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Sample records for retention understanding experiments

  1. Understanding Health Workers’ Job Preferences to Improve Rural Retention in Timor-Leste: Findings from a Discrete Choice Experiment

    PubMed Central

    Smitz, Marc-Francois; Witter, Sophie; Lemiere, Christophe; Eozenou, Patrick Hoang-Vu; Lievens, Tomas; Zaman, Rashid U.; Engelhardt, Kay; Hou, Xiaohui

    2016-01-01

    Background Timor-Leste built its health workforce up from extremely low levels after its war of independence, with the assistance of Cuban training, but faces challenges as the first cohorts of doctors will shortly be freed from their contracts with government. Retaining doctors, nurses and midwives in remote areas requires a good understanding of health worker preferences. Methods The article reports on a discrete choice experiment (DCE) carried out amongst 441 health workers, including 173 doctors, 150 nurses and 118 midwives. Qualitative methods were conducted during the design phase. The attributes which emerged were wages, skills upgrading/specialisation, location, working conditions, transportation and housing. Findings One of the main findings of the study is the relative lack of importance of wages for doctors, which could be linked to high intrinsic motivation, perceptions of having an already highly paid job (relative to local conditions), and/or being in a relatively early stage of their career for most respondents. Professional development provides the highest satisfaction with jobs, followed by the working conditions. Doctors with less experience, males and the unmarried are more flexible about location. For nurses and midwives, skill upgrading emerged as the most cost effective method. Conclusions The study is the first of its kind conducted in Timor-Leste. It provides policy-relevant information to balance financial and non-financial incentives for different cadres and profiles of staff. It also augments a thin literature on the preferences of working doctors (as opposed to medical students) in low and middle income countries and provides insights into the ability to instil motivation to work in rural areas, which may be influenced by rural recruitment and Cuban-style training, with its emphasis on community service. PMID:27846242

  2. Understanding Recruitment and Retention in Neurological Research

    PubMed Central

    Newberry, Alyssa; Sherwood, Paula; Hricik, Allison; Bradley, Sarah; Kuo, Jean; Crago, Elizabeth; Hoffman, Leslie A.; Given, Barbara A.

    2010-01-01

    Cognitive deficits in participants and the abrupt and traumatic way in which many neurological conditions present are two examples of the unique challenges in recruiting and retaining subjects with neurological injury for research studies. The purpose of this investigation was to identify obstacles to recruitment and retention in three ongoing research studies. These studies involve persons with neurological disorders across the continuum of care, from those newly diagnosed and with emergent presentation to those with more established, chronic neurological conditions. For the purpose of this analysis, we evaluated the effectiveness of the strategies employed to improve participation rates. The first study was an NIH funded project designed to identify biomarkers of vasospasm in persons (N=496) with aneurysmal subarachnoid hemorrhage (SAH) who presented to the neurovascular intensive care unit (NINR, RO1 NR004339). The purpose of the second study was to examine bio-behavioral interactions in family caregivers (N=59) of persons with a primary malignant brain tumor (PMBT) recruited in the community setting. The third project involved recruiting persons (N=1019) within an outpatient neurosurgical center to participate in a research registry. To determine differential effectiveness of strategies, consent and attrition rates were calculated at serial points over time in three studies and recruitment and retention strategies were compared. Sentinel time points in participants' disease trajectories played a key role in determining whether those who were approached to participate gave consent and were retained, particularly in the studies involving persons with aneurysmal SAH (consent = 85%; retention = 89%) and persons with PMBTs and their caregivers (consent = 68%; retention = 83%). In addition, several specific recruiter and interviewer training techniques were associated with higher recruitment and retention. Targeted strategies to improve participation rates are vital

  3. Understanding Retention in US Graduate Programs by Student Nationality

    ERIC Educational Resources Information Center

    Crede, Erin; Borrego, Maura

    2014-01-01

    The purpose of this study is to better understand the differences in selected retention constructs by student nationality in US graduate programs. Surveys administered at four universities across the United States during fall 2010 resulted in responses from 685 PhD students from six international regions. Using univariate ANOVA, responses were…

  4. The Retention of Meaningful Understanding of Meiosis and Genetics.

    ERIC Educational Resources Information Center

    Cavallo, Ann Liberatore

    This study investigated the retention of meaningful understanding of the biological topics of meiosis, the Punnett square method and the relations between these two topics. This study also explored the predictive influence of students' general tendency to learn meaningfully or by rote (meaningful learning orientation), prior knowledge of meiosis,…

  5. Toward a mechanistic understanding of the effect of biochar addition on soil water retention

    NASA Astrophysics Data System (ADS)

    Yi, S.; Chang, N.; Guo, M.; Imhoff, P. T.

    2014-12-01

    Biochar (BC) is a carbon-rich product produced by thermal degradation of biomass in an oxygen-free environment, whose application to sediment is said to improve water retention. However, BC produced from different feedstocks and pyrolyzed at different temperatures have distinct properties, which may alter water retention in ways difficult to predict a priori. Our goal is to develop a mechanistic understanding of BC addition on water retention by examining the impact of BC from two feedstocks, poultry litter (PL) and hardwood (HW), on the soil-water retention curves (SWRC) of a uniform sand and a sandy loam (SL). For experiments with sand, BC and sand were sieved to the same particle size (~ 0.547 mm) to minimize effects of BC addition on particle size distribution. Experiments with SL contained the same sieved BC. PL and HW bicohars were added at 2 and 7% (w/w), and water retention was measured from 0 to -4.38 × 106 cm-H2O. Both BCs increased porosities for sand and SL, up to 39 and 13% for sand and SL, respectively, with 7% HW BC addition. The primary cause for these increases was the internal porosity of BC particles. While the matric potential for air-entry was unchanged with BC addition, BC amendment increased water retention for sand and SL in the capillary region (0 to -15,000 cm-H2O) by an average of 26 and 33 % for 7% PL and HW BC in sand, respectively, but only 7 and 14 % for 7% PL and HW BC in SL. The most dramatic influence of BC amendment on water retention occurred in the adsorption region (< -15,000 cm-H2O), where water retention increased by a factor of 11 and 22 for 7% PL and HW BC in sand, respectively, but by 140 and 190 % for 7% PL and HW BC in SL, respectively. The impact of BC on water retention in these sediments is explained primarily by the additional surface area and internal porosity of PL and HW BC particles. van Genuchten (VG) models were fitted to the water retention data. For SL where the impact of BC addition on water retention was

  6. Understanding customer experience.

    PubMed

    Meyer, Christopher; Schwager, Andre

    2007-02-01

    Anyone who has signed up for cell phone service, attempted to claim a rebate, or navigated a call center has probably suffered from a company's apparent indifference to what should be its first concern: the customer experiences that culminate in either satisfaction or disappointment and defection. Customer experience is the subjective response customers have to direct or indirect contact with a company. It encompasses every aspect of an offering: customer care, advertising, packaging, features, ease of use, reliability. Customer experience is shaped by customers' expectations, which largely reflect previous experiences. Few CEOs would argue against the significance of customer experience or against measuring and analyzing it. But many don't appreciate how those activities differ from CRM or just how illuminating the data can be. For instance, the majority of the companies in a recent survey believed they have been providing "superior" experiences to customers, but most customers disagreed. The authors describe a customer experience management (CEM) process that involves three kinds of monitoring: past patterns (evaluating completed transactions), present patterns (tracking current relationships), and potential patterns (conducting inquiries in the hope of unveiling future opportunities). Data are collected at or about touch points through such methods as surveys, interviews, focus groups, and online forums. Companies need to involve every function in the effort, not just a single customer-facing group. The authors go on to illustrate how a cross-functional CEM system is created. With such a system, companies can discover which customers are prospects for growth and which require immediate intervention.

  7. A Look into Students' Retention of Acquired Nature of Science Understandings

    ERIC Educational Resources Information Center

    Khishfe, Rola

    2015-01-01

    Having the learning and retention of science content and skills as a goal of scientific literacy, it is significant to study the issue of retention as it relates to teaching and learning about nature of science (NOS). Then, the purpose of this study was to investigate the development of NOS understandings of students, and the retention of these…

  8. Understanding Teacher Attraction and Retention Drivers: Addressing Teacher Shortages

    ERIC Educational Resources Information Center

    Ashiedu, Jennifer A.; Scott-Ladd, Brenda D.

    2012-01-01

    The attraction and retention of teachers is a problem faced by schools worldwide and possibly more so in the public sector. One possible solution to this problem is likely to be better targeting of attraction and retention drivers of value to teachers. This paper presents the findings from a qualitative study conducted in Australia. The study used…

  9. Retention in STEM: Understanding the Effectiveness of Science Posse

    NASA Astrophysics Data System (ADS)

    Godsoe, Kimberly

    One of the major areas of debate in higher education is how to best support underrepresented racial minority students in their study of Science, Technology, Engineering, and Math. In 2008, Brandeis University began a new program in conjunction with the Posse Foundation for students interested in studying science at the college-level. The research used a mixed methods design. A detailed quantitative analysis was conducted to understand how being part of Science Posse impacted the probability of doing well in initial science classes, influenced perceptions of the difficulty of studying science, and predicted the probability of majoring in STEM at Brandeis. The qualitative data was drawn from 89 student interviews, including 38 Science Posse Scholars, 24 students from backgrounds similar to the Scholars, and 25 students from well-resourced families. The qualitative analysis demonstrated how students had been exposed to the sciences prior to enrollment, how they navigated the sciences at Brandeis, and how they demonstrated resilience when science becomes challenging. This research study had four key findings. The first was in the quantitative analysis which demonstrated that Science Posse Scholars experience strong feelings of doubt about their academic abilities; based on previous research, this should have resulted in their not declaring majors in STEM disciplines. Instead, Science Posse Scholars were more likely to earn a B+ or above in their entry level science courses and declare a major in a STEM discipline, even when factors such as math and verbal SAT scores were included in the analysis. The second finding was in the qualitative analysis, which demonstrated that the cohort model in which Science Posse Scholars participate was instrumental to their success. The third finding was that students who attended academically less rigorous high schools could succeed in the sciences at a highly selective research institution such as Brandeis without academic remediation

  10. A Look into Students' Retention of Acquired Nature of Science Understandings

    NASA Astrophysics Data System (ADS)

    Khishfe, Rola

    2015-07-01

    Having the learning and retention of science content and skills as a goal of scientific literacy, it is significant to study the issue of retention as it relates to teaching and learning about nature of science (NOS). Then, the purpose of this study was to investigate the development of NOS understandings of students, and the retention of these understandings four months after being acquired through explicit reflective instruction in relation to two contexts. Participants were 24 tenth-grade students at a private high school in a city in the Middle East. Explicit NOS instruction was addressed within a six-week unit about genetic engineering. Three NOS aspects were integrated and dispersed across the unit. A questionnaire, together with semi-structured interviews, was administered as pre-, post-, and delayed post-test to assess the retention of participants' NOS understandings. The questionnaire had two open-ended scenarios addressing controversial socioscientific issues about genetically modified food and water fluoridation. Results showed that most students improved their naïve understandings of NOS in relation to the two contexts following the six-week unit with the explicit NOS instruction. However, these newly acquired NOS understandings were not retained by all students four months after instruction. Many of the students reverted back to their earlier naïve understandings. Conclusions about the factors facilitating the process of retention as the orientation to meaningful learning and the prolonged exposure to the domain were discussed in relation to practical implications in the classroom.

  11. Identifiability of diffusion and retention parameters of anionic tracers from the diffusion and retention (DR) experiment

    NASA Astrophysics Data System (ADS)

    Yi, Shuping; Samper, Javier; Naves, Acacia; Soler, Josep M.

    2012-06-01

    SummaryIn situ diffusion experiments in low-permeability rocks are performed to study radionuclide diffusion and sorption and investigate scale effects. They are carried out in a packed-off interval of a borehole having a circulation system in which tracers are injected and allowed to diffuse into the rock. Tracer concentrations are monitored at the tracer interval during the experiment (dilution data) and measured at the end of the experiment in rock cores (overcoring data). The interpretation of in situ diffusion experiments in clay formations is challenging due to the influence of the filter, the gap between the filter and the borehole wall and the borehole disturbed zone (BDZ). The impact of the filter, the gap and the BDZ on the estimates of the accessible porosity and the effective diffusion, De, of the rock in the presence of random noise has been evaluated for the anionic tracers with synthetic experiments having the geometry and parameters of the in situ diffusion and retention (DR) experiment performed on Opalinus clay. The component of De of the clay parallel to the bedding can be estimated properly from dilution data when the standard deviation of the noise of the data is smaller than 0.05, but the component of De normal to the bedding cannot be estimated from dilution data. On the other hand, both components of De can be estimated properly from noisy overcoring data. Although the parameters of the BDZ and the undisturbed clay cannot be estimated simultaneously from noisy dilution data, they can be estimated from noisy overcoring data when the standard deviation of the noise is smaller than 0.05. Parameter estimation errors are large when the assumption about the BDZ is incorrect. The uncertainties in the De of the filter and in the volume of the circulation system have a noticeable impact on the estimates of the diffusion and porosity of the clay derived from dilution data. On the other hand, acceptable parameter estimates are obtained from overcoring

  12. Background or Experience? Using Logistic Regression to Predict College Retention

    ERIC Educational Resources Information Center

    Synco, Tracee M.

    2012-01-01

    Tinto, Astin and countless others have researched the retention and attrition of students from college for more than thirty years. However, the six year graduation rate for all first-time full-time freshmen for the 2002 cohort was 57%. This study sought to determine the retention variables that predicted continued enrollment of entering freshmen…

  13. Experiment poseidon: Elemental iodine retention in water pools

    SciTech Connect

    Guentay, S.

    1990-01-01

    Although gaseous fraction of iodine is expected to be small in quantity compared with its other forms such as CsI, because of its radiological consequence, removal of elemental iodine vapor from the gas bubbles in water pools defines an important boundary condition for the severe-accident scenarios that involve water pools. The Muehleberg nuclear power plant (a boiling water reactor Mark 1 type) in Switzerland has a unique feature, namely, a second suppression pool surrounding the reactor building in addition to the regular pressure suppression pool. For those hypothetical accident scenarios that involve the second pool, scrubbing in the second suppression pool would ultimately determine the magnitude and constitution of the release. An experimental program, pool scrubbing effect on iodine decontamination (POSEIDON), was initiated at Paul Scherrer Institute (PSI) in Switzerland in 1987 to provide a data base on gaseous iodine scrubbing. Bubbles containing elemental iodine vapor and nitrogen as the carrier gas are generated using certain sized orifices immersed in a water pool. Objectives of the experimental program are defined as (a) to understand the iodine removal phenomena from bubbles and (b) to provide a data base for iodine retention under controlled boundary conditions for the development and verification of the BUSCA-PSI pool scrubbing code.

  14. Retention and Mentorship of Minority Students via Undergraduate Internship Experiences

    NASA Astrophysics Data System (ADS)

    Cooper, P.

    2004-12-01

    The School of Ocean and Earth Science and Technology at the University of Hawaii is undertaking an Undergraduate Research Internship project to address the lack of full representation of women and underrepresented minorities in the geosciences. The overarching educational objective is to provide education and career development guidance and opportunities for students from underrepresented minorities. In collaboration with industry partners, we hope to prepare undergraduate students for life and careers in today's complex and dynamic technological world by encouraging them to attain high standards in the geosciences, thereby enabling them to compete successfully for positions in graduate programs. To achieve his goal, the project focuses on the following objectives: (1) Creating a high-quality integrated on-campus teaching and off-campus learning environment, and (2) providing an intensive introduction to geoscience careers through the guidance of experienced faculty and workplace mentors. The program will start small, collaborating with one or two companies over the next two years, offering paid summer internships. Opportunities for students include participation in geoscience-related research, obtaining experience in interpreting observations and providing information to end-users, working to improve technology and field methods, and developing the expertise to maintain, operate and deploy equipment. Program participants are assigned individual projects that relate to their academic majors, their career goals, and the ongoing research missions of our industry partners. In addition to their research activities, participants attend a series of seminars and tours dealing with current topics in geoscience to expose them to the wide variety of scientific and technical activities that occur in the workplace. The expected outcomes of this experience will be scientific growth and career development. Given that a very small percentage of all students go on to graduate

  15. Mechanisms of nitrogen retention in forest ecosystems - A field experiment

    NASA Technical Reports Server (NTRS)

    Vitousek, P. M.; Matson, P. A.

    1984-01-01

    Intensive forest management led to elevated losses of nitrogen from a recently harvested loblolly pine plantation in North Carolina. Measurements of nitrogen-15 retention in the field demonstrated that microbial uptake of nitrogen during the decomposition of residual organic material was the most important process retaining nitrogen. Management practices that remove this material cause increased losses of nitrogen to aquatic ecosystems and the atmosphere.

  16. Children's understanding and experience of mixed emotions.

    PubMed

    Larsen, Jeff T; To, Yen M; Fireman, Gary

    2007-02-01

    Though some models of emotion contend that happiness and sadness are mutually exclusive in experience, recent findings suggest that adults can feel happy and sad at the same time in emotionally complex situations. Other research has shown that children develop a better conceptual understanding of mixed emotions as they grow older, but no research has examined children's actual experience of mixed emotions. To examine developmental differences in the experience of mixed emotions, we showed children ages 5 to 12 scenes from an animated film that culminated with a father and daughter's bittersweet farewell. In subsequent interviews, older children were more likely than younger children to report experiencing mixed emotions. These results suggest that in addition to having a better conceptual understanding of mixed emotions, older children are more likely than younger children to actually experience mixed emotions in emotionally complex situations.

  17. Students' Understanding of Stern Gerlach Experiment

    SciTech Connect

    Zhu Guangtian; Singh, Chandralekha

    2009-11-05

    The Stern Gerlach experiment has played a central role in the discovery of spin angular momentum and it has also played a pivotal role in elucidating foundational issues in quantum mechanics. Here, we discuss investigation of students' difficulties related to the Stern Gerlach experiment by giving written tests and interviewing advanced undergraduate and graduate students in quantum mechanics. We also discuss preliminary data that suggest that the Quantum Interactive Learning Tutorial (QuILT) related to the Stern Gerlach experiment is helpful in improving students' understanding of these concepts.

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

    NASA Astrophysics Data System (ADS)

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

    2013-12-01

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

  19. Addressing Student Success and Retention in STEM Majors Through Strategic Curriculum Pathways and Early Research Experiences

    NASA Astrophysics Data System (ADS)

    Jaspersohn, Robert P.

    In this dissertation we discuss a common first-year STEM curriculum pathway for undergraduate students majoring in science, math, or engineering, and a modification to this curriculum pathway that has been implemented, based on students' needs prior to enrollment. The intent is increasing student retention and success in the university and in STEM. The effects of the modification on student success, progression, retention and persistence are assessed, specifically. Second year retention in the university for the students who went through the modification has increased by 5%. Alternate non-traditional pathways within the first year physics laboratory experience can be introduced to address student needs.

  20. Experiments for understanding soil erosion processes

    NASA Astrophysics Data System (ADS)

    Seeger, Manuel

    2015-04-01

    Soil erosion processes are usually quantified by observation and measurement of their related forms. Rill, and gullies, moulds or sediment sinks are often used to estimate the soil loss. These forms are generally related directly to different types of processes, thus are also used to identify the dominant processes on a certain type of land-use. Nevertheless, the direct observation of erosion processes is constrained by their temporal and spatial erratic occurrence. As a consequence, the process understanding is generally deduced by analogies. Another possibility is to reproduce processes in experiments in both, the lab and in the field. Laboratory experiments are implemented when we want to have full control over all parameters we think are relevant for the process in our focus. So are very useful for identification of parameters influencing processes and their intensities, but also as physical models of the processes and process interactions in our focus. Therefore, we can use them to verify our concepts, and to define relevant parameters. Field experiments generally only simulate with controlled driving forces, this is the rain or the runoff, but dealing with the uncertainty of our study object, the soil. This enables two things: 1) similar as with lab experiments, we are able to identify processes and process interactions and so, to get a deeper understanding of soil erosion; 2) experiments are suitable for providing data about singular processes in the field and thus, to provide data suitable for model parametrisation and calibration. These may be quantitative data about erodibility or soil resistance, sediment detachment or transport. The Physical Geography Group at Trier University has a long lasting experience in the application of experiments in soil erosion research in the field, and has become lead in the further development conception and of devices and procedures to investigate splash detachment and initial transport of soil particles by wind and water

  1. Revisited reaction-diffusion model of thermal desorption spectroscopy experiments on hydrogen retention in material

    SciTech Connect

    Guterl, Jerome Smirnov, R. D.; Krasheninnikov, S. I.

    2015-07-28

    Desorption phase of thermal desorption spectroscopy (TDS) experiments performed on tungsten samples exposed to flux of hydrogen isotopes in fusion relevant conditions is analyzed using a reaction-diffusion model describing hydrogen retention in material bulk. Two regimes of hydrogen desorption are identified depending on whether hydrogen trapping rate is faster than hydrogen diffusion rate in material during TDS experiments. In both regimes, a majority of hydrogen released from material defects is immediately outgassed instead of diffusing deeply in material bulk when the evolution of hydrogen concentration in material is quasi-static, which is the case during TDS experiments performed with tungsten samples exposed to flux of hydrogen isotopes in fusion related conditions. In this context, analytical expressions of the hydrogen outgassing flux as a function of the material temperature are obtained with sufficient accuracy to describe main features of thermal desorption spectra (TDSP). These expressions are then used to highlight how characteristic temperatures of TDSP depend on hydrogen retention parameters, such as trap concentration or activation energy of detrapping processes. The use of Arrhenius plots to characterize retention processes is then revisited when hydrogen trapping takes place during TDS experiments. Retention processes are also characterized using the shape of desorption peaks in TDSP, and it is shown that diffusion of hydrogen in material during TDS experiment can induce long desorption tails visible aside desorption peaks at high temperature in TDSP. These desorption tails can be used to estimate activation energy of diffusion of hydrogen in material.

  2. Broadening the Learning Community Experience: An Outdoor Orientation Program's Impact on Engagement, Persistence, and Retention

    ERIC Educational Resources Information Center

    Nolan, Christy David

    2013-01-01

    The Keystone Learning Community was implemented by the Department of Campus Recreation to address retention at the institution. This learning community for incoming freshmen consists of two phases. Phase I is as an outdoor orientation program that includes a three day, two night canoeing and camping experience lead by upperclassmen leaders.…

  3. Evaluation of Gas Retention in Waste Simulants: Tall Column Experiments

    SciTech Connect

    Schonewill, Philip P.; Gauglitz, Phillip A.; Shimskey, Rick W.; Denslow, Kayte M.; Powell, Michael R.; Boeringa, Gregory K.; Bontha, Jagannadha R.; Karri, Naveen K.; Fifield, Leonard S.; Tran, Diana N.; Sande, Susan; Heldebrant, David J.; Meacham, Joseph E.; Smet, Dave; Bryan, Wesley E.; Calmus, Ronald B.

    2014-05-16

    Gas generation in Hanford’s underground waste storage tanks can lead to gas accumulation within the layer of settled solids (sludge) at the tank bottom. The gas, which typically has hydrogen as the major component together with other flammable species, is formed principally by radiation-driven chemical reactions. Accumulation of these gases within the sludge in a waste tank is undesirable and limits the amount of tank volume for waste storage. Further, accumulation of large amounts of gas in the sludge may potentially result in an unacceptable release of the accumulated gas if the sludge-layer density is reduced to less than that of the overlying sludge or that of the supernatant liquid. Rapid release of large amounts of flammable gases could endanger personnel and equipment near the tank. For this reason, a thorough understanding of the circumstances that can lead to a potentially problematic gas accumulation in sludge layers is needed. To respond to this need, the Deep Sludge Gas Release Event Program (DSGREP) was commissioned to examine gas release behavior in sludges.

  4. Using 3D Printers to Model Earth Surface Topography for Increased Student Understanding and Retention

    NASA Astrophysics Data System (ADS)

    Thesenga, David; Town, James

    2014-05-01

    In February 2000, the Space Shuttle Endeavour flew a specially modified radar system during an 11-day mission. The purpose of the multinational Shuttle Radar Topography Mission (SRTM) was to "obtain elevation data on a near-global scale to generate the most complete high-resolution digital topographic database of Earth" by using radar interferometry. The data and resulting products are now publicly available for download and give a view of the landscape removed of vegetation, buildings, and other structures. This new view of the Earth's topography allows us to see previously unmapped or poorly mapped regions of the Earth as well as providing a level of detail that was previously unknown using traditional topographic mapping techniques. Understanding and appreciating the geographic terrain is a complex but necessary requirement for middle school aged (11-14yo) students. Abstract in nature, topographic maps and other 2D renderings of the Earth's surface and features do not address the inherent spatial challenges of a concrete-learner and traditional methods of teaching can at times exacerbate the problem. Technological solutions such as 3D-imaging in programs like Google Earth are effective but lack the tactile realness that can make a large difference in learning comprehension and retention for these young students. First developed in the 1980's, 3D printers were not commercial reality until recently and the rapid rise in interest has driven down the cost. With the advent of sub US1500 3D printers, this technology has moved out of the high-end marketplace and into the local office supply store. Schools across the US and elsewhere in the world are adding 3D printers to their technological workspaces and students have begun rapid-prototyping and manufacturing a variety of projects. This project attempted to streamline the process of transforming SRTM data from a GeoTIFF format by way of Python code. The resulting data was then inputted into a CAD-based program for

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

    ERIC Educational Resources Information Center

    Fisher, Molly H.; Royster, David

    2016-01-01

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

  6. "Making the Difficult Choice": Understanding Georgia's Test-Based Grade Retention Policy in Reading

    ERIC Educational Resources Information Center

    Huddleston, Andrew P.

    2015-01-01

    The author uses Bourdieu's concepts of field, capital, and habitus to analyze how students, parents, teachers, and administrators are responding to Georgia's test-based grade retention policy in reading at one Georgia elementary school. In this multiple case study, the author interviewed, observed, and collected documents regarding ten fifth…

  7. Peeling the onion: understanding others' lived experience.

    PubMed

    Miles, Maureen; Chapman, Ysanne; Francis, Karen

    2015-01-01

    Society and some healthcare professionals often marginalise pregnant women who take illicit substances. Midwives who care for these women are often viewed as working on the edge of society. This research aimed to examine the lived experiences of midwives who care for pregnant women who take illicit drugs. A phenomenological study informed by Heidegger, Gadamer and Merleau-Ponty was chosen to frame these lived experiences. Using face-to-face interviews, data were collected from 12 midwives making a difference, establishing partnerships and letting go and refining practice. Lived experiences are unique and can be difficult, intangible and couched in metaphor and difficult to grasp. This paper aims to discuss lived experience and suggests that like an onion, several layers have to be peeled away before meaning can be exposed; each cover reveals another layer beneath that is different from before and different from the next. The study provides exemplars that explain lived experiences.

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

    SciTech Connect

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

    2013-03-21

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

  9. Designing Learning Experiences for Deeper Understanding

    ERIC Educational Resources Information Center

    Stripling, Barbara K.; Harada, Violet H.

    2012-01-01

    Planning is the less visible part of the teaching and learning process; however, it serves as the blueprint for student learning. To conceptualize the unit or project as a holistic learning experience, the authors created the C.L.E.A.R. G.O.A.L.S. guidelines that address the major elements of unit planning. An essential step is identifying the…

  10. Understanding Credit Risk: A Classroom Experiment

    ERIC Educational Resources Information Center

    Servatka, Maros; Theocharides, George

    2011-01-01

    This classroom experiment introduces students to the notion of credit risk and expected return, by allowing them to trade on comparable corporate bond issues from two types of markets: investment-grade and high-yield markets. Investment-grade issues have a lower probability of default than high-yield issues and thus provide a lower yield.…

  11. Understanding the College First-Year Experience

    ERIC Educational Resources Information Center

    Kidwell, Kirk S.

    2005-01-01

    Each fall, thousands of high school graduates launch into the next phase of their academic careers: college. They arrive on campuses across the United States full of hope and optimism, trepidation and anxiety. All intensely feel both the eagerness to excel and the fear of failure. The author shares his experience of dealing with college first-year…

  12. Effect of Two-Tier Diagnostic Tests on Promoting Learners' Conceptual Understanding of Variables in Conducting Scientific Experiments

    ERIC Educational Resources Information Center

    Çil, Emine

    2015-01-01

    Taking a test generally improves the retention of the material tested. This is a phenomenon commonly referred to as testing effect. The present research investigated whether two-tier diagnostic tests promoted student teachers' conceptual understanding of variables in conducting scientific experiments, which is a scientific process skill. In this…

  13. The impact of program experiences on the retention of women engineering students in Mexico

    NASA Astrophysics Data System (ADS)

    Villa, Maria Del Carmen Garcia

    This qualitative study sought to describe and understand the experiences of female students attending engineering colleges in Mexico and the sources of support and strategies that helped them persist in their programs. The participants were 20 women engineering students enrolled in at least their third year in selected colleges of engineering in Mexico, in both public and private universities, and pursuing a variety of engineering majors. Findings focus on the experiences of female students that helped them stay in their programs. Participants described their experiences in college as very challenging and perceived the environment as hostile and uncertain. In addition, patriarchal Mexican cultural values and stereotypes were identified by students as influencing and helping shape the engineering environment. However, in this context, participants were able to find sources of support and use strategies that helped them remain in their majors, such as a strong desire to succeed, a perceived academic self-ability; and support from their families, peers, institutions, and---most importantly---their professors. Furthermore, the fact that participants were able to persist in their programs gave them a sense of pride and satisfaction that was shared by their families, peers, and faculty. In addition, participants experienced contradictory forces and were constantly negotiating between rejecting traditional gender norms and upholding the norms that are so deeply engrained in Mexican society. Finally, as the students advanced in their programs and became "accepted to the club," they tended to reproduce the male-dominated value system present in engineering colleges accepting their professors' expectations of being "top students," accepting the elitist culture of engineering superiority, and embracing the protection given by their male peers. Retention of Mexican female engineering students is important for all engineering colleges, but cultural factors must be taken into

  14. Reactive transport modeling for Cs retention: from batch to field experiments

    NASA Astrophysics Data System (ADS)

    De Pourcq, K.; Ayora, C.; Carrera, J.; García-Gutiérrez, M.; Missana, T.; Mingarro, M.

    2012-04-01

    A Permeable Reactive Barrier has been designed to treat 137Cs polluted groundwater. In order to check both reactivity and permeability, laboratory batch and column tests combined with reactive transport modeling have been performed. The trapping mechanism is based on the sorption of cesium mainly on illite-containing clays. Batch experiments were conducted to obtain the partition coefficients (Kd) of different clay samples in solutions with different potassium concentration. A clear correlation of Kd values with potassium content was observed. The results were modeled with a cation-exchange model. The permeability of the reactive material is provided by the dispersion of the clay on a matrix of wooden shavings. Constant head tests allowed obtaining permeability values. Several column experiments with different flow rates were conducted to confirm the 137Cs retention under different conditions. A blind 1D reactive transport model based on the cation-exchange model was able to predict reasonably well the results of column experiments. The reactive transport model, validated with the column experiments, was used to investigate the performance and duration of 1m thick barrier under different scenarios (flow, clay proportion, 137Cs and K concentration). As expected, the sensitivity tests proved that the retention capacity of dissolved 137Cs in groundwater depends linearly on the amount of clay used in the filling material. As well, the operation time increases linearly when decreasing the flow rate. Finally, the concentration of potassium in inflow water has a remarkable and non-linear influence in the retention of 137Cs. Very high concentrations of potassium are the greatest threat and can lead to the unfeasibility of a permeable reactive barrier. Due to the Cs-K competition, the barrier is comparatively more efficient to treat high concentrations of 137Cs. Up to now, preliminary results from a field scale experiment have confirmed the reactivity and permeability

  15. Understanding HIV care delays in the US South and the role of the social-level in HIV care engagement/retention: a qualitative study

    PubMed Central

    2014-01-01

    Introduction In a significant geographical shift in the distribution of HIV infection, the US South - comprising 17 states - now has the greatest number of adults and adolescents with HIV (PLHIV) in the nation. More than 60% of PLHIV are not in HIV care in Alabama and Mississippi, contrasted with a national figure of 25%. Poorer HIV outcomes raise concerns about HIV-related inequities for southern PLHIV, which warrant further study. This qualitative study sought to understand experiences of low-income PLHIV on the AIDS Drug Assistance Program in engagement and retention in continuous HIV care in two sites in Alabama. Methods The study was designed using grounded theory. Semi-structured interviews with 25 PLHIV explored experiences with care linkage, reported factors and behaviors affecting engagement/retention in continuous HIV care, including socio-economic factors. To triangulate sources, 25 additional interviews were conducted with health and social service providers from the same clinics and AIDS Service Organizations where clients obtained services. Across the narratives, we used the HIV care continuum to map where care delays and drop out occurred. Using open coding, constant comparison and iterative data collection and analysis, we constructed a conceptual model illustrating how participants described their path to HIV care engagement and retention. Results Most respondents reported delayed HIV care, describing concentric factors: psychological distress, fear, lack of information, substance use, incarceration, lack of food, transport and housing. Stark health system drop out occurred immediately after receipt of HIV test results, with ART initiation generally occurring when individuals became ill. Findings highlight these enablers to care: Alabama's 'social infrastructure'; 'twinning' medical with social services, 'social enablers' who actively link PLHIV to care; and 'enabling spaces' that break down PLHIV isolation, facilitating HIV care linkage/retention

  16. Mesocosm experiments to assess factors affecting phosphorus retention and release in an extended Wisconsin wetland

    USGS Publications Warehouse

    Elder, J.F.; Manion, B.J.; Goddard, G.L.

    1997-01-01

    Phosphorus retention by wetland sediments and vegetation was investigated in Jackson Creek wetland, an extension of an existing prairie marsh in southeastern Wisconsin. The extended wetland construction was undertaken in 1992-93 to help reduce the phosphorus loading to a downstream eutrophic lake. Two approaches were used to study potential and actual phosphorus retention in the system. Mesocosm experiments of 20-40 days duration indicated that retention of total and dissolved reactive phosphorus in mesocosm cells containing macrophytes and/or sediments was reduced by factors of 2-20 relative to cells containing only water or a copper algicide to suppress metabolic activity. In contrast to the nutrient trapping function, these results show a potential for net phosphorus release that can be associated with increased biological richness. Measurements of water flow and nutrient loads at the wetland's inflow and outflow points demonstrated 9-39% net uptake of phosphorus on an annual scale but frequent occurrences of net phosphorus release over shorter (one-month) time scales. These episodes of release are most likely during the summer months. Thus, the wetland role in phosphorus cycling is not one of a true source or sink, although the annual budget data alone suggest substantial net retention. Effective management of the wetland for its nutrient trapping potential can be hindered by this oversimplification. The system is instead subject to relatively short-term alternation between net import and export. The periodic phosphorus export, although representing a small fraction of net annual import, could be critical for growth of macrophyte and algal communities downstream.

  17. Mathematics teachers' support and retention: using Maslow's hierarchy to understand teachers' needs

    NASA Astrophysics Data System (ADS)

    Fisher, Molly H.; Royster, David

    2016-10-01

    As part of a larger study, four mathematics teachers from diverse backgrounds and teaching situations report their ideas on teacher stress, mathematics teacher retention, and their feelings about the needs of mathematics teachers, as well as other information crucial to retaining quality teachers. The responses from the participants were used to develop a hierarchy of teachers' needs that resembles Maslow's hierarchy, which can be used to better support teachers in various stages of their careers. The interviews revealed both non content-specific and content-specific needs within the hierarchy. The responses show that teachers found different schools foster different stress levels and that as teachers they used a number of resources for reducing stress. Other mathematics-specific ideas are also discussed such as the amount of content and pedagogy courses required for certification.

  18. The effectiveness of using computer simulated experiments on junior high students' understanding of the volume displacement concept

    NASA Astrophysics Data System (ADS)

    Choi, Byung-Soon; Gennaro, Eugene

    Several researchers have suggested that the computer holds much promise as a tool for science teachers for use in their classrooms (Bork, 1979, Lunetta & Hofstein, 1981). It also has been said that there needs to be more research in determining the effectiveness of computer software (Tinker, 1983).This study compared the effectiveness of microcomputer simulated experiences with that of parallel instruction involving hands-on laboratory experiences for teaching the concept of volume displacement to junior high school students. This study also assessed the differential effect on students' understanding of the volume displacement concept using sex of the students as another independent variable. In addition, it compared the degree of retention, after 45 days, of both treatment groups.It was found that computer simulated experiences were as effective as hands-on laboratory experiences, and that males, having had hands-on laboratory experiences, performed better on the posttest than females having had the hands-on laboratory experiences. There were no significant differences in performance when comparing males with females using the computer simulation in the learning of the displacement concept. This study also showed that there were no significant differences in the retention levels when the retention scores of the computer simulation groups were compared to those that had the hands-on laboratory experiences. However, an ANOVA of the retention test scores revealed that males in both treatment conditions retained knowledge of volume displacement better than females.

  19. Children's Understandings of Rurality: Exploring the Interrelationship between Experience and Understanding.

    ERIC Educational Resources Information Center

    McCormack, Jaleh

    2002-01-01

    Explores children's material and discursive experiences of rurality in New Zealand and how they contribute to children's understandings of rurality. Highlights common constructions of reality based on experiences of agriculture, nature, and recreation, as well as children's understandings of rurality from discourse with peers and adults. (Contains…

  20. Taming theory with thought experiments: Understanding and scientific progress.

    PubMed

    Stuart, Michael T

    2016-08-01

    I claim that one way thought experiments contribute to scientific progress is by increasing scientific understanding. Understanding does not have a currently accepted characterization in the philosophical literature, but I argue that we already have ways to test for it. For instance, current pedagogical practice often requires that students demonstrate being in either or both of the following two states: 1) Having grasped the meaning of some relevant theory, concept, law or model, 2) Being able to apply that theory, concept, law or model fruitfully to new instances. Three thought experiments are presented which have been important historically in helping us pass these tests, and two others that cause us to fail. Then I use this operationalization of understanding to clarify the relationships between scientific thought experiments, the understanding they produce, and the progress they enable. I conclude that while no specific instance of understanding (thus conceived) is necessary for scientific progress, understanding in general is.

  1. Understanding recruitment and retention in the NHS community pharmacy stop smoking service: perceptions of smoking cessation advisers

    PubMed Central

    Sohanpal, Ratna; Rivas, Carol; Steed, Liz; MacNeill, Virginia; Kuan, Valerie; Edwards, Elizabeth; Griffiths, Chris; Eldridge, Sandra; Taylor, Stephanie; Walton, Robert

    2016-01-01

    Objectives To understand views of pharmacy advisers about smoker recruitment and retention in the National Health Service community pharmacy stop smoking programme. Design Thematic framework analysis of semistructured, in-depth interviews applying the Theoretical Domains Framework and COM-B behaviour change model. We aimed to identify aspects of adviser behaviour that might be modified to increase numbers joining and completing the programme. Participants 25 stop smoking advisers (13 pharmacists and 12 support staff). Setting 29 community pharmacies in 3 inner east London boroughs. Results Advisers had preconceived ideas about smokers likely to join or drop out and made judgements about smokers' readiness to quit. Actively recruiting smokers was accorded low priority due in part to perceived insufficient remuneration to the pharmacy and anticipated challenging interactions with smokers. Suggestions to improve smoker recruitment and retention included developing a more holistic and supportive approach using patient-centred communication. Training counter assistants were seen to be important as was flexibility to extend the programme duration to fit better with smokers’ needs. Conclusions Cessation advisers feel they lack the interpersonal skills necessary to engage well with smokers and help them to quit. Addressing advisers' behaviours about active engagement and follow-up of clients, together with regular skills training including staff not formally trained as cessation advisers, could potentially boost numbers recruited and retained in the stop smoking programme. Adjustments to the pharmacy remuneration structure to incentivise recruitment and to allow personalisation of the programme for individual smokers should also be considered. PMID:27388355

  2. Formation and retention of organically bound deuterium in rice in deuterium water release experiment.

    PubMed

    Atarashi-Andoh, Mariko; Amano, Hikaru; Kakiuchi, Hideki; Ichimasa, Michiko; Ichimasa, Yusuke

    2002-06-01

    As a substitute of tritium, deuterated water (D2O) vapor release experiments were performed in a greenhouse to estimate the different formation and subsequent retention of organically bound deuterium in rice plants between daytime and nighttime exposure. Potted rice plants were exposed to D2O vapor in the greenhouse for 8 h, under day or night conditions. Deuterium concentrations in free water and organic matter in rice leaves and ears were investigated until harvest time. The formation of organically bound deuterium in the daytime was higher than during the nighttime by the factors of 2.4 for the ear and 2.9 for the leaf. The decrease of the organically bound deuterium concentration in the ear after the nighttime exposure was faster than that after the daytime exposure. Data analysis was carried out using a compartment model in which different generating processes of organic matter were considered. The calculated organically bound deuterium retention in rice agreed with the measured value.

  3. Academic Career Selection and Retention in Radiation Oncology: The Joint Center for Radiation Therapy Experience

    SciTech Connect

    Balboni, Tracy A. . E-mail: tbalboni@partners.org; Chen, M.-H.; Harris, Jay R.; Recht, Abram; Stevenson, Mary Ann; D'Amico, Anthony V.

    2007-05-01

    Purpose: The United States healthcare system has witnessed declining reimbursement and increasing documentation requirements for longer than 10 years. These have decreased the time available to academic faculty for teaching and mentorship. The impact of these changes on the career choices of residents is unknown. The purpose of this report was to determine whether changes have occurred during the past decade in the proportion of radiation oncology trainees from a single institution entering and staying in academic medicine. Methods and Materials: We performed a review of the resident employment experience of Harvard Joint Center for Radiation Therapy residents graduating during 13 recent consecutive years (n = 48 residents). The outcomes analyzed were the initial selection of an academic vs. nonacademic career and career changes during the first 3 years after graduation. Results: Of the 48 residents, 65% pursued an academic career immediately after graduation, and 44% remained in academics at the last follow-up, after a median of 6 years. A later graduation year was associated with a decrease in the proportion of graduates immediately entering academic medicine (odds ratio, 0.78; 95% confidence interval, 0.65-0.94). However, the retention rate at 3 years of those who did immediately enter academics increased with a later graduation year (p = 0.03). Conclusion: During a period marked by notable changes in the academic healthcare environment, the proportion of graduating Harvard Joint Center for Radiation Therapy residents pursuing academic careers has been declining; however, despite this decline, the retention rates in academia have increased.

  4. Understanding the Role of Uncertainty in Jealousy Experience and Expression.

    ERIC Educational Resources Information Center

    Afifi, Walid A.; Reichert, Tom

    1996-01-01

    Confirms the value of uncertainty for understanding jealousy. Finds that subjects were more likely to experience and less likely to directly express jealousy at high, versus low, levels of relational state uncertainty. Highlights the importance of differentiating jealousy experience from expression, and corroborates recent evidence showing a…

  5. Improving pharmacy students' understanding and long-term retention of acid-base chemistry.

    PubMed

    Roche, Victoria F

    2007-12-15

    Despite repeated exposure to the principles underlying the behavior of organic acids and bases in aqueous solution, some pharmacy students remain confused about the topic of acid-base chemistry. Since a majority of organic drug molecules have acid-base character, the ability to predict their reactivity and the extent to which they will ionize in a given medium is paramount to students' understanding of essentially all aspects of drug action in vivo and in vitro. This manuscript presents a medicinal chemistry lesson in the fundamentals of acid-base chemistry that many pharmacy students have found enlightening and clarifying.

  6. Improving Pharmacy Students' Understanding and Long-term Retention of Acid-Base Chemistry

    PubMed Central

    2007-01-01

    Despite repeated exposure to the principles underlying the behavior of organic acids and bases in aqueous solution, some pharmacy students remain confused about the topic of acid-base chemistry. Since a majority of organic drug molecules have acid-base character, the ability to predict their reactivity and the extent to which they will ionize in a given medium is paramount to students' understanding of essentially all aspects of drug action in vivo and in vitro. This manuscript presents a medicinal chemistry lesson in the fundamentals of acid-base chemistry that many pharmacy students have found enlightening and clarifying PMID:19503706

  7. Analysis of the parameter identifiability of the in situ diffusion and retention (DR) experiments

    NASA Astrophysics Data System (ADS)

    Samper, Javier; Yi, Shuping; Naves, Acacia

    In situ diffusion experiments are performed at underground research laboratories to overcome the limitations of laboratory diffusion experiments. The diffusion and retention (DR) experiments are long-term, natural-scale, in situ experiments performed in the anisotropic Opalinus Clay Formation at Mont Terri, Switzerland. Dilution data are monitored at the injection interval and overcoring data will be measured at samples around the injection interval at the end of the experiment during overcoring. Interpretation of DR experiments is complicated by the non-ideal effects caused by the sintered filter, the gap between the filter and the borehole wall and the excavation disturbed zone (EdZ). Their impact on parameter estimates has been evaluated with numerical sensitivity analyses and synthetic experiments having the same geometry and parameters as the real DR experiments. Dimensionless sensitivities of tracer concentrations in the injection interval and along the overcoring profiles have been computed numerically. They have been used to identify the tracer parameters that can be estimated with the least uncertainty from tracer dilution and overcoring data. Sensitivities of tracer dilution data change with time and those of overcoring concentrations along the bedding are different from those along profiles normal to the bedding. Concentrations along overcoring profiles are sensitive to the effective diffusion normal to the bedding. Synthetic experiments generated with prescribed known parameters have been interpreted automatically with INVERSE-CORE 2D and used to evaluate the relevance of non-ideal effects and determine parameter identifiability in the presence of random errors for HTO and 22Na +. Model results show that it is difficult to estimate the parameters of the undisturbed clay when the tracer dilution data contain noise. The convergence of the estimation algorithm improves when the starting values are smaller than the true parameters. Although the parameters

  8. African American Students at Predominantly White Institutions: A Motivational and Self-Systems Approach to Understanding Retention

    ERIC Educational Resources Information Center

    Rodgers, Kelly A.; Summers, Jessica J.

    2008-01-01

    Predominantly White institutions have not been as effective as historically Black institutions in retaining and conferring degrees upon African American college students. This review seeks to embed the psychological aspects of the retention process proposed by Bean and Eaton ["A psychological model of college student retention." In J. M. Braxton…

  9. Toward a Greater Understanding of Hispanic Undergraduate Retention at a Private Christian University Using Narrative Inquiry and Autoethnographic Methods

    ERIC Educational Resources Information Center

    Sanchez, Robert

    2016-01-01

    Student retention is considered a complex human behavior. Adding to the complex nature of student retention is the ever changing landscape of higher education due in large part to the growth of Hispanic undergraduate student enrollment on college campuses. While notable gains have been made increasing the number of Hispanic students graduating…

  10. The Retention Puzzle Reconsidered: Second Year Student Attitudes and Experiences with Advising

    ERIC Educational Resources Information Center

    Walsh, Michael Edward

    2013-01-01

    College student retention has been described as a puzzle because retention rates have stagnated, and in some cases declined, despite over seventy years of research into the problem. The magnitude of the problem is that 50 percent of college students will leave their institution before obtaining a degree (Braxton, Hirschy, & McClendon, 2011).…

  11. The 2009 Kurt Hahn Address: Seeking Deeper Understandings from Experiences

    ERIC Educational Resources Information Center

    Knapp, Clifford E.

    2010-01-01

    This address used a narrative style to convey several stories drawn from the speaker's life. These stories illustrated various points about the value of experience for expanding learners' deep understandings of the content through the use of know-how knowledge. Know-how knowledge was contrasted with know-that knowledge in order to demonstrate the…

  12. Understandings, Definitions, and Experiences of Clergy in Residential Psychiatric Treatment.

    ERIC Educational Resources Information Center

    Brenneis, Michael J.

    2002-01-01

    Examines the understandings, definitions, and experiences of forgiveness held by members of the clergy who reported conflict with the religious superiors who mandated their entry into residential psychiatric treatment because of substance abuse/dependence, sexual misconduct, compulsive behavior disorder, or affective disorders. Compares the data…

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

    PubMed

    Gemme, E M

    1997-01-01

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

  14. User Evaluation of the Effects of a Text Simplification Algorithm Using Term Familiarity on Perception, Understanding, Learning, and Information Retention

    PubMed Central

    2013-01-01

    , 7 multiple-choice questions without the text for learning, and 2 free recall questions for information retention. Results Ninety-nine participants completed the study. We found strong beneficial effects on both perceived and actual difficulty. After simplification, the text was perceived as simpler (P<.001) with simplified text scoring 2.3 and original text 3.2 on the 5-point Likert scale (score 1: easiest). It also led to better understanding of the text (P<.001) with 11% more correct answers with simplified text (63% correct) compared to the original (52% correct). There was more learning with 18% more correct answers after reading simplified text compared to 9% more correct answers after reading the original text (P=.003). There was no significant effect on free recall. Conclusions Term familiarity is a valuable feature in simplifying text. Although the topic of the text influences the effect size, the results were convincing and consistent. PMID:23903235

  15. Distributed Revisiting: An Analytic for Retention of Coherent Science Learning

    ERIC Educational Resources Information Center

    Svihla, Vanessa; Wester, Michael J.; Linn, Marcia C.

    2015-01-01

    Designing learning experiences that support the development of coherent understanding of complex scientific phenomena is challenging. We sought to identify analytics that can also guide such designs to support retention of coherent understanding. Based on prior research that distributing study of material over time supports retention, we explored…

  16. Defining retention and attrition in pre-antiretroviral HIV care: proposals based on experience in Africa

    PubMed Central

    Fox, Matthew P; Larson, Bruce; Rosen, Sydney

    2013-01-01

    Objective To propose practical, standardized definitions for reporting retention for pre-ART care. Method Definitions footed on three stages: Stage 1, testing HIV-positive to initial ART eligibility assessment; Stage 2, initial assessment to ART eligibility; and Stage 3, ART eligibility to ART initiation. For each stage, negative outcomes include death, loss, or not being retained. Results Stage 1 Retention: proportion of patients who complete initial ART eligibility assessment within 3 months of HIV testing, with reporting of cohort outcomes at 3 and 12 months after HIV testing. Patients who end Stage 1 eligible for ART move directly to Stage 3. Stage 2 Retention: proportion of patients who either: complete all possible ART eligibility re-assessments within 6 months of the site’s standard visit schedule; or had an assessment within 1 year of the time reported to and were not ART eligible at the last assessment. Retention should be reported at 12-month intervals. Stage 3 Retention: initiating ART (i.e. ARVs dispensed) within 3 months of determining ART eligibility, with reporting at 3 months after eligibility and 3 monthly intervals thereafter. Conclusion If pre-ART retention is to improve, consistent terminology is needed for collecting data, measuring and reporting outcomes, and comparing results across programs and countries. The definitions we propose offer a strategy for improving the consistency and comparability of future reports. PMID:22863075

  17. Understanding the Behavioral Determinants of Retention in HIV Care: A Qualitative Evaluation of a Situated Information, Motivation, Behavioral Skills Model of Care Initiation and Maintenance

    PubMed Central

    Fisher, Jeffrey D.; Cunningham, Chinazo O.; Amico, K. Rivet

    2012-01-01

    Abstract The current study provides a qualitative test of a recently proposed application of an Information, Motivation, Behavioral Skills (IMB) model of health behavior situated to the social-environmental, structural, cognitive-affective, and behavioral demands of retention in HIV care. Mixed-methods qualitative analysis was used to identify the content and context of critical theory-based determinants of retention in HIV care, and to evaluate the relative fit of the model to the qualitative data collected via in-depth semi-structured interviews with a sample of inner-city patients accessing traditional and nontraditional HIV care services in the Bronx, NY. The sample reflected a diverse marginalized patient population who commonly experienced comorbid chronic conditions (e.g., psychiatric disorders, substance abuse disorders, diabetes, hepatitis C). Through deductive content coding, situated IMB model-based content was identified in all but 7.1% of statements discussing facilitators or barriers to retention in HIV care. Inductive emergent theme identification yielded a number of important themes influencing retention in HIV care (e.g., acceptance of diagnosis, stigma, HIV cognitive/physical impairments, and global constructs of self-care). Multiple elements of these themes strongly aligned with the model's IMB constructs. The convergence of the results from both sets of analysis demonstrate that participants' experiences map well onto the content and structure of the situated IMB model, providing a systematic classification of important theoretical and contextual determinants of retention in care. Future intervention efforts to enhance retention in HIV care should address these multiple determinants (i.e., information, motivation, behavioral skills) of self-directed retention in HIV care. PMID:22612447

  18. Understanding dignity: experiences of impairment in an exercise facility.

    PubMed

    Johnston, Keith R; Goodwin, Donna L; Leo, Jennifer

    2015-04-01

    Dignity, as an essential quality of being human, has been overlooked in exercise contexts. The aim of this interpretative phenomenological study was to understand the meaning of dignity and its importance to exercise participation. The experiences of 21 adults (11 women and 10 men) from 19 to 65 yr of age who experience disability, who attended a specialized community exercise facility, were gathered using the methods of focus-group and one-on-one interviews, visual images, and field notes. The thematic analysis revealed 4 themes: the comfort of feeling welcome, perceptions of otherness, negotiating public spaces, and lost autonomy. Dignity was subjectively understood and nurtured through the respect of others. Indignities occurred when enacted social and cultural norms brought dignity to consciousness through humiliation or removal of autonomy. The specialized exercise environment promoted self-worth and positive self-beliefs through shared life experiences and a norm of respect.

  19. The Influence of Principal Gender, Teachers' Years of Experience, and Retention on Teacher Perceptions of Principal Leadership Style, Qualities, and Job Satisfaction

    ERIC Educational Resources Information Center

    Eddins, Gregg M.

    2012-01-01

    One main challenge for many school districts in these tough economic times is teacher retention and all the costs associated. This study looks the influence of principal gender, teacher years of experience, and teacher retention based on teachers' perceptions of their principal's leadership style, transformational leadership qualities,…

  20. Understanding the 'four directions of travel': qualitative research into the factors affecting recruitment and retention of doctors in rural Vietnam

    PubMed Central

    2011-01-01

    Background Motivation and retention of health workers, particularly in rural areas, is a question of considerable interest to policy-makers internationally. Many countries, including Vietnam, are debating the right mix of interventions to motivate doctors in particular to work in remote areas. The objective of this study was to understand the dynamics of the health labour market in Vietnam, and what might encourage doctors to accept posts and remain in-post in rural areas. Methods This study forms part of a labour market survey which was conducted in Vietnam in November 2009 to February 2010. The study had three stages. This article describes the findings of the first stage - the qualitative research and literature review, which fed into the design of a structured survey (second stage) and contingent valuation (third stage). For the qualitative research, three tools were used - key informant interviews at national and provincial level (6 respondents); in-depth interviews of doctors at district and commune levels (11 respondents); and focus group discussions with medical students (15 participants). Results The study reports on the perception of the problem by national level stakeholders; the motivation for joining the profession by doctors; their views on the different factors affecting their willingness to work in rural areas (including different income streams, working conditions, workload, equipment, support and supervision, relationships with colleagues, career development, training, and living conditions). It presents findings on their overall satisfaction, their ranking of different attributes, and willingness to accept different kinds of work. Finally, it discusses recent and possible policy interventions to address the distribution problem. Conclusions Four typical 'directions of travel' are identified for Vietnamese doctors - from lower to higher levels of the system, from rural to urban areas, from preventive to curative health and from public to private

  1. The Use of Grounded Theory to Develop a Framework for Understanding Student Retention in Community College Nursing Programs

    ERIC Educational Resources Information Center

    Priode, Kimberly S.

    2013-01-01

    Gaining admission into pre-licensure nursing programs has proven to be quite difficult for the average college student. Topping the list of crucial priorities for many academic institutions is the retention of these nursing students. Yet, the reality is that many students decide not to complete their course of study for reasons other than academic…

  2. Using a Complexity-Based Perspective to Better Understand the Relationships among Mentoring, School Conflicts, and Novice Retention

    ERIC Educational Resources Information Center

    Waterman, Sheryn Elaine Spencer

    2011-01-01

    In this study I used complexity-thinking, ecologically-based sustainable capacity-building, narrative methodology, and pragmatism to explore the relationships among mentoring, conflict, and novice retention. In order to explore these relationships, I constructed stories from my interviews with six mentor-novice dyads in a southeastern 9-12 high…

  3. Black Male Retention Initiatives: Exploring Students' Experiences and Program Effectiveness at Predominantly White Institutions

    ERIC Educational Resources Information Center

    St. Leger, Gabrielle

    2012-01-01

    Recent initiatives in higher education have been designed to increase Black undergraduate male collegiate retention and persistence through graduation for this historically underrepresented population. Although institutional leaders in higher education have focused on creating more inclusive campuses, designing and implementing programs to retain…

  4. Psychological Sense of Community and Retention: Rethinking the First-Year Experience of Students in STEM

    ERIC Educational Resources Information Center

    Dagley Falls, Melissa

    2009-01-01

    This investigation looks at the relationship between a STEM learning community's co-curricular activities and students' perceived sense of community (SOC) to determine which activities most influence SOC and, in turn, retention. This investigation shows that SOC can be impacted by a multitude of factors found within the college environment. The…

  5. The Role of Work Experience and Self-Efficacy in STEM Student Retention

    ERIC Educational Resources Information Center

    Raelin, Joseph A.; Bailey, Margaret B.; Hamann, Jerry; Pendleton, Leslie K.; Reisberg, Rachelle; Whitman, David L.

    2015-01-01

    The authors report the results of a three-year longitudinal study of retention among undergraduate engineering students enrolled at four major universities. The study demonstrates that self-efficacy can be a critical factor in student persistence and can be broken down into three components: work, career, and academic self-efficacy. The authors…

  6. The retention characteristics of nonvolatile SNOS memory transistors in a radiation environment: Experiment and model

    SciTech Connect

    McWhorter, P.J.; Miller, S.L.; Dellin, T.A.; Axness, C.L.

    1987-01-01

    Experimental data and a model to accurately and quantitatively predict the data are presented for retention of SNOS memory devices over a wide range of dose rates. A wide range of SNOS stack geometries are examined. The model is designed to aid in screening nonvolatile memories for use in a radiation environment.

  7. Creating meaningful learning experiences: Understanding students' perspectives of engineering design

    NASA Astrophysics Data System (ADS)

    Aleong, Richard James Chung Mun

    , relevance, and transfer. With this framework of student learning, engineering educators can enhance learning experiences by engaging all three levels of students' understanding. The curriculum studies orientation applied the three holistic elements of curriculum---subject matter, society, and the individual---to conceptualize design considerations for engineering curriculum and teaching practice. This research supports the characterization of students' learning experiences to help educators and students optimize their teaching and learning of design education.

  8. Critical contribution of nonlinear chromatography to the understanding of retention mechanism in reversed-phase liquid chromatography

    SciTech Connect

    Gritti, Fabrice; Guiochon, Georges A

    2005-11-01

    The retention of most compounds in RPLC proceeds through a combination of several independent mechanisms. We review a series of recent studies made on the behavior of several commercial C{sub 18}-bonded stationary phases and of the complex, mixed retention mechanisms that were observed in RPLC. These studies are essentially based on the acquisition of adsorption isotherm data, on the modeling, and on the interpretation of these data. Because linear chromatography deals only with the initial slope of the global, overall, or apparent isotherm, it is unable fully to describe the complete adsorption mechanism. It cannot even afford clues as to the existence of several overlaid retention mechanisms. More specifically, it cannot account for the consequences of the surface heterogeneity of the packing material. The acquisition of equilibrium data in a wide concentration range is required for this purpose. Frontal analysis (FA) of selected probes gives data that can be modeled into equilibrium isotherms of these probes and that can also be used to calculate their adsorption or affinity energy distribution (AED). The combination of these data, the detailed study of the best constants of the isotherm model, the determination of the influence of experimental parameters (e.g., buffer pH and pI, temperature) on the isotherm constants provide important clues regarding the heterogeneity of the adsorbent surface and the main properties of the adsorption mechanisms. The comparison of similar data obtained for the adsorption of neutral and ionizable compounds, treated with the same approach, and the investigation of the influence on the thermodynamics of phase equilibrium of the experimental conditions (temperature, average pressure, mobile phase composition, nature of the organic modifier, and, for ionizable compounds, of the ionic strength, the nature, the concentration of the buffer, and its pH) brings further information. This review provides original conclusions regarding

  9. Understanding the learning assistant experience with physics identity

    NASA Astrophysics Data System (ADS)

    Close, Eleanor W.; Close, Hunter G.; Donnelly, David

    2013-01-01

    Learning Assistants (LAs) have been shown to have better conceptual understanding and more favorable beliefs about science than non-LAs, and are more likely to choose a career in K-12 science teaching [1]. We propose that connections between elements of identity, persistence, and participation in an LA program can be explained using the concept of the community of practice and its intimate relationship to identity [2]. In separate work, Hazari et al. found that physics identity was highly correlated to expressed career plans in physics [3]. We hypothesize that a thriving LA program has many features of a well-functioning community of practice and contributes to all four elements of physics identity: personal interest, student performance, competence, and recognition by others. We explore how this analysis of the LA experience might shape decisions and influence outcomes of adoption and adaptations of the LA model.

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  11. Cootie Genetics: Simulating Mendel's Experiments to Understand the Laws of Inheritance

    ERIC Educational Resources Information Center

    Galloway, Katelyn; Anderson, Nadja

    2014-01-01

    "Cootie Genetics" is a hands-on, inquiry-based activity that enables students to learn the Mendelian laws of inheritance and gain an understanding of genetics principles and terminology. The activity begins with two true-breeding Cooties of the same species that exhibit five observable trait differences. Students observe the retention or…

  12. Examining Workplace Ostracism Experiences in Academia: Understanding How Differences in the Faculty Ranks Influence Inclusive Climates on Campus.

    PubMed

    Zimmerman, Carla A; Carter-Sowell, Adrienne R; Xu, Xiaohong

    2016-01-01

    Research on the retention of women in academia has focused on challenges, including a "chilly climate," devaluation, and incivility. The unique consequences of workplace ostracism - being ignored and excluded by others in an organizational setting - require focus on this experience as another interpersonal challenge for women in academia. The purpose of this study is to examine differences in the faculty experiences and outcomes of workplace ostracism, and to determine if these experiences are affected significantly by the gender composition of an employee's specific department. Participants were recruited at two time points to complete campus climate surveys that were distributed to faculty at a large, public, research university. We examined the number of reported ostracism experiences (Study 1) and perceived information sharing (Study 2) among male and female university faculty. The findings indicated that female faculty members perceived more workplace ostracism than male faculty members. Analyses of department gender ratios suggested that the proportion of women in the department did not reduce the amount of workplace ostracism experienced by women. No gender differences were found in perceived information sharing. However, we found that Faculty of Color, both men and women, reported more frequent information exclusion than White faculty. These results have important implications for theoretical and practical understandings of workplace demography and suggest that it is necessary to look at subtle, ambiguous forms of discrimination in order to increase retention of faculty from underrepresented groups in academia.

  13. Examining Workplace Ostracism Experiences in Academia: Understanding How Differences in the Faculty Ranks Influence Inclusive Climates on Campus

    PubMed Central

    Zimmerman, Carla A.; Carter-Sowell, Adrienne R.; Xu, Xiaohong

    2016-01-01

    Research on the retention of women in academia has focused on challenges, including a “chilly climate,” devaluation, and incivility. The unique consequences of workplace ostracism – being ignored and excluded by others in an organizational setting – require focus on this experience as another interpersonal challenge for women in academia. The purpose of this study is to examine differences in the faculty experiences and outcomes of workplace ostracism, and to determine if these experiences are affected significantly by the gender composition of an employee’s specific department. Participants were recruited at two time points to complete campus climate surveys that were distributed to faculty at a large, public, research university. We examined the number of reported ostracism experiences (Study 1) and perceived information sharing (Study 2) among male and female university faculty. The findings indicated that female faculty members perceived more workplace ostracism than male faculty members. Analyses of department gender ratios suggested that the proportion of women in the department did not reduce the amount of workplace ostracism experienced by women. No gender differences were found in perceived information sharing. However, we found that Faculty of Color, both men and women, reported more frequent information exclusion than White faculty. These results have important implications for theoretical and practical understandings of workplace demography and suggest that it is necessary to look at subtle, ambiguous forms of discrimination in order to increase retention of faculty from underrepresented groups in academia. PMID:27303322

  14. Experiment studies of iodinated oil nanometer ferrofluid retention in rabbit liver.

    PubMed

    Zhang, X; Lin, R; Lin, Y; Wu, R H

    2005-01-01

    To study possibility for iodinated oil nanometer ferrofluid retention in rabbit liver. 131I- iodinated oil nanometer ferrofluid were injected into liver right lobe through portal vein in 5 rabbits... - calibrate meter showed continuous.. counts in the region injected. Then the relative metabolic parameters were calculated. Left lobe livers, right lobe livers and lungs of the rabbits were examined in pathology, and the right lobe livers were examined by electron microscope. Five rabbits injected purely 131Iiodinated oil were designated as control group. Single metabolic mode was found in the rabbits in nanometer ferrofluid group. The biological half-life of 131I- iodinated oil nanometer ferrofluid was not different from control group's slow metabolic portion. But control group's rapid metabolic portion were eliminated in a higher speed, range from 8% to 44%. More damage was found in nanometer ferrofluid group's right lobe livers. 131I- iodinated oil nanometer ferrofluid possess the opportunity of local retention in human body and further study is worthwhile.

  15. Understanding interference experiments with polarized light through photon trajectories

    SciTech Connect

    Sanz, A.S. Davidovic, M.; Bozic, M.; Miret-Artes, S.

    2010-04-15

    Bohmian mechanics allows to visualize and understand the quantum-mechanical behavior of massive particles in terms of trajectories. As shown by Bialynicki-Birula, Electromagnetism also admits a hydrodynamical formulation when the existence of a wave function for photons (properly defined) is assumed. This formulation thus provides an alternative interpretation of optical phenomena in terms of photon trajectories, whose flow yields a pictorial view of the evolution of the electromagnetic energy density in configuration space. This trajectory-based theoretical framework is considered here to study and analyze the outcome from Young-type diffraction experiments within the context of the Arago-Fresnel laws. More specifically, photon trajectories in the region behind the two slits are obtained in the case where the slits are illuminated by a polarized monochromatic plane wave. Expressions to determine electromagnetic energy flow lines and photon trajectories within this scenario are provided, as well as a procedure to compute them in the particular case of gratings totally transparent inside the slits and completely absorbing outside them. As is shown, the electromagnetic energy flow lines obtained allow to monitor at each point of space the behavior of the electromagnetic energy flow and, therefore, to evaluate the effects caused on it by the presence (right behind each slit) of polarizers with the same or different polarization axes. This leads to a trajectory-based picture of the Arago-Fresnel laws for the interference of polarized light.

  16. Student and Teacher Experiences of Assessing Different Levels of Understanding

    ERIC Educational Resources Information Center

    Lundberg, Angela

    2004-01-01

    Examinations greatly influence course structures and student study strategies. A course for students in the civil and environmental engineering programme at Lulea University of Technology was reconstructed with the aim of increasing levels of understanding. A simple written test was designed to assess low levels of understanding (definitions,…

  17. The Effects of Primary Sources and Field Trip Experience on the Knowledge Retention of Multicultural Content

    ERIC Educational Resources Information Center

    Farmer, James; Knapp, Doug; Benton, Gregory M.

    2007-01-01

    Although small in scope, this study attempted to analyze the impacts of primary sources and field trip experiences on multicultural education through first-hand narrative interviews, one year after the experience. In particular, it assessed the recollections of students who participated in a one-half-day field trip to George Washington Carver…

  18. Student Experience Assessments: Best Practices in Student Satisfaction and Retention Research

    ERIC Educational Resources Information Center

    Scholder, Tara E.; Maguire, Linda Cox

    2009-01-01

    As students are asked to share more of the costs of a post-secondary education, the quality of their overall educational experience and perceived return on investment (ROI) are increasingly important. For prospective students and their parents, what they are told they can expect from the student experience at an institution often makes the most…

  19. Modeling Volatile Species Retention Experiments: Interim Progress Report (M3FT-12LA0202053)

    SciTech Connect

    Carlson, Neil N.

    2012-07-06

    Metal nuclear fuel is a candidate transmutation fuel form for advanced fuel cycles. One constituent of the fuel, americium, has a high vapor pressure, and there is a concern that excessive volatility losses of americium will occur during casting of the metal. A number of experiments have been performed using americium and surrogate metals, including experiments slated for FY12, to address the concern. The present task is to model and numerically simulate these experiments. This report describes a system-level model of the relevant experiments that has been developed together with some results. It also describes some initial 3D, full-physics simulations of portions of the experiments that have been performed.

  20. Metal retention on pine bark and blast furnace slag--on-site experiment for treatment of low strength landfill leachate.

    PubMed

    Nehrenheim, Emma; Waara, Sylvia; Johansson Westholm, Lena

    2008-03-01

    Treatment of landfill leachate using blast furnace slag and pine bark as reactive sorbents was studied in an in situ column experiment at the Lilla Nyby landfill site in Eskilstuna, Sweden. The columns were filled with approximately 101 of each sorbent and leachate was supplied at three different flow rates during a period of 4 months. Samples of inflow and outflow were collected three times a week and were analyzed for physical and chemical parameters, including concentrations of some metals, and toxicity. It was found that pine bark removed metals more efficiently than did the blast furnace slags; that Zn was most efficiently retained in the filters and that both retention time and initial concentration played an important role in the sorption process. It was also observed that the pine bark column did not release COD. No toxicity of the untreated or the treated leachate was found with the test organisms and test responses used.

  1. The Landscape of Vocational Progression in Higher Education: Understanding the Retention and Progression of Vocational Learners through a Regional Perspective

    ERIC Educational Resources Information Center

    Round, David; Brownless, Chris; Rout, Amelia

    2012-01-01

    This project aimed to better understand vocational student progression into higher education. Following an initial literature review a large dataset was purchased from the Higher Education Statistics Agency (covering the years 2002/3 to 2006/7 and 2007/8). This allowed for a quantitative analysis to take place which compared and contrasted the…

  2. An Experiment of Student Understanding of Accruals versus Cash Flows

    ERIC Educational Resources Information Center

    Miranda-Lopez, Jose Eduardo; Nichols, Linda M.

    2007-01-01

    The concepts of both accrual accounting and cash basis accounting need to be thoroughly understood by accounting graduates as they enter the workplace. In making decisions, both managers and investors often may need to make adjustments from one basis to the other. But do students really understand these concepts? This study uses an experimental…

  3. Fostering Intercultural Understanding through Secondary School Experiences of Cultural Immersion

    ERIC Educational Resources Information Center

    Walton, Jessica; Paradies, Yin; Priest, Naomi; Wertheim, Eleanor H.; Freeman, Elizabeth

    2015-01-01

    In parallel with many nations' education policies, national education policies in Australia seek to foster students' intercultural understanding. Due to Australia's location in the Asia-Pacific region, the Australian government has focused on students becoming "Asia literate" to support Australia's economic and cultural engagement with…

  4. Understanding Students' Experiences of Professionalism Learning: A "Threshold" Approach

    ERIC Educational Resources Information Center

    Neve, Hilary; Lloyd, Helen; Collett, Tracey

    2017-01-01

    Professionalism is a core element of curricula in many disciplines but can be difficult to teach and learn. This study used audio-diary methodology to identify professionalism threshold concepts in a small group learning setting in undergraduate medicine and to understand factors that might facilitate students to "get" such concepts.…

  5. Phosphorus retention and fractionation in an eutrophic wetland: A one-year mesocosms experiment under fluctuating flooding conditions.

    PubMed

    Tercero, María Del Carmen; Álvarez-Rogel, José; Conesa, Héctor Miguel; Párraga-Aguado, Isabel; González-Alcaraz, María Nazaret

    2017-04-01

    This study aimed to evaluate the response of salt marshes to pulses of PO4(3-)-enriched water, with and without the presence of Phragmites australis. A one-year mesocosms experiment was performed in simulated soil profiles (fine-textured surface layers and sandy subsurface layers) from a coastal salt marsh of the Mar Menor lagoon under alternating flooding-drying conditions with eutrophic water, under low (1.95 mg L(-1) P-PO4(3-)) and high (19.5 mg L(-1) P-PO4(3-)) P load, and with the presence/absence of Phragmites. The PO4(3-) concentrations in soil porewater and drainage water were regularly measured, and P accumulated in soils (including a fractionation procedure) and plants (roots, rhizomes, stems and leaves) were analyzed. The experimental mesocosms were highly effective in the removal of P from the eutrophic flooding water (>90% reduction of the P added to the system both in the soil pore water and drainage water), regardless of the nutrient load, the season of the year and the presence/absence of Phragmites. The soil was the main sink of the P added to the system, while Phragmites had a minor role in P removal. The biomass of Phragmites accumulated ∼27% of the P added with the flooding water in the treatment with water of low P load while ∼12% of P in that of high P load; the rhizomes were the organs that contributed the most (∼67-72% of the total P retained by the plants). Ca/Mg compounds were the main contributors to the retention of P in the soil compartment, especially in the fine-textured surface soil layers (∼34-53% of the total P in the soil was present in this fraction). Phragmites favored the retention of P onto metal oxides (∼12% increase of the P retained in the metal oxides fraction in the treatment with water of high P load). Hence, the use of constructed wetlands to ameliorate the negative impacts of P-enriched waters in the Mar Menor lagoon and similar areas is recommended. We propose the incorporation of fine

  6. Higher Education Teachers' Experiences with Learning Analytics in Relation to Student Retention

    ERIC Educational Resources Information Center

    West, Deborah; Huijser, Henk; Heath, David; Lizzio, Alf; Toohey, Danny; Miles, Carol; Searle, Bill; Bronnimann, Jurg

    2016-01-01

    This paper presents findings from a study of Australian and New Zealand academics (n = 276) that teach tertiary education students. The study aimed to explore participants' early experiences of learning analytics in a higher education milieu in which data analytics is gaining increasing prominence. Broadly speaking participants were asked about:…

  7. Great Expectations: Examining the Discrepancy between Expectations and Experiences on College Student Retention

    ERIC Educational Resources Information Center

    Pleitz, Jacob D.; MacDougall, Alexandra E.; Terry, Robert A.; Buckley, M. Ronald; Campbell, Nicole J.

    2015-01-01

    The purpose of this article is to build upon previous efforts evaluating the degree to which the discrepancy between student expectations and experiences can result in greater rates of attrition in education. Data were collected from 225 students at a large Midwestern public university and analyzed to assess the discrepancy between expectations…

  8. A Simple Calorimetric Experiment that Highlights Aspects of Global Heat Retention and Global Warming

    ERIC Educational Resources Information Center

    Burley, Joel D.; Johnston, Harold S.

    2007-01-01

    In this laboratory experiment, general chemistry students measure the heating curves for three different systems: (i) 500 g of room-temperature water heated by a small desk lamp, (ii) 500 g of an ice-water mixture warmed by conduction with room-temperature surroundings, and (iii) 500 g of an ice-water mixture heated by a small desk lamp and by…

  9. Course Management Systems in Higher Education: Understanding Student Experiences

    ERIC Educational Resources Information Center

    Yuen, Allan; Fox, Robert; Sun, Angie; Deng, Liping

    2009-01-01

    Purpose: The course management system (CMS), as an evolving tool and innovation, is increasingly used to promote the quality, efficiency and flexibility of teaching and learning in higher education. This paper aims to examine students' experiences of CMSs across faculties at a comprehensive university in Hong Kong. Design/methodology/approach:…

  10. A Dual-Identity Framework for Understanding Lesbian Experience

    ERIC Educational Resources Information Center

    Fingerhut, Adam W.; Peplau, Letitia Anne; Ghavami, Negin

    2005-01-01

    The diverse life experiences of contemporary lesbians are shaped by women's differing ties to two social worlds, the majority heterosexual society and the minority subculture of the lesbian or sexual-minority world. This article presents a detailed conceptual analysis of a dual-identity framework that emphasizes lesbians' simultaneous affiliations…

  11. Towards an Understanding of Muslim American Adolescent High School Experiences

    ERIC Educational Resources Information Center

    Seward, Derek X.; Khan, Shaza

    2016-01-01

    The researchers conducted a grounded theory study to explore the experiences of Muslim American adolescents in high school. Findings indicate that students had to navigate unique challenges because of their religious faith, but those obstacles presented opportunities to confront bias and discrimination. Recommendations for how school counselors…

  12. Understanding Students' Experiences of Well-Being in Learning Environments

    ERIC Educational Resources Information Center

    Stanton, Alisa; Zandvliet, David; Dhaliwal, Rosie; Black, Tara

    2016-01-01

    With the recent release of a new international charter on health promoting universities and institutions of higher education, universities and colleges are increasingly interested in providing learning experiences that enhance and support student well-being. Despite the recognition of learning environments as a potential setting for creating and…

  13. Understanding Student Attitudes toward Bible Reading: A Philippine Experience

    ERIC Educational Resources Information Center

    Baring, Rito V.

    2008-01-01

    Reflecting from the Philippine experience, this article explores an emerging picture that characterizes contemporary Bible reading attitudes of college students. Six new attitude factor definitions are developed following the development of the Bible Reading (BR) attitude scale for college students constructed by this author in a separate study.…

  14. Understanding Students' Experiences of Statistics in a Service Course

    ERIC Educational Resources Information Center

    Gordon, Sue

    2004-01-01

    In this paper we explore issues surrounding university students' experiences of statistics drawing on data related to learning statistics as a compulsory component of psychology. Over 250 students completed a written survey which included questions on their attitudes to learning statistics and their conceptions of statistics. Results indicated…

  15. Potential Water Retention Capacity as a Factor in Silage Effluent Control: Experiments with High Moisture By-product Feedstuffs

    PubMed Central

    Razak, Okine Abdul; Masaaki, Hanada; Yimamu, Aibibula; Meiji, Okamoto

    2012-01-01

    The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, ‘potential water retention capacity’ (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer’s grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (±10.3). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship. PMID:25049587

  16. Potential Water Retention Capacity as a Factor in Silage Effluent Control: Experiments with High Moisture By-product Feedstuffs.

    PubMed

    Razak, Okine Abdul; Masaaki, Hanada; Yimamu, Aibibula; Meiji, Okamoto

    2012-04-01

    The role of moisture absorptive capacity of pre-silage material and its relationship with silage effluent in high moisture by-product feedstuffs (HMBF) is assessed. The term water retention capacity which is sometimes used in explaining the rate of effluent control in ensilage may be inadequate, since it accounts exclusively for the capacity of an absorbent incorporated into a pre-silage material prior to ensiling, without consideration to how much the pre-silage material can release. A new terminology, 'potential water retention capacity' (PWRC), which attempts to address this shortcoming, is proposed. Data were pooled from a series of experiments conducted separately over a period of five years using laboratory silos with four categories of agro by-products (n = 27) with differing moisture contents (highest 96.9%, lowest 78.1% in fresh matter, respectively), and their silages (n = 81). These were from a vegetable source (Daikon, Raphanus sativus), a root tuber source (potato pulp), a fruit source (apple pomace) and a cereal source (brewer's grain), respectively. The pre-silage materials were adjusted with dry in-silo absorbents consisting wheat straw, wheat or rice bran, beet pulp and bean stalks. The pooled mean for the moisture contents of all pre-silage materials was 78.3% (±10.3). Silage effluent decreased (p<0.01), with increase in PWRC of pre-silage material. The theoretical moisture content and PWRC of pre-silage material necessary to stem effluent flow completely in HMBF silage was 69.1% and 82.9 g/100 g in fresh matter, respectively. The high correlation (r = 0.76) between PWRC of ensiled material and silage effluent indicated that the latter is an important factor in silage-effluent relationship.

  17. Lidar Uncertainty Measurement Experiment (LUMEX) - Understanding Sampling Errors

    NASA Astrophysics Data System (ADS)

    Choukulkar, A.; Brewer, W. A.; Banta, R. M.; Hardesty, M.; Pichugina, Y.; Senff, Christoph; Sandberg, S.; Weickmann, A.; Carroll, B.; Delgado, R.; Muschinski, A.

    2016-06-01

    Coherent Doppler LIDAR (Light Detection and Ranging) has been widely used to provide measurements of several boundary layer parameters such as profiles of wind speed, wind direction, vertical velocity statistics, mixing layer heights and turbulent kinetic energy (TKE). An important aspect of providing this wide range of meteorological data is to properly characterize the uncertainty associated with these measurements. With the above intent in mind, the Lidar Uncertainty Measurement Experiment (LUMEX) was conducted at Erie, Colorado during the period June 23rd to July 13th, 2014. The major goals of this experiment were the following: Characterize sampling error for vertical velocity statistics Analyze sensitivities of different Doppler lidar systems Compare various single and dual Doppler retrieval techniques Characterize error of spatial representativeness for separation distances up to 3 km Validate turbulence analysis techniques and retrievals from Doppler lidars This experiment brought together 5 Doppler lidars, both commercial and research grade, for a period of three weeks for a comprehensive intercomparison study. The Doppler lidars were deployed at the Boulder Atmospheric Observatory (BAO) site in Erie, site of a 300 m meteorological tower. This tower was instrumented with six sonic anemometers at levels from 50 m to 300 m with 50 m vertical spacing. A brief overview of the experiment outline and deployment will be presented. Results from the sampling error analysis and its implications on scanning strategy will be discussed.

  18. Headwater thermal response to partial-retention forest harvesting: a process-based paired-catchment experiment

    NASA Astrophysics Data System (ADS)

    Moore, R. D.; Guenther, S. M.; Gomi, T.

    2008-12-01

    Paired-catchment experiments are the most rigorous empirical research design for estimating the effects of land use on aquatic systems. However, they have recently come under increasing criticism, in part because past studies typically treated catchments as black boxes. As a result, investigators could only speculate about the factors responsible for any observed effects, limiting their ability to generalize the experimental results in space and time. This study used a paired-catchment approach to investigate the effects of partial- retention forest harvesting with no riparian buffer on the thermal regime of a headwater stream in coastal British Columbia. In addition to monitoring stream temperature at three locations within the treatment reach, we monitored above-stream microclimate, water surface evaporation, bed temperature profiles, groundwater temperature, and reach-scale surface-subsurface interaction. Daily maximum stream temperatures increased after harvesting by over 5 °C during summer, with little effect in winter. The major driver of post- harvest warming was an increase in solar radiation, which was partially moderated by the increased effects of hyporheic exchange, bed heat conduction and evaporation. Incorporating process-based measurements into paired-catchment experiments not only allows the causes of treatment response to be assessed, but they provide a valuable data set for testing predictive models.

  19. Retention and application of Skylab experiences to future programs. [a postflight review of technical programs.

    NASA Technical Reports Server (NTRS)

    Gillespie, V. G.; Kelly, R. O.

    1974-01-01

    The problems encountered and special techniques and procedures developed on the Skylab program are described along with the experiences and practical benefits obtained for dissemination and use on future programs. Three major topics are discussed: electrical problems, mechanical problems, and special techniques. Special techniques and procedures are identified that were either developed or refined during the Skylab program. These techniques and procedures came from all manufacturing and test phases of the Skylab program and include both flight and GSE items from component level to sophisticated spaceflight systems.

  20. Alternative-Specific and Case-Specific Factors Involved in the Decisions of Islamic School Teachers Affecting Teacher Retention: A Discrete Choice Experiment

    ERIC Educational Resources Information Center

    Abd-El-Hafez, Alaa Karem

    2015-01-01

    Teacher retention is a concern in all educational sectors in America. It is of special importance to Islamic schools, which tend to lack the resources necessary in recruiting and training new teachers. This dissertation addressed this problem in full-time Islamic schools in New York State by conducting a discrete choice experiment, which reflects…

  1. Examining the Academic Performance and Retention of First-Year Students in Living-Learning Communities and First-Year Experience Courses

    ERIC Educational Resources Information Center

    Purdie, John R., II; Rosser, Vicki J.

    2011-01-01

    Institutional data were used to examine the grades and retention of first-year students in 2 types of living learning communities--Academic Theme Floors (ATFs) and Freshman Interest Groups (FIGs)--and a First-Year Experience (FYE) course. Multiple regression revealed students in FIGs earned nominally higher GPAs (standardized [beta] = 0.02, p less…

  2. Considerations for the Use of the Observation Experience to Aid in Early Socialization and Retention of Athletic Training Students

    ERIC Educational Resources Information Center

    Mazerolle, Stephanie M.; Dodge, Thomas

    2014-01-01

    Context: Retention of quality students in athletic training programs (ATPs) is important. Many factors contribute to retention of students, including their motivation level, peer support, positive interactions with instructors, clinical integration, and mentorship. Objective: Highlight the use of the observation period for preparatory athletic…

  3. Understanding Alginate Gel Development for Bioclogging and Biogeophysical Experiments

    NASA Astrophysics Data System (ADS)

    Brown, I.; Atekwana, E. A.; Abdel Aal, G. Z.; Atekwana, E. A.; Sarkisova, S.; Patrauchan, M.

    2012-12-01

    Bioremediation strategies to mitigate the transport of heavy metals and radionuclides in subsurface sediments have largely targeted to increase the mobility and/or solubility of these compounds by the stimulation of biogeochemical activity of the metal- and sulfate-reducing bacteria. The latter secrete and/or release out diverse biochemical molecule including, first of all, organic acids and biopolymers such as alginic acid, proteins and DNA. Alginate gel is one of the major components determining the structure of biofilm which causes clogging in porous media. Biopolymers composing biofilm having, at least, two main functions: to be a scaffold for a microbial biofilm, and to regulate the exchange of metabolites and ions between an environment and bacterial cells. Additionally, the accumulation of biopolymers and a matured biofilm within porous media was shown to contribute to a detectable biogeophysical signal, spectral induced polarization (SIP), in particular. Our objective is to understand the role of different biofilm components on the SIP response as the latter has been proposed as a non-invasive tool to monitor biofilm development and rate of clogging in the subsurface. Understanding the process of alginate gel development may aid in the understanding of the fate and transport of mineralized heavy metals and radionuclides in contaminated soils. Here we describe the reciprocal relationship between environmental chemistry and alginate gel development. Commercial (Sigma) alginic acid (AA) was used as a substratum for the preparation of a model gel. AA was solubilized by adjusting solutions with pH up to 4 with 0.1 NaOH. Both Ca(OH)2 or CaCl2 were used to initiate the gelation of alginate. pH, fluid conductivity, soluble Ca2+ concentration, and a yield of gelated alginate were monitored in both liquid and porous media after the interaction of calcium compounds with alginate. This study confirms the critical role of Ca2+ for alginate gelation, biofilm development

  4. Understanding how social networking influences perceived satisfaction with conference experiences

    USGS Publications Warehouse

    van Riper, Carena J.; van Riper, Charles; Kyle, Gerard T.; Lee, Martha E.

    2013-01-01

    Social networking is a key benefit derived from participation in conferences that bind the ties of a professional community. Building social networks can lead to satisfactory experiences while furthering participants' long- and short-term career goals. Although investigations of social networking can lend insight into how to effectively engage individuals and groups within a professional cohort, this area has been largely overlooked in past research. The present study investigates the relationship between social networking and satisfaction with the 10th Biennial Conference of Research on the Colorado Plateau using structural equation modelling. Results partially support the hypothesis that three dimensions of social networking – interpersonal connections, social cohesion, and secondary associations – positively contribute to the performance of various conference attributes identified in two focus group sessions. The theoretical and applied contributions of this paper shed light on the social systems formed within professional communities and resource allocation among service providers.

  5. Epidural analgesia during labour - maternal understanding and experience - informed consent.

    PubMed

    Mahomed, K; Chin, D; Drew, A

    2015-01-01

    Women obtain information on epidural analgesia from various sources. For epidural for pain relief in labour this is provided by the anaesthetist as part of the consenting process. There is much discussion about the inadequacy of this consenting process; we report on women's knowledge, experience and recall of this process at a regional hospital with a 24-h epidural service. Fifty-four women were interviewed within 72 h of a vaginal birth. 91% of the women had acquired information from friends, relatives and antenatal classes. Lack of recall of benefits of epidural analgesia accounted for 26 (38%) and 25 (26%) of the responses, respectively. Similarly in terms of amount of pain relief they could expect, 13 (21%) could not remember and 13 (21%) thought that it may not work. We suggest use of varying methods of disseminating information and wider utilisation of anaesthetists in the antenatal educational programmes.

  6. Using discrete choice experiments to understand preferences in health care.

    PubMed

    Pfarr, Christian; Schmid, Andreas; Schneider, Udo

    2014-01-01

    Whenever processes are reconfigured or new products are designed the needs and preferences of patients and consumers have to be considered. Although at times neglected, this becomes more and more relevant in health care settings: Which modes of health care delivery will be accepted? What are the patients' priorities and what is the willingness to pay? To which degree are patients mobile and for which kind of services are they willing to travel? Preferences, however, are difficult to measure, as they are latent constructs. This becomes even more difficult, when no past choices can be analyzed either as the service or the product is yet to be developed or as in the past there has not been free choice for patients. In such cases, preferences cannot be surveyed directly. Asking individuals openly for their attitudes towards certain services and products, the results are likely biased as individuals are not confronted with budget constraints and trade-offs. For this reason, discrete choice experiments (DCEs) are frequently used to elicit patient preferences. This approach confronts patients with hypothetical scenarios of which only one can be chosen. Over the past few years, this tool to reveal patients' preferences for health care has become very popular in health economics. This contribution aims at introducing the principles of DCEs, highlighting the underlying theory and giving practical guidance for conducting a discrete choice experiment in health economics. Thereby we focus on three major fields of patient demand: designing health insurance, assessing patient utility of new pharmaceuticals and analyzing provider choice. By having a closer look at selected international studies, we discuss the application of this technique for the analysis of the supply and the demand of health care as well as the implications for assessing patient mobility across different health care systems.

  7. Understanding controlled drug release from mesoporous silicates: theory and experiment.

    PubMed

    Ukmar, T; Maver, U; Planinšek, O; Kaučič, V; Gaberšček, M; Godec, A

    2011-11-07

    Based on the results of carefully designed experiments upgraded with appropriate theoretical modeling, we present clear evidence that the release curves from mesoporous materials are significantly affected by drug-matrix interactions. In experimental curves, these interactions are manifested as a non-convergence at long times and an inverse dependence of release kinetics on pore size. Neither of these phenomena is expected in non-interacting systems. Although both phenomena have, rather sporadically, been observed in previous research, they have not been explained in terms of a general and consistent theoretical model. The concept is demonstrated on a model drug indomethacin embedded into SBA-15 and MCM-41 porous silicates. The experimental release curves agree exceptionally well with theoretical predictions in the case of significant drug-wall attractions. The latter are described using a 2D Fokker-Planck equation. One could say that the interactions affect the relative cross-section of pores where the local flux has a non-vanishing axial component and in turn control the effective transfer of drug into bulk solution. Finally, we identify the critical parameters determining the pore size dependence of release kinetics and construct a dynamic phase diagram of the various resulting transport regimes.

  8. Understanding Mixing and Entrainment of Oceanic Overflows Using Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Ecke, R. E.; Odier, P.; Chen, J.; Rivera, M. K.

    2007-12-01

    Oceanic overflows are important elements of the Earth's global thermohaline circulation but the mixing and entrainment that occur for such overflows is poorly understood. In particular, as overflow water moves down an inclined slope its stability is governed by the competition between stratification, which stabilizes the flow, and vertical shear, which tends to destabilize the flow. The properties of our laboratory experiment are designed to mimic oceanic overflows to the extent achievable on laboratory-accessible length scales. The flow exits a nozzle and flows along an inclined plane such that there is gravitational forcing of the flowing gravity current. We inject turbulent velocity fluctuations into the fluid using an active rotating grid prior to its exit from the nozzle, thereby generating a turbulent boundary layer condition at the plane boundary. The Taylor Reynolds number of the flow coming out of the nozzle is about 150. Velocity and density fields are measured simultaneous using particle image velocimetry and planar laser induced fluorescence. The flow structure and dynamics of mixing at different downstream locations are investigated for a standard stratified case and a non-stratified case where there is no density difference between the injected current and the ambient fluid. The role of turbulence is examined by comparing cases of turbulent and the laminar gravity currents. The implication of these results for ocean simulations will be presented.

  9. Assessment of selected bioretention blends for nutrient retention using mesocosm experiments.

    PubMed

    Liu, Jia; Sample, David J; Owen, James S; Li, Jinling; Evanylo, Gregory

    2014-09-01

    This study compares the performance of three bioretention media blends for N and P removal from simulated urban runoff in experimental mesocosms. TerraSolve, Biofilter, and "VT Mix" (Virginia Tech) were compared with and without vegetation at varying hydraulic residence times (HRTs). Adsorption isotherm experiments were also conducted. TerraSolve and VT Mix included water treatment residuals (WTRs), Biofilter and VT Mix included yard-waste compost (YWC), and TerraSolve included a mix of coir and peat. TerraSolve removed the highest amount of total P (>95%), which is attributed to the high quantity of WTRs. Results were similar for VT Mix, likely due to WTR content. Adsorption isotherms indicate a substantial difference due to this factor. Vegetative mesocosms were found to be less effective at P removal at an HRT of 6 to 12 h but not at an HRT of 24 h. VT Mix had the highest removal of total Kjeldahl nitrogen (TKN), significantly different than the other blends. Interactive effects with vegetation were observed, generally improving TKN removal at all HRTs, with the highest at 24 h. Substantial export of nutrients when using compost was not observed. The addition of YWC appeared to increase N removal, possibly by denitrification. It is recommended that bioretention media contain <10% fines, a source of amorphous Al for P adsorption, at least 3 to 5% total organic C in the form of a low P, relatively stable compost, and a minimum concentration of plant-available nutrients for establishment of vegetation. For systems that use HRT, optimum residence time is influenced by media composition.

  10. Wireless Participant Incentives Using Reloadable Bank Cards to Increase Clinical Trial Retention With Abused Women Drinkers: A Natural Experiment.

    PubMed

    Rodgers, Melissa; Meisel, Zachary; Wiebe, Douglas; Crits-Christoph, Paul; Rhodes, Karin V

    2016-08-07

    Retaining participants in longitudinal studies is a unique methodological challenge in many areas of investigation, and specifically for researchers aiming to identify effective interventions for women experiencing intimate partner violence (IPV). Individuals in abusive relationships are often transient and have logistical, confidentiality, and safety concerns that limit future contact. A natural experiment occurred during a large randomized clinical trial enrolling women in abusive relationships who were also heavy drinkers, which allowed for the comparison of two incentive methods to promote longitudinal retention: cash payment versus reloadable wireless bank cards. In all, 600 patients were enrolled in the overall trial, which aimed to incentivize participants using a reloadable bank card system to promote the completion of 11 weekly interactive voice response system (IVRS) phone surveys and 3-, 6-, and 12-month follow-up phone or in person interviews. The first 145 participants were paid with cash as a result of logistical delays in setting up the bank card system. At 12 weeks, participants receiving the bank card incentive completed significantly more IVRS phone surveys, odds ratio (OR) = 2.4, 95% confidence interval (CI) = [0.01, 1.69]. There were no significant differences between the two groups related to satisfaction or safety and/or privacy. The bank card system delivered lower administrative burden for tracking payments for study staff. Based on these and other results, our large medical research university is implementing reloadable bank card as the preferred method of participant incentive payments.

  11. Understanding

    ERIC Educational Resources Information Center

    Buxkemper, Andra C.; Hartfiel, D. J.

    2003-01-01

    There is no common agreement on the meaning of the word "understand". However, there is agreement on what students should be able to do with material they understand. Bloom et al. discuss kinds of tasks a student should be able to do, provided that the student understands. In a similar way, Biggs and Collis provide a taxonomy intended to evaluate…

  12. Impact of Experiments on 13-Year-Old Pupils' Understanding of Selected Science Concepts

    ERIC Educational Resources Information Center

    Urbancic, Matej; Glazar, Sasa A.

    2012-01-01

    The purpose of this study was to establish what impact experimental work has on the understanding of scientific concepts, what pupils remember about the experiments they carried out and how they are able to formulate and understand the experiment plan. A sample of 386 pupils aged 13+ participated in the research, of which 162 in the experimental…

  13. Children's Understanding of Ambiguous Figures: Which Cognitive Developments Are Necessary to Experience Reversal

    ERIC Educational Resources Information Center

    Doherty, M.J.; Wimmer, M.C.

    2005-01-01

    In two experiments involving one hundred and thirty-eight 3- to 5-year-olds we examined the claim that a complex understanding of ambiguity is required to experience reversal of ambiguous stimuli [Gopnik, A., & Rosati, A. (2001). Duck or rabbit? Reversing ambiguous figures and understanding ambiguous representations. Developmental Science, 4,…

  14. Cultural Immersion Experience: Promoting an Understanding of Mexican American Nutrition and Food Traditions

    ERIC Educational Resources Information Center

    Gilboy, Mary Beth; Bill, Debra E.

    2011-01-01

    A week long immersion experience in Guanajuato, Mexico provided an opportunity for public health and nutrition students to improve their understanding of Mexican culture, nutrition, and food traditions. The experience positively impacted the students' understanding of the importance of cultural sensitivity in working with the local Mexican…

  15. Medical genetics, public understanding and patient experiences: An exploratory qualitative study of recently pregnant women

    NASA Astrophysics Data System (ADS)

    Garman, Jamie L.

    The purpose of the study was to document how individuals' experiences and understanding of genetics concepts affects their medical experiences. Recently pregnant women were interviewed because they represent a population that needs to comprehend biological and genetic information to understand their health. Three women were designated as science experts (SE) defined as having extensive university level science education and three women were designated as science non-experts (SNE). In general, SEs described a more positive pregnancy experience. Both SEs and SNEs demonstrated a basic understanding of genetic concepts but varied in the application of concepts to personal medical issues. Participants' views and experiences of pre and postnatal tests were linked to their understanding of nature of science components such as recognition that tests have limitations. Results from this study indicate an incomplete understanding of the nature of science among participants may have led to unsatisfactory medical experiences.

  16. If We Admit Them, Will They Stay?: Understanding the Role of Social Connectedness in the Retention of African American Students in a Recreation and Leisure Studies Program

    ERIC Educational Resources Information Center

    Waller, Steven N.; Costen, Wanda M.; Wozencroft, Angela J.

    2011-01-01

    The retention of racial minority students lies at the core of diversity efforts instituted by colleges and universities across the nation. Withstanding the changing racial demographics of the U.S. and the need to have qualified racial minority professionals serving diverse communities retention and matriculation heighten in importance. With the…

  17. Understanding HBCU Retention and Completion

    ERIC Educational Resources Information Center

    Richards, David A. R.; Awokoya, Janet T.

    2012-01-01

    An appendix provides regression analyses.As the cost of higher education continues to climb, colleges and universities are finding themselves under increased pressure to demonstrate their value by enrolling, graduating and launching graduates into careers with the skills needed to compete as part of the American workforce. Few institutions are…

  18. Engaging Older Adults in High Impact Volunteering that Enhances Health: Recruitment and Retention in the Experience Corps® Baltimore

    PubMed Central

    Frick, Kevin; Glass, Thomas A.; Carlson, Michelle; Tanner, Elizabeth; Ricks, Michelle; Fried, Linda P.

    2006-01-01

    Engagement in social and generative activities has benefits for the well-being of older adults; hence, methods for broadly engaging them in such activities are desired. Experience Corps Baltimore, a social model for health promotion for older adult volunteers in public schools, offers insight to such successful recruitment and retention. We report on data over a 4-year period in Baltimore City, Maryland, and describe a five-stage screening process implemented to recruit a diverse group of senior volunteers who would remain in the program for at least 1 year. The sample consisted of 443 older adults expressing an interest in and screened for volunteering. Comparisons were made with Chi-square and Fisher’s t-test between those who entered the program and those who did not and those who were retained in the program. Gender, race, age group, and prior volunteering were significant in ultimate volunteer service in the schools. Overall, 38% of 443 persons recruited entered the schools; 94% of participants were over 60 years (p = 0.05) with a mean age of 69 years; 90% were women (p = 0.03), and 93% African-American (p = 0.005); 57% had not volunteered in the past year (p = 0.004). Ninety-two percent were retained in the first year; 80% returned a second year. Among the latter, 83% had <12 years of education (p = 0.001). Participants remained in the program for a second year of volunteering regardless of baseline MMSE score, self-reported health, and motivation for volunteering. In conclusion, it is possible to recruit and retain a diverse pool of older adults to participate in a high-intensity volunteer program, including non-traditional volunteers. Of special note is the success in recruiting African-American women and those with lower education, who may particularly benefit from health promotion. PMID:16758336

  19. Engaging older adults in high impact volunteering that enhances health: recruitment and retention in The Experience Corps Baltimore.

    PubMed

    Martinez, Iveris L; Frick, Kevin; Glass, Thomas A; Carlson, Michelle; Tanner, Elizabeth; Ricks, Michelle; Fried, Linda P

    2006-09-01

    Engagement in social and generative activities has benefits for the well-being of older adults; hence, methods for broadly engaging them in such activities are desired. Experience Corps Baltimore, a social model for health promotion for older adult volunteers in public schools, offers insight to such successful recruitment and retention. We report on data over a 4-year period in Baltimore City, Maryland, and describe a five-stage screening process implemented to recruit a diverse group of senior volunteers who would remain in the program for at least 1 year. The sample consisted of 443 older adults expressing an interest in and screened for volunteering. Comparisons were made with Chi-square and Fisher's t-test between those who entered the program and those who did not and those who were retained in the program. Gender, race, age group, and prior volunteering were significant in ultimate volunteer service in the schools. Overall, 38% of 443 persons recruited entered the schools; 94% of participants were over 60 years (p = 0.05) with a mean age of 69 years; 90% were women (p = 0.03), and 93% African-American (p = 0.005); 57% had not volunteered in the past year (p = 0.004). Ninety-two percent were retained in the first year; 80% returned a second year. Among the latter, 83% had <12 years of education (p = 0.001). Participants remained in the program for a second year of volunteering regardless of baseline MMSE score, self-reported health, and motivation for volunteering. In conclusion, it is possible to recruit and retain a diverse pool of older adults to participate in a high-intensity volunteer program, including non-traditional volunteers. Of special note is the success in recruiting African-American women and those with lower education, who may particularly benefit from health promotion.

  20. Retention of habitat complexity minimizes disassembly of reef fish communities following disturbance: a large-scale natural experiment.

    PubMed

    Emslie, Michael J; Cheal, Alistair J; Johns, Kerryn A

    2014-01-01

    High biodiversity ecosystems are commonly associated with complex habitats. Coral reefs are highly diverse ecosystems, but are under increasing pressure from numerous stressors, many of which reduce live coral cover and habitat complexity with concomitant effects on other organisms such as reef fishes. While previous studies have highlighted the importance of habitat complexity in structuring reef fish communities, they employed gradient or meta-analyses which lacked a controlled experimental design over broad spatial scales to explicitly separate the influence of live coral cover from overall habitat complexity. Here a natural experiment using a long term (20 year), spatially extensive (∼ 115,000 kms(2)) dataset from the Great Barrier Reef revealed the fundamental importance of overall habitat complexity for reef fishes. Reductions of both live coral cover and habitat complexity had substantial impacts on fish communities compared to relatively minor impacts after major reductions in coral cover but not habitat complexity. Where habitat complexity was substantially reduced, species abundances broadly declined and a far greater number of fish species were locally extirpated, including economically important fishes. This resulted in decreased species richness and a loss of diversity within functional groups. Our results suggest that the retention of habitat complexity following disturbances can ameliorate the impacts of coral declines on reef fishes, so preserving their capacity to perform important functional roles essential to reef resilience. These results add to a growing body of evidence about the importance of habitat complexity for reef fishes, and represent the first large-scale examination of this question on the Great Barrier Reef.

  1. Causes and implications of colloid and microorganism retention hysteresis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Experiments were designed to better understand the causes and implications of colloid and microorganism retention hysteresis with transients in solution ionic strength (IS). Saturated packed column experiments were conducted using two sizes of carboxyl modified latex (CML) microspheres (0.1 and 1.1...

  2. Mentorship: increasing retention probabilities.

    PubMed

    Leners, Debra Woodard; Wilson, Vicki W; Connor, Peggy; Fenton, Joanne

    2006-11-01

    Retaining nurses is a significant workforce issue. Experienced nurses in particular are getting harder to retain within hospitals and the discipline at large. One solution to boost retention is to give serious attention to professional socialization activities through contemporary nurse mentorship experiences. The authors contend that contemporary mentoring programmes, targeting developmental quality of life issues of the expert nurse, would appreciably benefit retention programmes within the hospital environment.

  3. Understanding the Complexity of Porous Graphitic Carbon (PGC) Chromatography: Modulation of Mobile-Stationary Phase Interactions Overcomes Loss of Retention and Reduces Variability

    PubMed Central

    2016-01-01

    Porous graphitic carbon (PGC) is an important tool in a chromatographer’s armory that retains polar compounds with mass spectrometry (MS)-compatible solvents. However, its applicability is severely limited by an unpredictable loss of retention, which can be attributed to contamination. The solutions offered fail to restore the original retention and our observations of retention time shifts of gemcitabine/metabolites on PGC are not consistent with contamination. The mobile phase affects the ionization state of analytes and the polarizable PGC surface that influences the strength of dispersive forces governing retention on the stationary phase. We hypothesized that failure to maintain the same PGC surface before and after running a gradient is a cause of the observed retention loss/variability on PGC. Herein, we optimize the choice of mobile phase solvent in a gradient program with three parts: a preparatory phase, which allows binding of analytes to column; an elution phase, which gives the required separation/peak shape; and a maintenance phase, to preserve the required retention capacity. Via liquid chromatography/tandem mass spectrometry (LC-MS/MS) analysis of gemcitabine and its metabolites extracted from tumor tissue, we demonstrate reproducible chromatography on three PGC columns of different ages. This approach simplifies use of the PGC to the same level as that of a C-18 column, removes the need for column regeneration, and minimizes run times, thus allowing PGC columns to be used to their full potential. PMID:27228284

  4. Understanding the African-American Student Experience in Higher Education through a Relational Dialectics Perspective

    ERIC Educational Resources Information Center

    Simmons, Jake; Lowery-Hart, Russell; Wahl, Shawn T.; McBride, M. Chad

    2013-01-01

    In this study, we sought to understand African-American students' higher-education experiences in predominantly White universities. We utilized Baxter's relational dialectics theory to study components of focus-group discussions in order to understand the discourse and meaning-making process of participants. Our findings provide insight into the…

  5. Teacher's Understanding, Perceptions, and Experiences of Students in Foster Care: A Forgotten Population

    ERIC Educational Resources Information Center

    Watson-Davis, Darneika

    2010-01-01

    The purpose of this study is to examine elementary teacher's understanding, perceptions, and experiences of working with students in foster care. The researcher examined whether teachers are informed about students in foster care, determined teacher's understanding of the foster care system, and how their students are affected. The results…

  6. Subject- and Experience-Bound Differences in Teachers' Conceptual Understanding of Sustainable Development

    ERIC Educational Resources Information Center

    Borg, C.; Gericke, N.; Höglund, H.-O.; Bergman, E.

    2014-01-01

    This article describes the results of a nationwide questionnaire study of 3229 Swedish upper secondary school teachers' conceptual understanding of sustainable development in relation to their subject discipline and teaching experience. Previous research has shown that teachers have difficulties understanding the complex concept of sustainable…

  7. Particulate organic matter quality influences nitrate retention and denitrification in stream sediments: evidence from a carbon burial experiment

    USGS Publications Warehouse

    Stelzer, Robert S.; Scott, J. Thad; Bartsch, Lynn; Parr, Thomas B.

    2014-01-01

    Organic carbon supply is linked to nitrogen transformation in ecosystems. However, the role of organic carbon quality in nitrogen processing is not as well understood. We determined how the quality of particulate organic carbon (POC) influenced nitrogen transformation in stream sediments by burying identical quantities of varying quality POC (northern red oak (Quercus rubra) leaves, red maple (Acer rubrum) leaves, red maple wood) in stream mesocosms and measuring the effects on nitrogen retention and denitrification compared to a control of combusted sand. We also determined how POC quality affected the quantity and quality of dissolved organic carbon (DOC) and dissolved oxygen concentration in groundwater. Nitrate and total dissolved nitrogen (TDN) retention were assessed by comparing solute concentrations and fluxes along groundwater flow paths in the mesocosms. Denitrification was measured by in situ changes in N2 concentrations (using MIMS) and by acetylene block incubations. POC quality was measured by C:N and lignin:N ratios and DOC quality was assessed by fluorescence excitation emission matrix spectroscopy. POC quality had strong effects on nitrogen processing. Leaf treatments had much higher nitrate retention, TDN retention and denitrification rates than the wood and control treatments and red maple leaf burial resulted in higher nitrate and TDN retention rates than burial of red oak leaves. Leaf, but not wood, burial drove pore water to severe hypoxia and leaf treatments had higher DOC production and different DOC chemical composition than the wood and control treatments. We think that POC quality affected nitrogen processing in the sediments by influencing the quantity and quality of DOC and redox conditions. Our results suggest that the type of organic carbon inputs can affect the rates of nitrogen transformation in stream ecosystems.

  8. Understanding the Experience of Being Taught by Peers: The Value of Social and Cognitive Congruence

    ERIC Educational Resources Information Center

    Lockspeiser, Tai M.; O'Sullivan, Patricia; Teherani, Arianne; Muller, Jessica

    2008-01-01

    Background: Medical schools use supplemental peer-teaching programs even though there is little research on students' actual experiences with this form of instruction. Purpose: To understand the student experience of being taught by peers instead of by faculty. Methods: We conducted focus groups with first- and second-year medical students…

  9. A Phenomenological Study into How Students Experience and Understand the University Presidency

    ERIC Educational Resources Information Center

    Schuemann, Kahler B.

    2014-01-01

    Little is known about how college students experience and understand the university presidency. Students are important consumers of the academic experience and by affiliation are constituents of organizational leadership. The social distance between students and university presidents continues to narrow. To address the void in scholarly…

  10. Real Experiments versus Phet Simulations for Better High-School Students' Understanding of Electrostatic Charging

    ERIC Educational Resources Information Center

    Ajredini, Fadil; Izairi, Neset; Zajkov, Oliver

    2014-01-01

    This research investigates the influence of computer simulations (virtual experiments) on one hand and real experiments on the other hand on the conceptual understanding of electrical charging. The investigated sample consists of students in the second year (10th grade) of three gymnasiums in Macedonia. There were two experimental groups and one…

  11. Understanding the Experience of College Graduates during Their First Year of Employment

    ERIC Educational Resources Information Center

    Polach, Janet L.

    2004-01-01

    A company's college recruitment practices, as well as its socialization processes for graduates once they have joined the organization, can be improved when there is understanding of college graduates' experience during the first year of employment. This study recorded the experiences of eight college graduates who were employed by a medical…

  12. Multicultural and Cross-Cultural Narrative Inquiry into Understanding Immigrant Students' Educational Experience in Hong Kong

    ERIC Educational Resources Information Center

    Phillion, JoAnn

    2008-01-01

    The purpose of this paper is to explore the potential of narrative inquiry to contribute to an understanding of immigrant students' educational experience. Research on immigrant students' education is reviewed and the need for detailed examination of these students' experiences in schools, such as is done in a narrative inquiry, is demonstrated.…

  13. Job Satisfaction of New Teachers in Malaysia: Understanding Challenges and Experiences of Leaving the Profession

    ERIC Educational Resources Information Center

    Jusoh, Ruzina binti

    2012-01-01

    This study focuses on new teachers' job satisfaction and their challenges and experiences during their probationary period. This research concentrated on how their challenges and experiences affected their choice to leave the profession. Basic Interpretive Qualitative method was utilized to explore and understand new teachers' challenges and…

  14. Education as Service: The Understanding of University Experience through the Service Logic

    ERIC Educational Resources Information Center

    Ng, Irene C. L.; Forbes, Jeannie

    2009-01-01

    With the marketization of UK higher education, this paper develops a framework from services marketing that can assist universities in understanding what market orientation means and how students would value their offerings. Our study shows that the core service in a university experience is a learning experience that is cocreated and that the…

  15. Effects of Experimenting with Physical and Virtual Manipulatives on Students' Conceptual Understanding in Heat and Temperature

    ERIC Educational Resources Information Center

    Zacharia, Zacharias C.; Olympiou, Georgios; Papaevripidou, Marios

    2008-01-01

    This study aimed to investigate the comparative value of experimenting with physical manipulatives (PM) in a sequential combination with virtual manipulatives (VM), with the use of PM preceding the use of VM, and of experimenting with PM alone, with respect to changes in students' conceptual understanding in the domain of heat and temperature. A…

  16. Ten experiments that would make a difference in understanding immune mechanisms.

    PubMed

    Cohn, Melvin

    2012-02-01

    Jacques Monod used to say, "Never trust an experiment that is not supported by a good theory." Theory or conceptualization permits us to put order or structure into a vast amount of data in a way that increases understanding. Validly competing theories are most useful when they make testably disprovable predictions. Illustrating the theory-experiment interaction is the goal of this exercise. Stated bleakly, the answers derived from the theory-based experiments described here would impact dramatically on how we understand immune behavior.

  17. Beyond Academic and Social Integration: Understanding the Impact of a STEM Enrichment Program on the Retention and Degree Attainment of Underrepresented Students

    ERIC Educational Resources Information Center

    Lane, Tonisha B.

    2016-01-01

    The current study used a case study methodological approach, including document analysis, semistructured interviews, and participant observations, to investigate how a science, technology, engineering, and mathematics (STEM) enrichment program supported retention and degree attainment of underrepresented students at a large, public, predominantly…

  18. Rapid Method Development in Hydrophilic Interaction Liquid Chromatography for Pharmaceutical Analysis Using a Combination of Quantitative Structure-Retention Relationships and Design of Experiments.

    PubMed

    Taraji, Maryam; Haddad, Paul R; Amos, Ruth I J; Talebi, Mohammad; Szucs, Roman; Dolan, John W; Pohl, Chris A

    2017-02-07

    A design-of-experiment (DoE) model was developed, able to describe the retention times of a mixture of pharmaceutical compounds in hydrophilic interaction liquid chromatography (HILIC) under all possible combinations of acetonitrile content, salt concentration, and mobile-phase pH with R(2) > 0.95. Further, a quantitative structure-retention relationship (QSRR) model was developed to predict retention times for new analytes, based only on their chemical structures, with a root-mean-square error of prediction (RMSEP) as low as 0.81%. A compound classification based on the concept of similarity was applied prior to QSRR modeling. Finally, we utilized a combined QSRR-DoE approach to propose an optimal design space in a quality-by-design (QbD) workflow to facilitate the HILIC method development. The mathematical QSRR-DoE model was shown to be highly predictive when applied to an independent test set of unseen compounds in unseen conditions with a RMSEP value of 5.83%. The QSRR-DoE computed retention time of pharmaceutical test analytes and subsequently calculated separation selectivity was used to optimize the chromatographic conditions for efficient separation of targets. A Monte Carlo simulation was performed to evaluate the risk of uncertainty in the model's prediction, and to define the design space where the desired quality criterion was met. Experimental realization of peak selectivity between targets under the selected optimal working conditions confirmed the theoretical predictions. These results demonstrate how discovery of optimal conditions for the separation of new analytes can be accelerated by the use of appropriate theoretical tools.

  19. Financial Literacy and Retention

    ERIC Educational Resources Information Center

    Adams, Ruth L.

    2006-01-01

    Higher education administrators know it is more cost-effective to keep students than to recruit them. Understanding financial literacy--and how it impacts student retention and persistence on the campuses--is an important concept for administrators to comprehend. Most students are not financially literate when they enter the world of higher…

  20. Understanding experience through Gadamerian hermeneutics: an interview with Brian Phillips. Interview by Pamela Wood & Lynne Giddings.

    PubMed

    Phillips, Brian

    2005-07-01

    Hermeneutic approaches to research focus on understanding and interpretation of experience but differ in process and emphasis. Gadamerian hermeneutics concentrates on expanding horizons of understanding through dialogue, between people or between a researcher and texts, in which taken-for-granted assumptions are examined and opinions willingly put at risk. This article is the fourteenth in a series of articles based on interviews with nursing and midwifery researchers, designed to offer the beginning researcher a first-hand account of the experience of using particular methodologies. It considers a Gadamerian hermeneutic research approach as interpreted by Brian Phillips (RN, PhD) in interview. Brian is Research Fellow in the Graduate School of Nursing and Midwifery at Victoria University of Wellington. For his PhD research Brian used Gadamerian hermeneutics to interpret four men's experiences of suicidality and the ideas of masculinity that might have shaped their understandings.

  1. What are you doing? How active and observational experience shape infants' action understanding

    PubMed Central

    Hunnius, Sabine; Bekkering, Harold

    2014-01-01

    From early in life, infants watch other people's actions. How do young infants come to make sense of actions they observe? Here, we review empirical findings on the development of action understanding in infancy. Based on this review, we argue that active action experience is crucial for infants' developing action understanding. When infants execute actions, they form associations between motor acts and the sensory consequences of these acts. When infants subsequently observe these actions in others, they can use their motor system to predict the outcome of the ongoing actions. Also, infants come to an understanding of others’ actions through the repeated observation of actions and the effects associated with them. In their daily lives, infants have plenty of opportunities to form associations between observed events and learn about statistical regularities of others’ behaviours. We argue that based on these two forms of experience—active action experience and observational experience—infants gradually develop more complex action understanding capabilities. PMID:24778386

  2. Promoting Retention

    PubMed Central

    Hall, LaToya N.; Ficker, Lisa J.; Chadiha, Letha A.; Green, Carmen R.; Jackson, James S.; Lichtenberg, Peter A.

    2016-01-01

    Objectives: The objectives of this study were to evaluate the capability of a research volunteer registry to retain community-dwelling African American older adults, and to explore demographic and health factors associated with retention. Method: A logistic regression model was used to determine the influence of demographics, health factors, and registry logic model activities on retention in a sample of 1,730 older African American adults. Results: Almost 80% of participants active in the volunteer research registry between January 2012 and June 2015 were retained. Employment, being referred to research studies, a higher number of medical conditions, and more follow-up contacts were associated with an increased likelihood of retention. Older age, more months in the registry, and more mobility problems decreased the likelihood of retention. Discussion: These results suggest the Michigan Center for Urban African American Aging Research logic model promotes retention through involving older African American adults in research through study referrals and intensive follow-up. The loss of participants due to age- and mobility-related issues indicate the registry may be losing its most vulnerable participants. PMID:28138501

  3. How Students "Stay the Course": Retention Practices in Higher Education

    ERIC Educational Resources Information Center

    Kurantowicz, Ewa; Nizinska, Adrianna

    2013-01-01

    The article is based on the results of research carried out under the RANLHE project in several Polish academic institutions. Applying the biographical research approach, the project aimed to explore and understand the access and retention-related experiences of non-traditional students. In a study of non-traditional students, three distinct…

  4. Using artwork to understand the experience of mental illness: Mainstream artists and Outsider artists

    PubMed Central

    Rustin, Terry A.

    2008-01-01

    Objective: Artwork and psychiatric disorders are often linked. Accomplished artists with psychiatric disorders express themselves and their emotional distress through their works, and art therapists use the visual arts to help clients understand their problems and cope with them. There have been a number of psychiatric patients with no previous art training who produced artwork that many consider museum-worthy (Art Brut, or Outsider Art.) For the past two years, I have used artwork in another way: to better understand my clients and their psychiatric disorders. Methods: Presented here are paintings I have made about the mental illness experience of some of my clients, all well known to me through their therapy. It is a form of visual psychodrama, in which I reverse roles with the client through the paintings. My goal has been to experience the stresses felt by my clients so that I can understand them better. Results: The paintings have served as a point of embarkation for therapy sessions, as a means of clarifying a client’s experience, and as a way to show clients that their therapist is attending to what they say. Countertransference undoubtedly plays a role in my choice of clients and their portrayals, but the intent is to help me better understand the clients’ experiences. Included here are images of some of these paintings with a short psychiatric history of the client about whom they were made. Accompanying each one are responses from the clients upon viewing “their” paintings, and a discussion of the client’s psychiatric disorder. Conclusions: Making these paintings has helped me understand better the feelings of isolation, rejection, loss, and alienation that many of my clients experience every day. In turn, they tell me that viewing the paintings is an intense experience for them as well. As an outsider artist, I must leave it to the viewer to determine whether or not these paintings qualify as “art.” PMID:19742284

  5. A Conceptual Model to Promote the Retention of Women With Physical Disabilities in Research

    PubMed Central

    Mood, Laura; Hassouneh, Dena; McNeff, Elizabeth

    2015-01-01

    Inadequate participant recruitment and retention practices can affect sample representativeness and thus the generalizability of research findings. Retention of research participants has been examined within the literature to some extent; however, there is no consensus on best practice in achieving acceptable results. Furthermore, there is a gap in understanding how to engage and retain women with physical disabilities (WPDs) in research. To address these oversights, we review (1) the significance of retention as a methodologic concern, (2) factors that influence the involvement and retention of participants in research, including individual, population, and health-illness considerations, and (3) particular circumstances impacting the inclusion and retention of WPDs in research. Based on a review of the literature and our experience with the Healing Pathways randomized-controlled trial (RCT), we present a conceptual model to guide culturally-sensitive health research implementation with WPDs, and promote the engagement and retention of this group in RCTs and other forms of interventional health research. PMID:25801324

  6. A Practical Example Aiding Understanding Momentum in 1D: The Water Gun Experiment

    ERIC Educational Resources Information Center

    MacLeod, Katarin

    2007-01-01

    The law of conservation of momentum is one that students often have difficulties understanding. This experiment allows students to use childhood toys to examine and calculate the muzzle velocity of their favourite water gun by using an air track, a spark timer or data logger and the law of conservation of momentum in a one-dimensional case, a…

  7. Voices of Experience: Understanding and Enhancing Successful Conflict Management by Community College Presidents

    ERIC Educational Resources Information Center

    Zanjani, Mellissia M.

    2012-01-01

    The purpose of this research study was to enhance understanding of successful conflict management by community college Presidents through highlighting and describing conflict experiences with the faculty union or the board of trustees in a community college context. The following questions guided the research: (a) How do community college…

  8. Digital Journeys: A Perspective on Understanding the Digital Experiences of International Students

    ERIC Educational Resources Information Center

    Chang, Shanton; Gomes, Catherine

    2017-01-01

    The authors in this conceptual paper draw on the literature on information seeking behavior, social media use, and international student experiences to propose Digital Journeys as a framework which helps us understand the online behavior of international students. Here we theorize that the Digital Journey is the transition that individuals make…

  9. Understanding the Online Doctoral Learning Experience: Factors That Contribute to Students' Sense of Community

    ERIC Educational Resources Information Center

    Byrd, Jeremy Carl

    2016-01-01

    As the number of students taking online courses continues to grow steadily, it is becoming increasingly important to inquire about the experiences of these students in order to understand the factors that contribute to their success. It is imperative that the social needs of students be understood, as interaction is an important aspect of the…

  10. The Puerto Rican Prison Experience: A Multicultural Understanding of Values, Beliefs, and Attitudes.

    ERIC Educational Resources Information Center

    Rivera, Edil Torres; Wilbur, Michael P.; Roberts-Wilbur, Janice

    1998-01-01

    Counselors are challenged to use a nontraditional, multicultural approach with Puerto Rican inmates, to strive to understand their values, beliefs, experiences, and behaviors; and to question their own underlying assumptions and linear models of therapy. Five specific recommendations are made, and a comparison of beliefs and values is appended.…

  11. The Cavendish Experiment as a Tool for Historical Understanding of Science

    ERIC Educational Resources Information Center

    Ducheyne, Steffen

    2012-01-01

    Following an ever growing literature which takes serious the relevance of case-studies in the history of science for science education and understanding of science, I provide a detailed historical reconstruction of the Cavendish Experiment, which remains as close as possible to the original. In this paper, I call attention to three educational…

  12. Navigating the Transition to Community College: Understanding the Perceptions and Strategies Related to Latina Experiences

    ERIC Educational Resources Information Center

    Martinez-Vogt, Emily

    2014-01-01

    The transition of Latina community college students warrants further interest from the research community and this study aims to fill a gap in the research by examining the transition experiences from the voices of Latina community college students. The purpose of this qualitative study was to understand Latina community college students'…

  13. Using Online Tools for Communication and Collaboration: Understanding Educators' Experiences in an Online Course

    ERIC Educational Resources Information Center

    Boling, Erica C.; Holan, Erica; Horbatt, Brent; Hough, Mary; Jean-Louis, Jennifer; Khurana, Chesta; Krinsky, Hindi; Spiezio, Christina

    2011-01-01

    This designed-based research study explored educators' experiences in an online course to better understand how course design and pedagogical delivery can best support student learning. Using the Cognitive Apprenticeship Model (Collins et al., 1987) as a theoretical lens, researchers investigated the following: 1) What methods of instruction, as…

  14. Students' Understanding of Analogy after a Core (Chemical Observations, Representations, Experimentation) Learning Cycle, General Chemistry Experiment

    ERIC Educational Resources Information Center

    Avargil, Shirly; Bruce, Mitchell R. M.; Amar, Franc¸ois G.; Bruce, Alice E.

    2015-01-01

    Students' understanding about analogy was investigated after a CORE learning cycle general chemistry experiment. CORE (Chemical Observations, Representations, Experimentation) is a new three-phase learning cycle that involves (phase 1) guiding students through chemical observations while they consider a series of open-ended questions, (phase 2)…

  15. Children's experiences of food insecurity can assist in understanding its effect on their well-being

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An understanding of the experience of food insecurity by children is essential for better measurement and assessment of its effect on children's nutritional, physical, and mental health. Our qualitative study explored children's perceptions of household food insecurity to identify these perceptions ...

  16. Understanding the Experience of CACREP On-Site Visiting Review Team Chairpersons

    ERIC Educational Resources Information Center

    Minor, Amanda J.

    2012-01-01

    Understanding the experience of CACREP on-site review team members provides insight into the phenomenon of four counselor educators who have each served as a CACREP on-site visiting review team chairperson a minimum of three times. In total, the participants had been within the counselor education field for approximately 95 years and active within…

  17. Areas Recruited during Action Understanding Are Not Modulated by Auditory or Sign Language Experience

    PubMed Central

    Fang, Yuxing; Chen, Quanjing; Lingnau, Angelika; Han, Zaizhu; Bi, Yanchao

    2016-01-01

    The observation of other people’s actions recruits a network of areas including the inferior frontal gyrus (IFG), the inferior parietal lobule (IPL), and posterior middle temporal gyrus (pMTG). These regions have been shown to be activated through both visual and auditory inputs. Intriguingly, previous studies found no engagement of IFG and IPL for deaf participants during non-linguistic action observation, leading to the proposal that auditory experience or sign language usage might shape the functionality of these areas. To understand which variables induce plastic changes in areas recruited during the processing of other people’s actions, we examined the effects of tasks (action understanding and passive viewing) and effectors (arm actions vs. leg actions), as well as sign language experience in a group of 12 congenitally deaf signers and 13 hearing participants. In Experiment 1, we found a stronger activation during an action recognition task in comparison to a low-level visual control task in IFG, IPL and pMTG in both deaf signers and hearing individuals, but no effect of auditory or sign language experience. In Experiment 2, we replicated the results of the first experiment using a passive viewing task. Together, our results provide robust evidence demonstrating that the response obtained in IFG, IPL, and pMTG during action recognition and passive viewing is not affected by auditory or sign language experience, adding further support for the supra-modal nature of these regions. PMID:27014025

  18. Areas Recruited during Action Understanding Are Not Modulated by Auditory or Sign Language Experience.

    PubMed

    Fang, Yuxing; Chen, Quanjing; Lingnau, Angelika; Han, Zaizhu; Bi, Yanchao

    2016-01-01

    The observation of other people's actions recruits a network of areas including the inferior frontal gyrus (IFG), the inferior parietal lobule (IPL), and posterior middle temporal gyrus (pMTG). These regions have been shown to be activated through both visual and auditory inputs. Intriguingly, previous studies found no engagement of IFG and IPL for deaf participants during non-linguistic action observation, leading to the proposal that auditory experience or sign language usage might shape the functionality of these areas. To understand which variables induce plastic changes in areas recruited during the processing of other people's actions, we examined the effects of tasks (action understanding and passive viewing) and effectors (arm actions vs. leg actions), as well as sign language experience in a group of 12 congenitally deaf signers and 13 hearing participants. In Experiment 1, we found a stronger activation during an action recognition task in comparison to a low-level visual control task in IFG, IPL and pMTG in both deaf signers and hearing individuals, but no effect of auditory or sign language experience. In Experiment 2, we replicated the results of the first experiment using a passive viewing task. Together, our results provide robust evidence demonstrating that the response obtained in IFG, IPL, and pMTG during action recognition and passive viewing is not affected by auditory or sign language experience, adding further support for the supra-modal nature of these regions.

  19. Urinary Retention

    MedlinePlus

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

  20. Retention Checklist.

    ERIC Educational Resources Information Center

    Santa Rita, Emilio

    Designed to improve student retention at Bronx Community College (BCC), this workbook is comprised of sets checklists for use by students in evaluating their progress toward a number of academic, personal, and work-related goals. The workbook is divided into five sections, each containing a set of goals and associated checklists. Part I deals with…

  1. Beyond Academic and Social Integration: Understanding the Impact of a STEM Enrichment Program on the Retention and Degree Attainment of Underrepresented Students

    PubMed Central

    Lane, Tonisha B.

    2016-01-01

    The current study used a case study methodological approach, including document analysis, semistructured interviews, and participant observations, to investigate how a science, technology, engineering, and mathematics (STEM) enrichment program supported retention and degree attainment of underrepresented students at a large, public, predominantly white institution. From this study, a model emerged that encompassed four components: proactive care, holistic support, community building, and catalysts for STEM identity development. These components encompassed a number of strategies and practices that were instrumental in the outcomes of program participants. This paper concludes with implications for practice, such as using models to inform program planning, assessment, and evaluation. PMID:27543638

  2. Beyond Academic and Social Integration: Understanding the Impact of a STEM Enrichment Program on the Retention and Degree Attainment of Underrepresented Students.

    PubMed

    Lane, Tonisha B

    2016-01-01

    The current study used a case study methodological approach, including document analysis, semistructured interviews, and participant observations, to investigate how a science, technology, engineering, and mathematics (STEM) enrichment program supported retention and degree attainment of underrepresented students at a large, public, predominantly white institution. From this study, a model emerged that encompassed four components: proactive care, holistic support, community building, and catalysts for STEM identity development. These components encompassed a number of strategies and practices that were instrumental in the outcomes of program participants. This paper concludes with implications for practice, such as using models to inform program planning, assessment, and evaluation.

  3. Tablets in trauma: using mobile computing platforms to improve patient understanding and experience.

    PubMed

    Furness, Nicholas D; Bradford, Oliver J; Paterson, Maurice P

    2013-03-01

    Tablets are becoming commonplace in the health care setting. Patients often request to view their radiographs after sustaining trauma. This can be challenging, especially if patients are immobile. The authors performed a prospective, questionnaire-based study to assess inpatient desire to view radiographs on tablets and whether viewing images affected patient-rated outcomes of understanding and satisfaction. Enabling trauma patients to view their images on a tablet is a worthwhile practice because it improves patient involvement in decision making, satisfaction, perceived understanding, and overall experience.

  4. Involvement in Campus Activities and the Retention of First-Year College Students. The First-Year Experience Monograph Series.

    ERIC Educational Resources Information Center

    Skipper, Tracy L., Ed.; Argo, Roxanne, Ed.

    The chapters of this monograph offer insights into educationally purposeful out-of-class activities and the impact they have on the student experience. It also provides future directions for the campus activities field and identifies ways to improve the educational experience of first-year students to enhance their scholarly experience and to…

  5. Improved understanding of geologic CO{sub 2} storage processes requires risk-driven field experiments

    SciTech Connect

    Oldenburg, C.M.

    2011-06-01

    The need for risk-driven field experiments for CO{sub 2} geologic storage processes to complement ongoing pilot-scale demonstrations is discussed. These risk-driven field experiments would be aimed at understanding the circumstances under which things can go wrong with a CO{sub 2} capture and storage (CCS) project and cause it to fail, as distinguished from accomplishing this end using demonstration and industrial scale sites. Such risk-driven tests would complement risk-assessment efforts that have already been carried out by providing opportunities to validate risk models. In addition to experimenting with high-risk scenarios, these controlled field experiments could help validate monitoring approaches to improve performance assessment and guide development of mitigation strategies.

  6. Curriculum development through understanding the student nurse experience of suicide intervention education--A phenomenographic study.

    PubMed

    Heyman, Inga; Webster, Brian J; Tee, Stephen

    2015-11-01

    Suicide remains a global public health issue and a major governmental concern. The World Health Organisation argues for continued investment in education for front-line professionals, with a particular focus on nurses, to address the rising suicide levels. Considering this rate, it could be argued that suicide has impacted on the lives of many, including the student nurse population. Understanding the psychological impact, and influence on learning, whilst developing suicide intervention knowledge is crucial. However, little is known of the student experience in this complex and challenging area of skills development. This phenomenographic study examines the experiences of second year Bachelor of Nursing (mental health) students who participated in the Applied Suicide Intervention Skills Training (ASIST). Experiences were illuminated through two focus groups, Experiences were distilled and categorised through hierarchically relationships to construct a group experiential field to illustrate understandings of the impact this approach has on learning Students found ASIST to be emotionally challenging yet an extremely positive experience through bonding, peer learning, and class cohesion. The supportive workshop facilitation was essential allowing for full immersion into role simulation thus developing student confidence. Appropriate pedagogy and student support must be considered whilst developing suicide intervention in the pre-registration curricula.

  7. Observing women caregivers' everyday experiences: new ways of understanding and intervening.

    PubMed

    Silverman, Marjorie

    2015-01-01

    This article discusses the practice implications of videographic research examining the everyday lived experiences of 5 women family caregivers of older adults with chronic illness. The women's nonverbal expressions and gestures revealed how caregiving is accomplished and lived on a daily basis, in particular through emotion and body management, abnegation, and performance. The findings from this microethnographic study suggest that observing women caregivers' everyday experiences can open new avenues for holistic intervention with this population. Observing nonverbal cues can offer a way for practitioners to better understand women caregivers' realities, to question their practice, and to adapt their interventions accordingly.

  8. Understanding the Experiences of Youth Living with Sickle Cell Disease: A Photovoice Pilot

    PubMed Central

    Valenzuela, Jessica M.; Vaughn, Lisa M.; Crosby, Lori E.; Strong, Heather; Kissling, Alexandra; Mitchell, Monica J.

    2014-01-01

    A Photovoice pilot was conducted with a sample of youth living with sickle cell disease (SCD), in order to further understand their lived experience and examine the acceptability, feasibility, and utility of this method for use in this population. SCD is an inherited genetic condition whose primary symptom is severe pain. Youth were able to reflect on their experiences with SCD using Photovoice and the adapted SHOWeD method. Parents and youth found Photovoice to be valuable for children and adolescents with SCD. Emerging themes included the impact of SCD, coping with the disease, and the importance of family and support. PMID:23455680

  9. Estimate of the soil water retention curve from the sorptivity and β parameter calculated from an upward infiltration experiment

    NASA Astrophysics Data System (ADS)

    Moret-Fernández, D.; Latorre, B.

    2017-01-01

    The water retention curve (θ(h)), which defines the relationship between the volumetric water content (θ) and the matric potential (h), is of paramount importance to characterize the hydraulic behaviour of soils. Because current methods to estimate θ(h) are, in general, tedious and time consuming, alternative procedures to determine θ(h) are needed. Using an upward infiltration curve, the main objective of this work is to present a method to determine the parameters of the van Genuchten (1980) water retention curve (α and n) from the sorptivity (S) and the β parameter defined in the 1D infiltration equation proposed by Haverkamp et al. (1994). The first specific objective is to present an equation, based on the Haverkamp et al. (1994) analysis, which allows describing an upward infiltration process. Secondary, assuming a known saturated hydraulic conductivity, Ks, calculated on a finite soil column by the Darcy's law, a numerical procedure to calculate S and β by the inverse analysis of an exfiltration curve is presented. Finally, the α and n values are numerically calculated from Ks, S and β. To accomplish the first specific objective, cumulative upward infiltration curves simulated with HYDRUS-1D for sand, loam, silt and clay soils were compared to those calculated with the proposed equation, after applying the corresponding β and S calculated from the theoretical Ks, α and n. The same curves were used to: (i) study the influence of the exfiltration time on S and β estimations, (ii) evaluate the limits of the inverse analysis, and (iii) validate the feasibility of the method to estimate α and n. Next, the θ(h) parameters estimated with the numerical method on experimental soils were compared to those obtained with pressure cells. The results showed that the upward infiltration curve could be correctly described by the modified Haverkamp et al. (1994) equation. While S was only affected by early-time exfiltration data, the β parameter had a

  10. Understanding the experience of stroke: a mixed-method research agenda.

    PubMed

    Clarke, Philippa

    2009-06-01

    The use of both quantitative and qualitative strategies to examine a single research question has been a subject of considerable controversy and still remains a largely uncommon practice in the sociology of health and illness. Yet, when seeking to understand the meaning of a chronic disabling condition in later life from a social psychological perspective, a mixed-method approach is likely to provide the most comprehensive picture. This article provides an overview of the usefulness and appropriateness of a mixed-method approach to understanding the stroke experience. I comment on the current state of research on the experience of stroke, including epistemological and ontological orientations. Using real data examples, I address paradigmatic assumptions, methods of integration, as well as challenges and pitfalls in integrating methods. I conclude by considering future directions in this field of research.

  11. Understanding the Experience of Stroke: A Mixed-Method Research Agenda

    PubMed Central

    Clarke, Philippa

    2009-01-01

    The use of both quantitative and qualitative strategies to examine a single research question has been a subject of considerable controversy and still remains a largely uncommon practice in the sociology of health and illness. Yet, when seeking to understand the meaning of a chronic disabling condition in later life from a social psychological perspective, a mixed-method approach is likely to provide the most comprehensive picture. This article provides an overview of the usefulness and appropriateness of a mixed-method approach to understanding the stroke experience. I comment on the current state of research on the experience of stroke, including epistemological and ontological orientations. Using real data examples, I address paradigmatic assumptions, methods of integration, as well as challenges and pitfalls in integrating methods. I conclude by considering future directions in this field of research. PMID:19386828

  12. The solar activity measurements experiments (SAMEX) for improved scientific understanding of solar activity

    NASA Technical Reports Server (NTRS)

    1989-01-01

    The Solar Activity Measurements Experiments (SAMEX) mission is described. It is designed to provide a look at the interactions of magnetic fields and plasmas that create flares and other explosive events on the sun in an effort to understand solar activity and the nature of the solar magnetic field. The need for this mission, the instruments to be used, and the expected benefits of SAMEX are discussed.

  13. Understanding Creep Mechanisms in Graphite with Experiments, Multiscale Simulations, and Modeling

    SciTech Connect

    Eapen, Jacob; Murty, Korukonda; Burchell, Timothy

    2014-06-02

    Disordering mechanisms in graphite have a long history with conflicting viewpoints. Using Raman and x-ray photon spectroscopy, electron microscopy, x-ray diffraction experiments and atomistic modeling and simulations, the current project has developed a fundamental understanding of early-to-late state radiation damage mechanisms in nuclear reactor grade graphite (NBG-18 and PCEA). We show that the topological defects in graphite play an important role under neutron and ion irradiation.

  14. The Experience of Addiction as Told by the Addicted: Incorporating Biological Understandings into Self-Story

    PubMed Central

    Hammer, Rachel R; Dingel, Molly J; Ostergren, Jenny E; Nowakowski, Katherine E; Koenig, Barbara A

    2012-01-01

    How do the addicted view addiction against the framework of formal theories that attempt to explain the condition? In this empirical paper, we report on the lived experience of addiction based on 63 semi-structured, open-ended interviews with individuals in treatment for alcohol and nicotine abuse at five sites in Minnesota. Using qualitative analysis, we identified four themes that provide insights into understanding how people who are addicted view their addiction, with particular emphasis on the biological model. More than half of our sample articulated a biological understanding of addiction as a disease. Themes did not cluster by addictive substance used; however, biological understandings of addiction did cluster by treatment center. Biological understandings have the potential to become dominant narratives of addiction in the current era. Though the desire for a “unified theory” of addiction seems curiously seductive to scholars, it lacks utility. Conceptual “disarray” may actually reflect a more accurate representation of the illness as told by those who live with it. For practitioners in the field of addiction, we suggest the practice of narrative medicine with its ethic of negative capability as a useful approach for interpreting and relating to diverse experiences of disease and illness. PMID:23081782

  15. The Effect of Swimming Experience on Acquisition and Retention of Swimming-Based Taste Aversion Learning in Rats

    ERIC Educational Resources Information Center

    Masaki, Takahisa; Nakajima, Sadahiko

    2010-01-01

    Swimming endows rats with an aversion to a taste solution consumed before swimming. The present study explored whether the experience of swimming before or after the taste-swimming trials interferes with swimming-based taste aversion learning. Experiment 1 demonstrated that a single preexposure to 20 min of swimming was as effective as four or…

  16. An appetitive experience after fear memory destabilization attenuates fear retention: involvement GluN2B-NMDA receptors in the Basolateral Amygdala Complex.

    PubMed

    Ferrer Monti, Roque I; Giachero, Marcelo; Alfei, Joaquín M; Bueno, Adrián M; Cuadra, Gabriel; Molina, Victor A

    2016-09-01

    It is known that a consolidated memory can return to a labile state and become transiently malleable following reactivation. This instability is followed by a restabilization phase termed reconsolidation. In this work, we explored whether an unrelated appetitive experience (voluntary consumption of diluted sucrose) can affect a contextual fear memory in rats during the reactivation-induced destabilization phase. Our findings show that exposure to an appetitive experience following reactivation can diminish fear retention. This effect persisted after 1 wk. Importantly, it was achieved only under conditions that induced fear memory destabilization. This result could not be explained as a potentiated extinction, because sucrose was unable to promote extinction. Since GluN2B-containing NMDA receptors in the basolateral amygdala complex (BLA) have been implicated in triggering fear memory destabilization, we decided to block pharmacologically these receptors to explore the neurobiological bases of the observed effect. Intra-BLA infusion with ifenprodil, a GluN2B-NMDA antagonist, prevented the fear reduction caused by the appetitive experience. In sum, these results suggest that the expression of a fear memory can be dampened by an unrelated appetitive experience, as long as memory destabilization is achieved during reactivation. Possible mechanisms behind this effect and its clinical implications are discussed.

  17. Stratospheric controlled perturbation experiment: a small-scale experiment to improve understanding of the risks of solar geoengineering.

    PubMed

    Dykema, John A; Keith, David W; Anderson, James G; Weisenstein, Debra

    2014-12-28

    Although solar radiation management (SRM) through stratospheric aerosol methods has the potential to mitigate impacts of climate change, our current knowledge of stratospheric processes suggests that these methods may entail significant risks. In addition to the risks associated with current knowledge, the possibility of 'unknown unknowns' exists that could significantly alter the risk assessment relative to our current understanding. While laboratory experimentation can improve the current state of knowledge and atmospheric models can assess large-scale climate response, they cannot capture possible unknown chemistry or represent the full range of interactive atmospheric chemical physics. Small-scale, in situ experimentation under well-regulated circumstances can begin to remove some of these uncertainties. This experiment-provisionally titled the stratospheric controlled perturbation experiment-is under development and will only proceed with transparent and predominantly governmental funding and independent risk assessment. We describe the scientific and technical foundation for performing, under external oversight, small-scale experiments to quantify the risks posed by SRM to activation of halogen species and subsequent erosion of stratospheric ozone. The paper's scope includes selection of the measurement platform, relevant aspects of stratospheric meteorology, operational considerations and instrument design and engineering.

  18. `I'd rather go and know': women's understanding and experience of DEXA scanning for osteoporosis

    PubMed Central

    Richardson, Jane C.; Hassell, Andrew B.; Hay, Elaine M.; Thomas, Elaine

    2002-01-01

    Objective  To explore women's knowledge and understanding of osteoporosis and of dual energy x‐ray absorptiometer (DEXA) scans; the factors influencing their decision to have a scan and their experience of undergoing a DEXA scan. Design  In‐depth interviews (using a topic guide) were carried out with 12 women [before a DEXA scan and after they had discussed the results with their general practitioner (GP)] and with three women who chose not to have a scan. Setting  Stoke‐on‐Trent, Staffordshire, UK. Participants  Women who responded to a primary‐care based questionnaire were purposively selected for interview. Results  The women interviewed had varied levels of understanding of osteoporosis. For the majority of participants the scan was an overwhelmingly positive experience, despite some women's negative expectations. Findings are also explored in terms of the influences on women's decision‐making about whether to have a scan and the concept of `knowing' one's risk status. Conclusions  The main implication for primary care is how to improve women's understanding of osteoporosis and DEXA scans in order to promote the strategy of scanning high‐risk women. PMID:12031052

  19. Infants' social and motor experience and the emerging understanding of intentional actions.

    PubMed

    Brandone, Amanda C

    2015-04-01

    During the first year of life, infants possess some of the key social-cognitive abilities required for success in a social world: Infants interpret others' actions in terms of their intentions and can use this understanding prospectively to generate predictions about others' behavior. Exactly how these foundational abilities develop is currently unknown. The goal of this study was to shed light on the developmental mechanisms underlying changes in infants' understanding of intentional actions by documenting relations between infants' intention understanding and other emerging social (joint attention) and motor (means-end and self-locomotion) abilities. Using eye tracking, 8- to 11-month-olds infants' (N = 80) ability to visually predict the goal of an ongoing successful or failed intentional action was examined in relation to their developing means-end, self-locomotion, and joint attention abilities. Results confirmed previous findings showing improvements in infants' ability to interpret and make predictions about others' failed intentional actions. Importantly, results also indicated that parent-report measures of infants' initiating-joint-attention and self-locomotion abilities were associated with the ability to visually predict the outcome of a failed reaching action. These data support the view that infants' social and motor experiences may contribute to changes in their social-cognitive abilities. In particular, joint-attentive social interactions that occur with increasing frequency as infants learn to crawl and walk may shape infants' understanding of others as intentional agents.

  20. Anguish, Yearning, and Identity: Toward a Better Understanding of the Pregnant Hispanic Woman's Prenatal Care Experience.

    PubMed

    Fitzgerald, Elizabeth Moran; Cronin, Sherill Nones; Boccella, Sarah Hess

    2016-09-01

    The purpose of this phenomenological study was to seek a better understanding of needs and access issues among pregnant, low-income Hispanic women. Hispanic women who attended a community prenatal education program participated in follow-up focus groups to explore their experiences regarding prenatal education, pregnancy resources, access to, and satisfaction with, the care available to them. Focus groups were facilitated by a leader, bilingual in English and Spanish, with knowledge of the Hispanic culture. Sessions were audiotaped, then translated into English for transcription. Data were analyzed according to guidelines by Colaizzi and three themes emerged: pregnant Hispanic women experienced a sense of anguish (la angustia) from questions and unknowns rampant during pregnancy, leading to a yearning (el anhelo) to learn and understand more, but with a desire to do so without sacrificing native identity (la identidad). Implications of these themes for improving prenatal care for this population are explored.

  1. Revealing moments: formulating understandings of adverse experiences in a health appraisal interview.

    PubMed

    Beach, W A; Dixson, C N

    2001-01-01

    Analysis of a health appraisal interview reveals how an interviewer employs formulations to organize talk about a patient's medical history. When selected reportings by patient are paraphrased, a three-part formulations cycle is initiated: (1) interviewer's formulated understandings, (2) patient's confirmation, and (3) topic shift by interviewer. The reenactment of this interactional pattern promotes increasing attention to patient's adverse experiences as "root problems" underlying adult health status (e.g. molestation, obesity, depression). Creating an environment for patient's emergent disclosures is facilitated by displaying non-judgmental sensitivity to patient's stated concerns, soliciting alignment to particular reconstructions and avoidance of moving the interview forward prematurely and to issues not grounded in patient's illness circumstances. The identification and utilization of communication techniques for attending to patient's bio-psycho-social history is critical for refining understandings of empathic interviewing, enhancing diagnosis and treatment (e.g. referrals), decreasing patients' utilization of health care systems, and ultimately reducing costs for quality medical care.

  2. The Struggle to Understand: Exploring Medical Students' Experiences of Learning and Understanding during a Basic Science Course

    ERIC Educational Resources Information Center

    Weurlander, Maria; Scheja, Max; Hult, Håkan; Wernerson, Annika

    2016-01-01

    The aim of the research reported in this paper was to explore students' "journey" towards conceptual understanding during an undergraduate course. The task that medical students face--to learn a substantial quantity of detailed knowledge and integrate into a coherent whole in a limited time frame--is demanding. Seven students were…

  3. Demonstrating Understanding, a Whole Body Experience? Can Year One Children Show Their Science Understanding through the Use of Gestures?

    ERIC Educational Resources Information Center

    Davis, Anthony

    2016-01-01

    This research project uses the methods of Crowder and Callinan and Sharp to assess year one children's (age 5-6) personal understanding of scientific concepts. This research project uses video recording as a primary resource of data collection within a case study approach using a participant observer method. Analysis supports the work of Crowder…

  4. Understanding the Effects of Collisional Evolution and Spacecraft Impact Experiments on Comets and Asteroids

    NASA Technical Reports Server (NTRS)

    Lederer, S.M.; Jensen, E.A.; Fane, M.; Smith, D.C.; Holmes, J.; Keller, L.P.; Lindsay, S.S.; Wooden, D.H.; Whizin, A.; Cintala, M.J.; Zolensky, M.E.

    2017-01-01

    Comets and asteroids have endured impacts from other solar system bodies that result in outcomes ranging from catastrophic collisions to regolith evolution due to micrometeorid bombardment of the surface ices and refactory components. Experiments designed to better understand these relics of solar system formation have been conducted on Earth in a laboratory setting, as well as in space through, e.g., the Deep Impact Mission to Comet Tempel 1. Deep Impact fired a high-speed impactor into the roughly 6 km nucleus of the comet. The ejecta plume generated by the impact was studied by both spacecraft instrumentation and groundbased telescopes.

  5. Using LGI experiments to achieve better understanding of pedestal-edge coupling in NSTX-U

    SciTech Connect

    Wang, Zhehui

    2015-02-23

    PowerPoint presentation. Latest advances in granule or dust injection technologies, fast and high-resolution imaging, together with micro-/nano-structured material fabrication, provide new opportunities to examine plasma-material interaction (PMI) in magnetic fusion environment. Some of our previous work in these areas is summarized. The upcoming LGI experiments in NSTX-U will shed new light on granular matter transport in the pedestal-edge region. In addition to particle control, these results can also be used for code validation and achieving better understanding of pedestal-edge coupling in fusion plasmas in both NSTX-U and others.

  6. Retention of Nickel in Soils: Sorption-Desorption and Extended X-ray Absorption Fine Structure Experiments

    EPA Science Inventory

    Adsorption and desorption of heavy metals in soils are primary factors that influence their bioavailability and mobility in the soil profile. To examine the characteristics of nickel (Ni) adsorption-desorption in soils, kinetic batch experiments were carried out followed by Ni re...

  7. A Comparison of the First-Year Experience Programming to Enhance the Retention of Future Allied Health Professionals

    ERIC Educational Resources Information Center

    Whalen, Tina Forsythe

    2012-01-01

    This mixed-methods case study examined the effectiveness of a new first-year experience (FYE) curriculum for selected Choose Ohio First Scholars in the College of Allied Health Sciences (CAHS) and compared it with the effectiveness of the traditional FYE curriculum in CAHS. The quantitative phase of the study involved the collection and analysis…

  8. A threat to the understanding of oneself: Intensive care patients' experiences of dependency

    PubMed Central

    Lykkegaard, Kristina; Delmar, Charlotte

    2013-01-01

    This study examines the meaning of dependency on care as experienced by intensive care patients. Literature on the subject is sparse, but research from nonintensive settings shows that dependency is often experienced negatively. The study is based on in-depth qualitative semistructured interviews with three former patients characterized as narratives. The analysis is inspired by a phenomenological hermeneutical method. The study has found that dependency is experienced as difficult and that the experience seems to be attached to the relationship to oneself. Patients feel powerless and experience shame, their understanding of self is threatened, and they fight for independence in the course after intensive care. The findings might be influenced by the study being conducted in a Western country setting, where independence is valued. They can be used as means of reflection on nursing practice and matters such as communication and patient participation. PMID:23809023

  9. Understanding (Galactic) Foreground Emission: A Road To Success For The LOFAR-EoR Experiment

    NASA Astrophysics Data System (ADS)

    Jelic, Vibor; Lofar Eor Team

    2014-04-01

    The LOFAR-EoR experiment will use the innovative technology and capabilities of the radio telescope LOFAR to study the Epoch of Reionization (EoR). However, feeble cosmological radiation is swamped by the prominent foreground emission of our Galaxy and other extragalactic radio sources. This emission is two to three orders of magnitude stronger than the EoR signal. Without understanding and removing the foreground emission from the data, we will not be able to detect the cosmological radiation and probe the EoR. During my talk I will give an overview of the LOFAR-EoR experiment, its challenges, and present the most recent observational results in particular detection of peculiar structures in poalrization.

  10. A Monte Carlo Simulation for Understanding Energy Measurements of Beta Particles Detected by the UCNb Experiment

    NASA Astrophysics Data System (ADS)

    Feng, Chi; UCNb Collaboration

    2011-10-01

    It is theorized that contributions to the Fierz interference term from scalar interaction beyond the Standard Model could be detectable in the spectrum of neutron beta-decay. The UCNb experiment run at the Los Alamos Neutron Science Center aims to accurately measure the neutron beta-decay energy spectrum to detect a nonzero interference term. The instrument consists of a cubic ``integrating sphere'' calorimeter attached with up to 4 photomultiplier tubes. The inside of the calorimeter is coated with white paint and a thin UV scintillating layer made of deuterated polystyrene to contain the ultracold neutrons. A Monte Carlo simulation using the Geant4 toolkit is developed in order to provide an accurate method of energy reconstruction. Offline calibration with the Kellogg Radiation Laboratory 140 keV electron gun and conversion electron sources will be used to validate the Monte Carlo simulation to give confidence in the energy reconstruction methods and to better understand systematics in the experiment data.

  11. A threat to the understanding of oneself: intensive care patients' experiences of dependency.

    PubMed

    Lykkegaard, Kristina; Delmar, Charlotte

    2013-06-28

    This study examines the meaning of dependency on care as experienced by intensive care patients. Literature on the subject is sparse, but research from nonintensive settings shows that dependency is often experienced negatively. The study is based on in-depth qualitative semistructured interviews with three former patients characterized as narratives. The analysis is inspired by a phenomenological hermeneutical method. The study has found that dependency is experienced as difficult and that the experience seems to be attached to the relationship to oneself. Patients feel powerless and experience shame, their understanding of self is threatened, and they fight for independence in the course after intensive care. The findings might be influenced by the study being conducted in a Western country setting, where independence is valued. They can be used as means of reflection on nursing practice and matters such as communication and patient participation.

  12. Primary healthcare NZ nurses' experiences of advance directives: understanding their potential role.

    PubMed

    Davidson, Raewyn; Banister, Elizabeth; de Vries, Kay

    2013-07-01

    Advance directives are one aspect of advance care planning designed to improve end of life care. The New Zealand Nurses Organisation released their first mission statement in 2010 concerning advance directives suggesting an increase in the use of these. A burgeoning older population, expected to rise over the next few years, places the primary healthcare nurse in a pivotal role to address the challenges in constructing advance directives. While literature supports the role for primary healthcare nurses in promoting advance directives, no research was found on this role in the New Zealand context. This paper presents results of a qualitative study conducted in New Zealand with 13 senior primary healthcare nurses with respect to their knowledge, attitudes, and experiences of advance directives. Results of the analysis revealed a dynamic process involving participants coming to understand their potential role in this area. This process included reflection on personal experience with advance directives; values and ethics related to end of life issues; and professional actions.

  13. A Case Study of Understanding the Influence of Cultural Patterns on International Students' Perception and Experience with Online Learning

    ERIC Educational Resources Information Center

    Paralejas, Cynthia G.

    2013-01-01

    This dissertation aimed to understand the influence of cultural patterns on international students' perception and experience with online learning. This case study utilized Hofstede's cultural dimension model as an interpretative framework to understand what are the international students' perceptions and experiences with online courses. Two…

  14. The Voluntariat: A Frieirean framework to understand the nature of undergraduate international (medical) experiences

    PubMed Central

    Qaiser, Seemi; Dimaras, Helen; Hamel, Paul

    2016-01-01

    Despite literature documenting limited and asymmetrical benefits along with ethical issues, short-term international volunteering is increasingly popular among North American university students as a perceived advantage when applying to professional healthcare schools or the job market. Academic institutions are also encouraging students to pursue international experiences in order to cultivate values as global citizens. These experiences are most typically limited to economically privileged students. Furthermore, international activities in developing countries often lack a pedagogy of social justice and may confirm a simplistic understanding of development. Brazilian educator Paulo Freire’s “liberation pedagogy” provides a framework for understanding the limitations of international volunteering, whereby the presence of privileged volunteers implementing Western models of development may hinder aspects of local movements. Regardless, university students face intense competition in accessing opportunities, such as medical school, and pay large sums to participate in volunteering to strengthen their academic credentials. We propose that these students form “the voluntariat.” They simultaneously play two roles by, first, contributing to the conditions that oppress the very communities in which they volunteer and, second, by playing a role as objects of oppression by the liberal institutions of learning and employment to which they are attempting to gain access. PMID:28344706

  15. Classroom virtual lab experiments as teaching tools for explaining how we understand planetary processes

    NASA Astrophysics Data System (ADS)

    Hill, C. N.; Schools, H.; Research Team Members

    2012-12-01

    This presentation will report on a classroom pilot study in which we teamed with school teachers in four middle school classes to develop and deploy course modules that connect the real-world to virtual forms of laboratory experiments.The broad goal is to help students realize that seemingly complex Earth system processes can be connected to basic properties of the planet and that this can be illustrated through idealized experiment. Specifically the presentation will describe virtual modules based on on-demand cloud computing technologies that allow students to test the notion that pole equator gradients in radiative forcing together with rotation can explain characteristic patterns of flow in the atmosphere. The module developed aligns with new Massachusetts science standard requirements regarding understanding of weather and climate processes. These new standards emphasize an appreciation of differential solar heating and a qualitative understanding of the significance of rotation. In our preliminary classroom pilot studies we employed pre and post evaluation tests to establish that the modules had increased student knowledge of phenomenology and terms. We will describe the results of these tests as well as results from anecdotal measures of student response. This pilot study suggests that one way to help make Earth science concepts more tractable to a wider audience is through virtual experiments that distill phenomena down, but still retain enough detail that students can see the connection to the real world. Modern computer technology and developments in research models appear to provide an opportunity for more work in this area. We will describe some follow-up possibilities that we envisage.

  16. New Teacher Retention in a Suburban School District: A Study of New Teachers' Perceptions of Their First-Year Experiences and Their Reasons for Remaining with the School System

    ERIC Educational Resources Information Center

    Phillip, Monique W.

    2013-01-01

    The purpose of this correlational study was to determine if there was a significant discrimination between New Teachers' perceptions of yearlong experiences and their reasons for remaining. This study relied on secondary data from one mid-Atlantic school system that has enjoyed higher teacher retention rates than the national average. In this…

  17. A mixed-method approach to understanding the experiences of non-deployed military caregivers.

    PubMed

    Lara-Cinisomo, Sandraluz; Chandra, Anita; Burns, Rachel M; Jaycox, Lisa H; Tanielian, Terri; Ruder, Teague; Han, Bing

    2012-02-01

    Given the unprecedented operational tempo of the Afghanistan and Iraq wars and the heavy involvement of the Reserve and National Guard, the stress that military families are exposed to is distinct from stress in earlier conflicts, with little empirical data to inform the impact on non-deployed military caregivers or "home caregivers." The study seeks to examine the experiences of home caregivers during deployments, with a focus on the impact of deployment on the caregiver's well-being. We conducted 50 qualitative interviews and 1,337 survey interviews with home caregivers who experienced at least one deployment. The structured qualitative interview focused on caregiver experiences during deployment. The quantitative data centered on caregiver well-being and household and relationship hassles. The qualitative interview notes were the unit of analysis and traditional methods were used to analyze the data. The quantitative data were analyzed using regression models. The qualitative data revealed key deployment-related household challenges that caregivers experience and the effect of those challenges on caregivers. Multivariate analyses of the quantitative data explored differences in caregivers' emotional well-being, household and relationship hassles. The results showed important component and deployment experience differences. Caregivers affiliated with the National Guard and those with more months of deployment reported significantly poorer emotional well-being, and more household and relationship hassles. Given the important role that maternal well-being has on child and family functioning, it is critical to understand how the stress of deployment is affecting mothers in their daily routines, especially during potentially high stress periods.

  18. Managing retention.

    PubMed

    Carter, Tony

    2007-01-01

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

  19. Stratospheric controlled perturbation experiment: a small-scale experiment to improve understanding of the risks of solar geoengineering

    PubMed Central

    Dykema, John A.; Keith, David W.; Anderson, James G.; Weisenstein, Debra

    2014-01-01

    Although solar radiation management (SRM) through stratospheric aerosol methods has the potential to mitigate impacts of climate change, our current knowledge of stratospheric processes suggests that these methods may entail significant risks. In addition to the risks associated with current knowledge, the possibility of ‘unknown unknowns’ exists that could significantly alter the risk assessment relative to our current understanding. While laboratory experimentation can improve the current state of knowledge and atmospheric models can assess large-scale climate response, they cannot capture possible unknown chemistry or represent the full range of interactive atmospheric chemical physics. Small-scale, in situ experimentation under well-regulated circumstances can begin to remove some of these uncertainties. This experiment—provisionally titled the stratospheric controlled perturbation experiment—is under development and will only proceed with transparent and predominantly governmental funding and independent risk assessment. We describe the scientific and technical foundation for performing, under external oversight, small-scale experiments to quantify the risks posed by SRM to activation of halogen species and subsequent erosion of stratospheric ozone. The paper's scope includes selection of the measurement platform, relevant aspects of stratospheric meteorology, operational considerations and instrument design and engineering. PMID:25404681

  20. Understanding H isotope adsorption and absorption of Al-alloys using modeling and experiments (LDRD: #165724)

    SciTech Connect

    Ward, Donald K.; Zhou, Xiaowang; Karnesky, Richard A.; Kolasinski, Robert; Foster, Michael E.; Thurmer, Konrad; Chao, Paul; Epperly, Ethan Nicholas; Zimmerman, Jonathan A.; Wong, Bryan M.; Sills, Ryan B.

    2015-09-01

    Current austenitic stainless steel storage reservoirs for hydrogen isotopes (e.g. deuterium and tritium) have performance and operational life-limiting interactions (e.g. embrittlement) with H-isotopes. Aluminum alloys (e.g.AA2219), alternatively, have very low H-isotope solubilities, suggesting high resistance towards aging vulnerabilities. This report summarizes the work performed during the life of the Lab Directed Research and Development in the Nuclear Weapons investment area (165724), and provides invaluable modeling and experimental insights into the interactions of H isotopes with surfaces and bulk AlCu-alloys. The modeling work establishes and builds a multi-scale framework which includes: a density functional theory informed bond-order potential for classical molecular dynamics (MD), and subsequent use of MD simulations to inform defect level dislocation dynamics models. Furthermore, low energy ion scattering and thermal desorption spectroscopy experiments are performed to validate these models and add greater physical understanding to them.

  1. As(V)/Cr(VI) retention on un-amended and waste-amended soil samples: competitive experiments.

    PubMed

    Rivas-Pérez, Ivana M; Conde-Cid, Manuel; Nóvoa-Muñoz, Juan Carlos; Arias-Estévez, Manuel; Fernández-Sanjurjo, María J; Álvarez-Rodríguez, Esperanza; Núñez-Delgado, Avelino

    2017-01-01

    Focusing on simultaneous arsenic and chromium pollution, we used batch-type experiments to study As(V)/Cr (VI) competitive sorption on soil samples, pyritic material, mussel shell, oak ash, pine bark and hemp waste, as well as on binary mixtures (50 % mussel shell and 50 % another material-oak ash, pine bark, or hemp waste), and on forest and vineyard soil samples and pyritic material amended with 48 t ha(-1) of mussel shell, oak ash, pine bark, or hemp waste. Equal As(V) and Cr(VI) concentrations (0 to 6 mmol L(-1)) were added to the individual materials, binary mixtures, and 48 t ha(-1) amended materials. The individual forest soil sample, pyritic material, and oak ash showed clearly higher As(V) sorption, whereas Cr(VI) sorption was higher on pine bark. Sorption was up to 50 % higher for As(V) than for Cr(VI) on the forest soil sample, oak ash, and pyritic material, while pine bark sorbed 95 % more Cr(VI). Regarding binary mixtures, the presence of mussel shell increased As(V) sorption on pine bark and Cr(VI) sorption on hemp waste. As regards the amendments, in the case of the forest soil sample, the amendments with oak ash and mussel shell increased As(V) sorption, while pine bark amendment increased Cr(VI) sorption; in the vineyard soil sample, the mussel shell amendment increased As(V) sorption; in the pyritic material, pine bark amendment increased Cr(VI) sorption. These results could be useful to appropriately manage the soils and individual or mixed by-products assayed when As(V) and Cr(VI) pollution occurs.

  2. Bridging the Gap Between Theory and Experiment to Derive a Detailed Understanding of Hammerhead Ribozyme Catalysis

    PubMed Central

    Lee, Tai-Sung; Wong, Kin-Yiu; Giambasu, George M.; York, Darrin M.

    2016-01-01

    Herein we summarize our progress toward the understanding of hammerhead ribozyme (HHR) catalysis through a multiscale simulation strategy. Simulation results collectively paint a picture of HHR catalysis: HHR first folds to form an electronegative active site pocket to recruit a threshold occupation of cationic charges, either a Mg2+ ion or multiple monovalent cations. Catalytically active conformations that have good in-line fitness are supported by specific metal ion coordination patterns that involve either a bridging Mg2+ ion or multiple Na+ ions, one of which is also in a bridging coordination pattern. In the case of a single Mg2+ ion bound in the active site, the Mg2+ ion undergoes a migration that is coupled with deprotonation of the nucleophile (C17:O2′). As the reaction proceeds, the Mg2+ ion stabilizes the accumulating charge of the leaving group and significantly increases the general acid ability of G8:O2′. Further computational mutagenesis simulations suggest that the disruptions due to mutations may severely impact HHR catalysis at different stages of the reaction. Catalytic mechanisms supported by the simulation results are consistent with available structural and biochemical experiments, and together they advance our understanding of HHR catalysis. PMID:24156941

  3. Pulmonary retention of coal dusts

    SciTech Connect

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

    1980-01-01

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

  4. Combining stochastic models with experiments to understand the dynamics of monarch butterfly colonization.

    PubMed

    Drury, Kevin L S; Dwyer, Greg

    2005-12-01

    Stochastic models are of increasing importance in ecology but are usually only applied to observational data. Here we use a stochastic population model to combine experimental and observational data to understand the colonization of old fields by monarch butterflies Danaus plexippus. We experimentally tested for density dependence in oviposition rates when predators were excluded, and we measured predation rates under natural conditions. Significance tests on the resulting data showed that both oviposition and predation were density dependent but could not show how oviposition and mortality combine to determine egg densities in nature. We therefore used our data to calculate the Akaike Information Criterion to choose between a nested suite of stochastic models that differed in their oviposition and mortality terms. When we simply fit the models to the observational data, the best model assumed density independence in both oviposition and predation. When we instead first estimated the oviposition rate at low density from experimental data, however, the best model included density dependence in oviposition, and a model that included density dependence in both oviposition and predation performed nearly as well. This result is consistent with our experiments and suggests that experiments can enhance the usefulness of stochastic models in ecology.

  5. Understanding the burnout experience: recent research and its implications for psychiatry

    PubMed Central

    Maslach, Christina; Leiter, Michael P.

    2016-01-01

    The experience of burnout has been the focus of much research during the past few decades. Measures have been developed, as have various theoretical models, and research studies from many countries have contributed to a better understanding of the causes and consequences of this occupationally‐specific dysphoria. The majority of this work has focused on human service occupations, and particularly health care. Research on the burnout experience for psychiatrists mirrors much of the broader literature, in terms of both sources and outcomes of burnout. But it has also identified some of the unique stressors that mental health professionals face when they are dealing with especially difficult or violent clients. Current issues of particular relevance for psychiatry include the links between burnout and mental illness, the attempts to redefine burnout as simply exhaustion, and the relative dearth of evaluative research on potential interventions to treat and/or prevent burnout. Given that the treatment goal for burnout is usually to enable people to return to their job, and to be successful in their work, psychiatry could make an important contribution by identifying the treatment strategies that would be most effective in achieving that goal. PMID:27265691

  6. Understanding the burnout experience: recent research and its implications for psychiatry.

    PubMed

    Maslach, Christina; Leiter, Michael P

    2016-06-01

    The experience of burnout has been the focus of much research during the past few decades. Measures have been developed, as have various theoretical models, and research studies from many countries have contributed to a better understanding of the causes and consequences of this occupationally-specific dysphoria. The majority of this work has focused on human service occupations, and particularly health care. Research on the burnout experience for psychiatrists mirrors much of the broader literature, in terms of both sources and outcomes of burnout. But it has also identified some of the unique stressors that mental health professionals face when they are dealing with especially difficult or violent clients. Current issues of particular relevance for psychiatry include the links between burnout and mental illness, the attempts to redefine burnout as simply exhaustion, and the relative dearth of evaluative research on potential interventions to treat and/or prevent burnout. Given that the treatment goal for burnout is usually to enable people to return to their job, and to be successful in their work, psychiatry could make an important contribution by identifying the treatment strategies that would be most effective in achieving that goal.

  7. Improved Understanding of Carbon Storage Risk Via Controlled-Release Experiments

    NASA Astrophysics Data System (ADS)

    Birkholzer, J. T.; Guglielmi, Y.; Rutqvist, J.; Zheng, L.; Spycher, N.

    2014-12-01

    Two issues are often recognized as main risk drivers for carbon storage projects. The first is the possibility of pressure-induced slip of pre-existing faults, which can lead to breaching of seals to CO2 storage reservoirs. Although the mechanics of induced seismicity are well known, the characteristics of such slip events are poorly constrained and significant questions remain. The second is the potential impact of leaking CO2 on the quality of shallow potable groundwater. While several studies have been conducted using laboratory tests, natural analogues, and numerical models to evaluate the water quality changes induced by elevated CO2 concentrations, predictive understanding of these coupled processes remains limited in realistic field settings. We discuss in this invited contribution two controlled-release field experiments targeting remaining science gaps associated with induced seismicity and groundwater chemistry. The first experiment is a planned active fault slip experiment conducted in an underground research laboratory (URL) in a hardened shale formation that serves as a caprock analog. The critically stressed fault will be perturbed by the injection of fluid under pressure to simulate the influence of CO2 overpressure. The in situ reactivation experiment will use a novel borehole deformation tool that assesses the magnitude of overpressure required to cause slip, defines the mode of this slip as creeping (aseismic) or rapid (seismic), and measures the evolution of permeability on the fault. The second controlled-release field experiment was conducted in 2011/2012 to simulate the release of CO2 from a geologic storage site and study the transport as well as the chemical mechanisms leading to the CO2-induced mobilization of trace elements in a shallow aquifer. The field test involved a dipole system in which the shallow groundwater was pumped from one well, saturated with CO2 at the pressure corresponding to the hydraulic pressure of the aquifer, and

  8. Using Teleducation and Field Experiences to further the Understanding of Coastal Environments

    NASA Astrophysics Data System (ADS)

    Macko, S. A.; Szuba, T. A.; Shugart, H.

    2007-05-01

    This project is an outreach and education program with a partner in the K-12 schools at Accomack County on the Eastern Shore of Virginia. It endeavors to build a community knowledgeable of the importance the ocean plays daily in our lives, and our own impact on the ocean. It is an program built in stages that: 1) Establish high speed live interactive classes (teleducation) linkages with the Eastern Shore High Schools with earth science teachers enabling them to remotely participate in University of Virginia classes in Oceanography (designed on a faculty development basis or acquire NSTA certification in Earth Science Education, as well as participation by seniors in the Accomack Schools; 2) Establish field experiences for teachers and selected students that involve travel to both the Virginia Coast Reserve Long Term Ecological Research (VCR/LTER) Center, UVA to observe first- hand the science programs at those locations and participate in cutting edge coastal marine research efforts. These experiences improve student understanding of the ocean-atmosphere biogeophysical system and encourage students to explore the sciences as a field of study and possible vocation. Advanced high school students and science teachers from Accomack County Public Schools participated in an experience involving field and laboratory methods employed in a NSF-sponsored study of the coupled natural-human dynamics on the Eastern Shore of Virginia over the past 500 years (NSF-Biocomplexity). Students and teachers worked with researchers of the VCR facility in Oyster, VA, collected sediment cores from Chesapeake Bay tributaries, and traveled to the Organic Geochemistry Laboratory at UVA, in Charlottesville, VA to prepare and analyze samples for isotopic and palynological information. In a first of its kind connectivity, in June/July, 2006, using high speed internet connections, a summer class in Oceanography was live, interactively broadcast (teleducation) from UVA to Arcadia High School on

  9. Understanding and improving lithium ion batteries through mathematical modeling and experiments

    NASA Astrophysics Data System (ADS)

    Deshpande, Rutooj D.

    -mechanical degradation of electrode materials to understand the capacity fading of the battery with cycling. With the understanding of chemical and mechanical degradation, we develop a simple phenomenological model to predict battery life. On the experimental part we come up with a novel concept of using liquid metal alloy as a self-healing battery electrode. We develop a method to prepare thin film liquid gallium electrode on a conductive substrate. This enabled us to perform a series of electrochemical and characterization experiments which certify that liquid electrode undergo liquid-solid-liquid transition and thus self-heals the cracks formed during de-insertion. Thus the mechanical degradation can be avoided. We also perform ab-initio calculations to understand the equilibrium potential of various lithium-gallium phases. KEYWORDS: Lithium ion batteries, diffusion induced stresses, self-healing electrode, coupled chemical and mechanical degradation, life-prediction model.

  10. White Students' Understanding of Race: An Exploration of How White University Students, Raised in a Predominately White State, Experience Whiteness

    ERIC Educational Resources Information Center

    Smith, Barbara A.

    2014-01-01

    This study examines White university students' understanding of race. Based in the scholarship on higher education and diversity, and framed in Critical Race Theory (CRT), this study explores the racial awareness of White students. This study contributes to the literature on the racial experience of Whites and an understanding of how White…

  11. Long-term experiments to better understand soil-human interactions

    NASA Astrophysics Data System (ADS)

    Bormann, B. T.; Homann, P. S.

    2011-12-01

    Interactions between soils and people may be transforming global conditions, but the interactions are poorly understood. Changes in soils have proven difficult to quantify, especially in complex ecosystems manifesting large spatiotemporal variability. Long-term ecosystem experiments that evaluate soil change and demonstrate alternative choices are important to understanding changes, discovering new controls and drivers, and influencing decisions. Inspired by agriculture studies, like Rothamsted, the US Forest Service established in 1990 a network of operational-scale experiments across the Pacific Northwest to evaluate long-term effects of different forest management and disturbance regimes. With a strong experimental design, these experiments are now helping to better understand the long-term effects of managing tree harvesting (clearcutting and thinning), woody debris, and tree and understory species composition, and-serendipitously-the effects of fire. Initial results from the Southern Oregon experimental site indicate surprisingly rapid soil changes in some regimes but not others. We've also learned that rapid change presents challenges to repeat sampling. We present our sample-archive and comparable-layer approaches that seek to accommodate changes in surface elevation, aggregation and disaggregation, and mineral-soil exports. Thinning mature forest stands (80-100 yrs old) did not significantly change soil C in 11-yrs. A small upper-layer C increase was observed after thinning, but it was similar to the control. Significant increases in upper-layer soil N were observed with most treatments, but all increases were similar to the control. Leaving woody debris had little effect. The most remarkable change occurred when mature stands were clearcut and Douglas-firs were planted and tended. Associated with rapid growth of Douglas-fir, an average of 8 Mg C ha-1 was lost from weathered soil 4-18 cm deep. This contrasts with clearcuts where early-seral hardwoods and

  12. Strategies for Teacher Retention.

    ERIC Educational Resources Information Center

    Gonzalez, Patricia

    1995-01-01

    Strategies for teacher retention are presented, including successful approaches and elements for operating a state system for personnel recruitment and retention in special education. Such initiatives as the Utah Mentor Teacher Academy; the Texas Teacher Recruitment, Retention and Assistance Program; and the Kansas Recruitment/Retention Project…

  13. Through the eyes of professional developers: Understanding the design of learning experiences for science teachers

    NASA Astrophysics Data System (ADS)

    Higgins, Tara Eileen

    Professional development is important for improving teacher practice and student learning, particularly in inquiry-oriented and technology-enhanced science instruction. This study examines professional developers' practices and their impact on teachers' classroom instruction and student achievement. It analyzes professional developers designing and implementing a five-year professional development program designed to support middle school science teachers. The professional developers are four university-based researchers who worked with sixteen science teachers over three years, setting program goals, facilitating workshops, providing in-classroom support for teachers, and continually refining the program. The analysis is guided by the knowledge integration perspective, a sociocognitive framework for understanding how teachers and professional developers integrate their ideas about teaching and learning. The study investigates the professional developers' goals and teachers' interpretations of those goals. It documents how professional developers plan teacher learning experiences and explores the connection between professional development activities and teachers' classroom practice. Results are based on two rounds of interviews with professional developers, audio recordings of professional developers' planning meetings and videotaped professional development activities. Data include classroom observations, teacher interviews, teacher reflections during professional development activities, and results from student assessments. The study shows the benefit of a professional development approach that relies on an integrated cycle of setting goals, understanding teachers' interpretations, and refining implementation. The professional developers based their design on making inquiry and technology accessible, situating professional development in teachers' work, supporting collaboration, and sustaining learning. The findings reflect alignment of the design goals with the

  14. The Lusi seismic experiment: An initial study to understand the effect of seismic activity to Lusi

    SciTech Connect

    Karyono; Mazzini, Adriano; Sugiharto, Anton; Lupi, Matteo; Syafri, Ildrem; Masturyono,; Rudiyanto, Ariska; Pranata, Bayu; Muzli,; Widodo, Handi Sulistyo; Sudrajat, Ajat

    2015-04-24

    The spectacular Lumpur Sidoarjo (Lusi) eruption started in northeast Java on the 29 of May 2006 following a M6.3 earthquake striking the island [1,2]. Initially, several gas and mud eruption sites appeared along the reactivated strike-slip Watukosek fault system [3] and within weeks several villages were submerged by boiling mud. The most prominent eruption site was named Lusi. The Lusi seismic experiment is a project aims to begin a detailed study of seismicity around the Lusi area. In this initial phase we deploy 30 seismometers strategically distributed in the area around Lusi and along the Watukosek fault zone that stretches between Lusi and the Arjuno Welirang (AW) complex. The purpose of the initial monitoring is to conduct a preliminary seismic campaign aiming to identify the occurrence and the location of local seismic events in east Java particularly beneath Lusi.This network will locate small event that may not be captured by the existing BMKG network. It will be crucial to design the second phase of the seismic experiment that will consist of a local earthquake tomography of the Lusi-AW region and spatial and temporal variations of vp/vs ratios. The goal of this study is to understand how the seismicity occurring along the Sunda subduction zone affects to the behavior of the Lusi eruption. Our study will also provide a large dataset for a qualitative analysis of earthquake triggering studies, earthquake-volcano and earthquake-earthquake interactions. In this study, we will extract Green’s functions from ambient seismic noise data in order to image the shallow subsurface structure beneath LUSI area. The waveform cross-correlation technique will be apply to all of recordings of ambient seismic noise at 30 seismographic stations around the LUSI area. We use the dispersive behaviour of the retrieved Rayleigh waves to infer velocity structures in the shallow subsurface.

  15. The Lusi seismic experiment: An initial study to understand the effect of seismic activity to Lusi

    NASA Astrophysics Data System (ADS)

    Karyono, Mazzini, Adriano; Lupi, Matteo; Syafri, Ildrem; Masturyono, Rudiyanto, Ariska; Pranata, Bayu; Muzli, Widodo, Handi Sulistyo; Sudrajat, Ajat; Sugiharto, Anton

    2015-04-01

    The spectacular Lumpur Sidoarjo (Lusi) eruption started in northeast Java on the 29 of May 2006 following a M6.3 earthquake striking the island [1,2]. Initially, several gas and mud eruption sites appeared along the reactivated strike-slip Watukosek fault system [3] and within weeks several villages were submerged by boiling mud. The most prominent eruption site was named Lusi. The Lusi seismic experiment is a project aims to begin a detailed study of seismicity around the Lusi area. In this initial phase we deploy 30 seismometers strategically distributed in the area around Lusi and along the Watukosek fault zone that stretches between Lusi and the Arjuno Welirang (AW) complex. The purpose of the initial monitoring is to conduct a preliminary seismic campaign aiming to identify the occurrence and the location of local seismic events in east Java particularly beneath Lusi.This network will locate small event that may not be captured by the existing BMKG network. It will be crucial to design the second phase of the seismic experiment that will consist of a local earthquake tomography of the Lusi-AW region and spatial and temporal variations of vp/vs ratios. The goal of this study is to understand how the seismicity occurring along the Sunda subduction zone affects to the behavior of the Lusi eruption. Our study will also provide a large dataset for a qualitative analysis of earthquake triggering studies, earthquake-volcano and earthquake-earthquake interactions. In this study, we will extract Green's functions from ambient seismic noise data in order to image the shallow subsurface structure beneath LUSI area. The waveform cross-correlation technique will be apply to all of recordings of ambient seismic noise at 30 seismographic stations around the LUSI area. We use the dispersive behaviour of the retrieved Rayleigh waves to infer velocity structures in the shallow subsurface.

  16. Understanding the Complexity of the Lived Experiences of Foundation Degree Sport Lecturers within the Context of Further Education

    ERIC Educational Resources Information Center

    Aldous, David

    2014-01-01

    This paper provides an ethnographic account of the lived experiences of Further Education (FE) lecturers (N = 4) who are engaged in the transmission of pedagogic knowledge within a Foundation Degree. To further understand the experiences of the lecturers the paper draws upon Stones' quadripartite cycle of structuration. This conceptual and…

  17. Petmanship: Understanding Elderly Filipinos' Self-Perceived Health and Self-Esteem Captured from Their Lived Experiences with Pet Companions

    ERIC Educational Resources Information Center

    de Guzman, Allan B.; Cucueco, Denise S.; Cuenco, Ian Benedict V.; Cunanan, Nigel Gerome C.; Dabandan, Robel T.; Dacanay, Edgar Joseph E.

    2009-01-01

    Understanding of the lived experiences of geriatric clients with pets, particularly in the Western cultures, has been the subject of many studies. However, little is known about how Asian cultures, particularly the Filipino elderly, view their experiences with their pets in regard to their self-esteem and self-perceived health. This…

  18. Enhancing the Understanding of Marine Ecosystems through Teleducation and Field Experiences

    NASA Astrophysics Data System (ADS)

    Macko, S.

    2006-12-01

    This project is an outreach and education program with a partner in the K-12 schools at Accomack County on the Eastern Shore of Virginia. It endeavors to build a community more knowledgeable of the importance the ocean plays daily in our lives, and our own impact on the ocean. It is an program built in stages that: 1) Establish high speed teleducation linkages with Eastern Shore of Virginia High Schools, for live interactive, classes (teleducation) for earth science teachers enabling them to remotely participate in University of Virginia classes in Oceanography (designed on a faculty development basis or acquire NSTA certification in Earth Science Education, as well as participation by seniors in the Accomack Schools; 2) Establish field experiences for teachers and selected students that involve travel to both the Virginia Coast Reserve Long Term Ecological Research (VCR/LTER) Center, UVA and the NOAA Beaufort, NC Laboratory to observe first- hand the science programs at those locations and participate in cutting edge coastal marine research efforts. These experiences will not only improve student understanding of the ocean-atmosphere biogeophysical system, but also encourage students to explore the sciences as a field of study and possible vocation. Advanced high school students and science teachers from Accomack County Public Schools participated in an experience involving field and laboratory methods employed in a NSF-sponsored study of the coupled natural-human dynamics on the Eastern Shore of Virginia over the past 500 years (NSF-Biocomplexity). Students and teachers worked with researchers of the VCR facility in Oyster, VA, collected sediment cores from Chesapeake Bay tributaries, and traveled to the Organic Geochemistry Laboratory at UVA, in Charlottesville, VA to prepare and analyze samples for isotopic and palynological information. In a first of its kind connectivity, in June/July, 2006, using high speed internet connections, a summer class in

  19. Understanding magnetic nanoparticle osteoblast receptor-mediated endocytosis using experiments and modeling

    NASA Astrophysics Data System (ADS)

    Tran, Nhiem; Webster, Thomas J.

    2013-05-01

    Iron oxide nanoparticles are promising candidates for controlling drug delivery through an external magnetic force to treat a wide range of diseases, including osteoporosis. Previous studies have demonstrated that in the presence of hydroxyapatite coated magnetite (Fe3O4) nanoparticles, osteoblast (or bone forming cell) proliferation and long-term functions (such as calcium deposition) were significantly enhanced. Hydroxyapatite is the major inorganic component of bone. As a further attempt to understand why, in the current study, the uptake of such nanoparticles into osteoblasts was experimentally investigated and mathematically modeled. Magnetite nanoparticles were synthesized using a co-precipitation method and were coated with hydroxyapatite. A cellular uptake experiment at low temperatures indicated that receptor-mediated endocytosis contributed to the internalization of the magnetic nanoparticles into osteoblasts. A model was further developed to explain the uptake of magnetic nanoparticles into osteoblasts using receptor-mediated endocytosis. This model may explain the internalization of hydroxyapatite into osteoblasts to elevate intracellular calcium levels necessary to promote osteoblast functions to treat a wide range of orthopedic problems, including osteoporosis.

  20. Understanding the Learning Assistant experience with Physics Identity and Community of Practice

    NASA Astrophysics Data System (ADS)

    Close, Eleanor; Close, Hunter; Donnelly, David

    2012-10-01

    Learning Assistants (LAs) have been shown to have better conceptual understanding and more favorable beliefs about science than non-LAs, and are more likely to choose a career in K-12 science teaching [1]. We propose that connections between elements of identity, persistence, and participation in an LA program can be explained using the concept of the community of practice and its intimate relationship to identity [2]. In separate work, Hazari et al. found that physics identity was highly correlated to expressed career plans in physics [3]. We hypothesize that a thriving LA program has many features of a well-functioning community of practice and contributes to all four elements of physics identity: personal interest, student performance, competence, and recognition by others. We explore how this analysis of the LA experience might shape decisions and influence outcomes of adoption and adaptations of the LA model.[4pt] [1] Otero, Pollock, & Finkelstein, Am. J. Phys. 78 (11), 1218-1224 (2010).[0pt] [2] Wenger, Communities of Practice: Learning, Meaning, and Identity. (Cambridge Univ. Press, 1998).[0pt] [3] J. Res. Sci. Teach. 47 (8), 978-1003 (2010).

  1. Selenide retention by mackinawite.

    PubMed

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

    2012-09-18

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

  2. A qualitative study of Iranian nurses' understanding and experiences of professional power

    PubMed Central

    Adib Hagbaghery, Mohsen; Salsali, Mahvash; Ahmadi, Fazlollah

    2004-01-01

    Background Nurses are expected to empower their clients, but they cannot do so if they themselves feel powerless. They must become empowered before they can empower others. Some researchers have emphasized that understanding the concept of power is an important prerequisite of any empowerment program. While many authors have tried to define the concept of power, there is no comprehensive definition. This paper is an attempt to clarify the concept of power in nursing. It also would present a model describing the factors affecting nurse empowerment. Methods We chose the grounded-theory approach for analysis of the participants' experiences and their viewpoints regarding the concept of professional power in nursing. Semi-structured interviews and participant observation methods were used to gather the data. Forty-four participants were interviewed and 12 sessions of observation were carried out. The constant comparative analysis method was used. Results Six main themes emerged from the data: "Application of knowledge and skills", "Having authority", "Being self-confident", "Unification and solidarity", "Being supported" and "Organizational culture and structure". According to the participants, nurses' power is influenced by these six variables. A theoretical model was designed to represent the interrelationships between these six variables. Conclusions Nurses' power depends on gaining and applying professional knowledge and skills. Delegating authority and enhancing self-confidence of the nurses also help them to apply their knowledge in practice. Unification of the nurses and their mutual support play the key roles in development of their collective power and provide a base for better working conditions, professional independence and self-regulation. PMID:15217516

  3. Shale Deformation Experiments Toward an Understanding of Elastic and Fracture Anisotropy

    NASA Astrophysics Data System (ADS)

    Kanitpanyacharoen, J.; Miyagi, L. M.; Jugle, M.; Wang, Y.; Yu, T.

    2014-12-01

    The significance of shales as unconventional hydrocarbon reservoirs has opened new research frontiers in geosciences. Among many of its unique physical properties, elastic anisotropy in shales has long been investigated by both experimental and computational approaches. Shales is highly anisotropic due to texture (crystallographic preferred orientation) of their constituent clay minerals. Moreover, texturing is known to cause fracture anisotropy, which can affect both fracture toughness and fracture orientations in metals, ceramics, and polyphase materials. However, the relationship between texture and fracture anisotropy in shale has not been explored. In this study we use the multi-anvil deformation tool (D-DIA) to deform shales with a range of clay and silt contents to failure while collecting x-ray diffraction and radiography images. Diffraction images are used to extract to texture and lattice strain evolution while radiography are used to measure macrostrain and determine failure. Since clay mineral have shear moduli in the range of 6-17 GPa, our stress resolution is in the range of 30 -100 MPa respectively, within the range of unconfined compressive strengths of shales. Our results show that the orientation of clay minerals become more prominent in all samples upon deforming the sample at 100 MPa. Recovered samples are investigated with SEM to document microstructural changes. A second deformation experiment will be coupled with ultrasonic and acoustic emissions measurements to make direct comparisons of elastic anisotropy and understand the role of fracture on anisotropy. Acoustic emissions allows us to locate damage initiation and determine fracture orientations in-situ. This information will be compared with texture data to determine fracture anisotropy in our samples.

  4. Understanding U.S. Healthcare Providers’ Practices and Experiences with Molluscum Contagiosum

    PubMed Central

    Hughes, Christine M.; Damon, Inger K.; Reynolds, Mary G.

    2013-01-01

    Introduction Molluscum contagiosum is a common superficial skin infection caused by the poxvirus, Molluscum Contagiosum virus. The study objective is to obtain a better understanding of physician practices and experiences with molluscum contagiosum in order to focus informational and guidance material. Methods A cross-sectional survey to assess medical practitioners’ knowledge and practices with molluscum contagiosum was conducted using the 2009 DocStyles survey. Questions regarding category and number of molluscum contagiosum patients seen, treatments used and advice given to patients were included in the survey. Results Dermatologists saw the most cases, with the majority seeing 51–100 molluscum contagiosum cases/year. The most common cases seen were children with multiple lesions and adults with genital lesions. Respondents were most likely to recommend treatment to immunocompromised individuals, HIV patients, adults with genital lesions and children with multiple lesions. Cryotherapy was the top choice for all specialties with the exception of OB/GYNs, whose top choice was curettage. “Avoid intimate contact until lesions resolve”, “Avoid touching lesions to reduce further spread”, and “Don’t be concerned, this will go away” were the top advice choices. Discussion Most survey respondents have dealt with molluscum contagiosum in their practice during the previous year. Overall, respondents picked appropriate choices for treatment and advice given; however some ineffective or unnecessary treatments were chosen and recommendations to prevent spread were chosen infrequently. Knowledge gaps for appropriate transmission precaution advice might cause unnecessary spread or autoinoculation. This survey has demonstrated that molluscum contagiosum is a common infection seen by many types of practitioners and therefore guidance on treatment considerations and infection control is valuable. PMID:24155912

  5. Understanding the Experience of Age-Related Vestibular Loss in Older Individuals: A Qualitative Study

    PubMed Central

    Li, Carol; Bridges, John F. P.; Agrawal, Yuri

    2016-01-01

    Background Inner ear balance (or vestibular) function declines with age and is associated with decreased mobility and an increased risk of falls in older individuals. We sought to understand the lived experience of older adults with vestibular loss in order to improve care in this population. Methods Qualitative data were derived from semi-structured interviews of individuals aged 65 years or older presenting to the Balance and Falls Prevention Clinic from February 1, 2014 to March 30, 2015 for evaluation of age-related vestibular loss. Transcripts were analyzed using interpretive phenomenological analysis. We created a taxonomy of overarching superordinate themes based on the World Health Organization's International Classification of Functioning, Disability, and Health (ICF) Framework, and classified key dimensions within each of these themes. Results Sixteen interviews were conducted with individuals (mean age 76.0 years, 75 % female) with age-related vestibular loss. The three superordinate themes and associated key dimensions were (1) body impairment (including depression, fatigue, fear/anxiety, and problems with concentrating and memory); (2) activity limitation and participation restriction (isolation, needing to stop in the middle of activities, reduced participation relative to expectations, reduced ability to drive or travel, and problems with bending/looking up, standing, and walking); and (3) environmental influences (needing help with daily activities). All participants reported difficulty walking. Conclusions Older adults report that vestibular loss impacts their body functioning and restricts their participation in activities. The specific key dimensions uncovered by this qualitative study can be used to evaluate care from the patient's perspective. PMID:26739817

  6. Fuel nozzle tube retention

    DOEpatents

    Cihlar, David William; Melton, Patrick Benedict

    2017-02-28

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

  7. Anisotropic diffusion at the field scale in a 4-year multi-tracer diffusion and retention experiment - I: Insights from the experimental data

    NASA Astrophysics Data System (ADS)

    Gimmi, Thomas; Leupin, Olivier X.; Eikenberg, Jost; Glaus, Martin A.; Van Loon, Luc R.; Waber, H. Niklaus; Wersin, Paul; Wang, Hao A. O.; Grolimund, Daniel; Borca, Camelia N.; Dewonck, Sarah; Wittebroodt, Charles

    2014-01-01

    Claystones are considered worldwide as barrier materials for nuclear waste repositories. In the Mont Terri underground research laboratory (URL), a nearly 4-year diffusion and retention (DR) experiment has been performed in Opalinus Clay. It aimed at (1) obtaining data at larger space and time scales than in laboratory experiments and (2) under relevant in situ conditions with respect to pore water chemistry and mechanical stress, (3) quantifying the anisotropy of in situ diffusion, and (4) exploring possible effects of a borehole-disturbed zone. The experiment included two tracer injection intervals in a borehole perpendicular to bedding, through which traced artificial pore water (APW) was circulated, and a pressure monitoring interval. The APW was spiked with neutral tracers (HTO, HDO, H2O-18), anions (Br, I, SeO4), and cations (Na-22, Ba-133, Sr-85, Cs-137, Co-60, Eu-152, stable Cs, and stable Eu). Most tracers were added at the beginning, some were added at a later stage. The hydraulic pressure in the injection intervals was adjusted according to the measured value in the pressure monitoring interval to ensure transport by diffusion only. Concentration time-series in the APW within the borehole intervals were obtained, as well as 2D concentration distributions in the rock at the end of the experiment after overcoring and subsampling which resulted in ∼250 samples and ∼1300 analyses. As expected, HTO diffused the furthest into the rock, followed by the anions (Br, I, SeO4) and by the cationic sorbing tracers (Na-22, Ba-133, Cs, Cs-137, Co-60, Eu-152). The diffusion of SeO4 was slower than that of Br or I, approximately proportional to the ratio of their diffusion coefficients in water. Ba-133 diffused only into ∼0.1 m during the ∼4 a. Stable Cs, added at a higher concentration than Cs-137, diffused further into the rock than Cs-137, consistent with a non-linear sorption behavior. The rock properties (e.g., water contents) were rather homogeneous at the

  8. Seventh Grade Students' Qualitative Understanding of the Concept of Mass Influenced by Real Experiments and Virtual Experiments

    ERIC Educational Resources Information Center

    Stamenkovski, Sasha; Zajkov, Oliver

    2014-01-01

    This research is conducted among 65 seventh graders (12-14 years old) who attend introductory course on physics. Tests and interviews are used to trace the roots of the students' misconceptions about mass. Results from the research reveal serious weaknesses in students' understanding of concept of mass, and its confusion with concepts of density…

  9. Towards an Understanding of Flow and Other Positive Experience Phenomena within Outdoor and Adventurous Activities.

    ERIC Educational Resources Information Center

    Boniface, Margaret R.

    2000-01-01

    People involved in adventurous activities frequently experience positive phenomena termed peak experience, peak performance, and "flow." Characteristics of these phenomena are compared, along with factors influencing the ability to experience such peak moments. Csikszentmihalyi's flow models are examined with regard to perceived levels…

  10. The Understanding of "Concept Study" in Teachers' Professional Learning: A Lived Experience of Complexity Inquiry

    ERIC Educational Resources Information Center

    Wang, Xiong

    2015-01-01

    This paper used narrative to present the author's understanding process of "concept study" in teachers' professional learning. The understanding process was advanced by several questions emerging from the preparation of doing "concept study". Thus, the several questions and their solutions became the threads of the narrative.…

  11. Understanding the Seed-Mediated Growth of Gold Nanorods through a Fractional Factorial Design of Experiments.

    PubMed

    Burrows, Nathan D; Harvey, Samantha; Idesis, Fred A; Murphy, Catherine J

    2017-02-28

    Since the development of simple, aqueous protocols for the synthesis of anisotropic metal nanoparticles, research into many promising, valuable applications of gold nanorods has grown considerably, but a number of challenges remain, including gold-particle yield, robustness to minor impurities, and precise control of gold nanorod surface chemistry. Herein we present the results of a composite fractional factorial series of experiments designed to screen seven additional potential avenues of control and to understand the seed-mediated silver-assisted synthesis of gold nanorods. These synthesis variables are the amount of sodium borohydride used and the rate of stirring when producing seed nanoparticles, the age of and the amount of seeds added, the reaction temperature, the amounts of silver nitrate and ascorbic acid added, and the age of the reduced growth solution before seed nanoparticles are added to initiate rod formation. This statistical experimental design and analysis method, besides determining which experimental variables are important and which are not when synthesizing gold nanorods (and quantifying their effects), gives further insight into the mechanism of growth by measuring the degree to which variables interact with each other by mapping out their mechanistic connections. This work demonstrates that when forming gold nanorods by the reduction of auric ions by ascorbic acid onto seed nanoparticles, ascorbic acid determines how much gold is reduced, and the amount of seeds determine how it is divided, yet both influence the intrinsic growth rates, in both width and length, of the forming nanorods. Furthermore, this work shows that the reduction of gold proceeds via direct reduction on the surface of seeds and not through a disproportionation reaction. Further control over the length of gold nanorods can be achieved by tuning the amount of silver nitrate or the reaction temperature. This work shows that silver does not directly influence rod length or

  12. Grade Retention: An Exploration of the Pedagogical Experiences and Attitudes of Elementary Principals that Influence Decisions to Retain Students in a Grade

    ERIC Educational Resources Information Center

    DelConte, Jill

    2011-01-01

    For decades there has been an on-going debate regarding whether or not retention is the best strategy to use for students who are not meeting academic success--whether determined by a test, grades, or standards. Much of the research has indicated that little is gained academically over time by retaining students, but even more significant are the…

  13. Tritium retention in TFTR

    NASA Astrophysics Data System (ADS)

    Skinner, C. H.; Mueller, D.; Walters, R. T.; TFTR Team; Causey, R.; Luckhardt, S.; Hirooka, J.

    1996-11-01

    The large tritium inventories projected for ITER pose an important constraint in the design of plasma facing components and the selection of first wall materials. Three years of deuterium-tritium operation in TFTR has provided a special opportunity to address the issues of tritium retention in a tokamak environment. More than 18 kCi of tritium has been injected into the torus via neutral beam injection and gas puffs and approximately half of this amount was retained in the vacuum vessel.(C.H. Skinner et al.), PPPL 3172 (Jan 1995). Tritium has been successfully removed by glow discharges, exposure to room air and other techniques and it is not a constraint on continued operations. A vacuum opening is scheduled for September 1996 and we plan to extract samples of tritiated carbon dust and flakes from the limiter and vacuum vessel for elemental and chemical analysis. We will present the TFTR experience in tritium recycling, retention and removal and its implications for ITER.

  14. Impact of plant growth and morphology and of sediment concentration on sediment retention efficiency of vegetative filter strips: Flume experiments and VFSMOD modeling

    NASA Astrophysics Data System (ADS)

    Lambrechts, Thomas; François, Sébastien; Lutts, Stanley; Muñoz-Carpena, Rafael; Bielders, Charles L.

    2014-04-01

    Vegetative filter strips (VFS) implemented downstream to the source of pollution can trap sediments and thus limit sediment export from agricultural fields. However, their retention efficiencies are determined by many factors, among others the type of plant species and its growth stage. The impact of plant growth and morphology, as well as of incoming sediment concentration, on the efficiency of VFS to trap sediments was assessed by means of an experimental flume. Two different plant species were tested, Lolium perenne and Trifolium repens, after 2 and 4 months of plant growth and for 2 different incoming silty-loam sediment concentrations. Measured retention efficiencies were compared to simulated values using VFSMOD based on goodness-of-fit indicators that take into account uncertainty linked to the measurements. The sediment storage capacity upstream of the VFS was limited in terms of mass, and therefore an increase in sediment concentration led to a decrease in sediment retention efficiency. After 2 months of plant growth, plant morphology affected the VFS potential to trap sediments, as reflected in the higher retention efficiency of T. repens due to its creeping shoot architecture. However, plant growth and development modified the plant morphology and VFS trapping potential. Indeed, L. perenne VFS retention efficiency increased from 35% after 2 months of growth to 50% after 4 months, due to the tillering capacity of grass species. Conversely, the trapping efficiency of T. repens decreased from 49% to 40% after 4 months. This highlights the possible degradation of VFS with time, which in the case of T.repens was due to an increased heterogeneity of plant density within the strips. These modifications of plant characteristics with growth stage, which affected sediment trapping efficiencies, can be effectively integrated into mechanistic models like VFSMOD, mainly through stem spacing and Manning's surface roughness coefficient inputs. Since these parameters

  15. Understanding Students' Precollege Experiences with Racial Diversity: The High School as Microsystem

    ERIC Educational Resources Information Center

    Park, Julie J.; Chang, Stephanie H.

    2015-01-01

    Few qualitative studies consider how high school experiences affect readiness for diversity engagement in college. Using data from an ethnographic case study, three central trends (student experiences within homogeneous high schools, racial divisions within diverse high schools, and students who attended diverse high schools but had little…

  16. Postcards from Heaven and Hell: Understanding the Near-Death Experience through Art

    ERIC Educational Resources Information Center

    Rominger, Ryan

    2010-01-01

    Art making offers the opportunity to reflect upon ineffable experiences, including those surrounding death and dying. This article examines the artwork of two research participants who each reported a near-death experience (NDE). A trans-personal model was used to elicit the narratives and artwork of two individuals: one who experienced a pleasant…

  17. Understanding Students' Experiences in Their Own Words: Moving beyond a Basic Analysis of Student Engagement

    ERIC Educational Resources Information Center

    Wong, Arch Chee Keen

    2015-01-01

    This study examines the lived experiences of students as expressed in their reflections on their experiences of learning at Ambrose University in Calgary. It uses quantitative outcomes-related data from the National Survey of Student Engagement and the Theological School Survey of Student Engagement to illuminate qualitative data obtained through…

  18. Understanding the Work-Life Experiences and Goals of Women Middle Managers in Higher Education

    ERIC Educational Resources Information Center

    Hankinson, Marie

    2013-01-01

    Middle managers in higher education hold diverse titles and perform a variety of roles. Women represent a large portion of this midlevel management, but there is limited research exploring their experiences. As a result, little is known about women middle managers' career trajectories and what effect their experiences have on their future career…

  19. Understanding the Experiences of Adult English as a Second Language Instructors: A Case Study

    ERIC Educational Resources Information Center

    Dorman, Marni Alexandra

    2010-01-01

    Positioned within the social constructivist view of learning that individuals make meaning from their experiences and through their social actions and interactions, this qualitative study explores the ways in which nine instructors of underprepared adult English as a Second Language students made meaning of their classroom experiences. Through…

  20. Understanding the Science Experiences of Successful Women of Color: Science Identity as an Analytic Lens

    ERIC Educational Resources Information Center

    Carlone, Heidi B.; Johnson, Angela

    2007-01-01

    In this study, we develop a model of science identity to make sense of the science experiences of 15 successful women of color over the course of their undergraduate and graduate studies in science and into science-related careers. In our view, science identity accounts both for how women make meaning of science experiences and how society…

  1. Novel experiments for understanding the shallow-land burial of low-level radioactive wastes

    SciTech Connect

    DePoorter, G.L.; Abeele, W.V.; Hakonson, T.E.; Burton, B.W.; Perkins, B.A.

    1982-01-01

    Three field experiments that will provide data on water movement in SLB facilities are described. The experiments are designed to measure water movement, to quantify techniques to control water movement and to determine the effects of surface moisture content fluctuations on liquid and vapor movement back to the surface.

  2. Understanding Students' Experiments--What Kind of Support Do They Need in Inquiry Tasks?

    ERIC Educational Resources Information Center

    Arnold, Julia Caroline; Kremer, Kerstin; Mayer, Jürgen

    2014-01-01

    Inquiry learning is a widely recognized method for fostering inquiry competence in science education. Nevertheless, there is discussion about how to best support students while working on inquiry tasks (in this case: experiments on causal relationships). To identify the kind of support students need in order to design experiments in upper grades,…

  3. What Do We See?: Extending Understanding of Visual Experience in the Art Therapy Encounter

    ERIC Educational Resources Information Center

    Fenner, Patricia

    2012-01-01

    Visual experience and meaning making in art therapy constitute more than looking at the image created. Clients and therapists utilize the environment of therapy in ways that have been hitherto unrecognized. This article presents a key finding from an art-based study of the experience of the art therapy room from the perspectives of client and…

  4. Understanding Accounting as a Career: An Immersion Work Experience for Students Making Career Decisions

    ERIC Educational Resources Information Center

    McGrath, Dianne; Murphy, Daniel

    2016-01-01

    This paper reports on a project which is designed to increase the participation of high school students in accounting work experience placements. The focus of the paper is on an Australian-based project which overcomes the identified barriers to offering high school accounting work experience placements with a resultant increase in the number and…

  5. Understanding Field Experiences in Traditional Teacher Preparation Programs in Missouri. REL 2016-145

    ERIC Educational Resources Information Center

    Meyer, Stephen J.

    2016-01-01

    The purpose of this study was to describe the characteristics of field experiences in traditional teacher preparation programs completed by first-year teachers in Missouri and how experiences vary by teaching certificate type. This descriptive study is based on data from a survey administered in early 2015 to first-year teachers in Missouri public…

  6. Postdoctoral Positions as Preparation for Desired Careers: A Narrative Approach to Understanding Postdoctoral Experience

    ERIC Educational Resources Information Center

    Chen, Shuhua; McAlpine, Lynn; Amundsen, Cheryl

    2015-01-01

    Doing a "postdoc" following a doctorate is becoming more and more common worldwide as the pre-tenure job market continues shrinking in relation to the number of PhD graduates. Yet, behind statistics and descriptions of collective experience, how individuals experience the postdoctoral period is largely unknown, especially how they use…

  7. Shared Communities and Shared Understandings: The Experiences of Asian Women in a British University

    ERIC Educational Resources Information Center

    Bhopal, Kalwant

    2008-01-01

    This article examines Asian women's experiences of belonging to communities of practice within higher education in Britain. The research explores the ways in which women engage in friendship and support networks, how they negotiate their identities and their experiences of being marginalised and "different". The research argues that…

  8. Using Wenger's Social Theory of Learning to Examine University Teachers' Understanding of How Instructional Technology Affects Their Experience in Practice

    ERIC Educational Resources Information Center

    Adams, Laura L.

    2010-01-01

    The purpose of this study was to take an exploratory look at how university teachers come to understand their experience in educational practice and their professional role as teachers who integrate instructional technology into their coursework using the framework provided by Wenger's Social Theory of Learning. University faculty who teach in a…

  9. Understanding Students' Experience of Transition from Lecture Mode to Case-Based Teaching in a Management School in India

    ERIC Educational Resources Information Center

    Roy, Subhadip; Banerjee, Pratyush

    2012-01-01

    In this study, we aimed to understand experience of students about transition from lecture mode to case study pedagogy in business management courses. Indian education system is predominantly a follower of the lecture mode of teaching from the grass-root level till graduation. Hence Indian students are relatively less familiar with the case based…

  10. Understanding Black Male Student Athletes' Experiences at a Historically Black College/University: A Mixed Methods Approach

    ERIC Educational Resources Information Center

    Cooper, Joseph N.; Hall, Jori

    2016-01-01

    The purpose of this article is to describe how a mixed methods approach was employed to acquire a better understanding of Black male student athletes' experiences at a historically Black college/university in the southeastern United States. A concurrent triangulation design was incorporated to allow different data sources to be collected and…

  11. Toward a Cultural Perspective and Understanding of the Disability and Deaf Experience in Special and Multicultural Education

    ERIC Educational Resources Information Center

    Johnson, John R.; McIntosh, Angela S.

    2009-01-01

    This position paper provides a rationale for infusing cultural perspectives and understandings of the Disability and Deaf experiences into special and multicultural education teacher preparation programs. Substantial evidence of well-established features of the Disability community and Deaf community that meet definitional criteria for culture as…

  12. Understanding Tuberculosis: Perspectives and Experiences of the People of Sabah, East Malaysia

    PubMed Central

    2010-01-01

    Malaysia is a country with the intermediate burden of tuberculosis (TB). TB is still a public-health problem in Sabah, one of the two states in East Malaysia. In 2007, the state of Sabah contributed slightly more than 3,000 of 16,129 new and relapse cases reported in the country. It has a notification rate of two and a half times that of the country's. Very few studies on TB have been conducted in Sabah, and there is little documentation on the perceptions of TB patients and the community about TB, healthcare-seeking behaviour, and impact of TB on the people of Sabah. A qualitative study was conducted in 2006 in seven districts in Sabah to assess the knowledge and perceptions of TB patients and the community about TB, also to know the experiences of healthcare services, and to examine the impact of TB on patients and families. Purposive sampling identified 27 TB patients and 20 relatives and community members who were interviewed using a set of questions on knowledge, perceptions about TB, healthcare-seeking behaviour, and impact of TB. A further 11 health staff attended informal discussions and feedback sessions. Most interviews were taped and later translated. Data were analyzed using thematic content analysis. Ninety-six percent of the respondents did not know the cause of TB. Some thought that TB occurred due to a ‘tear’ in the body or due to hard work or inflammation while others thought that it occurred due to eating contaminated food or due to sharing utensils or breathing space with TB patients. Although the germ theory was not well-known, 98% of the respondents believed that TB was infectious. Some patients did not perceive the symptoms they had as those of TB. The prevailing practice among the respondents was to seek modern medicine for cure. Other forms of treatment, such as traditional medicine, were sought if modern medicine failed to cure the disease. TB was still a stigmatizing disease, and the expression of this was in both perceived and enacted

  13. Understanding the experiences of a group of Yemeni students in an ESL science class

    NASA Astrophysics Data System (ADS)

    Fradi, Gihan

    American classrooms are experiencing an influx of diverse language speaking students while for science educators the study of EBL students' learning in science classrooms is a relatively new field (Lee & Buxton, 2010). At the same time there is a growing emphasis on the importance of science practices (NGSS). This poses significant challenges for science educators who are enacting science curriculum that supports all students' learning. Supporting EBL students' academic achievement is significant because literacy is important for students' access to economic and social benefits that come with science literacy (Atwater, 1996). The purpose of this study was to examine the socio-linguistic challenges that a specific group of EBL students (Yemeni) faced and the extent to which such challenges affected their academic performance in science. These challenges are related to linguistic and cultural interactions, which can lead to conflicts between student and school, thereby interfering with the effectiveness of their education. This study also examined these students' and their science teacher's perspectives on strategies that can be used to facilitate their language acquisition during science class and help them become active participants in the school and classroom communities. The study used a qualitative interpretive research methodology and involved four Arab-American EBL students (two males and two females) from Yemen, who had been in the US for different periods of time. The amount of time these students had been in the US was important to examine differences in their acculturation and challenges they faced. Similarly, the use of female and male student participants was important to understand the impact of gender in the lived experiences of these students. The results of the study indicated that all the participants struggled with linguistic, social, and cultural aspects of their life in an American high school. These in turn led to a sense of being different

  14. Influence of student-designed experiments with fast plants on their understanding of plants and of scientific inquiry

    NASA Astrophysics Data System (ADS)

    Akey, Ann Kosek

    2000-10-01

    This dissertation investigates the influence of student designed experiments with Fast Plants in an undergraduate agroecology course on the students' conceptual understanding of plant life cycles and on their procedural understanding of scientific experimentation. It also considers students' perspectives on the value of these experiences. Data sources included semi-structured interviews with students and the instructor, a written task, course evaluations, and observations of class meetings. Students came into the course having strong practical experience with plants from their agricultural backgrounds. Students did not always connect aspects of plant biology that they studied in class, particularly respiration and photosynthesis, to plant growth requirements. The instructor was able to bridge the gap between some practical knowledge and textbook knowledge with experiences other than the Fast Plant project. Most students held an incomplete picture of plant reproduction that was complicated by differences between agricultural and scientific vocabulary. There is need for teaching approaches that help students tie together their knowledge of plants into a cohesive framework. Experiences that help students draw on their background knowledge related to plants, and which give students the opportunity to examine and discuss their ideas, may help students make more meaningful connections. The Fast Plant project, a positive experience for most students, was seen by these undergraduate students as being more helpful in learning about scientific experimentation than about plants. The process of designing and carrying out their own experiments gave students insight into experimentation, provoked their curiosity, and resulted in a sense of ownership and accomplishment.

  15. Toward a more complete understanding of the link between multicultural experience and creativity.

    PubMed

    Maddux, William W; Leung, Angela Ka-Yee; Chiu, Chi-Yue; Galinsky, Adam D

    2009-01-01

    Responds to G. J. Rich's comments on the current author's original article which presented evidence supporting the idea that multicultural experience can facilitate creativity. Rich has argued that our review, although timely and important, was somewhat limited in scope, focusing mostly on smaller forms of creativity ("little c": e.g., paper-and-pencil measures of creativity) as well as on larger forms of multicultural experience ("Big M": e.g., living in a foreign country). We agree with many aspects of Rich's assessment. The issue of whether different forms of multicultural experience can affect Big C creativity is of interest to both scholars and laypeople because creative breakthroughs can literally alter the course of human progress. The response to our article, including Rich's reply, supports our view that the interest in multicultural experience and creativity is far from exhausted; future research will certainly uncover important new insights.

  16. Understanding of the late Michelson's experiments that confirmed the aether existence

    NASA Astrophysics Data System (ADS)

    Rek, Radosław

    2016-06-01

    This paper contains a brief discussion of results of two experiments made by Albert Michelson in the years of 1923-1925. According to the paper written by the Nobel Prize winner the aether dragging should exist.

  17. Understanding the subjective experiences and needs of patients as they approach death.

    PubMed

    Sartori, Penny

    When patients are approaching the end of life their spiritual as well as physical needs should be considered. This article considers how nurses can best support patients who are dying and work to ensure they experience a peaceful transition to death. Attending to their spiritual needs is shown to be of utmost importance; the near death and end of life experiences that some patients may have are also taken into consideration.

  18. Understanding Biases in Ribosome Profiling Experiments Reveals Signatures of Translation Dynamics in Yeast

    PubMed Central

    Hussmann, Jeffrey A.; Patchett, Stephanie; Johnson, Arlen; Sawyer, Sara; Press, William H.

    2015-01-01

    Ribosome profiling produces snapshots of the locations of actively translating ribosomes on messenger RNAs. These snapshots can be used to make inferences about translation dynamics. Recent ribosome profiling studies in yeast, however, have reached contradictory conclusions regarding the average translation rate of each codon. Some experiments have used cycloheximide (CHX) to stabilize ribosomes before measuring their positions, and these studies all counterintuitively report a weak negative correlation between the translation rate of a codon and the abundance of its cognate tRNA. In contrast, some experiments performed without CHX report strong positive correlations. To explain this contradiction, we identify unexpected patterns in ribosome density downstream of each type of codon in experiments that use CHX. These patterns are evidence that elongation continues to occur in the presence of CHX but with dramatically altered codon-specific elongation rates. The measured positions of ribosomes in these experiments therefore do not reflect the amounts of time ribosomes spend at each position in vivo. These results suggest that conclusions from experiments in yeast using CHX may need reexamination. In particular, we show that in all such experiments, codons decoded by less abundant tRNAs were in fact being translated more slowly before the addition of CHX disrupted these dynamics. PMID:26656907

  19. Understanding Biases in Ribosome Profiling Experiments Reveals Signatures of Translation Dynamics in Yeast.

    PubMed

    Hussmann, Jeffrey A; Patchett, Stephanie; Johnson, Arlen; Sawyer, Sara; Press, William H

    2015-12-01

    Ribosome profiling produces snapshots of the locations of actively translating ribosomes on messenger RNAs. These snapshots can be used to make inferences about translation dynamics. Recent ribosome profiling studies in yeast, however, have reached contradictory conclusions regarding the average translation rate of each codon. Some experiments have used cycloheximide (CHX) to stabilize ribosomes before measuring their positions, and these studies all counterintuitively report a weak negative correlation between the translation rate of a codon and the abundance of its cognate tRNA. In contrast, some experiments performed without CHX report strong positive correlations. To explain this contradiction, we identify unexpected patterns in ribosome density downstream of each type of codon in experiments that use CHX. These patterns are evidence that elongation continues to occur in the presence of CHX but with dramatically altered codon-specific elongation rates. The measured positions of ribosomes in these experiments therefore do not reflect the amounts of time ribosomes spend at each position in vivo. These results suggest that conclusions from experiments in yeast using CHX may need reexamination. In particular, we show that in all such experiments, codons decoded by less abundant tRNAs were in fact being translated more slowly before the addition of CHX disrupted these dynamics.

  20. Mathematical Understanding and Proving Abilities: Experiment with Undergraduate Student by Using Modified Moore Learning Approach

    ERIC Educational Resources Information Center

    Maya, Rippi; Sumarmo, Utari

    2011-01-01

    This paper reports findings of a post test experimental control group design conducted to investigate the role of modified Moore learning approach on improving students' mathematical understanding and proving abilities. Subjects of study were 56 undergraduate students of one state university in Bandung, who took advanced abstract algebra course.…

  1. Reasoning, Not Recipes: Helping Your Students Develop Statistical Understanding and Enjoy the Experience!

    ERIC Educational Resources Information Center

    Mooney, Gai

    2010-01-01

    Statistics is often presented to students as a series of algorithms to be learnt by heart and applied at the appropriate time to get "the correct answer". This approach, while it may in fact produce the right answer, has been shown to be minimally effective at helping students understand the underlying statistical concepts. As Holmes noted,…

  2. Developing Children's Conceptual Understanding of Area Measurement: A Curriculum and Teaching Experiment

    ERIC Educational Resources Information Center

    Huang, Hsin-Mei E.; Witz, Klaus G.

    2011-01-01

    The present study examined the effectiveness of three instructional treatments which had different combinations of mathematical elements regarding 2-dimensional (2-D) geometry and area measurement for developing 4th-grade children's understanding of the formulas for area measurement and their ability to solve area measurement problems.…

  3. Do Signers Understand Regional Varieties of a Sign Language? A Lexical Recognition Experiment

    ERIC Educational Resources Information Center

    Stamp, Rose

    2016-01-01

    The degree of mutual intelligibility of British Sign Language (BSL) regional varieties has been a subject of some debate. Recent research in which dyads of signers from contrasting regional backgrounds engaged in a conversational task showed no problems understanding one another. The present study investigated signers' knowledge of different BSL…

  4. Coming to Understand Diversity and Education: Life Experiences and Educational Opportunities

    ERIC Educational Resources Information Center

    Chamberlain, Steven Paul

    2015-01-01

    Coming to understand how cultural differences influence interactions between educators and students and their parents is a complex and perhaps life-long discovery. Culture helps to define groups' belief systems and expectations for appropriate behavior, often at a hidden level. Pre-service teachers need multiple opportunities to interact with…

  5. Pre-Service Teachers' Experiences Implementing a Hybrid Curriculum: Sport Education and Teaching Games for Understanding

    ERIC Educational Resources Information Center

    Stran, Margaret; Sinelnikov, Oleg; Woodruff, Elizabeth

    2012-01-01

    A hybrid Sport Education (SE) and Teaching Games for Understanding (TGfU) pedagogical model shifts responsibilities to students and enhances game play by focusing on tactical problems. The purpose of this study was to (1) examine pre-service teachers' (PTs) perceptions teaching a SE-TGfU hybrid; and (2) identify facilitators and inhibitors that…

  6. Understanding Teachers' Experience of Teaching American History: A Study of TAH Grant Participants

    ERIC Educational Resources Information Center

    Ables, Connie J.

    2011-01-01

    The purpose of this study was to follow six middle and high school TAH teachers and study their understanding and manifestations of the aims of the grant. Currently, there are few dissertations about the TAH program and none that address it as a qualitative study. This study focused on the ways that teachers experienced the grant including four…

  7. Complex Problem Solving in Radiologic Technology: Understanding the Roles of Experience, Reflective Judgment, and Workplace Culture

    ERIC Educational Resources Information Center

    Yates, Jennifer L.

    2011-01-01

    The purpose of this research study was to explore the process of learning and development of problem solving skills in radiologic technologists. The researcher sought to understand the nature of difficult problems encountered in clinical practice, to identify specific learning practices leading to the development of professional expertise, and to…

  8. Infants' Social and Motor Experience and the Emerging Understanding of Intentional Actions

    ERIC Educational Resources Information Center

    Brandone, Amanda C.

    2015-01-01

    During the first year of life, infants possess some of the key social--cognitive abilities required for success in a social world: Infants interpret others' actions in terms of their intentions and can use this understanding prospectively to generate predictions about others' behavior. Exactly how these foundational abilities develop is currently…

  9. An Intuitive Graphical Approach to Understanding the Split-Plot Experiment

    ERIC Educational Resources Information Center

    Robinson, Timothy J.; Brenneman, William A.; Myers, William R.

    2009-01-01

    While split-plot designs have received considerable attention in the literature over the past decade, there seems to be a general lack of intuitive understanding of the error structure of these designs and the resulting statistical analysis. Typically, students learn the proper error terms for testing factors of a split-plot design via "expected…

  10. The Role of Motor Experience in Understanding Action Function: The Case of the Precision Grasp

    ERIC Educational Resources Information Center

    Loucks, Jeff; Sommerville, Jessica A.

    2012-01-01

    Recent evidence suggests adults and infants selectively attend to features of action, such as how a hand contacts an object. The current research investigated whether this bias stems from infants' processing of the functional consequences of grasps: understanding that different grasps afford different future actions. A habituation paradigm…

  11. Learning Informally to Use Teaching Games for Understanding: The Experiences of a Recently Qualified Teacher

    ERIC Educational Resources Information Center

    O'Leary, Nick

    2014-01-01

    This article reports on a study of one recently qualified teacher's employment of the Teaching Games for Understanding (TGfU) model in a UK secondary school. The study sought to examine how the teacher, not formally educated in its use, delivered TGfU and to identify those factors that led to this interpretation of the model. Occupational…

  12. What Factors Determine the Retention Behavior of Engineered Nanomaterials in Saturated Porous Media?

    PubMed

    Goldberg, Eli; McNew, Coy; Scheringer, Martin; Bucheli, Thomas D; Nelson, Peter; Hungerbühler, Konrad

    2017-02-16

    A fundamental problem associated with the vertical transport of engineered nanomaterials (ENMs) in saturated porous media is the occurrence of nonexponential, for example, nonmonotonic or linearly increasing, retention profiles. To investigate this problem, we compiled an extensive database of ENMs transport experiments in saturated porous media. Using this database we trained a decision tree that shows the order of importance, and range of influence, of the physicochemical factors that control the retention profile shape. Our results help identify domains where current particle-transport models can be used, but also highlight, for the first time, large domains where nonexponential retention profiles dominate and new approaches are needed to understand ENM transport. Importantly, highly advective flow and high ENM influent mass can mask the influence of other physicochemical factors on the retention profile shape; notably, this occurs in 50% of the experiments investigated. Where the relationship between physicochemical factors and retention profile shape can be investigated in detail, our results agree with, and provide validation for, the current understanding of how these factors influence ENM transport.

  13. Mouse vision as a gateway for understanding how experience shapes neural circuits

    PubMed Central

    Priebe, Nicholas J.; McGee, Aaron W.

    2014-01-01

    Genetic programs controlling ontogeny drive many of the essential connectivity patterns within the brain. Yet it is activity, derived from the experience of interacting with the world, that sculpts the precise circuitry of the central nervous system. Such experience-dependent plasticity has been observed throughout the brain but has been most extensively studied in the neocortex. A prime example of this refinement of neural circuitry is found in primary visual cortex (V1), where functional connectivity changes have been observed both during development and in adulthood. The mouse visual system has become a predominant model for investigating the principles that underlie experience-dependent plasticity, given the general conservation of visual neural circuitry across mammals as well as the powerful tools and techniques recently developed for use in rodent. The genetic tractability of mice has permitted the identification of signaling pathways that translate experience-driven activity patterns into changes in circuitry. Further, the accessibility of visual cortex has allowed neural activity to be manipulated with optogenetics and observed with genetically-encoded calcium sensors. Consequently, mouse visual cortex has become one of the dominant platforms to study experience-dependent plasticity. PMID:25324730

  14. Understanding Doctoral Nursing Students' Experiences of Blended Learning: A Qualitative Study.

    PubMed

    Emami Sigaroudi, Abdolhossein; Ghiyasvandian, Shahrzad; Nikbakht Nasabadi, Alireza

    2016-11-01

    The concept of blended learning in the field of nursing and medicine has been accepted. Blended learning has been extensively used thanks to the development of communication technologies and the availability of Internet services. Meanwhile, experiences-based research, by all accounts, can help the expansion of such a learning modality. Therefore, this study was designed to explain nursing doctoral students' experiences of blended learning. To attain this goal, a descriptive phenomenology method was used to illustrate experiences as they are experienced by the participants in the study. With regard to the nature of the investigated phenomena and the existing methods for the inductive analysis, Colaizzi's method of data analysis was used. The findings of the study led to the discovery of three main themes: "failure", "synergy" and "specific interaction". Each of the themes has been further divided into some sub-themes.

  15. Is there a universal understanding of vulnerability? Experiences with Russian and Romanian trainees in research ethics.

    PubMed

    Loue, Sana; Loff, Bebe

    2013-12-01

    Vulnerability of participants in research and the provision of special protections for vulnerable research participants are key concepts in research ethics. Despite international consensus requiring special protections for vulnerable research participants, both the concept of vulnerability and the nature and adequacy of strategies to reduce vulnerability remain vague and, consequently, are subject to varying interpretations. We report on observations of the challenges faced in understanding this key concept by 20 Russian and Romanian trainees participating in a one-year M.A. training program in research ethics from 2000 through 2011. We describe how trainees' understanding of and appreciation for the need for special protections of vulnerable research participants was nurtured. This paper is part of a collection of papers analyzing the Fogarty International Center's International Research Ethics Education and Curriculum Development program.

  16. Climate Observing System Simulation Experiments: Understanding what we have and what we need

    NASA Astrophysics Data System (ADS)

    Weatherhead, E. C.

    2015-12-01

    Observations to monitor the climate and to support climate research are critical to advancing the science of climate change. Some parameters appear to be well monitored, while in other cases, our understanding is directly limited by the lack of quality observations. Detecting trends, attributing change and understanding climate feedbacks require a variety of observations. Making use of historical datasets, we can identify the most critical needs for continued and new observing systems. Decisions about accuracy, spatial resolution, and temporal frequency need to be made judiciously with a careful analysis of the requirements needed to specific scientific questions. This presentation will show initial results from comparing natural variability to the specific questions of detecting trends and addressing climate feedback questions. Combining the high resolution weather Observing System Simulation Exkperiments with the longer timescale needs of climate research, we can make responsible recommendations on future observing systems as well as identify the necessary continuation of existing observing systems.

  17. Is There a Universal Understanding of Vulnerability? Experiences with Russian and Romanian Trainees in Research Ethics

    PubMed Central

    Loue, Sana; Loff, Bebe

    2014-01-01

    Vulnerability of participants in research and the provision of special protections for vulnerable research participants are key concepts in research ethics. Despite international consensus requiring special protections for vulnerable research participants, both the concept of vulnerability and the nature and adequacy of strategies to reduce vulnerability remain vague and, consequently, are subject to varying interpretations. We report on observations of the challenges faced in understanding this key concept by 20 Russian and Romanian trainees participating in a one-year M.A. training program in research ethics from 2000 through 2011. We describe how trainees’ understanding of and appreciation for the need for special protections of vulnerable research participants was nurtured. This paper is part of a collection of papers analyzing the Fogarty International Center's International Research Ethics Education and Curriculum Development program. PMID:24384513

  18. Rethinking the Relationship between Social Experience and False-Belief Understanding: A Mentalistic Account

    PubMed Central

    Roby, Erin; Scott, Rose M.

    2016-01-01

    It was long assumed that the capacity to represent false beliefs did not emerge until at least age four, as evidenced by children’s performance on elicited-response tasks. However, recent evidence that infants appear to demonstrate false-belief understanding when tested with alternative, non-elicited-response measures has led some researchers to conclude that the capacity to represent beliefs emerges in the 1st year of life. This mentalistic view has been criticized for failing to offer an explanation for the well-established positive associations between social factors and preschoolers’ performance on elicited-response false-belief tasks. In this paper, we address this criticism by offering an account that reconciles these associations with the mentalistic claim that false-belief understanding emerges in infancy. We propose that rather than facilitating the emergence of the capacity to represent beliefs, social factors facilitate the use of this ability via effects on attention, inference, retrieval, and response production. Our account predicts that the relationship between social factors and false-belief understanding should not be specific to preschoolers’ performance in elicited-response tasks: this relationship should be apparent across the lifespan in a variety of paradigms. We review an accumulating body of evidence that supports this prediction. PMID:27857702

  19. Hydrogen retention in ion irradiated steels

    SciTech Connect

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

    1998-11-01

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

  20. The Theory of Planned Behaviour as a Framework for Understanding Parental Experiences with Homework

    ERIC Educational Resources Information Center

    McGregor, Sharon A.; Knoll, Monja A.

    2015-01-01

    Research into parental homework-related experiences has predominantly focused on parental attitudes to homework. This research has shown that parental attitudes can affect the formation of attitudes in children and subsequently their academic success. Most research has focused on a secondary school context, but there is still a lack of knowledge…

  1. Latent Profiles among Sexual Assault Survivors: Understanding Survivors and Their Assault Experiences

    ERIC Educational Resources Information Center

    Macy, Rebecca J.; Nurius, Paula S.; Norris, Jeanette

    2007-01-01

    Little guidance exists about how to tailor empowerment and resistance sexual assault programming to be responsive to varying groups of women. Using an investigation of 415 college women who completed a self-administered survey about a range of sexually aggressive experiences by a known male assailant, this investigation tested for distinct…

  2. Understanding the Learning Experiences of Postgraduate Latin American Students in a UK Context: A Narrative Approach

    ERIC Educational Resources Information Center

    James, Gwyneth

    2013-01-01

    Researching the learning experiences of postgraduate students requires a different type of qualitative research to enable access to areas of their lives which may well remain hidden with more conventional methods of research. Narrative inquiry as both method and methodology allows such access. In this article, I focus on the use, appropriateness,…

  3. Broadening Student Understanding of Wartime Experience through Original Works of Art and Personal Accounts

    ERIC Educational Resources Information Center

    Potter, Lee Ann

    2013-01-01

    Tracy A. Sugarman served in the U.S. Navy as a lieutenant, junior grade, in the European theater during World War II. During his years of service from 1942-45, in addition to writing letters home, he recorded his experiences through original artwork. His sketches and watercolor paintings, completed before, during, and after D-Day, with titles such…

  4. "Virtual" Experiment for Understanding the Electrocardiogram and the Mean Electrical Axis.

    ERIC Educational Resources Information Center

    Anderson, Jamie; DiCarlo, Stephen E.

    2000-01-01

    Describes a virtual experiment designed to introduce students to the theory and application of the electrocardiogram (ECG) and the mean electrical axis (MEA). Students are asked to reduce and analyze data, calculate and plot the MEA, and answer questions in the inquiry-based, experimental activity. (Author/WRM)

  5. Commentary: Explicit Attention to Age and Gender Disparities is Key to Understanding Adolescent Experiences and Outcomes

    ERIC Educational Resources Information Center

    Blanc, Ann K.; Bruce, Judith

    2013-01-01

    This special issue addresses an ambitious set of concerns around the experience of adolescents in the majority world: expanded models of development, successful models of intervention, and the impact of globalization. The papers, which vary widely in both substance and methodology, make a substantial contribution to pushing forward the boundaries…

  6. Understanding the Experiences of Gifted Education Teachers and Fidelity of Implementation in Rural Schools

    ERIC Educational Resources Information Center

    Azano, Amy Price; Callahan, Carolyn M.; Missett, Tracy C.; Brunner, Marguerite

    2014-01-01

    Approximately one quarter of American students attend rural schools; however, the needs of these students are often overlooked in education policy despite well-documented limited financial resources and pervasive poverty. Relatively little is known about the experiences of gifted students in rural areas and even less about the teachers serving…

  7. School Counsellors' Understanding of Non-Suicidal Self-Injury: Experiences and International Variability

    ERIC Educational Resources Information Center

    Duggan, Jamie M.; Heath, Nancy L.; Toste, Jessica R.; Ross, Shana

    2011-01-01

    Non-suicidal self-injury (NSSI) is a concern among professionals working with youth. The present study examined school counsellors' experiences, training and school preparedness, perceived knowledge, beliefs, and intervention approaches related to NSSI. Participants were 470 school counsellors (417 female, 53 male) from across North America (156…

  8. Educating an "iPod" Generation: Undergraduate Attitudes, Experiences and Understanding of Vodcast and Podcast Use

    ERIC Educational Resources Information Center

    Parson, Vanessa; Reddy, Peter; Wood, Jon; Senior, Carl

    2009-01-01

    There is an increasing pressure on university staff to provide ever more information and resources to students. This study investigated student opinions on (audio) podcasts and (video) vodcasts and how well they met requirements and aided learning processes. Two experiments within the Aston University looked at student opinion on, and usage of,…

  9. Towards Understanding the Two Way Interaction Effects of Extraversion and Openness to Experience on Career Commitment

    ERIC Educational Resources Information Center

    Arora, Ridhi; Rangnekar, Santosh

    2016-01-01

    In this study, we examined potential two-way interaction effects of the Big Five personality traits extraversion and openness to experience on career commitment measured in terms of three components of career identity, career resilience, and career planning. Participants included 450 managers from public and private sector organizations in North…

  10. Definitions of Bullying: Age Differences in Understanding of the Term, and the Role of Experience

    ERIC Educational Resources Information Center

    Monks, Claire P.; Smith, Peter K.

    2006-01-01

    We report two studies that examine age differences in pupils' and parents' definitions of the term "bullying," and possible reasons for these including the role of specific experiences. Study 1 compared definitions of "bullying" given by participants in four age groups; 4 to 6 years, 8 years, 14 years and adult. Participants were shown/read 17…

  11. Understanding Fluorescence Measurements through a Guided-Inquiry and Discovery Experiment in Advanced Analytical Laboratory

    ERIC Educational Resources Information Center

    Wilczek-Vera, Grazyna; Salin, Eric Dunbar

    2011-01-01

    An experiment on fluorescence spectroscopy suitable for an advanced analytical laboratory is presented. Its conceptual development used a combination of the expository and discovery styles. The "learn-as-you-go" and direct "hands-on" methodology applied ensures an active role for a student in the process of visualization and discovery of concepts.…

  12. Physical Pendulum Experiments to Enhance the Understanding of Moments of Inertia and Simple Harmonic Motion

    ERIC Educational Resources Information Center

    Richardson, Tim H.; Brittle, Stuart A.

    2012-01-01

    This paper describes a set of experiments aimed at overcoming some of the difficulties experienced by students learning about the topics of moments of inertia and simple harmonic motion, both of which are often perceived to be complex topics amongst students during their first-year university courses. By combining both subjects in a discussion…

  13. Understanding the Friendship Processes of Individuals with Asperger's Syndrome: A Phenomenological Study of Reflective College Experiences

    ERIC Educational Resources Information Center

    Lee, Kammie Bohlken

    2010-01-01

    This phenomenological study shed light on the reflective college experiences of 11 individuals with Asperger's Syndrome and High Functioning Autism from a competence rather than a deficit model of disability (Biklen, 2005). Using Goleman's model of Social Intelligence (2006) as a theoretical framework, the cognitive, behavioral, and affective…

  14. Recognising Prior Learning: Understanding the Relations among Experience, Learning and Recognition from a Constructivist Perspective

    ERIC Educational Resources Information Center

    Fejes, Andreas; Andersson, Per

    2009-01-01

    This article discusses the relation between experience and learning in the context of recognition of prior learning (RPL) and from an experiential constructivist perspective. The study is based on a case of in-service training, based on RPL, in the care sector for elderly people. The data consist of interviews with actors in this process, which…

  15. Understanding College Students' Lived Experiences in a Diverse Blended Model Class

    ERIC Educational Resources Information Center

    Cook, Sarah Taylor

    2016-01-01

    The current study was used to explore the lived experiences of students enrolled in a college-level course developed within an interinstitutional partnership that leveraged technology platforms, such as Twitter® and online learning management systems, and included the participation of prominent figures from the 1960s Civil Rights Era. The focus of…

  16. Understanding the Lived Experiences of Novice Teachers in an Urban Texas School District

    ERIC Educational Resources Information Center

    Lepisto-Wood, Kimberly

    2013-01-01

    In an urban Texas Independent School District (TXISD), novice teachers leave the field of education for different careers within the first 3 years of employment at a rate that is nearly twice the Texas average and near the top of the national novice teacher attrition rate range. This study examined the lived experiences of 23 TXISD novice teachers…

  17. Differentiated Associations between Childhood Maltreatment Experiences and Social Understanding: A Meta-Analysis and Systematic Review

    ERIC Educational Resources Information Center

    Luke, Nikki; Banerjee, Robin

    2013-01-01

    The extreme parenting experiences encountered by children who are physically abused or neglected place them at increased risk for impaired socio-emotional development. There is growing evidence that maltreated children may apprehend interpersonal encounters in different ways from children without such traumatic histories. This systematic review…

  18. Understanding Student Experiences: A Case Study in Scientific Visualization and Civics and Economics

    ERIC Educational Resources Information Center

    Jessee, Emily George

    2012-01-01

    This research study provides the finding of a qualitative case study in Technology, Engineering, and Design Education as well as Social Studies Education. The purpose of this study was to describe the role of graphics within a social studies lesson by examining a student's experience when a new lesson is implemented in class. The participants were…

  19. Employability and Higher Education: Contextualising Female Students' Workplace Experiences to Enhance Understanding of Employability Development

    ERIC Educational Resources Information Center

    Gracia, Louise

    2009-01-01

    Current political and economic discourses position employability as a responsibility of higher education, which deploys mechanisms such as supervised work experience (SWE) to embed employability skills development into the undergraduate curriculum. However, workplaces are socially constructed complex arenas of embodied knowledge that are gendered.…

  20. The Voices behind the Numbers: Understanding the Experiences of Homeless Students

    ERIC Educational Resources Information Center

    Mohan, Erica; Shields, Carolyn M.

    2014-01-01

    In a given year, approximately 1.6 million children in the United States experience homelessness, and research shows that their living conditions generally place these children at risk for educational underperformance and failure at school (Hall, 2007; Love, 2009). Although lack of education or low levels of education on the part of a head of…

  1. Understanding the Experiences of Latina/o Students: A Qualitative Study for Change

    ERIC Educational Resources Information Center

    Cavazos, Alyssa G.; Cavazos, Javier, Jr.

    2010-01-01

    A qualitative study with nine Latina/o college students was conducted to determine their experiences with their high school teachers. After careful data analysis, the following themes emerged: (a) some Latina/o students receive high expectations and others receive low expectations, (b) low expectations for non-AP students exist, and (c) some…

  2. Learning English in the Shadows: Understanding Chinese Learners' Experiences of Private Tutoring

    ERIC Educational Resources Information Center

    Yung, Kevin Wai-Ho

    2015-01-01

    Given that private tutoring has received increasing attention in research as a global educational phenomenon with significant implications for educational practices, it has become necessary for TESOL researchers and practitioners to become aware of its impact on language learning and pedagogy. This study investigated the learning experience and…

  3. Picturing Leisure: Using Photovoice to Understand the Experience of Leisure and Dementia

    ERIC Educational Resources Information Center

    Genoe, M. Rebecca; Dupuis, Sherry L.

    2013-01-01

    Interviews and participant observation are commonly used to explore the experience of dementia, yet may not adequately capture perspectives of persons with dementia as communication changes. We used photovoice (i.e., using cameras in qualitative research) along with interviews and participant observation to explore meanings of leisure for persons…

  4. Understanding Statin Non-Adherence: Knowing Which Perceptions and Experiences Matter to Different Patients

    PubMed Central

    Wouters, Hans; Van Dijk, Liset; Geers, Harm C. J.; Winters, Nina A.; Van Geffen, Erica C. G.; Stiggelbout, Anne M.; Bouvy, Marcel L.

    2016-01-01

    Background Non-adherence to statins is substantial and is associated with numerous perceptions and experiences. However, time limits in clinical practice constrain in depth explorations of these perceptions and experiences. Objectives To propose and examine a strategy aimed at an efficient assessment of a wide array of perceptions and experiences regarding the efficacy, side effects, and practical problems of statins. Furthermore, to assess associations between this wide array of experiences and perceptions and non-adherence and to examine whether patients' 'perceived self-efficacy' moderated these associations. Methods Patients were recruited through community pharmacies. A wide array of specific patient perceptions and experiences was efficiently assessed using the electronic Tailored Medicine Inventory that allows people to skip irrelevant questions. Adherence was measured through self-report and pharmacy refill data. Results Of the two-hundred twenty-nine patients who participated (mean age 63.9, standard deviation 10.2), 40%-70% doubted the necessity of or lacked knowledge about the efficacy of statins, 20%-35% of the patients were worried about joint and muscle side effects or had experienced these, and 23% had encountered practical problems regarding information about statins, intake of tablets, the package, or the blister. Experiencing more practical problems was associated with increased unintentional non-adherence (Odds ratio 1.54, 95%CI:1.13–2.10, P < 0.01), whereas worrying about side effects was associated with increased intentional non-adherence (Odds ratio 1.90, 95%CI:1.17–3.08, P < 0.01). Higher 'perceived self-efficacy' did not moderate these associations. Conclusions Insight into patients' specific barriers with regard to appropriate statin use may reveal personal reasons for being non-adherent. The Tailored Medicine Inventory is a promising tool to devise individualized intervention strategies aimed at improving adherence by the clinician

  5. Postmodernism in marriage and family therapy training: doctoral students' understanding and experiences.

    PubMed

    Wieling, E; Negretti, M A; Stokes, S; Kimball, T; Christensen, F B; Bryan, L

    2001-10-01

    The purpose of this study is to advance our understanding of how doctoral students perceive postmodernism's influence in the field of Marriage and Family Therapy (MFT). According to the literature, postmodernism has had a profound impact on many fields, including MFT. However, tracking of how postmodernism is actually being rendered in theory, research, practice, and training warrants investigation. This study utilized focus group interviews to investigate the perceptions of MFT doctoral students. Findings suggest that while participants are attracted to postmodern tenets, they also report feeling a mixture of liberation and excitement with confusion and fear regarding how postmodernism is influencing MFT models of therapy.

  6. Living through a volcanic eruption: Understanding the experience of survivors as a phenomenological existential phenomenon.

    PubMed

    Warsini, Sri; Mills, Jane; West, Caryn; Usher, Kim

    2016-06-01

    Mount Merapi in Indonesia is the most active volcano in the world with its 4-6-year eruption cycle. The mountain and surrounding areas are populated by hundreds of thousands of people who live near the volcano despite the danger posed to their wellbeing. The aim of this study was to explore the lived experience of people who survived the most recent eruption of Mount Merapi, which took place in 2010. Investigators conducted interviews with 20 participants to generate textual data that were coded and themed. Three themes linked to the phenomenological existential experience (temporality and relationality) of living through a volcanic eruption emerged from the data. These themes were: connectivity, disconnection and reconnection. Results indicate that the close relationship individuals have with Mount Merapi and others in their neighbourhood outweighs the risk of living in the shadow of an active volcano. This is the first study to analyze the phenomenological existential elements of living through a volcanic eruption.

  7. Ups and downs of the expatriate experience? Understanding work adjustment trajectories and career outcomes.

    PubMed

    Zhu, Jing; Wanberg, Connie R; Harrison, David A; Diehn, Erica W

    2016-04-01

    We examine changes in work adjustment among 179 expatriates from 3 multinational organizations from predeparture through the first 9 months of a new international assignment. Our 10-wave results challenge classic U-shaped theories of expatriate adjustment (e.g., Torbiorn, 1982). Consistent with uncertainty reduction theory, our results instead suggest that expatriates typically experience a gradual increase in work adjustment over time. Two resources that expatriates bring to their assignments (previous culture-specific work experience and core self-evaluations) moderate the trajectory of work adjustment. Trajectory of adjustment predicts Month 9 career instrumentality and turnover intention, as well as career advancement (job promotion) 1.5 years further. Implications for theory, as well as for changes in expatriate management practices, are discussed.

  8. Mapping the urban asthma experience: Using qualitative GIS to understand contextual factors affecting asthma control.

    PubMed

    Keddem, Shimrit; Barg, Frances K; Glanz, Karen; Jackson, Tara; Green, Sarah; George, Maureen

    2015-09-01

    Asthma is complex and connected to a number of factors including access to healthcare, crime and violence, and environmental triggers. A mixed method approach was used to examine the experiences of urban people with asthma in controlling their asthma symptoms. The study started with an initial phase of qualitative interviews in West Philadelphia, a primarily poor African American community. Data from qualitative, semi-structured interviews indicated that stress, environmental irritants, and environmental allergens were the most salient triggers of asthma. Based on the interviews, the team identified six neighborhood factors to map including crime, housing vacancy, illegal dumping, tree canopy and parks. These map layers were combined into a final composite map. These combined methodologies contextualized respondents' perceptions in the framework of the actual community and built environment which tells a more complete story about their experience with asthma.

  9. Contribution of gallium experiments to the understanding of solar physics and neutrino physics

    SciTech Connect

    Gavrin, V. N.

    2013-10-15

    The results of gallium measurements of solar neutrino and measurements with artificial sources of neutrinos are presented. Conclusions are drawn from these results, and the potential of the SAGE experiment for studying transitions of active neutrinos to sterile states for {Delta}m{sup 2} > 0.5 eV{sup 2} and a sensitivity of a few percent to the disappearance of electron neutrinos is examined.

  10. 'I sang Amazing Grace for about 3 hours that day': understanding Indigenous Australians' experience of seclusion.

    PubMed

    Sambrano, Rachel; Cox, Leonie

    2013-12-01

    Research shows that Indigenous Australians' suspicion and fear of being 'locked up' may influence mental health service avoidance. Given this, the aim of this study was to explore, by qualitative analysis of in-depth interviews (n = 3), how three Indigenous people experienced the controversial practice of seclusion. Hans-Georg Gadamer's phenomenology guided analysis of the material, and allowed narrated experiences to be understood within their cultural and historical context. Participants viewed seclusion negatively: police involvement in psychiatric care; perceptions of being punished and powerless; occasions of extreme use of force; and lack of care were prominent themes throughout the interviews. While power imbalances inherent in seclusion are problematic for all mental health clients, the distinguishing factor in the Indigenous clients' experience is that seclusion is continuous with the discriminatory and degrading treatment by governments, police, and health services that many Indigenous people have experienced since colonization. The participants' experiences echoed Goffman's findings that institutional practices act to degrade and dehumanize clients whose resulting conformity eases the work of nursing staff. While some nurses perceive that seclusion reduces clients' agitation, one must ask at what cost to clients' dignity, humanity, and basic human rights.

  11. Enactive cinema paves way for understanding complex real-time social interaction in neuroimaging experiments.

    PubMed

    Tikka, Pia; Väljamäe, Aleksander; de Borst, Aline W; Pugliese, Roberto; Ravaja, Niklas; Kaipainen, Mauri; Takala, Tapio

    2012-01-01

    We outline general theoretical and practical implications of what we promote as enactive cinema for the neuroscientific study of online socio-emotional interaction. In a real-time functional magnetic resonance imaging (rt-fMRI) setting, participants are immersed in cinematic experiences that simulate social situations. While viewing, their physiological reactions-including brain responses-are tracked, representing implicit and unconscious experiences of the on-going social situations. These reactions, in turn, are analyzed in real-time and fed back to modify the cinematic sequences they are viewing while being scanned. Due to the engaging cinematic content, the proposed setting focuses on living-by in terms of shared psycho-physiological epiphenomena of experience rather than active coping in terms of goal-oriented motor actions. It constitutes a means to parametrically modify stimuli that depict social situations and their broader environmental contexts. As an alternative to studying the variation of brain responses as a function of a priori fixed stimuli, this method can be applied to survey the range of stimuli that evoke similar responses across participants at particular brain regions of interest.

  12. Understanding In-line Probing Experiments by Modeling Cleavage of Non-reactive RNA Nucleotides.

    PubMed

    Mlynsky, Vojtech; Bussi, Giovanni

    2017-02-15

    Ribonucleic acid (RNA) is involved in many regulatory and catalytic processes in the cell. The function of any RNA molecule is intimately related with its structure. In-line probing experiments provide valuable structural datasets for a variety of RNAs and are used to characterize conformational changes in riboswitches. However, the structural determinants that lead to differential reactivities in unpaired nucleotides have not been investigated yet. In this work we used a combination of theoretical approaches, i.e., classical molecular dynamics simulations, multiscale quantum mechanical/molecular mechanical calculations, and enhanced sampling techniques in order to compute and interpret the differential reactivity of individual residues in several RNA motifs including members of the most important GNRA and UNCG tetraloop families. Simulations on the multi ns timescale are required to converge the related free-energy landscapes. The results for uGAAAg and cUUCGg tetraloops and double helices are compared with available data from in-line probing experiments and show that the introduced technique is able to distinguish between nucleotides of the uGAAAg tetraloop based on their structural predispositions towards phosphodiester backbone cleavage. For the cUUCGg tetraloop, more advanced ab initio calculations would be required. This study is the first attempt to computationally classify chemical probing experiments and paves the way for an identification of tertiary structures based on the measured reactivity of non-reactive nucleotides.

  13. Understanding reliance on automation: effects of error type, error distribution, age and experience

    PubMed Central

    Sanchez, Julian; Rogers, Wendy A.; Fisk, Arthur D.; Rovira, Ericka

    2015-01-01

    An obstacle detection task supported by “imperfect” automation was used with the goal of understanding the effects of automation error types and age on automation reliance. Sixty younger and sixty older adults interacted with a multi-task simulation of an agricultural vehicle (i.e. a virtual harvesting combine). The simulator included an obstacle detection task and a fully manual tracking task. A micro-level analysis provided insight into the way reliance patterns change over time. The results indicated that there are distinct patterns of reliance that develop as a function of error type. A prevalence of automation false alarms led participants to under-rely on the automation during alarm states while over relying on it during non-alarms states. Conversely, a prevalence of automation misses led participants to over-rely on automated alarms and under-rely on the automation during non-alarm states. Older adults adjusted their behavior according to the characteristics of the automation similarly to younger adults, although it took them longer to do so. The results of this study suggest the relationship between automation reliability and reliance depends on the prevalence of specific errors and on the state of the system. Understanding the effects of automation detection criterion settings on human-automation interaction can help designers of automated systems make predictions about human behavior and system performance as a function of the characteristics of the automation. PMID:25642142

  14. Understanding of emotional experience in autism: insights from the personal accounts of high-functioning children with autism.

    PubMed

    Losh, Molly; Capps, Lisa

    2006-09-01

    In this study, the authors investigate emotional understanding in autism through a discourse analytic framework to provide a window into children's strategies for interpreting emotional versus nonemotional encounters and consider the implications for the mechanisms underlying emotional understanding in typical development. Accounts were analyzed for thematic content and discourse structure. Whereas high-functioning children with autism were able to discuss contextually appropriate accounts of simple emotions, their strategies for interpreting all types of emotional (but not nonemotional) experiences differed from those used by typically developing children. High-functioning children with autism were less inclined to organize their emotional accounts in personalized causal-explanatory frameworks and displayed a tendency to describe visually salient elements of experiences seldom observed among comparison children. Findings suggest that children with autism possess less coherent representations of emotional experiences and use alternative strategies for interpreting emotionally evocative encounters. Discussion focuses on the significance of these findings for informing the nature of emotional dysfunction in autism as well as implications for theories of emotional understanding in typical development.

  15. What happens after diagnosis? Understanding the experiences of patients with newly‐diagnosed bipolar disorder

    PubMed Central

    Proudfoot, Judith G; Parker, Gordon B; Benoit, Megan; Manicavasagar, Vijaya; Smith, Meg; Gayed, Aimee

    2009-01-01

    Abstract Bipolar disorder is chronic condition involving episodes of both depression and elevated mood, associated with significant disability and high relapse rates. Recent estimates suggest a lifetime prevalence of 5%. Little is known about the subjective experiences of patients after receiving a diagnosis of bipolar disorder, and the impact of these experiences on patients' willingness and ability to work with their health professionals to find the most effective combination of treatments and to set up self‐management plans. Objective  This paper describes a qualitative study exploring the experiences and difficulties faced by patients after they have received a diagnosis of bipolar disorder, as expressed online to expert patients trained to provide informed support. Design  Qualitative study. Setting  Online communication within a public health service setting. Participants  Twenty‐six participants with recently‐diagnosed bipolar disorder communicated online with ‘Informed Supporters’, people who had been managing their bipolar disorder effectively for 2 years or more, as part of an online psycho‐education programme. Results  Participants cited unwanted side‐effects of medication, coping with unpleasant symptoms, positive and negative reactions to the diagnosis, identifying early warning signs and triggers of the illness, the loss of a sense of self, uncertainty about their future and stigma as issues of major importance after diagnosis. Conclusions  Personal concerns and difficulties following diagnosis can undermine effective treatment, thwart self‐management efforts and interfere with effective functioning. Such data are important for clinicians to take into account when they work in partnership with their patients to fine‐tune treatments and help them set up self‐management plans. PMID:19538647

  16. Understanding fuel anti-knock performances in modern SI engines using fundamental HCCI experiments

    SciTech Connect

    Yang, Yi; Dec, John E.; Sjoberg, Magnus; Ji, Chunsheng

    2015-08-19

    Modern spark-ignition (SI) engine technologies have considerably changed in-cylinder conditions under which fuel autoignition and engine knock take place. In this paper, fundamental HCCI engine experiments are proposed as a means for characterizing the impact of these technologies on the knock propensity of different fuels. In particular, the impacts of turbocharging, direct injection (DI), and downspeeding on operation with ethanol and gasoline are investigated to demonstrate this approach. Results reported earlier for ethanol and gasoline on HCCI combustion are revisited with the new perspective of how their autoignition characteristics fit into the anti-knock requirement in modern SI engines. For example, the weak sensitivity to pressure boost demonstrated by ethanol in HCCI autoignition can be used to explain the strong knock resistance of ethanol fuels for turbocharged SI engines. Further, ethanol's high sensitivity to charge temperature makes charge cooling, which can be produced by fuel vaporization via direct injection or by piston expansion via spark-timing retard, very effective for inhibiting knock. On the other hand, gasoline autoignition shows a higher sensitivity to pressure, so only very low pressure boost can be applied before knock occurs. Gasoline also demonstrates low temperature sensitivity, so it is unable to make as effective use of the charge cooling produced by fuel vaporization or spark retard. These arguments comprehensively explain literature results on ethanol's substantially better anti-knock performance over gasoline in modern turbocharged DISI engines. Fundamental HCCI experiments such as these can thus be used as a diagnostic and predictive tool for knock-limited SI engine performance for various fuels. As a result, examples are presented where HCCI experiments are used to identify biofuel compounds with good potential for modern SI-engine applications.

  17. Understanding fuel anti-knock performances in modern SI engines using fundamental HCCI experiments

    DOE PAGES

    Yang, Yi; Dec, John E.; Sjoberg, Magnus; ...

    2015-08-19

    Modern spark-ignition (SI) engine technologies have considerably changed in-cylinder conditions under which fuel autoignition and engine knock take place. In this paper, fundamental HCCI engine experiments are proposed as a means for characterizing the impact of these technologies on the knock propensity of different fuels. In particular, the impacts of turbocharging, direct injection (DI), and downspeeding on operation with ethanol and gasoline are investigated to demonstrate this approach. Results reported earlier for ethanol and gasoline on HCCI combustion are revisited with the new perspective of how their autoignition characteristics fit into the anti-knock requirement in modern SI engines. For example,more » the weak sensitivity to pressure boost demonstrated by ethanol in HCCI autoignition can be used to explain the strong knock resistance of ethanol fuels for turbocharged SI engines. Further, ethanol's high sensitivity to charge temperature makes charge cooling, which can be produced by fuel vaporization via direct injection or by piston expansion via spark-timing retard, very effective for inhibiting knock. On the other hand, gasoline autoignition shows a higher sensitivity to pressure, so only very low pressure boost can be applied before knock occurs. Gasoline also demonstrates low temperature sensitivity, so it is unable to make as effective use of the charge cooling produced by fuel vaporization or spark retard. These arguments comprehensively explain literature results on ethanol's substantially better anti-knock performance over gasoline in modern turbocharged DISI engines. Fundamental HCCI experiments such as these can thus be used as a diagnostic and predictive tool for knock-limited SI engine performance for various fuels. As a result, examples are presented where HCCI experiments are used to identify biofuel compounds with good potential for modern SI-engine applications.« less

  18. Understanding the life experience of people on hemodialysis: adherence to treatment and quality of life.

    PubMed

    Guerra-Guerrerro, Verónica; Plazas, Maria del Pilar Camargo; Cameron, Brenda L; Salas, Anna Valeria Santos; González, Carmen Gloria Cofre

    2014-01-01

    This hermeneutic-phenomenological study explores the lived experiences of patients on hemodialysis in regard to the adherence to treatment and quality of life. Fifteen patients were interviewed, including six women and nine men from three dialysis centers in Chile. Two main themes derived from the analysis: 1) embracing the disease and dialysis, and 2) preventing progression of the disease through treatment management. The findings suggest that patients recognize adherence to treatment and quality of life as conditions that derive from self-care and environmental conditions, which the healthcare provider must constantly assess for care planning to improve the adherence and quality of life in this population.

  19. INCREASED UNDERSTANDING OF BEAM LOSSES FROM THE SNS LINAC PROTON EXPERIMENT

    SciTech Connect

    Aleksandrov, Alexander V; Shishlo, Andrei P; Plum, Michael A; Lebedev, Valerie; Laface, Emanuele; Galambos, John D

    2013-01-01

    Beam loss is a major concern for high power hadron accelerators such as the Spallation Neutron Source (SNS). An unexpected beam loss in the SNS superconducting linac (SCL) was observed during the power ramp up and early operation. Intra-beam-stripping (IBS) loss, in which interactions between H- particles within the accelerated bunch strip the outermost electron, was recently identified as a possible cause of the beam loss. A set of experiments using proton beam acceleration in the SNS linac was conducted, which supports IBS as the primary beam loss mechanism in the SNS SCL.

  20. Bringing first-hand experience one step closer to theoretical understanding

    NASA Astrophysics Data System (ADS)

    Luo, Haoxiang; Myers, Mike; Luo's lab Team

    2016-11-01

    Many theoretical concepts and analytical approaches in fluid mechanics are challenging to teach. Classroom demos are very useful to engage and motivate students, but they do not necessarily lead straightforwardly to higher level understanding of model abstraction that is expressed with mathematical equations. To facilitate the process, we have designed a few demos and integrated them with quantitative measurements and theoretical analysis. These demos, usually generated from daily life examples, are of low cost and simple to implement, and the experimental procedures do not take significant time in a 50-min lecture. When combining them with classroom interactions, problem solving, and discussions, we found that these modules are effective in helping students in the learning process. Supported by the NSF.

  1. From necessity to sufficiency in memory research: when sleep helps to understand wake experiences.

    PubMed

    Lacroix, Marie Masako; De Lavilléon, Gaetan; Benchenane, Karim

    2015-12-01

    Memory is the ability to adapt our behavior by using the stored information, previously encoded. The first investigations of the neuronal bases of the memory trace concerned its properties (location, cellular and molecular mechanisms, among others). However, to understand how this is achieved at the scale of neurons, we must provide evidence about the necessity of a neuronal subpopulation to support the memory trace, but also its sufficiency. Here, we will present past and recent studies that provide information about the neuronal nature of memories. We will show that research on sleep, when cells assembly supposedly carrying information from the past are replayed, could also provide valuable information about the memory processes at stake during wake.

  2. The role of social marketing in understanding access to primary health care services: perceptions and experiences.

    PubMed

    Akinci, Fevzi; Healey, Bernard J

    2004-01-01

    Using the concept of social marketing, this study examined the determinants of access to primary health care services in order to better understand the perceived access problems and unmet service needs of an entire city in Northeastern Pennsylvania. Consistent with previous research, lack of access to health insurance coverage represents an important financial barrier to access to health care services in this community. This study also highlights the role of perceived need in explaining the presence or absence of a physician consultation.While increased attention to access issues at the national level is important, there also needs to be more emphasis on collecting local data for local decision-making regarding access issues.

  3. Field experiments of Controlled Drainage of agricultural clay soils show positive effects on water quantity (retention, runoff) and water quality (nitrate leaching).

    NASA Astrophysics Data System (ADS)

    schipper, peter; stuyt, lodewijk; straat, van der, andre; schans, van der, martin

    2014-05-01

    processes in the soil have been modelled with simulation model SWAP. The experiment started in 2010 and is ongoing. Data, collected so far show that the plots with controlled drainage (all compared with plots equipped with conventional drainage) conserve more rain water (higher groundwater tables in early spring), lower discharges under average weather conditions and storm events, reduce N-loads and saline seepage to surface waters, enhance denitrification, show a different 'first flush' effect and show similar crop yields. The results of the experiments will contribute to a better understanding of the impact of controlled drainage on complex hydrological en geochemical processes in agricultural clay soils, the interaction between ground- en surface water and its effects on drain water quantity, quality and crop yield.

  4. Humanoid infers Archimedes' principle: understanding physical relations and object affordances through cumulative learning experiences

    PubMed Central

    2016-01-01

    Emerging studies indicate that several species such as corvids, apes and children solve ‘The Crow and the Pitcher’ task (from Aesop's Fables) in diverse conditions. Hidden beneath this fascinating paradigm is a fundamental question: by cumulatively interacting with different objects, how can an agent abstract the underlying cause–effect relations to predict and creatively exploit potential affordances of novel objects in the context of sought goals? Re-enacting this Aesop's Fable task on a humanoid within an open-ended ‘learning–prediction–abstraction’ loop, we address this problem and (i) present a brain-guided neural framework that emulates rapid one-shot encoding of ongoing experiences into a long-term memory and (ii) propose four task-agnostic learning rules (elimination, growth, uncertainty and status quo) that correlate predictions from remembered past experiences with the unfolding present situation to gradually abstract the underlying causal relations. Driven by the proposed architecture, the ensuing robot behaviours illustrated causal learning and anticipation similar to natural agents. Results further demonstrate that by cumulatively interacting with few objects, the predictions of the robot in case of novel objects converge close to the physical law, i.e. the Archimedes principle: this being independent of both the objects explored during learning and the order of their cumulative exploration. PMID:27466440

  5. Humanoid infers Archimedes' principle: understanding physical relations and object affordances through cumulative learning experiences.

    PubMed

    Bhat, Ajaz Ahmad; Mohan, Vishwanathan; Sandini, Giulio; Morasso, Pietro

    2016-07-01

    Emerging studies indicate that several species such as corvids, apes and children solve 'The Crow and the Pitcher' task (from Aesop's Fables) in diverse conditions. Hidden beneath this fascinating paradigm is a fundamental question: by cumulatively interacting with different objects, how can an agent abstract the underlying cause-effect relations to predict and creatively exploit potential affordances of novel objects in the context of sought goals? Re-enacting this Aesop's Fable task on a humanoid within an open-ended 'learning-prediction-abstraction' loop, we address this problem and (i) present a brain-guided neural framework that emulates rapid one-shot encoding of ongoing experiences into a long-term memory and (ii) propose four task-agnostic learning rules (elimination, growth, uncertainty and status quo) that correlate predictions from remembered past experiences with the unfolding present situation to gradually abstract the underlying causal relations. Driven by the proposed architecture, the ensuing robot behaviours illustrated causal learning and anticipation similar to natural agents. Results further demonstrate that by cumulatively interacting with few objects, the predictions of the robot in case of novel objects converge close to the physical law, i.e. the Archimedes principle: this being independent of both the objects explored during learning and the order of their cumulative exploration.

  6. Laser scanning confocal microscopy and laser tweezers based experiments to understand dentine-bacteria interactions

    NASA Astrophysics Data System (ADS)

    Peng, Sum Chee; Mohanty, Samarendra; Gupta, P. K.; Kishen, Anil

    2007-02-01

    Failure of endodontic treatment is commonly due to Enterococcal infection. In this study influence of chemical treatments of type-I collagen membrane by chemical agents commonly used in endodontic treatment on Enterococcus faecalis cell adherence was evaluated. In order to determine the change in number of adhering bacteria after chemical treatment, confocal laser scanning microscopy was used. For this, overnight culture of E faecalis in All Culture broth was applied to chemically treated type-I collagen membrane. It was found that Ca(OH) II treated groups had statistically significant (p value=0.05) increase in population of bacteria adherence. The change in adhesion force between bacteria and collagen was determined by using optical tweezers (1064 nm). For this experiment, Type-I collagen membrane was soaked for 5 mins in a media that contained 50% all culture media and 50% saturated Ca(OH) II . The membrane was spread on the coverslip, on which diluted bacterial suspension was added. The force of laser tweezers on the bacteria was estimated at different trap power levels using viscous drag method and trapping stiffness was calculated using Equipartition theorem method. Presence of Ca(OH) II was found to increase the cell-substrate adherence force from 0.38pN to >2.1pN. Together, these experiments show that it was highly probable that the increase in adherence to collagen was due to a stronger adhesion in the presence of Ca (OH) II.

  7. Understanding women's experiences of distress during pregnancy in Dar es Salaam, Tanzania.

    PubMed

    Kaaya, S F; Mbwambo, J K; Fawzi, M C Smith; Van Den Borne, H; Schaalma, H; Leshabari, M T

    2010-01-01

    Several studies show depression is common during pregnancy. However, there is limited information in Tanzania on the magnitude of perceived distress during pregnancy and meanings ascribed to such distress. A descriptive survey collected data using unstructured interviews from 12 traditional practitioners and 10 peri-urban women with previous pregnancy related mental health concerns identified using a depression vignette. The objectives were to describe the sources and characteristics of distress during pregnancy, and idioms of distress that could inform cultural adaptation of depression screening tools. Narrative analysis showed an emergent category of "problematic pregnancies" framed women's recollections of prolonged periods of sadness. This experience was qualified using various idioms of distress that were differentially emphasized depending on informant's perceived causes of health concern. The idiom kusononeka was consistently used to describe extreme sadness across causal categories and clustered with at least two typical features of major depression. This suggested existence of a construct with similarities to biomedical criteria for depression. "Thinking too much" emerged as a distinctive expression associated with prolonged sadness. Distinctive expressions of social functioning impairments were identified that can inform depression severity assessments. In conclusion, contextual inquiry into experiences of psychological distress showed distinct local idioms that clustered in patterns similar to symptoms of biomedical depressive episodes. Further studies to assess the utility of local idioms of distress and distress related functional impairment in depression assessment tools are warranted.

  8. Seasonal variation and homes: understanding the social experiences of older adults.

    PubMed

    Perry, Tam E

    2014-01-01

    There has been limited research on the importance of seasons in the lives of older adults. Previous research has highlighted seasonal fluctuations in physical functioning--including limb strength, range of motion, and cardiac death--the spread of influenza in seasonal migration patterns. In addition, older adults experience isolation for various reasons, such as decline of physical and cognitive ability, lack of transportation, and lack of opportunities for social interaction. There has been much attention paid to the social isolation of older adults, yet little analysis about how the isolation changes throughout the year. Based on findings from an ethnographic study of older adults (n = 81), their family members (n = 49), and supportive professionals (n = 46) as they embark on relocation from their homes, this study analyzes the processes of moving for older adults. It examines the seasonal fluctuations of social isolation because of the effect of the environment on the social experiences of older adults. Isolation occurs because of the difficulty inclement weather causes on social interactions and mobility. The article concludes with discussion of the ways that research and practice can be designed and implemented to account for seasonal variation.

  9. Seasonal Variation and Homes: Understanding the Social Experiences of Older Adults

    PubMed Central

    Perry, Tam E.

    2014-01-01

    There has been limited research on the importance of seasons in the lives of older adults. Previous research has highlighted seasonal fluctuations in physical functioning—including limb strength, range of motion, and cardiac death—the spread of influenza in seasonal migration patterns. In addition, older adults experience isolation for various reasons, such as decline of physical and cognitive ability, lack of transportation, and lack of opportunities for social interaction. There has been much attention paid to the social isolation of older adults, yet little analysis about how the isolation changes throughout the year. Based on findings from an ethnographic study of older adults (n = 81), their family members (n = 49), and supportive professionals (n = 46) as they embark on relocation from their homes, this study analyzes the processes of moving for older adults. It examines the seasonal fluctuations of social isolation because of the effect of the environment on the social experiences of older adults. Isolation occurs because of the difficulty inclement weather causes on social interactions and mobility. The article concludes with discussion of the ways that research and practice can be designed and implemented to account for seasonal variation. PMID:24761536

  10. Understanding the Influence of Environment on Adults’ Walking Experiences: A Meta-Synthesis Study

    PubMed Central

    Dadpour, Sara; Pakzad, Jahanshah; Khankeh, Hamidreza

    2016-01-01

    The environment has an important impact on physical activity, especially walking. The relationship between the environment and walking is not the same as for other types of physical activity. This study seeks to comprehensively identify the environmental factors influencing walking and to show how those environmental factors impact on walking using the experiences of adults between the ages of 18 and 65. The current study is a meta-synthesis based on a systematic review. Seven databases of related disciplines were searched, including health, transportation, physical activity, architecture, and interdisciplinary databases. In addition to the databases, two journals were searched. Of the 11,777 papers identified, 10 met the eligibility criteria and quality for selection. Qualitative content analysis was used for analysis of the results. The four themes identified as influencing walking were “safety and security”, “environmental aesthetics”, “social relations”, and “convenience and efficiency”. “Convenience and efficiency” and “environmental aesthetics” could enhance the impact of “social relations” on walking in some aspects. In addition, “environmental aesthetics” and “social relations” could hinder the influence of “convenience and efficiency” on walking in some aspects. Given the results of the study, strategies are proposed to enhance the walking experience. PMID:27447660

  11. Anomalies in the applied magnetic fields in DIII-D and their implications for the understanding of stability experiments

    SciTech Connect

    Luxon, J. L.; Schaffer, M. J.; Jackson, G. L.; Leuer, J. A.; Nagy, A.; Scoville, J. T.; Strait, E. J.

    2003-12-01

    Small non-axisymmetric magnetic fields are known to cause serious loss of stability in tokamaks leading to loss of confinement and abrupt termination of plasma current (disruptions). The best known examples are the locked mode and the resistive wall mode. Understanding of the underlying field anomalies (departures in the hardware-related fields from ideal toroidal and poloidal fields on a single axis) and the interaction of the plasma with them is crucial to tokamak development. Results of both locked mode experiments and resistive wall mode experiments done in DIII-D tokamak plasmas have been interpreted to indicate the presence of a significant anomalous field. New measurements of the magnetic field anomalies of the hardware systems have been made on DIII-D. The measured field anomalies due to the plasma shaping coils in DIII-D are smaller than previously reported. Additional evaluations of systematic errors have been made. New measurements of the anomalous fields of the ohmic heating and toroidal coils have been added. Such detailed in situ measurements of the fields of a tokamak are unique. The anomalous fields from all of the coils are one third of the values indicated from the stability experiments. These results indicate limitations in the understanding of the interaction of the plasma with the external field. They indicate that it may not be possible to deduce the anomalous fields in a tokamak from plasma experiments and that we may not have the basis needed to project the error field requirements of future tokamaks.

  12. Understanding the implications of the data from recent high-energy-density Kelvin-Helmholtz shear layer experiments

    SciTech Connect

    Hurricane, O A; Hansen, J F; Harding, E C; Drake, R P; Robey, H F; Remington, B A; Kuranz, C C; Grosskopf, M J; Gillespie, R S; Park, H

    2009-10-26

    The first successful high energy density Kelvin-Helmholtz (KH) shear layer experiments (O.A. Hurricane, et al., Phys. Plasmas, 16, 056305, 2009; E.C. Harding, et al., Phys. Rev. Lett., 103, 045005, 2009) demonstrated the ability to design and field a target that produces an array of large diagnosable KH vortices in a controlled fashion. Data from these experiments vividly showed the complete evolution of large distinct eddies, from formation to apparent turbulent break-up. Unexpectedly, low-density bubbles/cavities comparable to the vortex size ({approx} 300 - 400 {micro}m) appeared to grow up in the free-stream flow above the unstable material interface. In this paper, the basic principles of the experiment will be discussed, the data reviewed, and the progress on understanding the origin of the above bubble structures through theory and simulation will be reported on.

  13. Understanding the experience of place: Expanding methods to conceptualize and measure community integration of persons with serious mental illness

    PubMed Central

    Townley, Greg; Kloos, Bret; Wright, Patricia A.

    2008-01-01

    Community integration research explores community contexts and factors that encourage or hinder individuals with serious mental illness (SMI) from actively participating in community life. This research agenda can be advanced by using mixed-methods that better document the relationships between contextual factors and individual experience. Two such methods were applied to a mixed-methods study of 40 adults with SMI living in independent housing in the Southeastern United States. Their contextualized experiences of community integration were measured by applying innovative participatory mapping and Geographic Information Systems (GIS) mapping techniques. Use of these methods in conjunction with one another facilitated the creation of activity spaces, which can measure geographic accessibility and help to represent an individual's experience of place and degree of mobility. The utility of these newly applied methods for better understanding community integration for persons with SMI is explored and implications for using these measures in research and practice are discussed. PMID:19062326

  14. Understanding Hong Kong Chinese Families' Experiences of an Autism/ASD Diagnosis.

    PubMed

    Tait, Kathleen; Fung, Francis; Hu, Aihua; Sweller, Naomi; Wang, Wei

    2016-04-01

    Little is known about the experience of Chinese parents of children diagnosed with autism spectrum disorders (ASD) living in the Hong Kong Special Administrative Region. Seventy-five parents of children (aged 6 months-18 years) with ASD diagnoses completed the Family Quality of Life Scale. Forty-five parents from the original surveyed cohort, also participated in semi-structured interviews. Parents' perceptions of their child's disability were influenced both by their cultural background and by the limited and expensive, pre- and post-diagnostic services available. Longer waiting times to diagnosis were associated with lower emotional well-being and perceived disability-related support. Clinicians are encouraged to become part of the support network for parents of children with ASD, to help parents to adjust to caring for their child.

  15. Understanding the Decisions and Values of Stakeholders in Health Information Exchanges: Experiences From Massachusetts

    PubMed Central

    Simon, Steven R.; Volk, Lynn A.; Tripathi, Micky; Bates, David

    2009-01-01

    Objectives. We studied how health information exchange systems are established by examining the decisions (and thus, indirectly, the values) of key stakeholders (health care providers) participating in a health information exchange pilot project in 3 Massachusetts communities. Our aim was to understand how these kinds of information exchanges can be made viable. Methods. We used semistructured interviews to assess health care providers' decision-making processes in selecting technical architectures and vendors for the pilot projects to uncover their needs, expectations, and motivations. Results. Our interviews indicated that, after extensive evaluations, health care providers in all 3 communities eventually selected a hybrid architecture that included a central data repository. However, the reasons for selecting this architecture varied considerably among the 3 communities, reflecting their particular values. Plans to create a community patient portal also differed across communities. Conclusions. Our findings suggest that, to become established, health information exchange efforts must foster trust, appeal to strategic interests of the medical community as a whole, and meet stakeholder expectations of benefits from quality measurements and population health interventions. If health information exchange organizations cannot address these factors, sustainability will remain precarious. PMID:19299671

  16. Complex emotions, complex problems: understanding the experiences of perinatal depression among new mothers in urban Indonesia.

    PubMed

    Andajani-Sutjahjo, Sari; Manderson, Lenore; Astbury, Jill

    2007-03-01

    In this article, we explore how Javanese women identify and speak of symptoms of depression in late pregnancy and early postpartum and describe their subjective accounts of mood disorders. The study, conducted in the East Java region of Indonesia in 2000, involved in-depth interviews with a subgroup of women (N = 41) who scored above the cutoff score of 12/13 on the Edinburgh Postnatal Depression Scale (EPDS) during pregnancy, at six weeks postpartum, or on both occasions. This sample was taken from a larger cohort study (N cohort = 488) researching the sociocultural factors that contribute to women's emotional well-being in early motherhood. The women used a variety of Indonesian and Javanese terms to explain their emotional states during pregnancy and in early postpartum, some of which coincided with the feelings described on the EPDS and others of which did not. Women attributed their mood variations to multiple causes including: premarital pregnancy, chronic illness in the family, marital problems, lack of support from partners or family networks, their husband's unemployment, and insufficient family income due to giving up their own paid work. We argue for the importance of understanding the context of childbearing in order to interpret the meaning of depression within complex social, cultural, and economic contexts.

  17. Do Signers Understand Regional Varieties of a Sign Language? A Lexical Recognition Experiment.

    PubMed

    Stamp, Rose

    2016-01-01

    The degree of mutual intelligibility of British Sign Language (BSL) regional varieties has been a subject of some debate. Recent research in which dyads of signers from contrasting regional backgrounds engaged in a conversational task showed no problems understanding one another. The present study investigated signers' knowledge of different BSL regional varieties. Twenty-five participants from Belfast, Glasgow, Manchester, and Newcastle took part in a computer-based lexical recognition task in which they had to identify the meaning of 47 color signs from various regions in the United Kingdom. The results indicate that overall signers have a poor knowledge of regional signs for colors when signs are presented in isolation and without mouthing. Furthermore, signers with deaf parents performed better in the recognition task than signers with hearing parents and varieties from London and Birmingham were easiest to recognize. This article discusses how signers cope with regional differences and considers the features that facilitate in the recognition of regional varieties in BSL.

  18. Individual differences in conceptual and procedural fraction understanding: the role of abilities and school experience.

    PubMed

    Hallett, Darcy; Nunes, Terezinha; Bryant, Peter; Thorpe, Christina M

    2012-12-01

    Recent research on children's conceptual and procedural knowledge has suggested that there are individual differences in the ways that children combine these two types of knowledge across a number of mathematical topics. Cluster analyses have demonstrated that some children have more conceptual knowledge, some children have more procedural knowledge, and some children have an equal level of both. The current study investigated whether similar individual differences exist in children's understanding of fractions and searches for explanations for these differences. Grade 6 students (n=119) and Grade 8 students (n=114) were given measures of conceptual and procedural knowledge of fractions as well as measures of general fraction knowledge, general conceptual ability, and general procedural ability. Grade 6 children demonstrated a four-cluster solution reflecting those who do poorly on procedural and conceptual fraction knowledge, those who do well on both, those whose strength is procedural knowledge, and those whose strength is conceptual knowledge. Grade 8 children demonstrated a two-cluster solution reflecting those whose strength is procedural knowledge and those whose strength is conceptual knowledge. Cluster in either grade, however, did not vary in distribution across schools and was not related to general conceptual ability or general procedural ability. Overall, these results provide a more detailed picture of individual differences in conceptual and procedural knowledge in mathematical cognition.

  19. Developing an in vitro understanding of patient experience with hydrofluoroalkane-metered dose inhalers.

    PubMed

    Doub, William H; Shah, Vibhakar; Limb, Susan; Guo, Changning; Liu, Xiaofei; Ngo, Diem

    2014-11-01

    As a result of the Montreal Protocol on Substances that Deplete the Ozone Layer, manufacturers of metered dose inhalers began reformulating their products to use hydrofluoroalkanes (HFAs) as propellants in place of chlorofluorocarbons (CFCs). Although the new products are considered safe and efficacious by the US Food and Drug Administration (FDA), a large number of complaints have been registered via the FDA's Adverse Events Reporting System (FAERS)-more than 7000 as of May 2013. To develop a better understanding of the measurable parameters that may, in part, determine in vitro performance and thus patient compliance, we compared several CFC- and HFA-based products with respect to their aerodynamic performance in response to changes in actuator cleaning interval and interactuation delay interval. Comparison metrics examined in this study were: total drug delivered ex-actuator, fine particle dose (<5 μm), mass median aerodynamic diameter, plume width, plume temperature, plume impaction force, and actuator orifice diameter. Overall, no single metric or test condition distinguishes HFA products from CFC products, but, for individual products tested, there were a combination of metrics that differentiated one from another.

  20. Understanding the mixing process in 3D microfluidic nozzle/diffuser systems: simulations and experiments

    NASA Astrophysics Data System (ADS)

    Sayah, Abdeljalil; Gijs, Martin A. M.

    2016-11-01

    We characterise computationally and experimentally a three-dimensional (3D) microfluidic passive mixer for various Reynolds numbers ranging from 1 to 100, corresponding to primary flow rates of 10-870 µl min-1. The 3D mixing channel is composed of multiple curved segments: circular arcs situated in the substrate plane and curved nozzle/diffuser elements normal to the substrate plane. Numerical simulation provides a detailed understanding of the mixing mechanism resulting from the geometrical topology of the mixer. These Comsol software-based simulations reveal the development of two secondary flows perpendicular to the primary flow: a swirling flow resulting from tangential injection of the flow into the nozzle holes and Dean vortices present in the circular arcs. These phenomena are particularly important at a Reynolds number larger than 30, where mixing occurs by chaotic advection. Experimentally, the 3D mixer is fabricated in a monolithic glass substrate by powder blasting machining, exploiting eroding powder beams at various angles of impact with respect to the substrate plane. Experimental mixing was characterised using two coloured dyes, showing nearly perfect mixing for a microfluidic footprint of the order of a few mm2, in good agreement with the simulations.

  1. Toward a deeper understanding of how experiments constrain the underlying physics of heavy-ion collisions

    NASA Astrophysics Data System (ADS)

    Sangaline, Evan; Pratt, Scott

    2016-02-01

    Recent work has provided the means to rigorously determine properties of superhadronic matter from experimental data through the application of broad scale modeling of high-energy nuclear collisions within a Bayesian framework. These studies have provided unprecedented statistical inferences about the physics underlying nuclear collisions by virtue of simultaneously considering a wide range of model parameters and experimental observables. Notably, this approach has been used to constrain both the QCD equation of state and the shear viscosity above the quark-hadron transition. Although the inferences themselves have a clear meaning, the complex nature of the relationships between model parameters and observables has remained relatively obscure. We present here a novel extension of the standard Bayesian Markov-chain Monte Carlo approach that allows for the quantitative determination of how inferences of model parameters are driven by experimental measurements and their uncertainties. This technique is then applied in the context of heavy-ion collisions in order to explore previous results in greater depth. The resulting relationships are useful for identifying model weaknesses, prioritizing future experimental measurements, and, most importantly, developing an intuition for the roles that different observables play in constraining our understanding of the underlying physics.

  2. Retention, retention, retention: targeting the young in CPR skills training!

    PubMed

    Roppolo, Lynn P; Pepe, Paul E

    2009-01-01

    The usefulness of basic cardiopulmonary resuscitation (CPR) training in school systems has been questioned, considering that young students may not have the physical or cognitive skills required to perform complex tasks correctly. In the study conducted by Fleishhackl and coworkers, students as young as 9 years were able to successfully and effectively learn basic CPR skills, including automated external defibrillator deployment, correct recovery position, and emergency calling. As in adults, physical strength may limit the depth of chest compressions and ventilation volumes given by younger individuals with low body mass index; however, skill retention is good. Training all persons across an entire community in CPR may have a logarithmic improvement in survival rates for out-of-hospital cardiac arrest because bystanders, usually family members, are more likely to know CPR and can perform it immediately, when it is physiologically most effective. Training captured audiences of trainees, such as the entire work-force of the community or the local school system, are excellent mechanisms to help achieve that goal. In addition to better retention with new half hour training kits, a multiplier effect can be achieved through school children. In addition, early training not only sets the stage for subsequent training and better retention, but it also reinforces the concept of a social obligation to help others.

  3. Understanding Crew Decision-Making in the Presence of Complexity: A Flight Simulation Experiment

    NASA Technical Reports Server (NTRS)

    Young, Steven D.; Daniels, Taumi S.; Evans, Emory; deHaag, Maarten Uijt; Duan, Pengfei

    2013-01-01

    Crew decision making and response have long been leading causal and contributing factors associated with aircraft accidents. Further, it is anticipated that future aircraft and operational environments will increase exposure to risks related to these factors if proactive steps are not taken to account for ever-increasing complexity. A flight simulation study was designed to collect data to help in understanding how complexity can, or may, be manifest. More specifically, an experimental apparatus was constructed that allowed for manipulation of information complexity and uncertainty, while also manipulating operational complexity and uncertainty. Through these manipulations, and the aid of experienced airline pilots, several issues have been discovered, related most prominently to the influence of information content, quality, and management. Flight crews were immersed in an environment that included new operational complexities suggested for the future air transportation system as well as new technological complexities (e.g. electronic flight bags, expanded data link services, synthetic and enhanced vision systems, and interval management automation). In addition, a set of off-nominal situations were emulated. These included, for example, adverse weather conditions, traffic deviations, equipment failures, poor data quality, communication errors, and unexpected clearances, or changes to flight plans. Each situation was based on one or more reference events from past accidents or incidents, or on a similar case that had been used in previous developmental tests or studies. Over the course of the study, 10 twopilot airline crews participated, completing over 230 flights. Each flight consisted of an approach beginning at 10,000 ft. Based on the recorded data and pilot and research observations, preliminary results are presented regarding decision-making issues in the presence of the operational and technological complexities encountered during the flights.

  4. Understanding performance and behavior of tightly coupled outpatient systems using RFID: initial experience.

    PubMed

    Stahl, James E; Holt, Julie K; Gagliano, Nancy J

    2011-06-01

    Understanding how clinical systems actually behave in an era of limited medical resources is critical. The purpose of this study was to determine if a radiofrequency-identification-based indoor positioning system (IPS) could objectively and unobtrusively capture outpatient clinic behavior. Primary outcomes were flowtime, wait time and patient/clinician face time. Two contrasting clinics were evaluated: a primary care clinic (PC) with templated scheduling and an urgent care clinic (UC) with unconstrained visit time and first-in, first-out scheduling. All staff wore transponders throughout the study period. Patients carried transponders from check in to check out. All patients and staff were allowed to opt out. The study was approved by hospital IRB. Standard descriptive and analytic statistical methods were used. Five hundred twenty-six patients (309 patients (PC), 217 patients (UC)) and 38 clinicians (eight (PC) and 30 (UC)) volunteered between April 30 and July 1, 2008. Total FT was not significantly different across clinics. PC wait time was significantly shorter (7.6 min [SD 15.8]) vs. UC (19.7 min [SD 25.3], p < 0.0001), and PC Face time was significantly longer (29.9 min, [SD 19.1] vs. UC (9.8 min [SD 8.5], p < 0.0001). PC Face time distributions reflected template scheduling structure. In contrast, face time distributions in UC had a smooth log normal distribution with a lower mean value. Our study seems to indicate that an IPS can successfully measure important clinic process measures in live clinical outpatient settings and capture behavioral differences across different outpatient organizational structures.

  5. Improved understanding of bimolecular reactions in deceptively simple homogeneous media: From laboratory experiments to Lagrangian quantification

    NASA Astrophysics Data System (ADS)

    Zhang, Yong; Qian, Jiazhong; Papelis, Charalambos; Sun, Pengtao; Yu, Zhongbo

    2014-02-01

    Medium heterogeneity affects reaction kinetics by controlling the mixing of reactant particles, but the linkage between medium properties and reaction kinetics is difficult to build, even for simple, relatively homogeneous media. This study aims to explore the dynamics of bimolecular reactions, aniline + 1,2-naphthoquinone-4-sulfonic acid → 1,2-naphthoquinone-4-aminobenzene, in relatively homogeneous flow cells. Laboratory experiments were conducted to monitor the transport of both conservative and reactive tracers through columns packed with silica sand of specific diameters. The measured tracer breakthrough curves exhibit subdiffusive behavior with a late-time tail becoming more pronounced with decreasing sand size, probably due to the segregated flow regions formed more easily in columns packed with smaller size sand. Numerical analysis using a novel Lagrangian model shows that subdiffusion has a twofold effect on bimolecular reactions. While subdiffusion enhances the power-law growth rate of product mass by prolonging the exposure of reactant particles in the depletion zone, the global reaction rate is constrained because subdiffusion constrains the mobility of reactant particles. Reactive kinetics in deceptively simple homogeneous media is therefore controlled by subdiffusion, which is sensitive to the dimensions of packed sand.

  6. Is experience on a farm an effective approach to understanding animal products and the management of dairy farming?

    PubMed

    Mochizuki, Mariko; Osada, Masahiro; Ishioka, Katsumi; Matsubara, Takako; Momota, Yutaka; Yumoto, Norio; Sako, Toshinori; Kamiya, Shinji; Yoshimura, Itaru

    2014-03-01

    The understanding of animal products and dairy farming is important for the promotion of dairy farming. Thus, to examine the effects of farm experience on the understanding of animal products and the management of dairy farming, the interaction between students and dairy cows was investigated in groups of first-year veterinary nursing students in 2011 and 2012 (n = 201). These students included 181 women and 20 men. Nine items about dairy cows were presented in a questionnaire. The survey was performed before and after praxis on the educational farm attached to the authors' university. After praxis on the farm, increases occurred in the number of positive responses to the items involving the price of milk, dairy farming and the taste of milk. For these items, a significant difference (P < 0.05) was found between the scores obtained before and after training. The results of the study suggested that farm experience is useful for improving the understanding of animal products and dairy farming.

  7. Retention in orthodontics.

    PubMed

    Johnston, C D; Littlewood, S J

    2015-02-16

    Retention is necessary following orthodontic treatment to prevent relapse of the final occlusal outcome. Relapse can occur as a result of forces from the periodontal fibres around the teeth which tend to pull the teeth back towards their pre-treatment positions, and also from deflecting occlusal contacts if the final occlusion is less than ideal. Age changes, in the form of ongoing dentofacial growth, as well as changes in the surrounding soft tissues, can also affect the stability of the orthodontic outcome. It is therefore essential that orthodontists, patients and their general dental practitioners understand the importance of wearing retainers after orthodontic treatment. This article will update the reader on the different types of removable and fixed retainers, including their indications, duration of wear, and how they should be managed in order to minimise any unwanted effects on oral health and orthodontic outcomes. The key roles that the general dental practitioner can play in supporting their patients wearing orthodontic retainers are also emphasised.

  8. The existential dimension in general practice: identifying understandings and experiences of general practitioners in Denmark

    PubMed Central

    Assing Hvidt, Elisabeth; Søndergaard, Jens; Ammentorp, Jette; Bjerrum, Lars; Gilså Hansen, Dorte; Olesen, Frede; Pedersen, Susanne S.; Timm, Helle; Timmermann, Connie; Hvidt, Niels Christian

    2016-01-01

    Objective The objective of this study is to identify points of agreement and disagreements among general practitioners (GPs) in Denmark concerning how the existential dimension is understood, and when and how it is integrated in the GP–patient encounter. Design A qualitative methodology with semi-structured focus group interviews was employed. Setting General practice setting in Denmark. Subjects Thirty-one GPs from two Danish regions between 38 and 68 years of age participated in seven focus group interviews. Results Although understood to involve broad life conditions such as present and future being and identity, connectedness to a society and to other people, the existential dimension was primarily reported integrated in connection with life-threatening diseases and death. Furthermore, integration of the existential dimension was characterized as unsystematic and intuitive. Communication about religious or spiritual questions was mostly avoided by GPs due to shyness and perceived lack of expertise. GPs also reported infrequent referrals of patients to chaplains. Conclusion GPs integrate issues related to the existential dimension in implicit and non-standardized ways and are hindered by cultural barriers. As a way to enhance a practice culture in which GPs pay more explicit attention to the patients’ multidimensional concerns, opportunities for professional development could be offered (courses or seminars) that focus on mutual sharing of existential reflections, ideas and communication competencies. Key pointsAlthough integration of the existential dimension is recommended for patient care in general practice, little is known about GPs’ understanding and integration of this dimension in the GP–patient encounter.The existential dimension is understood to involve broad and universal life conditions having no explicit reference to spiritual or religious aspects.The integration of the existential dimension is delimited to patient cases where life

  9. Understanding students visions about environmental global problems. Experience and lessons learned of teaching in Lithuania.

    NASA Astrophysics Data System (ADS)

    Pereira, Paulo; Siarova, Hanna; Misiūnė, Ieva; Cerda, Artemi; Úbeda, Xavier

    2015-04-01

    Nowadays, environment is accepted to be an important element of our welfare. Our activities and societal status are strongly related with the quality of the environment where we live. On the other hand historical and cultural backgrounds shape importantly our views about the environment and how we act towards it in our daily life. In a context of globalization and increase of competition at international level, knowledge appears to be one of the key components for the advance of the word. Most of the knowledge produced comes from high level education institutions and research centres, which have responsibility to create and encourage critical thinking. Individuals aware of the problems can be more active and can push things forward. We think that environmental knowledge and awareness are fundamental for the future of the society. In order to develop better methodologies are developed if we have a better perception of students understanding of environmental problems. The objective of this work is to study the Lithuanian university level student's perception about some environmental challenges of our society. We selected several questions for the students rate according the relevance of the question, as "Air Pollution", "Waste Management", "Resources overexplotation", "Biodiversity reduction", "Human Overpopulation" "Poverty", "Global Warming/Climate change", Natural disasters", "Terrorism", "Economical crisis", "War and armed conflicts" and the "Spread of infectious diseases". We ask to the respondents to rate the importance using a likert scale (1=Not Important, 2= not so important, 3=important, 4=very important, 5=the most important). Among all the questions, the most rated where the Water pollution, the Spread of infectious diseases and Air Pollution and the less important where Biodiversity Reduction, Human overpopulation and climate change. These results helped us to identify where some efforts should be taken to raise student's awareness about global

  10. Iranian senior nursing managers’ experiences and understanding of social capital in the nursing profession

    PubMed Central

    Manoochehri, Houman; Lolaty, Hamideh Azimi; Hassani, Parkhideh; Arbon, Paul; Shorofi, Seyed Afshin

    2014-01-01

    Background: This study aimed to explore the role of social capital within the context of the nursing profession in Iran, based on the experience and perspectives of senior nursing managers. Materials and Methods: The study was conducted using the Graneheim and Lundman content analysis method. Using purposive sampling, 26 senior nursing managers from the Ministry of Health and Medical Education, the College of Nursing and Midwifery, the Iranian Nursing Organization, nursing associations and hospitals were selected, who participated in semi-structured in-depth interviews. Results: Content analysis revealed three main themes (social capital deficit, applying multiple strategies, and cultivating social capital) as well as eight categories which included professional remoteness, deficiency in professional potency, deficiency in professional exchanges, accumulation of personal social capital, accumulation of professional social capital, socio-political strategies, psychological–cognitive strategies, and ethical/spiritual strategies. The results show the perceived level of social capital in nursing in Iran, the application of some key strategies, and the principal rewards accrued from active participation in improving the social capital in nursing environment and profession. Conclusions: Efforts should be made to strengthen the social capital and apply key strategies with the aim of achieving personal and professional benefits for nurses, their patients, and co-workers, and for the delivery of healthcare in general. In this respect, the role of senior managers is vital in stimulating collective action within the profession, planning for the development of a culture of participation in healthcare services, helping to develop all fields of the profession, and developing and strengthening intra- and inter-professional exchanges and networking. PMID:25400673

  11. Using Space Weather Forecast Tools for Understanding Planetary Magnetospheres: MESSENGER Experience Applied to MAVEN Studies

    NASA Astrophysics Data System (ADS)

    Baker, Daniel N.; Dewey, R. M.; Brain, D. A.; Jakosky, Bruce; Halekas, Jasper; Connerney, Jack; Odstrcil, Dusan; Mays, M. Leila; Luhmann, Janet

    2015-04-01

    The Wang-Sheeley-Arge (WSA)-ENLIL solar wind modeling tool has been used to calculate the values of interplanetary magnetic field (IMF) strength (B), solar wind speed (V), density (n), ram pressure (~nV2), cross-magnetosphere electric field (VxB), Alfvén Mach number (MA), and other derived quantities of relevance for space weather purposes at Earth. Such parameters as solar wind dynamic pressure can be key for estimating the magnetopause standoff distance, as just one example. The interplanetary electric field drives many magnetospheric dynamical processes and can be compared with general magnetic activity indices and with the occurrence of energetic particle bursts within the Earth’s magnetosphere. Such parameters also serve as input to the global magnetohydrodynamic and kinetic magnetosphere models that are used to forecast magnetospheric and ionospheric processes. Such modeling done for Earth space weather forecasting has helped assess near-real-time magnetospheric behavior for MESSENGER at Mercury (as well as other mission analysis and Mercury ground-based observational campaigns). This solar-wind forcing knowledge has provided a crucial continuing step toward bringing heliospheric science expertise to bear on solar-planetary interaction studies. The experience gained from MESSENGER at Mercury is now being applied to the new observations from the MAVEN (Mars Atmosphere and Volatile Evolution) mission at Mars. We compare the continuous WSA-ENLIL results derived from modeling to the MAVEN SWIA and MAG data from mid-December 2014 to the present time. This provides a broader contextual view of solar wind forcing at Mars and also allows a broader validation of the ENLIL model results throughout the inner heliosphere.

  12. E. coli RS2GFP Retention Mechanisms in Laboratory-Scale Fractured Rocks: A Statistical Model

    NASA Astrophysics Data System (ADS)

    Rodrigues, S. N.; Qu, J.; Dickson, S. E.

    2011-12-01

    With billions of gallons of groundwater being withdrawn every day in the US and Canada, it is imperative to understand the mechanisms which jeopardize this resource and the health of those who rely on it. Porous media aquifers have typically been considered to provide significant filtration of particulate matter (e.g. microorganisms), while the fractures in fractured rock aquifers and aquitards are considered to act as contaminant highways allowing a large fraction of pathogens to travel deep into an aquifer relatively quickly. Recent research results indicate that fractured rocks filter out more particulates than typically believed. The goal of the research presented here is to quantify the number of E. coli RS2GFP retained in a single, saturated, laboratory-scale fracture, and to relate the retention of E. coli RS2GFP to the aperture field characteristics and groundwater flow rate. To achieve this goal, physical experiments were conducted at the laboratory-scale to quantify the retention of E. coli RS2GFP through several single, saturated, dolomitic limestone fractures under a range of flow rates. These fractures were also cast with a transparent epoxy in order to visualize the transport mechanisms in the various different aperture fields. The E. coli RS2GFP is tagged with a green-fluorescent protein (GFP) that is used to obtain visualization data when excited by ultraviolet light. A series of experiments was conducted, each of which involved the release of a known number of E. coli RS2GFP at the upstream end of the fracture and measuring the effluent concentration profile. These experiments were conducted using both the natural rock and transparent cast of several different aperture fields, under a range of flow rates. The effects of different aperture field characteristics and flow rates on the retention of E. coli RS2GFP will be determined by conducting a statistical analysis of the retention data under different experimental conditions. The images captured

  13. Waste Heat Approximation for Understanding Dynamic Compression in Nature and Experiments

    NASA Astrophysics Data System (ADS)

    Jeanloz, R.

    2015-12-01

    Energy dissipated during dynamic compression quantifies the residual heat left in a planet due to impact and accretion, as well as the deviation of a loading path from an ideal isentrope. Waste heat ignores the difference between the pressure-volume isentrope and Hugoniot in approximating the dissipated energy as the area between the Rayleigh line and Hugoniot (assumed given by a linear dependence of shock velocity on particle velocity). Strength and phase transformations are ignored: justifiably, when considering sufficiently high dynamic pressures and reversible transformations. Waste heat mis-estimates the dissipated energy by less than 10-20 percent for volume compressions under 30-60 percent. Specific waste heat (energy per mass) reaches 0.2-0.3 c02 at impact velocities 2-4 times the zero-pressure bulk sound velocity (c0), its maximum possible value being 0.5 c02. As larger impact velocities are implied for typical orbital velocities of Earth-like planets, and c02 ≈ 2-30 MJ/kg for rock, the specific waste heat due to accretion corresponds to temperature rises of about 3-15 x 103 K for rock: melting accompanies accretion even with only 20-30 percent waste heat retained. Impact sterilization is similarly quantified in terms of waste heat relative to the energy required to vaporize H2O (impact velocity of 7-8 km/s, or 4.5-5 c0, is sufficient). Waste heat also clarifies the relationship between shock, multi-shock and ramp loading experiments, as well as the effect of (static) pre-compression. Breaking a shock into 2 steps significantly reduces the dissipated energy, with minimum waste heat achieved for two equal volume compressions in succession. Breaking a shock into as few as 4 steps reduces the waste heat to within a few percent of zero, documenting how multi-shock loading approaches an isentrope. Pre-compression, being less dissipative than an initial shock to the same strain, further reduces waste heat. Multi-shock (i.e., high strain-rate) loading of pre

  14. Artificial size frequency distribution indices in laboratory experiments: Implications for understanding the evolution of Itokawa

    NASA Astrophysics Data System (ADS)

    Noviello, Jessica; Barnouin, Olivier S.; Ernst, Carolyn M.; Daly, Michael

    2014-11-01

    Asteroid 25143 Itokawa is a near-Earth irregular asteroid 535 by 294 by 209 meters in size [1]. The surface topography can be divided into the smooth lowlands and the rocky highlands. The origins of these regions could be due to the surface flow of fines from high to low points of gravitational potential [2]. Previous block studies conducted by Michikami et al. [3] and Mazrouei et al. [4] reported average size frequency distribution (SFD) indices on blocks larger than 6 m in diameter to be -3.1 ± 0.1 and -3.5 ± 0.1, respectively. Noviello et al. [5] reported preliminary results showing that blocks from 0.1 to 6 m in diameter had significantly lower SFD indices. They also reported that SFDs created from lowland image analyses consistently yield indices of around -2.71 ± 0.01, while the SFDs from highland images yield indices of roughly -2.00 ± 0.01 at the same scale. There are a number of geologic processes that could be responsible for the observed differences in SFD indices between different topographical regions. To quantify the effects of seismic shaking on SFD indices, we conducted simple laboratory experiments. Blocks were placed in a bin and slowly covered with sand and gravel, and then subjected to periods of moderate shaking in 10-second increments. The same methods used in the observational study were then applied to the experimental blocks to quantify the change in SFD index as the blocks were first covered and subsequently revealed. The initial results are: 1) As blocks are covered, in general the indices decrease; 2) Seismic shaking restores the indices; and 3) Larger blocks reappear faster than smaller rocks after shaking. This has implications for interpreting results of block count studies (the brazil nut effect [6]) and sample return missions, while also providing details about the physical expression of certain geologic processes on small bodies. [1] Fujiwara, A. et al., (2006) Science, 312, 1330-1334. [2] Miyamoto, H. et al., (2007) Science

  15. Laboratory experiments and continuous fluid monitoring at Campi Flegrei to understand pressure transients in hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Woith, Heiko; Mangiacapra, Annarita; Chiodini, Giovanni; Pilz, Marco; Walter, Thomas

    2015-04-01

    The hydrothermal system beneath Campi Flegrei is strongly affected by sub-surface processes as manifested by the existence of a geothermal "plume" below Solfatara (Bruno et al. 2007), associated with formation of new fumaroles and the spatial pattern of exhalation vents. Within the frame of MED-SUV (The MED-SUV project has received funding from the European Union Seventh Framework Programme (FP7) under Grant agreement no 308665), pressure tansients in the hydrothermal system of Campi Flegrei shall be studied using a combination of laboratory experiments and continuous pressure/temperature monitoring at fumaroles, mudpools, hot springs, and geothermal wells. Four groundwater monitoring sites were installed in September 2013: one in the Fangaia mud pool inside Solfatara and three within the geothermal area of Agnano, which is located roughly 3 km to the East of the Solfatara crater. In 2014 additional sensors were installed in Pisciarelli. Autonomous devices are being used to record the water level and water temperature at 10 minute intervals. Records reveal significant changes of the hydrothermal system in September 2013 at the Agnano main spring during the night from 23 to 24 September. Both, the water level and the water temperature dropped significantly, confirmed by visual inspection of the spa operators. The pool of the main spring almost emptied and the flow rate was significantly reduced, implying a profound change in the system. Similar water level drops occurred in the following months. Gas bubbles are likely to play a major role with respect to spatio-temporal variations in shallow fluid systems below Solfatara. Thus, additional to the field measurements we investigate potential bubble-related mechanisms capable to increase fluid pressure. The BubbleLab at GFZ has been setup. We are able to simulate earthquake ground motions with a shaking table, track the size and velocity of rising bubbles via a camera system, and quantify transients with a set of

  16. Challenges in understanding, modelling, and mitigating Lake Outburst Flood Hazard: experiences from Central Asia

    NASA Astrophysics Data System (ADS)

    Mergili, Martin; Schneider, Demian; Andres, Norina; Worni, Raphael; Gruber, Fabian; Schneider, Jean F.

    2010-05-01

    the outburst of landslide-dammed lakes) remains a challenge: • The knowledge about the onset of the process is often limited (bathymetry of the lakes, subsurface water, properties of dam (content of ice), type of dam breach, understanding of process chains and interactions). • The size of glacial lakes may change rapidly but continuously, and many lakes break out within a short time after their development. Continuous monitoring is therefore required to keep updated on the existing hazards. • Also the outburst of small glacial lakes may lead to significant debris floods or even debris flows if there is plenty of erodible material available. • The available modeling software packages are of limited suitability for lake outburst floods: e.g. software developed by the hydrological community is specialized to simulate (debris) floods with input hydrographs on moderately steep flow channels and with lower sediment loads. In contrast to this, programs for rapid mass movements are better suited on steeper slopes and sudden onset of the movement. The typical characteristics of GLOFs are in between and vary for different channel sections. In summary, the major bottlenecks remain in deriving realistic or worst case scenarios and predicting their magnitude and area of impact. This mainly concerns uncertainties in the dam break process, involved volumes, erosion rates, changing rheologies, and the limited capabilities of available software packages to simulate process interactions and transformations such as the development of a hyperconcentrated flow into a debris flow. In addition, many areas prone to lake outburst floods are located in developing countries with a limited scope of the threatened population for decision-making and limited resources for mitigation.

  17. The temperature and ion energy dependence of deuterium retention in lithium films

    NASA Astrophysics Data System (ADS)

    Buzi, Luxherta; Koel, Bruce E.; Skinner, Charles H.

    2016-10-01

    Lithium conditioning of plasma facing components in magnetic fusion devices has improved plasma performance and lowered hydrogen recycling. For applications of lithium in future high heat flux and long pulse duration machines it is important to understand and parameterize deuterium retention in lithium. This work presents surface science studies of deuterium retention in lithium films as a function of surface temperature, incident deuterium ion energy and flux. Initial experiments are performed on thin (3-30 ML) lithium films deposited on a single crystal molybdenum substrate to avoid effects due to grain boundaries, intrinsic defects and impurities. A monoenergetic and mass-filtered deuterium ion beam was generated in a differentially pumped Colutron ion gun. Auger electron spectroscopy and X-ray photoelectron spectroscopy were used to identify the elemental composition and temperature programmed desorption was used to measure the deuterium retention under the different conditions. Support was provided through DOE Contract Number DE-AC02-09CH11466.

  18. What's in a Domain: Understanding How Students Approach Questioning in History and Science

    ERIC Educational Resources Information Center

    Portnoy, Lindsay Blau; Rabinowitz, Mitchell

    2014-01-01

    How students ask questions as they learn has implications for understanding, retention, and problem solving. The current research investigates the influence of domain, age, and previous experience with content on the ways students approach questioning across history and science texts. In 3 experiments, 3rd-, 8th-, and 10th-grade students in large…

  19. Great apes' (Pan troglodytes, Pan paniscus, Gorilla gorilla, Pongo pygmaeus) understanding of tool functional properties after limited experience.

    PubMed

    Herrmann, Esther; Wobber, Victoria; Call, Josep

    2008-05-01

    Primates' understanding of tool functionality has been investigated extensively using a paradigm in which subjects are presented with a tool that they must use to obtain an out-of-reach reward. After being given experience on an initial problem, monkeys can transfer their skill to tools of different shapes while ignoring irrelevant tool changes (e.g., color). In contrast, monkeys without initial training perform poorly on the same tasks. Compared to most monkeys, great apes show a clear propensity for tool using and may not require as much experience to succeed on tool functionality tasks. We investigated this question by presenting 171 apes (Pan troglodytes, Pan paniscus, Gorilla gorilla, and Pongo pygmaeus) with several tool-use problems without giving them initial training or familiarizing them with the test materials. Apes succeeded without experience, but only on problems based on basic properties such as the reward being supported by an object. However, only minimal experience was sufficient to allow them to quickly improve their performance on more complex problems in which the reward was not in contact with the tool.

  20. When grief turns into love: understanding the experience of parents who have revived after losing a child due to cancer.

    PubMed

    Vega, Paula; Rivera, Maria Soledad; González, Rina

    2014-01-01

    A child's death caused by cancer generates a deep impact on his/her parents, who can be affected by serious health problems due to an impairment of their lifestyle. Notwithstanding their suffering, some parents manage to overcome it and discover a new meaning for their lives. The goal of this phenomenological study is to understand the lived experiences that help parents to revive after the death of their child due to cancer. The participants were fathers and mothers who believe that they have elaborated their mourning. Their lived experiences were collected in interviews they had previously agreed to give. The question that steered the interview was: "What is the experience you went through that helped you to revive after your child died due to cancer?" Data were analyzed using Streubert's method. Analyzing the interviews of the participants, 3 interweaved essences were detected: transition from surviving to reviving themselves; ascribing a sense and meaning to the life, agony, and death of a child; and helping other parents through one's own experience.

  1. Towards a richer understanding of school-age children's experiences of domestic violence: the voices of children and their mothers.

    PubMed

    Swanston, Jennifer; Bowyer, Laura; Vetere, Arlene

    2014-04-01

    Millions of children are exposed to domestic violence. How children negotiate and make sense of living with domestic violence is still under-researched. This study sought to capture the dual-perspectives of school-aged children and their mothers, to develop a richer understanding of children's experiences of domestic violence, using a community-based sample. A qualitative research design was employed, with interpretative phenomenological analysis used to interpret the data. Five school-aged children and three of their mothers participated in the study. Two master themes are discussed from the analysis of the children's perspective: domestic violence through the eyes of children; and learning from children's experiences. Two master themes are discussed from the analysis of the mothers' perspective: reflecting on the child in the context of domestic violence; and learning from mothers: insights, support and services. The crucial importance of the mother-child relationship in shaping children's experience of domestic violence was illustrated in both the perspectives; a finding which may have important implications for the development of interventions. It was also evident that children as young as eight were able to powerfully articulate their experiences of domestic violence.

  2. Causes and implications of colloid and microorganism retention hysteresis.

    PubMed

    Bradford, Scott A; Kim, Hyunjung

    2012-09-01

    Experiments were designed to better understand the causes and implications of colloid and microorganism retention hysteresis with transients in solution ionic strength (IS). Saturated packed column experiments were conducted using two sizes of carboxyl modified latex (CML) microspheres (0.1 and 1.1 μm) and microorganisms (coliphage φX174 and E. coli D21g) under various transient solution chemistry conditions, and 360 μm Ottawa sand that was subject to different levels of cleaning, namely, a salt cleaning procedure that removed clay particles, and a salt+acid cleaning procedure that removed clay and reduced microscopic heterogeneities due to metal oxides and surface roughness. Comparison of results from the salt and salt+acid treated sand indicated that microscopic heterogeneity was a major contributor to colloid retention hysteresis. The influence of this heterogeneity increased with IS and decreasing colloid/microbe size on salt treated sand. These trends were not consistent with calculated mean interaction energies (the secondary minima), but could be explained by the size of the electrostatic zone of influence (ZOI) near microscopic heterogeneities. In particular, the depth of local minima in the interaction energy has been predicted to increase with a decrease in the ZOI when the colloid size and/or the Debye length decreased (IS increased). The adhesive interaction was therefore largely irreversible for smaller sized 0.1 μm CML colloids, whereas it was reversible for larger 1.1 μm CML colloids. Similarly, the larger E. coli D21g exhibited greater reversibility in retention than φX174. However, direct comparison of CML colloids and microbes was not possible due to differences in size, shape, and surface properties. Retention and release behavior of CML colloids on salt+acid treated sand was much more consistent with mean interaction energies due to reduction in microscopic heterogeneities.

  3. Causes and implications of colloid and microorganism retention hysteresis

    NASA Astrophysics Data System (ADS)

    Bradford, Scott A.; Kim, Hyunjung

    2012-09-01

    Experiments were designed to better understand the causes and implications of colloid and microorganism retention hysteresis with transients in solution ionic strength (IS). Saturated packed column experiments were conducted using two sizes of carboxyl modified latex (CML) microspheres (0.1 and 1.1 μm) and microorganisms (coliphage φX174 and E. coli D21g) under various transient solution chemistry conditions, and 360 μm Ottawa sand that was subject to different levels of cleaning, namely, a salt cleaning procedure that removed clay particles, and a salt + acid cleaning procedure that removed clay and reduced microscopic heterogeneities due to metal oxides and surface roughness. Comparison of results from the salt and salt + acid treated sand indicated that microscopic heterogeneity was a major contributor to colloid retention hysteresis. The influence of this heterogeneity increased with IS and decreasing colloid/microbe size on salt treated sand. These trends were not consistent with calculated mean interaction energies (the secondary minima), but could be explained by the size of the electrostatic zone of influence (ZOI) near microscopic heterogeneities. In particular, the depth of local minima in the interaction energy has been predicted to increase with a decrease in the ZOI when the colloid size and/or the Debye length decreased (IS increased). The adhesive interaction was therefore largely irreversible for smaller sized 0.1 μm CML colloids, whereas it was reversible for larger 1.1 μm CML colloids. Similarly, the larger E. coli D21g exhibited greater reversibility in retention than φX174. However, direct comparison of CML colloids and microbes was not possible due to differences in size, shape, and surface properties. Retention and release behavior of CML colloids on salt + acid treated sand was much more consistent with mean interaction energies due to reduction in microscopic heterogeneities.

  4. Understanding Success of Historically Underrepresented Students at California State University, Monterey Bay through a Look at Their Institutional Experiences

    ERIC Educational Resources Information Center

    Boyce, Mary; Chukwuemeka, Veronica; Cruz-Uribe, Kathryn

    2013-01-01

    Unlike many universities, the historically under-represented (URM) students at California State University, Monterey Bay, typically graduate at a higher rate than non-URM students. Intense efforts have been made by staff and faculty to increase retention and graduation rates of all students. This paper examines the graduation rates in the context…

  5. Anaerobic treatment of a medium strength industrial wastewater at low-temperature and short hydraulic retention time: a pilot-scale experience.

    PubMed

    Esparza Soto, M; Solís Morelos, C; Hernández Torres, J J

    2011-01-01

    The aim of this work was to evaluate the performance of a pilot-scale upflow anaerobic sludge blanket (UASB) reactor during the treatment of cereal-processing industry wastewater under low-temperature conditions (17 degrees C) for more than 300 days. The applied organic loading rate (OLR(appl)) was gradually increased from 4 to 6 and 8 kg COD(sol)/m3d by increasing the influent soluble chemical oxygen demand (COD(sol)), while keeping the hydraulic retention time constant (5.2 h). The removal efficiency was high (82 to 92%) and slightly decreased after increasing the influent COD(sol) and the OLR(appl). The highest removed organic loading rate (OLR(rem)) was reached when the UASB reactor was operated at 8 kg COD(sol)/m3d and it was two times higher than that obtained for an OLR(appl) of 4 kg COD(sol)/m3d. Some disturbances were observed during the experimentation. The formation of biogas pockets in the sludge bed significantly complicated the biogas production quantification, but did not affect the reactor performance. The volatile fatty acids in the effluent were low, but increased as the OLR(appl) increased, which caused an increment of the effluent COD(sol). Anaerobic treatment at low temperature was a good option for the biological pre-treatment of cereal processing industry wastewater.

  6. Hands-On Particle Image Velocimetry Experience for Bioengineering Students Using the Interactive Flowcoach System to Understand Aneurysm Hemodynamics

    NASA Astrophysics Data System (ADS)

    Roszelle, Breigh N.; Okcay, Murat; Oztekin, B. Uygar; Frakes, David H.

    2012-11-01

    The Flowcoach system is a flow visualization and analysis platform from Interactive Flow Studies that uses particle image velocimetry (PIV) and computational fluid dynamics to provide interactive fluid dynamics education. In the spring of 2012, Flowcoach was used at Arizona State University to help teach bioengineering students about biofluid mechanics. A custom insert was made for Flowcoach to model an anatomical aneurysm that could be treated with a high-porosity flow diverting stent. Students performed PIV on the treated aneurysm model in small lab groups using Flowcoach and then wrote reports comparing their results to those from an untreated aneurysm model. The students were surveyed before and after the project and asked to rate their understanding of general biofluid mechanics, as well as experimental fluid mechanics and aneurysmal hemodynamics. Of the 76 students surveyed, 86% indicated an increase in their understanding of biofluid mechanics, and 90% indicated an increase in their understanding of both PIV and cerebral aneurysm hemodynamics. Students' written feedback showed that they felt Flowcoach and the interactive learning experience it provided were both interesting and beneficial to their future careers as engineers.

  7. Drug Retention Times

    SciTech Connect

    Center for Human Reliability Studies

    2007-05-01

    The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user.

  8. Strong-Sludge Gas Retention and Release Mechanisms in Clay Simulants

    SciTech Connect

    Gauglitz, Phillip A.; Buchmiller, William C.; Probert, Samuel G.; Owen, Antionette T.; Brockman, Fred J.

    2012-02-24

    The Hanford Site has 28 double-shell tanks (DSTs) and 149 single-shell tanks (SSTs) containing radioactive wastes that are complex mixes of radioactive and chemical products. The mission of the Department of Energy's River Protection Project is to retrieve and treat the Hanford tank waste for disposal and close the tank farms. A key aspect of the mission is to retrieve and transfer waste from the SSTs, which are at greater risk for leaking, into DSTs for interim storage until the waste is transferred to and treated in the Waste Treatment and Immobilization Plant. There is, however, limited space in the existing DSTs to accept waste transfers from the SSTs, and approaches to overcoming the limited DST space will benefit the overall mission. The purpose of this study is to summarize and analyze the key previous experiment that forms the basis for the relaxed controls and to summarize progress and results on new experiments focused on understanding the conditions that result in low gas retention. The previous large-scale test used about 50 m3 of sediment, which would be unwieldy for doing multiple parametric experiments. Accordingly, experiments began with smaller-scale tests to determine whether the desired mechanisms can be studied without the difficulty of conducting very large experiments. The most significant results from the current experiments are that progressively lower gas retention occurs in tests with progressively deeper sediment layers and that the method of gas generation also affects the maximum retention. Based on the results of this study, it is plausible that relatively low gas retention could occur in sufficiently deep tank waste in DSTs. The current studies and previous work, however, have not explored how gas retention and release will behave when two or more layers with different properties are present.

  9. Understanding the experiences and perceptions of African American female STEM majors at a single-sex HBCU

    NASA Astrophysics Data System (ADS)

    Wilson, Rahshida S.

    This study uses qualitative methods to explore and understand the experiences of African American female STEM majors at a single-sex historically Black university (HBCU). The study focuses on the perspectives of Black women and how they perceive the strategies and practices utilized at a single-sex HBCU that aid in fostering the successful development of Black women in STEM fields. Although limited to one institution, the findings shed light on the ways in which African American women experience the single-sex HBCU, and how the institution aids in their persistence in STEM majors. This study also discusses how such strategies and practices at a single-sex HBCU aid in mitigating the challenges and barriers that limit the attainment of African American women in STEM fields, and provides an opportunity for them to develop strong identities in STEM. Drawing on the findings, the paper concludes with recommendations for improving implementation of strategies revealed in historically Black colleges/universities and predominantly White colleges/ universities (PWIs). Recommendations for future research suggest that the experiences of African American women in single-sex and co-educational historically Black and predominantly White institutions could be further explored.

  10. Understanding how deployment experiences change over time: Comparison of female and male OEF/OIF and Gulf War veterans.

    PubMed

    Fox, Annie B; Walker, Brian E; Smith, Brian N; King, Daniel W; King, Lynda A; Vogt, Dawne

    2016-03-01

    Despite increased attention to the evolving nature of war, the unique challenges of contemporary deployment, and women's changing role in warfare, few studies have examined differences in deployment stressors across eras of service or evaluated how gender differences in deployment experiences have changed over time. Using data collected from two national survey studies, we examined war cohort and gender differences in veterans' reports of both mission-related and interpersonal stressors during deployment. Although Operation Enduring Freedom and Operation Iraqi Freedom veterans reported more combat experiences and greater preparedness for deployment compared to Gulf War veterans, Gulf War veterans reported higher levels of other mission-related stressors, including difficult living and working environment, perceived threat, and potential exposure to nuclear, biological, and chemical weapons. Gender differences also emerged, with men reporting greater exposure to mission-related stressors and women reporting higher levels of interpersonal stressors. However, the size and nature of gender differences did not differ significantly when comparing veterans of the two eras. By understanding how risk factors for PTSD differ based on war era and gender, veterans' experiences can be better contextualized.

  11. Physicochemical characterization of solute retention in solvent resistant nanofiltration: the effect of solute size, polarity, dipole moment, and solubility parameter.

    PubMed

    Darvishmanesh, Siavash; Vanneste, Johan; Tocci, Elena; Jansen, Johannes Carolus; Jansen, John; Tasselli, Franco; Tasseli, Franco; Degrève, Jan; Drioli, Enrico; Van der Bruggen, Bart

    2011-12-15

    Growing interest in nanofiltration for solvent purification requires a fundamental understanding of the physicochemical mechanisms of solute retention in organic solvent nanofiltration. In this study, the retention of a similar series of azo dyes with approximately similar molar mass (around 350 Da) by four nanofiltration membranes was studied. The membranes used are commercially available polymeric nanofiltration membranes with molecular weight cutoff between 150 and 300 Da (DuraMem150, StarMem122, NF270 and Desal-Dk). In order to correlate the retention with the size of the molecules, which is assumed to be one of the main factors that determines the retention, use was made of different parameters for the molecular size: molar mass, the Stokes diameter, the equivalent molar diameter, and the cavity surface in methanol and ethanol. All parameters were calculated by using molecular dynamics simulations. For each size parameter, the correlation with retention in nanofiltration experiments was calculated. For the StarMem122 membrane, zero retentions were observed due to the swelling of the membrane and pore size enlargement in methanol and ethanol. For the three other membranes, a fairly good correlation of the retention with the size could only be observed if the size difference between compounds is sufficiently large. Two other factors were studied by using molecular dynamics, i.e., the polarity of the molecule and the electron density of the molecule. The importance of these factors depends on the structure of the molecule as well as the functional groups of the polymer. A very good correlation has been observed for retention of dyes versus their dipole moment. Finally, the effect of solubility parameters of dyes on their retention did not show any significant effect.

  12. What Works in Student Retention? All Survey Colleges

    ERIC Educational Resources Information Center

    Habley, Wesley R.; McClanahan, Randy

    2004-01-01

    This report reflects ACT's commitment to assist colleges and universities to better understand the impact of campus practices on college student retention and degree completion. Survey findings indicate that: (1) Only 51.7% of campuses have identified an individual responsible for coordinating retention strategies; (2) Only 47.2% of campuses have…

  13. Incorporating carbon saturation concepts and nitrogen retention theory

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recent advances in soil C saturation concepts have increased our understanding of soil C storage and mineralization without explicit links to N retention and saturation theories. Here, we exploit a soil texture gradient to test hypotheses that link C saturation with soil 15N retention and nitrifica...

  14. IDENTIFYING RECRUITMENT AND RETENTION ISSUES FOR THE NATIONAL CHILDREN'S STUDY

    EPA Science Inventory

    Recruitment and Retention Issues for the National Children's Study
    Danelle T Lobdell1, Suzanne Gilboa2, Pauline Mendola1 (1US EPA, NHEERL; 2UNC Chapel Hill)

    A better understanding of the most effective recruitment techniques and retention strategies for longitudinal, co...

  15. The politics and anti-politics of the global fund experiment: understanding partnership and bureaucratic expansion in Uganda.

    PubMed

    Taylor, E Michelle; Harper, Ian

    2014-01-01

    After a decade of operations, the Global Fund is an institutional form in flux. Forced to cancel its eleventh round of funding due to a shortfall in donor pledges, the Fund is currently in firefighting mode, overhauling its leadership, governance structures, and operations. Drawing on a case study of Uganda, we look at how the original Global Fund vision to be a simple financial instrument has played out at the country level. Even prior to the cancellation of round 11, the proliferation of partners required to sustain the Global Fund to Fight AIDS, Tuberculosis and Malaria experiment led to increasing bureaucratization and an undermining of the Fund's own intentions to award life-saving grants according to need. Understanding these effects through the ethnographic material presented here may be one way of reflecting on the Fund's structure and practices as it struggles to reinvent itself in the face of criticism that it has impeded resource distribution.

  16. A relational understanding of sibling experiences of children with rare life-limiting conditions: findings from a qualitative study.

    PubMed

    Malcolm, Cari; Gibson, Faith; Adams, Sally; Anderson, Gillian; Forbat, Liz

    2014-09-01

    Mucopolysaccharidoses (MPS) and Batten disease are rare life-limiting conditions (LLCs) characterised by progressive and permanent physical and cognitive decline. The impact of such conditions on families, and notably on siblings, has not yet been described or documented. This paper presents data from a UK-wide study that sought to understand the family experience of supporting a child with the rare degenerative LLCs of MPS and Batten disease. The aim of this paper is to report sibling experiences related to these rare degenerative and progressive conditions, in order to inform the future development of supportive interventions. Eight siblings of children with MPS (n = 7) and Batten Disease (n = 1) participated in semi-structured qualitative interviews. A card sort technique was utilised to support and engage the children. Siblings are clearly impacted emotionally, pragmatically and relationally by the ill health of another child in the family. The data indicate four key themes which demonstrate impacts on siblings: perceptions of the condition and its symptoms, impact on daily life, emotional consequences and ways of coping. Siblings often had considerable knowledge of the condition and took on important roles in symptom management. However, these experiences were in the context of managing relationships within the family (often protecting parents from an awareness of how much they knew) and relationships at school (including distraction from learning and being bullied by peers). The data highlight how sibling experiences are generated through a combination of negative disability discourses and support through peers and family members. The data indicate how these features shift as a consequence of witnessing the advancement of their brother's or sister's condition and the emotional sequelae of disease progression. Exploration of siblings' experiences of living with such rare progressive and degenerative LLCs suggest the focus of interventions to support this

  17. Texas Teacher Recruitment and Retention Study.

    ERIC Educational Resources Information Center

    Texas Education Agency, Austin.

    This report on teacher recruitment and retention in Texas identifies and analyzes programs offered by higher education institutions, school districts, regional education service centers, and other organizations that address the teacher shortage in Texas. The study was undertaken with the understanding that teacher compensation issues are pervasive…

  18. How children with experiences of intimate partner violence towards the mother understand and relate to their father.

    PubMed

    Staf, Anna Georgsson; Almqvist, Kjerstin

    2015-01-01

    The aim of this study was to describe how, in the aftermath of intimate partner violence against the mother, children understand and relate to their father. Face-to-face interviews with four girls and four boys, aged between eight and twelve, were analysed using an interpretative phenomenological approach. All of the children had been exposed to the father's violence towards the mother. Two super ordinate themes were identified in the analysis: the disjunctive image of the father and being entangled in a conflict. The children's understanding of the father and their relationship with him was built on different versions of the father and his actions; those experienced by the child and those recounted to them. The situational context surrounding the described experience pervaded the image of the father. An ambiguity appeared to exist in the sense of different versions of the father and children described different emotions that could both hinder and elicit other feelings connected to the father. Children also conveyed the sense of being trapped or entangled in a conflict where their own needs and desires could be deemed as unsafe to express, and that they felt responsibility for dealing with the father's influence.

  19. The Effect of Testing on the Retention of Coherent and Incoherent Text Material

    ERIC Educational Resources Information Center

    de Jonge, Mario; Tabbers, Huib K.; Rikers, Remy M. J. P.

    2015-01-01

    Research has shown that testing during learning can enhance the long-term retention of text material. In two experiments, we investigated the testing effect with a fill-in-the-blank test on the retention of text material. In Experiment 1, using a coherent text, we found no retention benefit of testing compared to a restudy (control) condition. In…

  20. Average Soil Water Retention Curves Measured by Neutron Radiography

    SciTech Connect

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

    2011-01-01

    Water retention curves are essential for understanding the hydrologic behavior of partially-saturated porous media and modeling flow transport processes within the vadose zone. In this paper we report direct measurements of the main drying and wetting branches of the average water retention function obtained using 2-dimensional neutron radiography. Flint sand columns were saturated with water and then drained under quasi-equilibrium conditions using a hanging water column setup. Digital images (2048 x 2048 pixels) of the transmitted flux of neutrons were acquired at each imposed matric potential (~10-15 matric potential values per experiment) at the NCNR BT-2 neutron imaging beam line. Volumetric water contents were calculated on a pixel by pixel basis using Beer-Lambert s law after taking into account beam hardening and geometric corrections. To remove scattering effects at high water contents the volumetric water contents were normalized (to give relative saturations) by dividing the drying and wetting sequences of images by the images obtained at saturation and satiation, respectively. The resulting pixel values were then averaged and combined with information on the imposed basal matric potentials to give average water retention curves. The average relative saturations obtained by neutron radiography showed an approximate one-to-one relationship with the average values measured volumetrically using the hanging water column setup. There were no significant differences (at p < 0.05) between the parameters of the van Genuchten equation fitted to the average neutron radiography data and those estimated from replicated hanging water column data. Our results indicate that neutron imaging is a very effective tool for quantifying the average water retention curve.

  1. Understanding how drivers learn to anticipate risk on the road: A laboratory experiment of affective anticipation of road hazards.

    PubMed

    Kinnear, Neale; Kelly, Steve W; Stradling, Stephen; Thomson, James

    2013-01-01

    This study examines whether there is evidence that converging theories from the domains of risk and decision making, neuroscience, and psychology can improve our understanding of how drivers learn to appraise on-the-road hazards. Within the domain of decision making it is suggested that there are two distinct ways in which humans appraise risk: risk as feelings and risk as analysis. Meanwhile, current neurological theory, in the form of the Somatic Marker Hypothesis, supports the role of feelings and emotion as an evolved automated system of human risk appraisal that biases judgment and decision making. This study used skin conductance responses (SCRs) to measure learner, novice and experienced drivers' psycho-physiological responses to the development of driving hazards. Experienced drivers were twice as likely to produce an SCR to developing hazards as novice drivers and three times as likely when compared with learner drivers. These differences maintained significance when age, gender and exposure were controlled for. Further analysis revealed that novice drivers who had less than 1000 miles driving experience had anticipatory physiological responses similar to learner drivers, whereas novices who had driven more than 1000 miles had scores approaching those of experienced drivers. This demonstrated a learning curve mediated by driving experience supporting experiential learning as proposed within the Somatic Marker Hypothesis. A differentiation between cognitive and psycho-physiological responses was also found supporting theory that distinguishes between conscious and non-conscious risk appraisal.

  2. How do people of South Asian origin understand and experience depression? A protocol for a systematic review of qualitative literature

    PubMed Central

    Mooney, Roisin; Trivedi, Daksha; Sharma, Shivani

    2016-01-01

    Introduction Individuals from Black and Asian Minority Ethnic (BAME) groups are less likely to receive a diagnosis and to engage with treatment for depression. This review aims to draw on international literature to summarise what is known about how people specifically of South Asian origin, migrants and non-migrants, understand and experience depressive symptoms. The resulting evidence base will further inform practices aimed at encouraging help-seeking behaviour and treatment uptake. Methods and analysis A systematic review and thematic synthesis of qualitative literature conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Using predefined inclusion and exclusion criteria, electronic searches will be conducted across 16 databases. Study quality will be assessed using the Critical Appraisal Skills Programme (CASP). Data will be extracted independently by 2 reviewers. Ethics and dissemination Ethical approval is not required. A comprehensive evidence base of how people from South Asian backgrounds conceptualise and experience depression will better inform the design and delivery of mental health initiatives and advance directions for future research. Findings will be published in a peer-reviewed journal, and disseminated through existing networks for professionals, researchers, patients and the public. Trial registration number CRD42015026120. PMID:27577586

  3. Dynamic force microscopy simulator (dForce): A tool for planning and understanding tapping and bimodal AFM experiments

    PubMed Central

    Guzman, Horacio V; Garcia, Pablo D

    2015-01-01

    Summary We present a simulation environment, dForce, which can be used for a better understanding of dynamic force microscopy experiments. The simulator presents the cantilever–tip dynamics for two dynamic AFM methods, tapping mode AFM and bimodal AFM. It can be applied for a wide variety of experimental situations in air or liquid. The code provides all the variables and parameters relevant in those modes, for example, the instantaneous deflection and tip–surface force, velocity, virial, dissipated energy, sample deformation and peak force as a function of time or distance. The simulator includes a variety of interactions and contact mechanics models to describe AFM experiments including: van der Waals, Hertz, DMT, JKR, bottom effect cone correction, linear viscoelastic forces or the standard linear solid viscoelastic model. We have compared two numerical integration methods to select the one that offers optimal accuracy and speed. The graphical user interface has been designed to facilitate the navigation of non-experts in simulations. Finally, the accuracy of dForce has been tested against numerical simulations performed during the last 18 years. PMID:25821676

  4. A qualitative study to explore health professionals' experience of treating gout: understanding perceived barriers to effective gout management.

    PubMed

    Humphrey, Chloe; Hulme, Richard; Dalbeth, Nicola; Gow, Peter; Arroll, Bruce; Lindsay, Karen

    2016-06-01

    INTRODUCTION The management of gout is challenging and mainly occurs in primary care. This study aims to explore the experience of treating gout among primary care clinicians and understand the perceived barriers to effective therapy. METHODS Fourteen health professionals from primary care practices in South Auckland were recruited. Each participated in a semi-structured interview exploring their experience of treating and managing gout patients were analysed thematically. FINDINGS Participants described the large burden of gout in their communities and the importance of the clinician-patient relationship in gout management. Four themes summarise the perceived barriers to effective urate lowering therapy (ULT); unique gout factors, eg its intermittent nature and potential for stigmatisation; systemic barriers to optimal treatment, or barriers that emerge from working within a certain organisation; uncertainty about ownership, or who should carry responsibility for overcoming barriers to optimal treatment; and cultural barriers to optimal treatment. CONCLUSION Clinicians in primary practice perceive gout management to be mainly acute rather than preventive care. Patients may be stigmatised and management difficult particularly when diet is emphasised over ULT. Practice nurses are a group potentially available and willing to assist in educating patients. These findings may be helpful in planning for and improving healthcare in gout. KEYWORDS Gout; general practice; uric acid; primary health care; allopurinol; primary prevention.

  5. Understanding the impact of gendered roles on the experiences of infertility amongst men and women in Punjab

    PubMed Central

    2013-01-01

    women in Punjab, Pakistan. The insight obtained into the range of experiences can potentially contribute to deeper understanding of the social construction of infertility and childlessness in pronatalistic and patriarchal societies as well as the ways in which gender ideologies operationalise to marginalise women. PMID:23317173

  6. Understanding the impact of gendered roles on the experiences of infertility amongst men and women in Punjab.

    PubMed

    Mumtaz, Zubia; Shahid, Umber; Levay, Adrienne

    2013-01-15

    Punjab, Pakistan. The insight obtained into the range of experiences can potentially contribute to deeper understanding of the social construction of infertility and childlessness in pronatalistic and patriarchal societies as well as the ways in which gender ideologies operationalise to marginalise women.

  7. UNDERSTANDING METHANE EMISSIONS SOURCES AND VIABLE MITIGATION MEASURES IN THE NATURAL GAS TRANSMISSION SYSTEMS: RUSSIAN AND U.S. EXPERIENCE

    SciTech Connect

    Ishkov, A.; Akopova, Gretta; Evans, Meredydd; Yulkin, Grigory; Roshchanka, Volha; Waltzer, Suzie; Romanov, K.; Picard, David; Stepanenko, O.; Neretin, D.

    2011-10-01

    This article will compare the natural gas transmission systems in the U.S. and Russia and review experience with methane mitigation technologies in the two countries. Russia and the United States (U.S.) are the world's largest consumers and producers of natural gas, and consequently, have some of the largest natural gas infrastructure. This paper compares the natural gas transmission systems in Russia and the U.S., their methane emissions and experiences in implementing methane mitigation technologies. Given the scale of the two systems, many international oil and natural gas companies have expressed interest in better understanding the methane emission volumes and trends as well as the methane mitigation options. This paper compares the two transmission systems and documents experiences in Russia and the U.S. in implementing technologies and programs for methane mitigation. The systems are inherently different. For instance, while the U.S. natural gas transmission system is represented by many companies, which operate pipelines with various characteristics, in Russia predominately one company, Gazprom, operates the gas transmission system. However, companies in both countries found that reducing methane emissions can be feasible and profitable. Examples of technologies in use include replacing wet seals with dry seals, implementing Directed Inspection and Maintenance (DI&M) programs, performing pipeline pump-down, applying composite wrap for non-leaking pipeline defects and installing low-bleed pneumatics. The research methodology for this paper involved a review of information on methane emissions trends and mitigation measures, analytical and statistical data collection; accumulation and analysis of operational data on compressor seals and other emission sources; and analysis of technologies used in both countries to mitigate methane emissions in the transmission sector. Operators of natural gas transmission systems have many options to reduce natural gas losses

  8. Quinceaneras and Quadratics: Experiences of Latinas in State-Supported Residential Schools of Science and Math

    ERIC Educational Resources Information Center

    Sayman, Donna M.

    2013-01-01

    This qualitative study sought to understand the experiences of Latinas enrolled in residential state schools of science, technology, engineering, and math (STEM). Goals of the study focused on understanding experiences and identifying factors such as decisions to enroll, barriers and supports, and issues contributing to retention. These schools…

  9. Enhancing Vocabulary Retention by Embedding L2 Target Words in L1 Stories: An Experiment with Chinese Adult E-Learners

    ERIC Educational Resources Information Center

    Ge, Zi-Gang

    2015-01-01

    This study aims to investigate the effectiveness of a storytelling approach in Chinese adult e-learners' vocabulary learning. Two classes of 60 students participated in the experiment, with 30 in the experimental group and 30 in the control group. The storytelling approach and the rote memorization approach were employed by the two groups…

  10. An Appetitive Experience after Fear Memory Destabilization Attenuates Fear Retention: Involvement GluN2B-NMDA Receptors in the Basolateral Amygdala Complex

    ERIC Educational Resources Information Center

    Ferrer Monti, Roque I.; Giachero, Marcelo; Alfei, Joaquín M.; Bueno, Adrián M.; Cuadra, Gabriel; Molina, Victor A.

    2016-01-01

    It is known that a consolidated memory can return to a labile state and become transiently malleable following reactivation. This instability is followed by a restabilization phase termed reconsolidation. In this work, we explored whether an unrelated appetitive experience (voluntary consumption of diluted sucrose) can affect a contextual fear…

  11. Laboratory and Field Investigations of Dynamic Effects in Soil Water Retention Curve

    NASA Astrophysics Data System (ADS)

    Chiu, Yung-Chia; Tseng, Yen-Huiang; Ye, Jiun-Yan

    2015-04-01

    The unsaturated soil is a multi-phase system and the embedded physical mechanisms and chemical reactions are very complicated. The characteristics of groundwater flow and mechanisms of mass transport are still ambiguous so far. In order to fully understand the flow and transport in the unsaturated zone, the soil water retention curve plays an important role in description of water flow. However, the measurements and calculations of soil water retention curve are usually obtained under the static condition or steady state (equilibrium), in which the dynamic effects (non-equilibrium) are not considered, and the obtained relationship between capillary pressure and saturation is skeptical. Therefore, the sandbox experiments and field tests will be conducted to discuss the dynamic effects in the soil water retention curve and hysteresis effect in this study. In the laboratory, the relations between capillary pressure, saturation, the rate of change of water content, and dynamic constant are evaluated through different setting of boundary conditions and different sizes of particles. In the field, the tests are conducted to describe the soil water retention curve through the rain simulator and artificial evaporation. Besides, the dynamic dewpoint potentiameter is used to analyze the hysteresis effect of soil samples, and its results are compared with the results obtained from sandbox and field experiments. Finally, through a series of experiments, the relationship between capillary pressure and saturation under the dynamic effects is established, and the associated theories and mechanisms are discussed. The works developed in this study can provide as reference tools for the hydrogeological investigation and contaminated site remediation in the future. Keywords: capillary pressure, saturation, soil water retention curve, hysteresis, sandbox experiment, field test

  12. Recruitment and Retention of Black Students in Higher Education.

    ERIC Educational Resources Information Center

    Niba, Johnson N., Ed.; Norman, Regina, Ed.

    Six articles on recruitment and retention of black students are presented that cite dropping out as the factor most responsible for significantly impeding minority access to and successful progress in the collegiate experience. Increasingly, retention is becoming the ultimate yardstick for measuring institutional effectiveness, which translates…

  13. Using Maps to Retrieve Text: A Test of Conjoint Retention.

    ERIC Educational Resources Information Center

    Kulhavy, Raymond W.; And Others

    1992-01-01

    Two experiments with 129 college undergraduates tested the conjoint retention model by having subjects learn an intact map and text and then see the map as a retrieval cue in its original or reorganized form. Subjects remember more when cued by the original, supporting the conjoint retention theory. (SLD)

  14. The Effects of an Interactive Computer-Based Simulation Prior to Performing a Laboratory Inquiry-Based Experiment on Students' Conceptual Understanding of Physics.

    ERIC Educational Resources Information Center

    Zacharia, Zacharias; Anderson, O. Roger

    2003-01-01

    Investigates the effects of interactive computer-based simulations presented prior to inquiry-based laboratory experiments on students' conceptual understanding of mechanics, waves/optics, and thermal physics. Uses conceptual tests to assess conceptual understandings of each topic. Indicates that the use of the simulations improved students'…

  15. The Arctic Boreal Vulnerability Experiment: Observing, Understanding, and Predicting Social-Ecological Change in the Far North

    NASA Astrophysics Data System (ADS)

    Mack, M. C.; Goetz, S. J.; Kasischke, E. S.; Kimball, J. S.; Boelman, N.

    2015-12-01

    In the high northern latitudes, climate is warming more rapidly than anywhere else on Earth, transforming vulnerable arctic tundra and boreal forest landscapes. These changes are altering the structure and function of energy, water and carbon cycles, producing significant feedbacks to regional and global climate through changes in energy, water and carbon cycles. These changes are also challenging local and global society. At the local level, communities seek to adapt to new social-ecological regimes. At the global level, changing arctic and boreal systems are increasing becoming the focus of policy discussions at all levels of decision-making. National and international scientific efforts associated with a new NASA field campaign, the Arctic-Boreal Vulnerability Experiment (ABOVE) will advance our ability to observe, understand and predict the complex, multiscale and non-linear processes that are confronting the natural and social systems in this rapidly changing region. Over the next decade, the newly assembled ABOVE Science Team will pursue this overarching question: "How vulnerable or resilient are ecosystems and society to environmental change in the Arctic and boreal region of western North America?" Through integration of remote sensing and in situ observations with modeling of both ecological and social systems, the ABOVE Science Team will advance an interdisciplinary understanding of the Far North. In this presentation, we will discuss the conceptual basis for the ABOVE Field Campaign, describe Science Team composition and timeline, and update the community on activities. In addition, we will reflect on the visionary role of Dr. Diane Wickland, retired NASA Terrestrial Ecology Program Manager and lead of the Carbon Cycle & Ecosystems Focus Area, in the development and commencement of ABOVE.

  16. Conjoint Retention of Maps and Related Discourse.

    ERIC Educational Resources Information Center

    Kulhavy, Raymond, W.; And Others

    1985-01-01

    Two experiments used fifth grade students to test the hypothesis that conjointly presented verbal/spatial information facilitates retrieval from either stimulus format. Results support the notion of conjoint retention which assumes that related verbal/spatial arrays are stored in a fashion which allows separate use of both formats during…

  17. Rheometrical experiments with monitoring of resistivity: for a better understanding of the solid-fluid transition in clayey landslides

    NASA Astrophysics Data System (ADS)

    Carrière, Simon; Bièvre, Grégory; Chambon, Guillaume; Jongmans, Denis; Lebourg, Thomas; Larose, Eric

    2015-04-01

    Landslides are natural and complex phenomena which affect all types of geological formations and present a large variety of size, morphology and displacements rates. Among these phenomena, flow-like events in clay-rich formations are particularly complex due to the unpredictable acceleration and fluidization that characterize them. Because of their suddenness, such landslides constitute serious threat for population living in these areas. The forecast and the understanding of these events has then been an active topic of research in the scientific community during the past decades. In that respect, rheometrical experiments in the laboratory bring some insight into the processes occurring during the solid-fluid transition. In creep tests, the evolution of the shear strain rate is measured under constant levels of shear stress, allowing to follow changes in apparent viscosity with time and to observe fluidization. Rheometrical oscillatory tests have been designed to capture the evolution of the elastic shear modulus G (and hence the shear wave velocity Vs) during these creep phases. Previous results have shown that Vs exhibits a drop at the solid-fluid transition, with complex time-dependent effects which could lead, under transient loading, to the occurrence of Vs variations prior to the transition. A complementary way to understand the processes is to measure the electrical resistivity during these rheometrical tests. This parameter, which depends on the water content and salinity, as well as on the amount of clay particles, could also exhibit some changes before or during the solid-fluid transition. For that purpose, the metallic plates of the rotational rheometer have been replaced by new ones made in an electrically insulating material (PVC) with a configuration of four inserted circular electrodes. Rheometrical tests made with this new apparatus provide similar rheological results. For the electrical tests, the geometrical factor has been computed using Finite

  18. Qualitative research and its methods in epilepsy: Contributing to an understanding of patients' lived experiences of the disease.

    PubMed

    Rapport, Frances; Clement, Clare; Doel, Marcus A; Hutchings, Hayley A

    2015-04-01

    This review paper makes the case for the usefulness of qualitative research methods in the context of epilepsy research. It begins with an assessment of the current state of epilepsy literature and identifies gaps especially in the following: research in 'developing' countries and research around surgery for adults with epilepsy. It makes the case that disclosure of people's behaviors, actions, and reactions in different, often complex health-care situations can indicate how they bring meaning to their disease experiences and support needs. It shows the value of encouraging work that clarifies how patients manage their illness and how they understand changes in their health and well-being over the life course of their illness and how health-care professionals and other stakeholder groups care for those with epilepsy. The paper suggests a range of methods for addressing gaps in the literature and highlights a range of data collection, data analysis, and data interpretation and synthesis techniques that are appropriate in this context. It pays particular attention to the strengths of qualitative applications in mixed-methods research using an example from a recent ulcerative colitis drug trial that indicates how they can be integrated into study findings, add rich description, and enhance study outcomes. Ethnographic methodology is also presented, as a way of offering rare access to the 'lived experience' dimension, before the paper concludes with an assessment of the qualitative criteria of credibility, dependability, transferability, and confirmability for judging a study's 'trustworthiness'. The criteria evidence not only the trustworthiness of data and findings but also the ways in which a study has approached any challenges inherent in its research design.

  19. Tritium retention in TFTR

    SciTech Connect

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

    1988-04-01

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

  20. Secondary Retention Alternative.

    ERIC Educational Resources Information Center

    Baenen, Nancy R.; Hopkins, Patricia

    Two alternatives to retention in grade for secondary school students were evaluated in Austin (Texas). Both were designed to allow students who are potential retainees (PRs) to receive remediation in one semester. The Transitional Academic Program (TAP) allows PRs to enroll in ninth-grade courses while repeating eighth-grade courses they had…

  1. Principals Retention. Research Brief

    ERIC Educational Resources Information Center

    Muir, Mike

    2005-01-01

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

  2. Data Show Retention Disparities

    ERIC Educational Resources Information Center

    Adams, Caralee J.; Robelen, Erik W.; Shah, Nirvi

    2012-01-01

    New nationwide data collected by the U.S. Department of Education's civil rights office reveal stark racial and ethnic disparities in student retentions, with black and Hispanic students far more likely than white students to repeat a grade, especially in elementary and middle school. The contrast is especially strong for African-Americans. In the…

  3. Understanding the Use and Impact of Social Media Features on the Educational Experiences of Higher-Education Students in Blended and Distance-Learning Environments

    ERIC Educational Resources Information Center

    Scialdone, Michael John

    2014-01-01

    Students are increasingly expecting social media to be a component of their educational experiences both outside and inside of the classroom. The phenomenon of interest in this dissertation is understanding how the educational experiences of students are affected when social media are incorporated into online and blended course activities.…

  4. Grade 12 Students' Conceptual Understanding and Mental Models of Galvanic Cells before and after Learning by Using Small-Scale Experiments in Conjunction with a Model Kit

    ERIC Educational Resources Information Center

    Supasorn, Saksri

    2015-01-01

    This study aimed to develop the small-scale experiments involving electrochemistry and the galvanic cell model kit featuring the sub-microscopic level. The small-scale experiments in conjunction with the model kit were implemented based on the 5E inquiry learning approach to enhance students' conceptual understanding of electrochemistry. The…

  5. Genetics Home Reference: chylomicron retention disease

    MedlinePlus

    ... Retention Disease MalaCards: chylomicron retention disease Merck Manual Consumer Version: Hypolipidemia Merck Manual Consumer Version: Overview of Malabsorption Orphanet: Chylomicron retention disease ...

  6. Factor structure of the Benton Visual retention tests: dimensionalization of the Benton Visual retention test, Benton Visual retention test - multiple choice, and the Visual Form Discrimination Test.

    PubMed

    Lockwood, Courtney A; Mansoor, Yael; Homer-Smith, Elizabeth; Moses, James A

    2011-01-01

    Six sequential experiments were conducted on archival data of 610 U.S. Veterans seen at the Palo Alto Veteran's Affairs Hospital, to understand the dimensionalization of the Benton Visual retention test in both the recall (BVRT) and multiple-choice (BVRT-MC) format as well as the Visual Form Discrimination Test (VFDT). These tests were dimensionalized by the Wechsler Adult Intelligence Scale-Revised (WAIS-R) revealing a four-component model that explains 81.04% of the shared variance: the moderately difficult items (BVRT-MC and VFDT items 13-16) loaded with the WAIS-R Perceptual Organization, the easiest items (VFDT items 1-12, BVRT-MC items 1-12, and BVRT items 1-4) loaded separately with both WAIS-R Verbal Comprehension and Freedom from Distractibility, and the most difficult items (BVRT items 3-10) loaded weakly with WAIS-R Perceptual Organization.

  7. Mobile Learning and Student Retention

    ERIC Educational Resources Information Center

    Fozdar, Bharat Inder; Kumar, Lalita S.

    2007-01-01

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

  8. Improved understanding of the dynamic response in anisotropic directional composite materials through the combination of experiments and modeling

    NASA Astrophysics Data System (ADS)

    Alexander, C.

    2013-06-01

    Recently there has been renewed interest in the dynamic response of composite materials; specifically low density epoxy resin binders strengthened with continuous reinforcing fibers. This is in part due to the widespread use of carbon fiber composites in military, commercial, industrial, and aerospace applications. The design community requires better understanding of these materials in order to make full use of their unique properties. Experimental testing has been performed on a unidirectional carbon fiber - epoxy composite, engineered to have high uniformity and low porosity. Planar impact testing was performed at the Shock Thermodynamics Applied Research (STAR) facility at Sandia National Labs resulting in pressures up to 15 GPa in the composite material. Results illustrate the anisotropic nature of the response under shock loading. Along the fiber direction, a two-wave structure similar to typical elastic-plastic response is observed, however, when shocked transverse to the fibers, only a single bulk shock wave is detected. The two-wave structure persists when impact occurs at angles up to 45 degrees off the fiber direction. At higher pressures, the epoxy matrix dissociates resulting in a loss of anisotropy. Details of the experimental configurations and results will be presented and discussed. Greater understanding of the mechanisms responsible for the observed response has been achieved through the use of numerical modeling of the system at the micromechanical level using the CTH hydrocode. From the simulation results it is evident that the observed two-wave structure in the longitudinal fiber direction is the result of a fast moving elastic precursor wave traveling in the carbon fibers ahead of the bulk response in the epoxy resin. Similarly, in the transverse direction, results show a collapse of the resin component consistent with the experimental observation of a single shock wave traveling at speeds associated with bulk carbon. These results will be

  9. Early blood plutonium retention in nonhuman primates compared to the NCRP 156 wound biokinetic model.

    PubMed

    Konzen, Kevin; Brey, Richard; Guilmette, Raymond

    2015-03-01

    Data from animal experiments are relied upon for understanding the biokinetics of contaminant retention and excretion where insufficient human data exist. Records involving nonhuman primate experiments performed from 1973 to 1987 were collected and compiled by researchers at the Lawrence Berkeley Laboratory. These records included early blood samples that were taken after soluble plutonium was administered via intramuscular, subcutaneous, or intravenous injection. Samples were collected as early as 5 min post injection with several samples collected during the first few weeks. The NCRP 156 biokinetic model was developed primarily from animal experiments due to insufficient human data not influenced by chelation therapy. This work compared the NCRP 156 biokinetic model default transfer rate constants to the early blood excretion data from nonhuman primate experiments for 238Pu. These results indicated that the blood content of nonhuman primates exhibited "moderate" retention properties for simulated wound conditions. Additionally, there was no evidence of long-term retention of plutonium in the whole blood samples, confirming that plutonium was not incorporated within blood cells. Particle solubility characteristics should be considered for wounds when using the NCRP 156 wound biokinetic model.

  10. EFFECT OF ANAEROBIOSIS ON FILTER MEDIA POLLUTANT RETENTION

    EPA Science Inventory

    This paper presents the results of experiments conducted to determine if four potential filter media (sand, activated carbon, peat moss, and compost) could retain previously-trapped pollutants even under anaerobic conditions. The results indicated that permanent retention of heav...

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

    PubMed

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

    2012-06-01

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

  12. Psychogenic urinary retention.

    PubMed

    Bird, J R

    1980-01-01

    The literature on psychogenic urinary retention is reviewed. 2 cases treated by analytical psychotherapy are reported, in which significant demand for physical punishment was revealed and seen as linked to unacceptable, unconscious sadistic and aggressive feelings. Some psychodynamic aspects of what is considered to be "a disturbance of internal body space' are discussed. Psychogenic urinary retention has received little attention in the literature. It may represent the uneasy position this disorder of bodily function occupies in clinical practice, with clear physical symptoms and associated psychological factors. The condition is more frequent in females, usually young adults. Case histories regularly record the placid, passive presentation of these patients, childhood enuresis and disturbed backgrounds. The diagnosis, "hysteric', is frequent and most psychodynamic evaluations suggest the symptom represents a displacement of unacceptable sexual wishes and impulse. 2 patients treated by analytical psychotherapy are reported who, whilst fulfilling many of the criteria already noted, additionally revealed an intense desire for physical punishment. This punitive demand had less to do with unacceptable sexual wishes, than guilt at repressed aggressive drives of considerable magnitude. The role of aggression in the genesis of psychogenic urinary retention has so far been little studied.

  13. GABA[subscript A] Receptors Determine the Temporal Dynamics of Memory Retention

    ERIC Educational Resources Information Center

    McNally, Gavan P.; Augustyn, Katarzyna A.; Richardson, Rick

    2008-01-01

    Four experiments studied the role of GABA[subscript A] receptors in the temporal dynamics of memory retention. Memory for an active avoidance response was a nonmonotonic function of the retention interval. When rats were tested shortly (2 min) or some time (24 h) after training, retention was excellent, but when they were tested at intermediate…

  14. Making Decisions in the Dark: Disconnects between Retention Research and Middle-Level Practice

    ERIC Educational Resources Information Center

    Larsen, Donald E.; Akmal, Tariq T.

    2007-01-01

    This study of grade-level advancement/retention policies and procedures in 10 school districts shows how retention policy and procedure are disconnected from retention research. Administrators and teachers experience ethical dilemmas when district policy and prescribed practice collide with realities that underlie student failure. However, acts of…

  15. Previous Attempts to Debunk the Mythical Retention Chart and Corrupted Dale's Cone

    ERIC Educational Resources Information Center

    Subramony, Deepak Prem; Molenda, Michael; Betrus, Anthony K.; Thalheimer, Will

    2014-01-01

    Critics have been attempting to debunk the mythical retention chart at least since 1971. The earliest critics, David Curl and Frank Dwyer, were addressing just the retention data. Beginning around 2002, a new generation of critics has taken on the illegitimate combination of the retention chart and Edgar Dale's Cone of Experience--the corrupted…

  16. Learning and retention of quantum concepts with different teaching methods

    NASA Astrophysics Data System (ADS)

    Deslauriers, Louis; Wieman, Carl

    2011-06-01

    We measured mastery and retention of conceptual understanding of quantum mechanics in a modern physics course. This was studied for two equivalent cohorts of students taught with different pedagogical approaches using the Quantum Mechanics Conceptual Survey. We measured the impact of pedagogical approach both on the original conceptual learning and on long-term retention. The cohort of students who had a very highly rated traditional lecturer scored 19% lower than the equivalent cohort that was taught using interactive engagement methods. However, the amount of retention was very high for both cohorts, showing only a few percent decrease in scores when retested 6 and 18 months after completion of the course and with no exposure to the material in the interim period. This high level of retention is in striking contrast to the retention measured for more factual learning from university courses and argues for the value of emphasizing conceptual learning.

  17. A Cultural Approach to Understanding Professional Experiences of Foreign-Born Faculty in U.S. Educational Leadership Preparation Programs

    ERIC Educational Resources Information Center

    Khrabrova, Iryna M.

    2011-01-01

    The purpose of this study was to investigate professional experiences of foreign-born faculty members serving in U.S. educational leadership preparation programs utilizing a cultural approach to discern their lived experiences related to professional life. Cultural values reflected in professional life experiences were explored. The information…

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

    PubMed

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

    2015-04-01

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

  19. Increased local retention of reef coral larvae as a result of ocean warming

    NASA Astrophysics Data System (ADS)

    Figueiredo, Joana; Baird, Andrew H.; Harii, Saki; Connolly, Sean R.

    2014-06-01

    Climate change will alter many aspects of the ecology of organisms, including dispersal patterns and population connectivity. Understanding these changes is essential to predict future species distributions, estimate potential for adaptation, and design effective networks of protected areas. In marine environments, dispersal is often accomplished by larvae. At higher temperatures, larvae develop faster, but suffer higher mortality, making the effect of temperature on dispersal difficult to predict. Here, we experimentally calibrate the effect of temperature on larval survival and settlement in a dynamic model of coral dispersal. Our findings imply that most reefs globally will experience several-fold increases in local retention of larvae due to ocean warming. This increase will be particularly pronounced for reefs with mean water residence times comparable to the time required for species to become competent to settle. Higher local retention rates strengthen the link between abundance and recruitment at the reef scale, suggesting that populations will be more responsive to local conservation actions. Higher rates of local retention and mortality will weaken connectivity between populations, and thus potentially retard recovery following severe disturbances that substantially deplete local populations. Conversely, on isolated reefs that are dependent on replenishment from local broodstock, increases in local retention may hasten recovery.

  20. Understanding the Journey: A Phenomenological Study of College Students' Lived Experiences during the Weight-Loss Process

    ERIC Educational Resources Information Center

    Davis, Michael W.

    2013-01-01

    Although numerous studies have focused on understanding various aspects of the science of weight loss and weight gain in college students, understanding how the weight-loss process affects college students psychologically and behaviorally may help administrators and student affairs professionals to better work with students on their campuses. The…

  1. Leveraging Fourth and Sixth Graders' Experiences to Reveal Understanding of the Forms and Features of Distributed Causality

    ERIC Educational Resources Information Center

    Grotzer, Tina A.; Derbiszewska, Katarzyna; Solis, S. Lynneth

    2017-01-01

    Research has focused on students' difficulties understanding phenomena in which agency is distributed across actors whose individual-level behaviors converge to result in collective outcomes. Building on Levy and Wilensky (2008), this study identified features of distributed causality students understand and that may offer affordances for…

  2. Connecting Bourdieu, Winnicott, and Honneth: Understanding the Experiences of Non-Traditional Learners through an Interdisciplinary Lens

    ERIC Educational Resources Information Center

    West, Linden; Fleming, Ted; Finnegan, Fergal

    2013-01-01

    This paper connects Bourdieu's concepts of habitus, dispositions and capital with a psychosocial analysis of how Winnicott's psychoanalysis and Honneth's recognition theory can be of importance in understanding how and why non-traditional students remain in higher education. Understanding power relations in an interdisciplinary way makes…

  3. HPLC retention thermodynamics of grape and wine tannins.

    PubMed

    Barak, Jennifer A; Kennedy, James A

    2013-05-08

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

  4. Visual implant elastomer and anchor tag retention in largemouth bass

    USGS Publications Warehouse

    Hartman, K.J.; Janney, E.C.

    2006-01-01

    We double-marked largemouth bass Micropterus salmoides with Floy FD-68B anchor tags and visible implant elastomer (VIE) marks before stocking to compare retention of the two marks for age-0 (178 mm total length [TL]) and age-1 (273 mm TL) largemouth bass. In a short-term (31-d) evaluation, retention rate of anchor tags was over 94% for each age-class and retention of VIE marks was 98% in both age-classes. In a longer-term comparison of fish stocked into the Ohio River, retention was substantially higher for VIE marks (92.9%) than for anchor tags (42.9%) after 403 d (ages combined). Although anchor tags had high retention in two sizes of largemouth bass during the short-term experiment, they should not be used in situations where accurate identification of marked fish is required for periods longer than 123 d. ?? Copyright by the American Fisheries Society 2006.

  5. First University Experience and Student Retention Factors

    ERIC Educational Resources Information Center

    Madgett, Paul J.; Belanger, Charles H.

    2008-01-01

    The global marketplace has heightened the need for highly skilled personnel worldwide, underscoring the fact that a postsecondary education has almost become a necessary link to innovation and competitiveness. Canada, along with other industrialized nations, has an ageing population and is being challenged to alleviate specialized skill imbalances…

  6. Novel word retention in bilingual and monolingual speakers

    PubMed Central

    Kan, Pui Fong; Sadagopan, Neeraja

    2014-01-01

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

  7. Towards a Molecular Scale Understanding of Surface Chemistry and Photocatalysis on Metal Oxides: Surface Science Experiments and First Principles Theory

    SciTech Connect

    Diebold, Ulrike

    2015-01-29

    This project has provided an increased understanding of molecular processes and structure-activity relationships in photocatalytic systems. This could ultimately lead to guidelines on how to make TiO2-based photocatalytic systems more efficient. This directly relates to the Program’s mission to develop a mechanistic understanding of chemical reactions that pertain to environmental remediation and pollution control; energy production (photoelectrochemical and production of hydrogen); and novel materials synthesis.

  8. A Pedagogical Experience to Delve into Students' Sense of Cultural Belonging and Intercultural Understanding in a Rural School

    ERIC Educational Resources Information Center

    Ramos Holguín, Bertha; Aguirre Morales, Jahir; Matilde Hernández, Carmen

    2012-01-01

    Rural education has been the focus for several research studies which reveal a tendency to include students' home context in the curriculum. Considering the aforementioned statement, this article aims to share a pedagogical experience which was carried out in a rural school in Guavatá, Santander, Colombia. The main purpose of this experience was…

  9. A Search for Home: The Role of Art Therapy in Understanding the Experiences of Bosnian Refugees in Western Australia.

    ERIC Educational Resources Information Center

    Fitzpatrick, Fiona

    2002-01-01

    Studies the potential value of using art therapy as an intervention with refugees. The refugee experiences of two Bosnian women in Perth, Western Australia, were explored. Results of the study indicate that art therapy provides an effective tool for refugees to begin exploring some of the experiences associated with war, oppression, exile, and…

  10. Understanding the Lived Experiences of Novice Out-of-Field Teachers in Relation to School Leadership Practices

    ERIC Educational Resources Information Center

    Du Plessis, Anna; Carroll, Annemaree; Gillies, Robyn M.

    2015-01-01

    The lived experiences of novice teachers in out-of-field positions influence future career decisions and impact on their journey towards being competent and experienced practitioners, conversely their "life-world" is often misunderstood. The purpose of the study reported in this article is to investigate the lived experiences of these…

  11. Constructing a Theory of Individual Space: Understanding Transnational Migration through the Experience of Return Chinese Immigrants from Canada in Beijing

    ERIC Educational Resources Information Center

    Ding, Yueya

    2015-01-01

    Drawing on life history research, this study critically examines the transnational experiences of return Chinese immigrants from Canada in Beijing. Through the accounts of their experiences, it explores different integration and reintegration strategies, including self-adjustment, lifelong learning and flexible citizenship. A native concept of…

  12. The Everyday Mathematical Experiences and Understandings of Three, 4-Year-Old, African-American Children from Working-Class Backgrounds

    ERIC Educational Resources Information Center

    Benigno, Grace Marie R.

    2012-01-01

    This qualitative study examined the everyday mathematical experiences and understandings of three, 4-year-old, African-American children from working-class backgrounds. The study drew on Street, Baker, and Tomlin's (2005) broad, ideological model of mathematics as "social" and their analytic concepts of mathematical events (units of…

  13. The Effects of a Summer Science Camp Teaching Experience on Preservice Elementary Teachers' Science Teaching Efficacy, Science Content Knowledge, and Understanding of the Nature of Science

    ERIC Educational Resources Information Center

    Logerwell, Mollianne G.

    2009-01-01

    The purpose of this study was to investigate the impact of a summer science camp teaching experience on preservice elementary teachers' science teaching efficacy, science content knowledge, and understanding of the nature of science. Master's degree students enrolled in the elementary Fairfax Partnership Schools (FPS, n = 21) cohort served as the…

  14. Facilitating Conceptual Understanding of Gas-Liquid Mass Transfer Coefficient through a Simple Experiment Involving Dissolution of Carbon Dioxide in Water in a Surface Aeration Reactor

    ERIC Educational Resources Information Center

    Utgikar, Vivek P.; MacPherson, David

    2016-01-01

    Students in the undergraduate "transport phenomena" courses typically have a greater difficulty in understanding the theoretical concepts underlying the mass transport phenomena as compared to the concepts of momentum and energy transport. An experiment based on dissolution of carbon dioxide in water was added to the course syllabus to…

  15. Willing Retention of Misbelief

    NASA Astrophysics Data System (ADS)

    Moore, John W.

    2003-12-01

    Students also ought to get a better picture of how useful chemistry is and what insights it can provide regarding crucial problems that face society. A student who has completed a general chemistry course ought to have some understanding of how chemists are addressing major problems involving energy resources, adequate supplies of pure food and water, degradation of the environment, poverty, disease, and terrorism. Even better, the student should be aware that these problems are intertwined and solving one of them at the expense of any or all of the others is not a true solution. Better yet, the student should realize that with appropriate education and experience, the student could contribute significantly to society’s efforts to solve these problems. Former ACS President Ronald Breslow has suggested on numerous occasions that students are more likely to be attracted to a field in which the student can participate in solving important problems, but we persist in teaching chemistry as if it is a dead science, where everything is already known. Both learning and the unknown are powerful challenges that can motivate students to put forth their best efforts. We ought to make better use of them.

  16. Improved Climate Prediction through a System Level Understanding of Arctic Terrestrial Ecosystems: Next Generation Ecosystem Experiments (NGEE-Arctic)*

    NASA Astrophysics Data System (ADS)

    Hubbard, S. S.; Graham, D. E.; Hinzman, L. D.; Liang, L.; Liljedahl, A.; Norby, R. J.; Rogers, A.; Rowland, J. C.; Thornton, P. E.; Torn, M. S.; Riley, W. J.; Wilson, C. J.; Wullschleger, S. D.

    2013-12-01

    Characterized by vast amounts of carbon stored in permafrost and a rapidly evolving landscape, the Arctic has emerged as an important focal point for the study of climate change. Although recognized as an ecosystem highly vulnerable to climate change, mechanisms that govern feedbacks between the terrestrial and climate system are not well understood. Increasing our confidence in climate projections for high-latitude regions of the world requires coordinated investigations that target improved process understanding and model representation of important ecosystem-climate feedbacks. The Next-Generation Ecosystem Experiments (NGEE-Arctic) seeks to address this challenge by quantifying the physical, chemical, and biological behavior of terrestrial ecosystems in Alaska. The NGEE-Arctic project is a large, multi-disciplinary activity sponsored by the Department of Energy, Office of Science. Recent NGEE-Arctic research has focused on the highly dynamic landscapes of the North Slope Arctic tundra where thaw lakes, drained thaw lake basins, and ice-rich polygonal ground offer distinct land units for investigation and modeling. The project is working on the Barrow Environmental Observatory to study interactions that drive critical climate feedbacks within these environments through greenhouse gas fluxes and changes in surface energy balance associated with permafrost degradation and the many other processes that arise as a result of these landscape dynamics. Ongoing are mechanistic studies in the field and in the laboratory; modeling of critical and interrelated water, nitrogen, carbon, and energy dynamics; and characterization of important interactions from molecular to landscape scales that drive feedbacks to the climate system. A suite of climate-, intermediate- and fine-scale models are being used to guide observations and interpret data, while characterization information and process studies serve to initialize state variables in models, provide new algorithms and

  17. Twice in One Grade = A False Solution. A Review of the Pedagogical Practice of Grade Retention in Elementary Schools: What Do We Know? Should the Practice Continue?

    ERIC Educational Resources Information Center

    Ostrowski, Patricia Maslin

    This monograph reviews pertinent research and issues concerning grade retention in an effort to understand the implications for retention and promotion policies, especially in elementary schools. The monograph discusses 11 topics, including: (1) the historical context of retention and promotion; (2) the link between grade retention and dropouts;…

  18. The Effects of a Single Reminder Trial on Retention of a Motor Skill

    ERIC Educational Resources Information Center

    Fairbrother, Jeffrey T.; Shea, John B.

    2005-01-01

    Two experiments investigated the effects of a single reminder trial on immediate and delayed retention. Experiment 1 determined if beneficial effects of a reminder mat were a function of task order. Immediate retention performance benefited only when the reminder trial was practiced in the first block of trials. Experiment 2 added a 24-hr delayed…

  19. Repeated Retention Testing Effects Do Not Generalize to a Contextual Interference Protocol

    ERIC Educational Resources Information Center

    Fairbrother, Jeffrey T.; Shea, John B.; Marzilli, T. Scott

    2007-01-01

    Three experiments examined repeated retention testing effects in a contextual interference (CI) protocol. Retention was assessed at 10 min and 24 hr following acquisition or at just 24-hr for the one-test conditions. Experiments 1 and 2 used speeded-response key-pressing tasks. Dependent measures were total time and errors. Experiment 3 used…

  20. Retention and relapse in clinical practice.

    PubMed

    Littlewood, S J; Kandasamy, S; Huang, G

    2017-03-01

    Maintaining teeth in their corrected positions following orthodontic treatment can be extremely challenging. Teeth have a tendency to move back towards the original malocclusion as a result of periodontal, gingival, occlusal and growth related factors. However, tooth movement can also occur as a result of normal age changes. Because orthodontics is unable to predict which patients are at risk of relapse, those which will remain stable and the extent of relapse that will occur in the long-term, clinicians need to treat all patients as if they have a high potential to relapse. To reduce this risk, long term retention is advocated. This can be a significant commitment for patients, and so retention and the potential for relapse must form a key part of the informed consent process prior to orthodontic treatment. It is vital that patients are made fully aware of their responsibilities in committing to wear retainers as prescribed in order to reduce the chance of relapse. If patients are unable or unwilling to comply as prescribed, they must be prepared to accept that there will be tooth positional changes following treatment. There is currently insufficient high quality evidence regarding the best type of retention or retention regimen, and so each clinician's approach will be affected by their personal, clinical experience and expertise, and guided by their patients' expectations and circumstances.

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

    ERIC Educational Resources Information Center

    Shepard, Lorrie A.; Smith, Mary Lee

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

  2. The First Year University Experience: Using Personal Epistemology to Understand Effective Learning and Teaching in Higher Education

    ERIC Educational Resources Information Center

    Brownlee, Jo; Walker, Sue; Lennox, Sandra; Exley, Beryl; Pearce, Sharyn

    2009-01-01

    Personal epistemological beliefs, or beliefs about knowing, provide a way in which to understand learning in a range of educational contexts because they are considered to act as filters for all other knowledge and beliefs. In particular, they provide a useful framework for investigating learning and teaching for first year students in tertiary…

  3. Remembering Childhood: Do Our Memories and Experiences Influence Our Understanding of Early Childhood and Our Practice with Young Children?

    ERIC Educational Resources Information Center

    Horsley, Karen; Penn, Helen

    2014-01-01

    Students on the Early Childhood Studies degree programme at the University of East London were asked to reflect on their childhood memories and how these have shaped their understandings of early childhood and practices with young children. Students' rich and varied accounts reflect the diversity of largely non-traditional students from countries…

  4. Engineers and Their Role in Public Policy: An Active Learning Experience for Enhancing the Understanding of the State

    ERIC Educational Resources Information Center

    Acevedo, Jorge; Barros, Ricardo; Ramirez, Catalina; Realpe, Natalia

    2009-01-01

    To achieve effective intervention of engineers in the public sector, engineers should develop skills to comprehend their ethical and professional responsibility, and they should gain the necessary education to understand the possible impact of engineering solutions in a global and social context. An active learning process has been conceived,…

  5. Urban Secondary School Teachers' Understanding of Themselves as Adult Learners and Their Perceptions of Their Professional Development Experiences

    ERIC Educational Resources Information Center

    Fitzgerald, Jessica M.

    2014-01-01

    This action research study was designed to elicit urban, secondary school teachers' understandings of themselves as adult learners and their perceptions of job-embedded professional development in a single, urban school district in Connecticut. The conceptual framework that guided this study was derived from Knowles, Holton, and Swanson's (2011)…

  6. Park Visitors' Understandings, Values and Beliefs Related to Their Experience at Midway Geyser Basin, Yellowstone National Park, USA.

    ERIC Educational Resources Information Center

    Brody, Michael; Tomkiewicz, Warren

    2002-01-01

    Investigates the development of park visitors' knowledge, values, and beliefs during their visit to the Midway Geyser Basin. Draws on prior work in the areas of museum and informal education, and public understanding of science and cognitive psychology. Interprets the results in terms of park visitors' knowledge systems, how the experience…

  7. Understanding Stigma from a Sociocultural Context: Mothers' Experience of Stigma Directed towards Children with Special Educational Needs

    ERIC Educational Resources Information Center

    Uba, Chijioke Dike; Nwoga, Kechinyerem Amaka

    2016-01-01

    Although the need for a better understanding and deconstruction of the barriers that underpin and impede the realisation of inclusive education in many developing countries is acknowledged, few studies focus specifically on exploring how stigma affects the choices that parents in developing countries make on behalf of their children. This paper…

  8. Fluctuations of the experience of togetherness within the team over time: task-cohesion and shared understanding throughout a sporting regular season.

    PubMed

    Bourbousson, Jérôme; Fortes-Bourbousson, Marina

    2016-09-06

    Based on a diagnosis action research design, the present study assessed the fluctuations of the team experience of togetherness. Reported experiences of 12 basketball team members playing in the under-18 years old national championship were studied during a four-month training and competitive period. Time series analysis (Auto-Regressive Integrated Moving Average procedures) served to describe temporal properties of the way in which the fluctuations of task-cohesion and shared understanding were step-by-step experienced over time, respectively. Correlations, running-correlations and cross-lagged correlations were used to describe the temporal links that governed the relationships between both phenomena. The results indicated that the task-cohesion dimensions differed mainly for shared understanding dynamics in that their time fluctuations were not embedded in external events, and that the variations in shared understanding tend to precede 'individual attractions to the task' variations with seven team practical sessions. This study argues for further investigation of how 'togetherness' is experienced alternatively as a feeling of cohesion or shared understanding. Practitioner Summary: The present action research study investigated the experience that the team members have to share information during practice, and the subsequent benefices on team cohesion. Results call for specific interventions that make team members accept the fluctuating nature of team phenomena, to help them maintaining their daily efforts.

  9. First-hand sensory experience plays a limited role in children's early understanding of seeing and hearing as sources of knowledge: evidence from typically hearing and deaf children.

    PubMed

    Schmidt, Ellyn; Pyers, Jennie

    2014-11-01

    One early-developing component of theory of mind is an understanding of the link between sensory perception and knowledge formation. We know little about the extent to which children's first-hand sensory experiences drive the development of this understanding, as most tasks capturing this early understanding target vision, with less attention paid to the other senses. In this study, 64 typically hearing children (Mage  = 4.0 years) and 21 orally educated deaf children (Mage  = 5.44 years) were asked to identify which of two informants knew the identity of a toy animal when each had differing perceptual access to the animal. In the 'seeing' condition, one informant saw the animal and the other did not; in the 'hearing' condition, one informant heard the animal and the other did not. For both hearing and deaf children, there was no difference between performance on hearing and seeing trials, but deaf children were delayed in both conditions. Further, within both the hearing and deaf groups, older children outperformed younger children on these tasks, indicating that there is a developmental progression. Taken together, the pattern of results suggests that experiences other than first-hand sensory experiences drive children's developing understanding that sensory perception is associated with knowledge.

  10. Stability and Retention.

    PubMed

    Will, Leslie A

    2016-01-01

    Stability of tooth position in the broader sense considers all the forces that may act on the tooth. Reitan reported that significant forces remained in the periodontium after tooth movement, and he carried out research that demonstrated residual stretching of the crestal periodontal fibers more than 7 months after tooth movement. Brain demonstrated that severing the fibers reduced the relapse in tooth position in dogs. Edwards published a series of papers exploring the effects of surgical transection of the gingival fibers on tooth stability, recommending that circumferential fiberotomy be performed in order to increase posttreatment tooth stability. Other researchers have suggested ways to increase the stability of the incisors, which are typically most prone to relapse. Peck and Peck recommended that interproximal reduction be done to broaden the contact point. Boese also recommended interproximal reduction as part of a four-pronged approach to retention.

  11. Drug Retention Times

    SciTech Connect

    None, None

    2007-05-01

    The purpose of this monograph is to provide information on drug retention times in the human body. The information provided is based on plausible illegal drug use activities that might be engaged in by a recreational drug user. Based on anecdotal evidence, most people “party” during extended time away from the work environment. Therefore, the following scenarios were envisioned: (1) a person uses an illicit drug at a party on Saturday night (infrequent user); (2) a person uses a drug one time on Friday night and once again on Saturday night (infrequent user); and (3) a person uses a drug on Friday night, uses a drug twice on Saturday night, and once again on Sunday (frequent user).

  12. Molten core retention assembly

    DOEpatents

    Lampe, Robert F.

    1976-06-22

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

  13. Improving student retention in computer engineering technology

    NASA Astrophysics Data System (ADS)

    Pierozinski, Russell Ivan

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

  14. Understanding the Educational Experiences of Science Teachers in a Five-Year Teacher Education Program: A Phenomenological Study

    NASA Astrophysics Data System (ADS)

    Srivastava, Nitin

    This qualitative study provides an overview of educational experiences of six in-service and three pre-service secondary science teachers in the Benedum Collaborative Five-Year Teacher Education Program at a land-grant university. The researcher interviewed secondary science teachers on the experiences they found meaningful in various program components that influenced their teacher identity, beliefs about science pedagogy, and their sense of preparedness for teaching. Document analysis of teachers' journals and lesson plans supplemented the qualitative data in addition to the researcher's role and knowledge as an outsider (non-Benedum graduate) and insider (facilitator and instructor in the technology integration based classes for one year) of the Benedum Collaborative Five-Year Teacher Education Program. Findings also supported the Holmes (1986) and Goodlad (1990) views for extended field experiences and "collaborative culture" in teacher education for well-prepared teachers.

  15. Understanding Disabilities.

    ERIC Educational Resources Information Center

    Hartwell, Richard D.

    2001-01-01

    A language arts teacher at a California middle school describes an exercise he developed to help students understand disabilities through virtual, firsthand experience. As students simulate being blind, unable to walk, they learn how to adjust, innovate, compensate, cooperate, and empathize with one another. (MLH)

  16. Understanding Self.

    ERIC Educational Resources Information Center

    Ohio State Univ., Columbus. Center for Vocational and Technical Education.

    The learning experiences in the teacher's guide focus on helping students at the ninth grade level develop understanding of themselves as individuals and recognition that others may not perceive them as they see themselves. The materials are best utilized in a group guidance setting. Each student is encouraged to look at himself, to examine his…

  17. Multinational Experiment 7. Outcome 4: Understanding Inter-Domain Dependencies and Vulnerabilities. Conceptual and Pre-Doctrinal paper

    DTIC Science & Technology

    2013-01-31

    Focus on Space and Cyber 13 PART 2: BUILDING INTER-DOMAIN UNDERSTANDING 15 1- Inter-Domain Conceptual Framework 15 1.1 An Inter-Domain System 16...necessitate new solutions. These concerns pertain namely to trends such as the increase in cyber attacks or other technology-related trends, which, as...Security of the Members of the North Atlantic Treaty Organization, Active Engagement, Modern Defence, November 2010, pages 11-12: “ Cyber attacks are

  18. Toward a Record Retention Policy

    ERIC Educational Resources Information Center

    Vaughan, Jason

    2007-01-01

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

  19. For Worse, for Poorer and in Ill Health: How Women Experience, Understand and Respond to a Partner's Gambling Problems

    ERIC Educational Resources Information Center

    Patford, Janet

    2009-01-01

    Gambling is now big business in Australia and public expenditure on gambling is high. Some individuals gamble to excess with adverse consequences for themselves and their partner. The present study targeted women who had concerns about a current or previous partner's gambling and employed a qualitative methodology to explore their experiences,…

  20. Understanding the Lived Experience of a Sioux Indian Male Adolescent: Toward the Pedagogy of Hermeneutical Phenomenology in Education

    ERIC Educational Resources Information Center

    Kim, Jeong-Hee

    2012-01-01

    Currently, there is a resurgence of interests in phenomenology in education. This article sheds light on the importance of hermeneutical phenomenology in teaching and learning based on the lived experience of a Sioux Indian adolescent boy, elicited from an ethnographic case study conducted at an alternative high school in the US. Employing…

  1. Understanding Latino Students' Schooling Experiences: The Relevance of Skin Color among Mexican and Puerto Rican High School Students

    ERIC Educational Resources Information Center

    Fergus, Edward

    2009-01-01

    Background/Context: For the last 40 years, researchers have posited competing theories regarding the relative influence of social class background and racial-group membership on the school experiences, academic performance, behavior, and motivation of ethnic minority students. The general purpose of these competing theories has been to explain why…

  2. "A Girl Never Finishes Her Journey": Mixing Methods to Understand Female Experiences of Education in Contemporary Ethiopia

    ERIC Educational Resources Information Center

    Camfield, Laura

    2011-01-01

    Much research has suggested that focusing on the determinants of female enrolment and dropout tells us little about girls' experiences of schooling in developing countries and cannot explain variation in their educational trajectories. This paper draws on quantitative (n = 1177) and qualitative data (n = 15) collected by "Young Lives" in…

  3. Exploring How Research Experiences for Teachers Changes Their Understandings of the Nature of Science and Scientific Inquiry

    ERIC Educational Resources Information Center

    Buxner, Sanlyn R.

    2014-01-01

    The nature of science is a prevalent theme across United States national science education standards and frameworks as well as other documents that guide formal and informal science education reform. To support teachers in engaging their students in authentic scientific practices and reformed teaching strategies, research experiences for teachers…

  4. Research and Teaching: Understanding How Undergraduate Research Experiences Influence Student Aspirations for Research Careers and Graduate Education

    ERIC Educational Resources Information Center

    Adedokun, Omolola A.; Zhang, Dake; Parker, Loran Carleton; Bessenbacher, Ann; Childress, Amy; Burgess, Wilella Daniels

    2012-01-01

    Extant and emerging literature on undergraduate research experiences (UREs) focuses on the identification of their benefits to student participants. However, a notable limitation in these studies results from little or no examination of the processes through which UREs influence student career decisions and education aspirations. This study offers…

  5. Gudaga Goes to School Study: Methods Used in Understanding School Transitions and Early Education Experiences of an Urban Aboriginal Cohort

    ERIC Educational Resources Information Center

    Kaplun, Cathy; Knight, Jennifer; Grace, Rebekah; Dockett, Sue; Perry, Bob; Comino, Elizabeth; Jackson-Pulver, Lisa; Kemp, Lynn

    2016-01-01

    The Gudaga Goes to School Study described the transition to school and early education experiences of 117 urban Aboriginal children and their families. This paper outlines the methods and design of the study. A life course approach, employing multidimensional and multi-theoretical frameworks was used to capture the complexity of issues surrounding…

  6. Moving from Ethical Awareness to Deeper Understanding and Practice: Kindergarten Teachers' Experience with Developing Caring Dispositions in Children

    ERIC Educational Resources Information Center

    Nowak-Fabrykowski, Krystyna

    2010-01-01

    The goal of this research is to seek information from the Cleveland (Ohio) and Buffalo (New York) area kindergarten teachers about their experience in development of caring dispositions in children. Two hundred questionnaires were sent, one hundred to each city. There was a low response rate of less than 10% from both cities. A qualitative method…

  7. The researcher as experimental subject: using self-experimentation to access experiences, understand social phenomena, and stimulate reflexivity.

    PubMed

    Corti, Kevin; Reddy, Geetha; Choi, Ellen; Gillespie, Alex

    2015-06-01

    The current article argues that researcher-as-subject self-experimentation can provide valuable insight and systematic knowledge to social psychologists. This approach, the modus operandi of experimental psychology when the field was in its infancy, has been largely eclipsed by an almost exclusive focus on participant-as-subject other-experimentation. Drawing from the non-experimental first-person traditions of autoethnography, participant observation, and phenomenology, we argue that participating as both observer and subject within one's own social psychological experiment affords researchers at least three potential benefits: (1) access to "social qualia," that is, the subjective experience of social phenomena; (2) improved mental models of social phenomena, potentially stimulating new research questions; and (3) an enhanced ability to be reflexive about the given experiment. To support our position, we provide first-person self-reflections from researchers who have self-experimented with transformed social interactions involving Milgram's cyranoid method. We close by offering guidelines on how one might approach self-experimentation, and discuss a variety of first-person perspective ethnographic technologies that can be incorporated into the practice.

  8. Washington Center's Online Student Survey Validation Study: Surfacing Students' Individual and Collective Understanding of Their Learning Community Experiences

    ERIC Educational Resources Information Center

    Malnarich, Gillies; Pettitt, Maureen A.; Mino, Jack J.

    2014-01-01

    This article reports on findings from a mixed-methods validation study of the "Online Survey of Students' Experiences of Learning in Learning Communities". In the quantitative part of the study, we found strong correlations among survey items related to faculty behaviors, student behaviors, and critical thinking. Factor analysis yielded…

  9. Noncovalent Derivatization: A Laboratory Experiment for Understanding the Principles of Molecular Recognition and Self-Assembly through Phase Behavior

    ERIC Educational Resources Information Center

    Cannon, Amy S.; Warner, John C.; Koraym, Smaa A.; Marteel-Parrish, Anne E.

    2014-01-01

    An experiment focusing on the creation of phase diagrams involving nonconvalent derivatives of hydroquinone and bis[N,N-diethyl]terephthalamide (HQ-DETPA) is presented. A phase diagram was assembled by taking samples of different compositions (i.e., 40% hydroquinone and 60% bis[N,N-diethyl]terephthalamide, 70%/30%, etc.) and determining the…

  10. Understanding the Relationship between Singapore Preservice Teachers' ICT Course Experiences and Technological Pedagogical Content Knowledge (TPACK) through ICT Course Evaluation

    ERIC Educational Resources Information Center

    Koh, Joyce Hwee Ling; Woo, Huay-Lit; Lim, Wei-Ying

    2013-01-01

    Teacher education institutions conduct information and communications technology (ICT) courses to prepare preservice teachers (or initial teacher education candidates) to support their teaching practice with appropriate ICT tools. ICT course evaluations based on preservice teachers' perception of course experiences are limited in indicating the…

  11. Using an Advanced Computational Laboratory Experiment to Extend and Deepen Physical Chemistry Students' Understanding of Atomic Structure

    ERIC Educational Resources Information Center

    Hoffman, Gary G.

    2015-01-01

    A computational laboratory experiment is described, which involves the advanced study of an atomic system. The students use concepts and techniques typically covered in a physical chemistry course but extend those concepts and techniques to more complex situations. The students get a chance to explore the study of atomic states and perform…

  12. Understanding Mothers' Experiences of Infant Daycare: A New Approach Using Computer-Assisted Analysis of Qualitative Data.

    ERIC Educational Resources Information Center

    Rolfe, Sharne; And Others

    This paper reports on a small-scale introductory study of Australian mothers' experiences of infant day care. Ten employed, middle- and lower-socioeconomic status women with an infant in center-based day care were interviewed. Brief narrative examples from the mothers' accounts are presented. Discussion then concentrates on a new approach to…

  13. Understanding the Complexity of Becoming a Teacher Educator: Experience, Belonging, and Practice within a Professional Learning Community

    ERIC Educational Resources Information Center

    Williams, Judy; Ritter, Jason; Bullock, Shawn M.

    2012-01-01

    This article reports a literature review of self-studies by beginning teacher educators examining their experiences of the transition from classroom teaching to teacher educator. The authors conclude that becoming a teacher educator involves several complex and challenging tasks: examining beliefs and values grounded in personal biography,…

  14. Predictors of Participant Retention in Infertility Treatment Trials

    PubMed Central

    Kuang, Hongying; Jin, Susan; Thomas, Tracey; Engmann, Lawrence; Hansen, Karl R.; Coutifaris, Christos; Casson, Peter; Christman, Gregory; Alvero, Ruben; Santoro, Nanette; Eisenberg, Esther; Diamond, Michael P; Legro, Richard S.; Zhang, Heping

    2015-01-01

    Objective To identify variables associated with retention (or dropout) in infertility clinical trials. Retention of subjects in randomized controlled clinical trials (RCTs) has received considerable attention, but there have been few consistent findings. Design Secondary analysis of data from RCTs. Setting RCTs conducted by academic medical centers in the U.S. Patients Women with polycystic ovary syndrome or couples with unexplained infertility, 18–39 years of age. Interventions This study is not an intervention study, but the patients in the original RCTs were treated with any or combination of metformin, clomiphene citrate, letrozole, and gonadotropins. Main Outcome Measure Successful retention versus dropout during the RCTs. Results Race, ethnicity, BMI, insurance coverage, history of smoking, and history of alcohol use were significantly associated with retention whether they were considered in bivariate analyses or a multivariable logistic model. Specifically, white race, higher income, having graduate degrees, normal weight, better insurance coverage, non-smokers, and those who reported current use of alcohol at the start of the trial, had higher retention rates. Conclusion We identified several additive and persistent predictors of retention that can be used to guide the conduct of RCTs and improve the retention rate. Given the limitation of our association analysis, methodologically sound and theoretically grounded research are warranted so that high quality data can be collected to improve our understanding on the causes of dropout. PMID:26354094

  15. A design-of-experiments approach for the optimization and understanding of the cross-metathesis reaction of methyl ricinoleate with methyl acrylate.

    PubMed

    Ho, Thao T T; Jacobs, Tina; Meier, Michael A R

    2009-01-01

    A design-of-experiments approach for the investigation of the cross-metathesis of methyl ricinoleate with methyl acrylate is described. Two second-generation metathesis initiators were studied using different reaction conditions, revealing optimal reaction conditions for each catalyst. Interestingly, the two catalysts showed completely different temperature response profiles. As a result of these investigations, suitable reaction conditions for the sustainable production of two value-added chemical intermediates were derived. Moreover, the design-of-experiments approach provided valuable information for a thorough understanding of catalytic reactions that would be more difficult to obtain by classic approaches.

  16. Understanding the Use-wears on Non-retouched Shells Mytilus galloprovincialis. and Ruditapes decussatus by Performing Wood Working Experiment: An Experimental Approach

    NASA Astrophysics Data System (ADS)

    Tumung, Laxmi; Bazgir, Behrouz; Ahmadi, Kamran; Shadmehr, Abdolkarim

    2012-07-01

    This paper is an experimental attempt to understand the use-wear comes on non-retouched shells Ruditapes decussatus and Mytilus galloprovincialis. These species have been selected due to their variation in shape, size and edge type. In wood working experiment Celtus australis wood is used to perform the activities like scrapping and cutting wood. The ESEM results show the usewears in the form of linear marks, edge rounding, edge facture, polish and micro-pitting. Experiments also showed some macro-fractures.

  17. A Loss of Moral Experience: Understanding HIV-Related Stigma in the New York City House and Ball Community

    PubMed Central

    2013-01-01

    Objectives. I incorporated qualitative methods to explore how HIV-related stigma functions in New York City’s House and Ball Community (HBC). Methods. From January through March 2009, I conducted 20 in-depth 1-on-1 interviews with a diverse sample of New York City HBC members. Interviews addressed perceptions of HIV-related stigma, the treatment of HIV-positive members in the community, and the potential impact of HIV-related stigma on risk behaviors. Results. HIV-related stigma contributes to a loss of moral experience for HBC members. Moral experience (i.e., threats to what really matters in a community) disrupts established social connections and hinders the attainment of “ball status” (i.e., amassing social recognition) in the local world of these individuals. Conclusions. My recommendations address HIV-related stigma in the New York City HBC from the vantage of moral experience and highlight the need for longitudinal studies of individual house members and for the implementation of stigma-focused interventions in the community that utilize the unique ball status hierarchy and HBC network to influence social norms surrounding the treatment of HIV-positive community members. PMID:23237182

  18. Veterans’ Perspectives on Interventions to Improve Retention in HIV Care

    PubMed Central

    Kertz, Barbara L.; Cully, Jeffery A.; Stanley, Melinda A.; Davila, Jessica A.; Dang, Bich N.; Rodriguez-Barradas, Maria C.; Giordano, Thomas P.

    2016-01-01

    Poor retention in HIV medical care is associated with increased mortality among patients with HIV/AIDS. Developing new interventions to improve retention in HIV primary care is needed. The Department of Veteran Affairs (VA) is the largest single provider of HIV care in the US. We sought to understand what veterans would want in an intervention to improve retention in VA HIV care. We conducted 18 one-on-one interviews and 15 outpatient focus groups with 46 patients living with HIV infection from the Michael E. DeBakey VAMC (MEDVAMC). Analysis identified three focus areas for improving retention in care: developing an HIV friendly clinic environment, providing mental health and substance use treatment concurrent with HIV care and encouraging peer support from other Veterans with HIV. PMID:26829641

  19. Rethinking Student Retention in Community Colleges.

    ERIC Educational Resources Information Center

    Wild, Linda; Ebbers, Larry

    2002-01-01

    States that student retention is significant for measuring institutional effectiveness in the prevailing environment of accountability and budgetary constraints. Presents recommendations for increasing retention, including training staff on retention issues, reviewing admission and advising strategies affecting minority populations, and piloting…

  20. Orthodontic retention: why when and how?

    PubMed

    McNally, M; Mullin, M; Dhopatkar, A; Rock, W P

    2003-10-01

    Retention is normally required after active orthodontic tooth movement to hold the teeth in their new positions. This article reviews the principles of orthodontic retention and describes common retention regimes and appliances.

  1. Modeling Polymer Stabilized Nano-scale Zero Valent Iron Transport Experiments in Porous Media to Understand the Transport Behavior

    NASA Astrophysics Data System (ADS)

    Mondal, P.; Krol, M.; Sleep, B. E.

    2015-12-01

    A wide variety of groundwater contaminants can be treated with nano-scale zero valent iron (nZVI). However, delivery of nZVI in the subsurface to the treatment zones is challenging as the bare nZVI particles have a higher tendency to agglomerate. The subsurface mobility of nZVI can be enhanced by stabilizing nZVI with polymer, such as carboxymethyl cellulose (CMC). In this study, numerical simulations were conducted to evaluate CMC stabilized nZVI transport behavior in porous media. The numerical simulations were based on a set of laboratory-scale transport experiments that were conducted in a two-dimensional water-saturated glass-walled sandbox (length - 55 cm; height - 45 cm; width - 1.4 cm), uniformly packed with silica sand. In the transport experiments: CMC stabilized nZVI and a non-reactive dye tracer Lissamine Green B (LGB) were used; water specific discharge and CMC concentration were varied; movements of LGB, and CMC-nZVI in the sandbox were tracked using a camera, a light source and a dark box. The concentrations of LGB, CMC, and CMC-nZVI at the sandbox outlet were analyzed. A 2D multiphase flow and transport model was applied to simulate experimental results. The images from LGB dye transport experiments were used to determine the pore water velocities and media permeabilities in various layers in the sand box. These permeability values were used in the subsequent simulations of CMC-nZVI transport. The 2D compositional simulator, modified to include colloid filtration theory (CFT), treated CMC as a solute and nZVI as a colloid. The simulator included composition dependent viscosity to account for CMC injection and mixing, and attachment efficiency as a fitting parameter for nZVI transport modeling. In the experiments, LGB and CMC recoveries were greater than 95%; however, CMC residence time was significantly higher than the LGB residence time and the higher CMC concentration caused higher pressure drops in the sandbox. The nZVI recovery was lower than 40

  2. In-services and empty threats: The roles of organizational practices and workplace experiences in shaping U.S. educators' understandings of students' rights.

    PubMed

    Thompson, Jason; Arum, Richard; Edelman, Lauren B; Morrill, Calvin; Tyson, Karolyn

    2015-09-01

    This paper applies theoretical frameworks from organizational sociology and sociolegal studies to examine factors associated with educators' conceptions of students' rights to due process in disciplinary actions. We analyze a unique representative data set of 402 teachers and 200 administrators in U.S. high schools to investigate how educators understand the rights to due process articulated in the Supreme Court case of Goss v. Lopez (1975). We then examine whether individual characteristics and participation in organizational processes are associated with educators' understandings of students' due process rights. Findings suggest that educators' understandings of students' entitlements to due process vary with educators' level of education, experience of school-related legal threats, and participation in district or diocese in-service training programs on students' rights. Results point to organizational climate as a key factor in shaping educators' rights conceptions and the role of law in American schools.

  3. Gas chromatographic retention characteristics of phenols with Superox-20M

    SciTech Connect

    White, C.M.; Li, N.C.

    1982-08-01

    The gas chromatographic retention characteristics of a variety of underivatized phenols have been studied by using Superox-20M coated on fused silica. The relative retention times of thes compounds were measured at 160, 150, and 140/sup 0/C in order to determine the effect of operating temperature on relative retention. This information is used to predict relative retention times of phenols for which we had no standards. The linear temperature-programmed retention indexes of the solutes were measured. The retention of phenols on this phase is a function of the compounds vapor pressure, its ability to hydrogen bond with the stationary phase, and the strengths of those hydrogen bonds. These properties are in turn governed by steric, inductive, and resonance effects of the substituents. Linear free-energy relations between the logarithm of the ratio of the activity coefficients of phenol to substituted phenol (calculated from relative retention data) and the chromatographic substituent constant, sigma/sub c/, have been determined for some phenols on Superox-20M. Lastly, it was shown by nuclear magnetic resonance experiments that Superox-20M is apparently a poly(ethylene glycol) (also called a polyoxiran or poly(ethylene oxide)). 5 figures, 3 tables.

  4. Gain in student understanding of the role of random variation in evolution following teaching intervention based on luria-delbruck experiment.

    PubMed

    Robson, Rachel L; Burns, Susan

    2011-01-01

    Undergraduate students in introductory biology classes are typically saddled with pre-existing popular beliefs that impede their ability to learn about biological evolution. One of the most common misconceptions about evolution is that the environment causes advantageous mutations, rather than the correct view that mutations occur randomly and the environment only selects for mutants with advantageous traits. In this study, a significant gain in student understanding of the role of randomness in evolution was observed after students participated in an inquiry-based pedagogical intervention based on the Luria-Delbruck experiment. Questionnaires with isomorphic questions regarding environmental selection among random mutants were administered to study participants (N = 82) in five separate sections of a sophomore-level microbiology class before and after the teaching intervention. Demographic data on each participant was also collected, in a way that preserved anonymity. Repeated measures analysis showed that post-test scores were significantly higher than pre-test scores with regard to the questions about evolution (F(1, 77) = 25.913, p < 0.001). Participants' pre-existing beliefs about evolution had no significant effect on gain in understanding of this concept. This study indicates that conducting and discussing an experiment about phage resistance in E. coli may improve student understanding of the role of stochastic events in evolution more broadly, as post-test answers showed that students were able to apply the lesson of the Luria-Delbruck experiment to other organisms subjected to other kinds of selection.

  5. Parental understanding and self-blame following sudden infant death: a mixed-methods study of bereaved parents' and professionals' experiences

    PubMed Central

    Griffiths, Frances; Sidebotham, Peter

    2016-01-01

    Objectives Improvements in our understanding of the role of modifiable risk factors for sudden infant death syndrome (SIDS) mean that previous reassurance to parents that these deaths were unpreventable may no longer be appropriate. This study aimed to learn of bereaved parents' and healthcare professionals' experiences of understanding causes of death following detailed sudden unexpected death in infancy (SUDI) investigations. The research questions were: How do bereaved parents understand the cause of death and risk factors identified during detailed investigation following a sudden unexpected infant death? What is the association between bereaved parents' mental health and this understanding? What are healthcare professionals' experiences of sharing such information with families? Design This was a mixed-methods study using a Framework Approach. Setting Specialist paediatric services. Participants Bereaved parents were recruited following detailed multiagency SUDI investigations; 21/113 eligible families and 27 professionals participated giving theoretical saturation of data. Data collection We analysed case records from all agencies, interviewed professionals and invited parents to complete the Hospital Anxiety and Depression Scale (HADS) and questionnaires or in-depth interviews. Results Nearly all bereaved parents were able to understand the cause of death and several SIDS parents had a good understanding of the relevant modifiable risk factors even when these related directly to their actions. Paediatricians worried that discussing risk factors with parents would result in parental self-blame and some deliberately avoided these discussions. Over half the families did not mention blame or blamed no one. The cause of death of the infants of these families varied. 3/21 mothers expressed overwhelming feelings of self-blame and had clinically significant scores on HADS. Conclusions Bereaved parents want detailed information about their child's death. Our study

  6. Runtime and Inversion Impacts on Estimation of Moisture Retention Relations by Centrifuge

    NASA Astrophysics Data System (ADS)

    Sigda, J. M.; Wilson, J. L.

    2003-12-01

    Standard laboratory methods in soil physics for measuring the moisture retention relation (drainage matric potential-volumetric moisture content relation) are each limited to only part of the moisture content range. Centrifuge systems allow intensive accurate measurements across much of the saturation range, and typically require much less time than traditional laboratory methods. An initially liquid-saturated sample is subjected to a stepwise-increasing series of angular velocities while carefully monitoring changes in liquid content. Angular velocity is held constant until the capillary and centrifugal forces equilibrate, forcing liquid flux to zero, and then a final average liquid content is noted. The procedure is repeated after increasing the angular velocity. Centrifuge measurement time is greatly reduced because the centrifugal body force gradient can far exceed the driving forces utilized in standard lab methods. Widely-used in the petroleum industry for decades, centrifuge measurement of moisture retention relations is seldom encountered in the soil physics or vadose hydrology literatures. Yet there is a need to better understand and improve the experimental methodology given the increasing number of centrifuges employed in these fields. Errors in centrifuge measurement of moisture retention relations originate from both experimental protocol and from data inversion. Like standard methods, centrifuge methods assume equilibrium conditions, and so are sensitive to errors introduced by insufficient runtimes. Unlike standard methods, centrifuge experiments require inversion of the angular velocity and average sample moisture content data to a location-specific pair of matric potential and moisture content values, The force balance causes matric potential and moisture content to vary with sample length while the sample is spinning. Numerous data inversion techniques exist, each yielding different moisture retention relations. We present analyses demonstrating

  7. Embodied understanding

    PubMed Central

    Johnson, Mark

    2015-01-01

    Western culture has inherited a view of understanding as an intellectual cognitive operation of grasping of concepts and their relations. However, cognitive science research has shown that this received intellectualist conception is substantially out of touch with how humans actually make and experience meaning. The view emerging from the mind sciences recognizes that understanding is profoundly embodied, insofar as our conceptualization and reasoning recruit sensory, motor, and affective patterns and processes to structure our understanding of, and engagement with, our world. A psychologically realistic account of understanding must begin with the patterns of ongoing interaction between an organism and its physical and cultural environments and must include both our emotional responses to changes in our body and environment, and also the actions by which we continuously transform our experience. Consequently, embodied understanding is not merely a conceptual/propositional activity of thought, but rather constitutes our most basic way of being in, and engaging with, our surroundings in a deep visceral manner. PMID:26175701

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

    SciTech Connect

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

    1995-08-01

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

  9. Contribution of long-term hydrothermal experiments for understanding the smectite-to-chlorite conversion in geological environments

    NASA Astrophysics Data System (ADS)

    Mosser-Ruck, Régine; Pignatelli, Isabella; Bourdelle, Franck; Abdelmoula, Mustapha; Barres, Odile; Guillaume, Damien; Charpentier, Delphine; Rousset, Davy; Cathelineau, Michel; Michau, Nicolas

    2016-11-01

    The smectite-to-chlorite conversion is investigated through long-duration experiments (up to 9 years) conducted at 300 °C. The starting products were the Wyoming bentonite MX80 (79 % smectite), metallic iron and magnetite in contact with a Na-Ca chloride solution. The predominant minerals in the run products were an iron-rich chlorite (chamosite like) and interstratified clays interpreted to be chlorite/smectite and/or corrensite/smectite, accompanied by euhedral crystals of quartz, albite and zeolite. The formation of pure corrensite was not observed in the long-duration experiments. The conversion of smectite into chlorite over time appears to take place in several steps and through several successive mechanisms: a solid-state transformation, significant dissolution of the smectite and direct precipitation from the solution, which is over-saturated with respect to chlorite, allowing the formation of a chamosite-like mineral. The reaction mechanisms are confirmed by X-ray patterns and data obtained on the experimental solutions (pH, contents of Si, Mg, Na and Ca). Because of the availability of some nutrients in the solution, total dissolution of the starting smectite does not lead to 100 % crystallization of chlorite but to a mixture of two dominant clays: chamosite and interstratified chlorite/smectite and/or corrensite/smectite poor in smectite. The role of Fe/(Fe + Mg) in the experimental medium is highlighted by chemical data obtained on newly formed clay particles alongside previously published data. The newly formed iron-rich chlorite has the same composition as that predicted by the geothermometer for diagenetic to low-grade metamorphic conditions, and the quartz + Fe-chlorite + albite experimental assemblage in the 9-year experiment is close to that fixed by water-rock equilibrium.

  10. Improved understanding of the dynamic response in anisotropic directional composite materials through the combination of experiments and modeling

    NASA Astrophysics Data System (ADS)

    Alexander, C. S.; Key, C. T.; Schumacher, S. C.

    2014-05-01

    Recently there has been renewed interest in the dynamic response of composite materials; specifically low density epoxy matrix binders strengthened with continuous reinforcing fibers. This is in part due to the widespread use of carbon fiber composites in military, commercial, industrial, and aerospace applications. The design community requires better understanding of these materials in order to make full use of their unique properties. Planar impact testing was performed resulting in pressures up to 15 GPa on a unidirectional carbon fiber - epoxy composite, engineered to have high uniformity and low porosity. Results illustrate the anisotropic nature of the response under shock loading. Along the fiber direction, a two-wave structure similar to typical elastic-plastic response is observed, however, when shocked transverse to the fibers, only a single bulk shock wave is detected. At higher pressures, the epoxy matrix dissociates resulting in a loss of anisotropy. Greater understanding of the mechanisms responsible for the observed response has been achieved through numerical modeling of the system at the micromechanical level using the CTH hydrocode. From the simulation results it is evident that the observed two-wave structure in the longitudinal fiber direction is the result of a fast moving elastic precursor wave traveling in the carbon fibers ahead of the bulk response in the epoxy resin. Similarly, in the transverse direction, results show a collapse of the resin component consistent with the experimental observation of a single shock wave traveling at speeds associated with bulk carbon. Experimental and simulation results will be discussed and used to show where additional mechanisms, not fully described by the currently used models, are present.

  11. A curious experiment: the paradigm switch from observation and speculation to experimentation, in the understanding of neuromuscular function and disease.

    PubMed

    Pearn, John

    2002-08-01

    The four-link chain of the motor unit represents the contemporary end-point of some two millennia of evolving knowledge in neuroscience. The paradigm shift in neuromuscular epistemology occurred in the mid-17th century. In 1666, the newly graduated Dutch doctor, Jan Swammerdam (1637-1680) published his former investigations of dissected nerve-muscle preparations. These experiments comprised the quantum leap from observation and speculation, to that of experimentation in the field of neuroanatomy and neurophysiology. In what he termed 'A Curious Experiment' he also described the phenomenon of intrinsic muscle excitability - "I cannot observe that the muscle in the living animal ever absolutely ceases from all motion". Eighty years later (1752), von Haller demonstrated experimentally that irritability (contractility) was an intrinsic property of all muscular tissue; and distinguished between the sensibility of nerve impulses and the irritability of muscular contraction. This experimental progression from Swammerdam to von Haller culminated in 1850, when Claude Bernard's studies in experimental pharmacology confirmed that muscle was a functional unit, independent of any electrical innervation via its supplying nerve. This account comprises an audit of Swammerdam's work in the perspective of neuromuscular knowledge.

  12. Double Shock Experiments and Reactive Flow Modeling on LX-17 to Understand the Reacted Equation of State

    NASA Astrophysics Data System (ADS)

    Vandersall, Kevin; Garcia, Frank; Fried, Laurence; Tarver, Craig

    2013-06-01

    Experimental data from measurements of the reacted state of an energetic material are desired to incorporate reacted states in modeling by computer codes. In a case such as LX-17 (92.5% TATB and 7.5% Kel-F by weight), where the time dependent kinetics of reaction is still not fully understood and the reacted state may evolve over time, this information becomes even more vital. Experiments were performed to measure the reacted state of LX-17 using a double shock method involving the use of two flyer materials (with known properties) mounted on the projectile that send an initial shock through the material close to or above the Chapman-Jouguet (CJ) state followed by a second shock at a higher magnitude into the detonated material. By measuring the parameters of the first and second shock waves, information on the reacted state can be obtained. The LX-17 detonation reaction zone profiles plus the arrival times and amplitudes of reflected shocks in LX-17 detonation reaction products were measured using Photonic Doppler Velocimetry (PDV) probes and an aluminum foil coated LiF window. A discussion of this work will include the experimental parameters, velocimetry profiles, data interpretation, reactive CHEETAH and Ignition and Growth modeling, as well as possible future experiments. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  13. Double shock experiments and reactive flow modeling on LX-17 to understand the reacted equation of state

    NASA Astrophysics Data System (ADS)

    Vandersall, Kevin S.; Garcia, Frank; Fried, Laurence E.; Tarver, Craig M.

    2014-05-01

    Experimental data from measurements of the reacted state of an energetic material are desired to incorporate reacted states in modeling by computer codes. In a case such as LX-17 (92.5% TATB and 7.5% Kel-F by weight), where the time dependent kinetics of reaction is still not fully understood and the reacted state may evolve over time, this information becomes even more vital. Experiments were performed to measure the reacted state of LX-17 using a double shock method involving the use of two flyer materials (with known properties) mounted on the projectile that send an initial shock through the material close to or above the Chapman-Jouguet (CJ) state followed by a second shock at a higher magnitude into the detonated material. By measuring the parameters of the first and second shock waves, information on the reacted state can be obtained. The LX-17 detonation reaction zone profiles plus the arrival times and amplitudes of reflected shocks in LX-17 detonation reaction products were measured using Photonic Doppler Velocimetry (PDV) probes and an aluminum foil coated LiF window. A discussion of this work will include the experimental parameters, velocimetry profiles, data interpretation, reactive CHEETAH and Ignition and Growth modeling, as well as detail on possible future experiments.

  14. Timeslice experiments for understanding regional climate projections: applications to the tropical hydrological cycle and European winter circulation

    NASA Astrophysics Data System (ADS)

    Chadwick, Robin; Douville, Hervé; Skinner, Christopher B.

    2017-01-01

    A set of atmosphere-only timeslice experiments are described, designed to examine the processes that cause regional climate change and inter-model uncertainty in coupled climate model responses to CO_2 forcing. The timeslice experiments are able to reproduce the pattern of regional climate change in the coupled models, and are applied here to two cases where inter-model uncertainty in future projections is large: the tropical hydrological cycle, and European winter circulation. In tropical forest regions, the plant physiological effect is the largest cause of hydrological cycle change in the two models that represent this process. This suggests that the CMIP5 ensemble mean may be underestimating the magnitude of water cycle change in these regions, due to the inclusion of models without the plant effect. SST pattern change is the dominant cause of precipitation and circulation change over the tropical oceans, and also appears to contribute to inter-model uncertainty in precipitation change over tropical land regions. Over Europe and the North Atlantic, uniform SST increases drive a poleward shift of the storm-track. However this does not consistently translate into an overall polewards storm-track shift, due to large circulation responses to SST pattern change, which varies across the models. Coupled model SST biases influence regional rainfall projections in regions such as the Maritime Continent, and so projections in these regions should be treated with caution.

  15. Covert Retrieval Practice Benefits Retention as Much as Overt Retrieval Practice

    ERIC Educational Resources Information Center

    Smith, Megan A.; Roediger, Henry L., III; Karpicke, Jeffrey D.

    2013-01-01

    Many experiments provide evidence that practicing retrieval benefits retention relative to conditions of no retrieval practice. Nearly all prior research has employed retrieval practice requiring overt responses, but a few experiments have shown that covert retrieval also produces retention advantages relative to control conditions. However,…

  16. Structured Opportunities: Exploring the Social and Academic Benefits for Peer Mentors in Retention Programs

    ERIC Educational Resources Information Center

    Kiyama, Judy Marquez; Luca, Sandra Guillen

    2014-01-01

    Informed by the experiences of former peer mentors, this qualitative study examines the structure of opportunity of a university retention program. Extending the concept of social capital, the study investigates the experiences of students who served as peer mentors, and how their involvement in the retention program has influenced their social…

  17. Data Retention and Anonymity Services

    NASA Astrophysics Data System (ADS)

    Berthold, Stefan; Böhme, Rainer; Köpsell, Stefan

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

  18. Retention and Migration of Chlorpyrifos in Aquatic Sediments and Soils

    NASA Astrophysics Data System (ADS)

    Gebremariam, S. Y.; Beutel, M.; Yonge, D.; Flury, M.; Harsh, J. B.

    2010-12-01

    The accurate description of the fate and transport of potentially toxic agricultural pesticides in sediments and soils is of great interest to environmental scientists and regulators. Of particular concern is the widely documented detection of agricultural pesticides and their byproducts in drinking water wells. This presentation discusses results of a study of the fate and transport of chlorpyrifos, a strongly hydrophobic organophosphate-pesticide, in sediments and soils collected from a range of aquatic environments. Using radio-labeled chlorpyrifos, this study is unique in its comprehensive nature and focus on aquatic sediments, for which studies involving pesticide fate and transport are limited. Study components include: (1) batch equilibrium experiments to evaluate sorption/desorption parameters; (2) kinetic and non-equilibrium sorption experiments using miniaturized flow-cells; (3) column experiments to understand patterns of pesticide break through; and (4) numerical modeling of chlorpyrifos transport through aquatic sediments and soils. Initial results show that chlorpyrifos sorption, when corrected for reversible sorption to container walls, exhibited two component sorption, a large irreversible fraction and a smaller reversible fraction that can act as a secondary source. In addition, of a wide range of soil parameters measured, organic carbon content exhibited the highest correlation with chlorpyrifos retention in cranberry field soils. Simulation models developed in this study, which account for hysteretic and nonlinear sorption, will help to better predict the fate of chlorpyrifos and other hydrophobic chemicals in sediments and soils.

  19. Issues of International Student Retention in American Higher Education

    ERIC Educational Resources Information Center

    Bista, Krishna; Foster, Charlotte

    2011-01-01

    This paper focused on issues of retention and the individual needs of international students at a southern university through videotaped group interviews with six students from Africa, China, India, Japan, Jordan, and Nepal. Students were asked questions concerning their first experiences at the university, experiences out in the community,…

  20. Toward the understanding of hydration phenomena in aqueous electrolytes from the interplay of theory, molecular simulation, and experiment

    DOE PAGES

    Chialvo, Ariel A.; Vlcek, Lukas

    2015-05-22

    We confront the microstructural analysis of aqueous electrolytes and present a detailed account of the fundamentals underlying the neutron scattering with isotopic substitution (NDIS) approach for the experimental determination of ion coordination numbers in systems involving both halides anions and oxyanions. We place particular emphasis on the frequently overlooked ion-pairing phenomenon, identify its microstructural signature in the neutron-weighted distribution functions, and suggest novel techniques to deal with either the estimation of the ion-pairing magnitude or the correction of its effects on the experimentally measured coordination numbers. We illustrate the underlying ideas by applying these new developments to the interpretation ofmore » four NDIS test-cases via molecular simulation, as convenient dry runs for the actual scattering experiments, for representative aqueous electrolyte solutions at ambient conditions involving metal halides and nitrates.« less