Teachers as Secondary Players: Involvement in Field Trips to Natural Environments
NASA Astrophysics Data System (ADS)
Alon, Nirit Lavie; Tal, Tali
2017-08-01
This study focused on field trips to natural environments where the teacher plays a secondary role alongside a professional guide. We investigated teachers' and field trip guides' views of the teacher's role, the teacher's actual function on the field trip, and the relationship between them. We observed field trips, interviewed teachers and guides, and administered questionnaires. We found different levels of teacher involvement, ranging from mainly supervising and giving technical help, to high involvement especially in the cognitive domain and sometimes in the social domain. Analysis of students' self-reported outcomes showed that the more students believe their teachers are involved, the higher the self-reported learning outcomes.
Dynamics of polymers: A mean-field theory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fredrickson, Glenn H.; Materials Research Laboratory, University of California, Santa Barbara, California 93106; Department of Materials, University of California, Santa Barbara, California 93106
2014-02-28
We derive a general mean-field theory of inhomogeneous polymer dynamics; a theory whose form has been speculated and widely applied, but not heretofore derived. Our approach involves a functional integral representation of a Martin-Siggia-Rose (MSR) type description of the exact many-chain dynamics. A saddle point approximation to the generating functional, involving conditions where the MSR action is stationary with respect to a collective density field ρ and a conjugate MSR response field ϕ, produces the desired dynamical mean-field theory. Besides clarifying the proper structure of mean-field theory out of equilibrium, our results have implications for numerical studies of polymer dynamicsmore » involving hybrid particle-field simulation techniques such as the single-chain in mean-field method.« less
Field Research Studying Whales in an Undergraduate Animal Behavior Laboratory
ERIC Educational Resources Information Center
MacLaren, R. David; Schulte, Dianna; Kennedy, Jen
2012-01-01
This work describes a new field research laboratory in an undergraduate animal behavior course involving the study of whale behavior, ecology and conservation in partnership with a non-profit research organization--the Blue Ocean Society for Marine Conservation (BOS). The project involves two weeks of training and five weekend trips on whale watch…
Kriz, J; Baues, C; Engenhart-Cabillic, R; Haverkamp, U; Herfarth, K; Lukas, P; Schmidberger, H; Marnitz-Schulze, S; Fuchs, M; Engert, A; Eich, H T
2017-02-01
Field design changed substantially from extended-field RT (EF-RT) to involved-field RT (IF-RT) and now to involved-node RT (IN-RT) and involved-site RT (IS-RT) as well as treatment techniques in radiotherapy (RT) of Hodgkin's lymphoma (HL). The purpose of this article is to demonstrate the establishment of a quality assurance program (QAP) including modern RT techniques and field designs within the German Hodgkin Study Group (GHSG). In the era of modern conformal RT, this QAP had to be fundamentally adapted and a new evaluation process has been intensively discussed by the radiotherapeutic expert panel of the GHSG. The expert panel developed guidelines and criteria to analyse "modern" field designs and treatment techniques. This work is based on a dataset of 11 patients treated within the sixth study generation (HD16-17). To develop a QAP of "modern RT", the expert panel defined criteria for analysing current RT procedures. The consensus of a modified QAP in ongoing and future trials is presented. With this schedule, the QAP of the GHSG could serve as a model for other study groups.
Using Case Studies to Enrich Field Experience.
ERIC Educational Resources Information Center
Florio-Ruane, Susan; Clark, Christopher M.
1990-01-01
This paper discusses the use of field experience in teacher education and how it can be augmented by phenomenological case studies. It summarizes a particular case study involving three teacher education classes, noting that reflective analysis of cases can prepare students to observe in the field. (SM)
MICROFLORA INVOLVED IN PHYTOREMEDIATION OF POLYAROMATIC HYDROCARBONS
This research was accomplished by conducting a series of integrated studies starting with field work at contaminated sites, followed by laboratory studies based on the field work, and concluded with development of preliminary molecular monitoring methods tested on field sam...
Studies of electromagnetic ion cyclotron waves using AMPTE/CCE and Dynamics Explorer
NASA Technical Reports Server (NTRS)
Erlandson, Robert E.
1993-01-01
The principal activity during the past six months has involved the analysis of ion cyclotron waves recorded from DE-2 using the magnetic field experiment and electric field experiment. The results of this study have been published in the Geophysical Research Letters (GRL). The primary finding of this paper is that ion cyclotron waves were found to heat electrons, as observed in the DE-2 Langmuir probe data, through a Landau damping process. A second activity, which was started during the last six months, involves the study of large amplitude approximately one Hz electric and magnetic field oscillations recorded in the nightside auroral zone at substorm onset. Work is under way to determine the properties of these waves and investigate any association these waves may have with the substorm initiation process. A third activity under way involves a comprehensive study of ion cyclotron waves recorded at ionospheric altitudes by DE-2. This study will be an extension of the work reported in the GRL paper and will involve a larger sampling of wave events. This paper will focus on wave properties at ionospheric altitudes. A fourth activity involves a more in-depth analysis of the acceleration mechanisms and the resulting electron distributions based on the observations presented in the GRL paper.
A study of accidents involving highway bridges.
DOT National Transportation Integrated Search
1971-01-01
Accident reports, field evaluations, state police and highway engineer questionnaire replies, and other data sources were used to conduct a general study of accidents involving highway bridges in Virginia. The bridges included in the study were divid...
The promises of big data and small data for travel behavior (aka human mobility) analysis.
Chen, Cynthia; Ma, Jingtao; Susilo, Yusak; Liu, Yu; Wang, Menglin
2016-07-01
The last decade has witnessed very active development in two broad, but separate fields, both involving understanding and modeling of how individuals move in time and space (hereafter called "travel behavior analysis" or "human mobility analysis"). One field comprises transportation researchers who have been working in the field for decades and the other involves new comers from a wide range of disciplines, but primarily computer scientists and physicists. Researchers in these two fields work with different datasets, apply different methodologies, and answer different but overlapping questions. It is our view that there is much, hidden synergy between the two fields that needs to be brought out. It is thus the purpose of this paper to introduce datasets, concepts, knowledge and methods used in these two fields, and most importantly raise cross-discipline ideas for conversations and collaborations between the two. It is our hope that this paper will stimulate many future cross-cutting studies that involve researchers from both fields.
The promises of big data and small data for travel behavior (aka human mobility) analysis
Chen, Cynthia; Ma, Jingtao; Susilo, Yusak; Liu, Yu; Wang, Menglin
2016-01-01
The last decade has witnessed very active development in two broad, but separate fields, both involving understanding and modeling of how individuals move in time and space (hereafter called “travel behavior analysis” or “human mobility analysis”). One field comprises transportation researchers who have been working in the field for decades and the other involves new comers from a wide range of disciplines, but primarily computer scientists and physicists. Researchers in these two fields work with different datasets, apply different methodologies, and answer different but overlapping questions. It is our view that there is much, hidden synergy between the two fields that needs to be brought out. It is thus the purpose of this paper to introduce datasets, concepts, knowledge and methods used in these two fields, and most importantly raise cross-discipline ideas for conversations and collaborations between the two. It is our hope that this paper will stimulate many future cross-cutting studies that involve researchers from both fields. PMID:27182125
ERIC Educational Resources Information Center
Gao, Fang; Ng, Jacky Chi Kit
2017-01-01
Capital-embedded parental involvement in education is essential in enhancing university enrolment and maximising the educational potentials for equality and excellence. Previous studies in this field have mainly utilised Perna's (2000, 2006) model, which defines parental involvement as social capital and identifies the additive influences of…
ERIC Educational Resources Information Center
Bajaj, Dev Raj
This study assessed the personality traits of Oklahoma field extension personnel as related to certain professional and social attributes and to job involvement. A special background questionnaire, a job involvement inventory, and a true false test called the California Psychological Inventory (CPI) were administered to 77 county extension…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-11-20
... Activities; Proposed Collection; Comment Request: Generic Clearance for Cognitive, Pilot and Field Studies...) Title of the Form/Collection: BJS Generic Clearance for Cognitive, Pilot, and Field Test Studies. (3... respondents will be involved in exploratory, field test, pilot, cognitive, and focus group work conducted...
Evaluating Sound Field Amplification Technology in New Brunswick Schools
ERIC Educational Resources Information Center
Rubin, Rhonda; Aquino-Russell, Catherine; Flagg-Williams, Joan
2007-01-01
(Purpose) The purpose of this study was to investigate the effects of classroom sound field amplification on communication in kindergarten through grade 3 classrooms. (Methodology) Sixty classrooms were involved in the study; half of the classrooms were provided with sound field amplification. The flow of communication was measured through…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meinke, Rainer B.; Goodzeit, Carl L.; Ball, Millicent J.
This research project advanced the development of reliable, cost-effective arrays of superconducting quadrupole magnets for use in multi-beam inertial fusion accelerators. The field in each array cell must be identical and meet stringent requirements for field quality and strength. An optimized compact array design using flat double-layer pancake coils was developed. Analytical studies of edge termination methods showed that it is feasible to meet the requirements for field uniformity in all cells and elimination of stray external field in several ways: active methods that involve placement of field compensating coils on the periphery of the array or a passive methodmore » that involves use of iron shielding.« less
Teachers as Secondary Players: Involvement in Field Trips to Natural Environments
ERIC Educational Resources Information Center
Alon, Nirit Lavie; Tal, Tali
2017-01-01
This study focused on field trips to natural environments where the teacher plays a secondary role alongside a professional guide. We investigated teachers' and field trip guides' views of the teacher's role, the teacher's actual function on the field trip, and the relationship between them. We observed field trips, interviewed teachers and…
Field Evaluation of the Pedostructure-Based Model (Kamel®)
USDA-ARS?s Scientific Manuscript database
This study involves a field evaluation of the pedostructure-based model Kamel and comparisons between Kamel and the Hydrus-1D model for predicting profile soil moisture. This paper also presents a sensitivity analysis of Kamel with an evaluation field site used as the base scenario. The field site u...
ERIC Educational Resources Information Center
Scott, Graham; Churchill, Helen; Grassam, Matthew; Scott, Lisa
2012-01-01
There is a need to evaluate the benefits to children of integrated classroom and field-based learning. In this article, we describe a case study that involves children in the production of a field guide: an authentic task which integrates learner autonomy and open enquiry with field work, information and communication technologies (ICT) and…
RECRUITMENT AND FIELD SAMPLING IN THE CTEPP NORTH CAROLINA AND OHIO FIELD STUDIES
Recruiting study participants is always a challenge for researchers. It is more of a challenge when researchers have to recruit participants for a study involving intrusive, burdensome data collection activities. In this presentation, we describe our recruitment strategies and ...
ERIC Educational Resources Information Center
Jivraj, Jamil; Sacrey, Lori-Ann; Newton, Amanda; Nicholas, David; Zwaigenbaum, Lonnie
2014-01-01
Participatory research aims to increase the relevance and broaden the implementation of health research by involving those affected by the outcomes of health studies. Few studies within the field of neurodevelopmental disorders, particularly autism spectrum disorders, have involved autistic individuals as partners. This study sought to identify…
41 CFR 102-5.80 - What are some examples of positions that may involve field work?
Code of Federal Regulations, 2010 CFR
2010-07-01
... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...
41 CFR 102-5.80 - What are some examples of positions that may involve field work?
Code of Federal Regulations, 2013 CFR
2013-07-01
... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...
41 CFR 102-5.80 - What are some examples of positions that may involve field work?
Code of Federal Regulations, 2012 CFR
2012-01-01
... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...
41 CFR 102-5.80 - What are some examples of positions that may involve field work?
Code of Federal Regulations, 2011 CFR
2011-01-01
... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...
41 CFR 102-5.80 - What are some examples of positions that may involve field work?
Code of Federal Regulations, 2014 CFR
2014-01-01
... of positions that may involve field work? 102-5.80 Section 102-5.80 Public Contracts and Property...-HOME-TO-WORK TRANSPORTATION Authorizing Home-to-Work Transportation § 102-5.80 What are some examples of positions that may involve field work? Examples of positions that may involve field work include...
Nursery practices, seedling sizes, and field performance.
William I. Stein
1988-01-01
Highlights are presented from a large cooperative study to determine the combined effects of nursery cultural practices on the initial size and subsequent field performance of 2+0 Douglas-fir seedlings. The study involved seven sources of stock produced in three different nurseries and field plantings made over 3 years on 28 sites in southwestern Oregon. Seedbed...
Simulation study on combination of GRACE monthly gravity field solutions
NASA Astrophysics Data System (ADS)
Jean, Yoomin; Meyer, Ulrich; Jäggi, Adrian
2016-04-01
The GRACE monthly gravity fields from different processing centers are combined in the frame of the project EGSIEM. This combination is done on solution level first to define weights which will be used for a combination on normal equation level. The applied weights are based on the deviation of the individual gravity fields from the arithmetic mean of all involved gravity fields. This kind of weighting scheme relies on the assumption that the true gravity field is close to the arithmetic mean of the involved individual gravity fields. However, the arithmetic mean can be affected by systematic errors in individual gravity fields, which consequently results in inappropriate weights. For the future operational scientific combination service of GRACE monthly gravity fields, it is necessary to examine the validity of the weighting scheme also in possible extreme cases. To investigate this, we make a simulation study on the combination of gravity fields. Firstly, we show how a deviated gravity field can affect the combined solution in terms of signal and noise in the spatial domain. We also show the impact of systematic errors in individual gravity fields on the resulting combined solution. Then, we investigate whether the weighting scheme still works in the presence of outliers. The result of this simulation study will be useful to understand and validate the weighting scheme applied to the combination of the monthly gravity fields.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Korthals-Altes, C.P.; de Rafael, E.; Stora, R.
1975-07-01
This Colloquium was devoted to recent developments in the study of Lagrangian models of quantum field theory: renormalized pertubation theories; supergauge fields; asymptotic freedom and infrared slavery in gauge field models involving quarks; gauge fields on lattices; and theory of critical exponents. Papers were abstracted separately for the database.
ERIC Educational Resources Information Center
Vera, Elizabeth M.; Heineke, Amy; Carr, Andrea L.; Camacho, Daniel; Israel, Marla Susman; Goldberger, Nancy; Clawson, Angela; Hill, Martin
2017-01-01
This study sought to expand the field's understanding of the educational involvement of Latino parents whose children were English Learners and attended Catholic schools. Specifically, we attempted to identify factors that facilitate as well as prohibit involvement in two home-based types of educational involvement and two specific school-based…
A loop-gap resonator for chirality-sensitive nuclear magneto-electric resonance (NMER)
NASA Astrophysics Data System (ADS)
Garbacz, Piotr; Fischer, Peer; Krämer, Steffen
2016-09-01
Direct detection of molecular chirality is practically impossible by methods of standard nuclear magnetic resonance (NMR) that is based on interactions involving magnetic-dipole and magnetic-field operators. However, theoretical studies provide a possible direct probe of chirality by exploiting an enantiomer selective additional coupling involving magnetic-dipole, magnetic-field, and electric field operators. This offers a way for direct experimental detection of chirality by nuclear magneto-electric resonance (NMER). This method uses both resonant magnetic and electric radiofrequency (RF) fields. The weakness of the chiral interaction though requires a large electric RF field and a small transverse RF magnetic field over the sample volume, which is a non-trivial constraint. In this study, we present a detailed study of the NMER concept and a possible experimental realization based on a loop-gap resonator. For this original device, the basic principle and numerical studies as well as fabrication and measurements of the frequency dependence of the scattering parameter are reported. By simulating the NMER spin dynamics for our device and taking the 19F NMER signal of enantiomer-pure 1,1,1-trifluoropropan-2-ol, we predict a chirality induced NMER signal that accounts for 1%-5% of the standard achiral NMR signal.
This document describes field procedures that were used during the Environmental Monitoring and Assessment Program (EMAP) Western Pilot Study, conducted from 1999 through 2004. Objectives for EMAP involve developing appropriate scientific and technical tools for evaluating ecolo...
Medical review licensing outcomes in drivers with visual field loss in Victoria, Australia
Muir, Carlyn; Charlton, Judith L; Odell, Morris; Keeffe, Jill; Wood, Joanne; Bohensky, Megan; Fildes, Brian; Oxley, Jennifer; Bentley, Sharon; Rizzo, Matthew
2017-01-01
Background Good vision is essential for safe driving and studies have associated visual impairment with an increased crash risk. Currently, there is little information about the medical review of drivers with visual field loss. This study examines the prevalence of visual field loss among drivers referred for medical review in one Australian jurisdiction and investigates factors associated with licence outcome in this group. Methods A random sample of 10,000 (31.25 per cent) medical review cases was extracted for analysis from the Victorian licensing authority. Files were screened for the presence of six visual field-related medical conditions. Data were captured on a range of variables, including referral source, age, gender, health status, crash history and licence outcome. Prevalence analyses were univariate and descriptive. Logistic regression was used to assess factors associated with licence outcomes in the visual field loss group. Results Approximately 1.9 per cent of the 10,000 medical review cases screened had a visual field loss condition identified (n=194). Among the visual field loss group, 57.2 per cent were permitted to continue driving (conditional/unconditional licence). Primary referral sources were the police, self-referrals and general medical practitioners. Key factors associated with licence test outcomes were visual field condition, age group, crash involvement and referral to the Driver Licensing Authority’s Medical Advisors. Those who were younger had a crash involvement triggering referral and those who were referred to the Medical Advisors were more likely to have a positive licensing outcome. Conclusion The evidence base for making licensing decisions is complicated by the variable causes, patterns, progressions and measuring technologies for visual field loss. This study highlighted that the involvement of an expert medical advisory service in Victoria resulted in an increased likelihood that drivers with visual field loss will be allowed to continue driving. Further research is warranted to explore issues relating to severity of field loss and the capacity for compensation. PMID:27530283
Kim, Ji Eun; Nam, Jung Hoon; Cho, Joon Young; Kim, Kil Soo; Hwang, Dae Youn
2017-06-01
Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agriculture-fishery, and art-kinesiology fields by analyzing big data. Numbers of ICR mouse-used papers gradually increased from 1961 to 2014, but small decreases were observed in 2015 and 2016. The largest number of ICR-used papers were published in the medicine-pharmacy field, followed by natural science and art-kinesiology fields. There were no ICR mouse-used papers in other fields. Furthermore, ICR mice have been widely employed in cell biology studies within the natural science field as well as in biochemistry and pathology in the medicine-pharmacy field. Few ICR mouse-used papers were published in exercise biochemistry and exercise nutrition in the art-kinesiology field. Regardless in most fields, the total numbers of published papers involving ICR mice were higher in 2014 than in other years, although the numbers in some fields including dentistry, veterinary science, and dermatology were high in 2016. Taken together, the present study shows that various ICR stocks, including Korl:ICR mice, are widely employed as experimental animals in various biomedical research fields.
Kim, Ji Eun; Nam, Jung Hoon; Cho, Joon Young; Kim, Kil Soo
2017-01-01
Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agriculture-fishery, and art-kinesiology fields by analyzing big data. Numbers of ICR mouse-used papers gradually increased from 1961 to 2014, but small decreases were observed in 2015 and 2016. The largest number of ICR-used papers were published in the medicine-pharmacy field, followed by natural science and art-kinesiology fields. There were no ICR mouse-used papers in other fields. Furthermore, ICR mice have been widely employed in cell biology studies within the natural science field as well as in biochemistry and pathology in the medicine-pharmacy field. Few ICR mouse-used papers were published in exercise biochemistry and exercise nutrition in the art-kinesiology field. Regardless in most fields, the total numbers of published papers involving ICR mice were higher in 2014 than in other years, although the numbers in some fields including dentistry, veterinary science, and dermatology were high in 2016. Taken together, the present study shows that various ICR stocks, including Korl:ICR mice, are widely employed as experimental animals in various biomedical research fields. PMID:28747984
Simple, Low-Cost Data Collection Methods for Agricultural Field Studies.
ERIC Educational Resources Information Center
Koenig, Richard T.; Winger, Marlon; Kitchen, Boyd
2000-01-01
Summarizes relatively simple and inexpensive methods for collecting data from agricultural field studies. Describes methods involving on-farm testing, crop yield measurement, quality evaluations, weed control effectiveness, plant nutrient status, and other measures. Contains 29 references illustrating how these methods were used to conduct…
The US EPA has completed field data collections from a series of longitudinal particulate matter (PM) exposure panel field studies. These studies were conducted in Baltimore, Maryland (1998), Fresno, California (1999), and Research Triangle Park (RTP), North Carolina (2000-2001) ...
ERIC Educational Resources Information Center
Henley, Nancy M.
1985-01-01
Considers recent efforts within the field of psychology to understand issues involving gender. Demonstrates patterns of development within feminist psychology and its relation to mainstream psychology. Examines status of the field, two case studies, and new research. (Author/SA)
ERIC Educational Resources Information Center
An, Jihoun
2011-01-01
Parental involvement has been studied in the field of education since the 1970s. Scholars assert that parental involvement affects students' achievement and performance (Christenson, Rounds, & Gorney, 1992; Epstein, Sanders, Simons, Salinas, Janson, & Van Voorhis, 2002; Fan & Chen, 2001; Herman & Yeh, 1983; von Voorhis, 2003).…
Collier, Aileen; Wyer, Mary
2016-06-01
Patient safety research has to date offered few opportunities for patients and families to be actively involved in the research process. This article describes our collaboration with patients and families in two separate studies, involving end-of-life care and infection control in acute care. We used the collaborative methodology of video-reflexive ethnography, which has been primarily used with clinicians, to involve patients and families as active participants and collaborators in our research. The purpose of this article is to share our experiences and findings that iterative researcher reflexivity in the field was critical to the progress and success of each study. We present and analyze the complexities of reflexivity-in-the-field through a framework of multilayered reflexivity. We share our lessons here for other researchers seeking to actively involve patients and families in patient safety research using collaborative visual methods. © The Author(s) 2015.
Sensor Technology and Performance Characteristics
The US EPA is currently involved in detailed laboratory and/or field studies involving a wide variety of low cost air quality sensors currently being made available to potential citizen scientists. These devices include sensors associated with the monitoring of nitrogen dioxide (...
Strong field QED in lepton colliders and electron/laser interactions
NASA Astrophysics Data System (ADS)
Hartin, Anthony
2018-05-01
The studies of strong field particle physics processes in electron/laser interactions and lepton collider interaction points (IPs) are reviewed. These processes are defined by the high intensity of the electromagnetic fields involved and the need to take them into account as fully as possible. Thus, the main theoretical framework considered is the Furry interaction picture within intense field quantum field theory. In this framework, the influence of a background electromagnetic field in the Lagrangian is calculated nonperturbatively, involving exact solutions for quantized charged particles in the background field. These “dressed” particles go on to interact perturbatively with other particles, enabling the background field to play both macroscopic and microscopic roles. Macroscopically, the background field starts to polarize the vacuum, in effect rendering it a dispersive medium. Particles encountering this dispersive vacuum obtain a lifetime, either radiating or decaying into pair particles at a rate dependent on the intensity of the background field. In fact, the intensity of the background field enters into the coupling constant of the strong field quantum electrodynamic Lagrangian, influencing all particle processes. A number of new phenomena occur. Particles gain an intensity-dependent rest mass shift that accounts for their presence in the dispersive vacuum. Multi-photon events involving more than one external field photon occur at each vertex. Higher order processes which exchange a virtual strong field particle resonate via the lifetimes of the unstable strong field states. Two main arenas of strong field physics are reviewed; those occurring in relativistic electron interactions with intense laser beams, and those occurring in the beam-beam physics at the interaction point of colliders. This review outlines the theory, describes its significant novel phenomenology and details the experimental schema required to detect strong field effects and the simulation programs required to model them.
Communication Processes in the Field Research Interview Setting: A Case Study.
ERIC Educational Resources Information Center
Mason, Susan A.
For those involved in research of any type, the gathering of complete, relevant, and untainted information is the ultimate goal. The collection of valuable information is particularly challenging in the social sciences, which often call for qualitative field research. The effective field research interviewer must not only be knowledgeable of the…
Critical examination of quantum oscillations in SmB6
NASA Astrophysics Data System (ADS)
Riseborough, Peter S.; Fisk, Z.
2017-11-01
We critically review the results of magnetic torque measurements on SmB6 that show quantum oscillations. Similar studies have been given two different interpretations. One interpretation is based on the existence of metallic surface states, while the second interpretation is in terms of a three-dimensional Fermi surface involving neutral fermionic excitations. We suggest that the low-field oscillations that are seen by both groups for B fields as small as 6 T might be due to metallic surface states. The high-field three-dimensional oscillations are only seen by one group for fields B >18 T. The phenomenon of magnetic breakthrough occurs at high fields and involves the formation of Landau orbits that produces a directional-dependent suppression of Bragg scattering. We argue that the measurements performed under higher-field conditions are fully consistent with expectations based on a three-dimensional semiconducting state with magnetic breakthrough.
Huisingh, Carrie; Levitan, Emily B.; Irvin, Marguerite R.; MacLennan, Paul; Wadley, Virginia; Owsley, Cynthia
2017-01-01
Purpose An innovative methodology using naturalistic driving data was used to examine the association between visual sensory and visual-cognitive function and rates of future crash or near-crash involvement among older drivers. Methods The Strategic Highway Research Program (SHRP2) Naturalistic Driving Study was used for this prospective analysis. The sample consisted of N = 659 drivers aged ≥70 years and study participation lasted 1 or 2 years for most participants. Distance and near visual acuity, contrast sensitivity, peripheral vision, visual processing speed, and visuospatial skills were assessed at baseline. Crash and near-crash involvement were based on video recordings and vehicle sensors. Poisson regression models were used to generate crude and adjusted rate ratios (RRs) and 95% confidence intervals, while accounting for person-miles of travel. Results After adjustment, severe impairment of the useful field of view (RR = 1.33) was associated with an increased rate of near-crash involvement. Crash, severe crash, and at-fault crash involvement were associated with impaired contrast sensitivity in the worse eye (RRs = 1.38, 1.54, and 1.44, respectively) and far peripheral field loss in both eyes (RRs = 1.74, 2.32, and 1.73, respectively). Conclusions Naturalistic driving data suggest that contrast sensitivity in the worse eye and far peripheral field loss in both eyes elevate the rates of crash involvement, and impaired visual processing speed elevates rates of near-crash involvement among older drivers. Naturalistic driving data may ultimately be critical for understanding the relationship between vision and driving safety. PMID:28605807
Images of Imaging: Notes on Doing Longitudinal Field Work.
ERIC Educational Resources Information Center
Barley, Stephen R.
1990-01-01
Discusses the processes involved in a field study of technological change in radiology and how researchers can design a qualitative study and then collect data in a systematic and explicit manner. Illustrates the social and human problems of gaining entry into a research site, constructing a research role, and managing relationships. (63…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shikama, Naoto; Oguchi, Masahiko; Isobe, Koichi
2006-09-01
Purpose: We conducted a multicenter prospective study to evaluate the efficacy and safety of reduced-dose three-course CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) followed by involved-field radiotherapy for elderly patients with localized aggressive non-Hodgkin's lymphoma. The primary endpoint was compliance with the combined modality. Methods and Materials: This study included untreated patients, {>=}70 years old, with diffuse aggressive lymphoma, Stage IA or contiguous nonbulky Stage IIA. 80%-CHOP (cyclophosphamide 600 mg/m{sup 2}, doxorubicin 40 mg/m{sup 2}, vincristine 1.1 mg/m{sup 2}, and prednisolone at 80 mg/day for 5 days) was repeated every 3 weeks. After three cycles of chemotherapy, involved-field radiotherapy was performedmore » with a radiation dose of 30-50 Gy in 15-28 fractions. Results: Twenty-four patients with a median age of 75 years (range, 70-84 years) were enrolled. The compliance rate of the protocol study was 87.5% (95% confidence interval [CI], 67.6-97.3). Three patients received only two cycles of chemotherapy because of toxicity or second neoplasm. There were no deaths caused by severe toxicity. The 3-year progression-free and overall survival rates were 83.1% (95% CI, 75.4-90.8) and 82.9% (95% CI, 75.1-90.6), respectively. Conclusion: Three-course 80%-CHOP followed by involved-field radiotherapy may be safe for administration to elderly patients over 70 years old. The next step is to evaluate three-course 80%-CHOP and rituximab followed by radiotherapy in elderly patients with localized disease.« less
Improved decision making in construction using virtual site visits.
DOT National Transportation Integrated Search
2003-01-01
This study explored the dynamics of information exchange involving field issues relating to construction and the assistance that a virtual site visit can provide to the field decision-making process. Such a process can be used for inspection and surv...
The Floating Lab Research Project: An Approach to Evaluating Field Programs.
ERIC Educational Resources Information Center
Brody, Michael J.
This report explains an evaluative study of the conceptual and affective development of students associated with the Floating Lab Program, an experiential field project sponsored by the University of New Hampshire and the Maine Sea Grant Program. The field program involved an opportunity for students to have hands-on experiences aboard a 65-foot…
ERIC Educational Resources Information Center
McCulloch, Gary
2014-01-01
"Educational administration and the social sciences", the landmark text coedited by Baron and Taylor in 1969, represented the study of educational administration as an applied interdisciplinary field. George Baron's own academic career reveals the struggles involved in the construction of this new field and the resistance and opposition…
Nonclassical Properties of Q-Deformed Superposition Light Field State
NASA Technical Reports Server (NTRS)
Ren, Min; Shenggui, Wang; Ma, Aiqun; Jiang, Zhuohong
1996-01-01
In this paper, the squeezing effect, the bunching effect and the anti-bunching effect of the superposition light field state which involving q-deformation vacuum state and q-Glauber coherent state are studied, the controllable q-parameter of the squeezing effect, the bunching effect and the anti-bunching effect of q-deformed superposition light field state are obtained.
NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR CLEANING: FIELD FORMS (UA-D-38.0)
The purpose of this SOP is to define the steps involved in cleaning the electronic data generated from data entry of the field forms. It applies to electronic data corresponding to the field forms that were scanned and verified by data staff during the Arizona NHEXAS project and...
The purpose of this SOP is to define the steps involved in cleaning the electronic data generated from data entry of the field forms. It applies to electronic data corresponding to the field forms that were scanned and verified by data staff during the Arizona NHEXAS project and...
Promoting Field Trip Confidence: Teachers Providing Insights for Pre-Service Education
ERIC Educational Resources Information Center
Ateskan, Armagan; Lane, Jennie F.
2016-01-01
Pre-service teachers need experiences in practical matters as a part of field trip preparations programmes. For 14 years, a private, non-profit university in Turkey has involved pre-service teachers in field trip planning, implementation and evaluation. A programme assessment was conducted through a case study to examine the long-term effects of…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Huggins, A.W.
A field research effort was conducted in the vicinity of the Tushar Mountains of southern Utah as part of the Federal-State Program in Atmospheric Modification Research involving the National Oceanic and Atmospheric Administration and the State of Utah. The field study took place in February and March 1989 and emphasized the studies of supercooled liquid water evolution in winter storms and attempts to measure the effects of ground-based silver iodide cloud seeding. Results of the field effort are presented.
Chen, Ming; Bao, Yong; Ma, Hong-Lian; Wang, Jin; Wang, Yan; Peng, Fang; Zhou, Qi-Chao; Xie, Cong-Hua
2013-01-01
This prospective randomized study is to evaluate the locoregional failure and its impact on survival by comparing involved field radiotherapy (IFRT) with elective nodal irradiation (ENI) in combination with concurrent chemotherapy for locally advanced non-small cell lung cancer. It appears that higher dose could be delivered in IFRT arm than that in ENI arm, and IFRT did not increase the risk of initially uninvolved or isolated nodal failures. Both a tendency of improved locoregional progression-free survival and a significant increased overall survival rate are in favor of IFRT arm in this study. PMID:23762840
Families Writing Together: The Experience of English Language Learner Families in a Writing Workshop
ERIC Educational Resources Information Center
Korab, Elizabeth
2010-01-01
The purpose of this qualitative study was to gain a greater understanding of English language learner (ELL) family involvement in school environments through the lens of family literacy. This study was informed by literature from two fields: early childhood writing and ELL family involvement. While some schools have focused on at-home reading…
A series of modeling simulations were performed to develop an understanding of the underlying factors and principles involved in developing field sampling designs for measuring bioaccumulation factors (BAFs) and biota-sediment accumulation factors (BSAFs. These simulations reveal...
ERIC Educational Resources Information Center
Heng, Tang T.
2014-01-01
While the parental involvement field has progressed from asking what the impact of parental involvement is to how we can better involve parents, research has lagged in finding out how sociocultural and class differentials between homes and schools affect immigrant families' interactions with schools. This case study uses ethnographic tools to…
A comparison of alcohol involvement in pedestrians and pedestrian casualties
DOT National Transportation Integrated Search
1979-10-01
A field accident research study was conducted in the City of New Orleans in : 1975-76 in order to (1) determine the percentage and relative risk of alcohol involvement : in adult pedestrian fatal and injury accidents; (2) identify in the alcohol invo...
An evaluation of corn earworm damage and thresholds in soybean
NASA Astrophysics Data System (ADS)
Adams, Brian Patrick
Interactions between corn earworm, Helicoverpa zea (Boddie), and soybean, Glycine max L. (Merrill), were investigated in the Mid-South to evaluate thresholds and damage levels. Field studies were conducted in both indeterminate and determinate modern cultivars to evaluate damage, critical injury levels, and soybean response to simulated corn earworm injury. Field studies were also conducted to evaluate the response of indeterminate cultivars to infestations of corn earworm. Field studies were also conducted to investigate the relationship between pyrethroid insecticide application and corn earworm oviposition in soybean. Results of field studies involving simulated corn earworm damage indicated the need for a dynamic threshold that becomes more conservative as soybean phenology progressed through the reproductive growth stages. This suggested that soybean was more tolerant to fruit loss during the earlier reproductive stages and was able to compensate for fruit loss better during this time than at later growth stages. Results of field studies involving infestations of corn earworm indicated that current thresholds are likely too liberal. This resulted in economic injury level tables being constructed based upon a range of crop values and control costs, however, a general action threshold was also recommended for indeterminate soybean in the Mid-South. Field study results investigating the relationship of pyrethroid application and corn earworm oviposition indicated that even in the presence of an insecticide, corn earworm prefers to oviposit in the upper portion of the canopy, as well as on the leaves as opposed to all other plant parts, consistent with all previous literature.
Spinosad resistance in female Musca domestica L. from a field-derived population.
Markussen, Mette D K; Kristensen, Michael
2012-01-01
Bait-formulated spinosad is currently being introduced for housefly (Musca domestica L.) control around the world. Spinosad resistance was evaluated in a multiresistant field population and strains derived from this by selection with insecticides. Constitutive and spinosad-induced expression levels of three cytochrome P450 genes, CYP6A1, CYP6D1 and CYP6D3, previously reported to be involved in insecticide resistance, were examined. In 2004 a baseline for spinosad toxicity of Danish houseflies where all field populations were considered to be susceptible was established. In the present study, females of a multiresistant field population 791a were, however, 27-fold spinosad resistant at LC(50), whereas 791a male houseflies were susceptible. Strain 791a was selected with spinosad, thiamethoxam, fipronil and imidacloprid, resulting in four strains with individual characteristics. Selection of 791a with spinosad did not alter spinosad resistance in either males or females, but counterselected against resistance to the insecticides thiamethoxam and imidacloprid targeting nicotinic acetylcholine receptors. A synergist study with piperonyl butoxide, as well as gene expression studies of CYP6A1, CYP6D1 and CYP6D3, indicated a partial involvement of cytochrome P450 genes in spinosad resistance. This study reports female-linked spinosad resistance in Danish houseflies. Negative cross-resistance was observed between spinosad and neonicotinoids in one multiresistant housefly strain. Spinosad resistance involved alterations of cytochrome P450 gene expression. Copyright © 2011 Society of Chemical Industry.
ERIC Educational Resources Information Center
Aarnio, Pauliina; Kulmala, Teija
2016-01-01
Self-interview methods such as audio computer-assisted self-interviewing (ACASI) are used to improve the accuracy of interview data on sensitive topics in large trials. Small field studies on sensitive topics would benefit from methodological alternatives. In a study on male involvement in antenatal HIV testing in a largely illiterate population…
MEASURING THE MAGNETIC FIELD OF CORONAL MASS EJECTIONS NEAR THE SUN USING PULSARS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Howard, T. A.; Stovall, K.; Dowell, J.
The utility of Faraday rotation to measure the magnetic field of the solar corona and large-scale transients within is a small, yet growing field in solar physics. This is largely because it has been recognized as a potentially valuable frontier in space weather studies, because the ability to measure the intrinsic magnetic field within coronal mass ejections (CMEs) when they are close to the Sun is of great interest for understanding a key element of space weather. Such measurements have been attempted over the last few decades using radio signals from artificial sources (i.e., spacecraft on the far side ofmore » the Sun), but studies involving natural radio sources are scarce in the literature. We report on a preliminary study involving an attempt to detect the Faraday rotation of a CME that passed in front of a pulsar (PSR B0950+08) in 2015 August. We combine radio measurements with those from a broadband visible light coronagraph, to estimate the upper limit of the magnetic field of the CME when it was in the corona. We find agreement between different approaches for obtaining its density, and values that are consistent with those predicted from prior studies of CME density close to the Sun.« less
NASA Astrophysics Data System (ADS)
Mccann, A. R.; Cardace, D.; Carnevale, D.
2011-12-01
The role of technology is an increasingly important resource in preparing students for the future. The Internet is a widely accessible tool. Technology has also made us more connected, allowing constant communication and instantaneous data sharing. Public utilities such as those found on the web, including blogs, are a means to convey scientific research in rapid, useful ways. This tool is ideal for newly emerging fields, allowing up-to-date collaboration and referencing of ongoing studies, as well as bringing students virtually into the field or laboratory through videos, pictures, and records of project work. Astrobiology is a high interest topic, integrating geology, chemistry, biology, and physics. Terrestrial Mars analog environments are compelling in that they shed light on unusual opportunities for diverse life in settings beyond Earth. For this study, the analog site locality is at the University of California-Davis McLaughlin Natural Reserve in the Coast Range Ophiolite, a portion of actively serpentinizing, uplifted oceanic material in northern California (see companion poster, McCann et al., Mineralogy of Surface Serpentinite Outcrops in the Coast Range Ophiolite: Implications for the Deep Biosphere and Astrobiology). Our research objective is to monitor the activity taking place within the subsurface biosphere through an interdisciplinary approach involving biogeochemists, microbiologists, organic geochemists, and geologists. The study of serpentinization with astrobiological ground-truthing is a relatively new and promising field. Scientific field procedures are constantly being modified as they are applied. In order to better collaborate study efforts, a daily field journal is being written, recording ideas, discussions, procedures, problems, solutions, and results. It serves as an informal report, including pictures and video clips of the field activity. The journal is maintained as an online blog for ease of use and accessibility, as well as public comment. Its secondary purpose is to serve as a resource oriented toward high school science classrooms interested in cutting edge scientific endeavors. Included are video interviews of each participating scientist, covering topics such as professional background, past studies, their parts in the ongoing project and what they hope to gain through this research. By piecing together the various scientific approaches with the procedural field work, I am simplifying the massive amount of details involved between proposing a project and having a presentable result. As a high school student, the enormity of research possibilities can be in awe-inspiring contrast with the precision of the end result. This blog is interlocking the important components of our field campaign so that the audience will understand better the tasks involved in the field of scientific research. It not only will bring clarity and realism to the scientific process, but will serve to convey the passion and life involved in the research by the people that love what they do.
Chemical enhanced oil recovery (EOR) activities in Indonesia: How it's future
NASA Astrophysics Data System (ADS)
Abdurrahman, Muslim
2017-05-01
Enhanced oil recovery (EOR) is a proven method for increasing oil production in many oil fields in the world. Huge oil remaining in the reservoir after primary and secondary recovery stage are the main reason for developing EOR methods. Approximately of 49.50 billion barrels oil as a candidate for EOR activities in Indonesia. This present study focuses on the chemical EOR activities involved surfactant and polymer. This research based on pertinent information from various resources such as journal papers, conference papers, and report from the government. Based on this information, this paper explain in detail the progress of each project and it shows the potential oil field employ chemical EOR in the near future. Generally, the EOR activities can be categorized into two phases such as preliminary study phase and field implementation phase. In the preliminary study, the activities simply involve experimental and/or simulation works. Following the preliminary is the field implementation phase which can be categorized into three phases such as field trial, pilot project, and full-scale. In fact, several activities have been conducted by Lemigas (government oil and gas research center), Institut Teknologi Bandung, Institut Pertanian Bogor. These activities focused on laboratory and simulation work. Those institutions have been developing the chemical formula collaborating with oil companies for applying the EOR method in their oil fields. Currently, status of chemical EOR activities include 5 oil fields under pilot project and 12 oil fields under field trial. There are 7 oil fields applying surfactant, 4 oil fields by alkaline-surfactant-polymer (ASP), 2 oil fields by polymer, 1 oil field by surfactant polymer (SP), and 1 oil field by caustic. According to this information, we will have insight knowledge about the EOR current activities, the main issues, future activities on chemical EOR in Indonesia. Moreover, this study can became the preliminary information for researchers who interested conducting further research and development on the chemical EOR activities in the near future.
Evidence from the Scene: paramedic perspectives on involvement in out-of-hospital research
Watson, Duika L. Burges; Sanoff, Randy; Mackintosh, Joan E; Saver, Jeffrey L.; Ford, Gary A.; Price, Christopher; Starkman, Sid; Eckstein, Marc; Conwit, Robin; Grace, Anna; Murtagh, Madeleine J
2012-01-01
Study Objective In the context of calls to develop better systems for out-of-hospital clinical research we sought to understand: 1) paramedics’ perceptions of involvement in research, and 2) the barriers and facilitators to their involvement in research. Methods Qualitative study. Semi-structured focus groups with 58 UK paramedics and interviews with 30 US firefighter-paramedics. The research focused on out-of-hospital research (trials of pre-hospital treatment for stroke) whereby paramedics identify potential study subjects or obtain consent and administer study treatment in the field. Data were analysed using a thematic and discourse approach. Results Three key themes emerged as significant facilitators and barriers to paramedic involvement in research: ‘patient benefit’, ‘professional identity and responsibility’ and ‘time’. Paramedics showed willingness and capacity to engage in research but also some reticence due to the perceived sacrifice of autonomy and challenge to their identity. Paramedics work in a time sensitive environment and were concerned that research should not increase time taken in the field. Conclusions Awareness of these perspectives will help with development of pre-hospital research protocols and potentially facilitate greater participation. PMID:22387089
Maeda, Kiminori; Storey, Jonathan G; Liddell, Paul A; Gust, Devens; Hore, P J; Wedge, C J; Timmel, Christiane R
2015-02-07
We present a study of a carotenoid-porphyrin-fullerene triad previously shown to function as a chemical compass: the photogenerated carotenoid-fullerene radical pair recombines at a rate sensitive to the orientation of an applied magnetic field. To characterize the system we develop a time-resolved Low-Frequency Reaction Yield Detected Magnetic Resonance (tr-LF-RYDMR) technique; the effect of varying the relative orientation of applied static and 36 MHz oscillating magnetic fields is shown to be strongly dependent on the strength of the oscillating magnetic field. RYDMR is a diagnostic test for involvement of the radical pair mechanism in the magnetic field sensitivity of reaction rates or yields, and has previously been applied in animal behavioural experiments to verify the involvement of radical-pair-based intermediates in the magnetic compass sense of migratory birds. The spectroscopic selection rules governing RYDMR are well understood at microwave frequencies for which the so-called 'high-field approximation' is valid, but at lower frequencies different models are required. For example, the breakdown of the rotating frame approximation has recently been investigated, but less attention has so far been given to orientation effects. Here we gain physical insights into the interplay of the different magnetic interactions affecting low-frequency RYDMR experiments performed in the challenging regime in which static and oscillating applied magnetic fields as well as internal electron-nuclear hyperfine interactions are of comparable magnitude. Our observations aid the interpretation of existing RYDMR-based animal behavioural studies and will inform future applications of the technique to verify and characterize further the biological receptors involved in avian magnetoreception.
Spray combustion under oscillatory pressure conditions
NASA Technical Reports Server (NTRS)
Jacobs, H. R.; Santoro, R. J.
1991-01-01
The performance and stability of liquid rocket engines is often argued to be significantly impacted by atomization and droplet vaporization processes. In particular, combustion instability phenomena may result from the interactions between the oscillating pressure field present in the rocket combustor and the fuel and oxidizer injection process. Few studies have been conducted to examine the effects of oscillating pressure fields on spray formation and its evolution under rocket engine conditions. The pressure study is intended to address the need for such studies. In particular, two potentially important phenomena are addressed in the present effort. The first involves the enhancement of the atomization process for a liquid jet subjected to an oscillating pressure field of known frequency and amplitude. The objective of this part of the study is to examine the coupling between the pressure field and or the resulting periodically perturbed velocity field on the breakup of the liquid jet. In particular, transverse mode oscillations are of interest since such modes are considered of primary importance in combustion instability phenomena. The second aspect of the project involves the effects of an oscillating pressure on droplet coagulation and secondary atomization. The objective of this study is to examine the conditions under which phenomena following the atomization process are affected by perturbations to the pressure or velocity fields. Both coagulation and represent a coupling mechanism between the pressure field and the energy release process in rocket combustors. It is precisely this coupling which drives combustion instability phenomena. Consequently, the present effort is intended to provide the fundamental insights needed to evaluate these processes as important mechanisms in liquid rocket instability phenomena.
Field sampling and travel report
USDA-ARS?s Scientific Manuscript database
Dr. Sigua was involved with two field visits of watersheds with different livestock production systems (poultry, swine, and beef/dairy cattle); one in the sub-basins of Pinhal River Watershed (October 23, 2008) and at the micro-basins of the Rio Pine Forest (October 29, 2008) where studies of assess...
Persistence of undergraduate women in STEM fields
NASA Astrophysics Data System (ADS)
Pedone, Maggie Helene
The underrepresentation of women in science, technology, engineering, and mathematics (STEM) is a complex problem that continues to persist at the postsecondary level, particularly in computer science and engineering fields. This dissertation explored the pre-college and college level factors that influenced undergraduate women's persistence in STEM. This study also examined and compared the characteristics of undergraduate women who entered STEM fields and non-STEM fields in 2003-2004. The nationally representative Beginning Postsecondary Students Longitudinal Study (BPS:04/09) data set was used for analysis. BPS:04/09 study respondents were surveyed three times (NPSAS:04, BPS:04/06, BPS:04/09) over a six-year period, which enabled me to explore factors related to long-term persistence. Astin's Input-Environment-Output (I-E-O) model was used as the framework to examine student inputs and college environmental factors that predict female student persistence (output) in STEM. Chi-square tests revealed significant differences between undergraduate women who entered STEM and non-STEM fields in 2003-2004. Differences in student demographics, prior academic achievement, high school course-taking patterns, and student involvement in college such as participation in study groups and school clubs were found. Notably, inferential statistics showed that a significantly higher proportion of female minority students entered STEM fields than non-STEM fields. These findings challenge the myth that underrepresented female minorities are less inclined to enter STEM fields. Logistic regression analyses revealed thirteen significant predictors of persistence for undergraduate women in STEM. Findings showed that undergraduate women who were younger, more academically prepared, and academically and socially involved in college (e.g., lived on campus, interacted with faculty, participated in study groups, fine arts activities, and school sports) were more likely to persist in STEM fields. This longitudinal study showed that both pre-college and college level factors influenced undergraduate women's persistence in STEM. The research findings offer important implications for policy and practice initiatives in higher education that focus on the recruitment and retention of women in postsecondary STEM fields.
ERIC Educational Resources Information Center
Barry, Nancy H.
This paper reports on a study examining preservice teachers' level of comfort in working with students and colleagues of a different race, and exploring the effects of special training and field experience on their level of comfort with multicultural situations. The study involved 55 predominantly white preservice teachers enrolled in 2 different…
The U.S. Role in International Disability Activities: A History and a Look towards the Future.
ERIC Educational Resources Information Center
Groce, Nora
This study presents an introduction to U.S. involvement in the field of international rehabilitation and disability. Oral history interviews were conducted with 21 "distinguished elders" in the field, an oral history conference with 18 of the elders was held and documented, and written sources were reviewed. The study includes: (1) a…
Corn blight review: Sampling model and ground data measurements program
NASA Technical Reports Server (NTRS)
Allen, R. D.
1972-01-01
The sampling plan involved the selection of the study area, determination of the flightline and segment sample design within the study area, and determination of a field sample design. Initial interview survey data consisting of crop species acreage and land use were collected. On all corn fields, additional information such as seed type, row direction, population, planting date, ect. were also collected. From this information, sample corn fields were selected to be observed through the growing season on a biweekly basis by county extension personnel.
Chaotic structures of nonlinear magnetic fields. I - Theory. II - Numerical results
NASA Technical Reports Server (NTRS)
Lee, Nam C.; Parks, George K.
1992-01-01
A study of the evolutionary properties of nonlinear magnetic fields in flowing MHD plasmas is presented to illustrate that nonlinear magnetic fields may involve chaotic dynamics. It is shown how a suitable transformation of the coupled equations leads to Duffing's form, suggesting that the behavior of the general solution can also be chaotic. Numerical solutions of the nonlinear magnetic field equations that have been cast in the form of Duffing's equation are presented.
Zhu, Yefei; Wang, Chunlei; Chen, Xiaowu; Guan, Guijun
2016-07-01
We studied molecular events and potential mechanisms underlying the process of female-to-male sex transformation in the rice field eel (Monopterus albus), a protogynous hermaphrodite fish in which the gonad is initially a female ovary and transforms into male testes. We cloned and identified a novel gonadal soma derived factor (GSDF), which encodes a member of the transforming growth factor-beta superfamily. gsdf expression was measured in gonads of female, intersex and male with reverse transcription-PCR and gsdf's role in sex transformation was studied with qPCR, histological analysis and dual-color in situ hybridization assays and compared to other sex-related genes. gsdf was correlated to Sertoli cell differentiation, indicating involvement in testicular differentiation and sex transformation from female to male in this species. A unique expression pattern reveals a potential role of gsdf essential for the sex transformation of rice field eels.
NASA Astrophysics Data System (ADS)
Ju, Kyong-Sik; Ryo, Hyok-Su; Pak, Sung-Nam; Pak, Chang-Su; Ri, Sung-Guk; Ri, Dok-Hwan
2018-07-01
By using the generalized inverse-pole-figure model, the numbers of crystalline particles involved in different domain-switching near the triple tetragonal-rhombohedral-orthorhombic (T-R-O) points of three-phase polycrystalline ferroelectrics have been analytically calculated and domain-switching which can bring out phase transformations has been considered. Through polarization by an electric field, different numbers of crystalline particles can be involved in different phase transformations. According to the phase equilibrium conditions, the phase equilibrium compositions of the three phases coexisting near the T-R-O triple point have been evaluated from the results of the numbers of crystalline particles involved in different phase transformations.
Practices of Cooperating Teachers Contributing to a High Quality Field Experience
ERIC Educational Resources Information Center
Lafferty, Karen Elizabeth
2015-01-01
This mixed methods study framed in cognitive apprenticeship theory involved cooperating and preservice teachers from 10 university-based credentialing programs in California. It examined the connection between cooperating teacher practices and preservice teachers' perceptions of a high quality field experience. Survey responses from 146…
Involved-Field, Low-Dose Chemoradiotherapy for Early-Stage Anal Carcinoma
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hatfield, Paul; Cooper, Rachel; Sebag-Montefiore, David
2008-02-01
Purpose: To report the results of patients with early-stage anal cancer treated using a low-dose, reduced-volume, involved-field chemoradiotherapy protocol. Methods and Materials: Between June 2000 and June 2006, 21 patients were treated with external beam radiotherapy (30 Gy in 15 fractions within 3 weeks) and concurrent chemotherapy (bolus mitomycin-C 12 mg/m{sup 2} on Day 1 to a maximum of 20 mg followed by infusion 5-fluorouracil 1,000 mg/m{sup 2}/24 h on Days 1-4). Of the 21 patients, 18 underwent small-volume, involved-field radiotherapy and 3 were treated with anteroposterior-posteroanterior parallel-opposed pelvic fields. Of the 21 patients, 17 had had lesions that weremore » excised with close (<1 mm) or involved margins, 1 had had microinvasive disease on biopsy, and 3 had had macroscopic tumor <2 cm in diameter (T1). All were considered to have Stage N0 disease radiologically. Results: After a median follow-up of 42 months, only 1 patient (4.7%) had experienced local recurrence and has remained disease free after local excision. No distant recurrences or deaths occurred. Only 1 patient could not complete treatment (because of Grade 3 gastrointestinal toxicity). Grade 3-4 hematologic toxicity occurred in only 2 patients (9.5%). No significant late toxicity was identified. Conclusion: The results of our study have shown that for patients with anal carcinoma who have residual microscopic or very-small-volume disease, a policy of low-dose, reduced-volume, involved-field chemoradiotherapy produces excellent local control and disease-free survival, with low rates of acute and late toxicity.« less
Kesarwala, Aparna H.; Ko, Christine J.; Ning, Holly; Xanthopoulos, Eric; Haglund, Karl E.; O’Meara, William P.; Simone, Charles B.; Rengan, Ramesh
2015-01-01
Background Photon involved-field radiation therapy (IFRT), the standard for locally advanced non-small cell lung cancer (LA-NSCLC), results in favorable outcomes without increased isolated nodal failures, perhaps from scattered dose to elective nodal stations. Given the high conformality of intensity-modulated proton therapy (IMPT), proton IFRT could increase nodal failures. We investigated the feasibility of IMPT for elective nodal irradiation (ENI) in LA-NSCLC. Materials and Methods IMPT IFRT plans were generated to the same total dose of 66.6–72 Gy received by 20 LA-NSCLC patients treated with photon IFRT. IMPT ENI plans were generated to 46 CGE to elective nodal (EN) planning treatment volumes (PTV) plus 24 CGE to involved field (IF)-PTVs. Results Proton IFRT and ENI both improved D95 involved field (IF)-PTV coverage by 4% (p<0.01) compared to photon IFRT. All evaluated dosimetric parameters improved significantly with both proton plans. Lung V20 and mean lung dose decreased 18% (p<0.01) and 36% (p<0.01), respectively, with proton IFRT and 11% (p=0.03) and 26% (p<0.01) with ENI. Mean esophagus dose decreased 16% with IFRT and 12% with ENI; heart V25 decreased 63% with both (all p<0.01). Conclusions This study demonstrates the feasibility of IMPT for LA-NSCLC ENI. Potential decreased toxicity indicates IMPT could allow ENI while maintaining a favorable therapeutic ratio compared to photon IFRT. PMID:25604729
Teaching Geology in Situ: Modern Approaches and Perspectives
NASA Astrophysics Data System (ADS)
Rakhmenkulova, I. F.
2014-12-01
Geology and Geophysics Department of Novosibirsk State University (GGD NSU) is famous not only because of its specific location in Academgorodok (Novosibirsk, Russia) but because of its unique traditions: - conception of permanent geology education (starting from school to scientific research for postgraduate programs) - flexible curricula allowing students to be involved in research from the second year of study - field trips covering not only famous geologic objects in Siberia (Baikal, Siberian Traps, Altay, etc.), but places all over the world. GGD students traditionally participate in the following field trips: Altay (after the first year of study), Shira (Krasnoyarsk Krai) (after the second year of study). Further field trips are real research projects and cover various places in Siberia, Russia and other countries (China, Africa, USA, Mongolia, etc.). Shira field camp is of specific interest not only because of its various geology and interesting location (it is located in the resort area surrounded by beautiful landscapes, fresh and salt lakes of various salinity) but infrastructure. This year the Top 100 Project allows the department to upgrade the camp and therefore use it not only for field trips, but for other various purposes including international conferences, research projects, geo- and ecotourism. GGD NSU is ready to be involved into research, exchange educational programs and other projects (both domestically and internationally) based on the renewed Shira field camp.
Ranking predatory journals in dermatology: distinguishing the bad from the ugly.
Tosti, Antonella; Maddy, Austin J
2017-07-01
The scientific community depends on high-quality peer-reviewed research, which is being polluted with pseudoscience published in fake journals that have exploited the open-access model. This "predatory publishing" has made its way into the field of dermatology. In a recent study, we identified and listed these journals. The "predatory rate" was calculated for 76 journals in order to rank the journals based on specific criteria associated with unethical publishing. Of the 76 journals, 89.5% were classified as predatory journals and the remaining as journals involved in predatory practices. The field of dermatology is not immune to predatory publishers. This study validates Beall's list as well as other previous studies. Strategies to a solution include spreading awareness throughout academic institutions and dermatology departments as well as avoiding publishers that are involved in predatory practices. However, some journals may be able to make necessary adjustments and become legitimate contributors to the field. © 2017 The International Society of Dermatology.
Development of Scatterometer-Derived Surface Pressures
NASA Astrophysics Data System (ADS)
Hilburn, K. A.; Bourassa, M. A.; O'Brien, J. J.
2001-12-01
SeaWinds scatterometer-derived wind fields can be used to estimate surface pressure fields. The method to be used has been developed and tested with Seasat-A and NSCAT wind measurements. The method involves blending two dynamically consistent values of vorticity. Geostrophic relative vorticity is calculated from an initial guess surface pressure field (AVN analysis in this case). Relative vorticity is calculated from SeaWinds winds, adjusted to a geostrophic value, and then blended with the initial guess. An objective method applied minimizes the differences between the initial guess field and scatterometer field, subject to regularization. The long-term goal of this project is to derive research-quality pressure fields from the SeaWinds winds for the Southern Ocean from the Antarctic ice sheet to 30 deg S. The intermediate goal of this report involves generation of pressure fields over the northern hemisphere for testing purposes. Specifically, two issues need to be addressed. First, the most appropriate initial guess field will be determined: the pure AVN analysis or the previously assimilated pressure field. The independent comparison data to be used in answering this question will involve data near land, ship data, and ice data that were not included in the AVN analysis. Second, the smallest number of pressure observations required to anchor the assimilated field will be determined. This study will use Neumann (derivative) boundary conditions on the region of interest. Such boundary conditions only determine the solution to within a constant that must be determined by a number of anchoring points. The smallness of the number of anchoring points will demonstrate the viability of the general use of the scatterometer as a barometer over the oceans.
ERIC Educational Resources Information Center
Koca, Canan; Atencio, Matthew; Demirhan, Giyasettin
2009-01-01
This paper draws on Bourdieu's notions of habitus, social field, and capital to provide a more complex examination of the place and meaning of physical education in Turkish young people's lives. Two secondary schools comprised of students from quite distinctive social, cultural, and geographical locations were involved in the study. Collected data…
Multi-site field studies were conducted to evaluate the performance of sampling methods for measuring the coarse fraction of PM10 (PM10 2.5) in ambient air. The field studies involved the use of both time-integrated filter-based and direct continuous methods. Despite operationa...
de Melo, Roger Duarte; Acosta-Avalos, Daniel
2017-02-01
'Candidatus Magnetoglobus multicellularis' is the most studied multicellular magnetotactic prokaryote. It presents a light-dependent photokinesis: green light decreases the translation velocity whereas red light increases it, in comparison to blue and white light. The present article shows that radio-frequency electromagnetic fields cancel the light effect on photokinesis. The frequency to cancel the light effect corresponds to the Zeeman resonance frequency (DC magnetic field of 4 Oe and radio-frequency of 11.5 MHz), indicating the involvement of a radical pair mechanism. An analysis of the orientation angle relative to the magnetic field direction shows that radio-frequency electromagnetic fields disturb the swimming orientation when the microorganisms are illuminated with red light. The analysis also shows that at low magnetic fields (1.6 Oe) the swimming orientation angles are well scattered around the magnetic field direction, showing that magnetotaxis is not efficiently in the swimming orientation to the geomagnetic field. The results do not support cryptochrome as being the responsible chromophore for the radical pair mechanism and perhaps two different chromophores are necessary to explain the radio-frequency effects.
2014-01-01
We experimentally studied the magneto-photocurrents generated by direct interband transition in InAs/GaSb type II superlattice. By varying the magnetic field direction, we observed that an in-plane magnetic field induces a photocurrent linearly proportional to the magnetic field; however, a magnetic field tilted to the sample plane induces a photocurrent presenting quadratic magnetic field dependence. The magneto-photocurrents in both conditions are insensitive to the polarization state of the incident light. Theoretical models involving excitation, relaxation and Hall effect are utilized to explain the experimental results. PMID:24936166
Factors Influencing Learning through Play in ICT Settings
ERIC Educational Resources Information Center
Kennewell, Steve; Morgan, Alex
2006-01-01
Using a mixed method approach of questionnaires, observations and field notes, the authors have studied a number of settings during the past two years which have focussed on the development of ICT capability through play. Some of these have involved children identified as disaffected or disadvantaged, whilst others have involved initial teacher…
A role for physicians in ethnopharmacology and drug discovery.
Raza, Mohsin
2006-04-06
Ethnopharmacology investigations classically involved traditional healers, botanists, anthropologists, chemists and pharmacologists. The role of some groups of researchers but not of physician has been highlighted and well defined in ethnopharmacological investigations. Historical data shows that discovery of several important modern drugs of herbal origin owe to the medical knowledge and clinical expertise of physicians. Current trends indicate negligible role of physicians in ethnopharmacological studies. Rising cost of modern drug development is attributed to the lack of classical ethnopharmacological approach. Physicians can play multiple roles in the ethnopharmacological studies to facilitate drug discovery as well as to rescue authentic traditional knowledge of use of medicinal plants. These include: (1) Ethnopharmacological field work which involves interviewing healers, interpreting traditional terminologies into their modern counterparts, examining patients consuming herbal remedies and identifying the disease for which an herbal remedy is used. (2) Interpretation of signs and symptoms mentioned in ancient texts and suggesting proper use of old traditional remedies in the light of modern medicine. (3) Clinical studies on herbs and their interaction with modern medicines. (4) Advising pharmacologists to carryout laboratory studies on herbs observed during field studies. (5) Work in collaboration with local healers to strengthen traditional system of medicine in a community. In conclusion, physician's involvement in ethnopharmacological studies will lead to more reliable information on traditional use of medicinal plants both from field and ancient texts, more focused and cheaper natural product based drug discovery, as well as bridge the gap between traditional and modern medicine.
Factors motivating Cambodian American students to go to college and to study STEM fields
NASA Astrophysics Data System (ADS)
Sann, Visna
Cambodian Americans graduate from college at a lower rate than most Asian American groups. This qualitative study involved interviewing five current Cambodian American college students. This study examined how participants' high school experiences contributed to their decisions to go to college and to study STEM fields, how parental influences guided participants to college, and how college experiences influenced their decisions to stay and succeed in STEM fields. Findings from this study suggest: having supportive teachers in high school may have been important in motivating participants to go to college and to study STEM Fields, Cambodian parents tell stories of their lives in Cambodia to motivate their children to go to college, and Cambodian club on campus was a socially and academically supportive place.
Validating an Environmental Education Field Day Observation Tool
ERIC Educational Resources Information Center
Carlson, Stephan P.; Heimlich, Joe E.; Storksdieck, Martin
2011-01-01
Environmental Field Days (EFD) are held throughout the country and provide a unique opportunity to involve students in real world science. A study to assess the validity of an observation tool for EFD programs was conducted at the Metro Water Festival with fifth grade students. Items from the observation tool were mapped to students' evaluation…
Understanding Chemical Change in Primary Education: The Effect of Two Cognitive Variables
ERIC Educational Resources Information Center
Stamovlasis, Dimitrios; Papageorgiou, George
2012-01-01
In this study, pupils' understanding of chemical change was investigated in relation to two cognitive variables: logical thinking and field-dependence/field-independence. The participants (N = 99) were sixth-grade elementary school pupils (aged 11/12), which were involved in two different tasks related to combustion. The pupils were tested for…
In Old Pompeii. [Lesson Plan].
ERIC Educational Resources Information Center
2001
In this Web-based interdisciplinary lesson (involving social studies, geography, history, and language arts) students take a virtual field trip to the ruins of Pompeii to learn about everyday life in Roman times, then create a travelogue to attract visitors to the site and write an account of their field trip modeled on a description of Pompeii…
Improving Classroom Acoustics (ICA): A Three-Year FM Sound Field Classroom Amplification Study.
ERIC Educational Resources Information Center
Rosenberg, Gail Gegg; Blake-Rahter, Patricia; Heavner, Judy; Allen, Linda; Redmond, Beatrice Myers; Phillips, Janet; Stigers, Kathy
1999-01-01
The Improving Classroom Acoustics (ICA) special project was designed to determine if students' listening and learning behaviors improved as a result of an acoustical environment enhanced through the use of FM sound field classroom amplification. The 3-year project involved 2,054 students in 94 general education kindergarten, first-, and…
ERIC Educational Resources Information Center
Messaoudi, Belkacem; Granjon, Lionel; Mouly, Anne-Marie; Sevelinges, Yannick; Gervais, Remi
2004-01-01
The widely used Pavlovian fear-conditioning paradigms used for studying the neurobiology of learning and memory have mainly used auditory cues as conditioned stimuli (CS). The present work assessed the neural network involved in olfactory fear conditioning, using olfactory bulb stimulation-induced field potential signal (EFP) as a marker of…
ERIC Educational Resources Information Center
Bargerhuff, Mary Ellen; Cole, Donna J.; Teeters, Laura
2012-01-01
This paper examines the contradiction between articulated university policy on diversity/inclusion and actual practice with regard to field placements for teacher candidates with disabilities. Analysis of a unique case study involving a teacher candidate with traumatic brain injury illustrates the inequities of the traditional concern conference…
Holocene volcanism of the upper McKenzie River catchment, central Oregon Cascades, USA
Deligne, Natalia I.; Conrey, Richard M.; Cashman, Katharine V.; Champion, Duane E.; Amidon, William H.
2016-01-01
To assess the complexity of eruptive activity within mafic volcanic fields, we present a detailed geologic investigation of Holocene volcanism in the upper McKenzie River catchment in the central Oregon Cascades, United States. We focus on the Sand Mountain volcanic field, which covers 76 km2 and consists of 23 vents, associated tephra deposits, and lava fields. We find that the Sand Mountain volcanic field was active for a few decades around 3 ka and involved at least 13 eruptive units. Despite the small total volume erupted (∼1 km3 dense rock equivalent [DRE]), Sand Mountain volcanic field lava geochemistry indicates that erupted magmas were derived from at least two, and likely three, different magma sources. Single units erupted from one or more vents, and field data provide evidence of both vent migration and reoccupation. Overall, our study shows that mafic volcanism was clustered in space and time, involved both explosive and effusive behavior, and tapped several magma sources. These observations provide important insights on possible future hazards from mafic volcanism in the central Oregon Cascades.
THE DETROIT EXPOSURE AND AEROSOL RESEARCH STUDY (DEARS)
Field data collections for the Detroit Exposure and Aerosol Research Study (DEARS) have completed one-half of the planned study design. The DEARS is collecting personal, residential indoor, residential outdoor and central community monitoring data involving particulate matter, v...
McGrew, William C
2017-01-01
Field studies done over decades of wild chimpanzees in East, Central and West Africa have yielded impressive, cumulative findings in cultural primatology. Japanese primatologists have been involved in this advance from the outset, over a wide variety of topics. Here I review the origins and development of field studies of Pan troglodytes, then assess their progress based on analogy between cultural primatology and cultural anthropology, through four stages: natural history, ethnography, ethnology, and intuition. Then, I focus on six topics that continue to yield informative debate: technology, universals, nuanced variation, archaeology, applied primatology, and ecology. Finally, I offer a map of sites of field study of wild chimpanzees. It is clear that Japanese primatologists have made a significant contribution to East-West scientific exchange, especially at the field sites of Bossou and Mahale.
(TUCSON, AZ) SPATIAL ANALYSIS OF SUMMER 2004 DATA FROM DEARS
The Detroit Exposure and Aerosol Research Study (DEARS) represents a multi-year assessment field study involving summer and winter season collection of personal, residential indoor, residential outdoor and central community monitoring measurements.
Involving junior doctors in medical article publishing: is it an effective method of teaching?
Oyibo, Samson O
2017-01-01
Having peer-reviewed articles published in medical journals is important for career progression in many medical specialties. Despite this, only a minority of junior doctors have the skills in the area of medical article publishing. The aim of this study was to assess junior doctors' views concerning being involved in medical article publishing and whether they perceive involvement as an effective method of teaching. A cross-sectional survey was administered to a convenience sample of doctors who had been involved in medical article publishing. Questions concerned training and involvement in publishing as junior doctors, effects on education and training, is it an effective method of teaching and should publishing be part of their education and training program. Questions used the 5-point Likert scale. Of the 39 doctors, 37 (94.9%) doctors responded. Only one-third of respondents agreed that they had adequate training or involvement in medical article publishing during their undergraduate medical training. Many (78.4%) agreed that it was difficult to get published as a junior doctor. Publishing as a junior doctor improved knowledge about publishing, understanding of the topic and interest in the field of study for 92, 92 and 73% of respondents, respectively. Many (89%) agreed that publishing made them eager to publish more. Most (76%) agreed that it was likely to encourage interest in a postgraduate career in that field of study. A majority (92%) felt that involvement in medical article publishing is an effective method of teaching and it should be a part of the junior doctors' education and training program. Junior doctors feel that involvement in medical article publishing contributes to learning and education and is an effective method of teaching. This supports the need to incorporate such training into the junior doctors' education and training program.
Towards a General Model of Skills Involved in Sight Reading Music
ERIC Educational Resources Information Center
Kopiez, Reinhard; Lee, Ji In
2008-01-01
Sight reading is a functional skill which is essential for all musicians involved in particular fields of western classical music culture. In the last decade, expertise theory has shown that time spent on activities is a good predictor for later achievement in a domain. However, this study is based on the hypothesis that general and elementary…
Catalytic dimer nanomotors: continuum theory and microscopic dynamics.
Reigh, Shang Yik; Kapral, Raymond
2015-04-28
Synthetic chemically-powered motors with various geometries have potentially new applications involving dynamics on very small scales. Self-generated concentration and fluid flow fields, which depend on geometry, play essential roles in motor dynamics. Sphere-dimer motors, comprising linked catalytic and noncatalytic spheres, display more complex versions of such fields, compared to the often-studied spherical Janus motors. By making use of analytical continuum theory and particle-based simulations we determine the concentration fields, and both the complex structure of the near-field and point-force dipole nature of the far-field behavior of the solvent velocity field that are important for studies of collective motor motion. We derive the dependence of motor velocity on geometric factors such as sphere size and dimer bond length and, thus, show how to construct motors with specific characteristics.
Quench field sensitivity of two-particle correlation in a Hubbard model
Zhang, X. Z.; Lin, S.; Song, Z.
2016-01-01
Short-range interaction can give rise to particle pairing with a short-range correlation, which may be destroyed in the presence of an external field. We study the transition between correlated and uncorrelated particle states in the framework of one- dimensional Hubbard model driven by a field. We show that the long time-scale transfer rate from an initial correlated state to final uncorrelated particle states is sensitive to the quench field strength and exhibits a periodic behavior. This process involves an irreversible energy transfer from the field to particles, leading to a quantum electrothermal effect. PMID:27250080
Getting "Tillerized": Traits and Outcomes of Students in a Rural Community Field Placement
ERIC Educational Resources Information Center
Averett, Paige; Carawan, Lena; Burroughs, Courtney
2012-01-01
This qualitative study sought to reveal the traits and outcomes of students who completed a rural community organizing field placement. All stakeholders involved in the placement of students took part in a focus group and follow-up individual interviews. Findings suggest that students need to be open, flexible, self-directed, and maverick in…
In-situ culvert rehabilitation : synthesis study and field evaluation.
DOT National Transportation Integrated Search
2009-06-01
This synthesis study evaluated culvert rehabilitation (repair) methods involving trenchless technologies that may be appropriate for use in Utah. This report is not intended as a replacement for installation manuals provided by the manufacturers but ...
Field-based Metabolomics for Assessing Contaminated Surface Waters
Metabolomics is becoming well-established for studying chemical contaminant-induced alterations to normal biological function. For example, the literature contains a wealth of laboratory-based studies involving analysis of samples from organisms exposed to individual chemical tox...
Land utilization and water resource inventories over extended test sites
NASA Technical Reports Server (NTRS)
Hoffer, R. M.
1972-01-01
In addition to the work on the corn blight this year, several other analysis tests were completed which resulted in significant findings. These aspects are discussed as follows: (1) field spectral measurements of soil conditions; (2) analysis of extended test site data; this discussion involves three different sets of data analysis sequences; (3) urban land use analysis, for studying water runoff potentials; and (4) thermal data quality study, as an expansion of our water resources studies involving temperature calibration techniques.
Korlach, J.; Reichle, C.; Müller, T.; Schnelle, T.; Webb, W. W.
2005-01-01
The behavior of freestanding lipid bilayer membranes under the influence of dielectric force potentials was studied by trapping, holding, and rotating individual giant unilamellar vesicles (GUVs) inside dielectrophoretic microfield cages. Using laser scanning confocal microscopy and three-dimensional image reconstructions of GUVs labeled with fluorescent membrane probes, field strength and frequency-dependent vesicle deformations were observed which are explained by calculations of the dielectric force potentials inside the cage. Dynamical membrane properties under the influence of the field cage were studied by fluorescence correlation spectroscopy, circumventing potential artifacts associated with measurements involving GUV immobilization on support surfaces. Lipid transport could be accelerated markedly by the applied fields, aided by hydrodynamic fluid streaming which was also studied by fluorescence correlation spectroscopy. PMID:15863477
ERIC Educational Resources Information Center
Rockwood, Stacy F.
This paper outlines the procedures used at the University of Cincinnati for establishing a field based elementary teacher education program in the form of a field guide. The first step involves a meeting with university faculty to discuss the implications of such a program. Step two involves meeting with the elementary school principal and selling…
Interspecific aggression in hermatypic corals from Bermuda
NASA Astrophysics Data System (ADS)
Logan, A.
1984-11-01
Interspecific aggression between hermatypic corals on Bermudian reefs has been investigated by aquarium and field studies, the latter involving induced interactions, observations from 30 m-2 transects and random SCUBA traverses. Resultant hierarchies, constructed by ranking the abilities of species to damage competitors, show close similarities with each other and with the Jamaican hierarchy at the family level, notwithstanding some differences in the ranking of some species. Only 11% of natural-occurring interactions depart from the aquarium-derived results; in terms of species-pair combinations, 30% show partial or complete inversions from aquarium to field, with most changes involving species close together in the field hierarchy. Circular (intransitive) interactions occur mostly within a network of weakly-aggressive species in both aquarium- and fieldderived hierarchies. While number of potential interactions m-2 varies directly with density, frequency of aggression is positively correlated with coral diversity (species richness), while frequency of “no reactions” and conspecific fusion (combined) shows a correspondingly negative correlation with diversity. Frequency of aggression does not appear to be depth related. Comparison of aquarium and field hierarchies suggest that digestion by mesenterial filaments is the most important mechanism of aggression under natural conditions. Sweeper tentacle activity is the most likely cause of field reversals involving Madracis mirabilis and Montastrea cavernosa. Other factors, such as stress caused by seasonal environmental extremes, may be responsible for reversals or inconsistent behaviour in other species.
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2012 CFR
2012-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2011 CFR
2011-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2014 CFR
2014-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2010 CFR
2010-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
10 CFR 39.1 - Purpose and scope.
Code of Federal Regulations, 2013 CFR
2013-01-01
... of licensed materials including sealed sources, radioactive tracers, radioactive markers, and uranium... authorizing the use of licensed material in tracer studies involving multiple wells, such as field flooding...
2013–2014 national roadside study of alcohol and drug use by drivers : methodology.
DOT National Transportation Integrated Search
2016-07-01
This report describes the methodology for the National Roadside Study (NRS), a national field study to estimate the prevalence of alcohol-, drug-, and alcohol-plus-drug-involved driving primarily among nighttime weekend drivers, but also daytime Frid...
STUDY OF THE ARBUCKLE-SIMPSON AQUIFER
A study directed by the Oklahoma Water Resources Board and funded by the U.S. Bureau of Reclamation will investigate the hydrogeology of the Arbuckle-Simpson Aquifer in south-central Oklahoma. The five year study will involve field investigations including the installation of ne...
43 CFR 24.6 - Cooperative agreements.
Code of Federal Regulations, 2011 CFR
2011-10-01
... continued and encouraged. Appropriate topics for such cooperative agreements include but are not limited to... reintroduction and propagation; (3) Research and other field study programs including those involving the taking...
43 CFR 24.6 - Cooperative agreements.
Code of Federal Regulations, 2010 CFR
2010-10-01
... continued and encouraged. Appropriate topics for such cooperative agreements include but are not limited to... reintroduction and propagation; (3) Research and other field study programs including those involving the taking...
A study of girder deflections during bridge deck construction : final report.
DOT National Transportation Integrated Search
1971-01-01
Problems involved in obtaining the desired thickness of bridge decks were investigated. The study, which was limited to decks which were longitudinally screeded during construction, included (1) field measurements of the girder deflections during con...
Cosmological evolution of a tachyon-quintom model of dark energy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shi, Shang-Gang; Piao, Yun-Song; Qiao, Cong-Feng, E-mail: shishanggang06@mails.gucas.ac.cn, E-mail: yspiao@gucas.ac.cn, E-mail: qiaocf@gucas.ac.cn
2009-04-15
In this work we study the cosmological evolution of a dark energy model with two scalar fields, i.e. the tachyon and the phantom tachyon. This model enables the equation of state w to change from w > -1 to w < -1 in the evolution of the universe. The phase-space analysis for such a system with inverse square potentials shows that there exists a unique stable critical point, which has power-law solution. In this paper, we also study another form of tachyon-quintom model with two fields, which involves the interactions between both fields.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Koniges, A.E.; Craddock, G.G.; Schnack, D.D.
The purpose of the workshop was to assemble workers, both within and outside of the fusion-related computations areas, for discussion regarding the issues of dynamically adaptive gridding. There were three invited talks related to adaptive gridding application experiences in various related fields of computational fluid dynamics (CFD), and nine short talks reporting on the progress of adaptive techniques in the specific areas of scrape-off-layer (SOL) modeling and magnetohydrodynamic (MHD) stability. Adaptive mesh methods have been successful in a number of diverse fields of CFD for over a decade. The method involves dynamic refinement of computed field profiles in a waymore » that disperses uniformly the numerical errors associated with discrete approximations. Because the process optimizes computational effort, adaptive mesh methods can be used to study otherwise the intractable physical problems that involve complex boundary shapes or multiple spatial/temporal scales. Recent results indicate that these adaptive techniques will be required for tokamak fluid-based simulations involving the diverted tokamak SOL modeling and MHD simulations problems related to the highest priority ITER relevant issues.Individual papers are indexed separately on the energy data bases.« less
ERIC Educational Resources Information Center
Al Otaiba, Stephanie; Connor, Carol M.; Folsom, Jessica S.; Greulich, Luana; Meadows, Jane; Li, Zhi
2011-01-01
The purpose of this cluster-randomized control field trial was to examine whether kindergarten teachers could learn to differentiate classroom reading instruction using Individualized Student Instruction for Kindergarten (ISI-K) and to test the efficacy of differentiation on reading outcomes. The study involved 14 schools, 23 ISI-K (n = 305…
Changing the Logic of Practice: (Re)Drawing Boundaries, (Re)Defining Fields
ERIC Educational Resources Information Center
Smith, Wayne
2012-01-01
Background: The relationship between sport and exercise science (SES) and health and physical education (HPE) has been of interest to those of us involved in the general field of human movement studies in higher education for at least the last four decades. Purpose: The purpose of this research was to determine how the proposed merging of the…
The Impact of Field Trips and Family Involvement on Mental Models of the Desert Environment
ERIC Educational Resources Information Center
Judson, Eugene
2011-01-01
This study examined the mental models of the desert environment held by fourth- and seventh-grade students in the USA and whether those mental models could be affected by: (1) classroom field trips to a desert riparian preserve, and (2) interaction with family members at the same preserve. Results generally indicated that students in this study…
Development and field testing of a smartphone "App" for tinnitus management.
Henry, James A; Thielman, Emily; Zaugg, Tara; Kaelin, Christine; Choma, Christie; Chang, Bill; Hahn, Shira; Fuller, Bret
2017-10-01
This study's objective was to develop and test a smartphone app that supports learning and using coping skills for managing tinnitus. The app's content was based on coping skills that are taught as a part of progressive tinnitus management (PTM). The study involved three phases: (1) develop a prototype app and conduct usability testing; (2) conduct two focus groups to obtain initial feedback from individuals representing potential users; and (3) conduct a field study to evaluate the app, with three successive groups of participants. Participants were adults with bothersome tinnitus. For Phase 2, two focus groups were attended by a total of 17 participants. Phase 3 involved three consecutive rounds of participants: five from the focus groups followed by two rounds with 10 participants each who had not seen the app previously. In both the focus groups and field studies, participants responded favourably to the content. Certain features, however, were deemed too complex. Completion of this project resulted in the development and testing of the delivery of PTM coping skills via a smartphone app. This new approach has the potential to improve access to coping skills for those with bothersome tinnitus.
On the classification of elliptic foliations induced by real quadratic fields with center
NASA Astrophysics Data System (ADS)
Puchuri, Liliana; Bueno, Orestes
2016-12-01
Related to the study of Hilbert's infinitesimal problem, is the problem of determining the existence and estimating the number of limit cycles of the linear perturbation of Hamiltonian fields. A classification of the elliptic foliations in the projective plane induced by the fields obtained by quadratic fields with center was already studied by several authors. In this work, we devise a unified proof of the classification of elliptic foliations induced by quadratic fields with center. This technique involves using a formula due to Cerveau & Lins Neto to calculate the genus of the generic fiber of a first integral of foliations of these kinds. Furthermore, we show that these foliations induce several examples of linear families of foliations which are not bimeromorphically equivalent to certain remarkable examples given by Lins Neto.
Second level semi-degenerate fields in W_3 Toda theory: matrix element and differential equation
NASA Astrophysics Data System (ADS)
Belavin, Vladimir; Cao, Xiangyu; Estienne, Benoit; Santachiara, Raoul
2017-03-01
In a recent study we considered W_3 Toda 4-point functions that involve matrix elements of a primary field with the highest-weight in the adjoint representation of sl_3 . We generalize this result by considering a semi-degenerate primary field, which has one null vector at level two. We obtain a sixth-order Fuchsian differential equation for the conformal blocks. We discuss the presence of multiplicities, the matrix elements and the fusion rules.
2013-2014 National Roadside Study of alcohol and drug use by drivers : alcohol results.
DOT National Transportation Integrated Search
2016-12-01
This report describes the alcohol results from the 20132014 National Roadside Survey (NRS), a national field study to : estimate the prevalence of alcohol-, drug-, and alcohol-plus-drug-involved driving, primarily among nighttime weekend : drivers...
Velocity Field Measurements of Human Coughing Using Time Resolved Particle Image Velocimetry
NASA Astrophysics Data System (ADS)
Khan, T.; Marr, D. R.; Higuchi, H.; Glauser, M. N.
2003-11-01
Quantitative fluid mechanics analysis of human coughing has been carried out using new Time Resolved Particle Image Velocimetry (TRPIV). The study involves measurement of velocity vector time-histories and velocity profiles. It is focused on the average normal human coughing. Some work in the past on cough mechanics has involved measurement of flow rates, tidal volumes and sub-glottis pressure. However, data of unsteady velocity vector field of the exiting highly time-dependent jets is not available. In this study, human cough waveform data are first acquired in vivo using conventional respiratory instrumentation for various volunteers of different gender/age groups. The representative waveform is then reproduced with a coughing/breathing simulator (with or without a manikin) for TRPIV measurements and analysis. The results of this study would be useful not only for designing of indoor air quality and heating, ventilation and air conditioning systems, but also for devising means of protection against infectious diseases.
On the nature of photospheric magnetic fields beneath large coronal holes
NASA Technical Reports Server (NTRS)
Frankenthal, S.; Krieger, A. S.
1977-01-01
Proposed mechanisms for the formation of coronal holes are considered; the crucial issue appears to be whether the holes are permeated by rigidly rotating fields. It is suggested that the interaction between such a field and the differentially rotating, diffusive solar envelope will produce a fore aft asymmetry in the distribution of fields which emerge to the photosphere. An initial study is carried out in the context of an illustrative example, and the results indicate that the asymmetry may be observed for a certain range of parameters involving the properties of the solar envelope and the characteristic size of the emerging field pattern.
Continuation of superpave projects monitoring.
DOT National Transportation Integrated Search
2011-07-01
This study involved the continuous monitoring of material properties and field performance of : twelve Superpave project sections in Florida for the establishment of reasonable and effective mixture : design guidelines and criteria, the identificatio...
Central Field Index Versus Visual Field Index for Central Visual Function in Stable Glaucoma.
Rao, Aparna; Padhy, Debananda; Mudunuri, Harika; Roy, Avik K; Sarangi, Sarada P; Das, Gopinath
2017-01-01
To compare the variability of central field index (CFI) versus visual field index (VFI) in stable glaucoma with central fixation involvement. For this retrospective study, we identified multiple visual fields (VFs) of patients with repeatable central fixation involvement on Humphrey VFs (24-2 and 10-2 program) which were stable (clinically and on VFs) over a very short period of 2 to 3 months. The VFI and CFI were calculated as described in earlier reports. We graded the fields as early [mean deviation (MD)>-6 dB], moderate (-6.1 to -12 dB), and severe glaucoma (<-12 dB) based on MD on 24-2 program. The variability of CFI and VFI between visits and across different severity of glaucoma was compared. Relation of the divergence to field indices and clinical parameters were assessed. The intervisit difference for VFI was greater than CFI ranging from -4% to 9% versus -1% to 8% in early (P=0.9), -13% to 18% versus -6% to 17% (P=0.056) in moderate, and -21% to 19% versus -9% to 9% (P<0.001) in severe glaucoma. The CFI within each group had narrower range than VFI with maximum range in severe glaucoma (33% to 95%). The divergence of CFI from VFI started at MD 24-2 beyond (worse) -10 dB. This difference between CFI and VFI was associated significantly with number of points with P<1% on 24-2 (R=80.3%). CFI is less variable than VFI in stable eyes with fixation involvement especially in severe glaucoma indicating need for incorporating CFI calculation for monitoring advanced disease in eyes with central defects.
Electric-field enhanced performance in catalysis and solid-state devices involving gases
Blackburn, Bryan M.; Wachsman, Eric D.; Van Assche, IV, Frederick Martin
2015-05-19
Electrode configurations for electric-field enhanced performance in catalysis and solid-state devices involving gases are provided. According to an embodiment, electric-field electrodes can be incorporated in devices such as gas sensors and fuel cells to shape an electric field provided with respect to sensing electrodes for the gas sensors and surfaces of the fuel cells. The shaped electric fields can alter surface dynamics, system thermodynamics, reaction kinetics, and adsorption/desorption processes. In one embodiment, ring-shaped electric-field electrodes can be provided around sensing electrodes of a planar gas sensor.
Habitat Study. Transect Study. [Environmental Education Units.
ERIC Educational Resources Information Center
Minneapolis Independent School District 275, Minn.
These three documents outline teaching activities intended to involve children with their environment. Suggested preliminary studies to motivate and familiarize elementary school students with some characteristics of organisms and their physical environment are followed by descriptions of class activities that may be undertaken in the field.…
Continuation of superpave projects monitoring.
DOT National Transportation Integrated Search
2011-07-01
This study involved the continuous monitoring of material properties and field performance of twelve Superpave project sections in Florida for the establishment of reasonable and effective mixture design guidelines and criteria, the identification an...
Vanommeslaeghe, Kenno; Guvench, Olgun; MacKerell, Alexander D.
2014-01-01
Molecular Mechanics (MM) force fields are the methods of choice for protein simulations, which are essential in the study of conformational flexibility. Given the importance of protein flexibility in drug binding, MM is involved in most if not all Computational Structure-Based Drug Discovery (CSBDD) projects. This section introduces the reader to the fundamentals of MM, with a special emphasis on how the target data used in the parametrization of force fields determine their strengths and weaknesses. Variations and recent developments such as polarizable force fields are discussed. The section ends with a brief overview of common force fields in CSBDD. PMID:23947650
Finite element modeling of electromagnetic fields and waves using NASTRAN
NASA Technical Reports Server (NTRS)
Moyer, E. Thomas, Jr.; Schroeder, Erwin
1989-01-01
The various formulations of Maxwell's equations are reviewed with emphasis on those formulations which most readily form analogies with Navier's equations. Analogies involving scalar and vector potentials and electric and magnetic field components are presented. Formulations allowing for media with dielectric and conducting properties are emphasized. It is demonstrated that many problems in electromagnetism can be solved using the NASTRAN finite element code. Several fundamental problems involving time harmonic solutions of Maxwell's equations with known analytic solutions are solved using NASTRAN to demonstrate convergence and mesh requirements. Mesh requirements are studied as a function of frequency, conductivity, and dielectric properties. Applications in both low frequency and high frequency are highlighted. The low frequency problems demonstrate the ability to solve problems involving media inhomogeneity and unbounded domains. The high frequency applications demonstrate the ability to handle problems with large boundary to wavelength ratios.
Dehydrogenation involved Coulomb explosion of molecular C2H4FBr in an intense laser field
NASA Astrophysics Data System (ADS)
Pei, Minjie; Yang, Yan; Zhang, Jian; Sun, Zhenrong
2018-04-01
The dissociative double ionization (DDI) of molecular 1-fluo-2-bromoethane (FBE) in an intense laser field has been investigated by dc-slice imaging technology. The DDI channels involved with dehydrogenation are revealed and it's believed both the charge distribution and the bound character of real potential energy surfaces of parent ions play important roles in the dissociation process. The relationship between the potential energy surfaces of the precursor species and the photofragment ejection angles are also discussed and analyzed. Furthermore, the competition between the DDI channels has been studied and the Csbnd C bond cleavages dominate the DDI process at relative higher laser intensity.
The average motion of a charged particle in a dipole field
NASA Technical Reports Server (NTRS)
Chen, A. J.; Stern, D. P.
1974-01-01
The numerical representation of the average motion of a charged particle trapped in a geomagnetic field is developed. An assumption is made of the conservation of the first two adiabatic invariants where integration is along a field line between mirror points. The averaged motion also involved the parameters defining the magnetic field line to which the particle is attached. Methods involved in obtaining the motion in the equatorial plane of model magnetospheres are based on Hamiltonian functions. The restrictions imposed by the special nature of the dipole field are defined.
Spherical Ethylene/Air Diffusion Flames Subject to Concentric DC Electric Field in Microgravity
NASA Technical Reports Server (NTRS)
Yuan, Z. -G.; Hegde, U.; Faeth, G. M.
2001-01-01
It is well known that microgravity conditions, by eliminating buoyant flow, enable many combustion phenomena to be observed that are not possible to observe at normal gravity. One example is the spherical diffusion flame surrounding a porous spherical burner. The present paper demonstrates that by superimposing a spherical electrical field on such a flame, the flame remains spherical so that we can study the interaction between the electric field and flame in a one-dimensional fashion. Flames are susceptible to electric fields that are much weaker than the breakdown field of the flame gases owing to the presence of ions generated in the high temperature flame reaction zone. These ions and the electric current of the moving ions, in turn, significantly change the distribution of the electric field. Thus, to understand the interplay between the electric field and the flame is challenging. Numerous experimental studies of the effect of electric fields on flames have been reported. Unfortunately, they were all involved in complex geometries of both the flow field and the electric field, which hinders detailed study of the phenomena. In a one-dimensional domain, however, the electric field, the flow field, the thermal field and the chemical species field are all co-linear. Thus the problem is greatly simplified and becomes more tractable.
2007 National Roadside Survey of Alcohol and Drug Use by Drivers: Methodology
DOT National Transportation Integrated Search
2009-12-01
This report describes the methodology for the 2007 U.S. national field study to estimate the prevalence of alcohol-, drug-, and alcohol-and-drug-involved driving, primarily among nighttime weekend drivers, but also daytime Friday drivers. This study ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kavaliers, M.; Ossenkopp, K.P.
1990-02-26
One of the more consistent and dramatic effects of exposure to magnetic fields is the attenuation of morphine-induced analgesia. Results of previous studies have implicated alterations in calcium channel functioning and Ca{sup ++} flux in the mediation of these effects. It is generally accepted that Ca{sup ++}-activated-phospholipid-dependent protein kinase (Protein kinase C; PKC) plays an important role in relaying trans-membrane signaling in diverse Ca{sup ++} dependent cellular processes. In experiment 1 we observed that morphine-induced analgesia in the land snail, Cepaea nemoralis, as measured by the latency of an avoidance behavior to a warmed surface, was reduced by the PKCmore » activator, SC-9, and was enhanced by the PKC inhibitors, H-7 and H-9. In contrast, HA-10004, a potent inhibitor of other protein kinases, but only a very weak inhibitor of PKC, had no effect on morphine-induced analgesia. In experiment 2 exposure of snails for 30 minutes to a 1.0 gauss (rms) 60-Hz magnetic field reduced morphine-induced analgesia. This inhibitory effect of the magnetic field was reduced by the PKC inhibitors, H-7 and H-9, and was augmented by the PKC activator SC-9. These results suggest that: (i) PKC is involved in the modulation of morphine-induced analgesia and, (ii) the inhibitory effects of magnetic fields involve PKC.« less
Topological transformations of Hopf solitons in chiral ferromagnets and liquid crystals.
Tai, Jung-Shen B; Ackerman, Paul J; Smalyukh, Ivan I
2018-01-30
Liquid crystals are widely known for their facile responses to external fields, which forms a basis of the modern information display technology. However, switching of molecular alignment field configurations typically involves topologically trivial structures, although singular line and point defects often appear as short-lived transient states. Here, we demonstrate electric and magnetic switching of nonsingular solitonic structures in chiral nematic and ferromagnetic liquid crystals. These topological soliton structures are characterized by Hopf indices, integers corresponding to the numbers of times that closed-loop-like spatial regions (dubbed "preimages") of two different single orientations of rod-like molecules or magnetization are linked with each other. We show that both dielectric and ferromagnetic response of the studied material systems allow for stabilizing a host of topological solitons with different Hopf indices. The field transformations during such switching are continuous when Hopf indices remain unchanged, even when involving transformations of preimages, but discontinuous otherwise.
Perspectives on the Etiology of Violence in Later Life.
Mysyuk, Yuliya; Westendorp, Rudi G J; Lindenberg, Jolanda
2016-11-01
This article focuses on the development of a conceptual framework for explaining the etiology of violence in later life by various groups involved in the field of elder abuse. In this study, we explore this through eight focus groups with different professionals involved in the field of elder abuse and older persons themselves and in interviews with 35 experts in the field. Our findings show that dependency, vulnerability, power and control, social isolation, stress, and care burden play a central role in their explanations for the occurrence of violence in later life. The role of a history of violence in violence in later life is equivocal. The complexity and ambiguity of dependency and vulnerability, the notion of mutual dependency, and diverse attitudes and expectations toward them that arise with the aging process are distinct features of violence in later life that were found. © The Author(s) 2015.
Trends in Canadian Sociology Master's Theses in Relation to Research Ethics Review, 1995-2004.
van den Hoonaard, Will C
2006-12-01
THIS PAPER EXAMINES TRENDS IN CANADIAN Master's theses in sociology, 1995-2004, in the course the implementation of Canada's national research-ethics guidelines (2001), using data available from ProQuest Dissertations. While there has been no decline in the number of theses completed during this period, nearly 1/4 fewer theses now involve research participants. The proportion of theses using quantitative methods shows decline; theses using qualitative methods, however, have increased significantly over time. A closer inspection qualitative theses shows an impressive increase in the proportion of theses using interviews, while the decrease in theses using field work is even more dramatic, from 40% to 5%. The decrease of theses involving field work is particularly alarming for a significant segment of sociology that must derive its material mainly from field work. Data drawn from a larger study supplement the findings in this article.
Afshari, Daryoush; Moradian, Nasrin; Khalili, Majid; Razazian, Nazanin; Bostani, Arash; Hoseini, Jamal; Moradian, Mohamad; Ghiasian, Masoud
2016-10-01
Evidence is mounting that magnet therapy could alleviate the symptoms of multiple sclerosis (MS). This study was performed to test the effects of the pulsing magnetic fields on the paresthesia in MS patients. This study has been conducted as a randomized, double-blind, parallel-group clinical trial during the April 2012 to October 2013. The subjects were selected among patients referred to MS clinic of Imam Reza Hospital; affiliated to Kermanshah University of Medical Sciences, Iran. Sixty three patients with MS were included in the study and randomly were divided into two groups, 35 patients were exposed to a magnetic pulsing field of 4mT intensity and 15-Hz frequency sinusoidal wave for 20min per session 2 times per week over a period of 2 months involving 16 sessions and 28 patients was exposed to a magnetically inactive field (placebo) for 20min per session 2 times per week over a period of 2 months involving 16 sessions. The severity of paresthesia was measured by the numerical rating scale (NRS) at 30, 60days. The study primary end point was NRS change between baseline and 60days. The secondary outcome was NRS change between baseline and 30days. Patients exposing to magnetic field showed significant paresthesia improvement compared with the group of patients exposing to placebo. According to our results pulsed magnetic therapy could alleviate paresthesia in MS patients .But trials with more patients and longer duration are mandatory to describe long-term effects. Copyright © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bai, W; Zhang, R; Zhou, Z
Purpose: To compare elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer by a metaanalysis. Methods: Wanfang, CNKI, VIP, CBM databases, PubMed, Embase and Cochrane Library were searched to identify the controlled clinical trials of elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. The obtained data were analyzed using Stata 11.0. The difference between two groups was estimated by calculating the odds ratio (OR) with 95% confidence interval (95% CI). Results: A total of 12 controlled clinical trials involving 1095 esophagealmore » cancer patients, which were selected according to inclusion and exclusion criteria, were included in this meta-analysis. The meta-analysis showed that the elective nodal irradiation group reduced the rates of out-field failure comparing with involved-field irradiation group (OR=3.727, P=0.007). However, the rates of ≥grades 3 acute radiation pneumonitis and esophagitis were significantly higher in the elective nodal irradiation group than in the involved-field irradiation group (OR=0.348, P=0.001, OR=0.385, P=0.000). 1-, 2-, 3-year local control rates (OR=0.966, P=0.837, OR=0.946, P=0.781; OR=0.732P=0.098) and 1-, 3-, 5-year survival rates were similar in the two groups ( OR=0.966, P=0.837; OR=0.946, P=0.781; OR=0.732, P=0.098; OR=0.952, P=0.756; OR=1.149, P=0.422; OR=0.768, P=0.120). It is the same with the rates of distant metastasis (OR=0.986, P=0.937). Conclusion: Compared with involved-field irradiation, the elective nodal irradiation can reduce the rates of out-field failure for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. However, its advantage of local control and survival rates is not obvious and it increases the incidence of toxicities.« less
Fluctuations in Student Understanding of Newton's 3rd Law
NASA Astrophysics Data System (ADS)
Clark, Jessica W.; Sayre, Eleanor C.; Franklin, Scott V.
2010-10-01
We present data from a between-student study on student response to questions on Newton's Third Law given throughout the academic year. The study, conducted at Rochester Institute of Technology, involved students from the first and third of a three-quarter sequence. Construction of a response curve reveals subtle dynamics in student learning not captured by simple pre/post testing. We find a a significant positive effect from direct instruction, peaking at the end of instruction on forces, that diminishes by the end of the quarter. Two quarters later, in physics III, a significant dip in correct response occurs when instruction changes from the vector quantities of electric forces and fields to the scalar quantity of electric potential. Student response rebounds to its initial values, however, once instruction returns to the vector-based topics involving magnetic fields.
Peter R. Robichaud; Louise E. Ashmun; Randy B. Foltz; Charles G. Showers; J. Scott Groenier; Jennifer Kesler; Claire DeLeo; Mary Moore
2013-01-01
Guidelines for the production and aerial application of wood shred mulch as a post-fire hillslope treatment were developed from laboratory and field studies, several field operations, and the evaluations of professionals involved in those operations. At two early trial sites, the wood shred mulch was produced off-site and transported to the area of use. At the 2010...
Rapid burster - a weakly magnetized neutron star
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanawa, T.; Hirotani, K.; Kawai, N.
1989-01-01
The magnetic field of a neutron star involved in the rapid burster MXB 1730-335 is studied using a MHD instability model for type II bursts. It is suggested that the magnetic field on the surface is about 10 to the 8th G. The radius of the magnetosphere is estimated to be about 10 km. Observational evidence supporting this hypothesis is examined. 30 references.
Dharmarajan, Kavita V; Friedman, Debra L; Schwartz, Cindy L; Chen, Lu; FitzGerald, T J; McCarten, Kathleen M; Kessel, Sandy K; Iandoli, Matt; Constine, Louis S; Wolden, Suzanne L
2015-05-01
The study was designed to determine whether response-based therapy improves outcomes in intermediate-risk Hodgkin lymphoma. We examined patterns of first relapse in the study. From September 2002 to July 2010, 1712 patients <22 years old with stage I-IIA with bulk, I-IIAE, I-IIB, and IIIA-IVA with or without doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide were enrolled. Patients were categorized as rapid (RER) or slow early responders (SER) after 2 cycles of doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide (ABVE-PC). The SER patients were randomized to 2 additional ABVE-PC cycles or augmented chemotherapy with 21 Gy involved field radiation therapy (IFRT). RER patients were stipulated to undergo 2 additional ABVE-PC cycles and were then randomized to 21 Gy IFRT or no further treatment if complete response (CR) was achieved. RER without CR patients were non-randomly assigned to 21 Gy IFRT. Relapses were characterized without respect to site (initial, new, or both; and initial bulk or initial nonbulk), and involved field radiation therapy field (in-field, out-of-field, or both). Patients were grouped by treatment assignment (SER; RER/no CR; RER/CR/IFRT; and RER/CR/no IFRT). Summary statistics were reported. At 4-year median follow-up, 244 patients had experienced relapse, 198 of whom were fully evaluable for review. Those who progressed during treatment (n=30) or lacked relapse imaging (n=16) were excluded. The median time to relapse was 12.8 months. Of the 198 evaluable patients, 30% were RER/no CR, 26% were SER, 26% were RER/CR/no IFRT, 16% were RER/CR/IFRT, and 2% remained uncategorized. The 74% and 75% relapses involved initially bulky and nonbulky sites, respectively. First relapses rarely occurred at exclusively new or out-of-field sites. By contrast, relapses usually occurred at nodal sites of initial bulky and nonbulky disease. Although response-based therapy has helped define treatment for selected RER patients, it has not improved outcome for SER patients or facilitated refinement of IFRT volumes or doses. Copyright © 2015 Elsevier Inc. All rights reserved.
Eich, Hans Theodor; Müller, Rolf-Peter; Engenhart-Cabillic, Rita; Lukas, Peter; Schmidberger, Heinz; Staar, Susanne; Willich, Normann
2008-08-01
Radiotherapy of Hodgkin's Lymphoma has evolved from extended-field to involved-field (IF) radiotherapy reducing toxicity whilst maintaining high cure rates. Recent publications recommend further reduction in the radiation field to involved-node (IN) radiotherapy; however, this concept has never been tested in a randomized trial. The German Hodgkin Study Group aims to compare it with standard IF radiotherapy in their future HD17 trial. ALL patients must be examined by the radiation oncologist before the start of chemotherapy. At that time, patients must have complete staging CT scans. For patients with IN radiotherapy, a radiation planning CT before and after chemotherapy with patients in the treatment position is recommended. Fusion techniques, allowing the overlapping of the pre- and postchemotherapy CT scans, should be used. Usage of PET-CT scans with patients in the treatment position is recommended, whenever possible. The clinical target volume encompasses the initial volume of the Lymph node(s) before chemotherapy and incorporates the initial Location and extent of the disease taking the displacement of the normal tissues into account. The margin of the planning target volume should be 2 cm in axial and 3 cm in craniocaudal direction. If necessary, it can be reduced to 1-1.5 cm. To minimize Lung and cardiac toxicity, the target definition in the mediastinum is different. The concept of IN radiotherapy has been proposed as a means to further improve the therapeutic ratio by reducing the risk of radiation-induced toxicity, including second malignancies. Field sizes wiLL further decrease compared to IF radiotherapy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lord, J. S.; McKenzie, I.; Baker, P. J.
2011-07-15
The high magnetic field (HiFi) muon instrument at the ISIS pulsed neutron and muon source is a state-of-the-art spectrometer designed to provide applied magnetic fields up to 5 T for muon studies of condensed matter and molecular systems. The spectrometer is optimised for time-differential muon spin relaxation studies at a pulsed muon source. We describe the challenges involved in its design and construction, detailing, in particular, the magnet and detector performance. Commissioning experiments have been conducted and the results are presented to demonstrate the scientific capabilities of the new instrument.
Is the useful field of view a good predictor of at-fault crash risk in elderly Japanese drivers?
Sakai, Hiroyuki; Uchiyama, Yuji; Takahara, Miwa; Doi, Shun'ichi; Kubota, Fumiko; Yoshimura, Takayoshi; Tachibana, Atsumichi; Kurahashi, Tetsuo
2015-05-01
Although age-related decline in the useful field of view (UFOV) is well recognized as a risk factor for at-fault crash involvement in elderly drivers, there is still room to study its applicability to elderly Japanese drivers. In the current study, we thus examined the relationship between UFOV and at-fault crash history in an elderly Japanese population. We also explored whether potential factors that create awareness of reduced driving fitness could be a trigger for the self-regulation of driving in elderly drivers. We measured UFOV and at-fault crash history from 151 community-dwelling Japanese aged 60 years or older, and compared UFOV of at-fault crash-free and crash-involved drivers. We also measured self-evaluated driving style using a questionnaire. UFOV in crash-involved drivers was significantly lower than that in crash-free drivers. No significant difference was found in self-evaluated driving style between crash-free and crash-involved drivers. In addition, there was no significant association between UFOV and self-evaluated driving style. The present study showed that UFOV is a good predictor of at-fault crash risk in elderly Japanese drivers. Furthermore, our data imply that it might be difficult for elderly drivers to adopt appropriate driving strategies commensurate with their current driving competence. © 2014 Japan Geriatrics Society.
Ager, D D; Radul, J A
1992-12-01
The purpose of this study was to examine the effect of extremely low frequency (ELF) magnetic fields on the induction of genetic damage. In general, mutational studies involving ELF magnetic fields have proven negative. However, studies examining sister-chromatid exchange and chromosome aberrations have yielded conflicting results. In this study, we have examined whether 60-Hz magnetic fields are capable of inducing mutation or mitotic recombination in the yeast Saccharomyces cerevisiae. In addition we determined whether magnetic fields were capable of altering the genetic response of S. cerevisiae to UV (254 nm). We measured the frequencies of induced mutation, gene conversion and reciprocal mitotic crossing-over for exposures to magnetic fields alone (1 mT) or in combination with various UV exposures (2-50 J/m2). These experiments were performed using a repair-proficient strain (RAD+), as well as a strain of yeast (rad3) which is incapable of excising UV-induced thymine dimers. Magnetic field exposures did not induce mutation, gene conversion or reciprocal mitotic crossing-over in either of these strains, nor did the fields influence the frequencies of UV-induced genetic events.
Mycotoxin management studies by USDA "Ag Lab" in 2011
USDA-ARS?s Scientific Manuscript database
Studies again included several popcorn fields in 2011. The research has been redirected to investigate hybrid based and environmental influences on gene expression directly and indirectly involved in resistance to mycotoxin production, so milk stage undamaged and damaged ears have been saved in t...
ERIC Educational Resources Information Center
Andrews, David L.; Silk, Michael; Francombe, Jessica; Bush, Anthony
2013-01-01
As a field of study, kinesiology is realized in different places and locations as a multidisciplinary, interdisciplinary, and, very rarely, transdisciplinary project. In the words of the American Kinesiology Association, it is an academic discipline that involves the study of physical activity and its impact on health, society, and quality of…
Metabolomics is becoming well-established for studying chemical contaminant-induced alterations to normal biological function. For example, the literature contains a wealth of laboratory-based studies involving analysis of samples from organisms exposed to individual chemical tox...
Metabolomics has become well-established for studying chemical contaminant-induced alterations to normal biological function. For example, the literature contains a wealth of laboratory-based studies involving analysis of samples from organisms exposed to individual chemical toxi...
Foreign Language Study at Black Colleges.
ERIC Educational Resources Information Center
Turner, James S.
1992-01-01
Presents a discussion with James J. Davis, interim chairman of Howard University's Department of Romance Languages. Offers Davis' view that African-American students often are ambivalent about foreign language study and frequently prefer African to European languages. Describes how Davis became involved in the field. (SG)
Improving Lunar Exploration with Robotic Follow-up
NASA Technical Reports Server (NTRS)
Fong, T.; Bualat, M.; Deans, M.; Heggy E.; Helper, M.; Hodges, K.; Lee, P.
2011-01-01
We are investigating how augmenting human field work with subsequent robot activity can improve lunar exploration. Robotic "follow-up" might involve: completing geology observations; making tedious or long-duration measurements of a target site or feature; curating samples in-situ; and performing unskilled, labor-intensive work. To study this technique, we have begun conducting a series of lunar analog field tests at Haughton Crater (Canada). Motivation: In most field geology studies on Earth, explorers often find themselves left with a set of observations they would have liked to make, or samples they would have liked to take, if only they had been able to stay longer in the field. For planetary field geology, we can imagine mobile robots - perhaps teleoperated vehicles previously used for manned exploration or dedicated planetary rovers - being deployed to perform such follow-up activities [1].
Spontaneous Lorentz and diffeomorphism violation, massive modes, and gravity
NASA Astrophysics Data System (ADS)
Bluhm, Robert; Fung, Shu-Hong; Kostelecký, V. Alan
2008-03-01
Theories with spontaneous local Lorentz and diffeomorphism violation contain massless Nambu-Goldstone modes, which arise as field excitations in the minimum of the symmetry-breaking potential. If the shape of the potential also allows excitations above the minimum, then an alternative gravitational Higgs mechanism can occur in which massive modes involving the metric appear. The origin and basic properties of the massive modes are addressed in the general context involving an arbitrary tensor vacuum value. Special attention is given to the case of bumblebee models, which are gravitationally coupled vector theories with spontaneous local Lorentz and diffeomorphism violation. Mode expansions are presented in both local and spacetime frames, revealing the Nambu-Goldstone and massive modes via decomposition of the metric and bumblebee fields, and the associated symmetry properties and gauge fixing are discussed. The class of bumblebee models with kinetic terms of the Maxwell form is used as a focus for more detailed study. The nature of the associated conservation laws and the interpretation as a candidate alternative to Einstein-Maxwell theory are investigated. Explicit examples involving smooth and Lagrange-multiplier potentials are studied to illustrate features of the massive modes, including their origin, nature, dispersion laws, and effects on gravitational interactions. In the weak static limit, the massive mode and Lagrange-multiplier fields are found to modify the Newton and Coulomb potentials. The nature and implications of these modifications are examined.
Final Technical Report for Department of Energy award number DE-FG02-06ER54882, Revised
DOE Office of Scientific and Technical Information (OSTI.GOV)
Eggleston, Dennis L.
The research reported here involves studies of radial particle transport in a cylindrical, low-density Malmberg-Penning non-neutral plasma trap. The research is primarily experimental but involves careful comparisons to analytical theory and includes the results of a single-particle computer code. The transport is produced by applied electric fields that break the cylindrical symmetry of the trap, hence the term ``asymmetry-induced transport.'' Our computer studies have revealed the importance of a previously ignored class of particles that become trapped in the asymmetry potential. In many common situations these particles exhibit large radial excursions and dominate the radial transport. On the experimental side,more » we have developed new data analysis techniques that allowed us to determine the magnetic field dependence of the transport and to place empirical constraints on the form on the transport equation. Experiments designed to test the computer code results gave varying degrees of agreement with further work being necessary to understand the results. This work expands our knowledge of the varied mechanisms of cross-magnetic-field transport and should be of use to other workers studying plasma confinement.« less
NASA Astrophysics Data System (ADS)
Sushko, Gennady B.; Solov'yov, Ilia A.; Verkhovtsev, Alexey V.; Volkov, Sergey N.; Solov'yov, Andrey V.
2016-01-01
The concept of molecular mechanics force field has been widely accepted nowadays for studying various processes in biomolecular systems. In this paper, we suggest a modification for the standard CHARMM force field that permits simulations of systems with dynamically changing molecular topologies. The implementation of the modified force field was carried out in the popular program MBN Explorer, and, to support the development, we provide several illustrative case studies where dynamical topology is necessary. In particular, it is shown that the modified molecular mechanics force field can be applied for studying processes where rupture of chemical bonds plays an essential role, e.g., in irradiation- or collision-induced damage, and also in transformation and fragmentation processes involving biomolecular systems. Contribution to the Topical Issue "COST Action Nano-IBCT: Nano-scale Processes Behind Ion-Beam Cancer Therapy", edited by Andrey V. Solov'yov, Nigel Mason, Gustavo Garcia and Eugene Surdutovich.
Geochemistry and origin of regional dolomites
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanson, G.N.; Meyers, W.J.
1992-01-01
This grant supports research on the origins and geochemical aspects of regional dolomites. Eight graduate students are involved in research on dolomite allowing a diverse range of studies. This report outlines their work in the field. (JL)
Ferrando, Nicolas; Lachet, Véronique; Boutin, Anne
2010-07-08
Ketone and aldehyde molecules are involved in a large variety of industrial applications. Because they are mainly present mixed with other compounds, the prediction of phase equilibrium of mixtures involving these classes of molecules is of first interest particularly to design and optimize separation processes. The main goal of this work is to propose a transferable force field for ketones and aldehydes that allows accurate molecular simulations of not only pure compounds but also complex mixtures. The proposed force field is based on the anisotropic united-atoms AUA4 potential developed for hydrocarbons, and it introduces only one new atom, the carbonyl oxygen. The Lennard-Jones parameters of this oxygen atom have been adjusted on saturated thermodynamic properties of both acetone and acetaldehyde. To simulate mixtures, Monte Carlo simulations are carried out in a specific pseudoensemble which allows a direct calculation of the bubble pressure. For polar mixtures involved in this study, we show that this approach is an interesting alternative to classical calculations in the isothermal-isobaric Gibbs ensemble. The pressure-composition diagrams of polar + polar and polar + nonpolar binary mixtures are well reproduced. Mutual solubilities as well as azeotrope location, if present, are accurately predicted without any empirical binary interaction parameters or readjustment. Such result highlights the transferability of the proposed force field, which is an essential feature toward the simulation of complex oxygenated mixtures of industrial interest.
NASA Astrophysics Data System (ADS)
Illangasekare, T. H.; Sakaki, T.; Smits, K. M.; Limsuwat, A.; Terrés-Nícoli, J. M.
2008-12-01
Understanding the dynamics of soil moisture distribution near the ground surface is of interest in various applications involving land-atmospheric interaction, evaporation from soils, CO2 leakage from carbon sequestration, vapor intrusion into buildings, and land mine detection. Natural soil heterogeneity in combination with water and energy fluxes at the soil surface creates complex spatial and temporal distributions of soil moisture. Even though considerable knowledge exists on how soil moisture conditions change in response to flux and energy boundary conditions, emerging problems involving land atmospheric interactions require the quantification of soil moisture variability both at high spatial and temporal resolutions. The issue of up-scaling becomes critical in all applications, as in general, field measurements are taken at sparsely distributed spatial locations that require assimilation with measurements taken using remote sensing technologies. It is our contention that the knowledge that will contribute to both improving our understanding of the fundamental processes and practical problem solution cannot be obtained easily in the field due to a number of constraints. One of these basic constraints is the inability to make measurements at very fine spatial scales at high temporal resolutions in naturally heterogeneous field systems. Also, as the natural boundary conditions at the land/atmospheric interface are not controllable in the field, even in pilot scale studies, the developed theories and tools cannot be validated for the diversity of conditions that could be expected in the field. Intermediate scale testing using soil tanks packed to represent different heterogeneous test configurations provides an attractive and cost effective alternative to investigate a class of problems involving the shallow unsaturated zone. In this presentation, we will discuss the advantages and limitations of studies conducted in both two and three dimensional intermediate scale test systems together with instrumentation and measuring techniques. The features and capabilities of a new coupled porous media/climate wind tunnel test system that allows for the study of near surface unsaturated soil moisture conditions under climate boundary conditions will also be presented with the goal of exploring opportunities to use such a facility to study some of the multi-scale problems in the near surface unsaturated zone.
On the Vertigo Due to Static Magnetic Fields
Mian, Omar S.; Li, Yan; Antunes, Andre; Glover, Paul M.; Day, Brian L.
2013-01-01
Vertigo is sometimes experienced in and around MRI scanners. Mechanisms involving stimulation of the vestibular system by movement in magnetic fields or magnetic field spatial gradients have been proposed. However, it was recently shown that vestibular-dependent ocular nystagmus is evoked when stationary in homogenous static magnetic fields. The proposed mechanism involves Lorentz forces acting on endolymph to deflect semicircular canal (SCC) cupulae. To investigate whether vertigo arises from a similar mechanism we recorded qualitative and quantitative aspects of vertigo and 2D eye movements from supine healthy adults (n = 25) deprived of vision while pushed into the 7T static field of an MRI scanner. Exposures were variable and included up to 135s stationary at 7T. Nystagmus was mainly horizontal, persisted during long-exposures with partial decline, and reversed upon withdrawal. The dominant vertiginous perception with the head facing up was rotation in the horizontal plane (85% incidence) with a consistent direction across participants. With the head turned 90 degrees in yaw the perception did not transform into equivalent vertical plane rotation, indicating a context-dependency of the perception. During long exposures, illusory rotation lasted on average 50 s, including 42 s whilst stationary at 7T. Upon withdrawal, perception re-emerged and reversed, lasting on average 30 s. Onset fields for nystagmus and perception were significantly correlated (p<.05). Although perception did not persist as long as nystagmus, this is a known feature of continuous SSC stimulation. These observations, and others in the paper, are compatible with magnetic-field evoked-vertigo and nystagmus sharing a common mechanism. With this interpretation, response decay and reversal upon withdrawal from the field, are due to adaptation to continuous vestibular input. Although the study does not entirely exclude the possibility of mechanisms involving transient vestibular stimulation during movement in and out of the bore, we argue these are less likely. PMID:24205304
On the vertigo due to static magnetic fields.
Mian, Omar S; Li, Yan; Antunes, Andre; Glover, Paul M; Day, Brian L
2013-01-01
Vertigo is sometimes experienced in and around MRI scanners. Mechanisms involving stimulation of the vestibular system by movement in magnetic fields or magnetic field spatial gradients have been proposed. However, it was recently shown that vestibular-dependent ocular nystagmus is evoked when stationary in homogenous static magnetic fields. The proposed mechanism involves Lorentz forces acting on endolymph to deflect semicircular canal (SCC) cupulae. To investigate whether vertigo arises from a similar mechanism we recorded qualitative and quantitative aspects of vertigo and 2D eye movements from supine healthy adults (n = 25) deprived of vision while pushed into the 7T static field of an MRI scanner. Exposures were variable and included up to 135s stationary at 7T. Nystagmus was mainly horizontal, persisted during long-exposures with partial decline, and reversed upon withdrawal. The dominant vertiginous perception with the head facing up was rotation in the horizontal plane (85% incidence) with a consistent direction across participants. With the head turned 90 degrees in yaw the perception did not transform into equivalent vertical plane rotation, indicating a context-dependency of the perception. During long exposures, illusory rotation lasted on average 50 s, including 42 s whilst stationary at 7T. Upon withdrawal, perception re-emerged and reversed, lasting on average 30 s. Onset fields for nystagmus and perception were significantly correlated (p<.05). Although perception did not persist as long as nystagmus, this is a known feature of continuous SSC stimulation. These observations, and others in the paper, are compatible with magnetic-field evoked-vertigo and nystagmus sharing a common mechanism. With this interpretation, response decay and reversal upon withdrawal from the field, are due to adaptation to continuous vestibular input. Although the study does not entirely exclude the possibility of mechanisms involving transient vestibular stimulation during movement in and out of the bore, we argue these are less likely.
Acadia National Park ITS field operational test : key informant interviews
DOT National Transportation Integrated Search
2003-03-01
This document reflects the ideas and opinions of a group of key informants and stakeholders involved in the Field Operational Test of ITS components in and around Acadia National Park from 1999 through 2002. The stakeholders were involved in the plan...
Long-term behavior of GFRP reinforced panels after eight years of field exposure.
DOT National Transportation Integrated Search
2014-06-01
Since 1998, Missouri S&T/University of Missouri-Rolla investigators have been involved in more than 25 bridge repairs and/or new : bridge construction involving composite materials. To date, many of these projects have demonstrated reliable field per...
Charged Compact Boson Stars in a Theory of Massless Scalar Field
NASA Astrophysics Data System (ADS)
Kumar, Sanjeev
2018-05-01
In this work we present some new results obtained in a study of the phase diagram of charged compact boson stars in a theory involving a complex scalar field with a conical potential coupled to a U(1) gauge field and gravity. We obtain new bifurcation points in this model. We present a detailed discussion of the various regions of the phase diagram with respect to the bifurcation points. The theory is seen to contain rich physics in a particular domain of the phase diagram.
Risk-Based, Hypothesis-Driven Framework for Hydrological Field Campaigns with Case Studies
NASA Astrophysics Data System (ADS)
Harken, B.; Rubin, Y.
2014-12-01
There are several stages in any hydrological modeling campaign, including: formulation and analysis of a priori information, data acquisition through field campaigns, inverse modeling, and prediction of some environmental performance metric (EPM). The EPM being predicted could be, for example, contaminant concentration or plume travel time. These predictions often have significant bearing on a decision that must be made. Examples include: how to allocate limited remediation resources between contaminated groundwater sites or where to place a waste repository site. Answering such questions depends on predictions of EPMs using forward models as well as levels of uncertainty related to these predictions. Uncertainty in EPM predictions stems from uncertainty in model parameters, which can be reduced by measurements taken in field campaigns. The costly nature of field measurements motivates a rational basis for determining a measurement strategy that is optimal with respect to the uncertainty in the EPM prediction. The tool of hypothesis testing allows this uncertainty to be quantified by computing the significance of the test resulting from a proposed field campaign. The significance of the test gives a rational basis for determining the optimality of a proposed field campaign. This hypothesis testing framework is demonstrated and discussed using various synthetic case studies. This study involves contaminated aquifers where a decision must be made based on prediction of when a contaminant will arrive at a specified location. The EPM, in this case contaminant travel time, is cast into the hypothesis testing framework. The null hypothesis states that the contaminant plume will arrive at the specified location before a critical amount of time passes, and the alternative hypothesis states that the plume will arrive after the critical time passes. The optimality of different field campaigns is assessed by computing the significance of the test resulting from each one. Evaluating the level of significance caused by a field campaign involves steps including likelihood-based inverse modeling and semi-analytical conditional particle tracking.
Chapel, Paul
1996-01-01
The U.S. Geological Survey (USGS) is known throughout the world for conducting quality scientific investigation is hydrologic environments. Proper and consistent field techniques have been an integral part of this good research. Over the past few decades, the USGS has developed and published detailed, standard protocols for conducting studies in most aspects of the hydrologic environment. These protocols have been published in a number of diverse documents. The wealth of information contained in these diverse documents can benefit other scientists in industry, government, and academia that are involved in conducting hydrologic studies. Scientists at the USGS have brought together many of the most important of the field protocols in a user-friendly, graphical-interfaced field manual that will be useful in both the field and in the office. This electronic field manual can assist hydrologists and other scientists in conducting and documenting their field activities in a manner that is recognized standard throughout the hydrologic community.
DOT National Transportation Integrated Search
1994-02-01
The Crescent Project element of the HELP Program is a bi-national multi-jurisdictional : cooperative research and demonstration initiative involving the public and private sectors in an : application of advanced technologies for the creation of an in...
CRUDE OIL BIOREMEDIATION: THE AMERICAN EXPERIENCE (PRESENTATION)
This is a state-of-the-art extended abstract presentation summary of the outputs from the oil spill program over the last 11 years. It summarizes the results of 3 field studies involving intentional releases of crude oil: the Delaware study in 1994 (sandy beach), the St. Lawrence...
Electron beam therapy with coil-generated magnetic fields.
Nardi, Eran; Barnea, Gideon; Ma, Chang-Ming
2004-06-01
This paper presents an initial study on the issues involved in the practical implementation of the use of transverse magnetic fields in electron beam therapy. By using such magnetic fields the dose delivered to the tumor region can increase significantly relative to that deposited to the healthy tissue. Initially we calculated the magnetic fields produced by the Helmholtz coil and modified Helmholtz coil configurations. These configurations, which can readily be used to generate high intensity magnetic fields, approximate the idealized magnetic fields studied in our previous publications. It was therefore of interest to perform a detailed study of the fields produced by these configurations. Electron beam dose distributions for 15 MeV electrons were calculated using the ACCEPTM code for a 3T transverse magnetic field produced by the modified Helmholtz configuration. The dose distribution was compared to those obtained with no magnetic field. The results were similar to those obtained in our previous work, where an idealized step function magnetic field was used and a 3T field was shown to be the optimal field strength. A simpler configuration was also studied in which a single external coil was used to generate the field. Electron dose distributions are also presented for a given geometry and given magnetic field strength using this configuration. The results indicate that this method is more difficult to apply to radiotherapy due to its lack of symmetry and its irregularity. For the various configurations dealt with here, a major problem is the need to shield the magnetic field in the beam propagation volume, a topic that must be studied in detail.
An Introduction to Early Childhood Studies. Second Edition
ERIC Educational Resources Information Center
Maynard, Trisha, Ed.; Thomas, Nigel, Ed.
2009-01-01
The second edition of this best-selling textbook provides students and practitioners with a broad introduction to, and critical analysis of, the main theories and issues within the field of early childhood studies. The book adopts a multi-disciplinary approach and pulls together all the key themes involved in the study of young children and…
Data Bases in Vocational Education and Training. The European Scene.
ERIC Educational Resources Information Center
European Centre for the Development of Vocational Training, Berlin (West Germany).
This study of public access databases in vocational education and training was conducted in the European Economic Community (EEC). Principal sources for the study were a survey sent to practitioners in eight countries; country studies on France, Greece, Italy, and the United Kingdom; and field work involving visits to Belgium, the Netherlands,…
Meet EPA Engineer Gayle Hagler, Ph.D.
Gayle develops innovative ways to measure air pollution through field studies, data analysis and computer modeling. She is deeply involved with a research program that explores near-roadway air pollution sources and other local air pollution emissions
Thresholds and Targeting Actions Research
The project will implement novel field and laboratory-based studies, state-of-the-art modeling, and other research syntheses toward these goals and toward decreasing scientific uncertainty related to nutrient management. The key research areas involve improved nutrient indicator ...
Performance of a pile-supported embankment.
DOT National Transportation Integrated Search
2006-01-01
The purpose of this study was to evaluate the field performance of the first pile-supported highway embankment constructed in Virginia. The project involved construction of an approach to the new bridge over the Mattaponi River, replacing the existin...
Demonstration of motion control of ZrO2 microparticles in uniform/non-uniform electric field
NASA Astrophysics Data System (ADS)
Onishi, Genki; Trung, Ngo Nguyen Chi; Matsutani, Naoto; Nakayama, Tadachika; Suzuki, Tsuneo; Suematsu, Hisayuki; Niihara, Koichi
2018-02-01
This study aims to elucidate the mechanism that drives dielectric microparticles under an electric field. The driving of microstructures is affected by various electrical phenomena occurring at the same time such as surface potential, polarization, and electrostatic force. It makes the clarification of the driving mechanism challenging. A simple experimental system was used to observe the behavior of spherical ZrO2 microparticles in a nonaqueous solution under an electric field. The results suggest that the mechanism that drives the ZrO2 microparticles under an electric field involved the combination of an electric image force, a gradient force, and the contact charging phenomenon. A method is proposed to control the motion of micro- and nanostructures in further study and applications.
Haraldseid, Cecilie; Friberg, Febe; Aase, Karina
2016-01-01
Policy initiatives and an increasing amount of the literature within higher education both call for students to become more involved in creating their own learning. However, there is a lack of studies in undergraduate nursing education that actively involve students in developing such learning material with descriptions of the students' roles in these interactive processes. Explorative qualitative study, using data from focus group interviews, field notes and student notes. The data has been subjected to qualitative content analysis. Active student involvement through an iterative process identified five different learning needs that are especially important to the students: clarification of learning expectations, help to recognize the bigger picture, stimulation of interaction, creation of structure, and receiving context- specific content. The iterative process involvement of students during the development of new technological learning material will enhance the identification of important learning needs for students. The use of student and teacher knowledge through an adapted co-design process is the most optimal level of that involvement.
The Plate Boundary Observatory Student Field Assistant Program in Southern California
NASA Astrophysics Data System (ADS)
Seider, E. L.
2007-12-01
Each summer, UNAVCO hires students as part of the Plate Boundary Observatory (PBO) Student Field Assistant Program. PBO, the geodetic component of the NSF-funded EarthScope project, involves the reconnaissance, permitting, installation, documentation, and maintenance of 880 permanent GPS stations in five years. During the summer 2007, nine students from around the US and Puerto Rico were hired to assist PBO engineers during the busy summer field season. From June to September, students worked closely with PBO field engineers to install and maintain permanent GPS stations in all regions of PBO, including Alaska. The PBO Student Field Assistant Program provides students with professional hands-on field experience as well as continuing education in the geosciences. It also gives students a glimpse into the increasing technologies available to the science community, the scope of geophysical research utilizing these technologies, and the field techniques necessary to complete this research. Students in the PBO Field Assistant Program are involved in all aspects of GPS support, including in-warehouse preparation and in-field installations and maintenance. Students are taught practical skills such as drilling, wiring, welding, hardware configuration, documentation, and proper field safety procedures needed to construct permanent GPS stations. These real world experiences provide the students with technical and professional skills that are not always available to them in a classroom, and will benefit them greatly in their future studies and careers. The 2007 summer field season in Southern California consisted of over 35 GPS permanent station installations. To date, the Southern California region of PBO has installed over 190 GPS stations. This poster presentation will highlight the experiences gained by the Southern California student field assistants, while supporting PBO- Southern California GPS installations in the Mohave Desert and the Inyo National Forest.
Molecular Dynamics Simulations, Challenges and Opportunities: A Biologist's Prospective.
Kumari, Indu; Sandhu, Padmani; Ahmed, Mushtaq; Akhter, Yusuf
2017-08-30
Molecular dynamics (MD) is a computational technique which is used to study biomolecules in virtual environment. Each of the constituent atoms represents a particle and hence the biomolecule embodies a multi-particle mechanical system analyzed within a simulation box during MD analysis. The potential energies of the atoms are explained by a mathematical expression consisting of different forces and space parameters. There are various software and force fields that have been developed for MD studies of the biomolecules. MD analysis has unravelled the various biological mechanisms (protein folding/unfolding, protein-small molecule interactions, protein-protein interactions, DNA/RNA-protein interactions, proteins embedded in membrane, lipid-lipid interactions, drug transport etc.) operating at the atomic and molecular levels. However, there are still some parameters including torsions in amino acids, carbohydrates (whose structure is extended and not well defined like that of proteins) and single stranded nucleic acids for which the force fields need further improvement, although there are several workers putting in constant efforts in these directions. The existing force fields are not efficient for studying the crowded environment inside the cells, since these interactions involve multiple factors in real time. Therefore, the improved force fields may provide the opportunities for their wider applications on the complex biosystems in diverse cellular conditions. In conclusion, the intervention of MD in the basic sciences involving interdisciplinary approaches will be helpful for understanding many fundamental biological and physiological processes at the molecular levels that may be further applied in various fields including biotechnology, fisheries, sustainable agriculture and biomedical research. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Corn and sorghum studies by the usda "Ag Lab" in 2012
USDA-ARS?s Scientific Manuscript database
Studies again included several popcorn fields in 2012. The research has been redirected to investigate environmental influences on gene expression directly and indirectly involved in resistance to mycotoxin production, so milk stage undamaged and damaged ears have been saved in the freezer for the g...
Outdoor Activities for Environmental Studies.
ERIC Educational Resources Information Center
Knapp, Clifford E.
This booklet is a compilation of field-tested outdoor activities introducing basic projects for small group or individualized study in monitoring certain aspects of the environment. Its purpose is to provide teachers with new ways to involve children directly in meaningful and developmental learning activities and to help students become more…
Values-Based Leadership: College Leaders' Perceptions on Maintaining Values in Decision Making
ERIC Educational Resources Information Center
Buckner, Ramona K.
2013-01-01
The purpose of this study was to explore college leaders' experiences negotiating conflicts between personal and organizational values. This qualitative study utilized symbolic interactionism and involved interviews with five college campus leaders from various institutions. Analysis of interviews, observations, field notes and artifacts revealed…
Lessons from the Field: Participatory Action Research in a Family Research Project.
ERIC Educational Resources Information Center
Robison, Dorothy; Krauss, Marty Wyngaarden
2003-01-01
This paper describes development of a study that includes participatory action research, specifically the establishment of a family advisory committee. The study involved a survey of Massachusetts families of children with disabilities. Suggestions for establishing and integrating the committee into the research enterprise are offered, as are…
Difficult Knowledge and Social Studies (Teacher) Education
ERIC Educational Resources Information Center
Garrett, H. James
2010-01-01
Social studies education is a field in which those involved--teachers and students--encounter what can be called "difficult knowledge". Difficult knowledge is a theoretical construct suggesting that when an individual encounters representations of social and historical trauma in a learning situation there exists a host of emotional and pedagogical…
Evolution of Observation: Implementing Programmatic Change
ERIC Educational Resources Information Center
Bender-Slack, Delane A.; Young, Teresa
2013-01-01
In the study reported, we examine the evolution of preservice teacher observation, focusing on the essential nature of observation to preservice teachers' learning about teaching while in the field. The study was 3 years long, and it involved 79 preservice teachers during semester-long language arts methods courses in early childhood and…
76 FR 31943 - Notice of Proposed Information Collection Requests
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-02
..., Evaluation and Policy Development Type of Review: New. Title of Collection: Analysis of State Bullying Laws... bullying laws and policies. The field data collection portion of the study will involve case studies conducted in 24 school sites nationwide to document state and local implementation of anti-bullying laws and...
Studies of nonlinear femtosecond pulse propagation in bulk materials
NASA Astrophysics Data System (ADS)
Eaton, Hilary Kaye
2000-10-01
Femtosecond pulse lasers are finding widespread application in a variety of fields including medical research, optical switching and communications, plasma formation, high harmonic generation, and wavepacket formation and control. As the number of applications for femtosecond pulses increases, so does the need to fully understand the linear and nonlinear processes involved in propagating these pulses through materials under various conditions. Recent advances in pulse measurement techniques, such as frequency-resolved optical gating (FROG), allow measurement of the full electric field of the pulse and have made detailed investigations of short- pulse propagation effects feasible. In this thesis, I present detailed experimental studies of my work involving nonlinear propagation of femtosecond pulses in bulk media. Studies of plane-wave propagation in fused silica extend the SHG form of FROG from a simple pulse diagnostic to a useful method of interrogating the nonlinear response of a material. Studies of nonlinear propagation are also performed in a regime where temporal pulse splitting occurs. Experimental results are compared with a three- dimensional nonlinear Schrödinger equation. This comparison fuels the development of a more complete model for pulse splitting. Experiments are also performed at peak input powers above those at which pulse splitting is observed. At these higher intensities, a broadband continuum is generated. This work presents a detailed study of continuum behavior and power loss as well as the first near-field spatial- spectral measurements of the generated continuum light. Nonlinear plane-wave propagation of short pulses in liquids is also investigated, and a non-instantaneous nonlinearity with a surprisingly short response time of 10 fs is observed in methanol. Experiments in water confirm that this effect in methanol is indeed real. Possible explanations for the observed effect are discussed and several are experimentally rejected. This thesis applies FROG as a powerful tool for science and not just a useful pulse diagnostic technique. Studies of three-dimensional propagation provide an in-depth understanding of the processes involved in femtosecond pulse splitting. In addition, the experimental investigations of continuum generation and pulse propagation in liquids provide new insights into the possible processes involved and should provide a useful comparison for developing theories.
[Roots of the preinstitucionalization of professional nursing in Recife (PE), Brazil--1922-1938].
Abrõ, Fátima Maria da Silva; de Almeida, Maria Cecília Puntel
2007-01-01
This historical-social study aimed to understand the roots of the preinstitutionalization of Professional nursing in a given organizational field. We considered the origins of nursing in the political-social context of the First Republic, Second Republic, beginning of the Estado Novo and the interwar period. The study rests on institutional theory and Bourdieu's notion of field. As an institutional environment, the Hospital do Centenário was a demarcation point for the future organizational field of professional nursing. In the period from 1922 to 1938, an emerging organizational field was evidenced, in which the presence of Public Health and the State stand out. Public Health Visitants and Sanitary Educators appear as the forerunners for the professional bases of nursing. We observed the fight of agents involved in the formation of this field, creating and developing alliances and strategies.
NASA Astrophysics Data System (ADS)
Oyeyemi, Kehinde D.; Olowokere, Mary T.; Aizebeokhai, Ahzegbobor P.
2017-12-01
The evaluation of economic potential of any hydrocarbon field involves the understanding of the reservoir lithofacies and porosity variations. This in turns contributes immensely towards subsequent reservoir management and field development. In this study, integrated 3D seismic data and well log data were employed to assess the quality and prospectivity of the delineated reservoirs (H1-H5) within the OPO field, western Niger Delta using a model-based seismic inversion technique. The model inversion results revealed four distinct sedimentary packages based on the subsurface acoustic impedance properties and shale contents. Low acoustic impedance model values were associated with the delineated hydrocarbon bearing units, denoting their high porosity and good quality. Application of model-based inverted velocity, density and acoustic impedance properties on the generated time slices of reservoirs also revealed a regional fault and prospects within the field.
Dimensional reduction of the Standard Model coupled to a new singlet scalar field
NASA Astrophysics Data System (ADS)
Brauner, Tomáš; Tenkanen, Tuomas V. I.; Tranberg, Anders; Vuorinen, Aleksi; Weir, David J.
2017-03-01
We derive an effective dimensionally reduced theory for the Standard Model augmented by a real singlet scalar. We treat the singlet as a superheavy field and integrate it out, leaving an effective theory involving only the Higgs and SU(2) L × U(1) Y gauge fields, identical to the one studied previously for the Standard Model. This opens up the possibility of efficiently computing the order and strength of the electroweak phase transition, numerically and nonperturbatively, in this extension of the Standard Model. Understanding the phase diagram is crucial for models of electroweak baryogenesis and for studying the production of gravitational waves at thermal phase transitions.
Magnetic Nanoparticle Drug Carriers and their Study by Quadrupole Magnetic Field-Flow Fractionation
Williams, P. Stephen; Carpino, Francesca; Zborowski, Maciej
2009-01-01
Magnetic nanoparticle drug carriers continue to attract considerable interest for drug targeting in the treatment of cancers and other pathological conditions. The efficient delivery of therapeutic levels of drug to a target site while limiting nonspecific, systemic toxicity requires optimization of the drug delivery materials, the applied magnetic field, and the treatment protocol. The history and current state of magnetic drug targeting is reviewed. While initial studies involved micron-sized and larger carriers, and work with these microcarriers continues, it is the sub-micron carriers or nanocarriers that are of increasing interest. An aspect of magnetic drug targeting using nanoparticle carriers that has not been considered is then addressed. This aspect involves the variation in the magnetic properties of the nanocarriers. Quadrupole magnetic field-flow fractionation (QMgFFF) is a relatively new technique for characterizing magnetic nanoparticles. It is unique in its capability of determining the distribution in magnetic properties of a nanoparticle sample in suspension. The development and current state of this technique is also reviewed. Magnetic nanoparticle drug carriers have been found by QMgFFF analysis to be highly polydisperse in their magnetic properties, and the strength of response of the particles to magnetic field gradients is predicted to vary by orders of magnitude. It is expected that the least magnetic fraction of a formulation will contribute the most to systemic toxicity, and the depletion of this fraction will result in a more effective drug carrying material. A material that has a reduced systemic toxicity will allow higher doses of cytotoxic drugs to be delivered to the tumor with reduced side effects. Preliminary experiments involving a novel method of refining a magnetic nanoparticle drug carrier to achieve this result are described. QMgFFF is used to characterize the refined and unrefined material. PMID:19591456
DOE Office of Scientific and Technical Information (OSTI.GOV)
van Poelgeest, F.; Niko, H.; Modwid, A.R.
1991-03-01
Shell Expro and Koninklijke/Shell E and P Laboratorium (KSEPL) have been engaged in a multidisciplinary effort to determine the water flood residual oil saturation (ROS) in two principal reservoirs of the Cormorant oil field in the U.K. sector of the North Sea. Data acquisition included special coring and testing. The study, which involved new reservoir-engineering and petrophysical techniques, was aimed at establishing consistent ROS values. This paper reports that reservoir-engineering work centered on reservoir-condition corefloods in the relative-permeability-at-reservoir-conditions (REPARC) apparatus, in which restoration of representative wettability condition was attempted with the aging technique. Aging results in a consistent reduction ofmore » water-wetness of all core samples. The study indicated that ROS values obtained on aged cores at water throughputs of at least 5 PV represented reservoir conditions. The petrophysical part of the study involved ROS estimation from sponge-core analysis and log evaluation.« less
User involvement in adolescents' mental healthcare: protocol for a systematic review.
Viksveen, Petter; Bjønness, Stig Erlend; Berg, Siv Hilde; Cardenas, Nicole Elizabeth; Game, Julia Rose; Aase, Karina; Storm, Marianne
2017-12-21
User involvement has become a growing importance in healthcare. The United Nations state that adolescents have a right to be heard, and user involvement in healthcare is a legal right in many countries. Some research provides an insight into the field of user involvement in somatic and mental healthcare for adults, but little is known about user involvement in adolescents' mental healthcare, and no overview of the existing research evidence exists. The aim of this systematic review is to provide an overview of existing research reporting on experiences with and the effectiveness and safety issues associated with user involvement for adolescents' mental healthcare at the individual and organisational level. A systematic literature search and assessment of published research in the field of user involvement in adolescents' mental healthcare will be carried out. Established guidelines will be used for data extraction (Cochrane Collaboration guidelines, Strengthening the Reporting of Observational studies in Epidemiology and Critical Appraisal Skills Programme (CASP)), critical appraisal (Cochrane Collaboration guidelines and Pragmatic-Explanatory Continuum Indicator Summary) and reporting of results (Preferred Reporting Items for Systematic reviews and Meta-Analyses, Consolidated Standards of Reporting Trials and CASP). Confidence in the research evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. Adolescents are included as coresearchers for the planning and carrying out of this systematic review. This systematic review will provide an overview of the existing research literature and thereby fill a knowledge gap. It may provide various stakeholders, including decision-makers, professionals, individuals and their families, with an overview of existing knowledge in an underexplored field of research. Ethics approval is not required for this systematic review as we are not collecting primary data. The results will be published in a peer-reviewed journal and at conference presentations and will be shared with stakeholder groups. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Electrochemical formation of field emitters
Bernhardt, Anthony F.
1999-01-01
Electrochemical formation of field emitters, particularly useful in the fabrication of flat panel displays. The fabrication involves field emitting points in a gated field emitter structure. Metal field emitters are formed by electroplating and the shape of the formed emitter is controlled by the potential imposed on the gate as well as on a separate counter electrode. This allows sharp emitters to be formed in a more inexpensive and manufacturable process than vacuum deposition processes used at present. The fabrication process involves etching of the gate metal and the dielectric layer down to the resistor layer, and then electroplating the etched area and forming an electroplated emitter point in the etched area.
Pulsation research during the IMS. [International Magnetospheric Study
NASA Technical Reports Server (NTRS)
Hughes, W. J.
1982-01-01
After describing the development status of the field of magnetic pulsations in 1975, before the initiation of the International Magnetospheric Study (IMS), attention is given to the IMS's novel observational results and an attempt is made to identify the most effective research methods employed. It is found that the most fruitful work involved small-scale collaboration between a few individuals or a few groups possessing complementary data sets. Consideration is restricted to research on the long period pulsations which can be broadly classified as field line resonances. Recommendations are made for future research efforts.
Bio-insecticides and mating disruption in cranberries
USDA-ARS?s Scientific Manuscript database
Surveys of native entomopathogenic nematodes in Wisconsin have produced a new bio-insecticide involving two particular nematode species (Oscheius onirici and Heterorhabditis georgiana). In field studies, these nematodes have shown high virulence against flea beetles; in the laboratory, these nematod...
Production and evaluation of sugar cane fiber geotextiles : report 2 : field testing.
DOT National Transportation Integrated Search
1997-03-01
Prior research involved the production and laboratory testing of sugar cane fiber geotextiles for soil erosion control. Comparative preliminary studies were conducted on test slopes to determine slope stability, in horticulture plots to determine gra...
Immune Response to Electromagnetic Fields through Cybernetic Modeling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Godina-Nava, J. J.; Segura, M. A. Rodriguez; Cadena, S. Reyes
We study the optimality of the humoral immune response through a mathematical model, which involves the effect of electromagnetic fields over the large lymphocytes proliferation. Are used the so called cybernetic variables in the context of the matching law of microeconomics or mathematical psychology, to measure the large lymphocytes population and to maximize the instantaneous antibody production rate in time during the immunologic response in order to most efficiently inactivate the antigen.
ERIC Educational Resources Information Center
Wong, Suk-Ying; And Others
This report is intended to serve as a general reference for people either new to the field or involved in planning and decision-making in the field of distance education, specifically in Asia and the Pacific region. Volume II contains data from 15 countries: the Republic of Korea, Laos, Malaysia, Maldives, Myanmar, Nepal, New Zealand, Pakistan,…
ERIC Educational Resources Information Center
Remmen, Kari Beate; Frøyland, Merethe
2013-01-01
Our study explores how students apply geoscientific knowledge learned in the classroom to phenomena in a field setting. This was investigated by collecting video data from an ordinary high school context in Norway involving one teacher and a class of 17 high school students. We analyzed how the students learned rock identification and relative…
Immune Response to Electromagnetic Fields through Cybernetic Modeling
NASA Astrophysics Data System (ADS)
Godina-Nava, J. J.; Segura, M. A. Rodríguez; Cadena, S. Reyes; Sierra, L. C. Gaitán
2008-08-01
We study the optimality of the humoral immune response through a mathematical model, which involves the effect of electromagnetic fields over the large lymphocytes proliferation. Are used the so called cybernetic variables in the context of the matching law of microeconomics or mathematical psychology, to measure the large lymphocytes population and to maximize the instantaneous antibody production rate in time during the immunologic response in order to most efficiently inactivate the antigen.
Analyzing neural responses with vector fields.
Buneo, Christopher A
2011-04-15
Analyzing changes in the shape and scale of single cell response fields is a key component of many neurophysiological studies. Typical analyses of shape change involve correlating firing rates between experimental conditions or "cross-correlating" single cell tuning curves by shifting them with respect to one another and correlating the overlapping data. Such shifting results in a loss of data, making interpretation of the resulting correlation coefficients problematic. The problem is particularly acute for two dimensional response fields, which require shifting along two axes. Here, an alternative method for quantifying response field shape and scale based on correlation of vector field representations is introduced. The merits and limitations of the methods are illustrated using both simulated and experimental data. It is shown that vector correlation provides more information on response field changes than scalar correlation without requiring field shifting and concomitant data loss. An extension of this vector field approach is also demonstrated which can be used to identify the manner in which experimental variables are encoded in studies of neural reference frames. Copyright © 2011 Elsevier B.V. All rights reserved.
Electrodynamics in One Dimension: Radiation and Reflection
ERIC Educational Resources Information Center
Asti, G.; Coisson, R.
2011-01-01
Problems involving polarized plane waves and currents on sheets perpendicular to the wavevector involve only one component of the fields, so it is possible to discuss electrodynamics in one dimension. Taking for simplicity linearly polarized sinusoidal waves, we can derive the field emitted by currents (analogous to dipole radiation in three…
ERIC Educational Resources Information Center
Fox, G. Thomas, Jr.
1978-01-01
Suggests that there exist great potential and much professional support for practitioner involvement (teachers, students, and administrators) in generating knowledge (creating new understandings of what is occurring in our experience and why) from field experience and that the probable consequences noted when practitioners become involved in…
49 CFR 579.23 - Reporting requirements for manufacturers of 5,000 or more motorcycles annually.
Code of Federal Regulations, 2012 CFR
2012-10-01
... claims, consumer complaints, warranty claims, and field reports which involve the systems and components..., consumer complaints, warranty claims, or field reports, respectively, that involves the systems or components or fire indicated by the code. If an underlying property damage claim, consumer complaint...
49 CFR 579.23 - Reporting requirements for manufacturers of 5,000 or more motorcycles annually.
Code of Federal Regulations, 2014 CFR
2014-10-01
... claims, consumer complaints, warranty claims, and field reports which involve the systems and components..., consumer complaints, warranty claims, or field reports, respectively, that involves the systems or components or fire indicated by the code. If an underlying property damage claim, consumer complaint...
49 CFR 579.23 - Reporting requirements for manufacturers of 5,000 or more motorcycles annually.
Code of Federal Regulations, 2013 CFR
2013-10-01
... claims, consumer complaints, warranty claims, and field reports which involve the systems and components..., consumer complaints, warranty claims, or field reports, respectively, that involves the systems or components or fire indicated by the code. If an underlying property damage claim, consumer complaint...
Gifted Girls and Nonmathematical Aspirations: A Longitudinal Case Study of Two Gifted Korean Girls
ERIC Educational Resources Information Center
Lee, Kyeong Hwa; Sriraman, Bharath
2012-01-01
In this longitudinal study of two gifted Korean girls, experiences with early admittance into a gifted program are charted alongside their family and societal experiences that ultimately influenced their career choices in nonmathematical fields. The 8-year-long qualitative study involved extensive interviews with the two gifted girls and their…
Case Studies in Science Education, Booklet X: Vortex as Harbinger.
ERIC Educational Resources Information Center
Hoke, Gordon
This booklet is the eleventh of a series of 16 booklets that together describe and present findings for a study which involved field observations and a survey of science teaching and learning in American public schools during the school year 1976-77. The study was undertaken to provide the National Science Foundation with a portrayal of current…
ERIC Educational Resources Information Center
van Lankveld, T.; Schoonenboom, J.; Kusurkar, R. A.; Volman, M.; Beishuizen, J.; Croiset, G.
2017-01-01
Beginning medical teachers often see themselves as doctors or researchers rather than as teachers. Using both figured worlds theory and dialogical self theory, this study explores how beginning teachers in the field of undergraduate medical education integrate the teacher role into their identity. A qualitative study was performed, involving 18…
Alternation between Work and Education. A Study of Educational Leave of Absence at Enterprise Level.
ERIC Educational Resources Information Center
Organisation for Economic Cooperation and Development, Paris (France). Centre for Educational Research and Innovation.
The study reported here involves six countries (Germany, Italy, Yugoslavia, United Kingdom, United States, and Sweden) and focuses on the ways in which those who are actively employed have access to opportunities to alternate education and training with their employment. The first chapter discusses the study structure and defines the field covered…
NASA Astrophysics Data System (ADS)
Shibayeva, Marina; Serebryakova, Yelena; Shalnev, Oleg
2017-10-01
Growing demand to increase the investment volume in modernization and development projects for transport infrastructure define the urgency of the current study. The amount of private sector investments in the field is insufficient to implement the projects for road construction due to their significant capital intensity and long payoff period. The implementation of social significant infrastructure projects on the principles of public-private partnership is one of the key strategic directions of growth for transport facilities. The authors come up with a concept and methodology for modeling the investment and innovation activity in the transport facility construction. Furthermore, there is developed a model to find the balance between public and private sector investments in implementing construction projects for transport infrastructure with involvement of PPP (further - public-private partnership). The suggested concepts aim to improve the efficiency rate of the investment and innovation activity in the field of transport facility construction on the basis of public and private sectors collaboration.
NASA Astrophysics Data System (ADS)
Martini, Lara; Boll, Diego I. R.; Fojón, Omar A.
2017-08-01
Basic reactions involving water molecules are essential to understand the interaction between radiation and the biological tissue because living cells are composed mostly by water. Therefore, the knowledge of ionization of the latter is crucial in many domains of Biology and Physics. So, we study theoretically the photoionization of water molecules by extreme ultraviolet attopulse trains assisted by lasers in the near-infrared range. We use a separable Coulomb-Volkov model in which the temporal evolution of the system can be divided into three stages allowing spatial and temporal separation for the Coulomb and Volkov final state wavefunctions. First, we analyze photoelectron angular distributions for different delays between the attopulse train and the assistant laser field. We compare our results for water and Ne atoms as they belong to the same isoelectronic series. Moreover, we contrast our calculations with previous theoretical and experimental work for Ar atoms due to the similarities of the orbitals involved in the reaction. Second, we study the effect of varying the relative orientations of the attopulse and laser field polarizations and we compare our predictions with other theories and experiments. We expect these studies contribute to the improvement of polarization experiments and the development of the attopulse trains and assistant laser fields technologies. Finally, we hope our work promote progress on the control of the chemical reactivity of water molecules since this could be useful in different fields such as radiobiology and medical physics.
Foreign exchange market as a lattice gauge theory
NASA Astrophysics Data System (ADS)
Young, K.
1999-10-01
A simple model of the foreign exchange market is exactly a lattice gauge theory. Exchange rates are the exponentials of gauge potentials defined on spatial links while interest rates are related to gauge potentials on temporal links. Arbitrage opportunities are given by nonzero values of the gauge-invariant field tensor or curvature defined on closed loops. Arbitrage opportunities involving cross-rates at one time are "magnetic fields," while arbitrage opportunities involving future contracts are "electric fields."
Stakeholder involvement in water management: necessity or luxury?
Morrison, K
2003-01-01
Stakeholder involvement in water management is widely recognized as an important component of the design and implementation of sustainable water management initiatives. Despite this, there remains a deep-rooted resistance to the widespread implementation of programs to prioritize such involvement (as witnessed by, for example, the low priority given to the public involvement element of the European Union Water Framework Directive). This paper addresses the issue of stakeholder involvement by first confronting the fact that it is not a water issue, per se. Such diverse fields as economics, agriculture, public health, pollution prevention, business and education have also identified stakeholder involvement as a difficult but necessary component of successful action in their fields. For the water sector, the issue of stakeholder involvement as either a necessity for sustainable water management, or a luxury to be used to complement traditional approaches, is discussed.
Could the electroweak scale be linked to the large scale structure of the Universe?
NASA Technical Reports Server (NTRS)
Chakravorty, Alak; Massarotti, Alessandro
1991-01-01
We study a model where the domain walls are generated through a cosmological phase transition involving a scalar field. We assume the existence of a coupling between the scalar field and dark matter and show that the interaction between domain walls and dark matter leads to an energy dependent reflection mechanism. For a simple Yakawa coupling, we find that the vacuum expectation value of the scalar field is theta approx. equals 30GeV - 1TeV, in order for the model to be successful in the formation of large scale 'pancake' structures.
Direct Simulation of Reentry Flows with Ionization
NASA Technical Reports Server (NTRS)
Carlson, Ann B.; Hassan, H. A.
1989-01-01
The Direct Simulation Monte Carlo (DSMC) method is applied in this paper to the study of rarefied, hypersonic, reentry flows. The assumptions and simplifications involved with the treatment of ionization, free electrons and the electric field are investigated. A new method is presented for the calculation of the electric field and handling of charged particles with DSMC. In addition, a two-step model for electron impact ionization is implemented. The flow field representing a 10 km/sec shock at an altitude of 65 km is calculated. The effects of the new modeling techniques on the calculation results are presented and discussed.
FLOCCULATION-FLOTATION AIDS FOR TREATMENT OF COMBINED SEWER OVERFLOWS
The objectives of this study were to investigate the flocculation/flotation characteristics of combined sewer overflow through laboratory and field testing. The concept involves the introduction of chemicals and buoyant flotation aids into the overflow and the subsequent cofloccu...
Evaluation of the intelligent cruise control system : volume 1 : study results
DOT National Transportation Integrated Search
1999-10-01
The Intelligent Cruise Control (ICC) system evaluation was based on an ICC Field Operational Test (FOT) performed in Michigan. The FOT involved 108 volunteers recruited to drive ten ICC-equipped Chrysler Concordes. Testing was initiated in July 1996 ...
Field Projects with Rivers for Introductory Physical-Geology Laboratories.
ERIC Educational Resources Information Center
Cordua, William S.
1983-01-01
Discusses exercises using a river for the study of river processes and landforms. Although developed for college, they can be adapted for other levels. Exercises involve discharge measurement, flood prediction, and application of the Hjulstrom diagram to river sediments. (JN)
Media Anthropology: A Theoretical Framework
ERIC Educational Resources Information Center
Eiselein, E. B.; Topper, Martin
1976-01-01
Media anthropology, a diverse field, has involved nearly all the major subdisciplines of anthropology and most of the major media in five different areas of interaction: the study of media, reaching the public, gathering data, teaching with media, and applied media anthropology. (NQ)
Albuquerque, Kevin; Patel, Mona; Liotta, Margaret; Harkenrider, Matthew; Guo, Rong; Small, William; Ronald, Potkul
2016-05-01
This study aimed to report on long-term effectiveness of involved field radiation therapy (IFRT) in the salvage of localized recurrent ovarian cancer (ROC). A retrospective analysis of 27 patients with a diagnosis of epithelial ovarian cancer who received tumor volume-directed IFRT for localized extraperitoneal recurrences (either as consolidation after cytoreductive surgery (CRS) or as attempted salvage if unresectable) forms the basis of this report. All patients were heavily pretreated with multiple chemotherapy regimens. Involved field radiation therapy was primarily with external beam (median dose, 50.4 Gy). Local recurrence-free survival (LRFS) was defined as freedom from in-field recurrences and was considered as a measure of effectiveness of radiotherapy. Statistical analyses evaluated association between disease-free survival, overall survival, LRFS, and various prognostic factors. Comparison was also made with a similar but unmatched cohort with localized recurrences salvaged by additional chemotherapy instead of local therapies (NIFRT group). Of 27 patients, 17 had optimal CRS before RT. The actuarial survival at 5 and 10 years (in parenthesis) from date of radiation were LRFS (70% and 60%), overall survival (30% and 19%), and disease-free survival (33% and 20%). None of the NIFRT patients survived beyond 5 years from initiation of salvage chemotherapy. Long-term follow-up in this selected series confirmed the benefit of IFRT (±CRS) in localized ROC. Chemotherapy salvage in a similar NIFRT group was not equivalent, suggesting a role for locoregional therapies in selected patients with ROC.
Planning and setting objectives in field studies: Chapter 2
Fisher, Robert N.; Dodd, C. Kenneth
2016-01-01
This chapter enumerates the steps required in designing and planning field studies on the ecology and conservation of reptiles, as these involve a high level of uncertainty and risk. To this end, the chapter differentiates between goals (descriptions of what one intends to accomplish) and objectives (the measurable steps required to achieve the established goals). Thus, meeting a specific goal may require many objectives. It may not be possible to define some of them until certain experiments have been conducted; often evaluations of sampling protocols are needed to increase certainty in the biological results. And if sampling locations are fixed and sampling events are repeated over time, then both study-specific covariates and sampling-specific covariates should exist. Additionally, other critical design considerations for field study include obtaining permits, as well as researching ethics and biosecurity issues.
A free-electron laser in a uniform magnetic field
NASA Technical Reports Server (NTRS)
Ride, S. K.; Colson, W. B.
1979-01-01
The study shows that a free-electron laser can operate in a uniform, longitudinal magnetic field. The fully relativistic Lorentz force equations are examined and solved order by order in a radiation field strength to obtain analytic expressions for the electron trajectory and energy as functions of initial electron position within a wavelength of light. Analytic expressions for the longitudinal and transverse bunching and for laser gain are found. The bunching of this laser process is compared to the bunching processes involved in (1) a Stanford free-electron laser and (2) a cyclotron maser. The results received can be useful in exploring light amplification in astrophysical magnetic fields, the magnetosphere, and in laboratory devices.
Pierre, Th
2013-01-01
In a new toroidal laboratory plasma device including a poloidal magnetic field created by an internal circular conductor, the confinement efficiency of the magnetized plasma and the turbulence level are studied in different situations. The plasma density is greatly enhanced when a sufficiently large poloidal magnetic field is established. Moreover, the instabilities and the turbulence usually found in toroidal devices without sheared magnetic field lines are suppressed by the finite rotational transform. The particle confinement time is estimated from the measurement of the plasma decay time. It is compared to the Bohm diffusion time and to the value predicted by different diffusion models, in particular neoclassical diffusion involving trapped particles.
Practical management of sudden cardiac arrest on the football field.
Kramer, Efraim Benjamin; Botha, Martin; Drezner, Jonathan; Abdelrahman, Yasser; Dvorak, Jiri
2012-12-01
Sudden cardiac arrest (SCA) remains a tragic occurrence on the football field. The limits of preparticipation cardiovascular screening make it compulsory that prearranged emergency medical services be available at all football matches to immediately respond to any collapsed player. Management of SCA involves prompt recognition, immediate cardiopulmonary resuscitation (CPR) and early defibrillation. Any football player who collapses without contact with another player or obstacle should be regarded as being in SCA until proven otherwise. An automated external defibrillator (AED), or manual defibrillator if an AED is not available, should be immediately accessible on the field during competitions. This study presents guidelines for a practical and systematic approach to the management of SCA on the football field.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dharmarajan, Kavita V.; Friedman, Debra L.; Schwartz, Cindy L.
2015-05-01
Purpose: The study was designed to determine whether response-based therapy improves outcomes in intermediate-risk Hodgkin lymphoma. We examined patterns of first relapse in the study. Patients and Methods: From September 2002 to July 2010, 1712 patients <22 years old with stage I-IIA with bulk, I-IIAE, I-IIB, and IIIA-IVA with or without doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide were enrolled. Patients were categorized as rapid (RER) or slow early responders (SER) after 2 cycles of doxorubicin, bleomycin, vincristine, etoposide, prednisone, and cyclophosphamide (ABVE-PC). The SER patients were randomized to 2 additional ABVE-PC cycles or augmented chemotherapy with 21 Gy involved field radiationmore » therapy (IFRT). RER patients were stipulated to undergo 2 additional ABVE-PC cycles and were then randomized to 21 Gy IFRT or no further treatment if complete response (CR) was achieved. RER without CR patients were non-randomly assigned to 21 Gy IFRT. Relapses were characterized without respect to site (initial, new, or both; and initial bulk or initial nonbulk), and involved field radiation therapy field (in-field, out-of-field, or both). Patients were grouped by treatment assignment (SER; RER/no CR; RER/CR/IFRT; and RER/CR/no IFRT). Summary statistics were reported. Results: At 4-year median follow-up, 244 patients had experienced relapse, 198 of whom were fully evaluable for review. Those who progressed during treatment (n=30) or lacked relapse imaging (n=16) were excluded. The median time to relapse was 12.8 months. Of the 198 evaluable patients, 30% were RER/no CR, 26% were SER, 26% were RER/CR/no IFRT, 16% were RER/CR/IFRT, and 2% remained uncategorized. The 74% and 75% relapses involved initially bulky and nonbulky sites, respectively. First relapses rarely occurred at exclusively new or out-of-field sites. By contrast, relapses usually occurred at nodal sites of initial bulky and nonbulky disease. Conclusion: Although response-based therapy has helped define treatment for selected RER patients, it has not improved outcome for SER patients or facilitated refinement of IFRT volumes or doses.« less
Studying the Effect of Deposition Conditions on the Performance and Reliability of MEMS Gas Sensors
Sadek, Khaled; Moussa, Walied
2007-01-01
In this paper, the reliability of a micro-electro-mechanical system (MEMS)-based gas sensor has been investigated using Three Dimensional (3D) coupled multiphysics Finite Element (FE) analysis. The coupled field analysis involved a two-way sequential electrothermal fields coupling and a one-way sequential thermal-structural fields coupling. An automated substructuring code was developed to reduce the computational cost involved in simulating this complicated coupled multiphysics FE analysis by up to 76 percent. The substructured multiphysics model was then used to conduct a parametric study of the MEMS-based gas sensor performance in response to the variations expected in the thermal and mechanical characteristics of thin films layers composing the sensing MEMS device generated at various stages of the microfabrication process. Whenever possible, the appropriate deposition variables were correlated in the current work to the design parameters, with good accuracy, for optimum operation conditions of the gas sensor. This is used to establish a set of design rules, using linear and nonlinear empirical relations, which can be utilized in real-time at the design and development decision-making stages of similar gas sensors to enable the microfabrication of these sensors with reliable operation.
Studying marine stratus with large eddy simulation
NASA Technical Reports Server (NTRS)
Moeng, Chin-Hoh
1990-01-01
Data sets from field experiments over the stratocumulus regime may include complications from larger scale variations, decoupled cloud layers, diurnal cycle, or entrainment instability, etc. On top of the already complicated turbulence-radiation-condensation processes within the cloud-topped boundary layer (CTBL), these complexities may sometimes make interpretation of the data sets difficult. To study these processes, a better understanding is needed of the basic processes involved in the prototype CTBL. For example, is cloud top radiative cooling the primary source of the turbulent kinetic energy (TKE) within the CTBL. Historically, laboratory measurements have played an important role in addressing the turbulence problems. The CTBL is a turbulent field which is probably impossible to generate in laboratories. Large eddy simulation (LES) is an alternative way of 'measuring' the turbulent structure under controlled environments, which allows the systematic examination of the basic physical processes involved. However, there are problems with the LES approach for the CTBL. The LES data need to be consistent with the observed data. The LES approach is discussed, and results are given which provide some insights into the simulated turbulent flow field. Problems with this approach for the CTBL and information from the FIRE experiment needed to justify the LES results are discussed.
Magnetic-field-induced DNA strand breaks in brain cells of the rat.
Lai, Henry; Singh, Narendra P
2004-01-01
In previous research, we found that rats acutely (2 hr) exposed to a 60-Hz sinusoidal magnetic field at intensities of 0.1-0.5 millitesla (mT) showed increases in DNA single- and double-strand breaks in their brain cells. Further research showed that these effects could be blocked by pretreating the rats with the free radical scavengers melatonin and N-tert-butyl-alpha-phenylnitrone, suggesting the involvement of free radicals. In the present study, effects of magnetic field exposure on brain cell DNA in the rat were further investigated. Exposure to a 60-Hz magnetic field at 0.01 mT for 24 hr caused a significant increase in DNA single- and double-strand breaks. Prolonging the exposure to 48 hr caused a larger increase. This indicates that the effect is cumulative. In addition, treatment with Trolox (a vitamin E analog) or 7-nitroindazole (a nitric oxide synthase inhibitor) blocked magnetic-field-induced DNA strand breaks. These data further support a role of free radicals on the effects of magnetic fields. Treatment with the iron chelator deferiprone also blocked the effects of magnetic fields on brain cell DNA, suggesting the involvement of iron. Acute magnetic field exposure increased apoptosis and necrosis of brain cells in the rat. We hypothesize that exposure to a 60-Hz magnetic field initiates an iron-mediated process (e.g., the Fenton reaction) that increases free radical formation in brain cells, leading to DNA strand breaks and cell death. This hypothesis could have an important implication for the possible health effects associated with exposure to extremely low-frequency magnetic fields in the public and occupational environments. PMID:15121512
Phoretic Force Measurement for Microparticles Under Microgravity Conditions
NASA Technical Reports Server (NTRS)
Davis, E. J.; Zheng, R.
1999-01-01
This theoretical and experimental investigation of the collisional interactions between gas molecules and solid and liquid surfaces of microparticles involves fundamental studies of the transfer of energy, mass and momentum between gas molecules and surfaces. The numerous applications include particle deposition on semiconductor surfaces and on surfaces in combustion processes, containerless processing, the production of nanophase materials, pigments and ceramic precursors, and pollution abatement technologies such as desulfurization of gaseous effluents from combustion processes. Of particular emphasis are the forces exerted on microparticles present in a nonuniform gas, that is, in gaseous surroundings involving temperature and concentration gradients. These so-called phoretic forces become the dominant forces when the gravitational force is diminished, and they are strongly dependent on the momentum transfer between gas molecules and the surface. The momentum transfer, in turn, depends on the gas and particle properties and the mean free path and kinetic energy of the gas molecules. The experimental program involves the particle levitation system shown. A micrometer size particle is held between two heat exchangers enclosed in a vacuum chamber by means of ac and dc electric fields. The ac field keeps the particle centered on the vertical axis of the chamber, and the dc field balances the gravitational force and the thermophoretic force. Some measurements of the thermophoretic force are presented in this paper.
Aquacultural Occupational Task Analysis.
ERIC Educational Resources Information Center
Dung, Elaine; Wakui, Lawrence S.
A study was conducted by the Office of the Chancellor for Community Colleges in Hawaii to assess the vocational skills required of workers in the aquaculture industry and to determine if these skills should be reflected in the community college curriculum. In addition to a review of relevant literature, the study involved field observations at 17…
ERIC Educational Resources Information Center
Barrett, Gerald V.; And Others
The report describes field studies involving nonsupervisory Naval maintenance and monitoring electronics personnel. The studies' results indicated that Naval retention was related to a number of individual and job attributes. Extended Naval tenure was associated with lower verbal and clerical aptitudes (Naval Test Battery); higher levels of…
ERIC Educational Resources Information Center
Schoen, Robert C.; Bray, Wendy; Wolfe, Christopher; Tazaz, Amanda M.; Nielsen, Lynne
2017-01-01
This study reports on the development and field study of K-TEEM, a web-based assessment instrument designed to measure mathematical knowledge for teaching (MKT) at the early elementary level. The development process involved alignment with early elementary curriculum standards, expert review of items and scoring criteria, cognitive interviews with…
A Field Observation on the Philosophy of Teaching Islamic and Arabic Studies
ERIC Educational Resources Information Center
Yaakub, Muhamadul Bakir Hj.
2009-01-01
Implementation of educational policy in designing curriculum details stands as a basis of conceptual educational practice. It is for sure involved time and space factors to become comprehensive and constructive, especially for teaching Islamic and Arabic studies within modern educational challenges where its uniqueness values in nature should be…
Formulating a New Model of College Choice and Persistence
ERIC Educational Resources Information Center
Southerland, J. Nathaniel
2006-01-01
The study of college choice and persistence enjoys a lengthy history. However, many of the prominent models upon which the majority of research in these fields is based arise from studies involving traditional 18- to 22-year-old residential students. This paper investigates the rapidly-evolving student population and formulates a new model for…
ERIC Educational Resources Information Center
Huang, Jun Song; Hung, Wei Loong
2018-01-01
Research management is an emerging field of study and its development is significant to the advancement of research enterprise. Developing the science of research management requires investigating social mechanisms involved in research management. Yet, studies on social mechanisms of research management is lacking in the literature. To address…
Effects of Cognitive Demand on Situational Interest and Running Task Performances
ERIC Educational Resources Information Center
Zhu, Xihe; Chen, Senlin
2017-01-01
This study examined the effect of cognitive demand on situational interest and performance using running tasks in physical education. Adolescents (N = 179) participated in a field study involving three different levels of cognitive demand. Running performances and situational interest were measured four times with a testing interval of seven days.…
A Mineral Processing Field Course
ERIC Educational Resources Information Center
Carmody, Maurice
2014-01-01
This article describes a field course in Cornwall looking at mineral processing with the focus on the chemistry involved. The course was split into two parts. The first looked at tin mining based around Penzance. This involved visiting mines, hunting for mineral samples, carrying out a stream survey and visiting the Camborne School of Mines…
38 CFR 21.4270 - Measurement of courses.
Code of Federal Regulations, 2010 CFR
2010-07-01
... section, if theory and class instruction constitute more than 50 percent of the required hours in a trade... shops and the time involved in field trips and group instruction may be included in computing the clock... programs and the time involved in field trips and individual and group instruction may be included in...
49 CFR 579.23 - Reporting requirements for manufacturers of 5,000 or more motorcycles annually.
Code of Federal Regulations, 2010 CFR
2010-10-01
... the report with a limit of five codes to be included. (c) Numbers of property damage claims, consumer... claims, consumer complaints, warranty claims, and field reports which involve the systems and components..., consumer complaints, warranty claims, or field reports, respectively, that involves the systems or...
Electrochemical formation of field emitters
Bernhardt, A.F.
1999-03-16
Electrochemical formation of field emitters, particularly useful in the fabrication of flat panel displays is disclosed. The fabrication involves field emitting points in a gated field emitter structure. Metal field emitters are formed by electroplating and the shape of the formed emitter is controlled by the potential imposed on the gate as well as on a separate counter electrode. This allows sharp emitters to be formed in a more inexpensive and manufacturable process than vacuum deposition processes used at present. The fabrication process involves etching of the gate metal and the dielectric layer down to the resistor layer, and then electroplating the etched area and forming an electroplated emitter point in the etched area. 12 figs.
On the Global Regularity for the 3D Magnetohydrodynamics Equations Involving Partial Components
NASA Astrophysics Data System (ADS)
Qian, Chenyin
2018-03-01
In this paper, we study the regularity criteria of the three-dimensional magnetohydrodynamics system in terms of some components of the velocity field and the magnetic field. With a decomposition of the four nonlinear terms of the system, this result gives an improvement of some corresponding previous works (Yamazaki in J Math Fluid Mech 16: 551-570, 2014; Jia and Zhou in Nonlinear Anal Real World Appl 13: 410-418, 2012).
NASA Astrophysics Data System (ADS)
Sanchez, M. J.; Santamarina, C.; Gai, X., Sr.; Teymouri, M., Sr.
2017-12-01
Stability and behavior of Hydrate Bearing Sediments (HBS) are characterized by the metastable character of the gas hydrate structure which strongly depends on thermo-hydro-chemo-mechanical (THCM) actions. Hydrate formation, dissociation and methane production from hydrate bearing sediments are coupled THCM processes that involve, amongst other, exothermic formation and endothermic dissociation of hydrate and ice phases, mixed fluid flow and large changes in fluid pressure. The analysis of available data from past field and laboratory experiments, and the optimization of future field production studies require a formal and robust numerical framework able to capture the very complex behavior of this type of soil. A comprehensive fully coupled THCM formulation has been developed and implemented into a finite element code to tackle problems involving gas hydrates sediments. Special attention is paid to the geomechanical behavior of HBS, and particularly to their response upon hydrate dissociation under loading. The numerical framework has been validated against recent experiments conducted under controlled conditions in the laboratory that challenge the proposed approach and highlight the complex interaction among THCM processes in HBS. The performance of the models in these case studies is highly satisfactory. Finally, the numerical code is applied to analyze the behavior of gas hydrate soils under field-scale conditions exploring different features of material behavior under possible reservoir conditions.
Koropatnick, Tanya; Goodson, Michael S.; Heath-Heckman, Elizabeth A. C.; McFall-Ngai, Margaret
2014-01-01
The symbiotic association between the Hawaiian bobtail squid Euprymna scolopes and the luminous marine bacterium Vibrio fischeri provides a unique opportunity to study epithelial morphogenesis. Shortly after hatching, the squid host harvests bacteria from the seawater using currents created by two elaborate fields of ciliated epithelia on the surface of the juvenile light organ. After light organ colonization, the symbiont population signals the gradual loss of the ciliated epithelia through apoptosis of the cells, which culminates in the complete regression of these tissues. Whereas aspects of this process have been studied at the morphological, biochemical and molecular levels, no in-depth analysis of the cellular events has been reported. Here we describe the cellular structure of the epithelial field and present evidence that the symbiosis-induced regression occurs in two steps. Using confocal microscopic analyses, we observed an initial epithelial remodeling, which serves to disable the function of the harvesting apparatus, followed by a protracted regression involving actin rearrangements and epithelial cell extrusion. We identified a metal-dependent gelatinolytic activity in the symbiont-induced morphogenic epithelial fields, suggesting the involvement of Zn-dependent matrix metalloproteinase(s) (MMP) in light organ morphogenesis. These data show that the bacterial symbionts not only induce apoptosis of the field, but also change the form, function and biochemistry of the cells as part of the morphogenic program. PMID:24648207
Koropatnick, Tanya; Goodson, Michael S; Heath-Heckman, Elizabeth A C; McFall-Ngai, Margaret
2014-02-01
The symbiotic association between the Hawaiian bobtail squid Euprymna scolopes and the luminous marine bacterium Vibrio fischeri provides a unique opportunity to study epithelial morphogenesis. Shortly after hatching, the squid host harvests bacteria from the seawater using currents created by two elaborate fields of ciliated epithelia on the surface of the juvenile light organ. After light organ colonization, the symbiont population signals the gradual loss of the ciliated epithelia through apoptosis of the cells, which culminates in the complete regression of these tissues. Whereas aspects of this process have been studied at the morphological, biochemical, and molecular levels, no in-depth analysis of the cellular events has been reported. Here we describe the cellular structure of the epithelial field and present evidence that the symbiosis-induced regression occurs in two steps. Using confocal microscopic analyses, we observed an initial epithelial remodeling, which serves to disable the function of the harvesting apparatus, followed by a protracted regression involving actin rearrangements and epithelial cell extrusion. We identified a metal-dependent gelatinolytic activity in the symbiont-induced morphogenic epithelial fields, suggesting the involvement of Zn-dependent matrix metalloproteinase(s) (MMP) in light organ morphogenesis. These data show that the bacterial symbionts not only induce apoptosis of the field, but also change the form, function, and biochemistry of the cells as part of the morphogenic program.
Black holes and stars in Horndeski theory
NASA Astrophysics Data System (ADS)
Babichev, Eugeny; Charmousis, Christos; Lehébel, Antoine
2016-08-01
We review black hole and star solutions for Horndeski theory. For non-shift symmetric theories, black holes involve a Kaluza-Klein reduction of higher dimensional Lovelock solutions. On the other hand, for shift symmetric theories of Horndeski and beyond Horndeski, black holes involve two classes of solutions: those that include, at the level of the action, a linear coupling to the Gauss-Bonnet term and those that involve time dependence in the galileon field. We analyze the latter class in detail for a specific subclass of Horndeski theory, discussing the general solution of a static and spherically symmetric spacetime. We then discuss stability issues, slowly rotating solutions as well as black holes coupled to matter. The latter case involves a conformally coupled scalar field as well as an electromagnetic field and the (primary) hair black holes thus obtained. We review and discuss the recent results on neutron stars in Horndeski theories.
Reserve Growth of Alberta Oil Pools
Verma, Mahendra K.; Cook, Troy
2008-01-01
This Open-File Report is based on a presentation delivered at the Fourth U.S. Geological Survey Workshop on Reserve Growth on March 10-11, 2008. It summarizes the results of a study of reserve growth of oil pools in Alberta Province, Canada. The study is part of a larger effort involving similar studies of fields in other important petroleum provinces around the world, with the overall objective of gaining a better understanding of reserve growth in fields with different geologic/reservoir parameters and different operating environments. The goals of the study were to: 1. Evaluate historical oil reserve data and assess reserve growth. 2. Develop reserve growth models/functions to help forecast hydrocarbon volumes. 3. Study reserve growth sensitivity to various parameters ? for example, pool size, porosity, oil gravity, and lithology. 4. Compare reserve growth in oil pools/fields of Alberta provinces with those from other large petroleum provinces.
Influence of a magnetic field during directional solidification of MAR-M 246 + Hf superalloy
NASA Technical Reports Server (NTRS)
Andrews, J. Barry; Alter, Wendy; Schmidt, Dianne
1991-01-01
An area that has been almost totally overlooked in the optimization of properties in directionally solidified superalloys is the control of microstructural features through the application of a magnetic field during solidification. The influence of a magnetic field on the microstructural features of a nickel-base superalloys is investigated. Studies were performed on the dendritic MAR-M 246+Hf alloy, which was solidified under both a 5 K gauss magnetic field and under no-applied-field conditions. The possible influences of the magnetic field on the solidification process were observed by studying variations in microstructural features including volume fraction, surface area, number, and shape of the carbide particles. Stereological factors analyzed also included primary and secondary dendrite arm spacing and the volume fraction of the interdendritic eutectic constituent. Microprobe analysis was performed to determine the chemistry of the carbides, dendrites, and interdendritic constituents, and how it varied between field and no-field solidification samples. Experiments involving periodic application and removal of the magnetic field were also performed in order to permit a comparison with structural variations observed in a MAR-M 246+Hf alloy solidified during KC-135 high-g, low-g maneuvers.
Su, J; Zhu, S; Liu, Z; Zhao, Y; Song, C
2017-02-01
To compare the prognosis of elderly patients with early oesophageal carcinoma between radical elective nodal prophylactic irradiation and involved-field irradiation and to estimate the failure modes and adverse effects, then to provide the patients the safe and individual therapeutic regimens. The charts of 96 patients aged 65 and over with early stage oesophageal carcinoma receiving radical radiotherapy in our department were retrospectively analysed. Of all the patients, 49 received elective nodal prophylactic irradiation and the other 47 received involved-field irradiation. After completion of the whole treatment, we analysed short-term effects, tumour local control, overall survival of the patients, failure modes and adverse effects. The 1-, 3-, and 5-year local control rate in elective nodal irradiation and involved-field irradiation groups were 80.6%, 57.4%, 54.0% and 65.4%, 46.5%, 30.5% respectively, and the difference was statistically significant (χ 2 =4.478, P=0.03). The differences of overall survival and progression-free survival were not significant (P>0.05). The difference of 1-, 3-, and 5-years local regional failure rate was statistically significant between elective nodal prophylactic irradiation and involved-field irradiation groups, except for the overall failure and distant metastasis rates. The overall incidence of radiation-induced oesophagitis after elective nodal irradiation or involved-field irradiation was 79.6% and 59.6%, and the difference was statistically significant (χ 2 =4.559, P=0.03). The difference of radiation pneumonitis between elective nodal prophylactic irradiation and involved-field irradiation was not significant (12.2% vs 14.9%; χ 2 =0.144, P=0.7). For elderly patients with early stage oesophageal carcinoma receiving radical radiotherapy, although elective nodal prophylactic irradiation could increase the incidence of radiation-induced oesophagitis, patients could tolerate the treatment and benefit from local control. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.
NASA Technical Reports Server (NTRS)
Canacci, Victor A.; Braun, M. Jack
1994-01-01
The experimental approach presented here offers a nonintrusive, qualitative and quantitative evaluation of full field flow patterns applicable in various geometries in a variety of fluids. This Full Flow Field Tracking (FFFT) Particle Image Velocimetry (PIV) technique, by means of particle tracers illuminated by a laser light sheet, offers an alternative to Laser Doppler Velocimetry (LDV), and intrusive systems such as Hot Wire/Film Anemometry. The method makes obtainable the flow patterns, and allows quantitative determination of the velocities, accelerations, and mass flows of an entire flow field. The method uses a computer based digitizing system attached through an imaging board to a low luminosity camera. A customized optical train allows the system to become a long distance microscope (LDM), allowing magnifications of areas of interest ranging up to 100 times. Presented in addition to the method itself, are studies in which the flow patterns and velocities were observed and evaluated in three distinct geometries, with three different working fluids. The first study involved pressure and flow analysis of a brush seal in oil. The next application involved studying the velocity and flow patterns in a cowl lip cooling passage of an air breathing aircraft engine using water as the working fluid. Finally, the method was extended to a study in air to examine the flows in a staggered pin arrangement located on one side of a branched duct.
Stachenfeld, Nina S
2014-05-01
Changes in skin blood and sweating are the primary mechanisms for heat loss in humans. A hot, humid environment concomitant with dehydration limits the ability to increase skin blood flow for the purpose of transferring heat from the body core to skin surface and evaporate sweat to maintain core temperature within safe limits during exercise. Adequate hydration improves thermoregulation by maintaining blood volume to support skin blood flow and sweating. Humans rely on fluid intake to maintain total body water and blood volume, and have developed complex mechanisms to sense changes in the amount and composition of fluid in the body. This paper addresses the interrelationship of research in the laboratory and the field to assess hydration status involved in body water and temperature regulation during exercise. In the controlled setting of a research laboratory, investigators are able to investigate the contributions of volume and tonicity of fluid in the plasma to body water and temperature regulation during exercise and recovery. For example, laboratory studies have shown that tonicity in a rehydration beverage maintains the thirst mechanism (and stimulates drinking), and contributes to the ongoing stimulation of renal fluid retention hormones, ultimately leading to a more complete rehydration. Research in the field cannot control the environment precisely, but these studies provide a natural, 'real-life' setting to study fluid and temperature regulation during exercise. The conditions encountered in the field are closest to the environment during competition, and data collected in the field can have an immediate impact on performance and safety during exercise. There is an important synergy between these two methods of collecting data that support performance and protect athletes from harm during training and improve performance during competition.
Developments in the field of allergy in 2010 through the eyes of Clinical and Experimental Allergy.
Katelaris, C H; Linneberg, A; Magnan, A; Thomas, W R; Wardlaw, A J; Wark, P
2011-12-01
In 2010 over 200 articles were published in Clinical and Experimental Allergy including editorials, reviews, opinion articles, letters, book reviews and of course at the heart of the journal, papers containing original data which have moved the field of allergy forward on a number of fronts. For the third year running the editors felt it would be of value to summarize the key messages contained in these papers as a snapshot of where the cutting edge of research into allergic disease is leading. We have broadly followed the sections of the journal, although this year the mechanistic articles are grouped together and the studies involving experimental models of disease are discussed throughout the paper. In the field of asthma and rhinitis phenotypes and biomarkers continue to a major pre-occupation of our authors. There is continued interest in mechanisms of inflammation and disordered lung function with the mouse model of asthma continuing to offer new insights. There is also a steady flow of papers investigating new therapies, including those derived from plants and herbs, although many are mechanistic with too few high quality clinical trials. The mechanisms involved in allergic disease are well covered with many strong papers using clinical material to ask relevant questions. Pro-pre and snybiotics continue to be of major interest to our authors and this remains a controversial and complicated field. The discipline of epidemiology has retained its interest in risk factors for the development of allergic disease with a view to refining and debating the reasons for the allergy epidemic. There is continued interest in the relationship between helminthic disease and allergy with a new twist in 2010 involving studies using infection with helminths as a potential treatment. The genetics of allergic disease continues to be very productive, although the field has moved on from only investigating single nucleotide polymorphisms of candidate genes to Genome Wide Association Studies and an increasing and welcome emphasis on gene-environment interactions. In the field of clinical allergy there is steady flow of papers describing patterns of drug allergy with renewed interest in reactions to contrast media, but food allergy is the major area of interest in this section of the journal. Lastly in the field of allergens there is a growing interest in the role of component resolved diagnosis in improving the diagnosis and management of allergic disease. Another excellent year, full of fascinating and high quality work, which the journal has been proud to bring to the allergy community. © 2011 Blackwell Publishing Ltd.
Polychronidou, Eleftheria; Vlachakis, Dimitrios; Vlamos, Panayiotis; Baumann, Marc; Kossida, Sophia
2015-01-01
Notch signaling is a master controller of the neural stem cell and neural development maintaining a significant role in the normal brain function. Notch genes are involved in embryogenesis, nervous system, and cardiovascular and endocrine function. On the other side, there are studies representing the involvement of Notch mutations in sporadic Alzheimer disease, other neurodegenerative diseases such as Down syndrome, Pick's and Prion's disease, and CADASIL. This manuscript attempts to present a holistic view of the positive or negative contribution of Notch signaling in the adult brain, and at the same time to present and promote the promising research fields of study.
THE URBAN DISPERSION PROGRAM ( UDP ) NYC MSG05 EXPERIMENT
The multi-organizational Urban Dispersion Program (UDP) has been conducting tracer release experiments at various locations within the United States. In March 2005 the UDP conducted the first NYC based experiment called Madison Square Garden -05 (MSG05). The field study involved ...
Laboratory and field studies of photocatalytic NOx and O3 removal by coatings on concrete.
DOT National Transportation Integrated Search
2017-03-01
This project involved thorough testing of titanium dioxide (TiO2)-containing commercial photocatalytic coatings : applied to portland cement concrete for highway applications, focusing on the use of these coatings as an : abatement method for atmosph...
DOT National Transportation Integrated Search
2012-04-01
This study involved the identification and evaluation of laboratory conditioning methods and testing protocols considering heat oxidation, moisture, and load that more effectively simulate asphalt mixture aging in the field, and thereby help to prope...
Marine Biochemistry: A New Interdisciplinary Course for the Interim
ERIC Educational Resources Information Center
Goldberg, Arthur S.
1976-01-01
Discusses an undergraduate course which includes lectures, laboratory, and field trips and is designed for the interim winter semester. The course is interdisciplinary, involving a study of the biochemistry, pharmacology, and physiological significance of compounds from marine flora and fauna. (MLH)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tenforde, T.S.
1992-06-01
There is growing evidence that environmental electric and magnetic fields in the extremely-low-frequency (ELF) band below 300 Hz can influence biological functions by mechanisms that are only poorly understood at the present time. The primary objectives of this paper are to review the physical properties of ELF fields, their interactions with living systems at the tissue, cellular, and subcellular levels, and the key role of cell membranes ;in the transduction of signals from imposed ELF fields. Topics of discussion include signal-to-noise ratios for single cells and cell aggregates, resonance phenomena involving a combination of static and ELF magnetic fields, andmore » the possible influence of ELF fields on molecular signaling pathways that involve membrane receptors and cytoplasmic second messengers.« less
All-optical signatures of strong-field QED in the vacuum emission picture
NASA Astrophysics Data System (ADS)
Gies, Holger; Karbstein, Felix; Kohlfürst, Christian
2018-02-01
We study all-optical signatures of the effective nonlinear couplings among electromagnetic fields in the quantum vacuum, using the collision of two focused high-intensity laser pulses as an example. The experimental signatures of quantum vacuum nonlinearities are encoded in signal photons, whose kinematic and polarization properties differ from the photons constituting the macroscopic laser fields. We implement an efficient numerical algorithm allowing for the theoretical investigation of such signatures in realistic field configurations accessible in experiment. This algorithm is based on a vacuum emission scheme and can readily be adapted to the collision of more laser beams or further involved field configurations. We solve the case of two colliding pulses in full 3 +1 -dimensional spacetime and identify experimental geometries and parameter regimes with improved signal-to-noise ratios.
Study of ICRF wave propagation and plasma coupling efficiency in a linear magnetic mirror device
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peng, S.Y.
1991-07-01
Ion Cyclotron Range of Frequency (ICRF) wave propagation in an inhomogeneous axial magnetic field in a cylindrical plasma-vacuum system has historically been inadequately modelled. Previous works either sacrifice the cylindrical geometry in favor of a simpler slab geometry, concentrate on the resonance region, use a single mode to represent the entire field structure, or examine only radial propagation. This thesis performs both analytical and computational studies to model the ICRF wave-plasma coupling and propagation problem. Experimental analysis is also conducted to compare experimental results with theoretical predictions. Both theoretical as well as experimental analysis are undertaken as part of themore » thesis. The theoretical studies simulate the propagation of ICRF waves in an axially inhomogeneous magnetic field and in cylindrical geometry. Two theoretical analysis are undertaken - an analytical study and a computational study. The analytical study treats the inhomogeneous magnetic field by transforming the (r,z) coordinate into another coordinate system ({rho},{xi}) that allows the solution of the fields with much simpler boundaries. The plasma fields are then Fourier transformed into two coupled convolution-integral equations which are then differenced and solved for both the perpendicular mode number {alpha} as well as the complete EM fields. The computational study involves a multiple eigenmode computational analysis of the fields that exist within the plasma-vacuum system. The inhomogeneous axial field is treated by dividing the geometry into a series of transverse axial slices and using a constant dielectric tensor in each individual slice. The slices are then connected by longitudinal boundary conditions.« less
Job Involvement and Organizational Commitment of Employees of Prehospital Emergency Medical System.
Rahati, Alireza; Sotudeh-Arani, Hossein; Adib-Hajbaghery, Mohsen; Rostami, Majid
2015-12-01
Several studies are available on organizational commitment of employees in different organizations. However, the organizational commitment and job involvement of the employees in the prehospital emergency medical system (PEMS) of Iran have largely been ignored. This study aimed to investigate the organizational commitment and job involvement of the employees of PEMS and the relationship between these two issues. This cross-sectional study was conducted on 160 employees of Kashan PEMS who were selected through a census method in 2014. A 3-part instrument was used in this study, including a demographic questionnaire, the Allen and Miller's organizational commitment inventory, and the Lodahl and Kejner's job involvement inventory. We used descriptive statistics, Spearman correlation coefficient, Kruskal-Wallis, Friedman, analysis of variance, and Tukey post hoc tests to analyze the data. The mean job involvement and organizational commitment scores were 61.78 ± 10.69 and 73.89 ± 13.58, respectively. The mean scores of job involvement and organizational commitment were significantly different in subjects with different work experiences (P = 0.043 and P = 0.012, respectively). However, no significant differences were observed between the mean scores of organizational commitment and job involvement in subjects with different fields of study, different levels of interest in the profession, and various educational levels. A direct significant correlation was found between the total scores of organizational commitment and job involvement of workers in Kashan PEMS (r = 0.910, P < 0.001). This study showed that the employees in the Kashan PEMS obtained half of the score of organizational commitment and about two-thirds of the job involvement score. Therefore, the higher level managers of the emergency medical system are advised to implement some strategies to increase the employees' job involvement and organizational commitment.
Reionization and CMB non-Gaussianity
NASA Astrophysics Data System (ADS)
Munshi, D.; Corasaniti, P. S.; Coles, P.; Heavens, A.; Pandolfi, S.
2014-08-01
We show how cross-correlating a high-redshift external tracer field, such as the 21-cm neutral hydrogen distribution and product maps involving cosmic microwave background (CMB) temperature and polarization fields, that probe mixed bispectrum involving these fields, can help to determine the reionization history of the Universe, beyond what can be achieved from cross-spectrum analysis. Taking clues from recent studies for the detection of primordial non-Gaussianity, we develop a set of estimators that can study reionization using a power spectrum associated with the bispectrum (or skew-spectrum). We use the matched filtering inherent in this method to investigate different reionization histories. We check to what extent they can be used to rule out various models of reionization and study cross-contamination from different sources such as the lensing of the CMB. The estimators can be fine-tuned to optimize study of a specific reionization history. We consider three different types of tracers in our study, namely: proto-galaxies; 21-cm maps of neutral hydrogen; and quasars. We also consider four alternative models of reionization. We find that the cumulative signal-to-noise ratio (S/N) for detection at ℓmax = 2000 can reach O(70) for cosmic variance limited all-sky experiments. Combining 100 GHz, 143 GHz and 217 GHz channels of the Planck experiment, we find that the S/N lies in the range O(5)-O(35). The S/N depends on the specific choice of a tracer field, and multiple tracers can be effectively used to map out the entire reionization history with reasonable S/N. Contamination from weak lensing is investigated and found to be negligible, and the effects of Thomson scattering from patchy reionization are also considered.
ERIC Educational Resources Information Center
Lansiquot, Reneta D.
2013-01-01
Involving two or more academic subjects, interdisciplinary studies aim to blend together broad perspectives, knowledge, skills, and epistemology in an educational setting. By focusing on topics or questions too broad for a single discipline to cover, these studies strive to draw connections between seemingly different fields. Cases on…
ERIC Educational Resources Information Center
Jorgensen Zebenbergen, Robyn
2011-01-01
This paper presents a case study of contemporary retail industry and the ways in which young workers participate in that field. Public perceptions of low numeracy among young people provided the catalyst for the study. Drawing on a mixed-method approach involving survey, case studies, stimulated recall, observations, and interviews, it was found…
Influence of magnetic field on evaporation of a ferrofluid droplet
NASA Astrophysics Data System (ADS)
Jadav, Mudra; Patel, R. J.; Mehta, R. V.
2017-10-01
This paper reports the influence of the static magnetic field on the evaporation of a ferrofluid droplet placed on a plane glass substrate. A water based ferrofluid drop is allowed to dry under ambient conditions. Like all other fluids, this fluid also exhibits well-known coffee ring patterns under zero field conditions. This pattern is shown to be modulated by applying the static magnetic field. When the field is applied in a direction perpendicular to the plane of the substrate, the thickness of the ring decreases with an increase in the field, and under a critical value of the field, the coffee-ring effect is suppressed. For the parallel field configuration, linear chains parallel to the plane of the substrate are observed. The effect of the field on the evaporation rate and temporal variation of the contact angle is also studied. The results are analyzed in light of available models. These findings may be useful in applications like ink-jet printing, lithography, and painting and display devices involving ferrofluids.
[Development of the unexpected reality scale for childcare training].
Matsuda, Yuko; Shitara, Saeko; Hamada, Shoko
2016-10-01
This study aimed to develop a scale for unexpected reality for childcare training (Study 1) and examine the change and influence it exerts on the efficacy of preschool teachers (Study 2). In Study 1, the sample consisted of 571 university and junior college students enrolled in a childcare course. After exploratory factor analysis, four factors were extracted: “actual feelings for childcare as a field of study,” “difficulties faced during involvement with children,” “negative aspects of the childcare worker,” and “severity of work.” The study’s scale was shown to be internally consistent and valid. In Study 2, the sample consisted of 122 junior college students enrolled in a childcare course. The results showed that the high-scoring groups of each unexpected reality subscales experienced less unexpected reality in the subsequent training session. Moreover, the results of multiple regression showed that preschool teacher efficacy was predicted positively by “actual feelings for childcare as a field of study” and negatively by “difficulties faced during involvement with children.” Thus, we suggest that for effective pre- and post-guidance of childcare training, unexpected realities should be considered.
ERIC Educational Resources Information Center
Spais, George S.
2005-01-01
The major objective of this study is to identify a methodology that will help educators in marketing to efficiently manage the design, impact, and cost of case studies. It is my intention is to examine the impact of case study characteristics in relation to the degree of learner involvement in the learning process. The author proposes that…
Moneuse, M
2001-01-01
In France, RF and microwave techniques are now mature. They are commercialized by industries having now reliable references in different fields of manufacturing industry. The present situation is the result of many studies and collaborations where universities and public technical centers were strongly involved during the last three decades. During this period, the "Club Rayonnements" sponsored by EDF has been a real "melting pot" for people coming from university, industry and technical centers.
ERIC Educational Resources Information Center
Ashline, Melissa
This review of the professional and programmatic literature in the field of developmental disabilities focuses on ways in which individuals with developmental disabilities and their families are becoming increasingly involved in program evaluation and quality assurance efforts. Three major movements are having an impact on this activity: state and…
Electric and magnetic fields and tumor progression. Final report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keng, P.C.; Grota, L.J.; Michaelson, S.
This laboratory study has rigorously investigated two previously reported biological effects of 60-Hz electric and magnetic fields. The first effect involves nighttime suppression of melatonin synthesis in the pineal glands of rats exposed to high electric fields. The second concerns the increase in colony forming ability of human colon cancer cells exposed to 1.4-G magnetic fields. Neither effect was detected in the present study. A series of published laboratory studies on rats reported that 60-Hz electric fields at various field levels up to 130 kV/m suppress the nighttime synthesis of melatonin, a hormone produced by the pineal gland. Since melatoninmore » is known to modulate the immune system and may inhibit cancer cell activity, changes in physiological levels of melatonin may have significant health consequences. In the repeat experiments, field exposure did not alter nighttime levels of melatonin or enzyme activities in the pineal gland. A small but statistically significant reduction of about 20% in serum melatonin was seen in exposed animals. Pineal melatonin was also unaffected by the presence of red light as a cofactor with field exposure or by time-shifting the daily field exposure period. Another study reported that 60-Hz magnetic fields can affect the colony forming ability of human cancer cells after exposure in a culture medium. In the repeat experiments, field exposure did not alter the colony forming ability of human Colo 205 cells in two different cell concentrations at plating or in two different incubation conditions. Field exposure also did not affect cell cycling in any of the four cell lines tested.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Jing; Hu, Jiawei; Yu, Hongwei, E-mail: hwyu@hunnu.edu.cn
We study the spontaneous excitation of a circularly accelerated atom coupled with vacuum Dirac field fluctuations by separately calculating the contribution to the excitation rate of vacuum fluctuations and a cross term which involves both vacuum fluctuations and radiation reaction, and demonstrate that although the spontaneous excitation for the atom in its ground state would occur in vacuum, such atoms in circular motion do not perceive a pure thermal radiation as their counterparts in linear acceleration do since the transition rates of the atom do not contain the Planckian factor characterizing a thermal bath. We also find that the contributionmore » of the cross term that plays the same role as that of radiation reaction in the scalar and electromagnetic fields cases differs for atoms in circular motion from those in linear acceleration. This suggests that the conclusion drawn for atoms coupled with the scalar and electromagnetic fields that the contribution of radiation reaction to the mean rate of change of atomic energy does not vary as the trajectory of the atom changes from linear acceleration to circular motion is not a general trait that applies to the Dirac field where the role of radiation reaction is played by the cross term. - Highlights: • Spontaneous excitation of a circularly accelerated atom is studied. • The atom interacts with the Dirac field through nonlinear coupling. • A cross term involving vacuum fluctuations and radiation reaction contributes. • The atom in circular motion does not perceive pure thermal radiation. • The contribution of the cross term changes as the atomic trajectory varies.« less
Liu, Ziyuan; Wang, Hongli; Fan, Dongsheng; Wang, Wei
2018-02-01
Recent studies revealing genetic connection of primary open angle glaucoma (POAG) and amyotrophic lateral sclerosis (ALS) have received particular attention. Exploring the evidence for common pathogenesis of these two progressive neurological disorders may assist in understanding the mechanism and searching for new treatment. Retinal nerve fiber layer (RNFL) defect and corresponding visual field (VF) impairment are well known neuropathy signs in glaucoma. In our study, thickness of certain retinal layer in ALS patients was analyzed to detect ganglion cell's soma and axon, and for first time visual field was examined for ALS. The correlation of retinal involvement and ALS progression were also investigated. The results were compared with those of POAG. The study may provide new knowledge for these two neurodegenerative diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sports Involvement and Academic Achievement: A Study of Malaysian University Athletes
ERIC Educational Resources Information Center
Chuan, Chun Cheng; Yusof, Aminuddin; Shah, Parilah Mohd
2013-01-01
Factors that influence the academic achievement of Malaysian university athletes were investigated using 156 field hockey players from several universities. The relationship between team subculture, parental influence, the learning environment, support systems, financial aid, training factors, academic assistance, socialization, and stress level…
COMPARISON OF MEASUREMENTS OF AMBIENT PARTICLE NITRATE WITH SEMI-CONTINUOUS INSTRUMENTS
Comparisons between two different semi-continuous monitors of ambient level particulate nitrate are interpreted for both field and laboratory studies. One instrument involves thermal desorption of particulate nitrate to form a combination of NO and NO2 gases which are detected ...
COMPARISON OF MEASUREMENT OF AMBIENT PARTICLE NITRATE WITH SEMI-CONTINUOPUS INSTRUMENTS
Comparisons between two different semi-continuos monitors of ambient level particulate nitrate are interpreted for both field and laboratory studies. One instrument involves flash vaporization of impacted particulate nitrate to form a combination of NO and NO2 gases which are de...
ERIC Educational Resources Information Center
Ennis, Lisa A.
2007-01-01
The dynamic and rapidly expanding field of neuroscience traditionally has involved the study of the nervous system from a biological/medical standpoint. In recent years, however, the science has become multidisciplinary, attracting researchers from computer science, psychology, sociology, philosophy, and even the humanities. For public and college…
Synthesizing Regression Results: A Factored Likelihood Method
ERIC Educational Resources Information Center
Wu, Meng-Jia; Becker, Betsy Jane
2013-01-01
Regression methods are widely used by researchers in many fields, yet methods for synthesizing regression results are scarce. This study proposes using a factored likelihood method, originally developed to handle missing data, to appropriately synthesize regression models involving different predictors. This method uses the correlations reported…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanson, G.N.; Meyers, W.J.
1992-07-01
This grant supports research on the origins and geochemical aspects of regional dolomites. Eight graduate students are involved in research on dolomite allowing a diverse range of studies. This report outlines their work in the field. (JL)
ERIC Educational Resources Information Center
Lyons, Thomas T.
1972-01-01
Description of three years' experience with an interdisciplinary, field experience course, Man & Society," instituted at the Phillips Academy in 1970. It involved comparative societal study with a nine-week working and living experience in Boston and Mexico, a combination of student, teacher, and joint leadership, group discussion, and joint…
Social Identity and Achievement Gaps: Evidence from an Affirmation Intervention
ERIC Educational Resources Information Center
Dee, Thomas S.
2015-01-01
One provocative explanation for the continued persistence of minority achievement gaps involves the performance-dampening anxiety thought to be experienced by minority students in highly evaluative settings (i.e., "stereotype threat"). Recent field-experimental studies suggest that modest, low-cost "buffering" interventions…
ERIC Educational Resources Information Center
Edwards, Lesley
Designed for community students interested in learning about psychology as a field of study, this module offers group and individual activities to involve the beginning student in research, experimentation and discussion. Unit 1, "What Is Psychology?," includes the use of animals in psychology, ethics, the history of psychology, an…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Smith, E.J.; Tsurutani, B.T.
1976-05-01
Lion roars, which are intense packets of electromagnetic waves characteristically found in the magneosheath, have been studied. On the basis of these observations, several possible wave generation mechanisms are examined. Landau resonance is considered to be an unlikely source because this mechanism requires a substantial component of the wave electric field paralle to B, and the observation that the waves propagate along the ambient field is contrary to this requirement. It is not obvious that electron cyclotron resonance is responsible, because the field magnitude decreases should cause T/sub parallel//T/sub perpendicular/ to increase, and this rise could lead to wave dampingmore » rather than wave growth. A model which is consistent with all the observations of this study is a proton cyclotron overstability involving 10-keV protons streaming through the magnetosheath. It appears possible that the streaming protons could produce both the waves and the field decreases and that all three would be coincident. (AIP)« less
Plasmon mass scale in two-dimensional classical nonequilibrium gauge theory
NASA Astrophysics Data System (ADS)
Lappi, T.; Peuron, J.
2018-02-01
We study the plasmon mass scale in classical gluodynamics in a two-dimensional configuration that mimics the boost-invariant initial color fields in a heavy-ion collision. We numerically measure the plasmon mass scale using three different methods: a hard thermal loop (HTL) expression involving the quasiparticle spectrum constructed from Coulomb gauge field correlators, an effective dispersion relation, and the measurement of oscillations between electric and magnetic energies after introducing a spatially uniform perturbation to the electric field. We find that the HTL expression and the uniform electric field measurement are in rough agreement. The effective dispersion relation agrees with other methods within a factor of 2. We also study the dependence on time and occupation number, observing similar trends as in three spatial dimensions, where a power-law dependence sets in after an occupation-number-dependent transient time. We observe a decrease of the plasmon mass squared as t-1 / 3 at late times.
A collection of flow visualization techniques used in the Aerodynamic Research Branch
NASA Technical Reports Server (NTRS)
1984-01-01
Theoretical and experimental research on unsteady aerodynamic flows is discussed. Complex flow fields that involve separations, vortex interactions, and transonic flow effects were investigated. Flow visualization techniques are used to obtain a global picture of the flow phenomena before detailed quantitative studies are undertaken. A wide variety of methods are used to visualize fluid flow and a sampling of these methods is presented. It is emphasized that the visualization technique is a thorough quantitative analysis and subsequent physical understanding of these flow fields.
Nonadiabatic Berry phase in nanocrystalline magnets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skomski, R.; Sellmyer, D. J.
2016-12-20
In this study, it is investigated how a Berry phase is created in polycrystalline nanomagnets and how the phase translates into an emergent magnetic field and into a topological Hall-effect contribution. The analysis starts directly from the spin of the conduction electrons and does not involve any adiabatic Hamiltonian. Completely random spin alignment in the nanocrystallites does not lead to a nonzero emergent field, but a modulation of the local magnetization does. As an explicit example, we consider a wire with a modulated cone angle.
Some new results on charged compact boson stars
Kumar, Sanjeev; Kulshreshtha, Usha; Kulshreshtha, Daya Shankar; ...
2017-07-21
In this work we present some new results obtained in a study of the phase diagram of charged compact boson stars in a theory involving a complex scalar field with a conical potential coupled to a U(1) gauge field and gravity. We here obtain new bifurcation points in this model. We present a detailed discussion of the various regions of the phase diagram with respect to the bifurcation points. The theory is seen to contain rich physics in a particular domain of the phase diagram.
Studies in Mindfulness: Widening the Field for All Involved in Pastoral Care
ERIC Educational Resources Information Center
Nixon, Graeme; McMurtry, David; Craig, Linda; Nevejan, Annick; Regan-Addis, Heather
2016-01-01
Since 2010, the University of Aberdeen, Scotland, UK, has offered an MSc in studies in mindfulness degree programme within its School of Education. The programme has attracted over 200 students from multiple professional contexts, providing the authors with the opportunity to gather and analyse demographic data, as well as data regarding student…
Communication Variables Associated with Hearing-Impaired/Vision-Impaired Persons--A Pilot-Study.
ERIC Educational Resources Information Center
Hicks, Wanda M.
1979-01-01
A study involving eight youths and adults with retinitis pigmentosa (and only 20 degree visual field and hearing loss of at least 20 decibels) determined variance in the ability to perceive and comprehend visual stimuli presented by way of the manual modality when modifications were made in configuration, movement speed, movement size, and…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pigg, Scott; Cautley, Dan; Francisco, Paul
2014-09-01
This report summarizes findings from a national field study of indoor air quality parameters in homes treated under the Weatherization Assistance Program (WAP). The study involved testing and monitoring in 514 single-family homes (including mobile homes) located in 35 states and served by 88 local weatherization agencies.
ERIC Educational Resources Information Center
Karns, Jack E.
In recent years the number of lawsuits brought by injured secondary school athletes alleging negligence on the part of coaches, school officials, and referees has risen dramatically. This study analyzes the legal liability implications for administrators and others involved in school sports in North Dakota. An introductory section describes…
ERIC Educational Resources Information Center
Cantor, Jeffrey A.
Business is recognizing that the associate degree is a necessity in high technology fields. Innovative practices link businesses with community colleges, allowing apprentices to gain basic job skills and a higher education. A research study explored three industries and their relationship with community colleges: automotive, construction, and…
ERIC Educational Resources Information Center
Schoen, Robert C.; Bray, Wendy; Wolfe, Christopher; Tazaz, Amanda M.; Nielsen, Lynne
2017-01-01
This study reports on the development and field study of K-TEEM, a web-based assessment instrument designed to measure mathematical knowledge for teaching (MKT) at the early elementary level. The development process involved alignment with early elementary curriculum standards, expert review of items and scoring criteria, cognitive interviews with…
NASA Technical Reports Server (NTRS)
Nishikawa, K.-I.; Hartmann, D. H.; Hardee, P.; Hededal, C.; Mizunno, Y.; Fishman, G. J.
2006-01-01
We performed numerical simulations of particle acceleration, magnetic field generation, and emission from shocks in order to understand the observed emission from relativistic jets and supernova remnants. The investigation involves the study of collisionless shocks, where the Weibel instability is responsible for particle acceleration as well as magnetic field generation. A 3-D relativistic particle-in-cell (RPIC) code has been used to investigate the shock processes in electron-positron plasmas. The evolution of theWeibe1 instability and its associated magnetic field generation and particle acceleration are studied with two different jet velocities (0 = 2,5 - slow, fast) corresponding to either outflows in supernova remnants or relativistic jets, such as those found in AGNs and microquasars. Slow jets have intrinsically different structures in both the generated magnetic fields and the accelerated particle spectrum. In particular, the jet head has a very weak magnetic field and the ambient electrons are strongly accelerated and dragged by the jet particles. The simulation results exhibit jitter radiation from inhomogeneous magnetic fields, generated by the Weibel instability, which has different spectral properties than standard synchrotron emission in a homogeneous magnetic field.
[Electromagnetic pollution (electrosmog)--potential hazards of our electromagnetic future].
Nowak, D; Radon, K
2004-02-26
The term electromagnetic environment encompasses the totality of all electric, magnetic and electromagnetic fields generated by natural and technical sources. A differentiation is made between low- and high-frequency electromagnetic fields. Typical sources of the former are domestic electricity Exposure to the latter is, for example, associated with the sue of mobile telephones. Studies on the health-related effects of electromagnetic fields are available in particular for the low-frequency range, based on an appropriate estimation of exposure. A number of these studies reveal an association between exposure to this type of electromagnetic fields and the occurrence of infantile leukemia in the highest exposure category. For high-frequency electromagnetic fields the number of epidemiological studies is limited. An increased risk of an accident occurring through the use of a cellular phone while driving has consistently been shown. Against the background of our limited knowledge about possible adverse effects of exposure to mobile phone transmitters, and the inability of the public to influence such exposure, transparency in the communication of the risks involved is of great importance.
Synchronization Design and Error Analysis of Near-Infrared Cameras in Surgical Navigation.
Cai, Ken; Yang, Rongqian; Chen, Huazhou; Huang, Yizhou; Wen, Xiaoyan; Huang, Wenhua; Ou, Shanxing
2016-01-01
The accuracy of optical tracking systems is important to scientists. With the improvements reported in this regard, such systems have been applied to an increasing number of operations. To enhance the accuracy of these systems further and to reduce the effect of synchronization and visual field errors, this study introduces a field-programmable gate array (FPGA)-based synchronization control method, a method for measuring synchronous errors, and an error distribution map in field of view. Synchronization control maximizes the parallel processing capability of FPGA, and synchronous error measurement can effectively detect the errors caused by synchronization in an optical tracking system. The distribution of positioning errors can be detected in field of view through the aforementioned error distribution map. Therefore, doctors can perform surgeries in areas with few positioning errors, and the accuracy of optical tracking systems is considerably improved. The system is analyzed and validated in this study through experiments that involve the proposed methods, which can eliminate positioning errors attributed to asynchronous cameras and different fields of view.
Watts, Sarah J; Jackman, Louisa; Howarth, Alan
2017-01-01
'Forced care' describes the provision of personal care to an individual who does not have the capacity to make a decision about that care and resists receiving that care. This study explored the views of clinical psychologists on supporting staff involved with forced care and considered the following question: Do clinical psychologists feel that they have a role in guiding decisions around forced care, and if so, what? Interview data were gathered from five clinical psychologists experienced in the field of Older Adult psychology in the UK. This study concludes that the environment in which psychologists work influences the psychologist's beliefs about whether psychologists should be involved with making recommendations about forced care, and how they should be involved.
Modeling nutrient in-stream processes at the watershed scale using Nutrient Spiralling metrics
NASA Astrophysics Data System (ADS)
Marcé, R.; Armengol, J.
2009-01-01
One of the fundamental problems of using large-scale biogeochemical models is the uncertainty involved in aggregating the components of fine-scale deterministic models in watershed applications, and in extrapolating the results of field-scale measurements to larger spatial scales. Although spatial or temporal lumping may reduce the problem, information obtained during fine-scale research may not apply to lumped categories. Thus, the use of knowledge gained through fine-scale studies to predict coarse-scale phenomena is not straightforward. In this study, we used the nutrient uptake metrics defined in the Nutrient Spiralling concept to formulate the equations governing total phosphorus in-stream fate in a watershed-scale biogeochemical model. The rationale of this approach relies on the fact that the working unit for the nutrient in-stream processes of most watershed-scale models is the reach, the same unit used in field research based on the Nutrient Spiralling concept. Automatic calibration of the model using data from the study watershed confirmed that the Nutrient Spiralling formulation is a convenient simplification of the biogeochemical transformations involved in total phosphorus in-stream fate. Following calibration, the model was used as a heuristic tool in two ways. First, we compared the Nutrient Spiralling metrics obtained during calibration with results obtained during field-based research in the study watershed. The simulated and measured metrics were similar, suggesting that information collected at the reach scale during research based on the Nutrient Spiralling concept can be directly incorporated into models, without the problems associated with upscaling results from fine-scale studies. Second, we used results from our model to examine some patterns observed in several reports on Nutrient Spiralling metrics measured in impaired streams. Although these two exercises involve circular reasoning and, consequently, cannot validate any hypothesis, this is a powerful example of how models can work as heuristic tools to compare hypotheses and stimulate research in ecology.
Particles trajectories in magnetic filaments
NASA Astrophysics Data System (ADS)
Bret, A.
2015-07-01
The motion of a particle in a spatially harmonic magnetic field is a basic problem involved, for example, in the mechanism of formation of a collisionless shock. In such settings, it is generally reasoned that particles entering a Weibel generated turbulence are trapped inside it, provided their Larmor radius in the peak field is smaller than the field coherence length. The goal of this work is to put this heuristic conclusion on firm ground by studying, both analytically and numerically, such motion. A toy model is analyzed, consisting of a relativistic particle entering a region of space occupied by a spatially harmonic field. The particle penetrates the magnetic structure in a direction aligned with the magnetic filaments. Although the conclusions are not trivial, the main result is confirmed.
Advani, R H; Hoppe, R T; Baer, D; Mason, J; Warnke, R; Allen, J; Daadi, S; Rosenberg, S A; Horning, S J
2013-04-01
To assess the efficacy of an abbreviated Stanford V regimen in patients with early-stage Hodgkin lymphoma (HL). PATIENTS AND METHODS PATIENTS: with untreated nonbulky stage I-IIA supradiaphragmatic HL were eligible for the G4 study. Stanford V chemotherapy was administered for 8 weeks followed by radiation therapy (RT) 30 Gy to involved fields (IF). Freedom from progression (FFP), disease-specific survival (DSS) and overall survival (OS) were estimated. All 87 enrolled patients completed the abbreviated regimen. At a median follow-up of 10 years, FFP, DSS and OS are 94%, 99% and 94%, respectively. Therapy was well tolerated with no treatment-related deaths. Mature results of the abbreviated Stanford V regimen in nonbulky early-stage HL are excellent and comparable to the results from other contemporary therapies.
Learning of goal-relevant and -irrelevant complex visual sequences in human V1.
Rosenthal, Clive R; Mallik, Indira; Caballero-Gaudes, Cesar; Sereno, Martin I; Soto, David
2018-06-12
Learning and memory are supported by a network involving the medial temporal lobe and linked neocortical regions. Emerging evidence indicates that primary visual cortex (i.e., V1) may contribute to recognition memory, but this has been tested only with a single visuospatial sequence as the target memorandum. The present study used functional magnetic resonance imaging to investigate whether human V1 can support the learning of multiple, concurrent complex visual sequences involving discontinous (second-order) associations. Two peripheral, goal-irrelevant but structured sequences of orientated gratings appeared simultaneously in fixed locations of the right and left visual fields alongside a central, goal-relevant sequence that was in the focus of spatial attention. Pseudorandom sequences were introduced at multiple intervals during the presentation of the three structured visual sequences to provide an online measure of sequence-specific knowledge at each retinotopic location. We found that a network involving the precuneus and V1 was involved in learning the structured sequence presented at central fixation, whereas right V1 was modulated by repeated exposure to the concurrent structured sequence presented in the left visual field. The same result was not found in left V1. These results indicate for the first time that human V1 can support the learning of multiple concurrent sequences involving complex discontinuous inter-item associations, even peripheral sequences that are goal-irrelevant. Copyright © 2018. Published by Elsevier Inc.
Cognitive chrono-ethnography lite.
Nakajima, Masato; Yamada, Kosuke C; Kitajima, Muneo
2012-01-01
Conducting field research facilitates understanding human daily activities. Cognitive Chrono-Ethnography (CCE) is a study methodology used to understand how people select actions in daily life by conducting ethnographical field research. CCE consists of measuring monitors' daily activities in a specified field and in-depth interviews using the recorded videos afterward. However, privacy issues may arise when conducting standard CCE with video recordings in a daily field. To resolve these issues, we developed a new study methodology, CCE Lite. To replace video recordings, we created pseudo-first-personview (PFPV) movies using a computer-graphic technique. The PFPV movies were used to remind the monitors of their activities. These movies replicated monitors' activities (e.g., locomotion and change in physical direction), with no human images and voices. We applied CCE Lite in a case study that involved female employees of hotels at a spa resort. In-depth interviews while showing the PFPV movies determined service schema of the employees (i.e., hospitality). Results indicated that using PFPV movies helped the employees to remember and reconstruct the situation of recorded activities.
High school students' representations and understandings of electric fields
NASA Astrophysics Data System (ADS)
Cao, Ying; Brizuela, Bárbara M.
2016-12-01
This study investigates the representations and understandings of electric fields expressed by Chinese high school students 15 to 16 years old who have not received high school level physics instruction. The physics education research literature has reported students' conceptions of electric fields postinstruction as indicated by students' performance on textbook-style questions. It has, however, inadequately captured student ideas expressed in other situations yet informative to educational research. In this study, we explore students' ideas of electric fields preinstruction as shown by students' representations produced in open-ended activities. 92 participant students completed a worksheet that involved drawing comic strips about electric charges as characters of a cartoon series. Three students who had spontaneously produced arrow diagrams were interviewed individually after class. We identified nine ideas related to electric fields that these three students spontaneously leveraged in the comic strip activity. In this paper, we describe in detail each idea and its situated context. As most research in the literature has understood students as having relatively fixed conceptions and mostly identified divergences in those conceptions from canonical targets, this study shows students' reasoning to be more variable in particular moments, and that variability includes common sense resources that can be productive for learning about electric fields.
Dattilio, Frank M; Edwards, David J A; Fishman, Daniel B
2010-12-01
This article addresses the long-standing divide between researchers and practitioners in the field of psychotherapy, regarding what really works in treatment and the extent to which interventions should be governed by outcomes generated in a "laboratory atmosphere." This alienation has its roots in a positivist paradigm, which is epistemologically incomplete because it fails to provide for context-based practical knowledge. In other fields of evaluation research, it has been superseded by a mixed methods paradigm, which embraces pragmatism and multiplicity. On the basis of this paradigm, we propose and illustrate new scientific standards for research on the evaluation of psychotherapeutic treatments. These include the requirement that projects should comprise several parallel studies that involve randomized controlled trials, qualitative examinations of the implementation of treatment programs, and systematic case studies. The uniqueness of this article is that it contributes a guideline for involving a set of complementary publications, including a review that offers an overall synthesis of the findings from different methodological approaches. (PsycINFO Database Record (c) 2010 APA, all rights reserved).
Metabolomics for Biomarker Discovery in Gastroenterological Cancer
Nishiumi, Shin; Suzuki, Makoto; Kobayashi, Takashi; Matsubara, Atsuki; Azuma, Takeshi; Yoshida, Masaru
2014-01-01
The study of the omics cascade, which involves comprehensive investigations based on genomics, transcriptomics, proteomics, metabolomics, etc., has developed rapidly and now plays an important role in life science research. Among such analyses, metabolome analysis, in which the concentrations of low molecular weight metabolites are comprehensively analyzed, has rapidly developed along with improvements in analytical technology, and hence, has been applied to a variety of research fields including the clinical, cell biology, and plant/food science fields. The metabolome represents the endpoint of the omics cascade and is also the closest point in the cascade to the phenotype. Moreover, it is affected by variations in not only the expression but also the enzymatic activity of several proteins. Therefore, metabolome analysis can be a useful approach for finding effective diagnostic markers and examining unknown pathological conditions. The number of studies involving metabolome analysis has recently been increasing year-on-year. Here, we describe the findings of studies that used metabolome analysis to attempt to discover biomarker candidates for gastroenterological cancer and discuss metabolome analysis-based disease diagnosis. PMID:25003943
Nishimura, Ritsuko; Yoshizaki, Kazuhito; Kato, Kimiko; Hatta, Takeshi
2009-01-01
The present study examined the role of visual presentation mode (unilateral vs. bilateral visual fields) on attentional modulation. We examined whether or not the presentation mode affects the compatibility effect, using a paradigm involving two task-relevant letter arrays. Sixteen participants identified a target letter among task-relevant letters while ignoring either a compatible or incompatible distracter letter that was presented to both hemispheres. Two letters arrays were presented to visual fields, either unilaterally or bilaterally. Results indicated that the compatibility effect was greater in bilateral than in unilateral visual field conditions. Findings support the assumption that the two hemispheres have separate attentional resources.
NASA Technical Reports Server (NTRS)
Dennison, B. K.
1976-01-01
The gravitational field is probed in a search for polarization dependence in the light bending. This involves searching for a splitting of a source image into orthogonal polarizations as the radiation passes through the solar gravitational field. This search was carried out using the techniques of very long and intermediate baseline interferometry, and by seeking a relative phase delay in orthogonal polarizations of microwaves passing through the solar gravitational field. In this last technique a change in the total polarization of the Helios 1 carrier wave was sought as the spacecraft passed behind the sun. No polarization splitting was detected.
Random walk study of electron motion in helium in crossed electromagnetic fields
NASA Technical Reports Server (NTRS)
Englert, G. W.
1972-01-01
Random walk theory, previously adapted to electron motion in the presence of an electric field, is extended to include a transverse magnetic field. In principle, the random walk approach avoids mathematical complexity and concomitant simplifying assumptions and permits determination of energy distributions and transport coefficients within the accuracy of available collisional cross section data. Application is made to a weakly ionized helium gas. Time of relaxation of electron energy distribution, determined by the random walk, is described by simple expressions based on energy exchange between the electron and an effective electric field. The restrictive effect of the magnetic field on electron motion, which increases the required number of collisions per walk to reach a terminal steady state condition, as well as the effect of the magnetic field on electron transport coefficients and mean energy can be quite adequately described by expressions involving only the Hall parameter.
Making history: Thomas Francis, Jr, MD, and the 1954 Salk Poliomyelitis Vaccine Field Trial.
Lambert, S M; Markel, H
2000-05-01
This article focuses on the poliomyelitis vaccine field trial directed by Thomas Francis,Jr, MD, of the University of Michigan Vaccine Evaluation Center and sponsored by the National Foundation for Infantile Paralysis (NFIP) or, as it was better known to the public, the March of Dimes. It was a landmark in the widescale testing of a vaccine and the ethical use of human subjects. Millions of American parents readily volunteered their healthy children to participate. A total of 150,000 volunteers, including schoolteachers, physicians, nurses, and health officers all endorsed the study and donated their time and effort to make it successful. Avoiding the use of marginalized groups, the field trial purposefully did not involve institutionalized children; instead, it was based in 15,000 public schools in 44 of the 48 states as clinic sites. A group of 650,000 children received some type of injection, either the vaccine or a placebo, and another 1.18 million served as controls. The field trial depended, most essentially, on both public support and the participation of millions of children who remained enrolled in a study that required a series of 3 injections and a 6-month evaluation period. Enlisting the huge number of participants presented practical examples of the difficulties in experimenting on human subjects. On April 26, 1954, Randy Kerr, a participant or "Polio Pioneer" as the children involved were called, received the first inoculation of the Salk poliomyelitis vaccine. The nationwide study "designed to test the safety and efficacy" of the Salk vaccine had officially begun.
ERIC Educational Resources Information Center
Parker, Mark A.
2011-01-01
Purpose: To provide an overview of the methodologies involved in the field of hair cell regeneration. First, the author provides a tutorial on the biotechnological foundations of this field to assist the reader in the comprehension and interpretation of the research involved in hair cell regeneration. Next, the author presents a review of stem…
Risk Assessment and Geography Teachers: A Survey
ERIC Educational Resources Information Center
Parry, Gareth; Clarke, Linda
2004-01-01
Recently the issue of health and safety procedures on field trips and school visits has come to the fore, as a result of a series of tragedies involving the deaths of pupils. A review of some of the recent court cases and inquests involving the victims of field trips was undertaken. This indicated that schools and teachers are failing to implement…
Guidelines for managing data and processes in bone and cartilage tissue engineering.
Viti, Federica; Scaglione, Silvia; Orro, Alessandro; Milanesi, Luciano
2014-01-01
In the last decades, a wide number of researchers/clinicians involved in tissue engineering field published several works about the possibility to induce a tissue regeneration guided by the use of biomaterials. To this aim, different scaffolds have been proposed, and their effectiveness tested through in vitro and/or in vivo experiments. In this context, integration and meta-analysis approaches are gaining importance for analyses and reuse of data as, for example, those concerning the bone and cartilage biomarkers, the biomolecular factors intervening in cell differentiation and growth, the morphology and the biomechanical performance of a neo-formed tissue, and, in general, the scaffolds' ability to promote tissue regeneration. Therefore standards and ontologies are becoming crucial, to provide a unifying knowledge framework for annotating data and supporting the semantic integration and the unambiguous interpretation of novel experimental results. In this paper a conceptual framework has been designed for bone/cartilage tissue engineering domain, by now completely lacking standardized methods. A set of guidelines has been provided, defining the minimum information set necessary for describing an experimental study involved in bone and cartilage regenerative medicine field. In addition, a Bone/Cartilage Tissue Engineering Ontology (BCTEO) has been developed to provide a representation of the domain's concepts, specifically oriented to cells, and chemical composition, morphology, physical characterization of biomaterials involved in bone/cartilage tissue engineering research. Considering that tissue engineering is a discipline that traverses different semantic fields and employs many data types, the proposed instruments represent a first attempt to standardize the domain knowledge and can provide a suitable means to integrate data across the field.
Future missions for observing Earth's changing gravity field: a closed-loop simulation tool
NASA Astrophysics Data System (ADS)
Visser, P. N.
2008-12-01
The GRACE mission has successfully demonstrated the observation from space of the changing Earth's gravity field at length and time scales of typically 1000 km and 10-30 days, respectively. Many scientific communities strongly advertise the need for continuity of observing Earth's gravity field from space. Moreover, a strong interest is being expressed to have gravity missions that allow a more detailed sampling of the Earth's gravity field both in time and in space. Designing a gravity field mission for the future is a complicated process that involves making many trade-offs, such as trade-offs between spatial, temporal resolution and financial budget. Moreover, it involves the optimization of many parameters, such as orbital parameters (height, inclination), distinction between which gravity sources to observe or correct for (for example are gravity changes due to ocean currents a nuisance or a signal to be retrieved?), observation techniques (low-low satellite-to-satellite tracking, satellite gravity gradiometry, accelerometers), and satellite control systems (drag-free?). A comprehensive tool has been developed and implemented that allows the closed-loop simulation of gravity field retrievals for different satellite mission scenarios. This paper provides a description of this tool. Moreover, its capabilities are demonstrated by a few case studies. Acknowledgments. The research that is being done with the closed-loop simulation tool is partially funded by the European Space Agency (ESA). An important component of the tool is the GEODYN software, kindly provided by NASA Goddard Space Flight Center in Greenbelt, Maryland.
Stam, Rianne
2014-01-01
Some of the strongest electromagnetic fields (EMF) are found in the workplace. A European Directive sets limits to workers’ exposure to EMF. This review summarizes its origin and contents and compares magnetic field exposure levels in high-risk workplaces with the limits set in the revised Directive. Pubmed, Scopus, grey literature databases, and websites of organizations involved in occupational exposure measurements were searched. The focus was on EMF with frequencies up to 10 MHz, which can cause stimulation of the nervous system. Selected studies had to provide individual maximum exposure levels at the workplace, either in terms of the external magnetic field strength or flux density or as induced electric field strength or current density. Indicative action levels and the corresponding exposure limit values for magnetic fields in the revised European Directive will be higher than those in the previous version. Nevertheless, magnetic flux densities in excess of the action levels for peripheral nerve stimulation are reported for workers involved in welding, induction heating, transcranial magnetic stimulation, and magnetic resonance imaging (MRI). The corresponding health effects exposure limit values for the electric fields in the worker’s body can be exceeded for welding and MRI, but calculations for induction heating and transcranial magnetic stimulation are lacking. Since the revised European Directive conditionally exempts MRI-related activities from the exposure limits, measures to reduce exposure may be necessary for welding, induction heating, and transcranial nerve stimulation. Since such measures can be complicated, there is a clear need for exposure databases for different workplace scenarios with significant EMF exposure and guidance on good practices. PMID:24557933
Lower crustal mush generation and evolution
NASA Astrophysics Data System (ADS)
Karakas, Ozge; Bachmann, Olivier; Dufek, Josef; Wright, Heather; Mangan, Margaret
2016-04-01
Recent seismic, field, and petrologic studies on several active and fossil volcanic settings provide important constraints on the time, volume, and melt fraction of their lower crustal magma bodies. However, these studies provide an incomplete picture of the time and length scales involved during their thermal and compositional evolution. What has been lacking is a thermal model that explains the temporal evolution and state of the lower crustal magma bodies during their growth. Here we use a two-dimensional thermal model and quantify the time and length scales involved in the long-term thermal and compositional evolution of the lower crustal mush regions underlying the Salton Sea Geothermal Field (USA), Mt St Helens (USA), and the Ivrea-Verbano Zone (North Italy). Although a number of seismic, tectonic, petrologic, and field studies explained the tectonic and magmatic evolution of these regions, controversy remains on their lower crustal heat sources, melt fraction, and origin of erupted magmas. Our thermal modeling results suggest that given a geologically reasonable range of basalt fluxes (~10^-3 to 10^-4 km3/yr), a long-lived (>105 yr) crystalline mush is formed in the lower crust. The state of the lower crustal mush is strongly influenced by the magma flux, crustal thickness, and water content of intruded basalt, giving an average melt fraction of <0.2 in thin crust with dry injections (Salton Sea Geothermal Field) and up to 0.4-0.5 in thicker crust with wet injections (Mt St Helens and Ivrea Zone). The melt in the lower crustal mush is mainly evolving through fractional crystallization of basalt with minor crustal assimilation in all regions, in agreement with isotopic studies. Quantification of the lower crustal mush regions is key to understanding the mass and heat balance in the crust, evolution of magma plumbing systems, and geothermal energy exploration.
ERIC Educational Resources Information Center
Laurillard, D. M.
This study of the feasibility of using existing videocassettes for interactive video included field tests with Open University summer school students. The aims of the study were to discover whether video material originally made for broadcast could be used in an interactive program which involves breaking up the intended flow of the program;…
ERIC Educational Resources Information Center
Fox-Parrish, Lynne; Jurin, Richard R.
2008-01-01
The authors used a case-study methodology to explore the perceptions of 30 9th-grade biology students relative to black-tailed prairie dogs. The case study, which involved classroom- and field-based experiences that focused on black-tailed prairie dogs, revealed 3 major themes: apathy, egocentrism, and naive conceptions. The authors had hoped that…
Brain Dynamics Sustaining Rapid Rule Extraction from Speech
ERIC Educational Resources Information Center
de Diego-Balaguer, Ruth; Fuentemilla, Lluis; Rodriguez-Fornells, Antoni
2011-01-01
Language acquisition is a complex process that requires the synergic involvement of different cognitive functions, which include extracting and storing the words of the language and their embedded rules for progressive acquisition of grammatical information. As has been shown in other fields that study learning processes, synchronization…
We compared classification schemes based on watershed storage (wetland + lake area/watershed area) and forest fragmentation with a geographically-based classification scheme for two case studies involving 1) Lake Superior tributaries and 2) watersheds of riverine coastal wetlands...
36 CFR 800.4 - Identification of historic properties.
Code of Federal Regulations, 2010 CFR
2010-07-01
... the steps necessary to identify historic properties within the area of potential effects. (1) Level of..., research and studies, the magnitude and nature of the undertaking and the degree of Federal involvement... research, consultation and an appropriate level of field investigation, taking into account the number of...
A Conceptual Structure of Visual Metaphor
ERIC Educational Resources Information Center
Serig, Daniel
2006-01-01
The study of metaphor involves numerous fields in recent history from cognitive neuroscience to linguistics. Visual metaphor research occupies an underrepresented area of inquiry. With the development of the cognitive sciences, a cognitive view of metaphoric thinking is emerging. This calls for a reconsideration of visual metaphor in the…
We compared classification schemes based on watershed storage (wetland + lake area/watershed area) and forest fragmentation with a geographically-based classification scheme for two case studies involving 1)Lake Superior tributaries and 2) watersheds of riverine coastal wetlands ...
Lorentz and diffeomorphism violations in linearized gravity
NASA Astrophysics Data System (ADS)
Kostelecký, V. Alan; Mewes, Matthew
2018-04-01
Lorentz and diffeomorphism violations are studied in linearized gravity using effective field theory. A classification of all gauge-invariant and gauge-violating terms is given. The exact covariant dispersion relation for gravitational modes involving operators of arbitrary mass dimension is constructed, and various special limits are discussed.
Advances in high-throughput next-generation sequencing (NGS) technology for direct sequencing of environmental DNA (i.e. shotgun metagenomics) is transforming the field of microbiology. NGS technologies are now regularly being applied in comparative metagenomic studies, which pr...
Enhancing Community Service Learning via Practical Learning Communities
ERIC Educational Resources Information Center
Ronen, Ilana; Shemer-Elkiyam, Tal
2015-01-01
The advantages of learning communities focused on analyzing social issues and educational repercussions in the field are presented in this study. The research examines the contribution of a learning community to enhancing student teachers' responsibility and their social involvement. The assumption was that participating in learning community…
DOT National Transportation Integrated Search
2000-03-01
Many ITS projects are stand-alone in nature, and do not have to be procured under rules for construction. The installation of field devices and communications infrastructure often meets the definition of construction. However, if a project involves t...
Observer perspective imagery with stuttering.
Lowe, Robyn; Menzies, Ross; Packman, Ann; O'Brian, Sue; Onslow, Mark
2015-01-01
Adults who stutter are at risk of developing a range of psychological conditions. Social anxiety disorder is the most common anxiety disorder associated with stuttering. Observer perspective imagery is one cognitive process involved in the maintenance of some anxiety disorders. This involves viewing images as if looking at the self from the perspective of another. In contrast, the field perspective involves looking out from the self at the surrounding environment. The purpose of this study was to assess the presence of observer perspective imagery with stuttering. The authors administered the Hackmann, Surawy and Clark (1998) semi-structured interview to 30 adults who stutter and 30 controls. Group images and impressions were compared for frequency, perspective recalled and emotional valence. The stuttering group was significantly more likely than controls to recall images and impressions from an observer rather than a field perspective for anxious situations. It is possible the present results could reflect the same attentional processing bias that occurs with anxiety disorders in the non-stuttering population. These preliminary results provide an explanation for the persistence of conditions such as social anxiety disorder with stuttering. Clinical implications are discussed.
NASA Technical Reports Server (NTRS)
Feng, Wanda; Evans, Cynthia; Gruener, John; Eppler, Dean
2014-01-01
Geologic mapping involves interpreting relationships between identifiable units and landforms to understand the formative history of a region. Traditional field techniques are used to accomplish this on Earth. Mapping proves more challenging for other planets, which are studied primarily by orbital remote sensing and, less frequently, by robotic and human surface exploration. Systematic comparative assessments of geologic maps created by traditional mapping versus photogeology together with data from planned traverses are limited. The objective of this project is to produce a geologic map from data collected on the Desert Research and Technology Studies (RATS) 2010 analog mission using Apollo-style traverses in conjunction with remote sensing data. This map is compared with a geologic map produced using standard field techniques.
What's the use of land? (a secondary school social studies project)
NASA Technical Reports Server (NTRS)
1976-01-01
The concept of a student land use survey was discussed with the curriculum development team of the Jefferson County Public Schools in Colorado. In these discussions it soon became apparent that the curriculum potentials included much more than a classroom activity involving mapping the features on the ground in the area of study. A new flood control dam to be located in the area of Denver, Colorado, became the central topic in a program involving a wide variety of curriculum fields, such as mapmaking, local community history, physical geography, mathematics, and environmental studies. Consequently, a prototype of a multidisciplinary unit concept was developed for later incorporation by the Jefferson County curriculum team.
M.U.S.T. 2007 Summer Research Project at NASA's KSC MILA Facility
NASA Technical Reports Server (NTRS)
PintoRey, Christian R.
2007-01-01
The summer research activity at Kennedy Space Center (KSC) aims to introduce the student to the basic principles in their field of study. While at KSC, a specific research project awaits the student to complete. As an Aeronautical Engineering student, my assigned project is to assist the cognizant engineer, Mr. Troy Hamilton, in the six engineering phases for replacing the Ponce De Leon (PDL)4.3M Antenna Control Unit (ACU). Although the project mainly requires the attention of two engineers and two students, it also involves the participation of many colleagues at various points during the course of the engineering change (EC). Since the PDL 4.3M ACU engineering change makes both hardware and software changes, it calls upon the expertise of a Hardware Engineer as well as a Software Engineer. As students, Mr. Jeremy Bresette and I have worked side by side with the engineers, gaining invaluable experience. We work in two teams, the hardware team and the software team, On certain tasks, we assist the engineers, while on others we assume their roles. By diligently working in this fashion, we are learning how to communicate effectively as professionals, despite the fact that we are studying different engineering fields. This project has been a great fit for my field of study, as it has highly improved my awareness of the many critical tasks involved in carrying out an engineering project.
Cocaine phenomenology study: results of a third in a series of field trials
NASA Astrophysics Data System (ADS)
Su, Chih-Wu; Rigdon, Stephen W.; Ricard, Steve; Hoglund, David E.; Drolet, Gerry; Neudorfl, Pavel; Hupe, Michael; Kunz, Terry D.; Ulvick, Sydney J.; Demirgian, Jack C.; Shier, Patrick; Wingo, Jeff J.
1997-01-01
To form an understanding of the environment in which non- intrusive detection and inspection technologies are required to operate, the Narcotic Detection Technology assessment Team has undertaken a series of field studies. These field studies have focused on the phenomenology, fate and behavior of narcotic residue in real world environments. The overall goal of the tests is to give Law Enforcement officers the ability to accurately differentiate between individuals involved in the smuggling process and individuals innocently contaminated with narcotics. The latest filed study in this series was conducted in Miami, FL in February 1996. The field study comprised several individual tests. The first was a contamination and transfer study which focuses on human contamination resulting from contact with actual kilos of cocaine and the mechanism by which this contamination transfers to surrounding objects, if at all. The second was a secondary contamination study which focused on determining the conditions under which cocaine contamination transfers from objects touched by individuals who handled narcotics to innocent passerbys. The third was a persistence study which focused on the persistence of cocaine contamination on people under a variety of conditions. An overview of the tests and their preliminary results will be discussed.
Abbiati, Giovanni; Argentin, Gianluca; Barone, Carlo; Schizzerotto, Antonio
2017-11-29
Our contribution assesses the role of information barriers for patterns of participation in Higher Education (HE) and the related social inequalities. For this purpose, we developed a large-scale clustered randomised experiment involving over 9,000 high school seniors from 62 Italian schools. We designed a counseling intervention to correct student misperceptions of the profitability of HE, that is, the costs, economic returns and chances of success of investments in different tertiary programs. We employed a longitudinal survey to test whether treated students' educational trajectories evolved differently relative to a control group. We find that, overall, treated students enrolled less often in less remunerative fields of study in favour of postsecondary vocational programmes. Most importantly, this effect varied substantially by parental social class and level of education. The shift towards vocational programmes was mainly due to the offspring of low-educated parents; in contrast, children of tertiary graduates increased their participation in more rewarding university fields. Similarly, the redistribution from weak fields to vocational programmes mainly involved the children of the petty bourgeoisie and the working class, while upper class students invested in more rewarding university fields. We argue that the status-maintenance model proposed by Breen and Goldthorpe can explain these socially differentiated treatment effects. Overall, our results challenge the claim that student misperceptions contribute to horizontal inequalities in access to HE. © London School of Economics and Political Science 2017.
REGIONAL-SCALE WIND FIELD CLASSIFICATION EMPLOYING CLUSTER ANALYSIS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Glascoe, L G; Glaser, R E; Chin, H S
2004-06-17
The classification of time-varying multivariate regional-scale wind fields at a specific location can assist event planning as well as consequence and risk analysis. Further, wind field classification involves data transformation and inference techniques that effectively characterize stochastic wind field variation. Such a classification scheme is potentially useful for addressing overall atmospheric transport uncertainty and meteorological parameter sensitivity issues. Different methods to classify wind fields over a location include the principal component analysis of wind data (e.g., Hardy and Walton, 1978) and the use of cluster analysis for wind data (e.g., Green et al., 1992; Kaufmann and Weber, 1996). The goalmore » of this study is to use a clustering method to classify the winds of a gridded data set, i.e, from meteorological simulations generated by a forecast model.« less
Chiral magnetic effect in the presence of electroweak interactions as a quasiclassical phenomenon
NASA Astrophysics Data System (ADS)
Dvornikov, Maxim; Semikoz, Victor B.
2018-03-01
We elaborate the quasiclassical approach to obtain the modified chiral magnetic effect (CME) in the case when the massless charged fermions interact with electromagnetic fields and the background matter by the electroweak forces. The derivation of the anomalous current along the external magnetic field involves the study of the energy density evolution of chiral particles in parallel electric and magnetic fields. We consider both the particle acceleration by the external electric field and the contribution of the Adler anomaly. The condition of the validity of this method for the derivation of the CME is formulated. We obtain the expression for the electric current along the external magnetic field, which appears to coincide with our previous results based on the purely quantum approach. Our results are compared with the findings of other authors.
NASA Astrophysics Data System (ADS)
Saveriades, George
This PhD dissertation focuses on the study of the effects of magnetic exposure on biological systems using amperometry techniques and viability assays. In our prior work based on the cyclotron resonance model, chromaffin cells in physiological saline and Ca2+-free media were exposed for 5 minutes to a 2.7 muT magnetic field, with frequency sweeps going from 30-60 Hz (targeting several ions involved in exocytosis) and 44-48 Hz (targeting specifically Ca2+ ions), with noticeable effects on exocytosis. The present study extended the work on chromaffin cells by covering frequency sweeps for different ions, manipulating the time of exposure and the strength of the magnetic field. Furthermore, amperometry was conducted on acute coronal brain slices, to demonstrate that the recorded effects could be measured on neuronal tissue. The viability of chromaffin cells and primary neuronal cultures exposed to magnetic fields was also addressed. The results demonstrate that cellular exocytosis is sensitive to the frequency of the magnetic field it is exposed to, the strength of the magnetic field and the duration of exposure. No significant effects were established with regards to the viability of the cells exposed to magnetic fields.
Informational analysis involving application of complex information system
NASA Astrophysics Data System (ADS)
Ciupak, Clébia; Vanti, Adolfo Alberto; Balloni, Antonio José; Espin, Rafael
The aim of the present research is performing an informal analysis for internal audit involving the application of complex information system based on fuzzy logic. The same has been applied in internal audit involving the integration of the accounting field into the information systems field. The technological advancements can provide improvements to the work performed by the internal audit. Thus we aim to find, in the complex information systems, priorities for the work of internal audit of a high importance Private Institution of Higher Education. The applied method is quali-quantitative, as from the definition of strategic linguistic variables it was possible to transform them into quantitative with the matrix intersection. By means of a case study, where data were collected via interview with the Administrative Pro-Rector, who takes part at the elaboration of the strategic planning of the institution, it was possible to infer analysis concerning points which must be prioritized at the internal audit work. We emphasize that the priorities were identified when processed in a system (of academic use). From the study we can conclude that, starting from these information systems, audit can identify priorities on its work program. Along with plans and strategic objectives of the enterprise, the internal auditor can define operational procedures to work in favor of the attainment of the objectives of the organization.
Older Adult Multitasking Performance Using a Gaze-Contingent Useful Field of View.
Ward, Nathan; Gaspar, John G; Neider, Mark B; Crowell, James; Carbonari, Ronald; Kaczmarski, Hank; Ringer, Ryan V; Johnson, Aaron P; Loschky, Lester C; Kramer, Arthur F
2018-03-01
Objective We implemented a gaze-contingent useful field of view paradigm to examine older adult multitasking performance in a simulated driving environment. Background Multitasking refers to the ability to manage multiple simultaneous streams of information. Recent work suggests that multitasking declines with age, yet the mechanisms supporting these declines are still debated. One possible framework to better understand this phenomenon is the useful field of view, or the area in the visual field where information can be attended and processed. In particular, the useful field of view allows for the discrimination of two competing theories of real-time multitasking, a general interference account and a tunneling account. Methods Twenty-five older adult subjects completed a useful field of view task that involved discriminating the orientation of lines in gaze-contingent Gabor patches appearing at varying eccentricities (based on distance from the fovea) as they operated a vehicle in a driving simulator. In half of the driving scenarios, subjects also completed an auditory two-back task to manipulate cognitive workload, and during some trials, wind was introduced as a means to alter general driving difficulty. Results Consistent with prior work, indices of driving performance were sensitive to both wind and workload. Interestingly, we also observed a decline in Gabor patch discrimination accuracy under high cognitive workload regardless of eccentricity, which provides support for a general interference account of multitasking. Conclusion The results showed that our gaze-contingent useful field of view paradigm was able to successfully examine older adult multitasking performance in a simulated driving environment. Application This study represents the first attempt to successfully measure dynamic changes in the useful field of view for older adults completing a multitasking scenario involving driving.
Nigam, Amit
2013-06-01
Clinical guidelines are important tools for managing health care quality. Research on the origins of guidelines primarily focuses on the institutional causes of their emergence and growth. Individual medical researchers, however, have played important roles. This paper develops knowledge of the role of individual medical researchers in advancing guidelines, and of how researchers' efforts were enabled or constrained by broader institutional changes. Drawing on an analytical case study focused on the role of Kerr White, John Wennberg, and Robert Brook, it shows that guidelines were a product of the interplay between institutional change in the medical field and actions by individual researchers, acting as institutional entrepreneurs. Increased government involvement in the health care field triggered the involvement of a range of new actors in health care. These new organizations created a context that allowed individual researchers to advance guidelines by creating job opportunities, providing research funding, and creating opportunities for researchers to engage with the policy process. Individual researchers availed of this context to both advance their ideas, and to draw new actors into the field. Copyright © 2013. Published by Elsevier Ltd.
Early-\\x90stage Electrical Breakdown involving Tunneling
NASA Astrophysics Data System (ADS)
Hjalmarson, Harold; Moore, Chris; Schultz, Peter; Bussman, Ezra; Scrymgeour, David; Hopkins, Matt
The early stage of electrical breakdown from a surface is assumed to involve field emission. In real-world applications, the electrical field is often assumed to be increased by geometrical effects. In addition to these enhancement effects, contamination by adsorbates can lead to reductions in the effective work functions. To develop a physics-based understanding beyond the use of these empirical effects, the field emission currents at early times are being computed and measured. The calculations involve a solution of the Boltzmann equation, and the measurements involve a scanning tunneling microscope. Early results from this collaborative theoretical-experimental project will be described in this presentation. The presentation will focus on results for an ideal system with an absence of geometrical effects. Sandia National Laboratories is a multi-mission laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Poreau, Brice
2016-01-01
Neurodegenerative disorders are involved in mortality and morbidity of every country. A high prevalence is estimated in Africa. Neurodegenerative disorders are defined by a progressive or self-limiting alteration of neurons implied in specific functional and anatomical functions. It encompasses a various range of clinical disorders from self-limiting to progressive. Focus on public health policies and scientific research is needed to understand the mechanisms to reduce this high prevalence. We use bibliometrics and mapping tools to explore the area studies and countries involved in scientific research on neurodegenerative disorders in Africa. We used two databases: Web of Science and Pubmed. We analyzed the journals, most cited articles, authors, publication years, organizations, funding agencies, countries and keywords in Web of Science Core collection database and publication years and Medical Subject Headings in Pubmed database. We mapped the data using VOSviewer. We accessed 44 articles published between 1975 and 2014 in Web of Science Core collection Database and 669 from Pubmed database. The majority of which were after 2006. The main countries involved in research on neurodegenerative disorders in Africa the USA, the United Kingdom, France and South Africa representing the main network collaboration. Clinical neurology and Genetics hereditary are the main Web of Science categories whereas Neurosciences and Biochemistry and Molecular Biology are the main Web of Science categories for the general search "neurodegenerative disorders" not restrained to Africa. This is confirmed by Medical Subject Headings analysis from Pubmed with one more area study: Treatment. Neurodegenerative disorders research is leaded by South Africa with a network involving the USA, the UK, as well as African countries such Zambia. The chief field that emerged was on patient and hereditary as well as treatment. Public health policies were lacking fields in research whereas prevalence is estimated to be important in every country. New 17 sustainable development goals of the United Nations could help in this way.
Use of LEED, Auger emission spectroscopy and field ion microscopy in microstructural studies
NASA Technical Reports Server (NTRS)
Ferrante, J.; Buckley, D. H.; Pepper, S. V.; Brainard, W. A.
1972-01-01
Surface research tools such as LEED, Auger emission spectroscopy analysis, and field ion microscopy are discussed. Examples of their use in studying adhesion, friction, wear, and lubrication presented. These tools have provided considerable insight into the basic nature of solid surface interactions. The transfer of metals from one surface to another at the atomic level has been observed and studied with each of these devices. The field ion microscope has been used to study polymer-metal interactions and Auger analysis to study the mechanism of polymer adhesion to metals. LEED and Auger analysis have identified surface segregation of alloying elements and indicated the influence of these elements in metallic adhesion. LEED and Auger analysis have assisted in adsorption studies in determining the structural arrangement and quantity of adsorbed species present in making an understanding of the influence of these species on adhesion possible. These devices are assisting in the furtherance of understanding of the fundamental mechanism involved in the adhesion, friction, wear, and lubrication processes.
Football helmet drop tests on different fields using an instrumented Hybrid III head.
Viano, David C; Withnall, Chris; Wonnacott, Michael
2012-01-01
An instrumented Hybrid III head was placed in a Schutt ION 4D football helmet and dropped on different turfs to study field types and temperature on head responses. The head was dropped 0.91 and 1.83 m giving impacts of 4.2 and 6.0 m/s on nine different football fields (natural, Astroplay, Fieldturf, or Gameday turfs) at turf temperatures of -2.7 to 23.9 °C. Six repeat tests were conducted for each surface at 0.3 m (1') intervals. The Hybrid III was instrumented with triaxial accelerometers to determine head responses for the different playing surfaces. For the 0.91-m drops, peak head acceleration varied from 63.3 to 117.1 g and HIC(15) from 195 to 478 with the different playing surfaces. The lowest response was with Astroplay, followed by the engineered natural turf. Gameday and Fieldturf involved higher responses. The differences between surfaces decreased in the 1.83 m tests. The cold weather testing involved higher accelerations, HIC(15) and delta V for each surface. The helmet drop test used in this study provides a simple and convenient means of evaluating the compliance and energy absorption of football playing surfaces. The type and temperature of the playing surface influence head responses.
Attractor scenarios and superluminal signals in k-essence cosmology
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kang, Jin U; Arnold Sommerfeld Center, Department of Physics, Ludwig-Maximilians University, Theresienstrasse 37, 80333 Munich; Vanchurin, Vitaly
Cosmological scenarios with k-essence are invoked in order to explain the observed late-time acceleration of the Universe. These scenarios avoid the need for fine-tuned initial conditions (the 'coincidence problem') because of the attractorlike dynamics of the k-essence field {phi}. It was recently shown that all k-essence scenarios with Lagrangians p=L(X){phi}{sup -2}, where X{identical_to}(1/2){phi}{sub ,{mu}}{phi}{sup ,{mu}}, necessarily involve an epoch where perturbations of {phi} propagate faster than light (the 'no-go theorem'). We carry out a comprehensive study of attractorlike cosmological solutions ('trackers') involving a k-essence scalar field {phi} and another matter component. The result of this study is a complete classificationmore » of k-essence Lagrangians that admit asymptotically stable tracking solutions, among all Lagrangians of the form p=K({phi})L(X). Using this classification, we select the class of models that describe the late-time acceleration and avoid the coincidence problem through the tracking mechanism. An analogous 'no-go theorem' still holds for this class of models, indicating the existence of a superluminal epoch. In the context of k-essence cosmology, the superluminal epoch does not lead to causality violations. We discuss the implications of superluminal signal propagation for possible causality violations in Lorentz-invariant field theories.« less
In vitro study of the effects of ELF electric fields on gene expression in human epidermal cells.
Collard, Jean-Francois; Mertens, Benjamin; Hinsenkamp, Maurice
2011-01-01
An acceleration of differentiation, at the expense of proliferation, is observed after exposure of various biological models to low frequency and low amplitude electric and electromagnetic fields. Following these results showing significant modifications, we try to identify the biological mechanism involved at the cell level through microarray screening. For this study, we use epidermis cultures harvested from human abdominoplasty. Two platinum electrodes are used to apply the electric signal. The gene expressions of 38,500 well-characterized human genes are analyzed using Affymetrix(®) microarray U133 Plus 2.0 chips. The protocol is repeated on three different patients. After three periods of exposure, a total of 24 chips have been processed. After the application of ELF electric fields, the microarray analysis confirms a modification of the gene expression of epidermis cells. Particularly, four up-regulated genes (DKK1, TXNRD1, ATF3, and MME) and one down-regulated gene (MACF1) are involved in the regulation of proliferation and differentiation. Expression of these five genes was also confirmed by real-time rtPCR in all samples used for microarray analysis. These results corroborate an acceleration of cell differentiation at the expense of cell proliferation. © 2010 Wiley-Liss, Inc.
Towards a Unified Approach to Information Integration - A review paper on data/information fusion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Whitney, Paul D.; Posse, Christian; Lei, Xingye C.
2005-10-14
Information or data fusion of data from different sources are ubiquitous in many applications, from epidemiology, medical, biological, political, and intelligence to military applications. Data fusion involves integration of spectral, imaging, text, and many other sensor data. For example, in epidemiology, information is often obtained based on many studies conducted by different researchers at different regions with different protocols. In the medical field, the diagnosis of a disease is often based on imaging (MRI, X-Ray, CT), clinical examination, and lab results. In the biological field, information is obtained based on studies conducted on many different species. In military field, informationmore » is obtained based on data from radar sensors, text messages, chemical biological sensor, acoustic sensor, optical warning and many other sources. Many methodologies are used in the data integration process, from classical, Bayesian, to evidence based expert systems. The implementation of the data integration ranges from pure software design to a mixture of software and hardware. In this review we summarize the methodologies and implementations of data fusion process, and illustrate in more detail the methodologies involved in three examples. We propose a unified multi-stage and multi-path mapping approach to the data fusion process, and point out future prospects and challenges.« less
Respirable dust and respirable silica exposure in Ontario gold mines.
Verma, Dave K; Rajhans, Gyan S; Malik, Om P; des Tombe, Karen
2014-01-01
A comprehensive survey of respirable dust and respirable silica in Ontario gold mines was conducted by the Ontario Ministry of Labor during 1978-1979. The aim was to assess the feasibility of introducing gravimetric sampling to replace the assessment method which used konimeters, a device which gave results in terms of number of particles per cubic centimeter (ppcc) of air. The study involved both laboratory and field assessments. The field assessment involved measurement of airborne respirable dust and respirable silica at all eight operating gold mines of the time. This article describes the details of the field assessment. A total of 288 long-term (7-8 hr) personal respirable dust air samples were collected from seven occupational categories in eight gold mines. The respirable silica (α-quartz) was determined by x-ray diffraction method. The results show that during 1978-1979, the industry wide mean respirable dust was about 1 mg/m(3), and the mean respirable silica was 0.08 mg/m(3.)The mean% silica in respirable dust was 7.5%. The data set would be useful in future epidemiological and health studies, as well as in assessment of workers' compensation claims for occupational diseases such as silicosis, chronic obstructive pulmonary disease (COPD), and autoimmune diseases such as renal disease and rheumatoid arthritis.
Weak-field multiphoton femtosecond coherent control in the single-cycle regime.
Chuntonov, Lev; Fleischer, Avner; Amitay, Zohar
2011-03-28
Weak-field coherent phase control of atomic non-resonant multiphoton excitation induced by shaped femtosecond pulses is studied theoretically in the single-cycle regime. The carrier-envelope phase (CEP) of the pulse, which in the multi-cycle regime does not play any control role, is shown here to be a new effective control parameter that its effect is highly sensitive to the spectral position of the ultrabroad spectrum. Rationally chosen position of the ultrabroadband spectrum coherently induces several groups of multiphoton transitions from the ground state to the excited state of the system: transitions involving only absorbed photons as well as Raman transitions involving both absorbed and emitted photons. The intra-group interference is controlled by the relative spectral phase of the different frequency components of the pulse, while the inter-group interference is controlled jointly by the CEP and the relative spectral phase. Specifically, non-resonant two- and three-photon excitation is studied in a simple model system within the perturbative frequency-domain framework. The developed intuition is then applied to weak-field multiphoton excitation of atomic cesium (Cs), where the simplified model is verified by non-perturbative numerical solution of the time-dependent Schrödinger equation. We expect this work to serve as a basis for a new line of femtosecond coherent control experiments.
O'Connell, Caitlin; Ho, Leon C; Murphy, Matthew C; Conner, Ian P; Wollstein, Gadi; Cham, Rakie; Chan, Kevin C
2016-11-09
Human visual performance has been observed to show superiority in localized regions of the visual field across many classes of stimuli. However, the underlying neural mechanisms remain unclear. This study aims to determine whether the visual information processing in the human brain is dependent on the location of stimuli in the visual field and the corresponding neuroarchitecture using blood-oxygenation-level-dependent functional MRI (fMRI) and diffusion kurtosis MRI, respectively, in 15 healthy individuals at 3 T. In fMRI, visual stimulation to the lower hemifield showed stronger brain responses and larger brain activation volumes than the upper hemifield, indicative of the differential sensitivity of the human brain across the visual field. In diffusion kurtosis MRI, the brain regions mapping to the lower visual field showed higher mean kurtosis, but not fractional anisotropy or mean diffusivity compared with the upper visual field. These results suggested the different distributions of microstructural organization across visual field brain representations. There was also a strong positive relationship between diffusion kurtosis and fMRI responses in the lower field brain representations. In summary, this study suggested the structural and functional brain involvements in the asymmetry of visual field responses in humans, and is important to the neurophysiological and psychological understanding of human visual information processing.
Congenital deafness affects deep layers in primary and secondary auditory cortex
Berger, Christoph; Kühne, Daniela; Scheper, Verena
2017-01-01
Abstract Congenital deafness leads to functional deficits in the auditory cortex for which early cochlear implantation can effectively compensate. Most of these deficits have been demonstrated functionally. Furthermore, the majority of previous studies on deafness have involved the primary auditory cortex; knowledge of higher‐order areas is limited to effects of cross‐modal reorganization. In this study, we compared the cortical cytoarchitecture of four cortical areas in adult hearing and congenitally deaf cats (CDCs): the primary auditory field A1, two secondary auditory fields, namely the dorsal zone and second auditory field (A2); and a reference visual association field (area 7) in the same section stained either using Nissl or SMI‐32 antibodies. The general cytoarchitectonic pattern and the area‐specific characteristics in the auditory cortex remained unchanged in animals with congenital deafness. Whereas area 7 did not differ between the groups investigated, all auditory fields were slightly thinner in CDCs, this being caused by reduced thickness of layers IV–VI. The study documents that, while the cytoarchitectonic patterns are in general independent of sensory experience, reduced layer thickness is observed in both primary and higher‐order auditory fields in layer IV and infragranular layers. The study demonstrates differences in effects of congenital deafness between supragranular and other cortical layers, but similar dystrophic effects in all investigated auditory fields. PMID:28643417
NASA Astrophysics Data System (ADS)
Coppi, Bruno
2012-10-01
A clear theoretical framework to describe how magnetic fields are generated and amplified is provided by the magneto-gravitational modes that involve both differential rotation and gravity and for which other factors such as temperature gradients can contribute to their excitation. These modes are shown to be important for the evolution of plasma disks surrounding black holes.footnotetextB. Coppi, Phys. Plasmas 18, 032901 (2011) Non-linear and axi-symmetric plasmas and associated field configurations are found under stationary conditions that do not involve the presence of a pre-existing ``seed'' magnetic field unlike other configurations found previously.footnotetextIbid. The relevant magnetic energy density is of the order of the gravitationally confined plasma pressure. The solitary plasma rings that characterize these configurations are localized radially over regions with vanishing differential rotation and can be envisioned as the saturated state of magneto-gravitational modes. The ``source'' of these configurations is the combination of the gravitational force and of the plasma density gradient orthogonal to it.
PCOR, CER, and CBPR: alphabet soup or complementary fields of health research?
Burke, Jessica G; Jones, Jennifer; Yonas, Michael; Guizzetti, Lisa; Virata, Maria C; Costlow, Monica; Morton, Sally C; Elizabeth, Miller
2013-12-01
Comparative effectiveness research (CER) and community- based participatory research (CBPR) are two fields of research that do not have a history of strong collaboration. However, CER and CBPR researchers could benefit from interdisciplinary collaboration to design and implement relevant, timely, action-oriented research. This commentary explores field-specific definitions of stakeholders and then outlines various roles stakeholders might play within grant-funded research. Questions such as "What stakeholders should be involved?" and "How are stakeholders involved?" are addressed. The goal of this commentary is to highlight how the expertise and experiences of CBPR investigators can enhance the field of CER and to describe strategies for encouraging stakeholder involvement in CER research through the lens of CBPR. It is recommended that a team-based approach to conducting stakeholder-engaged CER encourages multiple stakeholders and "end users" to contribute their diverse expertise to the research process and contributes to the development of research with an increased likelihood of improving patient health and healthcare. © 2013 Wiley Periodicals, Inc.
MHD processes in the outer heliosphere
NASA Technical Reports Server (NTRS)
Burlaga, L. F.
1984-01-01
The magnetic field measurements from Voyager and the magnetohydrodynamic (MHD) processes in the outer heliosphere are reviewed. A bibliography of the experimental and theoretical work concerning magnetic fields and plasmas observed in the outer heliosphere is given. Emphasis in this review is on basic concepts and dynamical processes involving the magnetic field. The theory that serves to explain and unify the interplanetary magnetic field and plasma observations is magnetohydrodynamics. Basic physical processes and observations that relate directly to solutions of the MHD equations are emphasized, but obtaining solutions of this complex system of equations involves various assumptions and approximations. The spatial and temporal complexity of the outer heliosphere and some approaches for dealing with this complexity are discussed.
Kunimatsu-Sanuki, Shiho; Iwase, Aiko; Araie, Makoto; Aoki, Yuki; Hara, Takeshi; Nakazawa, Toru; Yamaguchi, Takuhiro; Ono, Hiroshi; Sanuki, Tomoyuki; Itoh, Makoto
2015-01-01
Objective To assess the driving fitness of patients with glaucoma by identifying specific areas and degrees of visual field impairment that threaten safe driving. Design Case–control study. Setting, and participants This prospective study included 36 patients with advanced glaucoma, defined as Humphrey field analyzer (HFA; 24-2 SITA standard program) measurements of mean deviation in both eyes of worse than −12 dB, and 36 age-matched and driving exposure time-matched normal subjects. All participants underwent testing in a novel driving simulator (DS) system. Participants were recruited between September 2010 and January 2012. Main outcome measures The number of collisions with simulated hazards and braking response time in 14 DS scenarios was recorded. Monocular HFA 24-2 test results from both eyes were merged to calculate the binocular integrated visual field (IVF). The position of the IVF subfields in which the collision-involved patients had lower sensitivity than the collision-uninvolved patients was compared with the track of the hazard. The cut-off value to predict an elevated risk of collisions was determined, as were its sensitivity and specificity, with the area under the receiver operating characteristic (AUROC) curve. Results Patients with advanced glaucoma were involved in a significantly higher number of collisions in the DS than the age-matched and driving exposure time-matched normal subjects (119 vs 40, respectively, p<0.0001), especially in four specific DS scenarios. In these four scenarios, IVF sensitivity was significantly lower in the collision-involved patients than in the collision-uninvolved patients in subfields on or near the track of the simulated hazard (p<0.05). The subfields with the largest AUROC curve had values ranging from 0.72 to 0.91 and were located in the paracentral visual field just below the horizontal. Conclusions Our novel DS system effectively assessed visual impairment, showing that simulators may have future potential in educating patients. PMID:25724982
Harland, S; Legge, G E; Luebker, A
1998-03-01
Most people with low vision need magnification to read. Page navigation is the process of moving a magnifier during reading. Modern electronic technology can provide many alternatives for navigating through text. This study compared reading speeds for four methods of displaying text. The four methods varied in their page-navigation demands. The closed-circuit television (CCTV) and MOUSE methods involved manual navigation. The DRIFT method (horizontally drifting text) involved no manual navigation, but did involve both smooth-pursuit and saccadic eye movements. The rapid serial visual presentation (RSVP) method involved no manual navigation, and relatively few eye movements. There were 7 normal subjects and 12 low-vision subjects (7 with central-field loss, CFL group, and 5 with central fields intact, CFI group). The subjects read 70-word passages at speeds that yielded good comprehension. Taking the CCTV reading speed as a benchmark, neither the normal nor low-vision subjects had significantly different speeds with the MOUSE method. As expected from the reduced navigational demands, normal subjects read faster with the DRIFT method (85% faster) and the RSVP method (169%). The CFI group read significantly faster with DRIFT (43%) and RSVP (38%). The CFL group showed no significant differences in reading speed for the four methods.
Kamuya, Dorcas M; Theobald, Sally J; Munywoki, Patrick K; Koech, Dorothy; Geissler, Wenzel P; Molyneux, Sassy C
2013-01-01
Fieldworkers (FWs) are community members employed by research teams to support access to participants, address language barriers, and advise on culturally appropriate research conduct. The critical role that FWs play in studies, and the range of practical and ethical dilemmas associated with their involvement, is increasingly recognised. In this paper, we draw on qualitative observation and interview data collected alongside a six month basic science study which involved a team of FWs regularly visiting 47 participating households in their homes. The qualitative study documented how relationships between field workers and research participants were initiated, developed and evolved over the course of the study, the shifting dilemmas FWs faced and how they handled them. Even in this one case study, we see how the complex and evolving relationships between fieldworkers and study participants had important implications for consent processes, access to benefits and mutual understanding and trust. While the precise issues that FWs face are likely to depend on the type of research and the context in which that research is being conducted, we argue that appropriate support for field workers is a key requirement to strengthen ethical research practice and for the long term sustainability of research programmes. PMID:23433316
Study of Low Temperature Baking Effect on Field Emission on Nb Samples Treated by BEP, EP, and BCP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Andy Wu, Song Jin, Robert Rimmer, Xiang Yang Lu, K. Zhao, Laura MacIntyre, Robert Ike
Field emission is still one of the major obstacles facing Nb superconducting radio frequency (SRF) community for allowing Nb SRF cavities to reach routinely accelerating gradient of 35 MV/m that is required for the international linear collider. Nowadays, the well know low temperature backing at 120 oC for 48 hours is a common procedure used in the SRF community to improve the high field Q slope. However, some cavity production data have showed that the low temperature baking may induce field emission for cavities treated by EP. On the other hand, an earlier study of field emission on Nb flatmore » samples treated by BCP showed an opposite conclusion. In this presentation, the preliminary measurements of Nb flat samples treated by BEP, EP, and BCP via our unique home-made scanning field emission microscope before and after the low temperature baking are reported. Some correlations between surface smoothness and the number of the observed field emitters were found. The observed experimental results can be understood, at least partially, by a simple model that involves the change of the thickness of the pent-oxide layer on Nb surfaces.« less
Why Most Published Research Findings Are False
Ioannidis, John P. A.
2005-01-01
Summary There is increasing concern that most current published research findings are false. The probability that a research claim is true may depend on study power and bias, the number of other studies on the same question, and, importantly, the ratio of true to no relationships among the relationships probed in each scientific field. In this framework, a research finding is less likely to be true when the studies conducted in a field are smaller; when effect sizes are smaller; when there is a greater number and lesser preselection of tested relationships; where there is greater flexibility in designs, definitions, outcomes, and analytical modes; when there is greater financial and other interest and prejudice; and when more teams are involved in a scientific field in chase of statistical significance. Simulations show that for most study designs and settings, it is more likely for a research claim to be false than true. Moreover, for many current scientific fields, claimed research findings may often be simply accurate measures of the prevailing bias. In this essay, I discuss the implications of these problems for the conduct and interpretation of research. PMID:16060722
Sahaï, Aïsha; Pacherie, Elisabeth; Grynszpan, Ouriel; Berberian, Bruno
2017-01-01
Nowadays, interactions with others do not only involve human peers but also automated systems. Many studies suggest that the motor predictive systems that are engaged during action execution are also involved during joint actions with peers and during other human generated action observation. Indeed, the comparator model hypothesis suggests that the comparison between a predicted state and an estimated real state enables motor control, and by a similar functioning, understanding and anticipating observed actions. Such a mechanism allows making predictions about an ongoing action, and is essential to action regulation, especially during joint actions with peers. Interestingly, the same comparison process has been shown to be involved in the construction of an individual's sense of agency, both for self-generated and observed other human generated actions. However, the implication of such predictive mechanisms during interactions with machines is not consensual, probably due to the high heterogeneousness of the automata used in the experimentations, from very simplistic devices to full humanoid robots. The discrepancies that are observed during human/machine interactions could arise from the absence of action/observation matching abilities when interacting with traditional low-level automata. Consistently, the difficulties to build a joint agency with this kind of machines could stem from the same problem. In this context, we aim to review the studies investigating predictive mechanisms during social interactions with humans and with automated artificial systems. We will start by presenting human data that show the involvement of predictions in action control and in the sense of agency during social interactions. Thereafter, we will confront this literature with data from the robotic field. Finally, we will address the upcoming issues in the field of robotics related to automated systems aimed at acting as collaborative agents. PMID:29081744
Experiments and the Negotiation of Power in High School Theatre: A Response.
ERIC Educational Resources Information Center
van de Water, Manon
1999-01-01
Responds to an article in the same issue of this journal describing a high school play director's use of "democratic" directing methods. Explores questions about methodology and study design and the role of the researcher in examining her own practice. Argues that the study makes a strong contribution to the field, especially for those involved in…
ERIC Educational Resources Information Center
Genc, Zubeyde Sinem; Aydin, Fulya
2017-01-01
The purpose of this study is to investigate Turkish students' (n = 462) motivation and attitudes toward learning English as a foreign language at a state university in Turkey and the relation between their attitudes, motivation and the variables such as gender, parental involvement, their fields of study at university, and academic achievement. It…
ERIC Educational Resources Information Center
Marishane, Ramodikoe Nylon
2013-01-01
This study examines the management of school infrastructure in the context of the "no-fee schools" policy introduced in the South African education delivery system. Focusing on four rural schools, the study applied a qualitative method, which involved observation of infrastructure conditions prevailing at four selected schools and…
Structural Validity of the Polish Adaptation of the Picture-Based Value Survey for Children (PBVS-C)
ERIC Educational Resources Information Center
Cieciuch, Jan; Harasimczuk, Justyna; Doring, Anna K.
2013-01-01
Recent years have witnessed an increasing number of studies, also in the field of educational psychology, on values within the framework proposed by Schwartz, involving younger and younger respondents. A fresh impetus to studies on children's values was given by the Picture-Based Value Survey for Children (PBVS-C), which was developed by Doring…
Christiansen, Helena E.; Mehinto, Alvine C.; Yu, Fahong; Perry, Russell W.; Denslow, Nancy D.; Maule, Alec G.; Mesa, Matthew G.
2014-01-01
Toxic compounds such as organochlorine pesticides (OCs), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ether flame retardants (PBDEs) have been detected in fish, birds, and aquatic mammals that live in the Columbia River or use food resources from within the river. We developed a custom microarray for largescale suckers (Catostomus macrocheilus) and used it to investigate the molecular effects of contaminant exposure on wild fish in the Columbia River. Using Significance Analysis of Microarrays (SAM) we identified 72 probes representing 69 unique genes with expression patterns that correlated with hepatic tissue levels of OCs, PCBs, or PBDEs. These genes were involved in many biological processes previously shown to respond to contaminant exposure, including drug and lipid metabolism, apoptosis, cellular transport, oxidative stress, and cellular chaperone function. The relation between gene expression and contaminant concentration suggests that these genes may respond to environmental contaminant exposure and are promising candidates for further field and laboratory studies to develop biomarkers for monitoring exposure of wild fish to contaminant mixtures found in the Columbia River Basin. The array developed in this study could also be a useful tool for studies involving endangered sucker species and other sucker species used in contaminant research.
Gravitational waves from non-Abelian gauge fields at a tachyonic transition
NASA Astrophysics Data System (ADS)
Tranberg, Anders; Tähtinen, Sara; Weir, David J.
2018-04-01
We compute the gravitational wave spectrum from a tachyonic preheating transition of a Standard Model-like SU(2)-Higgs system. Tachyonic preheating involves exponentially growing IR modes, at scales as large as the horizon. Such a transition at the electroweak scale could be detectable by LISA, if these non-perturbatively large modes translate into non-linear dynamics sourcing gravitational waves. Through large-scale numerical simulations, we find that the spectrum of gravitational waves does not exhibit such IR features. Instead, we find two peaks corresponding to the Higgs and gauge field mass, respectively. We find that the gravitational wave production is reduced when adding non-Abelian gauge fields to a scalar-only theory, but increases when adding Abelian gauge fields. In particular, gauge fields suppress the gravitational wave spectrum in the IR. A tachyonic transition in the early Universe will therefore not be detectable by LISA, even if it involves non-Abelian gauge fields.
Summer Research Internships at Biosphere 2 Center
NASA Technical Reports Server (NTRS)
1998-01-01
Through the support of NASA's Mission to Planet Earth, Biosphere 2 Center hosted 10 research interns for a 10 week period during the summer of 1998. In addition, we were able to offer scholarships to 10 students for Columbia University summer field courses. Students participating in these programs were involved in numerous earth systems activities, collecting data in the field and conducting analyses in the laboratory. Students enrolled in the field program were expected to design independent research projects as part of their coursework. In addition to laboratory and field research, students participated in weekly research seminars by resident and visiting scientists. Field school students were involved in field trips exposing them to the geology and ecology of the region including Arizona Sonora Desert Museum, Mount Lemmon, Aravaipa Canyon and the Gulf of California. Interns participated in laboratory-based research. All students were expected to complete oral and written presentations of their work during the summer.
Including Psychology in Inclusive Pedagogy: Enriching the Dialogue?
ERIC Educational Resources Information Center
Kershner, Ruth
2016-01-01
Inclusive education is a complex field of study and practice that requires good communication and dialogue between all involved. Psychology has to some extent been marginalised in these educational dialogues. This is, in part, due to psychology's perceived heritage in the standardised testing that has been used to support the educational…
For biomarkers to be useful in assessing anthropogenic impacts in field studies involving aquatic organisms, they should not be affected by naturally occurring changes in environmental parameters such as salinity. This is especially important in estuarine envi...
Citizen Me: An Experiential Curriculum for Citizenship Education. Level: One.
ERIC Educational Resources Information Center
Loftin, Richard
Integrating concepts of basic citizenship education with community involvement, this experiential curriculum provides a means for developing decision making and critical thinking skills within the existing social studies curriculum in grade 1. Using short stories, field trips, and class discussions, the 11 lessons on responsibilities, rules,…
Setting the Course: Strategies for Writing Digital and Social Guidelines
ERIC Educational Resources Information Center
Pasquini, Laura A.
2016-01-01
This chapter describes how to establish social media guidelines and policies for colleges and universities effectively, based upon a field study of postsecondary education institutions representing 10 different countries. To further community interactions and social media involvement, this chapter will outline effective practical approaches for…
Business as a Site of Language Contact.
ERIC Educational Resources Information Center
Harris, Sandra; Bargiela-Chiappini, Francesca
2003-01-01
Discusses the field of language for business. Argues for redressing the balance of research into business as a site of language contact in favor of less well-represented languages and cultures through indigenous discourse studies, and notes the increasing frequency and importance of work involving Asian languages. (Author/VWL)
Vocational Education: Voices from the Field.
ERIC Educational Resources Information Center
Green, Annette; Boylan, Colin
Vocational education and training (VET) has been given greater emphasis in Australian schools with the inclusion of seven Framework courses that contribute to students' Higher School Certificate and also count in students' University Admissions Index scores. A study examined the perceptions of people involved in VET programs for year 11.…
Professional Satisfaction of Teachers from Kindergarten. Preliminary Study
ERIC Educational Resources Information Center
Anghelache, Valerica
2014-01-01
Professional development is a topic of great interest for all those who are involved in educational field, makers and teachers. It's approached closely related to organizational development, both representing a result of continuous changes in education. At individual level, professional development has both an internal determination (a need to…
ERIC Educational Resources Information Center
Mano, Quintino R.
2016-01-01
Accumulating evidence suggests that literacy acquisition involves developing sensitivity to the statistical regularities of the textual environment. To organize accumulating evidence and help guide future inquiry, this article integrates data from disparate fields of study and formalizes a new two-process framework for developing sensitivity to…
Certificates: Gateway to Gainful Employment and College Degrees
ERIC Educational Resources Information Center
Carnevale, Anthony P.; Rose, Stephen J.; Hanson, Andrew R.
2012-01-01
Certificates are recognition of completion of a course of study based on a specific field, usually associated with a limited set of occupations. Certificates differ from other kinds of labor market credentials such as industry-based certifications and licenses, which typically involve passing an examination to prove a specific competency,…
ERIC Educational Resources Information Center
Bukoski, Beth E.; Lewis, Tiffanie C.; Carpenter, Bradley W.; Berry, Matthew S.; Sanders, Kimberly N.
2015-01-01
Meaningful community involvement has been linked to enhancements in student achievement and quality of educational experiences. Assistant principals are positioned to build effective partnerships yet remain understudied in the leadership preparation field. This qualitative study investigated how assistant principals (N = 9) serving historically…
"Canadianizing" an American Communication Textbook.
ERIC Educational Resources Information Center
Maclennan, Jennifer M.
2000-01-01
Presents a study on the process involved in the "Canadianization" of U.S. textbooks for the domestic market. Explores whether disciplinary values have been shaped by the United States in the field of communication. Focuses on the experience of developing the Canadian edition of the book "Public Speaking: Strategies for Success"…
Is the Cerebellum Involved in Motor and Perceptual Timing: A Case Study.
1985-05-15
return to regular employment as a typist. *The visual fields and cranial nerves were intact. The extraocular movements wererfull and there was no nystagmus ...Her saccades were hypermetric, especially on gaze to the left. Examination of motor function in the upper extremities revealed normal strength
Implications of Ubiquitous Computing for the Social Studies Curriculum
ERIC Educational Resources Information Center
van Hover, Stephanie D.; Berson, Michael J.; Bolick, Cheryl Mason; Swan, Kathleen Owings
2004-01-01
In March 2002, members of the National Technology Leadership Initiative (NTLI) met in Charlottesville, Virginia to discuss the potential effects of ubiquitous computing on the field of education. Ubiquitous computing, or "on-demand availability of task-necessary computing power," involves providing every student with a handheld computer--a…
Ways That Preservice Teachers Integrate Children's Literature into Mathematics Lessons
ERIC Educational Resources Information Center
Rogers, Rachelle Meyer; Cooper, Sandi; Nesmith, Suzanne M.; Purdum-Cassidy, Barbara
2015-01-01
Children's literature involving mathematics provides a common, natural context for the sharing of mathematics. To learn more about how preservice teachers included children's literature in their mathematics lessons, a study was conducted over two semesters during a required field experience component of an undergraduate teacher education program.…
77 FR 19263 - Proposed Information Collection; Comment Request
Federal Register 2010, 2011, 2012, 2013, 2014
2012-03-30
... Veterans and Military Families in National Service. The Field Assessment will include interviews with Corporation-funded programs and projects that involve veterans and military family members as national service... implemented to engage and serve veterans and military families. The aim of the study is to begin to build...
Communicating Effectively in Japanese for Business. Second Year.
ERIC Educational Resources Information Center
Hijirida, Kyoko; Sato, Carrie N.
Designed for university students majoring in business with specific occupational goals involving the tourist industry, this textbook was developed to meet both academic and society needs by providing a clear relationship between the Japanese language class and the student's major field of study. The textbook focuses on three objectives: to produce…
Pilot-scale vadose zone microbial biobarriers removed nitrate leaching from a cattle corral
USDA-ARS?s Scientific Manuscript database
activities that involve animal wastes can result in the contamination of subsurface soils by nitrates. In saturated or nearly saturated soils microbial biobarriers are a common method used to remove contaminants from water. This field study was conducted beneath a cattle pen in northeast Colorado a...
A significant challenge in environmental studies is to determine the onset and extent of MTBE bioremediation at an affected site, which may involve indirect approaches such as microcosm verification of microbial activities at a given site. Stable isotopic fractionation is cha...
1987-10-01
Occupational Field . 12. A pattern of discreditable involvement with military or *- civilian authorities, notwithstanding the fact that such misconduct has...AUTHORITIES .... ......... 10-1 CHAPTER XI ....... FREEDOM OF EXPRESSION IN THE MILITARY ......... 11-1 CHAPTER XII . . . CLAIMS...2-3 0204 WHAT CONSTITUTES MISCONDUCT. .. ............. .. 2-4 A. General rule .. .. .............. ...... 2-4 *B. No military duty can require
Spaces for Learning: Development and Validation of the School Physical and Campus Environment Survey
ERIC Educational Resources Information Center
Zandvliet, David; Broekhuizen, Avril
2017-01-01
The study of learning environments involves describing educational contexts and identifying empirical relationships among subject matter (curriculum), teaching practices and other environmental variables. In recent years, this has become a growing field of academic inquiry within elementary, secondary and post-secondary research. Investigations of…
Aquaculture: A Course of Study for Sand Point Secondary School.
ERIC Educational Resources Information Center
Alaska State Dept. of Education, Juneau. Office of Public Information and Publications.
This program is designed to involve students in the economy of their community. It combines an interdisciplinary educational program with practical field and laboratory experience. This program provides opportunities in the area of aquaculture, controlled cultivation of marketable species and the total ecological corrections necessary to maintain…
Laboratory Characteristics in Technical Education.
ERIC Educational Resources Information Center
Ives, Quay D.
The research reported is intended to provide a body of information on technical-scientific shop and laboratory education in the field of technological education. The study seeks to address the dearth of organized information on the utilization of laboratories in the technical education context. Various programs involving use of laboratories are…
Lived-Positive Emotionality in Elementary Physical Education
ERIC Educational Resources Information Center
Stuhr, Paul T.; Sutherland, Sue; Ward, Phillip
2012-01-01
Teaching is an occupation that requires a considerable amount of emotional energy when interacting with students. Through in-depth interviews, field notes and journal entries the investigators examined the phenomenon of lived-positive emotionality (LPE) involving two physical education (PE) teachers. The purpose of this study was to determine the…
E-Portfolio Evaluation and Vocabulary Learning: Moving from Pedagogy to Andragogy
ERIC Educational Resources Information Center
Sharifi, Maryam; Soleimani, Hassan; Jafarigohar, Manoochehr
2017-01-01
Current trends in the field of educational technology indicate a shift in pedagogical assumptions and theoretical frameworks that favor active involvement of self-directed learners in a constructivist environment. This study probes the influence of electronic portfolio evaluation on vocabulary learning of Iranian university students and the…
Use of PRD1 bacteriophage in groundwater viral transport, inactivation, and attachment studies
Harvey, Ronald W.; Ryan, Joseph N.
2004-01-01
PRD1, an icosahedra-shaped, 62 nm (diameter), double-stranded DNA bacteriophage with an internal membrane, has emerged as an important model virus for studying the manner in which microorganisms are transported through a variety of groundwater environments. The popularity of this phage for use in transport studies involving geologic media is due, in part, to its relative stability over a range of temperatures and low degree of attachment in aquifer sediments. Laboratory and field investigations employing PRD1 are leading to a better understanding of viral attachment and transport behaviors in saturated geologic media and to improved methods for describing mathematically subsurface microbial transport at environmentally significant field scales. Radioisotopic labeling of PRD1 is facilitating additional information about the nature of viral interactions with solid surfaces in geologic media, the importance of iron oxide surfaces, and allowing differentiation between inactivation and attachment in field-scale tracer tests.
Magnetic fields around black holes
NASA Astrophysics Data System (ADS)
Garofalo, David A. G.
Active Galactic Nuclei are the most powerful long-lived objects in the universe. They are thought to harbor supermassive black holes that range from 1 million solar masses to 1000 times that value and possibly greater. Theory and observation are converging on a model for these objects that involves the conversion of gravitational potential energy of accreting gas to radiation as well as Poynting flux produced by the interaction of the rotating spacetime and the electromagnetic fields originating in the ionized accretion flow. The presence of black holes in astrophysics is taking center stage, with the output from AGN in various forms such as winds and jets influencing the formation and evolution of the host galaxy. This dissertation addresses some of the basic unanswered questions that plague our current understanding of how rotating black holes interact with their surrounding magnetized accretion disks to produce the enormous observed energy. Two magnetic configurations are examined. The first involves magnetic fields connecting the black hole with the inner accretion disk and the other involves large scale magnetic fields threading the disk and the hole. We study the effects of the former type by establishing the consequences that magnetic torques between the black hole and the inner accretion disk have on the energy dissipation profile. We attempt a plausible explanation to the observed "Deep Minimum" state in the Seyfert galaxy MCG-6- 30-15. For the latter type of magnetic geometry, we study the effects of the strength of the magnetic field threading the black hole within the context of the cherished Blandford & Znajek mechanism for black hole spin energy extraction. We begin by addressing the problem in the non-relativistic regime where we find that the black hole-threading magnetic field is stronger for greater disk thickness, larger magnetic Prandtl number, and for a larger accretion disk. We then study the problem in full relativity where we show that our Newtonian results are excellent approximations for slowly spinning black holes. We proceed to address the issue of the spin dependence of the Blandford & Znajek power. The result we choose to highlight is our finding that given the validity of our assumption for the dynamical behavior of the so-called plunge region in black hole accretors, rotating black holes produce maximum Poynting flux via the Blandford & Znajek process for a black hole spin parameter of about a [approximate] 0.8. This is contrary to the conventional claim that the maximum electromagnetic flux is achieved for highest black hole spin.
STORM-SEWER FLOW MEASUREMENT AND RECORDING SYSTEM.
Kilpatrick, Frederick A.; Kaehrle, William R.
1986-01-01
A comprehensive study and development of instruments and techniques for measuring all components of flow in a storm-sewer drainage system were undertaken by the U. S. Geological Survey under the sponsorship of FHWA. The study involved laboratory and field calibration and testing of measuring flumes, pipe insert meters, weirs, and electromagnetic velocity meters as well as the development and calibration of pneumatic bubbler and pressure transducer head-measuring systems. Tracer dilution and acoustic-flowmeter measurements were used in field verification tests. A single micrologger was used to record data from all the instruments and also to activate on command the electromagnetic velocity meter and tracer dilution systems.
Magnetic forces and localized resonances in electron transfer through quantum rings.
Poniedziałek, M R; Szafran, B
2010-11-24
We study the current flow through semiconductor quantum rings. In high magnetic fields the current is usually injected into the arm of the ring preferred by classical magnetic forces. However, for narrow magnetic field intervals that appear periodically on the magnetic field scale the current is injected into the other arm of the ring. We indicate that the appearance of the anomalous-non-classical-current circulation results from Fano interference involving localized resonant states. The identification of the Fano interference is based on the comparison of the solution of the scattering problem with the results of the stabilization method. The latter employs the bound-state type calculations and allows us to extract both the energy of metastable states localized within the ring and the width of resonances by analysis of the energy spectrum of a finite size system as a function of its length. The Fano resonances involving states of anomalous current circulation become extremely narrow on both the magnetic field and energy scales. This is consistent with the orientation of the Lorentz force that tends to keep the electron within the ring and thus increases the lifetime of the electron localization within the ring. Absence of periodic Fano resonances in electron transfer probability through a quantum ring containing an elastic scatterer is also explained.
Phased Array Ultrasound System for Planar Flow Mapping in Liquid Metals.
Mader, Kevin; Nauber, Richard; Galindo, Vladimir; Beyer, Hannes; Buttner, Lars; Eckert, Sven; Czarske, Jurgen
2017-09-01
Controllable magnetic fields can be used to optimize flows in technical and industrial processes involving liquid metals in order to improve quality and yield. However, experimental studies in magnetohydrodynamics often involve complex, turbulent flows and require planar, two-component (2c) velocity measurements through only one acoustical access. We present the phased array ultrasound Doppler velocimeter as a modular research platform for flow mapping in liquid metals. It combines the pulse wave Doppler method with the phased array technique to adaptively focus the ultrasound beam. This makes it possible to resolve smaller flow structures in planar measurements compared with fixed-beam sensors and enables 2c flow mapping with only one acoustical access via the cross beam technique. From simultaneously measured 2-D velocity fields, quantities for turbulence characterization can be derived. The capabilities of this measurement system are demonstrated through measurements in the alloy gallium-indium-tin at room temperature. The 2-D, 2c velocity measurements of a flow in a cubic vessel driven by a rotating magnetic field (RMF) with a spatial resolution of up to 2.2 mm are presented. The measurement results are in good agreement with a semianalytical simulation. As a highlight, two-point correlation functions of the velocity field for different magnitudes of the RMF are presented.
Canadian content at GU-ASCO 2014: Highlights of research involving Canadian researchers.
Kapoor, Anil
2014-03-01
The 2014 Genitourinary Cancers Symposium (GU-ASCO 2014) provided an opportunity for researchers from around the world to present their research in a variety of fields, including prostate, renal cell, penile, urethral and testicular cancers. Over the symposium's 3 days, Canadian researchers were well-represented, with a number of oral abstract podium presentations and many more research posters. The following section provides brief summaries of some of the most interesting work involving Canadians presented at GU-ASCO 2014 and a listing of all the studies that included contributions from Canadian researchers.
Particles trajectories in magnetic filaments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bret, A.; Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real
2015-07-15
The motion of a particle in a spatially harmonic magnetic field is a basic problem involved, for example, in the mechanism of formation of a collisionless shock. In such settings, it is generally reasoned that particles entering a Weibel generated turbulence are trapped inside it, provided their Larmor radius in the peak field is smaller than the field coherence length. The goal of this work is to put this heuristic conclusion on firm ground by studying, both analytically and numerically, such motion. A toy model is analyzed, consisting of a relativistic particle entering a region of space occupied by amore » spatially harmonic field. The particle penetrates the magnetic structure in a direction aligned with the magnetic filaments. Although the conclusions are not trivial, the main result is confirmed.« less
NASA Astrophysics Data System (ADS)
Deshmukh, Snehal D.; Déjardin, Pierre-Michel; Kalmykov, Yuri P.
2017-09-01
Analytical formulas for the electric birefringence response of interacting polar and anisotropically polarizable molecules due to a uniform alternating electric field are derived using Berne's forced rotational diffusion model [B. J. Berne, J. Chem. Phys. 62, 1154 (1975)] in the nonlinear version described by Warchol and Vaughan [J. Chem. Phys. 71, 502 (1979)]. It is found for noninteracting molecules that the signal consists of a frequency-dependent DC component superimposed on an oscillatory part with a frequency twice that of the AC driving field. However, unlike noninteracting molecules, the AC part strongly deviates from its dilute counterpart. This suggests a possible way of motivating new experimental studies of intermolecular interactions involving electro-optical methods and complementary nonlinear dielectric relaxation experiments.
Sheared E×B flow and plasma turbulence viscosity in a Reversed Field Pinch
NASA Astrophysics Data System (ADS)
Vianello, N.; Antoni, V.; Spada, E.; Spolaore, M.; Serianni, G.; Regnoli, G.; Zuin, M.; Cavazzana, R.; Bergsåker, H.; Cecconello, M.; Drake, J. R.
2004-11-01
The relationship between electromagnetic turbulence and sheared plasma flow in Reversed Field Pinch configuration is addressed. The momentum balance equation for a compressible plasma is considered and the terms involved are measured in the outer region of Extrap-T2R RFP device. It results that electrostatic fluctuations determine the plasma flow through the electrostatic component of Reynolds Stress tensor. This term involves spatial and temporal scales comparable to those of MHD activity. The derived experimental perpendicular viscosity is consistent with anomalous diffusion, the latter being discussed in terms of electrostatic turbulence background and coherent structures emerging from fluctuations. The results indicate a dynamical interplay between turbulence, anomalous transport and mean E×B profiles. The momentum balance has been studied also in non-stationary condition during the application of Pulsed Poloidal Current Drive, which is known to reduce the amplitude of MHD modes.
Choroidal Involvement in Acute Posterior Multifocal Placoid Pigment Epitheliopathy.
Mrejen, Sarah; Sarraf, David; Chexal, Saradha; Wald, Kenneth; Freund, K Bailey
2016-01-01
To evaluate choroidal involvement in acute posterior multifocal placoid pigment epitheliopathy (APMPPE). Retrospective study in five eyes of three patients evaluated through multimodal imaging, including enhanced-depth imaging optical coherence tomography (OCT), ultra-wide field color photography, fundus autofluorescence, and fluorescein angiography (FA). Choroidal thickness and structure were evaluated on OCT. During the acute phase, choroidal OCT showed choroidal thickening and a lucency at the level of the inner choroid. Subclinical lesions detected in the retinal periphery using wide-field retinal imaging were isoautofluorescent and corresponded to choriocapillaris filling-defects on FA. At final follow-up, all patients showed resolution of choroidal thickening and the inner choroidal lucency, as well as the disappearance of subclinical lesions. These results suggest a transient ischemic choroiditis in APMPPE that may lead to secondary permanent retinal pigment epithelium damage in the posterior pole but not in the retinal periphery. Copyright 2016, SLACK Incorporated.
BPS objects in D = 7 supergravity and their M-theory origin
NASA Astrophysics Data System (ADS)
Dibitetto, Giuseppe; Petri, Nicolò
2017-12-01
We study several different types of BPS flows within minimal N=1 , D = 7 supergravity with SU(2) gauge group and non-vanishing topological mass. After reviewing some known domain wall solutions involving only the metric and the ℝ+ scalar field, we move to considering more general flows involving a "dyonic" profile for the 3-form gauge potential. In this context, we consider flows featuring a Mkw3 as well as an AdS3 slicing, write down the corresponding flow equations, and integrate them analytically to obtain many examples of asymptotically AdS7 solutions in presence of a running 3-form. Furthermore, we move to adding the possibility of non-vanishing vector fields, find the new corresponding flows and integrate them numerically. Finally, we discuss the eleven-dimensional interpretation of the aforementioned solutions as effective descriptions of M2 - M5 bound states.
Wang, Xiaoyue; Miao, Chuanwang; Chen, Zhen; Li, Wanhu; Yuan, Shuanghu; Yu, Jinming; Hu, Xudong
2017-01-01
Chemoradiotherapy is the most common treatment for inoperable esophageal cancer. However, there is no consensus on the delineation of the clinical target volume. Elective nodal irradiation (ENI) is recommended for inoperable esophageal cancer. A few studies have reported a decrease in the incidence of radiation-related toxicity of involved-field irradiation (IFI) for esophageal cancer. A systematic review and pooled analysis were performed to determine whether IFI in definitive chemoradiotherapy was more beneficial than ENI for esophageal cancer. The results showed no significant differences in the overall survival and local control rates between the IFI and ENI arms. Meanwhile, the incidences of esophageal and lung toxicities were significantly decreased in the IFI arm. These results suggest that IFI is a feasible treatment option for locally advanced esophageal cancer, especially to minimize irradiation-related toxicity.
Wang, Xiaoyue; Miao, Chuanwang; Chen, Zhen; Li, Wanhu; Yuan, Shuanghu; Yu, Jinming; Hu, Xudong
2017-01-01
Chemoradiotherapy is the most common treatment for inoperable esophageal cancer. However, there is no consensus on the delineation of the clinical target volume. Elective nodal irradiation (ENI) is recommended for inoperable esophageal cancer. A few studies have reported a decrease in the incidence of radiation-related toxicity of involved-field irradiation (IFI) for esophageal cancer. A systematic review and pooled analysis were performed to determine whether IFI in definitive chemoradiotherapy was more beneficial than ENI for esophageal cancer. The results showed no significant differences in the overall survival and local control rates between the IFI and ENI arms. Meanwhile, the incidences of esophageal and lung toxicities were significantly decreased in the IFI arm. These results suggest that IFI is a feasible treatment option for locally advanced esophageal cancer, especially to minimize irradiation-related toxicity. PMID:28442917
Venoms, toxins and derivatives from the Brazilian fauna: valuable sources for drug discovery.
De Marco Almeida, Flávia; de Castro Pimenta, Adriano Monteiro; Oliveira, Mônica Cristina; De Lima, Maria Elena
2015-06-25
Animal venoms have been widely investigated throughout the world. The great number of biotechnological articles as well as patent applications in the field of drug discovery based on these compounds indicates how important the source is. This review presents a list of the most studied Brazilian venomous animal species and shows the most recent patent applications filed from 2000 to 2013, which comprise Brazilian venoms, toxins and derivatives. We analyze the data according to the species, the type of products claimed and the nationality of the inventors. Fifty-five patent applications were found, involving 8 genera. Crotalus, Lachesis, Bothrops and Loxosceles represented 78% of the patent applications. The other 22% were represented by Phoneutria, Tityus, Acanthoscurria and Phyllomedusa. Most of the inventions (42%) involved anticancer, immunomodulator or antimicrobial drugs, while 13% involved anti-venoms and vaccines, 11% involved hypotensive compositions, 9% involved antinociceptive and/or anti-inflammatory compositions, and the other 25% involved methods, kits or compositions for various purposes. Brazilian inventors filed 49% of the patent applications, but other countries, mainly the United States of America, Germany, Russia and France, also filed patent applications claiming products comprising venoms, toxins and/or derivatives from the Brazilian fauna. Brazil holds an important number of patent applications which mostly belong to universities and research institutes, but the pharmaceutical industry in this field is still weak in Brazil. Although, Brazilian venomous animal species have been reported in drug discovery throughout the world, many species remain to be explored as valuable and promising tools for drug discovery and development.
Karpov, D; Liu, Z; Rolo, T Dos Santos; Harder, R; Balachandran, P V; Xue, D; Lookman, T; Fohtung, E
2017-08-17
Topological defects of spontaneous polarization are extensively studied as templates for unique physical phenomena and in the design of reconfigurable electronic devices. Experimental investigations of the complex topologies of polarization have been limited to surface phenomena, which has restricted the probing of the dynamic volumetric domain morphology in operando. Here, we utilize Bragg coherent diffractive imaging of a single BaTiO 3 nanoparticle in a composite polymer/ferroelectric capacitor to study the behavior of a three-dimensional vortex formed due to competing interactions involving ferroelectric domains. Our investigation of the structural phase transitions under the influence of an external electric field shows a mobile vortex core exhibiting a reversible hysteretic transformation path. We also study the toroidal moment of the vortex under the action of the field. Our results open avenues for the study of the structure and evolution of polar vortices and other topological structures in operando in functional materials under cross field configurations.Imaging of topological states of matter such as vortex configurations has generally been limited to 2D surface effects. Here Karpov et al. study the volumetric structure and dynamics of a vortex core mediated by electric-field induced structural phase transition in a ferroelectric BaTiO 3 nanoparticle.
Noise squeezing of fields that bichromatically excite atoms in a cavity.
Li, Lingchao; Hu, Xiangming; Rao, Shi; Xu, Jun
2016-11-14
It is well known that bichromatic excitation on one common transition can tune the emission or absorption spectra of atoms due to the modulation frequency dependent non-linearities. However little attention has been focused on the quantum dynamics of fields under bichromatic excitation. Here we present dissipative effects on noise correlations of fields in bichromatic interactions with atoms in cavities. We first consider an ensemble of two-level atoms that interacts with the two cavity fields of different frequencies and considerable amplitudes. By transferring the atom-field nonlinearities to the dressed atoms we separate out the dissipative interactions of Bogoliubov modes with the dressed atoms. The Bogoliubov mode dissipation establishes stable two-photon processes of two involved fields and therefore leads to two-mode squeezing. As a generalization, we then consider an ensemble of three-level Λ atoms for cascade bichromatic interactions. We extract the Bogoliubov-like four-mode interactions, which establish a quadrilateral of the two-photon processes of four involved fields and thus result in four-mode squeezing.
Yu, Mi; Lee, Haeyoung
2018-03-06
Nurses' turnover intention is not just a result of their maladjustment to the field; it is an organizational issue. This study aimed to construct a structural model to verify the effects of new graduate nurses' work environment satisfaction, emotional labor, and burnout on their turnover intention, with consideration of resilience and job involvement, and to test the adequacy of the developed model. A cross-sectional study and a structural equation modelling approach were used. A nationwide survey was conducted of 371 new nurses who were working in hospitals for ≤18 months between July and October, 2014. The final model accounted for 40% of the variance in turnover intention. Emotional labor and burnout had a significant positive direct effect and an indirect effect on nurses' turnover intention. Resilience had a positive direct effect on job involvement. Job involvement had a negative direct effect on turnover intention. Resilience and job involvement mediated the effect of work environment satisfaction, emotional labor, and burnout on turnover intention. It is important to strengthen new graduate nurses' resilience in order to increase their job involvement and to reduce their turnover intention. © 2018 Japan Academy of Nursing Science.
ERIC Educational Resources Information Center
Perkinson, Betty J.
2009-01-01
The view that community college developmental studies educators have about the space in which they teach, any renovated or new spaces they were involved in designing, and the type of space in which they would like to teach is examined. The developmental studies educators are experts in their field, having completed The Kellogg Institute at…
Research Into the Role of Students’ Affective Domain While Learning Geology in Field Environments
NASA Astrophysics Data System (ADS)
Elkins, J.
2009-12-01
Existing research programs in field-based geocognition include assessment of cognitive, psychomotor, and affective domains. Assessment of the affective domain often involves the use of instruments and techniques uncommon to the geosciences. Research regarding the affective domain also commonly results in the collection and production of qualitative data that is difficult for geoscientists to analyze due to their lack of familiarity with these data sets. However, important information about students’ affective responses to learning in field environments can be obtained by using these methods. My research program focuses on data produced by students’ affective responses to field-based learning environments, primarily among students at the introductory level. For this research I developed a Likert-scale Novelty Space Survey, which presents student ‘novelty space’ (Orion and Hofstien, 1993) as a polygon; the larger the polygons, the more novelty students are experiencing. The axises for these polygons correspond to novelty domains involving geographic, social, cognitive, and psychological factors. In addition to the Novelty Space Survey, data which I have collected/generated includes focus group interviews on the role of recreational experiences in geology field programs. I have also collected data concerning the motivating factors that cause students to take photographs on field trips. The results of these studies give insight to the emotional responses students have to learning in the field and are important considerations for practitioners of teaching in these environments. Collaborative investigations among research programs that cross university departments and include multiple institutions is critical at this point in development of geocognition as a field due to unfamiliarity with cognitive science methodology by practitioners teaching geosciences and the dynamic nature of field work by cognitive scientists. However, combining the efforts of cognitive scientists and practitioners of geoscience teaching into research teams is a recommended strategy for understanding the role of the affective domain in student learning in field environments.
1986-11-01
Report Organization. .................... 7 *PART 11: CASE STUDIES .......................... 9 Teton Dam Failure Flood. ...................... 9...channel, (3) Laurel Run Dam , and (4) Stillhouse Hollow Dam . The Laurel Run and Teton case studies involved field data sets from actual dam failures. The...hypothetical prismatic channel case study used the Teton reservoir and dam data but replaced the complex Teton Valley geometry with a prismatic channel
Mumford, Michael D.; Antes, Alison L.; Caughron, Jared J.; Connelly, Shane; Beeler, Cheryl
2010-01-01
In the present study, 258 doctoral students working in the health, biological, and social sciences were asked to solve a series of field-relevant problems calling for creative thought. Proposed solutions to these problems were scored with respect to critical creative thinking skills such as problem definition, conceptual combination, and idea generation. Results indicated that health, biological, and social scientists differed with respect to their skill in executing various operations, or processes, involved in creative thought. Interestingly, no differences were observed as a function of the students’ level of experience. The implications of these findings for understanding cross-field, and cross-experience level, differences in creative thought are discussed. PMID:20936085
Zhang, Z C; Dou, D; Wang, X Y; Xie, D H; Yan, Z C
2017-02-20
We analyzed the data of application and funding projects of the National Natural Science Foundation of China (NSFC) during 2010-2016 in the field of burns and plastic surgery and summarized the NSFC funding pattern, the research hotspots, and weaknesses in this field. The NSFC has funded 460 projects in the field of burns and plastic surgery, with total funding of RMB 227.96 million. The scientific issues involved in the funding projects include orthotherapy against malformations, wound repair, basic research of burns, skin grafting, scars prevention, and regeneration of hair follicle and sweat glands. The research techniques involved in the funding projects are diversified. NSFC plays an important role in the scientific research and talents training in the field of burns and plastic surgery.
NASA Technical Reports Server (NTRS)
Davis, Douglas D.
2001-01-01
Over the time period of this NASA grant the PI has helped plan and execute the PEM-Tropics B field program. He has also helped organize and co-chair two data workshops which have focused on the detailed analysis of PEM-Tropics B data. His direct participation in these analyses has led to his involvement in 13 manuscripts, nine of which are in print, two in press, and two submitted. A complete list of papers is given.
NASA Technical Reports Server (NTRS)
Hankins, D. B.; Wake, W. H.
1981-01-01
The potential remote sensing user community is enormous, and the teaching and training tasks are even larger; however, some underlying principles may be synthesized and applied at all levels from elementary school children to sophisticated and knowledgeable adults. The basic rules applying to each of the six major elements of any training course and the underlying principle involved in each rule are summarized. The six identified major elements are: (1) field sites for problems and practice; (2) lectures and inside study; (3) learning materials and resources (the kit); (4) the field experience; (5) laboratory sessions; and (6) testing and evaluation.
Multimodel methods for optimal control of aeroacoustics.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chen, Guoquan; Collis, Samuel Scott
2005-01-01
A new multidomain/multiphysics computational framework for optimal control of aeroacoustic noise has been developed based on a near-field compressible Navier-Stokes solver coupled with a far-field linearized Euler solver both based on a discontinuous Galerkin formulation. In this approach, the coupling of near- and far-field domains is achieved by weakly enforcing continuity of normal fluxes across a coupling surface that encloses all nonlinearities and noise sources. For optimal control, gradient information is obtained by the solution of an appropriate adjoint problem that involves the propagation of adjoint information from the far-field to the near-field. This computational framework has been successfully appliedmore » to study optimal boundary-control of blade-vortex interaction, which is a significant noise source for helicopters on approach to landing. In the model-problem presented here, the noise propagated toward the ground is reduced by 12dB.« less
Job Involvement and Organizational Commitment of Employees of Prehospital Emergency Medical System
Rahati, Alireza; Sotudeh-Arani, Hossein; Adib-Hajbaghery, Mohsen; Rostami, Majid
2015-01-01
Background: Several studies are available on organizational commitment of employees in different organizations. However, the organizational commitment and job involvement of the employees in the prehospital emergency medical system (PEMS) of Iran have largely been ignored. Objectives: This study aimed to investigate the organizational commitment and job involvement of the employees of PEMS and the relationship between these two issues. Materials and Methods: This cross-sectional study was conducted on 160 employees of Kashan PEMS who were selected through a census method in 2014. A 3-part instrument was used in this study, including a demographic questionnaire, the Allen and Miller’s organizational commitment inventory, and the Lodahl and Kejner’s job involvement inventory. We used descriptive statistics, Spearman correlation coefficient, Kruskal-Wallis, Friedman, analysis of variance, and Tukey post hoc tests to analyze the data. Results: The mean job involvement and organizational commitment scores were 61.78 ± 10.69 and 73.89 ± 13.58, respectively. The mean scores of job involvement and organizational commitment were significantly different in subjects with different work experiences (P = 0.043 and P = 0.012, respectively). However, no significant differences were observed between the mean scores of organizational commitment and job involvement in subjects with different fields of study, different levels of interest in the profession, and various educational levels. A direct significant correlation was found between the total scores of organizational commitment and job involvement of workers in Kashan PEMS (r = 0.910, P < 0.001). Conclusions: This study showed that the employees in the Kashan PEMS obtained half of the score of organizational commitment and about two-thirds of the job involvement score. Therefore, the higher level managers of the emergency medical system are advised to implement some strategies to increase the employees’ job involvement and organizational commitment. PMID:26835470
48 CFR 35.007 - Solicitations.
Code of Federal Regulations, 2014 CFR
2014-10-01
... offeror's experience; (5) Pertinent novel ideas in the specific branch of science and technology involved... in the specific field of science or technology involved. Cognizant technical personnel should...
48 CFR 35.007 - Solicitations.
Code of Federal Regulations, 2013 CFR
2013-10-01
... offeror's experience; (5) Pertinent novel ideas in the specific branch of science and technology involved... in the specific field of science or technology involved. Cognizant technical personnel should...
48 CFR 35.007 - Solicitations.
Code of Federal Regulations, 2012 CFR
2012-10-01
... offeror's experience; (5) Pertinent novel ideas in the specific branch of science and technology involved... in the specific field of science or technology involved. Cognizant technical personnel should...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Weber, Damien C., E-mail: damien.weber@unige.ch; Johanson, Safora; Peguret, Nicolas
2011-10-01
Purpose: To assess the excess relative risk (ERR) of radiation-induced cancers (RIC) in female patients with Hodgkin lymphoma (HL) female patients treated with conformal (3DCRT), intensity modulated (IMRT), or volumetric modulated arc (RA) radiation therapy. Methods and Materials: Plans for 10 early-stage HL female patients were computed for 3DCRT, IMRT, and RA with involved field RT (IFRT) and involvednode RT (INRT) radiation fields. Organs at risk dose--volume histograms were computed and inter-compared for IFRT vs. INRT and 3DCRT vs. IMRT/RA, respectively. The ERR for cancer induction in breasts, lungs, and thyroid was estimated using both linear and nonlinear models. Results:more » The mean estimated ERR for breast, lung, and thyroid were significantly lower (p < 0.01) with INRT than with IFRT planning, regardless of the radiation delivery technique used, assuming a linear dose-risk relationship. We found that using the nonlinear model, the mean ERR values were significantly (p < 0.01) increased with IMRT or RA compared to those with 3DCRT planning for the breast, lung, and thyroid, using an IFRT paradigm. After INRT planning, IMRT or RA increased the risk of RIC for lung and thyroid only. Conclusions: In this comparative planning study, using a nonlinear dose--risk model, IMRT or RA increased the estimated risk of RIC for breast, lung, and thyroid for HL female patients. This study also suggests that INRT planning, compared to IFRT planning, may reduce the ERR of RIC when risk is predicted using a linear model. Observing the opposite effect, with a nonlinear model, however, questions the validity of these biologically parameterized models.« less
Science in the Wild: Technology Needs and Opportunities in Scientific Fieldwork
NASA Technical Reports Server (NTRS)
Guice, Jon; Hoffower, Heidi; Norvig, Peter (Technical Monitor)
1999-01-01
Considering that much contemporary natural science involves field expeditions, fieldwork is an under-studied topic. There is also little information technology specifically designed to support scientific fieldwork, aside from portable scientific instruments. This article describes a variety of fieldwork practices in an interdisciplinary research area, proposes a framework linking types of fieldwork to types of needs in information technology, and identifies promising opportunities for technology development. Technologies that are designed to support the integration of field observations and samples with laboratory work are likely to aid nearly all research teams who conduct fieldwork. However, technologies that support highly detailed representations of field sites will likely trigger the deepest changes in work practice. By way of illustration, we present brief case studies of how fieldwork is done today and how it might be conducted with the introduction of new information technologies.
Stam, Rianne
2014-06-01
Some of the strongest electromagnetic fields (EMF) are found in the workplace. A European Directive sets limits to workers' exposure to EMF. This review summarizes its origin and contents and compares magnetic field exposure levels in high-risk workplaces with the limits set in the revised Directive. Pubmed, Scopus, grey literature databases, and websites of organizations involved in occupational exposure measurements were searched. The focus was on EMF with frequencies up to 10 MHz, which can cause stimulation of the nervous system. Selected studies had to provide individual maximum exposure levels at the workplace, either in terms of the external magnetic field strength or flux density or as induced electric field strength or current density. Indicative action levels and the corresponding exposure limit values for magnetic fields in the revised European Directive will be higher than those in the previous version. Nevertheless, magnetic flux densities in excess of the action levels for peripheral nerve stimulation are reported for workers involved in welding, induction heating, transcranial magnetic stimulation, and magnetic resonance imaging (MRI). The corresponding health effects exposure limit values for the electric fields in the worker's body can be exceeded for welding and MRI, but calculations for induction heating and transcranial magnetic stimulation are lacking. Since the revised European Directive conditionally exempts MRI-related activities from the exposure limits, measures to reduce exposure may be necessary for welding, induction heating, and transcranial nerve stimulation. Since such measures can be complicated, there is a clear need for exposure databases for different workplace scenarios with significant EMF exposure and guidance on good practices. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
NASA Astrophysics Data System (ADS)
Hartnett, H. E.
2011-12-01
Many undergraduates express strong interests in research and in interdisciplinary sciences and yet, when it comes down to learning interdisciplinary material they are either unprepared for or overwhelmed by the complex interactions and relationships inherent in studying biogeochemical systems. My NSF-CAREER project "Transformation and transport of Organic Carbon in the Colorado River-Reservoir System" (EAR #0846188) combines field research with state-of-the-art analytical techniques to explore the source, fate and transport of terrestrial and riverine organic carbon in a heavily managed river system. In an effort to get undergraduates involved in research where they can really get their feet wet, I have been engaging undergraduates in a variety of field research projects that examine carbon biogeochemistry in the Colorado River watershed. The goal is to provide opportunities for students in Chemistry and in the Earth Sciences to directly experience the complexity of an environmental system, and to begin to ask manageable research questions that can be answered through field and lab work. These students are involved either as undergraduate research assistants, or as participants in my Field Geochemistry course which is offered through both the Dept. of Chemistry and the School of Earth and Space Exploration. There have been some unexpected challenges to getting these field-research projects started, but students are now successfully developing independent questions related to the larger scientific goals of the project and executing experimental and analytical research projects. To date, the PI has mentored 6 undergraduates and 2 graduate students as part of this project.
NASA Astrophysics Data System (ADS)
Adhikary, B.; Kulkarni, S.; Carmichael, G. R.; Tang, Y.; Dallura, A.; Mena, M.; Streets, D.; Zhang, Q.
2007-12-01
The Intercontinental Chemical Transport Experiment-Phase B (INTEX-B) was conducted over the Pacific Ocean during the 2006 North American spring season. One of the scientific objectives of the INTEX-B field campaign was to quantify the transport and chemical evolution/aging of Asian air pollution into North America. The field campaign deployed multiple experimental platforms such as satellites, aircrafts and surface measurements stations to study the pollution outflow to North America. Three dimensional chemical transport models were used to provide chemical weather forecasts and assist in flight planning during the mission. The Sulfur Transport and dEposition Model (STEM) is a regional chemical transport model developed at the University of Iowa. The STEM model was involved in providing chemical weather forecasts and assist in flight planning during the INTEX-B intensive field campaign. In this study we will report the STEM model performance of aerosols and trace gases in its ability to capture the pollutant plume with experimental observations obtained from the field campaign. The study will then relate the emissions of trace gases and aerosols to atmospheric composition, sources and sinks using the newly developed emissions inventory for the INTEX-B field campaign.
Daniels, Bryan A; Baldridge, William H
2011-03-01
Horizontal cells of the vertebrate retina have large receptive fields as a result of extensive gap junction coupling. Increased ambient illumination reduces horizontal cell receptive field size. Using the isolated goldfish retina, we have assessed the contribution of nitric oxide to the light-dependent reduction of horizontal cell receptive field size. Horizontal cell receptive field size was assessed by comparing the responses to centered spot and annulus stimuli and from the responses to translated slit stimuli. A period of steady illumination decreased the receptive field size of horizontal cells, as did treatment with the nitric oxide donor (Z)-1-[N-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (100 μM). Blocking the endogenous production of nitric oxide with the nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester (1 mM), decreased the light-induced reduction of horizontal cell receptive field size. These findings suggest that nitric oxide is involved in light-induced reduction of horizontal cell receptive field size. Copyright © Cambridge University Press, 2011
Stevens, Katie; Bernal, Cathy; Devis, Kate; Southgate, Andrew
2017-11-01
The aim of this study was to gain insight into service users' experiences of participating in recruitment for Adult, Mental Health and Child nursing studies at the authors' university; to establish potential motivations behind such participation; and to make suggestions for improved future practice. The involvement of service users in nurse education and recruitment has for some years been required by the Nursing and Midwifery Council, but there is a dearth of publications on the meaning of that involvement to participating service users. It is hoped that this study will contribute to this body of knowledge. A phenomenological approach was selected, field-specific focus groups of service users being facilitated using a semi-structured interview format; these were audio recorded and transcribed. The data was analysed using thematic analysis. Participation was subject to the service users having been involved in recruitment to nursing studies at the authors' university and the focus groups took place either at the university or at the child participants' school. Themes identified demonstrated largely positive experiences and a sense of meaningful involvement for all concerned. Findings indicated a close link between the values of the participants and those of the wider NHS, benefits to a sense of wellbeing and achievement, as well as the need for greater ownership of the recruitment process by service users. Potential lessons for academics wishing to promote greater service user involvement in student recruitment are articulated. Copyright © 2017 Elsevier Ltd. All rights reserved.
Jivraj, Jamil; Sacrey, Lori-Ann; Newton, Amanda; Nicholas, David; Zwaigenbaum, Lonnie
2014-10-01
Participatory research aims to increase the relevance and broaden the implementation of health research by involving those affected by the outcomes of health studies. Few studies within the field of neurodevelopmental disorders, particularly autism spectrum disorders, have involved autistic individuals as partners. This study sought to identify and characterize published participatory research partnerships between researchers and individuals with autism spectrum disorder or other neurodevelopmental disorders and examine the influence of participatory research partnerships on the research process and reported study outcomes. A search of databases and review of gray literature identified seven studies that described participatory research partnerships between academic researchers and individuals with autism spectrum disorder or other neurodevelopmental disorders. A comparative analysis of the studies revealed two key themes: (1) variations in the participatory research design and (2) limitations during the reporting of the depth of the partner's involvement. Both themes potentially limit the application and generalizability of the findings. The results of the review are discussed in relation to the use of evaluative frameworks for such participatory research studies to determine the potential benefits of participatory research partnerships within the neurodevelopmental and autism spectrum disorder populations. © The Author(s) 2014.
ERIC Educational Resources Information Center
McCulloch, Gary
2010-01-01
Brian Simon's "Studies in the History of Education", 1780-1870, published in 1960, set out to counter nearly all work previously produced on the history of education in Britain in this period, and to direct the field towards a new course. It provided a Marxist perspective that drew upon Simon's involvement in campaigns for educational…
ERIC Educational Resources Information Center
Hsiao, Hsi-Chi; Cheng, Yung-Shin
2006-01-01
This paper applies the concept of ideology to the field of design education. Specifically, this study explores the potential impact of ideology on the interaction between tutors and students involved in the education of industrial design in Taiwan. Particular emphasis is placed upon the instruction of the core curriculum. The present investigation…
NASA Technical Reports Server (NTRS)
Lyon, R. J. P.
1971-01-01
Infrared radiance measurements from geological materials were studied. These involved laboratory and field spectroscopic measurements, both on the ground and airborne. A proven, feasible system is presented for airborne use over terrains with minimal vegetation. It has been shown that the spectral emittance concepts can be utilized in emittance ratio imagery which depicts the silicate composition of the terrain.
ERIC Educational Resources Information Center
Jonas, Peter M.; Weimer, Don
This two-year study involving five colleges and universities compared the academic achievement, as measured by the Educational Testing Service (ETS) Major Field Achievement Test (MFAT) in Business of students in traditional undergraduate programs and those in non-traditional accelerated adult degree programs. The study also compared the subjects'…
ERIC Educational Resources Information Center
Hu, Hsueh-chao Marcella; Nassaji, Hossein
2012-01-01
In recent years the study of second language (L2) vocabulary learning through reading has attracted much attention in the field of L2 acquisition. A specific area that has received wide interest is the examination of the processes involved in deriving word meanings from context. The purpose of the present study was to examine the relationships…
Sixteenth International Conference on the physics of electronic and atomic collisions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dalgarno, A.; Freund, R.S.; Lubell, M.S.
1989-01-01
This report contains abstracts of papers on the following topics: photons, electron-atom collisions; electron-molecule collisions; electron-ion collisions; collisions involving exotic species; ion- atom collisions, ion-molecule or atom-molecule collisions; atom-atom collisions; ion-ion collisions; collisions involving rydberg atoms; field assisted collisions; collisions involving clusters and collisions involving condensed matter.
Pharmaceutical intervention for myopia control
Ganesan, Prema; Wildsoet, Christine F
2010-01-01
Myopia is the result of a mismatch between the optical power and the length of the eye, with the latter being too long. Driving the research in this field is the need to develop myopia treatments that can limit axial elongation. When axial elongation is excessive, as in high myopia, there is an increased risk of visual impairment and blindness due to ensuing pathologies such as retinal detachments. This article covers both clinical studies involving myopic children, and studies involving animal models for myopia. Atropine, a nonselective muscarinic antagonist, has been studied most extensively in both contexts. Because it remains the only drug used in a clinical setting, it is a major focus of the first part of this article, which also covers the many shortcomings of topical ophthalmic atropine. The second part of this article focuses on in vitro and animal-based drug studies, which encompass a range of drug targets including the retina, retinal pigment epithelium and sclera. While the latter studies have contributed to a better understanding of how eye growth is regulated, no new antimyopia drug treatments have reached the clinical setting. Less conservative approaches in research, and in particular, the exploration of new bioengineering approaches for drug delivery, are needed to advance this field. PMID:21258611
Guo, Yunsheng; Li, Jiansheng; Hou, Xiaojuan; Lv, Xiaolong; Liang, Hao; Zhou, Ji; Wu, Hongya
2017-04-07
Wireless power transfer is a nonradiative type of transmission that is performed in the near-field region. In this region, the electromagnetic fields that are produced by both the transmitting and receiving coils are evanescent fields, which should not transmit energy. This then raises the question of how the energy can be transferred. Here we describe a theoretical study of the two evanescent field distributions at different terminal loads. It is shown that the essential principle of wireless energy transfer is the superposition of the two evanescent fields, and the resulting superimposed field is mediated through the terminal load. If the terminal load is either capacitive or inductive, then the superimposed field cannot transfer the energy because its Poynting vector is zero; in contrast, if the load is resistive, energy can then be conveyed from the transmitting coil to the receiving coil. The simulation results for the magnetic field distributions and the time-domain current waveforms agree very well with the results of the theoretical analysis. This work thus provides a comprehensive understanding of the energy transfer mechanism involved in the magnetic resonant coupling system.
In vitro effects of direct current electric fields on adipose-derived stromal cells.
Hammerick, Kyle E; Longaker, Michael T; Prinz, Fritz B
2010-06-18
Endogenous electric fields play an important role in embryogenesis, regeneration, and wound repair and previous studies have shown that many populations of cells, leukocytes, fibroblasts, epithelial cells, and endothelial cells, exhibit directed migration in response to electric fields. As regenerative therapies continue to explore ways to control mesenchymal progenitor cells to recreate desirable tissues, it is increasingly necessary to characterize the vast nature of biological responses imposed by physical phenomena. Murine adipose-derived stromal cells (mASCs) migrated toward the cathode in direct current (DC) fields of physiologic strength and show a dose dependence of migration rate to stronger fields. Electric fields also caused mASCs to orient perpendicularly to the field vector and elicited a transient increase in cytosolic calcium. Additionally, their galvanotactic response appears to share classic chemotactic signaling pathways that are involved in the migration of other cell types. Galvanotaxis is one predominant result of electric fields on mASCs and it may be exploited to engineer adult stem cell concentrations and locations within implanted grafts or toward sites of wound repair. Copyright (c) 2010 Elsevier Inc. All rights reserved.
Non-equilibrium phase transitions in a driven-dissipative system of interacting bosons
NASA Astrophysics Data System (ADS)
Young, Jeremy T.; Foss-Feig, Michael; Gorshkov, Alexey V.; Maghrebi, Mohammad F.
2017-04-01
Atomic, molecular, and optical systems provide unique opportunities to study simple models of driven-dissipative many-body quantum systems. Typically, one is interested in the resultant steady state, but the non-equilibrium nature of the physics involved presents several problems in understanding its behavior theoretically. Recently, it has been shown that in many of these models, it is possible to map the steady-state phase transitions onto classical equilibrium phase transitions. In the language of Keldysh field theory, this relation typically only becomes apparent after integrating out massive fields near the critical point, leaving behind a single massless field undergoing near-equilibrium dynamics. In this talk, we study a driven-dissipative XXZ bosonic model and discover critical points at which two fields become gapless. Each critical point separates three different possible phases: a uniform phase, an anti-ferromagnetic phase, and a limit cycle phase. Furthermore, a description in terms of an equilibrium phase transition does not seem possible, so the associated phase transitions appear to be inherently non-equilibrium.
Dubé, Karine; Sylla, Laurie; Dee, Lynda
2018-02-01
We respond to Eyal et al.'s commentary focusing on how people living with HIV participating in HIV cure-related studies are defined. We argue that the types of participants enrolled in research cannot be dissociated from the study interventions, the types of anticipated risks, and the background standard of care. As the field of HIV cure research advances, more nuance and granularity will be needed to define research criteria and acceptable risk/benefit ratios for cure study participants, as well as specific tiered protocol designs that serve to protect various participant populations from untoward risks, especially in very early phase research with interventions known to have potentially serious toxicities. We highlight key lessons from the ACTIVATE study involving a latency-reversing agent, Panobinostat, for HIV cure study design involving "otherwise healthy volunteers".
Empirical studies of design software: Implications for software engineering environments
NASA Technical Reports Server (NTRS)
Krasner, Herb
1988-01-01
The empirical studies team of MCC's Design Process Group conducted three studies in 1986-87 in order to gather data on professionals designing software systems in a range of situations. The first study (the Lift Experiment) used thinking aloud protocols in a controlled laboratory setting to study the cognitive processes of individual designers. The second study (the Object Server Project) involved the observation, videotaping, and data collection of a design team of a medium-sized development project over several months in order to study team dynamics. The third study (the Field Study) involved interviews with the personnel from 19 large development projects in the MCC shareholders in order to study how the process of design is affected by organizationl and project behavior. The focus of this report will be on key observations of design process (at several levels) and their implications for the design of environments.
ERIC Educational Resources Information Center
Mercer-Mapstone, Lucy; Kuchel, Louise
2017-01-01
Science communication is a diverse and transdisciplinary field and is taught most effectively when the skills involved are tailored to specific educational contexts. Few academic resources exist to guide the teaching of communication with non-scientific audiences for an undergraduate science context. This mixed methods study aimed to explore what…
Macroinvertebrate colonization dynamics on artificial substrates along an algal resource gradient
A. Braccia; S.L. Eggert; N. King
2014-01-01
Riparian canopy removal and land use may introduce multiple stressors that can alter food and habitat for stream organisms, but the influence of these alterations on macroinvertebrate colonization dynamics is less well known. A field study involving the simultaneous placement and removal of artificial substrates was performed to examine how macroinvertebrate...
Effects of Reading Picture Books on Kindergartners' Mathematics Performance
ERIC Educational Resources Information Center
van den Heuvel-Panhuizen, Marja; Elia, Iliada; Robitzsch, Alexander
2016-01-01
This article describes a field experiment with a pretest-posttest control group design which investigated the potential of reading picture books to children for supporting their mathematical understanding. The study involved 384 children from 18 kindergarten classes in 18 schools in the Netherlands. During three months, the children in the nine…
ERIC Educational Resources Information Center
Abbott, J. Anthony
2006-01-01
Students frequently struggle when scientific instruction seems divorced from personal experience, especially in the physical sub-disciplines, like climatology, where exercise books often present historical or abstracted case studies. In contrast I present a three-phase project involving student input on experimental design, data collection, and…
Enquiry-Based Learning and Formative Assessment Environments: Student Perspectives
ERIC Educational Resources Information Center
Sambell, Kay
2010-01-01
This paper outlines case study research into first-year students' experiences of enquiry-based learning (EBL) on a year-long introductory theory module. Students were supported to carry out a series of authentic small-scale enquiries involving: (1) working in research teams; (2) gathering, disseminating and analysing data from the field; (3)…
Butterflies & Wild Bees: Biology Teachers' PCK Development through Citizen Science
ERIC Educational Resources Information Center
Scheuch, Martin; Panhuber, Tanja; Winter, Silvia; Kelemen-Finan, Julia; Bardy-Durchhalter, Manfred; Kapelari, Suzanne
2018-01-01
Citizen science is a rapidly growing emerging field in science and it is gaining importance in education. Therefore, this study was conducted to document the pedagogical content knowledge (PCK) of biology teachers who participated in a citizen science project involving observation of wild bees and identification of butterflies. In this paper,…
ERIC Educational Resources Information Center
Tobin, R. G.
2018-01-01
Abundant research leaves little question that pedagogical approaches involving active student engagement with the material, and opportunities for student-to-student discussions, lead to much better learning outcomes than traditional instructor-led, expository instructional formats, in physics and in many other fields. In introductory college…
Group vs. Individual Bystander Response to a Violent Assault: A Field Experiment.
ERIC Educational Resources Information Center
Harari, Herbert; And Others
Research studies on group versus individual bystander responses either have involved nonviolent emergencies or laboratory simulations. To investigate group versus individual bystander response to a violent assualt in a natural setting, 80 male college students (from an original pool of 393 white, male students) were observed either individually or…
ERIC Educational Resources Information Center
Wood, Marcy B.; Turner, Erin E.
2015-01-01
Studies of mathematics teacher preparation frequently lament the divide between the more theoretically based university methods course and the practically grounded classroom field experience. In many instances, attempts to mediate this gap involve creating hybrid or third spaces, which seek to dissipate the differences in knowledge status as…
Birds: A Study Guide for the Fourth Grade. Alaska Sea Week Curriculum Series. Draft.
ERIC Educational Resources Information Center
King, James G.; King, Mary Lou
Southeast Alaska's birds and wetlands are the subject of this elementary school teacher's guide and student workbook. Included are classroom activities and field investigations which address: (1) bird identification, habitats, adaptation, and conservation; and (2) the inhabitants, ecology and value of estuaries. Workbook activities involve the…
The Custody Evaluation Handbook: Research-Based Solutions and Applications.
ERIC Educational Resources Information Center
Bricklin, Barry
Three of the most challenging problems in the custody evaluation field follow from: (1) the difficulties involved in adapting data derived from group studies or traditional tests into a form for individual cases; (2) the absence of clear and compelling guidelines to aggregate the information collected in a comprehensive evaluation; and (3) the…
Understanding Student Use of Differentials in Physics Integration Problems
ERIC Educational Resources Information Center
Hu, Dehui; Rebello, N. Sanjay
2013-01-01
This study focuses on students' use of the mathematical concept of differentials in physics problem solving. For instance, in electrostatics, students need to set up an integral to find the electric field due to a charged bar, an activity that involves the application of mathematical differentials (e.g., "dr," "dq"). In this…
Cell Biology and Microbiology: A Continuous Cross-Feeding.
Pizarro-Cerdá, Javier; Cossart, Pascale
2016-07-01
Microbiology and cell biology both involve the study of cells, albeit at different levels of complexity and scale. Interactions between both fields during the past 25 years have led to major conceptual and technological advances that have reshaped the whole biology landscape and its biomedical applications. Copyright © 2016 Elsevier Ltd. All rights reserved.
ERIC Educational Resources Information Center
Mulligan, Gregory; Taylor, Nichole; Glen, Mary; Tomlin, Dona; Gaul, Catherine A.
2011-01-01
Cross-disciplinary (CD) learning experiences benefit student understanding of concepts and curriculum by offering opportunities to explore topics from the perspectives of alternate fields of study. This report involves a qualitative evaluation of CD health sciences undergraduate laboratory experiences in which concepts and students from two…
Young People Who Have Sexually Abused: What Do They (and Their Parents) Want from Professionals?
ERIC Educational Resources Information Center
Hackett, Simon; Masson, Helen
2006-01-01
This article presents the findings of a small scale qualitative study of user perspectives in the adolescent sexual aggression field. Twenty four service users who had received intervention from nine different specialist providers completed a structured questionnaire about their experiences of professional involvement. Both young people who had…
Perspectives of Parents of Children Who Are Visually Impaired: Implications for the Field.
ERIC Educational Resources Information Center
Leyser, Yona; Hienze, Toni
2001-01-01
A study involving 130 parents of children with visual impairments found parents were generally supportive of mainstreaming, but many also identified a number of risks and problems with it. Their child's social isolation concerned parents, along with the general education teacher's lack of knowledge and experience with visual impairments. (Contains…
Faculty Perceptions of Students in Life and Physical Science Research Labs
ERIC Educational Resources Information Center
Gonyo, Claire P.; Cantwell, Brendan
2015-01-01
This qualitative study involved interviews of 32 faculty principle investigators at three research institutions and explored how they view the role of students within physical and life science labs. We used socialization theory and student engagement literature to analyze faculty views, which can contribute to student investment in STEM fields.…
An Empirical Analysis of Factors Affecting Honors Program Completion Rates
ERIC Educational Resources Information Center
Savage, Hallie; Raehsler, Rod D.; Fiedor, Joseph
2014-01-01
One of the most important issues in any educational environment is identifying factors that promote academic success. A plethora of research on such factors exists across most academic fields, involving a wide range of student demographics, and the definition of student success varies across the range of studies published. The analysis in this…
Expressive Writing: Enhancing the Emotional Intelligence of Human Services Majors
ERIC Educational Resources Information Center
Castillo, Yuleinys; Fischer, Jerome M.
2017-01-01
The skills and tasks in the human services field are highly connected to emotional intelligence abilities. The purpose of the study was to investigate the effect of an expressive writing program involving human service students in an undergraduate rehabilitation services course. The program was developed to enhance their emotional intelligence.…
Lakota Undergraduates as Partners in Aging Research in American Indian Communities
ERIC Educational Resources Information Center
Anagnopoulos, Cheryl
2006-01-01
Studies have established the beneficial role of engaging students in research at both the graduate and undergraduate level. Authentic research experiences serve as a tool for instruction where students are actively involved in the process of discovery, the scientific method, and advancing existing fields with scientific data. Further, students…
Using CBPR Methods in College Health Research: Exploring Excessive Alcohol Consumption
ERIC Educational Resources Information Center
Bulmer, Sandra M.; Barton, Barbara A.; Liefeld, Julie; Montauti, Sara; Santos, Stephanie; Richard, Melissa; Hnath, Laura; Pelletier, Kara; Lalanne, Jude
2016-01-01
Community-based participatory research (CBPR) is a collaborative methodology that uniquely involves stakeholders in all stages of the research process. CBPR has been widely utilized in the field of public health, but not widely employed with college populations. This study utilized CBPR methods within a college community to gain insight into…
A Critical Review: Connecting Nature of Science and Argumentation
ERIC Educational Resources Information Center
Soysal, Y.
2015-01-01
The purpose of this critical review is to examine studies incorporating interconnectedness between Nature of Science (NOS) and Argumentation. This in-depth critical review seeks to illuminate insights and direction of the linkage between these two eminent research fields in science education. It involves a computerized, web-based search to provide…
Detention Home Teens as Tutors: A Cooperative Cross-Age Tutoring Pilot Project
ERIC Educational Resources Information Center
Lazerson, David B.
2005-01-01
Concerned professionals in the juvenile justice field frequently express concern for effective programs that help youth offenders successfully rejoin society. This mixed-method pilot study involved detention home teens functioning as tutors for special education students in a public school. Tutors were selected who, based on previous assessment as…
The Sylvia Plath Effect: Mental Illness in Eminent Creative Writers.
ERIC Educational Resources Information Center
Kaufman, James C.
2001-01-01
Two studies involving a total of 2149 writers and other eminent individuals found that female poets were significantly more likely to suffer from mental illness than female fiction writers, than male writers of any type, or than eminent individuals in other fields. This finding has been dubbed the "Sylvia Plath" effect. (Contains…
Physical Activity Measurement Instruments for Children with Cerebral Palsy: A Systematic Review
ERIC Educational Resources Information Center
Capio, Catherine M.; Sit, Cindy H. P.; Abernethy, Bruce; Rotor, Esmerita R.
2010-01-01
Aim: This paper is a systematic review of physical activity measurement instruments for field-based studies involving children with cerebral palsy (CP). Method: Database searches using PubMed Central, MEDLINE, CINAHL Plus, PsycINFO, EMBASE, Cochrane Library, and PEDro located 12 research papers, identifying seven instruments that met the inclusion…
ERIC Educational Resources Information Center
Pogorelova, Elena V.; Yakhneeva, Irina V.; Agafonova, Anna N.; Prokubovskaya, Alla O.
2016-01-01
The relevance of the analyzed issue is caused by the need to study the process of transformation of marketing in e-commerce, as the active involvement of business organizations in the field of e-business is often accompanied by problems of applying the usual marketing tools in a virtual environment. The article seeks to identify changes in the…
Parents Are Community Workers Too!
ERIC Educational Resources Information Center
Mundell, Scott
The field tested instructional unit is designed around the premise that one of the best places for students exploring the "world of work" is in their own homes with their own parents. Activities involving language arts, social studies, listening skills, speaking skills, and art are included. The unit takes approximately 10 hours teaching time and…
Student Career Preferences: In Support of a New Learning Paradigm
ERIC Educational Resources Information Center
Atamian, Rubik; Mansouri, Hossein
2013-01-01
According to the Bureau of Labor Statistics, throughout their careers, college graduates change multiple jobs and several careers, often remotely related to one another or to their major field of study. Experts project that the majority of newly created jobs requiring college education would involve extensive and prolonged on-the-job training of…
Philosophy of...Philosophy and...: Taking the Conditions We Find Ourselves in Seriously
ERIC Educational Resources Information Center
Smeyers, Paul
2011-01-01
Starting from Peters' characterization of philosophy of education, the article elaborates the development offered by the Blackwell Guide (i.e. a field of study that involves a variety of approaches, including philosophical analysis with problems rooted in the use of language in educational discourse, addressing the assumptions and values embedded…
Connecting to the Community: A Model for Caregiver-Teacher Conference Instruction
ERIC Educational Resources Information Center
Maher, Michael J.; Reiman, Alan J.
2009-01-01
Professionals throughout the field of education agree on the importance of teacher-caregiver communication. Yet teacher education programs still do very little to prepare future teachers for these interactions. This exploratory study investigated the use of a standardized caregiver model, with 12 teacher education students involved in a simulated…
Using models to provide a virtual test of forest treatments
Janet Sullivan; Kevin Hyde
2007-01-01
BEMRP's participation in the Bitterroot National Forest's proposed Trapper Bunkhouse Land Stewardship Project (Trapper-Bunkhouse Project) consists of two parts. One is the field study mentioned elsewhere in this ECO-Report that is looking into the effects of thinning and burning on various resources. The other part involves modeling to determine where...
ERIC Educational Resources Information Center
Clark, Aaron C.; Scales, Alice Y.
2000-01-01
Investigates characteristics of a quality program in graphic communications teacher education with involvement of professionals in the field. Uses the Delphi technique to achieve consensus on the characteristics that they felt compromised a good educational program for future graphics teachers. (Contains 27 references.) (Author/YDS)
ERIC Educational Resources Information Center
Hodgkins, Andrew P.
2016-01-01
This article examines a vocational education and training partnership occurring in the Canadian oil sands mining industry. The case study involves a corporate-sponsored pre-apprenticeship training programme designed to procure aboriginal labour in the province of Alberta. Interviews with members of key partner groups and stakeholders occurred…
A More Powerful Test in Three-Level Cluster Randomized Designs
ERIC Educational Resources Information Center
Konstantopoulos, Spyros
2011-01-01
Field experiments that involve nested structures frequently assign treatment conditions to entire groups (such as schools). A key aspect of the design of such experiments includes knowledge of the clustering effects that are often expressed via intraclass correlation. This study provides methods for constructing a more powerful test for the…
Marangoni-driven chemotaxis, chemotactic collapse, and the Keller-Segel equation
NASA Astrophysics Data System (ADS)
Shelley, Michael; Masoud, Hassan
2013-11-01
Almost by definition, chemotaxis involves the biased motion of motile particles along gradients of a chemical concentration field. Perhaps the most famous model for collective chemotaxis in mathematical biology is the Keller-Segel model, conceived to describe collective aggregation of slime mold colonies in response to an intrinsically produced, and diffusing, chemo-attractant. Heavily studied, particularly in 2D where the system is ``super-critical'', it has been proved that the KS model can develop finite-time singularities - so-called chemotactic collapse - of delta-function type. Here, we study the collective dynamics of immotile particles bound to a 2D interface above a 3D fluid. These particles are chemically active and produce a diffusing field that creates surface-tension gradients along the surface. The resultant Marangoni stresses create flows that carry the particles, possibly concentrating them. Remarkably, we show that this system involving 3D diffusion and fluid dynamics, exactly yields the 2D Keller-Segel model for the surface-flow of active particles. We discuss the consequences of collapse on the 3D fluid dynamics, and generalizations of the fluid-dynamical model.
Neuroimaging of the Periaqueductal Gray: State of the Field
Linnman, Clas; Moulton, Eric A.; Barmettler, Gabi; Becerra, Lino; Borsook, David
2011-01-01
This review and meta-analysis aims at summarizing and integrating the human neuroimaging studies that report periaqueductal gray (PAG) involvement; 250 original manuscripts on human neuroimaging of the PAG were identified. A narrative review and meta-analysis using activation likelihood estimates is included. Behaviors covered include pain and pain modulation, anxiety, bladder and bowel function and autonomic regulation. Methods include structural and functional magnetic resonance imaging, functional connectivity measures, diffusion weighted imaging and positron emission tomography. Human neuroimaging studies in healthy and clinical populations largely confirm the animal literature indicating that the PAG is involved in homeostatic regulation of salient functions such as pain, anxiety and autonomic function. Methodological concerns in the current literature, including resolution constraints, imaging artifacts and imprecise neuroanatomical labeling are discussed, and future directions are proposed. A general conclusion is that PAG neuroimaging is a field with enormous potential to translate animal data onto human behaviors, but with some growing pains that can and need to be addressed in order to add to our understanding of the neurobiology of this key region. PMID:22197740
NASA Astrophysics Data System (ADS)
Ma, T.-Z.; Schunk, R. W.
1994-07-01
Experiments involving the interaction of spherical conducting objects biases with hight voltages in the Low-Earth-Orbit (LEO) environment have been conducted and designed. In these experiments, both positive and negative voltages have been applied to the spheres. Previously, there have been theoretical and numerical studies of positive voltage spheres in plasmas with and without magnetic fields. There also have been studies of negative voltage objects in unmagnetized plasmas. Here, we used a fluid model to study the plasma response to a negative voltage sphere immersed in a magnetized plasma. Our main purpose was to investigate the role of the magnetic field during the early-time interaction between the negative voltage sphere and the ambient plasma in the LEO environment. In this study, different applied voltages, magnetic field strengths, and rise-times of the applied voltages were considered. It was found that with the strength of the geomagnetic field the ions are basically not affected by the magnetic field on the time scale of hundreds of plasma periods considered in this study. The ion density distribution around the sphere and the collected ion flux by the sphere are basically the same as in the case without the magnetic field. The electron motion is strongly affected by the magnetic field. One effect is to change the nature of the electron over-shoot oscillation from regular to somewhat turbulent. Although the electrons move along the magnetic field much more easily than across the magnetic field, some redirection effect causes the electron density to distribute as if the magnetic field effect is minimal. The sheath struture and the electric field around the sphere tend to be spherical. A finite rise-time of the applied voltage reduces the oscillatory activities and delays the ion acceleration. However, the effect of the rise-time depends on both the duration of the rise-time and the ion plasma period.
NASA Astrophysics Data System (ADS)
Teber, S.; Kotikov, A. V.
2018-04-01
The field theoretic renormalization study of reduced quantum electrodynamics (QED) is performed up to two loops. In the condensed matter context, reduced QED constitutes a very natural effective relativistic field theory describing (planar) Dirac liquids, e.g., graphene and graphenelike materials, the surface states of some topological insulators, and possibly half-filled fractional quantum Hall systems. From the field theory point of view, the model involves an effective (reduced) gauge field propagating with a fractional power of the d'Alembertian in marked contrast with usual QEDs. The use of the Bogoliubov-Parasiuk-Hepp-Zimmermann prescription allows for a simple and clear understanding of the structure of the model. In particular, in relation with the ultrarelativistic limit of graphene, we straightforwardly recover the results for both the interaction correction to the optical conductivity C*=(92 -9 π2)/(18 π ) and the anomalous dimension of the fermion field γψ(α ¯ ,ξ )=2 α ¯ (1 -3 ξ )/3 -16 (ζ2NF+4 /27 ) α¯ 2+O (α¯ 3) , where α ¯=e2/(4 π )2 and ξ is the gauge-fixing parameter.
Geoscience and a Lunar Base: A Comprehensive Plan for Lunar Exploration
NASA Technical Reports Server (NTRS)
Taylor, G. Jeffrey (Editor); Spudis, Paul D. (Editor)
1990-01-01
This document represents the proceedings of the Workshop on Geoscience from a Lunar Base. It describes a comprehensive plan for the geologic exploration of the Moon. The document begins by explaining the scientific importance of studying the Moon and outlines the many unsolved problems in lunar science. Subsequent chapters detail different, complementary approaches to geologic studies: global surveys, including orbiting spacecraft such as Lunar Observer and installation of a global geophysical network; reconnaissance sample return mission, by either automated rovers or landers, or by piloted forays; detailed field studies, which involve astronauts and teleoperated robotic field geologists. The document then develops a flexible scenario for exploration and sketches the technological developments needed to carry out the exploration scenario.
Złotowski, Jakub A.; Sumioka, Hidenobu; Nishio, Shuichi; Glas, Dylan F.; Bartneck, Christoph; Ishiguro, Hiroshi
2015-01-01
The uncanny valley theory proposed by Mori has been heavily investigated in the recent years by researchers from various fields. However, the videos and images used in these studies did not permit any human interaction with the uncanny objects. Therefore, in the field of human-robot interaction it is still unclear what, if any, impact an uncanny-looking robot will have in the context of an interaction. In this paper we describe an exploratory empirical study using a live interaction paradigm that involved repeated interactions with robots that differed in embodiment and their attitude toward a human. We found that both investigated components of the uncanniness (likeability and eeriness) can be affected by an interaction with a robot. Likeability of a robot was mainly affected by its attitude and this effect was especially prominent for a machine-like robot. On the other hand, merely repeating interactions was sufficient to reduce eeriness irrespective of a robot's embodiment. As a result we urge other researchers to investigate Mori's theory in studies that involve actual human-robot interaction in order to fully understand the changing nature of this phenomenon. PMID:26175702
Złotowski, Jakub A; Sumioka, Hidenobu; Nishio, Shuichi; Glas, Dylan F; Bartneck, Christoph; Ishiguro, Hiroshi
2015-01-01
The uncanny valley theory proposed by Mori has been heavily investigated in the recent years by researchers from various fields. However, the videos and images used in these studies did not permit any human interaction with the uncanny objects. Therefore, in the field of human-robot interaction it is still unclear what, if any, impact an uncanny-looking robot will have in the context of an interaction. In this paper we describe an exploratory empirical study using a live interaction paradigm that involved repeated interactions with robots that differed in embodiment and their attitude toward a human. We found that both investigated components of the uncanniness (likeability and eeriness) can be affected by an interaction with a robot. Likeability of a robot was mainly affected by its attitude and this effect was especially prominent for a machine-like robot. On the other hand, merely repeating interactions was sufficient to reduce eeriness irrespective of a robot's embodiment. As a result we urge other researchers to investigate Mori's theory in studies that involve actual human-robot interaction in order to fully understand the changing nature of this phenomenon.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Roach, Mack; De Silvio, Michelle; Valicenti, Richard
2006-11-01
Purpose: Radiation Therapy Oncology Group (RTOG) 9413 trial demonstrated a better progression-free survival (PFS) with whole-pelvis (WP) radiotherapy (RT) compared with prostate-only (PO) RT. This secondary analysis was undertaken to determine whether 'mini-pelvis' (MP; defined as {>=}10 x 11 cm but <11 x 11 cm) RT resulted in progression-free survival (PFS) comparable to that of WP RT. To avoid a timing bias, this analysis was limited to patients receiving neoadjuvant and concurrent hormonal therapy (N and CHT) in Arms 1 and 2 of the study. Methods and Materials: Eligible patients had a risk of lymph node (LN) involvement >15%. Neoadjuvantmore » and concurrent hormonal therapy (N and CHT) was administered 2 months before and during RT for 4 months. From April 1, 1995, to June 1, 1999, a group of 325 patients were randomized to WP RT + N and CHT and another group of 324 patients were randomized to receive PO RT + N and CHT. Patients randomized to PO RT were dichotomized by median field size (10 x 11 cm), with the larger field considered an 'MP' field and the smaller a PO field. Results: The median PFS was 5.2, 3.7, and 2.9 years for WP, MP, and PO fields, respectively (p = 0.02). The 7-year PFS was 40%, 35%, and 27% for patients treated to WP, MP, and PO fields, respectively. There was no association between field size and late Grade 3+ genitourinary toxicity but late Grade 3+ gastrointestinal RT complications correlated with increasing field size. Conclusions: This subset analysis demonstrates that RT field size has a major impact on PFS, and the findings support comprehensive nodal treatment in patients with a risk of LN involvement of >15%.« less
O’Connell, Caitlin; Ho, Leon C.; Murphy, Matthew C.; Conner, Ian P.; Wollstein, Gadi; Cham, Rakie; Chan, Kevin C.
2016-01-01
Human visual performance has been observed to exhibit superiority in localized regions of the visual field across many classes of stimuli. However, the underlying neural mechanisms remain unclear. This study aims to determine if the visual information processing in the human brain is dependent on the location of stimuli in the visual field and the corresponding neuroarchitecture using blood-oxygenation-level-dependent functional MRI (fMRI) and diffusion kurtosis MRI (DKI), respectively in 15 healthy individuals at 3 Tesla. In fMRI, visual stimulation to the lower hemifield showed stronger brain responses and larger brain activation volumes than the upper hemifield, indicative of the differential sensitivity of the human brain across the visual field. In DKI, the brain regions mapping to the lower visual field exhibited higher mean kurtosis but not fractional anisotropy or mean diffusivity when compared to the upper visual field. These results suggested the different distributions of microstructural organization across visual field brain representations. There was also a strong positive relationship between diffusion kurtosis and fMRI responses in the lower field brain representations. In summary, this study suggested the structural and functional brain involvements in the asymmetry of visual field responses in humans, and is important to the neurophysiological and psychological understanding of human visual information processing. PMID:27631541
NASA Astrophysics Data System (ADS)
Duke, M. B.; Budden, N. A.
1993-11-01
This report, which summarizes the Mars Exploration Study Workshop II, provides an overview of the status of the Mars Exploration Study, material presented at the workshop, and discussions of open items being addressed by the study team. The workshop assembled three teams of experts to discuss cost, dual-use technology, and international involvement, and to generate a working group white paper addressing these issues.
Resonance fluorescence microscopy via three-dimensional atom localization
NASA Astrophysics Data System (ADS)
Panchadhyayee, Pradipta; Dutta, Bibhas Kumar; Das, Nityananda; Mahapatra, Prasanta Kumar
2018-02-01
A scheme is proposed to realize three-dimensional (3D) atom localization in a driven two-level atomic system via resonance fluorescence. The field arrangement for the atom localization involves the application of three mutually orthogonal standing-wave fields and an additional traveling-wave coupling field. We have shown the efficacy of such field arrangement in tuning the spatially modulated resonance in all directions. Under different parametric conditions, the 3D localization patterns originate with various shapes such as sphere, sheets, disk, bowling pin, snake flute, flower vase. High-precision localization is achieved when the radiation field detuning equals twice the combined Rabi frequencies of the standing-wave fields. Application of a traveling-wave field of suitable amplitude at optimum radiation field detuning under symmetric standing-wave configuration leads to 100% detection probability even in sub-wavelength domain. Asymmetric field configuration is also taken into consideration to exhibit atom localization with appreciable precision compared to that of the symmetric case. The momentum distribution of the localized atoms is found to follow the Heisenberg uncertainty principle under the validity of Raman-Nath approximation. The proposed field configuration is suitable for application in the study of atom localization in an optical lattice arrangement.
Reactive Fluid Flow and Applications to Diagenesis, Mineral Deposits, and Crustal Rocks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rye, Danny M.; Bolton, Edward W.
2002-11-04
The objective is to initiate new: modeling of coupled fluid flow and chemical reactions of geologic environments; experimental and theoretical studies of water-rock reactions; collection and interpretation of stable isotopic and geochemical field data at many spatial scales of systems involving fluid flow and reaction in environments ranging from soils to metamorphic rocks. Theoretical modeling of coupled fluid flow and chemical reactions, involving kinetics, has been employed to understand the differences between equilibrium, steady-state, and non-steady-state behavior of the chemical evolution of open fluid-rock systems. The numerical codes developed in this project treat multi-component, finite-rate reactions combined with advective andmore » dispersive transport in multi-dimensions. The codes incorporate heat, mass, and isotopic transfer in both porous and fractured media. Experimental work has obtained the kinetic rate laws of pertinent silicate-water reactions and the rates of Sr release during chemical weathering. Ab-initio quantum mechanical techniques have been applied to obtain the kinetics and mechanisms of silicate surface reactions and isotopic exchange between water and dissolved species. Geochemical field-based studies were carried out on the Wepawaug metamorphic schist, on the Irish base-metal sediment-hosted ore system, in the Dalradian metamorphic complex in Scotland, and on weathering in the Columbia River flood basalts. The geochemical and isotopic field data, and the experimental and theoretical rate data, were used as constraints on the numerical models and to determine the length and time scales relevant to each of the field areas.« less
Redox signaling: An evolution from free radicals to aging.
Forman, Henry Jay
2016-08-01
Redox biology has evolved from studies of the pathology that involves oxidants to an understanding of how oxidants participate in normal as well as aberrant signal transduction. Although the concept that signal transduction involved changes in the redox state dates from the 1930s, the modern history of redox biology began with the discovery of superoxide dismutase by McCord and Fridovich. The initial focus was on free radicals and damage of macromolecules, which remains an important topic. But, over time it was realized that hydroperoxides, especially H2O2 produced by NADPH oxidases, and electrophiles derived from lipid peroxidation or metabolism, played essential roles in physiologically relevant signaling. The mechanisms through which H2O2 and other electrophiles signal became an important area of study that provided insight into how these reactive molecules were involved in major signaling pathways and regulation of transcription factors. Thus, the field of redox signaling that is the overlap of signal transduction with redox biology was established. Alterations in redox signaling are observed in aging, but we also now know that redox signaling is essential in physiological homeostasis and that sustained deviation from redox homeostasis results in disease. This is a review of the history of redox biology from a personal perspective of nearly fifty years working in this field that hopefully provides some insights for the reader. Copyright © 2016 Elsevier Inc. All rights reserved.
NASA Technical Reports Server (NTRS)
Sterling, Alphonse C.; Moore, Ronald L.
2007-01-01
We consider processes occurring just prior to and at the start of the onset of flare- and CME-producing solar eruptions. Our recent work uses observations of filament motions around the time of eruption onset as a proxy for the evolution of the fields involved in the eruption. Frequently the filaments show a slow rise prior to fast eruption, indicative of a slow expansion of the field that is about co explode. Work by us and others suggests that reconnection involving emerging or canceling flux results in a lengthening of fields restraining the filament-carrying field, and the consequent upward expansion of the field in and around the filament produces the filament's slow rise: that is, the reconnection weakens the magnetic "tethers" ("tether-weakening" reconnection), and results in the slow rise of the filament. It is still inconclusive, however, what mechanism is responsible for the switch from the slow rise to the fast eruption.
ERIC Educational Resources Information Center
Shearer, William M.
Written for students in the fields of speech correction and audiology, the text deals with the following: structures involved in respiration; the skeleton and the processes of inhalation and exhalation; phonation and pitch, the larynx, and esophageal speech; muscles involved in articulation; muscles involved in resonance; and the anatomy of the…
Retrieving Storm Electric Fields From Aircraft Field Mill Data. Part 2; Applications
NASA Technical Reports Server (NTRS)
Koshak, W. J.; Mach, D. M.; Christian, H. J.; Stewart, M. F.; Bateman, M. G.
2005-01-01
The Lagrange multiplier theory and "pitch down method" developed in Part I of this study are applied to complete the calibration of a Citation aircraft that is instrumented with six field mill sensors. When side constraints related to average fields are used, the method performs well in computer simulations. For mill measurement errors of 1 V/m and a 5 V/m error in the mean fair weather field function, the 3-D storm electric field is retrieved to within an error of about 12%. A side constraint that involves estimating the detailed structure of the fair weather field was also tested using computer simulations. For mill measurement errors of 1 V/m, the method retrieves the 3-D storm field to within an error of about 8% if the fair weather field estimate is typically within 1 V/m of the true fair weather field. Using this side constraint and data from fair weather field maneuvers taken on 29 June 2001, the Citation aircraft was calibrated. The resulting calibration matrix was then used to retrieve storm electric fields during a Citation flight on 2 June 2001. The storm field results are encouraging and agree favorably with the results obtained from earlier calibration analyses that were based on iterative techniques.
Natural inflation from polymer quantization
NASA Astrophysics Data System (ADS)
Ali, Masooma; Seahra, Sanjeev S.
2017-11-01
We study the polymer quantization of a homogeneous massive scalar field in the early Universe using a prescription inequivalent to those previously appearing in the literature. Specifically, we assume a Hilbert space for which the scalar field momentum is well defined but its amplitude is not. This is closer in spirit to the quantization scheme of loop quantum gravity, in which no unique configuration operator exists. We show that in the semiclassical approximation, the main effect of this polymer quantization scheme is to compactify the phase space of chaotic inflation in the field amplitude direction. This gives rise to an effective scalar potential closely resembling that of hybrid natural inflation. Unlike polymer schemes in which the scalar field amplitude is well defined, the semiclassical dynamics involves a past cosmological singularity; i.e., this approach does not mitigate the big bang.
NASA Astrophysics Data System (ADS)
Melo-Niño, Lina Viviana; Cañada, Florentina; Mellado, Vicente
2017-02-01
We explore the initial characterization of the pedagogical content knowledge of four, in-service, Colombian pre-university secondary education physics teachers on the concept of electric field. Two of them teach the content in English as a second language. The aim of the study was to obtain an image of the participants' teaching of electric field and the inherent complexities that go with that. The results revealed that factors which involved their personal educational models, such as, how they interpret their school's curriculum, the relationship they see between physics and mathematics, the most effective strategies for teaching physics, and the time they have available to develop the topic played a significant role. The teachers considered it essential to establish new strategies that would motivate the pupils by helping them visualize the electric field.
NASA Astrophysics Data System (ADS)
Tiutiunnyk, A.; Mora-Ramos, M. E.; Morales, A. L.; Duque, C. M.; Restrepo, R. L.; Ungan, F.; Martínez-Orozco, J. C.; Kasapoglu, E.; Duque, C. A.
2017-02-01
In this work we shall present a study of inelastic light scattering involving inter-subband electron transitions in coupled GaAs-(Ga,Al)As quantum wells. Calculations include the electron related Raman differential cross section and Raman gain. The effects of an external nonresonant intense laser field are used in order to tune these output properties. The confined electron states will be described by means of a diagonalization procedure within the effective mass and parabolic band approximations. It is shown that the application of the intense laser field can produce values of the intersubband electron Raman gain above 400 cm-1. The system proposed here is an alternative choice for the development of AlxGa1-xAs semiconductor laser diodes that can be tuned via an external nonresonant intense laser field.
Reactions between NO/+/ and metal atoms using magnetically confined afterglows
NASA Technical Reports Server (NTRS)
Lo, H. H.; Clendenning, L. M.; Fite, W. L.
1977-01-01
A new method of studying thermal energy ion-neutral collision processes involving nongaseous neutral atoms is described. A long magnetic field produced by a solenoid in a vacuum chamber confines a thermal-energy plasma generated by photoionization of gas at very low pressure. As the plasma moves toward the end of the field, it is crossed by a metal atom beam. Ionic products of ion-atom reactions are trapped by the field and both the reactant and product ions move to the end of the magnetic field where they are detected by a quadrupole mass filter. The cross sections for charge transfer between NO(+) and Na, Mg, Ca, and Sr and that for rearrangement between NO(+) and Ca have been obtained. The charge-transfer reaction is found strongly dominant over the rearrangement reaction that forms metallic oxide ions.