Six-Year-Olds' Learning of Novel Words through Addressed and Overheard Speech

ERIC Educational Resources Information Center

Boderé, Anneleen; Jaspaert, Koen

2017-01-01

Recent research indicates that infants can learn novel words equally well through addressed speech as through overhearing two adult experimenters. The current study examined to which extent six-year-old children learn from overhearing opportunities in regular kindergarten classroom practices. Fifty-three children (M age = 5;6) were exposed to a…

Assessing the Impact of Faculty-Led Supplemental Instruction on Attrition, GPA, and Graduation Rates

ERIC Educational Resources Information Center

Bryan, Karla Needham

2013-01-01

The purpose of this quasi-experimental, quantitative study was to investigate the effectiveness of supplemental instruction (SI) as a means to address the existing high attrition and low graduation rates evidenced at a rural southern community college. The research problem addressed the high attrition rates in barrier courses and low graduation…

Meteorological, snow, streamflow, topographic, and vegetation height data from four western juniper-dominated experimental catchments in southwestern Idaho, USA

USDA-ARS?s Scientific Manuscript database

Weather, snow, stream, topographic, and vegetation data are presented from the South Mountain Experimental Catchments. This study site was established in 2007 as a collaborative, long-term research laboratory to address the impacts of western juniper encroachment and treatments in the interior Great...

Reference Stands for Silvicultural Research: A Maine Perspective

Treesearch

Laura S. Kenefic; Alan S. White; Andrew R. Cutko; Shawn Fraver

2005-01-01

Silvicultural experiments should have untreated stand replicates in which development can be tracked over time. Unfortunately, field studies are seldom ideal. This article is one of six in this issue addressing experimental controls. Our focus is the Penobscot Experimental Forest (PEF) in Maine, where a 55-year-old experiment in northern conifer silviculture has an...

Physiological Event Prediction in Evaluations of Underwater Breathing Apparatus

DTIC Science & Technology

2016-10-25

Navy Experimental Diving Unit TA 15-02 321 Bullfinch Rd. NEDU TR 16-04 Panama City, FL 32407-7015 October 2016 Physiological...Event Prediction in Evaluations of Underwater Breathing Apparatus NAVY EXPERIMENTAL DIVING UNIT Author...5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Navy Experimental

Ecoinformatics (Big Data) for Agricultural Entomology: Pitfalls, Progress, and Promise.

PubMed

Rosenheim, Jay A; Gratton, Claudio

2017-01-31

Ecoinformatics, as defined in this review, is the use of preexisting data sets to address questions in ecology. We provide the first review of ecoinformatics methods in agricultural entomology. Ecoinformatics methods have been used to address the full range of questions studied by agricultural entomologists, enabled by the special opportunities associated with data sets, nearly all of which have been observational, that are larger and more diverse and that embrace larger spatial and temporal scales than most experimental studies do. We argue that ecoinformatics research methods and traditional, experimental research methods have strengths and weaknesses that are largely complementary. We address the important interpretational challenges associated with observational data sets, highlight common pitfalls, and propose some best practices for researchers using these methods. Ecoinformatics methods hold great promise as a vehicle for capitalizing on the explosion of data emanating from farmers, researchers, and the public, as novel sampling and sensing techniques are developed and digital data sharing becomes more widespread.

Functional Assessment and Positive Support Strategies for Promoting Resilience: Effects on Teachers and High-Risk Children

ERIC Educational Resources Information Center

Stoiber, Karen Callan; Gettinger, Maribeth

2011-01-01

The purpose of this study was to conduct an experimental analysis of teachers' use of functional assessment (FA) and positive behavior support (PBS) for addressing challenging behaviors in young children. A group of 35 experimental teachers participated in professional development designed to provide step-by-step training and guided implementation…

Unique Power Electronics and Drives Experimental Bench (PEDEB) to Facilitate Learning and Research

ERIC Educational Resources Information Center

Anand, S.; Farswan, R. S.; Fernandes, B. G.

2012-01-01

Experimentation is important for learning and research in the field of power electronics and drives. However, a great deal of equipment is required to study the various topologies, controllers, and functionalities. Thus, the cost of establishing good laboratories and research centers is high. To address this problem, the authors have developed a…

Experimental Studies in a Reconfigurable C4 Test-bed for Network Enabled Capability

DTIC Science & Technology

2006-06-01

Cross1, Dr R. Houghton1, and Mr R. McMaster1 Defence Technology Centre for Human factors Integration (DTC HFI ) BITlab, School of Engineering and Design...NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Defence Technology Centre for Human factors Integration (DTC HFI ) BITlab, School of...studies into NEC by the Human Factors Integration Defence Technology Centre ( HFI -DTC). DEVELOPMENT OF THE TESTBED In brief, the C4 test-bed

Self-addressed diffractive lens schemes for the characterization of LCoS displays

NASA Astrophysics Data System (ADS)

Zhang, Haolin; Lizana, Angel; Iemmi, Claudio; Monroy-Ramírez, Freddy A.; Marquez, Andrés.; Moreno, Ignacio; Campos, Juan

2018-02-01

We proposed a self-calibration method to calibrate both the phase-voltage look-up table and the screen phase distribution of Liquid Crystal on Silicon (LCoS) displays by implementing different lens configurations on the studied device within a same optical scheme. On the one hand, the phase-voltage relation is determined from interferometric measurements, which are obtained by addressing split-lens phase distributions on the LCoS display. On the other hand, the surface profile is retrieved by self-addressing a diffractive micro-lens array to the LCoS display, in a way that we configure a Shack-Hartmann wavefront sensor that self-determines the screen spatial variations. Moreover, both the phase-voltage response and the surface phase inhomogeneity of the LCoS are measured within the same experimental set-up, without the necessity of further adjustments. Experimental results prove the usefulness of the above-mentioned technique for LCoS displays characterization.

Proceedings of the Thirteenth NASA Propagation Experimenters Meeting (NAPEX 13)

NASA Technical Reports Server (NTRS)

Davarian, Faramaz (Editor)

1989-01-01

The NASA Propagation Experimenters Meeting (NAPEX), supported by the NASA Propagation Program, is convened annually to discuss studies made on radio wave propagation by investigators from domestic and international organizations. The meeting was organized into three technical sessions: the first focused on mobile satellite propagation; the second examined the propagation effects for frequencies above 10 GHz; and the third addressed studies devoted exclusively to the Olympus/Advanced Communications Technology Satellite (ACTS) Program.

A propagation experiment for modelling high elevation angle land mobile satellite channels

NASA Technical Reports Server (NTRS)

Richharia, M.; Evans, B. G.; Butt, G.

1990-01-01

This paper summarizes the results of a feasibility study for conducting high elevation angle propagation experiments in the European region for land mobile satellite communication. The study addresses various aspects of a proposed experiment. These include the selection of a suitable source for transmission, possibility of gathering narrow and wide band propagation data in various frequency bands, types of useful data, data acquisition technique, possible experimental configuration, and other experimental details.

Quasi-experimental study designs series-paper 9: collecting data from quasi-experimental studies.

PubMed

Aloe, Ariel M; Becker, Betsy Jane; Duvendack, Maren; Valentine, Jeffrey C; Shemilt, Ian; Waddington, Hugh

2017-09-01

To identify variables that must be coded when synthesizing primary studies that use quasi-experimental designs. All quasi-experimental (QE) designs. When designing a systematic review of QE studies, potential sources of heterogeneity-both theory-based and methodological-must be identified. We outline key components of inclusion criteria for syntheses of quasi-experimental studies. We provide recommendations for coding content-relevant and methodological variables and outlined the distinction between bivariate effect sizes and partial (i.e., adjusted) effect sizes. Designs used and controls used are viewed as of greatest importance. Potential sources of bias and confounding are also addressed. Careful consideration must be given to inclusion criteria and the coding of theoretical and methodological variables during the design phase of a synthesis of quasi-experimental studies. The success of the meta-regression analysis relies on the data available to the meta-analyst. Omission of critical moderator variables (i.e., effect modifiers) will undermine the conclusions of a meta-analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

Omani Girls' Conceptions of Gender Equality: Addressing Socially Constructed Sexist Attitudes through Educational Intervention

ERIC Educational Resources Information Center

Al Sadi, Fatma H.; Basit, Tehmina N.

2017-01-01

This paper is based on a quasi-experimental study which examines the effects of a school-based intervention on Omani girls' attitudes towards the notion of gender equality. A questionnaire was administered before and after the intervention to 241 girls (116 in the experimental group; 125 in the control group). A semi-structured interview was…

Guidance for Evaluating the Safety of Experimental Releases of Mosquitoes, Emphasizing Mark-Release-Recapture Techniques

PubMed Central

Charlwood, J. Derek; Harrington, Laura C.; Lounibos, L. Philip; Reisen, William K.; Tabachnick, Walter J.

2018-01-01

Abstract Experimental releases of mosquitoes are performed to understand characteristics of populations related to the biology, ability to transmit pathogens, and ultimately their control. In this article, we discuss considerations related to the safety of experimental releases of living mosquitoes, applying principles of good practice in vector biology that protect human health and comfort. We describe specific factors of experimental releases of mosquitoes that we believe are critical to inform institutional biosafety committees and similar review boards to which proposals to conduct mosquito release experiments have been submitted. In this study, “experimental releases” means those that do not significantly increase vector capacity or nuisance biting relative to the unperturbed natural baseline. This document specifically does not address releases of mosquitoes for ongoing control programs or trials of new control methods for which broader assessments of risk are required. It also does not address releases of transgenic or exotic (non-native) mosquito species, both of which require particular regulatory approval. Experimental releases may include females and males and evaluation must consider their effects based on the number released, their genotype and phenotype, the environment into which they are released, and postrelease collection activities. We consider whether increases of disease transmission and nuisance biting might result from proposed experimental releases against the backdrop of natural population size variation. We recommend that experimental releases be conducted in a manner that can be reasonably argued to have insignificant negative effects. Reviewers of proposals for experimental releases should expect applicants to provide such an argument based on evidence from similar studies and their planned activities. This document provides guidance for creating and evaluating such proposals. PMID:29337660

Guidance for Evaluating the Safety of Experimental Releases of Mosquitoes, Emphasizing Mark-Release-Recapture Techniques.

PubMed

Benedict, Mark Q; Charlwood, J Derek; Harrington, Laura C; Lounibos, L Philip; Reisen, William K; Tabachnick, Walter J

2018-01-01

Experimental releases of mosquitoes are performed to understand characteristics of populations related to the biology, ability to transmit pathogens, and ultimately their control. In this article, we discuss considerations related to the safety of experimental releases of living mosquitoes, applying principles of good practice in vector biology that protect human health and comfort. We describe specific factors of experimental releases of mosquitoes that we believe are critical to inform institutional biosafety committees and similar review boards to which proposals to conduct mosquito release experiments have been submitted. In this study, "experimental releases" means those that do not significantly increase vector capacity or nuisance biting relative to the unperturbed natural baseline. This document specifically does not address releases of mosquitoes for ongoing control programs or trials of new control methods for which broader assessments of risk are required. It also does not address releases of transgenic or exotic (non-native) mosquito species, both of which require particular regulatory approval. Experimental releases may include females and males and evaluation must consider their effects based on the number released, their genotype and phenotype, the environment into which they are released, and postrelease collection activities. We consider whether increases of disease transmission and nuisance biting might result from proposed experimental releases against the backdrop of natural population size variation. We recommend that experimental releases be conducted in a manner that can be reasonably argued to have insignificant negative effects. Reviewers of proposals for experimental releases should expect applicants to provide such an argument based on evidence from similar studies and their planned activities. This document provides guidance for creating and evaluating such proposals.

Interface Pattern Selection Criterion for Cellular Structures in Directional Solidification

NASA Technical Reports Server (NTRS)

Trivedi, R.; Tewari, S. N.; Kurtze, D.

1999-01-01

The aim of this investigation is to establish key scientific concepts that govern the selection of cellular and dendritic patterns during the directional solidification of alloys. We shall first address scientific concepts that are crucial in the selection of interface patterns. Next, the results of ground-based experimental studies in the Al-4.0 wt % Cu system will be described. Both experimental studies and theoretical calculations will be presented to establish the need for microgravity experiments.

A review of population data utilization in beef cattle research.

PubMed

Jones, R; Langemeier, M

2010-04-01

Controlled experimentation has been the most common source of research data in most biological sciences. However, many research questions lend themselves to the use of population data, or combinations of population data and data resulting from controlled experimentation. Studies of important economic outcomes, such as efficiency, profits, and costs, lend themselves particularly well to this type of analysis. Analytical methods that have been most commonly applied to population data in studies related to livestock production and management include statistical regression and mathematical programming. In social sciences, such as applied economics, it has become common to utilize more than one method in the same study to provide answers to the various questions at hand. Of course, care must be taken to ensure that the methods of analysis are appropriately applied; however, a wide variety of beef industry research questions are being addressed using population data. Issues related to data sources, aggregation levels, and consistency of collection often surface when using population data. These issues are addressed by careful consideration of the questions being addressed and the costs of data collection. Previous research across a variety of cattle production and marketing issues provides a broad foundation upon which to build future research. There is tremendous opportunity for increased use of population data and increased collaboration across disciplines to address issues of importance to the cattle industry.

A Study of Curriculum Effectiveness in Social Studies

ERIC Educational Resources Information Center

Little, Catherine A.; Feng, Annie Xuemei; VanTassel-Baska, Joyce; Rogers, Karen B.; Avery, Linda D.

2007-01-01

This quasi-experimental study examines the effects on student performance of a Javits-funded curriculum designed to respond to the needs of high-ability students in elementary and middle school social studies. The curriculum, implemented with all students in heterogeneous classrooms, addresses state standards while integrating advanced content,…

Neuroimaging in aphasia treatment research: Standards for establishing the effects of treatment

PubMed Central

Kiran, Swathi; Ansaldo, Ana; Bastiaanse, Roelien; Cherney, Leora R.; Howard, David; Faroqi-Shah, Yasmeen; Meinzer, Marcus; Thompson, Cynthia K

2012-01-01

The goal of this paper is to discuss experimental design options available for establishing the effects of treatment in studies that aim to examine the neural mechanisms associated with treatment-induced language recovery in aphasia, using functional magnetic resonance imaging (fMRI). We present both group and single-subject experimental or case-series design options for doing this and address advantages and disadvantages of each. We also discuss general components of and requirements for treatment research studies, including operational definitions of variables, criteria for defining behavioral change and treatment efficacy, and reliability of measurement. Important considerations that are unique to neuroimaging-based treatment research are addressed, pertaining to the relation between the selected treatment approach and anticipated changes in language processes/functions and how such changes are hypothesized to map onto the brain. PMID:23063559

MOLECULAR DYNAMICS SIMULATION AND EXPERIMENTAL STUDIES OF GOLD NANOPARTICLE TEMPLATED HDL-LIKE NANOPARTICLES FOR CHOLESTEROL (POSTPRINT)

DTIC Science & Technology

2016-12-21

STINFO COPY) AIR FORCE RESEARCH LABORATORY MATERIALS AND MANUFACTURING DIRECTORATE WRIGHT-PATTERSON AIR FORCE BASE, OH 45433-7750 AIR FORCE MATERIEL...9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING AGENCY ACRONYM(S) Air Force Research Laboratory...removing excess cholesterol from arterial plaques. Gold nanoparticles (AuNPs) functionalized with apolipoprotein A-I and with the lipids 1,2

Closing the Gap in Mammogram Screening: An Experimental Intervention among Low-Income Hispanic Women in Community Health Clinics

ERIC Educational Resources Information Center

Deavenport, Alexis; Modeste, Naomi; Marshak, Helen Hopp; Neish, Christine

2011-01-01

A low rate of mammogram screening exists among low-income Hispanic women. To address this disparity, an experimental intervention containing audiovisual and written media was conducted using the health belief model as a framework. The purpose of this study was to determine if low-income Hispanic women, more than 40 years of age, who received…

Preliminary investigation of power flow and electrode phenomena in a multi-megawatt coaxial plasma thruster

NASA Technical Reports Server (NTRS)

Schoenberg, Kurt; Gerwin, Richard; Henins, Ivars; Mayo, Robert; Scheuer, Jay; Nurden, Glen

1993-01-01

This paper summarizes preliminary experimental and theoretical research that was directed towards the study of quasisteady-state power flow in a large, un-optimized, multi-megawatt coaxial plasma thruster. The report addresses large coaxial thruster operation and includes evaluation and interpretation of the experimental results with a view to the development of efficient, steady-state megawatt-class magnetoplasmadynamic (MPD) thrusters.

Blois 5: Experimental summary

NASA Astrophysics Data System (ADS)

Albrow, M. G.

1993-09-01

The author gives a summary talk of the best experimental data given at the 5th Blois Workshop on Elastic and Diffractive Scattering. He addresses the following eight areas in his talk: total and elastic cross sections; single diffractive excitation; electron-proton scattering; di-jets and rapidity gaps; areas of future study; spins and asymmetries; high-transverse momentum and masses at the Tevatron; and disoriented chiral condensates and cosmic radiation.

Functional Utilization of DABS Data Link Discrete Address Beacon System

DOT National Transportation Integrated Search

1978-10-01

The report describes the output of a Task Force established by FAA Headquarters, SRDS, Robert Wedan, in June 1977 to study and recommend potential applications for Data Link to the DABS Experimentation Program

Space weightlessness and hormonal changes in human subjects and experimental animals

NASA Technical Reports Server (NTRS)

Grindeland, R. E.

1982-01-01

Data from spaceflight and bed rest studies are briefly described and the difficulties in interpreting these results are discussed. Growth hormone, prolactin, adrenocorticotropic hormone, cortisol, insulin, aldosterone, and other hormones are addressed.

Health Benefits of Animal Research: The Rat in Biomedical Research.

ERIC Educational Resources Information Center

Gill, Thomas J.

1985-01-01

Discusses major uses of rats as experimental animals for studying health concerns, pointing out that their size, gestation, and histocompatibility make them useful in various studies. Topic areas addressed include aging, autoimmune disease, genetics, cancer, diabetes, hypertension, infection, reproduction, and behavior. (DH)

Bayesian inference for dynamic transcriptional regulation; the Hes1 system as a case study.

PubMed

Heron, Elizabeth A; Finkenstädt, Bärbel; Rand, David A

2007-10-01

In this study, we address the problem of estimating the parameters of regulatory networks and provide the first application of Markov chain Monte Carlo (MCMC) methods to experimental data. As a case study, we consider a stochastic model of the Hes1 system expressed in terms of stochastic differential equations (SDEs) to which rigorous likelihood methods of inference can be applied. When fitting continuous-time stochastic models to discretely observed time series the lengths of the sampling intervals are important, and much of our study addresses the problem when the data are sparse. We estimate the parameters of an autoregulatory network providing results both for simulated and real experimental data from the Hes1 system. We develop an estimation algorithm using MCMC techniques which are flexible enough to allow for the imputation of latent data on a finer time scale and the presence of prior information about parameters which may be informed from other experiments as well as additional measurement error.

A new method to study ferroelectrics using the remanent Henkel plots

NASA Astrophysics Data System (ADS)

Vopson, Melvin M.

2018-05-01

Analysis of experimental curves constructed from dc demagnetization and isothermal remanent magnetization known as Henkel and delta M plots, have served for over 53 years as an important tool for characterization of interactions in ferromagnets. In this article we address the question whether the same experimental technique could be applied to the study of ferroelectric systems. The successful measurement of the equivalent dc depolarisation and isothermal remanent polarization curves and the construction of the Henkel and delta P plots for ferroelectrics is reported here. Full measurement protocol is provided together with experimental examples for two ferroelectric ceramic samples. This new measurement technique is an invaluable experimental tool that could be used to further advance our understanding of ferroelectric materials and their applications.

Sample Fabrication and Experimental Approach for Studying Interfacial Sliding in Thin Film-Substrate Systems

DTIC Science & Technology

2006-09-01

ORGANIZATION NAME(S) AND ADDRESS( ES ) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9...SPONSORING /MONITORING AGENCY NAME(S) AND ADDRESS( ES ) N/A 10. SPONSORING/MONITORING AGENCY REPORT NUMBER 11. SUPPLEMENTARY NOTES The views expressed...mounted in a SATEC load frame. Figure 4 is a schematic of the diffusion bonding chamber and associated equipment. Al/Si and Cu/Quartz samples were

Study of Residual Stresses and Distortion in Structural Weldments in High-Strength Steels.

DTIC Science & Technology

1982-11-30

02139 II. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE Department of the Navy November 30, 1982 Office of Naval Research 13. NUMBER OF PAGES...Arlington, Virginia 22217 14. MONITORING AGENCY NAME & ADDRESS(if different from Controlling Office) 15. SECURITY CLASS. (of this report) Unclassified 15a...a residual stress field were calculated. Finally, results from all of the afLrementioned analyses were compared with data obtained from experimental

Experimental design and quantitative analysis of microbial community multiomics.

PubMed

Mallick, Himel; Ma, Siyuan; Franzosa, Eric A; Vatanen, Tommi; Morgan, Xochitl C; Huttenhower, Curtis

2017-11-30

Studies of the microbiome have become increasingly sophisticated, and multiple sequence-based, molecular methods as well as culture-based methods exist for population-scale microbiome profiles. To link the resulting host and microbial data types to human health, several experimental design considerations, data analysis challenges, and statistical epidemiological approaches must be addressed. Here, we survey current best practices for experimental design in microbiome molecular epidemiology, including technologies for generating, analyzing, and integrating microbiome multiomics data. We highlight studies that have identified molecular bioactives that influence human health, and we suggest steps for scaling translational microbiome research to high-throughput target discovery across large populations.

A proposed reductionist solution to address the methodological challenges of inconsistent reflexology maps and poor experimental controls in reflexology research: a discussion paper.

PubMed

Jones, Jenny; Thomson, Patricia; Lauder, William; Leslie, Stephen J

2013-03-01

Reflexology is a complex massage intervention, based on the concept that specific areas of the feet (reflex points) correspond to individual internal organs within the body. Reflexologists trained in the popular Ingham reflexology method claim that massage to these points, using massage techniques unique to reflexology, stimulates an increase in blood supply to the corresponding organ. Reflexology researchers face two key methodological challenges that need to be addressed if a specific treatment-related hemodynamic effect is to be scientifically demonstrated. The first is the problem of inconsistent reflexology foot maps; the second is the issue of poor experimental controls. This article proposes a potential experimental solution that we believe can address both methodological challenges and in doing so, allow any specific hemodynamic treatment effect unique to reflexology to experimentally reveal itself.

Extending the ARS Experimental Watersheds to Address Regional Issues

NASA Astrophysics Data System (ADS)

Marks, D.; Goodrich, D. C.; Winstral, A.; Bosch, D. D.; Pool, D.

2001-12-01

The USDA-Agricultural Research Service's (ARS) Watershed Research Program maintains and operates a diverse, geog raphically distributed, nested, multi-scale, national ex perimental watershed network. This network, much of which has been operational for more than 40 years (several more than 60 years), constitutes one the best networks of its kind in the world. The watershed network and its instrumentation was primarily established to assess the hydrologic impacts of watershed conservation and management practices. It has evolved, through development of long-term hydrologic data, as a network of high quality outdoor laboratories for addressing emerging science issues facing hydrologists and resource managers. While the value of the experimental watershed for investigating precipitation, climatic, and hydrologic processes is unquestioned, extending the results from these investigations to other sites and larger areas is more difficult. ARS experimental watersheds are a few hundred km2 or smaller making it challenging to address regional scale issues. To address this the ARS watershed program is, with a suite of partners from universities and other federal agencies, enlarging its research focus to extend beyond the boundaries of the experimental watershed. In this poster we present several examples of this effort, with suggestions on how, using the experimental watershed and its core, a larger scale hydrologic observatory could be developed and maintained.

Issues and recent advances in optimal experimental design for site investigation (Invited)

NASA Astrophysics Data System (ADS)

Nowak, W.

2013-12-01

This presentation provides an overview over issues and recent advances in model-based experimental design for site exploration. The addressed issues and advances are (1) how to provide an adequate envelope to prior uncertainty, (2) how to define the information needs in a task-oriented manner, (3) how to measure the expected impact of a data set that it not yet available but only planned to be collected, and (4) how to perform best the optimization of the data collection plan. Among other shortcomings of the state-of-the-art, it is identified that there is a lack of demonstrator studies where exploration schemes based on expert judgment are compared to exploration schemes obtained by optimal experimental design. Such studies will be necessary do address the often voiced concern that experimental design is an academic exercise with little improvement potential over the well- trained gut feeling of field experts. When addressing this concern, a specific focus has to be given to uncertainty in model structure, parameterizations and parameter values, and to related surprises that data often bring about in field studies, but never in synthetic-data based studies. The background of this concern is that, initially, conceptual uncertainty may be so large that surprises are the rule rather than the exception. In such situations, field experts have a large body of experience in handling the surprises, and expert judgment may be good enough compared to meticulous optimization based on a model that is about to be falsified by the incoming data. In order to meet surprises accordingly and adapt to them, there needs to be a sufficient representation of conceptual uncertainty within the models used. Also, it is useless to optimize an entire design under this initial range of uncertainty. Thus, the goal setting of the optimization should include the objective to reduce conceptual uncertainty. A possible way out is to upgrade experimental design theory towards real-time interaction with the ongoing site investigation, such that surprises in the data are immediately accounted for to restrict the conceptual uncertainty and update the optimization of the plan.

The Experimental Design Assistant.

PubMed

Percie du Sert, Nathalie; Bamsey, Ian; Bate, Simon T; Berdoy, Manuel; Clark, Robin A; Cuthill, Innes; Fry, Derek; Karp, Natasha A; Macleod, Malcolm; Moon, Lawrence; Stanford, S Clare; Lings, Brian

2017-09-01

Addressing the common problems that researchers encounter when designing and analysing animal experiments will improve the reliability of in vivo research. In this article, the Experimental Design Assistant (EDA) is introduced. The EDA is a web-based tool that guides the in vivo researcher through the experimental design and analysis process, providing automated feedback on the proposed design and generating a graphical summary that aids communication with colleagues, funders, regulatory authorities, and the wider scientific community. It will have an important role in addressing causes of irreproducibility.

The Experimental Design Assistant

PubMed Central

Bamsey, Ian; Bate, Simon T.; Berdoy, Manuel; Clark, Robin A.; Cuthill, Innes; Fry, Derek; Karp, Natasha A.; Macleod, Malcolm; Moon, Lawrence; Stanford, S. Clare; Lings, Brian

2017-01-01

Addressing the common problems that researchers encounter when designing and analysing animal experiments will improve the reliability of in vivo research. In this article, the Experimental Design Assistant (EDA) is introduced. The EDA is a web-based tool that guides the in vivo researcher through the experimental design and analysis process, providing automated feedback on the proposed design and generating a graphical summary that aids communication with colleagues, funders, regulatory authorities, and the wider scientific community. It will have an important role in addressing causes of irreproducibility. PMID:28957312

Experimental study of adaptive pointing and tracking for large flexible space structures

NASA Technical Reports Server (NTRS)

Boussalis, D.; Bayard, D. S.; Ih, C.; Wang, S. J.; Ahmed, A.

1991-01-01

This paper describes an experimental study of adaptive pointing and tracking control for flexible spacecraft conducted on a complex ground experiment facility. The algorithm used in this study is based on a multivariable direct model reference adaptive control law. Several experimental validation studies were performed earlier using this algorithm for vibration damping and robust regulation, with excellent results. The current work extends previous studies by addressing the pointing and tracking problem. As is consistent with an adaptive control framework, the plant is assumed to be poorly known to the extent that only system level knowledge of its dynamics is available. Explicit bounds on the steady-state pointing error are derived as functions of the adaptive controller design parameters. It is shown that good tracking performance can be achieved in an experimental setting by adjusting adaptive controller design weightings according to the guidelines indicated by the analytical expressions for the error.

Clinical Investigation Program, RCS MED-300 (RI).

DTIC Science & Technology

1984-10-01

temperature/dry. Technical Approach: 1) Experimental desion: a post-test only, equivalent - group experimental design will be used in this study. Random...5650 * It. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE Commander October 1984 Dwight David Eisenhower Army Medical Center 1s. NUMBEROFPAGES...Fort Gordon, Georgia 30905-5650 210 14. MONITORING AGENCY NAME I ADORESS(11 different from Controlling Offce) IS. SECURITY CLASS. (of tAle MP*H

Evaluation of binder aging and its influence in aging of hot mix asphalt concrete : literature review and experimental design.

DOT National Transportation Integrated Search

2009-02-01

Binder oxidation in pavements and its impact on pavement performance has been addressed by : numerous laboratory studies of binder oxidation chemistry, reaction kinetics, and hardening and its impact on : mixture fatigue. Studies also have included s...

Best practices for using natural experiments to evaluate retail food and beverage policies and interventions.

PubMed

Taillie, Lindsey Smith; Grummon, Anna H; Fleischhacker, Sheila; Grigsby-Toussaint, Diana S; Leone, Lucia; Caspi, Caitlin Eicher

2017-12-01

Policy and programmatic change in the food retail setting, including excise taxes on beverages with added-caloric sweeteners, new supermarkets in food deserts, and voluntary corporate pledges, often require the use of natural experimental evaluation for impact evaluation when randomized controlled trials are not possible. Although natural experimental studies in the food retail setting provide important opportunities to test how nonrandomized interventions affect behavioral and health outcomes, researchers face several key challenges to maintaining strong internal and external validity when conducting these studies. Broadly, these challenges include 1) study design and analysis; 2) selection of participants, selection of measures, and obtainment of data; and 3) real-world considerations. This article addresses these challenges and different approaches to meeting them. Case studies are used to illustrate these approaches and to highlight advantages and disadvantages of each approach. If the trade-offs required to address these challenges are carefully considered, thoughtful natural experimental evaluations can minimize bias and provide critical information about the impacts of food retail interventions to a variety of stakeholders, including the affected population, policymakers, and food retailers. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

An Experimental Study of Water Injection into a Rolls-Royce Model 250-C20B Turboshaft Gas Turbine

DTIC Science & Technology

2008-05-06

0704-0188), Washington, DC 20503. 1. AGENCY USE ONLY (Leave blank) 2. REPORT DATE 6 May 2008 3. REPORT TYPE AND DATE COVERED 4...9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING AGENCY REPORT NUMBER US Naval Academy... used an instrumented Model 250-C20B gas turbine and an original water spray system. Temperatures and pressures were measured for each of the gas

The Adsorption of Bromide Ion at Mercury from Propylene Carbonate Solutions of Constant Ionic Strength

DTIC Science & Technology

1991-05-20

Chemistry University of California Davis, CA 95616 * To whom correspondence should be addressed. t Permanent address: Instituto de Fisica e Quimica ...I]. In the case of Br- ion adsorption at Hg, studies have been carried out in water [2-4] and N- methylformamide solutions [5,6] of both varying and...discussed with respect to current theoretical developments. 4 Experimental Differential capacity against potential data were obtained for the mercury

Quasi-experimental evaluation of a substance use awareness educational intervention for nursing students.

PubMed

Cadiz, David M; O'Neill, Chris; Butell, Sue S; Epeneter, Beverly J; Basin, Basilia

2012-07-01

This article reports on a study that evaluated the effectiveness of an educational intervention, Addressing Nurse Impairment, for addressing nursing students' knowledge acquisition, changes in self-efficacy to intervene, and changes in substance abuse stigma. A gap exists in nursing students' education regarding the risks of addiction within the profession and how to handle a colleague suspected of having a substance use disorder. The seminar was adapted from an existing evidence-based prevention program called Team Awareness, as well as information from focus groups and a pilot test. A quasi-experimental pretest-posttest design was used to evaluate the effect of the seminar. When the control and experimental groups were compared, the results indicated that the seminar significantly affected knowledge and self-efficacy to intervene but did not significantly affect stigma. This research contributes to the body of evidence related to educational interventions for nursing students regarding substance abuse in the nursing profession. Copyright 2012, SLACK Incorporated.

Olympic Education as a Factor of Socialization of Preschoolers

ERIC Educational Resources Information Center

Varfolomeeva, Zoya S.; Surinov, Ilya A.

2016-01-01

The purpose of this study is theoretical substantiation and experimental confirmation of importance of the Olympic education as a socialization factor of the preschoolers. To address the study issues, theoretical methods of analysis, generalization and systematization as well as personal and activity approaches were applied. The older preschoolers…

Animation-Based Learning in Geology: Impact of Animations Coupled with Seductive Details

ERIC Educational Resources Information Center

Clayton, Rodney L.

2016-01-01

Research is not clear on how to address the difficulty students have conceptualizing geologic processes and phenomena. This study investigated how animations coupled with seductive details effect learners' situational interest and emotions. A quantitative quasi-experimental study employing an independent-measures factorial design was used. The…

Using Reading as an Automated Learning Tool

ERIC Educational Resources Information Center

Ruiz Fodor, Ana

2017-01-01

The problem addressed in this quantitative experimental study was that students were having more difficulty learning from audiovisual lessons than necessary because educators had eliminated textual references, based on early findings from CLT research. In more recent studies, CLT researchers estimated that long-term memory schemas may be used by…

Efficiency of a Care Coordination Model: A Randomized Study with Stroke Patients

ERIC Educational Resources Information Center

Claiborne, Nancy

2006-01-01

Objectives: This study investigated the efficiency of a social work care coordination model for stroke patients. Care coordination addresses patient care and treatment resources across the health care system to reduce risk, improve clinical outcomes, and maximize efficiency. Method: A randomly assigned, pre-post experimental design measured…

Protocol for Reliability Assessment of Structural Health Monitoring Systems Incorporating Model-assisted Probability of Detection (MAPOD) Approach

DTIC Science & Technology

2011-09-01

a quality evaluation with limited data, a model -based assessment must be...that affect system performance, a multistage approach to system validation, a modeling and experimental methodology for efficiently addressing a ...affect system performance, a multistage approach to system validation, a modeling and experimental methodology for efficiently addressing a wide range

Aerothermal Testing for Project Orion Crew Exploration Vehicle

NASA Technical Reports Server (NTRS)

Berry, Scott A.; Horvath, Thomas J.; Lillard, Randolph P.; Kirk, Benjamin S.; Fischer-Cassady, Amy

2009-01-01

The Project Orion Crew Exploration Vehicle aerothermodynamic experimentation strategy, as it relates to flight database development, is reviewed. Experimental data has been obtained to both validate the computational predictions utilized as part of the database and support the development of engineering models for issues not adequately addressed with computations. An outline is provided of the working groups formed to address the key deficiencies in data and knowledge for blunt reentry vehicles. The facilities utilized to address these deficiencies are reviewed, along with some of the important results obtained thus far. For smooth wall comparisons of computational convective heating predictions against experimental data from several facilities, confidence was gained with the use of algebraic turbulence model solutions as part of the database. For cavities and protuberances, experimental data is being used for screening various designs, plus providing support to the development of engineering models. With the reaction-control system testing, experimental data were acquired on the surface in combination with off-body flow visualization of the jet plumes and interactions. These results are being compared against predictions for improved understanding of aftbody thermal environments and uncertainties.

Alcohol and Sexuality Research in the AIDS Era: Trends in Publication Activity, Target Populations and Research Design

PubMed Central

George, William H.

2009-01-01

Research addressing relationships between alcohol and human sexuality has proliferated, due in part to efforts to characterize alcohol's role in HIV risk behavior. This study provides a descriptive review of the alcohol–sexuality literature, using abstracts from 264 identified studies to estimate changes in publication activity, target populations, and the prevalence of HIV-related studies over time. We also examine methodological trends by estimating the prevalence of experimental vs. non-experimental studies. Findings show considerable increases in research activity and diversity of populations studied since the mid-1980's and highlight the emergence of HIV-related studies as a focal point of alcohol–sexuality research efforts. Results also demonstrate a substantial decline in the proportion of studies utilizing experimental methods, in part because of frequent use of non-experimental approaches in studies of alcohol and HIV risk behavior. We discuss implications and review the role of experiments in evaluating causal relationships between alcohol and sexual risk behavior. PMID:16897352

Alcohol and sexuality research in the AIDS era: trends in publication activity, target populations and research design.

PubMed

Hendershot, Christian S; George, William H

2007-03-01

Research addressing relationships between alcohol and human sexuality has proliferated, due in part to efforts to characterize alcohol's role in HIV risk behavior. This study provides a descriptive review of the alcohol-sexuality literature, using abstracts from 264 identified studies to estimate changes in publication activity, target populations, and the prevalence of HIV-related studies over time. We also examine methodological trends by estimating the prevalence of experimental vs. non-experimental studies. Findings show considerable increases in research activity and diversity of populations studied since the mid-1980's and highlight the emergence of HIV-related studies as a focal point of alcohol-sexuality research efforts. Results also demonstrate a substantial decline in the proportion of studies utilizing experimental methods, in part because of frequent use of non-experimental approaches in studies of alcohol and HIV risk behavior. We discuss implications and review the role of experiments in evaluating causal relationships between alcohol and sexual risk behavior.

Vulnerable Subjects: Why Does Informed Consent Matter?

PubMed

Goodwin, Michele

2016-09-01

This special issue of the Journal Law, Medicine & Ethics takes up the concern of informed consent, particularly in times of controversy. The dominant moral dilemmas that frame traditional bioethical concerns address medical experimentation on vulnerable subjects; physicians assisting their patients in suicide or euthanasia; scarce resource allocation and medical futility; human trials to develop drugs; organ and tissue donation; cloning; xenotransplantation; abortion; human enhancement; mandatory vaccination; and much more. The term "bioethics" provides a lens, language, and guideposts to the study of medical ethics. It is worth noting, however, that medical experimentation is neither new nor exclusive to one country. Authors in this issue address thorny subjects that span borders and patients: from matters dealing with children and vaccination to the language and perception of consent. © 2016 American Society of Law, Medicine & Ethics.

78 FR 51678 - Market Tests of Experimental Postal Products

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-21

...] Market Tests of Experimental Postal Products AGENCY: Postal Regulatory Commission. ACTION: Proposed rule... tests of experimental products. The proposed rules address the contents of market test filings, describe... Tests I. Introduction The Commission proposes to establish rules governing market tests of experimental...

Experimental Studies on the Effects of Thermal Bumps in the Flow-Field around a Flat Plate using a Hypersonic Wind Tunnel

DTIC Science & Technology

2012-07-01

Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1 hour per response, including the...PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1 . REPORT DATE (DD-MM-YYYY) 12 July 2012 2. REPORT TYPE Final Report 3. DATES COVERED...From – To) 1 October 2008 – 31 January 2012 4. TITLE AND SUBTITLE Experimental Studies on the Effects of Thermal Bumps in the Flow-Field around a

Environmental & Water Quality Operational Studies: Improved Description of Selective Withdrawal through Point Sinks.

DTIC Science & Technology

1987-03-01

Sink’ by G. A. Lawrence," Second International Symposium on Stratified Flows, Trondheim, Norway. Hino, M ., and Furusawa , M . 1969. "Experiments on...Hydrulic LaoratryInvironmental Laboratory 6c ADDRESS (01y. Stat,, aed lV~IP b ADDRESS (CRY. Stat, M ad Wd) PO Box 631 PO Box631 Vicksburg, NS 39180-0631...than 1 cm dur- ing testing and that diffuse interfaces resulted in an experimentally 11 / , . .. , n_ .. mm m m I n ---- mm __ro ___ III I IIIIIj .4

The Effect of Creative Drama as a Method on Skills: A Meta-Analysis Study

ERIC Educational Resources Information Center

Ulubey, Özgür

2018-01-01

The aim of the current study was to synthesize the findings of experimental studies addressing the effect of the creative drama method on the skills of students. Research data were derived from ProQuest Citations, Web of Science, Google Academic, National Thesis Center, EBSCO, ERIC, Taylor & Francis Online, and ScienceDirect databases using…

Using Popular Culture to Teach the Community College Business Curriculum: A Comparative Study

ERIC Educational Resources Information Center

Passero, Thomas

2011-01-01

This study addressed a need for comprehensive quantitative empirical studies to determine the effectiveness of using popular culture media as a teaching technique. A quasi-experimental design was implemented to examine whether a group of community college students taking a first-semester introduction to business course who were exposed to a…

LifeSat - A satellite for space biological research

NASA Technical Reports Server (NTRS)

Halstead, Thora W.; Morey-Holton, Emily R.

1990-01-01

The LifeSat Program addresses the need for continuing access by biological scientists to space experimentation by accommodating a wide range of experiments involving animals and plants for durations up to 60 days in an unmanned satellite. The program will encourage interdisciplinary and international cooperation at both the agency and scientist levels, and will provide a recoverable, reusable facility for low-cost missions addressing key scientific issues that can only be answered by space experimentation. It will provide opportunities for research in gravitational biology and on the effects of cosmic radiation on life systems. The scientific aspects of LifeSat are addressed here.

Experimental Studies of Premixed Flame Structure and Propagation Characteristics in Compressible Flow

DTIC Science & Technology

2015-07-14

turbulence has not been addressed experimentally. These issues are important for next generation high-pressure gas turbine , and especially, for scramjet...subsonic wind tunnel capable of Mach numbers in excess of Mach 0.7, with the ability to generate varying turbulence levels and accommodate fuel injection...square O- ring stock seal mounted in the corners to aid in locating the individual seals and window panes, as well as RTV silicone gasket seal galleries

Past Tense Morphology in Cri Du Chat Syndrome: Experimental Evidence

ERIC Educational Resources Information Center

Wium, Kristin; Kristoffersen, Kristian Emil

2008-01-01

It has been observed that persons with Cri du chat syndrome (CDCS) have poor language production. However, very few studies have addressed the question whether all aspects of language production are equally afflicted, or whether there are differences between for instance phonological and morphological abilities. The present study was aimed at…

The Earth's Core: How Does It Work? Perspectives in Science. Number 1.

ERIC Educational Resources Information Center

Carnegie Institution of Washington, Washington, DC.

Various research studies designed to enhance knowledge about the earth's core are discussed. Areas addressed include: (1) the discovery of the earth's core; (2) experimental approaches used in studying the earth's core (including shock-wave experiments and experiments at high static pressures), the search for the core's light elements, the…

Research Directions for Cyber Experimentation: Workshop Discussion Analysis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

DeWaard, Elizabeth; Deccio, Casey; Fritz, David Jakob

Sandia National Laboratories hosted a workshop on August 11, 2017 entitled "Research Directions for Cyber Experimentation," which focused on identifying and addressing research gaps within the field of cyber experimentation , particularly emulation testbeds . This report mainly documents the discussion toward the end of the workshop, which included research gaps such as developing a sustainable research infrastructure, exp anding cyber experimentation, and making the field more accessible to subject matter experts who may not have a background in computer science . Other gaps include methodologies for rigorous experimentation, validation, and uncertainty quantification, which , if addressed, also have themore » potential to bridge the gap between cyber experimentation and cyber engineering. Workshop attendees presented various ways to overcome these research gaps, however the main conclusion for overcoming these gaps is better commun ication through increased workshops, conferences, email lists, and slack chann els, among other opportunities.« less

Predictive Surface Complexation Modeling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sverjensky, Dimitri A.

Surface complexation plays an important role in the equilibria and kinetics of processes controlling the compositions of soilwaters and groundwaters, the fate of contaminants in groundwaters, and the subsurface storage of CO 2 and nuclear waste. Over the last several decades, many dozens of individual experimental studies have addressed aspects of surface complexation that have contributed to an increased understanding of its role in natural systems. However, there has been no previous attempt to develop a model of surface complexation that can be used to link all the experimental studies in order to place them on a predictive basis. Overall,more » my research has successfully integrated the results of the work of many experimentalists published over several decades. For the first time in studies of the geochemistry of the mineral-water interface, a practical predictive capability for modeling has become available. The predictive correlations developed in my research now enable extrapolations of experimental studies to provide estimates of surface chemistry for systems not yet studied experimentally and for natural and anthropogenically perturbed systems.« less

Direct experimental visualization of the global Hamiltonian progression of two-dimensional Lagrangian flow topologies from integrable to chaotic state.

PubMed

Baskan, O; Speetjens, M F M; Metcalfe, G; Clercx, H J H

2015-10-01

Countless theoretical/numerical studies on transport and mixing in two-dimensional (2D) unsteady flows lean on the assumption that Hamiltonian mechanisms govern the Lagrangian dynamics of passive tracers. However, experimental studies specifically investigating said mechanisms are rare. Moreover, they typically concern local behavior in specific states (usually far away from the integrable state) and generally expose this indirectly by dye visualization. Laboratory experiments explicitly addressing the global Hamiltonian progression of the Lagrangian flow topology entirely from integrable to chaotic state, i.e., the fundamental route to efficient transport by chaotic advection, appear non-existent. This motivates our study on experimental visualization of this progression by direct measurement of Poincaré sections of passive tracer particles in a representative 2D time-periodic flow. This admits (i) accurate replication of the experimental initial conditions, facilitating true one-to-one comparison of simulated and measured behavior, and (ii) direct experimental investigation of the ensuing Lagrangian dynamics. The analysis reveals a close agreement between computations and observations and thus experimentally validates the full global Hamiltonian progression at a great level of detail.

Novel utilization of the outer membrane proteins for the identification and differentiation of pathogenic versus nonpathogenic microbial strains using mass spectrometry-based proteomics approach

NASA Astrophysics Data System (ADS)

Jabbour, Rabih E.; Wade, Mary; Deshpande, Samir V.; McCubbin, Patrick; Snyder, A. Peter; Bevilacqua, Vicky

2012-06-01

Mass spectrometry based proteomic approaches are showing promising capabilities in addressing various biological and biochemical issues. Outer membrane proteins (OMPs) are often associated with virulence in gram-negative pathogens and could prove to be excellent model biomarkers for strain level differentiation among bacteria. Whole cells and OMP extracts were isolated from pathogenic and non-pathogenic strains of Francisella tularensis, Burkholderia thailandensis, and Burkholderia mallei. OMP extracts were compared for their ability to differentiate and delineate the correct database organism to an experimental sample and for the degree of dissimilarity to the nearest-neighbor database strains. This study addresses the comparative experimental proteome analyses of OMPs vs. whole cell lysates on the strain-level discrimination among gram negative pathogenic and non-pathogenic strains.

Addressing Learning Disabilities with UDL and Technology: Strategic Reader

ERIC Educational Resources Information Center

Hall, Tracey E.; Cohen, Nicole; Vue, Ge; Ganley, Patricia

2015-01-01

CAST created "Strategic Reader," a technology-based system blending Universal Design for Learning (UDL) and Curriculum-Based Measurement (CBM) in a digital learning environment to improve reading comprehension instruction. This experimental study evaluates the effectiveness of Strategic Reader using two treatment conditions for measuring…

Is Sexual Objectification and Victimization of Females in Video Games Associated With Victim Blaming or Victim Empathy?

PubMed

Beck, Victoria; Rose, Chris

2018-04-01

The goal of this study was to investigate whether the sexual objectification and virtual violence against females in video games increases negative attitudes toward females, when addressing a variety of noted methodological issues. Study participants were randomly assigned to a control group, where participants played Madden NFL 12, or an experimental group, where participants played Grand Theft Auto. In the experimental group, participants played the game with a confederate, who exposed participants to sexual objectification and violence against females. Study results indicated that both the experimental and control groups had equivalently low levels of rape myth acceptance prior to game play. Immediately after game play, there still was no statistically significant difference in rape myth acceptance between groups; however, there was a decrease in rape myth acceptance for the experimental group. The decrease in rape myth acceptance continued and magnified for the experimental group, over time, to the point of creating a statistically significant difference between the two groups for the follow-up measure at the end of the study.

"PCI Reading Program": The Final Report of a Three Year Experimental Study in Brevard Public Schools and Miami-Dade County Public Schools. Research Report

ERIC Educational Resources Information Center

Toby, Megan; Jaciw, Andrew; Ma, Boya; Lipton, Akiko

2011-01-01

PCI Education conducted a three-year longitudinal study to determine the comparative effectiveness of the "PCI Reading Program" ("PCI") for students with severe disabilities as implemented in Florida's Brevard Public Schools and Miami-Dade County Public Schools. The primary question addressed by the study is whether students…

To Give Control to Learners or Not? A Comparative Study of Two Ways of Teaching Listening

ERIC Educational Resources Information Center

Wang, Yushan

2010-01-01

This paper reports a quasi-experimental study that was carried out in listening classes to address the following questions: What control do students expect in the listening classroom? What are the effects of the "zero class hour" way of teaching listening when more control is given to the students? The study was conducted at Huaiyin…

Consequences of non-random species loss for decomposition dynamics: Experimental evidence for additive and non-additive effects

Treesearch

Becky A. Ball; Mark D. Hunter; John S. Kominoski; Christopher M. Swan; Mark A. Bradford

2008-01-01

Although litter decomposition is a fundamental ecological process, most of our understanding comes from studies of single-species decay. Recently, litter-mixing studies have tested whether monoculture data can be applied to mixed-litter systems. These studies have mainly attempted to detect non-additive effects of litter mixing, which address potential consequences of...

Direct experimental observation of nonclassicality in ensembles of single-photon emitters

NASA Astrophysics Data System (ADS)

Moreva, E.; Traina, P.; Forneris, J.; Degiovanni, I. P.; Ditalia Tchernij, S.; Picollo, F.; Brida, G.; Olivero, P.; Genovese, M.

2017-11-01

In this work we experimentally demonstrate a recently proposed criterion addressed to detect nonclassical behavior in the fluorescence emission of ensembles of single-photon emitters. In particular, we apply the method to study clusters of nitrogen-vacancy centers in diamond characterized with single-photon-sensitive confocal microscopy. Theoretical considerations on the behavior of the parameter at any arbitrary order in the presence of Poissonian noise are presented and, finally, the opportunity of detecting manifold coincidences is discussed.

Unsteady Low Reynolds Number Aerodynamics for Micro Air Vehicles (MAVs)

DTIC Science & Technology

2010-05-01

and Colonius, T. " Control of a Semi-Circular Planform Wing in a "Gusting" Unsteady Freestream Flow: I- Experimental Issues". AIAA-2008-3976, 2008...information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD...Return 96 6.9.1. Introduction 96 6.9.2. Experimental Parameter Study with Dye Injection 96 6.9.3. Qualitative vs. Quantitative Flow Visualization

Demand artifact: objectively detecting biased participants in advertising research.

PubMed

Miller, Felicia; Schertzer, Susan

2014-12-01

Detecting and reducing the effect of biased participants continues to be an important task for researchers. However, the lack of objective measures to assess demand artifact has made it difficult to effectively address this issue. This paper reports two experiments that apply a theory-based post-experimental inquiry that can systematically identify biased participants in consumer research. The results demonstrate how easily and effectively researchers can incorporate this tool into experimental studies of all types and reduce the likelihood of systematic error.

Exploring the costs and benefits of social information use: an appraisal of current experimental evidence.

PubMed

Rieucau, Guillaume; Giraldeau, Luc-Alain

2011-04-12

Research on social learning has focused traditionally on whether animals possess the cognitive ability to learn novel motor patterns from tutors. More recently, social learning has included the use of others as sources of inadvertent social information. This type of social learning seems more taxonomically widespread and its use can more readily be approached as an economic decision. Social sampling information, however, can be tricky to use and calls for a more lucid appraisal of its costs. In this four-part review, we address these costs. Firstly, we address the possibility that only a fraction of group members are actually providing social information at any one time. Secondly, we review experimental research which shows that animals are circumspect about social information use. Thirdly, we consider the cases where social information can lead to incorrect decisions and finally, we review studies investigating the effect of social information quality. We address the possibility that using social information or not is not a binary decision and present results of a study showing that nutmeg mannikins combine both sources of information, a condition that can lead to the establishment of informational cascades. We discuss the importance of empirically investigating the economics of social information use.

Effects of an Adolescent Literacy Program on Ninth Grade Students Deficient in Literacy Skills

ERIC Educational Resources Information Center

Knuchel, Brian

2010-01-01

Research indicates that many adolescent students struggle with reading skills. Accordingly, this quantitative study attempted to address the problem of ninth-grade students entering high school deficient in literacy skills. The purpose of this non-experimental study was to investigate the effects a remedial reading program called Ramp-Up Literacy…

Investigating the Effectiveness of Audio Input Enhancement on EFL Learners' Retention of Intensifiers

ERIC Educational Resources Information Center

Negari, Giti Mousapour; Azizi, Aliye; Arani, Davood Khedmatkar

2018-01-01

The present study attempted to investigate the effects of audio input enhancement on EFL learners' retention of intensifiers. To this end, two research questions were formulated. In order to address these research questions, this study attempted to reject two null hypotheses. Pretest-posttest control group quasi-experimental design was employed to…

Contrasting effects of insect exclusion on wood loss in a temperate forest

Treesearch

Michael Ulyshen; Terry Wagner; Joseph E. Mulrooney

2014-01-01

Experimental efforts to determine how insects influence terrestrial wood decomposition are few, especially in temperate regions. To address this need, a five-year exclusion study was conducted in northern Mississippi, U.S.A., to quantify insect contributions to wood decay using one-meter loblolly pine (Pinus taeda L.) bolts. The study included three...

BAGHEERA: A new experimental facility at CEA / Valduc for actinides studies under high dynamic loading

NASA Astrophysics Data System (ADS)

Roy, G.; Llorca, F.; Lanier, G.; Lamalle, S.; Beaulieu, J.; Antoine, P.; Martinuzzi, P.

2006-08-01

This paper is a technical presentation about a new experimental facility recently developed at CEA/Valduc, BAGHEERA, a French acronym for “Hopkinson And High Speed Experiments Glove Box”. This facility is used since mid-2003 to characterize the physical and mechanical behaviour of actinides under high dynamic loadings. For this purpose, four basic experimental devices are confined inside a single glove box: a 50 mm bore diameter single stage light gas gun, two compression and torsion split Hopkinson bars (SHPB and TSHB respectively) and a Taylor test device (TTD). Design and technical data on the experimental equipment are addressed, with a particular emphasis on the gas gun specific features due to actinide applications.

Optoelectronic Terminal-Attractor-Based Associative Memory

NASA Technical Reports Server (NTRS)

Liu, Hua-Kuang; Barhen, Jacob; Farhat, Nabil H.

1994-01-01

Report presents theoretical and experimental study of optically and electronically addressable optical implementation of artificial neural network that performs associative recall. Shows by computer simulation that terminal-attractor-based associative memory can have perfect convergence in associative retrieval and increased storage capacity. Spurious states reduced by exploiting terminal attractors.

75 FR 53325 - Proposed Scientific Integrity Policy of the Department of the Interior

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-31

... September 20, 2010. ADDRESSES: Send comments to: [email protected]ios.doi.gov . FOR FURTHER INFORMATION... scientific products, or on documents compiled and translated from scientific products, to ensure that agency... involving inventorying, monitoring, experimentation, study, research, modeling, and scientific assessment...

The LENS Facilities and Experimental Studies to Evaluate the Modeling of Boundary Layer Transition, Shock/Boundary Layer Interaction, Real Gas, Radiation and Plasma Phenomena in Contemporary CFD Codes

DTIC Science & Technology

2010-04-01

Layer Interaction, Real Gas, Radiation and Plasma Phenomena in Contemporary CFD Codes Michael S. Holden, PhD CUBRC , Inc. 4455 Genesee Street Buffalo...NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) CUBRC , Inc. 4455 Genesee Street Buffalo, NY 14225, USA 8. PERFORMING...HyFly Navy EMRG Reentry-F Slide 2 X-43 HIFiRE-2 Figure 17: Transition in Hypervelocity Flows: CUBRC Focus – Fully Duplicated Ground Test

Experimental Evolution with Caenorhabditis Nematodes

PubMed Central

Teotónio, Henrique; Estes, Suzanne; Phillips, Patrick C.; Baer, Charles F.

2017-01-01

The hermaphroditic nematode Caenorhabditis elegans has been one of the primary model systems in biology since the 1970s, but only within the last two decades has this nematode also become a useful model for experimental evolution. Here, we outline the goals and major foci of experimental evolution with C. elegans and related species, such as C. briggsae and C. remanei, by discussing the principles of experimental design, and highlighting the strengths and limitations of Caenorhabditis as model systems. We then review three exemplars of Caenorhabditis experimental evolution studies, underlining representative evolution experiments that have addressed the: (1) maintenance of genetic variation; (2) role of natural selection during transitions from outcrossing to selfing, as well as the maintenance of mixed breeding modes during evolution; and (3) evolution of phenotypic plasticity and its role in adaptation to variable environments, including host–pathogen coevolution. We conclude by suggesting some future directions for which experimental evolution with Caenorhabditis would be particularly informative. PMID:28592504

Histochemical stains as promising means for the laser histochemical surgery of a number of pathologies

NASA Astrophysics Data System (ADS)

Piruzyan, L. A.; Mikhailovskiy, Ye. M.; Piruzyan, A. L.

1999-12-01

The directions of laboratory and clinical studies oriented to experimental confirmation of the priority concept of `laser histochemical surgery' are presented. The goal of the studies is reproduction on experimental model of a number of pathologies (in vivo and in vitro) of the `sensitization to laser radiation by staining' effect. Testing of the histochemical stains as sensitizers to laser irradiation of their `address substrates', i.e. vitally stained intracellular structures which participate in the pathologic processes evolution is under planning. The processes include: (a) metabolic disorders in the brain cells, i.e. disseminated sclerosis; (b) generalized metabolic disorders- -mucopolysaccharidosis and collagenosises (periarteritis nodosa, rheumatism, rheumatoid arthritis, sclerodermia); (3) metabolic disorders in individual organs--vessel atherosclerosis, hypercholesterolemia, myocardial infarction, cardiosclerosis, caries and parodontosis. The conditions of the studies are detailed in the recommendations along the positions: (1) disease name; (2) disease characteristics: (a) pathomorphologic, (b) biochemical; (3) stains revealing the disease signs and recommended for testing; (4) `address substrates' of the stains that are targets for laser radiation; (5) lasers recommended for the testing after the cells staining in vivo in the corresponding pathology; (6) experimental models of the pathologies suggested for the testing; (7) criteria of the stain efficiency as target sensitizer to the laser light (criteria of the `laser sensitization by staining' efficiency). Possible perspectives for the experimental clinical medicine are indicated of common histochemical stains and lasers use and of practice introduction of the `laser histochemical surgery' in the case the described concept is confirmed in experiments and clinically.

A practical guide and perspectives on the use of experimental pain modalities with children and adolescents

PubMed Central

Birnie, Kathryn A; Caes, Line; Wilson, Anna C; Williams, Sara E; Chambers, Christine T

2014-01-01

SUMMARY Use of experimental pain is vital for addressing research questions that would otherwise be impossible to examine in the real world. Experimental induction of pain in children is highly scrutinized given the potential for harm and lack of direct benefit to a vulnerable population. However, its use has critically advanced our understanding of the mechanisms, assessment and treatment of pain in both healthy and chronically ill children. This article introduces various experimental pain modalities, including the cold pressor task, the water load symptom provocation test, thermal pain, pressure pain and conditioned pain modulation, and discusses their application for use with children and adolescents. It addresses practical implementation and ethical issues, as well as the advantages and disadvantages offered by each task. The incredible potential for future research is discussed given the array of experimental pain modalities now available to pediatric researchers. PMID:24641434

Superfluid qubit systems with ring shaped optical lattices

PubMed Central

Amico, Luigi; Aghamalyan, Davit; Auksztol, Filip; Crepaz, Herbert; Dumke, Rainer; Kwek, Leong Chuan

2014-01-01

We study an experimentally feasible qubit system employing neutral atomic currents. Our system is based on bosonic cold atoms trapped in ring-shaped optical lattice potentials. The lattice makes the system strictly one dimensional and it provides the infrastructure to realize a tunable ring-ring interaction. Our implementation combines the low decoherence rates of neutral cold atoms systems, overcoming single site addressing, with the robustness of topologically protected solid state Josephson flux qubits. Characteristic fluctuations in the magnetic fields affecting Josephson junction based flux qubits are expected to be minimized employing neutral atoms as flux carriers. By breaking the Galilean invariance we demonstrate how atomic currents through the lattice provide an implementation of a qubit. This is realized either by artificially creating a phase slip in a single ring, or by tunnel coupling of two homogeneous ring lattices. The single qubit infrastructure is experimentally investigated with tailored optical potentials. Indeed, we have experimentally realized scaled ring-lattice potentials that could host, in principle, n ~ 10 of such ring-qubits, arranged in a stack configuration, along the laser beam propagation axis. An experimentally viable scheme of the two-ring-qubit is discussed, as well. Based on our analysis, we provide protocols to initialize, address, and read-out the qubit. PMID:24599096

Phonological Advance Planning in Sentence Production

ERIC Educational Resources Information Center

Oppermann, Frank; Jescheniak, Jorg D.; Schriefers, Herbert

2010-01-01

Our study addresses the scope of phonological advance planning during sentence production using a novel experimental procedure. The production of German sentences in various syntactic formats (SVO, SOV, and VSO) was cued by presenting pictures of the agents of previously memorized agent-action-patient scenes. To tap the phonological activation of…

The Neural Basis of Cognitive Control: Response Selection and Inhibition

ERIC Educational Resources Information Center

Goghari, Vina M.; MacDonald, Angus W., III

2009-01-01

The functional neuroanatomy of tasks that recruit different forms of response selection and inhibition has to our knowledge, never been directly addressed in a single fMRI study using similar stimulus-response paradigms where differences between scanning time and sequence, stimuli, and experimenter instructions were minimized. Twelve right-handed…

Assessing an Introduction to Systems Thinking

ERIC Educational Resources Information Center

Monroe, Martha C.; Plate, Richard R.; Colley, Lara

2015-01-01

This research study investigated the learning outcomes of a brief systems thinking intervention at the undergraduate level. A pre/post experimental design (n = 50) was used to address two primary questions: (1) Can a brief introduction to systems thinking improve students' understanding of systems thinking? and (2) Which teaching method (of…

Ebola vaccine development plan: ethics, concerns and proposed measures.

PubMed

Folayan, Morenike Oluwatoyin; Yakubu, Aminu; Haire, Bridget; Peterson, Kristin

2016-02-08

The global interest in developing therapies for Ebola infection management and its prevention is laudable. However the plan to conduct an emergency immunization program specifically for healthcare workers using experimental vaccines raises some ethical concerns. This paper shares perspectives on these concerns and suggests how some of them may best be addressed. The recruitment of healthcare workers for Ebola vaccine research has challenges. It could result in coercion of initially dissenting healthcare workers to assist in the management of EVD infected persons due to mistaken beliefs that the vaccine offers protection. It could also affect equity and justice. For example, where people who are not skilled health care professionals but who provide care to patients infected with Ebola (such as in home care settings) are not prioritized for vaccination. The possibility of study participants contracting Ebola infection despite the use of experimental vaccine, and the standard of care they would receive, needs to be addressed clearly, transparently and formalized as part of the ethics review process. Future access to study products in view of current status of the TRIPS agreement needs to be addressed. Finally, broad stakeholder engagement at local, regional and international levels needs to be promoted using available communication channels to engage local, regional and international support. These same concerns are applicable for current and future epidemics. Successful Ebola vaccine development research requires concerted efforts at public dialogue to address misconceptions, equity and justice in participant selection, and honest discussions about risks, benefits and future access. Public dialogue about Ebola vaccine research plans is crucial and should be conducted by trusted locals and negotiated between communities, researchers and ethics committees in research study sites.

mHealth for HIV Treatment & Prevention: A Systematic Review of the Literature

PubMed Central

Catalani, Caricia; Philbrick, William; Fraser, Hamish; Mechael, , Patricia; Israelski, Dennis M.

2013-01-01

This systematic review assesses the published literature to describe the landscape of mobile health technology (mHealth) for HIV/AIDS and the evidence supporting the use of these tools to address the HIV prevention, care, and treatment cascade. The speed of innovation, broad range of initiatives and tools, and heterogeneity in reporting have made it difficult to uncover and synthesize knowledge on how mHealth tools might be effective in addressing the HIV pandemic. To do address this gap, a team of reviewers collected literature on the use of mobile technology for HIV/AIDS among health, engineering, and social science literature databases and analyzed a final set of 62 articles. Articles were systematically coded, assessed for scientific rigor, and sorted for HIV programmatic relevance. The review revealed evidence that mHealth tools support HIV programmatic priorities, including: linkage to care, retention in care, and adherence to antiretroviral treatment. In terms of technical features, mHealth tools facilitate alerts and reminders, data collection, direct voice communication, educational messaging, information on demand, and more. Studies were mostly descriptive with a growing number of quasi-experimental and experimental designs. There was a lack of evidence around the use of mHealth tools to address the needs of key populations, including pregnant mothers, sex workers, users of injection drugs, and men who have sex with men. The science and practice of mHealth for HIV are evolving rapidly, but still in their early stages. Small-scale efforts, pilot projects, and preliminary descriptive studies are advancing and there is a promising trend toward implementing mHealth innovation that is feasible and acceptable within low-resource settings, positive program outcomes, operational improvements, and rigorous study design PMID:24133558

Experimental Models to Study the Role of Microbes in Host-Parasite Interactions.

PubMed

Hahn, Megan A; Dheilly, Nolwenn M

2016-01-01

Until recently, parasitic infections have been primarily studied as interactions between the parasite and the host, leaving out crucial players: microbes. The recent realization that microbes play key roles in the biology of all living organisms is not only challenging our understanding of host-parasite evolution, but it also provides new clues to develop new therapies and remediation strategies. In this paper we provide a review of promising and advanced experimental organismal systems to examine the dynamic of host-parasite-microbe interactions. We address the benefits of developing new experimental models appropriate to this new research area and identify systems that offer the best promises considering the nature of the interactions among hosts, parasites, and microbes. Based on these systems, we identify key criteria for selecting experimental models to elucidate the fundamental principles of these complex webs of interactions. It appears that no model is ideal and that complementary studies should be performed on different systems in order to understand the driving roles of microbes in host and parasite evolution.

Experimental and Computational Studies of Cortical Neural Network Properties Through Signal Processing

NASA Astrophysics Data System (ADS)

Clawson, Wesley Patrick

Previous studies, both theoretical and experimental, of network level dynamics in the cerebral cortex show evidence for a statistical phenomenon called criticality; a phenomenon originally studied in the context of phase transitions in physical systems and that is associated with favorable information processing in the context of the brain. The focus of this thesis is to expand upon past results with new experimentation and modeling to show a relationship between criticality and the ability to detect and discriminate sensory input. A line of theoretical work predicts maximal sensory discrimination as a functional benefit of criticality, which can then be characterized using mutual information between sensory input, visual stimulus, and neural response,. The primary finding of our experiments in the visual cortex in turtles and neuronal network modeling confirms this theoretical prediction. We show that sensory discrimination is maximized when visual cortex operates near criticality. In addition to presenting this primary finding in detail, this thesis will also address our preliminary results on change-point-detection in experimentally measured cortical dynamics.

Effects of a Web-Based Antenatal Care System on Maternal Stress and Self-Efficacy During Pregnancy: A Study in Taiwan.

PubMed

Tsai, Yi-Jing; Hsu, Yu-Yun; Hou, Ting-Wei; Chang, Chiung-Hsin

2018-03-01

Women may experience significant stress during pregnancy, and antenatal care and education provide a means to address this. E-health, the use of computer and information technology for health care, has been incorporated into antenatal care and education, but e-health has not been evaluated for its usefulness in addressing stress. The objective of this study was to investigate the effectiveness of a web-based antenatal care and education system on pregnancy-related stress, general self-efficacy, and satisfaction with antenatal care. A quasi-experimental design enrolled pregnant women at 16 to 24 weeks' gestation with a low-risk pregnancy. Women in the control group (n = 67) received routine antenatal care; women in the experimental group (n = 68) also received a web-based antenatal care and education program in the second trimester. Pregnancy stress and general self-efficacy were assessed at study entry and again at 36 to 38 weeks' gestation; satisfaction with care was assessed at the study endpoint. When the pretest scores were controlled, the women in the experimental group reported significantly lower pregnancy-related stress (F  =  12.9, P < .001) and significantly higher self-efficacy (F = 17.61, P < .001) than did the women in the control group. Women in the experimental group reported lower pregnancy-related stress (t = 5.09, P < .001) and a higher general self-efficacy (t = -3.17, P = .001) at posttest compared to pretest. However, the women in the control group reported a lower general self-efficacy at posttest compared to pretest (t = 2.86, P = .006). Women in the experimental group reported significantly higher satisfaction levels with antenatal care than those in the control group. A web-based antenatal care and education system can improve pregnancy-related stress and general self-efficacy among pregnant women. Integrating health care with web-based or internet-based interventions may improve the quality of antenatal care. © 2018 by the American College of Nurse-Midwives.

The Impact of Classroom Performance System-Based Instruction with Peer Instruction upon Student Achievement and Motivation in Eighth Grade Math Students

ERIC Educational Resources Information Center

Allison, Tracy Michelle Hunter

2012-01-01

The researcher employed two designs to address the research question for this particular study. This quasi-experimental non-equivalent control group study compared the math achievement of 92 eighth grade students who received Classroom Performance System (CPS)-based instruction using Peer Instruction (PI) to 76 eighth grade students who received…

Studying the role of wood-decay fungi in calcium cycling on the Penobscot Experimental Forest: a progress report

Treesearch

Walter C. Shortle; Jody Jellison; Kevin T. Smith; Jonathan S. Schilling

2014-01-01

Depletion of essential mineral nutrients from the rooting zone of trees in northern forests may reduce health and productivity. Long-term field investigations coupled with detailed laboratory studies enhance understanding of the biological processes and suggest means to address potential threats. One such investigation by the U.S. Department of Agriculture, Forest...

What Is Mathematical Modelling? Exploring Prospective Teachers' Use of Experiments to Connect Mathematics to the Study of Motion

ERIC Educational Resources Information Center

Carrejo, David J.; Marshall, Jill

2007-01-01

This paper focuses on the construction, development, and use of mathematical models by prospective science and mathematics teachers enrolled in a university physics course. By studying their involvement in an inquiry-based, experimental approach to learning kinematics, we address a fundamental question about the meaning and role of abstraction in…

Comparing the Achievement of Urban Ninth Graders in Schools Using External Vendors for Whole School Reform

ERIC Educational Resources Information Center

Lynch, Virginia N.

2013-01-01

Use of external vendors to implement school reform and address student achievement in urban secondary schools has not been studied. This quasi-experimental longitudinal study focused on changes in student achievement among urban 9th grade students during the 2010-2011 school year. The theoretical framework was the transformational model of using…

Session on coupled atmospheric/chemistry coupled models

NASA Technical Reports Server (NTRS)

Thompson, Anne

1993-01-01

The session on coupled atmospheric/chemistry coupled models is reviewed. Current model limitations, current issues and critical unknowns, and modeling activity are addressed. Specific recommendations and experimental strategies on the following are given: multiscale surface layer - planetary boundary layer - chemical flux measurements; Eulerian budget study; and Langrangian experiment. Nonprecipitating cloud studies, organized convective systems, and aerosols - heterogenous chemistry are also discussed.

Direct experimental visualization of the global Hamiltonian progression of two-dimensional Lagrangian flow topologies from integrable to chaotic state

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baskan, O.; Clercx, H. J. H; Speetjens, M. F. M.

Countless theoretical/numerical studies on transport and mixing in two-dimensional (2D) unsteady flows lean on the assumption that Hamiltonian mechanisms govern the Lagrangian dynamics of passive tracers. However, experimental studies specifically investigating said mechanisms are rare. Moreover, they typically concern local behavior in specific states (usually far away from the integrable state) and generally expose this indirectly by dye visualization. Laboratory experiments explicitly addressing the global Hamiltonian progression of the Lagrangian flow topology entirely from integrable to chaotic state, i.e., the fundamental route to efficient transport by chaotic advection, appear non-existent. This motivates our study on experimental visualization of this progressionmore » by direct measurement of Poincaré sections of passive tracer particles in a representative 2D time-periodic flow. This admits (i) accurate replication of the experimental initial conditions, facilitating true one-to-one comparison of simulated and measured behavior, and (ii) direct experimental investigation of the ensuing Lagrangian dynamics. The analysis reveals a close agreement between computations and observations and thus experimentally validates the full global Hamiltonian progression at a great level of detail.« less

A study of hydrogen diffusion flames using PDF turbulence model

NASA Technical Reports Server (NTRS)

Hsu, Andrew T.

1991-01-01

The application of probability density function (pdf) turbulence models is addressed. For the purpose of accurate prediction of turbulent combustion, an algorithm that combines a conventional computational fluid dynamic (CFD) flow solver with the Monte Carlo simulation of the pdf evolution equation was developed. The algorithm was validated using experimental data for a heated turbulent plane jet. The study of H2-F2 diffusion flames was carried out using this algorithm. Numerical results compared favorably with experimental data. The computations show that the flame center shifts as the equivalence ratio changes, and that for the same equivalence ratio, similarity solutions for flames exist.

A study of hydrogen diffusion flames using PDF turbulence model

NASA Technical Reports Server (NTRS)

Hsu, Andrew T.

1991-01-01

The application of probability density function (pdf) turbulence models is addressed in this work. For the purpose of accurate prediction of turbulent combustion, an algorithm that combines a conventional CFD flow solver with the Monte Carlo simulation of the pdf evolution equation has been developed. The algorithm has been validated using experimental data for a heated turbulent plane jet. The study of H2-F2 diffusion flames has been carried out using this algorithm. Numerical results compared favorably with experimental data. The computuations show that the flame center shifts as the equivalence ratio changes, and that for the same equivalence ratio, similarity solutions for flames exist.

A New Approach for Assessing the Needs of Service Members and Their Families

DTIC Science & Technology

2011-01-01

ADDRESS(ES) 10 . SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for public... 10 Resource Allocation Data... 10 Quasi-Experimental Evaluations of Programs

Atomistic study of nanoprecipitates influence on plasticity and fracture of crystalline metals

NASA Astrophysics Data System (ADS)

Stegailov, Vladimir; Kuksin, Alexey; Norman, Genri; Yanilkin, Alexey

2007-06-01

The recent experimental results [G.I.Kanel et al., 2006] show the essential influence of the nanoprecipitates on spall strength of copper single crystals. In this work we address this issue by the molecular dynamics study. The models under consideration are the EAM systems of Al nanoclusters in the Cu matrix and Cu clusters in the Al matrix. We consider these two cases as the representative examples of nanocluster-matrix difference in shear strength. Three ways of the high strain rate deformation modeling are studied: hydrostatic and uniaxial strain and shock wave loading in the impactor-target model. The preexisting edge dislocation interaction with the precipitate under shear deformation is addressed. The effect of the precipitate size is considered.

Experimental philosophy and the problem of free will.

PubMed

Nichols, Shaun

2011-03-18

Many philosophical problems are rooted in everyday thought, and experimental philosophy uses social scientific techniques to study the psychological underpinnings of such problems. In the case of free will, research suggests that people in a diverse range of cultures reject determinism, but people give conflicting responses on whether determinism would undermine moral responsibility. When presented with abstract questions, people tend to maintain that determinism would undermine responsibility, but when presented with concrete cases of wrongdoing, people tend to say that determinism is consistent with moral responsibility. It remains unclear why people reject determinism and what drives people's conflicted attitudes about responsibility. Experimental philosophy aims to address these issues and thereby illuminate the philosophical problem of free will.

Animal models in translational studies of PTSD.

PubMed

Daskalakis, Nikolaos P; Yehuda, Rachel; Diamond, David M

2013-09-01

Understanding the neurobiological mechanisms of post-traumatic stress disorder (PTSD) is of vital importance for developing biomarkers and more effective pharmacotherapy for this disorder. The design of bidirectional translational studies addressing all facets of PTSD is needed. Animal models of PTSD are needed not only to capture the complexity of PTSD behavioral characteristics, but also to address experimentally the influence of variety of factors which might determine an individual's vulnerability or resilience to trauma, e.g., genetic predisposition, early-life experience and social support. The current review covers recent translational approaches to bridge the gap between human and animal PTSD research and to create a framework for discovery of biomarkers and novel therapeutics. Published by Elsevier Ltd.

Artefactual nanoparticle activation of the inflammasome platform: in vitro evidence with a nano-formed calcium phosphate

PubMed Central

Pele, Laetitia; Haas, Carolin T; Hewitt, Rachel; Faria, Nuno; Brown, Andy; Powell, Jonathan

2015-01-01

Aim To determine whether in vitro experimental conditions dictate cellular activation of the inflammasome by apatitic calcium phosphate nanoparticles. Material & methods The responses of blood-derived primary human cells to in situ-formed apatite were investigated under different experimental conditions to assess the effect of aseptic culture, cell rest and duration of particle exposure. Cell death and particle uptake were assessed, while IL-1β and caspase 1 responses, with and without lipopolysaccharide prestimulation, were evaluated as markers of inflammasome activation. Results Under carefully addressed experimental conditions, apatitic nanoparticles did not induce cell death or engage the inflammasome platform, although both could be triggered through artefacts of experimentation. Conclusion In vitro studies often predict that engineered nanoparticles, such as synthetic apatite, are candidates for inflammasome activation and, hence, are toxic. However, the experimental setting must be very carefully considered as it may promote false-positive outcomes. PMID:24991724

The Effects of a Systematically Designed Online Learning Environment on Preservice Teachers' Professional Knowledge

ERIC Educational Resources Information Center

Evens, Marie; Larmuseau, Charlotte; Dewaele, Katrien; Van Craesbeek, Leen; Elen, Jan; Depaepe, Fien

2017-01-01

This study examines the effects of an online learning environment on preservice teachers' pedagogical content knowledge (PCK), content knowledge (CK) (related to French in primary teacher education), and pedagogical knowledge (PK) in a quasi-experimental design. More specifically, the following research question is addressed: Is a systematically…

Reluctant to Change: Self-Enhancing Responses to Diverging Performance Measures

ERIC Educational Resources Information Center

Audia, Pino G.; Brion, Sebastien

2007-01-01

Although there is extensive evidence that past performance influences the propensity to make changes, research on how decision makers respond to diverging performance measures has been sparse. This paper addresses this gap in an experimental and a field study in which we examine how decision makers respond to the ambiguity introduced by two…

Sequence Matters but How Exactly? A Method for Evaluating Activity Sequences from Data

ERIC Educational Resources Information Center

Doroudi, Shayan; Holstein, Kenneth; Aleven, Vincent; Brunskill, Emma

2016-01-01

How should a wide variety of educational activities be sequenced to maximize student learning? Although some experimental studies have addressed this question, educational data mining methods may be able to evaluate a wider range of possibilities and better handle many simultaneous sequencing constraints. We introduce Sequencing Constraint…

A Pilot Study Using an Online, Experimental, Two-Asset Market.

ERIC Educational Resources Information Center

Lypny, Gregory

2003-01-01

Describes an online, securities market, research tool, called Borsa, to engage students in the exploration of asset pricing in microeconomics courses. Defines Borsa as related database files served on the Internet using a dedicated IP address. Discusses practical considerations in running the market. Offers questions that arise from using the…

Visual-Motor Symbol Production Facilitates Letter Recognition in Young Children

ERIC Educational Resources Information Center

Zemlock, Deborah; Vinci-Booher, Sophia; James, Karin H.

2018-01-01

Previous research has suggested that handwriting letters may be an important exerciser to facilitate early letter understanding. Experimental studies to date, however, have not investigated whether this effect is general to any visual-motor experience or specific to handwriting letters. In the present work, we addressed this issue by testing…

Addressing Clinician-Client Mismatch: A Preliminary Intervention Study with a Bilingual Vietnamese-English Preschooler

ERIC Educational Resources Information Center

Pham, Giang; Kohnert, Kathryn; Mann, Deanine

2011-01-01

Purpose: This project examined receptive vocabulary treatment outcomes in the two languages of a bilingual preschooler with moderate to severe language impairment. Method: A series of single-subject experimental designs was used to compare English-only (EO) and bilingual (BI) approaches to receptive vocabulary treatment. The participant, Nam, was…

The Effect of reduced transmittance window tinting on drivers' ability to detect targets in their rear-view mirrors : final report.

DOT National Transportation Integrated Search

1996-01-01

This study addressed the degree to which motor vehicle window tint films impede drivers' ability to detect targets in their vehicle's rear-view mirrors. Twenty-four subjects participated. Each sat in the driver's seat of one of four experimental vehi...

How Does the Implementation of Discipline-Based Service-Learning Impact High-School and College Students?

ERIC Educational Resources Information Center

Thompson, Michael G.

2012-01-01

Undergraduate science and engineering institutions are currently attempting to improve recruiting practices and to retain engineering majors by addressing what many studies document as the major challenges of poor instruction. Service is described as experimental learning through the integration of traditional classroom teaching with structured…

Does Civic Education Matter?: The Power of Long-Term Observation and the Experimental Method

ERIC Educational Resources Information Center

Claassen, Ryan L.; Monson, J. Quin

2015-01-01

Despite consensus regarding the civic shortcomings of American citizens, no such scholarly consensus exists regarding the effectiveness of civic education addressing political apathy and ignorance. Accordingly, we report the results of a detailed study of students enrolled in introductory American politics courses on the campuses of two large…

The effectiveness of interventions to meet family needs of critically ill patients in an adult intensive care unit: a systematic review.

PubMed

Kynoch, Kate; Chang, Anne M; Coyer, Fiona

Background Attending to the needs of family members of critically ill patients is an important and necessary step in providing appropriate care for both the patient and the family. An initial search of the Cochrane and Joanna Briggs Institute Libraries did not reveal any published systematic reviews recommending effective interventions for addressing family needs of critically ill patients in an acute intensive care unit.Objectives This systematic review aims to establish best practice in addressing the needs of family members with a relative admitted to an adult critical care unit.Search strategy An extensive search of the major databases was conducted. Databases searched included: MEDLINE, CINAHL, psycINFO, Health source, Web of science, EMBASE, the Cochrane library and Database of abstracts of reviews of effects (DARE) as well as Pubmed. The search included published and unpublished studies and papers in English from 1980-2010.Selection criteria This review considered any randomised controlled trials that evaluated the effectiveness of interventions in addressing family needs of critically ill patients in an adult intensive care unit. In the absence of randomised controlled trials, other research designs such as quasi-experimental as well as before and after studies were considered for inclusion in the narrative summary to enable the identification of current approaches and possible future strategies for addressing family needs of critically ill patients.Assessment of quality Each included study was assessed by two independent reviewers using the appropriate appraisal checklist developed by the Joanna Briggs Institute.Data collection and analysis Data was extracted from the papers included in this review using standardised data extraction tools from the Joanna Briggs Institute Meta Analysis of Statistics Assessment and Review Instrument package. The studies included in this review were not suitable for meta-analysis and therefore the results are presented in narrative form.Results Fourteen studies and one dissertation met the inclusion criteria and were included in the review. There were 12 quasi-experimental studies identified including 8 two or three group, pre-test/post-test studies; 1 one-way between subjects design; 1 interrupted time series and 1 two-group comparative design study. The dissertation was a quasi-experimental three group pre-test/post-test design. There were 3 prospective randomised trials included. The evidence identified includes: the use of support groups for family members of patients admitted to an intensive care unit, structured communication and/or education programs for family members, the use of leaflets or brochures to meet family information needs and open or more flexible visiting hours.Conclusion/Recommendations This review makes several recommendations for clinical practice to address family needs of patients admitted to a critical care unit, however this review highlights the need for significant further research in this area. Future intervention studies focusing on family needs could include: the use of technology such as DVD's and SMS for informing families and interventions specifically designed to improve family comfort.

Initial Experimental Airworthiness Certification Guidance for UAS. UAS Experimental Certification Process and Guidance

NASA Technical Reports Server (NTRS)

2005-01-01

This paper addresses the regulatory processes and requirements already in place by which an applicant might obtain experimental airworthiness certification for a civil Unmanned Aircraft System (UAS). It is more extensive and subsequent to an earlier, similar deliverable, PD007, which was an interim study of the same topic. Since few regulatory airworthiness and operating standards exist for UAS like those for traditional manned aircraft and since most UAS have historically been developed and operated under military auspices, civil use of UAS in the NAS is a new and unfamiliar challenge requiring specific and unique considerations. Experimental certification is the most basic level of FAA approval toward routine UAS operation in the NAS. The paper reviews and explains existing FAA requirements for an applicant seeking experimental airworthiness approval and details the process for submission of necessary information. It summarizes the limited purposes for which experimental aircraft may be used and addresses pertinent aspects of UAS design, construction and operation in the NAS in harmony with traditional manned aircraft. Policy IPT position is that UAS, while different from manned aircraft, can use the same initial processes to gain civil operating experience under the experimental approval. Particular note is taken of those UAS-unique characteristics which require extra attention to assure equivalent safety of operation, such as the UAS control station and sense-and-avoid. The paper also provides "best practices" guidance for UAS manufacturers and FAA personnel in two appendices. The material in Appendix A is intended to provide guidance on assuring UAS safety to FAA, and provides FAA personnel with a suggested list of items to review, with a focus on UAS unique factors, prior to issuance of an experimental airworthiness certificate. Appendix B provides an outline for a program letter which a manufacturer could use in preparing the application for an UAS experimental airworthiness certificate.

Flight testing of airbreathing hypersonic vehicles

NASA Technical Reports Server (NTRS)

Hicks, John W.

1993-01-01

Using the scramjet engine as the prime example of a hypersonic airbreathing concept, this paper reviews the history of and addresses the need for hypersonic flight tests. It also describes how such tests can contribute to the development of airbreathing technology. Aspects of captive-carry and free-flight concepts are compared. An incremental flight envelope expansion technique for manned flight vehicles is also described. Such critical issues as required instrumentation technology and proper scaling of experimental devices are addressed. Lastly, examples of international flight test approaches, existing programs, or concepts currently under study, development, or both, are given.

All-optical 10Gb/s ternary-CAM cell for routing look-up table applications.

PubMed

Mourgias-Alexandris, George; Vagionas, Christos; Tsakyridis, Apostolos; Maniotis, Pavlos; Pleros, Nikos

2018-03-19

We experimentally demonstrate the first all-optical Ternary-Content Addressable Memory (T-CAM) cell that operates at 10Gb/s and comprises two monolithically integrated InP Flip-Flops (FF) and a SOA-MZI optical XOR gate. The two FFs are responsible for storing the data bit and the ternary state 'X', respectively, with the XOR gate used for comparing the stored FF-data and the search bit. The experimental results reveal error-free operation at 10Gb/s for both Write and Ternary Content Addressing of the T-CAM cell, indicating that the proposed optical T-CAM cell could in principle lead to all-optical T-CAM-based Address Look-up memory architectures for high-end routing applications.

Student Collaboration in a Series of Integrated Experiments to Study Enzyme Reactor Modeling with Immobilized Cell-Based Invertase

ERIC Educational Resources Information Center

Taipa, M. A^ngela; Azevedo, Ana M.; Grilo, Anto´nio L.; Couto, Pedro T.; Ferreira, Filipe A. G.; Fortuna, Ana R. M.; Pinto, Ine^s F.; Santos, Rafael M.; Santos, Susana B.

2015-01-01

An integrative laboratory study addressing fundamentals of enzyme catalysis and their application to reactors operation and modeling is presented. Invertase, a ß-fructofuranosidase that catalyses the hydrolysis of sucrose, is used as the model enzyme at optimal conditions (pH 4.5 and 45 °C). The experimental work involves 3 h of laboratory time…

The Effect of a Computerized Simulation on Middle School Students' Understanding of the Kinetic Molecular Theory

ERIC Educational Resources Information Center

Stern, Luli; Barnea, Nitza; Shauli, Sofia

2008-01-01

The objective of this study was to evaluate the effect of a dynamic software simulation on the understanding of the kinetic molecular theory by 7th graders. Students in the control group (n = 62) studied a curricular unit that addressed the differences in arrangement and motion of molecules in the three phases of matter. The experimental group (n…

What Difference Does Curricular Integration Make? An Inquiry of Fifth Graders' Learning of History through the Use of Literacy and Visual Arts Skills

ERIC Educational Resources Information Center

Brugar, Kristy A.

2012-01-01

This is a quasi-experimental mixed methods study of a curriculum intervention focused on the interdisciplinary teaching of history, literacy, and the visual arts. In this study I address three questions: (1) How does students' learning in history change following their participation in an interdisciplinary history-literacy-visual arts…

Prevention of the Post-traumatic Fibrotic Response in Joints

DTIC Science & Technology

2014-10-01

an experimental model in mice. The American journal of forensic medicine and pathology . 1988; 9(4):310-2. 14 APPENDICES: An abstract...ongoing study addresses the critical clinical problem of posttraumatic joint stiffness, a pathology that reduces the range of motion (ROM) of injured...joints and contributes to the development of osteoarthritis. The fundamental hypothesis that drives the current study is that pathological fibrotic

Monitoring trends in bird populations: addressing background levels of annual variability in counts

Treesearch

Jared Verner; Kathryn L. Purcell; Jennifer G. Turner

1996-01-01

Point counting has been widely accepted as a method for monitoring trends in bird populations. Using a rigorously standardized protocol at 210 counting stations at the San Joaquin Experimental Range, Madera Co., California, we have been studying sources of variability in point counts of birds. Vegetation types in the study area have not changed during the 11 years of...

Over my fake body: body ownership illusions for studying the multisensory basis of own-body perception

PubMed Central

Kilteni, Konstantina; Maselli, Antonella; Kording, Konrad P.; Slater, Mel

2015-01-01

Which is my body and how do I distinguish it from the bodies of others, or from objects in the surrounding environment? The perception of our own body and more particularly our sense of body ownership is taken for granted. Nevertheless, experimental findings from body ownership illusions (BOIs), show that under specific multisensory conditions, we can experience artificial body parts or fake bodies as our own body parts or body, respectively. The aim of the present paper is to discuss how and why BOIs are induced. We review several experimental findings concerning the spatial, temporal, and semantic principles of crossmodal stimuli that have been applied to induce BOIs. On the basis of these principles, we discuss theoretical approaches concerning the underlying mechanism of BOIs. We propose a conceptualization based on Bayesian causal inference for addressing how our nervous system could infer whether an object belongs to our own body, using multisensory, sensorimotor, and semantic information, and we discuss how this can account for several experimental findings. Finally, we point to neural network models as an implementational framework within which the computational problem behind BOIs could be addressed in the future. PMID:25852524

Predicting evolutionary responses to climate change in the sea.

PubMed

Munday, Philip L; Warner, Robert R; Monro, Keyne; Pandolfi, John M; Marshall, Dustin J

2013-12-01

An increasing number of short-term experimental studies show significant effects of projected ocean warming and ocean acidification on the performance on marine organisms. Yet, it remains unclear if we can reliably predict the impact of climate change on marine populations and ecosystems, because we lack sufficient understanding of the capacity for marine organisms to adapt to rapid climate change. In this review, we emphasise why an evolutionary perspective is crucial to understanding climate change impacts in the sea and examine the approaches that may be useful for addressing this challenge. We first consider what the geological record and present-day analogues of future climate conditions can tell us about the potential for adaptation to climate change. We also examine evidence that phenotypic plasticity may assist marine species to persist in a rapidly changing climate. We then outline the various experimental approaches that can be used to estimate evolutionary potential, focusing on molecular tools, quantitative genetics, and experimental evolution, and we describe the benefits of combining different approaches to gain a deeper understanding of evolutionary potential. Our goal is to provide a platform for future research addressing the evolutionary potential for marine organisms to cope with climate change. © 2013 John Wiley & Sons Ltd/CNRS.

A microgenetic study of learning about the molecular theory of matter and chemical reactions

NASA Astrophysics Data System (ADS)

Chinn, Clark Allen

This paper reports the results of an experimental microgenetic study of children learning complex knowledge from text and experiments. The study had two goals. The first was to investigate fine-grained, moment-to-moment changes in knowledge as middle-school students learned about molecules and chemical reactions over thirteen sessions. The second was to investigate the effects of two instructional treatments, one using implicit textbook explanations and one using explicit explanations developed according to a theory of how scientific knowledge is structured. In the study, 61 sixth- and seventh-graders worked one on one with undergraduate instructors in eleven sessions of about 50 to 80 minutes. The instructors guided the students in conducting experiments and thinking out loud about texts. Topics studied included molecules, states of matter, chemical reactions, and heat transfer. A dense array of questions provided a detailed picture of children's moment-to-moment and day-to-day changes in knowledge. Three results chapters address students' preinstructional knowledge, the effects of the experimental treatment at posttest, and five detailed case studies of students' step-by-step knowledge change over eleven sessions. The chapter on preinstructional knowledge discussed three aspects of global knowledge change: conceptual change, coherence, and entrenchment. Notably, this chapter provides systematic evidence that children's knowledge was fragmented and that consistency with general unifying principles did not guarantee a highly coherent body of knowledge. The experimental manipulation revealed a strong advantage for explicit explanations over implicit textbook explanations. Multiple explicit explanations (e.g., highly explicit explanations of three or four chemical reactions) appeared to be necessary for students to master key concepts. Microgenetic analyses of five cases addressed eight empirical issues that should be addressed by any theory of knowledge acquisition: (a) the nature of the overall knowledge change, (b) the progression of intermediate states during knowledge change, (c) initiators of knowledge change, (d) interactions of prior background knowledge and prior domain knowledge during knowledge changes, (e) the fate of old and new knowledge, (f) the relationship between belief and knowledge, (g) changes in meta-awareness, and (h) factors that influenced the course of knowledge change.

77 FR 69796 - Fisheries of the Exclusive Economic Zone Off Alaska; Application for an Exempted Fishing Permit

Federal Register 2010, 2011, 2012, 2013, 2014

2012-11-21

...-year EFP. The experimental design requires this quantity of salmon to ensure statistically valid... of the groundfish harvested each year from the EFP is expected to be pollock. The experimental design... concentrations of salmon and pollock for addressing experimental design criteria. The activities under the EFP...

The effectiveness of staff training focused on increasing emotional intelligence and improving interaction between support staff and clients.

PubMed

Zijlmans, L J M; Embregts, P J C M; Gerits, L; Bosman, A M T; Derksen, J J L

2015-07-01

Recent research addressed the relationship between staff behaviour and challenging behaviour of individuals with an intellectual disability (ID). Consequently, research on interventions aimed at staff is warranted. The present study focused on the effectiveness of a staff training aimed at emotional intelligence and interactions between staff and clients. The effects of the training on emotional intelligence, coping style and emotions of support staff were investigated. Participants were 214 support staff working within residential settings for individuals with ID and challenging behaviour. The experimental group consisted of 76 staff members, 138 staff members participated in two different control groups. A pre-test, post-test, follow-up control group design was used. Effectiveness was assessed using questionnaires addressing emotional intelligence, coping and emotions. Emotional intelligence of the experimental group changed significantly more than that of the two control groups. The experimental group showed an increase in task-oriented coping, whereas one control group did not. The results with regard to emotions were mixed. Follow-up data revealed that effects within the experimental group were still present four months after the training ended. A staff training aimed at emotional intelligence and staff-client interactions is effective in improving emotional intelligence and coping styles of support staff. However, the need for more research aiming at the relationship between staff characteristics, organisational factors and their mediating role in the effectiveness of staff training is emphasised. © 2014 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

New experimental treatments for core social domain in autism spectrum disorders.

PubMed

Canitano, Roberto

2014-01-01

Current therapeutics in autism spectrum disorders (ASD) only treat the associated symptoms, without addressing core social dysfunctions. A paradigm shift in research of the pathogenesis of ASD, its synaptic abnormalities and altered signaling in multiple dynamic systems, have led to new experimental treatments for treating the core social abnormalities of ASD. NMDA antagonists, especially memantine, have been introduced in clinical trials addressing glutamatergic transmission in children and adolescents with ASD. GABAergic signaling has been targeted in trials using the GABAB receptor agonist arbaclofen for ASD patients with promising results. Oxytocin has been recognized as implicated in social development and affiliative behaviors. Preliminary findings from clinical trials using oxytocin in children with ASD show encouraging improvements in social cognition, but larger studies are needed. In two of the single gene disorders associated with ASD, Insulin Growth Factor (IGF-1) is a new treatment that has been tested in Rett syndrome and Phelan-McDermid syndrome (Chromosome 22 deletion syndrome). IGF-1 has been demonstrated to reverse the reduction in the number of excitatory synapses and the density of neurons that characterize these conditions in animal studies and it is being introduced as an experimental treatment. As a novel approach to verify treatment efficacy, neural processing modifications were recently evaluated by fMRI after a pivotal response training intervention. Another study of neural changes in response to treatment examined variations in EEG signaling in patients after an Early Start Denver Model (ESDM) intervention.

Properties of inductive reasoning.

PubMed

Heit, E

2000-12-01

This paper reviews the main psychological phenomena of inductive reasoning, covering 25 years of experimental and model-based research, in particular addressing four questions. First, what makes a case or event generalizable to other cases? Second, what makes a set of cases generalizable? Third, what makes a property or predicate projectable? Fourth, how do psychological models of induction address these results? The key results in inductive reasoning are outlined, and several recent models, including a new Bayesian account, are evaluated with respect to these results. In addition, future directions for experimental and model-based work are proposed.

Crowdsourcing for Cognitive Science – The Utility of Smartphones

PubMed Central

Brown, Harriet R.; Zeidman, Peter; Smittenaar, Peter; Adams, Rick A.; McNab, Fiona; Rutledge, Robb B.; Dolan, Raymond J.

2014-01-01

By 2015, there will be an estimated two billion smartphone users worldwide. This technology presents exciting opportunities for cognitive science as a medium for rapid, large-scale experimentation and data collection. At present, cost and logistics limit most study populations to small samples, restricting the experimental questions that can be addressed. In this study we investigated whether the mass collection of experimental data using smartphone technology is valid, given the variability of data collection outside of a laboratory setting. We presented four classic experimental paradigms as short games, available as a free app and over the first month 20,800 users submitted data. We found that the large sample size vastly outweighed the noise inherent in collecting data outside a controlled laboratory setting, and show that for all four games canonical results were reproduced. For the first time, we provide experimental validation for the use of smartphones for data collection in cognitive science, which can lead to the collection of richer data sets and a significant cost reduction as well as provide an opportunity for efficient phenotypic screening of large populations. PMID:25025865

Crowdsourcing for cognitive science--the utility of smartphones.

PubMed

Brown, Harriet R; Zeidman, Peter; Smittenaar, Peter; Adams, Rick A; McNab, Fiona; Rutledge, Robb B; Dolan, Raymond J

2014-01-01

By 2015, there will be an estimated two billion smartphone users worldwide. This technology presents exciting opportunities for cognitive science as a medium for rapid, large-scale experimentation and data collection. At present, cost and logistics limit most study populations to small samples, restricting the experimental questions that can be addressed. In this study we investigated whether the mass collection of experimental data using smartphone technology is valid, given the variability of data collection outside of a laboratory setting. We presented four classic experimental paradigms as short games, available as a free app and over the first month 20,800 users submitted data. We found that the large sample size vastly outweighed the noise inherent in collecting data outside a controlled laboratory setting, and show that for all four games canonical results were reproduced. For the first time, we provide experimental validation for the use of smartphones for data collection in cognitive science, which can lead to the collection of richer data sets and a significant cost reduction as well as provide an opportunity for efficient phenotypic screening of large populations.

An Interactive Computer-Aided Instructional Strategy and Assessment Methods for System Identification and Adaptive Control Laboratory

ERIC Educational Resources Information Center

Özbek, Necdet Sinan; Eker, Ilyas

2015-01-01

This study describes a set of real-time interactive experiments that address system identification and model reference adaptive control (MRAC) techniques. In constructing laboratory experiments that contribute to efficient teaching, experimental design and instructional strategy are crucial, but a process for doing this has yet to be defined. This…

Operational experiments for sustainably managing forests (Grossflächige Feldversuche für die nachhaltige Waldnutzung).

Treesearch

Robert C. Szaro; Charles E. Peterson; Klaus Von Gadow

2006-01-01

Historically, applied manipulative studies of forests have tested the ability of specific silvicultural treatments to address wood production objectives. Changing societal values now demand expanded approaches to forest management that also integrate social, ecological, and economic goals. As a result, many recent (past decade) experimental manipulations have become...

The Effects of Corrective Feedback on Instructed L2 Speech Perception

ERIC Educational Resources Information Center

Lee, Andrew H.; Lyster, Roy

2016-01-01

To what extent do second language (L2) learners benefit from instruction that includes corrective feedback (CF) on L2 speech perception? This article addresses this question by reporting the results of a classroom-based experimental study conducted with 32 young adult Korean learners of English. An instruction-only group and an instruction + CF…

Addressing the Needs of Students with Learning Disabilities during Their Interaction with the Web

ERIC Educational Resources Information Center

Curcic, Svjetlana

2011-01-01

Purpose: The purpose of this study is to examine the effectiveness of instruction in information problem solving within the world wide web (the web) environment. The participants were 20 seventh and eighth grade students with a learning disability (LD) in reading. An experimental pretest-posttest control group method was used to investigate the…

Joven Noble: Evaluation of a Culturally Focused Youth Development Program

ERIC Educational Resources Information Center

Tello, Jerry; Cervantes, Richard C.; Cordova, David; Santos, Susana M.

2010-01-01

The purpose of this study was to describe and evaluate a promising program model, the Joven Nobel curriculum, for Latino male adolescents that promotes positive youth development and addresses prevention of a number of risk-related sexual behaviors within a cultural context. A quasi-experimental design was used that included a pre- and posttest…

Windows into the forest: extending long-term small-watershed research

Treesearch

Sally Duncan

2004-01-01

Interactions among forests, forestry, and water remain a critical aspect of Forest Service land stewardship. Small, experimental watershed studies managed by Forest Service Research and Development have a long history of advancing science and management and have resulted in a rich collection of long-term data. Early work addressed effects of forestry practices in...

Physics Learning with a Computer Algebra System: Towards a Learning Environment That Promotes Enhanced Problem Representations.

ERIC Educational Resources Information Center

Savelsbergh, Elwin R.; Ferguson-Hessler, Monica G. M.; de Jong, Ton

An approach to teaching problem-solving based on using the computer software Mathematica is applied to the study of electrostatics and is compared with the normal approach to the module. Learning outcomes for both approaches were not significantly different. The experimental course successfully addressed a number of misconceptions. Students in the…

Field experimental design comparisons to detect field effects associated with agronomic traits in Upland cotton

USDA-ARS?s Scientific Manuscript database

Field variation is one of the important factors that can have a significant impact on genetic data analysis. Ineffective control of field variation may result in an inflated residual variance and/or biased estimation of genetic variations and/or effects. In this study, we addressed this problem by m...

Long-term sedimentation effects of different patterns of timber harvesting

Treesearch

R. R. Ziemer; J. Lewis; T. E. Lisle; Rice. R. M.

1991-01-01

Abstract - It is impractical to address the long-term effect of forest management strategies on erosion, sedimentation, and the resultant damage to fish habitat experimentally because to do so would require studying large watersheds for a century or more. Monte Carlo simulations were conducted on three hypothetical 10 000 ha, fifth-order forested watersheds. One...

The Effects of Differentiated Foreign Language Instruction on Academic Achievement and Creativity of Gifted Students

ERIC Educational Resources Information Center

Aysin, Sayi K.; Serap, Emir

2017-01-01

The main aim of this study is to investigate the effects of an English language education program that addresses the academic and cognitive needs of gifted children on their academic achievement and creative thinking levels. To this end, through an experimental research design, the unit "Health Problems" in English course book was…

Immersing Undergraduate Students in the Research Experience: A Practical Laboratory Module on Molecular Cloning of Microbial Genes

ERIC Educational Resources Information Center

Wang, Jack T. H.; Schembri, Mark A.; Ramakrishna, Mathitha; Sagulenko, Evgeny; Fuerst, John A.

2012-01-01

Molecular cloning skills are an essential component of biological research, yet students often do not receive this training during their undergraduate studies. This can be attributed to the complexities of the cloning process, which may require many weeks of progressive design and experimentation. To address this issue, we incorporated an…

The Newest "Reality Show": The Importance of Legitimizing Experimental Learning with Community-Based Research

ERIC Educational Resources Information Center

Johnson, Matthew D.

2004-01-01

The study describes how most current biological curricula fail to foster citizenry, how this failure is problematic for conservation, and offers one approach to address the problem. Local city planners and state Department of Fish and Game have proposed a marsh restoration project near the university to compare and contrast how wildlife would…

Women in Academic Science: Experimental Findings from Hiring Studies

ERIC Educational Resources Information Center

Ceci, Stephen J.

2018-01-01

Although women are underrepresented in the most mathematically intensive fields, the gender gap in these fields has narrowed over the past 2 decades. In my E. L. Thorndike address I summarized the temporal trends in sex differences for 8 fields and considered factors that drive both the underrepresentation of women and its recent narrowing. I…

Neighborhoods of Words in the Mental Lexicon. Research on Speech Perception. Technical Report No. 6.

ERIC Educational Resources Information Center

Luce, Paul A.

A study employed computational and experimental methods to address a number of issues related to the representation and structural organization of spoken words in the mental lexicon. Using a computerized lexicon consisting of phonetic transcriptions of 20,000 words, "similarity neighborhoods" for each of the transcriptions were computed.…

Modeling the cumulative watershed effects of forest management strategies

Treesearch

R. R. Ziemer; J. Lewis; R. M. Rice; T. E. Lisle

1991-01-01

Abstract - There is increasing concern over the possibility of adverse cumulative watershed effects from intensive forest management. It is impractical to address many aspects of the problem experimentally because to do so would require studying large watersheds for 100 yr or more. One such aspect is the long-term effect of forest management strategies on erosion and...

The First Line of Defense: Training Teachers to Address Bullying in Rural Schools

ERIC Educational Resources Information Center

Townsend, LaSonya C.

2013-01-01

This action research study investigated teachers' perception of bullying and bullying training. It also examined the effects the Bully Busters training had on the bullying knowledge, skills, and self-efficacy of teachers and teacher assistants. A mixed method approach, which included a pre-experimental design and interviews were used to collect…

Brief Report: Generalization Weaknesses in Verbally Fluent Children and Adolescents with Autism Spectrum Disorder

ERIC Educational Resources Information Center

de Marchena, Ashley B.; Eigsti, Inge-Marie; Yerys, Benjamin E.

2015-01-01

Individuals with autism spectrum disorder (ASD) have difficulty generalizing--i.e., relating new stimuli to past experiences. Few experimental studies have addressed this weakness, despite its impact on intervention effects. In a reanalysis of data (de Marchena et al. "Cognition" 119(1):96-113, 2011), we tested a novel form of…

Evaluating long-term cumulative hydrologic effects of forest management: a conceptual approach

Treesearch

Robert R. Ziemer

1992-01-01

It is impractical to address experimentally many aspects of cumulative hydrologic effects, since to do so would require studying large watersheds for a century or more. Monte Carlo simulations were conducted using three hypothetical 10,000-ha fifth-order forested watersheds. Most of the physical processes expressed by the model are transferable from temperate to...

Myths and legends in learning classification rules

NASA Technical Reports Server (NTRS)

Buntine, Wray

1990-01-01

A discussion is presented of machine learning theory on empirically learning classification rules. Six myths are proposed in the machine learning community that address issues of bias, learning as search, computational learning theory, Occam's razor, universal learning algorithms, and interactive learning. Some of the problems raised are also addressed from a Bayesian perspective. Questions are suggested that machine learning researchers should be addressing both theoretically and experimentally.

Mechanical Behaviour of 3D Multi-layer Braided Composites: Experimental, Numerical and Theoretical Study

NASA Astrophysics Data System (ADS)

Deng, Jian; Zhou, Guangming; Ji, Le; Wang, Xiaopei

2017-12-01

Mechanical properties and failure mechanisms of a newly designed 3D multi-layer braided composites are evaluated by experimental, numerical and theoretical studies. The microstructure of the composites is introduced. The unit cell technique is employed to address the periodic arrangement of the structure. The volume averaging method is used in theoretical solutions while FEM with reasonable periodic boundary conditions and meshing technique in numerical simulations. Experimental studies are also conducted to verify the feasibility of the proposed models. Predicted elastic properties agree well with the experimental data, indicating the feasibility of the proposed models. Numerical evaluation is more accurate than theoretical assessment. Deformations and stress distributions of the unit cell under tension shows displacement and traction continuity, guaranteeing the rationality of the applied periodic boundary conditions. Although compression and tension modulus are close, the compressive strength only reaches 70% of the tension strength. This indicates that the composites can be weakened in compressive loading. Additionally, by analysing the micrograph of fracture faces and strain-stress curves, a brittle failure mechanism is observed both in composites under tension and compression.

Experimental Research on Dreaming: State of the Art and Neuropsychoanalytic Perspectives

PubMed Central

Ruby, Perrine M.

2011-01-01

Dreaming is still a mystery of human cognition, although it has been studied experimentally for more than a century. Experimental psychology first investigated dream content and frequency. The neuroscientific approach to dreaming arose at the end of the 1950s and soon proposed a physiological substrate of dreaming: rapid eye movement sleep. Fifty years later, this hypothesis was challenged because it could not explain all of the characteristics of dream reports. Therefore, the neurophysiological correlates of dreaming are still unclear, and many questions remain unresolved. Do the representations that constitute the dream emerge randomly from the brain, or do they surface according to certain parameters? Is the organization of the dream’s representations chaotic or is it determined by rules? Does dreaming have a meaning? What is/are the function(s) of dreaming? Psychoanalysis provides hypotheses to address these questions. Until now, these hypotheses have received minimal attention in cognitive neuroscience, but the recent development of neuropsychoanalysis brings new hopes of interaction between the two fields. Considering the psychoanalytical perspective in cognitive neuroscience would provide new directions and leads for dream research and would help to achieve a comprehensive understanding of dreaming. Notably, several subjective issues at the core of the psychoanalytic approach, such as the concept of personal meaning, the concept of unconscious episodic memory and the subject’s history, are not addressed or considered in cognitive neuroscience. This paper argues that the focus on singularity and personal meaning in psychoanalysis is needed to successfully address these issues in cognitive neuroscience and to progress in the understanding of dreaming and the psyche. PMID:22121353

Innovative Approaches to Treating Type 1 Diabetes Addressed in Beta-Cell Replacement Presentations

MedlinePlus

... ability to detect hypoglycemia. It is still considered experimental, however, and, due to a shortage of donors, ... into his or her own body, is another experimental approach for treating degenerative diseases including diabetes. Chad ...

Where and How Does Grammatically Geared Processing Take Place--And Why Is Broca's Area Often Involved. A Coordinated fMRI/ERBP Study of Language Processing

ERIC Educational Resources Information Center

Dogil, Grzegorz; Frese, Inga; Haider, Hubert; Rohm, Dietmar; Wokurek, Wolfgang

2004-01-01

We address the possibility of combining the results from hemodynamic and electrophysiological methods for the study of cognitive processing of language. The hemodynamic method we use is Event-Related fMRI, and the electrophysiological method measures Event-Related Band Power (ERBP) of the EEG signal. The experimental technique allows us to…

Prevention of the Post-traumatic Fibrotic Response in Joints

DTIC Science & Technology

2014-10-01

JJ, Wolman M. Aging of wound healing in an experimental model in mice. The American journal of forensic medicine and pathology . 1988; 9(4):310-2...SUPPLEMENTARY NOTES 14. ABSTRACT The ongoing study addresses the critical clinical problem of posttraumatic joint stiffness, a pathology that reduces...study is that pathological fibrotic response of injured joint tissues may be limited by targeting the formation of collagen fibrils, a main component

Effects of prescribed fire on the wood quality and marketability of four hardwood species in the central Appalachian region

Treesearch

Janice K. Wiedenbeck; Thomas M. Schuler

2014-01-01

A series of research studies addressing the effect of prescribed fire on oak (Quercus spp.) regeneration has been ongoing on the Fernow Experimental Forest in northeastern West Virginia for 10 years. The study site is a mesic, mixed oak forest. Two prescribed fires were conducted in spring 2002 and 2005. In 2010, a shelterwood harvest was conducted....

FT-IR spectroscopic studies of polycyclic aromatic hydrocarbons

NASA Technical Reports Server (NTRS)

Salisbury, D. W.; Allen, J. E., Jr.; Donn, B.; Moore, W. J.; Khanna, R. K.

1990-01-01

Proper assessment of the hypothesis which correlates polycyclic aromatic hydrocarbons (PAHs) with the unidentified infrared emission bands requires additional experimental laboratory data. In order to address this need, thermal infrared emission studies were performed on a subset of PAHs suggested to be of astrophysical importance. It was proposed that infrared emission from interstellar PAHs occurs following absorption of an ultraviolet photon. Since energy transfer to the ground electronic state can be rapid for a species in which intersystem crossing is negligible, the emission spectrum may be viewed as resulting from an equilibrium vibrational temperature (Leger and d'Hendecourt, 1987). This has been the basis for using infrared absorption spectra to calculate the corresponding emission spectra at various temperatures. These calculations were made using room temperature infrared absorption coefficients instead of those at the temperature of interest because of the latter's unavailability. The present studies are designed to address the differences between the calculated and experimental thermal emission spectra and to provide information which will be useful in future ultraviolet induced infrared fluorescence studies. The emission spectra have been obtained for temperatures up to 825K using an emission cell designed to mount against an external port of an FT-IR spectrometer. These spectra provide information concerning relative band intensities and peak positions which is unavailable from previous calculations.

Cellular signaling identifiability analysis: a case study.

PubMed

Roper, Ryan T; Pia Saccomani, Maria; Vicini, Paolo

2010-05-21

Two primary purposes for mathematical modeling in cell biology are (1) simulation for making predictions of experimental outcomes and (2) parameter estimation for drawing inferences from experimental data about unobserved aspects of biological systems. While the former purpose has become common in the biological sciences, the latter is less common, particularly when studying cellular and subcellular phenomena such as signaling-the focus of the current study. Data are difficult to obtain at this level. Therefore, even models of only modest complexity can contain parameters for which the available data are insufficient for estimation. In the present study, we use a set of published cellular signaling models to address issues related to global parameter identifiability. That is, we address the following question: assuming known time courses for some model variables, which parameters is it theoretically impossible to estimate, even with continuous, noise-free data? Following an introduction to this problem and its relevance, we perform a full identifiability analysis on a set of cellular signaling models using DAISY (Differential Algebra for the Identifiability of SYstems). We use our analysis to bring to light important issues related to parameter identifiability in ordinary differential equation (ODE) models. We contend that this is, as of yet, an under-appreciated issue in biological modeling and, more particularly, cell biology. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Advanced Analytic Cognition: Thinking Dispositions

DTIC Science & Technology

2013-09-01

on this instrument showed no significant differences between the experimental and control groups . Further, posttest means were not significantly...different from pretest means in either group ( Pretest : Experimental M = 296, Control M = 297; Posttest : Experimental M = 298, Control M = 302). It...for critical thinking in nursing also addressed thinking dispositions.  The planning group on critical thinking at Frostburg State University

Some Dimensions of Auditory Sonar Signal Perception and Their Relationships to Target Classification

DTIC Science & Technology

1981-02-13

a priori how the sample of experimental stimuli related to the classification stereotypes of experienced sonar personnel, Question 6 was addressed by...projections on some of the experimentally identified dimensions are associ- ated with a high degree of classification success, but signals that lack ,strong...11 Hypotheses ......................... 11 Procedure ....... .. .. ......................... 11 Experimental Stimuli

Determining potential 30/20 GHZ domestic satellite system concepts and establishment of a suitable experimental configuration

NASA Technical Reports Server (NTRS)

Stevens, G. H.; Anzic, G.

1979-01-01

NASA is conducting a series of millimeter wave satellite communication systems and market studies to: (1) determine potential domestic 30/20 GHz satellite concepts and market potential, and (2) establish the requirements for a suitable technology verification payload which, although intended to be modest in capacity, would sufficiently demonstrate key technologies and experimentally address key operational issues. Preliminary results and critical issues of the current contracted effort are described. Also included is a description of a NASA-developed multibeam satellite payload configuration which may be representative of concepts utilized in a technology flight verification program.

FASEB (Federation of American Societies for Experimental Biology) Summer Research on Neuronal Cell Cultures at Saxton’s River, Vermont on 12-17 August 1984.

DTIC Science & Technology

1984-08-17

AD-i5 81@ FASEB (FEDERATION OF AMERICAN SOCIETIES FOR EXPERIMENTAL BIOLOGY ) SUMMER..CU) FEDERATION OF AMERICAN SOCIETIES FOR EXPERIMENTAL BIOLOGY BET...UNIT NUMBERS Robert W. Krauss, Executive Director I * LEO Federation of American Societies for Experimental, NR 685-003 * Biology , 9650 Rockville Pike...Bethesda, MD 20814 *.CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE ’%Federation f American Societies for I Experimental Biology , 9650

Early integration of the individual student in academic activities: a novel classroom concept for graduate education in molecular biophysics and structural biology

PubMed Central

2014-01-01

Background A key challenge in interdisciplinary research is choosing the best approach from a large number of techniques derived from different disciplines and their interfaces. Results To address this challenge in the area of Biophysics and Structural Biology, we have designed a graduate level course to teach students insightful use of experimental biophysical approaches in relationship to addressing biological questions related to biomolecular interactions and dynamics. A weekly seminar and data and literature club are used to compliment the training in class. The course contains wet-laboratory experimental demonstration and real-data analysis as well as lectures, grant proposal preparation and assessment, and student presentation components. Active student participation is mandatory in all aspects of the class. Students prepare materials for the class receiving individual and iterative feedback from course directors and local experts generating high quality classroom presentations. Conclusions The ultimate goal of the course is to teach students the skills needed to weigh different experimental approaches against each other in addressing a specific biological question by thinking and executing academic tasks like faculty. PMID:25132964

Early integration of the individual student in academic activities: a novel classroom concept for graduate education in molecular biophysics and structural biology.

PubMed

Leuba, Sanford H; Carney, Sean M; Dahlburg, Elizabeth M; Eells, Rebecca J; Ghodke, Harshad; Yanamala, Naveena; Schauer, Grant; Klein-Seetharaman, Judith

2014-01-01

A key challenge in interdisciplinary research is choosing the best approach from a large number of techniques derived from different disciplines and their interfaces. To address this challenge in the area of Biophysics and Structural Biology, we have designed a graduate level course to teach students insightful use of experimental biophysical approaches in relationship to addressing biological questions related to biomolecular interactions and dynamics. A weekly seminar and data and literature club are used to compliment the training in class. The course contains wet-laboratory experimental demonstration and real-data analysis as well as lectures, grant proposal preparation and assessment, and student presentation components. Active student participation is mandatory in all aspects of the class. Students prepare materials for the class receiving individual and iterative feedback from course directors and local experts generating high quality classroom presentations. The ultimate goal of the course is to teach students the skills needed to weigh different experimental approaches against each other in addressing a specific biological question by thinking and executing academic tasks like faculty.

Exploring science teachers' perceptions of experimentation: implications for restructuring school practical work

NASA Astrophysics Data System (ADS)

Wei, Bing; Li, Xiaoxiao

2017-09-01

It is commonly recognised that practical work has a distinctive and central role in science teaching and learning. Although a large number of studies have addressed the definitions, typologies, and purposes of practical work, few have consulted practicing science teachers. This study explored science teachers' perceptions of experimentation for the purpose of restructuring school practical work in view of science practice. Qualitative interviews were conducted with 87 science teachers at the secondary school level. In the interviews, science teachers were asked to make a comparison between students' experiments and scientific experiments. Eight dimensions of experimentation were generated from the qualitative data analysis, and the distributions of these eight dimensions between the two types of experiments were compared and analysed. An ideal model of practical work was suggested for restructuring practical work at the secondary school level, and some issues related to the effective enactment of practical work were discussed.

Novel method to dynamically load cells in 3D-hydrogels culture for blast injury studies

NASA Astrophysics Data System (ADS)

Sory, David R.; Areias, Anabela C.; Overby, Darryl R.; Proud, William G.

2017-01-01

For at least a century explosive devices have been one of the most important causes of injuries in military conflicts as well as in terrorist attacks. Although significant experimental and modelling efforts have been focussed on blast injuries at the organ or tissue level, few studies have investigated the mechanisms of blast injuries at the cellular level. This paper introduces an in vitro method compatible with living cells to examine the effects of high stress and short-duration pulses relevant to blast loadings and blunt trauma. The experimental phase involves high strain-rate axial compression of cylindrical specimens within an hermetically sealed chamber made of biocompatible polymer. Numerical simulations were performed in order to verify the experimental loading conditions and to characterize the loading path within the sample. A proof of concept is presented so as to establish a new window to address fundamental questions regarding blast injury at the cellular level.

Planet Formation

NASA Astrophysics Data System (ADS)

Klahr, Hubert; Brandner, Wolfgang

2006-05-01

This volume addresses fundamental questions concerning the formation of planetary systems in general, and of our solar system in particular. Drawing from recent advances in observational, experimental, and theoretical research, it summarises our current understanding of the planet formation processes, and addresses major open questions and research issues. Chapters are written by leading experts in the field of planet formation and extrasolar planet studies. The book is based on a meeting held at Ringberg Castle in Bavaria, where experts gathered together to present and exchange their ideas and findings. It is a comprehensive resource for graduate students and researchers, and is written to be accessible to newcomers to the field.

The relation between statistical power and inference in fMRI

PubMed Central

Wager, Tor D.; Yarkoni, Tal

2017-01-01

Statistically underpowered studies can result in experimental failure even when all other experimental considerations have been addressed impeccably. In fMRI the combination of a large number of dependent variables, a relatively small number of observations (subjects), and a need to correct for multiple comparisons can decrease statistical power dramatically. This problem has been clearly addressed yet remains controversial—especially in regards to the expected effect sizes in fMRI, and especially for between-subjects effects such as group comparisons and brain-behavior correlations. We aimed to clarify the power problem by considering and contrasting two simulated scenarios of such possible brain-behavior correlations: weak diffuse effects and strong localized effects. Sampling from these scenarios shows that, particularly in the weak diffuse scenario, common sample sizes (n = 20–30) display extremely low statistical power, poorly represent the actual effects in the full sample, and show large variation on subsequent replications. Empirical data from the Human Connectome Project resembles the weak diffuse scenario much more than the localized strong scenario, which underscores the extent of the power problem for many studies. Possible solutions to the power problem include increasing the sample size, using less stringent thresholds, or focusing on a region-of-interest. However, these approaches are not always feasible and some have major drawbacks. The most prominent solutions that may help address the power problem include model-based (multivariate) prediction methods and meta-analyses with related synthesis-oriented approaches. PMID:29155843

Myths and legends in learning classification rules

NASA Technical Reports Server (NTRS)

Buntine, Wray

1990-01-01

This paper is a discussion of machine learning theory on empirically learning classification rules. The paper proposes six myths in the machine learning community that address issues of bias, learning as search, computational learning theory, Occam's razor, 'universal' learning algorithms, and interactive learnings. Some of the problems raised are also addressed from a Bayesian perspective. The paper concludes by suggesting questions that machine learning researchers should be addressing both theoretically and experimentally.

On the Experimental Determination of the One-Way Speed of Light

ERIC Educational Resources Information Center

Perez, Israel

2011-01-01

In this paper the question of the isotropy of the one-way speed of light is addressed from an experimental perspective. In particular, we analyse two experimental methods commonly used in its determination. The analysis is aimed at clarifying the view that the one-way speed of light cannot be determined by techniques in which physical entities…

Experimental palaeobiomechanics: What can engineering tell us about evolution in deep time?

NASA Astrophysics Data System (ADS)

Anderson, Philip

2016-04-01

What did Tyrannosaurus rex eat? This is the sort of question that immediately bombards any palaeontologist when interacting with the general public. Even among scientists, how extinct animals moved or fed is a major objective of the palaeobiological research agenda. The last decade has seen a sharp increase in the technology and experimental methods available for collecting biomechanical data, which has greatly improved out ability to examine the function of both live and extinct animals. With new technologies and methods come new pitfalls and opportunities. In this review, I address three aspects of experimental biomechanics that exemplify the challenges and opportunities it provides for addressing deep-time problems in palaeontology. 1) Interpretation: It has never been easier to acquire large amounts of high-quality biomechanical data on extinct animals. However, the lack of behavioural information means that interpreting this data can be problematic. We will never know precisely what a dinosaur ate, but we can explore what constraints there might have been on the mechanical function of its jaws. Palaeobiomechanics defines potential function and becomes especially effective when dealing with multiple examples. 2) Comparison: Understanding the potential function of one extinct animal is interesting; however, examining mechanical features across multiple taxa allows for a greater understanding of biomechanical variation. Comparative studies help identify common trends and underlying mechanical principles which can have long reaching influences on morphological evolution. 3) Evolution: The physical principles established through comparative biomechanical studies can be utilized in phylogenetic comparative methods in order to explore evolutionary morphology across clades. Comparative evolutionary biomechanics offers potential for exploring the evolution of functional systems in deep time utilizing experimental biomechanical data.

Assessing and Improving L2 Graduate Students' Popular Science and Academic Writing in an Academic Writing Course

ERIC Educational Resources Information Center

Rakedzon, Tzipora; Baram-Tsabari, Ayelet

2017-01-01

This paper reports a study using a quasi-experimental design to examine whether an academic writing course in English can improve graduate students' academic and popular science writing skills. To address this issue, we designed pre- and post-assessment tasks, an intervention assessment task and a scoring rubric. The pre- and post-assessment tasks…

Effect of a Performing Arts Program on the Oral Language Skills of Young English Learners

ERIC Educational Resources Information Center

Greenfader, Christa Mulker; Brouillette, Liane; Farkas, George

2015-01-01

Although English oral language proficiency in the primary grades is critical to the literacy development of English learners (ELs), we know little about how to foster these skills. This study examined a yearlong K-2 drama and creative movement intervention. A randomized experimental design (N = 5,240) was used to address two research questions:…

Computer Response Time Measurements of Mood, Fatigue and Symptom Scale Items: Implications for Scale Response Time Uses.

ERIC Educational Resources Information Center

Ryman, David H.; And Others

1988-01-01

Describes study conducted with U.S. Marine Corps enlisted personnel to measure response time to computer-administered questionnaire items, and to evaluate how measurement of response time might be useful in various research areas. Topics addressed include mood states; the occurrence of straight lining; and experimental effects of sleep loss and…

The utility of Geographical Information Systems (GIS) in systems-oriented obesity intervention projects: The selection of comparable study sites for a quasi-experimental intervention design--TX CORD

USDA-ARS?s Scientific Manuscript database

The Texas Childhood Obesity Research Demonstration project (TX CORD) uses a systems-oriented approach to address obesity that includes individual and family interventions, community-level action, as well as environmental and policy initiatives. Given that randomization is seldom possible in communit...

Seven Experiment Designs Addressing Problems of Safety and Capacity on Two-Lane Rural Highways : Volume 7. Experimental Design to Develop and Evaluate Measures for Reducing the Effects of Roadside Friction on Traffic Flow

DOT National Transportation Integrated Search

1994-04-01

This operational test case study is one of six performed in response to a Volpe National Transportation Systems Center technical task directive (TTD) to Science Applications International Corporation (SAIC) entitled, "IVHS Institutional Issues and Ca...

Seven Experiment Designs Addressing Problems of Safety and Capacity on Two-Lane Rural Highways : Volume 4. Experimental Design to Develop and Evaluate Remedial Aids to Urban Drivers of Slow Moving Vehicles on a Grade

DOT National Transportation Integrated Search

1994-04-01

This operational test case study is one of six performed in response to a Volpe National Transportation Systems Center technical task directive (TTD) to Science Applications International Corporation (SAIC) entitled, IVHS Institutional Issues and ...

Impact of a Ninth-Grade Transition Program on Cumulative GPAs and Credits, Ninth-Grade Dropout Rates, and Student Satisfaction

ERIC Educational Resources Information Center

Buhrman, B. R.

2010-01-01

Concerned educators have been implementing ninth-grade transition programs to help freshmen adjust to the demands in high school and to reduce ninth-grade failure rates. The purpose of this quasi-experimental quantitative study was to investigate the impact of a ninth-grade transition program. The research questions addressed impact on cumulative…

The Effects of a School-Based Psychosocial Intervention on Resilience and Health Outcomes among Vulnerable Children

ERIC Educational Resources Information Center

Olowokere, A. E.; Okanlawon, F. A.

2014-01-01

Responding to the psychosocial health needs of the vulnerable population has been considered as a significant public health issue that must be addressed through access to public health professionals. The study adopted a quasi-experimental design to evaluate the impact of a training program on nurses and teachers' knowledge of psychosocial health…

Data Safety Monitoring Boards and Other Study Methodologies that Address Subject Safety in "High-Risk" Therapeutic Trials in Youths

ERIC Educational Resources Information Center

Carandang, Carlo; Santor, Darcy; Gardner, David M.; Carrey, Normand; Kutcher, Stan

2007-01-01

The underlying proposition for any experimental/therapeutic trial is the uncertainty that the risks of treatment will be outweighed by its benefits. For some therapeutic interventions (e.g., exercise programs, vitamin supplementation), the potential for treatment-emergent adverse events may prima facie be low or negligible, whereas for others…

The Online Consumer: An Examination of Gender, Age, Income and Education as Determinants of Online Repurchasing

ERIC Educational Resources Information Center

Portillo, Carol D.

2017-01-01

Online purchasing has increased dramatically over the past 10 years and the pace is expected to continue to accelerate. This new channel of purchasing poses a challenge to online retailers as they strive to increase online repurchasing behavior. This non-experimental study addresses the problem of how to support a rapidly growing online…

The Role of Goal-Directed Behavior in Intention Attribution in Children

ERIC Educational Resources Information Center

Legrain, Laure; Destrebecqz, Arnaud; Gevers, Wim

2012-01-01

In this study, we addressed the question of the nature of the information needed by 13-month-old infants to understand another agent's intentions. In two experiments, an experimenter was either unable or unwilling to give a toy to an infant. Importantly, an implement (a gutter in which the toy could roll down toward the infant) was used to make…

Using instant messaging for Internet-based interviews.

PubMed

Stieger, Stefan; Göritz, Anja S

2006-10-01

One method of data collection that has rarely been applied online is the one-on-one interview. Because of its widespread use, the Internet-based service instant messaging (IM) seems to be suitable to conduct scientific online interviews. A unique benefit of IM is the existence of public address books. These can be used both as a sampling frame and as a cross-reference to validate respondents' demographic data. The feasibility of IM interviews was examined in a WWW survey as well as in actual IM interviews that were combined with an experimental manipulation of the request for participation. On the basis of self-reports, respondent behavior, and data in the address books, the studies have demonstrated that the risk of receiving false data in IM interviews is small. Not only is the quality of the obtainable data satisfying but the contact rate, response rate, and retention rate as well. Moreover, the experimental test demonstrated that the response rate is influenced by the information provided in the chat request. On the basis of the study results, recommendations are given as to when and how IM interviews should be used as a data collection method.

Applications of Augmented Reality-Based Natural Interactive Learning in Magnetic Field Instruction

ERIC Educational Resources Information Center

Cai, Su; Chiang, Feng-Kuang; Sun, Yuchen; Lin, Chenglong; Lee, Joey J.

2017-01-01

Educators must address several challenges inherent to the instruction of scientific disciplines such as physics -- expensive or insufficient laboratory equipment, equipment error, difficulty in simulating certain experimental conditions. Augmented reality (AR) can be a promising approach to address these challenges. In this paper, we discuss the…

26 CFR 1.174-3 - Treatment as expenses.

Code of Federal Regulations, 2011 CFR

2011-04-01

... which he pays or incurs research or experimental expenditures. The taxpayer may do so by claiming in his... addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The request shall... shall be addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The...

26 CFR 1.174-3 - Treatment as expenses.

Code of Federal Regulations, 2013 CFR

2013-04-01

... which he pays or incurs research or experimental expenditures. The taxpayer may do so by claiming in his... addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The request shall... shall be addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The...

26 CFR 1.174-3 - Treatment as expenses.

Code of Federal Regulations, 2014 CFR

2014-04-01

... which he pays or incurs research or experimental expenditures. The taxpayer may do so by claiming in his... addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The request shall... shall be addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The...

26 CFR 1.174-3 - Treatment as expenses.

Code of Federal Regulations, 2012 CFR

2012-04-01

... which he pays or incurs research or experimental expenditures. The taxpayer may do so by claiming in his... addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The request shall... shall be addressed to the Commissioner of Internal Revenue, Attention: T:R, Washington, DC, 20224. The...

Workbooks to virtual worlds: a pilot study comparing educational tools to foster a culture of safety and respect in Ontario.

PubMed

Mallette, Claire; Duff, Margaret; McPhee, Carolyn; Pollex, Heather; Wood, Anya

2011-01-01

Nurses frequently experience horizontal violence in their interactions with nursing colleagues within the workplace. By definition, horizontal violence includes such disrespectful behaviours as intimidation, coercion, bullying, criticism, exclusion or belittling. Educational programs addressing horizontal violence have been developed, but few have been evaluated with respect to knowledge acquisition and transfer. The purpose of this paper is to describe an experimental effectiveness study, using a pre/post design with a control group (total N=164). The research evaluated an innovative educational program in which nurses, using avatars, role-played strategies to address horizontal violence within a virtual nursing unit developed on the Second Life platform. The results of participating in this program were compared with more traditional educational methodologies, such as a workbook and a self-directed e-learning module. While all strategies were perceived by participants as beneficial, the findings from this study suggest that learning through the self-directed e-learning module followed with practice in a virtual world is an effective way of acquiring knowledge, skills and abilities to better address horizontal violence.

Experimental and theoretical studies on the structural, spectroscopic and hydrogen bonding on 4-nitro-n-(2,4-dinitrophenyl) benzenamine

NASA Astrophysics Data System (ADS)

Subhapriya, G.; Kalyanaraman, S.; Jeyachandran, M.; Ragavendran, V.; Krishnakumar, V.

2018-04-01

Synthesized 4-nitro-N-(2,4-dinitrophenyl) benzenamine (NDPBA) molecule was confirmed applying the tool of NMR. Theoretical prediction addressed the NMR chemical shifts and correlated well with the experimental data. The molecule subjected to theoretical DFT at 6-311++G** level unraveled the spectroscopic and structural properties of the NDPBA molecule. Moreover the structural features proved the occurrence of intramolecular Nsbnd H· · O hydrogen bonding in the molecule which was further confirmed with the help of Frontier molecular orbital analysis. Vibrational spectroscopic characterization through FT-IR and Raman experimentally and theoretically gave an account for the vibrational properties. An illustration of the topology of the molecule theoretically helped also in finding the hydrogen bonding energy.

Does skill retention benefit from retentivity and symbolic rehearsal? - two studies with a simulated process control task.

PubMed

Kluge, Annette; Frank, Barbara; Maafi, Sanaz; Kuzmanovska, Aleksandra

2016-05-01

Two experiments were designed to compare two symbolic rehearsal refresher interventions (imaginary practice, a hidden introspective process) and investigate the role of retentivity in skill retention. Retentivity is investigated as the ability to memorise and reproduce information and associations that were learned a short time ago. Both experiments comprised initial training (week 1), a symbolic rehearsal for the experimental group (week 2) and a retention assessment (week 3). In the first study, the experimental group received a symbolic rehearsal, while the control group received no rehearsal. In the second study, the experimental group received the same symbolic rehearsal used in study 1, enhanced with rehearsal tasks addressing human-computer interaction. The results showed that both symbolic rehearsal interventions were equally likely to mitigate skill decay. The retentivity showed medium to high correlations with skill retention in both studies, and the results suggest that subjects high in retentivity benefit more from a symbolic rehearsal refresher intervention. Practitioner Summary: Skill decay becomes a problem in situations in which jobs require the correct mastery of non-routine situations. Two experimental studies with simulated process control tasks showed that symbolic rehearsal and retentivity can significantly mitigate skill decay and that subjects higher in retentivity benefit more from refresher interventions.

Mechanisms of Günther Tulip filter tilting during transfemoral placement.

PubMed

Matsui, Y; Horikawa, M; Ohta, K; Jahangiri Noudeh, Y; Kaufman, J A; Farsad, K

The purpose of this study was to characterize the mechanisms of Günther Tulip filter (GTF) tilting during transfemoral placement in an experimental model with further validation in a clinical series. In an experimental study, 120 GTF placements in an inferior vena cava (IVC) model were performed using 6 configurations of pre-deployment filter position. The angle between the pre-deployment filter axis and IVC axis, and the proximity of the constrained filter legs to IVC wall prior to deployment were evaluated. The association of those pre-deployment factors with post-deployment filter tilting was analyzed. The association noted in the experimental study was then evaluated in a retrospective clinical series of 21 patients. In the experimental study, there was a significant association between the pre-deployment angle and post-deployment filter tilting (P<0.0001). With a low pre-deployment angle (≤5°), a significant association was noted between filter tilting and the proximity of the constrained filter legs to the far IVC wall (P=0.001). In a retrospective clinical study, a significant association between the pre-deployment angle and post-deployment filter tilting was also noted with a linear regression model (P=0.026). Significant association of the pre-deployment angle with post-deployment GTF tilting was shown in both the experimental and clinical studies. The experimental study also showed that proximity of filter legs is relevant when pre-deployment angle is small. Addressing these factors may result in a lower incidence of filter tilting. Copyright © 2017 Editions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

Achieving external validity in home advantage research: generalizing crowd noise effects

PubMed Central

Myers, Tony D.

2014-01-01

Different factors have been postulated to explain the home advantage phenomenon in sport. One plausible explanation investigated has been the influence of a partisan home crowd on sports officials' decisions. Different types of studies have tested the crowd influence hypothesis including purposefully designed experiments. However, while experimental studies investigating crowd influences have high levels of internal validity, they suffer from a lack of external validity; decision-making in a laboratory setting bearing little resemblance to decision-making in live sports settings. This focused review initially considers threats to external validity in applied and theoretical experimental research. Discussing how such threats can be addressed using representative design by focusing on a recently published study that arguably provides the first experimental evidence of the impact of live crowd noise on officials in sport. The findings of this controlled experiment conducted in a real tournament setting offer a level of confirmation of the findings of laboratory studies in the area. Finally directions for future research and the future conduct of crowd noise studies are discussed. PMID:24917839

An Experimental Study of Medical Error Explanations: Do Apology, Empathy, Corrective Action, and Compensation Alter Intentions and Attitudes?

PubMed

Nazione, Samantha; Pace, Kristin

2015-01-01

Medical malpractice lawsuits are a growing problem in the United States, and there is much controversy regarding how to best address this problem. The medical error disclosure framework suggests that apologizing, expressing empathy, engaging in corrective action, and offering compensation after a medical error may improve the provider-patient relationship and ultimately help reduce the number of medical malpractice lawsuits patients bring to medical providers. This study provides an experimental examination of the medical error disclosure framework and its effect on amount of money requested in a lawsuit, negative intentions, attitudes, and anger toward the provider after a medical error. Results suggest empathy may play a large role in providing positive outcomes after a medical error.

Development of a measurement technique for qualitative analysis of MOS transistors using Kuhn's method for MOS varactors

NASA Astrophysics Data System (ADS)

Krautschneider, W.

The semiconductor junction region up to the oxidized surface layer is studied. The object of study is a MOS capacitor, but it is shown that the obtained values of the surface characteristics apply to more complicated MOS transistors. The metal oxide-silicon system is discussed in terms of an ideal varactor, the actual MOS structure, and the MOS system with p-n junction. The determination of the phase interface state density in MOS varactors and MOS transistors is addressed, as the quasistatic C(V) experiment of Kuhn (1970) is theoretically and experimentally extended from MOS varactors to MOS transistors. The surface recombination speed is treated, and the experimental results are compared with theoretical predictions.

Addressing Antibiotic Abuse in China: An Experimental Audit Study☆

PubMed Central

Currie, Janet; Lin, Wanchuan; Meng, Juanjuan

2016-01-01

China has high rates of antibiotic abuse and antibiotic resistance but the causes are still a matter for debate. Strong physician financial incentives to prescribe are likely to be an important cause. However, patient demand (or physician beliefs about patient demand) is often cited and may also play a role. We use an audit study to examine the effect of removing financial incentives, and to try to separate out the effects of patient demand. We implement a number of different experimental treatments designed to try to rule out other possible explanations for our findings. Together, our results suggest that financial incentives are the main driver of antibiotic abuse in China, at least in the young and healthy population we draw on in our study. PMID:26949284

Determination of some pure compound ideal-gas enthalpies of formation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steele, W. V.; Chirico, R. D.; Nguyen, A.

1989-06-01

The results of a study aimed at improvement of group-additivity methodology for estimation of thermodynamic properties of organic substances are reported. Specific weaknesses where ring corrections were unknown or next-nearest-neighbor interactions were only estimated because of lack of experimental data are addressed by experimental studies of enthalpies of combustion in the condensed- phase and vapor pressure measurements. Ideal-gas enthalpies of formation are reported for acrylamide, succinimide, ..gamma..-butyrolactone, 2-pyrrolidone, 2,3-dihydrofuran, 3,4-dihydro-2H-pyran, 1,3-cyclohexadiene, 1,4-cyclohexadiene, and 1-methyl-1-phenylhydrazine. Ring corrections, group terms, and next-nearest-neighbor interaction terms useful in the application of group additivity correlations are derived. 44 refs., 2 figs., 59 tabs.

Predictive Validity of an Empirical Approach for Selecting Promising Message Topics: A Randomized-Controlled Study

PubMed Central

Lee, Stella Juhyun; Brennan, Emily; Gibson, Laura Anne; Tan, Andy S. L.; Kybert-Momjian, Ani; Liu, Jiaying; Hornik, Robert

2016-01-01

Several message topic selection approaches propose that messages based on beliefs pretested and found to be more strongly associated with intentions will be more effective in changing population intentions and behaviors when used in a campaign. This study aimed to validate the underlying causal assumption of these approaches which rely on cross-sectional belief–intention associations. We experimentally tested whether messages addressing promising themes as identified by the above criterion were more persuasive than messages addressing less promising themes. Contrary to expectations, all messages increased intentions. Interestingly, mediation analyses showed that while messages deemed promising affected intentions through changes in targeted promising beliefs, messages deemed less promising also achieved persuasion by influencing nontargeted promising beliefs. Implications for message topic selection are discussed. PMID:27867218

The First Moment of Azimuthal Anisotropy in Nuclear Collisions from AGS to LHC Energies

DOE PAGES

Singha, Subhash; Shanmuganathan, Prashanth; Keane, Declan

2016-10-01

We reviewmore » topics related to the first moment of azimuthal anisotropy ( v 1 ), commonly known as directed flow, focusing on both charged particles and identified particles from heavy-ion collisions. Beam energies from the highest available, at the CERN LHC, down to projectile kinetic energies per nucleon of a few GeV per nucleon, as studied in experiments at the Brookhaven AGS, fall within our scope. We focus on experimental measurements and on theoretical work where direct comparisons with experiment have been emphasized. The physics addressed or potentially addressed by this review topic includes the study of Quark Gluon Plasma and, more generally, investigation of the Quantum Chromodynamics phase diagram and the equation of state describing the accessible phases.« less

Jefferson Lab Science: Present and Future

DOE PAGES

McKeown, Robert D.

2015-02-12

The Continuous Electron Beam Accelerator Facility (CEBAF) and associated experimental equipment at Jefferson Lab comprise a unique facility for experimental nuclear physics. Furthermore, this facility is presently being upgraded, which will enable a new experimental program with substantial discovery potential to address important topics in nuclear, hadronic, and electroweak physics. Further in the future, it is envisioned that the Laboratory will evolve into an electron-ion colliding beam facility.

Experimental Flight Characterization of a Canard-Controlled, Subsonic Missile

DTIC Science & Technology

2017-08-01

ARL-TR-8086 ● AUG 2017 US Army Research Laboratory Experimental Flight Characterization of a Canard- Controlled , Subsonic Missile...Laboratory Experimental Flight Characterization of a Canard- Controlled , Subsonic Missile by Frank Fresconi, Ilmars Celmins, James Maley, and...valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) August 2017 2. REPORT TYPE Technical

From experimental systems to evolutionary biology: an impossible journey?

PubMed

Morange, Michel

2013-01-01

The historical approach to the sciences has undergone a sea change during recent decades. Maybe the major contribution of Hans-Jörg Rheinberger to this movement was his demonstration of the importance of experimental systems, and of their transformations, in the development of the sciences. To describe these transformations, Hans-Jörg borrows metaphors from evolutionary biology. I want to argue that evolutionary biologists can find in these recent historical studies plenty of models and concepts to address unresolved issues in their discipline. At a time when transdisciplinarity is highly praised, it is useful to provide a precise description of the obstacles that have so far prevented this exchange.

Expression-invariant representations of faces.

PubMed

Bronstein, Alexander M; Bronstein, Michael M; Kimmel, Ron

2007-01-01

Addressed here is the problem of constructing and analyzing expression-invariant representations of human faces. We demonstrate and justify experimentally a simple geometric model that allows to describe facial expressions as isometric deformations of the facial surface. The main step in the construction of expression-invariant representation of a face involves embedding of the facial intrinsic geometric structure into some low-dimensional space. We study the influence of the embedding space geometry and dimensionality choice on the representation accuracy and argue that compared to its Euclidean counterpart, spherical embedding leads to notably smaller metric distortions. We experimentally support our claim showing that a smaller embedding error leads to better recognition.

The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII)

NASA Technical Reports Server (NTRS)

Rinehart, Stephen A.

2010-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding of the universe. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scale on which mid-to far-infrared emission arises. We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII), an eight-meter Michelson interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks in young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers.

BETTII: The Balloon Experimental Twin Telescope for Infrared Interferometry

NASA Technical Reports Server (NTRS)

Rinehart, Stephen

2011-01-01

Astronomical studies at infrared wavelengths have dramatically improved our understanding the universe. The relatively low angular resolution of these missions, however, is insufficient to resolve the physical scale on which mid-to far-infrared emission arises. We will build the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII),8oeight-meter Michelson interferometer to fly on a high-altitude balloon. BETTII's spectral-spatial capability, provided by an instrument using double-Fourier techniques, will address key questions about the nature of disks io young star clusters and active galactic nuclei and the envelopes of evolved stars. BETTII will also lay the technological groundwork for future space interferometers.

Characterization and application of a laser-driven intense pulsed neutron source using Trident

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vogel, Sven C.

A team of Los Alamos researchers supported a final campaign to use the Trident laser to produce neutrons, contributed their multidisciplinary expertise to experimentally assess if laser-driven neutron sources can be useful for MaRIE. MaRIE is the Laboratory’s proposed experimental facility for the study of matter-radiation interactions in extremes. Neutrons provide a radiographic probe that is complementary to x-rays and protons, and can address imaging challenges not amenable to those beams. The team's efforts characterize the Laboratory’s responsiveness, flexibility, and ability to apply diverse expertise where needed to perform successful complex experiments.

Frequent Questions about Starting-up New Composite Wood Mills and the Use of Experimental Products and Resins

EPA Pesticide Factsheets

The following frequently asked questions (FAQs) address issues relating to starting-up new doestice composite wood mills and the use of experimental product and resin systems under the Formaldehyde Emission Standards for Composite Wood Products final rule

Frequently Asked Questions on Starting-up New Composite Wood Mills and the Use of Experimental Products and Resins

EPA Pesticide Factsheets

The following frequently asked questions (FAQs) address issues relating to starting-up new doestice composite wood mills and the use of experimental product and resin systems under the Formaldehyde Emission Standards for Composite Wood Products final rule

Theoretical and Experimental Estimations of Volumetric Inductive Phase Shift in Breast Cancer Tissue

NASA Astrophysics Data System (ADS)

González, C. A.; Lozano, L. M.; Uscanga, M. C.; Silva, J. G.; Polo, S. M.

2013-04-01

Impedance measurements based on magnetic induction for breast cancer detection has been proposed in some studies. This study evaluates theoretical and experimentally the use of a non-invasive technique based on magnetic induction for detection of patho-physiological conditions in breast cancer tissue associated to its volumetric electrical conductivity changes through inductive phase shift measurements. An induction coils-breast 3D pixel model was designed and tested. The model involves two circular coils coaxially centered and a human breast volume centrally placed with respect to the coils. A time-harmonic numerical simulation study addressed the effects of frequency-dependent electrical properties of tumoral tissue on the volumetric inductive phase shift of the breast model measured with the circular coils as inductor and sensor elements. Experimentally; five female volunteer patients with infiltrating ductal carcinoma previously diagnosed by the radiology and oncology departments of the Specialty Clinic for Women of the Mexican Army were measured by an experimental inductive spectrometer and the use of an ergonomic inductor-sensor coil designed to estimate the volumetric inductive phase shift in human breast tissue. Theoretical and experimental inductive phase shift estimations were developed at four frequencies: 0.01, 0.1, 1 and 10 MHz. The theoretical estimations were qualitatively in agreement with the experimental findings. Important increments in volumetric inductive phase shift measurements were evident at 0.01MHz in theoretical and experimental observations. The results suggest that the tested technique has the potential to detect pathological conditions in breast tissue associated to cancer by non-invasive monitoring. Further complementary studies are warranted to confirm the observations.

Experimental and theoretical modelling of sand-water-object interaction under nonlinear progressive waves

NASA Astrophysics Data System (ADS)

Testik, Firat Yener

An experimental and theoretical study has been conducted to obtain a fundamental understanding of the dynamics of the sand, water and a solid object interaction as progressive gravity waves impinge on a sloping beach. Aside from obvious scientific interest, this exceedingly complex physical problem is important for naval applications, related to the behavior of disk/cylindrical shaped objects (mines) in the coastal waters. To address this problem, it was divided into a set of simpler basic problems. To begin, nonlinear progressive waves were investigated experimentally in a wave tank for the case of a rigid (impermeable) sloping bottom. Parameterizations for wave characteristics were proposed and compared with the experiments. In parallel, a numerical wave tank model (NWT) was calibrated using experimental data from a single run, and wave field in the wave tank was simulated numerically for the selected experiments. Subsequently, a layer of sand was placed on the slope and bottom topography evolution processes (ripple and sandbar dynamics, bottom topography relaxation under variable wave forcing, etc.) were investigated experimentally. Models for those processes were developed and verified by experimental measurements. Flow over a circular cylinder placed horizontally on a plane wall was also studied. The far-flow field of the cylinder placed in the wave tank was investigated experimentally and numerical results from the NWT simulations were compared with the experimental data. In the mean time, the near-flow velocity/vorticity field around a short cylinder under steady and oscillatory flow was studied in a towing tank. Horseshoe vortex formation and periodic shedding were documented and explained. With the understanding gained through the aforementioned studies, dynamics and burial/scour around the bottom objects in the wave tank were studied. Possible scenarios on the behavior of the disk-shaped objects were identified and explained. Scour around 3D cylindrical objects was investigated. Different scour regimes were identified experimentally and explained theoretically. Proper physical parameterizations on the time evolution and equilibrium scour characteristics were proposed and verified experimentally.

Problems associated with the utilization of algae in bioregenerative life support systems

NASA Technical Reports Server (NTRS)

Averner, M. M.; Karel, M.; Radmer, R.

1984-01-01

A workshop was conducted to identify the potential problems associated with the use of microalgae in biorregenerative life support systems, and to identify algae rlated research issues that must be addressed through space flight experimentation. Major questions to be resolved relate to the choice of algal species for inclusion in a bioregenerative life support system, their long term behavior in the space environment, and the nature of the techniques required for the continuous growth of algae on the scale required. Consideration was given to the problems associated with the conversion of algal biomass into edible components. Specific concerns were addressed and alternative transformation processes identified and compared. The workshop identified the following major areas to be addressed by space flight experimentation: (1) long term culture stability, (2) optimal design of algal growth reactors, and (3) post growth harvesting and processing in the space environment.

Mathematical and computational approaches can complement experimental studies of host-pathogen interactions.

PubMed

Kirschner, Denise E; Linderman, Jennifer J

2009-04-01

In addition to traditional and novel experimental approaches to study host-pathogen interactions, mathematical and computer modelling have recently been applied to address open questions in this area. These modelling tools not only offer an additional avenue for exploring disease dynamics at multiple biological scales, but also complement and extend knowledge gained via experimental tools. In this review, we outline four examples where modelling has complemented current experimental techniques in a way that can or has already pushed our knowledge of host-pathogen dynamics forward. Two of the modelling approaches presented go hand in hand with articles in this issue exploring fluorescence resonance energy transfer and two-photon intravital microscopy. Two others explore virtual or 'in silico' deletion and depletion as well as a new method to understand and guide studies in genetic epidemiology. In each of these examples, the complementary nature of modelling and experiment is discussed. We further note that multi-scale modelling may allow us to integrate information across length (molecular, cellular, tissue, organism, population) and time (e.g. seconds to lifetimes). In sum, when combined, these compatible approaches offer new opportunities for understanding host-pathogen interactions.

The Classroom Performance System (CPS): Effects on student participation, attendance, and achievement in multicultural anatomy and physiology classes at South Texas College

NASA Astrophysics Data System (ADS)

Termos, Mohamad Hani

2011-12-01

The Classroom Performance System (CPS) is an instructional technology tool that increases student performance and addresses different learning styles. Instructional technologies are used to promote active learning; however, student embarrassment issue in a multicultural setting is not addressed. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes at South Texas College, where the first spoken language is not English. Quantitative method and quasi-experimental design were employed and comparative statistic methods and pre-post tests were used to collect the data. Participants were college students and sections of study were selected by convenient sampling. Participation was 100% during most of the lectures held and participation rate did not strike above 68% in control group. Attendance was significantly higher in CPS sections than the control group as shown by t-tests. Experimental sections had a higher increase in the pre-post test scores and student averages on lecture exams increased at a higher rate as compared to the control group. Therefore, the CPS increased student participation, attendance, and achievement in multicultural anatomy and physiology classes. The CPS can be studied in other settings where the first spoken language is English or in other programs, such as special education programs. Additionally, other variables can be studied and other methodologies can be employed.

Acute ethanol administration affects zebrafish preference for a biologically inspired robot.

PubMed

Spinello, Chiara; Macrì, Simone; Porfiri, Maurizio

2013-08-01

Preclinical animal models constitute a cornerstone against which the reward processes involved in drug addiction are often studied and dissected. While rodents have traditionally represented the species of choice, a growing body of literature indicates that zebrafish are emerging as a valuable model organism. Specifically, several studies demonstrate that the effects of ethanol at the level of emotional- and cognitive-related domains can be reliably investigated using zebrafish. The rapidly evolving nature of these efforts allows substantial room for the development of novel experimental paradigms suited to this freshwater species. The field of ethorobotics may prove particularly beneficial, due to its ability to convey fully controllable and easily reproducible experimental tools. In this study, we addressed the possibility of using a biologically inspired robot to investigate the emotionally related properties of ethanol in a preference task in zebrafish. To this aim, we evaluated wild-type zebrafish preference toward a robotic stimulus and addressed whether ethanol administration (0.25% and 1.00% ethanol/water concentration) may alter such preferences. In accordance with our previous studies, we observed that zebrafish exhibit a natural attraction toward the robot. Additionally, in agreement with our predictions, we showed that ethanol administration abolishes such preferences. This work is the first to demonstrate that robotic stimuli can be used in zebrafish to investigate the reward-related properties of alcohol. Copyright © 2013 Elsevier Inc. All rights reserved.

Experimental entanglement of 25 individually accessible atomic quantum interfaces.

PubMed

Pu, Yunfei; Wu, Yukai; Jiang, Nan; Chang, Wei; Li, Chang; Zhang, Sheng; Duan, Luming

2018-04-01

A quantum interface links the stationary qubits in a quantum memory with flying photonic qubits in optical transmission channels and constitutes a critical element for the future quantum internet. Entanglement of quantum interfaces is an important step for the realization of quantum networks. Through heralded detection of photon interference, we generate multipartite entanglement between 25 (or 9) individually addressable quantum interfaces in a multiplexed atomic quantum memory array and confirm genuine 22-partite (or 9-partite) entanglement. This experimental entanglement of a record-high number of individually addressable quantum interfaces makes an important step toward the realization of quantum networks, long-distance quantum communication, and multipartite quantum information processing.

Experimental hypervigilance changes the intensity/unpleasantness ratio of pressure sensations: evidence for the generalized hypervigilance hypothesis.

PubMed

Hollins, Mark; Walters, Sloan

2016-06-01

Patients with chronic pain conditions such as fibromyalgia often demonstrate hypervigilance-undue alertness for unpleasant or threatening bodily sensations-as well as enhancement of these sensations. The generalized hypervigilance hypothesis (GHH) of Rollman and colleagues asserts that hypervigilance leads to this perceptual amplification. However, cause-and-effect relationships are difficult to establish in studies using a quasi-experimental design. In the present study, we sought to address this issue by attempting to induce hypervigilance experimentally, in one of two groups to which young, healthy adults had been randomly assigned. Those in the experimental group wrote about the flu and practiced counting their own blinks, breaths, and heartbeats; those in the control group wrote about a neutral topic and counted innocuous lights and sounds. Next, both groups rated the intensity and unpleasantness of pressure sensations (ranging from mild to painful) caused by a series of applications of a weighted rod to the forearm. The intensity/unpleasantness ratio of these ratings was significantly greater in the experimental group, suggesting that induced hypervigilance had caused perceptual amplification that generalized to pressure sensations, which had not been part of the experimental manipulation. Psychometric measures of anxiety and catastrophizing were equivalent in the two groups, indicating that the experimental manipulation operated via attentional rather than emotional changes. The results support the GHH.

The Impact of School of Attendance, Classroom, Interventionist, Ethnicity, and Level of Educational Support on Oral Reading Fluency Measures

ERIC Educational Resources Information Center

Preston, Andrew James

2013-01-01

Response to intervention (RtI) is an approach to assist students with learning difficulties. There is limited research into the effectiveness of RtI within rural school districts. To address that gap, this quantitative, experimental study tested the theory of RtI, comparing the tier of intervention to oral reading fluency, controlling for…

Decisionmaking in Military Command Teams: An Experimental Study

DTIC Science & Technology

1992-03-01

of the problems that remain to be solved by systems designers . The Fogarty report concluded that "The AEGIS combat system’s performance was excellent...1989). He maintains that the designers of the AEGIS system failed to incorporate enough human engineering in their design . Without addressing the fault...Naval Command Teams (RAINCOAT), Composite Warfare Commander - Destributed Dynamc Decisionmaking ICWC-[I)), resource coordination, resource effectiveness

Using existing thinning studies to investigate the carbon consequences of thinning: learning from the past to craft the future

Treesearch

Coeli M. Hoover

2010-01-01

Although long-term research is a critical tool for answering forest management questions, managers must often make decisions before results from such experiments are available. One way to meet those information needs is to reanalyze existing long-term data sets to address current research questions; the Forest Service Experimental Forests and Ranges (EFRs) network...

Mid-infrared plasmonic resonances exploiting heavily-doped Ge on Si

NASA Astrophysics Data System (ADS)

Biagioni, P.; Sakat, E.; Baldassarre, L.; Calandrini, E.; Samarelli, A.; Gallacher, K.; Frigerio, J.; Isella, G.; Paul, D. J.; Ortolani, M.

2015-03-01

We address the behavior of mid-infrared localized plasmon resonances in elongated germanium antennas integrated on silicon substrates. Calculations based on Mie theory and on the experimentally retrieved dielectric constant allow us to study the tunability and the figures of merit of plasmon resonances in heavily-doped germanium and to preliminarily compare them with those of the most established plasmonic material, gold.

Exploring Variation in the Impact of Dual-Credit Coursework on Postsecondary Outcomes: A Quasi-Experimental Analysis of Texas Students

ERIC Educational Resources Information Center

Giani, Matthew; Alexander, Celeste; Reyes, Pedro

2014-01-01

Despite the growing popularity of dual-credit courses as a college readiness strategy, numerous reviews of the literature have noted a number of important limitations of the research on the effects of dual-credit on student postsecondary outcomes. This study addressed these gaps in the literature by estimating the impact of dual-credit courses on…

Metering Self-Reported Adherence to Clinical Outcomes in Malaysian Patients with Hypertension: Applying the Stages of Change Model to Healthful Behaviors in the CORFIS Study

ERIC Educational Resources Information Center

Karupaiah, Tilakavati; Wong, Kimberly; Chinna, Karuthan; Arasu, Kanimolli; Chee, Winnie Siew Swee

2015-01-01

The CORFIS ("Community-Based Cardiovascular Risk Factors Intervention Strategies") program was piloted in community clinics in Malaysia to address the lack of health education in chronic disease management. The stages of change model was applied in a multicenter quasi-experimental design to evaluate adherence to advocated behaviors in…

Polarization observables in few nucleon systems with CLAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zachariou, Nicholas

The CEBAF Large Acceptance Spectrometer (CLAS), housed in Hall-B at the Thomas Jefferson National Accelerator Facility provides us with the experimental tools to study strongly-interacting matter and its dynamics in the transition from hadronic to partonic degrees of freedom in nuclear interactions. In this paper we discuss the progress made in understanding the relevant degrees of freedom using polarisation observables of deuteron photodisintegration in the few-GeV photon-energy region. We also address progress made in studying the interaction between Hyperons and Nucleons via polarisation observables, utilising high-statistics experiments that provided us with the large data samples needed to study final-state interactions,more » as well as perform detailed studies on initial-state effects. The polarisation observables presented here provide us with unique experimental tools to study the underlying dynamics of both initial and final-state interactions, as well as the information needed to disentangle signal from background contributions.« less

Polarization observables in few nucleon systems with CLAS

DOE PAGES

Zachariou, Nicholas

2017-12-01

The CEBAF Large Acceptance Spectrometer (CLAS), housed in Hall-B at the Thomas Jefferson National Accelerator Facility provides us with the experimental tools to study strongly-interacting matter and its dynamics in the transition from hadronic to partonic degrees of freedom in nuclear interactions. In this paper we discuss the progress made in understanding the relevant degrees of freedom using polarisation observables of deuteron photodisintegration in the few-GeV photon-energy region. We also address progress made in studying the interaction between Hyperons and Nucleons via polarisation observables, utilising high-statistics experiments that provided us with the large data samples needed to study final-state interactions,more » as well as perform detailed studies on initial-state effects. The polarisation observables presented here provide us with unique experimental tools to study the underlying dynamics of both initial and final-state interactions, as well as the information needed to disentangle signal from background contributions.« less

Animal-Assisted Therapies for Youth with or at risk for Mental Health Problems: A Systematic Review.

PubMed

Hoagwood, Kimberly Eaton; Acri, Mary; Morrissey, Meghan; Peth-Pierce, Robin

2017-01-01

To systematically review experimental evidence about animal-assisted therapies (AAT) for children or adolescents with or at risk for mental health conditions, we reviewed all experimental AAT studies published between 2000-2015, and compared studies by animal type, intervention, and outcomes. Studies were included if used therapeutically for children and adolescents (≤21 years) with or at risk for a mental health problem; used random assignment or a waitlist comparison/control group; and included child-specific outcome data. Of 1,535 studies, 24 met inclusion criteria. Of 24 studies identified, almost half were randomized controlled trials, with 9 of 11 published in the past two years. The largest group addresses equine therapies for autism. Findings are generally promising for positive effects associated with equine therapies for autism and canine therapies for childhood trauma. The AAT research base is slim; a more focused research agenda is outlined.

A Systematic Review of Interventions on Patients' Social and Economic Needs.

PubMed

Gottlieb, Laura M; Wing, Holly; Adler, Nancy E

2017-11-01

Healthcare systems are experimenting increasingly with interventions to address patients' social and economic needs. This systematic review examines how often and how rigorously interventions bridging social and medical care have been evaluated. The review included literature from PubMed published between January 2000 and February 2017. Additional studies were identified by reference searches and consulting local experts. Included studies were based in the U.S.; addressed at least one social or economic determinant of health (e.g., housing, employment, food insecurity); and were integrated within the medical care delivery system. Data from included studies were abstracted in June 2015 (studies published January 2000-December 2014) and in March 2017 (studies published January 2015-February 2017). Screening of 4,995 articles identified 67 studies of 37 programs addressing social needs. Interventions targeted a broad range of social needs and populations. Forty studies involved non-experimental designs. There was wide heterogeneity in outcome measures selected. More studies reported findings associated with process (69%) or social or economic determinants of health (48%) outcomes than health (30%) or healthcare utilization or cost (27%) outcomes. Studies reporting health, utilization, or cost outcomes reported mixed results. Healthcare systems increasingly incorporate programs to address patients' social and economic needs in the context of care. But evaluations of these programs to date focus primarily on process and social outcomes and are often limited by poor study quality. Higher-quality studies that include common health and healthcare utilization outcomes would advance effectiveness research in this rapidly expanding field. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

Nanostructured diamine-fullerene derivatives: computational density functional theory study and experimental evidence for their formation via gas-phase functionalization.

PubMed

Contreras-Torres, Flavio F; Basiuk, Elena V; Basiuk, Vladimir A; Meza-Laguna, Víctor; Gromovoy, Taras Yu

2012-02-16

Nanostructure derivatives of fullerene C(60) are used in emerging applications of composite matrices, including protective and decorative coating, superadsorbent material, thin films, and lightweight high-strength fiber-reinforced materials, etc. In this study, quantum chemical calculations and experimental studies were performed to analyze the derivatives of diamine-fullerene prepared by the gas-phase solvent-free functionalization technique. In particular, the aliphatic 1,8-diamino-octane and the aromatic 1,5-diaminonaphthalene, which are diamines volatile in vacuum, were studied. We addressed two alternative mechanisms of the amination reaction via polyaddition and cross-linking of C(60) with diamines, using the pure GGA BLYP, PW91, and PBE functionals; further validation calculations were performed using the semiempirical dispersion GGA B97-D functional which contains parameters that have been specially adjusted by a more realistic view on dispersion contributions. In addition, we looked for experimental evidence for the covalent functionalization by using laser desorption/ionization time-of-flight mass spectrometry, thermogravimetric analysis, and atomic force microscopy.

77 FR 64566 - Market Test of Experimental Product-Metro Post

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-22

... Metro Post. This document describes the proposed test, addresses procedural aspects of the filing, and.... \\1\\ Notice of the United States Postal Service of Market Test of Experimental Product--Metro Post... the Metro Post market test under seal. Notice at 4. The Postal Service classifies Metro Post as a...

Frequently Asked Questions on Starting-up New Domestic Composite Wood Mills and the Use of Experimental Products and Resins

EPA Pesticide Factsheets

The following frequently asked questions (FAQs) address issues relating to starting-up new doestice composite wood mills and the use of experimental product and resin systems under the Formaldehyde Emission Standards for Composite Wood Products final rule

Accuracy of Nonverbal Communication as Determinant of Interpersonal Expectancy Effects

ERIC Educational Resources Information Center

Zuckerman, Miron; And Others

1978-01-01

The person perception paradigm was used to address the effects of experimenters' ability to encode nonverbal cues and subjects' ability to decode nonverbal cues on magnitude of expectancy effects. Greater expectancy effects were obtained when experimenters were better encoders and subjects were better decoders of nonverbal cues. (Author)

Establishing a "Centre for Engineering Experimentation and Design Simulation": A Step towards Restructuring Engineering Education in India

ERIC Educational Resources Information Center

Venkateswarlu, P.

2017-01-01

Reforms in undergraduate engineering curriculum to produce engineers with entrepreneurial skills should address real-world problems relevant to industry and society with active industry support. Technology-assisted, hands-on projects involving experimentation, design simulation and prototyping will transform graduates into professionals with…

Selective Optical Addressing of Nuclear Spins through Superhyperfine Interaction in Rare-Earth Doped Solids.

PubMed

Car, B; Veissier, L; Louchet-Chauvet, A; Le Gouët, J-L; Chanelière, T

2018-05-11

In Er^{3+}:Y_{2}SiO_{5}, we demonstrate the selective optical addressing of the ^{89}Y^{3+} nuclear spins through their superhyperfine coupling with the Er^{3+} electronic spins possessing large Landé g factors. We experimentally probe the electron-nuclear spin mixing with photon echo techniques and validate our model. The site-selective optical addressing of the Y^{3+} nuclear spins is designed by adjusting the magnetic field strength and orientation. This constitutes an important step towards the realization of long-lived solid-state qubits optically addressed by telecom photons.

Selective Optical Addressing of Nuclear Spins through Superhyperfine Interaction in Rare-Earth Doped Solids

NASA Astrophysics Data System (ADS)

Car, B.; Veissier, L.; Louchet-Chauvet, A.; Le Gouët, J.-L.; Chanelière, T.

2018-05-01

In Er3 +:Y2SiO5 , we demonstrate the selective optical addressing of the Y89 3 + nuclear spins through their superhyperfine coupling with the Er3 + electronic spins possessing large Landé g factors. We experimentally probe the electron-nuclear spin mixing with photon echo techniques and validate our model. The site-selective optical addressing of the Y3 + nuclear spins is designed by adjusting the magnetic field strength and orientation. This constitutes an important step towards the realization of long-lived solid-state qubits optically addressed by telecom photons.

The HPS experiment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Colaneri, Luca

2017-04-01

With the experimental discovery of the Higgs boson, the Standard Model has been considered veri ed in all its previsions. The Standard Model, though, is still considered an incomplete theory, because it fails to address many theoretical and phenomenological issues. Among those, it doesn't provide any viable Dark Matter candidate. Many Beyond-Standard Model theories, such as the Supersymmetric Standard Model, provide possible solutions. In this work we have reported the experimental observations that led to considerate the existence of a new Force, mediated by a new massive vector boson, that could address all the observed phenomenology. This new dark Forcemore » could open an observational channel between the Standard Model and a new Dark Sector, convey by the interaction of the Standard Model photon with the massive dark photon, also called the A'. Purpose of this work was to develop an independent study of the background processes and the implementation of an independent event generator, to better understand the kinematics of the produced particles in the process e - +W → e - +W' + e + + e - and validate, or invalidate, the o cial event generator.« less

Vibrational pumping and heating under SERS conditions: fact or myth?

PubMed

Le Ru, E C; Etchegoin, P G

2006-01-01

We address in this paper the long debated issue of the possibility of vibrational pumping under Surface Enhanced Raman Scattering (SERS) conditions, both theoretically and experimentally. We revisit with simple theoretical models the mechanisms of vibrational pumping and its relation to heating. This presentation provides a clear classification of the various regimes of heating/pumping, from simple global laser heating to selective pumping of a single vibrational mode. We also propose the possibility of extreme pumping driven by stimulated phonon emission, and we introduce and apply a new experimental technique to study these effects in SERS. Our method relies on correlations between Raman peak parameters, and cross-correlation for two Raman peaks. We find strong evidence for local and dynamical heating, but no convincing evidence for selective pumping under our specific experimental SERS conditions.

Data mining the EXFOR database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, David A.; Hirdt, John; Herman, Michal

2013-12-13

The EXFOR database contains the largest collection of experimental nuclear reaction data available as well as this data's bibliographic information and experimental details. We created an undirected graph from the EXFOR datasets with graph nodes representing single observables and graph links representing the connections of various types between these observables. This graph is an abstract representation of the connections in EXFOR, similar to graphs of social networks, authorship networks, etc. Analysing this abstract graph, we are able to address very specific questions such as 1) what observables are being used as reference measurements by the experimental community? 2) are thesemore » observables given the attention needed by various standards organisations? 3) are there classes of observables that are not connected to these reference measurements? In addressing these questions, we propose several (mostly cross section) observables that should be evaluated and made into reaction reference standards.« less

Influence of ambient pressure on surface structures generated by ultrashort laser pulse irradiation

NASA Astrophysics Data System (ADS)

JJ Nivas, J.; Allahyari, E.; Gesuele, F.; Maddalena, P.; Fittipaldi, R.; Vecchione, A.; Bruzzese, R.; Amoruso, S.

2018-02-01

We report an experimental investigation on the surface structures induced by linearly polarized ≈ 900 fs laser pulses, at λ = 1055 nm, on silicon at different values of the ambient pressure, from 10-4 mbar to one atmosphere. Our experimental findings address interesting influences of the surrounding pressure on: (1) the spatial period of ripples; (2) the formation of micro-grooves; (3) the shape of the structured area. Moreover, the effects of various states of polarization in vacuum as well as of circularly polarized pulses in air vs vacuum are also addressed. We identify as one possible key element of such experimental observations: the fact that as the pressure raises the ablated nanoparticles produced during the femtosecond ablation process of the target get deposited more and more on the sample surface covering the irradiated spot area and influencing the structuring process.

Multiaxial Creep-Fatigue and Creep-Ratcheting Failures of Grade 91 and Haynes 230 Alloys Toward Addressing Design Issues of Gen IV Nuclear Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hassan, Tasnim; Lissenden, Cliff; Carroll, Laura

The proposed research will develop systematic sets of uniaxial and multiaxial experimental data at a very high temperature (850-950°C) for Alloy 617. The loading histories to be prescribed in the experiments will induce creep-fatigue and creep-ratcheting failure mechanisms. These experimental responses will be scrutinized in order to quantify the influences of temperature and creep on fatigue and ratcheting failures. A unified constitutive model (UCM) will be developed and validated against these experimental responses. The improved UCM will be incorporated into the widely used finite element commercial software packages ANSYS. The modified ANSYS will be validated so that it can bemore » used for evaluating the very high temperature ASME-NH design-by-analysis methodology for Alloy 617 and thereby addressing the ASME-NH design code issues.« less

Basic and applied studies of the ram accelerator as a hypervelocity projectile launcher

NASA Astrophysics Data System (ADS)

Bruckner, Adam P.; Knowlen, Carl

1993-12-01

The potential of using ram accelerator technology for an impulsive launcher of autonomously guided interceptors, such as the LEAP, has been studied during this contract period. In addition, fundamental investigations on some of the engineering issues which must be addressed for enabling ram accelerator propulsive modes to operate at 4 km/sec have been undertaken. An experimental investigation of the gas dynamic limits of ram accelerator operation has demonstrated the existence of two distinct limiting mechanisms that must be accounted for when designing projectiles for these launchers. Other experiments were conducted to make detailed pressure measurements of the flow fields at the tube walls to study the effects of projectile canting. Results from this LEAP launcher study and the experimental investigations indicate that the ram accelerator technology is well suited for applications as a transportable launcher capable of meeting the needs of theater ballistic missile defense missions.

Designing Studies That Would Address the Multilayered Nature of Health Care

PubMed Central

Pennell, Michael; Rhoda, Dale; Hade, Erinn M.; Paskett, Electra D.

2010-01-01

We review design and analytic methods available for multilevel interventions in cancer research with particular attention to study design, sample size requirements, and potential to provide statistical evidence for causal inference. The most appropriate methods will depend on the stage of development of the research and whether randomization is possible. Early on, fractional factorial designs may be used to screen intervention components, particularly when randomization of individuals is possible. Quasi-experimental designs, including time-series and multiple baseline designs, can be useful once the intervention is designed because they require few sites and can provide the preliminary evidence to plan efficacy studies. In efficacy and effectiveness studies, group-randomized trials are preferred when randomization is possible and regression discontinuity designs are preferred otherwise if assignment based on a quantitative score is possible. Quasi-experimental designs may be used, especially when combined with recent developments in analytic methods to reduce bias in effect estimates. PMID:20386057

"I feel fat": an experimental induction of body displacement in disordered eating.

PubMed

McFarlane, Traci; Urbszat, Dax; Olmsted, Marion P

2011-04-01

Body displacement, the theory that predicts that individuals with eating disorders will displace negative feelings about themselves onto their body, was tested experimentally in this study. Unrestrained eaters (n = 61), restrained eaters (n = 33), and individuals with eating disorders (n = 26) were randomly assigned to a control condition or an ineffectiveness induction. In the ineffectiveness condition participants were asked to recall and reflect on a past experience when they felt useless or incapable (i.e., ineffective). Results showed that individuals with eating disorders who were made to feel ineffective reported more implicit appearance/body concern than those in the control condition. Unrestrained and restrained eaters did not show this effect. This is the first experimental study to support body displacement theory. These data can be used clinically to educate and encourage patients with eating disorders to address thoughts and feelings related to ineffectiveness directly, instead of displacing this distress onto their body and potentially perpetuating their eating disorder. Copyright © 2011 Elsevier Ltd. All rights reserved.

Interaction between IGFBP7 and insulin: a theoretical and experimental study

NASA Astrophysics Data System (ADS)

Ruan, Wenjing; Kang, Zhengzhong; Li, Youzhao; Sun, Tianyang; Wang, Lipei; Liang, Lijun; Lai, Maode; Wu, Tao

2016-04-01

Insulin-like growth factor binding protein 7 (IGFBP7) can bind to insulin with high affinity which inhibits the early steps of insulin action. Lack of recognition mechanism impairs our understanding of insulin regulation before it binds to insulin receptor. Here we combine computational simulations with experimental methods to investigate the interaction between IGFBP7 and insulin. Molecular dynamics simulations indicated that His200 and Arg198 in IGFBP7 were key residues. Verified by experimental data, the interaction remained strong in single mutation systems R198E and H200F but became weak in double mutation system R198E-H200F relative to that in wild-type IGFBP7. The results and methods in present study could be adopted in future research of discovery of drugs by disrupting protein-protein interactions in insulin signaling. Nevertheless, the accuracy, reproducibility, and costs of free-energy calculation are still problems that need to be addressed before computational methods can become standard binding prediction tools in discovery pipelines.

Advancing Scientific Reasoning in Upper Elementary Classrooms: Direct Instruction Versus Task Structuring

NASA Astrophysics Data System (ADS)

Lazonder, Ard W.; Wiskerke-Drost, Sjanou

2015-02-01

Several studies found that direct instruction and task structuring can effectively promote children's ability to design unconfounded experiments. The present study examined whether the impact of these interventions extends to other scientific reasoning skills by comparing the inquiry activities of 55 fifth-graders randomly assigned to one of three conditions. Children in the control condition investigated a four-variable inquiry task without additional support. Performance of this task in the direct instruction condition was preceded by a short training in experimental design, whereas children in the task structuring condition, who did not receive the introductory training, were given a version of the task that addressed the four variables one at a time. Analysis of children's experimentation behavior confirmed that direct instruction and task structuring are equally effective and superior to unguided inquiry. Both interventions also evoked more determinate predictions and valid inferences. These findings demonstrate that the effect of short-term interventions designed to promote unconfounded experimentation extends beyond the control of variables.

An Overview of the RTO Symposium on Vortex Flow and High Angle of Attack Aerodynamics

NASA Technical Reports Server (NTRS)

Luckring, James M.

2002-01-01

In May of 2001 the Research and Technology Organization (RTO) sponsored a symposium on Vortex Flow and High Angle of Attack aerodynamics. Forty-six papers, organized into nine sessions, addressed computational and experimental studies of vortex flows pertinent to both aircraft and maritime applications. The studies also ranged from fundamental fluids investigations to flight test results. Selected highlights are included in this paper to provide a perspective toward the scope of the full symposium.

Overview of ECRH experimental results

NASA Astrophysics Data System (ADS)

Lloyd, Brian

1998-08-01

A review of the present status of electron cyclotron heating and current drive experiments in toroidal fusion devices is presented. In addition to basic heating and current drive studies the review also addresses advances in wave physics and the application of electron cyclotron waves for instability control, transport studies, pre-ionization/start-up assist, etc. A comprehensive overview is given with particular emphasis on recent advances since the major review of Erckmann and Gasparino (1994) ( 36 1869), including results from the latest generation of high-power, high-frequency experiments.

Smoking: what has been addressed in Brazilian journals.

PubMed

Prado, Gustavo Faibischew; Lombardi, Elisa Maria Siqueira; Morais, Anna Miethke; Martins, Stella Regina; Santos, Ubiratan de Paula

2012-12-01

The topic of tobacco smoking, in its several aspects, has been receiving increasing attention among researchers over the past few years, which has been reflected in more data and more solid scientific literature on the subject in national journals. This article aims to review the studies that focused on smoking published between January 2010 and June 2012, in Arquivos Brasileiros de Cardiologia (Brazilian Archives of Cardiology), Brazilian Journal of Medical and Biological Research, Clinics (Sao Paulo), Jornal Brasileiro de Pneumologia (Brazilian Journal of Pulmonology), Revista da Associação Médica Brasileira (Journal of the Brazilian Medical Association) and Revista Brasileira de Cirurgia Cardiovascular (Brazilian Journal of Cardiovascular Surgery). During the aforementioned period 58 articles were published, 52 of which were original ones, addressing several aspects of smoking, such as effects on health, epidemiology, cessation and experimental studies.

Methodologies for Verification and Validation of Space Launch System (SLS) Structural Dynamic Models

NASA Technical Reports Server (NTRS)

Coppolino, Robert N.

2018-01-01

Responses to challenges associated with verification and validation (V&V) of Space Launch System (SLS) structural dynamics models are presented in this paper. Four methodologies addressing specific requirements for V&V are discussed. (1) Residual Mode Augmentation (RMA), which has gained acceptance by various principals in the NASA community, defines efficient and accurate FEM modal sensitivity models that are useful in test-analysis correlation and reconciliation and parametric uncertainty studies. (2) Modified Guyan Reduction (MGR) and Harmonic Reduction (HR, introduced in 1976), developed to remedy difficulties encountered with the widely used Classical Guyan Reduction (CGR) method, are presented. MGR and HR are particularly relevant for estimation of "body dominant" target modes of shell-type SLS assemblies that have numerous "body", "breathing" and local component constituents. Realities associated with configuration features and "imperfections" cause "body" and "breathing" mode characteristics to mix resulting in a lack of clarity in the understanding and correlation of FEM- and test-derived modal data. (3) Mode Consolidation (MC) is a newly introduced procedure designed to effectively "de-feature" FEM and experimental modes of detailed structural shell assemblies for unambiguous estimation of "body" dominant target modes. Finally, (4) Experimental Mode Verification (EMV) is a procedure that addresses ambiguities associated with experimental modal analysis of complex structural systems. Specifically, EMV directly separates well-defined modal data from spurious and poorly excited modal data employing newly introduced graphical and coherence metrics.

Experimental and numerical simulation of a rotor/stator interaction event localized on a single blade within an industrial high-pressure compressor

NASA Astrophysics Data System (ADS)

Batailly, Alain; Agrapart, Quentin; Millecamps, Antoine; Brunel, Jean-François

2016-08-01

This contribution addresses a confrontation between the experimental simulation of a rotor/stator interaction case initiated by structural contacts with numerical predictions made with an in-house numerical strategy. Contrary to previous studies carried out within the low-pressure compressor of an aircraft engine, this interaction is found to be non-divergent: high amplitudes of vibration are experimentally observed and numerically predicted over a short period of time. An in-depth analysis of experimental data first allows for a precise characterization of the interaction as a rubbing event involving the first torsional mode of a single blade. Numerical results are in good agreement with experimental observations: the critical angular speed, the wear patterns on the casing as well as the blade dynamics are accurately predicted. Through out the article, the in-house numerical strategy is also confronted to another numerical strategy that may be found in the literature for the simulation of rubbing events: key differences are underlined with respect to the prediction of non-linear interaction phenomena.

An investigation of the mechanisms of calcination and sulfation in coal-water mixtures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Christofides, N.

1990-09-21

The purpose of this investigation is to study the mechanisms of sulfur capture when burning coal-water-limestone mixtures (CWLM) in fluidized beds. Special care is taken to make comparisons with to dry coal and sorbent under comparable experimental conditions. A series of experiments were performed in an eight-inch diameter bubbling fluidized bed combustor to address this problem. 33 refs., 17 figs., 5 tabs.

Individual Differences in False Belief Understanding Are Stable from 3 to 6 Years of Age and Predict Children's Mental State Talk with School Friends

ERIC Educational Resources Information Center

Hughes, Claire; Ensor, Rosie; Marks, Alex

2011-01-01

Despite a wealth of studies in the field, longitudinal assessments of both the stability and predictive utility of individual differences in preschoolers' understanding of the mind remain scarce. To address these gaps, we applied latent variable analyses to (a) experimental data gathered from a socially diverse sample (N = 101, 60 boys and 41…

An Examination of Student Outcomes and Student Satisfaction in a Flipped Learning Environment: A Quasi-Experimental Design

ERIC Educational Resources Information Center

Lee, Angela M.

2016-01-01

Flipped learning has become a hot topic in education, in part because of the media portrayal of flipped learning in existing news stories. Although there has been a rise in popularity and implementation, there has been a lack of empirical research in the field of flipped learning. The purpose of this exploratory study was to address some of the…

An Analysis of the Cost Estimating Process in Air Force Research and Development Laboratories.

DTIC Science & Technology

1981-09-01

inexperienced military or civilian engineer/scientist new to the laboratory environ - ment the cost eatimating dilemma may be especially acute. Problem...several components are subjected to repeated environmental testing. Thus, the data from Question 6 was used to address the first two research questions: 1...Research Scientific study and experimentation directed toward increasing knowledge and understanding in the physical, engineering, environmental , and

Innovative Clinical Trial Designs

PubMed Central

Lavori, Philip W.

2015-01-01

Whereas the 20th-century health care system sometimes seemed to be inhospitable to and unmoved by experimental research, its inefficiency and unaffordability have led to reforms that foreshadow a new health care system. We point out certain opportunities and transformational needs for innovations in study design offered by the 21st-century health care system, and describe some innovative clinical trial designs and novel design methods to address these needs and challenges. PMID:26140056

A Continuum Diffusion Model for Viscoelastic Materials

DTIC Science & Technology

1988-11-01

ZIP Code) 7b. ADDRESS (CJI. Slow, and ZIP Code) Mechanics Div isi on Office of Naval Research; Code 432 Collge Satio, T as 7843800 Quincy Ave. Collge ...these studies, which involved experimental, analytical, and materials science aspects, were conducted by researchers in the fields of physical and...thermodynamics, with irreversibility stemming from the foregoing variables yr through "growth laws" that correspond to viscous resistance. The physical ageing of

Investigation of Rossby-number similarity in the neutral boundary layer using large-eddy simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ohmstede, W.D.; Cederwall, R.T.; Meyers, R.E.

One special case of particular interest, especially to theoreticians, is the steady-state, horizontally homogeneous, autobarotropic (PLB), hereafter referred to as the neutral boundary layer (NBL). The NBL is in fact a 'rare' atmospheric phenomenon, generally associated with high-wind situations. Nevertheless, there is a disproportionate interest in this problem because Rossby-number similarity theory provides a sound approach for addressing this issue. Rossby-number similarity theory has rather wide acceptance, but because of the rarity of the 'true' NBL state, there remains an inadequate experimental database for quantifying constants associated with the Rossby-number similarity concept. Although it remains a controversial issue, it hasmore » been proposed that large-eddy simulation (LES) is an alternative to physical experimentation for obtaining basic atmospherc 'data'. The objective of the study reported here is to investigate Rossby-number similarity in the NBL using LES. Previous studies have not addressed Rossby-number similarity explicitly, although they made use of it in the interpretation of their results. The intent is to calculate several sets of NBL solutions that are ambiguous relative to the their respective Rossby numbers and compare the results for similarity, or the lack of it. 14 refs., 1 fig.« less

The design, implementation, and evaluation of online credit nutrition courses: a systematic review.

PubMed

Cohen, Nancy L; Carbone, Elena T; Beffa-Negrini, Patricia A

2011-01-01

To assess how postsecondary online nutrition education courses (ONEC) are delivered, determine ONEC effectiveness, identify theoretical models used, and identify future research needs. Systematic search of database literature. Postsecondary education. Nine research articles evaluating postsecondary ONEC. Knowledge/performance outcomes and student satisfaction, motivation, or perceptions. Systematic search of 922 articles and review of 9 articles meeting search criteria. Little research regarding ONEC marketing/management existed. Studies primarily evaluated introductory courses using email/websites (before 2000), or course management systems (after 2002). None used true experimental designs; just 3 addressed validity or reliability of measures or pilot-tested instruments. Three articles used theoretical models in course design; few used theories to guide evaluations. Four quasi-experimental studies indicated no differences in nutrition knowledge/performance between online and face-to-face learners. Results were inconclusive regarding student satisfaction, motivation, or perceptions. Students can gain knowledge in online as well as in face-to-face nutrition courses, but satisfaction was mixed. More up-to-date investigations on effective practices are warranted, using theories to identify factors that enhance student outcomes, addressing emerging technologies, and documenting ONEC marketing, management, and delivery. Adequate training/support for faculty is needed to improve student experiences and faculty time management. Copyright © 2011 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.

Stem cell therapy for cardiovascular disease: the demise of alchemy and rise of pharmacology.

PubMed

Jadczyk, T; Faulkner, A; Madeddu, P

2013-05-01

Regenerative medicine holds great promise as a way of addressing the limitations of current treatments of ischaemic disease. In preclinical models, transplantation of different types of stem cells or progenitor cells results in improved recovery from ischaemia. Furthermore, experimental studies indicate that cell therapy influences a spectrum of processes, including neovascularization and cardiomyogenesis as well as inflammation, apoptosis and interstitial fibrosis. Thus, distinct strategies might be required for specific regenerative needs. Nonetheless, clinical studies have so far investigated a relatively small number of options, focusing mainly on the use of bone marrow-derived cells. Rapid clinical translation resulted in a number of small clinical trials that do not have sufficient power to address the therapeutic potential of the new approach. Moreover, full exploitation has been hindered so far by the absence of a solid theoretical framework and inadequate development plans. This article reviews the current knowledge on cell therapy and proposes a model theory for interpretation of experimental and clinical outcomes from a pharmacological perspective. Eventually, with an increased association between cell therapy and traditional pharmacotherapy, we will soon need to adopt a unified theory for understanding how the two practices additively interact for a patient's benefit. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

Analysis of cerebral vessels dynamics using experimental data with missed segments

NASA Astrophysics Data System (ADS)

Pavlova, O. N.; Abdurashitov, A. S.; Ulanova, M. V.; Shihalov, G. M.; Semyachkina-Glushkovskaya, O. V.; Pavlov, A. N.

2018-04-01

Physiological signals often contain various bad segments that occur due to artifacts, failures of the recording equipment or varying experimental conditions. The related experimental data need to be preprocessed to avoid such parts of recordings. In the case of few bad segments, they can simply be removed from the signal and its analysis is further performed. However, when there are many extracted segments, the internal structure of the analyzed physiological process may be destroyed, and it is unclear whether such signal can be used in diagnostic-related studies. In this paper we address this problem for the case of cerebral vessels dynamics. We perform analysis of simulated data in order to reveal general features of quantifying scaling features of complex signals with distinct correlation properties and show that the effects of data loss are significantly different for experimental data with long-range correlations and anti-correlations. We conclude that the cerebral vessels dynamics is significantly less sensitive to missed data fragments as compared with signals with anti-correlated statistics.

Modeling and experimental study on characterization of micromachined thermal gas inertial sensors.

PubMed

Zhu, Rong; Ding, Henggao; Su, Yan; Yang, Yongjun

2010-01-01

Micromachined thermal gas inertial sensors based on heat convection are novel devices that compared with conventional micromachined inertial sensors offer the advantages of simple structures, easy fabrication, high shock resistance and good reliability by virtue of using a gaseous medium instead of a mechanical proof mass as key moving and sensing elements. This paper presents an analytical modeling for a micromachined thermal gas gyroscope integrated with signal conditioning. A simplified spring-damping model is utilized to characterize the behavior of the sensor. The model relies on the use of the fluid mechanics and heat transfer fundamentals and is validated using experimental data obtained from a test-device and simulation. Furthermore, the nonideal issues of the sensor are addressed from both the theoretical and experimental points of view. The nonlinear behavior demonstrated in experimental measurements is analyzed based on the model. It is concluded that the sources of nonlinearity are mainly attributable to the variable stiffness of the sensor system and the structural asymmetry due to nonideal fabrication.

Food abundance does not determine bird use of early-successional habitat

Treesearch

Tracey B. Champlin; John C. Kilgo; Christopher E. Moorman

2009-01-01

Few attempts have been made to experimentally address the extent to which temporal or spatial variation in food availability influences avian habitat use. We used an experimental approach to investigate whether bird use differed between treated (arthropods reduced through insecticide application) and control (untreated) forest canopy gaps within a bottomland hardwood...

Brief Experimental Analysis of Written Letter Formation: Single-Case Demonstration

ERIC Educational Resources Information Center

Burns, Matthew K.; Ganuza, Zoila M.; London, Rachel M.

2009-01-01

Many students experience difficulty in acquiring basic writing skills and educators need to efficiently address those deficits by implementing an intervention with a high likelihood for success. The current article demonstrates the utility of using a brief experimental analysis (BEA) to identify a letter-formation intervention for a second-grade…

Lab Notebooks as Scientific Communication: Investigating Development from Undergraduate Courses to Graduate Research

ERIC Educational Resources Information Center

Stanley, Jacob T.; Lewandowski, H. J.

2016-01-01

In experimental physics, lab notebooks play an essential role in the research process. For all of the ubiquity of lab notebooks, little formal attention has been paid to addressing what is considered "best practice" for scientific documentation and how researchers come to learn these practices in experimental physics. Using interviews…

"The Women's Room": An Experimental Mixed Media Production.

ERIC Educational Resources Information Center

Kizer, Elizabeth; Burns, Gary

The novel "The Women's Room," by Marilyn French, deserves an audience both because of the timely feminist issues it addresses and because of its formal experimentation with points of view. An interpretive theatre version of the story was performed twice in 1982-83, using a script adapted from the novel, and a modified chamber theatre…

Range management research, Fort Valley Experimental Forest

Treesearch

Henry A. Pearson; Warren P. Clary; Margaret M. Moore; Carolyn Hull Sieg

2008-01-01

Range management research at the Fort Valley Experimental Forest during the past 100 years has provided scientific knowledge for managing ponderosa pine forests and forest-range grazing lands in the Southwest. Three research time periods are identified: 1908 to 1950, 1950 to 1978, and 1978 to 2008. Early research (1908-1950) addressed ecological effects of livestock...

Experimental entanglement of 25 individually accessible atomic quantum interfaces

PubMed Central

Jiang, Nan; Chang, Wei; Li, Chang; Zhang, Sheng

2018-01-01

A quantum interface links the stationary qubits in a quantum memory with flying photonic qubits in optical transmission channels and constitutes a critical element for the future quantum internet. Entanglement of quantum interfaces is an important step for the realization of quantum networks. Through heralded detection of photon interference, we generate multipartite entanglement between 25 (or 9) individually addressable quantum interfaces in a multiplexed atomic quantum memory array and confirm genuine 22-partite (or 9-partite) entanglement. This experimental entanglement of a record-high number of individually addressable quantum interfaces makes an important step toward the realization of quantum networks, long-distance quantum communication, and multipartite quantum information processing. PMID:29725621

Achilles tendinosis – a morphometrical study in a rat model

PubMed Central

Silva, Rafael Duarte; Glazebrook, Mark Anthony; Campos, Vinicius Castro; Vasconcelos, Anilton Cesar

2011-01-01

This study addresses the morphopathogenesis of Achilles tendinosis, using a rat model and presenting quantitative analysis of time-dependent histological changes. Thirty Wistar rats were used, randomly split in experimental and control groups. Animals of the experimental group were submitted to a treadmill running scheme. Five animals of each group were euthanized at four, eight and sixteen weeks. Achilles tendons were collected and processed routinely for histopath sections. Slides were stained by Hematoxylin-Eosin, Picrosirius Red, Alcian Blue, AgNOR, TUNEL and evaluated morphometrically. Cellular density decreased slightly along the time and was higher in the experimental group than in controls at fourth, eighth and sixteenth weeks. Fiber microtearing, percentual of reticular fibers and glycosaminoglycans content increased along the time and were higher in experimental group than in controls at all-time intervals. AgNOR labeling here interpreted as a marker of transcription activity was higher in the experimental groups than in controls at all-time intervals. Apoptotic cells were more frequent and diffusely distributed in tendinosis samples than in control groups. These results suggest that as mechanical overload is becoming chronic, cellular turnover and matrix deposition increases leading to tendinosis. The combination of staining techniques and morphometry used here to describe the evolution of lesions occurring in a rat model system has proved to be suited for the study of induced Achilles tendinosis. PMID:22076169

Influence of disorder on electromagnetically induced transparency in chiral waveguide quantum electrodynamics

NASA Astrophysics Data System (ADS)

Mirza, Imran M.; Schotland, John C.

2018-05-01

We study single photon transport in a one-dimensional disordered lattice of three-level atoms coupled to an optical waveguide. In particular, we study atoms of \\Lambda-type that are capable of exhibiting electromagnetically induced transparency (EIT) and separately consider disorder in the atomic positions and transition frequencies. We mainly address the question of how preferential emission into waveguide modes (chirality) can influence the formation of spatially localized states. Our work has relevance to experimental studies of cold atoms coupled to nanoscale waveguides and has possible applications to quantum communications.

Federal research and development for satellite communications

NASA Technical Reports Server (NTRS)

1977-01-01

A Committee on Satellite Communication (COSC) was formed under the auspices of the Space Applications Board (SAB) in order to study Federal research and development on satellite communications (SC). Discussion on whether to continue the research and development and the proper role of the Federal Government are addressed. Discussion focussed on six possible options for a Federal role in SC research and development: (1) the current NASA SC program; (2) an expanded NASA SC technology program; (3) a SC technology flight test support program; (4) an experimental SC technology flight program; (5) an experimental public service SC system program; and (6) an operational public service SC system program. Decision criteria and recommendations are presented.

Experimental gingivitis, bacteremia and systemic biomarkers: a randomized clinical trial.

PubMed

Kinane, D F; Zhang, P; Benakanakere, M; Singleton, J; Biesbrock, A; Nonnenmacher, C; He, T

2015-12-01

Bacteremia and systemic inflammatory markers are associated with periodontal and systemic diseases and may be linking mechanisms between these conditions. We hypothesized that in the development of gingival inflammation, systemic markers of inflammation and bacteremia would increase. To study the effect of bacteremia on systemic inflammatory markers, we recruited 80 subjects to participate in an experimental gingivitis study. Subjects were stratified based on gender, smoking and the number of bleeding sites and then randomized to one of two groups: control group (n = 40) or experimental gingivitis group (n = 40). Subjects in the control group conducted an oral hygiene regimen: brushing twice daily with a regular sodium fluoride cavity protection dentifrice and a standard manual toothbrush, flossing twice daily, and mouth rinsing with an anti-cavity fluoride rinse once daily. The experimental group stopped brushing and flossing, and used only the fluoride anti-cavity mouth rinse for 21 d. Seventy-nine of 80 subjects were evaluable. One subject in the control group was excluded from the results due to antibiotic use during the study. Our data showed the experimental gingivitis group exhibited a significant (p < 0.05) increase in dental plaque level and gingival inflammatory indices relative to baseline and the control group but a decrease in bacteremia and soluble intercellular adhesion molecule-1 levels vs. baseline. Bacteremia was negatively correlated with gingival inflammatory indices and soluble intercellular adhesion molecule-1 levels in the experimental gingivitis group, thus negating our hypothesis. We conclude that there are marked differences in systemic cytokine levels over the course of short-term experimentally induced gingivitis and further conclude that a long-term periodontitis study must be considered to address mechanisms whereby oral diseases may affect systemic diseases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Are There Multiple Kinds of Episodic Memory? An fMRI Investigation Comparing Autobiographical and Recognition Memory Tasks.

PubMed

Chen, Hung-Yu; Gilmore, Adrian W; Nelson, Steven M; McDermott, Kathleen B

2017-03-08

What brain regions underlie retrieval from episodic memory? The bulk of research addressing this question with fMRI has relied upon recognition memory for materials encoded within the laboratory. Another, less dominant tradition has used autobiographical methods, whereby people recall events from their lifetime, often after being cued with words or pictures. The current study addresses how the neural substrates of successful memory retrieval differed as a function of the targeted memory when the experimental parameters were held constant in the two conditions (except for instructions). Human participants studied a set of scenes and then took two types of memory test while undergoing fMRI scanning. In one condition (the picture memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it was recollected from the prior study episode. In a second condition (the life memory test), participants reported for each scene (32 studied, 64 nonstudied) whether it reminded them of a specific event from their preexperimental lifetime. An examination of successful retrieval (yes responses) for recently studied scenes for the two test types revealed pronounced differences; that is, autobiographical retrieval instantiated with the life memory test preferentially activated the default mode network, whereas hits in the picture memory test preferentially engaged the parietal memory network as well as portions of the frontoparietal control network. When experimental cueing parameters are held constant, the neural underpinnings of successful memory retrieval differ when remembering life events and recently learned events. SIGNIFICANCE STATEMENT Episodic memory is often discussed as a solitary construct. However, experimental traditions examining episodic memory use very different approaches, and these are rarely compared to one another. When the neural correlates associated with each approach have been directly contrasted, results have varied considerably and at times contradicted each other. The present experiment was designed to match the two primary approaches to studying episodic memory in an unparalleled manner. Results suggest a clear separation of systems supporting memory as it is typically tested in the laboratory and memory as assessed under autobiographical retrieval conditions. These data provide neurobiological evidence that episodic memory is not a single construct, challenging the degree to which different experimental traditions are studying the same construct. Copyright © 2017 the authors 0270-6474/17/372764-12$15.00/0.

Pharmacological Strategies to Retard Cardiovascular Aging.

PubMed

Alfaras, Irene; Di Germanio, Clara; Bernier, Michel; Csiszar, Anna; Ungvari, Zoltan; Lakatta, Edward G; de Cabo, Rafael

2016-05-13

Aging is the major risk factor for cardiovascular diseases, which are the leading cause of death in the United States. Traditionally, the effort to prevent cardiovascular disease has been focused on addressing the conventional risk factors, including hypertension, hyperglycemia, hypercholesterolemia, and high circulating levels of triglycerides. However, recent preclinical studies have identified new approaches to combat cardiovascular disease. Calorie restriction has been reproducibly shown to prolong lifespan in various experimental model animals. This has led to the development of calorie restriction mimetics and other pharmacological interventions capable to delay age-related diseases. In this review, we will address the mechanistic effects of aging per se on the cardiovascular system and focus on the prolongevity benefits of various therapeutic strategies that support cardiovascular health. © 2016 American Heart Association, Inc.

Pharmacological Strategies to Retard Cardiovascular Aging

PubMed Central

Alfaras, Irene; Di Germanio, Clara; Bernier, Michel; Csiszar, Anna; Ungvari, Zoltan; Lakatta, Edward G.; de Cabo, Rafael

2016-01-01

Aging is the major risk factor for cardiovascular diseases (CVD), which are the leading cause of death in the United States. Traditionally, the effort to prevent CVD has been focused on addressing the conventional risk factors, including hypertension, hyperglycemia, hypercholesterolemia, and high circulating levels of triglycerides. However, recent preclinical studies have identified new approaches to combat CVD. Calorie restriction has been reproducibly shown to prolong lifespan in various experimental model animals. This has led to the development of calorie restriction mimetics and other pharmacological interventions capable to delay age-related diseases. In this review, we will address the mechanistic effects of aging per se on the cardiovascular system and focus on the pro-longevity benefits of various therapeutic strategies that support cardiovascular health. PMID:27174954

Modeling Gene-Environment Interactions With Quasi-Natural Experiments.

PubMed

Schmitz, Lauren; Conley, Dalton

2017-02-01

This overview develops new empirical models that can effectively document Gene × Environment (G×E) interactions in observational data. Current G×E studies are often unable to support causal inference because they use endogenous measures of the environment or fail to adequately address the nonrandom distribution of genes across environments, confounding estimates. Comprehensive measures of genetic variation are incorporated into quasi-natural experimental designs to exploit exogenous environmental shocks or isolate variation in environmental exposure to avoid potential confounders. In addition, we offer insights from population genetics that improve upon extant approaches to address problems from population stratification. Together, these tools offer a powerful way forward for G×E research on the origin and development of social inequality across the life course. © 2015 Wiley Periodicals, Inc.

Community-Based Participatory Research to Promote Healthy Diet and Nutrition and Prevent and Control Obesity Among African-Americans: a Literature Review.

PubMed

Coughlin, Steven S; Smith, Selina A

2017-04-01

The literature on community-based participatory research (CBPR) approaches for promoting healthy diet and nutrition and preventing and controlling obesity in African-American communities was systematically reviewed as part of the planning process for new research. CBPR studies of diet, nutrition, and weight management among African-Americans were identified from 1989 through October 31, 2015, using PubMed and the Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases and MeSH term and keyword searches. A total of 16 CBPR studies on healthy diet, nutrition, and weight management among African-Americans were identified; outcome evaluation results were available for all but two. Of the remaining 14 studies, 11 focused on adults, 1 on children, and 2 on both children and adults. Eight studies employed CBPR methods to address diet, nutrition, and weight management in church settings. Four had a cluster-randomized controlled design. Others had a pre-post test, quasi-experimental, or uncontrolled design. Only one study addressed four levels of the socioecological model; none addressed all five levels of the model. The studies identified in this review indicate that CBPR approaches can be effective for promoting healthy diet, nutrition, and weight management among African-American adults, but there is a need for additional studies with rigorous study designs that overcome methodologic limitations of many existing studies. There is only limited evidence for the effectiveness of CBPR approaches for promoting healthy eating and weight control among African-American children and adolescents. To address health disparities, additional CBPR studies are needed to promote healthy diet, nutrition, and weight management in African-American communities. Of particular interest are multilevel CBPR studies that include interventions aimed at multiple levels of the socioecological model.

Clinical trials of drugs from the viewpoint of the academic investigator (a satire).

PubMed

Lasagna, L

1975-11-01

Dr. Lasagna was unable to attend the workshop in person, and therefore delivered his remarks by videotape, in the assumed role of the newest "Secretary of Human Experimentation" at the Department of Health, Education, and Welfare addressing a public television audience. There is no difficulty in sensing the serious truths underlying the satire in his address.

A New Kind of Laser Microphone for Photoacoustic Applications

DTIC Science & Technology

2008-12-01

1 A NEW KIND OF LASER MICROPHONE FOR PHOTOACOUSTIC APPLICATIONS Chen-Chia Wang, Sudhir Trivedi, and Feng Jin Brimrose ...NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Brimrose Corp. of America, 7720 Belair Road...laser microphone’s performance are also developed with preliminary experimental validation. ACKONWLEDGMENTS The authors from Brimrose

Long-Term Environmental Research Programs - Evolving Capacity for Discovery

NASA Astrophysics Data System (ADS)

Swanson, F. J.

2008-12-01

Long-term forestry, watershed, and ecological research sites have become critical, productive nodes for environmental science research and in some cases for work in the social sciences and humanities. The Forest Service's century-old Experimental Forests and Ranges and the National Science Foundation's 28- year-old Long-Term Ecological Research program have been remarkably productive in both basic and applied sciences, including characterization of acid rain and old-growth ecosystems and development of forest, watershed, and range management systems for commercial and other land use objectives. A review of recent developments suggests steps to enhance the function of collections of long-term research sites as interactive science networks. The programs at these sites have evolved greatly, especially over the past few decades, as the questions addressed, disciplines engaged, and degree of science integration have grown. This is well displayed by small, experimental watershed studies, which first were used for applied hydrology studies then more fundamental biogeochemical studies and now examination of complex ecosystem processes; all capitalizing on the legacy of intensive studies and environmental monitoring spanning decades. In very modest ways these collections of initially independent sites have functioned increasingly as integrated research networks addressing inter-site questions by using common experimental designs, being part of a single experiment, and examining long-term data in a common analytical framework. The network aspects include data sharing via publicly-accessible data-harvester systems for climate and streamflow data. The layering of one research or environmental monitoring network upon another facilitates synergies. Changing climate and atmospheric chemistry highlight a need to use these networks as continental-scale observatory systems for assessing the impacts of environmental change on ecological services. To better capitalize on long-term research sites and networks, agencies and universities 1) need to encourage collaboration among sites and between science and land manager communities while 2) maintaining long- term studies and monitoring efforts, and staffing the collaboration in each partner organization, including positions specifically designated as liaisons among the participating communities.

Design and analysis issues in quantitative proteomics studies.

PubMed

Karp, Natasha A; Lilley, Kathryn S

2007-09-01

Quantitative proteomics is the comparison of distinct proteomes which enables the identification of protein species which exhibit changes in expression or post-translational state in response to a given stimulus. Many different quantitative techniques are being utilized and generate large datasets. Independent of the technique used, these large datasets need robust data analysis to ensure valid conclusions are drawn from such studies. Approaches to address the problems that arise with large datasets are discussed to give insight into the types of statistical analyses of data appropriate for the various experimental strategies that can be employed by quantitative proteomic studies. This review also highlights the importance of employing a robust experimental design and highlights various issues surrounding the design of experiments. The concepts and examples discussed within will show how robust design and analysis will lead to confident results that will ensure quantitative proteomics delivers.

Phenomenological study of decoherence in solid-state spin qubits due to nuclear spin diffusion

NASA Astrophysics Data System (ADS)

Biercuk, Michael J.; Bluhm, Hendrik

2011-06-01

We present a study of the prospects for coherence preservation in solid-state spin qubits using dynamical decoupling protocols. Recent experiments have provided the first demonstrations of multipulse dynamical decoupling sequences in this qubit system, but quantitative analyses of potential coherence improvements have been hampered by a lack of concrete knowledge of the relevant noise processes. We present calculations of qubit coherence under the application of arbitrary dynamical decoupling pulse sequences based on an experimentally validated semiclassical model. This phenomenological approach bundles the details of underlying noise processes into a single experimentally relevant noise power spectral density. Our results show that the dominant features of experimental measurements in a two-electron singlet-triplet spin qubit can be replicated using a 1/ω2 noise power spectrum associated with nuclear spin flips in the host material. Beginning with this validation, we address the effects of nuclear programming, high-frequency nuclear spin dynamics, and other high-frequency classical noise sources, with conjectures supported by physical arguments and microscopic calculations where relevant. Our results provide expected performance bounds and identify diagnostic metrics that can be measured experimentally in order to better elucidate the underlying nuclear spin dynamics.

TummyTrials: A Feasibility Study of Using Self-Experimentation to Detect Individualized Food Triggers.

PubMed

Karkar, Ravi; Schroeder, Jessica; Epstein, Daniel A; Pina, Laura R; Scofield, Jeffrey; Fogarty, James; Kientz, Julie A; Munson, Sean A; Vilardaga, Roger; Zia, Jasmine

2017-05-02

Diagnostic self-tracking, the recording of personal information to diagnose or manage a health condition, is a common practice, especially for people with chronic conditions. Unfortunately, many who attempt diagnostic self-tracking have trouble accomplishing their goals. People often lack knowledge and skills needed to design and conduct scientifically rigorous experiments, and current tools provide little support. To address these shortcomings and explore opportunities for diagnostic self-tracking, we designed, developed, and evaluated a mobile app that applies a self-experimentation framework to support patients suffering from irritable bowel syndrome (IBS) in identifying their personal food triggers. TummyTrials aids a person in designing, executing, and analyzing self-experiments to evaluate whether a specific food triggers their symptoms. We examined the feasibility of this approach in a field study with 15 IBS patients, finding that participants could use the tool to reliably undergo a self-experiment. However, we also discovered an underlying tension between scientific validity and the lived experience of self-experimentation. We discuss challenges of applying clinical research methods in everyday life, motivating a need for the design of self-experimentation systems to balance rigor with the uncertainties of everyday life.

Segmentation of large periapical lesions toward dental computer-aided diagnosis in cone-beam CT scans

NASA Astrophysics Data System (ADS)

Rysavy, Steven; Flores, Arturo; Enciso, Reyes; Okada, Kazunori

2008-03-01

This paper presents an experimental study for assessing the applicability of general-purpose 3D segmentation algorithms for analyzing dental periapical lesions in cone-beam computed tomography (CBCT) scans. In the field of Endodontics, clinical studies have been unable to determine if a periapical granuloma can heal with non-surgical methods. Addressing this issue, Simon et al. recently proposed a diagnostic technique which non-invasively classifies target lesions using CBCT. Manual segmentation exploited in their study, however, is too time consuming and unreliable for real world adoption. On the other hand, many technically advanced algorithms have been proposed to address segmentation problems in various biomedical and non-biomedical contexts, but they have not yet been applied to the field of dentistry. Presented in this paper is a novel application of such segmentation algorithms to the clinically-significant dental problem. This study evaluates three state-of-the-art graph-based algorithms: a normalized cut algorithm based on a generalized eigen-value problem, a graph cut algorithm implementing energy minimization techniques, and a random walks algorithm derived from discrete electrical potential theory. In this paper, we extend the original 2D formulation of the above algorithms to segment 3D images directly and apply the resulting algorithms to the dental CBCT images. We experimentally evaluate quality of the segmentation results for 3D CBCT images, as well as their 2D cross sections. The benefits and pitfalls of each algorithm are highlighted.

A new scenario-based approach to damage detection using operational modal parameter estimates

NASA Astrophysics Data System (ADS)

Hansen, J. B.; Brincker, R.; López-Aenlle, M.; Overgaard, C. F.; Kloborg, K.

2017-09-01

In this paper a vibration-based damage localization and quantification method, based on natural frequencies and mode shapes, is presented. The proposed technique is inspired by a damage assessment methodology based solely on the sensitivity of mass-normalized experimental determined mode shapes. The present method differs by being based on modal data extracted by means of Operational Modal Analysis (OMA) combined with a reasonable Finite Element (FE) representation of the test structure and implemented in a scenario-based framework. Besides a review of the basic methodology this paper addresses fundamental theoretical as well as practical considerations which are crucial to the applicability of a given vibration-based damage assessment configuration. Lastly, the technique is demonstrated on an experimental test case using automated OMA. Both the numerical study as well as the experimental test case presented in this paper are restricted to perturbations concerning mass change.

Justice- and fairness-related behaviors in nonhuman primates.

PubMed

Brosnan, Sarah F

2013-06-18

A distinctive feature across human societies is our interest in justice and fairness. People will sometimes invest in extremely costly behavior to achieve fair outcomes for themselves and others. Why do people care so much about justice? One way to address this is comparatively, exploring behaviors related to justice and fairness in other species. In this paper, I review work exploring responses to inequity, prosocial behavior, and other relevant behaviors in nonhuman primates in an effort to understand both the potential evolutionary function of these behaviors and the social and ecological reasons for the individual differences in behavior. I also consider how these behaviors relate to human behavior, particularly in the case of experimental studies using games derived from experimental economics to compare nonhuman primates' responses to those of humans in similar experimental conditions. These results emphasize the importance of a comparative approach to better understand the function and diversity of human behavior.

The fluid transport in inkjet-printed liquid rivulets

NASA Astrophysics Data System (ADS)

Singler, Timothy; Liu, Liang; Sun, Xiaoze; Pei, Yunheng; Microfluidic; Interfacial Transport Lab Team

2017-11-01

Inkjet printing holds significant potential for the controlled deposition of solution-processed functional materials spanning applications from microelectronics to biomedical sciences. Although theoretical and experimental investigations addressing the stability criteria of the inkjet-printed liquid rivulets have been discussed in the literature, the associated transport phenomena have received little attention. This study focuses on the experimental investigation of printed rivulets, stable with respect to Rayleigh-Plateau, but exhibiting bulge instability. The morphological evolution and the depth-resolved flow field of the rivulets were assessed via high-speed imaging in conjunction with micro-PIV. We discuss in detail effects of repetitive wave motion induced by periodic drop impact at the leading edge and the associated pulsatile flow, as well as the persistent nonuniform mass distribution in the ridge region of the rivulet. The results provide an experimental foundation for more detailed theoretical modelling of printed rivulet flows.

Examining the Relationships Between Education, Social Networks and Democratic Support With ABM

NASA Technical Reports Server (NTRS)

Drucker, Nick; Campbell, Kenyth

2011-01-01

This paper introduces an agent-based model that explores the relationships between education, social networks, and support for democratic ideals. This study examines two factors thai affect democratic support, education, and social networks. Current theory concerning these two variables suggests that positive relationships exist between education and democratic support and between social networks and the spread of ideas. The model contains multiple variables of democratic support, two of which are evaluated through experimentation. The model allows individual entities within the system to make "decisions" about their democratic support independent of one another. The agent based approach also allows entities to utilize their social networks to spread ideas. Current theory supports experimentation results. In addion , these results show the model is capable of reproducing real world outcomes. This paper addresses the model creation process and the experimentation procedure, as well as future research avenues and potential shortcomings of the model

Justice- and fairness-related behaviors in nonhuman primates

PubMed Central

Brosnan, Sarah F.

2013-01-01

A distinctive feature across human societies is our interest in justice and fairness. People will sometimes invest in extremely costly behavior to achieve fair outcomes for themselves and others. Why do people care so much about justice? One way to address this is comparatively, exploring behaviors related to justice and fairness in other species. In this paper, I review work exploring responses to inequity, prosocial behavior, and other relevant behaviors in nonhuman primates in an effort to understand both the potential evolutionary function of these behaviors and the social and ecological reasons for the individual differences in behavior. I also consider how these behaviors relate to human behavior, particularly in the case of experimental studies using games derived from experimental economics to compare nonhuman primates’ responses to those of humans in similar experimental conditions. These results emphasize the importance of a comparative approach to better understand the function and diversity of human behavior. PMID:23754407

Associations of ozone and PM2.5 concentrations with Parkinson’s disease among participants in the Agricultural Health Study

PubMed Central

Bowman, Christal; Davis, J. Allen; Hoppin, Jane A.; Blair, Aaron; Chen, Honglei; Patel, Molini M.; Sandler, Dale P.; Tanner, Caroline M.; Vinikoor-Imler, Lisa; Ward, Mary H.; Luben, Thomas J.; Kamel, Freya

2015-01-01

Objective This study describes associations of ozone and fine particulate matter with Parkinson’s disease observed among farmers in North Carolina and Iowa. Methods We used logistic regression to determine the associations of these pollutants with self-reported, doctor-diagnosed Parkinson’s disease. Daily predicted pollutant concentrations were used to derive surrogates of long-term exposure and link them to study participants’ geocoded addresses. Results We observed positive associations of Parkinson’s disease with ozone (OR=1.39; 95% CI: 0.98, 1.98) and fine particulate matter (OR=1.34; 95% CI: 0.93, 1.93) in North Carolina but not in Iowa. Conclusion The plausibility of an effect of ambient concentrations of these pollutants on Parkinson’s disease risk is supported by experimental data demonstrating damage to dopaminergic neurons at relevant concentrations. Additional studies are needed to address uncertainties related to confounding and to examine temporal aspects of the associations we observed. PMID:25951420

Vibro-acoustic modelling of aircraft double-walls with structural links using Statistical Energy Analysis

NASA Astrophysics Data System (ADS)

Campolina, Bruno L.

The prediction of aircraft interior noise involves the vibroacoustic modelling of the fuselage with noise control treatments. This structure is composed of a stiffened metallic or composite panel, lined with a thermal and acoustic insulation layer (glass wool), and structurally connected via vibration isolators to a commercial lining panel (trim). The goal of this work aims at tailoring the noise control treatments taking design constraints such as weight and space optimization into account. For this purpose, a representative aircraft double-wall is modelled using the Statistical Energy Analysis (SEA) method. Laboratory excitations such as diffuse acoustic field and point force are addressed and trends are derived for applications under in-flight conditions, considering turbulent boundary layer excitation. The effect of the porous layer compression is firstly addressed. In aeronautical applications, compression can result from the installation of equipment and cables. It is studied analytically and experimentally, using a single panel and a fibrous uniformly compressed over 100% of its surface. When compression increases, a degradation of the transmission loss up to 5 dB for a 50% compression of the porous thickness is observed mainly in the mid-frequency range (around 800 Hz). However, for realistic cases, the effect should be reduced since the compression rate is lower and compression occurs locally. Then the transmission through structural connections between panels is addressed using a four-pole approach that links the force-velocity pair at each side of the connection. The modelling integrates experimental dynamic stiffness of isolators, derived using an adapted test rig. The structural transmission is then experimentally validated and included in the double-wall SEA model as an equivalent coupling loss factor (CLF) between panels. The tested structures being flat, only axial transmission is addressed. Finally, the dominant sound transmission paths are identified in the 100 Hz to 10 kHz frequency range for double-walls under diffuse acoustic field and under point-force excitations. Non-resonant transmission is higher at low frequencies (frequencies lower than 1 kHz) while the structure-borne and the airborne paths dominate at mid- and high-frequencies, around 1 kHz and higher, respectively. An experimental validation on double-walls shows that the model is able to predict changes in the overall transmission caused by different structural couplings (rigid coupling, coupling via isolators and structurally uncoupled). Noise reduction means adapted to each transmission path, such as absorption, dissipation and structural decoupling, may be then derived. Keywords: Statistical energy analysis, Vibration isolator, Double-wall, Transfer path analysis, Transmission Loss.

Experimental evaluation of candidate graphical microburst alert displays

NASA Technical Reports Server (NTRS)

Wanke, Craig; Hansman, R. John

1992-01-01

The topics addressed are: (1) experimental evaluation of candidate graphical microburst displays; (2) microburst detection and alerting; (3) previous part-task simulator experiment-comparison of presentation modes; (4) presentation mode comparison-results; (5) advantages of graphical mode of presentation; (6) graphical microburst alert experiment-objectives; and graphical microburst alert experiment-overview; and (7) candidate display design.

Research related to roads in USDA experimental forests [Chapter 16

Treesearch

W. J. Elliot; P. J. Edwards; R. B. Foltz

2014-01-01

Forest roads are essential in experimental forests and rangelands (EFRs) to allow researchers and the public access to research sites and for fire suppression, timber extraction, and fuel management. Sediment from roads can adversely impact watershed health. Since the 1930s, the design and management of forest roads has addressed both access issues and watershed health...

Range management research, Fort Valley Experimental Forest (P-53)

Treesearch

Henry A. Pearson; Warren P. Clary; Margaret M. Moore; Carolyn Hull Sieg

2008-01-01

Range management research at the Fort Valley Experimental Forest during the past 100 years has provided scientific knowledge for managing ponderosa pine forests and forest-range grazing lands in the Southwest. Three research timeperiods are identified: 1908 to 1950, 1950 to 1978, and 1978 to 2008. Early research (1908-1950) addressed ecological effects of livestock...

An Experimental Model for Analyzing Strategies for Financing Higher Education in New York State.

ERIC Educational Resources Information Center

New York State Education Dept., Albany. Office of Postsecondary Research, Information Systems, and Institutional Aid.

Described is an experimental, quantitative model developed by the New York State Education Department to evaluate state-level financing strategies for higher education. It can be used to address a variety of questions and takes into account a host of direct and indirect relationships. It uses computer software and optimization algorithms developed…

Random domain name and address mutation (RDAM) for thwarting reconnaissance attacks

PubMed Central

Chen, Xi; Zhu, Yuefei

2017-01-01

Network address shuffling is a novel moving target defense (MTD) that invalidates the address information collected by the attacker by dynamically changing or remapping the host’s network addresses. However, most network address shuffling methods are limited by the limited address space and rely on the host’s static domain name to map to its dynamic address; therefore these methods cannot effectively defend against random scanning attacks, and cannot defend against an attacker who knows the target’s domain name. In this paper, we propose a network defense method based on random domain name and address mutation (RDAM), which increases the scanning space of the attacker through a dynamic domain name method and reduces the probability that a host will be hit by an attacker scanning IP addresses using the domain name system (DNS) query list and the time window methods. Theoretical analysis and experimental results show that RDAM can defend against scanning attacks and worm propagation more effectively than general network address shuffling methods, while introducing an acceptable operational overhead. PMID:28489910

Difficulties in the neuroscience of creativity: jazz improvisation and the scientific method.

PubMed

McPherson, Malinda; Limb, Charles J

2013-11-01

Creativity is a fundamental and remarkable human capacity, yet the scientific study of creativity has been limited by the difficulty of reconciling the scientific method and creative processes. We outline several hurdles and considerations that should be addressed when studying the cognitive neuroscience of creativity and suggest that jazz improvisation may be one of the most useful experimental models for the study of spontaneous creativity. More broadly, we argue that studying creativity in a way that is both scientifically and ecologically valid requires collaboration between neuroscientists and artists. © 2013 New York Academy of Sciences.

Photon Strength Function at Low Energies in 95Mo

DOE PAGES

Wiedeking, M.; Bernstein, L. A.; Allmond, J. M.; ...

2014-05-01

A new and model-independent experimental method has been developed to determine the energy dependence of the photon strength function. It is designed to study statistical feeding from the quasi continuum to individual low-lying discrete levels. This new technique is presented and results for 95Mo are compared to data from the University of Oslo. In particular, questions regarding the existence of the low-energy enhancement in the photon strength function are addressed.

Theory of Collective Spin-Wave Modes of Interacting Ferromagnetic Spheres

DTIC Science & Technology

2004-09-29

Office (Durham) through Contract No. CS0001028. R. A. thanks also Proyecto Fondecyt Grant No. 7030063. *Present address: Universidad de Chile...Departamento de Fisica FCFM, Santiago, Chile. 1 For examples of experimental studies of the collective spin wave modes of superlattices and multilayers, see M...character to those shown above. In this case, there is no simple symmetry de - composition one canmake for the collective modes, so all branches appear

Two Week Oral Dose Range-Finding Toxicity Study of WR242511 in Rats

DTIC Science & Technology

1993-07-08

Express Clinical Chemistry System IFCC, Committee on Standards, Part 2. IFCC Method for Aspartate Aminotransferase, Amsterdam, Elsevier Scientific...PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER DAM017-92-C-2OO1 8c ADDRESS (City, State, and ZIP Code) Fort Detrick Frederick, MO 21702-5009 10. SOURCE...7 2. INTRODUCTION 7 3. MATERIALS AND METHODS 7 3.1 Test Article 7 3.2 Animals 8 3.3 Experimental Design 8 3.4

Mammalian Toxicology Testing: Problem Definition Study, AMTR Protocol/Pricing Report.

DTIC Science & Technology

1981-04-01

62777A. 3E162777A878.CC.208 Cleveland, OH 44122 11. CONTROLLING OFFICE NAME AND ADDRESS 12. REPORT DATE US Army Medical Research and Development...grouped according to showing fiuc, eft;. . ur microscopically. experimental groups. and the non - abnormality. (A) In the control and highest dose...every lesion in the animal. Non -neoolastic lesions which are ob- served frequently or which are common in both treated and control animals should be

Ultimate Gradient Limitation in Niobium Superconducting Accelerating Cavities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Checchin, Mattia; Grassellino, Anna; Martinello, Martina

2016-06-01

The present study is addressed to the theoretical description of the ultimate gradient limitation in SRF cavities. Our intent is to exploit experimental data to confirm models which provide feed-backs on how to improve the current state-of-art. New theoretical insight on the cavities limiting factor can be suitable to improve the quench field of N-doped cavities, and therefore to take advantage of high Q 0 at high gradients.

Understanding Medicaid Managed Care Investments in Members' Social Determinants of Health.

PubMed

Gottlieb, Laura; Ackerman, Sara; Wing, Holly; Manchanda, Rishi

2017-08-01

Despite widespread interest in addressing social determinants of health (SDH) as a means to improve health and to reduce health care spending, little information is available about how to develop, sustain, and scale nonmedical interventions in diverse payer environments, including Medicaid Managed Care. This study aimed to explore how Medicaid Managed Care Organization (MMCO) leaders interpret their roles and responsibilities around SDH, how they garner resources to develop and sustain interventions to address SDH, and how they perceive the influences of external organizations on related activities. Semistructured qualitative key informant interviews were conducted with a purposive sample of 26 Medicaid Managed Care corporate executives. Data were analyzed with an iterative coding, thematic development and interpretation process. MMCO leaders' interests and activities around interventions to address SDH are described, as well as their perceptions of existing and potential incentives and barriers to expanding these interventions. Despite significant experimentation and programmatic diversity of interventions addressing social determinants, MMCO leaders struggle with clinical integration, financing, and evaluation efforts that could promote sustainability. Though their efforts are nascent, MMCO leaders are investing in tackling social determinants to improve health and to decrease health care spending in managed care settings that serve low-income populations. Results highlight both opportunities and concerns about sustaining and scaling clinical interventions addressing SDH.

Ortho and para hydrogen dimers on G/SiC(0001): combined STM and DFT study.

PubMed

Merino, P; Švec, M; Martínez, J I; Mutombo, P; Gonzalez, C; Martín-Gago, J A; de Andres, P L; Jelinek, P

2015-01-01

The hydrogen (H) dimer structures formed upon room-temperature H adsorption on single layer graphene (SLG) grown on SiC(0001) are addressed using a combined theoretical-experimental approach. Our study includes density functional theory (DFT) calculations for the full (6√3 × 6√3)R30° unit cell of the SLG/SiC(0001) substrate and atomically resolved scanning tunneling microscopy images determining simultaneously the graphene lattice and the internal structure of the H adsorbates. We show that H atoms normally group in chemisorbed coupled structures of different sizes and orientations. We make an atomic scale determination of the most stable experimental geometries, the small dimers and ellipsoid-shaped features, and we assign them to hydrogen adsorbed in para dimers and ortho dimers configuration, respectively, through comparison with the theory.

Stereoscopy in Astronomical Visualizations to Support Learning at Informal Education Settings

NASA Astrophysics Data System (ADS)

Price, Aaron; Lee, Hee-Sun

2015-08-01

Stereoscopy has been used in science education for 100 years. Recent innovations in low cost technology as well as trends in the entertainment industry have made stereoscopy popular among educators and audiences alike. However, experimental studies addressing whether stereoscopy actually impacts science learning are limited. Over the last decade, we have conducted a series of quasi-experimental and experimental studies on how children and adult visitors in science museums and planetariums learned about the structure and function of highly spatial scientific objects such as galaxies, supernova, etc. We present a synthesis of the results from these studies and implications for stereoscopic visualization development. The overall finding is that the impact of stereoscopy on perceptions of scientific objects is limited when presented as static imagery. However, when presented as full motion films, a significantly positive impact was detected. To conclude, we present a set of stereoscopic design principles that can help design astronomical stereoscopic films that support deep and effective learning. Our studies cover astronomical content such as the engineering of and imagery from the Mars rovers, artistic stereoscopic imagery of nebulae and a high-resolution stereoscopic film about how astronomers measure and model the structure of our galaxy.

Effectiveness of Immersive Videos in Inducing Awe: An Experimental Study.

PubMed

Chirico, Alice; Cipresso, Pietro; Yaden, David B; Biassoni, Federica; Riva, Giuseppe; Gaggioli, Andrea

2017-04-27

Awe, a complex emotion composed by the appraisal components of vastness and need for accommodation, is a profound and often meaningful experience. Despite its importance, psychologists have only recently begun empirical study of awe. At the experimental level, a main issue concerns how to elicit high intensity awe experiences in the lab. To address this issue, Virtual Reality (VR) has been proposed as a potential solution. Here, we considered the highest realistic form of VR: immersive videos. 42 participants watched at immersive and normal 2D videos displaying an awe or a neutral content. After the experience, they rated their level of awe and sense of presence. Participants' psychophysiological responses (BVP, SC, sEMG) were recorded during the whole video exposure. We hypothesized that the immersive video condition would increase the intensity of awe experienced compared to 2D screen videos. Results indicated that immersive videos significantly enhanced the self-reported intensity of awe as well as the sense of presence. Immersive videos displaying an awe content also led to higher parasympathetic activation. These findings indicate the advantages of using VR in the experimental study of awe, with methodological implications for the study of other emotions.

Federal Ocean Energy Technology

NASA Astrophysics Data System (ADS)

1987-10-01

The Department of Energy's (DOE) Ocean Energy Technology (OET) Program is looking for cost-effective ways to harness ocean energy to help power tomorrow's world. Federally sponsored researchers are studying methods to transform the solar heat stored in the ocean's surface waters into electricity as well as new ways to convert wave energy into mechanical energy or electricity. This report provides a summary of research completed during FY86. Four major research areas are addressed in the work covered by this report: Thermodynamic Research and Analysis addresses the process and system analyses which provide the underlying understanding of physical effects which constitute the energy conversion processes, Experimental Verification and Testing provides confirmation of the analytical projections and empirical relationships, Materials and Structural Research addresses special materials compatibility issues related to operation in the sea. Much of its focus is on concepts for the system CWP which is a major technology cost driver, and Oceanographic, Environmental, and Geotechnical Research addresss those unique design requirements imposed by construction in steep slope coastal areas.

The glass ceiling is not fragile: A response to Odum (2000).

PubMed

McSweeney, F K; Swindell, S

2001-01-01

Odum (2000) criticized our recent conclusions about the participation of women in the experimental analysis of behavior (McSweeney & Swindell, 1998). We address her criticisms here. We argue against the need for statistical tests. We show that our conclusions still apply to all journals except the Journal of the Experimental Analysis of Behavior even when we include the senior editorial staff along with members of the editorial board. We argue that the data that Odum provides to show gender equity are limited, inconsistent with past findings, and hard to interpret in the absence of other data. Finally, we argue that Odum failed to address our most convincing argument for gender inequity and misinterpreted our suggestions for improvements.

Experimental realization of a multiplexed quantum memory with 225 individually accessible memory cells.

PubMed

Pu, Y-F; Jiang, N; Chang, W; Yang, H-X; Li, C; Duan, L-M

2017-05-08

To realize long-distance quantum communication and quantum network, it is required to have multiplexed quantum memory with many memory cells. Each memory cell needs to be individually addressable and independently accessible. Here we report an experiment that realizes a multiplexed DLCZ-type quantum memory with 225 individually accessible memory cells in a macroscopic atomic ensemble. As a key element for quantum repeaters, we demonstrate that entanglement with flying optical qubits can be stored into any neighboring memory cells and read out after a programmable time with high fidelity. Experimental realization of a multiplexed quantum memory with many individually accessible memory cells and programmable control of its addressing and readout makes an important step for its application in quantum information technology.

A survey of urban climate change experiments in 100 cities

PubMed Central

Castán Broto, Vanesa; Bulkeley, Harriet

2013-01-01

Cities are key sites where climate change is being addressed. Previous research has largely overlooked the multiplicity of climate change responses emerging outside formal contexts of decision-making and led by actors other than municipal governments. Moreover, existing research has largely focused on case studies of climate change mitigation in developed economies. The objective of this paper is to uncover the heterogeneous mix of actors, settings, governance arrangements and technologies involved in the governance of climate change in cities in different parts of the world. The paper focuses on urban climate change governance as a process of experimentation. Climate change experiments are presented here as interventions to try out new ideas and methods in the context of future uncertainties. They serve to understand how interventions work in practice, in new contexts where they are thought of as innovative. To study experimentation, the paper presents evidence from the analysis of a database of 627 urban climate change experiments in a sample of 100 global cities. The analysis suggests that, since 2005, experimentation is a feature of urban responses to climate change across different world regions and multiple sectors. Although experimentation does not appear to be related to particular kinds of urban economic and social conditions, some of its core features are visible. For example, experimentation tends to focus on energy. Also, both social and technical forms of experimentation are visible, but technical experimentation is more common in urban infrastructure systems. While municipal governments have a critical role in climate change experimentation, they often act alongside other actors and in a variety of forms of partnership. These findings point at experimentation as a key tool to open up new political spaces for governing climate change in the city. PMID:23805029

Which experimental systems should we use for human microbiome science?

PubMed

Douglas, Angela E

2018-03-01

Microbiome science is revealing that the phenotype and health of animals, including humans, depend on the sustained function of their resident microorganisms. In this essay, I argue for thoughtful choice of model systems for human microbiome science. A greater variety of experimental systems, including wider use of invertebrate models, would benefit biomedical research, while systems ill-suited to experimental and genetic manipulation can be used to address very limited sets of scientific questions. Microbiome science benefits from the coordinated use of multiple systems, which is facilitated by networks of researchers with expertise in different experimental systems.

Non-Equilbrium Fermi Gases

DTIC Science & Technology

2016-02-02

understanding is the experimental verification of a new model of light-induced loss spectra, employing continuum-dressed basis states, which agrees in...and additional qualifiers separated by commas, e.g. Smith, Richard, J, Jr. 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES). Self -explanatory... verification of a new model of light-induced loss spectra, employing continuum-dressed basis states, which agrees in shape and magnitude with all of our

Time Management: Addressing and Assessing Classroom Participation Problems

DTIC Science & Technology

2015-01-01

Time Management Addressing and Assessing Classroom Participation Problems Cary A. Balser Abstract While research shows that technology in...novel experimental design in concert with SmartSync technology to block cadet use of internet and outlook email on their computers in order to measure...undergraduate institution with a clear focus on STEM, technology in the classroom is very nearly necessitated by the content in many technical courses

Research at USAFA 2013

DTIC Science & Technology

2013-01-01

9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) 11 . SPONSOR/MONITOR’S REPORT NUMBER(S) 12. DISTRIBUTION...computer programs, this cadet team is developing this new type of model for a radio controlled aircraft, which will be verified through experimental...complement of researchers available to mentor and lead cadets in their development as engineers and officers,” said McLaughlin . 11 Research at USAFA

How scientific experiments are designed: Problem solving in a knowledge-rich, error-rich environment

NASA Astrophysics Data System (ADS)

Baker, Lisa M.

While theory formation and the relation between theory and data has been investigated in many studies of scientific reasoning, researchers have focused less attention on reasoning about experimental design, even though the experimental design process makes up a large part of real-world scientists' reasoning. The goal of this thesis was to provide a cognitive account of the scientific experimental design process by analyzing experimental design as problem-solving behavior (Newell & Simon, 1972). Three specific issues were addressed: the effect of potential error on experimental design strategies, the role of prior knowledge in experimental design, and the effect of characteristics of the space of alternate hypotheses on alternate hypothesis testing. A two-pronged in vivo/in vitro research methodology was employed, in which transcripts of real-world scientific laboratory meetings were analyzed as well as undergraduate science and non-science majors' design of biology experiments in the psychology laboratory. It was found that scientists use a specific strategy to deal with the possibility of error in experimental findings: they include "known" control conditions in their experimental designs both to determine whether error is occurring and to identify sources of error. The known controls strategy had not been reported in earlier studies with science-like tasks, in which participants' responses to error had consisted of replicating experiments and discounting results. With respect to prior knowledge: scientists and undergraduate students drew on several types of knowledge when designing experiments, including theoretical knowledge, domain-specific knowledge of experimental techniques, and domain-general knowledge of experimental design strategies. Finally, undergraduate science students generated and tested alternates to their favored hypotheses when the space of alternate hypotheses was constrained and searchable. This result may help explain findings of confirmation bias in earlier studies using science-like tasks, in which characteristics of the alternate hypothesis space may have made it unfeasible for participants to generate and test alternate hypotheses. In general, scientists and science undergraduates were found to engage in a systematic experimental design process that responded to salient features of the problem environment, including the constant potential for experimental error, availability of alternate hypotheses, and access to both theoretical knowledge and knowledge of experimental techniques.

Wavelength-addressed intra-board optical interconnection by plug-in alignment with a micro hole array

NASA Astrophysics Data System (ADS)

Nakama, Kenichi; Tokiwa, Yuu; Mikami, Osamu

2010-09-01

Intra-board interconnection between optical waveguide channels is suitable for assembling high-speed optoelectronic printed wiring boards (OE-PWB). Here, we propose a novel optical interconnection method combining techniques for both wavelength-based optical waveguide addressing and plug-in optical waveguide alignment with a micro-hole array (MHA). This array was fabricated by the mask transfer method. For waveguide addressing, we used a micro passive wavelength selector (MPWS) module, which is a type of Littrow mount monochromator consisting of an optical diffraction grating, a focusing lens, and the MHA. From the experimental results, we found that the wavelength addressing operation of the MPWS module was effective for intra-board optical interconnection.

Experimental Design and Primary Data Analysis Methods for Comparing Adaptive Interventions

PubMed Central

Nahum-Shani, Inbal; Qian, Min; Almirall, Daniel; Pelham, William E.; Gnagy, Beth; Fabiano, Greg; Waxmonsky, Jim; Yu, Jihnhee; Murphy, Susan

2013-01-01

In recent years, research in the area of intervention development is shifting from the traditional fixed-intervention approach to adaptive interventions, which allow greater individualization and adaptation of intervention options (i.e., intervention type and/or dosage) over time. Adaptive interventions are operationalized via a sequence of decision rules that specify how intervention options should be adapted to an individual’s characteristics and changing needs, with the general aim to optimize the long-term effectiveness of the intervention. Here, we review adaptive interventions, discussing the potential contribution of this concept to research in the behavioral and social sciences. We then propose the sequential multiple assignment randomized trial (SMART), an experimental design useful for addressing research questions that inform the construction of high-quality adaptive interventions. To clarify the SMART approach and its advantages, we compare SMART with other experimental approaches. We also provide methods for analyzing data from SMART to address primary research questions that inform the construction of a high-quality adaptive intervention. PMID:23025433

Effect of doping on the photocatalytic, electronic and mechanical properties of sol-gel titanium dioxide films

NASA Astrophysics Data System (ADS)

Kurtoglu, Murat

Heterogeneous photocatalysis has been an active research area over the last decade as a promising solution for energy generation and environmental problems which has led to promising applications from air and water purification systems, self-cleaning and self-sterilizing surfaces to solar cells and hydrogen production from water dissociation reaction. Titanium dioxide (TiO2), an abundant material with a high photocatalytic efficiency and chemical stability, is undoubtedly the most widely studied and used among all photocatalytic materials. Although titanium dioxide has been used in powder form, its immobilized form (film) is necessary from practical application standpoint. However, there are several shortcomings of titanium dioxide films that need to be addressed to realize a wide range of successful applications: lack of visible light activity, poisoning of the catalytic performance by the substrate and the low surface area compared to powder forms. In addition, mechanical properties of such films have not been investigated thoroughly, which may be critical when abrasion and weathering resistance are necessary. To address each of these issues, a systematic experimental and theoretical investigation of doping titanium dioxide films with a variety of elements were conducted. Utilizing theoretical calculations to filter elements for experimental studies as well as interpretation of the experimental results, several dopant or dopant combinations were found to remedy some of the issues of photocatalytic titanium dioxide films. Doping with 32 metals, nitrogen and 11 metal-nitrogen combinations are investigated theoretically and the results are used as guideline for the experimental studies. Particular attention is given to certain metal dopants such as Cr, V, Mo, Ta and Ga not just because of their relatively modest cost but also their non-toxicity and wide availability of their compatible compounds for sol-gel synthesis. While metal-dopants improved the overall efficiency and mechanical properties of titanium dioxide films, visible light activity is only achieved with nitrogen and metal-nitrogen doping where some of the metal co-dopants significantly improved the overall photocatalytic efficiency compared to nitrogen-only doped films. In addition, majority of the experimental studies is accompanied by nanoindentation technique to study the effect of doping and calcination on the key mechanical properties of titanium dioxide films. It is shown that good mechanical properties---good photocatalytic activity combinations can be achieved by a choice of appropriate dopant---dopant combinations and coupled with appropriate calcination parameters. Results of the theoretical and experimental investigations led to the development of first commercial photocatalytic tableware glass items which can be utilized under indoor lighting conditions by carefully selecting metal-nitrogen couples for doping of titanium dioxide films.

On the CO2 Wettability of Reservoir Rocks: Addressing Conflicting Information

NASA Astrophysics Data System (ADS)

Garing, C.; Wang, S.; Tokunaga, T. K.; Wan, J.; Benson, S. M.

2017-12-01

Conventional wisdom is that siliclastic rocks are strongly water wet for the CO2-brine system, leading to high irreducible water saturation, moderate residual gas trapping and implying that tight rocks provide efficient seals for buoyant CO2. If the wetting properties become intermediate or CO2 wet, the conclusions regarding CO2 flow and trapping could be very different. Addressing the CO2 wettability of seal and reservoir rocks is therefore essential to predict CO2 storage in geologic formation. Although a substantial amount of work has been dedicated to the topic, contact angle data show a large variability and experiments on plates, micromodels and cores report conflicting results regarding the influence of supercritical CO2 (scCO2) exposure on wetting properties: whereas some experimental studies suggest dewetting upon reaction with scCO2, some others observe no wettability alteration under reservoir scCO2 conditions. After reviewing evidences for and against wettability changes associated with scCO2, we discuss potential causes for differences in experimental results. They include the presence of organic matter and impact of sample treatment, the type of media (non consolidated versus real rock), experimental time and exposure to scCO2, and difference in measurement system (porous plate versus stationary fluid method). In order to address these points, new scCO2/brine drainage-imbibition experiments were conducted on a same Berea sandstone rock core, first untreated, then fired and finally exposed to scCO2 for three weeks, using the stationary fluid method. The results are compared to similar experiments performed on quartz sands, untreated and then baked, using the porous plate method. In addition, a comparative experiment using the same Idaho gray sandstone rock core was performed with both the porous plate and the stationary fluid methods to investigate possible method-dependent results.

Surface physics-materials science research possibilities on a lunar base

NASA Astrophysics Data System (ADS)

Ignatiev, A.

1990-03-01

The benefits of experimental investigations are discussed in terms of the vacuum environment and low-gravity conditions which can be made possible by a lunar base. The proposed experiments address the interaction of UV and cosmic radiation with the atomic surfaces and bulk properties of materials, the study of microclusters, and the development of epitaxial films in a lunar environment. The interaction of low- and high-energy charged particles and radiation with materials can potentially be studied to analyze the use of the materials in space.

Models in the Design and Validation of Eddy Current Inspection for Cracking in the Shuttle Reaction Control System Thruster

NASA Technical Reports Server (NTRS)

Aldrin, John C.; Williams, Phillip A.; Wincheski, Russell (Buzz) A.

2008-01-01

A case study is presented for using models in eddy current NDE design for crack detection in Shuttle Reaction Control System thruster components. Numerical methods were used to address the complex geometry of the part and perform parametric studies of potential transducer designs. Simulations were found to show agreement with experimental results. Accurate representation of the coherent noise associated with the measurement and part geometry was found to be critical to properly evaluate the best probe designs.

Towards Polarised Antiprotons: Machine Developments for Spin-Filtering Studies

NASA Astrophysics Data System (ADS)

Lenisa, Paolo

2016-02-01

We address the commissioning of the experimental equipment and the machine studies required for the first spin-filtering experiment with protons at the COSY ring in Jülich (Germany) at a beam kinetic energy of 49.3 MeV. The implementation of a low-beta insertion made it possible to achieve beam lifetimes of 8000 s in the presence of a dense polarized hydrogen storage cell target. The developed techniques can be directly applied to antiproton machines and allow for the determination of the spin-dependent pbar-p cross sections via spin-filtering.

Theories and models on the biological of cells in space

NASA Technical Reports Server (NTRS)

Todd, P.; Klaus, D. M.

1996-01-01

A wide variety of observations on cells in space, admittedly made under constraining and unnatural conditions in may cases, have led to experimental results that were surprising or unexpected. Reproducibility, freedom from artifacts, and plausibility must be considered in all cases, even when results are not surprising. The papers in symposium on 'Theories and Models on the Biology of Cells in Space' are dedicated to the subject of the plausibility of cellular responses to gravity -- inertial accelerations between 0 and 9.8 m/sq s and higher. The mechanical phenomena inside the cell, the gravitactic locomotion of single eukaryotic and prokaryotic cells, and the effects of inertial unloading on cellular physiology are addressed in theoretical and experimental studies.

Experimental study of planetary gases with applications to planetary interior models

NASA Technical Reports Server (NTRS)

Bell, Peter M.; Mao, Ho-Kwang

1988-01-01

High-pressure experimental data on planetary materials are critical in developing planetary models and in addressing otherwise insoluble problems of the internal structure of the major planets. Progress in the last five years has been particularly marked. Maximum static pressure of 550 GPa was achieved. For the first time, X-ray diffraction of solidified gases (Ne, Xe) and ices (H2O) were obtained at pressures above one megabar, single-crystal diffraction of ultralight elements (H2, He) were detected up to 25 GPa, pressures over 200 GPa at 77 K were reached in solid hydrogen, including the discovery of a phase transformation in the molecular solid. Advances in instrumentation and new measurements performed during 1983 to 1988 are summarized.

Nanotechnology in Li-ion Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mukaibo, Hitomi

2010-06-04

This is the second of three talks on nanostructures for li-ion batteries. The talks provide an up-to-date review of the issues and challenges facing Li-ion battery research with special focus on how nanostructures/ nanotechnology are being applied to this field. Novel materials reported as prospective candidates for anode, cathode and electrolyte will be summarized. The expected role of nanostructures in improving the performance of Li-ion batteries and the actual pros and cons of using such structures in this device will be addressed. Electrochemical experiments used to study Li-ion batteries will also be discussed. This includes the introduction to the standardmore » experimental set-up and how experimental data (from charge-discharge experiments, cyclic voltammetry, impedance spectroscopy, etc) are interpreted.« less

Towards a Deeper Understanding of the Nucleus with Exotic Nuclei

NASA Astrophysics Data System (ADS)

Ormand, Erich

2006-10-01

Despite more than fifty years of study, many questions about now nuclei are put together remain. While nuclei near the valley of stability have provided a wealth of information, they are not sufficient to provide us with a comprehensive and unified description of the nucleus. Especially lacking is an accurate picture of those exotic species that are the basis of cosmic alchemy. The missing pieces in the puzzle can be filled in with a determined experimental and theoretical effort focusing on nuclei lying far from the valley of stability. Here, I will outline the intellectual challenges that can be addressed by proposed exotic-beam facilities, and how new experimental data will quide and refine theoretical descriptions of the nucleus.

Impact of ablator thickness and laser drive duration on a platform for supersonic, shockwave-driven hydrodynamic instability experiments

DOE PAGES

Wan, W. C.; Malamud, Guy; Shimony, A.; ...

2016-12-07

Here, we discuss changes to a target design that improved the quality and consistency of data obtained through a novel experimental platform that enables the study of hydrodynamic instabilities in a compressible regime. The experiment uses a laser to drive steady, supersonic shockwave over well-characterized initial perturbations. Early experiments were adversely affected by inadequate experimental timescales and, potentially, an unintended secondary shockwave. These issues were addressed by extending the 4 x 10 13 W/cm 2 laser pulse from 19 ns to 28 ns, and increasing the ablator thickness from 185 µm to 500 µm. We present data demonstrating the performancemore » of the platform.« less

The paradox of cognitive flexibility in autism

PubMed Central

Geurts, Hilde M.; Corbett, Blythe; Solomon, Marjorie

2017-01-01

We present an overview of current literature addressing cognitive flexibility in autism spectrum disorders. Based on recent studies at multiple sites, using diverse methods and participants of different autism subtypes, ages and cognitive levels, no consistent evidence for cognitive flexibility deficits was found. Researchers and clinicians assume that inflexible everyday behaviors in autism are directly related to cognitive flexibility deficits as assessed by clinical and experimental measures. However, there is a large gap between the day-to-day behavioral flexibility and that measured with these cognitive flexibility tasks. To advance the field, experimental measures must evolve to reflect mechanistic models of flexibility deficits. Moreover, ecologically valid measures are required to be able to resolve the paradox between cognitive and behavioral inflexibility. PMID:19138551

Impact of ablator thickness and laser drive duration on a platform for supersonic, shockwave-driven hydrodynamic instability experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wan, W. C.; Malamud, Guy; Shimony, A.

Here, we discuss changes to a target design that improved the quality and consistency of data obtained through a novel experimental platform that enables the study of hydrodynamic instabilities in a compressible regime. The experiment uses a laser to drive steady, supersonic shockwave over well-characterized initial perturbations. Early experiments were adversely affected by inadequate experimental timescales and, potentially, an unintended secondary shockwave. These issues were addressed by extending the 4 x 10 13 W/cm 2 laser pulse from 19 ns to 28 ns, and increasing the ablator thickness from 185 µm to 500 µm. We present data demonstrating the performancemore » of the platform.« less

Status and trends monitoring of riparian and aquatic habitat in the Olympic Experimental State Forest: Monitoring protocols

Treesearch

Teodora Minkova; Alex D. Foster

2017-01-01

Presented here are the monitoring protocols for the Status and Trends Monitoring of Riparian and Aquatic Habitats project in the Olympic Experimental State Forest (OESF). The procedures yield the empirical data needed to address key uncertainties regarding the integration of timber production and habitat conservation across landscapes and assess progress toward...

An application of artificial neural networks to experimental data approximation

NASA Technical Reports Server (NTRS)

Meade, Andrew J., Jr.

1993-01-01

As an initial step in the evaluation of networks, a feedforward architecture is trained to approximate experimental data by the backpropagation algorithm. Several drawbacks were detected and an alternative learning algorithm was then developed to partially address the drawbacks. This noniterative algorithm has a number of advantages over the backpropagation method and is easily implemented on existing hardware.

Experimental Neutrino Physics

ScienceCinema

Walter, Chris

2018-01-12

In this talk, I will review how a set of experiments in the last decade has given us our current understanding of neutrino properties.  I will show how experiments in the last year or two have clarified this picture, and will discuss how new experiments about to start will address remaining questions.  I will particularly emphasize the relationship between various experimental techniques.

The Dynamics of Miscible Interfaces: Simulations

NASA Technical Reports Server (NTRS)

Meiburg, Eckart

2002-01-01

The goal of this experimental/computational investigation (joint with Prof Maxworthy at USC) has been to study the dynamics of miscible interfaces, both from a scientific and a practical point of view, and to prepare a related experiment to be flown on the International Space Station. In order to address these effects, we have focused experimental and computational investigations on miscible displacements in cylindrical capillary tubes, as well as in Hele-Shaw cells. Regarding the flow in a capillary tube, the question was addressed as to whether Korteweg stresses and/or divergence effects can potentially account for discrepancies observed between conventional Stokes flow simulations and experiments for miscible flows in capillary tubes. An estimate of the vorticity and streamfunction fields induced by the Kortewegs stresses was derived, which shows these stresses to result in the formation of a vortex ring structure near the tip of the concentration front. Through this mechanism the propagation velocity of the concentration front is reduced, in agreement with the experimental observations. Divergence effects, on the other hand, were seen to be very small, and they have a negligible influence on the tip velocity. As a result, it can be concluded that they are not responsible for the discrepancies between experiments and conventional Stokes simulations. A further part of our investigation focussed on the development of high-accuracy three-dimensional spectral element simulation techniques for miscible flows in capillary tubes, including the effects of variable density and viscosity. Towards this end, the conservation equations are treated in cylindrical coordinates.

Weighing up the evidence: a systematic review of the effectiveness of workplace interventions to tackle socio-economic inequalities in obesity

PubMed Central

Cairns, Joanne-Marie; Bambra, Clare; Hillier-Brown, Frances C.; Moore, Helen J.; Summerbell, Carolyn D.

2015-01-01

Abstract Background Addressing socio-economic inequalities in obesity is a public health priority and the workplace is seen as a potential health promotion site. However, there is a lack of evidence on what works. This article systematically reviews studies of the effects of workplace interventions on socio-economic inequalities in obesity. Methods Following PRISMA guidelines, we searched for published or unpublished experimental and observational evaluation studies. Nine electronic databases were searched as well as websites and bibliographies. Included studies were data extracted, quality assessed and narratively synthesized. Results Eighteen studies were included of which 14 examined behavioural interventions and 4 mixed or environmental ones. While most studies (n = 12) found no effects on inequalities in obesity—and a minority found increases (n = 3), there was also some evidence of potentially effective workplace interventions (n = 3) especially in terms of physical activity interventions targeted at lower occupational groups. Conclusion There is experimental evidence that workplace delivered physical activity interventions have the potential to reduce inequalities in obesity by targeting lower occupational groups. However, overall, the evidence base is small, largely from the USA, and of a low quality. More high-quality, experimental study designs are required. PMID:25316262

Quality and safety in the transitional care of the elderly (phase 2): the study protocol of a quasi-experimental intervention study for a cross-level educational programme

PubMed Central

Storm, Marianne; Groene, Oliver; Testad, Ingelin; Dyrstad, Dagrunn N; Heskestad, Randi N; Aase, Karina

2014-01-01

Introduction Transitional care and patient handover are important areas to ensure quality and safety in elderly healthcare services. Previous studies showed that healthcare professionals have little knowledge of the setting they are transferring patients to and a limited understanding of roles and functions; these constitute barriers to effective communication and shared care responsibilities across levels of care. Aim The main objective is to implement a cross-level education-based intervention programme with healthcare professionals aimed at (1) increasing professionals’ awareness and competencies about quality and safety in the transitional care of the elderly; (2) creating a discussion platform for knowledge exchange and learning across levels and units of care and (3) improving patient safety culture, in particular, in transitional care. Methods and analysis A quasi-experimental control group study design with an intervention group and a control group; this includes a pretest, post-test and 1-year follow-up test assessment of patient safety culture. Qualitative data will be collected during the intervention programme and between the measurements. The study design will be beneficial for addressing the effects of the cross-level educational intervention programme on reports of patient safety culture and for addressing the feasibility of the intervention measures. Ethics and dissemination The study has been approved by the Regional Committees for Medical and Health Research Ethics in Norway, Ref. No. 2011/1978. The study is based on informed written consent; informants can withdraw from the study at any point in time. The results will be disseminated at research conferences, in peer review journals and through public presentations outside the scientific community. PMID:25082425

Recommendations for research design of telehealth studies.

PubMed

Chumbler, Neale R; Kobb, Rita; Brennan, David M; Rabinowitz, Terry

2008-11-01

Properly designed randomized controlled trials (RCTs) are the gold standard to use when examining the effectiveness of telehealth interventions on clinical outcomes. Some published telehealth studies have employed well-designed RCTs. However, such methods are not always feasible and practical in particular settings. This white paper addresses not only the need for properly designed RCTs, but also offers alternative research designs, such as quasi-experimental designs, and statistical techniques that can be employed to rigorously assess the effectiveness of telehealth studies. This paper further offers design and measurement recommendations aimed at and relevant to administrative decision-makers, policymakers, and practicing clinicians.

The Role of Psychometrics in Individual Differences Research in Cognition: A Case Study of the AX-CPT

PubMed Central

Cooper, Shelly R.; Gonthier, Corentin; Barch, Deanna M.; Braver, Todd S.

2017-01-01

Investigating individual differences in cognition requires addressing questions not often thought about in standard experimental designs, especially regarding the psychometric properties of the task. Using the AX-CPT cognitive control task as a case study example, we address four concerns that one may encounter when researching the topic of individual differences in cognition. First, we demonstrate the importance of variability in task scores, which in turn directly impacts reliability, particularly when comparing correlations in different populations. Second, we demonstrate the importance of variability and reliability for evaluating potential failures to replicate predicted correlations, even within the same population. Third, we demonstrate how researchers can turn to evaluating psychometric properties as a way of evaluating the feasibility of utilizing the task in new settings (e.g., online administration). Lastly, we show how the examination of psychometric properties can help researchers make informed decisions when designing a study, such as determining the appropriate number of trials for a task. PMID:28928690

Multilevel Methodology for Simulation of Spatio-Temporal Systems with Heterogeneous Activity; Application to Spread of Valley Fever Fungus

USGS Publications Warehouse

Jammalamadaka, Rajanikanth

2009-01-01

This report consists of a dissertation submitted to the faculty of the Department of Electrical and Computer Engineering, in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Graduate College, The University of Arizona, 2008. Spatio-temporal systems with heterogeneity in their structure and behavior have two major problems associated with them. The first one is that such complex real world systems extend over very large spatial and temporal domains and consume so many computational resources to simulate that they are infeasible to study with current computational platforms. The second one is that the data available for understanding such systems is limited because they are spread over space and time making it hard to obtain micro and macro measurements. This also makes it difficult to get the data for validation of their constituent processes while simultaneously considering their global behavior. For example, the valley fever fungus considered in this dissertation is spread over a large spatial grid in the arid Southwest and typically needs to be simulated over several decades of time to obtain useful information. It is also hard to get the temperature and moisture data (which are two critical factors on which the survival of the valley fever fungus depends) at every grid point of the spatial domain over the region of study. In order to address the first problem, we develop a method based on the discrete event system specification which exploits the heterogeneity in the activity of the spatio-temporal system and which has been shown to be effective in solving relatively simple partial differential equation systems. The benefit of addressing the first problem is that it now makes it feasible to address the second problem. We address the second problem by making use of a multilevel methodology based on modeling and simulation and systems theory. This methodology helps us in the construction of models with different resolutions (base and lumped models). This allows us to refine an initially constructed lumped model with detailed physics-based process models and assess whether they improve on the original lumped models. For that assessment, we use the concept of experimental frame to delimit where the improvement is needed. This allows us to work with the available data, improve the component models in their own experimental frame and then move them to the overall frame. In this dissertation, we develop a multilevel methodology and apply it to a valley fever model. Moreover, we study the model's behavior in a particular experimental frame of interest, namely the formation of new sporing sites.

Experimental liver fibrosis research: update on animal models, legal issues and translational aspects

PubMed Central

2013-01-01

Liver fibrosis is defined as excessive extracellular matrix deposition and is based on complex interactions between matrix-producing hepatic stellate cells and an abundance of liver-resident and infiltrating cells. Investigation of these processes requires in vitro and in vivo experimental work in animals. However, the use of animals in translational research will be increasingly challenged, at least in countries of the European Union, because of the adoption of new animal welfare rules in 2013. These rules will create an urgent need for optimized standard operating procedures regarding animal experimentation and improved international communication in the liver fibrosis community. This review gives an update on current animal models, techniques and underlying pathomechanisms with the aim of fostering a critical discussion of the limitations and potential of up-to-date animal experimentation. We discuss potential complications in experimental liver fibrosis and provide examples of how the findings of studies in which these models are used can be translated to human disease and therapy. In this review, we want to motivate the international community to design more standardized animal models which might help to address the legally requested replacement, refinement and reduction of animals in fibrosis research. PMID:24274743

Controlling and culturing diversity: experimental zoology before World War II and Vienna's Biologische Versuchsanstalt.

PubMed

Logan, Cheryl A; Brauckmann, Sabine

2015-04-01

Founded in Vienna in 1903, the Institute for Experimental Biology pioneered the application of experimental methods to living organisms maintained for sustained periods in captivity. Its Director, the zoologist Hans Przibram, oversaw until 1938, the attempt to integrate ontogeny with studies of inheritance using precise and controlled measurements of the impact of environmental influences on the emergence of form and function. In the early years, these efforts paralleled and even fostered the emergence of experimental biology in America. But fate intervened. Though the Institute served an international community, most of its resident scientists and staff were of Jewish ancestry. Well before the Nazis entered Austria in 1938, these men and women were being fired and driven out; some, including Przibram, were eventually killed. We describe the unprecedented facilities built and the topics addressed by the several departments that made up this Institute, stressing those most relevant to the establishment and success of the Journal of Experimental Zoology, which was founded just a year later. The Institute's diaspora left an important legacy in North America, perhaps best embodied by the career of the developmental neuroscientist Paul Weiss. © 2015 Wiley Periodicals, Inc.

A Diverse Community To Study Communities: Integration of Experiments and Mathematical Models To Study Microbial Consortia.

PubMed

Succurro, Antonella; Moejes, Fiona Wanjiku; Ebenhöh, Oliver

2017-08-01

The last few years have seen the advancement of high-throughput experimental techniques that have produced an extraordinary amount of data. Bioinformatics and statistical analyses have become instrumental to interpreting the information coming from, e.g., sequencing data and often motivate further targeted experiments. The broad discipline of "computational biology" extends far beyond the well-established field of bioinformatics, but it is our impression that more theoretical methods such as the use of mathematical models are not yet as well integrated into the research studying microbial interactions. The empirical complexity of microbial communities presents challenges that are difficult to address with in vivo / in vitro approaches alone, and with microbiology developing from a qualitative to a quantitative science, we see stronger opportunities arising for interdisciplinary projects integrating theoretical approaches with experiments. Indeed, the addition of in silico experiments, i.e., computational simulations, has a discovery potential that is, unfortunately, still largely underutilized and unrecognized by the scientific community. This minireview provides an overview of mathematical models of natural ecosystems and emphasizes that one critical point in the development of a theoretical description of a microbial community is the choice of problem scale. Since this choice is mostly dictated by the biological question to be addressed, in order to employ theoretical models fully and successfully it is vital to implement an interdisciplinary view at the conceptual stages of the experimental design. Copyright © 2017 Succurro et al.

A model of human event detection in multiple process monitoring situations

NASA Technical Reports Server (NTRS)

Greenstein, J. S.; Rouse, W. B.

1978-01-01

It is proposed that human decision making in many multi-task situations might be modeled in terms of the manner in which the human detects events related to his tasks and the manner in which he allocates his attention among his tasks once he feels events have occurred. A model of human event detection performance in such a situation is presented. An assumption of the model is that, in attempting to detect events, the human generates the probability that events have occurred. Discriminant analysis is used to model the human's generation of these probabilities. An experimental study of human event detection performance in a multiple process monitoring situation is described and the application of the event detection model to this situation is addressed. The experimental study employed a situation in which subjects simulataneously monitored several dynamic processes for the occurrence of events and made yes/no decisions on the presence of events in each process. Input to the event detection model of the information displayed to the experimental subjects allows comparison of the model's performance with the performance of the subjects.

Chaotic Dynamics and Application of LCR Oscillators Sharing Common Nonlinearity

NASA Astrophysics Data System (ADS)

Jeevarekha, A.; Paul Asir, M.; Philominathan, P.

2016-06-01

This paper addresses the problem of sharing common nonlinearity among nonautonomous and autonomous oscillators. By choosing a suitable common nonlinear element with the driving point characteristics capable of bringing out chaotic motion in a combined system, we obtain identical chaotic states. The dynamics of the coupled system is explored through numerical and experimental studies. Employing the concept of common nonlinearity, a simple chaotic communication system is modeled and its performance is verified through Multisim simulation.

Charge transport with single molecules--an electrochemical approach.

PubMed

Li, Chen; Mishchenko, Artem; Pobelov, Ilya; Wandlowski, Thomas

2010-01-01

After an introduction and brief review of charge transport in nanoscale molecular systems we report on experimental studies in gold / (single) molecule / gold junctions at solid / liquid interfaces employing a scanning tunneling microscopy (STM)-based 'break junction' technique. We demonstrate attempts in developing basic relationships between molecular structure, conductance properties and nanoscale electrochemical concepts based on four case studies from our own work. In experiments with alpha, omega-alkanedithiol and biphenyldithiol molecular junctions we address the role of sulfur-gold couplings and molecular conformation, such as gauche defects in the alkyl chains and the torsion angle between two phenyl rings. Combination with quantum chemistry calculations enabled a detailed molecular-level understanding of the electronic structure and transport characteristics of both systems. Employing the concept of 'electrolyte gating' with redox-active molecules, such as thiol-terminated derivatives of viologens (HS-6V6-SH or (HS-6V6)) we demonstrate the construction of symmetric and asymmetric active molecular junctions with transistor- or diode-like behavior upon polarization in an electrochemical environment. The experimental data could be represented quantitatively by the Kutznetsov/Ulstrup model assuming a two-step electron transfer with partial vibration relaxation. Finally, we show that surface-immobilized gold nanoparticles with a diameter of (2.4 +/- 0.5) nm exhibit features of locally addressable multi-state electronic switching upon electrolyte gating, which appears to be reminiscent of a sequential charging through several 'oxidation/reduction states'.

Rodent Models of Invasive Aspergillosis due to Aspergillus fumigatus: Still a Long Path toward Standardization

PubMed Central

Desoubeaux, Guillaume; Cray, Carolyn

2017-01-01

Invasive aspergillosis has been studied in laboratory by the means of plethora of distinct animal models. They were developed to address pathophysiology, therapy, diagnosis, or miscellaneous other concerns associated. However, there are great discrepancies regarding all the experimental variables of animal models, and a thorough focus on them is needed. This systematic review completed a comprehensive bibliographic analysis specifically-based on the technical features of rodent models infected with Aspergillus fumigatus. Out the 800 articles reviewed, it was shown that mice remained the preferred model (85.8% of the referenced reports), above rats (10.8%), and guinea pigs (3.8%). Three quarters of the models involved immunocompromised status, mainly by steroids (44.4%) and/or alkylating drugs (42.9%), but only 27.7% were reported to receive antibiotic prophylaxis to prevent from bacterial infection. Injection of spores (30.0%) and inhalation/deposition into respiratory airways (66.9%) were the most used routes for experimental inoculation. Overall, more than 230 distinct A. fumigatus strains were used in models. Of all the published studies, 18.4% did not mention usage of any diagnostic tool, like histopathology or mycological culture, to control correct implementation of the disease and to measure outcome. In light of these findings, a consensus discussion should be engaged to establish a minimum standardization, although this may not be consistently suitable for addressing all the specific aspects of invasive aspergillosis. PMID:28559881

Developmental Origins of Adult Diseases and Neurotoxicity: Epidemiological and Experimental Studies

PubMed Central

Fox, Donald A.; Grandjean, Philippe; de Groot, Didima; Paule, Merle

2013-01-01

To date, only a small number of commercial chemicals have been tested and documented as developmental neurotoxicants. Moreover, an increasing number of epidemiological, clinical and experimental studies suggest an association between toxicant or drug exposure during the perinatal period and the development of metabolic-related diseases and neurotoxicity later in life. The four speakers in this symposium presented their research results on different neurotoxic chemicals as they relate to the developmental origins of health and adult disease (DOHaD). Philippe Grandjean presented epidemiological data on children exposed to methylmercury and discussed the behavioral outcome measures as they relate to age and stage of brain development. Donald A. Fox presented data that low-to-moderate dose human equivalent gestational lead exposure produced late-onset obesity, and motor and coordination dysfunction only in male mice. Didima de Groot discussed the role of caloric restriction and/or high fat diets during gestation and/or postnatal development in mediating the metabolic and neurotoxic effects of developmental methylmercury exposure in rats. Merle G. Paule addressed the long-term changes in learning, motivation and short-term memory in aged Rhesus monkeys following 24 hour exposure to ketamine during early development. Overall, these presentations addressed fundamental issues in the emerging areas of lifetime neurotoxicity testing, differential vulnerable periods of exposure, nonmonotonic dose-response effects and neurotoxic risk assessment. PMID:22245043

The effects of incubation temperature and experimental design on heart rates of lizard embryos.

PubMed

Hulbert, Austin C; Mitchell, Timothy S; Hall, Joshua M; Guiffre, Cassia M; Douglas, Danielle C; Warner, Daniel A

2017-08-01

Many studies of phenotypic plasticity alter environmental conditions during embryonic development, yet only measure phenotypes at the neonatal stage (after embryonic development). However, measuring aspects of embryo physiology enhances our understanding of how environmental factors immediately affect embryos, which aids our understanding of developmental plasticity. While current research on reptile developmental plasticity has demonstrated that fluctuating incubation temperatures affect development differently than constant temperatures, most research on embryo physiology is still performed with constant temperature experiments. In this study, we noninvasively measured embryonic heart rates of the brown anole (Anolis sagrei), across ecologically relevant fluctuating temperatures. We incubated eggs under temperatures measured from potential nests in the field and examined how heart rates change through a diel cycle and throughout embryonic development. We also evaluated how experimental design (e.g., repeated vs. single measures designs, constant vs. fluctuating temperatures) and different protocols (e.g., removing eggs from incubators) might influence heart rate. We found that heart rates were correlated with daily temperature and increased through development. Our findings suggest that experimenters have reasonable flexibility in choosing an experimental design to address their questions; however, some aspects of design and protocol can potentially influence estimations of heart rates. Overall, we present the first ecologically relevant measures of anole embryonic heart rates and provide recommendations for experimental designs for future experiments. © 2017 Wiley Periodicals, Inc.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Labby, Z.

Physicists are often expected to have a solid grounding in experimental design and statistical analysis, sometimes filling in when biostatisticians or other experts are not available for consultation. Unfortunately, graduate education on these topics is seldom emphasized and few opportunities for continuing education exist. Clinical physicists incorporate new technology and methods into their practice based on published literature. A poor understanding of experimental design and analysis could Result in inappropriate use of new techniques. Clinical physicists also improve current practice through quality initiatives that require sound experimental design and analysis. Academic physicists with a poor understanding of design and analysismore » may produce ambiguous (or misleading) results. This can Result in unnecessary rewrites, publication rejection, and experimental redesign (wasting time, money, and effort). This symposium will provide a practical review of error and uncertainty, common study designs, and statistical tests. Instruction will primarily focus on practical implementation through examples and answer questions such as: where would you typically apply the test/design and where is the test/design typically misapplied (i.e., common pitfalls)? An analysis of error and uncertainty will also be explored using biological studies and associated modeling as a specific use case. Learning Objectives: Understand common experimental testing and clinical trial designs, what questions they can answer, and how to interpret the results Determine where specific statistical tests are appropriate and identify common pitfalls Understand the how uncertainty and error are addressed in biological testing and associated biological modeling.« less

Medical experiments on persons with special needs, a comparative study of Islamic jurisprudence vs. Arab laws: UAE law as case study.

PubMed

Hammad, Hamza Abed Al-Karim

2014-01-01

This article is a comparative study of medical experiments on persons with special needs in Islamic jurisprudence and Arab laws; United Arab Emirates (UAE) law as case study. The current study adopts a comparative analytical and descriptive approach. The conclusion of this study points out that the Convention on the Rights of Persons with Special Needs, ratified by a number of Arab States, including the United Arab Emirates, approves conducting medical experiments on persons with special needs, subject to their free consent. As a result of ratifying this Convention, a number of special laws were enacted to be enforced in the United Arab Emirates. On the other hand, this issue is controversial from an Islamic jurisprudence point of view. One group of jurisprudents permits conducting these experimentations if they are designed to treat the person involved, and prohibits such experimentations for scientific advancement. Other jurisprudents permit conducting medical experimentations on persons with special needs, whether the purpose of such experimentations is treatment of the disabled or achieving scientific advancement. The opinion of this group is consistent with the International Convention and the Arab laws in this respect. However, neither the Convention nor the Arab laws regulate this matter by specific and comprehensive conditions, as addressed by some contemporary scholars. It is recommended that the Convention and the Arab laws adopt these conditions. Additionally, the Convention does not state whether the experimentations may be conducted for the interest of the person with disability or for the purpose of scientific advancement. The text of the Convention is unclear and therefore requires further illumination.

Influence of Cultural, Organizational, and Automation Capability on Human Automation Trust: A Case Study of Auto-GCAS Experimental Test Pilots

NASA Technical Reports Server (NTRS)

Koltai, Kolina; Ho, Nhut; Masequesmay, Gina; Niedober, David; Skoog, Mark; Cacanindin, Artemio; Johnson, Walter; Lyons, Joseph

2014-01-01

This paper discusses a case study that examined the influence of cultural, organizational and automation capability upon human trust in, and reliance on, automation. In particular, this paper focuses on the design and application of an extended case study methodology, and on the foundational lessons revealed by it. Experimental test pilots involved in the research and development of the US Air Force's newly developed Automatic Ground Collision Avoidance System served as the context for this examination. An eclectic, multi-pronged approach was designed to conduct this case study, and proved effective in addressing the challenges associated with the case's politically sensitive and military environment. Key results indicate that the system design was in alignment with pilot culture and organizational mission, indicating the potential for appropriate trust development in operational pilots. These include the low-vulnerability/ high risk nature of the pilot profession, automation transparency and suspicion, system reputation, and the setup of and communications among organizations involved in the system development.

Magnetic particle-mediated magnetoreception

PubMed Central

Shaw, Jeremy; Boyd, Alastair; House, Michael; Woodward, Robert; Mathes, Falko; Cowin, Gary; Saunders, Martin; Baer, Boris

2015-01-01

Behavioural studies underpin the weight of experimental evidence for the existence of a magnetic sense in animals. In contrast, studies aimed at understanding the mechanistic basis of magnetoreception by determining the anatomical location, structure and function of sensory cells have been inconclusive. In this review, studies attempting to demonstrate the existence of a magnetoreceptor based on the principles of the magnetite hypothesis are examined. Specific attention is given to the range of techniques, and main animal model systems that have been used in the search for magnetite particulates. Anatomical location/cell rarity and composition are identified as two key obstacles that must be addressed in order to make progress in locating and characterizing a magnetite-based magnetoreceptor cell. Avenues for further study are suggested, including the need for novel experimental, correlative, multimodal and multidisciplinary approaches. The aim of this review is to inspire new efforts towards understanding the cellular basis of magnetoreception in animals, which will in turn inform a new era of behavioural research based on first principles. PMID:26333810

A Guide for the Design of Pre-clinical Studies on Sex Differences in Metabolism.

PubMed

Mauvais-Jarvis, Franck; Arnold, Arthur P; Reue, Karen

2017-06-06

In animal models, the physiological systems involved in metabolic homeostasis exhibit a sex difference. Investigators often use male rodents because they show metabolic disease better than females. Thus, females are not used precisely because of an acknowledged sex difference that represents an opportunity to understand novel factors reducing metabolic disease more in one sex than the other. The National Institutes of Health (NIH) mandate to consider sex as a biological variable in preclinical research places new demands on investigators and peer reviewers who often lack expertise in model systems and experimental paradigms used in the study of sex differences. This Perspective discusses experimental design and interpretation in studies addressing the mechanisms of sex differences in metabolic homeostasis and disease, using animal models and cells. We also highlight current limitations in research tools and attitudes that threaten to delay progress in studies of sex differences in basic animal research. Copyright © 2017 Elsevier Inc. All rights reserved.

The effect of meditation on physical and mental health in junior college students: a quasi-experimental study.

PubMed

Yang, Ke-Ping; Su, Whei-Ming; Huang, Chen-Kuan

2009-12-01

Physical stress and mental stress are increasingly common phenomena in our rapidly changing and stressful modern society. Research has found meditation to produce positive and demonstrable stress reduction effects on brain and immune functions. This study is grounded in traditional Chinese philosophical mores that teach a process summarized by the keynote activities of "calm, still, quiet, consider, and get" and the potential of this process to reduce stress in adolescents. The purpose of this study was to examine the effects of meditation on the physical and mental health of junior college students. This research employed a quasi-experimental design. Participants included 242 freshmen from a junior college in Taiwan selected using a convenience sampling technique. Participants were then randomly separated into experimental (n = 119) and control (n = 123) groups. The project duration was 18 weeks, during which the experimental group received 2 hours of meditation treatment per week, for a total of 36 hours. Both groups completed pretest and posttest Life Adaptation Scale forms, which included questionnaires addressing information on physical and mental distress and positive and negative coping strategies. Data were analyzed using analysis of covariance. Findings showed that the effect of the experiment treatment was significant when student physical and mental distress pretest scores were controlled. Physical and mental symptoms in the experimental group were lower than those in the control group. Meditation can help students to adapt to life stressors. This study also provides support for traditional Chinese wisdom, which promotes meditation as one way to improve health.

A Quantitative Review of Ethnic Group Differences in Experimental Pain Response: Do Biology, Psychology and Culture Matter?

PubMed Central

Riley, Joseph L.; Williams, Ameenah K.K.; Fillingim, Roger B.

2012-01-01

Objective Pain is a subjectively complex and universal experience. We examine research investigating ethnic group differences in experimental pain response, and factors contributing to group differences. Method We conducted a systematic literature review and analysis of studies using experimental pain stimuli to assess pain sensitivity across multiple ethnic groups. Our search covered the period from 1944-2011, and utilized the PUBMED bibliographic database; a reference source containing over 17 million citations. We calculated effect sizes, identified ethnic/racial group categories, pain stimuli and measures, and examined findings regarding biopsychosociocultural factors contributing to ethnic/racial group differences. Results We found 472 studies investigating ethnic group differences and pain. Twenty-six of these met our review inclusion criteria of investigating ethnic group differences in experimental pain. The majority of studies included comparisons between African Americans (AA) and non-Hispanic Whites (NHW). There were consistently moderate to large effect sizes for pain tolerance across multiple stimulus modalities; African Americans demonstrated lower pain tolerance. For pain threshold, findings were generally in the same direction, but effect sizes were small to moderate across ethnic groups. Limited data were available for suprathreshold pain ratings. A subset of studies comparing NHW and other ethnic groups showed a variable range of effect sizes for pain threshold and tolerance. Conclusion There are potentially important ethnic/racial group differences in experimental pain perception. Elucidating ethnic group differences, has translational merit for culturally-competent clinical care and for addressing and reducing pain treatment disparities among ethnically/racially diverse groups. PMID:22390201

A quantitative review of ethnic group differences in experimental pain response: do biology, psychology, and culture matter?

PubMed

Rahim-Williams, Bridgett; Riley, Joseph L; Williams, Ameenah K K; Fillingim, Roger B

2012-04-01

Pain is a subjectively complex and universal experience. We examine research investigating ethnic group differences in experimental pain response and factors contributing to group differences. We conducted a systematic literature review and analysis of studies using experimental pain stimuli to assess pain sensitivity across multiple ethnic groups. Our search covered the period from 1944 to 2011, and used the PubMed bibliographic database; a reference source containing over 17 million citations. We calculated effect sizes; identified ethnic/racial group categories, pain stimuli, and measures; and examined findings regarding biopsychosociocultural factors contributing to ethnic/racial group differences. We found 472 studies investigating ethnic group differences and pain. Twenty-six of these met our review inclusion criteria of investigating ethnic group differences in experimental pain. The majority of studies included comparisons between African Americans (AA) and non-Hispanic Whites (NHW). There were consistently moderate to large effect sizes for pain tolerance across multiple stimulus modalities; AA demonstrated lower pain tolerance. For pain threshold, findings were generally in the same direction, but effect sizes were small to moderate across ethnic groups. Limited data were available for suprathreshold pain ratings. A subset of studies comparing NHW and other ethnic groups showed a variable range of effect sizes for pain threshold and tolerance. There are potentially important ethnic/racial group differences in experimental pain perception. Elucidating ethnic group differences has translational merit for culturally competent clinical care and for addressing and reducing pain treatment disparities among ethnically/racially diverse groups. Wiley Periodicals, Inc.

Trial Support and Data Analysis for 2015 ONR Sea-Trial

DTIC Science & Technology

2017-06-21

Report Chad M. Smith The Pennsylvania State University Applied Research Laboratory P.O. Box 30 State College, PA 16804-0030 phone: (814) 863...was the support of the PI and Penn State Applied Research Laboratory (PSU-ARL) technicians for demobilization and post-experimental cleanup of the...NAME(S) AND ADDRESS(ES) The Pennsylvania State University Applied Research Labotatory Office of Sponsored Programs 110 Technology Center Building

NPS-SCAT: Systems Engineering and Payload Subsystem Design, Integration, and Testing of NPS’ First CubeSat

DTIC Science & Technology

2010-06-01

Subsystem Design, Integration, and Testing of NPS’ First CubeSat 6. AUTHOR(S) Jenkins, Robert D. IV 5. FUNDING NUMBERS 7. PERFORMING ORGANIZATION NAME(S...AND ADDRESS(ES) Naval Postgraduate School Monterey, CA 93943-5000 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING /MONITORING...Experimental Mission SOIC Small Outline Integrated Circuit SOT Small Outline Transistor SpaceX Space Exploration Technologies Corporation SPI

Mathematical Model of HIF-1 alpha Pathway, Oxygen Transport and Hypoxia

DTIC Science & Technology

2017-09-01

interpret experimental data in terms of underlying mechanisms. Such experiments, if quantitative , can also be used to calibrate and further parameterize...Wing Air Force Research Laboratory Wright-Patterson AFB OH 45433-5707 STINFO COPY Work Unit Manager MATTIE.DAV ID.R.123010 1880 Digitally signed by...MONITORING AGENCY NAME(S) AND ADDRESS(ES) Air Force Materiel Command* Air Force Research Laboratory 711th Human Performance Wing Human Effectiveness

Residualization is not the answer: Rethinking how to address multicollinearity.

PubMed

York, Richard

2012-11-01

Here I show that a commonly used procedure to address problems stemming from collinearity and multicollinearity among independent variables in regression analysis, "residualization", leads to biased coefficient and standard error estimates and does not address the fundamental problem of collinearity, which is a lack of information. I demonstrate this using visual representations of collinearity, hypothetical experimental designs, and analyses of both artificial and real world data. I conclude by noting the importance of examining methodological practices to ensure that their validity can be established based on rational criteria. Copyright © 2012 Elsevier Inc. All rights reserved.

Robustness of high-fidelity Rydberg gates with single-site addressability

NASA Astrophysics Data System (ADS)

Goerz, Michael H.; Halperin, Eli J.; Aytac, Jon M.; Koch, Christiane P.; Whaley, K. Birgitta

2014-09-01

Controlled-phase (cphase) gates can be realized with trapped neutral atoms by making use of the Rydberg blockade. Achieving the ultrahigh fidelities required for quantum computation with such Rydberg gates, however, is compromised by experimental inaccuracies in pulse amplitudes and timings, as well as by stray fields that cause fluctuations of the Rydberg levels. We report here a comparative study of analytic and numerical pulse sequences for the Rydberg cphase gate that specifically examines the robustness of the gate fidelity with respect to such experimental perturbations. Analytical pulse sequences of both simultaneous and stimulated Raman adiabatic passage (STIRAP) are found to be at best moderately robust under these perturbations. In contrast, optimal control theory is seen to allow generation of numerical pulses that are inherently robust within a predefined tolerance window. The resulting numerical pulse shapes display simple modulation patterns and can be rationalized in terms of an interference between distinct two-photon Rydberg excitation pathways. Pulses of such low complexity should be experimentally feasible, allowing gate fidelities of order 99.90-99.99% to be achievable under realistic experimental conditions.

Modeling Intraocular Bacterial Infections

PubMed Central

Astley, Roger A.; Coburn, Phillip S.; Parkunan, Salai Madhumathi; Callegan, Michelle C.

2016-01-01

Bacterial endophthalmitis is an infection and inflammation of the posterior segment of the eye which can result in significant loss of visual acuity. Even with prompt antibiotic, anti-inflammatory and surgical intervention, vision and even the eye itself may be lost. For the past century, experimental animal models have been used to examine various aspects of the pathogenesis and pathophysiology of bacterial endophthalmitis, to further the development of anti-inflammatory treatment strategies, and to evaluate the pharmacokinetics and efficacies of antibiotics. Experimental models allow independent control of many parameters of infection and facilitate systematic examination of infection outcomes. While no single animal model perfectly reproduces the human pathology of bacterial endophthalmitis, investigators have successfully used these models to understand the infectious process and the host response, and have provided new information regarding therapeutic options for the treatment of bacterial endophthalmitis. This review highlights experimental animal models of endophthalmitis and correlates this information with the clinical setting. The goal is to identify knowledge gaps that may be addressed in future experimental and clinical studies focused on improvements in the therapeutic preservation of vision during and after this disease. PMID:27154427

Experimental Models of Ocular Infection with Toxoplasma Gondii

PubMed Central

Dukaczewska, Agata; Tedesco, Roberto; Liesenfeld, Oliver

2015-01-01

Ocular toxoplasmosis is a vision-threatening disease and the major cause of posterior uveitis worldwide. In spite of the continuing global burden of ocular toxoplasmosis, many critical aspects of disease including the therapeutic approach to ocular toxoplasmosis are still under debate. To assist in addressing many aspects of the disease, numerous experimental models of ocular toxoplasmosis have been established. In this article, we present an overview on in vitro, ex vivo, and in vivo models of ocular toxoplasmosis available to date. Experimental studies on ocular toxoplasmosis have recently focused on mice. However, the majority of murine models established so far are based on intraperitoneal and intraocular infection with Toxoplasma gondii. We therefore also present results obtained in an in vivo model using peroral infection of C57BL/6 and NMRI mice that reflects the natural route of infection and mimics the disease course in humans. While advances have been made in ex vivo model systems or larger animals to investigate specific aspects of ocular toxoplasmosis, laboratory mice continue to be the experimental model of choice for the investigation of ocular toxoplasmosis. PMID:26716018

Studying plant–pollinator interactions in a changing climate: A review of approaches1

PubMed Central

Byers, Diane L.

2017-01-01

Plant–pollinator interactions are potentially at risk due to climate change. Because of the spatial and temporal variation associated with the effects of climate change and the responses of both actors, research to assess this interaction requires creative approaches. This review focuses on assessments of plants’ and pollinators’ altered phenology in response to environmental changes, as phenology is one of the key responses. I reviewed research methods with the goal of presenting the wide diversity of available techniques for addressing changes in these interactions. Approaches ranged from use of historical specimens to multisite experimental community studies; while differing in depth of historical information and community interactions, all contribute to assessment of phenology changes. Particularly insightful were those studies that directly assessed the environmental changes across spatial and temporal scales and the responses of plants and pollinators at these scales. Longer-term studies across environmental gradients, potentially with reciprocal transplants, enable an assessment of climate impacts at both scales. While changes in phenology are well studied, the impacts of phenology changes are not. Future research should include approaches to address this gap. PMID:28690933

Enhancing Scientific Foundations to Ensure Reproducibility: A New Paradigm.

PubMed

Hsieh, Terry; Vaickus, Max H; Remick, Daniel G

2018-01-01

Progress in science is dependent on a strong foundation of reliable results. The publish or perish paradigm in research, coupled with an increase in retracted articles from the peer-reviewed literature, is beginning to erode the trust of both the scientific community and the public. The NIH is combating errors by requiring investigators to follow new guidelines addressing scientific premise, experimental design, biological variables, and authentication of reagents. Herein, we discuss how implementation of NIH guidelines will help investigators proactively address pitfalls of experimental design and methods. Careful consideration of the variables contributing to reproducibility helps ensure robust results. The NIH, investigators, and journals must collaborate to ensure that quality science is funded, explored, and published. Copyright © 2018 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Experimental realization of a multiplexed quantum memory with 225 individually accessible memory cells

PubMed Central

Pu, Y-F; Jiang, N.; Chang, W.; Yang, H-X; Li, C.; Duan, L-M

2017-01-01

To realize long-distance quantum communication and quantum network, it is required to have multiplexed quantum memory with many memory cells. Each memory cell needs to be individually addressable and independently accessible. Here we report an experiment that realizes a multiplexed DLCZ-type quantum memory with 225 individually accessible memory cells in a macroscopic atomic ensemble. As a key element for quantum repeaters, we demonstrate that entanglement with flying optical qubits can be stored into any neighboring memory cells and read out after a programmable time with high fidelity. Experimental realization of a multiplexed quantum memory with many individually accessible memory cells and programmable control of its addressing and readout makes an important step for its application in quantum information technology. PMID:28480891

Do school-based interventions focusing on physical activity, fitness, or fundamental movement skill competency produce a sustained impact in these outcomes in children and adolescents? A systematic review of follow-up studies.

PubMed

Lai, Samuel K; Costigan, Sarah A; Morgan, Philip J; Lubans, David R; Stodden, David F; Salmon, Jo; Barnett, Lisa M

2014-01-01

The aim of this systematic review was to determine whether typically developing children and adolescents (aged 3-18 years) who have participated in school-based interventions have sustained outcomes in PA, fitness, and/or FMS. A systematic search of six electronic databases (CINAHL® Plus with Full Text, Ovid MEDLINE®, SPORTDiscus™, Scopus, PsycINFO® and ERIC) was conducted from 1995 to 26 July 2012. Included studies were school-based studies (including randomized controlled trials, longitudinal cohort, quasi-experimental, and experimental) that had a positive effect at post intervention in at least one variable and had a follow-up PA, fitness, or FMS assessment at least 6 months after the post-intervention assessment. Risk of bias assessment was guided by the "Preferred Reporting Items for Systematic Reviews and Meta-Analyses" statement. The search identified 14 articles, and some studies addressed multiple outcomes: 13 articles assessed PA; three assessed fitness; and two assessed FMS. No study in this review met four key methodological criteria that have been shown to influence results, i.e., clarity on the randomization process, assessor blinding, analyzing participants in their original groups, and retaining sufficient participants through the entire study. Three-quarters (ten of 13) of the studies addressing PA, reported PA behavior change maintenance. The length of follow-up ranged from 6 months to 20 years, and the degree of PA difference reported was between 3 and 14 min per day. Only one of the three studies assessing fitness reported a sustained impact, whilst both studies that assessed FMS reported maintenance of effects. It is likely that PA is a sustainable outcome from interventions in children and adolescents, and there is reasonable evidence that interventions of longer than 1 year and interventions that utilize a theoretical model or framework are effective in producing this sustained impact. It would seem probable that FMS are a sustainable outcome in children and adolescents; however, this finding should be viewed with caution given the lack of studies and the risk of bias assessment. More research is needed to assess the sustainability of fitness interventions as this review only included a handful of studies that addressed fitness and only one of these studies found a sustained impact.

A Questionnaire-Based Study on the Perceptions of Canadian Seniors About Cognitive, Social, and Psychological Benefits of Digital Games.

PubMed

Duplàa, Emmanuel; Kaufman, David; Sauvé, Louise; Renaud, Lise

2017-06-01

This study explored the perceptions of seniors who play digital games on the potential benefits of these games and on the factors associated with these perceptions. We developed and administered a questionnaire to a sample of 590 Canadian seniors in British Columbia and Quebec that addressed demographics, digital game practices, and perceived benefits. Results of administering the questionnaire showed that cognitive benefits were reported more frequently than social or psychological benefits. First language and gender were associated with the benefits reported, with fewer Francophones and women reporting benefits. The most important factor found was whether or not they played online, as playing online was associated with greater perceptions of social, as well as cognitive, benefits. Social and cognitive benefits are reported by seniors from playing digital games and should be investigated through future experimental and quasi-experimental research.

Prolonged sleep restriction induces changes in pathways involved in cholesterol metabolism and inflammatory responses.

PubMed

Aho, Vilma; Ollila, Hanna M; Kronholm, Erkki; Bondia-Pons, Isabel; Soininen, Pasi; Kangas, Antti J; Hilvo, Mika; Seppälä, Ilkka; Kettunen, Johannes; Oikonen, Mervi; Raitoharju, Emma; Hyötyläinen, Tuulia; Kähönen, Mika; Viikari, Jorma S A; Härmä, Mikko; Sallinen, Mikael; Olkkonen, Vesa M; Alenius, Harri; Jauhiainen, Matti; Paunio, Tiina; Lehtimäki, Terho; Salomaa, Veikko; Orešič, Matej; Raitakari, Olli T; Ala-Korpela, Mika; Porkka-Heiskanen, Tarja

2016-04-22

Sleep loss and insufficient sleep are risk factors for cardiometabolic diseases, but data on how insufficient sleep contributes to these diseases are scarce. These questions were addressed using two approaches: an experimental, partial sleep restriction study (14 cases and 7 control subjects) with objective verification of sleep amount, and two independent epidemiological cohorts (altogether 2739 individuals) with questions of sleep insufficiency. In both approaches, blood transcriptome and serum metabolome were analysed. Sleep loss decreased the expression of genes encoding cholesterol transporters and increased expression in pathways involved in inflammatory responses in both paradigms. Metabolomic analyses revealed lower circulating large HDL in the population cohorts among subjects reporting insufficient sleep, while circulating LDL decreased in the experimental sleep restriction study. These findings suggest that prolonged sleep deprivation modifies inflammatory and cholesterol pathways at the level of gene expression and serum lipoproteins, inducing changes toward potentially higher risk for cardiometabolic diseases.

Much Ado About (Almost!) Nothing: The Experimental Study of Neutrino Masses and Mixing

NASA Astrophysics Data System (ADS)

Messier, Mark

2009-11-01

Neutrinos have been described by their discoverer Frederick Reines as ``the most tiny quantity of reality ever imagined by a human being.'' Yet these particles which verge on nothingness have had an enormous influence on the past and future evolution of the universe and are the subject of an increasingly active program of experimental physics. In this talk I will review some of the basic properties of neutrinos and summarize the recent results on neutrino masses and mixing from studies of neutrinos produced in the Sun, cosmic rays, reactors, and accelerators including searches for zero neutrino double beta decay. Looking ahead, I will outline the future course of experiments in the U.S., Asia, and Europe which will address the questions of the fundamental character of the neutrino, the hierarchy of their masses, and their matter anti-matter symmetries.

Conceptual and Preliminary Design of a Low-Cost Precision Aerial Delivery System

DTIC Science & Technology

2016-06-01

test results. It includes an analysis of the failure modes encountered during flight experimentation , methodology used for conducting coordinate...and experimentation . Additionally, the current and desired end state of the research is addressed. Finally, this chapter outlines the methodology ...preliminary design phases are utilized to investigate and develop a potentially low-cost alternative to existing systems. Using an Agile methodology

Deep Water Acoustics

DTIC Science & Technology

2016-06-28

Sea, the results of which will support all of the objectives listed above. APPROACH APL-UW employed a combination of experimental measurements, data...APPROACH APL-UW employs a combination of experimental measurements, data analysis, simulations, and theoretical development to address the objectives...RD cases, respectively). In the RI case, the UTP moves back and forth along a curve. In the RD case, the UTP traces out an ellipse. The same is true

Symposium on General Linear Model Approach to the Analysis of Experimental Data in Educational Research (Athens, Georgia, June 29-July 1, 1967). Final Report.

ERIC Educational Resources Information Center

Bashaw, W. L., Ed.; Findley, Warren G., Ed.

This volume contains the five major addresses and subsequent discussion from the Symposium on the General Linear Models Approach to the Analysis of Experimental Data in Educational Research, which was held in 1967 in Athens, Georgia. The symposium was designed to produce systematic information, including new methodology, for dissemination to the…

NASA Lewis 1969 Apprentice Class Graduates

NASA Image and Video Library

1969-11-21

The 1969 class of graduating apprentices pose for a group photograph during a rehearsal ceremony at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The 35 men completed four years of classroom and hands-on training in various aerospace research trades. Center Director Bruce Lundin and President of Cuyahoga Community College Dr. Bernard Silk addressed the graduates at the ceremony. The Ohio State Apprenticeship Council officially accredited them as journeymen. The journeymen specialized in one of the following fields: aerospace laboratory mechanic, aerospace service operator, experimental electronic equipment mechanic, experimental facilities electrician, experimental metal modelmaker, experimental metal worker, research equipment mechanic, research instrumentation mechanic, or utilities mechanic.

A meta-analytic review of corridor effectiveness.

PubMed

Gilbert-Norton, Lynne; Wilson, Ryan; Stevens, John R; Beard, Karen H

2010-06-01

Using corridors for conservation is increasing despite a lack of consensus on their efficacy. Specifically, whether corridors increase movement of plants and animals between habitat fragments has been addressed on a case-by-case basis with mixed results. Because of the growing number of well-designed experiments that have addressed this question, we conducted a meta-analysis to determine whether corridors increase movement; whether corridor effectiveness differs among taxa; how recent changes in experimental design have influenced findings; and whether corridor effectiveness differs between manipulative and natural experiments. To conduct our meta-analysis, we analyzed 78 experiments from 35 studies using a conservative hierarchical Bayesian model that accounts for hierarchical and sampling dependence. We found a highly significant result that corridors increase movement between habitat patches by approximately 50% compared to patches that are not connected with corridors. We found that corridors were more important for the movement of invertebrates, nonavian vertebrates, and plants than they were for birds. Recent methodological advances in corridor experiments, such as controlling for the area added by corridors, did not influence whether corridors increased movement, whereas controlling for the distance between source and connected or unconnected recipient patches decreased movement through corridors. After controlling for taxa differences and whether studies controlled for distance in experimental design, we found that natural corridors (those existing in landscapes prior to the study) showed more movement than manipulated corridors (those created and maintained for the study). Our results suggest that existing corridors increase species movement in fragmented landscapes and that efforts spent on maintaining and creating corridors are worthwhile.

Skin cancer interventions across the cancer control continuum: A review of experimental evidence (1/1/2000-6/30/2015) and future research directions.

PubMed

Geller, Alan C; Dickerman, Barbra A; Taber, Jennifer M; Dwyer, Laura A; Hartman, Anne M; Perna, Frank M

2018-06-01

While the general efficacy of skin cancer interventions have been reviewed, employing the cancer control continuum would be useful to identify research gaps at specific cancer control points. We characterized the intervention evidence base for specific behavioral targets (e.g., tanning, sun protection, screening) and clinically related targets (e.g., sunburn, skin exams, cancers) at each point in the cancer control continuum. The review included articles published from 1/1/2000-6/30/15 that had an experimental design and targeted behavioral intervention in skin cancer (e.g., specific behaviors or clinically related targets). The search yielded 86 articles, including seven dissemination studies. Of the 79 non-dissemination studies, 57 exclusively targeted primary prevention behaviors, five exclusively targeted screening, 10 targeted both detection and prevention, and eight addressed cancer survivorship. Among prevention studies (n=67), 29 (43%) targeted children and 38 (57%) targeted adults. Of the 15 screening studies, nine targeted high-risk groups (e.g., men aged ≥50 years) and six targeted the general population. Although research has focused on skin cancer prevention, empirically validated interventions are still needed for youth engaged in indoor tanning and for behavioral interventions to pursue change in clinically relevant targets. Research must also address detection among those at highest risk for skin cancer, amelioration of emotional distress attendant to diagnosis and treatment, and survivorship concerns. We discuss essential qualities and opportunities for intervention development and translational research to inform the field. Copyright © 2018 Elsevier Inc. All rights reserved.

Recovery of microbial communities and carbon cycling processes following drought manipulation in southern California

NASA Astrophysics Data System (ADS)

Allison, S. D.; Martiny, J. B. H.; Martiny, A.; Berlemont, R.; Treseder, K. K.; Goulden, M.; Brodie, E.

2016-12-01

Predicting the functioning of microbial communities under changing environmental conditions remains a key challenge in Earth system science. Metagenomics and other high-throughput molecular approaches can help address this challenge by revealing the functional potential of microbial communities. We coupled metagenomics with models and experimental manipulations to address microbial responses to drought in a California grassland ecosystem along with the consequences for carbon cycling. We developed an approach for extracting trait information from metagenomic data and asked: 1) What is the phylogenetic structure of drought response traits? 2) What is the relationship between these traits and those involved in carbohydrate degradation? 3) How do both classes of traits vary seasonally and with precipitation manipulation? 4) How resilient are these traits in the face of perturbation? We found that drought response traits are phylogenetically conserved at an equivalent of 5-8% ribosomal RNA gene sequence dissimilarity. Experimental drought treatment selected for the genetic potential to degrade starch, xylan, and mixed polysaccharides, suggesting a link between drought response and carbon cycling traits. In addition, microbial communities exposed to experimental drought showed a reduced potential to degrade plant biomass. Particularly among bacteria, seasonal drought had a larger impact on microbial composition, abundance, and carbohydrate-degrading genes compared to experimental drought. Bacterial communities were also more resilient to drought perturbation than fungal communities, which showed legacies of drought perturbation for up to three years. Altogether, these findings imply that microbial communities exhibit trait diversity that facilitates resilience but with substantial time lags and consequences for carbon turnover. This information is being used to inform new trait-based models that address the challenge of predicting microbial functioning under precipitation change.

Deterministic analysis of processes at corroding metal surfaces and the study of electrochemical noise in these systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Latanision, R.M.

1990-12-01

Electrochemical corrosion is pervasive in virtually all engineering systems and in virtually all industrial circumstances. Although engineers now understand how to design systems to minimize corrosion in many instances, many fundamental questions remain poorly understood and, therefore, the development of corrosion control strategies is based more on empiricism than on a deep understanding of the processes by which metals corrode in electrolytes. Fluctuations in potential, or current, in electrochemical systems have been observed for many years. To date, all investigations of this phenomenon have utilized non-deterministic analyses. In this work it is proposed to study electrochemical noise from a deterministicmore » viewpoint by comparison of experimental parameters, such as first and second order moments (non-deterministic), with computer simulation of corrosion at metal surfaces. In this way it is proposed to analyze the origins of these fluctuations and to elucidate the relationship between these fluctuations and kinetic parameters associated with metal dissolution and cathodic reduction reactions. This research program addresses in essence two areas of interest: (a) computer modeling of corrosion processes in order to study the electrochemical processes on an atomistic scale, and (b) experimental investigations of fluctuations in electrochemical systems and correlation of experimental results with computer modeling. In effect, the noise generated by mathematical modeling will be analyzed and compared to experimental noise in electrochemical systems. 1 fig.« less

Geographical and experimental contexts modulate the effect of warming on top-down control: a meta-analysis.

PubMed

Marino, Nicholas Dos Anjos Cristiano; Romero, Gustavo Quevedo; Farjalla, Vinicius Fortes

2018-03-01

Ecologists have extensively investigated the effect of warming on consumer-resource interactions, with experiments revealing that warming can strengthen, weaken or have no net effect on top-down control of resources. These experiments have inspired a body of theoretical work to explain the variation in the effect of warming on top-down control. However, there has been no quantitative attempt to reconcile theory with outcomes from empirical studies. To address the gap between theory and experiment, we performed a meta-analysis to examine the combined effect of experimental warming and top-down control on resource biomass and determined potential sources of variation across experiments. We show that differences in experimental outcomes are related to systematic variation in the geographical distribution of studies. Specifically, warming strengthened top-down control when experiments were conducted in colder regions, but had the opposite effect in warmer regions. Furthermore, we found that differences in the thermoregulation strategy of the consumer and openness of experimental arenas to dispersal can contribute to some deviation from the overall geographical pattern. These results reconcile empirical findings and support the expectation of geographical variation in the response of consumer-resource interactions to warming. © 2018 John Wiley & Sons Ltd/CNRS.

Development of an experimental approach to study coupled soil-plant-atmosphere processes using plant analogs

NASA Astrophysics Data System (ADS)

Trautz, Andrew C.; Illangasekare, Tissa H.; Rodriguez-Iturbe, Ignacio; Heck, Katharina; Helmig, Rainer

2017-04-01

The atmosphere, soils, and vegetation near the land-atmosphere interface are in a state of continuous dynamic interaction via a myriad of complex interrelated feedback processes which collectively, remain poorly understood. Studying the fundamental nature and dynamics of such processes in atmospheric, ecological, and/or hydrological contexts in the field setting presents many challenges; current experimental approaches are an important factor given a general lack of control and high measurement uncertainty. In an effort to address these issues and reduce overall complexity, new experimental design considerations (two-dimensional intermediate-scale coupled wind tunnel-synthetic aquifer testing using synthetic plants) for studying soil-plant-atmosphere continuum soil moisture dynamics are introduced and tested in this study. Validation of these experimental considerations, particularly the adoption of synthetic plants, is required prior to their application in future research. A comparison of three experiments with bare soil surfaces or transplanted with a Stargazer lily/limestone block was used to evaluate the feasibility of the proposed approaches. Results demonstrate that coupled wind tunnel-porous media experimentation, used to simulate field conditions, reduces complexity, and enhances control while allowing fine spatial-temporal resolution measurements to be made using state-of-the-art technologies. Synthetic plants further help reduce system complexity (e.g., airflow) while preserving the basic hydrodynamic functions of plants (e.g., water uptake and transpiration). The trends and distributions of key measured atmospheric and subsurface spatial and temporal variables (e.g., soil moisture, relative humidity, temperature, air velocity) were comparable, showing that synthetic plants can be used as simple, idealized, nonbiological analogs for living vegetation in fundamental hydrodynamic studies.

Dynamic Scattering Mode LCDs

NASA Astrophysics Data System (ADS)

Bahadur, Birendra

The following sections are included: * INTRODUCTION * CELL DESIGNING * EXPERIMENTAL OBSERVATIONS IN NEMATICS RELATED WITH DYNAMIC SCATTERING * Experimental Observations at D.C. Field and Electrode Effects * Experimental Observation at Low Frequency A.C. Fields * Homogeneously Aligned Nematic Regime * Williams Domains * Dynamic Scattering * Experimental Observation at High Frequency A.C. Field * Other Experimental Observations * THEORETICAL INTERPRETATIONS * Felici Model * Carr-Helfrich Model * D.C. Excitation * Dubois-Violette, de Gennes and Parodi Model * Low Freqency or Conductive Regime * High Frequency or Dielectric Regime * DYNAMIC SCATTERING IN SMECRIC A PHASE * ELECTRO-OPTICAL CHARACTERISTICS AND LIMITATIONS * Contrast Ratio vs. Voltage, Viewing Angle, Cell Gap, Wavelength and Temperature * Display Current vs. Voltage, Cell Gap and Temperature * Switching Time * Effect of Alignment * Effect of Conductivity, Temperature and Frequency * Addressing of DSM LCDs * Limitations of DSM LCDs * ACKNOWLEDGEMENTS * REFERENCES

A comprehensive combined experimental and computational framework for pre-clinical wear simulation of total knee replacements.

PubMed

Abdelgaied, A; Fisher, J; Jennings, L M

2018-02-01

A more robust pre-clinical wear simulation framework is required in order to simulate wider and higher ranges of activities, observed in different patient populations such as younger more active patients. Such a framework will help to understand and address the reported higher failure rates for younger and more active patients (National_Joint_Registry, 2016). The current study has developed and validated a comprehensive combined experimental and computational framework for pre-clinical wear simulation of total knee replacements (TKR). The input mechanical (elastic modulus and Poisson's ratio) and wear parameters of the moderately cross-linked ultra-high molecular weight polyethylene (UHMWPE) bearing material were independently measured from experimental studies under realistic test conditions, similar to the loading conditions found in the total knee replacements. The wear predictions from the computational wear simulation were validated against the direct experimental wear measurements for size 3 Sigma curved total knee replacements (DePuy, UK) in an independent experimental wear simulation study under three different daily activities; walking, deep squat, and stairs ascending kinematic conditions. The measured compressive mechanical properties of the moderately cross-linked UHMWPE material were more than 20% lower than that reported in the literature under tensile test conditions. The pin-on-plate wear coefficient of moderately cross-linked UHMWPE was significantly dependant of the contact stress and the degree of cross-shear at the articulating surfaces. The computational wear predictions for the TKR from the current framework were consistent and in a good agreement with the independent full TKR experimental wear simulation measurements, with 0.94 coefficient of determination of the framework. In addition, the comprehensive combined experimental and computational framework was able to explain the complex experimental wear trends from the three different daily activities investigated. Therefore, such a framework can be adopted as a pre-clinical simulation approach to optimise different designs, materials, as well as patient's specific total knee replacements for a range of activities. Copyright © 2017. Published by Elsevier Ltd.

Experimental Progress Toward Detection and Identification of Electromagnetically Complex Structures

DTIC Science & Technology

2008-12-01

M. Jaenisch and J. W. Handley Amtec Corporation Huntsville, Alabama 35816-3429 T.A. Baginski and A.S. Hodel Auburn University Auburn, Alabama...ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Amtec ...transmitter power is relatively low; consequently, our target is entirely above ground for now. Measurements are conducted at the Amtec Outdoor Test

Exploratory Experimental Investigation of a Wave Propeller

DTIC Science & Technology

1992-03-01

ORGANIZATION 6b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION Naval Postgraduate School (if appl able) Naval Postgraduate School 6c. ADDRESS (City... SYMBOL 9. PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ORGANIZATION (ff applicable) Bc ADDRESS (City, State, and ZIP Code) 10- SOURCE OF FUNDING...UNCLASSIFIED 22a. NAME OF RESPONSIBLE INDIVIDUAL 22b. TELEPHONE (Include Area code) 22c. OFFICE SYMBOL Max F. Platter (408) 646-2058 AA/PL DD FORM 1473,84

Nitrogen Solubility in Adipose Tissues of Diving Animals: Implications for Human Divers and for Modeling Diving Physiology

DTIC Science & Technology

2016-11-01

ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION Biology & Marine Biology , UNCW REPORT NUMBER 601 S. College Road Wi lmington, NC...Information PI: Dr. Heather Koopman Institution: Biology & Marine Biology , University of North Carolina Wilmington Award #: N000141210442 Title...both graduate and undergraduate) • 1 paper published in Journal of Experimental Biology (and picked up by the media; see X. G. below); 3 additional

Three-dimensional passive sensing photon counting for object classification

NASA Astrophysics Data System (ADS)

Yeom, Seokwon; Javidi, Bahram; Watson, Edward

2007-04-01

In this keynote address, we address three-dimensional (3D) distortion-tolerant object recognition using photon-counting integral imaging (II). A photon-counting linear discriminant analysis (LDA) is discussed for classification of photon-limited images. We develop a compact distortion-tolerant recognition system based on the multiple-perspective imaging of II. Experimental and simulation results have shown that a low level of photons is sufficient to classify out-of-plane rotated objects.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dracoulis, G. D.; Walker, P. M.; Kondev, F. G.

Here, the structure of nuclear isomeric states is reviewed in the context of their role in contemporary nuclear physics research. Emphasis is given to high-spin isomers in heavy nuclei, with A ≳ 150. The possibility to exploit isomers to study some of the most exotic nuclei is a recurring theme. In spherical nuclei, the role of octupole collectivity is discussed in detail, while in deformed nuclei the limitations of the K quantum number are addressed. Isomer targets and isomer beams are considered, along with applications related to energy storage, astrophysics, medicine, and experimental advances.

Overview of the recent DiMES and MiMES experiments in DIII-D

NASA Astrophysics Data System (ADS)

Rudakov, D. L.; Wong, C. P. C.; Litnovsky, A.; Wampler, W. R.; Boedo, J. A.; Brooks, N. H.; Fenstermacher, M. E.; Groth, M.; Hollmann, E. M.; Jacob, W.; Krasheninnikov, S. I.; Krieger, K.; Lasnier, C. J.; Leonard, A. W.; McLean, A. G.; Marot, M.; Moyer, R. A.; Petrie, T. W.; Philipps, V.; Smirnov, R. D.; Stangeby, P. C.; Watkins, J. G.; West, W. P.; Yu, J. H.

2009-12-01

Divertor and midplane material evaluation systems (DiMES and MiMES) in the DIII-D tokamak are used to address a variety of plasma-material interaction (PMI) issues relevant to ITER. Among the topics studied are carbon erosion and re-deposition, hydrogenic retention in the gaps between plasma-facing components (PFCs), deterioration of diagnostic mirrors from carbon deposition and techniques to mitigate that deposition, and dynamics and transport of dust. An overview of the recent experimental results is presented.

Mathematical model of biological order state or syndrome in traditional Chinese medicine: based on electromagnetic radiation within the human body.

PubMed

Han, Jinxiang; Huang, Jinzhao

2012-03-01

In this study, based on the resonator model and exciplex model of electromagnetic radiation within the human body, mathematical model of biological order state, also referred to as syndrome in traditional Chinese medicine, was established and expressed as: "Sy = v/ 1n(6I + 1)". This model provides the theoretical foundation for experimental research addressing the order state of living system, especially the quantitative research syndrome in traditional Chinese medicine.

The genetics and cell biology of fertilization.

PubMed

Geldziler, Brian D; Marcello, Matthew R; Shakes, Diane C; Singson, Andrew

2011-01-01

Although the general events surrounding fertilization in many species are well described, the molecular underpinnings of fertilization are still poorly understood. Caenorhabditis elegans has emerged as a powerful model system for addressing the molecular and cell biological mechanism of fertilization. A primary advantage is the ability to isolate and propagate mutants that effect gametes and no other cells. This chapter provides conceptual guidelines for the identification, maintenance, and experimental approaches for the study fertility mutants. Copyright © 2011 Elsevier Inc. All rights reserved.

System Theory and Physiological Processes.

PubMed

Jones, R W

1963-05-03

Engineers and physiologists working together in experimental and theoretical studies predict that the application of system analysis to biological processes will increase understanding of these processes and broaden the base of system theory. Richard W. Jones, professor of electrical engineering at Northwestern University, Evanston, Illinois, and John S. Gray, professor of physiology at Northwestern's Medical School, discuss these developments. Their articles are adapted from addresses delivered in Chicago in November 1962 at the 15th Annual Conference on Engineering in Medicine and Biology.

Investigations of microwave plasmas - Applications in electrothermal thruster systems

NASA Technical Reports Server (NTRS)

Haraburda, Scott S.; Hawley, Martin C.

1989-01-01

Experimental studies which have been conducted to develop understanding of plasma processes used for spacecraft propulsion are reviewed. The techniques discussed are calorimetry and volume measurements using the TM 011 and TM 012 modes in the microwave cavity system. The use of plasmas in electrical propulsion and microwave induction is reviewed. Plasma containment, microwave power production, energy distribution, and the pressure and flow dependence of the energy distribution are addressed. The plasma dimensions and their dependence on pressure, flow, and power are considered.

Investigations of microwave plasmas - Applications in electrothermal thruster systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Haraburda, S.S.; Hawley, M.C.

1989-01-01

Experimental studies which have been conducted to develop understanding of plasma processes used for spacecraft propulsion are reviewed. The techniques discussed are calorimetry and volume measurements using the TM 011 and TM 012 modes in the microwave cavity system. The use of plasmas in electrical propulsion and microwave induction is reviewed. Plasma containment, microwave power production, energy distribution, and the pressure and flow dependence of the energy distribution are addressed. The plasma dimensions and their dependence on pressure, flow, and power are considered. 10 refs.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cournia, Zoe; Allen, Toby W.; Andricioaei, Ioan

It is fundamental for the flourishing biological cells that membrane proteins mediate the process. Membrane-embedded transporters move ions and larger solutes across membranes; receptors mediate communication between the cell and its environment and membrane-embedded enzymes catalyze chemical reactions. Understanding these mechanisms of action requires knowledge of how the proteins couple to their fluid, hydrated lipid membrane environment. Here, we present here current studies in computational and experimental membrane protein biophysics, and show how they address outstanding challenges in understanding the complex environmental effects on the structure, function, and dynamics of membrane proteins.

Rapid Aluminum Nanoparticle Production by Milling in NH3 and CH3NH2 Atmospheres: An Experimental and Theoretical Study

DTIC Science & Technology

2015-07-01

REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 Public reporting burden for this collection of information is estimated to average 1...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 1 July 2015 2. REPORT TYPE...ABSTRACT Unclassified c. THIS PAGE Unclassified SAR 105 19b. TELEPHONE NO (include area code) N/A Standard Form 298 (Rev. 8-98

Experimental study on behaviors of dielectric elastomer based on acrylonitrile butadiene rubber

NASA Astrophysics Data System (ADS)

An, Kuangjun; Chuc, Nguyen Huu; Kwon, Hyeok Yong; Phuc, Vuong Hong; Koo, Jachoon; Lee, Youngkwan; Nam, Jaedo; Choi, Hyouk Ryeol

2010-04-01

Previously, the dielectric elastomer based on Acrylonitrile Butadiene Rubber (NBR), called synthetic elastomer has been reported by our group. It has the advantages that its characteristics can be modified according to the requirements of performances, and thus, it is applicable to a wide variety of applications. In this paper, we address the effects of additives and vulcanization conditions on the overall performance of synthetic elastomer. In the present work, factors to have effects on the performances are extracted, e.g additives such as dioctyl phthalate (DOP), barium titanium dioxide (BaTiO3) and vulcanization conditions such as dicumyl peroxide (DCP), cross-linking times. Also, it is described how the performances can be optimized by using DOE (Design of Experiments) technique and experimental results are analyzed by ANOVA (Analysis of variance).

What do we learn about development from baby robots?

PubMed

Oudeyer, Pierre-Yves

2017-01-01

Understanding infant development is one of the great scientific challenges of contemporary science. In addressing this challenge, robots have proven useful as they allow experimenters to model the developing brain and body and understand the processes by which new patterns emerge in sensorimotor, cognitive, and social domains. Robotics also complements traditional experimental methods in psychology and neuroscience, where only a few variables can be studied at the same time. Moreover, work with robots has enabled researchers to systematically explore the role of the body in shaping the development of skill. All told, this work has shed new light on development as a complex dynamical system. WIREs Cogn Sci 2017, 8:e1395. doi: 10.1002/wcs.1395 For further resources related to this article, please visit the WIREs website. © 2016 Wiley Periodicals, Inc.

Mutual interactions of redox couples via electron exchange in silicate melts - Models for geochemical melt systems

NASA Technical Reports Server (NTRS)

Schreiber, Henry D.; Merkel, Robert C., Jr.; Schreiber, V. Lea; Balazs, G. Bryan

1987-01-01

The mutual interactions via electron exchange of redox couples in glass-forming melts were investigated both theoretically and experimentally. A thermodynamic approach for considering the mutual interactions leads to conclusion that the degree of mutual interaction in the melt should be proportional in part to the difference in relative reduction potentials of the interacting redox couples. Experimental studies verify this conclusion for numerous redox couples in several composition/temperature/oxygen fugacity regimes. Geochemical systems simultaneously possess many potentially multivalent elements; the stabilized redox states in the resulting magmas can be explained in part by mutual interactions and by redox buffering through the central Fe(III)- Fe(II) couples in the melts. The significance of these results for basaltic magmas of the earth, moon, and meteorites is addressed.

New Issues for New Methods: Ethical and Editorial Challenges for an Experimental Philosophy.

PubMed

Polonioli, Andrea

2017-08-01

This paper examines a constellation of ethical and editorial issues that have arisen since philosophers started to conduct, submit and publish empirical research. These issues encompass concerns over responsible authorship, fair treatment of human subjects, ethicality of experimental procedures, availability of data, unselective reporting and publishability of research findings. This study aims to assess whether the philosophical community has as yet successfully addressed such issues. To do so, the instructions for authors, submission process and published research papers of 29 main journals in philosophy have been considered and analyzed. In light of the evidence reported here, it is argued that the philosophical community has as yet failed to properly tackle such issues. The paper also delivers some recommendations for authors, reviewers and editors in the field.

Attrition in Smoking Cessation Intervention Studies: A Systematic Review.

PubMed

Belita, Emily; Sidani, Souraya

2015-12-01

Withdrawal of participants from intervention studies has dire methodological and clinical consequences. Attrition rates in smoking cessation studies have been found to be particularly high. Identifying factors that contribute to attrition may inform strategies to address the problem and prevent its consequences. This systematic review had 2 objectives: to report attrition rates, and to identify factors that influence attrition of adult smokers participating in smoking cessation intervention studies. Inclusion criteria were (1) published between 1980 and 2015; (2) experimental or quasi-experimental design; (3) pharmacological, educational, or behavioural intervention; (4) target population of adult smokers; (5) examination of attrition rate; and (6) exploration of factors associated with attrition and/or of reasons given by participants for withdrawing. These criteria were met by 10 studies. Attrition rates ranged from 10.8% to 77%. A small number of demographic, clinical, behavioural, health, health-related beliefs, and logistical factors were related to attrition. The report of high attrition rates underlines the importance of incorporating strategies to minimize attrition in smoking cessation studies. Strategies to reduce attrition are proposed. Copyright© by Ingram School of Nursing, McGill University.

A Robust Adaptive Autonomous Approach to Optimal Experimental Design

NASA Astrophysics Data System (ADS)

Gu, Hairong

Experimentation is the fundamental tool of scientific inquiries to understand the laws governing the nature and human behaviors. Many complex real-world experimental scenarios, particularly in quest of prediction accuracy, often encounter difficulties to conduct experiments using an existing experimental procedure for the following two reasons. First, the existing experimental procedures require a parametric model to serve as the proxy of the latent data structure or data-generating mechanism at the beginning of an experiment. However, for those experimental scenarios of concern, a sound model is often unavailable before an experiment. Second, those experimental scenarios usually contain a large number of design variables, which potentially leads to a lengthy and costly data collection cycle. Incompetently, the existing experimental procedures are unable to optimize large-scale experiments so as to minimize the experimental length and cost. Facing the two challenges in those experimental scenarios, the aim of the present study is to develop a new experimental procedure that allows an experiment to be conducted without the assumption of a parametric model while still achieving satisfactory prediction, and performs optimization of experimental designs to improve the efficiency of an experiment. The new experimental procedure developed in the present study is named robust adaptive autonomous system (RAAS). RAAS is a procedure for sequential experiments composed of multiple experimental trials, which performs function estimation, variable selection, reverse prediction and design optimization on each trial. Directly addressing the challenges in those experimental scenarios of concern, function estimation and variable selection are performed by data-driven modeling methods to generate a predictive model from data collected during the course of an experiment, thus exempting the requirement of a parametric model at the beginning of an experiment; design optimization is performed to select experimental designs on the fly of an experiment based on their usefulness so that fewest designs are needed to reach useful inferential conclusions. Technically, function estimation is realized by Bayesian P-splines, variable selection is realized by Bayesian spike-and-slab prior, reverse prediction is realized by grid-search and design optimization is realized by the concepts of active learning. The present study demonstrated that RAAS achieves statistical robustness by making accurate predictions without the assumption of a parametric model serving as the proxy of latent data structure while the existing procedures can draw poor statistical inferences if a misspecified model is assumed; RAAS also achieves inferential efficiency by taking fewer designs to acquire useful statistical inferences than non-optimal procedures. Thus, RAAS is expected to be a principled solution to real-world experimental scenarios pursuing robust prediction and efficient experimentation.

The Immunomodulation and Anti-Inflammatory Effects of Garlic Organosulfur Compounds in Cancer Chemoprevention

PubMed Central

Schäfer, Georgia; Kaschula, Catherine H.

2014-01-01

Garlic (Allium sativum) has been used for centuries as a prophylactic and therapeutic medicinal agent. Importantly, garlic has been suggested to have both cancer-preventive potential as well as significant enhancing effects on the immune system. While these observations are supported experimentally both in vitro and in vivo, the impact of garlic in assisting the immune system in the prevention of cancer still lacks experimental confirmation. Studies addressing the immunomodulatory effects of garlic reveal conflicting data as to pro- or anti-inflammatory responses depending on the particular experimental set-ups and the garlic preparation used (i.e. garlic extract versus chemically pure garlic compounds). Here we provide an overview of the chemistry of the major garlic organosulfur compounds, summarize the current understanding and propose a link between the immunomodulating activity of garlic and the prevention of cancer. We hypothesize that garlic rather elicits anti-inflammatory and anti-oxidative responses that aid in priming the organism towards eradication of an emerging tumor. PMID:24237225

Transverse parton momenta in single inclusive hadron production in e+ e- annihilation processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boglione, M.; Gonzalez-Hernandez, J. O.; Taghavi, R.

Here, we study the transverse momentum distributions of single inclusive hadron production in e+e- annihilation processes. Although the only available experimental data are scarce and quite old, we find that the fundamental features of transverse momentum dependent (TMD) evolution, historically addressed in Drell–Yan processes and, more recently, in Semi-inclusive deep inelastic scattering processes, are visible in e+e- annihilations as well. Interesting effects related to its non-perturbative regime can be observed. We test two different parameterizations for the p more » $$\\perp$$ dependence of the cross section: the usual Gaussian distribution and a power-law model. We find the latter to be more appropriate in describing this particular set of experimental data, over a relatively large range of p $$\\perp$$ values. We use this model to map some of the features of the data within the framework of TMD evolution, and discuss the caveats of this and other possible interpretations, related to the one-dimensional nature of the available experimental data.« less

Robust model-based analysis of single-particle tracking experiments with Spot-On

PubMed Central

Grimm, Jonathan B; Lavis, Luke D

2018-01-01

Single-particle tracking (SPT) has become an important method to bridge biochemistry and cell biology since it allows direct observation of protein binding and diffusion dynamics in live cells. However, accurately inferring information from SPT studies is challenging due to biases in both data analysis and experimental design. To address analysis bias, we introduce ‘Spot-On’, an intuitive web-interface. Spot-On implements a kinetic modeling framework that accounts for known biases, including molecules moving out-of-focus, and robustly infers diffusion constants and subpopulations from pooled single-molecule trajectories. To minimize inherent experimental biases, we implement and validate stroboscopic photo-activation SPT (spaSPT), which minimizes motion-blur bias and tracking errors. We validate Spot-On using experimentally realistic simulations and show that Spot-On outperforms other methods. We then apply Spot-On to spaSPT data from live mammalian cells spanning a wide range of nuclear dynamics and demonstrate that Spot-On consistently and robustly infers subpopulation fractions and diffusion constants. PMID:29300163

Robust model-based analysis of single-particle tracking experiments with Spot-On.

PubMed

Hansen, Anders S; Woringer, Maxime; Grimm, Jonathan B; Lavis, Luke D; Tjian, Robert; Darzacq, Xavier

2018-01-04

Single-particle tracking (SPT) has become an important method to bridge biochemistry and cell biology since it allows direct observation of protein binding and diffusion dynamics in live cells. However, accurately inferring information from SPT studies is challenging due to biases in both data analysis and experimental design. To address analysis bias, we introduce 'Spot-On', an intuitive web-interface. Spot-On implements a kinetic modeling framework that accounts for known biases, including molecules moving out-of-focus, and robustly infers diffusion constants and subpopulations from pooled single-molecule trajectories. To minimize inherent experimental biases, we implement and validate stroboscopic photo-activation SPT (spaSPT), which minimizes motion-blur bias and tracking errors. We validate Spot-On using experimentally realistic simulations and show that Spot-On outperforms other methods. We then apply Spot-On to spaSPT data from live mammalian cells spanning a wide range of nuclear dynamics and demonstrate that Spot-On consistently and robustly infers subpopulation fractions and diffusion constants. © 2018, Hansen et al.

Transverse parton momenta in single inclusive hadron production in e+ e- annihilation processes

DOE PAGES

Boglione, M.; Gonzalez-Hernandez, J. O.; Taghavi, R.

2017-06-17

Here, we study the transverse momentum distributions of single inclusive hadron production in e+e- annihilation processes. Although the only available experimental data are scarce and quite old, we find that the fundamental features of transverse momentum dependent (TMD) evolution, historically addressed in Drell–Yan processes and, more recently, in Semi-inclusive deep inelastic scattering processes, are visible in e+e- annihilations as well. Interesting effects related to its non-perturbative regime can be observed. We test two different parameterizations for the p more » $$\\perp$$ dependence of the cross section: the usual Gaussian distribution and a power-law model. We find the latter to be more appropriate in describing this particular set of experimental data, over a relatively large range of p $$\\perp$$ values. We use this model to map some of the features of the data within the framework of TMD evolution, and discuss the caveats of this and other possible interpretations, related to the one-dimensional nature of the available experimental data.« less

Studying brain-regulation of immunity with optogenetics and chemogenetics; A new experimental platform.

PubMed

Ben-Shaanan, Tamar; Schiller, Maya; Rolls, Asya

2017-10-01

The interactions between the brain and the immune system are bidirectional. Nevertheless, we have far greater understanding of how the immune system affects the brain than how the brain affects immunity. New technological developments such as optogenetics and chemogenetics (using DREADDs; Designer Receptors Exclusively Activated by Designer Drugs) can bridge this gap in our understanding, as they enable an unprecedented mechanistic and systemic analysis of the communication between the brain and the immune system. In this review, we discuss new experimental approaches for revealing neuronal circuits that can participate in regulation of immunity. In addition, we discuss methods, specifically optogenetics and chemogenetics, that enable targeted neuronal manipulation to reveal how different brain regions affect immunity. We describe how these techniques can be used as an experimental platform to address fundamental questions in psychoneuroimmunology and to understand how neuronal circuits associate with different psychological states can affect physiology. Copyright © 2016 Elsevier Inc. All rights reserved.

Biomimetic materials in the utility industry: A program plan for research opportunities, volume 2. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richman, R.H.; McNaughton, W.P.

1996-09-01

This report is the second of a two-volume set addressing the state-of-the-art and outlook for the application of biomimetic materials. The first volume examined achievements in mimicking novel aspects of biological systems in five broad categories: (1) Mimicking of Natural Material Designs, (2) Biomimetic Materials Processing, (3) Artificial Photosynthesis, (4) Biomimetic Molecular Electronics, and (5) Biomimetic Catalysis. Each topic was examined as to current activities and approaches, key aspects, unresolved issues, and implications for the power industry. Key researchers, their organizations, the main thrusts of investigation, achievements, and funding agencies were also summarized. This volume highlights opportunities for future researchmore » activities in biomimetics that could be valuable to the U.S. utility industry. Nineteen specific research projects have been identified. These opportunities are outlined in four classes: (1) technology awareness, (2) modeling and experimental studies, (3) state-of-the-art and outlook studies: developing experimental plans, and (4) concept feasibility studies.« less

Standardized classroom management program: Social validation and replication studies in Utah and Oregon

PubMed Central

Greenwood, Charles R.; Hops, Hyman; Walker, Hill M.; Guild, Jacqueline J.; Stokes, Judith; Young, K. Richard; Keleman, Kenneth S.; Willardson, Marlyn

1979-01-01

A comprehensive validation study was conducted of the Program for Academic Survival Skills (PASS), a consultant-based, teacher-mediated program for student classroom behavior. The study addressed questions related to: (a) brief consultant training, (b) subsequent teacher training by consultants using PASS manuals, (c) contrasts between PASS experimental teachers and students and equivalent controls on measures of teacher management skills, student classroom behavior, teacher ratings of student problem behaviors, and academic achievement, (d) reported satisfaction of participants, and (e) replication of effects across two separate school sites. Results indicated that in both sites significant effects were noted in favor of the PASS experimental group for (a) teacher approval, (b) student appropriate classroom behavior, and (c) four categories of student inappropriate behavior. Program satisfaction ratings of students, teachers, and consultants were uniformly positive, and continued use of the program was reported a year later. Discussion focused upon issues of cost-effectiveness, differential site effects, and the relationship between appropriate classroom behavior and academic achievement. PMID:16795604

Violent Video Games Don't Increase Hostility in Teens, but They Do Stress Girls Out.

PubMed

Ferguson, Christopher J; Trigani, Benjamin; Pilato, Steven; Miller, Stephanie; Foley, Kimberly; Barr, Hayley

2016-03-01

The impact of violent video games (VVGs) on youth remains unclear given inconsistent results in past literature. Most previous experimental studies have been done with college students, not youth. The current study examined the impact of VVGs in an experimental study of teens (12-18). Participants were randomized to play either a violent or non-violent video game. Teens also reported their levels of stress and hostility both before and after video game play. Hostility levels neither decreased nor increased following violent game play, and Bayesian analyzes confirmed that results are supportive of the null hypothesis. By contrast, VVG exposure increased stress, but only for girls. The impact of VVGs on teen hostility is minimal. However, players unfamiliar with such games may find them unpleasant. These results are put into the context of Uses and Gratifications Theory with suggestions for how medical professionals should address the issue of VVG play with concerned parents.

Gene expression profiling--Opening the black box of plant ecosystem responses to global change

DOE Office of Scientific and Technical Information (OSTI.GOV)

Leakey, A.D.B.; Ainsworth, E.A.; Bernard, S.M.

The use of genomic techniques to address ecological questions is emerging as the field of genomic ecology. Experimentation under environmentally realistic conditions to investigate the molecular response of plants to meaningful changes in growth conditions and ecological interactions is the defining feature of genomic ecology. Since the impact of global change factors on plant performance are mediated by direct effects at the molecular, biochemical and physiological scales, gene expression analysis promises important advances in understanding factors that have previously been consigned to the 'black box' of unknown mechanism. Various tools and approaches are available for assessing gene expression in modelmore » and non-model species as part of global change biology studies. Each approach has its own unique advantages and constraints. A first generation of genomic ecology studies in managed ecosystems and mesocosms have provided a testbed for the approach and have begun to reveal how the experimental design and data analysis of gene expression studies can be tailored for use in an ecological context.« less

Dynamic diamond anvil cell (dDAC): A novel device for studying the dynamic-pressure properties of materials

NASA Astrophysics Data System (ADS)

Evans, William J.; Yoo, Choong-Shik; Lee, Geun Woo; Cynn, Hyunchae; Lipp, Magnus J.; Visbeck, Ken

2007-07-01

We have developed a unique device, a dynamic diamond anvil cell (dDAC), which repetitively applies a time-dependent load/pressure profile to a sample. This capability allows studies of the kinetics of phase transitions and metastable phases at compression (strain) rates of up to 500GPa/s (˜0.16s-1 for a metal). Our approach adapts electromechanical piezoelectric actuators to a conventional diamond anvil cell design, which enables precise specification and control of a time-dependent applied load/pressure. Existing DAC instrumentation and experimental techniques are easily adapted to the dDAC to measure the properties of a sample under the varying load/pressure conditions. This capability addresses the sparsely studied regime of dynamic phenomena between static research (diamond anvil cells and large volume presses) and dynamic shock-driven experiments (gas guns, explosive, and laser shock). We present an overview of a variety of experimental measurements that can be made with this device.

Standardized classroom management program: Social validation and replication studies in Utah and Oregon.

PubMed

Greenwood, C R; Hops, H; Walker, H M; Guild, J J; Stokes, J; Young, K R; Keleman, K S; Willardson, M

1979-01-01

A comprehensive validation study was conducted of the Program for Academic Survival Skills (PASS), a consultant-based, teacher-mediated program for student classroom behavior. The study addressed questions related to: (a) brief consultant training, (b) subsequent teacher training by consultants using PASS manuals, (c) contrasts between PASS experimental teachers and students and equivalent controls on measures of teacher management skills, student classroom behavior, teacher ratings of student problem behaviors, and academic achievement, (d) reported satisfaction of participants, and (e) replication of effects across two separate school sites. Results indicated that in both sites significant effects were noted in favor of the PASS experimental group for (a) teacher approval, (b) student appropriate classroom behavior, and (c) four categories of student inappropriate behavior. Program satisfaction ratings of students, teachers, and consultants were uniformly positive, and continued use of the program was reported a year later. Discussion focused upon issues of cost-effectiveness, differential site effects, and the relationship between appropriate classroom behavior and academic achievement.

Opportunities for Drell-Yan Physics at RHIC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aschenauer, E.; Bland, L.; Crawford, H.

Drell-Yan (DY) physics gives the unique opportunity to study the parton structure of nucleons in an experimentally and theoretically clean way. With the availability of polarized proton-proton collisions and asymmetric d+Au collisions at the Relativistic Heavy Ion Collider (RHIC), we have the basic (and unique in the world) tools to address several fundamental questions in QCD, including the expected gluon saturation at low partonic momenta and the universality of transverse momentum dependent parton distribution functions. A Drell-Yan program at RHIC is tied closely to the core physics questions of a possible future electron-ion collider, eRHIC. The more than 80 participantsmore » of this workshop focused on recent progress in these areas by both theory and experiment, trying to address imminent questions for the near and mid-term future.« less

Development, Testing, and Validation of a Model-Based Tool to Predict Operator Responses in Unexpected Workload Transitions

NASA Technical Reports Server (NTRS)

Sebok, Angelia; Wickens, Christopher; Sargent, Robert

2015-01-01

One human factors challenge is predicting operator performance in novel situations. Approaches such as drawing on relevant previous experience, and developing computational models to predict operator performance in complex situations, offer potential methods to address this challenge. A few concerns with modeling operator performance are that models need to realistic, and they need to be tested empirically and validated. In addition, many existing human performance modeling tools are complex and require that an analyst gain significant experience to be able to develop models for meaningful data collection. This paper describes an effort to address these challenges by developing an easy to use model-based tool, using models that were developed from a review of existing human performance literature and targeted experimental studies, and performing an empirical validation of key model predictions.

The Detection of Nonplanar Surfaces in Visual Space.

DTIC Science & Technology

1984-03-01

involve quasi -dotted stimuli. For example, applications may be found in fields such as air traffic control ; geophysical surveys (e.g., to distinguish a...line microcomputers. The control program was initially loaded by the experimenter from the computer’s disk O memory into its randomly addressable... experimenter and the computer carried out certain initialization segments of the control program. Next, the observer signed on at the computer terminal with a

Experimental Concepts for Testing Seismic Hazard Models

NASA Astrophysics Data System (ADS)

Marzocchi, W.; Jordan, T. H.

2015-12-01

Seismic hazard analysis is the primary interface through which useful information about earthquake rupture and wave propagation is delivered to society. To account for the randomness (aleatory variability) and limited knowledge (epistemic uncertainty) of these natural processes, seismologists must formulate and test hazard models using the concepts of probability. In this presentation, we will address the scientific objections that have been raised over the years against probabilistic seismic hazard analysis (PSHA). Owing to the paucity of observations, we must rely on expert opinion to quantify the epistemic uncertainties of PSHA models (e.g., in the weighting of individual models from logic-tree ensembles of plausible models). The main theoretical issue is a frequentist critique: subjectivity is immeasurable; ergo, PSHA models cannot be objectively tested against data; ergo, they are fundamentally unscientific. We have argued (PNAS, 111, 11973-11978) that the Bayesian subjectivity required for casting epistemic uncertainties can be bridged with the frequentist objectivity needed for pure significance testing through "experimental concepts." An experimental concept specifies collections of data, observed and not yet observed, that are judged to be exchangeable (i.e., with a joint distribution independent of the data ordering) when conditioned on a set of explanatory variables. We illustrate, through concrete examples, experimental concepts useful in the testing of PSHA models for ontological errors in the presence of aleatory variability and epistemic uncertainty. In particular, we describe experimental concepts that lead to exchangeable binary sequences that are statistically independent but not identically distributed, showing how the Bayesian concept of exchangeability generalizes the frequentist concept of experimental repeatability. We also address the issue of testing PSHA models using spatially correlated data.

The Utility of Geographical Information Systems (GIS) in Systems-Oriented Obesity Intervention Projects: The Selection of Comparable Study Sites for a Quasi-Experimental Intervention Design—TX CORD

PubMed Central

Byars, Allison; Byrd-Williams, Courtney; Sharma, Shreela V.; Durand, Casey; Hoelscher, Deanna M.; Butte, Nancy F.; Kelder, Steven H.

2015-01-01

Abstract Background: The Texas Childhood Obesity Research Demonstration project (TX CORD) uses a systems-oriented approach to address obesity that includes individual and family interventions, community-level action, as well as environmental and policy initiatives. Given that randomization is seldom possible in community-level intervention studies, TX CORD uses a quasi-experimental design. Comparable intervention and comparison study sites are needed to address internal validity bias. Methods: TX CORD was designed to be implemented in low-income, ethnically diverse communities in Austin and Houston, Texas. A three-stage Geographical Information System (GIS) methodology was used to establish and ascertain the comparability of the intervention and comparison study sites. Census tract (stage 1) and school (stage 2) data were used to identify spatially exclusive geographic areas that were comparable. In stage 3, study sites were compared on demographic characteristics, socioeconomic status (SES), food assets, and physical activity (PA) assets. Student's t-test was used to examine significant differences between the selected sites. Results: The methodology that was used resulted in the selection of catchment areas with demographic and socioeconomic characteristics that fit the target population: ethnically diverse population; lower-median household income; and lower home ownership rates. Additionally, the intervention and comparison sites were statistically comparable on demographic and SES variables, as well as food assets and PA assets. Conclusions: This GIS approach can provide researchers, program evaluators, and policy makers with useful tools for both research and practice. Area-level information that allows for robust understanding of communities can enhance analytical procedures in community health research and offer significant contributions in terms of community assessment and engagement. PMID:25587670

The utility of Geographical Information Systems (GIS) in systems-oriented obesity intervention projects: the selection of comparable study sites for a quasi-experimental intervention design--TX CORD.

PubMed

Oluyomi, Abiodun O; Byars, Allison; Byrd-Williams, Courtney; Sharma, Shreela V; Durand, Casey; Hoelscher, Deanna M; Butte, Nancy F; Kelder, Steven H

2015-02-01

The Texas Childhood Obesity Research Demonstration project (TX CORD) uses a systems-oriented approach to address obesity that includes individual and family interventions, community-level action, as well as environmental and policy initiatives. Given that randomization is seldom possible in community-level intervention studies, TX CORD uses a quasi-experimental design. Comparable intervention and comparison study sites are needed to address internal validity bias. TX CORD was designed to be implemented in low-income, ethnically diverse communities in Austin and Houston, Texas. A three-stage Geographical Information System (GIS) methodology was used to establish and ascertain the comparability of the intervention and comparison study sites. Census tract (stage 1) and school (stage 2) data were used to identify spatially exclusive geographic areas that were comparable. In stage 3, study sites were compared on demographic characteristics, socioeconomic status (SES), food assets, and physical activity (PA) assets. Student's t-test was used to examine significant differences between the selected sites. The methodology that was used resulted in the selection of catchment areas with demographic and socioeconomic characteristics that fit the target population: ethnically diverse population; lower-median household income; and lower home ownership rates. Additionally, the intervention and comparison sites were statistically comparable on demographic and SES variables, as well as food assets and PA assets. This GIS approach can provide researchers, program evaluators, and policy makers with useful tools for both research and practice. Area-level information that allows for robust understanding of communities can enhance analytical procedures in community health research and offer significant contributions in terms of community assessment and engagement.

Ovarian follicle maturation and ovulation: An integrated perspective

USGS Publications Warehouse

Patino, R.; Thomas, P.; Yoshizaki, G.

2003-01-01

Numerous studies with teleosts have addressed the regulation and mechanisms of oocyte maturation, but largely at the exclusion of ovulation. A smaller but still considerable number of studies have focused on ovulation, and ignored maturation. Consequently, little is known about the mechanistic linkages between these two events. New information is presented here indicating that luteinizing hormone regulates the acquisition not only of oocyte maturational competence, but also ovulatory competence. The thesis is presented that maturation and ovulation are closely integrated and overlapping events that are best viewed conceptually and experimentally as parts of a functional whole. ?? 2004 Kluwer Academic Publishers.

The acoustics of the violin: a review

NASA Astrophysics Data System (ADS)

Woodhouse, Jim

2014-11-01

To understand the design and function of the violin requires investigation of a range of scientific questions. This paper presents a review: the relevant physics covers the nonlinear vibration of a bowed string, the vibration of the instrument body, and the consequent sound radiation. Questions of discrimination and preference by listeners and players require additional studies using the techniques of experimental psychology, and these are also touched on in the paper. To address the concerns of players and makers of instruments requires study of the interaction of all these factors, coming together in the concept of ‘playability’ of an instrument.

Agent-based modeling and systems dynamics model reproduction.

DOE Office of Scientific and Technical Information (OSTI.GOV)

North, M. J.; Macal, C. M.

2009-01-01

Reproducibility is a pillar of the scientific endeavour. We view computer simulations as laboratories for electronic experimentation and therefore as tools for science. Recent studies have addressed model reproduction and found it to be surprisingly difficult to replicate published findings. There have been enough failed simulation replications to raise the question, 'can computer models be fully replicated?' This paper answers in the affirmative by reporting on a successful reproduction study using Mathematica, Repast and Swarm for the Beer Game supply chain model. The reproduction process was valuable because it demonstrated the original result's robustness across modelling methodologies and implementation environments.

Reproductive and developmental toxicity of the components of gasoline.

PubMed Central

Skalko, R G

1993-01-01

The reproductive, developmental, and postnatal toxicity of 14 select chemicals and mixtures that are components of gasoline has been reviewed. The majority of experimental analyses have been performed as either variations of the accepted segment 2 protocol or as traditional teratology studies. Specific deficiencies in the present database have been identified and are most obvious in the evaluation of reproductive and postnatal effects. It is recommended that future studies address the continuing need for assessment in multiple species and over a range of dosages with specific emphasis on the impact of route of administration on the results obtained. PMID:8020438

What we know and don't know about the bioeffects of nanoparticles: developing experimental approaches for safety assessment.

PubMed

Stratmeyer, Mel E; Goering, Peter L; Hitchins, Victoria M; Umbreit, Thomas H

2010-08-01

The Center for Devices and Radiological Health (CDRH) of the US Food and Drug Administration (FDA) regulates nano-based medical products and therefore is required to address the safety and biological effects of nano-scale materials used in these products. Both in vitro and in vivo toxicological research studies are being conducted at the FDA to help determine the risks versus benefits of these new products. This article will briefly summarize some of the initial research findings from FDA-CDRH studies using TiO(2), polystyrene, and silicon nanoparticles.

Comparative study of minutiae selection algorithms for ISO fingerprint templates

NASA Astrophysics Data System (ADS)

Vibert, B.; Charrier, C.; Le Bars, J.-M.; Rosenberger, C.

2015-03-01

We address the selection of fingerprint minutiae given a fingerprint ISO template. Minutiae selection plays a very important role when a secure element (i.e. a smart-card) is used. Because of the limited capability of computation and memory, the number of minutiae of a stored reference in the secure element is limited. We propose in this paper a comparative study of 6 minutiae selection methods including 2 methods from the literature and 1 like reference (No Selection). Experimental results on 3 fingerprint databases from the Fingerprint Verification Competition show their relative efficiency in terms of performance and computation time.

Zika Virus Infection in Pregnancy, Microcephaly, and Maternal and Fetal Health: What We Think, What We Know, and What We Think We Know.

PubMed

Alvarado, Maria Gabriela; Schwartz, David A

2017-01-01

-The global epidemic of Zika virus (ZIKV) infection has emerged as an important public health problem affecting pregnant women and their infants. -To review the causal association between ZIKV infection during pregnancy and intrauterine fetal infection, microcephaly, brain damage, congenital malformation syndrome, and experimental laboratory models of fetal infection. Many questions remain regarding the risk factors, pathophysiology, epidemiology, and timing of maternal-fetal transmission and disease. These include mechanisms of fetal brain damage and microcephaly; the role of covariables, such as viral burden, duration of viremia, and host genetics, on vertical transmission; and the clinical and pathologic spectrum of congenital Zika syndrome. Additional questions include defining the potential long-term physical and neurobehavioral outcomes for infected infants, whether maternal or fetal host genetics influence the clinical outcome, and whether ZIKV infection can cause maternal morbidity. Finally, are experimental laboratory and animal models of ZIKV infection helpful in addressing maternal-fetal viral transmission and the development of congenital microcephaly? This communication provides current information and attempts to address some of these important questions. -Comprehensive review of published scientific literature. -Recent advances in epidemiology, clinical medicine, pathology, and experimental studies have provided a great amount of new information regarding vertical ZIKV transmission and the mechanisms of congenital microcephaly, brain damage, and congenital Zika syndrome in a relatively short time. However, much work still needs to be performed to more completely understand the maternal and fetal aspects of this new and emerging viral disease.

Accelerated lattice Boltzmann model for colloidal suspensions rheology and interface morphology

NASA Astrophysics Data System (ADS)

Farhat, Hassan

Colloids are ubiquitous in the food, medical, cosmetic, polymer, water purification and pharmaceutical industries. Colloids thermal, mechanical and storage properties are highly dependent on their interface morphology and their rheological behavior. Numerical methods provide a cheap and reliable virtual laboratory for the study of colloids. However efficiency is a major concern to address when using numerical methods for practical applications. This work introduces the main building-blocks for an improved lattice Boltzmann-based numerical tool designed for the study of colloidal rheology and interface morphology. The efficiency of the proposed model is enhanced by using the recently developed and validated migrating multi-block algorithms for the lattice Boltzmann method (LBM). The migrating multi-block was used to simulate single component, multi-component, multiphase and single component multiphase flows. Results were validated by experimental, numerical and analytical solutions. The contamination of the fluid-fluid interface influences the colloids morphology. This issue was addressed by the introduction of the hybrid LBM for surfactant-covered droplets. The module was used for the simulation of surfactant-covered droplet deformation under shear and uniaxial extensional flows respectively and under buoyancy. Validation with experimental and theoretical results was provided. Colloids are non-Newtonian fluids which exhibit rich rheological behavior. The suppression of coalescence module is the part of the proposed model which facilitates the study of colloids rheology. The model results for the relative viscosity were in agreement with some theoretical results. Biological suspensions such as blood are macro-colloids by nature. The study of the blood flow in the microvasculature was heuristically approached by assuming the red blood cells as surfactant covered droplets. The effects of interfacial tension on the flow velocity and the droplet exclusion from the walls in parabolic flows were in qualitative agreement with some experimental and numerical results. The Fahraeus and the Fahraeus-Lindqvist effects were reproduced. The proposed LBM model provides a flexible numerical platform consisting of various modules which could be used separately or in combination for the study of a variety of colloids and biological suspensions flow deformation problems.

The Effects of STS Issue Investigation and Action Instruction Versus Traditional Life Science Instruction on Seventh Grade Students' Citizenship Behaviors

NASA Astrophysics Data System (ADS)

Wiesenmayer, Randall L.; Rubba, Peter A.

1999-06-01

The purpose of this study was to determine the effects of employing an STS instructional model that addresses each of the four goal levels of STS education versus an instructional model containing only life science content, on seventh grade students' participation in citizenship action on STS issues. A modified version of the non-equivalent control group quasi-experimental research design was used with seventeen intact seventh grade life science classes, ten of which received STS instruction ( N = 264) and seven of which received life science instruction ( N = 136) over 20 school days. The STS instruction sequentially addressed each of the four goal levels for STS education. Data were collected using the Actions Taken on Public Issues instrument to measure citizenship behaviors. ANOVA and repeated measures ANOVA were employed to analyze data. It was concluded from the findings that employment of an STS issue investigation with an action instructional model that addressed the four goal levels of STS education significantly increased seventh grade students' participation in citizenship actions on STS issues. Implications and recommendations are provided.

Summary of Research Adaptions of Visceral and Cerebral Resistance Arteries to Simulated Microgravity

NASA Technical Reports Server (NTRS)

Delp, Michael

2003-01-01

The proposed studies were designed address the effects of simulated microgravity on vascular smooth muscle and endothelial cell function in resistance arteries isolated from visceral tissues (spleen, mesentery and kidneys) and cerebrum. Alterations in vascular function induced by microgravity are particularly relevant to the problems of orthostatic intolerance and reduced exercise capacity experienced by astronauts upon re-entry into the earth's gravitational field. Decrements in contractile function or enhanced vasodilatory responsiveness of peripheral resistance arteries could lead to decreased peripheral resistance and orthostatic hypotension. Alternatively, augmentation of contractile function in cerebral resistance arteries could lead to increased cerebral vascular resistance and diminished perfusion of the brain. The Specific Aims and hypotheses were proposed in this grant. Following each of the Specific Aims, progress toward addressing that specific aim is presented. With the exception of Specific Aim VI (see aim for details), all aims have been experimentally addressed as proposed. The final six months of the granting period will be used for manuscript preparation; manuscripts in preparation will contain results from Specific Aims I-IV. Results from Specific Aims V and VI have been published.

Hormones in pain modulation and their clinical implications for pain control: a critical review.

PubMed

Chen, Xueyin; Zhang, Jinyuan; Wang, Xiangrui

2016-07-01

Recently, more and more studies have found that pain generation, transmission and modulation are under hormonal regulation. Indeed, hormonal dysregulation is a common component of chronic pain syndromes. Studies have attempted to determine whether the relationship between the pain and its perception and hormones is a causative relationship and how these processes interrelate. This review summarizes and analyzes the current experimental data and provides an overview of the studies addressing these questions. The relationship between pain perception and endocrine effects suggests that hormones can be used as important biomarkers of chronic pain syndromes and/or be developed into therapeutic agents in the fight against pain.

CXRO - The Center for X-ray Optics

Science.gov Websites

advanced experimental systems to address national needs, support research in material, life, and provides a stepping stone for realizing stable and highly scalable (10 nm and below) non-volatile memory

Aircraft turbofan noise

NASA Astrophysics Data System (ADS)

Groeneweg, J. F.; Rice, E. J.

1987-01-01

Turbofan noise generation and suppression in aircraft engines are reviewed. The chain of physical processes which connect unsteady flow interactions with fan blades to far field noise is addressed. Mechanism identification and description, duct propagation, radiation, and acoustic suppression are discussed. The experimental techniques of fan inflow static tests are discussed. Rotor blade surface pressure and wake velocity measurements aid in the determination of the types and strengths of the generation mechanisms. Approaches to predicting or measuring acoustic mode content, optimizing treatment impedance to maximize attenuation, translating impedance into porous wall structure, and interpreting far field directivity patterns are illustrated by comparisons of analytical and experimental results. The interdependence of source and acoustic treatment design to minimize far field noise is emphasized. Areas requiring further research are discussed, and the relevance of aircraft turbofan results to quieting other turbomachinery installation is addressed.

Aircraft turbofan noise

NASA Astrophysics Data System (ADS)

Groeneweg, J. F.; Rice, E. J.

1983-03-01

Turbofan noise generation and suppression in aircraft engines are reviewed. The chain of physical processes which connect unsteady flow interactions with fan blades to far field noise is addressed. Mechanism identification and description, duct propagation, radiation and acoustic suppression are discussed. The experimental technique of fan inflow static tests are discussed. Rotor blade surface pressure and wake velocity measurements aid in the determination of the types and strengths of the generation mechanisms. Approaches to predicting or measuring acoustic mode content, optimizing treatment impedance to maximize attenuation, translating impedance into porous wall structure and interpreting far field directivity patterns are illustrated by comparisons of analytical and experimental results. The interdependence of source and acoustic treatment design to minimize far field noise is emphasized. Area requiring further research are discussed and the relevance of aircraft turbofan results to quieting other turbomachinery installations is addressed.

Aircraft turbofan noise

NASA Technical Reports Server (NTRS)

Groeneweg, J. F.; Rice, E. J.

1983-01-01

Turbofan noise generation and suppression in aircraft engines are reviewed. The chain of physical processes which connect unsteady flow interactions with fan blades to far field noise is addressed. Mechanism identification and description, duct propagation, radiation and acoustic suppression are discussed. The experimental technique of fan inflow static tests are discussed. Rotor blade surface pressure and wake velocity measurements aid in the determination of the types and strengths of the generation mechanisms. Approaches to predicting or measuring acoustic mode content, optimizing treatment impedance to maximize attenuation, translating impedance into porous wall structure and interpreting far field directivity patterns are illustrated by comparisons of analytical and experimental results. The interdependence of source and acoustic treatment design to minimize far field noise is emphasized. Area requiring further research are discussed and the relevance of aircraft turbofan results to quieting other turbomachinery installations is addressed.

FUNGIBLE AND COMPATIBLE BIOFUELS: LITERATURE SEARCH, SUMMARY, AND RECOMMENDATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bunting, Bruce G; Bunce, Michael; Barone, Teresa L

2011-04-01

The purpose of the study described in this report is to summarize the various barriers to more widespread distribution of bio-fuels through our common carrier fuel distribution system, which includes pipelines, barges and rail, fuel tankage, and distribution terminals. Addressing these barriers is necessary to allow the more widespread utilization and distribution of bio-fuels, in support of a renewable fuels standard and possible future low-carbon fuel standards. These barriers can be classified into several categories, including operating practice, regulatory, technical, and acceptability barriers. Possible solutions to these issues are discussed; including compatibility evaluation, changes to bio-fuels, regulatory changes, and changesmore » in the distribution system or distribution practices. No actual experimental research has been conducted in the writing of this report, but results are used to develop recommendations for future research and additional study as appropriate. This project addresses recognized barriers to the wider use of bio-fuels in the areas of development of codes and standards, industrial and consumer awareness, and materials compatibility issues.« less

Spaceborne synthetic aperture radar: Current status and future directions. A report to the Committee on Earth Sciences, Space Studies Board, National Research Council

NASA Technical Reports Server (NTRS)

Evans, D. L. (Editor); Apel, J.; Arvidson, R.; Bindschadler, R.; Carsey, F.; Dozier, J.; Jezek, K.; Kasischke, E.; Li, F.; Melack, J.

1995-01-01

This report provides a context in which questions put forth by NASA's Office of Mission to Planet Earth (OMPTE) regarding the next steps in spaceborne synthetic aperture radar (SAR) science and technology can be addressed. It summarizes the state-of-the-art in theory, experimental design, technology, data analysis, and utilization of SAR data for studies of the Earth, and describes potential new applications. The report is divided into five science chapters and a technology assessment. The chapters summarize the value of existing SAR data and currently planned SAR systems, and identify gaps in observational capabilities needing to be filled to address the scientific questions. Cases where SAR provides complementary data to other (non-SAR) measurement techniques are also described. The chapter on technology assessment outlines SAR technology development which is critical not only to NASA's providing societally relevant geophysical parameters but to maintaining competitiveness in SAR technology, and promoting economic development.

Do Brief Alcohol Interventions Reduce Tobacco Use among Adolescents and Young Adults? A Systematic Review and Meta-Analysis

PubMed Central

Hennessy, Emily A.; Tanner-Smith, Emily E.; Steinka-Fry, Katarzyna T.

2015-01-01

This meta-analysis synthesizes studies of brief interventions (BIs) that targeted alcohol consumption and reported both alcohol and tobacco outcomes. It examines whether BIs reduce alcohol and tobacco use for adolescents and young adults among interventions that (1) directly targeted tobacco and alcohol use, or (2) did not target tobacco use but measured it as a secondary outcome. Multiple databases and grey literature sources were searched (1980–2012) resulting in the identification of 18 randomized or controlled quasi-experimental studies (5949 participants). Analyses were conducted using random effects inverse-variance weighted three-level models. BIs were associated with a significant reduction in alcohol consumption relative to control groups (ḡ = 0.11, 95% CI [0.04, 0.17]) but not with a significant decrease in tobacco use (ḡ = 0.07, 95% CI [−0.01, 0.16]). Directly addressing tobacco was not a significant moderator affecting tobacco use outcomes. Post-hoc exploratory analysis revealed potential questions to address with future research. PMID:26130030

Experimental Evaluation of Fuzzy Logic Control of a Flexible Arm Manipulator

DTIC Science & Technology

1993-12-09

temperature into a fuzzy context), and humidity is musty, Then air conditioner power is high. The database and knowledge base combine to form the...this case, the output, perhaps air conditioner power, would be medium to a degree of 50%. However, as shown in Table 3.2, Oare are more possible...OF WASHINGTON AFIT/CI/CIA-93-167 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING DEPARTMENI OF THE AIR FORCE AGENCY

Postbuckling failure of composite plates with central holes. Interim Report, Feb. 1990 - Dec. 1991 Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Lee, H. H.; Hyer, M. W.

1992-01-01

The postbuckling failure of square composite plates with central holes is analyzed numerically and experimentally. The particular plates studies have stacking sequences of: (+ and - 45/0/90)(sub 2S); (+ and - 45/0(sub 2))(sub 2S); (+ and - 45/0(sub 6))(sub S); and (+ and - 45)(sub 4S). A simple plate geometry, one with a hole diameter to plate width ratio of 0.3 is compared. Failure load, failure mode, and failure location are predicted numerically by using the finite element method. Predictions are compared with experimental results. In numerical failure analysis the interlaminar shear stresses, as well as the inplane stresses are taken into account. An issue addressed in this study is the possible mode shape change of the plate during loading. It is predicted that the first three laminates fail due to excessive stresses in the fiber direction, and more importantly, that the load level is independent of whether the laminate is deformed in a one-half or two-half wave configuration. It is predicted that the fourth laminate fails due to excessive inplane shear stress. Interlaminar shear failure is not predicted for any laminates. For the first two laminates the experimental observations correlated well with the predictions. Experimentally, the third laminate failed along the side support due to interlaminar shear strength S(sub 23). The fourth experimental laminate failed due to inplane shear in the location predicted, however material softening resulted in a different failure load from predictions.

Factorial Experiments: Efficient Tools for Evaluation of Intervention Components

PubMed Central

Collins, Linda M.; Dziak, John J.; Kugler, Kari C.; Trail, Jessica B.

2014-01-01

Background An understanding of the individual and combined effects of a set of intervention components is important for moving the science of preventive medicine interventions forward. This understanding can often be achieved in an efficient and economical way via a factorial experiment, in which two or more independent variables are manipulated. The factorial experiment is a complement to the randomized controlled trial (RCT); the two designs address different research questions. Purpose This article offers an introduction to factorial experiments aimed at investigators trained primarily in the RCT. Method The factorial experiment is compared and contrasted with other experimental designs used commonly in intervention science to highlight where each is most efficient and appropriate. Results Several points are made: factorial experiments make very efficient use of experimental subjects when the data are properly analyzed; a factorial experiment can have excellent statistical power even if it has relatively few subjects per experimental condition; and when conducting research to select components for inclusion in a multicomponent intervention, interactions should be studied rather than avoided. Conclusions Investigators in preventive medicine and related areas should begin considering factorial experiments alongside other approaches. Experimental designs should be chosen from a resource management perspective, which states that the best experimental design is the one that provides the greatest scientific benefit without exceeding available resources. PMID:25092122

Behavioral Assessment of Listening Effort Using a Dual-Task Paradigm.

PubMed

Gagné, Jean-Pierre; Besser, Jana; Lemke, Ulrike

2017-01-01

Published investigations ( n = 29) in which a dual-task experimental paradigm was employed to measure listening effort during speech understanding in younger and older adults were reviewed. A summary of the main findings reported in the articles is provided with respect to the participants' age-group and hearing status. Effects of different signal characteristics, such as the test modality, on dual-task outcomes are evaluated, and associations with cognitive abilities and self-report measures of listening effort are described. Then, several procedural issues associated with the use of dual-task experiment paradigms are discussed. Finally, some issues that warrant future research are addressed. The review revealed large variability in the dual-task experimental paradigms that have been used to measure the listening effort expended during speech understanding. The differences in experimental procedures used across studies make it difficult to draw firm conclusions concerning the optimal choice of dual-task paradigm or the sensitivity of specific paradigms to different types of experimental manipulations. In general, the analysis confirmed that dual-task paradigms have been used successfully to measure differences in effort under different experimental conditions, in both younger and older adults. Several research questions that warrant further investigation in order to better understand and characterize the intricacies of dual-task paradigms were identified.

Behavioral Assessment of Listening Effort Using a Dual-Task Paradigm

PubMed Central

Besser, Jana; Lemke, Ulrike

2017-01-01

Published investigations (n = 29) in which a dual-task experimental paradigm was employed to measure listening effort during speech understanding in younger and older adults were reviewed. A summary of the main findings reported in the articles is provided with respect to the participants’ age-group and hearing status. Effects of different signal characteristics, such as the test modality, on dual-task outcomes are evaluated, and associations with cognitive abilities and self-report measures of listening effort are described. Then, several procedural issues associated with the use of dual-task experiment paradigms are discussed. Finally, some issues that warrant future research are addressed. The review revealed large variability in the dual-task experimental paradigms that have been used to measure the listening effort expended during speech understanding. The differences in experimental procedures used across studies make it difficult to draw firm conclusions concerning the optimal choice of dual-task paradigm or the sensitivity of specific paradigms to different types of experimental manipulations. In general, the analysis confirmed that dual-task paradigms have been used successfully to measure differences in effort under different experimental conditions, in both younger and older adults. Several research questions that warrant further investigation in order to better understand and characterize the intricacies of dual-task paradigms were identified. PMID:28091178

Systematic survey of the design, statistical analysis, and reporting of studies published in the 2008 volume of the Journal of Cerebral Blood Flow and Metabolism.

PubMed

Vesterinen, Hanna M; Vesterinen, Hanna V; Egan, Kieren; Deister, Amelie; Schlattmann, Peter; Macleod, Malcolm R; Dirnagl, Ulrich

2011-04-01

Translating experimental findings into clinically effective therapies is one of the major bottlenecks of modern medicine. As this has been particularly true for cerebrovascular research, attention has turned to the quality and validity of experimental cerebrovascular studies. We set out to assess the study design, statistical analyses, and reporting of cerebrovascular research. We assessed all original articles published in the Journal of Cerebral Blood Flow and Metabolism during the year 2008 against a checklist designed to capture the key attributes relating to study design, statistical analyses, and reporting. A total of 156 original publications were included (animal, in vitro, human). Few studies reported a primary research hypothesis, statement of purpose, or measures to safeguard internal validity (such as randomization, blinding, exclusion or inclusion criteria). Many studies lacked sufficient information regarding methods and results to form a reasonable judgment about their validity. In nearly 20% of studies, statistical tests were either not appropriate or information to allow assessment of appropriateness was lacking. This study identifies a number of factors that should be addressed if the quality of research in basic and translational biomedicine is to be improved. We support the widespread implementation of the ARRIVE (Animal Research Reporting In Vivo Experiments) statement for the reporting of experimental studies in biomedicine, for improving training in proper study design and analysis, and that reviewers and editors adopt a more constructively critical approach in the assessment of manuscripts for publication.

Systematic survey of the design, statistical analysis, and reporting of studies published in the 2008 volume of the Journal of Cerebral Blood Flow and Metabolism

PubMed Central

Vesterinen, Hanna V; Egan, Kieren; Deister, Amelie; Schlattmann, Peter; Macleod, Malcolm R; Dirnagl, Ulrich

2011-01-01

Translating experimental findings into clinically effective therapies is one of the major bottlenecks of modern medicine. As this has been particularly true for cerebrovascular research, attention has turned to the quality and validity of experimental cerebrovascular studies. We set out to assess the study design, statistical analyses, and reporting of cerebrovascular research. We assessed all original articles published in the Journal of Cerebral Blood Flow and Metabolism during the year 2008 against a checklist designed to capture the key attributes relating to study design, statistical analyses, and reporting. A total of 156 original publications were included (animal, in vitro, human). Few studies reported a primary research hypothesis, statement of purpose, or measures to safeguard internal validity (such as randomization, blinding, exclusion or inclusion criteria). Many studies lacked sufficient information regarding methods and results to form a reasonable judgment about their validity. In nearly 20% of studies, statistical tests were either not appropriate or information to allow assessment of appropriateness was lacking. This study identifies a number of factors that should be addressed if the quality of research in basic and translational biomedicine is to be improved. We support the widespread implementation of the ARRIVE (Animal Research Reporting In Vivo Experiments) statement for the reporting of experimental studies in biomedicine, for improving training in proper study design and analysis, and that reviewers and editors adopt a more constructively critical approach in the assessment of manuscripts for publication. PMID:21157472

Couple-based treatment for sexual problems following breast cancer: A review and synthesis of the literature.

PubMed

Carroll, Allison J; Baron, Shirley R; Carroll, Richard A

2016-08-01

Although there are many physical and psychological impacts on women's sexuality following breast cancer diagnosis and treatment, sexual problems often remain unaddressed in these cancer survivors. Given the crucial role of the partner in sexual issues, couple-based sex therapy would appear to be a logical first-line treatment for this population, but there is scant research on the efficacy of couple-based treatments and/or sex therapy in breast cancer survivors. A review of the literature was conducted using the PMC, PsycINFO, EMBASE, and MEDLINE databases. Articles were included that presented the results of an experimental or quasi-experimental clinical trial evaluating a psychosexual intervention for couples, targeted women diagnosed with breast cancer and their partners, and included outcome measures of sexual function and sexuality. Studies were excluded if the primary intervention was not focused on sexual problems or if they were published in a language other than English. From 2231 records, five articles met criteria for inclusion in the present review. Couple-based sex therapy appears to be an effective and highly accepted treatment for addressing sexual problems in breast cancer patients. These interventions were associated with improvements in sexual physiology, sexual functioning, sexual self-image, and sexual relationships, as well as improved psychological well-being of both breast cancer patients and their partners. Based on this review, the authors address clinical implications, particularly incorporating psychological treatment for sexual problems in comprehensive cancer care, and provide recommendations for further study.

Psychological and Neural Mechanisms of Experimental Extinction: A Selective Review

PubMed Central

Delamater, Andrew R.; Westbrook, R. Frederick

2013-01-01

The present review examines key psychological concepts in the study of experimental extinction and implications these have for an understanding of the underlying neurobiology of extinction learning. We suggest that many of the signature characteristics of extinction learning (spontaneous recovery, renewal, reinstatement, rapid reacquisition) can be accommodated by the standard associative learning theory assumption that extinction results in partial erasure of the original learning together with new inhibitory learning. Moreover, we consider recent behavioral and neural evidence that supports the partial erasure view of extinction, but also note shortcomings in our understanding of extinction circuits as these relate to the negative prediction error concept. Recent work suggests that common prediction error and stimulus-specific prediction error terms both may be required to explain neural plasticity both in acquisition and extinction learning. In addition, we suggest that many issues in the content of extinction learning have not been fully addressed in current research, but that neurobiological approaches should be especially helpful in addressing such issues. These include questions about the nature of extinction learning (excitatory CS-No US, inhibitory CS-US learning, occasion setting processes), especially as this relates to studies of the micro-circuitry of extinction, as well as its representational content (sensory, motivational, response). An additional understudied problem in extinction research is the role played by attention processes and their underlying neural networks, although some research and theory converge on the idea that extinction is accompanied by attention decrements (i.e., habituation-like processes). PMID:24104049

Psychological and neural mechanisms of experimental extinction: a selective review.

PubMed

Delamater, Andrew R; Westbrook, R Frederick

2014-02-01

The present review examines key psychological concepts in the study of experimental extinction and implications these have for an understanding of the underlying neurobiology of extinction learning. We suggest that many of the signature characteristics of extinction learning (spontaneous recovery, renewal, reinstatement, rapid reacquisition) can be accommodated by the standard associative learning theory assumption that extinction results in partial erasure of the original learning together with new inhibitory learning. Moreover, we consider recent behavioral and neural evidence that supports the partial erasure view of extinction, but also note shortcomings in our understanding of extinction circuits as these relate to the negative prediction error concept. Recent work suggests that common prediction error and stimulus-specific prediction error terms both may be required to explain neural plasticity both in acquisition and extinction learning. In addition, we suggest that many issues in the content of extinction learning have not been fully addressed in current research, but that neurobiological approaches should be especially helpful in addressing such issues. These include questions about the nature of extinction learning (excitatory CS-No US, inhibitory CS-US learning, occasion setting processes), especially as this relates to studies of the micro-circuitry of extinction, as well as its representational content (sensory, motivational, response). An additional understudied problem in extinction research is the role played by attention processes and their underlying neural networks, although some research and theory converge on the idea that extinction is accompanied by attention decrements (i.e., habituation-like processes). Copyright © 2013 Elsevier Inc. All rights reserved.

Technical Evaluation Report, Part A - Vortex Flow and High Angle of Attack

NASA Technical Reports Server (NTRS)

Luckring, James M.

2003-01-01

A symposium entitled Vortex Flow and High Angle of Attack was held in Loen, Norway, from May 7 through May 11, 2001. The Applied Vehicle Technology (AVT) panel, under the auspices of the Research and Technology Organization (RTO), sponsored this symposium. Forty-eight papers, organized into nine sessions, addressed computational and experimental studies of vortex flows pertinent to both aircraft and maritime applications. The studies also ranged from fundamental fluids investigations to flight test results, and significant results were contributed from a broad range of countries. The principal emphasis of this symposium was on "the understanding and prediction of separation-induced vortex flows and their effects on military vehicle performance, stability, control, and structural design loads." It was further observed by the program committee that "separation- induced vortex flows are an important part of the design and off-design performance of conventional fighter aircraft and new conventional or unconventional manned or unmanned advanced vehicle designs (UAVs, manned aircraft, missiles, space planes, ground-based vehicles, and ships)." The nine sessions addressed the following topics: vortical flows on wings and bodies, experimental techniques for vortical flows, numerical simulations of vortical flows, vortex stability and breakdown, vortex flows in maritime applications, vortex interactions and control, vortex dynamics, flight testing, and vehicle design. The purpose of this paper is to provide brief reviews of these papers along with some synthesizing perspectives toward future vortex flow research opportunities. The paper includes the symposium program. (15 refs.)

Analytical one-dimensional model for laser-induced ultrasound in planar optically absorbing layer.

PubMed

Svanström, Erika; Linder, Tomas; Löfqvist, Torbjörn

2014-03-01

Ultrasound generated by means of laser-based photoacoustic principles are in common use today and applications can be found both in biomedical diagnostics, non-destructive testing and materials characterisation. For certain measurement applications it could be beneficial to shape the generated ultrasound regarding spectral properties and temporal profile. To address this, we studied the generation and propagation of laser-induced ultrasound in a planar, layered structure. We derived an analytical expression for the induced pressure wave, including different physical and optical properties of each layer. A Laplace transform approach was employed in analytically solving the resulting set of photoacoustic wave equations. The results correspond to simulations and were compared to experimental results. To enable the comparison between recorded voltage from the experiments and the calculated pressure we employed a system identification procedure based on physical properties of the ultrasonic transducer to convert the calculated acoustic pressure to voltages. We found reasonable agreement between experimentally obtained voltages and the voltages determined from the calculated acoustic pressure, for the samples studied. The system identification procedure was found to be unstable, however, possibly from violations of material isotropy assumptions by film adhesives and coatings in the experiment. The presented analytical model can serve as a basis when addressing the inverse problem of shaping an acoustic pulse from absorption of a laser pulse in a planar layered structure of elastic materials. Copyright © 2013 Elsevier B.V. All rights reserved.

Stem cell therapy for cardiovascular disease: the demise of alchemy and rise of pharmacology

PubMed Central

Jadczyk, T; Faulkner, A; Madeddu, P

2013-01-01

Regenerative medicine holds great promise as a way of addressing the limitations of current treatments of ischaemic disease. In preclinical models, transplantation of different types of stem cells or progenitor cells results in improved recovery from ischaemia. Furthermore, experimental studies indicate that cell therapy influences a spectrum of processes, including neovascularization and cardiomyogenesis as well as inflammation, apoptosis and interstitial fibrosis. Thus, distinct strategies might be required for specific regenerative needs. Nonetheless, clinical studies have so far investigated a relatively small number of options, focusing mainly on the use of bone marrow-derived cells. Rapid clinical translation resulted in a number of small clinical trials that do not have sufficient power to address the therapeutic potential of the new approach. Moreover, full exploitation has been hindered so far by the absence of a solid theoretical framework and inadequate development plans. This article reviews the current knowledge on cell therapy and proposes a model theory for interpretation of experimental and clinical outcomes from a pharmacological perspective. Eventually, with an increased association between cell therapy and traditional pharmacotherapy, we will soon need to adopt a unified theory for understanding how the two practices additively interact for a patient's benefit. LINKED ARTICLES This article is part of a themed section on Regenerative Medicine and Pharmacology: A Look to the Future. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2013.169.issue-2 PMID:22712727

Mycotoxins co-contamination: Methodological aspects and biological relevance of combined toxicity studies.

PubMed

Alassane-Kpembi, Imourana; Schatzmayr, Gerd; Taranu, Ionelia; Marin, Daniela; Puel, Olivier; Oswald, Isabelle Paule

2017-11-02

Mycotoxins are secondary fungal metabolites produced mainly by Aspergillus, Penicillium, and Fusarium. As evidenced by large-scale surveys, humans and animals are simultaneously exposed to several mycotoxins. Simultaneous exposure could result in synergistic, additive or antagonistic effects. However, most toxicity studies addressed the effects of mycotoxins separately. We present the experimental designs and we discuss the conclusions drawn from in vitro experiments exploring toxicological interactions of mycotoxins. We report more than 80 publications related to mycotoxin interactions. The studies explored combinations involving the regulated groups of mycotoxins, especially aflatoxins, ochratoxins, fumonisins, zearalenone and trichothecenes, but also the "emerging" mycotoxins beauvericin and enniatins. Over 50 publications are based on the arithmetic model of additivity. Few studies used the factorial designs or the theoretical biology-based models of additivity. The latter approaches are gaining increased attention. These analyses allow determination of the type of interaction and, optionally, its magnitude. The type of interaction reported for mycotoxin combinations depended on several factors, in particular cell models and the tested dose ranges. However, synergy among Fusarium toxins was highlighted in several studies. This review indicates that well-addressed in vitro studies remain valuable tools for the screening of interactive potential in mycotoxin mixtures.

Space Gerontology

NASA Technical Reports Server (NTRS)

Miquel, J. (Editor); Economos, A. C. (Editor)

1982-01-01

Presentations are given which address the effects of space flght on the older person, the parallels between the physiological responses to weightlessness and the aging process, and experimental possibilities afforded by the weightless environment to fundamental research in gerontology and geriatrics.

The integrated manual and automatic control of complex flight systems

NASA Technical Reports Server (NTRS)

Schmidt, D. K.

1984-01-01

A unified control synthesis methodology for complex and/or non-conventional flight vehicles are developed. Prediction techniques for the handling characteristics of such vehicles and pilot parameter identification from experimental data are addressed.

Understanding the Role of Conscientiousness in Healthy Aging: Where Does the Brain Come In?

PubMed Central

Patrick, Christopher J.

2014-01-01

In reviewing this impressive series of articles, I was struck by two points in particular: (1) the fact that the empirically-oriented articles focused on analyses of data from very large samples, with the two papers by Friedman and colleagues highlighting an approach to merging existing datasets through use of “metric bridges” in order to address key questions not addressable through one dataset alone, and (2) the fact that the articles as a whole included limited mention of neuroscientific (i.e., brain research) concepts, methods, and findings. One likely reason for the lack of reference to brain-oriented work is the persisting gap between smaller-N lab-experimental and larger-N multivariate-correlational approaches to psychological research. As a strategy for addressing this gap and bringing a distinct neuroscientific component to the National Institute on Aging’s conscientiousness and health initiative, I suggest that the metric bridging approach highlighted by Friedman and colleagues could be used to connect existing large-scale datasets containing both neurophysiological variables and measures of individual difference constructs to other datasets containing richer arrays of non-physiological variables—including data from longitudinal or twin studies focusing on personality and health-related outcomes (e.g., Terman Life Cycle study and Hawaii longitudinal studies, as described in the article by Kern et al.). PMID:24773108

An experimental investigation on orthogonal cutting of hybrid CFRP/Ti stacks

NASA Astrophysics Data System (ADS)

Xu, Jinyang; El Mansori, Mohamed

2016-10-01

Hybrid CFRP/Ti stack has been widely used in the modern aerospace industry owing to its superior mechanical/physical properties and excellent structural functions. Several applications require mechanical machining of these hybrid composite stacks in order to achieve dimensional accuracy and assembly performance. However, machining of such composite-to-metal alliance is usually an extremely challenging task in the manufacturing sectors due to the disparate natures of each stacked constituent and their respective poor machinability. Special issues may arise from the high force/heat generation, severe subsurface damage and rapid tool wear. To study the fundamental mechanisms controlling the bi-material machining, this paper presented an experimental study on orthogonal cutting of hybrid CFRP/Ti stack by using superior polycrystalline diamond (PCD) tipped tools. The utilized cutting parameters for hybrid CFRP/Ti machining were rigorously adopted through a compromise selection due to the disparate machinability behaviors of the CFRP laminate and Ti alloy. The key cutting responses in terms of cutting force generation, machined surface quality and tool wear mechanism were precisely addressed. The experimental results highlighted the involved five stages of CFRP/Ti cutting and the predominant crater wear and edge fracture failure governing the PCD cutting process.

The validation of a generalized Hooke's law for coronary arteries.

PubMed

Wang, Chong; Zhang, Wei; Kassab, Ghassan S

2008-01-01

The exponential form of constitutive model is widely used in biomechanical studies of blood vessels. There are two main issues, however, with this model: 1) the curve fits of experimental data are not always satisfactory, and 2) the material parameters may be oversensitive. A new type of strain measure in a generalized Hooke's law for blood vessels was recently proposed by our group to address these issues. The new model has one nonlinear parameter and six linear parameters. In this study, the stress-strain equation is validated by fitting the model to experimental data of porcine coronary arteries. Material constants of left anterior descending artery and right coronary artery for the Hooke's law were computed with a separable nonlinear least-squares method with an excellent goodness of fit. A parameter sensitivity analysis shows that the stability of material constants is improved compared with the exponential model and a biphasic model. A boundary value problem was solved to demonstrate that the model prediction can match the measured arterial deformation under experimental loading conditions. The validated constitutive relation will serve as a basis for the solution of various boundary value problems of cardiovascular biomechanics.

A Computational Study on the Ground and Excited States of Nickel Silicide.

PubMed

Schoendorff, George; Morris, Alexis R; Hu, Emily D; Wilson, Angela K

2015-09-17

Nickel silicide has been studied with a range of computational methods to determine the nature of the Ni-Si bond. Additionally, the physical effects that need to be addressed within calculations to predict the equilibrium bond length and bond dissociation energy within experimental error have been determined. The ground state is predicted to be a (1)Σ(+) state with a bond order of 2.41 corresponding to a triple bond with weak π bonds. It is shown that calculation of the ground state equilibrium geometry requires a polarized basis set and treatment of dynamic correlation including up to triple excitations with CR-CCSD(T)L resulting in an equilibrium bond length of only 0.012 Å shorter than the experimental bond length. Previous calculations of the bond dissociation energy resulted in energies that were only 34.8% to 76.5% of the experimental bond dissociation energy. It is shown here that use of polarized basis sets, treatment of triple excitations, correlation of the valence and subvalence electrons, and a Λ coupled cluster approach is required to obtain a bond dissociation energy that deviates as little as 1% from experiment.

The use of clinical trials in comparative effectiveness research on mental health

PubMed Central

Blanco, Carlos; Rafful, Claudia; Olfson, Mark

2013-01-01

Objectives A large body of research on comparative effectiveness research (CER) focuses on the use of observational and quasi-experimental approaches. We sought to examine the use of clinical trials as a tool for CER, particularly in mental health. Study Design and Setting Examination of three ongoing randomized clinical trials in psychiatry that address issues which would pose difficulties for non-experimental CER methods. Results Existing statistical approaches to non-experimental data appear insufficient to compensate for biases that may arise when the pattern of missing data cannot be properly modeled such as when there are no standards for treatment, when affected populations have limited access to treatment, or when there are high rates of treatment dropout. Conclusions Clinical trials should retain an important role in CER, particularly in cases of high disorder prevalence, large expected effect sizes, difficult to reach populations or when examining sequential treatments or stepped-care algorithms. Progress in CER in mental health will require careful consideration of appropriate selection between clinical trials and non-experimental designs and on allocation of research resources to optimally inform key treatment decisions for each individual patient. PMID:23849150

Comprehensive Study On The Metastable Negative Ion Fragmentation Of Individual Dna Components And Larger Oligonucleotides

NASA Astrophysics Data System (ADS)

Ingolfsson, O.; Flosadottir, H. D.; Omarsson, B.; Ilko, B.

2010-07-01

Here we present a systematic study on the unimolecular decay pathways of the deprotonated building blocks of DNA and RNA to address the following questions: 1. Are the negative ion fragmentation patterns observed in the metastable decay of individual DNA components still evident when these are combined to larger oligonucleotides? 2. What is the significance of the charge location in determining the fragmentation pathways in the metastable decay process? 3. Are those metastable decay channels relevant in dissociative electron attachment to DNA components? To address these questions we have studied the fragmentation patterns of the deprotonated ribose and ribose 5'-monophosphate, the fragmentation patterns of the individual bases, all nucleosides and all 2'-deoxynucleosides as well as the individual nucleotides and several combinations of hexameric oligonucleotides. Furthermore, to understand the significance of the charge location in determining the fragmentation path in the metastable decay process of these deprotonated ions we have also studied modified uridine and guanosine. These have been modified to block different deprotonation sites and thus to control the initial step in the in the fragmentation process i.e. the site of deprotonation. In addition to our experimental approach we have also simulated the metastable fragmentation of the deprotonated uridine and 2'-deoxyguanosine to clarify the mechanisms and fragmentation patterns observed. Where data is available, the results are compared to dissociative electron attachment to DNA components and discussed in context to the underlying mechanism. Experiments on modified nucleosides where selected deprotonation sites have been blocked are used to verify the predicted reaction paths and imulations on uridine and 2'-deoxyguanosine are compared to the experimental results and used to shed light on the mechanisms involved.

SAW based micro- and acousto-fluidics in biomedicine

NASA Astrophysics Data System (ADS)

Ramasamy, Mouli; Varadan, Vijay K.

2017-04-01

Protein association starts with random collisions of individual proteins. Multiple collisions and rotational diffusion brings the molecules to a state of orientation. Majority of the protein associations are influenced by electrostatic interactions. To introduce: electrostatic rate enhancement, Brownian dynamics and transient complex theory has been traditionally used. Due to the recent advances in interdisciplinary sciences, an array of molecular assembly methods is being studied. Protein nanostructural assembly and macromolecular crowding are derived from the subsets of biochemistry to study protein-protein interactions and protein self-assembly. This paper tries to investigate the issue of enhancing the protein self-association rate, and bridging the gap between the simulations and experimental results. The methods proposed here include: electrostatic rate enhancement, macromolecular crowing, nanostructural protein assembly, microfluidics based approaches and magnetic force based approaches. Despite the suggestions of several methods, microfluidic and magnetic force based approaches seem to serve the need of protein assembly in a wider scale. Congruence of these approaches may also yield better results. Even though, these methods prove to be conceptually strong, to prevent the disagreement of theory and practice, a wide range of experiments is required. This proposal intends to study theoretical and experimental methods to successfully implement the aforementioned assembly strategies, and conclude with an extensive analysis of experimental data to address practical feasibility.

Global assessment of experimental climate warming on tundra vegetation: heterogeneity over space and time.

PubMed

Elmendorf, Sarah C; Henry, Gregory H R; Hollister, Robert D; Björk, Robert G; Bjorkman, Anne D; Callaghan, Terry V; Collier, Laura Siegwart; Cooper, Elisabeth J; Cornelissen, Johannes H C; Day, Thomas A; Fosaa, Anna Maria; Gould, William A; Grétarsdóttir, Járngerður; Harte, John; Hermanutz, Luise; Hik, David S; Hofgaard, Annika; Jarrad, Frith; Jónsdóttir, Ingibjörg Svala; Keuper, Frida; Klanderud, Kari; Klein, Julia A; Koh, Saewan; Kudo, Gaku; Lang, Simone I; Loewen, Val; May, Jeremy L; Mercado, Joel; Michelsen, Anders; Molau, Ulf; Myers-Smith, Isla H; Oberbauer, Steven F; Pieper, Sara; Post, Eric; Rixen, Christian; Robinson, Clare H; Schmidt, Niels Martin; Shaver, Gaius R; Stenström, Anna; Tolvanen, Anne; Totland, Orjan; Troxler, Tiffany; Wahren, Carl-Henrik; Webber, Patrick J; Welker, Jeffery M; Wookey, Philip A

2012-02-01

Understanding the sensitivity of tundra vegetation to climate warming is critical to forecasting future biodiversity and vegetation feedbacks to climate. In situ warming experiments accelerate climate change on a small scale to forecast responses of local plant communities. Limitations of this approach include the apparent site-specificity of results and uncertainty about the power of short-term studies to anticipate longer term change. We address these issues with a synthesis of 61 experimental warming studies, of up to 20 years duration, in tundra sites worldwide. The response of plant groups to warming often differed with ambient summer temperature, soil moisture and experimental duration. Shrubs increased with warming only where ambient temperature was high, whereas graminoids increased primarily in the coldest study sites. Linear increases in effect size over time were frequently observed. There was little indication of saturating or accelerating effects, as would be predicted if negative or positive vegetation feedbacks were common. These results indicate that tundra vegetation exhibits strong regional variation in response to warming, and that in vulnerable regions, cumulative effects of long-term warming on tundra vegetation - and associated ecosystem consequences - have the potential to be much greater than we have observed to date. © 2011 Blackwell Publishing Ltd/CNRS.

Stigmatization of obese individuals by human resource professionals: an experimental study.

PubMed

Giel, Katrin E; Zipfel, Stephan; Alizadeh, Manuela; Schäffeler, Norbert; Zahn, Carmen; Wessel, Daniel; Hesse, Friedrich W; Thiel, Syra; Thiel, Ansgar

2012-07-16

Weight-related stigmatization is a public health problem. It impairs the psychological well-being of obese individuals and hinders them from adopting weight-loss behaviors. We conducted an experimental study to investigate weight stigmatization in work settings using a sample of experienced human resource (HR) professionals from a real-life employment setting. In a cross-sectional, computer-based experimental study, a volunteer sample of 127 HR professionals (age: 41.1 ± 10.9 yrs., 56% female), who regularly make career decisions about other people, evaluated individuals shown in standardized photographs regarding work-related prestige and achievements. The photographed individuals differed with respect to gender, ethnicity, and Body Mass Index (BMI). Participants underestimated the occupational prestige of obese individuals and overestimated it for normal-weight individuals. Obese people were more often disqualified from being hired and less often nominated for a supervisory position, while non-ethnic normal-weight individuals were favored. Stigmatization was most pronounced in obese females. The data suggest that HR professionals are prone to pronounced weight stigmatization, especially in women. This highlights the need for interventions targeting this stigmatization as well as stigma-management strategies for obese individuals. Weight stigmatization and its consequences needs to be a topic that is more strongly addressed in clinical obesity care.

Use of electronic cigarettes among Romanian university students: a cross-sectional study.

PubMed

Lotrean, Lucia Maria

2015-04-11

Because electronic cigarettes are relatively new, data on usage patterns and factors which influence them are sparse. Hence, this study aims at assessing awareness, beliefs about electronic cigarettes and experimentation with them among university students from Romania- a country where the sales and marketing of these products are widespread. Secondly, correlates of electronic cigarette experimentation will also be investigated. A cross-sectional study was performed by means of anonymous questionnaires among 480 students, aged 19-24, from Cluj-Napoca, Romania, between April-May 2013. The results show that 92.5% of the students have heard about e-cigarettes; out of these, one quarter (53.3% of the smokers, 25% of the ex-smokers, 5.5% of the non-smokers) have tried electronic cigarettes at least once during lifetime. The results of the multinomial logistic regression point out that the correlates of electronic cigarette experimentation were: male gender, being a smoker of traditional cigarettes, having friends who experimented with electronic cigarettes, having stronger beliefs that electronic cigarettes could help them quit smoking and being less convinced that they are used only by smokers. The explained variance was 59%. The results underline the importance of addressing the issue of e-cigarette use through health education programs and regulatory interventions, since e-cigarettes are a reality faced by the Romanian youth.

Consideration of the Aluminum Distribution in Zeolites in Theoretical and Experimental Catalysis Research

DOE PAGES

Knott, Brandon C.; Nimlos, Claire T.; Robichaud, David J.; ...

2017-12-11

Research efforts in zeolite catalysis have become increasingly cognizant of the diversity in structure and function resulting from the distribution of framework aluminum atoms, through emerging reports of catalytic phenomena that fall outside those recognizable as the shape-selective ones emblematic of its earlier history. Molecular-level descriptions of how active-site distributions affect catalysis are an aspirational goal articulated frequently in experimental and theoretical research, yet they are limited by imprecise knowledge of the structure and behavior of the zeolite materials under interrogation. In experimental research, higher precision can result from more reliable control of structure during synthesis and from more robustmore » and quantitative structural and kinetic characterization probes. In theoretical research, construction of models with specific aluminum locations and distributions seldom capture the heterogeneity inherent to the materials studied by experiment. In this Perspective, we discuss research findings that appropriately frame the challenges in developing more predictive synthesis-structure-function relations for zeolites, highlighting studies on ZSM-5 zeolites that are among the most structurally complex molecular sieve frameworks and the most widely studied because of their versatility in commercial applications. We discuss research directions to address these challenges and forge stronger connections between zeolite structure, composition, and active sites to catalytic function. Such connections promise to aid in bridging the findings of theoretical and experimental catalysis research, and transforming zeolite active site design from an empirical endeavor into a more predictable science founded on validated models.« less

Meeting the challenges of chronic illness: a nurse-led collaborative community care program in Thailand.

PubMed

Sindhu, Siriorn; Pholpet, Chennet; Puttapitukpol, Somjai

2010-01-01

Chronic illness is of concern to health care systems globally. Although a significant evidence base supports the concept of nurse-led interventions, less data is available to address unique features of health care systems in the developing world. The purpose of this study aimed to undertake preliminary testing of an intervention of nurse-led community care program, the Network Collaborative Action Plan (N-CAP), to assess the impact on disease severity and patient satisfaction. A quasi-experimental study, using historical controls, evaluated a collaborative nurse-led intervention to promote coordination and continuity of care for patients with chronic illness. Participants, diagnosed with chronic obstructive lung disease (COPD), coronary heart disease (CHD) and chronic heart failure (CHF) were recruited. Prospective consecutive patient meeting the study criteria (n=47) were assigned into the control group and following development and implementation of the intervention eligible consenting patients were enrolled in the experimental group (n=44). Participants in the experimental group had significantly tower scores on severity of disease measurements during the third week (F = 4.61, p = 0.035) and the eighth week hospital (F = 4.30, p = .041) following hospital discharge than those in the control group. Participants in the experimental group expressed significantly higher scores on satisfaction with community care than those in the control group. A nurse-led, collaboratively developed program has potential to improve satisfaction and decrease symptom development in people with chronic illnesses in Thailand.

Electrical conductivity modeling and experimental study of densely packed SWCNT networks.

PubMed

Jack, D A; Yeh, C-S; Liang, Z; Li, S; Park, J G; Fielding, J C

2010-05-14

Single-walled carbon nanotube (SWCNT) networks have become a subject of interest due to their ability to support structural, thermal and electrical loadings, but to date their application has been hindered due, in large part, to the inability to model macroscopic responses in an industrial product with any reasonable confidence. This paper seeks to address the relationship between macroscale electrical conductivity and the nanostructure of a dense network composed of SWCNTs and presents a uniquely formulated physics-based computational model for electrical conductivity predictions. The proposed model incorporates physics-based stochastic parameters for the individual nanotubes to construct the nanostructure such as: an experimentally obtained orientation distribution function, experimentally derived length and diameter distributions, and assumed distributions of chirality and registry of individual CNTs. Case studies are presented to investigate the relationship between macroscale conductivity and nanostructured variations in the bulk stochastic length, diameter and orientation distributions. Simulation results correspond nicely with those available in the literature for case studies of conductivity versus length and conductivity versus diameter. In addition, predictions for the increasing anisotropy of the bulk conductivity as a function of the tube orientation distribution are in reasonable agreement with our experimental results. Examples are presented to demonstrate the importance of incorporating various stochastic characteristics in bulk conductivity predictions. Finally, a design consideration for industrial applications is discussed based on localized network power emission considerations and may lend insight to the design engineer to better predict network failure under high current loading applications.

Consideration of the Aluminum Distribution in Zeolites in Theoretical and Experimental Catalysis Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Knott, Brandon C.; Nimlos, Claire T.; Robichaud, David J.

Research efforts in zeolite catalysis have become increasingly cognizant of the diversity in structure and function resulting from the distribution of framework aluminum atoms, through emerging reports of catalytic phenomena that fall outside those recognizable as the shape-selective ones emblematic of its earlier history. Molecular-level descriptions of how active-site distributions affect catalysis are an aspirational goal articulated frequently in experimental and theoretical research, yet they are limited by imprecise knowledge of the structure and behavior of the zeolite materials under interrogation. In experimental research, higher precision can result from more reliable control of structure during synthesis and from more robustmore » and quantitative structural and kinetic characterization probes. In theoretical research, construction of models with specific aluminum locations and distributions seldom capture the heterogeneity inherent to the materials studied by experiment. In this Perspective, we discuss research findings that appropriately frame the challenges in developing more predictive synthesis-structure-function relations for zeolites, highlighting studies on ZSM-5 zeolites that are among the most structurally complex molecular sieve frameworks and the most widely studied because of their versatility in commercial applications. We discuss research directions to address these challenges and forge stronger connections between zeolite structure, composition, and active sites to catalytic function. Such connections promise to aid in bridging the findings of theoretical and experimental catalysis research, and transforming zeolite active site design from an empirical endeavor into a more predictable science founded on validated models.« less

A statistical framework for multiparameter analysis at the single-cell level.

PubMed

Torres-García, Wandaliz; Ashili, Shashanka; Kelbauskas, Laimonas; Johnson, Roger H; Zhang, Weiwen; Runger, George C; Meldrum, Deirdre R

2012-03-01

Phenotypic characterization of individual cells provides crucial insights into intercellular heterogeneity and enables access to information that is unavailable from ensemble averaged, bulk cell analyses. Single-cell studies have attracted significant interest in recent years and spurred the development of a variety of commercially available and research-grade technologies. To quantify cell-to-cell variability of cell populations, we have developed an experimental platform for real-time measurements of oxygen consumption (OC) kinetics at the single-cell level. Unique challenges inherent to these single-cell measurements arise, and no existing data analysis methodology is available to address them. Here we present a data processing and analysis method that addresses challenges encountered with this unique type of data in order to extract biologically relevant information. We applied the method to analyze OC profiles obtained with single cells of two different cell lines derived from metaplastic and dysplastic human Barrett's esophageal epithelium. In terms of method development, three main challenges were considered for this heterogeneous dynamic system: (i) high levels of noise, (ii) the lack of a priori knowledge of single-cell dynamics, and (iii) the role of intercellular variability within and across cell types. Several strategies and solutions to address each of these three challenges are presented. The features such as slopes, intercepts, breakpoint or change-point were extracted for every OC profile and compared across individual cells and cell types. The results demonstrated that the extracted features facilitated exposition of subtle differences between individual cells and their responses to cell-cell interactions. With minor modifications, this method can be used to process and analyze data from other acquisition and experimental modalities at the single-cell level, providing a valuable statistical framework for single-cell analysis.

Projects for People: An International Exchange Focused on Drinking Water Quality in Rural Peru

NASA Astrophysics Data System (ADS)

Weathers, T. S.; Tarazona Vasquez, F.; Bailey, E.; Duong, V.; Gonzales Vera, R.; LaPorte, D.; Rojas Cala, B.; Torres Atencia, S.; Vasquez Auqui, J.

2016-12-01

The integration of human-centered design with technical engineering in a classroom setting can be challenging but immensely rewarding if coupled with a community-focused experience. Undergraduate students participated in an international exchange to address drinking water quality in the community of Huamancaca, located in the Junin region of Peru. Technical research and experimentation often comes easily to students in undergraduate engineering programs, however, implementation within a community requires a social license to operate. The objectives of this study were to address the technical challenges of designing a sustainable and effective water filtration system while also ensuring community support and education, coupled with user ownership of the process. In tandem with filter media experimentation with biochar and activated carbon produced using locally available agricultural waste from potatoes and carrots, we visited the people of Huamancaca to understand their needs and concerns. This direct communication with the community was invaluable; we observed that many of the residents' water quality problems could be solved with education. For example, proper sanitation techniques and appropriate addition of bleach or sufficient boiling time may make up for inconsistent water quality provided by the local distribution system. An education plan may also be developed for water treatment plant operators covering chlorine dosage for effective residual treatment within the distribution network in addition to filtration. Upon site visitation and sample collection, we realized that open communication with city officials, operators, business owners, and residents in both technical and social settings is essential for continued collaboration within this community. Solving a tangible problem or designing a product that can be effectively adopted is not a concept that is rigorously addressed in undergraduate education, however the setbacks, challenges, and triumphs experienced when interacting with a community can provide valuable lessons for career development.­

Crack propagation and arrest in CFRP materials with strain softening regions

NASA Astrophysics Data System (ADS)

Dilligan, Matthew Anthony

Understanding the growth and arrest of cracks in composite materials is critical for their effective utilization in fatigue-sensitive and damage susceptible applications such as primary aircraft structures. Local tailoring of the laminate stack to provide crack arrest capacity intermediate to major structural components has been investigated and demonstrated since some of the earliest efforts in composite aerostructural design, but to date no rigorous model of the crack arrest mechanism has been developed to allow effective sizing of these features. To address this shortcoming, the previous work in the field is reviewed, with particular attention to the analysis methodologies proposed for similar arrest features. The damage and arrest processes active in such features are investigated, and various models of these processes are discussed and evaluated. Governing equations are derived based on a proposed mechanistic model of the crack arrest process. The derived governing equations are implemented in a numerical model, and a series of simulations are performed to ascertain the general characteristics of the proposed model and allow qualitative comparison to existing experimental results. The sensitivity of the model and the arrest process to various parameters is investigated, and preliminary conclusions regarding the optimal feature configuration are developed. To address deficiencies in the available material and experimental data, a series of coupon tests are developed and conducted covering a range of arrest zone configurations. Test results are discussed and analyzed, with a particular focus on identification of the proposed failure and arrest mechanisms. Utilizing the experimentally derived material properties, the tests are reproduced with both the developed numerical tool as well as a FEA-based implementation of the arrest model. Correlation between the simulated and experimental results is analyzed, and future avenues of investigation are identified. Utilizing the developed model, a sensitivity study is conducted to assess the current proposed arrest configuration. Optimum distribution and sizing of the arrest zones is investigated, and general design guidelines are developed.

Experimental Evaluation of the IP Address Space Randomisation (IASR) Technique and Its Disruption to Selected Network Services

DTIC Science & Technology

2014-11-01

Canada (Department of National Defence), 2014 c© Sa Majesté la Reine en droit du Canada (Ministère de la Défense nationale), 2014 Abstract In recent...2006), Network security mechanisms utilising network address translation, International journal of critical infrastructures, 2(1), 10–49. [5] Dunlop...Lu, S. (2008), Full service hopping for proactive cyber-defense, In ICNSC 2008: IEEE International Conference on Networking, Sensing and Control, pp

High-Fidelity Modeling of Computer Network Worms

DTIC Science & Technology

2004-06-22

plots the propagation of the TCP-based worm. This execution is among the largest TCP worm models simulated to date at packet-level. TCP vs . UDP Worm...the mapping of the virtual IP addresses to honeyd’s MAC address in the proxy’s ARP table. The proxy server listens for packets from both sides of...experimental setup, we used two ntium-4 ThinkPad , and an IBM Pentium-III ThinkPad ), running the proxy server and honeyd respectively. The Code Red II worm

Analysis of DNA replication associated chromatin decondensation: in vivo assay for understanding chromatin remodeling mechanisms of selected proteins.

PubMed

Borysov, Sergiy; Bryant, Victoria L; Alexandrow, Mark G

2015-01-01

Of critical importance to many of the events underlying transcriptional control of gene expression are modifications to core and linker histones that regulate the accessibility of trans-acting factors to the DNA substrate within the context of chromatin. Likewise, control over the initiation of DNA replication, as well as the ability of the replication machinery to proceed during elongation through the multiple levels of chromatin condensation that are likely to be encountered, is known to involve the creation of chromatin accessibility. In the latter case, chromatin access will likely need to be a transient event so as to prevent total genomic unraveling of the chromatin that would be deleterious to cells. While there are many molecular and biochemical approaches in use to study histone changes and their relationship to transcription and chromatin accessibility, few techniques exist that allow a molecular dissection of the events underlying DNA replication control as it pertains to chromatin changes and accessibility. Here, we outline a novel experimental strategy for addressing the ability of specific proteins to induce large-scale chromatin unfolding (decondensation) in vivo upon site-specific targeting to an engineered locus. Our laboratory has used this powerful system in novel ways to directly address the ability of DNA replication proteins to create chromatin accessibility, and have incorporated modifications to the basic approach that allow for a molecular genetic analysis of the mechanisms and associated factors involved in causing chromatin decondensation by a protein of interest. Alternative approaches involving co-expression of other proteins (competitors or stimulators), concurrent drug treatments, and analysis of co-localizing histone modifications are also addressed, all of which are illustrative of the utility of this experimental system for extending basic findings to physiologically relevant mechanisms. Although used by our group to analyze mechanisms underlying DNA replication associated chromatin accessibility, this unique and powerful experimental system has the propensity to be a valuable tool for understanding chromatin remodeling mechanisms orchestrated by other cellular processes such as DNA repair, recombination, mitotic chromosome condensation, or other chromosome dynamics involving chromatin alterations and accessibility.

Molecular simulations and experimental studies of zeolites

NASA Astrophysics Data System (ADS)

Moloy, Eric C.

Zeolites are microporous aluminosilicate tetrahedral framework materials that have symmetric cages and channels with open-diameters between 0.2 and 2.0 nm. Zeolites are used extensively in the petrochemical industries for both their microporosity and their catalytic properties. The role of water is paramount to the formation, structure, and stability of these materials. Zeolites frequently have extra-framework cations, and as a result, are important ion-exchange materials. Zeolites also play important roles as molecular sieves and catalysts. For all that is known about zeolites, much remains a mystery. How, for example, can the well established metastability of these structures be explained? What is the role of water with respect to the formation, stabilization, and dynamical properties? This dissertation addresses these questions mainly from a modeling perspective, but also with some experimental work as well. The first discussion addresses a special class of zeolites: pure-silica zeolites. Experimental enthalpy of formation data are combined with molecular modeling to address zeolitic metastability. Molecular modeling is used to calculate internal surface areas, and a linear relationship between formation enthalpy and internal surface areas is clearly established, producing an internal surface energy of approximately 93 mJ/m2. Nitrate bearing sodalite and cancrinite have formed under the caustic chemical conditions of some nuclear waste processing centers in the United States. These phases have fouled expensive process equipment, and are the primary constituents of the resilient heels in the bottom of storage tanks. Molecular modeling, including molecular mechanics, molecular dynamics, and density functional theory, is used to simulate these materials with respect to structure and dynamical properties. Some new, very interesting results are extracted from the simulation of anhydrous Na6[Si6Al 6O24] sodalite---most importantly, the identification of two distinct oxygen sites (rather than one), and formation of a new supercell. New calorimetric measurements of enthalpy are used to examine the energetics of the hydrosodalite family of zeolites---specifically, formation enthalpies and hydration energies. Finally, force-field computational methods begin the examination of water in terms of energetics, structure, and radionuclide containment and diffusion.

Geochemical Impacts of Leaking CO2 from Subsurface Storage Reservoirs to Unconfined and Confined Aquifers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Qafoku, Nikolla; Brown, Christopher F.; Wang, Guohui

2013-04-15

Experimental research work has been conducted and is undergoing at Pacific Northwest National Laboratory (PNNL) to address a variety of scientific issues related with the potential leaks of the carbon dioxide (CO2) gas from deep storage reservoirs. The main objectives of this work are as follows: • Develop a systematic understanding of how CO2 leakage is likely to influence pertinent geochemical processes (e.g., dissolution/precipitation, sorption/desorption and redox reactions) in the aquifer sediments. • Identify prevailing environmental conditions that would dictate one geochemical outcome over another. • Gather useful information to support site selection, risk assessment, policy-making, and public education effortsmore » associated with geological carbon sequestration. In this report, we present results from experiments conducted at PNNL to address research issues related to the main objectives of this effort. A series of batch and column experiments and solid phase characterization studies (quantitative x-ray diffraction and wet chemical extractions with a concentrated acid) were conducted with representative rocks and sediments from an unconfined, oxidizing carbonate aquifer, i.e., Edwards aquifer in Texas, and a confined aquifer, i.e., the High Plains aquifer in Kansas. These materials were exposed to a CO2 gas stream simulating CO2 gas leaking scenarios, and changes in aqueous phase pH and chemical composition were measured in liquid and effluent samples collected at pre-determined experimental times. Additional research to be conducted during the current fiscal year will further validate these results and will address other important remaining issues. Results from these experimental efforts will provide valuable insights for the development of site-specific, generation III reduced order models. In addition, results will initially serve as input parameters during model calibration runs and, ultimately, will be used to test model predictive capability and competency. The results from these investigations will provide useful information to support site selection, risk assessment, and public education efforts associated with geological, deep subsurface CO2 storage and sequestration.« less

Strong fields and neutral particle magnetic moment dynamics

NASA Astrophysics Data System (ADS)

Formanek, Martin; Evans, Stefan; Rafelski, Johann; Steinmetz, Andrew; Yang, Cheng-Tao

2018-07-01

Interaction of magnetic moment of point particles with external electromagnetic fields experiences unresolved theoretical and experimental discrepancies. In this work we point out several issues within relativistic quantum mechanics and QED and we describe effects related to a new covariant classical model of magnetic moment dynamics. Using this framework we explore the invariant acceleration experienced by neutral particles coupled to an external plane wave field through the magnetic moment: we study the case of ultrarelativistic Dirac neutrinos with magnetic moment in the range of 10‑11 to 10‑20 μ B; and we address the case of slowly moving neutrons. We explore how critical accelerations for neutrinos can be experimentally achieved in laser pulse interactions. The radiation of accelerated neutrinos can serve as an important test distinguishing between Majorana and Dirac nature of neutrinos.

Experimental comparison of inquiry and direct instruction in science

NASA Astrophysics Data System (ADS)

Cobern, William W.; Schuster, David; Adams, Betty; Applegate, Brooks; Skjold, Brandy; Undreiu, Adriana; Loving, Cathleen C.; Gobert, Janice D.

2010-04-01

There are continuing educational and political debates about 'inquiry' versus 'direct' teaching of science. Traditional science instruction has been largely direct but in the US, recent national and state science education standards advocate inquiry throughout K-12 education. While inquiry-based instruction has the advantage of modelling aspects of the nature of real scientific inquiry, there is little unconfounded comparative research into the effectiveness and efficiency of the two instructional modes for developing science conceptual understanding. This research undertook a controlled experimental study comparing the efficacy of carefully designed inquiry instruction and equally carefully designed direct instruction in realistic science classroom situations at the middle school grades. The research design addressed common threats to validity. We report on the nature of the instructional units in each mode, research design, methods, classroom implementations, monitoring, assessments, analysis and project findings.

Correlated prompt fission data in transport simulations

DOE PAGES

Talou, P.; Vogt, R.; Randrup, J.; ...

2018-01-24

Detailed information on the fission process can be inferred from the observation, modeling and theoretical understanding of prompt fission neutron and γ-ray observables. Beyond simple average quantities, the study of distributions and correlations in prompt data, e.g., multiplicity-dependent neutron and γ-ray spectra, angular distributions of the emitted particles, n -n, n - γ, and γ - γ correlations, can place stringent constraints on fission models and parameters that would otherwise be free to be tuned separately to represent individual fission observables. The FREYA and CGMF codes have been developed to follow the sequential emissions of prompt neutrons and γ raysmore » from the initial excited fission fragments produced right after scission. Both codes implement Monte Carlo techniques to sample initial fission fragment configurations in mass, charge and kinetic energy and sample probabilities of neutron and γ emission at each stage of the decay. This approach naturally leads to using simple but powerful statistical techniques to infer distributions and correlations among many observables and model parameters. The comparison of model calculations with experimental data provides a rich arena for testing various nuclear physics models such as those related to the nuclear structure and level densities of neutron-rich nuclei, the γ-ray strength functions of dipole and quadrupole transitions, the mechanism for dividing the excitation energy between the two nascent fragments near scission, and the mechanisms behind the production of angular momentum in the fragments, etc. Beyond the obvious interest from a fundamental physics point of view, such studies are also important for addressing data needs in various nuclear applications. The inclusion of the FREYA and CGMF codes into the MCNP6.2 and MCNPX - PoliMi transport codes, for instance, provides a new and powerful tool to simulate correlated fission events in neutron transport calculations important in nonproliferation, safeguards, nuclear energy, and defense programs. Here, this review provides an overview of the topic, starting from theoretical considerations of the fission process, with a focus on correlated signatures. It then explores the status of experimental correlated fission data and current efforts to address some of the known shortcomings. Numerical simulations employing the FREYA and CGMF codes are compared to experimental data for a wide range of correlated fission quantities. The inclusion of those codes into the MCNP6.2 and MCNPX - PoliMi transport codes is described and discussed in the context of relevant applications. The accuracy of the model predictions and their sensitivity to model assumptions and input parameters are discussed. Lastly, a series of important experimental and theoretical questions that remain unanswered are presented, suggesting a renewed effort to address these shortcomings.« less

Correlated prompt fission data in transport simulations

NASA Astrophysics Data System (ADS)

Talou, P.; Vogt, R.; Randrup, J.; Rising, M. E.; Pozzi, S. A.; Verbeke, J.; Andrews, M. T.; Clarke, S. D.; Jaffke, P.; Jandel, M.; Kawano, T.; Marcath, M. J.; Meierbachtol, K.; Nakae, L.; Rusev, G.; Sood, A.; Stetcu, I.; Walker, C.

2018-01-01

Detailed information on the fission process can be inferred from the observation, modeling and theoretical understanding of prompt fission neutron and γ-ray observables. Beyond simple average quantities, the study of distributions and correlations in prompt data, e.g., multiplicity-dependent neutron and γ-ray spectra, angular distributions of the emitted particles, n - n, n - γ, and γ - γ correlations, can place stringent constraints on fission models and parameters that would otherwise be free to be tuned separately to represent individual fission observables. The FREYA and CGMF codes have been developed to follow the sequential emissions of prompt neutrons and γ rays from the initial excited fission fragments produced right after scission. Both codes implement Monte Carlo techniques to sample initial fission fragment configurations in mass, charge and kinetic energy and sample probabilities of neutron and γ emission at each stage of the decay. This approach naturally leads to using simple but powerful statistical techniques to infer distributions and correlations among many observables and model parameters. The comparison of model calculations with experimental data provides a rich arena for testing various nuclear physics models such as those related to the nuclear structure and level densities of neutron-rich nuclei, the γ-ray strength functions of dipole and quadrupole transitions, the mechanism for dividing the excitation energy between the two nascent fragments near scission, and the mechanisms behind the production of angular momentum in the fragments, etc. Beyond the obvious interest from a fundamental physics point of view, such studies are also important for addressing data needs in various nuclear applications. The inclusion of the FREYA and CGMF codes into the MCNP6.2 and MCNPX - PoliMi transport codes, for instance, provides a new and powerful tool to simulate correlated fission events in neutron transport calculations important in nonproliferation, safeguards, nuclear energy, and defense programs. This review provides an overview of the topic, starting from theoretical considerations of the fission process, with a focus on correlated signatures. It then explores the status of experimental correlated fission data and current efforts to address some of the known shortcomings. Numerical simulations employing the FREYA and CGMF codes are compared to experimental data for a wide range of correlated fission quantities. The inclusion of those codes into the MCNP6.2 and MCNPX - PoliMi transport codes is described and discussed in the context of relevant applications. The accuracy of the model predictions and their sensitivity to model assumptions and input parameters are discussed. Finally, a series of important experimental and theoretical questions that remain unanswered are presented, suggesting a renewed effort to address these shortcomings.

Correlated prompt fission data in transport simulations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Talou, P.; Vogt, R.; Randrup, J.

Detailed information on the fission process can be inferred from the observation, modeling and theoretical understanding of prompt fission neutron and γ-ray observables. Beyond simple average quantities, the study of distributions and correlations in prompt data, e.g., multiplicity-dependent neutron and γ-ray spectra, angular distributions of the emitted particles, n -n, n - γ, and γ - γ correlations, can place stringent constraints on fission models and parameters that would otherwise be free to be tuned separately to represent individual fission observables. The FREYA and CGMF codes have been developed to follow the sequential emissions of prompt neutrons and γ raysmore » from the initial excited fission fragments produced right after scission. Both codes implement Monte Carlo techniques to sample initial fission fragment configurations in mass, charge and kinetic energy and sample probabilities of neutron and γ emission at each stage of the decay. This approach naturally leads to using simple but powerful statistical techniques to infer distributions and correlations among many observables and model parameters. The comparison of model calculations with experimental data provides a rich arena for testing various nuclear physics models such as those related to the nuclear structure and level densities of neutron-rich nuclei, the γ-ray strength functions of dipole and quadrupole transitions, the mechanism for dividing the excitation energy between the two nascent fragments near scission, and the mechanisms behind the production of angular momentum in the fragments, etc. Beyond the obvious interest from a fundamental physics point of view, such studies are also important for addressing data needs in various nuclear applications. The inclusion of the FREYA and CGMF codes into the MCNP6.2 and MCNPX - PoliMi transport codes, for instance, provides a new and powerful tool to simulate correlated fission events in neutron transport calculations important in nonproliferation, safeguards, nuclear energy, and defense programs. Here, this review provides an overview of the topic, starting from theoretical considerations of the fission process, with a focus on correlated signatures. It then explores the status of experimental correlated fission data and current efforts to address some of the known shortcomings. Numerical simulations employing the FREYA and CGMF codes are compared to experimental data for a wide range of correlated fission quantities. The inclusion of those codes into the MCNP6.2 and MCNPX - PoliMi transport codes is described and discussed in the context of relevant applications. The accuracy of the model predictions and their sensitivity to model assumptions and input parameters are discussed. Lastly, a series of important experimental and theoretical questions that remain unanswered are presented, suggesting a renewed effort to address these shortcomings.« less

A sparse equivalent source method for near-field acoustic holography.

PubMed

Fernandez-Grande, Efren; Xenaki, Angeliki; Gerstoft, Peter

2017-01-01

This study examines a near-field acoustic holography method consisting of a sparse formulation of the equivalent source method, based on the compressive sensing (CS) framework. The method, denoted Compressive-Equivalent Source Method (C-ESM), encourages spatially sparse solutions (based on the superposition of few waves) that are accurate when the acoustic sources are spatially localized. The importance of obtaining a non-redundant representation, i.e., a sensing matrix with low column coherence, and the inherent ill-conditioning of near-field reconstruction problems is addressed. Numerical and experimental results on a classical guitar and on a highly reactive dipole-like source are presented. C-ESM is valid beyond the conventional sampling limits, making wide-band reconstruction possible. Spatially extended sources can also be addressed with C-ESM, although in this case the obtained solution does not recover the spatial extent of the source.