. The one-year retention rate was 95%, 67% of the cohort achieved abstinence from illicit opioids and an additional 13% abstained from cocaine use. Conclusion. The novel feature of the LTHT MMT clinic is that patients are not denied methadone because of lack of ancillary services. Traditional comprehensive MMT programs invest the majority of financial resources in ancillary services that support the biopsychosocial model, whereas the LTHT approach utilizes a medical model and directs resources at medical management.

  1. Urinary Retention

    Science.gov (United States)

    ... 2011. [4] Mevcha A, Drake MJ. Etiology and management of urinary retention in women. Indian Journal of Urology. 2010;26(2):230–235. August ... 30 a.m. to 5 p.m. eastern time, M-F Follow Us NIH
 Turning Discovery Into ... Disease Urologic Diseases Endocrine Diseases Diet & Nutrition ...

  2. Retention of airborne particles in granular bed filters

    International Nuclear Information System (INIS)

    Stroem, L.

    1981-01-01

    A literature survey was made on theoretical models for the prediction of particle retention in sand beds. Also data on observed retention was collected from the literature. Based on this information, a semi-empirical model was compiled. Comparison of the model with published retention data shows a general agreement. (Auth.)

  3. Role of male partner involvement in ART retention and adherence in Malawi's Option B+ program.

    Science.gov (United States)

    Wesevich, Austin; Mtande, Tiwonge; Saidi, Friday; Cromwell, Elizabeth; Tweya, Hannock; Hosseinipour, Mina C; Hoffman, Irving; Miller, William C; Rosenberg, Nora E

    2017-11-01

    Malawi's Option B+ program provides all HIV-infected pregnant women free lifelong antiretroviral therapy (ART), but challenges remain regarding retention and ART adherence, potentially due to male partner barriers. We explored relationships between male partner involvement and Option B+ retention and adherence. In 2014, a randomized controlled trial in Malawi compared male recruitment strategies for couple HIV testing and counseling (cHTC) at an antenatal clinic. This secondary analysis was conducted among the entire cohort (N = 200) of women, irrespective of randomization status. We assessed whether cHTC attendance, early disclosure of HIV-positive status, and partner ART reminders were associated with retention and adherence at one month after starting treatment. Retention was defined as attending HIV clinic follow-up within one day of running out of pills. Adherence was defined as taking ≄95% of ARTs by pill count. We used binomial regression to calculate adjusted risk ratios (aRR) and 95% confidence intervals (CI). Median female age was 26 years. Most women (79%) were retained; of these, 68% were adherent. Receiving cHTC was associated with improved retention (aRR 1.33, 95% CI 1.12, 1.59). Receiving male partner ART reminders was weakly associated with retention (aRR 1.16, 95% CI 0.96, 1.39). Disclosure within one day was not associated with retention (aRR 1.08, 95% CI: 0.91, 1.28). Among those who were retained, these three behaviors were not associated with improved 95% adherence. CHTC could play an important role in improving Option B+ retention. Increasing cHTC participation and enhancing adherence-related messages within cHTC are important.

  4. Evaluation of Data Retention and Imprint Characteristics of FRAMs Under Environmental Stresses for NASA Applications

    Science.gov (United States)

    Sharma, Asbok K.; Teverovsky, Alexander; Dowdy, Terry W.; Hamilton, Brett

    2002-01-01

    A major reliability issue for all advanced nonvolatile memory (NVM) technology devices including FRAMs is the data retention characteristics over extended period of time, under environmental stresses and exposure to total ionizing dose (TID) radiation effects. For this testing, 256 Kb FRAMs in 28-pin plastic DIPS, rated for industrial grade temperature range of -40 C to +85 C, were procured. These are two-transistor, two-capacitor (2T-2C) design FRAMs. In addition to data retention characteristics, the parts were also evaluated for imprint failures, which are defined as the failure of cells to change from a "preferred" state, where it has been for a significant period of time to an opposite state (e.g., from 1 to 0, or 0 to 1). These 256 K FRAMs were subjected to scanning acoustic microscopy (C-SAM); 1,000 temperature cycles from -65 C to +150 C; high temperature aging at 150 C, 175 C, and 200 C for 1,000 hours; highly accelerated stress test (HAST) for 500 hours; 1,000 hours of operational life test at 125 C; and total ionizing dose radiation testing. As a preconditioning, 10 K read/write cycles were performed on all devices. Interim electrical measurements were performed throughout this characterization, including special imprint testing and final electrical testing. Some failures were observed during high temperature aging test at 200 C, during HAST testing, and during 1,000 hours of operational life at 125 C. The parts passed 10 Krad exposure, but began showing power supply current increases during the dose increment from 10 Krad to 30 Krad, and at 40 Krad severe data retention and parametric failures were observed. Failures from various environmental group testing are currently being analyzed.

  5. Abnormal Cervical Cancer Screening Test Results

    Science.gov (United States)

    ... AQ FREQUENTLY ASKED QUESTIONS FAQ187 GYNECOLOGIC PROBLEMS Abnormal Cervical Cancer Screening Test Results ‱ What is cervical cancer screening? ‱ What causes abnormal cervical cancer screening test ...

  6. Effect of air-abrasion on the retention of zirconia ceramic crowns luted with different cements before and after artificial aging.

    Science.gov (United States)

    Shahin, Ramez; Kern, Matthias

    2010-09-01

    The purpose of this in vitro study was to evaluate the effect of intaglio surface air-abrasion on the retention of CAD/CAM produced zirconia ceramic crowns cemented with three different types of cement. In addition the influence of artificial aging in masticatory simulator and thermocycling was tested. Extracted human premolars were prepared for all-ceramic crowns (12 degrees taper, 3 mm axial length). CAD/CAM zirconia crowns were manufactured. Half of the crowns were air-abraded with 50 microm alumina particles at 0.25 MPa, the rest was left as machined. The crowns were luted with zinc phosphate cement (Hoffmann), glass ionomer cement (Ketac Cem), or composite resin (Panavia 21), subgroups were either stored for 3 days in 37 degrees water bath or stored for 150 days in 37 degrees water bath, with additional 37,500 thermal cycles (5-55 degrees) and 300,000 cycles dynamic loading with 5 kg in a masticatory simulator. Then crown retention was measured in tension at a crosshead speed of 2 mm/min using a universal testing machine. Statistical analysis was performed with three-way ANOVA. Mean retention values were ranged from 2.8 to 7.1 MPa after 3 days and from 1.6 to 6.1 MPa after artificial aging. Air-abrasion significantly increased crown retention (partificial aging decreased retention (p=0.017). In addition, the luting material had a significant influence on retention (p<0.001) with the adhesive luting resin providing the highest retention. The use of phosphate monomer containing composite resin on air-abraded zirconia ceramic can be recommended as most retentive luting method. Copyright 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  7. Irradiation Effects Test Series: Test IE-3. Test results report. [PWR

    Energy Technology Data Exchange (ETDEWEB)

    Farrar, L. C.; Allison, C. M.; Croucher, D. W.; Ploger, S. A.

    1977-10-01

    The objectives of the test reported were to: (a) determine the behavior of irradiated fuel rods subjected to a rapid power increase during which the possibility of a pellet-cladding mechanical interaction failure is enhanced and (b) determine the behavior of these fuel rods during film boiling following this rapid power increase. Test IE-3 used four 0.97-m long pressurized water reactor type fuel rods fabricated from previously irradiated fuel. The fuel rods were subjected to a preconditioning period, followed by a power ramp to 69 kW/m at a coolant mass flux of 4920 kg/s-m/sup 2/. After a flow reduction to 2120 kg/s-m/sup 2/, film boiling occurred on the fuel rods. One rod failed approximately 45 seconds after the reactor was shut down as a result of cladding embrittlement due to extensive cladding oxidation. Data are presented on the behavior of these irradiated fuel rods during steady-state operation, the power ramp, and film boiling operation. The effects of a power ramp and power ramp rates on pellet-cladding interaction are discussed. Test data are compared with FRAP-T3 computer model calculations and data from a previous Irradiation Effects test in which four irradiated fuel rods of a similar design were tested. Test IE-3 results indicate that the irradiated state of the fuel rods did not significantly affect fuel rod behavior during normal, abnormal (power ramp of 20 kW/m per minute), and accident (film boiling) conditions.

  8. Chemical adhesion rather than mechanical retention enhances resin bond durability of a dental glass-ceramic with leucite crystallites

    Energy Technology Data Exchange (ETDEWEB)

    Meng, X F [Department of Prosthodontics, The Stomatological Hospital Affiliated Medical School, Nanjing University, Nanjing 210008 (China); Yoshida, K [Division of Applied Prosthodontics, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki 852-8588 (Japan); Gu, N, E-mail: mengsoar@nju.edu.c [Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096 (China)

    2010-08-01

    This study aims to evaluate the effect of chemical adhesion by a silane coupler and mechanical retention by hydrofluoric acid (HFA) etching on the bond durability of resin to a dental glass ceramic with leucite crystallites. Half of the ceramic plates were etched with 4.8% HFA (HFA group) for 60 s, and the other half were not treated (NoHFA group). The scale of their surface roughness and rough area was measured by a 3D laser scanning microscope. These plates then received one of the following two bond procedures to form four bond test groups: HFA/cement, NoHFA/cement, HFA/silane/cement and NoHFA/silane/cement. The associated micro-shear bond strength and bond failure modes were tested after 0 and 30 000 thermal water bath cycles. Four different silane/cement systems (Monobond S/Variolink II, GC Ceramic Primer/Linkmax HV, Clearfil Ceramic Primer/Clearfil Esthetic Cement and Porcelain Liner M/SuperBond C and B) were used. The data for each silane/cement system were analyzed by three-way ANOVA. HFA treatment significantly increased the surface R{sub a} and R{sub y} values and the rough area of the ceramic plates compared with NoHFA treatment. After 30 000 thermal water bath cycles, the bond strength of all the test groups except the HFA/Linkmax HV group was significantly reduced, while the HFA/Linkmax HV group showed only adhesive interface failure. The other HFA/cement groups and all NoHFA/cement groups lost bond strength completely, and all NoHFA/silane/cement groups with chemical adhesion had significantly higher bond strength and more ceramic cohesive failures than the respective HFA/cement groups with mechanical retention. The result of the HFA/silane/cement groups with both chemical adhesion and mechanical retention revealed that HFA treatment could enhance the bond durability of resin/silanized glass ceramics, which might result from the increase of the chemical adhesion area on the ceramic rough surface and subsequently reduced degradation speed of the silane

  9. Black Student Retention in Higher Education.

    Science.gov (United States)

    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,


  10. Minority Teacher Recruitment and Retention Strategies

    Science.gov (United States)

    Kearney-Gissendaner, Janet E.

    2010-01-01

    The tools and resources in this book help school leaders seamlessly incorporate minority teacher recruitment and retention programs into current human-resources activities. With details about exemplary minority teacher recruitment and retention programs, this book also showcases strategies for how to replicate such programs in your own school or


  11. Effects of training on short- and long-term skill retention in a complex multiple-task environment.

    Science.gov (United States)

    Sauer, J; Hockey, G R; Wastell, D G

    2000-12-01

    The paper reports the results of an experiment on the performance and retention of a complex task. This was a computer-based simulation of the essential elements of a spacecraft's life support system. It allowed the authors to take a range of measures, including primary and secondary task performance, system intervention and information sampling strategies, mental model structure, and subjective operator state. The study compared the effectiveness of two methods of training, based on low level (procedure-based) and high level (system-based) understanding. Twenty-five participants were trained extensively on the task, then given a 1-h testing session. A second testing session was carried out 8 months after the first (with no intervening practice) with 17 of the original participants. While training had little effect on control performance, there were considerable effects on system management strategies, as well as in structure of operator's mental model. In the second testing session, the anticipated general performance decrement did not occur, though for complex faults there was an increase in selectivity towards the primary control task. The relevance of the findings for training and skill retention in real work environments is discussed in the context of a model of compensatory control.

  12. The PSI Artist Project: Aerosol Retention and Accident Management Issues Following a Steam Generator Tube Rupture

    International Nuclear Information System (INIS)

    Guntay, Salih; Dehbi, Abdel; Suckow, Detlef; Birchley, Jon

    2002-01-01

    Steam generator tube rupture (SGTR) incidents, such as those, which occurred in various operating pressurized, water reactors in the past, are serious operational concerns and remain among the most risk-dominant events. Although considerable efforts have been spent to understand tube degradation processes, develop improved modes of operation, and take preventative and corrective measures, SGTR incidents cannot be completely ruled out. Under certain conditions, high releases of radionuclides to the environment are possible during design basis accidents (DBA) and severe accidents. The severe accident codes' models for aerosol retention in the secondary side of a steam generator (SG) have not been assessed against any experimental data, which means that the uncertainties in the source term following an un-isolated SGTR concurrent with a severe accident are not currently quantified. The accident management (AM) procedures aim at avoiding or minimizing the release of fission products from the SG. The enhanced retention of activity within the SG defines the effectiveness of the accident management actions for the specific hardware characteristics and accident conditions of concern. A sound database on aerosol retention due to natural processes in the SG is not available, nor is an assessment of the effect of management actions on these processes. Hence, the effectiveness of the AM in SGTR events is not presently known. To help reduce uncertainties relating to SGTR issues, an experimental project, ARTIST (Aerosol Trapping In a Steam generator), has been initiated at the Paul Scherrer Institut to address aerosol and droplet retention in the various parts of the SG. The test section is comprised of a scaled-down tube bundle, a full-size separator and a full-size dryer unit. The project will study phenomena at the separate effect and integral levels and address AM issues in seven distinct phases: Aerosol retention in 1) the broken tube under dry secondary side conditions, 2

  13. Testing the larval drift hypothesis in the Baltic Sea: retention versus dispersion caused by wind-driven circulation

    DEFF Research Database (Denmark)

    Hinrichsen, H.H.; St. John, Michael; Aro, E.

    2001-01-01

    Retention or dispersion of larvae from the spawning grounds has been identified as one of the key processes influencing recruitment success in fish stocks. To examine the potential effects of transport on recruitment. numerical simulations were performed utilizing a three-dimensional physical oce...

  14. Dense understory dwarf bamboo alters the retention of canopy tree seeds

    Science.gov (United States)

    Qian, Feng; Zhang, Tengda; Guo, Qinxue; Tao, Jianping

    2016-05-01

    Tree seed retention is thought to be an important factor in the process of forest community regeneration. Although dense understory dwarf bamboo has been considered to have serious negative effects on the regeneration of forest community species, little attention has been paid to the relationship between dwarf bamboo and seed retention. In a field experiment we manipulated the density of Fargesia decurvata, a common understory dwarf bamboo, to investigate the retention of seeds from five canopy tree species in an evergreen and deciduous broad-leaved mixed forest in Jinfoshan National Nature Reserve, SW China. We found that the median survival time and retention ratio of seeds increased with the increase in bamboo density. Fauna discriminately altered seed retention in bamboo groves of different densities. Arthropods reduced seed survival the most, and seeds removed decreased with increasing bamboo density. Birds removed or ate more seeds in groves of medium bamboo density and consumed fewer seeds in dense or sparse bamboo habitats. Rodents removed a greater number of large and highly profitable seeds in dense bamboo groves but more small and thin-husked seeds in sparse bamboo groves. Seed characteristics, including seed size, seed mass and seed profitability, were important factors affecting seed retention. The results suggested that dense understory dwarf bamboo not only increased seeds concealment and reduced the probability and speed of seed removal but also influenced the trade-off between predation and risk of animal predatory strategies, thereby impacting the quantity and composition of surviving seeds. Our results also indicated that dense understory dwarf bamboo and various seed characteristics can provide good opportunities for seed storage and seed germination and has a potential positive effect on canopy tree regeneration.

  15. Strategies to enhance participant recruitment and retention in research involving a community-based population.

    Science.gov (United States)

    McCullagh, Marjorie C; Sanon, Marie-Anne; Cohen, Michael A

    2014-11-01

    Challenges associated with recruiting and retaining community-based populations in research studies have been recognized yet remain of major concern for researchers. There is a need for exchange of recruitment and retention techniques that inform recruitment and retention strategies. Here, the authors discuss a variety of methods that were successful in exceeding target recruitment and retention goals in a randomized clinical trial of hearing protector use among farm operators. Recruitment and retention strategies were 1) based on a philosophy of mutually beneficial engagement in the research process, 2) culturally appropriate, 3) tailored to the unique needs of partnering agencies, and 4) developed and refined in a cyclical and iterative process. Sponsoring organizations are interested in cost-effective recruitment and retention strategies, particularly relating to culturally and ethnically diverse groups. These approaches may result in enhanced subject recruitment and retention, concomitant containment of study costs, and timely accomplishment of study aims. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. 76 FR 34010 - Credit Risk Retention

    Science.gov (United States)

    2011-06-10

    ... 2501-AD53 Credit Risk Retention AGENCIES: Office of the Comptroller of the Currency, Treasury (OCC... credit risk retention requirements of section 15G of the Securities Exchange Act of 1934, as added by the Dodd-Frank Wall Street Reform and Consumer Protection Act (``Credit Risk NPR'' or ``proposed rule...

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

    Science.gov (United States)

    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


  18. Dopamine antagonists during parturition disrupt maternal care and the retention of maternal behavior in rats.

    Science.gov (United States)

    Byrnes, Elizabeth M; Rigero, Beth A; Bridges, Robert S

    2002-11-01

    Brief contact with pups at parturition enables the female rat to establish and retain the full repertoire of maternal behaviors, allowing her to respond rapidly to pups in the future. To determine whether the dopamine system is involved in the retention of maternal behavior, females were continuously infused with dopamine antagonists during the periparturitional period and then allowed either a brief interaction period with pups (3 h) or no interaction with pups (pups removed as they were born). Females were exposed to either the D1-like antagonist SCH 23390 (0.1 or 1.0 mg/kg/day) or the D2-like antagonist clebopride (0.5 or 1.0 mg/kg/day). The high dose of either DA antagonist resulted in significant attenuation of maternal care immediately postpartum. When tested for the retention of maternal behavior 7 days later, however, only the females exposed to the D2 antagonist displayed a delayed response to shown full maternal behavior (FMB) towards donor pups. Thus, while both dopamine receptor subtypes appear necessary for the full and rapid expression of maternal behavior during the early postpartum period, only the D2 receptor subtype appears to be involved in the retention of this behavior.

  19. Strategy for reduced calibration sets to develop quantitative structure-retention relationships in high-performance liquid chromatography

    Energy Technology Data Exchange (ETDEWEB)

    Andries, Jan P.M. [University of Professional Education, Department of Life Sciences, P.O. Box 90116, 4800 RA Breda (Netherlands); Claessens, Henk A. [University of Professional Education, Department of Life Sciences, P.O. Box 90116, 4800 RA Breda (Netherlands); Eindhoven University of Technology, Department of Chemical Engineering and Chemistry, Laboratory of Polymer Chemistry, P.O. Box 513 (Helix, STW 1.35), 5600 MB Eindhoven (Netherlands); Heyden, Yvan Vander [Department of Analytical Chemistry and Pharmaceutical Technology, Vrije Universiteit Brussel-VUB, Laarbeeklaan 103, B-1090 Brussels (Belgium); Buydens, Lutgarde M.C., E-mail: L.Buydens@science.ru.nl [Institute for Molecules and Materials, Radboud University Nijmegen, Toernooiveld 1, 6525 ED Nijmegen (Netherlands)

    2009-10-12

    In high-performance liquid chromatography, quantitative structure-retention relationships (QSRRs) are applied to model the relation between chromatographic retention and quantities derived from molecular structure of analytes. Classically a substantial number of test analytes is used to build QSRR models. This makes their application laborious and time consuming. In this work a strategy is presented to build QSRR models based on selected reduced calibration sets. The analytes in the reduced calibration sets are selected from larger sets of analytes by applying the algorithm of Kennard and Stone on the molecular descriptors used in the QSRR concerned. The strategy was applied on three QSRR models of different complexity, relating logk{sub w} or log k with either: (i) log P, the n-octanol-water partition coefficient, (ii) calculated quantum chemical indices (QCI), or (iii) descriptors from the linear solvation energy relationship (LSER). Models were developed and validated for 76 reversed-phase high-performance liquid chromatography systems. From the results we can conclude that it is possible to develop log P models suitable for the future prediction of retentions with as few as seven analytes. For the QCI and LSER models we derived the rule that three selected analytes per descriptor are sufficient. Both the dependent variable space, formed by the retention values, and the independent variable space, formed by the descriptors, are covered well by the reduced calibration sets. Finally guidelines to construct small calibration sets are formulated.

  20. Can intra-radicular cleaning protocols increase the retention of fiberglass posts? A systematic review

    Directory of Open Access Journals (Sweden)

    Lilian Vieira OLIVEIRA

    2018-03-01

    Full Text Available Abstract The presence of residues within the root canal after post-space preparation can influence the bond strength between resin cement and root dentin when using fiberglass posts (FGPs. Currently, there is no consensus in the literature regarding what is the best solution for the removal of debris after post-space preparation. This systematic review involved “in vitro” studies to investigate if cleaning methods of the root canal after post-space preparation can increase the retention of FGPs evaluated by the push-out test. Searches were carried out in PubMed (MEDLINE and Scopus databases up to July2017. English language studies published from 2007 to July 2017 were selected. 475 studies were found, and 9 were included in this review. Information from the 9 studies were collected regarding the number of samples, storage method after extraction, root canal preparation, method of post-space preparation, endodontic sealer, resin cement, cleaning methods after post-space and presence of irrigant activation. Five studies presented the best results for the association of sodium hypochlorite (NaOCl and ethylenediamine tetra-acetic acid (EDTA, while in the other 4 studies, the solutions that showed improved retention of FGPs were photon-induced photoacoustic streaming (PIPS, Qmix, Sikko and EDTA. The results showed heterogeneity in all comparisons due to a high variety of information about cleaning methods, different concentrations, application time, type of adhesive system and resin cements used. In conclusion, this review suggests that the use of NaOCl/EDTA results in the retention of FGPs and may thus be recommended as a post-space cleaning method influencing the luting procedure.

  1. Assessing the potential contributions of additional retention processes to PFAS retardation in the subsurface.

    Science.gov (United States)

    Brusseau, Mark L

    2018-02-01

    A comprehensive understanding of the transport and fate of per- and poly-fluoroalkyl substances (PFAS) in the subsurface is critical for accurate risk assessments and design of effective remedial actions. A multi-process retention model is proposed to account for potential additional sources of retardation for PFAS transport in source zones. These include partitioning to the soil atmosphere, adsorption at air-water interfaces, partitioning to trapped organic liquids (NAPL), and adsorption at NAPL-water interfaces. An initial assessment of the relative magnitudes and significance of these retention processes was conducted for two PFAS of primary concern, perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA), and an example precursor (fluorotelomer alcohol, FTOH). The illustrative evaluation was conducted using measured porous-medium properties representative of a sandy vadose-zone soil. 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 the model system. The results showed that adsorption at the air-water interface was a primary source of retention for both PFOA and PFOS, contributing approximately 50% of total retention for the conditions employed. Adsorption to NAPL-water interfaces and partitioning to bulk NAPL were also shown to be significant sources of retention. NAPL partitioning was the predominant source of retention for FTOH, contributing ~98% of total retention. These results indicate that these additional processes may be, in some cases, significant sources of retention for subsurface transport of PFAS. The specific magnitudes and significance of the individual retention processes will depend upon the properties and conditions of the specific system of interest (e.g., PFAS constituent and concentration, porous medium, aqueous chemistry, fluid saturations, co-contaminants). In cases wherein these

  2. Interventions that promote retention of experienced registered nurses in health care settings: a systematic review.

    Science.gov (United States)

    Lartey, Sarah; Cummings, Greta; Profetto-McGrath, Joanne

    2014-11-01

    The aim of this review was to report the effectiveness of strategies for retaining experienced Registered Nurses. Nursing researchers have noted that the projected nursing shortage, if not rectified, is expected to affect healthcare cost, job satisfaction and quality patient care. Retaining experienced nurses would help to mitigate the shortage, facilitate the transfer of knowledge and provision of quality care to patients. A systematic review of studies on interventions that promote the retention of experienced Registered Nurses in health care settings. Twelve studies were included in the final analysis. Most studies reported improved retention as a result of the intervention. Team work and individually targeted strategies including mentoring, leadership interest and in-depth orientation increased job satisfaction and produced higher retention results. Few published studies have examined interventions that promote the retention of experienced Registered Nurses in healthcare. Retention was highest when multiple interventions were used. Further research is needed to inform nurse leaders of ways to retain nurses and to maintain quality care in health care settings. Programmes targeting the retention of experienced nurses need to be considered when implementing measures to decrease the nursing shortage and its effects on quality care. © 2013 John Wiley & Sons Ltd.

  3. A Model for Freshman Engineering Retention

    Science.gov (United States)

    Veenstra, Cindy P.; Dey, Eric L.; Herrin, Gary D.

    2009-01-01

    With the current concern over the growing need for more engineers, there is an immediate need to improve freshman engineering retention. A working model for freshman engineering retention is needed. This paper proposes such a model based on Tinto's Interactionalist Theory. Emphasis in this model is placed on pre-college characteristics as


  4. Relationships Between Herpetofaunal Community Structure and Varying Levels of Overstory Tree Retention in Northern Alabama: First-year Results

    Science.gov (United States)

    Zachary I. Felix; Yong Wang; Callie Jo Schweitzer

    2004-01-01

    Forest managers are increasingly considering the effects their decisions have on the biodiversity of an area. However, there is often a lack of data upon which to evaluate these decisions. We conducted research to examine the relationship between silvicultural techniques, particularly shelterwood cuts with varying levels of basal area retention, and the community...

  5. Influence of surface treatment of yttrium-stabilized tetragonal zirconium oxides and cement type on crown retention after artificial aging.

    Science.gov (United States)

    Karimipour-Saryazdi, Mehdi; Sadid-Zadeh, Ramtin; Givan, Daniel; Burgess, John O; Ramp, Lance C; Liu, Perng-Ru

    2014-05-01

    Information about the influence of zirconia crown surface treatment and cement type on the retention of zirconia crowns is limited. It is unclear whether zirconia crowns require surface treatment to enhance their retention. The purpose of this in vitro study was to evaluate the effect of surface treatment on the retention of zirconia crowns cemented with 3 different adhesive resin cements after artificial aging. Ninety extracted human molars were prepared for ceramic crowns (approximately 20-degree taper, approximately 4-mm axial length) and were divided into 3 groups (n=30). Computer-aided design and computer-aided manufacturing zirconia copings were fabricated. Three surface treatments were applied to the intaglio surface of the copings. The control group received no treatment, the second group was airborne-particle abraded with 50 Όm Al2O3, and the third group was treated with 30 Όm silica-modified Al2O3, The copings were luted with a self-etch (RelyX Unicem 2), a total-etch (Duo-Link), or a self-etch primer (Panavia F 2.0) adhesive cement. They were stored for 24 hours at 37°C before being artificially aged with 5000 (5°C-55°C) thermal cycles and 100,000 cycles of 70 N dynamic loading. Retention was measured on a universal testing machine under tension, with a crosshead speed of 0.5 mm/min. Statistical analysis was performed with 1-way and 2-way ANOVA. Mean retention values ranged from 0.72 to 3.7 MPa. Surface treatment increased crown retention, but the difference was not statistically significant (P>.05), except for the Duo-Link cement group (P<.05). Analysis of the adhesives revealed that the Duo-Link cement resulted in significantly lower crown retention (P<.05) than the other 2 cements. For zirconia crowns, retention seems to be dependent on cement type rather than surface treatment. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  6. The effect of extensive reading and paired-associate learning on long-term vocabulary retention: an event-related potential study.

    Science.gov (United States)

    Chun, Eunjin; Choi, Sungmook; Kim, Junsoo

    2012-07-19

    We investigated the relative efficacy of extensive reading (ER) and paired-associate learning (PAL) in the ability of second language (L2) learners to retain new vocabulary words. To that end, we combined behavioral measures (i.e., vocabulary tests) and an event-related potential (ERP) investigation with a focus on the N400 ERP component to track short- and long-term vocabulary retention as a consequence of the two different approaches. Behavioral results indicated that both ER and PAL led to substantial short-term retention of the target words. In contrast, on a long-term basis, ER was more effective than PAL to a considerable degree as indicated by a large-size effect (d=1.35). Evidence from the N400 effects (d=1.70) observed in the parietal electrode group (P3, Pz, P4) provided further support for the superior effects of ER over PAL on long-term vocabulary retention. The converging evidence challenges the assumptions of some L2 researchers and makes a significant contribution to the literature of vocabulary acquisition, because it provides the first ERP evidence that ER is more conducive to long-term vocabulary retention than PAL. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  7. A study on fission product retention capability in a sodium coolant system

    International Nuclear Information System (INIS)

    Satoh, K.; Kubo, S.; Hashiguchi, Y.; Itooka, S.; Akatsu, Y.; Miyagi, K.; Wakamatsu, M.; Endo, H.; Tachino, T.

    1992-01-01

    Three kinds of separate model tests have been performed using water and air, focusing on the transport behavior of FP gas bubbles from subassembly outlets into a cover gas region, to study the dominant processes regarding the retention for volatiles ejected with inert gas into sodium after fuel failures. In the case that whole fuel pin failures occurring coherently in a subassembly were assumed, a periodic formation of globules was observed at the subassembly outlet. The globules rapidly broke up into small bubbles of less than 10 mm in mean diameter. The small bubbles at the top region had a tendency to be coalesced during rising through the upper plenum. As the coolant flow rate increased, bubble deformation and breakup were accelerated, but the bubble transport time did not vary remarkably. It is expected that bubbles in sodium would play in a similar way as in the water test, and the importance of the bubble behavior for the retention capability of volatiles has been confirmed. (author)

  8. Metaphorical Awareness: A New Horizon in Vocabulary Retention by Asian EFL Learners

    Directory of Open Access Journals (Sweden)

    Natasha Pourdana

    2014-07-01

    Full Text Available The present study investigates the impact of English metaphorical awareness on the vocabulary retention by 60 intermediate EFL learners in Iran. Participants in this study were all English as a Foreign language (EFL learners placed in the intermediate level of both genders ranging from 16 to 20 years of age at Qeshm language institute, Kerman, Iran. An Oxford Placement Test (OPT was administered to homogenize the participants and divided them into two intact experimental and control groups. The experimental group was exposed to and performed on 20 minutes English metaphorical awareness tasks of Pictorial Idioms, Poems, and Matching in sixteen 90-minute sessions. The controllgroup received the vocabulary exercises in New Cutting Edge (3rd Edition (Cunningham, Moor & Eales 2007 in turn The experimental group outperformed the controlgroup in this study.  In an independent sample t-Test, and a high effect size (Cohn’s d=2.84 supported the positive impact of metaphorical awareness on EFL learners' vocabulary retention.

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

    Directory of Open Access Journals (Sweden)

    Janet M Box-Steffensmeier

    Full Text Available 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.

  10. BWR Full Integral Simulation Test (FIST). Phase I test results

    International Nuclear Information System (INIS)

    Hwang, W.S.; Alamgir, M.; Sutherland, W.A.

    1984-09-01

    A new full height BWR system simulator has been built under the Full-Integral-Simulation-Test (FIST) program to investigate the system responses to various transients. The test program consists of two test phases. This report provides a summary, discussions, highlights and conclusions of the FIST Phase I tests. Eight matrix tests were conducted in the FIST Phase I. These tests have investigated the large break, small break and steamline break LOCA's, as well as natural circulation and power transients. Results and governing phenomena of each test have been evaluated and discussed in detail in this report. One of the FIST program objectives is to assess the TRAC code by comparisons with test data. Two pretest predictions made with TRACB02 are presented and compared with test data in this report

  11. NONEQUILIBRIUM SULFUR CAPTURE AND RETENTION IN AN AIR COOLED SLAGGING COAL COMBUSTOR

    International Nuclear Information System (INIS)

    Dr. Bert Zauderer

    1999-01-01

    Calcium oxide injected in a slagging combustor reacts with the sulfur from coal combustion to form sulfur-bearing particles. They are deposited on the liquid slag layer on the combustor wall. Due to the low solubility of sulfur in slag, slag must be rapidly drained from the combustor to limit sulfur gas re-evolution. Analysis indicated that slag mass flow rates in excess of 400 lb/hr should limit sulfur re-evolution. The objective of this 42-month project was to perform a series of tests to determine the factors that control the retention of the sulfur in the slag. 36 days of testing on the combustor were completed prior to the end of this reporting period, 12/31/98. This compares with 16 tests required in the original project plan. Combustor tests in early 1997 with high (37%) ash, Indian coal confirmed that high slag mass flow rates of about 500 lb/hr resulted in retention in the slag of up to 20% of the injected sulfur content mineral matter. To further increase the slag flow rate, rice husks, which contain 20% ash, and rice husk char, which contain 70% ash, were co-fired with coal in the combustor. A series of 13 combustor tests were performed in fourth quarter of 1997 and a further 6 tests were performed in January 1998 and in the summer of 1998. The test objective was to achieve slag flow rates between 500 and 1,000 lb/hr. Due to the very low bulk density of rice husk, compared to pulverized coal, almost the entire test effort focused on developing methods for feeding the rice husks into combustor. In the last test of December 1997, a peak mineral matter, injection rate of 592 lb/hr was briefly achieved by injection of coal, rice husk char, gypsum, and limestone into the combustor. However, no significant sulfur concentration was measured in the slag removed from the combustor. The peak injection rate reached with biomass in the 1997 tests was 310 lb/hr with rice husk, and 584 lb/hr with rice husk char

  12. Mucous retention cyst of the maxillary sinus.

    Science.gov (United States)

    Ruprecht, A; Batniji, S; el-Neweihi, E

    1986-12-01

    The mucous retention cyst is not a rare phenomenon. The incidence of dental patients was determined. Of 1685 patient radiographs reviewed, 44 (2.6%) had one or more mucous retention cysts in the maxillary sinuses.

  13. [Study on retention and stability of linear occlusal complete dentures].

    Science.gov (United States)

    Zhang, Ping; Xu, Jun

    2003-01-01

    To learn retention and stability of linear occlusal complete dentures by investigating the subjective feelings of patient and the value of retention force. Static retention forces of maxillary and mandibular dentures were measured for 25 patients wearing linear occlusal dentures by using Hz-1 retention dynamometer. The subjective feelings of patients in functional state were gained simultaneously through questionnaire. Linear occlusal dentures demonstrate good retention in static and dynamic state. Among patients with severe resorption of residual ridge (RRR), mandibular linear occlusal dentures (shown good retentive subjective feelings) demonstrate significantly smaller retention force than those with slight or medium degree of RRR. There is no correlation between the subjective feelings and the values of retention forces of mandibular dentures. The subjective feelings of patients wearing new linear occlusal dentures are much better than that of old anatomic occlusal dentures. Linear occlusal dentures improve the performances of dentures by enhancing their stability during mastication movement.

  14. Whole body retention of Se-75-homotaurocholic acid (SeBCAT) using a Gamma Camera: A new test in chronic diarrhea

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, H.; Palma, R.; Pfau, J.; Coudeu, I.; Bauer, K.

    1985-05-01

    Bile acid malabsorption has been recognized as an important cause of chronic diarrhea. Se-75HCAT, a bile acid, is absorbed in the terminal ileum. Therefore, measurement of its body retention indicate ileal function not requiring fecal collections. The authors studied 8 normal volunteers presenting with chronic recurrent diarrhea for more than 2 years. Each received orally a 10 ..mu..Ci capsule of SeHCAT (Amersham Intl.) and 3 hours later anterior and posterior whole body activity was measured using a digital camera without collimator. Measurements were repeated daily for 7 days and expressed as % of retention. Three patients had normal retention (1 celiac disease, 1 inactive Crohn disease and 1 functional diarrhea), another was borderline (an immunodeficiency) and 4 patients presented abnormal bile acid absorption (2 had vagotomy, 1 Crohn disease and 1 idiopathic diarrhea). This last group was treated with cholestyramine showing improvement of the diarrhea, and relapse on drug withdrawal. These findings demonstrate that this technique can identify bile acid malabsorption as the cause of chronic diarrhea by external counting.

  15. Whole body retention of Se-75-homotaurocholic acid (SeBCAT) using a Gamma Camera: A new test in chronic diarrhea

    International Nuclear Information System (INIS)

    Amaral, H.; Palma, R.; Pfau, J.; Coudeu, I.; Bauer, K.

    1985-01-01

    Bile acid malabsorption has been recognized as an important cause of chronic diarrhea. Se-75HCAT, a bile acid, is absorbed in the terminal ileum. Therefore, measurement of its body retention indicate ileal function not requiring fecal collections. The authors studied 8 normal volunteers presenting with chronic recurrent diarrhea for more than 2 years. Each received orally a 10 ÎŒCi capsule of SeHCAT (Amersham Intl.) and 3 hours later anterior and posterior whole body activity was measured using a digital camera without collimator. Measurements were repeated daily for 7 days and expressed as % of retention. Three patients had normal retention (1 celiac disease, 1 inactive Crohn disease and 1 functional diarrhea), another was borderline (an immunodeficiency) and 4 patients presented abnormal bile acid absorption (2 had vagotomy, 1 Crohn disease and 1 idiopathic diarrhea). This last group was treated with cholestyramine showing improvement of the diarrhea, and relapse on drug withdrawal. These findings demonstrate that this technique can identify bile acid malabsorption as the cause of chronic diarrhea by external counting

  16. Effects of Hydrocarbon-Based Grease on Rapid Prototype Material Used for Grease Retention Shrouds

    Science.gov (United States)

    Zakrajsek, Andrew J.; Valco, Daniel J.; Street, Kenneth W., Jr.

    2010-01-01

    Effects of hydrocarbon-based greases on specific rapid prototype (RP) materials used to fabricate grease retention shrouds (GRS) were explored in this study. Grease retention shrouds are being considered as a way to maintain adequate grease lubrication at the gear mesh in a prototype research transmission system. Due to their design and manufacturing flexibility, rapid prototype materials were chosen for the grease retention shrouds. In order to gain a better understanding of the short and long term effects grease pose on RP materials, research was conducted on the interaction of hydrocarbon-based grease with RP materials. The materials used in this study were durable polyamide (nylon), acrylonitrile butadiene styrene (ABS), and WaterClear 10120. Testing was conducted using Mobilgrease 28 and Syn-Tech 3913G grease (gear coupling grease). These greases were selected due to their regular use with mechanical components. To investigate the effect that grease has on RP materials, the following methods were used to obtain qualitative and quantitative data: Fourier transform infrared spectroscopy (FT-IR), interference profilometer measurements, digital camera imaging, physical shape measurement, and visual observations. To record the changes in the RP materials due to contact with the grease, data was taken before and after the grease application. Results showed that the WaterClear 10120 RP material provided the best resistance to grease penetration as compared to nylon and ABS RP materials. The manufacturing process, and thus resulting surface conditions of the RP material, played a key role in the grease penetration properties and resilience of these materials.

  17. Evaluations of Mechanisms for Pu Uptake and Retention within Spherical Resorcinol-Formaldehyde Resin Columns

    Energy Technology Data Exchange (ETDEWEB)

    Delegard, Calvin H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Levitskaia, Tatiana G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fiskum, Sandra K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-15

    The unexpected uptake and retention of plutonium (Pu) onto columns containing spherical resorcinol-formaldehyde (sRF) resin during ion exchange testing of Cs (Cs) removal from alkaline tank waste was observed in experiments at both the Pacific Northwest National Laboratory (PNNL) and the Savannah River National Laboratory (SRNL). These observations have raised concern regarding the criticality safety of the Cs removal unit operation within the low-activity waste pretreatment system (LAWPS). Accordingly, studies have been initiated at Washington River Protection Solutions (WRPS), who manages the operations of the Hanford Site tank farms, including the LAWPS, PNNL, and elsewhere to investigate these findings. As part of these efforts, PNNL has prepared the present report to summarize the laboratory testing observations, evaluate these phenomena in light of published and unpublished technical information, and outline future laboratory testing, as deemed appropriate based on the literature studies, with the goal to elucidate the mechanisms for the observed Pu uptake and retention.

  18. Temporal determinants of long-term retention of olfactory memory in the cricket Gryllus bimaculatus.

    Science.gov (United States)

    Matsumoto, Yukihisa; Mizunami, Makoto

    2002-05-01

    Temporal determinants of olfactory long-term memory retention in the cricket Gryllus bimaculatus were studied. Elementary appetitive and aversive conditioning procedures, as well as a differential conditioning procedure, were applied. In appetitive conditioning, peppermint odour was paired with a water reward. In aversive conditioning, vanilla odour was paired with saline solution. In differential conditioning, an appetitive conditioning trial was followed by an aversive conditioning trial. The odour preference of crickets was tested before and 2 h, 1 day and 4 days after training by allowing the crickets to choose between peppermint or vanilla sources. Differential conditioning or appetitive conditioning alone led to long-lasting memory retention with no significant decay from 2 h to 4 days after training, but retention after aversive conditioning was absent 1 day after training. Studies using differential conditioning have shown (i) that four trials are sufficient to cause a saturated level of acquisition, (ii) that conditioning is successful when the conditioned stimulus is presented immediately or 5 s before the onset of presentation of the unconditioned stimulus, (iii) that the optimal interval between trials is 2-5 min, and (iv) that anaesthetic treatment with CO2 given immediately after training results in memory disruption but that anaesthetic-resistant memory develops fully 20 min after training. This study demonstrates that a differential conditioning procedure is particularly effective for the formation of long-term memory.

  19. Consideration of Cosmetic Surgery As Part of Women's Benefit-Provisioning Mate Retention Strategy.

    Science.gov (United States)

    Atari, Mohammad; Barbaro, Nicole; Sela, Yael; Shackelford, Todd K; Chegeni, Razieh

    2017-01-01

    Individuals perform mate retention behaviors to minimize the risk of partner infidelity and relationship dissolution. The current study investigates whether consideration of cosmetic surgery can be conceptualized as part of a broader strategy of mate retention for women, but not men. We hypothesized that women's consideration of cosmetic surgery would be positively associated with performance frequencies of Benefit-Provisioning and Cost-Inflicting mate retention behaviors. We recruited 203 individuals (54% women) in committed heterosexual relationships from Tehran, Iran. Results indicate a positive association between consideration of cosmetic surgery and Benefit-Provisioning mate retention behaviors for women, but not men. There was no association between consideration of cosmetic surgery and Cost-Inflicting mate retention behaviors. Women therefore may consider cosmetic surgery to improve their physical attractiveness as part of a Benefit-Provisioning strategy to retain a long-term mate. We discuss limitations of the study and highlight future directions for research from an evolutionary perspective.

  20. The effectiveness of adhesives on the retention of mandibular free end saddle partial dentures: An in vitro study.

    Science.gov (United States)

    Quiney, Daniel; Nishio Ayre, Wayne; Milward, Paul

    2017-07-01

    Existing in vitro methods for testing denture adhesives do not fully replicate the complex oral geometries and environment; and in vivo methods are qualitative, prone to bias and not easily reproducible. The purpose of this study was to develop a novel, quantitative and more accurate model to test the effect of adhesives on the retentive force of mandibular free end saddle partial dentures. An in vitro model was developed based on an anatomically accurate cast of a clinical case. Experimentally, the amount of adhesive was varied (0.2g-1g) and the tensile force required for displacement was measured. Different commercially available adhesives were then tested at the optimum volume using the in vitro model. A 3D finite element model of the denture was used to assess how the forces to induce denture displacement varied according to the position of the force along the saddle length. The mass of adhesive was found to significantly alter retention forces, with 0.4-0.7g being the optimum range for this particular scenario. Use of adhesives significantly improved mandibular free end saddle partial denture retention with the worst performing adhesive increasing retention nine-fold whilst the best performing adhesive increased retention twenty three-fold. The finite element model revealed that 77% more force was required to displace the denture by positioning forces towards the mesial end of the saddle compared to the distal end. An in vitro denture adhesive model was developed, which demonstrated that mass of adhesive plays a significant role in enhancing denture retention and supported the design principle of placing as few teeth as clinically necessary on the distal end of the free end saddles. Limiting the position of teeth on free end saddles to the mesial and mid portion of the saddle will reduce displacements caused by mastication. The movement of mandibular free end saddle partial dentures can be restricted with the use of denture adhesives. Altering the mass of

  1. Collaborative testing as a learning strategy in nursing education.

    Science.gov (United States)

    Sandahl, Sheryl S

    2010-01-01

    A primary goal of nursing education is to prepare nurses to work collaboratively as members of interprofessional health care teams on behalf of patients. Collaborative testing is a collaborative learning strategy used to foster knowledge development, critical thinking in decision making, and group processing skills. This study incorporated a quasi-experimental design with a comparison group to examine the effect of collaborative testing as a learning strategy on student learning and retention of course content as well as group process skills and student perceptions of their learning and anxiety. The setting was a baccalaureate nursing program; the sample consisted of two groups of senior students enrolled in Medical-Surgical Nursing II. Student learning, as measured by unit examination scores, was greater for students taking examinations collaboratively compared to individually. Retention of course content, as measured by final examination scores, was not greater for students taking examinations collaboratively compared to individually. Student perceptions were overwhelmingly positive, with students reporting increased learning as a result of the collaborative testing experiences. Despite the lack of data to support increased retention, collaborative testing may be a learning strategy worth implementing in nursing education. Students reported more positive interactions and collaboration with their peers, skills required by the professional nurse.

  2. Addressing employee turnover and retention: keeping your valued performers.

    Science.gov (United States)

    McConnell, Charles R

    2011-01-01

    Employee turnover and employee retention are inextricably linked; to control turnover is to enhance retention. Turnover is a relatively simple concept; however, considerable confusion often results when addressing turnover because of differences in how it is defined; that is, what is counted, how it is counted, and how the turnover rates are expressed. Turnover is also costly, although not enough attention is paid to its cost because so much of it is indirect and thus not readily visible. There are a variety of causes of turnover, some that can be corrected and some that cannot be avoided. Reducing or otherwise controlling turnover requires continuing management attention to its causes and constant recognition of what can and should be controlled and what cannot be controlled. Ongoing attention to turnover is an essential part of the department manager's role; every improvement in turnover is a direct improvement in retention, with eventual positive effects on the bottom line.

  3. Results of steel containment vessel model test

    International Nuclear Information System (INIS)

    Luk, V.K.; Ludwigsen, J.S.; Hessheimer, M.F.; Komine, Kuniaki; Matsumoto, Tomoyuki; Costello, J.F.

    1998-05-01

    A series of static overpressurization tests of scale models of nuclear containment structures is being conducted by Sandia National Laboratories for the Nuclear Power Engineering Corporation of Japan and the US Nuclear Regulatory Commission. Two tests are being conducted: (1) a test of a model of a steel containment vessel (SCV) and (2) a test of a model of a prestressed concrete containment vessel (PCCV). This paper summarizes the conduct of the high pressure pneumatic test of the SCV model and the results of that test. Results of this test are summarized and are compared with pretest predictions performed by the sponsoring organizations and others who participated in a blind pretest prediction effort. Questions raised by this comparison are identified and plans for posttest analysis are discussed

  4. Plaque retention on elastomeric ligatures. An in vivo study

    OpenAIRE

    CONDÒ, R.; CASAGLIA, A.; CONDÒ, S.G.; CERRONI, L.

    2013-01-01

    Fixed orthodontic appliances make it difficult to maintain the oral hygiene, resulting in plaque accumulation. Retention of bacterial plaque, represents a risk for white spot lesions and development of periodontal disease.

  5. Sleep confers a benefit for retention of statistical language learning in 6.5month old infants.

    Science.gov (United States)

    Simon, Katharine N S; Werchan, Denise; Goldstein, Michael R; Sweeney, Lucia; Bootzin, Richard R; Nadel, Lynn; GĂłmez, Rebecca L

    2017-04-01

    Infants show robust ability to track transitional probabilities within language and can use this information to extract words from continuous speech. The degree to which infants remember these words across a delay is unknown. Given well-established benefits of sleep on long-term memory retention in adults, we examine whether sleep similarly facilitates memory in 6.5month olds. Infants listened to an artificial language for 7minutes, followed by a period of sleep or wakefulness. After a time-matched delay for sleep and wakefulness dyads, we measured retention using the head-turn-preference procedure. Infants who slept retained memory for the extracted words that was prone to interference during the test. Infants who remained awake showed no retention. Within the nap group, retention correlated with three electrophysiological measures (1) absolute theta across the brain, (2) absolute alpha across the brain, and (3) greater fronto-central slow wave activity (SWA). Copyright © 2016 Elsevier Inc. All rights reserved.

  6. A national study of the retention of Irish opiate users in methadone substitution treatment

    LENUS (Irish Health Repository)

    Mullen, Louise

    2012-07-02

    Background: Retention in treatment is a key indicator of methadone treatment success. The study aims to identify factors that are associated with retention. Objectives: To determine retention in treatment at 12 months for Irish opiate users in methadone substitution treatment and to indicate factors that increase the likelihood of retention. Methods: National cohort study of randomly selected opiate users commencing methadone treatment in 1999, 2001, and 2003 (n = 1269). Results: Sixty-one percent of patients attending methadone treatment remained in continuous treatment for more than 1 year. Retention in treatment at 12 months was associated with age, gender, facility type, and methadone dose. Age and gender were no longer significant when adjusted for other variables in the model. Those who attended a specialist site were twice as likely to leave methadone treatment within 12 months compared with those who attended a primary care physician. The most important predictor of retention in treatment was methadone dose. Those who received <60 mg of methadone were three times more likely to leave treatment. Conclusion: Retention in methadone treatment is high in Ireland in a variety of settings. The main factors influencing retention in methadone treatment was an adequate methadone dose and access to a range of treatment settings including from primary care physicians. Scientific Significance: Providing an adequate dose of methadone during treatment will increase the likelihood of treatment retention. Methadone treatment by the primary care physician is a successful method of retaining opioid users in treatment.

  7. Building Store Satisfaction Centred on Customer Retention in Clothing Retailing: Store Design and Ease of Shopping

    Directory of Open Access Journals (Sweden)

    Gulden Turhan

    2016-01-01

    Full Text Available The study’s research model suggests that store design and ease of shopping are associated with customer retention through a mediated pathway in which store design and ease of shopping influence perceived store satisfaction, which in turn, influences customer retention. This survey was administered to two separate clothing stores offered to either females or males (in total, 533 participants. Using structural equation modelling methodology, data was analysed to explain the interrelations among the variables in the model. The results of an empirical study of a sample of store shoppers revealed that store design and ease of shopping influence customer retention in an indirect way through customer perception of satisfaction with the store. In building store satisfaction that is centred on customer retention, store design and shopping ease differ in their relative influences. This difference is high for females, but for men as low as to be considered negligible in males. As a result, improving customers’ perceptions of store design and ease of shopping is a way to ensure store satisfaction support customer retention. The results of the study provide a new insight into the relationships by suggesting indirect effects of shopping ease and store design on consumer retention by their impacts on store satisfaction, rather than direct effects.

  8. Building Store Satisfaction Centred on Customer Retention in Clothing Retailing: Store Design and Ease of Shopping

    Directory of Open Access Journals (Sweden)

    Gulden Turhan

    2014-01-01

    Full Text Available The study’s research model suggests that store design and ease of shopping are associated with customer retention through a mediated pathway in which store design and ease of shopping influence perceived store satisfaction, which in turn, influences customer retention. This survey was administered to two separate clothing stores offered to either females or males (in total, 533 participants. Using structural equation modelling methodology, data was analysed to explain the interrelations among the variables in the model. The results of an empirical study of a sample of store shoppers revealed that store design and ease of shopping influence customer retention in an indirect way through customer perception of satisfaction with the store. In building store satisfaction that is centred on customer retention, store design and shopping ease differ in their relative influences. This difference is high for females, but for men as low as to be considered negligible in males. As a result, improving customers’ perceptions of store design and ease of shopping is a way to ensure store satisfaction support customer retention. The results of the study provide a new insight into the relationships by suggesting indirect effects of shopping ease and store design on consumer retention by their impacts on store satisfaction, rather than direct effects.

  9. External and Internal Barriers to Studying Can Affect Student Success and Retention in a Diverse Classroom

    Directory of Open Access Journals (Sweden)

    Laurence Clement

    2016-12-01

    Full Text Available Although a majority of under-represented minority (URM students begin their postsecondary education at community colleges, little is known about barriers to success and retention for transfer-bound science students. This study focuses on some of the barriers that affect these students’ ability to study adequately for a community college “gateway” course. It tests whether instructors’ expectations of study time were realistic for community college students and whether students reported facing external barriers, such as job and family responsibilities, or internal barriers to studying, such as lack of motivational, cognitive, and metacognitive abilities, all of which have been shown to impact academic success and retention. It also tests whether students who faced such barriers were less likely to succeed in and complete the course, as well as whether time spent studying was related to course success. The findings reported here show that community college students do not have enough available time to study and that external and internal barriers are both prevalent among these students. In addition, students who faced such barriers are more likely to fail or drop the class. Results also show that study time is positively correlated with retention, but not performance, as well as with some motivational, cognitive, and metacognitive dimensions of self-regulated learning. These findings lead to new questions, including whether student success in a community college class is associated with the use of cognitive and metacognitive learning strategies for students with no prior degrees, and whether increased course structure may improve success for college students with lower self-regulated abilities.

  10. Superconducting solenoid model magnet test results

    International Nuclear Information System (INIS)

    Carcagno, R.; Dimarco, J.; Feher, S.; Ginsburg, C.M.; Hess, C.; Kashikhin, V.V.; Orris, D.F.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.A.; Terechkine, I.; Tompkins, J.C.; Wokas, T.; Fermilab

    2006-01-01

    Superconducting solenoid magnets suitable for the room temperature front end of the Fermilab High Intensity Neutrino Source (formerly known as Proton Driver), an 8 GeV superconducting H- linac, have been designed and fabricated at Fermilab, and tested in the Fermilab Magnet Test Facility. We report here results of studies on the first model magnets in this program, including the mechanical properties during fabrication and testing in liquid helium at 4.2 K, quench performance, and magnetic field measurements. We also describe new test facility systems and instrumentation that have been developed to accomplish these tests

  11. Superconducting solenoid model magnet test results

    Energy Technology Data Exchange (ETDEWEB)

    Carcagno, R.; Dimarco, J.; Feher, S.; Ginsburg, C.M.; Hess, C.; Kashikhin, V.V.; Orris, D.F.; Pischalnikov, Y.; Sylvester, C.; Tartaglia, M.A.; Terechkine, I.; /Fermilab

    2006-08-01

    Superconducting solenoid magnets suitable for the room temperature front end of the Fermilab High Intensity Neutrino Source (formerly known as Proton Driver), an 8 GeV superconducting H- linac, have been designed and fabricated at Fermilab, and tested in the Fermilab Magnet Test Facility. We report here results of studies on the first model magnets in this program, including the mechanical properties during fabrication and testing in liquid helium at 4.2 K, quench performance, and magnetic field measurements. We also describe new test facility systems and instrumentation that have been developed to accomplish these tests.

  12. Determinants of feedback retention in soccer players

    Directory of Open Access Journals (Sweden)

    JanuĂĄrio Nuno

    2016-06-01

    Full Text Available This study analyzed soccer players’ retention of coaches’ feedback during training sessions. We intended to determine if the retention of information was influenced by the athletes’ personal characteristic (age, gender and the sports level, the quantity of information included in coach’s feedback (the number of ideas and redundancy, athletes’ perception of the relevance of the feedback information and athletes’ motivation as well as the attention level. The study that was conducted over the course of 18 sessions of soccer practice, involved 12 coaches (8 males, 4 females and 342 athletes (246 males, 96 females, aged between 10 and 18 years old. All coach and athlete interventions were transposed to a written protocol and submitted to content analysis. Descriptive statistics and multiple linear regression were calculated. The results showed that a substantial part of the information was not retained by the athletes; in 65.5% of cases, athletes experienced difficulty in completely reproducing the ideas of the coaches and, on average, the value of feedback retention was 57.0%. Six variables with a statistically significant value were found: gender, the athletes’ sports level, redundancy, the number of transmitted ideas, athletes’ perception of the relevance of the feedback information and the athletes’ motivation level.

  13. Improved motor sequence retention by motionless listening.

    Science.gov (United States)

    Lahav, Amir; Katz, Tal; Chess, Roxanne; Saltzman, Elliot

    2013-05-01

    This study examined the effect of listening to a newly learned musical piece on subsequent motor retention of the piece. Thirty-six non-musicians were trained to play an unfamiliar melody on a piano keyboard. Next, they were randomly assigned to participate in three follow-up listening sessions over 1 week. Subjects who, during their listening sessions, listened to the same initial piece showed significant improvements in motor memory and retention of the piece despite the absence of physical practice. These improvements included increased pitch accuracy, time accuracy, and dynamic intensity of key pressing. Similar improvements, though to a lesser degree, were observed in subjects who, during their listening sessions, were distracted by another task. Control subjects, who after learning the piece had listened to nonmusical sounds, showed impaired motoric retention of the piece at 1 week from the initial acquisition day. These results imply that motor sequences can be established in motor memory without direct access to motor-related information. In addition, the study revealed that the listening-induced improvements did not generalize to the learning of a new musical piece composed of the same notes as the initial piece learned, limiting the effects to musical motor sequences that are already part of the individual's motor repertoire.

  14. Temperature dependence of deuterium retention mechanisms in tungsten

    Energy Technology Data Exchange (ETDEWEB)

    Roszell, J.P. [University of Toronto Institute for Aerospace Studies, 4925 Dufferin Street, Toronto, Ontario, M3H 5T6 (Canada); Davis, J.W., E-mail: jwdavis@starfire.utias.utoronto.ca [University of Toronto Institute for Aerospace Studies, 4925 Dufferin Street, Toronto, Ontario, M3H 5T6 (Canada); Haasz, A.A. [University of Toronto Institute for Aerospace Studies, 4925 Dufferin Street, Toronto, Ontario, M3H 5T6 (Canada)

    2012-10-15

    The retention of 500 eV D{sup +} was measured as a function of implantation temperature in single- (SCW) and poly-crystalline (PCW) tungsten. The results show a decrease in retention of {approx}2 orders of magnitude over the temperature range of 350-550 K in SCW and a decrease of an order of magnitude over the temperature range of 600-700 K in PCW. Inspection of the TDS spectra showed a shift in peak location from 600 to 800 K as temperature was increased above 350 K in SCW and above 450 K in PCW specimens. TMAP modeling showed that the change in peak location corresponds to a change in trapping energy from 1.3 eV for the 600 K peak to 2.1 eV for the 800 K peak. It is proposed that for implantations performed above 350 K in SCW and 450 K in PCW, deuterium-containing vacancies are able to diffuse and combine to create stable nano-bubbles within the crystal lattice. The formation of nano-bubbles due to the annihilation of deuterium-vacancy complexes results in a change in the trapping energy from 1.3 to 2.1 eV as well as a decrease in retention as some of the deuterium-vacancy complexes will be destroyed at surfaces or grain boundaries, decreasing the number of trapping sites available.

  15. Temperature dependence of deuterium retention mechanisms in tungsten

    International Nuclear Information System (INIS)

    Roszell, J.P.; Davis, J.W.; Haasz, A.A.

    2012-01-01

    The retention of 500 eV D + was measured as a function of implantation temperature in single- (SCW) and poly-crystalline (PCW) tungsten. The results show a decrease in retention of ∌2 orders of magnitude over the temperature range of 350–550 K in SCW and a decrease of an order of magnitude over the temperature range of 600–700 K in PCW. Inspection of the TDS spectra showed a shift in peak location from 600 to 800 K as temperature was increased above 350 K in SCW and above 450 K in PCW specimens. TMAP modeling showed that the change in peak location corresponds to a change in trapping energy from 1.3 eV for the 600 K peak to 2.1 eV for the 800 K peak. It is proposed that for implantations performed above 350 K in SCW and 450 K in PCW, deuterium-containing vacancies are able to diffuse and combine to create stable nano-bubbles within the crystal lattice. The formation of nano-bubbles due to the annihilation of deuterium-vacancy complexes results in a change in the trapping energy from 1.3 to 2.1 eV as well as a decrease in retention as some of the deuterium-vacancy complexes will be destroyed at surfaces or grain boundaries, decreasing the number of trapping sites available.

  16. Temperature dependence of deuterium retention mechanisms in tungsten

    Science.gov (United States)

    Roszell, J. P.; Davis, J. W.; Haasz, A. A.

    2012-10-01

    The retention of 500 eV D+ was measured as a function of implantation temperature in single- (SCW) and poly-crystalline (PCW) tungsten. The results show a decrease in retention of ˜2 orders of magnitude over the temperature range of 350-550 K in SCW and a decrease of an order of magnitude over the temperature range of 600-700 K in PCW. Inspection of the TDS spectra showed a shift in peak location from 600 to 800 K as temperature was increased above 350 K in SCW and above 450 K in PCW specimens. TMAP modeling showed that the change in peak location corresponds to a change in trapping energy from 1.3 eV for the 600 K peak to 2.1 eV for the 800 K peak. It is proposed that for implantations performed above 350 K in SCW and 450 K in PCW, deuterium-containing vacancies are able to diffuse and combine to create stable nano-bubbles within the crystal lattice. The formation of nano-bubbles due to the annihilation of deuterium-vacancy complexes results in a change in the trapping energy from 1.3 to 2.1 eV as well as a decrease in retention as some of the deuterium-vacancy complexes will be destroyed at surfaces or grain boundaries, decreasing the number of trapping sites available.

  17. Urinary retention associated with herpes zoster infection.

    Science.gov (United States)

    Cohen, L M; Fowler, J F; Owen, L G; Callen, J P

    1993-01-01

    Herpes zoster infection particularly involving the sacral dermatomes has been associated with bladder and bowel dysfunction, most commonly urinary retention. We report two patients who developed acute urinary retention, one of whom also had constipation, within days of herpes zoster skin lesions of the S2-S4 dermatomes. Herpes zoster is a reversible cause of neurogenic bladder and bowel dysfunction and should be considered in a patient that presents with acute urinary retention and/or constipation. Sensory abnormalities and flaccid detrusor paralysis are most likely involved in the pathogenesis.

  18. Improving Attendance and Retention in Out-of-School Time Programs. Research-to-Results Practitioner Insights. Publication # 2007-17

    Science.gov (United States)

    Kennedy, Elena; Wilson, Brooke; Valladares, Sherylls; Bronte-Tinkew, Jacinta

    2007-01-01

    Regular participation in out-of-school time activities is associated with benefits for children. However, children cannot reap the benefits of program participation if they do not attend programs in the first place. This brief focuses on ways in which out-of-school time programs can improve the attendance and retention of children and youth in


  19. Drug Retention Times

    Energy Technology Data Exchange (ETDEWEB)

    Center for Human Reliability Studies

    2007-05-01

    The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user.

  20. Mixed retention mechanism of proteins in weak anion-exchange chromatography.

    Science.gov (United States)

    Liu, Peng; Yang, Haiya; Geng, Xindu

    2009-10-30

    Using four commercial weak anion-exchange chromatography (WAX) columns and 11 kinds of different proteins, we experimentally examined the involvement of hydrophobic interaction chromatography (HIC) mechanism in protein retention on the WAX columns. The HIC mechanism was found to operate in all four WAX columns, and each of these columns had a better resolution in the HIC mode than in the corresponding WAX mode. Detailed analysis of the molecular interactions in a chromatographic system indicated that it is impossible to completely eliminate hydrophobic interactions from a WAX column. Based on these results, it may be possible to employ a single WAX column for protein separation by exploiting mixed modes (WAX and HIC) of retention. The stoichiometric displacement theory and two linear plots were used to show that mechanism of the mixed modes of retention in the system was a combination of two kinds of interactions, i.e., nonselective interactions in the HIC mode and selective interactions in the IEC mode. The obtained U-shaped elution curve of proteins could be distinguished into four different ranges of salt concentration, which also represent four retention regions.

  1. A biologically relevant method for considering patterns of oceanic retention in the Southern Ocean

    Science.gov (United States)

    Mori, Mao; Corney, Stuart P.; Melbourne-Thomas, Jessica; Klocker, Andreas; Sumner, Michael; Constable, Andrew

    2017-12-01

    Many marine species have planktonic forms - either during a larval stage or throughout their lifecycle - that move passively or are strongly influenced by ocean currents. Understanding these patterns of movement is important for informing marine ecosystem management and for understanding ecological processes generally. Retention of biological particles in a particular area due to ocean currents has received less attention than transport pathways, particularly for the Southern Ocean. We present a method for modelling retention time, based on the half-life for particles in a particular region, that is relevant for biological processes. This method uses geostrophic velocities at the ocean surface, derived from 23 years of satellite altimetry data (1993-2016), to simulate the advection of passive particles during the Southern Hemisphere summer season (from December to March). We assess spatial patterns in the retention time of passive particles and evaluate the processes affecting these patterns for the Indian sector of the Southern Ocean. Our results indicate that the distribution of retention time is related to bathymetric features and the resulting ocean dynamics. Our analysis also reveals a moderate level of consistency between spatial patterns of retention time and observations of Antarctic krill (Euphausia superba) distribution.

  2. Effects of glibenclamide on memory retention of passive avoidance learning in rats

    Directory of Open Access Journals (Sweden)

    MH. Esmaeili

    2017-08-01

    Full Text Available Background: Glucose increases memory in rats, and inhibit memory impairments produced by morphine. One mechanism by which glucose might act on memory via regulating the ATP-sensitive potassium channel. Objective: The aim of present study was to investigate the effects of glibenclamide on memory retention of passive avoidance learning in rats. Methods: This experimental study has been conducted in Qazvin University of Medical Sciences (2016. Forty male Wistar rats were divided into: Control, DMSO and glibenclamide groups (n=8. All rats were trained in a passive avoidance task (50 Hz, 1 mA, 3 s. DMSO (0.2 ml or glibenclamide (1, 2, 5 mg/kg, i.p. were injected for 10 days before training. Retention test was done 48 h later. Memory retention of each animal was measured as latency takes to enter the dark chamber. Findings: The time spent in the light chamber area before entering to the dark area and total time spent in the light chamber in the glibenclamide groups were less than control group. These times in the glibenclamide (5 mg/kg group was significantly lower than control group (P<0.05, conversely total time spent in the dark chamber in the glibenclamide groups were higher than control group. Conclusion: Glibenclamide, as an ATP-sensitive potassium channel blocker, may reduce memory retention by increasing insulin levels and, consequently, reducing blood glucose levels.

  3. The Picmonic(Âź) Learning System: enhancing memory retention of medical sciences, using an audiovisual mnemonic Web-based learning platform.

    Science.gov (United States)

    Yang, Adeel; Goel, Hersh; Bryan, Matthew; Robertson, Ron; Lim, Jane; Islam, Shehran; Speicher, Mark R

    2014-01-01

    Medical students are required to retain vast amounts of medical knowledge on the path to becoming physicians. To address this challenge, multimedia Web-based learning resources have been developed to supplement traditional text-based materials. The Picmonic(Âź) Learning System (PLS; Picmonic, Phoenix, AZ, USA) is a novel multimedia Web-based learning platform that delivers audiovisual mnemonics designed to improve memory retention of medical sciences. A single-center, randomized, subject-blinded, controlled study was conducted to compare the PLS with traditional text-based material for retention of medical science topics. Subjects were randomly assigned to use two different types of study materials covering several diseases. Subjects randomly assigned to the PLS group were given audiovisual mnemonics along with text-based materials, whereas subjects in the control group were given the same text-based materials with key terms highlighted. The primary endpoints were the differences in performance on immediate, 1 week, and 1 month delayed free-recall and paired-matching tests. The secondary endpoints were the difference in performance on a 1 week delayed multiple-choice test and self-reported satisfaction with the study materials. Differences were calculated using unpaired two-tailed t-tests. PLS group subjects demonstrated improvements of 65%, 161%, and 208% compared with control group subjects on free-recall tests conducted immediately, 1 week, and 1 month after study of materials, respectively. The results of performance on paired-matching tests showed an improvement of up to 331% for PLS group subjects. PLS group subjects also performed 55% greater than control group subjects on a 1 week delayed multiple choice test requiring higher-order thinking. The differences in test performance between the PLS group subjects and the control group subjects were statistically significant (P<0.001), and the PLS group subjects reported higher overall satisfaction with the

  4. Verbal memory improved by D-amphetamine: influence of the testing effect.

    Science.gov (United States)

    Zeeuws, Inge; Deroost, Natacha; Soetens, Eric

    2010-07-01

    The improvement of long-term retention of verbal memory after an acute administration of D-amphetamine in recall and recognition tasks has been ascribed to an influence of the drug on memory consolidation. Because recent research has demonstrated that intermediate testing is of overriding importance for retention, we investigated whether D-amphetamine modulates the repeated testing effect in verbal long-term recognition. Forty men participated in two double blind placebo controlled studies. In Experiment 1, we manipulated the number of recognition tests and in Experiment 2, we compared repeated with nonrepeated testing of the same items. Drug effects were observed on delayed tests only, leaving immediate recognition unaffected. Number of intermediate recognition tests and repeated testing of the same items were not affected by D-amphetamine. We conclude that the D-amphetamine memory enhancement is not related to the testing effect. This result supports that D-amphetamine modulates other aspects of the consolidation process, probably related to context effects. (c) 2010 John Wiley & Sons, Ltd.

  5. Testing Memories of Personally Experienced Events: The Testing Effect Seems Not to Persist in Autobiographical Memory

    Science.gov (United States)

    Emmerdinger, Kathrin J.; Kuhbandner, Christof

    2018-01-01

    Numerous studies have shown that retrieving contents from memory in a test improves long-term retention for those contents, even when compared to restudying (i.e., the “testing effect”). The beneficial effect of retrieval practice has been demonstrated for many different types of memory representations; however, one particularly important memory system has not been addressed in previous testing effect research: autobiographical memory. The aim of the present study was to examine the effect of retrieving memories for personally experienced events on long-term memory for those events. In an initial elicitation session, participants described memories for personally experienced events in response to a variety of cue words. In a retrieval practice/restudy session the following day, they repeatedly practiced retrieval for half of their memories by recalling and writing down the previously described events; the other half of memories was restudied by rereading and copying the event descriptions. Long-term retention of all previously collected memories was assessed at two different retention intervals (2 weeks and 13 weeks). In the retrieval practice session, a hypermnesic effect emerged, with memory performance increasing across the practice cycles. Long-term memory performance significantly dropped from the 2-weeks to the 13-weeks retention interval, but no significant difference in memory performance was observed between previously repeatedly retrieved and previously repeatedly restudied memories. Thus, in autobiographical memory, retrieval practice seems to be no more beneficial for long-term retention than repeated re-exposure. PMID:29881365

  6. Timing of quizzes during learning: Effects on motivation and retention.

    Science.gov (United States)

    Healy, Alice F; Jones, Matt; Lalchandani, Lakshmi A; Tack, Lindsay Anderson

    2017-06-01

    This article investigates how the timing of quizzes given during learning impacts retention of studied material. We investigated the hypothesis that interspersing quizzes among study blocks increases student engagement, thus improving learning. Participants learned 8 artificial facts about each of 8 plant categories, with the categories blocked during learning. Quizzes about 4 of the 8 facts from each category occurred either immediately after studying the facts for that category (standard) or after studying the facts from all 8 categories (postponed). In Experiment 1, participants were given tests shortly after learning and several days later, including both the initially quizzed and unquizzed facts. Test performance was better in the standard than in the postponed condition, especially for categories learned later in the sequence. This result held even for the facts not quizzed during learning, suggesting that the advantage cannot be due to any direct testing effects. Instead the results support the hypothesis that interrupting learning with quiz questions is beneficial because it can enhance learner engagement. Experiment 2 provided further support for this hypothesis, based on participants' retrospective ratings of their task engagement during the learning phase. These findings have practical implications for when to introduce quizzes in the classroom. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  7. A dynamic processes study of PM retention by trees under different wind conditions.

    Science.gov (United States)

    Xie, Changkun; Kan, Liyan; Guo, Jiankang; Jin, Sijia; Li, Zhigang; Chen, Dan; Li, Xin; Che, Shengquan

    2018-02-01

    Particulate matter (PM) is one of the most serious environmental problems, exacerbating respiratory and vascular illnesses. Plants have the ability to reduce non-point source PM pollution through retention on leaves and branches. Studies of the dynamic processes of PM retention by plants and the mechanisms influencing this process will help to improve the efficiency of urban greening for PM reduction. We examined dynamic processes of PM retention and the major factors influencing PM retention by six trees with different branch structure characteristics in wind tunnel experiments at three different wind speeds. The results showed that the changes of PM numbers retained by plant leaves over time were complex dynamic processes for which maximum values could exceed minimum values by over 10 times. The average value of PM measured in multiple periods and situations can be considered a reliable indicator of the ability of the plant to retain PM. The dynamic processes were similar for PM 10 and PM 2.5 . They could be clustered into three groups simulated by continually-rising, inverse U-shaped, and U-shaped polynomial functions, respectively. The processes were the synthetic effect of characteristics such as species, wind speed, period of exposure and their interactions. Continually-rising functions always explained PM retention in species with extremely complex branch structure. Inverse U-shaped processes explained PM retention in species with relatively simple branch structure and gentle wind. The U-shaped processes mainly explained PM retention at high wind speeds and in species with a relatively simple crown. These results indicate that using plants with complex crowns in urban greening and decreasing wind speed in plant communities increases the chance of continually-rising or inverse U-shaped relationships, which have a positive effect in reducing PM pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. In Vitro Retentive Effect of Groove, Sandblasting, and Cement Type on Stainless Steel Crowns in Primary Molars.

    Science.gov (United States)

    Pathak, Sidhant; Shashibhushan, K K; Bharath, K P; Poornima, P; Reddy, V V Subba

    2015-01-01

    The purpose of this study was to evaluate and compare the effect of placing vertical grooves, sandblasting, and luting cements on the retention of stainless steel crowns (SSCs). Eighty extracted primary molars were mounted in acrylic blocks. Specimens were divided into Group 1 (RelyX U200) and Group 2 (Smart Cem2). Teeth in each group were further subdivided into Subgroup A (no vertical grooves and no sandblasting), Subgroup B (vertical grooves), Subgroup C (sandblasting of crowns), and Subgroup D (vertical grooves and sandblasting of crowns). After cementation, SSCs were pulled off using a universal testing machine. One-way analysis of variance was used for statistical analyses. In Groups 1 and 2, the highest retentive strengths were found in Subgroup D (1,124 and 783 kPa, respectively), followed by Subgroup C (1,066 and 748 kPa, respectively), Subgroup A (762 and 356 kPa, respectively), and Subgroup B (743 and 314 kPa, respectively). Retentive strength in Group one was significantly higher than in Group two; Subgroups A and B were significantly lower than C and D. RelyX U200 showed higher retentive strength than Smart Cem2. Sandblasting increased the retention strength, whereas a vertical groove had no significant effect on retention.

  9. Legal provisions governing the acknowledgment of test results

    International Nuclear Information System (INIS)

    Strecker, A.

    1982-01-01

    The legal provisions governing the acknowledgment of test results are most frequently applied by administrative orders (design and qualification approvals or specimen testing and approval) and are thus claimable and voidable in accordance with general administrative law. The acknowledgment of test certificates requires a legal basis. Test results, however, can be acknowledged also by administrative bodies. Recently, the Federal Government began to delegate more of its legal authority in this field to private institutions, allowing test results to be acknowledged and test certificates to be issued by government controlled private institutions. (orig.) [de

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

    Science.gov (United States)

    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. Xe-133 accumulation in fatty liver: hepatic uptake and washout correlated with pulmonary and mesenteric retention

    International Nuclear Information System (INIS)

    Samuels, L.D.

    1980-01-01

    Xe-133 uptake in patients with fatty livers is described and compared with uptake and retention in lungs, blood and mesenteric fat and with normal hepatic uptake. In the absence of obstructive lung disease or excessive obesity, Xe-133 uptake and retention is a valuable means of screening patients for the presence of fatty liver. Although non-specific for the etiology of fatty liver, the test is an effective and non-invasive method of detection which merits further application. (author)

  12. Herpes zoster-induced acute urinary retention.

    Science.gov (United States)

    Addison, Ben; Harvey, Martyn

    2013-06-01

    Urinary retention is a common acute presentation for men in their later decades. Potential contributing pathologies are numerous. We report an unusual case of acute urinary retention requiring catheterisation secondary to sacral herpes zoster reactivation (S2-4) in an 88-year-old man with minimal preceding obstructive symptoms. © 2013 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

  13. Krypton retention on solid adsorbents

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.

    1981-08-01

    Over a dozen prospective adsorbents for krypton were studied and evaluated with respect to adsorption capacity and cost for dissolver off-gas streams from nuclear reprocessing plants. Results show that, at subambient temperature (-40 0 to -80 0 C), the commercially available hydrogen mordenite has sufficient adsorptive capacity to be the most cost-effective material studied. Silver mordenite has a higher capacity for krypton retention, but is 50 times more expensive than hydrogen mordenite. The results indicate that a solid adsorbent system is feasible and competitive with other developing systems whih utilize fluorocarbon absorption and cryogenic distillation

  14. A new skeletal retention system for retaining anterior open bites

    Directory of Open Access Journals (Sweden)

    Bodore Albaker

    2013-01-01

    Full Text Available Objectives: Relapse of anterior open bite after treatment poses a challenge to orthodontists and warrants finding new methods. We aimed to compare the effect of a skeletal retention (SR system to the conventional retention (CR commonly used. Materials and Methods: Twenty patients participated in this study. SR group ten patients (five females and five males with mean age of 16.2 years, CR group ten patients (five females and five males with mean age of 17.1 years in pretreatment stage. The SR system is comprised of four self-drilling miniscrews and vacuum retainers with interarch elastics where the CR group is comprised of removable or fixed retainers. Pretreatment (T1, posttreatment (T2, and 1-year follow up (T3 lateral cephalograms were taken and analyzed to compare the stability of both retention modalities. Results: The overbite in the CR group showed more relapse in the form of significant reduction when compared to the SR group (P < 0.001. The overbite was reduced only by 0.1 mm (±0.3 in the SR group compared to 1.4 mm (±0.9 in the CR group. In the CR group, the upper incisors and first molar showed a more significant relapse compared to the SR group (P < 0.05. Conclusion: Skeletal retention using miniscrews and vertical elastic is an effective method for retention of anterior open bite cases.

  15. Learning From Tests: Facilitation of Delayed Recall by Initial Recognition Alternatives.

    Science.gov (United States)

    Whitten, William B., II; Leonard, Janet Mauriello

    1980-01-01

    Two experiments were designed to determine the effects of multiple-choice recognition test alternatives on subsequent memory for the correct answers. Results of both experiments are interpreted as demonstrations of the principle that long-term retention is facilitated such that memory evaluation occurs during initial recognition tests. (Author/RD)

  16. Retention factors in relation to organisational commitment in medical and information technology services

    Directory of Open Access Journals (Sweden)

    Jeannette van Dyk

    2012-02-01

    Full Text Available Orientation: Retaining staff with scarce and critical skills in the medical and information technology (IT industry has become a top priority because of skills shortages.Research purpose: The objectives of the study were to investigate empirically: (1 the relationship between employees’ satisfaction with organisational retention factors (measured by the Retention Factors Scale and their organisational commitment (measured by the Organisational Commitment Questionnaire and (2 whether gender, age, race and tenure groups differ significantly in terms of these variables.Motivation for the study: Medical and information technology professionals have specialised and hard to replace skills. They also have strong tendencies to leave their organisations and countries. Understanding the retention factors that will increase their organisational commitment may benefit the organisations who want to retain their valuable talent.Research design, approach and method: The researchers used a cross-sectional survey design to collect data from a purposive sample of 206 staff members who had scarce skills in a South African medical and information technology services company. Correlational and inferential statistics were computed to achieve the objectives.Main findings: The results showed that the participants’ satisfaction with retention factors has a significant relationship with their organisational commitment and that the biographical groups differ significantly in terms of the variables.Practical/managerial implications: The measured retention factors were all associated with human resource management practices that influence employees’ intentions to leave.Contribution/value-add: The results are important to managers who are interested in retaining staff who have scarce skills and provide valuable pointers for designing effective retention strategies.

  17. In vessel retention for VVER 1000 - Experimental work

    International Nuclear Information System (INIS)

    Batek, D.

    2015-01-01

    After Fukushima accident, the nuclear community realized that it is necessary to have strategy and solution for severe accident management. In Vessel Retention (IVR) of corium is an important strategy to mitigate the consequences of a severe accident. In this poster the author reviews the present status of experimental works made by UJV (Czech Republic) from 2012 until now, on the IVR strategy specifically applied for the VVER 1000 unit. The BESTH 1 experiment was prepared to test the behavior of the RPV (Reactor Pressure Vessel) surface under 2 configurations: clean and corroded. BESTH 2 experiment is a modification of BESTH 1 experiment in order to get greater thermal fluxes. The BESTH 3 facility is a large scale experiment that is under extensive design (2016-2017) whose main objective will be to investigate the results of vast analytical works made by experts with specialization of severe accident phenomenology

  18. Magnetite effect in radionuclide retention : cesium, strontium, molybdenum and selenium

    International Nuclear Information System (INIS)

    Rovira, M.; Casas, I.; Gimenez, J.; Clarens, F.; Pablo, J. de

    2004-01-01

    In this work we have investigated the interaction of magnetite with cesium, strontium, molybdenum and selenium, in the frame of radionuclide retention by canister corrosion products. For each radionuclide, the retention on magnetite has been studied as a function of pH and the mass/ volume ratio. The experimental results have been modeled by means of Surface Complexation Models (SCM), that constitute a tool that allows an approach to sorption mechanisms in a wide range of experimental conditions taking into account electrostatic interactions at the mineral-water interface.(Author)

  19. Average Soil Water Retention Curves Measured by Neutron Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Chu-Lin [ORNL; Perfect, Edmund [University of Tennessee, Knoxville (UTK); Kang, Misun [ORNL; Voisin, Sophie [ORNL; Bilheux, Hassina Z [ORNL; Horita, Juske [Texas Tech University (TTU); Hussey, Dan [NIST Center for Neutron Research (NCRN), Gaithersburg, MD

    2011-01-01

    Water retention curves are essential for understanding the hydrologic behavior of partially-saturated porous media and modeling flow transport processes within the vadose zone. In this paper we report direct measurements of the main drying and wetting branches of the average water retention function obtained using 2-dimensional neutron radiography. Flint sand columns were saturated with water and then drained under quasi-equilibrium conditions using a hanging water column setup. Digital images (2048 x 2048 pixels) of the transmitted flux of neutrons were acquired at each imposed matric potential (~10-15 matric potential values per experiment) at the NCNR BT-2 neutron imaging beam line. Volumetric water contents were calculated on a pixel by pixel basis using Beer-Lambert s law after taking into account beam hardening and geometric corrections. To remove scattering effects at high water contents the volumetric water contents were normalized (to give relative saturations) by dividing the drying and wetting sequences of images by the images obtained at saturation and satiation, respectively. The resulting pixel values were then averaged and combined with information on the imposed basal matric potentials to give average water retention curves. The average relative saturations obtained by neutron radiography showed an approximate one-to-one relationship with the average values measured volumetrically using the hanging water column setup. There were no significant differences (at p < 0.05) between the parameters of the van Genuchten equation fitted to the average neutron radiography data and those estimated from replicated hanging water column data. Our results indicate that neutron imaging is a very effective tool for quantifying the average water retention curve.

  20. Impact limiter retention using a tape joint

    International Nuclear Information System (INIS)

    Gonzales, A.; Eakes, R.G.

    1986-01-01

    The Beneficial Uses Shipping System (BUSS) Cask employs polyurethane foam impact limiters that fit onto the ends of the cask. A foam impact limiter takes energy out of a system during a hypothetical accident condition by allowing foam crush and large deformations to occur. This, in turn, precludes high stresses or deformations from occurring to the cask. Because of the need to transmit significant amounts of heat to the environment, the BUSS cask impact limiters were designed to shield a minimum amount of the cask surface area. With this design impact limiter retention after the initial impact resulting from the 9 meter regulatory drops becomes a concern. Retention is essential to ensure the cask does not experience higher stresses during any secondary or rebound effects without impact limiters than it does during the 9 meter regulatory drop with impact limiters in place