High-resolution reflection spectroscopy

International Nuclear Information System (INIS)

Ducloy, Martial

1997-01-01

In this article some recent developments in selective reflection spectroscopy is reviewed and the various ways to extend Doppler free techniques to this spectroscopic field is discussed. Its main feature is to probe atomic gas close to the cell boundaries

Fullerene films and fullerene-dodecylamine adduct monolayers at air-water interfaces studied by neutron and x-ray reflection

DEFF Research Database (Denmark)

Wang, J.Y.; Vaknin, D.; Uphaus, R.A.

1994-01-01

Neutron and X-ray reflection measurements and surface pressure isotherms of spread films of the fullerene-dodecylamine adduct C60-[NH2(CH2)11CH3]x all indicate that this material may form monomolecular layers on water surfaces. The reflection data sets (neutron on both H2O and D2O) can be accounted...... for by a single model structure defined in terms of the dimensions of an average cell and its chemical composition. This model ascribes a total thickness of about 29 angstrom to the molecular interface layer with the following internal structure. The fullerenes (with several alkyl chains attached) form a central...... stratum and the remainder alkyl tails are located close to both the air and the water interfaces. The alkyl moieties close to the aqueous substrate are hydrated. The reflection experiments and the isotherms suggest that on average 8 +/- 3 dodecylamine molecules are present per fullerene, consistent within...

Parents and nurses balancing parent-infant closeness and separation: a qualitative study of NICU nurses' perceptions.

Science.gov (United States)

Feeley, Nancy; Genest, Christine; Niela-Vilén, Hannakaisa; Charbonneau, Lyne; Axelin, Anna

2016-08-20

When a newborn requires neonatal intensive care unit (NICU) hospitalization, parent and infant experience an unusual often prolonged separation. This critical care environment poses challenges to parent-infant closeness. Parents desire physical contact and holding and touching are particularly important. Evidence shows that visitation, holding, talking, and skin to skin contact are associated with better outcomes for infants and parents during hospitalization and beyond. Thus, it would be important to understand closeness in this context. The purpose of this study was to explore from nurses' perspective, what do parents and nurses do to promote parent-infant closeness or provoke separation. Qualitative methods were utilized to attain an understanding of closeness and separation. Following ethics approval, purposive sampling was used to recruit nurses with varying experience working different shifts in NICUs in two countries. Nurses were loaned a smartphone over one work shift to record their thoughts and perceptions of events that occurred or experiences they had that they considered to be closeness or separation between parents and their hospitalized infant. Sample size was determined by saturation (18 Canada, 19 Finland). Audio recordings were subjected to inductive thematic analysis. Team meetings were held to discuss emerging codes, refine categories, and confirm these reflected data from both sites. One overarching theme was elaborated. Balancing closeness and separation was the major theme. Both parents and nurses engaged in actions to optimize closeness. They sought closeness by acting autonomously in infant caregiving, assuming decision-making for their infant, seeking information or skills, and establishing a connection in the face of separation. Parents balanced their desire for closeness with other competing demands, such as their own needs. Nurses balanced infant care needs and ability to handle stimulation with the need for closeness with parents

Views of Nursing Students about Reflection: A Qualitative Study

Directory of Open Access Journals (Sweden)

Marrzieh Moattari

2009-06-01

Full Text Available Background and purpose: The phenomenon of knowledge explosion has led teachers to feel the necessity of training students so that they become reflective thinkers. This issue is particularly important for nursing students who are responsible for providing care for patients. The purpose ofthis study is exploration of nursing students’ views on reflection on practice.Methods: Twenty senior nursing students participated in this study. They were asked to reflect on their clinical experiences for 10 weeks of their final clinical course. They were also asked to write their reflection in their weekly journals. The journals were studied by the researcher and appropriatefeedback was given to the student regarding their reflective writing. At the end of the clinical course, they were divided into 2 groups to participate in 2 separate focus group session and to discuss the issues regarding 9 proposed open – ended questions. The students’ responses were tape – recorded and a transcript was made and analyzed qualitatively. The data were coded and categorized. Then each category was named to elicit the related constructs.Results: Qualitative data analysis showed that refection as a learning strategy has impact on 5 different elements of teaching learning process: caring, thinking, theory practice integration, selfregulatory mechanisms and motivation.Conclusion: Nursing students evaluated their experience on reflection on practice as an effective and valuable strategy. They believe that reflection through 5 different but related elements make them to consolidate their learning and plan their future experiences. Four out of the five emergedconstructs in this study are very similar to elements of cyclic learning proposed by Kolb (1984 and are capable of being integrated into experiential learning cycle. Motivation can be integrated into this cycle. Based on the result of this study reflection is suggested to be integrated in Iranian nursing curriculum

Visual Thinking Strategies: Teachers' Reflections on Closely Reading Complex Visual Texts within the Disciplines

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Cappello, Marva; Walker, Nancy T.

2016-01-01

The authors offer a new perspective on close reading that uses a range of multimodal texts to capitalize on the visual nature of contemporary society and to support literacy within the academic disciplines. Specifically, a qualitative study explored teachers' perspectives on the use of Visual Thinking Strategies (VTS), a practice borrowed from…

Insight in schizophrenia: involvement of self-reflection networks?

Science.gov (United States)

van der Meer, Lisette; de Vos, Annerieke E; Stiekema, Annemarie P M; Pijnenborg, Gerdina H M; van Tol, Marie-José; Nolen, Willem A; David, Anthony S; Aleman, André

2013-11-01

Impaired insight is a common feature in psychosis and an important predictor of variables such as functional outcome, prognosis, and treatment adherence. A cognitive process that may underlie insight in psychosis is self-reflection, or the conscious evaluation of one's traits and characteristics. The current study aims to investigate the neural correlates of self-reflective processing and its relationship with insight in schizophrenia. Forty-seven schizophrenia patients and 21 healthy controls performed a self-reflection task in a functional magnetic resonance imaging (fMRI) scanner. The tasks comprised a self-reflection, close other-reflection, and a semantic (baseline) condition. Insight scores were obtained with the Schedule of Assessment of Insight Expanded. In addition, cognitive insight scores were obtained (Beck Cognitive Insight Scale [BCIS]). Schizophrenia patients demonstrated less activation in the posterior cingulate cortex in the self- and other-reflection conditions and less activation in the precuneus in the other-reflection condition compared with healthy controls. Better insight was associated with greater response in the inferior frontal gyrus, anterior insula, and inferior parietal lobule during self-reflection. In addition, better cognitive insight was associated with higher activation in ventromedial prefrontal cortex during self-reflection. In the current study, evidence for a relationship between self-reflection and insight in patients with schizophrenia was found in brain areas related to self-reflection, self/other distinction and source attribution. The findings support the rationale for a treatment that is currently under evaluation, which attempts to increase insight by enhancing self-reflection.

On the reflection point where light reflects to a known destination on quadratic surfaces.

Science.gov (United States)

Gonçalves, Nuno

2010-01-15

We address the problem of determining the reflection point on a specular surface where a light ray that travels from a source to a target is reflected. The specular surfaces considered are those expressed by a quadratic equation. So far, there is no closed form explicit equation for the general solution of this determination of the reflection point, and the usual approach is to use the Snell law or the Fermat principle whose equations are derived in multidimensional nonlinear minimizations. We prove in this Letter that one can impose a set of three restrictions to the reflection point that can impose a set of three restrictions that culminates in a very elegant formalism of searching the reflection point in a unidimensional curve in space. This curve is the intersection of two quadratic equations. Some applications of this framework are also discussed.

Reflective Self-Regenerative Systems Architecture Study

National Research Council Canada - National Science Library

Pu, Carlton; Blough, Douglas

2006-01-01

In this study, we develop the Reflective Self-Regenerative Systems (RSRS) architecture in detail, describing the internal structure of each component and the mutual invocations among the components...

Insight in Schizophrenia: Involvement of Self-Reflection Networks?

Science.gov (United States)

de Vos, Annerieke E.

2013-01-01

Background: Impaired insight is a common feature in psychosis and an important predictor of variables such as functional outcome, prognosis, and treatment adherence. A cognitive process that may underlie insight in psychosis is self-reflection, or the conscious evaluation of one’s traits and characteristics. The current study aims to investigate the neural correlates of self-reflective processing and its relationship with insight in schizophrenia. Methods: Forty-seven schizophrenia patients and 21 healthy controls performed a self-reflection task in a functional magnetic resonance imaging (fMRI) scanner. The tasks comprised a self-reflection, close other-reflection, and a semantic (baseline) condition. Insight scores were obtained with the Schedule of Assessment of Insight Expanded. In addition, cognitive insight scores were obtained (Beck Cognitive Insight Scale [BCIS]). Results: Schizophrenia patients demonstrated less activation in the posterior cingulate cortex in the self- and other-reflection conditions and less activation in the precuneus in the other-reflection condition compared with healthy controls. Better insight was associated with greater response in the inferior frontal gyrus, anterior insula, and inferior parietal lobule during self-reflection. In addition, better cognitive insight was associated with higher activation in ventromedial prefrontal cortex during self-reflection. Conclusion: In the current study, evidence for a relationship between self-reflection and insight in patients with schizophrenia was found in brain areas related to self-reflection, self/other distinction and source attribution. The findings support the rationale for a treatment that is currently under evaluation, which attempts to increase insight by enhancing self-reflection. PMID:23104865

Lung Morphological Changes in Closed Chest Injury (an experimental study

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A. M. Golubev

2012-01-01

Full Text Available Objective: to study lung morphological changes in a closed chest injury model in laboratory animals. Material and methods. Experiments were carried out in 30 male albino nonbred rats weighing 350—380 g. Closed chest injury was simulated, by exposing the chest of anesthetized rats to a 300-g metal cylinder falling from a height of 30 cm. The observation periods were 1, 3, 6, and 24 hours. Results. The signs of evident perivenular edema that was uncharas-teristic to acute respiratory distress syndrome induced by other causes are an important peculiarity of lung morphological changes in this experimental model of closed chest injury. Conclusion. The experimental studies clarified the pattern of lung morphological changes in the early period after closed chest injury. Key words: closed chest injury, pulmonary edema.

Reflection after teaching a lesson: Experiences of secondary school science teachers

Science.gov (United States)

Halstead, Melissa A.

Secondary science teachers spend most of their time planning, collaborating, and teaching, but spend little time reflecting after teaching a single lesson. The theoretical framework of the adult learning theory and the transformative learning theory was the basis of this study. This qualitative research study was conducted to understand the reflective experiences of secondary science educators after teaching a single or several lessons. The collection of data consisted of interviews from a group of purposefully selected secondary science teachers who met the criteria set forth by the researcher. Through a qualitative analysis of interviews and field notes, the researcher determined that the secondary science teachers in this study shared similar as well as different experiences regarding collaborative and individual reflection after teaching a single or several lessons. The findings from this study also suggested that secondary science educators prefer to collaboratively reflect and then reflect alone to allow for further thought. Additionally, a supportive school culture increases the secondary science teacher’s desire to engage in collaborative as well as individual reflection. The information from this study could be used to close the gaps that exist in the teacher professional development programs.

RADIAL VELOCITY STUDIES OF CLOSE BINARY STARS. XIV

International Nuclear Information System (INIS)

Pribulla, Theodor; Rucinski, Slavek M.; DeBond, Heide; De Ridder, Archie; Karmo, Toomas; Thomson, J. R.; Croll, Bryce; Ogloza, Waldemar; Pilecki, Bogumil; Siwak, Michal

2009-01-01

Radial velocity (RV) measurements and sine curve fits to the orbital RV variations are presented for 10 close binary systems: TZ Boo, VW Boo, EL Boo, VZ CVn, GK Cep, RW Com, V2610 Oph, V1387 Ori, AU Ser, and FT UMa. Our spectroscopy revealed two quadruple systems, TZ Boo and V2610 Oph, while three stars showing small photometric amplitudes, EL Boo, V1387 Ori, and FT UMa, were found to be triple systems. GK Cep is a close binary with a faint third component. While most of the studied eclipsing systems are contact binaries, VZ CVn and GK Cep are detached or semidetached double-lined binaries, and EL Boo, V1387 Ori, and FT UMa are close binaries of uncertain binary type. The large fraction of triple and quadruple systems found in this sample supports the hypothesis of formation of close binaries in multiple stellar systems; it also demonstrates that low photometric amplitude binaries are a fertile ground for further discoveries of multiple systems.

A study of the anti-reflection efficiency of natural nano-arrays of varying sizes

International Nuclear Information System (INIS)

Sun Mingxia; Liang Aiping; Zheng Yongmei; Watson, Gregory S; Watson, Jolanta A

2011-01-01

The dependence of optical reflectivity and wettability on the surface topography of 32 species of cicada wing membranes has been investigated using UV-visible spectrophotometry, contact angle measurements and environmental scanning electron microscopy. The nanoscale hexagonally close packed protrusions have been shown to exhibit an anti-reflection and in some cases an anti-wetting function. The parameters of the structures were measured to be 77-148 nm in diameter, 44-117 nm in spacing and 159-481 nm in height. The transmittance spectrum and static contact angles were measured. At a wavelength range of 500-2500 nm, only minor differences in the anti-reflection performance were observed for each cicada species ascribed to the mechanism of impedance matching between cuticle and air. The transmittance properties of cicada wings were altered successfully through the scanning probe microscope-based manipulation by reducing the protrusion height via the contact mode. A near linear dependence was found between a decrease in protuberance height and a resulting increase in reflectance intensity. A diversity of wettability was observed with contact angles varying from 56.5 0 to 146.0 0 . Both effects of anti-reflection and wettability are dependent on the height of protrusions. The anti-reflection is insensitive when the wavelength is larger than the lateral feature size of the nanostructure. The stronger hydrophobic properties are generally associated with a larger diameter, closer spacing and greater height of protrusions when the wing membrane is intact.

Close Reading and Creative Writing in Clinical Education: Teaching Attention, Representation, and Affiliation.

Science.gov (United States)

Charon, Rita; Hermann, Nellie; Devlin, Michael J

2016-03-01

Medical educators increasingly have embraced literary and narrative means of pedagogy, such as the use of learning portfolios, reading works of literature, reflective writing, and creative writing, to teach interpersonal and reflective aspects of medicine. Outcomes studies of such pedagogies support the hypotheses that narrative training can deepen the clinician's attention to a patient and can help to establish the clinician's affiliation with patients, colleagues, teachers, and the self. In this article, the authors propose that creative writing in particular is useful in the making of the physician. Of the conceptual frameworks that explain why narrative training is helpful for clinicians, the authors focus on aesthetic theories to articulate the mechanisms through which creative and reflective writing may have dividends in medical training. These theories propose that accurate perception requires representation and that representation requires reception, providing a rationale for teaching clinicians and trainees how to represent what they perceive in their clinical work and how to read one another's writings. The authors then describe the narrative pedagogy used at the College of Physicians and Surgeons of Columbia University. Because faculty must read what their students write, they receive robust training in close reading. From this training emerged the Reading Guide for Reflective Writing, which has been useful to clinicians as they develop their skills as close readers. This institution-wide effort to teach close reading and creative writing aims to equip students and faculty with the prerequisites to provide attentive, empathic clinical care.

Close Reading and Creative Writing in Clinical Education: Teaching Attention, Representation, and Affiliation

Science.gov (United States)

Charon, Rita; Hermann, Nellie; Devlin, Michael J.

2015-01-01

Medical educators increasingly have embraced literary and narrative means of pedagogy, such as the use of learning portfolios, reading works of literature, reflective writing, and creative writing, to teach interpersonal and reflective aspects of medicine. Outcomes studies of such pedagogies support the hypotheses that narrative training can deepen the clinician's attention to a patient and can help to establish the clinician's affiliation with patients, colleagues, teachers, and the self. In this article, the authors propose that creative writing in particular is useful in the making of the physician. Of the conceptual frameworks that explain why narrative training is helpful for clinicians, the authors focus on aesthetic theories to articulate the mechanisms through which creative and reflective writing may have dividends in medical training. These theories propose that accurate perception requires representation and that representation requires reception, providing a rationale for teaching clinicians and trainees how to represent what they perceive in their clinical work and how to read one another's writings. The authors then describe the narrative pedagogy used at the College of Physicians and Surgeons of Columbia University. Since faculty must read what their students write, they receive robust training in close reading. From this training emerged the Reading Guide for Reflective Writing, which has been useful to clinicians as they develop their skills as close readers. This institution-wide effort to teach close reading and creative writing aims to equip students and faculty with the pre-requisites to provide attentive, empathic clinical care. PMID:26200577

The Economic Dimension in China’s Foreign Relations: Reflections for China Studies in the Philippines

Directory of Open Access Journals (Sweden)

Tina S. Clemente

2017-12-01

Full Text Available This essay elucidates the economic dimension of China’s foreign relations in aid of gleaning critical reflections on how China Studies in the Philippines can better consider China’s development experience and the Philippines’ economic engagement with China. Whether Philippines-China relations are tense or warm, the discourse on bilateral ties is dominated by interrogations from the vantage points of international relations, diplomacy, politics, and security analysis, which feature peripheral content on economic analysis even when improving economic linkages is invoked as a focal point of relations. Meanwhile, existing economic studies that touch on the bilateral relations do not have the interdisciplinary or area studies approach that must underpin the analysis. Employing a qualitative research design that involves content analysis, key informant interviews, and comparative reflection, the essay begins with an overview of how China’s development strategy has shaped its foreign relations. The essay opens with a brief overview of how China’s development strategy evolved since 1 978. The next section focuses on innovations in foreign relations and China’s grand new initiatives. What follows is the section on China’s need for further development, which consists of a discussion on inclusive development issues and resource demand. The fourth section underscores insights for China Studies in the Philippines. The essay ends with closing remarks.

Neural Correlates of Reflection on Present and Past Selves in Autism Spectrum Disorder.

Science.gov (United States)

Cygan, Hanna B; Marchewka, Artur; Kotlewska, Ilona; Nowicka, Anna

2018-06-05

Previous studies indicate that autobiographical memory is impaired in individuals with autism spectrum disorder (ASD). Successful recollection of information referring to one's own person requires the intact ability to re-activate representation of the past self. In the current fMRI study we investigated process of conscious reflection on the present self, the past self, and a close-other in the ASD and typically developing groups. Significant inter-group differences were found in the Past-Self condition. In individuals with ASD, reflection on the past self was associated with additional engagement of the posterior cingulate and posterior temporal structures. We hypothesize that this enhanced activation of widely distributed neural network reflects substantial difficulties in processes of reflection on one's own person in the past.

Fluid-Structure Interaction Mechanisms for Close-In Explosions

Directory of Open Access Journals (Sweden)

Andrew B. Wardlaw Jr.

2000-01-01

Full Text Available This paper examines fluid-structure interaction for close-in internal and external underwater explosions. The resulting flow field is impacted by the interaction between the reflected explosion shock and the explosion bubble. This shock reflects off the bubble as an expansion that reduces the pressure level between the bubble and the target, inducing cavitation and its subsequent collapse that reloads the target. Computational examples of several close-in interaction cases are presented to document the occurrence of these mechanisms. By comparing deformable and rigid body simulations, it is shown that cavitation collapse can occur solely from the shock-bubble interaction without the benefit of target deformation. Addition of a deforming target lowers the flow field pressure, facilitates cavitation and cavitation collapse, as well as reducing the impulse of the initial shock loading.

Mathematics teachers’ reflective practice within the context of adapted lesson study

Directory of Open Access Journals (Sweden)

Barbara Posthuma

2012-11-01

Full Text Available There seems to be paucity of research in South Africa on mathematics teachers’ reflective practice. In order to study this phenomenon, the context of lesson study (in an adapted form was introduced to five mathematics teachers in a rural school in the Free State. The purpose was to investigate their reflective practice whilst they collaboratively planned mathematics lessons and reflected on the teaching of the lessons. Data were obtained through interviews, video-recorded lesson observations, field notes taken during the lesson study group meetings and document analyses (lesson plans and reflective writings. The adapted lesson study context provided a safe space for teachers to reflect on their teaching and they reported an increase in self-knowledge and finding new ways of teaching mathematics to learners. This finding has some potential value for planning professional learning programmes in which teachers are encouraged to talk about their classroom experiences, share their joys and challenges with one another and strive to build a community of reflective practitioners to enhance their learners’ understanding of mathematics.

The interaction between reflection and practice in the professional development of a secondary education science teachers: Case study

Science.gov (United States)

Vazquez Bernal, Bartolome

The work that we describe here is a case study of two secondary education science teachers about how action-oriented reflection and action itself interact, and their influence on professional development. The study was carried out from two different viewpoints: a study with a qualitative orientation on the one hand, using diverse data collection and analysis instruments, and collaborative action research on the other, to form the backbone of professional development. In our theoretical outline, we stress the concepts of reflection which sustain the theoretical-practical dialectic, and of complexity which is seen to be a progression hypothesis of central importance, and in which we distinguish three dimensions: technique, practice, and criticism. The reflection data collection instruments were the teacher's diaries and memos, transcriptions of the work group meetings, questionnaires, and interviews. For the classroom practice the ethnographic notes and extracts from the videotapes of the class sessions, and other documentary sources such. The fundamental instrument for data analysis, both for reflection and practice, was the System of Categories that includes six analytical frames: ideological, teacher education, psychological, contextual, epistemological, and curricular. We also used third-order instruments for the representation, such as complexity spheres for reflection and practice and the reflection-practice integration horizon, which allowed the evolution of the teachers to be viewed over the course of the two school years that the research lasted, as well as giving an overall representation of the integration of reflection and practice. The results showed the teachers to be in transition from a technical to a practical dimension, with both her reflection and her classroom practice in the process of becoming more complex, and with the two being closely integrated. It was also found that she had a hard core of obstacles impeding her professional development. We

Theory of relativistic radiation reflection from plasmas

Science.gov (United States)

Gonoskov, Arkady

2018-01-01

We consider the reflection of relativistically strong radiation from plasma and identify the physical origin of the electrons' tendency to form a thin sheet, which maintains its localisation throughout its motion. Thereby, we justify the principle of relativistic electronic spring (RES) proposed in [Gonoskov et al., Phys. Rev. E 84, 046403 (2011)]. Using the RES principle, we derive a closed set of differential equations that describe the reflection of radiation with arbitrary variation of polarization and intensity from plasma with an arbitrary density profile for an arbitrary angle of incidence. We confirm with ab initio PIC simulations that the developed theory accurately describes laser-plasma interactions in the regime where the reflection of relativistically strong radiation is accompanied by significant, repeated relocation of plasma electrons. In particular, the theory can be applied for the studies of plasma heating and coherent and incoherent emissions in the RES regime of high-intensity laser-plasma interaction.

Evaluation of ethical reflections in community healthcare: a mixed-methods study.

Science.gov (United States)

Söderhamn, Ulrika; Kjøstvedt, Helga Tofte; Slettebø, Åshild

2015-03-01

Ethical reflections over care practices are important. In order to be able to perform such reflections, healthcare professionals must learn to think critically about their care practice. The aim of this study was to evaluate whether an introduction to and practice in ethical reflections in community healthcare have consequences for the healthcare personnel's practice. A mixed-methods design was adopted with five focus group interviews and an electronic questionnaire based on results from the interviews. A total of 29 community healthcare personnel with experience in ethical reflections participated in the interviews. The electronic questionnaire was sent via email to 2382 employees in community healthcare services in 13 municipalities in southern part of Norway. The study was guided by the intentions of the Declaration of Helsinki and ethical standard principles and approved by the Norwegian Social Science Data Services. An introduction to and practice in performing ethical reflections brought about an ethical awareness with understanding and respect for both colleagues and patients. The leader had a key role. Lack of time was a hindrance for ethical reflections. Three factors could predict meaningful ethical reflections: higher age of personnel, higher percentage of employment and longer experience with ethical reflections. According to other studies, ethical reflections may enhance moral development of colleagues and their actions as advocates for the patients. A deepened ethical awareness, professional competency and sufficient time resources will guarantee proper caregiving. A supportive environment that prioritizes participation in reflection meetings is decisive. To practice ethical reflections will provide better care for patients. A challenge for the community healthcare system is to offer adequate positions that provide the personnel an opportunity to be involved as caregivers and to participate in ethical reflections. © The Author(s) 2014.

In-vivo studies of reflectance pulse oximeter sensor

Science.gov (United States)

Ling, Jian; Takatani, Setsuo; Noon, George P.; Nose, Yukihiko

1993-08-01

Reflectance oximetry can offer an advantage of being applicable to any portion of the body. However, the major problem of reflectance oximetry is low pulsatile signal level which prevents prolonged clinical application during extreme situations, such as hypothermia and vasoconstriction. In order to improve the pulsatile signal level of reflectance pulse oximeter and thus its accuracy, three different sensors, with the separation distances (SPD) between light emitting diode (LED) and photodiode being 3, 5, and 7 mm respectively, were studied on nine healthy volunteers. With the increase of the SPD, it was found that both the red (660 nm) and near-infrared (830 nm) pulsatile to average signal ratio (AC/DC) increased, and the standard deviations of (AC/DC)red/(AC/DC)infrared ratio decreased, in spite of the decrease of the absolute signal level. Further clinical studies of 3 mm and 7 mm SPD sensors on seven patients also showed that the (AC/DC)red/(AC/DC)infrared ratio measured by the 7 mm sensor were less disturbed than the 3 mm sensor during the surgery. A theoretical study based on the three-dimensional photon diffusion theory supports the experimental and clinical results. As a conclusion, the 7 mm sensor has the highest signal-to- noise ratio among three different sensors. A new 7 mm SPD reflectance sensor, with the increased number of LEDs around the photodiode, was designed to increase the AC/DC ratio, as well as to increase the absolute signal level.

Study on closed cycle MHD generation systems; Closed cycle MHD hatsuden system no kento

Energy Technology Data Exchange (ETDEWEB)

NONE

1988-03-01

The closed cycle noble gas MHD generation systems are surveyed and studied. The concept of closed cycle noble gas MHD generation is confirmed to extract high enthalpy, and now going into the engineering demonstration stage from the basic research stage. These systems have various characteristics. The highest working temperature is around 1,700 degrees C, which is close to that associated with the existing techniques. Use of helium or argon gas as the working fluid makes the system relatively free of various problems, e.g., corrosion. It can attain a much higher efficiency than the combined cycle involving gas turbine. It suffers less heat loss in the passages, is suitable for small- to medium-capacity power generation systems, and copes with varying load. The compact power generation passages decrease required size of the superconducting magnet. The technical problems to be solved include optimization of power generation conditions, demonstration of durability of the power generation passages, injection/recovery of the seed material, treatment of the working gas to remove molecular impurities, and development of heat exchangers serviceable at high temperature produced by direct combustion of coal. The conceptual designs of the triple combined system are completed. (NEDO)

Rational reflection coefficient and inverse scattering on the line

International Nuclear Information System (INIS)

Sabatier, P.C.

1983-01-01

Inverse scattering for the Schroedinger equation on the line is studied for reflection and transmission coefficients that satisfy the usual regularity conditions and are rational functions of k. The origin is still a particular point, but the potentials do not need to be cut at this point like in previous studies. Giving up this restriction corresponds to the existence of poles for both reflection coefficients in both upper and lower half k-planes. It is shown that the problem reduces to solving a linear algebraic system. A different algorithm, made of a sequence of Darboux-Backlund transforms, gives also the solution in closed form and enables to study separately modifications of both sides of the potential due to the introduction of poles. Thus it paves the way for approximation studies. Generalizations and particular problems will be studied in forthcoming papers

Thoughts on Reflection (Editorial

Directory of Open Access Journals (Sweden)

Denise Koufogiannakis

2010-06-01

Full Text Available There has been some acknowledgement in the published literature that reflection is a crucial element of the evidence based library and information practice (EBLIP model we have adopted (Booth 2004, 2006; Grant 2007; Helliwell 2007. As we work through a problem and try to incorporate the best available evidence into our decision making, reflection is required at several stages, including the very identification of the problem through to our assessment of the process itself and what we have learned in order to inform future practice. However, reflection and reflective writing have not fully been integrated into the process we espouse, and very little has been done to look more closely at this element of the model and how it can be integrated into professional learning.In a recently published research article, Sen (2010 confirms the relationship between reflection and several aspects of professional practice. These include critical review and decision making, two aspects that are tied closely to the evidence based process. Sen notes: Students were more likely to show evidence of learning, self‐development, the ability to review issues crucially, awareness of their own mental functions, ability to make decision [sic] and being empowered when they had mastered the art of reflective practice and the more deeply analytical reflective writing. (p.84 EBLIP (the journal tries to incorporate elements of reflection within the articles we publish. While we clearly believe in the need for our profession to do quality research and publish that research so that it can be accessible to practitioners, we also know that research cannot be looked at in isolation. Our evidence summaries are one way of reflecting critically on previously published research, and in the same vein, our classics bring older research studies back to the foreground. This work needs to continue to be discussed and looked at for its impact on our profession.More directly, the Using

An investigation of the structure of plasma produced by reflected shock waves

International Nuclear Information System (INIS)

Phillips, M.G.R.; Pugatschew, A.A.

1979-05-01

Space and time resolved measurements of electron density and temperature have been made in the reflected-shock plasma produced by a Mach 20 incident shock wave propagating in argon at an initial pressure of 1.5 Torr. The peak electron density was found to decrease away from the reflecting wall in such a way that the plasma was fairly uniform at all times. Close to the reflecting wall (0.2 cm away) the measured peak electron density was close to (i.e. about 20% lower than) the predicted equilibrium value but further away (1.0 cm) it was lower by a factor 4. Possible reasons for this discrepancy are discussed. Calculations of reflected-shock plasma structure based on incident shock structure are only partially supported by available experimental evidence

Adjustment of Sentinel-2 Multi-Spectral Instrument (MSI Red-Edge Band Reflectance to Nadir BRDF Adjusted Reflectance (NBAR and Quantification of Red-Edge Band BRDF Effects

Directory of Open Access Journals (Sweden)

David P. Roy

2017-12-01

Full Text Available Optical wavelength satellite data have directional reflectance effects over non-Lambertian surfaces, described by the bidirectional reflectance distribution function (BRDF. The Sentinel-2 multi-spectral instrument (MSI acquires data over a 20.6° field of view that have been shown to have non-negligible BRDF effects in the visible, near-infrared, and short wave infrared bands. MSI red-edge BRDF effects have not been investigated. In this study, they are quantified by an examination of 6.6 million (January 2016 and 10.7 million (April 2016 pairs of forward and back scatter reflectance observations extracted over approximately 20° × 10° of southern Africa. Non-negligible MSI red-edge BRDF effects up to 0.08 (reflectance units across the 290 km wide MSI swath are documented. A recently published MODIS BRDF parameter c-factor approach to adjust MSI visible, near-infrared, and short wave infrared reflectance to nadir BRDF-adjusted reflectance (NBAR is adapted for application to the MSI red-edge bands. The red-edge band BRDF parameters needed to implement the algorithm are provided. The parameters are derived by a linear wavelength interpolation of fixed global MODIS red and NIR BRDF model parameters. The efficacy of the interpolation is investigated using POLDER red, red-edge, and NIR BRDF model parameters, and is shown to be appropriate for the c-factor NBAR generation approach. After adjustment to NBAR, red-edge MSI BRDF effects were reduced for the January data (acquired close to the solar principal where BRDF effects are maximal and the April data (acquired close to the orthogonal plane for all the MSI red-edge bands.

Ethics reflection groups in community health services: an evaluation study.

Science.gov (United States)

Lillemoen, Lillian; Pedersen, Reidar

2015-04-17

Systematic ethics support in community health services in Norway is in the initial phase. There are few evaluation studies about the significance of ethics reflection on care. The aim of this study was to evaluate systematic ethics reflection in groups in community health (including nursing homes and residency), - from the perspectives of employees participating in the groups, the group facilitators and the service managers. The reflection groups were implemented as part of a research and development project. A mixed-methods design with qualitative focus group interviews, observations and written reports were used to evaluate. The study was conducted at two nursing homes, two home care districts and a residence for people with learning disabilities. Participants were employees, facilitators and service managers. The study was guided by ethical standard principles and was approved by the Norwegian Social Science Data Services. We found support for ethics reflection as a valuable measure to strengthen clinical practice. New and improved solutions, more cooperation between employees, and improved collaboration with patients and their families are some of the results. No negative experiences were found. Instead, the ethics reflection based on experiences and challenges in the workplace, was described as a win-win situation. The evaluation also revealed what is needed to succeed and useful tips for further development of ethics support in community health services. Ethics reflection groups focusing on ethical challenges from the participants' daily work were found to be significant for improved practice, collegial support and cooperation, personal and professional development among staff, facilitators and managers. Resources needed to succeed were managerial support, and anchoring ethics sessions in the routine of daily work.

Variation of MODIS reflectance and vegetation indices with viewing geometry and soybean development.

Science.gov (United States)

Breunig, Fábio M; Galvão, Lênio S; Formaggio, Antônio R; Epiphanio, José C N

2012-06-01

Directional effects introduce a variability in reflectance and vegetation index determination, especially when large field-of-view sensors are used (e.g., Moderate Resolution Imaging Spectroradiometer - MODIS). In this study, we evaluated directional effects on MODIS reflectance and four vegetation indices (Normalized Difference Vegetation Index - NDVI; Enhanced Vegetation Index - EVI; Normalized Difference Water Index - NDWI(1640) and NDWI(2120)) with the soybean development in two growing seasons (2004-2005 and 2005-2006). To keep the reproductive stage for a given cultivar as a constant factor while varying viewing geometry, pairs of images obtained in close dates and opposite view angles were analyzed. By using a non-parametric statistics with bootstrapping and by normalizing these indices for angular differences among viewing directions, their sensitivities to directional effects were studied. Results showed that the variation in MODIS reflectance between consecutive phenological stages was generally smaller than that resultant from viewing geometry for closed canopies. The contrary was observed for incomplete canopies. The reflectance of the first seven MODIS bands was higher in the backscattering. Except for the EVI, the other vegetation indices had larger values in the forward scattering direction. Directional effects decreased with canopy closure. The NDVI was lesser affected by directional effects than the other indices, presenting the smallest differences between viewing directions for fixed phenological stages.

Close relationship between fMRI signals and transient heart rate changes accompanying K-complex. Simultaneous EEG/fMRI study

International Nuclear Information System (INIS)

Kan, Shigeyuki; Koike, Takahiko; Miyauchi, Satoru; Misaki, Masaya

2009-01-01

Combining functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) allows the investigation of spontaneous activities in the human brain. Recently, by using this technique, increases in fMRI signal accompanying transient EEG activities such as sleep spindles and slow waves were reported. Although these fMRI signal increases appear to arise as a result of the neural activities being reflected in the EEG, when the influence of physiological activities upon fMRI signals are taken into consideration, it is highly controversial that fMRI signal increases accompanying transient EEG activities reflect actual neural activities. In the present study, we conducted simultaneous fMRI and polysomnograph recording of 18 normal adults, to study the effect of transient heart rate changes after a K-complex on fMRI signals. Significant fMRI signal increase was observed in the cerebellum, the ventral thalamus, the dorsal part of the brainstem, the periventricular white matter and the ventricle (quadrigeminal cistern). On the other hand, significant fMRI signal decrease was observed only in the right insula. Moreover, intensities of fMRI signal increase that was accompanied by a K-complex correlated positively with the magnitude of heart rate changes after a K-complex. Previous studies have reported that K-complex is closely related with sympathetic nervous activity and that the attributes of perfusion regulation in the brain differ during wakefulness and sleep. By taking these findings into consideration, our present results indicate that a close relationship exists between a K-complex and the changes in cardio- and neurovascular regulations that are mediated by the autonomic nervous system during sleep; further, these results indicate that transient heart rate changes after a K-complex can affect the fMRI signal generated in certain brain regions. (author)

Hearing Nurses' Voices through Reflection in Women's Studies.

Science.gov (United States)

Doran, Frances M.; Cameron, Catherine C.

1998-01-01

Analysis of reflective papers by nursing students in women's studies courses revealed these themes: women's ambivalence about feminism, raised consciousness, empowerment, and desire for change. The importance of women's studies to the female-dominated profession of nursing was stressed. (SK)

[Reflectance of sea ice in Liaodong Bay].

Science.gov (United States)

Xu, Zhan-tang; Yang, Yue-zhong; Wang, Gui-fen; Cao, Wen-xi; Kong, Xiang-peng

2010-07-01

In the present study, the relationships between sea ice albedo and the bidirectional reflectance distribution in Liaodong Bay were investigated. The results indicate that: (1) sea ice albedo alpha(lambda) is closely related to the components of sea ice, the higher the particulate concentration in sea ice surface is, the lower the sea ice albedo alpha(lambda) is. On the contrary, the higher the bubble concentration in sea ice is, the higher sea ice albedo alpha(lambda) is. (2) Sea ice albedo alpha(lambda) is similar to the bidirectional reflectance factor R(f) when the probe locates at nadir. The R(f) would increase with the increase in detector zenith theta, and the correlation between R(f) and the detector azimuth would gradually increase. When the theta is located at solar zenith 63 degrees, the R(f) would reach the maximum, and the strongest correlation is also shown between the R(f) and the detector azimuth. (3) Different types of sea ice would have the different anisotropic reflectance factors.

Student Reflection Papers on a Global Clinical Experience: A Qualitative Study.

Science.gov (United States)

Margolis, Carmi Z; Rohrbaugh, Robert M; Tsang, Luisa; Fleischer, Jennifer; Graham, Mark J; Kellett, Anne; Hafler, Janet P

Many of the 70,000 graduating US medical students [per year] have reported participating in a global health activity at some stage of medical school. This case study design provided a method for understanding the student's experience that included student's learning about culture, health disparities, exposure and reaction to a range of diseases actually encountered. The broad diversity of themes among students indicated that the GCE provided a flexible, personalized experience. We need to understand the student's experience in order to help design appropriate curricular experiences [and valid student assessment]. Our research aim was to analyze medical student reflection papers to understand how they viewed their Global Clinical Experience (GCE). A qualitative case study design was used to analyze student reflection papers. All 28 students who participated in a GCE from 2008-2010 and in 2014-2015 and submitted a reflection paper on completion of the GCE were eligible to participate in the study. One student did not submit a reflection paper and was not included in the study. All 27 papers were coded by paragraph for reflection and for themes. System of Care/Range of Care was mentioned most often, Aids to Adjustment Process was mentioned least. The theme, "Diseases," referred to any mention of a disease in the reflection papers, and 44 diseases were mentioned in the papers. The analysis for depth of reflection yielded the following data: Observation, 81/248 paragraphs; Observation and Interpretation, 130/248 paragraphs; and Observation, Interpretation, and Suggestions for change, 36/248 paragraphs; 9 reflection papers contained 27 separate accounts of a transformational experience. This study provided a method for understanding the student's experience that included student's learning about culture, health disparities, and exposure and reaction to a range of diseases actually encountered. The broad diversity of themes among students indicated that the GCE provided a

Students' Stories of Studying Abroad: Reflections upon Return

Science.gov (United States)

Costello, Jane

2015-01-01

Study abroad brings an enriching experience to students' academic and personal lives. This narrative essay relays two students' experiences with study abroad sojourns and touches upon their technology use during their study abroad as recounted in semi-structured interviews. Details of their cultural experiences and reflections thereof as well as…

Eye movements during the recollection of text information reflect content rather than the text itself

DEFF Research Database (Denmark)

Traub, Franziska; Johansson, Roger; Holmqvist, Kenneth

Several studies have reported that spontaneous eye movements occur when visuospatial information is recalled from memory. Such gazes closely reflect the content and spatial relations from the original scene layout (e.g., Johansson et al., 2012). However, when someone has originally read a scene....... Recollection was performed orally while gazing at a blank screen. Results demonstrate that participant’s gaze patterns during recall more closely reflect the spatial layout of the scene than the physical locations of the text. Memory data provide evidence that mental models representing either the situation...... description, the memory of the physical layout of the text itself might compete with the memory of the spatial arrangement of the described scene. The present study was designed to address this fundamental issue by having participants read scene descriptions that where manipulated to be either congruent...

Numerical Study on Critical Wedge Angle of Cellular Detonation Reflections

International Nuclear Information System (INIS)

Gang, Wang; Kai-Xin, Liu; De-Liang, Zhang

2010-01-01

The critical wedge angle (CWA) for the transition from regular reflection (RR) to Mach reflection (MR) of a cellular detonation wave is studied numerically by an improved space-time conservation element and solution element method together with a two-step chemical reaction model. The accuracy of that numerical way is verified by simulating cellular detonation reflections at a 19.3° wedge. The planar and cellular detonation reflections over 45°–55° wedges are also simulated. When the cellular detonation wave is over a 50° wedge, numerical results show a new phenomenon that RR and MR occur alternately. The transition process between RR and MR is investigated with the local pressure contours. Numerical analysis shows that the cellular structure is the essential reason for the new phenomenon and the CWA of detonation reflection is not a certain angle but an angle range. (fundamental areas of phenomenology(including applications))

Evaluation of seismic reflection data in the Davis and Lavender Canyons study area, Paradox Basin, Utah

International Nuclear Information System (INIS)

Kitcho, C.A.; Wong, I.G.; Turcotte, F.T.

1986-08-01

Seismic reflection data purchased from petroleum industry brokers and acquired through group speculative surveys were interpreted for information on the regional subsurface geologic structure and stratigraphy within and surrounding the Davis and Lavender Canyons study area in the Paradox Basin of southeastern Utah. Structures of interest were faults, folds, joints, and collapse structures related to salt dissolution. The seismic reflection data were used to interpret stratigraphy by identifying continuous and discontinuous reflectors on the seismic profiles. Thickening and thinning of strata and possible areas of salt flowage or dissolution could be identified from the seismic data. Identifiable reflectors included the tops of the Precambrian and Mississippian, a distinctive interbed close to the middle of the Pennsylvanian Paradox salt formation (probably the interval between Salt Cycles 10 and 13), and near the top of the Paradox salt. Of the 56 faults identified from the seismic reflection interpretation, 33 trend northwest, west-northwest, or west, and most affect only the deeper part of the stratigraphic section. These faults are part of the deep structural system found throughout the Paradox Basin, including the fold and fault belt in the northeast part of the basin. The faults bound basement Precambrian blocks that experienced minor activity during Mississippian and early Pennsylvanian deposition, and showed major displacement during early Paradox salt deposition as the Paradox Basin subsided. Based on the seismic data, most of these faults appear to have an upward terminus between the top of the Mississippian and the salt interbed reflector

Neutron reflectivity studies of ionomer blends

CERN Document Server

Gabrys, B J; Bucknall, D G; Vesely, D; Braiewa, R; Weiss, R A

2002-01-01

Preliminary results are presented of a neutron reflectivity study of the interfacial width between lithium- and zinc-sulphonated deuterated polystyrene with polycarbonate (PC). Both systems are partially miscible and exhibit an upper critical solution temperature behaviour. The interdiffusion in these systems was measured by annealing at a temperature above the glass-transition temperature of both polymers. The interfacial profiles obtained for these systems were described by symmetric Gaussian interfaces. No significant diffusion was observed. (orig.)

Fracture diagnostics with tube wave reflection logs

International Nuclear Information System (INIS)

Medlin, W.L.

1991-01-01

This paper reports on the Tube Wave Reflection Log (TWRL) which is acoustic logging method which provides information about the height, location and conductivity of hydraulically induced fractures behind perforated casing. The TWRL tool consists of a transmitter and closely spaced receiver. The transmitter is driven with a short, low frequency tone burst to generate long wavelength tube waves which are little attenuated in unperforated casing. They are partially reflected when they pass perforated intervals communicating with a hydraulically induced fracture. The tool listens for such reflections for 0.1 seconds following each excitation burst. As the tool is moved uphole at logging speed, the transmitter is excited at each foot of depth. VDL displays of the TWRL records provide reflection traces whose projections define the uppermost and lower-most perforations communicating with the fracture. The strength of the reflections depends on the ease of fluid flow into the fracture and thus, is an indicator of fracture conductivity

Using anonymized reflection to teach ethics: a pilot study.

Science.gov (United States)

Kyle, Gaye

2008-01-01

Anonymized reflection was employed as an innovative way of teaching ethics in order to enhance students' ability in ethical decision making during a Care of the Dying Patient and Family' module. Both qualitative and quantitative data were collected from the first two student cohorts who experienced anonymized reflection ( n = 24). The themes identified were the richness and relevance of scenarios, small-group work and a team approach to teaching. Students indicated that they preferred this style of teaching. This finding was verified by a postal questionnaire conducted four months later. The conclusions drawn from this study suggest that using anonymized reflection is an effective method for teaching ethics to nurses and indicates that learning about ethical issues in this way reduces uncertainties.

Activation of anterior insula during self-reflection.

Science.gov (United States)

Modinos, Gemma; Ormel, Johan; Aleman, André

2009-01-01

Functional neuroimaging studies have suggested activation of midline frontoparietal brain regions to be at the core of self-related processes. However, although some studies reported involvement of the insula, little attention has been paid to this region as forming part of the "self"-network. Using functional magnetic resonance imaging (fMRI), we aimed at replicating and extending previous studies by scanning subjects whilst reflecting upon their own personal qualities as compared to those of an acquaintance. A third condition with statements about general knowledge was used to control for attention, semantic processing and decision making processes. The results showed a significant effect of task in brain activity, consistent with previous findings, by which both person conditions recruited a common set of medial prefrontal and posterior regions, yet significant differences between self and other were found in the medial prefrontal cortex (MPFC) and the anterior cingulate cortex (ACC). Notably, significant neural activation in the left anterior insula was observed as uniquely associated with self-reflection. The results provide further evidence for the specific recruitment of anterior MPFC and ACC regions for self-related processing, and highlight a role for the insula in self-reflection. As the insula is closely connected with ascending internal body signals, this may indicate that the accumulation of changes in affective states that might be implied in self-processing may contribute to our sense of self.

Euclidean mirrors: enhanced vacuum decay from reflected instantons

Science.gov (United States)

Akal, Ibrahim; Moortgat-Pick, Gudrid

2018-05-01

We study the tunnelling of virtual matter–antimatter pairs from the quantum vacuum in the presence of a spatially uniform, time-dependent electric background composed of a strong, slow field superimposed with a weak, rapid field. After analytic continuation to Euclidean spacetime, we obtain from the instanton equations two critical points. While one of them is the closing point of the instanton path, the other serves as an Euclidean mirror which reflects and squeezes the instanton. It is this reflection and shrinking which is responsible for an enormous enhancement of the vacuum pair production rate. We discuss how important features of two different mechanisms can be analysed and understood via such a rotation in the complex plane. (a) Consistent with previous studies, we first discuss the standard assisted mechanism with a static strong field and certain weak fields with a distinct pole structure in order to show that the reflection takes place exactly at the poles. We also discuss the effect of possible sub-cycle structures. We extend this reflection picture then to weak fields which have no poles present and illustrate the effective reflections with explicit examples. An additional field strength dependence for the rate occurs in such cases. We analytically compute the characteristic threshold for the assisted mechanism given by the critical combined Keldysh parameter. We discuss significant differences between these two types of fields. For various backgrounds, we present the contributing instantons and perform analytical computations for the corresponding rates treating both fields nonperturbatively. (b) In addition, we also study the case with a nonstatic strong field which gives rise to the assisted dynamical mechanism. For different strong field profiles we investigate the impact on the critical combined Keldysh parameter. As an explicit example, we analytically compute the rate by employing the exact reflection points. The validity of the predictions

Molecular-state close-coupling theory including continuum states. I. Derivation of close-coupled equations

International Nuclear Information System (INIS)

Thorson, W.R.; Bandarage, G.

1988-01-01

We formulate a close-coupling theory of slow ion-atom collisions based on molecular (adiabatic) electronic states, and including the electronic continuum. The continuum is represented by packet states spanning it locally and constructed explicitly from exact continuum states. Particular attention is given to two fundamental questions: (1) Unbound electrons can escape from the local region spanned by the packet states. We derive close-coupled integral equations correctly including the escape effects; the ''propagator'' generated by these integral equations does not conserve probability within the close-coupled basis. Previous molecular-state formulations including the continuum give no account of escape effects. (2) Nonadiabatic couplings of adiabatic continuum states with the same energy are singular, reflecting the fact that an adiabatic description of continuum behavior is not valid outside a local region. We treat these singularities explicitly and show that an accurate representation of nonadiabatic couplings within the local region spanned by a set of packet states is well behaved. Hence an adiabatic basis-set description can be used to describe close coupling to the continuum in a local ''interaction region,'' provided the effects of escape are included. In principle, the formulation developed here can be extended to a large class of model problems involving many-electron systems and including models for Penning ionization and collisional detachment processes

Observation on Surface Change of Fragile Glass: Temperature - Time Dependence Studied by X-Ray Reflectivity

International Nuclear Information System (INIS)

Kikkawa, Hiroyuki; Kitahara, Amane; Takahashi, Isao

2004-01-01

The structural change of a fragile glass surface close to the glass transition temperature Tg is studied by using X-ray reflectivity. Measurements were performed on surfaces of maltitol, which is a typical polyalcohol fragile glass with Tg = 320K. Upon both heating and cooling, we find the following features which are also noticed in silicate glass surfaces: (i) On heating, the surface morphology indicates a variation at temperatures below Tg; (ii) A drastic increase in surface roughness occurs at a temperature about 333K on heating, which is 13K higher than Tg; (iii) During the cooling of the sample, formation of a low-density surface layer (3nm at 293K) is observed. Prior to the crystallization, nm - μm sized domains were grown at the surface, which might not be reported for other glasses

Comparision of Incidental Reflection From Containerized Maintenance/Housekeeping Solutions and One Inch of Water

Energy Technology Data Exchange (ETDEWEB)

Chapman, Bryan Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); MacQuigg, Michael Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Wysong, Andrew Russell [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2016-12-15

This document addresses the incidental reflector reactivity worth of containerized maintenance/housekeeping fluids for use in PF-4 at Los Alamos National Laboratory (LANL). The intent of the document is to analyze containerized maintenance/housekeeping fluids which will be analyzed as water that may be present under normal conditions of an operation. The reactivity worth is compared to the reactivity worth due to I-inch of close-fitting 4n water reflection and I-inch of close-fitting radial water reflection. Both have been used to bound incidental reflection by 2-liter bottles in criticality safety evaluations. The conclusion is that, when the maintenance/housekeeping fluids are containerized the reactivity increase from a configuration which is bounding of normal conditions (up to eight bottles modeled with 2-liters of solution at varying diameter) is bound by I-inch of close fitting 4n water relection.

Metasurface-based anti-reflection coatings at optical frequencies

Science.gov (United States)

Monti, Alessio; Alù, Andrea; Toscano, Alessandro; Bilotti, Filiberto

2018-05-01

In this manuscript, we propose a metasurface approach for the reduction of electromagnetic reflection from an arbitrary air‑dielectric interface. The proposed technique exploits the exotic optical response of plasmonic nanoparticles to achieve complete cancellation of the field reflected by a dielectric substrate by means of destructive interference. Differently from other, earlier anti-reflection approaches based on nanoparticles, our design scheme is supported by a simple transmission-line formulation that allows a closed-form characterization of the anti-reflection performance of a nanoparticle array. Furthermore, since the working principle of the proposed devices relies on an average effect that does not critically depend on the array geometry, our approach enables low-cost production and easy scalability to large sizes. Our theoretical considerations are supported by full-wave simulations confirming the effectiveness of this design principle.

Euclidean mirrors. Enhanced vacuum decay from reflected instantons

Energy Technology Data Exchange (ETDEWEB)

Akal, Ibrahim [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany). Theory Group; Moortgat-Pick, Gudrid [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

2017-06-15

We study the tunneling of virtual matter-antimatter pairs from the quantum vacuum in the presence of a spatially uniform temporal electric background composed of of a strong slow field superimposed with a weak rapid field. After analytic continuation to Euclidean spacetime we obtain from the instanton equations two critical points. While one of them is the closing point of the instanton path, the other serves as an Euclidean mirror which reflects and squeezes the instanton. It is this reflection and shrinking which is responsible for an enormous enhancement of the vacuum pair production rate. We discuss how important features of this mechanism can be analysed and understood via such a rotation in the complex plane. Consistent with previous studies, we consider certain examples where we apply weak fields with a distinct pole structure in order to show that the reflection takes place exactly at the poles. We also discuss the effect of possible sub-cycle structures. We extend this reflection picture to fields which have no poles present and illustrate the effective reflections with explicit examples. An additional field strength dependence for the rate occurs in such cases. We analytically compute the characteristic threshold for this mechanism given by the critical combined Keldysh parameter. We discuss significant differences between these two types of fields. For various backgrounds, we present the contributing instantons and perform analytical computations for the corresponding rates treating both fields nonperturbatively. The validity of the results is confirmed by numerical computations. Considering different profiles for the strong field, we also discuss its impact on the critical combined Keldysh parameter.

Journaling: A quasi-experimental study of student nurses’ reflective learning ability

Directory of Open Access Journals (Sweden)

LP Fakude

2003-09-01

Full Text Available The use of journaling or journal writing in clinical education is one of the strategies used to develop critical thinking. Reflective journal writing, as it is commonly known, can nurture many qualities of a critical thinker and promote thoughtful nursing practice. Using a quasi-experimental design in this study, reflective journaling was introduced to a sample of first year Bridging Course student nurses at a Private Nursing Education Institution, to assess its effectiveness in reflective learning.

Raymond J. Chambers--A Personal Reflection

Science.gov (United States)

Gaffikin, Michael

2012-01-01

This paper is presented as a tribute to Raymond J. Chambers. As its title suggests, it is a personal reflection through the eyes of someone who worked closely with him over a period of 10 years during a latter part of his career, and who completed a doctoral thesis with aspects of the work of Chambers as its subject. During this time, author…

STUDY OF REFLECTION COEFFICIENT DISTRIBUTION FOR ANTI-REFLECTION COATINGS ON SMALL-RADIUS OPTICAL PARTS

Directory of Open Access Journals (Sweden)

L. A. Gubanova

2015-03-01

Full Text Available The paper deals with findings for the energy reflection coefficient distribution of anti- reflection coating along the surface of optical elements with a very small radius (2-12 mm. The factors influencing the magnitude of the surface area of the optical element, in which the energy reflection coefficient is constant, were detected. The main principles for theoretical models that describe the spectral characteristics of the multilayer interference coatings were used to achieve these objectives. The relative size of the enlightenment area is defined as the ratio of the radius for the optical element surface, where the reflection is less than a certain value, to its radius (ρ/r. The result of research is the following: this size is constant for a different value of the curvature radius for the optical element made of the same material. Its value is determined by the refractive index of material (nm, from which the optical element was made, and the design of antireflection coatings. For single-layer coatings this value is ρ/r = 0.5 when nm = 1.51; and ρ/r = 0.73 when nm = 1.75; for two-layer coatings ρ/r = 0.35 when nm = 1.51 and ρ/r = 0.41 when nm = 1.75. It is shown that with increasing of the material refractive index for the substrate size, the area of minimum reflection coefficient is increased. The paper considers a single-layer, two-layer, three-layer and five-layer structures of antireflection coatings. The findings give the possibility to conclude that equal thickness coverings formed on the optical element surface with a small radius make no equal reflection from the entire surface, and distribution of the layer thickness needs to be looked for, providing a uniform radiation reflection at all points of the spherical surface.

Disruption, Dialogue, and Swerve: Reflective Structured Dialogue in Religious Studies Classrooms

Science.gov (United States)

DeTemple, Jill; Sarrouf, John

2017-01-01

This article focuses on Reflective Structured Dialogue as a set of practices developed in the context of conflict resolution that are well suited to handling quotidian uneasiness and extraordinary moments of disruption in religious studies classrooms. After introducing Reflective Structured Dialogue's history, goals, and general practices, the…

Fisheries Closed Areas Strengthen Scallop Larval Settlement and Connectivity Among Closed Areas and Across International Open Fishing Grounds: A Model Study

Science.gov (United States)

Davies, Kimberley T. A.; Gentleman, W. C.; DiBacco, C.; Johnson, C. L.

2015-09-01

This study examined whether a measured increase in average body size of adult sea scallops inside three fishery closed areas on Georges Bank (GB), United States (US), was sufficient to increase larval supply to closed areas and open fishing areas in both US and Canadian areas of the Bank. The effects of adult scallop density-at-size and fecundity-at-size on egg production were compared among open and closed fishery areas, countries, and time periods before and after the closed areas were established. Estimated egg production was then used to define spawning conditions in a coupled biological-physical larval tracking model that simulated larval development, mortality, and dispersal. Results showed that order of magnitude increases in larval settlement after closure were facilitated by increases in size-dependant egg production inside and dispersal from Closed Areas I and II, but not Nantucket Lightship Closed Area. The distributions of both egg production and larval settlement became more uniform across the Bank, causing the relative contribution of Canadian larvae to US scallop aggregations to decrease after establishment of Closed Areas I and II. Decreases in small and medium-sized scallop density in Canada and decreases in large scallops over the US-Southern Flank after closure caused local declines in egg production but were not sufficient to negatively affect larval settlement at the regional scale. Our model suggests that the establishment of fishery closed areas on GB considerably strengthened larval supply and settlement within and among several adult scallop aggregations.

Activation of anterior insula during self-reflection.

Directory of Open Access Journals (Sweden)

Gemma Modinos

Full Text Available BACKGROUND: Functional neuroimaging studies have suggested activation of midline frontoparietal brain regions to be at the core of self-related processes. However, although some studies reported involvement of the insula, little attention has been paid to this region as forming part of the "self"-network. METHODOLOGY/PRINCIPAL FINDINGS: Using functional magnetic resonance imaging (fMRI, we aimed at replicating and extending previous studies by scanning subjects whilst reflecting upon their own personal qualities as compared to those of an acquaintance. A third condition with statements about general knowledge was used to control for attention, semantic processing and decision making processes. The results showed a significant effect of task in brain activity, consistent with previous findings, by which both person conditions recruited a common set of medial prefrontal and posterior regions, yet significant differences between self and other were found in the medial prefrontal cortex (MPFC and the anterior cingulate cortex (ACC. Notably, significant neural activation in the left anterior insula was observed as uniquely associated with self-reflection. CONCLUSIONS/SIGNIFICANCE: The results provide further evidence for the specific recruitment of anterior MPFC and ACC regions for self-related processing, and highlight a role for the insula in self-reflection. As the insula is closely connected with ascending internal body signals, this may indicate that the accumulation of changes in affective states that might be implied in self-processing may contribute to our sense of self.

Journaling: a quasi-experimental study of student nurses' reflective learning ability.

Science.gov (United States)

Fakude, L P; Bruce, J C

2003-08-01

The use of journaling or journal writing in clinical education is one of the strategies used to develop critical thinking. Reflective journal writing, as it is commonly known, can nurture many qualities of a critical thinker and promote thoughtful nursing practice. Using a quasi-experimental design in this study, reflective journaling was introduced to a sample of first year Bridging Course student nurses at a Private Nursing Education Institution, to assess its effectiveness in reflective learning. The study design enabled comparisons between two groups: one group of students assigned to do journaling (experimental group) and another group of students (control group) who did not journal. The students in the experimental group were given a period of eight weeks to journal their clinical experiences. At the end of this period, both groups were given an exercise, based on a clinical situation, to analyse reflectively and a comparison made on their performance. Descriptive statistics were used to analyse data and Fisher's Exact Test was used to determine the significance of differences observed within and between groups. The results showed that students in the experimental group performed better in exploring alternatives of action (p < 0.10) and formulating responses in similar future situations (p < 0.05) during the process of reflection. There was no significant difference between the groups' scores with regard to their ability to describe the clinical experience, to explore their related feelings, to evaluate the experience and to interpret/create meaning for themselves. Recommendations are made for continued student support and guidance during clinical education if reflection is considered to enhance reflective, thoughtful nursing practice.

Reflection of slow hydrogen and helium ions from solid surfaces

International Nuclear Information System (INIS)

Akkerman, A.F.

1978-01-01

Some characteristics of the proton and helium ion flux (E < 10 keV), reflected from solid surfaces are presented. A 'condensed walk' scheme, previously used for electron transport calculations, was adapted. Results obtained either by the scheme or by a more detailed 'consequent' scheme agreed closely. The presented data permit calculations of the mean energy of reflected particles and other values for various energy and angular distributions of incident particles. (author)

Studies of dust grain properties in infrared reflection nebulae.

Science.gov (United States)

Pendleton, Y J; Tielens, A G; Werner, M W

1990-01-20

We have developed a model for reflection nebulae around luminous infrared sources embedded in dense dust clouds. The aim of this study is to determine the sizes of the scattering grains. In our analysis, we have adopted an MRN-like power-law size distribution (Mathis, Rumpl, and Nordsieck) of graphite and silicate grains, but other current dust models would give results which were substantially the same. In the optically thin limit, the intensity of the scattered light is proportional to the dust column density, while in the optically thick limit, it reflects the grain albedo. The results show that the shape of the infrared spectrum is the result of a combination of the scattering properties of the dust, the spectrum of the illuminating source, and foreground extinction, while geometry plays a minor role. Comparison of our model results with infrared observations of the reflection nebula surrounding OMC-2/IRS 1 shows that either a grain size distribution like that found in the diffuse interstellar medium, or one consisting of larger grains, can explain the observed shape of the spectrum. However, the absolute intensity level of the scattered light, as well as the observed polarization, requires large grains (approximately 5000 angstroms). By adding water ice mantles to the silicate and graphite cores, we have modeled the 3.08 micrometers ice band feature, which has been observed in the spectra of several infrared reflection nebulae. We show that this ice band arises naturally in optically thick reflection nebulae containing ice-coated grains. We show that the shape of the ice band is diagnostic of the presence of large grains, as previously suggested by Knacke and McCorkle. Comparison with observations of the BN/KL reflection nebula in the OMC-1 cloud shows that large ice grains (approximately 5000 angstroms) contribute substantially to the scattered light.

Study on the effect of ambient gas on nanostructure formation on metal surfaces during femtosecond laser ablation for fabrication of low-reflective surfaces

Energy Technology Data Exchange (ETDEWEB)

Smausz, Tomi, E-mail: tomi@physx.u-szeged.hu [MTA-SZTE Research Group on Photoacoustic Spectroscopy, University of Szeged, 6720 Szeged, Dóm tér 9 (Hungary); Department of Optics and Quantum Electronics, University of Szeged, H-6720 Szeged, Dóm tér 9 (Hungary); Csizmadia, Tamás [Department of Optics and Quantum Electronics, University of Szeged, H-6720 Szeged, Dóm tér 9 (Hungary); Attosecond Light Pulse Source, ELI-Hu Nkft, H-6720 Szeged, Dugonics ter 13 (Hungary); Tápai, Csaba; Kopniczky, Judit [Department of Optics and Quantum Electronics, University of Szeged, H-6720 Szeged, Dóm tér 9 (Hungary); Oszkó, Albert [Department of Physical Chemistry and Material Science, University of Szeged, H-6720 Szeged, Aradi vértanuk tere 1 (Hungary); Ehrhardt, Martin; Lorenz, Pierre; Zimmer, Klaus; Prager, Andrea [Leibniz-Institut für Oberflächenmodifizierung e.V., Permoserstr. 15, 04318 Leipzig (Germany); Hopp, Béla [Department of Optics and Quantum Electronics, University of Szeged, H-6720 Szeged, Dóm tér 9 (Hungary)

2016-12-15

Highlights: • Metal surfaces were irradiated with femtosecond laser in different gas environments. • The reflectivity, morphology and chemical composition of the surfaces were studied. • Darkening was influenced by chemical and physical interaction of the plume and gas. • Molecular mass of the applied gas had an impact on the nanostructure formation. • For some of the used metals the oxide formation affected the reflective properties. - Abstract: Nanostructure formation on bulk metals (silver, gold, copper and titanium) by femtosecond Ti-sapphire laser irradiation (775 nm, 150 fs) is studied aiming the production of low-reflectivity surfaces and the better understanding of the development process. The experiments were performed in nitrogen, air, oxygen and helium environments at atmospheric pressure. The samples were irradiated with fluences in the 0.1–2 J/cm{sup 2} range and an average pulse number of 100 falling over a given area. The reflectivity of the treated surfaces was determined by a microspectrometer in the 450–800 nm range and their morphology was studied by scanning electron microscopy. The gas ambience influenced the results via two effects: formation processes and the chemically-induced modifications of the nanostructures. In case of He the nanoparticle aggregates–otherwise generally present–are predominantly missing, which leads to a lower darkening efficiency. The presence of oxygen enhances the darkening effect for copper mostly at lower fluences, while causes a slow increase in reflectivity in the case of titanium (in case of pure oxygen) in the high fluence range. The surface morphology in case of nitrogen and air were quite similar probably due to their close molecular mass values.

Reflections on the challenges and possibilities of journal publication in science education

Science.gov (United States)

Milne, Catherine; Siry, Christina; Mueller, Michael

2015-12-01

In this editorial we reflect on the intersections between the review and publishing policies of Cultural Studies of Science Education (CSSE) and the challenges and possibilities in global science education publishing. In particular we discuss the tensions associated with open or closed review policies, the hegemony of English as a language of publication, and reflect on some of the common challenges experienced by editors and authors from different contexts. We draw on the paper set in this issue consisting of five papers focused on publishing in various contexts, and elaborate several central questions for the field of science education and the dissemination of knowledges.

Roughness-reflectance relationship of bare desert terrain: An empirical study

International Nuclear Information System (INIS)

Shoshany, M.

1993-01-01

A study of the bidirectional reflectance distribution function (BRDF) in relation to surface roughness properties was conducted in arid land near Fowlers Gap Research Station, New South Wales, Australia. Such empirical study is necessary for investigating the possibility of determining terrain geomorphological parameters from bidirectional reflectance data. A new apparatus was developed to take accurate hemispherical directions radiance measurements (HDRM). A digitizer for three-dimensional in situ roughness measurements was also developed. More than 70 hemispherical data sets were collected for various illumination conditions and surface types of desert stony pavements and rocky terrain slopes. In general, it was found that most of the surfaces exhibited an anisotropic reflection, combining a major component of backscattering. The BRDF of different surface types in relation to their roughness properties as determined by the field digitizer were then examined. Results showed that sites that are considered to differ significantly from a geomorphological point of view would not necessarily form a different BRDF

Forsmark site investigation. Reflection seismic studies in the Forsmark area, 2004: Stage 2

Energy Technology Data Exchange (ETDEWEB)

Juhlin, Christopher; Palm, Hans [Uppsala Univ. (Sweden). Dept. of Earth Sciences

2005-06-15

Reflection seismic data were acquired in the Fall of 2004 in the Forsmark area, located about 140 km north of Stockholm, Sweden. The Forsmark area has been targeted by SKB as a possible storage site for spent nuclear fuel. About 25 km of high resolution (nominal source and receiver spacing of maximum 10 m and a minimum of 160 active channels) seismic data were acquired along 10 profiles, varying in length from about 1 km to over 4 km. Three of these profiles are extensions of profiles that were acquired in 2002 (Stage 1). While the 2002 Stage 1 profiles were geared towards acquiring data from within the relatively undeformed lens, the current study focused on acquiring data from the boundaries of the lens. Data acquisition was also concentrated towards the western part of the candidate area. Data were acquired using a combination of the same explosive source as in Stage 1 (1575 g of explosives) and the VIBSIST mechanical source consisting of an industrial hammer mounted on a tractor. Earlier tests in Laxemar had shown that the VIBSIST source gives comparable data to the explosive source and is less expensive. It can also be used in areas where explosives are prohibited, such as close to the nuclear power plant. At present, the source cannot be used in the terrain, therefore an explosive component is still required. About 80% of the 2100 source points were activated using the VIBSIST system. Stacked sections from the new profiles are generally consistent with the Stage 1 results. Reflections from the prominent south dipping A1 reflector can be observed on most profiles, however, it is not clear if it can be traced all the way to the surface. Neither is it clearly observed below the power plant, suggesting its lateral extent is limited to the west. Instead, a gently east dipping reflector (B8) is interpreted below the power plant. Reflections consistent with the A2 reflector are also found on two profiles, but cannot be traced very far to the south, suggesting that

Far infrared reflectivity study of ceramic superconductors

International Nuclear Information System (INIS)

Memon, A.; Khan, M.N.; Al-Dallal, S.; Tanner, D.B.; Porter, C.D.

1992-01-01

In this paper, the authors report on a study of the far-infrared reflectivity of mixed rare earths and lanthnides ceramic superconductors RBa 2 Cu 3 O 7 in the normal state. The authors' results show that the strength of the phonon modes is reduced when yttrium is partially replaced by gadolinium and europium. Also the critical temperature of these mixed materials is reduced as indicated by the four probe technique

REFLECTIVE PRACTICE THROUGH JOURNAL WRITING AND PEER OBSERVATION: A Case Study

Directory of Open Access Journals (Sweden)

B. Samrajya LAKSHMI

2014-10-01

Full Text Available Journal writing and Peer Observation in an educational context have become popular techniques, with several different types of applications. They have now been used quite widely in both language teaching and in teacher training. However, despite its reported advantages in both teaching and research, there are not many Peer Observation and Diary studies available based on the writing of experienced language teachers. The Teacher participants maintain Journal writing and Peer Observation as a means of reflective practice. They consider these practices as a mirror, which reflects the teacher’s own image as a practioner. The post-reflection discussion reveals that the teacher participants believe in reflective practice as an effective means of self-evaluation and of developing sensitivity to students’ learning. This paper examines Peer Observation and journal writing of two teachers working on the same language programme in terms of a variety of topic headings, and suggests that reflective practice can be a useful tool for both classroom research and teachers’ professional development.

The Close Relationships of People with Intellectual Disabilities: A Qualitative Study.

Science.gov (United States)

Sullivan, Faye; Bowden, Keith; McKenzie, Karen; Quayle, Ethel

2016-03-01

Positive interpersonal relationships have been found to enhance an individual's quality of life. However, people with intellectual disabilities (PWID) often have restricted social networks, and little is known about their views on close social relationships. The study aimed to explore how this group perceives and experiences close relationships. Ten (6 = men 4 = women) PWID participated. Data were collected using semi-structured interviews, and analysed using interpretive phenomenological analysis. The results report on three of five themes drawn from a larger qualitative study: 'Relationships feeling safe and being useful'; 'Who's in charge?' and 'Struggling for an ordinary life'. Close relationships are valued and desired by PWID, but a variety of barriers inhibit their development and maintenance. This includes the failure of others to value, accept and appropriately support the independence and relationships of PWID. Potential ways of addressing these issues are discussed. © 2015 John Wiley & Sons Ltd.

Neutron reflectivity studies of single lipid bilayers supported on planar substrates

International Nuclear Information System (INIS)

Krueger, S.; Orts, W.J.; Berk, N.F.; Majkrzak, C.F.; Koenig, B.W.

1994-01-01

Neutron reflectivity was used to probe the structure of single phosphatidylcholine (PC) lipid bilayers adsorbed onto a planar silicon surface in an aqueous environment. Fluctuations in the neutron scattering length density profiles perpendicular to the silicon/water interface were determined for different lipids as a function of the hydrocarbon chain length. The lipids were studied in both the gel and liquid crystalline phases by monitoring changes in the specularly-reflected neutron intensity as a function of temperature. Contrast variation of the neutron scattering length density was applied to both the lipid and the solvent. Scattering length density profiles were determined using both model-independent and model-dependent fitting methods. During the reflectivity measurements, a novel experimental set-up was implemented to decrease the incoherent background scattering due to the solvent. Thus, the reflectivity was measured to Q ∼ 0.3 Angstrom -1 , covering up to seven orders of magnitude in reflected intensity, for PC bilayers in D 2 O and silicon-matched (38% D 2 O/62% H 2 O) water. The kinetics of lipid adsorption at the silicon/water interface were also explored by observing changes in the reflectivity at low Q values under silicon-matched water conditions

Reflections around Artefacts: Using a Deliberative Approach to Teaching Reflective Practices in Fashion Studies

Science.gov (United States)

Ryan, Michael; Brough, Dean

2012-01-01

While requiring students to think reflectively is a desirable teaching goal, it is often fraught with complexity and is sometimes poorly implemented in higher education. In this paper, we describe an approach to academic reflective practices that fitted a design subject in fashion education and was perceived as effective in enhancing student…

Predicting foliar biochemistry of tea (Camellia sinensis) using reflectance spectra measured at powder, leaf and canopy levels

NARCIS (Netherlands)

Bian, B.M.; Skidmore, A.K.; Schlerf, M.; Wang, T.; Liu, X.; Zeng, R.; Fei, T.

2013-01-01

Some biochemical compounds are closely related with the quality of tea (Camellia sinensis (L.)). In this study, the concentration of these compounds including total tea polyphenols, free amino acids and soluble sugars were estimated using reflectance spectroscopy at three different levels: powder,

Reflective processes and competencies involved in teaching practice at university: a case study

Directory of Open Access Journals (Sweden)

Caetano da Costa

2010-01-01

Full Text Available Founded on practical rationality, this qualitative case study aimed to explore the teaching practice at university, focusing on teacher's reflections and competencies. To this end, teaching practices were described, analyzed, and interpreted. These interactions with students on a course in the pharmacy program, brought about situations involving dilemmas and learning opportunities for problem-solving and decision-making skills. Throughout the study, students were encouraged to use knowledge-in-action, reflection-in-action, and reflection-on-action, and these processes were also experienced by the teacher. Analysis of the records from classroom observation and the interviews with students and the teacher showed the fundamental role of such reflective processes, which led to attainment of the intended objectives. In this sense, the teacher's reflective practice was essential for supporting the application of each curricular component of the course.

A Study on Reflective Reciprocal Peer Coaching for Pre-Service Teachers: Change in Reflectivity

Science.gov (United States)

Gonen, S. Ipek Kuru

2016-01-01

Reflective practice is considered as an effective way for professional development in order to gain awareness of one's own teaching as well as to compete with the changing needs of the students. Especially in pre-service period, when pre-service teachers work cooperatively with their peers in a reciprocal fashion towards reflectivity, it has a…

Statistical eclipses of close-in Kepler sub-Saturns

Energy Technology Data Exchange (ETDEWEB)

Sheets, Holly A.; Deming, Drake, E-mail: hsheets@astro.umd.edu [Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)

2014-10-20

We present a method to detect small atmospheric signals in Kepler's planet candidate light curves by averaging light curves for multiple candidates with similar orbital and physical characteristics. Our statistical method allows us to measure unbiased physical properties of Kepler's planet candidates, even for candidates whose individual signal-to-noise precludes the detection of their secondary eclipse. We detect a secondary eclipse depth of 3.83{sub −1.11}{sup +1.10} ppm for a group of 31 sub-Saturn (R < 6 R {sub ⊕}) planet candidates with the greatest potential for a reflected light signature ((R{sub p} /a){sup 2} > 10 ppm). Including Kepler-10b in this group increases the depth to 5.08{sub −0.72}{sup +0.71} ppm. For a control group with (R{sub p} /a){sup 2} < 1 ppm, we find a depth of 0.36 ± 0.37 ppm, consistent with no detection. We also analyze the light curve of Kepler-10b and find an eclipse depth of 7.08 ± 1.06 ppm. If the eclipses are due solely to reflected light, this corresponds to a geometric albedo of 0.22 ± 0.06 for our group of close-in sub-Saturns, 0.37 ± 0.05 if including Kepler-10b in the group, and 0.60 ± 0.09 for Kepler-10b alone. Including a thermal emission model does not change the geometric albedo appreciably, assuming A{sub B} = (3/2)*A{sub g} . Our result for Kepler-10b is consistent with previous works. Our result for close-in sub-Saturns shows that Kepler-10b is unusually reflective, but our analysis is consistent with the results of Demory for super-Earths. Our results also indicate that hot Neptunes are typically more reflective than hot Jupiters.

Self-reflection modulates the outcome evaluation process: Evidence from an ERP study.

Science.gov (United States)

Zhu, Xiangru; Gu, Ruolei; Wu, Haiyan; Luo, Yuejia

2015-12-01

Recent research demonstrated structural overlap between reward and self processing, but the functional relationship that explains how self processing influences reward processing remains unclear. The present study used an experimentally constrained reflection task to investigate whether individuals' outcome evaluations in a gambling task are modulated by task-unrelated self- and other-reflection processes. The self- and other-reflection task contained descriptions of the self or others, and brain event-related potentials (ERPs) were recorded while 16 normal adults performed a gambling task. The ERP analysis focused on the feedback-related negativity (FRN) component. We found that the difference wave of FRN increased in the self-reflection condition compared with the other-reflection condition. The present findings provide direct evidence that self processing can influence reward processing. Copyright © 2015 Elsevier B.V. All rights reserved.

Issues in reflection and debriefing: how nurse educators structure experiential activities.

Science.gov (United States)

Brackenreg, Jenni

2004-12-01

Experiential learning is particularly useful in vocational education programs where theory needs to be linked to practice. Although experiential learning is often advocated in nursing education and the importance of debriefing and reflection is almost always espoused, the focus in the literature has tended to be on detailed descriptions of the action phase with little close analysis of how the reflective phase is facilitated. The Lewinian model described by Kolb [Experiential Learning. Experience as Source of Learning and Development, Prentice-Hall, New Jersey, 1984] and the structuring approach suggested by Thiagarajan [Experiential Learning Packages, Prentice-Hall, Englewood Cliffs, NJ, 1980] have been used as the theoretical context for an exploration of how nurse teachers describe their facilitation of the debriefing and reflective phases of experiential learning activities. Explication of the entire planned experiential learning experience is important for increasing the chances of the student being able to close the experiential learning loop. The more covert reflective phases for facilitating experiential learning are crucial and if neglected, or inexpertly and insensitively handled, may at best lead to poor learning outcomes or at worst lead to emotional damage and ;unfinished business' for the student. Interviews with eight experienced university educators elicited descriptions of how they constructed experiential activities with special reference to their descriptions of how the debriefing or reflective phases were structured.

Digital Storytelling as Poetic Reflection in Occupational Therapy Education: An Empirical Study

Directory of Open Access Journals (Sweden)

Lisebet S. Skarpaas

2016-07-01

Full Text Available Stories are powerful aids to reflection. Thus, the use of stories may be a pathway to enhanced reflective practice and clinical reasoning skills. The aim of this study was to evaluate whether and how digital storytelling can contribute to occupational therapy (OT students’ learning through reflections on experiences from placement education. A cohort of OT students (n = 57 participated in a 2-day workshop to create digital stories. Data were generated through a questionnaire with a response rate of 100% of students who completed the workshop (n = 34. Quantitative analysis methods were used to reveal a level of agreement in the questionnaire statements, and qualitative content analysis was performed for the open-ended questions. The results show that the students learned through reflection on placement experiences in the digital storytelling process as they emphasized reflection as a main outcome. They highlighted the importance of sharing thoughts and reflections with peers. The students confirmed that this happens through the creative process and the use of multimodality in poetic reflection, but they were less convinced by the use of the narrative approach as a dramatic structure. The students experienced reflection and sharing as important elements in the digital storytelling process. However, investigations are needed into the use of a narrative approach to enhance reflection with larger cohorts as well as more thematic analyses.

Self-reflection, growth goals, and academic outcomes: A qualitative study.

Science.gov (United States)

Travers, Cheryl J; Morisano, Dominique; Locke, Edwin A

2015-06-01

Goal-setting theory continues to be among the most popular and influential theories of motivation and performance, although there have been limited academic applications relative to applications in other domains, such as organizational psychology. This paper summarizes existing quantitative research and then employs a qualitative approach to exploring academic growth via an in-depth reflective growth goal-setting methodology. The study focuses on 92 UK final-year students enrolled in an elective advanced interpersonal skills and personal development module, with self-reflection and growth goal setting at its core. Qualitative data in the form of regular reflective written diary entries and qualitative questionnaires were collected from students during, on completion of, and 6 months following the personal growth goal-setting programme. About 20% of students' self-set growth goals directly related to academic growth and performance; students reported that these had a strong impact on their achievement both during and following the reflective programme. Growth goals that were indirectly related to achievement (e.g., stress management) appeared to positively impact academic growth and other outcomes (e.g., well-being). A follow-up survey revealed that growth goal setting continued to impact academic growth factors (e.g., self-efficacy, academic performance) beyond the reflective programme itself. Academic growth can result from both academically direct and indirect growth goals, and growth goal setting appears to be aided by the process of simultaneous growth reflection. The implications for promoting academic growth via this unique learning and development approach are discussed. © 2014 The British Psychological Society.

Three-dimensional particle tracking in concave structures made by ultraviolet nanoimprint via total internal reflection fluorescence microscopy and refractive-index-matching method

Science.gov (United States)

Fujinami, Taku; Kigami, Hiroshi; Unno, Noriyuki; Taniguchi, Jun; Satake, Shin-ichi

2018-03-01

Total internal reflection fluorescence microscopy (TIRFM) is a promising method for measuring fluid flow close to a wall with nanoscale resolution in a process that is termed "multilayer nanoparticle image velocimetry" (MnPIV). TIRFM uses evanescent light that is generated on a substrate (typically a glass slide) by total internal reflection of light. Many researchers have previously studied x-y-z (3D) flows of water close to flat glass slides using MnPIV. On the other hand, a fluid flow close to a structured surface is also important. To measure flows of water near micro-patterns, we previously developed an MnPIV technique that uses a refractive-index-matching method. In previous study, the micropattern is made of a thermoplastic material with a refractive index that closely matches that of water. In this study, ultraviolet nanoimprint lithography was used for fabricating the appropriate micro-patterns because this technique can fabricate a pattern with a high resolution. As a result, we succeeded in performing MnPIV in water with a circular hole array pattern made by ultraviolet nanoimprint using a refractive-index-matching method. We believe that this technique will be helpful in elucidating fluid flows around microstructures.

Neutron reflectivity studies of single lipid bilayers supported on planar substrates

Energy Technology Data Exchange (ETDEWEB)

Krueger, S.; Orts, W.J.; Berk, N.F.; Majkrzak, C.F. [National Inst. of Standards and Technology, Gaithersburg, MD (United States); Koenig, B.W. [National Inst. of Health, Bethesda, MD (United States)

1994-12-31

Neutron reflectivity was used to probe the structure of single phosphatidylcholine (PC) lipid bilayers adsorbed onto a planar silicon surface in an aqueous environment. Fluctuations in the neutron scattering length density profiles perpendicular to the silicon/water interface were determined for different lipids as a function of the hydrocarbon chain length. The lipids were studied in both the gel and liquid crystalline phases by monitoring changes in the specularly-reflected neutron intensity as a function of temperature. Contrast variation of the neutron scattering length density was applied to both the lipid and the solvent. Scattering length density profiles were determined using both model-independent and model-dependent fitting methods. During the reflectivity measurements, a novel experimental set-up was implemented to decrease the incoherent background scattering due to the solvent. Thus, the reflectivity was measured to Q {approx} 0.3{Angstrom}{sup -1}, covering up to seven orders of magnitude in reflected intensity, for PC bilayers in D{sub 2}O and silicon-matched (38% D{sub 2}O/62% H{sub 2}O) water. The kinetics of lipid adsorption at the silicon/water interface were also explored by observing changes in the reflectivity at low Q values under silicon-matched water conditions.

Return Stroke Current Reflections in Rocket-Triggered Lightning

Science.gov (United States)

Caicedo, J.; Uman, M. A.; Jordan, D.; Biagi, C. J.; Hare, B.

2015-12-01

In the six years from 2009 to 2014, there have been eight triggered flashes at the ICLRT, from a total of 125, in which a total of ten return stroke channel-base currents exhibited a dip 3.0 to 16.6 μs after the initial current peak. Close range electric field measurements show a related dip following the initial electric field peak, and electric field derivative measurements show an associated bipolar pulse, confirming that this phenomenon is not an instrumentation effect in the current measurement. For six of the eight flashes, high-speed video frames show what appears to be suspended sections of unexploded triggering wire at heights of about 150 to 300 m that are illuminated when the upward current wave reaches them. The suspended wire can act as an impedance discontinuity, perhaps as it explodes, and cause a downward reflection of some portion of the upward-propagating current wave. This reflected wave travels down the channel and causes the dip in the measured channel-base current when it reaches ground and reflects upward. The modified transmission line model with exponential decay (MTLE) is used to model the close electric field and electric field derivatives of the postulated initial and reflected current waves, starting with the measured channel base current, and the results are compared favorably with measurements made at distances ranging from 92 to 444 m. From the measured time between current impulse initiation and the time the current reflection reaches the channel base and the current dip initiates, along with the reflection height from the video records, we find the average return stroke current speed for each of the ten strokes to be from 0.28 to 1.9×108 ms-1, with an error of ±0.01×108 ms-1 due to a ±0.1 μs uncertainty in the measurement. This represents the first direct measurement of return stroke current speed, all previous return stroke speed measurements being derived from the luminosity of the process.

Leakage localization with an acoustic array that covers a wide area for pipeline leakage monitoring in a closed space

Energy Technology Data Exchange (ETDEWEB)

Park, Choon Su [Center for Safety Measurements, Division of Metrology for Quality of Life, Korea Research institute of Standards and Science, Daejeon (Korea, Republic of); Jeon, Jong Hoon [Hyundai Heavy Industry Co.,Ltd., Ulsan (Korea, Republic of); Park, Jin Ho [Korea Atomiv Energy Institute, Daejeon (Korea, Republic of)

2013-10-15

It is of great importance to localize leakages in complex pipelines for assuring their safety. A sensor array that can detect where leakages occur enables us to monitor a wide area with a relatively low cost. Beam forming is a fast and efficient algorithm to estimate where sources are, but it is generally made use of in free field condition. In practice, however, many pipelines are placed in a closed space for the purpose of safety and maintenance. This leads us to take reflected waves into account to the beam forming for interior leakage localization. Beam power distribution of reflected waves in a closed space is formulated, and spatial average is introduced to suppress the effect of reflected waves. Computer simulations and experiments ensure how the proposed method is effective to localize leakage in a closed space for structural health monitoring.

Developing Reflective Dispositions through Collaborative Knowledge-Building during Small Group Bible Study

Science.gov (United States)

Toh, Tze Keong; Koh, Joyce Hwee Ling; Chai, Ching Sing

2017-01-01

This article explores the use of a constructivist pedagogical approach to cultivate reflective dispositions during small group Bible study. Conducted in a local church Bible class setting (n = 12), the instructional design emulated the reflective thinking process, while adopting collaborative knowledge-building as its pedagogical framework.…

Ethics in Doctoral Studies: Reflections and Refractions from an ...

African Journals Online (AJOL)

Research ethics are the cornerstone of conducting effective and meaningful research. Selected theses by doctoral students show variations in ethical considerations applicable. This article discusses personal reflections and refractions in an experiential journey in which child-rearing practices of refugees were studied.

A multidisciplinary study of a small, temporarily open/closed South ...

African Journals Online (AJOL)

In 2005/2006 a multidisciplinary research programme that included studies on the hydrodynamics, sediment dynamics, macronutrients, microalgae, macrophytes, zoobenthos, hyperbenthos, zooplankton, ichthyoplankton, fish and birds of the temporarily open/closed East Kleinemonde Estuary was conducted. Particular ...

Ultrasonic examination of defects close to the outer surface

International Nuclear Information System (INIS)

Benoist, P.; Serre, M.; Champigny, F.

1986-11-01

During the examination of a pressurized water reactor vessel with an in Service Inspection Machine (MIS), various welds are scanned with immersion ultrasonic focused transducers from the inside of the vessel. Defects close to the outer surface are sometimes detected, and sizing with the successive 6 dB drop method leads to oversize some indications; this is caused by various reflections on the outer wall; the corner echo is of particular importance here. CEA and EDF have started an experimental program in order to study the response of volumetric and planar defects located near the outer surface. We present here the first results obtained with artificial defects. 2 refs

Some reflections on the history of particle physics in the 1950s

International Nuclear Information System (INIS)

Schweber, S.S.

1989-01-01

This paper reflects on the differences in attitude, area of study and type of physicist between those attending the Solvay conferences in 1948 and 1961. These reflect wider historical and political changes which affected high-energy particle physics in the nineteen fifties. The growth of the field reflected post-war funding on a huge scale to ensure adequate scientific manpower for military purposes. Large synchrocyclotrons and proton-synchrotrons were built and high-energy installations became widespread in universities. Theoreticians worked closely with experimentalists using a pragmatic utilitarian approach. Later military needs began to dictate funding allocation and many theoreticians worked on military as well as their own projects. This pragmatic, group approach became accepted world-wide as the way to ''do'' big science. The funding system, including peer-review, tended only to reinforce the dominant view of theorists as valuable accessories of experimentalists. (UK)

Reflective ability and moral reasoning in final year medical students: a semi-qualitative cohort study.

Science.gov (United States)

Chalmers, Patricia; Dunngalvin, Audrey; Shorten, George

2011-01-01

Moral reasoning and reflective ability are important concepts in medical education. To date, the association between reflective ability and moral reasoning in medical students has not been measured. This study tested the hypotheses that, amongst final year medical students, (1) moral reasoning and reflective ability improve over time and (2) positive change in reflective ability favourably influences moral reasoning. With Institutional Ethical approval, 56 medical students (of a class of 110) participated fully both at the beginning and end of the final academic year. Reflective ability and moral reasoning were assessed at each time using Sobral's reflection-in-learning scale (RLS), Boenink's overall reflection score and by employing Kohlberg's schema for moral reasoning. The most important findings were that (1) Students' level of reflective ability scores related to medicine decreased significantly over the course of the year, (2) students demonstrated a predominantly conventional level of moral reasoning at both the beginning and end of the year, (3) moral reasoning scores tended to decrease over the course of the year and (4) RLS is a strong predictor of change in moral reasoning over time. This study confirms the usefulness of Sobral's RLS and BOR score for evaluating moral development in the context of medical education. This study further documents regression and levelling in the moral reasoning of final year medical students and a decrease in reflective ability applied in the medical context. Further studies are required to determine factors that would favourably influence reflective ability and moral reasoning among final year medical students.

Reflecting reflection in supervision

DEFF Research Database (Denmark)

Lystbæk, Christian Tang

associated with reflection and an exploration of alternative conceptions that view reflection within the context of settings which have a more group- and team-based orientation. Drawing on an action research project on health care supervision, the paper questions whether we should reject earlier views...... of reflection, rehabilitate them in order to capture broader connotations or move to new ways of regarding reflection that are more in keeping with not only reflective but also emotive, normative and formative views on supervision. The paper presents a critical perspective on supervision that challenge...... the current reflective paradigm I supervision and relate this to emotive, normative and formative views supervision. The paper is relevant for Nordic educational research into the supervision and guidance...

Becoming Reflective Practitioners: A Case Study of Three Beginning Pre-Service Teachers

Science.gov (United States)

Tiainen, Outi; Korkeamäki, Riitta-Liisa; Dreher, Mariam Jean

2018-01-01

This case study examined three pre-service teachers' reflection processes during their first teaching practicum. During the six-week practicum, the pre-service teachers reflected on their own as well as their peers' teaching in group mentoring meetings several times a week. Unstructured stimulated recall facilitated pre-service teacher-initiated…

Measuring third year undergraduate nursing students' reflective thinking skills and critical reflection self-efficacy following high fidelity simulation: A pilot study.

Science.gov (United States)

Tutticci, Naomi; Lewis, Peter A; Coyer, Fiona

2016-05-01

Critical reflection underpins critical thinking, a highly desirable generic nursing graduate capability. To improve the likelihood of critical thinking transferring to clinical practice, reflective thinking needs to be measured within the learning space of simulation. This study was divided into two phases to address the reliability and validity measures of previously untested surveys. Phase One data was collected from individuals (n = 6) using a 'think aloud' approach and an expert panel to review content validity, and verbatim comment analysis was undertaken. The Reflective Thinking Instrument and Critical Reflection Self-Efficacy Visual Analogue Scale items were contextualised to simulation. The expert review confirmed these instruments exhibited content validity. Phase Two data was collected through an online survey (n = 58). Cronbach's alpha measured internal consistency and was demonstrated by all subscales and the Instrument as a whole (.849). There was a small to medium positive correlation between critical reflection self-efficacy and general self-efficacy (r = .324, n = 56, p = .048). Participant responses were positive regarding the simulation experience. The research findings demonstrated that the Reflective Thinking and Simulation Satisfaction survey is reliable. Further development of this survey to establish validity is recommended to make it viable. Copyright © 2016 Elsevier Ltd. All rights reserved.

Diffuse reflectance startigraphy - a new method in the study of loess (?)

Science.gov (United States)

József, Szeberényi; Balázs, Bradák; Klaudia, Kiss; József, Kovács; György, Varga; Réka, Balázs; Viczián, István

2017-04-01

The different varieties of loess (and intercalated paleosol layers) together constitute one of the most widespread terrestrial sediments, which was deposited, altered, and redeposited in the course of the changing climatic conditions of the Pleistocene. To reveal more information about Pleistocene climate cycles and/or environments the detailed lithostratigraphical subdivision and classification of the loess variations and paleosols are necessary. Beside the numerous method such as various field measurements, semi-quantitative tests and laboratory investigations, diffuse reflectance spectroscopy (DRS) is one of the well applied method on loess/paleosol sequences. Generally, DRS has been used to separate the detrital and pedogenic mineral component of the loess sections by the hematite/goethite ratio. DRS also has been applied as a joint method of various environmental magnetic investigations such as magnetic susceptibility- and isothermal remanent magnetization measurements. In our study the so-called "diffuse reflectance stratigraphy method" were developed. At First, complex mathematical method was applied to compare the results of the spectral reflectance measurements. One of the most preferred multivariate methods is cluster analysis. Its scope is to group and compare the loess variations and paleosol based on the similarity and common properties of their reflectance curves. In the Second, beside the basic subdivision of the profiles by the different reflectance curves of the layers, the most characteristic wavelength section of the reflectance curve was determined. This sections played the most important role during the classification of the different materials of the section. The reflectance value of individual samples, belonged to the characteristic wavelength were depicted in the function of depth and well correlated with other proxies like grain size distribution and magnetic susceptibility data. The results of the correlation showed the significance of the

Meteorological information in GPS-RO reflected signals

Directory of Open Access Journals (Sweden)

K. Boniface

2011-07-01

Full Text Available Vertical profiles of the atmosphere can be obtained globally with the radio-occultation technique. However, the lowest layers of the atmosphere are less accurately extracted. A good description of these layers is important for the good performance of Numerical Weather Prediction (NWP systems, and an improvement of the observational data available for the low troposphere would thus be of great interest for data assimilation. We outline here how supplemental meteorological information close to the surface can be extracted whenever reflected signals are available. We separate the reflected signal through a radioholographic filter, and we interpret it with a ray tracing procedure, analyzing the trajectories of the electromagnetic waves over a 3-D field of refractive index. A perturbation approach is then used to perform an inversion, identifying the relevant contribution of the lowest layers of the atmosphere to the properties of the reflected signal, and extracting some supplemental information to the solution of the inversion of the direct propagation signals. It is found that there is a significant amount of useful information in the reflected signal, which is sufficient to extract a stand-alone profile of the low atmosphere, with a precision of approximately 0.1 %. The methodology is applied to one reflection case.

Reflective processes of practitioners in head and neck cancer rehabilitation: a grounded theory study.

Science.gov (United States)

Caty, Marie-Ève; Kinsella, Elizabeth Anne; Doyle, Philip C

2016-12-01

This study systematically examined how experienced Speech-Language Pathologists (SLPs) use the processes of reflection to develop knowledge relevant for practice in the context of head and neck cancer (HNC) rehabilitation. In-depth, semi-structured interviews were conducted with 12 SLPs working in HNC rehabilitation in North America. Grounded theory methodology was adopted for data collection and analysis. The findings inform a preliminary reflective practice model that depicts the processes of reflection used by practitioners interviewed. Nine categories of reflective processes were identified by participant SLPs in terms of the processes of reflection: ongoing questioning, experimenting through trial and error, integrating knowledge from past cases, embracing surprise, thinking out of the box, being in the moment, consulting with colleagues, putting oneself in the patients' shoes, and discerning ethical issues. These findings provide empirical evidence that supports Schön's theory of reflective practice and contribute to knowledge about the ways in which SLPs use processes of reflection in the context of HNC rehabilitation. The findings of this study have implications for how SLPs perceive and consider their role as knowledge-users and knowledge producers in their day-to-day clinical work, as well as for building capacity for reflective practice.

TURBULENCE IN THE SUB-ALFVENIC SOLAR WIND DRIVEN BY REFLECTION OF LOW-FREQUENCY ALFVEN WAVES

International Nuclear Information System (INIS)

Verdini, A.; Velli, M.; Buchlin, E.

2009-01-01

We study the formation and evolution of a turbulent spectrum of Alfven waves driven by reflection off the solar wind density gradients, starting from the coronal base up to 17 solar radii, well beyond the Alfvenic critical point. The background solar wind is assigned and two-dimensional shell models are used to describe nonlinear interactions. We find that the turbulent spectra are influenced by the nature of the reflected waves. Close to the base, these give rise to a flatter and steeper spectrum for the outgoing and reflected waves, respectively. At higher heliocentric distance both spectra evolve toward an asymptotic Kolmogorov spectrum. The turbulent dissipation is found to account for at least half of the heating required to sustain the background imposed solar wind and its shape is found to be determined by the reflection-determined turbulent heating below 1.5 solar radii. Therefore, reflection and reflection-driven turbulence are shown to play a key role in the acceleration of the fast solar wind and origin of the turbulent spectrum found at 0.3 AU in the heliosphere.

Control of generation spectrum of gyrotron with external reflection in mode of several longitudinal modes

International Nuclear Information System (INIS)

Rozental', R.M.; Ginzburg, N.S.; Zajtsev, N.I.; Ilyakov, E.V.; Kulagin, I.S.

2006-01-01

One studies possibility to control the spectrum of multiparticle generation in a gyrotron due to application of external reflections. It is shown that in self-modulation regimes of generation the radiation spectrum lines may be close to the resonance frequencies throughout electrodynamic system covering a part of output waveguide restricted by a reflector. Under the mentioned conditions variation of distance between mode frequencies and, respectively, period of self-modulation may be reached due to varying of position of the reflector. The theory deductions are supported by the results of experimental investigation into 30 GHz region relativistic gyrotron with external reflections [ru

Stochastic Gabor reflectivity and acoustic impedance inversion

Science.gov (United States)

Hariri Naghadeh, Diako; Morley, Christopher Keith; Ferguson, Angus John

2018-02-01

To delineate subsurface lithology to estimate petrophysical properties of a reservoir, it is possible to use acoustic impedance (AI) which is the result of seismic inversion. To change amplitude to AI, removal of wavelet effects from the seismic signal in order to get a reflection series, and subsequently transforming those reflections to AI, is vital. To carry out seismic inversion correctly it is important to not assume that the seismic signal is stationary. However, all stationary deconvolution methods are designed following that assumption. To increase temporal resolution and interpretation ability, amplitude compensation and phase correction are inevitable. Those are pitfalls of stationary reflectivity inversion. Although stationary reflectivity inversion methods are trying to estimate reflectivity series, because of incorrect assumptions their estimations will not be correct, but may be useful. Trying to convert those reflection series to AI, also merging with the low frequency initial model, can help us. The aim of this study was to apply non-stationary deconvolution to eliminate time variant wavelet effects from the signal and to convert the estimated reflection series to the absolute AI by getting bias from well logs. To carry out this aim, stochastic Gabor inversion in the time domain was used. The Gabor transform derived the signal’s time-frequency analysis and estimated wavelet properties from different windows. Dealing with different time windows gave an ability to create a time-variant kernel matrix, which was used to remove matrix effects from seismic data. The result was a reflection series that does not follow the stationary assumption. The subsequent step was to convert those reflections to AI using well information. Synthetic and real data sets were used to show the ability of the introduced method. The results highlight that the time cost to get seismic inversion is negligible related to general Gabor inversion in the frequency domain. Also

Feasibility study for airborne fluorescence/reflectivity lidar bathymetry

Science.gov (United States)

Steinvall, Ove; Kautsky, Hans; Tulldahl, Michael; Wollner, Erika

2012-06-01

There is a demand from the authorities to have good maps of the coastal environment for their exploitation and preservation of the coastal areas. The goal for environmental mapping and monitoring is to differentiate between vegetation and non-vegetated bottoms and, if possible, to differentiate between species. Airborne lidar bathymetry is an interesting method for mapping shallow underwater habitats. In general, the maximum depth range for airborne laser exceeds the possible depth range for passive sensors. Today, operational lidar systems are able to capture the bottom (or vegetation) topography as well as estimations of the bottom reflectivity using e.g. reflected bottom pulse power. In this paper we study the possibilities and advantages for environmental mapping, if laser sensing would be further developed from single wavelength depth sounding systems to include multiple emission wavelengths and fluorescence receiver channels. Our results show that an airborne fluorescence lidar has several interesting features which might be useful in mapping underwater habitats. An example is the laser induced fluorescence giving rise to the emission spectrum which could be used for classification together with the elastic lidar signal. In the first part of our study, vegetation and substrate samples were collected and their spectral reflectance and fluorescence were subsequently measured in laboratory. A laser wavelength of 532 nm was used for excitation of the samples. The choice of 532 nm as excitation wavelength is motivated by the fact that this wavelength is commonly used in bathymetric laser scanners and that the excitation wavelengths are limited to the visual region as e.g. ultraviolet radiation is highly attenuated in water. The second part of our work consisted of theoretical performance calculations for a potential real system, and comparison of separability between species and substrate signatures using selected wavelength regions for fluorescence sensing.

Acoustic reflection log in transversely isotropic formations

Science.gov (United States)

Ronquillo Jarillo, G.; Markova, I.; Markov, M.

2018-01-01

We have calculated the waveforms of sonic reflection logging for a fluid-filled borehole located in a transversely isotropic rock. Calculations have been performed for an acoustic impulse source with the characteristic frequency of tens of kilohertz that is considerably less than the frequencies of acoustic borehole imaging tools. It is assumed that the borehole axis coincides with the axis of symmetry of the transversely isotropic rock. It was shown that the reflected wave was excited most efficiently at resonant frequencies. These frequencies are close to the frequencies of oscillations of a fluid column located in an absolutely rigid hollow cylinder. We have shown that the acoustic reverberation is controlled by the acoustic impedance of the rock Z = Vphρs for fixed parameters of the borehole fluid, where Vph is the velocity of horizontally propagating P-wave; ρs is the rock density. The methods of waveform processing to determine the parameters characterizing the reflected wave have been discussed.

An exploratory study of close supplier-manufacturer relationships

OpenAIRE

Goffin, Keith; Lemke, Fred; Szwejczewski, Marek

2006-01-01

Close relationships with selected suppliers can enable manufacturers to reduce costs, improve quality and enhance new product development. Although the advantages of close co-operation are widely acknowledged in the literature, the specific attributes of such relationships are not well understood. To address this gap, 39 managers responsible for purchasing were interviewed using a technique from psychology, which is particularly effective at uncovering the characteristics of...

Magnetoplasma reflectivity studies on Cd3As2

NARCIS (Netherlands)

Schleijpen, H.M.A.; Ortenberg, von M.; Gelten, M.J.; Blom, F.A.P.

1984-01-01

Magnetoplasma reflectivity measurements were performed on Cd3As2 in order to obtain more experimental details about the structure of the plasma reflectivity edge. The experimental results can be explained by assuming the existence of a surface layer with a carrier concentration-gradient which is

Ground magnetic studies along a regional seismic-reflection profile across Bare Mountain, Crater Flat and Yucca Mountain, Nevada

International Nuclear Information System (INIS)

Langenheim, V.E.; Ponce, D.A.

1995-01-01

Ground magnetic data were collected along a 26-km-long regional seismic-reflection profile in southwest Nevada that starts in the Amargosa Desert, crosses Bare Mountain, Crater Flat and Yucca Mountain, and ends in Midway Valley. Parallel ground magnetic profiles were also collected about 100 m to either side of the western half of the seismic-reflection line. The magnetic data indicate that the eastern half of Crater Flat is characterized by closely-spaced faulting (1--2 km) in contrast to the western half of Crater Flat. Modeling of the data indicates that the Topopah Spring Tuff is offset about 250 m on the Solitario Canyon fault and about 50 m on the Ghost Dance fault. These estimates of fault offset are consistent with seismic-reflection data and geologic mapping. A broad magnetic high of about 500--600 nT is centered over Crater Flat. Modeling of the magnetic data indicates that the source of this high is not thickening and doming of the Bullfrog Tuff, but more likely lies below the Bullfrog Tuff. Possible source lithologies for this magnetic high include altered argillite of the Eleana Formation, Cretaceous or Tertiary intrusions, and mafic sills

Teaching through mobile technology : a reflection from high school studies in South Africa

OpenAIRE

Jantjies, Mmaki; Joy, Mike

2017-01-01

The use of mobile technology to support teaching and learning in schools, has extended technology learning tools in schools across different socio economic divides. There have been various studies throughout the world which reflect the improvement of such technology in schools. In this chapter we reflect on a series of studies conducted in developing countries with focus on Jantjies and Joy (2012,2013,2014,2015) studies. The studies were conducted in schools with the objective of providing te...

Spacing and enclosure assembly for a reflecting thermal isolation panel

International Nuclear Information System (INIS)

Murdock, B.R.

1979-01-01

This invention concerns the thermal insulation assemblies and in particular a metallic assembly of stays and enclosures for a reflecting type panel used for insulation in nuclear reactors. Great flexibility is achieved by a corrugated strip placed edgewise around all the first reflecting insulating sheet. A second reflecting insulating sheet is then superposed on this corrugated strip which acts as a thickness spacer along the periphery of both sheets and also hermetically closes the intermediate space. The corrugations of the edge strip allow both sheets to be curved lengthwise or crosswise without causing their spacing to vary. These corrugations simply open like the pleats of an accordeon or a fan to fit the curve of the greatest radius [fr

Peer group reflection helps clinical teachers to critically reflect on their teaching.

Science.gov (United States)

Boerboom, Tobias B B; Jaarsma, Debbie; Dolmans, Diana H J M; Scherpbier, Albert J J A; Mastenbroek, Nicole J J M; Van Beukelen, Peter

2011-01-01

Student evaluations can help clinical teachers to reflect on their teaching skills and find ways to improve their teaching. Studies have shown that the mere presentation of student evaluations is not a sufficient incentive for teachers to critically reflect on their teaching. We evaluated and compared the effectiveness of two feedback facilitation strategies that were identical except for a peer reflection meeting. In this study, 54 clinical teachers were randomly assigned to two feedback strategies. In one strategy, a peer reflection was added as an additional step. All teachers completed a questionnaire evaluating the strategy that they had experienced. We analysed the reflection reports and the evaluation questionnaire. Both strategies stimulated teachers to reflect on feedback and formulate alternative actions for their teaching practice. The teachers who had participated in the peer reflection meeting showed deeper critical reflection and more concrete plans to change their teaching. All feedback strategies were considered effective by the majority of the teachers. Strategies with student feedback and self-assessment stimulated reflection on teaching and helped clinical teachers to formulate plans for improvement. A peer reflection meeting seemed to enhance reflection quality. Further research should establish whether it can have lasting effects on teaching quality.

Full-field transmission-type angle-deviation optical microscope with reflectivity-height transformation.

Science.gov (United States)

Chiu, Ming-Hung; Tan, Chen-Tai; Tsai, Ming-Hung; Yang, Ya-Hsin

2015-10-01

This full-field transmission-type three-dimensional (3D) optical microscope is constructed based on the angle deviation method (ADM) and the algorithm of reflectivity-height transformation (RHT). The surface height is proportional to the deviation angle of light passing through the object. The angle deviation and surface height can be measured based on the reflectivity closed to the critical angle using a parallelogram prism and two CCDs.

Temperature-reflection I

DEFF Research Database (Denmark)

McGady, David A.

2017-01-01

-temperature path integrals for quantum field theories (QFTs) should be T-reflection invariant. Because multi-particle partition functions are equal to Euclidean path integrals for QFTs, we expect them to be T-reflection invariant. Single-particle partition functions though are often not invariant under T......In this paper, we revisit the claim that many partition functions are invariant under reflecting temperatures to negative values (T-reflection). The goal of this paper is to demarcate which partition functions should be invariant under T-reflection, and why. Our main claim is that finite...... that T-reflection is unrelated to time-reversal. Finally, we study the interplay between T-reflection and perturbation theory in the anharmonic harmonic oscillator in quantum mechanics and in Yang-Mills in four-dimensions. This is the first in a series of papers on temperature-reflections....

Understanding the Development of a Hybrid Practice of Inquiry-Based Science Instruction and Language Development: A Case Study of One Teacher's Journey Through Reflections on Classroom Practice

Science.gov (United States)

Capitelli, Sarah; Hooper, Paula; Rankin, Lynn; Austin, Marilyn; Caven, Gennifer

2016-04-01

This qualitative case study looks closely at an elementary teacher who participated in professional development experiences that helped her develop a hybrid practice of using inquiry-based science to teach both science content and English language development (ELD) to her students, many of whom are English language learners (ELLs). This case study examines the teacher's reflections on her teaching and her students' learning as she engaged her students in science learning and supported their developing language skills. It explicates the professional learning experiences that supported the development of this hybrid practice. Closely examining the pedagogical practice and reflections of a teacher who is developing an inquiry-based approach to both science learning and language development can provide insights into how teachers come to integrate their professional development experiences with their classroom expertise in order to create a hybrid inquiry-based science ELD practice. This qualitative case study contributes to the emerging scholarship on the development of teacher practice of inquiry-based science instruction as a vehicle for both science instruction and ELD for ELLs. This study demonstrates how an effective teaching practice that supports both the science and language learning of students can develop from ongoing professional learning experiences that are grounded in current perspectives about language development and that immerse teachers in an inquiry-based approach to learning and instruction. Additionally, this case study also underscores the important role that professional learning opportunities can play in supporting teachers in developing a deeper understanding of the affordances that inquiry-based science can provide for language development.

Reflection ciphers

DEFF Research Database (Denmark)

Boura, Christina; Canteaut, Anne; Knudsen, Lars Ramkilde

2017-01-01

study the necessary properties for this coupling permutation. Special care has to be taken of some related-key distinguishers since, in the context of reflection ciphers, they may provide attacks in the single-key setting.We then derive some criteria for constructing secure reflection ciphers...

Effects of Space Weathering on Reflectance Spectra of Ureilites: First Studies

Science.gov (United States)

Goodrich, C. A.; Gillis-Davis, J.; Cloutis, E.; Applin, D.; Takir, D.; Hibbitts, C.; Christoffersen, R.; Fries, M.; Klima, R.; Decker, S.

2018-01-01

Ureilites are differentiated meteorites (ultramafic rocks interpreted to be mantle residues) that contain as much carbon as the most carbon-rich carbonaceous chondrites (CCs). Reflectance spectra of ureilites are similar to those of some CCs. Hence, ureilitic asteroids may accidentally be categorized as primitive because their spectra could resemble those of C-complex asteroids, which are thought to be CC-like. We began spectral studies of progressively laser-weathered ureilites with the goals of predicting UV-VIS-IR spectra of ureilitic asteroids, and identifying features that could distinguish differentiated from primitive dark asteroids. Space weathering has not previously been studied for ureilites, and, based on space weathering studies of CCs and other C-rich materials, it could significantly alter their reflectance spectra.

THE REFLECTION EFFECT IN INTERACTING BINARIES OR IN PLANET-STAR SYSTEMS

International Nuclear Information System (INIS)

Budaj, J.

2011-01-01

There are many similarities between interacting binary stars and stars with a close-in giant extrasolar planet. The reflection effect is a well-known example. Although the generally accepted treatment of this effect in interacting binaries is successful in fitting light curves of eclipsing binaries, it is not very suitable for studying cold objects irradiated by hot objects or extrasolar planets. The aim of this paper is to develop a model of the reflection effect which could be easily incorporated into the present codes for modeling of interacting binaries so that these can be used to study the aforementioned objects. Our model of the reflection effect takes into account the reflection (scattering), heating, and heat redistribution over the surface of the irradiated object. The shape of the object is described by the non-spherical Roche potential expected for close objects. Limb and gravity darkening are included in the calculations of the light output from the system. The model also accounts for the orbital revolution and rotation of the exoplanet with appropriate Doppler shifts for the scattered and thermal radiation. Subsequently, light curves and/or spectra of several exoplanets have been modeled and the effects of the heat redistribution, limb darkening/brightening, (non-)gray albedo, and non-spherical shape have been studied. Recent observations of planet-to-star flux ratio of HD189733b, WASP12b, and WASP-19b at various phases were reproduced with very good accuracy. It was found that HD189733b has a low Bond albedo and intense heat redistribution, while WASP-19b has a low Bond albedo and low heat redistribution. The exact Roche geometries and temperature distributions over the surface of all 78 transiting extrasolar planets have been determined. Departures from the spherical shape may vary considerably but departures of about 1% in the radius are common within the sample. In some cases, these departures can reach 8%, 12%, or 14%, for WASP-33b, WASP-19b, and

Vertical seismic profiling and integration with reflection seismic studies at Laxemar, 2000

International Nuclear Information System (INIS)

Juhlin, C.; Bergman, B.; Cosma, C.; Keskinen, J.; Enescu, N.

2002-02-01

Vertical seismic profile (VSP) data were acquired in October 2000 in the 1700 m deep KLX02 borehole, near Laxemar in southeastern Sweden. The objectives of the VSP were to image reflectors in the borehole for correlation with surface seismic and borehole data, study the signal penetration of explosive versus mechanical sources and determine the seismic velocity as a function of depth. Five principal source points were used, one located close to the KLX02 wellhead and 4 others that were offset by about 200 m to 400 m. An explosive source was only used at the wellhead and consisted of 15 grams of dynamite in 90 cm deep shot holes in bedrock. A swept impact seismic source (SIST) was also used at the wellhead, as well as at the other four offset source points. The primary SIST source consisted of a computer controlled mechanical hammer mounted on a tractor. By activating the hammer over a 15 second sweep length, the total energy transferred to the ground is on the same order as that produced by the dynamite. The recorded data are then processed to generate seismic records that are equivalent to a single impact source. A smaller hand held SIST source was also tested at the wellhead. Tests of both the tractor mounted source and dynamite were made at a location offset somewhat from the wellhead at a site containing loose sediments at the surface. Full waveform sonic, resistivity and gamma logs were also acquired in conjunction the VSP survey. A comparison between the explosive and large SIST source shows that comparable energy levels are produced by the two methods. The SIST source appears to be more stable in terms of the energy level, although the frequency content of data are somewhat lower. However, its most significant advantage is the low cost of preparation of the source points and the speed of the acquisition. Numerous reflections are observed on the VSP, as is the case on the surface seismic, implying a complex structure in the vicinity of the KLX02 borehole

Vertical seismic profiling and integration with reflection seismic studies at Laxemar, 2000

Energy Technology Data Exchange (ETDEWEB)

Juhlin, C.; Bergman, B. [Uppsala Univ. (Sweden); Cosma, C.; Keskinen, J.; Enescu, N. [Vibrometric Oy, Helsinki (Finland)

2002-02-01

Vertical seismic profile (VSP) data were acquired in October 2000 in the 1700 m deep KLX02 borehole, near Laxemar in southeastern Sweden. The objectives of the VSP were to image reflectors in the borehole for correlation with surface seismic and borehole data, study the signal penetration of explosive versus mechanical sources and determine the seismic velocity as a function of depth. Five principal source points were used, one located close to the KLX02 wellhead and 4 others that were offset by about 200 m to 400 m. An explosive source was only used at the wellhead and consisted of 15 grams of dynamite in 90 cm deep shot holes in bedrock. A swept impact seismic source (SIST) was also used at the wellhead, as well as at the other four offset source points. The primary SIST source consisted of a computer controlled mechanical hammer mounted on a tractor. By activating the hammer over a 15 second sweep length, the total energy transferred to the ground is on the same order as that produced by the dynamite. The recorded data are then processed to generate seismic records that are equivalent to a single impact source. A smaller hand held SIST source was also tested at the wellhead. Tests of both the tractor mounted source and dynamite were made at a location offset somewhat from the wellhead at a site containing loose sediments at the surface. Full waveform sonic, resistivity and gamma logs were also acquired in conjunction the VSP survey. A comparison between the explosive and large SIST source shows that comparable energy levels are produced by the two methods. The SIST source appears to be more stable in terms of the energy level, although the frequency content of data are somewhat lower. However, its most significant advantage is the low cost of preparation of the source points and the speed of the acquisition. Numerous reflections are observed on the VSP, as is the case on the surface seismic, implying a complex structure in the vicinity of the KLX02 borehole

Magnetic anisotropy and magnetoresistance in Co-based multilayers: a polarised neutron reflectivity study

International Nuclear Information System (INIS)

Yusuf, S.M.

2000-01-01

We have studied giant magnetoresistance (GMR) and anisotropic magnetoresistance (AMR) effects by carrying out magnetization, magnetoresistance and polarized neutron reflectivity measurements on epitaxial Co/Re multilayers. Polarized neutron reflectivity study with polarization analysis gives a direct way to sense the direction of sublattice magnetization and coupling between magnetic layers. The evolution of magnetic structure as a function of the strength and direction of the applied magnetic field has been studied. The AMR effect observed in magnetoresistance study has been explained in the light of observed magnetic structure. (author)

Comparative photoluminescence study of close-packed and colloidal InP/ZnS quantum dots

Science.gov (United States)

Thuy, Ung Thi Dieu; Thuy, Pham Thi; Liem, Nguyen Quang; Li, Liang; Reiss, Peter

2010-02-01

This letter reports on the comparative photoluminescence study of InP/ZnS quantum dots in the close-packed solid state and in colloidal solution. The steady-state photoluminescence spectrum of the close-packed InP/ZnS quantum dots peaks at a longer wavelength than that of the colloidal ones. Time-resolved photoluminescence shows that the close-packed quantum dots possess a shorter luminescence decay time and strongly increased spectral shift with the time delayed from the excitation moment in comparison with the colloidal ones. The observed behavior is discussed on the basis of energy transfer enabled by the short interparticle distance between the close-packed quantum dots.

SA72. Neural Correlates of Self-Reflection in Schizophrenia: A Functional Magnetic Resonance Imaging Study

Science.gov (United States)

Hiremath, Chaitra; Dey, Avyarthana

2017-01-01

Abstract Background: Self-reflection is the process of conscious evaluation of one’s traits, abilities, and attitudes. Deficient self-reflective processes might underlie lack of insight into schizophrenia. The limited research literature on the neural correlates of self-reflection in schizophrenia is inconclusive. In this study, we investigated the neural correlates of self-reflection in schizophrenia patients attending a tertiary care hospital in India. Methods: Nineteen male schizophrenia patients (mean age = 32.68 ± 7.11, mean years of education =15.21 ± 1.93) and 19 male healthy controls (mean age = 26.96 ± 4.67, mean years of education = 18.11 ± 3.13) participated in the study. Participants performed a previously validated self-reflection task while undergoing functional magnetic resonance imaging (fMRI; 3-Tesla). The task comprised of 144 words subdivided into 4 domains: Self-reflection, Other-reflection, Affect labeling, and Perceptual. The task was presented as 3 runs of 8 blocks each. The images were preprocessed and analyzed using SPM-12. After preprocessing, contrasts comparing Self-reflection with the other domains were modeled at the individual subject level. In second-level analysis, the first-level contrasts were entered into a 2-sample t test to compare patient and healthy control groups. The results were thresholded at P Self-reflection > Other-reflection contrast, schizophrenia patients demonstrated greater activation of right and left superior parietal lobules (BA 5 and 7), right inferior parietal lobule (BA 39), left parahippocampal gyrus (BA 36), and left premotor cortex (BA 6). For the Self-reflection > Affect labeling contrast, patients showed greater activation of precuneus (BA 7) and right inferior occipital gyrus (BA 19), and lesser activation of left inferior frontal gyrus (BA 45 and 47). And for the Self-reflection > Perceptual contrast, patients showed greater activation of left middle frontal gyrus (BA 10

Designing a Reflective Teacher Education Course and Its Contribution to ELT Teachers' Reflectivity

Science.gov (United States)

Tajik, Leila; Pakzad, Kazem

2016-01-01

Researchers in the present study planned a reflective teacher education course and documented the contribution of such a course to improving teachers' reflectivity. Five English teachers took part in the reflective teacher education course designed by the researchers. To record how the course could help improve reflective teaching, researchers…

A Tissue Propagation Model for Validating Close-Proximity Biomedical Radiometer Measurements

Science.gov (United States)

Bonds, Q.; Herzig, P.; Weller, T.

2016-01-01

The propagation of thermally-generated electromagnetic emissions through stratified human tissue is studied herein using a non-coherent mathematical model. The model is developed to complement subsurface body temperature measurements performed using a close proximity microwave radiometer. The model takes into account losses and reflections as thermal emissions propagate through the body, before being emitted at the skin surface. The derivation is presented in four stages and applied to the human core phantom, a physical representation of a stomach volume of skin, muscle, and blood-fatty tissue. A drop in core body temperature is simulated via the human core phantom and the response of the propagation model is correlated to the radiometric measurement. The results are comparable, with differences on the order of 1.5 - 3%. Hence the plausibility of core body temperature extraction via close proximity radiometry is demonstrated, given that the electromagnetic characteristics of the stratified tissue layers are known.

Evaluation of retro-reflective coating performance by reflectance and perceived relative brightness measurements

International Nuclear Information System (INIS)

Luse, Kaiva; Pausus, Anete; Karitans, Varis; Ozolins, Maris; Tukisa, Madara

2011-01-01

Retro-reflective properties of six types and five different colors or retro-reflective materials were discussed in this paper. Reflectance optical indicatrix of samples was determined and compared to obtained psychophyisical data of perceived brightness of human observer. Microscopic structure of the retro-reflective active regions of RR's was studied. Statistically significant differences in reflectivity and brightness of various types and colors of RR's were found.

Measuring Effects of Reflection on Learning – A Physiological Study

NARCIS (Netherlands)

Qi, Wen; Verpoorten, Dominique; Westera, Wim

2014-01-01

As an economical and feasible intervention, reflection demands learners using critical thinking to examine presented information, questioning its validity, and drawing conclusions based on the resulting ideas during a learning process. The aim of this study is to gain insight into the effects

Developing Multilingual Pedagogies and Research through Language Study and Reflection

Science.gov (United States)

Catalano, Theresa; Shende, Madhur; Suh, Emily K.

2018-01-01

Globalisation and increased transnational migration underscore the need for educational responses to multilingualism and multilingual discourses. One way to heighten awareness of multilingual pedagogies (while simultaneously providing data for multilingual research) is the use of reflective language study and journaling by language…

Cultivating Reflective Practitioners in Technology Preparation: Constructing TPACK through Reflection

Directory of Open Access Journals (Sweden)

Liangyue Lu

2013-12-01

Full Text Available Teaching is a complex profession, which is further complicated by the integration of technology into classrooms. Reflection can help teachers unpack the complexity in their practice. Reflection can be an effective instructional strategy in helping preservice teachers develop technological pedagogical content knowledge (TPACK, the complex and dynamic knowledge necessary for effective technology integration into instruction. In this study, reflective activities were integrated into a Learning By Design (LBD environment, which was created to help preservice teachers develop TPACK. This paper investigated the participants’ TPACK development and examined how reflection helped them construct TPACK. Through content analysis of the participants’ reflective journals, the researcher found that the preservice teachers developed initial TPACK awareness. However, their reflection in technology knowledge and the content aspects of TPACK were limited and superficial. Interviews with the participants showed reflection helped the preservice teachers remember what they learned by describing and elaborating on their in-class experiences, pushed them to think about how to apply what they learned in their future classrooms, and helped them become more reflective and open-minded about using technology in classrooms. Finally, the researcher discussed this study’s implications for teacher educators and researchers.

First occurrence of close-to-ideal Kirkiite at Vulcano (Aeolian Islands, Italy)

DEFF Research Database (Denmark)

Pinto, Daniela; Balic-Zunic, Tonci; Garavelli, anna

2006-01-01

Samples of kirkiite from the high temperature fumaroles of La Fossa crater of Vulcano (Aeolian islands, Italy) were chemically and structurally investigated in this work. Associated minerals are vurroite, bismuthinite, galenobismutite, cannizzarite, lillianite, heyrovsk ite, galena, and other less...... of the close-to-ideal kirkiite from Vulcano has been compared with the structure of the type specimen. The comparison reveals a variation in As-Bi substitution, with samples from Vulcano probably being close to the maximum possible Bi and the minimum As content for this structure type. This is reflected...

Evaluation of retro-reflective coating performance by reflectance and perceived relative brightness measurements

Energy Technology Data Exchange (ETDEWEB)

Luse, Kaiva; Pausus, Anete; Karitans, Varis; Ozolins, Maris; Tukisa, Madara, E-mail: kaiva.luse@gmail.com [University of Latvia, Optometry and Vision Science Department, Kengaraga street 8, Riga LV-1063 (Latvia)

2011-06-23

Retro-reflective properties of six types and five different colors or retro-reflective materials were discussed in this paper. Reflectance optical indicatrix of samples was determined and compared to obtained psychophyisical data of perceived brightness of human observer. Microscopic structure of the retro-reflective active regions of RR's was studied. Statistically significant differences in reflectivity and brightness of various types and colors of RR's were found.

Glimpses into the transition world: New graduate nurses' written reflections.

Science.gov (United States)

Walton, Jo Ann; Lindsay, Natalie; Hales, Caz; Rook, Helen

2018-01-01

This study was born out of our reflections as educators responsible for helping new graduate nurses transition into their first year of professional practice through a formal education programme. Finding ourselves wondering about many of the questions the students raised with us, we set about looking more closely at what could be gleaned from the students' experience, captured in their written work over the course of a year. To identify the challenges and learning experiences revealed in reflective assignments written by new graduate nurses undertaking a postgraduate course as part of their transition to registered nurse practice. Data consisted of the written work of two cohorts of students who had completed a postgraduate university course as part of their transition to new graduate practice in New Zealand. Fifty four reflective essays completed by twenty seven participating students were collected and their contents analysed thematically. Five key themes were identified. The students' reflections noted individual attributes - personal and professional strengths and weaknesses; professional behaviour - actions such as engaging help and support, advocating for patients' needs and safety and putting their own feelings aside; situational challenges such as communication difficulties, both systemic and interpersonal, and the pressure of competing demands. Students also identified rewards - results they experienced such as achieving the nursing outcomes they desired, and commented on reflection as a useful tool. The findings shed light on the experiences of new graduates, and how they fare through this critical phase of career development. Challenges relating to the emotional labour of nursing work are particularly evident. In addition the reflective essay is shown to be a powerful tool for assisting both new graduate nurses and their lecturers to reflect on the learning opportunities inherent in current clinical practice environments. Copyright © 2017 Elsevier Ltd

Gen-2 Hand-Held Optical Imager towards Cancer Imaging: Reflectance and Transillumination Phantom Studies

Directory of Open Access Journals (Sweden)

Anuradha Godavarty

2012-02-01

Full Text Available Hand-held near-infrared (NIR optical imagers are developed by various researchers towards non-invasive clinical breast imaging. Unlike these existing imagers that can perform only reflectance imaging, a generation-2 (Gen-2 hand-held optical imager has been recently developed to perform both reflectance and transillumination imaging. The unique forked design of the hand-held probe head(s allows for reflectance imaging (as in ultrasound and transillumination or compressed imaging (as in X-ray mammography. Phantom studies were performed to demonstrate two-dimensional (2D target detection via reflectance and transillumination imaging at various target depths (1–5 cm deep and using simultaneous multiple point illumination approach. It was observed that 0.45 cc targets were detected up to 5 cm deep during transillumination, but limited to 2.5 cm deep during reflectance imaging. Additionally, implementing appropriate data post-processing techniques along with a polynomial fitting approach, to plot 2D surface contours of the detected signal, yields distinct target detectability and localization. The ability of the gen-2 imager to perform both reflectance and transillumination imaging allows its direct comparison to ultrasound and X-ray mammography results, respectively, in future clinical breast imaging studies.

Dynamic polarization by coulomb excitation in the closed formalism for heavy ion scattering

International Nuclear Information System (INIS)

Frahn, W.E.; Hill, T.F.

1978-01-01

We present a closed-form treatment of the effects of dynamic polarization by Coulomb excitation on the elastic scattering of deformed heavy ions. We assume that this interaction can be represented by an absorptive polarization potential. The relatively long range of this potential entails a relatively slow variation of the associated reflection function in l-space. This feature leads to a simple generalization of the closed formula derived previously for the elastic scattering amplitude of spherical heavy nuclei. We use both the polarization potential of Love et al. and the recent improved potential of Baltz et al. to derive explicit expressions for the associated reflection functions in a Coulomb-distorted eikonal approximation. As an example we analyze the elastic scattering of 90-MeV 18 O ions by 184 W and show that both results give a quantitative description of the data. (orig.) [de

Study and field verification of the effects of removing closing resistors from 500 kV circuit breakers

International Nuclear Information System (INIS)

Selin, D.A.; Agrawal, B.L.; Farmer, R.G.; Demcko, J.A.

1992-01-01

Closing resistors in EHV circuit breakers are frequently used to reduce switching transients on lines thus preventing flashovers during line energization. Maintenance and failures of such closing resistors can be costly and reduce transmission system reliability. For these reasons, APS conducted an investigation into the technical feasibility of operating its 500 kV without closing resistors. This paper describes study results of removing closing resistors from 500 kV breakers in a system which employs older technology silicon carbide type surge arresters. The paper also describes results of field tests of the expected flashover rates calculated in the study. These field tests involve repeatedly energizing a 258 mile 500 kV line using a breaker in which the closing resistors are disabled. Transient overvoltages captured during the tests are compared with predicted overvoltages. The study concludes that closing resistors may be removed from the subject system without unacceptable consequences

On the effect of a tangential discontinuity on ions specularly reflected at an oblique shock

International Nuclear Information System (INIS)

Burgess, D.

1989-01-01

In seeking to explain the events observed close to the Earth's bow shock known as hot, diamagnetic cavities (HDC), or active current sheets (ACS), attention has focused on the microphysics of the interaction of a magnetic field directional discontinuity and a collisionless, supercritical shock. Here the author investigates the case of a tangential discontinuity (TD) convecting into a shock at some arbitrary angle. As a first stage he adopted an approach in which test particles represent ions specularly reflected at the shock front. Widely different behavior is possible depending on the sense of ion gyration relative to the TD. Particles can be injected into the plane of the TD so that they travel upstream trapped close to the TD. This implies that ACS events, presumed to be the result of the interaction of the solar wind with a large density reflected component, are detached from the bow shock. For other geometries, ions interact with the TD but stay close to the shock, implying that ACS events are modifications of the shock. The TD can deprive a limited spatial region of a downstream reflected gyrating ion population (necessary for the quasi-perpendicular supercritical shock to be steady), and so he could anticipate where the shock will not be in equilibrium, and consequently where strong reflection may occur. The detailed behavior of the shock in such a situation must be investigated with self-consistent simulations

A three-microphone acoustic reflection technique using transmitted acoustic waves in the airway.

Science.gov (United States)

Fujimoto, Yuki; Huang, Jyongsu; Fukunaga, Toshiharu; Kato, Ryo; Higashino, Mari; Shinomiya, Shohei; Kitadate, Shoko; Takahara, Yutaka; Yamaya, Atsuyo; Saito, Masatoshi; Kobayashi, Makoto; Kojima, Koji; Oikawa, Taku; Nakagawa, Ken; Tsuchihara, Katsuma; Iguchi, Masaharu; Takahashi, Masakatsu; Mizuno, Shiro; Osanai, Kazuhiro; Toga, Hirohisa

2013-10-15

The acoustic reflection technique noninvasively measures airway cross-sectional area vs. distance functions and uses a wave tube with a constant cross-sectional area to separate incidental and reflected waves introduced into the mouth or nostril. The accuracy of estimated cross-sectional areas gets worse in the deeper distances due to the nature of marching algorithms, i.e., errors of the estimated areas in the closer distances accumulate to those in the further distances. Here we present a new technique of acoustic reflection from measuring transmitted acoustic waves in the airway with three microphones and without employing a wave tube. Using miniaturized microphones mounted on a catheter, we estimated reflection coefficients among the microphones and separated incidental and reflected waves. A model study showed that the estimated cross-sectional area vs. distance function was coincident with the conventional two-microphone method, and it did not change with altered cross-sectional areas at the microphone position, although the estimated cross-sectional areas are relative values to that at the microphone position. The pharyngeal cross-sectional areas including retropalatal and retroglossal regions and the closing site during sleep was visualized in patients with obstructive sleep apnea. The method can be applicable to larger or smaller bronchi to evaluate the airspace and function in these localized airways.

An editor's memoir: reflections and premonitions.

Science.gov (United States)

Kovacs, Arthur L

2013-12-01

The author served as the second Editor of this journal. In the article that follows, he reminisces about the state of the publication when he assumed responsibility for it and comments on the nature of the profession during the time of his incumbency. He reflects on the creative innovation and ferment in both the theories and tactics of psychotherapy unfolding during the 1970s and closes with statements of concern about developments within the field that are ominous and have come to the fore over the decades since he left office in 1983.

Postgraduate Education to Support Organisation Change: A Reflection on Reflection

Science.gov (United States)

Stewart, Jim; Keegan, Anne; Stevens, Pam

2008-01-01

Purpose: This paper aims to explore how teaching and assessing reflective learning skills can support postgraduate practitioners studying organisational change and explores the challenges for tutors in assessing these journals. Design/methodology/approach: Assessment criteria were developed from the literature on reflective practice and…

If These Walls Could Talk: Reflective Practice in Addiction Studies among Undergraduates in New Zealand

Science.gov (United States)

Shepherd, Robin

2010-01-01

This exploratory study examined reflective practice among a class of students studying a "communities and addictions" course as part of the undergraduate health science degree. Most reflective practice publications are focused on medical or teachers' training rather than undergraduates in general. This is surprising given that reflective…

Ultra-wideband high-efficiency reflective linear-to-circular polarization converter based on metasurface at terahertz frequencies.

Science.gov (United States)

Jiang, Yannan; Wang, Lei; Wang, Jiao; Akwuruoha, Charles Nwakanma; Cao, Weiping

2017-10-30

The polarization conversion of electromagnetic (EM) waves, especially linear-to-circular (LTC) polarization conversion, is of great significance in practical applications. In this study, we propose an ultra-wideband high-efficiency reflective LTC polarization converter based on a metasurface in the terahertz regime. It consists of periodic unit cells, each cell of which is formed by a double split resonant square ring, dielectric layer, and fully reflective gold mirror. In the frequency range of 0.60 - 1.41 THz, the magnitudes of the reflection coefficients reach approximately 0.7, and the phase difference between the two orthogonal electric field components of the reflected wave is close to 90° or -270°. The results indicate that the relative bandwidth reaches 80% and the efficiency is greater than 88%, thus, ultra-wideband high-efficiency LTC polarization conversion has been realized. Finally, the physical mechanism of the polarization conversion is revealed. This converter has potential applications in antenna design, EM measurement, and stealth technology.

Reflection: A Socratic approach.

Science.gov (United States)

Van Seggelen-Damen, Inge C M; Van Hezewijk, René; Helsdingen, Anne S; Wopereis, Iwan G J H

2017-12-01

Reflection is a fuzzy concept. In this article we reveal the paradoxes involved in studying the nature of reflection. Whereas some scholars emphasize its discursive nature, we go further and underline its resemblance to the self-biased dialogue Socrates had with the slave in Plato's Meno . The individual and internal nature of the reflection process creates difficulty for studying it validly and reliably. We focus on methodological issues and use Hans Linschoten's view of coupled systems to identify, analyze, and interpret empirical research on reflection. We argue that researchers and research participants can take on roles in several possible system couplings. Depending on who controls the manipulation of the stimulus, who controls the measuring instrument, who interprets the measurement and the response, different types of research questions can be answered. We conclude that reflection may be validly studied by combining different couplings of experimenter, manipulation, stimulus, participant, measurement, and response.

3D-Printed Broadband Dielectric Tube Terahertz Waveguide with Anti-Reflection Structure

Science.gov (United States)

Vogt, Dominik Walter; Leonhardt, Rainer

2016-11-01

We demonstrate broadband, low loss, and close-to-zero dispersion guidance of terahertz (THz) radiation in a dielectric tube with an anti-reflection structure (AR-tube waveguide) in the frequency range from 0.2 to 1.0 THz. The anti-reflection structure (ARS) consists of close-packed cones in a hexagonal lattice arranged on the outer surface of the tube cladding. The feature size of the ARS is in the order of the wavelength between 0.2 and 1.0 THz. The waveguides are fabricated with the versatile and cost efficient 3D-printing method. Terahertz time-domain spectroscopy (THz-TDS) measurements as well as 3D finite-difference time-domain simulations (FDTD) are performed to extensively characterize the AR-tube waveguides. Spectrograms, attenuation spectra, effective phase refractive indices, and the group-velocity dispersion parameters β 2 of the AR-tube waveguides are presented. Both the experimental and numerical results confirm the extended bandwidth and smaller group-velocity dispersion of the AR-tube waveguide compared to a low loss plain dielectric tube THz waveguide. The AR-tube waveguide prototypes show an attenuation spectrum close to the theoretical limit given by the infinite cladding tube waveguide.

PRELIMINARY STUDY ON RETRO-REFLECTIVE COATED PAPER BASED ON MICRO-GLASS BEADS

Institute of Scientific and Technical Information of China (English)

Yulong Wang; Chuanshan Zhao; Tao Zhang

2004-01-01

High-reflectivity micro-glass bead, as a kind of retro-reflective material, is widely used in reflective fabric or film and other reflective coatings. But it is rarely used in coated paper. The retro-reflective theory of micro-bead is described. Also the effect of size of micro-bead, dosage of binder and different color layers on reflective properties of coated paper are discussed in this article. The results show that its retro-reflective efficiency is good, equally to reflective fabric or film when the micro-glass bead is used in coated paper.

The Reflective Learning Continuum: Reflecting on Reflection

Science.gov (United States)

Peltier, James W.; Hay, Amanda; Drago, William

2005-01-01

The importance of reflection to marketing educators is increasingly recognized. However, there is a lack of empirical research that considers reflection within the context of both the marketing and general business education literature. This article describes the use of an instrument that can be used to measure four identified levels of a…

Ground-penetrating radar study of the Cena Bog, Latvia: linkage of reflections with peat moisture content

Directory of Open Access Journals (Sweden)

Karušs, J.

2015-12-01

Full Text Available Present work illustrates results of the ground-penetrating radar (GPR study of the Cena Bog, Latvia. Six sub-horizontal reflections that most probably correspond to boundaries between sediments with different electromagnetic properties were identified. One of the reflections corresponds to bog peat mineral bottom interface but the rest are linked to boundaries within the peat body. The radar profiles are incorporated with sediment cores and studies of peat moisture and ash content, and degree of decomposition. Most of the electromagnetic wave reflections are related to changes in peat moisture content. The obtained data show that peat moisture content changes of at least 3 % are required to cause GPR signal reflection. However, there exist reflections that do not correlate with peat moisture content. As a result, authors disagree with a dominant opinion that all reflections in bogs are solely due to changes in volumetric peat moisture content.

Resonant soft x-ray reflectivity of Me/B4C multilayers near the boron K edge

Energy Technology Data Exchange (ETDEWEB)

Ksenzov, Dmitriy; Schlemper, Christoph; Pietsch, Ullrich

2010-09-01

Energy dependence of the optical constants of boron carbide in the short period Ru/B4C and Mo/B4C multilayers (MLs) are evaluated from complete reflectivity scans across the boron K edge using the energy-resolved photon-in-photon-out method. Differences between the refractive indices of the B4Cmaterial inside and close to the surface are obtained from the peak profile of the first order ML Bragg peak and the reflection profile near the critical angle of total external reflection close to the surface. Where a Mo/B4C ML with narrow barrier layers appears as a homogeneous ML at all energies, a Ru/B4C ML exhibits another chemical nature of boron at the surface compared to the bulk. From evaluation of the critical angle of total external reflection in the energy range between 184 and 186 eV, we found an enriched concentration of metallic boron inside the Ru-rich layer at the surface, which is not visible in other energy ranges.

Reflective and collaborative skills enhances Ambulance nurses' competence - A study based on qualitative analysis of professional experiences.

Science.gov (United States)

Wihlborg, Jonas; Edgren, Gudrun; Johansson, Anders; Sivberg, Bengt

2017-05-01

The Swedish ambulance health care services are changing and developing, with the ambulance nurse playing a central role in the development of practice. The competence required by ambulance nurses in the profession remains undefined and provides a challenge. The need for a clear and updated description of ambulance nurses' competence, including the perspective of professional experiences, seems to be essential. The aim of this study was to elucidate ambulance nurses' professional experiences and to describe aspects affecting their competence. For data collection, the study used the Critical Incident Technique, interviewing 32 ambulance nurses. A qualitative content analysis was applied. This study elucidates essential parts of the development, usage and perceptions of the competence of ambulance nurses and how, in various ways, this is affected by professional experiences. The development of competence is strongly affected by the ability and possibility to reflect on practice on a professional and personal level, particularly in cooperation with colleagues. Experiences and communication skills are regarded as decisive in challenging clinical situations. The way ambulance nurses perceive their own competence is closely linked to patient outcome. The results of this study can be used in professional and curriculum development. Copyright © 2016 Elsevier Ltd. All rights reserved.

An experimental study on crib fires in a closed compartment

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Dhurandher Bhisham Kumar

2017-01-01

Full Text Available An experimental investigation on burning behavior of fire in closed compartments is presented. Fire experiments were performed in a closed compartment of interior dimensions 4 × 4 × 4 m (length × width × height with ply board cribs as fire source. The parameters including the gas temperature, mass loss rate, heat flux, flame temperature, and compartment pressure were measured during the experiments. Experimental results indicated that the providing sudden ventilation to the closed compartment had great influence on the behavior of fire. The mass loss rate of the burning crib increased by 150% due to sudden ventilation which results in the increase in heat release rate by 198 kW. From the perspective of total heat flux, compartment pressure, and gas temperatures closed compartment with sudden ventilation were more hazardous.

Principles of shape from specular reflection

KAUST Repository

Balzer, Jonathan

2010-12-01

The reconstruction of (partially) specular object by means of deflectometric methods is a challenging task. It has a long and fairly branched history within the metrology and machine vision communities. We are not aware of any scientific publication surveying the state of the art in a unifying manner and thus stimulating further research. This contribution is intended to close this gap, bringing together prominent ideas from both fields. In avoidance of unnecessary technicality, we lay out the basic theory, including all known forward models of the reflection process. The corresponding inverse problem is ill-posed, so that special emphasis is put on the question of regularization. We embed some novel results on the uniqueness problem and the effectiveness of regularization approaches. Also an overview of numerical methods related to Shape from Specular Reflection is given. For the sake of completeness, we share some thoughts on the construction of an actual measurement system and discuss a practical example. © 2010 Elsevier Ltd. All rights reserved.

A validation study of the psychometric properties of the Groningen Reflection Ability Scale

DEFF Research Database (Denmark)

Andersen, Nina Bjerre; O'Neill, Lotte; Gormsen, Lise Kirstine

2014-01-01

Background Reflection, the ability to examine critically one’s own learning and functioning, is considered important for ‘the good doctor’. The Groningen Reflection Ability Scale (GRAS) is an instrument measuring student reflection, which has not yet been validated beyond the original Dutch study....... The aim of this study was to adapt GRAS for use in a Danish setting and to investigate the psychometric properties of GRAS-DK. Methods We performed a cross-cultural adaptation of GRAS from Dutch to Danish. Next, we collected primary data online, performed a retest, analysed data descriptively, estimated...... measurement error, performed an exploratory and a confirmatory factor analysis to test the proposed three-factor structure. Results 361 (69%) of 523 invited students completed GRAS-DK. Their mean score was 88 (SD = 11.42; scale maximum 115). Scores were approximately normally distributed. Measurement error...

Social closeness and feedback modulate susceptibility to the framing effect

Science.gov (United States)

Sip, Kamila E.; Smith, David V.; Porcelli, Anthony J.; Kar, Kohitij; Delgado, Mauricio R.

2014-01-01

Although, we often seek social feedback from others to help us make decisions, little is known about how social feedback affects decisions under risk, particularly from a close peer. We conducted two experiments using an established framing task to probe how decision making is modulated by social feedback valence (positive, negative) and the level of closeness with feedback provider (friend, confederate). Participants faced mathematically equivalent decisions framed as either an opportunity to keep (gain frame) or lose (loss frame) part of an initial endowment. Periodically, participants were provided with positive (e.g., “Nice!”) or negative (e.g., “Lame!”) feedback about their choices. Such feedback was provided by either a confederate (Experiment 1), or a gender-matched close friend (Experiment 2). As expected, the framing effect was observed in both experiments. Critically, an individual’s susceptibility to the framing effect was modulated by the valence of the social feedback, but only when the feedback provider was a close friend. This effect was reflected in the activation patterns of ventromedial prefrontal cortex and posterior cingulate cortex, regions involved in complex decision making. Taken together, these results highlight social closeness as an important factor in understanding the impact of social feedback on neural mechanisms of decision making. PMID:25074501

Social closeness and feedback modulate susceptibility to the framing effect.

Science.gov (United States)

Sip, Kamila E; Smith, David V; Porcelli, Anthony J; Kar, Kohitij; Delgado, Mauricio R

2015-01-01

Although we often seek social feedback (SFB) from others to help us make decisions, little is known about how SFB affects decisions under risk, particularly from a close peer. We conducted two experiments using an established framing task to probe how decision-making is modulated by SFB valence (positive, negative) and the level of closeness with feedback provider (friend, confederate). Participants faced mathematically equivalent decisions framed as either an opportunity to keep (gain frame) or lose (loss frame) part of an initial endowment. Periodically, participants were provided with positive (e.g., "Nice!") or negative (e.g., "Lame!") feedback about their choices. Such feedback was provided by either a confederate (Experiment 1) or a gender-matched close friend (Experiment 2). As expected, the framing effect was observed in both experiments. Critically, an individual's susceptibility to the framing effect was modulated by the valence of the SFB, but only when the feedback provider was a close friend. This effect was reflected in the activation patterns of ventromedial prefrontal cortex and posterior cingulate cortex, regions involved in complex decision-making. Taken together, these results highlight social closeness as an important factor in understanding the impact of SFB on neural mechanisms of decision-making.

Self-Reflected Well-Being via a Smartphone App in Clinical Medical Students: Feasibility Study.

Science.gov (United States)

Berryman, Elizabeth K; Leonard, Daniel J; Gray, Andrew R; Pinnock, Ralph; Taylor, Barry

2018-03-07

Well-being in medical students has become an area of concern, with a number of studies reporting high rates of clinical depression, anxiety, burnout, and suicidal ideation in this population. The aim of this study was to increase awareness of well-being in medical students by using a smartphone app. The primary objective of this study was to determine the validity and feasibility of the Particip8 app for student self-reflected well-being data collection. Undergraduate medical students of the Dunedin School of Medicine were recruited into the study. They were asked to self-reflect daily on their well-being and to note what experiences they had encountered during that day. Qualitative data were also collected both before and after the study in the form of focus groups and "free-text" email surveys. All participants consented for the data collected to be anonymously reported to the medical faculty. A total of 29 participants (69%, 20/29 female; 31%, 9/29 male; aged 21-30 years) were enrolled, with overall median compliance of 71% at the study day level. The self-reflected well-being scores were associated with both positive and negative experiences described by the participants, with most negative experiences associated with around 20% lower well-being scores for that day; the largest effect being "receiving feedback that was not constructive or helpful," and the most positive experiences associated with around 20% higher scores for that day. The study of daily data collection via the Particip8 app was found to be feasible, and the self-reflected well-being scores showed validity against participant's reflections of experiences during that day. ©Elizabeth K Berryman, Daniel J Leonard, Andrew R Gray, Ralph Pinnock, Barry Taylor. Originally published in JMIR Medical Education (http://mededu.jmir.org), 07.03.2018.

Effect of Various Finishing Procedures on the Reflectivity (Shine) of Tooth Enamel - An In-vitro Study.

Science.gov (United States)

Patil, Harshal Ashok; Chitko, Shrikant Shrinivas; Kerudi, Veerendra Virupaxappa; Maheshwari, Amit Ratanlal; Patil, Neeraj Suresh; Tekale, Pawankumar Dnyandeo; Gore, Ketan Ashorao; Zope, Amit Ashok

2016-08-01

Reflectivity of an object is a good parameter for surface finish. As the patient evaluates finishing as a function of gloss/reflectivity/shine an attempt is made here to evaluate changes in surface finish with custom made reflectometer. The aim of the present study was to study the effect of various procedures during orthodontic treatment on the shine of enamel, using a custom made reflectometer. Sixty one extracted premolars were collected and each tooth was mounted on acrylic block. Reflectivity of the teeth was measured as compared to standard before any procedure. One tooth was kept as standard throughout the study. Sixty teeth were acid etched. Reflectivity was measured on custom made reflectometer and readings recorded. Same procedure was repeated after debonding. Then 60 samples were divided into three groups: Group 1 - Tungsten Carbide, Group 2 - Astropol, Group 3- Sof-Lex disc depending upon the finishing method after debonding and reflectivity was measured. The mean percentage of reflectivity after acid etching was 31.4%, debonding 45.5%, Tungsten carbide bur finishing (Group 1) was 58.3%, Astropol (Group 2) 72.8%, and Sof-Lex disc (Group 3) 84.4% as that to the standard. There was statistically very highly significant (p Group 2> Group 1. The primary goal was to restore the enamel to its original state after orthodontic treatment. The methods tested in this study could not restore the original enamel reflectivity.

The polarized neutron reflectivity and X-ray reflectivity studies of the magnetic profiles of epitaxial Ni80Fe20/Ru multilayers

International Nuclear Information System (INIS)

Su, H.-C.; Peir, J.-J.; Lee, C.-H.; Lin, M.-Z.; Wu, P.-T.; Huang, J.C.A.; Tun Zin

2005-01-01

The depth profiles of the epitaxial Ni 80 Fe 20 (1 1 1)/Ru(0 0 0 1) multilayers were studied by polarized neutron reflectivity and X-ray reflectivity. At the Ru thickness that the anti-ferromagnetic coupling was found, the magnetic moments between two Ni 80 Fe 20 interlayers show a biquadratic coupling effect with a double unit cell at low applied fields. A magnetic dead layer of about 0.3 nm was also found at the interface boundaries. The maximal polarization effect applied to the Ru layer is less than 0.03μ B

The Close Relationships of People with Intellectual Disabilities: A Qualitative Study

Science.gov (United States)

Sullivan, Faye; Bowden, Keith; McKenzie, Karen; Quayle, Ethel

2016-01-01

Background: Positive interpersonal relationships have been found to enhance an individual's quality of life. However, people with intellectual disabilities (PWID) often have restricted social networks, and little is known about their views on close social relationships. The study aimed to explore how this group perceives and experiences close…

Studying Abroad Inclusively: Reflections by College Students with and without Intellectual Disability

Science.gov (United States)

Prohn, Seb M.; Kelley, Kelly R.; Westling, David L.

2016-01-01

Postsecondary education programs have increased opportunities for students with and without intellectual disabilities to study abroad as inclusive classes. Using open-coding qualitative techniques, the authors examined an inclusive study abroad group's daily reflective journals during a study abroad trip to London and Dublin. Three shared…

Quantitative Estimation of Transmitted and Reflected Lamb Waves at Discontinuity

International Nuclear Information System (INIS)

Lim, Hyung Jin; Sohn, Hoon

2010-01-01

For the application of Lamb wave to structural health monitoring(SHM), understanding its physical characteristic and interaction between Lamb wave and defect of the host structure is an important issue. In this study, reflected, transmitted and mode converted Lamb waves at discontinuity of a plate structure were simulated and the amplitude ratios are calculated theoretically using Modal decomposition method. The predicted results were verified comparing with finite element method(FEM) and experimental results simulating attached PZTs. The result shows that the theoretical prediction is close to the FEM and the experimental verification. Moreover, quantitative estimation method was suggested using amplitude ratio of Lamb wave at discontinuity

Learning Opportunities in Case Studies for Becoming a Reflective Nurse Practitioner

NARCIS (Netherlands)

Dr. A.J. ter Maten - Speksnijder; A. Pool; J.N. Streumer; M.H.F. Grypdonck

2012-01-01

The transition from RN to nurse practitioner presents challenges. Because nurse practitioners require deeper critical decision-making abilities to provide safe and quality health care, the Master in Advanced Nursing Practice curriculum implemented reflective case studies to facilitate active and

The Influence of Repeated Teaching and Reflection on Preservice Teachers' Views of Inquiry and Nature of Science

Science.gov (United States)

Lotter, Christine; Singer, Jonathan; Godley, Jenice

2009-12-01

This study describes the influence of a secondary science methods program on secondary science preservice teachers’ views and enactment of nature of science and inquiry-based instructional practices. Built into the structure of this program were three cycles of practice teaching and reflection in which the preservice teachers focused on key pedagogical ideas in classroom settings with middle and high school students. The nine secondary preservice teachers improved both their understanding and enactment of inquiry and nature of science throughout the program period. This study provides evidence of the importance of incorporating multiple low-stakes practicum experiences that are closely tied to methods course goals that are highly scaffolded through both methods instructor and cooperating teacher support and tied to analytic self-reflection.

A DESCRIPTIVE STUDY OF CLOSED GLOBE INJURIES WITH HYPHAEMA

Directory of Open Access Journals (Sweden)

Susan Philip

2017-05-01

Full Text Available BACKGROUND Eye injuries still remain one of the most common causes of unilateral blindness worldwide. In addition to the physical and psychological trauma to the patient, the direct and indirect costs to the society are enormous. Blunt eye injuries commonly result in traumatic hyphaema and are not an infrequent cause of presentation to the emergency units of many eye clinics. Aims of this study were- 1. To study the cause, clinical presentation, complications and visual outcome of closed globe injury with hyphaema. 2. To know the association between mode of injuries and associated lesions and visual outcome. MATERIALS AND METHODS Study Design and Statistical Analysis- A descriptive case series study was conducted at Regional Institute of Ophthalmology, Thiruvananthapuram for a period of one year, from October 2010 to September 2011, in all patients coming to the institute with hyphaema due to closed globe injury and willing to participate in the study. Patients with pre-existing ocular diseases were excluded. Data were analysed using computer software, Statistical Package for Social Sciences (SPSS version 10. Data are expressed in its frequency and percentage. To elucidate the associations and comparisons between different parameters, Chi square ( 2 test was used as a nonparametric test. For all statistical evaluations, a two-tailed probability of value, 6/60 either maintained that vision or improved. Only 10% of the study population had corneal blood staining. Majority of those who had initial hyphaema <1/3 rd , had normal initial intraocular pressure. Of the total 36 patients who had initial hyphaema less than 1/3 rd , 29 (80.6% had normal intraocular pressure on presentation. Of the 36 patients with initial hyphaema <1/3 rd , 28 (77.8% had normal intraocular pressure at 3 rd day. Those who had lenticular and posterior segment injury had poor visual outcome. In our study, initially only 15% had vision better than 6/12, but at the end of 180

Detecting Close-In Extrasolar Giant Planets with the Kepler Photometer via Scattered Light

Science.gov (United States)

Jenkins, J. M.; Doyle, L. R.; Kepler Discovery Mission Team

2003-05-01

NASA's Kepler Mission will be launched in 2007 primarily to search for transiting Earth-sized planets in the habitable zones of solar-like stars. In addition, it will be poised to detect the reflected light component from close-in extrasolar giant planets (CEGPs) similar to 51 Peg b. Here we use the DIARAD/SOHO time series along with models for the reflected light signatures of CEGPs to evaluate Kepler's ability to detect such planets. We examine the detectability as a function of stellar brightness, stellar rotation period, planetary orbital inclination angle, and planetary orbital period, and then estimate the total number of CEGPs that Kepler will detect over its four year mission. The analysis shows that intrinsic stellar variability of solar-like stars is a major obstacle to detecting the reflected light from CEGPs. Monte Carlo trials are used to estimate the detection threshold required to limit the total number of expected false alarms to no more than one for a survey of 100,000 stellar light curves. Kepler will likely detect 100-760 51 Peg b-like planets by reflected light with orbital periods up to 7 days. LRD was supported by the Carl Sagan Chair at the Center for the Study of Life in the Universe, a division of the SETI Institute. JMJ received support from the Kepler Mission Photometer and Science Office at NASA Ames Research Center.

Challenging Narcissus, or Reflecting on Reflecting.

Science.gov (United States)

Achilles, C. M.

The concept of reflective practice and teaching people to be reflective practitioners is examined. The document begins with a look at professional knowledge according to three prominent professionals in the educational administration field: Schon, Schein, and Achilles. "Reflective" strategies that could be incorporated into courses and…

Parametric study of closed wet cooling tower thermal performance

Science.gov (United States)

Qasim, S. M.; Hayder, M. J.

2017-08-01

The present study involves experimental and theoretical analysis to evaluate the thermal performance of modified Closed Wet Cooling Tower (CWCT). The experimental study includes: design, manufacture and testing prototype of a modified counter flow forced draft CWCT. The modification based on addition packing to the conventional CWCT. A series of experiments was carried out at different operational parameters. In view of energy analysis, the thermal performance parameters of the tower are: cooling range, tower approach, cooling capacity, thermal efficiency, heat and mass transfer coefficients. The theoretical study included develops Artificial Neural Network (ANN) models to predicting various thermal performance parameters of the tower. Utilizing experimental data for training and testing, the models simulated by multi-layer back propagation algorithm for varying all operational parameters stated in experimental test.

Relationship between reflection ability and clinical performance: a cross-sectional and retrospective-longitudinal correlational cohort study in midwifery.

Science.gov (United States)

Embo, M; Driessen, E; Valcke, M; van der Vleuten, C P M

2015-01-01

increasingly, reflection is highlighted as integral to core practice competencies but empirical research into the relationship between reflection and performance in the clinical workplace is scarce. this study investigated the relationship between reflection ability and clinical performance. we designed a cross-sectional and a retrospective-longitudinal cohort study. Data from first, second and third year midwifery students were collected to study the variables 'clinical performance' and 'reflection ability'. Data were analysed with SPSS for Windows, Release 20.0. Descriptive statistics, Pearson׳s Product Moment Correlation Coefficients (r) and r² values were computed to investigate associations between the research variables. the results showed a moderate observed correlation between reflection ability and clinical performance scores. When adopting a cross-sectional perspective, all correlation values were significant (p0.6). The results based on the retrospective-longitudinal data set explained a moderate proportion of the variance after correction for attenuation. Finally, the results indicate that 'reflection ability' scores of earlier years are significant related with 'clinical performance' scores of subsequent years. These results suggest that (1) reflection ability is linked to clinical performance; (2) that written reflections are an important, but not the sole way to assess professional competence and that (3) reflection is a contributor to clinical performance improvement. the data showed a moderate but significant relationship between 'reflection ability' and 'clinical performance' scores in clinical practice of midwifery students. Reflection therefore seems an important component of professional competence. Copyright © 2014 Elsevier Ltd. All rights reserved.

Close binary stars

International Nuclear Information System (INIS)

Larsson-Leander, G.

1979-01-01

Studies of close binary stars are being persued more vigorously than ever, with about 3000 research papers and notes pertaining to the field being published during the triennium 1976-1978. Many major advances and spectacular discoveries were made, mostly due to increased observational efficiency and precision, especially in the X-ray, radio, and ultraviolet domains. Progress reports are presented in the following areas: observational techniques, methods of analyzing light curves, observational data, physical data, structure and models of close binaries, statistical investigations, and origin and evolution of close binaries. Reports from the Coordinates Programs Committee, the Committee for Extra-Terrestrial Observations and the Working Group on RS CVn binaries are included. (Auth./C.F.)

Measurement of the acoustic reflectivity of sirenia (Florida manatees) at 171 kHz.

Science.gov (United States)

Jaffe, Jules S; Simonet, Fernando; Roberts, Paul L D; Bowles, Ann E

2007-01-01

The Florida manatee (Trichechus manatus latirostris) is an endangered sirenian. At present, its adult population (approximately 2200) seems stable, but tenuous. Manatee-boat collisions are a significant proportion (approximately 25%) of mortalities. Here, the potential use of active sonar for detecting manatees by quantifying sonic reflectivity is explored. In order to estimate reflectivity two methods were used. One method measured live reflections from captive animals using a carefully calibrated acoustic and co-registered optical system. The other method consisted of the analysis of animal tissue in order to obtain estimates of the sound speed and density and to predict reflectivity. The impedance measurement predicts that for a lateral view, the tissue reflectivity is close to 0.13, with a critical grazing angle of 28 degrees. Data measured from live animals indicate that substantial reflections can be recorded, however in many instances observed "empirical target strengths" were less than an experimentally dependent -48-dB threshold. Conclusions favor the hypothesis that the animals reflect substantial amounts of sound; however, the reflections can often be specular, and therefore impractical for observation by a manatee detection sonar operating at 171 kHz.

Discharge lamp with reflective jacket

Science.gov (United States)

MacLennan, Donald A.; Turner, Brian P.; Kipling, Kent

2001-01-01

A discharge lamp includes an envelope, a fill which emits light when excited disposed in the envelope, a source of excitation power coupled to the fill to excite the fill and cause the fill to emit light, and a reflector disposed around the envelope and defining an opening, the reflector being configured to reflect some of the light emitted by the fill back into the fill while allowing some light to exit through the opening. The reflector may be made from a material having a similar thermal index of expansion as compared to the envelope and which is closely spaced to the envelope. The envelope material may be quartz and the reflector material may be either silica or alumina. The reflector may be formed as a jacket having a rigid structure which does not adhere to the envelope. The lamp may further include an optical clement spaced from the envelope and configured to reflect an unwanted component of light which exited the envelope back into the envelope through the opening in the reflector. Light which can be beneficially recaptured includes selected wavelength regions, a selected polarization, and selected angular components.

Experiences of self-practice/self-reflection in cognitive behavioural therapy: a meta-synthesis of qualitative studies.

Science.gov (United States)

Gale, Corinne; Schröder, Thomas

2014-12-01

Self-practice/self-reflection is a valuable training strategy which involves therapists applying therapeutic techniques to themselves, and reflecting on the process. To undertake a meta-synthesis of qualitative studies exploring therapists' experiences of self-practice/self-reflection in cognitive behavioural therapy (CBT). This would integrate, and interpret, the current literature in order to develop a new understanding, and contribute to the development of CBT training programmes. The meta-synthesis encompassed three distinct phases: undertaking a comprehensive and systematic literature search; critically appraising the papers; and synthesising the data using the meta-ethnographic method. The literature search identified 378 papers, ten met the criteria for inclusion. After critical appraisal, all were included in the synthesis. The synthesis identified 14 constructs, which fell into three broad categories: 'experience of self-practice/self-reflection'; 'outcomes of self-practice/self-reflection'; and 'implications for training'. This synthesis found that self-practice allows therapists to put themselves into their clients' shoes, experiencing the benefits that therapy can bring but also the problems that clients can run in to. This experience increases therapists' empathy for their clients, allowing them to draw on their own experiences in therapy. As a result, therapists tend to feel both more confident in themselves and more competent as a therapist. The self-practice/self-reflection process was facilitated by reflective writing and working with others, particularly peers. Self-practice/self-reflection is a valuable training strategy in CBT, which has a range of beneficial outcomes. It can also be used as a means of continuing personal and professional development. Self-practice of CBT techniques, and reflecting on the process, can be a useful training strategy and helpful for ongoing development Therapists could consider developing a 'self-case' study

A clinical study of space closure with nickel-titanium closed coil springs and an elastic module.

Science.gov (United States)

Samuels, R H; Rudge, S J; Mair, L H

1998-07-01

A previous study has shown that a 150-gram nickel-titanium closed coil spring (Sentalloy, GAC International Inc.) closed spaces more quickly and more consistently than an elastic module (Alastik, Unitec/3M). This study used the same friction sensitive sliding mechanics of pitting the six anterior teeth against the second bicuspid and first molars, to examine the rate of space closure of 100-gram and 200-gram nickel-titanium closed coil springs. The results for the three springs and elastic module were compared. The nickel-titanium closed coil springs produced a more consistent space closure than the elastic module. The 150- and 200-gram springs produced a faster rate of space closure than the elastic module or the 100-gram spring. No significant difference was noted between the rates of closure for the 150- and the 200-gram springs.

Shape Transformation of the Nuclear Envelope during Closed Mitosis.

Science.gov (United States)

Zhu, Qian; Zheng, Fan; Liu, Allen P; Qian, Jin; Fu, Chuanhai; Lin, Yuan

2016-11-15

The nuclear envelope (NE) in lower eukaryotes such as Schizosaccharomyces pombe undergoes large morphology changes during closed mitosis. However, which physical parameters are important in governing the shape evolution of the NE, and how defects in the dividing chromosomes/microtubules are reflected in those parameters, are fundamental questions that remain unresolved. In this study, we show that improper separation of chromosomes in genetically deficient cells leads to membrane tethering or asymmetric division in contrast to the formation of two equal-sized daughter nuclei in wild-type cells. We hypothesize that the poleward force is transmitted to the nuclear membrane through its physical contact with the separated sister chromatids at the two spindle poles. A theoretical model is developed to predict the morphology evolution of the NE where key factors such as the work done by the poleward force and bending and surface energies stored in the membrane have been taken into account. Interestingly, the predicted phase diagram, summarizing the dependence of nuclear shape on the size of the load transmission regions, and the pole-to-pole distance versus surface area relationship all quantitatively agree well with our experimental observations, suggesting that this model captures the essential physics involved in closed mitosis. Copyright © 2016 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Do writing and storytelling skill influence assessment of reflective ability in medical students' written reflections?

Science.gov (United States)

Aronson, Louise; Niehaus, Brian; DeVries, Charlie D; Siegel, Jennifer R; O'Sullivan, Patricia S

2010-10-01

Increasingly, students are asked to write reflections as part of their medical education, but some question the influence of other factors on the evaluation of these reflections. In this pilot study, the investigators determined whether scores from a validated rubric to measure reflective ability were affected by irrelevant variance resulting from writing or storytelling ability. Students in clerkships wrote reflections on professionalism. All were given identical prompts, with half receiving additional structured guidelines on reflection. Sixty reflections, 30 from each group, were randomly chosen and scored for reflection, writing, and storytelling by trained raters using validated rubrics. There was no correlation between reflection and either writing (r = 0.049, P = .35) or storytelling (r = 0.14, P = .13). The guidelines increased reflection, but not writing or storytelling scores. Reflection is a distinct construct unaffected by learners' writing or storytelling skills. These findings support reflective ability as a distinct skill.

Closing remarks

International Nuclear Information System (INIS)

Reig, J.

2007-01-01

Good afternoon. Before providing the closing remarks on behalf of the NEA, I would like to take this opportunity and make some personal reflections, if you allow me Mr. Chairman. I have had the opportunity to take part in the three workshops on public communication organised by the NEA. In the first one in Paris in 2000, representing my country, Spain, and in the two last ones in Ottawa in 2004 and Tokyo today, on behalf of the NEA. The topics for the three workshops follow a logical order, first the focus was on investing in trust in a time when public communication was becoming a big challenge for the regulators. Second, maintaining and measuring public confidence to assess how credible regulators are in front of the public; and finally here in Tokyo, transparency, which is a basic element to achieve trust and credibility. In my view, a regulatory decision has three main components, it has to be technically sound. legally correct and well communicated. The emphasis in the early years was in the technical matters, till legal issues became a key element to achieve the political acceptance from governments and local authorities. Finally the public communication aspects resulted into a major effort and challenge to achieve social acceptance. (author)

A Study of Learners’ Reflection on Andragogical Skills of Distance Education Tutors

Directory of Open Access Journals (Sweden)

Irshad Hussain

2013-01-01

Full Text Available The researcher conducted present study with the objectives to a. evaluate attitude of learners towards academic and tutoring skills of distance education tutors, b. assess the opinion of distance learners about assessment and evaluation skills of their tutors and c. examine reflection of learners on scaffolding skills of distance education tutors. The population of the study consisted of learners of pre-service teacher education (B.Ed semester spring 2010 programme of Allama Iqbal Open University Islamabad. The sample of the study was taken through the convenient sampling technique from three regions of Allama Iqbal Open University situated in the Punjab Province. A questionnaire was designed using a five-point (rating/Likert scale to elicit the reflection of (600 learners. However, the response rate was 78% (468 of the total sample. Interview schedule was also used as a research tool for collecting qualitative data from (50 respondents in five groups. The researcher analysed data quantitatively and qualitatively. The study concluded that the overall reflection of distance learners on andragogical skills of their tutors was positive. Apparently they were satisfied with andragogical skills of their tutors. They asserted that their tutors had academic and tutoring skills (consisting of encouraging, guiding & facilitating –emboldening and enabling skills, assessment & evaluation skills, and technical and social skills. However, tutors needed training to use social websites, Skype and mobile phone conferences and online discussion. Keeping in view the conclusion of the study, the researcher recommended short and long term training of tutors to use information and communication technologies appropriately.

Science policy up close

CERN Document Server

Marburger, John H

2015-01-01

In a career that included tenures as president of Stony Brook University, director of Brookhaven National Laboratory, and science advisor to President George W. Bush, John Marburger (1941 2011) found himself on the front line of battles that pulled science ever deeper into the political arena. From nuclear power to global warming and stem cell research, science controversies, he discovered, are never just about science. Science Policy Up Close" presents Marburger s reflections on the challenges science administrators face in the twenty-first century. In each phase of public service Marburger came into contact with a new dimension of science policy. The Shoreham Commission exposed him to the problem of handling a volatile public controversy over nuclear power. The Superconducting Super Collider episode gave him insights into the collision between government requirements and scientists expectations and feelings of entitlement. The Directorship of Brookhaven taught him how to talk to the public about the risks ...

Algorithm for preparation of multilayer systems with high critical angle of total reflection

International Nuclear Information System (INIS)

Carron, I.; Ignatovich, V.

2002-01-01

The new development of theory of multilayer systems is presented. It shows precisely how to calculate thickness and number of layers to get reflectivity close to unity for a given, in principle, arbitrary critical angle. Application of the new approach to real systems is demonstrated

Diffuse reflectance spectroscopy for monitoring diabetic foot ulcer - A pilot study

Science.gov (United States)

Anand, Suresh; Sujatha, N.; Narayanamurthy, V. B.; Seshadri, V.; Poddar, Richa

2014-02-01

Foot ulceration due to diabetes mellitus is a major problem affecting 12-25% of diabetic subjects in their lifetime. An untreated ulcer further gets infected which causes necrosis leading to amputation of lower extremities. Early identification of risk factors and treatment for these chronic wounds would reduce health care costs and improve the quality of life for people with diabetes. Recent clinical investigations have shown that a series of factors including reduced oxygen delivery and disturbed metabolism have been observed on patients with foot ulceration due to diabetes. Also, these factors can impair the wound healing process. Optical techniques based on diffuse reflectance spectroscopy provide characteristic spectral finger prints shed light on tissue oxygenation levels and morphological composition of a tissue. This study deals with the application of diffuse reflectance intensity ratios based on oxyhemoglobin bands (R542/R580), ratios of oxy- and deoxy-hemoglobin bands (R580/R555), total hemoglobin concentration and hemoglobin oxygen saturation between normal and diabetic foot ulcer sites. Preliminary results obtained are found to be promising indicating the application of reflectance spectroscopy in the assessment of foot ulcer healing.

PRELIMINARY STUDY ON RETRO-REFLECTIVE COATED PAPER BASED ON MICRO-GLASS BEADS

Institute of Scientific and Technical Information of China (English)

YulongWang; ChuanshanZhao; TaoZhang

2004-01-01

High-reflectivity micro-glass bead, as a kind ofretro-reflective material, is widely used in reflectivefabric or film and other reflective coatings. But it israrely used in coated paper. The retro-reflectivetheory of micro-bead is described. Also the effect ofsize of micro-bead, dosage of binder and differentcolor layers on reflective properties of coated paperare discussed in this article. The results show that itsretro-reflective efficiency is good, equally toreflective fabric or film when the micro-glass bead isused in coated paper.

On H-closed and U-closed functions | Cammaroto | Quaestiones ...

African Journals Online (AJOL)

In this article, we extend the work on H-closed functions started by Cammaroto, Fedorchuk and Porter in 1998. Also, U-closed functions are introduced and characterized in terms of filters and adherence. The hereditary and productivity properties are examined and developed for both H-closed and U-closed functions.

"Going out" of the box: Close intercultural friendships and romantic relationships spark creativity, workplace innovation, and entrepreneurship.

Science.gov (United States)

Lu, Jackson G; Hafenbrack, Andrew C; Eastwick, Paul W; Wang, Dan J; Maddux, William W; Galinsky, Adam D

2017-07-01

The present research investigates whether close intercultural relationships promote creativity, workplace innovation, and entrepreneurship-outcomes vital to individual and organizational success. We triangulate on these questions with multiple methods (longitudinal, experimental, and field studies), diverse population samples (MBA students, employees, and professional repatriates), and both laboratory and real-world measures. Using a longitudinal design over a 10-month MBA program, Study 1 found that intercultural dating predicted improved creative performance on both divergent and convergent thinking tasks. Using an experimental design, Study 2 established the causal connection between intercultural dating and creativity: Among participants who had previously had both intercultural and intracultural dating experiences, those who reflected on an intercultural dating experience displayed higher creativity compared to those who reflected on an intracultural dating experience. Importantly, cultural learning mediated this effect. Extending the first 2 studies, Study 3 revealed that the duration of past intercultural romantic relationships positively predicted the ability of current employees to generate creative names for marketing products, but the number of past intercultural romantic partners did not. In Study 4, we analyzed an original dataset of 2,226 professional repatriates from 96 countries who had previously worked in the U.S. under J-1 visas: Participants' frequency of contact with American friends since returning to their home countries positively predicted their workplace innovation and likelihood of becoming entrepreneurs. Going out with a close friend or romantic partner from a foreign culture can help people "go out" of the box and into a creative frame of mind. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Self-reflection, gender and science achievement

Science.gov (United States)

Shoop, Kathleen A.

Drawing on socio-cognitive learning theory, this study compared achievement scores of 134 male and female high school biology students randomly assigned to groups which either used self-reflection, used self-reflection and received feedback, or did not self-reflect. Following a pretest, the teacher provided self-reflection strategy instruction to students in the two intervention groups and then subsequently provided in-class self-reflection time for these groups. The posttest concluded the unit; the retention measure was five weeks later. A quasi-experimental 3 x 3 x 2 (time x intervention x gender) factorial repeated-measures control group design was used for this study; a repeated measures ANOVA and several one-way ANOVA's were used to answer the research questions. Results from the repeated-measures ANOVA revealed significant results for Time and Time x Intervention, with the reflection group demonstrating significantly lower gains from pretest to posttest than the other two groups. The ANOVA examining differences between those who reflected and those who reflected and received feedback provided significant results with similar results for the difference between the control group and the reflection group. For teachers and students this study provides several areas of practical significance. Primarily, teachers may find lower student achievement if students regularly self-reflect but do not receive feedback for their reflection.

Preliminary Study on GF/Carbon/Epoxy Composite Permeability in Designing Close Compartment Processing

Science.gov (United States)

Ya’acob, A. M.; Razali, D. A.; Anwar, U. A.; Radhi, A. H.; Ishak, A. A.; Minhat, M.; Aris, K. D. Mohd; Johari, M. K.; Casey, T.

2018-05-01

This project involves discovering how the permeability effect inside a close compartment in processing. After the appropriate pressure range was found, the close compartment was designed by studying the relationship between pressure output and the flow rate. A variety of pressure ranges have been used in this test to determine the effective pressure range that can be applied to the manufacturing process. Based on the results, the suitable pressure ranges were found between 55 psi to 75 psi. These pressures have been chosen based on the area covered on the product surfaces and time taken to penetrate the proposed area. The relationship between pressure and flow rate have been found to be directly proportional until 75 psi only. In conclusion, 70 psi for the proposed design of close compartment mould is suitable to be used to fulfill the required area of 120 mm square within 90 seconds.

Closing-in behavior: Compensation or attraction?

Science.gov (United States)

Ambron, Elisabetta; Beschin, Nicoletta; Cerrone, Chiara; Della Sala, Sergio

2018-03-01

Closing-in behavior (CIB) defines the abnormal misplacement of the copy performance, positioned very closed to or on the top of the model. This symptom is observed in graphic copying by patients suffering from different neurological diseases, most commonly dementia. The cognitive origins of this behavior are still a matter of investigation, and research of the last 10 years has been focused on exploring 2 main accounts of CIB, the compensation and the attraction hypotheses, providing evidence in both directions. While the first account defines CIB as a compensatory strategy to overcome visuospatial and/or working memory deficits during copying tasks, the attraction hypothesis looks at CIB as primitive default behavior in which attention and action are closely coupled and movements are performed toward the focus of attention. We explored these 2 hypotheses in a sample of patients with and without CIB, and controls in 5 experiments: Experiments 1 and 2 tested the attraction hypothesis and, respectively, the prediction that CIB can be elicited in a noncopying dual task condition loading upon attentional resources or by irrelevant attentional grabbing stimuli. The other experiments investigated the compensation hypothesis manipulating the distance between model and copying space (Experiment 3), the task demand (single or dual task loading on verbal working memory; Experiment 4), the task requirements (copying and tracing) and visual demand (visual copy and memory; Experiment 5). The results support the attraction hypothesis of CIB. CIB reflects an impairment of the attention and action system, rather than a compensatory strategy. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Consistencies far beyond chance: an analysis of learner preconceptions of reflective symmetry

Directory of Open Access Journals (Sweden)

Michael Kainose Mhlolo

2013-01-01

Full Text Available This article reports on regularities observed in learners' preconceptions of reflective symmetry. Literature suggests that the very existence of such regularities indicates a gap between what learners know and what they need to know. Such a gap inhibits further understanding and application, and hence needed to be investigated. A total of 235 Grade 11 learners, from 13 high schools that participate in the First Rand Foundation-funded Mathematics Education project in the Eastern Cape, responded to a task on reflective symmetry. Our framework for analysing the responses was based on the taxonomy of structure of the observed learning outcome. The results indicated that 85% of learner responses reflect a motion understanding of reflections, where learners considered geometric figures as physical motions on top of the plane. While this understanding is useful in some cases, it is not an essential aspect of mapping understanding, which is critical for application in function notations and other analytical geometry contexts. We suggest that if this gap is to be closed, learners need to construct these reflections physically so that they may think of reflections beyond motion.

Tree Canopy Characterization for EO-1 Reflective and Thermal Infrared Validation Studies: Rochester, New York

Science.gov (United States)

Ballard, Jerrell R., Jr.; Smith, James A.

2002-01-01

The tree canopy characterization presented herein provided ground and tree canopy data for different types of tree canopies in support of EO-1 reflective and thermal infrared validation studies. These characterization efforts during August and September of 2001 included stem and trunk location surveys, tree structure geometry measurements, meteorology, and leaf area index (LAI) measurements. Measurements were also collected on thermal and reflective spectral properties of leaves, tree bark, leaf litter, soil, and grass. The data presented in this report were used to generate synthetic reflective and thermal infrared scenes and images that were used for the EO-1 Validation Program. The data also were used to evaluate whether the EO-1 ALI reflective channels can be combined with the Landsat-7 ETM+ thermal infrared channel to estimate canopy temperature, and also test the effects of separating the thermal and reflective measurements in time resulting from satellite formation flying.

Analysis of Wave Reflection from Wave Energy Converters Installed as Breakwaters in Harbour

DEFF Research Database (Denmark)

Zanuttigh, B.; Margheritini, Lucia; Gambles, L.

2009-01-01

loads on the structure, i.e. better survivability. Nevertheless these devices must comply with the requirements of harbour protection structures and thus cope with problems due to reflection of incoming waves, i.e. dangerous sea states close to harbors entrances and intensified sediment scour, which can...

Acceptability of a reflective e-portfolio instituted in an orthodontic specialist programme: a pilot study.

Science.gov (United States)

Tonni, I; Oliver, R G

2013-08-01

The purpose of the study was to highlight students' and mentors' acceptability of a reflective e-portfolio instituted in a postgraduate orthodontic programme in the UK. A reflective e-portfolio was developed on the basis of principles provided by a literature search and was piloted for 2 months with six students and seven mentors. At the end of the experience, mentors' and students' acceptability of the e-portfolio with a reflective component was studied using questionnaires. The data were analysed using basic quantitative and qualitative methods. Students' response highlighted acceptability issues related to each aspect of the e-portfolio derived from the literature: relevance of the e-portfolio reflective part; time required for the process; support and mentoring; the implementation method; and the electronic medium. Mentors showed a more positive attitude towards the e-portfolio, expressing only some concerns about the time involved in using it. Furthermore, the analysis of the data highlighted some other acceptability matters: the specificity of the e-portfolio, the communication amongst students and the relationship between students and mentors. The future successful implementation of the reflective e-portfolio will depend on the productive management of the acceptability issues identified by students and mentors, in particular:(i)the specificity of the e-portfolio that would avoid its overlapping with other part of the programme;(ii)the increasing communication amongst students to improve their knowledge of the reflective writing process; and (iii)the development of a relationship between students and mentors helping to create the appropriate environment for reflection. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Ionic liquids: an x-ray reflectivity study

International Nuclear Information System (INIS)

Sloutskin, E.; Deutsch, M.; Tamam, L.; Ocko, B.; Kuzmenko, I.; Gog, T.

2005-01-01

Full Text:Ionic liquids are non-volatile, non-flammable and thermally stable solvents, and as such are promising 'green' replacements for traditional volatile organic solvents. In the last years hundreds of Ionic liquids were synthesized. Due to the Ionic liquids great industrial potential, this number is growing at an exceedingly fast rate. Despite the great importance of the interfacial properties of materials for technological applications and basic science, the atomic-scale surface structure of the Ionic liquids has never been studied previously. In our study, synchrotron x-ray reflectivity and surface tensiometry were employed to obtain the surface structure and thermodynamics of two ionic liquids, based on the 1-alkyl-3-methylimidazolium cations. A molecular layer of a density ∼18% higher than that of the bulk is found to form at the free surface of these liquids. The excess concentration of the oppositely charged ions within the surface layer is determined by chemical substitution of the anion. Finally, the observed layering at the surface is contrasted with our measurements on the behavior of classical aqueous salt solutions

Reflection in Russian Educational Psychology.

Science.gov (United States)

Nelissen, Jo M. C.; Tomic, Welko

This paper discusses the cultural-historical school founded by Vygotsky, Luria, and Leontiev as the theoretical background of Russian educational psychologists who have been studying how children learn to reflect. Two approaches to reflection are examined within the cultural-historical tradition: first, reflection--like other higher psychological…

Exploring Teacher Beliefs and Classroom Practices through Reflective Practice: A Case Study

Science.gov (United States)

Farrell, Thomas S. C.; Ives, Jessica

2015-01-01

This article presents a case study that explored and reflected on the relationship between the stated beliefs and observed classroom practices of one second language reading teacher. The findings of this study revealed that this particular teacher holds complex beliefs about teaching reading that were evident to some extent in many of his…

Guided and Unguided Student Reflections

OpenAIRE

Matheson, Amanda; Wood, Laura; Franklin, Scott V.

2017-01-01

Self-reflection is important metacognitive skill, enabling students to build coherence into their learning and embed content in a broader context. While various pedagogical techniques exist to encourage student reflection, little research has examined the differences between formally guided, partially guided and unguided reflections. This study focuses on student responses to online Guided Reflection Forms (GRFs) from students in a first-semester non-physics class and, separately, a sophomore...

Reflective Teaching via a Problem Exploration--Teaching Adaptations--Resolution Cycle: A Mixed Methods Study of Preservice Teachers' Reflective Notes

Science.gov (United States)

Hayden, H. Emily; Chiu, Ming Ming

2015-01-01

We explore development of elementary preservice teachers' reflective practices as they solved problems encountered while teaching in a reading clinic. Written reflections (N = 175) were collected across 8 weeks from 23 preservice teachers and analyzed to investigate relationships among problem exploration, teaching adaptations, and problem…

Lower reflectivity and higher minority carrier lifetime of hand-tailored porous silicon

International Nuclear Information System (INIS)

Zhang Nansheng; Ma Zhongquan; Zhou Chengyue; He Bo

2009-01-01

Solar cell grade crystalline silicon with very low reflectivity has been obtained by electrochemically selective erosion. The porous silicon (PS) structure with a mixture of nano- and micro-crystals shows good antireflection properties on the surface layer, which has potential for application in commercial silicon photovoltaic devices after optimization. The morphology and reflectivity of the PS layers are easily modulated by controlling the electrochemical formation conditions (i.e., the current density and the anodization time). It has been shown that much a lower reflectivity of approximately 1.42% in the range 380-1100 nm is realized by using optimized conditions. In addition, the minority carrier lifetime of the PS after removing the phosphorus silicon layer is measured to be ∼3.19 μs. These values are very close to the reflectivity and the minority carrier lifetime of Si 3 N 4 as a passivation layer on a bulk silicon-based solar cell (0.33% and 3.03 μs, respectively).

Microwave reflection properties of planar anisotropy Fe50Ni50 powder/paraffin composites

International Nuclear Information System (INIS)

Wei Jian-Qiang; Zhang Zhao-Qi; Han Rui; Wang Tao; Li Fa-Shen

2012-01-01

The reflection properties of planar anisotropy Fe 50 Ni 50 powder/paraffin composites have been studied in the microwave frequency range. The permeability of Fe 50 Ni 50 powder/paraffin composites is greatly enhanced by introducing the planar anisotropy, and can be further enhanced by using a rotational orientation method. The complex permeability can be considered as the superposition of two types of magnetic resonance. The resonance peak at high frequency is attributed to the natural resonance, while the peak at low frequency is attributed to the domain-wall resonance. The simulated results of the microwave reflectivity show that the matching thickness, peak frequency, permeability, and permittivity are closely related to the quarter wavelength matching condition. The Fe 50 Ni 50 powder/paraffin composites can be attractive candidates for thinner microwave absorbers in the L-band (1–2 GHz). (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Seismic reflection imaging, accounting for primary and multiple reflections

Science.gov (United States)

Wapenaar, Kees; van der Neut, Joost; Thorbecke, Jan; Broggini, Filippo; Slob, Evert; Snieder, Roel

2015-04-01

Imaging of seismic reflection data is usually based on the assumption that the seismic response consists of primary reflections only. Multiple reflections, i.e. waves that have reflected more than once, are treated as primaries and are imaged at wrong positions. There are two classes of multiple reflections, which we will call surface-related multiples and internal multiples. Surface-related multiples are those multiples that contain at least one reflection at the earth's surface, whereas internal multiples consist of waves that have reflected only at subsurface interfaces. Surface-related multiples are the strongest, but also relatively easy to deal with because the reflecting boundary (the earth's surface) is known. Internal multiples constitute a much more difficult problem for seismic imaging, because the positions and properties of the reflecting interfaces are not known. We are developing reflection imaging methodology which deals with internal multiples. Starting with the Marchenko equation for 1D inverse scattering problems, we derived 3D Marchenko-type equations, which relate reflection data at the surface to Green's functions between virtual sources anywhere in the subsurface and receivers at the surface. Based on these equations, we derived an iterative scheme by which these Green's functions can be retrieved from the reflection data at the surface. This iterative scheme requires an estimate of the direct wave of the Green's functions in a background medium. Note that this is precisely the same information that is also required by standard reflection imaging schemes. However, unlike in standard imaging, our iterative Marchenko scheme retrieves the multiple reflections of the Green's functions from the reflection data at the surface. For this, no knowledge of the positions and properties of the reflecting interfaces is required. Once the full Green's functions are retrieved, reflection imaging can be carried out by which the primaries and multiples are

Reflective Practices for Teacher Education

Directory of Open Access Journals (Sweden)

Paulus Kuswandono

2017-01-01

Full Text Available Studies on reflective practice in teacher education are increasingly getting more attention at least in the last 2 decades. This article discusses concepts of reflection and how it is implemented in educating pre-service teachers on their early stage of professional learning. The purposes of doing the reflection for pre-service teachers are not only for illuminating their professional learning experiences, but also to critically reflect their vocation as teachers, including the values which may be dictated to them through rigid regulations. Reflection in teacher education is crucial as it connects well with learning in that learners use reflection to exercise their mind and to evaluate their learning experiences. Besides, this article also highlights some perceived difficulties to implement reflective practice, as well as ways how to promote reflection.   DOI: https://doi.org/10.24071/llt.2012.150102

Reflection during Portfolio-Based Conversations

Science.gov (United States)

Oosterbaan, Anne E.; van der Schaaf, Marieke F.; Baartman, Liesbeth K. J.; Stokking, Karel M.

2010-01-01

This study aims to explore the relationship between the occurrence of reflection (and non-reflection) and thinking activities (e.g., orientating, selecting, analysing) during portfolio-based conversations. Analysis of 21 transcripts of portfolio-based conversations revealed that 20% of the segments were made up of reflection (content reflection…

Design Principles for Closed Loop Supply Chains

NARCIS (Netherlands)

H.R. Krikke (Harold); C.P. Pappis (Costas); G.T. Tsoulfas; J.M. Bloemhof-Ruwaard (Jacqueline)

2001-01-01

textabstractIn this paper we study design principles for closed loop supply chains. Closed loop supply chains aim at closing material flows thereby limiting emission and residual waste, but also providing customer service at low cost. We study 'traditional' and 'new' design principles known in the

Why Kids Need to Be Bored: A Case Study of Self-Reflection and Academic Performance

Science.gov (United States)

Williams, James D.

2006-01-01

This case study involved 3 middle school students in an assessment of the influence of self-reflection on general academic performance. It was hypothesized that increased self-reflection would have a positive influence on academic performance as measured by grades on tests, writing assignments, and homework. The participants were ages 13.4, 13.5,…

Perioperative self-reflection among surgical residents.

Science.gov (United States)

Peshkepija, Andi N; Basson, Marc D; Davis, Alan T; Ali, Muhammad; Haan, Pam S; Gupta, Rama N; Hardaway, John C; Nebeker, Cody A; McLeod, Michael K; Osmer, Robert L; Anderson, Cheryl I

2017-09-01

We studied prevalence and predictors of meaningful self-reflection among surgical residents and with prompting/structured interventions, sought to improve/sustain resident skills. Residents from six programs recorded 1032 narrative self-reflective comments (120 residents), using a web-based platform. If residents identified something learned or to be improved, self-reflection was deemed meaningful. Independent variables PGY level, resident/surgeon gender, study site/Phase1: July2014-August2015 vs. Phase2: September2015-September2016) were analyzed. Meaningful self-reflection was documented in 40.6% (419/1032) of entries. PGY5's meaningfully self-reflected less than PGY1-4's, 26.1% vs. 49.6% (p = 0.002). In multivariate analysis, resident narratives during Phase 2 were 4.7 times more likely to engage in meaningful self-reflection compared to Phase1 entries (p self-reflection, compared to Phase1. Surgical residents uncommonly practice meaningful self-reflection, even when prompted, and PGY5/chief residents reflect less than more junior residents. Substantial/sustained improvements in resident self-reflection can occur with both training and interventions. Copyright © 2017 Elsevier Inc. All rights reserved.

Exchange bias studied with polarized neutron reflectivity

International Nuclear Information System (INIS)

Velthuis, S. G. E. te

2000-01-01

The role of Polarized Neutron Reflectivity (PNR) for studying natural and synthetic exchange biased systems is illustrated. For a partially oxidized thin film of Co, cycling of the magnetic field causes a considerable reduction of the bias, which the onset of diffuse neutron scattering shows to be due to the loosening of the ferromagnetic domains. On the other hand, PNR measurements of a model exchange bias junction consisting of an n-layered Fe/Cr antiferromagnetic (AF) superlattice coupled with an m-layered Fe/Cr ferromagnetic (F) superlattice confirm the predicted collinear magnetization in the two superlattices. The two magnetized states of the F (along or opposite to the bias field) differ only in the relative orientation of the F and adjacent AF layer. The possibility of reading clearly the magnetic state at the interface pinpoints the commanding role that PNR is having in solving this intriguing problem

[Comparative study of reflectance spectroscopy of women's acupoints around menstruation].

Science.gov (United States)

Jiang, Xing-Hui; Liu, Han-Ping; Guo, Zhou-Yi; Meng, Yao-Yong; Zeng, Chang-Chun; Liu, Song-Hao

2010-12-01

Acupoint was reaction of viscera and its optical parameter was an important characteristic of tissue. In the present work, in order to discuss specificity of acupuncture on the response of qi and blood in human body, we compared the diffuse reflectance of Taichong (LV3), Taibai (SP3), and Chongyang (ST42) before, during and after menstruation. All the acupoints had the same shape of the spectrum and troughs were all at 423.16, 544.06 and 577.47 nm. The values of reflectance during menstruation were greater than before and after menstruation, especially for SP3 and ST42 (P menstruation. Diffuse reflectance may be possibly used in the quantitative analysis of qi and blood.

Study of mode locking in a microwave-pumped diode laser close to the generation threshold

International Nuclear Information System (INIS)

Bagaev, Sergei N; Zakharyash, Valerii F; Kashirsky, Aleksandr V; Klementyev, Vasilii M; Kuznetsov, Sergei A; Pivtsov, V S

2004-01-01

Active mode locking is studied in a diode laser with a three-mirror resonator upon the microwave modulation of the pump current. The mode-locking region with the minimal width of the spectrum of intermode beats is found, when the microwave frequency is close to the intermode frequency of an external resonator. This region is shown to be located close to the threshold pump current. (lasers, active media)

Spatial reflection patterns of iridescent wings of male pierid butterflies: curved scales reflect at a wider angle than flat scales.

Science.gov (United States)

Pirih, Primož; Wilts, Bodo D; Stavenga, Doekele G

2011-10-01

The males of many pierid butterflies have iridescent wings, which presumably function in intraspecific communication. The iridescence is due to nanostructured ridges of the cover scales. We have studied the iridescence in the males of a few members of Coliadinae, Gonepteryx aspasia, G. cleopatra, G. rhamni, and Colias croceus, and in two members of the Colotis group, Hebomoia glaucippe and Colotis regina. Imaging scatterometry demonstrated that the pigmentary colouration is diffuse whereas the structural colouration creates a directional, line-shaped far-field radiation pattern. Angle-dependent reflectance measurements demonstrated that the directional iridescence distinctly varies among closely related species. The species-dependent scale curvature determines the spatial properties of the wing iridescence. Narrow beam illumination of flat scales results in a narrow far-field iridescence pattern, but curved scales produce broadened patterns. The restricted spatial visibility of iridescence presumably plays a role in intraspecific signalling.

Close contact dose: a radioiodine therapy case study

International Nuclear Information System (INIS)

Tuchyna, T.

2002-01-01

Full text: External radiation dose rates were measured immediately post administration and periodically thereafter at 0.3 and 1.0 m from a patient who received a 555 MBq therapeutic dose of I-131. The dose received by the partner during the close contact period of sleep was measured with an anthropomorphic RANDO phantom representing a standard man with ICRP60 organs critical for dosimetry. RANDO occupied the same bed as the patient at a skin to skin distance of 30 cm with up to 30 TLD rods (1 x 1 x 6mm, LiF:Mg) inserted at critical organ positions within the phantom. The measurements were compared with empirical estimates provided by the Close Contact Dose Spreadsheet (Cormack and Shearer, 1998). The measured external dose rate of 19.3microSv/hr obtained immediately post administration rose slightly, to 26.3microSv/hr during the first 12 hours, however subsequently demonstrated a slow decrease. The TLDs embed- ded in RANDO recorded a dose of 0.24mSv during the hours of sleep. The total dose received by the partner over the two days was 0.29mSv, which compared favourably with a figure of 0.31mSv obtained by the Close Contact Dose Spreadsheet. The doses received demonstrate the validity of restricting patient partner contact during the hours of sleep within the first few days post administration. Monitoring of the bedroom, bed linen, bathroom, toilet and personal effects showed slight levels of contamination ranging from background to 20 cps. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

Using photographs to study animal social cognition and behaviour: Do capuchins' responses to photos reflect reality?

Science.gov (United States)

Morton, F Blake; Brosnan, Sarah F; Prétôt, Laurent; Buchanan-Smith, Hannah M; O'Sullivan, Eoin; Stocker, Martina; D'Mello, Daniel; Wilson, Vanessa A D

2016-03-01

Behavioural responses to photos are often used to infer what animals understand about their social environment, but are rarely validated against the same stimuli in real life. If subjects' responses to photos do not reflect responses to the same live stimuli, it is difficult to conclude what happens in reality based on photo responses alone. We compared capuchins' responses to photos versus live stimuli in an identical scenario within research cubicles. Subjects had the opportunity to approach food placed in front of an alpha group member and, in a separate condition, photos depicting the same individual. Subjects' latencies to approach food when placed in front of the real alpha negatively correlated with time subjects spent in close proximity to the alpha in their main enclosure. We therefore predicted subjects' latencies to approach food in the presence of photos would positively correlate with their latencies to approach food in the presence of the real alpha inside the cubicles, but negatively correlate with time they spent in proximity to the alpha in their enclosure. Neither prediction was supported. While not necessarily surprising, we explain why these results should be an important reminder that care is needed when interpreting results from photo studies. Copyright © 2015 Elsevier B.V. All rights reserved.

Principals Reflecting on Their Leadership Learning with an Heuristic: A Pilot Study

Science.gov (United States)

Dempster, Neil; Fluckiger, Bev; Lovett, Susan

2012-01-01

The purpose of this paper is to report on a small pilot study in which an heuristic was used to enable principals to reflect on the confidence they have in their existing leadership knowledge and how they might add to that knowledge in the future. The motivation for the study arose from a literature review of strategies for leadership development…

A Multi-wavelength Study of the Close M-dwarf Eclipsing Binary System BX Tri

Science.gov (United States)

Perdelwitz, V.; Czesla, S.; Robrade, J.; Schmitt, J. H. M. M.

2015-01-01

We present the first detailed X-ray study of the close dMe binary system BX Tri, whose optical variation has been continously monitored in the frame of the DWARF project (Pribulla et al.(2012)). We observed BX Tri with XMM-Newton for two full orbital periods and confirm that the system is an ultra-active M-dwarf binary showing frequent flares and an X-ray luminosity close to the saturation limit. The strong magnetic activity could have influenced the angular momentum evolution of the system via magnetic braking.

The use of reflective diaries in end of life training programmes: a study exploring the impact of self-reflection on the participants in a volunteer training programme.

Science.gov (United States)

Germain, Alison; Nolan, Kate; Doyle, Rita; Mason, Stephen; Gambles, Maureen; Chen, Hong; Smeding, Ruthmarijke; Ellershaw, John

2016-03-05

A training programme was developed and delivered to a cohort of volunteers who were preparing for a unique role to provide companionship to dying patients in the acute hospital setting. This comprehensive programme aimed to provide an opportunity for participants to fully understand the nature and responsibilities of the role, whilst also allowing sufficient time to assess the qualities and competencies of participants for their ongoing volunteering role. Participants completed reflective diaries throughout the training course to record their ongoing thoughts and feelings. The purpose of this paper is to present a phenomenological analysis of these entries to understand participants' experiences, perceptions and motivations. The wider study was structured into three phases. Phase 1 was the delivery of a 12 week, bespoke training programme; Phase 2 involved a 26 week pilot implementation of the Care of the Dying Volunteer Service and Phase 3 was the research evaluation of the training and implementation which would inform the further development of the training programme. Self-reflection is a common component of End of Life training programmes and volunteers in this study completed a reflective diary after participation in each of the training sessions. A thematic analysis was undertaken to explore and understand the participants' experience, perceptions and motivations in relation to their participation in the training. All 19 volunteers completed the reflective diaries. From a potential 228 diary entries over the 12 week training programme, 178 diary entries were submitted (78 %). The following key themes were identified: Dying Alone and the importance of being present, Personal loss and the reconstruction of meaning, Self-Awareness and Personal growth, Self-preservation and Coping strategies and group unity/cohesion. The participants in this study demonstrated that they were able to use the diaries as an appropriate medium for reflection. Their reflections were

Shared Relationship Efficacy of Dyad Can Increase Life Satisfaction in Close Relationships: Multilevel Study

Science.gov (United States)

Ito, Kenichi; Yoshida, Toshikazu

2016-01-01

Characteristics of relationship itself play an important role in determining well-being of individuals who participate in the relationship. We used efficacy expectations mutually shared between close friends or romantic partners as a characteristic of relationship and investigated its impact on their life satisfaction. In Study 1, we conducted a cross-sectional study among 137 pairs of close same-sex friends to test whether the efficacy expectations shared between friends are associated with levels of life satisfaction. In Study 2, we conducted a longitudinal study among 114 heterosexual romantic couples to test predictive validity of the efficacy expectations shared between couples predict levels of life satisfaction 2 month later. In both studies we found a consistent result that as degrees of the efficacy expectations shared between individuals in a relationship increased, the degree of their life satisfaction also increased. Underlying mechanisms that explain how characteristics of relationship itself increase life satisfaction are discussed. PMID:27437946

Report on studies on closed cycle MHD power generation; Closed cycle MHD hatsuden kento hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1991-04-01

Summarized herein are results of the studies on closed cycle MHD (CCMHD) power generation by the study committee. The studied system is based on the MHD gas turbine combined Brayton cycle of about 500,000 kW in output power, firing natural gas as the fuel, and the conceptual design works therefor are completed. The major findings are: the overall plant efficiency: 54.2% at the power transmission side, plot area required per unit power output: 0.04 m{sup 2}/KW, unit construction cost: 251,000 yen/KW, and unit power generation cost: 10.2 yen/KWh. This system will be more operable than the gas turbine combined cycle with steam system, because start-up time, output change rate, optimum load and so on are constrained not on the power generator side but on the gas turbine side. The expected environmental effects include the exhaust gas NOX concentration being equivalent with that associated with the conventional power generator of 2-stage combustion system, quantity of combustion gases to be treated being approximately 40% of that associated with the gas turbine combined cycle, and reduced CO2 gas emissions, resulting from enhanced power generation efficiency. It is expected that the CCMHD system can exhibit higher efficiency than the high-temperature gas turbine combined cycle system. (NEDO)

X-ray Reflectivity Study of Ionic Liquids at Electrified Surfaces

Science.gov (United States)

Chu, Miaoqi

X-ray reflectivity (XRR) versatile technique that characterize the surface structures. However, due to the lack of phase information of X-ray data, the reconstruction of electron density profile (EDP) from XRR data is an ill-posed inverse problem that requires extra attention. In Chapter 1, several key concepts in XRR data analysis are reviewed. The typical XRR data acquisition procedure and methods of modeling electron density are introduced. The widely used logarithm form of merit function is justified with mathematical deduction and numerical experiment. A scheme that generates artificial reflectivity data with theoretical statistical error but not systematical error is proposed. With the methods and schemes described in Chapter 1, simulated reflectivity data of a simple one-slab model is generated and fitted to test the efficient of EDP reconstruction. By isolating the parameters, the effects of slab width, electron density contrast and maximal wave transfer are studied individually. It?s demonstrated that best-fit/global minima, result reported by most XRR studies, don?t necessary reflect the real EDP. By contrast, mapping the merit function in the parametric space can capture much more details. Additionally, the widely accepted concept about the XRR theoretical spatial resolution (pi/q_{max}) as well the using Patterson function are brought to test. In the perspective of XRR data analysis, this chapter puts forward general rules to design and optimize XRR experiments. It also demonstrates how susceptible the fitting result will be if it?s not done carefully. In Chapter 3, the interface between hydrophobic OTS film and several solvents is studied with XRR in a transmission-cell setup. The solvents, from water, acetone, to alcohol (methanol, ethanol, 1-propanol), to alkane (pentane, hexane and heptane), vary significantly in terms of polarity and hydrogen bonding. However, the XRR data from different solvents are subtle. The methods and principles elicited in

Study of Cr/Sc-based multilayer reflecting mirrors using soft x-ray reflectivity and standing wave-enhanced x-ray fluorescence

Science.gov (United States)

Wu, Meiyi; Burcklen, Catherine; André, Jean-Michel; Guen, Karine Le; Giglia, Angelo; Koshmak, Konstantin; Nannarone, Stefano; Bridou, Françoise; Meltchakov, Evgueni; Rossi, Sébastien de; Delmotte, Franck; Jonnard, Philippe

2017-11-01

We study Cr/Sc-based multilayer mirrors designed to work in the water window range using hard and soft x-ray reflectivity as well as x-ray fluorescence enhanced by standing waves. Samples differ by the elemental composition of the stack, the thickness of each layer, and the order of deposition. This paper mainly consists of two parts. In the first part, the optical performances of different Cr/Sc-based multilayers are reported, and in the second part, we extend further the characterization of the structural parameters of the multilayers, which can be extracted by comparing the experimental data with simulations. The methodology is detailed in the case of Cr/B4C/Sc sample for which a three-layer model is used. Structural parameters determined by fitting reflectivity curve are then introduced as fixed parameters to plot the x-ray standing wave curve, to compare with the experiment, and confirm the determined structure of the stack.

The Effects of Coaching Using a Reflective Framework on Early Childhood Science Teachers' Depth of Reflection and Change in Practice

Science.gov (United States)

Bloomquist, Debra L.

This embedded-mixed methods study examined if the use of a reflective framework with guiding prompts could support early childhood science teachers in improving their reflective practice and subsequently changing their pedagogy. It further investigated whether type of cognitive coaching group, individual or collaborative, impacted teacher depth of reflection and change in practice. Data included teacher reflections that were rated using the Level of Reflection-On-Action Assessment, reflective codes and inductive themes, as well as videos of participants lessons coded using the SCIIENCE instrument. Findings demonstrated that through guided reflection, teachers developed reflective thinking skills, and through this reflection became more critical and began to improve their pedagogical practice. Further findings supported that collaborative cognitive coaching may not be the most effective professional development for all teachers; as some teachers in the study were found to have difficulty improving their reflectivity and thus their teaching practice. Based on these findings it is recommended that coaches and designers of professional development continue to use reflective frameworks with guiding prompts to support teachers in the reflective process, but take into consideration that coaching may need to be differentiated for the various reflective levels demonstrated by teachers. Future studies will be needed to establish why some teachers have difficulty with the reflective process and how coaches or designers of professional development can further assist these teachers in becoming more critical reflectors.

Being a reflective teacher——reflection on group management

Institute of Scientific and Technical Information of China (English)

Pan; Lehui

2015-01-01

<正>Introduction According to Pollard and Triggs(1997),reflective teaching is a process through which the capacity to make such professional judgments can be developed and maintained.Then what is a reflective teacher?Reflective teacher is someone who reflects systematically on her practice in a constant attempt to improve

Studies of short-lived nuclei in the proximity of closed shells

International Nuclear Information System (INIS)

Omtvedt, J.P.

1995-01-01

In this work the structure of 84,85 Se at the closed N=50 neutron shell, and the 132 Sb, 132 Sn, and 134 Te nuclei, at the doubly closed N=82,Z=50 shells, was studied. The experiments were performed at the OSIRIS fission product mass separator at Studsvik, Sweden. The excited levels of the studied nuclei were populated in β decay. The sources were produced in fission of 235 U in the OSIRIS combined target and ion source. The nuclei were studied by standard nuclear spectroscopy measuring techniques: Singles γ spectra and γγ-coincidence data were obtained. In addition γγ(θ) angular correlation and βγγ(t) triple coincidence ''fast-timing'' ,measurements were performed on the nuclei in the 132 Sn (N=82,Z=50) region. Detailed level schemes for the 84,85 Se, 132 Sb, 132 Sn, 132 Te nuclei were built, greatly improvi our knowledge of the structure of these nuclei. The experimentally deduced transition rates and multipole mixing ratios of the studied 132 Sn region nuclei were compared to theoretical calculations within the random phase approximation framework and related models. Particular attention was paid to the collective properties of nuclei in the 132 Sn region, parametrized by the electrical octupole effective charge. A range of general software spectroscopic tools were developed for the purpose of analysing the experimental data. This included a program, Yggdrasil, which for the first time allowed a complete two-dimensional γγ-coincidence matrix to be analysed on ordinary ''small'' personal computers (PCs). 49 refs., 10 figs., 2 tabs

High-Altitude Closed Magnetic Loops at Mars Observed by MAVEN

Science.gov (United States)

Xu, Shaosui; Mitchell, David; Luhmann, Janet; Ma, Yingjuan; Fang, Xiaohua; Harada, Yuki; Hara, Takuya; Brain, David; Weber, Tristan; Mazelle, Christian; DiBraccio, Gina A.

2017-11-01

With electron and magnetic field data obtained by the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, we have identified closed magnetic field lines, with both foot points embedded in the dayside ionosphere, extending up to 6,200 km altitude into the Martian tail. This topology is deduced from photoelectrons produced in the dayside ionosphere being observed traveling both parallel and antiparallel to the magnetic field. At trapped-zone pitch angles (within a range centered on 90° where electrons magnetically reflect before interacting with the atmosphere), cases with either solar wind electrons or photoelectrons have been found, indicating different formation mechanisms for these closed loops. These large closed loops are present in MHD simulations. The case with field-aligned photoelectrons mixed with solar wind electrons having trapped-zone pitch angles is likely to be associated with reconnection, while the case with photoelectrons at all pitch angles is probably due to closed field lines being pulled tailward by the surrounding plasma flow. By utilizing an algorithm for distinguishing photoelectrons from solar wind electrons in pitch angle-resolved energy spectra, we systematically map the spatial distribution and occurrence rate of these closed magnetic loops over the region sampled by the MAVEN orbit. We find that the occurrence rate ranges from a few percent to a few tens of percent outside of the optical shadow and less than one percent within the shadow. These observations can be used to investigate the general magnetic topology in the tail, which is relevant to cold ion escape, reconnection, and flux ropes.

Cognitive Reflection and the Diligent Worker: An Experimental Study of Millennials.

Directory of Open Access Journals (Sweden)

Brice Corgnet

Full Text Available Recent studies have shown that despite crucially needing the creative talent of millennials (people born after 1980 organizations have been reluctant to hire young workers because of their supposed lack of diligence. We propose to help resolve this dilemma by studying the determinants of task performance and shirking behaviors of millennials in a laboratory work environment. We find that cognitive ability is a good predictor of task performance in line with previous literature. In contrast with previous research, personality traits do not consistently predict either task performance or shirking behaviors. Shirking behaviors, as measured by the time participants spent browsing the internet for non-work purposes (Cyberloafing, were only explained by the performance on the Cognitive Reflection Test (CRT. This finding echoes recent research in cognitive psychology according to which conventional measures of cognitive ability only assess a narrow concept of rational thinking (the algorithmic mind that fails to capture individuals' capacity to reflect and control their impulses. Our findings suggest that hiring diligent millennials relies on the use of novel cognitive measures such as CRT in lieu of standard personality and intelligence tests.

Cognitive Reflection and the Diligent Worker: An Experimental Study of Millennials.

Science.gov (United States)

Corgnet, Brice; Hernán Gonzalez, Roberto; Mateo, Ricardo

2015-01-01

Recent studies have shown that despite crucially needing the creative talent of millennials (people born after 1980) organizations have been reluctant to hire young workers because of their supposed lack of diligence. We propose to help resolve this dilemma by studying the determinants of task performance and shirking behaviors of millennials in a laboratory work environment. We find that cognitive ability is a good predictor of task performance in line with previous literature. In contrast with previous research, personality traits do not consistently predict either task performance or shirking behaviors. Shirking behaviors, as measured by the time participants spent browsing the internet for non-work purposes (Cyberloafing), were only explained by the performance on the Cognitive Reflection Test (CRT). This finding echoes recent research in cognitive psychology according to which conventional measures of cognitive ability only assess a narrow concept of rational thinking (the algorithmic mind) that fails to capture individuals' capacity to reflect and control their impulses. Our findings suggest that hiring diligent millennials relies on the use of novel cognitive measures such as CRT in lieu of standard personality and intelligence tests.

Cognitive Reflection and the Diligent Worker: An Experimental Study of Millennials

Science.gov (United States)

Corgnet, Brice; Hernán Gonzalez, Roberto; Mateo, Ricardo

2015-01-01

Recent studies have shown that despite crucially needing the creative talent of millennials (people born after 1980) organizations have been reluctant to hire young workers because of their supposed lack of diligence. We propose to help resolve this dilemma by studying the determinants of task performance and shirking behaviors of millennials in a laboratory work environment. We find that cognitive ability is a good predictor of task performance in line with previous literature. In contrast with previous research, personality traits do not consistently predict either task performance or shirking behaviors. Shirking behaviors, as measured by the time participants spent browsing the internet for non-work purposes (Cyberloafing), were only explained by the performance on the Cognitive Reflection Test (CRT). This finding echoes recent research in cognitive psychology according to which conventional measures of cognitive ability only assess a narrow concept of rational thinking (the algorithmic mind) that fails to capture individuals’ capacity to reflect and control their impulses. Our findings suggest that hiring diligent millennials relies on the use of novel cognitive measures such as CRT in lieu of standard personality and intelligence tests. PMID:26545244

Supporting Teacher Reflection through Online Discussion

Directory of Open Access Journals (Sweden)

Jiening Ruan

2011-12-01

Full Text Available The purpose of this case study was to investigate online discussion as a means to promote critical reflection. The study was conducted during a semester-long graduate course on issues related to literacy instructional strategies. The participants in the study were four reading education candidates. During the semester they participated in online discussion about course readings and reflected on their own teaching experiences. The data sources were the online discussion postings, responses to questionnaires, and interviews. The results suggest that technology-mediated discussion strengthens the learning community, facilitates sharing of professional experience among participants, and enhances teacher reflection. The results also point to the multi-faceted nature of teacher reflection.

The thermal history of the Bowen Basin: a comparison of apatite fission track analysis and vitrinite reflectance

International Nuclear Information System (INIS)

Marshallsea, S.J.

1987-01-01

Vitrinite reflectance and apatite fission-track analysis (AFTA) are two techiques widely used to assess paleotemperatures of the order of 20-120 deg.C. in sedimentary basins. Whereas vitrinite reflectance is essentially a qualitative technique that gives an integrated measure of the entire thermal history, AFTA can reveal information on the variation of paleotemperatures through time because fission-tracks in apatite are continually produced throughout geological time. An apatite fission track study of the Upper Permian units of the Bowen Basin has offered the opportunity to compare the two paleotemperature indicators and place constraints on the timing of maximum paleotemperatures. The regional pattern of apatite fission-track ages closely coincides with the vitrinite reflectance indicating that maximum paleotemperatures have varied across the Basin with the central region of the Bowen Basin experiencing highest paleotemperatures. The reduction in apatite reflectance fission-track age with increasing reflectance represents the progressive annealing at temperatures around 60-120 deg. C. of those fission-tracks formed prior to the time of maximum temperatures. In those samples giving the youngest apatite fission-track ages all tacks were totally annealed at this time, and the fission-track age in these samples, in the range 90-120 Myr, indicate the time of cooling from the thermal maximum in the Early Cretaceous. 1 ref

Study of the laser-induced damage of reflective components in the sub-picosecond regime

International Nuclear Information System (INIS)

Sozet, Martin

2016-01-01

In this thesis, laser-induced damage phenomenon of reflective components is investigated in the sub-picosecond regime. These components, made of stacks of dielectric materials, are widely used in powerful laser facilities such as PETAL laser. PETAL laser has been built at the CEA-CESTA in France to deliver multi-kJ/500 fs pulses at 1053 nm and reach a power higher than 6 PW. For this kind of laser systems, reflective components are commonly used instead of optics operating in transmission to limit the accumulation of non-linear phase along the beam propagation due to the high intensities. Optical components irradiated by the highest power densities are the pulse compression gratings, transport mirrors and the focusing parabola, located at the end of the laser chain. Nowadays, laser-induced damage is the main factor that limits the overall performances of powerful laser systems. This manuscript presents three study axes to better understand and control damage phenomenon. The first one concerns the conception of reflective optics for the peta-watt applications. The design of new structures has been investigated to reach high diffraction efficiencies in the case of pulse compression gratings and a high reflectivity in the case of mirrors, while reducing the Electric-field enhancement which is one of the causes of the laser-induced damage. The second axis deals with the development of a precise damage metrology with new testing tools which brings new perspectives and a new viewpoint for the assessment of the laser resistance of optical components. Finally, the third axis concerns the study the damage growth after several irradiations in the sub-picosecond regime. The evolution of the damage area during growth sequences is observed and compared to numerical simulations. It enables to improve the understanding in the growth phenomenon. In the end, these studies will allow to develop predictive models of the laser-induced damage and new tools for the conception of

Barriers to learning from reflection: a study of the use of groupwork with post-registration nurses.

Science.gov (United States)

Platzer, H; Blake, D; Ashford, D

2000-05-01

There are few studies which describe the use of groups to facilitate reflection and even fewer which evaluate the effectiveness of such groups. Much of the literature discussing the techniques used to facilitate reflection suggests that learners willingly engage in such processes and find them enjoyable. This paper reports on a qualitative study of the use of groups to develop learning through reflection on a part-time post-registration diploma programme for nurses. The findings suggest that there are many barriers to learning which must be overcome before practitioners can use the opportunities to reflect on and learn from their experience. It is also contended that such learning may not necessarily be an enjoyable experience. The findings suggest that previous educational experience and the current culture in which nurses and midwives work, impose tremendous barriers to reflecting on, and learning from, experience. In particular these affect the willingness of learners to expose themselves to the judgement of others and their ability to be open to taking responsibility for their own learning. Other barriers to learning in groups are the effects of other group members, their commitment or resistance to shared learning, the ways in which group members interact with each other and facilitation styles.

Validating the Persian Version of Reflective Thinking Questionnaire and Probing Iranian University Students' Reflective Thinking and Academic Achievement

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Afsaneh Ghanizadeh

2017-07-01

Full Text Available Scholars in higher education deem reflective thinking as integral to the development of professional disciplinary practices. One of the major issues in studying reflective thinking pivots around its conceptualization and assessment. Over the years, researchers have used several methods and scales to measure reflective thinking. One of the most widely known scales of reflective thinking was constructed and validated by Kember et al. (2000. It is entitled 'Reflective Thinking Questionnaire (RTQ' and includes 16 items measuring four types of reflective thinking: understanding (UND; reflection (REF; critical reflection (CREF; habitual action (HA. The present study aimed at validating the Persian version of RTQ among one hundred ninety six English as a foreign language (EFL university students. It then scrutinized the role of reflective thinking in academic achievements measured by grade point average (GPA. The association of learners' reflective thinking style with their educational level and gender was also estimated. To conduct the research, the scale was first translated into Persian and its validity (computed via confirmatory factor analysis, convergent, and divergent validity estimates and reliability (computed via Cronbach's alpha were substantiated. It was indicated that among the comprising factors of reflective thinking, UND received the highest mean followed by REF and CREF

Studies on the detection of concealed objects using the neutron reflection method

International Nuclear Information System (INIS)

Papp, A.

2013-01-01

The increment of reflected thermal and 1.45 eV resonance neutrons vs. the thickness of the reflector has been measured and described by an analytical expression. Macroscopic, Σ β , and microscopic, σ β , reflection cross sections averaged over the bulk reflector substances were deduced for some elements and compounds. It was found that the σ β values are additive even for bulk samples and so the σ βmol could be given for some illicit drugs, explosives and hiding materials. - Highlights: ► The effect of reflector materials on the increment of neutrons were determined. ► Macroscopic and microscopic reflection cross sections averaged over bulk samples were determined. ► Simple analytical expression was given to describe the yield of reflected neutrons. ► The observed additive behavior in reflected neutrons rendered to characterize other materials

Laser Sensing of Vegetation Based on Dual Spectrum Measurements of Reflection Coefficients

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M. L. Belov

2017-01-01

Full Text Available Currently, a promising trend in remote sensing of environment is to monitor the vegetative cover: evaluate the productivity of agricultural crops; evaluate the moisture content of soils and the state of ecosystems; provide mapping the sites of bogging, desertification, drought, etc.; control the phases of vegetation of crops, etc.Development of monitoring systems for remote detection of vegetation sites being under unfavorable conditions (low or high temperature, excess or lack of water, soil salinity, disease, etc. is of relevance. Optical methods are the most effective for this task. These methods are based on the physical features of reflection spectra in the visible and near infrared spectral range for vegetation under unfavorable conditions and vegetation under normal conditions.One of the options of optoelectronic equipment for monitoring vegetation condition is laser equipment that allows remote sensing of vegetation from the aircraft and mapping of vegetation sites with abnormal (inactive periods of vegetation reflection spectra with a high degree of spatial resolution.The paper deals with development of a promising dual-spectrum method for laser remote sensing of vegetation. Using the experimentally measured reflection spectra of different vegetation types, mathematical modeling of probability for appropriate detection and false alarms to solve a problem of detecting the vegetation under unfavorable conditions (with abnormal reflection spectra is performed based on the results of dual-spectrum measurements of the reflection coefficient.In mathematical modeling, the lidar system was supposed to provide sensing at wavelengths of 0.532 μm and 0.85 μm. The noise of the measurement was supposed to be normal with zero mean value and mean-square value of 1% -10%.It is shown that the method of laser sensing of vegetation condition based on the results of dual-spectrum measurement of the reflection coefficient at wavelengths of 0.532 μm and 0

a Comparative Case Study of Reflection Seismic Imaging Method

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Alamooti, M.; Aydin, A.

2017-12-01

Seismic imaging is the most common means of gathering information about subsurface structural features. The accuracy of seismic images may be highly variable depending on the complexity of the subsurface and on how seismic data is processed. One of the crucial steps in this process, especially in layered sequences with complicated structure, is the time and/or depth migration of seismic data.The primary purpose of the migration is to increase the spatial resolution of seismic images by repositioning the recorded seismic signal back to its original point of reflection in time/space, which enhances information about complex structure. In this study, our objective is to process a seismic data set (courtesy of the University of South Carolina) to generate an image on which the Magruder fault near Allendale SC can be clearly distinguished and its attitude can be accurately depicted. The data was gathered by common mid-point method with 60 geophones equally spaced along an about 550 m long traverse over a nearly flat ground. The results obtained from the application of different migration algorithms (including finite-difference and Kirchhoff) are compared in time and depth domains to investigate the efficiency of each algorithm in reducing the processing time and improving the accuracy of seismic images in reflecting the correct position of the Magruder fault.

Decision-making in palliative care: a reflective case study.

Science.gov (United States)

Birchall, Melissa

2005-01-01

Critical examination of the processes by which we as nurses judge and reach clinical decisions is important. It facilitates the maintenance and refinement of good standards of nursing care and the pinpointing of areas where improvement is needed. In turn this potentially could support broader validation of nurse expertise and contribute to emancipation of the nursing profession. As pure theory, clinical decision-making may appear abstract and alien to nurses struggling in 'the swampy lowlands' (Schon 1983) of the realities of practice. This paper explores some of the key concepts in decision-making theory by introducing, then integrating, them in a reflective case study. The case study, which examines a 'snapshot' of the patient and practitioner's journey, interwoven with theory surrounding clinical decision-making, may aid understanding and utility of concepts and theories in practice.

The legacy of Biosphere 2 for the study of biospherics and closed ecological systems.

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Allen, J P; Nelson, M; Alling, A

2003-01-01

The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics, led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review accomplishments and challenges, citing some of the key research findings and publications that have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of atmospheric leak detection and sealing, while achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trace gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal biogeochemical cycling and ranges of atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained with good health with lowered atmospheric oxygen levels could lead to major economies on the design of space stations and

The legacy of biosphere 2 for the study of biospherics and closed ecological systems

Science.gov (United States)

Allen, J. P.; Nelson, M.; Alling, A.

The unprecedented challenges of creating Biosphere 2, the world's first laboratory for biospherics, the study of global ecology and long-term closed ecological system dynamics, led to breakthrough developments in many fields, and a deeper understanding of the opportunities and difficulties of material closure. This paper will review accomplishments and challenges, citing some of the key research findings and publications that have resulted from the experiments in Biosphere 2. Engineering accomplishments included development of a technique for variable volume to deal with pressure differences between the facility and outside environment, developing methods of atmospheric leak detection and sealing, while achieving new standards of closure, with an annual atmospheric leakrate of less than 10%, or less than 300 ppm per day. This degree of closure permitted detailed tracking of carbon dioxide, oxygen, and trice gases such as nitrous oxide and ethylene over the seasonal variability of two years. Full closure also necessitated developing new approaches and technologies for complete air, water, and wastewater recycle and reuse within the facility. The development of a soil-based highly productive agricultural system was a first in closed ecological systems, and much was learned about managing a wide variety of crops using non-chemical means of pest and disease control. Closed ecological systems have different temporal biogeochemical cycling and ranges of atmospheric components because of their smaller reservoirs of air, water and soil, and higher concentration of biomass, and Biosphere 2 provided detailed examination and modeling of these accelerated cycles over a period of closure which measured in years. Medical research inside Biosphere 2 included the effects on humans of lowered oxygen: the discovery that human productivity can be maintained with good health with lowered atmospheric oxygen levels could lead to major economies on the design of space stations and

Acousto-optic control of internal acoustic reflection in tellurium dioxide crystal in case of strong elastic energy walkoff [Invited].

Science.gov (United States)

Voloshinov, Vitaly; Polikarpova, Nataliya; Ivanova, Polina; Khorkin, Vladimir

2018-04-01

Peculiar cases of acoustic wave propagation and reflection may be observed in strongly anisotropic acousto-optical crystals. A tellurium dioxide crystal serves as a prime example of such media, since it possesses record indexes of acoustic anisotropy. We studied one of the unusual scenarios of acoustic incidence and reflection from a free crystal-vacuum boundary in paratellurite. The directions of the acoustic waves in the (001) plane of the crystal were determined, and their basic characteristics were calculated. The carried-out acousto-optic experiment at the wavelength of light 532 nm and the acoustic frequency 73 MHz confirmed the theoretical predictions. The effects examined in the paper include the acoustic wave propagation with the record walkoff angle 74°. We also observed the incidence of the wave on the boundary at the angle exceeding 90°. Finally, we registered the close-to-back reflection of acoustic energy following the incidence. One of the stunning aspects is the distribution of energy between the incident and the back-reflected wave. The unusual features of the acoustic wave reflections pointed out in the paper are valuable for their possible applications in acousto-optic devices.

Transition from Clinical Manager to University Lecturer: A Self-Reflective Case Study

Science.gov (United States)

Oldland, Elizabeth

2011-01-01

This paper is a case study exploring the author's use of reflective practice to facilitate the transition in role from a clinical manager with teaching responsibilities in a critical care unit to university lecturer. The similarities and differences in the roles with respect to learner characteristics, teaching contexts and effective teaching…

Reflections on Tutoring Ancient Greek Philosophy: A Case Study of Teaching First-Year Undergraduates in the UK

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Vázquez, Daniel

2014-01-01

This is a case study of my reflections on teaching a first-year undergraduate tutorial on Ancient Greek Philosophy in the UK. This study draws upon the notion of reflective practice as an essential feature of teaching, in this case applied to Higher Education. My aim is to show how a critical engagement with my teaching practices and the overall…

Technological Advancement in Tower-Based Canopy Reflectance Monitoring: The AMSPEC-III System.

Science.gov (United States)

Tortini, Riccardo; Hilker, Thomas; Coops, Nicholas C; Nesic, Zoran

2015-12-19

Understanding plant photosynthesis, or Gross Primary Production (GPP), is a crucial aspect of quantifying the terrestrial carbon cycle. Remote sensing approaches, in particular multi-angular spectroscopy, have proven successful for studying relationships between canopy-reflectance and plant-physiology processes, thus providing a mechanism to scale up. However, many different instrumentation designs exist and few cross-comparisons have been undertaken. This paper discusses the design evolution of the Automated Multiangular SPectro-radiometer for Estimation of Canopy reflectance (AMSPEC) series of instruments. Specifically, we assess the performance of the PP-Systems Unispec-DC and Ocean Optics JAZ-COMBO spectro-radiometers installed on an updated, tower-based AMSPEC-III system. We demonstrate the interoperability of these spectro-radiometers, and the results obtained suggest that JAZ-COMBO can successfully be used to substitute more expensive measurement units for detecting and investigating photosynthesis and canopy spectra. We demonstrate close correlations between JAZ-COMBO and Unispec-DC measured canopy radiance (0.75 ≤ R² ≤ 0.85) and solar irradiance (0.95 ≤ R² ≤ 0.96) over a three month time span. We also demonstrate close agreement between the bi-directional distribution functions obtained from each instrument. We conclude that cost effective alternatives may allow a network of AMSPEC-III systems to simultaneously monitor various vegetation types in different ecosystems. This will allow to scale and improve our understanding of the interactions between vegetation physiology and spectral characteristics, calibrate broad-scale observations to stand-level measurements, and ultimately lead to improved understanding of changing vegetation spectral features from satellite.

Reflection seismic methods applied to locating fracture zones in crystalline rock

International Nuclear Information System (INIS)

Juhlin, C.

1998-01-01

The reflection seismic method is a potentially powerful tool for identifying and localising fracture zones in crystalline rock if used properly. Borehole sonic logs across fracture zones show that they have reduced P-wave velocities compared to the surrounding intact rock. Diagnostically important S-wave velocity log information across the fracture zones is generally lacking. Generation of synthetic reflection seismic data and subsequent processing of these data show that structures dipping up towards 70 degrees from horizontal can be reliably imaged using surface seismic methods. Two real case studies where seismic reflection methods have been used to image fracture zones in crystalline rock are presented. Two examples using reflection seismic are presented. The first is from the 5354 m deep SG-4 borehole in the Middle Urals, Russia where strong seismic reflectors dipping from 25 to 50 degrees are observed on surface seismic reflection data crossing over the borehole. On vertical seismic profile data acquired in the borehole, the observed P-wave reflectivity is weak from these zones, however, strong converted P to S waves are observed. This can be explained by the source of the reflectors being fracture zones with a high P wave to S wave velocity ratio compared to the surrounding rock resulting in a high dependence on the angle of incidence for the reflection coefficient. A high P wave to S wave velocity ratio (high Poisson's ratio) is to be expected in fluid filled fractured rock. The second case is from Aevroe, SE Sweden, where two 1 km long crossing high resolution seismic reflection lines were acquired in October 1996. An E-W line was shot with 5 m geophone and shotpoint spacing and a N-S one with 10 m geophone and shotpoint spacing. An explosive source with a charge size of 100 grams was used along both lines. The data clearly image three major dipping reflectors in the upper 200 ms (600 m). The dipping ones intersect or project to the surface at/or close to

Parametric Analysis of Acoustical Requirements for Lateral Reflections: Melbourne Recital Hall Case Study

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Erica Claustro

2013-06-01

Full Text Available This paper is an investigation of the Melbourne Recital Centre as a case study to define the parameters necessary for good acoustical quality as it relates to the Binaural Quality Index and determining the intimacy of the hall by its initial time delay gap. The Melbourne Recital Centre, designed by Ashton Raggatt McDougall Architects, is a significant case study, as its design was driven by the acoustic requirements of reflection and diffusion through Odeon Acoustical Software. It achieves the same acoustical quality of older, ornately designed shoebox concert halls, from the perspective of contemporary design and fabrication tools and techniques. The sleek design of the Melbourne Recital Centre successfully reflects sound waves in low, mid, and high frequencies due to corresponding wall panel differentiation in the corresponding scales, as engineered by Arup Acoustics.

Comparison between arc drops in ignited thermionic converters with and without ion reflections at the emitter

International Nuclear Information System (INIS)

Lundgren, L.

1985-01-01

The output performance of two thermionic energy converters is compared. One converter has a normal emitter, working with zero field at the emitter which is close to the optimum working point, and the other has a low work function emitter and ion reflection at the emitter. A simple model of the plasma and the sheaths shows that a converter working with a low work function emitter and ion reflections gives a worse performance than a similar converter with a normal emitter

Closing the Gap: some unsettling assumptions - A remote region case study

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Ann Ingamells

2010-04-01

Full Text Available Australian governments are committed to closing the gap between Indigenous and other Australians, yet progress is slow. This paper draws links between these policy efforts and a study of a remote shire in Western Queensland where indicators suggest better than usual socioeconomic outcomes for Aboriginal people. The study conducted over a three year period, and with significant input from Aboriginal people, examines the pathway through which these outcomes have been achieved. Local accounts suggest relations between long term families of both cultures have been a significant factor and are the outcome of an iterative dynamic between people, place and resources, that has a long history, and path dependence. Despite almost full engagement of Aboriginal people in employment over the past 100 years however, indicators do not yet converge, suggesting policy targets are ambitious. The persistent ‘gap’ may be the effect of insistence on making equality conditional on acceptance of settler norms, at significant cost to the lived expression of Aboriginal culture. Whilst this community has managed these tensions, nevertheless their experiences imply that access to community services in remote areas, rather than being a right, is precariously dependent on the vicissitudes of relationship, and these may often depend on the choices Aboriginal people make in response to assimilatory pressures. Keywords: 'Closing the Gap', remote settlements, Aboriginal, Indigenous, intervention, governmentality

Specular reflectance of soiled glass mirrors - Study on the impact of incidence angles

Science.gov (United States)

Heimsath, Anna; Lindner, Philip; Klimm, Elisabeth; Schmid, Tobias; Moreno, Karolina Ordonez; Elon, Yehonatan; Am-Shallem, Morag; Nitz, Peter

2016-05-01

The accumulation of dust and soil on the surface of solar reflectors is an important factor reducing the power output of solar power plants. Therefore the effect of accumulated dust on the specular reflectance of solar mirrors should be understood well in order to improve the site-dependent performance prediction. Furthermore, an optimization of the CSP System maintenance, in particular the cleaning cycles, can be achieved. Our measurements show a noticeable decrease of specular reflectance when the angle of incidence is increased. This effect may be explained by shading and blocking mechanisms caused by dirt particles. The main physical causes of radiation loss being absorption and scattering, the near-angle scattering leads to a further decrease of specular reflectance for smaller angles of acceptance. Within this study mirror samples were both outdoor exposed and indoor artificially soiled. For indoor soiling, the mirror samples were artificially soiled in an in-house developed dusting device using both artificial-standardized dust and real dust collected from an arid outdoor test field at the Negev desert. A model function is proposed that approximates the observed reduction of specular reflectance with the incidence angle with a sufficient accuracy and by simple means for this soil type. Hence a first step towards a new approach to improve site dependent performance prediction of solar power plants is taken.

StarClose Vascular Closure Device: Prospective Study on 222 Deployments in an Interventional Radiology Practice

International Nuclear Information System (INIS)

Imam, Atique; Carter, Ranjana M. S.; Phillips-Hughes, Jane; Boardman, Philip; Uberoi, Raman

2007-01-01

The StarClose device (Abbott Vascular Devices; Abbott Laboratories, Redwood City, CA) utilizes an externally placed Nitinol clip to achieve arterial closure following femoral artery puncture. The objectives of this study were to assess the efficacy and complications of the StarClose device in patients undergoing interventional radiological procedures. Preprocedural clotting status, pulse and blood pressure, severity of vessel calcification, sheath size, and time to deployment were recorded. Postdeployment complications immediately postprocedure, at 1 h, at 2 h, and at 1 week were recorded. A duplex scan was performed in the first 10 patients to assess any immediate vascular complications. Deployments were successful in 96% achieving immediate hemostasis. Mean deployment time was 48 s. There were no major complications. The StarClose device was found to have a high technical and clinical efficacy

The Experience of Critical Self-Reflection by Life Coaches: A Phenomenological Study

Science.gov (United States)

Shaw, Deanna Lynn

2012-01-01

The purpose of this study was to describe the experience of critical self-reflection by life coaches. Life coaching is expanding within many disciplines including education, health care, business, social work, and wellness. Life coaching involves a coach working with an individual or groups aimed at effecting change for professional and personal…

The Influence of Collaborative Reflection and Think-Aloud Protocols on Pre-Service Teachers' Reflection: A Mixed Methods Approach

Science.gov (United States)

Epler, Cory M.; Drape, Tiffany A.; Broyles, Thomas W.; Rudd, Rick D.

2013-01-01

The purpose of this mixed methods study was to determine if there are differences in pre-service teachers' depth of reflection when using a written self-reflection form, a written self-reflection form and a think-aloud protocol, and collaborative reflection. Twenty-six pre-service teachers were randomly assigned to fourteen teaching teams. The…

Studies of effects of closed microbial ecology. Report of 180-day test period

Science.gov (United States)

Kenyon, A. J.

1972-01-01

Experiments were performed to determine the influence closed microbial ecologies have on modification or simplification of natural intestinal flora of ferrets in a closed environmental system. On the basis of previous tests in which certain species (Salmonella and Bacteroides) were decreased at 90 days of enclosure, a second trial was constructed for 180-day tests. In this trial there was little difference in the 8 major classes of intestinal flora between animals in the Open and Closed environmental groups except for the level of Lactobacillus. It is of extreme importance to note that when both Open and Closed groups contracted hemorrhagic gastritis, the interrelationship of this agent with other intestinal flora produced a more profound effect on animals from the Closed Group, particularly with reference to Lactobacillus levels.

Studies of short-lived nuclei in the proximity of closed shells

Energy Technology Data Exchange (ETDEWEB)

Omtvedt, J.P.

1995-12-31

In this work the structure of {sup 84,85}Se at the closed N=50 neutron shell, and the {sup 132}Sb, {sup 132}Sn, and {sup 134}Te nuclei, at the doubly closed N=82,Z=50 shells, was studied. The experiments were performed at the OSIRIS fission product mass separator at Studsvik, Sweden. The excited levels of the studied nuclei were populated in {beta} decay. The sources were produced in fission of {sup 235}U in the OSIRIS combined target and ion source. The nuclei were studied by standard nuclear spectroscopy measuring techniques: Singles {gamma} spectra and {gamma}{gamma}-coincidence data were obtained. In addition {gamma}{gamma}({theta}) angular correlation and {beta}{gamma}{gamma}(t) triple coincidence ``fast-timing`` ,measurements were performed on the nuclei in the {sup 132}Sn (N=82,Z=50) region. Detailed level schemes for the {sup 84,85}Se, {sup 132}Sb,{sup 132}Sn, {sup 132}Te nuclei were built, greatly improvi our knowledge of the structure of these nuclei. The experimentally deduced transition rates and multipole mixing ratios of the studied {sup 132}Sn region nuclei were compared to theoretical calculations within the random phase approximation framework and related models. Particular attention was paid to the collective properties of nuclei in the {sup 132}Sn region, parametrized by the electrical octupole effective charge. A range of general software spectroscopic tools were developed for the purpose of analysing the experimental data. This included a program, Yggdrasil, which for the first time allowed a complete two-dimensional {gamma}{gamma}-coincidence matrix to be analysed on ordinary ``small`` personal computers (PCs). 49 refs., 10 figs., 2 tabs.

Reflective photovoltaics

Energy Technology Data Exchange (ETDEWEB)

Lentine, Anthony L.; Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Goeke, Ronald S.

2018-03-06

A photovoltaic module includes colorized reflective photovoltaic cells that act as pixels. The colorized reflective photovoltaic cells are arranged so that reflections from the photovoltaic cells or pixels visually combine into an image on the photovoltaic module. The colorized photovoltaic cell or pixel is composed of a set of 100 to 256 base color sub-pixel reflective segments or sub-pixels. The color of each pixel is determined by the combination of base color sub-pixels forming the pixel. As a result, each pixel can have a wide variety of colors using a set of base colors, which are created, from sub-pixel reflective segments having standard film thicknesses.

Closely spaced mirror pair for reshaping and homogenizing pump beams in laser amplifiers

International Nuclear Information System (INIS)

Bass, I.L.

1992-12-01

Channeling a laser beam by multiple reflections between two closely-spaced, parallel or nearly parallel mirrors, serves to reshape and homogenize the beam at the output gap between the mirrors. Application of this device to improve the spatial overlap of a copper laser pump beam with the signal beam in a dye laser amplifier is described. This technique has been applied to the AVLIS program at the Lawrence Livermore National Laboratory

Beyond ‘Innocents Abroad’: Reflecting on Sustainability Issues During International Study Trips

Directory of Open Access Journals (Sweden)

Anne H. Reilly

2016-12-01

Full Text Available With ecosystems and populations in many regions threatened by rapid development, sustainability is a critical component for businesses in mature markets and emerging economies alike. The International Association of Jesuit Business Schools notes that global sustainability involves a broad set of interconnected issues ranging from environmental preservation to social justice to desirable production and consumption patterns. Jesuit business schools are uniquely positioned to address sustainability issues with their focus on teaching managerial content in tandem with corporate social responsibility. Further, the Ignatian Pedagogy Paradigm of experience, reflection, and action would suggest that business students may benefit from reflective observation in support of learning about sustainability. In this paper, we examine the international study trip as an opportunity for students to learn about sustainability, with results suggesting that student understanding about the broad sustainability domain may be enhanced through the study abroad experience. We discuss how two classes of primarily American MBA students traveling to emerging markets (one class to Santiago, Chile and one class to Johannesburg, South Africa were able to connect local business practices with economic and social as well as environmental sustainability issues, enhancing both student engagement and learning outcomes. Further, these students’ sustainability experiences while in an unfamiliar environment provided the opportunity to apply the potentially transformative experience, reflection, and action components of the Ignatian Pedagogy Paradigm. Compared to similar graduate business students enrolled in regular classes, we argue that these students discerned deeper connections with the economic, social, and environmental issues of sustainability.

Effect of end reflections on conversion efficiency of coaxial relativistic backward wave oscillator

Energy Technology Data Exchange (ETDEWEB)

Teng, Yan; Chen, Changhua; Sun, Jun; Shi, Yanchao; Ye, Hu; Wu, Ping; Li, Shuang; Xiong, Xiaolong [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi' an 710024 (China)

2015-11-07

This paper theoretically investigates the effect of end reflections on the operation of the coaxial relativistic backward wave oscillator (CRBWO). It is found that the considerable enhancement of the end reflection at one end increases the conversion efficiency, but excessively large end reflections at both ends weaken the asynchronous wave-beam interaction and thus reduce the conversion efficiency. Perfect reflection at the post end significantly improves the interaction between the electron beam and the asynchronous harmonic so that the conversion efficiency is notably increased. Based on the theoretical research, the diffraction-CRBWO with the generated microwave diffracted and output through the front end of the coaxial slow wave structure cavity is proposed. The post end is conductively closed to provide the perfect reflection. This promotes the amplitude and uniformity of the longitudinal electric field on the beam transmission line and improves the asynchronous wave-beam interaction. In numerical simulations under the diode voltage and current of 450 kV and 5.84 kA, microwave generation with the power of 1.45 GW and the conversion efficiency of 55% are obtained at the frequency of 7.45 GHz.

Pilot Study Comparing Closed Versus Open Tracheal Suctioning in Postoperative Neonates and Infants With Complex Congenital Heart Disease.

Science.gov (United States)

Tume, Lyvonne N; Baines, Paul B; Guerrero, Rafael; Hurley, Margaret A; Johnson, Robert; Kalantre, Atul; Ramaraj, Ram; Ritson, Paul C; Walsh, Laura; Arnold, Philip D

2017-07-01

To determine the hemodynamic effect of tracheal suction method in the first 36 hours after high-risk infant heart surgery on the PICU and to compare open and closed suctioning techniques. Pilot randomized crossover study. Single PICU in United Kingdom. Infants undergoing surgical palliation with Norwood Sano, modified Blalock-Taussig shunt, or pulmonary artery banding in the first 36 hours postoperatively. Infants were randomized to receive open or closed (in-line) tracheal suctioning either for their first or second study tracheal suction in the first 36 hours postoperatively. Twenty-four infants were enrolled over 18 months, 11 after modified Blalock-Taussig shunt, seven after Norwood Sano, and six after pulmonary artery banding. Thirteen patients received the open suction method first followed by the closed suction method second, and 11 patients received the closed suction method first followed by the open suction method second in the first 36 hours after their surgery. There were statistically significant larger changes in heart rate (p = 0.002), systolic blood pressure (p = 0.022), diastolic blood pressure (p = 0.009), mean blood pressure (p = 0.007), and arterial saturation (p = 0.040) using the open suction method, compared with closed suctioning, although none were clinically significant (defined as requiring any intervention). There were no clinically significant differences between closed and open tracheal suction methods; however, there were statistically significant greater changes in some hemodynamic variables with open tracheal suctioning, suggesting that closed technique may be safer in children with more precarious physiology.

On the Radii of Close-in Giant Planets.

Science.gov (United States)

Burrows; Guillot; Hubbard; Marley; Saumon; Lunine; Sudarsky

2000-05-01

The recent discovery that the close-in extrasolar giant planet HD 209458b transits its star has provided a first-of-its-kind measurement of the planet's radius and mass. In addition, there is a provocative detection of the light reflected off of the giant planet tau Bootis b. Including the effects of stellar irradiation, we estimate the general behavior of radius/age trajectories for such planets and interpret the large measured radii of HD 209458b and tau Boo b in that context. We find that HD 209458b must be a hydrogen-rich gas giant. Furthermore, the large radius of a close-in gas giant is not due to the thermal expansion of its atmosphere but to the high residual entropy that remains throughout its bulk by dint of its early proximity to a luminous primary. The large stellar flux does not inflate the planet but retards its otherwise inexorable contraction from a more extended configuration at birth. This implies either that such a planet was formed near its current orbital distance or that it migrated in from larger distances (>/=0.5 AU), no later than a few times 107 yr of birth.

Kinematic Modeling of Normal Voluntary Mandibular Opening and Closing Velocity-Initial Study.

Science.gov (United States)

Gawriołek, Krzysztof; Gawriołek, Maria; Komosa, Marek; Piotrowski, Paweł R; Azer, Shereen S

2015-06-01

Determination and quantification of voluntary mandibular velocity movement has not been a thoroughly studied parameter of masticatory movement. This study attempted to objectively define kinematics of mandibular movement based on numerical (digital) analysis of the relations and interactions of velocity diagram records in healthy female individuals. Using a computerized mandibular scanner (K7 Evaluation Software), 72 diagrams of voluntary mandibular velocity movements (36 for opening, 36 for closing) for women with clinically normal motor and functional activities of the masticatory system were recorded. Multiple measurements were analyzed focusing on the curve for maximum velocity records. For each movement, the loop of temporary velocities was determined. The diagram was then entered into AutoCad calculation software where movement analysis was performed. The real maximum velocity values on opening (Vmax ), closing (V0 ), and average velocity values (Vav ) as well as movement accelerations (a) were recorded. Additionally, functional (A1-A2) and geometric (P1-P4) analysis of loop constituent phases were performed, and the relations between the obtained areas were defined. Velocity means and correlation coefficient values for various velocity phases were calculated. The Wilcoxon test produced the following maximum and average velocity results: Vmax = 394 ± 102, Vav = 222 ± 61 for opening, and Vmax = 409 ± 94, Vav = 225 ± 55 mm/s for closing. Both mandibular movement range and velocity change showed significant variability achieving the highest velocity in P2 phase. Voluntary mandibular velocity presents significant variations between healthy individuals. Maximum velocity is obtained when incisal separation is between 12.8 and 13.5 mm. An improved understanding of the patterns of normal mandibular movements may provide an invaluable diagnostic aid to pathological changes within the masticatory system. © 2014 by the American College of Prosthodontists.

Spectral analysis in overmodulated holographic reflection gratings recorded with BB640 ultrafine grain emulsion

Science.gov (United States)

Mas-Abellán, P.; Madrigal, R.; Fimia, A.

2015-05-01

Silver halide emulsions have been considered one of the most energetic sensitive materials for holographic applications. Nonlinear recording effects on holographic reflection gratings recorded on silver halide emulsions have been studied by different authors obtaining excellent experimental results. In this communication specifically we focused our investigation on the effects of refractive index modulation, trying to get high levels of overmodulation. We studied the influence of the grating thickness on the overmodulation and its effects on the transmission spectra for a wide exposure range by use of two different thickness ultrafine grain emulsion BB640, thin films (6 μm) and thick films (9 μm), exposed to single collimated beams using a red He-Ne laser (wavelength 632.8 nm) with Denisyuk configuration obtaining a spatial frequency of 4990 l/mm recorded on the emulsion. The experimental results show that high overmodulation levels of refractive index could offer some benefits such as high diffraction efficiency (reaching 90 %), increase of grating bandwidth (close to 80 nm), making lighter holograms, or diffraction spectra deformation, transforming the spectrum from sinusoidal to approximation of square shape. Based on these results, we demonstrate that holographic reflection gratings spectra recorded with overmodulation of refractive index is formed by the combination of several non-linear components due to very high overmodulation. This study is the first step to develop a new easy multiplexing technique based on the use of high index modulation reflection gratings.

The motivational hierarchy between the personal self and close others in the Chinese brain: an ERP study

Directory of Open Access Journals (Sweden)

Xiangru Zhu

2016-09-01

Full Text Available People base their decisions not only on their own self-interest but also on the interests of close others. Generally, the personal self has primacy in the motivational hierarchy in the Western culture. A recent study found that friends have the same motivational hierarchy as the personal self in the Eastern collectivist culture. Remaining unknown is whether the motivational hierarchy of the personal self and close others can be manifested in the collectivist brain. In the present study, we asked participants to gamble for the personal self, close others (i.e., mother, father, and close friend, and strangers. The positive-going deflection of event-related potentials (ERPs in response to positive feedback showed the following pattern: personal self = mother = father > friend > stranger. In the loss condition, no significant beneficiary effect was observed. The present results indicate that the personal self and parents are intertwined in the motivational system in the Chinese undergraduate student brain, supporting the view that the personal self and parents have the same motivational primacy at the electrocortical level.

The Motivational Hierarchy between the Personal Self and Close Others in the Chinese Brain: an ERP Study.

Science.gov (United States)

Zhu, Xiangru; Wang, Lili; Yang, Suyong; Gu, Ruolei; Wu, Haiyan; Luo, Yuejia

2016-01-01

People base their decisions not only on their own self-interest but also on the interests of close others. Generally, the personal self has primacy in the motivational hierarchy in the Western culture. A recent study found that friends have the same motivational hierarchy as the personal self in the Eastern collectivist culture. Remaining unknown is whether the motivational hierarchy of the personal self and close others can be manifested in the collectivist brain. In the present study, we asked participants to gamble for the personal self, close others (i.e., mother, father, and close friend), and strangers. The positive-going deflection of event-related potentials (ERPs) in response to positive feedback showed the following pattern: personal self = mother = father > friend > stranger. In the loss condition, no significant beneficiary effect was observed. The present results indicate that the personal self and parents are intertwined in the motivational system in the Chinese undergraduate student brain, supporting the view that the personal self and parents have the same motivational primacy at the electrocortical level.

Family Caregivers' Reflections on Experiences of Assisted Suicide in Switzerland: A Qualitative Interview Study.

Science.gov (United States)

Gamondi, C; Pott, Murielle; Preston, Nancy; Payne, Sheila

2018-04-01

Thousands of family members worldwide are annually involved in assisted dying. Family participation in assisted dying has rarely been investigated and families' needs typically are not considered in assisted dying legislation and clinical guidelines. To explore family caregivers' reflections on experiences of assisted suicide in Switzerland. A cross-sectional qualitative interview study conducted in the Italian- and French-speaking regions of Switzerland. Interpretation and analysis were performed using qualitative content analysis. Twenty-eight close relatives and family carers of 18 patients who died by assisted suicide in Switzerland were interviewed. Family members perceived their involvement in assisted suicide as characterized by five phases; 1) contemplation, 2) gaining acceptance, 3) gaining permission, 4) organization, and 5) aftermath. Families can participate in these phases at diverse levels and with varying degrees of involvement. Important triggers for families and patients for transition between phases include patients' experiences of their life-threatening illnesses and related treatments, their increasing awareness of approaching death, and family member recognition of their loved one's unbearable suffering. Participating in assisted suicide created further demanding tasks for families in addition to their role of caregivers. Families appeared to be involved in the preparation of assisted suicide along with patients, irrespective of their personal values regarding assisted dying. Support for family members is essential if they are involved in tasks preparatory to assisted suicide. Clinical guidelines and policies concerning assisted dying should acknowledge and address family needs. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

The significance of ethics reflection groups in mental health care: a focus group study among health care professionals.

Science.gov (United States)

Hem, Marit Helene; Molewijk, Bert; Gjerberg, Elisabeth; Lillemoen, Lillian; Pedersen, Reidar

2018-06-05

Professionals within the mental health services face many ethical dilemmas and challenging situations regarding the use of coercion. The purpose of this study was to evaluate the significance of participating in systematic ethics reflection groups focusing on ethical challenges related to coercion. In 2013 and 2014, 20 focus group interviews with 127 participants were conducted. The interviews were tape recorded and transcribed verbatim. The analysis is inspired by the concept of 'bricolage' which means our approach was inductive. Most participants report positive experiences with participating in ethics reflection groups: A systematic and well-structured approach to discuss ethical challenges, increased consciousness of formal and informal coercion, a possibility to challenge problematic concepts, attitudes and practices, improved professional competence and confidence, greater trust within the team, more constructive disagreement and room for internal critique, less judgmental reactions and more reasoned approaches, and identification of potential for improvement and alternative courses of action. On several wards, the participation of psychiatrists and psychologists in the reflection groups was missing. The impact of the perceived lack of safety in reflection groups should not be underestimated. Sometimes the method for ethics reflection was utilised in a rigid way. Direct involvement of patients and family was missing. This focus group study indicates the potential of ethics reflection groups to create a moral space in the workplace that promotes critical, reflective and collaborative moral deliberations. Future research, with other designs and methodologies, is needed to further investigate the impact of ethics reflection groups on improving health care practices.

The influence of anisotropic electron drift velocity on the signal shapes of closed-end HPGe detectors

CERN Document Server

Mihailescu, L; Lieder, R M; Brands, H; Jaeger, H

2000-01-01

This study is concerned with the anisotropy of the electron drift velocity in germanium crystals at high electric fields and low temperature, and its influence on the charge collection process in n-type, high-purity germanium (HPGe) detectors of closed-end, coaxial geometry. The electron trajectories inside HPGe detectors are simulated using a phenomenological model to calculate the dependence of the drift velocity on the angle between the electric field and the crystal orientation. The resulting induced currents and pulse shapes for a given detector geometry and preamplifier bandwidth are compared to experiment. Experimentally, the dependence of the pulse shapes on the conductivity anisotropy in closed-end HPGe detectors was observed. The experimental data on pulse shapes were obtained by sampling preamplifier signals of an encapsulated, hexaconical EUROBALL detector, which was irradiated by collimated sup 2 sup 2 Na and sup 2 sup 4 sup 1 Am sources. The crystal orientation was measured by neutron reflection...

Variation of MODIS reflectance and vegetation indices with viewing geometry and soybean development

Directory of Open Access Journals (Sweden)

Fábio M. Breunig

2012-06-01

Full Text Available Directional effects introduce a variability in reflectance and vegetation index determination, especially when large field-of-view sensors are used (e.g., Moderate Resolution Imaging Spectroradiometer - MODIS. In this study, we evaluated directional effects on MODIS reflectance and four vegetation indices (Normalized Difference Vegetation Index - NDVI; Enhanced Vegetation Index - EVI; Normalized Difference Water Index - NDWI1640 and NDWI2120 with the soybean development in two growing seasons (2004-2005 and 2005-2006. To keep the reproductive stage for a given cultivar as a constant factor while varying viewing geometry, pairs of images obtained in close dates and opposite view angles were analyzed. By using a non-parametric statistics with bootstrapping and by normalizing these indices for angular differences among viewing directions, their sensitivities to directional effects were studied. Results showed that the variation in MODIS reflectance between consecutive phenological stages was generally smaller than that resultant from viewing geometry for closed canopies. The contrary was observed for incomplete canopies. The reflectance of the first seven MODIS bands was higher in the backscattering. Except for the EVI, the other vegetation indices had larger values in the forward scattering direction. Directional effects decreased with canopy closure. The NDVI was lesser affected by directional effects than the other indices, presenting the smallest differences between viewing directions for fixed phenological stages.Efeitos direcionais introduzem variabilidade na reflectância e na determinação de índices de vegetação, especialmente quando sensores de amplo campo de visada são usados (p.ex., Moderate Resolution Imaging Spectroradiometer - MODIS. Neste estudo, nós avaliamos os efeitos direcionais sobre a reflectância e quatro índices de vegetação (Normalized Difference Vegetation Index - NDVI; Enhanced Vegetation Index - EVI; Normalized

Modeling the effect of reflection from metallic walls on spectroscopic measurements

International Nuclear Information System (INIS)

Zastrow, K.-D.; Keatings, S. R.; O'Mullane, M. G.; Marot, L.; Temmerman, G. de

2008-01-01

A modification of JET is presently being prepared to bring operational experience with ITER-like first wall (Be) and divertor (W) materials, geometry and plasma parameters. Reflectivity measurements of JET sample tiles have been performed and the data are used within a simplified model of the JET and ITER vessels to predict additional contributions to quantitative spectroscopic measurements. The most general method to characterize reflectivity is the bidirectional reflection distribution function (BRDF). For extended sources however, such as bremsstrahlung and edge emission of fuel and intrinsic impurities, the results obtained in the modeling are almost as accurate if the total reflectivity with ideal Lambertian angular dependence is used. This is in contrast to the experience in other communities, such as optical design, lighting design, or rendering who deal mostly with pointlike light sources. This result is so far based on a very limited set of measurements and will be reassessed when more detailed BRDF measurements of JET tiles have been made. If it is true it offers the possibility of in situ monitoring of the reflectivity of selected parts of the wall during exposure to plasma operation, while remeasurement of the BRDF is performed during interventions. For a closed vessel structure such as ITER, it is important to consider multiple reflections. This makes it more important to represent the whole of the vessel reasonably accurately in the model, which on the other hand is easier to achieve than for the more complex internal structure of JET. In both cases the dominant contribution is from the first reflection, and a detailed model of the areas intersected by lines of sight of diagnostic interest is required.

A closed-loop photon beam control study for the Advanced Light Source

International Nuclear Information System (INIS)

Portmann, G.; Bengtsson, J.

1993-05-01

The third generation Advanced Light Source (ALS) will produce extremely bright photon beams using undulators and wigglers. In order to position the photon beams accurate to the micron level, a closed-loop feedback system is being developed. Using photon position monitors and dipole corrector magnets, a closed-loop system can automatically compensate for modeling uncertainties and exogenous disturbances. The following paper will present a dynamics model for the perturbations of the closed orbit of the electron beam in the ALS storage ring including the vacuum chamber magnetic field penetration effects. Using this reference model, two closed-loop feedback algorithms will be compared -- a classical PI controller and a two degree-of-freedom approach. The two degree-of-freedom method provides superior disturbance rejection while maintaining the desired performance goals. Both methods will address the need to gain schedule the controller due to the time varying dynamics introduced by changing field strengths when scanning the insertion devices

'The Loss of My Elderly Patient:' Interactive reflective writing to support medical students' rites of passage.

Science.gov (United States)

Wald, Hedy S; Reis, Shmuel P; Monroe, Alicia D; Borkan, Jeffrey M

2010-01-01

The fostering of reflective capacity within medical education helps develop critical thinking and clinical reasoning skills and enhances professionalism. Use of reflective narratives to augment reflective practice instruction is well documented. At Warren Alpert Medical School of Brown University (Alpert Med), a narrative medicine curriculum innovation of students' reflective writing (field notes) with individualized feedback from an interdisciplinary faculty team (in pre-clinical years) has been implemented in a Doctoring course to cultivate reflective capacity, empathy, and humanism. Interactive reflective writing (student writer/faculty feedback provider dyad), we propose, can additionally support students with rites of passage at critical educational junctures. At Alpert Med, we have devised a tool to guide faculty in crafting quality feedback, i.e. the Brown Educational Guide to Analysis of Narrative (BEGAN) which includes identifying students' salient quotes, utilizing reflection-inviting questions and close reading, highlighting derived lessons/key concepts, extracting clinical patterns, and providing concrete recommendations as relevant. We provide an example of a student's narrative describing an emotionally powerful and meaningful event - the loss of his first patient - and faculty responses using BEGAN. The provision of quality feedback to students' reflective writing - supported by BEGAN - can facilitate the transformation of student to professional through reflection within medical education.

Closed sets of nonlocal correlations

International Nuclear Information System (INIS)

Allcock, Jonathan; Linden, Noah; Brunner, Nicolas; Popescu, Sandu; Skrzypczyk, Paul; Vertesi, Tamas

2009-01-01

We present a fundamental concept - closed sets of correlations - for studying nonlocal correlations. We argue that sets of correlations corresponding to information-theoretic principles, or more generally to consistent physical theories, must be closed under a natural set of operations. Hence, studying the closure of sets of correlations gives insight into which information-theoretic principles are genuinely different, and which are ultimately equivalent. This concept also has implications for understanding why quantum nonlocality is limited, and for finding constraints on physical theories beyond quantum mechanics.

Moving from technical to critical reflection in journalling: an investigation of students' ability to incorporate three levels of reflective writing.

Science.gov (United States)

Usher, K; Tollefson, J; Francis, D

2001-01-01

This paper outlines a research project aimed at changing the levels of reflection of preregistration nursing students in a tertiary institution. Whilst reflection is widely espoused now in nursing, few studies have been found that identify whether the level of reflective writing can be identified or developed by students. Anecdotal and research evidence (Powell 1989; van Manen 1977) however indicates that most student reflective writing occurs at the technical level. A descriptive exploratory study using both qualitative and quantitative techniques was undertaken to apply van Manen's (1977) levels in a structured way in an attempt to facilitate the student's understanding and use of the levels in their reflective writing. The findings of the study indicate that student self evaluation and identification of the levels in their own writing can lead to change in the levels of critical reflective writing achieved by undergraduate students.

Reflection and Transmission of P-Waves in an Intermediate Layer Lying Between Two Semi-infinite Media

Science.gov (United States)

Singh, Pooja; Chattopadhyay, Amares; Srivastava, Akanksha; Singh, Abhishek Kumar

2018-05-01

With a motivation to gain physical insight of reflection as well as transmission phenomena in frozen (river/ocean) situation for example in Antarctica and other coldest place on Earth, the present article undertakes the analysis of reflection and transmission of a plane wave at the interfaces of layered structured comprised of a water layer of finite thickness sandwiched between an upper half-space constituted of ice and a lower isotropic elastic half-space, which may be useful in geophysical exploration in such conditions. A closed form expression of reflection/transmission coefficients of reflected and transmitted waves has been derived in terms of angles of incidence, propagation vector, displacement vector and elastic constants of the media. Expressions corresponding to the energy partition of various reflected and transmitted waves have also been established analytically. It has been remarkably shown that the law of conservation of energy holds good in the entire reflection and transmission phenomena for different angles of incidence. A numerical examples were performed so to graphically portray the analytical findings. Further the deduced results are validated with the pre-established classical results.

The simplest models of the reflection nebulae

International Nuclear Information System (INIS)

Voshchinnikov, N.V.

1977-01-01

Some models of the reflection nebulue have been considered. The (U-B), (B-V) and (V-R) colors and the U, B, V and R polarization have been calculated for a model of a reflection nebula associated with a large dust cloud. For the cases in which the illuminating star is far from the surface of the cloud, the form of the nebula has been considered to be spherical. If the star is close to the surface of the cloud, a part of the nebura boundary has been considered to be flat. Single scattering within the homogeneous nebula has been assumed. All the calculations use the scattering by spheres as given by the Mie's theory. The effect of variations of chemical composition and size distribution function of the grains and the position of the illuminating star has been examined. Comparison of the theoretical results with the observations of the Merope nebula shows that the dirty ice grains with the refraction index m=1.30-0.02i and size parameter asub(o)=0.5μ represent satisfactorily the observation if the star is embedded 0.7 pc behind the front surface of the nebula

Eliciting and Assessing Reflective Practice: A Case Study in Web 2.0 Technologies

Science.gov (United States)

Parkes, Kelly A.; Kajder, Sara

2010-01-01

This paper focuses on the role of multimodal technologies in facilitating reflective processes and the subsequent assessment of reflectivity for students in pre-professional programs. Reflective practice has been established as a critical tool for developing identity in and on practice. This paper will focus firstly on reviewing salient literature…

Comparative study of reflectance properties of nanodiamonds, onion-like carbon and multiwalled carbon nanotubes

Energy Technology Data Exchange (ETDEWEB)

Kuznetsov, V.L. [Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk (Russian Federation); Moseenkov, S.I. [Boreskov Institute of Catalysis, SB RAS, Lavrentiev Ave. 5, 630090 Novosibirsk (Russian Federation); Nikolaev Institute of Inorganic Chemistry, SB RAS, Lavrentiev Ave. 3, 630090 Novosibirsk (Russian Federation); Elumeeva, K.V. [Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk (Russian Federation); Boreskov Institute of Catalysis, SB RAS, Lavrentiev Ave. 5, 630090 Novosibirsk (Russian Federation); Larina, T.V.; Anufrienko, V.F. [Boreskov Institute of Catalysis, SB RAS, Lavrentiev Ave. 5, 630090 Novosibirsk (Russian Federation); Romanenko, A.I.; Anikeeva, O.B.; Tkachev, E.N. [Novosibirsk State University, Pirogova St. 2, 630090 Novosibirsk (Russian Federation); Nikolaev Institute of Inorganic Chemistry, SB RAS, Lavrentiev Ave. 3, 630090 Novosibirsk (Russian Federation)

2011-11-15

Carbon nanomaterials are the promising candidates for potential broadband limiting applications and extremely low reflectance coatings, particularly in the infrared, visible and UV spectral regions. In this paper we have performed the comparative study of diffuse reflectance of nanodiamond (ND), sp{sup 2}/sp{sup 3} composites, onion-like carbon (OLC) and multiwalled carbon nanotubes (MWNTs) in visible and UV regions. ND, sp{sup 2}/sp{sup 3} composites and OLC produced via high temperature annealing of the same set of NDs allow us to vary sp{sup 2}/sp{sup 3} carbon ratio, size of primary particle agglomerates and concentration of defects while MWNT set provides possibility to vary NT diameters and length, order/disorder degree (via high temperature MWNTS annealing). The diffuse reflectance of carbon nanomaterials depends mainly on the electronic configuration, defect concentration, size of graphene-like ordered fragments and agglomerates of nanoparticles along with their morphology. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Density-based reflectivity in seismic exploration for coal in Alberta, Canada

Energy Technology Data Exchange (ETDEWEB)

Lawton, D.C.; Lyatsky, H.V. (University of Calgary, AB (Canada). Dept. of Geology and Geophysics)

1991-01-01

At a coal field in central Alberta, Canada, the acoustic reflectivity of shallow coal seams was found to be dominated by the density contrast between coal and host bentonitic sediments. Sonic logs and a check-shot survey showed that the compressional-wave velocity is almost constant through the coal zone and the overlying sediments, and ranges in value between 2000 m/s and 2350 m/s over different parts of the coal field. The average coal density is 1400 kg/m{sup 3}, whereas the density of the sediments is about 2200 kg/m{sup 3}. Results are illustrated using logs from a typical drillhole in the coal field. At this location, the time reflectivity sequence based on both the density and sonic logs is very similar to that obtained when the density log only is used, with a constant velocity assumed through the coal zone. At another drillhole location in the coal field, where reflection seismic data had been acquired, a synthetic seismogram generated from the density log closely matches the stacked seismic section. 6 refs., 4 figs.

Attenuated total reflection design for in situ FT-IR spectroelectrochemical studies

International Nuclear Information System (INIS)

Visser, Hendrik; Curtright, Aimee E.; McCusker, James K.; Sauer, Kenneth

2000-01-01

A versatile spectroelectrochemical apparatus is introduced to study the changes in IR spectra of organic and inorganic compounds upon oxidation or reduction. The design is based on an attenuated total reflection (ATR) device, which permits the study of a wide spectral range of 16,700 cm-1 (600 nm) - 250 cm-1 with a small opaque region of 2250 - 1900 cm-1. In addition, an IR data collection protocol is introduced to deal with electrochemically non-reversible background signals. This method is tested with ferrocene in acetonitrile, producing results that agree with those in the literature

Quantifying Reflection

DEFF Research Database (Denmark)

Alcock, Gordon Lindsay

2013-01-01

´ These are all based on Blooms taxonomy and levels of competence and form a major part of individual student and group learning portfolios. Key Words :Project-Based learning, Reflective Portfolios, Self assessment, Defining learning gains, Developing learning strategies , Reflections on and for learning....... It contrasts the students’ self-assessment in a range of ‘product’ skills such as Revit, Structural Design, Mathematics of construction, Technical Installations; as well as ‘process’ competencies such as ‘Working in a team’, Sharing knowledge, Maintaining a portfolio and Reflecting ON learning and FOR learning......This paper documents 1st semester student reflections on “learning to learn” in a team-based PBL environment with quantitative and qualitative student reflective feedback on the learning gains of 60 Architectural Technology and Construction Management students at VIA University College, Denmark...

Reflective journal writing: how it promotes reflective thinking in clinical nursing education: a students' perspective.

Science.gov (United States)

Kok, J; Chabeli, M M

2002-08-01

According to the outcomes-based education and training system of education (OBET) in the country and the South African Nursing Council, education should focus on "creating" reflective learners and practitioners. This article seeks to determine the effectiveness of reflective journal writing in promoting the reflective thinking of learners in clinical nursing education and to validate the guidelines described in a bigger study on how to facilitate reflective thinking using reflective journal writing. A qualitative, contextual, explorative, descriptive research design was used to determine the learners' perceptions on whether reflective journal writing did promote their higher-level thinking skills during the six-month placement in a psychiatric clinical practice using the reflective diaries. From a population of seventeen fourth-year students, six volunteered to participate in a focus group interview. The data was analysed by means of the descriptive method of open coding of Tesch (in Creswell, 1994:154-156). Positive and negative results from the perceptions of the participants and a literature review served as a basis for deducing and describing guidelines for the effective use of reflective journal writing in promoting reflective thinking in clinical nursing education. The positive perception was the development of problem-solving skills attained through reflection by using analytical critical thinking, synthesis and the evaluation of situations. Self-evaluation leading to intellectual growth and self-awareness indicated a positive perception. Negative perceptions were that reflective journal writing is time consuming, content based with a lack of clear expectations from the teacher, and distrust of students about the information written. Guba's model of ensuring trustworthiness in qualitative research as described in Krefting (1991:215-222) was employed. It is concluded that reflective journal writing in clinical nursing education does promote reflective

Blogging for Reflection: The Use of Online Journals to Engage Students in Reflective Learning

Science.gov (United States)

Muncy, James A.

2014-01-01

Reflective learning has long been studied in many disciplines. A primary way that reflective learning has been taught is through journaling. With the advent of e-learning, journaling has moved to the Web in the form of blogs. The current paper reviews the current state of journaling and blogging research with specific recommendations for marketing…

A PROSPECTIVE STUDY OF SUPRACONDYLAR FRACTURES OF THE HUMERUS IN CHILDREN TREATED BY CLOSED REDUCTION

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Ch. Imobi

2015-08-01

Full Text Available There is no universal agreement regarding the management of displaced supracondylar fracture of the humerous in children. According to some orthopaedic surgeon almost all supracondylar humeral fractures should be treated operatively by reduction and pinning. While according to others closed reduction and pinning should be used for Gartland type II and some type III fractures. We present 50 cases of displaced supracondylar fracture treated by closed manipulative reduction under G.A. and immobilization with a posterior plaster of paris slab and collar and cuff. OBJECTIVE : T o assess the functional results of the injured elbow and to study the incidence of change in the carrying angle of the elbow. MATERIALS AND METHODS: This prospective study was conducted in 50 patients with extension type of displaced supracondylar fractures of humerus in children (Gartland type II and type III treated by closed manipulative reduction and immobilization in flexion of the elbow with a posterior plaster of paris slab and collar and cuff. Patients were followed up for 6 months. Flexion type of supracondylar fracture and those fractures which are absolutely indicated for operative intervention, Viz an open fracture and severe vascular compromise were excluded from the study. The range of movement and carrying angle was measured with the help of a Goniometer and Flynn criteria were used for functional assessment. RESULTS: At the end of follow up period, the end results were graded as excellent in 40%, good in 42%, fair in 12% and poor in 6%. A satisfactory result was therefore obtained in 94% and unsatisfactory result in 6% of the 50 patients who were followed and evaluated. CONCLUSION: This closed method of treatment for all practical proposes produces least complications, shorter hospital stay, can be expected to yield reproducible consistent satisfactory results not surpassed by any other method of treatment.

Selectively reflective transparent sheets

Science.gov (United States)

Waché, Rémi; Florescu, Marian; Sweeney, Stephen J.; Clowes, Steven K.

2015-08-01

We investigate the possibility to selectively reflect certain wavelengths while maintaining the optical properties on other spectral ranges. This is of particular interest for transparent materials, which for specific applications may require high reflectivity at pre-determined frequencies. Although there exist currently techniques such as coatings to produce selective reflection, this work focuses on new approaches for mass production of polyethylene sheets which incorporate either additives or surface patterning for selective reflection between 8 to 13 μ m. Typical additives used to produce a greenhouse effect in plastics include particles such as clays, silica or hydroxide materials. However, the absorption of thermal radiation is less efficient than the decrease of emissivity as it can be compared with the inclusion of Lambertian materials. Photonic band gap engineering by the periodic structuring of metamaterials is known in nature for producing the vivid bright colors in certain organisms via strong wavelength-selective reflection. Research to artificially engineer such structures has mainly focused on wavelengths in the visible and near infrared. However few studies to date have been carried out to investigate the properties of metastructures in the mid infrared range even though the patterning of microstructure is easier to achieve. We present preliminary results on the diffuse reflectivity using FDTD simulations and analyze the technical feasibility of these approaches.

Global Explorers Journaling and Reflection Initiative

Directory of Open Access Journals (Sweden)

John Bennion

2016-12-01

Full Text Available Research suggests that journaling will increase reflection and improve program outcomes (Bain, et al, 1999; Duerden, et al, 2012 This study involved a partnership with a non-profit, Global Explorers (GEx, which provides international immersion experiences for youth. Their programs are designed to teach youth participants principles of leadership, environmental awareness, service, and science. This study, which tested whether teaching journaling techniques to youth program facilitators would have a positive impact on participant outcomes, addressed the following hypotheses: 1 Greater training in reflective thinking among participants would be associated with higher outcome scores, and 2 Participants in the intervention group (facilitators trained in journaling pedagogy would show greater increases in reflective thinking than comparison group members. Results based on participant self-assessment were significant in testing the first hypothesis; reflective thinking is positively associated with outcome measures, but the intervention group did not show increases in reflective thinking.

Validating the Persian Version of Reflective Thinking Questionnaire and Probing Iranian University Students' Reflective Thinking and Academic Achievement

Science.gov (United States)

Ghanizadeh, Afsaneh; Jahedizadeh, Safoura

2017-01-01

Scholars in higher education deem reflective thinking as integral to the development of professional disciplinary practices. One of the major issues in studying reflective thinking pivots around its conceptualization and assessment. Over the years, researchers have used several methods and scales to measure reflective thinking. One of the most…

Theory of reflection reflection and transmission of electromagnetic, particle and acoustic waves

CERN Document Server

Lekner, John

2016-01-01

This book deals with the reflection of electromagnetic and particle waves by interfaces. The interfaces can be sharp or diffuse. The topics of the book contain absorption, inverse problems, anisotropy, pulses and finite beams, rough surfaces, matrix methods, numerical methods,  reflection of particle waves and neutron reflection. Exact general results are presented, followed by long wave reflection, variational theory, reflection amplitude equations of the Riccati type, and reflection of short waves. The Second Edition of the Theory of Reflection is an updated and much enlarged revision of the 1987 monograph. There are new chapters on periodically stratified media, ellipsometry, chiral media, neutron reflection and reflection of acoustic waves. The chapter on anisotropy is much extended, with a complete treatment of the reflection and transmission properties of arbitrarily oriented uniaxial crystals. The book gives a systematic and unified treatment reflection and transmission of electromagnetic and particle...

Using Mobile Learning to Improve the Reflection: A Case Study of Traffic Violation

Science.gov (United States)

Lan, Yu-Feng; Huang, Shin-Ming

2012-01-01

The purpose of this study was to integrate mobile communication technologies and a global positioning system (GPS) to construct an instant, convenient report of the mobile network service system named the Mobile Traffic Violation Reporting System (MTVRS), to improve learners' traffic violation reflection level. Data were collected using a…

Reflection Negative Kernels and Fractional Brownian Motion

Directory of Open Access Journals (Sweden)

Palle E. T. Jorgensen

2018-06-01

Full Text Available In this article we study the connection of fractional Brownian motion, representation theory and reflection positivity in quantum physics. We introduce and study reflection positivity for affine isometric actions of a Lie group on a Hilbert space E and show in particular that fractional Brownian motion for Hurst index 0 < H ≤ 1 / 2 is reflection positive and leads via reflection positivity to an infinite dimensional Hilbert space if 0 < H < 1 / 2 . We also study projective invariance of fractional Brownian motion and relate this to the complementary series representations of GL 2 ( R . We relate this to a measure preserving action on a Gaussian L 2 -Hilbert space L 2 ( E .

Written reflection in an eHealth intervention for adults with type 2 diabetes mellitus: a qualitative study.

Science.gov (United States)

Lie, Silje S; Karlsen, Bjørg; Niemiec, Christopher P; Graue, Marit; Oftedal, Bjørg

2018-01-01

Individuals with type 2 diabetes mellitus (T2DM) are responsible for the daily decisions and actions necessary to manage their disease, which makes self-management the cornerstone of diabetes care. Many patients do not reach recommended treatment goals, and thus it is important to develop and evaluate innovative interventions that facilitate optimal motivation for adequate self-management of T2DM. The aim of the current study was to explore how adults with T2DM experience using reflection sheets to stimulate written reflection in the context of the Guided Self-Determination (GSD) eHealth intervention and how written reflection might affect their motivation for self-management of T2DM. We used a qualitative design in which data were collected through individual interviews. The sample consisted of 10 patients who completed the GSD eHealth intervention, and data were analyzed using qualitative content analysis. The qualitative content analysis yielded 2 main themes. We labeled the first theme as "Written reflection affects awareness and commitment in diabetes self-management", which reflects 2 subthemes, namely, "Writing creates space and time for autonomous reflection" and "Writing influences individuals' focus in diabetes self-management". We labeled the second theme as "Written reflection is perceived as inapplicable in diabetes self-management", which reflects 2 subthemes, namely, "Responding in writing is difficult" and "The timing of the writing is inappropriate". Our findings indicate that written reflection in the context of the GSD eHealth intervention may be conducive to motivation for diabetes self-management for some patients. However, it seems that in-person consultation with the diabetes nurse may be necessary to achieve the full potential benefit of the GSD as an eHealth intervention. We advocate further development and examination of the GSD as a "blended" approach, especially for those who consider written reflection to be difficult or unfamiliar.

Relationship of Dyadic Closeness with Work-Related Stress: A Daily Diary Study

Science.gov (United States)

Lavee, Yoav; Ben-Ari, Adital

2007-01-01

We examined the association between work-related stress of both spouses and daily fluctuations in their affective states and dyadic closeness. Daily diary data from 169 Israeli dual-earner couples were analyzed using multilevel modeling. The findings indicate that work stress has no direct effect on dyadic closeness but rather is mediated by the…

An algorithm to calculate secondary sputtering by the reflection of ions in two dimensions

International Nuclear Information System (INIS)

Smith, R.; Tagg, M.A.

1986-01-01

A method for computing the secondary sputtering of ions reflected from two-dimensional surfaces is described. The surface contour is first approximated by a set of line segments and the displacement of these line segments under ion erosion is determined computationally, by summing the contributions of the primary and reflected fluxes. This method can be used as an alternative to the method of characteristics which is normally used to determine primary ion beam effects. Some simple examples are evaluated. These examples illustrate that primary surface erosion theory is not in itself sufficient to explain the topography which can exist on an ion-eroded surface, particularly close to steep-sided structures. (author)

Making the implicit explicit: environmental teacher as a "reflective practitioner"

Science.gov (United States)

Faria, Cláudia

2015-06-01

This forum article consists on a commentary on the article by Alandeom W. Oliveira, Patterson Rogers, Cassie F. Quigley, Denis Samburskiy, Kimberly Barss and Seema Rivera. The authors emphasized the need for environmental teachers to expand the focus of their instructional efforts beyond rational argumentation and reasoning, taking into account the complex emotional aspects of the human relationship with nature. In this commentary, I attempt to extend the conversation regarding these issues to the need for teachers to be aware about their own environmental beliefs, which could be guiding their teaching. I close with a consideration for the need for environmental teachers to be reflective practitioners, using reflection upon the ends of education, their environmental values and ideas and the moral and ethical aspects of teaching, for challenging students' beliefs and empowering them to make informed environmental decisions, contributing thereby to the building of more just and environmental sustained societies.

Ethical Reflections on Becoming Teachers

Science.gov (United States)

Joseph, Pamela Bolotin

2016-01-01

This study analyzes narratives written in a culminating graduate seminar on reflective practice by 36 new secondary teachers who were asked to consider their moral beliefs, moral values and system of ethics as they reflected on their recent student teaching experiences. The findings explore how the participants depicted their constructed moral…

Specific Features of Reflection of Information Regarding Lease Operations in the National and International Standards

Directory of Open Access Journals (Sweden)

Nikolenko Nataliya V.

2013-12-01

Full Text Available The article identifies the degree of correspondence of the national Provisions (Standard of Business Accounting (PSBA Lease with the international standard and provides recommendations with respect to their closing up. On the results of the study the author provides specific features of international and national standards – the existing IFRS 17 Lease and national PSBA 14 Lease by the following components: definition of lease, its classification and reflection in accounting. Also the text of PSBA 31 Financial Expenditures is supplemented with provisions on capitalisation of financial expenditures prospectively, which would allow avoidance of correction of the balance of the retained income and provision of comparative information for previous periods. The article provides an algorithm of division of lease for accounting purposes on the basis of international standards. Its use would ensure correctness of reflection of lease operations in accounting and would serve as a basis for development of methodical provisions with respect to accounting. By the result of the study the author forms definition of the qualification asset as an asset which requires considerable time for its creation, preparation for target use, sales or acquisition of the ownership right. Capitalisation of such expenditures would allow non-reduction of the accounting income and also would provide a possibility to reflect financial expenditures in accordance with their economic essence.

'Combined reflectance stratigraphy' - subdivision of loess successions by diffuse reflectance spectrometry (DRS)

Science.gov (United States)

Szeberényi, Jozsef; Bradak-Hayashi, Balázs; Kiss, Klaudia; Kovács, József; Varga, György; Balázs, Réka; Szalai, Zoltán; Viczián, István

2016-04-01

The different varieties of loess (and intercalated paleosol layers) together constitute one of the most widespread terrestrial sediments, which was deposited, altered, and redeposited in the course of the changing climatic conditions of the Pleistocene. To reveal more information about Pleistocene climate cycles and/or environments the detailed lithostratigraphical subdivision and classification of the loess variations and paleosols are necessary. Beside the numerous method such as various field measurements, semi-quantitative tests and laboratory investigations, diffuse reflectance spectroscopy (DRS) is one of the well applied method on loess/paleosol sequences. Generally, DRS has been used to separate the detrital and pedogenic mineral component of the loess sections by the hematite/goethite ratio. DRS also has been applied as a joint method of various environmental magnetic investigations such as magnetic susceptibility- and isothermal remanent magnetization measurements. In our study the so-called "combined reflectance stratigraphy method" were developed. At First, complex mathematical method was applied to compare the results of the spectral reflectance measurements. One of the most preferred multivariate methods is cluster analysis. Its scope is to group and compare the loess variations and paleosol based on the similarity and common properties of their reflectance curves. In the Second, beside the basic subdivision of the profiles by the different reflectance curves of the layers, the most characteristic wavelength section of the reflectance curve was determined. This sections played the most important role during the classification of the different materials of the section. The reflectance value of individual samples, belonged to the characteristic wavelength were depicted in the function of depth and well correlated with other proxies like grain size distribution and magnetic susceptibility data. The results of the correlation showed the significance of

Reflecting on reflection in interprofessional education: implications for theory and practice.

Science.gov (United States)

Clark, Phillip G

2009-05-01

Interprofessional education (IPE) involves learning, and learning requires reflection. Educators need to "reflect more on reflection" if they are to be effective teachers in ensuring the learning outcomes essential for teamwork and interprofessional practice (IPP), including incorporating both theory and practice into the development of educational interventions. First, this discussion surveys the IPE-relevant literature on reflection, and then defines and refines the multidimensional concept of reflection as it relates to IPE in developing and implementing teamwork learning programs and experiences. Second, specific methods to promote reflection are presented and explored, including self-assessments, journaling, and written papers. Actual samples from student journals and assignments provide examples of the impacts of using these methods on participant reflection and learning. Finally, implications for an expanded understanding and application of reflection for IPE will be discussed, and recommendations made for educational practice and research in this area.

Substrate Binding Drives Active-Site Closing of Human Blood Group B Galactosyltransferase as Revealed by Hot-Spot Labeling and NMR Spectroscopy Experiments.

Science.gov (United States)

Weissbach, Sophie; Flügge, Friedemann; Peters, Thomas

2018-05-04

Crystallography has shown that human blood group A (GTA) and B (GTB) glycosyltransferases undergo transitions between "open", "semiclosed", and "closed" conformations upon substrate binding. However, the timescales of the corresponding conformational reorientations are unknown. Crystal structures show that the Trp and Met residues are located at "conformational hot spots" of the enzymes. Therefore, we utilized 15 N side-chain labeling of Trp residues and 13 C-methyl labeling of Met residues to study substrate-induced conformational transitions of GTB. Chemical-shift perturbations (CSPs) of Met and Trp residues in direct contact with substrate ligands reflect binding kinetics, whereas the CSPs of Met and Trp residues at remote sites reflect conformational changes of the enzyme upon substrate binding. Acceptor binding is fast on the chemical-shift timescale with rather small CSPs in the range of less than approximately 20 Hz. Donor binding matches the intermediate exchange regime to yield an estimate for exchange rate constants of approximately 200-300 Hz. Donor or acceptor binding to GTB saturated with acceptor or donor substrate, respectively, is slow (<10 Hz), as are coupled protein motions, reflecting mutual allosteric control of donor and acceptor binding. Remote CSPs suggest that substrate binding drives the enzyme into the closed state required for catalysis. These findings should contribute to better understanding of the mechanism of glycosyl transfer of GTA and GTB. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Superconvergent sum rules for the normal reflectivity

International Nuclear Information System (INIS)

Furuya, K.; Zimerman, A.H.; Villani, A.

1976-05-01

Families of superconvergent relations for the normal reflectivity function are written. Sum rules connecting the difference of phases of the reflectivities of two materials are also considered. Finally superconvergence relations and sum rules for magneto-reflectivity in the Faraday and Voigt regimes are also studied

Normal Reflection Characteristics of One-Dimensional Unsteady Flow Shock Waves on Rigid Walls from Pulse Discharge in Water

Directory of Open Access Journals (Sweden)

Dong Yan

2017-01-01

Full Text Available Strong shock waves can be generated by pulse discharge in water, and the characteristics due to the shock wave normal reflection from rigid walls have important significance to many fields, such as industrial production and defense construction. This paper investigates the effects of hydrostatic pressures and perturbation of wave source (i.e., charging voltage on normal reflection of one-dimensional unsteady flow shock waves. Basic properties of the incidence and reflection waves were analyzed theoretically and experimentally to identify the reflection mechanisms and hence the influencing factors and characteristics. The results indicated that increased perturbation (i.e., charging voltage leads to increased peak pressure and velocity of the reflected shock wave, whereas increased hydrostatic pressure obviously inhibited superposition of the reflection waves close to the rigid wall. The perturbation of wave source influence on the reflected wave was much lower than that on the incident wave, while the hydrostatic pressure obviously affected both incident and reflection waves. The reflection wave from the rigid wall in water exhibited the characteristics of a weak shock wave, and with increased hydrostatic pressure, these weak shock wave characteristics became more obvious.

How is Change in Physical Health Status Reflected by Reports of Nurses and Older People Themselves?

DEFF Research Database (Denmark)

Puvill, Thomas; Lindenberg, Jolanda; Slaets, Joris P. J.

2017-01-01

BACKGROUND: Self-rated health is assumed to closely reflect actual health status, but older people's shifting norms and values may influence this association. We investigated how older people's change in self-ratings, in comparison to their retrospective appreciation and change in nurse ratings......, reflect functional decline and mortality risk. METHODS: A representative sample of 85-year olds from a middle-sized city in the Netherlands, excluding those with severe cognitive dysfunction, was followed for 6 years. Participants and a research nurse annually provided ratings of health, and participants...... retrospectively appreciated their annual change in health. Functional status was assessed with the Groningen Activity Rating Scale and all were followed for vital status. RESULTS: Functional decline was reflected by all reports of change in health (all p nurse...

Novel intron markers to study the phylogeny of closely related mammalian species

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Castresana Jose

2010-11-01

Full Text Available Abstract Background Multilocus phylogenies can be used to infer the species tree of a group of closely related species. In species trees, the nodes represent the actual separation between species, thus providing essential information about their evolutionary history. In addition, multilocus phylogenies can help in analyses of species delimitation, gene flow and genetic differentiation within species. However, few adequate markers are available for such studies. Results In order to develop nuclear markers that can be useful in multilocus studies of mammals, we analyzed the mammalian genomes of human, chimpanzee, macaque, dog and cow. Rodents were excluded due to their unusual genomic features. Introns were extracted from the mammalian genomes because of their greater genetic variability and ease of amplification from the flanking exons. To an initial set of more than 10,000 one-to-one orthologous introns we applied several filters to select introns that belong to single-copy genes, show neutral evolutionary rates and have an adequate length for their amplification. This analysis led to a final list of 224 intron markers randomly distributed along the genome. To experimentally test their validity, we amplified twelve of these introns in a panel of six mammalian species. The result was that seven of these introns gave rise to a PCR band of the expected size in all species. In addition, we sequenced these bands and analyzed the accumulation of substitutions in these introns in five pairs of closely related species. The results showed that the estimated genetic distances in the five species pairs was quite variable among introns and that this divergence cannot be directly predicted from the overall intron divergence in mammals. Conclusions We have designed a new set of 224 nuclear introns with optimal features for the phylogeny of closely related mammalian species. A large proportion of the introns tested experimentally showed a perfect amplification

Preliminary closed Brayton cycle study for a space reactor application

International Nuclear Information System (INIS)

Guimaraes, Lamartine Nogueira Frutuoso; Carvalho, Ricardo Pinto de; Camillo, Giannino Ponchio

2007-01-01

The Nuclear Energy Division (ENU) of the Institute for Advanced Studies (IEAv) has started a preliminary design study for a Closed Brayton Cycle Loop (CBCL) aimed at a space reactor application. The main objectives of the study are to establish a starting concept for the CBCL components specifications, and to develop a demonstrative simulator of CBCL in nominal operation conditions. The ENU/IEAv preliminary design study is developing the CBCL around the NOELLE 60290 turbo machine. The actual nuclear reactor study is being conducted independently. Because of that, a conventional heat source is being used for the CBCL, in this preliminary design phase. This paper describes the steady state simulator of the CBCL operating with NOELLE 60290 turbo machine. In principle, several gases are being considered as working fluid, as for instance: air, helium, nitrogen, CO2 and gas mixtures such as helium and xenon. At this moment the simulator is running with Helium as the working fluid. Simplified models of heat and mass transfer are being developed to simulate thermal components. Future efforts will focus on keeping track of the modifications being implemented at the NOELLE 60290 turbo machine in order to build the CBCL. (author)

Preliminary closed Brayton cycle study for a space reactor application

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, Lamartine Nogueira Frutuoso; Carvalho, Ricardo Pinto de [Institute for Advanced Studies, Sao Jose dos Campos, SP (Brazil)]. E-mail: guimarae@ieav.cta.br; Camillo, Giannino Ponchio [Instituto Tecnologico de Aeronautica (ITA), Sao Jose dos Campos, SP (Brazil)]. E-mail: gianninocamillo@gmail.com

2007-07-01

The Nuclear Energy Division (ENU) of the Institute for Advanced Studies (IEAv) has started a preliminary design study for a Closed Brayton Cycle Loop (CBCL) aimed at a space reactor application. The main objectives of the study are to establish a starting concept for the CBCL components specifications, and to develop a demonstrative simulator of CBCL in nominal operation conditions. The ENU/IEAv preliminary design study is developing the CBCL around the NOELLE 60290 turbo machine. The actual nuclear reactor study is being conducted independently. Because of that, a conventional heat source is being used for the CBCL, in this preliminary design phase. This paper describes the steady state simulator of the CBCL operating with NOELLE 60290 turbo machine. In principle, several gases are being considered as working fluid, as for instance: air, helium, nitrogen, CO2 and gas mixtures such as helium and xenon. At this moment the simulator is running with Helium as the working fluid. Simplified models of heat and mass transfer are being developed to simulate thermal components. Future efforts will focus on keeping track of the modifications being implemented at the NOELLE 60290 turbo machine in order to build the CBCL. (author)

Positive Stress and Reflective Practice Among Entrepreneurs

Directory of Open Access Journals (Sweden)

Kati Tikkamäki

2016-01-01

Full Text Available While heavy stress loads seem an unavoidable aspect of entrepreneurship, the positive side of stress (often referred to as ‘eustress’ remains a neglected area of research. This paper contributes to entrepreneurship research by linking the research streams of eustress and reflective practice. As a tool for analysing and developing thoughts and actions, reflective practice plays an important role in the interpretative work essential to positive stress experiences. Following an overview of approaches to stress at work, eustress and reflective practice, the paper explores how entrepreneurs experience the role of positive stress and reflective practice in their work and describes the reflective tools utilized by entrepreneurs in promoting eustress. The research process was designed to support reflective dialogue among the 21 Finnish entrepreneurs from different fields who participated in the study, with results based mainly on qualitative interviews. Nine of the interviewed entrepreneurs also kept a positive stress diary, including a three-day physiological measurement analysing their heartbeat variability. The findings suggest that positive stress and reflective practice are intertwined in the experiences of entrepreneurs and illustrate the role of reflective practice as a crucial toolset for promoting positive stress, comprising six reflective tools: studying oneself, changing one’s point of view, putting things into perspective, harnessing a feeling of trust, regulating resources and engaging in dialogue. Individual reflective capabilities vary, and a theory-driven division of reflective practice into individual, social and contextual dimensions is considered useful in understanding those differences. The research offers a starting point for exploring how eustress and reflective practice affect the well-being of entrepreneurs

Companies closely concerned with the mining industry have a training requirement

International Nuclear Information System (INIS)

Grossekemper, H.J.; Schmidt, B.; Schulenberg, F.

1994-01-01

In view of the serious economic situation the future decisions are extremely difficult for some companies closely concerned with the mining industry. The required orientation of the company towards new markets and new products requires not less, but more training and rethinking in all company divisions: from business management via personnel management to plant organisation and from marketing via development to quality assurance. This is proved by practical examples. An analysis by the ''Training'' working group has produced valuable information on the actual training requirement in the North Rhine-Westphalian engineering industry. It has worked out the concrete situation of the companies closely concerned with the mining industry in North Rhine-Westphalia from the point of view of their own training requirements. It is now the task of each individual company to analyse and reflect its concrete situation against the mirror of the results and to base the specific training requirement on the company aim. (orig.)

Reflection in Learning through a Self-monitoring Device: Design Research on EEG Self-Monitoring during a Study Session

Directory of Open Access Journals (Sweden)

Eva Durall

2017-04-01

Full Text Available The increasing availability of self-monitoring technologies has created opportunities for gaining awareness about one’s own behavior and reflecting on it. In teaching and learning, there is interest in using self-monitoring technologies, but very few studies have explored the possibilities. In this paper, we present a design study that investigates a technology (called Feeler that guides students to follow a specific learning script, monitors changes in their electroencephalogram (EEG while studying, and later provides visualization of the EEG data. The results are two-fold: (1 the hardware/software prototype and (2 the conclusions from the proof-of-concept research conducted with the prototype and six participants. In the research, we collected qualitative data from interviews to identify whether the prototype supported students to develop their reflective skills. The thematic analysis of the interviews showed that the Feeler’s learning script and visualization of the EEG data supported greater levels of reflection by fostering students’ curiosity, puzzlement, and personal inquiry. The proof-of-concept research also provided insights into several factors, such as the value of personal experience, the challenge of assumptions, and the contextualization of the data that trigger reflective thinking. The results validate the design concept and the role of the prototype in supporting awareness of and reflection about students’ mental states when they perform academic tasks.

Dose distribution close to metal implants in Gamma Knife Radiosurgery: A Monte Carlo study

International Nuclear Information System (INIS)

Cheung, Joel Y.C.; Yu, K.N.; Chan, Josie F.K.; Ho, Robert T.K.; Yu, C.P.

2003-01-01

Materials with high atomic numbers favor the occurrence of the photoelectric effect when they are irradiated with gamma rays. Therefore, the photoelectric effects of metal implants within the target regions in Gamma Knife Radiosurgery are worth studying. In the present work, Monte Carlo simulations using EGS4 were employed to investigate the resulting dose enhancements. A dose enhancement as high as 10% was observed close to a platinum implant along the x and y axes, while no significant dose enhancements were observed for silver, stainless steel 301, and titanium ones. A dose enhancement as high as 20% was observed close to the platinum implant along the z axis at the superior position of the metal-phantom interface and was 10% higher for other metal implants

CLOSED-FIELD CORONAL HEATING DRIVEN BY WAVE TURBULENCE

Energy Technology Data Exchange (ETDEWEB)

Downs, Cooper; Lionello, Roberto; Mikić, Zoran; Linker, Jon A [Predictive Science Incorporated, 9990 Mesa Rim Rd. Suite 170, San Diego, CA 92121 (United States); Velli, Marco, E-mail: cdowns@predsci.com [EPSS, UCLA, Los Angeles, CA 90095 (United States)

2016-12-01

To simulate the energy balance of coronal plasmas on macroscopic scales, we often require the specification of the coronal heating mechanism in some functional form. To go beyond empirical formulations and to build a more physically motivated heating function, we investigate the wave-turbulence-driven (WTD) phenomenology for the heating of closed coronal loops. Our implementation is designed to capture the large-scale propagation, reflection, and dissipation of wave turbulence along a loop. The parameter space of this model is explored by solving the coupled WTD and hydrodynamic evolution in 1D for an idealized loop. The relevance to a range of solar conditions is also established by computing solutions for over one hundred loops extracted from a realistic 3D coronal field. Due to the implicit dependence of the WTD heating model on loop geometry and plasma properties along the loop and at the footpoints, we find that this model can significantly reduce the number of free parameters when compared to traditional empirical heating models, and still robustly describe a broad range of quiet-Sun and active region conditions. The importance of the self-reflection term in producing relatively short heating scale heights and thermal nonequilibrium cycles is also discussed.

Density determination of langmuir-blodgett monolayer films using x-ray reflectivity technique

International Nuclear Information System (INIS)

Damar Yoga Kusuma

2015-01-01

Monolayer deposition by Langmuir-Blodgett technique produces monolayer films that are uniform with controllable thickness down to nanometer scale. To evaluate the quality of the monolayer deposition, X-ray reflectivity technique are employed to monitor the monolayers density. Langmuir-Blodgett monolayer with good coverage and uniformity results in film density close to its macroscopic film counterpart whereas films with presence of air gaps shows lower density compared to its macroscopic film counterpart. (author)

Retrieval of reflections from ambient noise using illumination diagnosis

Science.gov (United States)

Vidal, C. Almagro; Draganov, D.; van der Neut, J.; Drijkoningen, G.; Wapenaar, K.

2014-09-01

Seismic interferometry (SI) enables the retrieval of virtual sources at the location of receivers. In the case of passive SI, no active sources are used for the retrieval of the reflection response of the subsurface, but ambient-noise recordings only. The resulting retrieved response is determined by the illumination characteristics of the recorded ambient noise. Characteristics like geometrical distribution and signature of the noise sources, together with the complexity of the medium and the length of the noise records, determine the quality of the retrieved virtual-shot events. To retrieve body wave reflections, one needs to correlate body-wave noise. A source of such noise might be regional seismicity. In regions with notable human presence, the dominant noise sources are generally located at or close to the surface. In the latter case, the noise will be dominated by surface waves and consequently also the retrieved virtual common-source panels will contain dominant retrieved surface waves, drowning out possible retrieved reflections. In order to retrieve reflection events, suppression of the surface waves becomes the most important pre-processing goal. Because of the reasons mentioned above, we propose a fast method to evaluate the illumination characteristics of ambient noise using the correlation results from ambient-noise records. The method is based on the analysis of the so-called source function of the retrieved virtual-shot panel, and evaluates the apparent slowness of arrivals in the correlation results that pass through the position of the virtual source and at zero time. The results of the diagnosis are used to suppress the retrieval of surface waves and therefore to improve the quality of the retrieved reflection response. We explain the approach using modelled data from transient and continuous noise sources and an example from a passive field data set recorded at Annerveen, Northern Netherlands.

Fast vigilance decrement in closed head injury patients as reflected by the mismatch negativity (MMN).

Science.gov (United States)

Kaipio, M L; Novitski, N; Tervaniemi, M; Alho, K; Ohman, J; Salonen, O; Näätänen, R

2001-05-25

Event-related potentials (ERPs) were measured from 24 chronic closed head injury (CHI) patients and 18 age- and education-matched controls. The oddball paradigm was applied while subjects were watching a silent movie. The standard (p=0.8) sound of 75 ms duration had a basic frequency of 500 Hz with harmonic partials of 1000 Hz and 1500 Hz, whereas these frequencies for the pitch deviant were each 10% higher. The frequencies of the duration deviant matched with those of the standard but was 25 ms in duration. The MMN (mismatch negativity), generated by the brain's automatic auditory change-detector mechanism, was elicited by both deviants. No significant differences in the MMN latency or amplitude for either pitch or duration deviants were found between the groups. However, the MMN amplitude for the pitch deviant decreased in the patient group during the experiment considerably faster than in controls, suggesting a faster vigilance decrement in the patients.

Foam application from a closed system – a study of machine and foam parameters

NARCIS (Netherlands)

Lemmen, Jacques T.E.; Groot Wassink, Jan

1990-01-01

An attempt has been made to gain a greater insight into the interaction between foam and a moving textile substrate. The effects of changing wet pick–up, fabric velocity, liquid viscosity, foam density and mode of application on penetration have been studied. Application from a closed system makes

Microplate-compatible total internal reflection fluorescence microscopy for receptor pharmacology

Science.gov (United States)

Chen, Minghan; Zaytseva, Natalya V.; Wu, Qi; Li, Min; Fang, Ye

2013-05-01

We report the use of total internal reflection fluorescence (TIRF) microscopy for analyzing receptor pharmacology and the development of a microplate-compatible TIRF imaging system. Using stably expressed green fluorescence protein tagged β2-adrenergic receptor as the reporter, we found that the activation of different receptors results in distinct kinetic signatures of the TIRF intensity of cells. These TIRF signatures closely resemble the characteristics of their respective label-free dynamic mass redistribution signals in the same cells. This suggests that TIRF in microplate can be used for profiling and screening drugs.

X-ray reflectivity study of thermal capillary waves on liquid surfaces

International Nuclear Information System (INIS)

Ocko, B.M.; Wu, X.Z.; Sirota, E.B.; Sinha, S.K.; Deutsch, M.

1994-01-01

X-ray reflectivity measurements have been carried out at the liquid/vapor interface of normal alkanes. The reflectivities over a large temperature range of different chain lengths (C20 and C36) provide a critical test of the various capillary wave models. Our data are most consistent with the hybrid model which allows for a molecular size dependent cutoff q max for the capillary waves and an intrinsic interface width σ 0

Reflective Practice in the Clinical Setting: A Multi-Institutional Qualitative Study of Pediatric Faculty and Residents.

Science.gov (United States)

Plant, Jennifer; Li, Su-Ting T; Blankenburg, Rebecca; Bogetz, Alyssa L; Long, Michele; Butani, Lavjay

2017-11-01

To explore when and in what form pediatric faculty and residents practice reflection. From February to June 2015, the authors conducted focus groups of pediatric faculty and residents at the University of California, Davis; Stanford University; and the University of California, San Francisco, until thematic saturation occurred. Transcripts were analyzed based on Mezirow's and Schon's models of reflection, using the constant comparative method associated with grounded theory. Two investigators independently coded transcripts and reconciled codes to develop themes. All investigators reviewed the codes and developed a final list of themes through consensus. Through iterative discussions, investigators developed a conceptual model of reflection in the clinical setting. Seventeen faculty and 20 residents from three institutions participated in six focus groups. Five themes emerged: triggers of reflection, intrinsic factors, extrinsic factors, timing, and outcome of reflection. Various triggers led to reflection; whether a specific trigger led to reflection depended on intrinsic and extrinsic factors. When reflection occurred, it happened in action or on action. Under optimal conditions, this reflection was goal and action directed and became critical reflection. In other instances, this process resulted in unproductive rumination or acted as an emotional release or supportive therapy. Participants reflected in clinical settings, but did not always explicitly identify it as reflection or reflect in growth-promoting ways. Strategies to enhance critical reflection include developing knowledge and skills in reflection, providing performance data to inform reflection, creating time and space for safe reflection, and providing mentorship to guide the process.

Reflective masks for extreme ultraviolet lithography

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Khanh Bao [Univ. of California, Berkeley, CA (United States)

1994-05-01

Extreme ultraviolet lithographic masks are made by patterning multilayer reflective coatings with high normal incidence reflectivity. Masks can be patterned by depositing a patterned absorber layer above the coating or by etching the pattern directly into the coating itself. Electromagnetic simulations showed that absorber-overlayer masks have superior imaging characteristics over etched masks (less sensitive to incident angles and pattern profiles). In an EUVL absorber overlayer mask, defects can occur in the mask substrate, reflective coating, and absorber pattern. Electromagnetic simulations showed that substrate defects cause the most severe image degradation. A printability study of substrate defects for absorber overlayer masks showed that printability of 25 nm high substrate defects are comparable to defects in optical lithography. Simulations also indicated that the manner in which the defects are covered by multilayer reflective coatings can affect printability. Coverage profiles that result in large lateral spreading of defect geometries amplify the printability of the defects by increasing their effective sizes. Coverage profiles of Mo/Si coatings deposited above defects were studied by atomic force microscopy and TEM. Results showed that lateral spread of defect geometry is proportional to height. Undercut at defect also increases the lateral spread. Reductions in defect heights were observed for 0.15 μm wide defect lines. A long-term study of Mo/Si coating reflectivity revealed that Mo/Si coatings with Mo as the top layer suffer significant reductions in reflectivity over time due to oxidation.

Which characteristics of written feedback are perceived as stimulating students' reflective competence : an exploratory study

NARCIS (Netherlands)

Dekker, Hanke; Schonrock-Adema, Johanna; Snoek, Jos W.; van der Molen, Thys; Cohen-Schotanus, Janke

2013-01-01

Background: Teacher feedback on student reflective writing is recommended to improve learners' reflective competence. To be able to improve teacher feedback on reflective writing, it is essential to gain insight into which characteristics of written feedback stimulate students' reflection processes.

Studying Corporality in the Gym: Practical Reflections for the Social Sciences

Directory of Open Access Journals (Sweden)

Alexis Sossa Rojas

2015-11-01

Full Text Available The study of the body has led to more than five decades of varied and prolific production by social scientists. However, their theoretical and methodological approaches have been as diverse as these investigations. This article, using concrete examples, reflects on the theoretical and methodological implications applied to the study of the body and corporality in the gyms, and aims to show that there is not a rigid set of embodied practices or one type of gym users; on the contrary, they can vary depending on multiple factors such as economic, cultural, or geographical context. It concludes with the author's opinion that Physical Cultural Studies offers an excellent set of tools to investigate the physical and subjective aspects of gym practices.

Chaos in World Politics: A Reflection

Science.gov (United States)

Ferreira, Manuel Alberto Martins; Filipe, José António Candeias Bonito; Coelho, Manuel F. P.; Pedro, Isabel C.

Chaos theory results from natural scientists' findings in the area of non-linear dynamics. The importance of related models has increased in the last decades, by studying the temporal evolution of non-linear systems. In consequence, chaos is one of the concepts that most rapidly have been expanded in what research topics respects. Considering that relationships in non-linear systems are unstable, chaos theory aims to understand and to explain this kind of unpredictable aspects of nature, social life, the uncertainties, the nonlinearities, the disorders and confusion, scientifically it represents a disarray connection, but basically it involves much more than that. The existing close relationship between change and time seems essential to understand what happens in the basics of chaos theory. In fact, this theory got a crucial role in the explanation of many phenomena. The relevance of this kind of theories has been well recognized to explain social phenomena and has permitted new advances in the study of social systems. Chaos theory has also been applied, particularly in the context of politics, in this area. The goal of this chapter is to make a reflection on chaos theory - and dynamical systems such as the theories of complexity - in terms of the interpretation of political issues, considering some kind of events in the political context and also considering the macro-strategic ideas of states positioning in the international stage.

Closed Cycle Engine Program Used in Solar Dynamic Power Testing Effort

Science.gov (United States)

Ensworth, Clint B., III; McKissock, David B.

1998-01-01

NASA Lewis Research Center is testing the world's first integrated solar dynamic power system in a simulated space environment. This system converts solar thermal energy into electrical energy by using a closed-cycle gas turbine and alternator. A NASA-developed analysis code called the Closed Cycle Engine Program (CCEP) has been used for both pretest predictions and post-test analysis of system performance. The solar dynamic power system has a reflective concentrator that focuses solar thermal energy into a cavity receiver. The receiver is a heat exchanger that transfers the thermal power to a working fluid, an inert gas mixture of helium and xenon. The receiver also uses a phase-change material to store the thermal energy so that the system can continue producing power when there is no solar input power, such as when an Earth-orbiting satellite is in eclipse. The system uses a recuperated closed Brayton cycle to convert thermal power to mechanical power. Heated gas from the receiver expands through a turbine that turns an alternator and a compressor. The system also includes a gas cooler and a radiator, which reject waste cycle heat, and a recuperator, a gas-to-gas heat exchanger that improves cycle efficiency by recovering thermal energy.

Total internal reflection effect on gyrotropic interface

Science.gov (United States)

Glushchenko, Alexander G.; Glushchenko, Eugene P.; Zhukov, Sergey V.

2018-02-01

This article considers the physical features of total internal reflection at gyrotropic and isotropic interfaces for two cases: electrical gyrotropy (plasma) and magnetic gyrotropy (ferrite). It is shown that the plasma magnetization may lead to the formation of the total internal reflection effect, which does not occur in isotropic plasma. The threshold values of the magnetic field, which are necessary for the total internal reflection effect, are determined. The total internal reflection effect on a ferrite-dielectric interface for waves emanating from different angles is observed in various frequency ranges and magnetization fields. The study points out the possibility of changing the total internal reflection angle value in large limits due to a change in the external magnetic field magnitude. The calculation results of the total internal reflection angle dependence on the external magnetic field magnitude are presented. The formulas are elaborated for calculating the total internal reflection angles of different interfaces for gyrotropic and isotropic media. The generalized formulas are defined for calculating the Doppler effect in the gyrotropic media. The study demonstrates how the velocity of the media interface affects the limiting angle of total internal refection.

Reflective thinking in solving an algebra problem: a case study of field independent-prospective teacher

Science.gov (United States)

Agustan, S.; Juniati, Dwi; Yuli Eko Siswono, Tatag

2017-10-01

Nowadays, reflective thinking is one of the important things which become a concern in learning mathematics, especially in solving a mathematical problem. The purpose of this paper is to describe how the student used reflective thinking when solved an algebra problem. The subject of this research is one female student who has field independent cognitive style. This research is a descriptive exploratory study with data analysis using qualitative approach to describe in depth reflective thinking of prospective teacher in solving an algebra problem. Four main categories are used to analyse the reflective thinking in solving an algebra problem: (1) formulation and synthesis of experience, (2) orderliness of experience, (3) evaluating the experience and (4) testing the selected solution based on the experience. The results showed that the subject described the problem by using another word and the subject also found the difficulties in making mathematical modelling. The subject analysed two concepts used in solving problem. For instance, geometry related to point and line while algebra is related to algebra arithmetic operation. The subject stated that solution must have four aspect to get effective solution, specifically the ability to (a) understand the meaning of every words; (b) make mathematical modelling; (c) calculate mathematically; (d) interpret solution obtained logically. To test the internal consistency or error in solution, the subject checked and looked back related procedures and operations used. Moreover, the subject tried to resolve the problem in a different way to compare the answers which had been obtained before. The findings supported the assertion that reflective thinking provides an opportunity for the students in improving their weakness in mathematical problem solving. It can make a grow accuracy and concentration in solving a mathematical problem. Consequently, the students will get the right and logic answer by reflective thinking.

Embedding reflection and learning into agile software development

DEFF Research Database (Denmark)

Babb, Jeffry; Hoda, Rashina; Nørbjerg, Jacob

2014-01-01

The theoretical underpinnings of agile methods emphasize regular reflection as a means to sustainable development pace and continuous learning, but in practice, high iteration pressure can diminish reflection opportunities. The Reflective Agile Learning Model (REALM) combines insights and results...... from studies of agile development practices in India, New Zealand, and the US with Schön’s theory of reflective practice to embed reflection in everyday agile practices....

A call for self-reflection as professors engage the issues of science education reform: An ethnographic study

Science.gov (United States)

Licona, Miguel M.

Science becomes distorted and undemocratic when it is categorized into disciplines that, in turn, perpetuate borders creating conditions of inequality for the general population. Science education reform represents a starting point from which to approach notions of exclusion and inaccessibility. Students not intending to major in science often encounter environments as well as professors that serve to limit their potential and thereby exclude them from greater exposure and participation in the sciences. This qualitative study considers professional practices of professors who hold key positions for the success of science teaching and learning. Through classroom observation, in-depth interviewing and a survey questionnaire, this study sheds fight on the process of science education reform. Participants included six university professors who taught a reformed science course developed under the guidance of a National Science Foundation initiative known as the Collaborative for Excellence in Teacher Preparation. The purpose of this study is to understand the nature of faculty beliefs concerning teaching and learning science for students not intending to major in science, most of whom are elementary education majors. In this study, professors' espoused belief systems were elicited while their mental models that drive behavior were observed in the classroom setting. Incongruencies between theories in practice and theories in use were uncovered and explored. Major implications for who can and cannot learn science within the context of a system that currently serves to pre-select who will succeed are uncovered as a result of this study. The constant comparative method developed by Glaser and Strauss was used to analyze the words of each individual participant as she/he worked to consider the incongruencies in her/his theory and practice (as cited in Maykut & Morehouse, 1994). Self-reflection is identified as key in the process of praxis that will aid professors in their

But do you think I'm cool? Developmental differences in striatal recruitment during direct and reflected social self-evaluations.

Science.gov (United States)

Jankowski, Kathryn F; Moore, William E; Merchant, Junaid S; Kahn, Lauren E; Pfeifer, Jennifer H

2014-04-01

The current fMRI study investigates the neural foundations of evaluating oneself and others during early adolescence and young adulthood. Eighteen early adolescents (ages 11-14, M=12.6) and 19 young adults (ages 22-31, M=25.6) evaluated whether academic, physical, and social traits described themselves directly (direct self-evaluations), described their best friend directly (direct other-evaluations), described themselves from their best friend's perspective (reflected self-evaluations), or in general could change over time (control malleability-evaluations). Compared to control evaluations, both adolescents and adults recruited cortical midline structures during direct and reflected self-evaluations, as well as during direct other-evaluations, converging with previous research. However, unique to this study was a significant three-way interaction between age group, evaluative perspective, and domain within bilateral ventral striatum. Region of interest analyses demonstrated a significant evaluative perspective by domain interaction within the adolescent sample only. Adolescents recruited greatest bilateral ventral striatum during reflected social self-evaluations, which was positively correlated with age and pubertal development. These findings suggest that reflected social self-evaluations, made from the inferred perspective of a close peer, may be especially self-relevant, salient, or rewarding to adolescent self-processing--particularly during the progression through adolescence - and this feature persists into adulthood. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Self-assembled iron oxide nanoparticle multilayer: x-ray and polarized neutron reflectivity

International Nuclear Information System (INIS)

Mishra, D; Benitez, M J; Petracic, O; Badini Confalonieri, G A; Szary, P; Brüssing, F; Devishvili, A; Toperverg, B P; Zabel, H; Theis-Bröhl, K; Vorobiev, A; Konovalov, O; Paulus, M; Sternemann, C

2012-01-01

We have investigated the structure and magnetism of self-assembled, 20 nm diameter iron oxide nanoparticles covered by an oleic acid shell for scrutinizing their structural and magnetic correlations. The nanoparticles were spin-coated on an Si substrate as a single monolayer and as a stack of 5 ML forming a multilayer. X-ray scattering (reflectivity and grazing incidence small-angle scattering) confirms high in-plane hexagonal correlation and a good layering property of the nanoparticles. Using polarized neutron reflectivity we have also determined the long range magnetic correlations parallel and perpendicular to the layers in addition to the structural ones. In a field of 5 kOe we determine a magnetization value of about 80% of the saturation value. At remanence the global magnetization is close to zero. However, polarized neutron reflectivity reveals the existence of regions in which magnetic moments of nanoparticles are well aligned, while losing order over longer distances. These findings confirm that in the nanoparticle assembly the magnetic dipole–dipole interaction is rather strong, dominating the collective magnetic properties at room temperature. (paper)

Self-assembled iron oxide nanoparticle multilayer: x-ray and polarized neutron reflectivity.

Science.gov (United States)

Mishra, D; Benitez, M J; Petracic, O; Badini Confalonieri, G A; Szary, P; Brüssing, F; Theis-Bröhl, K; Devishvili, A; Vorobiev, A; Konovalov, O; Paulus, M; Sternemann, C; Toperverg, B P; Zabel, H

2012-02-10

We have investigated the structure and magnetism of self-assembled, 20 nm diameter iron oxide nanoparticles covered by an oleic acid shell for scrutinizing their structural and magnetic correlations. The nanoparticles were spin-coated on an Si substrate as a single monolayer and as a stack of 5 ML forming a multilayer. X-ray scattering (reflectivity and grazing incidence small-angle scattering) confirms high in-plane hexagonal correlation and a good layering property of the nanoparticles. Using polarized neutron reflectivity we have also determined the long range magnetic correlations parallel and perpendicular to the layers in addition to the structural ones. In a field of 5 kOe we determine a magnetization value of about 80% of the saturation value. At remanence the global magnetization is close to zero. However, polarized neutron reflectivity reveals the existence of regions in which magnetic moments of nanoparticles are well aligned, while losing order over longer distances. These findings confirm that in the nanoparticle assembly the magnetic dipole-dipole interaction is rather strong, dominating the collective magnetic properties at room temperature.

Deformations of closed strings and topological open membranes

NARCIS (Netherlands)

Hofman, C.; Ma, W.K.

2001-01-01

We study deformations of topological closed strings. A well-known example is the perturba- tion of a topological closed string by itself, where the associative OPE product is deformed, and which isgoverned by the WD VV equations. Our main in terest will be closed strings that arise as the

Deformations of closed strings and topological open membranes

NARCIS (Netherlands)

Hofman, C.

We study deformations of topological closed strings. A well-known example is the perturbation of a topological closed string by itself, where the associative OPE product is deformed, and which is governed by the WDVV equations. Our main interest will be closed strings that arise as the boundary

Improving Inquiry Teaching through Reflection on Practice

Science.gov (United States)

Lotter, Christine R.; Miller, Cory

2017-08-01

In this paper, we explore middle school science teachers' learning of inquiry-based instructional strategies through reflection on practice teaching sessions during a summer enrichment program with middle level students. The reflection sessions were part of a larger year-long inquiry professional development program in which teachers learned science content and inquiry pedagogy. The program included a 2-week summer institute in which teachers participated in science content sessions, practice teaching to middle level students, and small group-facilitated reflection sessions on their teaching. For this study, data collection focused on teachers' recorded dialogue during the facilitator - run reflection sessions, the teachers' daily written reflections, a final written reflection, and a written reflection on a videotaped teaching session. We investigated the teachers' reflection levels and the themes teachers focused on during their reflection sessions. Teachers were found to reflect at various reflection levels, from simple description to a more sophisticated focus on how to improve student learning. Recurrent themes point to the importance of providing situated learning environments, such as the practice teaching with immediate reflection for teachers to have time to practice new instructional strategies and gain insight from peers and science educators on how to handle student learning issues.

Media for Reflection

DEFF Research Database (Denmark)

Knudsen, Morten

2016-01-01

This article develops the concept media for reflection in the interest of conceptualizing the interpretative frames that enable and limit reflection in management and leadership education. The concept ‘media for reflection’ allows us to conceptualize the social and cultural mediation of reflection...... without reducing reflection to an effect of the social structures and cultural norms in which it is embedded. Based on the developed theoretical framework, this article analyses how a renaissance ‘mirror for princes’ and contemporary research-based management education mediate reflection. The content...... of the mediations is analysed as well as the societal and organizational background. Furthermore, the means by which the two media enable and limit reflection in different ways is compared. Finally, the article discusses possible implications of the analysis in terms of management and leadership education....

Reflection in Medical Diagnosis: A Literature Review

OpenAIRE

Mamede, Silvia; Schmidt, Henk G.

2017-01-01

Purpose: Reflection in medical diagnosis has been said to prevent errors by minimizing flaws in clinical reasoning. This claim, however, has been much disputed. While some studies show reflective reasoning to improve diagnostic performance, others find it to add nothing. This paper presents a narrative review of the literature on reflection in medical diagnosis aimed at addressing two questions: (1) how reflective reasoning has been conceived in this literature; and (2) what is the effect of ...

Building on Successes: Reflections from Two Approaches to Study Abroad for Undergraduate and Graduate Students

Science.gov (United States)

Linder, Sandra; McGaha, Julie

2013-01-01

This essay offers suggestions for faculty who are designing study abroad (SA) experiences by outlining a three-week Maymester study abroad to Reggio Emilia, Italy, and a semester-long study abroad to Brussels, Belgium. The authors reflect on commonalities in planning, recruiting, preparing students, and conducting each trip, as well as some of the…

Graph topologies on closed multifunctions

Directory of Open Access Journals (Sweden)

Giuseppe Di Maio

2003-10-01

Full Text Available In this paper we study function space topologies on closed multifunctions, i.e. closed relations on X x Y using various hypertopologies. The hypertopologies are in essence, graph topologies i.e topologies on functions considered as graphs which are subsets of X x Y . We also study several topologies, including one that is derived from the Attouch-Wets filter on the range. We state embedding theorems which enable us to generalize and prove some recent results in the literature with the use of known results in the hyperspace of the range space and in the function space topologies of ordinary functions.

Self-reflection Orients Visual Attention Downward.

Science.gov (United States)

Liu, Yi; Tong, Yu; Li, Hong

2017-01-01

Previous research has demonstrated abstract concepts associated with spatial location (e.g., God in the Heavens) could direct visual attention upward or downward, because thinking about the abstract concepts activates the corresponding vertical perceptual symbols. For self-concept, there are similar metaphors (e.g., "I am above others"). However, whether thinking about the self can induce visual attention orientation is still unknown. Therefore, the current study tested whether self-reflection can direct visual attention. Individuals often display the tendency of self-enhancement in social comparison, which reminds the individual of the higher position one possesses relative to others within the social environment. As the individual is the agent of the attention orientation, and high status tends to make an individual look down upon others to obtain a sense of pride, it was hypothesized that thinking about the self would lead to a downward attention orientation. Using reflection of personality traits and a target discrimination task, Study 1 found that, after self-reflection, visual attention was directed downward. Similar effects were also found after friend-reflection, with the level of downward attention being correlated with the likability rating scores of the friend. Thus, in Study 2, a disliked other was used as a control and the positive self-view was measured with above-average judgment task. We found downward attention orientation after self-reflection, but not after reflection upon the disliked other. Moreover, the attentional bias after self-reflection was correlated with above-average self-view. The current findings provide the first evidence that thinking about the self could direct visual-spatial attention downward, and suggest that this effect is probably derived from a positive self-view within the social context.

[An ethical reflection on outreaching mental health care].

Science.gov (United States)

Liégeois, A; Eneman, M

Care providers have a conflicting societal role: on the one hand they must respect the autonomy of individuals with psychiatric problems, but on the other hand they often feel the need to offer these individuals outreaching care. To compile an ethical reflection on some of the ways in which outreaching mental health care interventions can be provided in a responsible manner. This ethical reflection is based on an ethical advice by the Ethics committee for Mental Health Care of the Brothers of Charity in Flanders. The method combines ethical discussion and a study of the relevant literature. A good starting point is a relational view of the human being that emphasises connectedness and involvement. Consequently, the care provider begins to intervene in the care programme by building a trusting relationship with the person with psychiatric problems. This is how these persons, their close family and friends and care providers exercise their responsibility. There is a gradation of responsibility that extends in a continuous line: personal responsibility develops into shared responsibility which can then become vicarious responsibility. On that basis there is also a gradation in the nature of outreaching care; the care providers first make themselves available and give information, then provide advice, negotiate, persuade, increase pressure, and finally take over and force the person with psychiatric problems. The care providers choose in dialogue and in a considered and consistent way for the appropriate form of outreaching care, in line with the degree of responsibility that the person with psychiatric problems can assume.

The effects of types of reflective scaffolding and language proficiency on the acquisition of physics knowledge in a game-based learning environment

Science.gov (United States)

Huang, Tsu-Ting

With the capability of creating a situated and engaging learning environment, video games have been considered as a powerful tool to enhance students' learning outcomes and interest in learning. Yet, little empirical evidence exists to support the effectiveness of video games in learning. Particularly, little attention has been given to the design of specific game elements. Focusing on middle school students, the goal of this study was to investigate the effects of two types of representations of reflective scaffolds (verbal and visual) on students' learning outcomes, game performance, and level of engagement in a video game for physics learning. In addition, the role of students' level of English proficiency was examined to understand whether the effects of reflective scaffolds were influenced by students' language proficiency. Two studies were conducted. Study 1 playtested the game with target players and led to game modification for its use in Study 2, which focused on the effects of different types of reflective scaffolds and level of English proficiency. The results of Study 2 showed that students who received both verbal and visual reflective scaffolds completed the most levels compared to the other groups in the given time. No significant effect of type of reflective scaffolds were found on learning outcomes despite the fact that the pattern of the learning outcomes across conditions was close to prediction. Participants' engagement in gameplay was high regardless of the type of scaffolds they received, their interest in learning physics, and their prior knowledge of physics. The results of video analysis also showed that the game used in this study was able to engage students not only in gameplay but also in learning physics. Finally, English proficiency functioned as a significant factor moderating the effects of scaffolds, learning outcomes and game performance. Students with limited English proficiency benefited more from visual reflective scaffolds than

Close-Spaced High Temperature Knudsen Flow.

Science.gov (United States)

1984-06-15

study of discharge processes in Knudsen mode (collisionless), thermionic energy converters. Areas of research involve mechanism for reducing the...The mechanisms we have chosen to study are: reduction of space-charge through a very close inter- electrode gap (less than 10 microns); transport and...AD-AI4U 471 :NNTIM R~ A Rl M ,i; ,11 , i J)W R8 1070 1 I~ "i E~Hhhh IIt Ll ~ : RASOR ASSOCIATES, INC.- AFOSR.TR. 84-1070 NSR-22-2 CLOSE -SPACED HIGH

Beyond the Margins: Reflective Writing and Development of Reflective Capacity in Medical Education

Science.gov (United States)

Reis, Shmuel P.

2010-01-01

Reflective capacity has been described as an essential characteristic of professionally competent clinical practice, core to ACGME competencies. Reflection has been recently linked to promoting effective use of feedback in medical education and associated with improved diagnostic accuracy, suggesting promising outcomes. There has been a proliferation of reflective writing pedagogy within medical education to foster development of reflective capacity, extend empathy with deepened understanding of patients’ experience of illness, and promote practitioner well-being. At Alpert Med, “interactive” reflective writing with guided individualized feedback from interdisciplinary faculty to students’ reflective writing has been implemented in a Doctoring course and Family Medicine clerkship as an educational method to achieve these aims. Such initiatives, however, raise fundamental questions of reflection definition, program design, efficacy of methods, and outcomes assessment. Within this article, we consider opportunities and challenges associated with implementation of reflective writing curricula for promotion of reflective capacity within medical education. We reflect upon reflection. PMID:20407840

Diurnal Reflectance Changes in Vegetation Observed with AVIRIS

Science.gov (United States)

Vanderbilt, V. C.; Ambrosia, V. G.; Ustin, S. L.

1998-01-01

Among the most important short-term dynamic biological processes are diurnal changes in canopy water relations. Plant regulation of water transport through stomatal openings affects other gaseous transport processes, often dramatically decreasing photosynthetic fixation of carbon dioxide during periods of water stress. Water stress reduces stomatal conductance of water vapor through the leaf surface and alters the diurnal timing of stomatal opening. Under non-water stressed conditions, stomates typically open soon after dawn and transpire water vapor throughout the daylight period. During stress periods, stomates may close for part of the day, generally near mid-day. Under prolonged stress conditions, stomatal closure shifts to earlier times during the day; stomates may close by mid-morning and remain closed until the following morning - or remain closed entirely. Under these conditions the relationship between canopy greenness (e.g., measured with a vegetation index or by spectral mixture analysis) and photosynthetic fixation of carbon is lost and the remotely sensed vegetation metric is a poor predictor of gas exchange. Prediction of stomatal regulation and exchange of water and trace gases is critical for ecosystem and climate models to correctly estimate budgets of these gases and understand or predict other processes like gross and net ecosystem primary production. Plant gas exchange has been extensively studied by physiologists at the leaf and whole plant level and by biometeorologists at somewhat larger scales. While these energy driven processes follow a predictable if somewhat asymmetric diurnal cycle dependent on soil water availability and the constraints imposed by the solar energy budget, they are nonetheless difficult to measure at the tree and stand levels using conventional methods. Ecologists have long been interested in the potential of remote sensing for monitoring physiological changes using multi-temporal images. Much of this research has

Infrared reflectance studies of hillock-like porous zinc oxide thin films

International Nuclear Information System (INIS)

Ching, C.G.; Lee, S.C.; Ng, S.S.; Hassan, Z.; Abu Hassan, H.

2013-01-01

We investigated the infrared (IR) reflectance characteristics of hillock-like porous zinc oxide (ZnO) thin films on silicon substrates. The IR reflectance spectra of the porous samples exhibited an extra resonance hump in the reststrahlen region of ZnO compared with the as-grown sample. Oscillation fringes with different behaviors were also observed in the non-reststrahlen region of ZnO. Standard multilayer optic technique was used with the effective medium theory to analyze the observations. Results showed that the porous ZnO layer consisted of several sublayers with different porosities and thicknesses. These findings were confirmed by scanning electron microscopy measurements. - Highlights: • Multilayer porous assumption qualitatively increased the overall spectra fitting. • IR reflectance is a sensitive method to probe the multilayer porous structure. • Hillock-like porous ZnO thin films fabricated using electrochemical etching method. • The thickness and porosity of the samples were determined. • Formation of extra resonance hump was due to splitting of reststrahlen band

The Importance of Reflective Practice in Nursing

Directory of Open Access Journals (Sweden)

Lauren Caldwell

2013-01-01

Full Text Available Reflection is an essential attribute for the development of autonomous, critical, and advanced practitioners (Mantzoukas & Jasper, 2004. According to Chong (2009, “Reflective practice should be a continuous cycle in which experience and reflection on experiences are inter-related” (p. 112. Studies have shown that nurses who take the time to reflect on their daily experiences provide enhanced nursing care, have a better understanding of theiractions, which in return develops their professional skills (Hansebo & Kihlgren, 2001. Reflective practice is the ability to examine ones actions and experiences with the outcome of developing their practice and enhancing clinicalknowledge. Reflective practice affects all levels of nursing, from students, to advanced practice nursing students, aswell as practicing nurses. Reflective practice is an important component of the nursing curriculum. Research has shown the relationship between student nurses and their mentors is vital. In order for reflection to be effective open-mindedness, courage, and a willingness to accept, and act on, criticism must be present (Bulmam, Lathlean, & Gobbi, 2012. This paper will explore the current literature and implications related to reflective practice in nursing.

Preliminary Studies on the Reflectance Characteristics of graphene/SiO2 under Different Applied Voltages for Optical Modulation Applications

Science.gov (United States)

Beh, K. P.; Yam, F. K.; Abdalrheem, Raed; Ng, Y. Z.; Suhaimi, F. H. A.; Lim, H. S.; Mat Jafri, M. Z.

2018-04-01

A preliminary study on the interband transition of graphene was done via reflectance spectra of graphene/SiO2 sample at various applied potential. Prior to that, Raman spectroscopy and four-point probe measurement was done on graphene/SiO2 sample. It was found that the sample consisted of monolayer graphene with sheet resistance around 402.32 Ω/□. Post-processing of the reflectance data lead to the plot of ratio of change in reflectance towards reflectance at 0 V (ΔR/R) against applied potential. From there, the ratio increases along with applied potential, indicative of higher absorption due to interband transition.

Assessing reflective thinking and approaches to learning.

Science.gov (United States)

Dunn, Louise; Musolino, Gina M

2011-01-01

Facilitation of reflective practice is critical for the ongoing demands of health care practitioners. Reflective thinking concepts, grounded in the work of Dewey and Schön, emphasize critical reflection to promote transformation in beliefs and learning necessary for reflective practice. The Reflective Thinking Questionnaire (QRT) and Revised Study Process Questionnaire (RSPQ-2F) assess skill aspects of professional reasoning, with promise for measuring changes over time. The purpose of this study was to examine the reliability and responsiveness and the model validity of reflective thinking and approaches to learning measures for U.S. health professions students enrolled in entry-level occupational (MOT) and physical therapy (DPT) programs. This measurement study addressed reliability and responsiveness of two measures, the QRT and RSPQ-2F, for graduate health professionals. A convenience sample of 125 MOT and DPT students participated in the two-measure, test-retest investigation, with electronic data collection. Outcomes support the stability of the four-scale QRT (ICC 0.63 to 0.82) and the two-scale RSPQ-2F (ICC 0.91 and 0.87). Descriptive data supporting responsiveness are presented. With noted limitations, the results support the use of the QRT and RSPQ-2F measures to assess changes in reflective thinking and approaches to learning. Measurement of these learning outcomes furthers our understanding and knowledge about instructional strategies, development of professional reasoning, and fostering of self-directed learning within MOT and DPT programs.

Early subsidence of shape-closed hip arthroplasty stems is associated with late revision. A systematic review and meta-analysis of 24 RSA studies and 56 survival studies.

Science.gov (United States)

van der Voort, Paul; Pijls, Bart G; Nieuwenhuijse, Marc J; Jasper, Jorrit; Fiocco, Marta; Plevier, Josepha W M; Middeldorp, Saskia; Valstar, Edward R; Nelissen, Rob G H H

2015-01-01

Few studies have addressed the association between early migration of femoral stems and late aseptic revision in total hip arthroplasty. We performed a meta-regression analysis on 2 parallel systematic reviews and meta-analyses to determine the association between early migration and late aseptic revision of femoral stems. Of the 2 reviews, one covered early migration data obtained from radiostereometric analysis (RSA) studies and the other covered long-term aseptic revision rates obtained from survival studies with endpoint revision for aseptic loosening. Stems were stratified according to the design concept: cemented shape-closed, cemented force-closed, and uncemented. A weighted regression model was used to assess the association between early migration and late aseptic revision, and to correct for confounders. Thresholds for acceptable and unacceptable migration were determined in accordance with the national joint registries (≤ 5% revision at 10 years) and the NICE criteria (≤ 10% revision at 10 years). 24 studies (731 stems) were included in the RSA review and 56 studies (20,599 stems) were included in the survival analysis review. Combining both reviews for the 3 design concepts showed that for every 0.1-mm increase in 2-year subsidence, as measured with RSA, there was a 4% increase in revision rate for the shape-closed stem designs. This association remained after correction for age, sex, diagnosis, hospital type, continent, and study quality. The threshold for acceptable migration of shape-closed designs was defined at 0.15 mm; stems subsiding less than 0.15 mm in 2 years had revision rates of less than 5% at 10 years, while stems exceeding 0.15 mm subsidence had revision rates of more than 5%. There was a clinically relevant association between early subsidence of shape-closed femoral stems and late revision for aseptic loosening. This association can be used to assess the safety of shape-closed stem designs. The published research is not sufficient

Self-Reflection and Academic Performance: Is There a Relationship?

Science.gov (United States)

Lew, Magdeleine D. N.; Schmidt, Henk G.

2011-01-01

The purposes of the present study were two-fold: first, to evaluate whether reflection journal writing was effective in promoting self-reflection and learning, and whether students become better at self-reflection if they engage continuously in reflection journal writing. To that end, the reflection journals of 690 first-year applied science…

Interviews on end-of-life care with older people: reflections on six european studies

NARCIS (Netherlands)

Pleschberger, S.; Seymour, J.E.; Payne, S.; Deschepper, R.; Onwuteaka-Philipsen, B.D.; Rurup, M.L.

2011-01-01

Qualitative research provides important insights into the experiences and perspectives of older people on end-of-life issues, but such research is methodologically and ethically complex. We offer a set of reflections from six end-of-life care studies conducted with older people in four European

Reflection on an interprofessional communitybased participatory research project

Directory of Open Access Journals (Sweden)

A Rhoda

2016-11-01

Full Text Available Background. A collaborative interprofessional research project that involved community members was beneficial to community development.Objective. To draw upon the experiences of academics relating to their involvement in an interprofessional community-based participatory research(CBPR project.Methods. A Delphi study was applied as a self-reflective evaluation process to reach consensus on the lessons learnt from participation in a CBPR project. Round one of the Delphi employed closed-ended questions and the responses were analysed descriptively using Microsoft Excel (USA. The second round consisted mainly of open-ended questions and responses, and was analysed qualitatively. Ethical clearance was obtained from the University of the Western Cape research committee.Results. Based on round one of the Delphi study, it became evident that recognition of the community as a unit of identity, addressing health from physical, emotional and social perspectives and formation of long-term commitments were the CBPR principles most applied. Disseminating information to all partners and facilitation of the collaborative equitable involvement of all partners in all phases of the research were the principles least applied. Themes that emerged from the second round of the Delphi included the identification of clear objectives based on the needs of the community, a shift from identification of the needs of the community to the implementation of strategies, and the creation of capacity-building opportunities for all stakeholders.Conclusion. In a reflection on the research process, the interprofessional team of academics found that the basics of CBPR should be attended to first. A focus on clear objectives, implementation strategies and capacity building is important in CBPR.

Skin lesions diagnostics by on diffuse reflection spectres using computational algorithms: a preliminary study

International Nuclear Information System (INIS)

Orozco-Guillen, E.E.; Delgado-Atencio, J.A.; Vazquez-Montiel, S.; Castro-Ramos, J.; Villanueva-Luna, E.; Gutierrez-Delgado, F.

2009-01-01

The determination of diffuse reflection spectrum on human skin in the spectral range from 400nm-1000nm using an optical fiber spectrometers is a non-invasive technique widely used to study the optical parameters of this tissue, provides information about the absorption and scattering properties of light that can be employed to study the morphology and physiology of the tissue and to detect and diagnose skin diseases in early stages. In this paper a computational algorithm for the selection of the most important attributes of diffuse reflection spectra of human skin obtained with an experimental system that basically consists of a spectrometer, a white light source and bifurcated fiber optic probe that allows send and collect light. To classify the spectral signal was designed a Matlab2006 graphical interface which use support vector machines and algorithm for selecting attributes that allows to achieve a sensitivity and specificity exceeding 80% and 85% of accuracy in the classification. (Author)

Cr/B{sub 4}C multilayer mirrors: Study of interfaces and X-ray reflectance

Energy Technology Data Exchange (ETDEWEB)

Burcklen, C.; Meltchakov, E.; Jérome, A.; Rossi, S. de; Delmotte, F. [Laboratoire Charles Fabry, Institut d' Optique Graduate School, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex (France); Soufli, R. [Laboratoire Charles Fabry, Institut d' Optique Graduate School, CNRS, Université Paris-Saclay, 91127 Palaiseau Cedex (France); Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Dennetiere, D.; Polack, F.; Capitanio, B.; Thomasset, M. [Synchrotron SOLEIL, L' Orme des Merisiers, Saint Aubin, BP 48F-91192 Gif sur Yvette Cedex (France); Gullikson, E. [Center for X-ray Optics, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd., Berkeley, California 94720 (United States)

2016-03-28

We present an experimental study of the effect of layer interfaces on the x-ray reflectance in Cr/B{sub 4}C multilayer interference coatings with layer thicknesses ranging from 0.7 nm to 5.4 nm. The multilayers were deposited by magnetron sputtering and by ion beam sputtering. Grazing incidence x-ray reflectometry, soft x-ray reflectometry, and transmission electron microscopy reveal asymmetric multilayer structures with a larger B{sub 4}C-on-Cr interface, which we modeled with a 1–1.5 nm thick interfacial layer. Reflectance measurements in the vicinity of the Cr L{sub 2,3} absorption edge demonstrate fine structure that is not predicted by simulations using the currently tabulated refractive index (optical constants) values for Cr.

The impact of culture on adaptive versus maladaptive self-reflection.

Science.gov (United States)

Grossmann, Igor; Kross, Ethan

2010-08-01

Although recent findings indicate that people can reflect either adaptively or maladaptively over negative experiences, extant research has not examined how culture influences this process. We compared the self-reflective practices of Russians (members of an interdependent culture characterized by a tendency to brood) and Americans (members of an independent culture in which self-reflection has been studied extensively). We predicted that self-reflection would be associated with less-detrimental outcomes among Russians because they self-distance more when analyzing their feelings than Americans do. Findings from two studies supported these predictions. In Study 1, self-reflection was associated with fewer depressive symptoms among Russians than among Americans. In Study 2, Russians displayed less distress and a more adaptive pattern of construals than Americans after reflecting over a recent negative event. In addition, they self-distanced more than Americans while analyzing their feelings, and self-distancing mediated the cultural differences in self-reflection. These findings demonstrate how culture shapes the way people reflect over negative experiences.

Smooth and rough Proteus mirabilis lipopolysaccharides studied by total internal reflection ellipsometry

International Nuclear Information System (INIS)

Gleńska-Olender, J.; Dworecki, K.; Sęk, S.; Kwinkowski, M.; Kaca, W.

2013-01-01

Total internal reflection ellipsometry (TIRE), a label-free optical detection technique for studying interactions between biomolecules, was used to examine the adsorption of various forms of lipopolysaccharides (LPSs) isolated from Proteus mirabilis S1959, R110, and R45 strains on a gold surface. The thickness of the adsorbed layers was determined by TIRE, with the average values for S1959, R110, and R45 LPS layers being 78 ± 5, 39 ± 3, and 12 ± 2 nm, respectively. The thickness of LPS layers corresponds to the presence and length of O-specific parts in P. mirabilis LPS molecules. Atomic force microscopy was used as a complementary technique for visualizing lipopolysaccharides on the surface. Force measurements seem to confirm the data obtained from TIRE experiments. - Highlights: • Proteus mirabilis lipopolysaccharides were adsorbed on the gold surface. • Thickness of adsorbed layers was determined by total internal reflection ellipsometry. • Atomic force microscopy was used to visualize lipopolysaccharide build-up on gold surface. • Time is important in the evolution of biomolecular film thickness created on gold surface

Smooth and rough Proteus mirabilis lipopolysaccharides studied by total internal reflection ellipsometry

Energy Technology Data Exchange (ETDEWEB)

Gleńska-Olender, J., E-mail: joannaglenska@wp.pl [Institute of Biology, Jan Kochanowski University, 25-406 Kielce (Poland); Świętokrzyski Biobank, Regional Science and Technology Center, 26-060 Chęciny (Poland); Dworecki, K. [Institute of Physics, Jan Kochanowski University, 25-406 Kielce (Poland); Sęk, S. [Department of Chemistry, University of Warsaw, 02-093 Warsaw (Poland); Kwinkowski, M.; Kaca, W. [Institute of Biology, Jan Kochanowski University, 25-406 Kielce (Poland)

2013-12-02

Total internal reflection ellipsometry (TIRE), a label-free optical detection technique for studying interactions between biomolecules, was used to examine the adsorption of various forms of lipopolysaccharides (LPSs) isolated from Proteus mirabilis S1959, R110, and R45 strains on a gold surface. The thickness of the adsorbed layers was determined by TIRE, with the average values for S1959, R110, and R45 LPS layers being 78 ± 5, 39 ± 3, and 12 ± 2 nm, respectively. The thickness of LPS layers corresponds to the presence and length of O-specific parts in P. mirabilis LPS molecules. Atomic force microscopy was used as a complementary technique for visualizing lipopolysaccharides on the surface. Force measurements seem to confirm the data obtained from TIRE experiments. - Highlights: • Proteus mirabilis lipopolysaccharides were adsorbed on the gold surface. • Thickness of adsorbed layers was determined by total internal reflection ellipsometry. • Atomic force microscopy was used to visualize lipopolysaccharide build-up on gold surface. • Time is important in the evolution of biomolecular film thickness created on gold surface.

Measurement of transepidermal water loss (TEWL) in cats with experimental skin barrier dysfunction using a closed chamber system.

Science.gov (United States)

Momota, Yutaka; Shimada, Kenichiro; Gin, Azusa; Matsubara, Takako; Azakami, Daigo; Ishioka, Katsumi; Nakamura, Yuka; Sako, Toshinori

2016-10-01

A closed chamber evaporimeter is suitable for measuring transepidermal water loss (TEWL) in cats because of the compact device size, tolerance to sudden movement and short measuring time. TEWL is a representative parameter for skin barrier dysfunction, which is one of the clinical signs of atopic dermatitis in humans and dogs. Measurement of feline TEWL has been reported, but applicability of this parameter has not been validated. The aims of this study were to determine if tape stripping is a valid experimental model in cats for studying TEWL and to determine if a closed chambered system is a suitable measurement tool for cats. Ten clinically normal cats. In order to evaluate variation of the measured values, TEWL was measured at the right and left side of the three clipped regions (axillae, lateral thigh and groin). Subsequently, TEWL was measured using sequential tape stripping of the stratum corneum as a model of acute barrier disruption. The variations between both sides of the three regions showed no significant difference. Sequential tape stripping was associated with increasing values for TEWL. Feline TEWL was shown to reflect changes in the skin barrier in an experimental model using a closed chamber system and has the potential for evaluating skin barrier function in cats with skin diseases. © 2016 ESVD and ACVD.

Exploiting total internal reflection geometry for efficient optical modulation of terahertz light

Directory of Open Access Journals (Sweden)

Xudong Liu

2016-10-01

Full Text Available Efficient methods to modulate terahertz (THz light are essential for realizing rapid THz imaging and communication applications. Here we report a novel THz modulator which utilizes the evanescent wave in a total internal reflection setup coupled with a conductive interface to enhance the attenuation efficiency of THz light. This approach makes it possible to achieve close to 100% modulation with a small interface conductivity of 12 mS. The frequency dependence of this technique is linked to the optical properties of the materials: a material with close to frequency independent conductivity that is also controllable will result in an achromatic modulation response, and the device performance can be optimized further by tuning the internal reflection angle. In this work, we focus on applying the technique in the terahertz frequency range. Using an LED array with a pump intensity of 475 mW/cm2 to produce carriers in a silicon wafer, we have achieved a modulation depth of up to 99.9% in a broad frequency range of 0.1 THz–0.8 THz. The required pumping power for the generation of the required free carriers is low because the sheet conductivity needed is far less than required for traditional transmission techniques. Consequently, the device can be modulated by an LED making it a very practical, low cost, and scalable solution for THz modulation.

A reflective-backing-free metamaterial absorber with broadband response

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Cuilian Xu

2017-06-01

Full Text Available In this paper, we propose a polarization-independent and broadband perfect infrared (IR metamaterial absorber (MA without reflective backing. The proposed absorber is a periodic meta-atom array consisting of metal-dielectric-multilayer truncated cones which can absorb 80% EM wave from 50.70 to 81.87THz, while transmit 80% EM wave from 0 to 37.71THz. With the decreasing of frequency, the transmissivity increases, which is close to 100% from 0 to 5THz. We can broaden the absorption bandwidth of the MA by cascading multi-layers truncated cones. Furthermore, the proposed IR MA promises to be one desirable stealth material for radar-IR compatibility.

Electro-optic study of PZT ferroelectric ceramics using modulation of reflected light

Science.gov (United States)

Kniazkov, A. V.

2016-04-01

Electro-optic coefficients of variations in the refractive index of PZT and PLZT ceramic materials induced by ac electric field are estimated using modulation of reflected light. The electro-optic coefficients of PLZT ceramics measured with the aid of conventional birefringence using the phase shift of transmitted radiation and the proposed method of birefringence using the modulation of reflected light are compared.

Detailed Study of Closed Stator Slots for a Direct-Driven Synchronous Permanent Magnet Linear Wave Energy Converter

Directory of Open Access Journals (Sweden)

Erik Lejerskog

2014-01-01

Full Text Available The aim of this paper is to analyze how a permanent magnet linear generator for wave power behaves when the stator slots are closed. The usual design of stator geometry is to use open slots to maintain a low magnetic leakage flux between the stator teeth. By doing this, harmonics are induced in the magnetic flux density in the air-gap due to slotting. The closed slots are designed to cause saturation, to keep the permeability low. This reduces the slot harmonics in the magnetic flux density, but will also increase the flux leakage between the stator teeth. An analytical model has been created to study the flux through the closed slots and the result compared with finite element simulations. The outcome shows a reduction of the cogging force and a reduction of the harmonics of the magnetic flux density in the air-gap. It also shows a small increase of the total magnetic flux entering the stator and an increased magnetic flux leakage through the closed slots.

Study of inhomogeneous solid adlayers at electrolyte-solid interfaces using differential reflectance spectroscopy. Progress report, July 1, 1977--February 28, 1978

International Nuclear Information System (INIS)

Sari, S.O.

1978-03-01

Differential reflectance spectroscopy has been used to study interactions at liquid-solid and air-solid interfaces. The aim is to examine a number of properties of adsorbed solid and molecular interlayers formed at such boundaries. Differential optical techniques have not previously been used to a large degree to investigate details of interfacial properties. However, in conjunction with x-ray and electron analysis these approaches are important for examining both electronic structure and adsorption-adhesion mechanics of surface coverings even if these are only a few atomic diameters in thickness. Such layers are induced in experiments by electronic circuitry devised to add or subtract controlled amounts of adlayer through reactions at electrolyte-solid interfaces. The purpose is to supply new information of a basic nature concerning interfacial properties. This can be important since crystal phases of some materials exist only in thin surface coverings. Thus, a connection of this work may well be important to new thin-layer technology. Moreover, an important relation seems well established to problems in solar energy. It is known, for example, that interfacial layers modify gas evolution at some electrolyte-oxide boundaries and thus their study is closely relevant to improvement of some new fuel production schemes

Altered functional connectivity during self- and close other-reflection in patients with bipolar disorder with past psychosis and patients with schizophrenia

NARCIS (Netherlands)

Zhang, Liwen; Meer, van der Lisette; Opmeer, Esther M.; Marsman, Jan-Bernard C.; Ruhe, Henricus G.; Aleman, Andre

2016-01-01

Disturbances in implicit self-processing have been reported both in psychotic patients with bipolar disorder (BD) and schizophrenia. It remains unclear whether these two psychotic disorders show disturbed functional connectivity during explicit self-reflection, which is associated with social

USING CLOSE WHITE DWARF + M DWARF STELLAR PAIRS TO CONSTRAIN THE FLARE RATES IN CLOSE STELLAR BINARIES

Energy Technology Data Exchange (ETDEWEB)

Morgan, Dylan P.; West, Andrew A. [Astronomy Department, Boston University, 725 Commonwealth Ave, Boston, MA 02215 (United States); Becker, Andrew C., E-mail: dpmorg@bu.edu [Department of Astronomy, University of Washington, Box 351580, Seattle, WA 98195 (United States)

2016-05-01

We present a study of the statistical flare rates of M dwarfs (dMs) with close white dwarf (WD) companions (WD+dM; typical separations <1 au). Our previous analysis demonstrated that dMs with close WD companions are more magnetically active than their field counterparts. One likely implication of having a close binary companion is increased stellar rotation through disk-disruption, tidal effects, and/or angular momentum exchange; increased stellar rotation has long been associated with an increase in stellar activity. Previous studies show a strong correlation between dMs that are magnetically active (showing H α in emission) and the frequency of stellar flare rates. We examine the difference between the flare rates observed in close WD+dM binary systems and field dMs. Our sample consists of a subset of 181 close WD+dM pairs from Morgan et al. observed in the Sloan Digital Sky Survey Stripe 82, where we obtain multi-epoch observations in the Sloan ugriz -bands. We find an increase in the overall flaring fraction in the close WD+dM pairs (0.09 ± 0.03%) compared to the field dMs (0.0108 ± 0.0007%) and a lower flaring fraction for active WD+dMs (0.05 ± 0.03%) compared to active dMs (0.28 ± 0.05%). We discuss how our results constrain both the single and binary dM flare rates. Our results also constrain dM multiplicity, our knowledge of the Galactic transient background, and may be important for the habitability of attending planets around dMs with close companions.

Reflectance, absorbance and transmittance spectra of bermudagrass and manilagrass turfgrass canopies.

Science.gov (United States)

Volterrani, Marco; Minelli, Alberto; Gaetani, Monica; Grossi, Nicola; Magni, Simone; Caturegli, Lisa

2017-01-01

Leaves act as a primary organ for the interception of solar radiation and their spatial arrangement determines how the plant canopy interacts with light. Many studies have been carried out on the penetration of radiation into crops however to date, few results are available on turfgrasses, mainly due to the difficulties of introducing sensors into the turf without disturbing the natural position of the leaves. In the present research two warm season turfgrasses, hybrid bermudagrass (Cynodon dactylon × transvaalensis) 'Patriot' and manilagrass (Zoysia matrella) 'Zeon', were studied. The aim was to describe their canopy architecture grown with minimal disturbance to the natural arrangement of the leaves and stems, and to determine the potential effects of canopy architecture on light penetration and reflectance. Radiometric measurements were carried out at eight different profile levels of turfgrasses that were up to 12 cm tall. A LI-COR 1800 spectroradiometer with an optical fiber cable and a 7 mm diameter sensor was used. Measurements were carried out in the 390-1100 nm region at 5 nm intervals. The LAI value was higher for the manilagrass (9.0) than for the hybrid bermudagrass (5.6). The transmitted radiation was found to be closely dependent on downward cumulative LAI. Despite a more upright habit (mean insertion angle of 22.4° ±3.4), Zoysia matrella showed a higher NIR reflectance compared to Cdxt, which has a horizontal leaf arrangement (mean insertion angle 62.1° ± 9.6). The species studied showed substantial differences both in terms of phytometric characteristics and in the capacity to attenuate solar radiation.

Low-temperature relative reflectivity measurements of reflective and scintillating foils used in rare event searches

Science.gov (United States)

Langenkämper, A.; Ulrich, A.; Defay, X.; Feilitzsch, F. v.; Lanfranchi, J.-C.; Mondragón, E.; Münster, A.; Oppenheimer, C.; Potzel, W.; Roth, S.; Schönert, S.; Steiger, H.; Trinh Thi, H. H.; Wawoczny, S.; Willers, M.; Zöller, A.

2018-03-01

In this work we investigate the reflectivity of highly reflective multilayer polymer foils used in the CRESST experiment. The CRESST experiment searches directly for dark matter via operating scintillating CaWO4 crystals as targets for elastic dark matter-nucleon scattering. In order to suppress background events, the experiment employs the so-called phonon-light technique which is based on the simultaneous measurement of the heat signal in the main CaWO4 target crystal and of the emitted scintillation light with a separate cryogenic light detector. Both detectors are surrounded by a highly reflective and scintillating multilayer polymer foil to increase the light collection efficiency and to veto surface backgrounds. While this study is motivated by the CRESST experiment, the results are also relevant for other rare event searches using scintillating cryogenic bolometers in the field of the search of dark matter and neutrinoless double beta decay (0 νββ). In this work a dedicated experiment has been set up to determine the relative reflectivity at 300 K and 20 K of three multilayer foils ("VM2000", "VM2002", "Vikuiti") produced by the company 3M. The intensity of a light beam reflected off the foil is measured with a CCD camera. The ratio of the intensities at 300 K and 20 K corresponds to the relative reflectivity change. The measurements performed in this work show no variation of the reflectivity with temperature at a level of ∼1%.

The Effect of a Self-Reflection and Insight Program on the Nursing Competence of Nursing Students: A Longitudinal Study.

Science.gov (United States)

Pai, Hsiang-Chu

2015-01-01

Nurses have to solve complex problems for their patients and their families, and as such, nursing care capability has become a focus of attention. The aim of this longitudinal study was to develop a self-reflection practice exercise program for nursing students to be used during clinical practice and to evaluate the effects of this program empirically and longitudinally on change in students' clinical competence, self-reflection, stress, and perceived teaching quality. An additional aim was to determine the predictors important to nursing competence. We sampled 260 nursing students from a total of 377 practicum students to participate in this study. A total of 245 students nurse completed 4 questionnaires, Holistic Nursing Competence Scale, Self-Reflection and Insight Scale, Perceived Stress Scale, and Clinical Teaching Quality Scale, at 2, 4, and 6 months after clinical practice experience. Generalized estimating equation models were used to examine the change in scores on each of the questionnaires. The findings showed that, at 6 months after clinical practice, nursing competence was significantly higher than at 2 and 4 months, was positively related to self-reflection and insight, and was negatively related to practice stress. Nursing students' competence at each time period was positively related to clinical teachers' instructional quality at 4 and 6 months. These results indicate that a clinical practice program with self-reflection learning exercise improves nursing students' clinical competence and that nursing students' self-reflection and perceived practice stress affect their nursing competence. Nursing core competencies are enhanced with a self-reflection program, which helps nursing students to improve self-awareness and decrease stress that may interfere with learning. Further, clinical practice experience, self-reflection and insight, and practice stress are predictors of nursing students' clinical competence. Copyright © 2015 Elsevier Inc. All

The educational practice of preceptors in healthcare residencies: a study on reflective practice

Directory of Open Access Journals (Sweden)

Kátia Regina Barros RIBEIRO

Full Text Available The purpose of this article was to reflect on the practice of preceptorship as an educational practice in the training and qualifications of professional health information for the public health system. This is a theoretical reflection with support in the literature. The teacher addresses the teaching-learning process and transforms the activities in the work on educational moments. In this area arise questions about what is being preceptor and their role in health education. It is necessary to teach knowledge beyond the content of the discipline, and reflecting about preceptorship as an educational practice in the workplace, the preceptor needs pedagogical preparation. Herewith, being a preceptor means being a teacher? This reflection places us in front of a problem present in our daily exercise, which is the pedagogical training of those who teach for a transformation of practice in health.

Simulations of wave propagation and disorder in 3D non-close-packed colloidal photonic crystals with low refractive index contrast.

Science.gov (United States)

Glushko, O; Meisels, R; Kuchar, F

2010-03-29

The plane-wave expansion method (PWEM), the multiple-scattering method (MSM) and the 3D finite-difference time-domain method (FDTD) are applied for simulations of propagation of electromagnetic waves through 3D colloidal photonic crystals. The system investigated is not a "usual" artificial opal with close-packed fcc lattice but a dilute bcc structure which occurs due to long-range repulsive interaction between electrically charged colloidal particles during the growth process. The basic optical properties of non-close-packed colloidal PhCs are explored by examining the band structure and reflection spectra for a bcc lattice of silica spheres in an aqueous medium. Finite size effects and correspondence between the Bragg model, band structure and reflection spectra are discussed. The effects of size, positional and missing-spheres disorder are investigated. In addition, by analyzing the results of experimental work we show that the fabricated structures have reduced plane-to-plane distance probably due to the effect of gravity during growth.

Reflection groups

International Nuclear Information System (INIS)

Eggermont, G.

2006-01-01

In 2005, PISA organised proactive meetings of reflection groups on involvement in decision making, expert culture and ethical aspects of radiation protection.All reflection group meetings address particular targeted audiences while the output publication in book form is put forward

In situ anodization of aluminum surfaces studied by x-ray reflectivity and electrochemical impedance spectroscopy

International Nuclear Information System (INIS)

Bertram, F.; Evertsson, J.; Messing, M. E.; Mikkelsen, A.; Lundgren, E.; Zhang, F.; Pan, J.; Carlà, F.; Nilsson, J.-O.

2014-01-01

We present results from the anodization of an aluminum single crystal [Al(111)] and an aluminum alloy [Al 6060] studied by in situ x-ray reflectivity, in situ electrochemical impedance spectroscopy and ex situ scanning electron microscopy. For both samples, a linear increase of oxide film thickness with increasing anodization voltage was found. However, the slope is much higher in the single crystal case, and the break-up of the oxide film grown on the alloy occurs at a lower anodization potential than on the single crystal. The reasons for these observations are discussed as are the measured differences observed for x-ray reflectivity and electrochemical impedance spectroscopy.

Reflections on Teaching Periodic Table Concepts: A Case Study of Selected Schools in South Africa

Science.gov (United States)

Mokiwa, Hamza Omari

2017-01-01

The Periodic Table of Elements is central to the study of modern Physics and Chemistry. It is however, considered by teachers as difficult to teach. This paper reports on a case study exploring reflections on teaching periodic table concepts in five secondary schools from South Africa. Qualitative methodology of interviews and document analysis…

Reflection seismic studies over the end-glacial Burträsk fault, Skellefteå, Sweden

Directory of Open Access Journals (Sweden)

C. Juhlin

2011-01-01

Full Text Available Reflection seismic data were acquired along a ca. 22 km long profile over the end-glacial Burträsk fault with a nominal receiver and source spacing of 20 m. A steeply dipping reflection can be correlated to the Burträsk fault, indicating that the fault dips at about 55° to the southeast near the surface. The reflection from the fault is rather poorly imaged, probably due to a lateral offset in the fault of about 1 km at this location and the crookedness of the seismic profile in the vicinity of the fault. A more pronounced steeply dipping reflection is observed about 4 km southeast of the Burträsk fault. Based on its correlation with a topographic low at the surface this reflection is interpreted to originate from a fracture zone. There are no signs of large displacements along this zone as the glacial ice receded, but earthquakes could be associated with it today. Other reflections on the processed seismic section may originate from changes in lithological variations in the supra-crustal rocks or from intrusions of more mafic rock. Constraints on the fault geometry provided by the reflection seismic data will help determine what stresses were required to activate the fault when the major rupture along it occurred ca. 9500 years ago.

Self-reflection and academic performance: is there a relationship?

NARCIS (Netherlands)

M.D.N. Lew (Magdeleine D.N.); H.G. Schmidt (Henk)

2011-01-01

textabstractThe purposes of the present study were two-fold: first, to evaluate whether reflection journal writing was effective in promoting self-reflection and learning, and whether students become better at self-reflection if they engage continuously in reflection journal writing. To that end,

See, reflect, learn more: qualitative analysis of breaking bad news reflective narratives.

Science.gov (United States)

Karnieli-Miller, Orit; Palombo, Michal; Meitar, Dafna

2018-05-01

Breaking bad news (BBN) is a challenge that requires multiple professional competencies. BBN teaching often includes didactic and group role-playing sessions. Both are useful and important, but exclude another critical component of students' learning: day-to-day role-model observation in the clinics. Given the importance of observation and the potential benefit of reflective writing in teaching, we have incorporated reflective writing into our BBN course. The aim of this study was to enhance our understanding of the learning potential in reflective writing about BBN encounters and the ability to identify components that inhibit this learning. This was a systematic qualitative immersion/crystallization analysis of 166 randomly selected BBN narratives written by 83 senior medical students. We analysed the narratives in an iterative consensus-building process to identify the issues discussed, the lessons learned and the enhanced understanding of BBN. Having previously been unaware of, not invited to or having avoided BBN encounters, the mandatory assignment led students to search for or ask their mentors to join them in BBN encounters. Observation and reflective writing enhanced students' awareness that 'bad news' is relative and subjective, while shedding light on patients', families', physicians' and their own experiences and needs, revealing the importance of the different components of the BBN protocol. We identified diversity among the narratives and the extent of students' learning. Narrative writing provided students with an opportunity for a deliberative learning process. This led to deeper understanding of BBN encounters, of how to apply the newly taught protocol, or of the need for it. This process connected the formal and informal or hidden curricula. To maximise learning through reflective writing, students should be encouraged to write in detail about a recent observed encounter, analyse it according to the protocol, address different participants

Optical Modeling of Spectral Backscattering and Remote Sensing Reflectance From Emiliania huxleyi Blooms

Directory of Open Access Journals (Sweden)

Griet Neukermans

2018-05-01

Full Text Available In this study we develop an analytical model for spectral backscattering and ocean color remote sensing of blooms of the calcifying phytoplankton species Emiliania huxleyi. Blooms of this coccolithophore species are ubiquitous and particularly intense in temperate and subpolar ocean waters. We first present significant improvements to our previous analytical light backscattering model for E. huxleyi coccoliths and coccospheres by accounting for the elliptical shape of coccoliths and the multi-layered coccosphere architecture observed on detailed imagery of E. huxleyi liths and coccospheres. Our new model also includes a size distribution function that closely matches measured E. huxleyi size distributions. The model for spectral backscattering is then implemented in an analytical radiative transfer model to evaluate the variability of spectral remote sensing reflectance with respect to changes in the size distribution of the coccoliths and during a hypothetical E. huxleyi bloom decay event in which coccospheres shed their liths. Our modeled remote sensing reflectance spectra reproduced well the bright milky turquoise coloring of the open ocean typically associated with the final stages of E. huxleyi blooms, with peak reflectance at a wavelength of 0.49 μm. Our results also show that the magnitude of backscattering from coccoliths when attached to or freed from the coccosphere does not differ much, contrary to what is commonly assumed, and that the spectral shape of backscattering is mainly controlled by the size and morphology of the coccoliths, suggesting that they may be estimated from spectral backscattering.

Behaviour and design considerations for continuous flow closed-open-closed liquid microchannels.

Science.gov (United States)

Melin, Jessica; van der Wijngaart, Wouter; Stemme, Göran

2005-06-01

This paper introduces a method of combining open and closed microchannels in a single component in a novel way which couples the benefits of both open and closed microfluidic systems and introduces interesting on-chip microfluidic behaviour. Fluid behaviour in such a component, based on continuous pressure driven flow and surface tension, is discussed in terms of cross sectional flow behaviour, robustness, flow-pressure performance, and its application to microfluidic interfacing. The closed-open-closed microchannel possesses the versatility of upstream and downstream closed microfluidics along with open fluidic direct access. The device has the advantage of eliminating gas bubbles present upstream when these enter the open channel section. The unique behaviour of this device opens the door to applications including direct liquid sample interfacing without the need for additional and bulky sample tubing.

An Access Control Framework for Reflective Middleware

Institute of Scientific and Technical Information of China (English)

Gang Huang; Lian-Shan Sun

2008-01-01

Reflective middleware opens up the implementation details of middleware platform and applications at runtime for improving the adaptability of middleware-based systems. However, such openness brings new challenges to access control of the middleware-based systems.Some users can access the system via reflective entities, which sometimes cannot be protected by access control mechanisms of traditional middleware. To deliver high adaptability securely, reflective middleware should be equipped with proper access control mechanisms for potential access control holes induced by reflection. One reason of integrating these mechanisms in reflective middleware is that one goal of reflective middleware is to equip applications with reflection capabilities as transparent as possible. This paper studies how to design a reflective J2EE middlewarePKUAS with access control in mind. At first, a computation model of reflective system is built to identify all possible access control points induced by reflection. Then a set of access control mechanisms, including the wrapper of MBeans and a hierarchy of Java class loaders, are equipped for controlling the identified access control points. These mechanisms together with J2EE access control mechanism form the access control framework for PKUAS. The paper evaluates the security and the performance overheads of the framework in quality and quantity.

Surface characterization of selected polymer thin films by total-reflection x-ray fluorescence spectroscopy and x-ray reflectivity

International Nuclear Information System (INIS)

Innis, Vallerie Ann A.

2006-01-01

Development of available x-ray characterizations tools for grazing incidence techniques was done to be able to probe nano-size thin films. Alignment of a Philips x-ray powder diffractometer was improved to let it perform as an x-ray reflectometer. X-ray reflectometry was coupled with total-reflection x-ray fluorescence spectroscopy. Evaluation of the performance of this grazing incidence techniques was done by preparing polymer thin films of carboxymethylcellulose, carrageenan and polyvinylpyrrolidone (PVP). The thickness of the films were varied by varying the process parameters such as concentration, spin speed and spin time. Angle-dispersive total-reflection x-ray fluorescence spectroscopy profiles of three films showed film formation only in carrageenan and PVP. For both carrageenan and PVP, an increase in concentration yielded a corresponding increase in intensity of the fluorescent or scattered peaks. XRR profiles of carrageenan thin films yielded a mean value for the critical angle close to quartz substrate. Thickness measurements of the prepared carrageenan thin films showed that concentration was the main determinant for final film thickness over the other process parameters. Sulfur fluorescent intensity derived from the TXRF measurement showed a linear relationship with the measured thickness by XRR. For PVP, measured critical angle is lower than quartz. Poor adhesion of the polymer onto the substrate yielded a limited number of thickness measurements made from the XRR profiles. (Author)

Ecological Challenges for Closed Systems

Science.gov (United States)

Nelson, Mark; Dempster, William; Allen, John P.

2012-07-01

Closed ecological systems are desirable for a number of purposes. In space life support systems, material closure allows precious life-supporting resources to be kept inside and recycled. Closure in small biospheric systems facilitates detailed measurement of global ecological processes and biogeochemical cycles. Closed testbeds facilitate research topics which require isolation from the outside (e.g. genetically modified organisms; radioisotopes) so their ecological interactions and fluxes can be studied separate from interactions with the outside environment. But to achieve and maintain closure entails solving complex ecological challenges. These challenges include being able to handle faster cycling rates and accentuated daily and seasonal fluxes of critical life elements such as carbon dioxide, oxygen, water, macro- and mico-nutrients. The problems of achieving sustainability in closed systems for life support include how to handle atmospheric dynamics including trace gases, producing a complete human diet and recycling nutrients and maintaining soil fertility, the sustaining of healthy air and water and preventing the loss of crucial elements from active circulation. In biospheric facilities the challenge is also to produce analogues to natural biomes and ecosystems, studying processes of self-organization and adaptation in systems that allow specification or determination of state variables and cycles which may be followed through all interactions from atmosphere to soils. Other challenges include the dynamics and genetics of small populations, the psychological challenges for small isolated human groups and measures and options which may be necessary to ensure long-term operation of closed ecological systems.

Entry Points When Undergraduate Research Mentors Reflect on Their Role: A Qualitative Case Study

Science.gov (United States)

Wallin, Patric; Adawi, Tom

2018-01-01

Graduate students and postdoctoral researchers are increasingly taking on mentoring roles in undergraduate research (UR). There is, however, a paucity of research focusing on how they conceptualize their mentoring role. In this qualitative interview study, we identified three entry points that mentors reflect on to define their role: (1) What are…

Spectral and geometrical variation of the bidirectional reflectance distribution function of diffuse reflectance standards.

Science.gov (United States)

Ferrero, Alejandro; Rabal, Ana María; Campos, Joaquín; Pons, Alicia; Hernanz, María Luisa

2012-12-20

A study on the variation of the spectral bidirectional reflectance distribution function (BRDF) of four diffuse reflectance standards (matte ceramic, BaSO(4), Spectralon, and white Russian opal glass) is accomplished through this work. Spectral BRDF measurements were carried out and, using principal components analysis, its spectral and geometrical variation respect to a reference geometry was assessed from the experimental data. Several descriptors were defined in order to compare the spectral BRDF variation of the four materials.

Reflectance spectra of subarctic lichens

International Nuclear Information System (INIS)

Petzold, D.E.; Goward, S.N.

1988-01-01

Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the mid latitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 μm, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future. (author)

Reflectance spectra of subarctic lichens

Science.gov (United States)

Petzold, Donald E.; Goward, Samuel N.

1988-01-01

Lichens constitute a major portion of the ground cover of high latitude environments, but little has been reported concerning their in situ solar spectral reflectance properties. Knowledge of these properties is important for the interpretation of remotely sensed observations from high latitude regions, as well as in studies of high latitude ecology and energy balance climatology. The spectral reflectance of common boreal vascular plants is similar to that of vascular plants of the midlatitudes. The dominant lichens, in contrast, display variable reflectance patterns in visible wavelengths. The relative reflectance peak at 0.55 microns, common to green vegetation, is absent or indistinct in spectra of pervasive boreal forest and tundra lichens, despite the presence of chlorophyll in the inner algal cells. Lichens of the dominant genus, Cladina, display strong absorption of ultraviolet energy and short-wavelength blue light relative to their absorption in other visible wavelengths. Since the Cladinae dominate both the surface vegetation in open woodlands of the boreal forest and the low arctic tundra, their unusual spectral reflectance patterns will enable accurate monitoring of the boreal forest-tundra ecotone and detection of its vigor and movement in the future.

Clinical study of internal derangement of the temporomandibular joint with closed lock, 2

International Nuclear Information System (INIS)

Moriya, Yoshiyuki; Murakami, Ken-ichiro; Fujimura, Kazuma; Yokoyama, Tadaaki; Nose, Masahiro; Miyaki, Katsuaki; Segami, Natsuki; Iizuka, Tadahiko

1990-01-01

Fifty-three closed lock cases of internal derangement of the temporomandibular joint (TMJ) were studied on the correlation between disk configuration at MR imaging and nine clinical parameters composed of opening degree, age, clicking and locking duration, visual analogue scale of pain (VAS), pain score, jaw dysfunction score, life activity limited score, and TMJ X-ray photo findings. Disk configuration and degree of anterior disk displacement were assessed on MR imaging in closed mouth position: the antero-posterior length of disk and the distance from condyle to anterior and posterior portion of disk were measured, respectively. Duration of clicking and locking were not correlated with MR index except that there was a strong correlation between clicking duration and the distance from condyle to anterior portion of the disk at MR imaging. Opening degree was related to the disk deformity and the access of posterior portion of the disk to condyle. Disk configuration and degree of anterior disk displacement were not correlated with TMJ pain, but jaw dysfunction was related to the disk deformity and the distance from posterior portion of the disk to condyle. TMJ X-ray photo findings were not correlated with clicking duration (below 3 years), locking duration (below 30 weeks), opening degree and disk configuration at MR imaging. In evaluation of factors related to opening degree in 53 patients with closed lock by means of multiple regression analysis, age, locking and clicking duration, TMJ pain, life activity limited score were more strongly correlated to opening degree than the others. (author)

Liberating Moral Reflection

Science.gov (United States)

Horell, Harold D.

2013-01-01

The author argues that if we are to foster life-giving and liberating moral reflection, we must first liberate moral reflection from distortions; specifically, from the distorting effects of moral insensitivity, destructive moral relativism, and confusions resulting from a failure to understand the dynamics of moral reflection. The author proposes…

A study on reflection pattern of swells from the shoreline of peninsular India

Digital Repository Service at National Institute of Oceanography (India)

Anoop, T.R.; SanilKumar, V.; Johnson, G.

and tidal current on the reflected waves were examined. For the locations off the west coast of India, seasons have large impact on the reflection coefficient and were relatively less during the monsoon season due to the increase in incident wave energy...

Sputtering and reflection of self-bombardment of tungsten material

International Nuclear Information System (INIS)

Niu, Guo-jian; Li, Xiao-chun; Xu, Qian; Yang, Zhong-shi; Luo, Guang-nan

2015-01-01

In present research, the sputtering and reflection yield of self-bombardment of tungsten are investigated with the aid of molecular dynamics simulations. The source of sputtered and reflected atoms is detected by traced the original locations of sputtered and reflected atoms. Results show that for the reflected atoms no specific region exists which means cluster atoms are randomly reflected. But almost all of sputtered atoms are from a conical region under the landing point of cluster. So we can determine the sputtering yield by study the dimension of the sputtering region. Molecular dynamics shows the depth and radius of the conical are power functions of impacting energy. The effects of cluster size and temperature of target on sputtering and reflection rate are also preformed in present study. Both sputtering and reflection yield are proportion to cluster size in present cluster size, i.e. 66–2647 atoms. Higher target temperature can increase sputtering yield and deduce sputtering threshold energy, but little effect on reflection rate

Sputtering and reflection of self-bombardment of tungsten material

Energy Technology Data Exchange (ETDEWEB)

Niu, Guo-jian [University of Science and Technology of China, Hefei (China); Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Li, Xiao-chun; Xu, Qian; Yang, Zhong-shi [Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Luo, Guang-nan, E-mail: gnluo@ipp.ac.cn [University of Science and Technology of China, Hefei (China); Institute of Plasma Physics Chinese Academy of Sciences, Hefei (China); Hefei Center for Physical Science and Technology, Hefei (China); Hefei Science Center of CAS, Hefei (China)

2015-04-15

In present research, the sputtering and reflection yield of self-bombardment of tungsten are investigated with the aid of molecular dynamics simulations. The source of sputtered and reflected atoms is detected by traced the original locations of sputtered and reflected atoms. Results show that for the reflected atoms no specific region exists which means cluster atoms are randomly reflected. But almost all of sputtered atoms are from a conical region under the landing point of cluster. So we can determine the sputtering yield by study the dimension of the sputtering region. Molecular dynamics shows the depth and radius of the conical are power functions of impacting energy. The effects of cluster size and temperature of target on sputtering and reflection rate are also preformed in present study. Both sputtering and reflection yield are proportion to cluster size in present cluster size, i.e. 66–2647 atoms. Higher target temperature can increase sputtering yield and deduce sputtering threshold energy, but little effect on reflection rate.

Exploratory study of the characteristics of feedback in the reflective dialogue group given to medical students in a clinical clerkship

Directory of Open Access Journals (Sweden)

Chin-Chen Wen

2015-02-01

Full Text Available Purpose: Structured narrative reflective writing combined with guided feedback is an efficient teaching method for enhancing medical students’ reflective capacity. However, what kinds of feedback offered and reflection presented in a reflective group remain unclear. The aim of this study was to investigate the characteristics of feedback in a reflective dialogue group. Methods: Fifth-year medical students on a monthly interval rotation at the pediatric department of a medical center in eastern Taiwan during the 2012 academic year completed their reflective writing regarding patient and family psychosocial issues, and were subsequently debriefed in a 2-h group discussion session to receive feedback from a clinical tutor and peers. Content analysis was conducted to explore the characteristics of feedback and reflection presented in the reflective dialogue. The evaluative questionnaire regarding the benefits of reflection with others was administrated following the group session. Results: Forty students participated in five reflective groups and 108 psychosocial issues were discussed and identified. The tutor played an initiating role in the group discussion by providing six equal feedback types involving exploring new knowledge, initiating advanced discussion, highlighting the issues, and encouraging the students. The students provided eight types of feedback that involved a substantial deep discussion on psychosocial issues and action plans based on the complex interactive ecological network of clinical encounters. Each student attained 1.25 times the depth or breadth of reflection after receiving feedback and experienced the benefits of reflection with others. Conclusion: Through structured narrative reflective writing combined with pluralistic group discussion with a tutor and peers, the medical students had time to think deeply and broadly about psychosocial issues among patients and their family members. Facilitative feedback providing new

Student Chemical Engineering Reflective ePortfolios--ChE Student Perceptions of Learning from Reflective ePortfolio Creation

Science.gov (United States)

Cherrstrom, Catherine A.; Raisor, Cindy; Fowler, Debra

2015-01-01

Engineering educators and employers value and prioritize communication skills, but developing and assessing such skills in engineering programs is challenging. Reflective ePortfolios provide opportunities to enhance communication skills. The purpose of this three-­year qualitative case study was to investigate the use of reflective ePortfolios in…

The Relation between Science Student Teachers' Approaches to Studying and Their Attitude to Reflective Practice

Science.gov (United States)

Efe, Rifat

2018-01-01

In this study, the relation between science student teachers' approaches to studying and their attitude to reflective practice were investigated. The participants were 345 science student teachers on teacher education course during 2015-2016 academic year. The data was collected through Approaches and Study Skills Inventory for Students (ASSIST)…

Study on sodium water glass-based anti-reflective film and its application in dye-sensitized solar cells

International Nuclear Information System (INIS)

Huang, Q.Z.; Shi, J.F.; Wang, L.L.; Li, Y.J.; Zhong, L.W.; Xu, G.

2016-01-01

In this paper, anti-reflective (AR) films are prepared from sodium water glass with a simple dip-coating method. The effects of SiO_2/Na_2O molar ratio, concentration of water glass, and withdrawal speed on the anti-reflection performance of the AR films are systematically studied. The optimized AR film is further applied in dye-sensitized solar cells (DSCs). The optical properties and surface morphology of AR films are analyzed by ultraviolet-visible spectrophotometer, scanning electron microscope, and atomic force microscope. Transmittance of the glass coated with sodium water glass-based AR film is increased by 3.2% when the SiO_2/Na_2O molar ratio, concentration, and withdrawal speed equal to 3.8, 5 wt%, and 80 mm/min, respectively. Under this condition, the thickness of the AR film is 127 nm and the AR film has obvious porous structure. In addition, the power conversion efficiency of DSC coated by AR film is increased from 7.92% to 8.24%, compared with the DSC without AR film. - Highlights: • Anti-reflective films are prepared from sodium water glass. • Transmittance of anti-reflective film is increased by 3.2%. • Efficiency of dye-sensitized cell is improved by anti-reflective film.

Study on sodium water glass-based anti-reflective film and its application in dye-sensitized solar cells

Energy Technology Data Exchange (ETDEWEB)

Huang, Q.Z. [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Shi, J.F., E-mail: shijf@ms.giec.ac.cn [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China); Wang, L.L.; Li, Y.J.; Zhong, L.W. [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China); Xu, G., E-mail: xugang@ms.giec.ac.cn [Key Laboratory of Renewable Energy, Guangdong Key Laboratory of New and Renewable Energy Research and Development, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510000 (China)

2016-07-01

In this paper, anti-reflective (AR) films are prepared from sodium water glass with a simple dip-coating method. The effects of SiO{sub 2}/Na{sub 2}O molar ratio, concentration of water glass, and withdrawal speed on the anti-reflection performance of the AR films are systematically studied. The optimized AR film is further applied in dye-sensitized solar cells (DSCs). The optical properties and surface morphology of AR films are analyzed by ultraviolet-visible spectrophotometer, scanning electron microscope, and atomic force microscope. Transmittance of the glass coated with sodium water glass-based AR film is increased by 3.2% when the SiO{sub 2}/Na{sub 2}O molar ratio, concentration, and withdrawal speed equal to 3.8, 5 wt%, and 80 mm/min, respectively. Under this condition, the thickness of the AR film is 127 nm and the AR film has obvious porous structure. In addition, the power conversion efficiency of DSC coated by AR film is increased from 7.92% to 8.24%, compared with the DSC without AR film. - Highlights: • Anti-reflective films are prepared from sodium water glass. • Transmittance of anti-reflective film is increased by 3.2%. • Efficiency of dye-sensitized cell is improved by anti-reflective film.

Personal Professional Reflection as Interdisciplinary Problem

Directory of Open Access Journals (Sweden)

Rezvan Oksana

2013-08-01

Full Text Available Consideration of professional reflection as interdisciplinary problem is the necessary condition of quality analysis for personal professional becoming. Personal becoming in a profession is related to forming the necessary professional skills of a person, behaviour stereotypes which is the area of pedagogics. Reflection processes are inalienable part of self-knowledge of a person which result must lead to his self-perfection (including professional one and studying within the psychology increasingly. Thus the aim of the article is to ground the determination of professional reflection as an interdisciplinary problem in pedagogics and psychology.

Self-reflection and the brain: a theoretical review and meta-analysis of neuroimaging studies with implications for schizophrenia.

Science.gov (United States)

van der Meer, Lisette; Costafreda, Sergi; Aleman, André; David, Anthony S

2010-05-01

Several studies have investigated the neural correlates of self-reflection. In the paradigm most commonly used to address this concept, a subject is presented with trait adjectives or sentences and asked whether they describe him or her. Functional neuroimaging research has revealed a set of regions known as Cortical Midline Structures (CMS) appearing to be critically involved in self-reflection processes. Furthermore, it has been shown that patients suffering damage to the CMS, have difficulties in properly evaluating the problems they encounter and often overestimate their capacities and performance. Building on previous work, a meta-analysis of published fMRI and PET studies on self-reflection was conducted. The results showed that two areas within the medial prefrontal cortex (MPFC) are important in reflective processing, namely the ventral (v) and dorsal (d) MPFC. In this paper a model is proposed in which the vMPFC is responsible for tagging information relevant for 'self', whereas the dMPFC is responsible for evaluation and decision-making processes in self- and other-referential processing. Finally, implications of the model for schizophrenia and lack of insight are noted. (c) 2009 Elsevier Ltd. All rights reserved.

Polarized infrared reflectance study of free standing cubic GaN grown by molecular beam epitaxy

International Nuclear Information System (INIS)

Lee, S.C.; Ng, S.S.; Hassan, H. Abu; Hassan, Z.; Zainal, N.; Novikov, S.V.; Foxon, C.T.; Kent, A.J.

2014-01-01

Optical properties of free standing cubic gallium nitride grown by molecular beam epitaxy system are investigated by a polarized infrared (IR) reflectance technique. A strong reststrahlen band, which reveals the bulk-like optical phonon frequencies, is observed. Meanwhile, continuous oscillation fringes, which indicate the sample consists of two homogeneous layers with different dielectric constants, are observed in the non-reststrahlen region. By obtaining the first derivative of polarized IR reflectance spectra measured at higher angles of incidence, extra phonon resonances are identified at the edges of the reststrahlen band. The observations are verified with the theoretical results simulated based on a multi-oscillator model. - Highlights: • First time experimental studies of IR optical phonons in bulk like, cubic GaN layer. • Detection of extra phonon modes of cubic GaN by polarized IR reflectance technique. • Revelation of IR multiphonon modes of cubic GaN by first derivative numerical method. • Observation of multiphonon modes requires very high angle of incidence. • Resonance splitting effect induced by third phonon mode is a qualitative indicator

Pornography use and closeness with others in women

Directory of Open Access Journals (Sweden)

Popović Miodrag

2011-01-01

Full Text Available Introduction. Closeness/intimacy and pornography are sometimes linked and frequently presented as competing with each other. They have been the subject of some research but many issues in the area remain controversial and indeterminate. Objective. The aim of this pilot study was to establish whether female pornography users and non-users’ ratings in terms of socio-emotional closeness differed, i.e. to examine the association between pornography use and aspects of socio-emotional closeness in a non-clinical sample of females. Methods. Sixty-six females participated in the study. Their actual and ideal socioemotional closeness was measured by the Perceived Interpersonal Closeness Scale/PICS, while their pornography use was examined by the Background and Pornography Use Information Questionnaire. Potential links between the two variables and comparisons with the relevant results obtained by males are presented. Results. The results showed that there were no significant differences between self-reported female pornography users and non-users in terms of total closeness numbers and scores and also in specific socioemotional closeness with the most significant adults in their lives (i.e., partners, closest friends, mothers and fathers. Conclusion. The results confirmed that there were differences between females and males’ approaches to pornography and closeness; females had lower interest in pornography and their use of it had not been associated with higher total closeness numbers and scores. Due to the participant group’s size (N limitations, this sample was rather used for preliminary investigations that would enable some elementary insight into females’ relevant behaviours. Further investigations of pornography’s complex links with socio-emotional and sexual closeness on larger samples may allow more reliable comparisons between gender and pornography users groups.

Application of a two-region kinetic model for reflected reactors to experimental data

International Nuclear Information System (INIS)

Busch, R.D.; Spriggs, G.D.; Williams, J.G.

1996-01-01

Reflected reactors constitute one of the most important classes of nuclear reactors. Yet, during the past 50 yr, a plethora of experimental data involving reflected systems has been reported in the literature that cannot be satisfactorily explained using the open-quotes standardclose quotes (i.e., one-region) point-kinetic model. In particular, many have observed that the prompt-decay a curves obtained from Rossi-α and pulsed-neutron experiments can exhibit multiple decay modes in the vicinity near delayed critical in some types of reflected systems. When analyzed using theories based on the standard point-kinetic model, these data yielded system lifetimes that do not always agree well with the lifetimes predicted by numerical solutions of the multigroup, multidimensional diffusion or transport equations. In several cases, when the longest lived decay mode (i.e., the dominant root) was plotted as a function of reactivity, the a curve intercepted the reactivity axis at a reactivity significantly greater than 1$. Brunson dubbed this seemingly inexplicable behavior as the open-quotes dollar discrepancy.close quotes Furthermore, it has also been observed that the kinetic behavior of some reflected, fast-burst assemblies exhibits a very pronounced nonlinear relationship between reactivity and the initial inverse period for reactivity insertions > 1 $

Pipe closing device

International Nuclear Information System (INIS)

Klahn, F.C.; Nolan, J.H.; Wills, C.

1979-01-01

The closing device closes the upper end of a support tube for monitoring samples. It meshes with the upper connecting piece of the monitorung sample capsule, and loads the capsule within the bore of the support tube, so that it is fixed but can be released. The closing device consists of an interlocking component with a chamber and several ratchets which hang down. The interlocking component surrounds the actuating component for positioning the ratchets. The interlocking and actuating components are movable axially relative to each other. (DG) [de

Uses of Technology to Support Reflective Teaching Practices

Science.gov (United States)

Brent, Wayne

2010-01-01

This dissertation researched and reported on how technology was used to facilitate and inform reflective teaching practices. It also identified the characteristics of benefits and barriers in using technology for teaching and reflection. The study, descriptive in nature, was designed to determine the reflective practices of instructors and how…

Reflection on Cuboid Net with Mathematical Learning Quality

Science.gov (United States)

Sari, Atikah; Suryadi, Didi; Syaodih, Ernawulan

2017-09-01

This research aims to formulate an alternative to the reflection in mathematics learning activities related to the activities of the professionalism of teachers motivated by a desire to improve the quality of learning. This study is a qualitative study using the Didactical Design research. This study was conducted in one of the elementary schools. The data collection techniques are triangulation with the research subject is teacher 5th grade. The results of this study indicate that through deep reflection, teachers can design learning design in accordance with the conditions of the class. Also revealed that teachers have difficulty in choosing methods of learning and contextual learning media. Based on the implementation of activities of reflection and make the learning design based on the results of reflection can be concluded that the quality of learning in the class will develop.

Simulation study of the aerosol information content in OMI spectral reflectance measurements

Directory of Open Access Journals (Sweden)

B. Veihelmann

2007-06-01

Full Text Available The Ozone Monitoring Instrument (OMI is an imaging UV-VIS solar backscatter spectrometer and is designed and used primarily to retrieve trace gases like O₃ and NO₂ from the measured Earth reflectance spectrum in the UV-visible (270–500 nm. However, also aerosols are an important science target of OMI. The multi-wavelength algorithm is used to retrieve aerosol parameters from OMI spectral reflectance measurements in up to 20 wavelength bands. A Principal Component Analysis (PCA is performed to quantify the information content of OMI reflectance measurements on aerosols and to assess the capability of the multi-wavelength algorithm to discern various aerosol types. This analysis is applied to synthetic reflectance measurements for desert dust, biomass burning aerosols, and weakly absorbing anthropogenic aerosol with a variety of aerosol optical thicknesses, aerosol layer altitudes, refractive indices and size distributions. The range of aerosol parameters considered covers the natural variability of tropospheric aerosols. This theoretical analysis is performed for a large number of scenarios with various geometries and surface albedo spectra for ocean, soil and vegetation. When the surface albedo spectrum is accurately known and clouds are absent, OMI reflectance measurements have 2 to 4 degrees of freedom that can be attributed to aerosol parameters. This information content depends on the observation geometry and the surface albedo spectrum. An additional wavelength band is evaluated, that comprises the O₂-O₂ absorption band at a wavelength of 477 nm. It is found that this wavelength band adds significantly more information than any other individual band.

Closed orbit correction in the SSC

International Nuclear Information System (INIS)

Bourianoff, G.; Cole, B.; Ferede, H.; Pilat, F.

1991-01-01

Most of the techniques associated with closed orbit correction are widely known. The present paper gives a brief description of one such method and discusses the results obtained when it is applied to the SSC collider lattice. The emphasis is on features of the lattice which effect closed orbit correction and it is likely that any of the 8 methods cataloged in a cited reference would yield similar results. The global scheme described here is very robust and easy to apply. The results of three separate studies are briefly described. Typical results for the residual RMS closed orbit in the arc is calculated to be 0.65 mm with peak values of 3 mm

On the conductive properties of MgO films grown on ultrathin hexagonal close-packed Co(0001) layer

International Nuclear Information System (INIS)

Gladczuk, L.; Aleszkiewicz, M.

2013-01-01

Here we present a scanning tunneling microscopy study of electrical conductivity of (110)-oriented MgO ultrathin films grown on hexagonal close-packed Co(0001) surface by molecular beam epitaxy, being a good candidate for tunneling barrier for future-generation spintronic devices. Three-dimensional growth of the tunneling barrier, expected for compressive strains emerging at the Co/MgO interface, is demonstrated by reflection high-energy electron diffraction and atomic force microscopy. The 5 eV height of the full barrier of MgO is reached at a layer thickness of 4 nm. Thinner MgO layers exhibit randomly distributed spots of the high conductance on the tunneling current map. The current–voltage curves indicate the existence of vacancies in MgO crystal lattice, lowering the resistivity of the tunneling barrier. - Highlights: • Conductivity of MgO barrier in MgO/hexagonal close-packed-Co bilayer • Conductivity strongly varies with MgO thickness • MgO barrier exhibits randomly distributed spots of particularly high conductance • Tunneling current–voltage curves indicate the existence of vacancies in MgO lattice

Reflective writing: the student nurse's perspective on reflective writing and poetry writing.

Science.gov (United States)

Coleman, Dawn; Willis, Diane S

2015-07-01

Reflective writing is a mandatory part of nurse education but how students develop their skills and use reflection as part of their experiential learning remains relatively unknown. Understanding reflective writing in all forms from the perspective of a student nurse is therefore important. To explore the use of reflective writing and the use of poetry in pre-registered nursing students. A qualitative design was employed to explore reflective writing in pre-registered nursing students. A small university in Scotland. BSc (Hons) Adult and Mental Health Pre-registration Student Nurses. Two focus groups were conducted with 10 student nurses during March 2012. Data was analysed thematically using the framework of McCarthy (1999). Students found the process of reflective writing daunting but valued it over time. Current educational methods, such as assessing reflective accounts, often lead to the 'narrative' being watered down and the student feeling judged. Despite this, reflection made students feel responsible for their own learning and research on the topic. Some students felt the use of models of reflection constricting, whilst poetry freed up their expression allowing them to demonstrate the compassion for their patient under their care. Poetry writing gives students the opportunity for freedom of expression, personal satisfaction and a closer connection with their patients, which the more formal approach to reflective writing did not offer. There is a need for students to have a safe and supportive forum in which to express and have their experiences acknowledged without the fear of being judged. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Women's reflections and actions regarding working after breast cancer surgery - a focus group study.

Science.gov (United States)

Nilsson, M I; Olsson, M; Wennman-Larsen, A; Petersson, L-M; Alexanderson, K

2013-07-01

To better understand processes affecting return to work (RTW) after breast cancer, more knowledge from the perspective of sickness absentees is warranted. Still, research based on women's own reasoning and actions in RTW is very scarce. This study aims to elucidate how women with breast cancer reflect and act on work-related issues. Thematic analyses of data from four focus group interviews with 23 women who had had breast cancer surgery in the previous 3-13 months were carried out. The five following themes of reflections regarding RTW were identified: 'health and functioning', 'self-esteem/integrity', 'value of work', 'relationships at work', and 'social circumstances'. These reflections were associated with the three identified themes of actions taken by the women: 'to work or to be sickness absent', 'to adjust work according to own needs or not', and 'to disclose or to hide one's cancer'. There was a distinct difference between women who experienced work as a source of well-being and those who needed a respite from work. This study adds knowledge to the process of RTW after breast cancer and focuses on factors that lead the women to an active role in this process. We point to the interplay between women's own preferences, perceived competence, outer opportunities, and the actions each woman take with regard to RTW, which need to be recognized by all stakeholders involved. Furthermore, it continues to be essential to address the specific issue of disclosure in the workplace because this may be distressing for women. Copyright © 2012 John Wiley & Sons, Ltd.

An experimental study of transmission, reflection and scattering of sound in a free-jet flight simulation facility and comparison with theory

Science.gov (United States)

Ahuja, K. K.; Tester, B. J.; Tanna, H. K.; Searle, N.

1977-01-01

Acoustic time delays across a free-jet shear layer are measured and compared with predictions based on (1) ray paths refracted abruptly across a cylindrical vortex sheet and (2) ray paths traced through a more realistic diverging flow model. The close agreement between measurement and theory confirms that Snell's law provides an accurate prediction of wavefront refraction or angle changes across a diverging shear layer. Microphones are placed on calculated ray paths to determine the coherent transmission and internal reflection characteristics of the shear layer and also the scattering of sound by the shear-layer turbulence. The transmission data essentially verify the proposed, theoretical calibration factor which forms part of a computational procedure that is being developed to convert model jet data from a free-jet facility to inflight conditions.

Inflation in a closed universe

Science.gov (United States)

Ratra, Bharat

2017-11-01

To derive a power spectrum for energy density inhomogeneities in a closed universe, we study a spatially-closed inflation-modified hot big bang model whose evolutionary history is divided into three epochs: an early slowly-rolling scalar field inflation epoch and the usual radiation and nonrelativistic matter epochs. (For our purposes it is not necessary to consider a final dark energy dominated epoch.) We derive general solutions of the relativistic linear perturbation equations in each epoch. The constants of integration in the inflation epoch solutions are determined from de Sitter invariant quantum-mechanical initial conditions in the Lorentzian section of the inflating closed de Sitter space derived from Hawking's prescription that the quantum state of the universe only include field configurations that are regular on the Euclidean (de Sitter) sphere section. The constants of integration in the radiation and matter epoch solutions are determined from joining conditions derived by requiring that the linear perturbation equations remain nonsingular at the transitions between epochs. The matter epoch power spectrum of gauge-invariant energy density inhomogeneities is not a power law, and depends on spatial wave number in the way expected for a generalization to the closed model of the standard flat-space scale-invariant power spectrum. The power spectrum we derive appears to differ from a number of other closed inflation model power spectra derived assuming different (presumably non de Sitter invariant) initial conditions.

An assessment of thin cloud detection by applying bidirectional reflectance distribution function model-based background surface reflectance using Geostationary Ocean Color Imager (GOCI): A case study for South Korea

Science.gov (United States)

Kim, Hye-Won; Yeom, Jong-Min; Shin, Daegeun; Choi, Sungwon; Han, Kyung-Soo; Roujean, Jean-Louis

2017-08-01

In this study, a new assessment of thin cloud detection with the application of bidirectional reflectance distribution function (BRDF) model-based background surface reflectance was undertaken by interpreting surface spectra characterized using the Geostationary Ocean Color Imager (GOCI) over a land surface area. Unlike cloud detection over the ocean, the detection of cloud over land surfaces is difficult due to the complicated surface scattering characteristics, which vary among land surface types. Furthermore, in the case of thin clouds, in which the surface and cloud radiation are mixed, it is difficult to detect the clouds in both land and atmospheric fields. Therefore, to interpret background surface reflectance, especially underneath cloud, the semiempirical BRDF model was used to simulate surface reflectance by reflecting solar angle-dependent geostationary sensor geometry. For quantitative validation, Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data were used to make a comparison with the proposed cloud masking result. As a result, the new cloud masking scheme resulted in a high probability of detection (POD = 0.82) compared with the Moderate Resolution Imaging Spectroradiometer (MODIS) (POD = 0.808) for all cloud cases. In particular, the agreement between the CALIPSO cloud product and new GOCI cloud mask was over 94% when detecting thin cloud (e.g., altostratus and cirrus) from January 2014 to June 2015. This result is relatively high in comparison with the result from the MODIS Collection 6 cloud mask product (MYD35).

Written reflection in an eHealth intervention for adults with type 2 diabetes mellitus: a qualitative study

Directory of Open Access Journals (Sweden)

Lie SS

2018-02-01

Full Text Available Silje S Lie,1 Bjørg Karlsen,1 Christopher P Niemiec,2 Marit Graue,3 Bjørg Oftedal1 1Department of Public Health, Faculty of Health Sciences, University of Stavanger, Stavanger, Norway; 2Department of Clinical and Social Sciences in Psychology, University of Rochester, Rochester, NY, USA; 3Center for Evidence-Based Practice, Western Norway University of Applied Sciences, Bergen, Norway Background: Individuals with type 2 diabetes mellitus (T2DM are responsible for the daily decisions and actions necessary to manage their disease, which makes self-management the cornerstone of diabetes care. Many patients do not reach recommended treatment goals, and thus it is important to develop and evaluate innovative interventions that facilitate optimal motivation for adequate self-management of T2DM. Objective: The aim of the current study was to explore how adults with T2DM experience using reflection sheets to stimulate written reflection in the context of the Guided Self-Determination (GSD eHealth intervention and how written reflection might affect their motivation for self-management of T2DM. Methods: We used a qualitative design in which data were collected through individual interviews. The sample consisted of 10 patients who completed the GSD eHealth intervention, and data were analyzed using qualitative content analysis. Results: The qualitative content analysis yielded 2 main themes. We labeled the first theme as “Written reflection affects awareness and commitment in diabetes self-management”, which reflects 2 subthemes, namely, “Writing creates space and time for autonomous reflection” and “Writing influences individuals’ focus in diabetes self-management”. We labeled the second theme as “Written reflection is perceived as inapplicable in diabetes self-management”, which reflects 2 subthemes, namely, “Responding in writing is difficult” and “The timing of the writing is inappropriate”. Conclusion: Our findings

Self-Reflection, Insight, and Individual Differences in Various Language Tasks

Science.gov (United States)

Xu, Xu

2011-01-01

This study explored the relationships of self-reflection and insight with individuals' performances on various language tasks. The Self-Reflection and Insight Scale (SRIS; Grant, Franklin, & Langford, 2002) assessed individual differences in three factors: engagement in reflection, need for reflection, and insight. A high need for reflection was…

Reflective Healthcare Systems: micro-Cycle of Self-Reflection to empower users

Directory of Open Access Journals (Sweden)

Juan Jimenez Garcia

2015-02-01

Full Text Available Data collection and reflection are considered an integrated process in Personal Informatics to help users take action towards changing behaviour. Facilitating the collection and visualization of large data sets has been a major technical challenge to guarantee meaningful and effortless information to users. However this focus results in a passive involvement of users in these stages, creating distance between the user and their data, thus hindering proper understanding of people’s current behaviours. Designing for active participation may aid users in forming a closer bond to data. Going beyond the support of visualization of performance data, this paper introduces ESTHER 1.3 as an approach to facilitate active mini cycles of self-reflection (mCR by means of in-situ self-reporting mechanisms. ESTHER 1.3 is presented as an implementation of this mini cycles in the context of physical activity and knowledge workers. A field study evaluation of 23 days with 5 users shows the opportunities of the mini cycles to engage people in deeper reflection and to support them to perform better-informed actions, as well as the challenges in the implementation of mCR elements for a specific context.

Properties of interstellar dust in reflection nebulae

International Nuclear Information System (INIS)

Sellgren, K.

1988-01-01

Observations of interstellar dust in reflection nebulae are the closest analog in the interstellar medium to studies of cometary dust in our solar system. The presence of a bright star near the reflection nebula dust provides the opportunity to study both the reflection and emission characteristics of interstellar dust. At 0.1 to 1 micrometer, the reflection nebula emission is due to starlight scattered by dust. The albedo and scattering phase function of the dust is determined from observations of the scattered light. At 50 to 200 micrometers, thermal emission from the dust in equilibrium with the stellar radiation field is observed. The derived dust temperature determines the relative values of the absorption coefficient of the dust at wavelengths where the stellar energy is absorbed and at far infrared wavelengths where the absorbed energy is reradiated. These emission mechanisms directly relate to those seen in the near and mid infrared spectra of comets. In a reflection nebula the dust is observed at much larger distances from the star than in our solar system, so that the equilibrium dust temperature is 50 K rather than 300 K. Thus, in reflection nebulae, thermal emission from dust is emitted at 50 to 200 micrometer

The publishing game: reflections of an editorial team.

Science.gov (United States)

Crawford, James M; Ketcham, Catherine M; Braylan, Raul; Morel, Laurence; Terada, Naohiro; Turner, Jerrold R; Yachnis, Anthony T

2008-12-01

The close of a 5-year editorship gives opportunity to reflect on the highs and the lows of an editorship. The goal of such reflection is to assist both authors and reviewers in interacting with a biomedical journal, and to foster interest among individuals contemplating an editorship. Among the highs was the privilege of publishing high-quality original scientific work within the scope of the journal; in this instance mechanistic studies of disease. Although review articles and editorials have their reward, it is the publication of original peer-reviewed work that constitutes the true basis for advancing biomedical science. This is the heart of journal publication. Second, the editorial interaction with submitting authors in bringing their work to publication is itself highly rewarding, and can lead to longer-term collegial working relationships between editors and authors. The anonymous expert reviewers also play a key role in bringing outstanding scientific work to successful publication. Collectively, authors, editors, and reviewers constitute an important 'community of science'. Third, working together as an editorial team, especially through the weekly 'journal clubs' that a regular editorial meeting affords, is commended as a key reward of any editorial group taking on journal management. The lows included sifting through submitted manuscripts in which the rigor of science was not satisfactory, and encountering specific instances of compromised scientific integrity--fortunately rare. In both instances, the editorial commitment is to publish high-quality original science; a necessary corollary is identifying those submissions, through rigorous but fair review, which do not meet journal standards. In the end, editorship is a highly rewarding experience, and very much conducive to sustaining the wonder of science that drew us to this profession.

Methodological Reflections: Inter- ethnic Research

DEFF Research Database (Denmark)

Singla, Rashmi

2010-01-01

with both youth and the parental generation with ethnic minority background in Denmark. These reflections include implications and challenges related to researcher’s national, ethnic background and educational, professional position in encounter with   diverse ‘researched persons’ such as youth......This article reflects on the methodological and epistemological aspects of the ethical issues involved in encounters between researcher and research participants with ethnic minority background in contexts with diversity. Specific challenges involved in longitudinal research (10 - 15 years......) are also considered. The issues related to the social relevance of the research deriving from psycho political validity implying consideration of power dynamics in the personal, relational and collective domains are included. The primary basis for these reflections is a follow-up study concerning young...

Closed hierarchy of correlations in Markovian open quantum systems

International Nuclear Information System (INIS)

Žunkovič, Bojan

2014-01-01

We study the Lindblad master equation in the space of operators and provide simple criteria for closeness of the hierarchy of equations for correlations. We separately consider the time evolution of closed and open systems and show that open systems satisfying the closeness conditions are not necessarily of Gaussian type. In addition, we show that dissipation can induce the closeness of the hierarchy of correlations in interacting quantum systems. As an example we study an interacting optomechanical model, the Fermi–Hubbard model, and the Rabi model, all coupled to a fine-tuned Markovian environment and obtain exact analytic expressions for the time evolution of two-point correlations. (paper)

Environmental Rehabilitation of Closed Mines. A Chase Study on Romania

Directory of Open Access Journals (Sweden)

Bianca COBÂRZAN

2008-02-01

Full Text Available The present article attempts to analyze methods that can be used to restore a former coal mining site to a condition that is well integrated into its surroundings and that recovers the abandoned and contaminated land and renders its value to the community. The key concept that guides the present paper is that the coal mining is just a temporary land use and that the cost of cleaning the mining site should be an operating expense that has to be included in the budget of a coal mine company starting with the first year of operation. The coal mining industry in Romania is presented as a case study to emphasize the effects that closed coal mines have on communities where they are located and, based on the methods that are successfully used to solve similar problems, recommendations are formulated to improve the environmental rehabilitation of the mining sites.

Study on Reflected Shock Wave/Boundary Layer Interaction in a Shock Tube

Energy Technology Data Exchange (ETDEWEB)

Kim, Dong Wook; Kim, Tae Ho; Kim, Heuy Dong [Andong Nat’l Univ., Andong (Korea, Republic of)

2017-07-15

The interaction between a shock wave and a boundary layer causes boundary layer separation, shock train, and in some cases, strong unsteadiness in the flow field. Such a situation is also observed in a shock tube, where the reflected shock wave interacts with the unsteady boundary layer. However, only a few studies have been conducted to investigate the shock train phenomenon in a shock tube. In the present study, numerical studies were conducted using the two-dimensional axisymmetric domain of a shock tube, and compressible Navier-Stokes equations were solved to clarify the flow characteristics of shock train phenomenon inside a shock tube. A detailed wave diagram was developed based on the present computational results, which were validated with existing experimental data.

How Reflective Is the Academic Essay?

Science.gov (United States)

Maclellan, Effie

2004-01-01

The purpose of this study was to examine the extent of reflection in academic essays. Forty essays, all previously deemed to be of merit quality, were analysed in terms of three elements of reflection--how the educational issue is conceptualized; what the issue means for practice; and how practice might be changed to resolve the problematic. Each…

Reflection as Self-Assessment

Science.gov (United States)

Pappas, Marjorie L.

2010-01-01

In this article, the author discusses how reflection can be used as self-assessment. Reflection involves not only thinking about a learning experience, but also questioning parts of the experience. Reflection is thinking about what one knows from the learning experience, what one might do differently the next time. Reflection is wondering about…

Analysis of contaminants on electronic components by reflectance FTIR spectroscopy

International Nuclear Information System (INIS)

Griffith, G.W.

1982-09-01

The analysis of electronic component contaminants by infrared spectroscopy is often a difficult process. Most of the contaminants are very small, which necessitates the use of microsampling techniques. Beam condensers will provide the required sensitivity but most require that the sample be removed from the substrate before analysis. Since it can be difficult and time consuming, it is usually an undesirable approach. Micro ATR work can also be exasperating, due to the difficulty of positioning the sample at the correct place under the ATR plate in order to record a spectrum. This paper describes a modified reflection beam condensor which has been adapted to a Nicolet 7199 FTIR. The sample beam is directed onto the sample surface and reflected from the substrate back to the detector. A micropositioning XYZ stage and a close-focusing telescope are used to position the contaminant directly under the infrared beam. It is possible to analyze contaminants on 1 mm wide leads surrounded by an epoxy matrix using this device. Typical spectra of contaminants found on small circuit boards are included

Angular dependance of spectral reflection for different materials

Science.gov (United States)

Kiefer, Pascal M.

2017-10-01

Parameters like the sun angle as well as the measurement angle mostly are not taken into account when simulating because their influence on the reflectivity is weak. Therefore the impact of a changing measurement and illumination angle on the reflectivity is investigated. Furthermore the impact of humidity and chlorophyll in the scenery is studied by analyzing reflectance spectra of different vegetative background areas. It is shown that the measurement as well as the illumination angle has an important influence on the absolute reflection values which raises the importance of measurements of the bidirectional reflectance distribution function (BRDF).

Tensions between opening up and closing down moments in transdisciplinary water research

Science.gov (United States)

Krueger, Tobias; Maynard, Carly; Carr, Gemma; Bruns, Antje; Mueller, Eva; Lane, Stuart

2016-04-01

Research on water is carried out by many disciplines that do not really talk to each other much, despite critical interactions of multiple social and biophysical processes in shaping how much and what kind of water is where, at what time and for whom. What is more, water has meaning to more than those who are scientists. And scientists are not so removed from the things they study as one might commonly believe. All these observations call for a transdisciplinary research agenda that brings together different scientific disciplines with the knowledge that other groups in society hold and that tries to be aware of its own limitations. The transdisciplinary perspective is especially pertinent to the scientific decade 2013-2022 of the International Association of Hydrological Sciences (IAHS) on change in hydrology and society, 'Panta Rhei,' for a balanced conceptualization and study of human-water relations. Transdisciplinarity is inherently about opening up traditional modes of knowledge production; in terms of framing the research problem, the methodology and the knowledge that is considered permissible. This should open up the range of options for management intervention, too. While decisions on how to intervene will inevitably close down the issue periodically, the point here is to leave alternative routes of action open long enough, or reopen them again, so as to counter unsustainable and inequitable path-dependencies and lock-ins. However, opening up efforts are frequently in conflict with factors that work to close down knowledge production. Among those are framings, path-dependencies, vested interests, researchers' positionalities, power, and scale. In this presentation, based on Krueger et al. (2016), we will reflect on the tensions between opening up and closing down moments in transdisciplinary water research and draw important practical lessons. References Krueger, T., Maynard, C.M., Carr, G., Bruns, A., Mueller, E.N. and Lane, S.N. (forthcoming in 2016) A

Self-Reflection

DEFF Research Database (Denmark)

Fausing, Bent

2016-01-01

will take a look at the establishing of the modern self and possibilities of self-reflection, too. My examples will be from the so-called dark-selfies and from a new selfie form, which merge the present with the previous progressing into the future. I will discuss the media reflections as loos and/or gain...

Personal Reflections

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education. Personal Reflections. Articles in Resonance – Journal of Science Education. Volume 6 Issue 3 March 2001 pp 90-93 Personal Reflections. Why did I opt for Career in Science? Jayant V Narlikar · More Details Fulltext PDF. Volume 9 Issue 8 August 2004 pp 89-89 ...

Neutron reflectivity study of critical adsorption. Application to the understanding of environmental mechanisms

International Nuclear Information System (INIS)

Jestin, Jacques

2001-01-01

This study is within the scope of fundamental knowledge transfer to a field case-study, i.e. the understanding of the adsorption properties of binary mixtures against a wall in the case of soil pollution by liquid hydrocarbons. From the theoretical study of critical adsorption, which has been well described in the literature, we carried out experiments on model systems by using neutron techniques. Neutron reflectivity was then applied to the liquid-vapor interface of three different binary mixtures: perfluorohexane-hexane, deuterated methanol-cyclohexane and methanol-deuterated cyclohexane. The experimental data were analysed according to the theoretical prediction of Fisher and De Gennes, along with Liu and Fisher that suggested a power law decrease of the concentration profile (with an exponent equal to 0.52) followed by an exponential function. The characteristic exponent and the amplitude ratios for the methanol-cyclohexane mixtures were found fitted well with theoretical values for the three systems. Only the perfluorohexane-hexane mixture exhibited a particular behavior in the adsorption process that affected the power law amplitude value. This step allowed us to study non critical adsorption and to apply neutrons techniques, e.g. reflectivity and small angles neutrons scattering, to a water-2,5 dimethylpyridine mixture against silica, which is a model system for soils polluted by water/hydrocarbon mixtures. These experiments highlighted new experimental difficulties, which were not fully solved over this study, together with some problems in the analysis that would require specific modelling. Nevertheless, this study shows the capabilities of neutrons techniques to investigate some environmental mechanisms. Moreover, some of the results reported here can be used as a basis for future experiments. (author)

School Closings in Philadelphia

Science.gov (United States)

Jack, James; Sludden, John

2013-01-01

In 2012, the School District of Philadelphia closed six schools. In 2013, it closed 24. The closure of 30 schools has occurred amid a financial crisis, headlined by the district's $1.35 billion deficit. School closures are one piece of the district's plan to cut expenditures and close its budget gap. The closures are also intended to make…

X-ray specular reflection and fluorescence study of nano-films

International Nuclear Information System (INIS)

Zheludeva, S.; Novikova, N.

2001-01-01

The techniques that combine the advantages of high-resolution structure sensitive x-ray methods with spectroscopic selectivity of data obtained are shown to be extremely promising for characterization of organic and inorganic nano films and nano structures. Fluorescence yield angular dependences exited by complicated evanescent wave / x-ray standing wave pattern at total reflection and glancing incidence can be used to detect structure position of different ions in organic systems and alien interfacial layers in inorganic multilayers;, to get information about interdiffusion at the interfaces of Langmuir- Blodgett (L-B) films and artificial inorganic - x-ray mirrors; to study ion permeation through L-B nano structures - models of biomembrans; to obtain nano - film thickness and density; to get precisely the parameters of small d-space multilayer mirrors, ets

Polarized neutron reflectivity and scattering studies of magnetic heterostructures

International Nuclear Information System (INIS)

Zabel, H; Theis-Broehl, K

2003-01-01

The current interest in the magnetism of ultrathin films and multilayers is driven by their manifold applications in the magneto-and spin-electronic areas, for instance as magnetic field sensors or as information storage devices. In this regard, there is a large interest in exploring spin structures and spin disorder at the interface of magnetic heterostructures, to investigate magnetic domains in thin films and superlattices, and to understand remagnetization processes of various laterally shaped magnetic nanostructures. Traditionally neutron scattering has played a dominant role in the determination of spin structures, phase transitions and magnetic excitations in bulk materials. Today, its potential for the investigation of thin magnetic films has to be redefined. Polarized neutron reflectivity (PNR) at small wavevectors can provide precise information on the magnetic field distribution parallel to the film plane and on layer resolved magnetization vectors. In addition, PNR is not only sensitive to structural interface roughness but also to the magnetic roughness. Furthermore, magnetic hysteresis measurements from polarized small angle Bragg reflections allows us to filter out correlation effects during magnetization reversals of magnetic stripes and islands. An overview is provided on most recent PNR investigations of magnetic heterostructures

Hygrothermal degradation of (3-glycidoxypropyl)trimethoxysilane films studied by neutron and X-ray reflectivity and attenuated total reflection infrared spectroscopy

International Nuclear Information System (INIS)

Tallant, David Robert; Garcia, Manuel Joseph; Majewski, Jaroslaw; Kent, Michael Stuart; Yim, Hyun

2005-01-01

Thin films of organosilanes have great technological importance in the areas of adhesion promotion, durability, and corrosion resistance. However, it is well-known that water can degrade organosilane films, particularly at elevated temperatures. In this work, X-ray and neutron reflectivity (XR and NR) were combined with attenuated total reflection infrared (ATR-IR) spectroscopy to study the chemical and structural changes within thin films of (3-glycidoxypropyl)trimethoxysilane (GPS) after exposure for various periods of time to air saturated with either D 2 O or H 2 O at 80 C. For NR and XR, ultrathin (∼100 (angstrom)) films were prepared by spin-coating. Both D 2 O and H 2 O provide neutron scattering contrast with GPS. Variations in the neutron scattering length density (SLD) profiles (a function of mass density and atomic composition) with conditioning time were measured after drying the samples out and also swelled with H 2 O or D 2 O vapor at room temperature. For samples that were dried out prior to measurement, little or no change was observed for H 2 O conditioning up to 3.5 days, but large changes were observed after 30 days of conditioning. The range of conditioning time for this structural change was narrowed to between 4 and 10 days with XR. The SLD profiles indicated that the top portion of the GPS film was transformed into a thick low-density layer after conditioning, but the bottom portion showed little structural change. A previous NR study of as-prepared GPS films involving swelling with deuterated nitrobenzene showed that the central portion of the film has much lower cross-link density than the region nearest the substrate. The present data show that the central portion also swells to a much greater extent with water and hydrolyzes more rapidly. The chemical degradation mechanism was identified by IR as hydrolysis of siloxane bonds. For ATR-IR, GPS films were prepared by dip-coating, which resulted in a greater and more variable thickness than

A novice researcher's reflection on recruiting participants for qualitative research.

Science.gov (United States)

Marks, Anne; Wilkes, Lesley; Blythe, Stacy; Griffiths, Rhonda

2017-09-19

This paper is a reflection by a PhD candidate on her qualitative study involving parents, diabetes educators and school teachers who were caring for a child with type 1 diabetes using intensive insulin therapy in primary school. To reflect on a novice researcher's experience of recruiting research participants from community, health and education settings in Australia. Participants were successfully recruited for the study using internet communication tools: Facebook support groups; the Australian Diabetes Educators Association (ADEA) e-newsletter; and emails sent to school principals. These methods were successful as Facebook and online support groups are popular, the study topic was of interest, the ADEA has many members, and numerous emails were sent to schools. Potential barriers to recruitment were a lack of access to those who did not use Facebook or the internet, gatekeepers, the high workloads of diabetes educators and teachers, and the time needed to obtain ethics approval and send a large number of emails to schools. Internet communication tools were successful in recruiting participants from community, health and education settings. However, different approaches were required for each type of participant. Lessons learned from this experience were: the importance of taking time to plan recruitment, including an in-depth understanding of potential participants and recruitment tools, the benefit of being an insider, and the need to work closely with gatekeepers. An understanding of recruitment is essential for ensuring access to appropriate participants and timely collection of data. The experience of the novice researcher may provide insight to others planning to use internet communication tools for recruitment. ©2012 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.

Study of the oxidation of uranium by external and diffuse reflectance FTIR spectroscopy using remote-sensing and evacuable cell techniques

Science.gov (United States)

Powell, G. L.; Dobbins, A.; Cristy, S. S.; Cliff, T. L.; Meyer, H. M., III; Lucania, J.; Milosevic, Milan

1994-01-01

This report describes the application of reflectance FTIR spectroscopy to the measurement of the oxidation rate of uranium by environmental gases near room temperature. It also describes very efficient evacuable cells designed for 75 degree(s) external reflectance with polarized light and for diffuse reflectance using mid-infrared FTIR spectroscopy. These cells, along with functionally similar remote sensing accessories, have been applied to the study of the oxidation of uranium metal in air, oxygen, and water vapor by precisely measuring the 575 cm-1 band of UO2 and other properties of the corrosion film such as absorbed water and reflective losses caused by film degradation related to pitting or nucleation phenomena.

Specific features of diffuse reflection of human face skin for laser and non-laser sources of visible and near-IR light

International Nuclear Information System (INIS)

Dolotov, L E; Sinichkin, Yu P; Tuchin, Valerii V; Al'tshuler, G B; Yaroslavskii, I V

2011-01-01

The specific features of diffuse reflection from different areas of human face skin for laser and non-laser sources of visible and near-IR light have been investigated to localise the closed-eye (eyelid) region. In the visible spectral range the reflection from the eyelid skin surface can be differentiated by measuring the slope of the spectral dependence of the effective optical density of skin in the wavelength range from 650 to 700nm. In the near-IR spectral range the reflectances of the skin surface at certain wavelengths, normalised to the forehead skin reflectance, can be used as a criterion for differentiating the eyelid skin. In this case, a maximum discrimination is obtained when measuring the skin reflectances at laser wavelengths of 1310 and 1470nm, which correspond to the spectral ranges of maximum and minimum water absorption. (optical technologies in biophysics and medicine)

Reflectance, absorbance and transmittance spectra of bermudagrass and manilagrass turfgrass canopies.

Directory of Open Access Journals (Sweden)

Marco Volterrani

Full Text Available Leaves act as a primary organ for the interception of solar radiation and their spatial arrangement determines how the plant canopy interacts with light. Many studies have been carried out on the penetration of radiation into crops however to date, few results are available on turfgrasses, mainly due to the difficulties of introducing sensors into the turf without disturbing the natural position of the leaves. In the present research two warm season turfgrasses, hybrid bermudagrass (Cynodon dactylon × transvaalensis 'Patriot' and manilagrass (Zoysia matrella 'Zeon', were studied. The aim was to describe their canopy architecture grown with minimal disturbance to the natural arrangement of the leaves and stems, and to determine the potential effects of canopy architecture on light penetration and reflectance. Radiometric measurements were carried out at eight different profile levels of turfgrasses that were up to 12 cm tall. A LI-COR 1800 spectroradiometer with an optical fiber cable and a 7 mm diameter sensor was used. Measurements were carried out in the 390-1100 nm region at 5 nm intervals. The LAI value was higher for the manilagrass (9.0 than for the hybrid bermudagrass (5.6. The transmitted radiation was found to be closely dependent on downward cumulative LAI. Despite a more upright habit (mean insertion angle of 22.4° ±3.4, Zoysia matrella showed a higher NIR reflectance compared to Cdxt, which has a horizontal leaf arrangement (mean insertion angle 62.1° ± 9.6. The species studied showed substantial differences both in terms of phytometric characteristics and in the capacity to attenuate solar radiation.

A Method of Retrieving BRDF from Surface-Reflected Radiance Using Decoupling of Atmospheric Radiative Transfer and Surface Reflection

Directory of Open Access Journals (Sweden)

Alexander Radkevich

2018-04-01

Full Text Available Bi-directional reflection distribution function (BRDF defines anisotropy of the surface reflection. It is required to specify the boundary condition for radiative transfer (RT modeling used in aerosol retrievals, cloud retrievals, atmospheric modeling, and other applications. Ground based measurements of reflected radiance draw increasing attention as a source of information about anisotropy of surface reflection. Derivation of BRDF from surface radiance requires atmospheric correction. This study develops a new method of retrieving BRDF on its whole domain, making it immediately suitable for further atmospheric RT modeling applications. The method is based on the integral equation relating surface-reflected radiance, BRDF, and solutions of two auxiliary atmosphere-only RT problems. The method requires kernel-based BRDF. The weights of the kernels are obtained with a quickly converging iterative procedure. RT modeling has to be done only one time before the start of iterative process.

Closing the loop.

Science.gov (United States)

Dassau, E; Atlas, E; Phillip, M

2010-02-01

The dream of closing the loop is actually the dream of creating an artificial pancreas and freeing the patients from being involved with the care of their own diabetes. Insulin-dependent diabetes (type 1) is a chronic incurable disease which requires constant therapy without the possibility of any 'holidays' or insulin-free days. It means that patients have to inject insulin every day of their life, several times per day, and in order to do it safely they also have to measure their blood glucose levels several times per day. Patients need to plan their meals, their physical activities and their insulin regime - there is only very small room for spontaneous activities. This is why the desire for an artificial pancreas is so strong despite the fact that it will not cure the diabetic patients. Attempts to develop a closed-loop system started in the 1960s but never got to a clinical practical stage of development. In recent years the availability of continuous glucose sensors revived those efforts and stimulated the clinician and researchers to believe that closing the loop might be possible nowadays. Many papers have been published over the years describing several different ideas on how to close the loop. Most of the suggested systems have a sensing arm that measures the blood glucose repeatedly or continuously, an insulin delivery arm that injects insulin upon command and a computer that makes the decisions of when and how much insulin to deliver. The differences between the various published systems in the literature are mainly in their control algorithms. However, there are also differences related to the method and site of glucose measurement and insulin delivery. SC glucose measurements and insulin delivery are the most studied option but other combinations of insulin measurements and glucose delivery including intravascular and intraperitoneal (IP) are explored. We tried to select recent publications that we believe had influenced and inspired people interested

STUDY ON SHADOW EFFECTS OF VARIOUS FEATURES ON CLOSE RANGE THERMAL IMAGES

Directory of Open Access Journals (Sweden)

C. L. Liao

2012-07-01

Full Text Available Thermal infrared data become more popular in remote sensing investigation, for it could be acquired both in day and night. The change of temperature has special characteristic in natural environment, so the thermal infrared images could be used in monitoring volcanic landform, the urban development, and disaster prevention. Heat shadow is formed by reflecting radiating capacity which followed the objects. Because of poor spatial resolution of thermal infrared images in satellite sensor, shadow effects were usually ignored. This research focus on discussing the shadow effects of various features, which include metals and nonmetallic materials. An area-based thermal sensor, FLIR-T360 was selected to acquire thermal images. Various features with different emissivity were chosen as reflective surface to obtain thermal shadow in normal atmospheric temperature. Experiments found that the shadow effects depend on the distance between sensors and features, depression angle, object temperature and emissivity of reflective surface. The causes of shadow effects have been altered in the experiment for analyzing the variance in thermal infrared images. The result shows that there were quite different impacts by shadow effects between metals and nonmetallic materials. The further research would be produced a math model to describe the shadow effects of different features in the future work.

Virtual grasping: closed-loop force control using electrotactile feedback.

Science.gov (United States)

Jorgovanovic, Nikola; Dosen, Strahinja; Djozic, Damir J; Krajoski, Goran; Farina, Dario

2014-01-01

Closing the control loop by providing somatosensory feedback to the user of a prosthesis is a well-known, long standing challenge in the field of prosthetics. Various approaches have been investigated for feedback restoration, ranging from direct neural stimulation to noninvasive sensory substitution methods. Although there are many studies presenting closed-loop systems, only a few of them objectively evaluated the closed-loop performance, mostly using vibrotactile stimulation. Importantly, the conclusions about the utility of the feedback were partly contradictory. The goal of the current study was to systematically investigate the capability of human subjects to control grasping force in closed loop using electrotactile feedback. We have developed a realistic experimental setup for virtual grasping, which operated in real time, included a set of real life objects, as well as a graphical and dynamical model of the prosthesis. We have used the setup to test 10 healthy, able bodied subjects to investigate the role of training, feedback and feedforward control, robustness of the closed loop, and the ability of the human subjects to generalize the control to previously "unseen" objects. Overall, the outcomes of this study are very optimistic with regard to the benefits of feedback and reveal various, practically relevant, aspects of closed-loop control.