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  1. The relationship between managerial leadership behaviors and staff nurse retention.

    PubMed

    Kleinman, Carol

    2004-01-01

    The purposes of this study were to describe perceptions of managerial leadership behaviors associated with staff nurse turnover and to compare nurse manager leadership behaviors as perceived by managers and their staff nurses. Effective leadership styles among nurse managers have been associated with staff nurse job satisfaction and retention. Although both transformational and transactional leadership styles have been described as effective, it is unclear which nurse manager leadership behaviors contribute most to staff nurse retention. This descriptive, correlational study was conducted at a 465-bed community hospital in the northeastern United States. All staff nurses and nurse managers employed in both ambulatory and acute care nursing units were invited to participate in the study. The study sample comprised 79 staff nurses and 10 nurse managers, who completed demographic forms and the 45-item Multifactor Leadership Questionnaire, which measures 12 dimensions of leadership style. Data were collected from July through September 2003. Active management by exception as perceived by staff nurses was the only managerial leadership style associated with staff nurse turnover (r = .26, p = .03). Compared with the perceptions among their staff nurses, nurse managers consistently perceived that they demonstrated a higher mean frequency of transformational leadership behaviors. The transactional leadership style of active management by exception not only appeared to be a deterrent to staff nurse retention but also reflected leadership perceptions among staff nurses who work evening and night shifts. This study also provides further evidence regarding a trend in which nurse managers and staff nurses do not concur on the frequency of transformational leadership behaviors but do demonstrate agreement on the frequency of transactional leadership behaviors. PMID:15898399

  2. On the inherent data fitting problems encountered in modeling retention behavior of analytes with dual retention mechanism.

    PubMed

    Tyteca, Eva; Desmet, Gert

    2015-07-17

    Some valuable insights have been obtained in the inherent fitting problems when trying to predict the retention time of complex, multi-modal retention modes such as encountered in HILIC and SFC. In this study, we used mathematical models with known input parameters to generate different sets of numerical test curves representative for systems exhibiting a complex, non-LSS dual retention behavior. Subsequently, we tried to fit these data sets using some popular (non-linear) literature models. Even in cases where a physical fitting model exists (e.g., the mixed model in case of pure additive adsorptive and partitioning retention), the fitting quality can only be expected to be relatively good (prediction errors expressed in terms of a normalized resolution error ɛRs) when carefully selecting the scouting runs and the appropriate starting values for the fitting algorithm. The latter can best be done using a comprehensive grid search scanning a wide range of different starting values. This becomes even more important when no good physical model is available and one has to use a non-physical fitting model, such as the empirical Neue-model. The use of higher-order models is found to be quasi indispensable to keep the prediction errors on the order of some ΔRs=0.05. Also, the choice of the scouting runs becomes even more important using these higher-order models. For highly retained compounds we recommend using scouting runs with long tG/t0-values or to include a run with a higher fraction of eluting solvent at the start of the gradient. When trying to predict gradient retention, errors with which the isocratic retention behavior is fitted are much less important for high retention factors k than errors made in the range of k near the one at the point of elution. The results obtained with a so-called segmented Neue-model (containing 7 parameters) were less good and thus practically not interesting (because of the high number of initial runs). PMID:26044381

  3. Mothers and Fathers Perform More Mate Retention Behaviors than Individuals without Children.

    PubMed

    Barbaro, Nicole; Shackelford, Todd K; Weekes-Shackelford, Viviana A

    2016-09-01

    Human life history is unique among primates, most notably the extraordinary length of infant dependency and the formation of long-term pair-bonds. Men and women are motivated to remain pair-bonded to maintain the distribution of male-provisioned resources to a woman and her offspring, or to protect offspring from infanticide. Men and women can employ several strategies to retain their mate and prevent their partner from defecting from the relationship, including individual mate retention (behaviors performed alone) and coalitional mate retention (behaviors performed by a close ally). The current research investigates whether men and women with children perform more frequent mate retention behaviors than men and women without children. Participants (n = 1003) currently in a heterosexual romantic relationship completed a survey, reporting whether they had genetic children with their current romantic partner and how frequently they performed various mate retention behaviors. The results indicate that men (n = 262) and women (n = 234) who share genetic children with their current partner performed more frequent individual mate retention behaviors and requested more frequent coalitional mate retention behaviors than men (n = 280) and women (n = 227) who do not share genetic children with their current partner. The results are interpreted as they relate to hypotheses concerning the evolution of pair-bonding in humans, and mate retention behaviors more generally. Limitations of the current research are discussed, and profitable avenues for future research in this domain are suggested. PMID:27147537

  4. Relationship between Leadership Behaviors of High School Principals and Teacher Retention in Texas

    ERIC Educational Resources Information Center

    Aiken, Debra L.

    2010-01-01

    The study investigated the relationship between leadership behaviors of high school principals and teacher retention in Texas. A total of 88 Texas high school principals participated in the survey. Leadership behaviors were measured using the Culturally Adapted Leadership for Inspired Business Excellence and Results (CALIBER) Leadership Assessment…

  5. Hormonal contraceptive use and mate retention behavior in women and their male partners.

    PubMed

    Welling, Lisa L M; Puts, David A; Roberts, S Craig; Little, Anthony C; Burriss, Robert P

    2012-01-01

    Female hormonal contraceptive use has been associated with a variety of physical and psychological side effects. Women who use hormonal contraceptives report more intense affective responses to partner infidelity and greater overall sexual jealousy than women not using hormonal contraceptives. Recently, researchers have found that using hormonal contraceptives with higher levels of synthetic estradiol, but not progestin, is associated with significantly higher levels of self-reported jealousy in women. Here, we extend these findings by examining the relationship between mate retention behavior in heterosexual women and their male partners and women's use of hormonal contraceptives. We find that women using hormonal contraceptives report more frequent use of mate retention tactics, specifically behaviors directed toward their partners (i.e., intersexual manipulations). Men partnered with women using hormonal contraceptives also report more frequent mate retention behavior, although this relationship may be confounded by relationship satisfaction. Additionally, among women using hormonal contraceptives, the dose of synthetic estradiol, but not of synthetic progesterone, positively predicts mate retention behavior frequency. These findings demonstrate how hormonal contraceptive use may influence behavior that directly affects the quality of romantic relationships as perceived by both female and male partners. PMID:22119340

  6. Retention behavior in tungsten and molybdenum exposed to high fluences of deuterium ions in TPE

    SciTech Connect

    J.P. Sharpe; R.D. Kolasinski; M. Shimada; P. Calderoni; R.A. Causey

    2009-06-01

    The Tritium Plasma Experiment (TPE) has been used to investigate deuterium fuel retention behavior in tungsten and molybdenum– materials utilized for plasma-facing surfaces in some existing tokamak plasma devices and under consideration for future devices. Although several studies have been performed over the past several years on these metals, many issues remain unresolved, including for example blister formation mechanisms and correlation to surface conditions. In this study we expose several metal samples to deuterium ion fluences up to 1026 ions/m2 and measure retention behavior with thermal desportion spectroscopy. Fractional retention of up to 2.0×10-5 is found for W at 600 K, and Mo similarly retains deuterium at a fraction of 1.5×10-5 at 600 K. Blistering was found for W samples exposed at temperatures above 453 K, whereas blistering was not observed for Mo samples at any experiment temperature.

  7. Multiple Family Groups for Child Behavior Difficulties: Retention Among Child Welfare-Involved Caregivers

    ERIC Educational Resources Information Center

    Gopalan, Geetha; Fuss, Ashley; Wisdom, Jennifer P.

    2015-01-01

    Purpose: The Multiple Family Group (MFG) service delivery model to reduce childhood disruptive behavior disorders has shown promise in engaging child welfare-involved families. This qualitative study examines caregivers' perceptions of factors that influence retention in MFGs among child welfare-involved families. Methods: Twenty-five…

  8. Multiple Family Groups for Child Behavior Difficulties Retention Among Child Welfare–Involved Caregivers

    PubMed Central

    Gopalan, Geetha; Fuss, Ashley; Wisdom, Jennifer P.

    2013-01-01

    Among children who remain at home with their permanent caregivers following a child welfare investigation, few who manifest emotional and behavioral difficulties actually engage in mental health treatment. The Multiple Family Group service delivery model to reduce childhood disruptive behavior disorders (MFG) has shown promise in engaging child welfare-involved families. This qualitative study examines caregiver perceptions of factors that influence retention in MFGs among child welfare-involved families. Methods Twenty-five predominantly Black and Hispanic adult (ages 26–57) female caregivers with child welfare services involvement participated in individual, in-depth interviews about their experience with MFGs. Transcribed interview data were thematically coded guided by grounded theory methodology. Emergent themes were subsequently organized into a conceptual framework. Results Within the overarching influence of child welfare services involvement, specific components of MFGs influencing retention included the quality of interaction among group members, group facilitators’ attentive approach with caregivers, supports designed to overcome logistical barriers (i.e., child care, transportation expenses, meals), and perceptions of MFG content and activities as fun and helpful. Caregiver factors, including their mental health and personal characteristics, as well as children’s behavior, (i.e., observed changes in behavioral difficulties) were also associated with retention. Conclusions High acceptability suggest utility for implementing MFGs within settings serving child welfare involved families, with additional modifications to tailor to setting and client features. PMID:26527856

  9. The Retention Effects of an Adult's Emotional Displays on Infant Behavior

    ERIC Educational Resources Information Center

    Hertenstein, Matthew J.; Campos, Joseph J.

    2004-01-01

    The goal of this investigation was to study the regulatory retention effects of an adult's emotional displays on infant behavior. In Study 1, 11- and 14-month-old infants were tested in a social-referencing-like paradigm in which a 1-hr delay was imposed between the exposure trials and the test trial. In Study 2, 11-month-olds were tested in the…

  10. The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng.

    PubMed

    Hu, Ping; Luo, Guo-An; Wang, Qing; Zhao, Zhong-Zhen; Wang, Wan; Jiang, Zhi-Hong

    2008-10-01

    This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. PMID:18958416

  11. The retention behavior of ginsenosides in HPLC and its application to quality assessment of Radix Ginseng.

    PubMed

    Hu, Ping; Luo, Guo-An; Wang, Qing; Zhao, Zhong-Zhen; Wang, Wan; Jiang, Zhi-Hong

    2009-05-01

    This study systematically investigated the retention behavior of seven neutral ginsenosides Rg(1), Re, Rf, Rb(1), Rb(2), Rc, Rd, and an acidic ginsenoside R(0), the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides' retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng. PMID:19471880

  12. Gas retention and release behavior in Hanford double-shell waste tanks

    SciTech Connect

    Meyer, P.A.; Brewster, M.E.; Bryan, S.A.

    1997-05-01

    This report describes the current understanding of flammable gas retention and release in Hanford double-shell waste tanks AN-103, AN-104, AN-105, AW-101, SY-101, and SY-103. This knowledge is based on analyses, experimental results, and observations of tank behavior. The applicable data available from the void fraction instrument, retained gas sampler, ball rheometer, tank characterization, and field monitoring are summarized. Retained gas volumes and void fractions are updated with these new data. Using the retained gas compositions from the retained gas sampler, peak dome pressures during a gas burn are calculated as a function of the fraction of retained gas hypothetically released instantaneously into the tank head space. Models and criteria are given for gas generation, initiation of buoyant displacement, and resulting gas release; and predictions are compared with observed tank behavior.

  13. Improving utilization of and retention in PMTCT services: Can behavioral economics help?

    PubMed Central

    2013-01-01

    Background The most recent strategic call to action of the World Health Organization sets the elimination of pediatric HIV as a goal. While recent efforts have focused on building infrastructure and ensuring access to high-quality treatment, we must now turn our focus to the behavior change needed to eliminate vertical transmission. We make the case for the application of concepts from the field of behavioral economics to prevention of mother-to-child transmission (PMTCT) programs to more effectively address demand-side issues of uptake and retention. Discussion We introduce five concepts from the field of behavioral economics and discuss their application to PMTCT programs: 1) Mentor mothers who come from similar circumstances as PMTCT patients can serve as social references who provide temporally salient modeling of utilization of services and adherence to treatment. 2) Economic incentives, like cell phone minutes or food vouchers, that reward adherence to PMTCT protocols leverage present bias, the observation that people are generally biased toward immediate versus future awards. 3) Default bias, our preference for the default option, is already being used in many countries in the form of opt-out testing, and could be expanded to all PMTCT programs. 4) We are hardwired to avoid loss more than to pursue an equivalent gain. PMTCT programs can take advantage of loss aversion through the use of commitment contracts that incentivize mothers to return to the clinic in order to avoid both reputational and financial loss. Summary Eliminating vertical transmission of HIV is an ambitious goal. To close the remaining gap, innovations are needed to address demand for PMTCT services. Behavioral economics offers a set of tools that can be engineered into PMTCT programs to increase uptake and improve retention with minimal investment. PMID:24112440

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

    PubMed

    Nierlich, Judith; Papageorgiou, Spyridon N; Bourauel, Christoph; Hültenschmidt, 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 < 0.001). The potentiodynamic analysis showed values from -82.5 to 102.8 mV for the open-circuit potential and from 566.7 to 1367.5 mV for the breakdown potential. Both the open-circuit and the breakdown potential varied considerably among these 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. PMID:27061513

  15. The effect of A teacher questioning strategy training program on teaching behavior, student achievement, and retention

    NASA Astrophysics Data System (ADS)

    Otto, Paul B.; Schuck, Robert F.

    The use of questions in the classroom has been employed throughout the recorded history of teaching. One still hears the term Socratic method during discussions of questioning procedures. The use of teacher questions is presently viewed as a viable procedure for effective instruction. This study was conducted to investigate the feasibility of training teachers in the use of a questioning technique and the resultant effect upon student learning. The Post-Test Only Control Group Design was used in randomly assigning teachers and students to experimental and control groups. A group of teachers was trained in the use of a specific questioning technique. Follow-up periodic observations were made of questioning technique behavior while teaching science units to groups of students. Post-unit achievement tests were administered to the student groups to obtain evidence of a relationship between the implementation of specific types of teacher questions and student achievement and retention. Analysis of observation data indicated a higher use of managerial and rhetorical questions by the control group than the experimental group. The experimental group employed a greater number of recall and data gathering questions as well as higher order data processing and data verification type questions. The student posttest achievement scores for both units of instruction were greater for the experimental groups than for the control groups. The retention scores for both units were Beater for the experimental groups than for the control groups.

  16. Retention behavior of alkylated polycyclic aromatic sulfur heterocycles on immobilized ionic liquid stationary phases.

    PubMed

    Antle, Patrick; Zeigler, Christian; Robbat, Albert

    2014-09-26

    Polycyclic aromatic sulfur heterocycles (PASH) are prevalent components of fossil fuel-based pollutants, and their accurate analysis is of critical importance in risk assessment and hazardous waste site remediation. PASH, however, have a wide range of volatilities and polarities and, as such, often coelute with one another and other sample components on the non-polar gas chromatography (GC) columns commonly used in their analysis. Immobilized ionic liquid (IL)-based stationary phases have been shown to provide better separation of polar compounds than non-polar columns, while withstanding higher temperatures than typical polar columns. In this way, they offer the opportunity of improved performance in the analysis of PASH in complex environmental samples and as the "more polar" column in GC×GC/MS analyses. In this study, the retention behavior of 119 PASH on four commercially-available IL stationary phases is reported and compared to behavior on three polydimethylsiloxane-based columns of varying polarities (DB-5, DB-17, and DB-200). Additionally, the utility of IL columns in GC×GC analyses of PASH-containing coal tar samples is examined. PMID:25155062

  17. Prediction of salt effects on protein phase behavior by HIC retention and thermal stability.

    PubMed

    Baumgartner, Kai; Großhans, Steffen; Schütz, Juliane; Suhm, Susanna; Hubbuch, Jürgen

    2016-09-01

    In the biopharmaceutical industry it is mandatory to know and ensure the correct protein phase state as a critical quality attribute in every process step. Unwanted protein precipitation or crystallization can lead to column, pipe or filter blocking. In formulation, the formation of aggregates can even be lethal when injected into the patient. The typical methodology to illustrate protein phase states is the generation of protein phase diagrams. Commonly, protein phase behavior is shown in dependence of protein and precipitant concentration. Despite using high-throughput methods for the generation of phase diagrams, the time necessary to reach equilibrium is the bottleneck. Faster methods to predict protein phase behavior are desirable. In this study, hydrophobic interaction chromatography retention times were correlated to crystal size and form. High-throughput thermal stability measurements (melting and aggregation temperatures), using an Optim(®)2 system, were successfully correlated to glucose isomerase stability. By using hydrophobic interaction chromatography and thermal stability determinations, glucose isomerase conformational and colloidal stability were successfully predicted for different salts in a specific pH range. PMID:27268946

  18. Factors Associated with Recruitment and Retention in Randomized Controlled Trials of Behavioral Interventions for Patients with Pediatric Type 1 Diabetes.

    PubMed

    Herbert, Linda J; Gillespie, Catherine; Monaghan, Maureen; Holmes, Clarissa; Streisand, Randi

    2016-06-01

    The purpose of this study is to describe recruitment and retention experiences from three behavioral randomized controlled trials conducted among youth with type 1 diabetes. Eligibility, recruitment, and retention data were examined. Study-specific differential study participation and loss-to-follow-up analyses assessed the relations of patient characteristics with treatment completion and 6-month retention. Multivariable logistic regression identified factors independently associated with 6-month retention among all participants. Approximately 70-92 % of randomized participants completed treatment and 58-90 % were retained for follow-up. Older patients and non-Caucasian patients were less likely to enroll. Treatment completion and 6-month retention were less likely among youth who were older, had worse baseline glycemic control, lower household income, and/or unmarried parents. Some subgroups of patients are less likely to participate in research and are more susceptible to loss-to-follow-up. More work is needed to understand the facilitators and barriers to research participation. PMID:26661924

  19. Gas retention and release behavior in Hanford single-shell waste tanks

    SciTech Connect

    Stewart, C.W.; Brewster, M.E.; Gauglitz, P.A.; Mahoney, L.A.; Meyer, P.A.; Recknagle, K.P.; Reid, H.C.

    1996-12-01

    This report describes the current understanding of flammable gas retention and release in Hanford single-shell waste tanks based on theory, experimental results, and observations of tank behavior. The single-shell tanks likely to pose a flammable gas hazard are listed and described, and photographs of core extrusions and the waste surface are included. The credible mechanisms for significant flammable gas releases are described, and release volumes and rates are quantified as much as possible. The only mechanism demonstrably capable of producing large ({approximately}100 m{sup 3}) spontaneous gas releases is the buoyant displacement, which occurs only in tanks with a relatively deep layer of supernatant liquid. Only the double-shell tanks currently satisfy this condition. All release mechanisms believed plausible in single-shell tanks have been investigated, and none have the potential for large spontaneous gas releases. Only small spontaneous gas releases of several cubic meters are likely by these mechanisms. The reasons several other postulated gas release mechanisms are implausible or incredible are also given.

  20. Retention behavior of lipids in reversed-phase ultrahigh-performance liquid chromatography-electrospray ionization mass spectrometry.

    PubMed

    Ovčačíková, Magdaléna; Lísa, Miroslav; Cífková, Eva; Holčapek, Michal

    2016-06-10

    Reversed-phase ultrahigh-performance liquid chromatography (RP-UHPLC) method using two 15cm sub-2μm particles octadecylsilica gel columns is developed with the goal to separate and unambiguously identify a large number of lipid species in biological samples. The identification is performed by the coupling with high-resolution tandem mass spectrometry (MS/MS) using quadrupole - time-of-flight (QTOF) instrument. Electrospray ionization (ESI) full scan and tandem mass spectra are measured in both polarity modes with the mass accuracy better than 5ppm, which provides a high confidence of lipid identification. Over 400 lipid species covering 14 polar and nonpolar lipid classes from 5 lipid categories are identified in total lipid extracts of human plasma, human urine and porcine brain. The general dependences of relative retention times on relative carbon number or relative double bond number are constructed and fit with the second degree polynomial regression. The regular retention patterns in homologous lipid series provide additional identification point for UHPLC/MS lipidomic analysis, which increases the confidence of lipid identification. The reprocessing of previously published data by our and other groups measured in the RP mode and ultrahigh-performance supercritical fluid chromatography on the silica column shows more generic applicability of the polynomial regression for the description of retention behavior and the prediction of retention times. The novelty of this work is the characterization of general trends in the retention behavior of lipids within logical series with constant fatty acyl length or double bond number, which may be used as an additional criterion to increase the confidence of lipid identification. PMID:27179677

  1. A Computer-Based Undergraduate Exercise Using Internet-Accessible Simulation Software for the Study of Retention Behavior and Optimization of Separation Conditions in Ion Chromatography

    ERIC Educational Resources Information Center

    Haddad, Paul R.; Shaw, Matthew J.; Madden, John E.; Dicinoski, Greg W.

    2004-01-01

    The ability to scan retention data over a wide range of eluent composition opens up the possibility of a computerized selection of the optimal separation conditions. The major characteristics of retention behavior, peak-shape effects and pH effects evident in ion chromatography (IC) using common stationary phases and eluents are illustrated.

  2. Behavior of deuterium retention and surface morphology for VPS-W/F82H

    NASA Astrophysics Data System (ADS)

    Oya, Yasuhisa; Shimada, Masashi; Tokunaga, Tomonori; Watanabe, Hideo; Yoshida, Naoaki; Hatano, Yuji; Kasada, Ryuta; Nagasaka, Takuya; Kimura, Akihiko; Okuno, Kenji

    2013-11-01

    The deuterium (D) retention for Vacuum Plasma Spray (VPS)-tungsten (W)/F82H was studied using two different implantation methods, namely D plasma exposure and D2+ implantation. The D retention for polished VPS-W/F82H after plasma exposure was found to be reduced compared to that for polycrystalline tungsten. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations indicated that porous structures around grain boundaries and the interface between VPS-W layers would be potential D diffusion paths, leading to low D retention. In the case of D2+ implantation, the shape of D2 TDS spectrum was almost the same as that for D plasma-exposed VPS-W/F82H; however, the D retention was quite high for unpolished VPS-W/F82H, indicating that most of D was trapped by the oxide layer, which was produced by the VPS process. The reduction of surface area due to the polishing process also reduces D retention for VPS-W/F82H. These results indicate that controlling the surface chemical states is important for the reduction of tritium retention for future fusion reactors.

  3. Behavior of deuterium retention and surface morphology for VPS–W/F82H

    SciTech Connect

    Yasuhisa Oya; Masashi Shimada; Tomonori Tokunaga; Hideo Watanabe; Naoaki Yoshida; Yuji Hatano; Ryuta Kasada; Takuya Nagasaka; Akihiko Kimura; Kenji Okuno

    2013-11-01

    The deuterium (D) retention for Vacuum Plasma Spray (VPS)–tungsten (W)/F82H was studied using two different implantation methods, namely D plasma exposure and View the MathML source implantation. The D retention for polished VPS–W/F82H after plasma exposure was found to be reduced compared to that for polycrystalline tungsten. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations indicated that porous structures around grain boundaries and the interface between VPS–W layers would be potential D diffusion paths, leading to low D retention. In the case of View the MathML source implantation, the shape of D2 TDS spectrum was almost the same as that for D plasma-exposed VPS–W/F82H; however, the D retention was quite high for unpolished VPS–W/F82H, indicating that most of D was trapped by the oxide layer, which was produced by the VPS process. The reduction of surface area due to the polishing process also reduces D retention for VPS–W/F82H. These results indicate that controlling the surface chemical states is important for the reduction of tritium retention for future fusion reactors.

  4. Effect of boundary conditions on measured water retention behavior within soils

    NASA Astrophysics Data System (ADS)

    Galindo-torres, S.; Scheuermann, A.; Pedroso, D.; Li, L.

    2013-12-01

    conducted to examine how the fluids are distributed inside the porous medium. This distribution is quantified by the measurement of the interfacial area which behaves also differently between the two configurations. Hassanizadeh proposed an unique relation among saturation, suction and interfacial area, which has been validated experimentally [4]. However we found that such relation is not 'unique' and instead depends on the flow and boundary conditions. While future experimental tests on these results need to be carried out, the simulated SWCC behaviors raise serious questions about the current experimental set-up for measuring the soil water retention characteristics. References. 1. Serrano, S.E., Modeling infiltration with approximate solutions to Richard's equation. Journal of Hydrologic Engineering, 2004. 9(5): p. 421-432. 2. Galindo-Torres, S.A., et al., A Lattice Boltzmann model for studying transient effects during imbibition-drainage cycles in unsaturated soils. Computer Physics Communications, 2013. 184(4): p. 1086-1093. 3. Drake, S.S., D.M. O'Carroll, and J.I. Gerhard, Wettability contrasts between fresh and weathered diesel fuels. Journal of contaminant hydrology, 2012. 4. Culligan, K.A., et al., Interfacial area measurements for unsaturated flow through a porous medium. Water Resources Research, 2004. 40(12).

  5. Investigation into the phenomena affecting the retention behavior of basic analytes in chaotropic chromatography: Joint effects of the most relevant chromatographic factors and analytes' molecular properties.

    PubMed

    Čolović, Jelena; Kalinić, Marko; Vemić, Ana; Erić, Slavica; Malenović, Anđelija

    2015-12-18

    The aim of this study was to systematically investigate the phenomena affecting the retention behavior of structurally diverse basic drugs in ion-interaction chromatographic systems with chaotropic additives. To this end, the influence of three factors was studied: pH value of the aqueous phase, concentration of sodium hexafluorophosphate, and content of acetonitrile in the mobile phase. Mobile phase pH was found to affect the thermodynamic equilibria in the studied system beyond its effects on the analytes' ionization state. Specifically, increasing pH from 2 to 4 led to longer retention times, even with analytes which remain completely protonated. An explanation for this phenomenon was sought by studying the adsorption behavior of acetonitrile and chaotropic additive onto stationary phase. It was shown that the magnitude of the developed surface potential, which significantly affects retention - increases with pH, and that this can be attributed to the larger surface excess of acetonitrile. To study how analytes' structural properties influence their retention, quantitative structure-retention modeling was performed next. A support vector machine regression model was developed, relating mobile phase constituents and structural descriptors with retention data. While the ETA_EtaP_B_RC and XlogP can be considered as molecular descriptors which describe factors affecting retention in any RP-HPLC system, TDB9p and RDF45p are molecular descriptors which account for spatial arrangement of polarizable atoms and they can clearly relate to analytes' behavior on the stationary phase surface, where the electrostatic potential develops. Complementarity of analytes' structure with that of the electric double layer can be seen as a key factor influencing their retention behavior. Structural diversity of analytes and good predictive capabilities over a range of experimental conditions make the established model a useful tool in predicting retention behavior in the studied

  6. It's Not How Much; It's How: Characteristics of Practice Behavior and Retention of Performance Skills

    ERIC Educational Resources Information Center

    Duke, Robert A.; Simmons, Amy L.; Cash, Carla Davis

    2009-01-01

    We observed 17 graduate and advanced-undergraduate piano majors practicing a difficult, three-measure keyboard passage from a Shostakovich concerto. Participants' instructions were to practice until they were confident they could play the passage accurately at a prescribed tempo in a retention test session the following day. We analyzed the…

  7. Helium irradiation effects on retention behavior of deuterium implanted into boron coating film by PCVD

    NASA Astrophysics Data System (ADS)

    Kodama, H.; Oyaidzu, M.; Yoshikawa, A.; Kimura, H.; Oya, Y.; Matsuyama, M.; Sagara, A.; Noda, N.; Okuno, K.

    2005-03-01

    Helium irradiation effects on the retention of energetic deuterium implanted into the boron coating film were investigated by means of X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found, by XPS, that the B 1s peak was shifted to lower binding energy side by He + ion irradiation and the FWHM was extended. These facts show that the some defects were introduced into the boron coating film by He + ion irradiation. From TDS experiment, the deuterium retention, especially the amount of B-D terminal bond, increased by the pre-He + ion irradiation. However, it decreased by the post-He + ion irradiation. These experimental results indicate that the B-D terminal bond was mainly influenced by the He + ion irradiation because the two neighbor B-D bonds have to dissociate simultaneously for the B-D-B bridge bond.

  8. Retention behavior of isomeric polycyclic aromatic sulfur heterocycles in reversed-phase liquid chromatography.

    PubMed

    Wilson, Walter B; Sander, Lane C; de Alda, Miren Lopez; Lee, Milton L; Wise, Stephen A

    2016-08-26

    Retention indices for 70 polycyclic aromatic sulfur heterocycles (PASHs) were determined using reversed-phase liquid chromatography (LC) on a monomeric and a polymeric C18 stationary phase. Molecular shape parameters [length, breadth, thickness (T), and length-to-breadth ratio (L/B)] were calculated for all the compounds studied. Correlations between the retention on the polymeric C18 phase and PASH geometry (L/B and T) were investigated for six specific PASH isomer groups with molecular mass (MM) 184Da, 234Da, 258Da, 284Da, 334Da, and 384Da. Similar to previous studies for polycyclic aromatic hydrocarbons (PAHs), PASH elution order on the polymeric C18 phase was generally found to follow increasing L/B values. Correlation coefficients for retention vs L/B ranged from r=0.45 (MM 184Da) to r=0.89 (MM 284Da). In the case of smaller PASHs (MM≤258Da), the location of the sulfur atom in the bay-region of the structure resulted in later than expected elution of these isomers based on L/B. In the case of the larger PASHs (MM≥284Da), nonplanarity had a significant influence on earlier than predicted elution based on L/B values. PMID:27481401

  9. The value of spontaneous alternation behavior (SAB) as a test of retention in pharmacological investigations of memory.

    PubMed

    Hughes, Robert N

    2004-09-01

    Because of its reliance on memory, the tendency for rats, mice and other animals to alternate successive choices of T- or Y-maze arms has assumed considerable popularity in pharmacological studies of spatial memory as a quick and simple measure of retention that avoids the need for extensive training and the use of conventional reinforcers. Two forms of this tendency have been utilized, namely two-trial and continuous spontaneous alternation behavior (SAB). However, as the behavior can also reflect drug-related changes in sensory/attentional, motivational and performance processes, SAB should not be unquestionably accepted as a measure of memory alone. While assessments of post-acquisition drug effects on longer term memory may be possible through the appropriate timing of drug administration, this is more problematic if SAB is used as a measure of shorter term memory. Even though SAB can be a useful index of responsiveness to novelty, its value as a measure of retention is less certain. In this latter respect, a possible alternative to SAB testing might be the recently developed form of the related procedure, responsiveness to change. PMID:15465137

  10. Retention behavior of hydrophobic organic chemicals as a function of temperature in soil leaching column chromatography.

    PubMed

    Liang, Xinmiao; Xu, Feng; Lin, Bingcheng; Su, Fan; Schramm, Karl-Werner; Kettrup, Antonius

    2002-11-01

    To study the transport mechanism of hydrophobic organic chemicals (HOCs) and the energy change in soil/solvent system, a soil leaching column chromatographic (SLCC) experiment at an environmental temperature range of 20-40 degrees C was carried out, which utilized a reference soil (SP 14696) packed column and a methanol-water (1:4 by volume ratio) eluent. The transport process quickens with the increase of column temperature. The ratio of retention factors at 30 and 40 degrees C (k'30/k'40) ranged from 1.08 to 1.36. The lower enthalpy change of the solute transfer in SLCC (from eluent to soil) than in conventional reversed-phase liquid chromatography (e.g., from eluent to C18) is consistent with the hypothesis that HOCs were dominantly and physically partitioned between solvent and soil. The results were also verified by the linear solvation energy relationships analysis. The chief factor controlling the retention was found to be the solute solvophobic partition, and the second important factor was the solute hydrogen-bond basicity, while the least important factors were the solute polarizability-dipolarity and hydrogen-bond acidity. With the increase of temperature, the contributions of the solute solvophobic partition and hydrogen-bond basicity gradually decrease, and the latter decreases faster than the former. PMID:12430644

  11. Retention behavior of alkyl-substituted polycyclic aromatic sulfur heterocycles in reversed-phase liquid chromatography.

    PubMed

    Wilson, Walter B; Sander, Lane C; de Alda, Miren Lopez; Lee, Milton L; Wise, Stephen A

    2016-08-26

    Retention indices for 79 alkyl-substituted polycyclic aromatic sulfur heterocycles (PASHs) were determined by using reversed-phase liquid chromatography (LC) on a monomeric and polymeric octadecylsilane (C18) stationary phase. Molecular shape parameters [length, breadth, thickness (T), and length-to-breadth ratio (L/B)] were calculated for all the compounds studied. Based on separations of isomeric methylated polycyclic aromatic hydrocarbons on polymeric C18 phases, alkyl-substituted PASHs are expected to elute based on increasing L/B ratios. However, the correlation coefficients had a wide range of values from r=0.43 to r=0.93. Several structural features besides L/B ratios were identified to play an important role in the separation mechanism of PASHs on polymeric C18 phases. First, the location of the sulfur atom in a bay-like-region results in alkylated-PASHs being more retentive than non-bay-like-region alkylated-PASHs, and they elute later than expected based on L/B value. Second, the placement of the alkyl group in the k region of the structure resulted in a later elution than predicted by L/B. Third, highly nonplanar methyl-PASHs (i.e., 1-Me and 11-MeBbN12T) elute prior to the parent PASH (BbN12T). PMID:27477517

  12. Efficacy of Cognitive Behavioral Therapy on Opiate Use and Retention in Methadone Maintenance Treatment in China: A Randomised Trial

    PubMed Central

    Du, Jiang; Chen, Hanhui; Li, Zhibin; Ling, Walter; Zhao, Min

    2015-01-01

    Aims Methadone maintenance treatment (MMT) is widely available in China; but, high rates of illicit opiate use and dropout are problematic. The aim of this study was to test whether cognitive behavioral therapy (CBT) in conjunction with MMT can improve treatment retention and reduce opiate use. Method A total of 240 opiate-dependent patients in community-based MMT clinics were randomly assigned to either weekly CBT plus standard MMT (CBT group, n=120) or standard MMT (control group, n=120) for 26 weeks. The primary outcomes were treatment retention and opiate-negative urine test results at 12 weeks and 26 weeks. The secondary outcomes were composite scores on the Addiction Severity Index (ASI) and total scores on the Perceived Stress Scale (PSS) at 12 weeks and 26 weeks. Results Compared to the control group in standard MMT, the CBT group had higher proportion of opiate-negative urine tests at both 12 weeks (59% vs. 69%, p<0.05) and 26 weeks (63% vs. 73%, p<0.05); however, the retention rates at 12 weeks (73.3% vs. 74.2%, p=0.88) and 26 weeks were not different (55.8% vs. 64.2%, p=0.19) between the two groups. At both 12 and 26 weeks, all of the ASI component scores and PSS total scores in the CBT group and control group decreased from baseline; but the CBT group exhibited more decreases in ASI employment scores at week 26 and more decrease in the PSS total score at week 12 and week 26. Conclusions CBT counselling is effective in reducing opiate use and improving employment function and in decreasing stress level for opiate-dependent patients in MMT in China. Trial Registration ClinicalTrials.gov NCT01144390 PMID:26107818

  13. Effects of comprehensive function of factors on retention behavior of microparticles in gravitational field-flow fractionation.

    PubMed

    Guo, Shuang; Qiu, Bai-Ling; Zhu, Chen-Qi; Yang, Ya-Ya Gao; Wu, Di; Liang, Qi-Hui; Han, Nan-Yin

    2016-09-15

    Gravitational field-flow fractionation (GrFFF) is a useful technique for separation and characterization for micrometer-sized particles. Elution behavior of micrometer-sized particles in GrFFF was researched in this study. Particles in GrFFF channel are subject to hydrodynamic lift forces (HLF), fluid inertial forces and gravity, which drive them to different velocities by carrier flow, resulting in a size-based separation. Effects of ionic strength, flow rate and viscosity as well as methanol were investigated using polystyrene latex beads as model particles. This study is devoted to experimental verification of the effect of every factor and their comprehensive function. All experiments were performed to show isolated influence of every variable factor. The orthogonal design test was used to evaluate various factors comprehensively. Results suggested that retention ratio of particles increases with increasing flow rate or the viscosity of carrier liquid by adjusting external forces acting on particles. In addition, retention ratio increases as ionic strength decreases because of decreased electrostatic repulsion between particles and channel accumulation wall. As far as methanol, there is no general trend due to the change of both density and viscosity. On the basis of orthogonal design test it was found that viscosity of carrier liquid plays a significant role in determining resolution of micrometer-sized particles in GrFFF. PMID:27447927

  14. A Study of Middle School Principal Behaviors and Their Impact on Teacher Retention

    ERIC Educational Resources Information Center

    Martin, Todd

    2011-01-01

    This dissertation was designed to investigate the causes behind teacher turnover and the connection between principal behavior, teacher working conditions, and rates of teacher turnover. In particular, this study examined behaviors that teachers in three North Carolina middle schools felt their principals displayed that helped encourage them to…

  15. An Empirical Examination of Outdoor Behavioral Healthcare Field Instructor Job-Related Stress and Retention

    ERIC Educational Resources Information Center

    Marchand, Genevieve; Russell, Keith C.; Cross, Reid

    2009-01-01

    The purpose of this study was to collect and analyze demographic characteristics and job related difficulties experienced by field instructors in outdoor behavioral healthcare programs which utilized wilderness therapy as well as other treatment modalities. Three state-licensed outdoor behavioral healthcare programs in the United States provided a…

  16. Retention behavior of long chain quaternary ammonium homologues and related nitroso-alkymethylamines

    USGS Publications Warehouse

    Abidi, S.L.

    1985-01-01

    Several chromatographic methods have been utilized to study the retentionbehavior of a homologous series of n-alkylbenzyldimethylammonium chlorides (ABDAC) and the corresponding nitroso-n-alkylmethylamines (NAMA). Linear correlation of the logarithmic capacity factor (k') with the number of carbons in the alkyl chain provides useful information on both gas chromatographic (GC) and high-performance liquid chromatographich (HPLC) retention parameters of unknown components. Under all conditions empolyed, GC methodology has proved effective in achieving complete resolution of the homologous mixture of NMA despite its obvious inadequacy in the separation of E-Z configurational isomers. Conversely, normal-phase HPLC on silica demonstrates that the selectivity (a) value for an E-Z pair is much higher than that for an adjacent homologous pair. In the reversed-phase HPLC study, three different silica-based column systems were examined under various mobile phase conditions. The extent of variation in k' was found to be a function of the organic modifier, counter-ion concentration, eluent pH, nature of counter-ion, and the polarity and type of stationary phase. The k'—[NaClO4] profiles showed similar trends between the ABDAC and the NAMA series, supporting the dipolar electronic structures of the latter compounds. Mobile phase and stationary phase effects on component separation are described. The methodology presented establishes the utility of HPLC separation techniques as versatile analytical tools for practical application.

  17. Behavior Management Skills as Predictors of Retention among South Texas Special Educators

    ERIC Educational Resources Information Center

    Mitchell, Ann; Arnold, Mitylene

    2004-01-01

    A survey of South Texas Special Education teachers was conducted to determine how they perceived their behavior management skills in the classroom and what effect, if any, this had on their job satisfaction. The majority of teachers were confident in their ability to accomplish the management demands of the classroom. The teachers who showed the…

  18. A Preliminary Study of Bully and Victim Behavior in Old-for-Grade Students: Another Potential Hidden Cost of Grade Retention or Delayed School Entry

    ERIC Educational Resources Information Center

    Crothers, Laura M.; Schreiber, James B.; Schmitt, Ara J.; Bell, G. Ronald; Blasik, Jessica; Comstock, Leigh A.; Greisler, Michael J.; Keener, Dana; King, Jamie M.; Lipinski, John

    2010-01-01

    Mounting evidence suggests that being an old-for-grade student, as a result of grade retention or delayed school entry, is related to negative outcomes across various domains of functioning. No known study has examined the relations between old-for-grade status and specific childhood/adolescent bully and victim behaviors. The first purpose of this…

  19. Forced egg retention and oviposition behavior of malaria, dengue and filariasis vectors to a topical repellent diethyl-phenylacetamide.

    PubMed

    Seenivasagan, T; Iqbal, S Thanvir; Guha, Lopamudra

    2015-07-01

    Egg retention and oviposition behavior of four species of mosquito vectors viz., Anopheles stephensi, Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus to a topical insect repellent diethyl-phenylacetamide (DEPA) at 0.1-1000 mg/L was investigated under laboratory conditions. Based on oviposition activity indices, DEPA demonstrated concentration dependent oviposition deterrent effect to A. stephensi (-0.18 to -0.97), A. aegypti (-0.18 to -0.91) and A. albopictus (-0.50 to -0.98) females. In contrast, positive oviposition response by C. quinquefasciatus (+0.39 and +0.70) was observed respectively at 0.1 and 1 ppm, while 10 ppm of DEPA on water received 50% lesser egg rafts than control. Gravid Culex females laid no egg rafts at 100 and 1000 ppm DEPA treated bowls effecting 100% oviposition deterrence. Test mosquito females deposited most of their eggs (> 90%) in the absence of repellent odour, while DEPA odour on water surface forced them to retain huge numbers of eggs. Females of A. aegypti, A. albopictus and A. stephensi retained 49, 67 and 50% of total eggs, respectively throughout the experiment. Egg retention by Culex females due to DEPA on the water surface was ca. 65%, equivalent to 4 egg rafts. Therefore, DEPA at lower concentrations could effectively disturb the oviposition by these vectors. Application of repellents in small water bodies would help in reducing the population build up of mosquitoes near human households and could be useful in the integrated management of mosquito vectors. PMID:26245028

  20. Prevention des Toxicomanies Aupres des Filles avec des Problemes de Comportement: Effets a Court Terme (Prevention of Drug Addiction in Girls with Behavior Problems: Short-Term Effects).

    ERIC Educational Resources Information Center

    Vitaro, Frank; And Others

    1992-01-01

    This article, written in French, describes and evaluates the first phase of a program to prevent drug addiction among 110 fifth-grade girls with behavior problems in Montreal (Quebec, Canada). Evaluation of the instructional program showed positive results for student knowledge level, attitudes, and behaviors and supported program continuation…

  1. Retention behavior of C1-C6 aliphatic monoamines on anion-exchange and polymethacrylate resins with heptylamine as eluent.

    PubMed

    Ohta, Kazutoku; Ohashi, Masayoshi; Jin, Ji-Ye; Takeuchi, Toyohide; Fujimoto, Chuzo; Choi, Seong-Ho; Ryoo, Jae Jeong; Lee, Kwang-Pill

    2004-06-11

    Retention behavior of C1-C6, aliphatic monoamines (methylamine, ethylamine, propylamine, butylamine, amylamine and hexylamine) on columns (150 mm x 6 mm i.d.) packed with various anion-exchange resins (styrene-divinylbenzene (PS-DVB) copolymer-based strongly basic anion-exchange resin: TSKgel SAX, polymethacrylate-based strongly basic anion-exchange resin: TSKgel SuperQ-5PW and polymethacrylate-based weakly basic anion-exchange resin: TSKgel DEAE-5PW) and unfunctionized polymethacrylate resins (TSKgel G5000PW and TSKgel G3000PWXL) was investigated with basic solutions (sodium hydroxide and heptylamine) as the eluents. Due to strongly electrostatic repulsion (ion-exclusion effect) between these anion-exchange resins and these amines, peak resolution between these amines on these anion-exchange resin columns was unsatisfactory with both sodium hydroxide and heptylamine as the eluents. In contrast, these polymethacrylate resins were successfully applied as the stationary phases for the separation of these C1-C6 amines with heptylamine as eluent, because of both small hydrophobicity and small cation-exchange ability of these resins. Excellent simultaneous separation, highly sensitive conductimetric detection and symmetrical peaks for these C1-C6 amines were achieved on the TSKgel G3000PWXL column in 35 min with 5 mM heptylamine at pH 11.1 as the eluent. PMID:15250421

  2. Phenomenon of dual- and single-retention behaviors of solutes and its validation by computational simulation in linear programmed temperature gas chromatography.

    PubMed

    Wu, Liejun; Duan, Xiaojuan; Liu, Chuanyu; Zhang, Guangxiang; Li, Qing X

    2016-07-01

    The current theory of programmed temperature gas chromatography considers that solutes are focused by the stationary phase at the column head completely and does not explicitly recognize the different effects of initial temperature (To ) and heating rate (rT ) on the retention time or temperature of a homologue series. In the present study, n-alkanes, 1-alkenes, 1-alkyl alcohols, alkyl benzenes, and fatty acid methyl esters standards were used as model chemicals and were separated on two nonpolar columns, one moderately polar column and one polar column. Effects of To and rT on the retention of nonstationary phase focusing solutes can be explicitly described with isothermal and cubic equation models, respectively. When the solutes were in the stationary phase focusing status, the single-retention behavior of solutes was observed. It is simple, dependent upon rT only and can be well described by the cubic equation model that was visualized through four sequential slope analyses. These observed dual- and single-retention behaviors of solutes were validated by various experimental data, physical properties, and computational simulation. PMID:27241084

  3. Strength retention behavior of oriented PLLA, 96L/4D PLA, and 80L/20D,L PLA

    PubMed Central

    Huttunen, Mikko; Kellomäki, Minna

    2013-01-01

    The strength retention characteristics of oriented semicrystalline polylactides were monitored during hydrolytic degradation in vitro. The effects of the polymer type, the material’s initial inherent viscosity (iv), the sample diameter and the residual monomer content on strength retention were analyzed. The analyzed polylactides had similar, but not identical, strength retention characteristics. It was concluded that a higher degree of initial crystallinity was a major variable determining the earlier and more profound strength loss of PLLA than 96L/4D PLA and 80L/20 D,L PLA. Samples with a higher initial iv were found to have a longer strength retention time than lower iv samples. Size-dependency was observed, as the strength retention time was shorter for the smaller diameter samples. This size-dependency was caused by faster iv decay. The amount of residual monomer content had a remarkable impact on strength retention. Neither the sample diameter, initial iv or residual monomer content were found to have an effect on the iv range in which there was a rapid decline in strength properties. Therefore, it was concluded that the inherent viscosity and/or molecular weight of oriented PLLA, 96L/4D PLA and 80L/20 D,L PLA is a major variable determining the strength retention of these materials. PMID:24025528

  4. Increased weight gain, nitrogen retention and muscle protein synthesis following treatment of diabetic rats with insulin-like growth factor (IGF)-I and des(1-3)IGF-I.

    PubMed Central

    Tomas, F M; Knowles, S E; Owens, P C; Read, L C; Chandler, C S; Gargosky, S E; Ballard, F J

    1991-01-01

    We have examined the effects of infusing recombinant human growth hormone (hGH), insulin-like growth factor-I (IGF-I), the truncated IGF-I analogue, des(1-3)IGF-I, and insulin over a 7-day period in streptozotocin-induced diabetic rats. IGF-I at a dose of 1.05 or 1.08 mg/kg per day in two experiments increased body weight and nitrogen retention above those of vehicle-infused controls to about 30% of the improvement achieved with 25 or 30 units of insulin/kg per day, but only in the second experiment were the differences statistically significant (P less than 0.05). A 2.5-fold higher IGF-I dose, or des(1-3)IGF-I at 1.08 mg/kg per day, gave effects that were approx. 70% of those obtained with insulin. hGH at 1.38 mg/kg per day was not effective. The IGF peptides, unlike insulin, did not ameliorate the diabetic glucosuria. The improvements in nitrogen balance could be accounted for in part by increases in muscle protein synthesis. Muscle protein breakdown, as assessed by 3-methylhistidine excretion, was inhibited by insulin, but not by the IGF peptides. Carcass fat increased substantially following insulin administration. This did not occur with the IGF peptides, suggesting that IGF predominantly stimulates the growth of lean tissue. IGF-I concentrations and IGF-I-binding proteins in plasma were increased by IGF-I, especially at the higher dose, whereas hGH produced only a transient increase in IGF-I. Des(1-3)IGF-I induced binding proteins, but had only a slight effect on measured IGF-I concentrations. We conclude that IGF peptides stimulate muscle protein synthesis and improve nitrogen balance in diabetes without obviously influencing the abnormal carbohydrate metabolism. Moreover, des(1-3)IGF-I is at least as potent as the full-length IGF-I. Images Fig. 2. PMID:1710892

  5. The effect of voice ambulatory biofeedback on the daily performance and retention of a modified vocal motor behavior in participants with normal voices

    PubMed Central

    Van Stan, Jarrad H.; Mehta, Daryush D.; Hillman, Robert E.

    2015-01-01

    Purpose Ambulatory biofeedback has potential to improve carryover of newly-established vocal motor behaviors into daily life outside of the clinic and warrants systematic research that is lacking in the literature. This proof-of-concept study was designed to establish an empirical basis for future work in this area by formally assessing whether ambulatory biofeedback reduces daily vocal intensity (performance) and the extent to which this change remains after biofeedback removal (retention). Method Six participants with normal voices wore the KayPENTAX Ambulatory Phonation Monitor for three baseline days followed by four days with biofeedback provided on odd days. Results Compared to baseline days, participants exhibited a statistically significant decrease in mean vocal intensity (4.4 dB) and an increase in compliance (16.8 percentage points) when biofeedback was provided above a participant-specific intensity threshold. After biofeedback removal, mean vocal intensity and compliance reverted back to baseline levels. Conclusions These findings suggest that although current ambulatory biofeedback approaches have potential to modify a vocal motor behavior, the modified behavior may not be retained after biofeedback removal. Future work calls for the testing of more innovative ambulatory biofeedback approaches based on motor control and learning theories to improve retention of a desired vocal motor behavior. PMID:25765862

  6. Material and Social Incentives to Participation in Behavioral Interventions: A Meta-Analysis of Gender Disparities in Enrollment and Retention in Experimental Human Immunodeficiency Virus Prevention Interventions

    PubMed Central

    Durantini, Marta R.; Albarracín, Dolores

    2013-01-01

    Objective A meta-analysis was conducted to test theoretical hypotheses about the predictors of enrollment and completion of condom-use-promotion interventions among men and women. Design A meta-analysis summarized research reports of the efficacy of experimental interventions on human immunodeficiency virus (HIV) prevention. Main Outcome Measures The outcome measure consisted of (a) a measure of participation, obtained by subtracting the actual number of participants from the number of the invited people, and (b) a measure of retention was obtained by subtracting the number of participants who completed the intervention from the number of commencers. Results Experimental interventions providing instrumental and financial resources (e.g., payments) increased initiation and retention more among predominantly male samples, whereas experimental interventions using group formats increased initiation and retention more among predominantly female samples. These patterns remained while controlling for past condom use, other HIV-risk behaviors, and demographics associated with gender composition. Conclusion People seek out HIV-prevention interventions to fulfill gender-specific needs, and these differences must be taken into account in the design of HIV-prevention interventions. PMID:19751090

  7. Behavior of PAH/mineral associations during thermodesorption: impact for the determination of mineral retention properties towards PAHs.

    PubMed

    Biache, Coralie; Lorgeoux, Catherine; Saada, Alain; Faure, Pierre

    2015-05-01

    Polycyclic aromatic hydrocarbons (PAHs) associated with two minerals (silica sand and bentonite) presenting opposite retention properties were analyzed with a thermodesorption (Td)-GC-MS coupling in order to validate this technique as a new and rapid way to evaluate the solid sorption properties. Two analysis modes were used, evolved gas analysis (EGA) and Td with cryo-trap. EGA allowed a real-time monitoring of the compounds desorbed during a temperature program and gave a first screening of the samples while Td gave more precise indications on compound abundances for selected temperature ranges. When associated with silica sand, PAHs were released at relatively low temperatures (<300 °C) close to corresponding boiling point, whereas for the PAH/bentonite mixture, PAHs were desorbed at much higher temperatures; they were also present in much lower abundance and were associated with mono-aromatic compounds. With bentonite, the PAH abundances decreased and the mono-aromatics increased with the increasing PAH molecular weight. These results indicated a clear PAH retention by the bentonite due to polymerization, followed by a thermal cracking at higher temperatures. The Td-GC-MS was proven to efficiently underline differences in retention properties of two minerals, and this study highlights the great potential of this technique to evaluate compound/matrix bond strength and interaction. PMID:25772555

  8. Lipophilicity indices derived from the liquid chromatographic behavior observed under bimodal retention conditions (reversed phase/hydrophilic interaction): application to a representative set of pyridinium oximes.

    PubMed

    Voicu, Victor; Sârbu, Costel; Tache, Florentin; Micăle, Florina; Rădulescu, Ştefan Flavian; Sakurada, Koichi; Ohta, Hikoto; Medvedovici, Andrei

    2014-05-01

    The liquid chromatographic behavior observed under bimodal retention conditions (reversed phase and hydrophilic interaction) offers a new basis for the determination of some derived lipophilicity indices. The experiments were carried out on a representative group (30 compounds) of pyridinium oximes, therapeutically tested in acetylcholinesterase reactivation, covering a large range of lipophilic character. The chromatographic behavior was observed on a mixed mode acting stationary phase, resulting from covalent functionalization of high purity spherical silica with long chain alkyl groups terminated by a polar environment created through the vicinal diol substitution at the lasting carbon atoms (Acclaim Mixed Mode HILIC 1 column). Elution was achieved by combining different proportions of 5 mM ammonium formiate solutions in water and acetonitrile. The derived lipophilicity indices were compared with logP values resulting from different computational algorithms. The correlations between experimental and computed data sets are significant. To obtain a better insight on the transition from reversed phase to hydrophilic interaction retention mechanisms, the variation of the thermodynamic parameters determined through the van׳t Hoff approach was also discussed. PMID:24720980

  9. Retention of Motor Skills: Review.

    ERIC Educational Resources Information Center

    Schendel, J. D.; And Others

    A summary of an extensive literature survey deals with the variables known or suspected to affect the retention of learned motor behaviors over lengthy no-practice intervals. Emphasis was given to research conducted by or for the military. The variables that may affect the retention of motor skills were dichotomized into task variables and…

  10. American Recovery and Reinvestment Act of 2009. Interim Report on Customer Acceptance, Retention, and Response to Time-Based Rates from the Consumer Behavior Studies

    SciTech Connect

    Cappers, Peter; Hans, Liesel; Scheer, Richard

    2015-06-01

    Time-based rate programs1, enabled by utility investments in advanced metering infrastructure (AMI), are increasingly being considered by utilities as tools to reduce peak demand and enable customers to better manage consumption and costs. There are several customer systems that are relatively new to the marketplace and have the potential for improving the effectiveness of these programs, including in-home displays (IHDs), programmable communicating thermostats (PCTs), and web portals. Policy and decision makers are interested in more information about customer acceptance, retention, and response before moving forward with expanded deployments of AMI-enabled new rates and technologies. Under the Smart Grid Investment Grant Program (SGIG), the U.S. Department of Energy (DOE) partnered with several utilities to conduct consumer behavior studies (CBS). The goals involved applying randomized and controlled experimental designs for estimating customer responses more precisely and credibly to advance understanding of time-based rates and customer systems, and provide new information for improving program designs, implementation strategies, and evaluations. The intent was to produce more robust and credible analysis of impacts, costs, benefits, and lessons learned and assist utility and regulatory decision makers in evaluating investment opportunities involving time-based rates. To help achieve these goals, DOE developed technical guidelines to help the CBS utilities estimate customer acceptance, retention, and response more precisely.

  11. Effects of Ionic Strength on Bacteriophage MS2 Behavior and Their Implications for the Assessment of Virus Retention by Ultrafiltration Membranes ▿

    PubMed Central

    Furiga, Aurelie; Pierre, Gwenaelle; Glories, Marie; Aimar, Pierre; Roques, Christine; Causserand, Christel; Berge, Mathieu

    2011-01-01

    Bacteriophage MS2 is widely used as a surrogate to estimate pathogenic virus elimination by membrane filtration processes used in water treatment. Given that this water technology may be conducted with different types of waters, we focused on investigating the effects of ionic strength on MS2 behavior. For this, MS2 was analyzed while suspended in solutions of various ionic strengths, first in a batch experiment and second during membrane ultrafiltration, and quantified using (i) quantitative reverse transcriptase PCR (qRT-PCR), which detects the total number of viral genomes, (ii) qRT-PCR without the RNA extraction step, which reflects only particles with a broken capsid (free RNA), and (iii) the PFU method, which detects only infectious viruses. At the beginning of the batch experiments using solutions containing small amounts of salts, losses of MS2 infectivity (90%) and broken particles (20%) were observed; these proportions did not change during filtration. In contrast, in high-ionic-strength solutions, bacteriophage kept its biological activity under static conditions, but it quickly lost its infectivity during the filtration process. Increasing the ionic strength decreased both the inactivation and the capsid breakup in the feed suspension and increased the loss of infectivity in the filtration retentate, while the numbers of MS2 genomes were identical in both experiments. In conclusion, the effects of ionic strength on MS2 behavior may significantly distort the results of membrane filtration processes, and therefore, the combination of classical and molecular methods used here is useful for an effective validation of the retention efficiency of ultrafiltration membranes. PMID:21075898

  12. Urinary Retention

    MedlinePlus

    ... the bladder does not empty completely. A health care provider performs this test during an office visit. The patient often receives ... urodynamic tests to diagnose urinary retention. The health care provider will perform these tests during an office visit. For tests that use ...

  13. Occurrence of pharmaceuticals and endocrine disruptors in raw sewage and their behavior in UASB reactors operated at different hydraulic retention times.

    PubMed

    Queiroz, F B; Brandt, E M F; Aquino, S F; Chernicharo, C A L; Afonso, R J C F

    2012-01-01

    This work investigated the occurrence of pharmaceuticals and endocrine disrupting compounds (EDCs) in raw sewage (from Belo Horizonte city, Minas Gerais state, Brazil) and assessed their behavior in demo-scale upflow anaerobic sludge blanket reactors (UASB reactors) operated at different hydraulic retention times (HRT). The dissolved concentration of the studied micropollutants in the raw and treated sewage was obtained using solid phase extraction (SPE) followed by analysis in a liquid chromatography system coupled to a hybrid high resolution mass spectrometer consisting of an ion-trap and time of flight (LC-MS-IT-TOF). The natural (estradiol) and synthetic (ethinylestradiol) estrogens were hardly detected; when present, however, their concentrations were lower than the method quantification limits. The concentrations of bisphenol A and miconazole in raw sewage were similar to that reported in the literature (around 200 ng L⁻¹ and hardly detected, respectively). The antibiotics sulfamethoxazole (median 13.0 ng L⁻¹) and trimethoprim (median 61.5 ng L⁻¹), and the other pharmaceutical compounds (diclofenac and bezafibrate, with median 99.9 and 94.4 ng L⁻¹, respectively) were found in lower concentrations when compared with reports in the literature, which might indicate a lower consumption of such drugs in Brazil. The UASB reactors were inefficient in the removal of bisphenol A, and led to an increased concentration of nonylphenol in the effluent. The anaerobic reactors were also inefficient in the removal of diclofenac, and led to a partial removal of bezafibrate; whereas, for sulfamethoxazole there seemed to be a direct relationship between the HRT and removal efficiencies. For trimethoprim the sludge retention time (SRT) seemed to play an important role, although it was only partially removed in the UASB reactors. PMID:23109571

  14. [Influences of ion-suppressors on retention behaviors of nine food additives in reversed-phase high performance liquid chromatographic separation].

    PubMed

    Zhao, Yonggang; Chen, Xiaohong; Li, Xiaoping; Yao, Shanshan; Jin, Micong

    2011-10-01

    The influences of ion-suppressors on retention behaviors of nine food additives, i.e., acesulfame, saccharin, caffeine, aspartame, benzoic acid, sorbic acid, stevioside, dehydroacetic acid and neotame in reversed-phase high performance liquid chromatographic (RP-HPLC) separation were investigated. The organic modification effects of acids, i. e. , trifluoroacetic acid (TFA) and buffer salts, i. e. , TFA-ammonium acetate (AmAc) were studied emphatically. The relationships between retention factors of solutes and volume percentages of ion-suppressors in the mobile phase systems of acetonitrile-TFA aqueous solution and acetonitrile-TFA-AmAc aqueous solution were quantitatively established, separately. The separation of nine food additives was completed by a gradient elution with acetonitrile-TFA (0.01%, v/v)-AmAc (2. 5 mmol/L) aqueous solution as the mobile phases. An RP-HPLC method was established for the simultaneous determination of nine food additives in red wine. In the range of 10. 0 - 100. 0 mg/L, nine food additives showed good linearity with the correlation coefficients ( r2 ) larger than 0. 999 1. The limits of detection (LODs) were in the range of 0. 33 - 2. 36 mg/L and the limits of quantification (LOQs) were in the range of 1. 11 - 7. 80 mg/L. The spiked recoveries were between 87. 61% and 108. 4% with the relative standard deviations (RSDs) of 2. 2% -9. 4%. These results are of referential significance for the rapid establishment and accu- rate optimization of RP-HPLC separation for the simultaneous determination of food additives in other foods. PMID:22268355

  15. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect

    Ramanathan Sampath

    2005-03-31

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2004 to March 31, 2005 which covers the fifth six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. During this reporting period, electrical conductivity measurements for bottom, and top phases, as well as bottom/top, and top/bottom conjugate pair phases of the ethylbenzene/water/ethanol system were performed for various ethanol volume percentage of the mixtures starting from 2% to 60%. Preliminary findings are that electrical conductivity of the bottom phase decreased as ethanol volume fraction of the mixture increased. Conductivity of the top phase was small and remained almost the same for variations in ethanol volume fraction of the mixture. Conductivity of the emulsion of the conjugate pair phases decreased as the fraction of volume of the top phase was increased and vice versa. Also inversion phenomena was observed. Detailed analyses are in progress including the prediction of conductivity data using the theoretical model already developed in this project.

  16. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect

    Ramanathan Sampath

    2005-09-30

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period April 01, 2005 to September 30, 2005 which covers the sixth six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. In the last reporting period, electrical conductivity measurements for bottom/top, and top/bottom conjugate pair phases of the ethylbenzene/water/ethanol system were performed for various ethanol volume percentage in the mixture: 2,10,20,33,43,50, and 56. During this reporting period, prediction of electrical conductivity data obtained in the past was conducted employing a theoretical model already developed in this project. Results of the comparisons for 2, and 10% ethanol volume in the mixture are presented here. A good agreement was obtained between the predicted emulsion conductivities and the measured values. To date about 99% of the proposed work has been completed. Conductivity prediction for 56% ethanol volume in the mixture is in progress. Following this prediction, a final report will be developed describing the research activities conducted through the entire project period including results and conclusions.

  17. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect

    Ramanathan Sampath

    2003-03-31

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2002 to April 01, 2003 which covers the first six months of the project. Presently work is in progress to characterize phase and emulsion behavior for condensate/water/ethanol system. Temperature and salinity scans are planned to identify the optimal salinity and temperature, and the temperature and salinity intervals in which all three phases coexist for this system. Test matrix to perform salinity and temperature scans has been established. Supply requests to obtain hydrocarbons, surfactant, etc., were processed and supplies obtained. Current literature in the subject area, and modeling efforts that were established in our previous studies to predict electrical conductivities and inversion phenomena were reviewed. Based on the review a computer model to predict electrical conductivities of the ethylbenzene (that has the equivalent carbon number of the condensate)/water/ethanol system is being developed. These activities resulted in one published conference abstract during this reporting period.

  18. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect

    Ramanathan Sampath

    2004-03-31

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2003 to March 31, 2004 which covers the third six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. During this reporting period, temperature scans were performed mixing equal volumes of ethylbenzene and 10mM NaCl water with various concentrations of ethanol ranging from 2 to 70 vol%. For the range of temperatures tested (2 to 70 C), results indicate that temperature is invariant and produced a single phase for ethanol concentrations greater than 60 vol%. For ethanol concentrations less than 60 vol%, only two phases were obtained with aqueous rich bottom phase more in volume than that of the ethylbenzene rich top phase. Linear coreflooding experiments were completed by our industrial partner in this project, Surtek, CO, to measure the condensate recovery in flooding processes. It was found about 30% ethylbenzene recovery was obtained by the waterflooding, however, 2wt% ethanol flooding did not produce incremental recovery of the ethylbenzene. Radial coreflooding with ethanol injection prior to water injection is in progress to assess the effectiveness of the surfactant flooding in the recovery of condensate.

  19. Investigation of Phase and Emulsion Behavior, Surfactant Retention and Condensate Recovery for Condensate/Water/Ethanol Mixtures

    SciTech Connect

    Ramanathan Sampath

    2004-09-30

    This semi-annual technical progress report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period April 01, 2004 to September 30, 2004 which covers the fourth six months of the project. Presently work is in progress to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number is used as the model condensate. During this reporting period, work was under way and the electrical conductivity experimental system was set up at the Atlanta University Center. Following the set-up of the emulsion measurement system, the electronic instruments and data acquisition modules involved were tested for proper operation of the system. Then, the conductivity output was normalized with that obtained for 10mM NaCl water. Radial coreflooding experiments with ethanol injection prior to and after water injection were completed to assess the effectiveness of the surfactant flooding in the recovery of condensate by our industrial partner, Surtek, CO, in this reporting period. In Run 1, 10 mM NaCl without ethanol injection recovered 31.5% of the initial ethyl benzene saturation. Injection of ethanol following 10 mM NaCl produced a tertiary ethyl benzene bank with maximum ethyl benzene cuts of 32%. In Run 2, 50 vol% of pure (100%) ethanol was injected and flowed through the Berea sandstone after Ethyl Benzene Saturation. 69% of the initial ethyl benzene was recovered. Results of the radial corefloods are very encouraging. Emulsion conductivity measurements for conjugate pair phases are in progress at Morehouse.

  20. Transport, retention, and long-term release behavior of ZnO nanoparticle aggregates in saturated quartz sand: Role of solution pH and biofilm coating

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The transport, retention, and long-term fate of zinc oxide nanoparticles (ZnO-NPs) were investigated in saturated, bare and biofilm (Pseudomonas putida) coated sand packed columns. Almost complete retention of ZnO-NPs occurred in bare and biofilm coated sand when the influent solution pH was 9 and t...

  1. INVESTIGATION OF PHASE AND EMULSION BEHAVIOR, SURFACTANT RETENTION, AND CONDENSATE RECOVERY FOR CONDENSATE/WATER/ETHANOL MIXTURES

    SciTech Connect

    Ramanathan Sampath

    2005-12-01

    This final technical report describes work performed at Morehouse College under DOE Grant No. DE-FG26-02NT15447 during the period October 01, 2002 to September 30, 2005, which covers the total performance period of the project. During this period, work was conducted to characterize phase and emulsion behavior for ethylbenzene/water/ethanol system. Ethylbenzene that has the equivalent carbon number was used as the model condensate. Salinity scans were performed for 0, 5, 10, 20, 50, 100, 250, 500, and 1000 mM salt concentrations at room temperature to identify the optimal salinity and salinity intervals in which all phases coexisted. It was found that only two phases formed, and salinity has no significant effect in the volumes of the phases formed. Experiments were repeated at 30 C and observed salinity has no effect at higher temperatures as well. Following the salinity experiments, measurements were made with 10mM NaCl water for surfactant concentrations from 2 to 70 volume percent at room temperature. It was found that only two phases were formed upto 60 vol% concentration of the surfactant. Above 60 vol% surfactant, the mixture produced only a single phase. Experiments were repeated from 2 to 70 C and observed that temperature has no significant effect on the number of phases formed. At the temperatures and surfactant concentration tested, volume fraction of the aqueous bottom phase was found to be larger than that of the top phase. Electrical conductivity measurements were then conducted for bottom/top, and top/bottom conjugate pair phases of the ethylbenzene/water/ethanol system formed by mixing ethanol at various volume percentages including 2,10,33,and 56% while keeping the volumes of ethylbenzene and water the same in the mixture. Electrical conductivity of the bottom phase decreased as ethanol volume fraction in the mixture increased. Conductivity of the top phase was found small and remained almost the same for variations in ethanol volume fraction in

  2. Pulmonary retention of coal dusts

    SciTech Connect

    Morrow, P.E.; Gibb, F.R.; Beiter, H.; Amato, F.; Yuile, C.; Kilpper, R.W.

    1980-01-01

    The principal objectives of this study were: to determine, quantitatively, coal dust retention times in the dog lung; to test the appropriateness of a pulmonary retention model which incorporates first order rate coefficients obtained from in vitro and in vivo experiments on neutron-activated coal; to acquire a temporal description of the pulmonary disposition of the retained coal dust, and to compare the behavior of two different Pennsylvania coals in the foregoing regards. The principal findings include: retention half-times for both coals of approximately 2 years following single, hour-long exposures; a vivid association of the retained coal dust with the pulmonic lymphatics; and a general validation of the retention model.

  3. Chronic treatment with the serotonin 2A/2C receptor antagonist SR 46349B enhances the retention and efficiency of rule-guided behavior in mice.

    PubMed

    Dougherty, John P; Oristaglio, Jeff

    2013-07-01

    Animal studies have established that drugs activating the serotonin 2A (5-HT2A) receptor can enhance learning and memory in a variety of classical and operant conditioning tasks. Unfortunately, long-term agonism typically results in receptor downregulation, which can negate such nootropic effects. Conversely, chronic antagonism can act to increase receptor density, an adaptation which, in principle, should enhance cognition in a manner similar to acute agonism. In this study, we questioned whether chronic treatment with the 5-HT2A receptor antagonist, SR 46349B, a drug known to increase 5-HT2A receptor density in vivo, would improve cognitive performance in normal mice. To address this question, we administered SR 46349B to mice for 4 days following initial training on a simple rule-based reward acquisition task. We subsequently tested their recall of this task and, finally, their ability to adapt to a reversal in reward contingency (reversal learning). For comparison, two additional groups were treated with the 5-HT2A/2C receptor agonist, DOI, which downregulates the 5-HT2A receptor. SR 46349B improved retention of the previously-learned task but did not affect reversal learning. Subjects treated with SR 46349B also completed trials faster and with greater motor efficiency than vehicle- or DOI-treated subjects. We hypothesize that long-term drug treatments resulting in 5-HT2A receptor up-regulation may be useful in enhancing recall of learned behaviors and, thus, may have potential for treating cognitive impairment associated with neurodegenerative disorders. PMID:23587729

  4. Managing retention.

    PubMed

    Carter, Tony

    2007-01-01

    To build this process it is necessary to consult customers for preferences, build familiarity and knowledge to build a relationship and conduct business in a customized fashion. The process takes every opportunity to build customer satisfaction with each customer contact. It is an important process to have, since customers today are more demanding, sophisticated, educated and comfortable speaking to the company as an equal (Belk, 2003). Customers have more customized expectations so they want to be reached as individuals (Raymond and Tanner, 1994). Also, a disproportionate search for new business is costly. The cost to cultivate new customers is more than maintaining existing customers (Cathcart, 1990). Other reasons that customer retention is necessary is because many unhappy customers will never buy again from a company that dissatisfied them and they will communicate their displeasure to other people. These dissatisfied customers may not even convey their displeasure but without saying anything just stop doing business with that company, which may keep them unaware for some time that there is any problem (Cathcart, 1990). PMID:18453139

  5. An Unexpected Observation Concerning the Effect of Anionic Additives on the Retention Behavior of Basic Drugs and Peptides in Reversed-Phase Liquid Chromatography

    PubMed Central

    Wang, Xiaoli; Carr, Peter W.

    2011-01-01

    Anionic species with ion pair forming ability are commonly used to enhance the retention and efficiency of basic analytes in RPLC separations. However, little is known about the interactions between organic mobile phase modifiers and such ion pairing anions. In this work, we measured the magnitude of the retention increase of basic drugs and peptides upon addition of strong inorganic ion pairing anions (e.g. perchlorate) as a function of the volume fraction of modifier in acidic water-acetonitrile mobile phases on two different stationary phases. We found that the increase in retention upon addition of various salts depended strongly on the eluent strength. In general, larger retention increases upon addition of the anion were observed at higher organic fractions. Regression of retention against the volume fraction of organic modifier indicated that the ion pair forming anions substantially decreased S values while only slightly changing ln k’w values. The decrease in S is the major cause of the retention increase of basic drugs and peptides when such anions are added to the mobile phase. PMID:17448482

  6. Classroom Management for Student Retention.

    ERIC Educational Resources Information Center

    Santa Rita, Emilio

    This guidebook recommends methods for teachers to use to improve teacher-student interaction in the classroom, as a means of increasing student retention. Chapter I introduces eight major systems of classroom management which teachers may use as their values and the classroom situation dictate: "Behavior Modification,""Reality Therapy,""Discipline…

  7. Retentivity, selectivity and thermodynamic behavior of polycyclic aromatic hydrocarbons on charge-transfer and hypercrosslinked stationary phases under conditions of normal phase high performance liquid chromatography.

    PubMed

    Jiang, Ping; Lucy, Charles A

    2016-03-11

    Charge-transfer and hypercrosslinked polystyrene phases offer retention and separation for polycyclic aromatic hydrocarbons (PAHs) and thus have potential for petroleum analysis. The size, shape and planarity selectivity for PAH standards on charge-transfer (DNAP column) and hypercrosslinked polystyrene (HC-Tol and 5HGN columns) phases are different under normal phase liquid chromatography (NPLC). The HC-Tol column behaves like a conventional NPLC column with low retention of PAHs. Retention of PAHs on the DNAP and 5HGN are strong and increases with the number of aromatic rings. The main retention mechanism is through π-π interactions and dipole-induced dipole interaction. Thermodynamics indicates that the retention mechanism of PAHs remains unchanged over the temperature range 20-60°C. In addition, on either DNAP or 5HGN column, both linear and bent PAHs are retained through the same mechanism. But DNAP possesses smaller π-π interaction and higher planarity selectivity than 5HGN for PAHs. This is suggestive that DNAP interacts with PAHs through a disordered phase arrangement, while 5HGN behaves as an ordered adsorption phase. PMID:26879454

  8. Local retention behaviors of epitaxial and polycrystalline PbMg1/3Nb2/3O3-PbTiO3 thin films by scanning force microscopy

    NASA Astrophysics Data System (ADS)

    Lee, J. H.; Choi, M. R.; Oh, Y. J.; Jo, W.

    2007-08-01

    The authors report the results of retention in epitaxial and polycrystalline PbMg1/3Nb2/3O3-PbTiO3 (PMN-PT) thin films on SrRuO3 (SRO) and Pt. The SRO electrodes were deposited by pulsed laser deposition and the PMN-PT thin films were coated by a sol-gel method. Local poling behaviors of the PMN-PT domains were investigated as a function of time in both single-poled and reverse-poled regions by scanning force microscopy. An extended exponential decay is observed in the PMN-PT/SRO heterostructures while a fluctuated relaxation is shown in the PMN-PT/Pt films, suggesting that crystal orientation and grain growth is critical to understand retention of relaxor ferroelectrics.

  9. Transport, retention, and long-term release behavior of ZnO nanoparticle aggregates in saturated quartz sand: Role of solution pH and biofilm coating.

    PubMed

    Han, Yosep; Hwang, Gukhwa; Kim, Donghyun; Bradford, Scott A; Lee, Byoungcheun; Eom, Igchun; Kim, Pil Je; Choi, Siyoung Q; Kim, Hyunjung

    2016-03-01

    The transport, retention, and long-term release of zinc oxide nanoparticle aggregates (denoted below as ZnO-NPs) were investigated in saturated, bare and biofilm (Pseudomonas putida) coated sand packed columns. Almost complete retention of ZnO-NPs occurred in bare and biofilm coated sand when the influent solution pH was 9 and the ionic strength (IS) was 0.1 or 10 mM NaCl, and the retention profiles were always hyper-exponential. Increasing the solution IS and biofilm coating produced enhanced retention of ZnO-NPs near the column inlet. The enhanced NPs retention at high IS was attributed to more favorable NP-silica and NP-NP interactions; this was consistent with the interaction energy calculations. Meanwhile, the greater NPs retention in the presence of biofilm was attributed to larger roughness heights which alter the mass transfer rate, the interaction energy profile, and lever arms associated with the torque balance; e.g., scanning electron and atomic force microscopy was used to determine roughness heights of 33.4 nm and 97.8 nm for bare sand and biofilm-coated sand, respectively. Interactions between NPs and extracellular polymeric substances may have also contributed to enhanced NP retention in biofilm-coated sand at low IS. The long-term release of retained ZnO-NPs was subsequently investigated by continuously injecting NP-free solution at pH 6, 9, or 10 and keeping the IS constant at 10 mM. The amount and rate of retained ZnO-NP removal was strongly dependent on the solution pH. Specifically, almost complete removal of retained ZnO-NPs was observed after 627 pore volumes when the solution pH was 6, whereas much less Zn was recovered when the eluting solution pH was buffered to pH = 9 and especially 10. This long-term removal was attributed to pH-dependent dissolution of retained ZnO-NPs because: (i) the solubility of ZnO-NPs increases with decreasing pH; and (ii) ZnO-NPs were not detected in the effluent. The presence of biofilm also decreased the

  10. Mechanisms of gas bubble retention

    SciTech Connect

    Gauglitz, P.A.; Mahoney, L.A.; Mendoza, D.P.; Miller, M.C.

    1994-09-01

    Retention and episodic release of flammable gases are critical safety concerns regarding double-shell tanks (DSTs) containing waste slurries. Previous investigations have concluded that gas bubbles are retained by the slurry that has settled at the bottom of the DST. However, the mechanisms responsible for the retention of these bubbles are not well understood. In addition, the presence of retained gas bubbles is expected to affect the physical properties of the sludge, but essentially no literature data are available to assess the effect of these bubbles. The rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles. The objectives of this study are to elucidate the mechanisms contributing to gas bubble retention and release from sludge such as is in Tank 241-SY-101, understand how the bubbles affect the physical properties of the sludge, develop correlations of these physical properties to include in computer models, and collect experimental data on the physical properties of simulated sludges with bubbles. This report presents a theory and experimental observations of bubble retention in simulated sludge and gives correlations and new data on the effect of gas bubbles on sludge yield strength.

  11. Scaling Laws for Reduced-Scale Tests of Pulse Jet Mixing Systems in Non-Newtonian Slurries: Gas Retention and Release Behavior

    SciTech Connect

    Stewart, Charles W.; Meyer, Perry A.; Kurath, Dean E.; Barnes, Steven M.

    2006-03-02

    The Waste Treatment Plant (WTP) under construction at the Hanford Site will use pulse jet mixer (PJM) technology for mixing and gas retention control applications in tanks expected to contain waste slurries exhibiting a non-Newtonian rheology. This paper presents the results of theoretical and experimental studies performed to establish the methodology to perform reduced-scale gas retention and release tests with PJM systems in non-Newtonian fluids with gas generation. The technical basis for scaled testing with unsteady jet mixing systems in gas-generating non-Newtonian fluids is presented in the form of a bubble migration model that accounts for the gas generation rate, the average bubble rise velocity, and the geometry of the vessel. Scaling laws developed from the model were validated with gas holdup and release tests conducted at three scales: large scale, 1/4 scale, and 1/9 scale. Experiments were conducted with two non-Newtonian simulants with in-situ gas generation by decomposition of hydrogen peroxide. The data were compared non-dimensionally, and the important scale laws were examined. From these results, scaling laws are developed which allow the design of mixing systems at a reduced scale.

  12. Towards a Dynamic DES model

    NASA Astrophysics Data System (ADS)

    Subbareddy, Pramod; Candler, Graham

    2009-11-01

    Hybrid RANS/LES methods are being increasingly used for turbulent flow simulations in complex geometries. Spalart's detached eddy simulation (DES) model is one of the more popular ones. We are interested in examining the behavior of the Spalart-Allmaras (S-A) Detached Eddy Simulation (DES) model in its ``LES mode.'' The role of the near-wall functions present in the equations is analyzed and an explicit analogy between the S-A and a one-equation LES model based on the sub-grid kinetic energy is presented. A dynamic version of the S-A DES model is proposed based on this connection. Validation studies and results from DES and LES applications will be presented and the effect of the proposed modification will be discussed.

  13. Measuring Graduate Student Retention.

    ERIC Educational Resources Information Center

    Isaac, Paul D.

    1993-01-01

    The conceptual and technical problems that need to be considered when studying graduate student retention and degree progress are examined, and practical suggestions for the institutional researcher are offered. Terms are defined, retention measures are explained, and different types of analysis are outlined. Ideas are given for database…

  14. Typewriting: Retention and Relearning.

    ERIC Educational Resources Information Center

    Hagman, Joseph D.

    Retention and relearning of straight-copy typewriting skill among thirty-eight administrative specialists, 71L Military Occupational Speciality, were examined after the no-practice retention interval between Advanced Individual Training (AIT) graduation and unit duty. Over this interval, average typing speed decreased and errors increased. As a…

  15. Des Moines.

    ERIC Educational Resources Information Center

    Gore, Deborah, Ed.

    1988-01-01

    This document, intended for elementary students, contains articles and activities designed to acquaint young people with the history of Des Moines, Iowa. The articles are short, and new or difficult words are highlighted and defined for young readers. "The Raccoon River Indian Agency" discusses the archeological exploration of the indian…

  16. Effects of Episodic Variations in Web-Based Avian Influenza Education: Influence of Fear and Humor on Perception, Comprehension, Retention and Behavior

    ERIC Educational Resources Information Center

    Kim, Paul; Sorcar, Piya; Um, Sujung; Chung, Heedoo; Lee, Young Sung

    2009-01-01

    In order to provide empirical evidence on the role of a web-based avian influenza (AI) education program for mass communication and also ultimately help young children learn and develop healthy behaviors against AI and all types of influenza, an education program with two episodic variations (i.e. fear and humor) has been developed and examined…

  17. The Effect of Voice Ambulatory Biofeedback on the Daily Performance and Retention of a Modified Vocal Motor Behavior in Participants with Normal Voices

    ERIC Educational Resources Information Center

    Van Stan, Jarrad H.; Mehta, Daryush D.; Hillman, Robert E.

    2015-01-01

    Purpose: Ambulatory biofeedback has potential to improve carryover of newly established vocal motor behaviors into daily life outside of the clinic and warrants systematic research that is lacking in the literature. This proof-of-concept study was designed to establish an empirical basis for future work in this area by formally assessing whether…

  18. Perceptions of the Impact of School Administrators on Teacher Retention

    ERIC Educational Resources Information Center

    Knight, Zsa Zsa L.

    2012-01-01

    This qualitative study investigated the behaviors of administrators and their impact on teacher retention. Teachers' perceptions were obtained in order to gain further understanding of the impact that administrators have on teachers' job satisfaction as well as of administrators' motivation to increase teacher retention. According…

  19. Teacher Beliefs regarding Grade Retention in an Urban Elementary School

    ERIC Educational Resources Information Center

    Gilmore-Hook, Toni

    2011-01-01

    The purpose of this study was to determine if exposure to a research-based presentation on grade retention, including the academic, socio-emotional and behavioral outcomes, would yield a change in teacher beliefs regarding retention as an intervention strategy. Teachers from a small urban school district were asked to complete a pre-survey, view a…

  20. Alternatives to Social Promotion and Retention

    ERIC Educational Resources Information Center

    Lynch, Matthew

    2013-01-01

    Studies indicate that retention negatively impacts students' behavior, attitude, and attendance, but it is still practiced in schools around the country. Social promotion undermines students' futures when they fail to develop critical study and job-related skills; however, it too is still practiced in many schools throughout the United…

  1. Drug Retention Times

    SciTech Connect

    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

  2. Drug Retention Times

    SciTech Connect

    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.

  3. [Chronic monstrous urine retention].

    PubMed

    Thomsen, Frederik Gustav; Holm, Mette Lind

    2015-01-26

    A 75-year-old male was diagnosed with renal mass at a computed tomography during an examination for extended abdominal girth. A large mesenterical cyst was also detected. The patient had infrequent voiding, which he had trained over many years as a taxi driver. A basic physical examination led to suspect urinary retention. His creatinine level was normal and he had no hydronephrosis. A renography showed equal function, but prolonged bilateral outflow. The volume extracted by urethral catheter passed 15 l. Absence of hydronephrosis and normal S-creatinine level has not been described in chronic urinary retention of this extent. Hydronephrosis is seen, but in much smaller volume of retention. Infrequent voiding is easily diagnosed. Urinary retention should be suspected when finding median cystic processes. PMID:25612956

  4. Retention in Tough Times.

    ERIC Educational Resources Information Center

    Kaye, Beverly; Jordan-Evans, Sharon

    2002-01-01

    Interviews with 25 global talent leaders discuss keeping good people and the challenges and emerging practices for retaining employees. Sidebars discuss retention tips and what keeps people on the job. (JOW)

  5. Foraging behavior of the mangrove sesarmid crab Neosarmatium trispinosum enhances food intake and nutrient retention in a low-quality food environment

    NASA Astrophysics Data System (ADS)

    Harada, Yota; Lee, S. Y.

    2016-06-01

    The large sesarmid crab Neosarmatium trispinosum has been reported to actively collect freshly fallen mangrove leaves and store them in its burrow where they are assumed to age prior to consumption. This leaf-catching behavior was hypothesized to improve the palatability and nutritional quality of leaves through leaching of feeding deterrent and microbial enrichment during storage. Earlier studies also hypothesized that N. trispinosum feeds on sediment or animal material to meet their N needs. A series of experiments was carried out to investigate the foraging behavior of N. trispinosum against these hypotheses. Study of foraging behavior using remotely operated cameras indicated that this crab spends the far majority of time (97.5 ± 2.5%, SD) underground and only a small percentage of time outside its burrow foraging (2.2 ± 2.3%). Collection of fresh mangrove litter was swift but no record of predation was evident over 31 h of video records. A field leaf tethering experiment showed that this crab started to consume the leaves immediately after collection rather than storing whole leaves, refuting the leaf-aging hypothesis. N. trispinosum also showed a preference for senescent yellow leaves over decaying brown leaves. This behavior may only aim to stock leaves (i.e. to ensure food availability) rather than conditioning them through decay (i.e. to improve food quality). Analysis of gut contents showed that vascular plant material was the dominant food item (83.3 ± 4.6%), followed by sediment (9.2 ± 4.6%) but no animal materials were recorded. N. trispinosum therefore relies minimally on animal food but are capable of removing 50% of the daily leaf litter production. Elemental C, N analysis shows that sediment inside the burrow is a sufficient potential food source (C/N = 13 to 15). While having a lower C/N ratio than fresh green or yellow leaves, the N content of sediment (∼0.1%) was significantly lower than those of mangrove leaves (0

  6. Foraging behavior of the mangrove sesarmid crab Neosarmatium trispinosum enhances food intake and nutrient retention in a low-quality food environment

    NASA Astrophysics Data System (ADS)

    Harada, Yota; Lee, S. Y.

    2016-06-01

    The large sesarmid crab Neosarmatium trispinosum has been reported to actively collect freshly fallen mangrove leaves and store them in its burrow where they are assumed to age prior to consumption. This leaf-catching behavior was hypothesized to improve the palatability and nutritional quality of leaves through leaching of feeding deterrent and microbial enrichment during storage. Earlier studies also hypothesized that N. trispinosum feeds on sediment or animal material to meet their N needs. A series of experiments was carried out to investigate the foraging behavior of N. trispinosum against these hypotheses. Study of foraging behavior using remotely operated cameras indicated that this crab spends the far majority of time (97.5 ± 2.5%, SD) underground and only a small percentage of time outside its burrow foraging (2.2 ± 2.3%). Collection of fresh mangrove litter was swift but no record of predation was evident over 31 h of video records. A field leaf tethering experiment showed that this crab started to consume the leaves immediately after collection rather than storing whole leaves, refuting the leaf-aging hypothesis. N. trispinosum also showed a preference for senescent yellow leaves over decaying brown leaves. This behavior may only aim to stock leaves (i.e. to ensure food availability) rather than conditioning them through decay (i.e. to improve food quality). Analysis of gut contents showed that vascular plant material was the dominant food item (83.3 ± 4.6%), followed by sediment (9.2 ± 4.6%) but no animal materials were recorded. N. trispinosum therefore relies minimally on animal food but are capable of removing 50% of the daily leaf litter production. Elemental C, N analysis shows that sediment inside the burrow is a sufficient potential food source (C/N = 13 to 15). While having a lower C/N ratio than fresh green or yellow leaves, the N content of sediment (∼0.1%) was significantly lower than those of mangrove leaves (0.3-0.9%), and may thus

  7. Fluence dependence of deuterium retention in oxidized SS-316

    NASA Astrophysics Data System (ADS)

    Oya, Yasuhisa; Suzuki, Sachiko; Matsuyama, Masao; Hayashi, Takumi; Yamanishi, Toshihiko; Asakura, Yamato; Okuno, Kenji

    2011-10-01

    The ion fluence dependence of deuterium retention in SS-316 during oxidation at a temperature of 673 K was studied to evaluate the dynamics of deuterium retention in the oxide layer of SS-316. The correlation between the chemical state of stainless steel and deuterium retention was evaluated using XPS and TDS. It was found that the major deuterium desorption temperatures were located at around 660 K and 935 K, which correspond to the desorption of deuterium trapped as hydroxide. The deuterium retention increased with increasing deuterium ion fluence, since the deuterium retention as hydroxide increased significantly. However, retention saturated at an ion fluence of ˜2.5 × 10 21 D + m -2. The XPS result showed that FeOOD was formed on the surface, although pure Fe also remained in the oxide layer. These facts indicate the nature of the oxide layer have a key role in deuterium trapping behavior.

  8. Grade Retention and Its Association with School Misconduct in Adolescence: A Multilevel Approach

    ERIC Educational Resources Information Center

    Demanet, Jannick; Van Houtte, Mieke

    2013-01-01

    Few studies with respect to grade retention and school-disruptive behavior have focused on adolescence. Moreover, previous retention research has ignored multilevel issues. This study aims to fill these research lacunae by addressing the role of grade retention in adolescent students' school misconduct. Furthermore, we explore the role of the…

  9. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1994-04-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rests, interocclusal clearance and cingulum stops is equally important. Including more teeth in the design does not necessarily lead to an improved retention. Besides the material and technical aspects, the whole clinical procedure needs much attention. The retention does not depend on one single factor, but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 80% can be obtained. PMID:11830965

  10. Surface retention capacity calculation

    NASA Astrophysics Data System (ADS)

    David, Vaclav; Dostal, Tomas

    2010-05-01

    Flood wave transformation in the floodplain is the phenomenon which is researched within interdisciplinary project NIVA - Water Retention in Floodplains and Possibilities of Retention Capacity Increase. The project focuses on broad range of floodplain ecosystem services and mitigation of flooding is one of them. Despite main influence on flood wave transformation is due to flow retardation, retention in surface depressions within floodplain has been analyzed to get better overview of whole transformation process. Detail digital relief model (DRM) has been used for given purposes to be able to analyze terrain depressions volumes. The model was developed with use of stereophotogrammetric evaluation of airborne images with high resolution of 10 cm. It was essential for purposes of presented analysis not to apply pit removal routines which are often used for generation of DRM for hydrological modelling purposes. First, the methodology of analysis was prepared and tested on artificial surface. This surface was created using random raster generation, filtration and resampling with final resolution of 1000 x 1000 units and height of maximum 10 units above datum. The methodology itself is based on analysis of areas inundated by water at different elevation levels. Volume is than calculated for each depression using extraction of terrain elevations under corresponding water level. The method was then applied on the area of Lužnice River floodplain section to assess retention capacity of real floodplain. The floodplain had to be cut into sections perpendicular to main river orientation for analyses as the method was tested for square shaped area without any significant inclination. Results obtained by mentioned analysis are presented in this paper. Acknowledgement Presented research was accomplished within national project NIVA - Water Retention in Floodplains and Possibilities of Retention Capacity Increase, nr. QH82078. The project is funded by Ministry of Agriculture of

  11. Recruitment, Retention, Attrition Project.

    ERIC Educational Resources Information Center

    Horvath, Ronald J., Ed.

    Based on a series of faculty workshops conducted at Jefferson Community College (KY) in 1978 and 1980, this handbook outlines 95 practical suggestions for increasing student retention rates. After introductory material describing these workshops, the first 22 suggestions recommend ways to foster positive student/teacher interaction. Methods are…

  12. Principals Retention. Research Brief

    ERIC Educational Resources Information Center

    Muir, Mike

    2005-01-01

    Many districts are struggling with the problem of administrator retention. Hoffman (2004) identifies some of the reasons for this: (1) Increased accountability expectations; (2) Diminished or static levels of resources to support reform efforts; (3) Greater administrator vulnerability to sanctions; (4) The complex demands of government and the…

  13. Tritium retention in TFTR

    SciTech Connect

    Dylla, H.F.; Wilson, K.L.

    1988-04-01

    This report discusses the materials physics related to D-T operation in TFTR. Research activities are described pertaining to basic studies of hydrogenic retention in graphite, hydrogen recycling phenomena, first-wall and limiter conditioning, surface analysis of TFTR first-wall components, and estimates of the tritium inventory.

  14. Retention and Persistence Data.

    ERIC Educational Resources Information Center

    Sanford, Timothy R.

    Two studies are combined with an introductory section: one is "Persistence to Graduation for Freshmen Entering the University of North Carolina at Chapel Hill, 1967-75," by Timothy Sanford, and the second is "Freshman, Transfer, Professional, Masters, and Doctoral Student Retention at the University of North Carolina at Chapel Hill," by Paul D.…

  15. Improving College Freshman Retention

    ERIC Educational Resources Information Center

    Yu, Winnie Y.

    2012-01-01

    In recent years, access to higher education was greatly improved through public funding. This improvement is not matched by a similar increase in graduation rate. The purpose of this study is to examine what postsecondary institutions can do to improve college freshman retention. The conceptual framework was based on research on college student…

  16. Secrets of Retention

    ERIC Educational Resources Information Center

    Poliniak, Susan

    2012-01-01

    Recruiting students is one thing, but keeping them in a chorus, orchestra, or band is another. Although a music director has no control over some variables, there is much that can be done to help students to stay. Several experts share their advice on retention. One expert said a teacher's own attitude and classroom strategies may be two of the…

  17. [Retention of adhesive bridges].

    PubMed

    Raes, F; De Boever, J

    1990-01-01

    Since the development of adhesive bridges in the early seventies, the retention and therefore the durability of these bridges has been tremendously improved. To ensure an adequate retention over a number of years different factors have to be considered. Conditioning of the non-precious metal by silanisation, careful acid etching of the enamel and the use of the appropriate composite resin (Panavia Ex) are of prime importance. Furthermore, the meticulous preparation with enough interproximal embrace, occlusal rets, interocclusal clearance of 0.4 mm and cingulum stops is equally important. Care should be taken not to remove all the enamel in the cervical region in preparing a mini chamfer. Including more teeth in the design does not necessarily lead to an improved retention. Teeth with a different mobility should not be included in the same bridge. Besides the material and technical aspects, the whole clinical procedure needs much attention. Only an exact impression, a precise model and a reliable casting technique will provide a metal frame with an optimal marginal adaptation and a close fit. The retention does not depend on one single factor but on the precision of all the necessary clinical steps and on a well-defined selection of the material. In this way a five-year survival rate of close to 90% can be obtained. PMID:2077574

  18. Mobile Learning and Student Retention

    ERIC Educational Resources Information Center

    Fozdar, Bharat Inder; Kumar, Lalita S.

    2007-01-01

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

  19. Behaviorism

    ERIC Educational Resources Information Center

    Moore, J.

    2011-01-01

    Early forms of psychology assumed that mental life was the appropriate subject matter for psychology, and introspection was an appropriate method to engage that subject matter. In 1913, John B. Watson proposed an alternative: classical S-R behaviorism. According to Watson, behavior was a subject matter in its own right, to be studied by the…

  20. Theoretical Models and QSRR in Retention Modeling of Eight Aminopyridines.

    PubMed

    Tumpa, Anja; Kalinić, Marko; Jovanović, Predrag; Erić, Slavica; Rakić, Tijana; Jančić-Stojanović, Biljana; Medenica, Mirjana

    2016-03-01

    In this article, retention modeling of eight aminopyridines (synthesized and characterized at the Faculty of Pharmacy) in reversed-phase high performance liquid chromatography (RP-HPLC) was performed. No data related to their retention in the RP-HPLC system were found. Knowing that, it was recognized as very important to describe their retention behavior. The influences of pH of the mobile phase and the organic modifier content on the retention factors were investigated. Two theoretical models for the dependence of retention factor of organic modifier content were tested. Then, the most reliable and accurate prediction of log k was created, testing multiple linear regression model-quantitative structure-retention relationships (MLR-QSRR) and support vector regression machine-quantitative structure-retention relationships (SVM-QSRR). Initially, 400 descriptors were calculated, but four of them (POM, log D, M-SZX/RZX and m-RPCG) were included in the models. SVM-QSRR performed significantly better than the MLR model. Apart from aminopyridines, four structurally similar substances (indapamide, gliclazide, sulfamethoxazole and furosemide) were followed in the same chromatographic system. They were used as external validation set for the QSRR model (it performed well within its applicability domain, which was defined using a bounding box approach). After having described retention of eight aminopyridines with both theoretical and QSRR models, further investigations in this field can be conducted. PMID:26590237

  1. Effect of Grade Retention in First Grade on Psychosocial Outcomes

    ERIC Educational Resources Information Center

    Wu, Wei; West, Stephen G.; Hughes, Jan N.

    2010-01-01

    In a 4-year longitudinal study, the authors investigated effects of retention in first grade on children's externalizing and internalizing behaviors; social acceptance; and behavioral, cognitive, and affective engagement. From a large multiethnic sample (n = 784) of children below the median on literacy at school entrance, 124 retained children…

  2. Retention in medication-assisted treatment for opiate dependence: A systematic review.

    PubMed

    Timko, Christine; Schultz, Nicole R; Cucciare, Michael A; Vittorio, Lisa; Garrison-Diehn, Christina

    2016-01-01

    Retention in medication-assisted treatment among opiate-dependent patients is associated with better outcomes. This systematic review (55 articles, 2010-2014) found wide variability in retention rates (i.e., 19%-94% at 3-month, 46%-92% at 4-month, 3%-88% at 6-month, and 37%-91% at 12-month follow-ups in randomized controlled trials), and identified medication and behavioral therapy factors associated with retention. As expected, patients who received naltrexone or buprenorphine had better retention rates than patients who received a placebo or no medication. Consistent with prior research, methadone was associated with better retention than buprenorphine/naloxone. And, heroin-assisted treatment was associated with better retention than methadone among treatment-refractory patients. Only a single study examined retention in medication-assisted treatment for longer than 1 year, and studies of behavioral therapies may have lacked statistical power; thus, studies with longer-term follow-ups and larger samples are needed. Contingency management showed promise to increase retention, but other behavioral therapies to increase retention, such as supervision of medication consumption, or additional counseling, education, or support, failed to find differences between intervention and control conditions. Promising behavioral therapies to increase retention have yet to be identified. PMID:26467975

  3. Selenide retention by mackinawite.

    PubMed

    Finck, N; Dardenne, K; Bosbach, D; Geckeis, H

    2012-09-18

    The isotope (79)Se may be of great concern with regard to the safe disposal of nuclear wastes in deep geological repositories due to its long half-life and potential mobility in the geosphere. The Se mobility is controlled by the oxidation state: the oxidized species (Se(IV)) and (Se(VI)) are highly mobile, whereas the reduced species (Se(0) and Se(-II)) form low soluble solids. The mobility of this trace pollutant can be greatly reduced by interacting with the various barriers of the repository. Numerous studies report on the oxidized species retention by mineral phases, but only very scarce studies report on the selenide (Se(-II)) retention. In the present study, the selenide retention by coprecipitation with and by adsorption on mackinawite (FeS) was investigated. XRD and SEM analyses of the samples reveal no significant influence of Se on the mackinawite precipitate morphology and structure. Samples from coprecipitation and from adsorption are characterized at the molecular scale by a multi-edge X-ray absorption spectroscopy (XAS) investigation. In the coprecipitation experiment, all elements (S, Fe, and Se) are in a low ionic oxidation state and the EXAFS data strongly point to selenium located in a mackinawite-like sulfide environment. By contacting selenide ions with FeS in suspension, part of Se is located in an environment similar to that found in the coprecipitation experiment. The explanation is a dynamical dissolution-recrystallization mechanism of the highly reactive mackinawite. This is the first experimental study to report on selenide incorporation in iron monosulfide by a multi-edge XAS approach. PMID:22900520

  4. Floating nut retention system

    NASA Technical Reports Server (NTRS)

    Charles, J. F.; Theakston, H. A. (Inventor)

    1980-01-01

    A floating nut retention system includes a nut with a central aperture. An inner retainer plate has an opening which is fixedly aligned with the nut aperture. An outer retainer member is formed of a base plate having an opening and a surface adjacent to a surface of the inner retainer plate. The outer retainer member includes a securing mechanism for retaining the inner retainer plate adjacent to the outer retainer member. The securing mechanism enables the inner retainer plate to float with respect to the outer retainer number, while simultaneously forming a bearing surface for inner retainer plate.

  5. Phenotypic behavior of caveolin-3 mutations that cause autosomal dominant limb girdle muscular dystrophy (LGMD-1C). Retention of LGMD-1C caveolin-3 mutants within the golgi complex.

    PubMed

    Galbiati, F; Volonte, D; Minetti, C; Chu, J B; Lisanti, M P

    1999-09-01

    Caveolin-3, a muscle-specific caveolin-related protein, is the principal structural protein of caveolae membrane domains in striated muscle cell types (cardiac and skeletal). Autosomal dominant limb girdle muscular dystrophy (LGMD-1C) in humans is due to mutations within the caveolin-3 gene: (i) a 9-base pair microdeletion that removes three amino acids within the caveolin scaffolding domain (DeltaTFT) or (ii) a missense mutation within the membrane spanning domain (P --> L). The molecular mechanisms by which these two mutations cause muscular dystrophy remain unknown. Here, we investigate the phenotypic behavior of these caveolin-3 mutations using heterologous expression. Wild type caveolin-3 or caveolin-3 mutants were transiently expressed in NIH 3T3 cells. LGMD-1C mutants of caveolin-3 (DeltaTFT or P --> L) were primarily retained at the level of a perinuclear compartment that we identified as the Golgi complex in double-labeling experiments, while wild type caveolin-3 was efficiently targeted to the plasma membrane. In accordance with these observations, caveolin-3 mutants formed oligomers of a much larger size than wild type caveolin-3 and were excluded from caveolae-enriched membrane fractions as seen by sucrose density gradient centrifugation. In addition, these caveolin-3 mutants were expressed at significantly lower levels and had a dramatically shortened half-life of approximately 45-60 min. However, caveolin-3 mutants were palmitoylated to the same extent as wild type caveolin-3, indicating that targeting to the plasma membrane is not required for palmitoylation of caveolin-3. In conclusion, we show that LGMD-1C mutations lead to formation of unstable high molecular mass aggregates of caveolin-3 that are retained within the Golgi complex and are not targeted to the plasma membrane. Consistent with its autosomal dominant form of genetic transmission, we demonstrate that LGMD-1C mutants of caveolin-3 behave in a dominant-negative fashion, causing the

  6. Mechanisms of deterioration of nutrients. [retention of flavor during freeze drying

    NASA Technical Reports Server (NTRS)

    Karel, M.; Flink, J. M.

    1975-01-01

    The retention of flavor during freeze drying was studied with model systems. Mechanisms by which flavor retention phenomena is explained were developed and process conditions specified so that flavor retention is optimized. The literature is reviewed and results of studies of the flavor retention behavior of a number of real food products, including both liquid and solid foods are evaluated. Process parameters predicted by the mechanisms to be of greatest significance are freezing rate, initial solids content, and conditions which result in maintenance of sample structure. Flavor quality for the real food showed the same behavior relative to process conditions as predicted by the mechanisms based on model system studies.

  7. Molten core retention assembly

    DOEpatents

    Lampe, Robert F.

    1976-06-22

    Molten fuel produced in a core overheating accident is caught by a molten core retention assembly consisting of a horizontal baffle plate having a plurality of openings therein, heat exchange tubes having flow holes near the top thereof mounted in the openings, and a cylindrical, imperforate baffle attached to the plate and surrounding the tubes. The baffle assembly is supported from the core support plate of the reactor by a plurality of hanger rods which are welded to radial beams passing under the baffle plate and intermittently welded thereto. Preferably the upper end of the cylindrical baffle terminates in an outwardly facing lip to which are welded a plurality of bearings having slots therein adapted to accept the hanger rods.

  8. Retention through redemption.

    PubMed

    Abrashoff, D M

    2001-02-01

    Corporate America and the U.S. Navy share one big problem: employee retention. Today's knowledge workers hop from start-up to start-up. And 40% of the navy's new recruits leave the service before their four-year tours of duty are up. D. Michael Abrashoff came face to face with the navy's retention problem when he took command of the USS Benfold. Before he became captain, sailors couldn't get away from the ship fast enough. Today the vessel is the pride of the Pacific fleet, and sailors from other ships are clamoring to join its crew. In this firsthand account, Abrashoff explains how he got the ship and its crew back on course by breaking bad habits--personal and professional ones--and jettisoning old attitudes. During his 21 months aboard the Benfold, Abrashoff came to realize that in today's technology-intensive U.S. Navy, the traditional command-and-control style wouldn't work. And it hadn't--the Benfold's 310 sailors had cheered derisively when Abrashoff's predecessor had left the ship. So he defied 225 years of navy tradition in his quest to engage the sailors in their work, increase their performance, and keep them around for their entire tours of duty. He retained his crew by redeeming them--showing them how to be not just better sailors but better people, too. That meant breaking them down when they were at their worst and then building them up to reach their best. It also meant personal redemption for Abrashoff; he resolved to really listen to what his sailors were saying. The result? Cost-saving ideas for the entire navy and surging confidence and commitment among crew members. PMID:11213688

  9. Toward a Record Retention Policy

    ERIC Educational Resources Information Center

    Vaughan, Jason

    2007-01-01

    An academic library working group was charged in 2005 to create a records retention schedule and policy applicable to records containing personally identifiable information of library patrons. This group conducted a survey and extensive research, culminating in an adopted library records retention schedule and policy implemented in 2006.

  10. Retention in Grade: Lethal Lessons?

    ERIC Educational Resources Information Center

    Sherwood, Charles

    Despite a growing trend toward retention in grade of low-achieving students and apparent public support for the practice, many educators and psychologists disagree with the perception that flunking is an appropriate response to poor academic performance. Research reported in the past two decades indicates that grade-level retention produces little…

  11. Teacher Retention in Catholic Schools

    ERIC Educational Resources Information Center

    Przygocki, Walter F.

    2004-01-01

    Teacher attrition is a concern in all educational sectors but is of special importance to Catholic schools because of the salary disparity between public and Catholic schools. This review examines the research on teacher retention in general with a view to understanding how this knowledge might inform teacher recruitment and retention strategies…

  12. SULFUR RETENTION IN COAL ASH

    EPA Science Inventory

    The report gives results of an analytical study to assess the potential for sulfur retention in various types of coal-fired boilers. Results of a field test of 10 industrial coal-fired boilers were used to evaluate the impact on sulfur retention of the operating variables (load a...

  13. Effect of Grade Retention in First Grade on Psychosocial Outcomes

    PubMed Central

    Wu, Wei; West, Stephen G.; Hughes, Jan N.

    2010-01-01

    In a 4-year longitudinal study, the authors investigated effects of retention in first grade on children’s externalizing and internalizing behaviors; social acceptance; and behavioral, cognitive, and affective engagement. From a large multiethnic sample (n = 784) of children below the median on literacy at school entrance, 124 retained children were matched with 251 promoted children on the basis of propensity scores (probability of being retained in first grade estimated from 72 baseline variables). Relative to promoted children, retained children were found to benefit from retention in both the short and longer terms with respect to decreased teacher-rated hyperactivity, decreased peer-rated sadness and withdrawal, and increased teacher-rated behavioral engagement. Retained children had a short-term increase in mean peer-rated liking and school belongingness relative to promoted children, but this advantage showed a substantial decrease in the longer term. Retention had a positive short-term effect on children’s perceived school belonging and a positive longer term effect on perceived academic self-efficacy. Retention may bestow advantages in the short-term, but longer term detrimental effects on social acceptance may lead to the documented longer term negative effects of retention. PMID:20448829

  14. The Effects of a Suggestive Learning Climate, Synchronized Breathing and Music on the Learning and Retention of Spanish Words

    ERIC Educational Resources Information Center

    Benitez-Bordon, R.; Schuster, Donald H.

    1976-01-01

    This study found that the three variables, suggestion, synchronized music and breathing, had a large positive effect on the learning and retention of 50 Spanish words. Available from: Society for Suggestive-Accelerative Learning and Teaching, 2740 Richmond Avenue, Des Moines, Iowa 50319. (CFM)

  15. Payload retention device

    NASA Technical Reports Server (NTRS)

    Monford, Leo G., Jr. (Inventor)

    1992-01-01

    A payload retention device for grappling and retaining a payload in docked position on a supporting structure in the cargo bay of a space vehicle is presented. The device comprises a two-fault tolerant electromagnetic grappling system comprising electromagnets for attracting and grappling a grapple strike plate affixed to the payload when in proximity thereto and an electromechanical latching assembly comprising a pair of independent latching subassemblies. Each subassembly comprises a set of latching pawls which are driven into latching and unlatching positions relative to a grappled payload by a pair of gearmotors, each equipped with a ratchet clutch drive mechanism which is two-fault tolerant with respect to latching such that only one gearmotor of the four needs to be operational to effect a latch of the payload but is single fault tolerant with respect to release of a latched payload. Sensors are included for automatically sensing the magnetic grappling of a payload and for automatically de-energizing the gearmotors of the latching subassemblies when a latch condition is achieved.

  16. Data Retention and Anonymity Services

    NASA Astrophysics Data System (ADS)

    Berthold, Stefan; Böhme, Rainer; Köpsell, Stefan

    The recently introduced legislation on data retention to aid prosecuting cyber-related crime in Europe also affects the achievable security of systems for anonymous communication on the Internet. We argue that data retention requires a review of existing security evaluations against a new class of realistic adversary models. In particular, we present theoretical results and first empirical evidence for intersection attacks by law enforcement authorities. The reference architecture for our study is the anonymity service AN.ON, from which we also collect empirical data. Our adversary model reflects an interpretation of the current implementation of the EC Directive on Data Retention in Germany.

  17. The Impact of Principal Leadership on Working Conditions and Teacher Retention in North Carolina Middle Schools

    ERIC Educational Resources Information Center

    Tomon, Catherine

    2009-01-01

    Research indicates that administrative leadership is the most important factor in determining the climate of a school, and there are specific leadership attributes such as improving working conditions that promote retention. This study seeks to identify leadership behaviors that positively affect quality teacher retention among two particular…

  18. Early-Grade Retention and Children's Reading and Math Learning in Elementary Years

    ERIC Educational Resources Information Center

    Hong, Guanglei; Yu, Bing

    2007-01-01

    Many schools have adopted early-grade retention as an intervention strategy for children displaying academic or behavioral problems. Previous analyses of the Early Childhood Longitudinal Study Kindergarten Cohort data have found evidence of negative effects of kindergarten retention on academic learning during the repeated year. Will kindergarten…

  19. Models of retention of adamantylamidrazones in reversed-phase high-performance liquid chromatography

    NASA Astrophysics Data System (ADS)

    Prokopov, S. V.; Kurbatova, S. V.

    2011-05-01

    Rules governing the chromatographic behavior of some amidrazones of the adamantane series were studied under the conditions of reversed-phase high-performance liquid chromatography. The characteristics of the retention of sorbates in elution by aqueous-acetonitrile phases with various compositions were calculated. Correlations between the structure and physicochemical characteristics of sorbate molecules and their retention were studied.

  20. A Job Retention Model for Individuals with Mental Retardation

    ERIC Educational Resources Information Center

    Fornes, Sandra

    2006-01-01

    This structured literature review examines the literature and addresses issues of job retention for adult workers with moderate to mild mental retardation (MR), investigating the relationships between work-related social behaviors, self-determination, person-job congruency of individuals with MR, and their job performance and job satisfaction with…

  1. Skill Retention and Relearning--A Proposed Cyclical Model.

    ERIC Educational Resources Information Center

    Ginzburg, S.; Dar-El, E. M.

    2000-01-01

    The relationship between relearning and retention was examined during refresher training for 53 Israeli soldiers operating an electronic system. The longer the training interval, the lower the operator's performance level. Partial simulation was suitable for retraining in complex tasks. A cyclical behavior model of learning, forgetting, and…

  2. Retention, Persistence, and Enrollment Management: An Exploration of Organizational Models

    ERIC Educational Resources Information Center

    Bartlett, Stacy A.

    2013-01-01

    Low student retention and persistence continues to be a major problem within American higher education (Elkins, Braxton, & James, 2000; Kalsbeek & Hossler, 2010; Kezar, 2004; Tinto, 2006-2007). Less is known about the institutional organizational behavior influence on student persistence (Berger, 2001-2002); and while enrollment management…

  3. Improving Retention through Intensive Practice in College Survival Skills.

    ERIC Educational Resources Information Center

    McIntire, Roger W.; And Others

    1992-01-01

    Examined effectiveness of General Education 100 (GNED 100), behaviorally oriented course addressing nonacademic/academic factors affecting student retention. Compared to performance predicted by university's admissions formula, performance of 407 GNED 100 students exceeded predicted norms by as much as 1 grade point. Differences related positively…

  4. Professional Development and Mentoring in Support of Teacher Retention

    ERIC Educational Resources Information Center

    Rodgers, Christopher; Skelton, Jillian

    2014-01-01

    The authors' discussion will describe how teacher retention is in jeopardy. Many novice teachers are ill-prepared to handle the rigorous school days and challenging students academically and behaviorally (Stansbury & Zimmerman, 2002). Novice teachers need guidance and support to ease tensions and stress levels which arise during teaching…

  5. Family, Personality, and Social Risk Factors Impacting the Retention Rates of First-Year Hispanic and Anglo College Students.

    ERIC Educational Resources Information Center

    Pidcock, Boyd W.; Fischer, Judith L.; Munsch, Joyce

    2001-01-01

    Investigates potential ethnic differences between Hispanic and Angelo-American college freshman that may increase their risk of drinking and problem behaviors in an attempt to understand Hispanic's low college retention rate. Findings identified key family, social, personality, and problem behaviors associated with students' retention rates and…

  6. EA Shuttle Document Retention Effort

    NASA Technical Reports Server (NTRS)

    Wagner, Howard A.

    2010-01-01

    This slide presentation reviews the effort of code EA at Johnson Space Center (JSC) to identify and acquire databases and documents from the space shuttle program that are adjudged important for retention after the retirement of the space shuttle.

  7. Successful recruitment and retention of Latino study participants.

    PubMed

    Reidy, Mary Clare; Orpinas, Pamela; Davis, Marsha

    2012-11-01

    A high prevalence of risk behaviors among the rapidly growing Latino youth population in the United States adds urgency to the need to identify effective recruitment and retention strategies for research studies and prevention programs. The objectives of this study are to (a) describe the culturally responsive recruitment and retention strategies used in the Familias Fuertes-Georgia program and (b) discuss the evaluation of the relative importance of these strategies. Familias Fuertes (i.e., Strong Families) is a community-based, primary prevention program for families in Latin America with children between the ages of 10 and 14 years. The main program goal is to reduce high-risk behaviors among adolescents by strengthening family relationships and promoting self-regulation and positive conflict resolution strategies. A pilot feasibility study was conducted to determine the appropriateness of the Familias Fuertes program for Latino families living in the United States. To promote participation, 15 culturally responsive recruitment and retention strategies were developed using a three-step process. These strategies contributed to the successful recruitment and retention of Familias Fuertes-Georgia study participants. Participating parents, the community liaison, and the community leader evaluated the relative importance of the 15 culturally responsive recruitment and retention strategies. Three of the strategies emerged as more important than others: face-to-face recruitment by the community liaison; bilingual, bicultural, and experienced facilitators; and free on-site child care. Further research is needed to develop strategies promoting the participation of male caregivers/fathers. PMID:21540195

  8. Turnover: strategies for staff retention.

    PubMed

    SnowAntle, S

    1990-01-01

    This discussion has focused on a number of areas where organizations may find opportunities for more effectively managing employee retention. Given the multitude of causes and consequences, there is no one quick fix. Effective management of employee retention requires assessment of the entire human resources process, that is, recruitment, selection, job design, compensation, supervision, work conditions, etc. Regular and systematic diagnosis of turnover and implementation of multiple strategies and evaluation are needed (Mobley, 1982). PMID:10106673

  9. Retention Rate by Ethnicity. Information Capsule.

    ERIC Educational Resources Information Center

    Baldwin, Anne

    This document discusses retention rate based on ethnicity for Miami-Dade Community College (M-DCC) for December 2002. The study found that the 2001 Fall-Spring retention rates increased among all ethnic groups. The total college retention rate rose by 2.7 percentage points to 75.2%. Among individual groups, the highest retention rate of 76.9% was…

  10. Des ballons pour demain

    NASA Astrophysics Data System (ADS)

    Régipa, R.

    A partir d'une théorie sur la détermination des formes et des contraintes globales d'un ballon de révolution, ou s'en rapprochant, une nouvelle famille de ballons a été définie. Les ballons actuels, dits de ``forme naturelle'', sont calculés en général pour une tension circonférencielle nulle. Ainsi, pour une mission donnée, la tension longitudinale et la forme de l'enveloppe sont strictement imposées. Les ballons de la nouvelle génération sont globalement cylindriques et leurs pôles sont réunis par un câble axial, chargé de transmettre une partie des efforts depuis le crochet (pôle inférieur), directement au pôle supérieur. De plus, la zone latérale cylindrique est soumise à un faible champ de tensions circonférencielles. Ainsi, deux paramètres permettent de faire évoluer la distribution des tensions et la forme de l'enveloppe: - la tension du câble de liaison entre pôles (ou la longueur de ce câble) - la tension circonférencielle moyenne désirée (ou le rayon du ballon). On peut donc calculer et réaliser: - soit des ballons de forme adaptée, comme les ballons à fond plat pour le bon fonctionnement des montgolfières infrarouge (projet MIR); - soit des ballons optimisés pour une bonne répartition des contraintes et une meilleure utilisation des matériaux d'enveloppe, pour l'ensemble des programmes stratosphériques. Il s'ensuit une économie sensible des coûts de fabrication, une fiabilité accrue du fonctionnement de ces ballons et une rendement opérationnel bien supérieur, permettant entre autres, d'envisager des vols à très haute altitude en matériaux très légers.

  11. Amputation des quatre membres

    PubMed Central

    Feruzi, Maruis Kitembo; Milindi, Cédrick Sangwa; Zabibu, Mireille Kakinga; Mulefu, Jules Panda; Katombe, Francois Tshilombo

    2014-01-01

    Les auteurs présentent les cas d'amputation des quatre membres réalisée chez trois patients différents. Ce sont des amputations réalisées pour chaque patient au cours d'une seule hospitalisation et en un seul temps opératoire. Deux patients pour gangrène sèche infectée et un pour amputation traumatique des quatre membres. L'amputation d'urgence a été pratiquée en premier temps suivie de remodelage des moignons d'amputation en second temps. L’évolution de tous les patients a été bonne. PMID:25469177

  12. Prediction of gas chromatographic retention data for hydrocarbons from naphthas

    SciTech Connect

    Woloszyn, T.F.; Jurs, P.C. )

    1993-03-01

    Regression equations that model the gas chromatographic retention behavior of hydrocarbons found in complex petrochemical mixtures were developed for two different stationary phases, SE-30 and Carbowax 20M. The models had relative standard errors in the range 1--2%. This quantitative structure-retention relationship (QSRR) study focused on a relatively heterogeneous data set and resulted in the generation of several statistical models that related Kovats' retention index with descriptors that encode molecular structure. Also investigated was the addition of boiling point as a physicochemical descriptor. These models bore a significant improvement over the models containing only structural descriptors, with R values of 0.996. 27 refs., 4 figs., 8 tabs.

  13. Retention of hydrogen in graphite

    SciTech Connect

    Langley, R.A.

    1986-10-01

    The retention of hydrogen in POCO AXF-5Q graphite has been measured at room temperature as a function of fluence and flux for H/sub 2//sup +/ ions at energies from 250 to 500 eV provided by a glow discharge. More than 2 x 10/sup 18/ H/cm/sup 2/ has been retained, and no indication of saturation has been observed to a fluence of 5 x 10/sup 19/ H/cm/sup 2/. In this experiment, retention was found to increase linearly with fluence for constant flux. A flux dependence was observed; that is, the retention rate was observed to decrease monotonically as the flux increased. A change-over experiment, deuterium to hydrogen, was conducted; the results show that significant change-over occurs (i.e., about 30% change-over for a fluence of 5 x 10/sup 17/ D/cm/sup 2/).

  14. Influence of hydrologic loading rate on phosphorus retention and ecosystem productivity in created wetlands. Final report

    SciTech Connect

    Mitsch, W.J.; Cronk, J.K.

    1995-01-01

    Four 2- to 3-ha constructed freshwater riparian wetlands in Lake County, Illinois, were subjected to two hydrologic regimes of pumped river water to simulate nonpoint source pollution. The experimental wetlands at the Des Plaines River Wetland Demonstration Project were designed to develop and test wetland design principles, construction methods, and management programs needed to create and maintain wetlands for the purposes of water quality management, flood control, and fish and wildlife habitat. High-flow wetlands (HFW) with short retention times received 34 to 38 cm of river water per week, and low-flow wetlands (LFW) with high retention times received 10 to 15 cm per week. This report summarizes research results for phosphorus dynamics and retention, macrophyte development, periphyton productivity, and overall water column metabolism through 1992. All of these functions were hypothesized to be related to hydrologic conditions.

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

    PubMed

    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

  16. Implicit Memory: Retention without Remembering.

    ERIC Educational Resources Information Center

    Roediger, Henry L., III

    1990-01-01

    Reviews recent research on retention that is demonstrated without conscious recollection, such as the ability to tie shoelaces or drive a car. Suggests that future research in this field may have implications for such educational issues as the transfer of training and the carryover of abstract classroom learning to problems in other contexts. (EVL)

  17. JCC Recruitment, Retention, Attrition Project.

    ERIC Educational Resources Information Center

    Horvath, Ronald J.

    In an effort to reduce the class attrition rate of 40% at Jefferson Community College (JCC), and to investigate the entire process of recruitment, retention, and attrition (RRA), a series of four faculty workshops were held. The plan was to look at the RRA process from the student's point of view in terms of four phases: (1) the pre-enrollment…

  18. Maslow's Hierarchy and Student Retention.

    ERIC Educational Resources Information Center

    Brookman, David M.

    1989-01-01

    Abraham Maslow's hierarchy of needs offers perspective on student motivation and a rationale for college retention programing. Student affairs and faculty interventions addressing student safety needs and engaging students' sense of purpose reinforce persistence. A mentor program is a possible cooperative effort between student personnel and…

  19. Strategies for improving employee retention.

    PubMed

    Verlander, Edward G; Evans, Martin R

    2007-01-01

    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. PMID:17394785

  20. Meeting Individual Needs Fosters Retention.

    ERIC Educational Resources Information Center

    Artman, Johanne I.; Gore, Robert C.

    A 1991 study of non-returning students at Del Mar College (DMC), in Corpus Christi, Texas, revealed that only 37.9% of these students were actual dropouts (i.e., had failed to accomplish their educational goals, and had no plans to take up further study). Retention studies conducted in Texas between 1985 and 1989 have shown that DMC has…

  1. Exploring General Education Development Retention

    ERIC Educational Resources Information Center

    Grover, Sharon D.

    2013-01-01

    According to the instructors and administrators at a local adult education (AE) program in Houston, Texas, retaining and graduating general education development (GED) students has been a constant challenge. Locating GED attendance barriers could enable AE programs to develop techniques that increase student retention and graduation rates. The…

  2. Course Retention Analysis. Focus Study.

    ERIC Educational Resources Information Center

    Mount San Antonio Coll., Walnut, CA.

    A study was conducted at Mount San Antonio College (MSAC), California, to analyze patterns in credit course retention between fall 1986 and spring 1989. The study investigated the development of course prerequisites based on faculty perceptions of the skills necessary for success and minimal skill levels associated with success; student assessment…

  3. Self-Managed Skill Retention.

    ERIC Educational Resources Information Center

    Marx, Robert D.

    1986-01-01

    Presents the Relapse Prevention model, which provides the structure in which managers can analyze potential lapses in their own skill retention. Discusses training goals, self-management, specific strategies, choosing a skill to retain, imagery and prediction, and holistic training. (CT)

  4. Employee voice and employee retention.

    PubMed

    Spencer, D G

    1986-09-01

    This study investigates the relationship between the extent to which employees have opportunities to voice dissatisfaction and voluntary turnover in 111 short-term, general care hospitals. Results show that, whether or not a union is present, high numbers of mechanisms for employee voice are associated with high retention rates. Implications for theory and research as well as management practice are discussed. PMID:10278801

  5. Managing Chemotherapy Side Effects: Swelling (Fluid Retention)

    MedlinePlus

    ... ancer I nstitute Managing Chemotherapy Side Effects Swelling (Fluid retention) “My hands and feet were swollen and ... at one time. Managing Chemotherapy Side Effects: Swelling (Fluid retention) Weigh yourself. l Weigh yourself at the ...

  6. 12 CFR 1002.12 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 8 2013-01-01 2013-01-01 false Record retention. 1002.12 Section 1002.12 Banks....12 Record retention. (a) Retention of prohibited information. A creditor may retain in its files... statutes or regulations. (b) Preservation of records—(1) Applications. For 25 months (12 months...

  7. 12 CFR 202.12 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 2 2011-01-01 2011-01-01 false Record retention. 202.12 Section 202.12 Banks... OPPORTUNITY ACT (REGULATION B) § 202.12 Record retention. (a) Retention of prohibited information. A creditor...) Applications. For 25 months (12 months for business credit, except as provided in paragraph (b)(5) of...

  8. 12 CFR 202.12 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 2 2014-01-01 2014-01-01 false Record retention. 202.12 Section 202.12 Banks... OPPORTUNITY ACT (REGULATION B) § 202.12 Record retention. (a) Retention of prohibited information. A creditor...) Applications. For 25 months (12 months for business credit, except as provided in paragraph (b)(5) of...

  9. 12 CFR 202.12 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 2 2013-01-01 2013-01-01 false Record retention. 202.12 Section 202.12 Banks... OPPORTUNITY ACT (REGULATION B) § 202.12 Record retention. (a) Retention of prohibited information. A creditor...) Applications. For 25 months (12 months for business credit, except as provided in paragraph (b)(5) of...

  10. 12 CFR 202.12 - Record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 2 2012-01-01 2012-01-01 false Record retention. 202.12 Section 202.12 Banks... OPPORTUNITY ACT (REGULATION B) § 202.12 Record retention. (a) Retention of prohibited information. A creditor...) Applications. For 25 months (12 months for business credit, except as provided in paragraph (b)(5) of...

  11. 12 CFR 1002.12 - Record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 8 2012-01-01 2012-01-01 false Record retention. 1002.12 Section 1002.12 Banks....12 Record retention. (a) Retention of prohibited information. A creditor may retain in its files... statutes or regulations. (b) Preservation of records—(1) Applications. For 25 months (12 months...

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

    ERIC Educational Resources Information Center

    National Student Clearinghouse, 2014

    2014-01-01

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

  13. Persistence-Retention. Snapshot™ Report, Spring 2015

    ERIC Educational Resources Information Center

    National Student Clearinghouse, 2015

    2015-01-01

    This Snapshot Report offers information on student persistence and retention rates for 2009-2013. It offers data on the following: (1) First-Year Persistence and Retention Rates for Students Who Start College at Four-Year Private Nonprofit Institutions; (2) First-Year Persistence and Retention Rates for Students Who Start College at Four-Year…

  14. Reframing Retention Strategy: A Focus on Progress

    ERIC Educational Resources Information Center

    Spittle, Brian

    2013-01-01

    Few words have dominated the vocabulary of college retention as has the word "persistence." Many institutions still struggle to engage faculty and administrators in building campuswide retention efforts, to find the organizational levers that translate the abstractions and complexities of retention theory into scalable and durable initiatives, and…

  15. Reframing Retention Strategy: A Focus on Profile

    ERIC Educational Resources Information Center

    Kalsbeek, David H.; Zucker, Brian

    2013-01-01

    Over 35 years of retention theory and literature have acknowledged the importance of institutional and student profiles in accounting for cross-sectional differences in retention and completion rates between types of colleges and universities. The first "P" within a 4 Ps framework of student retention--"profile"--recognizes that an institution's…

  16. 12 CFR 1002.12 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 8 2014-01-01 2014-01-01 false Record retention. 1002.12 Section 1002.12 Banks....12 Record retention. (a) Retention of prohibited information. A creditor may retain in its files... statutes or regulations. (b) Preservation of records—(1) Applications. For 25 months (12 months...

  17. Oxygen plasma immersion ion implantation treatment to enhance data retention of tungsten nanocrystal nonvolatile memory

    SciTech Connect

    Wang, Jer-Chyi Chang, Wei-Cheng; Lai, Chao-Sung; Chang, Li-Chun; Ai, Chi-Fong; Tsai, Wen-Fa

    2014-03-15

    Data retention characteristics of tungsten nanocrystal (W-NC) memory devices using an oxygen plasma immersion ion implantation (PIII) treatment are investigated. With an increase of oxygen PIII bias voltage and treatment time, the capacitance–voltage hysteresis memory window is increased but the data retention characteristics become degraded. High-resolution transmission electron microscopy images show that this poor data retention is a result of plasma damage on the tunneling oxide layer, which can be prevented by lowering the bias voltage to 7 kV. In addition, by using the elevated temperature retention measurement technique, the effective charge trapping level of the WO{sub 3} film surrounding the W-NCs can be extracted. This measurement reveals that a higher oxygen PIII bias voltage and treatment time induces more shallow traps within the WO{sub 3} film, degrading the retention behavior of the W-NC memory.

  18. Enhanced methodology for porting ion chromatography retention data.

    PubMed

    Park, Soo Hyun; Shellie, Robert A; Dicinoski, Greg W; Schuster, Georg; Talebi, Mohammad; Haddad, Paul R; Szucs, Roman; Dolan, John W; Pohl, Christopher A

    2016-03-01

    Porting is a powerful methodology to recalibrate an existing database of ion chromatography (IC) retention times by reflecting the changes of column behavior resulting from either batch-to-batch variability in the production of the column or the manufacture of new versions of a column. This approach has been employed to update extensive databases of retention data of inorganic and organic anions forming part of the "Virtual Column" software marketed by Thermo Fisher Scientific, which is the only available commercial optimization tool for IC separation. The current porting process is accomplished by performing three isocratic separations with two representative analyte ions in order to derive a porting equation which expresses the relationship between old and new data. Although the accuracy of retention prediction is generally enhanced on new columns, errors were observed on some columns. In this work, the porting methodology was modified in order to address this issue, where the porting equation is now derived by using six representative analyte ions (chloride, bromide, iodide, perchlorate, sulfate, and thiosulfate). Additionally, the updated porting methodology has been applied on three Thermo Fisher Scientific columns (AS20, AS19, and AS11HC). The proposed approach showed that the new porting methodology can provide more accurate and robust retention prediction on a wide range of columns, where average errors in retention times for ten test anions under three eluent conditions were less than 1.5%. Moreover, the retention prediction using this new approach provided an acceptable level of accuracy on a used column exhibiting changes in ion-exchange capacity. PMID:26860051

  19. Des Vents et des Jets Astrophysiques

    NASA Astrophysics Data System (ADS)

    Sauty, C.

    well expected result from the theory. Although, collimation may be conical, paraboloidal or cylindrical (Part 4), cylindrical collimation is the more likely to occur. The shape of outflows may then be used as a tool to predict physical conditions on the flows or on their source. L'éjection continue de plasma autour d'objets massifs est un phénomène largement répandu en astrophysique, que ce soit sous la forme du vent solaire, de vents stellaires, de jets d'étoiles en formation, de jets stellaires autour d'objets compacts ou de jets extra-galactiques. Cette zoologie diversifiée fait pourtant l'objet d'un commun effort de modélisation. Le but de cette revue est d'abord de présenter qualitativement le développement, depuis leur origine, des diverses théories de vents (Partie 1) et l'inter disciplinarité dans ce domaine. Il s'agit d'une énumération, plus ou moins exhaustive, des idées proposées pour expliquer l'accélération et la morphologie des vents et des jets, accompagnée d'une présentation sommaire des aspects observationnels. Cette partie s'abstient de tout aspect faisant appel au formalisme mathématique. Ces écoulements peuvent être décrits, au moins partiellement, en résolvant les équations magnétohydrodynamiques, axisymétriques et stationnaires. Ce formalisme, à la base de la plupart des théories, est exposé dans la Partie 2. Il permet d'introduire quantitativement les intégrales premières qu'un tel système possède. Ces dernières sont amenées à jouer un rôle important dans la compréhension des phénomènes d'accélération ou de collimation, en particulier le taux de perte de masse, le taux de perte de moment angulaire ou l'énergie du rotateur magnétique. La difficulté de modélisation réside dans l'existence de points critiques, propres aux équations non linéaires, qu'il faut franchir. La nature physique et la localisation de ces points critiques fait l'objet d'un débat important car ils sont la clef de voute de la r

  20. Neckband retention for lesser snow geese in the western Arctic

    USGS Publications Warehouse

    Samuel, M.D.; Goldberg, D.R.; Smith, A.E.; Baranyuk, W.; Cooch, E.G.

    2001-01-01

    Neckbands are commonly used in waterfowl studies (especially geese) to identify individuals for determination of movement and behavior and to estimate population parameters. Substantial neckband loss can adversely affect these research objectives and produce biased survival estimates. We used capture, recovery, and observation histories for lesser snow geese (Chen caerulescens caerulescens) banded in the western Arctic, 1993-1996, to estimate neckband retention. We found that neckband retention differed between snow goose breeding colonies at Wrangel Island, Russia, and Banks Island, Northwest Territories, Canada. Male snow geese had higher neckband loss than females, a pattern similar to that found for Canada geese (Branta canadensis) and lesser snow geese in Alaska. We found that the rate of neckband loss increased with time, suggesting that neckbands are lost as the plastic deteriorates. Survival estimates for geese based on resighting neckbands will be biased unless estimates are corrected for neckband loss. We recommend that neckband loss be estimated using survival estimators that incorporate recaptures, recoveries, and observations of marked birds. Research and management studies using neckbands should be designed to improve neckband retention and to include the assessment of neckband retention.

  1. Investigation of retention on bare silica using reversed-phase mobile phases at elevated temperatures.

    PubMed

    Bidlingmeyer, Brian A; Henderson, John

    2004-12-10

    The use of unbonded silica as a stationary phase in reversed-phase HPLC is described as a useful alternative to bonded phase columns for polar, lipophilic amines. Using four lipophilic amines, the role of temperature is shown to favorably impact both efficiency and selectivity, which is not universally seen when using bonded phases. As temperature is raised, retention drops on the silica column. The temperature behavior appears to support the hypothesis that retention is dependant upon electrostatic and adsorptive forces. PMID:15628161

  2. Gastro retention using polymer cocoons.

    PubMed

    Arnold, Julien; Hunkeler, David

    2015-02-01

    A gastro-retentive capsule has been prepared which is retained in the stomach for a period of 24h, providing a vehicle for the controlled delivery to the upper intestines. These "gastro cocoons" can resist passage through the sphincter of the stomach, and can retain a high drug payload (30%). They are made from oppositely charged polyelectrolytes and can swell to twice their initial volume. They are strong and also can resist 550 N of compressive force. They are based on filled pharmaceutical capsules which are visible to X-rays. Using ambroxol hydrochloride as a model drug linear, zero-order, release curves were obtained. PMID:25078789

  3. Retention and excretion of 95Zr-95Nb in humans.

    PubMed

    Thind, K S

    1995-12-01

    This note describes the retention and excretion of 95Zr-95Nb in humans based on a recent CANDU experience and a literature survey of reported cases. Two data bases, QUEST and INIS were used for the survey. Three reported cases were discovered: two for occupational exposures and one for public exposure from nuclear weapons fallout. Human lung retention from these three cases, plus whole body retention and some limited fecal excretion data from a recently occurred exposure at a CANDU station, were reviewed and tested against predictions based on ICRP Publication 30 model. Based on the fits of this model to the reported data it seems that the three occupational exposures exhibit class Y behavior while the public exposure exhibits class W behavior. For only one case is the chemical compound known with certainty: ZrO2. Zirconium oxides are currently classified as class W in ICRP Publications 30 and 54. This work confirms a suggestion that oxides of zirconium be classified as class Y and should be taken into account by the ICRP in its future publications. PMID:7493813

  4. Preheating temperature effect on tritium retention in VPS-W

    SciTech Connect

    Sato, M.; Uchimura, H.; Toda, K.; Oya, Y.; Okuno, K.; Tokunaga, T.; Watanabe, H.; Yoshida, N.; Hatano, Y.; Kasada, R.; Kimura, A.; Nagasaka, T.

    2015-03-15

    The W coating by Vacuum Plasma Spraying (VPS) technology is thought to be reasonable for most plasma facing components in future fusion reactors. In this paper the deuterium retention behavior for the Vacuum Plasma Spraying (VPS) tungsten (W) coating has been studied to demonstrate the tritium retention as a function of heating temperature. It has been found that two major deuterium desorption stages were observed at the temperature regions of 400 - 700 K (Stage 1) and 900 - 1100 K (Stage 2), considering that Stage 1 has been linked to the desorption of deuterium trapped by near surface and intrinsic defects, and Stage 2 has been related to the desorption of deuterium bound to impurities as C-D bonds. By heating the sample above 673 K, the major peak of C-1s shifted from C-O bond to C-C bond, where the retention of deuterium as Stage 2 has increased. Therefore it indicates that the hydrogen isotope retention was controlled by the amount of C-C bond in VPS, most of which was contaminated during the VPS coating process. The comparison of several samples (VPS-W with shading, VPS-W without shading and Polycrystalline W (PCW)) shows that the carbon impurity has a large affinity with deuterium and makes stable trapping states compared to that with intrinsic defects and grain boundaries. However, most of them was reduced by heating at 1173 K. Therefore, heating treatment is quite important to get rid of carbon impurities and refrain higher tritium retention in VPS. (authors)

  5. Radionuclide Retention in Concrete Wasteforms

    SciTech Connect

    Wellman, Dawn M.; Jansik, Danielle P.; Golovich, Elizabeth C.; Cordova, Elsa A.

    2012-09-24

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of LLW and MLLW, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

  6. Fission-product retention in HTGR fuels

    SciTech Connect

    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.

  7. Therapeutic Alliance and Retention in Brief Strategic Family Therapy: A Mixed-Methods Study.

    PubMed

    Sheehan, Alyson H; Friedlander, Myrna L

    2015-10-01

    We explored how the therapeutic alliance contributed to retention in Brief Strategic Family Therapy by analyzing videotapes of eight-first sessions in which four therapists worked with one family that stayed in treatment and one family that dropped out. Although behavioral exchange patterns between clients and therapists did not differ by retention status, positive therapist alliance-related behavior followed negative client alliance behavior somewhat more frequently in the retained cases. In the qualitative aspect of the study, four family therapy experts each viewed two randomly assigned sessions and commented on their quality without knowing the families' retention status. A qualitative analysis of the audiotaped commentaries revealed 18 alliance-related themes that were more characteristic of either the retained or the nonretained cases. PMID:25640754

  8. Retention behavior of common mono- and divalent cations on calcinated silica gel columns in ion chromatography with conductimetric detection and the use of nitric acid, containing crown ethers, as eluents.

    PubMed

    Ohta, Kazutoku; Kusumoto, Keiji; Takao, Yasumasa; Towata, Atsuya; Kawakami, Shoji; Murase, Yoshio; Ohashi, Masayoshi

    2002-05-17

    Ion chromatographic behavior of common mono- and divalent cations (Li+, Na+, NH4+, K+, Mg2+ and Ca2+) on columns packed with silica gels (Super Micro Bead Silica Gel B-5, SMBSG B-5) calcinated at 200, 400, 600, 800 and 1000 degrees C for 5 h was investigated using nitric acid containing crown ethers [18-crown-6 (1,4,7,10,13,15-hexaoxacyclooctadecane) and 15-crown-5 (1,4,7,10,13-pentaoxacyclopentadecane)] as eluent. When using 0.5 mM HNO3 as the eluent, the calcination had almost no effect on the improvement of peak resolution between these mono- and divalent cations. In contrast, when using 0.5 mM HNO3 containing crown ethers as the eluent, with increasing the calcinating temperature, the amount of crown ethers adsorbed on the corresponding calcinated SMBSG B-5 silica gels columns increased and, as a consequence, peak resolution between these mono- and divalent cations was quite improved. Excellent simultaneous separation of these mono- and divalent cations was achieved on column (150x4.6 mm I.D.) packed with the SMBSG B-5 silica gel calcinated at 1000 degrees C by elution with 0.5 mM HNO3 containing either 1.0 mM 18-crown-6 or 5.0 mM 15-crown-5. PMID:12108647

  9. Reticulation des fibres lignocellulosiques

    NASA Astrophysics Data System (ADS)

    Landrevy, Christel

    Pour faire face à la crise économique la conception de papier à valeur ajoutée est développée par les industries papetières. Le but de se projet est l'amélioration des techniques actuelles de réticulation des fibres lignocellulosiques de la pâte à papier visant à produire un papier plus résistant. En effet, lors des réactions de réticulation traditionnelles, de nombreuses liaisons intra-fibres se forment ce qui affecte négativement l'amélioration anticipée des propriétés physiques du papier ou du matériau produit. Pour éviter la formation de ces liaisons intra-fibres, un greffage sur les fibres de groupements ne pouvant pas réagir entre eux est nécessaire. La réticulation des fibres par une réaction de « click chemistry » appelée cycloaddition de Huisgen entre un azide et un alcyne vrai, catalysée par du cuivre (CuAAC) a été l'une des solutions trouvée pour remédier à ce problème. De plus, une adaptation de cette réaction en milieux aqueux pourrait favoriser son utilisation en milieu industriel. L'étude que nous désirons entreprendre lors de ce projet vise à optimiser la réaction de CuAAC et les réactions intermédiaires (propargylation, tosylation et azidation) sur la pâte kraft, en milieu aqueux. Pour cela, les réactions ont été adaptées en milieu aqueux sur la cellulose microcristalline afin de vérifier sa faisabilité, puis transférée à la pâte kraft et l'influence de différents paramètres comme le temps de réaction ou la quantité de réactifs utilisée a été étudiée. Dans un second temps, une étude des différentes propriétés conférées au papier par les réactions a été réalisée à partir d'une série de tests papetiers optiques et physiques. Mots Clés Click chemistry, Huisgen, CuAAC, propargylation, tosylation, azidation, cellulose, pâte kraft, milieu aqueux, papier.

  10. Formation and retention of methane in coal

    SciTech Connect

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seams and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.

  11. Surface morphology and deuterium retention in tungsten exposed to high flux D plasma at high temperatures

    NASA Astrophysics Data System (ADS)

    Jia, Y. Z.; De Temmerman, G.; Luo, G.-N.; Xu, H. Y.; Li, C.; Fu, B. Q.; Liu, W.

    2015-02-01

    Surface modifications and deuterium retention induced in tungsten by high fluxes (1024 m-2 s-1) low energy (38 eV) deuterium ions were studied as a function of surface temperature. Blister formation was studied by scanning electron microscopy and electron backscatter diffraction, while deuterium retention was measured by thermal desorption spectroscopy. Blisters are observed on the surface exposed at different temperatures, ranging from 493 K to 1273 K. The blister density and D retention decrease with the increasing exposure temperature. The formation of blisters at high temperatures is attributed to the high flux of D plasma. At 943 K, with the increasing fluence, there is trend to the saturation of D retention and blister density. The defects caused by plasma exposure have an important effect on the D trapping and blistering behavior. The formation of blisters has a strong relationship with slipping system of tungsten.

  12. Predicting the chromatographic retention of polymers: poly(methyl methacrylate)s and polyacryate blends.

    PubMed

    Bashir, Mubasher A; Radke, Wolfgang

    2007-09-01

    The suitability of a retention model especially designed for polymers is investigated to describe and predict the chromatographic retention behavior of poly(methyl methacrylate)s as a function of mobile phase composition and gradient steepness. It is found that three simple yet rationally chosen chromatographic experiments suffice to extract the analyte specific model parameters necessary to calculate the retention volumes. This allows predicting accurate retention volumes based on a minimum number of initial experiments. Therefore, methods for polymer separations can be developed in relatively short time. The suitability of the virtual chromatography approach to predict the separation of polymer blend is demonstrated for the first time using a blend of different polyacrylates. PMID:17586517

  13. Predicting health plan member retention from satisfaction surveys: the moderating role of intention and complaint voicing.

    PubMed

    Huppertz, John W

    2008-01-01

    Many health plans have tried to increase member retention by improving their scores on customer satisfaction surveys. However, prior research has demonstrated weak relationships between member satisfaction and retention, suggesting that other variables are needed to understand how satisfaction impacts member retention. In a longitudinal study 4,806 health plan members who completed satisfaction surveys were re-assessed three years later; we compared measures of satisfaction, intention, and complaining behavior from voluntary disenrollees and retained members. The relationship between satisfaction and retention was moderated by members' intentions to disenroll. The findings suggest that health plans can enhance the predictive validity of their satisfaction surveys by including measures of both satisfaction and intentions. PMID:19064478

  14. Radionuclide Retention in Concrete Wasteforms

    SciTech Connect

    Bovaird, Chase C.; Jansik, Danielle P.; Wellman, Dawn M.; Wood, Marcus I.

    2011-09-30

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. The information present in the report provides data that (1) measures the effect of concrete wasteform properties likely to influence radionuclide migration; and (2) quantifies the rate of carbonation of concrete materials in a simulated vadose zone repository.

  15. Retention Revisited: R=E, Id+E & In, Iv.

    ERIC Educational Resources Information Center

    Seidman, Alan

    1996-01-01

    Recent research on college student attrition is examined for trends, and it is suggested that the common perspective on retention and attrition is too narrow; it should be viewed from three perspectives: within-course retention; program retention; and institutional retention rate. Recommended for retention (R) is early (E) identification (Id) plus…

  16. Developing Successful Retention Programs: An Interview with Michael Hovland.

    ERIC Educational Resources Information Center

    Kluepfel, Gail A.; Hovland, Michael

    1994-01-01

    Michael Hovland, the senior consultant at Noel-Levitz Centers, responds to questions about summer bridge programs, first-year seminar programs, Rutgers' retention model, faculty reactions to retention programs, the impact of retention programs on institutional mission, administrative involvement in retention, student assessment, retention efforts…

  17. 10 CFR 37.103 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 1 2014-01-01 2014-01-01 false Record retention. 37.103 Section 37.103 Energy NUCLEAR REGULATORY COMMISSION PHYSICAL PROTECTION OF CATEGORY 1 AND CATEGORY 2 QUANTITIES OF RADIOACTIVE MATERIAL Records § 37.103 Record retention. Licensees shall maintain the records that are required by...

  18. 12 CFR 1013.8 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 8 2014-01-01 2014-01-01 false Record retention. 1013.8 Section 1013.8 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION CONSUMER LEASING (REGULATION M) § 1013.8 Record retention. A lessor shall retain evidence of compliance with the requirements imposed by this part,...

  19. 12 CFR 213.8 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 2 2011-01-01 2011-01-01 false Record retention. 213.8 Section 213.8 Banks and Banking FEDERAL RESERVE SYSTEM BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM CONSUMER LEASING (REGULATION M) § 213.8 Record retention. A lessor shall retain evidence of compliance with the...

  20. Minority Teacher Recruitment and Retention Strategies

    ERIC Educational Resources Information Center

    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…

  1. 12 CFR 609.945 - Records retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 7 2012-01-01 2012-01-01 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,...

  2. 12 CFR 609.945 - Records retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 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,...

  3. 12 CFR 609.945 - Records retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 7 2013-01-01 2013-01-01 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,...

  4. 12 CFR 226.25 - Record retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Record retention. 226.25 Section 226.25 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.25 Record retention. (a) General rule. A creditor...

  5. 12 CFR 1026.25 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 9 2014-01-01 2014-01-01 false Record retention. 1026.25 Section 1026.25 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION TRUTH IN LENDING (REGULATION Z) Miscellaneous § 1026.25 Record retention. (a) General rule. A creditor shall retain evidence of compliance with...

  6. 12 CFR 1026.25 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 8 2013-01-01 2013-01-01 false Record retention. 1026.25 Section 1026.25 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION TRUTH IN LENDING (REGULATION Z) Miscellaneous § 1026.25 Record retention. (a) General rule. A creditor shall retain evidence of compliance with...

  7. 12 CFR 226.25 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 3 2013-01-01 2013-01-01 false Record retention. 226.25 Section 226.25 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM (CONTINUED) TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.25 Record retention. (a) General rule....

  8. 12 CFR 226.25 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Record retention. 226.25 Section 226.25 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN LENDING (REGULATION Z) Miscellaneous § 226.25 Record retention. (a) General rule. A creditor...

  9. 12 CFR 1026.25 - Record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 8 2012-01-01 2012-01-01 false Record retention. 1026.25 Section 1026.25 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION TRUTH IN LENDING (REGULATION Z) Miscellaneous § 1026.25 Record retention. (a) General rule. A creditor shall retain evidence of compliance with...

  10. Comparative Aggregate Patterns of Grade Retention Rates.

    ERIC Educational Resources Information Center

    Morris, Don R.

    A search for patterns in grade retention rates across grades 1-12 to construct simulation research models is described in this paper. Aggregate data from Shepard and Smith (1989) on grade retention rates from 12 American states for the year 1979-80 and from 11 states for 1985-86 were examined for across-grade patterns, supplemented by Dade County…

  11. Measuring Up: Benchmarking Graduate Retention. IES Report.

    ERIC Educational Resources Information Center

    Tyers, C.; Perryman, S.; Barber, L.

    Retention of college graduates by employers across the United Kingdom was examined. Data were collected through a survey of 362 organizations and interviews with 36 employers and their graduate employees. Most employers were unworried by their levels of graduate retention; two-thirds expected to keep new recruits for the foreseeable future. Rates…

  12. An Orientation Course and Community College Retention

    ERIC Educational Resources Information Center

    Derby, Dustin; Smith, Thomas

    2004-01-01

    Orientation and retention programs are common in institutions of higher education. The potential association between orientation programs and student retention, particularly within the community college sector, has long been neglected. This study presents an institutional view of a potential associative relationship between an orientation course…

  13. Increasing Retention without Increasing Study Time

    ERIC Educational Resources Information Center

    Rohrer, Doug; Pashler, Hal

    2007-01-01

    Because people forget much of what they learn, students could benefit from learning strategies that provide long-lasting knowledge. Yet surprisingly little is known about how long-term retention is most efficiently achieved. Here we examine how retention is affected by two variables: the duration of a study session and the temporal distribution…

  14. Effective Teacher Retention Bonuses: Evidence From Tennessee

    ERIC Educational Resources Information Center

    Springer, Matthew G.; Swain, Walker A.; Rodriguez, Luis A.

    2016-01-01

    We report findings from a quasi-experimental evaluation of the recently implemented US$5,000 retention bonus program for effective teachers in Tennessee's Priority Schools. We estimate the impact of the program on teacher retention using a fuzzy regression discontinuity design by exploiting a discontinuity in the probability of treatment…

  15. Enrollment and Retention: A Private College Consortium.

    ERIC Educational Resources Information Center

    Green, Kenneth C.

    A consortium program of eight private colleges in Southern California that focuses on student retention efforts is described. Each college has a retention task force consisting of faculty, administrators, student affairs staff, and students. A steering committee with one representative from each college, generally the dean of students, coordinates…

  16. 49 CFR 236.1037 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Records retention. 236.1037 Section 236.1037 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Systems § 236.1037 Records retention. (a) Each railroad with a PTC system required to be installed...

  17. Managing human resources to improve employee retention.

    PubMed

    Arnold, Edwin

    2005-01-01

    Managers face increased challenges as the demand for health care services increases while the supply of employees with the requisite skills continues to lag. Employee retention will become more important in the effort to service health care needs. Appropriate human resource management strategies and policies implemented effectively can significantly assist managers in dealing with the employee retention challenges ahead. PMID:15923925

  18. The Psychology Underlying Successful Retention Practices.

    ERIC Educational Resources Information Center

    Bean, John; Eaton, Shevawn Bogdan

    2002-01-01

    Describes the psychological processes that lead to academic and social integration based on a retention model proposed by the authors. Describes how successful retention programs such as learning communities, freshman interest groups, tutoring, and orientation rely on psychological processes. Four psychological theories form the basis for…

  19. 21 CFR 600.13 - Retention samples.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 7 2014-04-01 2014-04-01 false Retention samples. 600.13 Section 600.13 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS BIOLOGICAL PRODUCTS: GENERAL Establishment Standards § 600.13 Retention samples. Manufacturers shall...

  20. 21 CFR 600.13 - Retention samples.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 7 2013-04-01 2013-04-01 false Retention samples. 600.13 Section 600.13 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS BIOLOGICAL PRODUCTS: GENERAL Establishment Standards § 600.13 Retention samples. Manufacturers shall...

  1. 21 CFR 600.13 - Retention samples.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 7 2012-04-01 2012-04-01 false Retention samples. 600.13 Section 600.13 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS BIOLOGICAL PRODUCTS: GENERAL Establishment Standards § 600.13 Retention samples. Manufacturers shall...

  2. A Model for Freshman Engineering Retention

    ERIC Educational Resources Information Center

    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…

  3. Profile in Action: Linking Admission and Retention

    ERIC Educational Resources Information Center

    Cortes, Carla M.

    2013-01-01

    A profile-oriented retention strategy embraces the admission process as a powerful lever in improving retention and completion rates and recognizes that the student profile can be shaped by changes in admission policies or priorities--even within the current market position of the institution. In addition, the student body can be oriented toward…

  4. 19 CFR 10.308 - Records retention.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Records retention. 10.308 Section 10.308 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Canada Free Trade Agreement § 10.308 Records retention. (a) Importer....

  5. 12 CFR 609.945 - Records retention.

    Code of Federal Regulations, 2010 CFR

    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,...

  6. The Grade Retention/Social Promotion Debate.

    ERIC Educational Resources Information Center

    Lindelow, John

    1985-01-01

    This publication focuses on the retention/promotion debate regarding failing and low-achieving students. An introductory essay describes the inherent limitation in the research done on this issue--the impossibility of obtaining an appropriate control group--and suggests that the retention/promotion quandary can best be resolved by accommodating…

  7. Novel Word Retention in Sequential Bilingual Children

    ERIC Educational Resources Information Center

    Kan, Pui Fong

    2014-01-01

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

  8. Emotional Intelligence and Nursing Student Retention

    ERIC Educational Resources Information Center

    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…

  9. Using Enrollment Data to Predict Retention Rate

    ERIC Educational Resources Information Center

    Bingham, Melissa A.; Solverson, Natalie Walleser

    2016-01-01

    First- to second-year retention rates are one metric reported by colleges and universities to convey institutional success to a variety of external constituents. But how much of a retention rate is institutional inputs, and how much can be understood by examining student inputs? The authors utilize multi-year, multi-institutional data to examine…

  10. Retention Models for Minority College Students.

    ERIC Educational Resources Information Center

    Obiakor, Festus E.; Harris-Obiakor, Pauline

    This paper discusses retention techniques that can be used with minority students at predominantly white colleges, focusing on four phases that are critical to the retention and academic achievement of minority students: acceptance, acclimatization, responsibility, and productivity. In the acceptance phase, the college community should attempt to…

  11. 14 CFR 291.23 - Record retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... § 291.23 Record retention. (a) The provisions of 14 CFR part 249, Preservation of air carrier accounts... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Record retention. 291.23 Section 291.23 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS)...

  12. Faculty Personality: A Factor of Student Retention

    ERIC Educational Resources Information Center

    Shaw, Cassandra S.; Wu, Xiaodong; Irwin, Kathleen C.; Patrizi, L. A. Chad

    2016-01-01

    The purpose of this study was to determine the relationship between student retention and faculty personality as it was hypothesized that faculty personality has an effect on student retention. The methodology adopted for this study was quantitative and in two parts 1) using linear regression models to examine the impact or causality of faculty…

  13. Photoelastic analysis of stress distribution in different retention systems for facial prosthesis.

    PubMed

    Goiato, Marcelo Coelho; Ribeiro, Paula do Prado; Pellizzer, Eduardo Piza; Garcia Júnior, Idelmo Rangel; Pesqueira, Aldiéris Alves; Haddad, Marcela Filiè

    2009-05-01

    The aim of this study was to assess the behavior and stress distribution of 3 retention systems associated with implant for facial prosthesis by using the photoelasticity method. A photoelastic model was made from the replica of the orbital region on the left side of a dry skull with two 4-mm implants fixed in the superior orbital region. Three facial prosthetic retention systems were made for this study: O'ring, bar-clip, and magnets. The set (model/retention systems/prosthesis) was placed in a polariscope, and then traction began to be applied to the retention systems. The limit values for removal of the retention system were obtained by tests performed in an EMIC Universal test machine. The results were obtained by observation during the experiments and by photographic record of the stress behavior in the photoelastic model, resulting from the traction of the retention systems. In the magnet system, a lowest formation of fringes was verified both around and between the implants; in the O'ring system, the formation of photoelastic fringes was noted between the implants in the apical region; and in the bar-clip system, there was a greater concentration of colored fringes in the regions between the implants and cervical area. Based on the results obtained, it was concluded that the retention systems produced different stress distribution characteristics that, in general, were concentrated in the area around the implants, and the highest concentration of fringes, in increasing order, occurred in the retention systems of the magnets, O'ring, and bar-clip. PMID:19381103

  14. Novel word retention in sequential bilingual children.

    PubMed

    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. PMID:23672812

  15. Retention modelling in hydrophilic interaction chromatography.

    PubMed

    Euerby, Melvin R; Hulse, Jennifer; Petersson, Patrik; Vazhentsev, Andrey; Kassam, Karim

    2015-12-01

    The retention behaviour of acidic, basic and quaternary ammonium salts and polar neutral analytes has been evaluated on acidic, basic and neutral hydrophilic interaction chromatography (HILIC) stationary phases as a function of HILIC operating parameters such as MeCN content, buffer concentration, pH and temperature. Numerous empirical HILIC retention models (existing and newly developed ones) have been assessed for their ability to describe retention as a function of the HILIC operating parameters investigated. Retention models have been incorporated into a commercially available retention modelling programme (i.e. ACD/LC simulator) and their accuracy of retention prediction assessed. The applicability of HILIC modelling using these equations has been demonstrated in the two-dimensional isocratic (i.e. buffer concentration versus MeCN content modelling) and one-dimensional gradient separations for a range of analytes of differing physico-chemical properties on the three stationary phases. The accuracy of retention and peak width prediction was observed to be comparable to that reported in reversed-phase chromatography (RPC) retention modelling. Intriguingly, our results have confirmed that the use of gradient modelling to predict HILIC isocratic conditions and vice versa is not reliable. A relative ranking of the importance of the retention and selectivity of HILIC operating parameters has been determined using statistical approaches. For retention, the order of importance was observed to be organic content > stationary phase > temperature ≈ mobile phase pH (i.e. pH 3-6 which mainly effects the ionization of the analyte) ≈ buffer concentration. For selectivity, the nature of the stationary phase > mobile phase pH > buffer concentration > temperature > organic content. PMID:26563113

  16. Practice and retention of nonwords in adults who stutter

    PubMed Central

    Sasisekaran, Jayanthi; Weisberg, Sanford

    2014-01-01

    Purpose We investigated short-term practice and retention of nonwords in 10 adults who stutter (Mean age = 30.7 years, SD = 15.1) and age and sex-matched 10 control participants (Mean age = 30.8 years, SD = 14.9). Methods Participants were required to repeat nonwords varying in length (3, 4, 6 syllables), phonotactic constraint (PC vs. NPC, on 3-syllable nonwords only), and complexity (simple, complex). They were tested twice with one hour gap between sessions. Results Logistic mixed model of speech accuracy revealed that the AWS showed a significantly lower probability of correct responses with increasing length and complexity. Analysis of speech kinematics revealed practice effects within Session 1 in AWS seen as a reduction in movement variability for the 3-syllable nonwords; the control group was performing at ceiling at this length. For the 4-syllable nonwords, the control group showed a significant reduction in movement variability with practice, and retained this reduction in Session 2, while the AWS group did not show practice or retention. Group differences were not evident at the 6-syllable level. Conclusions Group differences in speech accuracy suggest differences in phonemic encoding and/or speech motor processes. Group differences in changes in movement variability within and between sessions suggest reduced practice and retention in AWS. Relevance of the combined use of both behavioral and kinematic measures to interpret the nature of the skill acquisition deficit in persons who stutter is discussed. PMID:25173457

  17. 40 CFR 160.195 - Retention of records.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... LABORATORY PRACTICE STANDARDS Records and Reports § 160.195 Retention of records. (a) Record retention requirements set forth in this section do not supersede the record retention requirements of any...

  18. Average Soil Water Retention Curves Measured by Neutron Radiography

    SciTech Connect

    Cheng, Chu-Lin; Perfect, Edmund; Kang, Misun; Voisin, Sophie; Bilheux, Hassina Z; Horita, Juske; Hussey, Dan

    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.

  19. Selection and retention of nurses.

    PubMed

    Muncey, T

    1998-02-01

    The selection and retention of suitable nurses has occupied the thoughts of many people who have a vested interest in maintaining standards and avoiding loss of resources. By drawing conclusions from inadequate findings inappropriate recommendations may be made. In a study that considers the psychological profiles of nurses, it would appear that it is self-esteem and a 'need to be needed' that is a crucial facet of nurses ability to cope with the job of nursing; a job that encourages the characteristics of individualism, in a working environment involving caring, that epitomises the values of connectedness. This paradox leads to nurses' inability to cope and subsequently leave the profession using one of the many acceptable labels that are widely documented. Acceptance of the underlying causes for this attrition would necessitate better support services for vulnerable nurses allowing them to recognize their own needs, and gain a personal understanding of how their vulnerability might echo that of people in their care. PMID:9515654

  20. Evaluation of the retention of endodontic implants.

    PubMed

    Maniatopoulos, C; Pilliar, R M; Smith, D C

    1988-04-01

    The study investigated the retentive strength of endodontic implants measured by forced removal (pull-out or push-out tests) as a function of implant design and cement type. Smooth-tapered, threaded, and an innovative porous-surfaced implant were evaluated. Specimens were cemented in single-rooted human teeth with five different cements: zinc phosphate, polycarboxylate, glass ionomer, silicophosphate, or AH-26. The results indicated superior retention for the threaded and porous-surfaced implants, and stronger retention with glass-ionomer and AH-26 cements. PMID:3162990

  1. A strategic approach to employee retention.

    PubMed

    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. PMID:12656028

  2. Médecine des voyages

    PubMed Central

    Aw, Brian; Boraston, Suni; Botten, David; Cherniwchan, Darin; Fazal, Hyder; Kelton, Timothy; Libman, Michael; Saldanha, Colin; Scappatura, Philip; Stowe, Brian

    2014-01-01

    Résumé Objectif Définir la pratique de la médecine des voyages, présenter les éléments fondamentaux d’une consultation complète préalable aux voyages à des voyageurs internationaux et aider à identifier les patients qu’il vaudrait mieux envoyer en consultation auprès de professionnels de la médecine des voyages. Sources des données Les lignes directrices et les recommandations sur la médecine des voyages et les maladies liées aux voyages publiées par les autorités sanitaires nationales et internationales ont fait l’objet d’un examen. Une recension des ouvrages connexes dans MEDLINE et EMBASE a aussi été effectuée. Message principal La médecine des voyages est une spécialité très dynamique qui se concentre sur les soins préventifs avant un voyage. Une évaluation exhaustive du risque pour chaque voyageur est essentielle pour mesurer avec exactitude les risques particuliers au voyageur, à son itinéraire et à sa destination et pour offrir des conseils sur les interventions les plus appropriées en gestion du risque afin de promouvoir la santé et prévenir les problèmes médicaux indésirables durant le voyage. Des vaccins peuvent aussi être nécessaires et doivent être personnalisés en fonction des antécédents d’immunisation du voyageur, de son itinéraire et du temps qu’il reste avant son départ. Conclusion La santé et la sécurité d’un voyageur dépendent du degré d’expertise du médecin qui offre le counseling préalable à son voyage et les vaccins, au besoin. On recommande à ceux qui donnent des conseils aux voyageurs d’être conscients de l’ampleur de cette responsabilité et de demander si possible une consultation auprès de professionnels de la médecine des voyages pour tous les voyageurs à risque élevé.

  3. Retention and release behavior of insulin in chitosan gel beads.

    PubMed

    Kofuji, Kyoko; Akamine, Hiroyuki; Oshirabe, Hitomi; Maeda, Yasuyo; Murata, Yoshifumi; Kawashima, Susumu

    2003-01-01

    Chitosan (CS) gel beads were prepared in a 10% (w/v) aqueous amino acid solution (pH 9.0) as a vehicle for delivering peptide and protein drugs. CS gel beads with a weight-average molecular weight of (16-280) x 10(4) were employed in this study. Preparation of the CS gel beads was affected by properties such as molecular weight and degree of deacetylation. Insulin, which is commonly used to assess protein drug delivery, was retained in the CS gel beads. Drug release from the CS gel beads was governed by diffusion of drug from the gel matrix. Sustained release of insulin from the CS gel beads was observed, despite the fact that insulin is a comparatively water-soluble drug. because insulin formed a complex with CS. Modification of the CS gel matrix by chondroitin sulfate inhibited release of insulin from the gel beads. CS gel beads were implanted into air pouches prepared subcutaneously on the dorsal surface of diabetic mice in order to investigate the efficacy of insulin retained in the CS beads. Blood glucose levels were found to be reduced after implantation of CS gel beads retaining insulin. CS gel beads may possibly improve the stability and control of insulin release. These observations indicate that CS beads are a promising biocompatible and biodegradable vehicle for peptide and protein delivery. PMID:14768911

  4. The Causal Effects of Grade Retention on Behavioral Outcomes

    ERIC Educational Resources Information Center

    Mariano, Lou; Martorell, Paco

    2015-01-01

    Requiring a failing student to repeat a grade is, of course, not a novel idea. The theory behind test-based promotion policies is that students who fail to demonstrate a sufficient understanding of their current grade's curriculum lack the prerequisite proficiency to fully engage in the following grade. This view recognizes the cumulative nature…

  5. Academic Dishonesty: Behaviors, Sanctions, and Retention of Adjudicated College Students

    ERIC Educational Resources Information Center

    Olafson, Lori; Schraw, Gregory; Kehrwald, Nicholas

    2014-01-01

    Academic dishonesty, also known as academic misconduct, includes a variety of actions such as plagiarism, cheating on tests using text messaging or concealed notes, exchanging work with other students, buying essays from students or on the Internet, and having other students write examinations (Diekhoff, LaBeff, Shinohara, & Yasukawa, 1999;…

  6. Application of a quantitative structure retention relationship approach for the prediction of the two-dimensional gas chromatography retention times of polycyclic aromatic sulfur heterocycle compounds.

    PubMed

    Gieleciak, Rafal; Hager, Darcy; Heshka, Nicole E

    2016-03-11

    Information on the sulfur classes present in petroleum is a key factor in determining the value of refined products and processing behavior in the refinery. A large part of the sulfur present is included in polycyclic aromatic sulfur heterocycles (PASHs), which in turn are difficult to desulfurize. Furthermore, some PASHs are potentially more mutagenic and carcinogenic than polycyclic aromatic hydrocarbons, PAHs. All of this calls for improved methods for the identification and quantification of individual sulfur species. Recent advances in analytical techniques such as comprehensive two-dimensional gas chromatography (GC×GC) have enabled the identification of many individual sulfur species. However, full identification of individual components, particularly in virgin oil fractions, is still out of reach as standards for numerous compounds are unavailable. In this work, a method for accurately predicting retention times in GC×GC using a QSRR (quantitative structure retention relationship) method was very helpful for the identification of individual sulfur compounds. Retention times for 89 saturated, aromatic, and polyaromatic sulfur-containing heterocyclic compounds were determined using two-dimensional gas chromatography. These retention data were correlated with molecular descriptors generated with CODESSA software. Two independent QSRR relationships were derived for the primary as well as the secondary retention characteristics. The predictive ability of the relationships was tested by using both independent sets of compounds and a cross-validation technique. When the corresponding chemical standards are unavailable, the equations developed for predicting retention times can be used to identify unknown chromatographic peaks by matching their retention times with those of sulfur compounds of known molecular structure. PMID:26879453

  7. Retention and leaching of nitrite by municipal solid waste incinerator bottom ash under the landfill circumstance.

    PubMed

    Yao, Jun; Kong, Qingna; Zhu, Huayue; Long, Yuyang; Shen, Dongsheng

    2015-01-01

    The retention and leaching of nitrite by municipal solid waste incinerator (MSWI) bottom ash could affect its migration in the landfill. In this study, the effect of the dosage of MSWI bottom ash as well as the variation of the landfill environmental parameters including pH, anions and organic matter on the nitrite retention and leaching behavior was investigated by batch experiments. The highest removal percentage (73.0%) of nitrite was observed when the dosage of MSWI bottom ash was 10 g L(-1) in 2 mg L(-1) nitrite solution. Further increase of the dosage would retard the retention, as the nitrite leaching from MSWI bottom ash was enhanced. The optimum retention of nitrite was observed when the pH was 5.0, while the leaching of nitrite showed a consistent reduction with the increase of pH. Besides, the presence of Cl(-), SO4(2)(-) and acetic acid could enhance the leaching of nitrite and mitigate the retention process. However, the retention of nitrite was enhanced by PO4(3)(-), which was probably due to the formation of the apatite, an active material for the adsorption of the nitrite. These results suggested that MSWI bottom ash could affect the migration of nitrite in the landfill, which was related to the variation of the landfill circumstance. PMID:25033242

  8. Magnitude and distribution of stresses in composite resin and sound dentine interface with mechanical retentions

    PubMed Central

    Borie, Eduardo; Orsi, Iara-Augusta; Del Sol, Mariano

    2015-01-01

    Background Adhesive systems are constantly subjected to mechanical and chemical stresses that negatively impact the integrity and durability of the dentine-adhesive interface. Despite the lack of evidence to support or reject the clinical indication for mechanical retention, the potential further contribution of these preparations to the behavior of the composite resin-sound dentine bond has been rarely addressed. The authors evaluated by finite element analysis the effect of mechanical retention on the magnitude and distribution of stresses in a composite resin-sound dentin bonding interface when subjected to tensile and shear forces. Material and Methods A three-dimensional model was created based on three cylindrical volumes representing the sound dentin, adhesive system, and composite resin. From this main model, two models were designed to simulate dentine bonding: 1) a model with no mechanical retention, which considered flat adhesion; and 2) a model with retention, which considered four hemispherical holes on the dentine surface. Both groups were subjected to linear static analysis under tensile and shear loading of 200N. Results At the model with retentions’ bonding interface under tensile and shear loading, a concentration of Von Mises equivalent stress was observed within the retentions, with a reduction of those stresses on the bonding boundary surface. Conclusions Additional mechanical retention increases the tensile strength of the sound dentin-composite resin bonding interface, promoting a decrease in the magnitude of the stresses and their redistribution under tensile and shear loading. Key words:Adhesion, composite resins, dentine, finite element analysis. PMID:26155338

  9. Online Mate-Retention Tactics on Facebook Are Associated With Relationship Aggression.

    PubMed

    Brem, Meagan J; Spiller, Laura C; Vandehey, Michael A

    2015-10-01

    A measure of Facebook-related mate-retention tactics was developed to investigate the relationship between online behaviors and intimate partner aggression. One hundred and seventy-seven young adults (65 men, 112 women) completed questionnaires that included measures of online and offline mate-retention tactics, Facebook jealousy, Facebook surveillance, and intimate partner violence. A factor analysis yielded four subscales for the Facebook Mate-Retention Tactic Inventory (FMRTI): Care and Affection, Jealousy and Surveillance, Possession Signals, and Punishment of Infidelity Threat. The FMRTI total scores were positively correlated with Facebook jealousy, Facebook surveillance, and use of offline mate-retention tactics. The Jealousy and Surveillance subscale uniquely predicted intimate partner psychological and physical aggression over and above existing measures. Facebook mate-retention tactics fully mediated the relation between Facebook jealousy and both intimate partner psychological and physical aggression. The current study provides preliminary evidence for conceptualizing Facebook as an environment for the use of mate-retention tactics that have real-life implications for intimate partner violence. PMID:25339609

  10. An Exploratory Study of Job Satisfaction, Retention, and Performance of Navy Enlisted Men.

    ERIC Educational Resources Information Center

    Stoloff, Peter H.

    The paper examines the relationship of two aspects of job satisfaction: satisfaction with the work itself (job content) and satisfaction with the job environment (job context) to retention behavior and measures of on-the-job performance of first-term Naval enlisted men. While both job content and job context factors were found to be important…

  11. 75 FR 7370 - Federal Motor Vehicle Safety Standards; Door Locks and Door Retention Components

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-19

    ... Safety Standard (FMVSS) No. 206, Door Locks and Door Retention Components (49 CFR 571.206) (72 FR 5385... September 1, 2009, to September 1, 2010. (74 FR 35131; Docket No. NHTSA 2009-0116.) The original effective... some human behavior.'' 72 FR at 5391. In its petition, Advocates stated that its NPRM comments...

  12. A REVIEW OF EFFORTS TO ORGANIZE INFORMATION ABOUT HUMAN LEARNING, TRANSFER, AND RETENTION.

    ERIC Educational Resources Information Center

    GINSBERG, ROSE; AND OTHERS

    FOURTEEN EFFORTS TO ORGANIZE AVAILABLE INFORMATION ON HUMAN LEARNING, TRANSFER, AND RETENTION ARE SUMMARIZED AND EVALUATED ON SIX CRITERIA--BEHAVIORAL SIGNIFICANCE OF CATEGORIES, SCOPE, OBJECTIVITY AND RELIABILITY OF CATEGORIES, PROGNOSIS FOR THE SYSTEM, LOGICAL STRUCTURE, AND HEURISTIC VALUE OF THE SYSTEM. ATTENTION IS GIVEN TO OTHER SOURCES OF…

  13. Effects of Learner Variables on Retention and Two Levels of Cognitive Material When Learning for Mastery.

    ERIC Educational Resources Information Center

    Riviere, Michael S.; Haladyna, Thomas H.

    Several tenets of mastery learning were examined in this study in the context of college level instruction. When students learn for mastery: (1) retention test scores should exhibit small variability and should be unrelated to aptitude; (2) test items which are classified into high and low cognitive behavior subscales should be unrelated to…

  14. Learning Skills Instruction Improves Student Retention and Academic Performance (ERIC/RCS).

    ERIC Educational Resources Information Center

    Johnson, David E.

    1989-01-01

    Examines the effectiveness of five college level learning skills centers on grade improvement and retention. Finds successful programs are well structured, link with academic courses students take concurrently, stress a supportive relationship with the instructor, include behavioral counseling, are interwoven with other services and programs, and…

  15. Impact of temperature during He+ implantation on deuterium retention in tungsten, tungsten with carbon deposit and tungsten carbide

    NASA Astrophysics Data System (ADS)

    Oya, Yasuhisa; Sato, Misaki; Li, Xiaochun; Yuyama, Kenta; Fujita, Hiroe; Sakurada, Shodai; Uemura, Yuki; Hatano, Yuji; Yoshida, Naoaki; Ashikawa, Naoko; Sagara, Akio; Chikada, Takumi

    2016-02-01

    Temperature dependence on deuterium (D) retention for He+ implanted tungsten (W) was studied by thermal desorption spectroscopy (TDS) to evaluate the tritium retention behavior in W. The activation energies were evaluated using Hydrogen Isotope Diffusion and Trapping (HIDT) simulation code and found to be 0.55 eV, 0.65 eV, 0.80 eV and 1.00 eV. The heating scenarios clearly control the D retention behavior and, dense and large He bubbles could work as a D diffusion barrier toward the bulk, leading to D retention enhancement at lower temperature of less than 430 K, even if the damage was introduced by He+ implantation. By comparing the D retention for W, W with carbon deposit and tungsten carbide (WC), the dense carbon layer on the surface enhances the dynamic re-emission of D as hydrocarbons, and induces the reduction of D retention. However, by He+ implantation, the D retention was increased for all the samples.

  16. 5 CFR 293.511 - Retention schedule.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... RECORDS Employee Medical File System Records § 293.511 Retention schedule. (a) Temporary EMFS records must... Administration (NARA). (b) Occupational Medical Records considered to be long-term records must be maintained...

  17. Taking a Holistic Approach to Retention.

    ERIC Educational Resources Information Center

    Fields, Cheryl D.

    2002-01-01

    Describes how, at the University of Kansas, many students of color are excelling at a rate that has outpaced their peers. Campus officials credit the HAWK Link program and its comprehensive approach to retention. (EV)

  18. 21 CFR 107.280 - Records retention.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN CONSUMPTION INFANT FORMULA Infant Formula Recalls § 107.280 Records retention. Each manufacturer... monitor recalls of the formula. Such records shall be retained for at least 1 year after the expiration...

  19. 21 CFR 107.280 - Records retention.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... HUMAN CONSUMPTION INFANT FORMULA Infant Formula Recalls § 107.280 Records retention. Each manufacturer... monitor recalls of the formula. Such records shall be retained for at least 1 year after the expiration...

  20. 21 CFR 107.280 - Records retention.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN CONSUMPTION INFANT FORMULA Infant Formula Recalls § 107.280 Records retention. Each manufacturer... monitor recalls of the formula. Such records shall be retained for at least 1 year after the expiration...

  1. 21 CFR 107.280 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... HUMAN CONSUMPTION INFANT FORMULA Infant Formula Recalls § 107.280 Records retention. Each manufacturer... monitor recalls of the formula. Such records shall be retained for at least 1 year after the expiration...

  2. Inconspicuous retention for removable partial dentures.

    PubMed

    King, G E; Barco, M T; Olson, R J

    1978-05-01

    Many dentists and patients believe that removable partial dentures have an unesthetic appearance when they replace anterior teeth because of the visible clasps. Two methods of obtaining inconspicuous retention have been described. PMID:349140

  3. Tritium retention and removal on TFTR

    SciTech Connect

    Mueller, D.; Blanchard, W.; Doyle, B.L.

    1997-11-01

    Tritium retention and removal are critical issues for the success of ITER or any DT fusion reactor. The Tokamak Fusion Test Reactor, TFTR, is the first fusion facility to afford the opportunity to study the tritium retention and removal over an extended period. In TFTR, tritium accumulates on all surfaces with line of sight to the plasma by codeposition of tritium with carbon. Measurements of both deuterium and tritium retention fractions have yielded retention between 0.2 and 0.6 of the injected fuel in the torus. Tritium has been successfully removed from TFTR by glow discharge cleaning and by air purges. The in-vessel inventory was reduced by a factor of 2, facilitating machine maintenance. In TFTR, the amount of dust recovered from the TFTR vacuum vessel has varied from several grams to a few kilograms.

  4. Tritium retention and removal on TFTR

    SciTech Connect

    Mueller, D.; Blanchard, W.; Doyle, B.L.

    1997-10-01

    Tritium retention and removal are critical issues for the success of ITER or any DT fusion reactor. The Tokamak Fusion Test Reactor, TFTR, is the first fusion facility to afford the opportunity to study the tritium retention and removal over an extended period. In TFTR, tritium accumulates on all surfaces with line of sight to the plasma by codeposition of tritium with carbon. Measurements of both deuterium and tritium retention fractions have yielded retention between 0.2 and 0.6 of the injected fuel in the torus. Tritium has been successfully removed from TFTR by glow discharge cleaning and by air purges. The in-vessel inventory was reduced by a factor of 2, facilitating machine maintenance. In TFTR, the amount of dust recovered from the TFTR vacuum vessel has varied from several grams to a few kilograms.

  5. Surface retention and photochemical reactivity of the diphenylether herbicide oxyfluorfen.

    PubMed

    Scrano, Laura; Bufo, Sabino A; Cataldi, Tommaso R I; Albanis, Triantafyllos A

    2004-01-01

    The photochemical behavior of oxyfluorfen [2-chloro-1-(3-etoxy-4-nitrophenoxy)-4-(trifluoromethyl) benzene] on two Greek soils was investigated. Soils were sampled from Nea Malgara and Preveza regions, characterized by a different organic matter content. Soils were spiked with the diphenyl-ether herbicide and irradiation experiments were performed either in the laboratory with a solar simulator (xenon lamp) or outside, under natural sunlight irradiation; other soil samples were kept in the dark to control the retention reaction. Kinetic parameters of both retention and photochemical reactions were calculated using zero-, first- and second- (Langmuir-Hinshelwood) order equations, and best fit was checked through statistical analysis. The soil behaviors were qualitatively similar but quantitatively different, with the soil sampled from the Nea Malgara region much more sorbent as compared with Preveza soil. All studied reactions followed second-order kinetics and photochemical reactions were influenced by retaining capability of the soils. The contributions of the photochemical processes to the global dissipation rates were also calculated. Two main metabolites were identified as 2-chloro-1-(3-ethoxy-4-hydroxyphenoxy)-4-(trifluoromethyl)benzene and 2-chloro-1- (3-hydroxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene. PMID:15074812

  6. Vecteurs Singuliers des Theories des Champs Conformes Minimales

    NASA Astrophysics Data System (ADS)

    Benoit, Louis

    En 1984 Belavin, Polyakov et Zamolodchikov revolutionnent la theorie des champs en explicitant une nouvelle gamme de theories, les theories quantiques des champs bidimensionnelles invariantes sous les transformations conformes. L'algebre des transformations conformes de l'espace-temps presente une caracteristique remarquable: en deux dimensions elle possede un nombre infini de generateurs. Cette propriete impose de telles conditions aux fonctions de correlations qu'il est possible de les evaluer sans aucune approximation. Les champs des theories conformes appartiennent a des representations de plus haut poids de l'algebre de Virasoro, une extension centrale de l'algebre conforme du plan. Ces representations sont etiquetees par h, le poids conforme de leur vecteur de plus haut poids, et par la charge centrale c, le facteur de l'extension centrale, commune a toutes les representations d'une meme theorie. Les theories conformes minimales sont constituees d'un nombre fini de representations. Parmi celles-ci se trouvent des theories unitaires dont les representation forment la serie discrete de l'algebre de Virasoro; leur poids h a la forme h_{p,q}(m)=[ (p(m+1) -qm)^2-1] (4m(m+1)), ou p,q et m sont des entiers positifs et p+q<= m+1. L'entier m parametrise la charge centrale: c(m)=1 -{6over m(m+1)} avec n>= 2. Ces representations possedent un sous-espace invariant engendre par deux sous-representations avec h_1=h_{p,q} + pq et h_2=h_{p,q} + (m-p)(m+1-q) dont chacun des vecteurs de plus haut poids portent le nom de vecteur singulier et sont notes respectivement |Psi _{p,q}> et |Psi_{m-p,m+1-q}>. . Les theories super-conformes sont une version super-symetrique des theories conformes. Leurs champs appartiennent a des representation de plus haut poids de l'algebre de Neveu-Schwarz, une des deux extensions super -symetriques de l'algebre de Virasoro. Les theories super -conformes minimales possedent la meme structure que les theories conformes minimales. Les representations

  7. Hydrogeomorphic controls on phosphorus retention in streams

    NASA Astrophysics Data System (ADS)

    Doyle, Martin W.; Stanley, Emily H.; Harbor, Jon M.

    2003-06-01

    We compared the relative influences of biochemical uptake processes and dynamic hydrology and geomorphology (hydrogeomorphology) on molybdate reactive phosphorus (MRP) retention within a stream. MRP concentrations were measured upstream and downstream of a 4.5-km reach undergoing dynamic channel adjustment in response to downstream dam removal. Geomorphic adjustments following removal produced measurable changes in velocity and depth, and decreases in MRP retention. Paired upstream and downstream measurements of MRP concentration were used to compute three retention metrics: uptake rate, mass transfer coefficient, and uptake length, which were used as model parameters. Modeling results showed that changes in channel morphology alone following dam removal could result in an approximate 40% increase in downstream MRP concentrations compared with conditions with the dam in place. However, empirical and modeling results indicate that hydrogeomorphology can control nutrient retention on the reach scale only when uptake processes are either sufficiently great or when uptake rates have limited variability. Review of published phosphorus retention values revealed greater variability in biochemical uptake rates than in hydrogeomorphology. Thus uptake rates should exert a stronger control on reach-scale MRP retention than changing channel morphology or hydrology. These results suggest that maintaining or restoring channel conditions that are conducive to biochemical uptake are of greater priority than restoration of hydrologic or geomorphic conditions alone.

  8. 5 CFR 536.302 - Optional pay retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Optional pay retention. 536.302 Section 536.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS GRADE AND PAY RETENTION Pay Retention § 536.302 Optional pay retention. (a) Subject to the requirements in §...

  9. 5 CFR 536.302 - Optional pay retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Optional pay retention. 536.302 Section 536.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS GRADE AND PAY RETENTION Pay Retention § 536.302 Optional pay retention. (a) Subject to the requirements in §...

  10. Retention in Care and Medication Adherence: Current Challenges to Antiretroviral Therapy Success

    PubMed Central

    Holtzman, Carol W.; Brady, Kathleen A.; Yehia, Baligh R.

    2015-01-01

    Health behaviors, such as retention in HIV medical care and adherence to antiretroviral therapy (ART), pose major challenges to reducing new HIV infections, addressing health disparities, and improving health outcomes. Andersen's Behavioral Model of Health Service Use provides a conceptual framework for understanding how patient and environmental factors affect health behaviors and outcomes, which can inform the design of intervention strategies. Factors affecting retention and adherence among persons with HIV include patient predisposing factors (e.g. mental illness, substance abuse), patient enabling factors (e.g. social support, reminder strategies, medication characteristics, transportation, housing, insurance), and health care environment factors (e.g. pharmacy services, clinic experiences, provider characteristics). Evidence-based recommendations for improving retention and adherence include 1) systematic monitoring of clinic attendance and ART adherence; 2) use of peer or paraprofessional navigators to re-engage patients in care and help them remain in care; 3) optimization of ART regimens and pharmaceutical supply chain management systems 4) provision of reminder devices and tools; 5) general education and counseling; 6) engagement of peer, family, and community support groups; 7) case management; and 8) targeting patients with substance abuse and mental illness. Further research is needed on effective monitoring strategies and interventions that focus on improving retention and adherence, with specific attention to the health care environment. PMID:25792300

  11. Retention in care and medication adherence: current challenges to antiretroviral therapy success.

    PubMed

    Holtzman, Carol W; Brady, Kathleen A; Yehia, Baligh R

    2015-04-01

    Health behaviors such as retention in HIV medical care and adherence to antiretroviral therapy (ART) pose major challenges to reducing new HIV infections, addressing health disparities, and improving health outcomes. Andersen's Behavioral Model of Health Service Use provides a conceptual framework for understanding how patient and environmental factors affect health behaviors and outcomes, which can inform the design of intervention strategies. Factors affecting retention and adherence among persons with HIV include patient predisposing factors (e.g., mental illness, substance abuse), patient-enabling factors (e.g., social support, reminder strategies, medication characteristics, transportation, housing, insurance), and healthcare environment factors (e.g., pharmacy services, clinic experiences, provider characteristics). Evidence-based recommendations for improving retention and adherence include (1) systematic monitoring of clinic attendance and ART adherence; (2) use of peer or paraprofessional navigators to re-engage patients in care and help them remain in care; (3) optimization of ART regimens and pharmaceutical supply chain management systems; (4) provision of reminder devices and tools; (5) general education and counseling; (6) engagement of peer, family, and community support groups; (7) case management; and (8) targeting patients with substance abuse and mental illness. Further research is needed on effective monitoring strategies and interventions that focus on improving retention and adherence, with specific attention to the healthcare environment. PMID:25792300

  12. Commitment to Student Retention: A Plan for Success. Final Report of the Retention Task Force.

    ERIC Educational Resources Information Center

    Lettman, Dennis

    A retention taskforce was established at Sinclair Community College (SCC) in Ohio to develop a plan to increase student retention. The 24-member taskforce, representing key areas within the college, worked for 15 months to prepare the plan. The plan was designed to be comprehensive, touching upon all points where the students interact with the…

  13. Retention through Intervention: A Strategic Plan for Retention of High-Risk Students.

    ERIC Educational Resources Information Center

    Mese, Janice H.; Spano, Carleen M.

    In an effort to increase the retention rates of high-risk students in allied health programs, the Medical Campus of Miami-Dade Community College has developed a strategic plan for retention that employs a systems approach to the integration of academic support services, emotional and social supports, and personalized communication. The assumptions…

  14. Considering Student Retention as a Complex System: A Possible Way forward for Enhancing Student Retention

    ERIC Educational Resources Information Center

    Forsman, Jonas; van den Bogaard, Maartje; Linder, Cedric; Fraser, Duncan

    2015-01-01

    This study uses multilayer minimum spanning tree analysis to develop a model for student retention from a complex system perspective, using data obtained from first-year engineering students at a large well-regarded institution in the European Union. The results show that the elements of the system of student retention are related to one another…

  15. Employee retention: a customer service approach.

    PubMed

    Gerson, Richard F

    2002-01-01

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

  16. Peste des petits ruminants

    PubMed Central

    Parida, S.; Muniraju, M.; Mahapatra, M.; Muthuchelvan, D.; Buczkowski, H.; Banyard, A.C.

    2015-01-01

    Peste des petits ruminants virus causes a highly infectious disease of small ruminants that is endemic across Africa, the Middle East and large regions of Asia. The virus is considered to be a major obstacle to the development of sustainable agriculture across the developing world and has recently been targeted by the World Organisation for Animal Health (OIE) and the Food and Agriculture Organisation (FAO) for eradication with the aim of global elimination of the disease by 2030. Fundamentally, the vaccines required to successfully achieve this goal are currently available, but the availability of novel vaccine preparations to also fulfill the requisite for differentiation between infected and vaccinated animals (DIVA) may reduce the time taken and the financial costs of serological surveillance in the later stages of any eradication campaign. Here, we overview what is currently known about the virus, with reference to its origin, updated global circulation, molecular evolution, diagnostic tools and vaccines currently available to combat the disease. Further, we comment on recent developments in our knowledge of various recombinant vaccines and on the potential for the development of novel multivalent vaccines for small ruminants. PMID:26443889

  17. Retention projection enables accurate calculation of liquid chromatographic retention times across labs and methods.

    PubMed

    Abate-Pella, Daniel; Freund, Dana M; Ma, Yan; Simón-Manso, Yamil; Hollender, Juliane; Broeckling, Corey D; Huhman, David V; Krokhin, Oleg V; Stoll, Dwight R; Hegeman, Adrian D; Kind, Tobias; Fiehn, Oliver; Schymanski, Emma L; Prenni, Jessica E; Sumner, Lloyd W; Boswell, Paul G

    2015-09-18

    Identification of small molecules by liquid chromatography-mass spectrometry (LC-MS) can be greatly improved if the chromatographic retention information is used along with mass spectral information to narrow down the lists of candidates. Linear retention indexing remains the standard for sharing retention data across labs, but it is unreliable because it cannot properly account for differences in the experimental conditions used by various labs, even when the differences are relatively small and unintentional. On the other hand, an approach called "retention projection" properly accounts for many intentional differences in experimental conditions, and when combined with a "back-calculation" methodology described recently, it also accounts for unintentional differences. In this study, the accuracy of this methodology is compared with linear retention indexing across eight different labs. When each lab ran a test mixture under a range of multi-segment gradients and flow rates they selected independently, retention projections averaged 22-fold more accurate for uncharged compounds because they properly accounted for these intentional differences, which were more pronounced in steep gradients. When each lab ran the test mixture under nominally the same conditions, which is the ideal situation to reproduce linear retention indices, retention projections still averaged 2-fold more accurate because they properly accounted for many unintentional differences between the LC systems. To the best of our knowledge, this is the most successful study to date aiming to calculate (or even just to reproduce) LC gradient retention across labs, and it is the only study in which retention was reliably calculated under various multi-segment gradients and flow rates chosen independently by labs. PMID:26292625

  18. Use of mucolytics to enhance magnetic particle retention at a model airway surface

    NASA Astrophysics Data System (ADS)

    Ally, Javed; Roa, Wilson; Amirfazli, A.

    A previous study has shown that retention of magnetic particles at a model airway surface requires prohibitively strong magnetic fields. As mucus viscoelasticity is the most significant factor contributing to clearance of magnetic particles from the airway surface, mucolytics are considered in this study to reduce mucus viscoelasticity and enable particle retention with moderate strength magnetic fields. The excised frog palate model was used to simulate the airway surface. Two mucolytics, N-acetylcysteine (NAC) and dextran sulfate (DS) were tested. NAC was found to enable retention at moderate field values (148 mT with a gradient of 10.2 T/m), whereas DS was found to be effective only for sufficiently large particle concentrations at the airway surface. The possible mechanisms for the observed behavior with different mucolytics are also discussed based on aggregate formation and the loading of cilia.

  19. Prediction of retention and identification of non-substituted polyaromatic hydrocarbons by liquid chromatography

    SciTech Connect

    Lanin, S.N.; Nikitin, Yu.S.

    1988-03-10

    Elucidation of the correlation between the structures of investigated compounds and their retention parameters in liquid chromatography allows one to predict their behavior in the chromatographic system and to choose optimal conditions of resolution, which is the main task. The important and complex problem remains analysis of waste water. Polycyclic aromatic hydrocarbons are among the most widespread and toxic pollutants of industrial waste and natural waters. Many of them are carcinogens. A correlation equation, universal for a certain class of substances, is proposed to describe the retention and separation of polyaromatic hydrocarbons by reversed phase liquid chromatography. The possibility was shown of its application to prediction of retention data for test substances and for their identification.

  20. Investigation of retention mechanism of resorcinarene based cavitands by linear and nonlinear chromatography.

    PubMed

    Bartó, Endre; Prauda, Ibolya; Kilár, Ferenc; Kiss, Ibolya; Felinger, Attila

    2016-07-22

    Cavitands are cavity-shaped cyclic oligomers and they can create host-guest interactions with various analytes, therefore they have applications in supramolecular chemistry, nanoscale reactions, chromatographic separations, drug encapsulation and delivery, biochemistry. The investigation of the chromatographic behavior of large molecules, such as resorcinarenes and cavitands is meager up to now. To understand the retention of resorcinarenes and cavitands in liquid chromatography, we studied their retention mechanism by the thermodynamic parameters calculated from the van't Hoff equation and by generation of an adsorption isotherm, which can describe the adsorption of the solute on the stationary phase surface. We compared the thermodynamics of the retention for cyclic oligomers in acetonitrile:water and methanol:water mobile phases. Furthermore, we determined the equilibrium adsorption isotherm by inverse method and we made an error analysis of the estimation obtained with the inverse method to ascertain the validity of the obtained isotherm parameters over a broader concentration range. PMID:27317005

  1. Combustion characteristics and arsenic retention during co-combustion of agricultural biomass and bituminous coal.

    PubMed

    Zhou, Chuncai; Liu, Guijian; Wang, Xudong; Qi, Cuicui; Hu, Yunhu

    2016-08-01

    A combination of thermogravimetric analysis (TG) and laboratory-scale circulated fluidized bed combustion experiment was conducted to investigate the thermochemical, kinetic and arsenic retention behavior during co-combustion bituminous coal with typical agricultural biomass. Results shown that ignition performance and thermal reactivity of coal could be enhanced by adding biomass in suitable proportion. Arsenic was enriched in fly ash and associated with fine particles during combustion of coal/biomass blends. The emission of arsenic decreased with increasing proportion of biomass in blends. The retention of arsenic may be attributed to the interaction between arsenic and fly ash components. The positive correlation between calcium content and arsenic concentration in ash suggesting that the arsenic-calcium interaction may be regarded as the primary mechanism for arsenic retention. PMID:27136608

  2. Critical role of surface roughness on colloid retention and release in porous media.

    PubMed

    Torkzaban, Saeed; Bradford, Scott A

    2016-01-01

    This paper examines the critical role of surface roughness (both nano- and micro-scale) on the processes of colloid retention and release in porous media under steady-state and transient chemical conditions. Nanoscale surface roughness (NSR) in the order of a few nanometers, which is common on natural solid surfaces, was incorporated into extended-DLVO calculations to quantify the magnitudes of interaction energy parameters (e.g. the energy barrier to attachment, ΔΦa , and detachment, ΔΦd , from a primary minimum). This information was subsequently used to explain the behavior of colloid retention and release in column and batch experiments under different ionic strength (IS) and pH conditions. Results demonstrated that the density and height of NSR significantly influenced the interaction energy parameters and consequently the extent and kinetics of colloid retention and release. In particular, values of ΔΦa and ΔΦd significantly decreased in the presence of NSR. Therefore, consistent with findings of column experiments, colloid retention in the primary minimum was predicted to occur at some specific locations on the sand surface, even at low IS conditions. However, NSR yielded a much weaker primary minimum interaction compared with that of smooth surfaces. Colloid release from primary minima upon decreasing IS and increasing pH was attributed to the impact of NSR on the values of ΔΦd . Pronounced differences in the amount of colloid retention in batch and column experiments indicated that primary minimum interactions were weak even at high IS conditions. Negligible colloid retention in batch experiments was attributed to hydrodynamic torques overcoming adhesive torques, whereas significant colloid retention in column experiments was attributed to nano- and micro-scale roughness which would dramatically alter the lever arms associated with hydrodynamic and adhesive torques. PMID:26512805

  3. A Practical Methodology to Measure Unbiased Gas Chromatographic Retention Factor vs. Temperature Relationships

    PubMed Central

    Peng, Baijie; Kuo, Mei-Yi; Yang, Panhia; Hewitt, Joshua T.; Boswell, Paul G.

    2014-01-01

    Compound identification continues to be a major challenge. Gas chromatography-mass spectrometry (GC-MS) is a primary tool used for this purpose, but the GC retention information it provides is underutilized because existing retention databases are experimentally restrictive and unreliable. A methodology called “retention projection” has the potential to overcome these limitations, but it requires the retention factor (k) vs. T relationship of a compound to calculate its retention time. Direct methods of measuring k vs. T relationships from a series of isothermal runs are tedious and time-consuming. Instead, a series of temperature programs can be used to quickly measure the k vs. T relationships, but they are generally not as accurate when measured this way because they are strongly biased by non-ideal behavior of the GC system in each of the runs. In this work, we overcome that problem by using the retention times of 25 n-alkanes to back-calculate the effective temperature profile and hold-up time vs. T profiles produced in each of six temperature programs. When the profiles were measured this way and taken into account, the k vs. T relationships measured from each of two different GC-MS instruments were nearly as accurate as the ones measured isothermally, showing less than 2-fold more error. Furthermore, temperature-programmed retention times calculated in five other labs from the new k vs. T relationships had the same distribution of error as when they were calculated from k vs. T relationships measured isothermally. Free software was developed to make the methodology easy to use. The new methodology potentially provides a relatively fast and easy way to measure unbiased k vs. T relationships. PMID:25496658

  4. Deuterium Retention in NSTX with Lithium Conditioning

    SciTech Connect

    C.H. Skinner, J.P. Allain, W. Blanchard, H.W. Kugel, R. Maingi, L. Roquemore, V. Soukhanovskii, C.N. Taylor

    2010-06-02

    High (≈ 90%) deuterium retention was observed in NSTX gas balance measurements both withand without lithiumization of the carbon plasma facing components. The gas retained in ohmic discharges was measured by comparing the vessel pressure rise after a discharge to that of a gasonly pulse with the pumping valves closed. For neutral beam heated discharges the gas input and gas pumped by the NB cryopanels were tracked. The discharges were followed by outgassing of deuterium that reduced the retention. The relationship between retention and surface chemistry was explored with a new plasma-material interface probe connected to an in-vacuo surface science station that exposed four material samples to the plasma. XPS and TDS analysis showed that the binding of D atoms is fundamentally changed by lithium - in particular atoms are weakly bonded in regions near lithium atoms bound to either oxygen or the carbon matrix.

  5. Safeguards Workforce Repatriation, Retention and Utilization

    SciTech Connect

    Gallucci, Nicholas; Poe, Sarah

    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.

  6. Retention of Hispanic/Latino students in first grade: Child, parent, teacher, school, and peer predictors.

    PubMed

    Willson, Victor L; Hughes, Jan N

    2006-02-01

    A sample of 283 Hispanic children with literacy performance at entrance to first grade below the median for their school district was studied as part of a larger research project on the predictors of grade retention in grade 1. Following retention decisions, 51 Hispanic students were retained in first grade. Low literacy skills, being young at entrance to first grade, low ego resilience, low support in the teacher-student relationship, and parents' low sense of responsibility for their children's educational outcomes predicted retention decisions. Hierarchical logistics regression investigated the contribution of six categories of variables (academic competencies; socio-demographic characteristics; social, emotional, and behavioral adjustment; resiliency, school context; and home environment) to retention. Controlling for literacy, only being young for grade and parents' low sense of responsibility for their children's adjustment to school made a direct contribution to retention. Early literacy skills were higher for children enrolled in bilingual classrooms than for children in non-bilingual classrooms. Implications for educational policy are discussed. PMID:20419036

  7. Retention of Hispanic/Latino students in first grade: Child, parent, teacher, school, and peer predictors

    PubMed Central

    Willson, Victor L.; Hughes, Jan N.

    2010-01-01

    A sample of 283 Hispanic children with literacy performance at entrance to first grade below the median for their school district was studied as part of a larger research project on the predictors of grade retention in grade 1. Following retention decisions, 51 Hispanic students were retained in first grade. Low literacy skills, being young at entrance to first grade, low ego resilience, low support in the teacher–student relationship, and parents’ low sense of responsibility for their children’s educational outcomes predicted retention decisions. Hierarchical logistics regression investigated the contribution of six categories of variables (academic competencies; socio-demographic characteristics; social, emotional, and behavioral adjustment; resiliency, school context; and home environment) to retention. Controlling for literacy, only being young for grade and parents’ low sense of responsibility for their children’s adjustment to school made a direct contribution to retention. Early literacy skills were higher for children enrolled in bilingual classrooms than for children in non-bilingual classrooms. Implications for educational policy are discussed. PMID:20419036

  8. Laparoscopic Treatment of Ovarian Retention Pathology

    PubMed

    Dionisi; Dionisi; Dionisi

    1996-08-01

    We define ovarian retention pathology as the complications (cystic, degenerative, adhesions, endometriosis, pain, etc.) attributed to ovaries deliberately retained at the time of hysterectomy. We established a protocol for laparoscopy in these women. During 14 laparoscopic procedures for ovarian retention pathology, only one intraoperative complication occurred, a small bowel injury requiring minilaparotomy. One woman required repeat surgery for ovarian remnant syndrome. Published experience with laparotomy suggests that significant injuries to or resections of bowel, bladder, or ureters can occur, but the limited experience with laparoscopic surgery has not shown significant complications. PMID:9074105

  9. Meningitis-retention Syndrome; A Case Report.

    PubMed

    Ishii, Gen; Hata, Kenichi; Aoki, Soichiro; Suzuki, Masayasu; Kimura, Takahiro; Egawa, Shin

    2016-05-01

    We report a case of meningitis-retention syndrome followed by urodynamic tests. A 48-year-old man was admitted to the hospital for an undiagnosed fever with headache and urinary retention. Aseptic meningitis was suspected according to cerebrospinal fluid analyses, and urodynamic test showed an underactive detrusor, leading to inadequate contraction of the bladder on voiding in spite of a normal sensation during bladder filling. Clean intermittent self-catheterization was required temporarily, but normal urinary voiding without the need for medication was restored in 2 weeks after discharge from the hospital, when urodynamic tests showed normal contractility of the bladder during voiding. PMID:27175342

  10. Meningitis-retention Syndrome; A Case Report

    PubMed Central

    Ishii, Gen; Hata, Kenichi; Aoki, Soichiro; Suzuki, Masayasu; Kimura, Takahiro; Egawa, Shin

    2016-01-01

    We report a case of meningitis-retention syndrome followed by urodynamic tests. A 48-year-old man was admitted to the hospital for an undiagnosed fever with headache and urinary retention. Aseptic meningitis was suspected according to cerebrospinal fluid analyses, and urodynamic test showed an underactive detrusor, leading to inadequate contraction of the bladder on voiding in spite of a normal sensation during bladder filling. Clean intermittent self-catheterization was required temporarily, but normal urinary voiding without the need for medication was restored in 2 weeks after discharge from the hospital, when urodynamic tests showed normal contractility of the bladder during voiding. PMID:27175342

  11. Nitrogen Saturation in Highly Retentive Watersheds?

    NASA Astrophysics Data System (ADS)

    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

  12. Modeling of Tritium Retention in TFTR

    SciTech Connect

    Blanchard, W.; Brooks, J.N.; Budny, R.V.; Hogan, J.T.; Hosea, J.; Skinner, C.H.; et al.

    1998-08-19

    The Tokamak Fusion Test Reactor (TFTR) tritium retention experience is reviewed and the data related to models of plasma surface interactions. Over 3.5 years of TFTR deuterium-tritium operations, approximately 51% of the tritium injected into TFTR was retained in the torus. Most of this was subsequently recovered by glow discharges and air ventilation. Co-deposition rates for representative conditions in tritium operation were modeled with the BBQ code. The calculations indicate that known erosion mechanisms and subsequent co-deposition are sufficient to account for the order of magnitude of retention.

  13. Effects of polymer retention on dynamics of single phase flow

    NASA Astrophysics Data System (ADS)

    Parsa, Shima; Weitz, David

    2014-11-01

    We study the effect of adsorption of polymer solution on dynamics of a single phase flow in a model porous medium. We use confocal microscopy to fully visualize the flow of fluid in 3D micromodel of porous media. Polymer flooding is known to be an effective method for enhanced oil recovery. However, the physical mechanism is not clearly understood. We study the effect of polymer retention on the dynamics of single phase flow using particle image velocimetery. The distribution of velocities in the medium changes greatly after flow of high concentrations of polymer through the medium. Comparing the magnitude of velocities before and after the polymer flow, we observe reduction of accessible pores to the fluid at similar injection rates. Independent measurement of the permeability of the medium confirms the decrease in the porosity. Measurements of the retention of polymer in porous media shows a weak dependence on the hydrodynamic radius of the polymer. In these experiments, the viscoelastic behavior of the polymer is isolated from velocity measurements.

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

    SciTech Connect

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

    2010-04-15

    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 {sup 125}I and 638 patients had {sup 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 alpha-blocker use (12.5% vs. 6.3%; p = 0.008), and increased prostate volume (13.4% vs. 6.9% vs. 2.9%, >45 cm{sup 3}, 25-45 cm{sup 3}, <25 cm{sup 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 alpha-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.

  15. Classification of 20 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Davis, T. M.; Kim, A. G.; Macualay, E.; Lidman, C.; Sharp, R.; Tucker, B. E.; Yuan, F.; Zhang, B.; Lewis, G. F.; Sommer, N. E.; Martini, P.; Mould, J.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  16. Classification of 15 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Yuan, F.; Tucker, B. E.; Lidman, C.; Martini, P.; Gshwend, Julia; Moller, A.; Zhang, B.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  17. Classification of 3 DES Supernovae with OzDES

    NASA Astrophysics Data System (ADS)

    Moller, A.; Tucker, B. E.; Yuan, F.; Lewis, G.; Lidman, C.; Macaulay, E.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.

    2016-02-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  18. Classification of 4 DES supernovae by OzDES

    NASA Astrophysics Data System (ADS)

    Glazebrook, K.; Amon, A.; Lidman, C.; Martini, P.; Tucker, B. E.; Yuan, F.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Pan, Y.-C.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.; Kessler, R.; Lasker, J.; Scolnic, D.; Brout, D. J.; Gladney, L.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; Childress, M.; D'Andrea, C.; Smith, M.; Sullivan, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.

    2015-12-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  19. Classification of 6 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Lewis, G. F.; Mould, J.; Lidman, C.; Tucker, B. E.; Sharp, R.; Yuan, F.; Martini, P.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Casas, R.; Castander, F. J.; Desai, S.; Paech, K.; Smith, R. C.; Schubnell, M.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey (ATEL #4668). The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  20. Classification of 14 DES Supernova with OzDES

    NASA Astrophysics Data System (ADS)

    Tucker, B. E.; Sharp, R.; Yuan, F.; Zhang, B.; Lidman, C.; Davis, T. M.; Hinton, S.; Mould, J.; Smith, R. C.; Schubnell, M.; Kessler, R.; Scolnic, D.; Covarrubias, R. A.; Brout, D. J.; Fischer, J. A.; Gladney, L.; March, M.; Sako, M.; Wolf, R. C.; Brown, P. J.; Krisciunas, K.; Suntzeff, N.; Nichol, R.; Papadopoulos, A.; D'Andrea, C.; Smith, M.; Sullivan, M.; Childress, M.; Maartens, R.; Gupta, R.; Kovacs, E.; Kuhlmann, S.; Spinka, H.; Ahn, E.; Finley, D. A.; Frieman, J.; Marriner, J.; Wester, W.; Aldering, G.; Kim, A. G.; Thomas, R. C.; Barbary, K.; Bloom, J. S.; Goldstein, D.; Nugent, P.; Perlmutter, S.; Foley, R. J.; Castander, F. J.; Desai, S.; Paech, K.

    2015-10-01

    We report new spectroscopic classifications by OzDES of supernovae discovered by the Dark Energy Survey. The spectra (370-885nm) were obtained with the AAOmega Spectrograph (Saunders et al. 2004, SPIE, 5492, 389) and the 2dF fibre positioner at the Anglo-Australian Telescope (AAT).

  1. Activation of the bacterial thermosensor DesK involves a serine zipper dimerization motif that is modulated by bilayer thickness.

    PubMed

    Cybulski, Larisa Estefanía; Ballering, Joost; Moussatova, Anastassiia; Inda, Maria Eugenia; Vazquez, Daniela B; Wassenaar, Tsjerk A; de Mendoza, Diego; Tieleman, D Peter; Killian, J Antoinette

    2015-05-19

    DesK is a bacterial thermosensor protein involved in maintaining membrane fluidity in response to changes in environmental temperature. Most likely, the protein is activated by changes in membrane thickness, but the molecular mechanism of sensing and signaling is still poorly understood. Here we aimed to elucidate the mode of action of DesK by studying the so-called "minimal sensor DesK" (MS-DesK), in which sensing and signaling are captured in a single transmembrane segment. This simplified version of the sensor allows investigation of membrane thickness-dependent protein-lipid interactions simply by using synthetic peptides, corresponding to the membrane-spanning parts of functional and nonfunctional mutants of MS-DesK incorporated in lipid bilayers with varying thicknesses. The lipid-dependent behavior of the peptides was investigated by circular dichroism, tryptophan fluorescence, and molecular modeling. These experiments were complemented with in vivo functional studies on MS-DesK mutants. Based on the results, we constructed a model that suggests a new mechanism for sensing in which the protein is present as a dimer and responds to an increase in bilayer thickness by membrane incorporation of a C-terminal hydrophilic motif. This results in exposure of three serines on the same side of the transmembrane helices of MS-DesK, triggering a switching of the dimerization interface to allow the formation of a serine zipper. The final result is activation of the kinase state of MS-DesK. PMID:25941408

  2. Attrition and Retention among Special Education Paraprofessionals

    ERIC Educational Resources Information Center

    Hall, Kimberly D.

    2009-01-01

    The purpose of the study was to obtain information about issues of turnover and retention among former and current special education paraprofessionals in one school district. Survey data and findings indicated ways to retain staff and reduce turnover. Information from this study was shared within the district and will be considered in creating…

  3. 5 CFR 9701.356 - Pay retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Pay retention. 9701.356 Section 9701.356 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN...

  4. Reframing Retention Strategy: A Focus on Process

    ERIC Educational Resources Information Center

    Schroeder, Charles C.

    2013-01-01

    When institutions engage in discussions regarding improving retention and graduation rates, invariably the conversation focuses on entering student characteristics, especially ACT and SAT scores and high school grades. Clearly, attracting and enrolling well-prepared and motivated high-ability students will certainly improve institutional measures…

  5. Relationship of Personality Traits to Student Retention

    ERIC Educational Resources Information Center

    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…

  6. Job Performance and Retention among Welfare Recipients.

    ERIC Educational Resources Information Center

    Holzer, Harry J.; Stoll, Michael A.; Wissoker, Douglas

    Data from interviews with 750 employers in Chicago, Cleveland, Milwaukee, and Los Angeles were used to analyze the job performance and retention rates of recently hired welfare recipients. The 20-minute interviews focused on employers' subjective ratings of recently hired welfare recipients' job performance and whether employers experienced the…

  7. Factors Contributing to Teacher Retention in Georgia

    ERIC Educational Resources Information Center

    Locklear, Tina M.

    2010-01-01

    The purpose of this mixed method, survey-based inquiry was to determine how Georgia public high school faculty members perceive various pressures and experiences associated with a career in education. These perceptions were then analyzed as possible indicators of teacher attrition in order to improve retention rates. The independent demographic…

  8. 1978-79 Recruitment & Retention Program.

    ERIC Educational Resources Information Center

    DeCosmo, Richard

    The Moraine Valley Community College (MVCC) 1978-79 Recruitment Program seeks to increase the pool of students who wish to attend college rather than compete more aggressively for those students who have already decided to participate in higher education. A special adjunct Retention Program has been developed to enhance the entire recruitment…

  9. 40 CFR 307.33 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 27 2010-07-01 2010-07-01 false Records retention. 307.33 Section 307.33 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SUPERFUND, EMERGENCY PLANNING, AND COMMUNITY RIGHT-TO-KNOW PROGRAMS COMPREHENSIVE ENVIRONMENTAL RESPONSE, COMPENSATION,...

  10. Student Retention in an Historically Black Institution.

    ERIC Educational Resources Information Center

    McDaniel, Cleve; Graham, Steven W.

    This study developed a statistical model to identify college students most prone to dropping out, testing the model to predict the retention status of black residential and white commuter students at an historically black institution with an open admissions policy. The model used 25 pre- and early-matriculation variables, including gender, age,…

  11. An Examination of Master's Student Retention & Completion

    ERIC Educational Resources Information Center

    Barry, Melissa; Mathies, Charles

    2011-01-01

    This study was conducted at a research-extensive public university in the southeastern United States. It examined the retention and completion of master's degree students across numerous disciplines. Results were derived from a series of descriptive statistics, T-tests, and a series of binary logistic regression models. The findings from binary…

  12. 10 CFR 490.810 - Record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Record retention. 490.810 Section 490.810 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490... documentation pertaining to its waiver application and alternative compliance, including petroleum...

  13. 49 CFR 236.1037 - Records retention.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Records retention. 236.1037 Section 236.1037 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND REPAIR OF SIGNAL AND...

  14. 7 CFR 1409.7 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AGRICULTURE GENERAL REGULATIONS AND POLICIES MEETINGS OF THE BOARD OF DIRECTORS OF COMMODITY CREDIT CORPORATION § 1409.7 Records retention. (a) The Secretary of the Board will maintain the following records for each Board meeting, or portion thereof which is closed to the public pursuant to a vote under §...

  15. 9 CFR 590.426 - Retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Retention. 590.426 Section 590.426 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Inspection,...

  16. 9 CFR 590.426 - Retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Retention. 590.426 Section 590.426 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Inspection,...

  17. 9 CFR 590.426 - Retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Retention. 590.426 Section 590.426 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Inspection,...

  18. 9 CFR 590.426 - Retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Retention. 590.426 Section 590.426 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Inspection,...

  19. 9 CFR 590.426 - Retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Retention. 590.426 Section 590.426 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE EGG PRODUCTS INSPECTION INSPECTION OF EGGS AND EGG PRODUCTS (EGG PRODUCTS INSPECTION ACT) Inspection,...

  20. Employee Retention: A Challenge of the Nineties.

    ERIC Educational Resources Information Center

    Zeiss, Tony

    1990-01-01

    Considers ways in which community colleges can help employers implement programs to improve the work environment and retain trained workers. Presents a model for employee retention that has worked effectively in Pueblo, Colorado. Describes Pueblo Community College's cooperative program with the Wats Marketing Group to help reduce employee…

  1. Shaping Retention from Research to Practice

    ERIC Educational Resources Information Center

    Braxton, John M.; Brier, Ellen M.; Steele, Stephanie Lee

    2008-01-01

    This article presents seven guidelines to direct professional practice aimed toward the improvement of institutional student retention rates. For each of the seven guidelines, specific recommendations to provide direction to the enactment of the focal guideline are described. These seven guidelines spring from empirical studies of campus-based…

  2. Healthcare Learning Community and Student Retention

    ERIC Educational Resources Information Center

    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…

  3. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 9 Animals and Animal Products 2 2013-01-01 2013-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION VOLUNTARY INSPECTION OF...

  4. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION VOLUNTARY INSPECTION OF...

  5. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 9 Animals and Animal Products 2 2014-01-01 2014-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION VOLUNTARY INSPECTION OF...

  6. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION VOLUNTARY INSPECTION OF...

  7. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY ORGANIZATION AND TERMINOLOGY; MANDATORY MEAT AND POULTRY PRODUCTS INSPECTION AND VOLUNTARY INSPECTION AND CERTIFICATION VOLUNTARY INSPECTION OF...

  8. 78 FR 57927 - Credit Risk Retention

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-20

    ... proposal, as described in more detail below. \\5\\ Credit Risk Retention; Proposed Rule, 76 FR 24090 (April... legislation.''). \\24\\ See 78 FR 6408 (January 30, 2013), as amended by 78 FR 35430 (June 12, 2013). These two... Federal Register. See 76 FR 27390 (May 11, 2011). The Board had initial responsibility for...

  9. 5 CFR 9701.356 - Pay retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM Pay and Pay Administration Pay Administration § 9701.356 Pay retention. (a) Subject to...

  10. 5 CFR 9701.356 - Pay retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM Pay and Pay Administration Pay Administration § 9701.356 Pay retention. (a) Subject to...

  11. 5 CFR 9701.356 - Pay retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM Pay and Pay Administration Pay Administration § 9701.356 Pay retention. (a) Subject to...

  12. 40 CFR 35.6705 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... concerning Federal Government records (36 CFR parts 1220 through 1234) and EPA records management... the starting dates for records retention described in 40 CFR 31.42(c) (1) and (2). ... been started before the expiration of the ten-year period, the records must be retained...

  13. 40 CFR 35.6705 - Records retention.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... concerning Federal Government records (36 CFR parts 1220 through 1234) and EPA records management... the starting dates for records retention described in 40 CFR 31.42(c) (1) and (2). ... been started before the expiration of the ten-year period, the records must be retained...

  14. 7 CFR 275.4 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Record retention. 275.4 Section 275.4 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Administration § 275.4...

  15. 19 CFR 10.308 - Records retention.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Records retention. 10.308 Section 10.308 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Canada Free Trade Agreement §...

  16. 19 CFR 10.308 - Records retention.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Records retention. 10.308 Section 10.308 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Canada Free Trade Agreement §...

  17. Sediment retention in rangeland riparian buffers.

    PubMed

    Hook, Paul B

    2003-01-01

    Controlling nonpoint-source sediment pollution is a common goal of riparian management, but there is little quantitative information about factors affecting performance of rangeland riparian buffers. This study evaluated the influence of vegetation characteristics, buffer width, slope, and stubble height on sediment retention in a Montana foothills meadow. Three vegetation types (sedge wetland, rush transition, bunchgrass upland) were compared using twenty-six 6- x 2-m plots spanning 2 to 20% slopes. Plots were clipped moderately (10-15 cm stubble) or severely (2-5 cm stubble). Sediment (silt + fine sand) was added to simulated overland runoff 6, 2, or 1 m above the bottom of each plot. Runoff was sampled at 15-s to > 5-min intervals until sediment concentrations approached background levels. Sediment retention was affected strongly by buffer width and moderately by vegetation type and slope, but was not affected by stubble height. Mean sediment retention ranged from 63 to > 99% for different combinations of buffer width and vegetation type, with 94 to 99% retention in 6-m-wide buffers regardless of vegetation type or slope. Results suggest that rangeland riparian buffers should be at least 6 m wide, with dense vegetation, to be effective and reliable. Narrower widths, steep slopes, and sparse vegetation increase risk of sediment delivery to streams. Vegetation characteristics such as biomass, cover, or density are more appropriate than stubble height for judging capacity to remove sediment from overland runoff, though stubble height may indirectly indicate livestock impacts that can affect buffer performance. PMID:12809315

  18. 24 CFR 266.515 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 24 Housing and Urban Development 2 2011-04-01 2011-04-01 false Record retention. 266.515 Section 266.515 Housing and Urban Development Regulations Relating to Housing and Urban Development (Continued) OFFICE OF ASSISTANT SECRETARY FOR HOUSING-FEDERAL HOUSING COMMISSIONER, DEPARTMENT OF HOUSING AND...

  19. 76 FR 34010 - Credit Risk Retention

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-10

    ..., 2011, at 76 FR 24090, is extended. Comments on the Credit Risk NPR must be received on or before August... 76 FR 24090. The Credit Risk NPR would specify credit risk retention requirements for securitizers of... Office of the Comptroller of the Currency 12 CFR Part 43 RIN 1557-AD40 FEDERAL RESERVE SYSTEM 12 CFR...

  20. 10 CFR 490.810 - Record retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Record retention. 490.810 Section 490.810 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490... documentation pertaining to its waiver application and alternative compliance, including petroleum...

  1. 10 CFR 490.810 - Record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Record retention. 490.810 Section 490.810 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490... documentation pertaining to its waiver application and alternative compliance, including petroleum...

  2. 10 CFR 490.810 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Record retention. 490.810 Section 490.810 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490... documentation pertaining to its waiver application and alternative compliance, including petroleum...

  3. 10 CFR 490.810 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Record retention. 490.810 Section 490.810 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ALTERNATIVE FUEL TRANSPORTATION PROGRAM Alternative Compliance § 490... documentation pertaining to its waiver application and alternative compliance, including petroleum...

  4. Effects of Emotional Intelligence on Teacher Retention

    ERIC Educational Resources Information Center

    Gerald, Grant Ronald

    2010-01-01

    This mixed methods, explanatory design study focused on determining if the emotional intelligence of principals affects the retention of new teachers. In phase one, a non-random cluster sample of 138 public school principals in the state of Louisiana was surveyed using a quantitative instrument. A Factor Analysis, Analysis of Variance (ANOVA), and…

  5. Managing Retention under the New Skills Agenda.

    ERIC Educational Resources Information Center

    Hemsley-Brown, Jane

    2002-01-01

    Within the context of funding changes in further education, a British study of three training providers with successful retention programs found that two further education colleges were more successful than an industry provider. Key factors in reducing student withdrawal included support and guidance services for trainees, delivery of key skills,…

  6. Retention of Electronic Fundamentals: Differences Among Topics.

    ERIC Educational Resources Information Center

    Johnson, Kirk A.

    Criterion-referenced tests were used to measure the learning and retention of a sample of material taught by means of programed instruction in the Avionics Fundamentals Course, Class A. It was found that the students knew about 30 percent of the material before reading the programs, that mastery rose to a very high level on the immediate posttest,…

  7. Does Grade Retention Make a Difference?

    ERIC Educational Resources Information Center

    Tingle, Lynne R.; Schoeneberger, Jason; Algozzine, Bob

    2012-01-01

    Despite a continuing record of interest over the years, few studies have documented the demographics of grade retention or the relationship between it and academic achievement across multiple grades and groups of students. In this research, we were interested in the characteristics and consequences of retaining students in elementary (K-5) and…

  8. 5 CFR 9701.356 - Pay retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 3 2010-01-01 2010-01-01 false Pay retention. 9701.356 Section 9701.356 Administrative Personnel DEPARTMENT OF HOMELAND SECURITY HUMAN RESOURCES MANAGEMENT SYSTEM (DEPARTMENT OF HOMELAND SECURITY-OFFICE OF PERSONNEL MANAGEMENT) DEPARTMENT OF HOMELAND SECURITY HUMAN...

  9. 33 CFR 133.21 - Records retention.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Records retention. 133.21 Section 133.21 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS §...

  10. 33 CFR 133.21 - Records retention.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Records retention. 133.21 Section 133.21 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS §...

  11. 33 CFR 133.21 - Records retention.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Records retention. 133.21 Section 133.21 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS §...

  12. 33 CFR 133.21 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Records retention. 133.21 Section 133.21 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS §...

  13. 33 CFR 133.21 - Records retention.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Records retention. 133.21 Section 133.21 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION OIL SPILL LIABILITY TRUST FUND; STATE ACCESS §...

  14. Metals Retention in Constructed Wetland Sediments

    SciTech Connect

    KNOX, ANNA

    2004-10-27

    The A-01 wetland treatment system (WTS) was designed to remove metals from the effluent at the A-01 NPDES outfall at the Savannah River Site, Aiken, SC. Sequential extraction data was used to evaluate remobilization and retention of Cu, Pb, Zn, Mn, and Fe in the wetland sediment. Remobilization of metals was determined by the Potentially Mobile Fraction (PMF) and metal retention by the Recalcitrant Factor (RF). The PMF, which includes water soluble, exchangeable, and oxides fractions, is the contaminant fraction that has the potential to enter into the mobile aqueous phase under changeable environmental conditions. PMF values were low for Cu, Zn and Pb (about 20 percent) and high for Fe and Mn (about 60 to 70 percent). The RF, which includes crystalline oxides, sulfides or silicates and aluminosilicates, is the ratio of strongly bound fractions to the total concentration of elements in sediment. RF values were about 80 percent for Cu, Zn and Pb, indicating high retention in the sediment and 30 percent to above 40 percent for Fe and Mn indication low retention.

  15. Personnel Recruitment and Retention in Rural America.

    ERIC Educational Resources Information Center

    Helge, Doris; Marrs, Lawrence W.

    Recruitment and retention of special education teachers and related services staff have been persistent problems of rural school districts nationwide. High teacher attrition rates have serious ramifications for personnel development and program stability. Effective recruitment strategies for rural areas have four main components: (1) emphasis on…

  16. Does Retention Help? Perspectives after Three Years.

    ERIC Educational Resources Information Center

    Schuyler, Nancy Baenen

    The Austin Independent School District Office of Research and Evaluation (AISD-ORE) has recently completed a three year study of the effects of retention on elementary students. As in other studies comparing the academic achievement of elementary retainees and similar students not retained, findings indicated that promoted students generally show…

  17. Tallahassee Community College Retention Study. Final Report.

    ERIC Educational Resources Information Center

    Johnston, Archie B.

    A retention study was conducted at Tallahassee Community College (TCC) to determine reasons student withdrew from TCC prior to meeting their educational objectives. The survey population consisted of all students, apart from graduates and those who had been academically suspended, who were enrolled in winter 1981 but had not returned by winter…

  18. Testing to Enhance Retention in Human Anatomy

    ERIC Educational Resources Information Center

    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…

  19. 40 CFR 35.6705 - Records retention.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... the starting dates for records retention described in 40 CFR 31.42(c) (1) and (2). ... been started before the expiration of the ten-year period, the records must be retained until completion of the action and resolution of all issues which arise from it, or until the end of the...

  20. 40 CFR 35.6705 - Records retention.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... the starting dates for records retention described in 40 CFR 31.42(c) (1) and (2). ... been started before the expiration of the ten-year period, the records must be retained until completion of the action and resolution of all issues which arise from it, or until the end of the...

  1. Return on Investment: Libraries and Student Retention

    ERIC Educational Resources Information Center

    Mezick, Elizabeth M.

    2007-01-01

    Using data on libraries collected by the Association of Research Libraries (ARL) and the Association of College and Research Libraries (ACRL), as well as fall-to-fall retention rates obtained from the Integrated Postsecondary Education Data System (IPEDS) of the National Center for Education Statistics (NCES), this study employs statistical…

  2. High temperature ceramic composition for hydrogen retention

    DOEpatents

    Webb, R.W.

    1974-01-01

    A ceramic coating for H retention in fuel elements is described. The coating has relatively low thermal neutron cross section, is not readily reduced by H at 1500 deg F, is adherent to the fuel element base metal, and is stable at reactor operating temperatures. (JRD)

  3. 7 CFR 275.4 - Record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Record retention. 275.4 Section 275.4 Agriculture... FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Administration § 275.4 Record... Schedule other materials supporting the review decision; sample lists; sampling frames; tabulation...

  4. 7 CFR 275.4 - Record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 4 2012-01-01 2012-01-01 false Record retention. 275.4 Section 275.4 Agriculture... FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Administration § 275.4 Record... Schedule; other materials supporting the review decision; sample lists; sampling frames; tabulation...

  5. 7 CFR 275.4 - Record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Record retention. 275.4 Section 275.4 Agriculture... FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Administration § 275.4 Record... Schedule; other materials supporting the review decision; sample lists; sampling frames; tabulation...

  6. 7 CFR 275.4 - Record retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... FOOD STAMP AND FOOD DISTRIBUTION PROGRAM PERFORMANCE REPORTING SYSTEM Administration § 275.4 Record retention. (a) The State agency shall maintain Performance Reporting System records to permit ready access to, and use of, these records. Performance Reporting System records include information used in...

  7. Retention of First Year Community College Students

    ERIC Educational Resources Information Center

    Windham, Melissa H.

    2012-01-01

    Although close to half of all community college students leave before obtaining their stated goals, most retention studies are still being conducted at the four-year college and university level. There is still little research conducted at the community college level. In order to determine what student characteristics increase community college…

  8. Recruitment and Retention with a Spin

    ERIC Educational Resources Information Center

    Lindgren, Rita; Hixson, Carla Braun

    2010-01-01

    Strategic planning and innovation at Bismarck State College (BSC) found common ground in the college's goal to recruit and retain employees in an environment of low unemployment and strong competition for skilled employees. BSC's strategic plan for 2007-09 included the objective "to increase retention of employees." One of the strategies connected…

  9. 19 CFR 10.308 - Records retention.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Records retention. 10.308 Section 10.308 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Canada Free Trade Agreement §...

  10. Structural Information Retention in Visual Art Processing.

    ERIC Educational Resources Information Center

    Koroscik, Judith Smith

    The accuracy of non-art college students' longterm retention of structural information presented in Leonardo da Vinci's "Mona Lisa" was tested. Seventeen female undergraduates viewed reproductions of the painting and copies that closely resembled structural attributes of the original. Only 3 of the 17 subjects reported having viewed a reproduction…

  11. COMPARTMENTAL MODEL OF NITRATE RETENTION IN STREAMS

    EPA Science Inventory

    A compartmental modeling approach is presented to route nitrate retention along a cascade of stream reach sections. A process transfer function is used for transient storage equations with first order reaction terms to represent nitrate uptake in the free stream, and denitrifica...

  12. Plastic debris retention and exportation by a mangrove forest patch.

    PubMed

    Ivar do Sul, Juliana A; Costa, Monica F; Silva-Cavalcanti, Jacqueline S; Araújo, Maria Christina B

    2014-01-15

    An experiment observed the behavior of selected tagged plastic items deliberately released in different habitats of a tropical mangrove forest in NE Brazil in late rainy (September) and late dry (March) seasons. Significant differences were not reported among seasons. However, marine debris retention varied among habitats, according to characteristics such as hydrodynamic (i.e., flow rates and volume transported) and relative vegetation (Rhizophora mangle) height and density. The highest grounds retained significantly more items when compared to the borders of the river and the tidal creek. Among the used tagged items, PET bottles were more observed and margarine tubs were less observed, being easily transported to adjacent habitats. Plastic bags were the items most retained near the releasing site. The balance between items retained and items lost was positive, demonstrating that mangrove forests tend to retain plastic marine debris for long periods (months-years). PMID:24321881

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

    PubMed

    Tynelius, Gudrun Edman

    2014-01-01

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

  14. Transport and retention of multi-walled carbon nanotubes in saturated porous media: effects of input concentration and grain size.

    PubMed

    Kasel, Daniela; Bradford, Scott A; Šimůnek, Jiří; Heggen, Marc; Vereecken, Harry; Klumpp, Erwin

    2013-02-01

    Water-saturated column experiments were conducted to investigate the effect of input concentration (C₀) and sand grain size on the transport and retention of low concentrations (1, 0.01, and 0.005 mg L⁻¹) of functionalized ¹⁴C-labeled multi-walled carbon nanotubes (MWCNT) under repulsive electrostatic conditions that were unfavorable for attachment. The breakthrough curves (BTCs) for MWCNT typically did not reach a plateau, but had an asymmetric shape that slowly increased during breakthrough. The retention profiles (RPs) were not exponential with distance, but rather exhibited a hyper-exponential shape with greater retention near the column inlet. The collected BTCs and RPs were simulated using a numerical model that accounted for both time- and depth-dependent blocking functions on the retention coefficient. For a given C₀, the depth-dependent retention coefficient and the maximum solid phase concentration of MWCNT were both found to increase with decreasing grain size. These trends reflect greater MWCNT retention rates and a greater number of retention locations in the finer textured sand. The fraction of the injected MWCNT mass that was recovered in the effluent increased and the RPs became less hyper-exponential in shape with higher C₀ due to enhanced blocking/filling of retention locations. This concentration dependency of MWCNT transport increased with smaller grain size because of the effect of pore structure and MWCNT shape on MWCNT retention. In particular, MWCNT have a high aspect ratio and we hypothesize that solid phase MWCNT may create a porous network with enhanced ability to retain particles in smaller grain sized sand, especially at higher C₀. Results demonstrate that model simulations of MWCNT transport and fate need to accurately account for observed behavior of both BTCs and RPs. PMID:23228890

  15. Reliability of in-stream retention metrics

    NASA Astrophysics Data System (ADS)

    Savickis, Jevgenijs; Zaramella, Mattia; Marion, Andrea

    2016-04-01

    The temporary solute retention within transient storage zones (TSZs) has been shown to have a large effect on the transport of solute. This retention can significantly increase the overall in-stream residence time and as consequence increase the contact time of solute with aquatic interfaces (biota, sediment) and living species. An important question that arises is whether the currently available metrics adequately represent retention mechanism. This work attempts to investigate the reliability of two existing measures, the hydrological retention factor (Rh) and the fraction of median travel time due to transient storage zone (Fmed200). For this purpose, five conservative tracer tests were conducted in four European streams with distinct morphological, sediment composition, vegetation and hydraulic characteristics. The obtained breakthrough curves (BTCs) were used to derive storage zone parameters (storage zone area, storage zone exchange coefficient and mean residence time), which then were used for comparison and in the metric expressions. The storage zone parameters were computed using a single TSZ model OTIS-P and a multiple TSZ model STIR. The STIR model was applied to BTCs as an additional tool to separate TSZs into short timescale (ST) and long timescale (LT). The study results reveal correlation between Fmed200 and LT residence time T2 values, where the streams with the lowest Fmed200 (0.01-0.96) have the smallest long timescale storage zones T2 values, ranging from 912 s to 1402 s. The findings also demonstrate an influence of discharge rate on both retention metrics. The greatest Fmed200 (6.19) and Rh (0.938) values are calculated for the streams with low discharge rates (0.08-0.10 m3s‑1) and a relatively high ST storage zone residence times T1 (159 s to 351 s). Results show that the Fmed200 and Rh metrics are strongly affected by the short timescale transient storage zones, whereas the LT storage zones (hyporheic) effects are not taken into account.

  16. 34 CFR 686.38 - Maintenance and retention of records.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (TEACH) GRANT PROGRAM Administration of Grant Payments § 686.38 Maintenance and retention of records. (a) An institution must follow the record retention and examination provisions in this part and in 34...

  17. Blister formation and deuterium retention on tungsten exposed to low energy and high flux deuterium plasma

    NASA Astrophysics Data System (ADS)

    Tokunaga, K.; Baldwin, M. J.; Doerner, R. P.; Noda, N.; Kubota, Y.; Yoshida, N.; Sogabe, T.; Kato, T.; Schedler, B.

    2005-03-01

    Deuterium ion irradiation on tungsten has been carried out with incident energies of 100 eV and flux of 1 × 10 22 D + m -2 s -1 at a temperature in range between 333 K and 1130 K up to a dose of 1 × 10 26 D + m -2. Three kinds of tungsten used are pure tungsten made by powder metallurgy tungsten (PM-W), vacuum plasma spray tungsten (VPS-W) and single crystal tungsten (SC-W). Surface morphology before and after the irradiation is observed with an SEM. In addition, retention property of deuterium after the irradiation is also examined with a TDS. Behavior of blister formation depends on the kind of the samples and the irradiation temperatures. TDS measurement also shows that deuterium is not retained in sample, which the blisters are not formed. The behavior of the blister formation and deuterium retention is influenced by the manufacturing process and the sample history of tungsten.

  18. The Tennessee Lottery Scholarship Program: Impact on Retention

    ERIC Educational Resources Information Center

    Puryear, Carol G.

    2009-01-01

    This study examined if the Tennessee Education Lottery Scholarship (TELS), which began in 2004, was related to student retention at the six Tennessee Board of Regents four-year institutions. This study investigated the impact of the TELS on student retention at TBR universities and general knowledge regarding retention. Post-facto data were…

  19. Grade Retention: What are the Costs and Benefits?

    ERIC Educational Resources Information Center

    Eide, Eric R.; Goldhaber, Dan D.

    2005-01-01

    Grade retention is a common practice used when students fail to meet required benchmarks. Therefore, it is important that we understand the relative benefits and costs associated with students repeating a grade. In this article we analyze the costs and benefits of grade retention. In our examination of retention, we obtain our calculations of the…

  20. Framing Retention for Institutional Improvement: A 4 Ps Framework

    ERIC Educational Resources Information Center

    Kalsbeek, David H.

    2013-01-01

    A 4 Ps framework for student retention strategy is a construct for reframing the retention discussion in a way that enables institutional improvement by challenging some conventional wisdom and prevailing perspectives that have characterized retention strategy for years. It opens new possibilities for action and improvement by suggesting that…

  1. 12 CFR Appendix A to Part 749 - Record Retention Guidelines

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Record Retention Guidelines A Appendix A to... RECORDS PRESERVATION PROGRAM AND APPENDICES-RECORD RETENTION GUIDELINES; CATASTROPHIC ACT PREPAREDNESS GUIDELINES Pt. 749, App. A Appendix A to Part 749—Record Retention Guidelines Credit unions often look...

  2. 12 CFR Appendix A to Part 749 - Record Retention Guidelines

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Record Retention Guidelines A Appendix A to... RECORDS PRESERVATION PROGRAM AND APPENDICES-RECORD RETENTION GUIDELINES; CATASTROPHIC ACT PREPAREDNESS GUIDELINES Pt. 749, App. A Appendix A to Part 749—Record Retention Guidelines Credit unions often look...

  3. Measuring Student Retention at an Online Institution of Higher Education

    ERIC Educational Resources Information Center

    Boston, Wallace E., Jr.

    2010-01-01

    Student persistence or retention has been a documented issue in higher education in the United States since the late 1800s. While much has been written about the topic of retention at the more traditional types of institutions, little has been written about retention at the online institutions of higher learning that have developed since the early…

  4. 21 CFR 58.195 - Retention of records.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Retention of records. 58.195 Section 58.195 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL GOOD LABORATORY PRACTICE FOR NONCLINICAL LABORATORY STUDIES Records and Reports § 58.195 Retention of records. (a) Record retention requirements set forth in...

  5. 48 CFR 4.704 - Calculation of retention periods.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Calculation of retention periods. 4.704 Section 4.704 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION GENERAL ADMINISTRATIVE MATTERS Contractor Records Retention 4.704 Calculation of retention periods. (a) The...

  6. 5 CFR 317.801 - Retention of SES provisions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Retention of SES provisions. 317.801... EMPLOYMENT IN THE SENIOR EXECUTIVE SERVICE Retention of SES Provisions § 317.801 Retention of SES provisions. (a) Coverage. This subpart applies to— (1) A career appointee in the SES appointed at any time by...

  7. Retention Initiatives Used by Professional Master's Athletic Training Program Directors

    ERIC Educational Resources Information Center

    Bowman, Thomas G.; Dodge, Thomas M.; Mazerolle, Stephanie M.

    2015-01-01

    Context: Many professional master's athletic training program directors believe retention is a problem facing athletic training education. However, it remains unknown what steps, if any, are taken to improve retention. Objective: To inquire with program directors about their respective methods and interventions aimed at increasing retention rates.…

  8. Influence of helium on deuterium retention in reduced activation ferritic martensitic steel (F82H) under simultaneous deuterium and helium irradiation

    NASA Astrophysics Data System (ADS)

    Yakushiji, K.; Lee, H. T.; Oya, M.; Hamaji, Y.; Ibano, K.; Ueda, Y.

    2016-02-01

    Deuterium and helium retention in Japanese reduced activation ferritic martensitic (RAFM) steel (F82H) under simultaneous D-He irradiation at 500, 625, 750, and 818 K was studied. This study aims to clarify tritium retention behavior in RAFM steels to assess their use as plasma facing materials. The irradiation fluence was kept constant at 1 × 1024 D m-2. Four He desorption peaks were observed with He retention greatest at 625 K. At T > 625 K a monotonic decrease in He retention was observed. At all temperatures a systematic reduction in D retention was observed for the simultaneous D-He case in comparison to D-only case. This suggests that He implanted at the near surface in RAFM steels may reduce the inward penetration of tritium in RAFM steels that would result in lower tritium inventory for a given fluence.

  9. The Influence of Movement Initiation Deficits on the Quantification of Retention in Parkinson’s Disease

    PubMed Central

    Pendt, Lisa K.; Maurer, Heiko; Müller, Hermann

    2012-01-01

    In patients with an impaired motor system, like Parkinson’s disease (PD), deficits in motor learning are expected and results of various studies seem to confirm these expectations. However, most studies in this regard are behaviorally based and quantify learning by performance changes between at least two points in time, e.g., baseline and retention. But, performance in a retention test is also dependent on other factors than learning. Especially in patients, the functional capacity of the control system might be altered unspecific to a certain task and learning episode. The aim of the study is to test whether characteristic temporal deficits exist in PD patients that affect retention performance. We tested the confounding effects of typical PD motor control deficits, here movement initiation deficits, on retention performance in the motor learning process. 12 PD patients and 16 healthy control participants practiced a virtual throwing task over 3 days with 24 h rest between sessions. Retention was tested comparing performance before rest with performance after rest. Movement initiation deficits were quantified by the timing of throwing release that should be affected by impairments in movement initiation. To scrutinize the influence of the initiation deficits on retention performance we gave participants a specific initiation intervention prior to practice on one of the three practice days. We found that only for the PD patients, post-rest performance as well as release timing was better with intervention as compared to without intervention. Their performance could be enhanced through a tuning of release initiation. Thus, we suggest that in PD patients, performance decline after rest that might be easily interpreted as learning deficits could rather result from disease-related deficiencies in motor control. PMID:22870067

  10. Strategies to improve retention in randomised trials

    PubMed Central

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

    2013-01-01

    Background Loss to follow-up from randomised trials can introduce bias and reduce study power, affecting the generalisability, validity and reliability of results. Many strategies are used to reduce loss to follow-up and improve retention but few have been formally evaluated. Objectives To quantify the effect of strategies to improve retention on the proportion of participants retained in randomised trials and to investigate if the effect varied by trial strategy and trial setting. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PreMEDLINE, EMBASE, PsycINFO, DARE, CINAHL, Campbell Collaboration's Social, Psychological, Educational and Criminological Trials Register, and ERIC. We handsearched conference proceedings and publication reference lists for eligible retention trials. We also surveyed all UK Clinical Trials Units to identify further studies. Selection criteria We included eligible retention trials of randomised or quasi-randomised evaluations of strategies to increase retention that were embedded in 'host' randomised trials from all disease areas and healthcare settings. We excluded studies aiming to increase treatment compliance. Data collection and analysis We contacted authors to supplement or confirm data that we had extracted. For retention trials, we recorded data on the method of randomisation, type of strategy evaluated, comparator, primary outcome, planned sample size, numbers randomised and numbers retained. We used risk ratios (RR) to evaluate the effectiveness of the addition of strategies to improve retention. We assessed heterogeneity between trials using the Chi2 and I2 statistics. For main trials that hosted retention trials, we extracted data on disease area, intervention, population, healthcare setting, sequence generation and allocation concealment. Main results We identified 38 eligible retention trials. Included trials evaluated six broad types of strategies to improve retention. These

  11. Tritium Retention and Removal in Tokamaks

    SciTech Connect

    Skinner, Charles H.

    2009-02-19

    Management of tritium inventory remains one of the grand challenges in the development of fusion energy. Tritium is an important source term in safety assessments, it is expensive and in short supply. Tritium can be continuously retained in a tokamak by codeposition with eroded carbon or beryllium and JET and TFTR with carbon plasma facing components showed a tritium retention level that would be unacceptable in ITER or future fusion reactors. Asdex-U and Alcator C-mod have shown reduced hydrogenic retention with tungsten clad and molybdenum plasma facing components. Once the tritium inventory approaches the administrative limit, tritium must be removed to permit continued D-T plasma operations. Several candidate techniques are being considered and need to be proven at a relevant speed and efficiency in contemporary tokamaks. Projections for ITER are discussed.

  12. Improving student retention in computer engineering technology

    NASA Astrophysics Data System (ADS)

    Pierozinski, Russell Ivan

    The purpose of this research project was to improve student retention in the Computer Engineering Technology program at the Northern Alberta Institute of Technology by reducing the number of dropouts and increasing the graduation rate. This action research project utilized a mixed methods approach of a survey and face-to-face interviews. The participants were male and female, with a large majority ranging from 18 to 21 years of age. The research found that participants recognized their skills and capability, but their capacity to remain in the program was dependent on understanding and meeting the demanding pace and rigour of the program. The participants recognized that curriculum delivery along with instructor-student interaction had an impact on student retention. To be successful in the program, students required support in four domains: academic, learning management, career, and social.

  13. Nursing workforce retention: challenging a bullying culture.

    PubMed

    Stevens, Stella

    2002-01-01

    Discussions surrounding nursing shortages typically focus on recruitment, but retention is also a problem. Emerging research suggests that intimidation in the nursing workforce is a problem that planners need to deal with as part of an overall strategy aimed at maintaining a balance between supply and demand. This paper explores issues surrounding intimidation in the nursing workforce and looks at how one major teaching hospital in Australia attempted to address the problem. PMID:12224882

  14. 300 Area Building Retention Evaluation Mitigation Plan

    SciTech Connect

    D. J. McBride

    2007-07-03

    Evaluate the long-term retention of several facilities associated with the PNNL Capability Replacement Laboratory and other Hanfor mission needs. WCH prepared a mitigation plan for three scenarios with different release dates for specific buildings. The evaluations present a proposed plan for providing utility services to retained facilities in support of a long-term (+20 year) lifespan in addition to temporary services to buildings with specified delayed release dates.

  15. Recognition, prevention and management of sputum retention.

    PubMed

    Law, Carol

    Tracheobronchial secretions are an important part of the respiratory system's defence. The excess secretions that are cleared from the airways by coughing or huffing (Pryor and Webber, 1998) are known as sputum, the production of which is always abnormal. The colour, consistency, smell and volume of sputum provides information to support both the diagnosis and management of the patient's clinical condition. Sputum retention occurs when patients are unable to clear secretions from their respiratory tract by themselves or with assistance. PMID:12838649

  16. 76 FR 24089 - Credit Risk Retention

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-29

    ...The OCC, Board, FDIC, Commission, FHFA, and HUD (the Agencies) are proposing rules to implement the credit risk retention requirements of section 15G of the Securities Exchange Act of 1934 (15 U.S.C. 78o- 11), as added by section 941 of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Section 15G generally requires the securitizer of asset-backed securities to retain not less......

  17. Effects of the Memorization of Rule Statements on Performance, Retention, and Transfer in a Computer-Based Learning Task.

    ERIC Educational Resources Information Center

    Towle, Nelson J.

    Research sought to determine whether memorization of rule statements before, during or after instruction in rule application skills would facilitate the acquisition and/or retention of rule-governed behavior as compared to no-rule statement memorization. A computer-assisted instructional (CAI) program required high school students to learn to a…

  18. Qualitative Insights into Faculty Use of Student Support Services with Online Students at Risk: Implications for Student Retention

    ERIC Educational Resources Information Center

    Russo-Gleicher, Rosalie J.

    2013-01-01

    This article provides qualitative insights into the ways that faculty can impact retention rates of online students. Semi-structured, in-depth interviews were conducted at random with 16 faculty who teach online courses at a community college in the Northeast. Faculty were asked to describe behaviors of online students that made them feel…

  19. Long-Term Retention of Flying Skills: A Review of the Literature. Final Report 76-35.

    ERIC Educational Resources Information Center

    Prophet, Wallace W.

    This is a survey of the state of behavioral science knowledge related to long-term retention of flying skills completed for the U.S. Air Force (USAF). The report contains a survey of selected agencies and knowledgeable individuals as well as a literature review. (A list of libraries, agencies, and individuals consulted is appended, but a complete…

  20. Maternal stress predicts postpartum weight retention.

    PubMed

    Whitaker, Kara; Young-Hyman, Deborah; Vernon, Marlo; Wilcox, Sara

    2014-11-01

    Postpartum weight retention (PPWR) is a significant contributor to the development of overweight and obesity in women of childbearing age. Stress may be a key mechanism making it more difficult for mothers to lose weight in the year following delivery. The aim of this study was to assess whether specific aspects of parenting stress and life stress influence postpartum weight retention in new mothers. Women in late pregnancy or up to 2 months postpartum (n = 123) were enrolled in the study and followed through the first year postpartum. Linear regression models evaluated the associations of parenting stress (isolation, attachment and depressive symptoms) as well as overall life stress at 2, 6, and 12 months postpartum with PPWR at 6 and 12 months. During the first year postpartum, higher depression and life stress were significantly associated with greater PPWR. As the effect of depression diminished, the effect of life stress became significant. Contrary to hypothesized relationships, fewer problems with attachment and less social isolation were significantly associated with greater PPWR. Higher gestational weight gain and African American race were also significantly associated with greater PPWR at both 6 and 12 months. Different types of stress predict weight retention in first time mothers during the first year postpartum. Understanding the relationships between parenting stress, concurrent life stress and PPWR can enhance the development of future interventions that specifically target self-identified stressors, leading to improved weight related outcomes. PMID:24760321

  1. Deuterium Retention in NSTX with Lithium Conditioning

    SciTech Connect

    Skinner, C. H.; Allain, J. P.; Blanchard, W.; Kugel, H. W.; Maingi, Rajesh; Roquemore, L.; Soukhanovskii, V. A.; Taylor, C. N.

    2011-01-01

    High (approximate to 90%) deuterium retention was observed in NSTX gas balance measurements both with- and without lithiumization of the carbon plasma-facing components. The gas retained in ohmic discharges was measured by comparing the vessel pressure rise after a discharge to that of a gas-only pulse with the pumping valves closed. For neutral beam heated discharges the gas input and gas pumped by the NB cryopanels were tracked. The discharges were followed by outgassing of deuterium that reduced the retention. The relationship between retention and surface chemistry was explored with a new plasma-material interface probe connected to an in vacuo surface science station that exposed four material samples to the plasma. XPS and TDS analysis demonstrated that binding of D atoms in graphite is fundamentally changed by lithium - in particular atoms are weakly bonded in regions near lithium atoms bound to either oxygen or the carbon matrix. This is in contrast to the strong ionic bonding that occurs between D and pure Li. (C) 2010 Elsevier B.V. All rights reserved.

  2. Deuterium retention in NSTX with lithium conditioning

    NASA Astrophysics Data System (ADS)

    Skinner, C. H.; Allain, J. P.; Blanchard, W.; Kugel, H. W.; Maingi, R.; Roquemore, L.; Soukhanovskii, V.; Taylor, C. N.

    2011-08-01

    High (≈90%) deuterium retention was observed in NSTX gas balance measurements both with- and without lithiumization of the carbon plasma-facing components. The gas retained in ohmic discharges was measured by comparing the vessel pressure rise after a discharge to that of a gas-only pulse with the pumping valves closed. For neutral beam heated discharges the gas input and gas pumped by the NB cryopanels were tracked. The discharges were followed by outgassing of deuterium that reduced the retention. The relationship between retention and surface chemistry was explored with a new plasma-material interface probe connected to an in vacuo surface science station that exposed four material samples to the plasma. XPS and TDS analysis demonstrated that binding of D atoms in graphite is fundamentally changed by lithium - in particular atoms are weakly bonded in regions near lithium atoms bound to either oxygen or the carbon matrix. This is in contrast to the strong ionic bonding that occurs between D and pure Li.

  3. Retention of perceptual generalization of fear extinction.

    PubMed

    Pappens, Meike; Schroijen, Mathias; Van den Bergh, Omer; Van Diest, Ilse

    2015-12-01

    Fear reduction obtained during a fear extinction procedure can generalize from the extinction stimulus to other perceptually similar stimuli. Perceptual generalization of fear extinction typically follows a perceptual gradient, with increasing levels of fear reduction the more a stimulus resembles the extinction stimulus. The current study aimed to investigate whether perceptual generalization of fear extinction can be observed also after a retention interval of 24h. Fear was acquired to three geometrical figures of different sizes (CS(+), CS1(+) and CS2(+)) by consistently pairing them with a short-lasting suffocation experience (US). Three other geometrical figures that were never followed by the US served as control stimuli (CS(-), CS1(-), CS2(-)). Next, only the CS(+) was extinguished by presenting it in the absence of the US. One day later, fear responses to all stimuli were assessed without any US-presentation. Outcome measures included startle blink EMG, skin conductance, US expectancy, respiratory rate and tidal volume. On day 2 spontaneous recovery of fear was observed in US expectancy and tidal volume, but not in the other outcomes. Evidence for the retention of fear extinction generalization was present in US expectancy and skin conductance, but a perceptual gradient in the retention of generalized fear extinction could not be observed. PMID:25623628

  4. Gastric retention properties of superporous hydrogel composites.

    PubMed

    Chen, J; Blevins, W E; Park, H; Park, K

    2000-02-14

    In many applications, usefulness of conventional hydrogels is limited by their slow swelling. To improve the swelling property of the conventional hydrogels, we have synthesized superporous hydrogels (SPHs) which swell fast to equilibrium size in minutes due to water uptake by capillary wetting through numerous interconnected open pores. The swelling ratio was also large in the range of hundreds. The mechanical strength of the highly swollen SPHs was increased by adding a composite material during the synthesis. The composite material used in the synthesis of SPH composites was Ac-Di-Sol((R)) (croscarmellose sodium). The gastric retention property of the prepared SPH composites was tested in dogs both in fasted and fed conditions. The SPH composites were placed in a hard gelatin capsule (size 000) for oral administration. All dogs tested were fasted for 36 h before experiments. Under the fasted condition, the SPH composite remained in the stomach for 2-3 h after before breaking into two pieces and being emptied. When food was given before the experiment just once following 36 h of fasting, the SPH composite remained in the stomach for more than 24 h, even though the fed condition was maintained only for the first few hours. Our study indicated that SPH composites possessed three properties necessary for gastric retention: fast swelling; superswelling; and high mechanical strength. While more improvements need to be made, the SPH composites provide the basis for the development of effective long-term gastric retention devices. PMID:10640644

  5. DRAM Weak Cell Characterization for Retention Time.

    PubMed

    Kang, Jonghyuk; Lee, Sungho; Choi, Byoungdeog

    2016-05-01

    This work proposes a sequence of tests for detecting refresh weak cells based on data retention time distribution in the main cell array of DRAMs and verify the feasibility of the proposed method through analysis of 30 nm design-rule DRAM cells with Recess Channel Array Transistor (RCAT) and Buried Channel Array Transistor (BCAT). Basic idea of the proposed mechanism is to test with different bias conditions and break down retention failures based on their root causes such as Gate Induced Drain Leakage, sub-threshold leakage and junction leakage. This categorization helps to determine the physical locations of each failure group, enabling precise Physical Failure Analysis (PFA). The characterization of data retention weak cells for 30 nm design rule DRAMs with BCAT and RCAT has been investigated. Most weak cells were classified as GIDL leaky cells in both cases. In the case of BCAT, the distance between the word line and the storage node, caused by the process distribution, is the main origin of weak cells. In the case of RCAT, the sharp corner of the active layer in the storage node is the main cause of weak cells. PMID:27483878

  6. Measuring the value of customer retention

    SciTech Connect

    Monts, K.; Bonevac, B.; Lauer, J.; Tessema, D.

    1997-05-01

    Competition will require changes in how market research is conducted and how customers are pursued. The question remains: How does one approach customer retention in a way that provides meaningful guidelines? The conventional wisdom is that {open_quotes}the business of business is selling.{close_quotes} There is some truth to this, but the key question today is: What bearing does this have on how to run a business in a competitive environment? A recent article in the Harvard Business Review noted that, {open_quotes}Increasingly, companies are less focused on selling products and more interested in keeping customers.{close_quotes} Indeed, some observers have posited a natural societal evolutionary trend toward a shift of emphasis toward customer retention vis-a-vis customer acquisition, as a consequence of the primary marketing communication technology shifting from {open_quotes}broadcast{close_quotes} (where messages are sent out to inchoate masses) to {open_quotes}interactive{close_quotes} (where relationships are cultivated with precisely defined market niches or individual customers). The business of growing a business, then, can be framed as a matter of getting customers and keeping them so as to grow the value of the customer base to its fullest potential. In these terms, setting a marketing budget becomes the task of balancing what is spent on customer acquisition with what is spent on retention.

  7. Maternal Stress Predicts Postpartum Weight Retention

    PubMed Central

    Whitaker, Kara; Vernon, Marlo; Wilcox, Sara

    2014-01-01

    Postpartum weight retention (PPWR) is a significant contributor to the development of overweight and obesity in women of childbearing age. Stress may be a key mechanism making it more difficult for mothers to lose weight in the year following delivery. The aim of this study was to assess whether specific aspects of parenting stress and life stress influence postpartum weight retention in new mothers. Women in late pregnancy or up to 2 months postpartum (n = 123) were enrolled in the study and followed through the first year postpartum. Linear regression models evaluated the associations of parenting stress (isolation, attachment and depressive symptoms) as well as overall life stress at 2, 6, and 12 months postpartum with PPWR at 6 and 12 months. During the first year postpartum, higher depression and life stress were significantly associated with greater PPWR. As the effect of depression diminished, the effect of life stress became significant. Contrary to hypothesized relationships, fewer problems with attachment and less social isolation were significantly associated with greater PPWR. Higher gestational weight gain and African American race were also significantly associated with greater PPWR at both 6 and 12 months. Different types of stress predict weight retention in first time mothers during the first year postpartum. Understanding the relationships between parenting stress, concurrent life stress and PPWR can enhance the development of future interventions that specifically target self-identified stressors, leading to improved weight related outcomes. PMID:24760321

  8. High Efficiency Diffusion Molecular Retention Tumor Targeting

    PubMed Central

    Guo, Yanyan; Yuan, Hushan; Cho, Hoonsung; Kuruppu, Darshini; Jokivarsi, Kimmo; Agarwal, Aayush; Shah, Khalid; Josephson, Lee

    2013-01-01

    Here we introduce diffusion molecular retention (DMR) tumor targeting, a technique that employs PEG-fluorochrome shielded probes that, after a peritumoral (PT) injection, undergo slow vascular uptake and extensive interstitial diffusion, with tumor retention only through integrin molecular recognition. To demonstrate DMR, RGD (integrin binding) and RAD (control) probes were synthesized bearing DOTA (for 111 In3+), a NIR fluorochrome, and 5 kDa PEG that endows probes with a protein-like volume of 25 kDa and decreases non-specific interactions. With a GFP-BT-20 breast carcinoma model, tumor targeting by the DMR or IV methods was assessed by surface fluorescence, biodistribution of [111In] RGD and [111In] RAD probes, and whole animal SPECT. After a PT injection, both probes rapidly diffused through the normal and tumor interstitium, with retention of the RGD probe due to integrin interactions. With PT injection and the [111In] RGD probe, SPECT indicated a highly tumor specific uptake at 24 h post injection, with 352%ID/g tumor obtained by DMR (vs 4.14%ID/g by IV). The high efficiency molecular targeting of DMR employed low probe doses (e.g. 25 ng as RGD peptide), which minimizes toxicity risks and facilitates clinical translation. DMR applications include the delivery of fluorochromes for intraoperative tumor margin delineation, the delivery of radioisotopes (e.g. toxic, short range alpha emitters) for radiotherapy, or the delivery of photosensitizers to tumors accessible to light. PMID:23505478

  9. Improved motor sequence retention by motionless listening.

    PubMed

    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. PMID:22434336

  10. From vigilance to violence: mate retention tactics in married couples.

    PubMed

    Buss, D M; Shackelford, T K

    1997-02-01

    Although much research has explored the adaptive problems of mate selection and mate attraction, little research has investigated the adaptive problem of mate retention. We tested several evolutionary psychological hypotheses about the determinants of mate retention in 214 married people. We assessed the usage of 19 mate retention tactics ranging from vigilance to violence. Key hypothesized findings include the following: Men's, but not women's, mate retention positively covaried with partner's youth and physical attractiveness. Women's, but not men's, mate retention positively covaried with partner's income and status striving. Men's mate retention positively covaried with perceived probability of partner's infidelity. Men, more than women, reported using resource display, submission and debasement, and intrasexual threats to retain their mates. Women, more than men, reported using appearance enhancement and verbal signals of possession. Discussion includes an evolutionary psychological analysis of mate retention in married couples. PMID:9107005

  11. Annuaire du Bureau des longitudes - 2006

    NASA Astrophysics Data System (ADS)

    Imcce; Bureau Des Longitudes

    2005-07-01

    This annual publication provides ephemerides and data to the use of professionnal and amateur astronomers. Divided in 11 chapters it covers concordance of various calendars, explanation of fondamental astronomy and various time scales, explanation for the use of ephemerides; tables provide ephemerides (positions, rise/set/passage) of the Sun and the Moon, planets, planetary satellites, asteroids, comets, bright stars; data and explanation for the physical observation of the surface of the Sun, the Moon, and planets; chart of the sky and a list of constellations and galaxies; prediction and ephemerides for astronomical phenomenon: occultation by the moon, stellar occultations by asteroids and appulses, solar eclipses and lunar eclipses; and an additional review about a hot scientific topic, this year: "Legendre et le méridien terrestre, 200 ans après". Cette publication annuelle fournit des éphémérides et des données à l'usage des astronomes professionnels et des astronomes amateurs. Composée de 11 chapitres elle comprend les rubriques sur les différents calendriers et leurs concordance, les fêtes légales en France, les dates et décrets sur les heures légales en France métropolitaine ; une introduction à l'astronomie fondamentale et aux différentes échelles de temps, des explications sur l'utilisation des éphémérides ; des tables fournissent les éphémérides (positions, heures de lever/coucher/passage) du Soleil et de la Lune, de planètes, de satellites naturels, d'astéroïdes, de comètes, d'étoiles brillantes ; des données pour l'observation de la surface du Soleil, de la Lune, et des planètes ; des cartes du ciel ainsi qu'une liste de constellations et de galaxies ; des prédictions des phénomènes astronomiques : occultation par la Lune, occultation stellaires par des astéroïdes et appulses, éclipses de Soleil et de la Lune; la liste et les coordonnées des observatoires astronomiques les plus connus ; et enfin un cahier th

  12. A locomotor adaptation including explicit knowledge and removal of postadaptation errors induces complete 24-hour retention.

    PubMed

    Hussain, Sara J; Hanson, Angela S; Tseng, Shih-Chiao; Morton, Susanne M

    2013-08-01

    Locomotor patterns are generally very consistent but also contain a high degree of adaptability. Motor adaptation is a short-term type of learning that utilizes this plasticity to alter locomotor behaviors quickly and transiently. In this study, we used a variation of an adaptation paradigm in order to test whether explicit information as well as the removal of the visual error signal after adaptation could improve retention of a newly learned walking pattern 24 h later. On two consecutive days of testing, participants walked on a treadmill while viewing a visual display that showed erroneous feedback of swing times for each leg. Participants were instructed to use this feedback to monitor and adjust swing times so they appeared symmetric within the display. This was achieved by producing a novel interlimb asymmetry between legs. For both legs, we measured adaptation magnitudes and rates and immediate and 24-h retention magnitudes. Participants showed similar adaptation on both days but a faster rate of readaptation on day 2. There was complete retention of adapted swing times on the increasing leg (i.e., no evidence of performance decay over 24 h). Overall, these findings suggest that the inclusion of explicit information and the removal of the visual error signal are effective in inducing full retention of adapted increases in swing time over a moderate (24 h) interval of time. PMID:23741038

  13. Grafting zwitterionic polymer onto cryogel surface enhances protein retention in steric exclusion chromatography on cryogel monolith.

    PubMed

    Tao, Shi-Peng; Zheng, Jie; Sun, Yan

    2015-04-10

    Cryogel monoliths with interconnected macropores (10-100μm) and hydrophilic surfaces can be employed as chromatography media for protein retention in steric exclusion chromatography (SXC). SXC is based on the principle that the exclusion of polyethylene glycol (PEG) on both a hydrophilic chromatography surface and a protein favors their association, leading to the protein retention on the chromatography surface. Elution of the retained protein can be achieved by reducing PEG concentration. In this work, the surface of polyacrylamide-based cryogel monolith was modified by grafting zwitterionic poly(carboxybetaine methacrylate) (pCBMA), leading the increase in the surface hydrophilicity. Observation by scanning electron microscopy revealed the presence of the grafted pCBMA chain clusters on the cryogel surface, but pCBMA grafting did not result in the changes of the physical properties of the monolith column, and the columns maintained good recyclability in SXC. The effect of the surface grafting on the SXC behavior of γ-globulin was investigated in a wide flow rate range (0.6-12cm/min). It was found that the dynamic retention capacity increased 1.4-1.8 times by the zwitterionic polymer grafting in the flow rate range of 1.5-12cm/min. The mechanism of enhanced protein retention on the zwitterionic polymer-grafted surface was proposed. The research proved that zwitterionic polymer modification was promising for the development of new materials for SXC applications. PMID:25757821

  14. Transport of Sulfide-Reduced Graphene Oxide in Saturated Quartz Sand: Cation-Dependent Retention Mechanisms.

    PubMed

    Xia, Tianjiao; Fortner, John D; Zhu, Dongqiang; Qi, Zhichong; Chen, Wei

    2015-10-01

    We describe how the reduction of graphene oxide (GO) via environmentally relevant pathways affects its transport behavior in porous media. A pair of sulfide-reduced GOs (RGOs), prepared by reducing 10 mg/L GO with 0.1 mM Na2S for 3 and 5 days, respectively, exhibited lower mobility than did parent GO in saturated quartz sand. Interestingly, decreased mobility cannot simply be attributed to the increased hydrophobicity and aggregation upon GO reduction because the retention mechanisms of RGOs were highly cation-dependent. In the presence of Na(+) (a representative monovalent cation), the main retention mechanism was deposition in the secondary energy minimum. However, in the presence of Ca(2+) (a model divalent cation), cation bridging between RGO and sand grains became the most predominant retention mechanism; this was because sulfide reduction markedly increased the amount of hydroxyl groups (a strong metal-complexing moiety) on GO. When Na(+) was the background cation, increasing pH (which increased the accumulation of large hydrated Na(+) ions on grain surface) and the presence of Suwannee River humic acid (SRHA) significantly enhanced the transport of RGO, mainly due to steric hindrance. However, pH and SRHA had little effect when Ca(2+) was the background cation because neither affected the extent of cation bridging that controlled particle retention. These findings highlight the significance of abiotic transformations on the fate and transport of GO in aqueous systems. PMID:26348539

  15. Chemometric study of retention on binary stationary phases in gas chromatography.

    PubMed

    Bouzouane, S; Righezza, M; Touabet, A

    2012-02-01

    Using gas chromatography, data analysis is performed on a dataset consisting of 486 retention indices, 27 standards (ramified alkanes, aliphatic alcohols, and aromatic compounds), 6 pure and binary stationary phases, and three temperatures. The behavior of the pure stationary phases (OV-3, OV-225, OV-61-OH, and OV-1701-OH) and the binary stationary phases (OV-3/OV-225 and OV-61-OH/OV-1701-OH) at different temperatures (60°C-100°C) is investigated with factor and topological analysis. The influence of temperature and the nature of the mixed stationary phases on the retention indices is studied by correspondence factor analysis (CFA). The non-additivity of the retention properties of the pure phases used as mixed phases is clearly established by CFA. The topological analysis of the substituent's effect is investigated with a DARC/PELCO procedure and shows the particular influence of the stationary phase composition on the retention. The substituent effect is measured for the pure and binary stationary phases at various temperatures. The evolution of the substituent effect from the pure stationary phases to the binary phases is discussed. PMID:22298764

  16. Nickel migration and retention dynamics in natural soil columns

    NASA Astrophysics Data System (ADS)

    Raveh-Rubin, Shira; Edery, Yaniv; Dror, Ishai; Berkowitz, Brian

    2015-09-01

    Nickel migration measured in laboratory-scale, natural soil column experiments is shown to display anomalous (non-Fickian) transport, nonequilibrium adsorption and desorption patterns, and precipitation/dissolution. Similar experiments using a conservative tracer also exhibit anomalous behavior. The occurrence of ion exchange of nickel, mainly with calcium (but also with other soil components), is measured in both batch and flow-through column experiments; adsorption and desorption isotherms demonstrate hysteresis. Strong retention of nickel during transport in soil columns leads to delayed initial breakthrough (˜40 pore volumes), slow increase in concentration, and extended concentration tailing at long times. We describe the mechanisms of transport and retention in terms of a continuous time random walk (CTRW) model, and use a particle tracking formulation to simulate nickel migration in the column. This approach allows us to capture the non-Fickian transport and the subtle local effects of adsorption/desorption and precipitation/dissolution. Consideration also of preferential pathways accounts for the evolution of the measured breakthrough curve and measured spatial concentration profiles. The model uses non-Fickian transport parameters estimated from the conservative tracer and, as a starting point, adsorption/desorption parameters based on batch experiments and a precipitation parameter based on Ksp values. The batch parameters are found to underestimate the actual amount of adsorption. We suggest that the sorption and precipitation/dissolution dynamics, and resulting breakthrough curves, are influenced strongly by preferential pathways; such pathways significantly alter the availability of sorption sites and ion availability for precipitation. Analysis of these results provides further understanding of the interaction and dynamics among transport, precipitation, and sorption mechanisms in natural soil.

  17. Recruitment and Retention of Mental Health Workers in Ghana

    PubMed Central

    Jack, Helen; Canavan, Maureen; Ofori-Atta, Angela; Taylor, Lauren; Bradley, Elizabeth

    2013-01-01

    Introduction The lack of trained mental health workers is a primary contributor to the mental health treatment gap worldwide. Despite the great need to recruit and retain mental health workers in low-income countries, little is known about how these workers perceive their jobs and what drives them to work in mental health care. Using qualitative interviews, we aimed to explore factors motivating mental health workers in order to inform interventions to increase recruitment and retention. Methods We conducted 28 in-depth, open-ended interviews with staff in Ghana’s three public psychiatric hospitals. We used the snowballing method to recruit participants and the constant comparative method for qualitative data analysis, with multiple members of the research team participating in data coding to enhance the validity and reliability of the analysis. The use of qualitative methods allowed us to understand the range and depth of motivating and demotivating factors. Results Respondents described many factors that influenced their choice to enter and remain in mental health care. Motivating factors included 1) desire to help patients who are vulnerable and in need, 2) positive day-to-day interactions with patients, 3) intellectual or academic interest in psychiatry or behavior, and 4) good relationships with colleagues. Demotivating factors included 1) lack of resources at the hospital, 2) a rigid supervisory hierarchy, 3) lack of positive or negative feedback on work performance, and 4) few opportunities for career advancement within mental health. Conclusions Because many of the factors are related to relationships, these findings suggest that strengthening the interpersonal and team dynamics may be a critical and relatively low cost way to increase worker motivation. The data also allowed us to highlight key areas for resource allocation to improve both recruitment and retention, including risk pay, adequate tools for patient care, improved hospital work environment

  18. Quantitative structure retention relationship studies for predicting relative retention times of chlorinated phenols on gas chromatography.

    PubMed

    Li, Shi-Yin; Sun, Cheng; Wang, Yu; Xu, Shi-Fen; Yao, Shu-Chun; Wang, Lian-Sheng

    2002-07-01

    A new method of quantitative structure-retention relationship (QSRR) studies was reported for predicting gas chromatography (GC) relative retention times (RRTs) of chlorinated phenols (CPs) using a DB-5 column. Chemical descriptors were calculated from the molecular structure of CPs and related to their gas chromatographic RRTs by using multiple linear regression analysis. The proposed model had a multiple square correlation coefficient R2 = 0.970, standard error SE = 0.0472, and significant level P = 0.0000. The QSRR model also reveals that the gas chromatographic relative retention times of CPs are associated with physicochemical property interactions with the stationary phase, and influenced by the number of chlorine and oxygen in the CP mOlecules. PMID:12211996

  19. Transport quantique dans des nanostructures

    NASA Astrophysics Data System (ADS)

    Naud, C.

    2002-09-01

    structure des oscillations de conductance en fonction du flux du champ magnétique de période h/e dont l'amplitude est beaucoup plus importante que celle mesurée sur un réseau carré de même dimension. Cette différence constitue une signature d'un effet de localisation induit par le champ magnétique sur la topologie mathcal{T}3. Pour des valeurs spécifiques du champ magnétique, du fait des interférences destructives Aharonov-Bohm, la propagation des fonctions d'ondes est limitée à un ensemble fini de cellule du réseau appelé cage. De la dépendance en température des oscillations de période h/e mesurées sur le réseau mathcal{T}3 nous avons tiré une longueur caractéristique qui peut être rattachée au périmètre des cages. Un phénomène inattendu fut l'observation, pour des champs magnétiques plus importants, d'un doublement de fréquence des oscillations. Ces oscillations de période h/2e pouvant avoir une amplitude supérieure aux oscillations de période h/e, une interprétation en terme d'harmonique n'est pas possible. Enfin, l'influence de la largeur électrique des fils constituant le réseau et donc celle du nombre de canaux par brin a été étudiée en réalisant des grilles électrostatique. Les variations de l'amplitude des signaux en h/e et h/2e en fonction de la tension de grille ont été mesurés.

  20. Sexual Behaviors in Autism: Problems of Definition and Management.

    ERIC Educational Resources Information Center

    Realmuto, George M.; Ruble, Lisa A.

    1999-01-01

    Explores the problems of definition of sexual behaviors in individuals with autism and describes a case that highlights the difficulties of management. After failure of behavioral and educational programs, a testosterone-suppressing medication was used resulting in suppression of public masturbation behaviors and retention of the participant's…

  1. Gas bubble retention and its effect on waste properties: Retention mechanisms, viscosity, and tensile and shear strengths

    SciTech Connect

    Gauglitz, P.A.; Rassat, S.D.; Powell, M.R.

    1995-08-01

    Several of the underground nuclear storage tanks at Hanford have been placed on a flammable gas watch list, because the waste is either known or suspected to generate, store, and episodically release flammable gases. Because retention and episodic release of flammable gases from these tanks containing radioactive waste slurries are critical safety concerns, Pacific Northwest Laboratory (PNL) is studying physical mechanisms and waste properties that contribute to the episodic gas release from these storage tanks. This study is being conducted for Westinghouse Hanford Company as part of the PNL Flammable Gas project. Previous investigations have concluded that gas bubbles are retained by the slurry or sludge that has settled at the bottom of the tanks; however, the mechanisms responsible for the retention of these bubbles are not well understood. Understanding the rheological behavior of the waste, particularly of the settled sludge, is critical to characterizing the tendency of the waste to retain gas bubbles and the dynamics of how these bubbles are released from the waste. The presence of gas bubbles is expected to affect the rheology of the sludge, specifically its viscosity and tensile and shear strengths, but essentially no literature data are available to assess the effect of bubbles. The objectives of this study were to conduct experiments and develop theories to understand better how bubbles are retained by slurries and sludges, to measure the effect of gas bubbles on the viscosity of simulated slurries, and to measure the effect of gas bubbles on the tensile and shear strengths of simulated slurries and sludges. In addition to accomplishing these objectives, this study developed correlations, based on the new experimental data, that can be used in large-scale computations of waste tank physical phenomena.

  2. LARES Mission: Separation and Retention Subsystem

    NASA Technical Reports Server (NTRS)

    Bursi, Alessandro; Camilli, Pierluigi; Piredda, Claudio; Babini, Gianni; Mangraviti, Elio

    2014-01-01

    As part of the Lares (LAser RElativity Satellite) mission, an all-Italian scientific mission launched with the Vega maiden flight in February 2012, a mechanical separation and retention subsystem (SSEP) has been developed to retain the LARES satellite during launch and release it in the final orbit. The design flow was based on the identification of the driving requirements and critical areas to guide the trade-off, design, analysis and test activities. In particular, the SSEP had to face very high environmental loads and to minimize the contact areas with the satellite that had a spherical shape. The test activity overview is provided.

  3. Survey on workforce retention and attrition

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2013-03-01

    The Society of Petroleum Engineers (SPE) is conducting a survey to gather information on why technical professionals change jobs or quit working. The survey, prompted by concern about the retention of skilled workers, aims to provide information to employers that can assist them in addressing practices that can lead to significant workforce attrition. To participate in the survey, which is open to everyone (including those who are not SPE members), go to http://research.spe.org/se.ashx?s=705E3F1335720258 through 15 May 2013. For more information, contact speresearch@spe.org.

  4. Workforce Challenges and Retention Success Stories

    NASA Technical Reports Server (NTRS)

    Donohue, John T.

    2008-01-01

    This viewgraph document discusses the current and future challenges in building and retaining the required workforce of scientist and engineers for NASA. Specifically, the talk reviews the current situation at the Goddard Space Flight Center in Greenbelt, Maryland. Several programs at NASA for high school and college students to assist in inspiring the next generation of scientist and engineers are reviewed. The issue of retention of the best of the young scientists and engineers is also reviewed, with a brief review of several young engineers and their success with and for NASA.

  5. Dysfunctional Elimination Behaviors and Associated Complications in School-Age Children

    ERIC Educational Resources Information Center

    Kistner, Mary

    2009-01-01

    Lack of privacy, risk of bullying, limited access, lack of essential products for good hygiene, and dirty bathrooms can all contribute to encouraging a child to withhold urine and stool while in school. Withholding behaviors over time can create a condition known as dysfunctional elimination syndrome (DES). DES is any pattern of voiding or…

  6. Analysis of residual products in triethylbenzylammonium chloride by HPLC. Study of the retention mechanism.

    PubMed

    Prieto-Blanco, M C; López-Mahía, P; Prada-Rodríguez, D

    2006-04-01

    The control of industrial products for minimization of their impact on the environment and human health requires the development of specific analysis methods. Information provided by these methods about toxic components, by-products, and other derivatives may also be useful to reduce the possible impact of industrial products. The studied compound in this paper, triethylbenzylammonium chloride (TEBA), is mainly used in industrial synthesis. This quaternary compound and its residual products coming from quaternization reaction (benzyl chloride, benzaldehyde, and benzyl alcohol) are analyzed by HPLC. The separation is based on control of the silanophilic contribution to TEBA retention because of the quaternary nature of this compound. The effect of the three buffers (sodium acetate, ammonium acetate, and sodium formate) and their concentrations in the chromatographic behavior of the quaternary compound is examined. The buffer cation and anion regulate TEBA retention. Also, the concentration of the quaternary compound is another parameter that had influence in some aspects of its chromatographic behavior (e.g., retention and symmetry). The proposed method is applied to TEBA synthesis along, with the formation and removal of impurities with the results compared with those obtained for the quaternary compound benzalkonium chloride. PMID:16620516

  7. Small animal behavioral triage: a guide for practitioners.

    PubMed

    Martin, Kenneth M; Martin, Debbie; Shaw, Julie K

    2014-05-01

    Behavioral concerns are the principal cause of a weakened human-animal bond and pet relinquishment. Triaging behavioral concerns and providing early intervention may be the difference between a patient remaining in its current home or relinquishment. Prevention and intervention behavior services using a team approach may also improve pet retention through client education and appropriate assistance. Identifying and integrating qualified animal behavior professionals to assist with the hospital's behavior team ensures appropriate support is provided to the client and patient. PMID:24766692

  8. Differential Effect of Alcoholism and HIV Infection on Visuomotor Procedural Learning and Retention

    PubMed Central

    Fama, Rosemary; Rosenbloom, Margaret J.; Sassoon, Stephanie A.; Pfefferbaum, Adolf; Sullivan, Edith V.

    2012-01-01

    supports the hypothesis that alcoholism and HIV infection exert differential effects on components of visuomotor procedural learning. Further, the results provide behavioral evidence for dissociable influences of frontocerebellar and frontostriatal disruption to visuomotor procedural learning and retention. PMID:22823125

  9. Reframing Retention: New Evidence from within the Elementary School Classroom on Post-Retention Performance

    ERIC Educational Resources Information Center

    Gottfried, Michael A.

    2012-01-01

    This study contributes a novel perspective on grade retention by empirically examining how classroom composition relates to the standardized-testing performance of grade-retained students in their post-retained years. This evaluation employed a sample of entire cohorts of urban elementary school children in the Philadelphia School District over 6…

  10. Retention: Tactic for the Eighties [and] Retention Improvement: Selected Case Studies. Policy Briefs.

    ERIC Educational Resources Information Center

    Jackley, Janet P.; Henderson, Cathy

    The need to examine college student attrition as an approach to the expected demographic decline in the 1980s, and case studies that demonstrate retention improvement and successful techniques are considered. Information is presented on the progress of typical freshmen (graduates, transfers, and dropouts) and patterns of interrupting studies.…

  11. Football and Freshmen Retention: Examining the Impact of College Football on Institutional Retention Rates

    ERIC Educational Resources Information Center

    Jones, Willis A.

    2010-01-01

    Student retention has been one of the more researched topics in the study of American higher education over the past 20 years (Braxton, Hirschy, & McClendon, 2004; Pascarella & Terenzini, 2005). Very little of this research, however, has attempted to examine the impact of college athletics on an institution's ability to retain students. This…

  12. Education for Sustainable Development and retention: unravelling a research agenda

    NASA Astrophysics Data System (ADS)

    Lotz-Sisitka, Heila

    2010-06-01

    This paper considers the question of what education for sustainable development (ESD) research might signify when linked to the concept of "retention", and how this relation (ESD and retention) might be researched. It considers two different perspectives on retention, as revealed through educational research trajectories, drawing on existing research and case studies. Firstly, it discusses an ESD research agenda that documents retention by focusing on the issue of keeping children in schools. This research agenda is typical of the existing discourses surrounding Education for All (EFA). It then discusses a related ESD research agenda that focuses more on the pedagogical and curricular aspects of retention, as this provides for a deeper understanding of how ESD can contribute to improving the quality of teaching and learning within a wider EFA retention agenda.

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

    PubMed

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

    2016-07-01

    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. PMID:27160325

  14. Radionuclide Retention in Concrete Wasteforms - FY13

    SciTech Connect

    Snyder, Michelle MV; Golovich, Elizabeth C.; Wellman, Dawn M.; Crum, Jarrod V.; Lapierre, Robert; Dage, Denomy C.; Parker, Kent E.; Cordova, Elsa A.

    2013-10-15

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of low-level waste and mixed low-level waste, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

  15. Hydrogen retention in ion irradiated steels

    SciTech Connect

    Hunn, J.D.; Lewis, M.B.; Lee, E.H.

    1998-11-01

    In the future 1--5 MW Spallation Neutron Source, target radiation damage will be accompanied by high levels of hydrogen and helium transmutation products. The authors have recently carried out investigations using simultaneous Fe/He,H multiple-ion implantations into 316 LN stainless steel between 50 and 350 C to simulate the type of radiation damage expected in spallation neutron sources. Hydrogen and helium were injected at appropriate energy and rate, while displacement damage was introduced by nuclear stopping of 3.5 MeV Fe{sup +}, 1 {micro}m below the surface. Nanoindentation measurements showed a cumulative increase in hardness as a result of hydrogen and helium injection over and above the hardness increase due to the displacement damage alone. TEM investigation indicated the presence of small bubbles of the injected gases in the irradiated area. In the current experiment, the retention of hydrogen in irradiated steel was studied in order to better understand its contribution to the observed hardening. To achieve this, the deuterium isotope ({sup 2}H) was injected in place of natural hydrogen ({sup 1}H) during the implantation. Trapped deuterium was then profiled, at room temperature, using the high cross-section nuclear resonance reaction with {sup 3}He. Results showed a surprisingly high concentration of deuterium to be retained in the irradiated steel at low temperature, especially in the presence of helium. There is indication that hydrogen retention at spallation neutron source relevant target temperatures may reach as high as 10%.

  16. High retention membrane bioreactors: challenges and opportunities.

    PubMed

    Luo, Wenhai; Hai, Faisal I; Price, William E; Guo, Wenshan; Ngo, Hao H; Yamamoto, Kazuo; Nghiem, Long D

    2014-09-01

    Extensive research has focussed on the development of novel high retention membrane bioreactor (HR-MBR) systems for wastewater reclamation in recent years. HR-MBR integrates high rejection membrane separation with conventional biological treatment in a single step. High rejection membrane separation processes currently used in HR-MBR applications include nanofiltration, forward osmosis, and membrane distillation. In these HR-MBR systems, organic contaminants can be effectively retained, prolonging their retention time in the bioreactor and thus enhancing their biodegradation. Therefore, HR-MBR can offer a reliable and elegant solution to produce high quality effluent. However, there are several technological challenges associated with the development of HR-MBR, including salinity build-up, low permeate flux, and membrane degradation. This paper provides a critical review on these challenges and potential opportunities of HR-MBR for wastewater treatment and water reclamation, and aims to guide and inform future research on HR-MBR for fast commercialisation of this innovative technology. PMID:24996563

  17. Global phosphorus retention by river damming.

    PubMed

    Maavara, Taylor; Parsons, Christopher T; Ridenour, Christine; Stojanovic, Severin; Dürr, Hans H; Powley, Helen R; Van Cappellen, Philippe

    2015-12-22

    More than 70,000 large dams have been built worldwide. With growing water stress and demand for energy, this number will continue to increase in the foreseeable future. Damming greatly modifies the ecological functioning of river systems. In particular, dam reservoirs sequester nutrient elements and, hence, reduce downstream transfer of nutrients to floodplains, lakes, wetlands, and coastal marine environments. Here, we quantify the global impact of dams on the riverine fluxes and speciation of the limiting nutrient phosphorus (P), using a mechanistic modeling approach that accounts for the in-reservoir biogeochemical transformations of P. According to the model calculations, the mass of total P (TP) trapped in reservoirs nearly doubled between 1970 and 2000, reaching 42 Gmol y(-1), or 12% of the global river TP load in 2000. Because of the current surge in dam building, we project that by 2030, about 17% of the global river TP load will be sequestered in reservoir sediments. The largest projected increases in TP and reactive P (RP) retention by damming will take place in Asia and South America, especially in the Yangtze, Mekong, and Amazon drainage basins. Despite the large P retention capacity of reservoirs, the export of RP from watersheds will continue to grow unless additional measures are taken to curb anthropogenic P emissions. PMID:26644553

  18. Cooking utensil with improved heat retention

    DOEpatents

    Potter, Thomas F.; Benson, David K.; Burch, Steven D.

    1997-01-01

    A cooking utensil with improved heat retention includes an inner pot received within an outer pot and separated in a closely spaced-apart relationship to form a volume or chamber therebetween. The chamber is evacuated and sealed with foil leaves at the upper edges of the inner and outer pot. The vacuum created between the inner and outer pot, along with the minimum of thermal contact between the inner and outer pot, and the reduced radiative heat transfer due to low emissivity coatings on the inner and outer pot, provide for a highly insulated cooking utensil. Any combination of a plurality of mechanisms for selectively disabling and re-enabling the insulating properties of the pot are provided within the chamber. These mechanisms may include: a hydrogen gas producing and reabsorbing device such as a metal hydride, a plurality of metal contacts which can be adjusted to bridge the gap between the inner and outer pot, and a plurality of bimetallic switches which can selectively bridge the gap between the inner and outer pot. In addition, phase change materials with superior heat retention characteristics may be provided within the cooking utensil. Further, automatic and programmable control of the cooking utensil can be provided through a microprocessor and associated hardware for controlling the vacuum disable/enable mechanisms to automatically cook and save food.

  19. Cooking utensil with improved heat retention

    DOEpatents

    Potter, T.F.; Benson, D.K.; Burch, S.D.

    1997-07-01

    A cooking utensil with improved heat retention includes an inner pot received within an outer pot and separated in a closely spaced-apart relationship to form a volume or chamber there between. The chamber is evacuated and sealed with foil leaves at the upper edges of the inner and outer pot. The vacuum created between the inner and outer pot, along with the minimum of thermal contact between the inner and outer pot, and the reduced radiative heat transfer due to low emissivity coatings on the inner and outer pot, provide for a highly insulated cooking utensil. Any combination of a plurality of mechanisms for selectively disabling and re-enabling the insulating properties of the pot are provided within the chamber. These mechanisms may include: a hydrogen gas producing and reabsorbing device such as a metal hydride, a plurality of metal contacts which can be adjusted to bridge the gap between the inner and outer pot, and a plurality of bimetallic switches which can selectively bridge the gap between the inner and outer pot. In addition, phase change materials with superior heat retention characteristics may be provided within the cooking utensil. Further, automatic and programmable control of the cooking utensil can be provided through a microprocessor and associated hardware for controlling the vacuum disable/enable mechanisms to automatically cook and save food. 26 figs.

  20. Retention of Halogens in Waste Glass

    SciTech Connect

    Hrma, Pavel R.

    2010-05-01

    In spite of their potential roles as melting rate accelerators and foam breakers, halogens are generally viewed as troublesome components for glass processing. Of five halogens, F, Cl, Br, I, and At, all but At may occur in nuclear waste. A nuclear waste feed may contain up to 10 g of F, 4 g of Cl, and ≤100 mg of Br and I per kg of glass. The main concern is halogen volatility, producing hazardous fumes and particulates, and the radioactive iodine 129 isotope of 1.7x10^7-year half life. Because F and Cl are soluble in oxide glasses and tend to precipitate on cooling, they can be retained in the waste glass in the form of dissolved constituents or as dispersed crystalline inclusions. This report compiles known halogen-retention data in both high-level waste (HLW) and low-activity waste (LAW) glasses. Because of its radioactivity, the main focus is on I. Available data on F and Cl were compiled for comparison. Though Br is present in nuclear wastes, it is usually ignored; no data on Br retention were found.

  1. Global phosphorus retention by river damming

    PubMed Central

    Maavara, Taylor; Parsons, Christopher T.; Ridenour, Christine; Stojanovic, Severin; Dürr, Hans H.; Powley, Helen R.; Van Cappellen, Philippe

    2015-01-01

    More than 70,000 large dams have been built worldwide. With growing water stress and demand for energy, this number will continue to increase in the foreseeable future. Damming greatly modifies the ecological functioning of river systems. In particular, dam reservoirs sequester nutrient elements and, hence, reduce downstream transfer of nutrients to floodplains, lakes, wetlands, and coastal marine environments. Here, we quantify the global impact of dams on the riverine fluxes and speciation of the limiting nutrient phosphorus (P), using a mechanistic modeling approach that accounts for the in-reservoir biogeochemical transformations of P. According to the model calculations, the mass of total P (TP) trapped in reservoirs nearly doubled between 1970 and 2000, reaching 42 Gmol y−1, or 12% of the global river TP load in 2000. Because of the current surge in dam building, we project that by 2030, about 17% of the global river TP load will be sequestered in reservoir sediments. The largest projected increases in TP and reactive P (RP) retention by damming will take place in Asia and South America, especially in the Yangtze, Mekong, and Amazon drainage basins. Despite the large P retention capacity of reservoirs, the export of RP from watersheds will continue to grow unless additional measures are taken to curb anthropogenic P emissions. PMID:26644553

  2. Radionuclide Retention in Concrete Waste Forms

    SciTech Connect

    Mattigod, Shas V.; Bovaird, Chase C.; Wellman, Dawn M.; Wood, Marcus I.

    2010-09-30

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how waste form performance is affected by the full range of environmental conditions within the disposal facility; the process of waste form aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of waste form aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the waste forms come in contact with groundwater. The information presented in the report provides data that 1) quantify radionuclide retention within concrete waste form materials similar to those used to encapsulate waste in the Low-Level Waste Burial Grounds (LLBG); 2) measure the effect of concrete waste form properties likely to influence radionuclide migration; and 3) quantify the stability of uranium-bearing solid phases of limited solubility in concrete.

  3. Job embeddedness as a nurse retention strategy for rural hospitals.

    PubMed

    Stroth, Chandra

    2010-01-01

    RN turnover is expensive and disruptive for rural hospitals, constraining finances, impacting patient care, and stressing remaining nurses. Recent investigations have described a promising new construct related to employee retention: job embeddedness. Leaders in nonhealthcare organizations have adopted a job-embeddedness model to guide retention strategies and experienced a subsequent reduction in turnover. The author explores job embeddedness as an effective retention plan strategy for rural hospitals. PMID:20010375

  4. Learning communities: the link to recruitment and retention.

    PubMed

    Bassi, Sherry; Polifroni, E Carol

    2005-01-01

    The professional learning community is a strategy to help staff development educators address recruitment and retention and organizational culture. The purpose of this article is to analyze the concept of learning communities and discuss their potential to increase the recruitment and retention of new graduate nurses and returning practitioners to the nursing profession. Incorporating learning communities into the healthcare organization will decrease the number of nurses leaving nursing, foster retention, and thus, enhance recruitment. PMID:15940026

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

    PubMed

    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. PMID:2703893

  6. Uterine Fibroid (Leiomyoma) with Acute Urinary Retention: A Case Series

    PubMed Central

    Jena, Saubhagya Kumar; Naik, Monalisha; Ray, Lipsa; Behera, Satyanarayan

    2016-01-01

    Uterine leiomyomas are an extremely rare cause of acute urinary retention in women. The delay in diagnosing uterine leiomyomas presenting with acute urinary retention further complicates the management. The rarity of the condition makes it difficult to plan either prospective or retrospective trials. Hence, most of the evidence comes from case reports or series. We report a case series of acute urinary retention in women with uterine leiomyomas and discuss the pathophysiology, diagnosis and management options. PMID:27190903

  7. Effects of Globally Waste Disturbing Activities on Gas Generation, Retention, and Release in Hanford Waste Tanks

    SciTech Connect

    Stewart, Charles W.; Fountain, Matthew S.; Huckaby, James L.; Mahoney, Lenna A.; Meyer, Perry A.; Wells, Beric E.

    2005-08-02

    Various operations are authorized in Hanford single- and double-shell tanks that disturb all or a large fraction of the waste. These globally waste-disturbing activities have the potential to release a large fraction of the retained flammable gas and to affect future gas generation, retention, and release behavior. This report presents analyses of the expected flammable gas release mechanisms and the potential release rates and volumes resulting from these activities. The background of the flammable gas safety issue at Hanford is summarized, as is the current understanding of gas generation, retention, and release phenomena. Considerations for gas monitoring and assessment of the potential for changes in tank classification and steady-state flammability are given.

  8. The effect of hydrate saturation on water retention curves in hydrate-bearing sediments

    NASA Astrophysics Data System (ADS)

    Mahabadi, Nariman; Zheng, Xianglei; Jang, Jaewon

    2016-05-01

    The experimental measurement of water retention curve in hydrate-bearing sediments is critically important to understand the behavior of hydrate dissociation and gas production. In this study, tetrahydrofuran (THF) is selected as hydrate former. The pore habit of THF hydrates is investigated by visual observation in a transparent micromodel. It is confirmed that THF hydrates are not wetting phase on the quartz surface of the micromodel and occupy either an entire pore or part of pore space resulting in change in pore size distribution. And the measurement of water retention curves in THF hydrate-bearing sediments with hydrate saturation ranging from Sh = 0 to Sh = 0.7 is conducted for excess water condition. The experimental results show that the gas entry pressure and the capillary pressure increase with increasing hydrate saturation. Based on the experimental results, fitting parameters for van Genuchten equation are suggested for different hydrate saturation conditions.

  9. Human memory retention and recall processes. A review of EEG and fMRI studies.

    PubMed

    Amin, Hafeezullah; Malik, Aamir S

    2013-10-01

    Human memory is an important concept in cognitive psychology and neuroscience. Our brain is actively engaged in functions of learning and memorization. Generally, human memory has been classified into 2 groups: short-term/working memory, and long-term memory. Using different memory paradigms and brain mapping techniques, psychologists and neuroscientists have identified 3 memory processes: encoding, retention, and recall. These processes have been studied using EEG and functional MRI (fMRI) in cognitive and neuroscience research. This study reviews previous research reported for human memory processes, particularly brain behavior in memory retention and recall processes with the use of EEG and fMRI. We discuss issues and challenges related to memory research with EEG and fMRI techniques. PMID:24141456

  10. Rayleigh-Taylor Instability within Sediment Layers Due to Gas Retention: Preliminary Theory and Experiments

    SciTech Connect

    Gauglitz, Phillip A.; Wells, Beric E.; Buchmiller, William C.; Rassat, Scot D.

    2013-03-21

    In Hanford underground waste storage tanks, a typical waste configuration is settled beds of waste particles beneath liquid layers. The settled beds are typically composed of layers, and these layers can have different physical and chemical properties. One postulated configuration within the settled bed is a less-dense layer beneath a more-dense layer. The different densities can be a result of different gas retention in the layers or different degrees of settling and compaction in the layers. This configuration can experience a Rayleigh-Taylor (RT) instability where the less dense lower layer rises into the upper layer. Previous studies of gas retention and release have not considered potential buoyant motion within a settle bed of solids. The purpose of this report is to provide a review of RT instabilities, discuss predictions of RT behavior for sediment layers, and summarize preliminary experimental observations of RT instabilities in simulant experiments.

  11. Time-dependent effects of posttraining intrahippocampal injections of corticosterone on retention of appetitive learning tasks in mice.

    PubMed

    Micheau, J; Destrade, C; Soumireu-Mourat, B

    1984-10-30

    In previous studies we suggested that corticosterone may modulate hippocampal functioning during memory formation. To test this assumption, we studied the effects of posttrial administration of corticosterone (1 microgram) injected bilaterally in the hippocampus. The treatment was applied at different time intervals after the learning session and the retention session took place 24 h later. Using appetitive operant conditioning tasks in a Skinner box, we found that the posttrial treatment 1) did not affect the retention of a continuously reinforced schedule, 2) improved the retention of a successive discrimination learning task, and 3) was still effective when given 3 h after the acquisition of this task, but not after 6 h. Taken together, the results suggest that corticosterone modulates the hippocampal mechanisms involved in behavioral suppression during memory formation. PMID:6529972

  12. Conceptual classification model for Sustainable Flood Retention Basins.

    PubMed

    Scholz, Miklas; Sadowski, Adam J

    2009-01-01

    The aim of this paper is to recommend a rapid conceptual classification model for Sustainable Flood Retention Basins (SFRB) used to control runoff in a temperate climate. An SFRB is an aesthetically pleasing retention basin predominantly used for flood protection adhering to sustainable drainage and best management practices. The classification model was developed on the basis of a database of 141 SFRB using the River Rhine catchment in Baden (part of Baden-Württemberg, Germany) as a case study. It is based on an agglomerative cluster analysis and is intended to be used by engineers and scientists to adequately classify the following different types of SFRB: Hydraulic Flood Retention Basin, Traditional Flood Retention Basin, Sustainable Flood Retention Wetland, Aesthetic Flood Retention Wetland, Integrated Flood Retention Wetland and Natural Flood Retention Wetland. The selection of classification variables was supported by a principal component analysis. The identification of SFRB in the data set was based on a Ward cluster analysis of 34 weighted classification variables. Scoring tables were defined to enable the assignment of the six SFRB definitions to retention basins in the data set. The efficiency of these tables was based on a scoring system which gave the conceptual model for the example case study sites an overall efficiency of approximately 60% (as opposed to 17% by chance). This conceptual classification model should be utilized to improve communication by providing definitions for SFRB types. The classification definitions are likely to be applicable for other regions with both temperate oceanic and temperate continental climates. PMID:18280029

  13. Mechanical retention versus bonding of amalgam and gallium alloy restorations.

    PubMed

    Eakle, W S; Staninec, M; Yip, R L; Chavez, M A

    1994-10-01

    The retention of amalgam and gallium alloy restorations in proximal box forms was measured in vitro, and three different adhesives to conventional undercuts were compared. For control, restorations were placed without undercuts or adhesives. No significant difference was found between amalgam and gallium alloys with each of the five methods of retention used. Alloys placed without retention or adhesives were significantly less retentive than all other groups. When Tytin alloy was used, no difference was found in retention among the restorations retained with Panavia or All-Bond adhesive or an occlusal dovetail and retention grooves, but Amalgambond adhesive was less retentive than all three of these methods. When gallium alloy was used, both Panavia and All-Bond adhesive were more retentive than undercuts, but the effect of Amalgambond adhesive was more retentive than undercuts, but the effect of Amalgambond adhesive was comparable to that of undercuts. The results of this study indicate that adhesives could be used in place of traditional undercuts to retain amalgam and gallium alloys, thus saving a considerable amount of tooth structure. PMID:7990038

  14. Retention Indices for Frequently Reported Compounds of Plant Essential Oils

    NASA Astrophysics Data System (ADS)

    Babushok, V. I.; Linstrom, P. J.; Zenkevich, I. G.

    2011-12-01

    Gas chromatographic retention indices were evaluated for 505 frequently reported plant essential oil components using a large retention index database. Retention data are presented for three types of commonly used stationary phases: dimethyl silicone (nonpolar), dimethyl silicone with 5% phenyl groups (slightly polar), and polyethylene glycol (polar) stationary phases. The evaluations are based on the treatment of multiple measurements with the number of data records ranging from about 5 to 800 per compound. Data analysis was limited to temperature programmed conditions. The data reported include the average and median values of retention index with standard deviations and confidence intervals.

  15. What the Regulations Say about Record Retention and Imaged Documents.

    ERIC Educational Resources Information Center

    Conard, Linda, Comp.

    2001-01-01

    Presents the federal government's general provisions on student financial aid record retention and the Federal Perkins Loan program's procedures for maintaining promissory notes and repayment schedules. (EV)

  16. A Discussion of SY-101 Crust Gas Retention and Release Mechanisms

    SciTech Connect

    SD Rassat; PA Gauglitz; SM Caley; LA Mahoney; DP Mendoza

    1999-02-23

    The flammable gas hazard in Hanford waste tanks was made an issue by the behavior of double-shell Tank (DST) 241-SY-101 (SY-101). Shortly after SY-101 was filled in 1980, the waste level began rising periodically, due to the generation and retention of gases within the slurry, and then suddenly dropping as the gases were released. An intensive study of the tank's behavior revealed that these episodic releases posed a safety hazard because the released gas was flammable, and, in some cases, the volume of gas released was sufficient to exceed the lower flammability limit (LFL) in the tank headspace (Allemann et al. 1993). A mixer pump was installed in SY-101 in late 1993 to prevent gases from building up in the settled solids layer, and the large episodic gas releases have since ceased (Allemann et al. 1994; Stewart et al. 1994; Brewster et al. 1995). However, the surface level of SY-101 has been increasing since at least 1995, and in recent months the level growth has shown significant and unexpected acceleration. Based on a number of observations and measurements, including data from the void fraction instrument (VFI), we have concluded that the level growth is caused largely by increased gas retention in the floating crust. In September 1998, the crust contained between about 21 and 43% void based on VFI measurements (Stewart et al. 1998). Accordingly, it is important to understand the dominant mechanisms of gas retention, why the gas retention is increasing, and whether the accelerating level increase will continue, diminish or even reverse. It is expected that the retained gas in the crust is flammable, with hydrogen as a major constituent. This gas inventory would pose a flammable gas hazard if it were to release suddenly. In May 1997, the mechanisms of bubble retention and release from crust material were the subject of a workshop. The evaluation of the crust and potential hazards assumed a more typical void of roughly 15% gas. It could be similar to percolati

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

    SciTech Connect

    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.

  18. Experimental designs for modeling retention patterns and separation efficiency in analysis of fatty acid methyl esters by gas chromatography-mass spectrometry.

    PubMed

    Skartland, Liv Kjersti; Mjøs, Svein A; Grung, Bjørn

    2011-09-23

    The retention behavior of components analyzed by chromatography varies with instrumental settings. Being able to predict how changes in these settings alter the elution pattern is useful, both with regards to component identification, as well as with regards to optimization of the chromatographic system. In this work, it is shown how experimental designs can be used for this purpose. Different experimental designs for response surface modeling of the separation of fatty acid methyl esters (FAME) as function of chromatographic conditions in GC have been evaluated. Full factorial, central composite, Doehlert and Box-Behnken designs were applied. A mixture of 38 FAMEs was separated on a polar cyanopropyl substituted polysilphenylene-siloxane phase capillary column. The temperature gradient, the start temperature of the gradient, and the carrier gas velocity were varied in the experiments. The modeled responses, as functions of chromatographic conditions, were retention time, retention indices, peak widths, separation efficiency and resolution between selected peak pairs. The designs that allowed inclusion of quadratic terms among the predictors performed significantly better than factorial design. Box-Behnken design provided the best results for prediction of retention, but the differences between the central composite, Doehlert and Box-Behnken designs were small. Retention indices could be modeled with much better accuracy than retention times. However, because the errors of predicted tR of closely eluting peaks were highly correlated, models of resolution (Rs) that were based on retention time had errors in the same range as corresponding models based on ECL. PMID:21851946

  19. Etude des effets du martelage repetitif sur les contraintes residuelles

    NASA Astrophysics Data System (ADS)

    Hacini, Lyes

    L'assemblage par soudage peut engendrer des contraintes residuelles. Ces contraintes provoquent des fissurations prematurees et un raccourcissement de la duree de vie des composants. Dans ce contexte, le martelage robotise est utilise pour relaxer ces contraintes residuelles. Trois volets sont presentes: le premier est l'evaluation des effets des impacts unitaires repetes sur le champ de contraintes developpe dans des plaques d'acier inoxydable austenitique 304L vierges ou contenant des contraintes residuelles initiales. Dans la deuxieme partie de ce projet, le martelage est applique grace au robot SCOMPI. Les contraintes residuelles induites et relaxees par martelage sont ensuite mesurees par la methode des contours, qui a ete adaptee a cet effet. Dans la troisieme partie, le martelage est modelise par la methode des elements finis. Un modele axisymetrique developpe grace au logiciel ANSYS permet de simuler des impacts repetes d'un marteau elastique sur une plaque ayant un comportement elastoplastique.

  20. Predictors of clinically significant weight loss and participant retention in an insurance-sponsored community-based weight management program.

    PubMed

    Abildso, Christiaan G; Zizzi, Sam; Fitzpatrick, Sean J

    2013-07-01

    Health insurance providers are a logical partner in providing third-party payment for behavioral weight loss programming, but little evidence of predictors of improved outcomes or retention in large, insurance-sponsored lifestyle programming is available. The purpose was to determine predictors of weight loss and retention in an insurance-sponsored, community-based weight management program. Current and former participants (N = 2,106) were recruited to complete a program evaluation survey. Respondents' survey and objective outcome data (n = 766) were analyzed using logistic regression procedures to understand the factors predictive of clinically-significant (5%) weight loss and program retention (>6 months). Clinically significant weight loss was predicted by completing more than 6 months of the program, positive ratings of staff interaction, and social support from friends on success. Ratings of positive impact of site hours of operation, nurse calls, and availability of safe places to be active and feeling comfortable at the site were predictive of program retention. Modifiable intervention, social factors, and site-level factors were predictive of clinically significant weight loss and program retention, providing fodder for further study and dissemination to current providers and to a broader network of health promotion professionals. PMID:23075503

  1. Scoring Dawg Core Breakoff and Retention Mechanism

    NASA Technical Reports Server (NTRS)

    Badescu, Mircea; Sherrit, Stewart; Bar-Cohen, Yoseph; Bao, Xiaoqi; Backes, Paul G.

    2011-01-01

    This novel core break-off and retention mechanism consists of a scoring dawg controlled by a set of two tubes (a drill tube and an inner tube). The drill tube and the inner tube have longitudinal concentric holes. The solution can be implemented in an eccentric tube configuration as well where the tubes have eccentric longitudinal holes. The inner tube presents at the bottom two control surfaces for controlling the orientation of the scoring dawg. The drill tube presents a sunk-in profile on the inside of the wall for housing the scoring dawg. The inner tube rotation relative to the drill tube actively controls the orientation of the scoring dawg and hence its penetration and retrieval from the core. The scoring dawg presents a shaft, two axially spaced arms, and a tooth. The two arms slide on the control surfaces of the inner tube. The tooth, when rotated, can penetrate or be extracted from the core. During drilling, the two tubes move together maintaining the scoring dawg completely outside the core. After the desired drilling depth has been reached the inner tube is rotated relative to the drill tube such that the tooth of the scoring dawg moves toward the central axis. By rotating the drill tube, the scoring dawg can score the core and so reduce its cross sectional area. The scoring dawg can also act as a stress concentrator for breaking the core in torsion or tension. After breaking the core, the scoring dawg can act as a core retention mechanism. For scoring, it requires the core to be attached to the rock. If the core is broken, the dawg can be used as a retention mechanism. The scoring dawg requires a hard-tip insert like tungsten carbide for scoring hard rocks. The relative rotation of the two tubes can be controlled manually or by an additional actuator. In the implemented design solution the bit rotation for scoring was in the same direction as the drilling. The device was tested for limestone cores and basalt cores. The torque required for breaking the

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

    PubMed

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

    2016-05-01

    Two experiments were designed to compare two symbolic rehearsal refresher interventions (imaginary practice, a hidden introspective process) and investigate the role of retentivity in skill retention. Retentivity is investigated as the ability to memorise and reproduce information and associations that were learned a short time ago. Both experiments comprised initial training (week 1), a symbolic rehearsal for the experimental group (week 2) and a retention assessment (week 3). In the first study, the experimental group received a symbolic rehearsal, while the control group received no rehearsal. In the second study, the experimental group received the same symbolic rehearsal used in study 1, enhanced with rehearsal tasks addressing human-computer interaction. The results showed that both symbolic rehearsal interventions were equally likely to mitigate skill decay. The retentivity showed medium to high correlations with skill retention in both studies, and the results suggest that subjects high in retentivity benefit more from a symbolic rehearsal refresher intervention. Practitioner Summary: Skill decay becomes a problem in situations in which jobs require the correct mastery of non-routine situations. Two experimental studies with simulated process control tasks showed that symbolic rehearsal and retentivity can significantly mitigate skill decay and that subjects higher in retentivity benefit more from refresher interventions. PMID:26442562

  3. Novel word retention in bilingual and monolingual speakers

    PubMed Central

    Kan, Pui Fong; Sadagopan, Neeraja

    2014-01-01

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

  4. Estimating soil water retention using soil component additivity model

    NASA Astrophysics Data System (ADS)

    Zeiliger, A.; Ermolaeva, O.; Semenov, V.

    2009-04-01

    Soil water retention is a major soil hydraulic property that governs soil functioning in ecosystems and greatly affects soil management. Data on soil water retention are used in research and applications in hydrology, agronomy, meteorology, ecology, environmental protection, and many other soil-related fields. Soil organic matter content and composition affect both soil structure and adsorption properties; therefore water retention may be affected by changes in soil organic matter that occur because of both climate change and modifications of management practices. Thus, effects of organic matter on soil water retention should be understood and quantified. Measurement of soil water retention is relatively time-consuming, and become impractical when soil hydrologic estimates are needed for large areas. One approach to soil water retention estimation from readily available data is based on the hypothesis that soil water retention may be estimated as an additive function obtained by summing up water retention of pore subspaces associated with soil textural and/or structural components and organic matter. The additivity model and was tested with 550 soil samples from the international database UNSODA and 2667 soil samples from the European database HYPRES containing all textural soil classes after USDA soil texture classification. The root mean square errors (RMSEs) of the volumetric water content estimates for UNSODA vary from 0.021 m3m-3 for coarse sandy loam to 0.075 m3m-3 for sandy clay. Obtained RMSEs are at the lower end of the RMSE range for regression-based water retention estimates found in literature. Including retention estimates of organic matter significantly improved RMSEs. The attained accuracy warrants testing the 'additivity' model with additional soil data and improving this model to accommodate various types of soil structure. Keywords: soil water retention, soil components, additive model, soil texture, organic matter.

  5. Formation and retention of methane in coal. Final report

    SciTech Connect

    Hucka, V.J.; Bodily, D.M.; Huang, H.

    1992-05-15

    The formation and retention of methane in coalbeds was studied for ten Utah coal samples, one Colorado coal sample and eight coal samples from the Argonne Premium Coal Sample Bank.Methane gas content of the Utah and Colorado coals varied from zero to 9 cm{sup 3}/g. The Utah coals were all high volatile bituminous coals. The Colorado coal was a gassy medium volatile bituminous coal. The Argonne coals cover a range or rank from lignite to low volatile bituminous coal and were used to determine the effect of rank in laboratory studies. The methane content of six selected Utah coal seams and the Colorado coal seam was measured in situ using a special sample collection device and a bubble desorbometer. Coal samples were collected at each measurement site for laboratory analysis. The cleat and joint system was evaluated for the coal and surrounding rocks and geological conditions were noted. Permeability measurements were performed on selected samples and all samples were analyzed for proximate and ultimate analysis, petrographic analysis, {sup 13}C NMR dipolar-dephasing spectroscopy, and density analysis. The observed methane adsorption behavior was correlated with the chemical structure and physical properties of the coals.

  6. Solute transport and retention in three-dimensional fracture networks

    NASA Astrophysics Data System (ADS)

    Cvetkovic, Vladimir; Frampton, Andrew

    2012-02-01

    Resolving the hydrodynamic control of retention is an important step in predictive modeling of transport of sorbing tracers in fractured rock. The statistics of the transport resistance parameter β [T/L] and the related effective active specific surface area sf [1/L] are studied in a crystalline rock volume on a 100 m scale. Groundwater flow and advective transport are based on generic boundary conditions and realistic discrete fracture networks inferred from the Laxemar site, southeast Sweden. The overall statistics of β are consistent with statistics of the water residence time τ; the moments of β vary linearly with distance, at least up to 100 m. The correlation between log τ and log β is predominantly linear, however, there is significant dispersion; the parameter sf strongly depends on the assumed hydraulic law (theoretical cubic or empirical quadratic). Fast and slow trajectories/segments in the network determine the shape of the β distribution that cannot be reproduced by infinitely divisible model over the entire range; the low value range and median can be reproduced reasonably well with the tempered one-sided stable density using the exponent in the range 0.35-0.7. The low percentiles of the β distribution seems to converge to a Fickian type of behavior from a 50 to 100 m scale.

  7. Gender-related behavior in women exposed prenatally to diethylstilbestrol.

    PubMed Central

    Newbold, R R

    1993-01-01

    Accumulating evidence in experimental animals over the past three decades suggests that mammalian brain development and differentiation of the central nervous system are influenced by perinatal exposure to sex hormones. Hence, changes in human behavioral patterns may be associated with prenatal exposure to estrogenic substances such as diethylstilbestrol (DES). This paper reviews relevant studies from a series of laboratories and finds that no clear-cut differences can be demonstrated to date between unexposed and DES-exposed women in gender-related behavior, although the physical and psychological impact of the problems associated with exposure to DES are well documented. If both prenatal and postnatal influences such as social, economic, and environmental factors are taken into consideration, individual variation is more apparent than differences in gender-related behavior between unexposed and DES-exposed women. In summary, gender-related behavior is determined by a complex array of interacting factors, and prenatal influences are only one of many developmental events. More studies are needed using larger populations with carefully controlled selection criteria to suggest a direct role of prenatal DES exposure on subsequent gender-related behavior. Images p208-a PMID:8404755

  8. Volatile species retention during metallic fuel casting

    NASA Astrophysics Data System (ADS)

    Fielding, Randall S.; Porter, Douglas L.

    2013-10-01

    Metallic nuclear fuels are candidate transmutation fuel forms for advanced fuel cycles. Through the operation of the Experimental Breeder Reactor II metallic nuclear fuels have been shown to be robust and easily manufactured. However, concerns have been raised concerning loss of americium during the casting process because of its high vapor pressure. In order to address these concerns a gaseous diffusion model was developed and a series of experiments using both manganese and samarium as surrogates for americium were conducted. The modeling results showed that volatility losses can be controlled to essentially no losses with a modest overpressure. Experimental results also showed volatile species retention down to no detectable losses through overpressure, and although the loss values varied from the model results the same trend was seen. Based on these results it is very probable that americium losses through volatility can be controlled to no detectable losses through application of a modest overpressure during casting.

  9. Volatile Species Retention During Metallic Fuel Casting

    SciTech Connect

    Randall S. Fielding; Douglas L. Proter

    2013-10-01

    Metallic nuclear fuels are candidate transmutation fuel forms for advanced fuel cycles. Through the operation of the Experimental Breeder Reactor II metallic nuclear fuels have been shown to be robust and easily manufactured. However, concerns have been raised concerning loss of americium during the casting process because of its high vapor pressure. In order to address these concerns a gaseous diffusion model was developed and a series of experiments using both manganese and samarium as surrogates for americium were conducted. The modeling results showed that volatility losses can be controlled to essentially no losses with a modest overpressure. Experimental results also showed volatile species retention down to no detectable losses through overpressure, although the loss values varied from the model results the same trend was seen. Bases on these results it is very probably that americium losses through volatility can be controlled to no detectable losses through application of a modest overpressure during casting.

  10. [Acute cardiovascular disease and job retention].

    PubMed

    Fantoni-Quinton, Sophie; Tellart, Anne-Sophie; Cambier-Langrand, Evodie; Fassier, Jean Baptiste; Mounier-Vehier, Claire

    2016-05-01

    Since it allows a better quality of life, return to work must be considered ever since the early stages of the health care pathway following a cardiovascular disease. Seeing the occupational physician beforehand, so as to anticipate the return to work, is crucial. Dialogue between cardiologists, general practitioners and occupational physician, still observing medical confidentiality, must allow a better quality of return to work. Being recognized as a handicapped worker is a key element in the prevention of socio-professional exclusion. Even when dealing with long sick leave, permanent functional injuries or job loss, guiding the patients towards the appropriate person can improve return to work and job retention in the long term. PMID:27021479

  11. Recruitment and Retention of LGBTIQ Astronomers

    NASA Astrophysics Data System (ADS)

    Dixon, William Van Dyke

    2012-01-01

    While lesbian, gay, bisexual, transgender, intersex, or questioning (LGBTIQ) astronomers face many of the same workplace challenges as women and racial/ethnic minorities, from implicit bias to overt discrimination, other challenges are unique to this group. An obvious example is the absence at many institutions of health insurance and other benefits for the same-sex domestic partners of their employees. More subtle is the psychological toll paid by LGBTIQ astronomers who remain "in the closet," self-censoring every statement about their personal lives. Paradoxically, the culture of the physical sciences, in which sexuality, gender identity, and gender expression are considered irrelevant, can discourage their discussion, further isolating LGBTIQ researchers. Addressing these challenges is not just a matter of fairness; it is an essential tool in the recruitment and retention of the brightest researchers and in assuring their productivity. We will discuss these issues and what individuals and departments can to make their institutions more welcoming to their LGBTIQ colleagues.

  12. 228Th retention and dosimetry in beagles.

    PubMed

    Lloyd, R D; Jones, C W; Mays, C W; Atherton, D R; Bruenger, F W; Taylor, G N

    1984-06-01

    Total-body and skeletal retention of 228Th were determined in a group of 104 young adult male and female beagles for about the first 7 years after the injection of 0.00159 to 2.76 muCi/kg. Ratios of 224Ra / 228Th , 212Pb / 228Th , and 212Bi / 228Th in the skeleton and in soft tissues of 20 beagles were measured as a function of time after injection. A humerus, femur, and ulna from 20 dogs dying 7 to 554 days after injection were sectioned, and the 228Th concentration was obtained for each piece. Percentage biological retention in the skeleton of 228Th at t days after injection could be described as 68.1 e-0. 000180t . Ratios of daughter-to-parent activity in soft tissue showed no definite trend with dose level or time and averaged Ra/Th = 0.56, Pb/Th = 0.83, and Bi/Th = 0.91, whereas the ratios for the skeleton varied with both dose level and time. Ratios of activity in the skeleton from lowest to highest dose level after 2 years following injection ranged between Ra/Th = 0.88 to 0.95, Pb/Th = 0.78 to 0.92, and Bi/Th = 0.77 to 0.90. Retained 228Th was deposited most heavily in parts of the skeleton with much trabecular bone, much bone surface area, and high bone remodeling rates. No changes in this deposition pattern could be discerned during the 554 days over which the measurements of sectioned long bones were made. PMID:6427842

  13. Small scale retentive structures and Dinophysis

    NASA Astrophysics Data System (ADS)

    Xie, Hongqin; Lazure, Pascal; Gentien, Patrick

    2007-01-01

    Despite its rarity, Dinophysis acuminata is in terms of economic impact, the first toxic algal species along the coasts of Western Europe. It is observed at low levels (< 20 cell l - 1 ) all the year round but toxic events occur mainly in late spring and summer. D. acuminata ecophysiology is largely unknown due to the inability to culture it. Therefore, standard biomass models based on inorganic nutrition are largely inadequate. Presently, any progress in describing the conditions of population growth of this species will be a step forward to prediction of harmful events at the coast. This species has been observed at increased, albeit low cell densities in retentive eddies located in pycnocline layers. A concentration build-up of one species results from the balance between growth and loss processes, one of the latter being dispersal. The scales of interest for a D. acuminata population are of the order of 10 nautical miles on the horizontal and duration of 10 days, for a reported achievable growth rate of 0.6 day - 1 . A three dimensional (3D) hydrodynamical model of the Bay of Biscay has been elaborated to reproduce hydrological structures over the last decade. We attempt here to relate the existence of retentive structures revealed from simulations under realistic forcing conditions and the toxic coastal events recorded in the 10-year time series of the French plankton monitoring network database. The eddies in the coastal area appear to be directly related with the Dinophysis coastal events and they may be a potential effective tool to predict those.

  14. NASA records retention schedules: Procedures governing the retention, retirement, and destruction of agency records

    NASA Technical Reports Server (NTRS)

    1994-01-01

    This handbook sets forth the minimum retention periods of official records of NASA. Its provisions are applicable to NASA Headquarters and all field installations. This revised edition has been correlated to the 'NASA Uniform Files Index (UFI) (NHB 1442.1B), the General Records Schedules' produced by the National Archives and Records Administration (NARA), and has been enlarged in scope to cover Privacy Act Systems of Records and record series previously omitted. Guidance is provided in the areas of record retirement, transfer, and retrieval from Federal Record Centers (FRC) and disposal actions. Included are provisions for making changes to these schedules by addition of new items or revision of current items. The NASA Records Retention Schedules (NRRS) were approved for NASA use by NARA, the General Services Administration, and the General Accounting Office.

  15. 27 CFR 20.265 - Retention of invoices.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Retention of invoices. 20....265 Retention of invoices. (a) Any person required to keep records under this part shall retain copies of invoices which will enable appropriate TTB officers to readily obtain the details regarding:...

  16. Retention in Special Education Teachers in Georgia: A Phenomenological Approach

    ERIC Educational Resources Information Center

    Jackson, Arndra N.

    2012-01-01

    The purpose of this qualitative study using a phenomenological approach was to identify and examine factors influencing the retention rate of special education teachers in rural and urban schools in middle Georgia. Provided in this study are factors that are related to retention in special education teachers. Semistructured interviews were used to…

  17. Retention-Attrition in the Nineties. ERIC Digest.

    ERIC Educational Resources Information Center

    Brawer, Florence B.

    Concern about retention and attrition rates in higher education have increased over the years and efforts to identify and treat potential dropouts have grown considerably. Studies investigating the retention and attrition of community college students have found specific characteristics related to outcomes, including full- or part-time attendance,…

  18. Know when to Hold 'Em: Data Retention Policies

    ERIC Educational Resources Information Center

    Johnson, Jason

    2007-01-01

    While the need for a data retention policy is rapidly becoming clear to schools, little guidance is available for crafting one. Most schools depend on backup and recovery plans that generally focus on individual servers or devices. However, retention policies also need to focus on the type of data contained on those servers and how it will be…

  19. Effects of Targeted Sales Messages on Subscription Sales and Retention.

    ERIC Educational Resources Information Center

    Gamst, Glenn; And Others

    1987-01-01

    Investigates the effects of targeted sales messages on newspaper subscription sales and retention by combining two large research projects--a demographic market segmentation scheme, and a readership-lifestyle survey. Proposes that the content of sales messages influences new subscriptions but does not affect retention. (MM)

  20. 27 CFR 20.265 - Retention of invoices.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Retention of invoices. 20.265 Section 20.265 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Records and Reports § 20.265 Retention of invoices. (a)...

  1. 47 CFR 2.955 - Retention of records.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Retention of records. 2.955 Section 2.955 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Equipment Authorization Procedures Verification § 2.955 Retention of records. (a) For each equipment subject...

  2. 44 CFR 321.5 - Retention of industrial facilities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 44 Emergency Management and Assistance 1 2010-10-01 2010-10-01 false Retention of industrial..., DEPARTMENT OF ENERGY, MARITIME ADMINISTRATION) § 321.5 Retention of industrial facilities. (a) Industrial..., shall be retained in the Industrial reserves (National Industrial Reserve, Departmental...

  3. 44 CFR 321.5 - Retention of industrial facilities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 44 Emergency Management and Assistance 1 2012-10-01 2011-10-01 true Retention of industrial..., DEPARTMENT OF ENERGY, MARITIME ADMINISTRATION) § 321.5 Retention of industrial facilities. (a) Industrial..., shall be retained in the Industrial reserves (National Industrial Reserve, Departmental...

  4. 44 CFR 321.5 - Retention of industrial facilities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 44 Emergency Management and Assistance 1 2013-10-01 2013-10-01 false Retention of industrial..., DEPARTMENT OF ENERGY, MARITIME ADMINISTRATION) § 321.5 Retention of industrial facilities. (a) Industrial..., shall be retained in the Industrial reserves (National Industrial Reserve, Departmental...

  5. 44 CFR 321.5 - Retention of industrial facilities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 44 Emergency Management and Assistance 1 2014-10-01 2014-10-01 false Retention of industrial..., DEPARTMENT OF ENERGY, MARITIME ADMINISTRATION) § 321.5 Retention of industrial facilities. (a) Industrial..., shall be retained in the Industrial reserves (National Industrial Reserve, Departmental...

  6. 44 CFR 321.5 - Retention of industrial facilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 44 Emergency Management and Assistance 1 2011-10-01 2011-10-01 false Retention of industrial..., DEPARTMENT OF ENERGY, MARITIME ADMINISTRATION) § 321.5 Retention of industrial facilities. (a) Industrial..., shall be retained in the Industrial reserves (National Industrial Reserve, Departmental...

  7. 32 CFR 536.69 - Retention of file.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Retention of file. 536.69 Section 536.69 National... UNITED STATES Investigation and Processing of Claims § 536.69 Retention of file. After final action has been taken, the settlement authority will retain the file until at least one month after either...

  8. 4 CFR 5.2 - Grade and pay retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 4 Accounts 1 2010-01-01 2010-01-01 false Grade and pay retention. 5.2 Section 5.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM COMPENSATION § 5.2 Grade and pay retention. (a) Change of... employee's position for all purposes (including pay and pay administration, retirement, life insurance...

  9. 4 CFR 5.2 - Grade and pay retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 4 Accounts 1 2011-01-01 2011-01-01 false Grade and pay retention. 5.2 Section 5.2 Accounts GOVERNMENT ACCOUNTABILITY OFFICE PERSONNEL SYSTEM COMPENSATION § 5.2 Grade and pay retention. (a) Change of... employee's position for all purposes (including pay and pay administration, retirement, life insurance...

  10. 5 CFR 532.419 - Grade and pay retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Grade and pay retention. 532.419 Section 532.419 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PREVAILING RATE SYSTEMS Pay Administration § 532.419 Grade and pay retention. (a) In accordance with section...

  11. 5 CFR 532.419 - Grade and pay retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Grade and pay retention. 532.419 Section 532.419 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PREVAILING RATE SYSTEMS Pay Administration § 532.419 Grade and pay retention. (a) In accordance with section...

  12. Student Retention and Graduation, University System of Georgia.

    ERIC Educational Resources Information Center

    University System of Georgia, Atlanta. Office of Research and Planning.

    Describing outcomes related to student retention and graduation in the University System of Georgia, this six-part report discusses definitions and assumptions pertaining to retention and compares success rates for black, white, developmental studies, and regularly-admitted freshmen students in USG senior and two-year colleges. Section 1 provides…

  13. 13 CFR 120.861 - Job creation or retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 13 Business Credit and Assistance 1 2014-01-01 2014-01-01 false Job creation or retention. 120.861... Company Loan Program (504) Project Economic Development Goals § 120.861 Job creation or retention. A Project must create or retain one Job Opportunity per an amount of 504 loan funding that will be...

  14. 13 CFR 120.861 - Job creation or retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 13 Business Credit and Assistance 1 2012-01-01 2012-01-01 false Job creation or retention. 120.861... Company Loan Program (504) Project Economic Development Goals § 120.861 Job creation or retention. A Project must create or retain one Job Opportunity per an amount of 504 loan funding that will be...

  15. 13 CFR 120.861 - Job creation or retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 13 Business Credit and Assistance 1 2011-01-01 2011-01-01 false Job creation or retention. 120.861... Company Loan Program (504) Project Economic Development Goals § 120.861 Job creation or retention. A Project must create or retain one Job Opportunity per an amount of 504 loan funding that will be...

  16. 13 CFR 120.861 - Job creation or retention.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Job creation or retention. 120.861... Company Loan Program (504) Project Economic Development Goals § 120.861 Job creation or retention. A Project must create or retain one Job Opportunity per an amount of 504 loan funding that will be...

  17. 13 CFR 120.861 - Job creation or retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 13 Business Credit and Assistance 1 2013-01-01 2013-01-01 false Job creation or retention. 120.861... Company Loan Program (504) Project Economic Development Goals § 120.861 Job creation or retention. A Project must create or retain one Job Opportunity per an amount of 504 loan funding that will be...

  18. 47 CFR 2.955 - Retention of records.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 1 2013-10-01 2013-10-01 false Retention of records. 2.955 Section 2.955 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Equipment Authorization Procedures Verification § 2.955 Retention of records. (a) For each equipment subject...

  19. 7 CFR 274.5 - Record retention and forms security.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 4 2013-01-01 2013-01-01 false Record retention and forms security. 274.5 Section 274.5 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM ISSUANCE AND USE OF PROGRAM BENEFITS § 274.5 Record retention and forms security....

  20. 7 CFR 274.5 - Record retention and forms security.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Record retention and forms security. 274.5 Section 274.5 Agriculture Regulations of the Department of Agriculture (Continued) FOOD AND NUTRITION SERVICE, DEPARTMENT OF AGRICULTURE FOOD STAMP AND FOOD DISTRIBUTION PROGRAM ISSUANCE AND USE OF PROGRAM BENEFITS § 274.5 Record retention and forms security....

  1. 12 CFR 1005.13 - Administrative enforcement; record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 8 2014-01-01 2014-01-01 false Administrative enforcement; record retention. 1005.13 Section 1005.13 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION ELECTRONIC FUND TRANSFERS (REGULATION E) General § 1005.13 Administrative enforcement; record retention. (a) Enforcement...

  2. 12 CFR 710.7 - Retention of records.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Retention of records. 710.7 Section 710.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS VOLUNTARY LIQUIDATION § 710.7 Retention of records. (a) The board of directors or liquidating agent shall appoint...

  3. 12 CFR 710.7 - Retention of records.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Retention of records. 710.7 Section 710.7 Banks and Banking NATIONAL CREDIT UNION ADMINISTRATION REGULATIONS AFFECTING CREDIT UNIONS VOLUNTARY LIQUIDATION § 710.7 Retention of records. (a) The board of directors or liquidating agent shall appoint...

  4. A Year-Round Recruitment and Retention Plan.

    ERIC Educational Resources Information Center

    Monetti-Souply, Marta

    Catholic school educators are recognizing the necessity of marketing research for the effective planning of a long-range, proactive recruitment and retention program. A successful plan involves marketing, recruitment and retention, and public relations. Part I of this booklet outlines steps for the initiation of a marketing plan and provides…

  5. 47 CFR 2.955 - Retention of records.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 1 2014-10-01 2014-10-01 false Retention of records. 2.955 Section 2.955 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Equipment Authorization Procedures Verification § 2.955 Retention of records. (a) For each equipment subject...

  6. 12 CFR 230.9 - Enforcement and record retention.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Enforcement and record retention. 230.9 Section 230.9 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM TRUTH IN SAVINGS (REGULATION DD) § 230.9 Enforcement and record retention. (a)...

  7. 12 CFR 230.9 - Enforcement and record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 4 2014-01-01 2014-01-01 false Enforcement and record retention. 230.9 Section 230.9 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM (CONTINUED) TRUTH IN SAVINGS (REGULATION DD) § 230.9 Enforcement and record retention....

  8. 12 CFR 230.9 - Enforcement and record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 4 2012-01-01 2012-01-01 false Enforcement and record retention. 230.9 Section 230.9 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM (CONTINUED) TRUTH IN SAVINGS (REGULATION DD) § 230.9 Enforcement and record retention....

  9. 12 CFR 1030.9 - Enforcement and record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 8 2013-01-01 2013-01-01 false Enforcement and record retention. 1030.9 Section 1030.9 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION TRUTH IN SAVINGS (REGULATION DD) § 1030.9 Enforcement and record retention. (a) Administrative enforcement. Section 270 of the act (12...

  10. 12 CFR 1030.9 - Enforcement and record retention.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 9 2014-01-01 2014-01-01 false Enforcement and record retention. 1030.9 Section 1030.9 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION TRUTH IN SAVINGS (REGULATION DD) § 1030.9 Enforcement and record retention. (a) Administrative enforcement. Section 270 of the act (12...

  11. 12 CFR 230.9 - Enforcement and record retention.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 4 2013-01-01 2013-01-01 false Enforcement and record retention. 230.9 Section 230.9 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM (CONTINUED) TRUTH IN SAVINGS (REGULATION DD) § 230.9 Enforcement and record retention....

  12. 12 CFR 1030.9 - Enforcement and record retention.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 8 2012-01-01 2012-01-01 false Enforcement and record retention. 1030.9 Section 1030.9 Banks and Banking BUREAU OF CONSUMER FINANCIAL PROTECTION TRUTH IN SAVINGS (REGULATION DD) § 1030.9 Enforcement and record retention. (a) Administrative enforcement. Section 270 of the act (12...

  13. Increasing Retention of Main Ideas through Questioning Strategies.

    ERIC Educational Resources Information Center

    Wong, Bernice Y. L.

    1979-01-01

    Results of the study involving 30 learning disabled and 30 normally achieving fifth graders indicated that questions increase the retention of main ideas in learning disabled children; however, questions had little effect on the retention of main ideas in normally achieving children. (SBH)

  14. 49 CFR 1244.6 - Retention of files.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Retention of files. 1244.6 Section 1244.6... PROPERTY-RAILROADS § 1244.6 Retention of files. (a) Subject railroads which submit waybill sample data by... transit waybills, for a minimum period of four years. (b) This file of retained waybills shall...

  15. 27 CFR 20.265 - Retention of invoices.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Retention of invoices. 20.265 Section 20.265 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Records and Reports § 20.265 Retention of invoices. (a)...

  16. 27 CFR 20.265 - Retention of invoices.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Retention of invoices. 20.265 Section 20.265 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS DISTRIBUTION AND USE OF DENATURED ALCOHOL AND RUM Records and Reports § 20.265 Retention of invoices. (a)...

  17. When Retention Is Recommended, What Should Parents Do? ERIC Digest.

    ERIC Educational Resources Information Center

    Robertson, Anne S.

    Each year, many teachers face the problem of where to place children who do not fit into the rest of the class. Retention is an option that is frequently considered for these children. Children considered for retention often have poor academic skills, are small in stature or the youngest in the grade, have moved or been absent frequently, do…

  18. 49 CFR 219.901 - Retention of alcohol testing records.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Retention of alcohol testing records. 219.901... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CONTROL OF ALCOHOL AND DRUG USE Recordkeeping Requirements § 219.901 Retention of alcohol testing records. (a) General requirement. In addition to the records required to...

  19. 49 CFR 219.901 - Retention of alcohol testing records.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Retention of alcohol testing records. 219.901... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CONTROL OF ALCOHOL AND DRUG USE Recordkeeping Requirements § 219.901 Retention of alcohol testing records. (a) General requirement. In addition to the records required to...

  20. 49 CFR 219.901 - Retention of alcohol testing records.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Retention of alcohol testing records. 219.901... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION CONTROL OF ALCOHOL AND DRUG USE Recordkeeping Requirements § 219.901 Retention of alcohol testing records. (a) General requirement. In addition to the records required to...