50/50 Expressional Odds of Retention Signifies the Distinction between Retained Introns and Constitutively Spliced Introns in Arabidopsis thaliana

Directory of Open Access Journals (Sweden)

Rui Mao

2017-10-01

Full Text Available Intron retention, one of the most prevalent alternative splicing events in plants, can lead to introns retained in mature mRNAs. However, in comparison with constitutively spliced introns (CSIs, the relevantly distinguishable features for retained introns (RIs are still poorly understood. This work proposes a computational pipeline to discover novel RIs from multiple next-generation RNA sequencing (RNA-Seq datasets of Arabidopsis thaliana. Using this pipeline, we detected 3,472 novel RIs from 18 RNA-Seq datasets and re-confirmed 1,384 RIs which are currently annotated in the TAIR10 database. We also use the expression of intron-containing isoforms as a new feature in addition to the conventional features. Based on these features, RIs are highly distinguishable from CSIs by machine learning methods, especially when the expressional odds of retention (i.e., the expression ratio of the RI-containing isoforms relative to the isoforms without RIs for the same gene reaches to or larger than 50/50. In this case, the RIs and CSIs can be clearly separated by the Random Forest with an outstanding performance of 0.95 on AUC (the area under a receiver operating characteristics curve. The closely related characteristics to the RIs include the low strength of splice sites, high similarity with the flanking exon sequences, low occurrence percentage of YTRAY near the acceptor site, existence of putative intronic splicing silencers (ISSs, i.e., AG/GA-rich motifs and intronic splicing enhancers (ISEs, i.e., TTTT-containing motifs, and enrichment of Serine/Arginine-Rich (SR proteins and heterogeneous nuclear ribonucleoparticle proteins (hnRNPs.

Retention in HIV care depends on patients' perceptions of the clinic experience.

Science.gov (United States)

Wessinger, Matthew H; Hennink, Monique M; Kaiser, Bonnie N; Mangal, Jed P; Gokhale, Runa H; Ruchin, Lauren; Moanna, Abeer; Rimland, David; Farber, Eugene W; Marconi, Vincent C

2017-10-01

Institutional barriers in HIV primary care settings can contribute substantially to disparities in retention in HIV treatment and HIV-related outcomes. This qualitative study compared the perceptions of clinic experiences of persons living with HIV (PLWH) in a Veterans Affairs HIV primary care clinic setting who were retained in care with the experiences of those who were not retained in care. Qualitative data from 25 in-depth interviews were analyzed to identify facilitators and barriers to retention in HIV care. Results showed that participants not retained in care experienced barriers to retention involving dissatisfaction with clinic wait times, low confidence in clinicians, and customer service concerns. For participants retained in care, patience with procedural issues, confidence in clinicians, and interpersonal connections were factors that enhanced retention despite the fact that these participants recognized the same barriers as those who were not retained in care. These findings can inform interventions aimed at improving retention in HIV care.

“To be or not to be retained … That’s the question!”Retention,self - esteem,self - concept,achievement goalsand grades

Directory of Open Access Journals (Sweden)

Francisco Peixoto

2016-10-01

Full Text Available Keeping students back in the same grade – retention – has always been a controversial issue in Education, with some defending it as a beneficial remedial practice and others arguing against its detrimental effects. This paper undertakes an analysis of this issue, focusing on the differences in student motivation and self-related variables according to their retention related status, and the interrelationship between retention and these variables. The participants were 695 students selected from two cohorts (5th and 7th graders of a larger group of students followed over a three-year project. The students were assigned to four groups according to their retention-related status over time: 1 students with past and recent retention; 2 students with past but no recent retention; 3 students with no past but recent retention; 4 students with no past or recent retention. Measures of achievement goal orientations, self-concept, self-esteem, importance given to school subjects and Grade Point Average (GPA were collected for all students.Repeated measures MANCOVA analyses were carried out showing group differences in self-esteem, academic self-concept, importance attributed to academic competencies, task and avoidance orientation and academic achievement. To attain a deeper understanding of these results and to identify profiles across variables, a cluster analysis based on achievement goals was conducted and four clusters were identified. Students who were retained at the end of the school year are mainly represented in clusters with less adaptive motivational profiles and almost absent from clusters exhibiting more adaptive ones.Findings highlight that retention leaves a significant mark that remains even when students recover academic achievement and retention is in the distant past. This is reflected in the low academic self-concept as well as in the devaluation of academic competencies and in the avoidance orientation which, taken together, can

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

Directory of Open Access Journals (Sweden)

Maryam Memarian

2018-02-01

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

5 CFR 536.307 - Treatment of a retained rate as basic pay for other purposes.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Treatment of a retained rate as basic pay... CIVIL SERVICE REGULATIONS GRADE AND PAY RETENTION Pay Retention § 536.307 Treatment of a retained rate... for accumulated and annual leave under 5 CFR part 550, subpart L; (8) General Schedule pay...

“To be or not to be Retained … That’s the Question!” Retention, Self-esteem, Self-concept, Achievement Goals, and Grades

Science.gov (United States)

Peixoto, Francisco; Monteiro, Vera; Mata, Lourdes; Sanches, Cristina; Pipa, Joana; Almeida, Leandro S.

2016-01-01

Keeping students back in the same grade – retention – has always been a controversial issue in Education, with some defending it as a beneficial remedial practice and others arguing against its detrimental effects. This paper undertakes an analysis of this issue, focusing on the differences in student motivation and self-related variables according to their retention related status, and the interrelationship between retention and these variables. The participants were 695 students selected from two cohorts (5th and 7th graders) of a larger group of students followed over a 3-year project. The students were assigned to four groups according to their retention-related status over time: (1) students with past and recent retention; (2) students with past but no recent retention; (3) students with no past but recent retention; (4) students with no past or recent retention. Measures of achievement goal orientations, self-concept, self-esteem, importance given to school subjects and Grade Point Average (GPA) were collected for all students. Repeated measures MANCOVA analyses were carried out showing group differences in self-esteem, academic self-concept, importance attributed to academic competencies, task and avoidance orientation and academic achievement. To attain a deeper understanding of these results and to identify profiles across variables, a cluster analysis based on achievement goals was conducted and four clusters were identified. Students who were retained at the end of the school year are mainly represented in clusters with less adaptive motivational profiles and almost absent from clusters exhibiting more adaptive ones. Findings highlight that retention leaves a significant mark that remains even when students recover academic achievement and retention is in the distant past. This is reflected in the low academic self-concept as well as in the devaluation of academic competencies and in the avoidance orientation which, taken together, can undermine

Novel word retention in sequential bilingual children.

Science.gov (United States)

Kan, Pui Fong

2014-03-01

Children's ability to learn and retain new words is fundamental to their vocabulary development. This study examined word retention in children learning a home language (L1) from birth and a second language (L2) in preschool settings. Participants were presented with sixteen novel words in L1 and in L2 and were tested for retention after either a 2-month or a 4-month delay. Results showed that children retained more words in L1 than in L2 for both of the retention interval conditions. In addition, children's word retention was associated with their existing language knowledge and their fast-mapping performance within and across language. The patterns of association, however, were different between L1 and L2. These findings suggest that children's word retention might be related to the interactions of various components that are operating within a dynamic system.

Differentiating the role of lithium and oxygen in retaining deuterium on lithiated graphite plasma-facing components

Energy Technology Data Exchange (ETDEWEB)

Taylor, C. N. [Fusion Safety Program, Idaho National Laboratory, P.O. Box 1625-7113, Idaho Falls, Idaho 83415 (United States); School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States); Allain, J. P. [School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States); Department of Nuclear, Plasma and Radiological Engineering, University of Illinois at Urbana-Champaign, Illinois 61801 (United States); Luitjohan, K. E. [School of Nuclear Engineering, Purdue University, 400 Central Drive, West Lafayette, Indiana 47907 (United States); Krstic, P. S. [Institute for Advanced Computational Science, Stony Brook University, New York 11794 (United States); Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States); TheoretiK, Knoxville, Tennessee 379XX (United States); Dadras, J. [Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37996 (United States); Department of Chemistry and Biochemistry, University of California Los Angeles, Los Angeles, California 90095 (United States); Skinner, C. H. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2014-05-15

Laboratory experiments have been used to investigate the fundamental interactions responsible for deuterium retention in lithiated graphite. Oxygen was found to be present and play a key role in experiments that simulated NSTX lithium conditioning, where the atomic surface concentration can increase to >40% when deuterium retention chemistry is observed. Quantum-classical molecular dynamic simulations elucidated this oxygen-deuterium effect and showed that oxygen retains significantly more deuterium than lithium in a simulated matrix with 20% lithium, 20% oxygen, and 60% carbon. Simulations further show that deuterium retention is even higher when lithium is removed from the matrix. Experiments artificially increased the oxygen content in graphite to ∼16% and then bombarded with deuterium. X-ray photoelectron spectroscopy showed depletion of the oxygen and no enhanced deuterium retention, thus demonstrating that lithium is essential in retaining the oxygen that thereby retains deuterium.

Placemaking: Attracting and Retaining Today's Students

Science.gov (United States)

Knight, Brent

2016-01-01

Research suggests that the appearance of a college campus--both inside and out--is a significant criterion in college selection. As community colleges are finding it increasingly important to attract and retain students, placemaking is becoming an effective and efficient platform to support recruitment and retention. Placemaking is imagining and…

Employee Retention Strategies And Organizational Performance ...

African Journals Online (AJOL)

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

Mobile health for early retention in HIV care: a qualitative study in Kenya (WelTel Retain).

Science.gov (United States)

Smillie, Kirsten; Van Borek, Natasha; van der Kop, Mia L; Lukhwaro, Abigael; Li, Neville; Karanja, Sarah; Patel, Anik R; Ojakaa, David; Lester, Richard T

2014-01-01

Many people newly diagnosed with HIV are lost to follow-up before timely initiation of antiretroviral therapy (ART). A randomised controlled trial (RCT), WelTel Kenya1, demonstrated the effectiveness of the WelTel text messaging intervention to improve clinical outcomes among patients initiating ART. In preparation for WelTel Retain, an RCT that will evaluate the effect of the intervention to retain patients in care immediately following HIV diagnosis, we conducted an informative qualitative study with people living with HIV (n = 15) and healthcare providers (HCP) (n = 5) in October 2012. Study objectives included exploring the experiences of people living with HIV who have attempted to engage in HIV care, the use of cell phones in everyday life, and perceptions of communicating via text message with HCP. Participants were recruited through convenience sampling. Semi-structured, qualitative interviews were conducted and recorded, transcribed verbatim and analysed using NVivo software. Analysis was guided by the Theory of Reasoned Action and the Technology Acceptance Model. Results indicate that while individuals have many motivators for engaging in care after diagnosis, structural and individual barriers including poverty, depression and fear of stigma prevent them from doing so. All participants had access to a mobile phone, and most were comfortable communicating through text messages, or were willing to learn. Both people living with HIV and HCP felt that increased communication via the text messaging intervention has the potential to enable early identification of problems, leading to timely problem solving that may improve retention and engagement in care during the first year after diagnosis.

A Market-Driven Approach to Retaining Talent.

Science.gov (United States)

Cappelli, Peter

2000-01-01

Employee retention must be rethought in a free-agent market. Compensation can shape who leaves and stays. Job design and customization can tailor jobs to employee needs. Encouraging social ties among colleagues and selecting appealing locations for workplaces are other ways to retain talented workers. (SK)

Fission-product retention in HTGR fuels

International Nuclear Information System (INIS)

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

1982-01-01

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

In vitro retention force measurement for three different attachment systems for implant-retained overdenture

Directory of Open Access Journals (Sweden)

Kareem Mohammed Reda

2016-01-01

Conclusion: Regardless of the initial retention level of overdenture attachment, gradual loss of retention values is inevitable. However, the rate of retention loss in overdenture attachments is higher in types which comprised plastic parts within their components, rather than those totally made up of noble metals.

A new approach to incisor retention--the lingual spur retainer.

LENUS (Irish Health Repository)

McNamara, T G

1996-08-01

Late lower incisor crowding and incisor rotations remain a problem in orthodontics. We describe a new fixed retainer which is simple to use, allows physiological tooth movement, but prevents rotational and labio-lingual relapse.

Evaluation of retention and disposal options for tritium in fuel reprocessing

International Nuclear Information System (INIS)

Grimes, W.R.; Hampson, D.C.; Larkin, D.J.; Skolrud, J.O.; Benjamin, R.W.

1982-08-01

Five options were evaluated as means of retaining tritium released from light-water reactor or fast breeder reactor fuel during the head-end steps of a typical Purex reprocessing scheme. Cost estimates for these options were compared with a base case in which no retention of tritium within the facility was obtained. Costs were also estimated for a variety of disposal methods of the retained tritium. The disposal costs were combined with the retention costs to yield total costs (capital plus operating) for retention and disposal of tritium under the conditions envisioned. The above costs were converted to an annual basis and to a dollars per curie retained basis. This then was used to estimate the cost in dollars per man-rem saved by retaining the tritium. Only the options that used the least expensive disposal costs could approach the $1000/man-rem cost used as a guide by the Nuclear Regulatory Commission

Characterizing researchers by strategies used for retaining minority participants: results of a national survey.

Science.gov (United States)

Butler, James; Quinn, Sandra C; Fryer, Craig S; Garza, Mary A; Kim, Kevin H; Thomas, Stephen B

2013-09-01

Limited attention has been given to the optimal strategies for retaining racial and ethnic minorities within studies and during the follow-up period. High attrition limits the interpretation of results and reduces the ability to translate findings into successful interventions. This study examined the retention strategies used by researchers when retaining minorities in research studies. From May to August 2010, we conducted an online survey with researchers (principal investigators, research staff, and IRB members) and examined their use of seven commonly used retention strategies. The number and type of retention strategies used, how these strategies differ by researcher type, and other characteristics (e.g., funding) were explored. We identified three clusters of researchers: comprehensive retention strategy researchers - utilized the greatest number of retention strategies; moderate retention strategy researchers - utilized an average number of retention strategies; and limited retention strategy researchers - utilized the least number of retention strategies. The comprehensive and moderate retention strategy researchers were more likely than the limited retention strategy researchers to conduct health outcomes research, work with a community advisory board, hire minority staff, use steps at a higher rate to overcome retention barriers, develop new partnerships with the minority community, modify study materials for the minority population, and allow staff to work flexible schedules. This study is a novel effort to characterize researchers, without implying a value judgment, according to their use of specific retention strategies. It provides critical information for conducting future research to determine the effectiveness of using a combination of retention strategies. Copyright © 2013. Published by Elsevier Inc.

Retention of high-potential employees in a development finance company

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Lishani Letchmiah

2017-09-01

Full Text Available Orientation: The loss of high-potential employees was a concern to leaders at a South African development finance company. The research question that guided the study was: How can high-potential employees be retained in the company? Research purpose: The objective of the study was to identify factors that positively impact the retention of high-potential employees in a development finance company. Motivation for the study: The organisation that comprised the unit of study had prioritised employee development to retain high-potential employees, thereby aiming to build a strong talent pipeline and a sustainable knowledge base. A prevalent concern was that there were no formal retention programmes for high-potential employees. Accordingly, organisational leaders could benefit from understanding those retention factors that may serve to retain such employees. Research design, approach and method: A qualitative methodology promoted a deeper understanding of a social problem through a case study. Eleven purposefully chosen highpotential employees provided insights into factors they considered to be important in their retention. A content analysis of the data resulted in clusters of themes that addressed the research objective. Main findings: The following factors appeared to influence the retention of high-potential employees: leadership and organisational culture, organisational purpose, developmental opportunities, meaningful work and collegiality. Practical and managerial implications: Leaders in the company should consider factors that could influence the retention of high-potential employees. Such factors should be built into formal retention strategies based on the intrinsic needs of employees; the strengths that the organisational culture provides could be leveraged in this regard. Contribution: The practical value of the study was the highlighting of the factors that can be leveraged to retain high-potential employees in a development finance

Magnet retained cheek plumper in complete denture esthetics: a case report.

Directory of Open Access Journals (Sweden)

Suryakant Chhagan Deogade

2014-02-01

Full Text Available This clinical report describes a technique to improve support for sunken cheeks using magnet retained detachable acrylic cheek plumpers. The new generation of magnets with improved technology provides sufficient denture retention for clinical application. However, further follow-up may be necessary to ascertain the long-term usefulness of the magnet-retained prosthesis, because of corrosion and further loss of magnetism.

Abdominal retained surgical sponges: CT appearance

International Nuclear Information System (INIS)

Kalovidouris, A.; Kehagias, D.; Moulopoulos, L.; Gouliamos, A.; Pentea, S.; Vlahos, L.

1999-01-01

Retention of surgical sponges is rare. They cause either an aseptic reaction without significant symptoms or an exudative reaction which results in early but nonspecific symptoms. Computed tomography is very useful for recognition of retained sponges. The appearance of retained sponges is widely variable. Air trapping into a surgical sponge results in the spongiform pattern which is characteristic but unfortunately uncommon. A low-density, high-density, or complex mass is found in the majority of cases, but these patterns are not specific. Sometimes, a thin high-density capsule may be seen. Rim or internal calcification is a rare finding. Finally, a radiopaque marker is not a reliable sign. Differentiation from abscess and hematoma is sometimes difficult. (orig.)

Increasing Registered Nurse Retention Using Mentors in Critical Care Services.

Science.gov (United States)

Schroyer, Coreena C; Zellers, Rebecca; Abraham, Sam

2016-01-01

Recruiting and training 1 newly hired registered nurse can cost thousands of dollars. With a high percentage of these newly hired nurses leaving their first place of employment within their first year, the financial implications may be enormous. It is imperative that health care facilities invest in recruiting and retention programs that retain high-quality nurses. Mentorship programs in retaining and easing the transition to practice for new graduate nurses, re-entry nurses, and nurses new to a specialty area are critical in nurse retention. Discussion in this study includes the effect of implementing a mentor program into the critical care services area of a 325-bed not-for-profit community hospital in northern Indiana. Based on this study, nurses with a mentor were retained at a 25% higher rate than those not mentored. Implementation of a mentor program reduced the training cost to the facility and increased retention and morale.

Factors influencing success of cement versus screw-retained implant restorations: a clinical review

Directory of Open Access Journals (Sweden)

Ahmad Manawar

2012-10-01

Full Text Available Aim: As more and more dental practitioners are focusing on implant-supported fixed restorations, some clinicians favor the use of cement retained restorations while others consider screw retained prosthesis to be the best choice. Discussion: In screw-retained restorations, the fastening screw provides a solid joint between the restoration and the implant abutment, while in cement-retained prostheses the restorative screw is eliminated to enhance esthetics, occlusal stability, and passive fit of the restorations. The factors that influence the type of fixation of the prostheses to the implants like passivity of the framework, ease of fabrication, occlusion, esthetics, accessibility, retention and retrievability are discussed in this article with scientific studies demonstrating superior outcomes of one technique over another. Screwretained implant restorations have an advantage of predictable retention, retrievability and lack of potentially retained subgingival cement. However, a few disadvantages exist such as precise placement of the implant for optimal and esthetic location of the screw access hole and obtaining passive fit. On the other hand, cement retained restorations eliminate unesthetic screw access holes, have passive fit of castings, reduced complexity of clinical and lab procedures, enhanced esthetics, reduced cost factors and non disrupted morphology of the occlusal table. Conclusion: This article compares the advantages, potential disadvantages and limitations of screw and cement retained restorations and their specific implications in the most common clinical situation.

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

Science.gov (United States)

Catalán, Alfonso; Martínez, Alejandra; Marchesani, Francisco; González, Urcesino

2016-07-01

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

Abdominal retained surgical sponges: CT appearance

Energy Technology Data Exchange (ETDEWEB)

Kalovidouris, A.; Kehagias, D.; Moulopoulos, L.; Gouliamos, A.; Pentea, S.; Vlahos, L. [Department of Radiology, University of Athens (Greece)

1999-09-01

Retention of surgical sponges is rare. They cause either an aseptic reaction without significant symptoms or an exudative reaction which results in early but nonspecific symptoms. Computed tomography is very useful for recognition of retained sponges. The appearance of retained sponges is widely variable. Air trapping into a surgical sponge results in the spongiform pattern which is characteristic but unfortunately uncommon. A low-density, high-density, or complex mass is found in the majority of cases, but these patterns are not specific. Sometimes, a thin high-density capsule may be seen. Rim or internal calcification is a rare finding. Finally, a radiopaque marker is not a reliable sign. Differentiation from abscess and hematoma is sometimes difficult. (orig.) With 11 figs., 12 refs.

Tooth Retained Implant: No More an Oxymoron

Directory of Open Access Journals (Sweden)

Divya Bhat

2011-03-01

Full Text Available Introduction: Periodontally af-fected teeth are treated in one of the two ways. (1 Tooth retention after periodontal surgery, in which the degree of regeneration achieved is unpredictable. (2 Tooth extrac-tion and implant placement. Implants have an osseointegrated surface which does not provide adequate shock absorption. Regeneration can be achieved by resecting the crown of the affected tooth and submerging the root. This technique has not had a clinical application so far as the tooth becomes difficult to restore. Placing an implant within the root can make the retained root restorable. At the same time, as the implant is placed within the root surface it achieves a periodontal integration which dampens occlusal forces better than osseointegration. Therefore, such a “tooth retained implant” may serve as an additional treatment option with significant benefits over tooth retention and implant placement alone. The hypothesis: Implants placed within retained roots have shown cementum deposition and attachment of periodontal ligament fibers over their surface. This periodontal attachment may be able to dam-pen forces better than in an osseointegrated implant. Moreover, since an implant is being placed, the crown of the tooth can be resected and submerged. This prevents epithelial migration, allows for the periodontal ligament cells to populate the wound and favors regeneration.Evaluation of the hypothesis: The technique of placing implants within cavities prepared in the root and then submerging them are simple for any practitioner placing implants routinely.

Esthetic, functional, and prosthetic outcomes with implant-retained finger prostheses.

Science.gov (United States)

Aydin, Cemal; Nemli, Secil Karakoca; Yilmaz, Handan

2013-04-01

Traumatic amputation of fingers results in a serious impairment of hand function and affects the psychological status of the patients. The implant-retained finger prostheses are an alternative treatment. The aim of this case report is to represent the use of osseointegrated implants for retention of finger prostheses in a patient with amputated thumb and index finger. Dental implants were placed in the residual bone of the fingers using two-stage surgery. Custom-made attachments were used to provide retention between implants and silicone prostheses. Prosthetic fingernails were made of composite resin material. After 6 months, implants were clinically successful, and the patient was satisfied with the appearance and the function of the prostheses. The complications of broken prosthetic nail and mild discoloration were observed. Reconstruction of amputated fingers with implant-retained prosthesis is a worthwhile treatment providing esthetic, functional, and psychological benefits, although some complications might be experienced. Clinical relevance Implant-retained finger prostheses are an acceptable treatment modality for patients with amputated fingers. Evaluating implant prognosis, functional results and prosthetic results of the patients are necessary to address the benefits and complications of the treatment.

13 CFR 120.861 - Job creation or retention.

Science.gov (United States)

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 specified...

Nuclear reactor melt-retention structure to mitigate direct containment heating

Science.gov (United States)

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

1991-01-01

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

Novel word retention in bilingual and monolingual speakers

Directory of Open Access Journals (Sweden)

Pui Fong eKan

2014-09-01

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

Novel word retention in bilingual and monolingual speakers.

Science.gov (United States)

Kan, Pui Fong; Sadagopan, Neeraja

2014-01-01

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

Retaining the mental health nursing workforce: early indicators of retention and attrition.

Science.gov (United States)

Robinson, Sarah; Murrells, Trevor; Smith, Elizabeth M

2005-12-01

In the UK, strategies to improve retention of the mental health workforce feature prominently in health policy. This paper reports on a longitudinal national study into the careers of mental health nurses in the UK. The findings reveal little attrition during the first 6 months after qualification. Investigation of career experiences showed that the main sources of job satisfaction were caregiving opportunities and supportive working relationships. The main sources of dissatisfaction were pay in relation to responsibility, paperwork, continuing education opportunities, and career guidance. Participants were asked whether they predicted being in nursing in the future. Gender and ethnicity were related to likelihood to remain in nursing in 5 years time. Age, having children, educational background, ethnic background, and time in first job were associated with likelihood of remaining in nursing at 10 years. Associations between elements of job satisfaction (quality of clinical supervision, ratio of qualified to unqualified staff, support from immediate line manager, and paperwork) and anticipated retention are complex and there are likely to be interaction effects because of the complexity of the issues. Sustaining positive experiences, remedying sources of dissatisfaction, and supporting diplomats from all backgrounds should be central to the development of retention strategies.

Interventions that promote retention of experienced registered nurses in health care settings: a systematic review.

Science.gov (United States)

Lartey, Sarah; Cummings, Greta; Profetto-McGrath, Joanne

2014-11-01

The aim of this review was to report the effectiveness of strategies for retaining experienced Registered Nurses. Nursing researchers have noted that the projected nursing shortage, if not rectified, is expected to affect healthcare cost, job satisfaction and quality patient care. Retaining experienced nurses would help to mitigate the shortage, facilitate the transfer of knowledge and provision of quality care to patients. A systematic review of studies on interventions that promote the retention of experienced Registered Nurses in health care settings. Twelve studies were included in the final analysis. Most studies reported improved retention as a result of the intervention. Team work and individually targeted strategies including mentoring, leadership interest and in-depth orientation increased job satisfaction and produced higher retention results. Few published studies have examined interventions that promote the retention of experienced Registered Nurses in healthcare. Retention was highest when multiple interventions were used. Further research is needed to inform nurse leaders of ways to retain nurses and to maintain quality care in health care settings. Programmes targeting the retention of experienced nurses need to be considered when implementing measures to decrease the nursing shortage and its effects on quality care. © 2013 John Wiley & Sons Ltd.

Salary is not enough to attract and retain the best

Directory of Open Access Journals (Sweden)

Rosa María Fuchs Ángeles

2015-09-01

Full Text Available Organizations face the challenge of attracting and retaining talented staff. In some instances, a reference to the existence of a war for talent is made. It is that way that the retention of workers has stopped being managed, exclusively, with the offer of good salaries. This paper explores, in a first instance, the theoretical framework that describes the principal tools of talent retention that companies develop, and that are considered as part of the total remuneration that workers receive: economic compensations, recognition, career plans and staff development, feedback, personal and professional life balance, social network and team making, proper relationship with superiors and organizational climate life. Later, the results that were obtained from interviews with ten of the best companies to work for in Peru, according to the Great Place to Work Institute ranking in 2007, on retaining talent tools that they implement are shown. Finally, conclusions on the case studies are presented.

Retention and Stability of Implant-Retained Mandibular Overdentures Using Different Types of Resilient Attachments: An In Vitro Study.

Science.gov (United States)

ELsyad, Moustafa Abdou; Agha, Nora Nory; Habib, Ahmed Ali

2016-01-01

The aim of this study was to evaluate and compare the retention and stability of mandibular implant overdentures using different types of resilient attachments. Two implant analogs were inserted in the canine areas of an acrylic edentulous mandibular model. A metal-reinforced experimental overdenture was constructed and connected to the implant analogs (on two occasions) using either resilient telescopic or Locator attachments. Locators were divided into three subgroups according to the degree of retention of the male nylon insert: Locator extra-light retention (blue insert), Locator light retention (pink insert), and Locator medium retention (transparent insert). Vertical and oblique (anterior, posterior, and lateral) dislodging forces were measured at the beginning of the study (initial retention) and after 540 cycles of denture insertion and removal (final retention). For all dislodging forces, Locator medium recorded the highest initial and final retention. Telescopic attachments recorded the lowest retention during vertical and anterior dislodging, and Locator extra-light recorded the lowest retention during lateral and posterior dislodging. For all types of Locator attachments, anterior dislodging recorded the highest initial and final retention, and lateral dislodging recorded the lowest retention. For the telescopic attachment, posterior dislodgment recorded the highest initial and final retention, and anterior dislodging recorded the lowest retention. After repeated denture insertions and removals, the highest retention and stability were recorded with Locator medium followed by Locator light. The lowest retention was recorded with resilient telescopic attachment, and the lowest stability was recorded with Locator extra-light.

Retention of Hydrogen Isotopes in Divertor Tiles Used in JT-60U

International Nuclear Information System (INIS)

Hirohata, Y.; Shibahara, T.; Tanabe, T.; Oya, Y.; Arai, T.; Gotoh, Y.; Masaki, K.; Yagyu, J.; Oyaidzu, M.; Okuno, K.; Nishikawa, M.; Miya, N.

2005-01-01

Retention characteristics of deuterium and hydrogen retained in graphite tiles placed in the divertor region of JT-60U were investigated by thermal desorption spectroscopy (TDS). The deuterium retained in the near surface of all graphite tiles was mostly replaced by hydrogen due to exposure to hydrogen plasma at the final stage operations, resulting in main deuterium retention in the deeper region. The dominant species desorbed from the divertor tiles were H 2 , HD, D 2 and CH 4 . The smallest retention of hydrogen isotopes (H+D) was observed in the outer divertor tile which was eroded with maximum of 20 μm depth. The amount of H+D retained in the inner divertor tiles covered by the re-deposited layers increased with the thickness of the re-deposited layers. Hydrogen isotopes concentration ((H+D)/C) in the re-deposited layers was ∼0.02, which was much smaller than those observed in JET and other devices

The role of psychological ownership in retaining talent: A systematic literature review

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Chantal Olckers

2012-02-01

Full Text Available Orientation: Managing psychological ownership can have positive attitudinal and behavioural effects, promote organisational effectiveness and support talent retention.Research purpose: This paper seeks to explore and describe psychological ownership, distinguish it from other work-related attitudes and clarify the role that psychological ownership can play in retaining talent.Motivation for the study: Previous studies of human resource practices and organisational characteristics that affect organisational commitment and the retention of talent have reported that absent variables could be responsible for varied results. Psychological ownership could be one of them.Research design, approach and method: Based on a systematic review of the literature published over the last 20 years, the authors synthesised various research perspectives into a framework of psychological ownership and its links to retaining talent.Main findings: The authors found that psychological ownership was a comprehensive multidimensional construct. It is distinct from other work-related attitudes and seems capable of enabling organisations to retain the talents of skilled employees.Practical/managerial implications: Organisations can benefit from psychological ownership because it leads employees to feel responsible towards targets (like organisations and to show stewardship. It can help organisations to retain talent and influence the intentions of skilled employees to remain with their organisations.Contribution/value-add: Psychological ownership, as an integrated multidimensional construct, has expanded the existing theory about the organisational commitment and work-related attitudes that organisations need to retain talent in the 21st century.

Effects of temperature and surface contamination on D retention in ultrathin Li films on TZM

Energy Technology Data Exchange (ETDEWEB)

Capece, A.M., E-mail: acapece@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Roszell, J.P. [Princeton University, Department of Chemical and Biological Engineering, Princeton, NJ (United States); Skinner, C.H. [Princeton Plasma Physics Laboratory, Princeton, NJ (United States); Koel, B.E. [Princeton University, Department of Chemical and Biological Engineering, Princeton, NJ (United States)

2015-08-15

In this work, we investigate deuterium retention at the Mo–Li interface by studying thin Li films three monolayers thick on a TZM Mo alloy. Li films at temperatures between 315 and 460 K were exposed to a deuterium ion beam and D retention was measured using temperature programmed desorption. In the absence of oxygen, D is retained as LiD, and the relative amount of retained D decreases with increasing substrate temperature. In three-monolayer thick lithium oxide films, the amount of D retained was 2.5 times higher than the amount retained as LiD in the metallic Li film. However, oxygen reduces the thermal stability of D in the film, causing D{sub 2}O and D{sub 2} to be released from the surface at temperatures 150–200 K below the LiD decomposition temperature. These results highlight the importance of maintaining a metallic Li layer for high D retention in Li films on TZM at elevated temperatures.

Recruitment and retention of women in fishing communities in HIV ...

African Journals Online (AJOL)

... complete all study visits. Conclusion: Women had better retention rates than men at 18 months. Strategies for recruiting and retaining younger women and those who have stayed for less than 5 years need to be developed for improved retention of women in fishing communities in HIV prevention and research Programs.

Implant-Retained Auricular Prosthesis: A Case Report

OpenAIRE

Ozturk, A. Nilgun; Usumez, Aslihan; Tosun, Zekeriya

2010-01-01

Extraoral implant retained prosthesis have been proven to be a predictable treatment option for maxillofacial rehabilitation. This case report describes the clinical and laboratory procedures for fabricating an auricular prosthesis. In this case report, an auricular prosthesis was fabricated for a patient who lost the left and right external ear in an electrical burn. Extraoral implants and bar-and-clip retention for the proper connection of the auricular prosthesis to implant were used. This...

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

Science.gov (United States)

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.…

DETERMINANTS OF RETAINED EARNINGS IN PROFITABLE STEEL COMPANIES IN INDIA: A STUDY OF STEEL SECTOR

OpenAIRE

Dr. Sohaib Masood

2018-01-01

In this paper an attempt has been made to identify the important determinants of retained earnings in profitable steel companies in steel sector of India and which have impact on the retention of earnings of steel companies under study. Multiple linear regression is used to identify the determinants of retained earnings for a period of sixteen years. Also the importance of retained earnings as a source of finance for steel sector companies is also studied in the paper.

Tritium retention properties of tungsten, graphite and co-deposited carbon film

International Nuclear Information System (INIS)

Nobuta, Y.; Hatano, Y.; Matsuyama, M.; Abe, S.; Akamaru, S.; Yamauchi, Y.; Hino, T.; Suzuki, S.; Akiba, M.

2014-01-01

DT + ion irradiation was performed on polycrystalline tungsten, graphite and carbon film and both the amount of retained tritium and the reduction of retained tritium after preservation in vacuum were investigated using an IP technique and BIXS. In addition, the relationship between the retention properties of tritium and the microstructure of graphite and carbon film were studied with Raman spectroscopy. The amount of retained tritium in tungsten was smaller than in both graphite and carbon film. After 1 keV of DT + irradiation, graphite showed no reduction of the amount of retained tritium after six months preservation while that of carbon film decreased by approximately 20% after 40 days preservation. It was suggested that this difference might be associated with differences in the microstructure between graphite and carbon film. In tungsten, the amount of retained tritium decreased to approximately half after 18 days preservation. As the incident energy of implanted tritium to tungsten increased, the decrease in tritium retention during preservation became slower. Tungsten's properties of releasing tritium while preserved in vacuum would be a useful tool for the reduction/removal of retained tritium

Employee retention within the Information Technology Division of a South African Bank

Directory of Open Access Journals (Sweden)

Joy Mohlala

2012-05-01

Research purpose: To understand the challenges faced by the bank’s information technology leadership team to retain employees. Motivation for the study: To understand the challenges faced in attracting and retaining information technology professionals, and how this can serve as input for reducing skills shortages in Information Technology Divisions. Research design, approach and method: An interpretive approach employing a case study strategy and qualitative methods was employed. Semi structured interviews were conducted with thirteen senior managers and four directors of the bank’s Information Technology Division, who were selected on a purposive basis. Data were subjected to Creswell’s four stage data analysis process. Main findings: Findings indicate that employee turnover is the main contributor of skills shortages within the studied division. The lack of a retention strategy is making it difficult for leadership to identify crucial skills that must be retained. Practical/managerial implications: Evidence suggests that this bank, although they would like to retain information technology professionals, is not creating an environment conducive to do this, as little attention is paid to the unique demands of this group of employees. Contribution/value-add: This study investigates a specific group of employees for which a unique retention strategy does not exist. In understanding the challenges that impact on attracting and retaining information technology professionals, this study can contribute to the development of a retention strategy for these employees.

Do we really understand how to retain nurses?

Science.gov (United States)

O'Brien-Pallas, Linda; Duffield, Christine; Hayes, Laureen

2006-05-01

To compare views of nurse executives with those of nurses who have left the profession on the importance of retention strategies. Although much has been written about nursing turnover, there continues to be dissonance among decision makers as to why nurses leave the profession and what the most crucial issues are for retention. Factor analysis was undertaken to compare responses of nurse executives with those of nurses employed outside of nursing. Contract requirements represented the greatest discrepancy, 1.07, followed by legal and employer issues, 1.02; worklife/homelife balance, 0.91; external values and beliefs about nursing, 0.75; and professional practice, 0.29. A disparity exists between perceptions of nurse executives and those of nurses who have left the profession as to which issues are most critical in retention. We suggest that nurse executives ensure sufficient organizational support for nursing unit managers who are more likely to understand methods of retaining nurses at the clinical interface.

The Wages of Failure: New Evidence on School Retention and Long-Run Outcomes

Science.gov (United States)

Babcock, Philip; Bedard, Kelly

2011-01-01

By estimating differences in long-run education and labor market outcomes for cohorts of students exposed to differing state-level primary school retention rates, this article estimates the effects of retention on all students in a cohort, retained and promoted. We find that a 1 standard deviation increase in early grade retention is associated…

31 CFR 103.38 - Nature of records and retention period.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Nature of records and retention... § 103.38 Nature of records and retention period. (a) Wherever it is required that there be retained... reasonable period of time, taking into consideration the nature of the record, and the amount of time expired...

Effect of Retention in Elementary Grades on Grade 9 Motivation for Educational Attainment

Science.gov (United States)

Cham, Heining; Hughes, Jan N.; West, Stephen G.; Im, Myung Hee

2014-01-01

This study investigated the effect of grade retention in elementary school on students’ motivation for educational attainment in grade 9. We equated retained and promoted students on 67 covariates assessed in grade 1 through propensity score weighting. Retained students (31.55%, nretained = 177) and continuously promoted students (68.45%, npromoted = 384) were compared on the bifactor model of motivation for educational attainment (Cham, Hughes, West, & Im, 2014). This model consists of a General factor (student’s overall motivation for educational attainment), and three specific factors: student perceived Teacher Educational Expectations, Peer Educational Aspirations, and Value of Education. Measurement invariance between retained and promoted groups was established. Retained students scored significantly higher than promoted students on each specific factor but not on the General factor. Results showed that the retained and promoted students did not significantly differ on the General factor. The retained students had significantly higher scores on each specific factor than the promoted students. The results suggested that grade retention may not have the negative effects so widely assumed in the published literature; it is an expensive intervention with minimal evidence of benefits to the retained student. PMID:25636258

60Co retention by Mexican montmorillonites

International Nuclear Information System (INIS)

Pacheco, G.; Martinez, V.; Bosch, P.; Bulbulian, S.

1995-01-01

Radioactive elements may be retained by clays. The ability of natural Mexican clays to retain radioactive Co from aqueous solutions, is discussed. Experiments were performed with solutions containing labeled cobalt. The effect of contact time on Co 2+ retention was studied. It was found that the Co 2+ uptake value in dehydrated montmorillonites is between 0.30 and 0.70 meq g -1 of clay. A sorption sequence was obtained for the various clays. The samples were characterized, before and after cobalt exchange, by X-ray diffraction. (author). 7 refs., 3 figs., 3 tabs

Customer retention: A theoretical perspective of service failure and service recovery in the hotel industry

OpenAIRE

D. J. Petzer; T. F.J. Steyn

2006-01-01

Purpose: The purpose of this paper is to provide a theoretical perspective on customer retention activities associated with service failure management and service recovery as a means to retain customers in the hotel industry - and to improve the competitiveness of a hotel. The research is pursued with the following objectives in mind: To determine the customer retention activities involved in the service failure management needed by hotels to retain customers. To determine the customer ...

Magnet-retained implant-supported overdentures: review and 1-year clinical report.

Science.gov (United States)

Ceruti, Paola; Bryant, S Ross; Lee, Jun-Ho; MacEntee, Michael I

2010-01-01

Open-field aluminum-nickle-cobalt magnets have been used in prosthodontics for many years, but success has been limited because these magnets are susceptible to corrosion by the saliva and because their retentive force is weak relative to the initial retention offered by mechanical attachments. More recently, magnets have been made from alloys of the rare earth elements samarium and neodymium, which provide stronger magnetic force per unit size. In addition, a new generation of laser-welded containers has improved protection from salivary corrosion. The current resurgence of interest in this type of attachment appears justified because, unlike mechanical attachments, magnets have potential for unlimited durability and might therefore be superior to mechanical ball or bar attachments for the retention of removable prostheses on implants. To date, no long-term prospective trials have been conducted to confirm the clinical durability of this new generation of magnets for retaining dentures on either teeth or implants. The aim of this study was to document initial clinical experiences and levels of satisfaction among edentulous patients treated with mandibular implant-supported overdentures retained using a new generation of rare-earth magnetic attachments. At the outset, all but one of the 17 patients had had several years of experience with implant-supported overdentures. During the first year, the mean overall satisfaction among these 17 patients increased from less than 70 to over 90 out of 100 (standardized visual analogue scale). No unusual difficulties were encountered in rendering the treatment or maintaining the attachments. This report offers preliminary evidence of the excellent potential of these magnets for retaining mandibular implant-supported overdentures.

Mentoring: the retention factor in the acute care setting.

Science.gov (United States)

Funderburk, Amy E

2008-01-01

The most difficult time to retain staff nurses can be the first year after hire. Because of the high costs of recruitment and orientation, retention of these new employees is essential. Mentoring is a viable retention tool for the new employee and for existing experienced nurses. Mentoring also provides professional growth benefits that appeal to existing employees and increase their job enjoyment and satisfaction.

A descriptive and factor analytical study of salient retention ...

African Journals Online (AJOL)

Targeting, acquiring and retaining the right customers are at the core of many ... Future research on a comprehensive examination of satisfaction, loyalty, ... relationship marketing, customer retention, customer defection, complaints handling.

Effective Retention Strategies for Diverse Employees.

Science.gov (United States)

Musser, Linda R.

2001-01-01

Discusses methods to determine why employees leave or stay, based on experiences at Pennsylvania State University libraries. Considers retention tools that work best to retain diverse employees, including mentoring, networking, career and learning opportunities, balance between work and home life, a welcoming climate, and support for research.…

Foliar retention, transport and leaching of polonium-210 and lead-210

Energy Technology Data Exchange (ETDEWEB)

Athalye, V V; Mistry, K B

1972-01-01

Polonium-210 and lead-210, the long-lived daughter radionuclides of gaseous radon-222, are deposited on plant surfaces under conditions of atmospheric washout. Foliar retention, transport and leaching of these radionuclides in Red Kidney beans were investigated in nutrient culture experiments. Under identical conditions, over 90 percent of foliar applied radiolead was retained by the plant while only about 30 percent of polonium was retained. Over a 48-hr period small quantities of polonium were translocated from the treated leaflet to other parts of the plant. By comparison, radiolead was totally immobilized at the site of retention. Leachability of root absorbed radiolead from bean leaves was 20-fold greater than that of polonium. The marked differences in the extent of foliar retention, translocation and leaching of polonium and radiolead could significantly affect the levels of these long-lived radionuclides attained in plants.

Factors Influencing Neurosurgeons’ Decision to Retain in a Work Location: A Qualitative Study

Science.gov (United States)

Rafiei, Sima; Arab, Mohammad; Rashidian, Arash; Mahmoudi, Mahmood; Rahimi-Movaghar, Vafa

2015-01-01

Introduction: Physician retention is a serious concern to have an effective and efficient health system; the key challenge is how best to encourage and retain health providers in their work location. There have been considerable studies on factors influencing physicians’ retention but little research has been conducted in Iran. This study aims to determine the affecting factors from neurosurgeons’ viewpoint to support policy makers in proposing a sort of evidence based retention strategies. Methods: We conducted semi structured interviews with 17 neurosurgeons working in 9 provinces of Iran between September and November 2014. We included physicians remaining to work in a particular community for at least 3 years and asked them about the factors influenced their decision to retain in a work place. Data were thematically analyzed using “framework approach” for qualitative research. Results: Satisfaction with monetary incentives, availability of adequate clinical infrastructure in a community and appropriate working condition were most commonly cited factors mentioned by all participants as key reasons for retention. Furthermore elements which contributed to the quality of living condition, personal background and incentives, family convenience were emphasized by majority of them. A small number of participants mentioned opportunity for continuing learning and updating knowledge as well as supportive organizational policies as important motivators in a workplace. Conclusion: Ministry of Health and Medical Education (MOHME) should consider a multifaceted and holistic approach to improve neurosurgeons’ retention in their work location. Our findings suggests a combination of financial remuneration, establishment of adequate hospitals and clinical facilities, collaborative working environment with reasonable workload, proper living condition, family support and facilities for professional development to be employed as an effective strategy for promoting

Rehabilitation of maxillary arch with attachment-retained mesh-reinforced single complete denture

Science.gov (United States)

Vamsi Krishna, C H; Rao, A Kaleshwar; Sekhar, N Chandra; Shastry, Y Mahadev

2014-01-01

Fabrication of conventional complete dentures was one of the most commonly advised treatment options to mange edentulous patients since many years. One of the commonly encountered challenging tasks in prosthodontics is a clinical situation in which patients have maxillary completely edentulous arches opposing mandibular natural dentition. This situation can be effectively managed by retaining some of the natural teeth as overdenture abutments. Tooth supported overdenture retained by attachments will improve retention, support and stability, and reduces rate of ridge resorption along with psychological benefits to the patients by providing tactile sensation. The present case report describes management of patients with edentulous maxillary arch opposing natural mandibular dentition-rehabilitated attachment-retained mesh-reinforced overdenture. PMID:24574522

Rehabilitation of maxillary arch with attachment-retained mesh-reinforced single complete denture.

Science.gov (United States)

Vamsi Krishna, C H; Rao, A Kaleshwar; Sekhar, N Chandra; Shastry, Y Mahadev

2014-02-26

Fabrication of conventional complete dentures was one of the most commonly advised treatment options to mange edentulous patients since many years. One of the commonly encountered challenging tasks in prosthodontics is a clinical situation in which patients have maxillary completely edentulous arches opposing mandibular natural dentition. This situation can be effectively managed by retaining some of the natural teeth as overdenture abutments. Tooth supported overdenture retained by attachments will improve retention, support and stability, and reduces rate of ridge resorption along with psychological benefits to the patients by providing tactile sensation. The present case report describes management of patients with edentulous maxillary arch opposing natural mandibular dentition-rehabilitated attachment-retained mesh-reinforced overdenture.

Simplifying ART cohort monitoring: Can pharmacy stocks provide accurate estimates of patients retained on antiretroviral therapy in Malawi?

Directory of Open Access Journals (Sweden)

Tweya Hannock

2012-07-01

Full Text Available Abstract Background Routine monitoring of patients on antiretroviral therapy (ART is crucial for measuring program success and accurate drug forecasting. However, compiling data from patient registers to measure retention in ART is labour-intensive. To address this challenge, we conducted a pilot study in Malawi to assess whether patient ART retention could be determined using pharmacy records as compared to estimates of retention based on standardized paper- or electronic based cohort reports. Methods Twelve ART facilities were included in the study: six used paper-based registers and six used electronic data systems. One ART facility implemented an electronic data system in quarter three and was included as a paper-based system facility in quarter two only. Routine patient retention cohort reports, paper or electronic, were collected from facilities for both quarter two [April–June] and quarter three [July–September], 2010. Pharmacy stock data were also collected from the 12 ART facilities over the same period. Numbers of ART continuation bottles recorded on pharmacy stock cards at the beginning and end of each quarter were documented. These pharmacy data were used to calculate the total bottles dispensed to patients in each quarter with intent to estimate the number of patients retained on ART. Information for time required to determine ART retention was gathered through interviews with clinicians tasked with compiling the data. Results Among ART clinics with paper-based systems, three of six facilities in quarter two and four of five facilities in quarter three had similar numbers of patients retained on ART comparing cohort reports to pharmacy stock records. In ART clinics with electronic systems, five of six facilities in quarter two and five of seven facilities in quarter three had similar numbers of patients retained on ART when comparing retention numbers from electronically generated cohort reports to pharmacy stock records. Among

Recruitment and Retention with a Spin

Science.gov (United States)

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…

Retention factors in relation to organisational commitment in medical and information technology services

Directory of Open Access Journals (Sweden)

Jeannette van Dyk

2012-02-01

Full Text Available Orientation: Retaining staff with scarce and critical skills in the medical and information technology (IT industry has become a top priority because of skills shortages.Research purpose: The objectives of the study were to investigate empirically: (1 the relationship between employees’ satisfaction with organisational retention factors (measured by the Retention Factors Scale and their organisational commitment (measured by the Organisational Commitment Questionnaire and (2 whether gender, age, race and tenure groups differ significantly in terms of these variables.Motivation for the study: Medical and information technology professionals have specialised and hard to replace skills. They also have strong tendencies to leave their organisations and countries. Understanding the retention factors that will increase their organisational commitment may benefit the organisations who want to retain their valuable talent.Research design, approach and method: The researchers used a cross-sectional survey design to collect data from a purposive sample of 206 staff members who had scarce skills in a South African medical and information technology services company. Correlational and inferential statistics were computed to achieve the objectives.Main findings: The results showed that the participants’ satisfaction with retention factors has a significant relationship with their organisational commitment and that the biographical groups differ significantly in terms of the variables.Practical/managerial implications: The measured retention factors were all associated with human resource management practices that influence employees’ intentions to leave.Contribution/value-add: The results are important to managers who are interested in retaining staff who have scarce skills and provide valuable pointers for designing effective retention strategies.

Does the amount of trees retained at clearfelling of temperate and boreal forests influence biodiversity response?

Directory of Open Access Journals (Sweden)

Fedrowitz Katja

2012-05-01

Full Text Available Abstract Clear-felling is one of the main methods used in many parts of the world for the production of pulp, timber and bioenergy, leading to a simplified forest structure and species composition. One of the measures to mitigate the impact of logging on biodiversity is the retention of trees at final harvest. Tree retention approaches in forestry are still rather new, although widely distributed across different continents. Several studies have been performed on the effects of retention trees on biodiversity but to date there is no evidence on the relation between the amounts of trees, i.e. the number, volume or area per ha retained, and the response of biodiversity. The overall aim of our review will be to provide forest practitioners and conservationists in temperate and boreal forests with more detailed recommendations regarding the amount of trees that should be retained in order to achieve positive effects for biodiversity compared to traditional clear-cutting.

Effect of retention in elementary grades on grade 9 motivation for educational attainment.

Science.gov (United States)

Cham, Heining; Hughes, Jan N; West, Stephen G; Im, Myung Hee

2015-02-01

This study investigated the effect of grade retention in elementary school on students' motivation for educational attainment in grade 9. We equated retained and promoted students on 67 covariates assessed in grade 1 through propensity score weighting. Retained students (31.55%, nretained=177) and continuously promoted students (68.45%, npromoted=384) were compared on the bifactor model of motivation for educational attainment (Cham, Hughes, West & Im, 2014). This model consists of a General factor (student's overall motivation for educational attainment), and three specific factors: student perceived Teacher Educational Expectations, Peer Educational Aspirations, and Value of Education. Measurement invariance between retained and promoted groups was established. Retained students scored significantly higher than promoted students on each specific factor but not on the General factor. Results showed that the retained and promoted students did not significantly differ on the General factor. The retained students had significantly higher scores on each specific factor than those of the promoted students. The results suggested that grade retention may not have the negative effects so widely assumed in the published literature; it is an expensive intervention with minimal evidence of benefits to the retained student. Copyright © 2014 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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

2012-12-01

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

Retaining Aspiring Scholars (retention, Students of Color)

Science.gov (United States)

Walters, Nancy Bannister

Tinto's retention model provided the theoretical framework for this research study of the academic and social integration of academically talented students of color into the graduate and professional science degree pipeline. The site for this study was the Life Sciences Summer Undergraduate Research Program of the University of Minnesota. This program recruits academically talented undergraduates from throughout the nation for participation in two months of research, academic study and orientation to science graduate and professional programs. The quantitative data source consisted of survey responses by 108 alumni of the Summer Undergraduate Research Program to the Institutional Integration Scale developed by Ernest Pascarella and Patrick Terenzini. The scale measures academic integration, social integration and institutional and goal commitment of students. The qualitative data source consisted of one-on-one interviews of 14 summer program alumni of Caucasian, Latino and African American background. The quantitative results were not significant, while the qualitative results demonstrated the importance to alumni interviewed of the challenging academic research work, personally confirming peer group socialization, and supportive student faculty interactions. The study showed the importance of programs like these for helping students of color plan upper level college study and graduate/professional school enrollment. Program characteristics that influenced decision making regarding school and career choices by study participants and specifically by students of color were involvement of faculty in recruiting and mentoring students; socialization to the graduate student role through peer group relations and student maturation and empowerment through participation in a high level academic program. Study findings indicated that supportive and empowering faculty contact was considered most important by students of color who continued on to graduate and professional

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

Science.gov (United States)

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. © 2015 American Association for Marriage and Family Therapy.

Assessment of nurse retention challenges and strategies in Lebanese hospitals: the perspective of nursing directors.

Science.gov (United States)

El-Jardali, Fadi; Merhi, Mirvat; Jamal, Diana; Dumit, Nuhad; Mouro, Gladys

2009-05-01

Assess nurse retention challenges and strategies as perceived by nursing directors in Lebanese hospitals. The Kampala Health Workforce Declaration stressed the importance of retaining an effective, responsive and equitably distributed health workforce, particularly nurses. Little is known about nurse retention challenges and strategies in Lebanon. Nursing directors of 76 hospitals participated and were sent a two-page survey on perceived retention challenges and hospital-based retention strategies. Retention challenges included unsatisfactory salary, unsuitable shifts and working hours, as well as better opportunities in other areas within or outside Lebanon. Retention strategies included implementing financial rewards and benefits, a salary scale, staff development, praise and improving work environment. Nursing directors did not address all perceived challenges in their strategies. To better manage the nursing workforce, nursing directors should regularly measure and monitor nurse turnover rates and also their causes and predictors. Nursing directors should develop, implement and evaluate retention strategies. More information is needed on the management and leadership capacities of nursing directors in addition to their span of control. Nursing directors are facing challenges in retaining their nurses. If these problems are not addressed, Lebanon will continue to lose competent and skilled nurses.

Employee Retention: A Challenge of the Nineties.

Science.gov (United States)

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…

A conservative method of retaining an interim obturator for a total maxillectomy patient

Directory of Open Access Journals (Sweden)

Nirmal Famila Bettie

2017-01-01

Full Text Available Interim obturators are indicated during the postsurgical phases. It promotes surgical healing and serves as a temporary prosthesis to rehabilitate a patient with intra-oral surgical defect. Retention is gained by wiring, surgical suturing, and other noninvasive methods to enable functional rehabilitation and easy replacement with a permanent obturator. Interim obturators serve as an easy guide for replacing with definitive obturators by indicating prosthesis extensions and the required method of retention. A more conservative and noninvasive method of retaining an interim obturator for a maxillectomy patient is described in this case report.

A Conservative Method of Retaining an Interim Obturator for a Total Maxillectomy Patient.

Science.gov (United States)

Bettie, Nirmal Famila

2017-11-01

Interim obturators are indicated during the postsurgical phases. It promotes surgical healing and serves as a temporary prosthesis to rehabilitate a patient with intra-oral surgical defect. Retention is gained by wiring, surgical suturing, and other noninvasive methods to enable functional rehabilitation and easy replacement with a permanent obturator. Interim obturators serve as an easy guide for replacing with definitive obturators by indicating prosthesis extensions and the required method of retention. A more conservative and noninvasive method of retaining an interim obturator for a maxillectomy patient is described in this case report.

Nursing practice environment: a strategy for mental health nurse retention?

Science.gov (United States)

Redknap, Robina; Twigg, Di; Rock, Daniel; Towell, Amanda

2015-06-01

Historically, mental health services have faced challenges in their ability to attract and retain a competent nursing workforce in the context of an overall nursing shortage. The current economic downturn has provided some respite; however, this is likely to be a temporary reprieve, with significant nursing shortages predicted for the future. Mental health services need to develop strategies to become more competitive if they are to attract and retain skilled nurses and avoid future shortages. Research demonstrates that creating and maintaining a positive nursing practice environment is one such strategy and an important area to consider when addressing nurse retention. This paper examines the impact the nursing practice environment has on nurse retention within the general and mental health settings. Findings indicate, that while there is a wealth of evidence to support the importance of a positive practice environment on nurse retention in the broader health system, there is little evidence specific to mental health. Further research of the mental health practice environment is required. © 2015 Australian College of Mental Health Nurses Inc.

The Irreplaceables: Understanding the Real Retention Crisis in America's Urban Schools. Executive Summary

Science.gov (United States)

TNTP, 2012

2012-01-01

Discussions of teacher turnover usually focus on "how many" teachers leave schools each year, without regard for their performance in the classroom. This oversimplification masks the real teacher retention crisis: not only a failure to retain enough teachers, but a failure to retain the "right" teachers. This executive summary presents findings of…

Plastic debris retention and exportation by a mangrove forest patch

International Nuclear Information System (INIS)

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

2014-01-01

Highlights: • Estuaries and mangrove forests are rarely studied for marine plastic debris loads. • Types of plastic items and mangrove forest habitats determine the potential of debris retention. • Mangrove habitats are temporary sinks of plastic debris from river and marine origins. • Plastics rapidly accumulate in mangrove forest, but are exported slowly. • Fauna and fishers using mangrove forest habitats are at risk of interaction with plastic debris. -- Abstract: 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)

Receipt of special education services following elementary school grade retention.

Science.gov (United States)

Silverstein, Michael; Guppy, Nicole; Young, Robin; Augustyn, Marilyn

2009-06-01

To estimate the proportion of children who receive an Individualized Education Program (IEP) following grade retention in elementary school. Longitudinal cohort study. Children retained in kindergarten or first (K/1) grade and third grade, presumably for academic reasons, were followed up through fifth grade. Presence or absence of an IEP. A total of 300 children retained in K/1 and 80 retained in third grade were included in the study. Of the K/1 retainees, 68.9% never received an IEP during the subsequent 4 to 5 years; of the third-grade retainees, 72.3% never received an IEP. Kindergarten/first-grade retainees in the highest quintile for socioeconomic status and those with suburban residence were less likely to receive an IEP than retained children in all other socioeconomic status quintiles (adjusted odds ratio, 0.17; 95% confidence interval, 0.05-0.62) and in rural communities (0.16; 0.06-0.44). Among K/1 retainees with persistently low academic achievement in math and reading, as assessed by standardized testing, 38.2% and 29.7%, respectively, never received an IEP. Most children retained in K/1 or third grade for academic reasons, including many of those who demonstrated sustained academic difficulties, never received an IEP during elementary school. Further studies are important to elucidate whether retained elementary schoolchildren are being denied their rights to special education services. In the meantime, early-grade retention may provide an opportunity for pediatricians to help families advocate for appropriate special education evaluations for children experiencing school difficulties.

Modeling Coast Redwood Variable Retention Management Regimes

Science.gov (United States)

John-Pascal Berrill; Kevin O' Hara

2007-01-01

Variable retention is a flexible silvicultural system that provides forest managers with an alternative to clearcutting. While much of the standing volume is removed in one harvesting operation, residual stems are retained to provide structural complexity and wildlife habitat functions, or to accrue volume before removal during subsequent stand entries. The residual...

Attrition and Retention among Special Education Paraprofessionals

Science.gov (United States)

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…

Peripartal leukogram in cows with and without retained placenta

Directory of Open Access Journals (Sweden)

Lužajić Tijana

2014-01-01

Full Text Available The aim of this study was to investigate whether prepartal leukogram in cows with retained placenta could indicate the presence of subclinical systemic inflammatory response before the onset of disease. After calving, sixteen highly pregnant Holstein cows, aged 3 to 9 years, without clinical signs of the disease prior to calving were divided into two groups: the first group (n=9 were animals without retained placenta, or any visible inflammation after birth; the second group (n=7 were cows with retained placenta. Blood was sampled three times before parturition, at intervals of one week, and once 24 hours after birth. The number of total leukocytes, segmented and non segmented neutrophilic granulocytes (NG, lymphocytes and monocytes were determined by standard laboratory techniques. The results have shown that in the group of cows with retained placenta the number of mature neutrophils was slightly elevated in the third, second and last week before calving, and equal number of non segmented neutrophils in regard to the group with no retention. The results have also shown that, in both groups of cows, 24 hours after calving, the number of total leukocytes and the number of segmented neutrophils decreased, but the number of the non segmented neutrophils increased. Based on this, we can conclude that cows with retained placenta had no systemic inflammatory response during three weeks prepartal period, but 24 hours after calving, systemic inflammatory response was documented in all the cows. Moreover, the intensity of inflammatory response in cows with retained placenta was not more pronounced in comparison to cows without retained placenta. [Projekat Ministarstva nauke Republike Srbije, br. 175061

Total rewards that retain: A study of demographic preferences

Directory of Open Access Journals (Sweden)

Monica Pregnolato

2017-01-01

Full Text Available Orientation: Changing workplace demographics and a dearth of employees with scarce skills have forced employers to better understand the various factors that retain talented employees. Research purpose: In this empirical study, the reward preferences and ideal combination of total reward elements (based on an estimation of their relative importance that retain employees from various demographic groups, including employees of different race, gender and age groups, were investigated. Motivation for study: Organisations are competing for talented employees and to benefit from the value these individuals add, it is required of them to stay at the respective businesses. Previous studies have indicated that employees who are offered a reward package that is aligned to their personal preferences are prone to stay longer at the organisation and to be more engaged at work. However, new and novel ways need to be found to identify the reward preferences of employees. Research design, approach and method: A quantitative approach and descriptive research design was employed to estimate the individual reward preferences and identify an ideal mix of total reward elements that retain different cohorts of employees. Three questionnaires were distributed, including a Remuneration Managers Questionnaire (n = 7, a Remuneration Preference Questionnaire (n = 368 and a Choice-based Conjoint Task Questionnaire (n = 368. The latter two questionnaires were distributed as an online questionnaire to South African businesses and consisted of eight choice-based conjoint tasks, as well as a field survey. Main findings: The results of the choice-based conjoint analysis revealed that all respondents considered financial rewards (Benefits, Performance and Recognition, Remuneration, Career, in that order as relatively speaking, the most important components in their total rewards package that would lead to their retention. For most demographic groups, the remaining three places

Effect of Grade Retention in First Grade on Psychosocial Outcomes

OpenAIRE

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 var...

Biofilm formation on stainless steel and gold wires for bonded retainers in vitro and in vivo and their susceptibility to oral antimicrobials

NARCIS (Netherlands)

Jongsma, Marije A.; Pelser, Floris D. H.; van der Mei, Henny C.; Atema-Smit, Jelly; van de Belt-Gritter, Betsy; Busscher, Henk J.; Ren, Yijin

OBJECTIVE: Bonded retainers are used in orthodontics to maintain treatment result. Retention wires are prone to biofilm formation and cause gingival recession, bleeding on probing and increased pocket depths near bonded retainers. In this study, we compare in vitro and in vivo biofilm formation on

Proteinuric diseases with sodium retention: Is plasmin the link?

DEFF Research Database (Denmark)

Svenningsen, Per; Skøtt, Ole; Jensen, Boye L

2012-01-01

1. Sodium retention in disease states characterized by proteinuria, such as nephrotic syndrome, preeclampsia, and diabetic nephropathy, occurs through poorly understood mechanism(s). 2. In the nephrotic syndrome, data from experimental and clinical studies indicate that the sodium retention...... originates in the renal cortical collecting duct and involves hyper-activity of the epithelial sodium channel (ENaC). 3. The stimulus for the increased ENaC activity does not appear to involve any of the classical sodium retaining mechanisms, such as the renin-angiotensin-aldosterone system, arginine...... and diabetic nephropathy, which are also characterized by proteinuria and sodium retention. 7. In this review, we will examine the evidence for a role of urinary serine protease activity in the development of sodium and water retention in diseases characterised by proteinuria with a focus on the nephrotic...

Aroma retention during the drying of liquid foods

NARCIS (Netherlands)

Menting, L.C.; Hoogstad, B.; Thijssen, H.A.C.

1970-01-01

Factors detg. aroma retention during the drying of food liqs. were investigated by a model system. Slabs of an aq. soln. of partially hydrolyzed starch, contg. a small amt. of acetone, were dried in air and the percentage of acetone retained was measured. Acetone was lost almost exclusively during

Increasing Retention and Graduation Rates through a STEM Learning Community

Science.gov (United States)

Dagley, Melissa; Georgiopoulos, Michael; Reece, Amber; Young, Cynthia

2016-01-01

The EXCEL Program began as a National Science Foundation-sponsored STEM Talent Expansion Program in 2006 and, because of its significant impact on retention of STEM majors, has since become an institutionalized program at the University of Central Florida. The University of Central Florida EXCEL Program annually recruits approximately 200…

LEO P: HOW MANY METALS CAN A VERY LOW MASS, ISOLATED GALAXY RETAIN?

Energy Technology Data Exchange (ETDEWEB)

McQuinn, Kristen B. W.; Skillman, Evan D. [Minnesota Institute for Astrophysics, School of Physics and Astronomy, 116 Church Street, S.E., University of Minnesota, Minneapolis, MN 55455 (United States); Dolphin, Andrew [Raytheon Company, 1151 E. Hermans Road, Tucson, AZ 85756 (United States); Cannon, John M. [Department of Physics and Astronomy, Macalester College, 1600 Grand Avenue, Saint Paul, MN 55105 (United States); Salzer, John J.; Rhode, Katherine L. [Department of Astronomy, Indiana University, 727 East 3rd Street, Bloomington, IN 47405 (United States); Adams, Elizabeth A. K. [ASTRON, the Netherlands Institute for Radio Astronomy, Postbus 2, 7990 AA, Dwingeloo (Netherlands); Berg, Danielle [Center for Gravitation, Cosmology and Astrophysics, Department of Physics, University of Wisconsin Milwaukee, 1900 East Kenwood Boulevard, Milwaukee, WI 53211 (United States); Giovanelli, Riccardo; Haynes, Martha P., E-mail: kmcquinn@astro.as.utexas.edu [Center for Radiophysics and Space Research, Space Sciences Building, Cornell University, Ithaca, NY 14853 (United States)

2015-12-20

Leo P is a gas-rich dwarf galaxy with an extremely low gas-phase oxygen abundance (3% solar). The isolated nature of Leo P enables a quantitative measurement of metals lost solely due to star formation feedback. We present an inventory of the oxygen atoms in Leo P based on the gas-phase oxygen abundance measurement, the star formation history (SFH), and the chemical enrichment evolution derived from resolved stellar populations. The SFH also provides the total amount of oxygen produced. Overall, Leo P has retained 5% of its oxygen; 25% of the retained oxygen is in the stars while 75% is in the gas phase. This is considerably lower than the 20%–25% calculated for massive galaxies, supporting the trend for less efficient metal retention for lower-mass galaxies. The retention fraction is higher than that calculated for other alpha elements (Mg, Si, Ca) in dSph Milky Way satellites of similar stellar mass and metallicity. Accounting only for the oxygen retained in stars, our results are consistent with those derived for the alpha elements in dSph galaxies. Thus, under the assumption that the dSph galaxies lost the bulk of their gas mass through an environmental process such as tidal stripping, the estimates of retained metal fractions represent underestimates by roughly a factor of four. Because of its isolation, Leo P provides an important datum for the fraction of metals lost as a function of galaxy mass due to star formation.

Expression of oxytocin receptors is greatly reduced in the placenta of heavy mares with retained fetal membranes due to secondary uterine atony.

Science.gov (United States)

Rapacz-Leonard, A; Raś, A; Całka, J; Janowski, T E

2015-09-01

Fetal membrane retention can be a life-threatening condition and its incidence exceeds 50% in heavy draught mares. Although fetal membrane retention is commonly treated with repeated injections of oxytocin, based on the suggestion that it is caused mainly by secondary atony of the uterus, this treatment sometimes fails. This led us to ask if expression of oxytocin receptors differs in mares that retain fetal membranes due to secondary uterine atony. To determine whether expression of oxytocin receptors in equine placental tissues differs when heavy draught mares expel fetal membranes or retain them because of secondary uterine atony. Controlled study using archived tissues. Placental biopsies (containing the endometrium and allantochorion) were taken from 8 heavy draught mares during parturition. Four mares expelled fetal membranes shortly after foaling (control mares) and 4 mares retained them (expulsion time was >3 h from delivery). The 4 mares that retained fetal membranes had secondary atony of the uterus. The amount of oxytocin receptors was estimated by measuring the intensity of western blot bands. The presence and location of oxytocin receptors were determined by immunocytochemistry. Oxytocin receptor expression was nearly 50 times less intense in mares with placenta retention due to secondary atony of the uterus and immunocytochemical staining was barely visible. In the control mares, oxytocin receptors were found in both epithelial and endothelial cells of the placenta and staining was most intense where the endometrium contacts the allantochorion. Inadequate expression of oxytocin receptors may be a cause of uterine atony leading to fetal membrane retention. © 2015 EVJ Ltd.

Optimization of an M/M/1/N Feedback Queue with Retention of Reneged Customers

Directory of Open Access Journals (Sweden)

Rakesh Kumar

2014-01-01

Full Text Available Customer impatience has become a threat to the business world. Firms employ various customer retention strategies to retain their impatient (or reneged customers. Customer retention mechanisms may help to retain some or all impatient customers. Further, due to unsatisfactory service, customers may rejoin a queue immediately after departure. Such cases are referred to as feedback customers. Kumar and Sharma take this situation into account and study an M/M/1/N feedback queuing system with retention of reneged customers. They obtain only a steady-state solution for this model. In this paper, we extend the work of Kumar and Sharma by performing an economic analysis of the model. We develop a model for the costs incurred and perform the appropriate optimization. The optimum system capacity and optimum service rate are obtained. (original abstract

In vivo biofilm formation on stainless steel bonded retainers during different oral health-care regimens

NARCIS (Netherlands)

Jongsma, Marije A.; van der Mei, Henny C.; Atema-Smit, Jelly; Busscher, Henk I.; Ren, Yijin

2015-01-01

Retention wires permanently bonded to the anterior teeth are used after orthodontic treatment to prevent the teeth from relapsing to pre-treatment positions. A disadvantage of bonded retainers is biofilm accumulation on the wires, which produces a higher incidence of gingival recession, increased

Information Technology Strategies for Honor Society and Organization Membership Retention in Online Nursing Programs.

Science.gov (United States)

Hopkins, Emily E; Wasco, Jennifer J

Membership retention in an honor society or organization is of utmost importance for sustainability. However, retaining members in organizations that serve online education nursing students can be a challenging task. Understanding the importance of creating a sense of community to promote retention within an honor society chapter, nursing faculty at a small private university implemented different online approaches. This article highlights successful information technology strategies to promote membership retention in organizations for online nursing students.

Retention factors in relation to organisational commitment in medical and information technology services

Directory of Open Access Journals (Sweden)

Jeannette van Dyk

2012-07-01

Research purpose: The objectives of the study were to investigate empirically: (1 the relationship between employees’ satisfaction with organisational retention factors (measured by the Retention Factors Scale and their organisational commitment (measured by the Organisational Commitment Questionnaire and (2 whether gender, age, race and tenure groups differ significantly in terms of these variables. Motivation for the study: Medical and information technology professionals have specialised and hard to replace skills. They also have strong tendencies to leave their organisations and countries. Understanding the retention factors that will increase their organisational commitment may benefit the organisations who want to retain their valuable talent. Research design, approach and method: The researchers used a cross-sectional survey design to collect data from a purposive sample of 206 staff members who had scarce skills in a South African medical and information technology services company. Correlational and inferential statistics were computed to achieve the objectives. Main findings: The results showed that the participants’ satisfaction with retention factors has a significant relationship with their organisational commitment and that the biographical groups differ significantly in terms of the variables. Practical/managerial implications: The measured retention factors were all associated with human resource management practices that influence employees’ intentions to leave. Contribution/value-add: The results are important to managers who are interested in retaining staff who have scarce skills and provide valuable pointers for designing effective retention strategies.

Long Term Retention of Deuterium and Tritium in Alcator C-Mod

International Nuclear Information System (INIS)

FIORE, C.; LABOMBARD, B.; LIPSCHULTZ, B.; PITCHER, C.S.; SKINNER, C.H.; WAMPLER, WILLIAM R.

1999-01-01

We estimate the total in-vessel deuterium retention in Alcator C-Mod from a run campaign of about 1090 plasmas. The estimate is based on measurements of deuterium retained on 22 molybdenum tiles from the inner wall and divertor. The areal density of deuterium on the tiles was measured by nuclear reaction analysis. From these data, the in-vessel deuterium inventory is estimated to be about 0.1 gram, assuming the deuterium coverage is toroidally symmetric. Most of the retained deuterium is on the walls of the main plasma chamber, only about 2.5% of the deuterium is in the divertor. The D coverage is consistent with a layer saturated by implantation with ions and charge-exchange neutrals from the plasma. This contrasts with tokamaks with carbon plasma-facing components (PFC's) where long-term retention of tritium and deuterium is large and mainly in the divertor due to codeposition with carbon eroded by the plasma. The low deuterium retention in the C-Mod divertor is mainly due to the absence of carbon PFC's in C-Mod and the low erosion rate of Mo

Climatic variability and its role in regulating C, N and P retention in the James River Estuary

Science.gov (United States)

Bukaveckas, Paul A.; Beck, Michael; Devore, Dana; Lee, William M.

2018-05-01

Transformations and retention of C, N and P inputs to estuaries are subject to external factors such as discharge-driven variation in loading rates, and internal processes regulating biogeochemical cycles. We used an 8-year time series of finely resolved (monthly) mass balances for the tidal freshwater segment of the James River Estuary to assess the influence of discharge and temperature on C, N and P retention. Peak export and retention of organic, likely particulate, fractions occurred in months of highest discharge. With increasing discharge we observed higher mass retention, greater proportional retention (in relation to inputs) and more selective retention (with P retained preferentially over N and C). DIN retention was strongly influenced by water temperature with 10-fold high retention occurring at high (>20 °C) vs. low (estuaries is in dissolved inorganic form, and therefore subject to temperature dependent rates of biological assimilation and denitrification. By contrast, the bulk of the P load was in particulate form, which is retained via sediment trapping, and not appreciably affected by water temperature. The tidal freshwater estuary was an important site for nutrient removal where the accumulation of N- and P- rich materials may delay recovery in response to nutrient load reductions.

Retention assessment of magnetic nanoparticles in rat arteries with micro-computed tomography.

Science.gov (United States)

Tu, Shu-Ju; Wu, Siao-Yun; Wang, Fu-Sheng; Ma, Yunn-Hwa

2014-03-07

Magnetic nanoparticles (MNPs) may serve as carriers for pharmacological agents to the target in a magnetic-force guiding system. It is essential to achieve effective retention of MNPs through the external magnet placement. However, it is difficult to estimate the retention efficiency of MNPs and validate the experimental strategies. Micro-CT was used to identify the spatial distribution of MNP retention and image analysis is then extended to evaluate the MNP delivery efficiency. Male Sprague Dawley rats were anesthetized to expose abdominal arteries with an NdFeB magnet of 4.9 kG placed by the left iliac artery. After a 20 min equilibrium period, arteries were ligated, removed and fixed in a paraformaldehyde solution. Experiments were performed with intravenous injection in our platform with two independent groups. MNPs were used in the first group, while chemical compounds of recombinant tissue plaminogen activator were attached to MNPs as rtPA (recombinant tissue plaminogen activator)-MNPs in the second group. Image analysis of micro-CT shows the average retention volume of MNPs and rtPA-MNPs in the left iliac arteries is 9.3 and 6.3 fold of that in the right. Large local aggregation of MNPs and rtPA-MNPs in the left iliac arteries is the consequence of external magnet placement, suggesting feasibility of magnetic targeting through the intravenous administration. We also determined that on average 0.57% and 0.064% of MNPs and rtPA-MNPs respectively were retained in the left iliac artery. It was estimated that the average rtPA concentration of 60.16 µg mL(-1) may be achieved with rtPA-MNPs. With the micro-CT imaging approach, we accomplished visualization of the aggregation of retained particles; reconstructed 3D distribution of relative retention; estimated the average particle number of local retention; determined efficiency of targeted delivery. In particular, our quantitative image assessment suggests that intravenous administration of rtPA-MNPs may retain

True retention of nutrients on cooking of Australian retail lamb cuts of differing carcass classification characteristics.

Science.gov (United States)

Kosulwat, Somkiat; Greenfield, Heather; Buckle, Kenneth A

2003-12-01

The true retention of nutrients (proximate principles and cholesterol) on cooking of three retail cuts from lambs classified by weight, sex and fatness score was investigated. Fat retentions of the total cut and of the lean portion of lamb legs and mid-loin chops were not affected by carcass fatness, weight and sex or their interactions, however, the fat retention of the total cut and of the lean portion of forequarter chops was affected by fat score, with forequarter chops from fat score 1 retaining more fat than did chops of carcasses of higher fat score. Overall, fat was lost by all cuts (total cut) on cooking, with only 70-80% of fat being retained, but fat content of lean only increased on cooking (retention >100%), indicating the passage of fat into the lean portion from the external fat cover during the cooking process. Carcass factors and their interactions had little or no effect on the protein, water and ash retentions of the total cut or the lean portions of the three cuts. Cholesterol retention by the lean portion of three cooked lamb cuts was not affected by any carcass factors or their interactions. Cholesterol retentions were ∼99% for total cuts and tended to be ∼102% for the lean portions.

Six-year clinical outcome of single implant-retained mandibular overdentures--a pilot study.

Science.gov (United States)

Passia, Nicole; Wolfart, Stefan; Kern, Matthias

2015-10-01

The aim of this prospective pilot study was to evaluate the prosthodontic maintenance as well as the implant outcome of single implant-retained mandibular overdentures over an observation period of 6 years. Eleven edentulous patients received one single implant in the midline of the mandible. Denture bases were temporarily relined and 2 months later provided with a ball attachment for implant retention. Implant related parameters and prosthodontic maintenance interventions were assessed 4 weeks after implant loading and then once a year. Over a mean observation period of 75.9 months, no implant was lost. The most frequent prosthetic maintenance intervention was activation of the matrix due to loss of retention, followed by exchange of the female part. Eight denture bases had to be repaired after a fracture in the midline area. Within the limitations of this preliminary clinical study, the concept of a single midline implant to retain a mandibular complete denture was a successful treatment option for elderly edentulous patients. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Are Flunkers Social Outcasts? A Multilevel Study of Grade Retention Effects on Same-Grade Friendships

Science.gov (United States)

Demanet, Jannick; Van Houtte, Mieke

2016-01-01

We examine the association between grade retention and the number of same-grade friendships. Moreover, we investigate the effect of a school's proportion of retained students on these friendships and the moderating effect of this school characteristic on the relationship between retention and the number of same-grade friendships. Multilevel…

Employee Retention Strategies : the case of a patent firm in Australia

OpenAIRE

Ahmad, Khalid; Azumah, Kenneth

2012-01-01

Retaining employees is an important goal of every organization. This thesis explores the factors that can significantly impact employee retention in an organisation. It attempts to relate some of the factors discovered to major theories such as the Employee Equity Model, Herzberg’s (Two-Factor) Theory and the Job Embeddedness Theory. The literature surveyed by this study mention employee motivation, job satisfaction and job embeddedness as the main factors that influence employee retention ra...

Patient retention at dental school clinics: a marketing perspective.

Science.gov (United States)

Makarem, Suzanne C; Coe, Julie M

2014-11-01

The purpose of this investigation was to examine the drivers of patient retention at dental school clinics from a services marketing perspective. An analysis of patient characteristics at Virginia Commonwealth University School of Dentistry, screened between August 2010 and July 2011 (N=3604), was performed using descriptive statistics, cross-tabulations, and a binary logistic regression. The main findings were that 42 percent of patients in the study were retained and that no response to communication efforts (36 percent) and financial problems (28 percent) constituted the most common reasons for non-retention. Older age, having insurance, and living within a sixty-mile radius were significant drivers of retention (pskills to better service them, and consequently increasing retention. This will lead to providing a continuum of care and student education and to ensuring the sustainability and quality of the school's educational programs.

Factors affecting the retention of Generation X public servants: An exploratory study

Directory of Open Access Journals (Sweden)

Vhutshilo Masibigiri

2011-03-01

Purpose: The purpose of this study was to explore the factors that affect the retention of Generation X public servants. Motivation for the study: Given their unique characteristics, it is a challenge to retain Generation X employees. This problem may be worse in the public sector than in the private sector, as there are fewer financial rewards in the public service than in the private sector. Research design: The interpretivist paradigm is appropriate for this study. It used a qualitative, empirical approach. The researchers obtained the data through purposive sampling and interviews. Main findings: The study showed that the factors affecting the retention of Generation X public servants include work content, utilisation of skills, career advancement, work–life balance, compensation, security needs, leadership and drive. Practical/managerial implications: Employers, like the civil service, can be proactive in retaining Generation X employees because of the factors that affect their retention. Managers can prevent further pressure on service delivery that the skills shortage has caused if they use the skills the employees already have. Contribution: The article fills a gap, as there has been little research on staff retention. This is particularly true of Generation X employees in South Africa. This article adds information that will improve retention strategies for Generation X employees, particularly in the public service.

Fission product retention during faults involving steam generator tube rupture

International Nuclear Information System (INIS)

Rodliffe, R.S.

1983-08-01

In some PWR fault conditions, such as stuck open safety relief valve in the secondary circuit or main steam line break, the release of fission products to the atmosphere may be increased by the leakage of primary coolant into the secondary circuit following steam generator tube rupture. The release may be reduced by retention either within the primary circuit or within the affected steam generator unit (SGU). The mechanisms leading to retention are reviewed and quantified where possible. The parameters on which any analysis will be most critically dependent are identified. Fission product iodine and caesium may be retained in the secondary side of a SGU either by partition to retained water or by droplet deposition on surfaces and subsequent evaporation to dryness. Two extreme simplifications are considered: SGU 'dry', i.e. the secondary side is steam filled, and SGU 'wet', i.e. the tube bundle is covered with water. Consideration is given to: the distribution of fission products between gaseous and aerosol forms; mechanisms for droplet formation, deposition and resuspension; fission product retention during droplet or film evaporation primary coolant mixing and droplet scrubbing in a wet SGU; and the performance of moisture separators and steam driers. (author)

Customer retention: A theoretical perspective of service failure and service recovery in the hotel industry

Directory of Open Access Journals (Sweden)

D. J. Petzer

2006-12-01

Full Text Available Purpose: The purpose of this paper is to provide a theoretical perspective on customer retention activities associated with service failure management and service recovery as a means to retain customers in the hotel industry - and to improve the competitiveness of a hotel. The research is pursued with the following objectives in mind: To determine the customer retention activities involved in the service failure management needed by hotels to retain customers. To determine the customer retention activities associated with the service recovery that hotels might perform in order to retain customers. Design/methodology/approach: Secondary sources such as textbooks, scientific journals, and previous studies on the subject were used to obtain relevant background information. A literature search of secondary sources was conducted to elucidate questions and areas of enquiry that relate to the research. Findings: The theoretical perspectives on service failure management and service recovery provided in this paper suggest several customer retention activities that might be used by hotels in order to manage service failure and service recovery - and thus become more competitive. Implications: This paper suggests a number of approaches that hotel managers might take to improve service failure management and service recovery. Such activities could assist a hotel in determining where it is lacking and where to improve its performance in these areas. These activities could provide guidance to managers who are dealing with the day-to-day operations of a hotel. They might help to avoid service failures in the first place, and, secondly, to give ideas about service recovery if failures do occur. On a more strategic level, these activities could also assist managers to develop a general customer retention strategy that incorporates service failure management and service recovery. Originality/value: Service failure management and service recovery are viewed as

One-year retention of general and sequence-specific skills in a probabilistic, serial reaction time task.

Science.gov (United States)

Romano, Jennifer C; Howard, James H; Howard, Darlene V

2010-05-01

Procedural skills such as riding a bicycle and playing a musical instrument play a central role in daily life. Such skills are learned gradually and are retained throughout life. The present study investigated 1-year retention of procedural skill in a version of the widely used serial reaction time task (SRTT) in young and older motor-skill experts and older controls in two experiments. The young experts were college-age piano and action video-game players, and the older experts were piano players. Previous studies have reported sequence-specific skill retention in the SRTT as long as 2 weeks but not at 1 year. Results indicated that both young and older experts and older non-experts revealed sequence-specific skill retention after 1 year with some evidence that general motor skill was retained as well. These findings are consistent with theoretical accounts of procedural skill learning such as the procedural reinstatement theory as well as with previous studies of retention of other motor skills.

Clinical trials: the challenge of recruitment and retention of participants.

Science.gov (United States)

Gul, Raisa B; Ali, Parveen A

2010-01-01

This article, based on the available literature, attempts to discuss the importance of recruitment and retention of research participants, the associated barriers and challenges, and various strategies to overcome these barriers. The inability to recruit and retain the required participants in a research project poses serious threats to both the internal and the external validity of a research study. Despite serious implications, the issues of recruitment and retention do not receive due attention in research and publications. Literature suggests a lack of coordinated efforts to collect information on the outcomes of recruitment experiences in clinical trials and population studies. Studies often mention the number of participants who refuse to participate; however, the majority of the studies often fail to mention the specific reasons insufficient recruitment or retention of the participants. A methodological paper. Various participant-, context-, environment- and research-related factors are examined that affect the phenomenon of recruitment and retention of the participants in a study. Delayed or inefficient recruitment also has financial and ethical implications. Although there are many pieces of information scattered throughout academic journals on recruitment and retention of participants in research, few authors have dealt with the issue holistically. It is imperative for researchers to understand the importance of recruitment and retention of research participants, the associated barriers and challenges, and various strategies to overcome these barriers. Appropriate recording and reporting of the problems faced while recruiting and retaining the participants in research studies can help not only in understating the challenge, but will also help in devising the strategies to overcome this problem. This article was an attempt to synthesise and review the available literature on recruitment and retention issues, which demand extensive theoretical and

Depression and Self-Concept: Personality Traits or Coping Styles in Reaction to School Retention of Hispanic Adolescents

Directory of Open Access Journals (Sweden)

Rebecca A. Robles-Piña

2011-01-01

Full Text Available The purpose of this study was to investigate whether depression and self-concept could be construed as personality characteristics and/or coping styles in reaction to school retention or being held back a grade. The participants in this study were 156 urban Hispanic adolescents, ages 12–18, and of these, 51 or 33% had been retained in school. Students who had been retained reported a lower self-concept score, higher GPA, and higher rates of depression, and they were more likely to be male than students who had not been retained. The findings of this study indicated that self-concept was a personality characteristic that, due to its malleability, is also a coping style in regards to retention with this Hispanic adolescent population.

Retention of low-level radioacrive waste material by soil

International Nuclear Information System (INIS)

Essington, E.H.; Fowler, E.B.; Polzer, W.L.

1979-01-01

Beacuse of the wide variations in soil and waste characteristics, the degree of radionuclide retention would be expected to vary; knowledge of that variation may be of value in predicting radionuclde mobility. This report discusses results of investigations of radioactive waste/soil interactions as they relate to radionucldie retention and its variability among soils and radionuclides. In soil column leaching studies, radioactive waste solutions were applied to four different soil types; 241 Am, 88 Y, and 172 Hf were retained in the top four cm of soil with better than 90% retained by a protective surface sand layer. Less than 50% of the 85 Sr, 137 Cs, and 83 Rb was retained by the surface sand. No 88 Y, 172 Hf, 85 Sr, 137 Cs, or 83 Rb was detected by gamma counting in the leachate solutions, however, using a more sensitive analytical technique small amounts of 238 Pu, 239 240 Pu and 241 Am were found in leachates from all soils. It appears that release of this small fraction of mobile radionuclide may have a significant long-term impact on the environment. It aslo appears that reliance for attenuation of some radionuclides can not be placed solely on characteristics of the soil matrix

Sequence features responsible for intron retention in human

Directory of Open Access Journals (Sweden)

Sakabe Noboru

2007-02-01

Full Text Available Abstract Background One of the least common types of alternative splicing is the complete retention of an intron in a mature transcript. Intron retention (IR is believed to be the result of intron, rather than exon, definition associated with failure of the recognition of weak splice sites flanking short introns. Although studies on individual retained introns have been published, few systematic surveys of large amounts of data have been conducted on the mechanisms that lead to IR. Results TTo understand how sequence features are associated with or control IR, and to produce a generalized model that could reveal previously unknown signals that regulate this type of alternative splicing, we partitioned intron retention events observed in human cDNAs into two groups based on the relative abundance of both isoforms and compared relevant features. We found that a higher frequency of IR in human is associated with individual introns that have weaker splice sites, genes with shorter intron lengths, higher expression levels and lower density of both a set of exon splicing silencers (ESSs and the intronic splicing enhancer GGG. Both groups of retained introns presented events conserved in mouse, in which the retained introns were also short and presented weaker splice sites. Conclusion Although our results confirmed that weaker splice sites are associated with IR, they showed that this feature alone cannot explain a non-negligible fraction of events. Our analysis suggests that cis-regulatory elements are likely to play a crucial role in regulating IR and also reveals previously unknown features that seem to influence its occurrence. These results highlight the importance of considering the interplay among these features in the regulation of the relative frequency of IR.

Winning the Retention Wars. The USAF, Women Officers and the Need for Transformation

National Research Council Canada - National Science Library

DiSilverio, Laura

2002-01-01

This paper establishes the need to retain more women Air Force officers longer, analyzes survey results revealing women's reasons for separating from the Air Force, and recommends specific retention...

Prolonged Intrauterine Retention of Foetal Bones after Midtrimester ...

African Journals Online (AJOL)

Prolonged retention of foetal bones in the uterus is a rare complication of induced abortion. We present the case of a 37 year old nullipara with retained foetal bones following a second trimester induced abortion. Accurate diagnosis and removal of the bony fragments led to restoration of fertility and subsequent delivery of a ...

Fuel retention in JET ITER-Like Wall from post-mortem analysis

Energy Technology Data Exchange (ETDEWEB)

Heinola, K., E-mail: kalle.heinola@ccfe.ac.uk [Association EURATOM-TEKES, University of Helsinki, PO Box 64, 00560 Helsinki (Finland); EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Widdowson, A. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Likonen, J. [Association EURATOM-TEKES, VTT, PO Box 1000, 02044 VTT, Espoo (Finland); Alves, E. [Instituto Superior Tecnico, Instituto de Plasmas e Fusao Nuclear, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Baron-Wiechec, A. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Barradas, N. [Instituto Superior Tecnico, Instituto de Plasmas e Fusao Nuclear, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Brezinsek, S. [Forschungszentrum Julich GmbH, EURATOM Association, D-52425 Julich (Germany); Catarino, N. [Instituto Superior Tecnico, Instituto de Plasmas e Fusao Nuclear, Universidade de Lisboa, 1049-001 Lisboa (Portugal); Coad, P. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Koivuranta, S. [Association EURATOM-TEKES, VTT, PO Box 1000, 02044 VTT, Espoo (Finland); Matthews, G.F. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Mayer, M. [Max-Planck Institut fur Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Petersson, P. [Royal Institute of Technology, Association EURATOM-VR, SE-10044 Stockholm (Sweden)

2015-08-15

Selected Ion Beam Analysis techniques applicable for detecting deuterium and heavier impurities have been used in the post-mortem analyses of tiles removed after the first JET ITER-Like Wall (JET-ILW) campaign. Over half of the retained fuel was measured in the divertor region. The highest figures for fuel retention were obtained from regions with the thickest deposited layers, i.e. in the inner divertor on top of tile 1 and on the High Field Gap Closure tile, which resides deep in the plasma scrape-off layer. Least retention was found in the main chamber high erosion regions, i.e. in the mid-plane of Inner Wall Guard Limiter. The fuel retention values found typically varied with deposition layer thicknesses. The reported retention values support the observed decrease in fuel retention obtained with gas balance experiments of JET-ILW.

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

International Nuclear Information System (INIS)

Mendoza, D.P.; Mahoney, L.A.; Gauglitz, P.A.; Rassat, S.D.; Caley, S.M.

1999-01-01

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 (Alleinann 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

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

Energy Technology Data Exchange (ETDEWEB)

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

Rehabilitation of a Patient with an Intra Oral Prosthesis and an Extra Oral Orbital Prosthesis Retained with Magnets

OpenAIRE

Pattanaik, Seema; Wadkar, Aarti P.

2011-01-01

This clinical case report deals with a rehabilitation of a patient with an extensive maxillary and orbital defect using an intra oral prosthesis obturating the maxillary defect and extra oral orbital prosthesis retained with rare-earth magnets for secondary retention; primary retention was derived by snug fit of the prosthesis to underlying and adjacent tissues. The rehabilitation resulted in improved function, esthetics and comfort to the patient thus enabling him to lead a normal life.

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

Energy Technology Data Exchange (ETDEWEB)

Meyer, P.A.; Brewster, M.E.; Bryan, S.A. [and others

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.

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

International Nuclear Information System (INIS)

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

Beyond the retention-acquisition trade-off : capabilities of ambidextrous sales organizations

NARCIS (Netherlands)

Nijssen, E.J.; Guenzi, P.; van der Borgh, W.

2017-01-01

Sales organizations aim to grow their firms' business by acquiring new customers while retaining their existing ones. Although customer acquisition and retention are complementary processes, they involve different sales process capabilities that often compete for investments. However, firms that

Retainer Positioner

Directory of Open Access Journals (Sweden)

Sanjeeb Kumar Sahu

2012-01-01

Full Text Available Several techniques are used to keep the retainer wire in the proper position during direct bonding, of lingual bonded retainers. Proper placement helps prevent occlusal wear of the composite over the retainer wire, thus reducing the risk of breakage. This article describes a new chairside time saving retainer positioner which allows accurate placement and direct bonding of all types of fixed lingual retainers, with solid or multistranded wires.

Actual Drawing of Histological Images Improves Knowledge Retention

Science.gov (United States)

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

2016-01-01

Medical students have to process a large amount of information during the first years of their study, which has to be retained over long periods of nonuse. Therefore, it would be beneficial when knowledge is gained in a way that promotes long-term retention. Paper-and-pencil drawings for the uptake of form-function relationships of basic tissues…

Transparent hydrogel with enhanced water retention capacity by introducing highly hydratable salt

Energy Technology Data Exchange (ETDEWEB)

Bai, Yuanyuan; Xiang, Feng; Wang, Hong, E-mail: hwang@mail.xjtu.edu.cn, E-mail: suo@seas.harvard.edu [Electronic Materials Research Laboratory, School of Electronics and Information Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, Baohong; Zhou, Jinxiong [State Key Laboratory for Strength and Vibration of Mechanical Structures, International Center for Applied Mechanics and School of Aerospace, Xi' an Jiaotong University, Xi' an 710049 (China); Suo, Zhigang, E-mail: hwang@mail.xjtu.edu.cn, E-mail: suo@seas.harvard.edu [School of Engineering and Applied Sciences, Kavli Institute of Bionano Science and Technology, Harvard University, Cambridge, Massachusetts 02138 (United States)

2014-10-13

Polyacrylamide hydrogels containing salt as electrolyte have been used as highly stretchable transparent electrodes in flexible electronics, but those hydrogels are easy to dry out due to water evaporation. Targeted, we try to enhance water retention capacity of polyacrylamide hydrogel by introducing highly hydratable salts into the hydrogel. These hydrogels show enhanced water retention capacity in different level. Specially, polyacrylamide hydrogel containing high content of lithium chloride can retain over 70% of its initial water even in environment with relative humidity of only 10% RH. The excellent water retention capacities of these hydrogels will make more applications of hydrogels become possible.

Transparent hydrogel with enhanced water retention capacity by introducing highly hydratable salt

International Nuclear Information System (INIS)

Bai, Yuanyuan; Xiang, Feng; Wang, Hong; Chen, Baohong; Zhou, Jinxiong; Suo, Zhigang

2014-01-01

Polyacrylamide hydrogels containing salt as electrolyte have been used as highly stretchable transparent electrodes in flexible electronics, but those hydrogels are easy to dry out due to water evaporation. Targeted, we try to enhance water retention capacity of polyacrylamide hydrogel by introducing highly hydratable salts into the hydrogel. These hydrogels show enhanced water retention capacity in different level. Specially, polyacrylamide hydrogel containing high content of lithium chloride can retain over 70% of its initial water even in environment with relative humidity of only 10% RH. The excellent water retention capacities of these hydrogels will make more applications of hydrogels become possible.

Influence of pH on retention of camel chymosin in curd

DEFF Research Database (Denmark)

Børsting, Mette Winther; Qvist, Karsten B.; Ardö, Ylva Margareta

2014-01-01

Retained coagulant in cheese initiates casein breakdown and influences cheese structure and flavour formation. This study investigated the influence of milk pH on retention of camel chymosin in curd and compared it with bovine chymosin. Milk at five different pH levels was coagulated with same...... coagulation activity. The retention of camel chymosin in curd was rather constant at ∼20% between pH 6.65 and 6.00, while it increased almost linear from 2 to 21% for bovine chymosin. The lower pH dependence for retention of camel chymosin than of bovine chymosin may be explained by a lower negative charge...

Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics

DEFF Research Database (Denmark)

Arnold, Dario; Dalstra, Michel; Verna, Carlalberta

2016-01-01

Objective: Movements of teeth splinted by fixed retention wires after orthodontic treatment have been observed. The aetiological factors for these movements are unknown. The aim of this in vitro study was to compare the resistance to torque of different stainless steel wires commonly used for fixed...... retainers in orthodontics. Materials and Methods: Torquing moments acting on a retainer wire were measured in a mechanical force testing system by applying buccal crown torque to an upper lateral incisor in both a 3-teeth and in a 2-teeth setup. Seven stainless steel wires with different shape, type (plain...... or a braided 0.016 × 0.022-inch stainless steel wire. A tooth attached by a retainer wire to only one neighbouring tooth is less resistant to torque than a tooth connected to two neighbouring teeth. Annealing a retainer wire with a flame reduces the stiffness of the wire markedly and can lead to a non...

Retention of radium from thermal waters on sand filters and adsorbents

Energy Technology Data Exchange (ETDEWEB)

Elejalde, C. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain)]. E-mail: inpelsac@bi.ehu.es; Herranz, M. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Idoeta, R. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Legarda, F. [Dpto. de Ingenieria Nuclear y Mecanica de Fluidos, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Romero, F. [Dpto. de Ingenieria Quimica y del Medio Ambiente, Escuela Tecnica Superior de Ingenieria, Alameda de Urquijo s/n, 48013 Bilbao (Spain); Baeza, A. [Dpto. de Fisica, Facultad de Veterinaria, Universidad de Extremadura, Avda. Universidad s/n, 10071 Caceres (Spain)

2007-06-18

This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research.

Retention of radium from thermal waters on sand filters and adsorbents

International Nuclear Information System (INIS)

Elejalde, C.; Herranz, M.; Idoeta, R.; Legarda, F.; Romero, F.; Baeza, A.

2007-01-01

This study was focussed on laboratory experiences of retention of radium from one thermal water on sand filters and adsorbents, trying to find an easy method for the elimination in drinkable waters polluted with this natural radio-nuclide. A thermal water from Cantabria (Spain) was selected for this work. Retention experiences were made with columns of 35 mm of diameter containing 15 cm layers of washed river sand or 4 cm layers of zeolite A3, passing known volumes of thermal water at flows between 4 and 40 ml/min with control of the retained radium by determining the amount in the water after the treatment. The statistical analysis of data suggests that retention depends on the flow and the volume passed through the columns. As additional adsorbents were used kaolin and a clay rich in illite. Jar-test experiences were made agitating known weights of adsorbents with the selected thermal water, with addition of flocculants and determination of radium in filtrated water after the treatment. Data suggest that retention is related to the weight of adsorbent used, but important quantities of radium seem remain in solution for higher amounts of adsorbents, according to the statistical treatment of data. The elution of retained radium from columns or adsorbents, previously used in experiences, should be the aim of a future research

Refinements to Service Retention Limits for Reparable Aeronautical Components (Inactive Inventory)

Science.gov (United States)

2014-12-01

Agency DRMS Defense Reutilization and Marketing Service ECDR expected cost to dispose or retain ERL economic retention level ERP enterprise...COLLISION LIGHT (1 OF 2 REQUIRED) AUXILIARY POWER PLANT BEARING MONITOR SYSTEM (BMS) BIM INDICATOR COCKPIT HYDRAULIC QUANTITY INDICATOR SYSTEM

Exploring recruitment, willingness to participate, and retention of low-SES women in stress and depression prevention

Directory of Open Access Journals (Sweden)

Hoefnagels Cees

2010-10-01

Full Text Available Abstract Background Recruitment, willingness to participate, and retention in interventions are indispensable for successful prevention. This study investigated the effectiveness of different strategies for recruiting and retaining low-SES women in depression prevention, and explored which sociodemographic characteristics and risk status factors within this specific target group are associated with successful recruitment and retention. Methods The process of recruitment, willingness to participate, and retention was structurally mapped and explored. Differences between women who dropped out and those who adhered to the subsequent stages of the recruitment and retention process were investigated. The potential of several referral strategies was also studied, with specific attention paid to the use of GP databases. Results As part of the recruitment process, 12.1% of the target population completed a telephone screening. The most successful referral strategy was the use of patient databases from GPs working in disadvantaged neighborhoods. Older age and more severe complaints were particularly associated with greater willingness to participate and with retention. Conclusions Low-SES women can be recruited and retained in public health interventions through tailored strategies. The integration of mental health screening within primary care might help to embed preventive interventions in low-SES communities.

Factors affecting the retention of Generation X public servants: An exploratory study

OpenAIRE

Vhutshilo Masibigiri; Hester Nienaber

2011-01-01

Orientation: Retaining employees, especially Generation Xers, is imperative to ensure the high performance of organisations. Purpose: The purpose of this study was to explore the factors that affect the retention of Generation X public servants. Motivation for the study: Given their unique characteristics, it is a challenge to retain Generation X employees. This problem may be worse in the public sector than in the private sector, as there are fewer financial rewards in the public ...

Retention performance of green roofs in three different climate regions

Science.gov (United States)

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

2016-11-01

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

Effective recruitment and retention strategies in community health programs.

Science.gov (United States)

McCann, Jennifer; Ridgers, Nicola D; Carver, Alison; Thornton, Lukar E; Teychenne, Megan

2013-08-01

The aim of this project was to identify effective recruitment and retention strategies used by health-promotion organisations that focus on increasing physical activity and improving nutrition within the local community. Semistructured telephone or face-to-face interviews with 25 key informants from stakeholder organisations were conducted. Key informants discussed strategies used by their organisation to effectively recruit and retain participants into community-based healthy eating and/or physical activity programs. Transcribed data were analysed with NVivo software. Effective recruitment strategies included word of mouth, links with organisations, dissemination of printed materials, media, referrals, cross-promotion of programs and face-to-face methods. Effective retention strategies included encouraging a sense of community ownership, social opportunities, recruiting a suitable leader and offering flexibility and support. Fees and support for recruiting and retaining participants was also identified. This study provides novel insights to a greatly under researched topic in the field of health promotion. There are two key take-home messages from the present study that are applicable to health practitioners as well as developers and deliverers of community health-promotion programs: (1) it is imperative that all community health organisations report on the effectiveness of their recruitment and retention, both successes and failures; and (2) there is a clear need to tailor the recruitment and retention approach to the target population and the setting the program is occurring in. SO WHAT? These findings provide important insights for the development of future community-based healthy eating and physical activity programs.

Retaining the older workforce: social policy considerations for the universally designed workplace.

Science.gov (United States)

Timmons, Jaimie Ciulla; Hall, Allison Cohen; Fesko, Sheila Lynch; Migliore, Alberto

2011-04-01

Even in the midst of massive layoffs that come with an economic downturn, employers must remain aware of the pending impact of their aging workforce. Losing older employees to retirement drains knowledge and expertise. In response, employers are looking at new ways to retain older workers at the same time that older workers are reevaluating the traditional approach to retirement. This article presents findings from case study research consisting of interviews with key employees at 18 companies in 13 states. Five of those companies subsequently participated in in-person site visits. Interviews were held with a wide range of informants, including company leadership, supervisors, and older workers. Findings include a description of the cultural context within which the development of formal and informal older worker retention strategies occurred, as well as the retention strategies themselves. The discussion section explores the universal nature of these retention initiatives and how consideration of universality benefits not only older workers but a range of diverse groups as well.

The application of talent retention theories in Japan and South Korea

OpenAIRE

Le, Tam

2016-01-01

This report is a study of talent management theory – a new approach to HRM to retain and maximize employees’ potentials, relating practices and to what extend it is applied in Japan and South Korea. To better explain why the implementation of talent retention theory may vary from Western countries or the US, a brief look into East (Confucian) Asian culture was taken, as culture plays a decisive role in human behavior and partly determines the archetypical retention requirements of different c...

Nutrient retention values and cooking yield factors for three South African lamb and mutton cuts.

Science.gov (United States)

van Heerden, Salomina M; Strydom, Phillip E

2017-11-01

Nutrient content of raw and cooked foods is important for formulation of healthy diets. The retention of nutrients during cooking can be influenced by various factors, including animal age, carcass characteristics and cooking method, and these factors are often unique to specific countries. Here the effects of animal age (lamb and mutton) and carcass cut (shoulder, loin and leg) combined with cooking method (moist heat and dry heat) on yield and nutrient retention of selected nutrients of South African sheep carcasses were studied. Cooking yields and moisture retention were lower for lamb loin but higher for lamb leg. Energy and fat retention were higher for all cuts of mutton compared with lamb, while higher retention values for cholesterol were recorded for lamb. Mutton retained more iron (P = 0.10) and zinc and also more vitamin B 2 , B 6 and B 12 than lamb. Shoulder cooked according to moist heat cooking method retained more magnesium, potassium and sodium. Incorporating these retention and yield values into the South African Medical Research Council's Food Composition Tables provides a reliable reference to all concerned with nutrient content of food. It will also guide practitioners and primary industry to adjust animal production aimed at optimum nutrient content to specific diets. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Retenção de metais pesados em micélio de fungos micorrízicos arbusculares Retention of heavy metals by arbuscular mycorrhizal fungi mycelium

Directory of Open Access Journals (Sweden)

Lucélia Cabral

2010-01-01

Full Text Available This work evaluated the kinetics as well as the retention capacity of Cu, Zn, Cd, and Pb by arbuscular mycorrhizal fungi (AMF mycelium. The metal retention is a fast process with Cu being retained 3, 30, and 60 times faster than Zn, Cd, and Pb, respectively. Metal retention capacity varied amongst the different tested AMF species and decreased in the following order: Cu>Zn>>Cd>Pb. The Glomus clarum mycelium showed the highest retention capacity for Cu, Cd and Pb, whereas Zn was mostly retained by Gigaspora gigantea mycelium. The simultaneous application of all tested metals in solution decreased Cu and Zn retention by AMF mycelium. The high retention capacity of Cu and Zn by mycelium of G. clarum and G. gigantea suggests a promising use of these isolates in phytoremediation.

Self-disclosure of HIV status, disclosure counseling, and retention in HIV care in Cameroon.

Science.gov (United States)

Breger, Tiffany L; Newman, Jamie E; Mfangam Molu, Brigitte; Akam, Wilfred; Balimba, Ashu; Atibu, Joseph; Kiumbu, Modeste; Azinyue, Innocent; Hemingway-Foday, Jennifer; Pence, Brian W

2017-07-01

Poor retention in care is common among HIV-positive adults in sub-Saharan Africa settings and remains a key barrier to HIV management. We quantify the associations of disclosure of HIV status and referral to disclosure counseling with successful retention in care using data from three Cameroon clinics participating in the Phase 1 International epidemiologic Databases to Evaluate AIDS Central Africa cohort. Of 1646 patients newly initiating antiretroviral therapy between January 2008 and January 2011, 43% were retained in care following treatment initiation. Self-disclosure of HIV status to at least one person prior to treatment initiation was associated with a minimal increase in the likelihood of being retained in care (risk ratio [RR] = 1.14; 95% confidence interval (CI): 0.94, 1.38). However, referral to disclosure counseling was associated with a moderate increase in retention (RR = 1.37; 95% CI: 1.21, 1.55) and was not significantly modified by prior disclosure status (p = .3). Our results suggest that while self-disclosure may not significantly improve retention among patients receiving care at these Cameroon sites, counseling services may play an important role regardless of prior disclosure status.

The effects of fixed and removable orthodontic retainers: a systematic review

Directory of Open Access Journals (Sweden)

Dalya Al-Moghrabi

2016-07-01

Full Text Available Abstract Objective In the view of the widespread acceptance of indefinite retention, it is important to determine the effects of fixed and removable orthodontic retainers on periodontal health, survival and failure rates of retainers, cost-effectiveness, and impact of orthodontic retainers on patient-reported outcomes. Methods A comprehensive literature search was undertaken based on a defined electronic and gray literature search strategy (PROSPERO: CRD42015029169. The following databases were searched (up to October 2015; MEDLINE via OVID, PubMed, the Cochrane Central Register of Controlled Trials, LILACS, BBO, ClinicalTrials.gov, the National Research Register, and ProQuest Dissertation and Thesis database. Randomized and non-randomized controlled clinical trials, prospective cohort studies, and case series (minimum sample size of 20 with minimum follow-up periods of 6 months reporting periodontal health, survival and failure rates of retainers, cost-effectiveness, and impact of orthodontic retainers on patient-reported outcomes were identified. The Cochrane Collaboration’s Risk of Bias tool and Newcastle-Ottawa Scale were used to assess the quality of included trials. Results Twenty-four studies were identified, 18 randomized controlled trials and 6 prospective cohort studies. Of these, only 16 were deemed to be of high quality. Meta-analysis was unfeasible due to considerable clinical heterogeneity and variations in outcome measures. The mean failure risk for mandibular stainless steel fixed retainers bonded from canine to canine was 0.29 (95 % confidence interval [CI] 0.26, 0.33 and for those bonded to canines only was 0.25 (95 % CI: 0.16, 0.33. A meta-regression suggested that failure of fixed stainless steel mandibular retainers was not directly related to the period elapsed since placement (P = 0.938. Conclusion Further well-designed prospective studies are needed to elucidate the benefits and potential harms associated with

Retention of Mastoidectomy Skills After Virtual Reality Simulation Training

DEFF Research Database (Denmark)

Andersen, Steven Arild Wuyts; Konge, Lars; Cayé-Thomasen, Per

2016-01-01

IMPORTANCE: The ultimate goal of surgical training is consolidated skills with a consistently high performance. However, surgical skills are heterogeneously retained and depend on a variety of factors, including the task, cognitive demands, and organization of practice. Virtual reality (VR......) simulation is increasingly being used in surgical skills training, including temporal bone surgery, but there is a gap in knowledge on the retention of mastoidectomy skills after VR simulation training. OBJECTIVES: To determine the retention of mastoidectomy skills after VR simulation training...... with distributed and massed practice and to investigate participants' cognitive load during retention procedures. DESIGN, SETTING, AND PARTICIPANTS: A prospective 3-month follow-up study of a VR simulation trial was conducted from February 6 to September 19, 2014, at an academic teaching hospital among 36 medical...

Uranium retention in aqueous hydroxyapatite suspensions

International Nuclear Information System (INIS)

Leyva, Ana G.; Marrero, Julieta G.; Perez Arisnabarreta, Sebastian A.; Di Nanno, Maria P.; Smichowski, Patricia N.

2000-01-01

Batch equilibration were performed to study the ability of synthetic hydroxyapatite (HAP)[Ca 10 (PO 4 ) 6 (OH) 2 ] to immobilize uranium. Different parameters affecting U uptake were evaluated. These studies showed that U was quantitatively retained in a wide range of pHs in the first 15 minutes. These experiments were performed at different U concentrations, between 1 to 100 μg/g and in all cases U uptake did not depend on U concentration. The high retention of U in HAP could be explained by the high specific surface area of the synthesized starting material. The solid phase was characterised by energy dispersive X-ray (EDAX) analysis before and after U retention. Effluents were treated using the proposed method and recovery studies were in all cases better than 90%. (author)

Stability of orthodontic treatment outcome in relation to retention status: An 8-year follow-up.

Science.gov (United States)

Steinnes, Jeanett; Johnsen, Gunn; Kerosuo, Heidi

2017-06-01

Our aim was to evaluate the stability of orthodontic treatment outcome and retention status 7 or more years after active treatment in relation to posttreatment or postretention time, type of retention appliance, and duration of retainer use. The subjects were former patients who completed orthodontic treatment with fixed appliances from 2000 to 2007. The pretreatment eligibility criteria were anterior crowding of 4 mm or more in the maxilla or the mandible and Angle Class I or Class II sagittal molar relationship. Acceptable pretreatment and posttreatment dental casts were required. A total of 67 patients participated, 24 men and 43 women, with a mean age of 24.7 years (range, 20.0-50.0 years). All participants had a follow-up clinical examination, which included impressions for follow-up casts, and each completed a questionnaire. Data were obtained from pretreatment, posttreatment, and follow-up (T2) casts as well as from the patients' dental records. Treatment stability was evaluated with the peer assessment rating (PAR) index and Little's irregularity index. The participation rate was 64%. The average posttreatment time was 8.5 years (range, 7.0-11.0). All participants had received a retainer in the mandible, maxilla, or both after active treatment. At T2, the PAR score showed a mean relapse of 14%. The majority (78%) of participants still had a fixed retainer at T2 (retainer group), and 22% had been out of retention for at least 1 year (postretention group). The relapse according to the PAR did not differ significantly between participants with and without a retainer at T2. From posttreatment to T2, the irregularity of the mandibular incisors increased almost 3 times more in participants with no retainer in the mandible compared with those with an intact retainer at T2 (P = 0.001). In the maxilla, no corresponding difference was found. Our results suggest that occlusal relapse can be expected after active orthodontic treatment irrespective of long

Fuel hydrogen retention of tungsten and the reduction by inert gas glow discharges

Energy Technology Data Exchange (ETDEWEB)

Hino, T., E-mail: tomhino@qe.eng.hokudai.ac.jp [Laboratory of Plasma Physics and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Yamauchi, Y.; Kimura, Y. [Laboratory of Plasma Physics and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Nishimura, K. [National Institute for Fusion Science, Toki-shi, Gifu-ken 509-5292 (Japan); Ueda, Y. [Graduate School of Engineering, Osaka University, Suita-shi 565-0872 (Japan)

2012-08-15

Highlights: Black-Right-Pointing-Pointer The performances of inert gas glow discharges for reduction of fuel hydrogen retention in tungsten were systematically investigated. Black-Right-Pointing-Pointer For the tungsten with rough surface structure, the reduction of fuel hydrogen retention by inert gas discharges is quite small. Black-Right-Pointing-Pointer The deuterium glow discharge is quite useful to reduce the tritium retention in plasma facing walls in fusion reactor. Black-Right-Pointing-Pointer The wall baking with temperature higher than 700-800 K is also useful to reduce the tritium retention in plasma facing walls. - Abstract: Polycrystalline tungsten was exposed to deuterium glow discharge followed by He, Ne or Ar glow discharge. The amount of retained deuterium in the tungsten was measured using residual gas analysis. The amount of desorbed deuterium during the inert gas glow discharge was also measured. The amount of retained deuterium was 2-3 times larger compared with a case of stainless steel. The ratios of desorbed amount of deuterium by He, Ne and Ar glow discharges were 4.6, 3.1 and 2.9%, respectively. These values were one order of magnitude smaller compared with the case of stainless steel. The inert gas glow discharge is not suitable to reduce the fuel hydrogen retention for tungsten walls. However, the wall baking with a temperature higher than 700 K is suitable to reduce the fuel hydrogen retention. It is also shown that the use of deuterium glow discharge is effective to reduce the in-vessel tritium inventory in fusion reactors through the hydrogen isotope exchange.

Factors influencing intentions to stay and retention of nurse managers: a systematic review.

Science.gov (United States)

Brown, Pamela; Fraser, Kimberly; Wong, Carol A; Muise, Melanie; Cummings, Greta

2013-04-01

This systematic review aimed to explore factors known to influence intentions to stay and retention of nurse managers in their current position. Retaining staff nurses and recruiting nurses to management positions are well documented; however, there is sparse research examining factors that influence retention of nurse managers. Thirteen studies were identified through a systematic search of the literature. Eligibility criteria included both qualitative and quantitative studies that examined factors related to nurse manager intentions to stay and retention. Quality assessments, data extraction and analysis were completed on all studies included. Twenty-one factors were categorized into three major categories: organizational, role and personal. Job satisfaction, organizational commitment, organizational culture and values, feelings of being valued and lack of time to complete tasks leading to work/life imbalance, were prominent across all categories. These findings suggest that intentions to stay and retention of nurse managers are multifactoral. However, lack of robust literature highlights the need for further research to develop strategies to retain nurse managers. ImplICATIONS FOR NURSE MANAGEMENT: Health-care organizations and senior decision-makers should feel a responsibility to support front-line managers in relation to workload and span of control, and in understanding work/life balance issues faced by managers. © 2012 Blackwell Publishing Ltd.

Retention of plutonium in the beagle after gastrointestinal absorption

International Nuclear Information System (INIS)

Toohey, R.E.; Bhattacharyya, M.H.; Oldham, R.D.; Larsen, R.P.; Moretti, E.S.

1985-01-01

A 0.01 M bicarbonate solution containing 130 nCi (approx. 5 kBq) of 237 Pu (90% hexavalent, 93% ultrafilterable) was administered via gelatin capsule to six adult male beagles following a 21-hr fast. The dogs were sacrificed after 5-6 weeks and the percentage of the administered plutonium retained in the liver plus skeleton and its distribution within the skeleton were determined. The mean amount retained in these tissues was (0.063 +- 0.006)% of the administered dose. The mean amounts of plutonium in the liver and the skeleton were approximately equal, and the distribution within the skeleton was similar to that observed by other workers following either intravenous injection or inhalation. The value for plutonium retention by the dog is about a factor of three less than the values the authors have reported for rodents. It is a factor of 7 greater than the product of the values for gastrointestinal absorption (f 1 ) and fractional retention (f 2 ) recommended by the ICRP for man

Welfare and Work: Job-Retention Outcomes of Federal Welfare-to-Work Employees.

Science.gov (United States)

Gooden, Susan Tinsley; Bailey, Margo

2001-01-01

Comparison of differences in job-retention outcomes for 1,777 welfare-to-work employees and 16,723 other employees in federal agencies reveals that welfare-to-work employees have greater odds of retaining their jobs. (Contains 32 references.) (JOW)

Retention of Differential and Integral Calculus: A Case Study of a University Student in Physical Chemistry

Science.gov (United States)

Jukic Matic, Ljerka; Dahl, Bettina

2014-01-01

This paper reports a study on retention of differential and integral calculus concepts of a second-year student of physical chemistry at a Danish university. The focus was on what knowledge the student retained 14 months after the course and on what effect beliefs about mathematics had on the retention. We argue that if a student can quickly…

Comparative evaluation of salivary bisphenol A levels in patients wearing vacuum-formed and Hawley retainers: An in-vivo study.

Science.gov (United States)

Raghavan, Akila Srinivasan; Pottipalli Sathyanarayana, Haritha; Kailasam, Vignesh; Padmanabhan, Sridevi

2017-03-01

The aims of the study were to evaluate and compare the bisphenol A (BPA) levels in saliva in patients using vacuum-formed retainers or Hawley retainers. Forty-five patients who had completed their fixed orthodontic treatment and were entering the retention phase were randomly allocated into 1 of 3 groups: vacuum-formed retainer, Hawley retainer fabricated by heat cure, and Hawley retainer fabricated by chemical cure. Saliva samples were collected immediately before placement, within 1 hour after placement, 1 week and 1 month after placement. Statistical analyses were performed by using 2-way analysis of variance and post-hoc multiple-comparisons Tukey HSD tests. Statistically significant BPA levels in saliva were found for all groups (P ≤0.05). The highest levels were noted in the vacuum-formed retainer group, followed by Hawley retainers fabricated by chemical cure; the lowest levels were found with Hawley retainers fabricated by heat cure. With many options available for removable retainers, clinicians should consider the BPA release from these retainers; a Hawley retainer fabricated by heat cure is a favorable choice. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

76 FR 53667 - Establishing a One-Year Retention Period for Patent-Related Papers That Have Been Scanned Into...

Science.gov (United States)

2011-08-29

... replace the USPTO's past practice of indefinitely retaining the papers, which has been rendered... costs. The USPTO's past practice of indefinitely retaining the boxes of papers that it scans into IFW or...-Year Retention Period for Patent-Related Papers That Have Been Scanned Into the Image File Wrapper...

Mobile health for early retention in HIV care: a qualitative study in ...

African Journals Online (AJOL)

Mobile health for early retention in HIV care: a qualitative study in Kenya (WelTel Retain). Kirsten Smillie, Natasha Van Borek, Mia L van der Kop, Abigael Lukhwaro, Neville Li, Sarah Karanja, Anik R Patel, David Ojakaa, Richard T Lester ...

One-Piece Implant-Retained Mandibular Overdentures By Pre-Fabricated Titanium Telescopic Attachments and Frictional Varnish: A Two-Year Prospective Study.

Science.gov (United States)

Nik, Shahram Namjoy; Nejatian, Touraj

2016-12-01

Clinical efficiency of one-piece screw-type implants with telescopic were attachments evaluated in this study. Twenty-four patients received a mandibular implant-supported overdenture and maxillary complete denture. Ninety-six one-piece implants were inserted in the inter-foraminal area. Implants were immediately loaded with an implant-retained overdenture and telescopic attachments which had frictional retention elements. There was 0.25±0.24 mm, 0.32±0.25 mm, 0.43±0.30 mm, 0.61±0.30 mm and of bone resorption after 3, 6, 12 and 24 months, respectively. The need to activate the frictional retention was the most common complication. Treatment outcomes for prefabricated telescopic retained overdentures on one-piece implants are similar to that obtained in cases of delayed loading. Copyright© 2016 Dennis Barber Ltd.

The impact of recognition on retention of good talent in the workforce

Directory of Open Access Journals (Sweden)

Nonhlanhla Mngomezulu

2015-10-01

Full Text Available Retention of talented workforce is the most crucial issue business sectors are faced with today as a result of brain drain.Talent has become the driving force for business success. Most employees leave due to lack of professional challenges, having received little or no recognition, and the absence of career growth and development. The purpose of this study is to determine the impact recognition has on retention of talented workforce in the workplace. A total of 70 questionnaires were distributed to employees in different job categories. The study revealed that management can apply numerous approaches to retain good talent. Moreover, it is vital for managers to bear in mind that these approaches might have dissimilar effects on different individuals. This study also answered some of the most critical issues the business sector is faced with, such as employee retention due to the shortage of skilled labour and failure to recognize good work done. The findings reflect that reward, passion, recognition, motivation, and effective talent management are some of the factors business leaders have to address in order to minimize voluntary turnover and retain good talent in the workplace

How nuclear power began

International Nuclear Information System (INIS)

Gowing, M.

1987-01-01

Many of the features of the story of nuclear power, both in nuclear weapons and nuclear power stations, derive from their timing. Usually, in the history of science the precise timing of discovery does not make much difference, but in the case of nuclear fission there was the coincidence that crucial discoveries were made and openly published in the same year, 1939, as the outbreak of the Second World War. It is these events of the 1930s and the early post-war era that are mainly discussed. However, the story began a lot earlier and even in the early 1900s the potential power within the atom had been foreseen by Soddy and Rutherford. In the 1930s Enrico Fermi and his team saw the technological importance of their discoveries and took out a patent on their process to produce artificial radioactivity from slow neutron beams. The need for secrecy because of the war, and the personal trusts and mistrusts run through the story of nuclear power. (UK)

Role of male partner involvement in ART retention and adherence in Malawi's Option B+ program.

Science.gov (United States)

Wesevich, Austin; Mtande, Tiwonge; Saidi, Friday; Cromwell, Elizabeth; Tweya, Hannock; Hosseinipour, Mina C; Hoffman, Irving; Miller, William C; Rosenberg, Nora E

2017-11-01

Malawi's Option B+ program provides all HIV-infected pregnant women free lifelong antiretroviral therapy (ART), but challenges remain regarding retention and ART adherence, potentially due to male partner barriers. We explored relationships between male partner involvement and Option B+ retention and adherence. In 2014, a randomized controlled trial in Malawi compared male recruitment strategies for couple HIV testing and counseling (cHTC) at an antenatal clinic. This secondary analysis was conducted among the entire cohort (N = 200) of women, irrespective of randomization status. We assessed whether cHTC attendance, early disclosure of HIV-positive status, and partner ART reminders were associated with retention and adherence at one month after starting treatment. Retention was defined as attending HIV clinic follow-up within one day of running out of pills. Adherence was defined as taking ≥95% of ARTs by pill count. We used binomial regression to calculate adjusted risk ratios (aRR) and 95% confidence intervals (CI). Median female age was 26 years. Most women (79%) were retained; of these, 68% were adherent. Receiving cHTC was associated with improved retention (aRR 1.33, 95% CI 1.12, 1.59). Receiving male partner ART reminders was weakly associated with retention (aRR 1.16, 95% CI 0.96, 1.39). Disclosure within one day was not associated with retention (aRR 1.08, 95% CI: 0.91, 1.28). Among those who were retained, these three behaviors were not associated with improved 95% adherence. CHTC could play an important role in improving Option B+ retention. Increasing cHTC participation and enhancing adherence-related messages within cHTC are important.

Retaining clients in an outcome monitoring evaluation study: HIV prevention efforts in community settings.

Science.gov (United States)

Smith, Bryce D; Kalayil, Elizabeth J; Patel-Larson, Alpa; Chen, Brenda; Vaughan, Marla

2012-02-01

The Centers for Disease Control and Prevention (CDC), Division of HIV/AIDS Prevention (DHAP) conducted outcome monitoring studies on evidence-based interventions (EBIs) provided by CDC-funded community-based organizations (CBOs). Critical to the success of outcome monitoring was the ability of CBOs to recruit and retain clients in evaluation studies. Two EBIs, Video Opportunities for Innovative Condom Education and Safer Sex (VOICES/VOCES) and Healthy Relationships, were evaluated using repeated measure studies, which require robust follow-up retention rates to increase the validity and usefulness of the findings. The retention rates were high for both VOICES/VOCES CBOs (95.8% at 30 days and 91.1% at 120 days), and Healthy Relationships CBOs (89.5% at 90 days and 83.5% at 180 days). This paper presents an overview of the retention of clients, challenges to follow-up, and strategies developed by CBOs to achieve high retention rates. These strategies and rates are discussed within the context of the CBOs' target populations and communities. Published by Elsevier Ltd.

Coarse Particulate Organic Matter: Storage, Transport, and Retention

Energy Technology Data Exchange (ETDEWEB)

Tiegs, Scott [Oakland University, Rochester, MI; Lamberti, Gary A. [University of Notre Dame, IN; Entrekin, Sally A. [University of Central Arkansas; Griffiths, Natalie A. [ORNL

2017-08-01

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

Coarse Particulate Organic Matter: Storage, Transport, and Retention

Energy Technology Data Exchange (ETDEWEB)

Tiegs, Scott [Oakland University, Rochester, MI; Lamberti, Gary A. [University of Notre Dame, IN; Entrekin, Sally A. [University of Central Arkansas; Griffiths, Natalie A. [ORNL

2017-06-01

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

Retention performance of green roofs in representative climates worldwide

Science.gov (United States)

Viola, F.; Hellies, M.; Deidda, R.

2017-10-01

The ongoing process of global urbanization contributes to an increase in stormwater runoff from impervious surfaces, threatening also water quality. Green roofs have been proved to be innovative stormwater management measures to partially restore natural states, enhancing interception, infiltration and evapotranspiration fluxes. The amount of water that is retained within green roofs depends not only on their depth, but also on the climate, which drives the stochastic soil moisture dynamic. In this context, a simple tool for assessing performance of green roofs worldwide in terms of retained water is still missing and highly desirable for practical assessments. The aim of this work is to explore retention performance of green roofs as a function of their depth and in different climate regimes. Two soil depths are investigated, one representing the intensive configuration and another representing the extensive one. The role of the climate in driving water retention has been represented by rainfall and potential evapotranspiration dynamics. A simple conceptual weather generator has been implemented and used for stochastic simulation of daily rainfall and potential evapotranspiration. Stochastic forcing is used as an input of a simple conceptual hydrological model for estimating long-term water partitioning between rainfall, runoff and actual evapotranspiration. Coupling the stochastic weather generator with the conceptual hydrological model, we assessed the amount of rainfall diverted into evapotranspiration for different combinations of annual rainfall and potential evapotranspiration in five representative climatic regimes. Results quantified the capabilities of green roofs in retaining rainfall and consequently in reducing discharges into sewer systems at an annual time scale. The role of substrate depth has been recognized to be crucial in determining green roofs retention performance, which in general increase from extensive to intensive settings. Looking at the

The Receipt of Special Education Services Following Elementary School Grade Retention

Science.gov (United States)

Silverstein, Michael; Guppy, Nicole; Young, Robin; Augustyn, Marilyn

2009-01-01

Objective To estimate the proportion of children who receive an Individualized Education Program (IEP) following grade retention in elementary school. Design/setting Descriptive analysis of a nationally representative, longitudinal cohort. Participants Children retained in K/1 and 3rd grade for presumed academic reasons, followed through fifth grade. Outcome measure Presence or absence of an IEP. Results 300 children retained for presumed academic reasons in K/1, and 80 in 3rd grade were included in the study. Of the K/1 retainees, 68% never received an IEP over the subsequent four to five years; of the 3rd grade retainees, 73% never received an IEP. K/1 retainees in the highest SES quintile and suburban K/1 retainees were less likely to receive an IEP than retained children in all other SES quintiles (aOR 0.17; 95% CI 0.05-0.62) and in rural communities (aOR 0.16; 95% CI 0.06-0.44), respectively. Among K/1 retainees with persistent low academic achievement in reading and math (as assessed by standardized testing), 37% and 28%, respectively, never received an IEP. Conclusions The majority of children retained in K/1 or 3rd grade for academic reasons, including a many of those who demonstrate sustained academic difficulties, never receive an IEP during elementary school. Further studies are important to elucidate whether retained elementary school children are being denied their rights to special education services. In the meantime, early grade retention may provide an opportunity for pediatricians to help families advocate for appropriate special education evaluations for children experiencing school difficulties. PMID:19487611

A dynamic processes study of PM retention by trees under different wind conditions.

Science.gov (United States)

Xie, Changkun; Kan, Liyan; Guo, Jiankang; Jin, Sijia; Li, Zhigang; Chen, Dan; Li, Xin; Che, Shengquan

2018-02-01

Particulate matter (PM) is one of the most serious environmental problems, exacerbating respiratory and vascular illnesses. Plants have the ability to reduce non-point source PM pollution through retention on leaves and branches. Studies of the dynamic processes of PM retention by plants and the mechanisms influencing this process will help to improve the efficiency of urban greening for PM reduction. We examined dynamic processes of PM retention and the major factors influencing PM retention by six trees with different branch structure characteristics in wind tunnel experiments at three different wind speeds. The results showed that the changes of PM numbers retained by plant leaves over time were complex dynamic processes for which maximum values could exceed minimum values by over 10 times. The average value of PM measured in multiple periods and situations can be considered a reliable indicator of the ability of the plant to retain PM. The dynamic processes were similar for PM 10 and PM 2.5 . They could be clustered into three groups simulated by continually-rising, inverse U-shaped, and U-shaped polynomial functions, respectively. The processes were the synthetic effect of characteristics such as species, wind speed, period of exposure and their interactions. Continually-rising functions always explained PM retention in species with extremely complex branch structure. Inverse U-shaped processes explained PM retention in species with relatively simple branch structure and gentle wind. The U-shaped processes mainly explained PM retention at high wind speeds and in species with a relatively simple crown. These results indicate that using plants with complex crowns in urban greening and decreasing wind speed in plant communities increases the chance of continually-rising or inverse U-shaped relationships, which have a positive effect in reducing PM pollution. Copyright © 2017 Elsevier Ltd. All rights reserved.

Retention of Cardiopulmonary Resuscitation Skills in Nigerian Secondary School Students

Science.gov (United States)

Onyeaso, Adedamola Olutoyin

2016-01-01

Background/Objective: For effective bystander cardiopulmonary resuscitation (CPR), retention of CPR skills after the training is central. The objective of this study was to find out how much of the CPR skills a group of Nigerian secondary school students would retain six weeks after their first exposure to the conventional CPR training. Materials…

Design principles for engaging and retaining virtual citizen scientists.

Science.gov (United States)

Wald, Dara M; Longo, Justin; Dobell, A R

2016-06-01

Citizen science initiatives encourage volunteer participants to collect and interpret data and contribute to formal scientific projects. The growth of virtual citizen science (VCS), facilitated through websites and mobile applications since the mid-2000s, has been driven by a combination of software innovations and mobile technologies, growing scientific data flows without commensurate increases in resources to handle them, and the desire of internet-connected participants to contribute to collective outputs. However, the increasing availability of internet-based activities requires individual VCS projects to compete for the attention of volunteers and promote their long-term retention. We examined program and platform design principles that might allow VCS initiatives to compete more effectively for volunteers, increase productivity of project participants, and retain contributors over time. We surveyed key personnel engaged in managing a sample of VCS projects to identify the principles and practices they pursued for these purposes and led a team in a heuristic evaluation of volunteer engagement, website or application usability, and participant retention. We received 40 completed survey responses (33% response rate) and completed a heuristic evaluation of 20 VCS program sites. The majority of the VCS programs focused on scientific outcomes, whereas the educational and social benefits of program participation, variables that are consistently ranked as important for volunteer engagement and retention, were incidental. Evaluators indicated usability, across most of the VCS program sites, was higher and less variable than the ratings for participant engagement and retention. In the context of growing competition for the attention of internet volunteers, increased attention to the motivations of virtual citizen scientists may help VCS programs sustain the necessary engagement and retention of their volunteers. © 2016 Society for Conservation Biology.

The impact of cooking and delivery modes of thymol and carvacrol on retention and bioaccessibility in starchy foods.

Science.gov (United States)

Aravena, Gabriela; García, Olga; Muñoz, Ociel; Pérez-Correa, José R; Parada, Javier

2016-04-01

Oregano and thyme possess beneficial properties for human health, mainly attributable to monoterpenes such as thymol and carvacrol. The main objective of this research was to assess, on starchy food, the impact of cooking (boiling and baking) and delivery (ground leaves and essential oil) modes on retention and bioaccessibility of thymol and carvacrol. Retention was assessed after cooking, while bioaccessibility was estimated in cooked samples using an in vitro digestion model. Our results indicate that bioaccessibility was weakly dependent on cooking and delivery modes (27-33%). Boil cooking presented 20% more retention than baking for both compounds. When essential oil was added to the food matrix, thymol was retained almost 25% more when compared with ground leaves' addition. Conversely, carvacrol was retained 39% more when ground leaves were added. Copyright © 2015 Elsevier Ltd. All rights reserved.

Retention of krypton on polymethyl methacrylate

International Nuclear Information System (INIS)

Ciric, M.M.; Cvjeticanin, N.M.; Radak, B.B.

1975-01-01

Retention of krypton on polymethyl methacrylate was studied as a function of kryptonation pressure (P), temperature (T) and time (t). It was found that the dependence of the retained quantity on P, T, and t is in accordance with the diffusion theory. The optimum results (i.e., the maximum retained quantity and the best stability of the kryptonate) were obtained at elevated kryptonation temperatures (200 0 C). The diffusion coefficients of krypton in polymethyl methacrylate, determined from the dekryptonation process, vary from 1 x 10 -10 cm 2 /s to 0.2 x 10 -10 cm 2 /s for samples kryptonated at 20 0 C and 200 0 C respectively. The results have been discussed from the viewpoint of radiation and thermal stability of kryptonated polymethyl methacrylate. Inadequate radiation stability could be the main obstacle for practical purposes. (U.S.)

Poor retention does not have to be the rule: retention of volunteer community health workers in Uganda.

Science.gov (United States)

Ludwick, Teralynn; Brenner, Jennifer L; Kyomuhangi, Teddy; Wotton, Kathryn A; Kabakyenga, Jerome Kahuma

2014-05-01

Globally, health worker shortages continue to plague developing countries. Community health workers are increasingly being promoted to extend primary health care to underserved populations. Since 2004, Healthy Child Uganda (HCU) has trained volunteer community health workers in child health promotion in rural southwest Uganda. This study analyses the retention and motivation of volunteer community health workers trained by HCU. It presents retention rates over a 5-year period and provides insight into volunteer motivation. The findings are based on a 2010 retrospective review of the community health worker registry and the results of a survey on selection and motivation. The survey was comprised of qualitative and quantitative questions and verbally administered to a convenience sample of project participants. Between February 2004 and July 2009, HCU trained 404 community health workers (69% female) in 175 villages. Volunteers had an average age of 36.7 years, 4.9 children and some primary school education. Ninety-six per cent of volunteer community health workers were retained after 1 year (389/404), 91% after 2 years (386/404) and 86% after 5 years (101/117). Of the 54 'dropouts', main reasons cited for discontinuation included 'too busy' (12), moved (11), business/employment (8), death (6) and separation/divorce (6). Of 58 questionnaire respondents, most (87%) reported having been selected at an inclusive community meeting. Pair-wise ranking was used to assess the importance of seven 'motivational factors' among respondents. Those highest ranked were 'improved child health', 'education/training' and 'being asked for advice/assistance by peers', while the modest 'transport allowance' ranked lowest. Our findings suggest that in our rural, African setting, volunteer community health workers can be retained over the medium term. Community health worker programmes should invest in community involvement in selection, quality training, supportive supervision and

Psychological determinants of job retention in multiple sclerosis.

Science.gov (United States)

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

2018-01-01

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

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

International Nuclear Information System (INIS)

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

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

Energy Technology Data Exchange (ETDEWEB)

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

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.

Plastic debris retention and exportation by a mangrove forest patch.

Science.gov (United States)

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). Copyright © 2013 Elsevier Ltd. All rights reserved.

Effect of an interactive text-messaging service on patient retention during the first year of HIV care in Kenya (WelTel Retain): an open-label, randomised parallel-group study.

Science.gov (United States)

van der Kop, Mia Liisa; Muhula, Samuel; Nagide, Patrick I; Thabane, Lehana; Gelmon, Lawrence; Awiti, Patricia Opondo; Abunah, Bonface; Kyomuhangi, Lennie Bazira; Budd, Matthew A; Marra, Carlo; Patel, Anik; Karanja, Sarah; Ojakaa, David I; Mills, Edward J; Ekström, Anna Mia; Lester, Richard Todd

2018-03-01

Retention of patients in HIV care is crucial to ensure timely treatment initiation, viral suppression, and to avert AIDS-related deaths. We did a randomised trial to determine whether a text-messaging intervention improved retention during the first year of HIV care. This unmasked, randomised parallel-group study was done at two clinics in informal settlements in Nairobi, Kenya. Eligible participants were aged 18 years or older, HIV-positive, had their own mobile phone or access to one, and were able to use simple text messaging (or have somebody who could text message on their behalf). Participants were randomly assigned (1:1), with random block sizes of 2, 4, and 6, to the intervention or control group. Participants in the intervention group received a weekly text message from the automated WelTel service for 1 year and were asked to respond within 48 h. Participants in the control group did not receive text messages. Participants in both groups received usual care, which comprised psychosocial support and counselling; patient education; CD4 cell count; treatment; screening for tuberculosis, opportunistic infections, and sexually transmitted infections; prevention of mother-to-child transmission and family planning services; and up to two telephone calls for missed appointments. The primary outcome was retention in care at 12 months (ie, clinic attendance 10-14 months after the first visit). Participants who did not attend this 12-month appointment were traced, and we considered as retained those who were confirmed to be active in care elsewhere. The data analyst and clinic staff were masked to the group assignment, whereas participants and research nurses were not. We analysed the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01630304. Between April 4, 2013, and June 4, 2015, we screened 1068 individuals, of whom 700 were recruited. 349 people were allocated to the intervention group and 351 to the control group

Retention of Mastoidectomy Skills After Virtual Reality Simulation Training.

Science.gov (United States)

Andersen, Steven Arild Wuyts; Konge, Lars; Cayé-Thomasen, Per; Sørensen, Mads Sølvsten

2016-07-01

The ultimate goal of surgical training is consolidated skills with a consistently high performance. However, surgical skills are heterogeneously retained and depend on a variety of factors, including the task, cognitive demands, and organization of practice. Virtual reality (VR) simulation is increasingly being used in surgical skills training, including temporal bone surgery, but there is a gap in knowledge on the retention of mastoidectomy skills after VR simulation training. To determine the retention of mastoidectomy skills after VR simulation training with distributed and massed practice and to investigate participants' cognitive load during retention procedures. A prospective 3-month follow-up study of a VR simulation trial was conducted from February 6 to September 19, 2014, at an academic teaching hospital among 36 medical students: 19 from a cohort trained with distributed practice and 17 from a cohort trained with massed practice. Participants performed 2 virtual mastoidectomies in a VR simulator a mean of 3.2 months (range, 2.4-5.0 months) after completing initial training with 12 repeated procedures. Practice blocks were spaced apart in time (distributed), or all procedures were performed in 1 day (massed). Performance of the virtual mastoidectomy as assessed by 2 masked senior otologists using a modified Welling scale, as well as cognitive load as estimated by reaction time to perform a secondary task. Among 36 participants, mastoidectomy final-product skills were largely retained at 3 months (mean change in score, 0.1 points; P = .89) regardless of practice schedule, but the group trained with massed practice took more time to complete the task. The performance of the massed practice group increased significantly from the first to the second retention procedure (mean change, 1.8 points; P = .001), reflecting that skills were less consolidated. For both groups, increases in reaction times in the secondary task (distributed practice group: mean

Preoperative Surgical Discussion and Information Retention by Patients.

Science.gov (United States)

Feiner, David E; Rayan, Ghazi M

2016-10-01

To assess how much information communicated to patients is understood and retained after preoperative discussion of upper extremity procedures. A prospective study was designed by recruiting patients prior to undergoing upper extremity surgical procedures after a detailed discussion of their operative technique, postoperative care and treatment outcomes. Patients were given the same 20-item questionnaire to fill out twice, at two pre operative visits. An independent evaluator filled out a third questionnaire as a control. Various discussion points of the survey were compared among the 3 questionnaires and retained information and perceived comprehension were evaluated. The average patients' age was 50.3 (27-75) years The average time between the two surveys preoperative 1 and preoperative 2 was 40.7 (7-75) days,. The average patient had approximately 2 years of college or an associate's degree. Patients initially retained 73% (52-90%) of discussion points presented during preoperative 1 and 61% (36-85%) of the information at preoperative 2 p = .002. 50% of patients felt they understood 100% of the discussion, this dropped to only 10% at their preoperative 2 visit. 15% of our patients did not know what type of anesthesia they were having at preoperative 2. A communication barrier between patients and physicians exists when patients are informed about their preoperative surgical discussion. The retention of information presented is worsened with elapsing time from the initial preoperative discussion to the second preoperative visit immediately prior to surgery. Methods to enhance patients' retention of information prior to surgery must be sought and implemented which will improve patients' treatment outcome.

Retention of seed trees fails to lifeboat ectomycorrhizal fungal diversity in harvested Scots pine forests.

Science.gov (United States)

Varenius, Kerstin; Lindahl, Björn D; Dahlberg, Anders

2017-09-01

Fennoscandian forestry has in the past decades changed from natural regeneration of forests towards replantation of clear-cuts, which negatively impacts ectomycorrhizal fungal (EMF) diversity. Retention of trees during harvesting enables EMF survival, and we therefore expected EMF communities to be more similar to those in old natural stands after forest regeneration using seed trees compared to full clear-cutting and replanting. We sequenced fungal internal transcribed spacer 2 (ITS2) amplicons to assess EMF communities in 10- to 60-year-old Scots pine stands regenerated either using seed trees or through replanting of clear-cuts with old natural stands as reference. We also investigated local EMF communities around retained old trees. We found that retention of seed trees failed to mitigate the impact of harvesting on EMF community composition and diversity. With increasing stand age, EMF communities became increasingly similar to those in old natural stands and permanently retained trees maintained EMF locally. From our observations, we conclude that EMF communities, at least common species, post-harvest are more influenced by environmental filtering, resulting from environmental changes induced by harvest, than by the continuity of trees. These results suggest that retention of intact forest patches is a more efficient way to conserve EMF diversity than retaining dispersed single trees. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

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

Science.gov (United States)

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

2014-01-24

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

Influence of temperature and plasma composition on deuterium retention in refractory metals

International Nuclear Information System (INIS)

Alves, E.; Alves, L.C.; Barradas, N.P.; Mateus, R.; Carvalho, P.A.; Wright, G.M.

2010-01-01

Refractory materials are being considered potential candidates to build the first wall of the fusion reactor chamber. This work reports on the results of the study of tungsten and molybdenum metals exposed to high flux densities (∼10 24 D/m 2 s) and low temperature (T e ∼ 3 eV) deuterium plasmas in Pilot-PSI irradiation facility. The hydrogenic retention in poly-crystalline W and Mo targets was studied with 3 He nuclear reaction analyses (NRA). The NRA results clearly show a two-dimensional radial distribution of the deuterium with a minimum at the center and a maximum close to the edge. These distribution correlates well with the thermal profile of the sample surface, where a maximum of ∼1600 K was measured at the center decreasing to ∼1000 K in the edges. A maximum deuterium fluence retention of 5 x 10 15 D/cm 2 was measured. The values of the retained fractions ranging from 10 -5 to 10 -6 D retained /D incident were measured with thermal desorption spectroscopy (TDS) and compares well with IBA results. Moreover, the presence of C in the plasma and its co-deposition increases the D retention in the region where a C film is formed. Both NRA and TDS results show no clear dependence of retention on incident fluence suggesting the absence of plasma related traps in W under these conditions.

Retaining customers in a managed care market. Hospitals must understand the connection between patient satisfaction, loyalty, retention, and revenue.

Science.gov (United States)

Gemme, E M

1997-01-01

Traditionally, health care patients have been treated by health care professionals as people with needs rather than as customers with options. Although managed care has restricted patient choice, choice has not been eliminated. The premise of this article is that patients are primary health care consumers. Adopting such a premise and developing an active customer retention program can help health care organizations change their culture for the better, which may lead to higher customer retention levels and increased revenues. Customer retention programs based on service excellence that empower employees to provide excellent care can eventually lead to a larger market share for health care organizations trying to survive this era of intense competition.

Fission gas retention and axial expansion of irradiated metallic fuel

International Nuclear Information System (INIS)

Fenske, G.R.; Emerson, J.E.; Savoie, F.E.; Johanson, E.W.

1986-05-01

Out-of-reactor experiments utilizing direct electrical heating and infrared heating techniques were performed on irradiated metallic fuel. The results indicate accelerated expansion can occur during thermal transients and that the accelerated expansion is driven by retained fission gases. The results also demonstrate gas retention and, hence, expansion behavior is a function of axial position within the pin

MULTIPLE RETAINED TEETH IN MANDIBLE: A Case Report

Directory of Open Access Journals (Sweden)

Cvetan Cvetanov

2010-07-01

Full Text Available Purpose: The aim of this science report is to show a rare case of multiple impacted teeth at adult patient and our propose clinical approach.Materials and methods: The clinical case is showed from adult man /64-year old/ with multiple impacted teeth (6 impacted teeth in the anterior place on the mandible were not suggestive of any syndrome or metabolic disorder. The extraction of the impacted teeth was made on two stage with piezosurgery unit under local anaesthesia. For prevention of postsurgical complications, as a swelling and prevention of postsurgical resorbtion were used coneshapes from pressure xeno colagen. To base on clinical and radiological examination we will discuss the differential diagnosis and we will offer a clinical approach about decided the case.Result and Conclusion: The incidence of multiple retained teeth by literature research range from 10.9% to 40.4%, most frequently is the retention of the third molars. In the literature most rarely have clinical reports about multiple retained teeth which differ from third molars at adult patients. The rare clinical case we showed is very demonstrative and the medicative approach which we used gave excellent result.

Crust growth and gas retention in synthetic Hanford waste

International Nuclear Information System (INIS)

Bryan, S.A.; Pederson, L.R.; Scheele, R.D.

1992-03-01

The focus of the work described here is to examine the principal contributing factors leading to slurry growth and gas retention within waste from a particular high-level waste tanks on the Hanford Site. Laboratory studies of aged synthetic waste have shown that the waste retains gases in the form of bubble attachment to solid particles. This attachment phenomenon is related to the presence of organic constituents (HEDTA, EDTA, and citrate) added to the waste matrix. The mechanism for bubble attachment is related to the hydrophobic surface produced by the organic complexant. The formation of a stable gas bubble/solid interaction is believed to be responsible for crust flotation and gas retention in the synthetic waste used here

Hydrogen retention properties of lithium film

International Nuclear Information System (INIS)

Kanaya, Koh; Yamauchi, Yuji; Hirohata, Yuko; Hino, Tomoaki; Mori, Kintaro

1998-01-01

Hydrogen retention properties of Li films and lithium oxide-lithium hydroxide (Li 2 O-LiOH) mixed films were investigated by two methods, hydrogen ion irradiation and hydrogen glow discharge. In a case of the hydrogen ion irradiation, thermal desorption spectrum of hydrogen retained in Li 2 O-LiOH film had two desorption peaks at around 470 K and 570 K. The ratio between retained hydrogen and Li atom was about 0.7. In a case of the hydrogen glow discharge, the hydrogen was also gettered in Li film during the discharge. The ratio of H/Li was almost 0.9. Most of gettered hydrogen desorbed by a baking with a temperature of 370 K. On the contrary, when the Li film exposed to the atmosphere was irradiated by the hydrogen plasma, the desorption of H 2 O was observed in addition to the adsorption of H 2 . (author)

Biofilm roughness determines Cryptosporidium parvum retention in environmental biofilms.

Science.gov (United States)

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

2012-06-01

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

The paper of the forests like retainers of carbon, an experience in the south of Mexico

International Nuclear Information System (INIS)

De Jong, Ben H; Soto Pinto, Lorena; Montoya Gomez, Guillermo; Nelson, Kristen; Taylor John; Tipper, Richard

1999-01-01

The forests play an important paper in the global cycle of the carbon. At the moment, the deforestation is responsible for approximately 1.8GtC (gigatons of carbon), 20% of the global annual emissions of carbonic gas caused by the human activity. However, it is calculated that the reforestation could retain from 50 to 150 GtC along next 50 years. Concepts related with the retention of carbon are discussed. The necessity is commented of carrying out the regulation of an international market in retention of carbon with the purpose of being able to maintain acceptable norms in the reforestation projects that are executed under this program

Particle retention during long discharges in Tore Supra and JET

International Nuclear Information System (INIS)

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

2003-01-01

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

Strategies to enhance participant recruitment and retention in research involving a community-based population.

Science.gov (United States)

McCullagh, Marjorie C; Sanon, Marie-Anne; Cohen, Michael A

2014-11-01

Challenges associated with recruiting and retaining community-based populations in research studies have been recognized yet remain of major concern for researchers. There is a need for exchange of recruitment and retention techniques that inform recruitment and retention strategies. Here, the authors discuss a variety of methods that were successful in exceeding target recruitment and retention goals in a randomized clinical trial of hearing protector use among farm operators. Recruitment and retention strategies were 1) based on a philosophy of mutually beneficial engagement in the research process, 2) culturally appropriate, 3) tailored to the unique needs of partnering agencies, and 4) developed and refined in a cyclical and iterative process. Sponsoring organizations are interested in cost-effective recruitment and retention strategies, particularly relating to culturally and ethnically diverse groups. These approaches may result in enhanced subject recruitment and retention, concomitant containment of study costs, and timely accomplishment of study aims. Copyright © 2014 Elsevier Inc. All rights reserved.

The immobilisation and retention of soluble arsenic, cadmium and zinc by biochar

International Nuclear Information System (INIS)

Beesley, Luke; Marmiroli, Marta

2011-01-01

Water-soluble inorganic pollutants may constitute an environmental toxicity problem if their movement through soils and potential transfer to plants or groundwater is not arrested. The capability of biochar to immobilise and retain arsenic (As), cadmium (Cd) and zinc (Zn) from a multi-element contaminated sediment-derived soil was explored by a column leaching experiment and scanning electron microanalysis (SEM/EDX). Sorption of Cd and Zn to biochar's surfaces assisted a 300 and 45-fold reduction in their leachate concentrations, respectively. Retention of both metals was not affected by considerable leaching of water-soluble carbon from biochar, and could not be reversed following subsequent leaching of the sorbant biochar with water at pH 5.5. Weakly water-soluble As was also retained on biochar's surface but leachate concentrations did not duly decline. It is concluded that biochar can rapidly reduce the mobility of selected contaminants in this polluted soil system, with especially encouraging results for Cd. - Research highlights: → The capability of biochar to immobilise and retain arsenic (As), cadmium (Cd) and zinc (Zn) from a multi-element contaminated sediment-derived soil was explored by a column leaching experiment and scanning electron microanalysis (SEM/EDX). We highlight the following results from this study: → Large surface area and surface sorption of Cd and Zn to biochar reduces the concentrations of these metals in leachates from a contaminated soil 300 and 45-fold respectively. → Metal retention was not reversible by continued leaching of the sorbant biochar. → Biochar increased leachate pH and water-soluble carbon but this did not appear to be detrimental to its effects and may aid retention of Cd. → Although some arsenic was sorbed to biochar, leachate concentrations were not duly reduced. → Developments in micro-analyses techniques will allow more detailed exploration of the encouraging results seen here with regards to interior

Enhancing knowledge retention in higher education: A case of the University of Zambia

Directory of Open Access Journals (Sweden)

Sitali Wamundila

2011-08-01

Full Text Available The purpose of this study was to investigate how knowledge retention may be enhanced at the University of Zambia (UNZA. A quantitative case study design employing a triangulation of data collection methods was used. Data were collected using interviews and questionnaires. Purposive sampling was used to determine participants for the interviews whilst stratified random sampling was employed to select the respondents for the questionnaire. The quantitative and qualitative data that was analysed using SPSS® indicates that UNZA lacked certain knowledge retention practices that might enable it to retain operational relevant knowledge. In view of the findings, the study recommends the adoption of a knowledge retention framework that could be embedded in UNZA’s knowledge management policy.

Green roofs'retention performances in different climates

Science.gov (United States)

Viola, Francesco; Hellies, Matteo; Deidda, Roberto

2017-04-01

The ongoing process of global urbanization contributes to increasing stormwater runoff from impervious surfaces, threatening also water quality. Green roofs have been proved to be an innovative stormwater management tool to partially restore natural state, enhancing interception, infiltration and evapotranspiration fluxes. The amount of water that is retained within green roofs depends mainly on both soil properties and climate. The evaluation of the retained water is not trivial since it depends on the stochastic soil moisture dynamics. The aim of this work is to explore performances of green roofs, in terms of water retention, as a function of their depth considering different climate regimes. The role of climate in driving water retention has been mainly represented by rainfall and potential evapotranspiration dynamics, which are simulated by a simple conceptual weather generator at daily time scale. The model is able to describe seasonal (in-phase and counter-phase) and stationary behaviors of climatic forcings. Model parameters have been estimated on more than 20,000 historical time series retrieved worldwide. Exemplifying cases are discussed for five different climate scenarios, changing the amplitude and/or the phase of daily mean rainfall and evapotranspiration forcings. The first scenario represents stationary climates, in two other cases the daily mean rainfall or the potential evapotranspiration evolve sinusoidally. In the latter two cases, we simulated the in-phase or in counter-phase conditions. Stochastic forcings have been then used as an input to a simple conceptual hydrological model which simulate soil moisture dynamics, evapotranspiration fluxes, runoff and leakage from soil pack at daily time scale. For several combinations of annual rainfall and potential evapotranspiration, the analysis allowed assessing green roofs' retaining capabilities, at annual time scale. Provided abacus allows a first approximation of possible hydrological benefits

Consideration of Cosmetic Surgery As Part of Women's Benefit-Provisioning Mate Retention Strategy.

Science.gov (United States)

Atari, Mohammad; Barbaro, Nicole; Sela, Yael; Shackelford, Todd K; Chegeni, Razieh

2017-01-01

Individuals perform mate retention behaviors to minimize the risk of partner infidelity and relationship dissolution. The current study investigates whether consideration of cosmetic surgery can be conceptualized as part of a broader strategy of mate retention for women, but not men. We hypothesized that women's consideration of cosmetic surgery would be positively associated with performance frequencies of Benefit-Provisioning and Cost-Inflicting mate retention behaviors. We recruited 203 individuals (54% women) in committed heterosexual relationships from Tehran, Iran. Results indicate a positive association between consideration of cosmetic surgery and Benefit-Provisioning mate retention behaviors for women, but not men. There was no association between consideration of cosmetic surgery and Cost-Inflicting mate retention behaviors. Women therefore may consider cosmetic surgery to improve their physical attractiveness as part of a Benefit-Provisioning strategy to retain a long-term mate. We discuss limitations of the study and highlight future directions for research from an evolutionary perspective.

Implications of invalidity of Data Retention Directive to telecom operators

Directory of Open Access Journals (Sweden)

Darja LONČAR DUŠANOVIĆ

2014-12-01

Full Text Available Obligation for telecom operators to retain traffic and location data for combating crime purposes had been controversial ever since the adoption of the Data Retention Directive in 2006 because of its inherent negative impact on the fundamental right to privacy and personal data protection. However, the awaited judgment of the CJEU in April this year, which declared the Directive invalid, did not so far resolve the ambiguity of the issue. Namely, having in mind that half a year later, some countries did not amend their national data retention legislations (yet to comply with the aforementioned CJEU judgment, telecom operators as addresses of this obligation are in uncertain legal situation which could be called “lose-lose” situation. Also, the emphasis from the question of proportionality between data privacy and public security is shifted to the question of existence of valid legal basis for data processing (retaining data and providing them to authorities in the new legal environment in which national and EU law are still not in compliance. In this paper the author examines the implications of the CJEU judgment to national EU legislation, telecom operators and data subjects, providing comparative analysis of national data retention legislation status in EU member states. The existence of valid legal basis for data processing is examined within EU law sources, including within proposed EU General Data Protection Regulation and opinions of the relevant data protection bodies (e.g. Article 29 Working Party.

Mathematics Teachers' Support and Retention: Using Maslow's Hierarchy to Understand Teachers' Needs

Science.gov (United States)

Fisher, Molly H.; Royster, David

2016-01-01

As part of a larger study, four mathematics teachers from diverse backgrounds and teaching situations report their ideas on teacher stress, mathematics teacher retention, and their feelings about the needs of mathematics teachers, as well as other information crucial to retaining quality teachers. The responses from the participants were used to…

Identifying, Monitoring, and Benchmarking Teacher Retention and Turnover: Guidelines for TIF Grantees

Science.gov (United States)

Finster, Matthew

2015-01-01

Having a well-qualified, effective teacher in every classroom is a cornerstone of current educational reforms. Clearly, retaining these effective teachers is critical to achieving this goal. This brief presents a strategic accountability approach to managing teacher talent retention and turnover. The brief begins with an overview of a strategic…

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

Science.gov (United States)

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.

Impact of Impaired Renal Function on Gadolinium Retention After Administration of Gadolinium-Based Contrast Agents in a Mouse Model.

Science.gov (United States)

Kartamihardja, A Adhipatria P; Nakajima, Takahito; Kameo, Satomi; Koyama, Hiroshi; Tsushima, Yoshito

2016-10-01

The aim of this study was to investigate the impact of impaired renal function on gadolinium (Gd) retention in various organs after Gd-based contrast agent injection. After local animal care and review committee approval, 23 normal mice and 26 with renal failure were divided into 4 treatment groups (Gd-DTPA-BMA, 5 mmol/kg; Gd-DOTA, 5 mmol/kg; GdCl3, 0.02 mmol/kg; and saline, 250 μL). Each agent was intravenously administered on weekdays for 4 weeks. Samples were collected on days 3 (short-term) and 45 (long-term) after the last injection. Gadolinium concentrations were quantified by inductively coupled plasma-mass spectrometry. Three mice with renal failure and 2 normal mice in the GdCl3 group and 1 mouse with renal failure in the Gd-DTPA-BMA group died. In the Gd-DTPA-BMA group, impaired renal function increased short-term Gd retention in the liver, bone, spleen, skin, and kidney (P DTPA-BMA showed higher Gd retention than Gd-DOTA. Although Gd retention in the Gd-DOTA group was generally low, impaired renal function increased only long-term hepatic Gd retention. Hepatic and splenic Gd retentions were significantly higher than other organs' Gd retention in the GdCl3 group (P DTPA-BMA administration, long-term Gd retention for Gd-based contrast agents was almost unaffected by renal function, suggesting that the chemical structures of retained Gd may not be consistent and some Gd is slowly eliminated after initially being retained.

Retention of Plasmodium falciparum ring-infected erythrocytes in the slow, open microcirculation of the human spleen.

Science.gov (United States)

Safeukui, Innocent; Correas, Jean-Michel; Brousse, Valentine; Hirt, Déborah; Deplaine, Guillaume; Mulé, Sébastien; Lesurtel, Mickael; Goasguen, Nicolas; Sauvanet, Alain; Couvelard, Anne; Kerneis, Sophie; Khun, Huot; Vigan-Womas, Inès; Ottone, Catherine; Molina, Thierry Jo; Tréluyer, Jean-Marc; Mercereau-Puijalon, Odile; Milon, Geneviève; David, Peter H; Buffet, Pierre A

2008-09-15

The current paradigm in Plasmodium falciparum malaria pathogenesis states that young, ring-infected erythrocytes (rings) circulate in peripheral blood and that mature stages are sequestered in the vasculature, avoiding clearance by the spleen. Through ex vivo perfusion of human spleens, we examined the interaction of this unique blood-filtering organ with P falciparum-infected erythrocytes. As predicted, mature stages were retained. However, more than 50% of rings were also retained and accumulated upstream from endothelial sinus wall slits of the open, slow red pulp microcirculation. Ten percent of rings were retained at each spleen passage, a rate matching the proportion of blood flowing through the slow circulatory compartment established in parallel using spleen contrast-enhanced ultrasonography in healthy volunteers. Rings displayed a mildly but significantly reduced elongation index, consistent with a retention process, due to their altered mechanical properties. This raises the new paradigm of a heterogeneous ring population, the less deformable subset being retained in the spleen, thereby reducing the parasite biomass that will sequester in vital organs, influencing the risk of severe complications, such as cerebral malaria or severe anemia. Cryptic ring retention uncovers a new role for the spleen in the control of parasite density, opening novel intervention opportunities.

Teacher Perceptions of Factors That Influence Job Satisfaction and Retention Decisions

Science.gov (United States)

Williams, Jill R.

2012-01-01

Retaining qualified teachers in America's schools is one of the nation's challenges in education. Current research revealed teacher turnover had risen to 16.9% nationally, which equates to 2.7 million teachers, including 2.1 million who left the profession before retirement. In order to make a positive change in teacher retention,…

Lithium concentration dependence of implanted helium retention in lithium silicates

Energy Technology Data Exchange (ETDEWEB)

Szocs, D.E., E-mail: szocsd@rmki.kfki.h [KFKI Research Institute for Particle and Nuclear Physics, H-1525 Budapest, P.O. Box 49 (Hungary); Szilagyi, E.; Bogdan, Cs.; Kotai, E. [KFKI Research Institute for Particle and Nuclear Physics, H-1525 Budapest, P.O. Box 49 (Hungary); Horvath, Z.E. [Research Institute for Technical Physics and Materials Science, H-1525 Budapest, P.O. Box 49 (Hungary)

2010-06-15

Helium ions of 500 keV were implanted with a fluence of 1.4 x 10{sup 17} ion/cm{sup 2} into various lithium silicates to investigate whether a threshold level of helium retention exists in Li-containing silicate ceramics similar to that found in SiO{sub x} in previous work. The composition and phases of the as prepared lithium silicates were determined by proton backscattering spectrometry (p-BS) and X-ray diffraction (XRD) methods with an average error of {+-}10%. Electrostatic charging of the samples was successfully eliminated by wrapping the samples in Al foil. The amounts of the retained helium within the samples were determined by subtracting the non-implanted spectra from the implanted ones. The experimental results show a threshold in helium retention depending on the Li concentration. Under 20 at.% all He is able to escape from the material; at around 30 at.% nearly half of the He, while over 65 at.% all implanted He is retained. With compositions expressed in SiO{sub 2} volume percentages, a trend similar to those reported of SiO{sub x} previously is found.

A Retention Assessment Process: Utilizing Total Quality Management Principles and Focus Groups

Science.gov (United States)

Codjoe, Henry M.; Helms, Marilyn M.

2005-01-01

Retaining students is a critical topic in higher education. Methodologies abound to gather attrition data as well as key variables important to retention. Using the theories of total quality management and focus groups, this case study gathers and reports data from current college students. Key results, suggestions for replication, and areas for…

The dust retention capacities of urban vegetation-a case study of Guangzhou, South China.

Science.gov (United States)

Liu, Lu; Guan, Dongsheng; Peart, M R; Wang, Gang; Zhang, Hui; Li, Zhiwei

2013-09-01

Urban vegetation increasingly plays an important role in the improvement of the urban atmospheric environment. This paper deals with the dust retention capacities of four urban tree species (Ficus virens var. sublanceolata, Ficus microcarpa, Bauhinia blakeana, and Mangifera indica Linn) in Guangzhou. The dust-retaining capacities of four tree species are studied under different pollution intensities and for different seasons. Remote sensing imagery was used to estimate the total aboveground urban vegetation biomass in different functional areas of urban Guangzhou, information that was then used to estimate the dust-retaining capacities of the different functional areas and the total removal of airborne particulates in urban Guangzhou by foliage. The results showed that urban vegetation can remove dust from the atmosphere thereby improving air quality. The major findings are that dust retention, or capture, vary between the four species of tree studied; it also varied between season and between types of urban functional area, namely industrial, commercial/road traffic, residential, and clean areas. Dust accumulation over time was also studied and reached a maximum, and saturation, after about 24 days. The overall aboveground biomass of urban vegetation in Guangzhou was estimated to be 52.0 × 10(5) t, its total leaf area 459.01 km(2), and the dust-retaining capacity was calculated at 8012.89 t per year. The present study demonstrated that the foliage of tree species used in urban greening make a substantial contribution to atmospheric dust removal and retention in urban Guangzhou.

Antecedents of Truck Drivers’ Job Satisfaction and Retention Proneness

DEFF Research Database (Denmark)

Prockl, Günter; Teller, Christoph; Kotzab, Herbert

2017-01-01

is statistically significant. Financial and nonfinancial job properties affect satisfaction with one's employer whereas the former shows a lower impact compared to the latter. Satisfaction with the job and one's employer impacts retention proneness. The contribution of this study was to (1) add...... to the understanding of the factors that predict retention of truck drivers in relationship to job satisfaction and (2) highlight the different roles of financial and nonfinancial job properties in this specific work context.......The aim of this study was to (1) explore the antecedents of truck drivers’ job satisfaction, (2) identify the impact of financial and nonfinancial job properties on satisfaction with the job and with one's employer, and (3) the drivers’ proneness to retaining their jobs. Based on the extant...

Exploring recruitment, willingness to participate, and retention of low-SES women in stress and depression prevention

NARCIS (Netherlands)

Waerden, J.E.B. van der; Hoefnagels, C.C.J.; Jansen, M.W.J.; Hosman, C.M.H.

2010-01-01

Background Recruitment, willingness to participate, and retention in interventions are indispensable for successful prevention. This study investigated the effectiveness of different strategies for recruiting and retaining low-SES women in depression prevention, and explored which sociodemographic

Encopresis in children: a cyclical model of constipation and faecal retention.

Science.gov (United States)

Swanwick, T

1991-01-01

Encopresis afflicts one in 100 children causing considerable stigma and parental concern. General practitioners are in a position to help in most cases but are often deterred by the psychoanalytical theories which have been developed to explain this problem. It is currently accepted that children with encopresis tend to retain stools. This leads to constipation, overstretching of sphincters and resultant faecal soiling. Physical and psychological perpetuating factors result in retention once again, thus completing a cycle of constipation and retention. Various precipitant and predisposing factors can maintain this cycle. Once physical causes have been excluded a simple behavioural approach can be adopted aimed at retraining the bowel. By using laxatives to prevent retention, gaining the child's confidence, cooperation and understanding and involving both the family and school, encopresis can be successfully managed in general practice. PMID:1807329

Recruitment and retention of homeless individuals with mental illness in a housing first intervention study

Directory of Open Access Journals (Sweden)

Verena Strehlau, MD

2017-09-01

Full Text Available Background: Homeless individuals with mental illness are challenging to recruit and retain in longitudinal research studies. The present study uses information from the Vancouver site of a Canadian multi-city longitudinal randomized controlled trial on housing first interventions for homeless individuals. We were able to recruit 500 participants and retain large number of homeless individuals with mental illness; 92% of the participants completed the 6-month follow up interview, 84% the 24-month follow up, while 80% completed all follow-up visits of the study. Purpose: In this article, we describe the strategies and practices that we considered as critical for successful recruitment and retention or participants in the study. Methods: We discuss issues pertaining to research staff hiring and training, involvement of peers, relationship building with research participants, and the use of technology and social media, and managing challenging situations in the context of recruitment and retention of marginalized individuals. Conclusions: Recruitment and retention of homeless participant with mental illness in longitudinal studies is feasible. It requires flexible, unconventional and culturally competent strategies. Longitudinal research projects with vulnerable and hidden populations may benefit from extensive outreach work and collaborative approaches that are based on attitudes of mutual respect, contextual knowledge and trust. Keywords: Housing first intervention, Homelessness, Mental illness, Recruitment, Retention, Longitudinal study

Quantitative autoradiographic analysis of estradiol retention by cells in the preoptic area, hypothalamus and amygdala

International Nuclear Information System (INIS)

Morrell, J.I.; Krieger, M.S.; Pfaff, D.W.

1986-01-01

These experiments were done to compare quantitatively, on a cell-by-cell basis, estradiol retention by cells in the medial preoptic area, arcuate nucleus, ventrolateral subdivision of the ventromedial nucleus, and the caudal half of the medial nucleus of the amygdala. The steroid autoradiograms were prepared from 2 μ sections of brains from overlectomized, adrenalectomized adult female rats that had been infused intravenously with [ 3 H] estradiol (E 2 ) in a regimen which kept circulating hormone concentration at or above proestrus levels for 3-4 h. Even in these brain regions, containing the most dense collections of E 2 -concentrating cells, a maximum of only 27-61% of the cells concentrated E 2 . Therefore, in these regions only a particular subset of the cells retain hormone; other cells in the region do not retain hormone. Frequency distribution histograms of the number of grains per cell versus the number of cells in each region showed a wide range in the amount of E 2 retained per cell, and no modes among E 2 -retaining cells. The data followed a distribution markedly different from that predicted by a simple Poisson distribution, confirming that E 2 -retention does not result from a random, passive process such as diffusion. The overall quantitative characteristics of the frequency distribution histograms were similar across the four brain areas. (orig./MG)

Nitrogen Saturation in Highly Retentive Watersheds?

Science.gov (United States)

Daley, M. L.; McDowell, W. H.

2009-12-01

anthropogenic sources of N that are not retained in the watershed and maintaining high rates of N retention will be of utmost concern for coastal managers.

Localization of plutonium retention in the small intestine of the neonatal rat, guinea pig, baboon and macaca after Pu-citrate ingestion

International Nuclear Information System (INIS)

Fritsch, P.; Lataillade, G.; Beauvallet, M.; L'Hullier, I.; Lepage, M.; Metivier, H.; Masse, R.; Moutairou, K.; avi, 526, Republique Populaire du Benin)

1988-01-01

The retention of Pu-citrate in the gastrointestinal wall was compared at similar post ingestion times after ingestion at 2 days of age by rats and guinea pigs and at 1 to 34 days by neonatal primates. The small intestine was the main site of the Pu retention in all species. In rats and primates, most of the Pu was retained in the distal ileum, whereas in guinea pigs it was more homogeneously distributed. In the rats, Pu was retained in the epithelial cells on villi, but in the guinea pigs and primates it was confined to the macrophages under the epithelial cells in the lacteal region. (author)

Differential retention of metabolic genes following whole-genome duplication.

Science.gov (United States)

Gout, Jean-François; Duret, Laurent; Kahn, Daniel

2009-05-01

Classical studies in Metabolic Control Theory have shown that metabolic fluxes usually exhibit little sensitivity to changes in individual enzyme activity, yet remain sensitive to global changes of all enzymes in a pathway. Therefore, little selective pressure is expected on the dosage or expression of individual metabolic genes, yet entire pathways should still be constrained. However, a direct estimate of this selective pressure had not been evaluated. Whole-genome duplications (WGDs) offer a good opportunity to address this question by analyzing the fates of metabolic genes during the massive gene losses that follow. Here, we take advantage of the successive rounds of WGD that occurred in the Paramecium lineage. We show that metabolic genes exhibit different gene retention patterns than nonmetabolic genes. Contrary to what was expected for individual genes, metabolic genes appeared more retained than other genes after the recent WGD, which was best explained by selection for gene expression operating on entire pathways. Metabolic genes also tend to be less retained when present at high copy number before WGD, contrary to other genes that show a positive correlation between gene retention and preduplication copy number. This is rationalized on the basis of the classical concave relationship relating metabolic fluxes with enzyme expression.

Recruitment and retention of low-income minority women in a behavioral intervention to reduce smoking, depression, and intimate partner violence during pregnancy

Directory of Open Access Journals (Sweden)

Murray Kennan B

2007-09-01

Full Text Available Abstract Background Researchers have frequently encountered difficulties in the recruitment and retention of minorities resulting in their under-representation in clinical trials. This report describes the successful strategies of recruitment and retention of African Americans and Latinos in a randomized clinical trial to reduce smoking, depression and intimate partner violence during pregnancy. Socio-demographic characteristics and risk profiles of retained vs. non-retained women and lost to follow-up vs. dropped-out women are presented. In addition, subgroups of pregnant women who are less (more likely to be retained are identified. Methods Pregnant African American women and Latinas who were Washington, DC residents, aged 18 years or more, and of 28 weeks gestational age or less were recruited at six prenatal care clinics. Potentially eligible women were screened for socio-demographic eligibility and the presence of the selected behavioral and psychological risks using an Audio Computer-Assisted Self-Interview. Eligible women who consented to participate completed a baseline telephone evaluation after which they were enrolled in the study and randomly assigned to either the intervention or the usual care group. Results Of the 1,398 eligible women, 1,191 (85% agreed to participate in the study. Of the 1,191 women agreeing to participate, 1,070 completed the baseline evaluation and were enrolled in the study and randomized, for a recruitment rate of 90%. Of those enrolled, 1,044 were African American women. A total of 849 women completed the study, for a retention rate of 79%. Five percent dropped out and 12% were lost-to-follow up. Women retained in the study and those not retained were not statistically different with regard to socio-demographic characteristics and the targeted risks. Retention strategies included financial and other incentives, regular updates of contact information which was tracked and monitored by a computerized data

Consideration of Cosmetic Surgery As Part of Women’s Benefit-Provisioning Mate Retention Strategy

Directory of Open Access Journals (Sweden)

Mohammad Atari

2017-08-01

Full Text Available Individuals perform mate retention behaviors to minimize the risk of partner infidelity and relationship dissolution. The current study investigates whether consideration of cosmetic surgery can be conceptualized as part of a broader strategy of mate retention for women, but not men. We hypothesized that women’s consideration of cosmetic surgery would be positively associated with performance frequencies of Benefit-Provisioning and Cost-Inflicting mate retention behaviors. We recruited 203 individuals (54% women in committed heterosexual relationships from Tehran, Iran. Results indicate a positive association between consideration of cosmetic surgery and Benefit-Provisioning mate retention behaviors for women, but not men. There was no association between consideration of cosmetic surgery and Cost-Inflicting mate retention behaviors. Women therefore may consider cosmetic surgery to improve their physical attractiveness as part of a Benefit-Provisioning strategy to retain a long-term mate. We discuss limitations of the study and highlight future directions for research from an evolutionary perspective.

Consideration of Cosmetic Surgery As Part of Women’s Benefit-Provisioning Mate Retention Strategy

Science.gov (United States)

Atari, Mohammad; Barbaro, Nicole; Sela, Yael; Shackelford, Todd K.; Chegeni, Razieh

2017-01-01

Individuals perform mate retention behaviors to minimize the risk of partner infidelity and relationship dissolution. The current study investigates whether consideration of cosmetic surgery can be conceptualized as part of a broader strategy of mate retention for women, but not men. We hypothesized that women’s consideration of cosmetic surgery would be positively associated with performance frequencies of Benefit-Provisioning and Cost-Inflicting mate retention behaviors. We recruited 203 individuals (54% women) in committed heterosexual relationships from Tehran, Iran. Results indicate a positive association between consideration of cosmetic surgery and Benefit-Provisioning mate retention behaviors for women, but not men. There was no association between consideration of cosmetic surgery and Cost-Inflicting mate retention behaviors. Women therefore may consider cosmetic surgery to improve their physical attractiveness as part of a Benefit-Provisioning strategy to retain a long-term mate. We discuss limitations of the study and highlight future directions for research from an evolutionary perspective. PMID:28855884

Torque resistance of different stainless steel wires commonly used for fixed retainers in orthodontics.

Science.gov (United States)

Arnold, Dario T; Dalstra, Michel; Verna, Carlalberta

2016-06-01

Movements of teeth splinted by fixed retention wires after orthodontic treatment have been observed. The aetiological factors for these movements are unknown. The aim of this in vitro study was to compare the resistance to torque of different stainless steel wires commonly used for fixed retainers in orthodontics. Torquing moments acting on a retainer wire were measured in a mechanical force testing system by applying buccal crown torque to an upper lateral incisor in both a 3-teeth and in a 2-teeth setup. Seven stainless steel wires with different shape, type (plain, braided, coaxial, or chain) and dimensions were selected for this study. For a torquing angle of 16.2° in the 3-teeth setup torsion moments can vary between 390 cNmm and 3299 cNmm depending on the retainer wire. For the 2-teeth setup the torsion moments are much smaller. Exposure to the flame of a butane-gas torch for 10 seconds to anneal the wire reduces the stiffness of the retainer wire. Clinicians must select wires for fixed retainers very carefully since the difference in resistance to torque is large. A high level of torque control can be achieved with a plain 0.016 × 0.016-inch or a braided 0.016 × 0.022-inch stainless steel wire. A tooth attached by a retainer wire to only one neighbouring tooth is less resistant to torque than a tooth connected to two neighbouring teeth. Annealing a retainer wire with a flame reduces the stiffness of the wire markedly and can lead to a non-uniform and non-reproducible effect.

Challenges in Retaining and Attracting Employees to the City of Västerås

OpenAIRE

Kämpe, Juliana

2012-01-01

Employee retention is one of the biggest challenges for Human Resources Management nowadays. Change itself has become a daily routine in organizations. In this master thesis I investigate employers’ and employees’ perceptions on their employment relationship, through the lens of the psychological contract, looking closely to the role of family-friendly practices on offering work-life balance, thus retaining and attracting employees. This qualitative case study of the City of Västerås has show...

The Relationship between Curricular Physical Activity and College Retention after the First Year

Science.gov (United States)

Bounds, Laura E.

2014-01-01

College retention has become increasingly important for many reasons. Individuals who attain bachelor's degrees, on average, have higher earning power and more career options than individuals with only a high school degree. Higher education institutes also benefit when students are retained and graduate. With the most recent budget crisis, higher…

An integrated dataset on organisational retention attributes and commitment of selected ICT and accounting firms

Directory of Open Access Journals (Sweden)

Odunayo Salau

2018-06-01

Full Text Available The article presented an integrated data on organisational retention strategies and commitment of selected ICT and Accounting firms in Nigeria. The study adopted a quantitative approach with a survey research design to establish the major determinants of employee retention strategies. The population of this study included staff and management of the selected firms. Data was analysed with the use of structural equation modelling and the field data set is made widely accessible to enable critical or a more comprehensive investigation. The findings identified critical attraction factors for the retention of sampled firms. It was recommended that ICT firms will need to adopt consistent range of strategies to attract and retain people with the right ICT skills, in the right place and at the right time. Keywords: Retention, Commitment, Reward, Satisfaction, Performance

Potential possibilities of water retention in agricultural loess catchments

Directory of Open Access Journals (Sweden)

Zubala Tomasz

2016-09-01

Full Text Available The growing water deficit and the increased demand for water, as well as economic problems and inadequate spatial planning in many regions indicate a necessity of developing more effective rules of programming and realisation of works concerning the water management in small catchments. The paper presents a sample analysis of the possibilities of increasing water retention in the agricultural loess catchments with periodic streams. The scope of the study included the determination of physical parameters of selected sub-catchments (geometry, soil cover, land use, etc. and of the sources of threat to water resources, resulting from construction and geomorphological conditions. Pre-design assumptions of dammings were developed, taking into account anti-erosion protective measures, and treatments increasing the landscape retention of water were proposed. Creating surface retention objects should be an important source of water in simplified agroecosystems, especially in regions, where productivity to a great extent depends on natural weather conditions. Proper management of the fourth-order loess basin of the Ciemięga River (area of about 150 km2, the presence of 50 lateral valleys could give a temporary reservoir retention reaching 500 thousand m3. Farmers should be encouraged to seek “own water sources” (including the accumulation of water within wasteland, using appropriate economic instruments (tax reliefs for the documented volume of retained water, e.g. in small retention reservoirs.

Sponge retention within the abdominal cavity: presentation forms and radiological diagnosis

International Nuclear Information System (INIS)

Pastor Santovena, S.; Fernandez Ramos, J.; Diaz Riudavets, M.C.; Rodriguez Delgado, L.E.; Torres Diaz, M.; Pitti Reyes, S.; Toledo Trujillo, F.

1994-01-01

The incidence of surgical sponge retention within the abdominal cavity has been estimated to range between 1:1000 and 1:5000. This study deals with the radiological, ultrasonographic (US) and computed tomographic (CT) findings, with and without radiolabeling, in four cases in which sponges were retained in the abdominal cavity for different lengths of time, each of which followed a different course. (Author)

Retention of gaseous fission products in reprocessing LMFBR fuels

International Nuclear Information System (INIS)

Burch, W.D.; Yarbro, O.O.; Groenier, W.S.; Stephenson, M.J.

1976-05-01

The report is devoted to status of the development programme at the Oak Ridge National Laboratory on methods for retaining iodine-131 and 129, Krypton-85, Tritium and Carbon-14 in reprocessing LMFBR fuels. The Iodox process, Fluorocarbon absorption process and Voloxidation process are described for retention of iodine, Krypton-85 and Tritium, respectively. Flowsheets for the different processes are given and results of experimental runs in small engineering-scale equipment are reported

Hydrogen retention properties of co-deposition under high-density plasmas in TRIAM-1M

International Nuclear Information System (INIS)

Tokitani, M.; Miyamoto, M.; Tokunaga, K.; Fujiwara, T.; Yoshida, N.; Sakamoto, M.; Zushi, H.; Hanada, K.; TRIAM Group,; Nagata, S.; Tsuchiya, B.

2007-01-01

Retention of hydrogen in co-deposits formed under high-density plasma discharge in TRIAM-1M was studied. In order to quantify the retained hydrogen, material probe experiments were performed under the high-density (n at e ∼10 19 m -3 ) discharges. After the exposure to the plasma, the quantitative analysis of deposition, hydrogen retention, and microscopic modification of specimens were performed by means of ion beam analysis and transmission electron microscopy. The co-deposits mainly consisted of Mo. The deposition rate of Mo was about ten times higher than that of the low-density discharge case. The hydrogen concentrations (H/Mo) retained in the co-deposits were 0.06-0.17, which was much higher than that in bulk-Mo and almost equal to the low-density case. These results indicate that as long as the co-deposition layers are continuously formed, strong wall pumping in TRIAM-1M is maintained during the discharges

Employee retention: a customer service approach.

Science.gov (United States)

Gerson, Richard F

2002-01-01

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

Prosthetic rehabilitation of large mid-facial defect with magnet-retained silicone prosthesis

Directory of Open Access Journals (Sweden)

Kirti Jajoo Shrivastava

2015-01-01

Full Text Available Rehabilitation of maxillofacial defect patients is a challenging task. The most common prosthetic treatment problem with such patients is, getting adequate retention, stability, and support. In cases of large maxillofacial defect, movement of the prosthesis is inevitable. The primary objectives in rehabilitating the maxillofacial defect patients are to restore the function of mastication, deglutition, speech, and to achieve normal orofacial appearance. This clinical report describes maxillofacial prosthetic rehabilitation of large midfacial defect including orbit along with its contents, zygoma and soft tissues including half of the nose, cheeks, upper lip of left side, accompanying postsurgical microstomia and orofacial communication, which resulted from severe fungal infection mucormycosis. The defect in this case was restored with magnet retained two piece maxillofacial prosthesis having hollow acrylic resin framework and an overlying silicone facial prosthesis. The retention of prosthesis was further enhanced with the use of spectacles. This type of combination prosthesis enhanced the cosmesis and functional acceptability of prosthesis.

Effect of dose on lead retention and distribution in suckling and adult female mice

International Nuclear Information System (INIS)

Keller, C.A.; Doherty, R.A.

1980-01-01

Single doses of lead (trace to 445 mg/kg) were administered per os to suckling and adult mice. Both groups exhibited dose-independent lead retention when doses of 4 to 445 mg/kg were administered. However, developmental differences in the fraction of initial dose (FID) retained were evident for all doses administered. A much larger FID was retained in both age groups following administration of carrier-free 203 Pb. The results are consistent with a mechanism of gastrointestinal lead absorption comprising two or more processes. Developmental differences were also observed in organ lead concentration relative to whole body concentration for kidneys, skull and brain 6 days following lead administration. Lead retentions (relative to whole body retention) in brain and in bone were linearly related to dose of lead administered in both suckling and adult age groups. Though uptake of lead into brain and into femur was observed to be directly related to dose over a wide range, relative blood lead concentrations were not linearly correlated with dose administered. The relationships between lead concentrations of blood and organ(s) were also shown to be nonlinear relative to dose. However, blood lead concentration was found to be a reliable indicator of kidney and liver lead concentrations following an acute lead exposure

The effect of retained intramedullary nails on tibial bone mineral density.

Science.gov (United States)

Allen, J C; Lindsey, R W; Hipp, J A; Gugala, Z; Rianon, N; LeBlanc, A

2008-07-01

Intramedullary nailing has become a standard treatment for adult tibial shaft fractures. Retained intramedullary nails have been associated with stress shielding, although their long-term effect on decreasing tibial bone mineral density is currently unclear. The purpose of this study was to determine if retained tibial intramedullary nails decrease tibial mineral density in patients with successfully treated fractures. Patients treated with statically locked intramedullary nails for isolated, unilateral tibia shaft fractures were studied. Inclusion required that fracture had healed radiographically and that the patient returned to the pre-injury activity level. Data on patient demographic, fracture type, surgical technique, implant, and post-operative functional status were tabulated. Dual energy X-ray absorptiometry was used to measure bone mineral density in selected regions of the affected tibia and the contralateral intact tibia. Image reconstruction software was employed to ensure symmetry of the studied regions. Twenty patients (mean age 43; range 22-77 years) were studied at a mean of 29 months (range 5-60 months) following intramedullary nailing. There was statistically significant reduction of mean bone mineral density in tibiae with retained intramedullary nails (1.02 g/cm(2) versus 1.06 g/cm(2); P=0.04). A significantly greater decrease in bone mineral density was detected in the reamed versus non-reamed tibiae (-7% versus +6%, respectively; P<0.05). The present study demonstrates a small, but statistically significant overall bone mineral density decrease in healed tibiae with retained nails. Intramedullary reaming appears to be a factor potentiating the reduction of tibia bone mineral density in long-term nail retention.

Retention capacity of samarium (III) in zircon for it possible use in retaining walls for confinement of nuclear residues

International Nuclear Information System (INIS)

Garcia G, N.

2006-01-01

Mexico, as country that produces part of its electric power by nuclear means, should put special emphasis in the development of technologies guided to the sure and long term confinement of the high level nuclear residuals. This work studies the capacity that has the natural zircon to retain to the samarium (III) in solution, by what due, firstly, to characterize the zircon for technical instrumental to determine the purity and characteristic of the mineral in study. The instrumental techniques that were used to carry out the physicochemical characterization were the neutron activation analysis (NAA), the infrared spectroscopy (IS), the thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), semiquantitative analysis, dispersive energy spectroscopy (EDS), X-ray diffraction (XRD) and luminescence technique. The characterization of the surface properties carries out by means of the determination of the surface area using the BET multipoint technique, acidity constants, hydration time, the determination of the point of null charge (pH PCN ) and density of surface sites (D s ). The luminescence techniques were useful to determine the optimal point hydration of the zircon and for the quantification of the samarium, for that here intends the development of both analysis techniques. With the adjustment of the titration curves in the FITEQL 4 package the constants of surface acidity in the solid/liquid interface were determined. To the finish of this study it was corroborated that the zircon is a mineral that presents appropriate characteristics to be proposed as a contention barrier for the deep geologic confinement. With regard to the study of adsorption that one carries out the samarium retention it is superior to 90% under the described conditions. This investigation could also be applicable in the confinement of dangerous industrial residuals. (Author)

A longitudinal assessment of vocabulary retention in symbol-competent chimpanzees (Pan troglodytes).

Science.gov (United States)

Beran, Michael J; Heimbauer, Lisa A

2015-01-01

A number of studies from the 1960s to 1990s assessed the symbolic competence of great apes and other animals. These studies provided varying forms of evidence that some species were capable of symbolically representing their worlds, both through productive symbol use and comprehension of symbolic stimuli. One such project at the Language Research Center involved training chimpanzees (Pan troglodytes) to use lexigram symbols (geometric visual stimuli that represented objects, actions, locations, and individuals). Those studies now are more than 40 years old, and only a few of the apes involved in those studies are still alive. Three of these chimpanzees (and a fourth, control chimpanzee) were assessed across a 10-year period from 1999 to 2008 for their continued knowledge of lexigram symbols and, in the case of one chimpanzee, the continued ability to comprehend human speech. This article describes that longitudinal assessment and outlines the degree to which symbol competence was retained by these chimpanzees across that decade-long period. All chimpanzees showed retention of lexigram vocabularies, although there were differences in the number of words that were retained across the individuals. One chimpanzee also showed continual retention of human speech perception. These retained vocabularies largely consisted of food item names, but also names of inedible objects, locations, individuals, and some actions. Many of these retained words were for things that are not common in the daily lives of the chimpanzees and for things that are rarely requested by the chimpanzees. Thus, the early experiences of these chimpanzees in symbol-rich environments have produced long-lasting memories for symbol meaning, and those competencies have benefited research in a variety of topics in comparative cognition.

Retention predictors related to intensive outpatient programs for substance use disorders.

Science.gov (United States)

Veach, L J; Remley, T P; Kippers, S M; Sorg, J D

2000-08-01

The purpose of this research was to expand knowledge in the current literature regarding treatment retention in intensive outpatient substance abuse treatment programs. The sample in this study participated in a hospital-based program accredited by the Joint Commission on Accreditation for Health Organizations (JCAHO) that utilized the Minnesota model. Specifically, this inquiry investigated whether treatment retention would be predicted by gender, age, employment status, number of problems on the treatment plan, whether the referral was related to driving while intoxicated (DWI), marital status, race, and whether each of the following substance problems was listed as the client's primary DSM-IV diagnosis: alcohol dependence, cocaine dependence, polysubstance dependence, opioid dependence, sedative/hypnotic dependence, cannabis dependence, other (or unknown) dependence, alcohol abuse, cannabis abuse, amphetamine abuse, and caffeine intoxication. Findings indicated that those retained in treatment, when compared to those who dropped out, had significantly more problems on their treatment plans, were more likely to be alcoholics, were less often cocaine addicts, and were more likely to be employed. The results of this study suggest that clients with this profile have increased likelihood of being retained in intensive outpatient substance abuse treatment programs.

Actual drawing of histological images improves knowledge retention.

Science.gov (United States)

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

2016-01-01

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

A unique method of retaining orbital prosthesis with attachment systems - a clinical report.

Science.gov (United States)

Guttal, Satyabodh S; Akash, N R; Prithviraj, D R; Lekha, K

2014-06-01

Diminution of the orbital contents post-surgical removal of a malignant tumor can have a severe psychological impact on the patient in terms of function and esthetics. Therefore, esthetic remedy should be planned subsequently, since tumor obliteration precedes cosmetic concern. A convenient option for successful rehabilitation in such patients is a simple, user-friendly, removable orbital prosthesis. Retention of the prosthesis is one of the key factors for the successful rehabilitation. Spectacle frame, conformers, adhesives, osseointegrated implants, magnets or buttons have been used to impart retention to the prosthesis. The use of semi precision attachments in maxillofacial prostheses is limited to the osseointegrated prostheses. This case report describes a conventional spectacle frame technique, to retain the silicone orbital prosthesis using two different types of stud attachments viz., dalla bona and O-ring attachment systems. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Retention factors of management staff in the maintenance phase of their careers in local government

Directory of Open Access Journals (Sweden)

Mervin Munsamy

2009-10-01

Full Text Available Organisations require an employer value proposition (EVP to attract and retain people in management. This study was undertaken to understand the key retention factors that influence experienced management employees, in the maintenance phase of their careers, to remain employed at a local government organisation. Retention factors inform the organisation’s EVP. A qualitative, empirical-analytical research paradigm with a modernist approach was adopted. Data were obtained through purposive sampling (n = 10 by way of semi-structured interviews. A theoretical framework was used against which data could be deducted and compared. Sixteen key factors were identified, of which Job Aligned with Personal Meaning or Passion emerged as the strongest retention factor among the study’s participants.

Literature review of the studies on uptake, retention and distribution of radionuclides by the foetus

International Nuclear Information System (INIS)

Lamothe, E.S.

1989-10-01

This report summarizes the available literature from the last 10 years dealing with studies on uptake, retention and distribution of radionuclides by an embryo or foetus following maternal intakes. The review concentrates on isotopes commonly used by Canadian licensees. From the animal studies and from the limited human data, it is evident that after maternal contamination, the embryo or foetus accumulates and retains most radionuclides. Very little human data is available and a large fraction of the quoted values for human foetal dose retention are obtained from extrapolation from animal experiments. The information obtained in animal experiments is useful in determining general patterns of retention and distributions of radionuclides within the foetoplacental unit

Nuclear reactor melt-retention structure to mitigate direct containment heating

International Nuclear Information System (INIS)

Tutu, N.K.; Ginsberg, T.; Klages, J.R.

1991-01-01

This patent describes a nuclear reactor melt-retention structure that functions to retain molten core material within a melt retention chamber to mitigate the extent of direct containment heating. The structure being adapted to be positioned within or adjacent to a pressurized or boiling water nuclear reactor containment building at a location such that at least a portion of the melt retention structure is lower than and to one side of the nuclear reactor pressure vessel, and such that the structure is adjacent to a gas escape channel means that communicates between the reactor cavity and the containment building of the reactor. It comprises a melt-retention chamber, wall means defining a passageway extending between the reactor cavity underneath the reactor pressure vessel and one side of the chamber, the passageway including vent means extending through an upper wall portion thereof. The vent means being in communication with the upper region of the reactor containment building, whereby gas and steam discharged from the reactor pressure vessel are vented through the passageway and vent means into the gas-escape channel means and the reactor containment building

'Any body is better than nobody?' Ethical questions around recruiting and/or retaining health professionals in rural areas.

Science.gov (United States)

Simpson, C; McDonald, F

2011-01-01

The literature on recruiting and/or retaining health professionals in rural areas focuses primarily on the development of recruitment and retention strategies and assessing whether such strategies are effective. The objective of this article is to argue that it is important for all stakeholders involved in rural recruitment and/or retention processes to consider their decisions and actions from an ethics perspective. Recruitment and/or retention processes are not value neutral and it is important to understand their ethical dimensions. From the literature, elements of the recruitment and/or retention strategies that have been employed were identified and organised in respect of levels of governance (namely, the levels of health system/government, community, and individual health professionals). The elements identified in these levels were subjected to analysis to identify their ethical dimensions and to determine whether a clash or complement of values arose at each level of governance or between governance levels. There is very little literature in this area that considers the ethical dimensions of rural recruitment and/or retention processes. However, all policies and practices have ethical dimensions that need to be identified and understood as they may have significant implications for recruitment and/or retention processes. This article recommends the application of an ethics perspective when reflecting on rural recruitment and/or retention strategies. The collective decisions of all involved in rural recruitment and/or retention processes may fundamentally influence the 'health' (broadly understood) of rural communities.

Level and pattern of overstory retention influence rates and forms of tree mortality in mature, coniferous forests of the Pacific Northwest, USA

Science.gov (United States)

Lauren S. Urgenson; Charles B. Halpern; Paul D. Anderson

2013-01-01

Mortality of retained trees can compromise the ecological objectives of variable-retention harvest. We used a large-scale experiment replicated at six locations in western Washington and Oregon to examine the influences of retention level (40% vs. 15% of original basal area) and its spatial pattern (aggregated vs.dispersed) on the rate and form of tree mortality for 11...

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

Science.gov (United States)

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

2009-06-01

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

76 FR 71040 - Agency Information Collection Activities; Proposed Collection; Comment Request; Record Retention...

Science.gov (United States)

2011-11-16

... with soy protein. The records required to be retained by Sec. 101.82(c)(2)(ii)(B) are the records, e.g... Requirements for the Soy Protein and Risk of Coronary Heart Disease Health Claim AGENCY: Food and Drug... notice solicits comments on the record retention requirements for the soy protein and coronary heart...

Total rewards: A study of artisan attraction and retention within a South African context

Directory of Open Access Journals (Sweden)

Anton Schlechter

2014-11-01

Full Text Available Orientation: The shortage of artisan skills remains a serious challenge in South Africa andis forcing employers to investigate which total reward factors contribute to the attractionand retention of this critical skills segment, as undifferentiated retention strategies are nolonger useful or even appropriate. Research purpose: The aim of this study was to further develop understanding of the total rewardfactors and the ideal combination and relative amount of total rewards that attract and retainartisans, including artisans from various race groups and age cohorts, using a novel approach. Motivation for the study: Limited research is available on the total reward factors and theideal combination and relative amount of total rewards that attract and retain artisans. Furtherknowledge in this area will allow organisations to develop reward models that better attractand retain artisans. Method: The study followed both a quantitative and qualitative research approach,whilst adopting a descriptive research design. Using this mixed method, primary datawere collected from individuals by means of two focus groups discussions: (1 a groupof human resource and remuneration managers (n = 4 and (2 a group of artisans (n = 7.These results were used to develop two questionnaires that were distributed to artisans (n = 143. Data from Questionnaire 1 were analysed using descriptive statistics and factoranalysis. Conjoint analysis was employed to identify an ideal total rewards compositionbased on responses from Questionnaire 2. Main findings: The results of the choice-based modelling (conjoint analysis revealed thatthree total rewards attributes were consistently deemed to be important in the retention ofartisans. These were (in order of priority: environment (work-life balance, compensation(level and compensation (variable. Environment (work-life balance was considered14.64% more important than compensation (level within the overall sample as well aswithin the

Effect of bar cross-section and female housing material on retention of mandibular implant bar overdentures: A comparative in vitro study

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Elsayed A Abdel-Khalek

2017-01-01

Conclusions: Within the limitation of this in vitro study and for a similar period of service, heat-cured silicone female housing for Hader bar could maintain greater retention for two-implant-retained overdentures than provided by conventional plastic clip after 1.5 year. The oval bar recorded reasonable initial retention values and maintained these values for 1.5 years of service.

Unraveling complexities of velocity dependent retention and release parameters for E. coli in saturated porous media

Science.gov (United States)

Escherichia coli transport and release experiments were conducted to investigate the pore-water velocity (v) dependency of the sticking efficiency (a), the fraction of the solid surface area that contributed to retention (Sf), the percentage of injected cells that were irreversibly retained (Mirr), ...

SECONDARY RETENTION OF PERMANENT MOLARS - AN ASSESSMENT OF ANKYLOSIS BY SCANNING ELECTRON AND LIGHT-MICROSCOPY

NARCIS (Netherlands)

RAGHOEBAR, GM; JANSEN, HWB; JONGEBLOED, WL; BOERING, G; VISSINK, A

Secondary retention refers to the cessation of eruption of a tooth after emergence. This may be the result of pathological changes in the periodontal ligament. The aim of this study was to describe the morphological and histological aspects of the radicular surface of secondarily retained permanent

Oral Health-Related Quality of Life in Edentulous Patients with Two- vs Four-Locator-Retained Mandibular Overdentures: A Prospective, Randomized, Crossover Study.

Science.gov (United States)

Karbach, Julia; Hartmann, Sinsa; Jahn-Eimermacher, Antje; Wagner, Wilfried

2015-01-01

To compare the oral health-related quality of life (OHRQoL) in a prospective, randomized crossover trial in patients with mandibular overdentures retained with two or four locators. In 30 patients with edentulous mandibles, four implants (ICX-plus implants [Medentis Medical]) were placed in the intraforaminal area. Eight weeks after transgingival healing, patients were randomly assigned to have two or four implants incorporated in the prosthesis. After 3 months, the retention concepts were switched. The patients with a two-implant-supported overdenture had four implants incorporated, whereas patients with a four-implant-supported overdenture had two retention locators taken out. After 3 more months, all four implants were retained in the implant-supported overdenture in every patient. To measure OHRQoL of the patients, the Oral Health Impact Profile 14, German version (OHIP-14 G), was used. A considerable increase in OHRQoL could be seen in all patients after the prosthesis was placed on the implants. Also, a statistically significant difference of OHRQoL could be seen in the OHIP-14 G scores between two-implant and four-implant overdentures. Patients had a higher OHRQoL after incorporation of four implants in the overdenture compared with only two implants. Patients with implant-retained overdentures had better OHRQoL compared with those with conventional dentures. The number of incorporated implants in the locator-retained overdenture also influenced the increase in OHRQoL, with four implants having a statistically significant advantage over two implants.

Retention preferences and the relationship between total rewards, perceived organisational support and perceived supervisor support

Directory of Open Access Journals (Sweden)

Wilmien Smit

2015-08-01

Full Text Available Orientation: Currently there is much debate whether modifying traditional reward packages to focus on the preferences of multi-generations would be essential in attracting, motivating and retaining talent. Total reward factors, perceived organisational support and perceived supervisor support are distinct but related concepts, all of which appear to influence an employee’s decision to stay at an organisation. Research purpose: The objective of this study was to identify the different total reward components that multi-generations prefer as most important for retention. In essence, the study aims to establish possible relationships between multi-generations’ total reward components, perceived organisational support, and perceived supervisor support. Motivation for the study: This study is useful as it conducts a contemporary retention exploration that considers both the emerging demographic workforce shift and the new paradigm shift towards talent management. Research methodology: A quantitative, cross-sectional research design was applied to gather data from employees (N = 303 from different industry sectors in South African organisations. Main findings: The results showed that performance management and remuneration are considered to be the most important retention factors amongst multi-generation groups. Differences between total reward preferences and demographical variables, which include age, gender, race, industry and job level, were found. Practical/managerial implications: Organisations should design their reward packages by taking employees preferences into account. More specifically, organisations should focus on remuneration, performance management and development opportunities in order to retain scarce skills. Contribution/value additions: The results of the study can assist managers to design effective retention strategies, whilst also providing crucial information for the retention and motivation of employees.

Differential retention of pollen grains on clothing and the effectiveness of laboratory retrieval methods in forensic settings.

Science.gov (United States)

Webb, Julia C; Brown, Harriet A; Toms, Hannah; Goodenough, Anne E

2018-07-01

Forensic palynology has been important in criminal investigation since the 1950s and often provides evidence that is vital in identifying suspects and securing convictions. However, for such evidence to be used appropriately, it is necessary to understand the factors affecting taphonomic variability (i.e. the variability in the fate of pollen grains before they are found during forensic examination). Here, we test the relative amount of pollen retained on clothing after a period of simulated light or heavy wear based on pollen and fabric characteristics. We also test the efficiency of forensic laboratory protocols for retrieving pollen from fabrics for analysis. There was no statistically significant difference in retention of fresh or dried pollen on any fabric type. There was a substantial difference in pollen retention according to wear intensity, with considerably more pollen being retained after light wear than after heavy wear. Pollen from insect-pollinated species was retained at higher concentrations than pollen from wind-pollinated species. This pattern was consistent regardless of wear intensity but pollination type explained more of the variability in pollen retention after light wear. Fabric type was significantly related to pollen retention, but interacted strongly with plant species such that patterns were both complex and highly species-specific. The efficiency of removing pollen with the standard washing protocol differed substantially according to plant species, fabric type, and the interaction between these factors. The average efficiency was 67.7% but this ranged from 21% to 93%, demonstrating that previous assumptions on the reliability of the technique providing a representative sample for forensic use should be reviewed. This paper highlights the importance of understanding pollen and fabric characteristics when creating a pollen profile in criminal investigations and to ensure that evidence used in testimony is accurate and robust. Crown

What diversity management practices do hotel managers and employees view as important for retaining employees?

OpenAIRE

Twum, Sophia Araba

2015-01-01

Master's thesis in International hotel and tourism management Abstract Research shows that the hotel industry is noted for high rate of turnover. Again, diversity management practices have been found to be a good human resource tool helping to manage and retain diverse workforce. A lot of studies have been done on employee retention and diversity management separately but the two concepts are related therefore there is the need to look at them together. This thesis aims...

Determinants of feedback retention in soccer players

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Januário Nuno

2016-06-01

Full Text Available This study analyzed soccer players’ retention of coaches’ feedback during training sessions. We intended to determine if the retention of information was influenced by the athletes’ personal characteristic (age, gender and the sports level, the quantity of information included in coach’s feedback (the number of ideas and redundancy, athletes’ perception of the relevance of the feedback information and athletes’ motivation as well as the attention level. The study that was conducted over the course of 18 sessions of soccer practice, involved 12 coaches (8 males, 4 females and 342 athletes (246 males, 96 females, aged between 10 and 18 years old. All coach and athlete interventions were transposed to a written protocol and submitted to content analysis. Descriptive statistics and multiple linear regression were calculated. The results showed that a substantial part of the information was not retained by the athletes; in 65.5% of cases, athletes experienced difficulty in completely reproducing the ideas of the coaches and, on average, the value of feedback retention was 57.0%. Six variables with a statistically significant value were found: gender, the athletes’ sports level, redundancy, the number of transmitted ideas, athletes’ perception of the relevance of the feedback information and the athletes’ motivation level.

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

Science.gov (United States)

Ellenbecker, Carol Hall; Cushman, Margaret

2012-08-01

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

Hot-electron surface retention in intense short-pulse laser-matter interactions.

Science.gov (United States)

Mason, R J; Dodd, E S; Albright, B J

2005-07-01

Implicit hybrid plasma simulations predict that a significant fraction of the energy deposited into hot electrons can be retained near the surface of targets with steep density gradients illuminated by intense short-pulse lasers. This retention derives from the lateral transport of heated electrons randomly emitted in the presence of spontaneous magnetic fields arising near the laser spot, from geometric effects associated with a small hot-electron source, and from E fields arising in reaction to the ponderomotive force. Below the laser spot hot electrons are axially focused into a target by the B fields, and can filament in moderate Z targets by resistive Weibel-like instability, if the effective background electron temperature remains sufficiently low. Carefully engineered use of such retention in conjunction with ponderomotive density profile steepening could result in a reduced hot-electron range that aids fast ignition. Alternatively, such retention may disturb a deeper deposition needed for efficient radiography and backside fast ion generation.

Retention system and method for the blades of a rotary machine

Science.gov (United States)

Pedersen, Poul D.; Glynn, Christopher C.; Walker, Roger C.

2002-01-01

A retention system and method for the blades of a rotary machine for preventing forward or aft axial movement of the rotor blades includes a circumferential hub slot formed about a circumference of the machine hub. The rotor blades have machined therein a blade retention slot which is aligned with the circumferential hub slot when the blades are received in correspondingly shaped openings in the hub. At least one ring segment is secured in the blade retention slots and the circumferential hub slot to retain the blades from axial movement. A key assembly is used to secure the ring segments in the aligned slots via a hook portion receiving the ring segments and a threaded portion that is driven radially outwardly by a nut. A cap may be provided to provide a redundant back-up load path for the centrifugal loads on the key. Alternatively, the key assembly may be formed in the blade dovetail.

Quality Induction: The Effects of Comprehensive Induction on New Teacher Retention and Job Satisfaction

Science.gov (United States)

Hendricks-Harris, Mary Therese

2012-01-01

This investigation examined the effect of a comprehensive new teacher induction program on teacher retention and job satisfaction in one suburban school district. New teachers are retained at low rates, and districts are spending resources in an attempt to decrease this number. New teacher induction includes supports for new teachers in their…

Recruiting, Retaining and Engaging Men in Social Interventions: Lessons for Implementation Focusing on a Prison-Based Parenting Intervention for Young Incarcerated Fathers

Science.gov (United States)

Buston, Katie

2018-01-01

Recruiting, retaining and engaging men in social interventions can be challenging. The focus of this paper is the successful implementation of a parenting programme for incarcerated fathers, delivered in a Young Offender Institution (YOI) in Scotland. Reasons for high levels of recruitment, retention and engagement are explored, with barriers…

Early retention of 237Pu + 239Pu in mature beagles

International Nuclear Information System (INIS)

Lloyd, R.D.; McFarland, S.S.; Atherton, D.R.; Bruenger, F.W.; Taylor, G.N.; Mays, C.W.

1978-01-01

Five mature beagles, ranging in age from 57 to 84 months, were injected intravenously with about 0.05-0.1 μCi/kg of 239 Pu(IV) citrate to which tracer amounts of the photon-emitter 237 Pu had been added. Plutonium retention in liver and in non-liver tissue (mainly skeleton) was measured periodically in the living dogs for nearly 4 months after injection by a combination of total-body and partial-body counting. All excreta were collected during the first 21 days and analysed for their Pu content. One dog was sacrificed at 14 days and another at 118 days for distribution studies. About 17% (14-20%) of the injected Pu was excreted in the urine and feces in the first 3 weeks, about the same as that excreted in a corresponding time by beagles injected as young adults (14%), but substantially more than beagles injected as juveniles (11%). In contrasts to juvenile beagles injected at 3 months of age, in which early retention was about 12% in liver and 68% in the skeleton, mature beagles retained about 30% in liver and 50% in the skeleton. Retention in young adult beagles injected at 17 months of age was similar to that of mature dogs. Relative distribution of skeletal plutonium among various bones was similar in the mature animals to that seen previously in young adults, but quite different from that of juveniles. A notable exception was the humerus for which there was no significant difference (P>0.2) in the % of retained skeletal Pu represented by the humerus among the juvenile, young adult and mature dogs. (author)

The use of lithium as a marker for the retention of liquids in the oral cavity after rinsing.

Science.gov (United States)

Hanning, Sara M; Kieser, Jules A; Ferguson, Martin M; Reid, Malcolm; Medlicott, Natalie J

2014-01-01

The aim of this study was to validate the use of lithium as a marker to indicate the retention of simple liquids in the oral cavity and use this to determine how much liquid is retained in the oral cavity following 30 s of rinsing. This is a validation study in which saliva was spiked with known concentrations of lithium. Twenty healthy participants then rinsed their mouths with either water or a 1 % w/v carboxymethylcellulose (CMC) solution for 30 s before expectorating into a collection cup. Total volume and concentration of lithium in the expectorant were then measured, and the percentage of liquid retained was calculated. The mean amount of liquid retained was 10.4 ± 4.7 % following rinsing with water and 15.3 ± 4.1 % following rinsing with 1 % w/v CMC solution. This difference was significant (p < 0.01). Lithium was useful as a marker for the retention of liquids in the oral cavity, and a value for the amount of water and 1 % w/v CMC solution remaining in the oral cavity following a 30-s rinse was established. The present study quantifies the retention of simple fluids in the oral cavity, validating a technique that may be applied to more complex fluids such as mouth rinses. Further, the application of this method to specific population groups such as those with severe xerostomia may assist in developing effective saliva substitutes.

Phosphorus Retention (32P) by synthetic iron oxides

International Nuclear Information System (INIS)

Bittencourt, V.C.; Montanheiro, M.N.S.

1975-02-01

The P retention by iron oxides was characterized as a chemical adsorption process followed by a physical adsorption. The former process was very intense with initial amounts of added P but after a certain surface saturation is reached physical interaction occurs. It was supposed that the chemically adsorbed phosphate confers a negative charge on the iron oxides particles, which repels any further physical adsorbtion of the anion. However due to diffusion of phosphate ions into the internal layers of the iron oxides, their surface can retain further amounts of P [pt

Factors Affecting Female Lecturer Retention in Private Higher Institution in Perak

OpenAIRE

Juliana Abu Bakar; Zam Zuriyati Mohamad; S.A. Sharmeela-Banu

2015-01-01

The contribution of female lecturer in education profession is undeniable and their satisfaction is crucial to retain them in this field. This research was conducted with the aim to investigate the factors that influence the female lecturer satisfaction in private higher education institution in Perak, Malaysia. Subsequently it intends to examine the effect of female lecturer satisfaction on their job retention. Perceived Organization Support Theory and Theory of Organizational Equilibrium ha...

Refractance Window™ drying of haskap berry--preliminary results on anthocyanin retention and physicochemical properties.

Science.gov (United States)

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

2016-03-01

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

Hydrogen isotope distributions and retentions in the inner divertor tile of JT-60U

Energy Technology Data Exchange (ETDEWEB)

Oya, Y. [Radioisotope Center, University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032 (Japan)]. E-mail: yoya@ric.u-tokyo.ac.jp; Hirohata, Y. [Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Tanabe, T. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Shibahara, T. [Graduate School of Engineering, Nagoya University, Nagoya 464-8603 (Japan); Kimura, H. [Faculty of Science, Shizuoka University, Shizuoka 422-8529 (Japan); Oyaidzu, M. [Faculty of Science, Shizuoka University, Shizuoka 422-8529 (Japan); Arai, T. [Naka Fusion Establishment, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Masaki, K. [Naka Fusion Establishment, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Gotoh, Y. [Naka Fusion Establishment, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Okuno, K. [Faculty of Science, Shizuoka University, Shizuoka 422-8529 (Japan); Miya, N. [Naka Fusion Establishment, Japan Atomic Energy Research Institute, Naka-machi, Naka-gun, Ibaraki 311-0193 (Japan); Hino, T. [Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Tanaka, S. [Graduate School of Engineering, University of Tokyo, Tokyo 113-8656 (Japan)

2005-11-15

Retention profiles of hydrogen and deuterium in graphite tiles placed in the inner divertor region of JT-60U were analyzed by secondary ion mass spectroscopy (SIMS) and thermal desorption spectroscopy (TDS). The difference in hydrogen and deuterium retention behaviour is discussed considering the frequency of the strike-point hit and history of NBI heating power. It was found that most of hydrogen/deuterium was retained in the deposited layers, HH deposition layers/DD deposition layers or co-deposited with carbon. Owing to the higher heating power of DD discharges, the deuterium concentration in the DD deposition layers was much lower than that of hydrogen in the HH deposition layers. On the area showing no deposition, very shallow profile of deuterium dominated hydrogen profile. These results indicate that the tritium retention is strongly influenced by the history of discharge and temperatures. Tritium retention on graphite tiles and deposition layers could be significantly reduced with increasing the operation temperature.

Hydrogen isotope distributions and retentions in the inner divertor tile of JT-60U

International Nuclear Information System (INIS)

Oya, Y.; Hirohata, Y.; Tanabe, T.; Shibahara, T.; Kimura, H.; Oyaidzu, M.; Arai, T.; Masaki, K.; Gotoh, Y.; Okuno, K.; Miya, N.; Hino, T.; Tanaka, S.

2005-01-01

Retention profiles of hydrogen and deuterium in graphite tiles placed in the inner divertor region of JT-60U were analyzed by secondary ion mass spectroscopy (SIMS) and thermal desorption spectroscopy (TDS). The difference in hydrogen and deuterium retention behaviour is discussed considering the frequency of the strike-point hit and history of NBI heating power. It was found that most of hydrogen/deuterium was retained in the deposited layers, HH deposition layers/DD deposition layers or co-deposited with carbon. Owing to the higher heating power of DD discharges, the deuterium concentration in the DD deposition layers was much lower than that of hydrogen in the HH deposition layers. On the area showing no deposition, very shallow profile of deuterium dominated hydrogen profile. These results indicate that the tritium retention is strongly influenced by the history of discharge and temperatures. Tritium retention on graphite tiles and deposition layers could be significantly reduced with increasing the operation temperature

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

Directory of Open Access Journals (Sweden)

Pim A. de Ruijter

2014-11-01

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

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

Science.gov (United States)

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

2014-01-01

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

Retaining nurses in metropolitan areas: insights from senior nurse and human resource managers.

Science.gov (United States)

Drennan, Vari M; Halter, Mary; Gale, Julia; Harris, Ruth

2016-11-01

To investigate the views of senior nurse and human resource managers of strategies to retain hospital nurses in a metropolitan area. Against a global shortage, retaining nurses is a management imperative for the quality of hospital services. Semi-structured interviews, thematically analysed. Metropolitan areas have many health organisations in geographical proximity, offering nurses choices in employer and employment. Senior nurse and human resource managers recognised the complexity of factors influencing nurse turnover, including those that 'pulled' nurses out of their jobs to other posts and factors that 'pushed' nurses to leave. Four themes emerged in retaining nurses: strategy and leadership, including analysis of workforce and leavers' data, remuneration, the type of nursing work and career development and the immediate work environment. In contexts where multiple organisations compete for nurses, addressing retention through strategic leadership is likely to be important in paying due attention and apportioning resources to effective strategies. Aside from good human resource management practices for all, strategies tailored to different segments of the nursing workforce are likely to be important. This metropolitan study suggests attention should be paid to strategies that address remuneration, progressing nursing careers and the immediate work environment. © 2016 The Authors Journal of Nursing Management Published by John Wiley & Sons Ltd.

Chloroplast digestion and the development of functional kleptoplasty in juvenile Elysia timida (Risso, 1818 as compared to short-term and non-chloroplast-retaining sacoglossan slugs.

Directory of Open Access Journals (Sweden)

Elise Marie Jerschabek Laetz

Full Text Available Sacoglossan sea slugs are the only metazoans known to perform functional kleptoplasty, the sequestration and retention of functional chloroplasts within their digestive gland cells. Remarkably, a few species with this ability can survive starvation periods of 3-12 months likely due to their stolen chloroplasts. There are no reports of kleptoplast transfer from mother slug to either eggs or juveniles, demonstrating that each animal must independently acquire its kleptoplasts and develop the ability to maintain them within its digestive gland. We present here an investigation into the development of functional kleptoplasty in a long-term kleptoplast retaining species, Elysia timida. Laboratory-reared juvenile slugs of different post-metamorphic ages were placed in starvation and compared to 5 known short-term retaining slug species and 5 non-retaining slug species. The subsequent results indicate that functional kleptoplasty is not performed by E. timida until after 15 days post-metamorphosis and that by 25 days, these animals outlive many of the short-term retention species. Digestive activity was also monitored using lysosomal abundance as an indicator, revealing different patterns in starving juveniles versus adults. Starved juveniles were reintroduced to food to determine any differences in digestive activity when starvation ends, resulting in an increase in the number of kleptoplasts, but no overall change in lysosomal activity. By revealing some of the changes that occur during early development in these animals, which begin as non-kleptoplast-retaining and grow into long-term retaining slugs, this investigation provides a basis for future inquiries into the origin and development of this remarkable ability.

A national study of the retention of Irish opiate users in methadone substitution treatment

LENUS (Irish Health Repository)

Mullen, Louise

2012-07-02

Background: Retention in treatment is a key indicator of methadone treatment success. The study aims to identify factors that are associated with retention. Objectives: To determine retention in treatment at 12 months for Irish opiate users in methadone substitution treatment and to indicate factors that increase the likelihood of retention. Methods: National cohort study of randomly selected opiate users commencing methadone treatment in 1999, 2001, and 2003 (n = 1269). Results: Sixty-one percent of patients attending methadone treatment remained in continuous treatment for more than 1 year. Retention in treatment at 12 months was associated with age, gender, facility type, and methadone dose. Age and gender were no longer significant when adjusted for other variables in the model. Those who attended a specialist site were twice as likely to leave methadone treatment within 12 months compared with those who attended a primary care physician. The most important predictor of retention in treatment was methadone dose. Those who received <60 mg of methadone were three times more likely to leave treatment. Conclusion: Retention in methadone treatment is high in Ireland in a variety of settings. The main factors influencing retention in methadone treatment was an adequate methadone dose and access to a range of treatment settings including from primary care physicians. Scientific Significance: Providing an adequate dose of methadone during treatment will increase the likelihood of treatment retention. Methadone treatment by the primary care physician is a successful method of retaining opioid users in treatment.

Stellar Wind Retention and Expulsion in Massive Star Clusters

Science.gov (United States)

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

2018-05-01

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

Synthesis and characterization of tissue-retainable methylsulfonyl polychlorinated biphenyl isomers

International Nuclear Information System (INIS)

Haraguchi, K.; Kuroki, H.; Masuda, Y.

1987-01-01

Eighty-six positional isomers of methylsulfonyl polychlorinated biphenyls (MSF-PCBs) have been synthesized by three synthetic routes: (1) the diazo coupling reaction of 3-(methylsulfonyl)chloroaniline with chlorobenzene; (2) nucleophilic substitution of PCB with methanethiolate and successive oxidation of the corresponding methyl sulfide; (3) the diazo coupling reaction of chloroaniline with chlorothioanisole and successive oxidation of the methyl sulfide. Pure isomers were characterized by their proton magnetic resonance and mass spectra and used to unambiguously identify the MSF metabolites retained in human tissues by using high-resolution capillary gas chromatography (GC). The GC analysis showed that 40 MSF derivatives were positively identified in the tissue of a patient with Yusho on the basis of comparisons of their GC retention data with those of the standard compounds

Investigating First Year College Student Locus of Control in Relation to Retention: An Explanatory Mixed Methods Study

Science.gov (United States)

Estes, Aaron

2017-01-01

Institutions of higher education place a high priority on retaining students. With orientation programming, tutoring, learning communities, peer mentoring, and other efforts, institutions dedicate the resources necessary to increase the academic success of their students because academic success has a positive relationship with retention. Through…

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

Science.gov (United States)

Radtke, Christina; Tews, Birke Andrea

2017-10-01

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

Patient preference and satisfaction with implant-supported mandibular overdentures retained with ball or locator attachments: a crossover clinical trial.

Science.gov (United States)

Krennmair, Gerald; Seemann, Rudolf; Fazekas, Andres; Ewers, Rolf; Piehslinger, Eva

2012-01-01

To determine patient satisfaction and preference for implant-supported mandibular overdentures (IOD) retained with ball or Locator attachments. In addition, peri-implant conditions and prosthodontic maintenance efforts for the final attachments were evaluated after 1 year of function. In this crossover clinical trial, 20 edentulous patients were recruited to receive two mandibular implants in the canine region and were provided with implant-retained mandibular overdentures and new complete maxillary dentures. Implant-retained mandibular overdentures were stabilized with either ball attachments or Locator attachments, in random order. After 3 months of function, the attachments in the existing denture were changed. Questionnaires on satisfaction/complaints with the prostheses were administered at baseline (with the old dentures) and after 3 months of function with each attachment, thus providing for an intraindividual comparison. The decision for the final attachment chosen was based on the patient's preference. For the definitive attachment, peri-implant conditions (peri-implant marginal bone resorption, pocket depth, and Plaque Index, Gingival Index, and Bleeding Index) as well as prosthodontic maintenance efforts and satisfaction score were evaluated after an insertion period of 1 year. Nineteen (95%) patients completed the study (1 dropout). Patient satisfaction improved significantly (P<.05) from baseline (old dentures) to the new prostheses retained with each of the two attachment types for all domains of satisfaction. However, there were no differences between ball or Locator attachment for any items of satisfaction evaluated and neither attachment had a significant patient preference. No differences for peri-implant parameters or for patient satisfaction were noted between the definitive attachments (ball, n=10; Locator, n=9) after 1 year. Although the overall incidence rate of prosthodontic maintenance did not significantly differ between both retention

Removal versus retention of cerclage in preterm premature rupture of membranes: a randomized controlled trial.

Science.gov (United States)

Galyean, Anna; Garite, Thomas J; Maurel, Kimberly; Abril, Diana; Adair, Charles D; Browne, Paul; Combs, C Andrew; How, Helen; Iriye, Brian K; Kominiarek, Michelle; Lu, George; Luthy, David; Miller, Hugh; Nageotte, Michael; Ozcan, Tulin; Porto, Manuel; Ramirez, Mildred; Sawai, Shirley; Sorokin, Yoram

2014-10-01

The decision of whether to retain or remove a previously placed cervical cerclage in women who subsequently rupture fetal membranes in a premature gestation is controversial and all studies to date are retrospective. We performed a multicenter randomized controlled trial of removal vs retention of cerclage in these patients to determine whether leaving the cerclage in place prolonged gestation and/or increased the risk of maternal or fetal infection. A prospective randomized multicenter trial of 27 hospitals was performed. Patients included were those with cerclage placement at ≤23 weeks 6 days in singleton or twin pregnancies, with subsequent spontaneous rupture of membranes between 22 weeks 0 days and 32 weeks 6 days. Patients were randomized to retention or removal of cerclage. Patients were then expectantly managed and delivered only for evidence of labor, chorioamnionitis, fetal distress, or other medical or obstetrical indications. Management after 34 weeks was at the clinician's discretion. The initial sample size calculation determined that a total of 142 patients should be included but after a second interim analysis, futility calculations determined that the conditional power for showing statistical significance after randomizing 142 patients for the primary outcome of prolonging pregnancy was 22.8%. Thus the study was terminated after a total of 56 subjects were randomized with complete data available for analysis, 32 to removal and 24 to retention of cerclage. There was no statistical significance in primary outcome of prolonging pregnancy by 1 week comparing the 2 groups (removal 18/32, 56.3%; retention 11/24, 45.8%) P = .59; or chorioamnionitis (removal 8/32, 25.0%; retention 10/24, 41.7%) P = .25, respectively. There was no statistical difference in composite neonatal outcomes (removal 16/33, 50%; retention 17/30, 56%), fetal/neonatal death (removal 4/33, 12%; retention 5/30, 16%); or gestational age at delivery (removal mean 200 days; retention

Retention of external and internal markers by southern pine beetles (Coleoptera: Scolytidae) during gallery

Science.gov (United States)

Douglas J. Rhodes; Jane Leslie Hayes; Chris Steiner

1998-01-01

If retained, markers used in mark-release-recapture studies of bark beetle dispersal could provide valuable tools in the determination of post-dispersal fate. Retention of the internal marker rubidium (Rb) and of the external marker fluorescent powder during egg gallery construction, oviposition, and feeding were quantified at intervals from 0 to 96 hours by allowing...

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

Science.gov (United States)

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

2018-03-01

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

Faculty ratings of retention strategies for minority nursing students.

Science.gov (United States)

Baker, Barbara H

2010-01-01

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

An appraisal of retained placentae in ibadan: a five year review.

Science.gov (United States)

Obajimi, G O; Roberts, A O; Aimakhu, C O; Bello, F A; Olayemi, O

2009-06-01

To determine the frequency of retained placenta at the University College Hospital Ibadan (UCH). and to describe the socio-demographic characteristics of the patients and examine the risk factors predisposing to retained placenta. This is a descriptive study covering a period of 5 years from January 1(st) 2002 to December 31(st) 2006. During the study period, 4980 deliveries took place at the University College Hospital, Ibadan and 106 cases of retained placenta were managed making the incidence 2.13 per cent of all births. During the five year period, there were 106 patients with retained placenta; of these, 90 (84.9%) case notes were available for analysis. The mean age was 29.37 ± 4.99 years. First and second Para accounted for 52 per cent of the patients. Majority of the patient were unbooked for antenatal care in UCH with booked patients accounting for 27.8 per cent of the cases. The mean gestational age at delivery was 34.29 ± 6.02. Three patients presented to the hospital in shock of which 2 died on account of severe haemorrhagic shock. Fifty-eight patients (64.8%) presented with anaemia (packed cell volume less than 30 per cent) and 35 patients (38.8%) had blood transfusion ranging between 1-4 pints. 1 patient required hysterectomy on account of morbidly adherent placenta. Eleven patients (12.2%) had placenta retention in the past, 28 patients (31%) had a previous dilatation and curettage, 14 patients (15.5%) had previous caesarean sections and 47 patients (41.3%) had no known predisposing factors. Retained placenta still remains a potentially life threatening condition in the tropics due to the associated haemorrhage, and other complications related to its removal. The incidence and severity may be decreased by health education, women empowerment and the provision of facilities for essential obstetric services by high skilled health care providers in ensuring a properly conducted delivery with active management of the third stage of labour.

Grade Retention in Primary Education Is Associated with Quarter of Birth and Socioeconomic Status.

Science.gov (United States)

González-Betancor, Sara M; López-Puig, Alexis J

2016-01-01

Grade retention is still common practice in some countries though longstanding experience tells us that it is a highly criticised practice for its unclear benefits, its important costs for the educational systems and its relation with school dropout. Therefore, the aim of the present study is to analyse which variables increase the probability of being retained in primary education differentiating between being retained in second or in fourth grade, and paying special attention to the role of the socioeconomic status of the families. By knowing which analysed variables are related to grade retention, and how, we may offer some suggestions to reduce it. We use a national dataset with more observations for Spain than any other international ones, called 'Evaluación General de Diagnóstico', conducted in Spain in 2009 with the participation of 28708 students of fourth grade of primary education from 874 schools, considered to be representative for every Spanish autonomous region. This assessment focused on four competences and includes information about the learning context collected through questionnaires for students, families, school management and teachers. Estimating different multilevel random-intercept logistic regressions we obtain the following three main findings: 1) the existence of a 'quarter of birth' effect, that nearly doubles the probability of grade retention in second grade of primary -compared to the probability of grade retention in fourth grade-, for the youngest students of their same age cohort (OR = 1.93 vs. OR = 1.53, both peducation level influences more than the fathers' one -especially in second grade (OR = 0.20 vs. OR = 0.45, both p0.05)-.

Inductively coupled plasma mass spectrometry study of the retention behavior of arsenic species on various solid phase extraction cartridges and its application in arsenic speciation

Energy Technology Data Exchange (ETDEWEB)

Yu Chunhai; Cai Qiantao E-mail: qtcai@cawt.sui.com.sg; Guo Zhongxian; Yang Zhaoguang; Khoo, Soo Beng

2003-07-18

Inductively coupled plasma mass spectrometry (ICP-MS) was used to investigate the retention behavior of arsenite, arsenate, monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), arsenobetaine (AsB), arsenocholine (AsC), trimethylarsine oxide (TMAO) and tetramethylarsonium ion (TMAI) on various silica-based solid phase extraction (SPE) cartridges. A method for arsenic speciation is then developed on the basis of selective SPE separation of arsenic species and highly sensitive ICP-MS detection. Factors affecting the retention and elution of arsenic species were examined. Results showed that the retention of arsenic species depended on the chemical characteristics of arsenic species and the types of sorbent materials. Change of pH in the range of 2.0-9.0 did not show significant effects on the retention of DMA, AsB, AsC, TMAI and TMAO on an ethylbenzene sulfonic acid-based strong cation exchange (SCX-3) cartridge. pH also did not influence the retention of AsB, AsC, TMAI and TMAO on a mixed-mode (M-M) cartridge containing non-polar, strong cation exchange and strong anion exchange (SAX) functional groups. However, the retentions of As(V) and MMA on the SAX and the M-M cartridge changed with pH. As(V) and MMA were completely retained on the SAX cartridge and sequentially selectively eluted with 1.0 mol l{sup -1} acetic acid (for MMA). DMA, AsB, AsC, TMAI and TMAO were completely retained on the SCX-3 cartridge and sequentially selectively eluted with 1.0 mol l{sup -1} HNO{sub 3} (for DMA). As(V), MMA, AsB, AsC, TMAI and TMAO were completely retained on the M-M cartridge. As(III) was not retained on either cartridge and remained in solution. Arsenic species in solution and those eluted from the cartridges were subsequently determined by ICP-MS. A detection limit of 8 ng l{sup -1} arsenic in water sample was obtained. This method was successfully applied to arsenic speciation in various sources of water samples (drinking water, waste water, raw water, etc.) and US

Study of deuterium retention in/release from ITER-relevant Be-containing mixed material layers implanted at elevated temperatures

Energy Technology Data Exchange (ETDEWEB)

Sugiyama, K., E-mail: kazuyoshi.sugiyama@ipp.mpg.de [Max-Planck-Institut für Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Porosnicu, C. [National Institute for Laser, Plasma and Radiation Physics, EURATOM-MEdC Association, 077125 Bucharest (Romania); Jacob, W.; Roth, J.; Dürbeck, Th. [Max-Planck-Institut für Plasmaphysik, EURATOM Association, D-85748 Garching (Germany); Jepu, I.; Lungu, C.P. [National Institute for Laser, Plasma and Radiation Physics, EURATOM-MEdC Association, 077125 Bucharest (Romania)

2013-07-15

D implantation into Be-containing mixed material layers: Be, Be–W (W: ∼6 at.%) and Be–C (C: ∼50 at.%), was performed at elevated temperatures. The temperature dependence of D retention varied depending on the admixed element. D retention in Be and Be–W layers decreases with increasing implantation temperature, while the Be–C layers maintained rather high D retention in the present investigated temperature range (up to 623 K). D desorption behaviour from Be–C suggests the contribution of C–D bonds to D retention. W admixture into Be can significantly suppress D retention in Be. Long-term isothermal annealing at 513 and 623 K for D removal was also performed to simulate the ITER-wall-baking scenario. Even extended annealing at temperatures comparable to or lower than the implantation temperature does not lead to a significant release of retained D.

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

Energy Technology Data Exchange (ETDEWEB)

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

1997-09-01

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

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

International Nuclear Information System (INIS)

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

1997-09-01

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

Retention of key employees in the oil field service sector

International Nuclear Information System (INIS)

Lee, S.

1999-01-01

Before 1994, Core Laboratories Canada Ltd. adopted local country benefit plans as stipulated by the government of the day. This approach meant that the company had many different benefit plans in place or in some situations no benefit plans at all, if the law of the land allowed such an approach. The company at this time viewed the lack of or minimal benefit plans as a cost saving venture. The parent company did not take onto account the effect on morale, employee retention and loyalty that these limited plans provided. A change in ownership in 1994 presented the opportunity for Core to re-assess its benefits package and introduce an incentive plan for its worldwide employees. The introduction of a pension with profits plan proved to be satisfying to employees, and the manager's incentive plan enabled the company to retain, with the exception of people who retired from the business, its entire management staff over a four year period. The stock option plan led to the retention of essential employees and reduced the turnover in this area. Discretionary bonuses succeeded in promoting recognition amongst employees as well as providing monetary reward, and the combination of benefits, incentive and stock option plans enabled the company to retain the vast majority of key employees and to entice selected individuals to the company from other organizations. 3 refs

Retention of metal-ceramic crowns with contemporary dental cements.

Science.gov (United States)

Johnson, Glen H; Lepe, Xavier; Zhang, Hai; Wataha, John C

2009-09-01

New types of crown and bridge cement are in use by practitioners, and independent studies are needed to assess their effectiveness. The authors conducted a study in three parts (study A, study B, and study C) and to determine how well these new cements retain metal-ceramic crowns. The authors prepared teeth with a 20-degree taper and a 4-millimeter length. They cast high-noble metal-ceramic copings, then fitted and cemented them with a force of 196 newtons. The types of cements they used were zinc phosphate, resin-modified glass ionomer, conventional resin and self-adhesive modified resin. They thermally cycled the cemented copings, then removed them. They recorded the removal force and calculated the stress of dislodgment by using the surface area of each preparation. They used a single-factor analysis of variance to analyze the data (alpha = .05). The mean stresses necessary to remove crowns, in megapascals, were 8.0 for RelyX Luting (3M ESPE, St. Paul, Minn.), 7.3 for RelyX Unicem (3M ESPE), 5.7 for Panavia F (Kuraray America, New York) and 4.0 for Fuji Plus (GC America, Alsip, Ill.) in study A; 8.1 for RelyX Luting, 2.6 for RelyX Luting Plus (3M ESPE) and 2.8 for Fuji CEM (GC America) in study B; and 4.9 for Maxcem (Kerr, Orange, Calif.), 4.0 for BisCem (Bisco, Schaumburg, Ill.), 3.7 for RelyX Unicem Clicker (3M ESPE), 2.9 for iCEM (Heraeus Kulzer, Armonk, N.Y.) and 2.3 for Fleck's Zinc Cement (Keystone Industries, Cherry Hill, N.J.) in study C. Powder-liquid versions of new cements were significantly more retentive than were paste-paste versions of the same cements. The mean value of crown removal stress for the new self-adhesive modified-resin cements varied appreciably among the four cements tested. All cements retained castings as well as or better than did zinc phosphate cement. Powder-liquid versions of cements, although less convenient to mix, may be a better clinical choice when crown retention is an issue. All cements tested will retain castings

Metabolic and mineral conditions of retained placenta in highly productive dairy cows: pathogenesis, diagnostics and prevention – a review

Directory of Open Access Journals (Sweden)

Ryszard Mordak

2017-01-01

Full Text Available The time around calving in highly productive dairy cows is a critical period in terms of their metabolism, which is connected with high demands of the foetus as well as with the onset of lactation. Retained placenta in cows may have multifactorial aetiology, but in herds which are free from infectious diseases, the most important reasons are; periparturient metabolic changes and disturbances to the internal balance and stress. During the periparturient period, the most important factor causing immune suppression and hypotony of uterus in cows is metabolic stress due to hormonal and nutritional factors, including metabolic fluctuations, negative energy balance, as well as shortage of proteins, minerals, vitamins and antioxidants. This metabolic stress as a result of an imbalance in the internal metabolic homeostasis activates the hypothalamic-pituitary-adrenocortical axis (HPA and increases serum corticosterid (cortisol concentration, especially on the day of calving. Cortisol is a powerful immune suppressive factor that causes depression of leukocyte proliferation and their functions. The periparturient metabolic stress may also stimulate the production of catecholamines, especially adrenalin. Elevated levels of adrenalin activate adrenoreceptors of the myometrium, which in turn cause hypotony or atony of the uterus at calving in cows. Elevated levels of cortisol and adrenalin may significantly inhibit the rejection and expulsion of foetal membranes in cows, resulting in an increased incidence of their retention. These important mechanisms for placental retention in highly productive dairy cows often have primary nutritional metabolic aetiology, but they also occur during secondary metabolic disturbances and metabolic stress during calving. This metabolic and immunological aetiology and pathogenesis of retained placenta usually occur in highly productive periparturient cows on dairy farms in the absence of bovine infectious diseases, which can

Acute urinary retention as a late complication of subcutaneous liquid silicone injection: a case report

Directory of Open Access Journals (Sweden)

Leandro Luongo de Matos

2009-12-01

Full Text Available Acute urinary retention is characterized by a sudden interruption of urinary output; urine is retained in the bladder due to either functional or obstructive anatomic factors, and cannot be voided. The main causes of acute urinary obstruction are benign prostatic hyperplasia, constipation, prostate adenocarcinoma, urethral stenosis, clot retention, neurological disorders, following surgery, calculi, drugs, or urinary tract infections. A transvestite patient, aged 55 years, described having had liquid silicone subcutaneously injected in various parts of the body, the last one four years ago. He complained of absent urinary output during the last 14 hours. The physical examination revealed skin deformation due to migration of implants; a hard nodule (characterized as a foreign body was present in the preputium and a diagnosis of acute urinary retention was made; an unsuccessful attempt to exteriorize the glans for urinary catheterization, was followed by therapeutic cystostomy. Acute urinary retention has not been mentioned in the medical literature as a complication of liquid silicone subcutaneous injection.

Effects of starvation and protein depletion on mercury retention in two strains of chickens

Energy Technology Data Exchange (ETDEWEB)

Larkin, D V; Miller, V L; Bearse, G E; Hamilton, C M

1965-11-13

Experiments were performed in an attempt to show the effects of deprivation of feed and water on the liver and kidney mercury retention in two strains of chickens. The chickens to be depleted were fasted for 24 h and offered granulated sugar and drinking water containing vitamins. When the protein-depleted chickens has lost 30% of their body weight, they were injected intramuscularly with 3 mg phenylmercuric acetate (PMA) or mercuric chloride. A chemical analysis of the livers and kidneys of the chickens revealed that more mercury was retained in the organs from the protein-depleted chickens than from the control chickens. A difference was also found in the mercury retention in the kidneys in the two strains of chickens. Thus, alteration of the mercury retention patterns of these two strains of chickens may be accomplished by limiting their protein intake.

Length of Service versus Employee Retention Factors: Hotels in Cape Town, South Africa

Directory of Open Access Journals (Sweden)

Ikechukwu O. Ezeuduji

2017-04-01

Full Text Available Employee retention can be measured quite accurately by the actual number of years that employees have worked in an organisation. This study investigates relationships between hotel employees’ length of service and responses to individual variables explaining employee retention factors. A structured questionnaire survey of 217 hotel employees in Cape Town, South Africa was used to obtain information that were subjected to bivariate and multivariate analyses. Key results show that the employees who have worked longer in the hotel have particular characteristics: they perceive that working hours in the hotel do not infringe on their personal quality time with friends; they perceive it will be difficult for them to leave the hotel; they want to remain in the hotel for a long time; and quite interestingly, they perceive they do not receive continuous training in the hotel. Further costs of hiring and developing new employees can be reduced if loyal and talented employees are retained for longer periods through continuous career development. This study is of particular interest to the hotel sector management, as it is focussed on retaining those staff who really want to build a career in the hospitality industry.

Effect of different surface treatments and retainer designs on the retention of posterior Pd-Ag porcelain-fused-to-metal resin-bonded fixed partial dentures.

Science.gov (United States)

Chen, Xiwen; Zhang, Yixin; Zhou, Jinru; Chen, Chenfeng; Zhu, Zhimin; Li, Lei

2018-02-01

The aim of this study was to investigate the adhesive property of palladium-silver alloy (Pd-Ag) and the simulated clinical performance of Pd-Ag porcelain-fused-to-metal (PFM), resin-bonded, fixed partial dentures (RBFPDs). A total of 40 Pd-Ag discs (diameter=5 mm) were prepared and divided into the following four groups (n=10): a) No sandblasting, used as a control; and b, 50 µm; c, 110 µm; and d, 250 µm aluminum oxide (Al 2 O 3 ) particles, respectively. Another 50 discs were pre-sandblasted and divided into five groups (n=10) subjected to different treatments: e) Sandblasting, used as a control; f) silane; g) alloy primer; h) silica coating + silane and i) silica coating + alloy primer. All 90 discs were bonded to enamel with Panavia F 2.0 and then subjected to shear bond strength (SBS) testing. The fracture surfaces were examined by scanning electron microscopy. Next, 40 missing maxillary second premolar models were restored with one of the four following RBFPD designs (n=10): I) A premolar occlusal bar combined with molar double rests (MDR); II) both occlusal bars with a wing (OBB); III) a premolar occlusal bar combined with a molar dental band (MDB); and IV) two single rests adjacent to the edentulous space with a wing (SRB) used as a control. All specimens were aged with thermal cycling and mechanical loading. Subsequently, they were loaded until broken. The data were analyzed by one-way analysis of variance. Al 2 O 3 (250 µm) abrasion provided the highest SBS (P<0.05). The alloy primer and silica + silane exhibited increased SBS. Furthermore, fracture analysis revealed that the failure mode varied among the different treatments. Whereas MDB exhibited the highest retention (P<0.05), that of OBB was greater than that of MDR (P<0.05), and the control exhibited the lowest retention. Abrasion with Al 2 O 3 (250 µm) effectively increased the adhesive property of Pd-Ag. Additionally, treatment with the alloy primer and silica coating + silane was able to

Retention in buprenorphine treatment is associated with improved HCV care outcomes.

Science.gov (United States)

Norton, B L; Beitin, A; Glenn, M; DeLuca, J; Litwin, A H; Cunningham, C O

2017-04-01

Persons who inject drugs, most of whom are opioid dependent, comprise the majority of the HCV infected in the United States. As the national opioid epidemic unfolds, increasing numbers of people are entering the medical system to access treatment for opioid use disorder, specifically with buprenorphine. Yet little is known about HCV care in patients accessing buprenorphine-based opioid treatment. We sought to determine the HCV prevalence, cascade of care, and the association between patient characteristics and completion of HCV cascade of care milestones for patients initiating buprenorphine treatment. We reviewed electronic health records of all patients who initiated buprenorphine treatment at a primary-care clinic in the Bronx, NY between January 2009 and January 2014. Of the 390 patients who initiated buprenorphine treatment, 123 were confirmed to have chronic HCV infection. The only patient characteristic associated with achieving HCV care milestones was retention in opioid treatment. Patients retained (vs. not retained) in buprenorphine treatment were more likely to be referred for HCV specialty care (63.1% vs. 34.0%, p<0.01), achieve an HCV-specific evaluation (40.8% vs. 21.3%, p<0.05), be offered HCV treatment (22.4% vs. 8.5%, p<0.05), and initiate HCV treatment (9.2% vs. 6.4%, p=0.6). Given the current opioid epidemic in the US and the growing number of people receiving buprenorphine treatment, there is an unprecedented opportunity to access and treat persons with HCV, reducing HCV transmission, morbidity and mortality. Retention in opioid treatment may improve linkage and retention in HCV care; innovative models of care that integrate opioid drug treatment with HCV treatment are essential. Copyright © 2017 Elsevier Inc. All rights reserved.

The Use of Gadolinium-Carbon Nanostructures to Magnetically Enhance Stem Cell Retention for Cellular Cardiomyoplasty

Science.gov (United States)

Tran, Lesa A.; Hernández-Rivera, Mayra; Berlin, Ari N.; Zheng, Yi; Sampaio, Luiz; Bové, Christina; Cabreira-Hansen, Maria da Graça; Willerson, James T.; Perin, Emerson C.; Wilson, Lon J.

2014-01-01

In this work, the effectiveness of using Gadonanotubes (GNTs) with an external magnetic field to improve retention of transplanted adult mesenchymal stem cells (MSCs) during cellular cardiomyoplasty was evaluated. As a high-performance T1-weighted magnetic resonance imaging (MRI) cell tracking label, the GNTs are gadolinium-loaded carbon nanotube capsules that render MSCs magnetic when internalized. MSCs were internally labeled with either superparamagnetic GNTs or colloidal diamagnetic lutetium (Lu). In vitro cell rolling assays and ex vivo cardiac perfusion experiments qualitatively demonstrated increased magnetic-assisted retention of GNT-labeled MSCs. Subsequent in vivo epicardial cell injections were performed around a 1.3 T NdFeB ring magnet sutured onto the left ventricle of female juvenile pigs (n = 21). Cell dosage, magnet exposure time, and endpoints were varied to evaluate the safety and efficacy of the proposed therapy. Quantification of retained cells in collected tissues by elemental analysis (Gd or Lu) showed that the external magnet helped retain nearly three times more GNT-labeled MSCs than Lu-labeled cells. The sutured magnet was tolerated for up to 168 hours; however, an inflammatory response to the magnet was noted after 48 hours. These proof-of-concept studies support the feasibility and value of using GNTs as a magnetic nanoparticle facilitator to improve cell retention during cellular cardiomyoplasty. PMID:24148239

The use of gadolinium-carbon nanostructures to magnetically enhance stem cell retention for cellular cardiomyoplasty.

Science.gov (United States)

Tran, Lesa A; Hernández-Rivera, Mayra; Berlin, Ari N; Zheng, Yi; Sampaio, Luiz; Bové, Christina; Cabreira-Hansen, Maria da Graça; Willerson, James T; Perin, Emerson C; Wilson, Lon J

2014-01-01

In this work, the effectiveness of using Gadonanotubes (GNTs) with an external magnetic field to improve retention of transplanted adult mesenchymal stem cells (MSCs) during cellular cardiomyoplasty was evaluated. As a high-performance T1-weighted magnetic resonance imaging (MRI) cell tracking label, the GNTs are gadolinium-loaded carbon nanotube capsules that render MSCs magnetic when internalized. MSCs were internally labeled with either superparamagnetic GNTs or colloidal diamagnetic lutetium (Lu). In vitro cell rolling assays and ex vivo cardiac perfusion experiments qualitatively demonstrated increased magnetic-assisted retention of GNT-labeled MSCs. Subsequent in vivo epicardial cell injections were performed around a 1.3 T NdFeB ring magnet sutured onto the left ventricle of female juvenile pigs (n = 21). Cell dosage, magnet exposure time, and endpoints were varied to evaluate the safety and efficacy of the proposed therapy. Quantification of retained cells in collected tissues by elemental analysis (Gd or Lu) showed that the external magnet helped retain nearly three times more GNT-labeled MSCs than Lu-labeled cells. The sutured magnet was tolerated for up to 168 h; however, an inflammatory response to the magnet was noted after 48 h. These proof-of-concept studies support the feasibility and value of using GNTs as a magnetic nanoparticle facilitator to improve cell retention during cellular cardiomyoplasty. Copyright © 2013 Elsevier Ltd. All rights reserved.

NERVA turbopump bearing retainer fabrication on nonmetallic retainer

Science.gov (United States)

Accinelli, J. B.

1972-01-01

The need for a low-wear, lightweight, high strength bearing retainer material with a radiation degradation threshold of 10 to the 9th power rads (C) prompted development of nonmetallic reinforced polymers of the following types: (1) polybenzimidazole, (2) polyimide, and (3) polyquinoxaline. Retainers were machined from tubular laminates (billets), including reinforcement by either glass or graphite fabric or filament. Fabrication of billets involves hot preimpregnation of the reinforcement fabric or filament with polymer followed by wrapping this prepreg over a heated mandrel to form a tube with the required thickness and length.

Long-term impacts of variable retention harvesting on ground-layer plant communities in Pinus resinosa forests

Science.gov (United States)

Margaret W. Roberts; Anthony W. D' Amato; Christel C. Kern; Brian J. Palik; Lorenzo Marini

2016-01-01

Concerns about loss of biodiversity and structural complexity in managed forests have recently increased and led to the development of new management strategies focused on restoring or maintaining ecosystem functions while also providing wood outputs. Variable retention harvest (VRH) systems, in which mature overstorey trees are retained in various spatial arrangements...

Retention of actinides and rare earth in the alteration gels of R7T7 nuclear glass

International Nuclear Information System (INIS)

Advocat, Th.; Menard, O.; Chouchan, J.L.; Jollivet, P.

1997-01-01

Under oxic conditions, over 98.5% of the lanthanides and thorium released from the glass were retained in the alteration products on the glass surface, probably by coprecipitation with a siliceous gel. Uranium and Neptunium retention varied from 40% in carbonated medium to more than 95% in phosphate medium. With carbonate ions, Np and U formed stable complexes, which tend to limit actinide incorporation in the gel layer. Plutonium retention is larger than 90%. This element exhibited atypical behaviour to the extend that it was strongly bonded to colloidal particles in solution. (authors)

Retention of Halogens in Waste Glass

Energy Technology Data Exchange (ETDEWEB)

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.

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

International Nuclear Information System (INIS)

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

1998-09-01

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

Recruiting and retaining family caregivers to a randomized controlled trial on mindfulness-based stress reduction.

Science.gov (United States)

Whitebird, Robin R; Kreitzer, Mary Jo; Lewis, Beth A; Hanson, Leah R; Crain, A Lauren; Enstad, Chris J; Mehta, Adele

2011-09-01

Caregivers for a family member with dementia experience chronic long-term stress that may benefit from new complementary therapies such as mindfulness-based stress reduction. Little is known however, about the challenges of recruiting and retaining family caregivers to research on mind-body based complementary therapies. Our pilot study is the first of its kind to successfully recruit caregivers for a family member with dementia to a randomized controlled pilot study of mindfulness-based stress reduction. The study used an array of recruitment strategies and techniques that were tailored to fit the unique features of our recruitment sources and employed retention strategies that placed high value on establishing early and ongoing communication with potential participants. Innovative recruitment methods including conducting outreach to health plan members and generating press coverage were combined with standard methods of community outreach and paid advertising. We were successful in exceeding our recruitment goal and retained 92% of the study participants at post-intervention (2 months) and 90% at 6 months. Recruitment and retention for family caregiver interventions employing mind-body based complementary therapies can be successful despite many challenges. Barriers include cultural perceptions about the use and benefit of complementary therapies, cultural differences with how the role of family caregiver is perceived, the use of group-based designs requiring significant time commitment by participants, and travel and respite care needs for busy family caregivers. Copyright © 2011 Elsevier Inc. All rights reserved.

Ever Since the World Began: A Reading & Interview with Masha Tupitsyn

OpenAIRE

Masha Tupitsyn

2013-01-01

Writer and cultural critic Masha Tupitsyn is interviewed on her audio recording of her reading Ever Since This World Began, produced specially for this issue of continent. and adapted from her recently published Love Dog (Success and Failure) out from Penny-Ante Editions.

Ignalina RBMK-1500 building capability in retaining radioactive releases

International Nuclear Information System (INIS)

Nilsson, Lars; Johansson, K.

1993-01-01

The Ignalina reactor building structures are capable of retaining substantial fractions of radioactive emissions from the fuel core, in those accident sequences where pressurization failure of structures can be averted by pressure relief arrangements. In stage 1 of the IBBA project it was demonstrated that enhanced retention of radioactive fission products within the plant can be achieved if natural convection is facilitated in the upper building compartments. In this report of stage 2 is discussed for which accident sequences the introduction of natural convection in combination with the existing forced convection ventilation and the accident localization system can improve the total safety of Ignalina 1-2. The purpose of this stage is to provide a basis for further review and more detailed studies of the natural convection concept, its benefits and disadvantages, and of the feasability to introduce the concept in existing plants

Addressing the crisis of GP recruitment and retention: a systematic review.

Science.gov (United States)

Marchand, Catherine; Peckham, Stephen

2017-04-01

The numbers of GPs and training places in general practice are declining, and retaining GPs in their practices is an increasing problem. To identify evidence on different approaches to retention and recruitment of GPs, such as intrinsic versus extrinsic motivational determinants. Synthesis of qualitative and quantitative research using seven electronic databases from 1990 onwards (Medline, Embase, Cochrane Library, Health Management Information Consortium [HMIC], Cumulative Index to Nursing and Allied Health Literature (Cinahl), PsycINFO, and the Turning Research Into Practice [TRIP] database). A qualitative approach to reviewing the literature on recruitment and retention of GPs was used. The studies included were English-language studies from Organisation for Economic Cooperation and Development countries. The titles and abstracts of 138 articles were reviewed and analysed by the research team. Some of the most important determinants to increase recruitment in primary care were early exposure to primary care practice, the fit between skills and attributes, and a significant experience in a primary care setting. Factors that seemed to influence retention were subspecialisation and portfolio careers, and job satisfaction. The most important determinants of recruitment and retention were intrinsic and idiosyncratic factors, such as recognition, rather than extrinsic factors, such as income. Although the published evidence relating to GP recruitment and retention is limited, and most focused on attracting GPs to rural areas, the authors found that there are clear overlaps between strategies to increase recruitment and retention. Indeed, the most influential factors are idiosyncratic and intrinsic to the individuals. © British Journal of General Practice 2017.

Postpartum Engagement in HIV Care: An Important Predictor of Long-term Retention in Care and Viral Suppression.

Science.gov (United States)

Adams, Joëlla W; Brady, Kathleen A; Michael, Yvonne L; Yehia, Baligh R; Momplaisir, Florence M

2015-12-15

Human immunodeficiency virus (HIV)-infected women are at risk of virologic failure postpartum. We evaluated factors influencing retention in care and viral suppression in postpartum HIV-infected women. We conducted a retrospective cohort analysis (2005-2011) of 695 deliveries involving 561 HIV-infected women in Philadelphia. Multivariable logistic regression evaluated factors, including maternal age, race/ethnicity, substance use, antiretroviral therapy during pregnancy, timing of HIV diagnosis, previous pregnancy with HIV, adequacy of prenatal care, and postpartum HIV care engagement (≥ 1 CD4 count or viral load [VL] test within 90 days of delivery), associated with retention in care (≥ 1 CD4 count or VL test in each 6-month interval of the period with ≥ 60 days between tests) and viral suppression (VL ≤ 200 copies/mL at the last measure in the period) at 1 and 2 years postpartum. Overall, 38% of women engaged in HIV care within 90 days postpartum; with 39% and 31% retained in care and virally suppressed, respectively, at 1 year postpartum, and 25% and 34% retained in care and virally suppressed, respectively, at 2 years postpartum. In multivariable analyses, women who engaged in HIV care within 90 days of delivery were more likely to be retained (adjusted odds ratio [AOR], 11.38; 95% confidence interval [CI], 7.74-16.68) and suppressed (AOR, 2.60 [95% CI, 1.82-3.73]) at 1 year postpartum. This association persisted in the second year postpartum for both retention (AOR, 6.19 [95% CI, 4.04-9.50]) and suppression (AOR, 1.40 [95% CI, 1.01-1.95]). The prevalence of postpartum HIV-infected women retained in care and maintaining viral suppression is low. Interventions seeking to engage women in care shortly after delivery have the potential to improve clinical outcomes. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Peripheral arterial vasodilation hypothesis: a proposal for the initiation of renal sodium and water retention in cirrhosis

DEFF Research Database (Denmark)

Schrier, R W; Arroyo, V; Bernardi, M

1988-01-01

Renal sodium and water retention and plasma volume expansion have been shown to precede ascites formation in experimental cirrhosis. The classical "underfilling" theory, in which ascites formation causes hypovolemia and initiates secondary renal sodium and water retention, thus seems unlikely...... with cirrhosis. Arterial vasodilators and arteriovenous fistula are other examples in which renal sodium and water retention occur secondary to a decreased filling of the arterial vascular tree. An increase in cardiac output and hormonal stimulation are common features of cirrhosis, arteriovenous fistula...... and drug-induced peripheral arterial vasodilation. However, a predilection for the retained sodium and water to transudate into the abdominal cavity occurs with cirrhosis because of the presence of portal hypertension. The Peripheral Arterial Vasodilation Hypothesis also explains the continuum from...

NOx retention in scrubbing column

International Nuclear Information System (INIS)

Nakazone, A.K.; Costa, R.E.; Lobao, A.S.T.; Matsuda, H.T.; Araujo, B.F.

1988-07-01

During the UO 2 dissolution in nitric acid, some different species of NO x are released. The off gas can either be refluxed to the dissolver or be released and retained on special columns. The final composition of the solution is the main parameter to take in account. A process for nitrous gases retention using scubber columns containing H 2 O or diluted HNO 3 is presented. Chemiluminescence measurement was employed to NO x evalution before and after scrubbing. Gas flow, temperature, residence time are the main parameters considered in this paper. For the dissolution of 100g UO 2 in 8M nitric acid, a 6NL/h O 2 flow was the best condition for the NO/NO 2 oxidation with maximum adsorption in the scrubber columns. (author) [pt

7 CFR 1767.25 - Retained earnings.

Science.gov (United States)

2010-01-01

... 7 Agriculture 12 2010-01-01 2010-01-01 false Retained earnings. 1767.25 Section 1767.25....25 Retained earnings. The retained earnings accounts identified in this section shall be used by all RUS borrowers. Retained Earnings 433-439 [Reserved] Retained Earnings 433-439 [Reserved] ...

Modeling the retention of rumen boluses for the electronic identification of goats.

Science.gov (United States)

Carné, S; Caja, G; Ghirardi, J J; Salama, A A K

2011-02-01

We constructed a regression model to estimate the retention of electronic boluses in goats. With this aim, 2,482 boluses were administered to goats from dairy (Murciano-Granadina, n=1,326; French Alpine, n=381) and meat (Blanca de Rasquera, n=532) breeds. A total of 19 bolus types made of materials (ceramic, plastic tubes filled with concrete or silicone, and ballasts) differing in their specific gravity (SG) were used, thereby obtaining a wide variation in bolus features: diameter (9 to 22 mm), length (37 to 84 mm), weight (5 to 111 g), volume (2.6 to 26 mL), and SG (1.0 to 5.5). Each bolus contained a half-duplex glass encapsulated transponder (32 × 3.8mm) and was administered using adapted balling guns. Murciano-Granadina and Blanca de Rasquera goats also wore 2 visual plastic ear tags: V1 (double flag, 5.1g) and V2 (flag-button, 4.2g). No data on ear tags in French Alpine goats was available. Bolus and ear tag retention [(retained/monitored) × 100] was recorded for at least 1 yr. Dynamic reading efficiency [(dynamic reading/static reading) × 100] was also evaluated from 1,496 bolus readings. No administration incidences or apparent negative behavior or performance effects were observed for any bolus type. Static reading efficiency of retained boluses was 100%, except for the prototypes with metal ballasts, which yielded a 93.3% reading efficiency. Retention of metal-ballasted boluses was confirmed using x-ray equipment. Excluding ballasted boluses, a 99.5% dynamic reading efficiency was obtained. Ear tag losses were 6.5% for V1 and 3.7% for V2, ranging from 3.2 to 7.8% depending on ear tag type and goat breed. Bolus retention varied (0 to 100%) according to their physical features. Obtained data allowed the fitting of a logistic model of bolus retention rate according to bolus volume and weight (R(2) = 0.98); the SG was implicitly considered. Estimated weight and SG to produce medium- (15 mL) and standard-sized (22 mL) boluses for 99.95% retention rate in

Ever Since the World Began: A Reading & Interview with Masha Tupitsyn

Directory of Open Access Journals (Sweden)

Masha Tupitsyn

2013-07-01

Full Text Available Writer and cultural critic Masha Tupitsyn is interviewed on her audio recording of her reading Ever Since This World Began, produced specially for this issue of continent. and adapted from her recently published Love Dog (Success and Failure out from Penny-Ante Editions.

Sleep confers a benefit for retention of statistical language learning in 6.5month old infants.

Science.gov (United States)

Simon, Katharine N S; Werchan, Denise; Goldstein, Michael R; Sweeney, Lucia; Bootzin, Richard R; Nadel, Lynn; Gómez, Rebecca L

2017-04-01

Infants show robust ability to track transitional probabilities within language and can use this information to extract words from continuous speech. The degree to which infants remember these words across a delay is unknown. Given well-established benefits of sleep on long-term memory retention in adults, we examine whether sleep similarly facilitates memory in 6.5month olds. Infants listened to an artificial language for 7minutes, followed by a period of sleep or wakefulness. After a time-matched delay for sleep and wakefulness dyads, we measured retention using the head-turn-preference procedure. Infants who slept retained memory for the extracted words that was prone to interference during the test. Infants who remained awake showed no retention. Within the nap group, retention correlated with three electrophysiological measures (1) absolute theta across the brain, (2) absolute alpha across the brain, and (3) greater fronto-central slow wave activity (SWA). Copyright © 2016 Elsevier Inc. All rights reserved.

Effect of polymers on the retention and aging of enzyme on bioactive papers.

Science.gov (United States)

Khan, Mohidus Samad; Haniffa, Sharon B M; Slater, Alison; Garnier, Gil

2010-08-01

The effect of polymer on the retention and the thermal stability of bioactive enzymatic papers was measured using a colorimetric technique quantifying the intensity of the enzyme-substrate product complex. Alkaline phosphatase (ALP) was used as model enzyme. Three water soluble polymers: a cationic polyacrylamide (CPAM), an anionic polyacrylic acid (PAA) and a neutral polyethylene oxide (PEO) were selected as retention aids. The model polymers increased the enzyme adsorption on paper by around 50% and prevented enzyme desorption upon rewetting of the papers. The thermal deactivation of ALP retained on paper with polymers follows two sequential first order reactions. This was also observed for ALP simply physisorbed on paper. The retention aid polymers instigated a rapid initial deactivation which significantly decreased the longevity of the enzymatic papers. This suggests some enzyme-polymer interaction probably affecting the enzyme tertiary structure. A deactivation mathematical model predicting the enzymatic paper half-life was developed. Crown Copyright 2010. Published by Elsevier B.V. All rights reserved.

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

Science.gov (United States)

Rosen, Sydney; Fox, Matthew P.

2011-01-01

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

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

Science.gov (United States)

Zatorre, R J; Beckett, C

1989-09-01

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

Postpartum weight retention and breastfeeding among obese women from the randomized controlled Lifestyle in Pregnancy (LiP) trial

DEFF Research Database (Denmark)

Vinter, Christina Anne; Jensen, Dorte Møller; Ovesen, Per Glud

2014-01-01

OBJECTIVES: To study the effects of lifestyle intervention in pregnancy on weight retention 6 months postpartum among obese women from the "Lifestyle in Pregnancy" (LiP) study, and to determine associations between breastfeeding with postpartum maternal weight. DESIGN: Six months postpartum follow...... routine pregnancy care. Both groups received standard postnatal care. MAIN OUTCOME MEASURES: Gestational weight gain, postpartum weight retention and breastfeeding. RESULTS: Follow up was completed in 238 women of whom 46% in the intervention group and 57% in the control group had retained weight 6 months...

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

Directory of Open Access Journals (Sweden)

Angel Alvarez-Arenal

2016-01-01

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

Enhanced retention of a maxillofacial prosthetic obturator using precision attachments: Two case reports

OpenAIRE

Murat, Sema; Gurbuz, Ayhan; Isayev, Abulfaz; Dokmez, Bahadir; Cetin, Unsun

2012-01-01

The majority of maxillary defects can be rehabilitated with conventional simple obturator prosthesis. However, inadequate retention, stability and support may be associated with the use of an obturator. Precision attachments have been used to retain obturators for some time. The use of precision attachments in a dentate maxillectomy patient can yield significant functional improvement while maintaining the obturator’s aesthetic advantages. This clinical report describes the prosthetic rehabil...

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

Energy Technology Data Exchange (ETDEWEB)

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

2017-09-01

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

Whole-body retention of 60Co incorporated into a seaweed in rats

International Nuclear Information System (INIS)

Inaba, Jiro; Nishimura, Yoshikazu; Ichikawa, Ryushi

1979-01-01

The objective of this study is to compare whole-body retention in the rat of radiocobalt incorporated into a marine green alga with that of 60 Co in inorganic form. Ulva pertusa was incubated in aerated seawater containing 60 Co under fluorescent lamp for 7 days. The radioactive seaweed was homogenated and was given to rats via a stomach tube. The control group of rats was given 60 CoCl 2 with homogenate of non-radioactive seaweed. Whole-body retention of the radionuclide was determined by in vivo counting of the living animal. The result revealed that rats absorbed and retained much more 60 Co incorporated into the seaweed than 60 CoCl 2 . This fact should be taken into account in the estimation of internal dose due to radiocobalt released into marine environment. (author)

The aging nursing workforce: How to retain experienced nurses.

Science.gov (United States)

Cohen, Jeremye D

2006-01-01

In the face of an anticipated nursing shortage, healthcare organizations must evaluate their culture, operations, and compensation system to ensure that these elements align with organizational efforts to retain nurses who are approaching retirement age. Management should focus on enhancing elements of job satisfaction and job embeddedness that will motivate nurses to remain both in the workforce and with their employer. Although much of this responsibility falls on the nurse manager, nurse managers are often not provided the necessary support by top management and are neither recognized nor held accountable for nurse turnover. Other retention initiatives can include altering working conditions to reduce both physical and mental stress and addressing issues of employee health and safety. As for compensation, organizations may be well-served by offering senior nursing staff flexible working hours, salary structures that reward experience, and benefit programs that hold value for an aging workforce.

Urinary Analysis of Fluid Retention in the General Population: A Cross-Sectional Study.

Directory of Open Access Journals (Sweden)

Robert G Hahn

Full Text Available Renal conservation (retention of fluid might affect the outcome of hospital care and can be indicated by increased urinary concentrations of metabolic waste products. We obtained a reference material for further studies by exploring the prevalence of fluid retention in a healthy population.Spot urine sampling was performed in 300 healthy hospital workers. A previously validated algorithm summarized the urine-specific gravity, osmolality, creatinine, and color to a fluid retention index (FRI, where 4.0 is the cut-off for fluid retention consistent with dehydration. In 50 of the volunteers, we also studied the relationships between FRI, plasma osmolality, and water-retaining hormones.The cut-off for fluid retention (FRI ≥ 4.0 was reached by 38% of the population. No correlation was found between the FRI and the time of the day of urine sample collection, and the FRI was only marginally correlated with the time period spent without fluid intake. Volunteers with fluid retention were younger, generally men, and more often had albuminuria (88% vs. 34%, P < 0.001. Plasma osmolality and plasma sodium were somewhat higher in those with a high FRI (mean 294.8 vs. 293.4 mosmol/kg and 140.3 vs. 139.9 mmol/l. Plasma vasopressin was consistently below the limit of detection, and the plasma cortisol, aldosterone, and renin concentrations were similar in subjects with a high or low FRI. The very highest FRI values (≥ 5.0, N = 61 were always accompanied by albuminuria.Fluid retention consistent with moderate dehydration is common in healthy staff working in a Swedish hospital.

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

Science.gov (United States)

Strash, Carolyn

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

Retentiveness of implant-supported metal copings using different luting agents

Directory of Open Access Journals (Sweden)

Farahnaz Nejatidanesh

2012-01-01

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

Arctic water tracks retain phosphorus and transport ammonium

Science.gov (United States)

Harms, T.; Cook, C. L.; Wlostowski, A. N.; Godsey, S.; Gooseff, M. N.

2017-12-01

Hydrologic flowpaths propagate biogeochemical signals among adjacent ecosystems, but reactions may attenuate signals by retaining, removing, or transforming dissolved and suspended materials. The theory of nutrient spiraling describes these simultaneous reaction and transport processes, but its application has been limited to stream channels. We applied nutrient spiraling theory to water tracks, zero-order channels draining Arctic hillslopes that contain perennially saturated soils and flow at the surface either perennially or in response to precipitation. In the Arctic, experimental warming results in increased availability of nitrogen, the limiting nutrient for hillslope vegetation at the study site, which may be delivered to aquatic ecosystems by water tracks. Increased intensity of rain events, deeper snowpack, earlier snowmelt, and increasing thaw depth resulting from climate change might support increased transport of nutrients, but the reactive capacity of hillslope flowpaths, including sorption and uptake by plants and microbes, could counter transport to regulate solute flux. Characteristics of flowpaths might influence the opportunity for reaction, where slower flowpaths increase the contact time between solutes and soils or roots. We measured nitrogen and phosphorus uptake and transient storage of water tracks through the growing season and found that water tracks retain inorganic phosphorus, but transport ammonium. Nutrient uptake was unrelated to transient storage, suggesting high capacity for nutrient retention by shallow organic soils and vegetation. These observations indicate that increased availability of ammonium, the biogeochemical signal of warming tundra, is propagated by hillslope flowpaths, whereas water tracks attenuate delivery of phosphorus to aquatic ecosystems, where its availability typically limits production.

The ımpact of benefıts and servıces on manager engagement and manager retentıon ın tourısm ındustry: Enhanced by the effect of management level

OpenAIRE

ALDATMAZ, Ipek; AYKAÇ, Cansu; DICLE, Ülkü

2017-01-01

Manager engagement and retention are vital to the success and organizational performance of many service sector organisations. Maintaining manager retention is a major challenge that many hotel enterprises face today. It is critical that organizations give greater importance to manager engagement, motivation and retention and therefore establish an efficient benefits and services strategy for retaining these core managers for the persistence and achievement of the organization...

An investigation of the leaf retention capacity, efficiency and mechanism for atmospheric particulate matter of five greening tree species in Beijing, China.

Science.gov (United States)

Liu, Jinqiang; Cao, Zhiguo; Zou, Songyan; Liu, Huanhuan; Hai, Xiao; Wang, Shihua; Duan, Jie; Xi, Benye; Yan, Guangxuan; Zhang, Shaowei; Jia, Zhongkui

2018-03-01

Urban trees have the potential to reduce air pollution, but the retention capacity and efficiency of different tree species for atmospheric particulate matter (PM) accumulation and the underlying mechanism hasn't been well understood. To select tree species with high air purification abilities, the supplementing ultrasonic cleaning (UC) procedure was first introduced into the conventional leaf cleaning methods [single water cleaning (WC) or plus brush cleaning (BC)] for eluting the leaf-retained PM. Further updates to the methodology were applied to investigate the retention capacity, efficiency, and mechanism for PM of five typical greening tree species in Beijing, China. Meanwhile, the particle size distribution of PM on the leaves, the PM retention efficiencies of easily removable (ERP), difficult-to-remove (DRP) and totally removable (TRP) particles on the leaf (AE leaf ), and the individual tree scales were estimated. The experimental leaf samples were collected from trees with similar sizes 4 (SDR) and 14days (LDR) after rainfall. When the leaves were cleaned by WC+BC, there was, on average, 29%-46% of the PM remaining on the leaves of different species, which could be removed almost completely if UC was supplemented. From SDR to LDR, the mass of the leaf-retained PM increased greatly, and the particle size distribution changed markedly for all species except for Sophorajaponica. Pinus tabuliformis retains particles with the largest average diameter (34.2μm), followed by Ginkgo biloba (20.5μm), Sabina chinensis (16.4μm), Salix babylonica (16.0μm), and S. japonica (13.1μm). S. japonica and S. chinensis had the highest AE leaf to retain the TRP and ERP of both PM 1 and PM 1-2.5 , respectively. Conversely, S. babylonica and P. tabuliformis could retain both TRP and ERP of PM 2.5-5 and PM 5-10 , and PM >10 and TSP with the highest AE leaf , respectively. In conclusion, our results could be useful in selecting greening tree species with high air purification

Influence of thermal treatment on bentonite used as adsorbent for Cd, Pb, Zn retention from mono-solute and poly-solute aqueous solutions

Directory of Open Access Journals (Sweden)

Susana Yamila Martinez Stagnaro

2012-08-01

Full Text Available The retentions of Zn, Cd and Pb cations by one treated bentonite up to 750 °C were analyzed. The retentions were evaluated by using mono-and poly-solute aqueous solutions of such cations. The adsorptions were carried out in batch system at room temperature. The solid/liquid ratio was 2% wt.v-1. The solids were characterized by X-ray diffraction, thermal and chemical analyses. The Zn cation from mono- or polysolute-solutions was retained in higher amount than Cd and Pb cations in similar solution types by bentonite. The retentions were effective up to 450 °C calcined bentonite, after that, the retention capacity decreased in concordance with dehydroxylation of the structure of clay minerals.

77 FR 3745 - Establishment of a One-Year Retention Period for Patent-Related Papers That Have Been Scanned...

Science.gov (United States)

2012-01-25

... past practice of indefinitely retaining the papers, which has been rendered unnecessary and not cost...] Establishment of a One-Year Retention Period for Patent-Related Papers That Have Been Scanned Into the Image... period of one year for patent-related papers that have been scanned into the Image File Wrapper system...

Retention and mortality on antiretroviral therapy in sub-Saharan Africa: collaborative analyses of HIV treatment programmes.

Science.gov (United States)

Haas, Andreas D; Zaniewski, Elizabeth; Anderegg, Nanina; Ford, Nathan; Fox, Matthew P; Vinikoor, Michael; Dabis, François; Nash, Denis; Sinayobye, Jean d'Amour; Niyongabo, Thêodore; Tanon, Aristophane; Poda, Armel; Adedimeji, Adebola A; Edmonds, Andrew; Davies, Mary-Ann; Egger, Matthias

2018-02-01

By 2020, 90% of all people diagnosed with HIV should receive long-term combination antiretroviral therapy (ART). In sub-Saharan Africa, this target is threatened by loss to follow-up in ART programmes. The proportion of people retained on ART long-term cannot be easily determined, because individuals classified as lost to follow-up, may have self-transferred to another HIV treatment programme, or may have died. We describe retention on ART in sub-Saharan Africa, first based on observed data as recorded in the clinic databases, and second adjusted for undocumented deaths and self-transfers. We analysed data from HIV-infected adults and children initiating ART between 2009 and 2014 at a sub-Saharan African HIV treatment programme participating in the International epidemiology Databases to Evaluate AIDS (IeDEA). We used the Kaplan-Meier method to calculate the cumulative incidence of retention on ART and the Aalen-Johansen method to calculate the cumulative incidences of death, loss to follow-up, and stopping ART. We used inverse probability weighting to adjust clinic data for undocumented mortality and self-transfer, based on estimates from a recent systematic review and meta-analysis. We included 505,634 patients: 12,848 (2.5%) from Central Africa, 109,233 (21.6%) from East Africa, 347,343 (68.7%) from Southern Africa and 36,210 (7.2%) from West Africa. In crude analyses of observed clinic data, 52.1% of patients were retained on ART, 41.8% were lost to follow-up and 6.0% had died 5 years after ART initiation. After accounting for undocumented deaths and self-transfers, we estimated that 66.6% of patients were retained on ART, 18.8% had stopped ART and 14.7% had died at 5 years. Improving long-term retention on ART will be crucial to attaining the 90% on ART target. Naïve analyses of HIV cohort studies, which do not account for undocumented mortality and self-transfer of patients, may severely underestimate both mortality and retention on ART. © 2018 The

The Defense Acquisition Workforce Growth Initiative: Changing Workforce Characteristics and the Implications for Workforce Retention

Science.gov (United States)

2017-01-01

grow. The “DoD Procurement Budget” began to increase starting in the late 1990s (Gansler, Lucyshyn and Arendt , 2010, p. 2). And, according to one...related to higher rates of retention (Kammeyer-Mueller and Wanberg, 2003, p. 790). Beyer and Hannah (2002) use “qualitative” methods to investigate how...SEMATECH, which is a research “consortium” that uses loaned employees from other companies in the industry (Beyer and Hannah , 2002, p. 638). Beyer and

Practical solutions for staff recruitment & retention.

Science.gov (United States)

Vander Hoek, N

2001-01-01

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

A new type of intracellular retention signal identified in a pestivirus structural glycoprotein.

Science.gov (United States)

Burrack, Sandra; Aberle, Daniel; Bürck, Jochen; Ulrich, Anne S; Meyers, Gregor

2012-08-01

Sorting of membrane proteins into intracellular organelles is crucial for cell function. Viruses exploit intracellular transport and retention systems to concentrate envelope proteins at the site of virus budding. In pestiviruses, a group of important pathogens of pigs and ruminants closely related to human hepatitis C virus, the E(rns) protein translated from the viral RNA is secreted from the infected cells and found in the serum of infected animals. Secretion of the protein is regarded as crucial for its function as a viral virulence factor associated with its RNase activity. However, ∼95% of the E(rns) molecules are retained within the infected cell. Fusion of different E(rns) fragments to the C terminus of CD72 allowed identification of a retention signal within the C-terminal 65 aa of the viral protein. This C-terminal sequence represents its membrane anchor and folds into an amphipathic helix binding in-plane to the membrane surface. Residues L183, I190, and L208 are important for intracellular location of E(rns). Presentation of the retention signal on the cytoplasmic instead of the luminal face of the ER membrane in CD8α fusion proteins still led to retention. Thus, E(rns) contains in its C-terminal amphipathic helix an intracellular retention signal that is active on both faces of the membrane.

Does retained-seed priming drive the evolution of serotiny in drylands? An assessment using the cactus Mammillaria hernandezii.

Science.gov (United States)

Santini, Bianca A; Martorell, Carlos

2013-02-01

Serotinous plants retain their seeds for a long time. In deserts, retained seeds undergo hydration-dehydration cycles and thus may become primed. Priming enhances germination and seedling vigor. We test the hypothesis that serotiny evolves because it provides a site protected from predators in which seeds can become primed. Rainfall-cued dispersal of primed seeds may enhance this effect. We tested this hypothesis with Mammillaria hernandezii through protein-content analyses; field and laboratory germination experiments with primed, unprimed, and retained seeds; and fitness estimations from demographic models. Hydration-dehydration cycles induced priming, enhancing germination. Artificial priming and retention in the parent plant for 1 yr induced similar changes in seed protein patterns, suggesting that priming occurs naturally while seeds are retained. Under field conditions, germination of seeds retained for 1 yr more than doubled that of seeds of the same cohort that were not primed or that remained buried for 1 yr. The first seeds to germinate died rapidly. Serotinous plants whose seeds underwent priming had higher fitness than those whose seeds were in the soil seed bank or that did not experience priming. Priming in soil seed banks may be costly because of high predation, so seed protection during priming is sufficient to promote the evolution of serotiny. Bet hedging contributes to this process. Rapid germination of primed seeds that respond to brief rainfall events is disadvantageous because such rainfall is insufficient for seedling survival. Serotinous species counteract this cost by cueing dispersal with heavy precipitation.

Hydrogen retention in Li and Li-C-O films

Science.gov (United States)

Buzi, Luxherta; Nelson, Andrew O.; Yang, Yuxin; Kaita, Robert; Koel, Bruce E.

2017-10-01

The efficiency of Li in binding H isotopes has led to reduced recycling in magnetic fusion devices and improved plasma performance. Since elemental Li surfaces are challenging to maintain in fusion devices due to the presence of impurities, parameterizing and understanding the mechanisms for H retention in various Li compounds (Li-C-O), in addition to pure Li, is crucial for Li plasma-facing material applications. To determine H retention in Li and Li-C-O films, measurements were done under ultrahigh vacuum conditions using temperature programmed desorption (TPD). Thin Li films (20 monolayers) were deposited on a nickel single crystal substrate and irradiated with 500 eV H2+ions at surface temperatures from 90K to 520K. Initial measurements on Li and Li-O films showed that the retention was comparable and dropped exponentially with surface temperature, from 95% at 90 K to 35% at 520 K. Auger electron spectroscopy and TPD showed that H was retained as lithium hydride (LiH) in pure Li and as lithium hydroxide (LiOH) in Li2O, which decomposed to H2O and Li2O at temperatures higher than 470K. H retention in Li-C and Li-C-O films will be determined over a similar temperature range, and the sputtering rate of these layers with H ions will also be reported. This material is based upon work supported by the U.S. Department of Energy, Office of Science/Fusion Energy Sciences under Award Number DE-SC0012890.

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

Directory of Open Access Journals (Sweden)

Donald J Ferguson

2016-01-01

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

Customer retention management for the hotel industry in Gauteng / Daniël Johannes Petzer

OpenAIRE

Petzer, Daniël Johannes

2005-01-01

The effects of globalisation, local economic conditions, and developments in the service-, tourism-, and hotel industries, as well as increasing competitiveness, have led to major changes in the operating environment of South African hotels, in Gauteng particularly. These changes necessitate marketing responses from the hotels so that they can gain, but also (more profitably) retain customers. The present study develops a customer retention framework for Gauteng hotels. The ...

Influence of usual zinc intake and zinc in a meal on 65Zn retention and turnover in the rat

International Nuclear Information System (INIS)

Hunt, J.R.; Johnson, P.E.; Swan, P.B.

1987-01-01

The influences of zinc in a meal and usual zinc intake on zinc retention and turnover were investigated in 7-wk-old male rats fed diets containing 12-151 mg Zn/kg for 3 wk before and after consuming a 65 Zn-labeled meal containing ZnCl 2 . Retention corrected to zero time and turnover rate were determined by whole-body counting. Percent zinc retention was inversely proportional to the natural logarithm of the meal zinc, between 0.09 and 26 mumol. In comparison to lower doses, higher doses resulted in lower percent retention but greater amounts of zinc retained. Although the latter relationship was slightly curvilinear, there was no indication of a limited capacity for zinc retention with high doses. However, doses above 4 mumol resulted in higher turnover rates in rats accustomed to lower zinc intakes. Percent retention and the reciprocal of the turnover rate were proportional to the reciprocal of the dietary zinc concentration. The greatest differences in retention and turnover occurred between 12 and 26 mg Zn/kg diet. The zinc dose in a meal and the usual dietary zinc separately influenced percent zinc retention. These factors also interacted, such that greater dose effects were observed at lower zinc intakes and greater dietary zinc effects were observed at lower doses

Client retention and health among sex workers in Nairobi, Kenya.

Science.gov (United States)

Izugbara, Chimaraoke O

2012-12-01

It is still a small body of research that directly addresses female sex workers' relationships with their regular commercial male partners. I used ethnographic data from Nairobi, Kenya to interrogate motivations and strategies for recruiting and retaining regular male clients among female sex workers (FSWs). Regular commercial male partners, popularly called customer care, wera or wesh by Nairobi's FSWs, played diverse roles in their lives. Client retention enabled sex workers to manage the risk of reduced marriage prospects, guaranteed them steady work, livelihoods, and incomes, and prevented their victimization and harassment. To retain clients, sex workers obliged them a great deal, pretended they had quit prostitution, and sometimes resorted to magical practices. However, these strategies were also accompanied by risks that reinforced the vulnerability of sex workers. Lack of critical attention to sex workers' practices for managing perceived risks in their particular type of work may hamper current programmatic efforts to make their job safer.

Managing the academic talent void: Investigating factors in academic turnover and retention in South Africa

Directory of Open Access Journals (Sweden)

Marguerite Theron

2014-04-01

Research purpose: This study aimed to investigate the factors that influence turnover and retention of academic and to validate the developed talent retention diagnostic tool for use in South African higher education institutions. Motivation for the study: Limited research currently exists on the retention factors of academic staff in the South African context. Research approach, design and method: Using an investigative quantitative research approach, the tool was administered to a convenience sample of academics (n = 153 in 13 higher education institutions. Main findings: The results showed an array of distinguishing turnover and retention factors and proved the tool to be a valid and reliable measure. Over half the respondents indicated slight to strong dissatisfaction with compensation and performance management practices. Significantly, 34% indicated that they considered exiting their academic institution, citing unhappiness about compensation, as the most likely reason, whilst 74.5% have previously looked for another job. Practical/managerial implications: The research highlights key areas (i.e. compensation, emotional recognition, a bonus structure that reflects employee contribution, performance management systems, mentorship and career development opportunities that higher education should attend to if they want to retain their key and talented academic staff. Contribution/value-add: The results contribute to new knowledge on the factors that contribute to turnover and retention of academic staff and present a valid and reliable measure to assess these retention factors.

Developing a framework for relationship intention, satisfaction, loyalty and retention of SMEs in the business-to-business financing environment / Margaretha Henriëtha Mentz

OpenAIRE

Mentz, Margaretha Henriëtha

2014-01-01

In the business-to-business (B2B) financing industry, financiers offering financing to SMEs are finding it increasingly difficult to attract new customers and to retain existing customers. One way of attracting and retaining customers is by creating superior customer satisfaction, as it is believed that customer satisfaction leads to loyalty which ultimately results in customer retention. Customer satisfaction could also be an important indicator as to whether customers would want to build lo...

Characterizing retention in HAART as a recurrent event process: insights into 'cascade churn'.

Science.gov (United States)

Nosyk, Bohdan; Lourenço, Lillian; Min, Jeong Eun; Shopin, Dimitry; Lima, Viviane D; Montaner, Julio S G

2015-08-24

The benefits of HAART rely on continuous lifelong treatment retention. We used linked population-level health administrative data to characterize durations of HAART retention and nonretention. This is a retrospective cohort study. We considered individuals initiating HAART in British Columbia (1996-2012). An HAART episode was considered discontinued if individuals had a gap of at least 30 days between days in which medication was prescribed. We considered durations of HAART retention and nonretention separately, and used Cox proportional hazards frailty models to identify demographic and treatment-related factors associated with durations of HAART retention and nonretention. Six thousand one hundred fifty-two individuals were included in the analysis; 81.2% were male, 40.6% were people who inject drugs, and 42.8% initiated treatment with CD4 cell count less than 200 cells/μl. Overall, 29% were continuously retained on HAART through the end of follow-up. HAART episodes were a median 6.8 months (25th, 75th percentile: 2.3, 19.5), whereas off-HAART episodes lasted a median 1.9 months (1.2, 4.5). In Cox proportional hazards frailty models, durations of HAART retention improved over time. Successive treatment episodes tended to decrease in duration among those with multiple attempts, whereas off-HAART episodes remained relatively stable. Younger age, earlier stages of disease progression, and injection drug use were all associated with shorter durations of HAART retention and longer off-HAART durations. Metrics to monitor HAART retention, dropout, and reentry should be prioritized for HIV surveillance. Clinical strategies and public health policies are urgently needed to improve HAART retention, particularly among those at earlier stages of disease progression, the young, and people who inject drugs.

Analysis of multiple instructional techniques on the understanding and retention of select mechanical topics

Science.gov (United States)

Fetsco, Sara Elizabeth

There are several topics that introductory physics students typically have difficulty understanding. The purpose of this thesis is to investigate if multiple instructional techniques will help students to better understand and retain the material. The three units analyzed in this study are graphing motion, projectile motion, and conservation of momentum. For each unit students were taught using new or altered instructional methods including online laboratory simulations, inquiry labs, and interactive demonstrations. Additionally, traditional instructional methods such as lecture and problem sets were retained. Effectiveness was measured through pre- and post-tests and student opinion surveys. Results suggest that incorporating multiple instructional techniques into teaching will improve student understanding and retention. Students stated that they learned well from all of the instructional methods used except the online simulations.

Ferromagnetic Bare Metal Stent for Endothelial Cell Capture and Retention.

Science.gov (United States)

Uthamaraj, Susheil; Tefft, Brandon J; Hlinomaz, Ota; Sandhu, Gurpreet S; Dragomir-Daescu, Dan

2015-09-18

Rapid endothelialization of cardiovascular stents is needed to reduce stent thrombosis and to avoid anti-platelet therapy which can reduce bleeding risk. The feasibility of using magnetic forces to capture and retain endothelial outgrowth cells (EOC) labeled with super paramagnetic iron oxide nanoparticles (SPION) has been shown previously. But this technique requires the development of a mechanically functional stent from a magnetic and biocompatible material followed by in-vitro and in-vivo testing to prove rapid endothelialization. We developed a weakly ferromagnetic stent from 2205 duplex stainless steel using computer aided design (CAD) and its design was further refined using finite element analysis (FEA). The final design of the stent exhibited a principal strain below the fracture limit of the material during mechanical crimping and expansion. One hundred stents were manufactured and a subset of them was used for mechanical testing, retained magnetic field measurements, in-vitro cell capture studies, and in-vivo implantation studies. Ten stents were tested for deployment to verify if they sustained crimping and expansion cycle without failure. Another 10 stents were magnetized using a strong neodymium magnet and their retained magnetic field was measured. The stents showed that the retained magnetism was sufficient to capture SPION-labeled EOC in our in-vitro studies. SPION-labeled EOC capture and retention was verified in large animal models by implanting 1 magnetized stent and 1 non-magnetized control stent in each of 4 pigs. The stented arteries were explanted after 7 days and analyzed histologically. The weakly magnetic stents developed in this study were capable of attracting and retaining SPION-labeled endothelial cells which can promote rapid healing.

Grass Plants Bind, Retain, Uptake, and Transport Infectious Prions

Directory of Open Access Journals (Sweden)

Sandra Pritzkow

2015-05-01

Full Text Available Prions are the protein-based infectious agents responsible for prion diseases. Environmental prion contamination has been implicated in disease transmission. Here, we analyzed the binding and retention of infectious prion protein (PrPSc to plants. Small quantities of PrPSc contained in diluted brain homogenate or in excretory materials (urine and feces can bind to wheat grass roots and leaves. Wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. The prion-plant interaction occurs with prions from diverse origins, including chronic wasting disease. Furthermore, leaves contaminated by spraying with a prion-containing preparation retained PrPSc for several weeks in the living plant. Finally, plants can uptake prions from contaminated soil and transport them to aerial parts of the plant (stem and leaves. These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease.

Factors related to employers' intent to hire, retain and accommodate cancer survivors: the Singapore perspective.

Science.gov (United States)

Mak, Angela Ka Ying; Ho, Shirley S; Kim, Hyo Jung

2014-12-01

Despite the growing importance of cancer and return-to-work issues in occupational rehabilitation literature in the last decade, academic discussion is largely limited to survivors' perspectives and some exploratory studies from the employer side. This paper applies two classic theoretical models-Theory of Planned Behavior and Social Cognitive Theory-and key measures from previous studies to identify explicit relationships that explain employer factors to hire and retain cancer survivors. Data were collected from online surveys with senior management executives and senior human resource specialists from various organizations in Singapore, with a total of 145 responses. The 72-item survey instrument included a series of independent variables: (1) Attitudes toward cancer and cancer survivors; (2) Employers' efficacy; (3) Perceived moral obligation; (4) Employers' experience; (5) Outcome expectations; (6) Employment situation; (7) Social norms; and (8) Incentives, and dependent variables: (a) Employers' intention to hire cancer survivors; and (b) Employers' intention to retain cancer survivors. Regression analyses showed that the top three factors related to employers' intention to retain cancer survivors are perceived moral obligations (β = .39, p employment situation (β = .17, p Employers' efficacy was associated with intention to hire (β = .22, p employer and an employee when it comes to retaining cancer survivors and government incentives for hiring cancer survivors in the workforce. The present study provided an avenue to implement the proposed model-a potential study framework for the management of cancer survivors at work. Findings revealed that different messages should be tailored to employers toward hiring and retention issues and provided useful guidelines for employer education materials.

The characterization of radiocaesium transport and retention in Nordic lakes

International Nuclear Information System (INIS)

Bjoernstad, H.E.; Brittain, J.E.; Saxen, R.; Sundblad, B.

1994-01-01

Fractionation studies of radiocaesium have been carried out in three Nordic lakes, Oevre Heimdalsvatn in Norway, Hillesjoen in Sweden and Saarisjaervi in Finland. These lakes differ markedly in several aspects and provide insight into the factors determining radionuclide transport in a range of lake ecosystems. Transport of 137 Cs in plant material (Coarse Particulate Organic Matter, CPOM) was about 17 times greater to Oevre Heimdalsvatn than Saarisjaervi, although over 99% of the inflow CPOM was retained in both lakes. Inflows to Hillesjoen were an order of magnitude lower than to Saarisjaervi and the net retention was only 71%, on account of the outflow of autochthonous production, largely water lily fragments. With regard to the water phase, the lakes differed in the activity of 137 Cs in the various molecular weight fractions. This was a function of catchment processes, resuspension and biological activity in the lakes. In Oevre Heimdalsvatn and Saarisjaervi 45% of the 137 Cs in the water phase was retained in the lake, while in Hillesjoen ten times more 137 Cs in the water phase was retained in the lake, while in Hillesjoen ten times more 137 Cs flowed out than flowed in, due to resuspension of 137 Cs-rich sediments. (orig.)

Recent Advances on Hydrogenic Retention in ITER's Plasma-Facing Materials: BE, C, W

International Nuclear Information System (INIS)

Skinner, C.H.; Haasz, A.A.; Alimov, V.Kh.; Bekris, N.; Causey, R.A.; Clark, R.E.H.; Coad, J.P.; Davis, J.W.; Doerner, R.P.; Mayer, M.; Pisarev, A.; Roth, J.; Tanabe, T.

2008-01-01

Management of tritium inventory remains one of the grand challenges in the development of fusion energy and the choice of plasma-facing materials is a key factor for in-vessel tritium retention. The Atomic and Molecular Data Unit of the International Atomic Energy Agency organized a Coordinated Research Project (CRP) on the overall topic of tritium inventory in fusion reactors during the period 2001-2006. This dealt with hydrogenic retention in ITER's plasma-facing materials, Be, C, W, and in compounds (mixed materials) of these elements as well as tritium removal techniques. The results of the CRP are summarized in this article together with recommendations for ITER. Basic parameters of diffusivity, solubility and trapping in Be, C and W are reviewed. For Be, the development of open porosity can account for transient hydrogenic pumping but long term retention will be dominated by codeposition. Codeposition is also the dominant retention mechanism for carbon and remains a serious concern for both Be and C containing layers. Hydrogenic trapping in unirradiated tungsten is low but will increase with ion and neutron damage. Mixed materials will be formed in a tokamak and these can also retain significant amounts of hydrogen isotopes. Oxidative and photon-based techniques for detritiation of plasma-facing components are described

Recent Advances on Hydrogenic Retention in ITER's Plasma-Facing Materials: BE, C, W.

Energy Technology Data Exchange (ETDEWEB)

Skinner, C H; Alimov, Kh; Bekris, N; Causey, R A; Clark, R.E.H.; Coad, J P; Davis, J W; Doerner, R P; Mayer, M; Pisarev, A; Roth, J

2008-03-29

Management of tritium inventory remains one of the grand challenges in the development of fusion energy and the choice of plasma-facing materials is a key factor for in-vessel tritium retention. The Atomic and Molecular Data Unit of the International Atomic Energy Agency organized a Coordinated Research Project (CRP) on the overall topic of tritium inventory in fusion reactors during the period 2001-2006. This dealt with hydrogenic retention in ITER's plasma-facing materials, Be, C, W, and in compounds (mixed materials) of these elements as well as tritium removal techniques. The results of the CRP are summarized in this article together with recommendations for ITER. Basic parameters of diffusivity, solubility and trapping in Be, C and W are reviewed. For Be, the development of open porosity can account for transient hydrogenic pumping but long term retention will be dominated by codeposition. Codeposition is also the dominant retention mechanism for carbon and remains a serious concern for both Be and C containing layers. Hydrogenic trapping in unirradiated tungsten is low but will increase with ion and neutron damage. Mixed materials will be formed in a tokamak and these can also retain significant amounts of hydrogen isotopes. Oxidative and photon-based techniques for detritiation of plasma-facing components are described.

Recruitment and retention of young women into nutrition research studies: practical considerations.

Science.gov (United States)

Leonard, Alecia; Hutchesson, Melinda; Patterson, Amanda; Chalmers, Kerry; Collins, Clare

2014-01-16

Successful recruitment and retention of participants into research studies is critical for optimising internal and external validity. Research into diet and lifestyle of young women is important due to the physiological transitions experienced at this life stage. This paper aims to evaluate data related to recruitment and retention across three research studies with young women, and present practical advice related to recruiting and retaining young women in order to optimise study quality within nutrition research. Recruitment and retention strategies used in three nutrition studies that targeted young women (18 to 35 years) were critiqued. A randomised controlled trial (RCT), a crossover validation study and a cross-sectional survey were conducted at the University of Newcastle, Australia between 2010 and 2013Successful recruitment was defined as maximum recruitment relative to time. Retention was assessed as maximum participants remaining enrolled at study completion. Recruitment approaches included notice boards, web and social network sites (Facebook and Twitter), with social media most successful in recruitment. The online survey had the highest recruitment in the shortest time-frame (751 participants in one month). Email, phone and text message were used in study one (RCT) and study two (crossover validation) and assisted in low attrition rates, with 93% and 75.7% completing the RCT and crossover validation study respectively. Of those who did not complete the RCT, reported reasons were: being too busy; and having an unrelated illness. Recruiting young women into nutrition research is challenging. Use of social media enhances recruitment, while Email, phone and text message contact improves retention within interventions. Further research comparing strategies to optimise recruitment and retention in young women, including flexible testing times, reminders and incentives is warranted.

Transport and retention of biochar nanoparticles in a paddy soil under environmentally-relevant solution chemistry conditions.

Science.gov (United States)

Chen, Ming; Wang, Dengjun; Yang, Fan; Xu, Xiaoyun; Xu, Nan; Cao, Xinde

2017-11-01

Land application of biochar has been increasingly recommended as a powerful strategy for carbon sequestration and soil remediation. However, the biochar particles, especially those in the nanoscale range, may migrate or carry the inherent contaminants along the soil profile, posing a potential risk to the groundwater. This study investigated the transport and retention of wood chip-derived biochar nanoparticles (NPs) in water-saturated columns packed with a paddy soil. The environmentally-relevant soil solution chemistry including ionic strength (0.10-50 mM), electrolyte type (NaCl and CaCl 2 ), and natural organic matter (0-10 mg L -1 humic acid) were tested to elucidate their effects on the biochar NPs transport. Higher mobility of biochar NPs was observed in the soil at lower ionic strengths, with CaCl 2 electrolyte being more effective than NaCl in decreasing biochar NPs transport. The retained biochar NPs in NaCl was re-entrained (∼57.7%) upon lowering transient pore-water ionic strength, indicating that biochar NPs were reversibly retained in the secondary minimum. In contrast, negligible re-entrainment of biochar NPs occurred in CaCl 2 due to the primary minimum and/or particle aggregation. Humic acid increased the mobility of biochar NPs, likely due to enhanced electrosteric repulsive interactions. The transport behaviors of biochar NPs can be well interpreted by a two-site kinetic retention model that assumes reversible retention for one site, and irreversible retention for the other site. Our findings indicated that the transport of wood chip biochar NPs is significant in the paddy soil, highlighting the importance of understanding the mobility of biochar NPs in natural soils for accurately assessing their environmental impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Retention and chemical speciation of uranium in an oxidized wetland sediment from the Savannah River Site

Energy Technology Data Exchange (ETDEWEB)

Li, Dien; Seaman, John C.; Chang, Hyun-Shik; Jaffe, Peter R.; Koster van Groos, Paul; Jiang, De-Tong; Chen, Ning; Lin, Jinru; Arthur, Zachary; Pan, Yuanming; Scheckel, Kirk G.; Newville, Matthew; Lanzirotti, Antonio; Kaplan, Daniel I.

2014-05-01

Uranium speciation and retention mechanism onto Savannah River Site (SRS) wetland sediments was studied using batch (ad)sorption experiments, sequential extraction desorption tests and U L{sub 3}-edge X-ray absorption near-edge structure (XANES) spectroscopy of contaminated wetland sediments. U was highly retained by the SRS wetland sediments. In contrast to other similar but much lower natural organic matter (NOM) sediments, significant sorption of U onto the SRS sediments was observed at pH <4 and pH >8. Sequential extraction tests indicated that the U(VI) species were primarily associated with the acid soluble fraction (weak acetic acid extractable) and NOM fraction (Na-pyrophosphate extractable). Uranium L3- edge XANES spectra of the U-retained sediments were nearly identical to that of uranyl acetate. The primary oxidation state of U in these sediments was as U(VI), and there was little evidence that the high sorptive capacity of the sediments could be ascribed to abiotic or biotic reduction to the less soluble U(IV) species. The molecular mechanism responsible for the high U retention in the SRS wetland sediments is likely related to the chemical bonding of U to organic carbon.

Rate of radiocarbon retention onto calcite by isotope exchange

Energy Technology Data Exchange (ETDEWEB)

Lempinen, Janne; Lehto, Jukka [Helsinki Univ. (Finland). Lab. of Radiochemistry

2016-11-01

Radiocarbon ({sup 14}C) is a top priority class radionuclide associated with the long-term safety of spent nuclear fuel disposal. Dissolved inorganic radiocarbon can be retained in bedrock via isotope exchange with calcite (CaCO{sub 3}) at solubility equilibrium with groundwater. In the present study, the rate of the isotope exchange process was investigated on synthetic calcite using batch experiments. Experiments were performed in solutions with a calcium concentration of 0.0002-0.1 M, including two synthetic reference groundwaters. The radiocarbon activity in the solutions decreased exponentially as a function of time, thus following first-order kinetics. The rate of isotope exchange was quantified from an exponential fit to the activity data over time. The rate of radiocarbon retention increased as a function of the calcium activity. The isotope exchange half-life was only 4.3 days at calcium ion activities over 0.01. This half-life is very much shorter than the half-life of {sup 14}C or the time scale of groundwater movements; consequently calcite can effectively retain radiocarbon from brackish and saline groundwaters.

Rate of radiocarbon retention onto calcite by isotope exchange

International Nuclear Information System (INIS)

Lempinen, Janne; Lehto, Jukka

2016-01-01

Radiocarbon ( 14 C) is a top priority class radionuclide associated with the long-term safety of spent nuclear fuel disposal. Dissolved inorganic radiocarbon can be retained in bedrock via isotope exchange with calcite (CaCO 3 ) at solubility equilibrium with groundwater. In the present study, the rate of the isotope exchange process was investigated on synthetic calcite using batch experiments. Experiments were performed in solutions with a calcium concentration of 0.0002-0.1 M, including two synthetic reference groundwaters. The radiocarbon activity in the solutions decreased exponentially as a function of time, thus following first-order kinetics. The rate of isotope exchange was quantified from an exponential fit to the activity data over time. The rate of radiocarbon retention increased as a function of the calcium activity. The isotope exchange half-life was only 4.3 days at calcium ion activities over 0.01. This half-life is very much shorter than the half-life of 14 C or the time scale of groundwater movements; consequently calcite can effectively retain radiocarbon from brackish and saline groundwaters.

Dynamic fuel retention in tokamak wall materials: An in situ laboratory study of deuterium release from polycrystalline tungsten at room temperature

Energy Technology Data Exchange (ETDEWEB)

Bisson, R., E-mail: regis.bisson@univ-amu.fr [Aix Marseille Université, CNRS, PIIM UMR 7345, 13397 Marseille (France); Markelj, S. [Aix Marseille Université, CNRS, PIIM UMR 7345, 13397 Marseille (France); Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Mourey, O.; Ghiorghiu, F. [Aix Marseille Université, CNRS, PIIM UMR 7345, 13397 Marseille (France); Achkasov, K. [Aix Marseille Université, CNRS, PIIM UMR 7345, 13397 Marseille (France); CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Layet, J.-M.; Roubin, P.; Cartry, G. [Aix Marseille Université, CNRS, PIIM UMR 7345, 13397 Marseille (France); Grisolia, C. [CEA, IRFM, F-13108 Saint-Paul-lez-Durance (France); Angot, T. [Aix Marseille Université, CNRS, PIIM UMR 7345, 13397 Marseille (France)

2015-12-15

Retention of deuterium ion implanted in polycrystalline tungsten samples is studied in situ in an ultra-high vacuum apparatus equipped with a low-flux ion source and a high sensitivity thermo-desorption setup. Retention as a function of ion fluence was measured in the 10{sup 17}–10{sup 21} D{sup +}·m{sup −2} range. By combining this new fluence range with the literature in situ experimental data, we evidence the existence of a retention ∝ fluence{sup 0.645±0.025} relationship which describes deuterium retention behavior on polycrystalline tungsten on 8 orders of magnitude of fluence. Evolution of deuterium retention as a function of the sample storage time in vacuum at room temperature was followed. A loss of 50% of the retained deuterium is observed when the storage time is increased from 2 h to 135 h. The role of the surface and of natural bulk defects on the deuterium retention/release in polycrystalline tungsten is discussed in light of the behavior of the single desorption peak obtained with Temperature Programmed Desorption.

Dynamical analysis of mCAT2 gene models with CTN-RNA nuclear retention

International Nuclear Information System (INIS)

Wang, Qianliang; Zhou, Tianshou

2015-01-01

As an experimentally well-studied nuclear-retained RNA, CTN-RNA plays a significant role in many aspects of mouse cationic amino acid transporter 2 (mCAT2) gene expression, but relevant dynamical mechanisms have not been completely clarified. Here we first show that CTN-RNA nuclear retention can not only reduce pre-mCAT2 RNA noise but also mediate its coding partner noise. Then, by collecting experimental observations, we conjecture a heterodimer formed by two proteins, p54 nrb and PSP1, named p54 nrb -PSP1, by which CTN-RNA can positively regulate the expression of nuclear mCAT2 RNA. Therefore, we construct a sequestration model at the molecular level. By analyzing the dynamics of this model system, we demonstrate why most nuclear-retained CTN-RNAs stabilize at the periphery of paraspeckles, how CTN-RNA regulates its protein-coding partner, and how the mCAT2 gene can maintain a stable expression. In particular, we obtain results that can easily explain the experimental phenomena observed in two cases, namely, when cells are stressed and unstressed. Our entire analysis not only reveals that CTN-RNA nuclear retention may play an essential role in indirectly preventing diseases but also lays the foundation for further study of other members of the nuclear-regulatory RNA family with more complicated molecular mechanisms. (paper)

Building customer relationships as retention strategy in the South African domestic passenger airline industry

Directory of Open Access Journals (Sweden)

Pierre Mostert

2010-12-01

Full Text Available Organisations are increasingly focusing on building long-term relationships with customers, thereby increasing their probability for success by offering customers higher levels of satisfaction, increasing customer loyalty, and ultimately retaining customers. Airlines in particular can benefit from retaining customers as the airline industry is characterised by fierce competition and many airlines are finding it difficult to survive against the backdrop of enormous challenges in the past decade, including the significant decline in demand for air travel together with rising costs and the worldwide economic downturn. This study investigates the effect which a strategy by airlines of building relationships with customers has on customer satisfaction, loyalty, and ultimately customer retention. The effect of service failures on customers' relationships with airlines are also considered as a negative experience could results in customers defecting to competitors. A questionnaire, comprising six sections, was specifically compiled to determine customer retention in the South African domestic passenger airline industry. Data were collected by trained fieldworkers from OR Tambo International Airport by means of a non-probability convenience sampling method from 324 passengers flying with the various domestic airlines. Findings indicate that most respondents were satisfied with the airlines' overall service; respondents who formed relationships with domestic airlines were more loyal toward the airlines; and the relationships of respondents who were satisfied with airlines' service recovery efforts were either strengthened or unchanged. The findings from this study support findings from international studies by providing a unique South African perspective on the effect of a strategy of building relationships with customers on their satisfaction, loyalty and ultimately retention. It can therefore be recommended that the organisations competing in the South

Study of Trehalose Addition on Aroma Retention in Dehydrated Strawberry Puree

Directory of Open Access Journals (Sweden)

Draženka Komes

2003-01-01

Full Text Available In order to improve the quality of dehydrated fruit products, the influence of the addition of two sugars (sucrose and trehalose on the retention of aroma components during dehydration of strawberry puree was investigated. Manual headspace solid-phase microextraction (SPME, containing polydimethylsiloxane coated fibre (100 μm coupled with gas chromatography (GC-FID and GC-MS was used for the analysis of the aroma of strawberry puree dehydrated by using freeze drying and foam-mat drying. The analytes identified included esters, carbonyl compounds, terpenoids, several alcohols and acids. The results obtained in this study give further insight into the mechanisms concerning the application of trehalose as flavouring additive, due to its ability to retain and preserve the fruit volatiles responsible for the characteristic flavour of fresh fruits during dehydration processes. The best retention of aroma components in dehydrated strawberry puree was obtained by trehalose addition when combined with freeze drying.

Going the Distance: Overcoming Challenges in Recruitment and Retention of Black and White Women to a Multi-Site, Longitudinal Study of Predictors of Coronary Heart Disease

OpenAIRE

2009-01-01

High recruitment and retention rates are hallmarks of scientifically rigorous longitudinal research. However, recruitment and retention are challenging, especially with elders and minorities. In this article, we discuss strategies that have enabled us to retain over 80% of both Black and White women in a 5-year observational study. To overcome such challenges as staff turnover and introduction of computerized record systems, we developed a time-saving handout, streamlined procedures for docum...

Retention system for implant-supported dentures used by brazilian dentists who work in implant dentistry

Directory of Open Access Journals (Sweden)

Saturnino Aparecido Ramalho

2010-04-01

Full Text Available Objective: To provide the dentists with support in the choice of the cement or screw type of retention for implant-supported dentures, according to the patient’s problem. Methods: An opinion questionnaire was applied to a sample of 468 participants, all dentists working in the field of Implant Dentistry, of whom 272 (58.1% participated in the 4th International Congress of Osseointegration of APCD, held in São Paulo (SP from 6 to 9 May 2004, 119 (25.4% participated in the 2nd International Congress of Implant Dentistry of Minas Gerais, between 10 and 12 June 2004 and 77 (16.5% were professors and specialization and master students from São Leopoldo Mandic. Results: The results showed that 254 participants opted for the screw-retained system while 214 opted for the cement-retained system. Conclusion: There was a preference for the use of the screw-retained system, and that both cemented and screw-retained systems have advantages and disadvantages, so that the dentist is left to decide and evaluate them in order to indicate and use them with confidence in different clinical cases.

Characterizing retention in HAART as a recurrent event process: insights into ‘cascade churn’

Science.gov (United States)

Nosyk, Bohdan; Lourenço, Lillian; Min, Jeong Eun; Shopin, Dimitry; Lima, Viviane D.; Montaner, Julio S.G.

2015-01-01

Objective The benefits of HAART rely on continuous lifelong treatment retention. We used linked population-level health administrative data to characterize durations of HAART retention and nonretention. Design This is a retrospective cohort study. Methods We considered individuals initiating HAART in British Columbia (1996–2012). An HAART episode was considered discontinued if individuals had a gap of at least 30 days between days in which medication was prescribed. We considered durations of HAART retention and nonretention separately, and used Cox proportional hazards frailty models to identify demographic and treatment-related factors associated with durations of HAART retention and nonretention. Results Six thousand one hundred fifty-two individuals were included in the analysis; 81.2% were male, 40.6% were people who inject drugs, and 42.8% initiated treatment with CD4 cell count less than 200 cells/μl. Overall, 29% were continuously retained on HAART through the end of follow-up. HAART episodes were a median 6.8 months (25th, 75th percentile: 2.3, 19.5), whereas off-HAART episodes lasted a median 1.9 months (1.2, 4.5). In Cox proportional hazards frailty models, durations of HAART retention improved over time. Successive treatment episodes tended to decrease in duration among those with multiple attempts, whereas off-HAART episodes remained relatively stable. Younger age, earlier stages of disease progression, and injection drug use were all associated with shorter durations of HAART retention and longer off-HAART durations. Conclusion Metrics to monitor HAART retention, dropout, and reentry should be prioritized for HIV surveillance. Clinical strategies and public health policies are urgently needed to improve HAART retention, particularly among those at earlier stages of disease progression, the young, and people who inject drugs. PMID:26372279

Retained surgical sponge

International Nuclear Information System (INIS)

Koyama, Masashi; Kurono, Kenji; Iida, Akihiko; Suzuki, Hirochika; Hara, Masaki; Mizutani, Hirokazu; Ohba, Satoru; Mizutani, Masaru; Nakajima, Yoichiro.

1993-01-01

The CT, US, and MRI findings of confirmed retained surgical sponges were reviewed. The CT examinations in eight lesions demonstrated round or oval masses with heterogeneous internal structures. The US examinations in 5 lesions demonstrated low echogenic masses with high echogenic internal structures, which suggested retained surgical sponges. MR imagings in three lesions showed slightly high intensity comparable to that of muscles on T1-weighted images and high signal intensity on T2-weighted images, suggesting fluid collections of high protein concentration. (author)

A Nursing Workforce Diversity Project: Strategies for Recruitment, Retention, Graduation, and NCLEX-RN Success.

Science.gov (United States)

Murray, Ted A; Pole, David C; Ciarlo, Erica M; Holmes, Shearon

2016-01-01

The purpose of this article is to describe a collaborative project designed to recruit and retain students from underrepresented minorities and disadvantaged backgrounds into nursing education. Ethnic minorities remain underrepresented in the nursing workforce in comparison to the general population. The numbers of minorities enrolled in nursing education programs are insufficient to meet the health care workforce diversity needs of the future. High school students were provided with a preprofessional education program to prepare them for admission into a nursing program. Retention strategies were implemented for newly admitted and enrolled nursing education students. Twenty-one high school students enrolled in a nursing education program. The students enrolled in the nursing education program graduated and passed the licensure examination. Early recruitment and multiprong retention programs can be successful in diversifying the registered nurse workforce.

Quantitative assessment of radionuclide retention in the near-surface system at Forsmark. Development of a reactive transport model using Forsmark 1.2 data

International Nuclear Information System (INIS)

Grandia, Fidel; Sena, Clara; Arcos, David; Molinero, Jorge; Duro, Lara; Bruno, Jordi

2007-12-01

been selected for quantitative modelling based on the availability of data and parameters. Two distinct geological and hydrogeological domains have been considered: (1) the till system and (2) the clay system. The first case simulates the intrusion of a radionuclide-bearing fluid from granite bedrock into a relatively dynamic till aquifer. In the second case, the radionuclide bearing fluid interacts with a low permeability, reducing clay layer that is present at the bottom of a discharge zone (such as a lake or the Baltic Sea, for instance), overlying the till deposit. Groundwater flow and transport modelling results highlight the different behaviour of the two simulated systems. The till system constitutes a dynamic aquifer, which reaches the transport steady-state in less than 8 years. On the other hand, the clay system constitutes a relatively low permeability aquitard in which the transport steady state needs hundreds of years to be reached. Reactive transport results indicate that caesium is very strongly retained in the FES of illite in both till and clay systems. Most of the caesium mass entering the system from the deep source is effectively retained in the very close vicinity of the source, independently of the hydrogeological conditions. In the case of uranium, the most effective processes for retention are very different depending on the two considered hydrogeological systems. In the till aquifer, the dissolved uranium is mainly adsorbed onto the charged surfaces of ferrihydrite. It is seen that this dynamic aquifer system still exhibits a uranium retention efficiency of about 50% even after about 100 years of simulation time. On the other hand, the simulated clay system is much more efficient than the till aquifer for uranium retention due to the precipitation of amorphous uranium (IV) oxides. Uranium retention efficiencies higher than 95% are computed for the clay system, even after more than 400 years. As in the case of caesium, most of the uranium mass

Overdenture retained by teeth using a definitive denture base technique: a case report.

Science.gov (United States)

Nascimento, D F F; dos Santos, J F F; Marchini, L

2010-09-01

This paper presents a technique involving the use of a definitive denture base to make overdentures. Cores with ball attachments were cemented over remaining lower teeth. Impressions of the edentulous maxilla and mandible were taken to obtain a definitive acrylic resin base. The definitive base of the mandible was perforated at the location of ball attachments and its female components were fixed to the base using acrylic resin directly in the patient's mouth. Wax rims were then made, jaw relationships recorded, teeth mounted and tried in, and the dentures were cured. This technique allowed for easy fixing of female components and better retention during the recording of jaw relationships, and can also be used in the construction of implant retained dentures.

Retention in HIV Care During Pregnancy and the Postpartum Period in the Option B+ Era: Systematic Review and Meta-Analysis of Studies in Africa.

Science.gov (United States)

Knettel, Brandon A; Cichowitz, Cody; Ngocho, James Samwel; Knippler, Elizabeth T; Chumba, Lilian N; Mmbaga, Blandina T; Watt, Melissa H

2018-04-15

Under Option B+ guidelines for prevention of mother-to-child transmission of HIV, pregnant and breastfeeding women initiate antiretroviral therapy for lifelong use. The objectives of this study were: (1) to synthesize data on retention in care over time in option B+ programs in Africa, and (2) to identify factors associated with retention in care. PubMed, EMBASE, and African Index Medicus were systematically searched from January 2012 to June 2017. Pooled estimates of the proportion of women retained were generated and factors associated with retention were analyzed thematically. Thirty-five articles were included in the final review; 22 reported retention rates (n = 60,890) and 25 reported factors associated with retention. Pooled estimates of retention were 72.9% (95% confidence interval: 66.4% to 78.9%) at 6 months for studies reporting option B+ were below those of the general adult population, necessitating interventions targeting the complex circumstances of women initiating care under option B+. Improved and standardized procedures to track and report retention are needed to accurately represent care engagement and capture undocumented transfers within the health system.

The relationship between healthy work environments and retention of nurses in a hospital setting.

Science.gov (United States)

Ritter, Desiree

2011-01-01

The purpose of the present paper was to determine the effect a healthy work environment has on the retention of nurses in a hospital setting. There is a nursing shortage that has been ongoing and is expected to continue, resulting in challenges for the healthcare system in the United States. The significance of this issue is the impact the nursing shortage will have on healthcare organizations and patients. The present paper included an extensive review of the current literature. The literature reviewed encompassed scholarly peer-reviewed journal articles. This article focused on nurses, work environments and the impact of the work environments on retention. Important issues that emerged from this analysis were the dangers of an unhealthy environment, the impact a healthy work environment has on patient outcomes and retention, the Magnet link to healthy work environments and the manager's role in creating and sustaining a healthy work environment. The literature provided evidence of the link between healthy work environments and the retention of nurses in a hospital setting. The implications for management are to implement changes now to create a healthy work environment that will recruit and retain nurses to secure their position in the future. © 2010 The Author. Journal compilation © 2010 Blackwell Publishing Ltd.

Functional characterisation of an intron retaining K+ transporter of barley reveals intron-mediated alternate splicing

KAUST Repository

Shahzad, K.

2015-01-01

Intron retention in transcripts and the presence of 5 and 3 splice sites within these introns mediate alternate splicing, which is widely observed in animals and plants. Here, functional characterisation of the K+ transporter, HvHKT2;1, with stably retained introns from barley (Hordeum vulgare) in yeast (Saccharomyces cerevisiae), and transcript profiling in yeast and transgenic tobacco (Nicotiana tabacum) is presented. Expression of intron-retaining HvHKT2;1 cDNA (HvHKT2;1-i) in trk1, trk2 yeast strain defective in K+ uptake restored growth in medium containing hygromycin in the presence of different concentrations of K+ and mediated hypersensitivity to Na+. HvHKT2;1-i produces multiple transcripts via alternate splicing of two regular introns and three exons in different compositions. HKT isoforms with retained introns and exon skipping variants were detected in relative expression analysis of (i) HvHKT2;1-i in barley under native conditions, (ii) in transgenic tobacco plants constitutively expressing HvHKT2;1-i, and (iii) in trk1, trk2 yeast expressing HvHKT2;1-i under control of an inducible promoter. Mixed proportions of three HKT transcripts: HvHKT2;1-e (first exon region), HvHKT2;1-i1 (first intron) and HvHKT2;1-i2 (second intron) were observed. The variation in transcript accumulation in response to changing K+ and Na+ concentrations was observed in both heterologous and plant systems. These findings suggest a link between intron-retaining transcripts and different splice variants to ion homeostasis, and their possible role in salt stress.

Job embeddedness: a theoretical foundation for developing a comprehensive nurse retention plan.

Science.gov (United States)

Holtom, Brooks C; O'Neill, Bonnie S

2004-05-01

Using a new construct, job embeddedness, from the business management literature, this study first examines its value in predicting employee retention in a healthcare setting and second, assesses whether the factors that influence the retention of nurses are systematically different from those influencing other healthcare workers. The shortage of skilled healthcare workers makes it imperative that healthcare providers develop effective recruitment and retention plans. With nursing turnover averaging more than 20% a year and competition to hire new nurses fierce, many administrators rightly question whether they should develop specialized plans to recruit and retain nurses. A longitudinal research design was employed to assess the predictive validity of the job embeddedness concept. At time 1, surveys were mailed to a random sample of 500 employees of a community-based hospital in the Northwest region of the United States. The survey assessed personal characteristics, job satisfaction, organizational commitment, job embeddedness, job search, perceived alternatives, and intent to leave. One year later (time 2) the organization provided data regarding voluntary leavers from the hospital. Hospital employees returned 232 surveys, yielding a response rate of 46.4 %. The results indicate that job embeddedness predicted turnover over and beyond a combination of perceived desirability of movement measures (job satisfaction, organizational commitment) and perceived ease of movement measures (job alternatives, job search). Thus, job embeddedness assesses new and meaningful variance in turnover in excess of that predicted by the major variables included in almost all the major models of turnover. The findings suggest that job embeddedness is a valuable lens through which to evaluate employee retention in healthcare organizations. Further, the levers for influencing retention are substantially similar for nurses and other healthcare workers. Implications of these findings and

Do Developmental Mathematics Programs Have a Causal Impact on Student Retention? An Application of Discrete-Time Survival and Regression-Discontinuity Analysis

Science.gov (United States)

Lesik, Sally A.

2007-01-01

The impact of academic programs--such as developmental mathematics programs--on student retention, has been a controversial topic for administrators, policy makers, and faculty in higher education. Despite deep interest in the effectiveness of these programs in retaining students, scholars have been unable to determine whether such programs have a…

Efficient Work Team Scheduling: Using Psychological Models of Knowledge Retention to Improve Code Writing Efficiency

Directory of Open Access Journals (Sweden)

Michael J. Pelosi

2014-12-01

Full Text Available Development teams and programmers must retain critical information about their work during work intervals and gaps in order to improve future performance when work resumes. Despite time lapses, project managers want to maximize coding efficiency and effectiveness. By developing a mathematically justified, practically useful, and computationally tractable quantitative and cognitive model of learning and memory retention, this study establishes calculations designed to maximize scheduling payoff and optimize developer efficiency and effectiveness.

Retention in a public health care system with free access to treatment

DEFF Research Database (Denmark)

Helleberg, Marie; Engsig, Frederik N; Kronborg, Gitte

2012-01-01

were retained in care 95.0% of person-years under observation, increasing to 98.1% after initiation of antiretroviral treatment (HAART). The overall IR/100 person-years for first episode of LTFU was 2.6 (95% CI: 2.5-2.8) and was significantly lower after initiation of HAART (1.2 (95% CI: 1......, especially after initiation of HAART. Absence from HIV care is associated with increased mortality. We conclude that high rates of retention can be achieved in a health care system with free access to treatment and is associated with a favorable outcome....

Retention of nitrous gases in scrubber columns

International Nuclear Information System (INIS)

Nakazone, A.K.; Costa, R.C.; Lobao, A.S.T.; Matsuda, H.T.; Araujo, B.F. de

1988-01-01

During the UO 2 dissolution in nitric acid, some different species of NO (sub)x are released. The off gas can either be refluxed to the dissolver or be released and retained on special colums. The final composition of the solution is the main parameter to take in account. A process for nitrous gases retention using scrubber colums containing H 2 O or diluted HNO 3 is presented. Chemiluminescence measurement was employed to NO x evaluation before and after scrubing. Gas flow, temperature, residence time are the main parameters considered in this paper. For the dissolution of 100g UO 2 in 8M nitric acid, a 6NL/h O 2 flow was the best condition for the NO/NO 2 oxidation with maximum absorption in the scrubber columns. (author) [pt

9 CFR 441.10 - Retained water.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Retained water. 441.10 Section 441.10... STANDARDS: RAW PRODUCTS § 441.10 Retained water. (a) Raw livestock and poultry carcasses and parts will not be permitted to retain water resulting from post-evisceration processing unless the establishment...

Customer retention: maintaining the competitive edge in the retail market

Energy Technology Data Exchange (ETDEWEB)

Wright, T. [CitiPower Ltd., Melbourne, VIC (Australia)

1997-09-01

The current market environment in the electricity industry is one of changing regulations with many of the rules being developed. There is a great deal of customer confusion and uncertainty with some customers unaware of their contestable status and many are insecure about mixing retail and distribution supplies. This paper discusses customer retention and maintaining the competitive edge in the retail market. It draws on some conclusions from a survey released by the Australian Chamber of Manufacturers entitled `Customer feedback on Victoria`s competitive electricity market`. An overview is presented of the retail market in Australia which is one of very strong price-based competition, with as yet little differentiation. A process is described for retaining customers which involves asking the customer what he/she wants in a language which they understand. The best way to determine customer needs is through a combination of internal and external sources. Enhancing customer loyalty and differentiating and marketing the product are also discussed. As the market matures, customer retention and satisfaction will be based on value added services at a reasonable cost. (author). 6 figs.

Initial soil respiration response to biomass harvesting and green-tree retention in aspen-dominated forests of the Great Lakes region

Science.gov (United States)

Kurth, Valerie J.; Bradford, John B.; Slesak, Robert A.; D'Amato, Anthony W.

2014-01-01

Contemporary forest management practices are increasingly designed to optimize novel objectives, such as maximizing biomass feedstocks and/or maintaining ecological legacies, but many uncertainties exist regarding how these practices influence forest carbon (C) cycling. We examined the responses of soil respiration (Rs) to biomass harvesting and green-tree retention in an effort to empirically assess their impacts on C cycling. We measured Rs and soil microclimatic variables over four growing seasons following implementation of these management practices using a fully replicated, operational-scale experiment in aspen-dominated forests in northern Minnesota. Treatments included three levels of biomass removal within harvested areas: whole-tree harvest (no slash deliberately retained), 20% slash retained, and stem-only harvest (all slash retained), and two levels of green-tree retention: 0.1 ha aggregate or none. The relative amount of biomass removed had a negligible effect on Rs in harvested areas, but treatment effects were probably obscured by heterogeneous slash configurations and rapid post-harvest regeneration of aspen in all of the treatments. Discrete measurements of Rs and soil temperature within green-tree aggregates were not discernible from surrounding harvested areas or unharvested control stands until the fourth year following harvest, when Rs was higher in unharvested controls than in aggregates and harvested stands. Growing season estimates of Rs showed that unharvested control stands had higher Rs than both harvested stands and aggregates in the first and third years following harvest. Our results suggest that retention of larger forest aggregates may be necessary to maintain ecosystem-level responses similar to those in unharvested stands. Moreover, they highlight the innate complexity of operational-scale research and suggest that the initial impacts of biomass harvest on Rs may be indiscernible from traditional harvest in systems where incidental

Retention and reduction of uranium on pyrite surface

International Nuclear Information System (INIS)

Eglizaud, N.

2006-12-01

In the hypothesis of a storage of the spent fuel in a deep geological formation, understanding the uranium dispersion in the environment is important. Pyrite is a reducing mineral present in the Callovo-Oxfordian argilites, the geological formation actually studied for such a storage. However, pyrite impact on uranium migration has already been poorly studied. The aim of the study was to understand the mechanisms of uranium(VI) retention and reduction on the pyrite surface (FeS 2 ). Solution chemistry was therefore coupled with solid spectroscopic studies (XPS and Raman spectroscopy). All uranium-pyrite interactions experiments were performed under an anoxic atmosphere, in a glove box. Pyrite dissolution under anoxic conditions releases sulfoxy-anions and iron(II), which can then be adsorbed on the pyrite surface. This adsorption was confirmed by interaction experiments using iron(II) isotopic dilution. Uranium(VI) is retained by an exchange reaction with iron(II) adsorbed on sulphur sites, with a maximal amount of sorbed uranium at pH ≥ 5.5. Cobalt(II) and europium(III) are also adsorbed on the pyrite surface above pH 5.5 confirming then that reduction is not required for species to adsorb on pyrite. When the concentration of uranium retained is lower than 4 x 10 -9 mol g -1 , an oxidation-reduction reaction leads to the formation of a uranium (VI) (IV) mixed oxide and to solid sulphur (d.o. ≥ -I). During this reaction, iron remains mostly at the +II oxidation degree. The reaction products seem to passivate the pyrite surface: at higher amounts of retained uranium, the oxidation-reduction reaction is no longer observed. The surface is saturated by the retention of (3.4 ± 0.8) x 10 -7 mol L -1 of uranium(VI). Modelling of uranium sorption at high surface coverage (≥ 4 x 10 -9 mol g -1 ) by the Langmuir model yields an adsorption constant of 8 x 10 7 L mol -1 . Finally, a great excess of uranium(VI) above the saturation concentration allows the observation of

Comparison of Stability of the Results of Orthodontic Treatment and Gingival Health between Hawley and Vacuum-formed Retainers.

Science.gov (United States)

Moslemzadeh, Seyed H; Sohrabi, Aydin; Rafighi, Ali; Farshidnia, Somaieh

2018-04-01

Aim: Retention is one of the stages of orthodontic treatment, which is an attempt to retain teeth in their corrected positions after active treatment with the use of fixed orthodontic appliances. The aim of the present study was to compare the stability of the results of orthodontic treatment and the gingival health between Hawley retainer (HR) and vacuum-formed retainer (VFR) with two different thicknesses. Materials and methods: In this randomized clinical trial, 66 patients undergoing comprehensive orthodontic treatment in a private office were evaluated after completion of treatment. The subjects were randomly assigned to three groups. At the end of orthodontic treatment, the subjects in all the groups received a fixed bonded retainer in the mandible; in the maxilla, group I received an HR, group II received a VFR with a thickness of 1.5 mm, and group III received a VFR with a thickness of 1 mm. The American Board of Orthodontics objective grading system (ABO-OGS) index was used at the end of treatment (before the delivery of the retainers) and 6 months after the use of retainers to evaluate the stability of the results of orthodontic treatment. Gingival index (GI) was used at the two above-mentioned intervals to evaluate gingival health. The ABO-OGS measurements were carried out on dental casts by a clinician who was blinded to the types of retainers the patients wore. Data were analyzed with Statistical Package for the Social Sciences (SPSS) version 20, using proper statistical analyses. Results: Six months after the delivery of retainers, ABO-OGS and GI scores with the 1.5 mm VFR were higher than those in the two other groups, with no significant differences between the three groups. There were no significant differences between the ABO-OGS scores before the delivery of retainers and 6 months after the use of retainers in any of the study groups. In the HR and 1.5 mm VFR groups, there were significant differences in GI scores between the period before the

Nicotine delivery, retention and pharmacokinetics from various electronic cigarettes.

Science.gov (United States)

St Helen, Gideon; Havel, Christopher; Dempsey, Delia A; Jacob, Peyton; Benowitz, Neal L

2016-03-01

To measure the systemic retention of nicotine, propylene glycol (PG) and vegetable glycerin (VG) in electronic cigarette (e-cigarette) users, and assess the abuse liability of e-cigarettes by characterizing nicotine pharmacokinetics. E-cigarette users recruited over the internet participated in a 1-day research ward study. Subjects took 15 puffs from their usual brand of e-cigarette. Exhaled breath was trapped in gas-washing bottles and blood was sampled before and several times after use. San Francisco, California, USA. Thirteen healthy, experienced adult e-cigarette users (six females and seven males). Plasma nicotine was analyzed by gas chromatography-mass spectrometry (GC-MS/MS) and nicotine, VG and PG in e-liquids and gas traps were analyzed by LC-MS/MS. Heart rate changes and subjective effects were assessed. E-cigarettes delivered an average of 1.33 (0.87-1.79) mg [mean and 95% confidence interval (CI)] of nicotine, and 93.8% of the inhaled dose, 1.22 (0.80-1.66) was systemically retained. Average maximum plasma nicotine concentration (Cmax ) was 8.4 (5.4-11.5) ng/ml and time of maximal concentration (Tmax ) was 2-5 minutes. One participant had Tmax of 30 minutes. 84.4% and 91.7% of VG and PG, respectively, was systemically retained. Heart rate increased by an average of 8.0 beats per minute after 5 minutes. Withdrawal and urge to smoke decreased and the e-cigarettes were described as satisfying. E-cigarettes can deliver levels of nicotine that are comparable to or higher than typical tobacco cigarettes, with similar systemic retention. Although the average maximum plasma nicotine concentration in experienced e-cigarette users appears to be generally lower than what has been reported from tobacco cigarette use, the shape of the pharmacokinetic curve is similar, suggesting addictive potential. © 2015 Society for the Study of Addiction.

Computed Tomographic-Guided Radiofrequency Ablation of Recurrent or Residual Hepatocellular Carcinomas around Retained Iodized Oil after Transarterial Chemoembolization

Energy Technology Data Exchange (ETDEWEB)

Koh, Young Hwan [Center for Liver Cancer, National Cancer Center, Goyang 410-769 (Korea, Republic of); Department of Radiology, Research Institute and Hospital, National Cancer Center, Goyang 410-769 (Korea, Republic of); Choi, Joon-Il [Center for Liver Cancer, National Cancer Center, Goyang 410-769 (Korea, Republic of); Department of Radiology, Research Institute and Hospital, National Cancer Center, Goyang 410-769 (Korea, Republic of); Department of Radiology, Seoul St. Mary' s Hospital, College of Medicine, The Catholic University of Korea, Seoul 137-701 (Korea, Republic of); Kim, Hyun Beom [Center for Liver Cancer, National Cancer Center, Goyang 410-769 (Korea, Republic of); Department of Radiology, Research Institute and Hospital, National Cancer Center, Goyang 410-769 (Korea, Republic of); Kim, Min Ju [Department of Radiology, Research Institute and Hospital, National Cancer Center, Goyang 410-769 (Korea, Republic of)

2013-07-01

To assess the clinical efficacy, safety, and risk factors influencing local tumor progression, following CT-guided radiofrequency ablation (RFA) of recurrent or residual hepatocellular carcinoma (HCC), around iodized oil retention. Sixty-four patients (M : F = 51 : 13, 65.0 ± 8.2 years old) with recurrent or residual HCC (75 index tumors, size = 14.0 ± 4.6 mm) had been treated by CT-guided RFA, using retained iodized oil as markers for targeting. The technical success, technique effectiveness rate and complications of RFA were then assessed. On pre-ablative and immediate follow-up CT after RFA, we evaluated the size of enhancing index tumors and iodized oil retention, presence of abutting vessels, completeness of ablation of iodized oil retention, and the presence of ablative margins greater than 5 mm. Also, the time interval between transarterial chemoembolization and RFA was assessed. The cumulative local tumor progression rate was calculated using the Kaplan-Meier method, and the Cox proportional hazards model was adopted, to clarify the independent factors affecting local tumor progression. The technical success and technique effectiveness rate was 100% and 98.7%, respectively. Major complications were observed in 5.6%. The cumulative rates of local tumor progression at 1 and 2 years were 17.5% and 37.5%, respectively. In multivariate analyses, partial ablation of the targeted iodized oil retention was the sole independent predictor of a higher local tumor progression rate. CT-guided RFA of HCC around iodized oil retention was effective and safe. Local tumor progression can be minimized by complete ablation of not only index tumors, but targeted iodized oil deposits as well.

Retention and reduction of uranium on pyrite surface; Retention et reduction de l'uranium a la surface de la pyrite

Energy Technology Data Exchange (ETDEWEB)

Eglizaud, N

2006-12-15

In the hypothesis of a storage of the spent fuel in a deep geological formation, understanding the uranium dispersion in the environment is important. Pyrite is a reducing mineral present in the Callovo-Oxfordian argilites, the geological formation actually studied for such a storage. However, pyrite impact on uranium migration has already been poorly studied. The aim of the study was to understand the mechanisms of uranium(VI) retention and reduction on the pyrite surface (FeS{sub 2}). Solution chemistry was therefore coupled with solid spectroscopic studies (XPS and Raman spectroscopy). All uranium-pyrite interactions experiments were performed under an anoxic atmosphere, in a glove box. Pyrite dissolution under anoxic conditions releases sulfoxy-anions and iron(II), which can then be adsorbed on the pyrite surface. This adsorption was confirmed by interaction experiments using iron(II) isotopic dilution. Uranium(VI) is retained by an exchange reaction with iron(II) adsorbed on sulphur sites, with a maximal amount of sorbed uranium at pH {>=} 5.5. Cobalt(II) and europium(III) are also adsorbed on the pyrite surface above pH 5.5 confirming then that reduction is not required for species to adsorb on pyrite. When the concentration of uranium retained is lower than 4 x 10{sup -9} mol g{sup -1}, an oxidation-reduction reaction leads to the formation of a uranium (VI) (IV) mixed oxide and to solid sulphur (d.o. {>=} -I). During this reaction, iron remains mostly at the +II oxidation degree. The reaction products seem to passivate the pyrite surface: at higher amounts of retained uranium, the oxidation-reduction reaction is no longer observed. The surface is saturated by the retention of (3.4 {+-} 0.8) x 10{sup -7} mol L{sup -1} of uranium(VI). Modelling of uranium sorption at high surface coverage ({>=} 4 x 10{sup -9} mol g{sup -1}) by the Langmuir model yields an adsorption constant of 8 x 10{sup 7} L mol{sup -1}. Finally, a great excess of uranium(VI) above the

Inlay-Retained Fixed Dental Prosthesis: A Clinical Option Using Monolithic Zirconia

Directory of Open Access Journals (Sweden)

Davide Augusti

2014-01-01

Full Text Available Different indirect restorations to replace a single missing tooth in the posterior region are available in dentistry: traditional full-coverage fixed dental prostheses (FDPs, implant-supported crowns (ISC, and inlay-retained FDPs (IRFDP. Resin bonded FDPs represent a minimally invasive procedure; preexisting fillings can minimize tooth structure removal and give retention to the IRFDP, transforming it into an ultraconservative option. New high strength zirconia ceramics, with their stiffness and high mechanical properties, could be considered a right choice for an IRFDP rehabilitation. The case report presented describes an IRFDP treatment using a CAD/CAM monolithic zirconia IRFDP; clinical and laboratory steps are illustrated, according to the most recent scientific protocols. Adhesive procedures are focused on the Y-TZP and tooth substrate conditioning methods. Nice esthetic and functional integration of indirect restoration at two-year follow-up confirmed the success of this conservative approach.

Grass plants bind, retain, uptake, and transport infectious prions.

Science.gov (United States)

Pritzkow, Sandra; Morales, Rodrigo; Moda, Fabio; Khan, Uffaf; Telling, Glenn C; Hoover, Edward; Soto, Claudio

2015-05-26

Prions are the protein-based infectious agents responsible for prion diseases. Environmental prion contamination has been implicated in disease transmission. Here, we analyzed the binding and retention of infectious prion protein (PrP(Sc)) to plants. Small quantities of PrP(Sc) contained in diluted brain homogenate or in excretory materials (urine and feces) can bind to wheat grass roots and leaves. Wild-type hamsters were efficiently infected by ingestion of prion-contaminated plants. The prion-plant interaction occurs with prions from diverse origins, including chronic wasting disease. Furthermore, leaves contaminated by spraying with a prion-containing preparation retained PrP(Sc) for several weeks in the living plant. Finally, plants can uptake prions from contaminated soil and transport them to aerial parts of the plant (stem and leaves). These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Guidewire retention following central venous catheterisation: a human factors and safe design investigation.

Science.gov (United States)

Horberry, Tim; Teng, Yi-Chun; Ward, James; Patil, Vishal; Clarkson, P John

2014-01-01

Central Venous Catheterisation (CVC) has occasionally been associated with cases of retained guidewires in patients after surgery. In theory, this is a completely avoidable complication; however, as with any human procedure, operator error leading to guidewires being occasionally retained cannot be fully eliminated. The work described here investigated the issue in an attempt to better understand it both from an operator and a systems perspective, and to ultimately recommend appropriate safe design solutions that reduce guidewire retention errors. Nine distinct methods were used: observations of the procedure, a literature review, interviewing CVC end-users, task analysis construction, CVC procedural audits, two human reliability assessments, usability heuristics and a comprehensive solution survey with CVC end-users. The three solutions that operators rated most highly, in terms of both practicality and effectiveness, were: making trainees better aware of the potential guidewire complications and strongly emphasising guidewire removal in CVC training, actively checking that the guidewire is present in the waste tray for disposal, and standardising purchase of central line sets so that differences that may affect chances of guidewire loss is minimised. Further work to eliminate/engineer out the possibility of guidewires being retained is proposed.

Strategies to improve retention in randomised trials

Science.gov (United States)

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

2013-01-01

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

Observations of suppressed retention and blistering for tungsten exposed to deuterium-helium mixture plasmas

International Nuclear Information System (INIS)

Miyamoto, M.; Morito, S.; Ono, K.; Nishijima, D.; Doerner, R.P.; Baldwin, M.J.; Hanna, J.; Ueda, Y.; Kurishita, H.

2009-01-01

Blister formation and D retention in W have been investigated for low energy (∼55 ± 15 eV), high flux (∼10 22 m -2 s -1 ), high fluence (≤4.5 x 10 26 m -2 ) ion bombardment at moderate temperature (∼573 K) in mixed species D+He plasmas in the linear divertor plasma simulator PISCES-A. The amount of D retained in W is found to decrease significantly when compared with that in W exposed to pure D plasmas, as measured with high resolution thermal desorption spectroscopy. Scanning electron microscopy observations reveal the suppression of the blisters, a surface feature known to drive up retention, in the D + He mixture plasma exposed W samples. Reduced D retention is accompanied by the formation of nano-sized high density He bubbles in the near surface, observed with a transmission electron microscope (TEM). It is believed that the nano-bubbles act as a diffusion barrier to implanted D atoms and consequently reduce the amount of uptake in the W material. This newly observed effect implies that current predictions of D retention in W, in actual fusion devices, may be overestimated, since there will be He ash in fusion plasma. Toughness enhanced, fine-grained (grain size of ∼1 μm) W-TiC samples, exposed to pure D plasma conditions, also show little or no evidence of blistering. The measured D retention in the W-TiC samples was approximately 1 x 10 19 D m -2 corresponding to about 2 x 10 -7 of the implanted D fluence, and is very low compared with the retention in pure stress relieved W, which exhibited surface blisters and had a D retention of about 1 x 10 21 D m -2 .

The value of animations in biology teaching: a study of long-term memory retention.

Science.gov (United States)

O'Day, Danton H

2007-01-01

Previous work has established that a narrated animation is more effective at communicating a complex biological process (signal transduction) than the equivalent graphic with figure legend. To my knowledge, no study has been done in any subject area on the effectiveness of animations versus graphics in the long-term retention of information, a primary and critical issue in studies of teaching and learning. In this study, involving 393 student responses, three different animations and two graphics-one with and one lacking a legend-were used to determine the long-term retention of information. The results show that students retain more information 21 d after viewing an animation without narration compared with an equivalent graphic whether or not that graphic had a legend. Students' comments provide additional insight into the value of animations in the pedagogical process, and suggestions for future work are proposed.

Forms of newly retained phosphorus in mineral soils

Directory of Open Access Journals (Sweden)

Armi Kaila

1964-01-01

Full Text Available The distribution of soluble phosphate in various fractions of soil phosphorus was studied by treating 1 g-samples of 180 mineral soils with 50 ml of a KH2PO4- solution containing P 5 mg/l for 24 hours, and carrying out the fractionation by the method of CHANG and JACKSON after the solution was removed and the moist samples had stood for 3 days at room temperature. The amount of retained phosphorus in the different fractions was computed by taking the difference between the treated and check samples. In the 70 samples of clay soils, the mean proportion of the retained phosphorus was 57 per cent of the 250 mg/kg applied, in the 62 samples of the sand and fine sand soils the corresponding part was 45 per cent, and in the 48 samples of loam and silt soils it was 44 per cent. The higher retention in the clay soils was mainly due to a higher retention in the alkali-soluble fraction. The net increase in the fluoride-soluble forms was of the same order in these three soil groups. On the average, more than 95 per cent of the sorbed phosphorus was found in the fluoride-soluble and alkali-soluble fractions. In one third of the samples a low net increase in the acid soluble fraction was detected, but this may be partly due to changes in the solubility of the native phosphorus in the treated samples. Owing to the fairly large variation, the tendency to somewhat higher mean values for the sorption in the subsoils compared with those of the topsoils was not statistically significant. The ratio between the sorbed amounts of fluoride-soluble and alkali soluble forms was higher in the sand and fine sand soils than in the clay soils. Only in 15 samples, most of them Litorina-soils, the net increase in the alkali-soluble forms was higher than in the fluoride-soluble fraction. Probably, because an equilibrium in the phosphorus conditions was not yet reached at the end of the treatment, the attempt failed to find any clear connection between the distribution of the

Quantifying retention during pre-antiretroviral treatment in a large urban clinic in Uganda.

Science.gov (United States)

Castelnuovo, Barbara; Musaazi, Joseph; Musomba, Rachel; Ratanshi, Rosalind Parkes; Kiragga, Agnes N

2015-07-01

Retention studies are usually focused on patients on antiretroviral treatment (ART), however in Sub-Saharan Africa many patients get lost to program (LTP) in the pre-ART care period.. We investigated the proportion of patients not retained in care and factors associated with LTP (dead or lost to follow up ≥6 months) in the pre-ART care period. We analyzed data from the Infectious Diseases Institute, Kampala, Uganda. We included all adult patients ≥18 years, ART naïve at program enrollment from 1(st)/Jan/2005. We described the number of patients not retained in care during the 3 steps of enrollment-to-treatment "cascade": Step 1) From enrollment to CD4 count testing, Step 2) ART eligibility assessment. Patients were initially considered eligible if CD4 count was ART start. We described cumulative probability of being LTP by gender and ART eligibility using Kaplan Meier estimates. We used a Cox proportional hazards model to identify factors associated with being LTP at any stage for all patients and for those with a CD4 count available. Factors considered were age, gender, year of enrollment, and WHO stage. After enrollment in our program, cumulatively, a low proportion of patients (30.8 %) were retained and started on ART. The cumulative probability of being LTP was higher in males and patients not eligible for ART. In the multivariable Cox proportional Hazards model, male gender (HR: 1.19 CI 1.12-1.19) and clinical WHO stage 3 and 4 (HR: 1.20 CI 1.13-1.27) were associated with being LTP while older age was protective (HR: 0.98 0.96-0.99). Patients enrolled in the program more recently were also at lower risk of being LTP. In addition, among patients with CD4 count test, patients with higher CD4 count were at higher risk of being LTP. In our program there has been suboptimal retention of patients in pre-ART care, particularly of patients not eligible for ART. Since the proportion of eligible patients has recently increased due to the higher recommended

Impacts of post-harvest slash and live-tree retention on biomass and nutrient stocks in Populus tremuloides Michx.-dominated forests, northern Minnesota, USA

Science.gov (United States)

Klockow, Paul A.; D'Amato, Anthony W.; Bradford, John B.

2013-01-01

Globally, there is widespread interest in using forest-derived biomass as a source of bioenergy. While conventional timber harvesting generally removes only merchantable tree boles, harvesting biomass feedstock can remove all forms of woody biomass (i.e., live and dead standing woody vegetation, downed woody debris, and stumps) resulting in a greater loss of biomass and nutrients as well as more severe habitat alteration. To investigate the potential impacts of this practice, this study examined the initial impacts (pre- and post-harvest) of various levels of slash and live-tree retention on biomass and nutrient stocks, including carbon (C), nitrogen (N), calcium (Ca), potassium (K), and phosphorus (P), in Populus tremuloides Michx.-dominated forests of northern Minnesota, USA. Treatments examined included three levels of slash retention, whole-tree harvest (WTH), 20% slash retention (20SR), and stem-only harvest (SOH), factored with three levels of green-tree retention, no trees retained (NONE), dispersed retention (DISP), and aggregate retention (AGR). Slash retention was the primary factor affecting post-harvest biomass and nutrient stocks, including woody debris pools. Compared to the unharvested control, stocks of biomass, carbon, and nutrients, including N, Ca, K, and P, in woody debris were higher in all treatments. Stem-only harvests typically contained greater biomass and nutrient stocks than WTH, although biomass and nutrients within 20SR, a level recommended by biomass harvesting guidelines in the US and worldwide, generally did not differ from WTH or SOH. Biomass in smaller-diameter slash material (typically 2.5-22.5 cm in diameter) dominated the woody debris pool following harvest regardless of slash retention level. Trends among treatments in this diameter range were generally similar to those in the total woody debris pool. Specifically, SOH contained significantly greater amounts of biomass than WTH while 20SR was not different from either WTH or

Kinetics of the fixation of carbon monoxide in the blood. III. Dose received and dose retained: significance of pollution peaks

Energy Technology Data Exchange (ETDEWEB)

Chovin, P.

1974-01-01

The kinetics of the retention of carbon monoxide in the blood is discussed with respect to certain CO concentration standards. The ratio of the amount of CO retained by the blood to the amount inhaled is independent of the CO concentration in the inhaled air and increases with decreasing exposure time. An exposure to 50 ppM CO for 8 hr causes a carboxyhemoglobin level of 5.5 percent, corresponding to a retention rate of 31.5 percent, while exposure to the same concentration for 30 min results in a retention rate of 55 percent. With the dose inhaled being constant, the COHb level varies as a function of time, increasing with shortening of the exposure time, which emphasizes the hazards of high CO peaks in street air. Exposure to 40 ppM CO for 1 hr and to 10 ppM CO for 12 hr according to the California standard will result increases in the COHb level by 0.93 percent and 1.3 percent, respectively. The inconsistency of U.S. standards is further demonstrated by the great divergence between the safety factors calculated for exposure to the maximum allowable concentrations for the respective maximum allowable durations.

Composition and quantities of retained gas measured in Hanford waste tanks 241-U-103, S-106, BY-101, and BY-109

Energy Technology Data Exchange (ETDEWEB)

Mahoney, L.A.; Antoniak, Z.I.; Bates, J.M.

1997-12-01

This report provides the results obtained for the single-shell tanks (SSTs) sampled with the Retained Gas Sampler (RGS) during 1997: Tanks 241-U-103, 241-S-106, 241-BY-101, and 241-BY-109. The RGS is a modified version of the core sampler used at Hanford. It is designed specifically to be used in concert with the gas extraction equipment in the hot cell to capture and extrude a gas-containing waste sample in a hermetically sealed system. The four tanks represent several different types of flammable gas SSTs. Tank U-103 is on the Flammable Gas Watch List (FGWL) and is one of the highest-priority group of SSTs that show evidence of significant gas retention. Tank S-106, though not a FGWL tank, has a uniquely high barometric pressure response and continuing rapid surface level rise, indicating a large and increasing volume of retained gas. Tanks BY-101 and BY-109 are not on the FGWL but were chosen to test the effect of recent salt-well pumping on gas retention. Section 2 of this report provides an overview of the process by which retained gases in the Hanford tanks are sampled and analyzed. A detailed description of the procedure used to reduce and analyze the data is provided in Section 3. Tank-by-tank results are covered in Section 4 (with the data presented in the order in which the tanks were sampled), and an RGS system performance overview is given in Section 5. Section 6 presents conclusions from these analyses and recommendations for further research. The cited references are listed in Section 7. Appendix A describes the procedures used to extract gas and ammonia from the samples, Appendix B contains detailed laboratory data from each of the tanks, and Appendix C gives field sampling data.

Composition and quantities of retained gas measured in Hanford waste tanks 241-U-103, S-106, BY-101, and BY-109

International Nuclear Information System (INIS)

Mahoney, L.A.; Antoniak, Z.I.; Bates, J.M.

1997-12-01

This report provides the results obtained for the single-shell tanks (SSTs) sampled with the Retained Gas Sampler (RGS) during 1997: Tanks 241-U-103, 241-S-106, 241-BY-101, and 241-BY-109. The RGS is a modified version of the core sampler used at Hanford. It is designed specifically to be used in concert with the gas extraction equipment in the hot cell to capture and extrude a gas-containing waste sample in a hermetically sealed system. The four tanks represent several different types of flammable gas SSTs. Tank U-103 is on the Flammable Gas Watch List (FGWL) and is one of the highest-priority group of SSTs that show evidence of significant gas retention. Tank S-106, though not a FGWL tank, has a uniquely high barometric pressure response and continuing rapid surface level rise, indicating a large and increasing volume of retained gas. Tanks BY-101 and BY-109 are not on the FGWL but were chosen to test the effect of recent salt-well pumping on gas retention. Section 2 of this report provides an overview of the process by which retained gases in the Hanford tanks are sampled and analyzed. A detailed description of the procedure used to reduce and analyze the data is provided in Section 3. Tank-by-tank results are covered in Section 4 (with the data presented in the order in which the tanks were sampled), and an RGS system performance overview is given in Section 5. Section 6 presents conclusions from these analyses and recommendations for further research. The cited references are listed in Section 7. Appendix A describes the procedures used to extract gas and ammonia from the samples, Appendix B contains detailed laboratory data from each of the tanks, and Appendix C gives field sampling data

What fraction of the total metal flux into lakes is retained in the sediments

Energy Technology Data Exchange (ETDEWEB)

Nriagu, J O; Wong, H K.T.

1986-12-01

The concentrations of, and deposition rates for, the pollutant metals (Pb, Cu, Zn, Ni, and Cd) and the rare earth elements are reported for the sediments and settling particulates in a large, remote lake (Lake Opeongo) in the Algonquin Provincial Park, Ontario. Using a mass conservation model based on the rare earth elements, it is estimated that only 40 to 60% of pollutant metals getting into the lake is retained by the sediments. The low retention rate may explain the widely reported intrabasin and intra-lake differences in metal contents of sediments and casts some doubt on the use of pollutant metal profiles in retrospective assessment of the human contribution to the metal flux into many lake basins. 22 references.

Profit-Based Model Selection for Customer Retention Using Individual Customer Lifetime Values.

Science.gov (United States)

Óskarsdóttir, María; Baesens, Bart; Vanthienen, Jan

2018-03-01

The goal of customer retention campaigns, by design, is to add value and enhance the operational efficiency of businesses. For organizations that strive to retain their customers in saturated, and sometimes fast moving, markets such as the telecommunication and banking industries, implementing customer churn prediction models that perform well and in accordance with the business goals is vital. The expected maximum profit (EMP) measure is tailored toward this problem by taking into account the costs and benefits of a retention campaign and estimating its worth for the organization. Unfortunately, the measure assumes fixed and equal customer lifetime value (CLV) for all customers, which has been shown to not correspond well with reality. In this article, we extend the EMP measure to take into account the variability in the lifetime values of customers, thereby basing it on individual characteristics. We demonstrate how to incorporate the heterogeneity of CLVs when CLVs are known, when their prior distribution is known, and when neither is known. By taking into account individual CLVs, our proposed approach of measuring model performance gives novel insights when deciding on a customer retention campaign. The method is dependent on the characteristics of the customer base as is compliant with modern business analytics and accommodates the data-driven culture that has manifested itself within organizations.

Hydrogen retention in ion irradiated steels

International Nuclear Information System (INIS)

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

1998-01-01

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 + , 1 microm 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 ( 2 H) was injected in place of natural hydrogen ( 1 H) during the implantation. Trapped deuterium was then profiled, at room temperature, using the high cross-section nuclear resonance reaction with 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%

Oxygen plasma treatment of HKUST-1 for porosity retention upon exposure to moisture.

Science.gov (United States)

Bae, Jaeyeon; Jung, Jin-Woo; Park, Hyo Yul; Cho, Chang-Hee; Park, Jinhee

2017-11-07

Despite their remarkable properties, metal-organic frameworks (MOFs) present vulnerable structures that are sensitive to moisture; therefore, their application to real field situations is challenging. Herein, an O 2 plasma technique was introduced as a new method for the activation and protection of porosity in HKUST-1. In an unprecedented manner, O 2 plasma-treated HKUST-1 retains its porosity after a long exposure to moisture as compared to pristine HKUST-1. Porosity retention was examined by N 2 adsorption/desorption measurements of non-activated HKUST-1 after exposure to moisture.

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

Directory of Open Access Journals (Sweden)

Christopher Szota

2017-11-01

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

Diffusive retention of atmospheric gases in chert

Science.gov (United States)

Pettitt, E.; Cherniak, D. J.; Watson, E. B.; Schaller, M. F.

2016-12-01

Throughout Earth's history, the volatile contents (N2, CO2, Ar) of both deep and shallow terrestrial reservoirs has been dynamic. Volatiles are important chemical constituents because they play a significant role in regulating Earth's climate, mediating the evolution of complex life, and controlling the properties of minerals and rocks. Estimating levels of atmospheric volatiles in the deep geological past requires interrogation of materials that have acquired and retained a chemical memory from that time. Cherts have the potential to trap atmospheric components during formation and later release those gases for analysis in the laboratory. However, cherts have been underexploited in this regard, partly because their ability to retain a record of volatile components has not been adequately evaluated. Before cherts can be reliably used as indicators of past levels of major atmospheric gases, it is crucial that we understand the diffusive retentiveness of these cryptocrystalline silica phases. As the first step toward quantifying the diffusivity and solubility of carbon dioxide and nitrogen in chert, we have performed 1-atmosphere diffusive-uptake experiments at temperatures up to 450°C. Depth profiles of in-diffusing gases are measured by nuclear reaction analysis (NRA) to help us understand the molecular-scale transport of volatiles and thus the validity of using chert-bound volatiles to record information about Earth history. Data collected to date suggest that at least some cherts are ideal storage containers and can retain volatiles for a geologically long time. In addition to these diffusion experiments, preliminary online-crush fast-scan measurements using a quadrupole mass spectrometer indicate that atmospheric volatiles are released upon crushing various chert samples. By coupling such volatile-release measurements made by mass spectrometry with diffusion experiments, we are uniquely able to address the storage and fidelity of volatiles bound in crustal

47 CFR 32.4550 - Retained earnings.

Science.gov (United States)

2010-10-01

... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.4550 Retained earnings. (a) This account shall include the undistributed balance of retained earnings derived from the...

The Court of Justice and The Data Retention Directive in Digital Rights Ireland: Telling Off The EU Legislator and Teaching a Lesson in Privacy and Data Protection

NARCIS (Netherlands)

Granger, M.-P.; Irion, K.

2014-01-01

In Digital Rights Ireland, the Court of Justice invalidated the 2006 Data Retention Directive, which required private providers to retain for a considerable period electronic communication metadata for law enforcement purposes. In this landmark ruling, the EU judiciary introduced a strict scrutiny

Apparent mineral retention is similar in control and hyperinsulinemic men after consumption of high amylose cornstarch.

Science.gov (United States)

Behall, Kay M; Howe, Juliette C; Anderson, Richard A

2002-07-01

The effects on apparent mineral retention after long-term consumption of a high amylose diet containing 30 g resistant starch (RS) were investigated in 10 control and 14 hyperinsulinemic men. Subjects consumed products (bread, muffins, cookies, corn flakes and cheese puffs) made with standard (70% amylopectin, 30% amylose; AP) or high amylose (70% amylose, 30% amylopectin; AM) cornstarch for two 14-wk periods in a crossover pattern. Starch products replaced usual starches in the habitual diet for 10 wk followed by 4 wk of consuming the controlled diets. During wk 12, all urine, feces and duplicate foods were collected for 7 d. Urinary chromium losses after a glucose tolerance test or 24-h collections of the hyperinsulinemic and control subjects did not differ and were not altered by diet. Except for zinc, the two subject types did not differ significantly in apparent mineral balance. Apparent retentions of calcium and magnesium were not significantly affected by diet (AM vs. AP) or type-by-diet interaction. Apparent iron retention tended to be greater after AM than AP consumption (P copper retention was greater after consuming AP than after AM (P < 0.02), whereas apparent zinc retention was greater after consuming AM than after AP (P < 0.018). Zinc also showed a significant type-by-diet interaction (P < 0.034) with control subjects retaining less zinc after consuming AP than after AM. In summary, a high amylose cornstarch diet containing 30 g RS could be consumed long term without markedly affecting, and possibly enhancing, retention of some minerals.

The Effect of Inhalation Volume and Breath-Hold Duration on the Retention of Nicotine and Solanesol in the Human Respiratory Tract and on Subsequent Plasma Nicotine Concentrations During Cigarette Smoking

Directory of Open Access Journals (Sweden)

Armitage AK

2014-12-01

Full Text Available The influence of inhalation depth and breath-hold duration on the retention of nicotine and solanesol in the human respiratory tract and on nicotine uptake was studied in ten cigarette smokers. In a first series of experiments, the subjects took seven puffs from a 10 mg ‘tar’ yield, test cigarette and a fixed volume of air (0, 75, 250, 500 or 1000 mL, as required by the protocol was inhaled after each puff in order to give a controlled ‘depth’ of inhalation. The inhalation was drawn from a bag containing the required volume of air. Following a 2 s breath-hold, subjects exhaled normally, with the first exhalation after each puff passing through a single acidified filter pad for collection of the non-retained nicotine and solanesol. Blood samples were taken before and at intervals during and after smoking for the sessions with 0, 75 and 500 mL inhalation volumes for determination of plasma nicotine and carboxyhaemoglobin levels. Another series of experiments was conducted with a fixed inhalation volume (500 mL and two further breath-hold durations (0 and 10 s in addition to 2 s from above. Nicotine and solanesol retentions were measured for each breath-hold condition. The amounts of nicotine retained within the respiratory system, expressed as a percentage of the amount taken into the mouth, were consistently higher than the corresponding values for solanesol in all five inhalation conditions (0-1000 mL, 2 s breath-hold. Nicotine retention increased from 46.5% at zero inhalation to 99.5% at 1000 mL inhalation (2 s breath-hold and from 98.0% at zero breath-hold to 99.9% at 10 s breath-hold (500 mL inhalation. Solanesol retention increased from 34.2% at zero inhalation volume to 71.9% at 1000 mL inhalation (2 s breath-hold and from 51.8% at zero breath-hold to 87.6% at 10 s breath-hold (500 mL inhalation. Plasma nicotine decreased from pre-smoking levels after zero inhalation indicating that the nicotine retained within the mouth was poorly

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

Science.gov (United States)

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

2013-06-06

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

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

Directory of Open Access Journals (Sweden)

Michael N. Pham

2013-04-01

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

Regulation of RNA-binding proteins affinity to export receptors enables the nuclear basket proteins to distinguish and retain aberrant mRNAs.

Science.gov (United States)

Soheilypour, M; Mofrad, M R K

2016-11-02

Export of messenger ribonucleic acids (mRNAs) into the cytoplasm is a fundamental step in gene regulation processes, which is meticulously quality controlled by highly efficient mechanisms in eukaryotic cells. Yet, it remains unclear how the aberrant mRNAs are recognized and retained inside the nucleus. Using a new modelling approach for complex systems, namely the agent-based modelling (ABM) approach, we develop a minimal model of the mRNA quality control (QC) mechanism. Our results demonstrate that regulation of the affinity of RNA-binding proteins (RBPs) to export receptors along with the weak interaction between the nuclear basket protein (Mlp1 or Tpr) and RBPs are the minimum requirements to distinguish and retain aberrant mRNAs. Our results show that the affinity between Tpr and RBPs is optimized to maximize the retention of aberrant mRNAs. In addition, we demonstrate how the length of mRNA affects the QC process. Since longer mRNAs spend more time in the nuclear basket to form a compact conformation and initiate their export, nuclear basket proteins could more easily capture and retain them inside the nucleus.

Abnormal Retained Earnings Around The World

OpenAIRE

Alves, Paulo; Silva, Paulo

2017-01-01

Using a firm-level survey database covering 50 countries we evaluate firms´ abnormal retained earnings. The results of our work indicate that firms located in emerging markets retain more earnings than firms from developed countries. On the other hand, firms located on common law based countries retain earnings above the expected and higher than firms placed on civil law based countries. A possible explanation, according to our results, can be seen in the economic growth that these countries ...

Federal Aviation Administration retained savings program proposal

International Nuclear Information System (INIS)

Hostick, D.J.; Larson, L.L.; Hostick, C.J.

1998-03-01

Federal legislation allows federal agencies to retain up to 50% of the savings associated with implementing energy efficiency and water conservation measures and practices. Given budget pressures to reduce expenditures, the use of retained savings to fund additional projects represents a source of funds outside of the traditional budget cycle. The Southwest Region Federal Aviation Administration (FAA) has tasked Pacific Northwest National Laboratory (PNNL) to develop a model retained savings program for Southwest Region FAA use and as a prototype for consideration by the FAA. PNNL recommends the following steps be taken in developing a Southwest Region FAA retained savings program: Establish a retained savings mechanism. Determine the level at which the retained savings should be consolidated into a fund. The preliminary recommendation is to establish a revolving efficiency loan fund at the regional level. Such a mechanism allows some consolidation of savings to fund larger projects, while maintaining a sense of facility ownership in that the funds will remain within the region

Synergistic retention strategy of RGD active targeting and radiofrequency-enhanced permeability for intensified RF & chemotherapy synergistic tumor treatment.

Science.gov (United States)

Zhang, Kun; Li, Pei; He, Yaping; Bo, Xiaowan; Li, Xiaolong; Li, Dandan; Chen, Hangrong; Xu, Huixiong

2016-08-01

Despite gaining increasing attention, chelation of multiple active targeting ligands greatly increase the formation probability of protein corona, disabling active targeting. To overcome it, a synergistic retention strategy of RGD-mediated active targeting and radiofrequency (RF) electromagnetic field-enhanced permeability has been proposed here. It is validated that such a special synergistic retention strategy can promote more poly lactic-co-glycolic acid (PLGA)-based capsules encapsulating camptothecin (CPT) and solid DL-menthol (DLM) to enter and retain in tumor in vitro and in vivo upon exposure to RF irradiation, receiving an above 8 fold enhancement in HeLa retention. Moreover, the PLGA-based capsules can respond RF field to trigger the entrapped DLM to generate solid-liquid-gas (SLG) tri-phase transformation for enhancing RF ablation and CPT release. Therefore, depending on the enhanced RF ablation and released CPT and the validated synergistic retention effect, the inhibitory outcome for tumor growth has gained an over 10-fold improvement, realizing RF ablation & chemotherapy synergistic treatment against HeLa solid tumor, which indicates a significant promise in clinical RF ablation. Copyright © 2016 Elsevier Ltd. All rights reserved.

The short- and long-term fates of memory items retained outside the focus of attention.

Science.gov (United States)

LaRocque, Joshua J; Eichenbaum, Adam S; Starrett, Michael J; Rose, Nathan S; Emrich, Stephen M; Postle, Bradley R

2015-04-01

When a test of working memory (WM) requires the retention of multiple items, a subset of them can be prioritized. Recent studies have shown that, although prioritized (i.e., attended) items are associated with active neural representations, unprioritized (i.e., unattended) memory items can be retained in WM despite the absence of such active representations, and with no decrement in their recognition if they are cued later in the trial. These findings raise two intriguing questions about the nature of the short-term retention of information outside the focus of attention. First, when the focus of attention shifts from items in WM, is there a loss of fidelity for those unattended memory items? Second, could the retention of unattended memory items be accomplished by long-term memory mechanisms? We addressed the first question by comparing the precision of recall of attended versus unattended memory items, and found a significant decrease in precision for unattended memory items, reflecting a degradation in the quality of those representations. We addressed the second question by asking subjects to perform a WM task, followed by a surprise memory test for the items that they had seen in the WM task. Long-term memory for unattended memory items from the WM task was not better than memory for items that had remained selected by the focus of attention in the WM task. These results show that unattended WM representations are degraded in quality and are not preferentially represented in long-term memory, as compared to attended memory items.

17 CFR 256.215 - Appropriated retained earnings.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Appropriated retained earnings... UTILITY HOLDING COMPANY ACT OF 1935 Liabilities and Other Credit Accounts § 256.215 Appropriated retained earnings. This account shall include the amount of retained earnings which has been appropriated or set...

Recruiting and retaining high-quality teachers in rural areas.

Science.gov (United States)

Monk, David H

2007-01-01

In examining recruitment and retention of teachers in rural areas, David Monk begins by noting the numerous possible characteristics of rural communities--small size, sparse settlement, distance from population concentrations, and an economic reliance on agricultural industries that are increasingly using seasonal and immigrant workers to minimize labor costs. Many, though not all, rural areas, he says, are seriously impoverished. Classes in rural schools are relatively small, and teachers tend to report satisfaction with their work environments and relatively few problems with discipline. But teacher turnover is often high, and hiring can be difficult. Monk observes that rural schools have a below-average share of highly trained teachers. Compensation in rural schools tends to be low, perhaps because of a lower fiscal capacity in rural areas, thus complicating efforts to attract and retain teachers. Several student characteristics, including relatively large shares of students with special needs and with limited English skills and lower shares of students attending college, can also make it difficult to recruit and retain high-quality teachers. Other challenges include meeting the needs of highly mobile children of low-income migrant farm workers. With respect to public policy, Monk asserts a need to focus on a subcategory of what might be called hard-to-staff rural schools rather than to develop a blanket set of policies for all rural schools. In particular, he recommends a focus on such indicators as low teacher qualifications, teaching in fields far removed from the area of training, difficulty in hiring, high turnover, a lack of diversity among teachers in the school, and the presence of migrant farm workers' children. Successful efforts to stimulate economic growth in these areas would be highly beneficial. He also calls attention to the potential for modern telecommunication and computing technologies to offset some of the drawbacks associated with teaching

Recruiting and retaining youth and young adults: challenges and opportunities in survey research for tobacco control.

Science.gov (United States)

Cantrell, Jennifer; Hair, Elizabeth C; Smith, Alexandria; Bennett, Morgane; Rath, Jessica Miller; Thomas, Randall K; Fahimi, Mansour; Dennis, J Michael; Vallone, Donna

2018-03-01

Evaluation studies of population-based tobacco control interventions often rely on large-scale survey data from numerous respondents across many geographic areas to provide evidence of their effectiveness. Significant challenges for survey research have emerged with the evolving communications landscape, particularly for surveying hard-to-reach populations such as youth and young adults. This study combines the comprehensive coverage of an address-based sampling (ABS) frame with the timeliness of online data collection to develop a nationally representative longitudinal cohort of young people aged 15-21. We constructed an ABS frame, partially supplemented with auxiliary data, to recruit this hard-to-reach sample. Branded and tested mail-based recruitment materials were designed to bring respondents online for screening, consent and surveying. Once enrolled, respondents completed online surveys every 6 months via computer, tablet or smartphone. Numerous strategies were utilized to enhance retention and representativeness RESULTS: Results detail sample performance, representativeness and retention rates as well as device utilization trends for survey completion among youth and young adult respondents. Panel development efforts resulted in a large, nationally representative sample with high retention rates. This study is among the first to employ this hybrid ABS-to-online methodology to recruit and retain youth and young adults in a probability-based online cohort panel. The approach is particularly valuable for conducting research among younger populations as it capitalizes on their increasing access to and comfort with digital communication. We discuss challenges and opportunities of panel recruitment and retention methods in an effort to provide valuable information for tobacco control researchers seeking to obtain representative, population-based samples of youth and young adults in the U.S. as well as across the globe. © Article author(s) (or their employer

Fine particle retention within stream storage areas at base flow and in response to a storm event

Science.gov (United States)

Drummond, J. D.; Larsen, L. G.; González-Pinzón, R.; Packman, A. I.; Harvey, Judson

2017-01-01

Fine particles (1–100 µm), including particulate organic carbon (POC) and fine sediment, influence stream ecological functioning because they may contain or have a high affinity to sorb nitrogen and phosphorus. These particles are immobilized within stream storage areas, especially hyporheic sediments and benthic biofilms. However, fine particles are also known to remobilize under all flow conditions. This combination of downstream transport and transient retention, influenced by stream geomorphology, controls the distribution of residence times over which fine particles influence stream ecosystems. The main objective of this study was to quantify immobilization and remobilization rates of fine particles in a third-order sand-and-gravel bed stream (Difficult Run, Virginia, USA) within different geomorphic units of the stream (i.e., pool, lateral cavity, and thalweg). During our field injection experiment, a thunderstorm-driven spate allowed us to observe fine particle dynamics during both base flow and in response to increased flow. Solute and fine particles were measured within stream surface waters, pore waters, sediment cores, and biofilms on cobbles. Measurements were taken at four different subsurface locations with varying geomorphology and at multiple depths. Approximately 68% of injected fine particles were retained during base flow until the onset of the spate. Retention was evident even after the spate, with 15.4% of the fine particles deposited during base flow still retained within benthic biofilms on cobbles and 14.9% within hyporheic sediment after the spate. Thus, through the combination of short-term remobilization and long-term retention, fine particles can serve as sources of carbon and nutrients to downstream ecosystems over a range of time scales.

Fine particle retention within stream storage areas at base flow and in response to a storm event

Science.gov (United States)

Drummond, J. D.; Larsen, L. G.; González-Pinzón, R.; Packman, A. I.; Harvey, J. W.

2017-07-01

Fine particles (1-100 µm), including particulate organic carbon (POC) and fine sediment, influence stream ecological functioning because they may contain or have a high affinity to sorb nitrogen and phosphorus. These particles are immobilized within stream storage areas, especially hyporheic sediments and benthic biofilms. However, fine particles are also known to remobilize under all flow conditions. This combination of downstream transport and transient retention, influenced by stream geomorphology, controls the distribution of residence times over which fine particles influence stream ecosystems. The main objective of this study was to quantify immobilization and remobilization rates of fine particles in a third-order sand-and-gravel bed stream (Difficult Run, Virginia, USA) within different geomorphic units of the stream (i.e., pool, lateral cavity, and thalweg). During our field injection experiment, a thunderstorm-driven spate allowed us to observe fine particle dynamics during both base flow and in response to increased flow. Solute and fine particles were measured within stream surface waters, pore waters, sediment cores, and biofilms on cobbles. Measurements were taken at four different subsurface locations with varying geomorphology and at multiple depths. Approximately 68% of injected fine particles were retained during base flow until the onset of the spate. Retention was evident even after the spate, with 15.4% of the fine particles deposited during base flow still retained within benthic biofilms on cobbles and 14.9% within hyporheic sediment after the spate. Thus, through the combination of short-term remobilization and long-term retention, fine particles can serve as sources of carbon and nutrients to downstream ecosystems over a range of time scales.

Surface retention and photochemical reactivity of the diphenylether herbicide oxyfluorfen.

Science.gov (United States)

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.

Interception and retention of simulated cooling tower drift by vegetation

International Nuclear Information System (INIS)

Taylor, F.G. Jr.; Parr, P.D.

1978-01-01

A key issue concerning environmental impacts from cooling tower operation is the interception of drift by vegetation and the efficiency of plants in retaining the residue scavenged from the atmosphere. Chromated drift water, typical of the cooling towers of the Department of Energy's uranium enrichment facilities at Oak Ridge, Tennessee, was prepared using radio-labelled chromium. A portable aerosol generator was used to produce a spectrum of droplets with diameters (100 to 1300 μ) characteristic of cooling towers using state-of-the-art drift eliminators. Efficiency of interception by foliage varied according to leaf morphology with yellow poplar seedlings intercepting 72% of the deposition mass in contrast to 45% by loblolly pine and 24% by fescue grass. Retention patterns of intercepted deposition consisted of a short-time component (0 to 3 days) and a long-time component (3 to 63 days). Retention times, estimated from the regression equation of the long component, indicated that drift contamination from any deposition event may persist from between 8 and 12 weeks. In field situations adjacent to cooling towers, the average annual concentration of drift on vegetation at any distance remains relatively constant, with losses from weathering being compensated by chronic deposition

Influence of humic fractions on retention of isoproturon residues in two Moroccan soils.

Science.gov (United States)

Elkhattabi, Kaouakeb; Bouhaouss, Ahmed; Scrano, Laura; Lelario, Filomena; Bufo, Sabino A

2007-01-01

The influence of different fractions of soil organic matter on the retention of the herbicide isoproturon (IPU) has been evaluated. Water and methanol extractable residues of (14)C labeled isoproturon have been determined in two Moroccan soils by beta -counting-liquid chromatography. The quantification of bound residues in soil and in different fractions of soil humic substances has been performed using pyrolysis/scintillation-detected gas-chromatography. Microbial mineralization of the herbicide and soil organic matter has been also monitored. Retention of isoproturon residues after 30-days incubation ranged from 22% to 32% (non-extractable fraction). The radioactivity extracted in an aqueous environment was from 20% to 33% of the amount used for the treatment; meanwhile, methanol was able to extract another 48%. Both soils showed quantities of bound residues into the humin fraction higher than humic and fulvic acids. The total amount of residues retained into the organic matter of the soils was about 65 % of non-extractable fraction, and this percentage did not change with incubation time; on the contrary, the sorption rate of the retention reaction is mostly influenced by the clay fraction and organic content of the soil. Only a little part of the herbicide was mineralized during the experimental time.

College nursing faculty job satisfaction and retention: A national perspective.

Science.gov (United States)

Lee, Peggy; Miller, Michael T; Kippenbrock, Thomas A; Rosen, Chris; Emory, Jan

The need for registered nurses in the United States continues to grow. To meet this need for increased numbers of nurses, recruitment and retention of qualified nurse educators has become a priority. In addition, the factors associated with nursing faculties' intent to stay have emerged as important considerations for administrators. The concepts of job satisfaction and intent to stay become vital to recruiting and retaining nursing faculty. In the past decade few empirical studies have been conducted on a national scale to address job satisfaction and intent to stay in academia. The purpose of this retrospective study is to analyze variables of relationships with nurse faculty job satisfaction and intent to stay from data collected throughout the United States. The Collaborative on Academic Careers in Higher Education (COACHE) survey was employed for the purposes of this study. Over 1350 nurse educators were included in the survey. The findings support a variety of modifiable variables that are viewed as important by nursing faculty. The strongest relationship was found to be institutional leadership. The implications can inform academic administrators seeking to retain nursing faculty. Copyright © 2017 Elsevier Inc. All rights reserved.

Hydrogen retention properties of polycrystalline tungsten and helium irradiated tungsten

International Nuclear Information System (INIS)

Hino, T.; Koyama, K.; Yamauchi, Y.; Hirohata, Y.

1998-01-01

The hydrogen retention properties of a polycrystalline tungsten and tungsten irradiated by helium ions with an energy of 5 keV were examined by using an ECR ion irradiation apparatus and a technique of thermal desorption spectroscopy, TDS. The polycrystalline tungsten was irradiated at RT with energetic hydrogen ions, with a flux of 10 15 H cm -2 and an energy of 1.7 keV up to a fluence of 5 x 10 18 H cm -2 . Subsequently, the amount of retained hydrogen was measured by TDS. The heating temperature was increased from RT to 1000 C, and the heating rate was 50 C min -1 . Below 1000 C, two distinct hydrogen desorption peaks were observed at 200 C and 400 C. The retained amount of hydrogen was observed to be five times smaller than that of graphite, but the concentration in the implantation layer was comparable with that of graphite. Also, the polycrystalline tungsten was irradiated with 5 keV helium ions up to a fluence of 1.4 x 10 18 He cm -2 , and then re-irradiated with 1.7 keV hydrogen ions. The amount of retained hydrogen in this later experiment was close to the value in the case without prior helium ion irradiation. However, the amount of hydrogen which desorbed around the low temperature peak, 200 C, was largely enhanced. The desorption amount at 200 C saturated for the helium fluence of more than 5 x 10 17 He cm -2 . The present data shows that the trapping state of hydrogen is largely changed by the helium ion irradiation. Additionally, 5 keV helium ion irradiation was conducted on a sample pre-implanted with hydrogen ions to simulate a helium ion impact desorption of hydrogen retained in tungsten. The amount of the hydrogen was reduced as much as 50%. (orig.)

Relationship Between Timing of Multiple Retention Bonuses and the Quality of Officers Retained on the Cost Savings for the Navy

Science.gov (United States)

2016-12-01

psychologically anchor an item’s value at a high price before lowering it until one bidder accepts, earning its name from the way cut flowers are sold...Using the standard bonus system compared to the uniform price auction, the Quality Adjusted Discount (QUAD) auction, and Combinatorial Retention...NUMBER OF PAGES 85 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT Unclassified 18. SECURITY CLASSIFICATION OF THIS PAGE Unclassified 19

Biological significance of dead biomass retention trait in Mediterranean Basin species: an analysis between different successional niches and regeneration strategies as functional groups.

Science.gov (United States)

Baeza, M J; Santana, V M

2015-11-01

Standing dead biomass retention is considered one of the most relevant fuel structural traits to affect plant flammability. However, very little is known about the biological significance of this trait and its distribution between different functional groups. Our aim was to analyse how the proportion of dead biomass produced in Mediterranean species is related to the successional niche of species (early-, mid- and late-successional stages) and the regeneration strategy of species (seeders and resprouters). We evaluated biomass distribution by size classes and standing dead biomass retention in nine dominant species from the Mediterranean Basin in different development stages (5, 9, 14 and 26 years since the last fire). The results revealed significant differences in the standing dead biomass retention of species that presented a distinct successional niche or regeneration strategy. These differences were restricted to the oldest ages studied (>9 years). Tree and small tree resprouters, typical in late-successional stages, presented slight variations with age and a less marked trend to retain dead biomass, while seeder shrubs and dwarf shrubs, characteristic of early-successional stages, showed high dead biomass loads. Our results suggest that the species that tend to retain more dead branches are colonising species that may promote fire in early-successional stages. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

Quantitative assessment of radionuclide retention in the near-surface system at Forsmark. Development of a reactive transport model using Forsmark 1.2 data

Energy Technology Data Exchange (ETDEWEB)

Grandia, Fidel; Sena, Clara; Arcos, David; Molinero, Jorge; Duro, Lara; Bruno, Jordi (Amphos XXI Consulting S.L., Barcelona (Spain))

2007-12-15

been selected for quantitative modelling based on the availability of data and parameters. Two distinct geological and hydrogeological domains have been considered: (1) the till system and (2) the clay system. The first case simulates the intrusion of a radionuclide-bearing fluid from granite bedrock into a relatively dynamic till aquifer. In the second case, the radionuclide bearing fluid interacts with a low permeability, reducing clay layer that is present at the bottom of a discharge zone (such as a lake or the Baltic Sea, for instance), overlying the till deposit. Groundwater flow and transport modelling results highlight the different behaviour of the two simulated systems. The till system constitutes a dynamic aquifer, which reaches the transport steady-state in less than 8 years. On the other hand, the clay system constitutes a relatively low permeability aquitard in which the transport steady state needs hundreds of years to be reached. Reactive transport results indicate that caesium is very strongly retained in the FES of illite in both till and clay systems. Most of the caesium mass entering the system from the deep source is effectively retained in the very close vicinity of the source, independently of the hydrogeological conditions. In the case of uranium, the most effective processes for retention are very different depending on the two considered hydrogeological systems. In the till aquifer, the dissolved uranium is mainly adsorbed onto the charged surfaces of ferrihydrite. It is seen that this dynamic aquifer system still exhibits a uranium retention efficiency of about 50% even after about 100 years of simulation time. On the other hand, the simulated clay system is much more efficient than the till aquifer for uranium retention due to the precipitation of amorphous uranium (IV) oxides. Uranium retention efficiencies higher than 95% are computed for the clay system, even after more than 400 years. As in the case of caesium, most of the uranium mass

Postpartum MR diagnosis of retained placenta accreta

International Nuclear Information System (INIS)

Tanaka, Yumiko Oishi; Itai, Yuji; Shigemitsu, Sadahiko; Ichikawa, Yoshihito; Sohda, Satoshi; Yoshikawa, Hiroyuki

2004-01-01

Retained placenta accreta can cause catastrophic postpartum hemorrhage. This study aims to determine whether MR imaging can differentiate retained placenta accreta from postpartum hemorrhage caused by other conditions. Fourteen cases suspicious for retained placenta were examined with MR imaging. Signal intensity, the enhancing pattern of uterine contents, and flow voids within the myometrium were retrospectively studied. As hysterectomy was performed in only two cases, final diagnosis was based on clinical outcome and analysis of uterine contents. Final diagnoses were retained placenta accreta in seven cases, retained normally attached placenta in four, hematoma in two, and placental site trophoblastic tumor (PSTT) in one. All seven cases with placenta accreta had a very hyperintense area on T2-weighted images, showing transient early enhancement. None demonstrated delayed strong enhancement around the hyperintense area. In two cases with retained normally attached placenta and in both with hematomas, there were no hyperintense areas on T2-weighted images. Of these, only one showed transient early enhancement. Flow voids were observed in four cases with placenta accreta, one with normally attached placenta, and the case with PSTT. A markedly hyperintense area on T2-weighted images and transient early enhancement without delayed strong enhancement between the mass and the myometrium can indicate retained placenta accreta. (orig.)

Postpartum MR diagnosis of retained placenta accreta

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Yumiko Oishi; Itai, Yuji [Department of Radiology, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennodai, 305-8575, Tsukuba, Ibaraki (Japan); Shigemitsu, Sadahiko [Department of Obstetrics and Gynecology, Ryugasaki Saiseikai General Hospital, Ryagasaki (Japan); Ichikawa, Yoshihito; Sohda, Satoshi; Yoshikawa, Hiroyuki [Department of Obstetrics and Gynecology, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennodai, 305-8575, Tsukuba, Ibaraki (Japan)

2004-06-01

Retained placenta accreta can cause catastrophic postpartum hemorrhage. This study aims to determine whether MR imaging can differentiate retained placenta accreta from postpartum hemorrhage caused by other conditions. Fourteen cases suspicious for retained placenta were examined with MR imaging. Signal intensity, the enhancing pattern of uterine contents, and flow voids within the myometrium were retrospectively studied. As hysterectomy was performed in only two cases, final diagnosis was based on clinical outcome and analysis of uterine contents. Final diagnoses were retained placenta accreta in seven cases, retained normally attached placenta in four, hematoma in two, and placental site trophoblastic tumor (PSTT) in one. All seven cases with placenta accreta had a very hyperintense area on T2-weighted images, showing transient early enhancement. None demonstrated delayed strong enhancement around the hyperintense area. In two cases with retained normally attached placenta and in both with hematomas, there were no hyperintense areas on T2-weighted images. Of these, only one showed transient early enhancement. Flow voids were observed in four cases with placenta accreta, one with normally attached placenta, and the case with PSTT. A markedly hyperintense area on T2-weighted images and transient early enhancement without delayed strong enhancement between the mass and the myometrium can indicate retained placenta accreta. (orig.)

How does dialectical behavior therapy facilitate treatment retention among individuals with comorbid borderline personality disorder and substance use disorders?

Science.gov (United States)

Bornovalova, Marina A; Daughters, Stacey B

2007-12-01

For individuals presenting with comorbid borderline personality disorder (BPD) and substance use disorders (SUD), rates of treatment dropout from combined mental health and substance abuse treatment centers approach 80%, rendering dropout the rule rather than the exception. Several studies indicate that utilizing a more comprehensive treatment such as Dialectical Behavior Therapy (DBT) may be useful for client retention; however, given the scope and effort required to conduct this treatment, it may be more practical to determine which specific components within DBT are useful in retaining clients in substance use treatment. Thus, the purpose of the current paper is first to determine what exact deficits underlie treatment dropout among the BPD-SUD comorbidity. Second, we review and evaluate effectiveness of DBT retention-enhancing strategies by assembling work from other samples and literatures that also tests retention-enhancing strategies discussed in DBT. As a last step, the paper will conclude with a discussion on methodological limitations and potential future directions in this line of research.

An Innovative Method for Estimating Soil Retention at a ...

Science.gov (United States)

Planning for a sustainable future should include an accounting of services currently provided by ecosystems such as erosion control. Retention of soil improves fertility, increases water retention, and decreases sedimentation in streams and rivers. Landscapes patterns that facilitate these services could help reduce costs for flood control, dredging of reservoirs and waterways, while maintaining habitat for fish and other species important to recreational and tourism industries. Landscape scale geospatial data available for the continental United States was leveraged to estimate sediment erosion (RUSLE-based, Renard, et al. 1997) employing recent geospatial techniques of sediment delivery ratio (SDR) estimation (Cavalli, et al. 2013). The approach was designed to derive a quantitative approximation of the ecological services provided by vegetative cover, management practices, and other surface features with respect to protecting soils from the erosion processes of detachment, transport, and deposition. Quantities of soil retained on the landscape and potential erosion for multiple land cover scenarios relative to current (NLCD 2011) conditions were calculated for each calendar month, and summed to yield annual estimations at a 30-meter grid cell. Continental-scale data used included MODIS NDVI data (2000-2014) to estimate monthly USLE C-factors, gridded soil survey geographic (gSSURGO) soils data (annual USLE K factor), PRISM rainfall data (monthly USLE

Retention of Adult Patients on Antiretroviral Therapy in Low- and Middle-Income Countries: Systematic Review and Meta-analysis 2008-2013.

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Fox, Matthew P; Rosen, Sydney

2015-05-01

We previously published systematic reviews of retention in care after antiretroviral therapy initiation among general adult populations in sub-Saharan Africa. We estimated 36-month retention at 73% for publications from 2007 to 2010. This report extends the review to cover 2008-2013 and expands it to all low- and middle-income countries. We searched PubMed, Embase, Cochrane Register, and ISI Web of Science from January 1, 2008, to December 31, 2013, and abstracts from AIDS and IAS from 2008-2013. We estimated retention across cohorts using simple averages and interpolated missing times through the last time reported. We estimated all-cause attrition (death, loss to follow-up) for patients receiving first-line antiretroviral therapy in routine settings in low- and middle-income countries. We found 123 articles and abstracts reporting retention for 154 patient cohorts and 1,554,773 patients in 42 countries. Overall, 43% of all patients not retained were known to have died. Unweighted averages of reported retention were 78%, 71%, and 69% at 12, 24, and 36 months, after treatment initiation, respectively. We estimated 36-month retention at 65% in Africa, 80% in Asia, and 64% in Latin America and the Caribbean. From lifetable analysis, we estimated retention at 12, 24, 36, 48, and 60 months at 83%, 74%, 68%, 64%, and 60%, respectively. Retention at 36 months on treatment averages 65%-70%. There are several important gaps in the evidence base, which could be filled by further research, especially in terms of geographic coverage and duration of follow-up.

Inhalation deposition and retention patterns of a U-Pu chain aggregate aerosol

International Nuclear Information System (INIS)

Briant, J.K.; Sanders, C.L.

1987-01-01

Chain aggregate aerosol particles are normally formed during many high-temperature combustion and vaporization processes. The shape of chain aggregate aerosol particles could have an effect on the pattern of inhalation deposition and retention of the particles in the respiratory tract. A chain aggregate aerosol of nuclear reactor fuel could be present as an inhalation hazard if it were released to the atmosphere after a meltdown, core-disruptive accident. Rats were exposed to a chain aggregate U-Pu aerosol made by laser vaporization of mixed-oxide, breeder reactor fuel (20% plutonium dioxide and 80% uranium dioxide), then sacrificed to measure the clearance and retention of the fuel aerosol particles. Deposition of the 0.7-micron (activity median aerodynamic equivalent diameter) aerosol particles resulted in an average initial lung burden of 4140 Bq alpha activity. The chain aggregate particle shape was not a major factor in the total deposition; however, it may have influenced the regional distribution of the activity deposited. Retention of the particles in the upper airways of the tracheobronchial tree was on the order of 1% of the concurrent lung burden, which is consistent with recent data of other investigations. This study indicates that insoluble chain aggregate particles are retained in the tracheobronchial airways to a degree similar to simple spherically shaped particles of equivalent volume diameter

Positive organisation: The role of leader behaviour in work engagement and retention

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Fallen Mendes

2011-05-01

Research purpose: The aim of this study was to investigate if leader empowering behaviour can positively impact on role clarity, psychological empowerment and work engagement, with the final outcome being the retention of talent. Motivation for the study: In the ever changing work environment organisations place great emphasis on their human capital. The positive organisation utilises specific elements to optimise human capital’s potential. It is therefore important to identify the elements contributing to a positive organisation as well as the elements which lead to the retention of talent. Research design, approach and method: A survey research design was used. A convenience sample (n = 179 was taken from a business unit in a chemical organisation. The Leader Empowering Behaviour Questionnaire, Measures of Role Clarity and Ambiguity Questionnaire, Measuring Empowerment Questionnaire, Utrecht Work Engagement Scale and the Intention to Leave Scale were administered. Main findings: Leader empowering behaviour, role clarity and psychological empowerment predicted work engagement. Role clarity interacted with competence to affect employees’ dedication and interacted with the development of employees to affect absorption. Work engagement predicted employees’ intention to leave. Practical/managerial implications: Organisations should foster the elements of a positive organisation if they want to retain their talent. Contribution/value-add: The results of this research contribute to scientific knowledge about the effects of a positive organisation on retention.

Exploring the Effects of Hope on GPA and Retention among College Undergraduate Students on Academic Probation

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Holly Seirup

2011-01-01

Full Text Available This study analyzed the impact of hope on the academic achievement and retention of 235 students on academic probation at a private Northeastern university. Probationary students were enrolled in a mandatory online course designed to facilitate academic and nonacademic skills, to improve student GPAs and overall retention. The Hope Scale (Snyder et al. (1991 was administered to identify whether students with greater levels of hope would experience an increase in academic success upon completion of the course. Students were broken down into groups of high, medium, and low hope based on their scores on the instrument. Results showed students who completed the course were more likely to be retained than those who did not complete the course, had a slight increase in GPA by the end of the semester, and high-hope students showed the greatest overall gain in GPAs.

Implanted Deuterium Retention and Release in Carbon-Coated Beryllium

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Anderl, R. A.; Longhurst, G. R.; Pawelko, R. J.; Oates, M. A.

1997-06-01

Deuterium implantation experiments have been conducted on samples of clean and carbon-coated beryllium. These studies entailed preparation and characterization of beryllium samples coated with carbon thicknesses of 100, 500, and 1000 Å. Heat treatment of a beryllium sample coated with carbon to a thickness of approximately 100 Å revealed that exposure to a temperature of 400°C under high vacuum conditions was sufficient to cause substantial diffusion of beryllium through the carbon layer, resulting in more beryllium than carbon at the surface. Comparable concentrations of carbon and beryllium were observed in the bulk of the coating layer. Higher than expected oxygen levels were observed throughout the coating layer as well. Samples were exposed to deuterium implantation followed by thermal desorption without exposure to air. Differences were observed in deuterium retention and postimplantation release behavior in the carbon-coated samples as compared with bare samples. For comparable implantation conditions (sample temperature of 400°C and an incident deuterium flux of approximately 6 × 1019 D/m2-s), the quantity of deuterium retained in the bare sample was less than that retained in the carbon-coated samples. Further, the release of the deuterium took place at lower temperatures for the bare beryllium surfaces than for carbon-coated beryllium samples.

Individual and community factors associated with geographic clusters of poor HIV care retention and poor viral suppression.

Science.gov (United States)

Eberhart, Michael G; Yehia, Baligh R; Hillier, Amy; Voytek, Chelsea D; Fiore, Danielle J; Blank, Michael; Frank, Ian; Metzger, David S; Brady, Kathleen A

2015-05-01

Previous analyses identified specific geographic areas in Philadelphia (hotspots) associated with negative outcomes along the HIV care continuum. We examined individual and community factors associated with residing in these hotspots. Retrospective cohort of 1404 persons newly diagnosed with HIV in 2008-2009 followed for 24 months after linkage to care. Multivariable regression examined associations between individual (age, sex, race/ethnicity, HIV transmission risk, and insurance status) and community (economic deprivation, distance to care, access to public transit, and access to pharmacy services) factors and the outcomes: residence in a hotspot associated with poor retention-in-care and residence in a hotspot associated with poor viral suppression. In total, 24.4% and 13.7% of persons resided in hotspots associated with poor retention and poor viral suppression, respectively. For persons residing in poor retention hotspots, 28.3% were retained in care compared with 40.4% of those residing outside hotspots (P care, and longer distance to pharmacies. Factors significantly associated with residence in poor viral suppression hotspots included female sex, higher economic deprivation, and shorter distance to pharmacies. Individual and community-level associations with geographic hotspots may inform both content and delivery strategies for interventions designed to improve retention-in-care and viral suppression.

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

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Muriel T N Panouillères

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

Flavor Dependent Retention of Remote Food Preference Memory.

Science.gov (United States)

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

2017-01-01

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

Analysis of Different Positions of Fiber-Reinforced Composite Retainers versus Multistrand Wire Retainers Using the Finite Element Method

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Arezoo Jahanbin

2014-01-01

Full Text Available Background. The aim of this study was to evaluate root displacement of the lower incisors fixed with FRC in different positions versus FSW retainers using the finite element method. Materials and Methods. 3D finite element models were designed for a mandibular anterior segment: Model 1: flexible spiral wire bonded to the lingual teeth surfaces, Model 2: FRC bonded to the upper third of lingual teeth surfaces, and Model 3: FRC bonded to the middle third. FE analysis was performed for three models and then tooth displacements were evaluated. Results. In contrast to lateral incisors and canines, the FSW retainer caused the central teeth to move more than the teeth bonded with FRC in both loadings. Comparison between Models 2 and 3 (in vertical loading showed that FRC retainers that bonded at the upper third of lingual teeth surfaces made central and canine teeth move less than FRC retainers bonded at the middle third; however, for lateral teeth it was the opposite. Conclusion. FRC retainers bonded at the upper third of lingual teeth surfaces make central and canine teeth move less than FRC retainers bonded at the middle third in vertical loading; however, for lateral teeth it was the opposite.

A single-server Markovian queuing system with discouraged arrivals and retention of reneged customers

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Kumar Rakesh

2014-01-01

Full Text Available Customer impatience has a very negative impact on the queuing system under investigation. If we talk from business point of view, the firms lose their potential customers due to customer impatience, which affects their business as a whole. If the firms employ certain customer retention strategies, then there are chances that a certain fraction of impatient customers can be retained in the queuing system. A reneged customer may be convinced to stay in the queuing system for his further service with some probability, say q and he may abandon the queue without receiving the service with a probability p(=1− q. A finite waiting space Markovian single-server queuing model with discouraged arrivals, reneging and retention of reneged customers is studied. The steady state solution of the model is derived iteratively. The measures of effectiveness of the queuing model are also obtained. Some important queuing models are derived as special cases of this model.

Retention of laparoscopic psychomotor skills after a structured training program depends on the quality of the training and on the complexity of the task.

Science.gov (United States)

Molinas, Carlos Roger; Campo, Rudi

2016-01-01

This follow-up RCT was conducted to evaluate laparoscopic psychomotor skills retention after finishing a structured training program. In a first study, 80 gynecologists were randomly allocated to four groups to follow different training programs for hand-eye coordination (task 1) with the dominant hand (task 1-a) and the non-dominant hand (task 1-b) and laparoscopic intra-corporeal knot tying (task 2) in the Laparoscopic Skills Testing and Training (LASTT) model. First, baseline skills were tested (T1). Then, participants trained task 1 (G1: 1-a and 1-b, G2: 1-a only, G3 and G4: none) and then task 2 (all groups but G4). After training all groups were tested again to evaluate skills acquisition (T2). For this study, 2 years after a resting period, 73 participants were recruited and tested again to evaluate skills retention (T3). All groups had comparable skills at T1 for all tasks. At T2, G1, G2, and G3 improved their skills, but the level of improvement was different (G1 = G2 > G3 > G4 for task 1; G1 = G2 = G3 > G4 for task 2). At T3, all groups retained their task 1 skills at the same level than at T2. For task 2, however, a skill decay was already noticed for G2 and G3, being G1 the only group that retained their skills at the post-training level. Training improves laparoscopic skills, which can be retained over time depending on the comprehensiveness of the training program and on the complexity of the task. For high complexity tasks, full training is advisable for both skills acquisition and retention.

A retained menstrual cup.

Science.gov (United States)

Day, S

2012-05-01

A 20-year-old woman attended a genitourinary clinic with a retained vaginal Mooncup that she had inserted the night before. A Mooncup is one type of menstrual cup. On speculum examination the device was visualized high in the vagina and the cervix appeared firmly lodged within it. The physician experienced difficulty in retrieving the cup despite following product instructions. This case highlights a new adverse event with an increasingly used sanitation product. It is important that clinicians are familiar with the cup, its removal process and are able to counsel patients with retained devices on future correct placement.

Rainwater runoff retention on an aged intensive green roof.

Science.gov (United States)

Speak, A F; Rothwell, J J; Lindley, S J; Smith, C L

2013-09-01

Urban areas are characterised by large proportions of impervious surfaces which increases rainwater runoff and the potential for surface water flooding. Increased precipitation is predicted under current climate change projections, which will put further pressure on urban populations and infrastructure. Roof greening can be used within flood mitigation schemes to restore the urban hydrological balance of cities. Intensive green roofs, with their deeper substrates and higher plant biomass, are able to retain greater quantities of runoff, and there is a need for more studies on this less common type of green roof which also investigate the effect of factors such as age and vegetation composition. Runoff quantities from an aged intensive green roof in Manchester, UK, were analysed for 69 rainfall events, and compared to those on an adjacent paved roof. Average retention was 65.7% on the green roof and 33.6% on the bare roof. A comprehensive soil classification revealed the substrate, a mineral soil, to be in good general condition and also high in organic matter content which can increase the water holding capacity of soils. Large variation in the retention data made the use of predictive regression models unfeasible. This variation arose from complex interactions between Antecedant Dry Weather Period (ADWP), season, monthly weather trends, and rainfall duration, quantity and peak intensity. However, significantly lower retention was seen for high rainfall events, and in autumn, which had above average rainfall. The study period only covers one unusually wet year, so a longer study may uncover relationships to factors which can be applied to intensive roofs elsewhere. Annual rainfall retention for Manchester city centre could be increased by 2.3% by a 10% increase in intensive green roof construction. The results of this study will be of particular interest to practitioners implementing greenspace adaptation in temperate and cool maritime climates. Copyright © 2013

The influence of additional fluors on the retention ability of dough and the technological quality of bakery products

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Tatiana Bojňanská

2015-08-01

Full Text Available The work monitored rheofermentation properties of dough prepared from composite flours formed by 70% of wheat flour T650 and the addition of 30%. Three kinds of additions were used, namely spelt flour, amaranth flour and buckwheat flour. To determine rheofermentation properties Rheofermentometer Rhea F4 was used, by means of which the dough development, the production of fermentation gases, retention ability of dough and the activity of used baking yeast were analysed. The best ability to retain formed fermentation gas had wheat flour (control and composite flour with the addition of spelt flour. The composite flour with addition of amaranth flour showed a retention coefficient compared to the control lower by 13%, and the composite flour with addition of buckwheat flour showed a retention coefficient compared to the control reduced by 20%. Control flour and composite flours were then processed in the baking experiment. Based on its results it was possible to evaluate the effect of the addition and retention capacity of dough on the quality of the final products (experimental loaves. The biggest loaf volume (200 cm3 and the optimal vaulting (0.65 were found in the control and a loaf made of composite flour with addition of spelt. Loaf volume, produced from composite flours with the addition of amaranth, and buckwheat was compared to control lower by 18.7%, and 16.3% respectively. The value of vaulting of these products (0.40 can be evaluated as unsatisfactory. Based on the evaluation of results observed by measuring on the rheofermentometer and baking experiment results it can be concluded that a better ability to retain the formed fermentation gas, thus ensuring high volume, had loaves made from wheat flour T650 and composite flour with addition of spelt flour. Based on the findings, it is possible to state that the results of rheofermentometric measurements predict the volume and vaulting of bakery products. By means of Rheofermentometer

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

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Dileep Nag Vinnakota

2015-01-01

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

Nitrogen limitation, 15N tracer retention, and growth response in intact and Bromus tectorum-invaded Artemisia tridentata ssp. wyomingensis communities

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Witwicki, Dana L.; Doescher, Paul S.; Pyke, David A.; DeCrappeo, Nicole M.; Perakis, Steven S.

2012-01-01

Annual grass invasion into shrub-dominated ecosystems is associated with changes in nutrient cycling that may alter nitrogen (N) limitation and retention. Carbon (C) applications that reduce plant-available N have been suggested to give native perennial vegetation a competitive advantage over exotic annual grasses, but plant community and N retention responses to C addition remain poorly understood in these ecosystems. The main objectives of this study were to (1) evaluate the degree of N limitation of plant biomass in intact versus B. tectorum-invaded sagebrush communities, (2) determine if plant N limitation patterns are reflected in the strength of tracer 15N retention over two growing seasons, and (3) assess if the strength of plant N limitation predicts the efficacy of carbon additions intended to reduce soil N availability and plant growth. Labile C additions reduced biomass of exotic annual species; however, growth of native A. tridentata shrubs also declined. Exotic annual and native perennial plant communities had divergent responses to added N, with B. tectorum displaying greater ability to use added N to rapidly increase aboveground biomass, and native perennials increasing their tissue N concentration but showing little growth response. Few differences in N pools between the annual and native communities were detected. In contrast to expectations, however, more 15N was retained over two growing seasons in the invaded annual grass than in the native shrub community. Our data suggest that N cycling in converted exotic annual grasslands of the northern Intermountain West, USA, may retain N more strongly than previously thought.

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

Science.gov (United States)

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

2013-12-01

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

Nurse retention in a correctional facility: a study of the relationship between the nurses' perceived barriers and benefits.

Science.gov (United States)

Chafin, W Sue; Biddle, Wendy L

2013-04-01

Retention of nursing staff is more complex in a correctional facility. After a period of 3 years, only 20% of the staff remained employed at this study facility. Without retention of qualified correctional nurses, there are decreases in access to care, gaps in continuity of care, and less time for mentorship. Trained correctional nurses improve patient and staff safety, provide more education, and are more team-oriented. The purpose of this study was to identify barriers and benefits to nursing staff satisfaction with their job and the likelihood that they will continue to work in correctional settings. Practice and patient care will be favorably impacted if correctional nurses are provided with services such as new hire orientation, clinical ladder programs to recruit and retain nursing staff, and teambuilding.

CUSTOMER RETENTION IN FASHION E-TAILING: FACILITATORS AND BARRIERS

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Annika Hallberg

2017-09-01

Full Text Available The Internet has changed the way consumers gather information and shop. An increasingly competitive market calls for new marketing approaches to attract customers to the companies’ online stores. The aim of the present article is to understand what facilitates and what creates barriers to prioritizing repeat customers. Further, the article discusses repurchasing among young female online fashion shoppers and how these consumers can be retained. Two research questions are addressed: 1. What facilitates repurchasing among online fashion consumers, and why? 2. What creates barriers to re-purchasing among online fashion consumers, and why? In order to gain deeper knowledge of how e-tailers work with customer retention, we conducted a pilot study that included representatives from two clothing companies, as well as an expert interview with an analyst at the company Stroede Ralto. Then two focus groups consisting of young female online shoppers were formed. Results from the focus groups show that several companies use frequent e-mail advertising and targeted advertising on other websites to retain customers and facilitate re-purchasing. All participants found these features annoying rather than helpful. Moreover, the help functions provided in an online store played a major role in facilitating the purchasing, and shopping carts were appreciated as they enable customers to easily view and add items and obtain price information. We discovered that the consumers did most of their shopping on websites they found esthetically appealing and inspiring and that they would often return to these websites for inspiration or to browse. The article further provides advice to managers regarding how to retain customers.

Implant-retained overdenture as a standard treatment modality for severely resorbed mandibular ridges

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Angleena Y Daniel

2017-01-01

Full Text Available Edentulous patients are a diverse group comprised those who are anatomically deficient, medically compromised, economically depressed, geriatric as well as the general population that, for a number of other reasons have been rendered edentulous. Satisfying a completely edentulous patient is always considered a difficult task. Various treatment options for rehabilitation of a completely edentulous patient are available: conventional complete dentures, overdentures, implant-supported overdenture, and full arch fixed implant-supported prosthesis. While the conventional denture may meet the needs of many patients, others require more retention, stability, function, and esthetics, especially in the mandible. With the continued advancements in dental implant therapy, it is becoming increasingly easier for the clinician to provide treatment solutions that can effectively meet functional, economic, and social expectations of each individual patient. This paper presents a case report of prosthetic rehabilitation of a completely edentulous patient with implant-retained overdenture.

Vocation, friendship and resilience: a study exploring nursing student and staff views on retention and attrition.

Science.gov (United States)

Williamson, Graham R; Health, Val; Proctor-Childs, Tracey

2013-01-01

There is international concern about retention of student nurses on undergraduate programmes. United Kingdom Higher Education Institutions are monitored on their attrition statistics and can be penalised financially, so they have an incentive to help students remain on their programmes beyond their moral duty to ensure students receive the best possible educational experience. to understand students' and staff concerns about programmes and placements as part of developing our retention strategies. This study reports qualitative data on retention and attrition collected as part of an action research study. One University School of Nursing and Midwifery in the South West of England. Staff, current third year and ex-student nurses from the adult field. Data were collected in focus groups, both face-to face and virtual, and individual telephone interviews. These were transcribed and subjected to qualitative content analysis. FOUR THEMES EMERGED: Academic support, Placements and mentors, Stresses and the reality of nursing life, and Dreams for a better programme. The themes Academic support, Placements and mentors and Stresses and the reality of nursing life, resonate with international literature. Dreams for a better programme included smaller group learning. Vocation, friendship and resilience seem instrumental in retaining students, and Higher Education Institutions should work to facilitate these. 'Vocation' has been overlooked in the retention discussions, and working more actively to foster vocation and belongingness could be important.

Identifying research priorities for effective retention strategies in clinical trials.

Science.gov (United States)

Kearney, Anna; Daykin, Anne; Shaw, Alison R G; Lane, Athene J; Blazeby, Jane M; Clarke, Mike; Williamson, Paula; Gamble, Carrol

2017-08-31

The failure to retain patients or collect primary-outcome data is a common challenge for trials and reduces the statistical power and potentially introduces bias into the analysis. Identifying strategies to minimise missing data was the second highest methodological research priority in a Delphi survey of the Directors of UK Clinical Trial Units (CTUs) and is important to minimise waste in research. Our aim was to assess the current retention practices within the UK and priorities for future research to evaluate the effectiveness of strategies to reduce attrition. Seventy-five chief investigators of NIHR Health Technology Assessment (HTA)-funded trials starting between 2009 and 2012 were surveyed to elicit their awareness about causes of missing data within their trial and recommended practices for improving retention. Forty-seven CTUs registered within the UKCRC network were surveyed separately to identify approaches and strategies being used to mitigate missing data across trials. Responses from the current practice surveys were used to inform a subsequent two-round Delphi survey with registered CTUs. A consensus list of retention research strategies was produced and ranked by priority. Fifty out of seventy-five (67%) chief investigators and 33/47 (70%) registered CTUs completed the current practice surveys. Seventy-eight percent of trialists were aware of retention challenges and implemented strategies at trial design. Patient-initiated withdrawal was the most common cause of missing data. Registered CTUs routinely used newsletters, timeline of participant visits, and telephone reminders to mitigate missing data. Whilst 36 out of 59 strategies presented had been formally or informally evaluated, some frequently used strategies, such as site initiation training, have had no research to inform practice. Thirty-five registered CTUs (74%) participated in the Delphi survey. Research into the effectiveness of site initiation training, frequency of patient contact

Swedish Collective Agreements and Employers’ Willingness to Hire and Retain Older Workers in Employment

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Carin Ulander-Wänman

2016-06-01

Full Text Available Demographic change is transforming the EU population structure for the coming decades. One challenge that society faces is to preserve social welfare when elderly persons comprise a larger proportion of the total population. Allowing people to work beyond the current retirement age may help slow the growth of the maintenance burden for welfare costs, and creating situations where larger numbers of older employees can work longer and complete more working hours can improve conditions for preserving and developing welfare. However, a prolonged working life presupposes several conditions; one of these is that legal regulation of the labor market must support employers’ willingness to hire and retain older workers in employment. This article explores employers’ attitudes toward regulations in Swedish collective agreements—regulations which are of particular importance if employers are to increase hiring and retention of older workers in employment.

Reality of Retainers

Science.gov (United States)

... the cafeteria take out his retainer before eating lunch. Carefully, he places it in a plastic container to make sure that it's safe while he eats. You can tell that this small plastic and metal mouthpiece is important to him. ...

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

International Nuclear Information System (INIS)

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

1984-01-01

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

The use of a neodymium-iron-boron magnet device for positioning a multi-stranded wire retainer in lingual retention--a pilot study in humans.

Science.gov (United States)

Hahn, Wolfram; Fricke, Julia; Fricke-Zech, Susanne; Zapf, Antonia; Gruber, Rudolf; Sadat-Khonsari, Reza

2008-10-01

The aim of this study was to evaluate the time requirement of a newly developed device made of neodymium-iron-boron (NdFeB) magnets for positioning a multi-stranded, canine-to-canine retainer during bonding compared with dental floss and a transfer tray. Forty-five patients aged between 12 and 33 years (26 male, 19 female) previously treated with fixed appliances were enrolled in the study. The patients were randomly allocated to three groups (15 per group). For each group a mandibular canine-to-canine retainer of 0.018 inch Dentaflex multi-stranded wire (Dentaurum) was prefabricated for each patient on a cast. The bonding procedure was identical, except for the method of positioning the wire during adhesive fixation: group A dental floss, group B a small prefabricated transfer tray of dental resin and group C the NdFeB magnet device. For each group, the time required for the complete bonding process was measured. Kruskal-Wallis and Wilcoxon-Mann-Whitney tests were used for group and pairwise comparisons, respectively. The three methods required statistically significant different times (P NdFeB magnet device is a timesaving appliance for positioning a multi-stranded, canine-to-canine retainer during bonding when compared with dental floss and an individually prefabricated transfer tray.

Augmenting retention and stability of an occlusal device for a partially dentate patient using existing extracoronal attachments: a clinical report.

Science.gov (United States)

Al-Rowaieh, Saleh A

2011-04-01

Occlusal devices are a valid treatment modality in certain clinical situations. For an occlusal device to be effective, sufficient retention and stability should be derived from coverage of the occlusal and incisal surfaces of the teeth. In the absence of most or all of the posterior teeth, the effectiveness of the device could become compromised as the incisal portions of the anterior teeth are typically not conducive to adequately retaining and stabilizing the device. This clinical report describes an approach to improving the retention and stability of an occlusal device for a patient with shortened dental arches by use of the patient's existing extracoronal attachments. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Carbon dynamics and retention in soil after anaerobic digestion of dairy cattle feed and faeces

DEFF Research Database (Denmark)

Thomsen, Ingrid Kaag; Olesen, Jørgen E; Møller, Henrik Bjarne

2013-01-01

Animal manure and plant biomass are increasingly used for methane production. While minerals may be conserved during gas generation, the composition of the biogenic material is changed and less carbon (C) is returned to the soil in the digested residue. We evaluated the fate of C in ruminant feed...... model (pool half-lives: 4, 20 and 100 days). During anaerobic digestion, gaseous C losses were 80 and 46% of the C in feed and faeces, respectively. The model predicted that 14, 58, 48, and 76% of the C applied in feed, digested feed, faeces and digested faeces are retained in soil after 1 to 2 years....... When C lost during the pre-treatments was included, the long-term C retention in soil accounted for 12–14% of the C initially present in the feed. We conclude that soil microbial activity is reduced when residues are anaerobically digested for biogas before being applied to soil. However, the retention...

76 FR 69126 - Graduated Retained Interests

Science.gov (United States)

2011-11-08

... in trust or otherwise) includible in the grantor's gross estate if the grantor has retained the use..., or for a period that does not in fact end before the grantor's death. The final regulations will... trust corpus of a grantor retained annuity or unitrust trust (GRT) that is includible in the grantor's...

Recruiting and retaining child welfare workers: is preparing social work students enough for sustained commitment to the field?

Science.gov (United States)

Barbee, Anita P; Antle, Becky; Sullivan, Dana J; Huebner, Ruth; Fox, Steve; Hall, Jon Christopher

2009-01-01

Graduates of specialized BSW child welfare education programs are more likely to be retained after two years of service in the agency, but many leave at the four year mark. Two studies explored possible reasons for departure at this time. The first study found that graduates of specialized child welfare programs were significantly more likely to engage in best practices in nine areas than workers from other fields. Thus, frustration with practice skill was ruled out as a cause. The second qualitative study found that poor supervision, lack of coworker support, and organizational stress among other variables prompted these high-functioning workers to leave the agency. Suggestions for innovative interventions to enhance retention at this critical juncture are included.

Stepped-Wedge Cluster Randomized Controlled Trial to Promote Option B+ Retention in Central Mozambique.

Science.gov (United States)

Pfeiffer, James T; Napúa, Manuel; Wagenaar, Bradley H; Chale, Falume; Hoek, Roxanne; Micek, Mark; Manuel, João; Michel, Cathy; Cowan, Jessica Greenberg; Cowan, James F; Gimbel, Sarah; Sherr, Kenneth; Gloyd, Stephen; Chapman, Rachel R

2017-11-01

This randomized trial studied performance of Option B+ in Mozambique and evaluated an enhanced retention package in public clinics. The study was conducted at 6 clinics in Manica and Sofala Provinces in central Mozambique. Seven hundred sixty-one pregnant women tested HIV+, immediately initiated antiretroviral (ARV) therapy, and were followed to track retention at 6 clinics from May 2014 to May 2015. Clinics were randomly allocated within a stepped-wedge fashion to intervention and control periods. The intervention included (1) workflow modifications and (2) active patient tracking. Retention was defined as percentage of patients returning for 30-, 60-, and 90-day medication refills within 25-35 days of previous refills. During control periods, 52.3% of women returned for 30-day refills vs. 70.8% in intervention periods [odds ratio (OR): 1.80; 95% confidence interval (CI): 1.05 to 3.08]. At 60 days, 46.1% control vs. 57.9% intervention were retained (OR: 1.82; CI: 1.06 to 3.11), and at 90 days, 38.3% control vs. 41.0% intervention (OR: 1.04; CI: 0.60 to 1.82). In prespecified subanalyses, birth before pickups was strongly associated with failure-women giving birth before ARV pickup were 33.3 times (CI: 4.4 to 250.3), 7.5 times (CI: 3.6 to 15.9), and 3.7 times (CI: 2.2 to 6.0) as likely to not return for ARV pickups at 30, 60, and 90 days, respectively. The intervention was effective at 30 and 60 days, but not at 90 days. Combined 90-day retention (40%) and adherence (22.5%) were low. Efforts to improve retention are particularly important for women giving birth before ARV refills.

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

Science.gov (United States)

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

2015-11-01

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

Factors That Influence Enrolment and Retention in Ghana’ National Health Insurance Scheme

Science.gov (United States)

Millicent Kotoh, Agnes; Aryeetey, Genevieve Cecilia; der Geest, Sjaak Van

2018-01-01

Background: The government of Ghana introduced the National Health Insurance Scheme (NHIS) in 2004 with the goal of achieving universal coverage within 5 years. Evidence, however, shows that expanding NHIS coverage and especially retaining members have remained a challenge. A multilevel perspective was employed as a conceptual framework and methodological tool to examine why enrolment and retention in the NHIS remains low. Methods: A household survey was conducted after 20 months educational and promotional activities aimed at improving enrolment and retention rates in 15 communities in the Central and Eastern Regions (ERs) of Ghana. Observation, indepth interviews and informal conversations were used to collect qualitative data. Forty key informants (community members, health providers and district health insurance schemes’ [DHISs] staff) purposely selected from two casestudy communities in the Central Region (CR) were interviewed. Several community members, health providers and DHISs’ staff were also engaged in informal conversations in the other five communities in the region. Also, four staff of the Ministry of Health (MoH), Ghana Health Service (GHS) and National Health Insurance Authority (NHIA) were engaged in in-depth interviews. Descriptive statistics was used to analyse quantitative data. Qualitative data was analysed using thematic content analysis. Results: The results show that factors that influence enrolment and retention in the NHIS are multi-dimensional and cut across all stakeholders. People enrolled and renewed their membership because of NHIS’ benefits and health providers’ positive behaviour. Barriers to enrolment and retention included: poverty, traditional risk-sharing arrangements influence people to enrol or renew their membership only when they need healthcare, dissatisfaction about health providers’ behaviour and service delivery challenges. Conclusion: Given the multi-dimensional nature of barriers to enrolment and retention

Impaired precision, but normal retention, of auditory sensory ("echoic") memory information in schizophrenia.

Science.gov (United States)

Javitt, D C; Strous, R D; Grochowski, S; Ritter, W; Cowan, N

1997-05-01

Working memory is the type of memory that allows one to hold information in mind while working on a task or problem. The present study investigated attention-independent auditory sensory ("echoic") memory in 18 schizophrenic participants and 17 controls. Schizophrenic participants showed impaired delayed tone matching performance in comparison with controls. However, when groups were matched for performance at 1 s by varying the difficulty of the task across groups, schizophrenic participants showed normal retention of information as reflected in normal tone matching performance. These findings demonstrate that schizophrenic may be in the sensitivity of the system rather than the duration for which memory traces were retained.

Reliability-based design of a retaining wall

OpenAIRE

Kim, John Sang

1995-01-01

A retaining wall is subject to various limit states such as sliding, overturning and bearing capacity, and it can fail by anyone of them. Since a great deal of uncertainty is involved in the analysis of the limit states~ the use of detenninistic conventional safety factors may produce a misleading result. The main objective of this study is to develop a procedure for the optimum design of a retaining wall by using the reliability theory. Typical gravity retaining walls with fou...

31 CFR 203.16 - Retainer and investor depositaries.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Retainer and investor depositaries... TREASURY TAX AND LOAN PROGRAM PATAX § 203.16 Retainer and investor depositaries. (a) Credit to TIP main account balance. On the business day that the TSC receives an AOC from a retainer or investor depositary...

Use of the frontal process of the maxillary bone for implant placement to retain a nasal prosthesis: a clinical report.

Science.gov (United States)

Proussaefs, Periklis

2004-01-01

Implant placement to provide support and retention for nasal prostheses has been described in the literature. The anatomic sites that have been utilized for implant placement are the nasal bones, the premaxillary area through the nasal fossae, and the anterior wall of the frontal sinus. In the patient described, after a presurgical computerized tomography scan to determine adequacy of bone volume, 1 conventional threaded hydroxyapatite-coated root-form implant, created for intraoral use, was placed in the frontal process of the maxillary bone and 2 additional conventional implants were placed in the premaxillary area through the nasal fossa. Six months after implant placement, second-stage surgery was completed. A single bar connecting the 3 implants was fabricated. The removable nasal prosthesis was retained on the bar with 2 clips. An examination 1 year postsurgery revealed no clinical signs of pathosis. Long-term clinical follow-up of this case should continue and a sufficient number of additional cases should be investigated before use of the frontal process of the maxillary bone for implant retention can be recommended on a routine basis.

Dopamine antagonists during parturition disrupt maternal care and the retention of maternal behavior in rats.

Science.gov (United States)

Byrnes, Elizabeth M; Rigero, Beth A; Bridges, Robert S

2002-11-01

Brief contact with pups at parturition enables the female rat to establish and retain the full repertoire of maternal behaviors, allowing her to respond rapidly to pups in the future. To determine whether the dopamine system is involved in the retention of maternal behavior, females were continuously infused with dopamine antagonists during the periparturitional period and then allowed either a brief interaction period with pups (3 h) or no interaction with pups (pups removed as they were born). Females were exposed to either the D1-like antagonist SCH 23390 (0.1 or 1.0 mg/kg/day) or the D2-like antagonist clebopride (0.5 or 1.0 mg/kg/day). The high dose of either DA antagonist resulted in significant attenuation of maternal care immediately postpartum. When tested for the retention of maternal behavior 7 days later, however, only the females exposed to the D2 antagonist displayed a delayed response to shown full maternal behavior (FMB) towards donor pups. Thus, while both dopamine receptor subtypes appear necessary for the full and rapid expression of maternal behavior during the early postpartum period, only the D2 receptor subtype appears to be involved in the retention of this behavior.

Improving retention and motivation in non-clinical dialysis employees.

Science.gov (United States)

Campbell, Anne

2004-02-01

For no additional expense, little intrusion into the schedule or duties of the day, and no additional personnel to hire, dialysis facilities can make a dramatic impact on the training, motivation, and retention of employees through the use of classes designed specifically for the needs of newly employed non-clinical personnel. In today's world where many are expected to do a task with little or no orientation to the overall values and goals of the organization and how their tasks matter, what other action can accomplish so much for employee motivation and retention for so little time and expense? At DCI Mid-Missouri this program has been successful in retaining many excellent employees over many years and has been part of an ongoing effort to increase employees' interest and commitment to their work and the organization. It has also made them much more aware of treatments, other personnel and most of all, of our patients and their needs. It fulfills the needs of humans to be valued and have meaningful work. It contains costs and helps efficiency and productivity. Most of all, it keeps excellent people on the job and enjoying their work more than they would have. Participants' words when evaluating the most recent series of classes speak for themselves in demonstrating these important benefits that can be achieved easily in dialysis facilities throughout the United States and the world.

Retention of silica nanoparticles on calcium carbonate sands immersed in electrolyte solutions

KAUST Repository

Li, Yan Vivian

2014-12-01

© 2014 Elsevier Inc. Understanding nanoparticle-surface adhesion is necessary to develop inert tracers for subsurface applications. Here we show that nanoparticles with neutral surface charge may make the best subsurface tracers, and that it may be possible to used SiO2 nanoparticle retention to measure the fraction of solid surface that has positive charge. We show that silica nanoparticles dispersed in NaCl electrolyte solutions are increasingly retained in calcium carbonate (calcite) sand-packed columns as the solution ionic strength increases, but are not retained if they are injected in pure water or Na2SO4 electrolyte solutions. The particles retained in the NaCl experiments are released when the column is flushed with pure water or Na2SO4 solution. AFM measurements on calcite immersed in NaCl solutions show the initial repulsion of a silica colloidal probe as the surface is approached is reduced as the solution ionic strength increases, and that at high ionic strengths it disappears entirely and only attraction remains. These AFM measurements and their interpretation with Derjaguin-Landau-Verwey-Overbeek (DLVO) theory shows the calcite surface charge is always negative for Na2SO4 solutions, but changes from negative to positive in a patchy fashion as the ionic strength of the NaCl solution increases. Since mixed-charge (patchy) surfaces may be common in the subsurface, nanoparticles with near-zero charge may make the best tracers.

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

Science.gov (United States)

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

2017-12-01

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

Optimal methods for fitting probability distributions to propagule retention time in studies of zoochorous dispersal.

Science.gov (United States)

Viana, Duarte S; Santamaría, Luis; Figuerola, Jordi

2016-02-01

Propagule retention time is a key factor in determining propagule dispersal distance and the shape of "seed shadows". Propagules dispersed by animal vectors are either ingested and retained in the gut until defecation or attached externally to the body until detachment. Retention time is a continuous variable, but it is commonly measured at discrete time points, according to pre-established sampling time-intervals. Although parametric continuous distributions have been widely fitted to these interval-censored data, the performance of different fitting methods has not been evaluated. To investigate the performance of five different fitting methods, we fitted parametric probability distributions to typical discretized retention-time data with known distribution using as data-points either the lower, mid or upper bounds of sampling intervals, as well as the cumulative distribution of observed values (using either maximum likelihood or non-linear least squares for parameter estimation); then compared the estimated and original distributions to assess the accuracy of each method. We also assessed the robustness of these methods to variations in the sampling procedure (sample size and length of sampling time-intervals). Fittings to the cumulative distribution performed better for all types of parametric distributions (lognormal, gamma and Weibull distributions) and were more robust to variations in sample size and sampling time-intervals. These estimated distributions had negligible deviations of up to 0.045 in cumulative probability of retention times (according to the Kolmogorov-Smirnov statistic) in relation to original distributions from which propagule retention time was simulated, supporting the overall accuracy of this fitting method. In contrast, fitting the sampling-interval bounds resulted in greater deviations that ranged from 0.058 to 0.273 in cumulative probability of retention times, which may introduce considerable biases in parameter estimates. We

Implanted deuterium retention and release in carbon-coated beryllium

International Nuclear Information System (INIS)

Anderl, R.A.; Longhurst, G.R.; Pawelko, R.J.; Oates, M.A.

1997-01-01

Deuterium implantation experiments have been conducted on samples of clean and carbon-coated beryllium. These studies entailed preparation and characterization of beryllium samples coated with carbon thicknesses of 100, 500, and 1000 angstrom. Heat treatment of a beryllium sample coated with carbon to a thickness of approximately 100 angstrom revealed that exposure to a temperature of 400 degrees C under high vacuum conditions was sufficient to cause substantial diffusion of beryllium through the carbon layer, resulting in more beryllium than carbon at the surface. Comparable concentrations of carbon and beryllium were observed in the bulk of the coating layer. Higher than expected oxygen levels were observed throughout the coating layer as well. Samples were exposed to deuterium implantation followed by thermal desorption without exposure to air. Differences were observed in deuterium retention and postimplantation release behavior in the carbon-coated samples as compared with bare samples. For comparable implantation conditions (sample temperature of 400 degrees C and an incident deuterium flux of approximately 6 X 10 19 D/m 2 sec), the quantity of deuterium retained in the bare sample was less than that retained in the carbon-coated samples. Further, the release of the deuterium took place at lower temperatures for the bare beryllium surfaces than for carbon-coated beryllium samples. 4 refs., 8 figs., 1 tab

Prevention and management of postoperative urinary retention after urogynecologic surgery

Directory of Open Access Journals (Sweden)

Geller EJ

2014-08-01

Full Text Available Elizabeth J Geller Division of Female Pelvic Medicine and Reconstructive Surgery, Department of Obstetrics and Gynecology, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA Abstract: Postoperative urinary retention (POUR is a frequent consequence of gynecologic surgery, especially with surgical correction of urinary incontinence and pelvic organ prolapse. Estimates of retention rates after pelvic surgery range from 2.5%–43%. While there is no standard definition for POUR, it is characterized by impaired bladder emptying, with an elevation in the volume of retained urine. The key to management of POUR is early identification. All patients undergoing pelvic surgery, especially for the correction of incontinence or prolapse, should have an assessment of voiding function prior to discharge. There are several ways to assess voiding function – the gold standard is by measuring a postvoid residual. Management of POUR is fairly straightforward. The goal is to decompress the bladder to avoid long-term damage to bladder integrity and function. The decision regarding when to discontinue catheter-assisted bladder drainage in the postoperative period can be assessed in an ongoing fashion by measurement of postvoid residual. The rate of prolonged POUR beyond 4 weeks is low, and therefore most retention can be expected to resolve spontaneously within 4–6 weeks. When POUR does not resolve spontaneously, more active management may be required. Techniques include urethral dilation, sling stretching, sling incision, partial sling resection, and urethrolysis. While some risk of POUR is inevitable, there are risk factors that are modifiable. Patients that are at higher risk – either due to the procedures being performed or their clinical risk factors – should be counseled regarding the risks and management options for POUR prior to their surgery. Although POUR is a serious condition that can have serious consequences if left untreated, it

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

Science.gov (United States)

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