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Sample records for subsequent academic buoyancy

  1. Longitudinal modelling of academic buoyancy and motivation: do the '5Cs' hold up over time?

    Science.gov (United States)

    Martin, Andrew J; Colmar, Susan H; Davey, Louise A; Marsh, Herbert W

    2010-09-01

    Academic buoyancy is students' ability to successfully deal with setbacks and challenges that are typical of academic life. The present study extends previous preliminary cross-sectional work that tentatively identified five motivational predictors of academic buoyancy - referred to as the '5Cs' of academic buoyancy: confidence (self-efficacy), coordination (planning), commitment (persistence), composure (low anxiety), and control (low uncertain control). The study seeks to more clearly ascertain the effects of motivation (and its mediating role) on academic buoyancy over and above prior academic buoyancy. The study comprised N=1,866 high school students from six schools. Longitudinal data were collected (1 year apart) and the hypothesized model exploring longitudinal effects was tested using structural equation modelling. After controlling for prior variance in academic buoyancy, the 5Cs were significant predictors of subsequent academic buoyancy. Furthermore, over and above the direct effects of prior academic buoyancy on subsequent academic buoyancy, the 5Cs significantly mediated this relationship. The study concludes with a discussion of the substantive, applied, and methodological implications for researchers and practitioners seeking to investigate and address the academic buoyancy of students who require the capacity to effectively function in an ever-challenging school environment.

  2. Academic buoyancy and academic outcomes: towards a further understanding of students with attention-deficit/hyperactivity disorder (ADHD), students without ADHD, and academic buoyancy itself.

    Science.gov (United States)

    Martin, Andrew J

    2014-03-01

    Academic buoyancy is students' capacity to successfully overcome setback and challenge that is typical of the ordinary course of everyday academic life. It may represent an important factor on the psycho-educational landscape assisting students who experience difficulties in school and schoolwork. This study investigated the role of academic buoyancy in the achievement and cognitive, affective and behavioural engagement of (1) students with attention-deficit/hyperactivity disorder (ADHD) and (2) 'regular' (or 'general') students residing in the same classrooms and schools. The study also sought to extend prior research into academic buoyancy by including previously neglected and potentially influential factors such as personality and socio-economic status. Participants were n = 87 high school students with ADHD, n = 3374 non-ADHD peers, and n = 87 randomly drawn non-ADHD students. Survey-based data were analysed using multigroup (ADHD, non-ADHD, randomly weighted non-ADHD) multivariate (multiple independent/covariate and dependent variables) path analysis. The findings revealed a significant and positive association between academic buoyancy and outcomes for students with ADHD that generalized to non-ADHD groups. On occasion where academic buoyancy effects differed between the groups, effects favoured students with ADHD. Furthermore, academic buoyancy explained significant variance in outcomes for both groups of students after covariates (age, gender, parent education, language background, socio-economic status, personality) were entered. It is concluded that there is merit in widely promoting and fostering academic buoyancy among ADHD and non-ADHD students alike - and that academic buoyancy explains variance in outcomes beyond major intrapersonal factors such as personality, socio-economic status, ethnicity, and the like. © 2012 The British Psychological Society.

  3. Academic buoyancy, student's achievement, and the linking role of control: A cross-lagged analysis of high school students.

    Science.gov (United States)

    Collie, Rebecca J; Martin, Andrew J; Malmberg, Lars-Erik; Hall, James; Ginns, Paul

    2015-03-01

    Previous research has indicated that although academic buoyancy and student's achievement are associated, the relationship is relatively modest. We sought to determine whether another construct might link academic buoyancy and student's achievement. Based on prior theoretical and empirical work, we examined a sense of control as one possible linking mechanism. The study analysed data from 2,971 students attending 21 Australian high schools. We conducted a cross-lagged panel design as a first means of disentangling the relative salience of academic buoyancy, control, and achievement (Phase 1). Based upon these results, we proceeded with follow-up analyses of an ordered process model linking the constructs over time (Phase 2). Findings showed that buoyancy and achievement were associated with control over time, but not with one another (Phase 1). In addition, control appeared to play a role in how buoyancy influenced achievement and that a cyclical process may operate among the three factors over time (Phase 2). The findings suggest that control may play an important role in linking past experiences of academic buoyancy and achievement to subsequent academic buoyancy and achievement. © 2015 The British Psychological Society.

  4. Academic Buoyancy and Academic Outcomes: Towards a Further Understanding of Students with Attention-Deficit/Hyperactivity Disorder (ADHD), Students without ADHD, and Academic Buoyancy Itself

    Science.gov (United States)

    Martin, Andrew J.

    2014-01-01

    Background: Academic buoyancy is students' capacity to successfully overcome setback and challenge that is typical of the ordinary course of everyday academic life. It may represent an important factor on the psycho-educational landscape assisting students who experience difficulties in school and schoolwork. Aims: This study investigated the…

  5. Social Support, Academic Adversity and Academic Buoyancy: A Person-Centred Analysis and Implications for Academic Outcomes

    Science.gov (United States)

    Collie, Rebecca J.; Martin, Andrew J.; Bottrell, Dorothy; Armstrong, Derrick; Ungar, Michael; Liebenberg, Linda

    2017-01-01

    The present study employed person-centred analyses that enabled identification of groups of students separated on the basis of their perceptions of social support (home and community), academic support, academic adversity and academic buoyancy. Among a sample of 249 young people, including many from high-needs communities, cluster analysis…

  6. Academic Buoyancy in Secondary School: Exploring Patterns of Convergence in English, Mathematics, Science, and Physical Education

    Science.gov (United States)

    Malmberg, Lars-Erik; Hall, James; Martin, Andrew J.

    2013-01-01

    Past research into the ability of students to "bounce back" from everyday academic setback (academic buoyancy) has lacked sensitivity to the contexts in which children demonstrate this behavior. Here we aimed to contextualize past findings by reporting the results of an exploratory investigation that featured: (1) repeated measurement of…

  7. Academic Buoyancy Mediates Academic Anxiety's Effects on Learning Strategies: An Investigation of English- and Chinese-Speaking Australian Students

    Science.gov (United States)

    Collie, Rebecca J.; Ginns, Paul; Martin, Andrew J.; Papworth, Brad

    2017-01-01

    A primary goal our study was to explore whether relations between academic anxiety and students' use of a range of learning strategies (memorisation, elaboration, personal best [PB] goals and cooperation) were mediated by academic buoyancy. We were also interested in extending knowledge of anxiety and its role in students' learning strategy use.…

  8. Fitness Change and Subsequent Academic Performance in Adolescents

    Science.gov (United States)

    Chen, Li-Jung; Fox, Kenneth R.; Ku, Po-Wen; Taun, Chih-Yang

    2013-01-01

    Background: This study examined the association between fitness change and subsequent academic performance in Taiwanese schoolchildren from 7th grade to 9th grade. Methods: The 7th graders from 1 junior high school district participated in this study (N=669). Academic performance was

  9. Psycho-Educational Factors in the Prediction of Academic Buoyancy in Second Life®

    Science.gov (United States)

    Carrington, Cheril C.

    2013-01-01

    Academic resilience has been widely researched in traditional and online educational settings, but it has not been sufficiently studied in three-dimensional (3D) virtual learning environments (VLEs). This inferential research used multiple regression to quantitatively investigate the extent to which psycho-educational factors including academic…

  10. The effect of an intercalated BSc on subsequent academic performance.

    Science.gov (United States)

    Mahesan, Nishanthan; Crichton, Siobhan; Sewell, Hannah; Howell, Simon

    2011-10-03

    The choice of whether to undertake an intercalated Bachelor of Science (BSc) degree is one of the most important decisions that students must make during their time at medical school. An effect on exam performance would improve a student's academic ranking, giving them a competitive edge when applying for foundation posts. Retrospective data analysis of anonymised student records. The effects of intercalating on final year exam results, Foundation Programme score, application form score (from white-space questions), quartile rank score, and success with securing Foundation School of choice were assessed using linear and ordered logistic regression models, adjusted for course type, year of graduation, graduate status and baseline (Year 1) performance. The study included 1158 students, with 54% choosing to do an intercalated BSc, and 9.8% opting to do so at an external institution. Doing an intercalated BSc was significantly associated with improved outcome in Year 5 exams (P = 0.004). This was irrespective of the year students chose to intercalate, with no significant difference between those that intercalated after years 2, 3 and 4 (p = 0.3096). There were also higher foundation application scores (P BSc leads to an improvement in subsequent exam results and develops the skills necessary to produce a strong foundation programme application. It also leads to greater success with securing preferred Foundation School posts in students. Differences between internally- and externally-intercalating students may be due to varying course structures or greater challenge in adjusting to a new study environment.

  11. Personal Best (PB) and "Classic" Achievement Goals in the Chinese Context: Their Role in Predicting Academic Motivation, Engagement and Buoyancy

    Science.gov (United States)

    Yu, Kai; Martin, Andrew J.

    2014-01-01

    Prior research has shown personal best (PB) goals to be significantly related to students' motivation, engagement and achievement. However, research thus far has investigated PB goals only among Western samples and it is unclear to what extent PB goals hold academic merit in the Asian context. It is also unclear whether PB goals explain variance…

  12. The Impact of Participating in a Peer Assessment Activity on Subsequent Academic Performance

    Science.gov (United States)

    Jhangiani, Rajiv S.

    2016-01-01

    The present study investigates the impact of participation in a peer assessment activity on subsequent academic performance. Students in two sections of an introductory psychology course completed a practice quiz 1 week prior to each of three course exams. Students in the experimental group participated in a five-step double-blind peer assessment…

  13. Neutral Buoyancy Laboratory (NBL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Neutral Buoyancy Laboratory (NBL) is an astronaut training facility and neutral buoyancy pool operated by NASA and located at the Sonny Carter Training Facility,...

  14. The Association Between Early Marijuana Use and Subsequent Academic Achievement and Health Problems: A Longitudinal Study

    OpenAIRE

    Brook, Judith S.; Stimmel, Matthew A.; Zhang, Chenshu; Brook, David W.

    2008-01-01

    In this prospective longitudinal study, the authors investigated the association between marijuana use over a period of 13 years and subsequent health problems by age 30. A community sample of 749 participants from upstate New York were interviewed at mean ages of 14, 16, 22, and 27 years. Marijuana use over time was significantly associated with increased health problems by the late twenties, including respiratory problems, general malaise, neurocognitive problems, and lower academic achieve...

  15. Boasts are a boost: achievement prime self-reactivity predicts subsequent academic performance.

    Science.gov (United States)

    Gramzow, Richard H; Johnson, Camille S; Willard, Greg

    2014-03-01

    The present research tests the hypothesis that self-reactivity following an achievement prime reflects the strength of achievement goals and is a predictor of future goal-relevant performance. In Studies 1-3, undergraduates reported their grade-point averages (GPAs) following either an achievement goal prime or a control prime. Academic exaggeration (higher self-reported than official GPA) was the indicator of self-reactivity to the prime. Study 1 involved a direct achievement goal prime, whereas Studies 2 and 3 involved indirect priming techniques. In all 3 experiments, greater academic exaggeration following the achievement goal prime (but not the control prime) predicted better academic performance a semester later (based on official records). Study 4 demonstrated that the magnitude of students' GPA goals mediated the association between academic exaggeration and subsequent performance (1 year later). The fact that self-reactivity to a single achievement goal prime in the lab predicted later performance in "real life" suggests that individual differences in reactivity to a specific prime can signal much broader motivational orientations related to the primed goal. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

  16. The association between earlier marijuana use and subsequent academic achievement and health problems: a longitudinal study.

    Science.gov (United States)

    Brook, Judith S; Stimmel, Matthew A; Zhang, Chenshu; Brook, David W

    2008-01-01

    In this prospective longitudinal study, the authors investigated the association between marijuana use over a period of 13 years and subsequent health problems at age 27. A community sample of 749 participants from upstate New York was interviewed at mean ages of 14, 16, 22, and 27 years. Marijuana use over time was significantly associated with increased health problems by the late twenties, including respiratory problems, general malaise, neurocognitive problems, and lower academic achievement and functioning. Effective prevention and intervention programs should consider the wide range of adverse physiological and psychosocial outcomes associated with marijuana use over time.

  17. Exercise Equipment: Neutral Buoyancy

    Science.gov (United States)

    Shackelford, Linda; Valle, Paul

    2016-01-01

    Load Bearing Equipment for Neutral Buoyancy (LBE-NB) is an exercise frame that holds two exercising subjects in position as they apply counter forces to each other for lower extremity and spine loading resistance exercises. Resistance exercise prevents bone loss on ISS, but the ISS equipment is too massive for use in exploration craft. Integrating the human into the load directing, load generating, and motion control functions of the exercise equipment generates safe exercise loads with less equipment mass and volume.

  18. Do Academically Deficient Scholarship Athletes Earn Higher Wages Subsequent to Graduation?

    Science.gov (United States)

    Olbrecht, Alexandre

    2009-01-01

    In this paper, data from the Baccalaureate & Beyond 93/97/03 survey is used to estimate the effects on the earnings of scholarship athletics participants subsequent to graduation. Former college athletes are found to have higher wages on average. Upon first glance, colleges and universities could use these results to argue on behalf of investments…

  19. Structural and socio-psychological influences on adolescents' educational aspirations and subsequent academic achievement.

    Science.gov (United States)

    Rothon, Catherine; Arephin, Muna; Klineberg, Emily; Cattell, Vicky; Stansfeld, Stephen

    2011-06-01

    Previous literature indicates that educational aspirations are an important predictor of achievement at school and beyond. This paper examines the factors that are associated with high educational aspirations. It also looks at the relationship between aspirations and achievement at the General Certificate of Secondary Education in a deprived area of London. The results show that educational aspirations are associated with individual characteristics. Girls were more likely than boys to express a wish to remain in education beyond the age of 16. For the most academic route post-16, there were substantial ethnic differences, with minority ethnic groups generally being more likely to state a desire to follow this path. Students who were eligible for free school meals tended to have lower aspirations. Socio-psychological variables were also shown to be of importance, particularly self-esteem and psychological distress. Importantly, educational aspirations had a strong association with actual achievement at age 16, remaining associated even after controlling for a number of other variables, including prior achievement. These findings are discussed in light of previous research and potential intervention strategies.

  20. Does academic performance in the premedical year predict the performance of the medical student in subsequent years?

    Science.gov (United States)

    Al-Mazrou, Abdulrahman M

    2008-05-01

    Student admission into the College of Medicine at King Saud University (KSU) is dependent on the achievement of a grade point average (GPA) of ≥3.5 /5 by the end of the premedical year. This study was undertaken to ascertain whether pre-selected medical students who achieve a relatively low GPA (≤3.75/5) in the premedical year are at risk of having academic difficulties in subsequent years. A cross-sectional study of all students admitted to the College of Medicine at KSU during 5 academic years (1994 to 1998) was conducted in 2004. The likelihood of completing the program by 2004 and the dropout frequency were compared in the two groups based on their GPA in the premedical year: High GPA (>3.75) and Low GPA (≤3.75). During the study period, 739 students were admitted to the college. Of these, 619 (84%) were in High GPA group, and 120 (16%) in the Low GPA group. Of the students with High GPA, 545 (88%) out of 619 graduated compared with 79 (66%) of 120 in the Low GPA group (OR 3.822 [95% CI: 2.44, 5.99]: Pcolleges should help optimize the use of resources and reduce student wastage.

  1. Rigorous buoyancy driven bubble mixing for centrifugal microfluidics.

    Science.gov (United States)

    Burger, S; Schulz, M; von Stetten, F; Zengerle, R; Paust, N

    2016-01-21

    We present batch-mode mixing for centrifugal microfluidics operated at fixed rotational frequency. Gas is generated by the disk integrated decomposition of hydrogen peroxide (H2O2) to liquid water (H2O) and gaseous oxygen (O2) and inserted into a mixing chamber. There, bubbles are formed that ascent through the liquid in the artificial gravity field and lead to drag flow. Additionaly, strong buoyancy causes deformation and rupture of the gas bubbles and induces strong mixing flows in the liquids. Buoyancy driven bubble mixing is quantitatively compared to shake mode mixing, mixing by reciprocation and vortex mixing. To determine mixing efficiencies in a meaningful way, the different mixers are employed for mixing of a lysis reagent and human whole blood. Subsequently, DNA is extracted from the lysate and the amount of DNA recovered is taken as a measure for mixing efficiency. Relative to standard vortex mixing, DNA extraction based on buoyancy driven bubble mixing resulted in yields of 92 ± 8% (100 s mixing time) and 100 ± 8% (600 s) at 130g centrifugal acceleration. Shake mode mixing yields 96 ± 11% and is thus equal to buoyancy driven bubble mixing. An advantage of buoyancy driven bubble mixing is that it can be operated at fixed rotational frequency, however. The additional costs of implementing buoyancy driven bubble mixing are low since both the activation liquid and the catalyst are very low cost and no external means are required in the processing device. Furthermore, buoyancy driven bubble mixing can easily be integrated in a monolithic manner and is compatible to scalable manufacturing technologies such as injection moulding or thermoforming. We consider buoyancy driven bubble mixing an excellent alternative to shake mode mixing, in particular if the processing device is not capable of providing fast changes of rotational frequency or if the low average rotational frequency is challenging for the other integrated fluidic operations.

  2. Wave Dragon Buoyancy Regulation Study

    DEFF Research Database (Denmark)

    Jakobsen, Jens; Kofoed, Jens Peter

    Wave Dragon is a wave energy converter, which was deployed offshore at Nissum Bredning in Denmark in 2003. The experience gained from operating Wave Dragon during 2003 and 2004 has shown that the buoyancy regulation system can be improved in a number of ways. This study describes the current...... situation, and proposes a number of activities in order to improve the buoyancy regulation system. This work was performed under EU ENERGIE contract no. ENK5-CT-2002-00603, and is a contribution to WP 2.3/2.4 and D40/D41....

  3. Buoyancy effects on smoldering combustion

    Science.gov (United States)

    Dosanjh, S.; Peterson, J.; Fernandez-Pello, A. C.; Pagni, P. J.

    1985-01-01

    The effect of buoyancy on the rate of spread of a concurrent smolder reaction through a porous combustible material is investigated theoretically and experimentally. In the experiments, buoyant forces are controlled by varying the density difference, and the smolder rate spread through porous alpha cellulose (0.83 void fraction) is measured as a function of the ambient air pressure. The smolder velocity is found to increase with the ambient pressure; extinction occurs when the buoyancy forces cannot overcome the drag forces, indicating that diffusion by itself cannot support the spread of a smolder reaction. Theoretical predictions are found to be in good qualitative agreement with the experimental results.

  4. Does academic performance in the premedical year predict the performance of the medical student in subsequent years?

    Directory of Open Access Journals (Sweden)

    Abdulrahman M Al-Mazrou

    2008-01-01

    Conclusion: Our results support the prerequisite of a minimum GPA in the premedical year before proceeding to the higher levels. The GPA of premedical year is a useful predictor of students who need close monitoring and academic support. The use of GPA in the premedical year for admission into medical colleges should help optimize the use of resources and reduce student wastage.

  5. Buoyancy-Induced, Columnar Vortices

    Science.gov (United States)

    Simpson, Mark; Glezer, Ari

    2015-11-01

    Free buoyancy-induced, columnar vortices (dust devils) that are driven by thermal instabilities of ground-heated, stratified air in areas with sufficient insolation convert the potential energy of low-grade heat in the surface air layer into a vortex flow with significant kinetic energy. A variant of the naturally-occurring vortex is deliberately triggered and anchored within an azimuthal array of vertical, stator-like flow vanes that form an open-top enclosure and impart tangential momentum to the radially entrained air. This flow may be exploited for power generation by coupling the vortex to a vertical-axis turbine. The fundamental mechanisms associated with the formation, evolution, and dynamics of an anchored, buoyancy-driven columnar vortex within such a facility are investigated experimentally using a heated ground plane. Specific emphasis is placed on the manipulation of the vortex formation and structure and the dependence of the vorticity production and sustainment mechanisms on the thermal resources and characteristic scales of the anchoring flow vanes using stereo-PIV. It is shown that manipulation of the formation and advection of vorticity concentrations within the enclosure can be exploited for increasing the available kinetic energy. Supported by ARPA-E.

  6. Academic Performance in Children of Mothers With Schizophrenia and Other Severe Mental Illness, and Risk for Subsequent Development of Psychosis: A Population-Based Study

    Science.gov (United States)

    Lin, Ashleigh; Di Prinzio, Patsy; Young, Deidra; Jacoby, Peter; Whitehouse, Andrew; Waters, Flavie; Jablensky, Assen; Morgan, Vera A.

    2017-01-01

    Objective: We examined the academic performance at age 12 years of children of mothers diagnosed with schizophrenia or other severe mental illness using a large whole-population birth cohort born in Western Australia. We investigated the association between academic performance and the subsequent development of psychotic illness. Method: The sample comprised 3169 children of mothers with severe mental illness (schizophrenia, bipolar disorder, unipolar major depression, delusional disorder or other psychoses; ICD-9 codes 295–298), and 88 353 children of comparison mothers without known psychiatric morbidity. Academic performance of children was indexed on a mandatory state-wide test of reading, spelling, writing and numeracy. Results: A larger proportion of children (43.1%) of mothers with severe mental illness performed below the acceptable standard than the reference group (30.3%; children of mothers with no known severe mental illness). After adjusting for covariates, children of mothers with any severe mental illness were more likely than the reference group to perform below-benchmark on all domains except reading. For all children, poor spelling was associated with the later development of psychosis, but particularly for those at familial risk for severe mental illness (hazard ratio [HR] = 1.81; 95% CI for HR = 1.21, 2.72). Conclusions: Children of mothers with a severe mental illness are at increased risk for sub-standard academic achievement at age 12 years, placing these children at disadvantage for the transition to secondary school. For children with familial risk for severe mental illness, very poor spelling skills at age 12 years may be an indicator of risk for later psychotic disorder. PMID:27131155

  7. Academic Performance in Children of Mothers With Schizophrenia and Other Severe Mental Illness, and Risk for Subsequent Development of Psychosis: A Population-Based Study.

    Science.gov (United States)

    Lin, Ashleigh; Di Prinzio, Patsy; Young, Deidra; Jacoby, Peter; Whitehouse, Andrew; Waters, Flavie; Jablensky, Assen; Morgan, Vera A

    2017-01-01

    We examined the academic performance at age 12 years of children of mothers diagnosed with schizophrenia or other severe mental illness using a large whole-population birth cohort born in Western Australia. We investigated the association between academic performance and the subsequent development of psychotic illness. The sample comprised 3169 children of mothers with severe mental illness (schizophrenia, bipolar disorder, unipolar major depression, delusional disorder or other psychoses; ICD-9 codes 295-298), and 88 353 children of comparison mothers without known psychiatric morbidity. Academic performance of children was indexed on a mandatory state-wide test of reading, spelling, writing and numeracy. A larger proportion of children (43.1%) of mothers with severe mental illness performed below the acceptable standard than the reference group (30.3%; children of mothers with no known severe mental illness). After adjusting for covariates, children of mothers with any severe mental illness were more likely than the reference group to perform below-benchmark on all domains except reading. For all children, poor spelling was associated with the later development of psychosis, but particularly for those at familial risk for severe mental illness (hazard ratio [HR] = 1.81; 95% CI for HR = 1.21, 2.72). Children of mothers with a severe mental illness are at increased risk for sub-standard academic achievement at age 12 years, placing these children at disadvantage for the transition to secondary school. For children with familial risk for severe mental illness, very poor spelling skills at age 12 years may be an indicator of risk for later psychotic disorder. © The Author 2016. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  8. Academically buoyant students are less anxious about and perform better in high-stakes examinations.

    Science.gov (United States)

    Putwain, David W; Daly, Anthony L; Chamberlain, Suzanne; Sadreddini, Shireen

    2015-09-01

    Prior research has shown that test anxiety is negatively related to academic buoyancy, but it is not known whether test anxiety is an antecedent or outcome of academic buoyancy. Furthermore, it is not known whether academic buoyancy is related to performance on high-stakes examinations. To test a model specifying reciprocal relations between test anxiety and academic buoyancy and to establish whether academic buoyancy is related to examination performance. A total of 705 students in their final year of secondary education (Year 11). Self-report data for test anxiety and academic buoyancy were measured in two waves in Year 11. Examination performance was taken from the mean English, mathematics, and science scores from the high-stakes General Certificate of Secondary Education (GCSE) examinations taken at the end of Year 11. Measurement invariance was demonstrated for test anxiety and academic buoyancy across both waves of measurement. The worry component of test anxiety, but not the tension component, showed reciprocal relations with academic buoyancy. Worry predicted lower mean GCSE score and academic buoyancy predicted a higher mean GCSE score. Tension did not predict mean GCSE score. Academic buoyancy protects against the appraisal of examinations as threatening by influencing self-regulative processes and enables better examination performance. Worry, but not tension, shows a negative feedback loop to academic buoyancy. © 2015 The British Psychological Society.

  9. Neutral Buoyancy Simulator- NB38 -Space Telescope

    Science.gov (United States)

    1980-01-01

    The Hubble Space Telescope (HST) is a cooperative program of the European Space Agency (ESA) and the National Aeronautical and Space Administration (NASA) to operate a long-lived space-based observatory. It was the flagship mission of NASA's Great Observatories program. The HST program began as an astronomical dream in the 1940s. During the 1970s and 1980s, the HST was finally designed and built becoming operational in the 1990s. The HST was deployed into a low-Earth orbit on April 25, 1990 from the cargo bay of the Space Shuttle Discovery (STS-31). The design of the HST took into consideration its length of service and the necessity of repairs and equipment replacement by making the body modular. In doing so, subsequent shuttle missions could recover the HST, replace faulty or obsolete parts and be re-released. Pictured is MSFC's Neutral Buoyancy Simulator (NBS) that served as the test center for shuttle astronauts training for Hubble related missions. Shown are astronauts Bruce McCandless and Sharnon Lucid being fitted for their space suits prior to entering the NBS to begin training on the space telescope axial scientific instrument changeout.

  10. Thermal buoyancy on Venus - Underthrusting vs subduction

    Science.gov (United States)

    Burt, Jeffrey D.; Head, James W.

    1992-01-01

    The thermal and buoyancy consequences of the subduction endmember are modeled in an attempt to evaluate the conditions distinguishing underthrusting and subduction. Thermal changes in slabs subducting into the Venusian mantle with a range of initial geotherms are used to predict density changes and, thus, slab buoyancy. Based on a model for subduction-induced mantle flow, it is then argued that the angle of the slab dip helps differentiate between underthrusting and subduction. Mantle flow applies torques to the slab which, in combination with torques due to slab buoyancy, act to change the angle of slab dip.

  11. Non-Uniqueness of the Point of Application of the Buoyancy Force

    Science.gov (United States)

    Kliava, Janis; Megel, Jacques

    2010-01-01

    Even though the buoyancy force (also known as the Archimedes force) has always been an important topic of academic studies in physics, its point of application has not been explicitly identified yet. We present a quantitative approach to this problem based on the concept of the hydrostatic energy, considered here for a general shape of the…

  12. Lithospheric buoyancy and continental intraplate stresses

    Science.gov (United States)

    Zoback, M.L.; Mooney, W.D.

    2003-01-01

    Lithospheric buoyancy, the product of lithospheric density and thickness, is an important physical property that influences both the long-term stability of continents and their state of stress. We have determined lithospheric buoyancy by applying the simple isostatic model of Lachenbruch and Morgan (1990). We determine the crustal portion of lithospheric buoyancy using the USGS global database of more than 1700 crustal structure determinations (Mooney et al., 2002), which demonstrates that a simple relationship between crustal thickness and surface elevation does not exist. In fact, major regions of the crust at or near sea level (0-200 m elevation) have crustal thicknesses that vary between 25 and 55 km. Predicted elevations due to the crustal component of buoyancy in the model exceed observed elevations in nearly all cases (97% of the data), consistent with the existence of a cool lithospheric mantle lid that is denser than the asthenosphere on which it floats. The difference between the observed and predicted crustal elevation is assumed to be equal to the decrease in elevation produced by the negative buoyancy of the mantle lid. Mantle lid thickness was first estimated from the mantle buoyancy and a mean lid density computed using a basal crust temperature determined from extrapolation of surface heat flow, assuming a linear thermal gradient in the mantle lid. The resulting values of total lithosphere thickness are in good agreement with thicknesses estimated from seismic data, except beneath cratonic regions where they are only 40-60% of the typical estimates (200-350 km) derived from seismic data. This inconsistency is compatible with petrologic data and tomography and geoid analyses that have suggested that cratonic mantle lids are ??? 1% less dense than mantle lids elsewhere. By lowering the thermally determined mean mantle lid density in cratons by 1%, our model reproduces the observed 200-350+ km cratonic lithospheric thickness. We then computed

  13. Energy spectrum of buoyancy-driven turbulence

    KAUST Repository

    Kumar, Abhishek

    2014-08-25

    Using high-resolution direct numerical simulation and arguments based on the kinetic energy flux Πu, we demonstrate that, for stably stratified flows, the kinetic energy spectrum Eu(k)∼k-11/5, the potential energy spectrum Eθ(k)∼k-7/5, and Πu(k)∼k-4/5 are consistent with the Bolgiano-Obukhov scaling. This scaling arises due to the conversion of kinetic energy to the potential energy by buoyancy. For weaker buoyancy, this conversion is weak, hence Eu(k) follows Kolmogorov\\'s spectrum with a constant energy flux. For Rayleigh-Bénard convection, we show that the energy supply rate by buoyancy is positive, which leads to an increasing Πu(k) with k, thus ruling out Bolgiano-Obukhov scaling for the convective turbulence. Our numerical results show that convective turbulence for unit Prandt number exhibits a constant Πu(k) and Eu(k)∼k-5/3 for a narrow band of wave numbers. © 2014 American Physical Society.

  14. Examining the relationship between childhood health conditions and health service utilisation at school entry and subsequent academic performance in a large cohort of Australian children.

    Science.gov (United States)

    Nasuuna, Esther; Santoro, Giuseppe; Kremer, Peter; de Silva, Andrea M

    2016-07-01

    Chronic health conditions are associated with poor academic outcomes. This study examines the relationship between health conditions, specialist health service utilisation and academic performance in Australian children. This was a quasi-longitudinal study where School Entrant Health Questionnaire (a survey tool with parent report on children's health) data for 24 678 children entering school in 2008 was matched with the 2011 National Assessment Program - Literacy and Numeracy (NAPLAN). Linear and logistic regressions were used to examine associations between health conditions, use of a specialist health service and reading and numeracy scores. The study comprised 24 678 children. Children with allergies, very low birth weight, developmental delay, diabetes, spina bifida, cystic fibrosis, birth abnormality, speech problems, intellectual disability and attention-deficit/hyperactivity disorder had lower numeracy scores than those without any of these conditions (P performance from those that had not used specialist health services. Some health conditions put children at risk of poorer academic performance, and interventions to prevent this such as appropriate support services in schools should be considered. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).

  15. Buoyancy Driven Natural Ventilation through Horizontal Openings

    DEFF Research Database (Denmark)

    Heiselberg, Per; Li, Zhigang

    2009-01-01

    An experimental study of the phenomenon of buoyancy driven natural ventilation through single-sided horizontal openings was performed in a full-scale laboratory test rig. The measurements were made for opening ratios L/D ranging from 0.027 to 4.455, where L and D are the length of the opening...... and the diameter of the opening, respectively. The basic nature of airflow through single-sided openings, including airflow rate, air velocity, temperature difference between the rooms and the dimensions of the horizontal openings, were measured. A bi-directional airflow rate was measured using the constant...... quite well with the Epstein's formula but in other cases the measured data show clear deviations from the Epstein's formula. Thus, revised formulas for natural ventilation are proposed....

  16. Buoyancy Driven Natural Ventilation through Horizontal Openings

    DEFF Research Database (Denmark)

    Heiselberg, Per

    2009-01-01

    An experimental study of the phenomenon of buoyancy driven natural ventilation through single-sided horizontal openings was performed in a full-scale laboratory test rig. The measurements were made for opening ratios L/D ranging from 0.027 to 4.455, where L and D are the length of the opening...... and the diameter of the opening, respectively. The basic nature of airflow through single-sided openings, including airflow rate, air velocity, temperature difference between the rooms and the dimensions of the horizontal openings, were measured. A bi-directional airflow rate was measured using the constant...... quite well with the Epstein's formula ratio are presented. In some cases the measured airflow rates fit quite well with the Epstein's formula but in other cases the measured data show clear deviations from the Epstein's formula. Thus, revised formulas for natural ventilation are proposed....

  17. Microgravity Flow Regime Data: Buoyancy and Mixing Apparatus Effects

    Science.gov (United States)

    Shephard, Adam; Best, Frederick

    2010-01-01

    Zero-g two-phase flow data set qualification and flight experiment design have not been standardized and as a result, agreement among researchers has not been reached regarding what experimental conditions adequately approximate those of microgravity. The effects of buoyancy forces and mixing apparatus on the flow regime transitions are presented in this study. The gravity conditions onboard zero-g aircraft are at best 10-3 g which is used to approximate the 10-5 g conditions of microgravity, thus the buoyancy forces present on zero-g aircraft can become significantly large and unrepresentative of microgravity. When buoyancy forces approach those of surface tension forces, buoyancy induced coalescence occurs. When discussing flow regime transitions, these large buoyancy forces lead to flow regime transitions which otherwise would not occur. The buoyancy attributes of the two-phase flow data sets available in the literature are evaluated to determine which data sets exhibit buoyancy induced transitions. Upon comparison of the representative data sets, the affects of different mixing apparatus can be seen in the superficial velocity flow regime maps.

  18. Neutral Buoyancy Simulator - NB32 - Large Space Structure

    Science.gov (United States)

    1980-01-01

    The Hubble Space Telescope (HST) is a cooperative program of the European Space Agency (ESA) and the National Aeronautical and Space Administration (NASA) to operate a long-lived space-based observatory; it was the flagship mission of NASA's Great Observatories program. The HST program began as an astronomical dream in the 1940s. During the 1970s and 1980s, HST was finally designed and built; and it finally became operational in the 1990s. HST was deployed into a low-Earth orbit on April 25, 1990 from the cargo bay of the Space Shuttle Discovery (STS-31). The design of the HST took into consideration its length of service and the necessity of repairs and equipment replacement by making the body modular. In doing so, subsequent shuttle missions could recover the HST, replace faulty or obsolete parts and be re-released. MSFC's Neutral Buoyancy Simulator served as the training facility for shuttle astronauts for Hubble related missions. Shown is astronaut Sharnon Lucid having her life support system being checked prior to entering the NBS to begin training on the space telescope axial scientific instrument changeout.

  19. Developing students’ learning achievement and experimental skills on buoyancy and the involvement of Newton’s third law through experimental sets

    Science.gov (United States)

    Chokchai, Jaewijarn; Khanti, Toedtanya; Sura, Wuttiprom

    2017-09-01

    The purposes of this research were: to construct packages of operations on buoyancy and the involvement of Newton’s third law, to enhance achievement score of students on buoyancy and the involvement of Newton’s third law, to enhance experimental skills on buoyancy and the involvement of Newton’s third law and to evaluate students’ attitude towards the packages of operations on buoyancy and the involvement of Newton’s third law using inquiry method. The samples were 42 grade 11 students in academic year 2016 at Hatyaiwittayalai School, Hatyai, Songkhla. The research method was one group pretest-posttest design. The research tools consisted of experimental set on buoyancy and the involvement of Newton’s third law, the learning achievement test on buoyancy and the involvement of Newton’s third law and the students’ attitude questionnaires. The experimental skills of most students was in a good level . The satisfaction of most students was in a good level. The research showed the learning achievement after instruction higher than that before instruction using experimental set at the significant level of 0.05 and the class average normalized gain is in the medium gain

  20. TAO/TRITON, RAMA, and PIRATA Buoys, Monthly, Buoyancy Flux

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset has monthly Buoyancy Flux data from the TAO/TRITON (Pacific Ocean, http://www.pmel.noaa.gov/tao/), RAMA (Indian Ocean,...

  1. Buoyancy-generated variable-density turbulence

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval, D.L.; Clark, T.T.; Riley, J.J.

    1996-07-01

    Because of the importance of turbulence mixing in many applications, a number of turbulence mixing models have been proposed for variable- density flows. These engineering models (one- point statistical models) typically include the transport of the turbulent kinetic energy and the turbulent energy dissipation rate (i.e., k - {epsilon} models). The model presented by Besnard, Harlow, Rauenzahn and Zemach (1992) (herein referred to as BHRZ) is a one-point model intended to describe variable-density turbulent flows. Transport equations for the Reynolds stress tensor, R{sub ij}, and the turbulent energy dissipation rate, the density-velocity correlation, a{sub i}, and the density-specific volume correlation, b are derived. This model employs- techniques and concepts from incompressible, constant- density turbulence modeling and incorporates ideas from two-phase flow models. Clark and Spitz (1994) present a two-point model for variable-density turbulence. Their derivation is based on transport equations that, are based 0481 on two-point- generalizations of R{sub ij}, a{sub ij}, and b. These equations are Fourier transformed with respect to the separation distance between the two points. Transport equations are derived for R{sub ij}, a{sub i}, b. As in the one-point model, this model contains many ad-hoc assumptions and unknown model coefficients that must be determined by comparison with experimental and numerical data. However, the two-point formalism requires fewer equilibrium assumptions then does a single-point model. Our primary concern in this paper lies in the nonlinear processes of turbulence and the influence of large density variations (not within the Boussinesq limit) on these processes. To. isolate the effects of variable-density on the turbulence we restrict our flow to be incompressible, statistically homogeneous buoyancy-generated. turbulence. To our knowledge there have not been any simulations reported for this problem.

  2. Neutral Buoyancy Test - Large Space Structure

    Science.gov (United States)

    1979-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. Construction methods had to be efficient due to the limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. With the help of the NBS, building a space station became more of a reality. In a joint venture between NASA/Langley Research Center in Hampton, Virginia and the MSFC, the Assembly Concept for Construction of Erectable Space Structures (ACCESS) was developed and demonstrated at MSFC's NBS. The primary objective of this experiment was to test the ACCESS structural assembly concept for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction. Pictured is a demonstration of ACCESS.

  3. Neutral Buoyancy Simulator Test - Scientific Airlock

    Science.gov (United States)

    1977-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. Construction methods had to be efficient due to the limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. With the help of the NBS, building a space station became more of a reality. Pictured is Astronaut Paul Weitz training on a mock-up of Spacelab's airlock-hatch cover. Training was also done on the use of foot restraints which had recently been developed to help astronauts maintain their positions during space walks rather than having their feet float out from underneath them while they tried to perform maintenance and repair operations. Every aspect of every space mission was researched and demonstrated in the NBS. Using the airlock hatch cover and foot restraints were

  4. Tidal tomography constrains Earth’s deep-mantle buoyancy

    Science.gov (United States)

    Lau, Harriet C. P.; Mitrovica, Jerry X.; Davis, James L.; Tromp, Jeroen; Yang, Hsin-Ying; Al-Attar, David

    2017-11-01

    Earth’s body tide—also known as the solid Earth tide, the displacement of the solid Earth’s surface caused by gravitational forces from the Moon and the Sun—is sensitive to the density of the two Large Low Shear Velocity Provinces (LLSVPs) beneath Africa and the Pacific. These massive regions extend approximately 1,000 kilometres upward from the base of the mantle and their buoyancy remains actively debated within the geophysical community. Here we use tidal tomography to constrain Earth’s deep-mantle buoyancy derived from Global Positioning System (GPS)-based measurements of semi-diurnal body tide deformation. Using a probabilistic approach, we show that across the bottom two-thirds of the two LLSVPs the mean density is about 0.5 per cent higher than the average mantle density across this depth range (that is, its mean buoyancy is minus 0.5 per cent), although this anomaly may be concentrated towards the very base of the mantle. We conclude that the buoyancy of these structures is dominated by the enrichment of high-density chemical components, probably related to subducted oceanic plates or primordial material associated with Earth’s formation. Because the dynamics of the mantle is driven by density variations, our result has important dynamical implications for the stability of the LLSVPs and the long-term evolution of the Earth system.

  5. Buoyancy-stirring interactions in a subtropical embayment: a ...

    African Journals Online (AJOL)

    ... were ~2–3 °C higher than those observed. The model also underestimated the intensity of stratification in the wet season. These shortcomings all suggest an overestimate of vertical mixing by the model's turbulence closure scheme. Keywords: buoyancy; density gradient; Maputo Bay; seasonal variation; subtropical zone; ...

  6. Using Surface Integrals for Checking Archimedes' Law of Buoyancy

    Science.gov (United States)

    Lima, F. M. S.

    2012-01-01

    A mathematical derivation of the force exerted by an "inhomogeneous" (i.e. compressible) fluid on the surface of an "arbitrarily shaped" body immersed in it is not found in the literature, which may be attributed to our trust in Archimedes' law of buoyancy. However, this law, also known as Archimedes' principle (AP), does not yield the force…

  7. Semi-Empirical Models for Buoyancy-Driven Ventilation

    DEFF Research Database (Denmark)

    Terpager Andersen, Karl

    2015-01-01

    A literature study is presented on the theories and models dealing with buoyancy-driven ventilation in rooms. The models are categorised into four types according to how the physical process is conceived: column model, fan model, neutral plane model and pressure model. These models are analysed...

  8. Experimental study of buoyancy driven natural ventilation through horizontal openings

    DEFF Research Database (Denmark)

    Heiselberg, Per; Li, Zhigang

    2007-01-01

    An experimental study of buoyancy driven natural ventilation through single-sided horizontal openings was performed in a full-scale laboratory test rig. Measurements were made for opening ratios L/D range from 0.027 to 4.455, where L and D are the length and the diameter of the opening, respectiv...

  9. Doubly diffusive magnetic buoyancy instability in the solar interior

    Science.gov (United States)

    Schmitt, J. H. M. M.; Rosner, R.

    1983-01-01

    An investigation of the buoyancy of diffuse magnetic fields has shown that in the presence of rotation, static equilibrium configurations of the toroidal magnetic field and ambient plasma can exist. In that case, the escape of toroidal magnetic flux from the solar interior may be determined by the growth of instabilities which the equilibrium configuration may be subject to. In connection with the present investigation, it is assumed that in the region of toroidal magnetic flux amplification, the magnetic field has not as yet filamented into flux ropes, and is therefore 'diffuse'. A study is conducted of the MHD stability of an electrically conducting and differentially rotating gas in the presence of a toroidal magnetic field, an external constant gravitational field, and radiance pressure. The full dispersion relation for the magnetic buoyancy problem is developed, and the solutions of the dispersion relation are discussed.

  10. Floating rings in vertical soap films : capillary driven bidimensional buoyancy

    CERN Document Server

    Adami, N

    2013-01-01

    The present study aims to investigate the motion of buoyant rings in vertical soap films. Thickness differences and related bi-dimensional densities are considered as the motor leading to bi-dimensional buoyancy. We show how this effect can be re-interpreted thanks to surface tension profiles in soap films. We propose a model involving surface tension profiles in order to describe the motion of buoyant particles in vertical soap films, and compare it to experimental data.

  11. Geodynamic modelling of low-buoyancy thermo-chemical plumes

    Science.gov (United States)

    Dannberg, Juliane; Sobolev, Stephan

    2015-04-01

    The Earth's biggest magmatic events that form Large Igneous Provinces are believed to originate from massive melting when hot mantle plumes rising from the lowermost mantle reach the base of the lithosphere. Classical models of thermal mantle plumes predict a flattening of the plume head to a disk-like structure, a kilometer-scale surface uplift just before the initiation of LIPs and thin plume tails. However, there are seismic observations and paleo-topography data that are difficult to explain with this classical approach. Here, using numerical models, we show that the issue can be resolved if major mantle plumes are thermo-chemical rather than purely thermal. It has been suggested a long time ago that subducted oceanic crust could be recycled by mantle plumes; and based on geochemical data, they may contain up to 15-20% of this recycled material in the form of dense eclogite, which drastically decreases their buoyancy and makes it depth-dependent. We perform numerical experiments in a 3D spherical shell geometry to investigate the dynamics of the plume ascent, the interaction between plume- and plate-driven flow and the dynamics of melting in a plume head. For this purpose, we use the finite-element code ASPECT, which allows for complex temperature-, pressure- and composition-dependent material properties. Moreover, our models incorporate phase transitions (including melting) with the accompanying rheological and density changes, Clapeyron slopes and latent heat effects for both peridotite and eclogite, mantle compressibility and a strong temperature- and depth-dependent viscosity. We demonstrate that despite their low buoyancy, such plumes can rise through the whole mantle causing only negligible surface uplift. Conditions for this ascent are high plume volume and moderate lower mantle subadiabaticity. While high plume buoyancy results in plumes directly advancing to the base of the lithosphere, plumes with slightly lower buoyancy pond in a depth of 300-400 km

  12. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei

    OpenAIRE

    Itsumi Nakamura; Carl G. Meyer; Katsufumi Sato

    2015-01-01

    We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two specie...

  13. Buoyancy Effects on Flow Transition in Low-Density Inertial Gas Jets

    Science.gov (United States)

    Pasumarthi, Kasyap S.; Agrawal, Ajay K.

    2005-01-01

    Effects of buoyancy on transition from laminar to turbulent flow are presented for momentum-dominated helium jet injected into ambient air. The buoyancy was varied in a 2.2-sec drop tower facility without affecting the remaining operating parameters. The jet flow in Earth gravity and microgravity was visualized using the rainbow schlieren deflectometry apparatus. Results show significant changes in the flow structure and transition behavior in the absence of buoyancy.

  14. Buoyancy effect on heat transfer in rotating smooth square U-duct at high rotation number

    Directory of Open Access Journals (Sweden)

    Yang Li

    2014-09-01

    Full Text Available The buoyancy effect on heat transfer in a rotating, two-pass, square channel is experimentally investigated in current work. The classical copper plate technique is performed to measure the regional averaged heat transfer coefficients. In order to perform a fundamental research, all turbulators are removed away. Two approaches of altering Buoyancy numbers are selected: varying rotation number from 0 to 2.08 at Reynolds number ranges of 10000 to 70000, and varying inlet density ratio from 0.07 to 0.16 at Reynolds number of 10000. And thus, Buoyancy numbers range from 0 to 12.9 for both cases. According to the experimental results, the relationships between heat transfer and Buoyancy numbers are in accord with those obtained under different rotation numbers. For both leading and trailing surface, a critical Buoyancy number exists for each X/D location. Before the critical point, the effect of Buoyancy number on heat transfer is limited; but after that, the Nusselt number ratios show different increase rate. Given the same rotation number, higher wall temperature ratios with its corresponding higher Buoyancy numbers substantially enhance heat transfer on both passages. And the critical exceed-point that heat transfer from trailing surface higher than leading surface happens at the same Buoyancy number for different wall temperature ratios in the second passage. Thus, the stronger buoyancy effect promotes heat transfer enhancement at high rotation number condition.

  15. How gas buoyancy creates shallow-zone geopressures

    Energy Technology Data Exchange (ETDEWEB)

    Herkommer, M.A. (Petrospec Computer Corp., Richardson, TX (United States))

    1993-10-01

    Within a buried formation, the difference between pore pressure in the top and the bottom of the zone is less if the formation contains gas than if it is liquid-filled. Consequently, if the zone is sufficiently thick, the driller can encounter gas pressures significantly higher than expected, when drilling into the top of the zone. Because this pressure would exceed that generated by a normal liquid pressure gradient for the well, the upper portion of the zone is thus geopressured. If unexpectedly encountered at shallow depths, such geopressures can create serious well control problems. This phenomenon is due to the lower density of gas, compared to liquid. It is the same principle which makes the surface pressure of a gas well much closer to bottomhole pressure than if the tubing were full of liquid. This article describes it as the buoyancy effect caused by the gas displacing, and thus floating upon, the formation liquid. The following discussion illustrates the effects with depth and formation thickness, and introduces computer-based methods for estimating and preparing for potential well control problems in shallow gas zones. For shallow gas reservoirs, correcting for buoyancy effect in an existing geopressure estimate by analyzing petrophysical and geophysical data can help optimize use of drilling mud, as well as improve casing design. Safety, economic and environmental risks related to loss of control, struck pipe and lost circulation are significant enough to warrant the cost of thorough geopressure estimation.

  16. The Causal Ordering of Self-Concept and Academic Motivation and Its Effect on Academic Achievement

    Science.gov (United States)

    Green, Jasmine; Nelson, Genevieve; Martin, Andrew J.; Marsh, Herb

    2006-01-01

    Critical questions in educational psychology research to be addressed in this paper concern the casual relationship between academic self-concept, academic motivation and its effect on academic achievement. Do changes in academic self-concept and academic motivation lead to changes in subsequent academic achievement? Various studies have attempted…

  17. Role of buoyancy and heat release in fire modeling, propagation, and instability

    Science.gov (United States)

    Shahid M. Mughal; Yousuff M. Hussaini; Scott L. Goodrick; Philip Cunningham

    2007-01-01

    In an investigation of the dynamics of coupled fluid-combustion-buoyancy driven problems, an idealised model formulation is used to investigate the role of buoyancy and heat release in an evolving boundary layer, with particular emphasis on examining underlying fluid dynamics to explain observed phenomena arising in forest fire propagation. The role played by the...

  18. Variable buoyancy system for unmanned multi-domain vehicles

    Science.gov (United States)

    MacLeod, Marc; Bryant, Matthew

    2016-04-01

    This paper presents the system design, construction, and testing of an active variable buoyancy system (VBS) actuator with applications to unmanned multi-domain vehicles. Unmanned multi-domain vehicles require nontraditional VBS designs because of their unique operation requirements. We present a VBS actuator design that targets multi-domain vehicle design objectives of high endurance, stealth, and underwater loitering. The design features a rigid ballast tank with an inner elastic bladder connected to a hydraulic pump and a proportionally controlled vent valve. The system working fluid is obtained from the ambient surrounding water and the elastic bladder separates the water from pressurized gas, thus preventing any gas from escaping during a venting operation. An analytic model of the VBS characterizing the system dynamics is derived. Ballast tank prototype design and construction is discussed. A VBS test platform vehicle is presented, featuring two ballast tanks, motor, pump, and RF receiver for control.

  19. Nonlinear dynamics of a buoyancy-induced turbulent fire

    Science.gov (United States)

    Takagi, Kazushi; Gotoda, Hiroshi; Tokuda, Isao T.; Miyano, Takaya

    2017-11-01

    We conduct a numerical study on the dynamic behavior of a buoyancy-induced turbulent fire from the viewpoints of symbolic dynamics, complex networks, and statistical complexity. Here, we consider two classes of entropies: the permutation entropy and network entropy in ɛ -recurrence networks, both of which evaluate the degree of randomness in the underlying dynamics. These entropies enable us to capture the significant changes in the dynamic behavior of flow velocity fluctuations. The possible presence of two important dynamics, low-dimensional deterministic chaos in the near field dominated by the motion of large-scale vortices and high-dimensional chaos in the far field forming a well-developed turbulent plume, is clearly identified by the multiscale complexity-entropy causality plane.

  20. Buoyancy induced Couette-Poiseuille flow in a vertical microchannel

    Science.gov (United States)

    Narahari, M.

    2017-10-01

    The fully developed buoyancy-induced (natural convective) Couette-Poiseuille flow in a vertical microchannel is investigated with the velocity slip and temperature jump boundary conditions. Closed form analytical solutions for the velocity and temperature fields are obtained. The effects of the fluid-wall interaction parameter, wall-ambient temperature difference ratio, Knudsen number, mixed convection parameter, and the dimensionless pressure gradient on the velocity, temperature, volume flow rate, heat flux between the plates and the Nusselt number have been discussed in detail through graphs. The outcomes of the investigation indicate that the volume flow rate increases with increasing values of mixed convection parameter, wall-ambient temperature difference ratio, and Knudsen number.

  1. Modeling the Buoyancy System of a Wave Energy Power Plant

    DEFF Research Database (Denmark)

    Pedersen, Tom S.; Nielsen, Kirsten M.

    2009-01-01

    A nonlinear dynamic model of the buoyancy system in a wave energy power plant is presented. The plant ("Wave Dragon") is a floating device using the potential energy in overtopping waves to produce power. A water reservoir is placed on top of the WD, and hydro turbines lead the water to the sea...... producing electrical power. Through air chambers it is possible to control the level of the WD. It is important to control the level in order to maximize the power production in proportion to the wave height, here the amount of overtopping water and the amount of potential energy is conflicting....... The pressures in the air chambers may be individually controlled by an air fan through an array of valves. The paper presents a model describing the dynamics from the air inlet to the level. Results from validation of the model against plant data are presented....

  2. Matching Subsequences in Trees

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li

    2009-01-01

    Given two rooted, labeled trees P and T the tree path subsequence problem is to determine which paths in P are subsequences of which paths in T. Here a path begins at the root and ends at a leaf. In this paper we propose this problem as a useful query primitive for XML data, and provide new...

  3. Large eddy simulation of a buoyancy-aided flow in a non-uniform channel – Buoyancy effects on large flow structures

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Y. [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom); School of Mechanical, Aerospace and Civil Engineering, University of Manchester, Manchester M13 9PL (United Kingdom); He, S., E-mail: s.he@sheffield.ac.uk [Department of Mechanical Engineering, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2017-02-15

    Highlights: • Buoyancy may greatly redistribute the flow in a non-uniform channel. • Flow structures in the narrow gap are greatly changed when buoyancy is strong. • Large flow structures exist in wider gap, which is enhanced when heat is strong. • Buoyancy reduces mixing factor caused by large flow structures in narrow gap. - Abstract: It has been a long time since the ‘abnormal’ turbulent intensity distribution and high inter-sub-channel mixing rates were observed in the vicinity of the narrow gaps formed by the fuel rods in nuclear reactors. The extraordinary flow behaviour was first described as periodic flow structures by Hooper and Rehme (1984). Since then, the existences of large flow structures were demonstrated by many researchers in various non-uniform flow channels. It has been proved by many authors that the Strouhal number of the flow structure in the isothermal flow is dependent on the size of the narrow gap, not the Reynolds number once it is sufficiently large. This paper reports a numerical investigation on the effect of buoyancy on the large flow structures. A buoyancy-aided flow in a tightly-packed rod-bundle-like channel is modelled using large eddy simulation (LES) together with the Boussinesq approximation. The behaviour of the large flow structures in the gaps of the flow passage are studied using instantaneous flow fields, spectrum analysis and correlation analysis. It is found that the non-uniform buoyancy force in the cross section of the flow channel may greatly redistribute the velocity field once the overall buoyancy force is sufficiently strong, and consequently modify the large flow structures. The temporal and axial spatial scales of the large flow structures are influenced by buoyancy in a way similar to that turbulence is influenced. These scales reduce when the flow is laminarised, but start increasing in the turbulence regeneration region. The spanwise scale of the flow structures in the narrow gap remains more or

  4. The Academic Publishing Industry

    DEFF Research Database (Denmark)

    Nell, Phillip Christopher; Wenzel, Tim Ole; Schmidt, Florian

    2014-01-01

    The case starts with introducing the outstanding profitability of academic journal publishers such as Elsevier and then dives into describing the research process from an idea to conducting research and to publishing the results in academic journals. Subsequently, demand and supply for scientific...

  5. Dispersion and dissolution of a buoyancy driven gas plume in a layered permeable rock

    Science.gov (United States)

    Woods, Andrew W.; Norris, Simon

    2016-04-01

    Using a series of simplified models, we explore the controls on the migration, dispersion and eventual dissolution of a plume of hydrogen gas which may, in principle, rise under buoyancy through a layered permeable rock if released from a Geological Disposal Facility (GDF). We show that the presence of low permeability shale barriers causes the gas to spread laterally as it rises. Averaging over the length scale of the barriers, we use expressions for the Darcy velocity of the gas to describe the dispersion of a tracer and illustrate the effect with a new experiment using a baffled Hele-Shaw cell. While the plume is flowing, a large volume of gas may build up beneath the barriers. If the gas flux subsequently wanes, much of the gas will drain upward through the formation and spread on the upper impermeable boundary of the formation. However, a significant capillary-trapped wake of gas may develop beneath each barrier. Owing to the low solubility of hydrogen in water and assuming relatively slow groundwater flow rates, this trapped hydrogen may require a period of tens to hundreds of thousands of years to dissolve and form a cloud of hydrogen rich water. Although simplified, these models provide a framework to assess the possible travel times and pathways of such a gas plume.

  6. Statistical Change Detection for Diagnosis of Buoyancy Element Defects on Moored Floating Vessels

    DEFF Research Database (Denmark)

    Blanke, Mogens; Fang, Shaoji; Galeazzi, Roberto

    2012-01-01

    . After residual generation, statistical change detection scheme is derived from mathematical models supported by experimental data. To experimentally verify loss of an underwater buoyancy element, an underwater line breaker is designed to create realistic replication of abrupt faults. The paper analyses......Floating platforms with mooring systems are used extensively in off-shore operations. Part of the mooring systems are underwater buoyancy elements that are attached to the mooring lines. Loss or damage of a buoyancy element is invisible but changes the characteristics of the mooring system...

  7. Self-similar evolution of the nonlinear magnetic buoyancy instability

    Science.gov (United States)

    Shibata, K.; Tajima, T.; Matsumoto, R.

    1990-01-01

    A new type of self-similar solution of ideal magnetohydrodynamics (MHD) in the nonlinear stage of the undular model (k parallel to B) of the magnetic buoyancy instability (the ballooning instability in fusion plasma physics or the Parker instability in astrophysics) is found through MHD simulation and theory. The linear theory developed agrees well with the simulation in the early (linear) stage. The nonlinear stages of the instability in the simulation show the self-similar evolution. One of the solutions obtained from the nonlinear analysis has the characteristics of nonlinear instability in Lagrangian coordinates; the fluid velocity and the Alfven speed on each magnetic loop increase exponentially with time, because the loop is evacuated by the field-aligned motion of matter resulting from gravitational acceleration. In the later stage of the nonlinear evolution, the solution property changes from exponential to power-law time dependence. The latter corresponds to a force-free expansion solution. The later saturation of the velocity increment is also discussed.

  8. Capillary and Gas Trapping Controls on Pumice Buoyancy in Water

    Science.gov (United States)

    Fauria, K. E.; Manga, M.; Wei, Z.

    2016-12-01

    Pumice can float on water for months to years. The longevity of pumice floatation is unexpected, however, because pumice pores are highly connected and water wets volcanic glass. As a result, observations of long floating times have not been reconciled with predictions of rapid sinking. We propose a mechanism to resolve this paradox - the trapping of gas bubbles by water within the pumice. Gas trapping refers to the isolation of gas by water within pore throats such that the gas becomes disconnected from the atmosphere and unable to escape. We use X-ray microtomography images of partially saturated pumice to demonstrate that gas trapping occurs in both ambient-temperature and hot (500°C) pumice. Furthermore, we show that the distribution of trapped gas clusters matches percolation theory predictions. Finally, we propose that diffusion out of trapped gaseous bubbles determines pumice floatation time. Experimental measurements of pumice floatation support a diffusion control on pumice buoyancy and we find that floatation time scales like τ L2/(Dθ2) where is the floatation time, L is the characteristic length of the pumice, D is the gas-water diffusion coefficient, and θ is pumice water saturation.

  9. Using surface integrals for checking the Archimedes' law of buoyancy

    CERN Document Server

    Lima, F M S

    2011-01-01

    A mathematical derivation of the force exerted by an \\emph{inhomogeneous} (i.e., compressible) fluid on the surface of an \\emph{arbitrarily-shaped} body immersed in it is not found in literature, which may be attributed to our trust on Archimedes' law of buoyancy. However, this law, also known as Archimedes' principle (AP), does not yield the force observed when the body is in contact to the container walls, as is more evident in the case of a block immersed in a liquid and in contact to the bottom, in which a \\emph{downward} force that \\emph{increases with depth} is observed. In this work, by taking into account the surface integral of the pressure force exerted by a fluid over the surface of a body, the general validity of AP is checked. For a body fully surrounded by a fluid, homogeneous or not, a gradient version of the divergence theorem applies, yielding a volume integral that simplifies to an upward force which agrees to the force predicted by AP, as long as the fluid density is a \\emph{continuous func...

  10. Buoyancy driven acceleration in a hospital operating room indoor environment

    Science.gov (United States)

    McNeill, James; Hertzberg, Jean; Zhai, John

    2011-11-01

    In hospital operating rooms, centrally located non-isothermal ceiling jets provide sterile air for protecting the surgical site from infectious particles in the room air as well as room cooling. Modern operating rooms are requiring larger temperature differences to accommodate increasing cooling loads for heat gains from medical equipment. This trend may lead to significant changes in the room air distribution patterns that may sacrifice the sterile air field across the surgical table. Quantitative flow visualization experiments using laser sheet illumination and RANS modeling of the indoor environment were conducted to demonstrate the impact of the indoor environment thermal conditions on the room air distribution. The angle of the jet shear layer was studied as function of the area of the vena contracta of the jet, which is in turn dependent upon the Archimedes number of the jet. Increases in the buoyancy forces cause greater air velocities in the vicinity of the surgical site increasing the likelihood of deposition of contaminants in the flow field. The outcome of this study shows the Archimedes number should be used as the design parameter for hospital operating room air distribution in order to maintain a proper supply air jet for covering the sterile region. This work is supported by ASHRAE.

  11. Buoyancy Regulation and the Energetics of Diving in Dolphins Seals, Sea Lions and Sea Otters

    National Research Council Canada - National Science Library

    Costa, Daniel

    1998-01-01

    We examined swim speed and ascent descent rates in sea lions and elephant seals in order to make comparisons in their diving strategies and how these may be effected by different strategies of buoyancy regulation...

  12. Buoyancy package for self-contained acoustic doppler current profiler mooring

    Digital Repository Service at National Institute of Oceanography (India)

    Venkatesan, R.; Krishnakumar, V.

    A buoyancy package for self-contained Acoustic Doppler Current Profiler(SC-ADCP 1200 RD instruments USA) was designed and fabricated indigenously, for subsurface mooring in coastal waters. The system design is discussed. The design to keep SC...

  13. Annual and seasonal mean buoyancy fluxes for the tropical Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Prasad, T.G.

    INSAT-derived monthly mean precipitation, combined with estimates of evaporation from COADS, are used to prepare the annual mean and seasonal distributions of evaporation-precipitation (E-P)) and buoyancy fluxes for the tropical Indian Ocean...

  14. Effects of body condition on buoyancy in endangered North Atlantic right whales.

    Science.gov (United States)

    Nousek-McGregor, Anna E; Miller, Carolyn A; Moore, Michael J; Nowacek, Douglas P

    2014-01-01

    Buoyancy is an important consideration for diving marine animals, resulting in specific ecologically relevant adaptations. Marine mammals use blubber as an energy reserve, but because this tissue is also positively buoyant, nutritional demands have the potential to cause considerable variation in buoyancy. North Atlantic right whales Eubalaena glacialis are known to be positively buoyant as a result of their blubber, and the thickness of this layer varies considerably, but the effect of this variation on buoyancy has not been explored. This study compared the duration and rate of ascending and descending glides, recorded with an archival tag, with blubber thickness, measured with an ultrasound device, in free-swimming right whales. Ascending whales with thicker blubber had shorter portions of active propulsion and longer passive glides than whales with thinner blubber, suggesting that blubber thickness influences buoyancy because the buoyant force is acting in the same direction as the animal's movement during this phase. Whales with thinner layers also used similar body angles and velocities when traveling to and from depth, while those with thicker layers used shallower ascent angles but achieved higher ascent velocities. Such alterations in body angle may help to reduce the cost of transport when swimming against the force of buoyancy in a state of augmented positive buoyancy, which represents a dynamic response to reduce the energetic consequences of physiological changes. These results have considerable implications for any diving marine animal during periods of nutritional stress, such as during seasonal migrations and annual variations in prey availability.

  15. Neutral Buoyancy Simultor (NBS) NB-1 Large Mass Transfer simulation

    Science.gov (United States)

    1980-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. And construction methods had to be efficient due to limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. Pictured is a Massachusetts Institute of Technology (MIT) student working in a spacesuit on the Experimental Assembly of Structures in Extravehicular Activity (EASE) project which was developed as a joint effort between MFSC and MIT. The EASE experiment required that crew members assemble small components to form larger components, working from the payload bay of the space shuttle.

  16. Gravitaxis of Euglena gracilis depends only partially on passive buoyancy

    Science.gov (United States)

    Richter, Peter R.; Schuster, Martin; Lebert, Michael; Streb, Christine; Häder, Donat-Peter

    In darkness, the unicellular freshwater flagellate Euglena gracilis shows a pronounced negative gravitactic behavior, and the cells swim actively upward in the water column. Up to now it was unclear whether this behavior is based on a passive (physical) alignment mechanism (e.g., buoyancy due to a fore-aft asymmetry of the cell body) or on an active physiological mechanism. A sounding rocket experiment was performed in which the effect of sub-1g-accelerations (0.05, 0.08, 0.12, and 0.2g) on untreated living cells and immobilized (fixation with liquid nitrogen) cells was observed. By means of computerized image analysis the angles of the cells long axis with respect to the acceleration vector were analyzed in order to calculate and compare the reorientation kinetics of the immobilized cells versus that of the controls. In both groups, the reorientation kinetics depended on the dose, but the reorientation of the living cells was about five times faster than that of the immobilized cells. This indicates that in young cells gravitaxis can be explained by a physical mechanism only to a small extend. In older cultures, in which the cells often have a drop shaped cell body, the physical reorientation is considerably faster, and a more pronounced influence of passive alignment caused by fore/aft asymmetry (drag-gravity model) can not be excluded. In addition to these results, Euglena gracilis cells seem to respond very sensitively to small accelerations when they are applied after a longer microgravity period. The data indicate that gravitactic orientation occurred at an acceleration as low as 0.05g.

  17. Neutral Buoyancy Test - NB-18 - Large Space Structure Assembly

    Science.gov (United States)

    1979-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. Construction methods had to be efficient due to the limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. With the help of the NBS, building a space station became more of a reality. In a joint venture between NASA/Langley Research Center in Hampton, Virginia and the MSFC, the Assembly Concept for Construction of Erectable Space Structures (ACCESS) was developed and demonstrated at MSFC's NBS. The primary objective of this experiment was to test the ACCESS structural assembly concept for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction. Pictured is a demonstration of ACCESS.

  18. Buoyancy-activated cell sorting using targeted biotinylated albumin microbubbles.

    Directory of Open Access Journals (Sweden)

    Yu-Ren Liou

    Full Text Available Cell analysis often requires the isolation of certain cell types. Various isolation methods have been applied to cell sorting, including fluorescence-activated cell sorting and magnetic-activated cell sorting. However, these conventional approaches involve exerting mechanical forces on the cells, thus risking cell damage. In this study we applied a novel isolation method called buoyancy-activated cell sorting, which involves using biotinylated albumin microbubbles (biotin-MBs conjugated with antibodies (i.e., targeted biotin-MBs. Albumin MBs are widely used as contrast agents in ultrasound imaging due to their good biocompatibility and stability. For conjugating antibodies, biotin is conjugated onto the albumin MB shell via covalent bonds and the biotinylated antibodies are conjugated using an avidin-biotin system. The albumin microbubbles had a mean diameter of 2 μm with a polydispersity index of 0.16. For cell separation, the MDA-MB-231 cells are incubated with the targeted biotin-MBs conjugated with anti-CD44 for 10 min, centrifuged at 10 g for 1 min, and then allowed 1 hour at 4 °C for separation. The results indicate that targeted biotin-MBs conjugated with anti-CD44 antibodies can be used to separate MDA-MB-231 breast cancer cells; more than 90% of the cells were collected in the MB layer when the ratio of the MBs to cells was higher than 70:1. Furthermore, we found that the separating efficiency was higher for targeted biotin-MBs than for targeted avidin-incorporated albumin MBs (avidin-MBs, which is the most common way to make targeted albumin MBs. We also demonstrated that the recovery rate of targeted biotin-MBs was up to 88% and the sorting purity was higher than 84% for a a heterogenous cell population containing MDA-MB-231 cells (CD44(+ and MDA-MB-453 cells (CD44-, which are classified as basal-like breast cancer cells and luminal breast cancer cells, respectively. Knowing that the CD44(+ is a commonly used cancer

  19. The argonaut shell: gas-mediated buoyancy control in a pelagic octopus

    Science.gov (United States)

    Finn, Julian K.; Norman, Mark D.

    2010-01-01

    Argonauts (Cephalopoda: Argonautidae) are a group of rarely encountered open-ocean pelagic octopuses with benthic ancestry. Female argonauts inhabit a brittle ‘paper nautilus’ shell, the role of which has puzzled naturalists for millennia. The primary role attributed to the shell has been as a receptacle for egg deposition and brooding. Our observations of wild argonauts have revealed that the thin calcareous shell also functions as a hydrostatic structure, employed by the female argonaut to precisely control buoyancy at varying depths. Female argonauts use the shell to ‘gulp’ a measured volume of air at the sea surface, seal off the captured gas using flanged arms and forcefully dive to a depth where the compressed gas buoyancy counteracts body weight. This process allows the female argonaut to attain neutral buoyancy at depth and potentially adjust buoyancy to counter the increased (and significant) weight of eggs during reproductive periods. Evolution of this air-capture strategy enables this negatively buoyant octopus to survive free of the sea floor. This major shift in life mode from benthic to pelagic shows strong evolutionary parallels with the origins of all cephalopods, which attained gas-mediated buoyancy via the closed-chambered shells of the true nautiluses and their relatives. PMID:20484241

  20. Effect of bioadhesion on initial in vitro buoyancy of effervescent floating matrix tablets of ciprofloxacin HCL

    Directory of Open Access Journals (Sweden)

    Jeetendra Singh Negi

    2011-01-01

    Full Text Available The purpose of this study was to investigate effect of bioadhesion on the initial in vitro buoyancy behaviour of effervescent matrix tablets of ciprofloxacin HCl (CIPRO. Tablets were prepared by direct compression using HPMC K4M and Carbopol 971P as hydrophilic-controlled release polymers, sodium bicarbonate (NaHCO 3 as gas-generating agent, polyplasdone XL, Explotab and Ac-Di-Sol as swelling agents. Tablets were evaluated for normal and modified initial in vitro floating behavior, floating duration, swelling behavior and in vitro drug release studies. A modified buoyancy lag time for tablets was determined in order to include the effect of bioadhesion on initial buoyancy. The initial buoyancy was found depended on bioadhesion ability of tablets. The lowest modified buoyancy lag time of 20 seconds was obtained for Formulation F7 having both NaHCO 3 and polyplasdone XL. The floating duration was also found dependent on concentration of NaHCO 3 and swelling agents. The drug release of F7 was also sustained up to 12-hr duration with anomalous drug transport mechanism.

  1. Effect of bioadhesion on initial in vitro buoyancy of effervescent floating matrix tablets of ciprofloxacin HCL.

    Science.gov (United States)

    Negi, Jeetendra Singh; Trivedi, Abhinav; Khanduri, Praveen; Negi, Vandana; Kasliwal, Nikhil

    2011-04-01

    The purpose of this study was to investigate effect of bioadhesion on the initial in vitro buoyancy behaviour of effervescent matrix tablets of ciprofloxacin HCl (CIPRO). Tablets were prepared by direct compression using HPMC K4M and Carbopol 971P as hydrophilic-controlled release polymers, sodium bicarbonate (NaHCO(3)) as gas-generating agent, polyplasdone XL, Explotab and Ac-Di-Sol as swelling agents. Tablets were evaluated for normal and modified initial in vitro floating behavior, floating duration, swelling behavior and in vitro drug release studies. A modified buoyancy lag time for tablets was determined in order to include the effect of bioadhesion on initial buoyancy. The initial buoyancy was found depended on bioadhesion ability of tablets. The lowest modified buoyancy lag time of 20 seconds was obtained for Formulation F7 having both NaHCO(3) and polyplasdone XL. The floating duration was also found dependent on concentration of NaHCO(3) and swelling agents. The drug release of F7 was also sustained up to 12-hr duration with anomalous drug transport mechanism.

  2. Ceramic Spheres—A Novel Solution to Deep Sea Buoyancy Modules

    Directory of Open Access Journals (Sweden)

    Bo Jiang

    2016-06-01

    Full Text Available Ceramic-based hollow spheres are considered a great driving force for many applications such as offshore buoyancy modules due to their large diameter to wall thickness ratio and uniform wall thickness geometric features. We have developed such thin-walled hollow spheres made of alumina using slip casting and sintering processes. A diameter as large as 50 mm with a wall thickness of 0.5–1.0 mm has been successfully achieved in these spheres. Their material and structural properties were examined by a series of characterization tools. Particularly, the feasibility of these spheres was investigated with respect to its application for deep sea (>3000 m buoyancy modules. These spheres, sintered at 1600 °C and with 1.0 mm of wall thickness, have achieved buoyancy of more than 54%. As the sphere’s wall thickness was reduced (e.g., 0.5 mm, their buoyancy reached 72%. The mechanical performance of such spheres has shown a hydrostatic failure pressure above 150 MPa, corresponding to a rating depth below sea level of 5000 m considering a safety factor of 3. The developed alumina-based ceramic spheres are feasible for low cost and scaled-up production and show great potential at depths greater than those achievable by the current deep-sea buoyancy module technologies.

  3. Buoyancy increase and drag-reduction through a simple superhydrophobic coating.

    Science.gov (United States)

    Hwang, Gi Byoung; Patir, Adnan; Page, Kristopher; Lu, Yao; Allan, Elaine; Parkin, Ivan P

    2017-06-08

    A superhydrophobic paint was fabricated using 1H,1H,2H,2H-perfluorooctyltriethoxysilane (PFOTES), TiO 2 nanoparticles and ethanol. The paint has potential for aquatic application of a superhydrophobic coating as it induces increased buoyancy and drag reduction. Buoyance testing showed that the reduction of surface energy by superhydrophobic coating made it feasible that glass, a high density material, was supported by the surface tension of water. In a miniature boat sailing test, it was shown that the low energy surface treatment decreased the adhesion of water molecules to the surface of the boat resulting in a reduction of the drag force. Additionally, a robust superhydrophobic surface was fabricated through layer-by-layer coating using adhesive double side tape and the paint, and after a 100 cm abrasion test with sand paper, the surface still retained its water repellency, enhanced buoyancy and drag reduction.

  4. Flows and Stratification of an Enclosure Containing Both Localised and Vertically Distributed Sources of Buoyancy

    Science.gov (United States)

    Partridge, Jamie; Linden, Paul

    2013-11-01

    We examine the flows and stratification established in a naturally ventilated enclosure containing both a localised and vertically distributed source of buoyancy. The enclosure is ventilated through upper and lower openings which connect the space to an external ambient. Small scale laboratory experiments were carried out with water as the working medium and buoyancy being driven directly by temperature differences. A point source plume gave localised heating while the distributed source was driven by a controllable heater mat located in the side wall of the enclosure. The transient temperatures, as well as steady state temperature profiles, were recorded and are reported here. The temperature profiles inside the enclosure were found to be dependent on the effective opening area A*, a combination of the upper and lower openings, and the ratio of buoyancy fluxes from the distributed and localised source Ψ =Bw/Bp . Industrial CASE award with ARUP.

  5. Academic Blogging: Academic Practice and Academic Identity

    Science.gov (United States)

    Kirkup, Gill

    2010-01-01

    This paper describes a small-scale study which investigates the role of blogging in professional academic practice in higher education. It draws on interviews with a sample of academics (scholars, researchers and teachers) who have blogs and on the author's own reflections on blogging to investigate the function of blogging in academic practice…

  6. Study of Buoyancy Effects in Diffusion Flames Using Rainbow Schlieren Deflectometry

    Science.gov (United States)

    Agrawal, Ajay K.; Gollahalli, Subramanyam R.; Griffin, DeVon

    1997-01-01

    Diffusion flames are extensively encountered in many domestic and industrial processes. Even after many decades of research, a complete understanding of the diffusion flame structure is not available. The structure and properties of the flames are governed by the mixing (laminar or turbulent), chemical kinetics, radiation and soot processes. Another important phenomenon that affects flame structure in normal gravity is buoyancy. The presence of buoyancy has long hindered the rational understanding of many combustion processes. In gas jet diffusion flames, buoyancy affects the structure of the shear layer, the development of fluid instabilities, and formation of the coherent structures in the near nozzle region of the gas jets. The buoyancy driven instabilities generate vorticial structures outside the flame resulting in flame flicker. The vortices also strongly interact with the small-scale structures in the jet shear layer. This affects the transitional and turbulence characteristics of the flame. For a fundamental understanding of diffusion flames it is essential to isolate the effects of buoyancy. This is the primary goal of the experiments conducted in microgravity. Previous investigations, have shown dramatic differences between the jet flames in microgravity and normal gravity. It has been observed that flames in microgravity are taller and more sooty than in normal gravity. The fuels used in these experiments were primarily hydrocarbons. In the absence of buoyancy the soot resides near the flame region, which adversely affects the entrainment of reactants. It is very important to eliminate the interference of soot on flame characteristics in microgravity. The present work, therefore, focuses on the changes in the flame structure due to buoyancy without the added complexities of heterogeneous reactions. Clean burning hydrogen is used as the fuel to avoid soot formation and minimize radiative losses. Because of the low luminosity of hydrogen flames, we use

  7. Academic Hospitality

    Science.gov (United States)

    Phipps, Alison; Barnett, Ronald

    2007-01-01

    Academic hospitality is a feature of academic life. It takes many forms. It takes material form in the hosting of academics giving papers. It takes epistemological form in the welcome of new ideas. It takes linguistic form in the translation of academic work into other languages, and it takes touristic form through the welcome and generosity with…

  8. Investigating Students' Ideas About Buoyancy and the Influence of Haptic Feedback

    Science.gov (United States)

    Minogue, James; Borland, David

    2016-04-01

    While haptics (simulated touch) represents a potential breakthrough technology for science teaching and learning, there is relatively little research into its differential impact in the context of teaching and learning. This paper describes the testing of a haptically enhanced simulation (HES) for learning about buoyancy. Despite a lifetime of everyday experiences, a scientifically sound explanation of buoyancy remains difficult to construct for many. It requires the integration of domain-specific knowledge regarding density, fluid, force, gravity, mass, weight, and buoyancy. Prior studies suggest that novices often focus on only one dimension of the sinking and floating phenomenon. Our HES was designed to promote the integration of the subconcepts of density and buoyant forces and stresses the relationship between the object itself and the surrounding fluid. The study employed a randomized pretest-posttest control group research design and a suite of measures including an open-ended prompt and objective content questions to provide insights into the influence of haptic feedback on undergraduate students' thinking about buoyancy. A convenience sample (n = 40) was drawn from a university's population of undergraduate elementary education majors. Two groups were formed from haptic feedback (n = 22) and no haptic feedback (n = 18). Through content analysis, discernible differences were seen in the posttest explanations sinking and floating across treatment groups. Learners that experienced the haptic feedback made more frequent use of "haptically grounded" terms (e.g., mass, gravity, buoyant force, pushing), leading us to begin to build a local theory of language-mediated haptic cognition.

  9. Influence of Buoyancy Control Performance on Power Production by the Wave Dragon Nissum Bredning Prototype

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Tedd, James; Friis-Madsen, E.

    2007-01-01

    This paper reports on the real sea performance of the buoyancy control system of Wave Dragon, a floating wave energy converter using the overtopping principle. The device operates with the full independent control system which has been tested during three years of operation. The impact...

  10. Core-annular flow through a horizontal pipe : Hydrodynamic counterbalancing of buoyancy force on core

    NARCIS (Netherlands)

    Ooms, G.; Vuik, C.; Poesio, P.

    2007-01-01

    A theoretical investigation has been made of core-annular flow: the flow of a high-viscosity liquid core surrounded by a low-viscosity liquid annular layer through a horizontal pipe. Special attention is paid to the question of how the buoyancy force on the core, caused by a density difference

  11. Low-buoyancy thermochemical plumes resolve controversy of classical mantle plume concept

    National Research Council Canada - National Science Library

    Dannberg, Juliane; Sobolev, Stephan V

    2015-01-01

    .... We demonstrate that, despite their low buoyancy, large enough thermochemical plumes can rise through the whole mantle causing only negligible surface uplift. Their tails are bulky (>200 km radius) and remain in the upper mantle for 100 millions of years....

  12. Consistent Two-Equation Closure Modelling for Atmospheric Research: Buoyancy and Vegetation Implementations

    DEFF Research Database (Denmark)

    Sogachev, Andrey; Kelly, Mark C.; Leclerc, Monique Y.

    2012-01-01

    A self-consistent two-equation closure treating buoyancy and plant drag effects has been developed, through consideration of the behaviour of the supplementary equation for the length-scale-determining variable in homogeneous turbulent flow. Being consistent with the canonical flow regimes of gri...

  13. Buoyancy effects in vertical rectangular duct with coplanar magnetic field and single sided heat load

    Science.gov (United States)

    Kostichev, P. I.; Poddubnyi, I. I.; Razuvanov, N. G.

    2017-11-01

    In some DEMO blanket designs liquid metal flows in vertical ducts of rectangular cross-section between ceramic breeder units providing their cooling. Heat exchange in these conditions is governed by the influence of magnetic field (coplanar) and by buoyancy effects that depend on the flow orientation to the gravity vector (downward and upward flow). Magnetohydrodynamic and heat transfer of liquid metal in vertical rectangular ducts is not well researched. Experimental study of buoyancy effects in rectangular duct with coplanar magnetic field for one-sided heat load and downward and upward flowsis presented in this paper. The detail research with has been done on mercury MHD close loop with using of the probe technique allow to discover several advantageous and disadvantageous effects. The intensive impact of buoyancy force has been observed in a few regime of downward flow which has been laminarized by magnetic field. Due to the development in the flow of the secondary large-scale vortices heat transfer improved and the temperature fluctuations of the abnormally high intensity have been fixed. On the contrary, in the upward flow the buoyancy force stabilized the flow which lead to decreasing of the turbulence heat transfer ratio and, consequently, deterioration of heat transfer.

  14. Experimental Study of Wind-Opposed Buoyancy-Driven Natural Ventilation

    DEFF Research Database (Denmark)

    Andersen, A.; Bjerre, M.; Chen, Z. D.

    Natural ventilation driven by natural forces, i.e. wind and thermal buoyancy, is an environmentally friendly system for buildings and has been increasingly used around the world in recent years to mitigate the impact on the global environment due to the significant energy consumption by heating...

  15. Teaching Archimedes' Principle to Sixth Graders without Teaching Mass, Density, Pressure, Volume or Buoyancy

    Science.gov (United States)

    Raghavan, Neeraja

    2017-01-01

    Flotation is usually taught in Indian schools after students have been introduced to the concepts of mass, density, pressure, volume and buoyancy. This paper describes an attempt to teach the principle of flotation to a class of sixth graders--who had not yet been taught these concepts--so they could understand (and perhaps, arrive at) Archimedes'…

  16. Teaching Archimedes' Principle to Sixth Graders without Teaching Mass, Density, Pressure, Volume or Buoyancy

    Science.gov (United States)

    Raghavan, Neeraja

    Flotation is usually taught in Indian schools after students have been introduced to the concepts of mass, density, pressure, volume and buoyancy. This paper describes an attempt to teach the principle of flotation to a class of sixth graders--who had not yet been taught these concepts--so they could understand (and perhaps, arrive at) Archimedes'…

  17. Buoyancy-driven flow in a peat moss layer as a mechanism for solute transport

    NARCIS (Netherlands)

    Rappoldt, C.; Pieters, G.J.J.M.; Adema, E.B.; Baaijens, G.J.; Grootjans, A.P.; Duijn, van C.J.

    2003-01-01

    Transport of nutrients, CO2, methane, and oxygen plays an important ecological role at the surface of wetland ecosystems. A possibly important transport mechanism in a water-saturated peat moss layer (usually Sphagnum cuspidatum) is nocturnal buoyancy flow, the downward flow of relatively cold

  18. On the influence of buoyancy and suction/injection In Heat and Mass ...

    African Journals Online (AJOL)

    In this paper, we examined the influence of buoyancy and suction/injection in the problem of unsteady convection with chemical reaction and radiative heat transfer past a flat porous plate moving through a binary mixture in an optically thin environment is presented. The dimensionless governing equations for this ...

  19. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei.

    Science.gov (United States)

    Nakamura, Itsumi; Meyer, Carl G; Sato, Katsufumi

    2015-01-01

    We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei) in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200-300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200-300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes), indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath) or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats.

  20. Unexpected Positive Buoyancy in Deep Sea Sharks, Hexanchus griseus, and a Echinorhinus cookei.

    Directory of Open Access Journals (Sweden)

    Itsumi Nakamura

    Full Text Available We do not expect non air-breathing aquatic animals to exhibit positive buoyancy. Sharks, for example, rely on oil-filled livers instead of gas-filled swim bladders to increase their buoyancy, but are nonetheless ubiquitously regarded as either negatively or neutrally buoyant. Deep-sea sharks have particularly large, oil-filled livers, and are believed to be neutrally buoyant in their natural habitat, but this has never been confirmed. To empirically determine the buoyancy status of two species of deep-sea sharks (bluntnose sixgill sharks, Hexanchus griseus, and a prickly shark, Echinorhinus cookei in their natural habitat, we used accelerometer-magnetometer data loggers to measure their swimming performance. Both species of deep-sea sharks showed similar diel vertical migrations: they swam at depths of 200-300 m at night and deeper than 500 m during the day. Ambient water temperature was around 15°C at 200-300 m but below 7°C at depths greater than 500 m. During vertical movements, all deep-sea sharks showed higher swimming efforts during descent than ascent to maintain a given swimming speed, and were able to glide uphill for extended periods (several minutes, indicating that these deep-sea sharks are in fact positively buoyant in their natural habitats. This positive buoyancy may adaptive for stealthy hunting (i.e. upward gliding to surprise prey from underneath or may facilitate evening upward migrations when muscle temperatures are coolest, and swimming most sluggish, after spending the day in deep, cold water. Positive buoyancy could potentially be widespread in fish conducting daily vertical migration in deep-sea habitats.

  1. Defining Academic--Real or Imagined

    Science.gov (United States)

    Feather, Denis

    2016-01-01

    This paper is part of a study in England that concluded in the latter half of 2009. The study looks at academic identity through the lens of those lecturers delivering higher education business programmes in further education colleges, and their subsequent perceptions and definitions of an academic. The study identified that academic identity is a…

  2. Academics respond

    DEFF Research Database (Denmark)

    Hazel, Spencer

    2015-01-01

    Contribution to the article "Academics respond: Brexit would weaken UK university research and funding", Guardian Witness, The Guardian, UK......Contribution to the article "Academics respond: Brexit would weaken UK university research and funding", Guardian Witness, The Guardian, UK...

  3. Academic Jibberish

    Science.gov (United States)

    Krashen, Stephen

    2012-01-01

    In this article, the author talks about academic jibberish. Alfie Kohn states that a great deal of academic writing is incomprehensible even to others in the same area of scholarship. Academic Jibberish may score points for the writer but does not help research or practice. The author discusses jibberish as a career strategy that impresses those…

  4. The Principles of Buoyancy in Marine Fish Eggs and Their Vertical Distributions across the World Oceans.

    Science.gov (United States)

    Sundby, Svein; Kristiansen, Trond

    2015-01-01

    Buoyancy acting on plankton, i.e. the difference in specific gravity between plankton and the ambient water, is a function of salinity and temperature. From specific gravity measurements of marine fish eggs salinity appears to be the only determinant of the buoyancy indicating that the thermal expansions of the fish egg and the ambient seawater are equal. We analyze the mechanisms behind thermal expansion in fish eggs in order to determine to what extent it can be justified to neglect the effects of temperature on buoyancy. Our results confirm the earlier assumptions that salinity is the basic determinant on buoyancy in marine fish eggs that, in turn, influence the vertical distributions and, consequently, the dispersal of fish eggs from the spawning areas. Fish populations have adapted accordingly by producing egg specific gravities that tune the egg buoyancy to create specific vertical distributions for each local population. A wide variety of buoyancy adaptations are found among fish populations. The ambient physical conditions at the spawning sites form a basic constraint for adaptation. In coastal regions where salinity increases with depth, and where the major fraction of the fish stocks spawns, pelagic and mesopelagic egg distributions dominate. However, in the larger part of worlds' oceans salinity decreases with depth resulting in different egg distributions. Here, the principles of vertical distributions of fish eggs in the world oceans are presented in an overarching framework presenting the basic differences between regions, mainly coastal, where salinity increases with depth and the major part of the world oceans where salinity decreases with depth. We show that under these latter conditions, steady-state vertical distribution of mesopelagic fish eggs cannot exist as it does in most coastal regions. In fact, a critical spawning depth must exist where spawning below this depth threshold results in eggs sinking out of the water column and become lost for

  5. Second-law analysis for buoyancy-driven hydromagnetic couple stress fluid flow through a porous channel

    Science.gov (United States)

    Kareem, Semiu O.; Adesanya, Samuel O.; Vincent, Uchechukwu E.

    2016-08-01

    This paper examines the combined effects of the buoyancy force and of the magnetic field on the entropy generation rate in the flow of a couple stress fluid through a porous vertical channel. The flow's dynamical equations were non-dimensionalised and solved via the application of the Adomian decomposition method (ADM). Variations of some thermo-physical parameters were conducted and discussed, with regard to the physics of the fluid. Our result shows that the entropy generation rate increases as the buoyancy increases in the fluid. In addition, the irreversibility in the flow system results mainly from the fluid's viscosity, ohmic heating, and the buoyancy.

  6. Buoyancy effect on atmospheric surface layer: measurements from the East Coast of Malaysia

    Science.gov (United States)

    Harun, Z.; Reda, E.; Zulkifli, Rozli

    2017-04-01

    The nature and evolution of the atmospheric surface layer is still unresolved completely. Many questions regarding the existence of the z-less layer and trend of the cross correlations still remain open. This research analyzes some of the surface layer ambiguities. In this research temperature, velocity and turbulence data were collected from a weather station facility located in the Marine Ecosystem Research Centre (EKOMAR) Mersing on the East Coast of Malaysia. Two high resolution hotwires were utilized at 3 m and 12 m heights above ground. Both gradient Richardson number and Obukhov stability parameter were calculated. Turbulence spectra were plotted at different stability conditions. The results does not show the existence of the z-less layer at deep stable condition. The buoyancy force, under unstable condition, was found responsible for the increase of vertical correlation factor. The fingerprint of the buoyancy force was detected in the spectra at low frequencies.

  7. Buoyancy Limitation of Filamentous Cyanobacteria under Prolonged Pressure due to the Gas Vesicles Collapse

    Science.gov (United States)

    Abeynayaka, Helayaye Damitha Lakmali; Asaeda, Takashi; Kaneko, Yasuko

    2017-08-01

    Freshwater cyanobacterium Pseudanabaena galeata were cultured in chambers under artificially generated pressures, which correspond to the hydrostatic pressures at deep water. Variations occurred in gas vesicles volume, and buoyancy state of cells under those conditions were analyzed at different time intervals (5 min, 1 day, and 5 days). Variations in gas vesicles morphology of cells were observed by transmission electron microscopy images. Settling velocity ( Vs) of cells which governs the buoyancy was observed with the aid of a modified optical microscope. Moreover, effects of the prolonged pressure on cell ballast composition (protein and polysaccharides) were examined. Elevated pressure conditions reduced the cell ballast and caused a complete disappearance of gas vesicles in Pseudanabaena galeata cells. Hence cyanobacteria cells were not able to float within the study period. Observations and findings of the study indicate the potential application of hydrostatic pressure, which naturally occurred in hypolimnion of lakes, to inhibit the re-suspension of cyanobacteria cells.

  8. Buoyancy Effects on Flow Transition in Hydrogen Gas Jet Diffusion Flames

    Science.gov (United States)

    Albers, Burt W.; Agrawal, Ajay K.; Griffin, DeVon (Technical Monitor)

    2000-01-01

    Experiments were performed in earth-gravity to determine how buoyancy affected transition from laminar to turbulent flow in hydrogen gas jet diffusion flames. The jet exit Froude number characterizing buoyancy in the flame was varied from 1.65 x 10(exp 5) to 1.14 x 10(exp 8) by varying the operating pressure and/or burner inside diameter. Laminar fuel jet was discharged vertically into ambient air flowing through a combustion chamber. Flame characteristics were observed using rainbow schlieren deflectometry, a line-of-site optical diagnostic technique. Results show that the breakpoint length for a given jet exit Reynolds number increased with increasing Froude number. Data suggest that buoyant transitional flames might become laminar in the absence of gravity. The schlieren technique was shown as effective in quantifying the flame characteristics.

  9. Numerical and Experimental Study on Negative Buoyance Induced Vortices in N-Butane Jet Flames

    KAUST Repository

    Xiong, Yuan

    2015-07-26

    Near nozzle flow field in flickering n-butane diffusion jet flames was investigated with a special focus on transient flow patterns of negative buoyance induced vortices. The flow structures were obtained through Mie scattering imaging with seed particles in a fuel stream using continuous-wave (CW) Argon-ion laser. Velocity fields were also quantified with particle mage velocimetry (PIV) system having kHz repetition rate. The results showed that the dynamic motion of negative buoyance induced vortices near the nozzle exit was coupled strongly with a flame flickering instability. Typically during the flame flickering, the negative buoyant vortices oscillated at the flickering frequency. The vortices were distorted by the flickering motion and exhibited complicated transient vortical patterns, such as tilting and stretching. Numerical simulations were also implemented based on an open source C++ package, LaminarSMOKE, for further validations.

  10. CO$_2$ dissolution controlled by buoyancy driven shear dispersion in a background hydrological flow

    CERN Document Server

    Unwin, H Juliette T; Woods, Andrew W

    2015-01-01

    We present an analytical and numerical study of the long-time flow which controls the dissolution of a plume of CO$_2$ following injection into an anticline structure in a deep saline aquifer of finite vertical extent. Over times of tens to thousands of years, some of the CO$_2$ will dissolve into the underlying groundwater to produce a region of relatively dense, CO$_2$ saturated water directly below the plume of CO$_2$. Continued dissolution then requires the supply of CO$_2$ unsaturated aquifer water. This may be provided by a background hydrological flow or buoyancy driven flow caused by the density contrast between the CO$_2$ saturated and unsaturated water in the aquifer. At long times, the interaction of the cross-layer diffusive mixing with the buoyancy, leads to buoyancy driven shear dispersion of the CO$_2$. With a background hydrological flow, the upstream transport of dissolved CO$_2$ by this dispersion becomes balanced by the oncoming hydrological flow so that CO$_2$ rich water can only spread a ...

  11. Schlieren Measurements of Buoyancy Effects on Flow Transition in Low-Density Gas Jets

    Science.gov (United States)

    Pasumarthi, Kasyap S.; Agrawal, Ajay K.

    2005-01-01

    The transition from laminar to turbulent flow in helium jets discharged into air was studied using Rainbow Schlieren Deflectometry technique. In particular, the effects of buoyancy on jet oscillations and flow transition length were considered. Experiments to simulate microgravity were conducted in the 2.2s drop tower at NASA Glenn Research Center. The jet Reynolds numbers varied from 800 to1200 and the jet Richardson numbers ranged between 0.01 and 0.004. Schlieren images revealed substantial variations in the flow structure during the drop. Fast Fourier Transform (FFT) analysis of the data obtained in Earth gravity experiments revealed the existence of a discrete oscillating frequency in the transition region, which matched the frequency in the upstream laminar regime. In microgravity, the transition occurred farther downstream indicating laminarization of the jet in the absence of buoyancy. The amplitude of jet oscillations was reduced by up to an order of magnitude in microgravity. Results suggest that jet oscillations were buoyancy induced and that the brief microgravity period may not be sufficient for the oscillations to completely subside.

  12. Buoyancy effect on the flow pattern and the thermal performance of an array of circular cylinders

    CERN Document Server

    Fornarelli, Francesco; Oresta, Paolo

    2016-01-01

    In this paper we found, by means of numerical simulations, a transition in the oscillatory character of the flow field for a particular combination of buoyancy and spacing in an array of six circular cylinders at a Reynolds number of 100 and Prandtl number of 0.7. The cylinders are iso-thermal and they are aligned with the Earth acceleration (g). According to the array orientation, an aiding or an opposing buoyancy is considered. The effect of natural convection with respect to the forced convection is modulated with the Richardson number, Ri, ranging between -1 and 1. Two values of center to center spacing (s=3.6d - 4d) are considered. The effects of buoyancy and spacing on the flow pattern in the near and far field are described. Several transitions in the flow patterns are found and a parametric analysis of the dependence of the force coefficients and Nusselt number with respect to the Richardson number is reported. For Ri=-1, the change of spacing ratio from 3.6 to 4 induces a transition in the standard d...

  13. On the relative importance of thermal and chemical buoyancy in impact-induced melting on Mars

    Science.gov (United States)

    Ruedas, T.; Breuer, D.

    2017-09-01

    We ran series of 2D numerical mantle convection simulations of the thermochemical evolution of a Mars-like planet. In order to study the importance of compositional buoyancy of melting mantle, the models were set up in pairs of one including all thermal and compositional contributions to buoyancy and one accounting only for the thermal contributions. Single large impacts were introduced as causes of additional strong local anomalies, and their evolution in the framework of the convecting mantle was tracked. They confirm that the additional buoyancy provided by the depletion of melting mantle can establish a global stable stratification of the convecting mantle and throttle crust production. Furthermore, it is essential in the stabilization and preservation of local compositional anomalies directly beneath the lithosphere and offers a possible explanation for the existence of distinct, long-lived reservoirs in the martian mantle. Such anomalies will be detected by gravimetry rather than by seismic or heat flow measurements. The crustal thickness can be locally overestimated by up to 15-22 km if impact-induced density anomalies in the mantle are neglected.

  14. Relationships of Adolescent Self-Esteem to Selected Academic Variables.

    Science.gov (United States)

    Filozof, Eileen M.; Albertin, Helena K.; Jones, Courtney R.; Steme, Sylvia S.; Myers, Leann; McDermott, Robert J.

    1998-01-01

    Investigated whether self-esteem preceded various academic behaviors and beliefs among high school students. Surveys of sociodemographics, educational plans, perceived academic progress, relative academic standing, and school and home self-esteem indicated that student academic performance influenced subsequent school and home self-esteem.…

  15. Academically Resilient Latino Elementary Students Bridging the Achievement Gap

    Science.gov (United States)

    Diamond, Elena; Furlong, Michael J.; Quirk, Matthew

    2016-01-01

    This study investigated associations between school-readiness patterns of Latino students and their subsequent academic achievement. After identifying a subgroup of students with academic risk at kindergarten entry who showed signs of later average or better academic skill development, academic data were gathered to explore how this group of…

  16. Buoyancy under control: underwater locomotor performance in a deep diving seabird suggests respiratory strategies for reducing foraging effort.

    Directory of Open Access Journals (Sweden)

    Timothée R Cook

    Full Text Available BACKGROUND: Because they have air stored in many body compartments, diving seabirds are expected to exhibit efficient behavioural strategies for reducing costs related to buoyancy control. We study the underwater locomotor activity of a deep-diving species from the Cormorant family (Kerguelen shag and report locomotor adjustments to the change of buoyancy with depth. METHODOLOGY/PRINCIPAL FINDINGS: Using accelerometers, we show that during both the descent and ascent phases of dives, shags modelled their acceleration and stroking activity on the natural variation of buoyancy with depth. For example, during the descent phase, birds increased swim speed with depth. But in parallel, and with a decay constant similar to the one in the equation explaining the decrease of buoyancy with depth, they decreased foot-stroke frequency exponentially, a behaviour that enables birds to reduce oxygen consumption. During ascent, birds also reduced locomotor cost by ascending passively. We considered the depth at which they started gliding as a proxy to their depth of neutral buoyancy. This depth increased with maximum dive depth. As an explanation for this, we propose that shags adjust their buoyancy to depth by varying the amount of respiratory air they dive with. CONCLUSIONS/SIGNIFICANCE: Calculations based on known values of stored body oxygen volumes and on deep-diving metabolic rates in avian divers suggest that the variations of volume of respiratory oxygen associated with a respiration mediated buoyancy control only influence aerobic dive duration moderately. Therefore, we propose that an advantage in cormorants--as in other families of diving seabirds--of respiratory air volume adjustment upon diving could be related less to increasing time of submergence, through an increased volume of body oxygen stores, than to reducing the locomotor costs of buoyancy control.

  17. A novel method for calculating and measuring the second-order buoyancy experienced by a magnet immersed in magnetic fluid

    Science.gov (United States)

    Yu, Jun; Hao, Du; Li, Decai

    2018-01-01

    The phenomenon whereby an object whose density is greater than magnetic fluid can be suspended stably in magnetic fluid under the magnetic field is one of the peculiar properties of magnetic fluids. Examples of applications based on the peculiar properties of magnetic fluid are sensors and actuators, dampers, positioning systems and so on. Therefore, the calculation and measurement of magnetic levitation force of magnetic fluid is of vital importance. This paper concerns the peculiar second-order buoyancy experienced by a magnet immersed in magnetic fluid. The expression for calculating the second-order buoyancy was derived, and a novel method for calculating and measuring the second-order buoyancy was proposed based on the expression. The second-order buoyancy was calculated by ANSYS and measured experimentally using the novel method. To verify the novel method, the second-order buoyancy was measured experimentally with a nonmagnetic rod stuck on the top surface of the magnet. The results of calculations and experiments show that the novel method for calculating the second-order buoyancy is correct with high accuracy. In addition, the main causes of error were studied in this paper, including magnetic shielding of magnetic fluid and the movement of magnetic fluid in a nonuniform magnetic field.

  18. Heart Rate Responses to Unaided Orion Side Hatch Egress in the Neutral Buoyancy Laboratory

    Science.gov (United States)

    English, Kirk L.; Hwang Emma Y.; Ryder, Jeffrey W.; Kelly, Cody; Walker, Thomas; Ploutz-Snyder, Lori L.

    2016-01-01

    NASA is developing the Orion capsule as a vehicle for transporting crewmembers to and from the International Space Station (ISS) and for future human space exploration missions. Orion and other commercial vehicles are designed to splash down in the ocean where nominally support personnel will assist crewmembers in egressing the vehicle. However, off-nominal scenarios will require crewmembers to egress the vehicle unaided, deploy survival equipment, and ingress a life raft. PURPOSE: To determine the heart rate (HR) responses to unaided Orion side hatch egress and raft ingress as a part of the NASA Crew Survival Engineering Team's evaluation of the PORT Orion mockup in the Neutral Buoyancy Laboratory (NBL). METHODS: Nineteen test subjects, including four astronauts (N=19, 14 males/5 females, 38.6+/-8.4 y, 174.4+/-9.6 cm, 75.7+/-13.1 kg), completed a graded maximal test on a cycle ergometer to determine VO2peak and HRpeak and were divided into five crews of four members each; one subject served on two crews. Each crew was required to deploy a life raft, egress the Orion vehicle from the side hatch, and ingress the life raft with two 8 kg emergency packs per crew. Each crew performed this activity one to three times; a total of ten full egresses were completed. Subjects wore a suit that was similar in form, mass, and function to the Modified Advanced Crew Escape Suit (MACES) including helmet, gloves, boots, supplemental O2 bottles, and a CO2-inflated life preserver (approx.18 kg); subjects began each trial seated supine in the PORT Orion mockup with seat belts and mockup O2 and communication connections and ended each trial with all four crewmembers inside the life raft. RESULTS: VO2peak was 40.8+/-6.8 mL/kg/min (3.1+/-0.7 L/min); HRpeak was 181+/-10 bpm. Total egress time across trials was 5.0+/-1.6 min (range: 2.8-8.0 min); all subjects were able to successfully complete all trials. Average maximum HR at activity start, at the hatch opening, in the water, and in the

  19. Subsequence Automata with Default Transitions

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Skjoldjensen, Frederik Rye

    2016-01-01

    of states and transitions) of the subsequence automaton is O(nσ) and that this bound is asymptotically optimal. In this paper, we consider subsequence automata with default transitions, that is, special transitions to be taken only if none of the regular transitions match the current character, and which do...... not consume the current character. We show that with default transitions, much smaller subsequence automata are possible, and provide a full trade-off between the size of the automaton and the delay, i.e., the maximum number of consecutive default transitions followed before consuming a character......(nσ) and delay O(1), thus matching the bound for the standard subsequence automaton construction. The key component of our result is a novel hierarchical automata construction of independent interest....

  20. Subsequence automata with default transitions

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li; Skjoldjensen, Frederik Rye

    2017-01-01

    of states and transitions) of the subsequence automaton is O(nσ) and that this bound is asymptotically optimal. In this paper, we consider subsequence automata with default transitions, that is, special transitions to be taken only if none of the regular transitions match the current character, and which do...... not consume the current character. We show that with default transitions, much smaller subsequence automata are possible, and provide a full trade-off between the size of the automaton and the delay, i.e., the maximum number of consecutive default transitions followed before consuming a character......(1), thus matching the bound for the standard subsequence automaton construction. Finally, we generalize the result to multiple strings. The key component of our result is a novel hierarchical automata construction of independent interest....

  1. Academic Allies

    DEFF Research Database (Denmark)

    Byberg, Rebekka Birkebo

    the national associations of European law: Fédération Internationale pour le Droit Européen, the European law journal Common Market Law Review, and the ITL project, carried out at the European University Institute.It carefully documents an alliance between academics and community actors with the aim...... of providing academic support to the constitutional claim, and it argues that the academic discipline of European law was built and developed through a circular attribution of legal ideas, legitimacy, and self-image between the European Court of Justice, the Commission, and academia –most particularly so...

  2. The Solar Vortex: Electric Power Generation using Anchored, Buoyancy-Induced Columnar Vortices

    Science.gov (United States)

    Glezer, Ari

    2015-04-01

    Naturally-occurring, buoyancy-driven columnar vortices (``dust devils'') that are driven by the instability of thermally stratified air layers and sustained by the entrainment of ground- heated air, occur spontaneously in the natural environment with core diameters of 1-50 m and heights up to 1 km. These vortices convert low-grade waste heat in the air layer overlying the warm surface into a solar-induced wind with significant kinetic energy. Unlike dust devil vortices that are typically free to wander laterally, the Solar Vortex (SoV) is deliberately triggered and anchored within a cylindrical domain bounded by an azimuthal array of stationary ground-mounted vertical vanes and sustained by continuous entrainment of the ground-heated air through these vanes. The mechanical energy of the anchored vortex is exploited for power generation by coupling the vortex to a vertical-axis turbine. This simple, low-cost electric power generating unit is competitive in cost, intermittency, and capacity factor with traditional solar power technologies. The considerable kinetic energy of the vortex column cannot be explained by buoyancy alone, and the fundamental mechanisms associated with the formation, evolution, and dynamics of an anchored, buoyancy-driven columnar vortex were investigated experimentally and numerically with specific emphasis on flow manipulation for increasing the available kinetic energy and therefore the generated power. These investigations have also considered the dependence of the vortex scaling and strength on the thermal resources and on the flow enclosure in the laboratory and in the natural environment. Preliminary outdoor tests of a two-meter scale prototype successfully demonstrated the ability to engender and anchor a columnar vortex using only solar radiation and couple the flow to a vertical axis wind turbine. A kilowatt-scale outer door prototype will be tested during the summer of 2015.

  3. Pressure evolution in shallow magma chambers upon buoyancy-driven replenishment

    Science.gov (United States)

    Papale, P.; Montagna, C. P.; Longo, A.

    2017-03-01

    The invasion of active magma chambers by primitive magma of deeper provenance is a frequent occurrence in volcanic systems, and it is commonly associated with pressurization. Chamber replenishment is driven by pressure and buoyancy forces that cause magma ascent towards shallow depths. We examine the end-member case of pure buoyancy-driven (natural) convection in crustal reservoirs deriving from the presence of degassed, dense magma at shallow level, that can originate a gravitational instability. Space-time-dependent numerical simulations of magma dynamics in composite underground systems reveal highly nonlinear pressure evolution dominated by decompression at shallow depths. This counterintuitive result originates from the compressible nature of multiphase magmas and their complex convection and mixing dynamics. Shallow magma chamber decompression on replenishment is favored by large volatile contents of the uprising magma, resulting in large density contrasts among the resident and the incoming components. These results show that the intuitive concept of magma chamber pressurization upon replenishment may not always hold in real situations dominated by buoyancy, and provide new perspectives for the interpretation of geophysical records at active volcanoes.Plain Language SummaryA common process at active volcanoes worldwide is the arrival of magma from depth of tens of kilometers into shallower (depths of some km) reservoirs ("magma chambers"), containing themselves magma that can be different in terms of gas content and composition. We present numerical simulations that describe this process, with particular reference to the Campi Flegrei volcano in Italy. Our results show that, depending on the specific conditions and the gas contents of the two magma types, this process can lead to a decrease in pressure of the shallow chamber. When interpreting ground deformation signals, very often magma rise toward shallow depths is linked to inflation, caused by pressure

  4. Core-annular flow through a horizontal pipe: hydrodynamic counterbalancing of buoyancy force on core

    OpenAIRE

    Ooms, G.; Vuik, C.; Poesio, P.

    2008-01-01

    A theoretical investigation has been made of core-annular flow: the flow of a high-viscosity liquid core surrounded by a low-viscosity liquid annular layer through a horizontal pipe. Special attention is paid to the question of how the buoyancy force on the core, caused by a density difference between the core and the annular layer, is counterbalanced. From earlier studies it is known that at the interface between the annular layer and the core waves are present that move with respect to the ...

  5. Dynamic effects of plate-buoyancy subduction at Manila Trench, South China Sea

    Science.gov (United States)

    Jiang, L.; Zhan, W.; Sun, J.; Li, J.

    2015-12-01

    Bathymetric map of SCS plate shows two subducting buoyancies, the fossil ridge and the oceanic plateau, which are supposed to impact slab segmentation into the north from Taiwan to 18°N, and the south from 17°N to Mindoro. Hypocenter distribution show that slab dip angle turns lower southwards from 45° to 30° in the north segment, and relatively equals ~45° in the south segment at the depth of 100km. Moreover, volcano distribution can be segmented into Miocene WVC, Quaternary EVC in the north and combined SVC in the south (Fig. A). We found that WVC and SVC mostly locate in a parallel belt ~50km apart to Manila trench, however EVC turn father southwards from 50km to 100km (Fig. B). Above characters congruously indicate that SCS plate kept equal dip angle in Miocene; then the north segment shallowed at 18°N and developed northwards in Quaternary, resulting in lower dip angle than the invariant south segment. To check the transformation of slab dip angle from 45° to 30° between 17~18°N, focal mechanism solution nearby 17°N are found 90° in rake and dip angle, strike parallel to the fossil ridge, indicating a slab tear located coincident with the ridge, where is a weak zone of higher heat flow and lower plate coupling ratio than the adjacent zones and slab can be easily tore as an interface for SCS plate segmentation. Subduction of the two buoyancies within SCS plate is supposed as influential dynamic factor: It caused the trench retreat rate reduced, forming a cusp and a flat convex of Manila trench shape; Moreover, the buoyancies resisted subduction, resulting in shear stress heterogeneity of SCS plate, in consequence the fossil ridge as a fragile belt potentially became stress concentration zone that easily tore; Then the buoyant oceanic plateau might lead to shallowing of the northern SCS plate. To examine the hypothesis, dynamic effects of the two subducting buoyancies are being respectively investigated based on numerical models. (Grt. 41376063, 2013

  6. Academic dentistry.

    Science.gov (United States)

    Rushton, Vivian E; Horner, Keith

    2008-07-01

    Since 1988, thirteen dental schools have provided dental undergraduate programmes within the United Kingdom (UK). In 2006, two new dental schools were created supporting dental education in the community. A further new dental school in Scotland will be accepting students in autumn 2008. In the past 25 years, extensive reorganisation of the NHS has resulted in long-term implications for the training of medical and dental academic staff. The number of academic clinicians is below the minimum viable level and external constraints, combined with a lack of suitable applicants, have led to a moratorium on academic recruitment within some Dental Schools. A detailed review of the historical and associated factors which have led to the problems presently besetting academic dentistry are discussed along with the initiatives introduced in the last 10 years to revitalise the speciality. Also, the present and future outlook for academic dentistry in other countries are discussed. Opinion is divided as to the appropriate setting for the training of undergraduate students between those who support community-based dental education and those who believe dental education should remain within research led dental establishments. External factors are moulding an unsatisfactory situation that is proving increasingly unattractive to the potential dental academic and the case for reform is obvious.

  7. A Six-DOF Buoyancy Tank Microgravity Test Bed with Active Drag Compensation

    Science.gov (United States)

    Sun, Chong; Chen, Shiyu; Yuan, Jianping; Zhu, Zhanxia

    2017-10-01

    Ground experiment under microgravity is very essential because it can verify the space enabling technologies before applied in space missions. In this paper, a novel ground experiment system that can provide long duration, large scale and high microgravity level for the six degree of freedom (DOF) spacecraft trajectory tracking is presented. In which, the most gravity of the test body is balanced by the buoyancy, and the small residual gravity is offset by the electromagnetic force. Because the electromagnetic force on the test body can be adjusted in the electromagnetic system, it can significantly simplify the balancing process using the proposed microgravity test bed compared to the neutral buoyance system. Besides, a novel compensation control system based on the active disturbance rejection control (ADRC) method is developed to estimate and compensate the water resistance online, in order to improve the fidelity of the ground experiment. A six-DOF trajectory tracking in the microgravity system is applied to testify the efficiency of the proposed compensation controller, and the experimental simulation results are compared to that obtained using the classic proportional-integral-derivative (PID) method. The simulation results demonstrated that, for the six-DOF motion ground experiment, the microgravity level can reach to 5 × 10-4 g. And, because the water resistance has been estimated and compensated, the performance of the presented controller is much better than the PID controller. The presented ground microgravity system can be applied in on-orbit service and other related technologies in future.

  8. A turbulence spectral model for sound propagation in the atmosphere that incorporates shear and buoyancy forcings

    Science.gov (United States)

    Wilson

    2000-11-01

    A three-dimensional model for turbulent velocity fluctuations in the atmospheric boundary layer is developed and used to calculate scattering of sound. The model, which is based on von Karman's spectrum, incorporates separate contributions from shear- and buoyancy-forced turbulence. New equations are derived from the model that predict the strength and diffraction parameters for scattering of sound as a function of height from the ground and atmospheric conditions. The need is demonstrated for retaining two distinct scattering length scales, one associated with scattering strength and the other with diffraction. These length scales are height dependent and vary substantially with the relative proportions of shear and buoyancy forcing. The turbulence model predicts that for forward-scattered waves the phase variance is much larger than the log-amplitude variance, a behavior borne out by experimental data. A new method for synthesizing random fields, based on empirical orthogonal functions, is developed to accommodate the height dependence of the turbulence model. The method is applied to numerical calculations of scattering into an acoustic shadow zone, yielding good agreement with previous measurements.

  9. Simulation of buoyancy-induced turbulent flow from a hot horizontal jet

    KAUST Repository

    El-Amin, Mohamed

    2014-02-01

    Experimental visualizations and numerical simulations of a horizontal hot water jet entering cold water into a rectangular storage tank are described. Three different temperature differences and their corresponding Reynolds numbers are considered. Both experimental visualization and numerical computations are carried out for the same flow and thermal conditions. The realizable k - ε model is used for modeling the turbulent flow while the buoyancy is modeled using the Boussinesq approximation. Polynomial approximations of the water properties are used to compare with the Boussinesq approximation. Numerical solutions are obtained for unsteady flow while pressure, velocity, temperature and turbulence distributions inside the water tank as well as the Froude number are analyzed. The experimental visualizations are performed at intervals of five seconds for all different cases. The simulated results are compared with the visualized results, and both of them show the stratification phenomena and buoyancy force effects due to temperature difference and density variation. After certain times, depending on the case condition, the flow tends to reach a steady state. © 2014 Publishing House for Journal of Hydrodynamics.

  10. Experimental parameterisation of principal physics in buoyancy variations of marine teleost eggs.

    Directory of Open Access Journals (Sweden)

    Kyung-Mi Jung

    Full Text Available It is generally accepted that the high buoyancy of pelagic marine eggs is due to substantial influx of water across the cell membrane just before ovulation. Here we further develop the theoretical basis by applying laboratory observations of the various components of the fertilized egg in first-principle equations for egg specific gravity (ρ(egg followed by statistical validation. We selected Atlantic cod as a model animal due to the affluent amount of literature on this species, but also undertook additional dedicated experimental works. We found that specific gravity of yolk plus embryo is central in influencing ρ(egg and thereby the buoyancy. However, our established framework documents the effect on ρ(egg of the initial deposition of the heavy chorion material in the gonad prior to spawning. Thereafter, we describe the temporal changes in ρ(egg during incubation: Generally, the eggs showed a slight rise in ρ(egg from fertilization to mid-gastrulation followed by a gradual decrease until full development of main embryonic organs just before hatching. Ontogenetic changes in ρ(egg were significantly associated with volume and mass changes of yolk plus embryo. The initial ρ(egg at fertilization appeared significantly influenced by the chorion volume fraction which is determined by the combination of the final chorion volume of the oocyte and of the degree of swelling (hydrolyzation prior to spawning. The outlined principles and algorithms are universal in nature and should therefore be applicable to fish eggs in general.

  11. A Review of Some Recent Studies on Buoyancy Driven Flows in an Urban Environment

    Directory of Open Access Journals (Sweden)

    Bodhisatta Hajra

    2014-01-01

    Full Text Available This paper reviews some recent studies (after 2000 pertaining to buoyancy driven flows in nature and thier use in reducing air pollution levels in a city (city ventilation. Natural convection flows occur due to the heating and cooling of various urban surfaces (e.g., mountain slopes, leading to upslope and downslope flows. Such flows can have a significant effect on city ventilation which has been the subject of study in the recent times due to increased pollution levels in a city. A major portion of the research reviewed here consists of natural convection flows occurring along mountain slopes, with a few studies devoted to flows along building walls. The studies discussed here primarily include field measurements and computational fluid dynamics (CFD models. This review shows that for densely populated cities with high pollution levels, natural convection flows (mountain slope or building walls can significantly aid the dispersion of pollutants. Additional studies in this area using CFD and water channel measurements can explain the physical processes involved in such flows and help improve CFD modelling. Future research should focus on a complete understanding of the mechanisms of buoyancy flows in nature and developing design guidelines for better planning of cities.

  12. Resistance characteristics of innovative eco-fitness equipment: a water buoyancy muscular machine.

    Science.gov (United States)

    Chen, Wei-Han; Liu, Ya-Chen; Tai, Hsing-Hao; Liu, Chiang

    2018-03-01

    This paper propose innovative eco-fitness equipment-a water buoyancy muscular machine (WBM machine) in which resistance is generated by buoyancy and fluid resistance. The resistance characteristics during resistance adjustment and under isometric, concentric, eccentric and isokinetic conditions were investigated and compared to a conventional machine with metal weight plates. The results indicated that the isometric, concentric and eccentric resistances could be adjusted by varying the water volume; the maximum resistances under isometric, concentric and eccentric conditions were 163.8, 338.5 and 140.9 N, respectively. The isometric resistances at different positions remained constant in both machines; however the isometric resistance was lower for WBM machine when at a position corresponding to a 5% total displacement. The WBM machine has lower resistance under eccentric conditions and higher resistance under concentric conditions. Although the conventional machine has an identical trend, the variation was minor (within 4 N). In the WBM machine, the eccentric resistance was approximately 30-45% of the concentric resistance. Concentric resistances increased with an increase in velocity in both machines; however, the eccentric resistances decreased with an increase in velocity. In summary, the WBM machine, a piece of innovative eco-fitness equipment, has unique resistance characteristics and expansibility.

  13. The use of spirometry to evaluate pulmonary function in olive ridley sea turtles (Lepidochelys olivacea) with positive buoyancy disorders.

    Science.gov (United States)

    Schmitt, Todd L; Munns, Suzanne; Adams, Lance; Hicks, James

    2013-09-01

    This study utilized computed spirometry to compare the pulmonary function of two stranded olive ridley sea turtles (Lepidochelys olivacea) presenting with a positive buoyancy disorder with two healthy captive olive ridley sea turtles held in a large public aquarium. Pulmonary function test (PFT) measurements demonstrated that the metabolic cost of breathing was much greater for animals admitted with positive buoyancy than for the normal sea turtles. Positively buoyant turtles had higher tidal volumes and significantly lower breathing-frequency patterns with significantly higher expiration rates, typical of gasp-type breathing. The resulting higher energetic cost of breathing in the diseased turtles may have a significant impact on their long-term survival. The findings represent a method for clinical respiratory function analysis for an individual animal to assist with diagnosis, therapy, and prognosis. This is the first study, to our knowledge, to evaluate objectively sea turtles presenting with positive buoyancy and respiratory disease using pulmonary function tests.

  14. Expatriate academics

    DEFF Research Database (Denmark)

    Selmer, Jan; Lauring, Jakob

    2011-01-01

    Purpose – The literature on business expatriates has been increasing rapidly, but research on expatriate academics has remained scant, despite the apparent increasing globalisation of the academic world. Therefore, more research is needed on the latter group of expatriates. This paper aims to fill...... some of the gaps. Design/methodology/approach – A questionnaire was directed electronically towards expatriate academics occupying regular positions in science faculty departments in universities in northern Europe. Findings – Results showed that job clarity was the dominating job factor with strong...... relationships with all of the five investigated work outcome variables, work adjustment, work performance, work effectiveness, job satisfaction, and time to proficiency. Job conflict and job freedom had an association with some of the work outcome variables but not with all of them. Neither workload nor job...

  15. Academic dropout or academic success: a model for prediction.

    Science.gov (United States)

    Kegel-Flom, P

    1986-09-01

    Why do some students who qualify for admission to optometry school become academic dropouts while others succeed? This question was addressed in a study which compared the admission records of 21 academic dropouts from three classes at the University of Houston College of Optometry (UHCO) with 269 retained students. Academic dropouts were found to have significantly lower preoptometry grades, lower Optometry College Admission Test (OCAT) scores, attended less competitive (i.e., less selective) undergraduate institutions, scored lower on the California Psychological Inventory (CPI), and were older than retained students. When these differentiating admission variables, excepting age, were applied to a new entering class, prediction of subsequent academic dismissal or serious academic difficulty was highly accurate. However, it was found that such prediction must take into account not only areas of weakness, i.e., academic and psychological factors which place a student at risk, but also areas of strength which give the student an advantage. For all students, regardless of age, sex, or ethnic origin, it was the ratio of "advantage" factors to "risk" factors which gave the most valid prediction of academic success or failure.

  16. Modeling Diffusion and Buoyancy-Driven Convection with Application to Geological CO2 Storage

    KAUST Repository

    Allen, Rebecca

    2015-04-01

    ABSTRACT Modeling Diffusion and Buoyancy-Driven Convection with Application to Geological CO2 Storage Rebecca Allen Geological CO2 storage is an engineering feat that has been undertaken around the world for more than two decades, thus accurate modeling of flow and transport behavior is of practical importance. Diffusive and convective transport are relevant processes for buoyancy-driven convection of CO2 into underlying fluid, a scenario that has received the attention of numerous modeling studies. While most studies focus on Darcy-scale modeling of this scenario, relatively little work exists at the pore-scale. In this work, properties evaluated at the pore-scale are used to investigate the transport behavior modeled at the Darcy-scale. We compute permeability and two different forms of tortuosity, namely hydraulic and diffusive. By generating various pore ge- ometries, we find hydraulic and diffusive tortuosity can be quantitatively different in the same pore geometry by up to a factor of ten. As such, we emphasize that these tortuosities should not be used interchangeably. We find pore geometries that are characterized by anisotropic permeability can also exhibit anisotropic diffusive tortuosity. This finding has important implications for buoyancy-driven convection modeling; when representing the geological formation with an anisotropic permeabil- ity, it is more realistic to also account for an anisotropic diffusivity. By implementing a non-dimensional model that includes both a vertically and horizontally orientated 5 Rayleigh number, we interpret our findings according to the combined effect of the anisotropy from permeability and diffusive tortuosity. In particular, we observe the Rayleigh ratio may either dampen or enhance the diffusing front, and our simulation data is used to express the time of convective onset as a function of the Rayleigh ratio. Also, we implement a lattice Boltzmann model for thermal convective flows, which we treat as an analog for

  17. Resolving the Mantle Heat Transfer Discrepancy by Reassessing Buoyancy Flux Estimates of Upwelling Plumes

    Science.gov (United States)

    Hoggard, Mark; Parnell-Turner, Ross; White, Nicky

    2017-04-01

    The size and relative importance of mantle plumes is a controversial topic within the geodynamics community. Numerical experiments of mantle convection suggest a wide range of possible behaviours, from minor plumelets through to large scale, whole-mantle upwellings. In terms of observations, recent seismic tomographic models have identified many large, broad plume-like features within the lower mantle. In contrast, existing estimates of buoyancy flux calculated from plume swells have suggested that these upwellings transfer a relatively minor amount of material and heat into the uppermost mantle. Here, we revisit these calculations of buoyancy flux using a global map of plume swells based upon new observations of dynamic topography. Usually, plume flux is calculated from the cross-sectional area of a swell multiplied by either plate velocity or spreading rate. A key assumption is that plume head material flows laterally at or below the velocity of the overriding plate. Published results are dominated by contributions from the Pacific Ocean and suggest that a total of ˜ 2 TW of heat is carried by plumes into the uppermost mantle. An alternative approach exploits swell volume scaled by a characteristic decay time, which removes the reliance on plate velocities. The main assumption of this method is that plumes are in quasi-steady state. In this study, we have applied this volumetric approach in a new global analysis. Our results indicate that the Icelandic plume has a buoyancy flux of ˜ 27 ± 4 Mg s-1 and the Hawaiian plume is ˜ 2.9 ± 0.6 Mg s-1. These revised values are consistent with independent geophysical constraints from the North Atlantic Ocean and Hawaii. All magmatic and amagmatic swells have been included, suggesting that the total heat flux carried to the base of the plates is ˜ 10 ± 2 TW. This revised value is a five-fold increase compared with previous estimates and provides an improved match to published predictions of basal heat flux across the

  18. academic libraries

    African Journals Online (AJOL)

    Information Impact: Journal of Information and Knowledge Management

    libraries in general) can now organise their collections in digital formats such as, electronic books, databases, media resources, ..... Consensus report. ASSAf: Pretoria. Blaxter, L., Hughes, C., & Tight, M. (1998). Writing on academic careers. Studies in. Higher Education, 23 (3)281–295. Eysenbach, G. (2006). Citation ...

  19. Academic Cloning.

    Science.gov (United States)

    Sikula, John P.; Sikula, Andrew F.

    1980-01-01

    The authors define "cloning" as an integral feature of all educational systems, citing teaching practices which reward students for closely reproducing the teacher's thoughts and/or behaviors and administrative systems which tend to promote like-minded subordinates. They insist, however, that "academic cloning" is not a totally…

  20. ACADEMIC TRAINING

    CERN Multimedia

    Françoise Benz

    2002-01-01

    12, 13, 14, March LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 POSTPONED! - Modern Project Management Methods - POSTPONED! By G. Vallet / Ed. Highware, Paris, F. Academic Training Françoise Benz Secretariat Tel. 73127 francoise.benz@cern.ch

  1. Academic Freedom.

    Science.gov (United States)

    Tobin, Brian G.

    The strength of academic freedom has always depended upon historical circumstances. In the United States, higher education began with institutions founded and controlled by religious sects. The notion of who gets educated and to what ends expanded as American democracy expanded. By the 1980's, legitimate calls for equality became a general…

  2. Academic Aspirations

    Science.gov (United States)

    Durant, Linda

    2013-01-01

    As colleges and universities become even more complex organizations, advancement professionals need to have the skills, experience, and academic credentials to succeed in this ever-changing environment. Advancement leaders need competencies that extend beyond fundraising, alumni relations, and communications and marketing. The author encourages…

  3. Effects of buoyancy-driven convection on nucleation and growth of protein crystals.

    Science.gov (United States)

    Nanev, Christo N; Penkova, Anita; Chayen, Naomi

    2004-11-01

    Protein crystallization has been studied in presence or absence of buoyancy-driven convection. Gravity-driven flow was created, or suppressed, in protein solutions by means of vertically directed density gradients that were caused by generating suitable temperature gradients. The presence of enhanced mixing was demonstrated directly by experiments with crustacyanin, a blue-colored protein, and other materials. Combined with the vertical tube position the enhanced convection has two main effects. First, it reduces the number of nucleated hen-egg-white lysozyme (HEWL) crystals, as compared with those in a horizontal capillary. By enabling better nutrition from the protein in the solution, convection results in growth of fewer larger HEWL crystals. Second, we observe that due to convection, trypsin crystals grow faster. Suppression of convection, achieved by decreasing solution density upward in the capillary, can to some extent mimic conditions of growth in microgravity. Thus, impurity supply, which may have a detrimental effect on crystal quality, was avoided.

  4. Buoyancy driven flow in a hot water tank due to standby heat loss

    DEFF Research Database (Denmark)

    Fan, Jianhua; Furbo, Simon

    2012-01-01

    Results of experimental and numerical investigations of thermal behavior in a vertical cylindrical hot water tank due to standby heat loss of the tank are presented. The effect of standby heat loss on temperature distribution in the tank is investigated experimentally on a slim 150l tank...... show that the CFD model predicts satisfactorily water temperatures at different levels of the tank during cooling by standby heat loss. It is elucidated how the downward buoyancy driven flow along the tank wall is established by the heat loss from the tank sides and how the natural convection flow...... with a height to diameter ratio of 5. A tank with uniform temperatures and with thermal stratification is studied. A detailed computational fluid dynamics (CFD) model of the tank is developed to calculate the natural convection flow in the tank. The distribution of the heat loss coefficient for the different...

  5. Solving problems to learn concepts, how does it happen? A case for buoyancy

    Science.gov (United States)

    Buteler, Laura; Coleoni, Enrique

    2016-12-01

    Problem solving is a preferred activity teachers choose to help students learn concepts. At the same time, successful problem solving is widely regarded as a very good indicator of conceptual learning. Many studies have provided evidence that problem solving often improves students' chances of learning concepts. Still, the question remains relatively unexplored as to how this activity is useful to promote concept learning. In this study we explore this question in the setting of three university students solving a problem on hydrostatics, in which the concept of buoyancy is involved. We use coordination class theory to study how these students progress on their conceptual understanding. We were able to describe how this progress is related to contextual traits, as well as to students' particular epistemic stances. Finally, we discuss some implications for research and for teaching.

  6. Modeling the Effects of Buoyancy on the Evolution of Geophysical Boundary Layers

    Science.gov (United States)

    Baum, Eric; Caponi, Enrique A.

    1992-10-01

    A simple modeling based on the Imperial College k-ɛ turbulence description is shown to be capable of describing the highly anisotropic phenomena associated with the strong buoyancy effects encountered in upper ocean (and atmospheric boundary layer) environments. Both diurnal stratification and transition to buoyant mixing (from that driven by wind shear) are described in considerable detail, provided that the modeling of the turbulent Prandtl number and of the buoyant generation term in the ɛ model equation are evaluated in a suitably realistic and consistent way. The resulting model equations are suitable for simulating the evolution of the ensemble-averaged properties of the oceanic mixed layer in response to a specified history of interfacial shear stress and heat flux. The model is tested by comparing the predicted mixed layer evolution with the dissipation rate measurements of Shay and Gregg.

  7. Buoyancy effects on thermal behavior of a flat-plate solar collector

    DEFF Research Database (Denmark)

    Fan, Jianhua; Furbo, Simon

    2008-01-01

    Theoretical and experimental investigations of the flow and temperature distribution in a 12.53 m(2) solar collector panel with an absorber consisting of two vertical manifolds interconnected by 16 parallel horizontal fins have been carried out. The investigations are focused on overheating...... and the influence of the buoyancy effects are considered in the investigations. Further experimental investigations of the solar collector panel are carried out. The flow distribution through the absorber is evaluated by means of temperature measurements on the back of the absorber tubes. The measured temperatures....... The CFD calculations elucidate the flow and temperature distribution in the collector panels of different designs. Based on the investigations, recommendations are given in order to avoid overheating or boiling problems in the solar collector panel....

  8. Velocity intermittency in a buoyancy subrange in a two-dimensional soap film convection experiment.

    Science.gov (United States)

    Zhang, Jie; Wu, X L

    2005-06-17

    In a two-dimensional soap film convection experiment, the velocity fields are found to be strongly intermittent in the buoyancy subrange, which was reported to be nonintermittent in a recent numerical simulation. The structure functions Sq(l)(= ) exhibit self-similar structures and can be described by power laws l(zetaq) for integers 8 > or = q < or = 1. By extending Kolmogorov's refined similarity hypothesis to our system, an analytical form is derived for the scaling exponent zeta(q) = q/2 + (mu/18)(3q - q2). Our measurements yield mu = 0.42, which is significantly greater than 0.2 found in high Reynolds number turbulence in wind tunnels.

  9. Numerical Simulation of Buoyancy-driven Bubble Motion Using Level Set Method

    Science.gov (United States)

    Salih, A.; Ghosh Moulic, S.

    2010-06-01

    This paper discusses the numerical simulation of buoyancy-driven bubbles in various shape regimes using level set method. The effects of both inertia and viscous forces are considered in the mathematical model. Surface tension force at the fluid interface is implemented through the CSF model of Brackbill et al. [2]. The incompressible Navier-Stokes equations were solved on a finite volume based staggered grid using an explicit projection method. Although the level set method offers an elegant way of computing multiphase flows, it is often plagued by mass conservation problems. In the present work, the level set method is augmented with a volume-reinitialization scheme, which helps preserve the individual fluid masses within gas and liquid phases. This enabled us to compute the motion of bubbles in all important shape regimes on a relatively coarse grid.

  10. The Mediational Effect of Academic Self-Discipline (ASD) between Academic Self-Efficacy (ASE) and College GPA

    Science.gov (United States)

    Jung, Kyoung Rae

    2013-01-01

    Drawing upon self-efficacy theory (Bandura, 1997), the purpose of this study was to examine academic self-discipline (ASD) as a mediator of the relationship between academic self-efficacy (ASE) and college GPA, as well as the feedback effect of previous academic performance on subsequent ASE and ASD. To test this research question, I used…

  11. Influence of rheology on buoyancy driven instabilities of miscible displacements in 2D micromodels

    Energy Technology Data Exchange (ETDEWEB)

    D' Angelo, M V; Rosen, M [University Buenos Aires, CONICET. Grupo de Medios Porosos, Facultad de IngenierIa, Paseo Colon 850, 1063 Buenos-Aires (Argentina); Auradou, H; Hulin, J P, E-mail: vdangelo@fi.uba.a, E-mail: auradou@fast.u-psud.f [University Pierre et Marie Curie-Paris 6, University Paris-Sud, CNRS. Lab. FAST, Bat 502, Campus Universitaire, F-91405 Orsay (France)

    2009-05-01

    The stability of miscible displacements of Newtonian and shear-thinning fluids of slightly different densities (DELTArho/rho approx 3x 10{sup -4}) with a mean flow velocity U is investigated in a 2D transparent network of channels (average width = 0.33 mm). Concentration maps providing information at both the global and local scale are obtained through optical absorption measurements and compared in gravitationally stable and unstable vertical flow configurations; the influence of buoyant flows of typical velocity U{sub g} is characterized by the gravity number N{sub g} = U{sub g}/|U|. For N{sub g} < 0.2, the spreading of the mean relative concentration profile is diffusive for both types of rheologies and characterized by a single dispersivity value l{sub d} = D/U. For the Newtonian water-glycerol solution, l{sub d} is only the same in the stable and unstable configurations for |N{sub g}| < 0.01. For 0.01 < N{sub g} < 0.2, l{sub d} is increased by buoyancy in the unstable configuration and increasingly large front structures are observed on the concentration maps; for N{sub g} > 0.2, front spreading is not diffusive any more. In the stable configuration, in contrast, the front is flattened by buoyancy for N{sub g} < -0.01 and l{sub d} reaches values of the order of the length of individual channels. For the shear thinning water-polymer solution, both the concentration maps and the value of l{sub d} are the same in the stable and unstable configurations over the full range of U values investigated: this stabilization is explained by their high effective viscosity at low shear rates keeping N{sub g} below the instability threshold even at the lowest velocities.

  12. Predicting the buoyancy, equilibrium and potential swimming ability of giraffes by computational analysis.

    Science.gov (United States)

    Henderson, Donald M; Naish, Darren

    2010-07-21

    Giraffes (Giraffa camelopardalis) are often stated to be unable to swim, and while few observations supporting this have ever been offered, we sought to test the hypothesis that giraffes exhibited a body shape or density unsuited for locomotion in water. We assessed the floating capability of giraffes by simulating their buoyancy with a three-dimensional mathematical/computational model. A similar model of a horse (Equus caballus) was used as a control, and its floating behaviour replicates the observed orientations of immersed horses. The floating giraffe model has its neck sub-horizontal, and the animal would struggle to keep its head clear of the water surface. Using an isometrically scaled-down giraffe model with a total mass equal to that of the horse, the giraffe's proportionally larger limbs have much higher rotational inertias than do those of horses, and their wetted surface areas are 13.5% greater relative to that of the horse, thus making rapid swimming motions more strenuous. The mean density of the giraffe model (960 gm/l) is also higher than that of the horse (930 gm/l), and closer to that causing negative buoyancy (1000 gm/l). A swimming giraffe - forced into a posture where the neck is sub-horizontal and with a thorax that is pulled downwards by the large fore limbs - would not be able to move the neck and limbs synchronously as giraffes do when moving on land, possibly further hampering the animal's ability to move its limbs effectively underwater. We found that a full-sized, adult giraffe will become buoyant in water deeper than 2.8m. While it is not impossible for giraffes to swim, we speculate that they would perform poorly compared to other mammals and are hence likely to avoid swimming if possible. (c) 2010. Published by Elsevier Ltd. All rights reserved.

  13. Effect of buoyancy on the motion of long bubbles in horizontal tubes

    Science.gov (United States)

    Atasi, Omer; Khodaparast, Sepideh; Scheid, Benoit; Stone, Howard A.

    2017-09-01

    As a confined long bubble translates along a horizontal liquid-filled tube, a thin film of liquid is formed on the tube wall. For negligible inertial and buoyancy effects, respectively, small Reynolds (Re) and Bond (Bo) numbers, the thickness of the liquid film depends only on the flow capillary number (Ca). However, buoyancy effects are no longer negligible as the diameter of the tube reaches millimeter length scales, which corresponds to finite values of Bo. We perform experiments and theoretical analysis for a long bubble in a horizontal tube to investigate the effect of Bond number (0.05 theory for the film thickness at the front of the bubble in a two-dimensional geometry at low capillary numbers Ca<10-3 and finite Bo to account for the effect of larger Ca. The resulting model shows very good agreement with the present experimental measurements. (ii) Due to the asymmetry in the liquid film thickness and the consequent drainage of the liquid from the top to the bottom of the tube, the bubble is inclined relative to the channel centerline and our side-view visualizations allow direct quantification of the inclination angle, which increases with both Bo and Ca. While the inclination angle at the top is smaller than that at the bottom of the tube, the average of these two values follows the predictions of a mass balance analysis in the central region of the bubble. (iii) The inclination of the bubble causes the thickness of the thin film at the back of the bubble to depend on the length of the bubble, whereas the thickness at the front of the bubble does not depend on the bubble length.

  14. A Closer Look at Boundary Layer Inversion in Large-Eddy Simulations and Bulk Models: Buoyancy-Driven Case

    NARCIS (Netherlands)

    Gentine, P.; Ballon, Gilles; Heerwaarden, van C.C.

    2015-01-01

    The inversion layer (IL) of a clear-sky, buoyancy-driven convective boundary layer is investigated using large-eddy simulations covering a wide range of convective Richardson numbers. A new model of the IL is suggested and tested. The model performs better than previous first-order models of the

  15. Experimental aspects of buoyancy correction in measuring reliable high-pressure excess adsorption isotherms using the gravimetric method

    Science.gov (United States)

    Nguyen, Huong Giang T.; Horn, Jarod C.; Thommes, Matthias; van Zee, Roger D.; Espinal, Laura

    2017-12-01

    Addressing reproducibility issues in adsorption measurements is critical to accelerating the path to discovery of new industrial adsorbents and to understanding adsorption processes. A National Institute of Standards and Technology Reference Material, RM 8852 (ammonium ZSM-5 zeolite), and two gravimetric instruments with asymmetric two-beam balances were used to measure high-pressure adsorption isotherms. This work demonstrates how common approaches to buoyancy correction, a key factor in obtaining the mass change due to surface excess gas uptake from the apparent mass change, can impact the adsorption isotherm data. Three different approaches to buoyancy correction were investigated and applied to the subcritical CO2 and supercritical N2 adsorption isotherms at 293 K. It was observed that measuring a collective volume for all balance components for the buoyancy correction (helium method) introduces an inherent bias in temperature partition when there is a temperature gradient (i.e. analysis temperature is not equal to instrument air bath temperature). We demonstrate that a blank subtraction is effective in mitigating the biases associated with temperature partitioning, instrument calibration, and the determined volumes of the balance components. In general, the manual and subtraction methods allow for better treatment of the temperature gradient during buoyancy correction. From the study, best practices specific to asymmetric two-beam balances and more general recommendations for measuring isotherms far from critical temperatures using gravimetric instruments are offered.

  16. Academic Practice

    DEFF Research Database (Denmark)

    Nielsen, Sandro; Heine, Carmen

    Vejledning i at undgå plagiering ved at følge de normer, der gælder for good academic practice. Dette indebærer at man angiver kilder korrekt, og når det er nødvendigt, og at man har en korrekt udformet fortegnelse over referencer. Vejledningen indeholder konkrete eksempler på korrekt kildeangive......Vejledning i at undgå plagiering ved at følge de normer, der gælder for good academic practice. Dette indebærer at man angiver kilder korrekt, og når det er nødvendigt, og at man har en korrekt udformet fortegnelse over referencer. Vejledningen indeholder konkrete eksempler på korrekt...

  17. Language experience changes subsequent learning.

    Science.gov (United States)

    Onnis, Luca; Thiessen, Erik

    2013-02-01

    What are the effects of experience on subsequent learning? We explored the effects of language-specific word order knowledge on the acquisition of sequential conditional information. Korean and English adults were engaged in a sequence learning task involving three different sets of stimuli: auditory linguistic (nonsense syllables), visual non-linguistic (nonsense shapes), and auditory non-linguistic (pure tones). The forward and backward probabilities between adjacent elements generated two equally probable and orthogonal perceptual parses of the elements, such that any significant preference at test must be due to either general cognitive biases, or prior language-induced biases. We found that language modulated parsing preferences with the linguistic stimuli only. Intriguingly, these preferences are congruent with the dominant word order patterns of each language, as corroborated by corpus analyses, and are driven by probabilistic preferences. Furthermore, although the Korean individuals had received extensive formal explicit training in English and lived in an English-speaking environment, they exhibited statistical learning biases congruent with their native language. Our findings suggest that mechanisms of statistical sequential learning are implicated in language across the lifespan, and experience with language may affect cognitive processes and later learning. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Language experience changes subsequent learning

    Science.gov (United States)

    Onnis, Luca; Thiessen, Erik

    2013-01-01

    What are the effects of experience on subsequent learning? We explored the effects of language-specific word order knowledge on the acquisition of sequential conditional information. Korean and English adults were engaged in a sequence learning task involving three different sets of stimuli: auditory linguistic (nonsense syllables), visual non-linguistic (nonsense shapes), and auditory non-linguistic (pure tones). The forward and backward probabilities between adjacent elements generated two equally probable and orthogonal perceptual parses of the elements, such that any significant preference at test must be due to either general cognitive biases, or prior language-induced biases. We found that language modulated parsing preferences with the linguistic stimuli only. Intriguingly, these preferences are congruent with the dominant word order patterns of each language, as corroborated by corpus analyses, and are driven by probabilistic preferences. Furthermore, although the Korean individuals had received extensive formal explicit training in English and lived in an English-speaking environment, they exhibited statistical learning biases congruent with their native language. Our findings suggest that mechanisms of statistical sequential learning are implicated in language across the lifespan, and experience with language may affect cognitive processes and later learning. PMID:23200510

  19. Penguin lungs and air sacs: implications for baroprotection, oxygen stores and buoyancy.

    Science.gov (United States)

    Ponganis, P J; St Leger, J; Scadeng, M

    2015-03-01

    The anatomy and volume of the penguin respiratory system contribute significantly to pulmonary baroprotection, the body O2 store, buoyancy and hence the overall diving physiology of penguins. Therefore, three-dimensional reconstructions from computerized tomographic (CT) scans of live penguins were utilized to measure lung volumes, air sac volumes, tracheobronchial volumes and total body volumes at different inflation pressures in three species with different dive capacities [Adélie (Pygoscelis adeliae), king (Aptenodytes patagonicus) and emperor (A. forsteri) penguins]. Lung volumes scaled to body mass according to published avian allometrics. Air sac volumes at 30 cm H2O (2.94 kPa) inflation pressure, the assumed maximum volume possible prior to deep dives, were two to three times allometric air sac predictions and also two to three times previously determined end-of-dive total air volumes. Although it is unknown whether penguins inhale to such high volumes prior to dives, these values were supported by (a) body density/buoyancy calculations, (b) prior air volume measurements in free-diving ducks and (c) previous suggestions that penguins may exhale air prior to the final portions of deep dives. Based upon air capillary volumes, parabronchial volumes and tracheobronchial volumes estimated from the measured lung/airway volumes and the only available morphometry study of a penguin lung, the presumed maximum air sac volumes resulted in air sac volume to air capillary/parabronchial/tracheobronchial volume ratios that were not large enough to prevent barotrauma to the non-collapsing, rigid air capillaries during the deepest dives of all three species, and during many routine dives of king and emperor penguins. We conclude that volume reduction of airways and lung air spaces, via compression, constriction or blood engorgement, must occur to provide pulmonary baroprotection at depth. It is also possible that relative air capillary and parabronchial volumes are

  20. Importance of initial buoyancy field on evolution of mantle thermal structure: Implications of surface boundary conditions

    Directory of Open Access Journals (Sweden)

    Petar Glišović

    2015-01-01

    Full Text Available Although there has been significant progress in the seismic imaging of mantle heterogeneity, the outstanding issue that remains to be resolved is the unknown distribution of mantle temperature anomalies in the distant geological past that give rise to the present-day anomalies inferred by global tomography models. To address this question, we present 3-D convection models in compressible and self-gravitating mantle initialised by different hypothetical temperature patterns. A notable feature of our forward convection modelling is the use of self-consistent coupling of the motion of surface tectonic plates to the underlying mantle flow, without imposing prescribed surface velocities (i.e., plate-like boundary condition. As an approximation for the surface mechanical conditions before plate tectonics began to operate we employ the no-slip (rigid boundary condition. A rigid boundary condition demonstrates that the initial thermally-dominated structure is preserved, and its geographical location is fixed during the evolution of mantle flow. Considering the impact of different assumed surface boundary conditions (rigid and plate-like on the evolution of thermal heterogeneity in the mantle we suggest that the intrinsic buoyancy of seven superplumes is most-likely resolved in the tomographic images of present-day mantle thermal structure. Our convection simulations with a plate-like boundary condition reveal that the evolution of an initial cold anomaly beneath the Java-Indonesian trench system yields a long-term, stable pattern of thermal heterogeneity in the lowermost mantle that resembles the present-day Large Low Shear Velocity Provinces (LLSVPs, especially below the Pacific. The evolution of subduction zones may be, however, influenced by the mantle-wide flow driven by deeply-rooted and long-lived superplumes since Archean times. These convection models also detect the intrinsic buoyancy of the Perm Anomaly that has been identified as a unique

  1. SIMULATION OF FREE CURRENT FLOWS IN BUOYANCY-DRIVEN VENTILATION SYSTEMS

    Directory of Open Access Journals (Sweden)

    D. V. Abramkina

    2017-01-01

    Full Text Available Objectives. The aim of the study is to analyse the effect of the design and methods for heating the ventilation duct of a buoyancy- driven system on the formation of free convective air currents in it.Methods. The study of free convection under the conditions of interior problem was carried out using the CFD software, based on  the finite volume method with unstructured grid. Ansys Fluent software was used as a calculation tool in the study, due to its having a high convergence of numerical solutions offering full-scale  measurements of convective currents.To evaluate the reliability of  the results obtained, a validation procedure was carried out, allowing us to determine how accurately the selected conceptual model describes the investigated flow through a comparison of experimental and numerical data.Results. The results of numerical modelling of free convective currents occurring in the heated channel of the ventilation system of  the top floor of a multi-storey residential building are presented in  the article. In the course of the study, the air velocity at the entrance to the ventilation duct was found to depend on the calculated  temperature difference θ ˚C for various heating methods. A gradual  increase in the discrepancy between the numerical simulation and  experimental results is observed if the calculated temperature  difference > 20 ° C. This phenomenon is due to the fact that with  increased duct temperature, it is quite difficult to achieve even  heating under actual conditions; this is especially noticeable when  considering the variant when the vertical part of the vent duct and the take-off are both heated. The maximum deviation of the  results is 4.4%. The obtained velocity profiles in the calculated  sections indicate the impact of the ventilation take-off on the nature  of the air flow motion.Conclusion. One of the drawbacks of the existing systems of natural ventilation of residential

  2. ACADEMIC TRAINING

    CERN Multimedia

    Françoise Benz

    2002-01-01

    6, 7 May LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 Decoding the Human Genome, Scientific basis and ethic and social aspects by S.E. Antonarakis and A. Mauron / Univ. of Geneva Decoding the Human genome is a very up-to-date topic, raising several questions besides purely scientific, in view of the two competing teams (public and private), the ethics of using the results, and the fact that the project went apparently faster and easier than expected. The lecture series will address the following chapters: Scientific basis and challenges, Ethical and social aspects of genomics. Academic Training Françoise Benz Tel. 73127

  3. Peer acceptance/rejection and academic achievement

    Directory of Open Access Journals (Sweden)

    Spasenović Vera Z.

    2003-01-01

    Full Text Available Considerations of the nature and role of peer relations in child development indicate that peer interaction is an important factor in developing social and cognitive competences. Peer relations not only influence current but also subsequent academic, behavioral and emotional development. Accepted students more often display better academic achievement, whereas the status of rejection is coupled with academic difficulties and lower academic achievement. Peer rejection is a relatively stable characteristic that can be used to predict difficulties in the years to come, such as repeat of a grade, early drop out, unjustified absences, adaptability problems etc. It is considered that correlation between academic achievement and peer group status is mediated by student social behavior at school. The quality of peer relations and academic achievement are mutually influential i.e. peer acceptance serves as a social resource that facilitates academic achievement, but academic achievement has effects on student acceptance. To help students who display difficulties in social relations, various intervention programs have been well thought of so as to contribute to interpersonal efficiency promotion. Concerning interdependence of social behavior, peer status and academic achievement, it is reasonable to expect that positive changes in behavior, frequently leading to the change of rejection status, will produce, directly or indirectly, positive effects on academic achievement too.

  4. Service Innovation In Academic Libraries

    DEFF Research Database (Denmark)

    Scupola, Ada

    2010-01-01

    Purpose: The purpose of this article is to investigate whether management and employees in academic libraries involve users in library service innovations and what are these user roles. Design/methodology/approach: The paper first conducts a literature review focusing on innovation, new product...... development, new service development and library science with specific focus on users and management. Subsequently the research uses a case study approach to investigate management and customer involvement in a Danish academic library. Findings: Results from the case study show that academic libraries...... are making some attempts to draw on customers in service innovations and not only rely on management and employees. The main conclusion is that there are unexplored possibilities for customer involvement in library service innovations.Research limitations/implications: One limitation relates...

  5. Magma buoyancy and volatile ascent driving autocyclic eruptivity at Hekla Volcano (Iceland)

    Science.gov (United States)

    Hautmann, Stefanie; Sacks, I. Selwyn; Linde, Alan T.; Roberts, Matthew J.

    2017-09-01

    Volcanic eruptions are typically accompanied by ground deflation due to the withdrawal of magma from depth and its effusion at the surface. Here, based on continuous high-resolution borehole strain data, we show that ground deformation was absent during the major effusion phases of the 1991 and 2000 eruptions of Hekla Volcano, Iceland. This lack of surface deformation challenges the classic model of magma intrusion/withdrawal as source for volcanic ground uplift/subsidence. We incorporate geodetic and geochemical observables into theoretical models of magma chamber dynamics in order to constrain quantitatively alternative co- and intereruptive physical mechanisms that govern magma propagation and system pressurization. We find the lack of surface deformation during lava effusion to be linked to chamber replenishment from below whilst magma migrates as a buoyancy-driven flow from the magma chamber towards the surface. We further demonstrate that intereruptive pressure build-up is likely to be generated by volatile ascent within the chamber rather than magma injection. Our model explains the persistent periodic eruptivity at Hekla throughout historic times with self-initiating cycles and is conceptually relevant to other volcanic systems.

  6. Wall effects on the cross-buoyancy around a square cylinder in the steady regime

    Directory of Open Access Journals (Sweden)

    A. K. Dhiman

    2012-06-01

    Full Text Available The effects of blockage ratio on the combined free and forced convection from a long heated square obstacle confined in a horizontal channel are investigated in this work. The numerical computations are performed in the steady regime for Reynolds number = 1 - 30, Richardson number = 0 - 1 for blockage ratios of 0.125 and 0.25 for the fixed Prandtl number of 0.7 (air. The governing equations, along with appropriate boundary conditions, are solved by using a semi-explicit finite volume method implemented on the collocated grid arrangement. The total drag and lift coefficients, local and average Nusselt numbers and the representative streamline, vorticity and isotherm patterns are presented to elucidate the role of blockage ratio on the cross-buoyancy across a confined square cylinder. The asymmetry in the flow and temperature fields decreases with increasing value of the blockage ratio. Similar to forced convection, the total drag coefficient increases with increasing value of the blockage ratio for the fixed values of the Reynolds and Richardson numbers.

  7. A modified emulsion gelation technique to improve buoyancy of hydrogel tablets for floating drug delivery systems.

    Science.gov (United States)

    Yom-Tov, Ortal; Seliktar, Dror; Bianco-Peled, Havazelet

    2015-10-01

    The use of buoyant or floating hydrogel tablets is of particular interest in the sustained release of drugs to the stomach. They have an ability to slow the release rates of drugs by prolonging their absorption window in the upper part of the gastrointestinal (GI) tract. In this study we synthesized bioactive hydrogels that have sustainable release rates for drugs in the stomach based on a hydrogel preparation technique that employs emulsifying surfactants. The emulsion gelation technique, which encapsulates oil droplets within the hydrogels during crosslinking, was used to decrease their specific gravity in aqueous environments, resulting in floating drug release depots. Properties such as swelling, buoyancy, density and drug release were manipulated by changing the polymer concentrations, surfactant percentages and the oil:polymer ratios. The relationship between these properties and the hydrogel's floating lag time was documented. The potential for this material to be used as a floating drug delivery system was demonstrated. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Interaction between a surface quasi-geostrophic buoyancy anomaly jet and internal vortices

    Science.gov (United States)

    Reinaud, J. N.; Dritschel, D. G.; Carton, X.

    2017-08-01

    This paper addresses the dynamical coupling of the ocean's surface and the ocean's interior. In particular, we investigate the dynamics of an oceanic surface jet and its interaction with vortices at depth. The jet is induced by buoyancy (density) anomalies at the surface. We first focus on the jet alone. The linear stability indicates there are two modes of instability: the sinuous and the varicose modes. When a vortex in present below the jet, it interacts with it. The velocity field induced by the vortex perturbs the jet and triggers its destabilisation. The jet also influences the vortex by pushing it under a region of co-operative shear. Strong jets may also partially shear out the vortex. We also investigate the interaction between a surface jet and a vortex dipole in the interior. Again, strong jets may partially shear out the vortex structure. The jet also modifies the trajectory of the dipole. Dipoles travelling towards the jet at shallow incidence angles may be reflected by the jet. Vortices travelling at moderate incidence angles normally cross below the jet. This is related to the displacement of the two vortices of the dipole by the shear induced by the jet. Intense jets may also destabilise early and form streets of billows. These billows can pair with the vortices and separate the dipole.

  9. Plate coupling across the northern Manila subduction zone deduced from mantle lithosphere buoyancy

    Science.gov (United States)

    Lo, Chung-Liang; Doo, Wen-Bin; Kuo-Chen, Hao; Hsu, Shu-Kun

    2017-12-01

    The Manila subduction zone is located at the plate boundary where the Philippine Sea plate (PSP) moves northwestward toward the Eurasian plate (EU) with a high convergence rate. However, historically, no large earthquakes greater than Mw7 have been observed across the northern Manila subduction zone. The poorly understood plate interaction between these two plates in this region creates significant issues for evaluating the seismic hazard. Therefore, the variation of mantle lithospheric buoyancy is calculated to evaluate the plate coupling status across the northern Manila subduction zone, based on recently published forward gravity modeling constrained by the results of the P-wave seismic crustal structure of the TAIGER (Taiwan Integrated Geodynamic Research) project. The results indicate weak plate coupling between the PSP and EU, which could be related to the release of the overriding PSP from the descending EU's dragging force, which was deduced from the higher elevation of the Luzon arc and the fore-arc basin northward toward the Taiwan orogen. Moreover, serpentinized peridotite is present above the plate boundary and is distributed more widely and thickly closer to offshore southern Taiwan orogen. We suggest that low plate coupling may facilitate the uplifting of serpentinized mantle material up to the plate boundary.

  10. Hypergravity to Explore the Role of Buoyancy in Boiling in Porous Media

    Science.gov (United States)

    Lioumbas, John S.; Krause, Jutta; Karapantsios, Thodoris D.

    2013-02-01

    Boiling in porous media is an active topic of research since it is associated with various applications, e.g. microelectronics cooling, wetted porous media as thermal barriers, food frying. Theoretical expressions customary scale boiling heat and mass transfer rates with the value of gravitational acceleration. Information obtained at low gravity conditions show a deviation from the above scaling law but refers exclusively to non-porous substrates. In addition, the role of buoyancy in boiling at varying gravitational levels (i.e. from microgravity—important to satellites and future Lunar and Martial missions, to high-g body forces—associated with fast aerial maneuvers) is still unknown since most experiments were conducted over a limited range of g-value. The present work aims at providing evidence regarding boiling in porous media over a broad range of hypergravity values. For this, a special device has been constructed for studying boiling inside porous media in the Large Diameter Centrifuge (LDC at ESA/ESTEC). LDC offers the unique opportunity to cancel the shear stresses and study only the effect of increased normal forces on boiling in porous media. The device permits measurement of the temperature field beneath the surface of the porous material and video recordings of bubble activity over the free surface of the porous material. The preliminary results presented from experiments conducted at terrestrial and hypergravity conditions, reveal for the first time the influence of increased levels of gravity on boiling in porous media.

  11. Buoyancy and Pressure Induced Flow of Hot Gases in Vertical Shafts with Natural and Forced Ventilation

    Science.gov (United States)

    Jaluria, Yogesh; Tamm, Gunnar Olavi

    2014-11-01

    An experimental investigation was conducted to study buoyancy and pressure induced flow of hot gases in vertical shafts to model smoke propagation in elevator and ventilation shafts of high rise building fires. Various configurations were tested with regard to natural and forced ventilation imposed at the upper and lower surfaces of the vertical shaft. The aspect ratio was taken at a typical value of 6. From a lower vent, the inlet conditions for smoke and hot gases were varied in terms of the Reynolds and Grashof numbers. The forced ventilation at the upper or lower boundary was of the same order as the bulk shaft flow. Measurements were taken within the shaft to allow a detailed study of the steady state flow and thermal fields established for various shaft configurations and inlet conditions, from which optimal means for smoke alleviation in high rise building fires may be developed. Results indicated a wall plume as the primary transport mechanism for smoke propagating from the inlet towards the exhaust region. Recirculation and entrainment dominated at high inlet Grashof number flows, while increased inlet Reynolds numbers allowed greater mixing in the shaft. The development and stability of these flow patterns and their effects on the smoke behavior were assessed for several shaft configurations with different inlet conditions. The comparisons indicated that the fastest smoke removal and lowest overall shaft temperatures occur for a configuration with natural ventilation at the top surface and forced ventilation up from the shaft bottom.

  12. Buoyancy Effects on the Development of the Leading Vortex Ring in a Starting Jet

    Science.gov (United States)

    Marugan-Cruz, Carolina; Rodriguez-Rodriguez, Javier; Martinez-Bazan, Carlos

    2008-11-01

    The initial development of negatively buoyant jets has been investigated experimental and numerically, more specifically the role played by gravity in the development of the leading vortex ring. A classical piston-cylinder arrangement has been used to produce the negatively buoyant jets. Under the experimental conditions considered in this work, the Froude number, Fr, which compares the jet momentum and the buoyancy flux is the most important parameter characterizing the dynamics of the flow. When the value of this parameter is sufficiently small the initial vortex ring generated at the start of the motion is pushed upwards by the gravity force before it can entrain enough vorticity to acquire a self induced velocity. However when the Froude number exceeds a critical value, Frc ˜ 1, the vortex ring can travel downwards and entrainins vorticity from the trailing jet during a longer time. Total and vortex circulation, as well as the trajectory of the leading vortex have been measured to clarify the effect of gravity on the distribution of vorticity during the initial development of negatively buoyant jets.

  13. Three-dimensional buoyancy-driven convection structures in thermohaline stratification

    Directory of Open Access Journals (Sweden)

    Ye-Jun Gong

    2016-04-01

    Full Text Available We report on three-dimensional convection structures in thermohaline stratification with the high Rayleigh number RaT = 7 ⋅ 107, the diffusion ratio δ = 0.01 and various initial density stability ratios R = 0.5, 0.8, and 1.1. According to the classification of buoyancy-driven instability in the parameter space (R, δ, the three cases are referred to follow the Rayleigh-Taylor (RT mode, the mixed mode (MM and the diffusive-layer convection (DCL mode, respectively. Whether the shape of the peak is a finger under the RT mode or a spike under the MM/DLC mode, the 3D view of the interface is likely to be a rolling mountain with a doughnut-shaped vortex around the peak and a banded vortex above the ridge. The doughnut-shaped vortex is maintained around the peak if its growth continues under RT convection; otherwise, the vortex sheds off and moves upward from the peak under the DLC mode. Additionally, we have observed the previously unreported vortex stratification by the contact interface due to the differential diffusion effect.

  14. EFFECTS OF BUOYANCY RATIO ON CONVECTIVE HEAT AND SOLUTE TRANSFER IN NEWTONIAN FLUID SATURATED INCLINED POROUS CAVITY

    Directory of Open Access Journals (Sweden)

    A LATRECHE

    2014-12-01

    Full Text Available This paper summarizes a numerical study of the effects of buoyancy ratio on double-diffusive natural convection in square inclined cavity filled with fluid saturated porous media. Transverse gradients of heat and solute are applied on the two horizontal walls of the cavity, while the other two walls are impermeable and adiabatic. The Darcy model with the Boussinesq approximation is used to solve the governing equations. The flow is driven by a combined buoyancy effect due to both temperature and concentration variations. A finite volume approach has been used to solve the non-dimensional governing equations. The results are presented in streamline, isothermal, iso-concentration, Nusselt and Sherwood contours for different values of the non-dimensional governing parameters.

  15. Rise and fall of toxic benthic freshwater cyanobacteria (Anabaena spp.) in the Eel river: Buoyancy and dispersal.

    Science.gov (United States)

    Bouma-Gregson, Keith; Power, Mary E; Bormans, Myriam

    2017-06-01

    Benthic cyanobacteria in rivers produce cyanotoxins and affect aquatic food webs, but knowledge of their ecology lags behind planktonic cyanobacteria. The buoyancy of benthic Anabaena spp. mats was studied to understand implications for Anabaena dispersal in the Eel River, California. Field experiments were used to investigate the effects of oxygen bubble production and dissolution on the buoyancy of Anabaena dominated benthic mats in response to light exposure. Samples of Anabaena dominated mats were harvested from the South Fork Eel River and placed in settling columns to measure floating and sinking velocities, or deployed into in situ ambient and low light treatments to measure the effect of light on flotation. Floating and sinking occurred within minutes and were driven by oxygen bubbles produced during photosynthesis, rather than intracellular changes in carbohydrates or gas vesicles. Light experiment results showed that in a natural ambient light regime, mats remained floating for at least 4days, while in low light mats begin to sink in <24h. Floating Anabaena samples were collected from five sites in the watershed and found to contain the cyanotoxins anatoxin-a and microcystin, with higher concentrations of anatoxin-a (median 560, max 30,693ng/gDW) than microcystin (median 30, max 37ng/gDW). The ability of Anabaena mats to maintain their buoyancy will markedly increase their downstream dispersal distances. Increased buoyancy also allows toxin-containing mats to collect along shorelines, increasing threats to human and animal public health. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Large eddy simulation of fire-induced buoyancy driven plume dispersion in an urban street canyon under perpendicular wind flow.

    Science.gov (United States)

    Hu, L H; Huo, R; Yang, D

    2009-07-15

    The dispersion of fire-induced buoyancy driven plume in and above an idealized street canyon of 18 m (width) x 18 m (height) x 40 m (length) with a wind flow perpendicular to its axis was investigated by Fire Dynamics Simulator (FDS), Large Eddy Simulation (LES). Former studies, such as that by Oka [T.R. Oke, Street design and urban canopy layer climate, Energy Build. 11 (1988) 103-113], Gayev and Savory [Y.A. Gayev, E. Savory, Influence of street obstructions on flow processes within street canyons. J. Wind Eng. Ind. Aerodyn. 82 (1999) 89-103], Xie et al. [S. Xie, Y. Zhang, L. Qi, X. Tang, Spatial distribution of traffic-related pollutant concentrations in street canyons. Atmos. Environ. 37 (2003) 3213-3224], Baker et al. [J. Baker, H. L. Walker, X. M. Cai, A study of the dispersion and transport of reactive pollutants in and above street canyons--a large eddy simulation, Atmos. Environ. 38 (2004) 6883-6892] and Baik et al. [J.-J. Baik, Y.-S. Kang, J.-J. Kim, Modeling reactive pollutant dispersion in an urban street canyon, Atmos. Environ. 41 (2007) 934-949], focus on the flow pattern and pollutant dispersion in the street canyon with no buoyancy effect. Results showed that with the increase of the wind flow velocity, the dispersion pattern of a buoyant plume fell into four regimes. When the wind flow velocity increased up to a certain critical level, the buoyancy driven upward rising plume was re-entrained back into the street canyon. This is a dangerous situation as the harmful fire smoke will accumulate to pollute the environment and thus threaten the safety of the people in the street canyon. This critical re-entrainment wind velocity, as an important parameter to be concerned, was further revealed to increase asymptotically with the heat/buoyancy release rate of the fire.

  17. ACADEMIC TRAINING

    CERN Multimedia

    Françoise Benz

    2002-01-01

    25, 26, 27, 28 February and 1st March from 11.00 to 12.00 hrs - Auditorium, bldg. 500 LECTURE SERIES Neutrino masses and oscillations by A. de Rujula / CERN-TH This course will not cover its subject in the customary way. The emphasis will be on the simple theoretical concepts (helicity, handedness, chirality, Majorana masses) which are obscure in most of the literature, and on the quantum mechanics of oscillations, that ALL books get wrong. Which, hopefully, will not deter me from discussing some of the most interesting results from the labs and from the cosmos. Academic Training Françoise Benz Secretariat Tel. 73127 francoise.benz@cern.ch

  18. Effects of buoyancy and thermal radiation on MHD flow over a stretching porous sheet using homotopy analysis method

    Directory of Open Access Journals (Sweden)

    Yahaya Shagaiya Daniel

    2015-09-01

    Full Text Available This paper investigates the theoretical influence of buoyancy and thermal radiation on MHD flow over a stretching porous sheet. The model which constituted highly nonlinear governing equations is transformed using similarity solution and then solved using homotopy analysis method (HAM. The analysis is carried out up to the 5th order of approximation and the influences of different physical parameters such as Prandtl number, Grashof number, suction/injection parameter, thermal radiation parameter and heat generation/absorption coefficient and also Hartman number on dimensionless velocity, temperature and the rate of heat transfer are investigated and discussed quantitatively with the aid of graphs. Numerical results obtained are compared with the previous results published in the literature and are found to be in good agreement. It was found that when the buoyancy parameter and the fluid velocity increase, the thermal boundary layer decreases. In case of the thermal radiation, increasing the thermal radiation parameter produces significant increases in the thermal conditions of the fluid temperature which cause more fluid in the boundary layer due to buoyancy effect, causing the velocity in the fluid to increase. The hydrodynamic boundary layer and thermal boundary layer thickness increase as a result of increase in radiation.

  19. Influence of various aspects of low Reynolds number k-ε turbulence models on predicting in-tube buoyancy affected heat transfer to supercritical pressure fluids

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Chen-Ru; Zhang, Zhen [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Centre, Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China); Jiang, Pei-Xue, E-mail: jiangpx@tsinghua.edu.cn [Beijing Key Laboratory of CO_2 Utilization and Reduction Technology/Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China); Bo, Han-Liang [Institute of Nuclear and New Energy Technology of Tsinghua University, Advanced Nuclear Energy Technology Cooperation Innovation Centre, Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 100084 (China)

    2017-03-15

    Highlights: • Understanding of the mechanism of buoyancy effect on supercritical heat transfer. • Turbulence related parameters in upward and downward flows were compared. • Turbulent Prandtl number affected the prediction insignificantly. • Buoyancy production was insignificant compared with shear production. • Damping function had the greatest effect and is a priority for further modification. - Abstract: Heat transfer to supercritical pressure fluids was modeled for normal and buoyancy affected conditions using several low Reynolds number k-ε models, including the Launder and Sharma, Myong and Kasagi, and Abe, Kondoh and Nagano, with the predictions compared with experimental data. All three turbulence models accurately predicted the cases without heat transfer deterioration, but failed to accurately predict the cases with heat transfer deterioration although the general trends were captured, indicating that further improvements and modifications are needed for the low Reynolds number k-ε turbulence models to better predict buoyancy deteriorated heat transfer. Further investigations studied the influence of various aspects of the low Reynolds number k-ε turbulence models, including the turbulent Prandtl number, the buoyancy production of turbulent kinetic energy, and the damping function to provide guidelines for model development to more precisely predict buoyancy affected heat transfer. The results show that the turbulent Prandtl number and the buoyancy production of turbulent kinetic energy have little influence on the predictions for cases in this study, while new damping functions with carefully selected control parameters are needed in the low Reynolds number k-ε turbulence models to correctly predict the buoyancy effect for heat transfer simulations in various applications such as supercritical pressure steam generators (SPSGs) in the high temperature gas cooled reactor (HTR) and the supercritical pressure water reactor (SCWR).

  20. The Phoenix inner core - potential geomagnetic implications of an asymmetric buoyancy flux (Invited)

    Science.gov (United States)

    Alboussiere, T.; Deguen, R.; Melzani, M.

    2010-12-01

    The Earth's inner core is notoriously asymmetric and we propose that this could be due to an internal mode of thermal convection (Nature, 466, 2010). That mode is characterized by melting on the eastern hemisphere and crystallization on the western hemisphere, at approximately the same rate that can be significantly larger than the average growth rate of the radius of the inner core. In addition to its impact on the internal structure of the inner core, such a convection mode has implications for the outer core. From the point of view of convection in the outer core, the buoyancy flux generated at the inner core boundary is excessively asymmetric, positive on the western side, negative on the eastern side. Contrary to a previously proposed scenario (Aubert et al., Nature, 454, 2008) whereby convection in the outer core (driven by heat flux heterogeneity at the core-mantle boundary) would affect the structure of the inner core, our model suggests that the opposite might be possible: inner core convection could affect convection in the outer core through asymmetric forcing. In this talk, we shall examine to what extent this mechanism is active and we shall try to convince researchers in the field of geomagnetism to investigate the plausibility and consequences of our model of inner core convection. There are however a few hints pointing to the fact that convection in the inner core and in the outer core may be more intimately related. First, our convection model for the inner core depends on the ability of convection in the outer core to supply or extract latent heat at the inner core boundary. Secondly, the orientation of this convection can be shown to lie preferentially along the longest axis of the inner core ellipsoid: the East-West direction coincides with the direction of the degree two mass distribution of the Earth which itself can be related to plate tectonics hence heat flux at the core-mantle boundary. That coincidence shows that convection in the inner

  1. Thermo capillary and buoyancy flows instabilities; Instabilites d`ecoulements thermocapillaires et de thermogravite

    Energy Technology Data Exchange (ETDEWEB)

    Mercier, J.F.

    1997-10-22

    Fluid flows in which liquid layers are submitted to temperature gradient applied horizontally are studied. The thermo capillary and buoyancy effects are thus described. In the experiments, the form of the cell which contains the fluid is different and the fluid heating position too. Each of these experiments reveals a different aspect of the mechanism which is responsible of the flow instability. In the first experiment, the fluid is contained in a rectangular cell longer than larger and whose two longer vertical walls are differentially heated. The waves lengths, frequencies, propagation directions and instability thresholds of stationary, unsteady or oscillating modes obtained theoretically are compared to the structures observed experimentally. The instability mechanisms are essentially bound to the temperature vertical profile in the fluid and the heat exchanges between the fluid and the ambient air are particularly described. In the second experiment, the fluid is contained in an annular cell whose vertical cylindrical walls are differentially heated. The results obtained in the rectangular cell can be transposed to the annular cell substituting the constant thermal gradient of the rectangular geometry by those of the annular geometry, inversely proportional to the radial distance. The introduction of local parameters allows to show that the instability is developed at first near the inside cylinder. In the last experiment, the fluid layer is heated by an electric wire immersed in a parallel direction to the free surface. The development of an ascending vertical flow above the wire induces a deformation of the free surface which can be added to the instability mechanisms of the previous cells. (O.M.) 58 refs.

  2. Neutral Buoyancy Simulator: MSFC-Langley joint test of large space structures component assembly:

    Science.gov (United States)

    1979-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. And construction methods had to be efficient due to limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. With the help of the NBS, building a space station became more of a reality. In a joint venture between NASA/Langley Research Center in Hampton, VA and MSFC, the Assembly Concept for Construction of Erectable Space Structures (ACCESS) was developed and demonstrated at MSFC's NBS. The primary objective of this experiment was to test the ACCESS structural assembly concept for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction. Pictured is a demonstration of ACCESS.

  3. Neutral Buoyancy Test NB-15, Scientific Airlock Contingency Operations - test subject Astronaut Paul

    Science.gov (United States)

    1977-01-01

    Once the United States' space program had progressed from Earth's orbit into outerspace, the prospect of building and maintaining a permanent presence in space was realized. To accomplish this feat, NASA launched a temporary workstation, Skylab, to discover the effects of low gravity and weightlessness on the human body, and also to develop tools and equipment that would be needed in the future to build and maintain a more permanent space station. The structures, techniques, and work schedules had to be carefully designed to fit this unique construction site. The components had to be lightweight for transport into orbit, yet durable. The station also had to be made with removable parts for easy servicing and repairs by astronauts. All of the tools necessary for service and repairs had to be designed for easy manipulation by a suited astronaut. And construction methods had to be efficient due to limited time the astronauts could remain outside their controlled environment. In lieu of all the specific needs for this project, an environment on Earth had to be developed that could simulate a low gravity atmosphere. A Neutral Buoyancy Simulator (NBS) was constructed by NASA Marshall Space Flight Center (MSFC) in 1968. Since then, NASA scientists have used this facility to understand how humans work best in low gravity and also provide information about the different kinds of structures that can be built. With the help of the NBS, building a space station became more of a reality. In a joint venture between NASA/Langley Research Center in Hampton, VA and MSFC, the Assembly Concept for Construction of Erectable Space Structures (ACCESS) was developed and demonstrated at MSFC's NBS. The primary objective of this experiment was to test the ACCESS structural assembly concept for suitability as the framework for larger space structures and to identify ways to improve the productivity of space construction. Pictured is a demonstration of ACCESS.

  4. Performance enhancement of a Lorentz force velocimeter using a buoyancy-compensated magnet system

    Science.gov (United States)

    Ebert, R.; Leineweber, J.; Resagk, C.

    2015-07-01

    Lorentz force velocimetry (LFV) is a highly feasible method for measuring flow rate in a pipe or a duct. This method has been established for liquid metal flows but also for electrolytes such as saltwater. A decrease in electrical conductivity of the medium causes a decrease of the Lorentz force which needs to be resolved, affecting the accuracy of the measurement. We use an electrical force compensation (EFC) balance for the determination of the tiny force signals in a test channel filled with electrolyte solution. It is used in a 90°-rotated orientation with a magnet system hanging vertically on its load bar. The thin coupling elements of its parallel guiding system limit the mass of the magnets to 1 kg. To overcome this restriction, which limits the magnetic flux density and hence the Lorentz forces, a weight force compensation mechanism is developed. Therefore, different methods such as air bearing are conceivable, but for the elimination of additional horizontal force components which would disturb the force signal, only compensation by lift force provided by buoyancy is reasonable. We present a swimming body setup that will allow larger magnet systems than before, because a large amount of the weight force will be compensated by this lift force. Thus the implementation of this concept has to be made with respect to hydrodynamical and mechanical stability. This is necessary to avoid overturning of the swimming body setup and to prevent inelastic deformation. Additionally, the issue will be presented and discussed whether thermal convection around the lifting body diminishes the signal-to-noise ratio (SNR) significantly or not.

  5. Emotional Intelligence, Academic Procrastination and Academic ...

    African Journals Online (AJOL)

    Academic achievement is the main measure of the level of education attained, which is meant to achieve the curriculum objective of success and priority. The study investigated effect of emotional intelligence and academic procrastination on academic achievement of students in two Nigerian Universities. The study adopted ...

  6. Correlation between trainee candidate selection criteria and subsequent performance.

    Science.gov (United States)

    Selber, Jesse C; Tong, Winnie; Koshy, John; Ibrahim, Amir; Liu, Jun; Butler, Charles

    2014-11-01

    The objective of trainee recruitment is to identify candidates likely to perform well as trainees and subsequent faculty. The effectiveness of this process has not been established. The goal of this study was to identify trainee selection criteria predictive of excellent performance. Twenty-nine microsurgery fellows were enrolled from 2008 to 2012. Each candidate was interviewed and rated based on presentation, plastic surgery (PS) training experience, academic potential, personality, social skills, communication skills, and ability to be a team player. An unadjusted rank list was generated based on weighted averages, and an adjusted rank list was then generated at a faculty meeting. At the conclusion of fellowship, each fellow was rated based on the ACGME core competencies. Spearman correlation coefficients (r) were used to measure the correlations between fellow selection criteria and fellow performance. Plastic surgery training and academic potential had, by far, the strongest correlation to overall performance (r: 0.678, p competencies. When reformulated to weight PS training and academic potential more heavily than subjective criteria, the scoring system was significantly more predictive of excellent performance (r: 0.49 vs 0.70). The unadjusted rank list was more predictive of excellent performance than the adjusted rank list (r: 0.45 vs 0.65). Plastic surgery training experience and academic potential were better predictors of performance than any subjective information ascertained during the interview. Adjustments to the rank list based on faculty discussion resulted in lower performance candidates moving up in ranking. Ranking criteria and interview techniques must be refined to improve predictive power. It may be beneficial for semi-objective criteria to carry more weight than subjective criteria and raw scores to remain unadjusted by extraneous information. Copyright © 2014 American College of Surgeons. Published by Elsevier Inc. All rights reserved.

  7. Non-isothermal buoyancy-driven exchange flows in inclined pipes

    Science.gov (United States)

    Eslami, B.; Shariatnia, S.; Ghasemi, H.; Alba, K.

    2017-06-01

    We study non-isothermal buoyancy-driven exchange flow of two miscible Newtonian fluids in an inclined pipe experimentally. The heavy cold fluid is released into the light hot one in an adiabatic small-aspect-ratio pipe under the Boussinesq limit (small Atwood number). At a fixed temperature, the two fluids involved have the same viscosity. Excellent qualitative and quantitative agreement is first found against rather recent studies in literature on isothermal flows where the driving force of the flow comes from salinity as opposed to temperature difference. The degree of flow instability and mixing enhances as the pipe is progressively inclined towards vertical. Similar to the isothermal limit, maximal rate of the fluids interpenetration in the non-isothermal case occurs at an intermediate angle, β . The interpenetration rate increases with the temperature difference. The degree of fluids mixing and diffusivity is found to increase in the non-isothermal case compared to the isothermal one. There has also been observed a novel asymmetric behavior in the flow, never reported before in the isothermal limit. The cold finger appears to advance faster than the hot one. Backed by meticulously designed supplementary experiments, this asymmetric behavior is hypothetically associated with the wall contact and the formation of a warm less-viscous film of the fluid lubricating the cold more-viscous finger along the pipe. On the other side of the pipe, a cool more-viscous film forms decelerating the hot less-viscous finger. Double diffusive effects associated with the diffusion of heat and mass (salinity) are further investigated. In this case and for the same range of inclination angles and density differences, the level of flow asymmetry is found to decrease. The asymmetric behaviour of the flow is quantified over the full range of experiments. Similar to the study of Salort et al. ["Turbulent velocity profiles in a tilted heat pipe," Phys. Fluids 25(10), 105110

  8. ACADEMIC TRAINING

    CERN Multimedia

    Françoise Benz

    2002-01-01

    24, 25, 26 April LECTURE SERIES from 11.00 to 12.00 hrs - Auditorium, bldg. 500 Anti-Matter by R. LANDUA /CERN-EP Antiparticles are a crucial ingredient of particle physics and cosmology. More than 70 years after Dirac's bold prediction and the subsequent discovery of the positron in 1932, antiparticles are still in the spotlight of modern physics. This lecture for non-specialists will start with a theoretical and historical introduction. Why are antiparticles needed? Why is the (CPT) symmetry between particles and antiparticles so fundamental? What is their role in cosmology? The second part will give an overview about the many aspects of antiparticles in experimental physics: as a tool in accelerators; as a probe inside atoms or nuclei; or as an object to study fundamental symmetries. In the third part, the lecture will focus on the experimental 'antimatter' programme at the Antiproton Decelerator (AD), with special emphysis on antihydrogen production and spectroscopy. The lecture will conclude with an outl...

  9. Imagining "Alternativas" to Global, Corporate, New Economy Academic Capitalism

    Science.gov (United States)

    Rhoades, Gary; Maldonado-Maldonado, Alma; Ordorika, Imanol; Velazquez, Martin

    2004-01-01

    In this article, the authors detail the conditions and patterns of academic capitalism and the new economy in US higher education. Subsequently, a conceptual model is offered for considering the international reach and national and local patterns of academic capitalism. Further, a distinctive Mexican case of entrepreneurialism is offered. The…

  10. Malaysian University Students' Attitudes to Academic Dishonesty and Business Ethics

    Science.gov (United States)

    Ahmad, Zauwiyah; Simun, Maimun; Mohammad, Junaini

    2008-01-01

    Academic dishonesty is believed to have predictive ability for subsequent behaviours in the workplace. This study adds to the literature by investigating Malaysian business students' attitudes to academic dishonesty and their attitudes to ethics issues in business. This study also explores the association between these two constructs. The form of…

  11. Wildland fire limits subsequent fire occurrence

    Science.gov (United States)

    Sean A. Parks; Carol Miller; Lisa M. Holsinger; Scott Baggett; Benjamin J. Bird

    2016-01-01

    Several aspects of wildland fire are moderated by site- and landscape-level vegetation changes caused by previous fire, thereby creating a dynamic where one fire exerts a regulatory control on subsequent fire. For example, wildland fire has been shown to regulate the size and severity of subsequent fire. However, wildland fire has the potential to influence...

  12. Subsequent pregnancy outcome after previous foetal death

    NARCIS (Netherlands)

    Nijkamp, J. W.; Korteweg, F. J.; Holm, J. P.; Timmer, A.; Erwich, J. J. H. M.; van Pampus, M. G.

    Objective: A history of foetal death is a risk factor for complications and foetal death in subsequent pregnancies as most previous risk factors remain present and an underlying cause of death may recur. The purpose of this study was to evaluate subsequent pregnancy outcome after foetal death and to

  13. A review of subsequence time series clustering.

    Science.gov (United States)

    Zolhavarieh, Seyedjamal; Aghabozorgi, Saeed; Teh, Ying Wah

    2014-01-01

    Clustering of subsequence time series remains an open issue in time series clustering. Subsequence time series clustering is used in different fields, such as e-commerce, outlier detection, speech recognition, biological systems, DNA recognition, and text mining. One of the useful fields in the domain of subsequence time series clustering is pattern recognition. To improve this field, a sequence of time series data is used. This paper reviews some definitions and backgrounds related to subsequence time series clustering. The categorization of the literature reviews is divided into three groups: preproof, interproof, and postproof period. Moreover, various state-of-the-art approaches in performing subsequence time series clustering are discussed under each of the following categories. The strengths and weaknesses of the employed methods are evaluated as potential issues for future studies.

  14. A Review of Subsequence Time Series Clustering

    Science.gov (United States)

    Teh, Ying Wah

    2014-01-01

    Clustering of subsequence time series remains an open issue in time series clustering. Subsequence time series clustering is used in different fields, such as e-commerce, outlier detection, speech recognition, biological systems, DNA recognition, and text mining. One of the useful fields in the domain of subsequence time series clustering is pattern recognition. To improve this field, a sequence of time series data is used. This paper reviews some definitions and backgrounds related to subsequence time series clustering. The categorization of the literature reviews is divided into three groups: preproof, interproof, and postproof period. Moreover, various state-of-the-art approaches in performing subsequence time series clustering are discussed under each of the following categories. The strengths and weaknesses of the employed methods are evaluated as potential issues for future studies. PMID:25140332

  15. A learning development module to support academically ...

    African Journals Online (AJOL)

    Students believed that the LLLS module enhanced their generic skills, and that it was beneficial to them. Aspects such as motivation, time management and critical thinking improved. Furthermore, they indicated that the skills mastered during the module continued to be useful in the subsequent academic year. Conclusion.

  16. Influences of Mood on Academic Course Evaluations

    Science.gov (United States)

    Zumbach, Joerg; Funke, Joachim

    2014-01-01

    In two subsequent experiments, the influence of mood on academic course evaluation is examined. By means of facial feedback, either a positive or a negative mood was induced while students were completing a course evaluation questionnaire during lectures. Results from both studies reveal that a positive mood leads to better ratings of different…

  17. The academic rewards of socially-oriented happiness: Interdependent happiness promotes academic engagement.

    Science.gov (United States)

    Datu, Jesus Alfonso D; King, Ronnel B; Valdez, Jana Patricia M

    2017-04-01

    Interdependent happiness has been found to be positively associated with optimal psychological outcomes in collectivist cultures. However, the association between interdependent happiness and key academic outcomes has remained unexplored. The current study examined the association of interdependent happiness with key academic outcomes such as autonomous motivation, engagement, and achievement using both cross-sectional (Study 1) and longitudinal (Study 2) approaches. Study 1 revealed that interdependent happiness positively predicted academic engagement (partly) via autonomous motivation. Study 2 showed that prior interdependent happiness positively predicted subsequent academic engagement even after controlling for autoregressor effects. In addition, reciprocal associations among the key variables were found. Taken together, results of the two studies suggest that interdependent happiness plays an adaptive role in the academic context especially in a collectivist cultural setting. Theoretical and practical implications are discussed. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

  18. Commercializing Academic Research

    DEFF Research Database (Denmark)

    Czarnitzki, Dirk; Hussinger, Katrin; Schneider, Cédric

    2011-01-01

    The knowledge produced by academic scientists has been identified as a potential key driver of technological progress. Recent policies in Europe aim at increasing commercially orientated activities in academe. Based on a sample of German scientists across all fields of science, we investigate...... the importance of academic patenting. Our findings suggest that academic involvement in patenting results in a citation premium, as academic patents appear to generate more forward citations. We also find that in the European context of changing research objectives and funding sources since the mid-1990s......, the “importance” of academic patents declines over time. We show that academic entrants have patents of lower “quality” than academic incumbents but they did not cause the decline, since the relative importance of patents involving academics with an existing patenting history declined over time as well. Moreover...

  19. Reflections on academic video

    Directory of Open Access Journals (Sweden)

    Thommy Eriksson

    2012-11-01

    Full Text Available As academics we study, research and teach audiovisual media, yet rarely disseminate and mediate through it. Today, developments in production technologies have enabled academic researchers to create videos and mediate audiovisually. In academia it is taken for granted that everyone can write a text. Is it now time to assume that everyone can make a video essay? Using the online journal of academic videos Audiovisual Thinking and the videos published in it as a case study, this article seeks to reflect on the emergence and legacy of academic audiovisual dissemination. Anchoring academic video and audiovisual dissemination of knowledge in two critical traditions, documentary theory and semiotics, we will argue that academic video is in fact already present in a variety of academic disciplines, and that academic audiovisual essays are bringing trends and developments that have long been part of academic discourse to their logical conclusion.

  20. Numerical Investigation of Heat Transfer with Thermal Radiation in an Enclosure in Case of Buoyancy Driven Flow

    Directory of Open Access Journals (Sweden)

    Christoph Hochenauer

    2014-08-01

    Full Text Available The purpose of this paper is to investigate state of the art approaches and their accuracy to compute heat transfer including radiation inside a closed cavity whereas buoyancy is the only driving force. This research is the first step of an all-embracing study dealing with underhood airflow and thermal management of vehicles. Computational fluid dynamic (CFD simulation results of buoyancy driven flow inside a simplified engine compartment are compared to experimentally gained values. The test rig imitates idle condition without any working fan. Thus, the airflow is only driven by natural convection. A conventional method used for these applications is to compute the convective heat transfer coefficient and air temperature using CFD and calculate the wall temperature separately by performing a thermal analysis. The final solution results from coupling two different software tools. In this paper thermal conditions inside the enclosure are computed by the use of CFD only. The impact of the turbulence model as well as the results of various radiation models are analyzed and compared to the experimental data.

  1. Numerical investigation of double diffusive buoyancy forces induced natural convection in a cavity partially heated and cooled from sidewalls

    Directory of Open Access Journals (Sweden)

    Rasoul Nikbakhti

    2016-03-01

    Full Text Available This paper deals with a numerical investigation of double-diffusive natural convective heat and mass transfer in a cavity filled with Newtonian fluid. The active parts of two vertical walls of the cavity are maintained at fixed but different temperatures and concentrations, while the other two walls, as well as inactive areas of the sidewalls, are considered to be adiabatic and impermeable to mass transfer. The length of the thermally active part equals half of the height. The non-dimensional forms of governing transport equations that describe double-diffusive natural convection for two-dimensional incompressible flow are functions of temperature or energy, concentration, vorticity, and stream-function. The coupled differential equations are discretized via FDM (Finite Difference Method. The Successive-Over-Relaxation (SOR method is used in the solution of the stream function equation. The analysis has been done for an enclosure with different aspect ratios ranging from 0.5 to 11 for three different combinations of partially active sections. The results are presented graphically in terms of streamlines, isotherms and isoconcentrations. In addition, the heat and mass transfer rate in the cavity is measured in terms of the average Nusselt and Sherwood numbers for various parameters including thermal Grashof number, Lewis number, buoyancy ratio and aspect ratio. It is revealed that the placement order of partially thermally active walls and the buoyancy ratio influence significantly the flow pattern and the corresponding heat and mass transfer performance in the cavity.

  2. Abortions: Does It Affect Subsequent Pregnancies?

    Science.gov (United States)

    Healthy Lifestyle Getting pregnant Could an abortion increase the risk of problems in a subsequent pregnancy? Answers from Yvonne Butler Tobah, M.D. Generally, elective abortion isn't thought to cause fertility issues or ...

  3. Crohn’s Disease: The Subsequent Visit

    OpenAIRE

    Manolakis, Catherine S.; Farraye, Francis A.; Di Palma, Jack A.

    2013-01-01

    The diagnosis and subsequent management of Crohn’s disease are challenging for both the patient and the gastroenterologist. After the initial assessment, subsequent visits should assess the patient’s readiness to begin therapy, monitor progress if therapy has been initiated, assess for complications of the disease or therapy, and ensure that all appropriate health maintenance measures are current. This article is intended to be a companion to our earlier paper “Crohn’s Disease: The First Visi...

  4. Academic Delay of Gratification and Academic Achievement

    Science.gov (United States)

    Bembenutty, Hefer

    2011-01-01

    The ability to delay gratification is the cornerstone of all academic achievement and education. It is by delaying gratification that learners can pursue long-term academic and career goals. In general, "delay of gratification" refers to an individual's ability to forgo immediate rewards for the sake of more valuable ones later (Mischel, 1996).…

  5. Academic Entitlement and Academic Performance in Graduating Pharmacy Students

    OpenAIRE

    Jeffres, Meghan N.; Barclay, Sean M.; Stolte, Scott K.

    2014-01-01

    Objectives. To determine a measurable definition of academic entitlement, measure academic entitlement in graduating doctor of pharmacy (PharmD) students, and compare the academic performance between students identified as more or less academically entitled.

  6. Academic Engagement and Commercialisation

    DEFF Research Database (Denmark)

    Perkmann, Markus; Tartari, Valentina; McKelvey, Maureen

    2013-01-01

    A considerable body of work highlights the relevance of collaborative research, contract research, consulting and informal relationships for university–industry knowledge transfer. We present a systematic review of research on academic scientists’ involvement in these activities to which we refer...... as ‘academic engagement’. Apart from extracting findings that are generalisable across studies, we ask how academic engagement differs from commercialisation, defined as intellectual property creation and academic entrepreneurship. We identify the individual, organisational and institutional antecedents...

  7. Infant developmental milestones and subsequent cognitive function.

    Science.gov (United States)

    Murray, Graham K; Jones, Peter B; Kuh, Diana; Richards, Marcus

    2007-08-01

    Developmental delay is associated with a subsequent diagnosis of learning disability. However, the relationship between the age of reaching infant developmental milestones and later intellectual function within the general population remains unresolved. We hypothesized that earlier attainment of developmental milestones would be associated with better subsequent intellectual performance throughout the range of abilities, rather than confined to extremes. Developmental data were obtained at age 2 years in the National Survey of Health and Development, a representative sample of 5,362 children born in the United Kingdom in 1946. Data on intellectual function and educational attainment at ages 8, 26, and 53 years were also obtained. Multiple linear regression and logistic regression were used to analyze the effect of age of reaching developmental milestones on subsequent cognition and educational attainment. The age of reaching developmental milestones was associated with intellectual performance at ages 8, 26, and 53 years; for every month earlier a child learned to stand, there was, on average, a gain of one half of one intelligence quotient point at age 8. Speech development had a small but statistically significant effect on subsequent educational attainment (later developers were less likely to progress beyond basic education); this effect was not apparent for motor development. Effect sizes were reduced when the slowest developers were excluded, but many effects remained significant. The association between later development and poorer subsequent intellectual function is small, but it does have theoretical implications; we suggest it is secondary to suboptimal cortical-subcortical connectivity.

  8. What Is Academic Vocabulary?

    Science.gov (United States)

    Baumann, James F.; Graves, Michael F.

    2010-01-01

    In this article, the authors address the construct of "academic vocabulary." First, they attempt to bring some clarity to a constellation of terms surrounding academic vocabulary. Second, they compare and contrast definitions of academic vocabulary. Third, they review typologies that researchers and writers have proposed to organize academic…

  9. Academic Inbreeding in Nursing

    Science.gov (United States)

    Miller, Michael H.

    1977-01-01

    Academic inbreeding, the employment for faculty positions of persons who receive their graduate training at the same academic institution, is considered detrimental to an institution's academic environment. Results of a study conducted at 54 universities revealed that almost half the faculty (48 percent) in collegiate nursing programs are drawn…

  10. Vagotomy and subsequent development of diabetes

    DEFF Research Database (Denmark)

    Starup-Linde, Jakob; Gejl, Michael; Borghammer, Per

    2016-01-01

    registration of vagotomy and/or upper gastrointestinal disease in the period 1977-2011. Controls had no subsequent diagnosis of diabetes and were matched by incidence density sampling, age and gender. Logistic regression analyses were conducted. RESULTS: 501,724 diabetes patients and 1,375,567 matched controls......BACKGROUND: Vagal signaling is involved in gastric emptying and the secretion and effect of a number of hormones regulating gluco-metabolic processes and, thus, crucial for metabolic homeostasis. PURPOSE: We hypothesized that vagotomy would increase the risk of developing type 2 diabetes...... and examined the association between vagotomy and subsequent development of diabetes. METHODS: A nested case-control study was conducted with information on cases and controls from the Danish National Patient Registry. Cases included individuals with a diabetes diagnosis subsequent (>12months) to the first...

  11. Preeclampsia, gestational hypertension and subsequent hypothyroidism

    Science.gov (United States)

    Männistö, Tuija; Karumanchi, S. Ananth; Pouta, Anneli; Vääräsmäki, Marja; Mendola, Pauline; Miettola, Satu; Surcel, Heljä-Marja; Bloigu, Aini; Ruokonen, Aimo; Järvelin, Marjo-Riitta; Hartikainen, Anna-Liisa; Suvanto, Eila

    2012-01-01

    Objectives To evaluate the effect of preeclampsia (PE) and gestational hypertension (GH) on subsequent hypothyroidism. Recent studies suggest that women with PE have increased risk for reduced thyroid function, but the association between PE and GH with overt hypothyroidism has not been examined. Study design Two prospective population-based cohort studies, the Northern Finland Birth Cohorts 1966 and 1986, followed women who had PE (N=955), GH (N=1449) or were normotensive (N=13531) during pregnancy. Finnish national registers were used to confirm subsequent hypothyroidism. Adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) estimated hypothyroidism risk when comparing women with PE or GH with normotensive women. Main outcome measures Primary hypothyroidism during follow-up of 20–40 years. Results The subsequent prevalence of hypothyroidism was higher among women with PE (4.0%) and GH (4.5%) compared with normotensive women (3.5%), but the risk increase was not significant (aHR for PE 1.13, 95%CI 0.80–1.59 and aHR for GH 1.11, 95%CI 0.85–1.45). Subgroup analysis among nulliparous women revealed a significant association between late PE and subsequent hypothyroidism (aHR 1.82, 95%CI 1.04–3.19). Early or recurrent PE were not associated with hypothyroidism (aHR 0.93, 95%CI 0.46–1.81 and aHR 1.35, 95%CI 0.63–2.88, respectively). Conclusions Overall, PE or GH during pregnancy was not significantly associated with subsequent hypothyroidism in Finnish women after 20–40 years of follow-up. However, late PE in nulliparous women was associated with a 1.8-fold increased risk of subsequent hypothyroidism, a finding that merits further study in other populations. PMID:23439671

  12. Buoyancy-driven mixing of fluids in a confined geometry; Melange gravitationnel de fluides en geometrie confinee

    Energy Technology Data Exchange (ETDEWEB)

    Hallez, Y

    2007-12-15

    The present work based on Direct Numerical Simulations is devoted to the study of mixing between two miscible fluids of different densities. The movement of these fluids is induced by buoyancy. Three geometries are considered: a cylindrical tube, a square channel and a plane two-dimensional flow. For cylindrical tubes, the results of numerical simulations fully confirm previous experimental findings by Seon et al., especially regarding the existence of three different flow regimes, depending on the tilt angle. The comparison of the various geometries shows that tridimensional flows in tubes or channels are similar, whereas the two-dimensional model fails to give reliable information about real 3D flows, either from a quantitative point of view or for a phenomenological understanding. A peculiar attention is put on a joint analysis of the concentration and vorticity fields and allows us to explain several subtle aspects of the mixing dynamics. (author)

  13. Spatio-temporal variability in western Baltic cod early life stage survival mediated by egg buoyancy, hydrography and hydrodynamics

    DEFF Research Database (Denmark)

    Hinrichsen, H-H.; Hüssy, K.; Huwer, B.

    2012-01-01

    spatial (within and between different spawning areas) and temporal (interannual and seasonal) dynamics. A spatially and temporally highly-resolved biophysical model of the Baltic Sea was used to describe mortalities and survival success of eggs and yolk-sac larvae—represented by individual, virtual......Spatio-temporal variability in western Baltic cod early life stage survival mediated by egg buoyancy, hydrography and hydrodynamics. – ICES Journal of Marine Science, 69: 1744–1752.To disentangle the effects of different drivers on recruitment variability of marine fish, a spatially and temporally...... drifters—as predicted proportions of drifters that either died due to bottom contact or lethal temperatures, or that survived up to the end of the yolk-sac larval stage. The environmental conditions allowing survival of cod and yolk-sac larvae indicate that favourable conditions predominately occurred...

  14. 75 FR 82005 - Proposed Subsequent Arrangement

    Science.gov (United States)

    2010-12-29

    ... Nonproliferation and International Security, Department of Energy. ACTION: Proposed subsequent arrangement. SUMMARY..., Canada, to Korea Nuclear Fuel Co. Ltd. in Yuson-Gu, Taejon, South Korea. The material, which is currently... Energy. Thomas P. D'Agostino, Administrator, National Nuclear Security Administration. [FR Doc. 2010...

  15. Compressed Subsequence Matching and Packed Tree Coloring

    DEFF Research Database (Denmark)

    Bille, Philip; Cording, Patrick Hagge; Gørtz, Inge Li

    2017-01-01

    We present a new algorithm for subsequence matching in grammar compressed strings. Given a grammar of size n compressing a string of size N and a pattern string of size m over an alphabet of size \\(\\sigma \\), our algorithm uses \\(O(n+\\frac{n\\sigma }{w})\\) space and \\(O(n+\\frac{n\\sigma }{w}+m\\log N...

  16. 7 CFR 1781.22 - Subsequent loans.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Subsequent loans. 1781.22 Section 1781.22 Agriculture Regulations of the Department of Agriculture (Continued) RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE (CONTINUED) RESOURCE CONSERVATION AND DEVELOPMENT (RCD) LOANS AND WATERSHED (WS) LOANS AND ADVANCES § 1781.22...

  17. Pregnancy scares and subsequent unintended pregnancy

    Directory of Open Access Journals (Sweden)

    Heather Gatny

    2014-11-01

    Full Text Available Background: A substantial number of young women experience pregnancy scares - thinking they might be pregnant, and later discovering that they are not. Although pregnancy scares are distressing events, little is known about who experiences them and whether they are important to our understanding of unintended pregnancy. Objective: We describe the young women who experience pregnancy scares, and examine the link between pregnancy scares and subsequent unintended pregnancy. Methods: We used data from the Relationship Dynamics and Social Life Study. T-tests and regression analyses were conducted using baseline and weekly data to estimate relationships between respondent characteristics and subsequent pregnancy scares. Event history methods were used to assess pregnancy scares as a predictor of unintended pregnancy. Results: Nine percent of the young women experienced a pregnancy scare during the study. African-American race, lack of two-parent family structure, lower GPA, cohabitation, and sex without birth control prior to the study are associated with experiencing a pregnancy scare and with experiencing a greater number of pregnancy scares. Further, experiencing a pregnancy scare is strongly associated with subsequent unintended pregnancy, independent of background factors. Forty percent of the women who experienced a pregnancy scare subsequently had an unintended pregnancy during the study period, relative to only 11Š of those who did not experience a pregnancy scare. Conclusions: Young women from less advantaged backgrounds are more likely to experience a pregnancy scare, and pregnancy scares are often followed by an unintended pregnancy.

  18. Subsequent Reproductive Performance in Survivors of Complicated ...

    African Journals Online (AJOL)

    There were 2 cases of postpartum hemorrhage. 103 (44%) of the subjects who still desired pregnancy were yet unable to conceive. Conclusions The subsequent reproductive performance in survivors of complicated abortion appears to be largely characterized by a high rate of sub-fertility, fetal wastage and preterm ...

  19. Weight at birth and subsequent fecundability

    DEFF Research Database (Denmark)

    Wildenschild, Cathrine; Riis, Anders H; Ehrenstein, Vera

    2014-01-01

    OBJECTIVE: To examine the association between a woman's birth weight and her subsequent fecundability. METHOD: In this prospective cohort study, we included 2,773 Danish pregnancy planners enrolled in the internet-based cohort study "Snart-Gravid", conducted during 2007-2012. Participants were 18...

  20. 7 CFR 3560.73 - Subsequent loans.

    Science.gov (United States)

    2010-01-01

    ... accordance with 7 CFR part 1940, subpart G. (f) Design requirements. All improvements, repairs, and... applicant must obtain architectural services when any of the following conditions exist: (1) Enclosed space... being proposed requires architectural services. (h) Restrictive-use requirements. Subsequent loans are...

  1. Academic Training: Academic Training Lectures-Questionnaire

    CERN Multimedia

    2004-01-01

    ACADEMIC TRAINING Françoise Benz tel. 73127 academic.training@cern.ch SUGGEST AND WIN! Its time to plan the 2004-2005 lecture series. From today until March 19 you have the chance to give your contribution to planning for next year's Academic Training Lecture Series. At the web site: http://cern.ch/Academic.Training/questionnaire you will find questionnaires proposing topics in high energy physics, applied physics and science and society. Answering the questionnaire will help ensure that the selected topics are as close as possible to your interests. In particular requests and comments from students will be much appreciated. To encourage your contribution, the AT Committee will reward one lucky winner with a small prize, a 50 CHF coupon for a book purchase at the CERN bookshop.

  2. It takes three to tango: 1. Simulating buoyancy-driven flow in the presence of large viscosity contrasts

    Science.gov (United States)

    Suckale, Jenny; Nave, Jean-Christophe; Hager, Bradford H.

    2010-07-01

    Buoyancy-driven flow is of fundamental importance for numerous geodynamic phenomena. Since the equations of motion governing multiphase flow are rarely amenable to analytical solutions, numerical simulations provide a compelling alternative. They offer the ability to carefully analyze flow phenomena under differing regimes, initial conditions, and flow dynamics. The three key challenges in these computations are (1) the accurate solution of the equations of motion in the presence of large viscosity contrasts, (2) the representation of strongly deforming interfaces between different fluids, and (3) the accurate coupling of fluid and interface solver. In three dimensions, these challenges become even more intricate, and the appropriate choice of numerical scheme has a profound influence on the tractability, accuracy, robustness, and efficiency of the computational simulation. This is the first paper of two that examine numerical simulations of buoyancy-driven flow in the presence of large viscosity contrasts. In this paper, we present our numerical approach which tackles the above three main challenges through a combination of three numerical methods, namely, (1) an extended ghost fluid type discretization which we developed specifically for the Stokes regime, (2) the level set method, and (3) the extension velocity technique. We find that all three components are crucial to obtain a versatile numerical tool for simulating complex structures in evolving flow. We validate our code by reproducing four benchmark problems in two and three dimensions. We devote special attention to comparing our method to other existing techniques, detailing the advantages of this approach. Finally, we highlight several types of geophysical flow problems for which we believe our method to be well suited.

  3. Academic self-concept, autonomous academic motivation, and academic achievement : mediating and additive effects

    OpenAIRE

    Guay, Frédéric; Ratelle, Catherine; Roy, Amélie; Litalien, David

    2010-01-01

    Three conceptual models were tested to examine the relationships among academic self-concept, autonomous academic motivation, and academic achievement. This allowed us to determine whether 1) autonomous academic motivation mediates the relation between academic self-concept and achievement, 2) academic self-concept mediates the relation between autonomous academic motivation and achievement, or 3) both motivational constructs have an additive effect on academic achievement. A total of 925 hig...

  4. The influence of different salinity conditions on egg buoyancy and development and yolk sac larval survival and morphometric traits of Baltic Sea sprat (Sprattus sprattus balticus Schneider

    Directory of Open Access Journals (Sweden)

    Christoph Petereit

    2009-10-01

    Full Text Available The small pelagic sprat (Sprattus sprattus is a key ecologic player in the Baltic Sea. However, there is long-term variability in recruitment which is thought to be influenced by fluctuations in abiotic and biotic conditions experienced during the early life stages. This study concentrates on the influence of different ambient salinities on sprat egg development, egg buoyancy and survival as well as early yolk sac larval morphometric traits. Egg buoyancy significantly decreased with increasing salinity experienced during fertilization and/or incubation experiments. Field egg buoyancy measurements in 2007 and 2008 exhibited annual and seasonal differences in specific gravity, potentially associated with changes in adult sprat vertical distribution. Neither egg development time nor the duration of the yolk sac phase differed among salinity treatments. At eye pigmentation, larval standard length exhibited high variance among individuals but did not differ among treatments. The largest ecological impact of salinity experienced during spawning was the modification the buoyancy of eggs and yolk sac larvae, which determines their vertical habitat in the Baltic Sea. There are strong thermo- and oxyclines in the Baltic Sea, and thus salinity can indirectly impact the survival of these early life stages by modifying the ambient temperatures and oxygen conditions experienced.

  5. On the relative importance of thermal and chemical buoyancy in regular and impact-induced melting in a Mars-like planet

    Science.gov (United States)

    Ruedas, Thomas; Breuer, Doris

    2017-07-01

    We ran several series of two-dimensional numerical mantle convection simulations representing in idealized form the thermochemical evolution of a Mars-like planet. In order to study the importance of compositional buoyancy of melting mantle, the models were set up in pairs of one including all thermal and compositional contributions to buoyancy and one accounting only for the thermal contributions. In several of the model pairs, single large impacts were introduced as causes of additional strong local anomalies, and their evolution in the framework of the convecting mantle was tracked. The models confirm that the additional buoyancy provided by the depletion of the mantle by regular melting can establish a global stable stratification of the convecting mantle and throttle crust production. Furthermore, the compositional buoyancy is essential in the stabilization and preservation of local compositional anomalies directly beneath the lithosphere and offers a possible explanation for the existence of distinct, long-lived reservoirs in the Martian mantle. The detection of such anomalies by geophysical means is probably difficult, however; they are expected to be detected by gravimetry rather than by seismic or heat flow measurements. The results further suggest that the crustal thickness can be locally overestimated by up to ˜20 km if impact-induced density anomalies in the mantle are neglected.

  6. Academic Self-Concept, Autonomous Academic Motivation, and Academic Achievement: Mediating and Additive Effects

    Science.gov (United States)

    Guay, Frederic; Ratelle, Catherine F.; Roy, Amelie; Litalien, David

    2010-01-01

    Three conceptual models were tested to examine the relationships among academic self-concept, autonomous academic motivation, and academic achievement. This allowed us to determine whether 1) autonomous academic motivation mediates the relation between academic self-concept and achievement, 2) academic self-concept mediates the relation between…

  7. Accumulation and subsequent utilization of waste heat

    Science.gov (United States)

    Koloničný, Jan; Richter, Aleš; Pavloková, Petra

    2016-06-01

    This article aims to introduce a special way of heat accumulation and primary operating characteristics. It is the unique way in which the waste heat from flue gas of biogas cogeneration station is stored in the system of storage tanks, into the heat transfer oil. Heat is subsequently transformed into water, from which is generated the low-pressure steam. Steam, at the time of peak electricity needs, spins the special designed turbine generator and produces electrical energy.

  8. Induced abortion and subsequent pregnancy duration

    DEFF Research Database (Denmark)

    Zhou, Wei Jin; Sørensen, Henrik Toft; Olsen, Jørn

    1999-01-01

    OBJECTIVE: To examine whether induced abortion influences subsequent pregnancy duration. METHODS: Women who had their first pregnancies during 1980, 1981, and 1982 were identified in three Danish national registries. A total of 15,727 women whose pregnancies were terminated by first-trimester ind......OBJECTIVE: To examine whether induced abortion influences subsequent pregnancy duration. METHODS: Women who had their first pregnancies during 1980, 1981, and 1982 were identified in three Danish national registries. A total of 15,727 women whose pregnancies were terminated by first......-trimester induced abortions were compared with 46,026 whose pregnancies were not terminated by induced abortions. All subsequent pregnancies until 1994 were identified by register linkage. RESULTS: Preterm and post-term singleton live births were more frequent in women with one, two, or more previous induced...... abortions. After adjusting for potential confounders and stratifying by gravidity, the odds ratios of preterm singleton live births in women with one, two, or more previous induced abortions were 1.89 (95% confidence interval [CI] 1.70, 2.11), 2.66 (95% CI 2.09, 3.37), and 2.03 (95% CI 1.29, 3...

  9. Association of Periodontitis and Subsequent Depression

    Science.gov (United States)

    Hsu, Chih-Chao; Hsu, Yi-Chao; Chen, Hsuan-Ju; Lin, Che-Chen; Chang, Kuang-Hsi; Lee, Chang-Yin; Chong, Lee-Won; Kao, Chia-Hung

    2015-01-01

    Abstract Periodontitis is a systemic and chronic inflammatory disease associated with multiple physical conditions. Distress and depression are other problems affecting the progression of periodontitis. However, the causal relationship between depression and periodontitis has not been adequately investigated. This aim of this study was to determine the association between periodontitis and the subsequent development of depression. We identified 12,708 patients with newly diagnosed periodontitis from 2000 to 2005 and 50,832 frequency-matched individuals without periodontitis. Both groups were followed until diagnosed with depression, withdrawal from the National Health Insurance program, or the end of 2011. The association between periodontitis and depressio was analyzed using Cox proportional hazard regression models. The incidence density rate of depression was higher in the periodontitis group than in the nonperiodontitis group, with an adjusted hazard ratio of 1.73 (95% confidence interval 1.58–1.89) when adjusting for sex, age, and comorbidity. Cox models revealed that periodontitis was an independent risk factor for depression in patients, except for comorbidities of diabetes mellitus (DM), alcohol abuse, and cancer. Periodontitis may increase the risk of subsequent depression and was suggested an independent risk factor regardless of sex, age, and most comorbidities. However, DM, alcohol abuse, and cancer may prevent the development of subsequent depression because of DM treatment, the paradoxical effect of alcohol, and emotional distress to cancer, respectively. Prospective studies on the relationship between periodontitis and depression are warranted. PMID:26705230

  10. Reactions to abortion and subsequent mental health.

    Science.gov (United States)

    Fergusson, David M; Horwood, L John; Boden, Joseph M

    2009-11-01

    There has been continued interest in the extent to which women have positive and negative reactions to abortion. To document emotional reactions to abortion, and to examine the links between reactions to abortion and subsequent mental health outcomes. Data were gathered on the pregnancy and mental health history of a birth cohort of over 500 women studied to the age of 30. Abortion was associated with high rates of both positive and negative emotional reactions; however, nearly 90% of respondents believed that the abortion was the right decision. Analyses showed that the number of negative responses to the abortion was associated with increased levels of subsequent mental health disorders (Pabortion and reporting negative reactions had rates of mental health disorders that were approximately 1.4-1.8 times higher than those not having an abortion. Abortion was associated with both positive and negative emotional reactions. The extent of negative emotional reactions appeared to modify the links between abortion and subsequent mental health problems.

  11. Relationship of adolescent self-esteem to selected academic variables.

    Science.gov (United States)

    Filozof, E M; Albertin, H K; Jones, C R; Steme, S S; Myers, L; McDermott, R J

    1998-02-01

    This study investigated whether self-esteem precedes various academic behaviors and beliefs among 593 high school students (63.7% female, 60.9% African American). Measures of home and school self-esteem, grade point average, perceived academic standing and progress, and educational plans were collected by survey and archival review of grade and attendance records at the beginning (pre-test) and end of the school year (post-test). Self-esteem and academic variables differed by gender, race, and guardianship. Self-esteem related significantly to academics and absenteeism. Results suggest selected academic variables predict self-esteem even when the effects of gender, race, and guardianship are removed and pretest self-esteem scores are controlled. In conclusion, student academic performance influences subsequent academic and home self-esteem. Creation of positive academic experiences for youth may be a critical activity, since experts contend that low self-esteem is associated with subsequent behavioral problems. The markedly lower self-esteem of Native American and Hispanic youth warrants further investigation.

  12. Ethics and academic integrity.

    Science.gov (United States)

    Milton, Constance L

    2015-01-01

    Academics from across the globe must navigate ever-increasing demands for research, practice, and educational productivity. With the increased demands, nurse faculty must choose value priorities and actions that reflect academic integrity. What does it mean to choose actions that reflect personal integrity in the academic arena? This article begins an important nursing philosophical and theoretical discussion that members and future members of the discipline of nursing must reflect upon and grapple with as they consider what it potentially means to act with straight thinking and integrity in academics. © The Author(s) 2014.

  13. The Academic Structure in Japan: Institutional Hierarchy and Academic Mobility.

    Science.gov (United States)

    Arimoto, Akira

    The characteristics of the Japanese academic structure are examined with attention to the evolution of institutional hierarchy, the closed academic structure, and the effects of the academic structure upon academic research. The evolution of Japan's institutional hierarchy in academics has been tightly related to factors of nationalism,…

  14. Effect of antenatal exposure to maternal smoking on behavioural problems and academic achievement in childhood : prospective evidence from a Dutch birth cohort

    NARCIS (Netherlands)

    Batstra, L; Hadders-Algra, M; Neeleman, J

    2003-01-01

    Aim: To examine effects of maternal smoking during pregnancy on academic achievement and emotional and behavioural problems during childhood. Methods: Least squares regression was used to examine associations between maternal smoking prior to delivery and subsequent academic performance and

  15. Chronic myeloproliferative neoplasms and subsequent cancer risk

    DEFF Research Database (Denmark)

    Frederiksen, H.; Farkas, Dora Kormendine; Christiansen, C.F.

    2011-01-01

    Patients with chronic myeloproliferative neoplasms, including essential thrombocythemia (ET), polycythemia vera (PV), and chronic myeloid leukemia (CML), are at increased risk of new hematologic malignancies, but their risk of nonhematologic malignancies remains unknown. In the present study, we...... diagnosed with a chronic myeloproliferative neoplasm during 1977-2008. We compared the incidence of subsequent cancer in this cohort with that expected on the basis of cancer incidence in the general population (standardized incidence ratio). Overall, ET, PV, and CML patients were at increased risk...... conclude that patients with chronic myeloproliferative neoplasms are at increased risk of developing a new malignant disease....

  16. Correlating selection criteria with subsequent performance as residents.

    Science.gov (United States)

    Dirschl, Douglas R; Dahners, Laurence E; Adams, George L; Crouch, John H; Wilson, Frank C

    2002-06-01

    The objective of this study was to determine which criteria in the residency application had the highest correlation with subsequent performance of orthopaedic residents. Data collected from the application files of 58 residents included scores on standardized tests, number of honors grades in the basic and clinical years of medical school, election to Alpha Omega Alpha, numbers of research projects and publications, and numbers of extracurricular activities. Measures of performance included scores on the Orthopaedic In-Training Examination and American Board of Orthopaedic Surgery Part I Examination, and faculty evaluations of overall, cognitive, affective, and psychomotor performance. The number of honors grades on clinical rotations was the strongest predictor of performance, whereas election to Alpha Omega Alpha was second. The only other significant correlation was between the number of fine motor activities and psychomotor performance. None of the predictor variables had a significant correlation with Orthopaedic In-Training Examination or American Board of Orthopaedic Surgery Examination scores. Consistency between faculty rankings in each of the four categories was supported by regression analysis. From the results of this study, it appears that academic performance in clinical clerkships in medical school is the most predictive of resident performance. Range restriction in the data available for orthopaedic residency applicants, however, likely precludes the development of a reliable model to assist in the selection of orthopaedic residents.

  17. Workplace bullying and subsequent health problems.

    Science.gov (United States)

    Nielsen, Morten Birkeland; Magerøy, Nils; Gjerstad, Johannes; Einarsen, Ståle

    2014-07-01

    Cross-sectional studies demonstrate that exposure to bullying in the workplace is positively correlated with self-reported health problems. However, these studies do not provide a basis to draw conclusions on the extent to which bullying leads to increased health problems or whether health problems increase the risk of being bullied. To provide better indications of a causal relationship, knowledge from prospective studies on the association between bullying in the workplace and health outcomes is therefore summarised. We conducted a systematic literature review of original articles from central literature databases on longitudinal associations between bullying in the workplace and health. Average associations between bullying and health outcomes are calculated using meta-analysis. A consistent finding across the studies is that exposure to bullying is significantly positively related to mental health problems (OR =1.68; 95% KI 1.35-2.09) and somatic symptoms (OR = 1.77; 95% KI 1.41-2.22) over time. Mental health problems are also associated with subsequent exposure to bullying (OR = 1.74; 95% KI 1.44-2.12). Bullying is positively related to mental health problems and somatic symptoms. The association between mental health problems and subsequent bullying indicates a self-reinforcing process between mental health and bullying. The methodological quality of the studies that were conducted is relatively sound. However, based on the existing knowledge base there are no grounds for conclusions regarding an unambiguous causal relationship between bullying and health.

  18. Autoimmune disease and subsequent urological cancer.

    Science.gov (United States)

    Liu, Xiangdong; Ji, Jianguang; Forsti, Asta; Sundquist, Kristina; Sundquist, Jan; Hemminki, Kari

    2013-06-01

    We examined the subsequent risk and prognosis of urological cancer in individuals diagnosed with autoimmune disease. We systematically analyzed the risk and prognosis of prostate, kidney and bladder cancers in individuals diagnosed with any of 33 autoimmune diseases based on a national Swedish database for 1964 through 2008. The SIR and HR were calculated for subsequent urological cancers between 1964 and 2008 in individuals hospitalized for autoimmune disease. An increased SIR for urological cancer was recorded after 26 autoimmune diseases. An increased HR for cancer specific survival was noted after 4 autoimmune diseases and for overall survival after 18. The highest SIRs were seen for kidney cancer after polyarteritis nodosa (2.85) and polymyositis/dermatomyositis (2.68), and for bladder cancer after polymyositis/dermatomyositis (2.45). The highest risk of prostate cancer (1.70) was observed after polyarteritis nodosa. SIRs were lower during followup from 1990 to 2008 compared to the previous period. Individuals diagnosed with prostate and kidney cancers showed an improved cancer specific prognosis, in contrast to the poorer overall prognosis for all 3 urological cancers. The risk of urological cancer was increased after all autoimmune diseases. The most significant changes after individual autoimmune diseases were toward higher risk. Survival data were reassuring since autoimmune disease only marginally influences the prognosis of cancer specific mortality. However, overall survival was decreased for the 3 types of cancer. Copyright © 2013 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  19. Gender and Academic Integrity.

    Science.gov (United States)

    Hendershott, Anne; Drinan, Patrick F.; Cross, Megan

    1999-01-01

    Investigates the academic integrity climate of a mid-sized, comprehensive, private university. Seeks to assess gender differences in motivations surrounding cheating behaviors among 532 undergraduate students. Findings indicate that while both males and females are reluctant to report instances of academic dishonesty that they witness, there…

  20. Networking into Academic Discourse.

    Science.gov (United States)

    Warschauer, Mark

    2002-01-01

    Examines the experiences of three instructors in Hawaii who have attempted to integrate online communication into their academic writing courses. Emphasizes that the underlying assumptions of what academic writing constitutes are fundamental in influencing how teachers integrate technology in the classroom. (Author/VWL)

  1. Arbitration in Academe.

    Science.gov (United States)

    Douglas, Joel, Ed.

    1989-01-01

    Questions and issues critical to an understanding of arbitration in higher education are discussed. Aspects of the academic arbitration model are defined. The following four topics are examined: (1) the procedural similarities and differences between academic arbitration and the industrial model; (2) the possible inherent conflict between academic…

  2. Academic Identities under Threat?

    Science.gov (United States)

    Clegg, Sue

    2008-01-01

    This article focuses on the lived experience of practising academics as part of an inquiry into the vexed question of "academic identities". Identity is understood not as a fixed property, but as part of the lived complexity of a person's project. The article reports on data from a small study in one university. The data suggest that…

  3. Association of Academic Physiatrists

    Science.gov (United States)

    ... currPanel = 0; autoPlayDelaySeconds = slidePanel(currPanel); autoPlay(); }, (autoPlayDelaySeconds*1000)); } $(document).ready(function (){ $slider.children('.slide-panel.notactive').hide(); ... Academic Home for Physiatry The Association of Academic Physiatrists ( ...

  4. Impulsivity and Academic Cheating

    Science.gov (United States)

    Anderman, Eric M.; Cupp, Pamela K.; Lane, Derek

    2009-01-01

    The authors examined the relations between academic cheating and impulsivity in a large sample of adolescents enrolled in high school health education classes. Results indicated that impulsivity predicts academic cheating for students who report extensive involvement in cheating. However, students who engage in extensive cheating are less likely…

  5. Academic Work and Performativity

    Science.gov (United States)

    Kenny, John

    2017-01-01

    Neoliberal reforms in higher education have resulted in corporate managerial practices in universities and a drive for efficiency and productivity in teaching and research. As a result, there has been an intensification of academic work, increased stress for academics and an emphasis on accountability and performativity in universities. This paper…

  6. Marketing Academic Libraries

    Science.gov (United States)

    Mallon, Melissa, Ed.

    2013-01-01

    Ask any academic librarian if marketing their library and its services is an important task, and the answer will most likely be a resounding "yes!" Particularly in economically troubled times, librarians are increasingly called upon to promote their services and defend their library's worth. Since few academic libraries have in-house marketing…

  7. Confronting Academic Dishonesty.

    Science.gov (United States)

    Saunders, Edward J.

    1993-01-01

    The issue of academic dishonesty, including plagiarism, cheating on tests, and falsification of data by students, is examined. Legal cases are reviewed; the University of Iowa school of social work's policy on academic misconduct is presented; and other avenues of intervention and prevention are discussed. (Author/MSE)

  8. Thinking Academic Freedom

    Science.gov (United States)

    Lange, Lis

    2016-01-01

    This lecture argues that the politicisation and instrumentalisation of the university caused by neoliberal frames has as a result the depoliticisation of knowledge and of the academic as individual. This depoliticisation has turned academic freedom into a right to disengage not only from the political fight around these issues but also from the…

  9. Perceptions of Challenges and Values of Higher Education between First Generation and Subsequent Generations on Male Latinos

    Science.gov (United States)

    Sanchez, Sylvia Andrea

    2012-01-01

    This research study focused on the perceptions of challenges and values of higher education between first-generation and subsequent-generation male Latinos and their factors affecting academic success. According to Gandara (2009), Latinas are making advancements in higher education, being committed to continue with college, and maintaining higher…

  10. Does Academic Work Make Australian Academics Happy?

    Science.gov (United States)

    Duncan, Roderick; Tilbrook, Kerry; Krivokapic-Skoko, Branka

    2015-01-01

    Happiness research is a rapidly-growing area in social psychology and has emphasised the link between happiness and workplace productivity and creativity for knowledge workers. Recent articles in this journal have raised concerns about the level of happiness and engagement of Australian academics with their work, however there is little research…

  11. Activity recognition from minimal distinguishing subsequence mining

    Science.gov (United States)

    Iqbal, Mohammad; Pao, Hsing-Kuo

    2017-08-01

    Human activity recognition is one of the most important research topics in the era of Internet of Things. To separate different activities given sensory data, we utilize a Minimal Distinguishing Subsequence (MDS) mining approach to efficiently find distinguishing patterns among different activities. We first transform the sensory data into a series of sensor triggering events and operate the MDS mining procedure afterwards. The gap constraints are also considered in the MDS mining. Given the multi-class nature of most activity recognition tasks, we modify the MDS mining approach from a binary case to a multi-class one to fit the need for multiple activity recognition. We also study how to select the best parameter set including the minimal and the maximal support thresholds in finding the MDSs for effective activity recognition. Overall, the prediction accuracy is 86.59% on the van Kasteren dataset which consists of four different activities for recognition.

  12. Coexisting contraction-extension consistent with buoyancy of the crust and upper mantle in North-Central Italy

    CERN Document Server

    Aoudia, A; Ismail-Zadeh, A T; Panza, G F; Pontevivo, A

    2002-01-01

    The juxtaposed contraction and extension observed in the crust of the Italian Apennines and elsewhere has, for a long time, attracted the attention of geoscientists and is a long-standing enigmatic feature. Several models, invoking mainly external forces, have been put forward to explain the close association of these two end-member deformation mechanisms clearly observed by geophysical and geological investigations. These models appeal to interactions along plate margins or at the base of the lithosphere such as back-arc extension or shear tractions from mantle flow or to subduction processes such as slab roll back, retreat or pull and detachment. We present here a revisited crust and upper mantle model that supports delamination processes beneath North-Central Italy and provides a new background for the genesis and age of the recent magmatism in Tuscany. Although external forces must have been important in the building up of the Apennines, we show that internal buoyancy forces solely can explain the coexist...

  13. Experimental and numerical study of buoyancy-driven single bubble dynamics in a vertical Hele-Shaw cell

    Science.gov (United States)

    Wang, Xue; Klaasen, Bart; Degrève, Jan; Blanpain, Bart; Verhaeghe, Frederik

    2014-12-01

    Buoyancy-driven single bubble behaviour in a vertical Hele-Shaw cell with various gap Reynolds numbers Re(h/d)2 has been studied. Two gap thicknesses, h = 0.5 mm (Re(h/d)2 = 1.0-8.5) and 1 mm (Re(h/d)2 = 6.0-50) were used to represent low and high gap Reynolds number flow. Periodic shape oscillation and path vibration were observed once the gap Reynolds number exceeds the critical value of 8.5. The bubble behaviour was also numerically simulated by taking a two-dimensional volume of fluid method coupled with a continuum surface force model and a wall friction model in the commercial computational fluid dynamics package Fluent. By adjusting the viscous resistance values, the bubble dynamics in the two gap thicknesses can be simulated. For the main flow properties including shape, path, terminal velocity, horizontal vibration, and shape oscillation, good agreement is obtained between experiment and simulation. The estimated terminal velocity is 10%-50% higher than the observed one when the bubble diameter d ≤ 5 mm, h = 0.5 mm and 9% higher when d ≤ 18 mm, h = 1.0 mm. The estimated oscillation frequency is 50% higher than the observed value. Three-dimensional effects and spurious vortices are most likely the reason for this inaccuracy. The simulation confirms that the thin liquid films between gas bubbles and the cell walls have a limited effect on the bubble dynamics.

  14. Large-Eddy Simulation of Oil Slicks from Deep Water Blowouts: Effects of Droplet Buoyancy and Langmuir Turbulence

    Science.gov (United States)

    Chamecki, M.; Yang, D.; Meneveau, C. V.

    2013-12-01

    Deep water blowouts generate plumes of oil droplets that rise through, and interact with various layers of the ocean. When plumes reach the ocean mixed layer (OML), the interactions among oil droplet plume, Ekman Spiral and Langmuir turbulence strongly affect the final rates of dilution and bio-degradation. The present study aims at developing a large-eddy simulation (LES) capability for the study of the physical distribution and dispersion of oil droplets under the action of physical oceanographic processes in the OML. In the current LES approach, the velocity and temperature fields are simulated using a hybrid pseudo-spectral and finite-difference scheme; the oil field is described by an Eulerian concentration field and it is simulated using a bounded finite-volume scheme. Fluid accelerations induced by buoyancy of the oil plume are included, and a number of subgrid-scale models for the flow solver are implemented and tested. The LES capability is then applied to the simulation of oil plume dispersion in the OML. Graphical visualization of the LES results shows surface oil slick distribution consistent with the satellite and aerial images of surface oil slicks reported in the literature. Different combinations of Lamgmuir turbulence and droplet size lead to different oil slick patterns at the surface and significantly impact oil concentration. Possible effects for bio-degradation are also discussed. Funding from the GoMRI RFP-II is gratefully acknowledged.

  15. Upshot of binary chemical reaction and activation energy on carbon nanotubes with Cattaneo-Christov heat flux and buoyancy effects

    Science.gov (United States)

    Lu, Dianchen; Ramzan, M.; Ahmad, Shafiq; Chung, Jae Dong; Farooq, Umer

    2017-12-01

    A mathematical model is framed to discuss the flow of carbon nanotube-suspended nanofluids with Cattaneo-Christov heat flux and binary chemical reaction. The flow analysis is performed in attendance of heat generation/absorption, energy activation, and buoyancy effects past a nonlinear stretched surface embedded in a non-Darcy permeable medium. A combination of varied nanotubes with base fluids is also taken into account. The Runge-Kutta fifth-order Fehlberg technique is engaged to find the numerical solution of a highly nonlinear problem. The impact of sundry parameters on involved distributions is illustrated graphically with requisite discussion keeping in view their physical aspects. Different tables that comprise numerically calculated values of numerous sundry parameters highlighting their physical significance are also erected. It is witnessed that velocity and temperature profiles are enhanced for mounting values of nanoparticle volume fraction parameters. Further, it is seen that for enhancing the value of the Prandtl number, the temperature profile decreases rapidly for single-walled carbon nanotubes than multi-walled carbon nanotubes.

  16. Experimental Research on Thermocapillary-Buoyancy Migration Interaction of Axisymmetric Two Drops by Using Digital Holographic Interferometry

    Science.gov (United States)

    Zhang, Shuoting; Duan, Li; Kang, Qi

    2017-12-01

    The migration and interaction of axisymmetric two drops in a vertical temperature gradient is investigated experimentally on the ground. A silicon oil is used as the continuous phase, and a water-ethanol mixture is used as the drop phase, respectively. The migration and interaction of two drops, under the combined effects of buoyancy and thermocapillary, is recorded by a digital holographic interferometry measurement in the experiment to analyse the velocities and temperature distribution of the drops. As a result, when two drops migrate together, the drop affects the other drop by perturbing the temperature field around itself. For the leading drop, the velocity is faster than the one of the isolated drop, and the maximum of the interfacial temperature distribution is larger than the one of the isolated drop. For the trailing drop, the velocity is slower than the one of the isolated drop, and the maximum of the interfacial temperature distribution is less than the one of the isolated drop. The influence of the dimensionless initial distance between the drop centres to the drop migration is discussed in detail in this study.

  17. Academic entitlement and academic performance in graduating pharmacy students.

    Science.gov (United States)

    Jeffres, Meghan N; Barclay, Sean M; Stolte, Scott K

    2014-08-15

    To determine a measurable definition of academic entitlement, measure academic entitlement in graduating doctor of pharmacy (PharmD) students, and compare the academic performance between students identified as more or less academically entitled. Graduating students at a private health sciences institution were asked to complete an electronic survey instrument that included demographic data, academic performance, and 2 validated academic entitlement instruments. One hundred forty-one of 243 students completed the survey instrument. Fourteen (10%) students scored greater than the median total points possible on 1 or both of the academic entitlement instruments and were categorized as more academically entitled. Less academically entitled students required fewer reassessments and less remediation than more academically entitled students. The highest scoring academic entitlement items related to student perception of what professors should do for them. Graduating pharmacy students with lower levels of academic entitlement were more academically successful than more academically entitled students. Moving from an expert opinion approach to evidence-based decision-making in the area of academic entitlement will allow pharmacy educators to identify interventions that will decrease academic entitlement and increase academic success in pharmacy students.

  18. Academic Entitlement and Academic Performance in Graduating Pharmacy Students

    Science.gov (United States)

    Barclay, Sean M.; Stolte, Scott K.

    2014-01-01

    Objectives. To determine a measurable definition of academic entitlement, measure academic entitlement in graduating doctor of pharmacy (PharmD) students, and compare the academic performance between students identified as more or less academically entitled. Methods. Graduating students at a private health sciences institution were asked to complete an electronic survey instrument that included demographic data, academic performance, and 2 validated academic entitlement instruments. Results. One hundred forty-one of 243 students completed the survey instrument. Fourteen (10%) students scored greater than the median total points possible on 1 or both of the academic entitlement instruments and were categorized as more academically entitled. Less academically entitled students required fewer reassessments and less remediation than more academically entitled students. The highest scoring academic entitlement items related to student perception of what professors should do for them. Conclusion. Graduating pharmacy students with lower levels of academic entitlement were more academically successful than more academically entitled students. Moving from an expert opinion approach to evidence-based decision-making in the area of academic entitlement will allow pharmacy educators to identify interventions that will decrease academic entitlement and increase academic success in pharmacy students. PMID:25147388

  19. Collective academic supervision

    DEFF Research Database (Denmark)

    Nordentoft, Helle Merete; Thomsen, Rie; Wichmann-Hansen, Gitte

    2013-01-01

    are interconnected. Collective Academic Supervision provides possibilities for systematic interaction between individual master students in their writing process. In this process they learn core academic competencies, such as the ability to assess theoretical and practical problems in their practice and present them...... process. This article fills these gaps by discussing potentials and challenges in “Collective Academic Supervision”, a model for supervision at the Master of Education in Guidance at Aarhus University in Denmark. The pedagogical rationale behind the model is that students’ participation and learning...

  20. Thermo capillary and buoyancy convection in a fluid locally heated on its free surface; Convection thermocapillaire et thermogravitaire dans un fluide chauffe localement sur sa surface libre

    Energy Technology Data Exchange (ETDEWEB)

    Favre, E.

    1997-09-26

    coupled buoyancy and thermo-capillary convection lead to a convective motion of the interface liquid/gas which drastically changes the heat and mass transfer across the liquid layer. Two experiments were considered, depending on the fluid: oil or mercury. The liquid is set in a cooled cylindrical vessel, and heated by a heat flux across the center of the free surface. The basic flow, in the case of oil, is a torus. When the heat parameter increases, a stationary flow appears as petals or rays when the aspect ratio. The lateral confinement selects the azimuthal wavelength. In the case of petals-like flow, a sub-critical Hopf bifurcation is underlined. The turbulence is found to be `weak`, even for the largest values of the Marangoni number (Ma = 1.3 10{sup 5}). In the case of mercury, the thermo-capillary effect is reduced to zero to impurities at the surface which have special trajectories we describe and compare to a simpler experiment. Only the buoyancy forces induce a unstationary, weakly turbulent flow as soon as the heating power exceeds 4W (Ra = 4.5 10{sup 3}, calculated with h = 1 mm). The past part concerns the analysis of the effect on the flow of the boundary conditions, the geometry, the Prandtl number and the buoyancy force with the help of the literature. Results concerning heat transfer, in particular the exponent of the law Nusselt number vs. heating power, were compared with available data. (author) 115 refs.

  1. An Integrated Capillary, Buoyancy, and Viscous-Driven Model for Brine/CO2Relative Permeability in a Compositional and Parallel Reservoir Simulator

    KAUST Repository

    Kong, X.

    2012-11-03

    The effectiveness of CO2 storage in the saline aquifers is governed by the interplay of capillary, viscous, and buoyancy forces. Recent experimental study reveals the impact of pressure, temperature, and salinity on interfacial tension (IFT) between CO2 and brine. The dependence of CO2-brine relative permeability and capillary pressure on pressure (IFT) is also clearly evident in published experimental results. Improved understanding of the mechanisms that control the migration and trapping of CO2 in subsurface is crucial to design future storage projects that warrant long-term and safe containment. Simulation studies ignoring the buoyancy and also variation in interfacial tension and the effect on the petrophysical properties such as trapped CO2 saturations, relative permeability, and capillary pressure have a poor chance of making accurate predictions of CO2 injectivity and plume migration. We have developed and implemented a general relative permeability model that combines effects of pressure gradient, buoyancy, and IFT in an equation of state (EOS) compositional and parallel simulator. The significance of IFT variations on CO2 migration and trapping is assessed.

  2. Academic Training: 2004 - 2005 ACADEMIC TRAINING PROGRAMME

    CERN Multimedia

    Françoise Benz

    2004-01-01

    1st Term - 01 October to 17 December 2004 REGULAR LECTURE PROGRAMME New Trends in Fusion Research by A. Fasoli, EPFL, Lausanne, CH 11, 12, 13 October Physics at e+e- linear collider by K. Desch, DESY, Hamburg, D 15, 16, 17, 18, 19 November LECTURE SERIES FOR POSTGRADUATE STUDENTS Standard Model by R. Barbieri, CERN-PH-TH 6, 7, 8, 9 10 December The lectures are open to all those interested, without application. The abstract of the lectures, as well as any change to the above information (title, dates, time, place etc) will be published in the CERN Bulletin, the WWW, and by notices before each term and for each series of lectures. ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch

  3. Early postpartum discharge and subsequent breastfeeding.

    Science.gov (United States)

    Janson, S; Rydberg, B

    1998-12-01

    Early postpartum discharge of babies was gradually introduced in Sweden in the 1980s on ideological grounds, based on the premise that maternity wards were unnatural settings for mothers and babies and hampered breastfeeding. From about 1990, early discharge was used as a means to reduce costs. The purpose of this study was to examine if mandated early discharge at Central Hospital of Karlstad, Sweden, influenced subsequent breastfeeding. Breastfeeding outcomes of infants up to six months of age of all births in 1993 (n = 3231) were compared with the outcome of newborns in 1990 (n = 1462). Breastfeeding at six months postpartum continued to increase during the early 1990s for both healthy and sick infants, irrespective of whether or not they were discharged early. In infants born in 1995 the breastfeeding rate at six months was 64 percent for healthy newborns and 53 percent for sick newborns. Factors other than the time of discharge, most likely a positive change of attitude in society and vigorous introduction of the Baby Friendly Hospital Initiative, seem to have been more important for successful breastfeeding.

  4. Mental imagery affects subsequent automatic defense responses

    Directory of Open Access Journals (Sweden)

    Muriel A Hagenaars

    2015-06-01

    Full Text Available Automatic defense responses promote survival and appropriate action under threat. They have also been associated with the development of threat-related psychiatric syndromes. Targeting such automatic responses during threat may be useful in populations with frequent threat exposure. Here, two experiments explored whether mental imagery as a pre-trauma manipulation could influence fear bradycardia (a core characteristic of freezing during subsequent analogue trauma (affective picture viewing. Image-based interventions have proven successful in the treatment of threat-related disorders, and are easily applicable. In Experiment 1 43 healthy participants were randomly assigned to an imagery script condition. Participants executed a passive viewing task with blocks of neutral, pleasant and unpleasant pictures after listening to an auditory script that was either related (with a positive or a negative outcome or unrelated to the unpleasant pictures from the passive viewing task. Heart rate was assessed during script listening and during passive viewing. Imagining negative related scripts resulted in greater bradycardia (neutral-unpleasant contrast than imagining positive scripts, especially unrelated. This effect was replicated in Experiment 2 (N = 51, again in the neutral-unpleasant contrast. An extra no-script condition showed that bradycardia was not induced by the negative related script, but rather that a positive script attenuated bradycardia. These preliminary results might indicate reduced vigilance after unrelated positive events. Future research should replicate these findings using a larger sample. Either way, the findings show that highly automatic defense behavior can be influenced by relatively simple mental imagery manipulations.

  5. Academic streaming in Europe

    DEFF Research Database (Denmark)

    Falaschi, Alessandro; Mønster, Dan; Doležal, Ivan

    2004-01-01

    The TF-NETCAST task force was active from March 2003 to March 2004, and during this time the mem- bers worked on various aspects of streaming media related to the ultimate goal of setting up common services and infrastructures to enable netcasting of high quality content to the academic community...... in Europe. We report on a survey of the use of streaming media in the academic community in Europe, an open source content delivery network, and a portal for announcing live streaming events to the global academic community.......The TF-NETCAST task force was active from March 2003 to March 2004, and during this time the mem- bers worked on various aspects of streaming media related to the ultimate goal of setting up common services and infrastructures to enable netcasting of high quality content to the academic community...

  6. Academic librarianship today

    CERN Document Server

    2017-01-01

    Intended for use by both librarians and students in LIS programs, Academic Librarianship Today is the most current, comprehensive overview of the field available today. Key features include: Each chapter was commissioned specifically for this new book, and the authors are highly regarded academic librarians or library school faculty— or both Cutting-edge topics such as open access, copyright, digital curation and preservation, emerging technologies, new roles for academic librarians, cooperative collection development and resource sharing, and patron-driven acquisitions are explored in depth Each chapter ends with thought-provoking questions for discussion and carefully constructed assignments that faculty can assign or adapt for their courses The book begins with Gilman’s introduction, an overview that briefly synthesizes the contents of the contributors’ chapters by highlighting major themes. The main part of the book is organized into three parts: The Academic Library Landscape Today, ...

  7. Sexual Harassment in Academe.

    Science.gov (United States)

    Tuana, Nancy

    1985-01-01

    The extent and nature of sexual harassment of students by college faculty are examined, and practical suggestions for institutions to eradicate academic sexual harassment are made, including a published code of conduct and educational programs. (MSE)

  8. Declaration of Academic Freedom

    Directory of Open Access Journals (Sweden)

    Gökhan ÇETİNSAYA

    2014-04-01

    Full Text Available 1. Universities are the institutions where all the opinions, various truth claims as well as social and political problems are discussed in a liberal and civilized way and the complicated problems are expressed clearly without any oppression and prevention. 2. Academic freedom includes first and foremost the right of freedom of research and thus freedom of using the essential knowledge methods, the right of possessing the necessary tools and conditions required for the research and the rights of scientific production, informing, learning and dissemination. 3. Academics possess the rights to benefit from the academic freedom without any limitation, to research and investigate according to their own preferences and interests, and to teach these without being exposed to any oppression and prevention. 4. This freedom of teaching that the academics have should not be used in a manner restricting students' freedom of learning; academics should avoid from being dogmatic in the research and education processes and respect students' rights of thinking differently and expressing themselves. 5. Academics accordingly should lead the students to evaluate and understand the new thoughts as a whole and to be tolerant to the thoughts they do not agree and to think in various ways. Also, academics should encourage the students to create their own opinions based on evidences and enable them to express these opinions freely and respect their freedom of expression. 6. Campuses should be safe environments where the students can express their own opinions freely. Suppressing the intellectual diversity and the plurality of viewpoints will decrease the productivity of teaching and learning process, restrict students' freedom of learning, and constrain the chance of formation of critical and in-depth thinking. 7. Critical thinking develops only in the campuses where various thoughts are expressed in a liberal way. Students should feel that they would not be prevented

  9. Relocalising academic literacy

    DEFF Research Database (Denmark)

    Clemensen, Nana; Holm, Lars

    2017-01-01

    This article contributes to the continuing discussion about academic literacy in international higher education. Approaching international study programmes as temporary educational contact zones, marked by a broad diversity in students’ educational and discursive experiences, we examine...... the negotiation and relocalisation of academic literacy among students of the international master’s programme, Anthropology of Education and Globalisation (AEG), University of Aarhus, Denmark. The article draws on an understanding of academic literacy as a local practice situated in the social and institutional...... contexts in which it appears. Based on qualitative interviews with eleven AEG-students, we analyse students’ individual experiences of, and perspectives on, the academic literacy practices of this study programme. Our findings reveal contradictory understandings of internationalism and indicate a learning...

  10. Perspectives on academic dishonesty.

    Science.gov (United States)

    Bradshaw, M J; Lowenstein, A J

    1990-01-01

    Academic dishonest behaviors, such as lying, cheating, and plagiarism, are destructive and must be recognized and addressed early in the development of professional nurses. Faculty must be concerned with the relationship between student integrity in the classroom and clinical or professional behaviors. The authors discuss student motivation and attitudes toward unethical practices, faculty responses, and responsibilities when these incidents arise, and strategies for preventing academic dishonesty.

  11. The reciprocal longitudinal relationship between the parent-adolescent relationship and academic stress in Korea

    National Research Council Canada - National Science Library

    Kim, Eunkyung; Lee, Mijin

    2013-01-01

    .... The results revealed that the parent-adolescent relationship and academic stress experienced by students during 1 year were significant predictors of the levels of stress felt in subsequent years...

  12. How Personal Factors Influence Academic Behavior and GPA in African American STEM Students

    National Research Council Canada - National Science Library

    Scherer, Stephen; Talley, Cheryl P; Fife, John E

    2017-01-01

    ...’ personal factors that influence academic behavior (PIAB) and, subsequently, achievement. This study aimed to expand the current literature by developing a new model to assess the influence of PIABs on student success.

  13. Subclinical atherosclerosis and subsequent cognitive function.

    Science.gov (United States)

    Rossetti, Heidi C; Weiner, Myron; Hynan, Linda S; Cullum, C Munro; Khera, Amit; Lacritz, Laura H

    2015-07-01

    To examine the relationship between measures of subclinical atherosclerosis and subsequent cognitive function. Participants from the Dallas Heart Study (DHS), a population-based multiethnic study of cardiovascular disease pathogenesis, were re-examined 8 years later (DHS-2) with the Montreal Cognitive Assessment (MoCA); N = 1904, mean age = 42.9, range 8-65. Associations of baseline measures of subclinical atherosclerosis (coronary artery calcium, abdominal aortic plaque, and abdominal aortic wall thickness) with MoCA scores measured at follow-up were examined in the group as a whole and in relation to age and ApoE4 status. A significant linear trend of successively lower MoCA scores with increasing numbers of atherosclerotic indicators was observed (F(3, 1150) = 5.918, p = .001). CAC was weakly correlated with MoCA scores (p = .047) and MoCA scores were significantly different between participants with and without CAC (M = 22.35 vs 23.69, p = 0.038). With the exception of a small association between abdominal AWT and MoCA in subjects over age 50, abdominal AWT and abdominal aortic plaque did not correlate with MoCA total score (p ≥ .052). Cognitive scores and atherosclerosis measures were not impacted by ApoE4 status (p ≥ .455). In this ethnically diverse population-based sample, subclinical atherosclerosis was minimally associated with later cognitive function in middle-aged adults. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. The Academic Spoken Word List

    Science.gov (United States)

    Dang, Thi Ngoc Yen; Coxhead, Averil; Webb, Stuart

    2017-01-01

    The linguistic features of academic spoken English are different from those of academic written English. Therefore, for this study, an Academic Spoken Word List (ASWL) was developed and validated to help second language (L2) learners enhance their comprehension of academic speech in English-medium universities. The ASWL contains 1,741 word…

  15. Academic Writing and Tacit Knowledge

    Science.gov (United States)

    Elton, Lewis

    2010-01-01

    The genre of academic writing is discipline dependent, so that neither specialists in academic writing nor practising academics in a discipline can, independently of each other, provide students with the necessary help to develop the ability to write in their academic disciplines. Furthermore, the rules are largely tacit, i.e. they are not…

  16. The characteristics of mantle lithosphere buoyancy revealed from the northern Manila subduction zone to the active collision in Taiwan region

    Science.gov (United States)

    Lo, Chung-Liang; Doo, Wen-Bin; Kuo-Chen, Hao; Hsu, Shu-Kun; Lin, Jing-Yi

    2017-04-01

    It has been widely studied on the complexity tectonic structure in the active Taiwan orogenesis, since the converging between the Philippine Sea plate (PSP) and the Eurasian plate (EU) along with the Manila subduction zone extended from the Philippine to offshore the southern Taiwan and the Ryukyu subduction zone in the east. Considering the separate contribution of the crust and the mantle lithosphere to the topography, we try to examine the mantle lithosphere buoyancy (Hm) behavior from the northern Manila subduction zone to the active collision in Taiwan region. In this study, we present several Hm profiles across the northern Manila subduction zone and the Taiwan island. In order to calculate the Hm, the crust structures are constrained by the forward gravity modeling, in which the density is provided from the multi-channel seismic data and on land seismic data (thanks to the Taiwan Integrated Geodynamic Research (TAIGER) project). The result shows that the Hm across the northern Manila subduction zone displays apparent undulations, and undulates more drastic approaching the north end of the subduction zone. It implies that the plate coupling between the PSP and the EU here is weak. The Hm across the southern Taiwan undulates still, but the amplitudes are smaller with relative gentle undulations. This reflects the contribution from the slab underneath while the initial collision occurs in south Taiwan. Into the central Taiwan, the Hm pattern behaves undulating mild comparing with that across the subduction zone because the slab structure effects not obvious. Besides, the Hm in the central Taiwan primarily is affects by both the thickening crust and high elevation caused by the strong lateral external compression stress.

  17. Academic self-concept and academic achievement: relations and causal ordering.

    Science.gov (United States)

    Marsh, Herbert W; Martin, Andrew J

    2011-03-01

    BACKGROUND. A positive self-concept is valued as a desirable outcome in many disciplines of psychology as well as an important mediator to other outcomes. AIMS. The present review examines support for the reciprocal effects model (REM) that posits academic self-concept (ASC) and achievement are mutually reinforcing, each leading to gains in the other - and its extension to other achievement domains. METHOD. We review theoretical, methodological, and empirical support for the REM. Critical features in this research are a theoretical emphasis on multidimensional perspectives that focus on specific components of self-concept and a methodological focus on a construct validity approach to evaluating the REM. RESULTS. Consistent with these distinctions, REM research and a comprehensive meta-analysis show that prior ASC has direct and indirect effects on subsequent achievement, whilst the effects of self-esteem and other non-academic components of self-concept are negligible. We then provide an overview of subsequent support for the generality of the REM for: young children, cross-cultural, health (physical activity), and non-elite (gymnastics) and elite (international swimming championships) sport. CONCLUSION. This research is important in demonstrating that increases in ASC lead to increases in subsequent academic achievement and other desirable educational outcomes. Findings confirm that not only is self-concept an important outcome variable in itself, it also plays a central role in affecting other desirable educational outcomes. Implications for educational practice are discussed. ©2010 The British Psychological Society.

  18. A Contextualized View on Long-Term Predictors of Academic Performance

    Science.gov (United States)

    Gut, Janine; Reimann, Giselle; Grob, Alexander

    2013-01-01

    Several studies show that parents' and teachers' perceptions of children's academic competence are important predictors of children's subsequent academic performance. However, there is a lack of evidence on what precedes these perceptions as well as the dynamics within a comprehensive model. The aim of this study was to investigate the…

  19. Relations of Perceived Maternal Parenting Style, Practices, and Learning Motivation to Academic Competence in Chinese Children

    Science.gov (United States)

    Cheung, Cecilia S.; McBride-Chang, Catherine

    2008-01-01

    A measure of academic parenting practices was developed through parent and teacher interviews and subsequently administered to 91 Hong Kong Chinese fifth graders, who also rated their mothers' restrictiveness and concern, school motivation, and self-perceived academic competence. Children's actual school grades were obtained from school records.…

  20. Examining bias in a test of academic literacy: Does the Test of ...

    African Journals Online (AJOL)

    Examining bias in a test of academic literacy: Does the Test of Academic Literacy Levels (TALL) treat students from English and African language backgrounds ... then articulating this in detailed specifications for subtests and item types, and subsequently setting benchmarks for both test reliability and item productivity, there ...

  1. Undisciplined beginnings, academic success, and discursive psychology.

    Science.gov (United States)

    Billig, Michael

    2012-09-01

    This paper reflects on the conditions under which Discourse and social psychology, Common knowledge, and the author's Arguing and thinking were written. These books, which were independently conceived, were not specifically written as contributions to 'discursive psychology', for discursive psychology did not exist at that time. Their authors were rejecting conventional approaches to doing psychological research. The paper discusses what it takes for a new academic movement, such as discursive psychology, to be successfully established in the current climate of 'academic capitalism'. Two requirements are particularly mentioned: the necessity for a label and the necessity for adherents to be recruited. Of the three books, only Discourse and social psychology was outwardly recruiting its readers to a new way of doing social psychology. Arguing and thinking, with its celebration of ancient rhetoric, was much more ambiguous in its aims. It was turning away from present usefulness towards the past. By claiming to be 'an antiquarian psychologist' the author was rejecting disciplinary thinking. The paper also considers the intellectual costs of establishing a new specialism or sub-discipline. The 'first generation' may have freedom, but success can bring about a narrowing of perspectives and the development of orthodoxies for subsequent academic generations. This applies as much to the development of experimental social psychology as to discursive psychology. These processes are particular enhanced in the present socio-economic situation of contemporary universities, which make it more difficult for young academics to become, in the words of William James, 'undisciplinables'. ©2012 The British Psychological Society.

  2. The academically gifted female student in science

    Science.gov (United States)

    Brown, Paula R.

    The protocol of this study was designed to investigate the factors three gifted, young women perceived as influencing their successful transition from an accelerated science high school program to three accelerated university science programs. The research design was a mixed methods study involving three gifted women as they maneuvered through a high school magnet program for science and matriculated into separate university honors programs for science majors. As high school graduates, these women also achieved honors and citations for academic excellence. During their initial years of college, these students maintained outstanding grades in rigorous programs for science majors. These criteria yielded three, gifted female students who proved to be resilient and committed to meeting the demands of an academic program of science. In an attempt to understand the influential factors in the academic lives of these students, a narrative inquiry as well as a quantitative component comprised of three inventories for descriptive data were selected. The impetus for this research resided in the need to better understand the factors contributing to the shaping of the self-identity of the gifted female student as she achieved academic success in the typically, male dominated science classrooms; subsequently, the guidance by parents and educators may prove influential in developing the achievement orientation within the self-identity of the young woman.

  3. Whistleblowing in academic medicine

    Science.gov (United States)

    Rhodes, R; Strain, J

    2004-01-01

    The authors present and discuss cases of academic medicine failing to address unethical behaviour in academic science and, thereby, illustrate the scope and seriousness of the problem. The Olivieri/Apotex affair is just another instance of academic medicine's dereliction in a case of scientific fraud and misconduct. Instead of vigorously supporting their faculty member in her efforts to honestly communicate her findings and to protect patients from the risks associated with the use of the study drug, the University of Toronto collaborated with the Apotex company's "stalling tactics," closed down Dr Olivieri's laboratory, harassed her, and ultimately dismissed her. The authors argue that the incentives for addressing problematic behaviour have to be revised in order to effect a change in the current pattern of response that occurs in academic medicine. An externally imposed realignment of incentives could convert the perception of the whistleblower, from their present caste as the enemy within, into a new position, as valued friend of the institution. The authors explain how such a correction could encourage appropriate reactions to scientific misconduct from academic medicine. PMID:14872069

  4. CAEP 2015 Academic Symposium: Leadership within the emergency medicine academic community and beyond.

    Science.gov (United States)

    Sinclair, Doug; Worthington, James R; Joubert, Gary; Holroyd, Brian R; Stempien, James; Letovsky, Eric; Rutledge, Tim; LeBlanc, Constance; Pitters, Carrol; McCallum, Andrew; Carr, Brendan; Gerace, Rocco; Stiell, Ian G; Artz, Jennifer D; Christenson, Jim

    2016-05-01

    A panel of emergency medicine (EM) leaders endeavoured to define the key elements of leadership and its models, as well as to formulate consensus recommendations to build and strengthen academic leadership in the Canadian EM community in the areas of mentorship, education, and resources. The expert panel comprised EM leaders from across Canada and met regularly by teleconference over the course of 9 months. From the breadth of backgrounds and experience, as well as a literature review and the development of a leadership video series, broad themes for recommendations around the building and strengthening of EM leadership were presented at the CAEP 2015 Academic Symposium held in Edmonton, Alberta. Feedback from the attendees (about 80 emergency physicians interested in leadership) was sought. Subsequently, draft recommendations were developed by the panel through attendee feedback, further review of the leadership video series, and expert opinion. The recommendations were distributed to the CAEP Academic Section for further feedback and updated by consensus of the expert panel. The methods informed the panel who framed recommendations around four themes: 1) leadership preparation and training, 2) self-reflection/emotional intelligence, 3) academic leadership skills, and 4) gender balance in academic EM leadership. The recommendations aimed to support and nurture the next generation of academic EM leaders in Canada and included leadership mentors, availability of formal educational courses/programs in leadership, self-directed education of aspiring leaders, creation of a Canadian subgroup with the AACEM/SAEM Chair Development Program, and gender balance in leadership roles. These recommendations serve as a roadmap for all EM leaders (and aspiring leaders) to build on their success, inspire their colleagues, and foster the next generation of Canadian EM academic leaders.

  5. Academic Training: 2003 - 2004 Academic Training Programme

    CERN Multimedia

    2004-01-01

    ACADEMIC TRAINING Françoise Benz tel. 73127 academic.training@cern.ch 3rd Term - 5 April to 2nd July 2004 REGULAR LECTURE PROGRAMME 19, 20, 21, 22, 23 April Complex Systems, Chaos and Measurements by P. Collet / Ecole Polytechnique, Palaiseau, France 26, 27, 28, 29 April The Theory of Heavy Ion Collisions by U. Wiedemann / CERN-PH/TH 10, 11, 12, 13, 14 May Particle Identification at the LHC by D. Fournier / LAL, Orsay, France 1, 2, 3, 4 June Neural Systems, Genetic Algorithms by V. Robles Forcada and M. Perez Hernandez / Univ. Politecnica de Madrid E. 7, 8, 9, June Real Time Process Control by T. Riesco / CERN-TS 14, 15, 16, 17, 18 June The Cosmic Microwave Background by M. Zaldarriaga / Harvard University, USA 21, 22, 23, June Fixed Target Physics at CERN : Results and Prospects by J. Engelen / CERN-DG 28, 29, 30 June, 1, 2, July Search for Dark Matter by B. Sadoulet / Univ. of California, Berkeley, USA The lectures are open to all those interested, without application. The abstrac...

  6. Academic Training: 2004 - 2005 ACADEMIC TRAINING PROGRAMME

    CERN Multimedia

    Françoise Benz

    2004-01-01

    1st Term - 01 October to 17 December 2004 REGULAR LECTURE PROGRAMME New Trends in Fusion Research by A. Fasoli, EPFL, Lausanne, CH 11, 12, 13 October Physics at e+e- linear collider by K. Desch, DESY, Hamburg, D 15, 16, 17, 18, 19 November LECTURE SERIES FOR POSTGRADUATE STUDENTS Standard Model by R. Barbieri, CERN-PH-TH 6, 7, 8, 9 10 December The lectures are open to all those interested, without application. The abstract of the lectures, as well as any change to the above information (title, dates, time, place etc) will be published in the CERN Bulletin, the WWW, and by notices before each term and for each series of lectures. ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an 'application for training' form a...

  7. Buoyancy Can-Can

    Science.gov (United States)

    Nelson, Jim; Nelson, Jane Bray

    2015-01-01

    In this paper, a discrepant event is used to initiate a learning cycle lesson to help students develop an understanding of the concept and equation for buoyant force. The data are gathered using readily available equipment and then graphically analyzed using a four-step analysis consistent with the modeling instructional approach. This laboratory…

  8. Experiment Clarifies Buoyancy

    Science.gov (United States)

    Oguz, Ayse; Yurumezoglu, Kemal

    2008-01-01

    This article presents a simple activity using Archimedes' principle that helps students to develop their scientific thinking and also to identify and correct their misconceptions. The exercise consists of linear and reverse processes.

  9. Academic Training: String Theory

    CERN Multimedia

    Françoise Benz

    2005-01-01

    2004-2005 ACADEMIC TRAINING PROGRAMME LECTURE SERIES 6, 7, 8, 9 and 10 June from 11.00 to 12.00 hrs - Auditorium, bldg. 500 on 6, 7, 8 & 10 June, TH Auditorium, bldg. 4, 3rd floor on 9 June String Theory by C. Johnson / Univ. of Southern California, USA ENSEIGNEMENT ACADEMIQUE ACADEMIC TRAINING Françoise Benz 73127 academic.training@cern.ch If you wish to participate in one of the following courses, please discuss with your supervisor and apply electronically directly from the course description pages that can be found on the Web at: http://www.cern.ch/Training/ or fill in an 'application for training' form available from your Divisional Secretariat or from your DTO (Divisional Training Officer). Applications will be accepted in the order of their receipt.

  10. Academic Vocational Training

    DEFF Research Database (Denmark)

    Willert, Søren; Keller, Hanne Dauer; Stegeager, Nikolaj

    2010-01-01

    Danish society puts a high value on education which is traditionally seen as a crucial vehicle for development in all spheres of social and economic life. Large sums are spent on work-related adult learning, an important example being academically based masters programs. Yet, the actual effects o......, with examples, a framework for designing educational programs which can help make academic teaching relevant to production-oriented life in organizations. The paper may be read as a statement from which criteria for evaluating the said masters programs can be generated....... in planning, managing and teaching at masters programs at Aalborg University, Denmark. Programs are carefully designed with a view to strengthening the link between the educational space (the curriculum and academic priorities) and the students’ habitual working environment (the organizations from which...

  11. An academic writing paradox

    DEFF Research Database (Denmark)

    Kampf, Constance Elizabeth

    A key to understanding academic writing for publication lies in the tension between the need for scholars to demonstrate originality, and the need for academic discourse communities to continue using their shared repetoire1 of concepts, vocabulary, and genre structures. This tension can...... be highlighted through a lens which connects Wenger’s conceptualization of knowledge as based in learning, meaning and identity in Communities of Practice, and Nonaka’s SECI model for knowledge conversion which offers a perspective on knowledge creation for innovation. Both innovation and Communities of Practice...... draw on knowledge resources available in organizational and cultural contexts. To explore this tension in different cultural contexts, this paper examines how Ph.d students recognize and use knowledge resources as they learn about and respond to academic publishing. Sites of research include East...

  12. Supporting the academic mission.

    Science.gov (United States)

    Dunnick, N Reed

    2010-03-01

    The mission of an academic radiology department includes not only high-quality patient care, but also the educating of a broad variety of health care professionals, the conducting of research to advance the field, and volunteering service to the medical center and our professional societies. While funding is available for the research and educational aspects, it is insufficient to cover the actual costs. Furthermore, it is becoming increasingly difficult to make up the deficit by using a portion of the clinical revenues. Development and revenues derived from intellectual property are becoming essential to support the academic mission.

  13. Academic Drug Discovery Centres

    DEFF Research Database (Denmark)

    Kirkegaard, Henriette Schultz; Valentin, Finn

    2014-01-01

    Academic drug discovery centres (ADDCs) are seen as one of the solutions to fill the innovation gap in early drug discovery, which has proven challenging for previous organisational models. Prior studies of ADDCs have identified the need to analyse them from the angle of their economic and organi......Academic drug discovery centres (ADDCs) are seen as one of the solutions to fill the innovation gap in early drug discovery, which has proven challenging for previous organisational models. Prior studies of ADDCs have identified the need to analyse them from the angle of their economic...

  14. #IWD2016 Academic Inspiration

    DEFF Research Database (Denmark)

    Meier, Ninna

    2016-01-01

    What academics or books have inspired you in your writing and research, or helped to make sense of the world around you? In this feature essay, Ninna Meier returns to her experience of reading Hannah Arendt as she sought to understand work and how it relates to value production in capitalist...... economies. Meier recounts how Arendt’s book On Revolution (1963) forged connective threads between the ‘smallest parts’ and the ‘largest wholes’ and showed how academic work is never fully relegated to the past, but can return in new iterations across time....

  15. Academic Culture and Campus Culture of Universities

    Science.gov (United States)

    Shen, Xi; Tian, Xianghong

    2012-01-01

    Academic culture of universities mainly consists of academic outlooks, academic spirits, academic ethics and academic environments. Campus culture in a university is characterized by individuality, academic feature, opening, leading, variety and creativity. The academic culture enhances the construction of campus culture. The campus culture…

  16. Carbon Sinks in a Changing Climate: Relative Buoyancy and Sinking Potentials of Various Antarctic Phytoplankton and Ice Algae

    Science.gov (United States)

    Nirmel, S.; Selz, V.

    2016-12-01

    Polar phytoplankton play instrumental roles in global biogeochemical cycles, sometimes serving as massive carbon sinks via the biological pump. In addition to phytoplankton, sea ice supports a significant amount of ice algae, the essential primary producers for the ecosystem in winter and early spring. While sea ice habitat declines on regional scales, the fate of sea ice algae post-ice melt remains relatively unknown, despite its importance in understanding how the biological pump might be affected by sea ice loss. Through a series of settling column experiments on the icebreaker Nathaniel B. Palmer, we aimed to address the question: What controls the fate of the carbon-rich ice algae across the Western Antarctic Peninsula (WAP) during ice melt? We focused on whether species composition affects the sinking potential of ice algal communities. Using FlowCAM imagery, we classified samples collected from the buoyant, neutral, and negatively buoyant portions of the settling columns into genus-level taxonomic classes. We used image parameters and geometric shape equations to calculate the biovolume of each taxonomic group. We further explored relationships between taxa-specific sinking potentials, environmental parameters (temperature and nutrients), and physiological properties of associated algal communities (as described by Fast Rate Repetition fluorometry). Results indicate that colonial Phaeocystis antarctica tends to dominate lower regions of the settling column. Moreover, we observe strong correlations between geographic location and both nutrients and phytoplankton physiology. We found that these three factors are indeed related to taxa-specific buoyancy and sinking indices. An understanding of these relationships sheds more light on the role P. antarctica (a carbon-rich bloom-forming genus) plays in the biological pump; higher sinking rates suggest greater carbon export to depth, while lower sinking rates increase the likelihood of carbon being respired back

  17. Flows around two airfoils performing fling and subsequent translation and translation and subsequent clap

    Science.gov (United States)

    Mao, Sun; Xin, Yu

    2003-04-01

    The aerodynamic forces and flow structures of two airfoils performing “fling and subsequent translation” and “translation and subsequent clap” are studied by numerically solving the Navier-Stokes equations in moving overset grids. These motions are relevant to the flight of very small insects. The Reynolds number, based on the airfoil chord length c and the translation velocity U, is 17. It is shown that: (1) For two airfoils performing fling and subsequent translation, a large lift is generated both in the fling phase and in the early part of the translation phase. During the fling phase, a pair of leading edge vortices of large strength is generated; the generation of the vortex pair in a short period results in a large time rate of change of fluid impulse, which explains the large lift in this period. During the early part of the translation, the two leading edge vortices move with the airfoils; the relative movement of the vortices also results in a large time rate of change of fluid impulse, which explains the large lift in this part of motion. (In the later part of the translation, the vorticity in the vortices is diffused and convected into the wake.) The time averaged lift coefficient is approximately 2.4 times as large as that of a single airfoil performing a similar motion. (2) For two airfoils performing translation and subsequent clap, a large lift is generated in the clap phase. During the clap, a pair of trailing edge vortices of large strength are generated; again, the generation of the vortex pair in a short period (which results in a large time rate of change of fluid impulse) is responsible for the large lift in this period. The time averaged lift coefficient is approximately 1.6 times as large as that of a single airfoil performing a similar motion. (3) When the initial distance between the airfoils (in the case of clap, the final distance between the airfoils) varies from 0.1 to 0.2 c, the lift on an airfoil decreases only slightly but

  18. Productive procrastination: academic procrastination style predicts academic and alcohol outcomes.

    Science.gov (United States)

    Westgate, Erin C; Wormington, Stephanie V; Oleson, Kathryn C; Lindgren, Kristen P

    2017-03-01

    Productive procrastination replaces one adaptive behavior with another adaptive-albeit less important-behavior (e.g., organizing notes instead of studying for an exam). We identified adaptive and maladaptive procrastination styles associated with academic and alcohol outcomes in 1106 college undergraduates. Cluster analysis identified five academic procrastination styles- non-procrastinators , academic productive procrastinators , non-academic productive procrastinators, non-academic procrastinators , and classic procrastinators . Procrastination style differentially predicted alcohol-related problems, cravings, risk of alcohol use disorders, and GPA (all ps procrastination and academic productive procrastination were most adaptive overall; non-academic productive procrastination, non-academic procrastination, and classic procrastination were least adaptive. Productive procrastination differed from other procrastination strategies, and maladaptive procrastination styles may be a useful risk indicator for preventative and intervention efforts.

  19. Buoyancy-Driven Ventilation Generated by the Double-Skin Façade of a High-Rise Building in Tropical Climate: Case Study Bandung, Indonesia

    Directory of Open Access Journals (Sweden)

    Aziiz Akhlish Diinal

    2017-01-01

    Full Text Available High-rise buildings in tropical region is identical to the use of mechanical Air Conditioning in massive scale. Nevertheless, there is an encouragement to high-rise buildings to reduce its energy consumptions, since they consume quite large amount of energy. This challenge can be overcome with various of strategies, one of them, by means of reducing the cooling load of mechanical Air Conditioning in high-rise building. Prospects come from the modern tall building design strategies, for example the use of double-skin façade to give addition of building skin which could provide indoor temperature protection from outside. Double-skin façade system has continued to increase in buildings in a tropical region such as in Indonesia. However, there is another potential of double skin façade, which is the possibility to increase the buoyancy effect in the air gap between the skin and building envelope. The possibility needs to be studied in order to give a proper way in designing double-skin façade of a high-rise building, especially on Bandung-Indonesia tropical climate. This paper explores the potential of double-skin façade in driving the air inside the façade to generate natural ventilation for a high-rise building in Bandung climate condition. Two parameters are used in exploring the buoyancy force, the width of double-skin façade and the temperature of the skin façade. In general, double-skin façade of a high-rise building in tropical climate can generate buoyancy driven ventilation for the building, it relates strongly to the distance between of the double-skin façade and the building envelope.

  20. Measuring faculty retention and success in academic medicine.

    Science.gov (United States)

    Ries, Andrew; Wingard, Deborah; Gamst, Anthony; Larsen, Catherine; Farrell, Elizabeth; Reznik, Vivian

    2012-08-01

    To develop and demonstrate the usefulness of quantitative methods for assessing retention and academic success of junior faculty in academic medicine. The authors created matched sets of participants and nonparticipants in a junior faculty development program based on hire date and academic series for newly hired assistant professors at the University of California, San Diego (UCSD), School of Medicine between 1988 and 2005. They used Kaplan-Meier and Cox proportional hazards survival analyses to characterize the influence of covariates, including gender, ethnicity, and program participation, on retention. They also developed a new method for quantifying academic success based on several measures including (1) leadership and professional activities, (2) honors and awards, (3) research grants, (4) teaching and mentoring/advising activities, and (5) publications. The authors then used these measures to compare matched pairs of participating and nonparticipating faculty who were subsequently promoted and remained at UCSD. Compared with matched nonparticipants, the retention of junior faculty who participated in the faculty development program was significantly higher. Among those who were promoted and remained at UCSD, the academic success of faculty development participants was consistently greater than that of matched nonparticipants. This difference reached statistical significance for leadership and professional activities. Using better quantitative methods for evaluating retention and academic success will improve understanding and research in these areas. In this study, use of such methods indicated that organized junior faculty development programs have positive effects on faculty retention and may facilitate success in academic medicine.

  1. Personal factors that influence deaf college students' academic success.

    Science.gov (United States)

    Albertini, John A; Kelly, Ronald R; Matchett, Mary Karol

    2012-01-01

    Research tells us that academic preparation is key to deaf students' success at college. Yet, that is not the whole story. Many academically prepared students drop out during their first year. This study identified entering deaf college students' personal factors as assessed by their individual responses to both the Noel-Levitz College Student Inventory Form B and the Learning and Study Strategies Inventory, second edition (LASSI). Entering students in 3 successive cohorts (total n =437) participated in this study. Results show that in addition to entry measurements of reading and mathematic skills, personal factors contributed to the academic performance of students in their first quarter in college. The Noel-Levitz provided the comparatively better predictive value of academic performance: Motivation for Academic Study Scale (e.g., desire to finish college). The LASSI also showed statistically significant predictors, the Self-Regulation Component (e.g., time management) and Will Component (e.g., self-discipline), but accounted for relatively less variability in the students' initial grade point averages. For this group of underprepared students, results show that personal factors can play a significant role in academic success. Deaf students' personal factors are discussed as they relate to other first-year college students and to their subsequent academic performance and persistence.

  2. Effects of internal heat generation, thermal radiation and buoyancy force on a boundary layer over a vertical plate with a convective surface boundary condition

    OpenAIRE

    Tasawar Hayat; Awatif A. Hendi; Jacob A. Gbadeyan; Philip O. Olanrewaju

    2011-01-01

    In this paper we analyse the effects of internal heat generation, thermal radiation and buoyancy force on the laminar boundary layer about a vertical plate in a uniform stream of fluid under a convective surface boundary condition. In the analysis, we assumed that the left surface of the plate is in contact with a hot fluid whilst a stream of cold fluid flows steadily over the right surface; the heat source decays exponentially outwards from the surface of the plate. The similarity variable m...

  3. Combined effect of buoyancy and thermo capillarity convections in a low dilatable fluid; L`effet combine de deux convections gravitaire et thermocapillaire dans un fluide faiblement dilatable

    Energy Technology Data Exchange (ETDEWEB)

    Blumenfeld, L.; Soubbaramayer

    1995-12-31

    This work deals with the combined effect of buoyancy and thermo capillarity convections in a low dilatable fluid. A scale law for the Nusselt number in function of the Rayleigh and Marangoni numbers, showing a high non linear coupling between the two convections has been established. This calculation describes a laminar stationary flow. The Navier-Stokes equations system for a law distorted fluid has been resolved in utilizing the Boussinesq approximation. For the case of a turbulent flow, the scale law has been calculated by a correlation method in adjusting experimental data on cerium evaporation by an axisymmetric beam of 5 kw. (O.L.). 10 figs.

  4. Academic staff reward

    African Journals Online (AJOL)

    User

    structures and management systems. As a result, many universities are rethinking their reward strategies to better align them with the new realities in order to improve teaching staff motivation and retention. This study was conducted to identify academic staff reward related problems and to examine the effectiveness of both ...

  5. Academic staff reward

    African Journals Online (AJOL)

    User

    has a major role to play in achieving the objectives of the institution. ... Exceptionally, well motivated academic staff can, with appropriate ... significance attributed to the work. **To perform at their best, most individuals need to have financial or other extrinsic rewards tied to their performance. Rewards. Intrinsic*. Extrinsic**.

  6. The Academic Chairperson's Handbook.

    Science.gov (United States)

    Creswell, John W.; And Others

    This book champions the importance of chairing an academic department (or division) and focuses attention on the strategies "excellent" chairs use in building a positive work environment for faculty and releasing individual faculty potential. The framework is based on human, organizational, and career development; systems theory; and interpersonal…

  7. Unique Academic Skillsets

    Science.gov (United States)

    Jerome, Stephen J.

    2015-01-01

    For the past eighty-two years, Monroe College has been committed to being a national leader in urban and international education. Established in the fall of 2004, the honors program has been transformative for the college, bringing together a wide range of professionals from across disciplines to provide innovative academic offerings. The program…

  8. Confronting Academic Snobbery

    Science.gov (United States)

    Martin, Brian; Sørensen, Majken Jul

    2014-01-01

    Snobbery in academia can involve academics, general staff, students and members of the public, and can be based on degrees, disciplines, cliques and other categories. Though snobbery is seldom treated as a significant issue, it can have damaging effects on morale, research and public image. Strategies against snobbery include avoidance, private…

  9. Academic Nightmares: Predatory Publishing

    Science.gov (United States)

    Van Nuland, Sonya E.; Rogers, Kem A.

    2017-01-01

    Academic researchers who seek to publish their work are confronted daily with a barrage of e-mails from aggressive marketing campaigns that solicit them to publish their research with a specialized, often newly launched, journal. Known as predatory journals, they often promise high editorial and publishing standards, yet their exploitive business…

  10. The academic rat race

    DEFF Research Database (Denmark)

    Landes, Xavier; Andersen, Martin Marchman; Nielsen, Morten Ebbe Juul

    2012-01-01

    : an increased pressure to produce articles (in peer-reviewed journals) has created an unbalanced emphasis on the research criterion at the expense of the latter two. More fatally, this pressure has turned academia into a rat race, leading to a deep change in the fundamental structure of academic behaviour...

  11. An Academic Definitions Test

    Science.gov (United States)

    Isbell, Daniel Richard

    2017-01-01

    L2 vocabulary is commonly conceptualized in terms of a size or depth of one's total lexical knowledge and tested discretely with selection-type items. Concerns exist, however, regarding L2 users' ability to cope with unknown vocabulary, especially in the context of academic reading. This motivated the creation of a test which measures the ability…

  12. Online Academic Integrity

    Science.gov (United States)

    Mastin, David F.; Peszka, Jennifer; Lilly, Deborah R.

    2009-01-01

    Psychology students completed a task with reinforcement for successful performance. We tested academic integrity under randomly assigned conditions of check mark acknowledgment of an honor pledge, typed honor pledge, or no pledge. Across all conditions, 14.1% of students inflated their self-reported performance (i.e., cheated). We found no…

  13. Academic Libraries in Japan

    Science.gov (United States)

    Cullen, Rowena; Nagata, Haruki

    2008-01-01

    Academic libraries in Japan are well resourced by international standards, and support Japan's internationally recognized research capability well, but there are also ways in which they reflect Japan's strong bureaucratic culture. Recent changes to the status of national university libraries have seen a new interest in customer service, and…

  14. Minnesota Academic Standards: Kindergarten

    Science.gov (United States)

    Minnesota Department of Education, 2017

    2017-01-01

    This document contains all of the Minnesota kindergarten academic standards in the content areas of Arts, English Language Arts, Mathematics, Science and Social Studies. For each content area there is a short overview followed by a coding diagram of how the standards are organized and displayed. This document is adapted from the official versions…

  15. Bilingualism and Academic Achievement

    Science.gov (United States)

    Han, Wen-Jui

    2012-01-01

    Using the Early Childhood Longitudinal Study, Kindergarten Cohort, this study examines the role that bilingualism plays in children's academic developmental trajectories during their early school years, with particular attention on the school environment (N = 16,380). Growth-curve results showed that despite starting with lower math scores in…

  16. Correlates of Academic Procrastination.

    Science.gov (United States)

    Milgram, Norman A.; And Others

    1993-01-01

    Investigated concurrent correlates of academic procrastination in Israeli college preparatory students (n=113). Procrastination in one course of study was found to be moderately correlated with procrastination in another but not to procrastination in routine tasks of daily living. Procrastination was weakly related to emotional upset about it and…

  17. Kompetenceprofil for academic developers

    DEFF Research Database (Denmark)

    Troelsen, Rie; Mørcke, Anne Mette

    gerne vil udføre? Vi vil også diskutere hvilke positive og negative konsekvenser en (mulig fælles nordisk) kompetenceprofil kunne få.Referencer:Ansela, M. & Maikkola, M. (2007). ACADEMIC DEVELOPER’S COMPETENCE-BASED DESCRIPTION:Core and basic competences. Retrieved 22/01/15 at http://www.peda-forum.fi/index.php...

  18. Towards Transnational Academic Capitalism

    Science.gov (United States)

    Kauppinen, Ilkka

    2012-01-01

    This paper contributes to current debates on the relationship between globalisation and higher education. The main argument of the paper is that we are currently witnessing transnationalisation of academic capitalism. This argument is illustrated by examining the collaboration between transnational corporations and research universities, and how…

  19. Academic Work and Performance

    Science.gov (United States)

    Gunter, Helen M.

    2012-01-01

    Reading current accounts of higher education demonstrates the flux and damage of rapid neoliberal changes to the type and conduct of academic work. Opening the Times Higher Education magazine on the 28 April 2011 shows articles about cuts in staffing and undergraduate provision in England, concerns about the quality of for-profit higher education…

  20. Why Do Academics Use Academic Social Networking Sites?

    Science.gov (United States)

    Meishar-Tal, Hagit; Pieterse, Efrat

    2017-01-01

    Academic social-networking sites (ASNS) such as Academia.edu and ResearchGate are becoming very popular among academics. These sites allow uploading academic articles, abstracts, and links to published articles; track demand for published articles, and engage in professional interaction. This study investigates the nature of the use and the…

  1. The Effect of Academic Advising on Academic Performance of ...

    African Journals Online (AJOL)

    Although academic advising in Kenyan universities exists, no research has been done to find out how it impacts on students' educational and career goals. This research aimed at establishing the effect of academic advising on academic performance and the influence of year of study and gender on students' tendency to ...

  2. The Specter of Academic Malpractice

    Science.gov (United States)

    Barnes, Carol

    1978-01-01

    The concept of academic malpractice is discussed in terms of student gains in consumerism regarding institutional accountability, and in terms of faculty rights to academic freedom and relationships with administrators. (LBH)

  3. Academic Achievements: Grades versus Duration

    OpenAIRE

    BRUGIAVINI, Agar; CARRARO, Carlo; Kovacic, Matija

    2015-01-01

    This paper investigates the determinants of academic achievements of post-reform undergraduate students of Ca’ Foscari University of Venice. Academic achievements are measured with the students’ grade point averages and time to graduation. The set of independent variables contains information on students’ personal characteristics, prior academic achievements, family background, academic track at university, and several “peer-group” effects. The novelty of this paper is threefold: i) we use a ...

  4. Schooling Background and Academic Academic Achievement of Agricultural Students

    OpenAIRE

    Jayakumar, N.; M. Surudhi

    2016-01-01

    In our society academic achievement is considered as a key criterion to judge one’s total potentiality and capability. Academic achievement is seen as a students’ grade point averages in many academic settings. Academic achievement has become an index of students’ future in this highly competitive world and Agricultural education is no exception.  Hence it becomes necessary to find out the factors that determine better academic performance. In this context the present study had been carried o...

  5. Predicting Academic Entitlement in Undergraduates

    Science.gov (United States)

    Sohr-Preston, Sara; Boswell, Stefanie S.

    2015-01-01

    Academic entitlement (AE) is a common source of frustration for college personnel. This investigation examined predictors (self-concept, academic dishonesty, locus of control, and family functioning) of AE in male and female college students. Academic dishonesty and the interaction between locus of control and family functioning significantly…

  6. Life Stress and Academic Burnout

    Science.gov (United States)

    Lin, Shu-Hui; Huang, Yun-Chen

    2014-01-01

    Stress has been shown to negatively affect learning. Academic burnout is a significant problem associated with poor academic performance. Although there has been increased attention on these two issues, literature on the relationship between students' life stress and burnout is relatively limited. This study surveys academic burnout and life…

  7. Understanding Academic Identity through Metaphor

    Science.gov (United States)

    Billot, Jennie; King, Virginia

    2015-01-01

    Metaphors used by higher education teachers in their narratives of academic life provide insight into aspects of academic identity. Drawing on an international study of leader/follower dynamics, the teachers' narratives reveal how academics interpret their interactions with leaders; the perceived distance between expectations and experience, and…

  8. Academic Freedom Requires Constant Vigilance

    Science.gov (United States)

    Emery, Kim

    2009-01-01

    Traditionally, academic freedom has been understood as an individual right and a negative liberty. As William Tierney and Vincente Lechuga explain, "Academic freedom, although an institutional concept, was vested in the individual professor." The touchstone document on academic freedom, the American Association of University Professor's (AAUP)…

  9. Academic Freedom and Indentured Students

    Science.gov (United States)

    Williams, Jeffrey J.

    2012-01-01

    Discussion of academic freedom usually focuses on faculty, and it usually refers to speech. That is the gist of the 1915 "General Report of the Committee on Academic Freedom and Academic Tenure," appearing in the inaugural AAUP "Bulletin" as a kind of mission statement. Given the conditions of the American system of higher education--decentralized…

  10. Another Discussion about Academic Corruption

    Science.gov (United States)

    Changgeng, Li

    2007-01-01

    Academic corruption is a commonplace matter about which all people are clearly aware. However, people often overlook many hidden or latent manifestations of academic corruption. This article discusses eight of these manifestations: indiscriminate use of the academic team spirit, the proliferation of "word games," deliberate attacks on…

  11. Computer Anxiety, Academic Stress, and Academic Procrastination on College Students

    Directory of Open Access Journals (Sweden)

    Wahyu Rahardjo

    2013-01-01

    Full Text Available Academic procrastination is fairly and commonly found among college students. The lack of understanding in making the best use of computer technology may lead to anxiety in terms of operating computer hence cause postponement in completing course assignments related to computer operation. On the other hand, failure in achieving certain academic targets as expected by parents and/or the students themselves also makes students less focused and leads to tendency of postponing many completions of course assignments. The aim of this research is to investigate contribution of anxiety in operating computer and academic stress toward procrastination on students. As much as 65 students majoring in psychology became participants in this study. The results showed that anxiety in operating computer and academic stress play significant role in influencing academic procrastination among social sciences students. In terms of academic procrastination tendencies, anxiety in operating computer and academic stress, male students have higher percentage than female students.

  12. Body armour and lateral-plate reduction in freshwater three-spined stickleback Gasterosteus aculeatus: adaptations to a different buoyancy regime?

    Science.gov (United States)

    Myhre, F; Klepaker, T

    2009-11-01

    Several factors related to buoyancy were compared between one marine and two freshwater populations of three-spined stickleback Gasterosteus aculeatus. Fish from all three populations had buoyancy near to neutral to the ambient water. This showed that neither marine nor freshwater G. aculeatus used swimming and hydrodynamic lift to prevent sinking. Comparing the swimbladder volumes showed that freshwater completely plated G. aculeatus had a significantly larger swimbladder volume than both completely plated marine and low-plated freshwater G. aculeatus. Furthermore, body tissue density was lower in low-plated G. aculeatus than in the completely plated marine and freshwater fish. The results show that G. aculeatus either reduce tissue density or increase swimbladder volume to adapt to lower water density. Mass measurements of lateral plates and pelvis showed that loss of body armour in low-plated G. aculeatus could explain the tissue density difference between low-plated and completely plated G. aculeatus. This suggests that the common occurrence of plate and armour reduction in freshwater G. aculeatus populations can be an adaptation to a lower water density.

  13. Seasonal trends in adenylate nucleotide content in eggs of recruit and repeat spawning Atlantic cod (Gadus morhua L.) and implications for egg quality and buoyancy

    Science.gov (United States)

    Jung, Kyung-Mi; Svardal, Asbjørn M.; Eide, Torunn; Thorsen, Anders; Kjesbu, Olav Sigurd

    2012-10-01

    Seasonal and ontogenetic variation in egg buoyancy (egg specific gravity; ρ) (n = 63) and nucleotide content (n = 46) were examined for wild-caught Atlantic (Barents Sea) cod (Gadus morhua) held in captivity over two successive spawning seasons, i.e. each female (n = 5) was studied both as recruit and repeat spawner. All eggs were naturally spawned and fertilized, and incubated under optimal condition in flow-through aquaria. Egg diameter and egg dry weight declined steadily during the spawning period, while stage-specific ρ was approximately constant between egg batches (typically around 15 in total). Within each egg batch, i.e. during egg incubation, ρ significantly decreased from the time of gastrulation to before hatching, accompanied by increased contents of ATP and ADP. Altogether, we found that adenylate energy charge (EC) (EC = ([ATP] + 0.5 [ADP]) / ([ATP] + [ADP] + [AMP]) positively affected egg buoyancy (P = 0.013) in concert with egg developmental stage (P cod eggs in the field would show comparably similar trends in ρ and levels of nucleotides.

  14. Bilingualism and academic achievement.

    Science.gov (United States)

    Han, Wen-Jui

    2012-01-01

    Using the Early Childhood Longitudinal Study, Kindergarten Cohort, this study examines the role that bilingualism plays in children's academic developmental trajectories during their early school years, with particular attention on the school environment (N = 16,380). Growth-curve results showed that despite starting with lower math scores in kindergarten, Mixed Bilingual children fully closed the math gap with their White English Monolingual peers by fifth grade. However, because non-English-Dominant Bilinguals and non-English Monolinguals started kindergarten with significantly lower reading and math scores compared to their English Monolingual peers, by fifth grade the former groups still had significantly lower scores. School-level factors explained about one third of the reductions in the differences in children's academic performance. © 2011 The Author. Child Development © 2011 Society for Research in Child Development, Inc.

  15. Participatory academic communities

    DEFF Research Database (Denmark)

    Aaen, Janus Holst; Nørgård, Rikke Toft

    2015-01-01

    Th is article explores community-driven participation in education beyond the institution. By refl ecting on two MA courses at Aarhus University and including educatees’ refl ections in the article, the concept of Participatory Academic Community is developed. Th e article discusses how an evolved...... understanding of participation in edu-cation can move educatees’ learning beyond institutions through focusing on educatees as researchers, participat-ing in society, building a research community and obtaining academic citizenship. Further, the article discusses how a value-based, vision-driven approach...... to education and the use of ICT might nurture participation and construction of community within education. Th e article is genuinely transdisciplinary in its approach, apply-ing diff erent theoretical lenses to obtain a more holistic view on participation in education. Th e article creates a prismatic lens...

  16. From ERPs to academics.

    Science.gov (United States)

    Hillman, Charles H; Pontifex, Matthew B; Motl, Robert W; O'Leary, Kevin C; Johnson, Christopher R; Scudder, Mark R; Raine, Lauren B; Castelli, Darla M

    2012-02-15

    Standardized tests have been used to forecast scholastic success of school-age children, and have been related to intelligence, working memory, and inhibition using neuropsychological tests. However, ERP correlates of standardized achievement have not been reported. Thus, the relationship between academic achievement and the P3 component was assessed in a sample of 105 children during performance on a Go/NoGo task. The Wide Range Achievement Test - 3rd edition was administered to assess aptitude in reading, spelling, and arithmetic. Regression analyses indicated an independent contribution of P3 amplitude to reading and arithmetic achievement beyond the variance accounted for by IQ and school grade. No such relationship was observed for spelling. These data suggest that the P3, which reflects attentional processes involved in stimulus evaluation and inhibitory control may be a biomarker for academic achievement during childhood. Copyright © 2011 Elsevier Ltd. All rights reserved.

  17. Academic dishonesty among nursing students.

    Science.gov (United States)

    Krueger, Linda

    2014-02-01

    This quantitative study identified sociodemographic and situational conditions that affected 336 nursing students' engagement in academic dishonesty, their attitudes regarding various forms of academic dishonesty, and the prevalence of academic dishonesty in which they engaged and witnessed. More than half of the participants reported cheating in the classroom and in the clinical settings. A positive relationship was found between the frequency of cheating in classroom and clinical settings. Results revealed differences in frequency of engagement in and attitudes toward academic dishonesty by gender, semester in the program, and ethnicity. Relationships were also found among peer behavior, personal beliefs and values, and frequency of engaging in academic dishonesty. Copyright 2014, SLACK Incorporated.

  18. Academic Manager or Managed Academic? Academic Identity Schisms in Higher Education

    Science.gov (United States)

    Winter, Richard

    2009-01-01

    The relationship between values and academic identity has received scant attention in the higher education literature with some notable exceptions (Churchman, 2006; Harley, 2002; Henkel, 2005). This paper contends that the perceived need to align all academics around corporate values and goals has given rise to academic identity schisms in higher…

  19. The "Secrets" of Chinese Students' Academic Success: Academic Resilience among Students from Highly Competitive Academic Environments

    Science.gov (United States)

    Li, Haibin

    2017-01-01

    Given Chinese students often perform well academically despite the challenges of their competitive academic environments, it is important to explore what enables the academic resilience of these students. Moreover, because the extant resilience literature is biased towards Western accounts of resilience, it is crucial that non-Western perspectives…

  20. Gender Differences in the Relationship between Academic Procrastination, Satisfaction with Academic Life and Academic Performance

    Science.gov (United States)

    Balkis, Murat; Duru, Erdinç

    2017-01-01

    Introduction: Procrastination has become one of the most researched topics due its adverse effects on the both general and student population in social sciences. The general tendency toward delaying academic tasks has been conceptualized as academic procrastination in academic setting. It is a prevalent issue among students and a numerous students…

  1. Plagiarism in Academic Texts

    Directory of Open Access Journals (Sweden)

    Marta Eugenia Rojas-Porras

    2012-08-01

    Full Text Available The ethical and social responsibility of citing the sources in a scientific or artistic work is undeniable. This paper explores, in a preliminary way, academic plagiarism in its various forms. It includes findings based on a forensic analysis. The purpose of this paper is to raise awareness on the importance of considering these details when writing and publishing a text. Hopefully, this analysis may put the issue under discussion.

  2. Declaration of Academic Freedom

    OpenAIRE

    ÇETİNSAYA, Gökhan

    2014-01-01

    1. Universities are the institutions where all the opinions, various truth claims as well as social and political problems are discussed in a liberal and civilized way and the complicated problems are expressed clearly without any oppression and prevention. 2. Academic freedom includes first and foremost the right of freedom of research and thus freedom of using the essential knowledge methods, the right of possessing the necessary tools and conditions required for the research and the rig...

  3. Identifying potential academic leaders

    Science.gov (United States)

    White, David; Krueger, Paul; Meaney, Christopher; Antao, Viola; Kim, Florence; Kwong, Jeffrey C.

    2016-01-01

    Objective To identify variables associated with willingness to undertake leadership roles among academic family medicine faculty. Design Web-based survey. Bivariate and multivariable analyses (logistic regression) were used to identify variables associated with willingness to undertake leadership roles. Setting Department of Family and Community Medicine at the University of Toronto in Ontario. Participants A total of 687 faculty members. Main outcome measures Variables related to respondents’ willingness to take on various academic leadership roles. Results Of all 1029 faculty members invited to participate in the survey, 687 (66.8%) members responded. Of the respondents, 596 (86.8%) indicated their level of willingness to take on various academic leadership roles. Multivariable analysis revealed that the predictors associated with willingness to take on leadership roles were as follows: pursuit of professional development opportunities (odds ratio [OR] 3.79, 95% CI 2.29 to 6.27); currently holding at least 1 leadership role (OR 5.37, 95% CI 3.38 to 8.53); a history of leadership training (OR 1.86, 95% CI 1.25 to 2.78); the perception that mentorship is important for one’s current role (OR 2.25, 95% CI 1.40 to 3.60); and younger age (OR 0.97, 95% CI 0.95 to 0.99). Conclusion Willingness to undertake new or additional leadership roles was associated with 2 variables related to leadership experiences, 2 variables related to perceptions of mentorship and professional development, and 1 demographic variable (younger age). Interventions that support opportunities in these areas might expand the pool and strengthen the academic leadership potential of faculty members. PMID:27331226

  4. Students’ academic self perception

    OpenAIRE

    Chevalier, Arnaud; Gibbons, Steve; Thorpe, Andy; Hoskins, Sherria

    2007-01-01

    Participation rates in higher education differ persistently between some groups in society. Using two British datasets we investigate whether this gap is rooted in students' misperception of their own and other's ability, thereby increasing the expected costs to studying. Among high school pupils, we find that pupils with a more positive view of their academic abilities are more likely to expect to continue to higher education even after controlling for observable measures of ability and s...

  5. Leisure-Time Physical Activity and Academic Performance: Cross-Lagged Associations from Adolescence to Young Adulthood

    Science.gov (United States)

    Aaltonen, Sari; Latvala, Antti; Rose, Richard J.; Kujala, Urho M.; Kaprio, Jaakko; Silventoinen, Karri

    2016-01-01

    Physical activity and academic performance are positively associated, but the direction of the association is poorly understood. This longitudinal study examined the direction and magnitude of the associations between leisure-time physical activity and academic performance throughout adolescence and young adulthood. The participants were Finnish twins (from 2,859 to 4,190 individuals/study wave) and their families. In a cross-lagged path model, higher academic performance at ages 12, 14 and 17 predicted higher leisure-time physical activity at subsequent time-points (standardized path coefficient at age 14: 0.07 (p academic performance. A cross-lagged model of co-twin differences suggested that academic performance and subsequent physical activity were not associated due to the environmental factors shared by co-twins. Our findings suggest that better academic performance in adolescence modestly predicts more frequent leisure-time physical activity in late adolescence and young adulthood. PMID:27976699

  6. Leisure-Time Physical Activity and Academic Performance: Cross-Lagged Associations from Adolescence to Young Adulthood.

    Science.gov (United States)

    Aaltonen, Sari; Latvala, Antti; Rose, Richard J; Kujala, Urho M; Kaprio, Jaakko; Silventoinen, Karri

    2016-12-15

    Physical activity and academic performance are positively associated, but the direction of the association is poorly understood. This longitudinal study examined the direction and magnitude of the associations between leisure-time physical activity and academic performance throughout adolescence and young adulthood. The participants were Finnish twins (from 2,859 to 4,190 individuals/study wave) and their families. In a cross-lagged path model, higher academic performance at ages 12, 14 and 17 predicted higher leisure-time physical activity at subsequent time-points (standardized path coefficient at age 14: 0.07 (p academic performance. A cross-lagged model of co-twin differences suggested that academic performance and subsequent physical activity were not associated due to the environmental factors shared by co-twins. Our findings suggest that better academic performance in adolescence modestly predicts more frequent leisure-time physical activity in late adolescence and young adulthood.

  7. Association between academic and non-academic variables and academic success of diploma nursing students in Pakistan.

    Science.gov (United States)

    Ali, Parveen Azam; Naylor, Paul B

    2010-02-01

    This paper reports findings of an exploratory study conducted to determine an association between academic and non-academic factors and academic success of nursing diploma students in a province of Pakistan. Data were collected from the academic records of a cohort of 628 students. Multiple linear regression was used to identify the predictive association between certain academic and non-academic factors and academic success of the students. Regression models for each of three years were developed. Results indicated academic factors including preadmission qualifications, previous academic performance, academic performance in year one, academic performance in year two and type of school are significantly associated with the academic success of the students. Among non-academic factors, gender and place of domicile were found to be significantly associated with the academic success of the students. Copyright 2009 Elsevier Ltd. All rights reserved.

  8. The Role of Personal Best (PB) and Dichotomous Achievement Goals in Students' Academic Motivation and Engagement: A Longitudinal Investigation

    Science.gov (United States)

    Martin, Andrew J.; Elliot, Andrew J.

    2016-01-01

    This study assessed the role of prior personal best goals in predicting subsequent academic motivation and engagement. A total of 1160 high school students participated in a longitudinal survey study exploring the extent to which personal best and mastery and performance (dichotomous) achievement goals predict students' academic motivation and…

  9. Academic Motivations and Academic Self-Efficacy of Nursing Students

    Directory of Open Access Journals (Sweden)

    Gamze Sarikoc

    2017-01-01

    Full Text Available Aim: Academic motivation and academic self-efficacy play important roles in the learning process. They increase academic achievement and the attainment of educational goals, thus providing opportunities in the training of qualified nurses. This study was conducted to determine nursing students%u2019 academic motivation and academic self-efficacy levels. Material and Method: This is a descriptive study. A total of 346 students who are attending a nursing school as either a first, second, third, or fourth year student have been accepted in the study. The Academic Motivation Scale and Academic Self-Efficacy Scale were used to collect data. Results: The total score of the participants for extrinsic motivation was 66.52 ± 10.29, and for intrinsic motivation 64.60 ± 10.75. It was observed that freshmen have a higher level of intrinsic motivation than the sophomores and the seniors; and the extrinsic motivation of the juniors is less than all the other classes. It was determined that there is a positive self-efficacy relationship between the intrinsic motivation and extrinsic motivation levels of the students. Discussion: In the study we determined that there is a difference between the classes in terms of academic motivation. For this reason psychoeducational interventions may be helpful in improving the academic motivation of the students, thus producing nurses who are confident and willing to learn.

  10. Schooling Background and Academic Academic Achievement of Agricultural Students

    Directory of Open Access Journals (Sweden)

    N. Jayakumar

    2016-05-01

    Full Text Available In our society academic achievement is considered as a key criterion to judge one’s total potentiality and capability. Academic achievement is seen as a students’ grade point averages in many academic settings. Academic achievement has become an index of students’ future in this highly competitive world and Agricultural education is no exception.  Hence it becomes necessary to find out the factors that determine better academic performance. In this context the present study had been carried out to find out the possible relationship between schooling background and academic achievement of agriculture students. The students admitted in Adhiparasakthi Agricultural College, Kalavai, Vellore between 1999 and 2009 formed the subjects of the study. Findings of the study revealed that determinants like gender, type of school and stream of education had a significant role in the academic achievement of the students. Medium of instruction in HSC did influence the academic achievement but not significantly. It was also found that students who performed well in their HSC did perform well in their undergraduate programme also. This confirms that previous educational outcomes are the most important indicators of student’s future achievement and schooling background has a significant role in academic achievement of students.

  11. Tracking maximum ascending subsequences in sequences of partially ordered data

    NARCIS (Netherlands)

    Kloks, Ton; Tan, Richard B.; van Leeuwen, J.|info:eu-repo/dai/nl/068413025

    We consider scenarios in which long sequences of data are analyzed and subsequences must be traced that are monotone and maximum, according to some measure. A classical example is the online Longest Increasing Subsequence Problem for numeric and alphanumeric data. We extend the problem in two ways:

  12. Morbidity and risk of subsequent diagnosis of HIV

    DEFF Research Database (Denmark)

    Søgaard, Ole S; Lohse, Nicolai; Østergaard, Lars Jørgen

    2012-01-01

    Early identification of persons with undiagnosed HIV infection is an important health care issue. We examined associations between diseases diagnosed in hospitals and risk of subsequent HIV diagnosis.......Early identification of persons with undiagnosed HIV infection is an important health care issue. We examined associations between diseases diagnosed in hospitals and risk of subsequent HIV diagnosis....

  13. 38 CFR 36.4324 - Guaranty claims; subsequent accounting.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 2 2010-07-01 2010-07-01 false Guaranty claims; subsequent accounting. 36.4324 Section 36.4324 Pensions, Bonuses, and Veterans' Relief DEPARTMENT OF VETERANS... § 36.4324 Guaranty claims; subsequent accounting. (a) Subject to the limitation that the total amounts...

  14. Recurrent miscarriage and antiphospholipid antibodies: prognosis of subsequent pregnancy.

    NARCIS (Netherlands)

    Cohn, D.M.; Goddijn, M.; Middeldorp, S.; Korevaar, J.C.; Dawood, F.; Farquharson, R.G.

    2010-01-01

    Background: Although women with antiphospholipid antibodies (APLAs) are at increased risk of recurrent miscarriage, the outcome of a subsequent pregnancy is not clearly elucidated. Objectives: To assess the pregnancy outcome of a subsequent pregnancy in women with APLAs and compare this outcome with

  15. Benchmarking Academic Anatomic Pathologists

    Directory of Open Access Journals (Sweden)

    Barbara S. Ducatman MD

    2016-10-01

    Full Text Available The most common benchmarks for faculty productivity are derived from Medical Group Management Association (MGMA or Vizient-AAMC Faculty Practice Solutions Center ® (FPSC databases. The Association of Pathology Chairs has also collected similar survey data for several years. We examined the Association of Pathology Chairs annual faculty productivity data and compared it with MGMA and FPSC data to understand the value, inherent flaws, and limitations of benchmarking data. We hypothesized that the variability in calculated faculty productivity is due to the type of practice model and clinical effort allocation. Data from the Association of Pathology Chairs survey on 629 surgical pathologists and/or anatomic pathologists from 51 programs were analyzed. From review of service assignments, we were able to assign each pathologist to a specific practice model: general anatomic pathologists/surgical pathologists, 1 or more subspecialties, or a hybrid of the 2 models. There were statistically significant differences among academic ranks and practice types. When we analyzed our data using each organization’s methods, the median results for the anatomic pathologists/surgical pathologists general practice model compared to MGMA and FPSC results for anatomic and/or surgical pathology were quite close. Both MGMA and FPSC data exclude a significant proportion of academic pathologists with clinical duties. We used the more inclusive FPSC definition of clinical “full-time faculty” (0.60 clinical full-time equivalent and above. The correlation between clinical full-time equivalent effort allocation, annual days on service, and annual work relative value unit productivity was poor. This study demonstrates that effort allocations are variable across academic departments of pathology and do not correlate well with either work relative value unit effort or reported days on service. Although the Association of Pathology Chairs–reported median work relative

  16. Benchmarking Academic Anatomic Pathologists

    Science.gov (United States)

    Parslow, Tristram

    2016-01-01

    The most common benchmarks for faculty productivity are derived from Medical Group Management Association (MGMA) or Vizient-AAMC Faculty Practice Solutions Center® (FPSC) databases. The Association of Pathology Chairs has also collected similar survey data for several years. We examined the Association of Pathology Chairs annual faculty productivity data and compared it with MGMA and FPSC data to understand the value, inherent flaws, and limitations of benchmarking data. We hypothesized that the variability in calculated faculty productivity is due to the type of practice model and clinical effort allocation. Data from the Association of Pathology Chairs survey on 629 surgical pathologists and/or anatomic pathologists from 51 programs were analyzed. From review of service assignments, we were able to assign each pathologist to a specific practice model: general anatomic pathologists/surgical pathologists, 1 or more subspecialties, or a hybrid of the 2 models. There were statistically significant differences among academic ranks and practice types. When we analyzed our data using each organization’s methods, the median results for the anatomic pathologists/surgical pathologists general practice model compared to MGMA and FPSC results for anatomic and/or surgical pathology were quite close. Both MGMA and FPSC data exclude a significant proportion of academic pathologists with clinical duties. We used the more inclusive FPSC definition of clinical “full-time faculty” (0.60 clinical full-time equivalent and above). The correlation between clinical full-time equivalent effort allocation, annual days on service, and annual work relative value unit productivity was poor. This study demonstrates that effort allocations are variable across academic departments of pathology and do not correlate well with either work relative value unit effort or reported days on service. Although the Association of Pathology Chairs–reported median work relative value unit

  17. Pedagogy and Academic Success in Prelicensure Nursing Education.

    Science.gov (United States)

    Murray, Teri A

    2016-01-01

    The purpose of this article is to provide a brief description of the New Careers in Nursing (NCIN) program; highlight the features of the NCIN Preentry Immersion program designed to help students achieve academic success; introduce two NCIN innovation teaching projects that used active learning strategies to foster student engagement; and conduct an integrative review on the pedagogies used to foster academic success in nursing education. The integrative review revealed that interactive pedagogies fostered student engagement and increased the students' knowledge acquisition, competence, confidence, and satisfaction. Significant variations in the methodological rigor for the studies included in this review were noted in addition to nebulousness between nursing education research and evaluation. The review validated the need for more rigorous research in nursing education to improve the students' academic experience and subsequent success of all nursing students, including those from underrepresented or disadvantaged backgrounds, enrolled in prelicensure nursing education programs. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Revisiting the relationship between attributional style and academic performance

    Science.gov (United States)

    2015-01-01

    Abstract Previous research into the relationship between attributions and academic performance has produced contradictory findings that have not been resolved. The present research examines the role of specific dimensions of attributional style in predicting subsequent academic performance in a sample of pupils (N = 979) from both high‐ and low‐achieving schools. Hierarchical regression and moderation analyses indicate that internal, stable, and global, attributional styles for positive events predict higher levels of academic performance. Global attributions for negative events were related to poorer performance across all schools. Stable attributions for negative events were related to higher levels of performance in high‐achieving schools but not in low‐achieving schools. Higher levels of internality for negative events were associated with higher performance only in low achieving schools. PMID:27594711

  19. Peer effects in academic performance

    OpenAIRE

    Hayashi, Ryohei

    2016-01-01

    This paper deals with the data of dormitory students in National Institute of Technology, Kagoshima College to demonstrate the existence of peer effects in academic performance. The data have unique advantages to avoid the difficulties of the self-selection problem and reflection problem. The data shows freshmen's academic performance and previous year's junior high school records, and roommate's previous year's academic performance for using an instrumental variable method. The results of my...

  20. Academic Freedom in Higher Education

    Directory of Open Access Journals (Sweden)

    Tokay GEDİKOĞLU

    2013-12-01

    Full Text Available In this study, the concept ‘academic freedom’ is discussed, its implications and value for the academics, institutions of higher education, and the society are focused, and a few suggestions for the Turkish higher education are made. Academic freedom is defined as the freedom of the academic staff to look for and to find the truth in their scientific field, to publish the findings, and to teach these findings to their students without any external intervention. The concept has gained a further definition with inclusion of research activities into academic freedom as part of the reform attempts started in the German higher education in the 19th century. Therefore, academic freedom is at the very core of the missions of the institutions of higher education; that is, teaching-learning and research. On the point of academic staff and their academic activities of the academic freedom, the subjects such as the aim of the course, choosing the teaching materials and textbooks, the lecturer, and the criteria for the measurement and evaluation of the course take place. And he point of research covers the aim of the study, academicians can’t be imposed the involve in an academic and artistic studies that conflict their values and beliefs; researchers should comply with codes of ethical principles and practices during the process of researching; and research outputs should be reported accurately and honestly without any misleading manipulation. Academic freedom does not provide any exemption from accountability in academic activities of the faculty, nor does it provide any right to act against the well-being of the society, current laws and regulations, and codes of ethical principles and practices.

  1. Combined effect of buoyancy force and Navier slip on MHD flow of a nanofluid over a convectively heated vertical porous plate.

    Science.gov (United States)

    Mutuku-Njane, Winifred Nduku; Makinde, Oluwole Daniel

    2013-01-01

    We examine the effect of magnetic field on boundary layer flow of an incompressible electrically conducting water-based nanofluids past a convectively heated vertical porous plate with Navier slip boundary condition. A suitable similarity transformation is employed to reduce the governing partial differential equations into nonlinear ordinary differential equations, which are solved numerically by employing fourth-order Runge-Kutta with a shooting technique. Three different water-based nanofluids containing copper (Cu), aluminium oxide (Al2O3), and titanium dioxide (TiO2) are taken into consideration. Graphical results are presented and discussed quantitatively with respect to the influence of pertinent parameters, such as solid volume fraction of nanoparticles (φ), magnetic field parameter (Ha), buoyancy effect (Gr), Eckert number (Ec), suction/injection parameter (f w ), Biot number (Bi), and slip parameter ( β ), on the dimensionless velocity, temperature, skin friction coefficient, and heat transfer rate.

  2. Numerical investigation of combined buoyancy-thermocapillary convection and entropy generation in 3D cavity filled with Al2O3 nanofluid

    Directory of Open Access Journals (Sweden)

    Lioua Kolsi

    2017-03-01

    Full Text Available Heat transfer, fluid flow and entropy generation due to combined buoyancy and thermocapillary forces in a 3D differentially heated enclosure containing Al2O3 nanofluid are carried out for different Marangoni numbers and different nanoparticles concentrations. The vector potential-vorticity formalism and the finite volume method are used respectively to formulate and to solve the governing equations and calculations were performed for Marangoni number from −103 to 103, volume fraction of nanoparticles from 0 to 0.2 and for a fixed Rayleigh number at 105. An intensification of the flow and an increase in heat transfer and of total entropy generation occur with the increase in nanoparticles volume fraction for all Marangoni numbers.

  3. Some Exact Solutions of Boundary Layer Flows along a Vertical Plate with Buoyancy Forces Combined with Lorentz Forces under Uniform Suction

    Directory of Open Access Journals (Sweden)

    Asterios Pantokratoras

    2008-01-01

    Full Text Available Exact analytical solutions of boundary layer flows along a vertical porous plate with uniform suction are derived and presented in this paper. The solutions concern the Blasius, Sakiadis, and Blasius-Sakiadis flows with buoyancy forces combined with either MHD Lorentz or EMHD Lorentz forces. In addition, some exact solutions are presented specifically for water in the temperature range of 0∘C≤≤8∘C, where water density is nearly parabolic. Except for their use as benchmarking means for testing the numerical solution of the Navier-Stokes equations, the presented exact solutions with EMHD forces have use in flow separation control in aeronautics and hydronautics, whereas the MHD results have applications in process metallurgy and fusion technology. These analytical solutions are valid for flows with strong suction.

  4. Elephants in academic medicine.

    Science.gov (United States)

    Souba, Wiley; Way, David; Lucey, Catherine; Sedmak, Daniel; Notestine, Mark

    2011-12-01

    To study the types, causes, and consequences of academic health center (AHC) "elephants," which the authors define as obvious problems that impair performance but which the community collectively does not discuss or confront. Between April and June 2010, the authors polled all the chairs of departments of medicine and of surgery at the then 127 U.S. medical-degree-granting medical schools, using a combination of Web and postal surveys. Of the 254 chairs polled, 139 (55%) responded. Of 137 chairs, 95 (69%) reported that elephants in their organizations were common or widespread. The most common elephant reported was misalignment between goals and available resources. Chairs felt that the main reason faculty are silent is their perception that speaking up will be ignored and that the consequences of elephants include impaired organizational learning, flawed information resulting in poor decisions, and negative effects on morale. Chairs felt elephants were more problematic among deans and hospital leaders than in their own departments. Of 139 chairs, 87 (63%) said that elephants were discussed inappropriately, and of 137 chairs, 92 (67%) believed that creating a culture that dealt with elephants would be difficult. Chairs felt the best antidote for elephants was having senior leaders lead by example, yet 77 of 139 (55%) reported that the actions of top leaders fed, rather than dispelled, elephants. AHC elephants are prevalent and detrimental to learning, organizational decision making, and morale, yet the academic medicine community, particularly its leadership, insufficiently confronts them.

  5. Peer relationships and academic achievement

    Directory of Open Access Journals (Sweden)

    Krnjajić Stevan B.

    2002-01-01

    Full Text Available After their childhood, when children begin to establish more intensive social contacts outside family, first of all, in school setting, their behavior i.e. their social, intellectual, moral and emotional development is more strongly affected by their peers. Consequently, the quality of peer relationships considerably affects the process of adaptation and academic achievement and their motivational and emotional attitude towards school respectively. Empirical findings showed that there is bi-directional influence between peer relationships and academic achievement. In other words, the quality of peer relationships affects academic achievement, and conversely, academic achievement affects the quality of peer relationships. For example, socially accepted children exhibiting prosocial, cooperative and responsible forms of behavior in school most frequently have high academic achievement. On the other hand, children rejected by their peers often have lower academic achievement and are a risk group tending to delinquency, absenteeism and drop out of school. Those behavioral and interpersonal forms of competence are frequently more reliable predictors of academic achievement than intellectual abilities are. Considering the fact that various patterns of peer interaction differently exert influence on students' academic behavior, the paper analyzed effects of (a social competence, (b social acceptance/rejection, (c child's friendships and (d prosocial behavior on academic achievement.

  6. Impact of alcohol consumption on academic performance of university students

    OpenAIRE

    Tyburcová, Iva

    2012-01-01

    This bachelor thesis examines the impact of alcohol consumption on academic performance of university students. This impact was examined on students studying economics at University of Economics, Prague. Dataset was obtained from students by questionnaire survey and was subsequently supplemented by official data from the university's database. Based on the theoretical model an econometric model which examines the relationship was build. The results showed that intensity of consumption of alco...

  7. The effects of lateral density gradients, slopes and buoyancy on channel flow: 1D analytical solutions and applications to the SE Canadian Cordillera

    Science.gov (United States)

    Gervais, Félix; Ranalli, Giorgio

    2017-08-01

    We present 1D analytical solutions for channel flow in orogens driven by various types of pressure gradients. Our calculations demonstrate that lateral density gradients in the upper crust, such as would occur across a suture zone separating arc rocks from pericratonic sediments provide a driving force for Poiseuille flow as large as topographic gradients observed in modern mountain belts. For cases for which the gradients are external (topographic and lateral density gradients) and internal (e.g. partial melting of channel material) to the channel, inclination decreases and increases the Poiseuille component of the average flow-velocity within the channel by the cosine and sine of the slope, respectively. The magnitude of the pressure gradient consequent upon the buoyancy generated by partial melting of metapelites in a channel with a 30° slope, such as would occur above an underthrusting basement ramp, is similar to that of topographic or lateral density gradients. Channel flow up a ramp could thus constitute an important exhumation mechanism in large hot orogens. Our calculations indicate that mid-crustal channel flow was a highly likely process in the Late Cretaceous-Paleocene setting of the southeastern Canadian Cordillera. The flow was first driven by the lateral density contrast between pericratonic sediments and the arc-related Intermontane terrane, then by combined effect of topographic gradient and melt-induced buoyancy of the Lower Selkirk Allochthon (part of the Shuswap Complex). Flow up the underthrusting basement ramp resulted in exhumation from mid- to upper-crustal levels. Channel flow then migrated downward to involve basement and overlying cover sequence rocks. Our results indicate that syn-convergent channel flow was a viable and very likely process in the southeastern Canadian Cordillera.

  8. The Effect of Academic Advising on Academic Performance of ...

    African Journals Online (AJOL)

    User

    ISSN 2070--0083 (Online). DOI: http://dx.doi.org/10.4314/afrrev.v5i5.26. The Effect of Academic Advising on Academic Performance of University Students in Kenyan Universities. (Pp. 332-345). Muola, J. M. - South Eastern University College, School of Education. P.O. BOX 170 – 90200, KITUI, Kenya. Tel. +254 721 228 621.

  9. The Effect of Academic Advising on Academic Performance of ...

    African Journals Online (AJOL)

    User

    The availability of exemplary, caring role models is important for all students, but may be especially critical to the retention and success of college students who do not have role models at home. Research on mentoring indicates that it. The Effect of Academic Advising on Academic Performance of University Students.

  10. Performance samples on academic tasks : improving prediction of academic performance

    NARCIS (Netherlands)

    Tanilon, Jenny

    2011-01-01

    This thesis is about the development and validation of a performance-based test, labeled as Performance Samples on academic tasks in Education and Child Studies (PSEd). PSEd is designed to identify students who are most able to perform the academic tasks involved in an Education and Child Studies

  11. The "Second Academic Revolution": Interpretations of Academic Entrepreneurship

    Science.gov (United States)

    Zheng, Peijun

    2010-01-01

    The number and scope of faculty and institutions involved in academic entrepreneurship continues to expand, and this has significant implications for universities, involving potentially wonderful opportunities but also dire risks. This paper looks beyond academic capitalism, a theory that currently dominates the study of higher education, by…

  12. Discipline-specific versus generic academic literacy intervention for ...

    African Journals Online (AJOL)

    Keywords: Academic literacy, discipline-specific AL, generic AL, academic language support, academic language proficiency, English for Specific Purposes, English for Academic Purposes, academic writing, academic reading, Contentbased Instruction, Language Across the Curriculum, Writing Across the Curriculum, ...

  13. Are They Using My Feedback? The Extent of Students' Feedback Use Has a Large Impact on Subsequent Academic Performance

    Science.gov (United States)

    Zimbardi, Kirsten; Colthorpe, Kay; Dekker, Andrew; Engstrom, Craig; Bugarcic, Andrea; Worthy, Peter; Victor, Ruban; Chunduri, Prasad; Lluka, Lesley; Long, Phil

    2017-01-01

    Feedback is known to have a large influence on student learning gains, and the emergence of online tools has greatly enhanced the opportunity for delivering timely, expressive, digital feedback and for investigating its learning impacts. However, to date there have been no large quantitative investigations of the feedback provided by large teams…

  14. An intercalated BSc degree is associated with higher marks in subsequent medical school examinations.

    Science.gov (United States)

    Cleland, Jennifer A; Milne, Andrew; Sinclair, Hazel; Lee, Amanda J

    2009-05-19

    To compare medical students on a modern MBChB programme who did an optional intercalated degree with their peers who did not intercalate; in particular, to monitor performance in subsequent undergraduate degree exams. This was a retrospective, observational study of anonymised databases of medical student assessment outcomes. Data were accessed for graduates, University of Aberdeen Medical School, Scotland, UK, from the years 2003 to 2007 (n = 861). The main outcome measure was marks for summative degree assessments taken after intercalating. Of 861 medical students, 154 (17.9%) students did an intercalated degree. After adjustment for cohort, maturity, gender and baseline (3rd year) performance in matching exam type, having done an IC degree was significantly associated with attaining high (18-20) common assessment scale (CAS) marks in three of the six degree assessments occurring after the IC students rejoined the course: the 4th year written exam (p < 0.001), 4th year OSCE (p = 0.001) and the 5th year Elective project (p = 0.010). Intercalating was associated with improved performance in Years 4 and 5 of the MBChB. This improved performance will further contribute to higher academic ranking for Foundation Year posts. Long-term follow-up is required to identify if doing an optional intercalated degree as part of a modern medical degree is associated with following a career in academic medicine.

  15. Academic dishonesty and attitudes towards academic dishonest acts: support for cognitive dissonance theory.

    Science.gov (United States)

    Storch, Eric A; Storch, Jason B

    2003-02-01

    The present study examined the relation between self-reported academic dishonesty and attitudes towards dishonest academic behaviors in 244 college students. Analysis suggested that self-reported academic dishonesty and approval of academic dishonest behaviors were positively correlated.

  16. Twin birth changes DNA methylation of subsequent siblings

    National Research Council Canada - National Science Library

    Shuai Li; Eunae Kim; Ee Ming Wong; Ji-Hoon Eric Joo; Tuong L Nguyen; Jennifer Stone; Yun-Mi Song; Louisa B Flander; Richard Saffery; Graham G Giles; Melissa C Southey; Joohon Sung; John L Hopper

    2017-01-01

    We asked if twin birth influences the DNA methylation of subsequent siblings. We measured whole blood methylation using the HumanMethylation450 array for siblings from two twin and family studies in Australia and Korea...

  17. Associations between mental disorders and subsequent onset of hypertension

    NARCIS (Netherlands)

    Stein, Dan J.; Aguilar-Gaxiola, Sergio; Alonso, Jordi; Bruffaerts, Ronny; de Jonge, Peter; Liu, Zharoui; Caldas-de-Almeida, Jose Miguel; O'Neill, Siobhan; Viana, Maria Carmen; Al-Hamzawi, Ali Obaid; Angermeyer, Mattias C.; Benjet, Corina; de Graaf, Ron; Ferry, Finola; Kovess-Masfety, Viviane; Levinson, Daphna; de Girolamo, Giovanni; Florescu, Silvia; Hu, Chiyi; Kawakami, Norito; Haro, Josep Maria; Piazza, Marina; Posada-Villa, Jose; Wojtyniak, Bogdan J.; Xavier, Miguel; Lim, Carmen C. W.; Kessler, Ronald C.; Scott, Kate M.

    2014-01-01

    Background: Previous work has suggested significant associations between various psychological symptoms (e. g., depression, anxiety, anger, alcohol abuse) and hypertension. However, the presence and extent of associations between common mental disorders and subsequent adult onset of hypertension

  18. Theta and Gamma Oscillations during Encoding Predict Subsequent Recall

    National Research Council Canada - National Science Library

    Sederberg, Per B; Kahana, Michael J; Howard, Marc W; Donner, Elizabeth J; Madsen, Joseph R

    2003-01-01

    ... to 64 Hz as participants studied lists of common nouns. Significant increases in oscillatory power during encoding predicted subsequent recall, with this effect predominantly in the 4-8 Hz (theta) and 28-64 Hz (gamma) frequency bands...

  19. Innovation and Academic Skills

    DEFF Research Database (Denmark)

    Nielsen, René Nesgaard

    2006-01-01

    Reenen 2001; Acemoglu 2002). In literature based on ‘systems of innovation’ approaches, it has also been argued that science and highly educated workers play increasingly important roles in these systems (Nelson and Rosenberg 1993; Lundvall 2002; Nielsen 1999). Notwithstanding this general trend...... will be written on an assumption of a positive relationship between innovation and use of academic skills subject to a continuing importance of practical know-how and non-formal learning processes. Confronting this assumption with Danish empirics, interesting research questions arise. Danish empirics thus show...... (OECD 2000, 2002, 2005), we may claim that most small firms – fundamentally important in the Danish company structure – are know-how-based without highly educated personnel. This confrontation of literature and Danish empirics leads to research questions such as: • Is skill-bias from innovation and firm...

  20. Music and academic performance.

    Science.gov (United States)

    Arnaud Cabanac; Perlovsky, Leonid; Bonniot-Cabanac, Marie-Claude; Cabanac, Michel

    2013-11-01

    In a previous study we demonstrated that listening to a pleasant music while performing an academic test helped students to overcome stress, to devote more time to more stressful and more complicated task and the grades were higher. Yet, there remained ambiguities as for the causes of the higher test performance of these students: do they perform better because they hear music during their examinations, or would they perform better anyway because they are more gifted/motivated? This motivated the current study as a preliminary step toward that general question: Do students who like/perform music have better grades than the others? Our results confirmed this hypothesis: students studying music have better grades in all subjects. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Academic Education Chain Operation Model

    OpenAIRE

    Ruskov, Petko; Ruskov, Andrey

    2007-01-01

    This paper presents an approach for modelling the educational processes as a value added chain. It is an attempt to use a business approach to interpret and compile existing business and educational processes towards reference models and suggest an Academic Education Chain Operation Model. The model can be used to develop an Academic Chain Operation Reference Model.

  2. Academic underachievement: A neurodevelopmental perspective

    Directory of Open Access Journals (Sweden)

    K. Shapiro Bruce, MD

    2011-03-01

    Full Text Available Academic underachievement is a common presenting symptom and has many different causes. The disorders that describe academic underachievement are based on the child’s function in cognitive, academic, or behavioral domains. The disorders that are associated with academic underachievement are final common pathways that have different etiologies and mechanisms. Multiple disorders are the rule because brain dysfunction in childhood usually affects multiple functions. Consequently, management programs must be individualized, comprehensive and address issues related to the child, school, and family. Treatment plans include parent training, academic accommodations, techniques to maintain self-esteem, and psychopharmacologic approaches. Ongoing monitoring of the management programs is necessary to detect important comorbidities that may emerge, to modify the program to meet the changing academic and social demands that occur as the child ages, and to provide current information. The outcome for children with academic underachievement is most dependent on the underlying disorder. Health providers have multiple roles to play in the prevention, detection, diagnosis and management of children with academic underachievement.

  3. Comics, Copyright and Academic Publishing

    Directory of Open Access Journals (Sweden)

    Ronan Deazley

    2014-05-01

    Full Text Available This article considers the extent to which UK-based academics can rely upon the copyright regime to reproduce extracts and excerpts from published comics and graphic novels without having to ask the copyright owner of those works for permission. In doing so, it invites readers to engage with a broader debate about the nature, demands and process of academic publishing.

  4. Physical Activity and Academic Achievement

    Centers for Disease Control (CDC) Podcasts

    2014-12-09

    This podcast highlights the evidence that supports the link between physical activity and improved academic achievement. It also identifies a few actions to support a comprehensive school physical activity program to improve academic achievement.  Created: 12/9/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 12/9/2014.

  5. Machine Translation for Academic Purposes

    Science.gov (United States)

    Lin, Grace Hui-chin; Chien, Paul Shih Chieh

    2009-01-01

    Due to the globalization trend and knowledge boost in the second millennium, multi-lingual translation has become a noteworthy issue. For the purposes of learning knowledge in academic fields, Machine Translation (MT) should be noticed not only academically but also practically. MT should be informed to the translating learners because it is a…

  6. Diet Quality and Academic Performance

    Science.gov (United States)

    Florence, Michelle D.; Asbridge, Mark; Veugelers, Paul J.

    2008-01-01

    Background: Although the effects of nutrition on health and school performance are often cited, few research studies have examined the effect of diet quality on the academic performance of children. This study examines the association between overall diet quality and academic performance. Methods: In 2003, 5200 grade 5 students in Nova Scotia,…

  7. Defining and Measuring Academic Success

    Science.gov (United States)

    York, Travis T.; Gibson, Charles; Rankin, Susan

    2015-01-01

    Despite, and perhaps because of its amorphous nature, the term "academic success" is one of the most widely used constructs in educational research and assessment within higher education. This paper conducts an analytic literature review to examine the use and operationalization of the term in multiple academic fields. Dominant…

  8. Constructivism, Dewey, and Academic Advising

    Science.gov (United States)

    Xyst, Kurt

    2016-01-01

    Many published scholars argue for constructivism as a basis for academic advising theory. However, few have discussed the commensurate ontological assumptions of constructivist thinking. Potential problems with the metaphysical view of the student in contemporary academic advising may be attributable to constructivism. John Dewey's critique of…

  9. Enrollment Management in Academic Units

    Science.gov (United States)

    DeBiaso, Nick

    2012-01-01

    This study provides an understanding of how administrative leaders make decisions regarding enrollment management within academic units at a major research university in the southwestern United States. Key enrollment management functions of recruiting, admissions, marketing, orientation, financial aid/scholarships, academic advising, student…

  10. Academic Mothers: Exploring Disciplinary Perspectives

    Science.gov (United States)

    Wolf-Wendel, Lisa; Ward, Kelly

    2015-01-01

    In this article we explore the role of academic discipline on the careers of tenure-line faculty women with children. Longitudinal, qualitative findings show that disciplinary contexts and ideal worker norms shape what it means to be an academic and a mother. Even after achieving tenure, ideal worker norms affect these roles; professional…

  11. Integrated Factors Correlating Undergraduate Academic ...

    African Journals Online (AJOL)

    Results revealed that integrated factors had positive impact on students' academic performance. The following integrated factors were found to have contributed relatively to the academic achievement of students in an order of magnitudes; teachers, societal, economic, government, parental, peer group, and individual ...

  12. 'Military Thinkers and Academic Thinkers'

    DEFF Research Database (Denmark)

    Haugegaard, Rikke

    Culture analysis seems to create friction when we try to introduce academic concepts relating to culture to military planners. This friction might be related to the fact that officers and academics do their thinking in different 'spaces'. This paper argues the interface or overlapping space between...

  13. Academic Dishonesty in Medical Schools

    African Journals Online (AJOL)

    Being aware of academic dishonesty in the Medical School made it. 86.3% likely that a student would participate. Having ... Key words: Academic Dishonesty, Medical Training,. Medical Students. Ann Afr Surg. 2017;14(1): 19-21. .... on Plagiarism and Cheating, in Perspectives on Plagiarism and Intellectual Property in the.

  14. Academic Language in Physical Education

    Science.gov (United States)

    Constantinou, Phoebe

    2015-01-01

    This article focuses on defining academic language in physical education and provides a step-by-step approach designed to help preservice and inservice teachers understand and incorporated academic language into their lesson planning. It provides examples of discipline-specific vocabulary, language functions, syntax, and discourse, aiming to…

  15. The Erosion of Academic Freedom

    Science.gov (United States)

    Ledoux, Michael W.; Marshall, Thomas; McHenry, Nadine

    2010-01-01

    This article originated from a single question: do the restrictions that various accrediting agencies place on teacher educators limit, or entirely eliminate, academic freedom? Considering that question makes it apparent the problem is much broader than academic freedom. The issue has two foci: personal identity and the impact of market…

  16. Gendered Games in Academic Leadership

    Science.gov (United States)

    Acker, Sandra

    2010-01-01

    This article looks at women's efforts to construct an academic leadership career. It is not a study of women's leadership in general but one that takes place in what Bourdieu calls the academic field. Drawing from an in-depth interview study of 31 women from faculties of education who occupy managerial positions in universities in Canada,…

  17. Undergraduate students' perceived academic environmental ...

    African Journals Online (AJOL)

    The study revealed that four dimensions of the academic environment as perceived by students, seemed to be potent factors influencing students' attitude to academic work. These perceived factors were: commitment of lecturers to teaching and commitment expected of students; personal attention given to students; ...

  18. Academic Writing: Theory and Practice

    Science.gov (United States)

    Street, Brian V.

    2015-01-01

    In this paper I attempt to locate the study of academic writing in the broader field of Literacies as Social Practice. I begin with a brief summary of recent theories of Literacies as Social Practice and then recount some of the ethnographic methods for studying these. I then discuss the application of these concepts to academic writing in Higher…

  19. Ten Rules of Academic Writing

    NARCIS (Netherlands)

    Donovan, S.K.

    2011-01-01

    Creative writers are well served with 'how to' guides, but just how much do they help? And how might they be relevant to academic authors? A recent survey of writing tips by twenty-eight creative authors has been condensed to the ten most relevant to the academic, supported by some comments on

  20. Healthy Eating and Academic Achievement

    Centers for Disease Control (CDC) Podcasts

    2014-12-09

    This podcast highlights the evidence that supports the link between healthy eating and improved academic achievement. It also identifies a few actions to support a healthy school nutrition environment to improve academic achievement.  Created: 12/9/2014 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 12/9/2014.

  1. Entrepreneurship Education and Academic Performance

    Science.gov (United States)

    Johansen, Vegard

    2014-01-01

    The significant increase of entrepreneurship education (EE) is a trend in Europe. Entrepreneurship education is supposed to promote general and specific entrepreneurial abilities and improve academic performance. This paper evaluates whether EE influences academic performance, measured by Grade Point Average. The main indicator used for EE is the…

  2. Financing Academic Departments of Psychiatry

    Science.gov (United States)

    Liptzin, Benjamin; Meyer, Roger E.

    2011-01-01

    Objective: The authors describe the many financial challenges facing academic departments of psychiatry and the resulting opportunities that may arise. Method: The authors review the history of financial challenges, the current economic situation, and what may lie ahead for academic departments of psychiatry. Results: The current environment has…

  3. Learning increases human electroencephalographic coherence during subsequent slow sleep oscillations

    OpenAIRE

    Mölle, Matthias; Marshall, Lisa; Gais, Steffen; Born, Jan

    2004-01-01

    Learning is assumed to induce specific changes in neuronal activity during sleep that serve the consolidation of newly acquired memories. To specify such changes, we measured electroencephalographic (EEG) coherence during performance on a declarative learning task (word pair associations) and subsequent sleep. Compared with a nonlearning control condition, learning performance was accompanied with a strong increase in coherence in several EEG frequency bands. During subsequent non-rapid eye m...

  4. Cesarean Delivery and Risk for Subsequent Ectopic Pregnancy.

    Science.gov (United States)

    Bowman, Zachary S; Smith, Ken R; Silver, Robert M

    2015-07-01

    This study aims to examine the risk for subsequent ectopic pregnancy in women with prior cesarean delivery. Women with a history of at least one cesarean delivery in the state of Utah during 1996 to 2011 were identified and compared with women with vaginal delivery only. The primary outcome was subsequent ectopic pregnancy. Data were analyzed by multivariate logistic regression and stratified by first, second, or third live births. Model covariates included maternal age, ethnicity, marital status, education level, gravidity, and prior ectopic pregnancy. Overall, 260,249 women with at least one live birth were identified. After exclusions, 255,082, 154,930, and 70,228 women had at least one, two, and three prior live births that lead to 531, 199, and 62 subsequent ectopic pregnancies, respectively. Women who had one prior cesarean delivery were not at increased risk for subsequent ectopic pregnancy in relation to women with no prior cesarean delivery. However, women with two of two, two of three, or three of three prior cesareans had increased risk for subsequent ectopic pregnancy with odds ratios (95% confidence interval) of 1.54 (1.06-2.22), 3.50 (1.49-8.24), and 1.99 (1.00-3.98), respectively. History of two or three cesarean deliveries is associated with increased risk for subsequent ectopic pregnancy. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  5. Processing fluency hinders subsequent recollection: An electrophysiological study

    Directory of Open Access Journals (Sweden)

    Bingbing eLi

    2015-06-01

    Full Text Available Although many behavioural studies have investigated the effect of processing fluency on subsequent recognition memory, little research has examined the neural mechanism of this phenomenon. The present study aimed to explore the electrophysiological correlates of the effects of processing fluency on subsequent recognition memory by using an event-related potential (ERP approach. The masked repetition priming paradigm was used to manipulate processing fluency in the study phase, and the R/K paradigm was utilised to investigate which recognition memory process (familiarity or recollection was affected by processing fluency in the test phase. Converging behavioural and ERP results indicated that increased processing fluency impaired subsequent recollection. Results from the analysis of ERP priming effects in the study phase indicated that increased perceptual processing fluency of object features, reflected by the N/P 190 priming effect, can hinder encoding activities, reflected by the LPC priming effect, which leads to worse subsequent recollection based recognition memory. These results support the idea that processing fluency can influence subsequent recognition memory and provide a potential neural mechanism underlying this effect. However, further studies are needed to examine whether processing fluency can affect subsequent familiarity.

  6. Processing fluency hinders subsequent recollection: an electrophysiological study.

    Science.gov (United States)

    Li, Bingbing; Gao, Chuanji; Wang, Wei; Guo, Chunyan

    2015-01-01

    Although many behavioral studies have investigated the effect of processing fluency on subsequent recognition memory, little research has examined the neural mechanism of this phenomenon. The present study aimed to explore the electrophysiological correlates of the effects of processing fluency on subsequent recognition memory by using an event-related potential (ERP) approach. The masked repetition priming paradigm was used to manipulate processing fluency in the study phase, and the R/K paradigm was utilized to investigate which recognition memory process (familiarity or recollection) was affected by processing fluency in the test phase. Converging behavioral and ERP results indicated that increased processing fluency impaired subsequent recollection. Results from the analysis of ERP priming effects in the study phase indicated that increased perceptual processing fluency of object features, reflected by the N/P 190 priming effect, can hinder encoding activities, reflected by the LPC priming effect, which leads to worse subsequent recollection based recognition memory. These results support the idea that processing fluency can influence subsequent recognition memory and provide a potential neural mechanism underlying this effect. However, further studies are needed to examine whether processing fluency can affect subsequent familiarity.

  7. Academic entitlement in pharmacy education.

    Science.gov (United States)

    Cain, Jeff; Romanelli, Frank; Smith, Kelly M

    2012-12-12

    The constructs of academic entitlement and student consumerism refer to students' attitudes toward education as a commodity and the underlying belief that as consumers, they should be catered to and given the opportunity to participate in the education process according to their preferences. Most discussions regarding these attitudes are anecdotal, but the pervasiveness of these accounts and the troubling effects that ensue warrant attention. Grade inflation, student incivility, altered classroom practices, and decreased faculty morale are all potential aftereffects of teaching students who hold academic entitlement beliefs. Numerous factors are posited as attributing to academic entitlement including personal issues, societal pressures, and broad academic practices. This paper discusses these factors and offers faculty members and administrators recommendations regarding practices that may curb or alleviate issues associated with academically entitled students.

  8. Academic sensemaking and behavioural responses

    DEFF Research Database (Denmark)

    Degn, Lise

    2018-01-01

    Reforms and changing ideas about what higher education institutions are and should be have put pressure on academic identity. The present paper explores the way academics in Danish universities make sense of their changing circumstances, and how this affects their perceptions of their organization......, their leaders and of themselves. The study highlights how the formal organizations’ translations of external impulses and ideas constitute a more severe threat on the perceived identity of the academic staff than the impulses and ideas themselves. The findings indicate that with the tighter couplings of top......-level management and the political system, the coupling and identification between academic staff and the formal organization may become weaker. Also, the behavioural responses perceived threats are studied, by examining the ‘us’/‘them’ categorizations of the academics, providing a burgeoning conceptual framework...

  9. Academic etiquette for the nephrologist.

    Science.gov (United States)

    Watnick, Suzanne

    2008-11-01

    Academic etiquette is an underexplored and underemphasized topic. Yet, a collegial atmosphere is essential to accomplish the missions of an academic medical center. Appropriate social, personal, and cultural behaviors are not only desirable, but they are also necessary to practice and emulate. As faculty in an academic center, one may want to share these thoughts with peers, students, and other healthcare providers. As a trainee, one may want dedicated lectures on this topic and to observe the behaviors modeled by mentors. This article attempts to outline principles of appropriate etiquette in the academic workplace. These include issues of loyalty, collegiality, and collaboration in daily activities from research to clinical care. Approaching personal interactions with grace and integrity can be an essential tool in the pursuit of academic excellence and success.

  10. The Intertwined Nature of Adolescents' Social and Academic Lives: Social and Academic Goal Orientations

    Science.gov (United States)

    Ben-Eliyahu, Adar; Linnenbrink-Garcia, Lisa; Putallaz, Martha

    2017-01-01

    The relations of academic and social goal orientations to academic and social behaviors and self-concept were investigated among academically talented adolescents (N = 1,218) attending a mastery-oriented academic residential summer program. Results supported context effects in that academic mastery goal orientations predicted academic (in-class…

  11. University Students' Satisfaction with their Academic Studies: Personality and Motivation Matter.

    Science.gov (United States)

    Wach, F-Sophie; Karbach, Julia; Ruffing, Stephanie; Brünken, Roland; Spinath, Frank M

    2016-01-01

    Although there is consensus about the importance of students' satisfaction with their academic studies as one facet of academic success, little is known about the determinants of this significant outcome variable. Past research rarely investigated the predictive power of multiple predictors simultaneously. Hence, we examined how demographic variables, personality, cognitive and achievement-related variables (intelligence, academic achievement), as well as various motivational constructs were associated with three different dimensions of satisfaction (satisfaction with study content, satisfaction with the conditions of the academic program, satisfaction with the ability to cope with academic stress) assessed approximately 2 years apart. Analyzing data of a sample of university students (N = 620; M age = 20.77; SD age = 3.22) using structural equation modeling, our results underline the significance of personality and motivational variables: Neuroticism predicted satisfaction with academic studies, but its relevance varied between outcome dimensions. Regarding the predictive validity of motivational variables, the initial motivation for enrolling in a particular major was correlated with two dimensions of subsequent satisfaction with academic studies. In contrast, the predictive value of cognitive and achievement-related variables was relatively low, with academic achievement only related to satisfaction with the conditions of the academic program after controlling for the prior satisfaction level.

  12. University students’ satisfaction with their academic studies: personality and motivation matter

    Directory of Open Access Journals (Sweden)

    F.-Sophie eWach

    2016-02-01

    Full Text Available Although there is consensus about the importance of students’ satisfaction with their academic studies as one facet of academic success, little is known about the determinants of this significant outcome variable. Past research rarely investigated the predictive power of multiple predictors simultaneously. Hence, we examined how demographic variables, personality, cognitive and achievement-related variables (intelligence, academic achievement, as well as various motivational constructs were associated with three different dimensions of satisfaction (satisfaction with study content, satisfaction with the conditions of the academic program, satisfaction with the ability to cope with academic stress assessed approximately two years apart. Analyzing data of a sample of university students (N = 620; Mage = 20.77; SDage = 3.22 using structural equation modeling, our results underline the significance of personality and motivational variables: Neuroticism predicted satisfaction with academic studies, but its relevance varied between outcome dimensions. Regarding the predictive validity of motivational variables, the initial motivation for enrolling in a particular major was correlated with two dimensions of subsequent satisfaction with academic studies. In contrast, the predictive value of cognitive and achievement-related variables was relatively low, with academic achievement only related to satisfaction with the conditions of the academic program after controlling for the prior satisfaction level.

  13. Measuring Academic Motivation of Matriculating College Freshmen.

    Science.gov (United States)

    Baker, Robert W.; Siryk, Bohdan

    1984-01-01

    Administered the Academic Motivation Scale to three successive classes of college freshmen (N=944). Results indicated the Academic Motivation Scale's reliability was more than adequate for research use and significantly related to validity criteria reflecting motivation for academic work. (JAC)

  14. ACADEMIC MOTIVATION FOR BUSINESS INFORMATION SYSTEMS STUDENTS

    National Research Council Canada - National Science Library

    Catalin Maican; Radu Lixandroiu

    2015-01-01

    Academic Motivation Scale (AMS) was applied to Business Information Systems students for finding out their reasons and motives for enrolling this academic field, for undergraduate and postgraduate academic cycles...

  15. Mental health predicts better academic outcomes: a longitudinal study of elementary school students in Chile.

    Science.gov (United States)

    Murphy, J Michael; Guzmán, Javier; McCarthy, Alyssa E; Squicciarini, Ana María; George, Myriam; Canenguez, Katia M; Dunn, Erin C; Baer, Lee; Simonsohn, Ariela; Smoller, Jordan W; Jellinek, Michael S

    2015-04-01

    The world's largest school-based mental health program, Habilidades para la Vida [Skills for Life (SFL)], has been operating on a national scale in Chile for 15 years. SFL's activities include using standardized measures to screen elementary school students and providing preventive workshops to students at risk for mental health problems. This paper used SFL's data on 37,397 students who were in first grade in 2009 and third grade in 2011 to ascertain whether first grade mental health predicted subsequent academic achievement and whether remission of mental health problems predicted improved academic outcomes. Results showed that mental health was a significant predictor of future academic performance and that, overall, students whose mental health improved between first and third grade made better academic progress than students whose mental health did not improve or worsened. Our findings suggest that school-based mental health programs like SFL may help improve students' academic outcomes.

  16. Mental health predicts better academic outcomes: A longitudinal study of elementary school students in Chile

    Science.gov (United States)

    Murphy, J. Michael; Guzmán, Javier; McCarthy, Alyssa; Squicciarini, Ana María; George, Myriam; Canenguez, Katia; Dunn, Erin C.; Baer, Lee; Simonsohn, Ariela; Smoller, Jordan W.; Jellinek, Michael

    2015-01-01

    The world’s largest school-based mental health program, Habilidades para la Vida [Skills for Life, SFL], has been operating at a national scale in Chile for fifteen years. SFL’s activities include using standardized measures to screen elementary school students and providing preventive workshops to students at risk for mental health problems. This paper used SFL’s data on 37,397 students who were in first grade in 2009 and third grade in 2011 to ascertain whether first grade mental health predicted subsequent academic achievement and whether remission of mental health problems predicted improved academic outcomes. Results showed that mental health was a significant predictor of future academic performance and that, overall, students whose mental health improved between first and third grade made better academic progress than students whose mental health did not improve or worsened. Our findings suggest that school-based mental health programs like SFL may help improve students’ academic outcomes. PMID:24771270

  17. ACADEMIC ACHIEVEMENT OF HIGH SCHOOL STUDENTS IN RELATION TO THEIR EMOTIONAL STABILITY

    Directory of Open Access Journals (Sweden)

    Sima Kalita

    2016-10-01

    Full Text Available In the present study an attempt was made to know the relationship between personality factor emotional stability and academic achievement of the high school students of South Kamrup district of Assam, India. Students were randomly selected from different high schools of the selected area. A sample of 400(both boys and girls students was selected and Cattell’s Jr. High School Personality Questionnaire (HSPQ was administered to them and record of academic achievement was collected from the school record. Subsequently the data were subjected to statistical analysis with the help of percentage analysis and x2. Results indicated a significant relationship between emotional stability and academic achievement of high school students of South kamrup district, Assam, India. The study also depicted that high level of emotional stability leads to high academic achievement and low emotional stability leads to low level of academic achievement.

  18. Changing Academic Identities in Changing Academic Workplaces: Learning from Academics' Everyday Professional Writing Practices

    Science.gov (United States)

    Lea, Mary R.; Stierer, Barry

    2011-01-01

    In this article we examine issues of academic identity through the lens of academics' everyday workplace writing, offering a complementary perspective to those already evident in the higher education research literature. Motivated by an interest in the relationship between routine writing and aspects of professional practice, we draw on data from…

  19. Academic Performance in Adolescence after Inguinal Hernia Repair in Infancy: A Nationwide Cohort Study

    DEFF Research Database (Denmark)

    Hansen, Tom G; Pedersen, Jacob K; Henneberg, Steen Winther

    2011-01-01

    for inguinal hernia repair in infancy and subsequent academic performance. METHODS:: Using Danish birth cohorts from 1986-1990, we compared the academic performance of all children who had undergone inguinal hernia repair in infancy to a randomly selected, age-matched 5% population sample. Primary analysis...... found no evidence that a single, relatively brief anesthetic exposure in connection with hernia repair in infancy reduced academic performance at age 15 or 16 yr after adjusting for known confounding factors. However, the higher test score nonattainment rate among the hernia group could suggest...

  20. Caesarean section and subsequent fertility in sub-Saharan Africa.

    Science.gov (United States)

    Collin, S M; Marshall, T; Filippi, V

    2006-03-01

    To determine the impact of caesarean section on fertility among women in sub-Saharan Africa. Analysis of standardised cross-sectional surveys (Demographic and Health Surveys). Twenty-two countries in sub-Saharan Africa, 1993-2003. A total of 35 398 women of childbearing age (15-49 years). Time to subsequent pregnancy was compared by mode of delivery using Cox proportional hazards regression models. Natural fertility rates subsequent to delivery by caesarean section compared with natural fertility rates subsequent to vaginal delivery. The natural fertility rate subsequent to delivery by caesarean section was 17% lower than the natural fertility rate subsequent to vaginal delivery (hazard ratio = 0.83, 95% CI 0.73-0.96, P Caesarean section was also associated with prior fertility and desire for further children: among multiparous women, an interval > or =3 versus caesarean section at the index birth (OR = 1.4, 95% CI 1.1-1.7, P= 0.005); among all women, the odds of desiring further children were lower among women who had previously delivered by caesarean section (OR = 0.67, 95% CI 0.54-0.84, P Caesarean section did not appear to increase the risk of a subsequent pregnancy ending in miscarriage, abortion or stillbirth. Among women in sub-Saharan Africa, caesarean section is associated with lower subsequent natural fertility. Although this reflects findings from developed countries, the roles of pathological and psychological factors may be quite different because a much higher proportion of caesarean sections in sub-Saharan Africa are emergency procedures for maternal indication.

  1. A Test of the Reciprocal-Effects Model of Academic Achievement and Academic Self-Concept in Regular Classes and Special Classes for the Gifted

    Science.gov (United States)

    Preckel, Franzis; Schmidt, Isabelle; Stumpf, Eva; Motschenbacher, Monika; Vogl, Katharina; Schneider, Wolfgang

    2017-01-01

    According to the reciprocal-effects model (REM), prior academic self-concept (ASC) has a positive effect on subsequent achievement beyond what can be explained in terms of prior achievement and vice versa. The present study investigated the REM for students studying in special classes for the gifted compared to students studying in regular…

  2. Subsequent pregnancy outcomes after obstetric anal sphincter injuries (OASIS).

    Science.gov (United States)

    Basham, Elizabeth; Stock, Laura; Lewicky-Gaupp, Christina; Mitchell, Christopher; Gossett, Dana R

    2013-01-01

    To describe obstetric outcomes in women with a prior obstetric anal sphincter injury (OASIS) and to identify risk factors for recurrence. A retrospective chart review of women who sustained an OASIS between November 2005 and March 2010 at a tertiary care hospital was performed to identify risk factors for recurrence. One thousand six hundred twenty-nine patients had an OASIS. Of these, 758 patients (90%) subsequently delivered during the aforementioned timeframe; 685 patients had a subsequent vaginal delivery. Of the women, 3.2% had a recurrent OASIS. Recurrence was associated with larger birth weight (27% ≥4000 g vs 11.6% <4000 g; P = 0.04) and delivery mode (25.0%, 12.5%, and 2.7% for forceps-assisted, vacuum-assisted, and spontaneous deliveries, respectively (P = 0.0001)), whereas a history of fourth-degree laceration, prior wound complication, or episiotomy at subsequent delivery were not (P = 0.5, P = 0.5, and P = 0.4, respectively). Recurrent OASIS occurred in a small percentage of women (3.2%) who subsequently delivered vaginally. Recurrent OASIS was associated with operative vaginal delivery and birth weight 4000 g or greater. Neither episiotomy at first delivery nor at subsequent delivery conferred an increased recurrence risk.

  3. Cortisol awakening response and subsequent depression: prospective longitudinal study.

    Science.gov (United States)

    Carnegie, Rebecca; Araya, Ricardo; Ben-Shlomo, Yoav; Glover, Vivette; O'Connor, Thomas G; O'Donnell, Kieran J; Pearson, Rebecca; Lewis, Glyn

    2014-02-01

    Some studies have found an association between elevated cortisol and subsequent depression, but findings are inconsistent. The cortisol awakening response may be a more stable measure of hypothalamic-pituitary-adrenal function and potentially of stress reactivity. To investigate whether salivary cortisol, particularly the cortisol awakening response, is associated with subsequent depression in a large population cohort. Young people (aged 15 years, n = 841) from the Avon Longitudinal Study of Parents and Children (ALSPAC) collected salivary cortisol at four time points for 3 school days. Logistic regression was used to calculate odds ratios for developing depression meeting ICD-10 criteria at 18 years. We found no evidence for an association between salivary cortisol and subsequent depression. Odds ratios for the cortisol awakening response were 1.24 per standard deviation (95% CI 0.93-1.66, P = 0.14) before and 1.12 (95% CI 0.73-1.72, P = 0.61) after adjustment for confounding factors. There was no evidence that the other cortisol measures, including cortisol at each time point, diurnal drop and area under the curve, were associated with subsequent depression. Our findings do not support the hypothesis that elevated salivary cortisol increases the short-term risk of subsequent depressive illness. The results suggest that if an association does exist, it is small and unlikely to be of clinical significance.

  4. Failure of fertility therapy and subsequent adverse cardiovascular events

    Science.gov (United States)

    Udell, Jacob A.; Lu, Hong; Redelmeier, Donald A.

    2017-01-01

    BACKGROUND: Infertility may indicate an underlying predisposition toward premature cardiovascular disease, yet little is known about potential long-term cardiovascular events following fertility therapy. We investigated whether failure of fertility therapy is associated with subsequent adverse cardiovascular events. METHODS: We performed a population-based cohort analysis of women who received gonadotropin-based fertility therapy between Apr. 1, 1993, and Mar. 31, 2011, distinguishing those who subsequently gave birth and those who did not. Using multivariable Poisson regression models, we estimated the relative rate ratio of adverse cardiovascular events associated with fertility therapy failure, accounting for age, year, baseline risk factors, health care history and number of fertility cycles. The primary outcome was subsequent treatment for nonfatal coronary ischemia, stroke, transient ischemic attack, heart failure or thromboembolism. RESULTS: Of 28 442 women who received fertility therapy, 9349 (32.9%) subsequently gave birth and 19 093 (67.1%) did not. The median number of fertility treatments was 3 (interquartile range 1–5). We identified 2686 cardiovascular events over a median 8.4 years of follow-up. The annual rate of cardiovascular events was 19% higher among women who did not give birth after fertility therapy than among those who did (1.08 v. 0.91 per 100 patient-years, p treatment cycles. INTERPRETATION: Fertility therapy failure was associated with an increased risk of long-term adverse cardiovascular events. These women merit surveillance for subsequent cardiovascular events. PMID:28385819

  5. Subsequent pregnancies in women with previous gestational syphilis.

    Science.gov (United States)

    Hebmuller, Marjorie Garlow; Fiori, Humberto Holmer; Lago, Eleonor Gastal

    2015-09-01

    This study included data on syphilis-positive pregnant women seen for delivery or miscarriage, between 1997 and 2004, in Sao Lucas Hospital, Porto Alegre, RS. Their subsequent obstetric outcomes were studied, until December 2011, to see if the disease recurred. From 450 pregnant women with positive syphilis serology, seen from 1997 to 2004, 166 had at least one more obstetric attendance until December 2011, with 266 new obstetric outcomes. Congenital syphilis (CS) was demonstrated in 81.9% of the initial pregnancies and in 68.4% of the subsequent ones. The main causes of CS in subsequent pregnancies were a negative VDRL that turned positive at delivery, and undocumented treatment. VDRL titers were higher than 1:4 in 50.4% of the initial and 13.3% of the subsequent pregnancies (p syphilis in a preceding pregnancy. No or inadequate prenatal care was the main risk factor for CS, both in initial and in subsequent pregnancies. These data suggest that non-infected neonates could have been defined as CS cases because of insufficient information about the mother's history.

  6. Academic journalese for the Internet

    DEFF Research Database (Denmark)

    Yli-Jokipii, Hilkka; Jørgensen, Poul Erik Flyvholm

    2004-01-01

    The purpose of the present study is to investigate, within the textual framework of academic journalese, what happens to Danish and Finnish writers' English texts when edited by native English-speaking editors for publication on the World Wide Web. We use the term academic journalese to describe...... texts written by researchers or professionals with a background in research that are easily available to large audiences outside the academic world. By using rhetorical, text linguistic, and editorial concepts in the analysis, we have traced and identified the types of changes to which a number of texts...

  7. Active Versus Passive Academic Networking

    DEFF Research Database (Denmark)

    Goel, Rajeev K.; Grimpe, Christoph

    2013-01-01

    This paper examines determinants of networking by academics. Using information from a unique large survey of German researchers, the key contribution focuses on the active versus passive networking distinction. Is active networking by researchers a substitute or a complement to passive networking...... that some types of passive academic networking are complementary to active networking, while others are substitute. Further, we find differences in factors promoting participation in European conferences versus conferences in rest of the world. Finally, publishing bottlenecks as a group generally do...... not appear to be a hindrance to active networking. Implications for academic policy are discussed...

  8. Academic procrastination: An exploratory study

    Directory of Open Access Journals (Sweden)

    Rita Karina Nobre Sampaio

    2011-10-01

    Full Text Available Academic procrastination has been understood as a dynamic phenomenon, which involves personal, behavioral and environmental issues and is characterized by the postponement of non-strategic actions. This behavior may affect the academic performance of the students. The present study aimed to describe the procrastination among university students, and identify activities that are more or less delayed and feelings reported to be procrastinating.The results indicate the frequency of procrastination among university students, as well as a list of academic tasks and unpleasant feelings postponed to procrastinate.

  9. The survey of academic libraries

    CERN Document Server

    2014-01-01

    The Survey of Academic Libraries, 2014-15 Edition looks closely at key benchmarks for academic libraries in areas such as spending for books and e-books, deployment and pay rates for student workers, use of tablet computers, cloud computing and other new technologies, database licensing practices, and much more. The study includes detailed data on overall budgets, capital budgets, salaries and materials spending, and much more of interest to academic librarians and their suppliers. Data in this 200+ page report is broken out by size and type of library for easy benchmarking.

  10. Learning Commons in Academic Libraries

    Directory of Open Access Journals (Sweden)

    Larisa González Martínez

    2015-01-01

    Full Text Available Like all human creations, institutions transform and evolve over time. Libraries also have changed to respond the needs of its users. Academic libraries physical spaces are one of the turned aspects, an example are the Learning Commons (spaces for collaborative work in academic libraries. The main purpose of this paper is to expose the characteristics of the Learning Commons model with a brief account of the history of planning and construction of academic libraries. This paper also aims to present the manner in which a Learning Commons has been implemented at the library of Instituto Tecnológico y de Estudios Superiores de Monterrey (ITESM, Campus Monterrey in Mexico.

  11. New threats to academic freedom.

    Science.gov (United States)

    Minerva, Francesca

    2014-05-01

    Using a specific case as an example, the article argues that the Internet allows dissemination of academic ideas to the general public in ways that can sometimes pose a threat to academic freedom. Since academic freedom is a fundamental element of academia and since it benefits society at large, it is important to safeguard it. Among measures that can be taken in order to achieve this goal, the publication of anonymous research seems to be a good option. © 2013 John Wiley & Sons Ltd.

  12. ACADEMIC TRAINING LECTURE

    CERN Multimedia

    Academic Training; Tel. 73127

    2001-01-01

    ACADEMIC TRAINING LECTURE 1, 2, 3, 4 and 5 October LECTURES FOR POSTGRADUATE STUDENTS From 10:00 hrs - Main Auditorium bldg. 500 1 Introduction to particle accelerators E.J.N. Wilson / CERN-AC , Head of the CERN Accelerator School This new series of lectures is intended for anyone with a technical or scientific background who would like to become familiar with the principles of accelerator design. It is a complement to last year's course and includes new lectures on present day accelerators, and their applications as well as colliders and neutrino factories. Beam dynamics, which was treated at length in last year's course, has been compressed into one lecture, intended as revision for those who followed earlier courses and an introduction for newcomers to the field. The course should not be missed by those who will attend the CAS Intermediate Accelerator School in Seville. 1-10 10:00 Present-day Accelerators 11:00 - Beam Dynamics 2-10 10:00 Accelerating Cavities 11:00 - Non-linear Dynamics 3-10 10:00 E...

  13. Academic geriatrics in Singapore.

    Science.gov (United States)

    Wong, Chek Hooi; Landefeld, C Seth

    2011-11-01

    Singapore is one of the fastest-aging countries in the world. The proportion of adults aged 65 and older is projected to increase from 8.7% to 20% over the next 20 years. The country has developed various strategies to meet the needs of this increase in older adults. There is an acute shortage of geriatricians and a need to train more healthcare workers to care for older adults. Geriatric medicine is a relatively new specialty, and a small number of geriatricians have been tasked with providing an increasing load of clinical service, education, and research. Hence, there is a need to develop a cohesive structure of support for faculty development and retention, advanced specialty trainee recruitment, leadership in medical education, research, and clinical service to care for the rapidly aging population. In addition, geriatric medicine is primarily a hospital-based specialty in Singapore. There is still opportunity to collaborate and improve the academic and practice integration of geriatric medicine into primary care and intermediate and long-term care where it is most needed. © 2011, Copyright the Authors Journal compilation © 2011, The American Geriatrics Society.

  14. The academic library network

    Directory of Open Access Journals (Sweden)

    Jacek Wojciechowski

    2012-01-01

    Full Text Available The efficiency of libraries, academic libraries in particular, necessitates organizational changes facilitating or even imposing co-operation. Any structure of any university has to have an integrated network of libraries, with an appropriate division of work, and one that is consolidated as much as it is possible into medium-size or large libraries. Within thus created network, a chance arises to centralize the main library processes based on appropriate procedures in the main library, highly specialized, more effective and therefore cheaper in operation, including a co-ordination of all more important endeavours and tasks. Hierarchically subordinated libraries can be thus more focused on performing their routine service, more and more frequently providing for the whole of the university, and being able to adjust to changeable requirements and demands of patrons and of new tasks resulting from the new model of the university operation. Another necessary change seems to be a universal implementation of an ov rall programme framework that would include all services in the university’s library networks.

  15. Faster Algorithms for Computing Longest Common Increasing Subsequences

    DEFF Research Database (Denmark)

    Kutz, Martin; Brodal, Gerth Stølting; Kaligosi, Kanela

    2011-01-01

    of the alphabet, and Sort is the time to sort each input sequence. For k⩾3 length-n sequences we present an algorithm which improves the previous best bound by more than a factor k for many inputs. In both cases, our algorithms are conceptually quite simple but rely on existing sophisticated data structures......We present algorithms for finding a longest common increasing subsequence of two or more input sequences. For two sequences of lengths n and m, where m⩾n, we present an algorithm with an output-dependent expected running time of and O(m) space, where ℓ is the length of an LCIS, σ is the size....... Finally, we introduce the problem of longest common weakly-increasing (or non-decreasing) subsequences (LCWIS), for which we present an -time algorithm for the 3-letter alphabet case. For the extensively studied longest common subsequence problem, comparable speedups have not been achieved for small...

  16. Effect of uniaxiai ratcheting on subsequent creep deformation

    Science.gov (United States)

    Sasaki, Katsuhiko; Ishikawa, Hiromasa

    1998-05-01

    Experimental observation and numerical simulation are conducted to clarify the effect of viscosity on deformation of materials. First, creep tests after the primary uniaxial ratcheting are carded out using Type 304 stainless steel. Specimens are subjected to cyclic tension-unloading with step and triangular waves during 20000 seconds as the primary ratcheting. After the ratcheting the subsequent creep test at the maximum stress is conducted during 20000 seconds. The experimental results show that the values of the subsequent creep strain after the ratcheting depend on the wave type and the time period of the ratcheting. The shorter time period of the ratcheting leads to the larger subsequent creep strain. Numerical simulations are also carried out using the constitutive model based on dislocation density [Estrin et al.]. As a result, the equivalent value of the ratcheting strain to creep strain is found out from the simulations and experiments.

  17. Computer Anxiety, Academic Stress, and Academic Procrastination on College Students

    OpenAIRE

    Rahardjo, Wahyu; Juneman, Juneman; Setiani, Yeni

    2013-01-01

    Academic procrastination is fairly and commonly found among college students. The lack of understanding in making the best use of computer technology may lead to anxiety in terms of operating computer hence cause postponement in completing course assignments related to computer operation. On the other hand, failure in achieving certain academic targets as expected by parents and/or the students themselves also makes students less focused and leads to tendency of postponing many completions of...

  18. Performance samples on academic tasks: improving prediction of academic performance

    OpenAIRE

    Tanilon, Jenny

    2011-01-01

    This thesis is about the development and validation of a performance-based test, labeled as Performance Samples on academic tasks in Education and Child Studies (PSEd). PSEd is designed to identify students who are most able to perform the academic tasks involved in an Education and Child Studies bridging program. Many Dutch universities set up bridging programs that aim to prepare students with non-university degrees in the Netherlands for Master’s programs at the university level. Some univ...

  19. A Novel Image Encryption Algorithm Based on DNA Subsequence Operation

    Directory of Open Access Journals (Sweden)

    Qiang Zhang

    2012-01-01

    Full Text Available We present a novel image encryption algorithm based on DNA subsequence operation. Different from the traditional DNA encryption methods, our algorithm does not use complex biological operation but just uses the idea of DNA subsequence operations (such as elongation operation, truncation operation, deletion operation, etc. combining with the logistic chaotic map to scramble the location and the value of pixel points from the image. The experimental results and security analysis show that the proposed algorithm is easy to be implemented, can get good encryption effect, has a wide secret key's space, strong sensitivity to secret key, and has the abilities of resisting exhaustive attack and statistic attack.

  20. Academic Locus of Control, Tendencies Towards Academic Dishonesty and Test Anxiety Levels as the Predictors of Academic Self-Efficacy

    Science.gov (United States)

    Yesilyurt, Etem

    2014-01-01

    Many studies have focused on finding the level of effect that academic locus of control, tendencies towards academic dishonesty, and test anxiety levels have had on academic self-efficacy, and providing a separate explanation ratio for each. The relationship among the effects of the academic locus of control, tendencies towards academic…

  1. The Role of Academic Self-Efficacy as a Mediator Variable between Perceived Academic Climate and Academic Performance

    Science.gov (United States)

    Abd-Elmotaleb, Moustafa; Saha, Sudhir K.

    2013-01-01

    This study examines the mediating influence of academic self-efficacy on the link between perceived academic climate and academic performance among university students. The participants in the study consist of 272 undergraduate students at the University of Assiut, Assiut, Egypt. A scale to measure perceived academic climate, was developed. To…

  2. ACADEMIC TRAINING LECTURES-QUESTIONNAIRE

    CERN Multimedia

    Françoise Benz

    2004-01-01

    ACADEMIC TRAINING Françoise Benz tel. 73127 academic.training@cern.ch SUGGEST AND WIN! Its time to plan the 2004-2005 lecture series. From today until March 19 you have the chance to give your contribution to planning for next year's Academic Training Lecture Series. At the web site: http://cern.ch/Academic.Training/questionnaire you will find questionnaires proposing topics in high energy physics, applied physics and science and society. Answering the questionnaire will help ensure that the selected topics are as close as possible to your interests. In particular requests and comments from students will be much appreciated. To encourage your contribution, the AT Committee will reward one lucky winner with a small prize, a 50 CHF coupon for a book purchase at the CERN bookshop.

  3. Self-initiated expatriate academics

    DEFF Research Database (Denmark)

    Selmer, Jan; Lauring, Jakob

    2013-01-01

    In this chapter we examine self-initiated expatriate academics. Universities are to an increasing extent looking for talent beyond national boundaries. Accordingly, self-initiated expatriate academics represent a fast growing group of highly educated professionals who gain employment abroad....... Nonetheless, little research has focused on this group. We investigate if personal characteristics such as age, gender, marital status and seniority affect work outcomes such as work adjustment, work performance, work effectiveness, job satisfaction and time to proficiency. This is done by using data which...... were collected from 428 self-initiated expatriate academics from 60 countries employed in 35 universities in five northern European countries. Results confirm that there are differences in terms of work outcomes among the different types of self-initiated expatriate academics, especially regarding...

  4. Personality, academic majors and performance

    DEFF Research Database (Denmark)

    Vedel, Anna; Thomsen, Dorthe Kirkegaard; Larsen, Lars

    2015-01-01

    Personality–performance research typically uses samples of psychology students without questioning their representativeness. The present article reports two studies challenging this practice. Study 1: group differences in the Big Five personality traits were explored between students (N = 1067......) in different academic majors (medicine, psychology, law, economics, political science, science, and arts/humanities), who were tested immediately after university enrolment. Study 2: six and a half years later the students’ academic records were obtained, and predictive validity of the Big Five personality...... traits and their subordinate facets was examined in the various academic majors in relation to Grade Point Average (GPA). Significant group differences in all Big Five personality traits were found between students in different academic majors. Also, variability in predictive validity of the Big Five...

  5. Revising Academic Library Governance Handbooks

    Directory of Open Access Journals (Sweden)

    Jen Stevens

    2015-07-01

    Full Text Available Regardless of our status (tenure track, non-tenure track, staff, and/or union, academic librarians at colleges and universities may use a handbook or similar document as a framework for self-governance. These handbooks typically cover rank descriptions, promotion requirements, and grievance rights, among other topics. Unlike employee handbooks used in the corporate world, these documents may be written and maintained by academic librarians themselves1. In 2010, a group of academic librarians at George Mason University was charged with revising our Librarians’ Handbook. Given the dearth of literature about academic librarians’ handbooks and their revision, we anticipate our library colleagues in similar situations will benefit from our experience and recommendations.

  6. Perfectionism, depression, and academic performance.

    Science.gov (United States)

    Leenaars, Lindsey; Lester, David

    2006-12-01

    In samples of 30 Canadian and 117 American undergraduates, academic performance was more strongly correlated with perfectionism scores (Revised Almost Perfect Scale) (r = .20 and -.17) than with those on self-reported depression (CES-Depression) (r = -.09).

  7. Ruminations on the Academic Afterlife

    National Research Council Canada - National Science Library

    Daniel Dustin; Gene Lamke; James Murphy; Cary McDonald; Brett Wright; Jack Harper

    2015-01-01

      In this paper, the academic afterlife of a purposive sample of 12 recreation, park, and leisure studies educators from a variety of universities throughout the United States and Canada is discussed...

  8. Collection Development in Academic Libraries.

    Science.gov (United States)

    Frankie, Suzanne O.

    1982-01-01

    This essay on collection development in academic libraries focuses on four issues: collection size, written collection development policies, involvement of teaching faculty in collection development, and the status of scholarly periodicals. Twenty references are listed. (EJS)

  9. Academic Freedom and Artistic Expression.

    Science.gov (United States)

    Stern, Carol Simpson

    1994-01-01

    Recent attempts to curtail artistic expression in colleges and universities, particularly in relation to federal funding, are examined and it is concluded that artistic expression merits protections of academic freedom similar to those accorded to intellectual expression. (Author/MSE)

  10. Exploring the academic invisible web

    OpenAIRE

    Lewandowski, Dirk

    2006-01-01

    The Invisible Web is often discussed in the academic context, where its contents (mainly in the form of databases) are of great importance. But this discussion is mainly based on some seminal research done by Sherman and Price (2001) and Bergman (2001), respectively. We focus on the types of Invisible Web content relevant for academics and the improvements made by search engines to deal with these content types. In addition, we question the volume of the Invisible Web as stated by Bergman. Ou...

  11. Exploring the academic invisible web

    OpenAIRE

    Lewandowski, Dirk; Mayr, Philipp

    2007-01-01

    Purpose: To provide a critical review of Bergman’s 2001 study on the Deep Web. In addition, we bring a new concept into the discussion, the Academic Invisible Web (AIW). We define the Academic Invisible Web as consisting of all databases and collections relevant to academia but not searchable by the general-purpose internet search engines. Indexing this part of the Invisible Web is central to scientific search engines. We provide an overview of approaches followed thus far. Design/methodol...

  12. Academic Performance and Behavioral Patterns

    OpenAIRE

    Kassarnig, Valentin; Mones, Enys; Bjerre-Nielsen, Andreas; Sapiezynski, Piotr; Lassen, David Dreyer; Lehmann, Sune

    2017-01-01

    Identifying the factors which influence academic performance is an essential part of educational research. Previous studies have documented the importance of personality traits, class attendance, and social network structure. However, because most of these analyses were based on a single behavioral aspect and/or small sample sizes, we lack a quantification of the interplay of these factors. Here, we infer the academic performance among a cohort of almost 1,000 freshmen based on data collected...

  13. Benchmarking in Academic Pharmacy Departments

    OpenAIRE

    Bosso, John A.; Chisholm-Burns, Marie; Nappi, Jean; Gubbins, Paul O.; Ross, Leigh Ann

    2010-01-01

    Benchmarking in academic pharmacy, and recommendations for the potential uses of benchmarking in academic pharmacy departments are discussed in this paper. Benchmarking is the process by which practices, procedures, and performance metrics are compared to an established standard or best practice. Many businesses and industries use benchmarking to compare processes and outcomes, and ultimately plan for improvement. Institutions of higher learning have embraced benchmarking practices to facilit...

  14. Relationship between egg weight, hatch weight and subsequent ...

    African Journals Online (AJOL)

    Three hundred (300) Fulani Ecotype (FE) chicken eggs collected from free ranged Fulani Ecotype chicken were used to study the effect of egg weight on hatch weight and subsequent body weight. Eggs were grouped into two according to their weight (small and medium) and incubated. Body weight of the chicks was ...

  15. A case study of high genetic loading and subsequent development ...

    African Journals Online (AJOL)

    became depressed and her school functioning declined even more. A child psychiatrist diagnosed a major depressive disorder and ADHD. She was prescribed citalopram 10 mg daily and methylphenidate. She became hyperactive on the antidepressant, which was subsequently discontinued. The methylphenidate was ...

  16. McGurk illusion recalibrates subsequent auditory perception

    NARCIS (Netherlands)

    Lüttke, C.S.; Ekman, M.; Gerven, M.A.J. van; Lange, F.P. de

    2016-01-01

    Visual information can alter auditory perception. This is clearly illustrated by the well-known McGurk illusion, where an auditory/aba/ and a visual /aga/ are merged to the percept of 'ada'. It is less clear however whether such a change in perception may recalibrate subsequent perception. Here we

  17. 27 CFR 479.66 - Subsequent transfer of firearms.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 3 2010-04-01 2010-04-01 false Subsequent transfer of firearms. 479.66 Section 479.66 Alcohol, Tobacco Products, and Firearms BUREAU OF ALCOHOL, TOBACCO, FIREARMS, AND EXPLOSIVES, DEPARTMENT OF JUSTICE FIREARMS AND AMMUNITION MACHINE GUNS, DESTRUCTIVE DEVICES...

  18. Risks associated with subsequent pregnancy after one caesarean ...

    African Journals Online (AJOL)

    The absolute risk of failed trial of vaginal birth after a cesarean was 45% (95% CI: 38.5, 51.5). Conclusion: Women who have one previous C.section face a markedly increased risk of repeat caesarean sections and feto.maternal complications in subsequent pregnancies. There is a need for doctors in Nigeria to be mindful of ...

  19. Effect of winter nutritional levels on subsequent growth of beef ...

    African Journals Online (AJOL)

    Effect of winter nutritional levels on subsequent growth of beef heifers in the Highland Sourveld of Natal. ... Teen 'n lae veebelading van 0,75 GVE/ha (vir die weiperiode) op somerveld, het verse betekenisvol (P < 0,01) meer in massa toegeneem vergeleke met 'n hoë veebelading (1,25 GVE/ha). Binne elk van die ...

  20. Fast Arc-Annotated Subsequence Matching in Linear Space

    DEFF Research Database (Denmark)

    Bille, Philip; Gørtz, Inge Li

    2010-01-01

    is deleted any arc with an endpoint in that base is also deleted. Arc-annotated strings where the arcs are "nested" are a natural model of RNA molecules that captures both the primary and secondary structure of these. The arc-preserving subsequence problem for nested arc-annotated strings is basic primitive...

  1. Maternal Obesity in Early Pregnancy and Subsequent Pregnancy ...

    African Journals Online (AJOL)

    Despite a rising prevalence worldwide, there is limited data on pregnancy outcome among African women with prepregnancy or early pregnancy obesity. This was a case-control study to determine the prevalence of maternal obesity in early pregnancy and compare the subsequent pregnancy outcome between 201 women ...

  2. The Differential Effect of Attentional Condition on Subsequent Vocabulary Development

    Science.gov (United States)

    Mohammed, Halah Abdulelah; Majid, Norazman Abdul; Abdullah, Tina

    2016-01-01

    This study addressed the potential methodological issues effect of attentional condition on subsequent vocabulary development from a different perspective, which addressed several potential methodological issues of previous research that have been based on psycholinguistic notion of second language learner as a limited capacity processor. The…

  3. Physical Restraint Initiation in Nursing Homes and Subsequent Resident Health

    Science.gov (United States)

    Engberg, John; Castle, Nicholas G.; McCaffrey, Daniel

    2008-01-01

    Purpose: It is widely believed that physical restraint use causes mental and physical health decline in nursing home residents. Yet few studies exist showing an association between restraint initiation and health decline. In this research, we examined whether physical restraint initiation is associated with subsequent lower physical or mental…

  4. Duration of exclusive breastfeeding and subsequent child feeding ...

    African Journals Online (AJOL)

    Objective: Mothers of young children in Ghana believe that breastfeeding exclusively for six months impairs subsequent introduction of other foods. The current study was designed to determine whether feeding adequacy among 9-23 months old children is influenced by duration of exclusive breastfeeding. Design: We ...

  5. Beliefs about Child Support Modification Following Remarriage and Subsequent Childbirth

    Science.gov (United States)

    Hans, Jason D.

    2009-01-01

    Framed by equity theory, fairness beliefs regarding child support modification to account for the financial impact of remarriage and subsequent childbirth were assessed. Based on a random sample of 407 Kentucky residents using a multiple segment factorial vignette approach, modification was supported by 57% of respondents following remarriage, but…

  6. Sustained mental workload does not affect subsequent sleep intensity

    NARCIS (Netherlands)

    de Bruin, EA; Beersma, DGM; Daan, S; Bruin, Eveline A. de

    Mental activity is a neglected factor in sleep research. The few investigations on sleep that manipulate prior mental activity are inconclusive with respect to the possible effects of mental activity on recovery. In the present study, the effects of two levels of mental activity on subsequent sleep

  7. Impact of Selection Bias on Estimation of Subsequent Event Risk.

    Science.gov (United States)

    Hu, Yi-Juan; Schmidt, Amand F; Dudbridge, Frank; Holmes, Michael V; Brophy, James M; Tragante, Vinicius; Li, Ziyi; Liao, Peizhou; Quyyumi, Arshed A; McCubrey, Raymond O; Horne, Benjamin D; Hingorani, Aroon D; Asselbergs, Folkert W; Patel, Riyaz S; Long, Qi

    2017-10-01

    Studies of recurrent or subsequent disease events may be susceptible to bias caused by selection of subjects who both experience and survive the primary indexing event. Currently, the magnitude of any selection bias, particularly for subsequent time-to-event analysis in genetic association studies, is unknown. We used empirically inspired simulation studies to explore the impact of selection bias on the marginal hazard ratio for risk of subsequent events among those with established coronary heart disease. The extent of selection bias was determined by the magnitudes of genetic and nongenetic effects on the indexing (first) coronary heart disease event. Unless the genetic hazard ratio was unrealistically large (>1.6 per allele) and assuming the sum of all nongenetic hazard ratios was bias was usually bias, the probability that a confidence interval included the true effect decreased (undercoverage) with increasing sample size because of increasing precision. Importantly, false-positive rates were not affected by selection bias. In most empirical settings, selection bias is expected to have a limited impact on genetic effect estimates of subsequent event risk. Nevertheless, because of undercoverage increasing with sample size, most confidence intervals will be over precise (not wide enough). When there is no effect modification by history of coronary heart disease, the false-positive rates of association tests will be close to nominal. © 2017 American Heart Association, Inc.

  8. Biological control of Aspergillus flavus growth and subsequent ...

    African Journals Online (AJOL)

    ONOS

    2010-07-05

    Jul 5, 2010 ... This study, therefore explored the potential use of certain biocontrol agents for the reduction of growth of toxigenic Aspergillus flavus and subsequent aflatoxin B1 (AFB1) production in sorghum. Among all the biocontrol agents tested, culture filtrate of Rhodococcus erythropolis completely inhibited the A.

  9. Incidence of pelvic organ prolapse repair subsequent to hysterectomy

    DEFF Research Database (Denmark)

    Lykke, Rune; Blaakær, Jan; Ottesen, Bent

    2017-01-01

    INTRODUCTION AND HYPOTHESIS: The aim of this study was to compare the incidence of subsequent pelvic organ prolapse (POP) repair in women following radical hysterectomy versus total abdominal hysterectomy. METHODS: From the Danish National Patient Registry, we collected data on all radical...

  10. Changes in job strain and subsequent weight gain

    DEFF Research Database (Denmark)

    Vesterlund, Gitte Kingo; Keller, Amélie Cléo; Heitmann, Berit Lilienthal

    2017-01-01

    Objective: Obesity as well as job strain is increasing, and job strain might contribute to weight gain. The objective of the current study was to examine associations between longitudinal alterations in the components of job strain and subsequent weight gain. Design: The study was designed...

  11. Chronic genital ulcer disease with subsequent development of ...

    African Journals Online (AJOL)

    HIV-seropositive persons are at increased risk of methicillin-resistant Staphylococcus aureus (MRSA). Genital ulcerative disease and sexually transmitted infection with subsequent MRSA infection in HIV-seropositive persons have been documented only once. We report a case of a 44-year-old man who presented to the ...

  12. Diet quality and academic performance.

    Science.gov (United States)

    Florence, Michelle D; Asbridge, Mark; Veugelers, Paul J

    2008-04-01

    Although the effects of nutrition on health and school performance are often cited, few research studies have examined the effect of diet quality on the academic performance of children. This study examines the association between overall diet quality and academic performance. In 2003, 5200 grade 5 students in Nova Scotia, Canada, and their parents were surveyed as part of the Children's Lifestyle and School-performance Study. Information on dietary intake, height, and weight and sociodemographic variables were linked to results of a provincial standardized literacy assessment. Diet Quality Index-International was used to summarize overall diet quality. Multilevel regression methods were used to examine the association between indicators of diet quality and academic performance while adjusting for gender and socioeconomic characteristics of parents and residential neighborhoods. Across various indicators of diet quality, an association with academic performance was observed. Students with decreased overall diet quality were significantly more likely to perform poorly on the assessment. Girls performed better than boys as did children from socioeconomically advantaged families. Children attending better schools and living in wealthy neighborhoods also performed better. These findings demonstrate an association between diet quality and academic performance and identify specific dietary factors that contribute to this association. Additionally, this research supports the broader implementation and investment in effective school nutrition programs that have the potential to improve student access to healthy food choices, diet quality, academic performance, and, over the long term, health.

  13. [Women's academic careers in medicine].

    Science.gov (United States)

    Schlichting, Ellen; Nielsen, Harriet Bjerrum; Fosså, Sophie Dorothea; Aasland, Olaf Gjerløw

    2007-08-23

    Few female doctors hold top academic positions at the University of Oslo. A working group was appointed by the Faculty of Medicine to investigate possible reasons for this and to come up with recommendations on how to increase the fraction of female professors. A questionnaire was sent to 875 medical graduates who had either completed or were taking a PhD at the University of Oslo. Two focus group interviews were also performed, one with female and one with male graduates. The questionnaire response rate was 42%. The genders did not differ concerning motivation to pursue academic careers, and they both wished to have better access to combined positions (academic and clinical work). Women needed more positive signals on being wanted as researchers. For women below 45 years of age, academic and clinical role models and a good network were considered to be especially important. Women emphasized the importance of equality at home and at work for pursuing an academic career more than men. The gender imbalance among medical professors will not resolve itself. Young women should be more actively identified and encouraged to pursue academic careers.

  14. Natural course of subsequent pregnancy after peripartum cardiomyopathy

    Directory of Open Access Journals (Sweden)

    Francisco Manes Albanesi Fº

    1999-07-01

    Full Text Available OBJECTIVE: To assess the effect of subsequent pregnancy after peripartum cardiomyopathy (PPCM on maternal and fetal outcome. METHODS: Prospective study of 34 patients with the diagnosis of PPCM (mean age= 26years. At the time of first diagnosis 5 were in NYHA functional class (FC II for heart failure, one in FC III and 28 in FC IV. After clinical treatment, patients were advised to avoid new pregnancies and a follow-up was obtained. RESULTS: There were 12 (35.3% subsequent pregnancies in patients (pt aged 19 to 44 years (mean 32, divided into two groups: GI: 6 pts who had normalized their heart size and GII: 6 pts with persistent cardiomegaly. GI had initially mild clinical manifestations ( 3 were in FC II, 1 in FC II and 2 in FC IV and complete recovery of cardiac function (FC I. A new pregnancy was well-tolerated in 5 (83.3%; 1 pt presented with preeclampsia, and progressed to FC II. Presently, 5 pt are in FC I and 1 in FC II. GII pts had more severe heart failure at the onset of PPCM (1 pt in FC II and 5 in FC IV; during follow-up, 4 pt were in FC I and 2 in FC II. A new pregnancy was well tolerated in all of them, but the eldest, who had had 2 pregnancies and had a progressive worsening of clinical status, dying 8 years after the last pregnancy and 13 years after the diagnosis of PPCM. The remaining 5 pt are still alive, 3 in FC I and 2 in FC II, with worsening of FC in 1. Subsequent pregnancies occurred 3-7 years after clinical treatment of PPCM and no fetal distress was observed. CONCLUSION: Subsequent pregnancies are well-tolerated after PPCM, but not devoid of risk. No fetal distress was observed. A minimum interval of 3 years after the recovery of function seems to be safe for subsequent pregnancies.

  15. Term induction of labor and subsequent preterm birth.

    Science.gov (United States)

    Levine, Lisa D; Bogner, Hillary R; Hirshberg, Adi; Elovitz, Michal A; Sammel, Mary D; Srinivas, Sindhu K

    2014-04-01

    Although the rate of inductions continues to rise, there is a paucity of data investigating subsequent pregnancy outcomes after induction. Our objective was to compare term inductions with term spontaneous labor and evaluate the rate of subsequent spontaneous preterm birth (sPTB). A retrospective cohort study of women with 2 consecutive deliveries from 2005 through 2010 was performed. Term inductions or term spontaneous labor in the index pregnancy was included, and those with a prior sPTB were excluded. Data were obtained through chart abstraction. The primary outcome was sPTB (Term inductions were less likely to have a subsequent sPTB compared with term spontaneous labor (6% vs 11%; odds ratio [OR], 0.49; 95% confidence interval, 0.29-0.81; P = .005). This remained after adjusting for confounders (adjusted OR, 0.55; P = .04). The sPTB risk depended on gestational age of index delivery. At 37-38.9 weeks, the sPTB rate after spontaneous labor was 24% vs 9% after induction (OR, 3.0; 95% confidence interval, 1.44-6.16; P = .003). This was not significant for 39-39.9 weeks (P = .2) or 40 weeks or longer (P = .8). Induction is not a risk factor for subsequent sPTB. Spontaneous labor, however, in the early term period is associated with subsequent sPTB. Further investigation among early term deliveries is warranted to evaluate the risk of sPTB and target interventions in this cohort. Copyright © 2014 Mosby, Inc. All rights reserved.

  16. Effects of internal heat generation, thermal radiation and buoyancy force on a boundary layer over a vertical plate with a convective surface boundary condition

    Directory of Open Access Journals (Sweden)

    Tasawar Hayat

    2011-09-01

    Full Text Available In this paper we analyse the effects of internal heat generation, thermal radiation and buoyancy force on the laminar boundary layer about a vertical plate in a uniform stream of fluid under a convective surface boundary condition. In the analysis, we assumed that the left surface of the plate is in contact with a hot fluid whilst a stream of cold fluid flows steadily over the right surface; the heat source decays exponentially outwards from the surface of the plate. The similarity variable method was applied to the steady state governing non-linear partial differential equations, which were transformed into a set of coupled non-linear ordinary differential equations and were solved numerically by applying a shooting iteration technique together with a sixth-order Runge–Kutta integration scheme for better accuracy. The effects of the Prandtl number, the local Biot number, the internal heat generation parameter, thermal radiation and the local Grashof number on the velocity and temperature profiles are illustrated and interpreted in physical terms. A comparison with previously published results on similar special cases showed excellent agreement.

  17. Noncognitive Predictors of Student Athletes' Academic Performance.

    Science.gov (United States)

    Simons, Herbert D.; Van Rheenen, Derek

    2000-01-01

    Examines the role of four noncognitive variables in predicting academic performance in 200 Division I athletes. Studies the noncognitive variables of athletic-academic commitment, feelings of being exploited, academic self-worth, self-handicapping excuses as well as several background and academic preparation variables. Finds all four noncognitive…

  18. Mainstreaming academic literacy teaching: Implications for how ...

    African Journals Online (AJOL)

    This article draws on research into the role of academic literacies within a range of disciplines and its implications for academic literacy teaching in Higher Education. The study explored ways of transforming current academic literacy teaching practices with a view to developing better synergy between the academic ...

  19. Academic Freedom: Its Nature, Extent and Value

    Science.gov (United States)

    Barrow, Robin

    2009-01-01

    Academic freedom does not refer to freedom to engage in any speech act, but to freedom to hold any belief and espouse it in an appropriately academic manner. This freedom belongs to certain institutions, rather than to individuals, because of their academic nature. Academic freedom should be absolute, regardless of any offence it may on occasion…

  20. Academic training: Applied superconductivity

    CERN Multimedia

    2007-01-01

    LECTURE SERIES 17, 18, 19 January from 11.00 to 12.00 hrs Council Room, Bldg 503 Applied Superconductivity : Theory, superconducting Materials and applications E. PALMIERI/INFN, Padova, Italy When hearing about persistent currents recirculating for several years in a superconducting loop without any appreciable decay, one realizes that we are dealing with a phenomenon which in nature is the closest known to the perpetual motion. Zero resistivity and perfect diamagnetism in Mercury at 4.2 K, the breakthrough during 75 years of several hundreds of superconducting materials, the revolution of the "liquid Nitrogen superconductivity"; the discovery of still a binary compound becoming superconducting at 40 K and the subsequent re-exploration of the already known superconducting materials: Nature discloses drop by drop its intimate secrets and nobody can exclude that the last final surprise must still come. After an overview of phenomenology and basic theory of superconductivity, the lectures for this a...

  1. Sleep and academic performance in undergraduates: a multi-measure, multi-predictor approach.

    Science.gov (United States)

    Gomes, Ana Allen; Tavares, Jos; de Azevedo, Maria Helena P

    2011-11-01

    The present study examined the associations of sleep patterns with multiple measures of academic achievement of undergraduate university students and tested whether sleep variables emerged as significant predictors of subsequent academic performance when other potential predictors, such as class attendance, time devoted to study, and substance use are considered. A sample of 1654 (55% female) full-time undergraduates 17 to 25 yrs of age responded to a self-response questionnaire on sleep, academics, lifestyle, and well-being that was administered at the middle of the semester. In addition to self-reported measures of academic performance, a final grade for each student was collected at the end of the semester. Univariate analyses found that sleep phase, morningness/eveningness preference, sleep deprivation, sleep quality, and sleep irregularity were significantly associated with at least two academic performance measures. Among 15 potential predictors, stepwise multiple regression analysis identified 5 significant predictors of end-of-semester marks: previous academic achievement, class attendance, sufficient sleep, night outings, and sleep quality (R(2)=0.14 and adjusted R(2)=0.14, F(5, 1234)= 40.99, p academic achievement and the remaining sleep variables as well as the academic, well-being, and lifestyle variables lost significance in stepwise regression. Together with class attendance, night outings, and previous academic achievement, self-reported sleep quality and self-reported frequency of sufficient sleep were among the main predictors of academic performance, adding an independent and significant contribution, regardless of academic variables and lifestyles of the students.

  2. THE ROLE OF ACADEMIC MOTIVATION AND ACADEMIC SELF CONCEPT IN STUDENT’S ACADEMIC ACHIEVEMENT

    OpenAIRE

    Kalaivani, M; Dr. V. Rajeswari

    2016-01-01

    Education is important to cultivate good values among the public in society. Education helps men to develop their life style. The ultimate goal of school is to educate young people to become responsible. Education is the complete development of individuality of the child so that the man can make an original contribution to human life according to the best of his capacity.. Both academic motivation and academic self-concept promote positive learning environment among the students. It is not ju...

  3. [The relationship between academic self-efficacy and academic burnout in medical students].

    Science.gov (United States)

    Lee, Su Hyun; Jeon, Woo Taek

    2015-03-01

    The purpose of this study was to examine the correlation between academic burnout and academic self-efficacy in medical students. The study group comprised 446 students in years 1 to 4 of medical school. They were asked to rate their academic burnout and academic self-efficacy on a scale. The data were analyzed by multivariate analysis of variance and regression analysis. Academic self-efficacy was correlated negatively with academic burnout explaining 37% of academic burnout. Academic self-efficacy (especially self-confidence) had the greatest effect on academic burnout. The implications of these results are discussed in terms of an evaluation and support system for students.

  4. Academic family health teams

    Science.gov (United States)

    Carroll, June C.; Talbot, Yves; Permaul, Joanne; Tobin, Anastasia; Moineddin, Rahim; Blaine, Sean; Bloom, Jeff; Butt, Debra; Kay, Kelly; Telner, Deanna

    2016-01-01

    Abstract Objective To explore patients’ perceptions of primary care (PC) in the early development of academic family health teams (aFHTs)—interprofessional PC teams delivering care where family medicine and other health professional learners are trained—focusing on patients’ perceptions of access and patients’ satisfaction with services. Design Self-administered survey. Setting Six aFHTs in Ontario. Participants Adult patients attending appointments and administrators at each of the aFHTs. Main outcome measures Answers to questions about access from the Primary Care Assessment Tool Adult Expanded Version, the Primary Care Assessment Survey, and research team questions. Results The response rate was 47.3% (1026 of 2167). The mean (SD) Primary Care Assessment Tool first-contact accessibility score was 2.28 (0.36) out of 4, with 96.5% of patients rating access less than 3, which was the minimum expected level of care. Two-thirds (66.6%) indicated someone from their aFHTs would definitely or probably see them the same day if they were sick, 56.8% could definitely or probably get advice quickly by telephone, and 14.5% indicated it was definitely or probably difficult to be seen by their primary health care provider (HCP). Additionally, 46.9% indicated they would like to get medical advice by e-mail. For a routine or follow-up visit, 73.4% would be willing to see another aFHT physician if their regular provider were unavailable, while only 48.3% would see a nonphysician HCP. If sick, 88.2% would see another aFHT physician and 55.2% would see a nonphysician HCP. Most (75.3%) were satisfied with access to their regular HCP. Conclusion Although patients are generally satisfied with care, there is room for improvement in access. Strategies are needed to enhance access to care, including addressing appropriate roles and scopes of practice for nonphysician HCPs. The accessibility challenges for aFHTs will likely affect new family physicians and other HCPs training in

  5. Academic dishonesty among Italian nursing students: A longitudinal study.

    Science.gov (United States)

    Macale, Loreana; Ghezzi, Valerio; Rocco, Gennaro; Fida, Roberta; Vellone, Ercole; Alvaro, Rosaria

    2017-03-01

    Considering the ethical issues related to nursing and that Ethics is an integral part of the nursing education in the degree course, one would suppose that academic dishonesty might be less frequent in nursing students than in students of other disciplines. However, several studies show that this trend of deceitful behaviour seems to be similar among the university nursing students and those of other disciplines. The aim of this study is to investigate the phenomenon of academic dishonesty in the classroom from a longitudinal perspective within a cohort of Italian nursing students. A non-experimental longitudinal design was used. All nursing students were recruited from the Nursing Science Bachelor Degree Program of a big Italian university in the centre of Italy and participants were part of an ongoing longitudinal research project which started in 2011 on nursing students' wellbeing. The results show that students get accustomed to taking academically deceitful actions. They come to consider their behaviours acceptable and normal, thereby stabilizing them, which increases the probability of stabilizing subsequent deceitful behaviours. The stability through time of academic cheating behaviours committed during higher education, within the study's timeframe, provides important perspectives into the establishment of rigorous standards of ethical and moral behaviours by the students. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Relationship of Perceived Stress, Perfectionism and Social Support with Students’ Academic Burnout and -Academic Performance

    Directory of Open Access Journals (Sweden)

    Pourseyyed SM

    2015-07-01

    Conclusion: Perceived stress has negative direct relationship with social support and positive direct relationship with academic burnout. Social support also has positive direct relationship with academic performance. Relationship of maladaptive perfectionism with academic burnout and also the relationship of adaptive perfectionism with academic performance is direct positive. Relationship of perceived stress with academic performance is indirect mediated by social support.

  7. Academic Governance Provided by Academic Boards within the Australian Higher Education Sector

    Science.gov (United States)

    Vilkinas, Tricia; Peters, Margaret

    2014-01-01

    Academic boards play a key role in the maintenance of quality standards and the provision of strategic leadership on academic issues. The current research investigated the role provided at present to Australian universities through their academic boards. All universities described their academic boards as their principal academic body. The…

  8. Academic Mobility, Transnational Identity Capital, and Stratification under Conditions of Academic Capitalism

    Science.gov (United States)

    Kim, Terri

    2017-01-01

    Academic mobility has existed since ancient times. Recently, however, academic mobility--the crossing of international borders by academics who then work "overseas"--has increased. Academics and the careers of academics have been affected by governments and institutions that have an interest in coordinating and accelerating knowledge…

  9. The Reluctant Academic: Early-Career Academics in a Teaching-Orientated University

    Science.gov (United States)

    Gale, Helen

    2011-01-01

    This paper is based on research into academic identities amongst early-career academics in a UK post-1992, teaching-orientated university. Literature around academic identity suggests five major academic roles: teaching, research, management, writing and networking. However, this appears to be a picture of an established mid-career academic in a…

  10. Towards an analysis of academic weblogs

    OpenAIRE

    Stuart, Keith

    2006-01-01

    This paper analyses both the communicative purposes and formal linguistic features of academic weblogs. An initial analysis of 496 weblogs in use within tertiary level institutions was reduced to an in-depth analysis of 39 academic weblogs (a corpus of 16 million words). The objective was to see how much variation there might be between traditional academic genres and academic weblogs. The initial hypothesis is that academic weblogs are far less formal and would favour greater use of lexico-g...

  11. ACADEMIC DISHONESTY AND WORKPLACE DISHONESTY. AN OVERVIEW

    OpenAIRE

    Octavian RUJOIU; Valentina RUJOIU

    2014-01-01

    It is known by many names...unethical behavior in higher education, academic fraud, academic misconduct. It takes many forms...plagiarism, cheating on tests or exams, cybercheating. But all describe the characteristics of the same phenomenon: academic dishonesty. It is met in all societies and in the academic environments since ancient times. The aim of this overview was to analyze the major studies and research having as central points of discussion academic dishonesty and workplace dishones...

  12. Academization of Danish semi-professionals

    DEFF Research Database (Denmark)

    Bøje, Jakob Ditlev

    2012-01-01

    Academization is a phenomenon which plays an increasing role in the training programmes for the semi-professions. In Denmark academization has been researched from a predominantly student perspective, as an analysis of how abstract forms of knowledge dominate competencies for care and nursing among...... female students. This article examines academization as a discursive phenomenon. It shows how academization has been produced through historical developments of the educational policies surrounding the semiprofessional schools. Furthermore, the article discusses what consequences academization may have...

  13. Medical abortion and the risk of subsequent adverse pregnancy outcomes

    DEFF Research Database (Denmark)

    Virk, Jasveer; Zhang, Jun; Olsen, Jørn

    2007-01-01

    BACKGROUND: The long-term safety of surgical abortion in the first trimester is well established. Despite the increasing use of medical abortion (abortion by means of medication), limited information is available regarding the effects of this procedure on subsequent pregnancies. METHODS: We...... identified all women living in Denmark who had undergone an abortion for nonmedical reasons between 1999 and 2004 and obtained information regarding subsequent pregnancies from national registries. Risks of ectopic pregnancy, spontaneous abortion, preterm birth (at ... weight (abortion were compared with risks in women who had had a first-trimester surgical abortion. RESULTS: Among 11,814 pregnancies in women who had had a previous first-trimester medical abortion (2710 women...

  14. Association Between Psychotic Experiences and Subsequent Suicidal Thoughts and Behaviors

    DEFF Research Database (Denmark)

    Bromet, Evelyn J; Nock, Matthew K; Saha, Sukanta

    2017-01-01

    Importance: Community-based studies have linked psychotic experiences (PEs) with increased risks of suicidal thoughts and behaviors (STBs). However, it is not known if these associations vary across the life course or if mental disorders contribute to these associations. Objective: To examine...... the temporal association between PEs and subsequent STBs across the life span as well as the influence of mental disorders (antecedent to the STBs) on these associations. Design, Setting, and Participants: A total of 33 370 adult respondents across 19 countries from the World Health Organization World Mental...... Health Surveys were assessed for PEs, STBs (ie, ideation, plans, and attempts), and 21 DSM-IV mental disorders. Discrete-time survival analysis was used to investigate the associations of PEs with subsequent onset of STBs. Main Outcomes and Measures: Prevalence and frequency of STBs with PEs, and odds...

  15. Personal commentary: monitoring subsequent pregnancy in recovered peripartum cardiomyopathy mothers.

    Science.gov (United States)

    Fett, James D

    2009-12-01

    Peripartum cardiomyopathy (PPCM) is defined as the first appearance of systolic heart failure in a previously healthy woman during the last month of pregnancy or up to 6 months postpartum. Both planned and unplanned pregnancies may occur in recovered and non-recovered PPCM mothers, requiring careful counseling and management strategies. Previous studies indicate that relapse of heart failure in post-PPCM pregnancies is always a possibility, even in recovered PPCM mothers. The risk of relapse is high when the left ventricular ejection fraction is less than 0.50, and should be considered a relative contraindication to subsequent pregnancy. There are not yet established protocols for monitoring subsequent pregnancies in those who once had PPCM, and few medical articles with guidelines. This personal commentary contains parameters that have been found useful to contribute to safer monitoring with improved outcomes.

  16. Learning increases human electroencephalographic coherence during subsequent slow sleep oscillations.

    Science.gov (United States)

    Mölle, Matthias; Marshall, Lisa; Gais, Steffen; Born, Jan

    2004-09-21

    Learning is assumed to induce specific changes in neuronal activity during sleep that serve the consolidation of newly acquired memories. To specify such changes, we measured electroencephalographic (EEG) coherence during performance on a declarative learning task (word pair associations) and subsequent sleep. Compared with a nonlearning control condition, learning performance was accompanied with a strong increase in coherence in several EEG frequency bands. During subsequent non-rapid eye movement sleep, coherence only marginally increased in a global analysis of EEG recordings. However, a striking and robust increase in learning-dependent coherence was found when analyses were performed time-locked to the occurrence of slow oscillations (learning in the slow-oscillatory, delta, slow-spindle, and gamma bands. The findings identify the depolarizing phase of the slow oscillations in humans as a time period particularly relevant for a reprocessing of memories in sleep.

  17. The Cognitive and Academic Benefits of Music to Children: Facts and Fiction

    Science.gov (United States)

    Crncec, Rudi; Wilson, Sarah J.; Prior, Margot

    2006-01-01

    There is considerable interest in the potential non-musical cognitive and academic benefits of music listening and instruction to children. This report describes three lines of research relevant to this issue, namely, the effects of: (1) focused music listening on subsequent task performance (the Mozart effect); (2) music instruction; and (3)…

  18. Work-Life Balance among academic staff of the University of Lagos ...

    African Journals Online (AJOL)

    Work-life balance is associated with the maintenance of stability in both one's professional and personal life. It is key to the welfare and, subsequently, job satisfaction and productivity of employees. It is against this understanding that this study surveyed the way academic staff of the University of Lagos perceive and pursue ...

  19. Bringing Public Engagement into an Academic Plan and Its Assessment Metrics

    Science.gov (United States)

    Britner, Preston A.

    2012-01-01

    This article describes how public engagement was incorporated into a research university's current Academic Plan, how the public engagement metrics were selected and adopted, and how those processes led to subsequent strategic planning. Some recognition of the importance of civic engagement has followed, although there are many areas in which…

  20. Self-Concept and Academic Achievement: A Meta-Analysis of Longitudinal Relations

    Science.gov (United States)

    Huang, Chiungjung

    2011-01-01

    The relation between self-concept and academic achievement was examined in 39 independent and longitudinal samples through the integration of meta-analysis and path analysis procedures. For relations with more than 3 independent samples, the mean observed correlations ranged from 0.20 to 0.27 between prior self-concept and subsequent academic…