Sample records for factor experimental evaluation

  1. A straightforward experimental method to evaluate the Lamb-Mössbauer factor of a 57Co/Rh source

    NASA Astrophysics Data System (ADS)

    Spina, G.; Lantieri, M.

    2014-01-01

    In analyzing Mössbauer spectra by means of the integral transmission function, a correct evaluation of the recoilless fs factor of the source at the position of the sample is needed. A novel method to evaluate fs for a 57Co source is proposed. The method uses the standard transmission experimental set up and it does not need further measurements but the ones that are mandatory in order to center the Mössbauer line and to calibrate the Mössbauer transducer. Firstly, the background counts are evaluated by collecting a standard Multi Channel Scaling (MCS) spectrum of a tick metal iron foil absorber and two Pulse Height Analysis (PHA) spectra with the same life-time and setting the maximum velocity of the transducer at the same value of the MCS spectrum. Secondly, fs is evaluated by fitting the collected MCS spectrum throughout the integral transmission approach. A test of the suitability of the technique is presented, too.

  2. EXPERIMENTAL APPROACHES TO EVALUATING THE ROLE OF ENVIRONMENTAL FACTORS IN THE DEVELOPMENT OF CARDIOVASCULAR DISEASE

    EPA Science Inventory

    Epidemiologic studies have suggested factors in drinking water influence on the human cardiovascular system. A clear identification of the factors involved requires more invasive techniques and more strict experimental controls than can usually be applied in epidemiologic studies...

  3. A Model for Evaluating Programs for the Gifted under Non-Experimental Conditions.

    ERIC Educational Resources Information Center

    Carter, Kyle R.

    1992-01-01

    The article presents and illustrates use of an evaluation model for assessing programs for the gifted where tight experimental control is not possible. The model consists of four components: ex post factor designs including intact groups; comparative evaluation; strength of treatment; and multiple outcome assessment from flexible data sources. (DB)

  4. Experimental evaluation of clinical colon anastomotic leakage.

    PubMed

    Pommergaard, Hans-Christian

    2014-03-01

    Colorectal anastomotic leakage remains a frequent and serious complication in gastrointestinal surgery. Patient and procedure related risk factors for anastomotic leakage have been identified. However, the responsible pathophysiological mechanisms are still unknown. Among these, ischemia and insufficient surgical technique have been suggested to play a central role. Animal models are valuable means to evaluate pathophysiological mechanisms and may be used to test preventive measures aiming at reducing the risk of anastomotic leakage, such as external anastomotic coating. The aim of this thesis was to: Clarify the best suited animal to model clinical anastomotic leakage in humans; Create animal models mimicking anastomotic leakage in humans induced by insufficient surgical technique and tissue ischemia; Determine the best suited coating materials to prevent anastomotic leakage. This study is a systematic review using the databases MEDLINE and Rex. MEDLINE was searched up to October 2010 to identify studies on experimental animal models of clinical colon anastomotic leakage. From the Rex database, textbooks on surgical aspects as well as gastrointestinal physiology and anatomy of experimental animals were identified. The results indicated that the mouse and the pig are the best suited animals to evaluate clinical anastomotic leakage. However, the pig model is less validated and more costly to use compared with the mouse. Most frequently, rats are used as models. However, extreme interventions are needed to create clinical leakage in these animals. The knowledge from this study formed the basis for selecting the animal species most suited for the models in the next studies. STUDY 2: In this experimental study, technically insufficient colonic anastomoses were performed in 110 C57BL/6 mice. The number of sutures in the intervention group was reduced to produce a suitable leakage rate. Moreover, the analgesia and suture material were changed in order to optimize the

  5. Factors affecting large peakflows on Appalachian watersheds: lessons from the Fernow Experimental Forest

    Treesearch

    James N. Kochenderfer; Mary Beth Adams; Gary W. Miller; David J. Helvey

    2007-01-01

    Data collected since 1951 on the Fernow Experimental Forest near Parsons, West Virginia, and at a gaging station on the nearby Cheat River since 1913 were used to evaluate factors affecting large peakflows on forested watersheds. Treatments ranged from periodic partial cuts to complete deforestation using herbicides. Total storm precipitation and average storm...

  6. Evaluation of experimental flexible pavements : final report.

    DOT National Transportation Integrated Search

    1979-01-01

    The construction and performance of seven Virginia flexible pavements containing at least some experimental features were evaluated. The objective was to evaluate the performance of the pavements incorporating new or timely design concepts and to ass...

  7. Experimental and evaluated photoneutron cross sections for 197Au

    NASA Astrophysics Data System (ADS)

    Varlamov, V.; Ishkhanov, B.; Orlin, V.

    2017-10-01

    There is a serious well-known problem of noticeable disagreements between the partial photoneutron cross sections obtained in various experiments. Such data were mainly determined using quasimonoenergetic annihilation photon beams and the method of neutron multiplicity sorting at Lawrence Livermore National Laboratory (USA) and Centre d'Etudes Nucleaires of Saclay (France). The analysis of experimental cross sections employing new objective physical data reliability criteria has shown that many of those are not reliable. The IAEA Coordinated Research Project (CRP) on photonuclear data evaluation was approved. The experimental and previously evaluated cross sections of the partial photoneutron reactions (γ ,1 n ) and (γ ,2 n ) on 197Au were analyzed using the new data reliability criteria. The data evaluated using the new experimental-theoretical method noticeably differ from both experimental data and data previously evaluated using nuclear modeling codes gnash, gunf, alice-f, and others. These discrepancies needed to be resolved.

  8. Cholangiocyte Endothelin 1 and Transforming Growth Factor β1 Production in Rat Experimental Hepatopulmonary Syndrome

    PubMed Central

    LUO, BAO; TANG, LIPING; WANG, ZHISHAN; ZHANG, JUNLAN; LING, YIQUN; FENG, WENGUANG; SUN, JU-ZHONG; STOCKARD, CECIL R.; FROST, ANDRA R.; CHEN, YIU-FAI; GRIZZLE, WILLIAM E.; FALLON, MICHAEL B.

    2010-01-01

    Background & Aims Hepatic production and release of endothelin 1 plays a central role in experimental hepatopulmonary syndrome after common bile duct ligation by stimulating pulmonary endothelial nitric oxide production. In thioacetamide-induced nonbiliary cirrhosis, hepatic endothelin 1 production and release do not occur, and hepatopulmonary syndrome does not develop. However, the source and regulation of hepatic endothelin 1 after common bile duct ligation are not fully characterized. We evaluated the sources of hepatic endothelin 1 production after common bile duct ligation in relation to thioacetamide cirrhosis and assessed whether transforming growth factor β1 regulates endothelin 1 production. Methods Hepatopulmonary syndrome and hepatic and plasma endothelin 1 levels were evaluated after common bile duct ligation or thioacetamide administration. Cellular sources of endothelin 1 were assessed by immunohistochemistry and laser capture microdissection of cholangiocytes. Transforming growth factor β1 expression and signaling were assessed by using immunohistochemistry and Western blotting and by evaluating normal rat cholangiocytes. Results Hepatic and plasma endothelin 1 levels increased and hepatopulmonary syndrome developed only after common bile duct ligation. Hepatic endothelin 1 and transforming growth factor β1 levels increased over a similar time frame, and cholangiocytes were a major source of each peptide. Transforming growth factor β1 signaling in cholangiocytes in vivo was evident by increased phosphorylation and nuclear localization of Smad2, and hepatic endothelin 1 levels correlated directly with liver transforming growth factor β1 and phosphorylated Smad2 levels. Transforming growth factor β1 also stimulated endothelin 1 promoter activity, expression, and production in normal rat cholangiocytes. Conclusions Cholangiocytes are a major source of hepatic endothelin 1 production during the development of hepatopulmonary syndrome after common

  9. Experimental Evaluation Methodology for Spacecraft Proximity Maneuvers in a Dynamic Environment

    DTIC Science & Technology

    2017-06-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA DISSERTATION EXPERIMENTAL EVALUATION METHODOLOGY FOR SPACECRAFT PROXIMITY MANEUVERS IN A DYNAMIC...29, 2014 – June 16, 2017 4. TITLE AND SUBTITLE EXPERIMENTAL EVALUATION METHODOLOGY FOR SPACECRAFT PROXIMITY MANEUVERS IN A DYNAMIC ENVIRONMENT 5...LEFT BLANK ii Approved for public release. Distribution is unlimited. EXPERIMENTAL EVALUATION METHODOLOGY FOR SPACECRAFT PROXIMITY MANEUVERS IN A

  10. Motivation in vigilance - Effects of self-evaluation and experimenter-controlled feedback.

    NASA Technical Reports Server (NTRS)

    Warm, J. S.; Kanfer, F. H.; Kuwada, S.; Clark, J. L.

    1972-01-01

    Vigilance experiments have been performed to study the relative efficiency of feedback operations in enhancing vigilance performance. Two feedback operations were compared - i.e., experimenter-controlled feedback in the form of knowledge of results (KR) regarding response times to signal detections, and subject-controlled feedback in the form of self-evaluation (SE) of response times to signal detections. The subjects responded to the aperiodic offset of a visual signal during a 1-hr vigil. Both feedback operations were found to enhance performance efficiency: subjects in the KR and SE conditions had faster response times than controls receiving no evaluative feedback. Moreover, the data of the KR and SE groups did not differ significantly from each other. The results are discussed in terms of the hypothesis that self-evaluation is a critical factor underlying the incentive value of KR in vigilance tasks.

  11. Experimental Evaluation and Workload Characterization for High-Performance Computer Architectures

    NASA Technical Reports Server (NTRS)

    El-Ghazawi, Tarek A.

    1995-01-01

    This research is conducted in the context of the Joint NSF/NASA Initiative on Evaluation (JNNIE). JNNIE is an inter-agency research program that goes beyond typical.bencbking to provide and in-depth evaluations and understanding of the factors that limit the scalability of high-performance computing systems. Many NSF and NASA centers have participated in the effort. Our research effort was an integral part of implementing JNNIE in the NASA ESS grand challenge applications context. Our research work under this program was composed of three distinct, but related activities. They include the evaluation of NASA ESS high- performance computing testbeds using the wavelet decomposition application; evaluation of NASA ESS testbeds using astrophysical simulation applications; and developing an experimental model for workload characterization for understanding workload requirements. In this report, we provide a summary of findings that covers all three parts, a list of the publications that resulted from this effort, and three appendices with the details of each of the studies using a key publication developed under the respective work.

  12. A Review of Out-of-School Time Program Quasi-Experimental and Experimental Evaluation Results. Out-of-School Time Evaluation Snapshot.

    ERIC Educational Resources Information Center

    Little, Priscilla M. D.; Harris, Erin

    As the amount of resources allocated to out-of-school (OST) programming and policymakers' demands for research-based results increase, there is increasing interest in rigorous research designs to examine OST program outcomes. This issue of "Out-of-School Time Evaluation Snapshots" reviews 27 quasi-experimental and experimental OST…

  13. Cross-checking of Large Evaluated and Experimental Nuclear Reaction Databases

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

    Zeydina, O.; Koning, A.J.; Soppera, N.

    2014-06-15

    Automated methods are presented for the verification of large experimental and evaluated nuclear reaction databases (e.g. EXFOR, JEFF, TENDL). These methods allow an assessment of the overall consistency of the data and detect aberrant values in both evaluated and experimental databases.

  14. Experimental evaluations of wearable ECG monitor.

    PubMed

    Ha, Kiryong; Kim, Youngsung; Jung, Junyoung; Lee, Jeunwoo

    2008-01-01

    Healthcare industry is changing with ubiquitous computing environment and wearable ECG measurement is one of the most popular approaches in this healthcare industry. Reliability and performance of healthcare device is fundamental issue for widespread adoptions, and interdisciplinary perspectives of wearable ECG monitor make this more difficult. In this paper, we propose evaluation criteria considering characteristic of both ECG measurement and ubiquitous computing. With our wearable ECG monitors, various levels of experimental analysis are performed based on evaluation strategy.

  15. Bioremediation of chlorpyrifos contaminated soil by two phase bioslurry reactor: Processes evaluation and optimization by Taguchi's design of experimental (DOE) methodology.

    PubMed

    Pant, Apourv; Rai, J P N

    2018-04-15

    Two phase bioreactor was constructed, designed and developed to evaluate the chlorpyrifos remediation. Six biotic and abiotic factors (substrate-loading rate, slurry phase pH, slurry phase dissolved oxygen (DO), soil water ratio, temperature and soil micro flora load) were evaluated by design of experimental (DOE) methodology employing Taguchi's orthogonal array (OA). The selected six factors were considered at two levels L-8 array (2^7, 15 experiments) in the experimental design. The optimum operating conditions obtained from the methodology showed enhanced chlorpyrifos degradation from 283.86µg/g to 955.364µg/g by overall 70.34% of enhancement. In the present study, with the help of few well defined experimental parameters a mathematical model was constructed to understand the complex bioremediation process and optimize the approximate parameters upto great accuracy. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Experimental Evaluation of Textbooks and Multimedia.

    ERIC Educational Resources Information Center

    Mikk, Jaan

    This paper begins by providing an overview of three types of textbook research methods: asking teachers, parents, or students about the different aspects of textbook quality; textbook analysis, i.e. counting some characteristics of a textbook using strictly fixed rules; and the experimental evaluation of textbooks, usually carried out in schools.…

  17. Evaluation of sperm motility with CASA-Mot: which factors may influence our measurements?

    PubMed

    Yeste, Marc; Bonet, Sergi; Rodríguez-Gil, Joan E; Rivera Del Álamo, Maria M

    2018-03-14

    Computer-aided sperm analysis (CASA) is now routinely used in IVF clinics, animal breeding centres and research laboratories. Although CASA provides a more objective way to evaluate sperm parameters, a significant number of factors can affect these measurements. This paper classifies these factors into four categories: (1) sample and slide (e.g. preincubation time, type of specimen and type of chamber slide); (2) microscope (e.g. light source and microscope stage); (3) hardware and software, including the settings of each system; and (4) user-related factors. We review the effects of the different factors in each category on the measurements made and emphasise the need to take measures to standardise evaluations. The take-home message of the present article is that there are several commercial and useful CASA systems, and all are appropriate for routine analysis. Non-commercial systems may also be good choices when the user needs to adapt the device to specific experimental conditions. In both cases (commercial and non-commercial), it is important that standard protocols are put in place for evaluation, as well as methods to validate the system.

  18. Experimental study and evaluation of radioprotective drugs

    NASA Technical Reports Server (NTRS)

    Smith, D. E.; Thomson, J. F.

    1968-01-01

    Experimental study evaluates radioprotective drugs administered before exposure either orally or intravenously. Specifically studied are the sources of radiation, choice of radiation dose, choice of animals, administration of drugs, the toxicity of protective agents and types of protective drug.

  19. Experimental Evaluation of Processing Time for the Synchronization of XML-Based Business Objects

    NASA Astrophysics Data System (ADS)

    Ameling, Michael; Wolf, Bernhard; Springer, Thomas; Schill, Alexander

    Business objects (BOs) are data containers for complex data structures used in business applications such as Supply Chain Management and Customer Relationship Management. Due to the replication of application logic, multiple copies of BOs are created which have to be synchronized and updated. This is a complex and time consuming task because BOs rigorously vary in their structure according to the distribution, number and size of elements. Since BOs are internally represented as XML documents, the parsing of XML is one major cost factor which has to be considered for minimizing the processing time during synchronization. The prediction of the parsing time for BOs is an significant property for the selection of an efficient synchronization mechanism. In this paper, we present a method to evaluate the influence of the structure of BOs on their parsing time. The results of our experimental evaluation incorporating four different XML parsers examine the dependencies between the distribution of elements and the parsing time. Finally, a general cost model will be validated and simplified according to the results of the experimental setup.

  20. Hand function evaluation: a factor analysis study.

    PubMed

    Jarus, T; Poremba, R

    1993-05-01

    The purpose of this study was to investigate hand function evaluations. Factor analysis with varimax rotation was used to assess the fundamental characteristics of the items included in the Jebsen Hand Function Test and the Smith Hand Function Evaluation. The study sample consisted of 144 subjects without disabilities and 22 subjects with Colles fracture. Results suggest a four factor solution: Factor I--pinch movement; Factor II--grasp; Factor III--target accuracy; and Factor IV--activities of daily living. These categories differentiated the subjects without Colles fracture from the subjects with Colles fracture. A hand function evaluation consisting of these four factors would be useful. Such an evaluation that can be used for current clinical purposes is provided.

  1. Monetary conversion factors for economic evaluations of substance use disorders.

    PubMed

    McCollister, Kathryn; Yang, Xuan; Sayed, Bisma; French, Michael T; Leff, Jared A; Schackman, Bruce R

    2017-10-01

    Estimating the economic consequences of substance use disorders (SUDs) is important for evaluating existing programs and new interventions. Policy makers in particular must weigh program effectiveness with scalability and sustainability considerations in deciding which programs to fund with limited resources. This study provides a comprehensive list of monetary conversion factors for a broad range of consequences, services, and outcomes, which can be used in economic evaluations of SUD interventions (primarily in the United States), including common co-occurring conditions such as HCV and HIV. Economic measures were selected from standardized clinical assessment instruments that are used in randomized clinical trials and other research studies (e.g., quasi-experimental community-based projects) to evaluate the impact of SUD interventions. National datasets were also reviewed for additional SUD-related consequences, services, and outcomes. Monetary conversion factors were identified through a comprehensive literature review of published articles as well as targeted searches of other sources such as government reports. Eight service/consequence/outcome domains were identified containing more than sixty monetizable measures of medical and behavioral health services, laboratory services, SUD treatment, social services, productivity outcomes, disability outcomes, criminal activity and criminal justice services, and infectious diseases consequences. Unit-specific monetary conversion factors are reported, along with upper and lower bound estimates, whenever possible. Having an updated and standardized source of monetary conversion factors will facilitate and improve future economic evaluations of interventions targeting SUDs and other risky behaviors. This exercise should be repeated periodically as new sources of data become available to maintain the timeliness, comprehensiveness, and quality of these estimates. Copyright © 2017 The Authors. Published by Elsevier Inc

  2. Quasi-experimental evaluation without regression analysis.

    PubMed

    Rohrer, James E

    2009-01-01

    Evaluators of public health programs in field settings cannot always randomize subjects into experimental or control groups. By default, they may choose to employ the weakest study design available: the pretest, posttest approach without a comparison group. This essay argues that natural experiments involving comparison groups are within reach of public health program managers. Methods for analyzing natural experiments are discussed.

  3. Evaluation of experimental flexible pavements : interim report no. 2.

    DOT National Transportation Integrated Search

    1975-01-01

    A program of construction and performance evaluation of seven Virginia flexible pavements containing at least some experimental features is reported. The objective of the program is to evaluate the performance of the pavements incorporating new or ti...

  4. 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

  5. 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.

  6. An Experimental Testbed for Evaluation of Trust and Reputation Systems

    NASA Astrophysics Data System (ADS)

    Kerr, Reid; Cohen, Robin

    To date, trust and reputation systems have often been evaluated using methods of their designers’ own devising. Recently, we demonstrated that a number of noteworthy trust and reputation systems could be readily defeated, revealing limitations in their original evaluations. Efforts in the trust and reputation community to develop a testbed have yielded a successful competition platform, ART. This testbed, however, is less suited to general experimentation and evaluation of individual trust and reputation technologies. In this paper, we propose an experimentation and evaluation testbed based directly on that used in our investigations into security vulnerabilities in trust and reputation systems for marketplaces. We demonstrate the advantages of this design, towards the development of more thorough, objective evaluations of trust and reputation systems.

  7. Enhancement factor in low-coherence enhanced backscattering and its applications for characterizing experimental skin carcinogenesis

    NASA Astrophysics Data System (ADS)

    Liu, Jingjing; Xu, Zhengbin; Song, Qinghai; Konger, Raymond L.; Kim, Young L.

    2010-05-01

    We experimentally study potential mechanisms by which the enhancement factor in low-coherence enhanced backscattering (LEBS) can probe subtle variations in radial intensity distribution in weakly scattering media. We use enhanced backscattering of light by implementing either (1) low spatial coherence illumination or (2) multiple spatially independent detections using a microlens array under spatially coherent illumination. We show that the enhancement factor in these configurations is a measure of the integrated intensity within the localized coherence or detection area, which can exhibit strong dependence on small perturbations in scattering properties. To further evaluate the utility of the LEBS enhancement factor, we use a well-established animal model of cutaneous two-stage chemical carcinogenesis. In this pilot study, we demonstrate that the LEBS enhancement factor can be substantially altered at a stage of preneoplasia. Our animal result supports the idea that early carcinogenesis can cause subtle alterations in the scattering properties that can be captured by the LEBS enhancement factor. Thus, the LEBS enhancement factor has the potential as an easily measurable biomarker in skin carcinogenesis.

  8. An evaluation of the carbon balance technique for estimating emission factors and fuel consumption in forest fires

    Treesearch

    Nelson, Jr. Ralph M.

    1982-01-01

    Eighteen experimental fires were used to compare measured and calculated values for emission factors and fuel consumption to evaluate the carbon balance technique. The technique is based on a model for the emission factor of carbon dioxide, corrected for the production of other emissions, and which requires measurements of effluent concentrations and air volume in the...

  9. Experimental system, and its evaluation for the control of surgically inducted infections

    NASA Technical Reports Server (NTRS)

    Tevebaugh, M. D.; Nelson, J. P.

    1972-01-01

    The effect is reported to design, fabricate, test and evaluate a prototype experimental system for the control of surgically induced infections. The purpose is to provide the cleanest possible environment within a hospital surgery room and eliminate contamination sources that could cause infections during surgery. The system design is described. The system provides for a portable laminar flow clean room, a full bubble helmet system with associated communications and ventilation subsystems for operating room personnel, and surgical gowns that minimize the migration of bacteria. The development test results consisting of portability, laminar flowrate, air flow pattern, electrostatic buildup, noise level, ventilation, human factors, electrical and material compatibility tests are summarized. The conclusions are that the experimental system is effective in reducing the airborne and wound contamination although the helmets and gowns may not be a significant part of this reduction. Definitive conclusions with regard to the infection rate cannot be made at this time.

  10. Impact of measurement uncertainty from experimental load distribution factors on bridge load rating

    NASA Astrophysics Data System (ADS)

    Gangone, Michael V.; Whelan, Matthew J.

    2018-03-01

    Load rating and testing of highway bridges is important in determining the capacity of the structure. Experimental load rating utilizes strain transducers placed at critical locations of the superstructure to measure normal strains. These strains are then used in computing diagnostic performance measures (neutral axis of bending, load distribution factor) and ultimately a load rating. However, it has been shown that experimentally obtained strain measurements contain uncertainties associated with the accuracy and precision of the sensor and sensing system. These uncertainties propagate through to the diagnostic indicators that in turn transmit into the load rating calculation. This paper will analyze the effect that measurement uncertainties have on the experimental load rating results of a 3 span multi-girder/stringer steel and concrete bridge. The focus of this paper will be limited to the uncertainty associated with the experimental distribution factor estimate. For the testing discussed, strain readings were gathered at the midspan of each span of both exterior girders and the center girder. Test vehicles of known weight were positioned at specified locations on each span to generate maximum strain response for each of the five girders. The strain uncertainties were used in conjunction with a propagation formula developed by the authors to determine the standard uncertainty in the distribution factor estimates. This distribution factor uncertainty is then introduced into the load rating computation to determine the possible range of the load rating. The results show the importance of understanding measurement uncertainty in experimental load testing.

  11. Theoretical and experimental study of a new algorithm for factoring numbers

    NASA Astrophysics Data System (ADS)

    Tamma, Vincenzo

    The security of codes, for example in credit card and government information, relies on the fact that the factorization of a large integer N is a rather costly process on a classical digital computer. Such a security is endangered by Shor's algorithm which employs entangled quantum systems to find, with a polynomial number of resources, the period of a function which is connected with the factors of N. We can surely expect a possible future realization of such a method for large numbers, but so far the period of Shor's function has been only computed for the number 15. Inspired by Shor's idea, our work aims to methods of factorization based on the periodicity measurement of a given continuous periodic "factoring function" which is physically implementable using an analogue computer. In particular, we have focused on both the theoretical and the experimental analysis of Gauss sums with continuous arguments leading to a new factorization algorithm. The procedure allows, for the first time, to factor several numbers by measuring the periodicity of Gauss sums performing first-order "factoring" interfer ence processes. We experimentally implemented this idea by exploiting polychromatic optical interference in the visible range with a multi-path interferometer, and achieved the factorization of seven digit numbers. The physical principle behind this "factoring" interference procedure can be potentially exploited also on entangled systems, as multi-photon entangled states, in order to achieve a polynomial scaling in the number of resources.

  12. Experimental realization of Shor's quantum factoring algorithm using nuclear magnetic resonance.

    PubMed

    Vandersypen, L M; Steffen, M; Breyta, G; Yannoni, C S; Sherwood, M H; Chuang, I L

    The number of steps any classical computer requires in order to find the prime factors of an l-digit integer N increases exponentially with l, at least using algorithms known at present. Factoring large integers is therefore conjectured to be intractable classically, an observation underlying the security of widely used cryptographic codes. Quantum computers, however, could factor integers in only polynomial time, using Shor's quantum factoring algorithm. Although important for the study of quantum computers, experimental demonstration of this algorithm has proved elusive. Here we report an implementation of the simplest instance of Shor's algorithm: factorization of N = 15 (whose prime factors are 3 and 5). We use seven spin-1/2 nuclei in a molecule as quantum bits, which can be manipulated with room temperature liquid-state nuclear magnetic resonance techniques. This method of using nuclei to store quantum information is in principle scalable to systems containing many quantum bits, but such scalability is not implied by the present work. The significance of our work lies in the demonstration of experimental and theoretical techniques for precise control and modelling of complex quantum computers. In particular, we present a simple, parameter-free but predictive model of decoherence effects in our system.

  13. SHEEP AS AN EXPERIMENTAL MODEL FOR BIOMATERIAL IMPLANT EVALUATION

    PubMed Central

    SARTORETTO, SUELEN CRISTINA; UZEDA, MARCELO JOSÉ; MIGUEL, FÚLVIO BORGES; NASCIMENTO, JHONATHAN RAPHAELL; ASCOLI, FABIO; CALASANS-MAIA, MÔNICA DIUANA

    2016-01-01

    ABSTRACT Objective: Based on a literature review and on our own experience, this study proposes sheep as an experimental model to evaluate the bioactive capacity of bone substitute biomaterials, dental implant systems and orthopedics devices. The literature review covered relevant databases available on the Internet from 1990 until to date, and was supplemented by our own experience. Methods: For its resemblance in size and weight to humans, sheep are quite suitable for use as an experimental model. However, information about their utility as an experimental model is limited. The different stages involving sheep experiments were discussed, including the care during breeding and maintenance of the animals obtaining specimens for laboratory processing, and highlighting the unnecessary euthanasia of animals at the end of study, in accordance to the guidelines of the 3Rs Program. Results: All experiments have been completed without any complications regarding the animals and allowed us to evaluate hypotheses and explain their mechanisms. Conclusion: The sheep is an excellent animal model for evaluation of biomaterial for bone regeneration and dental implant osseointegration. From an ethical point of view, one sheep allows for up to 12 implants per animal, permitting to keep them alive at the end of the experiments. Level of Evidence II, Retrospective Study. PMID:28149193

  14. 48 CFR 852.215-71 - Evaluation factor commitments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Evaluation factor....215-71 Evaluation factor commitments. As prescribed in 815.304-71(b), insert the following clause: Evaluation Factor Commitments (DEC 2009) The offeror agrees, if awarded a contract, to use the service...

  15. Brain-derived neurotrophic factor reduces inflammation and hippocampal apoptosis in experimental Streptococcus pneumoniae meningitis.

    PubMed

    Xu, Danfeng; Lian, Di; Wu, Jing; Liu, Ying; Zhu, Mingjie; Sun, Jiaming; He, Dake; Li, Ling

    2017-08-04

    Streptococcus pneumoniae meningitis is a serious inflammatory disease of the central nervous system (CNS) and is associated with high morbidity and mortality rates. The inflammatory processes initiated by recognition of bacterial components contribute to apoptosis in the hippocampal dentate gyrus. Brain-derived neurotrophic factor (BDNF) has long been recommended for the treatment of CNS diseases due to its powerful neuro-survival properties, as well as its recently reported anti-inflammatory and anti-apoptotic effects in vitro and in vivo. In this study, we investigated the effects of BDNF-related signaling on the inflammatory response and hippocampal apoptosis in experimental models of pneumococcal meningitis. Pretreatment with exogenous BDNF or the tropomyosin-receptor kinase B (TrkB) inhibitor k252a was performed to assess the activation or inhibition of the BDNF/TrkB-signaling axis prior to intracisternal infection with live S. pneumoniae. At 24 h post-infection, rats were assessed for clinical severity and sacrificed to harvest the brains. Paraffin-embedded brain sections underwent hematoxylin and eosin staining to evaluate pathological severity, and cytokine and chemokine levels in the hippocampus and cortex were evaluated by enzyme-linked immunosorbent assay. Additionally, apoptotic neurons were detected in the hippocampal dentate gyrus by terminal deoxynucleotidyl transferase dUTP-nick-end labeling, key molecules associated with the related signaling pathway were analyzed by real-time polymerase chain reaction and western blot, and the DNA-binding activity of nuclear factor kappa B (NF-κB) was measured by electrophoretic mobility shift assay. Rats administered BDNF exhibited reduced clinical impairment, pathological severity, and hippocampal apoptosis. Furthermore, BDNF pretreatment suppressed the expression of inflammatory factors, including tumor necrosis factor α, interleukin (IL)-1β, and IL-6, and increased the expression of the anti

  16. Experimental and simulation studies of multivariable adaptive optimization of continuous bioreactors using bilevel forgetting factors.

    PubMed

    Chang, Y K; Lim, H C

    1989-08-20

    A multivariable on-line adaptive optimization algorithm using a bilevel forgetting factor method was developed and applied to a continuous baker's yeast culture in simulation and experimental studies to maximize the cellular productivity by manipulating the dilution rate and the temperature. The algorithm showed a good optimization speed and a good adaptability and reoptimization capability. The algorithm was able to stably maintain the process around the optimum point for an extended period of time. Two cases were investigated: an unconstrained and a constrained optimization. In the constrained optimization the ethanol concentration was used as an index for the baking quality of yeast cells. An equality constraint with a quadratic penalty was imposed on the ethanol concentration to keep its level close to a hypothetical "optimum" value. The developed algorithm was experimentally applied to a baker's yeast culture to demonstrate its validity. Only unconstrained optimization was carried out experimentally. A set of tuning parameter values was suggested after evaluating the results from several experimental runs. With those tuning parameter values the optimization took 50-90 h. At the attained steady state the dilution rate was 0.310 h(-1) the temperature 32.8 degrees C, and the cellular productivity 1.50 g/L/h.

  17. Fourth Meeting of the Panel for Evaluation of Experimental Literacy Projects. Final Report.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Paris (France).

    The work of this Panel for the Evaluation of Experimental Literacy Projects was the assessing of how the pattern of evaluation it had previously formulated had been applied in the Experimental World Literacy Programme (EWLP). In the judgment of the Panel, by 1974 evaluation specialists will be able to present a report that will enable Member…

  18. Experimental Evaluation of the Training Structure of the Picture Exchange Communication System (PECS)

    ERIC Educational Resources Information Center

    Cummings, Anne R.; Carr, James E.; LeBlanc, Linda A.

    2012-01-01

    The Picture Exchange Communication System (PECS) is a picture-based alternative communication method that is widely accepted and utilized with individuals with disabilities. Although prior studies have examined the clinical efficacy of PECS, none have experimentally evaluated its manualized training structure. We experimentally evaluated the…

  19. An Analytical Hierarchy Process Model for the Evaluation of College Experimental Teaching Quality

    ERIC Educational Resources Information Center

    Yin, Qingli

    2013-01-01

    Taking into account the characteristics of college experimental teaching, through investigaton and analysis, evaluation indices and an Analytical Hierarchy Process (AHP) model of experimental teaching quality have been established following the analytical hierarchy process method, and the evaluation indices have been given reasonable weights. An…

  20. Evaluation of an Experimental Adhesive Resin for Orthodontic Bonding

    NASA Astrophysics Data System (ADS)

    Durgesh, B. H.; Alkheraif, A. A.; Pavithra, D.; Hashem, M. I.; Alkhudhairy, F.; Elsharawy, M.; Divakar, D. D.; Vallittu, P. K.; Matinlinna, J. P.

    2017-07-01

    The aim of this study was to evaluate in vitro the effect of an experimental adhesive resin for orthodontic bonding by measuring some the chemical and mechanical properties. The resin demonstrated increased values of nanohardness and elastic modulus, but the differences were not significant compared with those for the Transbond XT adhesives. The experimental adhesive resin could be a feasible choice or a substitute for the traditional bis-GMA-based resins used in bonding orthodontic attachments.

  1. Evaluation of experimental rumble strips : 1982-1986 : final report.

    DOT National Transportation Integrated Search

    1987-07-01

    This report was prepared to provide the results of evaluations conducted upon twenty-six roadways where rumble strips were installed experimentally in Louisiana between August 1982 and September 1984. Situated randomly throughout Louisiana, construct...

  2. Evaluation of Cardiovascular Risk Factors in the Wistar Audiogenic Rat (WAR) Strain

    PubMed Central

    Fazan, Rubens; Silva, Carlos Alberto A.; Oliveira, José Antônio Cortes; Salgado, Helio Cesar; Montano, Nicola; Garcia-Cairasco, Norberto

    2015-01-01

    Introduction Risk factors for life-threatening cardiovascular events were evaluated in an experimental model of epilepsy, the Wistar Audiogenic Rat (WAR) strain. Methods We used long-term ECG recordings in conscious, one year old, WAR and Wistar control counterparts to evaluate spontaneous arrhythmias and heart rate variability, a tool to assess autonomic cardiac control. Ventricular function was also evaluated using the pressure-volume conductance system in anesthetized rats. Results Basal RR interval (RRi) was similar between WAR and Wistar rats (188±5 vs 199±6 ms). RRi variability strongly suggests that WAR present an autonomic imbalance with sympathetic overactivity, which is an isolated risk factor for cardiovascular events. Anesthetized WAR showed lower arterial pressure (92±3 vs 115±5 mmHg) and exhibited indices of systolic dysfunction, such as higher ventricle end-diastolic pressure (9.2±0.6 vs 5.6±1 mmHg) and volume (137±9 vs 68±9 μL) as well as lower rate of increase in ventricular pressure (5266±602 vs 7320±538 mmHg.s-1). Indices of diastolic cardiac function, such as lower rate of decrease in ventricular pressure (-5014±780 vs -7766±998 mmHg.s-1) and a higher slope of the linear relationship between end-diastolic pressure and volume (0.078±0.011 vs 0.036±0.011 mmHg.μL), were also found in WAR as compared to Wistar control rats. Moreover, Wistar rats had 3 to 6 ventricular ectopic beats, whereas WAR showed 15 to 30 ectopic beats out of the 20,000 beats analyzed in each rat. Conclusions The autonomic imbalance observed previously at younger age is also present in aged WAR and, additionally, a cardiac dysfunction was also observed in the rats. These findings make this experimental model of epilepsy a valuable tool to study risk factors for cardiovascular events in epilepsy. PMID:26029918

  3. 48 CFR 215.370-2 - Evaluation factor.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Evaluation factor. 215.370..., DEPARTMENT OF DEFENSE CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Source Selection 215.370-2 Evaluation factor. In accordance with Section 819 of the National Defense Authorization Act for...

  4. Evaluation of B&W UO2/ThO2 VIII experimental core: criticality and thermal disadvantage factor analysis

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

    Carlo Parisi; Emanuele Negrenti

    2017-02-01

    In the framework of the OECD/NEA International Reactor Physics Experiment (IRPHE) Project, an evaluation of core VIII of the Babcock & Wilcox (B&W) Spectral Shift Control Reactor (SSCR) critical experiment program was performed. The SSCR concept, moderated and cooled by a variable mixture of heavy and light water, envisaged changing of the thermal neutron spectrum during the operation to encourage breeding and to sustain the core criticality. Core VIII contained 2188 fuel rods with 93% enriched UO2-ThO2 fuel in a moderator mixture of heavy and light water. The criticality experiment and measurements of the thermal disadvantage factor were evaluated.

  5. The Effectiveness of Tutorial Strategies: An Experimental Evaluation.

    ERIC Educational Resources Information Center

    Swanson, Judy H.

    The effectiveness of three tutorial strategies was evaluated by experimentally manipulating the strategies used in a 2 X 3 factorial design. Two tutors taught 48 college undergraduates a basic optics lesson about "how lenses work," using three instructional methods which varied the amount of tutor control. In the lecture condition, tutors assumed…

  6. Factor XIII as a modulator of plasma fibronectin alterations during experimental bacteremia.

    PubMed

    Kiener, J L; Cho, E; Saba, T M

    1986-11-01

    Fibronectin is found in plasma as well as in association with connective tissue and cell surfaces. Depletion of plasma fibronectin is often observed in septic trauma and burned patients, while experimental rats often manifest hyperfibronectinemia with sepsis. Since Factor XIII may influence the rate of clearance and deposition of plasma fibronectin into tissues, we evaluated the temporal changes in plasma fibronectin and plasma Factor XIII following bacteremia and RE blockade in rats in an attempt to understand the mechanism leading to elevation of fibronectin levels in bacteremic rats, which is distinct from that observed with RE blockade. Clearance of exogenously administered fibronectin after bacteremia was also determined. Rats received either saline, Pseudomonas aeruginosa (1 X 10(9) organisms), gelatinized RE test lipid emulsion (50 mg/100 gm B.W.), or emulsion followed by Pseudomonas. Plasma fibronectin and Factor XIII were determined at 0, 2, 24, and 48 hours post-blockade or bacteremia. At 24 and 48 hr following bacteremia alone or bacteremia after RE blockade, there was a significant elevation (p less than 0.05) of plasma fibronectin and a concomitant decrease (p less than 0.05) of plasma factor XIII activity. Extractable tissue fibronectin from liver and spleen was also increased at 24 and 48 hours following R.E. blockade plus bacteremia. In addition, the plasma clearance of human fibronectin was significantly prolonged (p less than 0.05) following bacterial challenge. Infusion of activated Factor XIII (20 units/rat) during a period of hyperfibronectinemia (908.0 +/- 55.1 micrograms/ml) resulted in a significant (p less than 0.05) decrease in plasma fibronectin (548.5 +/- 49.9 micrograms/ml) within 30 min. Thus Factor XIII deficiency in rats with bacteremia may contribute to the elevation in plasma fibronectin by altering kinetics associated with the clearance of fibronectin from the blood.

  7. 48 CFR 2415.304 - Evaluation factors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... assigned a numerical weight (except for pass-fail factors) which shall appear in the RFP. When using LPTA, each evaluation factor is applied on a “pass-fail” basis; numerical scores are not assigned. “Pass-fail...

  8. 48 CFR 2415.304 - Evaluation factors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... assigned a numerical weight (except for pass-fail factors) which shall appear in the RFP. When using LPTA, each evaluation factor is applied on a “pass-fail” basis; numerical scores are not assigned. “Pass-fail...

  9. 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.

  10. Experienced quality factors: qualitative evaluation approach to audiovisual quality

    NASA Astrophysics Data System (ADS)

    Jumisko-Pyykkö, Satu; Häkkinen, Jukka; Nyman, Göte

    2007-02-01

    Subjective evaluation is used to identify impairment factors of multimedia quality. The final quality is often formulated via quantitative experiments, but this approach has its constraints, as subject's quality interpretations, experiences and quality evaluation criteria are disregarded. To identify these quality evaluation factors, this study examined qualitatively the criteria participants used to evaluate audiovisual video quality. A semi-structured interview was conducted with 60 participants after a subjective audiovisual quality evaluation experiment. The assessment compared several, relatively low audio-video bitrate ratios with five different television contents on mobile device. In the analysis, methodological triangulation (grounded theory, Bayesian networks and correspondence analysis) was applied to approach the qualitative quality. The results showed that the most important evaluation criteria were the factors of visual quality, contents, factors of audio quality, usefulness - followability and audiovisual interaction. Several relations between the quality factors and the similarities between the contents were identified. As a research methodological recommendation, the focus on content and usage related factors need to be further examined to improve the quality evaluation experiments.

  11. Computerized optimization of radioimmunoassays for hCG and estradiol: an experimental evaluation

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

    Yanagishita, M.; Rodbard, D.

    1978-07-15

    The mathematical and statistical theory of radioimmunoassays (RIAs) has been used to develop a series of computer programs to optimize sensitivity or precision at any desired dose level for either equilibrium or nonequilibrium assays. These computer programs provide for the calculation of the equilibrium constants of association and binding capacities for antisera (parameters of Scatchard plots), the association and dissociation rate constants, and prediction of optimum concentration of labeled ligand and antibody and optimum incubation times for the assay. This paper presents an experimental evaluation of the use of these computer programs applied to RIAs for human chorionic gonadotropin (hCG)more » and estradiol. The experimental results are in reasonable semiquantitative agreement with the predictions of the computer simulations (usually within a factor of two) and thus partially validate the use of computer techniques to optimize RIAs that are reasonably well behaved, as in the case of the hCG and estradiol RIAs. Further, these programs can provide insights into the nature of the RIA system, e.g., the general nature of the sensitivity and precision surfaces. This facilitates empirical optimization of conditions.« less

  12. Experimental evaluation of a cruciform piezoelectric energy harvester

    NASA Astrophysics Data System (ADS)

    Tsuruta, Karina M.; Rade, Domingos A.; Finzi Neto, Roberto M.; Cavalini, Aldemir A.

    2016-10-01

    This paper describes the development and experimental evaluation of a particular type of piezoelectric energy harvester, composed of four aluminum cantilever blades to which piezoelectric patches are bonded, in such way that electric energy is generated when the blades undergo bending vibrations. Concentrated masses, whose values can be varied, are attached to the tips of the blades. Due to the geometric shape of the harvester, in which the four blades are oriented forming right angles, the harvester is named cruciform. As opposed to the large majority of previous works on the subject, in which harvesters are excited at their bases by prescribed acceleration, herein the harvester is connected to a vibrating structure excited by an imbalance force. Hence, the amount of harvested energy depends upon the dynamic interaction between the harvester and the host structure. Laboratory experiments were carried-out on a prototype connected to a tridimensional truss. The experimental setup includes a force generator consisting of an imbalanced disc driven by an electrical motor whose rotation is controlled electronically, a voltage rectifier circuit, and a battery charged with the harvested energy. After characterization of the dynamic behavior of the harvester and the host structure, both numerically and experimentally, the results of experiments are presented and discussed in terms of the voltage output of the piezoelectric transducers as function of the excitation frequency and the values of the tip masses. Also, the capacity of the harvester to charge a Lithium battery is evaluated.

  13. Experimental methodology for turbocompressor in-duct noise evaluation based on beamforming wave decomposition

    NASA Astrophysics Data System (ADS)

    Torregrosa, A. J.; Broatch, A.; Margot, X.; García-Tíscar, J.

    2016-08-01

    An experimental methodology is proposed to assess the noise emission of centrifugal turbocompressors like those of automotive turbochargers. A step-by-step procedure is detailed, starting from the theoretical considerations of sound measurement in flow ducts and examining specific experimental setup guidelines and signal processing routines. Special care is taken regarding some limiting factors that adversely affect the measuring of sound intensity in ducts, namely calibration, sensor placement and frequency ranges and restrictions. In order to provide illustrative examples of the proposed techniques and results, the methodology has been applied to the acoustic evaluation of a small automotive turbocharger in a flow bench. Samples of raw pressure spectra, decomposed pressure waves, calibration results, accurate surge characterization and final compressor noise maps and estimated spectrograms are provided. The analysis of selected frequency bands successfully shows how different, known noise phenomena of particular interest such as mid-frequency "whoosh noise" and low-frequency surge onset are correlated with operating conditions of the turbocharger. Comparison against external inlet orifice intensity measurements shows good correlation and improvement with respect to alternative wave decomposition techniques.

  14. Evaluation of induction motor performance using an electronic power factor controller

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The concept of reducing the losses in an induction motor by electronically controlling the time interval between the zero crossing of the applied voltage and the zero crossing of the armature current was evaluated. The effect on power losses and power factor of reducing the applied sinusoidal voltages below the rated value was investigated experimentally. The reduction in power losses was measured using an electronic controller designed and built at MSFC. Modifications to the MSFC controller are described as well as a manually controlled electronic device which does not require that the motor be wye connected and the neutral available. Possible energy savings are examined.

  15. 48 CFR 519.1202 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Evaluation factor or subfactor. 519.1202 Section 519.1202 Federal Acquisition Regulations System GENERAL SERVICES ADMINISTRATION... Evaluation factor or subfactor. ...

  16. 48 CFR 19.1202 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Evaluation factor or subfactor. 19.1202 Section 19.1202 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION... Evaluation factor or subfactor. ...

  17. Experimental and Analytical Evaluation of a Composite Honeycomb Deployable Energy Absorber

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Kellas, Sotiris; Horta, Lucas G.; Annett, Martin S.; Polanco, Michael A.; Littell, Justin D.; Fasanella, Edwin L.

    2011-01-01

    In 2006, the NASA Subsonic Rotary Wing Aeronautics Program sponsored the experimental and analytical evaluation of an externally deployable composite honeycomb structure that is designed to attenuate impact energy during helicopter crashes. The concept, which is designated the Deployable Energy Absorber (DEA), utilizes an expandable Kevlar honeycomb structure to dissipate kinetic energy through crushing. The DEA incorporates a unique flexible hinge design that allows the honeycomb to be packaged and stowed flat until needed for deployment. A variety of deployment options such as linear, radial, and/or hybrid methods can be used. Experimental evaluation of the DEA utilized a building block approach that included material characterization testing of its constituent, Kevlar -129 fabric/epoxy, and flexural testing of single hexagonal cells. In addition, the energy attenuation capabilities of the DEA were demonstrated through multi-cell component dynamic crush tests, and vertical drop tests of a composite fuselage section, retrofitted with DEA blocks, onto concrete, water, and soft soil. During each stage of the DEA evaluation process, finite element models of the test articles were developed and simulations were performed using the explicit, nonlinear transient dynamic finite element code, LS-DYNA. This report documents the results of the experimental evaluation that was conducted to assess the energy absorption capabilities of the DEA.

  18. Optimal experimental design in an epidermal growth factor receptor signalling and down-regulation model.

    PubMed

    Casey, F P; Baird, D; Feng, Q; Gutenkunst, R N; Waterfall, J J; Myers, C R; Brown, K S; Cerione, R A; Sethna, J P

    2007-05-01

    We apply the methods of optimal experimental design to a differential equation model for epidermal growth factor receptor signalling, trafficking and down-regulation. The model incorporates the role of a recently discovered protein complex made up of the E3 ubiquitin ligase, Cbl, the guanine exchange factor (GEF), Cool-1 (beta -Pix) and the Rho family G protein Cdc42. The complex has been suggested to be important in disrupting receptor down-regulation. We demonstrate that the model interactions can accurately reproduce the experimental observations, that they can be used to make predictions with accompanying uncertainties, and that we can apply ideas of optimal experimental design to suggest new experiments that reduce the uncertainty on unmeasurable components of the system.

  19. The evaluation of experimental data in fast range for n + 56Fe(n,inl)

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

    Qian, Jing; Herman, M.; Ge, Zhigang

    Iron is one of the five materials selected for evaluation within the pilot international evaluation project CIELO. Analysis of experimental data for n+ 56Fe reaction is the basis for constraining theoretical calculations and eventual creation of the evaluated file. The detail analysis was performed for inelastic cross sections of neutron induced reactions with 56Fe in the fast range up to 20 MeV where there are significant differences among the main evaluated libraries, mainly caused by the different inelastic scattering cross section measurements. Gamma-ray production cross sections provide a way to gain experimental information about the inelastic cross section. Large discrepanciesmore » between experimental data for the 847-keV gamma ray produced in the 56Fe(n,n 1'γ) reaction were analyzed. In addition, experimental data for elastic scattering cross section between 9.41~11 MeV were used to deduce the inelastic cross section from the unitarity constrain.« less

  20. The evaluation of experimental data in fast range for n + 56Fe(n,inl)

    DOE PAGES

    Qian, Jing; Herman, M.; Ge, Zhigang; ...

    2017-09-13

    Iron is one of the five materials selected for evaluation within the pilot international evaluation project CIELO. Analysis of experimental data for n+ 56Fe reaction is the basis for constraining theoretical calculations and eventual creation of the evaluated file. The detail analysis was performed for inelastic cross sections of neutron induced reactions with 56Fe in the fast range up to 20 MeV where there are significant differences among the main evaluated libraries, mainly caused by the different inelastic scattering cross section measurements. Gamma-ray production cross sections provide a way to gain experimental information about the inelastic cross section. Large discrepanciesmore » between experimental data for the 847-keV gamma ray produced in the 56Fe(n,n 1'γ) reaction were analyzed. In addition, experimental data for elastic scattering cross section between 9.41~11 MeV were used to deduce the inelastic cross section from the unitarity constrain.« less

  1. Experimental and theoretical investigations of the quality factor for n+p silicon solar cells

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

    Garlick, G.F.J.; Kachare, A.H.

    1980-01-01

    Many N/sup +/P silicon cells made with silicon from different growth techniques have current-voltage relations of the form: I.I/sub 0/ (exp(qV/AkT) - 1) where the quality factor A is non-integral, is >1 and shows a temperature dependence. The dark forward characteristics of such cells have been measured over a range of temperature and the behavior of the factor A derived from them. A new model is presented on the assumption of non-uniform distributions of recombination levels in the junction depletion layer. This model shows good agreement with experimental data. The cells investigated had evaporated top metallization and so the junctionmore » contamination giving the recombination levels is likely to be a result of junction diffusion and is not specific to the metallization processing. The model needs further development and evaluation in order to apply it to the illuminated cell behavior and also to include any effects of distributed sheet resistance in the N/sup +/ layer. 17 refs.« less

  2. Autotransfusion from experimental hemothorax: levels of coagulation factors.

    PubMed

    Napoli, V M; Symbas, P J; Vroon, D H; Symbas, P N

    1987-03-01

    The coagulation system was investigated in five dogs undergoing autotransfusion from experimental hemothorax. One fourth of the blood volume was bled into the pleural space, drained, and autotransfused. The hemothorax blood showed: very prolonged PT and PTT; very low platelets and fibrinogen; midly elevated FDP; very low coagulation factors VIII, and V; reduced XII, prothrombin, X, XI, and VII. Partial clotting, mild fibrinolysis, and fibrin deposition over the pulmonary pleura seemed to cause incoagulability of hemothorax blood. Post autotransfusion arterial blood showed: normal PT and PTT; 25% decrease in platelets, and 31% decrease in fibrinogen from baseline values. There was also an overall 20% reduction of fibrinogen from baseline values. There was also an overall 20% reduction of all clotting factors, but their levels remained above 50% activity. It was concluded that autotransfusion from a hemothorax of 25% the blood volume in dogs causes a mild loss of hemostatic components, but does not significantly compromise the clotting mechanism.

  3. Experimental evaluation of cooling efficiency of the high performance cooling device

    NASA Astrophysics Data System (ADS)

    Nemec, Patrik; Malcho, Milan

    2016-06-01

    This work deal with experimental evaluation of cooling efficiency of cooling device capable transfer high heat fluxes from electric elements to the surrounding. The work contain description of cooling device, working principle of cooling device, construction of cooling device. Experimental part describe the measuring method of device cooling efficiency evaluation. The work results are presented in graphic visualization of temperature dependence of the contact area surface between cooling device evaporator and electronic components on the loaded heat of electronic components in range from 250 to 740 W and temperature dependence of the loop thermosiphon condenser surface on the loaded heat of electronic components in range from 250 to 740 W.

  4. THE ROLE OF PREDISPOSING FACTORS IN EXPERIMENTAL FUNGUS INFECTIONS

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

    Sheldon, W.H.; Bauer, H.

    Among other factors, the influence of ionizing radiations on susceptibility to fungus diseases is reviewed. X irradiation singly or in combination with cortisone administration has been employed in the study of experimental fungus diseases, and it has been shown that total-body radiation enhaaced infection with Candida albicans, Blastomyces dermatididis, and Cryptococcus neoformans in mice. Enhanced susceptibility to fungus infections following radiation therapy has also been reported, the mechanism resulting in lowered host resistance being presumably the same as in other infections. (BBB)

  5. The bias of experimental design, including strain background, in the determination of critical Streptococcus suis serotype 2 virulence factors

    PubMed Central

    Auger, Jean-Philippe; Chuzeville, Sarah; Roy, David; Mathieu-Denoncourt, Annabelle; Xu, Jianguo; Grenier, Daniel

    2017-01-01

    Streptococcus suis serotype 2 is an important porcine bacterial pathogen and emerging zoonotic agent mainly responsible for sudden death, septic shock, and meningitis. However, serotype 2 strains are genotypically and phenotypically heterogeneous. Though a multitude of virulence factors have been described for S. suis serotype 2, the lack of a clear definition regarding which ones are truly “critical” has created inconsistencies that have only recently been highlighted. Herein, the involvement of two factors previously described as being critical for S. suis serotype 2 virulence, whether the dipeptidyl peptidase IV and autolysin, were evaluated with regards to different ascribed functions using prototype strains belonging to important sequence types. Results demonstrate a lack of reproducibility with previously published data. In fact, the role of the dipeptidyl peptidase IV and autolysin as critical virulence factors could not be confirmed. Though certain in vitro functions may be ascribed to these factors, their roles are not unique for S. suis, probably due to compensation by other factors. As such, variations and discrepancies in experimental design, including in vitro assays, cell lines, and animal models, are an important source of differences between results. Moreover, the use of different sequence types in this study demonstrates that the role attributed to a virulence factor may vary according to the S. suis serotype 2 strain background. Consequently, it is necessary to establish standard experimental designs according to the experiment and purpose in order to facilitate comparison between laboratories. Alongside, studies should include strains of diverse origins in order to prevent erroneous and biased conclusions that could affect future studies. PMID:28753679

  6. Adaptive neural network motion control of manipulators with experimental evaluations.

    PubMed

    Puga-Guzmán, S; Moreno-Valenzuela, J; Santibáñez, V

    2014-01-01

    A nonlinear proportional-derivative controller plus adaptive neuronal network compensation is proposed. With the aim of estimating the desired torque, a two-layer neural network is used. Then, adaptation laws for the neural network weights are derived. Asymptotic convergence of the position and velocity tracking errors is proven, while the neural network weights are shown to be uniformly bounded. The proposed scheme has been experimentally validated in real time. These experimental evaluations were carried in two different mechanical systems: a horizontal two degrees-of-freedom robot and a vertical one degree-of-freedom arm which is affected by the gravitational force. In each one of the two experimental set-ups, the proposed scheme was implemented without and with adaptive neural network compensation. Experimental results confirmed the tracking accuracy of the proposed adaptive neural network-based controller.

  7. Adaptive Neural Network Motion Control of Manipulators with Experimental Evaluations

    PubMed Central

    Puga-Guzmán, S.; Moreno-Valenzuela, J.; Santibáñez, V.

    2014-01-01

    A nonlinear proportional-derivative controller plus adaptive neuronal network compensation is proposed. With the aim of estimating the desired torque, a two-layer neural network is used. Then, adaptation laws for the neural network weights are derived. Asymptotic convergence of the position and velocity tracking errors is proven, while the neural network weights are shown to be uniformly bounded. The proposed scheme has been experimentally validated in real time. These experimental evaluations were carried in two different mechanical systems: a horizontal two degrees-of-freedom robot and a vertical one degree-of-freedom arm which is affected by the gravitational force. In each one of the two experimental set-ups, the proposed scheme was implemented without and with adaptive neural network compensation. Experimental results confirmed the tracking accuracy of the proposed adaptive neural network-based controller. PMID:24574910

  8. 48 CFR 2415.304 - Evaluation factors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... DEVELOPMENT CONTRACTING METHODS AND CONTRACTING TYPES CONTRACTING BY NEGOTIATION Source Selection 2415.304... assigned a numerical weight (except for pass-fail factors) which shall appear in the RFP. When using LPTA, each evaluation factor is applied on a “pass-fail” basis; numerical scores are not assigned. “Pass-fail...

  9. Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C

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

    Chadwick, M.B.; Blann, M.; Cox, L.

    1995-04-11

    A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements wheremore » they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A{le}and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV.« less

  10. EVALUATING THE IMPORTANCE OF FACTORS IN ANY GIVEN ORDER OF FACTORING.

    PubMed

    Humphreys, L G; Tucker, L R; Dachler, P

    1970-04-01

    A methodology has been described and illustrated for obtaining an evaluation of the importance of the factors in a particular order of factoring that does not require faotoring beyond that order. For example, one can estimate the intercorrelations of the original measures with the perturbations of the first-order factor held constant or, the reverse, estimate the contribution to the intercorrelations of the originral measures from the first-order factors alone. Similar operations are possible at higher orders.

  11. Evaluation of experimental railroad-highway grade crossings in Louisiana : final report : 1970-1985.

    DOT National Transportation Integrated Search

    1986-04-01

    This report concludes formal evaluation of forty-one experimental high-type railroad-highway grade crossings installed experimentally throughout Louisiana between 1970 and 1984. These crossings were composed of various of rubber, high-density polyeth...

  12. 48 CFR 1552.215-71 - Evaluation factors for award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... for technical acceptability evaluation: (c) Factors for past performance evaluation (optional): (End... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Evaluation factors for award. 1552.215-71 Section 1552.215-71 Federal Acquisition Regulations System ENVIRONMENTAL PROTECTION...

  13. Benchmark Evaluation of HTR-PROTEUS Pebble Bed Experimental Program

    DOE PAGES

    Bess, John D.; Montierth, Leland; Köberl, Oliver; ...

    2014-10-09

    Benchmark models were developed to evaluate 11 critical core configurations of the HTR-PROTEUS pebble bed experimental program. Various additional reactor physics measurements were performed as part of this program; currently only a total of 37 absorber rod worth measurements have been evaluated as acceptable benchmark experiments for Cores 4, 9, and 10. Dominant uncertainties in the experimental keff for all core configurations come from uncertainties in the ²³⁵U enrichment of the fuel, impurities in the moderator pebbles, and the density and impurity content of the radial reflector. Calculations of k eff with MCNP5 and ENDF/B-VII.0 neutron nuclear data aremore » greater than the benchmark values but within 1% and also within the 3σ uncertainty, except for Core 4, which is the only randomly packed pebble configuration. Repeated calculations of k eff with MCNP6.1 and ENDF/B-VII.1 are lower than the benchmark values and within 1% (~3σ) except for Cores 5 and 9, which calculate lower than the benchmark eigenvalues within 4σ. The primary difference between the two nuclear data libraries is the adjustment of the absorption cross section of graphite. Simulations of the absorber rod worth measurements are within 3σ of the benchmark experiment values. The complete benchmark evaluation details are available in the 2014 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments.« less

  14. 48 CFR 5215.605 - Evaluation factors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REGULATIONS CONTRACTING BY NEGOTIATION Source Selection 5215.605 Evaluation factors. (S-90)(1) When a cost... the proposed costs may be adjusted, for purposes of evaluation, based upon the results of the cost... minimally acceptable approach or a cost/benefit approach. When the quality desired is that necessary to meet...

  15. Factors affecting DSAEK graft lenticle adhesion: an in vitro experimental study.

    PubMed

    Vaddavalli, Pravin K; Diakonis, Vasilios F; Canto, Ana P; Kankariya, Vardhaman P; Pappuru, Rajeev R; Ruggeri, Marco; Banitt, Michael R; Kymionis, George D; Yoo, Sonia H

    2014-06-01

    The aim of this study was to evaluate different factors that affect Descemet stripping automated endothelial keratoplasty (DSAEK) donor graft lenticle adhesion to the recipient cornea. This experimental study included 10 eye bank recipient corneas and 10 donor DSAEK lenticles. Recipient corneas were mounted on an artificial anterior chamber (AC), whereas donor lenticles were placed beneath the host cornea. Using optical coherence tomography and imaging software, the interface gap (IG) between the donor and recipient cornea was quantified to evaluate the effect of variations in AC air fill pressure, AC air fill duration, corneal massage, and corneal venting incisions on DSAEK donor graft lenticle adhesion. Different intraocular pressures (IOP) under air for the same time intervals, do not significantly correlate with the IG; nevertheless, it was noticed that the IG decreases as the IOP increases. With respect to the magnitude of AC IOP, there was no statistically significant difference when comparing 10 mm Hg with 30 mm Hg and assessing IG (P = 0.4). Complete air-fluid exchange resulted in significantly higher IG when compared with AC air bubble of 10 and 30 mm Hg that was sustained for 1 hour (P < 0.05). Furthermore, corneal surface massage did not facilitate DSAEK graft adhesion (P = 0.59). Finally, paracentral venting incisions followed by interface fluid aspiration seemed to significantly decrease the IG (P = 0.014). Corneal venting incisions and higher AC IOP values seem to facilitate DSAEK donor graft lenticle adhesion to the recipient cornea.

  16. 48 CFR 815.304-70 - Evaluation factor commitments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SDVOSBs; (2) Use past performance in meeting SDVOSB subcontracting goals as a non-price evaluation factor... as an evaluation factor when competitively negotiating the award of contracts or task or delivery... competitively negotiating the award of contracts or task or delivery orders. (b) If an offeror proposes to use...

  17. An experimental and theoretical evaluation of increased thermal diffusivity phase change devices

    NASA Technical Reports Server (NTRS)

    White, S. P.; Golden, J. O.; Stermole, F. J.

    1972-01-01

    This study was to experimentally evaluate and mathematically model the performance of phase change thermal control devices containing high thermal conductivity metal matrices. Three aluminum honeycomb filters were evaluated at five different heat flux levels using n-oct-adecane as the test material. The system was mathematically modeled by approximating the partial differential equations with a three-dimensional implicit alternating direction technique. The mathematical model predicts the system quite well. All of the phase change times are predicted. The heating of solid phase is predicted exactly while there is some variation between theoretical and experimental results in the liquid phase. This variation in the liquid phase could be accounted for by the fact that there are some heat losses in the cell and there could be some convection in the experimental system.

  18. Experimental and environmental factors affect spurious detection of ecological thresholds

    USGS Publications Warehouse

    Daily, Jonathan P.; Hitt, Nathaniel P.; Smith, David; Snyder, Craig D.

    2012-01-01

    Threshold detection methods are increasingly popular for assessing nonlinear responses to environmental change, but their statistical performance remains poorly understood. We simulated linear change in stream benthic macroinvertebrate communities and evaluated the performance of commonly used threshold detection methods based on model fitting (piecewise quantile regression [PQR]), data partitioning (nonparametric change point analysis [NCPA]), and a hybrid approach (significant zero crossings [SiZer]). We demonstrated that false detection of ecological thresholds (type I errors) and inferences on threshold locations are influenced by sample size, rate of linear change, and frequency of observations across the environmental gradient (i.e., sample-environment distribution, SED). However, the relative importance of these factors varied among statistical methods and between inference types. False detection rates were influenced primarily by user-selected parameters for PQR (τ) and SiZer (bandwidth) and secondarily by sample size (for PQR) and SED (for SiZer). In contrast, the location of reported thresholds was influenced primarily by SED. Bootstrapped confidence intervals for NCPA threshold locations revealed strong correspondence to SED. We conclude that the choice of statistical methods for threshold detection should be matched to experimental and environmental constraints to minimize false detection rates and avoid spurious inferences regarding threshold location.

  19. Sexual Violence Prevention through Bystander Education: An Experimental Evaluation

    ERIC Educational Resources Information Center

    Banyard, Victoria L.; Moynihan, Mary M.; Plante, Elizabethe G.

    2007-01-01

    The current study used an experimental design to evaluate a sexual violence prevention program based on a community of responsibility model that teaches women and men how to intervene safely and effectively in cases of sexual violence before, during, and after incidents with strangers, acquaintances, or friends. It approaches both women and men as…

  20. Evaluation of experimental coating to improve the zirconia-veneering ceramic bond strength.

    PubMed

    Matani, Jay D; Kheur, Mohit; Jambhekar, Shantanu Subhashchandra; Bhargava, Parag; Londhe, Aditya

    2014-12-01

    To evaluate the shear bond strength (SBS) between zirconia and veneering ceramic following different surface treatments of zirconia. The efficacy of an experimental zirconia coating to improve the bond strength was also evaluated. Zirconia strips were fabricated and were divided into four groups as per their surface treatment: polished (control), airborne-particle abrasion, laser irradiation, and application of the experimental coating. The surface roughness and the residual monoclinic content were evaluated before and after the respective surface treatments. A scanning electron microscope (SEM) analysis of the experimental surfaces was performed. All specimens were subjected to shear force in a universal testing machine. The SBS values were analyzed with one-way ANOVA followed by Bonferroni post hoc for groupwise comparisons. The fractured specimens were examined to observe the failure mode. The SBS (29.17 MPa) and roughness values (0.80) of the experimental coating group were the highest among the groups. The residual monoclinic content was minimal (0.32) when compared to the remaining test groups. SEM analysis revealed a homogenous surface well adhered to an undamaged zirconia base. The other test groups showed destruction of the zirconia surface. The analysis of failure following bond strength testing showed entirely cohesive failures in the veneering ceramic in all study groups. The experimental zirconia surface coating is a simple technique to increase the microroughness of the zirconia surface, and thereby improve the SBS to the veneering ceramic. It results in the least monoclinic content and produces no structural damage to the zirconia substructure. © 2014 by the American College of Prosthodontists.

  1. Factors Associated with Evaluating Public Relations Activities.

    ERIC Educational Resources Information Center

    McElreath, Mark P.

    More than 150 public relations practitioners responded to a survey designed to identify and clarify factors associated with evaluative research in public relations. Responses indicated that (1) no more than half the practitioners formally evaluate their public relations activities on a regular basis; (2) the majority of evaluation is done…

  2. Experimental and analytical tools for evaluation of Stirling engine rod seal behavior

    NASA Technical Reports Server (NTRS)

    Krauter, A. I.; Cheng, H. S.

    1979-01-01

    The first year of a two year experimental and analytical program is reported. The program is directed at the elastohydrodynamic behavior of sliding elastomeric rod seals for the Stirling engine. During the year, experimental and analytical tools were developed for evaluating seal leakage, seal friction, and the fluid film thickness at the seal/cylinder interface.

  3. Experimental Study of Factors Affecting Soil Erodibility

    NASA Astrophysics Data System (ADS)

    Larionov, G. A.; Bushueva, O. G.; Gorobets, A. V.; Dobrovolskaya, N. G.; Kiryukhina, Z. P.; Krasnov, S. F.; Litvin, L. F.; Maksimova, I. A.; Sudnitsyn, I. I.

    2018-03-01

    The effect of different factors and preparation conditions of monofraction samples from the arable horizon of leached chernozem on soil erodibility and its relationship with soil tensile strength (STS) has been studied. The exposure of samples at 38°C reduces their erodibility by two orders of magnitude. The drying of samples, on the contrary, increases their erodibility. It has been shown that erodibility decreases during the experiment. It has been found that the inoculation of soil with yeast cultures ( Naganishia albida, Lipomyces tetrasporus) reliably increases the STS value in 1.5-1.9 times. The sterile soil is eroded more intensively than the unsterile soil: at 4.9 and 0.3 g/(m2 s), respectively. The drying of soil followed by wetting to the initial water content (30%) has no significant effect on the STS value in almost all experimental treatments.

  4. Using factorial experimental design to evaluate the separation of plastics by froth flotation.

    PubMed

    Salerno, Davide; Jordão, Helga; La Marca, Floriana; Carvalho, M Teresa

    2018-03-01

    This paper proposes the use of factorial experimental design as a standard experimental method in the application of froth flotation to plastic separation instead of the commonly used OVAT method (manipulation of one variable at a time). Furthermore, as is common practice in minerals flotation, the parameters of the kinetic model were used as process responses rather than the recovery of plastics in the separation products. To explain and illustrate the proposed methodology, a set of 32 experimental tests was performed using mixtures of two polymers with approximately the same density, PVC and PS (with mineral charges), with particle size ranging from 2 to 4 mm. The manipulated variables were frother concentration, air flow rate and pH. A three-level full factorial design was conducted. The models establishing the relationships between the manipulated variables and their interactions with the responses (first order kinetic model parameters) were built. The Corrected Akaike Information Criterion was used to select the best fit model and an analysis of variance (ANOVA) was conducted to identify the statistically significant terms of the model. It was shown that froth flotation can be used to efficiently separate PVC from PS with mineral charges by reducing the floatability of PVC, which largely depends on the action of pH. Within the tested interval, this is the factor that most affects the flotation rate constants. The results obtained show that the pure error may be of the same magnitude as the sum of squares of the errors, suggesting that there is significant variability within the same experimental conditions. Thus, special care is needed when evaluating and generalizing the process. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Evaluation of the 235U prompt fission neutron spectrum including a detailed analysis of experimental data and improved model information

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

    Neudecker, Denise; Talou, Patrick; Kahler, Albert Comstock III

    We present an evaluation of the 235U prompt fission neutron spectrum (PFNS) induced by thermal to 20-MeV neutrons. Experimental data and associated covariances were analyzed in detail. The incident energy dependence of the PFNS was modeled with an extended Los Alamos model combined with the Hauser-Feshbach and the exciton models. These models describe prompt fission, pre-fission compound nucleus and pre-equilibrium neutron emissions. The evaluated PFNS agree well with the experimental data included in this evaluation, preliminary data of the LANL and LLNL Chi-Nu measurement and recent evaluations by Capote et al. and Rising et al. However, they are softer thanmore » the ENDF/B-VII.1 (VII.1) and JENDL-4.0 PFNS for incident neutron energies up to 2 MeV. Simulated effective multiplication factors k eff of the Godiva and Flattop-25 critical assemblies are further from the measured k eff if the current data are used within VII.1 compared to using only VII.1 data. However, if this work is used with ENDF/B-VIII.0β2 data, simulated values of k eff agree well with the measured ones.« less

  6. Evaluation of the 235U prompt fission neutron spectrum including a detailed analysis of experimental data and improved model information

    DOE PAGES

    Neudecker, Denise; Talou, Patrick; Kahler, Albert Comstock III; ...

    2017-09-13

    We present an evaluation of the 235U prompt fission neutron spectrum (PFNS) induced by thermal to 20-MeV neutrons. Experimental data and associated covariances were analyzed in detail. The incident energy dependence of the PFNS was modeled with an extended Los Alamos model combined with the Hauser-Feshbach and the exciton models. These models describe prompt fission, pre-fission compound nucleus and pre-equilibrium neutron emissions. The evaluated PFNS agree well with the experimental data included in this evaluation, preliminary data of the LANL and LLNL Chi-Nu measurement and recent evaluations by Capote et al. and Rising et al. However, they are softer thanmore » the ENDF/B-VII.1 (VII.1) and JENDL-4.0 PFNS for incident neutron energies up to 2 MeV. Simulated effective multiplication factors k eff of the Godiva and Flattop-25 critical assemblies are further from the measured k eff if the current data are used within VII.1 compared to using only VII.1 data. However, if this work is used with ENDF/B-VIII.0β2 data, simulated values of k eff agree well with the measured ones.« less

  7. Evaluation of the 235U prompt fission neutron spectrum including a detailed analysis of experimental data and improved model information

    NASA Astrophysics Data System (ADS)

    Neudecker, Denise; Talou, Patrick; Kahler, Albert C.; White, Morgan C.; Kawano, Toshihiko

    2017-09-01

    We present an evaluation of the 235U prompt fission neutron spectrum (PFNS) induced by thermal to 20-MeV neutrons. Experimental data and associated covariances were analyzed in detail. The incident energy dependence of the PFNS was modeled with an extended Los Alamos model combined with the Hauser-Feshbach and the exciton models. These models describe prompt fission, pre-fission compound nucleus and pre-equilibrium neutron emissions. The evaluated PFNS agree well with the experimental data included in this evaluation, preliminary data of the LANL and LLNL Chi-Nu measurement and recent evaluations by Capote et al. and Rising et al. However, they are softer than the ENDF/B-VII.1 (VII.1) and JENDL-4.0 PFNS for incident neutron energies up to 2 MeV. Simulated effective multiplication factors keff of the Godiva and Flattop-25 critical assemblies are further from the measured keff if the current data are used within VII.1 compared to using only VII.1 data. However, if this work is used with ENDF/B-VIII.0β2 data, simulated values of keff agree well with the measured ones.

  8. Effect of experimental and sample factors on dehydration kinetics of mildronate dihydrate: mechanism of dehydration and determination of kinetic parameters.

    PubMed

    Bērziņš, Agris; Actiņš, Andris

    2014-06-01

    The dehydration kinetics of mildronate dihydrate [3-(1,1,1-trimethylhydrazin-1-ium-2-yl)propionate dihydrate] was analyzed in isothermal and nonisothermal modes. The particle size, sample preparation and storage, sample weight, nitrogen flow rate, relative humidity, and sample history were varied in order to evaluate the effect of these factors and to more accurately interpret the data obtained from such analysis. It was determined that comparable kinetic parameters can be obtained in both isothermal and nonisothermal mode. However, dehydration activation energy values obtained in nonisothermal mode showed variation with conversion degree because of different rate-limiting step energy at higher temperature. Moreover, carrying out experiments in this mode required consideration of additional experimental complications. Our study of the different sample and experimental factor effect revealed information about changes of the dehydration rate-limiting step energy, variable contribution from different rate limiting steps, as well as clarified the dehydration mechanism. Procedures for convenient and fast determination of dehydration kinetic parameters were offered. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  9. The Development of Experimentation and Evidence Evaluation Skills at Preschool Age

    NASA Astrophysics Data System (ADS)

    Piekny, Jeanette; Grube, Dietmar; Maehler, Claudia

    2014-01-01

    Researchers taking a domain-general approach to the development of scientific reasoning long thought that the ability to engage in scientific reasoning did not develop until adolescence. However, more recent studies have shown that preschool children already have a basic ability to evaluate evidence and a basic understanding of experimentation. Data providing insights into when exactly in the preschool years significant gains in these abilities occur are scarce. Drawing on a sample of 138 preschool children, this longitudinal study therefore examined how children's ability to evaluate evidence and their understanding of experimentation develop between the ages of four and six. Findings showed that the ability to evaluate evidence was already well developed at age four and increased steadily and significantly over time as long as the pattern of covariation was perfect. In the case of imperfect covariation, the proportion of correct answers was low over the period of observation, but showed a significant increase between the ages of four and five. If the data did not allow relationship between variables to be inferred, the proportion of correct answers was low, with a significant increase between the ages of five and six. The children's understanding of experimentation increased significantly between the ages of five and six. The implications of these findings for age-appropriate science programs in preschool are discussed.

  10. 48 CFR 2015.304 - Evaluation factors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Source Selection Processes and Techniques 2015.304... numerically weighted are conflict of interest, estimated cost, and “go/no go” evaluation factors. ...

  11. Experimental Evaluation of Family Curriculum Materials for High School Students.

    ERIC Educational Resources Information Center

    Angrist, Shirley S.; And Others

    This paper describes two new family life curriculum development projects at Carnegie-Mellon University and presents the results of an evaluation of two mini-courses using a modified Solomon four-group experimental design. Based on historical, sociological, anthropological, and psychological research, the first unit presents family life in Japan…

  12. Leveraging Volunteers: An Experimental Evaluation of a Tutoring Program for Struggling Readers

    ERIC Educational Resources Information Center

    Jacob, Robin; Armstrong, Catherine; Bowden, A. Brooks; Pan, Yilin

    2016-01-01

    This study evaluates the impacts and costs of the Reading Partners program, which uses community volunteers to provide one-on-one tutoring to struggling readers in under-resourced elementary schools. The evaluation uses an experimental design. Students were randomly assigned within 19 different Reading Partners sites to a program or control…

  13. Examining dynamic interactions among experimental factors influencing hydrologic data assimilation with the ensemble Kalman filter

    NASA Astrophysics Data System (ADS)

    Wang, S.; Huang, G. H.; Baetz, B. W.; Cai, X. M.; Ancell, B. C.; Fan, Y. R.

    2017-11-01

    The ensemble Kalman filter (EnKF) is recognized as a powerful data assimilation technique that generates an ensemble of model variables through stochastic perturbations of forcing data and observations. However, relatively little guidance exists with regard to the proper specification of the magnitude of the perturbation and the ensemble size, posing a significant challenge in optimally implementing the EnKF. This paper presents a robust data assimilation system (RDAS), in which a multi-factorial design of the EnKF experiments is first proposed for hydrologic ensemble predictions. A multi-way analysis of variance is then used to examine potential interactions among factors affecting the EnKF experiments, achieving optimality of the RDAS with maximized performance of hydrologic predictions. The RDAS is applied to the Xiangxi River watershed which is the most representative watershed in China's Three Gorges Reservoir region to demonstrate its validity and applicability. Results reveal that the pairwise interaction between perturbed precipitation and streamflow observations has the most significant impact on the performance of the EnKF system, and their interactions vary dynamically across different settings of the ensemble size and the evapotranspiration perturbation. In addition, the interactions among experimental factors vary greatly in magnitude and direction depending on different statistical metrics for model evaluation including the Nash-Sutcliffe efficiency and the Box-Cox transformed root-mean-square error. It is thus necessary to test various evaluation metrics in order to enhance the robustness of hydrologic prediction systems.

  14. Evaluation of New Reference Genes in Papaya for Accurate Transcript Normalization under Different Experimental Conditions

    PubMed Central

    Chen, Weixin; Chen, Jianye; Lu, Wangjin; Chen, Lei; Fu, Danwen

    2012-01-01

    Real-time reverse transcription PCR (RT-qPCR) is a preferred method for rapid and accurate quantification of gene expression studies. Appropriate application of RT-qPCR requires accurate normalization though the use of reference genes. As no single reference gene is universally suitable for all experiments, thus reference gene(s) validation under different experimental conditions is crucial for RT-qPCR analysis. To date, only a few studies on reference genes have been done in other plants but none in papaya. In the present work, we selected 21 candidate reference genes, and evaluated their expression stability in 246 papaya fruit samples using three algorithms, geNorm, NormFinder and RefFinder. The samples consisted of 13 sets collected under different experimental conditions, including various tissues, different storage temperatures, different cultivars, developmental stages, postharvest ripening, modified atmosphere packaging, 1-methylcyclopropene (1-MCP) treatment, hot water treatment, biotic stress and hormone treatment. Our results demonstrated that expression stability varied greatly between reference genes and that different suitable reference gene(s) or combination of reference genes for normalization should be validated according to the experimental conditions. In general, the internal reference genes EIF (Eukaryotic initiation factor 4A), TBP1 (TATA binding protein 1) and TBP2 (TATA binding protein 2) genes had a good performance under most experimental conditions, whereas the most widely present used reference genes, ACTIN (Actin 2), 18S rRNA (18S ribosomal RNA) and GAPDH (Glyceraldehyde-3-phosphate dehydrogenase) were not suitable in many experimental conditions. In addition, two commonly used programs, geNorm and Normfinder, were proved sufficient for the validation. This work provides the first systematic analysis for the selection of superior reference genes for accurate transcript normalization in papaya under different experimental conditions. PMID

  15. Some factors influencing the nonexpert's perception and evaluation of environmental risks

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

    Vaughan, E.

    Policy makers and decision analysts have been limited somewhat in their ability to predict public reactions to regulatory decisions about hazardous substances or technologies. Most studies of the nonexpert's evaluation of environmental risks have relied on survey data and correlational analyses which preclude the determination of interactive effects, effects that could explain apparent inconsistencies. Three experimental studies were designed to test empirically the effect of six dimensions of environmental risk on judgments of (1) perceived risk, (2) acceptability of risk, (3) subjective probability of negative outcomes due to exposure, and (4) perceived severity of consequences. Factors examined included: (a) familiaritymore » with the terms used to describe a hazard, (b) environmental persistence of a chemical, (c) personal relevance of data used to evaluate cancer-causing potential, (d) personal relevance of possible adverse consequences, (e) perceived control over exposure, and (f) vividness of the exposure pathway. The findings were discussed in terms of their implications for the nonexpert's formulation of risk perceptions, and public policy in the domain of environmental risks.« less

  16. A Formative-Summative Evaluation Design for a State-Sponsored Program of Educational Experimentation.

    ERIC Educational Resources Information Center

    Kniefel, Tanya M.

    An evaluation design created to provide information for a multiple-project program of educational experimentation is presented. Project SEED (State Experimentation in Educational Development) became an official education effort in North Carolina on July 1, 1971. Model for the program was that of the State's ESEA Title III program with certain…

  17. 48 CFR 514.270-3 - Evaluation factors for award.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Evaluation factors for award. 514.270-3 Section 514.270-3 Federal Acquisition Regulations System GENERAL SERVICES... factors for award. The solicitation should clearly state the basis for evaluating bids for aggregate award...

  18. Classroom Factors Affecting Students: Self-Evaluation: An Interactional Model.

    ERIC Educational Resources Information Center

    Marshall, Hermine H.; Weinstein, Rhona S.

    1984-01-01

    A complex interactional model of classroom factors that contribute to the development of students' self-evaluations is presented. Factors described are: (1) task structure; (2) grouping practices; (3) feedback and evaluation procedures and information about ability; (4) motivational strategies; (5) locus of responsibility for learning; and (6) the…

  19. SuperLab LT: Evaluation and Uses in Teaching Experimental Psychology

    ERIC Educational Resources Information Center

    Ragozzine, Frank

    2002-01-01

    I describe and evaluate SuperLab LT (Chase & Abboud, 1990), a software package that enables students to replicate classic experiments in cognitive psychology. I also discuss the package with respect to its uses in teaching an undergraduate course in Experimental Psychology. Although the package has minor flaws, SuperLab LT provides numerous…

  20. Exogenous factors matter when interpreting the results of an impact evaluation: a case study of rainfall and child health programme intervention in Rwanda.

    PubMed

    Mukabutera, Assumpta; Thomson, Dana R; Hedt-Gauthier, Bethany L; Atwood, Sidney; Basinga, Paulin; Nyirazinyoye, Laetitia; Savage, Kevin P; Habimana, Marcellin; Murray, Megan

    2017-12-01

    Public health interventions are often implemented at large scale, and their evaluation seems to be difficult because they are usually multiple and their pathways to effect are complex and subject to modification by contextual factors. We assessed whether controlling for rainfall-related variables altered estimates of the efficacy of a health programme in rural Rwanda and have a quantifiable effect on an intervention evaluation outcomes. We conducted a retrospective quasi-experimental study using previously collected cross-sectional data from the 2005 and 2010 Rwanda Demographic and Health Surveys (DHS), 2010 DHS oversampled data, monthly rainfall data collected from meteorological stations over the same period, and modelled output of long-term rainfall averages, soil moisture, and rain water run-off. Difference-in-difference models were used. Rainfall factors confounded the PIH intervention impact evaluation. When we adjusted our estimates of programme effect by controlling for a variety of rainfall variables, several effectiveness estimates changed by 10% or more. The analyses that did not adjust for rainfall-related variables underestimated the intervention effect on the prevalence of ARI by 14.3%, fever by 52.4% and stunting by 10.2%. Conversely, the unadjusted analysis overestimated the intervention's effect on diarrhoea by 56.5% and wasting by 80%. Rainfall-related patterns have a quantifiable effect on programme evaluation results and highlighted the importance and complexity of controlling for contextual factors in quasi-experimental design evaluations. © 2017 John Wiley & Sons Ltd.

  1. An experimental evaluation of the REE SIFT environment for spaceborne applications

    NASA Technical Reports Server (NTRS)

    Whistnant, K.; Iyer, R. K.; Jones, P.; Some, R.; Rennels, D.

    2002-01-01

    This paper presents an experimental evaluation of a software-implemented fault tolerance environment built around a set of self-checking ARMOR proceses running on different machines that provide error detection and recovery services to themselves and to spaceborne scientific applications.

  2. An analytical and experimental evaluation of a Fresnel lens solar concentrator

    NASA Technical Reports Server (NTRS)

    Hastings, L. J.; Allums, S. A.; Cosby, R. M.

    1976-01-01

    An analytical and experimental evaluation of line focusing Fresnel lenses with application potential in the 200 to 370 C range was studied. Analytical techniques were formulated to assess the solar transmission and imaging properties of a grooves down lens. Experimentation was based on a 56 cm wide, f/1.0 lens. A Sun tracking heliostat provided a nonmoving solar source. Measured data indicated more spreading at the profile base than analytically predicted, resulting in a peak concentration 18 percent lower than the computed peak of 57. The measured and computed transmittances were 85 and 87 percent, respectively. Preliminary testing with a subsequent lens indicated that modified manufacturing techniques corrected the profile spreading problem and should enable improved analytical experimental correlation.

  3. [Evaluation of Contextual Factors in Psychosomatic Rehabilitation].

    PubMed

    Bülau, N I; Kessemeier, F; Petermann, F; Bassler, M; Kobelt, A

    2016-12-01

    Objectives: Although individualized and ICF-oriented implementation of rehabilitation treatment requires knowledge of relevant contextual factors, there is a lack of operationalized documentation and measurement tools to evaluate these factors. Therefore, an ICF-oriented semi-structured interview was designed. Methods: 20 contextual factors were externally assessed whether they negatively affected mental functioning and participation of psychosomatic patients. Additionally, psychometric scales were applied. Results: Six relevant impairing contextual factors were identified. Contextual factors significantly correlated with psychometric scales. Patients with higher contextual impairment showed significantly higher psychological stress levels. Conclusions: Anamnesis of contextual factors at the beginning of psychosomatic rehabilitation yields important information for therapy planning. Further research on contextual factors in medical rehabilitation is needed. © Georg Thieme Verlag KG Stuttgart · New York.

  4. IMPROVED EXPERIMENTAL MODEL TO EVALUATE SUBMUCOSAL INJECTION SOLUTIONS FOR ENDOSCOPIC SUBMUCOSAL DISSECTION.

    PubMed

    Yamazaki, Kendi; Maluf-Filho, Fauze; da Costa, Vitor Alves Pessoa; Pessorrusso, Fernanda Cristina Simões; Hondo, Fabio Yuji; Sakai, Paulo; de Figueiredo, Luis Francisco Poli

    2015-01-01

    Endoscopic submucosal dissection carries an increased risk of bleeding and perforation. The creation of a long lasting submucosal cushion is essential for the safe and complete removal of the lesion. There is not a suitable experimental model for evaluation of the durability of the cushioning effect of different solutions. To describe an improved experimental model to evaluate submucosal injection solutions. A total of four domestic pigs were employed to evaluate two different submucosal fluid solutions in the gastric submucosa. After midline laparotomy, the anterior gastric wall was incised from the gastric body to the antrum and its mucosal surface was exposed by flipping inside out the incised gastric wall. Two different solutions (10% mannitol and normal saline) were injected in the submucosa of the anterior wall of the distal gastric body. All submucosal cushions were injected until they reach the same size, standardized as 1.0 cm in height and 2.0 cm in diameter. A caliper and a ruler were employed to guarantee accuracy of the measurements. All four animal experiments were completed. All submucosal cushions had the exact same size measured with caliper and a ruler. By using the mannitol solution, the mean duration of the submucosal cushion was longer than the saline solution: 20 and 22 min (mean, 21 min) vs 5 and 6 min (mean, 5.5 min) This experimental model is simple and evaluate the duration, size, and effect of the submucosal cushion, making it more reliable than other models that employ resected porcine stomachs or endoscopic images in live porcine models.

  5. Experimental Myocardial Infarction Upregulates Circulating Fibroblast Growth Factor-23.

    PubMed

    Andrukhova, Olena; Slavic, Svetlana; Odörfer, Kathrin I; Erben, Reinhold G

    2015-10-01

    Myocardial infarction (MI) is a major cause of death worldwide. Epidemiological studies have linked vitamin D deficiency to MI incidence. Because fibroblast growth factor-23 (FGF23) is a master regulator of vitamin D hormone production and has been shown to be associated with cardiac hypertrophy per se, we explored the hypothesis that FGF23 may be a previously unrecognized pathophysiological factor causally linked to progression of cardiac dysfunction post-MI. Here, we show that circulating intact Fgf23 was profoundly elevated, whereas serum vitamin D hormone levels were suppressed, after induction of experimental MI in rat and mouse models, independent of changes in serum soluble Klotho or serum parathyroid hormone. Both skeletal and cardiac expression of Fgf23 was increased after MI. Although the molecular link between the cardiac lesion and circulating Fgf23 concentrations remains to be identified, our study has uncovered a novel heart-bone-kidney axis that may have important clinical implications and may inaugurate the new field of cardio-osteology. © 2015 American Society for Bone and Mineral Research.

  6. Of taps and toilets: quasi-experimental protocol for evaluating community-demand-driven projects.

    PubMed

    Pattanayak, Subhrendu K; Poulos, Christine; Yang, Jui-Chen; Patil, Sumeet R; Wendland, Kelly J

    2009-09-01

    Sustainable and equitable access to safe water and adequate sanitation are widely acknowledged as vital, yet neglected, development goals. Water supply and sanitation (WSS) policies are justified because of the usual efficiency criteria, but also major equity concerns. Yet, to date there are few scientific impact evaluations showing that WSS policies are effective in delivering social welfare outcomes. This lack of an evaluation culture is partly because WSS policies are characterized by diverse mechanisms, broad goals and the increasing importance of decentralized delivery, and partly because programme administrators are unaware of appropriate methods. We describe a protocol for a quasi-experimental evaluation of a community-demand-driven programme for water and sanitation in rural India, which addresses several evaluation challenges. After briefly reviewing policy and implementation issues in the sector, we describe key features of our protocol, including control group identification, pre-post measurement, programme theory, sample sufficiency and robust indicators. At its core, our protocol proposes to combine propensity score matching and difference-in-difference estimation. We conclude by briefly summarizing how quasi-experimental impact evaluations can address key issues in WSS policy design and when such evaluations are needed.

  7. Experimentation and evaluation of advanced integrated system concepts

    NASA Astrophysics Data System (ADS)

    Ross, M.; Garrigus, K.; Gottschalck, J.; Rinearson, L.; Longee, E.

    1980-09-01

    This final report examines the implementation of a time-phased test bed for experimentation and evaluation of advanced system concepts relative to the future Defense Switched Network (DSN). After identifying issues pertinent to the DSN, a set of experiments which address these issues are developed. Experiments are ordered based on their immediacy and relative importance to DSN development. The set of experiments thus defined allows requirements for a time phased implementation of a test bed to be identified, and several generic test bed architectures which meet these requirements are examined. Specific architecture implementations are costed and cost/schedule profiles are generated as a function of experimental capability. The final recommended system consists of two separate test beds: a circuit switch test bed, configured around an off-the-shelf commercial switch, and directed toward the examination of nearer term and transitional issues raised by the evolving DSN; and a packet/hybrid test bed, featuring a discrete buildup of new hardware and software modules, and directed toward examination of the more advanced integrated voice and data telecommunications issues and concepts.

  8. Experimental evaluation of a translating nozzle sidewall radial turbine

    NASA Technical Reports Server (NTRS)

    Roelke, Richard J.; Rogo, Casimir

    1987-01-01

    Studies have shown that reduced specific fuel consumption of rotorcraft engines can be achieved with a variable capacity engine. A key component in such an engine in a high-work, high-temperature variable geometry gas generator turbine. An optimization study indicated that a radial turbine with a translating nozzle sidewall could produce high efficiency over a wide range of engine flows but substantiating data were not available. An experimental program with Teledyne CAE, Toledo, Ohio was undertaken to evaluate the moving sidewall concept. A variety of translating nozzle sidewall turbine configurations were evaluated. The effects of nozzle leakage and coolant flows were also investigated. Testing was done in warm air (121 C). The results of the contractual program were summarized.

  9. An Experimental Test of Factors Attracting Deer Mice into Buildings.

    PubMed

    Kuenzi, Amy J; Douglass, Richard

    2009-09-01

    Deer mice (Peromyscus maniculatus) are the principal reservoir host of Sin Nombre virus (SNV). Deer mice use a wide variety of habitats including peridomestic settings in and around human dwellings, their presence in and around homes has been implicated as a risk factor for acquiring Hantavirus Pulmonary Syndrome. Deer mice are believed to enter buildings in order to gain access to a variety of resources including food, bedding material, and better thermal microclimates. However, no one has experimentally tested which factors influence mice use of buildings. We conducted experiments using small simulated buildings to determine the effects of two factors, i.e., food and bedding material, on mouse activity in these buildings. We also examined if these effects varied with time of year. We found that deer mice entered our buildings regardless of the presence or absence of food or bedding. However, the amount of activity in buildings was affected by what they contained. We found significantly higher indices of activity in buildings containing food compared to both empty buildings (control) and buildings containing bedding material. Time of year did not affect activity in buildings.

  10. Evaluating E-Training for Public Library Staff: A Quasi-Experimental Investigation

    ERIC Educational Resources Information Center

    Dalston, Teresa

    2009-01-01

    A comparative evaluation framework of instructional interventions for implementation of online training for public library staff would enable a better understanding of how to improve the effectiveness, efficiency and efficacy of training in certain training environments. This dissertation describes a quasi-experimental study of a two-week,…

  11. Experimental evaluation of theoretical sea surface reflectance factors relevant to above-water radiometry.

    PubMed

    Zibordi, Giuseppe

    2016-03-21

    Determination of the water-leaving radiance LW through above-water radiometry requires knowledge of accurate reflectance factors ρ of the sea surface. Publicly available ρ relevant to above-water radiometry include theoretical data sets generated: i. by assuming a sky radiance distribution accounting for aerosols and multiple scattering, but neglecting polarization, and quantifying sea surface effects through Cox-Munk wave slope statistics; or differently ii. accounting for polarization, but assuming an ideal Rayleigh sky radiance distribution, and quantifying sea surface effects through modeled wave elevation and slope variance spectra. The impact on above-water data products of differences between those factors ρ was quantified through comparison of LW from the Ocean Color component of the Aerosol Robotic Network (AERONET-OC) with collocated LW from in-water radiometry. Results from the analysis of radiance measurements from the sea performed with 40 degrees viewing angle and 90 degrees azimuth offset with respect to the sun plane, indicated a slightly better agreement between above- and in-water LW determined for wind speeds tentatively lower than 4 m s-1 with ρ computed accounting for aerosols, multiple scattering and Cox-Munk surfaces. Nevertheless, analyses performed by partitioning the investigated data set also indicated that actual ρ values would exhibit dependence on sun zenith comprised between those characterizing the two sets of reflectance factors.

  12. IMPROVED EXPERIMENTAL MODEL TO EVALUATE SUBMUCOSAL INJECTION SOLUTIONS FOR ENDOSCOPIC SUBMUCOSAL DISSECTION

    PubMed Central

    YAMAZAKI, Kendi; MALUF-FILHO, Fauze; da COSTA, Vitor Alves Pessoa; PESSORRUSSO, Fernanda Cristina Simões; HONDO, Fabio Yuji; SAKAI, Paulo; de FIGUEIREDO, Luis Francisco Poli

    2015-01-01

    Background : Endoscopic submucosal dissection carries an increased risk of bleeding and perforation. The creation of a long lasting submucosal cushion is essential for the safe and complete removal of the lesion. There is not a suitable experimental model for evaluation of the durability of the cushioning effect of different solutions. Aim : To describe an improved experimental model to evaluate submucosal injection solutions. Methods : A total of four domestic pigs were employed to evaluate two different submucosal fluid solutions in the gastric submucosa. After midline laparotomy, the anterior gastric wall was incised from the gastric body to the antrum and its mucosal surface was exposed by flipping inside out the incised gastric wall. Two different solutions (10% mannitol and normal saline) were injected in the submucosa of the anterior wall of the distal gastric body. All submucosal cushions were injected until they reach the same size, standardized as 1.0 cm in height and 2.0 cm in diameter. A caliper and a ruler were employed to guarantee accuracy of the measurements. Results : All four animal experiments were completed. All submucosal cushions had the exact same size measured with caliper and a ruler. By using the mannitol solution, the mean duration of the submucosal cushion was longer than the saline solution: 20 and 22 min (mean, 21 min) vs 5 and 6 min (mean, 5.5 min) Conclusions : This experimental model is simple and evaluate the duration, size, and effect of the submucosal cushion, making it more reliable than other models that employ resected porcine stomachs or endoscopic images in live porcine models. PMID:26734797

  13. Experimental Evaluation of a Structure-Based Connectionist Network for Fault Diagnosis of Helicopter Gearboxes

    NASA Technical Reports Server (NTRS)

    Jammu, V. B.; Danai, K.; Lewicki, D. G.

    1998-01-01

    This paper presents the experimental evaluation of the Structure-Based Connectionist Network (SBCN) fault diagnostic system introduced in the preceding article. For this vibration data from two different helicopter gearboxes: OH-58A and S-61, are used. A salient feature of SBCN is its reliance on the knowledge of the gearbox structure and the type of features obtained from processed vibration signals as a substitute to training. To formulate this knowledge, approximate vibration transfer models are developed for the two gearboxes and utilized to derive the connection weights representing the influence of component faults on vibration features. The validity of the structural influences is evaluated by comparing them with those obtained from experimental RMS values. These influences are also evaluated ba comparing them with the weights of a connectionist network trained though supervised learning. The results indicate general agreement between the modeled and experimentally obtained influences. The vibration data from the two gearboxes are also used to evaluate the performance of SBCN in fault diagnosis. The diagnostic results indicate that the SBCN is effective in directing the presence of faults and isolating them within gearbox subsystems based on structural influences, but its performance is not as good in isolating faulty components, mainly due to lack of appropriate vibration features.

  14. An Evaluation of the Effects of Experimenter Control of Objects on Individuals' Engagement in Object Stereotypy

    ERIC Educational Resources Information Center

    Stangeland, Lindsay A.; Smith, Dean P.; Rapp, John T.

    2012-01-01

    In two experiments, the authors evaluated the extent to which (a) individuals preferred engaging in object stereotypy versus observing an experimenter while the experimenter engaged in object stereotypy and (b) an experimenter's engagement in object stereotypy decreased the participants' engagement in object stereotypy. Results of Experiment 1…

  15. Experimental evaluation of sensorimotor patterning used with mentally retarded children.

    PubMed

    Neman, R; Roos, P; McCann, R M; Menolascino, F J; Heal, L W

    1975-01-01

    In the present study, a sensorimotor "patterning" program used with 66 institutionalized, mentally retarded children and adolescents was evaluated. The subjects were randomly assigned to one of three groups: (a) Experimental 1 group, which received a program of mobility exercises including patterning, creeping, and crawling; visual-motor training; and sensory stimulation exercises; (b) Experimental 2 group, which received a program of physical activity, personal attention, and the same sensory stimulation program given to the first group; or (c) Passive Control group, which provided baseline measures but which received no additional programming as part of the study. Experimental 1 group subjects improved more than subjects in the other groups in visual perception, program-related measures of mobility, and language ability. Intellectual functioning did not appear to be enhanced by the procedures, at least during the active phase of the project. The results were discussed with reference to other researchers who have failed to support the patterning approach, and some reasons were suggested for the differences between the present and past investigations.

  16. Experimental Design for Evaluating the Safety Benefits of Railroad Advance Warning Signs

    DOT National Transportation Integrated Search

    1979-04-01

    The report presents the findings and conclusions of a study to develop an experimental design and analysis plan for field testing and evaluation of the accident reduction potential of a proposed new railroad grade crossing advance warning sign. Sever...

  17. Factors Underlying the Public's Credibility Perceptions in Educational Evaluations

    ERIC Educational Resources Information Center

    Jacobson, Miriam R.

    2016-01-01

    Understanding how evaluation audiences perceive credibility can help evaluators design evaluations and reports that support appropriate use. While researchers have studied credibility assessment among various educational stakeholders, little research has been conducted with the broader public. This study explored potential factors affecting the…

  18. A modified F-test for evaluating model performance by including both experimental and simulation uncertainties

    USDA-ARS?s Scientific Manuscript database

    Experimental and simulation uncertainties have not been included in many of the statistics used in assessing agricultural model performance. The objectives of this study were to develop an F-test that can be used to evaluate model performance considering experimental and simulation uncertainties, an...

  19. Experimental Keratitis Due to Pseudomonas aeruginosa: Model for Evaluation of Antimicrobial Drugs

    PubMed Central

    Davis, Starkey D.; Chandler, John W.

    1975-01-01

    An improved method for experimental keratitis due to Pseudomonas aeruginosa is described. Essential features of the method are use of inbred guinea pigs, intracorneal injection of bacteria, subconjunctival injection of antibiotics, “blind” evaluation of results, and statistical analysis of data. Untreated ocular infections were most severe 5 to 7 days after infection. Sterilized bacterial suspensions caused no abnormalities on day 5. Tobramycin and polymyxin B were more active than gentamicin against two strains of Pseudomonas. This model is suitable for many types of quantitative studies on experimental keratitis. Images PMID:810084

  20. Experimental Support for Evaluation of the Victoria Class Virtual Submarine (VCVS)

    DTIC Science & Technology

    2012-03-01

    comportementales de ce genre . y A P P R O V A L S H E E T Document No. 5283-001 Version 03 Document Name: Experimental Support for Evaluation...encountered that reduced access to HMCS Corner Brook: 11  Cold moves to charge submarine batteries;  Filming events; and,  Slight delays due

  1. Determination of Ensemble-Average Pairwise Root Mean-Square Deviation from Experimental B-Factors

    PubMed Central

    Kuzmanic, Antonija; Zagrovic, Bojan

    2010-01-01

    Abstract Root mean-square deviation (RMSD) after roto-translational least-squares fitting is a measure of global structural similarity of macromolecules used commonly. On the other hand, experimental x-ray B-factors are used frequently to study local structural heterogeneity and dynamics in macromolecules by providing direct information about root mean-square fluctuations (RMSF) that can also be calculated from molecular dynamics simulations. We provide a mathematical derivation showing that, given a set of conservative assumptions, a root mean-square ensemble-average of an all-against-all distribution of pairwise RMSD for a single molecular species, 1/2, is directly related to average B-factors () and 1/2. We show this relationship and explore its limits of validity on a heterogeneous ensemble of structures taken from molecular dynamics simulations of villin headpiece generated using distributed-computing techniques and the Folding@Home cluster. Our results provide a basis for quantifying global structural diversity of macromolecules in crystals directly from x-ray experiments, and we show this on a large set of structures taken from the Protein Data Bank. In particular, we show that the ensemble-average pairwise backbone RMSD for a microscopic ensemble underlying a typical protein x-ray structure is ∼1.1 Å, under the assumption that the principal contribution to experimental B-factors is conformational variability. PMID:20197040

  2. Effects of Nuclear Factor-E2-related factor 2/Heme Oxygenase 1 on splanchnic hemodynamics in experimental cirrhosis with portal hypertension.

    PubMed

    Qin, Jun; He, Yue; Duan, Ming; Luo, Meng

    2017-05-01

    We explored the effects of Nuclear Factor-E2-related factor 2 (Nrf2) and Heme Oxygenase 1 (HO-1) on splanchnic hemodynamics in portal hypertensive rats. Experimental cirrhosis with portal hypertension was induced by intraperitoneal injection of carbon tetrachloride. The expression of proteins was examined by immunoblotting. Hemodynamic studies were performed by radioactive microspheres. The vascular perfusion system was used to measure the contractile response of mesentery arterioles in rats. Nrf2 expression in the nucleus and HO-1 expression in cytoplasm was significantly enhanced in portal hypertensive rats. Portal pressure, as well as regional blood flow, increased significantly in portal hypertension and can be blocked by tin protoporphyrin IX. The expression of endogenous nitric oxide synthase and vascular endothelial growth factors increased significantly compared to normal rats, while HO-1 inhibition decreased the expression of these proteins significantly. The contractile response of mesenteric arteries decreased in portal hypertension, but can be partially recovered through tin protoporphyrin IX treatment. The expression of Nrf2/HO-1 increased in mesenteric arteries of portal hypertensive rats, which was related to oxidative stress. HO-1was involved in increased portal pressure and anomaly splanchnic hemodynamics in portal hypertensive rats. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Evaluation of True Power Luminous Efficiency from Experimental Luminance Values

    NASA Astrophysics Data System (ADS)

    Tsutsui, Tetsuo; Yamamato, Kounosuke

    1999-05-01

    A method for obtaining true external power luminous efficiencyfrom experimentally obtained luminance in organic light-emittingdiodes (LEDs) wasdemonstrated. Conventional two-layer organic LEDs with different electron-transport layer thicknesses wereprepared. Spatial distributions of emission intensities wereobserved. The large deviation in both emission spectra and spatialemission patterns were observed when the electron-transport layerthickness was varied. The deviation of emission patterns from thestandard Lambertian pattern was found to cause overestimations ofpower luminous efficiencies as large as 30%. A method for evaluatingcorrection factors was proposed.

  4. Unique considerations in the design and experimental evaluation of tailored wings with elastically produced chordwise camber

    NASA Technical Reports Server (NTRS)

    Rehfield, Lawrence W.; Zischka, Peter J.; Fentress, Michael L.; Chang, Stephen

    1992-01-01

    Some of the unique considerations that are associated with the design and experimental evaluation of chordwise deformable wing structures are addressed. Since chordwise elastic camber deformations are desired and must be free to develop, traditional rib concepts and experimental methodology cannot be used. New rib design concepts are presented and discussed. An experimental methodology based upon the use of a flexible sling support and load application system has been created and utilized to evaluate a model box beam experimentally. Experimental data correlate extremely well with design analysis predictions based upon a beam model for the global properties of camber compliance and spanwise bending compliance. Local strain measurements exhibit trends in agreement with intuition and theory but depart slightly from theoretical perfection based upon beam-like behavior alone. It is conjectured that some additional refinement of experimental technique is needed to explain or eliminate these (minor) departures from asymmetric behavior of upper and lower box cover strains. Overall, a solid basis for the design of box structures based upon the bending method of elastic camber production has been confirmed by the experiments.

  5. Simulated and experimental evaluation of factors affecting the rate and extent of reductive dehalogenation of chloroethenes with glucose.

    PubMed

    Lee, Il-Su; Bae, Jae-Ho; Yang, Yanru; McCarty, Perry L

    2004-10-01

    Carbohydrates such as molasses are being added to aquifers to serve as electron donors for reductive dehalogenation of chloroethenes. Glucose, as a model carbohydrate, was studied to better understand the processes involved and to evaluate the effectiveness for dehalogenation of different approaches for carbohydrate addition. A simulation model was developed and calibrated with experimental data for the reductive dehalogenation of tetrachloroethene to ethene via cis-1,2-dichloroethene. The model included fermentors that convert the primary donor (glucose) into butyrate, acetate and hydrogen, methanogens, and two separate dehalogenator groups. The dehalogenation groups use the hydrogen intermediate as an electron donor and the different haloethenes as electron acceptors through competitive inhibition. Model simulations suggest first that the initial relative population size of dehalogenators and H(2)-utilizing methanogens greatly affects the degree of dehalogenation achieved. Second, the growth and decay of biomass from soluble carbohydrate plays a significant role in reductive dehalogenation. Finally, the carbohydrate delivery strategies used (periodic versus batch addition and the time interval between periodic addition) greatly affect the degree of dehalogenation that can be obtained with a given amount of added carbohydrate.

  6. Multi-function displays : a guide for human factors evaluation.

    DOT National Transportation Integrated Search

    2013-11-01

    This guide is designed to assist aircraft certification personnel and avionics : manufacturers in evaluating the human factors aspects of Multi-function Displays : (MFDs) for FAA certification. The guide focuses specifically on human factors and : do...

  7. A key role for Pre-B cell colony-enhancing factor in experimental hepatitis.

    PubMed

    Moschen, Alexander R; Gerner, Romana; Schroll, Andrea; Fritz, Teresa; Kaser, Arthur; Tilg, Herbert

    2011-08-01

    Pre-B cell colony-enhancing factor (PBEF), also known as nicotinamide phosphoribosyltransferase or visfatin, plays an important role in metabolic, inflammatory, and malignant diseases. Recent evidence suggests that blocking its enzymatic activity using a specific small-molecule inhibitor (FK866) might be beneficial in acute experimental inflammation. We investigated the role of PBEF in human liver disease and experimental hepatitis. PBEF serum levels and hepatic expression were determined in patients with chronic liver diseases. These studies were followed by in vivo experiments using concanavalin A (ConA) and D-galactosamine/lipopolysaccharide (LPS) models of experimental hepatitis. PBEF was either overexpressed by hydrodynamic perfusion or inhibited by FK866. In vivo findings were corroborated studying inflammatory responses of lentivirally PBEF-silenced or control FL83B mouse hepatocytes. Here, we demonstrate that PBEF serum levels were increased in patients with chronic liver diseases irrespective of disease stage and etiology. In particular, we observed enhanced PBEF expression in hepatocytes. Liver-targeted overexpression of PBEF rendered mice more susceptible to ConA- and D-galactosamine/LPS-induced hepatitis compared with control animals. In contrast, inhibition of PBEF using FK866 protected mice from ConA-induced liver damage and apoptosis. Administration of FK866 resulted in depletion of liver nicotinamide adenine dinucleotide+ levels and reduced proinflammatory cytokine expression. Additionally, FK866 protected mice in the D-galactosamine/LPS model of acute hepatitis. In vitro, PBEF-silenced mouse hepatocytes showed decreased responses after stimulation with LPS, lipoteichoic acid, and tumor necrosis factor α. In primary murine Kupffer cells, FK866 suppressed LPS-induced interleukin (IL)-6 production, whereas incubation with recombinant PBEF resulted in increased IL-6 release. Our data suggest that PBEF is of key importance in experimental hepatitis

  8. Radiological and histopathological evaluation of experimentally-induced periapical lesion in rats

    PubMed Central

    TEIXEIRA, Renata Cordeiro; RUBIRA, Cassia Maria Fischer; ASSIS, Gerson Francisco; LAURIS, José Roberto Pereira; CESTARI, Tania Mary; RUBIRA-BULLEN, Izabel Regina Fischer

    2011-01-01

    Objective This study evaluated experimentally-induced periapical bone loss sites using digital radiographic and histopathologic parameters. Material and Methods Twenty-seven Wistar rats were submitted to coronal opening of their mandibular right first molars. They were radiographed at 2, 15 and 30 days after the operative procedure by two digital radiographic storage phosphor plates (Digora®). The images were analyzed by creating a region of interest at the periapical region of each tooth (ImageJ) and registering the corresponding pixel values. After the sacrifice, the specimens were submitted to microscopic analysis in order to confirm the pulpal and periapical status of the tooth. Results There was significant statistically difference between the control and test sides in all the experimental periods regarding the pixel values (two-way ANOVA; p<0.05). Conclusions The microscopic analysis proved that a periapical disease development occurred during the experimental periods with an evolution from pulpal necrosis to periapical bone resorption. PMID:21922123

  9. Experimental Evaluation of the Effects of a Research-Based Preschool Mathematics Curriculum

    ERIC Educational Resources Information Center

    Clements, Douglas H.; Sarama, Julie

    2008-01-01

    A randomized-trials design was used to evaluate the effectiveness of a preschool mathematics program based on a comprehensive model of research-based curricula development. Thirty-six preschool classrooms were assigned to experimental (Building Blocks), comparison (a different preschool mathematics curriculum), or control conditions. Children were…

  10. Determination of ensemble-average pairwise root mean-square deviation from experimental B-factors.

    PubMed

    Kuzmanic, Antonija; Zagrovic, Bojan

    2010-03-03

    Root mean-square deviation (RMSD) after roto-translational least-squares fitting is a measure of global structural similarity of macromolecules used commonly. On the other hand, experimental x-ray B-factors are used frequently to study local structural heterogeneity and dynamics in macromolecules by providing direct information about root mean-square fluctuations (RMSF) that can also be calculated from molecular dynamics simulations. We provide a mathematical derivation showing that, given a set of conservative assumptions, a root mean-square ensemble-average of an all-against-all distribution of pairwise RMSD for a single molecular species, (1/2), is directly related to average B-factors () and (1/2). We show this relationship and explore its limits of validity on a heterogeneous ensemble of structures taken from molecular dynamics simulations of villin headpiece generated using distributed-computing techniques and the Folding@Home cluster. Our results provide a basis for quantifying global structural diversity of macromolecules in crystals directly from x-ray experiments, and we show this on a large set of structures taken from the Protein Data Bank. In particular, we show that the ensemble-average pairwise backbone RMSD for a microscopic ensemble underlying a typical protein x-ray structure is approximately 1.1 A, under the assumption that the principal contribution to experimental B-factors is conformational variability. 2010 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  11. Factors associated with experimentation of electronic cigarettes among Parisian teenagers in 2013.

    PubMed

    Dautzenberg, Bertrand; Berlin, Ivan; Tanguy, Marie-Laure; Rieu, Nicole; Birkui, Pierre

    2015-01-01

    Electronic cigarettes (e-cig.) became widely used among adults. Data are insufficient about e-cig. experimentation among youth. To assess prevalence of e-cig. experimentation and associated factors among the 12 to 19 years old we analyse a cross sectional school based survey in the city of Paris, France in 2013 on a randomly selected sample of 2 % of schoolchildren (n = 3 279). Self-report questionnaire include demographic, individual and family smoking characteristics and questions about e-cig: "Have you ever used an e-cigarette?"- "Did you use e-cigarette in the last 30 days?"-"Did you try e-cigarette as a first tobacco product?". In 2013, 17.9 % (564) schoolchildren reported having experienced the e-cig (boys: 19.0 %, girls: 16.8 %) compared to 9.8 % in 2012. Experimentation rate increases from 5 % among the 12 to 30 % among the 16-year-old. E-cig. experimentation was significantly associated with 11 parameters including : age >15 years (OR: 0.66 (IC95 % = 0.46-0.94)); smoking 10 cigarettes or more (OR = 5.67 (IC95 % = 3.11-10.34)), best friends and siblings smoker (OR = 1.54 (IC95 % = 1.11-2.14)) and (OR = 1.88 (IC95 % = 1.41-2.52)); experimentation of shisha (OR = 2.60 (IC95 % = 1.75-3.86)), cannabis use (OR = 1.90 (IC95 % = 1.32-2.72)); having two parents who forbid smoking (OR = 2.32 (IC95 % = 1.63-3.30)). Only 5.6 % of the study population (and 32.5 % of e-cig. experimenters (183/564)) have used it in the last 30 days; 1.7 % of the study population and 10.0 % of e-cig. experimenters were non-smokers (56/564). Rate of e-cig. experimentation among schoolchildren increased by 8.1 % in 1 year. Non-smoking youth may use e-cig. Prospective studies are urgently needed to assess the evolution of e-cig. use both among smoking and non-smoking youth.

  12. Experimental validation of beam quality correction factors for proton beams

    NASA Astrophysics Data System (ADS)

    Gomà, Carles; Hofstetter-Boillat, Bénédicte; Safai, Sairos; Vörös, Sándor

    2015-04-01

    This paper presents a method to experimentally validate the beam quality correction factors (kQ) tabulated in IAEA TRS-398 for proton beams and to determine the kQ of non-tabulated ionization chambers (based on the already tabulated values). The method is based exclusively on ionometry and it consists in comparing the reading of two ionization chambers under the same reference conditions in a proton beam quality Q and a reference beam quality 60Co. This allows one to experimentally determine the ratio between the kQ of the two ionization chambers. In this work, 7 different ionization chamber models were irradiated under the IAEA TRS-398 reference conditions for 60Co beams and proton beams. For the latter, the reference conditions for both modulated beams (spread-out Bragg peak field) and monoenergetic beams (pseudo-monoenergetic field) were studied. For monoenergetic beams, it was found that the experimental kQ values obtained for plane-parallel chambers are consistent with the values tabulated in IAEA TRS-398; whereas the kQ values obtained for cylindrical chambers are not consistent—being higher than the tabulated values. These results support the suggestion (of previous publications) that the IAEA TRS-398 reference conditions for monoenergetic proton beams should be revised so that the effective point of measurement of cylindrical ionization chambers is taken into account when positioning the reference point of the chamber at the reference depth. For modulated proton beams, the tabulated kQ values of all the ionization chambers studied in this work were found to be consistent with each other—except for the IBA FC65-G, whose experimental kQ value was found to be 0.6% lower than the tabulated one. The kQ of the PTW Advanced Markus chamber, which is not tabulated in IAEA TRS-398, was found to be 0.997 ± 0.042 (k = 2), based on the tabulated value of the PTW Markus chamber.

  13. Evaluation of experimental railroad-highway grade crossings in Louisiana : interim report No. 5.

    DOT National Transportation Integrated Search

    1980-04-01

    This interim report is prepared to provide a review of the performance evaluation exhibited on twenty-three (23) experimental railroad-highway grade-crossing projects in the state of Louisiana. The railroad crossings were installed during a ten-year ...

  14. Evaluating psychological interventions in a novel experimental human model of anxiety

    PubMed Central

    Ainsworth, Ben; Marshall, Jemma E.; Meron, Daniel; Baldwin, David S.; Chadwick, Paul; Munafò, Marcus R.; Garner, Matthew

    2015-01-01

    Inhalation of 7.5% carbon dioxide increases anxiety and autonomic arousal and provides a novel experimental model of anxiety with which to evaluate pharmacological and psychological treatments for anxiety. To date several psychotropic drugs including benzodiazepines, SSRIs and SNRIs have been evaluated using the 7.5% CO2 model; however, it has yet to be used to evaluate psychological interventions. We compared the effects of two core psychological components of mindfulness-meditation (open monitoring and focused attention) against general relaxation, on subjective, autonomic and neuropsychological outcomes in the 7.5% CO2 experimental model. 32 healthy screened adults were randomized to complete 10 min of guided open monitoring, focused attention or relaxation, immediately before inhaling 7.5% CO2 for 20 min. During CO2-challenge participants completed an eye-tracking measure of attention control and selective attention. Measures of subjective anxiety, blood pressure and heart rate were taken at baseline and immediately following intervention and CO2-challenge. OM and FA practice reduced subjective feelings of anxiety during 20-min inhalation of 7.5% CO2 compared to relaxation control. OM practice produced a strong anxiolytic effect, whereas the effect of FA was more modest. Anxiolytic OM and FA effects occurred in the absence of group differences in autonomic arousal and eye-movement measures of attention. Our findings are consistent with neuropsychological models of mindfulness-meditation that propose OM and FA activate prefrontal mechanisms that support emotion regulation during periods of anxiety and physiological hyper-arousal. Our findings complement those from pharmacological treatment studies, further supporting the use of CO2 challenge to evaluate future therapeutic interventions for anxiety. PMID:25765144

  15. Evaluating the Madrasa Preschool Programme in East Africa: A Quasi-Experimental Study

    ERIC Educational Resources Information Center

    Mwaura, Peter A. M.; Sylva, Kathy; Malmberg, Lars-Erik

    2008-01-01

    This study investigated the effect of preschool experience (two types of preschool: Madrasa and non-Madrasa) on the cognitive development of children in East Africa. In the three countries studied (Kenya, Uganda, and Tanzania/Zanzibar) preschool education is burgeoning and government standards are being set. This quasi experimental evaluation used…

  16. An Experimental Analysis of the Relation between Assigned Grades and Instructor Evaluations

    ERIC Educational Resources Information Center

    Smith, Dale L.; Cook, Patrick; Buskist, William

    2011-01-01

    The perceived relation between assigned student grades and instructor evaluations of teaching has been the subject of much debate, though few laboratory studies have been conducted with adequate controls. Marsh and Roche suggested that experimental field studies may be a particularly promising avenue for further analyses of this relation. The…

  17. Experimental Adiabatic Quantum Factorization under Ambient Conditions Based on a Solid-State Single Spin System.

    PubMed

    Xu, Kebiao; Xie, Tianyu; Li, Zhaokai; Xu, Xiangkun; Wang, Mengqi; Ye, Xiangyu; Kong, Fei; Geng, Jianpei; Duan, Changkui; Shi, Fazhan; Du, Jiangfeng

    2017-03-31

    The adiabatic quantum computation is a universal and robust method of quantum computing. In this architecture, the problem can be solved by adiabatically evolving the quantum processor from the ground state of a simple initial Hamiltonian to that of a final one, which encodes the solution of the problem. Adiabatic quantum computation has been proved to be a compatible candidate for scalable quantum computation. In this Letter, we report on the experimental realization of an adiabatic quantum algorithm on a single solid spin system under ambient conditions. All elements of adiabatic quantum computation, including initial state preparation, adiabatic evolution (simulated by optimal control), and final state read-out, are realized experimentally. As an example, we found the ground state of the problem Hamiltonian S_{z}I_{z} on our adiabatic quantum processor, which can be mapped to the factorization of 35 into its prime factors 5 and 7.

  18. Experimental Adiabatic Quantum Factorization under Ambient Conditions Based on a Solid-State Single Spin System

    NASA Astrophysics Data System (ADS)

    Xu, Kebiao; Xie, Tianyu; Li, Zhaokai; Xu, Xiangkun; Wang, Mengqi; Ye, Xiangyu; Kong, Fei; Geng, Jianpei; Duan, Changkui; Shi, Fazhan; Du, Jiangfeng

    2017-03-01

    The adiabatic quantum computation is a universal and robust method of quantum computing. In this architecture, the problem can be solved by adiabatically evolving the quantum processor from the ground state of a simple initial Hamiltonian to that of a final one, which encodes the solution of the problem. Adiabatic quantum computation has been proved to be a compatible candidate for scalable quantum computation. In this Letter, we report on the experimental realization of an adiabatic quantum algorithm on a single solid spin system under ambient conditions. All elements of adiabatic quantum computation, including initial state preparation, adiabatic evolution (simulated by optimal control), and final state read-out, are realized experimentally. As an example, we found the ground state of the problem Hamiltonian SzIz on our adiabatic quantum processor, which can be mapped to the factorization of 35 into its prime factors 5 and 7.

  19. Human Factors Evaluations of Two-Dimensional Spacecraft Conceptual Layouts

    NASA Technical Reports Server (NTRS)

    Kennedy, Kriss J.; Toups, Larry D.; Rudisill, Marianne

    2010-01-01

    Much of the human factors work done in support of the NASA Constellation lunar program has been with low fidelity mockups. These volumetric replicas of the future lunar spacecraft allow researchers to insert test subjects from the engineering and astronaut population and evaluate the vehicle design as the test subjects perform simulations of various operational tasks. However, lunar outpost designs must be evaluated without the use of mockups, creating a need for evaluation tools that can be performed on two-dimension conceptual spacecraft layouts, such as floor plans. A tool based on the Cooper- Harper scale was developed and applied to one lunar scenario, enabling engineers to select between two competing floor plan layouts. Keywords: Constellation, human factors, tools, processes, habitat, outpost, Net Habitable Volume, Cooper-Harper.

  20. Evaluation of disease modifying activity of Coriandrum sativum in experimental models

    PubMed Central

    Nair, Vinod; Singh, Surender; Gupta, Y.K.

    2012-01-01

    Background & objectives: Coriandrum sativum (CS), has been widely used in traditional systems of medicine for treatment of rheumatoid arthritis. However, the mechanism of action for its antiarthritic effects is not clearly known. Therefore, the present study was carried out to evaluate the antiarthritic activity of CS in rats in two experimental models. Methods: The antiarthritic activity of CS seed hydroalcoholic extract (CSHE) was evaluated in adult Wistar rats by using two experimental models, viz. formaldehyde and Complete Freund's adjuvant (CFA) induced arthritis. The expression of pro-inflammatory cytokines (predominantly contributed by macrophages) was also evaluated. TNF-α level was estimated in serum by ELISA method. TNF-R1, IL-1 β and IL-6 expression in the synovium was analysed by immunohistochemistry. Results: CSHE produced a dose dependent inhibition of joint swelling as compared to control animals in both, formaldehyde and CFA induced arthritis. Although there was a dose dependent increase in serum TNF-α levels in the CSHE treated groups as compared to control, the synovial expression of macrophage derived pro-inflammatory cytokines/cytokine receptor was found to be lower in the CSHE treated groups as compared to control. Interpretation & conclusions: Our results demonstrate that the antiarthritic activity of CSHE may be attributed to the modulation of pro-inflammatory cytokines in the synovium. In further studies CSHE could be explored to be developed as a disease modifying agent in the treatment of RA. PMID:22446868

  1. The usefulness of design of experimentation in defining the effect difficult airway factors and training have on simulator oral-tracheal intubation success rates in novice intubators.

    PubMed

    Thomas, Frank; Carpenter, Judi; Rhoades, Carol; Holleran, Renee; Snow, Gregory

    2010-04-01

    This exploratory study examined novice intubators and the effect difficult airway factors have on pre- and posttraining oral-tracheal simulation intubation success rates. Using a two-level, full-factorial design of experimentation (DOE) involving a combination of six airway factors (curved vs. straight laryngoscope blade, trismus, tongue edema, laryngeal spasm, pharyngeal obstruction, or cervical immobilization), 64 airway scenarios were prospectively randomized to 12 critical care nurses to evaluate pre- and posttraining first-pass intubation success rates on a simulator. Scenario variables and intubation outcomes were analyzed using a generalized linear mixed-effects model to determine two-way main and interactive effects. Interactive effects between the six study factors were nonsignificant (p = 0.69). For both pre- and posttraining, main effects showed the straight blade (p = 0.006), tongue edema (p = 0.0001), and laryngeal spasm (p = 0.004) significantly reduced success rates, while trismus (p = 0.358), pharyngeal obstruction (p = 0.078), and cervical immobilization did not significantly change the success rate. First-pass intubation success rate on the simulator significantly improved (p = 0.005) from pre- (19%) to posttraining (36%). Design of experimentation is useful in analyzing the effect difficult airway factors and training have on simulator intubation success rates. Future quality improvement DOE simulator research studies should be performed to help clarify the relationship between simulator factors and patient intubation rates.

  2. Effects of inhalational anaesthetics in experimental allergic asthma.

    PubMed

    Burburan, S M; Silva, J D; Abreu, S C; Samary, C S; Guimarães, I H L; Xisto, D G; Morales, M M; Rocco, P R M

    2014-06-01

    We evaluated whether isoflurane, halothane and sevoflurane attenuate the inflammatory response and improve lung morphofunction in experimental asthma. Fifty-six BALB/c mice were sensitised and challenged with ovalbumin and anaesthetised with isoflurane, halothane, sevoflurane or pentobarbital sodium for one hour. Lung mechanics and histology were evaluated. Gene expression of pro-inflammatory (tumour necrosis factor-α), pro-fibrogenic (transforming growth factor-β) and pro-angiogenic (vascular endothelial growth factor) mediators, as well as oxidative process modulators, were analysed. These modulators included nuclear factor erythroid-2 related factor 2, sirtuin, catalase and glutathione peroxidase. Isoflurane, halothane and sevoflurane reduced airway resistance, static lung elastance and atelectasis when compared with pentobarbital sodium. Sevoflurane minimised bronchoconstriction and cell infiltration, and decreased tumour necrosis factor-α, transforming growth factor-β, vascular endothelial growth factor, sirtuin, catalase and glutathione peroxidase, while increasing nuclear factor erythroid-2-related factor 2 expression. Sevoflurane down-regulated inflammatory, fibrogenic and angiogenic mediators, and modulated oxidant-antioxidant imbalance, improving lung function in this model of asthma. © 2014 The Association of Anaesthetists of Great Britain and Ireland.

  3. Automated measurement of birefringence - Development and experimental evaluation of the techniques

    NASA Technical Reports Server (NTRS)

    Voloshin, A. S.; Redner, A. S.

    1989-01-01

    Traditional photoelasticity has started to lose its appeal since it requires a well-trained specialist to acquire and interpret results. A spectral-contents-analysis approach may help to revive this old, but still useful technique. Light intensity of the beam passed through the stressed specimen contains all the information necessary to automatically extract the value of retardation. This is done by using a photodiode array to investigate the spectral contents of the light beam. Three different techniques to extract the value of retardation from the spectral contents of the light are discussed and evaluated. An experimental system was built which demonstrates the ability to evaluate retardation values in real time.

  4. Experimental manipulation of psychosocial exposure and questionnaire sensitivity in a simulated manufacturing setting.

    PubMed

    Ikuma, Laura H; Babski-Reeves, Kari; Nussbaum, Maury A

    2009-05-01

    The objectives of this study were to determine the efficacy of experimental manipulations of psychosocial exposures and to evaluate the sensitivity of a psychosocial questionnaire by determining the factors perceived. A 50-item questionnaire was developed from the job content questionnaire (JCQ) and the quality of worklife survey (QWL). The experiment involved simulated work at different physical and psychosocial levels. Forty-eight participants were exposed to two levels of one psychosocial manipulation (job control, job demands, social support, or time pressure). Significantly different questionnaire responses supported the effectiveness of psychosocial manipulations. Exploratory factor analysis revealed five factors: skill discretion and decision authority, stress level and supervisor support, physical demands, quality of coworker support, and decision-making support. These results suggest that psychosocial factors can be manipulated experimentally, and that questionnaires can distinguish perceptions of these factors. These questionnaires may be used to assess perceptions of psychosocial factors in experimental settings.

  5. 10 CFR 100.20 - Factors to be considered when evaluating sites.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Factors to be considered when evaluating sites. 100.20 Section 100.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) REACTOR SITE CRITERIA Evaluation Factors... analysis or that may have an impact upon plant design (such as maximum probable wind speed and...

  6. 10 CFR 100.20 - Factors to be considered when evaluating sites.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Factors to be considered when evaluating sites. 100.20 Section 100.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) REACTOR SITE CRITERIA Evaluation Factors... analysis or that may have an impact upon plant design (such as maximum probable wind speed and...

  7. 10 CFR 100.20 - Factors to be considered when evaluating sites.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Factors to be considered when evaluating sites. 100.20 Section 100.20 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) REACTOR SITE CRITERIA Evaluation Factors... analysis or that may have an impact upon plant design (such as maximum probable wind speed and...

  8. Trefoil Factor 3 as an Endocrine Neuroprotective Factor from the Liver in Experimental Cerebral Ischemia/Reperfusion Injury

    PubMed Central

    Liu, Shu Q.; Roberts, Derek; Zhang, Brian; Ren, Yupeng; Zhang, Li-Qun; Wu, Yu H.

    2013-01-01

    Cerebral ischemia, while causing neuronal injury, can activate innate neuroprotective mechanisms, minimizing neuronal death. In this report, we demonstrate that experimental cerebral ischemia/reperfusion injury in the mouse causes upregulation of the secretory protein trefoil factor 3 (TFF3) in the hepatocyte in association with an increase in serum TFF3. Partial hepatectomy (~60% liver resection) immediately following cerebral injury significantly lowered the serum level of TFF3, suggesting a contribution of the liver to the elevation of serum TFF3. Compared to wild-type mice, TFF3-/- mice exhibited a significantly higher activity of caspase 3 and level of cell death in the ischemic cerebral lesion, a larger fraction of cerebral infarcts, and a smaller fraction of the injured cerebral hemisphere, accompanied by severer forelimb motor deficits. Intravenous administration of recombinant TFF3 reversed changes in cerebral injury and forelimb motor function due to TFF3 deficiency. These observations suggest an endocrine neuroprotective mechanism involving TFF3 from the liver in experimental cerebral ischemia/reperfusion injury. PMID:24204940

  9. Analysis of Academic Administrators' Attitudes: Annual Evaluations and Factors That Improve Teaching

    ERIC Educational Resources Information Center

    Cherry, Brian D.; Grasse, Nathan; Kapla, Dale; Hamel, Brad

    2017-01-01

    This article examines academic administrators' attitudes towards the academic evaluation process in the US and those factors that are utilised to improve teaching. We use path regressions to examine satisfaction with evaluation procedures, as well as the direct and indirect effects of these factors on perceptions of whether the evaluation process…

  10. Experimental evaluation of three leak detection and location concepts for space stations

    NASA Technical Reports Server (NTRS)

    Scherb, M. V.; Kazokas, G. P.; Zelik, J. A.; Mastandrea, J. R.; Mackallor, D. C.

    1972-01-01

    Three leak (or precursor damage modes) detection and location concepts for space station overboard leakage were evaluated experimentally. The techniques are: (1) static and dynamic seal leak detector sensing of moisture or all gases in space cabin atmosphere, (2) active ultrasonic Lamb-wave detection of flaws or cracks in cabin wall, and (3) impact gage detection of stress waves induced in cabin pressure wall by meteoroid or orbital impact. The experimental results obtained in the program demonstrated that all three leak detection and location concepts are feasible. With further development, the methods can be integrated into an effective damage control system for advanced manned earth-orbital systems.

  11. 47 CFR 1.3003 - Mandatory factors for evaluating conflicts of interest.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Mandatory factors for evaluating conflicts of... Unconditional Gifts, Donations and Bequests § 1.3003 Mandatory factors for evaluating conflicts of interest. No... create a conflict of interest or the appearance of a conflict of interest. In making conflict of interest...

  12. SFCHECK: a unified set of procedures for evaluating the quality of macromolecular structure-factor data and their agreement with the atomic model.

    PubMed

    Vaguine, A A; Richelle, J; Wodak, S J

    1999-01-01

    In this paper we present SFCHECK, a stand-alone software package that features a unified set of procedures for evaluating the structure-factor data obtained from X-ray diffraction experiments and for assessing the agreement of the atomic coordinates with these data. The evaluation is performed completely automatically, and produces a concise PostScript pictorial output similar to that of PROCHECK [Laskowski, MacArthur, Moss & Thornton (1993). J. Appl. Cryst. 26, 283-291], greatly facilitating visual inspection of the results. The required inputs are the structure-factor amplitudes and the atomic coordinates. Having those, the program summarizes relevant information on the deposited structure factors and evaluates their quality using criteria such as data completeness, structure-factor uncertainty and the optical resolution computed from the Patterson origin peak. The dependence of various parameters on the nominal resolution (d spacing) is also given. To evaluate the global agreement of the atomic model with the experimental data, the program recomputes the R factor, the correlation coefficient between observed and calculated structure-factor amplitudes and Rfree (when appropriate). In addition, it gives several estimates of the average error in the atomic coordinates. The local agreement between the model and the electron-density map is evaluated on a per-residue basis, considering separately the macromolecule backbone and side-chain atoms, as well as solvent atoms and heterogroups. Among the criteria are the normalized average atomic displacement, the local density correlation coefficient and the polymer chain connectivity. The possibility of computing these criteria using the omit-map procedure is also provided. The described software should be a valuable tool in monitoring the refinement procedure and in assessing structures deposited in databases.

  13. An Experimental Evaluation of Oil Pumping Rings

    NASA Technical Reports Server (NTRS)

    Eusepi, M. W.; Walowit, J.; Cohen, M.

    1981-01-01

    The design and construction of a reciprocating test vehicle to be used in evaluating hydrodynamic oil pumping rings are discussed. In addition, experimental test data are presented for three pumping ring designs that were constructed from Tin-Based Babbitt (SAE 11), Bearing Bronze (SAE 660), and Mechanical Carbon Graphite (Union Carbide Grade CNF-J). Data of pumped flow rate versus delivered pressure, as well as friction loss, are reported for the following conditions: frequencies of 10, 35 and 45 Hz; strokes of 25.4 mm (1.00 in.), 38.1 mm (1.50 in.) and 50.8 mm (2.00 in.) oil inlet temperature of 49 degrees (120 degrees); and pumping ring close-in pressures of 10.3 MPa (1500 lb/square inch. A 20W40 automotive oil was used for all tests. The maximum delivered pressure was 11 MPa (1600 lb/square inch. An analysis of hydrodynamic oil pumping rings was performed and the results of the analysis were compared to measured test data.

  14. Factors Most Likely to Contribute to Positive Course Evaluations

    ERIC Educational Resources Information Center

    VanMaaren, Victoria G.; Jaquett, Caroline M.; Williams, Robert L.

    2016-01-01

    The purpose of this study was to determine the extent to which students differentially rated ten factors likely to affect their ratings on overall course evaluations. Students (N = 148) in several sections of an undergraduate educational psychology course indicated their preferences among several designated factors. We found remarkable similarity…

  15. Nodal weighting factor method for ex-core fast neutron fluence evaluation

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

    Chiang, R. T.

    The nodal weighting factor method is developed for evaluating ex-core fast neutron flux in a nuclear reactor by utilizing adjoint neutron flux, a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV, the unit fission source, and relative assembly nodal powers. The method determines each nodal weighting factor for ex-core neutron fast flux evaluation by solving the steady-state adjoint neutron transport equation with a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV as the adjoint source, by integrating the unit fission source with a typical fission spectrum to the solved adjointmore » flux over all energies, all angles and given nodal volume, and by dividing it with the sum of all nodal weighting factors, which is a normalization factor. Then, the fast neutron flux can be obtained by summing the various relative nodal powers times the corresponding nodal weighting factors of the adjacent significantly contributed peripheral assembly nodes and times a proper fast neutron attenuation coefficient over an operating period. A generic set of nodal weighting factors can be used to evaluate neutron fluence at the same location for similar core design and fuel cycles, but the set of nodal weighting factors needs to be re-calibrated for a transition-fuel-cycle. This newly developed nodal weighting factor method should be a useful and simplified tool for evaluating fast neutron fluence at selected locations of interest in ex-core components of contemporary nuclear power reactors. (authors)« less

  16. Evaluating voice characteristics of first-year acting students in Israel: factor analysis.

    PubMed

    Amir, Ofer; Primov-Fever, Adi; Kushnir, Tami; Kandelshine-Waldman, Osnat; Wolf, Michael

    2013-01-01

    Acting students require diverse, high-quality, and high-intensity vocal performance from early stages of their training. Demanding vocal activities, before developing the appropriate vocal skills, put them in high risk for developing vocal problems. A retrospective analysis of voice characteristics of first-year acting students using several voice evaluation tools. A total of 79 first-year acting students (55 women and 24 men) were assigned into two study groups: laryngeal findings (LFs) and no laryngeal findings, based on stroboscopic findings. Their voice characteristics were evaluated using acoustic analysis, aerodynamic examination, perceptual scales, and self-report questionnaires. Results obtained from each set of measures were examined using a factor analysis approach. Significant differences between the two groups were found for a single fundamental frequency (F(0))-Regularity factor; a single Grade, Roughness, Breathiness, Asthenia, Strain perceptual factor; and the three self-evaluation factors. Gender differences were found for two acoustic analysis factors, which were based on F(0) and its derivatives, namely an aerodynamic factor that represents expiratory volume measurements and a single self-evaluation factor that represents the tendency to seek therapy. Approximately 50% of the first-year acting students had LFs. These students differed from their peers in the control group in a single acoustic analysis factor, as well as perceptual and self-report factors. No group differences, however, were found for the aerodynamic factors. Early laryngeal examination and voice evaluation of future professional voice users could provide a valuable individual baseline, to which later examinations could be compared, and assist in providing personally tailored treatment. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  17. Experimental Evaluation of the Free Piston Engine - Linear Alternator (FPLA)

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

    Leick, Michael T.; Moses, Ronald W.

    2015-03-01

    This report describes the experimental evaluation of a prototype free piston engine - linear alternator (FPLA) system developed at Sandia National Laboratories. The opposed piston design wa developed to investigate its potential for use in hybrid electric vehicles (HEVs). The system is mechanically simple with two - stroke uniflow scavenging for gas exchange and timed port fuel injection for fuel delivery, i.e. no complex valving. Electrical power is extracted from piston motion through linear alternators wh ich also provide a means for passive piston synchronization through electromagnetic coupling. In an HEV application, this electrical power would be used to chargemore » the batteries. The engine - alternator system was designed, assembled and operated over a 2 - year period at Sandia National Laboratories in Livermore, CA. This report primarily contains a description of the as - built system, modifications to the system to enable better performance, and experimental results from start - up, motoring, and hydrogen combus tion tests.« less

  18. Antioxidative Categorization of Twenty Amino Acids Based on Experimental Evaluation.

    PubMed

    Xu, Naijin; Chen, Guanqun; Liu, Hui

    2017-11-27

    In view of the great importance bestowed on amino acids as antioxidants in oxidation resistance, we attempted two common redox titration methods in this report, including micro-potassium permanganate titration and iodometric titration, to measure the antioxidative capacity of 20 amino acids, which are the construction units of proteins in living organisms. Based on the relative intensities of the antioxidative capacity, we further conducted a quantitative comparison and found out that the product of experimental values obtained from the two methods was proven to be a better indicator for evaluating the relative antioxidative capacity of amino acids. The experimental results were largely in accordance with structural analysis made on amino acids. On the whole, the 20 amino acids concerned could be divided into two categories according to their antioxidative capacity. Seven amino acids, including tryptophan, methionine, histidine, lysine, cysteine, arginine and tyrosine, were greater in total antioxidative capacity compared with the other 13 amino acids.

  19. Numerical and experimental evaluation of microfluidic sorting devices.

    PubMed

    Taylor, Jay K; Ren, Carolyn L; Stubley, G D

    2008-01-01

    The development of lab-on-a-chip devices calls for the isolation or separation of specific bioparticles or cells. The design of a miniaturized cell-sorting device for handheld operation must follow the strict parameters associated with lab-on-a-chip technology. The limitations include applied voltage, high efficiency of cell-separation, reliability, size, flow control, and cost, among others. Currently used designs have achieved successful levels of cell isolation; however, further improvements in the microfluidic chip design are important to incorporate into larger systems. This study evaluates specific design modifications that contribute to the reduction of required applied potential aiming for developing portable devices, improved operation reliability by minimizing induced pressure disturbance when electrokinetic pumping is employed, and improved flow control by incorporating directing streams achieving dynamic sorting and counting. The chip designs fabricated in glass and polymeric materials include asymmetric channel widths for sample focusing, nonuniform channel depth for minimizing induced pressure disturbance, directing streams to assist particle flow control, and online filters for reducing channel blockage. Fluorescence-based visualization experimental results of electrokinetic focusing, flow field phenomena, and dynamic sorting demonstrate the advantages of the chip design. Numerical simulations in COMSOL are validated by the experimental data and used to investigate the effects of channel geometry and fluid properties on the flow field.

  20. An evaluation of fluorescent elastomer for marking bluegills in experimental studies

    USGS Publications Warehouse

    Dewey, Michael R.; Zigler, Steven J.

    1996-01-01

    We evaluated subdermal injection of a fluorescent elastomer for marking bluegills Lepomis macrochirus in laboratory and pond studies. Marking did not affect the growth or survival of adult or juvenile bluegills. Marks were visible for at least 6 months. This technique is a reliable, relatively inexpensive marking method for the identification of individual fish in experimental studies. Costs of application range from US$0.01 to $0.03 per mark.

  1. Evaluation of the Big-Two-Factor Theory of Motivation Orientations: An Evaluation of Jingle-Jangle Fallacies.

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Craven, Rhonda G.; McInerney, Dennis; Debus, Raymond L.

    Motivation orientation research consistently finds two factors, Performance and Learning, that overlap substantially with other factors coming from different theoretical perspectives of motivation. Similar to related work in the Big-Five Theory of Personality, researchers posited a Big-Two-Factor Theory of motivation orientation and evaluated the…

  2. A new experimental design method to optimize formulations focusing on a lubricant for hydrophilic matrix tablets.

    PubMed

    Choi, Du Hyung; Shin, Sangmun; Khoa Viet Truong, Nguyen; Jeong, Seong Hoon

    2012-09-01

    A robust experimental design method was developed with the well-established response surface methodology and time series modeling to facilitate the formulation development process with magnesium stearate incorporated into hydrophilic matrix tablets. Two directional analyses and a time-oriented model were utilized to optimize the experimental responses. Evaluations of tablet gelation and drug release were conducted with two factors x₁ and x₂: one was a formulation factor (the amount of magnesium stearate) and the other was a processing factor (mixing time), respectively. Moreover, different batch sizes (100 and 500 tablet batches) were also evaluated to investigate an effect of batch size. The selected input control factors were arranged in a mixture simplex lattice design with 13 experimental runs. The obtained optimal settings of magnesium stearate for gelation were 0.46 g, 2.76 min (mixing time) for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The optimal settings for drug release were 0.33 g, 7.99 min for a 100 tablet batch and 1.54 g, 6.51 min for a 500 tablet batch. The exact ratio and mixing time of magnesium stearate could be formulated according to the resulting hydrophilic matrix tablet properties. The newly designed experimental method provided very useful information for characterizing significant factors and hence to obtain optimum formulations allowing for a systematic and reliable experimental design method.

  3. An experimentally validated network of nine haematopoietic transcription factors reveals mechanisms of cell state stability

    PubMed Central

    Schütte, Judith; Wang, Huange; Antoniou, Stella; Jarratt, Andrew; Wilson, Nicola K; Riepsaame, Joey; Calero-Nieto, Fernando J; Moignard, Victoria; Basilico, Silvia; Kinston, Sarah J; Hannah, Rebecca L; Chan, Mun Chiang; Nürnberg, Sylvia T; Ouwehand, Willem H; Bonzanni, Nicola; de Bruijn, Marella FTR; Göttgens, Berthold

    2016-01-01

    Transcription factor (TF) networks determine cell-type identity by establishing and maintaining lineage-specific expression profiles, yet reconstruction of mammalian regulatory network models has been hampered by a lack of comprehensive functional validation of regulatory interactions. Here, we report comprehensive ChIP-Seq, transgenic and reporter gene experimental data that have allowed us to construct an experimentally validated regulatory network model for haematopoietic stem/progenitor cells (HSPCs). Model simulation coupled with subsequent experimental validation using single cell expression profiling revealed potential mechanisms for cell state stabilisation, and also how a leukaemogenic TF fusion protein perturbs key HSPC regulators. The approach presented here should help to improve our understanding of both normal physiological and disease processes. DOI: http://dx.doi.org/10.7554/eLife.11469.001 PMID:26901438

  4. INCOMMANDS TDP: Human Factors Evaluation of the Command Decision Support Capability Prototype

    DTIC Science & Technology

    2009-03-01

    CDSC) design with guidelines and principles stipulated in the INCOMMANDS TDP Human Factors Design and Evaluation Guide. 2. Usability and Utility...INCOMMANDS CDSC. The Heuristic Evaluation helps to ensure that the design of system is compliant with HCI best practices. Whereas the Usability and...implemented to confirm compliance with the INCOMMANDS TDP Human Factors Design and Evaluation Guide

  5. Exploring Non-Instructional Factors in Student Evaluations

    ERIC Educational Resources Information Center

    Ali, Holi Ibrahim Holi; Al Ajmi, Ahmed Ali Saleh

    2013-01-01

    The use of student ratings to measure instructors' teaching performance and effectiveness in tertiary education has been an important but controversial tool in the improvement of teaching quality during the past few decades. This is an attempt to explore non-instructional factors of student evaluations by discussing and reviewing relevant…

  6. Experimental sugar beet cultivars evaluated for rhizomania resistance and storability in Idaho, 2016

    USDA-ARS?s Scientific Manuscript database

    Rhizomania caused by Beet necrotic yellow vein virus (BNYVV) and storage losses are serious sugar beet production problems. To identify sugar beet cultivars with resistance to BNYVV and evaluate storability, 31 experimental cultivars were screened by growing them in a sugar beet field infested with...

  7. Interviewer as instrument: accounting for human factors in evaluation research.

    PubMed

    Brown, Joel H

    2006-04-01

    This methodological study examines an original data collection model designed to incorporate human factors and enhance data richness in qualitative and evaluation research. Evidence supporting this model is drawn from in-depth youth and adult interviews in one of the largest policy/program evaluations undertaken in the United States, the Drug, Alcohol, and Tobacco Education evaluation (77 districts, 118 schools). When applying the explicit observation technique (EOT)--the strategic and nonjudgmental disclosure of nonverbal human factor cues by the interviewer to the respondent during interview--data revealed the observation disclosure pattern. Here, respondents linked perceptions with policy or program implementation or effectiveness evidence. Although more research is needed, it is concluded that the EOT yields richer data when compared with traditional semistructured interviews and, thus, holds promise to enhance qualitative and evaluation research methods. Validity and reliability as well as qualitative and evaluation research considerations are discussed.

  8. Anaerobic treatment of complex chemical wastewater in a sequencing batch biofilm reactor: process optimization and evaluation of factor interactions using the Taguchi dynamic DOE methodology.

    PubMed

    Venkata Mohan, S; Chandrasekhara Rao, N; Krishna Prasad, K; Murali Krishna, P; Sreenivas Rao, R; Sarma, P N

    2005-06-20

    The Taguchi robust experimental design (DOE) methodology has been applied on a dynamic anaerobic process treating complex wastewater by an anaerobic sequencing batch biofilm reactor (AnSBBR). For optimizing the process as well as to evaluate the influence of different factors on the process, the uncontrollable (noise) factors have been considered. The Taguchi methodology adopting dynamic approach is the first of its kind for studying anaerobic process evaluation and process optimization. The designed experimental methodology consisted of four phases--planning, conducting, analysis, and validation connected sequence-wise to achieve the overall optimization. In the experimental design, five controllable factors, i.e., organic loading rate (OLR), inlet pH, biodegradability (BOD/COD ratio), temperature, and sulfate concentration, along with the two uncontrollable (noise) factors, volatile fatty acids (VFA) and alkalinity at two levels were considered for optimization of the anae robic system. Thirty-two anaerobic experiments were conducted with a different combination of factors and the results obtained in terms of substrate degradation rates were processed in Qualitek-4 software to study the main effect of individual factors, interaction between the individual factors, and signal-to-noise (S/N) ratio analysis. Attempts were also made to achieve optimum conditions. Studies on the influence of individual factors on process performance revealed the intensive effect of OLR. In multiple factor interaction studies, biodegradability with other factors, such as temperature, pH, and sulfate have shown maximum influence over the process performance. The optimum conditions for the efficient performance of the anaerobic system in treating complex wastewater by considering dynamic (noise) factors obtained are higher organic loading rate of 3.5 Kg COD/m3 day, neutral pH with high biodegradability (BOD/COD ratio of 0.5), along with mesophilic temperature range (40 degrees C), and

  9. Experimental design to evaluate directed adaptive mutation in Mammalian cells.

    PubMed

    Bordonaro, Michael; Chiaro, Christopher R; May, Tobias

    2014-12-09

    We describe the experimental design for a methodological approach to determine whether directed adaptive mutation occurs in mammalian cells. Identification of directed adaptive mutation would have profound practical significance for a wide variety of biomedical problems, including disease development and resistance to treatment. In adaptive mutation, the genetic or epigenetic change is not random; instead, the presence and type of selection influences the frequency and character of the mutation event. Adaptive mutation can contribute to the evolution of microbial pathogenesis, cancer, and drug resistance, and may become a focus of novel therapeutic interventions. Our experimental approach was designed to distinguish between 3 types of mutation: (1) random mutations that are independent of selective pressure, (2) undirected adaptive mutations that arise when selective pressure induces a general increase in the mutation rate, and (3) directed adaptive mutations that arise when selective pressure induces targeted mutations that specifically influence the adaptive response. The purpose of this report is to introduce an experimental design and describe limited pilot experiment data (not to describe a complete set of experiments); hence, it is an early report. An experimental design based on immortalization of mouse embryonic fibroblast cells is presented that links clonal cell growth to reversal of an inactivating polyadenylation site mutation. Thus, cells exhibit growth only in the presence of both the countermutation and an inducing agent (doxycycline). The type and frequency of mutation in the presence or absence of doxycycline will be evaluated. Additional experimental approaches would determine whether the cells exhibit a generalized increase in mutation rate and/or whether the cells show altered expression of error-prone DNA polymerases or of mismatch repair proteins. We performed the initial stages of characterizing our system and have limited preliminary data

  10. Evaluation of Site Effects Using Numerical and Experimental Analyses In Cittas Di Castello (italy)

    NASA Astrophysics Data System (ADS)

    Pergalani, F.; de Franco, R.; Compagnoni, M.; Caielli, G.

    In the paper the results of the numerical and experimental analyses, in a site of the Umbria Region (Città di Castello - PG), finalized to the evaluations of site effects are shown. The aim of the work was to compare the two type of analyses, to give some methodologies that may be used at the level of urban planning, to consider these as- pects. Therefore a series of geologic, geomorphologic (1:5.000 scale), geotechnic and seismic analyses have been carried out, to identify the areas affected to local effects and to characterize the lithotechnic units. The expected seismic inputs are been indi- viduated and 2D (Quad4M, Hudson et al., 1993) numerical analyses have been done. An experimental analysis, using the registrations of small events, has been done. The results, for the two approaches, were performed in terms of elastic pseudo-acceleration spectra and amplification factors, as a ratio between spectral intensity (Housner, 1952), calculated using the pseudo-velocity spectra, in the periods of 0.1-0.5 s and 0.1-2.5 s of output and input. The results have been analyzed and compared, to give a method- ology that may be exhaustive and precise. The conclusions can be summarized in the following points: u° the results of the two approaches are coherent; u° the differences between the two approaches are: the use of the numerical analysis is easy and quick but, in this case, the use of 2D analysis produces a simplification of real geometry; the use of experimental analysis allows to consider the 3D conditions, but, in this case, the registrations of events characterized by low energy, do not allow to consider the non linear behavior of materials, moreover it is necessary to perform the registrations for a period depending from the seismicity of the region (1 month - two years); u° the possi- bility of integration of the two methodologies allows to perform a complete analysis, using the advantages of the two methods. Housner G.W., Spectrum Intensities of strong

  11. 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.

  12. Evaluating Amazon's Mechanical Turk as a Tool for Experimental Behavioral Research

    PubMed Central

    Crump, Matthew J. C.; McDonnell, John V.; Gureckis, Todd M.

    2013-01-01

    Amazon Mechanical Turk (AMT) is an online crowdsourcing service where anonymous online workers complete web-based tasks for small sums of money. The service has attracted attention from experimental psychologists interested in gathering human subject data more efficiently. However, relative to traditional laboratory studies, many aspects of the testing environment are not under the experimenter's control. In this paper, we attempt to empirically evaluate the fidelity of the AMT system for use in cognitive behavioral experiments. These types of experiment differ from simple surveys in that they require multiple trials, sustained attention from participants, comprehension of complex instructions, and millisecond accuracy for response recording and stimulus presentation. We replicate a diverse body of tasks from experimental psychology including the Stroop, Switching, Flanker, Simon, Posner Cuing, attentional blink, subliminal priming, and category learning tasks using participants recruited using AMT. While most of replications were qualitatively successful and validated the approach of collecting data anonymously online using a web-browser, others revealed disparity between laboratory results and online results. A number of important lessons were encountered in the process of conducting these replications that should be of value to other researchers. PMID:23516406

  13. Experimental Infections with Mycoplasma agalactiae Identify Key Factors Involved in Host-Colonization

    PubMed Central

    Baranowski, Eric; Bergonier, Dominique; Sagné, Eveline; Hygonenq, Marie-Claude; Ronsin, Patricia; Berthelot, Xavier; Citti, Christine

    2014-01-01

    Mechanisms underlying pathogenic processes in mycoplasma infections are poorly understood, mainly because of limited sequence similarities with classical, bacterial virulence factors. Recently, large-scale transposon mutagenesis in the ruminant pathogen Mycoplasma agalactiae identified the NIF locus, including nifS and nifU, as essential for mycoplasma growth in cell culture, while dispensable in axenic media. To evaluate the importance of this locus in vivo, the infectivity of two knock-out mutants was tested upon experimental infection in the natural host. In this model, the parental PG2 strain was able to establish a systemic infection in lactating ewes, colonizing various body sites such as lymph nodes and the mammary gland, even when inoculated at low doses. In these PG2-infected ewes, we observed over the course of infection (i) the development of a specific antibody response and (ii) dynamic changes in expression of M. agalactiae surface variable proteins (Vpma), with multiple Vpma profiles co-existing in the same animal. In contrast and despite a sensitive model, none of the knock-out mutants were able to survive and colonize the host. The extreme avirulent phenotype of the two mutants was further supported by the absence of an IgG response in inoculated animals. The exact role of the NIF locus remains to be elucidated but these data demonstrate that it plays a key role in the infectious process of M. agalactiae and most likely of other pathogenic mycoplasma species as many carry closely related homologs. PMID:24699671

  14. Redundancy of stereoscopic images: Experimental evaluation

    NASA Astrophysics Data System (ADS)

    Yaroslavsky, L. P.; Campos, J.; Espínola, M.; Ideses, I.

    2005-12-01

    With the recent advancement in visualization devices over the last years, we are seeing a growing market for stereoscopic content. In order to convey 3D content by means of stereoscopic displays, one needs to transmit and display at least 2 points of view of the video content. This has profound implications on the resources required to transmit the content, as well as demands on the complexity of the visualization system. It is known that stereoscopic images are redundant which may prove useful for compression and may have positive effect on the construction of the visualization device. In this paper we describe an experimental evaluation of data redundancy in color stereoscopic images. In the experiments with computer generated and real life test stereo images, several observers visually tested the stereopsis threshold and accuracy of parallax measurement in anaglyphs and stereograms as functions of the blur degree of one of two stereo images. In addition, we tested the color saturation threshold in one of two stereo images for which full color 3D perception with no visible color degradations was maintained. The experiments support a theoretical estimate that one has to add, to data required to reproduce one of two stereoscopic images, only several percents of that amount of data in order to achieve stereoscopic perception.

  15. [Experimental study on the transforming growth factor β3 combined with dental pulp stem cells in early bone integration of implant].

    PubMed

    Guzalinuer, Ababaikeli; Muhetaer, Huojia; Wu, H; Paerhati, Abudureheman

    2018-04-09

    Objective: To establish the experimental model of rabbit mandibular anterior implant repair and evaluate the effects of transforming growth factor (TGF)-β3 and dental pulp stem cells (DPSC) in promoting the bone integration of implant. Methods: The New Zealand rabbits were randomly divided into experimental group, control group and blank group (6 rabbits for each group) . In the experimental group, the implant area was filled with the mixture of TGF-β3, DPSC and Bio-oss powder. In the control group, the implant area was filled with the mixture of DPSC and Bio-oss powder. In the blank group, the implant area was filled with the mixture of phosphate buffer solution and Bio-oss powder. Eighteen New Zealand rabbits were sacrificed in 2 weeks after procedure. The treated alveolar bone tissue was observed. The bone tissue around the implant were estimated by HE staining, immunocytochemical staining and real-time quantitative PCR. Results: The implants were no shedding nor loose. HE staining shows the blank group had a sparse trabecular bone and a small amount of blood vessel around the implant and no obvious new bone formation. The control group showed that the bone trabecula around the implant was sparse and slender, the osteoblasts were arranged linearly around the trabecular bone, a small amount of new bone formation was found around the implant. In the experimental group, there were more thick and dense trabecular bone around the implant, the surrounding osteoblasts were arranged in clusters. The osteoblasts were active and many new bone formed. Typical bone lacunae, bone cells and a large number of new blood vessels can be observed. Immunohistochemistry showed that the proportion of average positive area in the experimental group, control group, blank group were (24.6±5.3) %, (11.3±2.8) % and (7.6±3.8) % respectively. The expression of bone sialoprotein in experimental group were significantly higher than the other 2 groups( P= 0.000). Real-time quantitative

  16. Evaluating the role of curcum powder as a protective factor against bladder cancer--an experimental study.

    PubMed

    El-Mesallamy, Hala; Salman, Tarek M; Ashmawey, Abeer M; Osama, Nada

    2012-01-01

    Throughout human history, plant products have been used for many purposes including as medicines. Herbal products and spices can be used as preventive agents against cancer due to their antimicrobial, antioxidant and antitumorigenic properties. This study was designed to evaluate the potential protective effect of curcum in rats administered nitrosamine precursors; dibutylamine (DBA) and sodium nitrate (NaNO3); and infected with Escherichia coli (E. coli) and also to monitor changes in nuclear factor the Kappa B p65 (NF-κB p56) pathway and its downstream products, Bcl-2 and interleukin-6 (IL-6), in parallel with nitrosamine precursors, E. coli and curcum treatment. Rats were divided into three groups (n=25 each; except of control group, n+20). Group I a normal control group, group II administered DBA/NaNO3 in drinking water and infected with E. coli and group III was administered DBA/NaNO3 in drinking water, infected with E. coli and receiving standard diet containing 1% curcum powder. Histopathological examination reflected that the curcum treated group featured a lower incidence of urinary bladder lesions,and lower levels of NF-κB, Bcl-2 and IL-6, than the group receiving nitrosamine precursor and infected with E. coli. These findings suggested that curcum may have a protective role during the process of bladder carcinogenesis by inhibiting the NF-κB pathway and its downstream products.

  17. Experimental evaluation of ontology-based HIV/AIDS frequently asked question retrieval system.

    PubMed

    Ayalew, Yirsaw; Moeng, Barbara; Mosweunyane, Gontlafetse

    2018-05-01

    This study presents the results of experimental evaluations of an ontology-based frequently asked question retrieval system in the domain of HIV and AIDS. The main purpose of the system is to provide answers to questions on HIV/AIDS using ontology. To evaluate the effectiveness of the frequently asked question retrieval system, we conducted two experiments. The first experiment focused on the evaluation of the quality of the ontology we developed using the OQuaRE evaluation framework which is based on software quality metrics and metrics designed for ontology quality evaluation. The second experiment focused on evaluating the effectiveness of the ontology in retrieving relevant answers. For this we used an open-source information retrieval platform, Terrier, with retrieval models BM25 and PL2. For the measurement of performance, we used the measures mean average precision, mean reciprocal rank, and precision at 5. The results suggest that frequently asked question retrieval with ontology is more effective than frequently asked question retrieval without ontology in the domain of HIV/AIDS.

  18. Experimental evaluation of a translating nozzle sidewall radial turbine

    NASA Technical Reports Server (NTRS)

    Roelke, Richard J.; Rogo, Casimir

    1987-01-01

    An experimental performance evaluation was made of two movable sidewall variable area radial turbines. The turbine designs were representative of the gas generator turbine of a variable flow capacity rotorcraft engine. The first turbine was an uncooled design while the second turbine had a cooled nozzle but an uncooled rotor. The cooled nozzle turbine was evaluated both with and without coolant flow. The test results showed that the movable nozzle wall is a viable and efficient means to effectively control the flow capacity of a radial turbine. Peak efficiencies of the second turbine with and without nozzle coolant were 86.5 and 88 percent respectively. These values are comparable to pivoting vane variable geometry turbines; however, the decrease in efficiency as the flow was varied from the design value was much less for the movable wall turbine. Several design improvements which should increase the turbine efficiency one or two more points are identified. These design improvements include reduced leakage losses and relocation of the vane coolant ejection holes to reduce mainstream disturbance.

  19. Visual display aid for orbital maneuvering - Experimental evaluation

    NASA Technical Reports Server (NTRS)

    Grunwald, Arthur J.; Ellis, Stephen R.

    1993-01-01

    An interactive proximity operations planning system, which allows on-site planning of fuel-efficient, multiburn maneuvers in a potential multispacecraft environment, has been experimentally evaluated. An experiment has been carried out in which nonastronaut operators with brief initial training were required to plan a trajectory to retrieve an object accidentally separated from a dual-keel Space Station, for a variety of different orbital situations. The experiments have shown that these operators were able to plan workable trajectories, satisfying a number of operational constraints. Fuel use and planning time were strongly correlated, both with the angle at which the object was separated and with the existence of spatial constraints. Planning behavior was found to be strongly operator-dependent. This finding calls for the need for standardizing planning strategies through operator training or the use of semiautomated planning schemes.

  20. Experimental Evaluation of a Water Shield for a Surface Power Reactor

    NASA Technical Reports Server (NTRS)

    Pearson, J. B.; Reid, R.; Sadasivan, P.; Stewart, E.

    2007-01-01

    A water based shielding system is being investigated for use on initial lunar surface power systems. The use of water may lower overall cost (as compared to development cost for other materials) and simplify operations in the setup and handling. The thermal hydraulic performance of the shield is of significant interest. The mechanism for transferring heat through the shield is natural convection. A representative lunar surface reactor design is evaluated at various power levels in the Water Shield Testbed (WST) at the NASA Marshall Space Flight Center. The evaluation compares the experimental data from the WST to CFD models. Performance of a water shield on the lunar surface is predicted by CFD models anchored to test data, and by matching relevant dimensionless parameters.

  1. Human Factors Guidelines for the Evaluation of the Locomotive Cab

    DOT National Transportation Integrated Search

    1995-09-01

    This document presents human factors guidelines for the evaluation of the locomotive cab. These guidelines are part of : an effort to evaluate working conditions and safety in the locomotive cab. The guidelines will serve as a decision : making tool ...

  2. Experimental models of tracheobronchial stenoses: a useful tool for evaluating airway stents.

    PubMed

    Marquette, C H; Mensier, E; Copin, M C; Desmidt, A; Freitag, L; Witt, C; Petyt, L; Ramon, P

    1995-09-01

    Stent implantation is a conservative alternative to open operation for treating benign tracheobronchial strictures. Most of the presently available stents were primarily designed for endovascular use. Their respiratory use entails a risk of iatrogenic complications. From a scientific and from an ethical point of view these risks justify preclinical evaluation of new respiratory stents in experimental models of central airway stenoses. Therefore, an attempt was made to develop such models in piglets and adult minipigs. Tracheal stenoses were obtained by creating first a segmental tracheomalacia through extramucosal resection of cartilaginous arches. The fibrous component of the stenoses was then obtained through bronchoscopic application of a caustic agent causing progressive deep mucosal and submucosal injury. Stenoses of the main bronchi were created by topical application of the caustic agent only. These models demonstrated the typical features of benign fibromalacic tracheobronchial stenoses with constant recurrence after mechanical dilation. Preliminary experiments showed that short-term problems of tolerance of stent prototypes are easily demonstrable in these models. These experimental models, which simulate quite realistically human diseases, offer the opportunity to perfect new tracheobronchial stents specifically designed for respiratory use and to evaluate their long-term tolerance before their use in humans.

  3. Experimental evaluation of tailored chordwise deformable box beam and correlation with theory

    NASA Technical Reports Server (NTRS)

    Rehfield, Lawrence W.; Zischka, Peter J.; Chang, Stephen; Fentress, Michael L.; Ambur, Damodar R.

    1993-01-01

    This paper describes an experimental methodology based upon the use of a flexible sling support and load application system that has been created and utilized to evaluate a box beam which incorporates an elastic tailoring technology. The design technique used here for elastically tailoring the composite box beam structure is to produce exaggerated chordwise camber deformation of substantial magnitude to be of practical use in the new composite aircraft wings. The traditional methods such as a four-point bend test to apply constant bending moment with rigid fixtures inhibits the designed chordwise deformation from occurring and, hence, the need for the new test method. The experimental results for global camber and spanwise bending compliances correlate well with theoretical predictions based on a beam-like model.

  4. Enhancing Coping and Supporting Protective Factors after a Disaster: Findings From a Quasi-Experimental Study

    ERIC Educational Resources Information Center

    Powell, Tara; Thompson, Sanna J.

    2016-01-01

    Objective: This article presents the Journey of Hope (JoH), a school-based intervention for children who have experienced a collective trauma such as a natural disaster. Through the use of group work, the JoH focuses on building coping skills and enhancing protective factors to help children recover. Method: This quasi-experimental research…

  5. Experimental evaluation of radiosity for room sound-field prediction.

    PubMed

    Hodgson, Murray; Nosal, Eva-Marie

    2006-08-01

    An acoustical radiosity model was evaluated for how it performs in predicting real room sound fields. This was done by comparing radiosity predictions with experimental results for three existing rooms--a squash court, a classroom, and an office. Radiosity predictions were also compared with those by ray tracing--a "reference" prediction model--for both specular and diffuse surface reflection. Comparisons were made for detailed and discretized echograms, sound-decay curves, sound-propagation curves, and the variations with frequency of four room-acoustical parameters--EDT, RT, D50, and C80. In general, radiosity and diffuse ray tracing gave very similar predictions. Predictions by specular ray tracing were often very different. Radiosity agreed well with experiment in some cases, less well in others. Definitive conclusions regarding the accuracy with which the rooms were modeled, or the accuracy of the radiosity approach, were difficult to draw. The results suggest that radiosity predicts room sound fields with some accuracy, at least as well as diffuse ray tracing and, in general, better than specular ray tracing. The predictions of detailed echograms are less accurate, those of derived room-acoustical parameters more accurate. The results underline the need to develop experimental methods for accurately characterizing the absorptive and reflective characteristics of room surfaces, possible including phase.

  6. Design and experimental evaluation of robust controllers for a two-wheeled robot

    NASA Astrophysics Data System (ADS)

    Kralev, J.; Slavov, Ts.; Petkov, P.

    2016-11-01

    The paper presents the design and experimental evaluation of two alternative μ-controllers for robust vertical stabilisation of a two-wheeled self-balancing robot. The controllers design is based on models derived by identification from closed-loop experimental data. In the first design, a signal-based uncertainty representation obtained directly from the identification procedure is used, which leads to a controller of order 29. In the second design the signal uncertainty is approximated by an input multiplicative uncertainty, which leads to a controller of order 50, subsequently reduced to 30. The performance of the two μ-controllers is compared with the performance of a conventional linear quadratic controller with 17th-order Kalman filter. A proportional-integral controller of the rotational motion around the vertical axis is implemented as well. The control code is generated using Simulink® controller models and is embedded in a digital signal processor. Results from the simulation of the closed-loop system as well as experimental results obtained during the real-time implementation of the designed controllers are given. The theoretical investigation and experimental results confirm that the closed-loop system achieves robust performance in respect to the uncertainties related to the identified robot model.

  7. Stability-indicating LC assay for butenafine hydrochloride in creams using an experimental design for robustness evaluation and photodegradation kinetics study.

    PubMed

    Barth, Aline Bergesch; de Oliveira, Gabriela Bolfe; Malesuik, Marcelo Donadel; Paim, Clésio Soldatelli; Volpato, Nadia Maria

    2011-08-01

    A stability-indicating liquid chromatography method for the determination of the antifungal agent butenafine hydrochloride (BTF) in a cream was developed and validated using the Plackett-Burman experimental design for robustness evaluation. Also, the drug photodegradation kinetics was determined. The analytical column was operated with acetonitrile, methanol and a solution of triethylamine 0.3% adjusted to pH 4.0 (6:3:1) at a flow rate of 1 mL/min and detection at 283 nm. BTF extraction from the cream was done with n-butyl alcohol and methanol in ultrasonic bath. The performed degradation conditions were: acid and basic media with HCl 1M and NaOH 1M, respectively, oxidation with H(2)O(2) 10%, and the exposure to UV-C light. No interference in the BTF elution was verified. Linearity was assessed (r(2) = 0.9999) and ANOVA showed non-significative linearity deviation (p > 0.05). Adequate results were obtained for repeatability, intra-day precision, and accuracy. Critical factors were selected to examine the method robustness with the two-level Plackett-Burman experimental design and no significant factors were detected (p > 0.05). The BTF photodegradation kinetics was determined for the standard and for the cream, both in methanolic solution, under UV light at 254 nm. The degradation process can be described by first-order kinetics in both cases.

  8. Activin-A, transforming growth factor-beta, and myostatin signaling pathway in experimental dilated cardiomyopathy.

    PubMed

    Mahmoudabady, Maryam; Mathieu, Myrielle; Dewachter, Laurence; Hadad, Ielham; Ray, Lynn; Jespers, Pascale; Brimioulle, Serge; Naeije, Robert; McEntee, Kathleen

    2008-10-01

    The pathogenic mechanisms of dilated cardiomyopathy are still uncertain. A number of cytokines and growth factors participate in the remodeling process of the disease. We investigated the cardiac myostatin, transforming growth factor (TGF)beta, and activin-A/Smad growth inhibitory signaling pathway in experimental dilated cardiomyopathy. Transvenous endomyocardial biopsies of the interventricular septum were taken weekly in 15 beagle dogs during the development of heart failure (HF) induced by rapid pacing over a period of 7 weeks. Genes involved in the myostatin-TGFbeta-activin-A/Smad signaling pathway and the cardiac hypertrophic process were quantified by real-time quantitative polymerase chain reaction. Left ventricular volume, function, and mass were evaluated by echocardiography. Overpacing was associated with increased left ventricular volumes and decreased ejection fraction, whereas the left ventricular mass remained unchanged. TGFbeta was increased in moderate HF. Activin-A mRNA expression was 4-fold higher in overt congestive HF than at baseline. A 2-fold decrease of activin type II receptors and activin receptor interacting protein 2 gene expressions were observed, as well as a transient decrease of follistatin. Activin type I receptors, activin receptor interacting protein 1, follistatin-related gene, and myostatin remained unchanged. The inhibitory Smad 7, a negative feedback loop regulator of the Smad pathway, was overexpressed in severe HF. Gene expression of the cyclin-dependent kinase inhibitor p21, a direct target gene of the Smad pathway, was 8-fold up-regulated in HF, whereas cyclin D1 was down-regulated. We conclude that tachycardia-induced dilated cardiomyopathy is characterized by gene overexpression of the TGFbeta-activin-A/Smad signaling pathway and their target gene p21 and by the absence of ventricular hypertrophy.

  9. An experimental study of factors affecting the selective inhibition of sintering process

    NASA Astrophysics Data System (ADS)

    Asiabanpour, Bahram

    Selective Inhibition of Sintering (SIS) is a new rapid prototyping method that builds parts in a layer-by-layer fabrication basis. SIS works by joining powder particles through sintering in the part's body, and by sintering inhibition of some selected powder areas. The objective of this research has been to improve the new SIS process, which has been invented at USC. The process improvement is based on statistical design of experiments. To conduct the needed experiments a working machine and related path generator software were needed. The machine and its control software were made available prior to this research. The path generator algorithms and software had to be created. This program should obtain model geometry data from a CAD file and generate an appropriate path file for the printer nozzle. Also, the program should generate a simulation file for path file inspection using virtual prototyping. The activities related to path generator constitute the first part of this research, which has resulted in an efficient path generator. In addition, to reach an acceptable level of accuracy, strength, and surface quality in the fabricated parts, all effective factors in the SIS process should be identified and controlled. Simultaneous analytical and experimental studies were conducted to recognize effective factors and to control the SIS process. Also, it was known that polystyrene was the most appropriate polymer powder and saturated potassium iodide was the most effective inhibitor among the available candidate materials. In addition, statistical tools were applied to improve the desirable properties of the parts fabricated by the SIS process. An investigation of part strength was conducted using the Response Surface Methodology (RSM) and a region of acceptable operating conditions for the part strength was found. Then, through analysis of the experimental results, the impact of the factors on the final part surface quality and dimensional accuracy was modeled. After

  10. Factors affecting the abundance and distribution of European starlings at the San Joaquin Experimental Range

    Treesearch

    Kathryn L. Purcell; Jared Verner; Sylvia R. Mori

    2002-01-01

    We examined population trends and factors related to the abundance and presence of European starlings (Sturnus vulgaris) at the San Joaquin Experimental Range in the foothills of the western Sierra Nevada, 31 km east of Madera, California. Starlings first appeared there in low numbers in the late 1960s and are now abundant breeders. Simple models...

  11. Experimental evaluation criteria for constitutive models of time dependent cyclic plasticity

    NASA Technical Reports Server (NTRS)

    Martin, J. F.

    1986-01-01

    Notched members were tested at temperatures far above those recorded till now. Simulation of the notch root stress response was accomplished to establish notch stress-strain behavior. Cyclic stress-strain profiles across the net-section were recorded and on-line direct notch strain control was accomplished. Data are compared to three analysis techniques with good results. The objective of the study is to generate experimental data that can be used to evaluate the accuracy of constitutive models of time dependent cyclic plasticity.

  12. Epilepsy in cerebrovascular diseases: Review of experimental and clinical data with meta-analysis of risk factors.

    PubMed

    Ferlazzo, Edoardo; Gasparini, Sara; Beghi, Ettore; Sueri, Chiara; Russo, Emilio; Leo, Antonio; Labate, Angelo; Gambardella, Antonio; Belcastro, Vincenzo; Striano, Pasquale; Paciaroni, Maurizio; Pisani, Laura Rosa; Aguglia, Umberto

    2016-08-01

    Seizures may occur in close temporal association with a stroke or after a variable interval. Moreover, epilepsy is often encountered in patients with leukoaraiosis. Although early post-stroke seizures have been studied extensively, less attention has been paid to post-stroke epilepsy (PSE) and to epilepsy associated with leukoaraiosis (EAL). The aim of this paper is to review data concerning pathophysiology, prognosis, and treatment of PSE and EAL. We performed an extensive literature search to identify experimental and clinical articles on PSE and EAL. We also conducted a systematic review of risk factors for PSE and EAL among eligible studies. PSE is caused by enhanced neuronal excitability within and near the scar. The role played by white matter changes in EAL remains to be elucidated. Meta-analysis showed that cortical involvement (odds ratio [OR] 3.71, 95% confidence interval [CI] 2.34-5.90, p < 0.001), cerebral hemorrhage (OR 2.41, 95% CI 1.57-3.70, p < 0.001), and early seizures (OR 4.43, 95% CI 2.36-8.32, p < 0.001) are associated with an increased risk of PSE. As regards EAL, no prospective, population-based studies evaluated the role of different variables on seizure risk. Studies about the management of PSE are limited. PSE is generally well controlled by drugs. Data about risk factors, prognosis, and treatment of EAL are lacking. Pathophysiology and risk factors are well defined for PSE but need to be elucidated for EAL. Management of PSE and EAL relies on the clinician's judgment and should be tailored on an individual basis. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

  13. Experimental evaluation and thermodynamic system modeling of thermoelectric heat pump clothes dryer

    DOE PAGES

    Patel, Viral K.; Gluesenkamp, Kyle R.; Goodman, Dakota; ...

    2018-02-28

    Electric clothes dryers consume about 6% of US residential electricity consumption. Using a solid-state technology without refrigerant, thermoelectric (TE) heat pump dryers have the potential to be more efficient than units based on electric resistance and less expensive than units based on vapor compression. This study presents a steady state TE dryer model, and validates the model against results from an experimental prototype. The system model is composed of a TE heat pump element model coupled with a psychrometric dryer sub-model. Experimental results had energy factors (EFs) of up to 2.95 kg of dry cloth per kWh (6.51 lb c/kWh),more » with a dry time of 159 min. A faster dry time of 96 min was also achieved at an EF of 2.54 kg c/kWh (5.60 lb c/kWh). The model was able to replicate the experimental results within 5% of EF and 5% of dry time values. Finally, the results are used to identify important parameters that affect dryer performance, such as relative humidity of air leaving the drum.« less

  14. Experimental evaluation and thermodynamic system modeling of thermoelectric heat pump clothes dryer

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

    Patel, Viral K.; Gluesenkamp, Kyle R.; Goodman, Dakota

    Electric clothes dryers consume about 6% of US residential electricity consumption. Using a solid-state technology without refrigerant, thermoelectric (TE) heat pump dryers have the potential to be more efficient than units based on electric resistance and less expensive than units based on vapor compression. This study presents a steady state TE dryer model, and validates the model against results from an experimental prototype. The system model is composed of a TE heat pump element model coupled with a psychrometric dryer sub-model. Experimental results had energy factors (EFs) of up to 2.95 kg of dry cloth per kWh (6.51 lb c/kWh),more » with a dry time of 159 min. A faster dry time of 96 min was also achieved at an EF of 2.54 kg c/kWh (5.60 lb c/kWh). The model was able to replicate the experimental results within 5% of EF and 5% of dry time values. Finally, the results are used to identify important parameters that affect dryer performance, such as relative humidity of air leaving the drum.« less

  15. Creating Cycling-Friendly Environments for Children: Which Micro-Scale Factors Are Most Important? An Experimental Study Using Manipulated Photographs

    PubMed Central

    Ghekiere, Ariane; Deforche, Benedicte; Mertens, Lieze; De Bourdeaudhuij, Ilse; Clarys, Peter; de Geus, Bas; Cardon, Greet; Nasar, Jack; Salmon, Jo; Van Cauwenberg, Jelle

    2015-01-01

    Background Increasing participation in transportation cycling represents a useful strategy for increasing children’s physical activity levels. Knowledge on how to design environments to encourage adoption and maintenance of transportation cycling is limited and relies mainly on observational studies. The current study experimentally investigates the relative importance of micro-scale environmental factors for children’s transportation cycling, as these micro-scale factors are easier to change within an existing neighborhood compared to macro-scale environmental factors (i.e. connectivity, land-use mix, …). Methods Researchers recruited children and their parents (n = 1232) via 45 randomly selected schools across Flanders and completed an online questionnaire which consisted of 1) demographic questions; and 2) a choice-based conjoint (CBC) task. During this task, participants chose between two photographs which we had experimentally manipulated in seven micro-scale environmental factors: type of cycle path; evenness of cycle path; traffic speed; traffic density; presence of speed bumps; environmental maintenance; and vegetation. Participants indicated which route they preferred to (let their child) cycle along. To find the relative importance of these micro-scale environmental factors, we conducted Hierarchical Bayes analyses. Results Type of cycle path emerged as the most important factor by far among both children and their parents, followed by traffic density and maintenance, and evenness of the cycle path among children. Among parents, speed limits and maintenance emerged as second most important, followed by evenness of the cycle path, and traffic density. Conclusion Findings indicate that improvements in micro-scale environmental factors might be effective for increasing children’s transportation cycling, since they increase the perceived supportiveness of the physical environment for transportation cycling. Investments in creating a clearly designated

  16. Creating Cycling-Friendly Environments for Children: Which Micro-Scale Factors Are Most Important? An Experimental Study Using Manipulated Photographs.

    PubMed

    Ghekiere, Ariane; Deforche, Benedicte; Mertens, Lieze; De Bourdeaudhuij, Ilse; Clarys, Peter; de Geus, Bas; Cardon, Greet; Nasar, Jack; Salmon, Jo; Van Cauwenberg, Jelle

    2015-01-01

    Increasing participation in transportation cycling represents a useful strategy for increasing children's physical activity levels. Knowledge on how to design environments to encourage adoption and maintenance of transportation cycling is limited and relies mainly on observational studies. The current study experimentally investigates the relative importance of micro-scale environmental factors for children's transportation cycling, as these micro-scale factors are easier to change within an existing neighborhood compared to macro-scale environmental factors (i.e. connectivity, land-use mix, …). Researchers recruited children and their parents (n = 1232) via 45 randomly selected schools across Flanders and completed an online questionnaire which consisted of 1) demographic questions; and 2) a choice-based conjoint (CBC) task. During this task, participants chose between two photographs which we had experimentally manipulated in seven micro-scale environmental factors: type of cycle path; evenness of cycle path; traffic speed; traffic density; presence of speed bumps; environmental maintenance; and vegetation. Participants indicated which route they preferred to (let their child) cycle along. To find the relative importance of these micro-scale environmental factors, we conducted Hierarchical Bayes analyses. Type of cycle path emerged as the most important factor by far among both children and their parents, followed by traffic density and maintenance, and evenness of the cycle path among children. Among parents, speed limits and maintenance emerged as second most important, followed by evenness of the cycle path, and traffic density. Findings indicate that improvements in micro-scale environmental factors might be effective for increasing children's transportation cycling, since they increase the perceived supportiveness of the physical environment for transportation cycling. Investments in creating a clearly designated space for the young cyclist, separated from

  17. Expression of β-nerve growth factor and homeobox A10 in experimental cryptorchidism treated with exogenous nerve growth factor.

    PubMed

    Xian, Hua; Xian, Yun; Liu, Lili; Wang, Yongjun; He, Jianghong; Huang, Jianfei

    2015-04-01

    With the exception of standard inguinal orchidopexy, treatment of cryptorchidism with human chorionic gonadotropin has been performed for several years; however, its side effects have limited its application. The β‑nerve growth factor (NGF) and homeobox A10 (HoxA10) genes are closely associated with the development of the testes. To the best of our knowledge, whether exogenous NGF alters the endogenous levels of NGF and HoxA10 in cryptorchidism in rats remains to be elucidated. The aim of the present study was to evaluate the gene and protein expression of NGF and HoxA10 in experimental cryptorchidism following treatment with exogenous NGF. A unilateral mechanical cryptorchidism model in Sprague-Dawley rats was established and different concentrations of exogenous NGF were administered to observe the effects of NGF on cryptorchidism. Changes in the gene and protein expression levels of NGF and HoxA10 in the cryptorchid tissues of each group were identified using one step reverse transcription-quantitative polymerase chain reaction, in situ hybridization with digoxigenin‑labeled‑β‑NGF RNA probes, immunofluorescence and immunohistochemistry, respectively. The expression levels of NGF and HoxA10 were markedly higher in the group treated with a high dose of exogenous NGF compared with the group treated with a low dose of exogenous NGF and the group treated with human chorionic gonadotropin. These results confirmed the potential therapeutic effect of exogenous NGF in human cryptorchidism.

  18. Human Factors Evaluation of Advanced Electric Power Grid Visualization Tools

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

    Greitzer, Frank L.; Dauenhauer, Peter M.; Wierks, Tamara G.

    This report describes initial human factors evaluation of four visualization tools (Graphical Contingency Analysis, Force Directed Graphs, Phasor State Estimator and Mode Meter/ Mode Shapes) developed by PNNL, and proposed test plans that may be implemented to evaluate their utility in scenario-based experiments.

  19. Maintenance of a smoking cessation program in public health clinics beyond the experimental evaluation period.

    PubMed Central

    Manfredi, C.; Crittenden, K.; Cho, Y. I.; Engler, J.; Warnecke, R.

    2001-01-01

    OBJECTIVES: As phase 3 of a study to evaluate a smoking cessation program in public health practice, the authors assess the maintenance and impact of the It's Time smoking cessation program in seven public maternal and child health clinics in Chicago. METHODS: The authors interviewed 404 clinic patients in the study's baseline phase (prior to introduction of the It's Time intervention program), and 610 in the program maintenance phase (in the year after experimental evaluation had ended) to assess exposure to smoking cessation interventions offered at the clinic, and smoking cessation outcomes (quit, actions toward quitting, scores on action, motivation, readiness, and confidence scales). The authors controlled for clustering of smokers within clinics, smokers' characteristics prior to clinic visit, and type of clinic service. They compared outcomes by study group (control or intervention) to which each clinic had been assigned in the earlier experimental phase. RESULTS: Compared to baseline, smokers in the maintenance phase had greater exposure to posters, provider advice and booklet, and better outcomes on seven of eight smoking cessation measures, including quitting. These improvements were larger for clinics with prior experience implementing It's Time. CONCLUSION: Participation in the experimental evaluation of the It's Time program prepared and possibly motivated the clinics to continue the program. Continuing the program resulted in greater delivery of interventions and improved smoking cessation outcomes for smokers in the clinics. PMID:11889280

  20. Design and experimental evaluation of compact radial-inflow turbines

    NASA Technical Reports Server (NTRS)

    Fredmonski, A. J.; Huber, F. W.; Roelke, R. J.; Simonyi, S.

    1991-01-01

    The application of a multistage 3D Euler solver to the aerodynamic design of two compact radial-inflow turbines is presented, along with experimental results evaluating and validating the designs. The objectives of the program were to design, fabricate, and rig test compact radial-inflow turbines with equal or better efficiency relative to conventional designs, while having 40 percent less rotor length than current traditionally-sized radial turbines. The approach to achieving these objectives was to apply a calibrated 3D multistage Euler code to accurately predict and control the high rotor flow passage velocities and high aerodynamic loadings resulting from the reduction in rotor length. A comparison of the advanced compact designs to current state-of-the-art configurations is presented.

  1. Third National Even Start Evaluation: Follow-Up Findings from the Experimental Design Study. NCEE 2005-3002

    ERIC Educational Resources Information Center

    Ricciuti, Anne E., St.Pierre, Robert G.; Lee, Wang; Parsad, Amanda

    2004-01-01

    Citation: Ricciuti, A.E., R.G. St.Pierre, W. Lee, A. Parsad & T. Rimdzius. Third National Even Start Evaluation: Follow-Up Findings From the Experimental Design Study. U.S. Department of Education, Institute of Education Sciences, National Center for Education Evaluation and Regional Assistance. Washington, D.C., 2004. Background: The Even…

  2. In situ impulse test: an experimental and analytical evaluation of data interpretation procedures

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

    Not Available

    1975-08-01

    Special experimental field testing and analytical studies were undertaken at Fort Lawton in Seattle, Washington, to study ''close-in'' wave propagation and evaluate data interpretation procedures for a new in situ impulse test. This test was developed to determine the shear wave velocity and dynamic modulus of soils underlying potential nuclear power plant sites. The test is different from conventional geophysical testing in that the velocity variation with strain is determined for each test. In general, strains between 10/sup -1/ and 10/sup -3/ percent are achieved. The experimental field work consisted of performing special tests in a large test sand fillmore » to obtain detailed ''close-in'' data. Six recording transducers were placed at various points on the energy source, while approximately 37 different transducers were installed within the soil fill, all within 7 feet of the energy source. Velocity measurements were then taken simultaneously under controlled test conditions to study shear wave propagation phenomenology and help evaluate data interpretation procedures. Typical test data are presented along with detailed descriptions of the results.« less

  3. Evaluation of the efficacy of Hylotelephium purpureum gel in the treatment of experimental periodontitis

    PubMed Central

    Wang, Xiaofeng; Wang, Wei; Li, Wei; Niu, Zhiduo; Wang, Qing; Zhang, Dianwen; Li, Hui; Wang, Jincheng

    2018-01-01

    Local drug delivery systems have been proposed for the treatment of periodontitis, and Hylotelephium purpureum may be a suitable agent for use in such a system. The present study aimed to formulate a Hylotelephium purpureum gel (HPG) and evaluate the anti-inflammatory activity and antinociceptive effects of Hylotelephium purpureum and to assess the duration of action and efficacy of HPG in the treatment of experimental periodontitis in a KM mouse model. First, an acute toxicity study was performed, and secondly, xylene-induced mouse-ear edema, acetic acid-induced mouse peritoneal capillary permeability and carrageenan-induced hind-paw edema tests were used to investigate the anti-inflammatory activity of the gel. The acetic acid-induced writhing response and hot-plate tests were used to evaluate the antinociceptive activity. The therapeutic effects of HPG in experimental periodontitis were evaluated and minimum inhibitory concentration of the gel was determined. The results showed that intragastrically administration of 80 ml/kg of HPG produced no toxic effects. There were statistically significant changes in gingival indexes and sulcus bleeding indexes in the high-dose HPG-treated group. The serum levels of superoxide dismutase and glutathione peroxidase were significantly heightened, while the level of malondialdehyde was decreased. HPG exhibited 32.7% inhibition of edema, and altered the peritoneal capillary permeability in mice. The gel had relatively good bacteriostatic and bactericidal effects. It also exhibited antinociceptive activity, as demonstrated by the acetic acid-induced writhing response test and hot-plate test. In summary, the present study demonstrates that HPG is effective in the treatment of experimental periodontitis. PMID:29541459

  4. A novel evaluation method for extrapolated retention factor in determination of n-octanol/water partition coefficient of halogenated organic pollutants by reversed-phase high performance liquid chromatography.

    PubMed

    Han, Shu-ying; Liang, Chao; Qiao, Jun-qin; Lian, Hong-zhen; Ge, Xin; Chen, Hong-yuan

    2012-02-03

    The retention factor corresponding to pure water in reversed-phase high performance liquid chromatography (RP-HPLC), k(w), was commonly obtained by extrapolation of retention factor (k) in a mixture of organic modifier and water as mobile phase in tedious experiments. In this paper, a relationship between logk(w) and logk for directly determining k(w) has been proposed for the first time. With a satisfactory validation, the approach was confirmed to enable easy and accurate evaluation of k(w) for compounds in question with similar structure to model compounds. Eight PCB congeners with different degree of chlorination were selected as a training set for modeling the logk(w)-logk correlation on both silica-based C(8) and C(18) stationary phases to evaluate logk(w) of sample compounds including seven PCB, six PBB and eight PBDE congeners. These eight model PCBs were subsequently combined with seven structure-similar benzene derivatives possessing reliable experimental K(ow) values as a whole training set for logK(ow)-logk(w) regressions on the two stationary phases. Consequently, the evaluated logk(w) values of sample compounds were used to determine their logK(ow) by the derived logK(ow)-logk(w) models. The logK(ow) values obtained by these evaluated logk(w) were well comparable with those obtained by experimental-extrapolated logk(w), demonstrating that the proposed method for logk(w) evaluation in this present study could be an effective means in lipophilicity study of environmental contaminants with numerous congeners. As a result, logK(ow) data of many PCBs, PBBs and PBDEs could be offered. These contaminants are considered to widely exist in the environment, but there have been no reliable experimental K(ow) data available yet. Copyright © 2011 Elsevier B.V. All rights reserved.

  5. Recent mouse and rat methods for the study of experimental oral candidiasis

    PubMed Central

    Costa, Anna CBP; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio OC

    2013-01-01

    The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis. PMID:23715031

  6. Recent mouse and rat methods for the study of experimental oral candidiasis.

    PubMed

    Costa, Anna C B P; Pereira, Cristiane A; Junqueira, Juliana C; Jorge, Antonio O C

    2013-07-01

    The Candida genus expresses virulence factors that, when combined with immunosuppression and other risk factors, can cause different manifestations of oral candidiasis. The treatment of mucosal infections caused by Candida and the elucidation of the disease process have proven challenging. Therefore, the study of experimentally induced oral candidiasis in rats and mice is useful to clarify the etiopathology of this condition, improve diagnosis, and search for new therapeutic options because the disease process in these animals is similar to that of human candidiasis lesions. Here, we describe and discuss new studies involving rat and mouse models of oral candidiasis with respect to methods for inducing experimental infection, methods for evaluating the development of experimental candidiasis, and new treatment strategies for oral candidiasis.

  7. Experimental evaluation of the optical quality of DMD SLM for its application as Fourier holograms displaying device

    NASA Astrophysics Data System (ADS)

    Molodtsov, D. Y.; Cheremkhin, P. A.; Krasnov, V. V.; Rodin, V. G.

    2016-04-01

    In this paper, the optical quality of micromirror DMD spatial light modulator (SLM) is evaluated and its applicability as an output device for holographic filters in dispersive correlators is analyzed. The possibility of using of DMD SLM extracted from consumer DLP-projector was experimentally evaluated by displaying of Fourier holograms. Software for displaying of holograms was developed. Experiments on holograms reconstruction was conducted with a different number of holograms pixels (and different placement on SLM). Reduction of number of pixels of output hologram (i.e. size of minimum resolvable element) led to improvement of reconstructed image quality. The evaluation shows that not every DMD-chip has acceptable optical quality for its application as display device for Fourier holograms. It was determined that major factor of reconstructed image quality degradation is a curvature of surface of SLM or its safety glass. Ranging hologram size allowed to estimate approximate size of sufficiently flat area of SLM matrix. For tested SLM it was about 1.5 mm. Further hologram size increase led to significant reconstructed image quality degradation. Developed and applied a technique allows to quickly estimate maximum size of holograms that can be displayed with specific SLM without significant degradation of reconstructed image. Additionally it allows to identify areas on the SLM with increased curvature of the surface.

  8. Beauty photoproduction at HERA: k{sub T}-factorization versus experimental data

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

    Lipatov, A.V.; Zotov, N.P.

    We present calculations of the beauty photoproduction at HERA collider in the framework of the k{sub T}-factorization approach. Both direct and resolved photon contributions are taken into account. The unintegrated gluon densities in a proton and in a photon are obtained from the full CCFM, from unified BFKL-DGLAP evolution equations as well as from the Kimber-Martin-Ryskin prescription. We investigate different production rates (both inclusive and associated with hadronic jets) and compare our theoretical predictions with the recent experimental data taken by the H1 and ZEUS collaborations. Special attention is put on the x{sub {gamma}}{sup obs} variable which is sensitive tomore » the relative contributions to the beauty production cross section.« less

  9. Human Factors Checklist for the Design and Evaluation of Air Traffic Control Systems

    DOT National Transportation Integrated Search

    1995-04-01

    This document presents human factors issues that should bo considered in tho : design and evaluation of air traffic control (ATC! systoms and subsystems. Tho : checklist is a companion document to Human Factors in tho Design and Evaluation of : Air T...

  10. Evaluating Academic Journals without Impact Factors for Collection Management Decisions.

    ERIC Educational Resources Information Center

    Dilevko, Juris; Atkinson, Esther

    2002-01-01

    Discussion of evaluating academic journals for collection management decisions focuses on a methodological framework for evaluating journals not ranked by impact factors in Journal Citation Reports. Compares nonranked journals with ranked journals and then applies this framework to a case study in the field of medical science. (LRW)

  11. Effect of centrifugation time on growth factor and MMP release of an experimental platelet-rich fibrin-type product.

    PubMed

    Eren, Gülnihal; Gürkan, Ali; Atmaca, Harika; Dönmez, Ayhan; Atilla, Gül

    2016-07-01

    Platelet-rich fibrin (PRF) has a controlled release of growth factors due to the fibrin matrix structure. Different centrifugation protocols were suggested for PRF preparation. Since the derivation method of PRF can alter its contents, in the present study it is aimed to investigate the cell contents and transforming growth factor beta-1 (TGF-β1), platelet-derived growth factor (PDGF-AB), vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-1 and-8 release from experimental PRF-type membranes obtained with different centrifugation times at 400 gravity. Three blood samples were collected from 20 healthy non-smoker volunteers. One tube was used for whole blood analyses. The other two tubes were centrifuged at 400 g for 10 minutes (group A) or 12 minutes (group B). Each experimental PRF-type membrane was placed in Dulbecco's Modified Eagle's Medium (DMEM)and at 1, 24 and 72 hours, TGF-β1, PDGF-AB, VEGF, MMP-1 and -8 release amounts were analysed by enzyme-linked immunosorbent assay (ELISA). The blood cell count of membranes was determined by subtracting plasma supernatant and red blood cell (RBC) mixture from the whole blood cell counts. At 72 hours, the VEGF level of group B was statistically higher than that of group A (p = 0.040). The centrifugation time was not found to influence the release of other growth factors, enzymes and cell counts. Within the limits of the present study, it might be suggested that centrifugation time at a constant gravity has a significant effect on the VEGF levels released from experimental PRF-type membrane. It can be concluded that due to the importance of VEGF in the tissue healing process, membranes obtained at 12-minute centrifugation time may show a superior potential in wound healing.

  12. Experimental evaluation of reproductive response to climate warming in an oviparous skink.

    PubMed

    Lu, Hongliang; Wang, Yong; Tang, Wenqi; DU, Weiguo

    2013-06-01

    The impact of climate warming on organisms is increasingly being recognized. The experimental evaluation of phenotypically plastic responses to warming is a critical step in understanding the biological effects and adaptive capacity of organisms to future climate warming. Oviparous Scincella modesta live in deeply-shaded habitats and they require low optimal temperatures during embryonic development, which makes them suitable subjects for testing the effects of warming on reproduction. We raised adult females and incubated their eggs under different thermal conditions that mimicked potential climate warming. Female reproduction, embryonic development and hatchling traits were monitored to evaluate the reproductive response to warming. Experimental warming induced females to lay eggs earlier, but it did not affect the developmental stage of embryos at oviposition or the reproductive output. The high temperatures experienced by gravid females during warming treatments reduced the incubation period and increased embryonic mortality. The locomotor performance of hatchlings was not affected by the maternal thermal environment, but it was affected by the warming treatment during embryonic development. Our results suggest that climate warming might have a profound effect on fitness-relevant traits both at embryonic and post-embryonic stages in oviparous lizards. © 2012 Wiley Publishing Asia Pty Ltd, ISZS and IOZ/CAS.

  13. An experimental evaluation of the performance deficit of an aircraft engine starter turbine

    NASA Technical Reports Server (NTRS)

    Haas, J. E.; Roelke, R. J.; Hermann, P.

    1980-01-01

    An experimental investigation is presented to determine the aerodynamic performance deficit of a 13.5 - centimeter-tip-diameter aircraft engine starter turbine. The two-phased evaluation comprised both the stator and the stage performance, and the experimental design is described in detail. Data obtained from the investigation of three honeycomb shrouds clearly showed that the filled honeycomb reached a total efficiency of 0.868, 8.2 points higher than the open honeycomb shroud, at design equivalent conditions of speed and blade-jet speed ratio. It was concluded that the use of an open honeycomb shroud caused the large performance deficit for the starter turbine. Further research is suggested to ascertain stator inlet boundary layer measurements.

  14. Norming of Student Evaluations of Instruction: Impact of Noninstructional Factors

    ERIC Educational Resources Information Center

    Nargundkar, Satish; Shrikhande, Milind

    2014-01-01

    Student Evaluations of Instruction (SEIs) from about 6,000 sections over 4 years representing over 100,000 students at the college of business at a large public university are analyzed, to study the impact of noninstructional factors on student ratings. Administrative factors like semester, time of day, location, and instructor attributes like…

  15. Prefabricated bone flap: an experimental study comparing deep-frozen and lyophilized-demineralized allogenic bones and tissue expression of transforming growth factor β.

    PubMed

    Rodrigues, Leandro; dos Reis, Luciene Machado; Denadai, Rafael; Raposo-Amaral, Cassio Eduardo; Alonso, Nivaldo; Ferreira, Marcus Castro; Jorgetti, Vanda

    2013-11-01

    Extensive bone defects are still a challenge for reconstructive surgery. Allogenic bones can be an alternative with no donor area morbidity and unlimited amount of tissue. Better results can be achieved after allogenic bone preparation and adding a vascular supply, which can be done along with flap prefabrication. The purpose of this study was to evaluate demineralized/lyophilized and deep-frozen allogenic bones used for flap prefabrication and the tissue expression of transforming growth factor β (TGF-β) in these bone fragments. Fifty-six Wistar rat bone diaphyses were prepared and distributed in 4 groups: demineralized/lyophilized (experimental group 1 and control group 2) and deep freezing (experimental group 3 and control group 4). Two bone segments (one of each group) were implanted in rats to prefabricate flaps using superficial epigastric vessels (experimental groups) or only transferred as grafts (control groups). These fragments remained in their respective inguinal regions until the death that occurred at 2, 4, and 6 weeks after the operation. Semiquantitative histologic (tetracycline marking, cortical resorption, number of giant cells, and vascularization) and histomorphometrical quantitative (osteoid thickness, cortical thickness, and fibrosis thickness) analyses were performed. Transforming growth factor β immunohistochemistry staining was also performed. Group 1 fragments presented an osteoid matrix on their external surface in all periods. Cartilage formation and mineralization areas were also noticed. These findings were not observed in group 3 fragments. Group 1 had more mineralization and double tetracycline marks, which were almost not seen in group 3. Cortical resorption and the number of giant cells were greater in group 3 in all periods. Vascularization and fibrosis thickness were similar in both experimental groups. Group 1 had more intense TGF-β staining within 2 weeks of study. Nevertheless, from 4 weeks onward, group 3 presented

  16. A human factors evaluation of the operational demonstration flight inspection aircraft.

    DOT National Transportation Integrated Search

    1995-05-01

    These reports describe the data collection and analysis efforts performed by the Civil Aerospace Medical Institute's Human Factors Research Laboratory to assist the Office of Aviation System Standards (AVN) in the human factors evaluation of the Oper...

  17. A Contextual Factors Framework to Inform Implementation and Evaluation of Public Health Initiatives

    ERIC Educational Resources Information Center

    Vanderkruik, Rachel; McPherson, Marianne E.

    2017-01-01

    Evaluating initiatives implemented across multiple settings can elucidate how various contextual factors may influence both implementation and outcomes. Understanding context is especially critical when the same program has varying levels of success across settings. We present a framework for evaluating contextual factors affecting an initiative…

  18. Driver crash risk factors and prevalence evaluation using naturalistic driving data.

    PubMed

    Dingus, Thomas A; Guo, Feng; Lee, Suzie; Antin, Jonathan F; Perez, Miguel; Buchanan-King, Mindy; Hankey, Jonathan

    2016-03-08

    The accurate evaluation of crash causal factors can provide fundamental information for effective transportation policy, vehicle design, and driver education. Naturalistic driving (ND) data collected with multiple onboard video cameras and sensors provide a unique opportunity to evaluate risk factors during the seconds leading up to a crash. This paper uses a National Academy of Sciences-sponsored ND dataset comprising 905 injurious and property damage crash events, the magnitude of which allows the first direct analysis (to our knowledge) of causal factors using crashes only. The results show that crash causation has shifted dramatically in recent years, with driver-related factors (i.e., error, impairment, fatigue, and distraction) present in almost 90% of crashes. The results also definitively show that distraction is detrimental to driver safety, with handheld electronic devices having high use rates and risk.

  19. Driver crash risk factors and prevalence evaluation using naturalistic driving data

    PubMed Central

    Dingus, Thomas A.; Guo, Feng; Lee, Suzie; Antin, Jonathan F.; Perez, Miguel; Buchanan-King, Mindy; Hankey, Jonathan

    2016-01-01

    The accurate evaluation of crash causal factors can provide fundamental information for effective transportation policy, vehicle design, and driver education. Naturalistic driving (ND) data collected with multiple onboard video cameras and sensors provide a unique opportunity to evaluate risk factors during the seconds leading up to a crash. This paper uses a National Academy of Sciences-sponsored ND dataset comprising 905 injurious and property damage crash events, the magnitude of which allows the first direct analysis (to our knowledge) of causal factors using crashes only. The results show that crash causation has shifted dramatically in recent years, with driver-related factors (i.e., error, impairment, fatigue, and distraction) present in almost 90% of crashes. The results also definitively show that distraction is detrimental to driver safety, with handheld electronic devices having high use rates and risk. PMID:26903657

  20. Interviewer as Instrument: Accounting for Human Factors in Evaluation Research

    ERIC Educational Resources Information Center

    Brown, Joel H.

    2006-01-01

    This methodological study examines an original data collection model designed to incorporate human factors and enhance data richness in qualitative and evaluation research. Evidence supporting this model is drawn from in-depth youth and adult interviews in one of the largest policy/program evaluations undertaken in the United States, the Drug,…

  1. Experimental Evaluation of Behavioral Activation Treatment of Anxiety (BATA) in Three Older Adults

    ERIC Educational Resources Information Center

    Turner, Jarrod S.; Leach, David J.

    2010-01-01

    This report describes three single-case experimental evaluations of Behavioral Activation Treatment of Anxiety (BATA) applied with a 51-year-old male, a 62-year-old female, and a 53-year-old female, each of whom met DSM-IV criteria for anxiety. Each case was a clinical replication of an initial trial of BATA reported in Turner and Leach (2009).…

  2. Experimental evaluation of HJB optimal controllers for the attitude dynamics of a multirotor aerial vehicle.

    PubMed

    Prado, Igor Afonso Acampora; Pereira, Mateus de Freitas Virgílio; de Castro, Davi Ferreira; Dos Santos, Davi Antônio; Balthazar, Jose Manoel

    2018-06-01

    The present paper is concerned with the design and experimental evaluation of optimal control laws for the nonlinear attitude dynamics of a multirotor aerial vehicle. Three design methods based on Hamilton-Jacobi-Bellman equation are taken into account. The first one is a linear control with guarantee of stability for nonlinear systems. The second and third are a nonlinear suboptimal control techniques. These techniques are based on an optimal control design approach that takes into account the nonlinearities present in the vehicle dynamics. The stability Proof of the closed-loop system is presented. The performance of the control system designed is evaluated via simulations and also via an experimental scheme using the Quanser 3-DOF Hover. The experiments show the effectiveness of the linear control method over the nonlinear strategy. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  3. Human factors requirements for telerobotic command and control: The European Space Agency experimental programme

    NASA Technical Reports Server (NTRS)

    Stone, Robert J.

    1991-01-01

    Space Telerobotics research, performed under contract to the European Space Agency (ESA), concerning the execution of human factors experiments, and ultimately leading to the development of a telerobotics test bed, has been carried out since 1985 by a British Consortium consisting of British Aerospace, the United Kingdom Atomic Energy Authority and, more recently, the UK National Advanced Robotics Research Centre. The principal aim of the first study of the series was to derive preliminary requirements for a teleoperation servicing system, with reference to two mission model scenarios. The first scenario introduced the problem of communications time delays, and their likely effect on the ground-based operator in control of a manipulator system on board an unmanned servicing vehicle in Low Earth Orbit. In the second scenario, the operator was located on the NASA Orbiter aft flight deck, supervising the control of a prototype manipulator in the 'servicing' of an experimental payload in the cargo bay area. Human factors analyses centered on defining the requirements for the teleoperator workstation, such as identifying basic ergonomic requirements for workstation and panel layouts, defining teleoperation strategies, developing alphanumeric and graphic screen formats for the supervision or direct control of the manipulator, and the potential applications of expert system technology. The second study for ESA involved an experimental appraisal of some of the important issues highlighted in the first study, for which relevant human factors data did not exist. Of central importance during the second study was the issue of communications time delays and their effect on the manual control of a teleoperated manipulator from a ground-based command and control station.

  4. 48 CFR 215.304 - Evaluation factors and significant subfactors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... of any information technology, whether acquired as a service or as a supply, consider the need for an evaluation factor regarding supply chain risk (see subpart 239.73). [71 FR 3414, Jan. 23, 2006, as amended at...

  5. Experimental determination of pCo perturbation factors for plane-parallel chambers

    NASA Astrophysics Data System (ADS)

    Kapsch, R. P.; Bruggmoser, G.; Christ, G.; Dohm, O. S.; Hartmann, G. H.; Schüle, E.

    2007-12-01

    For plane-parallel chambers used in electron dosimetry, modern dosimetry protocols recommend a cross-calibration against a calibrated cylindrical chamber. The rationale for this is the unacceptably large (up to 3-4%) chamber-to-chamber variations of the perturbation factors (pwall)Co, which have been reported for plane-parallel chambers of a given type. In some recent publications, it was shown that this is no longer the case for modern plane-parallel chambers. The aims of the present study are to obtain reliable information about the variation of the perturbation factors for modern types of plane-parallel chambers, and—if this variation is found to be acceptably small—to determine type-specific mean values for these perturbation factors which can be used for absorbed dose measurements in electron beams using plane-parallel chambers. In an extensive multi-center study, the individual perturbation factors pCo (which are usually assumed to be equal to (pwall)Co) for a total of 35 plane-parallel chambers of the Roos type, 15 chambers of the Markus type and 12 chambers of the Advanced Markus type were determined. From a total of 188 cross-calibration measurements, variations of the pCo values for different chambers of the same type of at most 1.0%, 0.9% and 0.6% were found for the chambers of the Roos, Markus and Advanced Markus types, respectively. The mean pCo values obtained from all measurements are \\bar{p}^Roos_Co = 1.0198, \\bar{p}^Markus_Co = 1.0175 and \\bar{p}^Advanced_Co = 1.0155 ; the relative experimental standard deviation of the individual pCo values is less than 0.24% for all chamber types; the relative standard uncertainty of the mean pCo values is 1.1%.

  6. Experimental re-evaluation of flunarizine as add-on antiepileptic therapy.

    PubMed

    Thakur, Anamika; Sahai, A K; Thakur, J S

    2011-04-01

    Experimental studies have found several calcium channel blockers with anticonvulsant property. Flunarizine is one of the most potent calcium channel blockers, which has shown anticonvulsant effect against pentylenetetrazole (PTZ) and maximal electroshock (MES)-induced seizures. However, further experimental and clinical trials have shown varied results. We conducted a PTZ model experimental study to re-evaluate the potential of flunarizine for add-on therapy in the management of refractory epilepsy. Experiments were conducted in PTZ model involving Swiss strain mice. Doses producing seizures in 50% and 99% mice, i.e. CD(50) and CD(99) values of PTZ were obtained from the dose-response study. Animals received graded, single dose of sodium valproate (100-300 mg/kg), lamotrigine (3-12 mg/kg) and flunarizine (5-20 mg/kg), and then each group of mice was injected with CD(99) dose of PTZ (65mg/kg i.p.). Another group of mice received single ED(50) dose (dose producing seizure protection in 50% mice) of sodium valproate and flunarizine separately in left and right side of abdomen. Results were analysed by Kruskal-Wallis ANOVA on Ranks test. As compared to control, sodium valproate at 250 mg/kg and 300 mg/kg produced statistical significant seizure protection. At none of the pre-treatment dose levels of lamotrigine, the seizure score with PTZ differed significantly from that observed in the vehicle-treated group. Pre-treatment with flunarizine demonstrated dose-dependent decrease in the seizure score to PTZ administration. As compared to control group, flunarizine at 20 mg/kg produced statistical significant seizure protection. As combined use of sodium valproate and flunarizine has shown significant seizure protection in PTZ model, flunarizine has a potential for add-on therapy in refractory cases of partial seizures. It is therefore, we conclude that further experimental studies and multicenter clinical trials involving large sample size are needed to establish

  7. An experimental evaluation of fire history reconstruction using dendrochronology in white oak (Quercus alba)

    Treesearch

    Ryan W. McEwan; Todd F. Hutchinson; Robert D. Ford; Brian C. McCarthy

    2007-01-01

    Dendrochronological analysis of fire scars on tree cross sections has been critically important for understanding historical fire regimes and has influenced forest management practices. Despite its value as a tool for understanding historical ecosystems, tree-ring-based fire history reconstruction has rarely been experimentally evaluated. To examine the efficacy of...

  8. Towards satisfying performance of an O/W cosmetic emulsion: screening of reformulation factors on textural and rheological properties using general experimental design.

    PubMed

    Filipovic, M; Lukic, M; Djordjevic, S; Krstonosic, V; Pantelic, I; Vuleta, G; Savic, S

    2017-10-01

    Consumers' demand for improved products' performance, alongside with the obligation of meeting the safety and efficacy goals, presents a key reason for the reformulation, as well as a challenging task for formulators. Any change of the formulation, whether it is wanted - in order to innovate the product (new actives and raw materials) or necessary - due to, for example legislative changes (restriction of ingredients), ingredients market unavailability, new manufacturing equipment, may have a number of consequences, desired or otherwise. The aim of the study was to evaluate the influence of multiple factors - variations of the composition, manufacturing conditions and their interactions, on emulsion textural and rheological characteristics, applying the general experimental factorial design and, subsequently, to establish the approach that could replace, to some extent, certain expensive and time-consuming tests (e.g. certain sensory analysis), often required, partly or completely, after the reformulation. An experimental design strategy was utilized to reveal the influence of reformulation factors (addition of new actives, preparation method change) on textural and rheological properties of cosmetic emulsions, especially those linked to certain sensorial attributes, and droplet size. The general experimental factorial design revealed a significant direct effect of each factor, as well as their interaction effects, on certain characteristics of the system and provided some valuable information necessary for fine-tuning reformulation conditions. Upon addition of STEM-liposomes, consistency, index of viscosity, firmness and cohesiveness were decreased, as along with certain rheology parameters (elastic and viscous modulus), whereas maximal and minimal apparent viscosities and droplet size were increased. The presence of an emollient (squalene) affected all the investigated parameters in a concentration-dependent manner. Modification of the preparation method (using

  9. Mitochondrial protection by low doses of insulin-like growth factor-Iin experimental cirrhosis

    PubMed Central

    Pérez, Raquel; García-Fernández, María; Díaz-Sánchez, Matías; Puche, Juan E; Delgado, Gloria; Conchillo, Marian; Muntané, Jordi; Castilla-Cortázar, Inma

    2008-01-01

    AIM: To characterize the mitochondrial dysfunction in experimental cirrhosis and to study whether insulin-like growth factor-I(IGF-I) therapy (4 wk) is able to induce beneficial effects on damaged mitochondria leading to cellular protection. METHODS: Wistar rats were divided into three groups: Control group, untreated cirrhotic rats and cirrhotic rats treated with IGF-Itreatment (2 μg/100 g bw/d). Mitochondrial function was analyzed by flow cytometry in isolated hepatic mitochondria, caspase 3 activation was assessed by Western blot and apoptosis by TUNEL in the three experimental groups. RESULTS: Untreated cirrhotic rats showed a mitochondrial dysfunction characterized by a significant reduction of mitochondrial membrane potential (in status 4 and 3); an increase of intramitochondrial reactive oxigen species (ROS) generation and a significant reduction of ATPase activity. IGF-Itherapy normalized mitochondrial function by increasing the membrane potential and ATPase activity and reducing the intramitochondrial free radical production. Activity of the electron transport complexes Iand III was increased in both cirrhotic groups. In addition, untreated cirrhotic rats showed an increase of caspase 3 activation and apoptosis. IGF-Itherapy reduced the expression of the active peptide of caspase 3 and resulted in reduced apoptosis. CONCLUSION: These results show that IGF-Iexerts a mitochondrial protection in experimental cirrhosis leading to reduced apoptosis and increased ATP production. PMID:18461658

  10. An analytical and experimental evaluation of the plano-cylindrical Fresnel lens solar concentrator

    NASA Technical Reports Server (NTRS)

    Hastings, L. J.; Allums, S. L.; Cosby, R. M.

    1976-01-01

    Plastic Fresnel lenses for solar concentration are attractive because of potential for low-cost mass production. An analytical and experimental evaluation of line-focusing Fresnel lenses with application potential in the 200 to 370 C range is reported. Analytical techniques were formulated to assess the solar transmission and imaging properties of a grooves-down lens. Experimentation was based primarily on a 56 cm-wide lens with f-number 1.0. A sun-tracking heliostat provided a non-moving solar source. Measured data indicated more spreading at the profile base than analytically predicted. The measured and computed transmittances were 85 and 87% respectively. Preliminary testing with a second lens (1.85 m) indicated that modified manufacturing techniques corrected the profile spreading problem.

  11. Satisfiers and Dissatisfiers: A Two-Factor Model for Website Design and Evaluation.

    ERIC Educational Resources Information Center

    Zhang, Ping; von Dran, Gisela M.

    2000-01-01

    Investigates Web site design factors and their impact from a theoretical perspective. Presents a two-factor model that can guide Web site design and evaluation. According to the model, there are two types of design factors: hygiene and motivator. Results showed that the two-factor model provides a means for Web-user interface studies. Provides…

  12. Evaluation of a combined lifestyle intervention for overweight and obese patients in primary health care: a quasi-experimental design.

    PubMed

    Verberne, Lisa D M; Hendriks, Marike R C; Rutten, Geert M; Spronk, Inge; Savelberg, Hans H C M; Veenhof, Cindy; Nielen, Mark M J

    2016-12-01

    Combined lifestyle interventions (CLIs) are designed to reduce risk factors for lifestyle-related diseases through increasing physical activity and improvement of dietary behaviour. To evaluate the effects of a CLI for overweight and obese patients on lifestyle-related risk factors and health care consumption, in comparison to usual care. Data on anthropometric and metabolic measurements, morbidity, drugs prescriptions and general practitioner (GP) consultations were extracted from electronic health records (timeframe: July 2009-August 2013). Using a quasi-experimental design, health outcomes of 127 patients who participated in a 1-year CLI were compared to a group of 254 matched patients that received usual care. Baseline to post-intervention changes in health outcomes between intervention and comparison group were evaluated using mixed model analyses. Compared to baseline, both groups showed reductions in body mass index (BMI), blood pressure, total cholesterol and low density lipoprotein cholesterol in year post-intervention. For these outcome measures, no significant differences in changes were observed between intervention and comparison group. A significant improvement of 0.08 mmol/l in high density lipoprotein (HDL) cholesterol was observed for the intervention group above the comparison group (P < 0.01). No significant intergroup differences were shown in drugs prescriptions and number of GP consultations. A CLI for overweight and obese patients in primary health care resulted in similar effects on health outcomes compared to usual care. Only an improvement on HDL cholesterol was shown. This study indicates that implementation and evaluation of a lifestyle intervention in primary health care is challenging due to political and financial barriers. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Development and experimental qualification of a calculation scheme for the evaluation of gamma heating in experimental reactors. Application to MARIA and Jules Horowitz (JHR) MTR Reactors

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

    Tarchalski, M.; Pytel, K.; Wroblewska, M.

    2015-07-01

    Precise computational determination of nuclear heating which consists predominantly of gamma heating (more than 80 %) is one of the challenges in material testing reactor exploitation. Due to sophisticated construction and conditions of experimental programs planned in JHR it became essential to use most accurate and precise gamma heating model. Before the JHR starts to operate, gamma heating evaluation methods need to be developed and qualified in other experimental reactor facilities. This is done inter alia using OSIRIS, MINERVE or EOLE research reactors in France. Furthermore, MARIA - Polish material testing reactor - has been chosen to contribute to themore » qualification of gamma heating calculation schemes/tools. This reactor has some characteristics close to those of JHR (beryllium usage, fuel element geometry). To evaluate gamma heating in JHR and MARIA reactors, both simulation tools and experimental program have been developed and performed. For gamma heating simulation, new calculation scheme and gamma heating model of MARIA have been carried out using TRIPOLI4 and APOLLO2 codes. Calculation outcome has been verified by comparison to experimental measurements in MARIA reactor. To have more precise calculation results, model of MARIA in TRIPOLI4 has been made using the whole geometry of the core. This has been done for the first time in the history of MARIA reactor and was complex due to cut cone shape of all its elements. Material composition of burnt fuel elements has been implemented from APOLLO2 calculations. An experiment for nuclear heating measurements and calculation verification has been done in September 2014. This involved neutron, photon and nuclear heating measurements at selected locations in MARIA reactor using in particular Rh SPND, Ag SPND, Ionization Chamber (all three from CEA), KAROLINA calorimeter (NCBJ) and Gamma Thermometer (CEA/SCK CEN). Measurements were done in forty points using four channels. Maximal nuclear heating

  14. Experimental evaluation of achromatic phase shifters for mid-infrared starlight suppression.

    PubMed

    Gappinger, Robert O; Diaz, Rosemary T; Ksendzov, Alexander; Lawson, Peter R; Lay, Oliver P; Liewer, Kurt M; Loya, Frank M; Martin, Stefan R; Serabyn, Eugene; Wallace, James K

    2009-02-10

    Phase shifters are a key component of nulling interferometry, one of the potential routes to enabling the measurement of faint exoplanet spectra. Here, three different achromatic phase shifters are evaluated experimentally in the mid-infrared, where such nulling interferometers may someday operate. The methods evaluated include the use of dispersive glasses, a through-focus field inversion, and field reversals on reflection from antisymmetric flat-mirror periscopes. All three approaches yielded deep, broadband, mid-infrared nulls, but the deepest broadband nulls were obtained with the periscope architecture. In the periscope system, average null depths of 4x10(-5) were obtained with a 25% bandwidth, and 2x10(-5) with a 20% bandwidth, at a central wavelength of 9.5 mum. The best short term nulls at 20% bandwidth were approximately 9x10(-6), in line with error budget predictions and the limits of the current generation of hardware.

  15. An experimental evaluation of the performance deficit of an aircraft engine starter turbine

    NASA Technical Reports Server (NTRS)

    Hass, J. E.; Roelke, R. J.; Hermann, P.

    1980-01-01

    An experimental investigation was made to determine the reasons for the low aerodynamic performance of a 13.5 centimeter tip diameter aircraft engine starter turbine. The investigation consisted of an evaluation of both the stator and the stage. An approximate ten percent improvement in turbine efficiency was obtained when the honeycomb shroud over the rotor blade tips was filled to obtain a solid shroud surface.

  16. Evaluation of advanced materials through experimental mechanics and modelling

    NASA Technical Reports Server (NTRS)

    Yang, Yii-Ching

    1993-01-01

    Composite materials have been frequently used in aerospace vehicles. Very often defects are inherited during the manufacture and damages are inherited during the construction and services. It becomes critical to understand the mechanical behavior of such composite structure before it can be further used. One good example of these composite structures is the cylindrical bottle of solid rocket motor case with accidental impact damages. Since the replacement of this cylindrical bottle is expensive, it is valuable to know how the damages affects the material, and how it can be repaired. To reach this goal, the damage must be characterized and the stress/strain field must be carefully analyzed. First the damage area, due to impact, is surveyed and identified with a shearography technique which uses the principle of speckle shearing interferometry to measure displacement gradient. Within the damage area of a composite laminate, such as the bottle of solid rocket motor case, all layers are considered to be degraded. Once a lamina being degraded the stiffness as well as strength will be drastically decreased. It becomes a critical area of failure to the whole bottle. And hence the stress/strain field within and around a damage should be accurately evaluated for failure prediction. To investigate the stress/strain field around damages a Hybrid-Numerical method which combines experimental measurement and finite element analysis is used. It is known the stress or strain at the singular point can not be accurately measured by an experimental technique. Nevertheless, if the location is far away from the singular spot, the displacement can be found accurately. Since it reflects the true displacement field locally regardless of the boundary conditions, it is an excellent input data for a finite element analysis to replace the usually assumed boundary conditions. Therefore, the Hybrid-Numerical method is chosen to avoid the difficulty and to take advantage of both experimental

  17. 48 CFR 247.301-71 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Evaluation factor or subfactor. 247.301-71 Section 247.301-71 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply...

  18. 48 CFR 247.301-71 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Evaluation factor or subfactor. 247.301-71 Section 247.301-71 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply...

  19. 48 CFR 247.301-71 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Evaluation factor or subfactor. 247.301-71 Section 247.301-71 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply...

  20. 48 CFR 247.301-71 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Evaluation factor or subfactor. 247.301-71 Section 247.301-71 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply...

  1. 48 CFR 247.301-71 - Evaluation factor or subfactor.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Evaluation factor or subfactor. 247.301-71 Section 247.301-71 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CONTRACT MANAGEMENT TRANSPORTATION Transportation in Supply...

  2. Combined experimental and numerical evaluation of a prototype nano-PCM enhanced wallboard

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

    Biswas, Kaushik; LuPh.D., Jue; Soroushian, Parviz

    2014-01-01

    In the United States, forty-eight (48) percent of the residential end-use energy consumption is spent on space heating and air conditioning. Reducing envelope-generated heating and cooling loads through application of phase change material (PCM)-enhanced building envelopes can facilitate maximizing the energy efficiency of buildings. Combined experimental testing and numerical modeling of PCM-enhanced envelope components are two important aspects of the evaluation of their energy benefits. An innovative phase change material (nano-PCM) was developed with PCM encapsulated with expanded graphite (interconnected) nanosheets, which is highly conductive for enhanced thermal storage and energy distribution, and is shape-stable for convenient incorporation into lightweightmore » building components. A wall with cellulose cavity insulation and prototype PCM-enhanced interior wallboards was built and tested in a natural exposure test (NET) facility in a hot-humid climate location. The test wall contained PCM wallboards and regular gypsum wallboard, for a side-by-side annual comparison study. Further, numerical modeling of the walls containing the nano-PCM wallboard was performed to determine its actual impact on wall-generated heating and cooling loads. The model was first validated using experimental data, and then used for annual simulations using Typical Meteorological Year (TMY3) weather data. This article presents the measured performance and numerical analysis evaluating the energy-saving potential of the nano-PCM-enhanced wallboard.« less

  3. Evaluating the quality of a cell counting measurement process via a dilution series experimental design.

    PubMed

    Sarkar, Sumona; Lund, Steven P; Vyzasatya, Ravi; Vanguri, Padmavathy; Elliott, John T; Plant, Anne L; Lin-Gibson, Sheng

    2017-12-01

    Cell counting measurements are critical in the research, development and manufacturing of cell-based products, yet determining cell quantity with accuracy and precision remains a challenge. Validating and evaluating a cell counting measurement process can be difficult because of the lack of appropriate reference material. Here we describe an experimental design and statistical analysis approach to evaluate the quality of a cell counting measurement process in the absence of appropriate reference materials or reference methods. The experimental design is based on a dilution series study with replicate samples and observations as well as measurement process controls. The statistical analysis evaluates the precision and proportionality of the cell counting measurement process and can be used to compare the quality of two or more counting methods. As an illustration of this approach, cell counting measurement processes (automated and manual methods) were compared for a human mesenchymal stromal cell (hMSC) preparation. For the hMSC preparation investigated, results indicated that the automated method performed better than the manual counting methods in terms of precision and proportionality. By conducting well controlled dilution series experimental designs coupled with appropriate statistical analysis, quantitative indicators of repeatability and proportionality can be calculated to provide an assessment of cell counting measurement quality. This approach does not rely on the use of a reference material or comparison to "gold standard" methods known to have limited assurance of accuracy and precision. The approach presented here may help the selection, optimization, and/or validation of a cell counting measurement process. Published by Elsevier Inc.

  4. Experimental design for evaluating WWTP data by linear mass balances.

    PubMed

    Le, Quan H; Verheijen, Peter J T; van Loosdrecht, Mark C M; Volcke, Eveline I P

    2018-05-15

    A stepwise experimental design procedure to obtain reliable data from wastewater treatment plants (WWTPs) was developed. The proposed procedure aims at determining sets of additional measurements (besides available ones) that guarantee the identifiability of key process variables, which means that their value can be calculated from other, measured variables, based on available constraints in the form of linear mass balances. Among all solutions, i.e. all possible sets of additional measurements allowing the identifiability of all key process variables, the optimal solutions were found taking into account two objectives, namely the accuracy of the identified key variables and the cost of additional measurements. The results of this multi-objective optimization problem were represented in a Pareto-optimal front. The presented procedure was applied to a full-scale WWTP. Detailed analysis of the relation between measurements allowed the determination of groups of overlapping mass balances. Adding measured variables could only serve in identifying key variables that appear in the same group of mass balances. Besides, the application of the experimental design procedure to these individual groups significantly reduced the computational effort in evaluating available measurements and planning additional monitoring campaigns. The proposed procedure is straightforward and can be applied to other WWTPs with or without prior data collection. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Correction factors for self-selection when evaluating screening programmes.

    PubMed

    Spix, Claudia; Berthold, Frank; Hero, Barbara; Michaelis, Jörg; Schilling, Freimut H

    2016-03-01

    In screening programmes there is recognized bias introduced through participant self-selection (the healthy screenee bias). Methods used to evaluate screening programmes include Intention-to-screen, per-protocol, and the "post hoc" approach in which, after introducing screening for everyone, the only evaluation option is participants versus non-participants. All methods are prone to bias through self-selection. We present an overview of approaches to correct for this bias. We considered four methods to quantify and correct for self-selection bias. Simple calculations revealed that these corrections are actually all identical, and can be converted into each other. Based on this, correction factors for further situations and measures were derived. The application of these correction factors requires a number of assumptions. Using as an example the German Neuroblastoma Screening Study, no relevant reduction in mortality or stage 4 incidence due to screening was observed. The largest bias (in favour of screening) was observed when comparing participants with non-participants. Correcting for bias is particularly necessary when using the post hoc evaluation approach, however, in this situation not all required data are available. External data or further assumptions may be required for estimation. © The Author(s) 2015.

  6. Experimental system for the control of surgically induced infections

    NASA Technical Reports Server (NTRS)

    Tevebaugh, M. D.

    1971-01-01

    The development tests to be performed on the experimental system are described in detail. The test equipment, conditions, and procedures are given. The portable clean room tests include assembly, collapsability, portability, and storage; laminar flow rate; static pressure; air flow pattern; and electrostatic buildup. The other tests are on the ventilation system, human factors evaluation, electrical subsystem, and material compatibility.

  7. How do environmental factors influence life cycles and development? An experimental framework for early-diverging metazoans

    PubMed Central

    Bosch, Thomas C. G.; Adamska, Maja; Augustin, René; Domazet-Loso, Tomislav; Foret, Sylvain; Fraune, Sebastian; Funayama, Noriko; Grasis, Juris; Hamada, Mayuko; Hatta, Masayuki; Hobmayer, Bert; Kawai, Kotoe; Klimovich, Alexander; Manuel, Michael; Shinzato, Chuya; Technau, Uli; Yum, Seungshic; Miller, David J.

    2014-01-01

    Ecological developmental biology (eco-devo) explores the mechanistic relationships between the processes of individual development and environmental factors. Recent studies imply that some of these relationships have deep evolutionary origins, and may even predate the divergences of the simplest extant animals, including cnidarians and sponges. Development of these early diverging metazoans is often sensitive to environmental factors, and these interactions occur in the context of conserved signaling pathways and mechanisms of tissue homeostasis whose detailed molecular logic remain elusive. Efficient methods for transgenesis in cnidarians together with the ease of experimental manipulation in cnidarians and sponges make them ideal models for understanding causal relationships between environmental factors and developmental mechanisms. Here, we identify major questions at the interface between animal evolution and development and outline a road map for research aimed at identifying the mechanisms that link environmental factors to developmental mechanisms in early diverging metazoans. PMID:25205353

  8. EVALUATION OF TWO METHODS FOR PREDICTION OF BIOACCUMULATION FACTORS

    EPA Science Inventory

    Two methods for deriving bioaccumulation factors (BAFs) used by the U.S. Environmental Protection Agency (EPA) in development of water quality criteria were evaluated using polychlorinated biphenyls (PCB) data from the Hudson River and Green Bay ecosystems. Greater than 90% of th...

  9. 48 CFR 815.304 - Evaluation factors and significant subfactors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Evaluation factors and significant subfactors. 815.304 Section 815.304 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Source Selection 815.304...

  10. 48 CFR 315.304 - Evaluation factors and significant subfactors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 4 2011-10-01 2011-10-01 false Evaluation factors and significant subfactors. 315.304 Section 315.304 Federal Acquisition Regulations System HEALTH AND HUMAN SERVICES CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Source Selection 315.304...

  11. 48 CFR 15.304 - Evaluation factors and significant subfactors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Evaluation factors and significant subfactors. 15.304 Section 15.304 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Source Selection 15.304...

  12. Optimal design of disc-type magneto-rheological brake for mid-sized motorcycle: experimental evaluation

    NASA Astrophysics Data System (ADS)

    Sohn, Jung Woo; Jeon, Juncheol; Nguyen, Quoc Hung; Choi, Seung-Bok

    2015-08-01

    In this paper, a disc-type magneto-rheological (MR) brake is designed for a mid-sized motorcycle and its performance is experimentally evaluated. The proposed MR brake consists of an outer housing, a rotating disc immersed in MR fluid, and a copper wire coiled around a bobbin to generate a magnetic field. The structural configuration of the MR brake is first presented with consideration of the installation space for the conventional hydraulic brake of a mid-sized motorcycle. The design parameters of the proposed MR brake are optimized to satisfy design requirements such as the braking torque, total mass of the MR brake, and cruising temperature caused by the magnetic-field friction of the MR fluid. In the optimization procedure, the braking torque is calculated based on the Herschel-Bulkley rheological model, which predicts MR fluid behavior well at high shear rate. An optimization tool based on finite element analysis is used to obtain the optimized dimensions of the MR brake. After manufacturing the MR brake, mechanical performances regarding the response time, braking torque and cruising temperature are experimentally evaluated.

  13. Evaluating the ergonomics of BCI devices for research and experimentation.

    PubMed

    Ekandem, Joshua I; Davis, Timothy A; Alvarez, Ignacio; James, Melva T; Gilbert, Juan E

    2012-01-01

    The use of brain computer interface (BCI) devices in research and applications has exploded in recent years. Applications such as lie detectors that use functional magnetic resonance imaging (fMRI) to video games controlled using electroencephalography (EEG) are currently in use. These developments, coupled with the emergence of inexpensive commercial BCI headsets, such as the Emotiv EPOC ( http://emotiv.com/index.php ) and the Neurosky MindWave, have also highlighted the need of performing basic ergonomics research since such devices have usability issues, such as comfort during prolonged use, and reduced performance for individuals with common physical attributes, such as long or coarse hair. This paper examines the feasibility of using consumer BCIs in scientific research. In particular, we compare user comfort, experiment preparation time, signal reliability and ease of use in light of individual differences among subjects for two commercially available hardware devices, the Emotiv EPOC and the Neurosky MindWave. Based on these results, we suggest some basic considerations for selecting a commercial BCI for research and experimentation. STATEMENT OF RELEVANCE: Despite increased usage, few studies have examined the usability of commercial BCI hardware. This study assesses usability and experimentation factors of two commercial BCI models, for the purpose of creating basic guidelines for increased usability. Finding that more sensors can be less comfortable and accurate than devices with fewer sensors.

  14. Analysis of Thickness and Quality factor of a Double Paddle Oscillator at Room Temperature.

    PubMed

    Shakeel, Hamza; Metcalf, Thomas H; Pomeroy, J M

    2016-01-01

    In this paper, we evaluate the quality (Q) factor and the resonance frequency of a double paddle oscillator (DPO) with different thickness using analytical, computational and experimental methods. The study is carried out for the 2 nd anti-symmetric resonance mode that provides extremely high experimental Q factors on the order of 10 5 . The results show that both the Q factor and the resonance frequency of a DPO increase with the thickness at room temperature.

  15. Mitochondrial protection by low doses of insulin-like growth factor- I in experimental cirrhosis.

    PubMed

    Pérez, Raquel; García-Fernández, María; Díaz-Sánchez, Matías; Puche, Juan E; Delgado, Gloria; Conchillo, Marian; Muntané, Jordi; Castilla-Cortázar, Inma

    2008-05-07

    To characterize the mitochondrial dysfunction in experimental cirrhosis and to study whether insulin-like growth factor-I (IGF- I) therapy (4 wk) is able to induce beneficial effects on damaged mitochondria leading to cellular protection. Wistar rats were divided into three groups: Control group, untreated cirrhotic rats and cirrhotic rats treated with IGF- I treatment (2 microg/100 g bw/d). Mitochondrial function was analyzed by flow cytometry in isolated hepatic mitochondria, caspase 3 activation was assessed by Western blot and apoptosis by TUNEL in the three experimental groups. Untreated cirrhotic rats showed a mitochondrial dysfunction characterized by a significant reduction of mitochondrial membrane potential (in status 4 and 3); an increase of intramitochondrial reactive oxigen species (ROS) generation and a significant reduction of ATPase activity. IGF- I therapy normalized mitochondrial function by increasing the membrane potential and ATPase activity and reducing the intramitochondrial free radical production. Activity of the electron transport complexes I and III was increased in both cirrhotic groups. In addition, untreated cirrhotic rats showed an increase of caspase 3 activation and apoptosis. IGF- I therapy reduced the expression of the active peptide of caspase 3 and resulted in reduced apoptosis. These results show that IGF- I exerts a mitochondrial protection in experimental cirrhosis leading to reduced apoptosis and increased ATP production.

  16. The course of experimental staphylococcus infection in albino mice during action of certain factors of space flight

    NASA Technical Reports Server (NTRS)

    Prokhorov, V. Y.; Shilov, V. M.; Borman, E. A.

    1980-01-01

    A study was made of the effect of certain factors of space flight, acceleration and hypokinesia, on the course of experimental staphylococcus infection in mice. Combined action of hypokinesia and acceleration caused a marked depression of the phagocytic activity of leukocytes and formation of a considerable amount of alpha toxin.

  17. Effect of plasma-rich in platelet-derived growth factors on peri-implant bone healing: An experimental study in canines

    PubMed Central

    Birang, Reza; Torabi, Alireza; Shahabooei, Mohammad; Rismanchian, Mansour

    2012-01-01

    Background: Tissue engineering principles can be exploited to enhance alveolar and peri-implant bone reconstruction by applying such biological factors as platelet-derived growth factors. The objective of the present study is to investigate the effect of autologous plasma-rich in growth factors (on the healing of peri-implant bone in canine mandible). Materials and Methods: In this prospective experimental animal study, two healthy canines of the Iranian mix breed were selected. Three months after removing their premolar teeth on both sides of the mandible, 12 implants of the Osteo Implant Corporationsystem, 5 mm in diameter and 10 mm in length, were selected to be implanted. Plasma rich in growth factors (PRGF) were applied on six implants while the other six were used as plain implants without the plasma. The implants were installed in osteotomy sites on both sides of the mandible to be removed after 4 weeks with the surrounding bones using a trephine bur. Mesio-distal sections and implant blocks, 50 μ in diameter containing the peri-implant bone, were prepared By basic fuchin toluidine-bluefor histological and histomorphometric evaluation by optical microscope. The data were analyzed using Mann-Whitney Test (P<0.05). Results: The bone trabeculae and the type of bone generation in PRGF and control groups had no statistically significant differences (P=0.261, P=0.2) although the parameters showed higher measured values in the PRGF group. However, compared to the control, application of PRGF had significantly increased bone-to-implant contact (P=0.028) Conclusion: Based on the results, it may be concluded that application of PRGF on the surface of implant may enhance bone-to-implant contact. PMID:22363370

  18. Trends in animal experimentation.

    PubMed

    Monteiro, Rosangela; Brandau, Ricardo; Gomes, Walter J; Braile, Domingo M

    2009-01-01

    The search of the understanding of etiological factors, mechanisms and treatment of the diseases has been taking to the development of several animal models in the last decades. To discuss aspects related to animal models of experimentation, animal choice and current trends in this field in our country. In addition, this study evaluated the frequency of experimental articles in medical journals. Five Brazilian journals indexed by LILACS, SciELO, MEDLINE, and recently incorporate for Institute for Scientific Information Journal of Citation Reports were analyzed. All the papers published in those journals, between 2007 and 2008, that used animal models, were selected based on the abstracts. Of the total of 832 articles published in the period, 92 (11.1%) experimentation papers were selected. The number of experimental articles ranged from 5.2% to 17.9% of the global content of the journal. In the instructions to the authors, four (80%) journals presented explicit reference to the ethical principles in the conduction of studies with animals. The induced animal models represented 100% of the articles analyzed in this study. The rat was the most employed animal in the analyzed articles (78.3%). The present study can contribute, supplying subsidies for adoption of future editorials policies regarding the publication of animal research papers in Brazilian Journal of Cardiovascular Surgery.

  19. A critical evaluation of the experimental design of studies of mechanism based enzyme inhibition, with implications for in vitro-in vivo extrapolation.

    PubMed

    Ghanbari, F; Rowland-Yeo, K; Bloomer, J C; Clarke, S E; Lennard, M S; Tucker, G T; Rostami-Hodjegan, A

    2006-04-01

    The published literature on mechanism based inhibition (MBI) of CYPs was evaluated with respect to experimental design, methodology and data analysis. Significant variation was apparent in the dilution factor, ratio of preincubation to incubation times and probe substrate concentrations used, and there were some anomalies in the estimation of associated kinetic parameters (k(inact), K(I), r). The impact of the application of inaccurate values of k(inact) and K(I) when extrapolating to the extent of inhibition in vivo is likely to be greatest for those compounds of intermediate inhibitory potency, but this also depends on the fraction of the net clearance of substrate subject to MBI and the pre-systemic and systemic exposure to the inhibitor. For potent inhibitors, the experimental procedure is unlikely to have a material influence on the maximum inhibition. Nevertheless, the bias in the values of the kinetic parameters may influence the time for recovery of enzyme activity following re-synthesis of the enzyme. Careful attention to the design of in vitro experiments to obtain accurate kinetic parameters is necessary for a reliable prediction of different aspects of the in vivo consequences of MBI. The review calls for experimental studies to quantify the impact of study design in studies of MBI, with a view to better harmonisation of protocols.

  20. Experimental Evaluation of the Tools of the Mind Pre-K Curriculum. Technical Report. Working Paper

    ERIC Educational Resources Information Center

    Farran, Dale C.; Wilson, Sandra J.; Meador, Deanna; Norvell, Jennifer; Nesbitt, Kimberly

    2015-01-01

    The experimental evaluation of the "Tools of the Mind Pre-K Curriculum" described in this report was designed to examine the effectiveness of the "Tools of the Mind" ("Tools") curriculum for enhancing children's self-regulation skills and their academic preparation for kindergarten when compared to the usual…

  1. The Impact of Regression to the Mean on Economic Evaluation in Quasi-Experimental Pre-Post Studies: The Example of Total Knee Replacement Using Data from the Osteoarthritis Initiative.

    PubMed

    Schilling, Chris; Petrie, Dennis; Dowsey, Michelle M; Choong, Peter F; Clarke, Philip

    2017-12-01

    Many treatments are evaluated using quasi-experimental pre-post studies susceptible to regression to the mean (RTM). Ignoring RTM could bias the economic evaluation. We investigated this issue using the contemporary example of total knee replacement (TKR), a common treatment for end-stage osteoarthritis of the knee. Data (n = 4796) were obtained from the Osteoarthritis Initiative database, a longitudinal observational study of osteoarthritis. TKR patients (n = 184) were matched to non-TKR patients, using propensity score matching on the predicted hazard of TKR and exact matching on osteoarthritis severity and health-related quality of life (HrQoL). The economic evaluation using the matched control group was compared to the standard method of using the pre-surgery score as the control. Matched controls were identified for 56% of the primary TKRs. The matched control HrQoL trajectory showed evidence of RTM accounting for a third of the estimated QALY gains from surgery using the pre-surgery HrQoL as the control. Incorporating RTM into the economic evaluation significantly reduced the estimated cost effectiveness of TKR and increased the uncertainty. A generalized ICER bias correction factor was derived to account for RTM in cost-effectiveness analysis. RTM should be considered in economic evaluations based on quasi-experimental pre-post studies. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  2. Factors influencing the results of faculty evaluation in Isfahan University of Medical Sciences.

    PubMed

    Kamali, Farahnaz; Yamani, Nikoo; Changiz, Tahereh; Zoubin, Fatemeh

    2018-01-01

    This study aimed to explore factors influencing the results of faculty member evaluation from the viewpoints of faculty members affiliated with Isfahan University of Medical Sciences, Isfahan, Iran. This qualitative study was done using a conventional content analysis method. Participants were faculty members of Isfahan University of Medical Sciences who, considering maximum variation in sampling, were chosen with a purposive sampling method. Semi-structured interviews were held with 11 faculty members until data saturation was reached. The interviews were transcribed verbatim and analyzed with conventional content analysis method for theme development. Further, the MAXQDA software was used for data management. The data analysis led to the development of two main themes, namely, "characteristics of the educational system" and "characteristics of the faculty member evaluation system." The first main theme consists of three categories, i.e. "characteristics of influential people in evaluation," "features of the courses," and "background characteristics." The other theme has the following as its categories: "evaluation methods," "evaluation tools," "evaluation process," and "application of evaluation results." Each category will have its subcategories. Many factors affect the evaluation of faculty members that should be taken into account by educational policymakers for improving the quality of the educational process. In addition to the factors that directly influence the educational system, methodological problems in the evaluation system need special attention.

  3. Entropy factor for randomness quantification in neuronal data.

    PubMed

    Rajdl, K; Lansky, P; Kostal, L

    2017-11-01

    A novel measure of neural spike train randomness, an entropy factor, is proposed. It is based on the Shannon entropy of the number of spikes in a time window and can be seen as an analogy to the Fano factor. Theoretical properties of the new measure are studied for equilibrium renewal processes and further illustrated on gamma and inverse Gaussian probability distributions of interspike intervals. Finally, the entropy factor is evaluated from the experimental records of spontaneous activity in macaque primary visual cortex and compared to its theoretical behavior deduced for the renewal process models. Both theoretical and experimental results show substantial differences between the Fano and entropy factors. Rather paradoxically, an increase in the variability of spike count is often accompanied by an increase of its predictability, as evidenced by the entropy factor. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. Source term evaluation for accident transients in the experimental fusion facility ITER

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

    Virot, F.; Barrachin, M.; Cousin, F.

    2015-03-15

    We have studied the transport and chemical speciation of radio-toxic and toxic species for an event of water ingress in the vacuum vessel of experimental fusion facility ITER with the ASTEC code. In particular our evaluation takes into account an assessed thermodynamic data for the beryllium gaseous species. This study shows that deposited beryllium dusts of atomic Be and Be(OH){sub 2} are formed. It also shows that Be(OT){sub 2} could exist in some conditions in the drain tank. (authors)

  5. Experimental evaluation of the Battelle accelerated test design for the solar array at Mead, Nebraska

    NASA Technical Reports Server (NTRS)

    Frickland, P. O.; Repar, J.

    1982-01-01

    A previously developed test design for accelerated aging of photovoltaic modules was experimentally evaluated. The studies included a review of relevant field experience, environmental chamber cycling of full size modules, and electrical and physical evaluation of the effects of accelerated aging during and after the tests. The test results indicated that thermally induced fatigue of the interconnects was the primary mode of module failure as measured by normalized power output. No chemical change in the silicone encapsulant was detectable after 360 test cycles.

  6. Experimental design methods for bioengineering applications.

    PubMed

    Keskin Gündoğdu, Tuğba; Deniz, İrem; Çalışkan, Gülizar; Şahin, Erdem Sefa; Azbar, Nuri

    2016-01-01

    Experimental design is a form of process analysis in which certain factors are selected to obtain the desired responses of interest. It may also be used for the determination of the effects of various independent factors on a dependent factor. The bioengineering discipline includes many different areas of scientific interest, and each study area is affected and governed by many different factors. Briefly analyzing the important factors and selecting an experimental design for optimization are very effective tools for the design of any bioprocess under question. This review summarizes experimental design methods that can be used to investigate various factors relating to bioengineering processes. The experimental methods generally used in bioengineering are as follows: full factorial design, fractional factorial design, Plackett-Burman design, Taguchi design, Box-Behnken design and central composite design. These design methods are briefly introduced, and then the application of these design methods to study different bioengineering processes is analyzed.

  7. Factors affecting evaluation culture within a non-formal educational organization.

    PubMed

    Vengrin, Courtney; Westfall-Rudd, Donna; Archibald, Thomas; Rudd, Rick; Singh, Kusum

    2018-08-01

    While research has been done on many aspects of evaluation within a variety of contexts and organizations, there is a lack of research surrounding the culture of evaluation. This study set out to examine this evaluative culture in one of the world's largest non-formal educational organizations through the use of an online survey and quantitative methodology. A path model was developed to examine the factors affecting evaluation culture. Results show perception regarding evaluation, program area, college major, location, training in evaluation, degree level, and years of experience explained 28% of the variance within evaluation culture. Results also found that the culture of evaluation is greatly impacted by leadership. By taking a closer look at the evaluation culture of a large non-formal educational organization, much can be learned about how to better develop and support evaluative work in other similar organizations and programs. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Extracting the Evaluations of Stereotypes: Bi-factor Model of the Stereotype Content Structure

    PubMed Central

    Sayans-Jiménez, Pablo; Cuadrado, Isabel; Rojas, Antonio J.; Barrada, Juan R.

    2017-01-01

    Stereotype dimensions—competence, morality and sociability—are fundamental to studying the perception of other groups. These dimensions have shown moderate/high positive correlations with each other that do not reflect the theoretical expectations. The explanation for this (e.g., halo effect) undervalues the utility of the shared variance identified. In contrast, in this work we propose that this common variance could represent the global evaluation of the perceived group. Bi-factor models are proposed to improve the internal structure and to take advantage of the information representing the shared variance among dimensions. Bi-factor models were compared with first order models and other alternative models in three large samples (300–309 participants). The relationships among the global and specific bi-factor dimensions with a global evaluation dimension (measured through a semantic differential) were estimated. The results support the use of bi-factor models rather than first order models (and other alternative models). Bi-factor models also show a greater utility to directly and more easily explore the stereotype content including its evaluative content. PMID:29085313

  9. Monoclonal antibody against interferon gamma can prevent experimental cerebral malaria and its associated overproduction of tumor necrosis factor.

    PubMed Central

    Grau, G E; Heremans, H; Piguet, P F; Pointaire, P; Lambert, P H; Billiau, A; Vassalli, P

    1989-01-01

    Experimental cerebral malaria (ECM), a lethal hyperacute neurological syndrome associated with high blood levels of tumor necrosis factor, develops in genetically susceptible (CBA/Ca) mice 7 days after infection with Plasmodium berghei ANKA strain. Injections of neutralizing monoclonal antibody against recombinant murine interferon gamma, not later than 4 days after infection, markedly reduced the incidence of ECM and the elevation in serum levels of tumor necrosis factor. This treatment prevented the cerebral lesions (plugging of brain vessels by monocytes, lymphocytes, and parasitized erythrocytes). In contrast, the extent of macrophage infiltration in lymphoid organs (which is a characteristic feature of mice developing ECM), as well as the course of infection, remained unaffected by the antibody treatment. Protected mice died at a later time of severe anemia and overwhelming parasitemia, the usual outcome of P. berghei infection in mice that are not susceptible to ECM. The present data indicate that interferon gamma constitutes an important link in the cytokine network that leads to brain vessel inflammation in experimental malaria. It is proposed that interferon gamma released by activated CD4+ T cells acts by augmenting both production and action of tumor necrosis factor. PMID:2501793

  10. Experimental and Computational Evaluation of Flush-Mounted, S-Duct Inlets

    NASA Technical Reports Server (NTRS)

    Berrier, Bobby L.; Allan, Brian G.

    2004-01-01

    A new high Reynolds number test capability for boundary layer ingesting inlets has been developed for the NASA Langley Research Center 0.3-Meter Transonic Cryogenic Tunnel. Using this new capability. an experimental investigation of four S-duct inlet configurations was conducted. A computational study of one of the inlets was also conducted using a Navier-Stokes solver. The objectives of this investigation were to: 1) develop a new high Reynolds number inlet test capability for flush-mounted inlets; 2) provide a database for CFD tool validation; 3) evaluate the performance of S-duct inlets with large amounts of boundary layer ingestion; and 4) provide a baseline inlet for future inlet flow-control studies. Tests were conducted at Mach numbers from 0.25 to 0.83. Reynolds numbers (based on duct exit diameter) from 5.1 million to a full-scale value of 13.9 million, and inlet mass-flow ratios from 0.39 to 1.58 depending on Mach number. Results of the experimental study indicate that inlet pressure recovery generally decreased and inlet distortion generally increased with increasing Mach number. Except at low Mach numbers, increasing inlet mass-flow increased pressure recovery and increased distortion. Increasing the amount of boundary layer ingestion or ingesting a boundary layer with a distorted profile decreased pressure recovery and increased distortion. Finally, increasing Reynolds number had almost no effect on inlet distortion but increased inlet recovery by about one-half percent at a Mach number near cruise. The computational results captured the inlet pressure recovery and distortion trends with Mach number and inlet mass-flow well: the reversal of the pressure recovery trend with increasing inlet mass-flow at low and high Mach numbers was predicted by CFD. However, CFD results were generally more pessimistic (larger losses) than measured experimentally.

  11. Experimental evaluation of a mathematical model for predicting transfer efficiency of a high volume-low pressure air spray gun.

    PubMed

    Tan, Y M; Flynn, M R

    2000-10-01

    The transfer efficiency of a spray-painting gun is defined as the amount of coating applied to the workpiece divided by the amount sprayed. Characterizing this transfer process allows for accurate estimation of the overspray generation rate, which is important for determining a spray painter's exposure to airborne contaminants. This study presents an experimental evaluation of a mathematical model for predicting the transfer efficiency of a high volume-low pressure spray gun. The effects of gun-to-surface distance and nozzle pressure on the agreement between the transfer efficiency measurement and prediction were examined. Wind tunnel studies and non-volatile vacuum pump oil in place of commercial paint were used to determine transfer efficiency at nine gun-to-surface distances and four nozzle pressure levels. The mathematical model successfully predicts transfer efficiency within the uncertainty limits. The least squares regression between measured and predicted transfer efficiency has a slope of 0.83 and an intercept of 0.12 (R2 = 0.98). Two correction factors were determined to improve the mathematical model. At higher nozzle pressure settings, 6.5 psig and 5.5 psig, the correction factor is a function of both gun-to-surface distance and nozzle pressure level. At lower nozzle pressures, 4 psig and 2.75 psig, gun-to-surface distance slightly influences the correction factor, while nozzle pressure has no discernible effect.

  12. Air Traffic Control Experimentation and Evaluation with the NASA ATS-6 Satellite : Volume 1. Executive Summary

    DOT National Transportation Integrated Search

    1977-08-01

    The U.S. Department of Transportation (DOT), Federal Aviation Administration (FAA) program for air traffic control (ATC) experimentation and evaluation with the ATS-6 satellite was part of the Integrated ATS-6 L-Band Experiment. All tests were perfor...

  13. A Factor Analysis of the Counselor Evaluation Rating Scale

    ERIC Educational Resources Information Center

    Loesch, Larry C.; Rucker, Barbara B.

    1977-01-01

    This study was conducted on the Counselor Evaluation Rating Scale (CERS). Ratings on 404 students from approximately 35 different supervisors were factor-analyzed using an oblique solution with rotation to simple loadings. It was concluded that the CERS has generally achieved the purposes intended by its authors. (Author)

  14. An Evaluation of the Scattering Law for Light and Heavy Water in ENDF-6 Format, Based on Experimental Data and Molecular Dynamics

    NASA Astrophysics Data System (ADS)

    Márquez Damián, J. I.; Granada, J. R.; Malaspina, D. C.

    2014-04-01

    In this work we present an evaluation in ENDF-6 format of the scattering law for light and heavy water computed using the LEAPR module of NJOY99. The models used in this evaluation are based on experimental data on light water dynamics measured by Novikov, partial structure factors obtained by Soper, and molecular dynamics calculations performed with GROMACS using a reparameterized version of the flexible SPC model by Toukan and Rahman. The models use the Egelstaff-Schofield diffusion equation for translational motion, and a continuous spectrum calculated from the velocity autocorrelation function computed with GROMACS. The scattering law for H in H2O is computed using the incoherent approximation, and the scattering law D and O in D2O are computed using the Sköld approximation for coherent scattering. The calculations show significant improvement over ENDF/B-VI and ENDF/B-VII when compared with measurements of the total cross section, differential scattering experiments and quasi-elastic neutron scattering experiments (QENS).

  15. Meteorologic factors and subjective sleep continuity: a preliminary evaluation

    NASA Astrophysics Data System (ADS)

    Pandey, Juhi; Grandner, Michael; Crittenden, Crista; Smith, Michael T.; Perlis, Michael L.

    2005-01-01

    Little research has been undertaken to evaluate whether environmental factors other than bright light influence the individual’s ability to initiate and maintain sleep. In the present analyses, nine meteorologic variables were evaluated for their possible relationship to self-reported sleep continuity in a sample of 43 subjects over a period of 105 days. In this preliminary analysis, high barometric pressure, low precipitation, and lower temperatures were significantly correlated with good sleep continuity. Interestingly, ambient light and lunar phase were not found to be strongly associated sleep diary measures.

  16. Using experimental design to define boundary manikins.

    PubMed

    Bertilsson, Erik; Högberg, Dan; Hanson, Lars

    2012-01-01

    When evaluating human-machine interaction it is central to consider anthropometric diversity to ensure intended accommodation levels. A well-known method is the use of boundary cases where manikins with extreme but likely measurement combinations are derived by mathematical treatment of anthropometric data. The supposition by that method is that the use of these manikins will facilitate accommodation of the expected part of the total, less extreme, population. In literature sources there are differences in how many and in what way these manikins should be defined. A similar field to the boundary case method is the use of experimental design in where relationships between affecting factors of a process is studied by a systematic approach. This paper examines the possibilities to adopt methodology used in experimental design to define a group of manikins. Different experimental designs were adopted to be used together with a confidence region and its axes. The result from the study shows that it is possible to adapt the methodology of experimental design when creating groups of manikins. The size of these groups of manikins depends heavily on the number of key measurements but also on the type of chosen experimental design.

  17. Experimental and Molecular Modeling Evaluation of the Physicochemical Properties of Proline-Based Deep Eutectic Solvents.

    PubMed

    van den Bruinhorst, Adriaan; Spyriouni, Theodora; Hill, Jörg-Rüdiger; Kroon, Maaike C

    2018-01-11

    The liquid range and applicability of deep eutectic solvents (DESs) are determined by their physicochemical properties. In this work, the physicochemical properties of glycolic acid:proline and malic acid:proline were evaluated experimentally and with MD simulations at five different ratios. Both DESs exhibited esterification upon preparation, which affected the viscosity in particular. In order to minimize oligomer formation and water release, three different experimental preparation methods were explored, but none could prevent esterification. The experimental and calculated densities of the DESs were found to be in good agreement. The measured and modeled glass transition temperature showed similar trends with composition, as did the experimental viscosity and the calculated diffusivities. The MD simulations provided additional insight at the atomistic level, showing that at acid-rich compositions, the acid-acid hydrogen bonding (HB) interactions prevail. Malic acid-based DESs show stronger acid-acid HB interactions than glycolic acid-based ones, possibly explaining its extreme viscosity. Upon the addition of proline, the interspecies interactions become predominant, confirming the formation of the widely assumed HB network between the DESs constituents in the liquid phase.

  18. Factors influencing the results of faculty evaluation in Isfahan University of Medical Sciences

    PubMed Central

    Kamali, Farahnaz; Yamani, Nikoo; Changiz, Tahereh; Zoubin, Fatemeh

    2018-01-01

    OBJECTIVE: This study aimed to explore factors influencing the results of faculty member evaluation from the viewpoints of faculty members affiliated with Isfahan University of Medical Sciences, Isfahan, Iran. MATERIALS AND METHODS: This qualitative study was done using a conventional content analysis method. Participants were faculty members of Isfahan University of Medical Sciences who, considering maximum variation in sampling, were chosen with a purposive sampling method. Semi-structured interviews were held with 11 faculty members until data saturation was reached. The interviews were transcribed verbatim and analyzed with conventional content analysis method for theme development. Further, the MAXQDA software was used for data management. RESULTS: The data analysis led to the development of two main themes, namely, “characteristics of the educational system” and “characteristics of the faculty member evaluation system.” The first main theme consists of three categories, i.e. “characteristics of influential people in evaluation,” “features of the courses,” and “background characteristics.” The other theme has the following as its categories: “evaluation methods,” “evaluation tools,” “evaluation process,” and “application of evaluation results.” Each category will have its subcategories. CONCLUSIONS: Many factors affect the evaluation of faculty members that should be taken into account by educational policymakers for improving the quality of the educational process. In addition to the factors that directly influence the educational system, methodological problems in the evaluation system need special attention. PMID:29417073

  19. Probabilistic Multi-Factor Interaction Model for Complex Material Behavior

    NASA Technical Reports Server (NTRS)

    Abumeri, Galib H.; Chamis, Christos C.

    2010-01-01

    Complex material behavior is represented by a single equation of product form to account for interaction among the various factors. The factors are selected by the physics of the problem and the environment that the model is to represent. For example, different factors will be required for each to represent temperature, moisture, erosion, corrosion, etc. It is important that the equation represent the physics of the behavior in its entirety accurately. The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the external launch tanks. The multi-factor has sufficient degrees of freedom to evaluate a large number of factors that may contribute to the divot ejection. It also accommodates all interactions by its product form. Each factor has an exponent that satisfies only two points - the initial and final points. The exponent describes a monotonic path from the initial condition to the final. The exponent values are selected so that the described path makes sense in the absence of experimental data. In the present investigation, the data used were obtained by testing simulated specimens in launching conditions. Results show that the MFIM is an effective method of describing the divot weight ejected under the conditions investigated. The problem lies in how to represent the divot weight with a single equation. A unique solution to this problem is a multi-factor equation of product form. Each factor is of the following form (1 xi/xf)ei, where xi is the initial value, usually at ambient conditions, xf the final value, and ei the exponent that makes the curve represented unimodal that meets the initial and final values. The exponents are either evaluated by test data or by technical judgment. A minor disadvantage may be the selection of exponents in the absence of any empirical data. This form has been used successfully in describing the foam ejected in simulated space environmental conditions. Seven factors were required

  20. Development of Experimental and Computational Aeroacoustic Tools for Advanced Liner Evaluation

    NASA Technical Reports Server (NTRS)

    Jones, Michael G.; Watson, Willie R.; Nark, Douglas N.; Parrott, Tony L.; Gerhold, Carl H.; Brown, Martha C.

    2006-01-01

    Acoustic liners in aircraft engine nacelles suppress radiated noise. Therefore, as air travel increases, increasingly sophisticated tools are needed to maximize noise suppression. During the last 30 years, NASA has invested significant effort in development of experimental and computational acoustic liner evaluation tools. The Curved Duct Test Rig is a 152-mm by 381- mm curved duct that supports liner evaluation at Mach numbers up to 0.3 and source SPLs up to 140 dB, in the presence of user-selected modes. The Grazing Flow Impedance Tube is a 51- mm by 63-mm duct currently being fabricated to operate at Mach numbers up to 0.6 with source SPLs up to at least 140 dB, and will replace the existing 51-mm by 51-mm duct. Together, these test rigs allow evaluation of advanced acoustic liners over a range of conditions representative of those observed in aircraft engine nacelles. Data acquired with these test ducts are processed using three aeroacoustic propagation codes. Two are based on finite element solutions to convected Helmholtz and linearized Euler equations. The third is based on a parabolic approximation to the convected Helmholtz equation. The current status of these computational tools and their associated usage with the Langley test rigs is provided.

  1. Experimental design for the evaluation of struvite sedimentation obtained from an ammonium concentrated wastewater.

    PubMed

    Castro, Samuel Rodrigues; Araújo, Mahira Adna Cota; Lange, Liséte Celina

    2013-01-01

    Chemical precipitation of struvite as a technique of ammonium nitrogen (NH(4)-N) removal from concentrated wastewater has been shown to be an attractive alternative due to its high effectiveness, reaction rate, simplicity, environmental sustainability and, especially, the application potential of the generated solids for the fertilizer industry. The technique of experimental design has been used in order to identify and evaluate the optimum conditions of chemical precipitation reaction applied in a struvite sedimentation study. The preliminary tests were performed using synthetic effluent with a concentration equal to 500.0 mg N L(-1). The stoichiometric ratio Mg:NH(4):PO(4) equal to 1.5:1.0:1.25 and pH equal to 8.5 were taken to be the optimum conditions, where a NH(4)-N removal equal to 98.6% was achieved with only 10-min reaction time. This condition has been used to evaluate the struvite sedimentation from synthetic wastewaters, intending to check the optimum conditions achieved by the experimental design in different initial concentrations, 1,000 and 2,000 mg N L(-1). The results were typical of a good zonal sedimentation and can be used in the scale up the system.

  2. Dissemination Strategies to Improve Implementation of the PHS Smoking Cessation Guideline in MCH Public Health Clinics: Experimental Evaluation Results and Contextual Factors

    ERIC Educational Resources Information Center

    Manfredi, Clara; Cho, Young Ik; Warnecke, Richard; Saunders, Stephen; Sullivan, Myrtis

    2011-01-01

    We report results from an experimental study that tested the effectiveness of dissemination interventions to improve implementation of smoking cessation guidelines in maternal and child public health clinics. We additionally examine individual clinic results for contextual explanations not apparent from the experimental findings alone. Twelve…

  3. Long-term memory color investigation: culture effect and experimental setting factors.

    PubMed

    Zhu, Yuteng; Luo, Ming Ronnier; Fischer, Sebastian; Bodrogi, Peter; Khanh, Tran Quoc

    2017-10-01

    Memory colors generated continuous interest in the color community. Previous studies focused on reflecting color chips and color samples in real scenes or on monitors. The cognitive effect of culture was rarely considered. In this paper, we performed a comprehensive investigation of the long-term memory colors of 26 familiar objects using the asymmetric color matching method among Chinese and German observers on a display. Three experiments were conducted to evaluate the variations introduced by culture, context-based gray image, and initial matching color. Memory colors of important objects were collected and representative memory colors were quantified in terms of CIELAB L * , a * , and b * values. The intra- and inter-observer variations were analyzed by mean-color-difference-from-mean values and chromatic ellipses. The effects of different cultural groups and experimental settings were also shown.

  4. A meta-analysis of factors affecting trust in human-robot interaction.

    PubMed

    Hancock, Peter A; Billings, Deborah R; Schaefer, Kristin E; Chen, Jessie Y C; de Visser, Ewart J; Parasuraman, Raja

    2011-10-01

    We evaluate and quantify the effects of human, robot, and environmental factors on perceived trust in human-robot interaction (HRI). To date, reviews of trust in HRI have been qualitative or descriptive. Our quantitative review provides a fundamental empirical foundation to advance both theory and practice. Meta-analytic methods were applied to the available literature on trust and HRI. A total of 29 empirical studies were collected, of which 10 met the selection criteria for correlational analysis and 11 for experimental analysis. These studies provided 69 correlational and 47 experimental effect sizes. The overall correlational effect size for trust was r = +0.26,with an experimental effect size of d = +0.71. The effects of human, robot, and environmental characteristics were examined with an especial evaluation of the robot dimensions of performance and attribute-based factors. The robot performance and attributes were the largest contributors to the development of trust in HRI. Environmental factors played only a moderate role. Factors related to the robot itself, specifically, its performance, had the greatest current association with trust, and environmental factors were moderately associated. There was little evidence for effects of human-related factors. The findings provide quantitative estimates of human, robot, and environmental factors influencing HRI trust. Specifically, the current summary provides effect size estimates that are useful in establishing design and training guidelines with reference to robot-related factors of HRI trust. Furthermore, results indicate that improper trust calibration may be mitigated by the manipulation of robot design. However, many future research needs are identified.

  5. Evaluation of the Big Two-Factor Theory of Academic Motivation Orientations: An Evaluation of the Jingle-Jangle Fallacies.

    ERIC Educational Resources Information Center

    Marsh, Herbert W.; Craven, Rhonda G.; Hinkley, John W.; Debus, Raymond L.

    2003-01-01

    Collected test-retest data from 606 students in grades 3 through 6 in Australia to evaluate a Big Two-Factor Theory of academic motivation orientation. Findings provide reasonable support for the Big Two-Factor theory but suggest it is still useful to collect data from different motivation scales. (SLD)

  6. A Method to Evaluate Critical Factors for Successful Implementation of Clinical Pathways.

    PubMed

    Dong, W; Huang, Z

    2015-01-01

    Clinical pathways (CPs) have been viewed as a multidisciplinary tool to improve the quality and efficiency of evidence-based care. Despite widespread enthusiasm for CPs, research has shown that many CP initiatives are unsuccessful. To this end, this study provides a methodology to evaluate critical success factors (CSFs) that can aid healthcare organizations to achieve successful CP implementation. This study presents a new approach to evaluate CP implementation CSFs, with the aims being: (1) to identify CSFs for implementation of CPs through a comprehensive literature review and interviews with collaborative experts; (2) to use a filed study data with a robust fuzzy DEMATEL (the decision making trial and evaluation laboratory) approach to visualize the structure of complicated causal relationships between CSFs and obtain the influence level of these factors. The filed study data is provided by ten clinical experts of a Chinese hospital. 23 identified CSF factors which are initially identified through a review of the literature and interviews with collaborative experts. Then, a number of direct and indirect relationships are derived from the data such that different perceptions can be integrated into a compromised cause and effect model of CP implementation. The results indicate that the proposed approach can systematically evaluate CSFs and realize the importance of each factor such that the most common causes of failure of CP implementation could be eliminated or avoided. Therefore, the tool proposed would help healthcare organizations to manage CP implementation in a more effective and proactive way.

  7. Minnesota urban partnership agreement national evaluation : exogenous factors test plan.

    DOT National Transportation Integrated Search

    2009-11-17

    This report presents the exogenous factors test plan for the national evaluation of the Minnesota Urban Partnership Agreement (UPA) under the United States Department of Transportation (U.S. DOT) UPA Program. The Minnesota UPA projects focus on reduc...

  8. Evaluation of interleukin-1α, interleukin-10, tumor necrosis factor-α and transforming growth factor-β in the serum of patients with pemphigus vulgaris.

    PubMed

    Khozeimeh, Faezeh; Savabi, Omid; Esnaashari, Masih

    2014-11-01

    Pemphigus is an autoimmune blistering disease characterized by a loss of cell adhesion result in acantholysis. Genetic factors and immunologic factors such as cytokines particularly IL-1α, IL-10, TNF-α, and TGF-β may counterpart to developing of Pemphigus. The aim of this study was to evaluate. The concentration of IL-1α, IL-10, TNF-α, TGF-β in serum of pemphigus vulgaris (PV) patients and normal individuals. In this analytic and descriptive study 25 patients with pemphigus vulgaris (in active phase) and 25 healthy per sons were examined. Serum samples of two groups were obtained and the level of IL-1α, IL-10, TNF-α and TGF-β were measured by ELISA technique. The data were analyzed statistically by independent T test (α = 0/05). All cytokines tested, showed higher concentration in patient's sera comparing to healthy control individuals. The level of IL-1α (p = 0.004), TNF-α (p = 0.008) and TGF-β (p = 0.009) were statistically different in two experimental groups, There was no significant difference in IL-10 level (p = 0.605). Cytokines such as IL-1α, IL-10, TNF-α and TGF-β probably have a role in pathogenesis of PV. Further comprehensive studies are suggested to confirm these findings.

  9. Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a

    NASA Astrophysics Data System (ADS)

    Nasution, Henry; Zainudin, Muhammad Amir; Aziz, Azhar Abdul; Latiff, Zulkarnain Abdul; Perang, Mohd Rozi Mohd; Rahman, Abd Halim Abdul

    2012-06-01

    An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study, these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower, evaporator, condenser, radiators, electric motor, which acts as a vehicle engine, and then the electric motor will operate the compressor using a belt and pulley system, as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000, 1500, 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20°C with internal heat loads 0, 500, 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

  10. Experimentally evaluating the origin of dilute magnetism in nanomaterials

    NASA Astrophysics Data System (ADS)

    Pereira, L. M. C.

    2017-10-01

    Reports of room-temperature ferromagnetism continue to emerge for an ever-growing range of nanomaterials with a small or even vanishing concentration of magnetic atoms. Dilute magnetic semiconductors (DMS) are the most representative class of such materials, but similar magnetic properties have been reported in many others. Challenging our understanding of magnetic order in solids, as well as our ability to experimentally assess it, these remarkable magnetic phenomena have become one of the most controversial topics in magnetism. Various non-intrinsic sources of ferromagnetism (e.g. instrumental artifacts and magnetic contamination) are becoming well documented, and rarely are all of them taken into account when room-temperature ferromagnetism is reported. This topical review is intended to serve as a guide when evaluating to what extent a given data set supports the claim of intrinsic ferromagnetism in dilute nanomaterials. It compiles the most relevant sources of non-intrinsic ferromagnetism which have been reported, as well as guidelines for how to minimize them. It also provides an overview of complementary structural and magnetic characterization techniques which can be combined to provide different levels of scrutiny of the intrinsic nature of experimentally observed ferromagnetism. In particular, it gives some notable examples of how comprehensive studies based on those techniques have led to a remarkably detailed understanding of model DMS materials, with strong evidence of absence of room-temperature ferromagnetism. Although mostly based on DMS research, this review provides a set of guidelines and cautionary notes of broader relevance, including some emerging new fields of dilute nanomagnetism such as magnetically doped 3D topological insulators, 3D Dirac semimetals, and 2D materials.

  11. Experimental study of evaluation of mechanical parameters of heterogeneous porous structure

    NASA Astrophysics Data System (ADS)

    Gerasimov, O.; Koroleva, E.; Sachenkov, O.

    2017-06-01

    The paper deals with the problem of determining the mechanical macroparameters of the porous material in case of knowing the information about it’s structure. Fabric tensor and porosity was used to describe structure of the material. Experimental study presented. In research two-component liquid polyurethane plastics of cold curing Lasilcast (Lc-12) was used. Then samples was scanned on computer tomography. Resulting data was analyzed. Regular subvolume was cut out after analyses. Then mechanical tests was performed. As a result we get information about fabric tensor, porosity, Young’s modulus and Poisson ratio of the sample. In the abstract presented results for some samples. Taking into account the law of porosity variation, we considered the problem of evaluating the mechanical macro parameters depending on the nature of the porous structure. To evaluate the macroparameters, we built the dependence of the Young’s modules and Poisson ratio of the material on the rotation angle α and the pore ellipticity parameter λ. The sensitivity of the deformations to the elastic constants was also estimated.

  12. Preliminary evaluation of factors associated with premature trial closure and feasibility of accrual benchmarks in phase III oncology trials.

    PubMed

    Schroen, Anneke T; Petroni, Gina R; Wang, Hongkun; Gray, Robert; Wang, Xiaofei F; Cronin, Walter; Sargent, Daniel J; Benedetti, Jacqueline; Wickerham, Donald L; Djulbegovic, Benjamin; Slingluff, Craig L

    2010-08-01

    A major challenge for randomized phase III oncology trials is the frequent low rates of patient enrollment, resulting in high rates of premature closure due to insufficient accrual. We conducted a pilot study to determine the extent of trial closure due to poor accrual, feasibility of identifying trial factors associated with sufficient accrual, impact of redesign strategies on trial accrual, and accrual benchmarks designating high failure risk in the clinical trials cooperative group (CTCG) setting. A subset of phase III trials opened by five CTCGs between August 1991 and March 2004 was evaluated. Design elements, experimental agents, redesign strategies, and pretrial accrual assessment supporting accrual predictions were abstracted from CTCG documents. Percent actual/predicted accrual rate averaged per month was calculated. Trials were categorized as having sufficient or insufficient accrual based on reason for trial termination. Analyses included univariate and bivariate summaries to identify potential trial factors associated with accrual sufficiency. Among 40 trials from one CTCG, 21 (52.5%) trials closed due to insufficient accrual. In 82 trials from five CTCGs, therapeutic trials accrued sufficiently more often than nontherapeutic trials (59% vs 27%, p = 0.05). Trials including pretrial accrual assessment more often achieved sufficient accrual than those without (67% vs 47%, p = 0.08). Fewer exclusion criteria, shorter consent forms, other CTCG participation, and trial design simplicity were not associated with achieving sufficient accrual. Trials accruing at a rate much lower than predicted (<35% actual/predicted accrual rate) were consistently closed due to insufficient accrual. This trial subset under-represents certain experimental modalities. Data sources do not allow accounting for all factors potentially related to accrual success. Trial closure due to insufficient accrual is common. Certain trial design factors appear associated with attaining

  13. Preliminary evaluation of factors associated with premature trial closure and feasibility of accrual benchmarks in phase III oncology trials

    PubMed Central

    Schroen, Anneke T; Petroni, Gina R; Wang, Hongkun; Gray, Robert; Wang, Xiaofei F; Cronin, Walter; Sargent, Daniel J; Benedetti, Jacqueline; Wickerham, Donald L; Djulbegovic, Benjamin; Slingluff, Craig L

    2014-01-01

    Background A major challenge for randomized phase III oncology trials is the frequent low rates of patient enrollment, resulting in high rates of premature closure due to insufficient accrual. Purpose We conducted a pilot study to determine the extent of trial closure due to poor accrual, feasibility of identifying trial factors associated with sufficient accrual, impact of redesign strategies on trial accrual, and accrual benchmarks designating high failure risk in the clinical trials cooperative group (CTCG) setting. Methods A subset of phase III trials opened by five CTCGs between August 1991 and March 2004 was evaluated. Design elements, experimental agents, redesign strategies, and pretrial accrual assessment supporting accrual predictions were abstracted from CTCG documents. Percent actual/predicted accrual rate averaged per month was calculated. Trials were categorized as having sufficient or insufficient accrual based on reason for trial termination. Analyses included univariate and bivariate summaries to identify potential trial factors associated with accrual sufficiency. Results Among 40 trials from one CTCG, 21 (52.5%) trials closed due to insufficient accrual. In 82 trials from five CTCGs, therapeutic trials accrued sufficiently more often than nontherapeutic trials (59% vs 27%, p = 0.05). Trials including pretrial accrual assessment more often achieved sufficient accrual than those without (67% vs 47%, p = 0.08). Fewer exclusion criteria, shorter consent forms, other CTCG participation, and trial design simplicity were not associated with achieving sufficient accrual. Trials accruing at a rate much lower than predicted (<35% actual/predicted accrual rate) were consistently closed due to insufficient accrual. Limitations This trial subset under-represents certain experimental modalities. Data sources do not allow accounting for all factors potentially related to accrual success. Conclusion Trial closure due to insufficient accrual is common. Certain

  14. Free bone graft reconstruction of irradiated facial tissue: Experimental effects of basic fibroblast growth factor stimulation

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

    Eppley, B.L.; Connolly, D.T.; Winkelmann, T.

    1991-07-01

    A study was undertaken to evaluate the potential utility of basic fibroblast growth factor in the induction of angiogenesis and osseous healing in bone previously exposed to high doses of irradiation. Thirty New Zealand rabbits were evaluated by introducing basic fibroblast growth factor into irradiated mandibular resection sites either prior to or simultaneous with reconstruction by corticocancellous autografts harvested from the ilium. The fate of the free bone grafts was then evaluated at 90 days postoperatively by microangiographic, histologic, and fluorochrome bone-labeling techniques. Sequestration, necrosis, and failure to heal to recipient osseous margins was observed both clinically and histologically inmore » all nontreated irradiated graft sites as well as those receiving simultaneous angiogenic stimulation at the time of graft placement. No fluorescent activity was seen in these graft groups. In the recipient sites pretreated with basic fibroblast growth factor prior to placement of the graft, healing and reestablishment of mandibular contour occurred in nearly 50 percent of the animals. Active bone formation was evident at cortical margins adjacent to the recipient sites but was absent in the more central cancellous regions of the grafts.« less

  15. Ecto-5'-nucleotidase: a candidate virulence factor in Streptococcus sanguinis experimental endocarditis.

    PubMed

    Fan, Jingyuan; Zhang, Yongshu; Chuang-Smith, Olivia N; Frank, Kristi L; Guenther, Brian D; Kern, Marissa; Schlievert, Patrick M; Herzberg, Mark C

    2012-01-01

    Streptococcus sanguinis is the most common cause of infective endocarditis (IE). Since the molecular basis of virulence of this oral commensal bacterium remains unclear, we searched the genome of S. sanguinis for previously unidentified virulence factors. We identified a cell surface ecto-5'-nucleotidase (Nt5e), as a candidate virulence factor. By colorimetric phosphate assay, we showed that S. sanguinis Nt5e can hydrolyze extracellular adenosine triphosphate to generate adenosine. Moreover, a nt5e deletion mutant showed significantly shorter lag time (P<0.05) to onset of platelet aggregation than the wild-type strain, without affecting platelet-bacterial adhesion in vitro (P=0.98). In the absence of nt5e, S. sanguinis caused IE (4 d) in a rabbit model with significantly decreased mass of vegetations (P<0.01) and recovered bacterial loads (log(10)CFU, P=0.01), suggesting that Nt5e contributes to the virulence of S. sanguinis in vivo. As a virulence factor, Nt5e may function by (i) hydrolyzing ATP, a pro-inflammatory molecule, and generating adenosine, an immunosuppressive molecule to inhibit phagocytic monocytes/macrophages associated with valvular vegetations. (ii) Nt5e-mediated inhibition of platelet aggregation could also delay presentation of platelet microbicidal proteins to infecting bacteria on heart valves. Both plausible Nt5e-dependent mechanisms would promote survival of infecting S. sanguinis. In conclusion, we now show for the first time that streptococcal Nt5e modulates S. sanguinis-induced platelet aggregation and may contribute to the virulence of streptococci in experimental IE.

  16. Some human factors issues in the development and evaluation of cockpit alerting and warning systems

    NASA Technical Reports Server (NTRS)

    Randle, R. J., Jr.; Larsen, W. E.; Williams, D. H.

    1980-01-01

    A set of general guidelines for evaluating a newly developed cockpit alerting and warning system in terms of human factors issues are provided. Although the discussion centers around a general methodology, it is made specifically to the issues involved in alerting systems. An overall statement of the current operational problem is presented. Human factors problems with reference to existing alerting and warning systems are described. The methodology for proceeding through system development to system test is discussed. The differences between traditional human factors laboratory evaluations and those required for evaluation of complex man-machine systems under development are emphasized. Performance evaluation in the alerting and warning subsystem using a hypothetical sample system is explained.

  17. Evaluation of procoagulant tissue factor expression in canine hemangiosarcoma cell lines.

    PubMed

    Witter, Lauren E; Gruber, Erika J; Lean, Fabian Z X; Stokol, Tracy

    2017-01-01

    OBJECTIVE To evaluate expression of procoagulant tissue factor (TF) by canine hemangiosarcoma cells in vitro. SAMPLES 4 canine hemangiosarcoma cell lines (SB-HSA [mouse-passaged cutaneous tumor], Emma [primary metastatic brain tumor], and Frog and Dal-1 [primary splenic tumors]) and 1 nonneoplastic canine endothelial cell line (CnAoEC). PROCEDURES TF mRNA and TF antigen expression were evaluated by quantitative real-time PCR assay and flow cytometry, respectively. Thrombin generation was measured in canine plasma and in coagulation factor-replete or specific coagulation factor-deficient human plasma by calibrated automated thrombography. Corn trypsin inhibitor and annexin V were used to examine contributions of contact activation and membrane-bound phosphatidylserine, respectively, to thrombin generation. RESULTS All cell lines expressed TF mRNA and antigen, with significantly greater expression of both products in SB-HSA and Emma cells than in CnAoEC. A greater percentage of SB-HSA cells expressed TF antigen, compared with other hemangiosarcoma cell lines. All hemangiosarcoma cell lines generated significantly more thrombin than did CnAoEC in canine or factor-replete human plasma. Thrombin generation induced by SB-HSA cells was significantly lower in factor VII-deficient plasma than in factor-replete plasma and was abolished in factor X-deficient plasma; residual thrombin generation in factor VII-deficient plasma was abolished by incubation of cells with annexin V. Thrombin generation by SB-HSA cells was unaffected by the addition of corn trypsin inhibitor. CONCLUSIONS AND CLINICAL RELEVANCE Hemangiosarcoma cell lines expressed procoagulant TF in vitro. Further research is needed to determine whether TF can be used as a biomarker for hemostatic dysfunction in dogs with hemangiosarcoma.

  18. Scientific Reasoning in Early and Middle Childhood: The Development of Domain-General Evidence Evaluation, Experimentation, and Hypothesis Generation Skills

    ERIC Educational Resources Information Center

    Piekny, Jeanette; Maehler, Claudia

    2013-01-01

    According to Klahr's (2000, 2005; Klahr & Dunbar, 1988) Scientific Discovery as Dual Search model, inquiry processes require three cognitive components: hypothesis generation, experimentation, and evidence evaluation. The aim of the present study was to investigate (a) when the ability to evaluate perfect covariation, imperfect covariation,…

  19. Experimental evaluation of multiscale tendon mechanics.

    PubMed

    Fang, Fei; Lake, Spencer P

    2017-07-01

    Tendon's primary function is a mechanical link between muscle and bone. The hierarchical structure of tendon and specific compositional constituents are believed to be critical for proper mechanical function. With increased appreciation for tendon importance and the development of various technological advances, this review paper summarizes recent experimental approaches that have been used to study multiscale tendon mechanics, includes an overview of studies that have evaluated the role of specific tissue constituents, and also proposes challenges/opportunities facing tendon study. Tendon has been demonstrated to have specific structural characteristics (e.g., multi-level hierarchy, crimp pattern, helix) and complex mechanical properties (e.g., non-linearity, anisotropy, viscoelasticity). Physical mechanisms including uncrimping, fiber sliding, and collagen reorganization have been shown to govern tendon mechanical responses under both static and dynamic loading. Several tendon constituents with relatively small quantities have been suggested to play a role in its mechanics, although some results are conflicting. Further research should be performed to understand the interplay and communication of tendon mechanical properties across levels of the hierarchical structure, and further show how each of these components contribute to tendon mechanics. The studies summarized and discussed in this review have helped elucidate important aspects of multiscale tendon mechanics, which is a prerequisite for analyzing stress/strain transfer between multiple scales and identifying key principles of mechanotransduction. This information could further facilitate interpreting the functional diversity of tendons from different species, different locations, and even different developmental stages, and then better understand and identify fundamental concepts related to tendon degeneration, disease, and healing. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc

  20. Evaluating the effects of pentoxifylline administration on experimental pressure sores in rats by biomechanical examinations

    PubMed Central

    Velaei, Kobra; Torkman, Giti; Rezaie, Fatemealsadat; Amini, Abdollah; Noruzian, Mohsen; Tavassol, Azaedh; Bayat, Mehernoush

    2012-01-01

    This study used a biomechanical test to evaluate the effects of pentoxifylline administration on the wound healing process of an experimental pressure sore induced in rats. Under general anesthesia and sterile conditions, experimental pressure sores generated by no. 25 Halsted mosquito forceps were inflicted on 12 adult male rats. Pentoxifylline was injected intraperitoneally at a dose of 50 mg/kg daily from the day the pressure sore was generated, for a period of 20 days. At the end of 20 days, rats were sacrificed and skin samples extracted. Samples were biomechanically examined by a material testing instrument for maximum stress (N mm2), work up to maximum force (N), and elastic stiffness (N/mm). In the experimental group, maximum stress (2.05±0.15) and work up to maximum force (N/mm) (63.75±4.97) were significantly higher than the control group (1.3±0.27 and 43.3±14.96, P=0.002 and P=0.035, respectively). Pentoxifylline administration significantly accelerated the wound healing process in experimental rats with pressure sores, compared to that of the control group. PMID:23091522

  1. Evaluating the effects of pentoxifylline administration on experimental pressure sores in rats by biomechanical examinations.

    PubMed

    Velaei, Kobra; Bayat, Mohammad; Torkman, Giti; Rezaie, Fatemealsadat; Amini, Abdollah; Noruzian, Mohsen; Tavassol, Azaedh; Bayat, Mehernoush

    2012-09-01

    This study used a biomechanical test to evaluate the effects of pentoxifylline administration on the wound healing process of an experimental pressure sore induced in rats. Under general anesthesia and sterile conditions, experimental pressure sores generated by no. 25 Halsted mosquito forceps were inflicted on 12 adult male rats. Pentoxifylline was injected intraperitoneally at a dose of 50 mg/kg daily from the day the pressure sore was generated, for a period of 20 days. At the end of 20 days, rats were sacrificed and skin samples extracted. Samples were biomechanically examined by a material testing instrument for maximum stress (N mm(2)), work up to maximum force (N), and elastic stiffness (N/mm). In the experimental group, maximum stress (2.05±0.15) and work up to maximum force (N/mm) (63.75±4.97) were significantly higher than the control group (1.3±0.27 and 43.3±14.96, P=0.002 and P=0.035, respectively). Pentoxifylline administration significantly accelerated the wound healing process in experimental rats with pressure sores, compared to that of the control group.

  2. Harnessing Information Technology to Improve the Process of Students' Evaluations of Teaching: An Exploration of Students' Critical Success Factors of Online Evaluations

    ERIC Educational Resources Information Center

    Nevo, Dorit; McClean, Ron; Nevo, Saggi

    2010-01-01

    This paper discusses the relative advantage offered by online Students' Evaluations of Teaching (SET) and describes a study conducted at a Canadian university to identify critical success factors of online evaluations from students' point of view. Factors identified as important by the students include anonymity, ease of use (of both SET survey…

  3. A comparative and experimental evaluation of performance of stocked diploid and triploid brook trout

    USGS Publications Warehouse

    Budy, Phaedra E.; Thiede, G.P.; Dean, A.; Olsen, D.; Rowley, G.

    2012-01-01

    Despite numerous negative impacts, nonnative trout are still being stocked to provide economically and socially valuable sport fisheries in western mountain lakes. We evaluated relative performance and potential differences in feeding strategy and competitive ability of triploid versus diploid brook trout Salvelinus fontinalis in alpine lakes, as well as behavioral and performance differences of diploid and triploid brook trout in two controlled experimental settings: behavioral experiments in the laboratory and performance evaluations in ponds. Across lakes, catch per unit effort (CPUE) and relative weight (Wr ) were not significantly different between ploidy levels. Mean sizes were also similar between ploidy levels except in two of the larger lakes where diploids attained slightly larger sizes (approximately 20 mm longer). We observed no significant differences between diploids and triploids in diet, diet preference, or trophic structure. Similarly, growth and condition did not differ between ploidy levels in smaller-scale pond experiments, and aggressive behavior did not differ between ploidy levels (fed or unfed fish trials) in the laboratory. Independent of ploidy level, the relative performance of brook trout varied widely among lakes, a pattern that appeared to be a function of lake size or a factor that covaries with lake size such as temperature regime or carrying capacity. In summary, we observed no significant differences in the relative performance of brook trout from either ploidy level across a number of indices, systems, and environmental conditions, nor any indication that one group is more aggressive or a superior competitor than the other. Collectively, these results suggest that triploid brook trout will offer a more risk-averse and promising management opportunity when they are stocked to these lakes and elsewhere to simultaneously meet the needs for the sport fishery and conservation objectives.

  4. Analytical and experimental evaluation of a 3-D hypersonic fixed-geometry, swept, mixed compression inlet

    NASA Technical Reports Server (NTRS)

    Agnone, Anthony M.

    1987-01-01

    The performance of a fixed-geometry, swept, mixed compression hypersonic inlet is presented. The experimental evaluation was conducted for a Mach number of 6.0 and for several angles of attack. The measured surface pressures and pitot pressure surveys at the inlet throat are compared to computations using a three-dimensional Euler code and an integral boundary layer theory. Unique features of the intake design, including the boundary layer control, insure a high inlet performance. The experimental data show the inlet has a high mass averaged total pressure recovery, a high mass capture and nearly uniform flow diffusion. The swept inlet exhibits excellent starting characteristics, and high flow stability at angle of attack.

  5. An evaluation of evaluative personality terms: a comparison of the big seven and five-factor model in predicting psychopathology.

    PubMed

    Durrett, Christine; Trull, Timothy J

    2005-09-01

    Two personality models are compared regarding their relationship with personality disorder (PD) symptom counts and with lifetime Axis I diagnoses. These models share 5 similar domains, and the Big 7 model also includes 2 domains assessing self-evaluation: positive and negative valence. The Big 7 model accounted for more variance in PDs than the 5-factor model, primarily because of the association of negative valence with most PDs. Although low-positive valence was associated with most Axis I diagnoses, the 5-factor model generally accounted for more variance in Axis I diagnoses than the Big 7 model. Some predicted associations between self-evaluation and psychopathology were not found, and unanticipated associations emerged. These findings are discussed regarding the utility of evaluative terms in clinical assessment.

  6. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 4A : design specifications.

    DOT National Transportation Integrated Search

    2015-08-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 4A, Design Specifications. : Structural design specifications are base...

  7. Evaluation of in-vehicle HMI using occlusion techniques: experimental results and practical implications.

    PubMed

    Baumann, Martin; Keinath, Andreas; Krems, Josef F; Bengler, Klaus

    2004-05-01

    Despite the usefulness of new on-board information systems one has to be concerned about the potential distraction effects that they impose on the driver. Therefore, methods and procedures are necessary to assess the visual demand that is connected to the usage of an on-board system. The occlusion-method is considered a strong candidate as a procedure for evaluating display designs with regard to their visual demand. This paper reports results from two experimental studies conducted to further evaluate this method. In the first study, performance in using an in-car navigation system was measured under three conditions: static (parking lot), occlusion (shutter glasses), and driving. The results show that the occlusion-procedure can be used to simulate visual requirements of real traffic conditions. In a second study the occlusion method was compared to a global evaluation criterion based on the total task time. It can be demonstrated that the occlusion method can identify tasks which meet this criterion, but are yet irresolvable under driving conditions. It is concluded that the occlusion technique seems to be a reliable and valid method for evaluating visual and dialogue aspects of in-car information systems.

  8. [Environmental factors and male fertility].

    PubMed

    Köhn, F-M; Schuppe, H C

    2016-07-01

    The identification of potential environmental hazards may have clinical relevance for diagnosis of male infertility. Knowledge about these factors will improve prevention of fertility disorders. Apart from drugs or factors related to lifestyle such as alcohol and tobacco smoke, various environmental and occupational agents, both chemical and physical, may impair male reproductive functions. With regard to the complex regulation of the male reproductive system, the available information concerning single exogenous factors and their mechanisms of action in humans is limited. This is also due to the fact that extrapolation of results obtained from experimental animal studies remains difficult. Nevertheless, the assessment of relevant exposures to reproductive toxicants should be carefully evaluated during diagnostic procedures of andrological patients.

  9. Association between social factors and performance during Functional Capacity Evaluations: a systematic review.

    PubMed

    Ansuategui Echeita, Jone; van Holland, Berry J; Gross, Douglas P; Kool, Jan; Oesch, Peter; Trippolini, Maurizio A; Reneman, Michiel F

    2018-03-09

    Determine the association of different social factors with Functional Capacity Evaluation (FCE) performance in adults. A systematic literature search was performed in MEDLINE, CINAHL, and PsycINFO electronic databases. Studies were eligible if they studied social factor's association with the performance of adults undergoing FCE. Studies were assessed on methodological quality and quality of evidence. The review was performed using best-evidence synthesis methods. Thirteen studies were eligible and 11 social factors were studied. Considerable heterogeneity regarding measurements, populations, and methods existed among the studies. High quality of evidence was found for the association of FCE performance with the country of FCE and examiner's fear behavior; moderate quality of evidence with previous job salary; and low or very low quality of evidence with compensation status, litigation status, type of instruction, time of day (workday), primary or mother language, and ethnicity. Other social factors were not studied. Evidence for associations of various social factors with FCE performance was found, but robust conclusions about the strength of the associations cannot be made. Quality of evidence ranged from high to very low. Further research on social factors, also within a biopsychosocial context, is necessary to provide a better understanding of FCE performance. Implications for Rehabilitation Research on Functional Capacity Evaluation (FCE) performance and its association with biopsychosocial factors have scarcely addressed the impact of social factors, limiting full understanding of FCE results. The social factors, healthcare (examiner's fear behavior and type of instruction), personal or cultural systems (country of FCE, primary or mother language, and ethnicity), workplace system (previous job salary, time of day (workday)), and legislative and insurance system (compensation and litigation status), have a bearing in FCE performance. Better understanding of

  10. Formative Evaluation of an Experimental BE/E [Basic Electricity and Electronics] Program. Report No. 9-75.

    ERIC Educational Resources Information Center

    Fishburne, R. P., Jr.; Mims, Diane M.

    An experimental Basic Electricity and Electronics course (BE/E) utilizing a lock-step, instructor presentation methodology was developed and evaluated at the Service School Command, Great Lakes. The study, directed toward the training of lower mental group, school nonqualified personnel, investigated comparative data on test performance, attitude,…

  11. Comparative Evaluation of Two Vaccine Candidates against Experimental Leishmaniasis Due to Leishmania major Infection in Four Inbred Mouse Strains▿

    PubMed Central

    Benhnini, Fouad; Chenik, Mehdi; Laouini, Dhafer; Louzir, Hechmi; Cazenave, Pierre André; Dellagi, Koussay

    2009-01-01

    Experimental leishmaniasis in BALB/c and C57BL/6 mice are the most investigated murine models that were used for the preclinical evaluation of Leishmania vaccine candidates. We have previously described two new inbred mouse strains named PWK and MAI issued from feral founders that also support the development of experimental leishmaniasis due to L. major. In this study, we sought to determine whether different mouse inbred strains generate concordant or discordant results when used to evaluate the potential of Leishmania proteins to protect against experimental leishmaniasis. To this end, two Leishmania proteins, namely, LACK (for Leishmania homolog of receptor for activated C kinase) and LmPDI (for L. major protein disulfide isomerase) were compared for their capacity to protect against experimental leishmaniasis in PWK, MAI, BALB/c, and C57BL/6 inbred mouse strains. Our data show that the capacity of Leishmania proteins to confer protection depends on the mouse strain used, stressing the important role played by the genetic background in shaping the immune response against the pathogen. These results may have important implications for the preclinical evaluation of candidate Leishmania vaccines: rather than using a single mouse strain, a panel of different inbred strains of various genetic backgrounds should be tested in parallel. The antigen that confers protection in the larger range of inbred strains may have better chances to be also protective in outbred human populations and should be selected for clinical trials. PMID:19726616

  12. Comparative evaluation of two vaccine candidates against experimental leishmaniasis due to Leishmania major infection in four inbred mouse strains.

    PubMed

    Benhnini, Fouad; Chenik, Mehdi; Laouini, Dhafer; Louzir, Hechmi; Cazenave, Pierre André; Dellagi, Koussay

    2009-11-01

    Experimental leishmaniasis in BALB/c and C57BL/6 mice are the most investigated murine models that were used for the preclinical evaluation of Leishmania vaccine candidates. We have previously described two new inbred mouse strains named PWK and MAI issued from feral founders that also support the development of experimental leishmaniasis due to L. major. In this study, we sought to determine whether different mouse inbred strains generate concordant or discordant results when used to evaluate the potential of Leishmania proteins to protect against experimental leishmaniasis. To this end, two Leishmania proteins, namely, LACK (for Leishmania homolog of receptor for activated C kinase) and LmPDI (for L. major protein disulfide isomerase) were compared for their capacity to protect against experimental leishmaniasis in PWK, MAI, BALB/c, and C57BL/6 inbred mouse strains. Our data show that the capacity of Leishmania proteins to confer protection depends on the mouse strain used, stressing the important role played by the genetic background in shaping the immune response against the pathogen. These results may have important implications for the preclinical evaluation of candidate Leishmania vaccines: rather than using a single mouse strain, a panel of different inbred strains of various genetic backgrounds should be tested in parallel. The antigen that confers protection in the larger range of inbred strains may have better chances to be also protective in outbred human populations and should be selected for clinical trials.

  13. [In silico, in vitro, in omic experimental models and drug safety evaluation].

    PubMed

    Claude, Nancy; Goldfain-Blanc, Françoise; Guillouzo, André

    2009-01-01

    Over the last few decades, toxicology has benefited from scientific, technical, and bioinformatic developments relating to patient safety assessment during clinical and drug marketing studies. Based on this knowledge, new in silico, in vitro, and "omic" experimental models are emerging. Although these models cannot currently replace classic safety evaluations performed on laboratory animals, they allow compounds with unacceptable toxicity to be rejected in the early stages of drug development, thereby reducing the number of laboratory animals needed. In addition, because these models are particularly adapted to mechanistic studies, they can help to improve the relevance of the data obtained, thus enabling better prevention and screening of the adverse effects that may occur in humans. Much progress remains to be done, especially in the field of validation. Nevertheless, current efforts by industrial, academic laboratories, and regulatory agencies should, in coming years, significantly improve preclinical drug safety evaluation thanks to the integration of these new methods into the drug research and development process.

  14. Theoretical and experimental evaluation of effective stress-induced sorption capacity change and its influence on coal permeability

    NASA Astrophysics Data System (ADS)

    Li, Chengwu; Dong, Lihui; Xu, Xiaomeng; Hu, Po; Tian, Jianwei; Zhang, Yihuai; Yang, Leilei

    2017-06-01

    The gas sorption effect is an important factor affecting the gas permeability of a coal seam, which has been proved in many previous experimental measurements and analytical permeability studies. However, the sorption capacity of coal is usually not static due to the complexity of external stress variation and internal gas media features. The stress-induced sorption capacity variation and its effect on the coal permeability change have not been fully identified yet. Thus, in this paper we present a preliminary evaluation of the stress-induced sorption capacity change by introducing the adsorption capacity modified term, and an experiment is carried out to verify the influence of the altered effective stress on coal permeability. Langmuir-like adsorption deformation constant parameters were combined into the modified coal permeability model and were given values to fully estimate the influence on permeability caused by the modification term. We found that different change modes of effective stress would yield different change effects on the permeability, that is, with the same effective stress change amount, the altered external stress-induced change had less influence than the altered-pore pressure-induced change; however, both modes demonstrated that the model taking sorption capacity change into consideration is more consistent with the experimental data. The effect of sorption capacity change on coal permeability variation was also found to be tightly connected with the physical and mechanical properties of the coal itself. It is proved that considering stress-induced sorption ability change has a critical role in characterizing the permeability variation of coal.

  15. 48 CFR 247.372 - DD Form 1654, Evaluation of Transportation Cost Factors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false DD Form 1654, Evaluation... Transportation in Supply Contracts 247.372 DD Form 1654, Evaluation of Transportation Cost Factors. Contracting personnel may use the DD Form 1654 to furnish information to the transportation office for development of...

  16. A Human Factors Evaluation of the Space Shuttle Cockpit Avionics Upgrade

    DTIC Science & Technology

    2012-09-01

    cockpit design . This study assesses the CAU design employing human factors principles, evaluates baseline and CAU simulation data, and traces MW and SA...differences back to CAU design modifications. Significant improvements were found in all measures and across all conditions. These improvements were...found to be greater for ascent scenarios than for entry. From the findings, recommendations for the design and evaluation of future spacecraft

  17. Instream-Flow Analysis for the Luquillo Experimental Forest, Puerto Rico: Methods and Analysis

    Treesearch

    F.N. Scatena; S.L. Johnson

    2001-01-01

    This study develops two habitat-based approaches for evaluating instream-flow requirements within the Luquillo Experimental Forest in northeastern Puerto Rico. The analysis is restricted to instream-flow requirements in upland streams dominated by the common communities of freshwater decapods. In headwater streams, pool volume was the most consistent factor...

  18. Human Factors Report: TMA Operational Evaluations 1996 and 1998

    NASA Technical Reports Server (NTRS)

    Lee, Katharine K.; Quinn, Cheryl M.; Hoang, Ty; Sanford, Beverly D.

    2000-01-01

    The Traffic Management Advisor (TMA) is a component of the Center-TRACON Automation System (CTAS), a suite of decision-support tools for the air traffic control (ATC) environment which is being developed at NASA Ames Research Center. TMA has been operational at the ATC facilities in Dallas/Fort Worth, Texas, since an operational field evaluation in 1996. The Operational Evaluation demonstrated significant benefits, including an approximately 5 percent increase in airport capacity. This report describes the human factors results from the 1996 Operational Evaluation and an investigation of TMA usage performed two years later, during the 1998 TMA Daily Use Field Survey. The results described are instructive for CTAS focused development, and provide valuable lessons for future research in ATC decision-support tools where it is critical to merge a well-defined, complex work environment with advanced automation.

  19. Interactions between Age, Sex, and Hormones in Experimental Ischemic Stroke

    PubMed Central

    Liu, Fudong; McCullough, Louise D.

    2012-01-01

    Age, sex, and gonadal hormones have profound effects on ischemic stroke outcomes, although how these factors impact basic stroke pathophysiology remains unclear. There is a plethora of inconsistent data reported throughout the literature, primarily due to differences in the species examined, the timing and methods used to evaluate injury, the models used, and confusion regarding differences in stroke incidence as seen in clinical populations versus effects on acute neuroprotection or neurorepair in experimental stroke models. Sex and gonadal hormone exposure have considerable independent impact on stroke outcome, but these factors also interact with each other, and the contribution of each differs throughout the lifespan. The contribution of sex and hormones to experimental stroke will be the focus of this review. Recent advances and our current understanding of age, sex, and hormone interactions in ischemic stroke with a focus on inflammation will be discussed. PMID:23068990

  20. A New Dual-Pore Formation Factor Model: A Percolation Network Study and Comparison to Experimental Data

    NASA Astrophysics Data System (ADS)

    Tang, Y. B.; Li, M.; Bernabe, Y.

    2014-12-01

    We modeled the electrical transport behavior of dual-pore carbonate rocks in this paper. Based on experimental data of a carbonate reservoir in China, we simply considered the low porosity samples equivalent to the matrix (micro-pore system) of the high porosity samples. For modeling the bimodal porous media, we considered that the matrix is homogeneous and interconnected. The connectivity and the pore size distribution of macro-pore system are varied randomly. Both pore systems are supposed to act electrically in parallel, connected at the nodes, where the fluid exchange takes place, an approach previously used by Bauer et al. (2012). Then, the effect of the properties of matrix, the pore size distribution and connectivity of macro-pore system on petrophysical properties of carbonates can be investigated. We simulated electrical current through networks in three-dimensional simple cubic (SC) and body-center cubic (BCC) with different coordination numbers and different pipe radius distributions of macro-pore system. Based on the simulation results, we found that the formation factor obeys a "universal" scaling relationship (i.e. independent of lattice type), 1/F∝eγz, where γ is a function of the normalized standard deviation of the pore radius distribution of macro-pore system and z is the coordination number of macro-pore system. This relationship is different from the classic "universal power law" in percolation theory. A formation factor model was inferred on the basis of the scaling relationship mentioned above and several scale-invariant quantities (such as hydraulic radius rH and throat length l of macro-pore). Several methods were developed to estimate corresponding parameters of the new model with conventional core analyses. It was satisfactorily tested against experimental data, including some published experimental data. Furthermore, the relationship between water saturation and resistivity in dual-pore carbonates was discussed based on the new model.

  1. Experimental evaluation of thermal ratcheting behavior in UO2 fuel elements

    NASA Technical Reports Server (NTRS)

    Phillips, W. M.

    1973-01-01

    The effects of thermal cycling of UO2 at high temperatures has been experimentally evaluated to determine the rates of distortion of UO2/clad fuel elements. Two capsules were rested in the 1500 C range, one with a 50 C thermal cycle, the other with a 100 C thermal cycle. It was observed that eight hours at the lower cycle temperature produced sufficient UO2 redistribution to cause clad distortion. The amount of distortion produced by the 100 C cycle was less than double that produced by the 50 C, indicating smaller thermal cycles would result in clad distortion. An incubation period was observed to occur before the onset of distortion with cycling similar to fuel swelling observed in-pile at these temperatures.

  2. Fuzzy comprehensive evaluation of multiple environmental factors for swine building assessment and control.

    PubMed

    Xie, Qiuju; Ni, Ji-Qin; Su, Zhongbin

    2017-10-15

    In confined swine buildings, temperature, humidity, and air quality are all important for animal health and productivity. However, the current swine building environmental control is only based on temperature; and evaluation and control methods based on multiple environmental factors are needed. In this paper, fuzzy comprehensive evaluation (FCE) theory was adopted for multi-factor assessment of environmental quality in two commercial swine buildings using real measurement data. An assessment index system and membership functions were established; and predetermined weights were given using analytic hierarchy process (AHP) combined with knowledge of experts. The results show that multi-factors such as temperature, humidity, and concentrations of ammonia (NH 3 ), carbon dioxide (CO 2 ), and hydrogen sulfide (H 2 S) can be successfully integrated in FCE for swine building environment assessment. The FCE method has a high correlation coefficient of 0.737 compared with the method of single-factor evaluation (SFE). The FCE method can significantly increase the sensitivity and perform an effective and integrative assessment. It can be used as part of environmental controlling and warning systems for swine building environment management to improve swine production and welfare. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. The Captive Helicopter as a Training Device: Experimental Evaluation of a Concept. Technical Report 68-9.

    ERIC Educational Resources Information Center

    Caro, Paul W., Jr.; And Others

    As part of the Army's effort to use synthetic devices to improve training, researchers evaluated a captive helicopter attached to a ground effects machine. Experimental groups received varying amounts of pre-flight practice tasks designed to develop flight skills, while control groups received no device training. Student flight performance during…

  4. The application of MATLAB-based analytic hierarchy process in Hainan residential quarter function factor evaluation

    NASA Astrophysics Data System (ADS)

    Qiu, Dongdong; Liu, Peiqi

    2017-04-01

    Since being designated as an international tourist island, Hainan has become an overwhelmingly favored choice of real estate investment. This paper first constructed Hainan residential quarter function factor index system, then evaluated relevant factors, and finally solved the problem of factor importance ranking. In this specific case, the software MATLAB was used to facilitate AHP calculation. The evaluation results have guiding and referential value to both real estate developers and residential consumers.

  5. Probabilistic Multi-Factor Interaction Model for Complex Material Behavior

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.; Abumeri, Galib H.

    2008-01-01

    The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the launch external tanks. The multi-factor has sufficient degrees of freedom to evaluate a large number of factors that may contribute to the divot ejection. It also accommodates all interactions by its product form. Each factor has an exponent that satisfies only two points, the initial and final points. The exponent describes a monotonic path from the initial condition to the final. The exponent values are selected so that the described path makes sense in the absence of experimental data. In the present investigation the data used was obtained by testing simulated specimens in launching conditions. Results show that the MFIM is an effective method of describing the divot weight ejected under the conditions investigated.

  6. Probabilistic Multi-Factor Interaction Model for Complex Material Behavior

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.; Abumeri, Galib H.

    2008-01-01

    The Multi-Factor Interaction Model (MFIM) is used to evaluate the divot weight (foam weight ejected) from the launch external tanks. The multi-factor has sufficient degrees of freedom to evaluate a large number of factors that may contribute to the divot ejection. It also accommodates all interactions by its product form. Each factor has an exponent that satisfies only two points the initial and final points. The exponent describes a monotonic path from the initial condition to the final. The exponent values are selected so that the described path makes sense in the absence of experimental data. In the present investigation, the data used was obtained by testing simulated specimens in launching conditions. Results show that the MFIM is an effective method of describing the divot weight ejected under the conditions investigated.

  7. Re-evaluation of the correction factors for the GROVEX

    NASA Astrophysics Data System (ADS)

    Ketelhut, Steffen; Meier, Markus

    2018-04-01

    The GROVEX (GROssVolumige EXtrapolationskammer, large-volume extrapolation chamber) is the primary standard for the dosimetry of low-dose-rate interstitial brachytherapy at the Physikalisch-Technische Bundesanstalt (PTB). In the course of setup modifications and re-measuring of several dimensions, the correction factors have been re-evaluated in this work. The correction factors for scatter and attenuation have been recalculated using the Monte Carlo software package EGSnrc, and a new expression has been found for the divergence correction. The obtained results decrease the measured reference air kerma rate by approximately 0.9% for the representative example of a seed of type Bebig I25.S16C. This lies within the expanded uncertainty (k  =  2).

  8. Psychological Factors Predict Local and Referred Experimental Muscle Pain: A Cluster Analysis in Healthy Adults

    PubMed Central

    Lee, Jennifer E.; Watson, David; Frey-Law, Laura A.

    2012-01-01

    Background Recent studies suggest an underlying three- or four-factor structure explains the conceptual overlap and distinctiveness of several negative emotionality and pain-related constructs. However, the validity of these latent factors for predicting pain has not been examined. Methods A cohort of 189 (99F; 90M) healthy volunteers completed eight self-report negative emotionality and pain-related measures (Eysenck Personality Questionnaire-Revised; Positive and Negative Affect Schedule; State-Trait Anxiety Inventory; Pain Catastrophizing Scale; Fear of Pain Questionnaire; Somatosensory Amplification Scale; Anxiety Sensitivity Index; Whiteley Index). Using principal axis factoring, three primary latent factors were extracted: General Distress; Catastrophic Thinking; and Pain-Related Fear. Using these factors, individuals clustered into three subgroups of high, moderate, and low negative emotionality responses. Experimental pain was induced via intramuscular acidic infusion into the anterior tibialis muscle, producing local (infusion site) and/or referred (anterior ankle) pain and hyperalgesia. Results Pain outcomes differed between clusters (multivariate analysis of variance and multinomial regression), with individuals in the highest negative emotionality cluster reporting the greatest local pain (p = 0.05), mechanical hyperalgesia (pressure pain thresholds; p = 0.009) and greater odds (2.21 OR) of experiencing referred pain compared to the lowest negative emotionality cluster. Conclusion Our results provide support for three latent psychological factors explaining the majority of the variance between several pain-related psychological measures, and that individuals in the high negative emotionality subgroup are at increased risk for (1) acute local muscle pain; (2) local hyperalgesia; and (3) referred pain using a standardized nociceptive input. PMID:23165778

  9. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 7 : final report : thesis.

    DOT National Transportation Integrated Search

    2015-05-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 7, Final Report - Thesis. : This final report covers Tasks 1, 2, 3, 5 ...

  10. Monte Carlo and experimental determination of correction factors for gamma knife perfexion small field dosimetry measurements

    NASA Astrophysics Data System (ADS)

    Zoros, E.; Moutsatsos, A.; Pappas, E. P.; Georgiou, E.; Kollias, G.; Karaiskos, P.; Pantelis, E.

    2017-09-01

    Detector-, field size- and machine-specific correction factors are required for precise dosimetry measurements in small and non-standard photon fields. In this work, Monte Carlo (MC) simulation techniques were used to calculate the k{{Qmsr},{{Q}0}}{{fmsr},{{f}ref}} and k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} correction factors for a series of ionization chambers, a synthetic microDiamond and diode dosimeters, used for reference and/or output factor (OF) measurements in the Gamma Knife Perfexion photon fields. Calculations were performed for the solid water (SW) and ABS plastic phantoms, as well as for a water phantom of the same geometry. MC calculations for the k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} correction factors in SW were compared against corresponding experimental results for a subset of ionization chambers and diode detectors. Reference experimental OF data were obtained through the weighted average of corresponding measurements using TLDs, EBT-2 films and alanine pellets. k{{Qmsr},{{Q}0}}{{fmsr},{{f}ref}} values close to unity (within 1%) were calculated for most of ionization chambers in water. Greater corrections of up to 6.0% were observed for chambers with relatively large air-cavity dimensions and steel central electrode. A phantom correction of 1.006 and 1.024 (breaking down to 1.014 from the ABS sphere and 1.010 from the accompanying ABS phantom adapter) were calculated for the SW and ABS phantoms, respectively, adding up to k{{Qmsr},{{Q}0}}{{fmsr},{{f}ref}} corrections in water. Both measurements and MC calculations for the diode and microDiamond detectors resulted in lower than unit k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} correction factors, due to their denser sensitive volume and encapsulation materials. In comparison, higher than unit k{{Qclin},{{Q}msr}}{{fclin},{{f}msr}} results for the ionization chambers suggested field size depended dose underestimations (being significant for the 4 mm field), with magnitude depending on the combination of

  11. A Nutritional Evaluation of the Experimental Food Service System at Travis AFB, California

    DTIC Science & Technology

    1974-07-01

    food service experiment at Travis AFB, California was performed. The purpose of this evaluation was to determine the levels of selected nutrient elements provided by these meals and to compare them with established nutritional standards. In addition, the data provide for a comparison of the nutritional profiles of the meals served in the dining halls with those served in two new experimental food outlets. It is concluded that the meals served during the experiment were nutritionally adequate as compared to Air Force requirements, and that the meals served in the two new

  12. Comparison of two models for evaluation histopathology of experimental renal ischemia.

    PubMed

    Tirapelli, L F; Barione, D F; Trazzi, B F M; Tirapelli, D P C; Novas, P C; Silva, C S; Martinez, M; Costa, R S; Tucci, S; Suaid, H J; Cologna, A J; Martins, A C P

    2009-12-01

    Renal ischemia/reperfusion (I/R) injury is one of the frequent causes of acute renal failure (ARF) due to the complex, interrelated sequence of events, that result in damage to and death of kidney cells. Cells of the proximal tubular epithelium are especially susceptible to I/R injury, leading to acute tubular necrosis, which plays a pivotal role in the pathogenesis of ARF. Several models have been explicated to assess morphological changes, including those of Jabonski et al. and Goujon et al. We compared the 2 models for histopathological evaluation of 30- or 120-minute periods of renal ischemia followed by 24-hour reperfusion in rats. Several changes were observed after application of the 2 models: proximal tubular cell necrosis, loss of brush border, vacuolization, denudation of tubular basement membrane as a consequence of flattening of basal cells, and presence of intratubular exfoliated cells in the lumen of proximal convoluted tubules at various stages of degeneration (karyorexis, kariopyknosis and karyolysis). Evaluating tubular lesions after 2 periods of experimental ischemia with light microscopy allowed us to conclude that the Goujon classification better characterized the main changes in cortical renal tubules after ischemia.

  13. Experimental and FE displacement and polymerization stress of bonded restorations as a function of the C-Factor, volume and substrate stiffness.

    PubMed

    Boaro, Letícia Cristina Cidreira; Brandt, William Cunha; Meira, Josete Barbosa Cruz; Rodrigues, Flávia Pires; Palin, William M; Braga, Roberto Ruggiero

    2014-02-01

    To determine the free surface displacement of resin-composite restorations as a function of the C-Factor, volume and substrate stiffness, and to compare the results with interfacial stress values evaluated by finite element analysis (FEA). Surface displacement was determined by an extensometer using restorations with 4 or 6mm diameter and 1 or 2mm depth, prepared in either bovine teeth or glass. The maximum displacement of the free surface was monitored for 5 min from the start of photoactivation, at an acquisition rate of 1s(-1). Axisymmetric cavity models were performed by FEA. Structural stiffness and maximum stresses were investigated. For glass, displacement showed a stronger correlation with volume (r=0.771) than with C-Factor (r=0.395, p<0.001 for both). For teeth, a stronger correlation was found with C-Factor (r=0.709; p<0.001) than with volume (r=0.546, p<0.001). For similar dimensions, stress and displacement were defined by stiffness. Simultaneous increases in volume and C-Factor led to increases in stress and surface displacement. Maximum stresses were located at the cavosurface angle, internal angle (glass) and at the dentine-enamel junction (teeth). The displacement of the restoration's free surface was related to interfacial stress development. Structural stiffness seems to affect the shrinkage stress at the tooth/resin-composite interface in bonded restorations. Deep restorations are always problematic because they showed high shear stress, regardless of their width. FEA is the only tool capable of detecting shear stress due to polymerization as there is still no reliable experimental alternative. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Experimental 64Zn(d⃗,t)63Zn spectroscopic factors: Guidance for isospin-symmetry-breaking calculations

    NASA Astrophysics Data System (ADS)

    Leach, K. G.; Garrett, P. E.; Towner, I. S.; Ball, G. C.; Bildstein, V.; Brown, B. A.; Demand, G. A.; Faestermann, T.; Finlay, P.; Green, K. L.; Hertenberger, R.; Krücken, R.; Phillips, A. A.; Rand, E. T.; Sumithrarachchi, C. S.; Svensson, C. E.; Triambak, S.; Wirth, H.-F.; Wong, J.

    2013-06-01

    With the recent inclusion of core orbitals to the radial-overlap component of the isospin-symmetry-breaking (ISB) corrections for superallowed Fermi β decay, experimental data are needed to test the validity of the theoretical model. This work reports measurements of single-neutron pickup reaction spectroscopic factors into 63Zn, one neutron away from 62Zn, the superallowed daughter of 62Ga. The experiment was performed using a 22-MeV polarized deuteron beam, a Q3D magnetic spectrograph, and a cathode-strip focal-plane detector to analyze outgoing tritons at nine angles between 10∘ and 60∘. Angular distributions and vector analyzing powers were obtained for all 162 observed states in 63Zn, including 125 newly observed levels, up to an excitation energy of 4.8 MeV. Spectroscopic factors are extracted and compared to several shell-model predictions, and implications for the ISB calculations are discussed.

  15. Experimental evaluation of a MOSFET dosimeter for proton dose measurements.

    PubMed

    Kohno, Ryosuke; Nishio, Teiji; Miyagishi, Tomoko; Hirano, Eriko; Hotta, Kenji; Kawashima, Mitsuhiko; Ogino, Takashi

    2006-12-07

    The metal oxide semiconductor field-effect transistor (MOSFET) dosimeter has been widely studied for use as a dosimeter for patient dose verification. The major advantage of this detector is its size, which acts as a point dosimeter, and also its ease of use. The commercially available TN502RD MOSFET dosimeter manufactured by Thomson and Nielsen has never been used for proton dosimetry. Therefore we used the MOSFET dosimeter for the first time in proton dose measurements. In this study, the MOSFET dosimeter was irradiated with 190 MeV therapeutic proton beams. We experimentally evaluated dose reproducibility, linearity, fading effect, beam intensity dependence and angular dependence for the proton beam. Furthermore, the Bragg curve and spread-out Bragg peak were also measured and the linear-energy transfer (LET) dependence of the MOSFET response was investigated. Many characteristics of the MOSFET response for proton beams were the same as those for photon beams reported in previous papers. However, the angular MOSFET responses at 45, 90, 135, 225, 270 and 315 degrees for proton beams were over-responses of about 15%, and moreover the MOSFET response depended strongly on the LET of the proton beam. This study showed that the angular dependence and LET dependence of the MOSFET response must be considered very carefully for quantitative proton dose evaluations.

  16. Experimental Evaluation of the Thermal Performance of a Water Shield for a Surface Power Reactor

    NASA Technical Reports Server (NTRS)

    Pearson, J. Boise; Stewart, Eric T.; Reid, Robert S.

    2007-01-01

    A water based shielding system is being investigated for use on initial lunar surface power systems. The use of water may lower overall cost (as compared to development cost for other materials) and simplify operations in the setup and handling. The thermal hydraulic performance of the shield is of significant interest. The mechanism for transferring heat through the shield is natural convection. Natural convection in a representative lunar surface reactor shield design is evaluated at various power levels in the Water Shield Testbed (WST) at the NASA Marshall Space Flight Center. The experimental data from the WST is used to anchor a CFD model. Performance of a water shield on the lunar surface is then predicted by CFD models anchored to test data. The accompanying viewgraph presentation includes the following topics: 1) Testbed Configuration; 2) Core Heater Placement and Instrumentation; 3) Thermocouple Placement; 4) Core Thermocouple Placement; 5) Outer Tank Thermocouple Placement; 6) Integrated Testbed; 7) Methodology; 8) Experimental Results: Core Temperatures; 9) Experimental Results; Outer Tank Temperatures; 10) CFD Modeling; 11) CFD Model: Anchored to Experimental Results (1-g); 12) CFD MOdel: Prediction for 1/6-g; and 13) CFD Model: Comparison of 1-g to 1/6-g.

  17. A comprehensive evaluation of the toxicology of monogram inks added to experimental cigarettes.

    PubMed

    Smith, Donna C; Wiecinski, Paige N; Coggins, Christopher R E; Banty, Tamara H; Oldham, Michael J

    2013-01-01

    Cigarettes often have a small identifying mark (monogram) printed either on the cigarette paper toward the filter end of the cigarette or on the tipping paper. A battery of tests was used to compare the toxicology of mainstream smoke from experimental cigarettes manufactured with different monogram inks. Cigarettes with different concentrations of different pigments were compared with cigarettes without ink, and with a control ink. Smoke from each of the experimental cigarettes was evaluated using analytical chemistry and in vitro bacterial mutagenicity (Salmonella, five strains, ± S9) and cytotoxicity (neutral red uptake) assays. No differences were observed between experimental cigarettes printed with three different pigment loads of iron oxide-based Black pigment and non-printed cigarettes. In general, no dose response was observed. However, increases in certain smoke constituents were found to correlate with Pigment Yellow 14 (also known as benzidine yellow) and Pigment Blue 15 (copper phthalocyanine). Increases in bacterial mutagenicity were observed for high-level print of Pigment Yellow 14 in TA98 and TA1537 and the high-level print of Pigment Blue 15 in TA98. In vitro cytotoxicity of mainstream smoke was unaffected by the presence of monogram ink on cigarettes. Statistically significant dose-responsive constituent changes and an increase in mutagenicity were observed with inclusion of Pigment Yellow 14 and Pigment Blue 15. Other pigments showed minimal toxicological activity.

  18. Study on Factors of Favorable Wet Cotton Hand Towels “Oshibori”

    NASA Astrophysics Data System (ADS)

    Soeta, Yasuhiro; Kitamoto, Takuma; Hasegawa, Hiroshi; Kasuga, Masao

    In the present study, we evaluated important factors of the feelings of comfort associated with wet cotton hand towels, or oshibori. First, the following adjectives were extracted as words used to evaluate the characteristics of the oshibori: “large,” “pretty,” “comfortable,” “high-grade,” “shapely,” “soft,” “favorite,” “thick,” “clean,” “moist,” “luxurious,” “heavy,” “strong,” “safe,” “good-touch,” and “rare.” We then conducted a subjective evaluation of 25 kinds of oshibori of various sizes and thicknesses. Forty males and twenty-four females, ranging in age from their twenties to fifties, participated in the experiment. Each subject evaluated the oshibori by grading them from one to five based on the extracted descriptive characteristics. Factor analysis was conducted on the experimental results and the following three factors were extracted; the first factor defined as “dignity factor,” the second factor defined as “preference factor,” and the third factor defined as “touch factor.” The score for dignity increased as the size of the oshibori increased. The score for preference was high when the size of the oshibori was between 25 cm × 25 cm and 30 cm × 30 cm. These results suggest that subjects felt high-class if the size of the oshibori was greater than 30 cm × 30 cm, but subjects most preferred oshibori that were between 25 cm × 25 cm and 30 cm × 30 cm. No notable trend was found between the thickness of oshibori and the three factors. We then analyzed the experimental data focusing on the following viewpoints; “gender” and “generation.” of the subjects, and discussed how these factors effected on the feelings of oshibori using the Mann-Whitney U test and the Kruskal-Wallis H test. The analyzed results show that the female subjects tended to evaluate more highly on the evaluation words of “thick,” “moist,” and “heavy,” that the evaluations of “large,”

  19. Experimental flexible pavements.

    DOT National Transportation Integrated Search

    1971-01-01

    A program of construction and the performance evaluation of three major Virginia experimental flexible pavements is reported. The objective of the program was to evaluate the performance of pavements incorporating new or timely design concepts and to...

  20. Factors influencing sorption of ciprofloxacin onto activated sludge: experimental assessment and modelling implications.

    PubMed

    Polesel, Fabio; Lehnberg, Kai; Dott, Wolfgang; Trapp, Stefan; Thomas, Kevin V; Plósz, Benedek Gy

    2015-01-01

    Many of the pharmaceuticals and personal care products occurring in municipal sewage are ionizing substances, and their partitioning behaviour is affected by ionic interactions with solid matrices. In activated sludge systems, such interactions have currently not been adequately understood and described, particularly for zwitterionic chemicals. Here we present an assessment of the effects of pH and iron salt dosing on the sorption of ciprofloxacin onto activated sludge using laboratory experiments and full-scale fate modelling. Experimental results were described with Freundlich isotherms and showed that non-linear sorption occurred under all the conditions tested. The greatest sorption potential was measured at pH=7.4, at which ciprofloxacin is speciated mostly as zwitterion. Iron salt dosing increased sorption under aerobic and, to a lesser extent, anoxic conditions, whereas no effect was registered under anaerobic conditions. The activated sludge model for xenobiotics (ASM-X) was extended with Freundlich-based sorption kinetics and used to predict the fate of ciprofloxacin in a wastewater treatment plant (WWTP). Scenario simulations, using experimental Freundlich parameters, were used to identify whether the assessed factors caused a significant increase of aqueous ciprofloxacin concentration in full-scale bioreactors. Simulation results suggest that a pH increase, rather than a reduction in iron salt dosing, could be responsible for a systematic deterioration of sorption of ciprofloxacin in the WWTP. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Preclinical Performance Evaluation of Percutaneous Glucose Biosensors: Experimental Considerations and Recommendations.

    PubMed

    Soto, Robert J; Schoenfisch, Mark H

    2015-06-17

    The utility of continuous glucose monitoring devices remains limited by an obstinate foreign body response (FBR) that degrades the analytical performance of the in vivo sensor. A number of novel materials that resist or delay the FBR have been proposed as outer, tissue-contacting glucose sensor membranes as a strategy to improve sensor accuracy. Traditionally, researchers have examined the ability of a material to minimize the host response by assessing adsorbed cell morphology and tissue histology. However, these techniques do not adequately predict in vivo glucose sensor function, necessitating sensor performance evaluation in a relevant animal model prior to human testing. Herein, the effects of critical experimental parameters, including the animal model and data processing methods, on the reliability and usefulness of preclinical sensor performance data are considered. © 2015 Diabetes Technology Society.

  2. Evaluation of a Consistent LES/PDF Method Using a Series of Experimental Spray Flames

    NASA Astrophysics Data System (ADS)

    Heye, Colin; Raman, Venkat

    2012-11-01

    A consistent method for the evolution of the joint-scalar probability density function (PDF) transport equation is proposed for application to large eddy simulation (LES) of turbulent reacting flows containing evaporating spray droplets. PDF transport equations provide the benefit of including the chemical source term in closed form, however, additional terms describing LES subfilter mixing must be modeled. The recent availability of detailed experimental measurements provide model validation data for a wide range of evaporation rates and combustion regimes, as is well-known to occur in spray flames. In this work, the experimental data will used to investigate the impact of droplet mass loading and evaporation rates on the subfilter scalar PDF shape in comparison with conventional flamelet models. In addition, existing model term closures in the PDF transport equations are evaluated with a focus on their validity in the presence of regime changes.

  3. An experimental clinical evaluation of EIT imaging with ℓ1 data and image norms.

    PubMed

    Mamatjan, Yasin; Borsic, Andrea; Gürsoy, Doga; Adler, Andy

    2013-09-01

    Electrical impedance tomography (EIT) produces an image of internal conductivity distributions in a body from current injection and electrical measurements at surface electrodes. Typically, image reconstruction is formulated using regularized schemes in which ℓ2-norms are used for both data misfit and image prior terms. Such a formulation is computationally convenient, but favours smooth conductivity solutions and is sensitive to outliers. Recent studies highlighted the potential of ℓ1-norm and provided the mathematical basis to improve image quality and robustness of the images to data outliers. In this paper, we (i) extended a primal-dual interior point method (PDIPM) algorithm to 2.5D EIT image reconstruction to solve ℓ1 and mixed ℓ1/ℓ2 formulations efficiently, (ii) evaluated the formulation on clinical and experimental data, and (iii) developed a practical strategy to select hyperparameters using the L-curve which requires minimum user-dependence. The PDIPM algorithm was evaluated using clinical and experimental scenarios on human lung and dog breathing with known electrode errors, which requires a rigorous regularization and causes the failure of reconstruction with an ℓ2-norm solution. The results showed that an ℓ1 solution is not only more robust to unavoidable measurement errors in a clinical setting, but it also provides high contrast resolution on organ boundaries.

  4. A Short-Term, Quasi-Experimental Evaluation of D.A.R.E.'s Revised Elementary School Curriculum

    ERIC Educational Resources Information Center

    Vincus, Amy A.; Ringwalt, Chris; Harris, Melissa S.; Shamblen, Stephen R.

    2010-01-01

    We present the short-term results of a quasi-experimental evaluation of the revised D. A. R. E. (Drug Abuse Resistance Education) curriculum. Study outcomes examined were D. A. R. E.'s effects on three substances, namely students' lifetime and 30-day use of tobacco, alcohol, and marijuana, as well as their school attendance and academic…

  5. Experimental evaluation of fluctuating density and radiated noise from a high temperature jet

    NASA Technical Reports Server (NTRS)

    Massier, P. F.; Parthasarathy, S. P.; Cuffel, R. F.

    1973-01-01

    An experimental investigation has been conducted to characterize the fluctuating density within a high-temperature (1100 K) subsonic jet and to characterize by the noise radiated to the surroundings. Cross correlations obtained by introducing time delay to the signals detected from spatially separated crossed laser beams set up as a Schlieren system were used to determine radial and axial distributions of the convection velocity of the moving noise sources (eddies). In addition, the autocorrelation of the fluctuating density was evaluated in the moving frame of reference of the eddies. Also, the autocorrelation of the radiated noise in the moving reference frame was evaluated from cross correlations by introducing time delay to the signals detected by spatially separated pairs of microphones. Radial distributions of the mean velocity were obtained from measurements of the stagnation temperature, and stagnation and static pressures with the use of probes.

  6. Antiangiogenic activity of vitexicarpine in experimentally induced hepatocellular carcinoma: Impact on vascular endothelial growth factor pathway.

    PubMed

    Hassoun, Shimaa M; Abdel-Rahman, Noha; Eladl, Entsar I; El-Shishtawy, Mamdouh M

    2017-06-01

    Angiogenesis plays important roles in progression of hepatocellular carcinoma. The antiangiogenic mechanisms of vitexicarpine are not fully defined. Therefore, we conducted the following study to evaluate the antiangiogenic mechanism and antitumor activity of vitexicarpine in vivo model of hepatocellular carcinoma through modulation of vascular endothelial growth factor signaling pathway. Hepatocellular carcinoma was induced in Sprague Dawley rats by thioacetamide. Hepatocellular carcinoma was assessed by measuring serum alpha-fetoprotein and investigating liver sections stained with hematoxylin/eosin. Hepatocellular carcinoma rats were injected with vitexicarpine (150 mg/kg) for 2 weeks. Hepatic vascular endothelial growth factor was measured by enzyme-linked immunosorbent assay. Protein and expression of hepatic phospho-Ser473-AKT (p-AKT) and phospho-Tyr419-Src (p-Src) were determined. The apoptotic pathway was evaluated by assessment of protein expression of caspase-3. Vitexicarpine increased rats' survival time and decreased serum alpha-fetoprotein as well as it ameliorated fibrosis and massive hepatic tissue breakdown. It attenuated hepatocellular carcinoma-induced protein and gene expression of vascular endothelial growth factor, p-AKT, p-Src, and caspase-3. In conclusion, this study suggests that vitexicarpine possesses both antiangiogenic and antitumor activities through inhibition of vascular endothelial growth factor, p-AKT/AKT, and p-Src with subsequent inhibition of apoptotic pathway.

  7. Optimization of formulation variables of benzocaine liposomes using experimental design.

    PubMed

    Mura, Paola; Capasso, Gaetano; Maestrelli, Francesca; Furlanetto, Sandra

    2008-01-01

    This study aimed to optimize, by means of an experimental design multivariate strategy, a liposomal formulation for topical delivery of the local anaesthetic agent benzocaine. The formulation variables for the vesicle lipid phase uses potassium glycyrrhizinate (KG) as an alternative to cholesterol and the addition of a cationic (stearylamine) or anionic (dicethylphosphate) surfactant (qualitative factors); the percents of ethanol and the total volume of the hydration phase (quantitative factors) were the variables for the hydrophilic phase. The combined influence of these factors on the considered responses (encapsulation efficiency (EE%) and percent drug permeated at 180 min (P%)) was evaluated by means of a D-optimal design strategy. Graphic analysis of the effects indicated that maximization of the selected responses requested opposite levels of the considered factors: For example, KG and stearylamine were better for increasing EE%, and cholesterol and dicethylphosphate for increasing P%. In the second step, the Doehlert design, applied for the response-surface study of the quantitative factors, pointed out a negative interaction between percent ethanol and volume of the hydration phase and allowed prediction of the best formulation for maximizing drug permeation rate. Experimental P% data of the optimized formulation were inside the confidence interval (P < 0.05) calculated around the predicted value of the response. This proved the suitability of the proposed approach for optimizing the composition of liposomal formulations and predicting the effects of formulation variables on the considered experimental response. Moreover, the optimized formulation enabled a significant improvement (P < 0.05) of the drug anaesthetic effect with respect to the starting reference liposomal formulation, thus demonstrating its actually better therapeutic effectiveness.

  8. Engineering platform and experimental protocol for design and evaluation of a neurally-controlled powered transfemoral prosthesis.

    PubMed

    Zhang, Fan; Liu, Ming; Harper, Stephen; Lee, Michael; Huang, He

    2014-07-22

    To enable intuitive operation of powered artificial legs, an interface between user and prosthesis that can recognize the user's movement intent is desired. A novel neural-machine interface (NMI) based on neuromuscular-mechanical fusion developed in our previous study has demonstrated a great potential to accurately identify the intended movement of transfemoral amputees. However, this interface has not yet been integrated with a powered prosthetic leg for true neural control. This study aimed to report (1) a flexible platform to implement and optimize neural control of powered lower limb prosthesis and (2) an experimental setup and protocol to evaluate neural prosthesis control on patients with lower limb amputations. First a platform based on a PC and a visual programming environment were developed to implement the prosthesis control algorithms, including NMI training algorithm, NMI online testing algorithm, and intrinsic control algorithm. To demonstrate the function of this platform, in this study the NMI based on neuromuscular-mechanical fusion was hierarchically integrated with intrinsic control of a prototypical transfemoral prosthesis. One patient with a unilateral transfemoral amputation was recruited to evaluate our implemented neural controller when performing activities, such as standing, level-ground walking, ramp ascent, and ramp descent continuously in the laboratory. A novel experimental setup and protocol were developed in order to test the new prosthesis control safely and efficiently. The presented proof-of-concept platform and experimental setup and protocol could aid the future development and application of neurally-controlled powered artificial legs.

  9. Roles of macrophage migration inhibitory factor in Guillain-Barré syndrome and experimental autoimmune neuritis: beneficial or harmful?

    PubMed

    Shen, Donghui; Lang, Yue; Chu, Fengna; Wu, Xiujuan; Wang, Ying; Zheng, Xiangyu; Zhang, Hong-Liang; Zhu, Jie; Liu, Kangding

    2018-06-11

    Macrophage migration inhibitory factor (MIF) plays an important role in the pathogenesis of Guillain-Barré syndrome (GBS) and its animal model experimental autoimmune neuritis (EAN), which may offer an opportunity for the development of the novel therapeutic strategies for GBS. Areas covered: 'macrophage migration inhibitory factor' and 'Guillain-Barré syndrome' were used as keywords to search for related publications on Pub-Med, National Center for Biotechnology Information (NCBI), USA. MIF is involved in the etiology of various inflammatory and autoimmune disorders. However, the roles of MIF in GBS and EAN have not been summarized in the publications we identified. Therefore, in this review, we described and analyzed the major roles of MIF in GBS/EAN. Primarily, this molecule aggravates the inflammatory responses in this disorder. However, multiple studies indicated a protective role of MIF in GBS. The potential of MIF as a therapeutic target in GBS has been recently demonstrated in experimental and clinical studies, although clinical trials have been unavailable to date. Expert opinion: MIF plays a critical role in the initiation and progression of GBS and EAN, and it may represent a potential therapeutic target for GBS.

  10. Experimental Psychopathology Paradigms for Alcohol Use Disorders: Applications for Translational Research

    PubMed Central

    Bujarski, Spencer; Ray, Lara A.

    2016-01-01

    In spite of high prevalence and disease burden, scientific consensus on the etiology and treatment of Alcohol Use Disorder (AUD) has yet to be reached. The development and utilization of experimental psychopathology paradigms in the human laboratory represents a cornerstone of AUD research. In this review, we describe and critically evaluate the major experimental psychopathology paradigms developed for AUD, with an emphasis on their implications, strengths, weaknesses, and methodological considerations. Specifically we review alcohol administration, self-administration, cue-reactivity, and stress-reactivity paradigms. We also provide an introduction to the application of experimental psychopathology methods to translational research including genetics, neuroimaging, pharmacological and behavioral treatment development, and translational science. Through refining and manipulating key phenotypes of interest, these experimental paradigms have the potential to elucidate AUD etiological factors, improve the efficiency of treatment developments, and refine treatment targets thus advancing precision medicine. PMID:27266992

  11. Experimental psychopathology paradigms for alcohol use disorders: Applications for translational research.

    PubMed

    Bujarski, Spencer; Ray, Lara A

    2016-11-01

    In spite of high prevalence and disease burden, scientific consensus on the etiology and treatment of Alcohol Use Disorder (AUD) has yet to be reached. The development and utilization of experimental psychopathology paradigms in the human laboratory represents a cornerstone of AUD research. In this review, we describe and critically evaluate the major experimental psychopathology paradigms developed for AUD, with an emphasis on their implications, strengths, weaknesses, and methodological considerations. Specifically we review alcohol administration, self-administration, cue-reactivity, and stress-reactivity paradigms. We also provide an introduction to the application of experimental psychopathology methods to translational research including genetics, neuroimaging, pharmacological and behavioral treatment development, and translational science. Through refining and manipulating key phenotypes of interest, these experimental paradigms have the potential to elucidate AUD etiological factors, improve the efficiency of treatment developments, and refine treatment targets thus advancing precision medicine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Striatal increase of neurotrophic factors as a mechanism of nicotine protection in experimental parkinsonism.

    PubMed

    Maggio, R; Riva, M; Vaglini, F; Fornai, F; Racagni, G; Corsini, G U

    1997-01-01

    The repeated finding of an apparent protective effect of cigarette smoking on the risk of Parkinson's disease is one of the few consistent results in the epidemiology of this disorder. Among the innumerous substances that originate from tobacco smoke, nicotine is by far the most widely studied, and the most likely candidate for a protective effect against neuronal degeneration in Parkinson's disease. Nicotine is a natural alkaloid that has considerable stimulatory effects on the central nervous system (CNS). Its effects on the CNS are mediated by the activation of neuronal heteromeric acetylcholine-gated ion channel receptors (nAChR, also termed nicotinic acetylcholine receptors). In the present study, we describe the neuroprotective effects of (-)nicotine in two animal models of parkinsonism: the diethyldithiocarbamate (DDC)-induced enhancement of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) toxicity in mice, and the methamphetamine-induced neurotoxicity in rats and mice. In parallel experiments, we found that (-)nicotine induces the basic fibroblast growth factor (FGF-2) and the brain-derived neurotrophic factor (BDNF) in rat striatum. As FGF-2 and BDNF have been reported to be neuroprotective for dopaminergic cells, our data indicate that the increase in neurotrophic factors is a possible mechanism by which (-)nicotine protects from experimental parkinsonisms. Moreover, they suggest that nAChR agonists could be of potential benefit in the progression of Parkinson's disease.

  13. Evaluating a Computational Model of Social Causality and Responsibility

    DTIC Science & Technology

    2006-01-01

    Evaluating a Computational Model of Social Causality and Responsibility Wenji Mao University of Southern California Institute for Creative...empirically evaluate a computa- tional model of social causality and responsibility against human social judgments. Results from our experimental...developed a general computational model of social cau- sality and responsibility [10, 11] that formalizes the factors people use in reasoning about

  14. Experimental evaluation of a miniature MR device for a wide range of human perceivable haptic sensations

    NASA Astrophysics Data System (ADS)

    Yang, Tae-Heon; Koo, Jeong-Hoi

    2017-12-01

    Humans can experience a realistic and vivid haptic sensations by the sense of touch. In order to have a fully immersive haptic experience, both kinaesthetic and vibrotactile information must be presented to human users. Currently, little haptic research has been performed on small haptic actuators that can covey both vibrotactile feedback based on the frequency of vibrations up to the human-perceivable limit and multiple levels of kinaesthetic feedback rapidly. Therefore, this study intends to design a miniature haptic device based on MR fluid and experimentally evaluate its ability to convey vibrotactile feedback up to 300 Hz along with kinaesthetic feedback. After constructing a prototype device, a series of testing was performed to evaluate its performance of the prototype using an experimental setup, consisting of a precision dynamic mechanical analyzer and an accelerometer. The kinaesthetic testing results show that the prototype device can provide the force rate up to 89% at 5 V (360 mA), which can be discretized into multiple levels of ‘just noticeable difference’ force rate, indicating that the device can convey a wide range of kinaesthetic sensations. To evaluate the high frequency vibrotactile feedback performance of the device, its acceleration responses were measured and processed using the FFT analysis. The results indicate that the device can convey high frequency vibrotactile sensations up to 300 Hz with the sufficiently large intensity of accelerations that human can feel.

  15. A multi-platform evaluation of the randomized CX low-rank matrix factorization in Spark

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

    Gittens, Alex; Kottalam, Jey; Yang, Jiyan

    We investigate the performance and scalability of the randomized CX low-rank matrix factorization and demonstrate its applicability through the analysis of a 1TB mass spectrometry imaging (MSI) dataset, using Apache Spark on an Amazon EC2 cluster, a Cray XC40 system, and an experimental Cray cluster. We implemented this factorization both as a parallelized C implementation with hand-tuned optimizations and in Scala using the Apache Spark high-level cluster computing framework. We obtained consistent performance across the three platforms: using Spark we were able to process the 1TB size dataset in under 30 minutes with 960 cores on all systems, with themore » fastest times obtained on the experimental Cray cluster. In comparison, the C implementation was 21X faster on the Amazon EC2 system, due to careful cache optimizations, bandwidth-friendly access of matrices and vector computation using SIMD units. We report these results and their implications on the hardware and software issues arising in supporting data-centric workloads in parallel and distributed environments.« less

  16. Human factors evaluation of teletherapy: Function and task analysis. Volume 2

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

    Kaye, R.D.; Henriksen, K.; Jones, R.

    1995-07-01

    As a treatment methodology, teletherapy selectively destroys cancerous and other tissue by exposure to an external beam of ionizing radiation. Sources of radiation are either a radioactive isotope, typically Cobalt-60 (Co-60), or a linear accelerator. Records maintained by the NRC have identified instances of teletherapy misadministration where the delivered radiation dose has differed from the radiation prescription (e.g., instances where fractions were delivered to the wrong patient, to the wrong body part, or were too great or too little with respect to the defined treatment volume). Both human error and machine malfunction have led to misadministrations. Effective and safe treatmentmore » requires a concern for precision and consistency of human-human and human-machine interactions throughout the course of therapy. The present study is the first part of a series of human factors evaluations for identifying the root causes that lead to human error in the teletherapy environment. The human factors evaluations included: (1) a function and task analysis of teletherapy activities, (2) an evaluation of the human-system interfaces, (3) an evaluation of procedures used by teletherapy staff, (4) an evaluation of the training and qualifications of treatment staff (excluding the oncologists), (5) an evaluation of organizational practices and policies, and (6) an identification of problems and alternative approaches for NRC and industry attention. The present report addresses the function and task analysis of teletherapy activities and provides the foundation for the conduct of the subsequent evaluations. The report includes sections on background, methodology, a description of the function and task analysis, and use of the task analysis findings for the subsequent tasks. The function and task analysis data base also is included.« less

  17. Ecto-5′-Nucleotidase: A Candidate Virulence Factor in Streptococcus sanguinis Experimental Endocarditis

    PubMed Central

    Fan, Jingyuan; Zhang, Yongshu; Chuang-Smith, Olivia N.; Frank, Kristi L.; Guenther, Brian D.; Kern, Marissa; Schlievert, Patrick M.; Herzberg, Mark C.

    2012-01-01

    Streptococcus sanguinis is the most common cause of infective endocarditis (IE). Since the molecular basis of virulence of this oral commensal bacterium remains unclear, we searched the genome of S. sanguinis for previously unidentified virulence factors. We identified a cell surface ecto-5′-nucleotidase (Nt5e), as a candidate virulence factor. By colorimetric phosphate assay, we showed that S. sanguinis Nt5e can hydrolyze extracellular adenosine triphosphate to generate adenosine. Moreover, a nt5e deletion mutant showed significantly shorter lag time (P<0.05) to onset of platelet aggregation than the wild-type strain, without affecting platelet-bacterial adhesion in vitro (P = 0.98). In the absence of nt5e, S. sanguinis caused IE (4 d) in a rabbit model with significantly decreased mass of vegetations (P<0.01) and recovered bacterial loads (log10CFU, P = 0.01), suggesting that Nt5e contributes to the virulence of S. sanguinis in vivo. As a virulence factor, Nt5e may function by (i) hydrolyzing ATP, a pro-inflammatory molecule, and generating adenosine, an immunosuppressive molecule to inhibit phagocytic monocytes/macrophages associated with valvular vegetations. (ii) Nt5e-mediated inhibition of platelet aggregation could also delay presentation of platelet microbicidal proteins to infecting bacteria on heart valves. Both plausible Nt5e-dependent mechanisms would promote survival of infecting S. sanguinis. In conclusion, we now show for the first time that streptococcal Nt5e modulates S. sanguinis-induced platelet aggregation and may contribute to the virulence of streptococci in experimental IE. PMID:22685551

  18. Experimental investigation on the hydrodynamic performance of a wave energy converter

    NASA Astrophysics Data System (ADS)

    Zheng, Xiong-bo; Ma, Yong; Zhang, Liang; Jiang, Jin; Liu, Heng-xu

    2017-06-01

    Wave energy is an important type of marine renewable energy. A wave energy converter (WEC) moored with two floating bodies was developed in the present study. To analyze the dynamic performance of the WEC, an experimental device was designed and tested in a tank. The experiment focused on the factors which impact the motion and energy conversion performance of the WEC. Dynamic performance was evaluated by the relative displacements and velocities of the oscillator and carrier which served as the floating bodies of WEC. Four factors were tested, i.e. wave height, wave period, power take-off (PTO) damping, and mass ratio ( R M) of the oscillator and carrier. Experimental results show that these factors greatly affect the energy conversion performance, especially when the wave period matches R M and PTO damping. According to the results, we conclude that: (a) the maximization of the relative displacements and velocities leads to the maximization of the energy conversion efficiency; (b) the larger the wave height, the higher the energy conversion efficiency will be; (c) the relationships of energy conversion efficiency with wave period, PTO damping, and R M are nonlinear, but the maximum efficiency is obtained when these three factors are optimally matched. Experimental results demonstrated that the energy conversion efficiency reached the peak at 28.62% when the wave height was 120 mm, wave period was 1.0 s, R M was 0.21, and the PTO damping was corresponding to the resistance of 100 Ω.

  19. Multi-Level Experimental and Analytical Evaluation of Two Composite Energy Absorbers

    NASA Technical Reports Server (NTRS)

    Jackson, Karen E.; Littell, Justin D.; Fasanella, Edwin L.; Annett, Martin S.; Seal, Michael D., II

    2015-01-01

    Two composite energy absorbers were developed and evaluated at NASA Langley Research Center through multi-level testing and simulation performed under the Transport Rotorcraft Airframe Crash Testbed (TRACT) research program. A conical-shaped energy absorber, designated the conusoid, was evaluated that consisted of four layers of hybrid carbon-Kevlar plain weave fabric oriented at [+45 deg/-45 deg/-45 deg/+45 deg] with respect to the vertical, or crush, direction. A sinusoidal-shaped energy absorber, designated the sinusoid, was developed that consisted of hybrid carbon-Kevlar plain weave fabric face sheets, two layers for each face sheet oriented at +/-45deg with respect to the vertical direction and a closed-cell ELFOAM P200 polyisocyanurate (2.0-lb/cu ft) foam core. The design goal for the energy absorbers was to achieve average floor-level accelerations of between 25- and 40-g during the full-scale crash test of a retrofitted CH-46E helicopter airframe, designated TRACT 2. Variations in both designs were assessed through dynamic crush testing of component specimens. Once the designs were finalized, subfloor beams of each configuration were fabricated and retrofitted into a barrel section of a CH-46E helicopter. A vertical drop test of the barrel section was conducted onto concrete to evaluate the performance of the energy absorbers prior to retrofit into TRACT 2. The retrofitted airframe was crash tested under combined forward and vertical velocity conditions onto soil, which is characterized as a sand/clay mixture. Finite element models were developed of all test articles and simulations were performed using LS-DYNA, a commercial nonlinear explicit transient dynamic finite element code. Test-analysis results are presented for each energy absorber as comparisons of time-history responses, as well as predicted and experimental structural deformations and progressive damage under impact loading for each evaluation level.

  20. Usefulness of myocardial parametric imaging to evaluate myocardial viability in experimental and in clinical studies

    PubMed Central

    Korosoglou, G; Hansen, A; Bekeredjian, R; Filusch, A; Hardt, S; Wolf, D; Schellberg, D; Katus, H A; Kuecherer, H

    2006-01-01

    Objective To evaluate whether myocardial parametric imaging (MPI) is superior to visual assessment for the evaluation of myocardial viability. Methods and results Myocardial contrast echocardiography (MCE) was assessed in 11 pigs before, during, and after left anterior descending coronary artery occlusion and in 32 patients with ischaemic heart disease by using intravenous SonoVue administration. In experimental studies perfusion defect area assessment by MPI was compared with visually guided perfusion defect planimetry. Histological assessment of necrotic tissue was the standard reference. In clinical studies viability was assessed on a segmental level by (1) visual analysis of myocardial opacification; (2) quantitative estimation of myocardial blood flow in regions of interest; and (3) MPI. Functional recovery between three and six months after revascularisation was the standard reference. In experimental studies, compared with visually guided perfusion defect planimetry, planimetric assessment of infarct size by MPI correlated more significantly with histology (r2  =  0.92 versus r2  =  0.56) and had a lower intraobserver variability (4% v 15%, p < 0.05). In clinical studies, MPI had higher specificity (66% v 43%, p < 0.05) than visual MCE and good accuracy (81%) for viability detection. It was less time consuming (3.4 (1.6) v 9.2 (2.4) minutes per image, p < 0.05) than quantitative blood flow estimation by regions of interest and increased the agreement between observers interpreting myocardial perfusion (κ  =  0.87 v κ  =  0.75, p < 0.05). Conclusion MPI is useful for the evaluation of myocardial viability both in animals and in patients. It is less time consuming than quantification analysis by regions of interest and less observer dependent than visual analysis. Thus, strategies incorporating this technique may be valuable for the evaluation of myocardial viability in clinical routine. PMID:15939722

  1. Usefulness of myocardial parametric imaging to evaluate myocardial viability in experimental and in clinical studies.

    PubMed

    Korosoglou, G; Hansen, A; Bekeredjian, R; Filusch, A; Hardt, S; Wolf, D; Schellberg, D; Katus, H A; Kuecherer, H

    2006-03-01

    To evaluate whether myocardial parametric imaging (MPI) is superior to visual assessment for the evaluation of myocardial viability. Myocardial contrast echocardiography (MCE) was assessed in 11 pigs before, during, and after left anterior descending coronary artery occlusion and in 32 patients with ischaemic heart disease by using intravenous SonoVue administration. In experimental studies perfusion defect area assessment by MPI was compared with visually guided perfusion defect planimetry. Histological assessment of necrotic tissue was the standard reference. In clinical studies viability was assessed on a segmental level by (1) visual analysis of myocardial opacification; (2) quantitative estimation of myocardial blood flow in regions of interest; and (3) MPI. Functional recovery between three and six months after revascularisation was the standard reference. In experimental studies, compared with visually guided perfusion defect planimetry, planimetric assessment of infarct size by MPI correlated more significantly with histology (r2 = 0.92 versus r2 = 0.56) and had a lower intraobserver variability (4% v 15%, p < 0.05). In clinical studies, MPI had higher specificity (66% v 43%, p < 0.05) than visual MCE and good accuracy (81%) for viability detection. It was less time consuming (3.4 (1.6) v 9.2 (2.4) minutes per image, p < 0.05) than quantitative blood flow estimation by regions of interest and increased the agreement between observers interpreting myocardial perfusion (kappa = 0.87 v kappa = 0.75, p < 0.05). MPI is useful for the evaluation of myocardial viability both in animals and in patients. It is less time consuming than quantification analysis by regions of interest and less observer dependent than visual analysis. Thus, strategies incorporating this technique may be valuable for the evaluation of myocardial viability in clinical routine.

  2. TiO2 synthesized by microwave assisted solvothermal method: Experimental and theoretical evaluation

    NASA Astrophysics Data System (ADS)

    Moura, K. F.; Maul, J.; Albuquerque, A. R.; Casali, G. P.; Longo, E.; Keyson, D.; Souza, A. G.; Sambrano, J. R.; Santos, I. M. G.

    2014-02-01

    In this study, a microwave assisted solvothermal method was used to synthesize TiO2 with anatase structure. The synthesis was done using Ti (IV) isopropoxide and ethanol without templates or alkalinizing agents. Changes in structural features were observed with increasing time of synthesis and evaluated using periodic quantum chemical calculations. The anatase phase was obtained after only 1 min of reaction besides a small amount of brookite phase. Experimental Raman spectra are in accordance with the theoretical one. Micrometric spheres constituted by nanometric particles were obtained for synthesis from 1 to 30 min, while spheres and sticks were observed after 60 min.

  3. DSN human factors project

    NASA Technical Reports Server (NTRS)

    Chafin, R. L.; Martin, T. H.

    1980-01-01

    The project plan was to hold focus groups to identify the factors influencing the ease of use characteristics of software and to bond the problem. A questionnaire survey was conducted to evaluate those factors which were more appropriately measured with that method. The performance oriented factors were analyzed and relationships hypothesized. The hypotheses were put to test in the experimental phase of the project. In summary, the initial analysis indicates that there is an initial performance effect favoring computer controlled dialogue but the advantage fades fast as operators become experienced. The user documentation style is seen to have a significant effect on performance. The menu and prompt command formats are preferred by inexperienced operators. The short form mnemonic is least favored. There is no clear best command format but the short form mnemonic is clearly the worst.

  4. Measurement and evaluation practices of factors that contribute to effective health promotion collaboration functioning: A scoping review.

    PubMed

    Stolp, Sean; Bottorff, Joan L; Seaton, Cherisse L; Jones-Bricker, Margaret; Oliffe, John L; Johnson, Steven T; Errey, Sally; Medhurst, Kerensa; Lamont, Sonia

    2017-04-01

    The purpose of this scoping review was to identify promising factors that underpin effective health promotion collaborations, measurement approaches, and evaluation practices. Measurement approaches and evaluation practices employed in 14 English-language articles published between January 2001 and October 2015 were considered. Data extraction included research design, health focus of the collaboration, factors being evaluated, how factors were conceptualized and measured, and outcome measures. Studies were methodologically diverse employing either quantitative methods (n=9), mixed methods (n=4), or qualitative methods (n=1). In total, these 14 studies examined 113 factors, 88 of which were only measured once. Leadership was the most commonly studied factor but was conceptualized differently across studies. Six factors were significantly associated with outcome measures across studies; leadership (n=3), gender (n=2), trust (n=2), length of the collaboration (n=2), budget (n=2) and changes in organizational model (n=2). Since factors were often conceptualized differently, drawing conclusions about their impact on collaborative functioning remains difficult. The use of reliable and validated tools would strengthen evaluation of health promotion collaborations and would support and enhance the effectiveness of collaboration. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  5. The effects of profound hypothermia on pancreas ischemic injury: a new experimental model.

    PubMed

    Rocha-Santos, Vinicius; Ferro, Oscar Cavalcante; Pantanali, Carlos Andrés; Seixas, Marcel Povlovistsch; Pecora, Rafael Antonio Arruda; Pinheiro, Rafael Soares; Claro, Laura Carolina López; Abdo, Emílio Elias; Chaib, Eleazar; D'Albuquerque, Luiz Augusto Carneiro

    2014-08-01

    Pancreatic ischemia-reperfusion (IR) has a key role in pancreas surgery and transplantation. Most experimental models evaluate the normothermic phase of the IR. We proposed a hypothermic model of pancreas IR to evaluate the benefic effects of the cold ischemic phase. We performed a reproducible model of hypothermic pancreatic IR. The ischemia was induced in the pancreatic tail portion (1-hour ischemia, 4-hour reperfusion) in 36 Wistar rats. They are divided in 3 groups as follows: group 1 (control), sham; group 2, normothermic IR; and group 3, hypothermic IR. In group 3, the temperature was maintained as close to 4.5°C. After reperfusion, serum amylase and lipase levels, inflammatory mediators (tumor necrosis factor α, interleukin 6), and pancreas histology were evaluated. In pancreatic IR groups, amylase, cytokines, and histological damage were significantly increased when compared with group 1. In the group 3, we observed a significant decrease in tumor necrosis factor α (P = 0.004) and interleukin 6 (P = 0.001) when compared with group 2. We did not observe significant difference in amylase (P = 0.867), lipase (P = 0.993), and histology (P = 0.201). In our experimental model, we reproduced the cold phase of pancreas IR, and the pancreas hypothermia reduced the inflammatory mediators after reperfusion.

  6. An experimental evaluation of drug-induced mutational meltdown as an antiviral treatment strategy.

    PubMed

    Bank, Claudia; Renzette, Nicholas; Liu, Ping; Matuszewski, Sebastian; Shim, Hyunjin; Foll, Matthieu; Bolon, Daniel N A; Zeldovich, Konstantin B; Kowalik, Timothy F; Finberg, Robert W; Wang, Jennifer P; Jensen, Jeffrey D

    2016-11-01

    The rapid evolution of drug resistance remains a critical public health concern. The treatment of influenza A virus (IAV) has proven particularly challenging, due to the ability of the virus to develop resistance against current antivirals and vaccines. Here, we evaluate a novel antiviral drug therapy, favipiravir, for which the mechanism of action in IAV involves an interaction with the viral RNA-dependent RNA polymerase resulting in an effective increase in the viral mutation rate. We used an experimental evolution framework, combined with novel population genetic method development for inference from time-sampled data, to evaluate the effectiveness of favipiravir against IAV. Evaluating whole genome polymorphism data across 15 time points under multiple drug concentrations and in controls, we present the first evidence for the ability of IAV populations to effectively adapt to low concentrations of favipiravir. In contrast, under high concentrations, we observe population extinction, indicative of mutational meltdown. We discuss the observed dynamics with respect to the evolutionary forces at play and emphasize the utility of evolutionary theory to inform drug development. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  7. Non-auditory factors affecting urban soundscape evaluation.

    PubMed

    Jeon, Jin Yong; Lee, Pyoung Jik; Hong, Joo Young; Cabrera, Densil

    2011-12-01

    The aim of this study is to characterize urban spaces, which combine landscape, acoustics, and lighting, and to investigate people's perceptions of urban soundscapes through quantitative and qualitative analyses. A general questionnaire survey and soundwalk were performed to investigate soundscape perception in urban spaces. Non-auditory factors (visual image, day lighting, and olfactory perceptions), as well as acoustic comfort, were selected as the main contexts that affect soundscape perception, and context preferences and overall impressions were evaluated using an 11-point numerical scale. For qualitative analysis, a semantic differential test was performed in the form of a social survey, and subjects were also asked to describe their impressions during a soundwalk. The results showed that urban soundscapes can be characterized by soundmarks, and soundscape perceptions are dominated by acoustic comfort, visual images, and day lighting, whereas reverberance in urban spaces does not yield consistent preference judgments. It is posited that the subjective evaluation of reverberance can be replaced by physical measurements. The categories extracted from the qualitative analysis revealed that spatial impressions such as openness and density emerged as some of the contexts of soundscape perception. © 2011 Acoustical Society of America

  8. Evaluation of risk factors for perforated peptic ulcer.

    PubMed

    Yamamoto, Kazuki; Takahashi, Osamu; Arioka, Hiroko; Kobayashi, Daiki

    2018-02-15

    The aim of this study was to evaluate the prediction factors for perforated peptic ulcer (PPU). At St. Luke's International Hospital in Tokyo, Japan, a case control study was performed between August 2004 and March 2016. All patients diagnosed with PPU were included. As control subjects, patients with age, sex and date of CT scan corresponding to those of the PPU subjects were included in the study at a proportion of 2 controls for every PPU subject. All data such as past medical histories, physical findings, and laboratory data were collected through chart reviews. Univariate analyses and multivariate analyses with logistic regression were conducted, and receiver operating characteristic curves (ROCs) were calculated to show validity. Sensitivity analyses were performed to confirm results using a stepwise method and conditional logistic regression. A total of 408 patients were included in this study; 136 were a group of patients with PPU, and 272 were a control group. Univariate analysis showed statistical significance in many categories. Four different models of multivariate analyses were conducted, and significant differences were found for muscular defense and a history of peptic ulcer disease (PUD) in all models. The conditional forced-entry analysis of muscular defense showed an odds ratio (OR) of 23.8 (95% confidence interval [CI]: 5.70-100.0), and the analysis of PUD history showed an OR of 6.40 (95% CI: 1.13-36.2). The sensitivity analysis showed consistent results, with an OR of 23.8-366.2 for muscular defense and an OR of 3.67-7.81 for PUD history. The area under the curve (AUC) of all models was high enough to confirm the results. However, anticoagulants, known risk factors for PUD, did not increase the risk for PPU in our study. The conditional forced-entry analysis of anticoagulant use showed an OR of 0.85 (95% CI: 0.03-22.3). The evaluation of prediction factors and development of a prediction rule for PPU may help our decision making in performing a

  9. Evaluating Effective Teaching in College Level Economics Using Student Ratings of Instruction: A Factor Analytic Approach

    ERIC Educational Resources Information Center

    Agbetsiafa, Douglas

    2010-01-01

    This paper explores the factors that affect students' evaluation of economic instruction using a sample of 1300 completed rating instruments at a comprehensive four-year mid-western public university. The study uses factor analysis to determine the validity and reliability of the evaluation instrument in assessing instructor or course…

  10. Experimental Evaluation of a Water Shield for a Surface Power Reactor

    NASA Technical Reports Server (NTRS)

    Pearson, J. Boise; Reid, Robert S.

    2006-01-01

    As part of the Vision for Space Exploration the end of the next decade will bring man back to the surface of the moon. One of the most critical issues for the establishment of human presence on the moon will be the availability of compact power sources. The establishment of man on the moon will require power from greater than 10's of kWt's in follow on years. Nuclear reactors are extremely we11 suited to meet the needs for power generation on the lunar or Martian surface. reactor system. Several competing concepts exist for lightweight, safe, robust shielding systems such as a water shield, lithium hydride (LiH), Boron Carbide, and others. Water offers several potential advantages, including reduced cost, reduced technical risk, and reduced mass. Water has not typically been considered for space reactor applications because of the need for gravity to remove the potential for radiation streaming paths. The water shield concept relies on predictions of passive circulation of the shield water by natural convection to adequately cool the shield. This prediction needs to be experimentally evaluated, especially for shields with complex geometries. MSFC has developed the experience and fac necessary to do this evaluation in the Early Flight Fission - Test Facility (EFF-TF).

  11. Evaluating Academic Journals Using Impact Factor and Local Citation Score

    ERIC Educational Resources Information Center

    Chung, Hye-Kyung

    2007-01-01

    This study presents a method for journal collection evaluation using citation analysis. Cost-per-use (CPU) for each title is used to measure cost-effectiveness with higher CPU scores indicating cost-effective titles. Use data are based on the impact factor and locally collected citation score of each title and is compared to the cost of managing…

  12. Experimental Evaluation of the Value Added by Raising a Reader and Supplemental Parent Training in Shared Reading

    ERIC Educational Resources Information Center

    Anthony, Jason L.; Williams, Jeffrey M.; Zhang, Zhoe; Landry, Susan H.; Dunkelberger, Martha J.

    2014-01-01

    Research Findings: In an effort toward developing a comprehensive, effective, scalable, and sustainable early childhood education program for at-risk populations, we conducted an experimental evaluation of the value added by 2 family involvement programs to the Texas Early Education Model (TEEM). A total of 91 preschool classrooms that served…

  13. Children's Feedback Preferences in Response to an Experimentally Manipulated Peer Evaluation Outcome: The Role of Depressive Symptoms

    ERIC Educational Resources Information Center

    Reijntjes, Albert; Dekovic, Maja; Vermande, Marjolijn; Telch, Michael J.

    2007-01-01

    The present study examined the linkage between pre-adolescent children's depressive symptoms and their preferences for receiving positive vs. negative feedback subsequent to being faced with an experimentally manipulated peer evaluation outcome in real time. Participants (n = 142) ages 10 to 13, played a computer contest based on the television…

  14. Evaluation of damping loss factor of flat laminates by sound transmission

    NASA Astrophysics Data System (ADS)

    Parrinello, A.; Ghiringhelli, G. L.

    2018-06-01

    A novel approach to investigate and evaluate the damping loss factor of a planar multilayered structure is presented. A statistical analysis reveals the connection between the damping properties of the structure and the transmission of sound through the thickness of its laterally infinite counterpart. The obtained expression for the panel loss factor involves all the derivatives of the transmission and reflection coefficients of the layered structure with respect each layer damping. The properties of the fluid for which the sound transmission is evaluated are chosen to fulfil the hypotheses on the basis of the statistical formulation. A transfer matrix approach is used to compute the required transmission and reflection coefficients, making it possible to deal with structures having arbitrary stratifications of different layers and also granting high efficiency in a wide frequency range. Comparison with alternative formulations and measurements demonstrates the effectiveness of the proposed methodology.

  15. Evaluation and experimentation with duck management strategies

    USGS Publications Warehouse

    Nichols, J.D.; Johnson, F.A.

    1989-01-01

    Our knowledge of the effects of hunting regulations on duck populations has been based largely on retrospective studies of historical data. We have reached the limits of what can be learned in this way. Future knowledge gains will likely come about only through experimentation and adaptive management.

  16. The experimental identification of magnetorheological dampers and evaluation of their controllers

    NASA Astrophysics Data System (ADS)

    Metered, H.; Bonello, P.; Oyadiji, S. O.

    2010-05-01

    Magnetorheological (MR) fluid dampers are semi-active control devices that have been applied over a wide range of practical vibration control applications. This paper concerns the experimental identification of the dynamic behaviour of an MR damper and the use of the identified parameters in the control of such a damper. Feed-forward and recurrent neural networks are used to model both the direct and inverse dynamics of the damper. Training and validation of the proposed neural networks are achieved by using the data generated through dynamic tests with the damper mounted on a tensile testing machine. The validation test results clearly show that the proposed neural networks can reliably represent both the direct and inverse dynamic behaviours of an MR damper. The effect of the cylinder's surface temperature on both the direct and inverse dynamics of the damper is studied, and the neural network model is shown to be reasonably robust against significant temperature variation. The inverse recurrent neural network model is introduced as a damper controller and experimentally evaluated against alternative controllers proposed in the literature. The results reveal that the neural-based damper controller offers superior damper control. This observation and the added advantages of low-power requirement, extended service life of the damper and the minimal use of sensors, indicate that a neural-based damper controller potentially offers the most cost-effective vibration control solution among the controllers investigated.

  17. Milk-derived or recombinant transforming growth factor-beta has effects on immunological outcomes: a review of evidence from animal experimental studies.

    PubMed

    Oddy, W H; McMahon, R J

    2011-06-01

    Identified factors from milk have been shown to improve health outcomes. One specific factor, transforming growth factor-Beta (TGF)-β, has been identified previously as having the potential to impact on immunological outcomes in the newborn offspring. The primary objective of this review was to examine the published studies that have considered TGF-β in association with immunological outcomes of experimental models. We hypothesized that oral administration of TGF-β (through human milk, cow's milk, infant formula) or recombinant TGF-β delivered via gavage, may down-regulate immune activation in newborn offspring. Animal experimental studies were identified through MEDLINE, CAB Abstracts, Biological Abstracts and Scopus. Selection criteria included well-described animal populations, sample and study design, source of TGF-β, age and immunological outcomes measured and effect size. The findings were summarized temporally in tabular format, giving an overall measure of effect based on the literature available since 1994. Animal experimental studies (n=13) were included in the review to determine an association between maternal TGF-β and immunological outcomes. Overall 92% of these studies (12/13) showed a positive association with TGF-β1 or TGF-β2, demonstrating protection against immunologically related outcomes in early life in an animal model. TGF-β is important in developing and maintaining appropriate immune responses in the offspring. TGF-β delivered orally to neonatal animals provides protection against adverse immunological outcomes, corroborating and supporting findings from human studies. Animal studies provide important clues to the pathogenesis and therapeutics of immune activation and allergy in early childhood. TGF-βs are important growth factors involved in maintaining homeostasis in the intestine, regulating inflammation and allergy development and promoting oral tolerance in infants. Thus, taken as a whole, these and our other findings

  18. Capstone 3 electronic flight bag (EFB) - airport moving map operational evaluation : human factors report

    DOT National Transportation Integrated Search

    2013-05-30

    This report documents the human factors activities conducted as part of the Capstone 3 Electronic Flight Bag (EFB) Airport Moving Map operational evaluation. The purpose of that operational evaluation was to understand the safety implications of ...

  19. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis

    PubMed Central

    Camacho, Ana María; Veganzones, Mariano; Claver, Juan; Martín, Francisco; Sevilla, Lorenzo; Sebastián, Miguel Ángel

    2016-01-01

    Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE) simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS2 grease, silicone oil, and copper paste) to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs). The results show that for small reductions (rh < 20%), the conventional RCT can be applied because the tribological conditions remain similar. For large reductions (rh > 20%), it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered. PMID:28773868

  20. Determination of Actual Friction Factors in Metal Forming under Heavy Loaded Regimes Combining Experimental and Numerical Analysis.

    PubMed

    Camacho, Ana María; Veganzones, Mariano; Claver, Juan; Martín, Francisco; Sevilla, Lorenzo; Sebastián, Miguel Ángel

    2016-09-01

    Tribological conditions can change drastically during heavy loaded regimes as experienced in metal forming; this is especially critical when lubrication can only be applied at the early stage of the process because the homogeneous lubricant layer can break along the die-workpiece interface. In these cases, adopting a constant friction factor for the lubricant-surface pair may not be a valid assumption. This paper presents a procedure based on the use of dual friction factor maps to determine friction factors employed in heavy loaded regimes. A finite element (FE) simulation is used to obtain the friction factor map for the alloy UNS A96082. Experiments were conducted using four lubricants (aluminum anti-size, MoS₂ grease, silicone oil, and copper paste) to determine the actual friction curves. The experimental procedure is based on the application of lubricant only at the beginning of the first stage of ring compression, and not at intermediate stages as is usual in typical ring compression tests (RCTs). The results show that for small reductions ( r h < 20%), the conventional RCT can be applied because the tribological conditions remain similar. For large reductions ( r h > 20%), it is recommended to obtain an average value of the friction factor for every lubricant-surface pair in the range of deformation considered.

  1. 10 CFR 100.10 - Factors to be considered when evaluating sites.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Section 100.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) REACTOR SITE CRITERIA Evaluation Factors for Stationary Power Reactor Site Applications Before January 10, 1997 and for Testing Reactors § 100... include those relating both to the proposed reactor design and the characteristics peculiar to the site...

  2. 10 CFR 100.10 - Factors to be considered when evaluating sites.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Section 100.10 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) REACTOR SITE CRITERIA Evaluation Factors for Stationary Power Reactor Site Applications Before January 10, 1997 and for Testing Reactors § 100... include those relating both to the proposed reactor design and the characteristics peculiar to the site...

  3. Application of Experimental and Quasi-Experimental Research Designs to Educational Software Evaluation.

    ERIC Educational Resources Information Center

    Muller, Eugene W.

    1985-01-01

    Develops generalizations for empirical evaluation of software based upon suitability of several research designs--pretest posttest control group, single-group pretest posttest, nonequivalent control group, time series, and regression discontinuity--to type of software being evaluated, and on circumstances under which evaluation is conducted. (MBR)

  4. Computed Tomography Angiography Evaluation of Risk Factors for Unstable Intracranial Aneurysms.

    PubMed

    Wang, Guang-Xian; Gong, Ming-Fu; Wen, Li; Liu, Lan-Lan; Yin, Jin-Bo; Duan, Chun-Mei; Zhang, Dong

    2018-03-19

    To evaluate risk factors for instability in intracranial aneurysms (IAs) using computed tomography angiography (CTA). A total of 614 consecutive patients diagnosed with 661 IAs between August 2011 and February 2016 were reviewed. Patients and IAs were divided into stable and unstable groups. Along with clinical characteristics, IA characteristics were evaluated by CTA. Multiple logistic regression analysis was used to identify the independent risk factors associated with unstable IAs. Receiver operating characteristic (ROC) curve analysis was performed on the final model, and optimal thresholds were obtained. Patient age (odds ratio [OR], 0.946), cerebral atherosclerosis (CA; OR, 0.525), and IAs located at the middle cerebral artery (OR, 0.473) or internal carotid artery (OR, 0.512) were negatively correlated with instability, whereas IAs with irregular shape (OR, 2.157), deep depth (OR, 1.557), or large flow angle (FA; OR, 1.015) were more likely to be unstable. ROC analysis revealed threshold values of age, depth, and FA of 59.5 years, 4.25 mm, and 87.8°, respectively. The stability of IAs is significantly affected by several factors, including patient age and the presence of CA. IA shape and location also have an impact on the stability of IAs. Growth into an irregular shape, with a deep depth, and a large FA are risk factors for a change in IAs from stable to unstable. Copyright © 2018 Elsevier Inc. All rights reserved.

  5. Experimental analysis of multiple factors on hydraulic fracturing in coalbed methane reservoirs

    PubMed Central

    Ma, Geng; Liu, Xiao; Tao, Yunqi; Feng, Dan; Li, Rui

    2018-01-01

    Hydraulic fracturing can improve the permeability of coalbed methane (CBM) reservoirs effectively, which is of great significance to the commercial production of CBM. However, the efficiency of hydraulic fracturing is affected by multiple factors. The mechanism of fracture initiation, morphology and propagation in CBM reservoirs is not clear and need to be further explored. Hydraulic fracturing experiment is an accurate tool to explore these mechanisms. The quantity of experimental coal rock is large and processing method is complex, so specimen made of similar materials was applied to replace coal rock. The true triaxial hydraulic fracturing experimental apparatus, 3D scanning device for coal rock section were applied to carry out hydraulic fracturing experiment. The results show that the initiation pressure is inversely proportional to the horizontal stress difference (Δσ) and positively related to fracturing fluid injection rate. When vertical stress (σv) is constant, the initiation pressure and fracture width decrease with the increasing of Δσ. Natural fractures can be connected by main fracture when propagates perpendicular to the direction of minimum horizontal stress (σh), then secondary fractures and fracture network form in CBM reservoirs. When two stresses of crustal stress are close and far different from the third one, the fracture morphology and propagation become complex. Influenced by perforations and filtration of fracturing fluid in specimen, fracturing fluid flows to downward easily after comparing horizontal well fracturing with vertical well fracturing. Fracture width increases with the decreasing of elastic modulus, the intensity of fracture is positively related with the elastic modulus of coal rock. The research results can provide theoretical basis and technical support for the efficient development of CBM. PMID:29621295

  6. Experimental analysis of multiple factors on hydraulic fracturing in coalbed methane reservoirs.

    PubMed

    Zhang, Fan; Ma, Geng; Liu, Xiao; Tao, Yunqi; Feng, Dan; Li, Rui

    2018-01-01

    Hydraulic fracturing can improve the permeability of coalbed methane (CBM) reservoirs effectively, which is of great significance to the commercial production of CBM. However, the efficiency of hydraulic fracturing is affected by multiple factors. The mechanism of fracture initiation, morphology and propagation in CBM reservoirs is not clear and need to be further explored. Hydraulic fracturing experiment is an accurate tool to explore these mechanisms. The quantity of experimental coal rock is large and processing method is complex, so specimen made of similar materials was applied to replace coal rock. The true triaxial hydraulic fracturing experimental apparatus, 3D scanning device for coal rock section were applied to carry out hydraulic fracturing experiment. The results show that the initiation pressure is inversely proportional to the horizontal stress difference (Δσ) and positively related to fracturing fluid injection rate. When vertical stress (σv) is constant, the initiation pressure and fracture width decrease with the increasing of Δσ. Natural fractures can be connected by main fracture when propagates perpendicular to the direction of minimum horizontal stress (σh), then secondary fractures and fracture network form in CBM reservoirs. When two stresses of crustal stress are close and far different from the third one, the fracture morphology and propagation become complex. Influenced by perforations and filtration of fracturing fluid in specimen, fracturing fluid flows to downward easily after comparing horizontal well fracturing with vertical well fracturing. Fracture width increases with the decreasing of elastic modulus, the intensity of fracture is positively related with the elastic modulus of coal rock. The research results can provide theoretical basis and technical support for the efficient development of CBM.

  7. Empirical evaluation of humpback whale telomere length estimates; quality control and factors causing variability in the singleplex and multiplex qPCR methods.

    PubMed

    Olsen, Morten Tange; Bérubé, Martine; Robbins, Jooke; Palsbøll, Per J

    2012-09-06

    Telomeres, the protective cap of chromosomes, have emerged as powerful markers of biological age and life history in model and non-model species. The qPCR method for telomere length estimation is one of the most common methods for telomere length estimation, but has received recent critique for being too error-prone and yielding unreliable results. This critique coincides with an increasing awareness of the potentials and limitations of the qPCR technique in general and the proposal of a general set of guidelines (MIQE) for standardization of experimental, analytical, and reporting steps of qPCR. In order to evaluate the utility of the qPCR method for telomere length estimation in non-model species, we carried out four different qPCR assays directed at humpback whale telomeres, and subsequently performed a rigorous quality control to evaluate the performance of each assay. Performance differed substantially among assays and only one assay was found useful for telomere length estimation in humpback whales. The most notable factors causing these inter-assay differences were primer design and choice of using singleplex or multiplex assays. Inferred amplification efficiencies differed by up to 40% depending on assay and quantification method, however this variation only affected telomere length estimates in the worst performing assays. Our results suggest that seemingly well performing qPCR assays may contain biases that will only be detected by extensive quality control. Moreover, we show that the qPCR method for telomere length estimation can be highly precise and accurate, and thus suitable for telomere measurement in non-model species, if effort is devoted to optimization at all experimental and analytical steps. We conclude by highlighting a set of quality controls which may serve for further standardization of the qPCR method for telomere length estimation, and discuss some of the factors that may cause variation in qPCR experiments.

  8. Evaluation of procoagulant tissue factor expression in canine hemangiosarcoma cell lines

    PubMed Central

    Witter, Lauren E.; Gruber, Erika J.; Lean, Fabian Z. X.; Stokol, Tracy

    2017-01-01

    OBJECTIVE To evaluate expression of procoagulant tissue factor (TF) by canine hemangiosarcoma cells in vitro. SAMPLES 4 canine hemangiosarcoma cell lines (SB-HSA [mouse-passaged cutaneous tumor], Emma [primary metastatic brain tumor], and Frog and Dal-1 [primary splenic tumors]) and 1 nonneoplastic canine endothelial cell line (CnAoEC). PROCEDURES TF mRNA and TF antigen expression were evaluated by quantitative real-time PCR assay and flow cytometry, respectively. Thrombin generation was measured in canine plasma and in coagulation factor–replete or specific coagulation factor–deficient human plasma by calibrated automated thrombography. Corn trypsin inhibitor and annexin V were used to examine contributions of contact activation and membrane-bound phosphatidylserine, respectively, to thrombin generation. RESULTS All cell lines expressed TF mRNA and antigen, with significantly greater expression of both products in SB-HSA and Emma cells than in CnAoEC. A greater percentage of SB-HSA cells expressed TF antigen, compared with other hemangiosarcoma cell lines. All hemangiosarcoma cell lines generated significantly more thrombin than did CnAoEC in canine or factor-replete human plasma. Thrombin generation induced by SB-HSA cells was significantly lower in factor VII-deficient plasma than in factor-replete plasma and was abolished in factor X–deficient plasma; residual thrombin generation in FVII-deficient plasma was abolished by incubation of cells with annexin V. Thrombin generation by SB-HSA cells was unaffected by the addition of corn trypsin inhibitor. CONCLUSIONS AND CLINICAL RELEVANCE Hemangiosarcoma cell lines expressed procoagulant TF in vitro. Further research is needed to determine whether TF can be used as a biomarker for hemostatic dysfunction in dogs with hemangiosarcoma. PMID:28029283

  9. Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology

    PubMed Central

    Dong, Jia; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K.N.; Knobeloch, Daniel; Gerlach, Jörg C.; Zeilinger, Katrin

    2008-01-01

    Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes. PMID:19003182

  10. Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology.

    PubMed

    Dong, Jia; Mandenius, Carl-Fredrik; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K N; Knobeloch, Daniel; Gerlach, Jörg C; Zeilinger, Katrin

    2008-07-01

    Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes.

  11. Effects of tumor necrosis factor alpha antagonist, platelet activating factor antagonist, and nitric oxide synthase inhibitor on experimental otitis media with effusion.

    PubMed

    Kim, Dong-Hyun; Park, Yong-Soo; Jeon, Eun-Ju; Yeo, Sang-Won; Chang, Ki-Hong; Lee, Seung Kyun

    2006-08-01

    We studied the inflammatory responses in otitis media with effusion induced by lipopolysaccharide (LPS) in rats, and compared the preventive effects of tumor necrosis factor (TNF) soluble receptor type I (sTNFRI, a TNF-alpha antagonist), platelet activating factor antagonist, and the nitric oxide synthase inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME). We used 2 control groups of Sprague Dawley rats (untreated and saline-treated) and 4 experimental groups, which all received an intratympanic injection of LPS, followed in 3 groups by experimental treatment of the same ear. The LPS group had no additional treatment. The L-NAME group received intraperitoneal injection of L-NAME and was reinjected after 12 hours. The A-85783 group was first given an intraperitoneal injection of A-85783. The sTNFRI group was first given an intratympanic injection of sTNFRI. Twenty-four hours after the initial intratympanic injection of LPS, temporal bones from each group were examined histopathologically and the vascular permeability of the middle ear mucosa was measured by Evans blue vital dye staining. The L-NAME, A-85783, and sTNFRI groups showed significantly reduced capillary permeability, subepithelial edema, and infiltration of inflammatory cells in comparison with the LPS group. There were no differences in capillary permeability, subepithelial edema, or infiltration of inflammatory cells between the A-85783 and sTNFRI groups. The L-NAME group showed no difference in vascular permeability or subepithelial edema in comparison with the A-85783 and sTNFRI groups, but showed more infiltration of inflammatory cells. We conclude that sTNFRI, A-85783, and L-NAME can be proposed as alternative future treatments for otitis media with effusion. However, L-NAME may be the least effective of these agents.

  12. Evaluation of factors that affect hip moment impulse during gait: A systematic review.

    PubMed

    Inai, Takuma; Takabayashi, Tomoya; Edama, Mutsuaki; Kubo, Masayoshi

    2018-03-01

    Decreasing the daily cumulative hip moments in the frontal and sagittal planes may lower the risk of hip osteoarthritis. Therefore, it may be important to evaluate factors that affect hip moment impulse during gait. It is unclear what factors affect hip moment impulse during gait. This systematic review aimed to evaluate different factors that affect hip moment impulse during gait in healthy adults and patients with hip osteoarthritis. Four databases (Scopus, ScienceDirect, PubMed, and PEDro) were searched up to August 2017 to identify studies that examined hip moment impulse during gait. Data extracted for analysis included the sample size, age, height, body mass, type of intervention, and main findings. After screening, 10 of the 975 studies identified were included in our analysis. Several factors, including a rocker bottom shoe, FitFlop™ sandals, ankle push-off, posture, stride length, body-weight unloading, a rollator, walking poles, and a knee brace, were reviewed. The main findings were as follows: increasing ankle push-off decreased both the hip flexion and extension moment impulses; body-weight unloading decreased both the hip extension and adduction moment impulses; the FitFlop™ sandal increased the sum of the hip flexion and extension moment impulses; long strides increased the hip extension moment impulse; and the use of a knee brace increased hip flexion moment impulse. Of note, none of the eligible studies included patients with hip osteoarthritis. The hip moment impulses can be modified by person-specific factors (ankle push-off and long strides) and external factors (body-weight unloading and use of the FitFlop™ sandals and a knee brace). Effects on the progression of hip osteoarthritis remain to be evaluated. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. A quasi-experimental evaluation of a community-based HIV prevention intervention for Mexican American female adolescents: the SHERO's program.

    PubMed

    Harper, Gary W; Bangi, Audrey K; Sanchez, Bernadette; Doll, Mimi; Pedraza, Ana

    2009-10-01

    This article describes a quasi-experimental evaluation of a community-based, culturally and ecologically tailored HIV prevention intervention for Mexican American female adolescents grounded in the AIDS risk reduction model. A total of 378 Mexican American female adolescents (mean age = 15.2) participated in either the nine-session SHERO's (a female-gendered version of the word hero) intervention or a single session information-only HIV prevention intervention. Assessment data were collected at pretest, posttest, and 2-month follow up. Significant improvements across all time points were revealed on measures of self-esteem, condom attitudes, beliefs regarding a woman's control of her sexuality, beliefs regarding sexual assault, perceived peer norms, and HIV/AIDS and STI knowledge. At posttest SHERO's participants were more likely to carry condoms and to report abstaining from vaginal sex in the previous 2 months; and at 2-month follow up they reported using condoms more often in the preceding 2 months and planned on using them more frequently in the coming 2 months. Findings support the development of community-based adolescent HIV prevention interventions that address culturally specific ecological factors.

  14. Numerical and Experimental Evaluation of Blast Retrofit of Windows

    DTIC Science & Technology

    2013-07-18

    Retrofitting windows against blast load environments is a topic under considerable investigation. The retrofits added to existing buildings need the strength...experimentally survived the desired loading environment. Two views of the posttest vertical blind system can be seen in Figure 8. Although the vertical...vertica Figure 8: Posttest views l blind system and the connections Both the numerical and experimental systems deformed in a similar

  15. Myocardin-related transcription factors and SRF are required for cytoskeletal dynamics and experimental metastasis.

    PubMed

    Medjkane, Souhila; Perez-Sanchez, Cristina; Gaggioli, Cedric; Sahai, Erik; Treisman, Richard

    2009-03-01

    Rho GTPases control cytoskeletal dynamics through cytoplasmic effectors and regulate transcriptional activation through myocardin-related transcription factors (MRTFs), which are co-activators for serum response factor (SRF). We used RNA interference to investigate the contribution of the MRTF-SRF pathway to cytoskeletal dynamics in MDA-MB-231 breast carcinoma and B16F2 melanoma cells, in which basal MRTF-SRF activity is Rho-dependent. Depletion of MRTFs or SRF reduced cell adhesion, spreading, invasion and motility in culture, without affecting proliferation or inducing apoptosis. MRTF-depleted tumour cell xenografts showed reduced cell motility but proliferated normally. Tumour cells depleted of MRTF or SRF failed to colonize the lung from the bloodstream, being unable to persist after their arrival in the lung. Only a few genes show MRTF-dependent expression in both cell lines. Two of these, MYH9 (NMHCIIa) and MYL9 (MLC2), are also required for invasion and lung colonization. Conversely, expression of activated MAL/MRTF-A increases lung colonization by poorly metastatic B16F0 cells. Actin-based cell behaviour and experimental metastasis thus require Rho-dependent nuclear signalling through the MRTF-SRF network.

  16. Evaluation of Amyloid Protective Factors and Alzheimer Disease Neurodegeneration Protective Factors in Elderly Individuals.

    PubMed

    Vemuri, Prashanthi; Knopman, David S; Lesnick, Timothy G; Przybelski, Scott A; Mielke, Michelle M; Graff-Radford, Jonathan; Murray, Melissa E; Roberts, Rosebud O; Vassilaki, Maria; Lowe, Val J; Machulda, Mary M; Jones, David T; Petersen, Ronald C; Jack, Clifford R

    2017-06-01

    While amyloid and neurodegeneration are viewed together as Alzheimer disease pathophysiology (ADP), the factors that influence amyloid and AD-pattern neurodegeneration may be considerably different. Protection from these ADP factors may be important for aging without significant ADP. To identify the combined and independent protective factors for amyloid and AD-pattern neurodegeneration in a population-based sample and to test the hypothesis that "exceptional agers" with advanced ages do not have significant ADP because they have protective factors for amyloid and neurodegeneration. This cohort study conducted a prospective analysis of 942 elderly individuals (70-≥90 years) with magnetic resonance imaging and Pittsburgh compound B-positron emission tomography scans enrolled in the Mayo Clinic Study of Aging, a longitudinal population-based study of cognitive aging in Olmsted County, Minnesota. We operationalized "exceptional aging" without ADP by considering individuals 85 years or older to be without significant evidence of ADP. We evaluated predictors including demographics, APOE, intellectual enrichment, midlife risk factors (physical inactivity, obesity, smoking, diabetes, hypertension, and dyslipidemia), and the total number of late-life cardiac and metabolic conditions. We used multivariate linear regression models to identify the combined and independent protective factors for amyloid and AD-pattern neurodegeneration. Using a subsample of the cohort 85 years of age or older, we computed Cohen d-based effect size estimations to compare the quantitative strength of each predictor variable in their contribution with exceptional aging without ADP. The study participants included 423 (45%) women and the average age of participants was 79.7 (5.9) years. Apart from demographics and the APOE genotype, only midlife dyslipidemia was associated with amyloid deposition. Obesity, smoking, diabetes, hypertension, and cardiac and metabolic conditions, but not

  17. Refinement of the experimental dynamic structure factor for liquid para-hydrogen and ortho-deuterium using semi-classical quantum simulation.

    PubMed

    Smith, Kyle K G; Poulsen, Jens Aage; Cunsolo, A; Rossky, Peter J

    2014-01-21

    The dynamic structure factor of liquid para-hydrogen and ortho-deuterium in corresponding thermodynamic states (T = 20.0 K, n = 21.24 nm(-3)) and (T = 23.0 K, n = 24.61 nm(-3)), respectively, has been computed by both the Feynman-Kleinert linearized path-integral (FK-LPI) and Ring-Polymer Molecular Dynamics (RPMD) methods and compared with Inelastic X Ray Scattering spectra. The combined use of computational and experimental methods enabled us to reduce experimental uncertainties in the determination of the true sample spectrum. Furthermore, the refined experimental spectrum of para-hydrogen and ortho-deuterium is consistently reproduced by both FK-LPI and RPMD results at momentum transfers lower than 12.8 nm(-1). At larger momentum transfers the FK-LPI results agree with experiment much better for ortho-deuterium than for para-hydrogen. More specifically we found that for k ∼ 20.0 nm(-1) para-hydrogen provides a test case for improved approximations to quantum dynamics.

  18. An experimental extrapolation technique using the Gafchromic EBT3 film for relative output factor measurements in small x-ray fields

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

    Morales, Johnny E., E-mail: johnny.morales@lh.org.

    Purpose: An experimental extrapolation technique is presented, which can be used to determine the relative output factors for very small x-ray fields using the Gafchromic EBT3 film. Methods: Relative output factors were measured for the Brainlab SRS cones ranging in diameters from 4 to 30 mm{sup 2} on a Novalis Trilogy linear accelerator with 6 MV SRS x-rays. The relative output factor was determined from an experimental reducing circular region of interest (ROI) extrapolation technique developed to remove the effects of volume averaging. This was achieved by scanning the EBT3 film measurements with a high scanning resolution of 1200 dpi.more » From the high resolution scans, the size of the circular regions of interest was varied to produce a plot of relative output factors versus area of analysis. The plot was then extrapolated to zero to determine the relative output factor corresponding to zero volume. Results: Results have shown that for a 4 mm field size, the extrapolated relative output factor was measured as a value of 0.651 ± 0.018 as compared to 0.639 ± 0.019 and 0.633 ± 0.021 for 0.5 and 1.0 mm diameter of analysis values, respectively. This showed a change in the relative output factors of 1.8% and 2.8% at these comparative regions of interest sizes. In comparison, the 25 mm cone had negligible differences in the measured output factor between zero extrapolation, 0.5 and 1.0 mm diameter ROIs, respectively. Conclusions: This work shows that for very small fields such as 4.0 mm cone sizes, a measureable difference can be seen in the relative output factor based on the circular ROI and the size of the area of analysis using radiochromic film dosimetry. The authors recommend to scan the Gafchromic EBT3 film at a resolution of 1200 dpi for cone sizes less than 7.5 mm and to utilize an extrapolation technique for the output factor measurements of very small field dosimetry.« less

  19. Discomfort Intolerance: Evaluation of a Potential Risk Factor for Anxiety Psychopathology

    ERIC Educational Resources Information Center

    Schmidt, Norman B.; Richey, J. Anthony; Cromer, Kiara R.; Buckner, Julia D.

    2007-01-01

    Discomfort intolerance, defined as an individual difference in the capacity to tolerate unpleasant bodily sensations, is a construct recently posited as a risk factor for panic and anxiety psychopathology. The present report used a biological challenge procedure to evaluate whether discomfort intolerance predicts fearful responding beyond the…

  20. Experimental evaluation of a fixed collector employing vee-trough concentrator and vacuum tube receivers

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K.

    1977-01-01

    A test bed for experimental evaluation of a fixed solar collector which combines an evacuated glass tube solar receiver with a flat plate/black chrome plated copper absorber and an asymmetric vee-trough concentrator was designed and constructed. Earlier predictions of thermal performance were compared with test data acquired for a bare vacuum tube receiver; and receiver tubes with Alzak aluminum, aluminized FEP Teflon film laminated sheet metal and second surface ordinary mirror reflectors. Test results and system economics as well as objectives of an ongoing program to obtain long-term performance data are discussed.

  1. Nondestructive evaluation tools and experimental studies for monitoring the health of space propulsion systems

    NASA Technical Reports Server (NTRS)

    Generazio, Edward R.

    1991-01-01

    An overview is given of background and information on space propulsion systems on both the programmatic and technical levels. Feasibility experimental studies indicate that nondestructive evaluation tools such as ultrasonic, eddy current and x-ray may be successfully used to monitor the life limiting failure mechanisms of space propulsion systems. Encouraging results were obtained for monitoring the life limiting failure mechanisms for three space propulsion systems; the degradation of tungsten arcjet and magnetoplasmadynamic electrodes; presence and thickness of spallable electrically conducting molybdenum films in ion thrusters; and the degradation of the catalyst in hydrazine thrusters.

  2. Experimental evaluation of neural probe’s insertion induced injury based on digital image correlation method

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

    Zhang, Wenguang, E-mail: zhwg@sjtu.edu.cn; Ma, Yakun; Li, Zhengwei

    Purpose: The application of neural probes in clinic has been challenged by probes’ short lifetime when implanted into brain tissue. The primary goal is to develop an evaluation system for testing brain tissue injury induced by neural probe’s insertion using microscope based digital image correlation method. Methods: A brain tissue phantom made of silicone rubber with speckle pattern on its surface was fabricated. To obtain the optimal speckle pattern, mean intensity gradient parameter was used for quality assessment. The designed testing system consists of three modules: (a) load module for simulating neural electrode implantation process; (b) data acquisition module tomore » capture micrographs of speckle pattern and to obtain reactive forces during the insertion of the probe; (c) postprocessing module for extracting tissue deformation information from the captured speckle patterns. On the basis of the evaluation system, the effects of probe wedge angle, insertion speed, and probe streamline on insertion induced tissue injury were investigated. Results: The optimal quality speckle pattern can be attained by the following fabrication parameters: spin coating rate—1000 r/min, silicone rubber component A: silicone rubber component B: softener: graphite = 5 ml: 5 ml: 2 ml: 0.6 g. The probe wedge angle has a significant effect on tissue injury. Compared to wedge angle 40° and 20°, maximum principal strain of 60° wedge angle was increased by 40.3% and 87.5%, respectively; compared with a relatively higher speed (500 μm/s), the maximum principle strain within the tissue induced by slow insertion speed (100 μm/s) was increased by 14.3%; insertion force required by probe with convex streamline was smaller than the force of traditional probe. Based on the experimental results, a novel neural probe that has a rounded tip covered by a biodegradable silk protein coating with convex streamline was proposed, which has both lower insertion and micromotion induced

  3. An Evaluation of the Experimental Anthropology Program at Magee Secondary School, During the Spring Semester of 1971.

    ERIC Educational Resources Information Center

    Clinton, A.; And Others

    An evaluation of an experimental anthropology program which was introduced to students at the Magee Secondary School is presented. The purpose of the course, a detailed course outline, and the rationale and basic generalizations of Anthropology 11E are included. A listing of required and suggested course readings as well as student reaction to the…

  4. Performance Evaluation of an Experimental Turbojet Engine

    NASA Astrophysics Data System (ADS)

    Ekici, Selcuk; Sohret, Yasin; Coban, Kahraman; Altuntas, Onder; Karakoc, T. Hikmet

    2017-11-01

    An exergy analysis is presented including design parameters and performance assessment, by identifying the losses and efficiency of a gas turbine engine. The aim of this paper is to determine the performance of a small turbojet engine with an exergetic analysis based on test data. Experimental data from testing was collected at full-load of small turbojet engine. The turbojet engine exhaust data contains CO2, CO, CH4, H2, H2O, NO, NO2, N2 and O2 with a relative humidity of 35 % for the ambient air of the performed experiments. The evaluated main components of the turbojet engine are the air compressor, the combustion chamber and the gas turbine. As a result of the thermodynamic analysis, exergy efficiencies (based on product/fuel) of the air compressor, the combustion chamber and the gas turbine are 81.57 %, 50.13 % and 97.81 %, respectively. A major proportion of the total exergy destruction was found for the combustion chamber at 167.33 kW. The exergy destruction rates are 8.20 %, 90.70 % and 1.08 % in the compressor, the combustion chamber and the gas turbine, respectively. The rates of exergy destruction within the system components are compared on the basis of the exergy rate of the fuel provided to the engine. Eventually, the exergy rate of the fuel is calculated to be 4.50 % of unusable due to exergy destruction within the compressor, 49.76 % unusable due to exergy destruction within the combustion chamber and 0.59 % unusable due to exergy destruction within the gas turbine. It can be stated that approximately 55 % of the exergy rate of the fuel provided to the engine can not be used by the engine.

  5. Experimental evaluation of a flexible I/O architecture for accelerating workflow engines in ultrascale environments

    DOE PAGES

    Duro, Francisco Rodrigo; Blas, Javier Garcia; Isaila, Florin; ...

    2016-10-06

    The increasing volume of scientific data and the limited scalability and performance of storage systems are currently presenting a significant limitation for the productivity of the scientific workflows running on both high-performance computing (HPC) and cloud platforms. Clearly needed is better integration of storage systems and workflow engines to address this problem. This paper presents and evaluates a novel solution that leverages codesign principles for integrating Hercules—an in-memory data store—with a workflow management system. We consider four main aspects: workflow representation, task scheduling, task placement, and task termination. As a result, the experimental evaluation on both cloud and HPC systemsmore » demonstrates significant performance and scalability improvements over existing state-of-the-art approaches.« less

  6. Using the Bayes Factors to Evaluate Person Fit in the Item Response Theory

    ERIC Educational Resources Information Center

    Pan, Tianshu; Yin, Yue

    2017-01-01

    In this article, we propose using the Bayes factors (BF) to evaluate person fit in item response theory models under the framework of Bayesian evaluation of an informative diagnostic hypothesis. We first discuss the theoretical foundation for this application and how to analyze person fit using BF. To demonstrate the feasibility of this approach,…

  7. An experimental evaluation of an effective medium based compaction equation.

    PubMed

    Mahmoodi, Foad; Alderborn, Göran; Frenning, Göran

    2012-05-12

    Tablet production involves compression of free flowing powder in an enclosed cavity of defined geometry. The complexity of the powder bed system necessitates that a way be found to better understand what occurs during compression. One such approach is by means of compaction equations, of which, the Heckel and Kawakita equations are the best known. This work attempts to experimentally evaluate the applicability of the effective medium (EM) equation introduced by Frenning et al. (2009) to powder systems. Two powder types (sodium chloride and lactose monohydrate), each consisting of three size fractions (<40, 125-212 and 212-300μm) were characterised and compressed to a pressure of 500MPa. These powders were chosen because of their differing mechanical properties. An invariance which is inherent in the EM equation is exposed by varying the starting points of compression, and can yield insights into compression mechanisms. Such invariant regions were observed once plastic particle deformation started to dominate the compression behaviour, and enabled the determination of the point where particle rearrangement stops. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 1 - mechanical properties of FRP piles.

    DOT National Transportation Integrated Search

    2014-10-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 1, Mechanical Properties of FRP Piles. : Mechanical and geotechnic...

  9. Experimental Evaluation of Journal Bearing Stability and New Gas Bearing Material

    NASA Technical Reports Server (NTRS)

    Keith, Theo G., Jr.; Dimofte, Florin

    2001-01-01

    It has been estimated that the noise levels in aircraft engine transmissions can be reduced by as much as 10 dB through the use of journal bearings. The potential benefits of lower noise levels include reduced wear, longer gear life and enhanced comfort for passengers and crew. Based on this concept the journal-thrust wave bearing was analyzed and its performance was evaluated. Numerical codes, developed over the past 30 years by Dr. Dimofte, were used to predict the performance of the bearing. The wave bearing is a fluid film bearing and therefore was analyzed using the Reynolds pressure equation. The formulation includes turbulent flow concepts and possesses a viscosity-temperature correction. The centrifugal growth of the bearing diameter and the deformation of the bearing under gear loads were also incorporated into the code. An experimental rig was developed to test the journal-thrust wave bearing.

  10. 48 CFR 252.215-7005 - Evaluation Factor for Employing or Subcontracting With Members of the Selected Reserve.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Evaluation Factor for... Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS SYSTEM, DEPARTMENT OF DEFENSE CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions And Clauses 252.215-7005 Evaluation Factor for...

  11. Evaluating the Evidence for the General Factor of Personality across Multiple Inventories

    PubMed Central

    Hopwood, Christopher J.; Wright, Aidan G.C.; Donnellan, M. Brent

    2012-01-01

    A general factor of personality (GFP) has been proposed as the apex of a personality trait hierarchy that explains covariance among the lower-order factors measured by various personality inventories. In this study we evaluated the GFP hypothesis across several personality inventories, unlike most previous research in which the GFP has been derived from individual instruments in isolation. Exploratory analyses did not produce substantial evidence for the existence of a single cross-instrument higher-order factor of factors and efforts to specify a range of GFP-inspired models in a confirmatory framework led to significant estimation difficulties and poor fit to the data. Overall these results fail to support a common GFP that is positioned at the top of a personality trait hierarchy. PMID:22879686

  12. Experimental evaluation of new chitin-chitosan graft for duraplasty.

    PubMed

    Pogorielov, M; Kravtsova, A; Reilly, G C; Deineka, V; Tetteh, G; Kalinkevich, O; Pogorielova, O; Moskalenko, R; Tkach, G

    2017-02-01

    Natural materials such as collagen and alginate have promising applications as dural graft substitutes. These materials are able to restore the dural defect and create optimal conditions for the development of connective tissue at the site of injury. A promising material for biomedical applications is chitosan-a linear polysaccharide obtained by the deacetylation of chitin. It has been found to be nontoxic, biodegradable, biofunctional and biocompatible in addition to having antimicrobial characteristics. In this study we designed new chitin-chitosan substitutes for dura mater closure and evaluated their effectiveness and safety. Chitosan films were produced from 3 % of chitosan (molar mass-200, 500 or 700 kDa, deacetylation rate 80-90%) with addition of 20% of chitin. Antimicrobial effictively and cell viability were analysed for the different molar masses of chitosan. The film containing chitosan of molar mass 200 kDa, had the best antimicrobial and biological activity and was successfully used for experimental duraplasty in an in vivo model. In conclusion the chitin-chitosan membrane designed here met the requirements for a dura matter graft exhibiting the ability to support cell growth, inhibit microbial growth and biodegradade at an appropriate rate. Therefore this is a promising material for clinical duroplasty.

  13. Experimental evaluation of outer planets probe thermal insulation concepts

    NASA Technical Reports Server (NTRS)

    Grote, M. G.; Mezines, S. A.

    1976-01-01

    An experimental program was conducted to evaluate various thermal insulation concepts for use in the Outer Planets Probe (OPP) during entry and descent into the atmospheres of Jupiter, Saturn, and Uranus. Phenolic fiberglass honeycomb specimens representative of the OPP structure were packed and tested with various fillers: Thermal conductivity measurements were made over a temperature range of 300 K to 483 K and pressures from vacuum up to 10 atmospheres in helium and nitrogen gas environments. The conductivity results could not be fully explained so new test specimens were designed with improved venting characteristics, and tested to determine the validity of the original data. All of the conductivity data showed results that were substantially higher than expected. The original test data in helium were lower than the data from the redesigned specimens, probably due to inadequate venting of nitrogen gas from the original specimens. The thermal conductivity test results show only a marginal improvement in probe thermal protection performance for a filled honeycomb core compared to an unfilled core. In addition, flatwise tension tests showed a severe bond strength degradation due to the inclusion of either the powder or foam fillers. In view of these results, it is recommended that the baseline OPP design utilize an unfilled core.

  14. A human factors evaluation of Extravehicular Activity gloves

    NASA Technical Reports Server (NTRS)

    O'Hara, John M.; Briganti, Michael; Cleland, John; Winfield, Dan

    1989-01-01

    One of the major problems faced in Extravehicular Activity (EVA) glove development has been the absence of concise and reliable methods to measure the effects of EVA gloves on human-hand capabilities. NASA has sponsored a program to develop a standardized set of tests designed to assess EVA-gloved hand capabilities in six performance domains: Range of Motion, Strength, Tactile Perception, Dexterity, Fatigue, and Comfort. Based upon an assessment of general human-hand functioning and EVA task requirements, several tests within each performance domain were developed to provide a comprehensive evaluation. All tests were designed to be conducted in a glove box with the bare hand, an EVA glove without pressure, an EVA glove at operation pressure. Thus, the differential effect on performance of the glove with and without pressure was tested. Bare hand performance was used to 'calibrate' the effects. Ten subjects participated in the test setup as a repeated-measures experimental design. The paper will report the results of the test program.

  15. Platelet-Activating Factor (PAF) Receptor Antagonism Modulates Inflammatory Signaling in Experimental Uveitis.

    PubMed

    Elison, Jasmine R; Weinstein, Jessica E; Sheets, Kristopher G; Regan, Cornelius E; Lentz, Jennifer J; Reinoso, Maria; Gordon, William C; Bazan, Nicolas G

    2018-04-11

    The phospholipid mediator platelet-activating factor (PAF) activates an inflammatory response that includes arachidonic acid release and prostaglandin production in the eye, increasing vascular permeability and inflammation. The purpose of this study is to investigate the action of LAU-0901, a novel PAF receptor antagonist, on experimental uveitis. Uveitis was induced in Lewis rats by lipopolysaccharide treatment. LAU-0901 was then delivered systemically in different concentrations at plus 4 and 16 hours, or vehicle injected as controls. Additional animals were used for histological analyses of untreated, uveitis, and uveitis-plus-LAU-0901 retinas. Conventional histological and immunohistochemical methods were employed. A slit lamp and Spectral Domain-Ocular Coherence Tomography (SD-OCT) retinal imager was used for anterior segment photography and posterior pole OCT. Rats were euthanized 4 hours after the second LAU-0901 injection in this 24-hour model. Aqueous humor was collected and quantified, and also analyzed for tumor necrosis factor alpha (TNF-α). Uveitic eyes demonstrated hypopyon formation, leukocyte infiltration, and an increase in aqueous protein and TNF-α levels. LAU-0901 treatment resulted in a dose-dependent reduction in inflammation, reflected by reduced total protein levels (up to a 64% reduction). Moreover, hypopyon was prevented, leukocytes were absent in vitreous and aqueous humor, and TNF-α levels were reduced by 91%. The PAF receptor antagonist LAU-0901 decreases ocular inflammation in a rat model of anterior uveitis in a dose-dependent manner, suggesting that use of this molecule may provide a means to attenuate inflammation onset and offer a future alternative or adjunctive treatment for ocular inflammation.

  16. Evaluating Journal Quality: Is the H-Index a Better Measure than Impact Factors?

    ERIC Educational Resources Information Center

    Hodge, David R.; Lacasse, Jeffrey R.

    2011-01-01

    Objectives: This study evaluates the utility of a new measure--the h-index--that may provide a more valid approach to evaluating journal quality in the social work profession. Method: H-index values are compared with Thomson ISI 5-year impact factors and expert opinion. Results: As hypothesized, the h-index correlates highly with ISI 5-year impact…

  17. Experimental design matters for statistical analysis: how to handle blocking.

    PubMed

    Jensen, Signe M; Schaarschmidt, Frank; Onofri, Andrea; Ritz, Christian

    2018-03-01

    Nowadays, evaluation of the effects of pesticides often relies on experimental designs that involve multiple concentrations of the pesticide of interest or multiple pesticides at specific comparable concentrations and, possibly, secondary factors of interest. Unfortunately, the experimental design is often more or less neglected when analysing data. Two data examples were analysed using different modelling strategies. First, in a randomized complete block design, mean heights of maize treated with a herbicide and one of several adjuvants were compared. Second, translocation of an insecticide applied to maize as a seed treatment was evaluated using incomplete data from an unbalanced design with several layers of hierarchical sampling. Extensive simulations were carried out to further substantiate the effects of different modelling strategies. It was shown that results from suboptimal approaches (two-sample t-tests and ordinary ANOVA assuming independent observations) may be both quantitatively and qualitatively different from the results obtained using an appropriate linear mixed model. The simulations demonstrated that the different approaches may lead to differences in coverage percentages of confidence intervals and type 1 error rates, confirming that misleading conclusions can easily happen when an inappropriate statistical approach is chosen. To ensure that experimental data are summarized appropriately, avoiding misleading conclusions, the experimental design should duly be reflected in the choice of statistical approaches and models. We recommend that author guidelines should explicitly point out that authors need to indicate how the statistical analysis reflects the experimental design. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 3 - FRP composite pile flexural testing.

    DOT National Transportation Integrated Search

    2014-06-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 3, FRP Composite Pile Flexural Testing. : Hollow and concrete filled...

  19. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 5 : laminate durability testing : final report.

    DOT National Transportation Integrated Search

    2015-05-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 5, Laminate Durability Testing. : Mechanical properties of the FRP mat...

  20. Calculated X-ray Intensities Using Monte Carlo Algorithms: A Comparison to Experimental EPMA Data

    NASA Technical Reports Server (NTRS)

    Carpenter, P. K.

    2005-01-01

    Monte Carlo (MC) modeling has been used extensively to simulate electron scattering and x-ray emission from complex geometries. Here are presented comparisons between MC results and experimental electron-probe microanalysis (EPMA) measurements as well as phi(rhoz) correction algorithms. Experimental EPMA measurements made on NIST SRM 481 (AgAu) and 482 (CuAu) alloys, at a range of accelerating potential and instrument take-off angles, represent a formal microanalysis data set that has been widely used to develop phi(rhoz) correction algorithms. X-ray intensity data produced by MC simulations represents an independent test of both experimental and phi(rhoz) correction algorithms. The alpha-factor method has previously been used to evaluate systematic errors in the analysis of semiconductor and silicate minerals, and is used here to compare the accuracy of experimental and MC-calculated x-ray data. X-ray intensities calculated by MC are used to generate a-factors using the certificated compositions in the CuAu binary relative to pure Cu and Au standards. MC simulations are obtained using the NIST, WinCasino, and WinXray algorithms; derived x-ray intensities have a built-in atomic number correction, and are further corrected for absorption and characteristic fluorescence using the PAP phi(rhoz) correction algorithm. The Penelope code additionally simulates both characteristic and continuum x-ray fluorescence and thus requires no further correction for use in calculating alpha-factors.

  1. Human Factors in the Design and Evaluation of Air Traffic Control Systems

    DOT National Transportation Integrated Search

    1995-04-01

    This document presents human factors issues that should be considered in the design and evaluation of air traffic : control (ATC) systems and subsystems. It provides background material on the capabilities and limitations of humans as : information p...

  2. Likelihood-based modification of experimental crystal structure electron density maps

    DOEpatents

    Terwilliger, Thomas C [Sante Fe, NM

    2005-04-16

    A maximum-likelihood method for improves an electron density map of an experimental crystal structure. A likelihood of a set of structure factors {F.sub.h } is formed for the experimental crystal structure as (1) the likelihood of having obtained an observed set of structure factors {F.sub.h.sup.OBS } if structure factor set {F.sub.h } was correct, and (2) the likelihood that an electron density map resulting from {F.sub.h } is consistent with selected prior knowledge about the experimental crystal structure. The set of structure factors {F.sub.h } is then adjusted to maximize the likelihood of {F.sub.h } for the experimental crystal structure. An improved electron density map is constructed with the maximized structure factors.

  3. Course Factors That Motivate Students to Submit End-of-Course Evaluations

    ERIC Educational Resources Information Center

    Jaquett, Caroline M.; VanMaaren, Victoria G.; Williams, Robert L.

    2017-01-01

    We surveyed students (N = 152) in several sections of an undergraduate educational psychology course to determine what course factors would most motivate them to submit course evaluations. The survey directed students to choose among several pairs of course characteristics as to their relative impact on their decision to submit a course…

  4. Surface Irregularity Factor as a Parameter to Evaluate the Fatigue Damage State of CFRP

    PubMed Central

    Zuluaga-Ramírez, Pablo; Frövel, Malte; Belenguer, Tomás; Salazar, Félix

    2015-01-01

    This work presents an optical non-contact technique to evaluate the fatigue damage state of CFRP structures measuring the irregularity factor of the surface. This factor includes information about surface topology and can be measured easily on field, by techniques such as optical perfilometers. The surface irregularity factor has been correlated with stiffness degradation, which is a well-accepted parameter for the evaluation of the fatigue damage state of composite materials. Constant amplitude fatigue loads (CAL) and realistic variable amplitude loads (VAL), representative of real in- flight conditions, have been applied to “dog bone” shaped tensile specimens. It has been shown that the measurement of the surface irregularity parameters can be applied to evaluate the damage state of a structure, and that it is independent of the type of fatigue load that has caused the damage. As a result, this measurement technique is applicable for a wide range of inspections of composite material structures, from pressurized tanks with constant amplitude loads, to variable amplitude loaded aeronautical structures such as wings and empennages, up to automotive and other industrial applications. PMID:28793655

  5. Experimental Evaluation of the Tools of the Mind Pre-K Curriculum. Fidelity of Implementation Technical Report. Working Paper

    ERIC Educational Resources Information Center

    Meador, Deanna; Nesbitt, Kimberly; Farran, Dale

    2015-01-01

    The "Experimental Evaluation of the Tools of the Mind Pre-K Curriculum" study was designed to compare the effectiveness of the "Tools of the Mind" ("Tools") curriculum to the curricula the school system is currently using in enhancing children's self-regulation skills and their academic preparation for kindergarten.…

  6. Human Factors Experimental Design and Analysis Reference

    DTIC Science & Technology

    2007-07-01

    Equipment 1.4.5. Pretesting 1.5. Research Design Alternatives ………………………………………………………...30 1.6. Analyzing Results ……………………………………………………………………….31 1.7...46 2.1.1. Threats to Validity 2.1.2. Quantitative Research Approach 2.2. Experimental Design Alternatives...with a discussion of quantitative models in research that are used to predict human performance. Next empirical model building using polynomial

  7. Strain measurement on stiff structures: experimental evaluation of three integrated measurement principles

    NASA Astrophysics Data System (ADS)

    Rausch, J.; Hatzfeld, C.; Karsten, R.; Kraus, R.; Millitzer, J.; Werthschützky, R.

    2012-06-01

    This paper presents an experimental evaluation of three different strain measuring principles. Mounted on a steel beam resembling a car engine mount, metal foil strain gauges, piezoresistive silicon strain gauges and piezoelectric patches are investigated to measure structure-borne forces to control an active mounting structure. FEA simulation determines strains to be measured in the range of 10-8 up to 10-5 m × m-1. These low strains cannot be measured with conventional metal foil strain gauges, as shown in the experiment conducted. Both piezoresistive and piezoelectric gauges show good results compared to a conventional piezoelectric force sensor. Depending on bandwidth, overload capacity and primary electronic costs, these principles seem to be worth considering in an adaptronic system design. These parameters are described in detail for the principles investigated.

  8. Physiological Fluctuations in Brain Temperature as a Factor Affecting Electrochemical Evaluations of Extracellular Glutamate and Glucose in Behavioral Experiments

    PubMed Central

    2013-01-01

    The rate of any chemical reaction or process occurring in the brain depends on temperature. While it is commonly believed that brain temperature is a stable, tightly regulated homeostatic parameter, it fluctuates within 1–4 °C following exposure to salient arousing stimuli and neuroactive drugs, and during different behaviors. These temperature fluctuations should affect neural activity and neural functions, but the extent of this influence on neurochemical measurements in brain tissue of freely moving animals remains unclear. In this Review, we present the results of amperometric evaluations of extracellular glutamate and glucose in awake, behaving rats and discuss how naturally occurring fluctuations in brain temperature affect these measurements. While this temperature contribution appears to be insignificant for glucose because its extracellular concentrations are large, it is a serious factor for electrochemical evaluations of glutamate, which is present in brain tissue at much lower levels, showing smaller phasic fluctuations. We further discuss experimental strategies for controlling the nonspecific chemical and physical contributions to electrochemical currents detected by enzyme-based biosensors to provide greater selectivity and reliability of neurochemical measurements in behaving animals. PMID:23448428

  9. Identification of anthranilamide derivatives as potential factor Xa inhibitors: drug design, synthesis and biological evaluation.

    PubMed

    Xing, Junhao; Yang, Lingyun; Li, Hui; Li, Qing; Zhao, Leilei; Wang, Xinning; Zhang, Yuan; Zhou, Muxing; Zhou, Jinpei; Zhang, Huibin

    2015-05-05

    The coagulation enzyme factor Xa (fXa) plays a crucial role in the blood coagulation cascade. In this study, three-dimensional fragment based drug design (FBDD) combined with structure-based pharmacophore (SBP) model and structural consensus docking were employed to identify novel fXa inhibitors. After a multi-stage virtual screening (VS) workflow, two hit compounds 3780 and 319 having persistent high performance were identified. Then, these two hit compounds and several analogs were synthesized and screened for in-vitro inhibition of fXa. The experimental data showed that most of the designed compounds displayed significant in vitro potency against fXa. Among them, compound 9b displayed the greatest in vitro potency against fXa with the IC50 value of 23 nM and excellent selectivity versus thrombin (IC50 = 40 μM). Moreover, the prolongation of the prothrombin time (PT) was measured for compound 9b to evaluate its in vitro anticoagulant activity. As a result, compound 9b exhibited pronounced anticoagulant activity with the 2 × PT value of 8.7 μM. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  10. Human factors and education: evolution and contributions.

    PubMed

    Stone, Nancy J

    2008-06-01

    The major contributions of human factors to education are highlighted. Over the past 50 years, the education of human factors specialists has evolved, as well as the application of human factors and ergonomic knowledge to education. Human factors and ergonomics professional documentation and literature were reviewed to identify major events relevant to human factors education or the application of human factors to education. Human factors education has evolved from training in experimental psychology to highly specialized accredited human factors programs and a number of undergraduate programs, leading to program accreditation and the certification of professionals. In addition, human factors specialists have applied their knowledge to human factors education and, more recently, to educational systems in general. The greatest focus has been on technology such as multimedia. Others have evaluated the design of the physical environment, focusing primarily on seating. The research also often targets undergraduate or graduate education. Therefore, it has been proposed that a greater focus is needed at the K-12 educational level, especially given the advancement and implementation of technology in the classroom. Human factors and ergonomic expertise can benefit the educational system. Yet, there is a need to constantly evaluate the benefits of new technology in the classroom as well as the environmental design aspects of the educational environment while considering learners of different age groups, ethnicities, and sexes. Better application of human factors and ergonomics to the learning environment could enhance the educational experience for all learners.

  11. Experimental Evaluation of Grid Support Enabled PV Inverter Response to Abnormal Grid Conditions

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

    Nelson, Austin A; Martin, Gregory D; Hurtt, James

    As revised interconnection standards for grid-tied photovoltaic (PV) inverters address new advanced grid support functions (GSFs), there is increasing interest in inverter performance in the case of abnormal grid conditions. The growth of GSF-enabled inverters has outpaced the industry standards that define their operation, although recently published updates to UL1741 Supplement SA define test conditions for GSFs such as volt-var control, frequency-watt control, and voltage/frequency ride-through, among others. This paper describes the results of a comparative experimental evaluation on four commercially available, three-phase PV inverters in the 24.0-39.8 kVA power range on their GSF capability and its effect on abnormalmore » grid condition response. The evaluation examined the impact particular GSF implementations have on run-on times during islanding conditions, peak voltages in load rejection overvoltage scenarios, and peak currents during single-phase and three-phase fault events for individual inverters. Testing results indicated a wide variance in the performance of GSF enabled inverters to various test cases.« less

  12. Improving Ascertainment of Risk Factors for HIV Infection: Results of a Group-Randomized Evaluation

    ERIC Educational Resources Information Center

    Harrison, Kathleen McDavid; Pals, Sherri L.; Sajak, Tammy; Chase, Jennifer; Kajese, Tebitha

    2010-01-01

    To allow appropriate allocation of prevention and care funding, HIV/AIDS surveillance data must include risk factor information, currently available for less than 70% of cases reported in the United States. The authors evaluated an intervention consisting of provider training and materials to improve risk factor reporting. Facilities were matched…

  13. Effects of tacrolimus and erythropoietin in experimental spinal cord lesion in rats: functional and histological evaluation

    PubMed Central

    de Mesquita Coutinho, P R; Cristante, A F; de Barros Filho, T E P; Ferreira, R; dos Santos, G B

    2016-01-01

    Study design: Experimental study with rats. Objective: To evaluate functional and histological effects of tacrolimus (FK 506) and erythropoietin (EPO) after experimental spinal cord contusion injury (SCI). Setting: Brazil. Methods: Wistar rats (n=60) were submitted to SCI with the NYU Impactor system. The control group received saline; the EPO group received EPO; the group EPO+FK 506 received EPO associated with tacrolimus and the group FK 506 received tacrolimus only. The Sham group underwent SCI, but did not receive any drug. Locomotor function was evaluated after SCI by BBB (Basso, Beattie and Bresnahan) weekly and by the motor-evoked potential test in 42 days. The spinal cord was histologically evaluated. Results: There was a significant difference between treated and the control groups from the seventh day on for BBB scores, with no difference between the groups EPO and EPO+FK 506 by the end of the study. There were significant differences between groups for necrosis and bleeding, but not for hiperemia, degeneration and cellular infiltrate. Axon neuron count was different between all groups (P=0.001), between EPO+FK 506 and FK 506 (P=0.011) and between EPO+FK 506 and Sham (P=0.002). Amplitude was significantly different between all groups except between control and sham. For latency, there was no difference. Conclusions: This study did not reveal significant differences in the recovery of locomotor function, or in the histological and electrophysiological analysis in animals treated with EPO and tacrolimus after thoracic SCI. PMID:26481712

  14. Evaluation of the therapeutic effect of potassium permanganate at early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus)

    USDA-ARS?s Scientific Manuscript database

    The efficacy of potassium permanganate (KMnO4) against early stages of an experimental acute infection of Flavobacterium columnare in channel catfish (Ictalurus punctatus) was evaluated. Fish were experimentally challenged, by waterborne exposure for 2 h to F. columnare after cutaneous abrasion, an...

  15. Single-Case Experimental Designs to Evaluate Novel Technology-Based Health Interventions

    PubMed Central

    Cassidy, Rachel N; Raiff, Bethany R

    2013-01-01

    Technology-based interventions to promote health are expanding rapidly. Assessing the preliminary efficacy of these interventions can be achieved by employing single-case experiments (sometimes referred to as n-of-1 studies). Although single-case experiments are often misunderstood, they offer excellent solutions to address the challenges associated with testing new technology-based interventions. This paper provides an introduction to single-case techniques and highlights advances in developing and evaluating single-case experiments, which help ensure that treatment outcomes are reliable, replicable, and generalizable. These advances include quality control standards, heuristics to guide visual analysis of time-series data, effect size calculations, and statistical analyses. They also include experimental designs to isolate the active elements in a treatment package and to assess the mechanisms of behavior change. The paper concludes with a discussion of issues related to the generality of findings derived from single-case research and how generality can be established through replication and through analysis of behavioral mechanisms. PMID:23399668

  16. Hepatocellular hypoxia-induced vascular endothelial growth factor expression and angiogenesis in experimental biliary cirrhosis.

    PubMed

    Rosmorduc, O; Wendum, D; Corpechot, C; Galy, B; Sebbagh, N; Raleigh, J; Housset, C; Poupon, R

    1999-10-01

    We tested the potential role of vascular endothelial growth factor (VEGF) and of fibroblast growth factor-2 (FGF-2) in the angiogenesis associated with experimental liver fibrogenesis induced by common bile duct ligation in Sprague-Dawley rats. In normal rats, VEGF and FGF-2 immunoreactivities were restricted to less than 3% of hepatocytes. One week after bile duct ligation, hypoxia was demonstrated by the immunodetection of pimonidazole adducts unevenly distributed throughout the lobule. After 2 weeks, hypoxia and VEGF expression were detected in >95% of hepatocytes and coexisted with an increase in periportal vascular endothelial cell proliferation, as ascertained by Ki67 immunolabeling. Subsequently, at 3 weeks the density of von Willebrand-labeled vascular section in fibrotic areas significantly increased. Semiquantitative reverse transcription polymerase chain reaction showed that VEGF(120) and VEGF(164) transcripts, that correspond to secreted isoforms, increased within 2 weeks, while VEGF(188) transcripts remained unchanged. FGF-2 mainly consisting of a 22-kd isoform, according to Western blot, was identified by immunohistochemistry in 49% and 100% of hepatocytes at 3 and 7 weeks, respectively. Our data provide evidence that in biliary-type liver fibrogenesis, angiogenesis is stimulated primarily by VEGF in response to hepatocellular hypoxia while FGF-2 likely contributes to the maintenance of angiogenesis at later stages.

  17. Evaluation as a critical factor of success in local public health accreditation programs.

    PubMed

    Tremain, Beverly; Davis, Mary; Joly, Brenda; Edgar, Mark; Kushion, Mary L; Schmidt, Rita

    2007-01-01

    This article presents the variety of approaches used to conduct evaluations of performance improvement or accreditation systems, while illustrating the complexity of conducting evaluations to inform local public health practice. We, in addition, hope to inform the Exploring Accreditation Program about relevant experiences involving accreditation and performance assessment processes, specifically evaluation, as it debates and discusses a national voluntary model. A background of each state is given. To further explore these issues, interviews were conducted with each state's evaluator to gain more in-depth information on the many different evaluation strategies and approaches used. On the basis of the interviews, the authors provide several overall themes, which suggest that evaluation is a critical tool and success factor for performance assessment or accreditation programs.

  18. 48 CFR 852.219-72 - Evaluation factor for participation in the VA mentor-protégé program.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... participation in the VA mentor-protégé program. 852.219-72 Section 852.219-72 Federal Acquisition Regulations... Texts of Provisions and Clauses 852.219-72 Evaluation factor for participation in the VA mentor-protégé... the VA Mentor-Protégé Program (DEC2009) This solicitation contains an evaluation factor or sub-factor...

  19. Experimental evaluation of fog warning system.

    PubMed

    Al-Ghamdi, Ali S

    2007-11-01

    Highway safety is a major concern to the public and to transportation professionals, so the number of crashes caused by poor visibility due to fog form an alarming statistic. Drivers respond to poor visibility conditions in different ways: some slow down; others do not. Many drivers simply follow the taillights of the vehicle ahead. Accordingly, hazardous conditions are created in which speeds are both too high for the prevailing conditions and highly variable. Findings are presented from a study of traffic crashes due to fog in the southern region of Saudi Arabia. The primary objective was to assess the effectiveness of fog detection and warning system on driver behavior regarding speed and headway. This warning system includes visibility sensors that automatically activate a variable message sign that posts an advisory speed when hazardous conditions due to fog occur. The system was installed on a 2 km section of a two-lane, rural highway. A data set of 36,013 observations from both experimental and control sections at two study sites was collected and analyzed. The data included vehicle speed, volume, and classification; time headway, time of day, and visibility distance. Although the warning system was ineffective in reducing speed variability, mean speed throughout the experimental sections was reduced by about 6.5 kph. This reduction indicates that the warning system appeared to have a positive effect on driver behavior in fog even though the observed mean speeds were still higher than the posted advisory speed. From relationships found in the literature between mean driving speed and number of crashes, a speed reduction of only 5 kph would yield a 15% decrease in the number of crashes.

  20. Evaluation of risk factors for vancomycin-induced nephrotoxicity.

    PubMed

    Park, So Jin; Lim, Na Ri; Park, Hyo Jung; Yang, Jae Wook; Kim, Min-Ji; Kim, Kyunga; In, Yong Won; Lee, Young Mee

    2018-05-09

    Background Vancomycin is a glycopeptide antibiotic of choice for the treatment of serious infections caused by multi-resistant Gram-positive bacteria. However, vancomycin-associated nephrotoxicity (VAN) often limits its use. Previous data suggested a few risk factors of VAN, including higher mean vancomycin trough level, higher daily doses, old age, long duration of vancomycin therapy, and concomitant nephrotoxins. Objective To evaluate the incidence and risk factors of VAN and determine whether higher vancomycin trough concentrations were associated with a greater risk for VAN. Settings A retrospective, observational, single-center study at the 1960-bed university-affiliated tertiary care hospital (Samsung Medical Center), Seoul, Korea. Method A retrospective analysis of adult patients who received vancomycin parenterally in a tertiary care medical center from March 1, 2013 to June 30, 2013 was performed. We excluded patients with a baseline serum creatinine level > 2 mg/dL and those who had a history of end-stage renal disease and dialysis at baseline. The clinical characteristics were compared between patients with nephrotoxicity and those without nephrotoxicity to identify the risk factors associated with VAN. Main outcome measure Incidence of VAN and VAN-associated risk factors were analyzed. Results Of the 315 vancomycin-treated patients, nephrotoxicity occurred in 15.2% of the patients. In multivariate analysis, higher vancomycin trough concentrations of > 20 mg∕L (OR 9.57, 95% CI 2.49-36.83, p < 0.01) and intensive care unit (ICU) residence (OR 2.86, 95% CI 1.41-5.82, p < 0.01) were independently associated with VAN. Conclusion Our findings suggest that higher vancomycin trough levels and ICU residence might be associated with a greater risk for VAN. More careful monitoring of vancomycin serum trough levels and patient status might facilitate the timely prevention of VAN.

  1. Refinement of the experimental dynamic structure factor for liquid para-hydrogen and ortho-deuterium using semi-classical quantum simulation

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

    Smith, Kyle K. G., E-mail: kylesmith@utexas.edu; Rossky, Peter J., E-mail: peter.rossky@austin.utexas.edu; Poulsen, Jens Aage, E-mail: jens72@chem.gu.se

    The dynamic structure factor of liquid para-hydrogen and ortho-deuterium in corresponding thermodynamic states (T = 20.0 K, n = 21.24 nm{sup −3}) and (T = 23.0 K, n = 24.61 nm{sup −3}), respectively, has been computed by both the Feynman-Kleinert linearized path-integral (FK-LPI) and Ring-Polymer Molecular Dynamics (RPMD) methods and compared with Inelastic X Ray Scattering spectra. The combined use of computational and experimental methods enabled us to reduce experimental uncertainties in the determination of the true sample spectrum. Furthermore, the refined experimental spectrum of para-hydrogen and ortho-deuterium is consistently reproduced by both FK-LPI and RPMD results at momentum transfers lower than 12.8 nm{sup −1}.more » At larger momentum transfers the FK-LPI results agree with experiment much better for ortho-deuterium than for para-hydrogen. More specifically we found that for k ∼ 20.0 nm{sup −1} para-hydrogen provides a test case for improved approximations to quantum dynamics.« less

  2. Use of the Theoretical Domains Framework to evaluate factors driving successful implementation of the Accelerated Chest pain Risk Evaluation (ACRE) project.

    PubMed

    Skoien, Wade; Page, Katie; Parsonage, William; Ashover, Sarah; Milburn, Tanya; Cullen, Louise

    2016-10-12

    The translation of healthcare research into practice is typically challenging and limited in effectiveness. The Theoretical Domains Framework (TDF) identifies 12 domains of behaviour determinants which can be used to understand the principles of behavioural change, a key factor influencing implementation. The Accelerated Chest pain Risk Evaluation (ACRE) project has successfully translated research into practice, by implementing an intervention to improve the assessment of low to intermediate risk patients presenting to emergency departments (EDs) with chest pain. The aims of this paper are to describe use of the TDF to determine which factors successfully influenced implementation and to describe use of the TDF as a tool to evaluate implementation efforts and which domains are most relevant to successful implementation. A 30-item questionnaire targeting clinicians was developed using the TDF as a guide. Questions encompassed ten of the domains of the TDF: Knowledge; Skills; Social/professional role and identity; Beliefs about capabilities; Optimism; Beliefs about consequences; Intentions; Memory, attention and decision processes; Environmental context and resources; and Social influences. Sixty-three of 176 stakeholders (36 %) responded to the questionnaire. Responses for all scales showed that respondents were highly favourable to all aspects of the implementation. Scales with the highest mean responses were Intentions, Knowledge, and Optimism, suggesting that initial education and awareness strategies around the ACRE project were effective. Scales with the lowest mean responses were Environmental context and resources, and Social influences, perhaps highlighting that implementation planning could have benefitted from further consideration of the factors underlying these scales. The ACRE project was successful, and therefore, a perfect case study for understanding factors which drive implementation success. The overwhelmingly positive response suggests that it

  3. Factors influencing general practitioners' decisions about cardiovascular disease risk reassessment: findings from experimental and interview studies.

    PubMed

    McKinn, Shannon; Bonner, Carissa; Jansen, Jesse; Teixeira-Pinto, Armando; So, Matthew; Irwig, Les; Doust, Jenny; Glasziou, Paul; McCaffery, Kirsten

    2016-08-05

    Guidelines on cardiovascular disease (CVD) risk reassessment intervals are unclear, potentially leading to detrimental practice variation: too frequent can result in overtreatment and greater strain on the healthcare system; too infrequent could result in the neglect of high risk patients who require medication. This study aimed to understand the different factors that general practitioners (GPs) consider when deciding on the reassessment interval for patients previously assessed for primary CVD risk. This paper combines quantitative and qualitative data regarding reassessment intervals from two separate studies of CVD risk management. Experimental study: 144 Australian GPs viewed a random selection of hypothetical cases via a paper-based questionnaire, in which blood pressure, cholesterol and 5-year absolute risk (AR) were systematically varied to appear lower or higher. GPs were asked how they would manage each case, including an open-ended response for when they would reassess the patient. Interview study: Semi-structured interviews were conducted with a purposive sample of 25 Australian GPs, recruited separately from the GPs in the experimental study. Transcribed audio-recordings were thematically coded, using the Framework Analysis method. GPs stated that they would reassess the majority of patients across all absolute risk categories in 6 months or less (low AR = 52 % [CI95% = 47-57 %], moderate AR = 82 % [CI95% = 76-86 %], high AR = 87 % [CI95% = 82-90 %], total = 71 % [CI95% = 67-75 %]), with 48 % (CI95% = 43-53 %) of patients reassessed in under 3 months. The majority (75 % [CI95% = 70-79 %]) of patients with low-moderate AR (≤15 %) and an elevated risk factor would be reassessed in under 6 months. Interviews: GPs identified different functions for reassessment and risk factor monitoring, which affected recommended intervals. These included perceived psychosocial benefits to patients, preparing the

  4. Heparin-binding EGF-like growth factor and enteric neural stem cell transplantation in the prevention of experimental necrotizing enterocolitis in mice.

    PubMed

    Wei, Jia; Zhou, Yu; Besner, Gail E

    2015-07-01

    Necrotizing enterocolitis (NEC) is associated with loss of neurons and glial cells in the enteric nervous system (ENS). Our goal was to determine whether enteric neural stem cell (NSC) transplantation, in conjunction with heparin-binding epidermal growth factor-like growth factor (HB-EGF), could protect against experimental NEC. In vitro, HB-EGF on NSC proliferation and migration, and the effects of receptors utilized by HB-EGF to exert these effects, were determined. In vivo, mouse pups were exposed to experimental NEC and treated with NSC alone, HB-EGF alone, NSC+HB-EGF, or HB-EGF overexpressing NSC. NSC engraftment and differentiation into neurons in the ENS, intestinal injury, intestinal permeability, and intestinal motility were determined. HB-EGF promoted NSC proliferation via ErbB-1 receptors and enhanced NSC migration via ErbB-1, ErbB-4, and Nardilysin receptors. HB-EGF significantly enhanced the engraftment of transplanted NSC into the ENS during NEC. NSC transplantation significantly reduced NEC incidence and improved gut barrier function and intestinal motility, and these effects were augmented by simultaneous administration of HB-EGF or by transplantation of HB-EGF overexpressing NSC. HB-EGF promotes NSC proliferation and migration. HB-EGF and NSC reduce intestinal injury and improve gut barrier function and intestinal motility in experimental NEC. Combined HB-EGF and NSC transplantation may represent a potential future therapy to prevent NEC.

  5. Experimental evaluation of a 600 lbf spacecraft rocket engine.

    NASA Technical Reports Server (NTRS)

    Hoehn, F. W.

    1972-01-01

    Experimental results are presented for a long-duration-capability (1000-sec), space-storable, bipropellant liquid rocket motor burning fluorine/hydrazine or FLOX/monomethylhydrazine. The interrelationship between injected mixture ratio and the per cent film cooling on vacuum specific impulse performance and chamber heat transfer is given. Experimental sea level measurements are used to predict space vacuum performance based upon simplified JANNAF reference procedures. Dynamic combustion stability is demonstrated over a wide range of operating conditions. Analytical results of char penetration, erosion, and ablative wall temperature distributions are presented for prototype chamber designs.

  6. A Computer Program to Evaluate Experimental Therapies for Treating Burned Patients

    PubMed Central

    Flora, Jairus D.; Flora, Sharyl Ann

    1980-01-01

    Determining the worth of new therapies for burn patients has been difficult because of the rarity of the burn injury and the disparate survival chances associated with different sizes of burns. Recently a burn survival model has been developed that estimates the risk of death from a burn as a function of the patient's age, sex, area of full thickness (third degree) burn, area of partial thickness burn, involvement of the perineum, and time from burn to admission. An alternative risk model uses the total area burned in place of the areas of partial thickness burn and full thickness burn, and is appropriate if the amount of full thickness burn is not determined accurately. This paper describes a program that uses these risk models to correct or standardize for demographic and severity factors, then, after that adjustment, tests whether a group of burn patients who received a new or experimental therapy shows a significantly better survival rate than that predicted by a baseline model. The program is a simple one written in Fortran for easy adaptation to other computer systems.

  7. Evaluation of aldehyde dehydrogenase 1 and transcription factors in both primary breast cancer and axillary lymph node metastases as a prognostic factor.

    PubMed

    Ito, Maiko; Shien, Tadahiko; Omori, Masako; Mizoo, Taeko; Iwamoto, Takayuki; Nogami, Tomohiro; Motoki, Takayuki; Taira, Naruto; Doihara, Hiroyoshi; Miyoshi, Shinichiro

    2016-05-01

    Aldehyde dehydrogenase 1 (ALDH1) is a marker of breast cancer stem cells, and the expression of ALDH1 may be a prognostic factor of poor clinical outcome. The epithelial-mesenchymal transition may produce cells with stem-cell-like properties promoted by transcription factors. We investigated the expression of ALDH1 and transcription factors in both primary and metastatic lesions, and prognostic value of them in breast cancer patients with axillary lymph node metastasis (ALNM). Forty-seven breast cancer patients with ALNM who underwent surgery at Okayama University Hospital from 2002 to 2008 were enrolled. We retrospectively evaluated the levels of ALDH1 and transcription factors, such as Snail, Slug and Twist, in both primary and metastatic lesions by immunohistochemistry. In primary lesions, the positive rate of ALDH1, Snail, Slug and Twist was 19, 49, 40 and 26%, respectively. In lymph nodes, that of ALDH1, Snail, Slug and Twist was 21, 32, 13 and 23%, respectively. The expression of ALDH1 or transcription factors alone was not significantly associated with a poor prognosis. However, co-expression of ALDH1 and Slug in primary lesions was associated with a shorter DFS (P = 0.009). The evaluation of the co-expression of ALDH1 and transcription factors in primary lesions may be useful in prognosis of node-positive breast cancers.

  8. Evaluation of the systemic antiinflammatory effects of levosimendan in an experimental blunt thoracic trauma model.

    PubMed

    Ateş, Gökay; Yaman, Ferda; Bakar, Bülent; Kısa, Üçler; Atasoy, Pınar; Büyükkoçak, Ünase

    2017-09-01

    Blunt thoracic injury often leads to pulmonary contusion and the development of acute respiratory distress syndrome, which carries a high risk of morbidity and mortality, originating from the local and systemic inflammatory states. This study aimed to investigate the local and systemic antiinflammatory effects of levosimendan in rat models of blunt chest trauma. A total of 32 Wistar albino rats were randomly assigned to one of the following four groups: control, sham, low-dose levosimendan (LDL) (5 µg/kg loading dose for 10 min and 0.05 µg/kg/min intravenous infusion), and high-dose levosimendan (HDL) (10 µg/kg loading dose for 10 min and 0.1 µg/kg/min intravenous infusion). Blunt chest trauma was induced, and after 6 h, the contused pulmonary tissues were histopathologically and immunohistopathologically evaluated, serum TNF-α, IL-1ß, IL-6, and NO levels were biochemically evaluated. The mean arterial pressure was low throughout the experiment in the LDL and HDL groups, with no statistically difference between the groups. Levosimendan reduced the alveolar congestion and hemorrhage, which developed after inducing trauma. Neutrophil infiltration to the damaged pulmonary tissue was also reduced in both the LDL and HDL groups. In rats in which pulmonary contusion (PC) was observed, increased activation of nuclear factor kappa B was observed in the pulmonary tissue, and levosimendan did not reduce this activation. Both high and low doses of levosimendan reduced serum IL-1ß levels, and high doses of levosimendan reduced IL-6 and NO levels. TNF-α levels were not reduced. In conclusion, the results showed that in a rat model of PC, the experimental agent levosimendan could reduce neutrophil cell infiltration to damaged pulmonary tissues and the systemic expressions of some cytokines (IL-1ß, IL-6, and NO), thereby partially reducing and/or correcting pulmonary damage. Systemic inflammatory response that occurs after trauma could also be reduced.

  9. Anti-granuloma activity of Coriandrum sativum in experimental models

    PubMed Central

    Nair, Vinod; Singh, Surender; Gupta, Yogendra Kumar

    2013-01-01

    Background: Coriandrum sativum has been used in the traditional systems of medicine for management of arthritis and other inflammatory disorders. Objectives: In this study, we have evaluated the anti-inflammatory and anti-granuloma activities of Coriandrum sativum hydroalcoholic extract (CSHE) in experimental models. Materials and Methods: The anti-inflammatory activity of CSHE was evaluated using carrageenan-induced paw edema model and the anti-granuloma activity of CSHE was evaluated using the subcutaneous cotton pellet implantation-induced granuloma formation and stimulation of peritoneal macrophages with complete Freund's adjuvant. Serum tumor necrosis factor-α (TNF-α), IL-6, IL-1 β levels, and peritoneal macrophage expression of TNF-R1 were evaluated as markers of global inflammation. Results: CSHE at the highest dose tested (32 mg/kg) produced a significant reduction (P < 0.05) in paw edema after carrageenan administration. CSHE treatment also reduced dry granuloma weight in all treated animals. Serum IL-6 and IL-1 β levels were significantly (P < 0.05) lower in the CSHE (32 mg/kg)-treated group as compared to control. Although there was an increase in serum TNF-α level in the CSHE-treated group as compared to control, TNF-R1 expression on peritoneal macrophages was found to be reduced. Conclusion: Thus, the result of this study demonstrates the anti-inflammatory and anti-granuloma activities of CSHE in experimental models, and validates its traditional use for the management of arthritis and other inflammatory disorders. PMID:23741156

  10. Configuration optimization and experimental accuracy evaluation of a bone-attached, parallel robot for skull surgery.

    PubMed

    Kobler, Jan-Philipp; Nuelle, Kathrin; Lexow, G Jakob; Rau, Thomas S; Majdani, Omid; Kahrs, Lueder A; Kotlarski, Jens; Ortmaier, Tobias

    2016-03-01

    Minimally invasive cochlear implantation is a novel surgical technique which requires highly accurate guidance of a drilling tool along a trajectory from the mastoid surface toward the basal turn of the cochlea. The authors propose a passive, reconfigurable, parallel robot which can be directly attached to bone anchors implanted in a patient's skull, avoiding the need for surgical tracking systems. Prior to clinical trials, methods are necessary to patient specifically optimize the configuration of the mechanism with respect to accuracy and stability. Furthermore, the achievable accuracy has to be determined experimentally. A comprehensive error model of the proposed mechanism is established, taking into account all relevant error sources identified in previous studies. Two optimization criteria to exploit the given task redundancy and reconfigurability of the passive robot are derived from the model. The achievable accuracy of the optimized robot configurations is first estimated with the help of a Monte Carlo simulation approach and finally evaluated in drilling experiments using synthetic temporal bone specimen. Experimental results demonstrate that the bone-attached mechanism exhibits a mean targeting accuracy of [Formula: see text] mm under realistic conditions. A systematic targeting error is observed, which indicates that accurate identification of the passive robot's kinematic parameters could further reduce deviations from planned drill trajectories. The accuracy of the proposed mechanism demonstrates its suitability for minimally invasive cochlear implantation. Future work will focus on further evaluation experiments on temporal bone specimen.

  11. Group virtue: the importance of morality (vs. competence and sociability) in the positive evaluation of in-groups.

    PubMed

    Leach, Colin Wayne; Ellemers, Naomi; Barreto, Manuela

    2007-08-01

    Although previous research has focused on competence and sociability as the characteristics most important to positive group evaluation, the authors suggest that morality is more important. Studies with preexisting and experimentally created in-groups showed that a set of positive traits constituted distinct factors of morality, competence, and sociability. When asked directly, Study 1 participants reported that their in-group's morality was more important than its competence or sociability. An unobtrusive factor analytic method also showed morality to be a more important explanation of positive in-group evaluation than competence or sociability. Experimental manipulations of morality and competence (Study 4) and morality and sociability (Study 5) showed that only in-group morality affected aspects of the group-level self-concept related to positive evaluation (i.e., pride in, or distancing from, the in-group). Consistent with this finding, identification with experimentally created (Study 2b) and preexisting (Studies 4 and 5) in-groups predicted the ascription of morality, but not competence or sociability, to the in-group.

  12. Experimental Evaluation of Unicast and Multicast CoAP Group Communication

    PubMed Central

    Ishaq, Isam; Hoebeke, Jeroen; Moerman, Ingrid; Demeester, Piet

    2016-01-01

    The Internet of Things (IoT) is expanding rapidly to new domains in which embedded devices play a key role and gradually outnumber traditionally-connected devices. These devices are often constrained in their resources and are thus unable to run standard Internet protocols. The Constrained Application Protocol (CoAP) is a new alternative standard protocol that implements the same principals as the Hypertext Transfer Protocol (HTTP), but is tailored towards constrained devices. In many IoT application domains, devices need to be addressed in groups in addition to being addressable individually. Two main approaches are currently being proposed in the IoT community for CoAP-based group communication. The main difference between the two approaches lies in the underlying communication type: multicast versus unicast. In this article, we experimentally evaluate those two approaches using two wireless sensor testbeds and under different test conditions. We highlight the pros and cons of each of them and propose combining these approaches in a hybrid solution to better suit certain use case requirements. Additionally, we provide a solution for multicast-based group membership management using CoAP. PMID:27455262

  13. Analysis and experimental evaluation of a Stewart platform-based force/torque sensor

    NASA Technical Reports Server (NTRS)

    Nguyen, Charles C.; Antrazi, Sami S.

    1992-01-01

    The kinematic analysis and experimentation of a force/torque sensor whose design is based on the mechanism of the Stewart Platform are discussed. Besides being used for measurement of forces/torques, the sensor also serves as a compliant platform which provides passive compliance during a robotic assembly task. It consists of two platforms, the upper compliant platform (UCP) and the lower compliant platform (LCP), coupled together through six spring-loaded pistons whose length variations are measured by six linear voltage differential transformers (LVDT) mounted along the pistons. Solutions to the forward and inverse kinematics of the force sensor are derived. Based on the known spring constant and the piston length changes, forces/torques applied to the LCP gripper are computed using vector algebra. Results of experiments conducted to evaluate the sensing capability of the force sensor are reported and discussed.

  14. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles : Task 4B : material & construction specifications : final report.

    DOT National Transportation Integrated Search

    2015-07-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP composite piles for load-bearing in bridges. This report covers Task 4B, Materials and Construction Specifications. : This technical report...

  15. Scientist impact factor (SIF): a new metric for improving scientists' evaluation?

    PubMed

    Lippi, Giuseppe; Mattiuzzi, Camilla

    2017-08-01

    The publication of scientific research is the mainstay for knowledge dissemination, but is also an essential criterion of scientists' evaluation for recruiting funds and career progression. Although the most widespread approach for evaluating scientists is currently based on the H-index, the total impact factor (IF) and the overall number of citations, these metrics are plagued by some well-known drawbacks. Therefore, with the aim to improve the process of scientists' evaluation, we developed a new and potentially useful indicator of recent scientific output. The new metric scientist impact factor (SIF) was calculated as all citations of articles published in the two years following the publication year of the articles, divided by the overall number of articles published in that year. The metrics was then tested by analyzing data of the 40 top scientists of the local University. No correlation was found between SIF and H-index (r=0.15; P=0.367) or 2 years H-index (r=-0.01; P=0.933), whereas the H-index and 2 years H-index values were found to be highly correlated (r=0.57; P<0.001). A highly significant correlation was also observed between the articles published in one year and the total number of citations to these articles in the two following years (r=0.62; P<0.001). According to our data, the SIF may be a useful measure to complement current metrics for evaluating scientific output. Its use may be especially helpful for young scientists, wherein the SIF reflects the scientific output over the past two years thus increasing their chances to apply to and obtain competitive funding.

  16. Scientist impact factor (SIF): a new metric for improving scientists’ evaluation?

    PubMed Central

    Mattiuzzi, Camilla

    2017-01-01

    Background The publication of scientific research is the mainstay for knowledge dissemination, but is also an essential criterion of scientists’ evaluation for recruiting funds and career progression. Although the most widespread approach for evaluating scientists is currently based on the H-index, the total impact factor (IF) and the overall number of citations, these metrics are plagued by some well-known drawbacks. Therefore, with the aim to improve the process of scientists’ evaluation, we developed a new and potentially useful indicator of recent scientific output. Methods The new metric scientist impact factor (SIF) was calculated as all citations of articles published in the two years following the publication year of the articles, divided by the overall number of articles published in that year. The metrics was then tested by analyzing data of the 40 top scientists of the local University. Results No correlation was found between SIF and H-index (r=0.15; P=0.367) or 2 years H-index (r=−0.01; P=0.933), whereas the H-index and 2 years H-index values were found to be highly correlated (r=0.57; P<0.001). A highly significant correlation was also observed between the articles published in one year and the total number of citations to these articles in the two following years (r=0.62; P<0.001). Conclusions According to our data, the SIF may be a useful measure to complement current metrics for evaluating scientific output. Its use may be especially helpful for young scientists, wherein the SIF reflects the scientific output over the past two years thus increasing their chances to apply to and obtain competitive funding. PMID:28856143

  17. Digital simulation and experimental evaluation of the CO2-H(plus) control of pulmonary ventilation

    NASA Technical Reports Server (NTRS)

    Milhorn, H. T., Jr.; Reynolds, W. J.

    1972-01-01

    Previous models of the CO2-H(+) control of ventilation have been concerned either with the response to CO2 inhalation, or the response to perfusion of the surface of the medulla with mock cerebrospinal fluid having a high P sub CO2. Simulation of both responses with the same model has not been attempted. The purpose of the present study was two fold; first to develop such a model and, second, to obtain experimental data from human subjects for both developing this model and for evaluating this and future models.

  18. Experimental evaluation and design of unfilled and concrete-filled FRP composite piles, task 6 - FRP composite pile axial compression testing.

    DOT National Transportation Integrated Search

    2015-04-01

    The overall goal of this project is the experimental evaluation and design of unfilled and concrete-filled FRP : composite piles for load-bearing in bridges. This report covers Task 6, FRP Composite Pile Axial Compression : Testing. : Hollow and conc...

  19. Assessment of Factors Resulting in Abuse Evaluations in Young Children with Minor Head Trauma

    ERIC Educational Resources Information Center

    Anderst, James D.

    2008-01-01

    Objective: The primary objective was to determine which of the examined factors prompted physicians to initiate a further abuse evaluation in young children with minor head injury. The recording of important historical elements in the charts of these patients was also evaluated. Methods: Charts of 349 children less than 3 years of age with minor…

  20. National Patterns of Urethral Evaluation and Risk Factors for Urethral Injury in Patients With Penile Fracture.

    PubMed

    Pariser, Joseph J; Pearce, Shane M; Patel, Sanjay G; Bales, Gregory T

    2015-07-01

    To examine the epidemiology and timing of penile fracture, patterns of urethral evaluation, and risk factors for concomitant urethral injury. The National Inpatient Sample (2003-2011) was used to identify patients with penile fractures. Clinical data included age, race, comorbidity, insurance, hospital factors, timing, hematuria, and urinary symptoms. Rates of formal urethral evaluation (cystoscopy or urethrogram) and urethral injury were calculated. Multivariate logistic regression was used to identify predictors of urethral evaluation and risk factors for urethral injury. A weighted population of 3883 patients with penile fracture was identified. Presentations during weekends (37%) and summers (30%) were overrepresented (both P <.001). Urethral evaluation was performed in 882 patients (23%). Urethral injury was diagnosed in 813 patients (21%) with penile fracture. There was an increased odds of urethral evaluation with hematuria (odds ratio [OR] = 2.99; 95% confidence interval [CI], 1.03-8.73; P = .045) and a decrease for Hispanics (OR = 0.42; 95% CI, 0.22-0.82; P = .011). Older age (32-41 years: OR = 1.84; 95% CI, 1.07-3.16; P = .027; >41 years: OR = 2.25; 95% CI, 1.25-4.05; P = .007), black race (OR = 1.93; 95% CI, 1.12-3.34; P = .018), and hematuria (OR = 17.03; 95% CI, 3.20-90.54; P = .001) were independent risk factors for urethral injury. Penile fractures, which occur disproportionately during summer and weekends, were associated with a 21% risk of urethral injury. Urethral evaluations were performed in a minority of patients. Even in patients with hematuria, 55% of patients underwent formal urethral evaluation. On multivariate analysis of patients with penile fracture, hematuria as well as older age and black race were independently associated with concomitant urethral injury. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Factor selection for service quality evaluation: a hospital case study.

    PubMed

    Ameryoun, Ahmad; Najafi, Seyedvahid; Nejati-Zarnaqi, Bayram; Khalilifar, Seyed Omid; Ajam, Mahdi; Ansarimoghadam, Ahmad

    2017-02-13

    Purpose The purpose of this paper is to develop a systematic approach to predict service quality dimension's influence on service quality using a novel analysis based on data envelopment and SERVQUAL. Design/methodology/approach To assess hospital service quality in Tehran, expectation and perception of those who received the services were evaluated using SERVQUAL. The hospital service quality dimensions were found by exploratory factor analysis (EFA). To compare customer expectation and perception, perceived service quality index (PSQI) was measured using a new method based on common weights. A novel sensitivity approach was used to test the service quality factor's impact on the PSQI. Findings A new service quality dimension named "trust in services" was found using EFA, which is not an original SERVQUAL factor. The approach was applied to assess the hospital's service quality. Since the PSQI value was 0.76 it showed that improvements are needed to meet customer expectations. The results showed the factor order that affect PSQI. "Trust in services" has the strongest influence on PSQI followed by "tangibles," "assurance," "empathy," and "responsiveness," respectively. Practical implications This work gives managers insight into service quality by following a systematic method; i.e., measuring perceived service quality from the customer viewpoint and service factors' impact on customer perception. Originality/value The procedure helps managers to select the required service quality dimensions which need improvement and predict their effects on customer perception.

  2. Post-Flight Back Pain Following International Space Station Missions: Evaluation of Spaceflight Risk Factors

    NASA Technical Reports Server (NTRS)

    Laughlin, M. S.; Murray, J. D.; Wear, M. L.; Van Baalen, M.

    2016-01-01

    INTRODUCTION Back pain during spaceflight has often been attributed to the lengthening of the spinal column due to the absence of gravity during both short and long-duration missions. Upon landing and re-adaptation to gravity, the spinal column reverts back to its original length thereby causing some individuals to experience pain and muscular spasms, while others experience no ill effects. With International Space Station (ISS) missions, cases of back pain and injury are more common post-flight, but little is known about the potential risk factors. Thus, the purpose of this project was to perform an initial evaluation of reported post-flight back pain and injury cases to relevant spaceflight risk factors in United States astronauts that have completed an ISS mission. METHODS All US astronauts who completed an ISS mission between Expeditions (EXP) 1 and 41 (2000-2015) were included in this evaluation. Forty-five astronauts (36 males and 9 females) completed 50 ISS missions during the study time period, as 5 astronauts completed 2 ISS missions. Researchers queried medical records of the 45 astronauts for occurrences of back pain and injury. A case was defined as any reported event of back pain or injury to the cervical, thoracic, lumbar, sacral, or coccyx spine regions. Data sources for the cases included the Flight Medicine Clinic's electronic medical record; Astronaut Strength, Conditioning and Rehabilitation electronic documentation; the Private Medical Conference tool; and the Space Medicine Operations Team records. Post-flight cases were classified as an early case if reported within 45 days of landing (R + 45) or a late case if reported from R + 46 to R + 365 days after landing (R + 1y). Risk factors in the astronaut population for back pain include age, sex, prior military service, and prior history of back pain. Additionally, spaceflight specific risk factors such as type of landing vehicle and onboard exercise countermeasures were included to evaluate their

  3. A quasi-experimental evaluation of a school-based intervention for children experiencing family disruption.

    PubMed

    Abel, Eileen Mazur; Chung-Canine, Unju; Broussard, Karen

    2013-01-01

    Despite the fact that children are negatively impacted by family separation and divorce (Amato, 2001 ; Dreman & Shemi, 2004 ; Kelly, 2000 ) there is a paucity of information regarding evidence-based social work practice with children coping with family disruption. In order to address this gap, the authors describe the process and outcomes of a quasi-experimental evaluation (N = 79) designed to reduce the behavioral, emotional, and academic problems that children often face when experiencing divorce or parental separation. Results of data analysis (paired t-tests, independent t-tests, and analysis of variance) suggest (p < .05) that the intervention is effective in helping children cope with family disruption.

  4. NATURAL GAS VARIABILITY IN CALIFORNIA: ENVIRONMENTAL IMPACTS AND DEVICE PERFORMANCE EXPERIMENTAL EVALUATION OF POLLUTANT EMISSIONS FROM RESIDENTIAL APPLIANCES

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

    Singer, Brett C.; Apte, Michael G.; Black, Douglas R.

    2009-12-01

    The effect of liquefied natural gas on pollutant emissions was evaluated experimentally with used and new appliances in the laboratory and with appliances installed in residences, targeting information gaps from previous studies. Burner selection targeted available technologies that are projected to comprise the majority of installed appliances over the next decade. Experiments were conducted on 13 cooktop sets, 12 ovens, 5 broiler burners, 5 storage water heaters, 4 forced air furnaces, 1 wall furnace, and 6 tankless water heaters. Air-free concentrations and fuel-based emission factors were determined for carbon monoxide, nitrogen oxides, nitrogen dioxide, and the number of (predominantly ultrafine)more » particles over complete burns?including transient effects (device warm-up and intermittent firing of burners) following ignition--and during more stable end-of-burn conditions. Formaldehyde was measured over multi-burn cycles. The baseline fuel was Northern California line gas with Wobbe number (a measure of fuel energy delivery rate) of 1320-1340; test fuels had Wobbe numbers of roughly 1390 and 1420, and in some cases 1360. No ignition or operational problems were observed during test fuel use. Baseline emissions varied widely across and within burner groups and with burner operational mode. Statistically significant emissions changes were observed for some pollutants on some burners.« less

  5. Evaluation of phenyl-propanedione on yellowing and chemical-mechanical properties of experimental dental resin-based materials.

    PubMed

    Oliveira, Dayane Carvalho Ramos Salles de; Souza-Junior, Eduardo José; Dobson, Adam; Correr, Ana Rosa Costa; Brandt, William Cunha; Sinhoreti, Mário Alexandre Coelho

    2016-01-01

    To evaluate the influence of phenyl-propanedione on yellowing and chemical-mechanical properties of experimental resin-based materials photoactivated using different light curing units (LCUs). Experimental resin-based materials with the same organic matrix (60:40 wt% BisGMA:TEGDMA) were mechanically blended using a centrifugal mixing device. To this blend, different photoinitiator systems were added in equimolar concentrations with aliphatic amine doubled by wt%: 0.4 wt% CQ; 0.38 wt% PPD; or 0.2 wt% CQ and 0.19 wt% PPD. The degree of conversion (DC), flexural strength (FS), Young's modulus (YM), Knoop hardness (KNH), crosslinking density (CLD), and yellowing (Y) were evaluated (n=10). All samples were light cured with the following LCUs: a halogen lamp (XL 2500), a monowave LED (Radii), or a polywave LED (Valo) with 16 J/cm2. The results were analysed by two-way ANOVA and Tukey's test (α=0.05). No statistical differences were found between the different photoinitiator systems to KNH, CLS, FS, and YM properties (p≥0.05). PPD/CQ association showed the higher DC values compared with CQ and PPD isolated systems when photoactivated by a polywave LED (p≤0.05). Y values were highest for the CQ compared with the PPD systems (p≤0.05). PPD isolated system promoted similar chemical and mechanical properties and less yellowing compared with the CQ isolated system, regardless of the LCU used.

  6. An Evaluation of a Shared Leadership Training Program

    ERIC Educational Resources Information Center

    Allen, Lavonda Ann

    2010-01-01

    The purpose of the quantitative quasi-experimental equivalent time series study was to evaluate the effectiveness of a work based shared leadership training program in a less than 200 bed hospital in rural, south-central United States. Nursing shortages and the current emphasis on quality are factors that make recruitment and retention of nurses…

  7. Evaluating abdominal oedema during experimental sepsis using an isotope technique.

    PubMed

    Lattuada, Marco; Maripuu, Enn; Segerstad, Carl Hard af; Lundqvist, Hans; Hedenstierna, Göran

    2012-05-01

    Abdominal oedema is common in sepsis. A technique for the study of such oedema may guide in the fluid regime of these patients. We modified a double-isotope technique to evaluate abdominal organ oedema and fluid extravasation in 24 healthy or endotoxin-exposed ('septic') piglets. Two different markers were used: red blood cells (RBC) labelled with Technetium-99m ((99m)Tc) and Transferrin labelled with Indium111 ((111)In). Images were acquired on a dual-head gamma camera. Microscopic evaluation of tissue biopsies was performed to compare data with the isotope technique. No (99m)Tc activity was measured in the plasma fraction in blood sampled after labelling. Similarly, after molecular size gel chromatography, (111)In activity was exclusively found in the high molecular fraction of the plasma. Extravasation of transferrin, indicating the degree of abdominal oedema, was 4·06 times higher in the LPS group compared to the healthy controls (P<0·0001). Abdominal free fluid, studied in 3 animals, had as high (111)In activity as in plasma, but no (99m)Tc activity. Intestinal lymphatic vessel size was higher in LPS (3·7 ± 1·1 μm) compared to control animals (0·6 + 0·2 μm; P<0·001) and oedema correlated to villus diameter (R(2) = 0·918) and lymphatic diameter (R(2) = 0·758). A correlation between a normalized index of oedema formation (NI) and intra-abdominal pressure (IAP) was also found: NI = 0·46*IAP-3·3 (R(2) = 0·56). The technique enables almost continuous recording of abdominal oedema formation and may be a valuable tool in experimental research, with the potential to be applied in the clinic. © 2011 The Authors. Clinical Physiology and Functional Imaging © 2011 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

  8. Evaluation of transverse dispersion effects in tank experiments by numerical modeling: parameter estimation, sensitivity analysis and revision of experimental design.

    PubMed

    Ballarini, E; Bauer, S; Eberhardt, C; Beyer, C

    2012-06-01

    Transverse dispersion represents an important mixing process for transport of contaminants in groundwater and constitutes an essential prerequisite for geochemical and biodegradation reactions. Within this context, this work describes the detailed numerical simulation of highly controlled laboratory experiments using uranine, bromide and oxygen depleted water as conservative tracers for the quantification of transverse mixing in porous media. Synthetic numerical experiments reproducing an existing laboratory experimental set-up of quasi two-dimensional flow through tank were performed to assess the applicability of an analytical solution of the 2D advection-dispersion equation for the estimation of transverse dispersivity as fitting parameter. The fitted dispersivities were compared to the "true" values introduced in the numerical simulations and the associated error could be precisely estimated. A sensitivity analysis was performed on the experimental set-up in order to evaluate the sensitivities of the measurements taken at the tank experiment on the individual hydraulic and transport parameters. From the results, an improved experimental set-up as well as a numerical evaluation procedure could be developed, which allow for a precise and reliable determination of dispersivities. The improved tank set-up was used for new laboratory experiments, performed at advective velocities of 4.9 m d(-1) and 10.5 m d(-1). Numerical evaluation of these experiments yielded a unique and reliable parameter set, which closely fits the measured tracer concentration data. For the porous medium with a grain size of 0.25-0.30 mm, the fitted longitudinal and transverse dispersivities were 3.49×10(-4) m and 1.48×10(-5) m, respectively. The procedures developed in this paper for the synthetic and rigorous design and evaluation of the experiments can be generalized and transferred to comparable applications. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Performance Evaluation of Large Aperture 'Polished Panel' Optical Receivers Based on Experimental Data

    NASA Technical Reports Server (NTRS)

    Vilnrotter, Victor

    2013-01-01

    Recent interest in hybrid RF/Optical communications has led to the development and installation of a "polished-panel" optical receiver evaluation assembly on the 34-meter research antenna at Deep-Space Station 13 (DSS-13) at NASA's Goldstone Communications Complex. The test setup consists of a custom aluminum panel polished to optical smoothness, and a large-sensor CCD camera designed to image the point-spread function (PSF) generated by the polished aluminum panel. Extensive data has been obtained via realtime tracking and imaging of planets and stars at DSS-13. Both "on-source" and "off-source" data were recorded at various elevations, enabling the development of realistic simulations and analytic models to help determine the performance of future deep-space communications systems operating with on-off keying (OOK) or pulse-position-modulated (PPM) signaling formats with photon-counting detection, and compared with the ultimate quantum bound on detection performance for these modulations. Experimentally determined PSFs were scaled to provide realistic signal-distributions across a photon-counting detector array when a pulse is received, and uncoded as well as block-coded performance analyzed and evaluated for a well-known class of block codes.

  10. A comprehensive evaluation of the toxicology of experimental cigarettes manufactured with banded papers.

    PubMed

    Werley, Michael S; Jerome, Ann M; DeSoi, Darren J; Coggins, Christopher R E; Oldham, Michael J; McKinney, Willie J

    2013-01-01

    To comply with state requirements, cigarette manufacturers have added low-permeability bands to the cigarette paper. These bands can extinguish the cigarette when it is no longer being puffed by a smoker. This study was conducted to evaluate the toxicology resulting from the addition of different types of bands to experimental cigarettes. A battery of assays that are typically used in toxicology studies with cigarette smoke, namely smoke chemistry, in vitro mutagenicity and cytotoxicity, and inhalation studies with rats, were used to evaluate different band characteristics added to cigarette paper. Although differences in the amount of band material was associated with an increase in some metals measured in mainstream tobacco smoke, it was not dose responsive to any band design parameter (base paper permeability, band width, band spacing, band chalk amount, or citrate). Occasional, minor differences were produced by the different types of bands; overall, there was no increased toxicity. Although there were increases and decreases in some mainstream smoke constituents, the in vitro and in vivo testing performed demonstrated that low-permeability bands on cigarettes do not modify the toxicity of smoke inhaled by smokers.

  11. Small form factor optical fiber connector evaluation for harsh environments

    NASA Astrophysics Data System (ADS)

    Ott, Melanie N.; Thomes, W. Joe, Jr.; Chuska, Richard F.; Switzer, Robert; Blair, Diana E.

    2011-09-01

    For the past decade NASA programs have utilized the Diamond AVIM connector for optical fiber assemblies on space flight instrumentation. These connectors have been used in communications, sensing and LIDAR systems where repeatability and high performance are required. Recently Diamond has released a smaller form factor optical fiber connector called the "Mini-AVIM" which although more compact still includes the tight tolerances and the ratcheting feature of the heritage AVIM. NASA Goddard Space Flight Center Photonics Group in the Parts, Packaging and Assembly Technologies Office has been performing evaluations of this connector to determine how it compares to the performance of the AVIM connector and to assess its feasibility for harsh environmental applications. Vibration and thermal testing were performed on the Mini-AVIM with both multi-mode and single-mode optical fiber using insitu optical transmission monitoring. Random vibration testing was performed using typical launch condition profiles for most NASA missions but extended to 35 Grms, which is much higher than most requirements. Thermal testing was performed incrementally up to a range of -55°C to +125°C. The test results include both unjacketed fiber and cabled assembly evaluations. The data presented here indicate that the Mini-AVIM provides a viable option for small form factor applications that require a high performance optical fiber connector.

  12. Evaluation of the Risk Factors for a Rotator Cuff Retear After Repair Surgery.

    PubMed

    Lee, Yeong Seok; Jeong, Jeung Yeol; Park, Chan-Deok; Kang, Seung Gyoon; Yoo, Jae Chul

    2017-07-01

    A retear is a significant clinical problem after rotator cuff repair. However, no study has evaluated the retear rate with regard to the extent of footprint coverage. To evaluate the preoperative and intraoperative factors for a retear after rotator cuff repair, and to confirm the relationship with the extent of footprint coverage. Cohort study; Level of evidence, 3. Data were retrospectively collected from 693 patients who underwent arthroscopic rotator cuff repair between January 2006 and December 2014. All repairs were classified into 4 types of completeness of repair according to the amount of footprint coverage at the end of surgery. All patients underwent magnetic resonance imaging (MRI) after a mean postoperative duration of 5.4 months. Preoperative demographic data, functional scores, range of motion, and global fatty degeneration on preoperative MRI and intraoperative variables including the tear size, completeness of rotator cuff repair, concomitant subscapularis repair, number of suture anchors used, repair technique (single-row or transosseous-equivalent double-row repair), and surgical duration were evaluated. Furthermore, the factors associated with failure using the single-row technique and transosseous-equivalent double-row technique were analyzed separately. The retear rate was 7.22%. Univariate analysis revealed that rotator cuff retears were affected by age; the presence of inflammatory arthritis; the completeness of rotator cuff repair; the initial tear size; the number of suture anchors; mean operative time; functional visual analog scale scores; Simple Shoulder Test findings; American Shoulder and Elbow Surgeons scores; and fatty degeneration of the supraspinatus, infraspinatus, and subscapularis. Multivariate logistic regression analysis revealed patient age, initial tear size, and fatty degeneration of the supraspinatus as independent risk factors for a rotator cuff retear. Multivariate logistic regression analysis of the single-row group

  13. Participatory ergonomics for psychological factors evaluation in work system design.

    PubMed

    Wang, Lingyan; Lau, Henry Y K

    2012-01-01

    It is a well recognized understanding that workers whose voice needs to be heard should be actively encouraged as full participants and involved in the early design stages of new ergonomic work system which encompass the development and implementation of new tools, workplaces, technologies or organizations. This paper presents a novel participatory strategy to evaluate three key psychological factors which are respectively mental fatigue, spiritual stress, and emotional satisfaction in work system design based on a modified version of Participatory Ergonomics (PE). In specific, it integrates a PE technique with a formulation view by combining the parallel development of PE strategies, frameworks and functions throughout the coverage of the entire work system design process, so as to bridge the gap between qualitative and quantitative analysis of psychological factors which can cause adverse or advantageous effects on worker's physiological and behavioral performance.

  14. Empirical evaluation of humpback whale telomere length estimates; quality control and factors causing variability in the singleplex and multiplex qPCR methods

    PubMed Central

    2012-01-01

    Background Telomeres, the protective cap of chromosomes, have emerged as powerful markers of biological age and life history in model and non-model species. The qPCR method for telomere length estimation is one of the most common methods for telomere length estimation, but has received recent critique for being too error-prone and yielding unreliable results. This critique coincides with an increasing awareness of the potentials and limitations of the qPCR technique in general and the proposal of a general set of guidelines (MIQE) for standardization of experimental, analytical, and reporting steps of qPCR. In order to evaluate the utility of the qPCR method for telomere length estimation in non-model species, we carried out four different qPCR assays directed at humpback whale telomeres, and subsequently performed a rigorous quality control to evaluate the performance of each assay. Results Performance differed substantially among assays and only one assay was found useful for telomere length estimation in humpback whales. The most notable factors causing these inter-assay differences were primer design and choice of using singleplex or multiplex assays. Inferred amplification efficiencies differed by up to 40% depending on assay and quantification method, however this variation only affected telomere length estimates in the worst performing assays. Conclusion Our results suggest that seemingly well performing qPCR assays may contain biases that will only be detected by extensive quality control. Moreover, we show that the qPCR method for telomere length estimation can be highly precise and accurate, and thus suitable for telomere measurement in non-model species, if effort is devoted to optimization at all experimental and analytical steps. We conclude by highlighting a set of quality controls which may serve for further standardization of the qPCR method for telomere length estimation, and discuss some of the factors that may cause variation in qPCR experiments

  15. A Quasi-Experimental Evaluation of a Community-Based HIV Prevention Intervention for Mexican American Female Adolescents: The SHERO's Program

    ERIC Educational Resources Information Center

    Harper, Gary W.; Bangi, Audrey K.; Sanchez, Bernadette; Doll, Mimi; Pedraza, Ana

    2009-01-01

    This article describes a quasi-experimental evaluation of a community-based, culturally and ecologically tailored HIV prevention intervention for Mexican American female adolescents grounded in the AIDS risk reduction model. A total of 378 Mexican American female adolescents (mean age = 15.2) participated in either the nine-session SHERO's (a…

  16. Experimental investigations of pupil accommodation factors.

    PubMed

    Lee, Eui Chul; Lee, Ji Woo; Park, Kang Ryoung

    2011-08-17

    PURPOSE. The contraction and dilation of the iris muscle that controls the amount of light entering the retina causes pupil accommodation. In this study, experiments were performed and two of the three factors that influence pupil accommodation were analyzed: lighting conditions and depth fixations. The psychological benefits were not examined, because they could not be quantified. METHODS. A head-wearable eyeglasses-based, eye-capturing device was designed to measure pupil size. It included a near-infrared (NIR) camera and an NIR light-emitting diode. Twenty-four subjects watched two-dimensional (2D) and three-dimensional (3D) stereoscopic videos of the same content, and the changes in pupil size were measured by using the eye-capturing device and image-processing methods: RESULTS. The pupil size changed with the intensity of the videos and the disparities between the left and right images of a 3D stereoscopic video. There was correlation between the pupil size and average intensity. The pupil diameter could be estimated as being contracted from approximately 5.96 to 4.25 mm as the intensity varied from 0 to 255. Further, from the changes in the depth fixation for the pupil accommodation, it was confirmed that the depth fixation also affected accommodation of pupil size. CONCLUSIONS. It was confirmed that the lighting condition was an even more significant factor in pupil accommodation than was depth fixation (significance ratio: approximately 3.2:1) when watching 3D stereoscopic video. Pupil accommodation was more affected by depth fixation in the real world than was the binocular convergence in the 3D stereoscopic display.

  17. Evaluation of thromboelastography in two factor XII-deficient cats.

    PubMed

    Blois, Shauna L; Holowaychuk, Marie K; Wood, R Darren

    2015-01-01

    The current report describes thromboelastography (TEG) findings in two cats with factor XII (FXII) deficiency. The first cat was diagnosed with bilateral perinephric pseudocysts; hemostatic testing was performed prior to performing renal aspirates. The second cat was healthy; hemostatic testing was performed prior to inclusion into a research project. Both cats had markedly prolonged partial thromboplastin times and hypocoagulable TEG tracings when samples were activated with kaolin. However, when tissue factor (TF) was used to activate the sample, both cats had normal-to-hypercoagulable TEG tracings. The cats each had a subnormal FXII level. TEG is becoming widely used to investigate hemostasis in veterinary patients, and TEG results in cats with FXII deficiency have not been previously reported. FXII deficiency is the most common hereditary hemostatic defect in cats. While FXII deficiency does not lead to in vivo hemorrhagic tendencies, it can lead to marked prolongation in activated partial thromboplastin and activated clotting times, and cannot be differentiated from true hemorrhagic diatheses without measuring individual factor activity. With the increased use of TEG to evaluate hemostasis in veterinary patients, it is important to recognize the effects of FXII deficiency on this testing modality. The finding of a hypocoagulable kaolin-activated TEG tracing and a concurrent normal TF-activated TEG tracing in samples should prompt clinicians to consider ruling out FXII deficiency.

  18. Evaluation of thromboelastography in two factor XII-deficient cats

    PubMed Central

    Holowaychuk, Marie K; Wood, R Darren

    2015-01-01

    Case summary The current report describes thromboelastography (TEG) findings in two cats with factor XII (FXII) deficiency. The first cat was diagnosed with bilateral perinephric pseudocysts; hemostatic testing was performed prior to performing renal aspirates. The second cat was healthy; hemostatic testing was performed prior to inclusion into a research project. Both cats had markedly prolonged partial thromboplastin times and hypocoagulable TEG tracings when samples were activated with kaolin. However, when tissue factor (TF) was used to activate the sample, both cats had normal-to-hypercoagulable TEG tracings. The cats each had a subnormal FXII level. Relevance and novel information TEG is becoming widely used to investigate hemostasis in veterinary patients, and TEG results in cats with FXII deficiency have not been previously reported. FXII deficiency is the most common hereditary hemostatic defect in cats. While FXII deficiency does not lead to in vivo hemorrhagic tendencies, it can lead to marked prolongation in activated partial thromboplastin and activated clotting times, and cannot be differentiated from true hemorrhagic diatheses without measuring individual factor activity. With the increased use of TEG to evaluate hemostasis in veterinary patients, it is important to recognize the effects of FXII deficiency on this testing modality. The finding of a hypocoagulable kaolin-activated TEG tracing and a concurrent normal TF-activated TEG tracing in samples should prompt clinicians to consider ruling out FXII deficiency. PMID:28491358

  19. Global Mapping of Transcription Factor Binding Sites by Sequencing Chromatin Surrogates: a Perspective on Experimental Design, Data Analysis, and Open Problems.

    PubMed

    Wei, Yingying; Wu, George; Ji, Hongkai

    2013-05-01

    Mapping genome-wide binding sites of all transcription factors (TFs) in all biological contexts is a critical step toward understanding gene regulation. The state-of-the-art technologies for mapping transcription factor binding sites (TFBSs) couple chromatin immunoprecipitation (ChIP) with high-throughput sequencing (ChIP-seq) or tiling array hybridization (ChIP-chip). These technologies have limitations: they are low-throughput with respect to surveying many TFs. Recent advances in genome-wide chromatin profiling, including development of technologies such as DNase-seq, FAIRE-seq and ChIP-seq for histone modifications, make it possible to predict in vivo TFBSs by analyzing chromatin features at computationally determined DNA motif sites. This promising new approach may allow researchers to monitor the genome-wide binding sites of many TFs simultaneously. In this article, we discuss various experimental design and data analysis issues that arise when applying this approach. Through a systematic analysis of the data from the Encyclopedia Of DNA Elements (ENCODE) project, we compare the predictive power of individual and combinations of chromatin marks using supervised and unsupervised learning methods, and evaluate the value of integrating information from public ChIP and gene expression data. We also highlight the challenges and opportunities for developing novel analytical methods, such as resolving the one-motif-multiple-TF ambiguity and distinguishing functional and non-functional TF binding targets from the predicted binding sites. The online version of this article (doi:10.1007/s12561-012-9066-5) contains supplementary material, which is available to authorized users.

  20. Evaluation of factors affecting the edge formability of two hot rolled multiphase steels

    NASA Astrophysics Data System (ADS)

    Mukherjee, Monideepa; Tiwari, Sumit; Bhattacharya, Basudev

    2018-02-01

    In this study, the effect of various factors on the hole expansion ratio and hence on the edge formability of two hot rolled multiphase steels, one with a ferrite-martensite microstructure and the other with a ferrite-bainite microstructure, was investigated through systematic microstructural and mechanical characterization. The study revealed that the microstructure of the steels, which determines their strain hardening capacity and fracture resistance, is the principal factor controlling edge formability. The influence of other factors such as tensile strength, ductility, anisotropy, and thickness, though present, are secondary. A critical evaluation of the available empirical models for hole expansion ratio prediction is also presented.

  1. Experimental investigation of the mass flow gain factor in a draft tube with cavitation vortex rope

    NASA Astrophysics Data System (ADS)

    Landry, C.; Favrel, A.; Müller, A.; Yamamoto, K.; Alligné, S.; Avellan, F.

    2017-04-01

    At off-design operating operations, cavitating flow is often observed in hydraulic machines. The presence of a cavitation vortex rope may induce draft tube surge and electrical power swings at part load and full load operations. The stability analysis of these operating conditions requires a numerical pipe model taking into account the complexity of the two-phase flow. Among the hydroacoustic parameters describing the cavitating draft tube flow in the numerical model, the mass flow gain factor, representing the mass excitation source expressed as the rate of change of the cavitation volume as a function of the discharge, remains difficult to model. This paper presents a quasi-static method to estimate the mass flow gain factor in the draft tube for a given cavitation vortex rope volume in the case of a reduced scale physical model of a ν = 0.27 Francis turbine. The methodology is based on an experimental identification of the natural frequency of the test rig hydraulic system for different Thoma numbers. With the identification of the natural frequency, it is possible to model the wave speed, the cavitation compliance and the volume of the cavitation vortex rope. By applying this new methodology for different discharge values, it becomes possible to identify the mass flow gain factor and improve the accuracy of the system stability analysis.

  2. Efficacy of recombinant bovine epidermal growth factor in the treatment of experimental subclinical Staphylococcus aureus mastitis in a ewe model.

    PubMed

    Gabadage, Kamal; Chirino-Trejo, Manuel; Campbell, John; Luby, Christopher

    2017-01-01

    Staphylococcus aureus is the most common contagious mastitis pathogen of dairy cattle. Antimicrobial treatment of infected cattle results in variable cure rates. Epidermal growth factor (EGF) plays an important role in the modulation of host innate immune responses and the regulation of mammary epithelial regeneration, indicating that EGF may be useful as a treatment for mastitis. A pilot study was conducted to evaluate the efficacy of recombinant bovine EGF (rbEGF) for the treatment of S aureus intramammary infection (IMI) using an ovine model. Each ewe was experimentally infected with S aureus in both udder halves. One udder half of each ewe received one of two treatments: EGF (n=13) or pirlimycin (n=13). The contralateral udder half of each ewe received sterile saline as a control. The bacteriological cure rate following rbEGF was significantly lower (15 per cent) than that attained with pirlimycin hydrochloride (61 per cent) and did not differ from that following treatment with sterile saline. Cure rates following treatment with rbEGF were not significantly different to those following sterile saline. Given that EGF is associated with modulation of host immunity and wound healing, future studies into EGF should not focus on whether EGF increases cure rates of S aureus IMI.

  3. Food advertising, children's food choices and obesity: interplay of cognitive defences and product evaluation: an experimental study.

    PubMed

    Tarabashkina, L; Quester, P; Crouch, R

    2016-04-01

    To investigate the role of product evaluations, nutritional and persuasion knowledge on children's food choices conducted because of limited evidence about the role of product evaluations on consumer choices in conjunction with cognitive defences. A randomised controlled 2 × 2 factorial experiment with an exposure to a food and a control (toy) advertisement conducted in a non-laboratory setting at an annual event traditionally visited by families. Children aged 7-13 years with biometric/weight data representative of the general Australian population. Height and weight (converted into body mass index z-scores) measured in addition to children's nutritional and persuasion knowledge, product evaluations, age and gender. The factors that undermine children's cognitive defences relate to taste, social appeal of foods and low nutritional and persuasion knowledge. An interplay between the above-mentioned factors was also observed, identifying four groups among young consumers, alluding to a complex and at times impulsive nature of children's decisions: (1) knowledgeable children with less positive product evaluations choosing a healthy snack; (2) knowledgeable but hedonism-oriented children seeking peer conformity choosing an advertised product; (3) knowledgeable children who chose a snack belonging to the same product category; and (4) less knowledgeable children with positive product evaluations and low nutritional knowledge choosing snacks from the advertised product category. Obese children were more likely to belong to a cluster of less knowledgeable and hedonism-oriented children. The problem of consumption of less healthy foods is complex and multiple factors need to be considered by health practitioners, social marketers and parents to address the issue of childhood obesity. Nutritional knowledge alone is not sufficient to ensure children make healthier food choices and emphasis should also be placed on persuasion knowledge education, targeting of peer norms

  4. Experimental investigation of factors affecting the absolute recovery coefficients in iodine-124 PET lesion imaging

    NASA Astrophysics Data System (ADS)

    Jentzen, Walter

    2010-04-01

    The use of recovery coefficients (RCs) in 124I PET lesion imaging is a simple method to correct the imaged activity concentration (AC) primarily for the partial-volume effect and, to a minor extent, for the prompt gamma coincidence effect. The aim of this phantom study was to experimentally investigate a number of various factors affecting the 124I RCs. Three RC-based correction approaches were considered. These approaches differ with respect to the volume of interest (VOI) drawn, which determines the imaged AC and the RCs: a single voxel VOI containing the maximum value (maximum RC), a spherical VOI with a diameter of the scanner resolution (resolution RC) and a VOI equaling the physical object volume (isovolume RC). Measurements were performed using mainly a stand-alone PET scanner (EXACT HR+) and a latest-generation PET/CT scanner (BIOGRAPH mCT). The RCs were determined using a cylindrical phantom containing spheres or rotational ellipsoids and were derived from images acquired with a reference acquisition protocol. For each type of RC, the influence of the following factors on the RC was assessed: object shape, background activity spill in and iterative image reconstruction parameters. To evaluate the robustness of the RC-based correction approaches, the percentage deviation between RC-corrected and true ACs was determined from images acquired with a clinical acquisition protocol of different AC regimes. The observed results of the shape and spill-in effects were compared with simulation data derived from a convolution-based model. The study demonstrated that the shape effect was negligible and, therefore, was in agreement with theoretical expectations. In contradiction to the simulation results, the observed spill-in effect was unexpectedly small. To avoid variations in the determination of RCs due to reconstruction parameter changes, image reconstruction with a pixel length of about one-third or less of the scanner resolution and an OSEM 1 × 32 algorithm or

  5. Experimental evaluation of model predictive control and inverse dynamics control for spacecraft proximity and docking maneuvers

    NASA Astrophysics Data System (ADS)

    Virgili-Llop, Josep; Zagaris, Costantinos; Park, Hyeongjun; Zappulla, Richard; Romano, Marcello

    2018-03-01

    An experimental campaign has been conducted to evaluate the performance of two different guidance and control algorithms on a multi-constrained docking maneuver. The evaluated algorithms are model predictive control (MPC) and inverse dynamics in the virtual domain (IDVD). A linear-quadratic approach with a quadratic programming solver is used for the MPC approach. A nonconvex optimization problem results from the IDVD approach, and a nonlinear programming solver is used. The docking scenario is constrained by the presence of a keep-out zone, an entry cone, and by the chaser's maximum actuation level. The performance metrics for the experiments and numerical simulations include the required control effort and time to dock. The experiments have been conducted in a ground-based air-bearing test bed, using spacecraft simulators that float over a granite table.

  6. An Experimental Evaluation of the Performance of Two Combination Pitot Pressure Probes

    NASA Technical Reports Server (NTRS)

    Arend, David J.; Saunders, John D.

    2009-01-01

    Experimental tests have been completed which recorded the ability of two combination steady state and high response time varying Pitot probe designs to accurately measure steady stagnation pressure at a single location in a flow field. Tests were conducted of double-barreled and coannular Prati probes in a 3.5 in. diameter free jet probe calibration facility from Mach 0.1 to 0.9. Geometric symmetry and pitch (-40 deg to 40 deg) and yaw (0 deg to 40 deg) angle actuation were used to fully evaluate the probes. These tests revealed that the double-barreled configuration induced error in its steady state measurement at zero incidence that increased consistently with jet Mach number to 1.1 percent at Mach 0.9. For all Mach numbers, the double-barreled probe nulled at a pitch angle of approximately 7.0 deg and provided inconsistent measurements when yawed. The double-barreled probe provided adequate measurements via both its steady state and high response tubes (within +/- 0.15 percent accuracy) over unacceptable ranges of biased pitch and inconsistent yaw angles which varied with Mach number. By comparison, the coannular probe provided accurate measurements (at zero incidence) for all jet Mach numbers as well as over a flow angularity range which varied from +/- 26.0 deg at Mach 0.3 deg to +/- 14.0 deg at Mach 0.9. Based on these results, the Prati probe is established as the preferred design. Further experimental tests are recommended to document the frequency response characteristics of the Prati probe.

  7. Experimental Study on Permeability of Concrete

    NASA Astrophysics Data System (ADS)

    Yang, Honglu; Liu, Rentai; Zheng, Zhuo; Liu, Haojie; Gao, Yan; Liu, Yankai

    2018-01-01

    To study the influencing factors on permeability of pervious concrete, by adding inorganic organic composite materials obtained experimental results show that different aggregate size, aggregate cement ratio of different, different water cement ratio on the permeability performance. The permeability of the concrete was tested by using the self - made permeable device. The experimental results showed that the permeation coefficient of the experiment was obtained and the factors influencing the permeability of the concrete were compared and analyzed. At the same time, the porosity of pervious concrete was measured, the influence of various variables on porosity was studied, and the influence of various factors on the permeability of voids was found. Finally, through comprehensive analysis of a variety of factors, the optimal water cement ratio is 0.28. At this time, the pervious performance of concrete is optimal.

  8. Small field output factors evaluation with a microDiamond detector over 30 Italian centers.

    PubMed

    Russo, Serenella; Reggiori, Giacomo; Cagni, Elisabetta; Clemente, Stefania; Esposito, Marco; Falco, Maria Daniela; Fiandra, Christian; Giglioli, Francesca Romana; Marinelli, Marco; Marino, Carmelo; Masi, Laura; Pimpinella, Maria; Stasi, Michele; Strigari, Lidia; Talamonti, Cinzia; Villaggi, Elena; Mancosu, Pietro

    2016-12-01

    The aim of the study was a multicenter evaluation of MLC&jaws-defined small field output factors (OF) for different linear accelerator manufacturers and for different beam energies using the latest synthetic single crystal diamond detector commercially available. The feasibility of providing an experimental OF data set, useful for on-site measurements validation, was also evaluated. This work was performed in the framework of the Italian Association of Medical Physics (AIFM) SBRT working group. The project was subdivided in two phases: in the first phase each center measured OFs using their own routine detector for nominal field sizes ranging from 10×10cm 2 to 0.6×0.6cm 2 . In the second phase, the measurements were repeated in all centers using the PTW 60019 microDiamond detector. The project enrolled 30 Italian centers. Micro-ion chambers and silicon diodes were used for OF measurements in 24 and 6 centers respectively. Gafchromic films and TLDs were used for very small field OFs in 3 and 1 centers. Regarding the measurements performed with the user's detectors, OF standard deviations (SD) for field sizes down to 2×2cm 2 were in all cases <2.7%. In the second phase, a reduction of around 50% of the SD was obtained using the microDiamond detector. The measured values presented in this multicenter study provide a consistent dataset for OFs that could be a useful tool for improving dosimetric procedures in centers. The microDiamond data present a small variation among the centers confirming that this detector can contribute to improve overall accuracy in radiotherapy. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  9. Evaluation of stratification factors and score-scales in clinical trials of treatment of clinical mastitis in dairy cows.

    PubMed

    Hektoen, L; Ødegaard, S A; Løken, T; Larsen, S

    2004-05-01

    There is often a need to reduce sample size in clinical trials due to practical limitations and ethical considerations. Better comparability between treatment groups by use of stratification in the design, and use of continuous outcome variables in the evaluation of treatment results, are two methods that can be used in order to achieve this. In this paper the choice of stratification factors in trials of clinical mastitis in dairy cows is investigated, and two score-scales for evaluation of clinical mastitis are introduced. The outcome in 57 dairy cows suffering from clinical mastitis and included in a clinical trial comparing homeopathic treatment, placebo and a standard antibiotic treatment is investigated. The strata of various stratification factors are compared across treatments to determine which other factors influence outcome. The two score scales, measuring acute and chronic mastitis symptoms, respectively, are evaluated on their ability to differentiate between patients classified from clinical criteria as responders or non-responders to treatment. Differences were found between the strata of the factors severity of mastitis, lactation number, previous mastitis this lactation and bacteriological findings. These factors influence outcome of treatment and appear relevant as stratification factors in mastitis trials. Both score scales differentiated between responders and non-responders to treatment and were found useful for evaluation of mastitis and mastitis treatment.

  10. Analytical and Experimental Evaluation of Digital Control Systems for the Semi-Span Super-Sonic Transport (S4T) Wind Tunnel Model

    NASA Technical Reports Server (NTRS)

    Wieseman, Carol D.; Christhilf, David; Perry, Boyd, III

    2012-01-01

    An important objective of the Semi-Span Super-Sonic Transport (S4T) wind tunnel model program was the demonstration of Flutter Suppression (FS), Gust Load Alleviation (GLA), and Ride Quality Enhancement (RQE). It was critical to evaluate the stability and robustness of these control laws analytically before testing them and experimentally while testing them to ensure safety of the model and the wind tunnel. MATLAB based software was applied to evaluate the performance of closed-loop systems in terms of stability and robustness. Existing software tools were extended to use analytical representations of the S4T and the control laws to analyze and evaluate the control laws prior to testing. Lessons were learned about the complex windtunnel model and experimental testing. The open-loop flutter boundary was determined from the closed-loop systems. A MATLAB/Simulink Simulation developed under the program is available for future work to improve the CPE process. This paper is one of a series of that comprise a special session, which summarizes the S4T wind-tunnel program.

  11. Factors affecting members' evaluation of agri-business ventures' effectiveness.

    PubMed

    Hashemi, Seyyed Mahmoud; Hedjazi, Yousef

    2011-02-01

    This paper presents work to identify factors affecting effectiveness of agri-business ventures (A-BVs) on the side of providers as perceived by their members. A survey was conducted among 95 members of A-BVs in Zanjan province, Iran. To collect data, a questionnaire was designed. Two distinct groups of A-BVs with low (group 1) and high (group 2) perceived (evaluated) levels of effectiveness were revealed. The study showed that there were significant differences between the two groups on important characteristics of A-BVs and their members. The study also found that there were statistically significant relationships between A-BVs' governance structure and capacity, management and organization characteristics and the perceived effectiveness, whereas there were no statistically significant relationships between A-BVs' advisory methods characteristic applied by members and the perceived effectiveness. Logistic regression results also showed that level of application of rules encouraging members' active participation in important decision makings, clear terms of reference to guide contracting procedures, roles, and responsibilities of parties involved, type of people served and geographical area of program coverage, and members' ability to use Information and Communication Technologies (ICTs) were predictors of the perceived (evaluated) effectiveness of A-BVs. The study showed that evaluation of members of effectiveness of A-BVs would not be the same. It is suggested that Iranian public agricultural extension organization, as responsible organization for monitoring and evaluating services conducted by A-BVs, considered these differences between members with different levels of some important variables. 2010 Elsevier Ltd. All rights reserved.

  12. Evaluation of medication alerts in electronic health records for compliance with human factors principles

    PubMed Central

    Phansalkar, Shobha; Zachariah, Marianne; Seidling, Hanna M; Mendes, Chantal; Volk, Lynn; Bates, David W

    2014-01-01

    Introduction Increasing the adoption of electronic health records (EHRs) with integrated clinical decision support (CDS) is a key initiative of the current US healthcare administration. High over-ride rates of CDS alerts strongly limit these potential benefits. As a result, EHR designers aspire to improve alert design to achieve better acceptance rates. In this study, we evaluated drug–drug interaction (DDI) alerts generated in EHRs and compared them for compliance with human factors principles. Methods We utilized a previously validated questionnaire, the I-MeDeSA, to assess compliance with nine human factors principles of DDI alerts generated in 14 EHRs. Two reviewers independently assigned scores evaluating the human factors characteristics of each EHR. Rankings were assigned based on these scores and recommendations for appropriate alert design were derived. Results The 14 EHRs evaluated in this study received scores ranging from 8 to 18.33, with a maximum possible score of 26. Cohen's κ (κ=0.86) reflected excellent agreement among reviewers. The six vendor products tied for second and third place rankings, while the top system and bottom five systems were home-grown products. The most common weaknesses included the absence of characteristics such as alert prioritization, clear and concise alert messages indicating interacting drugs, actions for clinical management, and a statement indicating the consequences of over-riding the alert. Conclusions We provided detailed analyses of the human factors principles which were assessed and described our recommendations for effective alert design. Future studies should assess whether adherence to these recommendations can improve alert acceptance. PMID:24780721

  13. Optimizing experimental procedures for quantitative evaluation of crop plant performance in high throughput phenotyping systems

    PubMed Central

    Junker, Astrid; Muraya, Moses M.; Weigelt-Fischer, Kathleen; Arana-Ceballos, Fernando; Klukas, Christian; Melchinger, Albrecht E.; Meyer, Rhonda C.; Riewe, David; Altmann, Thomas

    2015-01-01

    Detailed and standardized protocols for plant cultivation in environmentally controlled conditions are an essential prerequisite to conduct reproducible experiments with precisely defined treatments. Setting up appropriate and well defined experimental procedures is thus crucial for the generation of solid evidence and indispensable for successful plant research. Non-invasive and high throughput (HT) phenotyping technologies offer the opportunity to monitor and quantify performance dynamics of several hundreds of plants at a time. Compared to small scale plant cultivations, HT systems have much higher demands, from a conceptual and a logistic point of view, on experimental design, as well as the actual plant cultivation conditions, and the image analysis and statistical methods for data evaluation. Furthermore, cultivation conditions need to be designed that elicit plant performance characteristics corresponding to those under natural conditions. This manuscript describes critical steps in the optimization of procedures for HT plant phenotyping systems. Starting with the model plant Arabidopsis, HT-compatible methods were tested, and optimized with regard to growth substrate, soil coverage, watering regime, experimental design (considering environmental inhomogeneities) in automated plant cultivation and imaging systems. As revealed by metabolite profiling, plant movement did not affect the plants' physiological status. Based on these results, procedures for maize HT cultivation and monitoring were established. Variation of maize vegetative growth in the HT phenotyping system did match well with that observed in the field. The presented results outline important issues to be considered in the design of HT phenotyping experiments for model and crop plants. It thereby provides guidelines for the setup of HT experimental procedures, which are required for the generation of reliable and reproducible data of phenotypic variation for a broad range of applications. PMID

  14. Near-optimal experimental design for model selection in systems biology.

    PubMed

    Busetto, Alberto Giovanni; Hauser, Alain; Krummenacher, Gabriel; Sunnåker, Mikael; Dimopoulos, Sotiris; Ong, Cheng Soon; Stelling, Jörg; Buhmann, Joachim M

    2013-10-15

    Biological systems are understood through iterations of modeling and experimentation. Not all experiments, however, are equally valuable for predictive modeling. This study introduces an efficient method for experimental design aimed at selecting dynamical models from data. Motivated by biological applications, the method enables the design of crucial experiments: it determines a highly informative selection of measurement readouts and time points. We demonstrate formal guarantees of design efficiency on the basis of previous results. By reducing our task to the setting of graphical models, we prove that the method finds a near-optimal design selection with a polynomial number of evaluations. Moreover, the method exhibits the best polynomial-complexity constant approximation factor, unless P = NP. We measure the performance of the method in comparison with established alternatives, such as ensemble non-centrality, on example models of different complexity. Efficient design accelerates the loop between modeling and experimentation: it enables the inference of complex mechanisms, such as those controlling central metabolic operation. Toolbox 'NearOED' available with source code under GPL on the Machine Learning Open Source Software Web site (mloss.org).

  15. Review of existing experimental approaches for the clinical evaluation of the benefits of plant food supplements on cardiovascular function.

    PubMed

    Meoni, Paolo; Restani, Patrizia; Mancama, Dalu T

    2013-06-01

    We conducted a survey of the National Centre for Biotechnology Information (NCBI) PubMed database to identify methods most commonly used for the evaluation of the effect of plant food supplements on the cardiovascular system and their relevance to the regulatory status of these products. Particularly, our search strategy was aimed at the selection of studies concerning the clinical evaluation of the beneficial effects of the most commonly studied plant food supplements acting on the cardiovascular system. Following the screening of 3839 papers for inclusion criteria, 48 published reports were retained for this review. Most studies included in this review used a double blind controlled design, and evaluated the effect of plant food supplements on individuals affected by a disease of the cardiovascular system. The majority of the studies were found to be of low methodological quality on the Jadad scale, mainly because of inadequate reporting of adverse events and of patient withdrawals. In comparison, measures used for the evaluation of benefits included mostly cardiovascular risk factors as recommended in international guidelines and in accordance with principles laid down for the evaluation of health claims in food. The risk factors most frequently evaluated belonged to the category of "lipid function and levels", "heart function" and "blood pressure". For the absolute majority of the studies, the study period did not exceed one month. This review highlights critical factors to be considered in the design of studies evaluating the health effects of plant food supplements on the cardiovascular system. Between others, the inclusion of healthy individuals, better reporting and description of the characteristics of the product used could improve the quality and relevance of these studies.

  16. Evaluation of B2C website based on the usability factors by using fuzzy AHP & hierarchical fuzzy TOPSIS

    NASA Astrophysics Data System (ADS)

    Masudin, I.; Saputro, T. E.

    2016-02-01

    In today's technology, electronic trading transaction via internet has been utilized properly with rapid growth. This paper intends to evaluate related to B2C e-commerce website in order to find out the one which meets the usability factors better than another. The influential factors to B2C e-commerce website are determined for two big retailer websites. The factors are investigated based on the consideration of several studies and conformed to the website characteristics. The evaluation is conducted by using different methods namely fuzzy AHP and hierarchical fuzzy TOPSIS so that the final evaluation can be compared. Fuzzy triangular number is adopted to deal with imprecise judgment under fuzzy environment.

  17. Evaluation of experimental flexible pavements : interim report no. 1, construction of Altavista Bypass experimental pavement.

    DOT National Transportation Integrated Search

    1974-01-01

    Deflection tests conducted during the construction and shortly after the completion of a large experimental pavement project are reported. Four different pavement designs, as follows, are compared: 1. 6-inch cement stabilized subgrade, 6-inch crushed...

  18. The evaluation of the individual impact factor of researchers and research centers using the RC algorithm.

    PubMed

    Cordero-Villafáfila, Amelia; Ramos-Brieva, Jesus A

    2015-01-01

    The RC algorithm quantitatively evaluates the personal impact factor of the scientific production of isolated researchers. The authors propose an adaptation of RC to evaluate the personal impact factor of research centers, hospitals and other research groups. Thus, these could be classified according to the accredited impact of the results of their scientific work between researchers of the same scientific area. This could be useful for channelling budgets and grants for research. Copyright © 2013 SEP y SEPB. Published by Elsevier España. All rights reserved.

  19. Biomedical and Human Factors Requirements for a Manned Earth Orbiting Station

    NASA Technical Reports Server (NTRS)

    Helvey, W.; Martell, C.; Peters, J.; Rosenthal, G.; Benjamin, F.; Albright, G.

    1964-01-01

    The primary objective of this study is to determine which biomedical and human factors measurements must be made aboard a space station to assure adequate evaluation of the astronaut's health and performance during prolonged space flights. The study has employed, where possible, a medical and engineering systems analysis to define the pertinent life sciences and space station design parameters and their influence on a measurement program. The major areas requiring evaluation in meeting the study objectives include a definition of the space environment, man's response to the environment, selection of measurement and data management techniques, experimental program, space station design requirements, and a trade-off analysis with final recommendations. The space environment factors that are believed to have a significant effect on man were evaluated. This includes those factors characteristic of the space environment (e. g. weightlessness, radiation) as well as those created within the space station (e. g. toxic contaminants, capsule atmosphere). After establishing the general features of the environment, an appraisal was made of the anticipated response of the astronaut to each of these factors. For thoroughness, the major organ systems and functions of the body were delineated, and a determination was made of their anticipated response to each of the environmental categories. A judgment was then made on the medical significance or importance of each response, which enabled a determination of which physiological and psychological effects should be monitored. Concurrently, an extensive list of measurement techniques and methods of data management was evaluated for applicability to the space station program. The various space station configurations and design parameters were defined in terms of the biomedical and human factors requirements to provide the measurements program. Research design of experimental programs for various station configurations, mission

  20. Fundamental period of Italian reinforced concrete buildings: comparison between numerical, experimental and Italian code simplified values

    NASA Astrophysics Data System (ADS)

    Ditommaso, Rocco; Carlo Ponzo, Felice; Auletta, Gianluca; Iacovino, Chiara; Nigro, Antonella

    2015-04-01

    Aim of this study is a comparison among the fundamental period of reinforced concrete buildings evaluated using the simplified approach proposed by the Italian Seismic code (NTC 2008), numerical models and real values retrieved from an experimental campaign performed on several buildings located in Basilicata region (Italy). With the intention of proposing simplified relationships to evaluate the fundamental period of reinforced concrete buildings, scientists and engineers performed several numerical and experimental campaigns, on different structures all around the world, to calibrate different kind of formulas. Most of formulas retrieved from both numerical and experimental analyses provides vibration periods smaller than those suggested by the Italian seismic code. However, it is well known that the fundamental period of a structure play a key role in the correct evaluation of the spectral acceleration for seismic static analyses. Generally, simplified approaches impose the use of safety factors greater than those related to in depth nonlinear analyses with the aim to cover possible unexpected uncertainties. Using the simplified formula proposed by the Italian seismic code the fundamental period is quite higher than fundamental periods experimentally evaluated on real structures, with the consequence that the spectral acceleration adopted in the seismic static analysis may be significantly different than real spectral acceleration. This approach could produces a decreasing in safety factors obtained using linear and nonlinear seismic static analyses. Finally, the authors suggest a possible update of the Italian seismic code formula for the simplified estimation of the fundamental period of vibration of existing RC buildings, taking into account both elastic and inelastic structural behaviour and the interaction between structural and non-structural elements. Acknowledgements This study was partially funded by the Italian Civil Protection Department within the